* [PATCH v3 00/38] idmapped mounts
@ 2020-11-28 21:34 Christian Brauner
2020-11-28 21:34 ` [PATCH v3 01/38] namespace: take lock_mount_hash() directly when changing flags Christian Brauner
` (36 more replies)
0 siblings, 37 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:34 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner
Hey everyone,
/* v3 */
- The major change is the port of the test-suite from the
kernel-internal selftests framework to xfstests as requested by
Darrick and Christoph. The test-suite for xfstests is patch 38 in this
series. It has been kept as part of this series even though it belongs
to xfstests so it's easier to see what is tested and to keep it
in-sync.
- Note, the test-suite now has been extended to cover io_uring and
idmapped mounts. The IORING_REGISTER_PERSONALITY feature allows to
register the caller's credentials with io_uring and returns an id
associated with these credentials. This is useful for applications
that wish to share a ring between separate users/processes. Callers
can pass in the credential id in the sqe personality field. If set,
that particular sqe will be issued with these credentials.
The test-suite now tests that the openat* operations with different
registered credentials work correctly and safely on regular mounts, on
regular mounts inside user namespaces, on idmapped mounts, and on
idmapped mounts inside user namespaces.
/* v2 */
- The major change is the rework requested by Christoph and others to
adapt all relevant helpers and inode_operations methods to account for
idmapped mounts instead of introducing new helpers and methods
specific to idmapped mounts like we did before. We've also moved the
overlayfs conversion to handle idmapped mounts into a separate
patchset that will be sent out separately after the core changes
landed. The converted filesytems in this series include fat and ext4.
As per Christoph's request the vfs-wide config option to disable
idmapped mounts has been removed. Instead the filesystems can decide
whether or not they want to allow idmap mounts through a config
option. These config options default to off. Having a config option
allows us to gain some confidence in the patchset over multiple kernel
releases.
- This version introduces a large test-suite to test current vfs
behavior and idmapped mounts behavior. This test-suite is intended to
grow over time.
- While while working on adapting this patchset to the requested
changes, the runC and containerd crowd was nice enough to adapt
containerd to this patchset to make use of idmapped mounts in one of
the most widely used container runtimes:
https://github.com/containerd/containerd/pull/4734
With this patchset we make it possible to attach idmappings to mounts.
This handles several common use-cases. Here are just a few:
- Shifting of a container rootfs or base image without having to mangle
every file (runc, Docker, containerd, k8s, LXD, systemd ...)
- Sharing of data between host or privileged containers with
underprivileged containers (runc, Docker, containerd, k8s, LXD, ...)
- Shifting of subset of ownership-less filesystems (vfat) for use by
multiple users, effectively allowing for DAC on such devices (systemd,
Android, ...)
- Data sharing between multiple user namespaces with incompatible maps
(LXD, k8s, ...)
Making it possible to share directories and mounts between users with
different uids and gids is itself quite an important use-case in
distributed systems environments. It's of course especially useful in
general for portable usb sticks, sharing data between multiple users in
general, and sharing home directories between multiple users. The last
example is now elegantly expressed in systemd's homed concept for
portable home directories. As mentioned above, idmapped mounts also
allow data from the host to be shared with unprivileged containers,
between privileged and unprivileged containers simultaneously and in
addition also between unprivileged containers with different idmappings
whenever they are used to isolate one container completely from another
container.
As can be seen from answers to earlier threads of this patchset and from
the list of potential users interest in this patchset is widespread.
We have implemented and proposed multiple solutions to this before. This
included the introduction of fsid mappings, a tiny filesystem that is
currently carried in Ubuntu that has shown it's limitations, and an
approach to call override creds in the vfs. None of these solutions have
covered all of the above use-cases. Some of them have been fairly hacky
too by e.g. violating how things should be passed down to the individual
filesystems.
The solution proposed here has it's origins in multiple discussions
during Linux Plumbers 2017 during and after the end of the containers
microconference.
To the best of my knowledge this involved Aleksa, Stéphane, Eric, David,
James, and myself. The original idea or a variant thereof has been
discussed, again to the best of my knowledge, after a Linux conference
in St. Petersburg in Russia in 2017 between Christoph, Tycho, and
myself.
We've taken the time to implement a working version of this solution
over the last weeks to the best of my abilities. Tycho has signed up
for this sligthly crazy endeavour as well and he has helped with the
conversion of the xattr codepaths and will be involved with others in
converting additional filesystems.
Idmappings become a property of struct vfsmount instead of tying it to a
process being inside of a user namespace which has been the case for all
other proposed approaches. It also allows to pass down the user
namespace into the filesystems which is a clean way instead of violating
calling conventions by strapping the user namespace information that is
a property of the mount to the caller's credentials or similar hacks.
Each mount can have a separate idmapping and idmapped mounts can even be
created in the initial user namespace unblocking a range of use-cases.
To this end the vfsmount struct gains a new struct user_namespace
member. The idmapping of the user namespace becomes the idmapping of the
mount. A caller that is privileged with respect to the user namespace of
the superblock of the underlying filesystem can create an idmapped
mount. In the future, we can enable unprivileged use-cases by checking
whether the caller is privileged wrt to the user namespace than an
already idmapped mount has been marked with, allowing them to change the
idmapping. For now, keep things simple until we feel sure enough.
Note, that with syscall interception it is already possible to intercept
idmapped mount requests from unprivileged containers and handle them in
a sufficiently privileged container manager. Support for this is already
available in LXD and will be available in runC were syscall interception
is currently in the process of becoming part of the runtime spec:
https://github.com/opencontainers/runtime-spec/pull/1074.
The user namespace the mount will be marked with can be specified by
passing a file descriptor refering to the user namespace as an argument
to the new mount_setattr() syscall together with the new
MOUNT_ATTR_IDMAP flag. By default vfsmounts are marked with the initial
user namespace and no behavioral or performance changes should be
observed. All mapping operations are nops for the initial user
namespace. When a file/inode is accessed through an idmapped mount the
i_uid and i_gid of the inode will be remapped according to the user
namespace the mount has been marked with.
In order to support idmapped mounts, filesystems need to be changed and
mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The initial
version contains fat and ext4 including a list of examples. But patches
for other filesystems are actively worked on but will be sent out
separately. We are here to see this through and there are multiple
people involved in converting filesystems. So filesystem developers are
not left alone with this.
There is a simple tool available at
https://github.com/brauner/mount-idmapped that allows to create idmapped
mounts so people can play with this patch series. Here are a few
illustrations:
1. Create a simple idmapped mount of another user's home directory
u1001@f2-vm:/$ sudo ./mount-idmapped --map-mount b:1000:1001:1 /home/ubuntu/ /mnt
u1001@f2-vm:/$ ls -al /home/ubuntu/
total 28
drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
drwxr-xr-x 4 root root 4096 Oct 28 04:00 ..
-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile
-rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ ls -al /mnt/
total 28
drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 .
drwxr-xr-x 29 root root 4096 Oct 28 22:01 ..
-rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile
-rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ touch /mnt/my-file
u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file
u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file
u1001@f2-vm:/$ ls -al /mnt/my-file
-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file
u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file
u1001@f2-vm:/$ getfacl /mnt/my-file
getfacl: Removing leading '/' from absolute path names
# file: mnt/my-file
# owner: u1001
# group: u1001
user::rw-
user:u1001:rwx
group::rw-
mask::rwx
other::r--
u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
getfacl: Removing leading '/' from absolute path names
# file: home/ubuntu/my-file
# owner: ubuntu
# group: ubuntu
user::rw-
user:ubuntu:rwx
group::rw-
mask::rwx
other::r--
2. Create mapping of the whole ext4 rootfs without a mapping for uid and gid 0
ubuntu@f2-vm:~$ sudo /mount-idmapped --map-mount b:1:1:65536 / /mnt/
ubuntu@f2-vm:~$ findmnt | grep mnt
└─/mnt /dev/sda2 ext4 rw,relatime
└─/mnt/mnt /dev/sda2 ext4 rw,relatime
ubuntu@f2-vm:~$ sudo mkdir /AS-ROOT-CAN-CREATE
ubuntu@f2-vm:~$ sudo mkdir /mnt/AS-ROOT-CANT-CREATE
mkdir: cannot create directory ‘/mnt/AS-ROOT-CANT-CREATE’: Value too large for defined data type
ubuntu@f2-vm:~$ mkdir /mnt/home/ubuntu/AS-USER-1000-CAN-CREATE
3. Create a vfat usb mount and expose to user 1001 and 5000
ubuntu@f2-vm:/$ sudo mount /dev/sdb /mnt
ubuntu@f2-vm:/$ findmnt | grep mnt
└─/mnt /dev/sdb vfat rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro
ubuntu@f2-vm:/$ ls -al /mnt
total 12
drwxr-xr-x 2 root root 4096 Jan 1 1970 .
drwxr-xr-x 34 root root 4096 Oct 28 22:24 ..
-rwxr-xr-x 1 root root 4 Oct 28 03:44 aaa
-rwxr-xr-x 1 root root 0 Oct 28 01:09 bbb
ubuntu@f2-vm:/$ sudo /mount-idmapped --map-mount b:0:1001:1 /mnt /mnt-1001/
ubuntu@f2-vm:/$ ls -al /mnt-1001/
total 12
drwxr-xr-x 2 u1001 u1001 4096 Jan 1 1970 .
drwxr-xr-x 34 root root 4096 Oct 28 22:24 ..
-rwxr-xr-x 1 u1001 u1001 4 Oct 28 03:44 aaa
-rwxr-xr-x 1 u1001 u1001 0 Oct 28 01:09 bbb
ubuntu@f2-vm:/$ sudo /mount-idmapped --map-mount b:0:5000:1 /mnt /mnt-5000/
ubuntu@f2-vm:/$ ls -al /mnt-5000/
total 12
drwxr-xr-x 2 5000 5000 4096 Jan 1 1970 .
drwxr-xr-x 34 root root 4096 Oct 28 22:24 ..
-rwxr-xr-x 1 5000 5000 4 Oct 28 03:44 aaa
-rwxr-xr-x 1 5000 5000 0 Oct 28 01:09 bbb
4. Create an idmapped rootfs mount for a container
root@f2-vm:~# ls -al /var/lib/lxc/f2/rootfs/
total 68
drwxr-xr-x 17 20000 20000 4096 Sep 24 07:48 .
drwxrwx--- 3 20000 20000 4096 Oct 16 19:26 ..
lrwxrwxrwx 1 20000 20000 7 Sep 24 07:43 bin -> usr/bin
drwxr-xr-x 2 20000 20000 4096 Apr 15 2020 boot
drwxr-xr-x 3 20000 20000 4096 Oct 16 19:26 dev
drwxr-xr-x 61 20000 20000 4096 Oct 16 19:26 etc
drwxr-xr-x 3 20000 20000 4096 Sep 24 07:45 home
lrwxrwxrwx 1 20000 20000 7 Sep 24 07:43 lib -> usr/lib
lrwxrwxrwx 1 20000 20000 9 Sep 24 07:43 lib32 -> usr/lib32
lrwxrwxrwx 1 20000 20000 9 Sep 24 07:43 lib64 -> usr/lib64
lrwxrwxrwx 1 20000 20000 10 Sep 24 07:43 libx32 -> usr/libx32
drwxr-xr-x 2 20000 20000 4096 Sep 24 07:43 media
drwxr-xr-x 2 20000 20000 4096 Sep 24 07:43 mnt
drwxr-xr-x 2 20000 20000 4096 Sep 24 07:43 opt
drwxr-xr-x 2 20000 20000 4096 Apr 15 2020 proc
drwx------ 2 20000 20000 4096 Sep 24 07:43 root
drwxr-xr-x 2 20000 20000 4096 Sep 24 07:45 run
lrwxrwxrwx 1 20000 20000 8 Sep 24 07:43 sbin -> usr/sbin
drwxr-xr-x 2 20000 20000 4096 Sep 24 07:43 srv
drwxr-xr-x 2 20000 20000 4096 Apr 15 2020 sys
drwxrwxrwt 2 20000 20000 4096 Sep 24 07:44 tmp
drwxr-xr-x 13 20000 20000 4096 Sep 24 07:43 usr
drwxr-xr-x 12 20000 20000 4096 Sep 24 07:44 var
root@f2-vm:~# /mount-idmapped --map-mount b:20000:10000:100000 /var/lib/lxc/f2/rootfs/ /mnt
root@f2-vm:~# ls -al /mnt
total 68
drwxr-xr-x 17 10000 10000 4096 Sep 24 07:48 .
drwxr-xr-x 34 root root 4096 Oct 28 22:24 ..
lrwxrwxrwx 1 10000 10000 7 Sep 24 07:43 bin -> usr/bin
drwxr-xr-x 2 10000 10000 4096 Apr 15 2020 boot
drwxr-xr-x 3 10000 10000 4096 Oct 16 19:26 dev
drwxr-xr-x 61 10000 10000 4096 Oct 16 19:26 etc
drwxr-xr-x 3 10000 10000 4096 Sep 24 07:45 home
lrwxrwxrwx 1 10000 10000 7 Sep 24 07:43 lib -> usr/lib
lrwxrwxrwx 1 10000 10000 9 Sep 24 07:43 lib32 -> usr/lib32
lrwxrwxrwx 1 10000 10000 9 Sep 24 07:43 lib64 -> usr/lib64
lrwxrwxrwx 1 10000 10000 10 Sep 24 07:43 libx32 -> usr/libx32
drwxr-xr-x 2 10000 10000 4096 Sep 24 07:43 media
drwxr-xr-x 2 10000 10000 4096 Sep 24 07:43 mnt
drwxr-xr-x 2 10000 10000 4096 Sep 24 07:43 opt
drwxr-xr-x 2 10000 10000 4096 Apr 15 2020 proc
drwx------ 2 10000 10000 4096 Sep 24 07:43 root
drwxr-xr-x 2 10000 10000 4096 Sep 24 07:45 run
lrwxrwxrwx 1 10000 10000 8 Sep 24 07:43 sbin -> usr/sbin
drwxr-xr-x 2 10000 10000 4096 Sep 24 07:43 srv
drwxr-xr-x 2 10000 10000 4096 Apr 15 2020 sys
drwxrwxrwt 2 10000 10000 4096 Sep 24 07:44 tmp
drwxr-xr-x 13 10000 10000 4096 Sep 24 07:43 usr
drwxr-xr-x 12 10000 10000 4096 Sep 24 07:44 var
root@f2-vm:~# lxc-start f2 # uses /mnt as rootfs
root@f2-vm:~# lxc-attach f2 -- cat /proc/1/uid_map
0 10000 10000
root@f2-vm:~# lxc-attach f2 -- cat /proc/1/gid_map
0 10000 10000
root@f2-vm:~# lxc-attach f2 -- ls -al /
total 52
drwxr-xr-x 17 root root 4096 Sep 24 07:48 .
drwxr-xr-x 17 root root 4096 Sep 24 07:48 ..
lrwxrwxrwx 1 root root 7 Sep 24 07:43 bin -> usr/bin
drwxr-xr-x 2 root root 4096 Apr 15 2020 boot
drwxr-xr-x 5 root root 500 Oct 28 23:39 dev
drwxr-xr-x 61 root root 4096 Oct 28 23:39 etc
drwxr-xr-x 3 root root 4096 Sep 24 07:45 home
lrwxrwxrwx 1 root root 7 Sep 24 07:43 lib -> usr/lib
lrwxrwxrwx 1 root root 9 Sep 24 07:43 lib32 -> usr/lib32
lrwxrwxrwx 1 root root 9 Sep 24 07:43 lib64 -> usr/lib64
lrwxrwxrwx 1 root root 10 Sep 24 07:43 libx32 -> usr/libx32
drwxr-xr-x 2 root root 4096 Sep 24 07:43 media
drwxr-xr-x 2 root root 4096 Sep 24 07:43 mnt
drwxr-xr-x 2 root root 4096 Sep 24 07:43 opt
dr-xr-xr-x 232 nobody nogroup 0 Oct 28 23:39 proc
drwx------ 2 root root 4096 Oct 28 23:41 root
drwxr-xr-x 12 root root 360 Oct 28 23:39 run
lrwxrwxrwx 1 root root 8 Sep 24 07:43 sbin -> usr/sbin
drwxr-xr-x 2 root root 4096 Sep 24 07:43 srv
dr-xr-xr-x 13 nobody nogroup 0 Oct 28 23:39 sys
drwxrwxrwt 11 root root 4096 Oct 28 23:40 tmp
drwxr-xr-x 13 root root 4096 Sep 24 07:43 usr
drwxr-xr-x 12 root root 4096 Sep 24 07:44 var
root@f2-vm:~# lxc-attach f2 -- ls -al /my-file
-rw-r--r-- 1 root root 0 Oct 28 23:43 /my-file
root@f2-vm:~# ls -al /var/lib/lxc/f2/rootfs/my-file
-rw-r--r-- 1 20000 20000 0 Oct 28 23:43 /var/lib/lxc/f2/rootfs/my-file
I'd like to say thanks to:
Al for pointing me into the direction to avoid inode alias issues during
lookup. David for various discussions around this. Christoph for proving
a first proper review and for being involved in the original idea. Tycho
for helping with this series and on future patches to convert
filesystems. Alban Crequy and the Kinvolk located just a few streets
away from me in Berlin for providing use-case discussions and writing
patches for containerd! Stéphane for his invaluable input on many things
and level head and enabling me to work on this. Amir for explaining and
discussing aspects of overlayfs with me. I'd like to especially thank
Seth Forshee because he provided a lot of good analysis, suggestions,
and participated in short-notice discussions in both chat and video for
some nitty-gritty technical details.
This series can be found and pulled from the three usual locations:
https://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux.git/log/?h=idmapped_mounts
https://github.com/brauner/linux/tree/idmapped_mounts
https://gitlab.com/brauner/linux/-/commits/idmapped_mounts
Thanks!
Christian
Christian Brauner (36):
namespace: take lock_mount_hash() directly when changing flags
mount: make {lock,unlock}_mount_hash() static
namespace: only take read lock in do_reconfigure_mnt()
fs: add mount_setattr()
tests: add mount_setattr() selftests
fs: add id translation helpers
mount: attach mappings to mounts
capability: handle idmapped mounts
namei: add idmapped mount aware permission helpers
inode: add idmapped mount aware init and permission helpers
attr: handle idmapped mounts
acl: handle idmapped mounts
commoncap: handle idmapped mounts
stat: handle idmapped mounts
namei: handle idmapped mounts in may_*() helpers
namei: introduce struct renamedata
namei: prepare for idmapped mounts
open: handle idmapped mounts in do_truncate()
open: handle idmapped mounts
af_unix: handle idmapped mounts
utimes: handle idmapped mounts
fcntl: handle idmapped mounts
notify: handle idmapped mounts
init: handle idmapped mounts
ioctl: handle idmapped mounts
would_dump: handle idmapped mounts
exec: handle idmapped mounts
fs: add helpers for idmap mounts
apparmor: handle idmapped mounts
ima: handle idmapped mounts
fat: handle idmapped mounts
ext4: support idmapped mounts
ecryptfs: do not mount on top of idmapped mounts
overlayfs: do not mount on top of idmapped mounts
fs: introduce MOUNT_ATTR_IDMAP
tests: extend mount_setattr tests
Tycho Andersen (1):
xattr: handle idmapped mounts
Documentation/filesystems/locking.rst | 6 +-
Documentation/filesystems/porting.rst | 2 +
Documentation/filesystems/vfs.rst | 17 +-
arch/alpha/kernel/syscalls/syscall.tbl | 1 +
arch/arm/tools/syscall.tbl | 1 +
arch/arm64/include/asm/unistd32.h | 2 +
arch/ia64/kernel/syscalls/syscall.tbl | 1 +
arch/m68k/kernel/syscalls/syscall.tbl | 1 +
arch/microblaze/kernel/syscalls/syscall.tbl | 1 +
arch/mips/kernel/syscalls/syscall_n32.tbl | 1 +
arch/mips/kernel/syscalls/syscall_n64.tbl | 1 +
arch/mips/kernel/syscalls/syscall_o32.tbl | 1 +
arch/parisc/kernel/syscalls/syscall.tbl | 1 +
arch/powerpc/kernel/syscalls/syscall.tbl | 1 +
arch/powerpc/platforms/cell/spufs/inode.c | 5 +-
arch/s390/kernel/syscalls/syscall.tbl | 1 +
arch/sh/kernel/syscalls/syscall.tbl | 1 +
arch/sparc/kernel/syscalls/syscall.tbl | 1 +
arch/x86/entry/syscalls/syscall_32.tbl | 1 +
arch/x86/entry/syscalls/syscall_64.tbl | 1 +
arch/xtensa/kernel/syscalls/syscall.tbl | 1 +
drivers/android/binderfs.c | 6 +-
drivers/base/devtmpfs.c | 12 +-
fs/9p/acl.c | 7 +-
fs/9p/v9fs.h | 3 +-
fs/9p/v9fs_vfs.h | 2 +-
fs/9p/vfs_inode.c | 32 +-
fs/9p/vfs_inode_dotl.c | 34 +-
fs/9p/xattr.c | 1 +
fs/adfs/adfs.h | 3 +-
fs/adfs/inode.c | 5 +-
fs/affs/affs.h | 10 +-
fs/affs/inode.c | 7 +-
fs/affs/namei.c | 15 +-
fs/afs/dir.c | 34 +-
fs/afs/inode.c | 5 +-
fs/afs/internal.h | 4 +-
fs/afs/security.c | 2 +-
fs/afs/xattr.c | 2 +
fs/attr.c | 82 +-
fs/autofs/root.c | 13 +-
fs/bad_inode.c | 31 +-
fs/bfs/dir.c | 12 +-
fs/btrfs/acl.c | 5 +-
fs/btrfs/ctree.h | 3 +-
fs/btrfs/inode.c | 41 +-
fs/btrfs/ioctl.c | 25 +-
fs/btrfs/tests/btrfs-tests.c | 2 +-
fs/btrfs/xattr.c | 2 +
fs/cachefiles/interface.c | 4 +-
fs/cachefiles/namei.c | 19 +-
fs/cachefiles/xattr.c | 16 +-
fs/ceph/acl.c | 5 +-
fs/ceph/dir.c | 23 +-
fs/ceph/inode.c | 13 +-
fs/ceph/super.h | 8 +-
fs/ceph/xattr.c | 1 +
fs/cifs/cifsfs.c | 4 +-
fs/cifs/cifsfs.h | 18 +-
fs/cifs/dir.c | 8 +-
fs/cifs/inode.c | 22 +-
fs/cifs/link.c | 3 +-
fs/cifs/xattr.c | 1 +
fs/coda/coda_linux.h | 4 +-
fs/coda/dir.c | 18 +-
fs/coda/inode.c | 5 +-
fs/coda/pioctl.c | 6 +-
fs/configfs/configfs_internal.h | 7 +-
fs/configfs/dir.c | 3 +-
fs/configfs/inode.c | 5 +-
fs/configfs/symlink.c | 5 +-
fs/coredump.c | 12 +-
fs/crypto/policy.c | 2 +-
fs/debugfs/inode.c | 9 +-
fs/ecryptfs/crypto.c | 4 +-
fs/ecryptfs/inode.c | 74 +-
fs/ecryptfs/main.c | 6 +
fs/ecryptfs/mmap.c | 4 +-
fs/efivarfs/file.c | 2 +-
fs/efivarfs/inode.c | 4 +-
fs/erofs/inode.c | 2 +-
fs/exec.c | 12 +-
fs/exfat/exfat_fs.h | 3 +-
fs/exfat/file.c | 9 +-
fs/exfat/namei.c | 13 +-
fs/ext2/acl.c | 5 +-
fs/ext2/acl.h | 3 +-
fs/ext2/ext2.h | 2 +-
fs/ext2/ialloc.c | 2 +-
fs/ext2/inode.c | 11 +-
fs/ext2/ioctl.c | 6 +-
fs/ext2/namei.c | 22 +-
fs/ext2/xattr_security.c | 1 +
fs/ext2/xattr_trusted.c | 1 +
fs/ext2/xattr_user.c | 1 +
fs/ext4/Kconfig | 9 +
fs/ext4/acl.c | 5 +-
fs/ext4/acl.h | 3 +-
fs/ext4/ext4.h | 15 +-
fs/ext4/ialloc.c | 7 +-
fs/ext4/inode.c | 14 +-
fs/ext4/ioctl.c | 18 +-
fs/ext4/namei.c | 52 +-
fs/ext4/super.c | 6 +-
fs/ext4/xattr_hurd.c | 1 +
fs/ext4/xattr_security.c | 1 +
fs/ext4/xattr_trusted.c | 1 +
fs/ext4/xattr_user.c | 1 +
fs/f2fs/acl.c | 5 +-
fs/f2fs/acl.h | 3 +-
fs/f2fs/f2fs.h | 3 +-
fs/f2fs/file.c | 31 +-
fs/f2fs/namei.c | 26 +-
fs/f2fs/xattr.c | 4 +-
fs/fat/fat.h | 3 +-
fs/fat/file.c | 20 +-
fs/fat/namei_msdos.c | 15 +-
fs/fat/namei_vfat.c | 15 +-
fs/fcntl.c | 3 +-
fs/fuse/acl.c | 3 +-
fs/fuse/dir.c | 41 +-
fs/fuse/fuse_i.h | 4 +-
fs/fuse/xattr.c | 2 +
fs/gfs2/acl.c | 5 +-
fs/gfs2/acl.h | 3 +-
fs/gfs2/file.c | 4 +-
fs/gfs2/inode.c | 54 +-
fs/gfs2/inode.h | 2 +-
fs/gfs2/xattr.c | 1 +
fs/hfs/attr.c | 1 +
fs/hfs/dir.c | 13 +-
fs/hfs/hfs_fs.h | 2 +-
fs/hfs/inode.c | 7 +-
fs/hfsplus/dir.c | 25 +-
fs/hfsplus/inode.c | 11 +-
fs/hfsplus/ioctl.c | 2 +-
fs/hfsplus/xattr.c | 1 +
fs/hfsplus/xattr_security.c | 1 +
fs/hfsplus/xattr_trusted.c | 1 +
fs/hfsplus/xattr_user.c | 1 +
fs/hostfs/hostfs_kern.c | 31 +-
fs/hpfs/hpfs_fn.h | 2 +-
fs/hpfs/inode.c | 7 +-
fs/hpfs/namei.c | 20 +-
fs/hugetlbfs/inode.c | 31 +-
fs/init.c | 23 +-
fs/inode.c | 38 +-
fs/internal.h | 9 +
fs/jffs2/acl.c | 5 +-
fs/jffs2/acl.h | 3 +-
fs/jffs2/dir.c | 32 +-
fs/jffs2/fs.c | 7 +-
fs/jffs2/os-linux.h | 2 +-
fs/jffs2/security.c | 1 +
fs/jffs2/xattr_trusted.c | 1 +
fs/jffs2/xattr_user.c | 1 +
fs/jfs/acl.c | 5 +-
fs/jfs/file.c | 9 +-
fs/jfs/ioctl.c | 2 +-
fs/jfs/jfs_acl.h | 3 +-
fs/jfs/jfs_inode.c | 2 +-
fs/jfs/jfs_inode.h | 2 +-
fs/jfs/namei.c | 21 +-
fs/jfs/xattr.c | 2 +
fs/kernfs/dir.c | 7 +-
fs/kernfs/inode.c | 15 +-
fs/kernfs/kernfs-internal.h | 5 +-
fs/libfs.c | 20 +-
fs/minix/bitmap.c | 2 +-
fs/minix/file.c | 7 +-
fs/minix/inode.c | 2 +-
fs/minix/namei.c | 25 +-
fs/mount.h | 10 -
fs/namei.c | 303 ++--
fs/namespace.c | 478 +++++-
fs/nfs/dir.c | 23 +-
fs/nfs/inode.c | 5 +-
fs/nfs/internal.h | 10 +-
fs/nfs/namespace.c | 7 +-
fs/nfs/nfs3_fs.h | 3 +-
fs/nfs/nfs3acl.c | 3 +-
fs/nfs/nfs4proc.c | 3 +
fs/nfsd/nfs2acl.c | 4 +-
fs/nfsd/nfs3acl.c | 4 +-
fs/nfsd/nfs4acl.c | 4 +-
fs/nfsd/nfs4recover.c | 6 +-
fs/nfsd/nfsfh.c | 2 +-
fs/nfsd/nfsproc.c | 2 +-
fs/nfsd/vfs.c | 47 +-
fs/nilfs2/inode.c | 13 +-
fs/nilfs2/ioctl.c | 2 +-
fs/nilfs2/namei.c | 20 +-
fs/nilfs2/nilfs.h | 4 +-
fs/notify/fanotify/fanotify_user.c | 2 +-
fs/notify/inotify/inotify_user.c | 3 +-
fs/ntfs/inode.c | 6 +-
fs/ntfs/inode.h | 3 +-
fs/ocfs2/acl.c | 5 +-
fs/ocfs2/acl.h | 3 +-
fs/ocfs2/dlmfs/dlmfs.c | 17 +-
fs/ocfs2/file.c | 13 +-
fs/ocfs2/file.h | 5 +-
fs/ocfs2/ioctl.c | 2 +-
fs/ocfs2/namei.c | 21 +-
fs/ocfs2/refcounttree.c | 4 +-
fs/ocfs2/xattr.c | 3 +
fs/omfs/dir.c | 13 +-
fs/omfs/file.c | 7 +-
fs/omfs/inode.c | 2 +-
fs/open.c | 50 +-
fs/orangefs/acl.c | 5 +-
fs/orangefs/inode.c | 15 +-
fs/orangefs/namei.c | 12 +-
fs/orangefs/orangefs-kernel.h | 7 +-
fs/orangefs/xattr.c | 1 +
fs/overlayfs/copy_up.c | 20 +-
fs/overlayfs/dir.c | 31 +-
fs/overlayfs/file.c | 6 +-
fs/overlayfs/inode.c | 21 +-
fs/overlayfs/overlayfs.h | 40 +-
fs/overlayfs/super.c | 19 +-
fs/overlayfs/util.c | 4 +-
fs/posix_acl.c | 78 +-
fs/proc/base.c | 24 +-
fs/proc/fd.c | 4 +-
fs/proc/fd.h | 3 +-
fs/proc/generic.c | 9 +-
fs/proc/internal.h | 2 +-
fs/proc/proc_net.c | 2 +-
fs/proc/proc_sysctl.c | 12 +-
fs/proc/root.c | 2 +-
fs/proc_namespace.c | 3 +
fs/ramfs/file-nommu.c | 9 +-
fs/ramfs/inode.c | 18 +-
fs/reiserfs/acl.h | 3 +-
fs/reiserfs/inode.c | 7 +-
fs/reiserfs/ioctl.c | 4 +-
fs/reiserfs/namei.c | 21 +-
fs/reiserfs/reiserfs.h | 3 +-
fs/reiserfs/xattr.c | 12 +-
fs/reiserfs/xattr.h | 2 +-
fs/reiserfs/xattr_acl.c | 7 +-
fs/reiserfs/xattr_security.c | 3 +-
fs/reiserfs/xattr_trusted.c | 3 +-
fs/reiserfs/xattr_user.c | 3 +-
fs/remap_range.c | 7 +-
fs/stat.c | 10 +-
fs/sysv/file.c | 7 +-
fs/sysv/ialloc.c | 2 +-
fs/sysv/itree.c | 2 +-
fs/sysv/namei.c | 21 +-
fs/tracefs/inode.c | 4 +-
fs/ubifs/dir.c | 29 +-
fs/ubifs/file.c | 5 +-
fs/ubifs/ioctl.c | 2 +-
fs/ubifs/ubifs.h | 3 +-
fs/ubifs/xattr.c | 1 +
fs/udf/file.c | 9 +-
fs/udf/ialloc.c | 2 +-
fs/udf/namei.c | 24 +-
fs/udf/symlink.c | 2 +-
fs/ufs/ialloc.c | 2 +-
fs/ufs/inode.c | 7 +-
fs/ufs/namei.c | 19 +-
fs/ufs/ufs.h | 3 +-
fs/utimes.c | 4 +-
fs/vboxsf/dir.c | 12 +-
fs/vboxsf/utils.c | 5 +-
fs/vboxsf/vfsmod.h | 3 +-
fs/verity/enable.c | 2 +-
fs/xattr.c | 136 +-
fs/xfs/xfs_acl.c | 5 +-
fs/xfs/xfs_acl.h | 3 +-
fs/xfs/xfs_ioctl.c | 4 +-
fs/xfs/xfs_iops.c | 55 +-
fs/xfs/xfs_xattr.c | 3 +-
fs/zonefs/super.c | 9 +-
include/linux/capability.h | 14 +-
include/linux/fs.h | 145 +-
include/linux/ima.h | 15 +-
include/linux/lsm_hook_defs.h | 15 +-
include/linux/lsm_hooks.h | 1 +
include/linux/mount.h | 7 +
include/linux/nfs_fs.h | 4 +-
include/linux/posix_acl.h | 15 +-
include/linux/posix_acl_xattr.h | 12 +-
include/linux/security.h | 44 +-
include/linux/syscalls.h | 3 +
include/linux/xattr.h | 30 +-
include/uapi/asm-generic/unistd.h | 4 +-
include/uapi/linux/mount.h | 27 +
ipc/mqueue.c | 8 +-
kernel/auditsc.c | 5 +-
kernel/bpf/inode.c | 13 +-
kernel/capability.c | 14 +-
kernel/cgroup/cgroup.c | 2 +-
kernel/sys.c | 2 +-
mm/madvise.c | 4 +-
mm/memcontrol.c | 2 +-
mm/mincore.c | 4 +-
mm/shmem.c | 45 +-
net/socket.c | 6 +-
net/unix/af_unix.c | 4 +-
security/apparmor/apparmorfs.c | 3 +-
security/apparmor/domain.c | 13 +-
security/apparmor/file.c | 5 +-
security/apparmor/lsm.c | 12 +-
security/commoncap.c | 46 +-
security/integrity/evm/evm_crypto.c | 11 +-
security/integrity/evm/evm_main.c | 4 +-
security/integrity/evm/evm_secfs.c | 2 +-
security/integrity/ima/ima.h | 19 +-
security/integrity/ima/ima_api.c | 10 +-
security/integrity/ima/ima_appraise.c | 22 +-
security/integrity/ima/ima_asymmetric_keys.c | 2 +-
security/integrity/ima/ima_main.c | 28 +-
security/integrity/ima/ima_policy.c | 17 +-
security/integrity/ima/ima_queue_keys.c | 2 +-
security/security.c | 25 +-
security/selinux/hooks.c | 22 +-
security/smack/smack_lsm.c | 18 +-
tools/include/uapi/asm-generic/unistd.h | 4 +-
tools/testing/selftests/Makefile | 1 +
.../selftests/mount_setattr/.gitignore | 1 +
.../testing/selftests/mount_setattr/Makefile | 7 +
tools/testing/selftests/mount_setattr/config | 1 +
.../mount_setattr/mount_setattr_test.c | 1424 +++++++++++++++++
327 files changed, 4165 insertions(+), 1551 deletions(-)
create mode 100644 tools/testing/selftests/mount_setattr/.gitignore
create mode 100644 tools/testing/selftests/mount_setattr/Makefile
create mode 100644 tools/testing/selftests/mount_setattr/config
create mode 100644 tools/testing/selftests/mount_setattr/mount_setattr_test.c
base-commit: 09162bc32c880a791c6c0668ce0745cf7958f576
--
2.29.2
^ permalink raw reply [flat|nested] 73+ messages in thread
* [PATCH v3 01/38] namespace: take lock_mount_hash() directly when changing flags
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
@ 2020-11-28 21:34 ` Christian Brauner
2020-12-01 10:31 ` Christoph Hellwig
2020-11-28 21:34 ` [PATCH v3 02/38] mount: make {lock,unlock}_mount_hash() static Christian Brauner
` (35 subsequent siblings)
36 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:34 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
Changing mount options always ends up taking lock_mount_hash() but when
MNT_READONLY is requested and neither the mount nor the superblock are
MNT_READONLY we end up taking the lock, dropping it, and retaking it to change
the other mount attributes. Instead, let's acquire the lock once when changing
the mount attributes. This simplifies the locking in these codepath, makes them
easier to reason about and avoids having to reacquire the lock right after
dropping it.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Remove pointless __mnt_unmake_readonly() helper.
- Even though Christoph suggested to lockdep_assert_held() into places that
require {lock,unlock}_mount_hash() it seems that seqlock's don't support
it.
/* v3 */
unchanged
---
fs/namespace.c | 22 ++++++++--------------
1 file changed, 8 insertions(+), 14 deletions(-)
diff --git a/fs/namespace.c b/fs/namespace.c
index cebaa3e81794..f183161833ad 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -463,7 +463,6 @@ static int mnt_make_readonly(struct mount *mnt)
{
int ret = 0;
- lock_mount_hash();
mnt->mnt.mnt_flags |= MNT_WRITE_HOLD;
/*
* After storing MNT_WRITE_HOLD, we'll read the counters. This store
@@ -497,18 +496,9 @@ static int mnt_make_readonly(struct mount *mnt)
*/
smp_wmb();
mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD;
- unlock_mount_hash();
return ret;
}
-static int __mnt_unmake_readonly(struct mount *mnt)
-{
- lock_mount_hash();
- mnt->mnt.mnt_flags &= ~MNT_READONLY;
- unlock_mount_hash();
- return 0;
-}
-
int sb_prepare_remount_readonly(struct super_block *sb)
{
struct mount *mnt;
@@ -2508,7 +2498,8 @@ static int change_mount_ro_state(struct mount *mnt, unsigned int mnt_flags)
if (readonly_request)
return mnt_make_readonly(mnt);
- return __mnt_unmake_readonly(mnt);
+ mnt->mnt.mnt_flags &= ~MNT_READONLY;
+ return 0;
}
/*
@@ -2517,11 +2508,9 @@ static int change_mount_ro_state(struct mount *mnt, unsigned int mnt_flags)
*/
static void set_mount_attributes(struct mount *mnt, unsigned int mnt_flags)
{
- lock_mount_hash();
mnt_flags |= mnt->mnt.mnt_flags & ~MNT_USER_SETTABLE_MASK;
mnt->mnt.mnt_flags = mnt_flags;
touch_mnt_namespace(mnt->mnt_ns);
- unlock_mount_hash();
}
static void mnt_warn_timestamp_expiry(struct path *mountpoint, struct vfsmount *mnt)
@@ -2567,9 +2556,11 @@ static int do_reconfigure_mnt(struct path *path, unsigned int mnt_flags)
return -EPERM;
down_write(&sb->s_umount);
+ lock_mount_hash();
ret = change_mount_ro_state(mnt, mnt_flags);
if (ret == 0)
set_mount_attributes(mnt, mnt_flags);
+ unlock_mount_hash();
up_write(&sb->s_umount);
mnt_warn_timestamp_expiry(path, &mnt->mnt);
@@ -2610,8 +2601,11 @@ static int do_remount(struct path *path, int ms_flags, int sb_flags,
err = -EPERM;
if (ns_capable(sb->s_user_ns, CAP_SYS_ADMIN)) {
err = reconfigure_super(fc);
- if (!err)
+ if (!err) {
+ lock_mount_hash();
set_mount_attributes(mnt, mnt_flags);
+ unlock_mount_hash();
+ }
}
up_write(&sb->s_umount);
}
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 02/38] mount: make {lock,unlock}_mount_hash() static
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
2020-11-28 21:34 ` [PATCH v3 01/38] namespace: take lock_mount_hash() directly when changing flags Christian Brauner
@ 2020-11-28 21:34 ` Christian Brauner
2020-12-01 10:32 ` Christoph Hellwig
2020-11-28 21:34 ` [PATCH v3 03/38] namespace: only take read lock in do_reconfigure_mnt() Christian Brauner
` (34 subsequent siblings)
36 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:34 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
The lock_mount_hash() and unlock_mount_hash() helpers are never called outside a
single file. Remove them from the header and make them static to reflect this
fact. There's no need to have them callable from other places right now, as
Christoph observed.
Suggested-by: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Add a patch to make {lock,unlock)_mount_hash() static.
/* v3 */
unchanged
---
fs/mount.h | 10 ----------
fs/namespace.c | 10 ++++++++++
2 files changed, 10 insertions(+), 10 deletions(-)
diff --git a/fs/mount.h b/fs/mount.h
index c7abb7b394d8..562d96d57bad 100644
--- a/fs/mount.h
+++ b/fs/mount.h
@@ -125,16 +125,6 @@ static inline void get_mnt_ns(struct mnt_namespace *ns)
extern seqlock_t mount_lock;
-static inline void lock_mount_hash(void)
-{
- write_seqlock(&mount_lock);
-}
-
-static inline void unlock_mount_hash(void)
-{
- write_sequnlock(&mount_lock);
-}
-
struct proc_mounts {
struct mnt_namespace *ns;
struct path root;
diff --git a/fs/namespace.c b/fs/namespace.c
index f183161833ad..798bbf4f48ad 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -87,6 +87,16 @@ EXPORT_SYMBOL_GPL(fs_kobj);
*/
__cacheline_aligned_in_smp DEFINE_SEQLOCK(mount_lock);
+static inline void lock_mount_hash(void)
+{
+ write_seqlock(&mount_lock);
+}
+
+static inline void unlock_mount_hash(void)
+{
+ write_sequnlock(&mount_lock);
+}
+
static inline struct hlist_head *m_hash(struct vfsmount *mnt, struct dentry *dentry)
{
unsigned long tmp = ((unsigned long)mnt / L1_CACHE_BYTES);
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 03/38] namespace: only take read lock in do_reconfigure_mnt()
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
2020-11-28 21:34 ` [PATCH v3 01/38] namespace: take lock_mount_hash() directly when changing flags Christian Brauner
2020-11-28 21:34 ` [PATCH v3 02/38] mount: make {lock,unlock}_mount_hash() static Christian Brauner
@ 2020-11-28 21:34 ` Christian Brauner
2020-12-01 10:32 ` Christoph Hellwig
2020-11-28 21:34 ` [PATCH v3 04/38] fs: add mount_setattr() Christian Brauner
` (33 subsequent siblings)
36 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:34 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
do_reconfigure_mnt() used to take the down_write(&sb->s_umount) lock
which seems unnecessary since we're not changing the superblock. We're
only checking whether it is already read-only. Setting other mount
attributes is protected by lock_mount_hash() afaict and not by s_umount.
So I think the history of down_write(&sb->s_umount) lock being taken
when setting mount attributes dates back to the introduction of
MNT_READONLY in [2]. Afaict, this introduced the concept of having
read-only mounts in contrast to just having a read-only superblock. When
it got introduced it was simply plumbed into do_remount() which already
took down_write(&sb->s_umount) because it was only used to actually
change the superblock before [2]. Afaict, it would've already been
possible back then to only use down_read(&sb->s_umount) for
MS_BIND | MS_REMOUNT since actual mount options were protected by
the vfsmount lock already. But that would've meant special casing the
locking for MS_BIND | MS_REMOUNT in do_remount() which people might not
have considered worth it.
Then in [1] MS_BIND | MS_REMOUNT mount option changes were split out of
do_remount() into do_reconfigure_mnt() but the down_write(&sb->s_umount)
lock was simply copied over.
Now that we have this be a separate helper only take
the down_read(&sb->s_umount) lock since we're only interested in
checking whether the super block is currently read-only and blocking any
writers from changing it. Essentially, checking that the super block is
read-only has the advantage that we can avoid having to go into the
slowpath and through MNT_WRITE_HOLD and can simply set the read-only
flag on the mount in set_mount_attributes().
[1]: commit 43f5e655eff7 ("vfs: Separate changing mount flags full remount")
[2]: commit 2e4b7fcd9260 ("[PATCH] r/o bind mounts: honor mount writer counts at remount")
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
fs/namespace.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/fs/namespace.c b/fs/namespace.c
index 798bbf4f48ad..8497d149ecaa 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -2512,10 +2512,6 @@ static int change_mount_ro_state(struct mount *mnt, unsigned int mnt_flags)
return 0;
}
-/*
- * Update the user-settable attributes on a mount. The caller must hold
- * sb->s_umount for writing.
- */
static void set_mount_attributes(struct mount *mnt, unsigned int mnt_flags)
{
mnt_flags |= mnt->mnt.mnt_flags & ~MNT_USER_SETTABLE_MASK;
@@ -2565,13 +2561,17 @@ static int do_reconfigure_mnt(struct path *path, unsigned int mnt_flags)
if (!can_change_locked_flags(mnt, mnt_flags))
return -EPERM;
- down_write(&sb->s_umount);
+ /*
+ * We're only checking whether the superblock is read-only not changing
+ * it, so only take down_read(&sb->s_umount).
+ */
+ down_read(&sb->s_umount);
lock_mount_hash();
ret = change_mount_ro_state(mnt, mnt_flags);
if (ret == 0)
set_mount_attributes(mnt, mnt_flags);
unlock_mount_hash();
- up_write(&sb->s_umount);
+ up_read(&sb->s_umount);
mnt_warn_timestamp_expiry(path, &mnt->mnt);
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 04/38] fs: add mount_setattr()
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (2 preceding siblings ...)
2020-11-28 21:34 ` [PATCH v3 03/38] namespace: only take read lock in do_reconfigure_mnt() Christian Brauner
@ 2020-11-28 21:34 ` Christian Brauner
2020-12-01 10:49 ` Christoph Hellwig
2020-11-28 21:34 ` [PATCH v3 05/38] tests: add mount_setattr() selftests Christian Brauner
` (32 subsequent siblings)
36 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:34 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
This implements the missing mount_setattr() syscall. While the new mount api
allows to change the properties of a superblock there is currently no way to
change the properties of a mount or a mount tree using file descriptors which
the new mount api is based on. In addition the old mount api has the restriction
that mount options cannot be applied recursively. This hasn't changed since
changing mount options on a per-mount basis was implemented in [1] and has been
a frequent request not just for convenience but also for security reasons.
The legacy mount syscall is unable to accommodate this behavior without
introducing a whole new set of flags because MS_REC | MS_REMOUNT | MS_BIND |
MS_RDONLY | MS_NOEXEC | [...] only apply the mount option to the topmost mount.
Changing MS_REC to apply to the whole mount tree would mean introducing a
significant uapi change and would likely cause significant regressions.
The new mount_setattr() syscall allows to recursively clear and set mount
options in one shot. Multiple calls to change mount options requesting the same
changes are idempotent:
int mount_setattr(int dfd, const char *path, unsigned flags,
struct mount_attr *uattr, size_t usize);
Flags to modify path resolution behavior are specified in the @flags argument.
Currently, AT_EMPTY_PATH, AT_RECURSIVE, AT_SYMLINK_NOFOLLOW, and AT_NO_AUTOMOUNT
are supported. If useful, additional lookup flags to restrict path resolution as
introduced with openat2() might be supported in the future.
The mount_setattr() syscall can be expected to grow over time and is designed
with extensibility in mind. It follows the extensible syscall pattern we have
used with other syscalls such as openat2(), clone3(), sched_{set,get}attr(), and
others.
The set of mount options is passed in the uapi struct mount_attr which currently
has the following layout:
struct mount_attr {
__u64 attr_set;
__u64 attr_clr;
__u32 propagation;
};
The @attr_set and @attr_clr members are used to clear and set mount options.
This way a user can e.g. request that a set of flags is to be raised such as
turning mounts readonly by raising MOUNT_ATTR_RDONLY in @attr_set while at the
same time requesting that another set of flags is to be lowered such as removing
noexec from a mount tree by specifying MOUNT_ATTR_NOEXEC in @attr_clr.
Note, since the MOUNT_ATTR_<atime> values are an enum starting from 0, not a
bitmap, users wanting to transition to a different atime setting cannot simply
specify the atime setting in @attr_set, but must also specify MOUNT_ATTR__ATIME
in the @attr_clr field. So we ensure that MOUNT_ATTR__ATIME can't be partially
set in @attr_clr and that @attr_set can't have any atime bits set if
MOUNT_ATTR__ATIME isn't set in @attr_clr.
The @propagation field lets callers specify the propagation type of a mount
tree. Propagation is a single property that has four different settings and as
such is not really a flag argument but an enum. Specifically, it would be
unclear what setting and clearing propagation settings in combination would
amount to. The legacy mount() syscall thus forbids the combination of multiple
propagation settings too. The goal is to keep the semantics of mount propagation
somewhat simple as they are overly complex as it is.
[1]: commit 2e4b7fcd9260 ("[PATCH] r/o bind mounts: honor mount writer counts at remount")
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-api@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Split into multiple helpers.
/* v3 */
- kernel test robot <lkp@intel.com>:
- Fix unknown __u64 type by including linux/types.h in linux/mount.h.
---
arch/alpha/kernel/syscalls/syscall.tbl | 1 +
arch/arm/tools/syscall.tbl | 1 +
arch/arm64/include/asm/unistd32.h | 2 +
arch/ia64/kernel/syscalls/syscall.tbl | 1 +
arch/m68k/kernel/syscalls/syscall.tbl | 1 +
arch/microblaze/kernel/syscalls/syscall.tbl | 1 +
arch/mips/kernel/syscalls/syscall_n32.tbl | 1 +
arch/mips/kernel/syscalls/syscall_n64.tbl | 1 +
arch/mips/kernel/syscalls/syscall_o32.tbl | 1 +
arch/parisc/kernel/syscalls/syscall.tbl | 1 +
arch/powerpc/kernel/syscalls/syscall.tbl | 1 +
arch/s390/kernel/syscalls/syscall.tbl | 1 +
arch/sh/kernel/syscalls/syscall.tbl | 1 +
arch/sparc/kernel/syscalls/syscall.tbl | 1 +
arch/x86/entry/syscalls/syscall_32.tbl | 1 +
arch/x86/entry/syscalls/syscall_64.tbl | 1 +
arch/xtensa/kernel/syscalls/syscall.tbl | 1 +
fs/internal.h | 8 +
fs/namespace.c | 327 ++++++++++++++++++--
include/linux/syscalls.h | 3 +
include/uapi/asm-generic/unistd.h | 4 +-
include/uapi/linux/mount.h | 24 ++
tools/include/uapi/asm-generic/unistd.h | 4 +-
23 files changed, 362 insertions(+), 26 deletions(-)
diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl
index ee7b01bb7346..24d8709624b8 100644
--- a/arch/alpha/kernel/syscalls/syscall.tbl
+++ b/arch/alpha/kernel/syscalls/syscall.tbl
@@ -480,3 +480,4 @@
548 common pidfd_getfd sys_pidfd_getfd
549 common faccessat2 sys_faccessat2
550 common process_madvise sys_process_madvise
+551 common mount_setattr sys_mount_setattr
diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl
index d056a548358e..e3785513d445 100644
--- a/arch/arm/tools/syscall.tbl
+++ b/arch/arm/tools/syscall.tbl
@@ -454,3 +454,4 @@
438 common pidfd_getfd sys_pidfd_getfd
439 common faccessat2 sys_faccessat2
440 common process_madvise sys_process_madvise
+441 common mount_setattr sys_mount_setattr
diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h
index 107f08e03b9f..78af754e070a 100644
--- a/arch/arm64/include/asm/unistd32.h
+++ b/arch/arm64/include/asm/unistd32.h
@@ -889,6 +889,8 @@ __SYSCALL(__NR_pidfd_getfd, sys_pidfd_getfd)
__SYSCALL(__NR_faccessat2, sys_faccessat2)
#define __NR_process_madvise 440
__SYSCALL(__NR_process_madvise, sys_process_madvise)
+#define __NR_mount_setattr 441
+__SYSCALL(__NR_mount_setattr, sys_mount_setattr)
/*
* Please add new compat syscalls above this comment and update
diff --git a/arch/ia64/kernel/syscalls/syscall.tbl b/arch/ia64/kernel/syscalls/syscall.tbl
index b96ed8b8a508..f7d4b1f55be0 100644
--- a/arch/ia64/kernel/syscalls/syscall.tbl
+++ b/arch/ia64/kernel/syscalls/syscall.tbl
@@ -361,3 +361,4 @@
438 common pidfd_getfd sys_pidfd_getfd
439 common faccessat2 sys_faccessat2
440 common process_madvise sys_process_madvise
+441 common mount_setattr sys_mount_setattr
diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl
index 625fb6d32842..e96e9c6a6ffa 100644
--- a/arch/m68k/kernel/syscalls/syscall.tbl
+++ b/arch/m68k/kernel/syscalls/syscall.tbl
@@ -440,3 +440,4 @@
438 common pidfd_getfd sys_pidfd_getfd
439 common faccessat2 sys_faccessat2
440 common process_madvise sys_process_madvise
+441 common mount_setattr sys_mount_setattr
diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl
index aae729c95cf9..6538f075a18e 100644
--- a/arch/microblaze/kernel/syscalls/syscall.tbl
+++ b/arch/microblaze/kernel/syscalls/syscall.tbl
@@ -446,3 +446,4 @@
438 common pidfd_getfd sys_pidfd_getfd
439 common faccessat2 sys_faccessat2
440 common process_madvise sys_process_madvise
+441 common mount_setattr sys_mount_setattr
diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl
index 32817c954435..64d129db1aa7 100644
--- a/arch/mips/kernel/syscalls/syscall_n32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n32.tbl
@@ -379,3 +379,4 @@
438 n32 pidfd_getfd sys_pidfd_getfd
439 n32 faccessat2 sys_faccessat2
440 n32 process_madvise sys_process_madvise
+441 n32 mount_setattr sys_mount_setattr
diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl
index 9e4ea3c31b1c..94b24e6b2608 100644
--- a/arch/mips/kernel/syscalls/syscall_n64.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n64.tbl
@@ -355,3 +355,4 @@
438 n64 pidfd_getfd sys_pidfd_getfd
439 n64 faccessat2 sys_faccessat2
440 n64 process_madvise sys_process_madvise
+441 n64 mount_setattr sys_mount_setattr
diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl
index 29f5f28cf5ce..eae522306767 100644
--- a/arch/mips/kernel/syscalls/syscall_o32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_o32.tbl
@@ -428,3 +428,4 @@
438 o32 pidfd_getfd sys_pidfd_getfd
439 o32 faccessat2 sys_faccessat2
440 o32 process_madvise sys_process_madvise
+441 o32 mount_setattr sys_mount_setattr
diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl
index f375ea528e59..c7e25f1d219f 100644
--- a/arch/parisc/kernel/syscalls/syscall.tbl
+++ b/arch/parisc/kernel/syscalls/syscall.tbl
@@ -438,3 +438,4 @@
438 common pidfd_getfd sys_pidfd_getfd
439 common faccessat2 sys_faccessat2
440 common process_madvise sys_process_madvise
+441 common mount_setattr sys_mount_setattr
diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
index 1275daec7fec..0b309ef64e91 100644
--- a/arch/powerpc/kernel/syscalls/syscall.tbl
+++ b/arch/powerpc/kernel/syscalls/syscall.tbl
@@ -530,3 +530,4 @@
438 common pidfd_getfd sys_pidfd_getfd
439 common faccessat2 sys_faccessat2
440 common process_madvise sys_process_madvise
+441 common mount_setattr sys_mount_setattr
diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl
index 28c168000483..0b30398fee42 100644
--- a/arch/s390/kernel/syscalls/syscall.tbl
+++ b/arch/s390/kernel/syscalls/syscall.tbl
@@ -443,3 +443,4 @@
438 common pidfd_getfd sys_pidfd_getfd sys_pidfd_getfd
439 common faccessat2 sys_faccessat2 sys_faccessat2
440 common process_madvise sys_process_madvise sys_process_madvise
+441 common mount_setattr sys_mount_setattr sys_mount_setattr
diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl
index 783738448ff5..8e4949c5b740 100644
--- a/arch/sh/kernel/syscalls/syscall.tbl
+++ b/arch/sh/kernel/syscalls/syscall.tbl
@@ -443,3 +443,4 @@
438 common pidfd_getfd sys_pidfd_getfd
439 common faccessat2 sys_faccessat2
440 common process_madvise sys_process_madvise
+441 common mount_setattr sys_mount_setattr
diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl
index 78160260991b..409f21a650b8 100644
--- a/arch/sparc/kernel/syscalls/syscall.tbl
+++ b/arch/sparc/kernel/syscalls/syscall.tbl
@@ -486,3 +486,4 @@
438 common pidfd_getfd sys_pidfd_getfd
439 common faccessat2 sys_faccessat2
440 common process_madvise sys_process_madvise
+441 common mount_setattr sys_mount_setattr
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index 0d0667a9fbd7..2a694420f6cd 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -445,3 +445,4 @@
438 i386 pidfd_getfd sys_pidfd_getfd
439 i386 faccessat2 sys_faccessat2
440 i386 process_madvise sys_process_madvise
+441 i386 mount_setattr sys_mount_setattr
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index 379819244b91..4d594d0246c1 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -362,6 +362,7 @@
438 common pidfd_getfd sys_pidfd_getfd
439 common faccessat2 sys_faccessat2
440 common process_madvise sys_process_madvise
+441 common mount_setattr sys_mount_setattr
#
# Due to a historical design error, certain syscalls are numbered differently
diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl
index b070f272995d..a650dc05593d 100644
--- a/arch/xtensa/kernel/syscalls/syscall.tbl
+++ b/arch/xtensa/kernel/syscalls/syscall.tbl
@@ -411,3 +411,4 @@
438 common pidfd_getfd sys_pidfd_getfd
439 common faccessat2 sys_faccessat2
440 common process_madvise sys_process_madvise
+441 common mount_setattr sys_mount_setattr
diff --git a/fs/internal.h b/fs/internal.h
index a7cd0f64faa4..a5a6c470dc07 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -82,6 +82,14 @@ int may_linkat(struct path *link);
/*
* namespace.c
*/
+struct mount_kattr {
+ unsigned int attr_set;
+ unsigned int attr_clr;
+ unsigned int propagation;
+ unsigned int lookup_flags;
+ bool recurse;
+};
+
extern struct vfsmount *lookup_mnt(const struct path *);
extern int finish_automount(struct vfsmount *, struct path *);
diff --git a/fs/namespace.c b/fs/namespace.c
index 8497d149ecaa..f9ea31b7eb7f 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -469,10 +469,8 @@ void mnt_drop_write_file(struct file *file)
}
EXPORT_SYMBOL(mnt_drop_write_file);
-static int mnt_make_readonly(struct mount *mnt)
+static inline int mnt_hold_writers(struct mount *mnt)
{
- int ret = 0;
-
mnt->mnt.mnt_flags |= MNT_WRITE_HOLD;
/*
* After storing MNT_WRITE_HOLD, we'll read the counters. This store
@@ -497,15 +495,29 @@ static int mnt_make_readonly(struct mount *mnt)
* we're counting up here.
*/
if (mnt_get_writers(mnt) > 0)
- ret = -EBUSY;
- else
- mnt->mnt.mnt_flags |= MNT_READONLY;
+ return -EBUSY;
+
+ return 0;
+}
+
+static inline void mnt_unhold_writers(struct mount *mnt)
+{
/*
* MNT_READONLY must become visible before ~MNT_WRITE_HOLD, so writers
* that become unheld will see MNT_READONLY.
*/
smp_wmb();
mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD;
+}
+
+static int mnt_make_readonly(struct mount *mnt)
+{
+ int ret;
+
+ ret = mnt_hold_writers(mnt);
+ if (!ret)
+ mnt->mnt.mnt_flags |= MNT_READONLY;
+ mnt_unhold_writers(mnt);
return ret;
}
@@ -3438,6 +3450,33 @@ SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name,
return ret;
}
+static int build_attr_flags(unsigned int attr_flags, unsigned int *flags)
+{
+ unsigned int aflags = 0;
+
+ if (attr_flags & ~(MOUNT_ATTR_RDONLY |
+ MOUNT_ATTR_NOSUID |
+ MOUNT_ATTR_NODEV |
+ MOUNT_ATTR_NOEXEC |
+ MOUNT_ATTR__ATIME |
+ MOUNT_ATTR_NODIRATIME))
+ return -EINVAL;
+
+ if (attr_flags & MOUNT_ATTR_RDONLY)
+ aflags |= MNT_READONLY;
+ if (attr_flags & MOUNT_ATTR_NOSUID)
+ aflags |= MNT_NOSUID;
+ if (attr_flags & MOUNT_ATTR_NODEV)
+ aflags |= MNT_NODEV;
+ if (attr_flags & MOUNT_ATTR_NOEXEC)
+ aflags |= MNT_NOEXEC;
+ if (attr_flags & MOUNT_ATTR_NODIRATIME)
+ aflags |= MNT_NODIRATIME;
+
+ *flags = aflags;
+ return 0;
+}
+
/*
* Create a kernel mount representation for a new, prepared superblock
* (specified by fs_fd) and attach to an open_tree-like file descriptor.
@@ -3460,24 +3499,9 @@ SYSCALL_DEFINE3(fsmount, int, fs_fd, unsigned int, flags,
if ((flags & ~(FSMOUNT_CLOEXEC)) != 0)
return -EINVAL;
- if (attr_flags & ~(MOUNT_ATTR_RDONLY |
- MOUNT_ATTR_NOSUID |
- MOUNT_ATTR_NODEV |
- MOUNT_ATTR_NOEXEC |
- MOUNT_ATTR__ATIME |
- MOUNT_ATTR_NODIRATIME))
- return -EINVAL;
-
- if (attr_flags & MOUNT_ATTR_RDONLY)
- mnt_flags |= MNT_READONLY;
- if (attr_flags & MOUNT_ATTR_NOSUID)
- mnt_flags |= MNT_NOSUID;
- if (attr_flags & MOUNT_ATTR_NODEV)
- mnt_flags |= MNT_NODEV;
- if (attr_flags & MOUNT_ATTR_NOEXEC)
- mnt_flags |= MNT_NOEXEC;
- if (attr_flags & MOUNT_ATTR_NODIRATIME)
- mnt_flags |= MNT_NODIRATIME;
+ ret = build_attr_flags(attr_flags, &mnt_flags);
+ if (ret)
+ return ret;
switch (attr_flags & MOUNT_ATTR__ATIME) {
case MOUNT_ATTR_STRICTATIME:
@@ -3785,6 +3809,261 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root,
return error;
}
+static unsigned int recalc_flags(struct mount_kattr *kattr, struct mount *mnt)
+{
+ unsigned int flags = mnt->mnt.mnt_flags;
+
+ /* flags to clear */
+ flags &= ~kattr->attr_clr;
+ /* flags to raise */
+ flags |= kattr->attr_set;
+
+ return flags;
+}
+
+static struct mount *mount_setattr_prepare(struct mount_kattr *kattr,
+ struct mount *mnt, int *err)
+{
+ struct mount *m = mnt, *last = NULL;
+
+ if (!is_mounted(&m->mnt)) {
+ *err = -EINVAL;
+ goto out;
+ }
+
+ if (!(mnt_has_parent(m) ? check_mnt(m) : is_anon_ns(m->mnt_ns))) {
+ *err = -EINVAL;
+ goto out;
+ }
+
+ do {
+ unsigned int flags;
+
+ flags = recalc_flags(kattr, m);
+ if (!can_change_locked_flags(m, flags)) {
+ *err = -EPERM;
+ goto out;
+ }
+
+ last = m;
+
+ if ((kattr->attr_set & MNT_READONLY) &&
+ !(m->mnt.mnt_flags & MNT_READONLY)) {
+ *err = mnt_hold_writers(m);
+ if (*err)
+ goto out;
+ }
+ } while (kattr->recurse && (m = next_mnt(m, mnt)));
+
+out:
+ return last;
+}
+
+static void mount_setattr_commit(struct mount_kattr *kattr, struct mount *mnt,
+ struct mount *last, int err)
+{
+ struct mount *m = mnt;
+
+ do {
+ if (!err) {
+ unsigned int flags;
+
+ flags = recalc_flags(kattr, m);
+ WRITE_ONCE(m->mnt.mnt_flags, flags);
+ }
+
+ /*
+ * We either set MNT_READONLY above so make it visible
+ * before ~MNT_WRITE_HOLD or we failed to recursively
+ * apply mount options.
+ */
+ if ((kattr->attr_set & MNT_READONLY) &&
+ (m->mnt.mnt_flags & MNT_WRITE_HOLD))
+ mnt_unhold_writers(m);
+
+ if (!err && kattr->propagation)
+ change_mnt_propagation(m, kattr->propagation);
+
+ /*
+ * On failure, only cleanup until we found the first mount we
+ * failed to handle.
+ */
+ if (err && m == last)
+ break;
+ } while (kattr->recurse && (m = next_mnt(m, mnt)));
+
+ if (!err)
+ touch_mnt_namespace(mnt->mnt_ns);
+}
+
+static int do_mount_setattr(struct path *path, struct mount_kattr *kattr)
+{
+ struct mount *mnt = real_mount(path->mnt), *last = NULL;
+ int err = 0;
+
+ if (path->dentry != mnt->mnt.mnt_root)
+ return -EINVAL;
+
+ if (kattr->propagation) {
+ /*
+ * Only take namespace_lock() if we're actually changing
+ * propagation.
+ */
+ namespace_lock();
+ if (kattr->propagation == MS_SHARED) {
+ err = invent_group_ids(mnt, kattr->recurse);
+ if (err) {
+ namespace_unlock();
+ return err;
+ }
+ }
+ }
+
+ lock_mount_hash();
+
+ /*
+ * Get the mount tree in a shape where we can change mount properties
+ * without failure.
+ */
+ last = mount_setattr_prepare(kattr, mnt, &err);
+ if (last) /* Commit all changes or revert to the old state. */
+ mount_setattr_commit(kattr, mnt, last, err);
+
+ unlock_mount_hash();
+
+ if (kattr->propagation) {
+ namespace_unlock();
+ if (err)
+ cleanup_group_ids(mnt, NULL);
+ }
+
+ return err;
+}
+
+static int build_mount_kattr(const struct mount_attr *attr,
+ struct mount_kattr *kattr, unsigned int flags)
+{
+ unsigned int lookup_flags = LOOKUP_AUTOMOUNT | LOOKUP_FOLLOW;
+
+ if (flags & AT_NO_AUTOMOUNT)
+ lookup_flags &= ~LOOKUP_AUTOMOUNT;
+ if (flags & AT_SYMLINK_NOFOLLOW)
+ lookup_flags &= ~LOOKUP_FOLLOW;
+ if (flags & AT_EMPTY_PATH)
+ lookup_flags |= LOOKUP_EMPTY;
+
+ *kattr = (struct mount_kattr){
+ .lookup_flags = lookup_flags,
+ .recurse = !!(flags & AT_RECURSIVE),
+ };
+
+ switch (attr->propagation) {
+ case MAKE_PROPAGATION_UNCHANGED:
+ kattr->propagation = 0;
+ break;
+ case MAKE_PROPAGATION_UNBINDABLE:
+ kattr->propagation = MS_UNBINDABLE;
+ break;
+ case MAKE_PROPAGATION_PRIVATE:
+ kattr->propagation = MS_PRIVATE;
+ break;
+ case MAKE_PROPAGATION_DEPENDENT:
+ kattr->propagation = MS_SLAVE;
+ break;
+ case MAKE_PROPAGATION_SHARED:
+ kattr->propagation = MS_SHARED;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (upper_32_bits(attr->attr_set))
+ return -EINVAL;
+ if (build_attr_flags(lower_32_bits(attr->attr_set), &kattr->attr_set))
+ return -EINVAL;
+
+ if (upper_32_bits(attr->attr_clr))
+ return -EINVAL;
+ if (build_attr_flags(lower_32_bits(attr->attr_clr), &kattr->attr_clr))
+ return -EINVAL;
+
+ /*
+ * Since the MOUNT_ATTR_<atime> values are an enum, not a bitmap, users
+ * wanting to transition to a different atime setting cannot simply
+ * specify the atime setting in @attr_set, but must also specify
+ * MOUNT_ATTR__ATIME in the @attr_clr field.
+ * So ensure that MOUNT_ATTR__ATIME can't be partially set in
+ * @attr_clr and that @attr_set can't have any atime bits set if
+ * MOUNT_ATTR__ATIME isn't set in @attr_clr.
+ */
+ if (!(attr->attr_clr & MOUNT_ATTR__ATIME) && (attr->attr_set & MOUNT_ATTR__ATIME))
+ return -EINVAL;
+ else if ((attr->attr_clr & MOUNT_ATTR__ATIME) &&
+ ((attr->attr_clr & MOUNT_ATTR__ATIME) != MOUNT_ATTR__ATIME))
+ return -EINVAL;
+
+ if (attr->attr_clr & MOUNT_ATTR__ATIME) {
+ /* Clear all previous time settings as they are mutually exclusive. */
+ kattr->attr_clr |= MNT_RELATIME | MNT_NOATIME;
+ switch (attr->attr_set & MOUNT_ATTR__ATIME) {
+ case MOUNT_ATTR_RELATIME:
+ kattr->attr_set |= MNT_RELATIME;
+ break;
+ case MOUNT_ATTR_NOATIME:
+ kattr->attr_set |= MNT_NOATIME;
+ break;
+ case MOUNT_ATTR_STRICTATIME:
+ break;
+ default:
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+SYSCALL_DEFINE5(mount_setattr, int, dfd, const char __user *, path, unsigned int, flags,
+ struct mount_attr __user *, uattr, size_t, usize)
+{
+ int err;
+ struct path target;
+ struct mount_attr attr;
+ struct mount_kattr kattr;
+
+ BUILD_BUG_ON(sizeof(struct mount_attr) < MOUNT_ATTR_SIZE_VER0);
+ BUILD_BUG_ON(sizeof(struct mount_attr) != MOUNT_ATTR_SIZE_LATEST);
+
+ if (flags & ~(AT_EMPTY_PATH | AT_RECURSIVE | AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT))
+ return -EINVAL;
+
+ if (unlikely(usize > PAGE_SIZE))
+ return -E2BIG;
+ if (unlikely(usize < MOUNT_ATTR_SIZE_VER0))
+ return -EINVAL;
+
+ if (!may_mount())
+ return -EPERM;
+
+ err = copy_struct_from_user(&attr, sizeof(attr), uattr, usize);
+ if (err)
+ return err;
+
+ if (attr.attr_set == 0 && attr.attr_clr == 0 && attr.propagation == 0)
+ return 0;
+
+ err = build_mount_kattr(&attr, &kattr, flags);
+ if (err)
+ return err;
+
+ err = user_path_at(dfd, path, kattr.lookup_flags, &target);
+ if (err)
+ return err;
+
+ err = do_mount_setattr(&target, &kattr);
+ path_put(&target);
+ return err;
+}
+
static void __init init_mount_tree(void)
{
struct vfsmount *mnt;
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 37bea07c12f2..a62d5904fb6a 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -68,6 +68,7 @@ union bpf_attr;
struct io_uring_params;
struct clone_args;
struct open_how;
+struct mount_attr;
#include <linux/types.h>
#include <linux/aio_abi.h>
@@ -999,6 +1000,8 @@ asmlinkage long sys_open_tree(int dfd, const char __user *path, unsigned flags);
asmlinkage long sys_move_mount(int from_dfd, const char __user *from_path,
int to_dfd, const char __user *to_path,
unsigned int ms_flags);
+asmlinkage long sys_mount_setattr(int dfd, const char __user *path, unsigned int flags,
+ struct mount_attr __user *uattr, size_t usize);
asmlinkage long sys_fsopen(const char __user *fs_name, unsigned int flags);
asmlinkage long sys_fsconfig(int fs_fd, unsigned int cmd, const char __user *key,
const void __user *value, int aux);
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index 2056318988f7..0517f36fe783 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -859,9 +859,11 @@ __SYSCALL(__NR_pidfd_getfd, sys_pidfd_getfd)
__SYSCALL(__NR_faccessat2, sys_faccessat2)
#define __NR_process_madvise 440
__SYSCALL(__NR_process_madvise, sys_process_madvise)
+#define __NR_mount_setattr 441
+__SYSCALL(__NR_mount_setattr, sys_mount_setattr)
#undef __NR_syscalls
-#define __NR_syscalls 441
+#define __NR_syscalls 442
/*
* 32 bit systems traditionally used different
diff --git a/include/uapi/linux/mount.h b/include/uapi/linux/mount.h
index dd8306ea336c..fba42b4bfc1c 100644
--- a/include/uapi/linux/mount.h
+++ b/include/uapi/linux/mount.h
@@ -1,6 +1,8 @@
#ifndef _UAPI_LINUX_MOUNT_H
#define _UAPI_LINUX_MOUNT_H
+#include <linux/types.h>
+
/*
* These are the fs-independent mount-flags: up to 32 flags are supported
*
@@ -118,4 +120,26 @@ enum fsconfig_command {
#define MOUNT_ATTR_STRICTATIME 0x00000020 /* - Always perform atime updates */
#define MOUNT_ATTR_NODIRATIME 0x00000080 /* Do not update directory access times */
+/*
+ * mount_setattr()
+ */
+struct mount_attr {
+ __u64 attr_set;
+ __u64 attr_clr;
+ __u64 propagation;
+};
+
+/* Change propagation through mount_setattr(). */
+enum propagation_type {
+ MAKE_PROPAGATION_UNCHANGED = 0, /* Don't change mount propagation (default). */
+ MAKE_PROPAGATION_UNBINDABLE = 1, /* Make unbindable. */
+ MAKE_PROPAGATION_PRIVATE = 2, /* Do not receive or send mount events. */
+ MAKE_PROPAGATION_DEPENDENT = 3, /* Only receive mount events. */
+ MAKE_PROPAGATION_SHARED = 4, /* Send and receive mount events. */
+};
+
+/* List of all mount_attr versions. */
+#define MOUNT_ATTR_SIZE_VER0 24 /* sizeof first published struct */
+#define MOUNT_ATTR_SIZE_LATEST MOUNT_ATTR_SIZE_VER0
+
#endif /* _UAPI_LINUX_MOUNT_H */
diff --git a/tools/include/uapi/asm-generic/unistd.h b/tools/include/uapi/asm-generic/unistd.h
index 2056318988f7..0517f36fe783 100644
--- a/tools/include/uapi/asm-generic/unistd.h
+++ b/tools/include/uapi/asm-generic/unistd.h
@@ -859,9 +859,11 @@ __SYSCALL(__NR_pidfd_getfd, sys_pidfd_getfd)
__SYSCALL(__NR_faccessat2, sys_faccessat2)
#define __NR_process_madvise 440
__SYSCALL(__NR_process_madvise, sys_process_madvise)
+#define __NR_mount_setattr 441
+__SYSCALL(__NR_mount_setattr, sys_mount_setattr)
#undef __NR_syscalls
-#define __NR_syscalls 441
+#define __NR_syscalls 442
/*
* 32 bit systems traditionally used different
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 05/38] tests: add mount_setattr() selftests
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (3 preceding siblings ...)
2020-11-28 21:34 ` [PATCH v3 04/38] fs: add mount_setattr() Christian Brauner
@ 2020-11-28 21:34 ` Christian Brauner
2020-11-28 21:34 ` [PATCH v3 06/38] fs: add id translation helpers Christian Brauner
` (31 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:34 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
Add a range of selftests for the new mount_setattr() syscall to verify
that it works as expected. This tests that:
- no invalid flags can be specified
- changing properties of a single mount works and leaves other mounts in
the mount tree unchanged
- changing a mount tre to read-only when one of the mounts has writers
fails and leaves the whole mount tree unchanged
- changing mount properties from multiple threads works
- changing atime settings works
- changing mount propagation works
- changing the mount options of a mount tree where the individual mounts
in the tree have different mount options only changes the flags that
were requested to change
- changing mount options from another mount namespace fails
- changing mount options from another user namespace fails
[==========] Running 9 tests from 2 test cases.
[ RUN ] mount_setattr.invalid_attributes
[ OK ] mount_setattr.invalid_attributes
[ RUN ] mount_setattr.basic
[ OK ] mount_setattr.basic
[ RUN ] mount_setattr.basic_recursive
[ OK ] mount_setattr.basic_recursive
[ RUN ] mount_setattr.mount_has_writers
[ OK ] mount_setattr.mount_has_writers
[ RUN ] mount_setattr.mixed_mount_options
[ OK ] mount_setattr.mixed_mount_options
[ RUN ] mount_setattr.time_changes
[ OK ] mount_setattr.time_changes
[ RUN ] mount_setattr.multi_threaded
[ OK ] mount_setattr.multi_threaded
[ RUN ] mount_setattr.wrong_user_namespace
[ OK ] mount_setattr.wrong_user_namespace
[ RUN ] mount_setattr.wrong_mount_namespace
[ OK ] mount_setattr.wrong_mount_namespace
[==========] 9 / 9 tests passed.
[ PASSED ]
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
tools/testing/selftests/Makefile | 1 +
.../selftests/mount_setattr/.gitignore | 1 +
.../testing/selftests/mount_setattr/Makefile | 7 +
tools/testing/selftests/mount_setattr/config | 1 +
.../mount_setattr/mount_setattr_test.c | 941 ++++++++++++++++++
5 files changed, 951 insertions(+)
create mode 100644 tools/testing/selftests/mount_setattr/.gitignore
create mode 100644 tools/testing/selftests/mount_setattr/Makefile
create mode 100644 tools/testing/selftests/mount_setattr/config
create mode 100644 tools/testing/selftests/mount_setattr/mount_setattr_test.c
diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index d9c283503159..87b7107dd9a6 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -34,6 +34,7 @@ TARGETS += memfd
TARGETS += memory-hotplug
TARGETS += mincore
TARGETS += mount
+TARGETS += mount_setattr
TARGETS += mqueue
TARGETS += net
TARGETS += net/forwarding
diff --git a/tools/testing/selftests/mount_setattr/.gitignore b/tools/testing/selftests/mount_setattr/.gitignore
new file mode 100644
index 000000000000..5f74d8488472
--- /dev/null
+++ b/tools/testing/selftests/mount_setattr/.gitignore
@@ -0,0 +1 @@
+mount_setattr_test
diff --git a/tools/testing/selftests/mount_setattr/Makefile b/tools/testing/selftests/mount_setattr/Makefile
new file mode 100644
index 000000000000..2250f7dcb81e
--- /dev/null
+++ b/tools/testing/selftests/mount_setattr/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+# Makefile for mount selftests.
+CFLAGS = -g -I../../../../usr/include/ -Wall -O2 -pthread
+
+TEST_GEN_FILES += mount_setattr_test
+
+include ../lib.mk
diff --git a/tools/testing/selftests/mount_setattr/config b/tools/testing/selftests/mount_setattr/config
new file mode 100644
index 000000000000..416bd53ce982
--- /dev/null
+++ b/tools/testing/selftests/mount_setattr/config
@@ -0,0 +1 @@
+CONFIG_USER_NS=y
diff --git a/tools/testing/selftests/mount_setattr/mount_setattr_test.c b/tools/testing/selftests/mount_setattr/mount_setattr_test.c
new file mode 100644
index 000000000000..d940356ab277
--- /dev/null
+++ b/tools/testing/selftests/mount_setattr/mount_setattr_test.c
@@ -0,0 +1,941 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <sched.h>
+#include <stdio.h>
+#include <errno.h>
+#include <pthread.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/mount.h>
+#include <sys/wait.h>
+#include <sys/vfs.h>
+#include <sys/statvfs.h>
+#include <sys/sysinfo.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <grp.h>
+#include <stdbool.h>
+#include <stdarg.h>
+
+#include "../kselftest_harness.h"
+
+#ifndef CLONE_NEWNS
+#define CLONE_NEWNS 0x00020000
+#endif
+
+#ifndef CLONE_NEWUSER
+#define CLONE_NEWUSER 0x10000000
+#endif
+
+#ifndef MS_REC
+#define MS_REC 16384
+#endif
+
+#ifndef MS_RELATIME
+#define MS_RELATIME (1 << 21)
+#endif
+
+#ifndef MS_STRICTATIME
+#define MS_STRICTATIME (1 << 24)
+#endif
+
+#ifndef MOUNT_ATTR_RDONLY
+#define MOUNT_ATTR_RDONLY 0x00000001
+#endif
+
+#ifndef MOUNT_ATTR_NOSUID
+#define MOUNT_ATTR_NOSUID 0x00000002
+#endif
+
+#ifndef MOUNT_ATTR_NOEXEC
+#define MOUNT_ATTR_NOEXEC 0x00000008
+#endif
+
+#ifndef MOUNT_ATTR_NODIRATIME
+#define MOUNT_ATTR_NODIRATIME 0x00000080
+#endif
+
+#ifndef MOUNT_ATTR__ATIME
+#define MOUNT_ATTR__ATIME 0x00000070
+#endif
+
+#ifndef MOUNT_ATTR_RELATIME
+#define MOUNT_ATTR_RELATIME 0x00000000
+#endif
+
+#ifndef MOUNT_ATTR_NOATIME
+#define MOUNT_ATTR_NOATIME 0x00000010
+#endif
+
+#ifndef MOUNT_ATTR_STRICTATIME
+#define MOUNT_ATTR_STRICTATIME 0x00000020
+#endif
+
+#ifndef AT_RECURSIVE
+#define AT_RECURSIVE 0x8000
+#endif
+
+#ifndef MAKE_PROPAGATION_SHARED
+#define MAKE_PROPAGATION_SHARED 4
+#endif
+
+#define DEFAULT_THREADS 4
+#define ptr_to_int(p) ((int)((intptr_t)(p)))
+#define int_to_ptr(u) ((void *)((intptr_t)(u)))
+
+#ifndef __NR_mount_setattr
+ #if defined __alpha__
+ #define __NR_mount_setattr 551
+ #elif defined _MIPS_SIM
+ #if _MIPS_SIM == _MIPS_SIM_ABI32 /* o32 */
+ #define __NR_mount_setattr 4441
+ #endif
+ #if _MIPS_SIM == _MIPS_SIM_NABI32 /* n32 */
+ #define __NR_mount_setattr 6441
+ #endif
+ #if _MIPS_SIM == _MIPS_SIM_ABI64 /* n64 */
+ #define __NR_mount_setattr 5441
+ #endif
+ #elif defined __ia64__
+ #define __NR_mount_setattr (441 + 1024)
+ #else
+ #define __NR_mount_setattr 441
+ #endif
+
+struct mount_attr {
+ __u64 attr_set;
+ __u64 attr_clr;
+ __u64 propagation;
+};
+#endif
+
+static inline int sys_mount_setattr(int dfd, const char *path, unsigned int flags,
+ struct mount_attr *attr, size_t size)
+{
+ return syscall(__NR_mount_setattr, dfd, path, flags, attr, size);
+}
+
+static ssize_t write_nointr(int fd, const void *buf, size_t count)
+{
+ ssize_t ret;
+
+ do {
+ ret = write(fd, buf, count);
+ } while (ret < 0 && errno == EINTR);
+
+ return ret;
+}
+
+static int write_file(const char *path, const void *buf, size_t count)
+{
+ int fd;
+ ssize_t ret;
+
+ fd = open(path, O_WRONLY | O_CLOEXEC | O_NOCTTY | O_NOFOLLOW);
+ if (fd < 0)
+ return -1;
+
+ ret = write_nointr(fd, buf, count);
+ close(fd);
+ if (ret < 0 || (size_t)ret != count)
+ return -1;
+
+ return 0;
+}
+
+static int create_and_enter_userns(void)
+{
+ uid_t uid;
+ gid_t gid;
+ char map[100];
+
+ uid = getuid();
+ gid = getgid();
+
+ if (unshare(CLONE_NEWUSER))
+ return -1;
+
+ if (write_file("/proc/self/setgroups", "deny", sizeof("deny") - 1) &&
+ errno != ENOENT)
+ return -1;
+
+ snprintf(map, sizeof(map), "0 %d 1", uid);
+ if (write_file("/proc/self/uid_map", map, strlen(map)))
+ return -1;
+
+
+ snprintf(map, sizeof(map), "0 %d 1", gid);
+ if (write_file("/proc/self/gid_map", map, strlen(map)))
+ return -1;
+
+ if (setgid(0))
+ return -1;
+
+ if (setuid(0))
+ return -1;
+
+ return 0;
+}
+
+static int prepare_unpriv_mountns(void)
+{
+ if (create_and_enter_userns())
+ return -1;
+
+ if (unshare(CLONE_NEWNS))
+ return -1;
+
+ if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0))
+ return -1;
+
+ return 0;
+}
+
+static int read_mnt_flags(const char *path)
+{
+ int ret;
+ struct statvfs stat;
+ unsigned int mnt_flags;
+
+ ret = statvfs(path, &stat);
+ if (ret != 0)
+ return -EINVAL;
+
+ if (stat.f_flag &
+ ~(ST_RDONLY | ST_NOSUID | ST_NODEV | ST_NOEXEC | ST_NOATIME |
+ ST_NODIRATIME | ST_RELATIME | ST_SYNCHRONOUS | ST_MANDLOCK))
+ return -EINVAL;
+
+ mnt_flags = 0;
+ if (stat.f_flag & ST_RDONLY)
+ mnt_flags |= MS_RDONLY;
+ if (stat.f_flag & ST_NOSUID)
+ mnt_flags |= MS_NOSUID;
+ if (stat.f_flag & ST_NODEV)
+ mnt_flags |= MS_NODEV;
+ if (stat.f_flag & ST_NOEXEC)
+ mnt_flags |= MS_NOEXEC;
+ if (stat.f_flag & ST_NOATIME)
+ mnt_flags |= MS_NOATIME;
+ if (stat.f_flag & ST_NODIRATIME)
+ mnt_flags |= MS_NODIRATIME;
+ if (stat.f_flag & ST_RELATIME)
+ mnt_flags |= MS_RELATIME;
+ if (stat.f_flag & ST_SYNCHRONOUS)
+ mnt_flags |= MS_SYNCHRONOUS;
+ if (stat.f_flag & ST_MANDLOCK)
+ mnt_flags |= ST_MANDLOCK;
+
+ return mnt_flags;
+}
+
+static char *get_field(char *src, int nfields)
+{
+ int i;
+ char *p = src;
+
+ for (i = 0; i < nfields; i++) {
+ while (*p && *p != ' ' && *p != '\t')
+ p++;
+
+ if (!*p)
+ break;
+
+ p++;
+ }
+
+ return p;
+}
+
+static void null_endofword(char *word)
+{
+ while (*word && *word != ' ' && *word != '\t')
+ word++;
+ *word = '\0';
+}
+
+static bool is_shared_mount(const char *path)
+{
+ size_t len = 0;
+ char *line = NULL;
+ FILE *f = NULL;
+
+ f = fopen("/proc/self/mountinfo", "re");
+ if (!f)
+ return false;
+
+ while (getline(&line, &len, f) != -1) {
+ char *opts, *target;
+
+ target = get_field(line, 4);
+ if (!target)
+ continue;
+
+ opts = get_field(target, 2);
+ if (!opts)
+ continue;
+
+ null_endofword(target);
+
+ if (strcmp(target, path) != 0)
+ continue;
+
+ null_endofword(opts);
+ if (strstr(opts, "shared:"))
+ return true;
+ }
+
+ free(line);
+ fclose(f);
+
+ return false;
+}
+
+static void *mount_setattr_thread(void *data)
+{
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOSUID,
+ .attr_clr = 0,
+ .propagation = MAKE_PROPAGATION_SHARED,
+ };
+
+ if (sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)))
+ pthread_exit(int_to_ptr(-1));
+
+ pthread_exit(int_to_ptr(0));
+}
+
+/* Attempt to de-conflict with the selftests tree. */
+#ifndef SKIP
+#define SKIP(s, ...) XFAIL(s, ##__VA_ARGS__)
+#endif
+
+static bool mount_setattr_supported(void)
+{
+ int ret;
+
+ ret = sys_mount_setattr(-EBADF, "", AT_EMPTY_PATH, NULL, 0);
+ if (ret < 0 && errno == ENOSYS)
+ return false;
+
+ return true;
+}
+
+FIXTURE(mount_setattr) {
+};
+
+FIXTURE_SETUP(mount_setattr)
+{
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ ASSERT_EQ(prepare_unpriv_mountns(), 0);
+
+ (void)umount2("/mnt", MNT_DETACH);
+ (void)umount2("/tmp", MNT_DETACH);
+
+ ASSERT_EQ(mount("testing", "/tmp", "tmpfs", MS_NOATIME | MS_NODEV,
+ "size=100000,mode=700"), 0);
+
+ ASSERT_EQ(mkdir("/tmp/B", 0777), 0);
+
+ ASSERT_EQ(mount("testing", "/tmp/B", "tmpfs", MS_NOATIME | MS_NODEV,
+ "size=100000,mode=700"), 0);
+
+ ASSERT_EQ(mkdir("/tmp/B/BB", 0777), 0);
+
+ ASSERT_EQ(mount("testing", "/tmp/B/BB", "tmpfs", MS_NOATIME | MS_NODEV,
+ "size=100000,mode=700"), 0);
+
+ ASSERT_EQ(mount("testing", "/mnt", "tmpfs", MS_NOATIME | MS_NODEV,
+ "size=100000,mode=700"), 0);
+
+ ASSERT_EQ(mkdir("/mnt/A", 0777), 0);
+
+ ASSERT_EQ(mount("testing", "/mnt/A", "tmpfs", MS_NOATIME | MS_NODEV,
+ "size=100000,mode=700"), 0);
+
+ ASSERT_EQ(mkdir("/mnt/A/AA", 0777), 0);
+
+ ASSERT_EQ(mount("/tmp", "/mnt/A/AA", NULL, MS_BIND | MS_REC, NULL), 0);
+
+ ASSERT_EQ(mkdir("/mnt/B", 0777), 0);
+
+ ASSERT_EQ(mount("testing", "/mnt/B", "ramfs",
+ MS_NOATIME | MS_NODEV | MS_NOSUID, 0), 0);
+
+ ASSERT_EQ(mkdir("/mnt/B/BB", 0777), 0);
+
+ ASSERT_EQ(mount("testing", "/tmp/B/BB", "devpts",
+ MS_RELATIME | MS_NOEXEC | MS_RDONLY, 0), 0);
+}
+
+FIXTURE_TEARDOWN(mount_setattr)
+{
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ (void)umount2("/mnt/A", MNT_DETACH);
+ (void)umount2("/tmp", MNT_DETACH);
+}
+
+TEST_F(mount_setattr, invalid_attributes)
+{
+ struct mount_attr invalid_attr = {
+ .attr_set = (1U << 31),
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr,
+ sizeof(invalid_attr)), 0);
+
+ invalid_attr.attr_set = 0;
+ invalid_attr.attr_clr = (1U << 31);
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr,
+ sizeof(invalid_attr)), 0);
+
+ invalid_attr.attr_clr = 0;
+ invalid_attr.propagation = (1U << 31);
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr,
+ sizeof(invalid_attr)), 0);
+
+ invalid_attr.attr_set = (1U << 31);
+ invalid_attr.attr_clr = (1U << 31);
+ invalid_attr.propagation = (1U << 31);
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr,
+ sizeof(invalid_attr)), 0);
+
+ ASSERT_NE(sys_mount_setattr(-1, "mnt/A", AT_RECURSIVE, &invalid_attr,
+ sizeof(invalid_attr)), 0);
+}
+
+TEST_F(mount_setattr, extensibility)
+{
+ unsigned int old_flags = 0, new_flags = 0, expected_flags = 0;
+ char *s = "dummy";
+ struct mount_attr invalid_attr = {};
+ struct mount_attr_large {
+ struct mount_attr attr1;
+ struct mount_attr attr2;
+ struct mount_attr attr3;
+ } large_attr = {};
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ old_flags = read_mnt_flags("/mnt/A");
+ ASSERT_GT(old_flags, 0);
+
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, NULL,
+ sizeof(invalid_attr)), 0);
+ ASSERT_EQ(errno, EFAULT);
+
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, (void *)s,
+ sizeof(invalid_attr)), 0);
+ ASSERT_EQ(errno, EINVAL);
+
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr, 0), 0);
+ ASSERT_EQ(errno, EINVAL);
+
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr,
+ sizeof(invalid_attr) / 2), 0);
+ ASSERT_EQ(errno, EINVAL);
+
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &invalid_attr,
+ sizeof(invalid_attr) / 2), 0);
+ ASSERT_EQ(errno, EINVAL);
+
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE,
+ (void *)&large_attr, sizeof(large_attr)), 0);
+
+ large_attr.attr3.attr_set = MOUNT_ATTR_RDONLY;
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE,
+ (void *)&large_attr, sizeof(large_attr)), 0);
+
+ large_attr.attr3.attr_set = 0;
+ large_attr.attr1.attr_set = MOUNT_ATTR_RDONLY;
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE,
+ (void *)&large_attr, sizeof(large_attr)), 0);
+
+ expected_flags = old_flags;
+ expected_flags |= MS_RDONLY;
+
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, expected_flags);
+}
+
+TEST_F(mount_setattr, basic)
+{
+ unsigned int old_flags = 0, new_flags = 0, expected_flags = 0;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME,
+ .attr_clr = MOUNT_ATTR__ATIME,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ old_flags = read_mnt_flags("/mnt/A");
+ ASSERT_GT(old_flags, 0);
+
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", 0, &attr, sizeof(attr)), 0);
+
+ expected_flags = old_flags;
+ expected_flags |= MS_RDONLY;
+ expected_flags |= MS_NOEXEC;
+ expected_flags &= ~MS_NOATIME;
+ expected_flags |= MS_RELATIME;
+
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, old_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, old_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, old_flags);
+}
+
+TEST_F(mount_setattr, basic_recursive)
+{
+ int fd;
+ unsigned int old_flags = 0, new_flags = 0, expected_flags = 0;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME,
+ .attr_clr = MOUNT_ATTR__ATIME,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ old_flags = read_mnt_flags("/mnt/A");
+ ASSERT_GT(old_flags, 0);
+
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ expected_flags = old_flags;
+ expected_flags |= MS_RDONLY;
+ expected_flags |= MS_NOEXEC;
+ expected_flags &= ~MS_NOATIME;
+ expected_flags |= MS_RELATIME;
+
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ memset(&attr, 0, sizeof(attr));
+ attr.attr_clr = MOUNT_ATTR_RDONLY;
+ attr.propagation = MAKE_PROPAGATION_SHARED;
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ expected_flags &= ~MS_RDONLY;
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A"), true);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A/AA"), true);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), true);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), true);
+
+ fd = open("/mnt/A/AA/B/b", O_RDWR | O_CLOEXEC | O_CREAT | O_EXCL, 0777);
+ ASSERT_GE(fd, 0);
+
+ /*
+ * We're holding a fd open for writing so this needs to fail somewhere
+ * in the middle and the mount options need to be unchanged.
+ */
+ attr.attr_set = MOUNT_ATTR_RDONLY;
+ ASSERT_LT(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A"), true);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A/AA"), true);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), true);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), true);
+
+ EXPECT_EQ(close(fd), 0);
+}
+
+TEST_F(mount_setattr, mount_has_writers)
+{
+ int fd, dfd;
+ unsigned int old_flags = 0, new_flags = 0;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOEXEC | MOUNT_ATTR_RELATIME,
+ .attr_clr = MOUNT_ATTR__ATIME,
+ .propagation = MAKE_PROPAGATION_SHARED,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ old_flags = read_mnt_flags("/mnt/A");
+ ASSERT_GT(old_flags, 0);
+
+ fd = open("/mnt/A/AA/B/b", O_RDWR | O_CLOEXEC | O_CREAT | O_EXCL, 0777);
+ ASSERT_GE(fd, 0);
+
+ /*
+ * We're holding a fd open to a mount somwhere in the middle so this
+ * needs to fail somewhere in the middle. After this the mount options
+ * need to be unchanged.
+ */
+ ASSERT_LT(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, old_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A"), false);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, old_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A/AA"), false);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, old_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), false);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, old_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), false);
+
+ dfd = open("/mnt/A/AA/B", O_DIRECTORY | O_CLOEXEC);
+ ASSERT_GE(dfd, 0);
+ EXPECT_EQ(fsync(dfd), 0);
+ EXPECT_EQ(close(dfd), 0);
+
+ EXPECT_EQ(fsync(fd), 0);
+ EXPECT_EQ(close(fd), 0);
+
+ /* All writers are gone so this should succeed. */
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+}
+
+TEST_F(mount_setattr, mixed_mount_options)
+{
+ unsigned int old_flags1 = 0, old_flags2 = 0, new_flags = 0, expected_flags = 0;
+ struct mount_attr attr = {
+ .attr_clr = MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOSUID | MOUNT_ATTR_NOEXEC | MOUNT_ATTR__ATIME,
+ .attr_set = MOUNT_ATTR_RELATIME,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ old_flags1 = read_mnt_flags("/mnt/B");
+ ASSERT_GT(old_flags1, 0);
+
+ old_flags2 = read_mnt_flags("/mnt/B/BB");
+ ASSERT_GT(old_flags2, 0);
+
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/B", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ expected_flags = old_flags2;
+ expected_flags &= ~(MS_RDONLY | MS_NOEXEC | MS_NOATIME | MS_NOSUID);
+ expected_flags |= MS_RELATIME;
+
+ new_flags = read_mnt_flags("/mnt/B");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ expected_flags = old_flags2;
+ expected_flags &= ~(MS_RDONLY | MS_NOEXEC | MS_NOATIME | MS_NOSUID);
+ expected_flags |= MS_RELATIME;
+
+ new_flags = read_mnt_flags("/mnt/B/BB");
+ ASSERT_EQ(new_flags, expected_flags);
+}
+
+TEST_F(mount_setattr, time_changes)
+{
+ unsigned int old_flags = 0, new_flags = 0, expected_flags = 0;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_NODIRATIME | MOUNT_ATTR_NOATIME,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ attr.attr_set = MOUNT_ATTR_STRICTATIME;
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ attr.attr_set = MOUNT_ATTR_STRICTATIME | MOUNT_ATTR_NOATIME;
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ attr.attr_set = MOUNT_ATTR_STRICTATIME | MOUNT_ATTR_NOATIME;
+ attr.attr_clr = MOUNT_ATTR__ATIME;
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ attr.attr_set = 0;
+ attr.attr_clr = MOUNT_ATTR_STRICTATIME;
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ attr.attr_clr = MOUNT_ATTR_NOATIME;
+ ASSERT_NE(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ old_flags = read_mnt_flags("/mnt/A");
+ ASSERT_GT(old_flags, 0);
+
+ attr.attr_set = MOUNT_ATTR_NODIRATIME | MOUNT_ATTR_NOATIME;
+ attr.attr_clr = MOUNT_ATTR__ATIME;
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ expected_flags = old_flags;
+ expected_flags |= MS_NOATIME;
+ expected_flags |= MS_NODIRATIME;
+
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ memset(&attr, 0, sizeof(attr));
+ attr.attr_set &= ~MOUNT_ATTR_NOATIME;
+ attr.attr_set |= MOUNT_ATTR_RELATIME;
+ attr.attr_clr |= MOUNT_ATTR__ATIME;
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ expected_flags &= ~MS_NOATIME;
+ expected_flags |= MS_RELATIME;
+
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ memset(&attr, 0, sizeof(attr));
+ attr.attr_set &= ~MOUNT_ATTR_RELATIME;
+ attr.attr_set |= MOUNT_ATTR_STRICTATIME;
+ attr.attr_clr |= MOUNT_ATTR__ATIME;
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ expected_flags &= ~MS_RELATIME;
+
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ memset(&attr, 0, sizeof(attr));
+ attr.attr_set &= ~MOUNT_ATTR_STRICTATIME;
+ attr.attr_set |= MOUNT_ATTR_NOATIME;
+ attr.attr_clr |= MOUNT_ATTR__ATIME;
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ expected_flags |= MS_NOATIME;
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ memset(&attr, 0, sizeof(attr));
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ memset(&attr, 0, sizeof(attr));
+ attr.attr_clr = MOUNT_ATTR_NODIRATIME;
+ ASSERT_EQ(sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr)), 0);
+
+ expected_flags &= ~MS_NODIRATIME;
+
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, expected_flags);
+}
+
+TEST_F(mount_setattr, multi_threaded)
+{
+ int i, j, nthreads, ret = 0;
+ unsigned int old_flags = 0, new_flags = 0, expected_flags = 0;
+ pthread_attr_t pattr;
+ pthread_t threads[DEFAULT_THREADS];
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ old_flags = read_mnt_flags("/mnt/A");
+ ASSERT_GT(old_flags, 0);
+
+ /* Try to change mount options from multiple threads. */
+ nthreads = get_nprocs_conf();
+ if (nthreads > DEFAULT_THREADS)
+ nthreads = DEFAULT_THREADS;
+
+ pthread_attr_init(&pattr);
+ for (i = 0; i < nthreads; i++)
+ ASSERT_EQ(pthread_create(&threads[i], &pattr, mount_setattr_thread, NULL), 0);
+
+ for (j = 0; j < i; j++) {
+ void *retptr = NULL;
+
+ EXPECT_EQ(pthread_join(threads[j], &retptr), 0);
+
+ ret += ptr_to_int(retptr);
+ EXPECT_EQ(ret, 0);
+ }
+ pthread_attr_destroy(&pattr);
+
+ ASSERT_EQ(ret, 0);
+
+ expected_flags = old_flags;
+ expected_flags |= MS_RDONLY;
+ expected_flags |= MS_NOSUID;
+ new_flags = read_mnt_flags("/mnt/A");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A"), true);
+
+ new_flags = read_mnt_flags("/mnt/A/AA");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A/AA"), true);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A/AA/B"), true);
+
+ new_flags = read_mnt_flags("/mnt/A/AA/B/BB");
+ ASSERT_EQ(new_flags, expected_flags);
+
+ ASSERT_EQ(is_shared_mount("/mnt/A/AA/B/BB"), true);
+}
+
+TEST_F(mount_setattr, wrong_user_namespace)
+{
+ int ret;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_RDONLY,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ EXPECT_EQ(create_and_enter_userns(), 0);
+ ret = sys_mount_setattr(-1, "/mnt/A", AT_RECURSIVE, &attr, sizeof(attr));
+ ASSERT_LT(ret, 0);
+ ASSERT_EQ(errno, EPERM);
+}
+
+TEST_F(mount_setattr, wrong_mount_namespace)
+{
+ int fd, ret;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_RDONLY,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ fd = open("/mnt/A", O_DIRECTORY | O_CLOEXEC);
+ ASSERT_GE(fd, 0);
+
+ ASSERT_EQ(unshare(CLONE_NEWNS), 0);
+
+ ret = sys_mount_setattr(fd, "", AT_EMPTY_PATH | AT_RECURSIVE, &attr, sizeof(attr));
+ ASSERT_LT(ret, 0);
+ ASSERT_EQ(errno, EINVAL);
+}
+
+TEST_HARNESS_MAIN
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 06/38] fs: add id translation helpers
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (4 preceding siblings ...)
2020-11-28 21:34 ` [PATCH v3 05/38] tests: add mount_setattr() selftests Christian Brauner
@ 2020-11-28 21:34 ` Christian Brauner
2020-12-01 10:49 ` Christoph Hellwig
2020-11-28 21:34 ` [PATCH v3 07/38] mount: attach mappings to mounts Christian Brauner
` (30 subsequent siblings)
36 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:34 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
Add simple helpers to make it easy to map kuids into and from idmapped
mounts. We provide simple wrappers that filesystems can use to
e.g. initialize inodes similar to i_{uid,gid}_read() and
i_{uid,gid}_write(). Accessing an inode through an idmapped mount will
require the inode to be mapped according to the mount's user namespace.
If the fsids are used to compare against inodes or to initialize inodes
they are required to be shifted from the mount's user namespace. Passing
the initial user namespace to these helpers makes them a nop and so any
non-idmapped paths will not be impacted.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Get rid of the ifdefs and the config option that hid idmapped mounts.
/* v3 */
unchanged
---
include/linux/fs.h | 43 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 43 insertions(+)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 8667d0cdc71e..f59b7f16f216 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -39,6 +39,7 @@
#include <linux/fs_types.h>
#include <linux/build_bug.h>
#include <linux/stddef.h>
+#include <linux/cred.h>
#include <asm/byteorder.h>
#include <uapi/linux/fs.h>
@@ -1574,6 +1575,48 @@ static inline void i_gid_write(struct inode *inode, gid_t gid)
inode->i_gid = make_kgid(inode->i_sb->s_user_ns, gid);
}
+static inline kuid_t kuid_into_mnt(struct user_namespace *to, kuid_t kuid)
+{
+ return make_kuid(to, __kuid_val(kuid));
+}
+
+static inline kgid_t kgid_into_mnt(struct user_namespace *to, kgid_t kgid)
+{
+ return make_kgid(to, __kgid_val(kgid));
+}
+
+static inline kuid_t i_uid_into_mnt(struct user_namespace *to,
+ const struct inode *inode)
+{
+ return kuid_into_mnt(to, inode->i_uid);
+}
+
+static inline kgid_t i_gid_into_mnt(struct user_namespace *to,
+ const struct inode *inode)
+{
+ return kgid_into_mnt(to, inode->i_gid);
+}
+
+static inline kuid_t kuid_from_mnt(struct user_namespace *to, kuid_t kuid)
+{
+ return KUIDT_INIT(from_kuid(to, kuid));
+}
+
+static inline kgid_t kgid_from_mnt(struct user_namespace *to, kgid_t kgid)
+{
+ return KGIDT_INIT(from_kgid(to, kgid));
+}
+
+static inline kuid_t fsuid_into_mnt(struct user_namespace *to)
+{
+ return kuid_from_mnt(to, current_fsuid());
+}
+
+static inline kgid_t fsgid_into_mnt(struct user_namespace *to)
+{
+ return kgid_from_mnt(to, current_fsgid());
+}
+
extern struct timespec64 current_time(struct inode *inode);
/*
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 07/38] mount: attach mappings to mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (5 preceding siblings ...)
2020-11-28 21:34 ` [PATCH v3 06/38] fs: add id translation helpers Christian Brauner
@ 2020-11-28 21:34 ` Christian Brauner
2020-12-01 10:50 ` Christoph Hellwig
2020-11-28 21:34 ` [PATCH v3 08/38] capability: handle idmapped mounts Christian Brauner
` (29 subsequent siblings)
36 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:34 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
In order to support per-mount idmappings vfsmounts will be marked with user
namespaces. The idmapping associated with that user namespace will be used to
map the ids of vfs objects when they are accessed through that mount. By
default all vfsmounts are marked with the initial user namespace. The initial
user namespace is used to indicate that a mount is not idmapped. All operations
behave as before.
Based on prior discussions we want to attach the whole user namespace and not
just a dedicated idmapping struct. This allows us to reuse all the helpers that
already exist for dealing with idmappings instead of introducing a whole new
range of helpers. In addition, if we decide in the future that we are confident
enough to enable unprivileged users to setup idmapped mounts we can allow
already idmapped mounts to be marked with another user namespace. The permission
checking would then take into account whether the caller is privileged in the
user namespace the mount is currently marked with. For now, we will enforce in
later patches that once a mount has been idmapped it can't be remapped. This
keeps permission checking and life-cycle management simple, especially since
users can always create a new mount with a different idmapping anyway.
The idea to attach user namespaces to vfsmounts has been floated around in
various forms at Linux Plumbers in ~2018 with the original idea tracing back to
a discussion during a conference in St. Petersburg between Christoph, Tycho, and
myself.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
patch introduced
- Christoph Hellwig <hch@lst.de>:
- Split internal implementation into separate patch and move syscall
implementation later.
/* v3 */
- David Howells <dhowells@redhat.com>:
- Remove MNT_IDMAPPED flag. We can simply check the pointer and use
smp_load_acquire() in later patches.
- Tycho Andersen <tycho@tycho.pizza>:
- Use READ_ONCE() in mnt_user_ns().
---
fs/namespace.c | 9 +++++++++
include/linux/fs.h | 1 +
include/linux/mount.h | 6 ++++++
3 files changed, 16 insertions(+)
diff --git a/fs/namespace.c b/fs/namespace.c
index f9ea31b7eb7f..a1fda548c3af 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -220,6 +220,7 @@ static struct mount *alloc_vfsmnt(const char *name)
INIT_HLIST_NODE(&mnt->mnt_mp_list);
INIT_LIST_HEAD(&mnt->mnt_umounting);
INIT_HLIST_HEAD(&mnt->mnt_stuck_children);
+ mnt->mnt.mnt_user_ns = &init_user_ns;
}
return mnt;
@@ -559,6 +560,11 @@ int sb_prepare_remount_readonly(struct super_block *sb)
static void free_vfsmnt(struct mount *mnt)
{
+ struct user_namespace *ns;
+
+ ns = mnt_user_ns(&mnt->mnt);
+ if (ns != &init_user_ns)
+ put_user_ns(ns);
kfree_const(mnt->mnt_devname);
#ifdef CONFIG_SMP
free_percpu(mnt->mnt_pcp);
@@ -1067,6 +1073,9 @@ static struct mount *clone_mnt(struct mount *old, struct dentry *root,
mnt->mnt.mnt_flags &= ~(MNT_WRITE_HOLD|MNT_MARKED|MNT_INTERNAL);
atomic_inc(&sb->s_active);
+ mnt->mnt.mnt_user_ns = mnt_user_ns(&old->mnt);
+ if (mnt->mnt.mnt_user_ns != &init_user_ns)
+ mnt->mnt.mnt_user_ns = get_user_ns(mnt->mnt.mnt_user_ns);
mnt->mnt.mnt_sb = sb;
mnt->mnt.mnt_root = dget(root);
mnt->mnt_mountpoint = mnt->mnt.mnt_root;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index f59b7f16f216..004686f49e32 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2276,6 +2276,7 @@ struct file_system_type {
#define FS_HAS_SUBTYPE 4
#define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
#define FS_DISALLOW_NOTIFY_PERM 16 /* Disable fanotify permission events */
+#define FS_ALLOW_IDMAP 32 /* FS has been updated to handle vfs idmappings. */
#define FS_THP_SUPPORT 8192 /* Remove once all fs converted */
#define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
int (*init_fs_context)(struct fs_context *);
diff --git a/include/linux/mount.h b/include/linux/mount.h
index aaf343b38671..d0d4a270acea 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -72,8 +72,14 @@ struct vfsmount {
struct dentry *mnt_root; /* root of the mounted tree */
struct super_block *mnt_sb; /* pointer to superblock */
int mnt_flags;
+ struct user_namespace *mnt_user_ns;
} __randomize_layout;
+static inline struct user_namespace *mnt_user_ns(const struct vfsmount *mnt)
+{
+ return READ_ONCE(mnt->mnt_user_ns);
+}
+
struct file; /* forward dec */
struct path;
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 08/38] capability: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (6 preceding siblings ...)
2020-11-28 21:34 ` [PATCH v3 07/38] mount: attach mappings to mounts Christian Brauner
@ 2020-11-28 21:34 ` Christian Brauner
2020-11-28 22:34 ` Serge E. Hallyn
2020-11-28 21:34 ` [PATCH v3 09/38] namei: add idmapped mount aware permission helpers Christian Brauner
` (28 subsequent siblings)
36 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:34 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
In order to determine whether a caller holds privilege over a given inode the
capability framework exposes the two helpers privileged_wrt_inode_uidgid() and
capable_wrt_inode_uidgid(). The former verifies that the inode has a mapping in
the caller's user namespace and the latter additionally verifies that the caller
has the requested capability in their current user namespace.
If the inode is accessed through an idmapped mount we simply need to map it
according to the mount's user namespace. Afterwards the checks are identical to
non-idmapped inodes. If the initial user namespace is passed all operations are
a nop so non-idmapped mounts will not see a change in behavior and will also not
see any performance impact.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Don't pollute the vfs with additional helpers simply extend the existing
helpers with an additional argument and switch all callers.
/* v3 */
unchanged
---
fs/attr.c | 8 ++++----
fs/exec.c | 2 +-
fs/inode.c | 2 +-
fs/namei.c | 13 ++++++++-----
fs/overlayfs/super.c | 2 +-
fs/posix_acl.c | 2 +-
fs/xfs/xfs_ioctl.c | 2 +-
include/linux/capability.h | 7 +++++--
kernel/capability.c | 14 +++++++++-----
security/commoncap.c | 5 +++--
10 files changed, 34 insertions(+), 23 deletions(-)
diff --git a/fs/attr.c b/fs/attr.c
index b4bbdbd4c8ca..d270f640a192 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -23,7 +23,7 @@ static bool chown_ok(const struct inode *inode, kuid_t uid)
if (uid_eq(current_fsuid(), inode->i_uid) &&
uid_eq(uid, inode->i_uid))
return true;
- if (capable_wrt_inode_uidgid(inode, CAP_CHOWN))
+ if (capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_CHOWN))
return true;
if (uid_eq(inode->i_uid, INVALID_UID) &&
ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN))
@@ -36,7 +36,7 @@ static bool chgrp_ok(const struct inode *inode, kgid_t gid)
if (uid_eq(current_fsuid(), inode->i_uid) &&
(in_group_p(gid) || gid_eq(gid, inode->i_gid)))
return true;
- if (capable_wrt_inode_uidgid(inode, CAP_CHOWN))
+ if (capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_CHOWN))
return true;
if (gid_eq(inode->i_gid, INVALID_GID) &&
ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN))
@@ -92,7 +92,7 @@ int setattr_prepare(struct dentry *dentry, struct iattr *attr)
/* Also check the setgid bit! */
if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
inode->i_gid) &&
- !capable_wrt_inode_uidgid(inode, CAP_FSETID))
+ !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID))
attr->ia_mode &= ~S_ISGID;
}
@@ -193,7 +193,7 @@ void setattr_copy(struct inode *inode, const struct iattr *attr)
umode_t mode = attr->ia_mode;
if (!in_group_p(inode->i_gid) &&
- !capable_wrt_inode_uidgid(inode, CAP_FSETID))
+ !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID))
mode &= ~S_ISGID;
inode->i_mode = mode;
}
diff --git a/fs/exec.c b/fs/exec.c
index 547a2390baf5..8e75d7a33514 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1398,7 +1398,7 @@ void would_dump(struct linux_binprm *bprm, struct file *file)
/* Ensure mm->user_ns contains the executable */
user_ns = old = bprm->mm->user_ns;
while ((user_ns != &init_user_ns) &&
- !privileged_wrt_inode_uidgid(user_ns, inode))
+ !privileged_wrt_inode_uidgid(user_ns, &init_user_ns, inode))
user_ns = user_ns->parent;
if (old != user_ns) {
diff --git a/fs/inode.c b/fs/inode.c
index 9d78c37b00b8..7a15372d9c2d 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -2147,7 +2147,7 @@ void inode_init_owner(struct inode *inode, const struct inode *dir,
mode |= S_ISGID;
else if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP) &&
!in_group_p(inode->i_gid) &&
- !capable_wrt_inode_uidgid(dir, CAP_FSETID))
+ !capable_wrt_inode_uidgid(&init_user_ns, dir, CAP_FSETID))
mode &= ~S_ISGID;
} else
inode->i_gid = current_fsgid();
diff --git a/fs/namei.c b/fs/namei.c
index d4a6dd772303..3f52730af6c5 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -357,10 +357,11 @@ int generic_permission(struct inode *inode, int mask)
if (S_ISDIR(inode->i_mode)) {
/* DACs are overridable for directories */
if (!(mask & MAY_WRITE))
- if (capable_wrt_inode_uidgid(inode,
+ if (capable_wrt_inode_uidgid(&init_user_ns, inode,
CAP_DAC_READ_SEARCH))
return 0;
- if (capable_wrt_inode_uidgid(inode, CAP_DAC_OVERRIDE))
+ if (capable_wrt_inode_uidgid(&init_user_ns, inode,
+ CAP_DAC_OVERRIDE))
return 0;
return -EACCES;
}
@@ -370,7 +371,8 @@ int generic_permission(struct inode *inode, int mask)
*/
mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
if (mask == MAY_READ)
- if (capable_wrt_inode_uidgid(inode, CAP_DAC_READ_SEARCH))
+ if (capable_wrt_inode_uidgid(&init_user_ns, inode,
+ CAP_DAC_READ_SEARCH))
return 0;
/*
* Read/write DACs are always overridable.
@@ -378,7 +380,8 @@ int generic_permission(struct inode *inode, int mask)
* at least one exec bit set.
*/
if (!(mask & MAY_EXEC) || (inode->i_mode & S_IXUGO))
- if (capable_wrt_inode_uidgid(inode, CAP_DAC_OVERRIDE))
+ if (capable_wrt_inode_uidgid(&init_user_ns, inode,
+ CAP_DAC_OVERRIDE))
return 0;
return -EACCES;
@@ -2657,7 +2660,7 @@ int __check_sticky(struct inode *dir, struct inode *inode)
return 0;
if (uid_eq(dir->i_uid, fsuid))
return 0;
- return !capable_wrt_inode_uidgid(inode, CAP_FOWNER);
+ return !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FOWNER);
}
EXPORT_SYMBOL(__check_sticky);
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 290983bcfbb3..196fe3e3f02b 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -972,7 +972,7 @@ ovl_posix_acl_xattr_set(const struct xattr_handler *handler,
if (unlikely(inode->i_mode & S_ISGID) &&
handler->flags == ACL_TYPE_ACCESS &&
!in_group_p(inode->i_gid) &&
- !capable_wrt_inode_uidgid(inode, CAP_FSETID)) {
+ !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID)) {
struct iattr iattr = { .ia_valid = ATTR_KILL_SGID };
err = ovl_setattr(dentry, &iattr);
diff --git a/fs/posix_acl.c b/fs/posix_acl.c
index 95882b3f5f62..4ca6d53c6f0a 100644
--- a/fs/posix_acl.c
+++ b/fs/posix_acl.c
@@ -656,7 +656,7 @@ int posix_acl_update_mode(struct inode *inode, umode_t *mode_p,
if (error == 0)
*acl = NULL;
if (!in_group_p(inode->i_gid) &&
- !capable_wrt_inode_uidgid(inode, CAP_FSETID))
+ !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID))
mode &= ~S_ISGID;
*mode_p = mode;
return 0;
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 3fbd98f61ea5..97bd29fc8c43 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1502,7 +1502,7 @@ xfs_ioctl_setattr(
*/
if ((VFS_I(ip)->i_mode & (S_ISUID|S_ISGID)) &&
- !capable_wrt_inode_uidgid(VFS_I(ip), CAP_FSETID))
+ !capable_wrt_inode_uidgid(&init_user_ns, VFS_I(ip), CAP_FSETID))
VFS_I(ip)->i_mode &= ~(S_ISUID|S_ISGID);
/* Change the ownerships and register project quota modifications */
diff --git a/include/linux/capability.h b/include/linux/capability.h
index 1e7fe311cabe..041e336f3369 100644
--- a/include/linux/capability.h
+++ b/include/linux/capability.h
@@ -247,8 +247,11 @@ static inline bool ns_capable_setid(struct user_namespace *ns, int cap)
return true;
}
#endif /* CONFIG_MULTIUSER */
-extern bool privileged_wrt_inode_uidgid(struct user_namespace *ns, const struct inode *inode);
-extern bool capable_wrt_inode_uidgid(const struct inode *inode, int cap);
+extern bool privileged_wrt_inode_uidgid(struct user_namespace *ns,
+ struct user_namespace *mnt_user_ns,
+ const struct inode *inode);
+extern bool capable_wrt_inode_uidgid(struct user_namespace *mnt_user_ns,
+ const struct inode *inode, int cap);
extern bool file_ns_capable(const struct file *file, struct user_namespace *ns, int cap);
extern bool ptracer_capable(struct task_struct *tsk, struct user_namespace *ns);
static inline bool perfmon_capable(void)
diff --git a/kernel/capability.c b/kernel/capability.c
index de7eac903a2a..28e3a599ff7a 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -484,10 +484,12 @@ EXPORT_SYMBOL(file_ns_capable);
*
* Return true if the inode uid and gid are within the namespace.
*/
-bool privileged_wrt_inode_uidgid(struct user_namespace *ns, const struct inode *inode)
+bool privileged_wrt_inode_uidgid(struct user_namespace *ns,
+ struct user_namespace *mnt_user_ns,
+ const struct inode *inode)
{
- return kuid_has_mapping(ns, inode->i_uid) &&
- kgid_has_mapping(ns, inode->i_gid);
+ return kuid_has_mapping(ns, i_uid_into_mnt(mnt_user_ns, inode)) &&
+ kgid_has_mapping(ns, i_gid_into_mnt(mnt_user_ns, inode));
}
/**
@@ -499,11 +501,13 @@ bool privileged_wrt_inode_uidgid(struct user_namespace *ns, const struct inode *
* its own user namespace and that the given inode's uid and gid are
* mapped into the current user namespace.
*/
-bool capable_wrt_inode_uidgid(const struct inode *inode, int cap)
+bool capable_wrt_inode_uidgid(struct user_namespace *mnt_user_ns,
+ const struct inode *inode, int cap)
{
struct user_namespace *ns = current_user_ns();
- return ns_capable(ns, cap) && privileged_wrt_inode_uidgid(ns, inode);
+ return ns_capable(ns, cap) &&
+ privileged_wrt_inode_uidgid(ns, mnt_user_ns, inode);
}
EXPORT_SYMBOL(capable_wrt_inode_uidgid);
diff --git a/security/commoncap.c b/security/commoncap.c
index 59bf3c1674c8..4cd2bdfd0a8b 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -489,7 +489,7 @@ int cap_convert_nscap(struct dentry *dentry, void **ivalue, size_t size)
return -EINVAL;
if (!validheader(size, cap))
return -EINVAL;
- if (!capable_wrt_inode_uidgid(inode, CAP_SETFCAP))
+ if (!capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_SETFCAP))
return -EPERM;
if (size == XATTR_CAPS_SZ_2)
if (ns_capable(inode->i_sb->s_user_ns, CAP_SETFCAP))
@@ -957,7 +957,8 @@ int cap_inode_removexattr(struct dentry *dentry, const char *name)
struct inode *inode = d_backing_inode(dentry);
if (!inode)
return -EINVAL;
- if (!capable_wrt_inode_uidgid(inode, CAP_SETFCAP))
+ if (!capable_wrt_inode_uidgid(&init_user_ns, inode,
+ CAP_SETFCAP))
return -EPERM;
return 0;
}
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 09/38] namei: add idmapped mount aware permission helpers
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (7 preceding siblings ...)
2020-11-28 21:34 ` [PATCH v3 08/38] capability: handle idmapped mounts Christian Brauner
@ 2020-11-28 21:34 ` Christian Brauner
2020-11-28 22:47 ` Serge E. Hallyn
2020-12-01 10:51 ` Christoph Hellwig
2020-11-28 21:34 ` [PATCH v3 10/38] inode: add idmapped mount aware init and " Christian Brauner
` (27 subsequent siblings)
36 siblings, 2 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:34 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
The two helpers inode_permission() and generic_permission() are used by the vfs
to perform basic permission checking by verifying that the caller is privileged
over an inode. In order to handle idmapped mounts we extend the two helpers with
an additional user namespace argument.
On idmapped mounts the two helpers will make sure to map the inode according to
the mount's user namespace and then peform identical permission checks to
inode_permission() and generic_permission(). If the initial user namespace is
passed nothing changes so non-idmapped mounts will see identical behavior as
before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Don't pollute the vfs with additional helpers simply extend the existing
helpers with an additional argument and switch all callers.
/* v3 */
unchanged
---
fs/attr.c | 3 +-
fs/btrfs/inode.c | 2 +-
fs/btrfs/ioctl.c | 10 ++---
fs/ceph/inode.c | 2 +-
fs/cifs/cifsfs.c | 2 +-
fs/configfs/symlink.c | 2 +-
fs/ecryptfs/inode.c | 2 +-
fs/exec.c | 2 +-
fs/fuse/dir.c | 4 +-
fs/gfs2/inode.c | 2 +-
fs/hostfs/hostfs_kern.c | 2 +-
fs/init.c | 9 ++--
fs/kernfs/inode.c | 2 +-
fs/libfs.c | 7 ++-
fs/namei.c | 68 +++++++++++++++++-------------
fs/nfs/dir.c | 2 +-
fs/nfsd/nfsfh.c | 2 +-
fs/nfsd/vfs.c | 4 +-
fs/nilfs2/inode.c | 2 +-
fs/notify/fanotify/fanotify_user.c | 2 +-
fs/notify/inotify/inotify_user.c | 2 +-
fs/ocfs2/file.c | 2 +-
fs/ocfs2/refcounttree.c | 4 +-
fs/open.c | 10 ++---
fs/orangefs/inode.c | 2 +-
fs/overlayfs/file.c | 2 +-
fs/overlayfs/inode.c | 4 +-
fs/overlayfs/util.c | 2 +-
fs/posix_acl.c | 17 +++++---
fs/proc/base.c | 4 +-
fs/proc/fd.c | 2 +-
fs/reiserfs/xattr.c | 2 +-
fs/remap_range.c | 2 +-
fs/udf/file.c | 2 +-
fs/verity/enable.c | 2 +-
fs/xattr.c | 2 +-
include/linux/fs.h | 4 +-
include/linux/posix_acl.h | 4 +-
ipc/mqueue.c | 2 +-
kernel/bpf/inode.c | 4 +-
kernel/cgroup/cgroup.c | 2 +-
kernel/sys.c | 2 +-
mm/madvise.c | 2 +-
mm/memcontrol.c | 2 +-
mm/mincore.c | 2 +-
net/unix/af_unix.c | 2 +-
46 files changed, 122 insertions(+), 96 deletions(-)
diff --git a/fs/attr.c b/fs/attr.c
index d270f640a192..c9e29e589cec 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -244,7 +244,8 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
return -EPERM;
if (!inode_owner_or_capable(inode)) {
- error = inode_permission(inode, MAY_WRITE);
+ error = inode_permission(&init_user_ns, inode,
+ MAY_WRITE);
if (error)
return error;
}
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index da58c58ef9aa..32e3bf88d4f7 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -9794,7 +9794,7 @@ static int btrfs_permission(struct inode *inode, int mask)
if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
return -EACCES;
}
- return generic_permission(inode, mask);
+ return generic_permission(&init_user_ns, inode, mask);
}
static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 69a384145dc6..74500c15bdc1 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -910,7 +910,7 @@ static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
BUG_ON(d_inode(victim->d_parent) != dir);
audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
- error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
+ error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
if (error)
return error;
if (IS_APPEND(dir))
@@ -939,7 +939,7 @@ static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
return -EEXIST;
if (IS_DEADDIR(dir))
return -ENOENT;
- return inode_permission(dir, MAY_WRITE | MAY_EXEC);
+ return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
}
/*
@@ -2487,7 +2487,7 @@ static int btrfs_search_path_in_tree_user(struct inode *inode,
ret = PTR_ERR(temp_inode);
goto out_put;
}
- ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC);
+ ret = inode_permission(&init_user_ns, temp_inode, MAY_READ | MAY_EXEC);
iput(temp_inode);
if (ret) {
ret = -EACCES;
@@ -3017,7 +3017,7 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
if (root == dest)
goto out_dput;
- err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
+ err = inode_permission(&init_user_ns, inode, MAY_WRITE | MAY_EXEC);
if (err)
goto out_dput;
}
@@ -3088,7 +3088,7 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
* running and allows defrag on files open in read-only mode.
*/
if (!capable(CAP_SYS_ADMIN) &&
- inode_permission(inode, MAY_WRITE)) {
+ inode_permission(&init_user_ns, inode, MAY_WRITE)) {
ret = -EPERM;
goto out;
}
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 526faf4778ce..abfe42df8a1a 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -2335,7 +2335,7 @@ int ceph_permission(struct inode *inode, int mask)
err = ceph_do_getattr(inode, CEPH_CAP_AUTH_SHARED, false);
if (!err)
- err = generic_permission(inode, mask);
+ err = generic_permission(&init_user_ns, inode, mask);
return err;
}
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 472cb7777e3e..f79dbc581eee 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -316,7 +316,7 @@ static int cifs_permission(struct inode *inode, int mask)
on the client (above and beyond ACL on servers) for
servers which do not support setting and viewing mode bits,
so allowing client to check permissions is useful */
- return generic_permission(inode, mask);
+ return generic_permission(&init_user_ns, inode, mask);
}
static struct kmem_cache *cifs_inode_cachep;
diff --git a/fs/configfs/symlink.c b/fs/configfs/symlink.c
index cb61467478ca..0b592c55f38e 100644
--- a/fs/configfs/symlink.c
+++ b/fs/configfs/symlink.c
@@ -197,7 +197,7 @@ int configfs_symlink(struct inode *dir, struct dentry *dentry, const char *symna
if (dentry->d_inode || d_unhashed(dentry))
ret = -EEXIST;
else
- ret = inode_permission(dir, MAY_WRITE | MAY_EXEC);
+ ret = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
if (!ret)
ret = type->ct_item_ops->allow_link(parent_item, target_item);
if (!ret) {
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index e23752d9a79f..9b1ae410983c 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -864,7 +864,7 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
static int
ecryptfs_permission(struct inode *inode, int mask)
{
- return inode_permission(ecryptfs_inode_to_lower(inode), mask);
+ return inode_permission(&init_user_ns, ecryptfs_inode_to_lower(inode), mask);
}
/**
diff --git a/fs/exec.c b/fs/exec.c
index 8e75d7a33514..b499a1a03934 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1391,7 +1391,7 @@ EXPORT_SYMBOL(begin_new_exec);
void would_dump(struct linux_binprm *bprm, struct file *file)
{
struct inode *inode = file_inode(file);
- if (inode_permission(inode, MAY_READ) < 0) {
+ if (inode_permission(&init_user_ns, inode, MAY_READ) < 0) {
struct user_namespace *old, *user_ns;
bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index ff7dbeb16f88..7ce7baed3f4f 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -1254,7 +1254,7 @@ static int fuse_permission(struct inode *inode, int mask)
}
if (fc->default_permissions) {
- err = generic_permission(inode, mask);
+ err = generic_permission(&init_user_ns, inode, mask);
/* If permission is denied, try to refresh file
attributes. This is also needed, because the root
@@ -1262,7 +1262,7 @@ static int fuse_permission(struct inode *inode, int mask)
if (err == -EACCES && !refreshed) {
err = fuse_perm_getattr(inode, mask);
if (!err)
- err = generic_permission(inode, mask);
+ err = generic_permission(&init_user_ns, inode, mask);
}
/* Note: the opposite of the above test does not
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 077ccb1b3ccc..8445588b58a6 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -1851,7 +1851,7 @@ int gfs2_permission(struct inode *inode, int mask)
if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
error = -EPERM;
else
- error = generic_permission(inode, mask);
+ error = generic_permission(&init_user_ns, inode, mask);
if (gfs2_holder_initialized(&i_gh))
gfs2_glock_dq_uninit(&i_gh);
diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index c070c0d8e3e9..36da0c31d053 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -779,7 +779,7 @@ static int hostfs_permission(struct inode *ino, int desired)
err = access_file(name, r, w, x);
__putname(name);
if (!err)
- err = generic_permission(ino, desired);
+ err = generic_permission(&init_user_ns, ino, desired);
return err;
}
diff --git a/fs/init.c b/fs/init.c
index e9c320a48cf1..2b4842f4802b 100644
--- a/fs/init.c
+++ b/fs/init.c
@@ -49,7 +49,8 @@ int __init init_chdir(const char *filename)
error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
if (error)
return error;
- error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+ error = inode_permission(&init_user_ns, path.dentry->d_inode,
+ MAY_EXEC | MAY_CHDIR);
if (!error)
set_fs_pwd(current->fs, &path);
path_put(&path);
@@ -64,7 +65,8 @@ int __init init_chroot(const char *filename)
error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
if (error)
return error;
- error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+ error = inode_permission(&init_user_ns, path.dentry->d_inode,
+ MAY_EXEC | MAY_CHDIR);
if (error)
goto dput_and_out;
error = -EPERM;
@@ -118,7 +120,8 @@ int __init init_eaccess(const char *filename)
error = kern_path(filename, LOOKUP_FOLLOW, &path);
if (error)
return error;
- error = inode_permission(d_inode(path.dentry), MAY_ACCESS);
+ error = inode_permission(&init_user_ns, d_inode(path.dentry),
+ MAY_ACCESS);
path_put(&path);
return error;
}
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index fc2469a20fed..ff5598cc1de0 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -285,7 +285,7 @@ int kernfs_iop_permission(struct inode *inode, int mask)
kernfs_refresh_inode(kn, inode);
mutex_unlock(&kernfs_mutex);
- return generic_permission(inode, mask);
+ return generic_permission(&init_user_ns, inode, mask);
}
int kernfs_xattr_get(struct kernfs_node *kn, const char *name,
diff --git a/fs/libfs.c b/fs/libfs.c
index fc34361c1489..23d0a00668fd 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -1316,9 +1316,14 @@ static ssize_t empty_dir_listxattr(struct dentry *dentry, char *list, size_t siz
return -EOPNOTSUPP;
}
+static int empty_dir_permission(struct inode *inode, int mask)
+{
+ return generic_permission(&init_user_ns, inode, mask);
+}
+
static const struct inode_operations empty_dir_inode_operations = {
.lookup = empty_dir_lookup,
- .permission = generic_permission,
+ .permission = empty_dir_permission,
.setattr = empty_dir_setattr,
.getattr = empty_dir_getattr,
.listxattr = empty_dir_listxattr,
diff --git a/fs/namei.c b/fs/namei.c
index 3f52730af6c5..38222f92efb6 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -259,7 +259,7 @@ void putname(struct filename *name)
__putname(name);
}
-static int check_acl(struct inode *inode, int mask)
+static int check_acl(struct user_namespace *user_ns, struct inode *inode, int mask)
{
#ifdef CONFIG_FS_POSIX_ACL
struct posix_acl *acl;
@@ -271,14 +271,14 @@ static int check_acl(struct inode *inode, int mask)
/* no ->get_acl() calls in RCU mode... */
if (is_uncached_acl(acl))
return -ECHILD;
- return posix_acl_permission(inode, acl, mask);
+ return posix_acl_permission(user_ns, inode, acl, mask);
}
acl = get_acl(inode, ACL_TYPE_ACCESS);
if (IS_ERR(acl))
return PTR_ERR(acl);
if (acl) {
- int error = posix_acl_permission(inode, acl, mask);
+ int error = posix_acl_permission(user_ns, inode, acl, mask);
posix_acl_release(acl);
return error;
}
@@ -293,12 +293,15 @@ static int check_acl(struct inode *inode, int mask)
* Note that the POSIX ACL check cares about the MAY_NOT_BLOCK bit,
* for RCU walking.
*/
-static int acl_permission_check(struct inode *inode, int mask)
+static int acl_permission_check(struct user_namespace *user_ns,
+ struct inode *inode, int mask)
{
unsigned int mode = inode->i_mode;
+ kuid_t i_uid;
/* Are we the owner? If so, ACL's don't matter */
- if (likely(uid_eq(current_fsuid(), inode->i_uid))) {
+ i_uid = i_uid_into_mnt(user_ns, inode);
+ if (likely(uid_eq(current_fsuid(), i_uid))) {
mask &= 7;
mode >>= 6;
return (mask & ~mode) ? -EACCES : 0;
@@ -306,7 +309,7 @@ static int acl_permission_check(struct inode *inode, int mask)
/* Do we have ACL's? */
if (IS_POSIXACL(inode) && (mode & S_IRWXG)) {
- int error = check_acl(inode, mask);
+ int error = check_acl(user_ns, inode, mask);
if (error != -EAGAIN)
return error;
}
@@ -320,7 +323,8 @@ static int acl_permission_check(struct inode *inode, int mask)
* about? Need to check group ownership if so.
*/
if (mask & (mode ^ (mode >> 3))) {
- if (in_group_p(inode->i_gid))
+ kgid_t kgid = i_gid_into_mnt(user_ns, inode);
+ if (in_group_p(kgid))
mode >>= 3;
}
@@ -343,25 +347,25 @@ static int acl_permission_check(struct inode *inode, int mask)
* request cannot be satisfied (eg. requires blocking or too much complexity).
* It would then be called again in ref-walk mode.
*/
-int generic_permission(struct inode *inode, int mask)
+int generic_permission(struct user_namespace *user_ns, struct inode *inode,
+ int mask)
{
int ret;
/*
* Do the basic permission checks.
*/
- ret = acl_permission_check(inode, mask);
+ ret = acl_permission_check(user_ns, inode, mask);
if (ret != -EACCES)
return ret;
if (S_ISDIR(inode->i_mode)) {
/* DACs are overridable for directories */
if (!(mask & MAY_WRITE))
- if (capable_wrt_inode_uidgid(&init_user_ns, inode,
+ if (capable_wrt_inode_uidgid(user_ns, inode,
CAP_DAC_READ_SEARCH))
return 0;
- if (capable_wrt_inode_uidgid(&init_user_ns, inode,
- CAP_DAC_OVERRIDE))
+ if (capable_wrt_inode_uidgid(user_ns, inode, CAP_DAC_OVERRIDE))
return 0;
return -EACCES;
}
@@ -371,7 +375,7 @@ int generic_permission(struct inode *inode, int mask)
*/
mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
if (mask == MAY_READ)
- if (capable_wrt_inode_uidgid(&init_user_ns, inode,
+ if (capable_wrt_inode_uidgid(user_ns, inode,
CAP_DAC_READ_SEARCH))
return 0;
/*
@@ -380,8 +384,7 @@ int generic_permission(struct inode *inode, int mask)
* at least one exec bit set.
*/
if (!(mask & MAY_EXEC) || (inode->i_mode & S_IXUGO))
- if (capable_wrt_inode_uidgid(&init_user_ns, inode,
- CAP_DAC_OVERRIDE))
+ if (capable_wrt_inode_uidgid(user_ns, inode, CAP_DAC_OVERRIDE))
return 0;
return -EACCES;
@@ -394,7 +397,8 @@ EXPORT_SYMBOL(generic_permission);
* flag in inode->i_opflags, that says "this has not special
* permission function, use the fast case".
*/
-static inline int do_inode_permission(struct inode *inode, int mask)
+static inline int do_inode_permission(struct user_namespace *user_ns,
+ struct inode *inode, int mask)
{
if (unlikely(!(inode->i_opflags & IOP_FASTPERM))) {
if (likely(inode->i_op->permission))
@@ -405,7 +409,7 @@ static inline int do_inode_permission(struct inode *inode, int mask)
inode->i_opflags |= IOP_FASTPERM;
spin_unlock(&inode->i_lock);
}
- return generic_permission(inode, mask);
+ return generic_permission(user_ns, inode, mask);
}
/**
@@ -430,6 +434,7 @@ static int sb_permission(struct super_block *sb, struct inode *inode, int mask)
/**
* inode_permission - Check for access rights to a given inode
+ * @userns: The user namespace the inode is seen from
* @inode: Inode to check permission on
* @mask: Right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
*
@@ -439,7 +444,8 @@ static int sb_permission(struct super_block *sb, struct inode *inode, int mask)
*
* When checking for MAY_APPEND, MAY_WRITE must also be set in @mask.
*/
-int inode_permission(struct inode *inode, int mask)
+int inode_permission(struct user_namespace *user_ns,
+ struct inode *inode, int mask)
{
int retval;
@@ -463,7 +469,7 @@ int inode_permission(struct inode *inode, int mask)
return -EACCES;
}
- retval = do_inode_permission(inode, mask);
+ retval = do_inode_permission(user_ns, inode, mask);
if (retval)
return retval;
@@ -1009,7 +1015,7 @@ static bool safe_hardlink_source(struct inode *inode)
return false;
/* Hardlinking to unreadable or unwritable sources is dangerous. */
- if (inode_permission(inode, MAY_READ | MAY_WRITE))
+ if (inode_permission(&init_user_ns, inode, MAY_READ | MAY_WRITE))
return false;
return true;
@@ -1569,13 +1575,14 @@ static struct dentry *lookup_slow(const struct qstr *name,
static inline int may_lookup(struct nameidata *nd)
{
if (nd->flags & LOOKUP_RCU) {
- int err = inode_permission(nd->inode, MAY_EXEC|MAY_NOT_BLOCK);
+ int err = inode_permission(&init_user_ns, nd->inode,
+ MAY_EXEC | MAY_NOT_BLOCK);
if (err != -ECHILD)
return err;
if (unlazy_walk(nd))
return -ECHILD;
}
- return inode_permission(nd->inode, MAY_EXEC);
+ return inode_permission(&init_user_ns, nd->inode, MAY_EXEC);
}
static int reserve_stack(struct nameidata *nd, struct path *link, unsigned seq)
@@ -2507,7 +2514,7 @@ static int lookup_one_len_common(const char *name, struct dentry *base,
return err;
}
- return inode_permission(base->d_inode, MAY_EXEC);
+ return inode_permission(&init_user_ns, base->d_inode, MAY_EXEC);
}
/**
@@ -2701,7 +2708,7 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
- error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
+ error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
if (error)
return error;
if (IS_APPEND(dir))
@@ -2745,7 +2752,7 @@ static inline int may_create(struct inode *dir, struct dentry *child)
if (!kuid_has_mapping(s_user_ns, current_fsuid()) ||
!kgid_has_mapping(s_user_ns, current_fsgid()))
return -EOVERFLOW;
- return inode_permission(dir, MAY_WRITE | MAY_EXEC);
+ return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
}
/*
@@ -2875,7 +2882,7 @@ static int may_open(const struct path *path, int acc_mode, int flag)
break;
}
- error = inode_permission(inode, MAY_OPEN | acc_mode);
+ error = inode_permission(&init_user_ns, inode, MAY_OPEN | acc_mode);
if (error)
return error;
@@ -2937,7 +2944,8 @@ static int may_o_create(const struct path *dir, struct dentry *dentry, umode_t m
!kgid_has_mapping(s_user_ns, current_fsgid()))
return -EOVERFLOW;
- error = inode_permission(dir->dentry->d_inode, MAY_WRITE | MAY_EXEC);
+ error = inode_permission(&init_user_ns, dir->dentry->d_inode,
+ MAY_WRITE | MAY_EXEC);
if (error)
return error;
@@ -3274,7 +3282,7 @@ struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag)
int error;
/* we want directory to be writable */
- error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
+ error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
if (error)
goto out_err;
error = -EOPNOTSUPP;
@@ -4265,12 +4273,12 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
*/
if (new_dir != old_dir) {
if (is_dir) {
- error = inode_permission(source, MAY_WRITE);
+ error = inode_permission(&init_user_ns, source, MAY_WRITE);
if (error)
return error;
}
if ((flags & RENAME_EXCHANGE) && new_is_dir) {
- error = inode_permission(target, MAY_WRITE);
+ error = inode_permission(&init_user_ns, target, MAY_WRITE);
if (error)
return error;
}
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 4e011adaf967..170ecc575519 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -2788,7 +2788,7 @@ int nfs_permission(struct inode *inode, int mask)
res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
if (res == 0)
- res = generic_permission(inode, mask);
+ res = generic_permission(&init_user_ns, inode, mask);
goto out;
}
EXPORT_SYMBOL_GPL(nfs_permission);
diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c
index c81dbbad8792..380f0f74740c 100644
--- a/fs/nfsd/nfsfh.c
+++ b/fs/nfsd/nfsfh.c
@@ -40,7 +40,7 @@ static int nfsd_acceptable(void *expv, struct dentry *dentry)
/* make sure parents give x permission to user */
int err;
parent = dget_parent(tdentry);
- err = inode_permission(d_inode(parent), MAY_EXEC);
+ err = inode_permission(&init_user_ns, d_inode(parent), MAY_EXEC);
if (err < 0) {
dput(parent);
break;
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 1ecaceebee13..3cad79c3b441 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -2380,13 +2380,13 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
return 0;
/* This assumes NFSD_MAY_{READ,WRITE,EXEC} == MAY_{READ,WRITE,EXEC} */
- err = inode_permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC));
+ err = inode_permission(&init_user_ns, inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC));
/* Allow read access to binaries even when mode 111 */
if (err == -EACCES && S_ISREG(inode->i_mode) &&
(acc == (NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE) ||
acc == (NFSD_MAY_READ | NFSD_MAY_READ_IF_EXEC)))
- err = inode_permission(inode, MAY_EXEC);
+ err = inode_permission(&init_user_ns, inode, MAY_EXEC);
return err? nfserrno(err) : 0;
}
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 745d371d6fea..b6517220cad5 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -851,7 +851,7 @@ int nilfs_permission(struct inode *inode, int mask)
root->cno != NILFS_CPTREE_CURRENT_CNO)
return -EROFS; /* snapshot is not writable */
- return generic_permission(inode, mask);
+ return generic_permission(&init_user_ns, inode, mask);
}
int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh)
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 3e01d8f2ab90..de4d01bb1d8d 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -702,7 +702,7 @@ static int fanotify_find_path(int dfd, const char __user *filename,
}
/* you can only watch an inode if you have read permissions on it */
- ret = inode_permission(path->dentry->d_inode, MAY_READ);
+ ret = inode_permission(&init_user_ns, path->dentry->d_inode, MAY_READ);
if (ret) {
path_put(path);
goto out;
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 186722ba3894..e995fd4e4e53 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -343,7 +343,7 @@ static int inotify_find_inode(const char __user *dirname, struct path *path,
if (error)
return error;
/* you can only watch an inode if you have read permissions on it */
- error = inode_permission(path->dentry->d_inode, MAY_READ);
+ error = inode_permission(&init_user_ns, path->dentry->d_inode, MAY_READ);
if (error) {
path_put(path);
return error;
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 85979e2214b3..0c75619adf54 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1355,7 +1355,7 @@ int ocfs2_permission(struct inode *inode, int mask)
dump_stack();
}
- ret = generic_permission(inode, mask);
+ ret = generic_permission(&init_user_ns, inode, mask);
ocfs2_inode_unlock_tracker(inode, 0, &oh, had_lock);
out:
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index 3b397fa9c9e8..c26937824be1 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -4346,7 +4346,7 @@ static inline int ocfs2_may_create(struct inode *dir, struct dentry *child)
return -EEXIST;
if (IS_DEADDIR(dir))
return -ENOENT;
- return inode_permission(dir, MAY_WRITE | MAY_EXEC);
+ return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
}
/**
@@ -4400,7 +4400,7 @@ static int ocfs2_vfs_reflink(struct dentry *old_dentry, struct inode *dir,
* file.
*/
if (!preserve) {
- error = inode_permission(inode, MAY_READ);
+ error = inode_permission(&init_user_ns, inode, MAY_READ);
if (error)
return error;
}
diff --git a/fs/open.c b/fs/open.c
index 9af548fb841b..b0e8430e29f3 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -83,7 +83,7 @@ long vfs_truncate(const struct path *path, loff_t length)
if (error)
goto out;
- error = inode_permission(inode, MAY_WRITE);
+ error = inode_permission(&init_user_ns, inode, MAY_WRITE);
if (error)
goto mnt_drop_write_and_out;
@@ -436,7 +436,7 @@ static long do_faccessat(int dfd, const char __user *filename, int mode, int fla
goto out_path_release;
}
- res = inode_permission(inode, mode | MAY_ACCESS);
+ res = inode_permission(&init_user_ns, inode, mode | MAY_ACCESS);
/* SuS v2 requires we report a read only fs too */
if (res || !(mode & S_IWOTH) || special_file(inode->i_mode))
goto out_path_release;
@@ -492,7 +492,7 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename)
if (error)
goto out;
- error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+ error = inode_permission(&init_user_ns, path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
if (error)
goto dput_and_out;
@@ -521,7 +521,7 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd)
if (!d_can_lookup(f.file->f_path.dentry))
goto out_putf;
- error = inode_permission(file_inode(f.file), MAY_EXEC | MAY_CHDIR);
+ error = inode_permission(&init_user_ns, file_inode(f.file), MAY_EXEC | MAY_CHDIR);
if (!error)
set_fs_pwd(current->fs, &f.file->f_path);
out_putf:
@@ -540,7 +540,7 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename)
if (error)
goto out;
- error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+ error = inode_permission(&init_user_ns, path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
if (error)
goto dput_and_out;
diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c
index 48f0547d4850..4c790cc8042d 100644
--- a/fs/orangefs/inode.c
+++ b/fs/orangefs/inode.c
@@ -933,7 +933,7 @@ int orangefs_permission(struct inode *inode, int mask)
if (ret < 0)
return ret;
- return generic_permission(inode, mask);
+ return generic_permission(&init_user_ns, inode, mask);
}
int orangefs_update_time(struct inode *inode, struct timespec64 *time, int flags)
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index efccb7c1f9bc..f966b5108358 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -50,7 +50,7 @@ static struct file *ovl_open_realfile(const struct file *file,
acc_mode |= MAY_APPEND;
old_cred = ovl_override_creds(inode->i_sb);
- err = inode_permission(realinode, MAY_OPEN | acc_mode);
+ err = inode_permission(&init_user_ns, realinode, MAY_OPEN | acc_mode);
if (err) {
realfile = ERR_PTR(err);
} else if (!inode_owner_or_capable(realinode)) {
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index b584dca845ba..c8e3c17ca131 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -294,7 +294,7 @@ int ovl_permission(struct inode *inode, int mask)
* Check overlay inode with the creds of task and underlying inode
* with creds of mounter
*/
- err = generic_permission(inode, mask);
+ err = generic_permission(&init_user_ns, inode, mask);
if (err)
return err;
@@ -305,7 +305,7 @@ int ovl_permission(struct inode *inode, int mask)
/* Make sure mounter can read file for copy up later */
mask |= MAY_READ;
}
- err = inode_permission(realinode, mask);
+ err = inode_permission(&init_user_ns, realinode, mask);
revert_creds(old_cred);
return err;
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index 23f475627d07..ff67da201303 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -476,7 +476,7 @@ struct file *ovl_path_open(struct path *path, int flags)
BUG();
}
- err = inode_permission(inode, acc_mode | MAY_OPEN);
+ err = inode_permission(&init_user_ns, inode, acc_mode | MAY_OPEN);
if (err)
return ERR_PTR(err);
diff --git a/fs/posix_acl.c b/fs/posix_acl.c
index 4ca6d53c6f0a..5b6296cc89c4 100644
--- a/fs/posix_acl.c
+++ b/fs/posix_acl.c
@@ -345,10 +345,13 @@ EXPORT_SYMBOL(posix_acl_from_mode);
* by the acl. Returns -E... otherwise.
*/
int
-posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want)
+posix_acl_permission(struct user_namespace *user_ns, struct inode *inode,
+ const struct posix_acl *acl, int want)
{
const struct posix_acl_entry *pa, *pe, *mask_obj;
int found = 0;
+ kuid_t uid;
+ kgid_t gid;
want &= MAY_READ | MAY_WRITE | MAY_EXEC;
@@ -356,22 +359,26 @@ posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want)
switch(pa->e_tag) {
case ACL_USER_OBJ:
/* (May have been checked already) */
- if (uid_eq(inode->i_uid, current_fsuid()))
+ uid = i_uid_into_mnt(user_ns, inode);
+ if (uid_eq(uid, current_fsuid()))
goto check_perm;
break;
case ACL_USER:
- if (uid_eq(pa->e_uid, current_fsuid()))
+ uid = kuid_into_mnt(user_ns, pa->e_uid);
+ if (uid_eq(uid, current_fsuid()))
goto mask;
break;
case ACL_GROUP_OBJ:
- if (in_group_p(inode->i_gid)) {
+ gid = i_gid_into_mnt(user_ns, inode);
+ if (in_group_p(gid)) {
found = 1;
if ((pa->e_perm & want) == want)
goto mask;
}
break;
case ACL_GROUP:
- if (in_group_p(pa->e_gid)) {
+ gid = kgid_into_mnt(user_ns, pa->e_gid);
+ if (in_group_p(gid)) {
found = 1;
if ((pa->e_perm & want) == want)
goto mask;
diff --git a/fs/proc/base.c b/fs/proc/base.c
index b362523a9829..ff7259f820c8 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -751,7 +751,7 @@ static int proc_pid_permission(struct inode *inode, int mask)
return -EPERM;
}
- return generic_permission(inode, mask);
+ return generic_permission(&init_user_ns, inode, mask);
}
@@ -3489,7 +3489,7 @@ static int proc_tid_comm_permission(struct inode *inode, int mask)
return 0;
}
- return generic_permission(inode, mask);
+ return generic_permission(&init_user_ns, inode, mask);
}
static const struct inode_operations proc_tid_comm_inode_operations = {
diff --git a/fs/proc/fd.c b/fs/proc/fd.c
index 81882a13212d..ad692a39381d 100644
--- a/fs/proc/fd.c
+++ b/fs/proc/fd.c
@@ -299,7 +299,7 @@ int proc_fd_permission(struct inode *inode, int mask)
struct task_struct *p;
int rv;
- rv = generic_permission(inode, mask);
+ rv = generic_permission(&init_user_ns, inode, mask);
if (rv == 0)
return rv;
diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c
index fe63a7c3e0da..ec440d1957a1 100644
--- a/fs/reiserfs/xattr.c
+++ b/fs/reiserfs/xattr.c
@@ -957,7 +957,7 @@ int reiserfs_permission(struct inode *inode, int mask)
if (IS_PRIVATE(inode))
return 0;
- return generic_permission(inode, mask);
+ return generic_permission(&init_user_ns, inode, mask);
}
static int xattr_hide_revalidate(struct dentry *dentry, unsigned int flags)
diff --git a/fs/remap_range.c b/fs/remap_range.c
index e6099beefa97..9e5b27641756 100644
--- a/fs/remap_range.c
+++ b/fs/remap_range.c
@@ -438,7 +438,7 @@ static bool allow_file_dedupe(struct file *file)
return true;
if (uid_eq(current_fsuid(), file_inode(file)->i_uid))
return true;
- if (!inode_permission(file_inode(file), MAY_WRITE))
+ if (!inode_permission(&init_user_ns, file_inode(file), MAY_WRITE))
return true;
return false;
}
diff --git a/fs/udf/file.c b/fs/udf/file.c
index ad8eefad27d7..928283925d68 100644
--- a/fs/udf/file.c
+++ b/fs/udf/file.c
@@ -183,7 +183,7 @@ long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
long old_block, new_block;
int result;
- if (inode_permission(inode, MAY_READ) != 0) {
+ if (inode_permission(&init_user_ns, inode, MAY_READ) != 0) {
udf_debug("no permission to access inode %lu\n", inode->i_ino);
return -EPERM;
}
diff --git a/fs/verity/enable.c b/fs/verity/enable.c
index 5ab3bbec8108..7449ef0050f4 100644
--- a/fs/verity/enable.c
+++ b/fs/verity/enable.c
@@ -369,7 +369,7 @@ int fsverity_ioctl_enable(struct file *filp, const void __user *uarg)
* has verity enabled, and to stabilize the data being hashed.
*/
- err = inode_permission(inode, MAY_WRITE);
+ err = inode_permission(&init_user_ns, inode, MAY_WRITE);
if (err)
return err;
diff --git a/fs/xattr.c b/fs/xattr.c
index cd7a563e8bcd..61a9947f62f4 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -131,7 +131,7 @@ xattr_permission(struct inode *inode, const char *name, int mask)
return -EPERM;
}
- return inode_permission(inode, mask);
+ return inode_permission(&init_user_ns, inode, mask);
}
/*
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 004686f49e32..fa1137a232d1 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2803,8 +2803,8 @@ static inline int bmap(struct inode *inode, sector_t *block)
#endif
extern int notify_change(struct dentry *, struct iattr *, struct inode **);
-extern int inode_permission(struct inode *, int);
-extern int generic_permission(struct inode *, int);
+extern int inode_permission(struct user_namespace *, struct inode *, int);
+extern int generic_permission(struct user_namespace *, struct inode *, int);
extern int __check_sticky(struct inode *dir, struct inode *inode);
static inline bool execute_ok(struct inode *inode)
diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h
index 90797f1b421d..8276baefed13 100644
--- a/include/linux/posix_acl.h
+++ b/include/linux/posix_acl.h
@@ -15,6 +15,8 @@
#include <linux/refcount.h>
#include <uapi/linux/posix_acl.h>
+struct user_namespace;
+
struct posix_acl_entry {
short e_tag;
unsigned short e_perm;
@@ -62,7 +64,7 @@ posix_acl_release(struct posix_acl *acl)
extern void posix_acl_init(struct posix_acl *, int);
extern struct posix_acl *posix_acl_alloc(int, gfp_t);
extern int posix_acl_valid(struct user_namespace *, const struct posix_acl *);
-extern int posix_acl_permission(struct inode *, const struct posix_acl *, int);
+extern int posix_acl_permission(struct user_namespace *, struct inode *, const struct posix_acl *, int);
extern struct posix_acl *posix_acl_from_mode(umode_t, gfp_t);
extern int posix_acl_equiv_mode(const struct posix_acl *, umode_t *);
extern int __posix_acl_create(struct posix_acl **, gfp_t, umode_t *);
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index beff0cfcd1e8..693f01fe1216 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -873,7 +873,7 @@ static int prepare_open(struct dentry *dentry, int oflag, int ro,
if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY))
return -EINVAL;
acc = oflag2acc[oflag & O_ACCMODE];
- return inode_permission(d_inode(dentry), acc);
+ return inode_permission(&init_user_ns, d_inode(dentry), acc);
}
static int do_mq_open(const char __user *u_name, int oflag, umode_t mode,
diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
index dd4b7fd60ee7..f1c393e5d47d 100644
--- a/kernel/bpf/inode.c
+++ b/kernel/bpf/inode.c
@@ -507,7 +507,7 @@ static void *bpf_obj_do_get(const char __user *pathname,
return ERR_PTR(ret);
inode = d_backing_inode(path.dentry);
- ret = inode_permission(inode, ACC_MODE(flags));
+ ret = inode_permission(&init_user_ns, inode, ACC_MODE(flags));
if (ret)
goto out;
@@ -558,7 +558,7 @@ int bpf_obj_get_user(const char __user *pathname, int flags)
static struct bpf_prog *__get_prog_inode(struct inode *inode, enum bpf_prog_type type)
{
struct bpf_prog *prog;
- int ret = inode_permission(inode, MAY_READ);
+ int ret = inode_permission(&init_user_ns, inode, MAY_READ);
if (ret)
return ERR_PTR(ret);
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index e41c21819ba0..b13aab5a9715 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -4673,7 +4673,7 @@ static int cgroup_may_write(const struct cgroup *cgrp, struct super_block *sb)
if (!inode)
return -ENOMEM;
- ret = inode_permission(inode, MAY_WRITE);
+ ret = inode_permission(&init_user_ns, inode, MAY_WRITE);
iput(inode);
return ret;
}
diff --git a/kernel/sys.c b/kernel/sys.c
index a730c03ee607..469a659c8e84 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1847,7 +1847,7 @@ static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
if (!S_ISREG(inode->i_mode) || path_noexec(&exe.file->f_path))
goto exit;
- err = inode_permission(inode, MAY_EXEC);
+ err = inode_permission(&init_user_ns, inode, MAY_EXEC);
if (err)
goto exit;
diff --git a/mm/madvise.c b/mm/madvise.c
index 416a56b8e757..8afabc363b6b 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -540,7 +540,7 @@ static inline bool can_do_pageout(struct vm_area_struct *vma)
* opens a side channel.
*/
return inode_owner_or_capable(file_inode(vma->vm_file)) ||
- inode_permission(file_inode(vma->vm_file), MAY_WRITE) == 0;
+ inode_permission(&init_user_ns, file_inode(vma->vm_file), MAY_WRITE) == 0;
}
static long madvise_pageout(struct vm_area_struct *vma,
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 3dcbf24d2227..aed83b3ad11c 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -4906,7 +4906,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
/* the process need read permission on control file */
/* AV: shouldn't we check that it's been opened for read instead? */
- ret = inode_permission(file_inode(cfile.file), MAY_READ);
+ ret = inode_permission(&init_user_ns, file_inode(cfile.file), MAY_READ);
if (ret < 0)
goto out_put_cfile;
diff --git a/mm/mincore.c b/mm/mincore.c
index 02db1a834021..d5a58e61eac6 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -167,7 +167,7 @@ static inline bool can_do_mincore(struct vm_area_struct *vma)
* mappings, which opens a side channel.
*/
return inode_owner_or_capable(file_inode(vma->vm_file)) ||
- inode_permission(file_inode(vma->vm_file), MAY_WRITE) == 0;
+ inode_permission(&init_user_ns, file_inode(vma->vm_file), MAY_WRITE) == 0;
}
static const struct mm_walk_ops mincore_walk_ops = {
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 41c3303c3357..f568526d4a02 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -936,7 +936,7 @@ static struct sock *unix_find_other(struct net *net,
if (err)
goto fail;
inode = d_backing_inode(path.dentry);
- err = inode_permission(inode, MAY_WRITE);
+ err = inode_permission(&init_user_ns, inode, MAY_WRITE);
if (err)
goto put_fail;
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 10/38] inode: add idmapped mount aware init and permission helpers
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (8 preceding siblings ...)
2020-11-28 21:34 ` [PATCH v3 09/38] namei: add idmapped mount aware permission helpers Christian Brauner
@ 2020-11-28 21:34 ` Christian Brauner
2020-12-01 10:51 ` Christoph Hellwig
2020-11-28 21:35 ` [PATCH v3 11/38] attr: handle idmapped mounts Christian Brauner
` (26 subsequent siblings)
36 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:34 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
The inode_owner_or_capable() helper determines whether the caller is the owner
of the inode or is capable with respect to that inode. Allow it to handle
idmapped mounts. If the inode is accessed through an idmapped mount we first
need to map it according to the mount's user namespace. Afterwards the checks
are identical to non-idmapped mounts. If the initial user namespace is passed
nothing changes so non-idmapped mounts will see identical behavior as before.
Similarly, we allow the inode_init_owner() helper to handle idmapped
mounts. It initializes a new inode on idmapped mounts by mapping the fsuid
and fsgid of the caller from the mount's user namespace. If the initial user
namespace is passed nothing changes so non-idmapped mounts will see identical
behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Don't pollute the vfs with additional helpers simply extend the existing
helpers with an additional argument and switch all callers.
/* v3 */
unchanged
---
fs/9p/acl.c | 2 +-
fs/9p/vfs_inode.c | 2 +-
fs/attr.c | 6 +++---
fs/bfs/dir.c | 2 +-
fs/btrfs/inode.c | 2 +-
fs/btrfs/ioctl.c | 10 +++++-----
fs/btrfs/tests/btrfs-tests.c | 2 +-
fs/crypto/policy.c | 2 +-
fs/efivarfs/file.c | 2 +-
fs/ext2/ialloc.c | 2 +-
fs/ext2/ioctl.c | 6 +++---
fs/ext4/ialloc.c | 2 +-
fs/ext4/ioctl.c | 14 +++++++-------
fs/f2fs/file.c | 14 +++++++-------
fs/f2fs/namei.c | 2 +-
fs/f2fs/xattr.c | 2 +-
fs/fcntl.c | 2 +-
fs/gfs2/file.c | 2 +-
fs/hfsplus/inode.c | 2 +-
fs/hfsplus/ioctl.c | 2 +-
fs/hugetlbfs/inode.c | 2 +-
fs/inode.c | 23 ++++++++++++++---------
fs/jfs/ioctl.c | 2 +-
fs/jfs/jfs_inode.c | 2 +-
fs/minix/bitmap.c | 2 +-
fs/namei.c | 4 ++--
fs/nilfs2/inode.c | 2 +-
fs/nilfs2/ioctl.c | 2 +-
fs/ocfs2/dlmfs/dlmfs.c | 4 ++--
fs/ocfs2/ioctl.c | 2 +-
fs/ocfs2/namei.c | 2 +-
fs/omfs/inode.c | 2 +-
fs/overlayfs/dir.c | 2 +-
fs/overlayfs/file.c | 4 ++--
fs/overlayfs/super.c | 2 +-
fs/overlayfs/util.c | 2 +-
fs/posix_acl.c | 2 +-
fs/ramfs/inode.c | 2 +-
fs/reiserfs/ioctl.c | 4 ++--
fs/reiserfs/namei.c | 2 +-
fs/sysv/ialloc.c | 2 +-
fs/ubifs/dir.c | 2 +-
fs/ubifs/ioctl.c | 2 +-
fs/udf/ialloc.c | 2 +-
fs/ufs/ialloc.c | 2 +-
fs/xattr.c | 2 +-
fs/xfs/xfs_ioctl.c | 2 +-
fs/zonefs/super.c | 2 +-
include/linux/fs.h | 7 ++++---
kernel/bpf/inode.c | 2 +-
mm/madvise.c | 2 +-
mm/mincore.c | 2 +-
mm/shmem.c | 2 +-
security/selinux/hooks.c | 4 ++--
54 files changed, 95 insertions(+), 89 deletions(-)
diff --git a/fs/9p/acl.c b/fs/9p/acl.c
index 6261719f6f2a..d77b28e8d57a 100644
--- a/fs/9p/acl.c
+++ b/fs/9p/acl.c
@@ -258,7 +258,7 @@ static int v9fs_xattr_set_acl(const struct xattr_handler *handler,
if (S_ISLNK(inode->i_mode))
return -EOPNOTSUPP;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
if (value) {
/* update the cached acl value */
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index ae0c38ad1fcb..f058e89df30f 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -251,7 +251,7 @@ int v9fs_init_inode(struct v9fs_session_info *v9ses,
{
int err = 0;
- inode_init_owner(inode, NULL, mode);
+ inode_init_owner(inode, &init_user_ns, NULL, mode);
inode->i_blocks = 0;
inode->i_rdev = rdev;
inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
diff --git a/fs/attr.c b/fs/attr.c
index c9e29e589cec..00ae0b000146 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -87,7 +87,7 @@ int setattr_prepare(struct dentry *dentry, struct iattr *attr)
/* Make sure a caller can chmod. */
if (ia_valid & ATTR_MODE) {
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
/* Also check the setgid bit! */
if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
@@ -98,7 +98,7 @@ int setattr_prepare(struct dentry *dentry, struct iattr *attr)
/* Check for setting the inode time. */
if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) {
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
}
@@ -243,7 +243,7 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
if (IS_IMMUTABLE(inode))
return -EPERM;
- if (!inode_owner_or_capable(inode)) {
+ if (!inode_owner_or_capable(&init_user_ns, inode)) {
error = inode_permission(&init_user_ns, inode,
MAY_WRITE);
if (error)
diff --git a/fs/bfs/dir.c b/fs/bfs/dir.c
index d8dfe3a0cb39..c5ae76a87be5 100644
--- a/fs/bfs/dir.c
+++ b/fs/bfs/dir.c
@@ -96,7 +96,7 @@ static int bfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
}
set_bit(ino, info->si_imap);
info->si_freei--;
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
inode->i_blocks = 0;
inode->i_op = &bfs_file_inops;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 32e3bf88d4f7..ed1a5bf5f068 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -6015,7 +6015,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
if (ret != 0)
goto fail_unlock;
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
inode_set_bytes(inode, 0);
inode->i_mtime = current_time(inode);
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 74500c15bdc1..f5d3ebca4c5f 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -205,7 +205,7 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
const char *comp = NULL;
u32 binode_flags;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
if (btrfs_root_readonly(root))
@@ -417,7 +417,7 @@ static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg)
unsigned old_i_flags;
int ret = 0;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
if (btrfs_root_readonly(root))
@@ -1811,7 +1811,7 @@ static noinline int __btrfs_ioctl_snap_create(struct file *file,
btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
"Snapshot src from another FS");
ret = -EXDEV;
- } else if (!inode_owner_or_capable(src_inode)) {
+ } else if (!inode_owner_or_capable(&init_user_ns, src_inode)) {
/*
* Subvolume creation is not restricted, but snapshots
* are limited to own subvolumes only
@@ -1931,7 +1931,7 @@ static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
u64 flags;
int ret = 0;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
ret = mnt_want_write_file(file);
@@ -4401,7 +4401,7 @@ static long _btrfs_ioctl_set_received_subvol(struct file *file,
int ret = 0;
int received_uuid_changed;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
ret = mnt_want_write_file(file);
diff --git a/fs/btrfs/tests/btrfs-tests.c b/fs/btrfs/tests/btrfs-tests.c
index 999c14e5d0bd..ac8e604d44e3 100644
--- a/fs/btrfs/tests/btrfs-tests.c
+++ b/fs/btrfs/tests/btrfs-tests.c
@@ -56,7 +56,7 @@ struct inode *btrfs_new_test_inode(void)
inode = new_inode(test_mnt->mnt_sb);
if (inode)
- inode_init_owner(inode, NULL, S_IFREG);
+ inode_init_owner(inode, &init_user_ns, NULL, S_IFREG);
return inode;
}
diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c
index 4441d9944b9e..6ddd9f0d8b36 100644
--- a/fs/crypto/policy.c
+++ b/fs/crypto/policy.c
@@ -462,7 +462,7 @@ int fscrypt_ioctl_set_policy(struct file *filp, const void __user *arg)
return -EFAULT;
policy.version = version;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
ret = mnt_want_write_file(filp);
diff --git a/fs/efivarfs/file.c b/fs/efivarfs/file.c
index feaa5e182b7b..e6bc0302643b 100644
--- a/fs/efivarfs/file.c
+++ b/fs/efivarfs/file.c
@@ -137,7 +137,7 @@ efivarfs_ioc_setxflags(struct file *file, void __user *arg)
unsigned int oldflags = efivarfs_getflags(inode);
int error;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
if (copy_from_user(&flags, arg, sizeof(flags)))
diff --git a/fs/ext2/ialloc.c b/fs/ext2/ialloc.c
index 432c3febea6d..5081f2dd8a20 100644
--- a/fs/ext2/ialloc.c
+++ b/fs/ext2/ialloc.c
@@ -551,7 +551,7 @@ struct inode *ext2_new_inode(struct inode *dir, umode_t mode,
inode->i_uid = current_fsuid();
inode->i_gid = dir->i_gid;
} else
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
inode->i_ino = ino;
inode->i_blocks = 0;
diff --git a/fs/ext2/ioctl.c b/fs/ext2/ioctl.c
index 32a8d10b579d..b399cbb7022d 100644
--- a/fs/ext2/ioctl.c
+++ b/fs/ext2/ioctl.c
@@ -39,7 +39,7 @@ long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
if (ret)
return ret;
- if (!inode_owner_or_capable(inode)) {
+ if (!inode_owner_or_capable(&init_user_ns, inode)) {
ret = -EACCES;
goto setflags_out;
}
@@ -84,7 +84,7 @@ long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
case EXT2_IOC_SETVERSION: {
__u32 generation;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
ret = mnt_want_write_file(filp);
if (ret)
@@ -117,7 +117,7 @@ long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
return -ENOTTY;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
if (get_user(rsv_window_size, (int __user *)arg))
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index b215c564bc31..d91f69282311 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -972,7 +972,7 @@ struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir,
inode->i_uid = current_fsuid();
inode->i_gid = dir->i_gid;
} else
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
if (ext4_has_feature_project(sb) &&
ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT))
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index f0381876a7e5..e35aba820254 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -139,7 +139,7 @@ static long swap_inode_boot_loader(struct super_block *sb,
}
if (IS_RDONLY(inode) || IS_APPEND(inode) || IS_IMMUTABLE(inode) ||
- !inode_owner_or_capable(inode) || !capable(CAP_SYS_ADMIN)) {
+ !inode_owner_or_capable(&init_user_ns, inode) || !capable(CAP_SYS_ADMIN)) {
err = -EPERM;
goto journal_err_out;
}
@@ -829,7 +829,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
case FS_IOC_SETFLAGS: {
int err;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
if (get_user(flags, (int __user *) arg))
@@ -871,7 +871,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
__u32 generation;
int err;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
if (ext4_has_metadata_csum(inode->i_sb)) {
@@ -1010,7 +1010,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
case EXT4_IOC_MIGRATE:
{
int err;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
err = mnt_want_write_file(filp);
@@ -1032,7 +1032,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
case EXT4_IOC_ALLOC_DA_BLKS:
{
int err;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
err = mnt_want_write_file(filp);
@@ -1214,7 +1214,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
case EXT4_IOC_CLEAR_ES_CACHE:
{
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
ext4_clear_inode_es(inode);
return 0;
@@ -1260,7 +1260,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return -EFAULT;
/* Make sure caller has proper permission */
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
if (fa.fsx_xflags & ~EXT4_SUPPORTED_FS_XFLAGS)
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index ee861c6d9ff0..333442e96cc4 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -1955,7 +1955,7 @@ static int f2fs_ioc_setflags(struct file *filp, unsigned long arg)
u32 iflags;
int ret;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
if (get_user(fsflags, (int __user *)arg))
@@ -2002,7 +2002,7 @@ static int f2fs_ioc_start_atomic_write(struct file *filp)
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
int ret;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
if (!S_ISREG(inode->i_mode))
@@ -2069,7 +2069,7 @@ static int f2fs_ioc_commit_atomic_write(struct file *filp)
struct inode *inode = file_inode(filp);
int ret;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
ret = mnt_want_write_file(filp);
@@ -2111,7 +2111,7 @@ static int f2fs_ioc_start_volatile_write(struct file *filp)
struct inode *inode = file_inode(filp);
int ret;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
if (!S_ISREG(inode->i_mode))
@@ -2146,7 +2146,7 @@ static int f2fs_ioc_release_volatile_write(struct file *filp)
struct inode *inode = file_inode(filp);
int ret;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
ret = mnt_want_write_file(filp);
@@ -2175,7 +2175,7 @@ static int f2fs_ioc_abort_volatile_write(struct file *filp)
struct inode *inode = file_inode(filp);
int ret;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
ret = mnt_want_write_file(filp);
@@ -3153,7 +3153,7 @@ static int f2fs_ioc_fssetxattr(struct file *filp, unsigned long arg)
return -EFAULT;
/* Make sure caller has proper permission */
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
if (fa.fsx_xflags & ~F2FS_SUPPORTED_XFLAGS)
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 8fa37d1434de..66b522e61e50 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -46,7 +46,7 @@ static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
nid_free = true;
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
inode->i_ino = ino;
inode->i_blocks = 0;
diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c
index 65afcc3cc68a..d772bf13a814 100644
--- a/fs/f2fs/xattr.c
+++ b/fs/f2fs/xattr.c
@@ -114,7 +114,7 @@ static int f2fs_xattr_advise_set(const struct xattr_handler *handler,
unsigned char old_advise = F2FS_I(inode)->i_advise;
unsigned char new_advise;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
if (value == NULL)
return -EINVAL;
diff --git a/fs/fcntl.c b/fs/fcntl.c
index 19ac5baad50f..df091d435603 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -46,7 +46,7 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
/* O_NOATIME can only be set by the owner or superuser */
if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME))
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
/* required for strict SunOS emulation */
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index b39b339feddc..1d994bdfffaa 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c
@@ -238,7 +238,7 @@ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask,
goto out;
error = -EACCES;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
goto out;
error = 0;
diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c
index e3da9e96b835..02d51cbcff04 100644
--- a/fs/hfsplus/inode.c
+++ b/fs/hfsplus/inode.c
@@ -376,7 +376,7 @@ struct inode *hfsplus_new_inode(struct super_block *sb, struct inode *dir,
return NULL;
inode->i_ino = sbi->next_cnid++;
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
set_nlink(inode, 1);
inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
diff --git a/fs/hfsplus/ioctl.c b/fs/hfsplus/ioctl.c
index ce15b9496b77..3edb1926d127 100644
--- a/fs/hfsplus/ioctl.c
+++ b/fs/hfsplus/ioctl.c
@@ -91,7 +91,7 @@ static int hfsplus_ioctl_setflags(struct file *file, int __user *user_flags)
if (err)
goto out;
- if (!inode_owner_or_capable(inode)) {
+ if (!inode_owner_or_capable(&init_user_ns, inode)) {
err = -EACCES;
goto out_drop_write;
}
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index b5c109703daa..fed6ddfc3f3a 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -836,7 +836,7 @@ static struct inode *hugetlbfs_get_inode(struct super_block *sb,
struct hugetlbfs_inode_info *info = HUGETLBFS_I(inode);
inode->i_ino = get_next_ino();
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
lockdep_set_class(&inode->i_mapping->i_mmap_rwsem,
&hugetlbfs_i_mmap_rwsem_key);
inode->i_mapping->a_ops = &hugetlbfs_aops;
diff --git a/fs/inode.c b/fs/inode.c
index 7a15372d9c2d..d6dfa876c58d 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -2132,13 +2132,14 @@ EXPORT_SYMBOL(init_special_inode);
/**
* inode_init_owner - Init uid,gid,mode for new inode according to posix standards
* @inode: New inode
+ * @user_ns: User namespace the inode is accessed from
* @dir: Directory inode
* @mode: mode of the new inode
*/
-void inode_init_owner(struct inode *inode, const struct inode *dir,
- umode_t mode)
+void inode_init_owner(struct inode *inode, struct user_namespace *user_ns,
+ const struct inode *dir, umode_t mode)
{
- inode->i_uid = current_fsuid();
+ inode->i_uid = fsuid_into_mnt(user_ns);
if (dir && dir->i_mode & S_ISGID) {
inode->i_gid = dir->i_gid;
@@ -2146,31 +2147,35 @@ void inode_init_owner(struct inode *inode, const struct inode *dir,
if (S_ISDIR(mode))
mode |= S_ISGID;
else if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP) &&
- !in_group_p(inode->i_gid) &&
- !capable_wrt_inode_uidgid(&init_user_ns, dir, CAP_FSETID))
+ !in_group_p(i_gid_into_mnt(user_ns, inode)) &&
+ !capable_wrt_inode_uidgid(user_ns, dir, CAP_FSETID))
mode &= ~S_ISGID;
} else
- inode->i_gid = current_fsgid();
+ inode->i_gid = fsgid_into_mnt(user_ns);
inode->i_mode = mode;
}
EXPORT_SYMBOL(inode_init_owner);
/**
* inode_owner_or_capable - check current task permissions to inode
+ * @user_ns: User namespace the inode is accessed from
* @inode: inode being checked
*
* Return true if current either has CAP_FOWNER in a namespace with the
* inode owner uid mapped, or owns the file.
*/
-bool inode_owner_or_capable(const struct inode *inode)
+bool inode_owner_or_capable(struct user_namespace *user_ns,
+ const struct inode *inode)
{
+ kuid_t i_uid;
struct user_namespace *ns;
- if (uid_eq(current_fsuid(), inode->i_uid))
+ i_uid = i_uid_into_mnt(user_ns, inode);
+ if (uid_eq(current_fsuid(), i_uid))
return true;
ns = current_user_ns();
- if (kuid_has_mapping(ns, inode->i_uid) && ns_capable(ns, CAP_FOWNER))
+ if (kuid_has_mapping(ns, i_uid) && ns_capable(ns, CAP_FOWNER))
return true;
return false;
}
diff --git a/fs/jfs/ioctl.c b/fs/jfs/ioctl.c
index 10ee0ecca1a8..2581d4db58ff 100644
--- a/fs/jfs/ioctl.c
+++ b/fs/jfs/ioctl.c
@@ -76,7 +76,7 @@ long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
if (err)
return err;
- if (!inode_owner_or_capable(inode)) {
+ if (!inode_owner_or_capable(&init_user_ns, inode)) {
err = -EACCES;
goto setflags_out;
}
diff --git a/fs/jfs/jfs_inode.c b/fs/jfs/jfs_inode.c
index 4cef170630db..282a785bbf29 100644
--- a/fs/jfs/jfs_inode.c
+++ b/fs/jfs/jfs_inode.c
@@ -64,7 +64,7 @@ struct inode *ialloc(struct inode *parent, umode_t mode)
goto fail_put;
}
- inode_init_owner(inode, parent, mode);
+ inode_init_owner(inode, &init_user_ns, parent, mode);
/*
* New inodes need to save sane values on disk when
* uid & gid mount options are used
diff --git a/fs/minix/bitmap.c b/fs/minix/bitmap.c
index f4e5e5181a14..d99a78c83fbc 100644
--- a/fs/minix/bitmap.c
+++ b/fs/minix/bitmap.c
@@ -252,7 +252,7 @@ struct inode *minix_new_inode(const struct inode *dir, umode_t mode, int *error)
iput(inode);
return NULL;
}
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
inode->i_ino = j;
inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
inode->i_blocks = 0;
diff --git a/fs/namei.c b/fs/namei.c
index 38222f92efb6..35952c28ee29 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1047,7 +1047,7 @@ int may_linkat(struct path *link)
/* Source inode owner (or CAP_FOWNER) can hardlink all they like,
* otherwise, it must be a safe source.
*/
- if (safe_hardlink_source(inode) || inode_owner_or_capable(inode))
+ if (safe_hardlink_source(inode) || inode_owner_or_capable(&init_user_ns, inode))
return 0;
audit_log_path_denied(AUDIT_ANOM_LINK, "linkat");
@@ -2897,7 +2897,7 @@ static int may_open(const struct path *path, int acc_mode, int flag)
}
/* O_NOATIME can only be set by the owner or superuser */
- if (flag & O_NOATIME && !inode_owner_or_capable(inode))
+ if (flag & O_NOATIME && !inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
return 0;
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index b6517220cad5..d286c3bf7d43 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -348,7 +348,7 @@ struct inode *nilfs_new_inode(struct inode *dir, umode_t mode)
/* reference count of i_bh inherits from nilfs_mdt_read_block() */
atomic64_inc(&root->inodes_count);
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
inode->i_ino = ino;
inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index 07d26f61f22a..b053b40315bf 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -132,7 +132,7 @@ static int nilfs_ioctl_setflags(struct inode *inode, struct file *filp,
unsigned int flags, oldflags;
int ret;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
if (get_user(flags, (int __user *)argp))
diff --git a/fs/ocfs2/dlmfs/dlmfs.c b/fs/ocfs2/dlmfs/dlmfs.c
index 583820ec63e2..64491af88239 100644
--- a/fs/ocfs2/dlmfs/dlmfs.c
+++ b/fs/ocfs2/dlmfs/dlmfs.c
@@ -329,7 +329,7 @@ static struct inode *dlmfs_get_root_inode(struct super_block *sb)
if (inode) {
inode->i_ino = get_next_ino();
- inode_init_owner(inode, NULL, mode);
+ inode_init_owner(inode, &init_user_ns, NULL, mode);
inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
inc_nlink(inode);
@@ -352,7 +352,7 @@ static struct inode *dlmfs_get_inode(struct inode *parent,
return NULL;
inode->i_ino = get_next_ino();
- inode_init_owner(inode, parent, mode);
+ inode_init_owner(inode, &init_user_ns, parent, mode);
inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
ip = DLMFS_I(inode);
diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c
index 89984172fc4a..50c9b30ee9f6 100644
--- a/fs/ocfs2/ioctl.c
+++ b/fs/ocfs2/ioctl.c
@@ -96,7 +96,7 @@ static int ocfs2_set_inode_attr(struct inode *inode, unsigned flags,
}
status = -EACCES;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
goto bail_unlock;
if (!S_ISDIR(inode->i_mode))
diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index c46bf7f581a1..51a80acbb97e 100644
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -198,7 +198,7 @@ static struct inode *ocfs2_get_init_inode(struct inode *dir, umode_t mode)
* callers. */
if (S_ISDIR(mode))
set_nlink(inode, 2);
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
status = dquot_initialize(inode);
if (status)
return ERR_PTR(status);
diff --git a/fs/omfs/inode.c b/fs/omfs/inode.c
index ce93ccca8639..eed9e1273104 100644
--- a/fs/omfs/inode.c
+++ b/fs/omfs/inode.c
@@ -48,7 +48,7 @@ struct inode *omfs_new_inode(struct inode *dir, umode_t mode)
goto fail;
inode->i_ino = new_block;
- inode_init_owner(inode, NULL, mode);
+ inode_init_owner(inode, &init_user_ns, NULL, mode);
inode->i_mapping->a_ops = &omfs_aops;
inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 28a075b5f5b2..80b2fab73df7 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -636,7 +636,7 @@ static int ovl_create_object(struct dentry *dentry, int mode, dev_t rdev,
inode->i_state |= I_CREATING;
spin_unlock(&inode->i_lock);
- inode_init_owner(inode, dentry->d_parent->d_inode, mode);
+ inode_init_owner(inode, &init_user_ns, dentry->d_parent->d_inode, mode);
attr.mode = inode->i_mode;
err = ovl_create_or_link(dentry, inode, &attr, false);
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index f966b5108358..d58b49a1ea3b 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -53,7 +53,7 @@ static struct file *ovl_open_realfile(const struct file *file,
err = inode_permission(&init_user_ns, realinode, MAY_OPEN | acc_mode);
if (err) {
realfile = ERR_PTR(err);
- } else if (!inode_owner_or_capable(realinode)) {
+ } else if (!inode_owner_or_capable(&init_user_ns, realinode)) {
realfile = ERR_PTR(-EPERM);
} else {
realfile = open_with_fake_path(&file->f_path, flags, realinode,
@@ -582,7 +582,7 @@ static long ovl_ioctl_set_flags(struct file *file, unsigned int cmd,
struct inode *inode = file_inode(file);
unsigned int oldflags;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
ret = mnt_want_write_file(file);
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 196fe3e3f02b..82f2c35894e4 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -960,7 +960,7 @@ ovl_posix_acl_xattr_set(const struct xattr_handler *handler,
goto out_acl_release;
}
err = -EPERM;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
goto out_acl_release;
posix_acl_release(acl);
diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
index ff67da201303..0a1f4bccb5da 100644
--- a/fs/overlayfs/util.c
+++ b/fs/overlayfs/util.c
@@ -481,7 +481,7 @@ struct file *ovl_path_open(struct path *path, int flags)
return ERR_PTR(err);
/* O_NOATIME is an optimization, don't fail if not permitted */
- if (inode_owner_or_capable(inode))
+ if (inode_owner_or_capable(&init_user_ns, inode))
flags |= O_NOATIME;
return dentry_open(path, flags, current_cred());
diff --git a/fs/posix_acl.c b/fs/posix_acl.c
index 5b6296cc89c4..87b5ec67000b 100644
--- a/fs/posix_acl.c
+++ b/fs/posix_acl.c
@@ -874,7 +874,7 @@ set_posix_acl(struct inode *inode, int type, struct posix_acl *acl)
if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode))
return acl ? -EACCES : 0;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
if (acl) {
diff --git a/fs/ramfs/inode.c b/fs/ramfs/inode.c
index ee179a81b3da..83641b9614bd 100644
--- a/fs/ramfs/inode.c
+++ b/fs/ramfs/inode.c
@@ -67,7 +67,7 @@ struct inode *ramfs_get_inode(struct super_block *sb,
if (inode) {
inode->i_ino = get_next_ino();
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
inode->i_mapping->a_ops = &ramfs_aops;
mapping_set_gfp_mask(inode->i_mapping, GFP_HIGHUSER);
mapping_set_unevictable(inode->i_mapping);
diff --git a/fs/reiserfs/ioctl.c b/fs/reiserfs/ioctl.c
index adb21bea3d60..4f1cbd930179 100644
--- a/fs/reiserfs/ioctl.c
+++ b/fs/reiserfs/ioctl.c
@@ -59,7 +59,7 @@ long reiserfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
if (err)
break;
- if (!inode_owner_or_capable(inode)) {
+ if (!inode_owner_or_capable(&init_user_ns, inode)) {
err = -EPERM;
goto setflags_out;
}
@@ -101,7 +101,7 @@ long reiserfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
err = put_user(inode->i_generation, (int __user *)arg);
break;
case REISERFS_IOC_SETVERSION:
- if (!inode_owner_or_capable(inode)) {
+ if (!inode_owner_or_capable(&init_user_ns, inode)) {
err = -EPERM;
break;
}
diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c
index 1594687582f0..6e43aec49b43 100644
--- a/fs/reiserfs/namei.c
+++ b/fs/reiserfs/namei.c
@@ -615,7 +615,7 @@ static int new_inode_init(struct inode *inode, struct inode *dir, umode_t mode)
* the quota init calls have to know who to charge the quota to, so
* we have to set uid and gid here
*/
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
return dquot_initialize(inode);
}
diff --git a/fs/sysv/ialloc.c b/fs/sysv/ialloc.c
index 6c9801986af6..96288d35dcb9 100644
--- a/fs/sysv/ialloc.c
+++ b/fs/sysv/ialloc.c
@@ -163,7 +163,7 @@ struct inode * sysv_new_inode(const struct inode * dir, umode_t mode)
*sbi->s_sb_fic_count = cpu_to_fs16(sbi, count);
fs16_add(sbi, sbi->s_sb_total_free_inodes, -1);
dirty_sb(sb);
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
inode->i_ino = fs16_to_cpu(sbi, ino);
inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
inode->i_blocks = 0;
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index 155521e51ac5..1639331f9543 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -94,7 +94,7 @@ struct inode *ubifs_new_inode(struct ubifs_info *c, struct inode *dir,
*/
inode->i_flags |= S_NOCMTIME;
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
inode->i_mtime = inode->i_atime = inode->i_ctime =
current_time(inode);
inode->i_mapping->nrpages = 0;
diff --git a/fs/ubifs/ioctl.c b/fs/ubifs/ioctl.c
index 4363d85a3fd4..2326d5122beb 100644
--- a/fs/ubifs/ioctl.c
+++ b/fs/ubifs/ioctl.c
@@ -155,7 +155,7 @@ long ubifs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
if (IS_RDONLY(inode))
return -EROFS;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EACCES;
if (get_user(flags, (int __user *) arg))
diff --git a/fs/udf/ialloc.c b/fs/udf/ialloc.c
index 84ed23edebfd..e2d07cc1d3c3 100644
--- a/fs/udf/ialloc.c
+++ b/fs/udf/ialloc.c
@@ -103,7 +103,7 @@ struct inode *udf_new_inode(struct inode *dir, umode_t mode)
mutex_unlock(&sbi->s_alloc_mutex);
}
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
if (UDF_QUERY_FLAG(sb, UDF_FLAG_UID_SET))
inode->i_uid = sbi->s_uid;
if (UDF_QUERY_FLAG(sb, UDF_FLAG_GID_SET))
diff --git a/fs/ufs/ialloc.c b/fs/ufs/ialloc.c
index 969fd60436d3..a04c6ea490a0 100644
--- a/fs/ufs/ialloc.c
+++ b/fs/ufs/ialloc.c
@@ -289,7 +289,7 @@ struct inode *ufs_new_inode(struct inode *dir, umode_t mode)
ufs_mark_sb_dirty(sb);
inode->i_ino = cg * uspi->s_ipg + bit;
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
inode->i_blocks = 0;
inode->i_generation = 0;
inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
diff --git a/fs/xattr.c b/fs/xattr.c
index 61a9947f62f4..fcc79c2a1ea1 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -127,7 +127,7 @@ xattr_permission(struct inode *inode, const char *name, int mask)
if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
return (mask & MAY_WRITE) ? -EPERM : -ENODATA;
if (S_ISDIR(inode->i_mode) && (inode->i_mode & S_ISVTX) &&
- (mask & MAY_WRITE) && !inode_owner_or_capable(inode))
+ (mask & MAY_WRITE) && !inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
}
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 97bd29fc8c43..218e80afc859 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1300,7 +1300,7 @@ xfs_ioctl_setattr_get_trans(
* The user ID of the calling process must be equal to the file owner
* ID, except in cases where the CAP_FSETID capability is applicable.
*/
- if (!inode_owner_or_capable(VFS_I(ip))) {
+ if (!inode_owner_or_capable(&init_user_ns, VFS_I(ip))) {
error = -EPERM;
goto out_cancel;
}
diff --git a/fs/zonefs/super.c b/fs/zonefs/super.c
index ff5930be096c..5021a41e880c 100644
--- a/fs/zonefs/super.c
+++ b/fs/zonefs/super.c
@@ -1221,7 +1221,7 @@ static void zonefs_init_dir_inode(struct inode *parent, struct inode *inode,
struct super_block *sb = parent->i_sb;
inode->i_ino = blkdev_nr_zones(sb->s_bdev->bd_disk) + type + 1;
- inode_init_owner(inode, parent, S_IFDIR | 0555);
+ inode_init_owner(inode, &init_user_ns, parent, S_IFDIR | 0555);
inode->i_op = &zonefs_dir_inode_operations;
inode->i_fop = &simple_dir_operations;
set_nlink(inode, 2);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index fa1137a232d1..61dc6378721e 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1760,7 +1760,7 @@ static inline bool sb_start_intwrite_trylock(struct super_block *sb)
}
-extern bool inode_owner_or_capable(const struct inode *inode);
+extern bool inode_owner_or_capable(struct user_namespace *user_ns, const struct inode *inode);
/*
* VFS helper functions..
@@ -1802,8 +1802,9 @@ extern long compat_ptr_ioctl(struct file *file, unsigned int cmd,
/*
* VFS file helper functions.
*/
-extern void inode_init_owner(struct inode *inode, const struct inode *dir,
- umode_t mode);
+extern void inode_init_owner(struct inode *inode,
+ struct user_namespace *user_ns,
+ const struct inode *dir, umode_t mode);
extern bool may_open_dev(const struct path *path);
/*
diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
index f1c393e5d47d..cfd2e0868f2d 100644
--- a/kernel/bpf/inode.c
+++ b/kernel/bpf/inode.c
@@ -122,7 +122,7 @@ static struct inode *bpf_get_inode(struct super_block *sb,
inode->i_mtime = inode->i_atime;
inode->i_ctime = inode->i_atime;
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
return inode;
}
diff --git a/mm/madvise.c b/mm/madvise.c
index 8afabc363b6b..a3ab05c08c28 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -539,7 +539,7 @@ static inline bool can_do_pageout(struct vm_area_struct *vma)
* otherwise we'd be including shared non-exclusive mappings, which
* opens a side channel.
*/
- return inode_owner_or_capable(file_inode(vma->vm_file)) ||
+ return inode_owner_or_capable(&init_user_ns, file_inode(vma->vm_file)) ||
inode_permission(&init_user_ns, file_inode(vma->vm_file), MAY_WRITE) == 0;
}
diff --git a/mm/mincore.c b/mm/mincore.c
index d5a58e61eac6..ad2dfb7a4500 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -166,7 +166,7 @@ static inline bool can_do_mincore(struct vm_area_struct *vma)
* for writing; otherwise we'd be including shared non-exclusive
* mappings, which opens a side channel.
*/
- return inode_owner_or_capable(file_inode(vma->vm_file)) ||
+ return inode_owner_or_capable(&init_user_ns, file_inode(vma->vm_file)) ||
inode_permission(&init_user_ns, file_inode(vma->vm_file), MAY_WRITE) == 0;
}
diff --git a/mm/shmem.c b/mm/shmem.c
index 537c137698f8..1bd6a9487222 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2303,7 +2303,7 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode
inode = new_inode(sb);
if (inode) {
inode->i_ino = ino;
- inode_init_owner(inode, dir, mode);
+ inode_init_owner(inode, &init_user_ns, dir, mode);
inode->i_blocks = 0;
inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
inode->i_generation = prandom_u32();
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 6b1826fc3658..14a195fa55eb 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3133,13 +3133,13 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
}
if (!selinux_initialized(&selinux_state))
- return (inode_owner_or_capable(inode) ? 0 : -EPERM);
+ return (inode_owner_or_capable(&init_user_ns, inode) ? 0 : -EPERM);
sbsec = inode->i_sb->s_security;
if (!(sbsec->flags & SBLABEL_MNT))
return -EOPNOTSUPP;
- if (!inode_owner_or_capable(inode))
+ if (!inode_owner_or_capable(&init_user_ns, inode))
return -EPERM;
ad.type = LSM_AUDIT_DATA_DENTRY;
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 11/38] attr: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (9 preceding siblings ...)
2020-11-28 21:34 ` [PATCH v3 10/38] inode: add idmapped mount aware init and " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 12/38] acl: " Christian Brauner
` (25 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
When file attributes are changed filesystems almost exclusively rely on the
setattr_prepare(), setattr_copy(), and notify_change() helpers for
initialization and permission checking. Let them handle idmapped mounts. If the
inode is accessed through an idmapped mount it is mapped according to the
mount's user namespace. Afterwards the checks are identical to non-idmapped
mounts. If the initial user namespace is passed nothing changes so non-idmapped
mounts will see identical behavior as before.
Helpers that perform checks on the ia_uid and ia_gid fields in struct iattr
assume that ia_uid and ia_gid are intended values and have already been mapped
correctly at the userspace-kernelspace boundary as we already do today. If the
initial user namespace is passed nothing changes so non-idmapped mounts will see
identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Don't pollute the vfs with additional helpers simply extend the existing
helpers with an additional argument and switch all callers.
/* v3 */
- kernel test robot <lkp@intel.com>:
- Adapt __setattr_copy() in fs/f2fs when CONFIG_F2FS_FS_POSIX_ACL is
selected.
---
arch/powerpc/platforms/cell/spufs/inode.c | 2 +-
drivers/base/devtmpfs.c | 4 +-
fs/9p/vfs_inode.c | 4 +-
fs/9p/vfs_inode_dotl.c | 4 +-
fs/adfs/inode.c | 2 +-
fs/affs/inode.c | 4 +-
fs/attr.c | 75 ++++++++++++++---------
fs/btrfs/inode.c | 4 +-
fs/cachefiles/interface.c | 4 +-
fs/ceph/inode.c | 2 +-
fs/cifs/inode.c | 8 +--
fs/ecryptfs/inode.c | 6 +-
fs/exfat/file.c | 4 +-
fs/ext2/inode.c | 4 +-
fs/ext4/inode.c | 4 +-
fs/f2fs/file.c | 10 +--
fs/fat/file.c | 4 +-
fs/fuse/dir.c | 2 +-
fs/gfs2/inode.c | 4 +-
fs/hfs/inode.c | 4 +-
fs/hfsplus/inode.c | 4 +-
fs/hostfs/hostfs_kern.c | 4 +-
fs/hpfs/inode.c | 4 +-
fs/hugetlbfs/inode.c | 4 +-
fs/inode.c | 2 +-
fs/jffs2/fs.c | 2 +-
fs/jfs/file.c | 4 +-
fs/kernfs/inode.c | 4 +-
fs/libfs.c | 4 +-
fs/minix/file.c | 4 +-
fs/nfsd/nfsproc.c | 2 +-
fs/nfsd/vfs.c | 4 +-
fs/nilfs2/inode.c | 4 +-
fs/ntfs/inode.c | 2 +-
fs/ocfs2/dlmfs/dlmfs.c | 4 +-
fs/ocfs2/file.c | 4 +-
fs/omfs/file.c | 4 +-
fs/open.c | 6 +-
fs/orangefs/inode.c | 4 +-
fs/overlayfs/copy_up.c | 8 +--
fs/overlayfs/dir.c | 2 +-
fs/overlayfs/inode.c | 4 +-
fs/overlayfs/super.c | 2 +-
fs/proc/base.c | 4 +-
fs/proc/generic.c | 4 +-
fs/proc/proc_sysctl.c | 4 +-
fs/ramfs/file-nommu.c | 4 +-
fs/reiserfs/inode.c | 4 +-
fs/sysv/file.c | 4 +-
fs/ubifs/file.c | 2 +-
fs/udf/file.c | 4 +-
fs/ufs/inode.c | 4 +-
fs/utimes.c | 2 +-
fs/xfs/xfs_iops.c | 2 +-
fs/zonefs/super.c | 4 +-
include/linux/fs.h | 8 ++-
mm/shmem.c | 4 +-
57 files changed, 158 insertions(+), 137 deletions(-)
diff --git a/arch/powerpc/platforms/cell/spufs/inode.c b/arch/powerpc/platforms/cell/spufs/inode.c
index 25390569e24c..3de526eb2275 100644
--- a/arch/powerpc/platforms/cell/spufs/inode.c
+++ b/arch/powerpc/platforms/cell/spufs/inode.c
@@ -98,7 +98,7 @@ spufs_setattr(struct dentry *dentry, struct iattr *attr)
if ((attr->ia_valid & ATTR_SIZE) &&
(attr->ia_size != inode->i_size))
return -EINVAL;
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c
index eac184e6d657..2e0c3cdb4184 100644
--- a/drivers/base/devtmpfs.c
+++ b/drivers/base/devtmpfs.c
@@ -221,7 +221,7 @@ static int handle_create(const char *nodename, umode_t mode, kuid_t uid,
newattrs.ia_gid = gid;
newattrs.ia_valid = ATTR_MODE|ATTR_UID|ATTR_GID;
inode_lock(d_inode(dentry));
- notify_change(dentry, &newattrs, NULL);
+ notify_change(&init_user_ns, dentry, &newattrs, NULL);
inode_unlock(d_inode(dentry));
/* mark as kernel-created inode */
@@ -328,7 +328,7 @@ static int handle_remove(const char *nodename, struct device *dev)
newattrs.ia_valid =
ATTR_UID|ATTR_GID|ATTR_MODE;
inode_lock(d_inode(dentry));
- notify_change(dentry, &newattrs, NULL);
+ notify_change(&init_user_ns, dentry, &newattrs, NULL);
inode_unlock(d_inode(dentry));
err = vfs_unlink(d_inode(parent.dentry), dentry, NULL);
if (!err || err == -ENOENT)
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index f058e89df30f..404526499c94 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -1040,7 +1040,7 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
struct p9_wstat wstat;
p9_debug(P9_DEBUG_VFS, "\n");
- retval = setattr_prepare(dentry, iattr);
+ retval = setattr_prepare(&init_user_ns, dentry, iattr);
if (retval)
return retval;
@@ -1090,7 +1090,7 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
v9fs_invalidate_inode_attr(d_inode(dentry));
- setattr_copy(d_inode(dentry), iattr);
+ setattr_copy(&init_user_ns, d_inode(dentry), iattr);
mark_inode_dirty(d_inode(dentry));
return 0;
}
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 0028eccb665a..282ec5cb45dc 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -546,7 +546,7 @@ int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
p9_debug(P9_DEBUG_VFS, "\n");
- retval = setattr_prepare(dentry, iattr);
+ retval = setattr_prepare(&init_user_ns, dentry, iattr);
if (retval)
return retval;
@@ -582,7 +582,7 @@ int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
truncate_setsize(inode, iattr->ia_size);
v9fs_invalidate_inode_attr(inode);
- setattr_copy(inode, iattr);
+ setattr_copy(&init_user_ns, inode, iattr);
mark_inode_dirty(inode);
if (iattr->ia_valid & ATTR_MODE) {
/* We also want to update ACL when we update mode bits */
diff --git a/fs/adfs/inode.c b/fs/adfs/inode.c
index 32620f4a7623..278dcee6ae22 100644
--- a/fs/adfs/inode.c
+++ b/fs/adfs/inode.c
@@ -299,7 +299,7 @@ adfs_notify_change(struct dentry *dentry, struct iattr *attr)
unsigned int ia_valid = attr->ia_valid;
int error;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
/*
* we can't change the UID or GID of any file -
diff --git a/fs/affs/inode.c b/fs/affs/inode.c
index 044412110b52..767e5bdfb703 100644
--- a/fs/affs/inode.c
+++ b/fs/affs/inode.c
@@ -223,7 +223,7 @@ affs_notify_change(struct dentry *dentry, struct iattr *attr)
pr_debug("notify_change(%lu,0x%x)\n", inode->i_ino, attr->ia_valid);
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
goto out;
@@ -249,7 +249,7 @@ affs_notify_change(struct dentry *dentry, struct iattr *attr)
affs_truncate(inode);
}
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
if (attr->ia_valid & ATTR_MODE)
diff --git a/fs/attr.c b/fs/attr.c
index 00ae0b000146..ab488f0a745a 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -18,27 +18,31 @@
#include <linux/evm.h>
#include <linux/ima.h>
-static bool chown_ok(const struct inode *inode, kuid_t uid)
+static bool chown_ok(struct user_namespace *user_ns,
+ const struct inode *inode,
+ kuid_t uid)
{
- if (uid_eq(current_fsuid(), inode->i_uid) &&
- uid_eq(uid, inode->i_uid))
+ kuid_t kuid = i_uid_into_mnt(user_ns, inode);
+ if (uid_eq(current_fsuid(), kuid) && uid_eq(uid, kuid))
return true;
- if (capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_CHOWN))
+ if (capable_wrt_inode_uidgid(user_ns, inode, CAP_CHOWN))
return true;
- if (uid_eq(inode->i_uid, INVALID_UID) &&
+ if (uid_eq(kuid, INVALID_UID) &&
ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN))
return true;
return false;
}
-static bool chgrp_ok(const struct inode *inode, kgid_t gid)
+static bool chgrp_ok(struct user_namespace *user_ns,
+ const struct inode *inode, kgid_t gid)
{
- if (uid_eq(current_fsuid(), inode->i_uid) &&
- (in_group_p(gid) || gid_eq(gid, inode->i_gid)))
+ kgid_t kgid = i_gid_into_mnt(user_ns, inode);
+ if (uid_eq(current_fsuid(), i_uid_into_mnt(user_ns, inode)) &&
+ (in_group_p(gid) || gid_eq(gid, kgid)))
return true;
- if (capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_CHOWN))
+ if (capable_wrt_inode_uidgid(user_ns, inode, CAP_CHOWN))
return true;
- if (gid_eq(inode->i_gid, INVALID_GID) &&
+ if (gid_eq(kgid, INVALID_GID) &&
ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN))
return true;
return false;
@@ -46,6 +50,7 @@ static bool chgrp_ok(const struct inode *inode, kgid_t gid)
/**
* setattr_prepare - check if attribute changes to a dentry are allowed
+ * @user_ns: user namespace of the mount
* @dentry: dentry to check
* @attr: attributes to change
*
@@ -58,7 +63,8 @@ static bool chgrp_ok(const struct inode *inode, kgid_t gid)
* Should be called as the first thing in ->setattr implementations,
* possibly after taking additional locks.
*/
-int setattr_prepare(struct dentry *dentry, struct iattr *attr)
+int setattr_prepare(struct user_namespace *user_ns, struct dentry *dentry,
+ struct iattr *attr)
{
struct inode *inode = d_inode(dentry);
unsigned int ia_valid = attr->ia_valid;
@@ -78,27 +84,27 @@ int setattr_prepare(struct dentry *dentry, struct iattr *attr)
goto kill_priv;
/* Make sure a caller can chown. */
- if ((ia_valid & ATTR_UID) && !chown_ok(inode, attr->ia_uid))
+ if ((ia_valid & ATTR_UID) && !chown_ok(user_ns, inode, attr->ia_uid))
return -EPERM;
/* Make sure caller can chgrp. */
- if ((ia_valid & ATTR_GID) && !chgrp_ok(inode, attr->ia_gid))
+ if ((ia_valid & ATTR_GID) && !chgrp_ok(user_ns, inode, attr->ia_gid))
return -EPERM;
/* Make sure a caller can chmod. */
if (ia_valid & ATTR_MODE) {
- if (!inode_owner_or_capable(&init_user_ns, inode))
+ if (!inode_owner_or_capable(user_ns, inode))
return -EPERM;
/* Also check the setgid bit! */
- if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
- inode->i_gid) &&
- !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID))
+ if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
+ i_gid_into_mnt(user_ns, inode)) &&
+ !capable_wrt_inode_uidgid(user_ns, inode, CAP_FSETID))
attr->ia_mode &= ~S_ISGID;
}
/* Check for setting the inode time. */
if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) {
- if (!inode_owner_or_capable(&init_user_ns, inode))
+ if (!inode_owner_or_capable(user_ns, inode))
return -EPERM;
}
@@ -162,20 +168,27 @@ EXPORT_SYMBOL(inode_newsize_ok);
/**
* setattr_copy - copy simple metadata updates into the generic inode
+ * @user_ns: the user namespace the inode is accessed from
* @inode: the inode to be updated
* @attr: the new attributes
*
* setattr_copy must be called with i_mutex held.
*
* setattr_copy updates the inode's metadata with that specified
- * in attr. Noticeably missing is inode size update, which is more complex
+ * in attr on idmapped mounts. If file ownership is changed setattr_copy
+ * doesn't map ia_uid and ia_gid. It will asssume the caller has already
+ * provided the intended values. Necessary permission checks to determine
+ * whether or not the S_ISGID property needs to be removed are performed with
+ * the correct idmapped mount permission helpers.
+ * Noticeably missing is inode size update, which is more complex
* as it requires pagecache updates.
*
* The inode is not marked as dirty after this operation. The rationale is
* that for "simple" filesystems, the struct inode is the inode storage.
* The caller is free to mark the inode dirty afterwards if needed.
*/
-void setattr_copy(struct inode *inode, const struct iattr *attr)
+void setattr_copy(struct user_namespace *user_ns, struct inode *inode,
+ const struct iattr *attr)
{
unsigned int ia_valid = attr->ia_valid;
@@ -191,9 +204,9 @@ void setattr_copy(struct inode *inode, const struct iattr *attr)
inode->i_ctime = attr->ia_ctime;
if (ia_valid & ATTR_MODE) {
umode_t mode = attr->ia_mode;
-
- if (!in_group_p(inode->i_gid) &&
- !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID))
+ kgid_t kgid = i_gid_into_mnt(user_ns, inode);
+ if (!in_group_p(kgid) &&
+ !capable_wrt_inode_uidgid(user_ns, inode, CAP_FSETID))
mode &= ~S_ISGID;
inode->i_mode = mode;
}
@@ -202,6 +215,7 @@ EXPORT_SYMBOL(setattr_copy);
/**
* notify_change - modify attributes of a filesytem object
+ * @user_ns: the user namespace of the mount
* @dentry: object affected
* @attr: new attributes
* @delegated_inode: returns inode, if the inode is delegated
@@ -214,13 +228,17 @@ EXPORT_SYMBOL(setattr_copy);
* retry. Because breaking a delegation may take a long time, the
* caller should drop the i_mutex before doing so.
*
+ * If file ownership is changed notify_change() doesn't map ia_uid and
+ * ia_gid. It will asssume the caller has already provided the intended values.
+ *
* Alternatively, a caller may pass NULL for delegated_inode. This may
* be appropriate for callers that expect the underlying filesystem not
* to be NFS exported. Also, passing NULL is fine for callers holding
* the file open for write, as there can be no conflicting delegation in
* that case.
*/
-int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **delegated_inode)
+int notify_change(struct user_namespace *user_ns, struct dentry *dentry,
+ struct iattr *attr, struct inode **delegated_inode)
{
struct inode *inode = dentry->d_inode;
umode_t mode = inode->i_mode;
@@ -243,9 +261,8 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
if (IS_IMMUTABLE(inode))
return -EPERM;
- if (!inode_owner_or_capable(&init_user_ns, inode)) {
- error = inode_permission(&init_user_ns, inode,
- MAY_WRITE);
+ if (!inode_owner_or_capable(user_ns, inode)) {
+ error = inode_permission(user_ns, inode, MAY_WRITE);
if (error)
return error;
}
@@ -321,9 +338,9 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
/* Don't allow modifications of files with invalid uids or
* gids unless those uids & gids are being made valid.
*/
- if (!(ia_valid & ATTR_UID) && !uid_valid(inode->i_uid))
+ if (!(ia_valid & ATTR_UID) && !uid_valid(i_uid_into_mnt(user_ns, inode)))
return -EOVERFLOW;
- if (!(ia_valid & ATTR_GID) && !gid_valid(inode->i_gid))
+ if (!(ia_valid & ATTR_GID) && !gid_valid(i_gid_into_mnt(user_ns, inode)))
return -EOVERFLOW;
error = security_inode_setattr(dentry, attr);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index ed1a5bf5f068..e65c54b7e828 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4875,7 +4875,7 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
if (btrfs_root_readonly(root))
return -EROFS;
- err = setattr_prepare(dentry, attr);
+ err = setattr_prepare(&init_user_ns, dentry, attr);
if (err)
return err;
@@ -4886,7 +4886,7 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
}
if (attr->ia_valid) {
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
inode_inc_iversion(inode);
err = btrfs_dirty_inode(inode);
diff --git a/fs/cachefiles/interface.c b/fs/cachefiles/interface.c
index 4cea5fbf695e..5efa6a3702c0 100644
--- a/fs/cachefiles/interface.c
+++ b/fs/cachefiles/interface.c
@@ -470,14 +470,14 @@ static int cachefiles_attr_changed(struct fscache_object *_object)
_debug("discard tail %llx", oi_size);
newattrs.ia_valid = ATTR_SIZE;
newattrs.ia_size = oi_size & PAGE_MASK;
- ret = notify_change(object->backer, &newattrs, NULL);
+ ret = notify_change(&init_user_ns, object->backer, &newattrs, NULL);
if (ret < 0)
goto truncate_failed;
}
newattrs.ia_valid = ATTR_SIZE;
newattrs.ia_size = ni_size;
- ret = notify_change(object->backer, &newattrs, NULL);
+ ret = notify_change(&init_user_ns, object->backer, &newattrs, NULL);
truncate_failed:
inode_unlock(d_inode(object->backer));
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index abfe42df8a1a..06645c2efa6f 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -2251,7 +2251,7 @@ int ceph_setattr(struct dentry *dentry, struct iattr *attr)
if (ceph_snap(inode) != CEPH_NOSNAP)
return -EROFS;
- err = setattr_prepare(dentry, attr);
+ err = setattr_prepare(&init_user_ns, dentry, attr);
if (err != 0)
return err;
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 9ee5f304592f..4d69b786e403 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -2602,7 +2602,7 @@ cifs_setattr_unix(struct dentry *direntry, struct iattr *attrs)
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_PERM)
attrs->ia_valid |= ATTR_FORCE;
- rc = setattr_prepare(direntry, attrs);
+ rc = setattr_prepare(&init_user_ns, direntry, attrs);
if (rc < 0)
goto out;
@@ -2707,7 +2707,7 @@ cifs_setattr_unix(struct dentry *direntry, struct iattr *attrs)
attrs->ia_size != i_size_read(inode))
truncate_setsize(inode, attrs->ia_size);
- setattr_copy(inode, attrs);
+ setattr_copy(&init_user_ns, inode, attrs);
mark_inode_dirty(inode);
/* force revalidate when any of these times are set since some
@@ -2749,7 +2749,7 @@ cifs_setattr_nounix(struct dentry *direntry, struct iattr *attrs)
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_PERM)
attrs->ia_valid |= ATTR_FORCE;
- rc = setattr_prepare(direntry, attrs);
+ rc = setattr_prepare(&init_user_ns, direntry, attrs);
if (rc < 0) {
free_xid(xid);
return rc;
@@ -2897,7 +2897,7 @@ cifs_setattr_nounix(struct dentry *direntry, struct iattr *attrs)
attrs->ia_size != i_size_read(inode))
truncate_setsize(inode, attrs->ia_size);
- setattr_copy(inode, attrs);
+ setattr_copy(&init_user_ns, inode, attrs);
mark_inode_dirty(inode);
cifs_setattr_exit:
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 9b1ae410983c..2454aef02a68 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -855,7 +855,7 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
inode_lock(d_inode(lower_dentry));
- rc = notify_change(lower_dentry, &lower_ia, NULL);
+ rc = notify_change(&init_user_ns, lower_dentry, &lower_ia, NULL);
inode_unlock(d_inode(lower_dentry));
}
return rc;
@@ -933,7 +933,7 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
}
mutex_unlock(&crypt_stat->cs_mutex);
- rc = setattr_prepare(dentry, ia);
+ rc = setattr_prepare(&init_user_ns, dentry, ia);
if (rc)
goto out;
if (ia->ia_valid & ATTR_SIZE) {
@@ -959,7 +959,7 @@ static int ecryptfs_setattr(struct dentry *dentry, struct iattr *ia)
lower_ia.ia_valid &= ~ATTR_MODE;
inode_lock(d_inode(lower_dentry));
- rc = notify_change(lower_dentry, &lower_ia, NULL);
+ rc = notify_change(&init_user_ns, lower_dentry, &lower_ia, NULL);
inode_unlock(d_inode(lower_dentry));
out:
fsstack_copy_attr_all(inode, lower_inode);
diff --git a/fs/exfat/file.c b/fs/exfat/file.c
index a92478eabfa4..ace35aa8e64b 100644
--- a/fs/exfat/file.c
+++ b/fs/exfat/file.c
@@ -305,7 +305,7 @@ int exfat_setattr(struct dentry *dentry, struct iattr *attr)
ATTR_TIMES_SET);
}
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
attr->ia_valid = ia_valid;
if (error)
goto out;
@@ -340,7 +340,7 @@ int exfat_setattr(struct dentry *dentry, struct iattr *attr)
up_write(&EXFAT_I(inode)->truncate_lock);
}
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
exfat_truncate_atime(&inode->i_atime);
mark_inode_dirty(inode);
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 11c5c6fe75bb..8eccb67d04b2 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -1668,7 +1668,7 @@ int ext2_setattr(struct dentry *dentry, struct iattr *iattr)
struct inode *inode = d_inode(dentry);
int error;
- error = setattr_prepare(dentry, iattr);
+ error = setattr_prepare(&init_user_ns, dentry, iattr);
if (error)
return error;
@@ -1688,7 +1688,7 @@ int ext2_setattr(struct dentry *dentry, struct iattr *iattr)
if (error)
return error;
}
- setattr_copy(inode, iattr);
+ setattr_copy(&init_user_ns, inode, iattr);
if (iattr->ia_valid & ATTR_MODE)
error = posix_acl_chmod(inode, inode->i_mode);
mark_inode_dirty(inode);
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 0d8385aea898..96e33198066f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5324,7 +5324,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
ATTR_GID | ATTR_TIMES_SET))))
return -EPERM;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
@@ -5499,7 +5499,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
}
if (!error) {
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
}
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 333442e96cc4..bdb5534835ab 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -825,7 +825,8 @@ int f2fs_getattr(const struct path *path, struct kstat *stat,
}
#ifdef CONFIG_F2FS_FS_POSIX_ACL
-static void __setattr_copy(struct inode *inode, const struct iattr *attr)
+static void __setattr_copy(struct user_namespace *user_ns, struct inode *inode,
+ const struct iattr *attr)
{
unsigned int ia_valid = attr->ia_valid;
@@ -841,8 +842,9 @@ static void __setattr_copy(struct inode *inode, const struct iattr *attr)
inode->i_ctime = attr->ia_ctime;
if (ia_valid & ATTR_MODE) {
umode_t mode = attr->ia_mode;
+ kgid_t kgid = i_gid_into_mnt(user_ns, inode);
- if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
+ if (!in_group_p(kgid) && !capable(CAP_FSETID))
mode &= ~S_ISGID;
set_acl_inode(inode, mode);
}
@@ -863,7 +865,7 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
!f2fs_is_compress_backend_ready(inode))
return -EOPNOTSUPP;
- err = setattr_prepare(dentry, attr);
+ err = setattr_prepare(&init_user_ns, dentry, attr);
if (err)
return err;
@@ -939,7 +941,7 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
spin_unlock(&F2FS_I(inode)->i_size_lock);
}
- __setattr_copy(inode, attr);
+ __setattr_copy(&init_user_ns, inode, attr);
if (attr->ia_valid & ATTR_MODE) {
err = posix_acl_chmod(inode, f2fs_get_inode_mode(inode));
diff --git a/fs/fat/file.c b/fs/fat/file.c
index f9ee27cf4d7c..805b501467e9 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -480,7 +480,7 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr)
attr->ia_valid &= ~TIMES_SET_FLAGS;
}
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
attr->ia_valid = ia_valid;
if (error) {
if (sbi->options.quiet)
@@ -550,7 +550,7 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr)
fat_truncate_time(inode, &attr->ia_mtime, S_MTIME);
attr->ia_valid &= ~(ATTR_ATIME|ATTR_CTIME|ATTR_MTIME);
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
out:
return error;
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 7ce7baed3f4f..dc6e8cc565d2 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -1584,7 +1584,7 @@ int fuse_do_setattr(struct dentry *dentry, struct iattr *attr,
if (!fc->default_permissions)
attr->ia_valid |= ATTR_FORCE;
- err = setattr_prepare(dentry, attr);
+ err = setattr_prepare(&init_user_ns, dentry, attr);
if (err)
return err;
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 8445588b58a6..2cf9ed1575c4 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -1860,7 +1860,7 @@ int gfs2_permission(struct inode *inode, int mask)
static int __gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
{
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
@@ -1981,7 +1981,7 @@ static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
goto error;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
goto error;
diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c
index f35a37c65e5f..c646218b72bf 100644
--- a/fs/hfs/inode.c
+++ b/fs/hfs/inode.c
@@ -608,7 +608,7 @@ int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
int error;
- error = setattr_prepare(dentry, attr); /* basic permission checks */
+ error = setattr_prepare(&init_user_ns, dentry, attr); /* basic permission checks */
if (error)
return error;
@@ -647,7 +647,7 @@ int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
current_time(inode);
}
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c
index 02d51cbcff04..a2789730f451 100644
--- a/fs/hfsplus/inode.c
+++ b/fs/hfsplus/inode.c
@@ -246,7 +246,7 @@ static int hfsplus_setattr(struct dentry *dentry, struct iattr *attr)
struct inode *inode = d_inode(dentry);
int error;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
@@ -264,7 +264,7 @@ static int hfsplus_setattr(struct dentry *dentry, struct iattr *attr)
inode->i_mtime = inode->i_ctime = current_time(inode);
}
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index 36da0c31d053..a00899c8fd52 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -792,7 +792,7 @@ static int hostfs_setattr(struct dentry *dentry, struct iattr *attr)
int fd = HOSTFS_I(inode)->fd;
- err = setattr_prepare(dentry, attr);
+ err = setattr_prepare(&init_user_ns, dentry, attr);
if (err)
return err;
@@ -849,7 +849,7 @@ static int hostfs_setattr(struct dentry *dentry, struct iattr *attr)
attr->ia_size != i_size_read(inode))
truncate_setsize(inode, attr->ia_size);
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/fs/hpfs/inode.c b/fs/hpfs/inode.c
index eb8b4baf0f2e..8ba2152a78ba 100644
--- a/fs/hpfs/inode.c
+++ b/fs/hpfs/inode.c
@@ -274,7 +274,7 @@ int hpfs_setattr(struct dentry *dentry, struct iattr *attr)
if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size > inode->i_size)
goto out_unlock;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
goto out_unlock;
@@ -288,7 +288,7 @@ int hpfs_setattr(struct dentry *dentry, struct iattr *attr)
hpfs_truncate(inode);
}
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
hpfs_write_inode(inode);
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index fed6ddfc3f3a..53d57d852073 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -761,7 +761,7 @@ static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr)
BUG_ON(!inode);
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
@@ -780,7 +780,7 @@ static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr)
return error;
}
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/fs/inode.c b/fs/inode.c
index d6dfa876c58d..66d3f7397d86 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1913,7 +1913,7 @@ static int __remove_privs(struct dentry *dentry, int kill)
* Note we call this on write, so notify_change will not
* encounter any conflicting delegations:
*/
- return notify_change(dentry, &newattrs, NULL);
+ return notify_change(&init_user_ns, dentry, &newattrs, NULL);
}
/*
diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index 78858f6e9583..67993808f4da 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -195,7 +195,7 @@ int jffs2_setattr(struct dentry *dentry, struct iattr *iattr)
struct inode *inode = d_inode(dentry);
int rc;
- rc = setattr_prepare(dentry, iattr);
+ rc = setattr_prepare(&init_user_ns, dentry, iattr);
if (rc)
return rc;
diff --git a/fs/jfs/file.c b/fs/jfs/file.c
index 930d2701f206..ff49876e9c9b 100644
--- a/fs/jfs/file.c
+++ b/fs/jfs/file.c
@@ -90,7 +90,7 @@ int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
struct inode *inode = d_inode(dentry);
int rc;
- rc = setattr_prepare(dentry, iattr);
+ rc = setattr_prepare(&init_user_ns, dentry, iattr);
if (rc)
return rc;
@@ -118,7 +118,7 @@ int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
jfs_truncate(inode);
}
- setattr_copy(inode, iattr);
+ setattr_copy(&init_user_ns, inode, iattr);
mark_inode_dirty(inode);
if (iattr->ia_valid & ATTR_MODE)
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index ff5598cc1de0..86bd4c593b78 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -122,7 +122,7 @@ int kernfs_iop_setattr(struct dentry *dentry, struct iattr *iattr)
return -EINVAL;
mutex_lock(&kernfs_mutex);
- error = setattr_prepare(dentry, iattr);
+ error = setattr_prepare(&init_user_ns, dentry, iattr);
if (error)
goto out;
@@ -131,7 +131,7 @@ int kernfs_iop_setattr(struct dentry *dentry, struct iattr *iattr)
goto out;
/* this ignores size changes */
- setattr_copy(inode, iattr);
+ setattr_copy(&init_user_ns, inode, iattr);
out:
mutex_unlock(&kernfs_mutex);
diff --git a/fs/libfs.c b/fs/libfs.c
index 23d0a00668fd..f50446576b10 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -497,13 +497,13 @@ int simple_setattr(struct dentry *dentry, struct iattr *iattr)
struct inode *inode = d_inode(dentry);
int error;
- error = setattr_prepare(dentry, iattr);
+ error = setattr_prepare(&init_user_ns, dentry, iattr);
if (error)
return error;
if (iattr->ia_valid & ATTR_SIZE)
truncate_setsize(inode, iattr->ia_size);
- setattr_copy(inode, iattr);
+ setattr_copy(&init_user_ns, inode, iattr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/fs/minix/file.c b/fs/minix/file.c
index c50b0a20fcd9..f07acd268577 100644
--- a/fs/minix/file.c
+++ b/fs/minix/file.c
@@ -27,7 +27,7 @@ static int minix_setattr(struct dentry *dentry, struct iattr *attr)
struct inode *inode = d_inode(dentry);
int error;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
@@ -41,7 +41,7 @@ static int minix_setattr(struct dentry *dentry, struct iattr *attr)
minix_truncate(inode);
}
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c
index 0d71549f9d42..aaa1dd09e243 100644
--- a/fs/nfsd/nfsproc.c
+++ b/fs/nfsd/nfsproc.c
@@ -90,7 +90,7 @@ nfsd_proc_setattr(struct svc_rqst *rqstp)
if (delta < 0)
delta = -delta;
if (delta < MAX_TOUCH_TIME_ERROR &&
- setattr_prepare(fhp->fh_dentry, iap) != 0) {
+ setattr_prepare(&init_user_ns, fhp->fh_dentry, iap) != 0) {
/*
* Turn off ATTR_[AM]TIME_SET but leave ATTR_[AM]TIME.
* This will cause notify_change to set these times
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 3cad79c3b441..e9b1452b505e 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -448,7 +448,7 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
.ia_size = iap->ia_size,
};
- host_err = notify_change(dentry, &size_attr, NULL);
+ host_err = notify_change(&init_user_ns, dentry, &size_attr, NULL);
if (host_err)
goto out_unlock;
iap->ia_valid &= ~ATTR_SIZE;
@@ -463,7 +463,7 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap,
}
iap->ia_valid |= ATTR_CTIME;
- host_err = notify_change(dentry, iap, NULL);
+ host_err = notify_change(&init_user_ns, dentry, iap, NULL);
out_unlock:
fh_unlock(fhp);
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index d286c3bf7d43..9ac47c8d27a8 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -812,7 +812,7 @@ int nilfs_setattr(struct dentry *dentry, struct iattr *iattr)
struct super_block *sb = inode->i_sb;
int err;
- err = setattr_prepare(dentry, iattr);
+ err = setattr_prepare(&init_user_ns, dentry, iattr);
if (err)
return err;
@@ -827,7 +827,7 @@ int nilfs_setattr(struct dentry *dentry, struct iattr *iattr)
nilfs_truncate(inode);
}
- setattr_copy(inode, iattr);
+ setattr_copy(&init_user_ns, inode, iattr);
mark_inode_dirty(inode);
if (iattr->ia_valid & ATTR_MODE) {
diff --git a/fs/ntfs/inode.c b/fs/ntfs/inode.c
index caf563981532..1f2ab03f4903 100644
--- a/fs/ntfs/inode.c
+++ b/fs/ntfs/inode.c
@@ -2868,7 +2868,7 @@ int ntfs_setattr(struct dentry *dentry, struct iattr *attr)
int err;
unsigned int ia_valid = attr->ia_valid;
- err = setattr_prepare(dentry, attr);
+ err = setattr_prepare(&init_user_ns, dentry, attr);
if (err)
goto out;
/* We do not support NTFS ACLs yet. */
diff --git a/fs/ocfs2/dlmfs/dlmfs.c b/fs/ocfs2/dlmfs/dlmfs.c
index 64491af88239..d5e63ca81afe 100644
--- a/fs/ocfs2/dlmfs/dlmfs.c
+++ b/fs/ocfs2/dlmfs/dlmfs.c
@@ -196,11 +196,11 @@ static int dlmfs_file_setattr(struct dentry *dentry, struct iattr *attr)
struct inode *inode = d_inode(dentry);
attr->ia_valid &= ~ATTR_SIZE;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 0c75619adf54..cabf355b148f 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1142,7 +1142,7 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
if (!(attr->ia_valid & OCFS2_VALID_ATTRS))
return 0;
- status = setattr_prepare(dentry, attr);
+ status = setattr_prepare(&init_user_ns, dentry, attr);
if (status)
return status;
@@ -1263,7 +1263,7 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
}
}
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
status = ocfs2_mark_inode_dirty(handle, inode, bh);
diff --git a/fs/omfs/file.c b/fs/omfs/file.c
index 2c7b70ee1388..729339cd7902 100644
--- a/fs/omfs/file.c
+++ b/fs/omfs/file.c
@@ -348,7 +348,7 @@ static int omfs_setattr(struct dentry *dentry, struct iattr *attr)
struct inode *inode = d_inode(dentry);
int error;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
@@ -361,7 +361,7 @@ static int omfs_setattr(struct dentry *dentry, struct iattr *attr)
omfs_truncate(inode);
}
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/fs/open.c b/fs/open.c
index b0e8430e29f3..2dc94689a7dc 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -61,7 +61,7 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
inode_lock(dentry->d_inode);
/* Note any delegations or leases have already been broken: */
- ret = notify_change(dentry, &newattrs, NULL);
+ ret = notify_change(&init_user_ns, dentry, &newattrs, NULL);
inode_unlock(dentry->d_inode);
return ret;
}
@@ -580,7 +580,7 @@ int chmod_common(const struct path *path, umode_t mode)
goto out_unlock;
newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
- error = notify_change(path->dentry, &newattrs, &delegated_inode);
+ error = notify_change(&init_user_ns, path->dentry, &newattrs, &delegated_inode);
out_unlock:
inode_unlock(inode);
if (delegated_inode) {
@@ -671,7 +671,7 @@ int chown_common(const struct path *path, uid_t user, gid_t group)
inode_lock(inode);
error = security_path_chown(path, uid, gid);
if (!error)
- error = notify_change(path->dentry, &newattrs, &delegated_inode);
+ error = notify_change(&init_user_ns, path->dentry, &newattrs, &delegated_inode);
inode_unlock(inode);
if (delegated_inode) {
error = break_deleg_wait(&delegated_inode);
diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c
index 4c790cc8042d..8ac9491ceb9a 100644
--- a/fs/orangefs/inode.c
+++ b/fs/orangefs/inode.c
@@ -855,7 +855,7 @@ int __orangefs_setattr(struct inode *inode, struct iattr *iattr)
ORANGEFS_I(inode)->attr_uid = current_fsuid();
ORANGEFS_I(inode)->attr_gid = current_fsgid();
}
- setattr_copy(inode, iattr);
+ setattr_copy(&init_user_ns, inode, iattr);
spin_unlock(&inode->i_lock);
mark_inode_dirty(inode);
@@ -876,7 +876,7 @@ int orangefs_setattr(struct dentry *dentry, struct iattr *iattr)
int ret;
gossip_debug(GOSSIP_INODE_DEBUG, "__orangefs_setattr: called on %pd\n",
dentry);
- ret = setattr_prepare(dentry, iattr);
+ ret = setattr_prepare(&init_user_ns, dentry, iattr);
if (ret)
goto out;
ret = __orangefs_setattr(d_inode(dentry), iattr);
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 955ecd4030f0..b972a58f1836 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -235,7 +235,7 @@ static int ovl_set_size(struct dentry *upperdentry, struct kstat *stat)
.ia_size = stat->size,
};
- return notify_change(upperdentry, &attr, NULL);
+ return notify_change(&init_user_ns, upperdentry, &attr, NULL);
}
static int ovl_set_timestamps(struct dentry *upperdentry, struct kstat *stat)
@@ -247,7 +247,7 @@ static int ovl_set_timestamps(struct dentry *upperdentry, struct kstat *stat)
.ia_mtime = stat->mtime,
};
- return notify_change(upperdentry, &attr, NULL);
+ return notify_change(&init_user_ns, upperdentry, &attr, NULL);
}
int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat)
@@ -259,7 +259,7 @@ int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat)
.ia_valid = ATTR_MODE,
.ia_mode = stat->mode,
};
- err = notify_change(upperdentry, &attr, NULL);
+ err = notify_change(&init_user_ns, upperdentry, &attr, NULL);
}
if (!err) {
struct iattr attr = {
@@ -267,7 +267,7 @@ int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat)
.ia_uid = stat->uid,
.ia_gid = stat->gid,
};
- err = notify_change(upperdentry, &attr, NULL);
+ err = notify_change(&init_user_ns, upperdentry, &attr, NULL);
}
if (!err)
ovl_set_timestamps(upperdentry, stat);
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 80b2fab73df7..28e4d3e4d54d 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -508,7 +508,7 @@ static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
.ia_mode = cattr->mode,
};
inode_lock(newdentry->d_inode);
- err = notify_change(newdentry, &attr, NULL);
+ err = notify_change(&init_user_ns, newdentry, &attr, NULL);
inode_unlock(newdentry->d_inode);
if (err)
goto out_cleanup;
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index c8e3c17ca131..7d1a455e4177 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -21,7 +21,7 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr)
struct dentry *upperdentry;
const struct cred *old_cred;
- err = setattr_prepare(dentry, attr);
+ err = setattr_prepare(&init_user_ns, dentry, attr);
if (err)
return err;
@@ -79,7 +79,7 @@ int ovl_setattr(struct dentry *dentry, struct iattr *attr)
inode_lock(upperdentry->d_inode);
old_cred = ovl_override_creds(dentry->d_sb);
- err = notify_change(upperdentry, attr, NULL);
+ err = notify_change(&init_user_ns, upperdentry, attr, NULL);
revert_creds(old_cred);
if (!err)
ovl_copyattr(upperdentry->d_inode, dentry->d_inode);
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 82f2c35894e4..64f5f8f6f84e 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -759,7 +759,7 @@ static struct dentry *ovl_workdir_create(struct ovl_fs *ofs,
/* Clear any inherited mode bits */
inode_lock(work->d_inode);
- err = notify_change(work, &attr, NULL);
+ err = notify_change(&init_user_ns, work, &attr, NULL);
inode_unlock(work->d_inode);
if (err)
goto out_dput;
diff --git a/fs/proc/base.c b/fs/proc/base.c
index ff7259f820c8..266b54b75c4c 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -693,11 +693,11 @@ int proc_setattr(struct dentry *dentry, struct iattr *attr)
if (attr->ia_valid & ATTR_MODE)
return -EPERM;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index b84663252add..896f2ebde75c 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -121,11 +121,11 @@ static int proc_notify_change(struct dentry *dentry, struct iattr *iattr)
struct proc_dir_entry *de = PDE(inode);
int error;
- error = setattr_prepare(dentry, iattr);
+ error = setattr_prepare(&init_user_ns, dentry, iattr);
if (error)
return error;
- setattr_copy(inode, iattr);
+ setattr_copy(&init_user_ns, inode, iattr);
mark_inode_dirty(inode);
proc_set_user(de, inode->i_uid, inode->i_gid);
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 317899222d7f..ec67dbc1f705 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -821,11 +821,11 @@ static int proc_sys_setattr(struct dentry *dentry, struct iattr *attr)
if (attr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID))
return -EPERM;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c
index 355523f4a4bf..f0358fe410d3 100644
--- a/fs/ramfs/file-nommu.c
+++ b/fs/ramfs/file-nommu.c
@@ -165,7 +165,7 @@ static int ramfs_nommu_setattr(struct dentry *dentry, struct iattr *ia)
int ret = 0;
/* POSIX UID/GID verification for setting inode attributes */
- ret = setattr_prepare(dentry, ia);
+ ret = setattr_prepare(&init_user_ns, dentry, ia);
if (ret)
return ret;
@@ -185,7 +185,7 @@ static int ramfs_nommu_setattr(struct dentry *dentry, struct iattr *ia)
}
}
- setattr_copy(inode, ia);
+ setattr_copy(&init_user_ns, inode, ia);
out:
ia->ia_valid = old_ia_valid;
return ret;
diff --git a/fs/reiserfs/inode.c b/fs/reiserfs/inode.c
index c76d563dec0e..944f2b487cf8 100644
--- a/fs/reiserfs/inode.c
+++ b/fs/reiserfs/inode.c
@@ -3288,7 +3288,7 @@ int reiserfs_setattr(struct dentry *dentry, struct iattr *attr)
unsigned int ia_valid;
int error;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
@@ -3413,7 +3413,7 @@ int reiserfs_setattr(struct dentry *dentry, struct iattr *attr)
}
if (!error) {
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
}
diff --git a/fs/sysv/file.c b/fs/sysv/file.c
index 45fc79a18594..ca7e216b7b9e 100644
--- a/fs/sysv/file.c
+++ b/fs/sysv/file.c
@@ -34,7 +34,7 @@ static int sysv_setattr(struct dentry *dentry, struct iattr *attr)
struct inode *inode = d_inode(dentry);
int error;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
@@ -47,7 +47,7 @@ static int sysv_setattr(struct dentry *dentry, struct iattr *attr)
sysv_truncate(inode);
}
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index b77d1637bbbc..25041c6d08e3 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1265,7 +1265,7 @@ int ubifs_setattr(struct dentry *dentry, struct iattr *attr)
dbg_gen("ino %lu, mode %#x, ia_valid %#x",
inode->i_ino, inode->i_mode, attr->ia_valid);
- err = setattr_prepare(dentry, attr);
+ err = setattr_prepare(&init_user_ns, dentry, attr);
if (err)
return err;
diff --git a/fs/udf/file.c b/fs/udf/file.c
index 928283925d68..0d5ade491b1a 100644
--- a/fs/udf/file.c
+++ b/fs/udf/file.c
@@ -259,7 +259,7 @@ static int udf_setattr(struct dentry *dentry, struct iattr *attr)
struct super_block *sb = inode->i_sb;
int error;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
@@ -282,7 +282,7 @@ static int udf_setattr(struct dentry *dentry, struct iattr *attr)
if (attr->ia_valid & ATTR_MODE)
udf_update_extra_perms(inode, attr->ia_mode);
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/fs/ufs/inode.c b/fs/ufs/inode.c
index c843ec858cf7..6b51f3b20143 100644
--- a/fs/ufs/inode.c
+++ b/fs/ufs/inode.c
@@ -1217,7 +1217,7 @@ int ufs_setattr(struct dentry *dentry, struct iattr *attr)
unsigned int ia_valid = attr->ia_valid;
int error;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
@@ -1227,7 +1227,7 @@ int ufs_setattr(struct dentry *dentry, struct iattr *attr)
return error;
}
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
diff --git a/fs/utimes.c b/fs/utimes.c
index fd3cc4226224..1a4130bee157 100644
--- a/fs/utimes.c
+++ b/fs/utimes.c
@@ -62,7 +62,7 @@ int vfs_utimes(const struct path *path, struct timespec64 *times)
}
retry_deleg:
inode_lock(inode);
- error = notify_change(path->dentry, &newattrs, &delegated_inode);
+ error = notify_change(&init_user_ns, path->dentry, &newattrs, &delegated_inode);
inode_unlock(inode);
if (delegated_inode) {
error = break_deleg_wait(&delegated_inode);
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 1414ab79eacf..b1be836cf35e 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -639,7 +639,7 @@ xfs_vn_change_ok(
if (XFS_FORCED_SHUTDOWN(mp))
return -EIO;
- return setattr_prepare(dentry, iattr);
+ return setattr_prepare(&init_user_ns, dentry, iattr);
}
/*
diff --git a/fs/zonefs/super.c b/fs/zonefs/super.c
index 5021a41e880c..f266e28ce00d 100644
--- a/fs/zonefs/super.c
+++ b/fs/zonefs/super.c
@@ -488,7 +488,7 @@ static int zonefs_inode_setattr(struct dentry *dentry, struct iattr *iattr)
if (unlikely(IS_IMMUTABLE(inode)))
return -EPERM;
- ret = setattr_prepare(dentry, iattr);
+ ret = setattr_prepare(&init_user_ns, dentry, iattr);
if (ret)
return ret;
@@ -516,7 +516,7 @@ static int zonefs_inode_setattr(struct dentry *dentry, struct iattr *iattr)
return ret;
}
- setattr_copy(inode, iattr);
+ setattr_copy(&init_user_ns, inode, iattr);
return 0;
}
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 61dc6378721e..ef6917e1ec75 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2803,7 +2803,8 @@ static inline int bmap(struct inode *inode, sector_t *block)
}
#endif
-extern int notify_change(struct dentry *, struct iattr *, struct inode **);
+extern int notify_change(struct user_namespace *, struct dentry *,
+ struct iattr *, struct inode **);
extern int inode_permission(struct user_namespace *, struct inode *, int);
extern int generic_permission(struct user_namespace *, struct inode *, int);
extern int __check_sticky(struct inode *dir, struct inode *inode);
@@ -3260,9 +3261,10 @@ extern int buffer_migrate_page_norefs(struct address_space *,
#define buffer_migrate_page_norefs NULL
#endif
-extern int setattr_prepare(struct dentry *, struct iattr *);
+extern int setattr_prepare(struct user_namespace *, struct dentry *, struct iattr *);
extern int inode_newsize_ok(const struct inode *, loff_t offset);
-extern void setattr_copy(struct inode *inode, const struct iattr *attr);
+extern void setattr_copy(struct user_namespace *, struct inode *inode,
+ const struct iattr *attr);
extern int file_update_time(struct file *file);
diff --git a/mm/shmem.c b/mm/shmem.c
index 1bd6a9487222..368555ddc411 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1087,7 +1087,7 @@ static int shmem_setattr(struct dentry *dentry, struct iattr *attr)
struct shmem_sb_info *sbinfo = SHMEM_SB(inode->i_sb);
int error;
- error = setattr_prepare(dentry, attr);
+ error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
return error;
@@ -1141,7 +1141,7 @@ static int shmem_setattr(struct dentry *dentry, struct iattr *attr)
}
}
- setattr_copy(inode, attr);
+ setattr_copy(&init_user_ns, inode, attr);
if (attr->ia_valid & ATTR_MODE)
error = posix_acl_chmod(inode, inode->i_mode);
return error;
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 12/38] acl: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (10 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 11/38] attr: handle idmapped mounts Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 13/38] xattr: " Christian Brauner
` (24 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
The posix acl permission checking helpers determine whether a caller is
privileged over an inode according to the acls associated with the inode.
Add helpers that make it possible to handle acls on idampped mounts.
The vfs and the filesystems targeted by this first iteration make use of
posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to
translate basic posix access and default permissions such as the ACL_USER
and ACL_GROUP type according to the initial user namespace (or the
superblock's user namespace) to and from the caller's current user
namespace. Adapt these two helpers to handle idmapped mounts whereby we
either shift from or into the mount's user namespace depending on in which
direction we're translating.
Similarly, cap_convert_nscap() is used by the vfs to translate user
namespace and non-user namespace aware filesystem capabilities from the
superblock's user namespace to the caller's user namespace. Enable it to
handle idmapped mounts by accounting for the mount's user namespace.
In addition the fileystems targeted in the first iteration of this patch
series make use of the posix_acl_chmod() and, posix_acl_update_mode()
helpers. Both helpers perform permission checks on the target inode. Let
them handle idmapped mounts. These two helpers are called when posix acls
are set by the respective filesystems to handle this case we extend the
->set() method to take an additional user namespace argument to pass the
mount's user namespace down.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Don't pollute the vfs with additional helpers simply extend the existing
helpers with an additional argument and switch all callers.
/* v3 */
unchanged
---
Documentation/filesystems/locking.rst | 6 +--
Documentation/filesystems/porting.rst | 2 +
fs/9p/acl.c | 3 +-
fs/9p/xattr.c | 1 +
fs/afs/xattr.c | 2 +
fs/btrfs/acl.c | 2 +-
fs/btrfs/inode.c | 2 +-
fs/btrfs/xattr.c | 2 +
fs/ceph/acl.c | 2 +-
fs/ceph/inode.c | 2 +-
fs/ceph/xattr.c | 1 +
fs/cifs/xattr.c | 1 +
fs/ecryptfs/inode.c | 1 +
fs/ext2/acl.c | 2 +-
fs/ext2/inode.c | 2 +-
fs/ext2/xattr_security.c | 1 +
fs/ext2/xattr_trusted.c | 1 +
fs/ext2/xattr_user.c | 1 +
fs/ext4/acl.c | 2 +-
fs/ext4/inode.c | 2 +-
fs/ext4/xattr_hurd.c | 1 +
fs/ext4/xattr_security.c | 1 +
fs/ext4/xattr_trusted.c | 1 +
fs/ext4/xattr_user.c | 1 +
fs/f2fs/acl.c | 2 +-
fs/f2fs/file.c | 2 +-
fs/f2fs/xattr.c | 2 +
fs/fuse/xattr.c | 2 +
fs/gfs2/acl.c | 2 +-
fs/gfs2/inode.c | 2 +-
fs/gfs2/xattr.c | 1 +
fs/hfs/attr.c | 1 +
fs/hfsplus/xattr.c | 1 +
fs/hfsplus/xattr_security.c | 1 +
fs/hfsplus/xattr_trusted.c | 1 +
fs/hfsplus/xattr_user.c | 1 +
fs/jffs2/acl.c | 2 +-
fs/jffs2/fs.c | 2 +-
fs/jffs2/security.c | 1 +
fs/jffs2/xattr_trusted.c | 1 +
fs/jffs2/xattr_user.c | 1 +
fs/jfs/acl.c | 2 +-
fs/jfs/file.c | 2 +-
fs/jfs/xattr.c | 2 +
fs/kernfs/inode.c | 2 +
fs/nfs/nfs4proc.c | 3 ++
fs/nfsd/nfs2acl.c | 4 +-
fs/nfsd/nfs3acl.c | 4 +-
fs/nfsd/nfs4acl.c | 4 +-
fs/ocfs2/acl.c | 2 +-
fs/ocfs2/xattr.c | 3 ++
fs/orangefs/acl.c | 2 +-
fs/orangefs/inode.c | 2 +-
fs/orangefs/xattr.c | 1 +
fs/overlayfs/super.c | 3 ++
fs/posix_acl.c | 54 +++++++++++++++++----------
fs/reiserfs/xattr_acl.c | 4 +-
fs/reiserfs/xattr_security.c | 3 +-
fs/reiserfs/xattr_trusted.c | 3 +-
fs/reiserfs/xattr_user.c | 3 +-
fs/ubifs/xattr.c | 1 +
fs/xattr.c | 10 ++---
fs/xfs/xfs_acl.c | 2 +-
fs/xfs/xfs_iops.c | 2 +-
fs/xfs/xfs_xattr.c | 3 +-
include/linux/capability.h | 3 +-
include/linux/posix_acl.h | 9 +++--
include/linux/posix_acl_xattr.h | 12 ++++--
include/linux/xattr.h | 6 +--
mm/shmem.c | 3 +-
net/socket.c | 1 +
security/commoncap.c | 17 ++++++---
72 files changed, 159 insertions(+), 80 deletions(-)
diff --git a/Documentation/filesystems/locking.rst b/Documentation/filesystems/locking.rst
index c0f2c7586531..e3b33c59b7f6 100644
--- a/Documentation/filesystems/locking.rst
+++ b/Documentation/filesystems/locking.rst
@@ -126,9 +126,9 @@ prototypes::
int (*get)(const struct xattr_handler *handler, struct dentry *dentry,
struct inode *inode, const char *name, void *buffer,
size_t size);
- int (*set)(const struct xattr_handler *handler, struct dentry *dentry,
- struct inode *inode, const char *name, const void *buffer,
- size_t size, int flags);
+ int (*set)(const struct xattr_handler *handler, struct user_namespace *user_ns,
+ struct dentry *dentry, struct inode *inode, const char *name,
+ const void *buffer, size_t size, int flags);
locking rules:
all may block
diff --git a/Documentation/filesystems/porting.rst b/Documentation/filesystems/porting.rst
index 867036aa90b8..de1dcec3b5b8 100644
--- a/Documentation/filesystems/porting.rst
+++ b/Documentation/filesystems/porting.rst
@@ -717,6 +717,8 @@ be removed. Switch while you still can; the old one won't stay.
**mandatory**
->setxattr() and xattr_handler.set() get dentry and inode passed separately.
+The xattr_handler.set() gets passed the user namespace of the mount the inode
+is seen from so filesystems can idmap the i_uid and i_gid accordingly.
dentry might be yet to be attached to inode, so do _not_ use its ->d_inode
in the instances. Rationale: !@#!@# security_d_instantiate() needs to be
called before we attach dentry to inode and !@#!@##!@$!$#!@#$!@$!@$ smack
diff --git a/fs/9p/acl.c b/fs/9p/acl.c
index d77b28e8d57a..650b14dd3ccd 100644
--- a/fs/9p/acl.c
+++ b/fs/9p/acl.c
@@ -239,6 +239,7 @@ static int v9fs_xattr_get_acl(const struct xattr_handler *handler,
}
static int v9fs_xattr_set_acl(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
@@ -279,7 +280,7 @@ static int v9fs_xattr_set_acl(const struct xattr_handler *handler,
struct iattr iattr = { 0 };
struct posix_acl *old_acl = acl;
- retval = posix_acl_update_mode(inode, &iattr.ia_mode, &acl);
+ retval = posix_acl_update_mode(user_ns, inode, &iattr.ia_mode, &acl);
if (retval)
goto err_out;
if (!acl) {
diff --git a/fs/9p/xattr.c b/fs/9p/xattr.c
index ac8ff8ca4c11..13d8cb1712d6 100644
--- a/fs/9p/xattr.c
+++ b/fs/9p/xattr.c
@@ -147,6 +147,7 @@ static int v9fs_xattr_handler_get(const struct xattr_handler *handler,
}
static int v9fs_xattr_handler_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/afs/xattr.c b/fs/afs/xattr.c
index 95c573dcda11..2ec1c6551ab6 100644
--- a/fs/afs/xattr.c
+++ b/fs/afs/xattr.c
@@ -120,6 +120,7 @@ static const struct afs_operation_ops afs_store_acl_operation = {
* Set a file's AFS3 ACL.
*/
static int afs_xattr_set_acl(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry,
struct inode *inode, const char *name,
const void *buffer, size_t size, int flags)
@@ -248,6 +249,7 @@ static const struct afs_operation_ops yfs_store_opaque_acl2_operation = {
* Set a file's YFS ACL.
*/
static int afs_xattr_set_yfs(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry,
struct inode *inode, const char *name,
const void *buffer, size_t size, int flags)
diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c
index a0af1b952c4d..b5a683e895c6 100644
--- a/fs/btrfs/acl.c
+++ b/fs/btrfs/acl.c
@@ -113,7 +113,7 @@ int btrfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
umode_t old_mode = inode->i_mode;
if (type == ACL_TYPE_ACCESS && acl) {
- ret = posix_acl_update_mode(inode, &inode->i_mode, &acl);
+ ret = posix_acl_update_mode(&init_user_ns, inode, &inode->i_mode, &acl);
if (ret)
return ret;
}
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index e65c54b7e828..e6f4aed0d311 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4891,7 +4891,7 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
err = btrfs_dirty_inode(inode);
if (!err && attr->ia_valid & ATTR_MODE)
- err = posix_acl_chmod(inode, inode->i_mode);
+ err = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
}
return err;
diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c
index 95d9aebff2c4..a6adb9decdfc 100644
--- a/fs/btrfs/xattr.c
+++ b/fs/btrfs/xattr.c
@@ -360,6 +360,7 @@ static int btrfs_xattr_handler_get(const struct xattr_handler *handler,
}
static int btrfs_xattr_handler_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *buffer,
size_t size, int flags)
@@ -369,6 +370,7 @@ static int btrfs_xattr_handler_set(const struct xattr_handler *handler,
}
static int btrfs_xattr_handler_set_prop(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/ceph/acl.c b/fs/ceph/acl.c
index e0465741c591..bceab4c01585 100644
--- a/fs/ceph/acl.c
+++ b/fs/ceph/acl.c
@@ -100,7 +100,7 @@ int ceph_set_acl(struct inode *inode, struct posix_acl *acl, int type)
case ACL_TYPE_ACCESS:
name = XATTR_NAME_POSIX_ACL_ACCESS;
if (acl) {
- ret = posix_acl_update_mode(inode, &new_mode, &acl);
+ ret = posix_acl_update_mode(&init_user_ns, inode, &new_mode, &acl);
if (ret)
goto out;
}
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 06645c2efa6f..19ec845ba5ec 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -2266,7 +2266,7 @@ int ceph_setattr(struct dentry *dentry, struct iattr *attr)
err = __ceph_setattr(inode, attr);
if (err >= 0 && (attr->ia_valid & ATTR_MODE))
- err = posix_acl_chmod(inode, attr->ia_mode);
+ err = posix_acl_chmod(&init_user_ns, inode, attr->ia_mode);
return err;
}
diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 197cb1234341..a01e0563049a 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -1163,6 +1163,7 @@ static int ceph_get_xattr_handler(const struct xattr_handler *handler,
}
static int ceph_set_xattr_handler(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/cifs/xattr.c b/fs/cifs/xattr.c
index b8299173ea7e..33935bd038aa 100644
--- a/fs/cifs/xattr.c
+++ b/fs/cifs/xattr.c
@@ -99,6 +99,7 @@ static int cifs_creation_time_set(unsigned int xid, struct cifs_tcon *pTcon,
}
static int cifs_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 2454aef02a68..28cf830f0a4d 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -1131,6 +1131,7 @@ static int ecryptfs_xattr_get(const struct xattr_handler *handler,
}
static int ecryptfs_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value, size_t size,
int flags)
diff --git a/fs/ext2/acl.c b/fs/ext2/acl.c
index cf4c77f8dd08..826987b23ccb 100644
--- a/fs/ext2/acl.c
+++ b/fs/ext2/acl.c
@@ -223,7 +223,7 @@ ext2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
umode_t mode = inode->i_mode;
if (type == ACL_TYPE_ACCESS && acl) {
- error = posix_acl_update_mode(inode, &mode, &acl);
+ error = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
if (error)
return error;
update_mode = 1;
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 8eccb67d04b2..5ff1e5e3c0fe 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -1690,7 +1690,7 @@ int ext2_setattr(struct dentry *dentry, struct iattr *iattr)
}
setattr_copy(&init_user_ns, inode, iattr);
if (iattr->ia_valid & ATTR_MODE)
- error = posix_acl_chmod(inode, inode->i_mode);
+ error = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
mark_inode_dirty(inode);
return error;
diff --git a/fs/ext2/xattr_security.c b/fs/ext2/xattr_security.c
index 9a682e440acb..f536f656b1dd 100644
--- a/fs/ext2/xattr_security.c
+++ b/fs/ext2/xattr_security.c
@@ -19,6 +19,7 @@ ext2_xattr_security_get(const struct xattr_handler *handler,
static int
ext2_xattr_security_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/ext2/xattr_trusted.c b/fs/ext2/xattr_trusted.c
index 49add1107850..2a20108a8253 100644
--- a/fs/ext2/xattr_trusted.c
+++ b/fs/ext2/xattr_trusted.c
@@ -26,6 +26,7 @@ ext2_xattr_trusted_get(const struct xattr_handler *handler,
static int
ext2_xattr_trusted_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/ext2/xattr_user.c b/fs/ext2/xattr_user.c
index c243a3b4d69d..e710f491663c 100644
--- a/fs/ext2/xattr_user.c
+++ b/fs/ext2/xattr_user.c
@@ -30,6 +30,7 @@ ext2_xattr_user_get(const struct xattr_handler *handler,
static int
ext2_xattr_user_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/ext4/acl.c b/fs/ext4/acl.c
index 68aaed48315f..4aad060010d8 100644
--- a/fs/ext4/acl.c
+++ b/fs/ext4/acl.c
@@ -245,7 +245,7 @@ ext4_set_acl(struct inode *inode, struct posix_acl *acl, int type)
ext4_fc_start_update(inode);
if ((type == ACL_TYPE_ACCESS) && acl) {
- error = posix_acl_update_mode(inode, &mode, &acl);
+ error = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
if (error)
goto out_stop;
if (mode != inode->i_mode)
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 96e33198066f..f0487795afd1 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5511,7 +5511,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
ext4_orphan_del(NULL, inode);
if (!error && (ia_valid & ATTR_MODE))
- rc = posix_acl_chmod(inode, inode->i_mode);
+ rc = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
err_out:
if (error)
diff --git a/fs/ext4/xattr_hurd.c b/fs/ext4/xattr_hurd.c
index 8cfa74a56361..74925eace7dc 100644
--- a/fs/ext4/xattr_hurd.c
+++ b/fs/ext4/xattr_hurd.c
@@ -32,6 +32,7 @@ ext4_xattr_hurd_get(const struct xattr_handler *handler,
static int
ext4_xattr_hurd_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/ext4/xattr_security.c b/fs/ext4/xattr_security.c
index 197a9d8a15ef..cf6c772200b9 100644
--- a/fs/ext4/xattr_security.c
+++ b/fs/ext4/xattr_security.c
@@ -23,6 +23,7 @@ ext4_xattr_security_get(const struct xattr_handler *handler,
static int
ext4_xattr_security_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/ext4/xattr_trusted.c b/fs/ext4/xattr_trusted.c
index e9389e5d75c3..b62112b9cb3b 100644
--- a/fs/ext4/xattr_trusted.c
+++ b/fs/ext4/xattr_trusted.c
@@ -30,6 +30,7 @@ ext4_xattr_trusted_get(const struct xattr_handler *handler,
static int
ext4_xattr_trusted_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/ext4/xattr_user.c b/fs/ext4/xattr_user.c
index d4546184b34b..6cd01df6e8a5 100644
--- a/fs/ext4/xattr_user.c
+++ b/fs/ext4/xattr_user.c
@@ -31,6 +31,7 @@ ext4_xattr_user_get(const struct xattr_handler *handler,
static int
ext4_xattr_user_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/f2fs/acl.c b/fs/f2fs/acl.c
index 306413589827..50735e8a354e 100644
--- a/fs/f2fs/acl.c
+++ b/fs/f2fs/acl.c
@@ -213,7 +213,7 @@ static int __f2fs_set_acl(struct inode *inode, int type,
case ACL_TYPE_ACCESS:
name_index = F2FS_XATTR_INDEX_POSIX_ACL_ACCESS;
if (acl && !ipage) {
- error = posix_acl_update_mode(inode, &mode, &acl);
+ error = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
if (error)
return error;
set_acl_inode(inode, mode);
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index bdb5534835ab..3633a558ddcc 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -944,7 +944,7 @@ int f2fs_setattr(struct dentry *dentry, struct iattr *attr)
__setattr_copy(&init_user_ns, inode, attr);
if (attr->ia_valid & ATTR_MODE) {
- err = posix_acl_chmod(inode, f2fs_get_inode_mode(inode));
+ err = posix_acl_chmod(&init_user_ns, inode, f2fs_get_inode_mode(inode));
if (err || is_inode_flag_set(inode, FI_ACL_MODE)) {
inode->i_mode = F2FS_I(inode)->i_acl_mode;
clear_inode_flag(inode, FI_ACL_MODE);
diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c
index d772bf13a814..2b0b270ca80e 100644
--- a/fs/f2fs/xattr.c
+++ b/fs/f2fs/xattr.c
@@ -64,6 +64,7 @@ static int f2fs_xattr_generic_get(const struct xattr_handler *handler,
}
static int f2fs_xattr_generic_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
@@ -107,6 +108,7 @@ static int f2fs_xattr_advise_get(const struct xattr_handler *handler,
}
static int f2fs_xattr_advise_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/fuse/xattr.c b/fs/fuse/xattr.c
index 371bdcbc7233..518590494fdc 100644
--- a/fs/fuse/xattr.c
+++ b/fs/fuse/xattr.c
@@ -182,6 +182,7 @@ static int fuse_xattr_get(const struct xattr_handler *handler,
}
static int fuse_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value, size_t size,
int flags)
@@ -205,6 +206,7 @@ static int no_xattr_get(const struct xattr_handler *handler,
}
static int no_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry, struct inode *nodee,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/gfs2/acl.c b/fs/gfs2/acl.c
index 2e939f5fe751..ce88ef29eef0 100644
--- a/fs/gfs2/acl.c
+++ b/fs/gfs2/acl.c
@@ -130,7 +130,7 @@ int gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
mode = inode->i_mode;
if (type == ACL_TYPE_ACCESS && acl) {
- ret = posix_acl_update_mode(inode, &mode, &acl);
+ ret = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
if (ret)
goto unlock;
}
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 2cf9ed1575c4..a29b66116c01 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -1992,7 +1992,7 @@ static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
else {
error = gfs2_setattr_simple(inode, attr);
if (!error && attr->ia_valid & ATTR_MODE)
- error = posix_acl_chmod(inode, inode->i_mode);
+ error = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
}
error:
diff --git a/fs/gfs2/xattr.c b/fs/gfs2/xattr.c
index 9d7667bc4292..8e0eb5b3528f 100644
--- a/fs/gfs2/xattr.c
+++ b/fs/gfs2/xattr.c
@@ -1214,6 +1214,7 @@ int __gfs2_xattr_set(struct inode *inode, const char *name,
}
static int gfs2_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/hfs/attr.c b/fs/hfs/attr.c
index 74fa62643136..ed2a50535bc1 100644
--- a/fs/hfs/attr.c
+++ b/fs/hfs/attr.c
@@ -121,6 +121,7 @@ static int hfs_xattr_get(const struct xattr_handler *handler,
}
static int hfs_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value, size_t size,
int flags)
diff --git a/fs/hfsplus/xattr.c b/fs/hfsplus/xattr.c
index bb0b27d88e50..0fc6000659db 100644
--- a/fs/hfsplus/xattr.c
+++ b/fs/hfsplus/xattr.c
@@ -858,6 +858,7 @@ static int hfsplus_osx_getxattr(const struct xattr_handler *handler,
}
static int hfsplus_osx_setxattr(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *buffer,
size_t size, int flags)
diff --git a/fs/hfsplus/xattr_security.c b/fs/hfsplus/xattr_security.c
index cfbe6a3bfb1e..00c82f82a1dd 100644
--- a/fs/hfsplus/xattr_security.c
+++ b/fs/hfsplus/xattr_security.c
@@ -23,6 +23,7 @@ static int hfsplus_security_getxattr(const struct xattr_handler *handler,
}
static int hfsplus_security_setxattr(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *buffer,
size_t size, int flags)
diff --git a/fs/hfsplus/xattr_trusted.c b/fs/hfsplus/xattr_trusted.c
index fbad91e1dada..e3a2712a55d1 100644
--- a/fs/hfsplus/xattr_trusted.c
+++ b/fs/hfsplus/xattr_trusted.c
@@ -22,6 +22,7 @@ static int hfsplus_trusted_getxattr(const struct xattr_handler *handler,
}
static int hfsplus_trusted_setxattr(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *buffer,
size_t size, int flags)
diff --git a/fs/hfsplus/xattr_user.c b/fs/hfsplus/xattr_user.c
index 74d19faf255e..497f8114a132 100644
--- a/fs/hfsplus/xattr_user.c
+++ b/fs/hfsplus/xattr_user.c
@@ -22,6 +22,7 @@ static int hfsplus_user_getxattr(const struct xattr_handler *handler,
}
static int hfsplus_user_setxattr(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *buffer,
size_t size, int flags)
diff --git a/fs/jffs2/acl.c b/fs/jffs2/acl.c
index 093ffbd82395..cf07a2fdf8bf 100644
--- a/fs/jffs2/acl.c
+++ b/fs/jffs2/acl.c
@@ -236,7 +236,7 @@ int jffs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
if (acl) {
umode_t mode;
- rc = posix_acl_update_mode(inode, &mode, &acl);
+ rc = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
if (rc)
return rc;
if (inode->i_mode != mode) {
diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index 67993808f4da..ee9f51bab4c6 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -201,7 +201,7 @@ int jffs2_setattr(struct dentry *dentry, struct iattr *iattr)
rc = jffs2_do_setattr(inode, iattr);
if (!rc && (iattr->ia_valid & ATTR_MODE))
- rc = posix_acl_chmod(inode, inode->i_mode);
+ rc = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
return rc;
}
diff --git a/fs/jffs2/security.c b/fs/jffs2/security.c
index c2332e30f218..451e603c61c1 100644
--- a/fs/jffs2/security.c
+++ b/fs/jffs2/security.c
@@ -57,6 +57,7 @@ static int jffs2_security_getxattr(const struct xattr_handler *handler,
}
static int jffs2_security_setxattr(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *buffer,
size_t size, int flags)
diff --git a/fs/jffs2/xattr_trusted.c b/fs/jffs2/xattr_trusted.c
index 5d6030826c52..ca1afca47910 100644
--- a/fs/jffs2/xattr_trusted.c
+++ b/fs/jffs2/xattr_trusted.c
@@ -25,6 +25,7 @@ static int jffs2_trusted_getxattr(const struct xattr_handler *handler,
}
static int jffs2_trusted_setxattr(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *buffer,
size_t size, int flags)
diff --git a/fs/jffs2/xattr_user.c b/fs/jffs2/xattr_user.c
index 9d027b4abcf9..f6bc7da9c0d3 100644
--- a/fs/jffs2/xattr_user.c
+++ b/fs/jffs2/xattr_user.c
@@ -25,6 +25,7 @@ static int jffs2_user_getxattr(const struct xattr_handler *handler,
}
static int jffs2_user_setxattr(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *buffer,
size_t size, int flags)
diff --git a/fs/jfs/acl.c b/fs/jfs/acl.c
index 92cc0ac2d1fc..cf79a34bfada 100644
--- a/fs/jfs/acl.c
+++ b/fs/jfs/acl.c
@@ -101,7 +101,7 @@ int jfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
tid = txBegin(inode->i_sb, 0);
mutex_lock(&JFS_IP(inode)->commit_mutex);
if (type == ACL_TYPE_ACCESS && acl) {
- rc = posix_acl_update_mode(inode, &mode, &acl);
+ rc = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
if (rc)
goto end_tx;
if (mode != inode->i_mode)
diff --git a/fs/jfs/file.c b/fs/jfs/file.c
index ff49876e9c9b..61c3b0c1fbf6 100644
--- a/fs/jfs/file.c
+++ b/fs/jfs/file.c
@@ -122,7 +122,7 @@ int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
mark_inode_dirty(inode);
if (iattr->ia_valid & ATTR_MODE)
- rc = posix_acl_chmod(inode, inode->i_mode);
+ rc = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
return rc;
}
diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c
index db41e7803163..2c83750bdf2b 100644
--- a/fs/jfs/xattr.c
+++ b/fs/jfs/xattr.c
@@ -932,6 +932,7 @@ static int jfs_xattr_get(const struct xattr_handler *handler,
}
static int jfs_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
@@ -950,6 +951,7 @@ static int jfs_xattr_get_os2(const struct xattr_handler *handler,
}
static int jfs_xattr_set_os2(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index 86bd4c593b78..74ee0ffcfe71 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -319,6 +319,7 @@ static int kernfs_vfs_xattr_get(const struct xattr_handler *handler,
}
static int kernfs_vfs_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *suffix, const void *value,
size_t size, int flags)
@@ -385,6 +386,7 @@ static int kernfs_vfs_user_xattr_rm(struct kernfs_node *kn,
}
static int kernfs_vfs_user_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *suffix, const void *value,
size_t size, int flags)
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 9e0ca9b2b210..77504501323c 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7486,6 +7486,7 @@ nfs4_release_lockowner(struct nfs_server *server, struct nfs4_lock_state *lsp)
#define XATTR_NAME_NFSV4_ACL "system.nfs4_acl"
static int nfs4_xattr_set_nfs4_acl(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *key, const void *buf,
size_t buflen, int flags)
@@ -7508,6 +7509,7 @@ static bool nfs4_xattr_list_nfs4_acl(struct dentry *dentry)
#ifdef CONFIG_NFS_V4_SECURITY_LABEL
static int nfs4_xattr_set_nfs4_label(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *key, const void *buf,
size_t buflen, int flags)
@@ -7558,6 +7560,7 @@ nfs4_listxattr_nfs4_label(struct inode *inode, char *list, size_t list_len)
#ifdef CONFIG_NFS_V4_2
static int nfs4_xattr_set_nfs4_user(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *key, const void *buf,
size_t buflen, int flags)
diff --git a/fs/nfsd/nfs2acl.c b/fs/nfsd/nfs2acl.c
index 6a900f770dd2..e5f06f21c24a 100644
--- a/fs/nfsd/nfs2acl.c
+++ b/fs/nfsd/nfs2acl.c
@@ -113,10 +113,10 @@ static __be32 nfsacld_proc_setacl(struct svc_rqst *rqstp)
fh_lock(fh);
- error = set_posix_acl(inode, ACL_TYPE_ACCESS, argp->acl_access);
+ error = set_posix_acl(&init_user_ns, inode, ACL_TYPE_ACCESS, argp->acl_access);
if (error)
goto out_drop_lock;
- error = set_posix_acl(inode, ACL_TYPE_DEFAULT, argp->acl_default);
+ error = set_posix_acl(&init_user_ns, inode, ACL_TYPE_DEFAULT, argp->acl_default);
if (error)
goto out_drop_lock;
diff --git a/fs/nfsd/nfs3acl.c b/fs/nfsd/nfs3acl.c
index 34a394e50e1d..3618f62e118e 100644
--- a/fs/nfsd/nfs3acl.c
+++ b/fs/nfsd/nfs3acl.c
@@ -103,10 +103,10 @@ static __be32 nfsd3_proc_setacl(struct svc_rqst *rqstp)
fh_lock(fh);
- error = set_posix_acl(inode, ACL_TYPE_ACCESS, argp->acl_access);
+ error = set_posix_acl(&init_user_ns, inode, ACL_TYPE_ACCESS, argp->acl_access);
if (error)
goto out_drop_lock;
- error = set_posix_acl(inode, ACL_TYPE_DEFAULT, argp->acl_default);
+ error = set_posix_acl(&init_user_ns, inode, ACL_TYPE_DEFAULT, argp->acl_default);
out_drop_lock:
fh_unlock(fh);
diff --git a/fs/nfsd/nfs4acl.c b/fs/nfsd/nfs4acl.c
index 71292a0d6f09..0b35bc490aee 100644
--- a/fs/nfsd/nfs4acl.c
+++ b/fs/nfsd/nfs4acl.c
@@ -781,12 +781,12 @@ nfsd4_set_nfs4_acl(struct svc_rqst *rqstp, struct svc_fh *fhp,
fh_lock(fhp);
- host_error = set_posix_acl(inode, ACL_TYPE_ACCESS, pacl);
+ host_error = set_posix_acl(&init_user_ns, inode, ACL_TYPE_ACCESS, pacl);
if (host_error < 0)
goto out_drop_lock;
if (S_ISDIR(inode->i_mode)) {
- host_error = set_posix_acl(inode, ACL_TYPE_DEFAULT, dpacl);
+ host_error = set_posix_acl(&init_user_ns, inode, ACL_TYPE_DEFAULT, dpacl);
}
out_drop_lock:
diff --git a/fs/ocfs2/acl.c b/fs/ocfs2/acl.c
index 7b07f5df3a29..7e64dbe93251 100644
--- a/fs/ocfs2/acl.c
+++ b/fs/ocfs2/acl.c
@@ -274,7 +274,7 @@ int ocfs2_iop_set_acl(struct inode *inode, struct posix_acl *acl, int type)
if (type == ACL_TYPE_ACCESS && acl) {
umode_t mode;
- status = posix_acl_update_mode(inode, &mode, &acl);
+ status = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
if (status)
goto unlock;
diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
index 9ccd19d8f7b1..7b034aef0b0d 100644
--- a/fs/ocfs2/xattr.c
+++ b/fs/ocfs2/xattr.c
@@ -7249,6 +7249,7 @@ static int ocfs2_xattr_security_get(const struct xattr_handler *handler,
}
static int ocfs2_xattr_security_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
@@ -7321,6 +7322,7 @@ static int ocfs2_xattr_trusted_get(const struct xattr_handler *handler,
}
static int ocfs2_xattr_trusted_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
@@ -7351,6 +7353,7 @@ static int ocfs2_xattr_user_get(const struct xattr_handler *handler,
}
static int ocfs2_xattr_user_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/orangefs/acl.c b/fs/orangefs/acl.c
index a25e6c890975..ba55d61906c2 100644
--- a/fs/orangefs/acl.c
+++ b/fs/orangefs/acl.c
@@ -132,7 +132,7 @@ int orangefs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
* and "mode" to the new desired value. It is up to
* us to propagate the new mode back to the server...
*/
- error = posix_acl_update_mode(inode, &iattr.ia_mode, &acl);
+ error = posix_acl_update_mode(&init_user_ns, inode, &iattr.ia_mode, &acl);
if (error) {
gossip_err("%s: posix_acl_update_mode err: %d\n",
__func__,
diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c
index 8ac9491ceb9a..563fe9ab8eb2 100644
--- a/fs/orangefs/inode.c
+++ b/fs/orangefs/inode.c
@@ -861,7 +861,7 @@ int __orangefs_setattr(struct inode *inode, struct iattr *iattr)
if (iattr->ia_valid & ATTR_MODE)
/* change mod on a file that has ACLs */
- ret = posix_acl_chmod(inode, inode->i_mode);
+ ret = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
ret = 0;
out:
diff --git a/fs/orangefs/xattr.c b/fs/orangefs/xattr.c
index bdc285aea360..41a4145ba697 100644
--- a/fs/orangefs/xattr.c
+++ b/fs/orangefs/xattr.c
@@ -526,6 +526,7 @@ ssize_t orangefs_listxattr(struct dentry *dentry, char *buffer, size_t size)
}
static int orangefs_xattr_set_default(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused,
struct inode *inode,
const char *name,
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 64f5f8f6f84e..9c12df942407 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -935,6 +935,7 @@ ovl_posix_acl_xattr_get(const struct xattr_handler *handler,
static int __maybe_unused
ovl_posix_acl_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
@@ -999,6 +1000,7 @@ static int ovl_own_xattr_get(const struct xattr_handler *handler,
}
static int ovl_own_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
@@ -1014,6 +1016,7 @@ static int ovl_other_xattr_get(const struct xattr_handler *handler,
}
static int ovl_other_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/posix_acl.c b/fs/posix_acl.c
index 87b5ec67000b..ee6c017802c3 100644
--- a/fs/posix_acl.c
+++ b/fs/posix_acl.c
@@ -559,7 +559,7 @@ __posix_acl_chmod(struct posix_acl **acl, gfp_t gfp, umode_t mode)
EXPORT_SYMBOL(__posix_acl_chmod);
int
-posix_acl_chmod(struct inode *inode, umode_t mode)
+posix_acl_chmod(struct user_namespace *user_ns, struct inode *inode, umode_t mode)
{
struct posix_acl *acl;
int ret = 0;
@@ -638,6 +638,7 @@ EXPORT_SYMBOL_GPL(posix_acl_create);
/**
* posix_acl_update_mode - update mode in set_acl
+ * @user_ns: user namespace the inode is accessed from
* @inode: target inode
* @mode_p: mode (pointer) for update
* @acl: acl pointer
@@ -651,8 +652,8 @@ EXPORT_SYMBOL_GPL(posix_acl_create);
*
* Called from set_acl inode operations.
*/
-int posix_acl_update_mode(struct inode *inode, umode_t *mode_p,
- struct posix_acl **acl)
+int posix_acl_update_mode(struct user_namespace *user_ns, struct inode *inode,
+ umode_t *mode_p, struct posix_acl **acl)
{
umode_t mode = inode->i_mode;
int error;
@@ -662,8 +663,8 @@ int posix_acl_update_mode(struct inode *inode, umode_t *mode_p,
return error;
if (error == 0)
*acl = NULL;
- if (!in_group_p(inode->i_gid) &&
- !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID))
+ if (!in_group_p(i_gid_into_mnt(user_ns, inode)) &&
+ !capable_wrt_inode_uidgid(user_ns, inode, CAP_FSETID))
mode &= ~S_ISGID;
*mode_p = mode;
return 0;
@@ -675,7 +676,8 @@ EXPORT_SYMBOL(posix_acl_update_mode);
*/
static void posix_acl_fix_xattr_userns(
struct user_namespace *to, struct user_namespace *from,
- void *value, size_t size)
+ struct user_namespace *mnt_user_ns,
+ void *value, size_t size, bool from_user)
{
struct posix_acl_xattr_header *header = value;
struct posix_acl_xattr_entry *entry = (void *)(header + 1), *end;
@@ -700,10 +702,18 @@ static void posix_acl_fix_xattr_userns(
switch(le16_to_cpu(entry->e_tag)) {
case ACL_USER:
uid = make_kuid(from, le32_to_cpu(entry->e_id));
+ if (from_user)
+ uid = kuid_from_mnt(mnt_user_ns, uid);
+ else
+ uid = kuid_into_mnt(mnt_user_ns, uid);
entry->e_id = cpu_to_le32(from_kuid(to, uid));
break;
case ACL_GROUP:
gid = make_kgid(from, le32_to_cpu(entry->e_id));
+ if (from_user)
+ gid = kgid_from_mnt(mnt_user_ns, gid);
+ else
+ gid = kgid_into_mnt(mnt_user_ns, gid);
entry->e_id = cpu_to_le32(from_kgid(to, gid));
break;
default:
@@ -712,21 +722,25 @@ static void posix_acl_fix_xattr_userns(
}
}
-void posix_acl_fix_xattr_from_user(void *value, size_t size)
+void posix_acl_fix_xattr_from_user(struct user_namespace *mnt_user_ns,
+ void *value, size_t size)
{
struct user_namespace *user_ns = current_user_ns();
- if (user_ns == &init_user_ns)
+ if ((user_ns == &init_user_ns) && (mnt_user_ns == &init_user_ns))
return;
- posix_acl_fix_xattr_userns(&init_user_ns, user_ns, value, size);
+ posix_acl_fix_xattr_userns(&init_user_ns, user_ns, mnt_user_ns, value, size, true);
}
+EXPORT_SYMBOL(posix_acl_fix_xattr_from_user);
-void posix_acl_fix_xattr_to_user(void *value, size_t size)
+void posix_acl_fix_xattr_to_user(struct user_namespace *mnt_user_ns,
+ void *value, size_t size)
{
struct user_namespace *user_ns = current_user_ns();
- if (user_ns == &init_user_ns)
+ if ((user_ns == &init_user_ns) && (mnt_user_ns == &init_user_ns))
return;
- posix_acl_fix_xattr_userns(user_ns, &init_user_ns, value, size);
+ posix_acl_fix_xattr_userns(user_ns, &init_user_ns, mnt_user_ns, value, size, false);
}
+EXPORT_SYMBOL(posix_acl_fix_xattr_to_user);
/*
* Convert from extended attribute to in-memory representation.
@@ -865,7 +879,8 @@ posix_acl_xattr_get(const struct xattr_handler *handler,
}
int
-set_posix_acl(struct inode *inode, int type, struct posix_acl *acl)
+set_posix_acl(struct user_namespace *user_ns, struct inode *inode,
+ int type, struct posix_acl *acl)
{
if (!IS_POSIXACL(inode))
return -EOPNOTSUPP;
@@ -874,7 +889,7 @@ set_posix_acl(struct inode *inode, int type, struct posix_acl *acl)
if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode))
return acl ? -EACCES : 0;
- if (!inode_owner_or_capable(&init_user_ns, inode))
+ if (!inode_owner_or_capable(user_ns, inode))
return -EPERM;
if (acl) {
@@ -888,9 +903,10 @@ EXPORT_SYMBOL(set_posix_acl);
static int
posix_acl_xattr_set(const struct xattr_handler *handler,
- struct dentry *unused, struct inode *inode,
- const char *name, const void *value,
- size_t size, int flags)
+ struct user_namespace *user_ns,
+ struct dentry *unused, struct inode *inode,
+ const char *name, const void *value, size_t size,
+ int flags)
{
struct posix_acl *acl = NULL;
int ret;
@@ -900,7 +916,7 @@ posix_acl_xattr_set(const struct xattr_handler *handler,
if (IS_ERR(acl))
return PTR_ERR(acl);
}
- ret = set_posix_acl(inode, handler->flags, acl);
+ ret = set_posix_acl(user_ns, inode, handler->flags, acl);
posix_acl_release(acl);
return ret;
}
@@ -934,7 +950,7 @@ int simple_set_acl(struct inode *inode, struct posix_acl *acl, int type)
int error;
if (type == ACL_TYPE_ACCESS) {
- error = posix_acl_update_mode(inode,
+ error = posix_acl_update_mode(&init_user_ns, inode,
&inode->i_mode, &acl);
if (error)
return error;
diff --git a/fs/reiserfs/xattr_acl.c b/fs/reiserfs/xattr_acl.c
index ccd40df6eb45..b8f397134c17 100644
--- a/fs/reiserfs/xattr_acl.c
+++ b/fs/reiserfs/xattr_acl.c
@@ -40,7 +40,7 @@ reiserfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
reiserfs_write_unlock(inode->i_sb);
if (error == 0) {
if (type == ACL_TYPE_ACCESS && acl) {
- error = posix_acl_update_mode(inode, &mode, &acl);
+ error = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
if (error)
goto unlock;
update_mode = 1;
@@ -399,5 +399,5 @@ int reiserfs_acl_chmod(struct inode *inode)
!reiserfs_posixacl(inode->i_sb))
return 0;
- return posix_acl_chmod(inode, inode->i_mode);
+ return posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
}
diff --git a/fs/reiserfs/xattr_security.c b/fs/reiserfs/xattr_security.c
index 20be9a0e5870..c98411a46c64 100644
--- a/fs/reiserfs/xattr_security.c
+++ b/fs/reiserfs/xattr_security.c
@@ -21,7 +21,8 @@ security_get(const struct xattr_handler *handler, struct dentry *unused,
}
static int
-security_set(const struct xattr_handler *handler, struct dentry *unused,
+security_set(const struct xattr_handler *handler, struct user_namespace *user_ns,
+ struct dentry *unused,
struct inode *inode, const char *name, const void *buffer,
size_t size, int flags)
{
diff --git a/fs/reiserfs/xattr_trusted.c b/fs/reiserfs/xattr_trusted.c
index 5ed48da3d02b..d197cd9da0ec 100644
--- a/fs/reiserfs/xattr_trusted.c
+++ b/fs/reiserfs/xattr_trusted.c
@@ -20,7 +20,8 @@ trusted_get(const struct xattr_handler *handler, struct dentry *unused,
}
static int
-trusted_set(const struct xattr_handler *handler, struct dentry *unused,
+trusted_set(const struct xattr_handler *handler, struct user_namespace *user_ns,
+ struct dentry *unused,
struct inode *inode, const char *name, const void *buffer,
size_t size, int flags)
{
diff --git a/fs/reiserfs/xattr_user.c b/fs/reiserfs/xattr_user.c
index a573ca45bacc..a79112aa0b4d 100644
--- a/fs/reiserfs/xattr_user.c
+++ b/fs/reiserfs/xattr_user.c
@@ -18,7 +18,8 @@ user_get(const struct xattr_handler *handler, struct dentry *unused,
}
static int
-user_set(const struct xattr_handler *handler, struct dentry *unused,
+user_set(const struct xattr_handler *handler, struct user_namespace *user_ns,
+ struct dentry *unused,
struct inode *inode, const char *name, const void *buffer,
size_t size, int flags)
{
diff --git a/fs/ubifs/xattr.c b/fs/ubifs/xattr.c
index a0b9b349efe6..87d710d0e5b1 100644
--- a/fs/ubifs/xattr.c
+++ b/fs/ubifs/xattr.c
@@ -681,6 +681,7 @@ static int xattr_get(const struct xattr_handler *handler,
}
static int xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/fs/xattr.c b/fs/xattr.c
index fcc79c2a1ea1..ff9ffe77a4b2 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -174,7 +174,7 @@ __vfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
return -EOPNOTSUPP;
if (size == 0)
value = ""; /* empty EA, do not remove */
- return handler->set(handler, dentry, inode, name, value, size, flags);
+ return handler->set(handler, &init_user_ns, dentry, inode, name, value, size, flags);
}
EXPORT_SYMBOL(__vfs_setxattr);
@@ -438,7 +438,7 @@ __vfs_removexattr(struct dentry *dentry, const char *name)
return PTR_ERR(handler);
if (!handler->set)
return -EOPNOTSUPP;
- return handler->set(handler, dentry, inode, name, NULL, 0, XATTR_REPLACE);
+ return handler->set(handler, &init_user_ns, dentry, inode, name, NULL, 0, XATTR_REPLACE);
}
EXPORT_SYMBOL(__vfs_removexattr);
@@ -536,9 +536,9 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value,
}
if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
(strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
- posix_acl_fix_xattr_from_user(kvalue, size);
+ posix_acl_fix_xattr_from_user(&init_user_ns, kvalue, size);
else if (strcmp(kname, XATTR_NAME_CAPS) == 0) {
- error = cap_convert_nscap(d, &kvalue, size);
+ error = cap_convert_nscap(&init_user_ns, d, &kvalue, size);
if (error < 0)
goto out;
size = error;
@@ -636,7 +636,7 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
if (error > 0) {
if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
(strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
- posix_acl_fix_xattr_to_user(kvalue, error);
+ posix_acl_fix_xattr_to_user(&init_user_ns, kvalue, error);
if (size && copy_to_user(value, kvalue, error))
error = -EFAULT;
} else if (error == -ERANGE && size >= XATTR_SIZE_MAX) {
diff --git a/fs/xfs/xfs_acl.c b/fs/xfs/xfs_acl.c
index c544951a0c07..2e9d2d2878ce 100644
--- a/fs/xfs/xfs_acl.c
+++ b/fs/xfs/xfs_acl.c
@@ -244,7 +244,7 @@ xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
return error;
if (type == ACL_TYPE_ACCESS) {
- error = posix_acl_update_mode(inode, &mode, &acl);
+ error = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
if (error)
return error;
set_mode = true;
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index b1be836cf35e..c5f0db50c00f 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -810,7 +810,7 @@ xfs_setattr_nonsize(
* Posix ACL code seems to care about this issue either.
*/
if ((mask & ATTR_MODE) && !(flags & XFS_ATTR_NOACL)) {
- error = posix_acl_chmod(inode, inode->i_mode);
+ error = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
if (error)
return error;
}
diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c
index bca48b308c02..76c9bdab2234 100644
--- a/fs/xfs/xfs_xattr.c
+++ b/fs/xfs/xfs_xattr.c
@@ -38,7 +38,8 @@ xfs_xattr_get(const struct xattr_handler *handler, struct dentry *unused,
}
static int
-xfs_xattr_set(const struct xattr_handler *handler, struct dentry *unused,
+xfs_xattr_set(const struct xattr_handler *handler, struct user_namespace *user_ns,
+ struct dentry *unused,
struct inode *inode, const char *name, const void *value,
size_t size, int flags)
{
diff --git a/include/linux/capability.h b/include/linux/capability.h
index 041e336f3369..0d54ca8abaed 100644
--- a/include/linux/capability.h
+++ b/include/linux/capability.h
@@ -273,6 +273,7 @@ static inline bool checkpoint_restore_ns_capable(struct user_namespace *ns)
/* audit system wants to get cap info from files as well */
extern int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps);
-extern int cap_convert_nscap(struct dentry *dentry, void **ivalue, size_t size);
+extern int cap_convert_nscap(struct user_namespace *user_ns,
+ struct dentry *dentry, void **ivalue, size_t size);
#endif /* !_LINUX_CAPABILITY_H */
diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h
index 8276baefed13..28a789218d83 100644
--- a/include/linux/posix_acl.h
+++ b/include/linux/posix_acl.h
@@ -71,13 +71,13 @@ extern int __posix_acl_create(struct posix_acl **, gfp_t, umode_t *);
extern int __posix_acl_chmod(struct posix_acl **, gfp_t, umode_t);
extern struct posix_acl *get_posix_acl(struct inode *, int);
-extern int set_posix_acl(struct inode *, int, struct posix_acl *);
+extern int set_posix_acl(struct user_namespace *, struct inode *, int, struct posix_acl *);
#ifdef CONFIG_FS_POSIX_ACL
-extern int posix_acl_chmod(struct inode *, umode_t);
+extern int posix_acl_chmod(struct user_namespace *, struct inode *, umode_t);
extern int posix_acl_create(struct inode *, umode_t *, struct posix_acl **,
struct posix_acl **);
-extern int posix_acl_update_mode(struct inode *, umode_t *, struct posix_acl **);
+extern int posix_acl_update_mode(struct user_namespace *, struct inode *, umode_t *, struct posix_acl **);
extern int simple_set_acl(struct inode *, struct posix_acl *, int);
extern int simple_acl_create(struct inode *, struct inode *);
@@ -94,7 +94,8 @@ static inline void cache_no_acl(struct inode *inode)
inode->i_default_acl = NULL;
}
#else
-static inline int posix_acl_chmod(struct inode *inode, umode_t mode)
+static inline int posix_acl_chmod(struct user_namespace *user_ns,
+ struct inode *inode, umode_t mode)
{
return 0;
}
diff --git a/include/linux/posix_acl_xattr.h b/include/linux/posix_acl_xattr.h
index 2387709991b5..9fdac573e1cb 100644
--- a/include/linux/posix_acl_xattr.h
+++ b/include/linux/posix_acl_xattr.h
@@ -33,13 +33,17 @@ posix_acl_xattr_count(size_t size)
}
#ifdef CONFIG_FS_POSIX_ACL
-void posix_acl_fix_xattr_from_user(void *value, size_t size);
-void posix_acl_fix_xattr_to_user(void *value, size_t size);
+void posix_acl_fix_xattr_from_user(struct user_namespace *mnt_user_ns,
+ void *value, size_t size);
+void posix_acl_fix_xattr_to_user(struct user_namespace *mnt_user_ns,
+ void *value, size_t size);
#else
-static inline void posix_acl_fix_xattr_from_user(void *value, size_t size)
+static inline void posix_acl_fix_xattr_from_user(struct user_namespace *mnt_user_ns,
+ void *value, size_t size)
{
}
-static inline void posix_acl_fix_xattr_to_user(void *value, size_t size)
+static inline void posix_acl_fix_xattr_to_user(struct user_namespace *mnt_user_ns,
+ void *value, size_t size)
{
}
#endif
diff --git a/include/linux/xattr.h b/include/linux/xattr.h
index 10b4dc2709f0..6d2ef03ba399 100644
--- a/include/linux/xattr.h
+++ b/include/linux/xattr.h
@@ -34,9 +34,9 @@ struct xattr_handler {
int (*get)(const struct xattr_handler *, struct dentry *dentry,
struct inode *inode, const char *name, void *buffer,
size_t size);
- int (*set)(const struct xattr_handler *, struct dentry *dentry,
- struct inode *inode, const char *name, const void *buffer,
- size_t size, int flags);
+ int (*set)(const struct xattr_handler *, struct user_namespace *user_ns,
+ struct dentry *dentry, struct inode *inode, const char *name,
+ const void *buffer, size_t size, int flags);
};
const char *xattr_full_name(const struct xattr_handler *, const char *);
diff --git a/mm/shmem.c b/mm/shmem.c
index 368555ddc411..8fdf52576e06 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1143,7 +1143,7 @@ static int shmem_setattr(struct dentry *dentry, struct iattr *attr)
setattr_copy(&init_user_ns, inode, attr);
if (attr->ia_valid & ATTR_MODE)
- error = posix_acl_chmod(inode, inode->i_mode);
+ error = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
return error;
}
@@ -3278,6 +3278,7 @@ static int shmem_xattr_handler_get(const struct xattr_handler *handler,
}
static int shmem_xattr_handler_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
diff --git a/net/socket.c b/net/socket.c
index 6e6cccc2104f..3bf36327f531 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -334,6 +334,7 @@ static const struct xattr_handler sockfs_xattr_handler = {
};
static int sockfs_security_xattr_set(const struct xattr_handler *handler,
+ struct user_namespace *user_ns,
struct dentry *dentry, struct inode *inode,
const char *suffix, const void *value,
size_t size, int flags)
diff --git a/security/commoncap.c b/security/commoncap.c
index 4cd2bdfd0a8b..abefe9223b5e 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -451,15 +451,18 @@ int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer,
}
static kuid_t rootid_from_xattr(const void *value, size_t size,
- struct user_namespace *task_ns)
+ struct user_namespace *task_ns,
+ struct user_namespace *user_ns)
{
const struct vfs_ns_cap_data *nscap = value;
+ kuid_t rootkid;
uid_t rootid = 0;
if (size == XATTR_CAPS_SZ_3)
rootid = le32_to_cpu(nscap->rootid);
- return make_kuid(task_ns, rootid);
+ rootkid = make_kuid(task_ns, rootid);
+ return kuid_from_mnt(user_ns, rootkid);
}
static bool validheader(size_t size, const struct vfs_cap_data *cap)
@@ -473,7 +476,8 @@ static bool validheader(size_t size, const struct vfs_cap_data *cap)
*
* If all is ok, we return the new size, on error return < 0.
*/
-int cap_convert_nscap(struct dentry *dentry, void **ivalue, size_t size)
+int cap_convert_nscap(struct user_namespace *user_ns, struct dentry *dentry,
+ void **ivalue, size_t size)
{
struct vfs_ns_cap_data *nscap;
uid_t nsrootid;
@@ -489,14 +493,14 @@ int cap_convert_nscap(struct dentry *dentry, void **ivalue, size_t size)
return -EINVAL;
if (!validheader(size, cap))
return -EINVAL;
- if (!capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_SETFCAP))
+ if (!capable_wrt_inode_uidgid(user_ns, inode, CAP_SETFCAP))
return -EPERM;
- if (size == XATTR_CAPS_SZ_2)
+ if (size == XATTR_CAPS_SZ_2 && (user_ns == &init_user_ns))
if (ns_capable(inode->i_sb->s_user_ns, CAP_SETFCAP))
/* user is privileged, just write the v2 */
return size;
- rootid = rootid_from_xattr(*ivalue, size, task_ns);
+ rootid = rootid_from_xattr(*ivalue, size, task_ns, user_ns);
if (!uid_valid(rootid))
return -EINVAL;
@@ -520,6 +524,7 @@ int cap_convert_nscap(struct dentry *dentry, void **ivalue, size_t size)
*ivalue = nscap;
return newsize;
}
+EXPORT_SYMBOL(cap_convert_nscap);
/*
* Calculate the new process capability sets from the capability sets attached
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 13/38] xattr: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (11 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 12/38] acl: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 14/38] commoncap: " Christian Brauner
` (23 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Tycho Andersen, Christoph Hellwig, Christian Brauner
From: Tycho Andersen <tycho@tycho.pizza>
When interacting with extended attributes the vfs verifies that the caller is
privileged over the inode with which the extended attribute is associated. For
posix access and posix default extended attributes a uid or gid can be stored
on-disk. Let the functions handle posix extended attributes on idmapped mounts.
If the inode is accessed through an idmapped mount we need to map it according
to the mount's user namespace. Afterwards the checks are identical to
non-idmapped mounts. This has no effect for e.g. security xattrs since they
don't store uids or gids and don't perform permission checks on them like posix
acls do.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Tycho Andersen <tycho@tycho.pizza>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Don't pollute the vfs with additional helpers simply extend the existing
helpers with an additional argument and switch all callers.
/* v3 */
unchanged
---
fs/cachefiles/xattr.c | 16 ++--
fs/ecryptfs/crypto.c | 4 +-
fs/ecryptfs/inode.c | 4 +-
fs/ecryptfs/mmap.c | 4 +-
fs/nfsd/vfs.c | 12 +--
fs/overlayfs/copy_up.c | 12 +--
fs/overlayfs/dir.c | 2 +-
fs/overlayfs/inode.c | 8 +-
fs/overlayfs/overlayfs.h | 6 +-
fs/overlayfs/super.c | 4 +-
fs/xattr.c | 120 +++++++++++++++-----------
include/linux/xattr.h | 24 ++++--
security/apparmor/domain.c | 4 +-
security/commoncap.c | 6 +-
security/integrity/evm/evm_crypto.c | 11 +--
security/integrity/evm/evm_main.c | 4 +-
security/integrity/ima/ima_appraise.c | 8 +-
security/selinux/hooks.c | 2 +-
security/smack/smack_lsm.c | 4 +-
19 files changed, 143 insertions(+), 112 deletions(-)
diff --git a/fs/cachefiles/xattr.c b/fs/cachefiles/xattr.c
index 72e42438f3d7..3b6a3f1610f4 100644
--- a/fs/cachefiles/xattr.c
+++ b/fs/cachefiles/xattr.c
@@ -39,7 +39,7 @@ int cachefiles_check_object_type(struct cachefiles_object *object)
_enter("%p{%s}", object, type);
/* attempt to install a type label directly */
- ret = vfs_setxattr(dentry, cachefiles_xattr_cache, type, 2,
+ ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache, type, 2,
XATTR_CREATE);
if (ret == 0) {
_debug("SET"); /* we succeeded */
@@ -54,7 +54,7 @@ int cachefiles_check_object_type(struct cachefiles_object *object)
}
/* read the current type label */
- ret = vfs_getxattr(dentry, cachefiles_xattr_cache, xtype, 3);
+ ret = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache, xtype, 3);
if (ret < 0) {
if (ret == -ERANGE)
goto bad_type_length;
@@ -110,7 +110,7 @@ int cachefiles_set_object_xattr(struct cachefiles_object *object,
_debug("SET #%u", auxdata->len);
clear_bit(FSCACHE_COOKIE_AUX_UPDATED, &object->fscache.cookie->flags);
- ret = vfs_setxattr(dentry, cachefiles_xattr_cache,
+ ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache,
&auxdata->type, auxdata->len,
XATTR_CREATE);
if (ret < 0 && ret != -ENOMEM)
@@ -140,7 +140,7 @@ int cachefiles_update_object_xattr(struct cachefiles_object *object,
_debug("SET #%u", auxdata->len);
clear_bit(FSCACHE_COOKIE_AUX_UPDATED, &object->fscache.cookie->flags);
- ret = vfs_setxattr(dentry, cachefiles_xattr_cache,
+ ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache,
&auxdata->type, auxdata->len,
XATTR_REPLACE);
if (ret < 0 && ret != -ENOMEM)
@@ -171,7 +171,7 @@ int cachefiles_check_auxdata(struct cachefiles_object *object)
if (!auxbuf)
return -ENOMEM;
- xlen = vfs_getxattr(dentry, cachefiles_xattr_cache,
+ xlen = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache,
&auxbuf->type, 512 + 1);
ret = -ESTALE;
if (xlen < 1 ||
@@ -213,7 +213,7 @@ int cachefiles_check_object_xattr(struct cachefiles_object *object,
}
/* read the current type label */
- ret = vfs_getxattr(dentry, cachefiles_xattr_cache,
+ ret = vfs_getxattr(&init_user_ns, dentry, cachefiles_xattr_cache,
&auxbuf->type, 512 + 1);
if (ret < 0) {
if (ret == -ENODATA)
@@ -270,7 +270,7 @@ int cachefiles_check_object_xattr(struct cachefiles_object *object,
}
/* update the current label */
- ret = vfs_setxattr(dentry, cachefiles_xattr_cache,
+ ret = vfs_setxattr(&init_user_ns, dentry, cachefiles_xattr_cache,
&auxdata->type, auxdata->len,
XATTR_REPLACE);
if (ret < 0) {
@@ -309,7 +309,7 @@ int cachefiles_remove_object_xattr(struct cachefiles_cache *cache,
{
int ret;
- ret = vfs_removexattr(dentry, cachefiles_xattr_cache);
+ ret = vfs_removexattr(&init_user_ns, dentry, cachefiles_xattr_cache);
if (ret < 0) {
if (ret == -ENOENT || ret == -ENODATA)
ret = 0;
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index 0681540c48d9..943e523f4c9d 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -1110,8 +1110,8 @@ ecryptfs_write_metadata_to_xattr(struct dentry *ecryptfs_dentry,
}
inode_lock(lower_inode);
- rc = __vfs_setxattr(lower_dentry, lower_inode, ECRYPTFS_XATTR_NAME,
- page_virt, size, 0);
+ rc = __vfs_setxattr(&init_user_ns, lower_dentry, lower_inode,
+ ECRYPTFS_XATTR_NAME, page_virt, size, 0);
if (!rc && ecryptfs_inode)
fsstack_copy_attr_all(ecryptfs_inode, lower_inode);
inode_unlock(lower_inode);
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 28cf830f0a4d..c35c2d2f3fe6 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -1022,7 +1022,7 @@ ecryptfs_setxattr(struct dentry *dentry, struct inode *inode,
rc = -EOPNOTSUPP;
goto out;
}
- rc = vfs_setxattr(lower_dentry, name, value, size, flags);
+ rc = vfs_setxattr(&init_user_ns, lower_dentry, name, value, size, flags);
if (!rc && inode)
fsstack_copy_attr_all(inode, d_inode(lower_dentry));
out:
@@ -1087,7 +1087,7 @@ static int ecryptfs_removexattr(struct dentry *dentry, struct inode *inode,
goto out;
}
inode_lock(lower_inode);
- rc = __vfs_removexattr(lower_dentry, name);
+ rc = __vfs_removexattr(&init_user_ns, lower_dentry, name);
inode_unlock(lower_inode);
out:
return rc;
diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c
index 019572c6b39a..2f333a40ff4d 100644
--- a/fs/ecryptfs/mmap.c
+++ b/fs/ecryptfs/mmap.c
@@ -426,8 +426,8 @@ static int ecryptfs_write_inode_size_to_xattr(struct inode *ecryptfs_inode)
if (size < 0)
size = 8;
put_unaligned_be64(i_size_read(ecryptfs_inode), xattr_virt);
- rc = __vfs_setxattr(lower_dentry, lower_inode, ECRYPTFS_XATTR_NAME,
- xattr_virt, size, 0);
+ rc = __vfs_setxattr(&init_user_ns, lower_dentry, lower_inode,
+ ECRYPTFS_XATTR_NAME, xattr_virt, size, 0);
inode_unlock(lower_inode);
if (rc)
printk(KERN_ERR "Error whilst attempting to write inode size "
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index e9b1452b505e..9a0e0e5b34f5 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -499,7 +499,7 @@ int nfsd4_is_junction(struct dentry *dentry)
return 0;
if (!(inode->i_mode & S_ISVTX))
return 0;
- if (vfs_getxattr(dentry, NFSD_JUNCTION_XATTR_NAME, NULL, 0) <= 0)
+ if (vfs_getxattr(&init_user_ns, dentry, NFSD_JUNCTION_XATTR_NAME, NULL, 0) <= 0)
return 0;
return 1;
}
@@ -2138,7 +2138,7 @@ nfsd_getxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name,
inode_lock_shared(inode);
- len = vfs_getxattr(dentry, name, NULL, 0);
+ len = vfs_getxattr(&init_user_ns, dentry, name, NULL, 0);
/*
* Zero-length attribute, just return.
@@ -2165,7 +2165,7 @@ nfsd_getxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name,
goto out;
}
- len = vfs_getxattr(dentry, name, buf, len);
+ len = vfs_getxattr(&init_user_ns, dentry, name, buf, len);
if (len <= 0) {
kvfree(buf);
buf = NULL;
@@ -2272,7 +2272,7 @@ nfsd_removexattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name)
fh_lock(fhp);
- ret = __vfs_removexattr_locked(fhp->fh_dentry, name, NULL);
+ ret = __vfs_removexattr_locked(&init_user_ns, fhp->fh_dentry, name, NULL);
fh_unlock(fhp);
fh_drop_write(fhp);
@@ -2296,8 +2296,8 @@ nfsd_setxattr(struct svc_rqst *rqstp, struct svc_fh *fhp, char *name,
return nfserrno(ret);
fh_lock(fhp);
- ret = __vfs_setxattr_locked(fhp->fh_dentry, name, buf, len, flags,
- NULL);
+ ret = __vfs_setxattr_locked(&init_user_ns, fhp->fh_dentry, name, buf,
+ len, flags, NULL);
fh_unlock(fhp);
fh_drop_write(fhp);
diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index b972a58f1836..0ad1c47e2ca2 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -85,9 +85,9 @@ int ovl_copy_xattr(struct super_block *sb, struct dentry *old,
if (ovl_is_private_xattr(sb, name))
continue;
retry:
- size = vfs_getxattr(old, name, value, value_size);
+ size = vfs_getxattr(&init_user_ns, old, name, value, value_size);
if (size == -ERANGE)
- size = vfs_getxattr(old, name, NULL, 0);
+ size = vfs_getxattr(&init_user_ns, old, name, NULL, 0);
if (size < 0) {
error = size;
@@ -114,7 +114,7 @@ int ovl_copy_xattr(struct super_block *sb, struct dentry *old,
error = 0;
continue; /* Discard */
}
- error = vfs_setxattr(new, name, value, size, 0);
+ error = vfs_setxattr(&init_user_ns, new, name, value, size, 0);
if (error) {
if (error != -EOPNOTSUPP || ovl_must_copy_xattr(name))
break;
@@ -791,7 +791,7 @@ static ssize_t ovl_getxattr(struct dentry *dentry, char *name, char **value)
ssize_t res;
char *buf;
- res = vfs_getxattr(dentry, name, NULL, 0);
+ res = vfs_getxattr(&init_user_ns, dentry, name, NULL, 0);
if (res == -ENODATA || res == -EOPNOTSUPP)
res = 0;
@@ -800,7 +800,7 @@ static ssize_t ovl_getxattr(struct dentry *dentry, char *name, char **value)
if (!buf)
return -ENOMEM;
- res = vfs_getxattr(dentry, name, buf, res);
+ res = vfs_getxattr(&init_user_ns, dentry, name, buf, res);
if (res < 0)
kfree(buf);
else
@@ -842,7 +842,7 @@ static int ovl_copy_up_meta_inode_data(struct ovl_copy_up_ctx *c)
* don't want that to happen for normal copy-up operation.
*/
if (capability) {
- err = vfs_setxattr(upperpath.dentry, XATTR_NAME_CAPS,
+ err = vfs_setxattr(&init_user_ns, upperpath.dentry, XATTR_NAME_CAPS,
capability, cap_size, 0);
if (err)
goto out_free;
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index 28e4d3e4d54d..a1794c838b78 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -449,7 +449,7 @@ static int ovl_set_upper_acl(struct dentry *upperdentry, const char *name,
if (err < 0)
goto out_free;
- err = vfs_setxattr(upperdentry, name, buffer, size, XATTR_CREATE);
+ err = vfs_setxattr(&init_user_ns, upperdentry, name, buffer, size, XATTR_CREATE);
out_free:
kfree(buffer);
return err;
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 7d1a455e4177..2835f33f386a 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -346,7 +346,7 @@ int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
goto out;
if (!value && !upperdentry) {
- err = vfs_getxattr(realdentry, name, NULL, 0);
+ err = vfs_getxattr(&init_user_ns, realdentry, name, NULL, 0);
if (err < 0)
goto out_drop_write;
}
@@ -361,10 +361,10 @@ int ovl_xattr_set(struct dentry *dentry, struct inode *inode, const char *name,
old_cred = ovl_override_creds(dentry->d_sb);
if (value)
- err = vfs_setxattr(realdentry, name, value, size, flags);
+ err = vfs_setxattr(&init_user_ns, realdentry, name, value, size, flags);
else {
WARN_ON(flags != XATTR_REPLACE);
- err = vfs_removexattr(realdentry, name);
+ err = vfs_removexattr(&init_user_ns, realdentry, name);
}
revert_creds(old_cred);
@@ -386,7 +386,7 @@ int ovl_xattr_get(struct dentry *dentry, struct inode *inode, const char *name,
ovl_i_dentry_upper(inode) ?: ovl_dentry_lower(dentry);
old_cred = ovl_override_creds(dentry->d_sb);
- res = vfs_getxattr(realdentry, name, value, size);
+ res = vfs_getxattr(&init_user_ns, realdentry, name, value, size);
revert_creds(old_cred);
return res;
}
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index f8880aa2ba0e..bf26fb3fa2c1 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -184,7 +184,7 @@ static inline ssize_t ovl_do_getxattr(struct ovl_fs *ofs, struct dentry *dentry,
size_t size)
{
const char *name = ovl_xattr(ofs, ox);
- return vfs_getxattr(dentry, name, value, size);
+ return vfs_getxattr(&init_user_ns, dentry, name, value, size);
}
static inline int ovl_do_setxattr(struct ovl_fs *ofs, struct dentry *dentry,
@@ -192,7 +192,7 @@ static inline int ovl_do_setxattr(struct ovl_fs *ofs, struct dentry *dentry,
size_t size)
{
const char *name = ovl_xattr(ofs, ox);
- int err = vfs_setxattr(dentry, name, value, size, 0);
+ int err = vfs_setxattr(&init_user_ns, dentry, name, value, size, 0);
pr_debug("setxattr(%pd2, \"%s\", \"%*pE\", %zu, 0) = %i\n",
dentry, name, min((int)size, 48), value, size, err);
return err;
@@ -202,7 +202,7 @@ static inline int ovl_do_removexattr(struct ovl_fs *ofs, struct dentry *dentry,
enum ovl_xattr ox)
{
const char *name = ovl_xattr(ofs, ox);
- int err = vfs_removexattr(dentry, name);
+ int err = vfs_removexattr(&init_user_ns, dentry, name);
pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry, name, err);
return err;
}
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 9c12df942407..4dcd092ca561 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -749,11 +749,11 @@ static struct dentry *ovl_workdir_create(struct ovl_fs *ofs,
* allowed as upper are limited to "normal" ones, where checking
* for the above two errors is sufficient.
*/
- err = vfs_removexattr(work, XATTR_NAME_POSIX_ACL_DEFAULT);
+ err = vfs_removexattr(&init_user_ns, work, XATTR_NAME_POSIX_ACL_DEFAULT);
if (err && err != -ENODATA && err != -EOPNOTSUPP)
goto out_dput;
- err = vfs_removexattr(work, XATTR_NAME_POSIX_ACL_ACCESS);
+ err = vfs_removexattr(&init_user_ns, work, XATTR_NAME_POSIX_ACL_ACCESS);
if (err && err != -ENODATA && err != -EOPNOTSUPP)
goto out_dput;
diff --git a/fs/xattr.c b/fs/xattr.c
index ff9ffe77a4b2..438fedfcd402 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -83,7 +83,8 @@ xattr_resolve_name(struct inode *inode, const char **name)
* because different namespaces have very different rules.
*/
static int
-xattr_permission(struct inode *inode, const char *name, int mask)
+xattr_permission(struct user_namespace *user_ns, struct inode *inode,
+ const char *name, int mask)
{
/*
* We can never set or remove an extended attribute on a read-only
@@ -127,11 +128,11 @@ xattr_permission(struct inode *inode, const char *name, int mask)
if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
return (mask & MAY_WRITE) ? -EPERM : -ENODATA;
if (S_ISDIR(inode->i_mode) && (inode->i_mode & S_ISVTX) &&
- (mask & MAY_WRITE) && !inode_owner_or_capable(&init_user_ns, inode))
+ (mask & MAY_WRITE) && !inode_owner_or_capable(user_ns, inode))
return -EPERM;
}
- return inode_permission(&init_user_ns, inode, mask);
+ return inode_permission(user_ns, inode, mask);
}
/*
@@ -162,8 +163,9 @@ xattr_supported_namespace(struct inode *inode, const char *prefix)
EXPORT_SYMBOL(xattr_supported_namespace);
int
-__vfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
- const void *value, size_t size, int flags)
+__vfs_setxattr(struct user_namespace *user_ns, struct dentry *dentry,
+ struct inode *inode, const char *name, const void *value,
+ size_t size, int flags)
{
const struct xattr_handler *handler;
@@ -174,7 +176,7 @@ __vfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
return -EOPNOTSUPP;
if (size == 0)
value = ""; /* empty EA, do not remove */
- return handler->set(handler, &init_user_ns, dentry, inode, name, value, size, flags);
+ return handler->set(handler, user_ns, dentry, inode, name, value, size, flags);
}
EXPORT_SYMBOL(__vfs_setxattr);
@@ -182,6 +184,7 @@ EXPORT_SYMBOL(__vfs_setxattr);
* __vfs_setxattr_noperm - perform setxattr operation without performing
* permission checks.
*
+ * @user_ns - user namespace of the mount
* @dentry - object to perform setxattr on
* @name - xattr name to set
* @value - value to set @name to
@@ -194,8 +197,9 @@ EXPORT_SYMBOL(__vfs_setxattr);
* is executed. It also assumes that the caller will make the appropriate
* permission checks.
*/
-int __vfs_setxattr_noperm(struct dentry *dentry, const char *name,
- const void *value, size_t size, int flags)
+int __vfs_setxattr_noperm(struct user_namespace *user_ns, struct dentry *dentry,
+ const char *name, const void *value, size_t size,
+ int flags)
{
struct inode *inode = dentry->d_inode;
int error = -EAGAIN;
@@ -205,7 +209,7 @@ int __vfs_setxattr_noperm(struct dentry *dentry, const char *name,
if (issec)
inode->i_flags &= ~S_NOSEC;
if (inode->i_opflags & IOP_XATTR) {
- error = __vfs_setxattr(dentry, inode, name, value, size, flags);
+ error = __vfs_setxattr(user_ns, dentry, inode, name, value, size, flags);
if (!error) {
fsnotify_xattr(dentry);
security_inode_post_setxattr(dentry, name, value,
@@ -244,14 +248,14 @@ int __vfs_setxattr_noperm(struct dentry *dentry, const char *name,
* a delegation was broken on, NULL if none.
*/
int
-__vfs_setxattr_locked(struct dentry *dentry, const char *name,
- const void *value, size_t size, int flags,
- struct inode **delegated_inode)
+__vfs_setxattr_locked(struct user_namespace *user_ns, struct dentry *dentry,
+ const char *name, const void *value, size_t size,
+ int flags, struct inode **delegated_inode)
{
struct inode *inode = dentry->d_inode;
int error;
- error = xattr_permission(inode, name, MAY_WRITE);
+ error = xattr_permission(user_ns, inode, name, MAY_WRITE);
if (error)
return error;
@@ -263,7 +267,7 @@ __vfs_setxattr_locked(struct dentry *dentry, const char *name,
if (error)
goto out;
- error = __vfs_setxattr_noperm(dentry, name, value, size, flags);
+ error = __vfs_setxattr_noperm(user_ns, dentry, name, value, size, flags);
out:
return error;
@@ -271,8 +275,8 @@ __vfs_setxattr_locked(struct dentry *dentry, const char *name,
EXPORT_SYMBOL_GPL(__vfs_setxattr_locked);
int
-vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
- size_t size, int flags)
+vfs_setxattr(struct user_namespace *user_ns, struct dentry *dentry,
+ const char *name, const void *value, size_t size, int flags)
{
struct inode *inode = dentry->d_inode;
struct inode *delegated_inode = NULL;
@@ -280,8 +284,8 @@ vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
retry_deleg:
inode_lock(inode);
- error = __vfs_setxattr_locked(dentry, name, value, size, flags,
- &delegated_inode);
+ error = __vfs_setxattr_locked(user_ns, dentry, name, value, size, flags,
+ &delegated_inode);
inode_unlock(inode);
if (delegated_inode) {
@@ -328,15 +332,16 @@ xattr_getsecurity(struct inode *inode, const char *name, void *value,
* Returns the result of alloc, if failed, or the getxattr operation.
*/
ssize_t
-vfs_getxattr_alloc(struct dentry *dentry, const char *name, char **xattr_value,
- size_t xattr_size, gfp_t flags)
+vfs_getxattr_alloc(struct user_namespace *user_ns, struct dentry *dentry,
+ const char *name, char **xattr_value, size_t xattr_size,
+ gfp_t flags)
{
const struct xattr_handler *handler;
struct inode *inode = dentry->d_inode;
char *value = *xattr_value;
int error;
- error = xattr_permission(inode, name, MAY_READ);
+ error = xattr_permission(user_ns, inode, name, MAY_READ);
if (error)
return error;
@@ -377,12 +382,13 @@ __vfs_getxattr(struct dentry *dentry, struct inode *inode, const char *name,
EXPORT_SYMBOL(__vfs_getxattr);
ssize_t
-vfs_getxattr(struct dentry *dentry, const char *name, void *value, size_t size)
+vfs_getxattr(struct user_namespace *user_ns, struct dentry *dentry,
+ const char *name, void *value, size_t size)
{
struct inode *inode = dentry->d_inode;
int error;
- error = xattr_permission(inode, name, MAY_READ);
+ error = xattr_permission(user_ns, inode, name, MAY_READ);
if (error)
return error;
@@ -428,7 +434,7 @@ vfs_listxattr(struct dentry *dentry, char *list, size_t size)
EXPORT_SYMBOL_GPL(vfs_listxattr);
int
-__vfs_removexattr(struct dentry *dentry, const char *name)
+__vfs_removexattr(struct user_namespace *user_ns, struct dentry *dentry, const char *name)
{
struct inode *inode = d_inode(dentry);
const struct xattr_handler *handler;
@@ -438,7 +444,7 @@ __vfs_removexattr(struct dentry *dentry, const char *name)
return PTR_ERR(handler);
if (!handler->set)
return -EOPNOTSUPP;
- return handler->set(handler, &init_user_ns, dentry, inode, name, NULL, 0, XATTR_REPLACE);
+ return handler->set(handler, user_ns, dentry, inode, name, NULL, 0, XATTR_REPLACE);
}
EXPORT_SYMBOL(__vfs_removexattr);
@@ -452,13 +458,13 @@ EXPORT_SYMBOL(__vfs_removexattr);
* a delegation was broken on, NULL if none.
*/
int
-__vfs_removexattr_locked(struct dentry *dentry, const char *name,
- struct inode **delegated_inode)
+__vfs_removexattr_locked(struct user_namespace *user_ns, struct dentry *dentry,
+ const char *name, struct inode **delegated_inode)
{
struct inode *inode = dentry->d_inode;
int error;
- error = xattr_permission(inode, name, MAY_WRITE);
+ error = xattr_permission(user_ns, inode, name, MAY_WRITE);
if (error)
return error;
@@ -470,7 +476,7 @@ __vfs_removexattr_locked(struct dentry *dentry, const char *name,
if (error)
goto out;
- error = __vfs_removexattr(dentry, name);
+ error = __vfs_removexattr(user_ns, dentry, name);
if (!error) {
fsnotify_xattr(dentry);
@@ -483,7 +489,8 @@ __vfs_removexattr_locked(struct dentry *dentry, const char *name,
EXPORT_SYMBOL_GPL(__vfs_removexattr_locked);
int
-vfs_removexattr(struct dentry *dentry, const char *name)
+vfs_removexattr(struct user_namespace *user_ns, struct dentry *dentry,
+ const char *name)
{
struct inode *inode = dentry->d_inode;
struct inode *delegated_inode = NULL;
@@ -491,7 +498,7 @@ vfs_removexattr(struct dentry *dentry, const char *name)
retry_deleg:
inode_lock(inode);
- error = __vfs_removexattr_locked(dentry, name, &delegated_inode);
+ error = __vfs_removexattr_locked(user_ns, dentry, name, &delegated_inode);
inode_unlock(inode);
if (delegated_inode) {
@@ -508,8 +515,9 @@ EXPORT_SYMBOL_GPL(vfs_removexattr);
* Extended attribute SET operations
*/
static long
-setxattr(struct dentry *d, const char __user *name, const void __user *value,
- size_t size, int flags)
+setxattr(struct user_namespace *user_ns, struct dentry *d,
+ const char __user *name, const void __user *value, size_t size,
+ int flags)
{
int error;
void *kvalue = NULL;
@@ -536,16 +544,16 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value,
}
if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
(strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
- posix_acl_fix_xattr_from_user(&init_user_ns, kvalue, size);
+ posix_acl_fix_xattr_from_user(user_ns, kvalue, size);
else if (strcmp(kname, XATTR_NAME_CAPS) == 0) {
- error = cap_convert_nscap(&init_user_ns, d, &kvalue, size);
+ error = cap_convert_nscap(user_ns, d, &kvalue, size);
if (error < 0)
goto out;
size = error;
}
}
- error = vfs_setxattr(d, kname, kvalue, size, flags);
+ error = vfs_setxattr(user_ns, d, kname, kvalue, size, flags);
out:
kvfree(kvalue);
@@ -558,13 +566,17 @@ static int path_setxattr(const char __user *pathname,
{
struct path path;
int error;
+
retry:
error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
if (error)
return error;
error = mnt_want_write(path.mnt);
if (!error) {
- error = setxattr(path.dentry, name, value, size, flags);
+ struct user_namespace *user_ns;
+
+ user_ns = mnt_user_ns(path.mnt);
+ error = setxattr(user_ns, path.dentry, name, value, size, flags);
mnt_drop_write(path.mnt);
}
path_put(&path);
@@ -600,7 +612,11 @@ SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name,
audit_file(f.file);
error = mnt_want_write_file(f.file);
if (!error) {
- error = setxattr(f.file->f_path.dentry, name, value, size, flags);
+ struct user_namespace *user_ns;
+
+ user_ns = mnt_user_ns(f.file->f_path.mnt);
+ error = setxattr(user_ns, f.file->f_path.dentry, name, value,
+ size, flags);
mnt_drop_write_file(f.file);
}
fdput(f);
@@ -611,8 +627,8 @@ SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name,
* Extended attribute GET operations
*/
static ssize_t
-getxattr(struct dentry *d, const char __user *name, void __user *value,
- size_t size)
+getxattr(struct user_namespace *user_ns, struct dentry *d,
+ const char __user *name, void __user *value, size_t size)
{
ssize_t error;
void *kvalue = NULL;
@@ -632,11 +648,11 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
return -ENOMEM;
}
- error = vfs_getxattr(d, kname, kvalue, size);
+ error = vfs_getxattr(user_ns, d, kname, kvalue, size);
if (error > 0) {
if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
(strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
- posix_acl_fix_xattr_to_user(&init_user_ns, kvalue, error);
+ posix_acl_fix_xattr_to_user(user_ns, kvalue, error);
if (size && copy_to_user(value, kvalue, error))
error = -EFAULT;
} else if (error == -ERANGE && size >= XATTR_SIZE_MAX) {
@@ -654,13 +670,15 @@ static ssize_t path_getxattr(const char __user *pathname,
const char __user *name, void __user *value,
size_t size, unsigned int lookup_flags)
{
+ struct user_namespace *user_ns;
struct path path;
ssize_t error;
retry:
error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path);
if (error)
return error;
- error = getxattr(path.dentry, name, value, size);
+ user_ns = mnt_user_ns(path.mnt);
+ error = getxattr(user_ns, path.dentry, name, value, size);
path_put(&path);
if (retry_estale(error, lookup_flags)) {
lookup_flags |= LOOKUP_REVAL;
@@ -684,13 +702,15 @@ SYSCALL_DEFINE4(lgetxattr, const char __user *, pathname,
SYSCALL_DEFINE4(fgetxattr, int, fd, const char __user *, name,
void __user *, value, size_t, size)
{
+ struct user_namespace *user_ns;
struct fd f = fdget(fd);
ssize_t error = -EBADF;
if (!f.file)
return error;
audit_file(f.file);
- error = getxattr(f.file->f_path.dentry, name, value, size);
+ user_ns = mnt_user_ns(f.file->f_path.mnt);
+ error = getxattr(user_ns, f.file->f_path.dentry, name, value, size);
fdput(f);
return error;
}
@@ -774,7 +794,7 @@ SYSCALL_DEFINE3(flistxattr, int, fd, char __user *, list, size_t, size)
* Extended attribute REMOVE operations
*/
static long
-removexattr(struct dentry *d, const char __user *name)
+removexattr(struct user_namespace *user_ns, struct dentry *d, const char __user *name)
{
int error;
char kname[XATTR_NAME_MAX + 1];
@@ -785,7 +805,7 @@ removexattr(struct dentry *d, const char __user *name)
if (error < 0)
return error;
- return vfs_removexattr(d, kname);
+ return vfs_removexattr(user_ns, d, kname);
}
static int path_removexattr(const char __user *pathname,
@@ -799,7 +819,9 @@ static int path_removexattr(const char __user *pathname,
return error;
error = mnt_want_write(path.mnt);
if (!error) {
- error = removexattr(path.dentry, name);
+ struct user_namespace *user_ns = mnt_user_ns(path.mnt);
+
+ error = removexattr(user_ns, path.dentry, name);
mnt_drop_write(path.mnt);
}
path_put(&path);
@@ -832,7 +854,9 @@ SYSCALL_DEFINE2(fremovexattr, int, fd, const char __user *, name)
audit_file(f.file);
error = mnt_want_write_file(f.file);
if (!error) {
- error = removexattr(f.file->f_path.dentry, name);
+ struct user_namespace *user_ns = mnt_user_ns(f.file->f_path.mnt);
+
+ error = removexattr(user_ns, f.file->f_path.dentry, name);
mnt_drop_write_file(f.file);
}
fdput(f);
diff --git a/include/linux/xattr.h b/include/linux/xattr.h
index 6d2ef03ba399..a015f5b03ef2 100644
--- a/include/linux/xattr.h
+++ b/include/linux/xattr.h
@@ -16,6 +16,7 @@
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
+#include <linux/user_namespace.h>
#include <uapi/linux/xattr.h>
struct inode;
@@ -48,18 +49,23 @@ struct xattr {
};
ssize_t __vfs_getxattr(struct dentry *, struct inode *, const char *, void *, size_t);
-ssize_t vfs_getxattr(struct dentry *, const char *, void *, size_t);
+ssize_t vfs_getxattr(struct user_namespace *, struct dentry *, const char *, void *, size_t);
ssize_t vfs_listxattr(struct dentry *d, char *list, size_t size);
-int __vfs_setxattr(struct dentry *, struct inode *, const char *, const void *, size_t, int);
-int __vfs_setxattr_noperm(struct dentry *, const char *, const void *, size_t, int);
-int __vfs_setxattr_locked(struct dentry *, const char *, const void *, size_t, int, struct inode **);
-int vfs_setxattr(struct dentry *, const char *, const void *, size_t, int);
-int __vfs_removexattr(struct dentry *, const char *);
-int __vfs_removexattr_locked(struct dentry *, const char *, struct inode **);
-int vfs_removexattr(struct dentry *, const char *);
+int __vfs_setxattr(struct user_namespace *, struct dentry *, struct inode *,
+ const char *, const void *, size_t, int);
+int __vfs_setxattr_noperm(struct user_namespace *, struct dentry *,
+ const char *, const void *, size_t, int);
+int __vfs_setxattr_locked(struct user_namespace *, struct dentry *,
+ const char *, const void *, size_t, int,
+ struct inode **);
+int vfs_setxattr(struct user_namespace *, struct dentry *, const char *, const void *, size_t, int);
+int __vfs_removexattr(struct user_namespace *, struct dentry *, const char *);
+int __vfs_removexattr_locked(struct user_namespace *, struct dentry *, const char *, struct inode **);
+int vfs_removexattr(struct user_namespace *, struct dentry *, const char *);
ssize_t generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size);
-ssize_t vfs_getxattr_alloc(struct dentry *dentry, const char *name,
+ssize_t vfs_getxattr_alloc(struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name,
char **xattr_value, size_t size, gfp_t flags);
int xattr_supported_namespace(struct inode *inode, const char *prefix);
diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c
index f919ebd042fd..16f184bc48de 100644
--- a/security/apparmor/domain.c
+++ b/security/apparmor/domain.c
@@ -324,8 +324,8 @@ static int aa_xattrs_match(const struct linux_binprm *bprm,
d = bprm->file->f_path.dentry;
for (i = 0; i < profile->xattr_count; i++) {
- size = vfs_getxattr_alloc(d, profile->xattrs[i], &value,
- value_size, GFP_KERNEL);
+ size = vfs_getxattr_alloc(&init_user_ns, d, profile->xattrs[i],
+ &value, value_size, GFP_KERNEL);
if (size >= 0) {
u32 perm;
diff --git a/security/commoncap.c b/security/commoncap.c
index abefe9223b5e..873820091b07 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -313,7 +313,7 @@ int cap_inode_killpriv(struct dentry *dentry)
{
int error;
- error = __vfs_removexattr(dentry, XATTR_NAME_CAPS);
+ error = __vfs_removexattr(&init_user_ns, dentry, XATTR_NAME_CAPS);
if (error == -EOPNOTSUPP)
error = 0;
return error;
@@ -386,8 +386,8 @@ int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer,
return -EINVAL;
size = sizeof(struct vfs_ns_cap_data);
- ret = (int) vfs_getxattr_alloc(dentry, XATTR_NAME_CAPS,
- &tmpbuf, size, GFP_NOFS);
+ ret = (int)vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_CAPS,
+ &tmpbuf, size, GFP_NOFS);
dput(dentry);
if (ret < 0)
diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c
index 168c3b78ac47..f720f78cbbb1 100644
--- a/security/integrity/evm/evm_crypto.c
+++ b/security/integrity/evm/evm_crypto.c
@@ -222,7 +222,7 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry,
ima_present = true;
continue;
}
- size = vfs_getxattr_alloc(dentry, xattr->name,
+ size = vfs_getxattr_alloc(&init_user_ns, dentry, xattr->name,
&xattr_value, xattr_size, GFP_NOFS);
if (size == -ENOMEM) {
error = -ENOMEM;
@@ -275,8 +275,8 @@ static int evm_is_immutable(struct dentry *dentry, struct inode *inode)
return 1;
/* Do this the hard way */
- rc = vfs_getxattr_alloc(dentry, XATTR_NAME_EVM, (char **)&xattr_data, 0,
- GFP_NOFS);
+ rc = vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_EVM,
+ (char **)&xattr_data, 0, GFP_NOFS);
if (rc <= 0) {
if (rc == -ENODATA)
return 0;
@@ -319,11 +319,12 @@ int evm_update_evmxattr(struct dentry *dentry, const char *xattr_name,
xattr_value_len, &data);
if (rc == 0) {
data.hdr.xattr.sha1.type = EVM_XATTR_HMAC;
- rc = __vfs_setxattr_noperm(dentry, XATTR_NAME_EVM,
+ rc = __vfs_setxattr_noperm(&init_user_ns, dentry,
+ XATTR_NAME_EVM,
&data.hdr.xattr.data[1],
SHA1_DIGEST_SIZE + 1, 0);
} else if (rc == -ENODATA && (inode->i_opflags & IOP_XATTR)) {
- rc = __vfs_removexattr(dentry, XATTR_NAME_EVM);
+ rc = __vfs_removexattr(&init_user_ns, dentry, XATTR_NAME_EVM);
}
return rc;
}
diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c
index 76d19146d74b..0de367aaa2d3 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -146,8 +146,8 @@ static enum integrity_status evm_verify_hmac(struct dentry *dentry,
/* if status is not PASS, try to check again - against -ENOMEM */
/* first need to know the sig type */
- rc = vfs_getxattr_alloc(dentry, XATTR_NAME_EVM, (char **)&xattr_data, 0,
- GFP_NOFS);
+ rc = vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_EVM,
+ (char **)&xattr_data, 0, GFP_NOFS);
if (rc <= 0) {
evm_status = INTEGRITY_FAIL;
if (rc == -ENODATA) {
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 3dd8c2e4314e..3492f0b2da1c 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -89,7 +89,7 @@ static int ima_fix_xattr(struct dentry *dentry,
iint->ima_hash->xattr.ng.type = IMA_XATTR_DIGEST_NG;
iint->ima_hash->xattr.ng.algo = algo;
}
- rc = __vfs_setxattr_noperm(dentry, XATTR_NAME_IMA,
+ rc = __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_IMA,
&iint->ima_hash->xattr.data[offset],
(sizeof(iint->ima_hash->xattr) - offset) +
iint->ima_hash->length, 0);
@@ -210,8 +210,8 @@ int ima_read_xattr(struct dentry *dentry,
{
ssize_t ret;
- ret = vfs_getxattr_alloc(dentry, XATTR_NAME_IMA, (char **)xattr_value,
- 0, GFP_NOFS);
+ ret = vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_IMA,
+ (char **)xattr_value, 0, GFP_NOFS);
if (ret == -EOPNOTSUPP)
ret = 0;
return ret;
@@ -515,7 +515,7 @@ void ima_inode_post_setattr(struct dentry *dentry)
action = ima_must_appraise(inode, MAY_ACCESS, POST_SETATTR);
if (!action)
- __vfs_removexattr(dentry, XATTR_NAME_IMA);
+ __vfs_removexattr(&init_user_ns, dentry, XATTR_NAME_IMA);
iint = integrity_iint_find(inode);
if (iint) {
set_bit(IMA_CHANGE_ATTR, &iint->atomic_flags);
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 14a195fa55eb..3f42950feed0 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -6518,7 +6518,7 @@ static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen
*/
static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
{
- return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
+ return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
}
static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 5c90b9fa4d40..11003244b18b 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -3425,7 +3425,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
*/
if (isp->smk_flags & SMK_INODE_CHANGED) {
isp->smk_flags &= ~SMK_INODE_CHANGED;
- rc = __vfs_setxattr(dp, inode,
+ rc = __vfs_setxattr(&init_user_ns, dp, inode,
XATTR_NAME_SMACKTRANSMUTE,
TRANS_TRUE, TRANS_TRUE_SIZE,
0);
@@ -4603,7 +4603,7 @@ static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
{
- return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
+ return __vfs_setxattr_noperm(&init_user_ns, dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0);
}
static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 14/38] commoncap: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (12 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 13/38] xattr: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 15/38] stat: " Christian Brauner
` (22 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
When interacting with user namespace and non-user namespace aware filesystem
capabilities the vfs will perform various security checks to determine whether
or not the filesystem capabilities can be used by the caller (e.g. during exec),
or even whether they need to be removed. The main infrastructure for this
resides in the capability codepaths but they are called through the LSM security
infrastructure even though they are not technically an LSM or optional. This
extends the existing security hooks security_inode_removexattr(),
security_inode_killpriv(), security_inode_getsecurity() to pass down the mount's
user namespace and makes them aware of idmapped mounts.
In order to actually get filesystem capabilities from disk the capability
infrastructure exposes the get_vfs_caps_from_disk() helper. For user namespace
aware filesystem capabilities a root uid is stored alongside the capabilities.
In order to determine whether the caller can make use of the filesystem
capability or whether it needs to be ignored it is translated according to the
superblock's user namespace. If it can be translated to uid 0 according to that
id mapping the caller can use the filesystem capabilities stored on disk. If we
are accessing the inode that holds the filesystem capabilities through an
idmapped mount we need to map the root uid according to the mount's user
namespace.
Afterwards the checks are identical to non-idmapped mounts. Reading
filesystem caps from disk enforces that the root uid associated with the
filesystem capability must have a mapping in the superblock's user
namespace and that the caller is either in the same user namespace or is a
descendant of the superblock's user namespace. For filesystems that are
mountable inside user namespace the caller can just mount the filesystem
and won't usually need to idmap it. If they do want to idmap it they can create
an idmapped mount and mark it with a user namespace they created and which is
thus a descendant of s_user_ns. For filesystems that are not mountable inside
user namespaces the descendant rule is trivially true because the s_user_ns will
be the initial user namespace.
If the initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Don't pollute the vfs with additional helpers simply extend the existing
helpers with an additional argument and switch all callers.
/* v3 */
- Paul Moore <paul@paul-moore.com>:
- All audit logging is currently based on init_user_ns and will remain so
until other work unrelated to this patchset has landed so always pass
&init_user_ns in audit.
---
fs/attr.c | 2 +-
fs/xattr.c | 14 +++++------
include/linux/capability.h | 4 +++-
include/linux/lsm_hook_defs.h | 15 +++++++-----
include/linux/lsm_hooks.h | 1 +
include/linux/security.h | 44 +++++++++++++++++++++++------------
kernel/auditsc.c | 5 ++--
security/commoncap.c | 30 +++++++++++++++---------
security/security.c | 25 ++++++++++++--------
security/selinux/hooks.c | 20 +++++++++-------
security/smack/smack_lsm.c | 14 ++++++-----
11 files changed, 107 insertions(+), 67 deletions(-)
diff --git a/fs/attr.c b/fs/attr.c
index ab488f0a745a..e86d72608b9f 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -113,7 +113,7 @@ int setattr_prepare(struct user_namespace *user_ns, struct dentry *dentry,
if (ia_valid & ATTR_KILL_PRIV) {
int error;
- error = security_inode_killpriv(dentry);
+ error = security_inode_killpriv(user_ns, dentry);
if (error)
return error;
}
diff --git a/fs/xattr.c b/fs/xattr.c
index 438fedfcd402..8c50b2a935e4 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -259,7 +259,7 @@ __vfs_setxattr_locked(struct user_namespace *user_ns, struct dentry *dentry,
if (error)
return error;
- error = security_inode_setxattr(dentry, name, value, size, flags);
+ error = security_inode_setxattr(user_ns, dentry, name, value, size, flags);
if (error)
goto out;
@@ -298,18 +298,18 @@ vfs_setxattr(struct user_namespace *user_ns, struct dentry *dentry,
EXPORT_SYMBOL_GPL(vfs_setxattr);
static ssize_t
-xattr_getsecurity(struct inode *inode, const char *name, void *value,
- size_t size)
+xattr_getsecurity(struct user_namespace *user_ns, struct inode *inode,
+ const char *name, void *value, size_t size)
{
void *buffer = NULL;
ssize_t len;
if (!value || !size) {
- len = security_inode_getsecurity(inode, name, &buffer, false);
+ len = security_inode_getsecurity(user_ns, inode, name, &buffer, false);
goto out_noalloc;
}
- len = security_inode_getsecurity(inode, name, &buffer, true);
+ len = security_inode_getsecurity(user_ns, inode, name, &buffer, true);
if (len < 0)
return len;
if (size < len) {
@@ -399,7 +399,7 @@ vfs_getxattr(struct user_namespace *user_ns, struct dentry *dentry,
if (!strncmp(name, XATTR_SECURITY_PREFIX,
XATTR_SECURITY_PREFIX_LEN)) {
const char *suffix = name + XATTR_SECURITY_PREFIX_LEN;
- int ret = xattr_getsecurity(inode, suffix, value, size);
+ int ret = xattr_getsecurity(user_ns, inode, suffix, value, size);
/*
* Only overwrite the return value if a security module
* is actually active.
@@ -468,7 +468,7 @@ __vfs_removexattr_locked(struct user_namespace *user_ns, struct dentry *dentry,
if (error)
return error;
- error = security_inode_removexattr(dentry, name);
+ error = security_inode_removexattr(user_ns, dentry, name);
if (error)
goto out;
diff --git a/include/linux/capability.h b/include/linux/capability.h
index 0d54ca8abaed..92cd727677c4 100644
--- a/include/linux/capability.h
+++ b/include/linux/capability.h
@@ -271,7 +271,9 @@ static inline bool checkpoint_restore_ns_capable(struct user_namespace *ns)
}
/* audit system wants to get cap info from files as well */
-extern int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps);
+extern int get_vfs_caps_from_disk(struct user_namespace *user_ns,
+ const struct dentry *dentry,
+ struct cpu_vfs_cap_data *cpu_caps);
extern int cap_convert_nscap(struct user_namespace *user_ns,
struct dentry *dentry, void **ivalue, size_t size);
diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h
index 32a940117e7a..ae3dd00f6ffb 100644
--- a/include/linux/lsm_hook_defs.h
+++ b/include/linux/lsm_hook_defs.h
@@ -133,17 +133,20 @@ LSM_HOOK(int, 0, inode_follow_link, struct dentry *dentry, struct inode *inode,
LSM_HOOK(int, 0, inode_permission, struct inode *inode, int mask)
LSM_HOOK(int, 0, inode_setattr, struct dentry *dentry, struct iattr *attr)
LSM_HOOK(int, 0, inode_getattr, const struct path *path)
-LSM_HOOK(int, 0, inode_setxattr, struct dentry *dentry, const char *name,
- const void *value, size_t size, int flags)
+LSM_HOOK(int, 0, inode_setxattr, struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name, const void *value,
+ size_t size, int flags)
LSM_HOOK(void, LSM_RET_VOID, inode_post_setxattr, struct dentry *dentry,
const char *name, const void *value, size_t size, int flags)
LSM_HOOK(int, 0, inode_getxattr, struct dentry *dentry, const char *name)
LSM_HOOK(int, 0, inode_listxattr, struct dentry *dentry)
-LSM_HOOK(int, 0, inode_removexattr, struct dentry *dentry, const char *name)
+LSM_HOOK(int, 0, inode_removexattr, struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name)
LSM_HOOK(int, 0, inode_need_killpriv, struct dentry *dentry)
-LSM_HOOK(int, 0, inode_killpriv, struct dentry *dentry)
-LSM_HOOK(int, -EOPNOTSUPP, inode_getsecurity, struct inode *inode,
- const char *name, void **buffer, bool alloc)
+LSM_HOOK(int, 0, inode_killpriv, struct user_namespace *user_ns,
+ struct dentry *dentry)
+LSM_HOOK(int, -EOPNOTSUPP, inode_getsecurity, struct user_namespace *user_ns,
+ struct inode *inode, const char *name, void **buffer, bool alloc)
LSM_HOOK(int, -EOPNOTSUPP, inode_setsecurity, struct inode *inode,
const char *name, const void *value, size_t size, int flags)
LSM_HOOK(int, 0, inode_listsecurity, struct inode *inode, char *buffer,
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index c503f7ab8afb..465c9c308922 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -444,6 +444,7 @@
* @inode_killpriv:
* The setuid bit is being removed. Remove similar security labels.
* Called with the dentry->d_inode->i_mutex held.
+ * @user_ns the user namespace of the mount.
* @dentry is the dentry being changed.
* Return 0 on success. If error is returned, then the operation
* causing setuid bit removal is failed.
diff --git a/include/linux/security.h b/include/linux/security.h
index bc2725491560..b676a0816ae7 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -146,10 +146,13 @@ extern int cap_capset(struct cred *new, const struct cred *old,
extern int cap_bprm_creds_from_file(struct linux_binprm *bprm, struct file *file);
extern int cap_inode_setxattr(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags);
-extern int cap_inode_removexattr(struct dentry *dentry, const char *name);
+extern int cap_inode_removexattr(struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name);
extern int cap_inode_need_killpriv(struct dentry *dentry);
-extern int cap_inode_killpriv(struct dentry *dentry);
-extern int cap_inode_getsecurity(struct inode *inode, const char *name,
+extern int cap_inode_killpriv(struct user_namespace *user_ns,
+ struct dentry *dentry);
+extern int cap_inode_getsecurity(struct user_namespace *user_ns,
+ struct inode *inode, const char *name,
void **buffer, bool alloc);
extern int cap_mmap_addr(unsigned long addr);
extern int cap_mmap_file(struct file *file, unsigned long reqprot,
@@ -344,16 +347,21 @@ int security_inode_follow_link(struct dentry *dentry, struct inode *inode,
int security_inode_permission(struct inode *inode, int mask);
int security_inode_setattr(struct dentry *dentry, struct iattr *attr);
int security_inode_getattr(const struct path *path);
-int security_inode_setxattr(struct dentry *dentry, const char *name,
+int security_inode_setxattr(struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name,
const void *value, size_t size, int flags);
void security_inode_post_setxattr(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags);
int security_inode_getxattr(struct dentry *dentry, const char *name);
int security_inode_listxattr(struct dentry *dentry);
-int security_inode_removexattr(struct dentry *dentry, const char *name);
+int security_inode_removexattr(struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name);
int security_inode_need_killpriv(struct dentry *dentry);
-int security_inode_killpriv(struct dentry *dentry);
-int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc);
+int security_inode_killpriv(struct user_namespace *user_ns,
+ struct dentry *dentry);
+int security_inode_getsecurity(struct user_namespace *user_ns,
+ struct inode *inode, const char *name,
+ void **buffer, bool alloc);
int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags);
int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size);
void security_inode_getsecid(struct inode *inode, u32 *secid);
@@ -830,8 +838,9 @@ static inline int security_inode_getattr(const struct path *path)
return 0;
}
-static inline int security_inode_setxattr(struct dentry *dentry,
- const char *name, const void *value, size_t size, int flags)
+static inline int security_inode_setxattr(struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name, const void *value,
+ size_t size, int flags)
{
return cap_inode_setxattr(dentry, name, value, size, flags);
}
@@ -851,10 +860,11 @@ static inline int security_inode_listxattr(struct dentry *dentry)
return 0;
}
-static inline int security_inode_removexattr(struct dentry *dentry,
- const char *name)
+static inline int security_inode_removexattr(struct user_namespace *user_ns,
+ struct dentry *dentry,
+ const char *name)
{
- return cap_inode_removexattr(dentry, name);
+ return cap_inode_removexattr(user_ns, dentry, name);
}
static inline int security_inode_need_killpriv(struct dentry *dentry)
@@ -862,12 +872,16 @@ static inline int security_inode_need_killpriv(struct dentry *dentry)
return cap_inode_need_killpriv(dentry);
}
-static inline int security_inode_killpriv(struct dentry *dentry)
+static inline int security_inode_killpriv(struct user_namespace *user_ns,
+ struct dentry *dentry)
{
- return cap_inode_killpriv(dentry);
+ return cap_inode_killpriv(user_ns, dentry);
}
-static inline int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
+static inline int security_inode_getsecurity(struct user_namespace *user_ns,
+ struct inode *inode,
+ const char *name, void **buffer,
+ bool alloc)
{
return -EOPNOTSUPP;
}
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 8dba8f0983b5..383dcc1a54a4 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1944,7 +1944,7 @@ static inline int audit_copy_fcaps(struct audit_names *name,
if (!dentry)
return 0;
- rc = get_vfs_caps_from_disk(dentry, &caps);
+ rc = get_vfs_caps_from_disk(&init_user_ns, dentry, &caps);
if (rc)
return rc;
@@ -2495,7 +2495,8 @@ int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
ax->d.next = context->aux;
context->aux = (void *)ax;
- get_vfs_caps_from_disk(bprm->file->f_path.dentry, &vcaps);
+ get_vfs_caps_from_disk(&init_user_ns,
+ bprm->file->f_path.dentry, &vcaps);
ax->fcap.permitted = vcaps.permitted;
ax->fcap.inheritable = vcaps.inheritable;
diff --git a/security/commoncap.c b/security/commoncap.c
index 873820091b07..5071674f67b3 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -303,17 +303,18 @@ int cap_inode_need_killpriv(struct dentry *dentry)
/**
* cap_inode_killpriv - Erase the security markings on an inode
+ * @user_ns: The user namespace of the mount
* @dentry: The inode/dentry to alter
*
* Erase the privilege-enhancing security markings on an inode.
*
* Returns 0 if successful, -ve on error.
*/
-int cap_inode_killpriv(struct dentry *dentry)
+int cap_inode_killpriv(struct user_namespace *user_ns, struct dentry *dentry)
{
int error;
- error = __vfs_removexattr(&init_user_ns, dentry, XATTR_NAME_CAPS);
+ error = __vfs_removexattr(user_ns, dentry, XATTR_NAME_CAPS);
if (error == -EOPNOTSUPP)
error = 0;
return error;
@@ -366,8 +367,8 @@ static bool is_v3header(size_t size, const struct vfs_cap_data *cap)
* by the integrity subsystem, which really wants the unconverted values -
* so that's good.
*/
-int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer,
- bool alloc)
+int cap_inode_getsecurity(struct user_namespace *user_ns, struct inode *inode,
+ const char *name, void **buffer, bool alloc)
{
int size, ret;
kuid_t kroot;
@@ -386,8 +387,8 @@ int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer,
return -EINVAL;
size = sizeof(struct vfs_ns_cap_data);
- ret = (int)vfs_getxattr_alloc(&init_user_ns, dentry, XATTR_NAME_CAPS,
- &tmpbuf, size, GFP_NOFS);
+ ret = (int)vfs_getxattr_alloc(user_ns, dentry, XATTR_NAME_CAPS, &tmpbuf,
+ size, GFP_NOFS);
dput(dentry);
if (ret < 0)
@@ -412,6 +413,9 @@ int cap_inode_getsecurity(struct inode *inode, const char *name, void **buffer,
root = le32_to_cpu(nscap->rootid);
kroot = make_kuid(fs_ns, root);
+ /* If this is an idmapped mount shift the kuid. */
+ kroot = kuid_into_mnt(user_ns, kroot);
+
/* If the root kuid maps to a valid uid in current ns, then return
* this as a nscap. */
mappedroot = from_kuid(current_user_ns(), kroot);
@@ -573,7 +577,9 @@ static inline int bprm_caps_from_vfs_caps(struct cpu_vfs_cap_data *caps,
/*
* Extract the on-exec-apply capability sets for an executable file.
*/
-int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps)
+int get_vfs_caps_from_disk(struct user_namespace *user_ns,
+ const struct dentry *dentry,
+ struct cpu_vfs_cap_data *cpu_caps)
{
struct inode *inode = d_backing_inode(dentry);
__u32 magic_etc;
@@ -629,6 +635,7 @@ int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data
/* Limit the caps to the mounter of the filesystem
* or the more limited uid specified in the xattr.
*/
+ rootkuid = kuid_into_mnt(user_ns, rootkuid);
if (!rootid_owns_currentns(rootkuid))
return -ENODATA;
@@ -674,7 +681,7 @@ static int get_file_caps(struct linux_binprm *bprm, struct file *file,
if (!current_in_userns(file->f_path.mnt->mnt_sb->s_user_ns))
return 0;
- rc = get_vfs_caps_from_disk(file->f_path.dentry, &vcaps);
+ rc = get_vfs_caps_from_disk(mnt_user_ns(file->f_path.mnt), file->f_path.dentry, &vcaps);
if (rc < 0) {
if (rc == -EINVAL)
printk(KERN_NOTICE "Invalid argument reading file caps for %s\n",
@@ -939,6 +946,7 @@ int cap_inode_setxattr(struct dentry *dentry, const char *name,
/**
* cap_inode_removexattr - Determine whether an xattr may be removed
+ * @user_ns: The user namespace of the vfsmount
* @dentry: The inode/dentry being altered
* @name: The name of the xattr to be changed
*
@@ -948,7 +956,8 @@ int cap_inode_setxattr(struct dentry *dentry, const char *name,
* This is used to make sure security xattrs don't get removed by those who
* aren't privileged to remove them.
*/
-int cap_inode_removexattr(struct dentry *dentry, const char *name)
+int cap_inode_removexattr(struct user_namespace *mnt_user_ns,
+ struct dentry *dentry, const char *name)
{
struct user_namespace *user_ns = dentry->d_sb->s_user_ns;
@@ -962,8 +971,7 @@ int cap_inode_removexattr(struct dentry *dentry, const char *name)
struct inode *inode = d_backing_inode(dentry);
if (!inode)
return -EINVAL;
- if (!capable_wrt_inode_uidgid(&init_user_ns, inode,
- CAP_SETFCAP))
+ if (!capable_wrt_inode_uidgid(mnt_user_ns, inode, CAP_SETFCAP))
return -EPERM;
return 0;
}
diff --git a/security/security.c b/security/security.c
index a28045dc9e7f..942ae47b6b86 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1279,7 +1279,8 @@ int security_inode_getattr(const struct path *path)
return call_int_hook(inode_getattr, 0, path);
}
-int security_inode_setxattr(struct dentry *dentry, const char *name,
+int security_inode_setxattr(struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
int ret;
@@ -1290,8 +1291,8 @@ int security_inode_setxattr(struct dentry *dentry, const char *name,
* SELinux and Smack integrate the cap call,
* so assume that all LSMs supplying this call do so.
*/
- ret = call_int_hook(inode_setxattr, 1, dentry, name, value, size,
- flags);
+ ret = call_int_hook(inode_setxattr, 1, user_ns, dentry, name, value,
+ size, flags);
if (ret == 1)
ret = cap_inode_setxattr(dentry, name, value, size, flags);
@@ -1326,7 +1327,8 @@ int security_inode_listxattr(struct dentry *dentry)
return call_int_hook(inode_listxattr, 0, dentry);
}
-int security_inode_removexattr(struct dentry *dentry, const char *name)
+int security_inode_removexattr(struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name)
{
int ret;
@@ -1336,9 +1338,9 @@ int security_inode_removexattr(struct dentry *dentry, const char *name)
* SELinux and Smack integrate the cap call,
* so assume that all LSMs supplying this call do so.
*/
- ret = call_int_hook(inode_removexattr, 1, dentry, name);
+ ret = call_int_hook(inode_removexattr, 1, user_ns, dentry, name);
if (ret == 1)
- ret = cap_inode_removexattr(dentry, name);
+ ret = cap_inode_removexattr(user_ns, dentry, name);
if (ret)
return ret;
ret = ima_inode_removexattr(dentry, name);
@@ -1352,12 +1354,15 @@ int security_inode_need_killpriv(struct dentry *dentry)
return call_int_hook(inode_need_killpriv, 0, dentry);
}
-int security_inode_killpriv(struct dentry *dentry)
+int security_inode_killpriv(struct user_namespace *user_ns,
+ struct dentry *dentry)
{
- return call_int_hook(inode_killpriv, 0, dentry);
+ return call_int_hook(inode_killpriv, 0, user_ns, dentry);
}
-int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
+int security_inode_getsecurity(struct user_namespace *user_ns,
+ struct inode *inode, const char *name,
+ void **buffer, bool alloc)
{
struct security_hook_list *hp;
int rc;
@@ -1368,7 +1373,7 @@ int security_inode_getsecurity(struct inode *inode, const char *name, void **buf
* Only one module will provide an attribute with a given name.
*/
hlist_for_each_entry(hp, &security_hook_heads.inode_getsecurity, list) {
- rc = hp->hook.inode_getsecurity(inode, name, buffer, alloc);
+ rc = hp->hook.inode_getsecurity(user_ns, inode, name, buffer, alloc);
if (rc != LSM_RET_DEFAULT(inode_getsecurity))
return rc;
}
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 3f42950feed0..35066d41fe9f 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3112,7 +3112,8 @@ static bool has_cap_mac_admin(bool audit)
return true;
}
-static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
+static int selinux_inode_setxattr(struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
struct inode *inode = d_backing_inode(dentry);
@@ -3133,13 +3134,13 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
}
if (!selinux_initialized(&selinux_state))
- return (inode_owner_or_capable(&init_user_ns, inode) ? 0 : -EPERM);
+ return (inode_owner_or_capable(user_ns, inode) ? 0 : -EPERM);
sbsec = inode->i_sb->s_security;
if (!(sbsec->flags & SBLABEL_MNT))
return -EOPNOTSUPP;
- if (!inode_owner_or_capable(&init_user_ns, inode))
+ if (!inode_owner_or_capable(user_ns, inode))
return -EPERM;
ad.type = LSM_AUDIT_DATA_DENTRY;
@@ -3260,10 +3261,11 @@ static int selinux_inode_listxattr(struct dentry *dentry)
return dentry_has_perm(cred, dentry, FILE__GETATTR);
}
-static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
+static int selinux_inode_removexattr(struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name)
{
if (strcmp(name, XATTR_NAME_SELINUX)) {
- int rc = cap_inode_removexattr(dentry, name);
+ int rc = cap_inode_removexattr(user_ns, dentry, name);
if (rc)
return rc;
@@ -3329,7 +3331,9 @@ static int selinux_path_notify(const struct path *path, u64 mask,
*
* Permission check is handled by selinux_inode_getxattr hook.
*/
-static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
+static int selinux_inode_getsecurity(struct user_namespace *user_ns,
+ struct inode *inode, const char *name,
+ void **buffer, bool alloc)
{
u32 size;
int error;
@@ -6524,8 +6528,8 @@ static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
{
int len = 0;
- len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
- ctx, true);
+ len = selinux_inode_getsecurity(&init_user_ns, inode,
+ XATTR_SELINUX_SUFFIX, ctx, true);
if (len < 0)
return len;
*ctxlen = len;
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 11003244b18b..fde9f124d5ee 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -1240,7 +1240,8 @@ static int smack_inode_getattr(const struct path *path)
*
* Returns 0 if access is permitted, an error code otherwise
*/
-static int smack_inode_setxattr(struct dentry *dentry, const char *name,
+static int smack_inode_setxattr(struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
struct smk_audit_info ad;
@@ -1362,7 +1363,8 @@ static int smack_inode_getxattr(struct dentry *dentry, const char *name)
*
* Returns 0 if access is permitted, an error code otherwise
*/
-static int smack_inode_removexattr(struct dentry *dentry, const char *name)
+static int smack_inode_removexattr(struct user_namespace *user_ns,
+ struct dentry *dentry, const char *name)
{
struct inode_smack *isp;
struct smk_audit_info ad;
@@ -1377,7 +1379,7 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name)
if (!smack_privileged(CAP_MAC_ADMIN))
rc = -EPERM;
} else
- rc = cap_inode_removexattr(dentry, name);
+ rc = cap_inode_removexattr(user_ns, dentry, name);
if (rc != 0)
return rc;
@@ -1420,9 +1422,9 @@ static int smack_inode_removexattr(struct dentry *dentry, const char *name)
*
* Returns the size of the attribute or an error code
*/
-static int smack_inode_getsecurity(struct inode *inode,
- const char *name, void **buffer,
- bool alloc)
+static int smack_inode_getsecurity(struct user_namespace *user_ns,
+ struct inode *inode, const char *name,
+ void **buffer, bool alloc)
{
struct socket_smack *ssp;
struct socket *sock;
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 15/38] stat: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (13 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 14/38] commoncap: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 16/38] namei: handle idmapped mounts in may_*() helpers Christian Brauner
` (21 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
The generic_fillattr() helper fills in the basic attributes associated with an
inode. Enable it to handle idmapped mounts. If the inode is accessed through an
idmapped mount we need to map it according to the mount's user namespace before
we store the uid and gid.
If the initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Don't pollute the vfs with additional helpers simply extend the existing
helpers with an additional argument and switch all callers.
/* v3 */
unchanged
---
fs/9p/vfs_inode.c | 4 ++--
fs/9p/vfs_inode_dotl.c | 4 ++--
fs/afs/inode.c | 2 +-
fs/btrfs/inode.c | 2 +-
fs/ceph/inode.c | 2 +-
fs/cifs/inode.c | 2 +-
fs/coda/inode.c | 2 +-
fs/ecryptfs/inode.c | 4 ++--
fs/erofs/inode.c | 2 +-
fs/exfat/file.c | 2 +-
fs/ext2/inode.c | 2 +-
fs/ext4/inode.c | 2 +-
fs/f2fs/file.c | 2 +-
fs/fat/file.c | 2 +-
fs/fuse/dir.c | 2 +-
fs/gfs2/inode.c | 2 +-
fs/hfsplus/inode.c | 2 +-
fs/kernfs/inode.c | 2 +-
fs/libfs.c | 4 ++--
fs/minix/inode.c | 2 +-
fs/nfs/inode.c | 2 +-
fs/nfs/namespace.c | 2 +-
fs/ocfs2/file.c | 2 +-
fs/orangefs/inode.c | 2 +-
fs/proc/base.c | 8 ++++----
fs/proc/generic.c | 2 +-
fs/proc/proc_net.c | 2 +-
fs/proc/proc_sysctl.c | 2 +-
fs/proc/root.c | 2 +-
fs/stat.c | 10 ++++++----
fs/sysv/itree.c | 2 +-
fs/ubifs/dir.c | 2 +-
fs/udf/symlink.c | 2 +-
fs/vboxsf/utils.c | 2 +-
include/linux/fs.h | 2 +-
mm/shmem.c | 2 +-
36 files changed, 48 insertions(+), 46 deletions(-)
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 404526499c94..0a5c022c1c70 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -1006,7 +1006,7 @@ v9fs_vfs_getattr(const struct path *path, struct kstat *stat,
p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
v9ses = v9fs_dentry2v9ses(dentry);
if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
- generic_fillattr(d_inode(dentry), stat);
+ generic_fillattr(&init_user_ns, d_inode(dentry), stat);
return 0;
}
fid = v9fs_fid_lookup(dentry);
@@ -1018,7 +1018,7 @@ v9fs_vfs_getattr(const struct path *path, struct kstat *stat,
return PTR_ERR(st);
v9fs_stat2inode(st, d_inode(dentry), dentry->d_sb, 0);
- generic_fillattr(d_inode(dentry), stat);
+ generic_fillattr(&init_user_ns, d_inode(dentry), stat);
p9stat_free(st);
kfree(st);
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 282ec5cb45dc..8f3c1daf72ba 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -466,7 +466,7 @@ v9fs_vfs_getattr_dotl(const struct path *path, struct kstat *stat,
p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
v9ses = v9fs_dentry2v9ses(dentry);
if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
- generic_fillattr(d_inode(dentry), stat);
+ generic_fillattr(&init_user_ns, d_inode(dentry), stat);
return 0;
}
fid = v9fs_fid_lookup(dentry);
@@ -482,7 +482,7 @@ v9fs_vfs_getattr_dotl(const struct path *path, struct kstat *stat,
return PTR_ERR(st);
v9fs_stat2inode_dotl(st, d_inode(dentry), 0);
- generic_fillattr(d_inode(dentry), stat);
+ generic_fillattr(&init_user_ns, d_inode(dentry), stat);
/* Change block size to what the server returned */
stat->blksize = st->st_blksize;
diff --git a/fs/afs/inode.c b/fs/afs/inode.c
index 0fe8844b4bee..17ecdee404eb 100644
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -737,7 +737,7 @@ int afs_getattr(const struct path *path, struct kstat *stat,
do {
read_seqbegin_or_lock(&vnode->cb_lock, &seq);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
if (test_bit(AFS_VNODE_SILLY_DELETED, &vnode->flags) &&
stat->nlink > 0)
stat->nlink -= 1;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index e6f4aed0d311..99b4fd66681d 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -8783,7 +8783,7 @@ static int btrfs_getattr(const struct path *path, struct kstat *stat,
STATX_ATTR_IMMUTABLE |
STATX_ATTR_NODUMP);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
stat->dev = BTRFS_I(inode)->root->anon_dev;
spin_lock(&BTRFS_I(inode)->lock);
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 19ec845ba5ec..decfa5e1ec4c 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -2380,7 +2380,7 @@ int ceph_getattr(const struct path *path, struct kstat *stat,
return err;
}
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
stat->ino = ceph_present_inode(inode);
/*
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 4d69b786e403..4fb3b6961096 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -2400,7 +2400,7 @@ int cifs_getattr(const struct path *path, struct kstat *stat,
return rc;
}
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
stat->blksize = cifs_sb->bsize;
stat->ino = CIFS_I(inode)->uniqueid;
diff --git a/fs/coda/inode.c b/fs/coda/inode.c
index b1c70e2b9b1e..4d113e191cb8 100644
--- a/fs/coda/inode.c
+++ b/fs/coda/inode.c
@@ -256,7 +256,7 @@ int coda_getattr(const struct path *path, struct kstat *stat,
{
int err = coda_revalidate_inode(d_inode(path->dentry));
if (!err)
- generic_fillattr(d_inode(path->dentry), stat);
+ generic_fillattr(&init_user_ns, d_inode(path->dentry), stat);
return err;
}
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index c35c2d2f3fe6..d98448c75051 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -975,7 +975,7 @@ static int ecryptfs_getattr_link(const struct path *path, struct kstat *stat,
mount_crypt_stat = &ecryptfs_superblock_to_private(
dentry->d_sb)->mount_crypt_stat;
- generic_fillattr(d_inode(dentry), stat);
+ generic_fillattr(&init_user_ns, d_inode(dentry), stat);
if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
char *target;
size_t targetsiz;
@@ -1003,7 +1003,7 @@ static int ecryptfs_getattr(const struct path *path, struct kstat *stat,
if (!rc) {
fsstack_copy_attr_all(d_inode(dentry),
ecryptfs_inode_to_lower(d_inode(dentry)));
- generic_fillattr(d_inode(dentry), stat);
+ generic_fillattr(&init_user_ns, d_inode(dentry), stat);
stat->blocks = lower_stat.blocks;
}
return rc;
diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index 3e21c0e8adae..083818063ac6 100644
--- a/fs/erofs/inode.c
+++ b/fs/erofs/inode.c
@@ -343,7 +343,7 @@ int erofs_getattr(const struct path *path, struct kstat *stat,
stat->attributes_mask |= (STATX_ATTR_COMPRESSED |
STATX_ATTR_IMMUTABLE);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
return 0;
}
diff --git a/fs/exfat/file.c b/fs/exfat/file.c
index ace35aa8e64b..e9705b3295d3 100644
--- a/fs/exfat/file.c
+++ b/fs/exfat/file.c
@@ -273,7 +273,7 @@ int exfat_getattr(const struct path *path, struct kstat *stat,
struct inode *inode = d_backing_inode(path->dentry);
struct exfat_inode_info *ei = EXFAT_I(inode);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
exfat_truncate_atime(&stat->atime);
stat->result_mask |= STATX_BTIME;
stat->btime.tv_sec = ei->i_crtime.tv_sec;
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 5ff1e5e3c0fe..7fcda76094ff 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -1659,7 +1659,7 @@ int ext2_getattr(const struct path *path, struct kstat *stat,
STATX_ATTR_IMMUTABLE |
STATX_ATTR_NODUMP);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
return 0;
}
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index f0487795afd1..d992fef2e7c2 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5558,7 +5558,7 @@ int ext4_getattr(const struct path *path, struct kstat *stat,
STATX_ATTR_NODUMP |
STATX_ATTR_VERITY);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
return 0;
}
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 3633a558ddcc..34f6522f5828 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -814,7 +814,7 @@ int f2fs_getattr(const struct path *path, struct kstat *stat,
STATX_ATTR_NODUMP |
STATX_ATTR_VERITY);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
/* we need to show initial sectors used for inline_data/dentries */
if ((S_ISREG(inode->i_mode) && f2fs_has_inline_data(inode)) ||
diff --git a/fs/fat/file.c b/fs/fat/file.c
index 805b501467e9..f7e04f533d31 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -398,7 +398,7 @@ int fat_getattr(const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int flags)
{
struct inode *inode = d_inode(path->dentry);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
stat->blksize = MSDOS_SB(inode->i_sb)->cluster_size;
if (MSDOS_SB(inode->i_sb)->options.nfs == FAT_NFS_NOSTALE_RO) {
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index dc6e8cc565d2..0750755685cd 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -1064,7 +1064,7 @@ static int fuse_update_get_attr(struct inode *inode, struct file *file,
forget_all_cached_acls(inode);
err = fuse_do_getattr(inode, stat, file);
} else if (stat) {
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
stat->mode = fi->orig_i_mode;
stat->ino = fi->orig_ino;
}
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index a29b66116c01..f1841667bcd9 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -2048,7 +2048,7 @@ static int gfs2_getattr(const struct path *path, struct kstat *stat,
STATX_ATTR_IMMUTABLE |
STATX_ATTR_NODUMP);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
if (gfs2_holder_initialized(&gh))
gfs2_glock_dq_uninit(&gh);
diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c
index a2789730f451..a34f37a53dcd 100644
--- a/fs/hfsplus/inode.c
+++ b/fs/hfsplus/inode.c
@@ -286,7 +286,7 @@ int hfsplus_getattr(const struct path *path, struct kstat *stat,
stat->attributes_mask |= STATX_ATTR_APPEND | STATX_ATTR_IMMUTABLE |
STATX_ATTR_NODUMP;
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
return 0;
}
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index 74ee0ffcfe71..062593491bbe 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -193,7 +193,7 @@ int kernfs_iop_getattr(const struct path *path, struct kstat *stat,
kernfs_refresh_inode(kn, inode);
mutex_unlock(&kernfs_mutex);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
return 0;
}
diff --git a/fs/libfs.c b/fs/libfs.c
index f50446576b10..6aa8bead838f 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -31,7 +31,7 @@ int simple_getattr(const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int query_flags)
{
struct inode *inode = d_inode(path->dentry);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
stat->blocks = inode->i_mapping->nrpages << (PAGE_SHIFT - 9);
return 0;
}
@@ -1302,7 +1302,7 @@ static int empty_dir_getattr(const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int query_flags)
{
struct inode *inode = d_inode(path->dentry);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
return 0;
}
diff --git a/fs/minix/inode.c b/fs/minix/inode.c
index 34f546404aa1..91c81d2fc90d 100644
--- a/fs/minix/inode.c
+++ b/fs/minix/inode.c
@@ -658,7 +658,7 @@ int minix_getattr(const struct path *path, struct kstat *stat,
struct super_block *sb = path->dentry->d_sb;
struct inode *inode = d_inode(path->dentry);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
if (INODE_VERSION(inode) == MINIX_V1)
stat->blocks = (BLOCK_SIZE / 512) * V1_minix_blocks(stat->size, sb);
else
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index aa6493905bbe..8d74974d7992 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -858,7 +858,7 @@ int nfs_getattr(const struct path *path, struct kstat *stat,
/* Only return attributes that were revalidated. */
stat->result_mask &= request_mask;
out_no_update:
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
if (S_ISDIR(inode->i_mode))
stat->blksize = NFS_SERVER(inode)->dtsize;
diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index 2bcbe38afe2e..55fc711e368b 100644
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -213,7 +213,7 @@ nfs_namespace_getattr(const struct path *path, struct kstat *stat,
{
if (NFS_FH(d_inode(path->dentry))->size != 0)
return nfs_getattr(path, stat, request_mask, query_flags);
- generic_fillattr(d_inode(path->dentry), stat);
+ generic_fillattr(&init_user_ns, d_inode(path->dentry), stat);
return 0;
}
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index cabf355b148f..a070d4c9b6ed 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1313,7 +1313,7 @@ int ocfs2_getattr(const struct path *path, struct kstat *stat,
goto bail;
}
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
/*
* If there is inline data in the inode, the inode will normally not
* have data blocks allocated (it may have an external xattr block).
diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c
index 563fe9ab8eb2..b94032f77e61 100644
--- a/fs/orangefs/inode.c
+++ b/fs/orangefs/inode.c
@@ -903,7 +903,7 @@ int orangefs_getattr(const struct path *path, struct kstat *stat,
ret = orangefs_inode_getattr(inode,
request_mask & STATX_SIZE ? ORANGEFS_GETATTR_SIZE : 0);
if (ret == 0) {
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
/* override block size reported to stat */
if (!(request_mask & STATX_SIZE))
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 266b54b75c4c..c711d6fb3051 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1934,7 +1934,7 @@ int pid_getattr(const struct path *path, struct kstat *stat,
struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb);
struct task_struct *task;
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
stat->uid = GLOBAL_ROOT_UID;
stat->gid = GLOBAL_ROOT_GID;
@@ -2620,7 +2620,7 @@ static struct dentry *proc_pident_instantiate(struct dentry *dentry,
return d_splice_alias(inode, dentry);
}
-static struct dentry *proc_pident_lookup(struct inode *dir,
+static struct dentry *proc_pident_lookup(struct inode *dir,
struct dentry *dentry,
const struct pid_entry *p,
const struct pid_entry *end)
@@ -2820,7 +2820,7 @@ static const struct pid_entry attr_dir_stuff[] = {
static int proc_attr_dir_readdir(struct file *file, struct dir_context *ctx)
{
- return proc_pident_readdir(file, ctx,
+ return proc_pident_readdir(file, ctx,
attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
}
@@ -3797,7 +3797,7 @@ static int proc_task_getattr(const struct path *path, struct kstat *stat,
{
struct inode *inode = d_inode(path->dentry);
struct task_struct *p = get_proc_task(inode);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
if (p) {
stat->nlink += get_nr_threads(p);
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 896f2ebde75c..5c6345c68fc5 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -145,7 +145,7 @@ static int proc_getattr(const struct path *path, struct kstat *stat,
}
}
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
return 0;
}
diff --git a/fs/proc/proc_net.c b/fs/proc/proc_net.c
index ed8a6306990c..bc555b7da6dc 100644
--- a/fs/proc/proc_net.c
+++ b/fs/proc/proc_net.c
@@ -313,7 +313,7 @@ static int proc_tgid_net_getattr(const struct path *path, struct kstat *stat,
net = get_proc_task_net(inode);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
if (net != NULL) {
stat->nlink = net->proc_net->nlink;
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index ec67dbc1f705..87c828348140 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -840,7 +840,7 @@ static int proc_sys_getattr(const struct path *path, struct kstat *stat,
if (IS_ERR(head))
return PTR_ERR(head);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
if (table)
stat->mode = (stat->mode & S_IFMT) | table->mode;
diff --git a/fs/proc/root.c b/fs/proc/root.c
index 5e444d4f9717..244e4b6f15ef 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -311,7 +311,7 @@ void __init proc_root_init(void)
static int proc_root_getattr(const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int query_flags)
{
- generic_fillattr(d_inode(path->dentry), stat);
+ generic_fillattr(&init_user_ns, d_inode(path->dentry), stat);
stat->nlink = proc_root.nlink + nr_processes();
return 0;
}
diff --git a/fs/stat.c b/fs/stat.c
index dacecdda2e79..868e39e101bc 100644
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -26,6 +26,7 @@
/**
* generic_fillattr - Fill in the basic attributes from the inode struct
+ * @user_ns: the user namespace from which we access this inode
* @inode: Inode to use as the source
* @stat: Where to fill in the attributes
*
@@ -33,14 +34,15 @@
* found on the VFS inode structure. This is the default if no getattr inode
* operation is supplied.
*/
-void generic_fillattr(struct inode *inode, struct kstat *stat)
+void generic_fillattr(struct user_namespace *mnt_user_ns, struct inode *inode,
+ struct kstat *stat)
{
stat->dev = inode->i_sb->s_dev;
stat->ino = inode->i_ino;
stat->mode = inode->i_mode;
stat->nlink = inode->i_nlink;
- stat->uid = inode->i_uid;
- stat->gid = inode->i_gid;
+ stat->uid = i_uid_into_mnt(mnt_user_ns, inode);
+ stat->gid = i_gid_into_mnt(mnt_user_ns, inode);
stat->rdev = inode->i_rdev;
stat->size = i_size_read(inode);
stat->atime = inode->i_atime;
@@ -87,7 +89,7 @@ int vfs_getattr_nosec(const struct path *path, struct kstat *stat,
return inode->i_op->getattr(path, stat, request_mask,
query_flags);
- generic_fillattr(inode, stat);
+ generic_fillattr(mnt_user_ns(path->mnt), inode, stat);
return 0;
}
EXPORT_SYMBOL(vfs_getattr_nosec);
diff --git a/fs/sysv/itree.c b/fs/sysv/itree.c
index bcb67b0cabe7..83cffab6955f 100644
--- a/fs/sysv/itree.c
+++ b/fs/sysv/itree.c
@@ -445,7 +445,7 @@ int sysv_getattr(const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int flags)
{
struct super_block *s = path->dentry->d_sb;
- generic_fillattr(d_inode(path->dentry), stat);
+ generic_fillattr(&init_user_ns, d_inode(path->dentry), stat);
stat->blocks = (s->s_blocksize / 512) * sysv_nblocks(s, stat->size);
stat->blksize = s->s_blocksize;
return 0;
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index 1639331f9543..144422c39125 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -1579,7 +1579,7 @@ int ubifs_getattr(const struct path *path, struct kstat *stat,
STATX_ATTR_ENCRYPTED |
STATX_ATTR_IMMUTABLE);
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
stat->blksize = UBIFS_BLOCK_SIZE;
stat->size = ui->ui_size;
diff --git a/fs/udf/symlink.c b/fs/udf/symlink.c
index c973db239604..54a44d1f023c 100644
--- a/fs/udf/symlink.c
+++ b/fs/udf/symlink.c
@@ -159,7 +159,7 @@ static int udf_symlink_getattr(const struct path *path, struct kstat *stat,
struct inode *inode = d_backing_inode(dentry);
struct page *page;
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
page = read_mapping_page(inode->i_mapping, 0, NULL);
if (IS_ERR(page))
return PTR_ERR(page);
diff --git a/fs/vboxsf/utils.c b/fs/vboxsf/utils.c
index 018057546067..d2cd1c99f48e 100644
--- a/fs/vboxsf/utils.c
+++ b/fs/vboxsf/utils.c
@@ -233,7 +233,7 @@ int vboxsf_getattr(const struct path *path, struct kstat *kstat,
if (err)
return err;
- generic_fillattr(d_inode(dentry), kstat);
+ generic_fillattr(&init_user_ns, d_inode(dentry), kstat);
return 0;
}
diff --git a/include/linux/fs.h b/include/linux/fs.h
index ef6917e1ec75..696ad3e0df03 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3139,7 +3139,7 @@ extern int __page_symlink(struct inode *inode, const char *symname, int len,
extern int page_symlink(struct inode *inode, const char *symname, int len);
extern const struct inode_operations page_symlink_inode_operations;
extern void kfree_link(void *);
-extern void generic_fillattr(struct inode *, struct kstat *);
+extern void generic_fillattr(struct user_namespace *, struct inode *, struct kstat *);
extern int vfs_getattr_nosec(const struct path *, struct kstat *, u32, unsigned int);
extern int vfs_getattr(const struct path *, struct kstat *, u32, unsigned int);
void __inode_add_bytes(struct inode *inode, loff_t bytes);
diff --git a/mm/shmem.c b/mm/shmem.c
index 8fdf52576e06..7c317b0d06f0 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1072,7 +1072,7 @@ static int shmem_getattr(const struct path *path, struct kstat *stat,
shmem_recalc_inode(inode);
spin_unlock_irq(&info->lock);
}
- generic_fillattr(inode, stat);
+ generic_fillattr(&init_user_ns, inode, stat);
if (is_huge_enabled(sb_info))
stat->blksize = HPAGE_PMD_SIZE;
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 16/38] namei: handle idmapped mounts in may_*() helpers
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (14 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 15/38] stat: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 17/38] namei: introduce struct renamedata Christian Brauner
` (20 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
The may_follow_link(), may_linkat(), may_lookup(), may_open(), may_o_create(),
may_create_in_sticky(), may_delete(), and may_create() helpers determine
whether the caller is privileged enough to perform the associated operations.
Let them handle idmapped mounts by mappings the inode and fsids according to the
mount's user namespace. Afterwards the checks are identical to non-idmapped
inodes. If the initial user namespace is passed nothing changes so non-idmapped
mounts will see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
fs/btrfs/ioctl.c | 5 +-
fs/inode.c | 2 +-
fs/namei.c | 121 +++++++++++++++++++++++++++------------------
fs/xattr.c | 2 +-
include/linux/fs.h | 13 +++--
5 files changed, 86 insertions(+), 57 deletions(-)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index f5d3ebca4c5f..114bd15304f2 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -915,8 +915,9 @@ static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
return error;
if (IS_APPEND(dir))
return -EPERM;
- if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
- IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
+ if (check_sticky(&init_user_ns, dir, d_inode(victim)) ||
+ IS_APPEND(d_inode(victim)) || IS_IMMUTABLE(d_inode(victim)) ||
+ IS_SWAPFILE(d_inode(victim)))
return -EPERM;
if (isdir) {
if (!d_is_dir(victim))
diff --git a/fs/inode.c b/fs/inode.c
index 66d3f7397d86..75c64f003c45 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1797,7 +1797,7 @@ bool atime_needs_update(const struct path *path, struct inode *inode)
/* Atime updates will likely cause i_uid and i_gid to be written
* back improprely if their true value is unknown to the vfs.
*/
- if (HAS_UNMAPPED_ID(inode))
+ if (HAS_UNMAPPED_ID(mnt_user_ns(mnt), inode))
return false;
if (IS_NOATIME(inode))
diff --git a/fs/namei.c b/fs/namei.c
index 35952c28ee29..4dc842d1cd3a 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -465,7 +465,7 @@ int inode_permission(struct user_namespace *user_ns,
* written back improperly if their true value is unknown
* to the vfs.
*/
- if (HAS_UNMAPPED_ID(inode))
+ if (HAS_UNMAPPED_ID(user_ns, inode))
return -EACCES;
}
@@ -963,11 +963,16 @@ int sysctl_protected_regular __read_mostly;
*/
static inline int may_follow_link(struct nameidata *nd, const struct inode *inode)
{
+ struct user_namespace *user_ns;
+ kuid_t i_uid;
+
if (!sysctl_protected_symlinks)
return 0;
+ user_ns = mnt_user_ns(nd->path.mnt);
+ i_uid = i_uid_into_mnt(user_ns, inode);
/* Allowed if owner and follower match. */
- if (uid_eq(current_cred()->fsuid, inode->i_uid))
+ if (uid_eq(current_cred()->fsuid, i_uid))
return 0;
/* Allowed if parent directory not sticky and world-writable. */
@@ -975,7 +980,7 @@ static inline int may_follow_link(struct nameidata *nd, const struct inode *inod
return 0;
/* Allowed if parent directory and link owner match. */
- if (uid_valid(nd->dir_uid) && uid_eq(nd->dir_uid, inode->i_uid))
+ if (uid_valid(nd->dir_uid) && uid_eq(nd->dir_uid, i_uid))
return 0;
if (nd->flags & LOOKUP_RCU)
@@ -998,7 +1003,7 @@ static inline int may_follow_link(struct nameidata *nd, const struct inode *inod
*
* Otherwise returns true.
*/
-static bool safe_hardlink_source(struct inode *inode)
+static bool safe_hardlink_source(struct user_namespace *user_ns, struct inode *inode)
{
umode_t mode = inode->i_mode;
@@ -1015,7 +1020,7 @@ static bool safe_hardlink_source(struct inode *inode)
return false;
/* Hardlinking to unreadable or unwritable sources is dangerous. */
- if (inode_permission(&init_user_ns, inode, MAY_READ | MAY_WRITE))
+ if (inode_permission(user_ns, inode, MAY_READ | MAY_WRITE))
return false;
return true;
@@ -1036,9 +1041,12 @@ static bool safe_hardlink_source(struct inode *inode)
int may_linkat(struct path *link)
{
struct inode *inode = link->dentry->d_inode;
+ struct user_namespace *user_ns;
/* Inode writeback is not safe when the uid or gid are invalid. */
- if (!uid_valid(inode->i_uid) || !gid_valid(inode->i_gid))
+ user_ns = mnt_user_ns(link->mnt);
+ if (!uid_valid(i_uid_into_mnt(user_ns, inode)) ||
+ !gid_valid(i_gid_into_mnt(user_ns, inode)))
return -EOVERFLOW;
if (!sysctl_protected_hardlinks)
@@ -1047,7 +1055,8 @@ int may_linkat(struct path *link)
/* Source inode owner (or CAP_FOWNER) can hardlink all they like,
* otherwise, it must be a safe source.
*/
- if (safe_hardlink_source(inode) || inode_owner_or_capable(&init_user_ns, inode))
+ if (safe_hardlink_source(user_ns, inode) ||
+ inode_owner_or_capable(user_ns, inode))
return 0;
audit_log_path_denied(AUDIT_ANOM_LINK, "linkat");
@@ -1075,14 +1084,18 @@ int may_linkat(struct path *link)
*
* Returns 0 if the open is allowed, -ve on error.
*/
-static int may_create_in_sticky(umode_t dir_mode, kuid_t dir_uid,
- struct inode * const inode)
+static int may_create_in_sticky(struct nameidata *nd, struct inode *const inode)
{
+ struct user_namespace *user_ns;
+ umode_t dir_mode = nd->dir_mode;
+ kuid_t dir_uid = nd->dir_uid;
+
+ user_ns = mnt_user_ns(nd->path.mnt);
if ((!sysctl_protected_fifos && S_ISFIFO(inode->i_mode)) ||
(!sysctl_protected_regular && S_ISREG(inode->i_mode)) ||
likely(!(dir_mode & S_ISVTX)) ||
- uid_eq(inode->i_uid, dir_uid) ||
- uid_eq(current_fsuid(), inode->i_uid))
+ uid_eq(i_uid_into_mnt(user_ns, inode), dir_uid) ||
+ uid_eq(current_fsuid(), i_uid_into_mnt(user_ns, inode)))
return 0;
if (likely(dir_mode & 0002) ||
@@ -1574,15 +1587,16 @@ static struct dentry *lookup_slow(const struct qstr *name,
static inline int may_lookup(struct nameidata *nd)
{
+ struct user_namespace *user_ns = mnt_user_ns(nd->path.mnt);
+
if (nd->flags & LOOKUP_RCU) {
- int err = inode_permission(&init_user_ns, nd->inode,
- MAY_EXEC | MAY_NOT_BLOCK);
+ int err = inode_permission(user_ns, nd->inode, MAY_EXEC|MAY_NOT_BLOCK);
if (err != -ECHILD)
return err;
if (unlazy_walk(nd))
return -ECHILD;
}
- return inode_permission(&init_user_ns, nd->inode, MAY_EXEC);
+ return inode_permission(user_ns, nd->inode, MAY_EXEC);
}
static int reserve_stack(struct nameidata *nd, struct path *link, unsigned seq)
@@ -2181,7 +2195,10 @@ static int link_path_walk(const char *name, struct nameidata *nd)
OK:
/* pathname or trailing symlink, done */
if (!depth) {
- nd->dir_uid = nd->inode->i_uid;
+ struct user_namespace *user_ns;
+
+ user_ns = mnt_user_ns(nd->path.mnt);
+ nd->dir_uid = i_uid_into_mnt(user_ns, nd->inode);
nd->dir_mode = nd->inode->i_mode;
nd->flags &= ~LOOKUP_PARENT;
return 0;
@@ -2659,15 +2676,16 @@ int user_path_at_empty(int dfd, const char __user *name, unsigned flags,
}
EXPORT_SYMBOL(user_path_at_empty);
-int __check_sticky(struct inode *dir, struct inode *inode)
+int __check_sticky(struct user_namespace *user_ns, struct inode *dir,
+ struct inode *inode)
{
kuid_t fsuid = current_fsuid();
- if (uid_eq(inode->i_uid, fsuid))
+ if (uid_eq(i_uid_into_mnt(user_ns, inode), fsuid))
return 0;
- if (uid_eq(dir->i_uid, fsuid))
+ if (uid_eq(i_uid_into_mnt(user_ns, dir), fsuid))
return 0;
- return !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FOWNER);
+ return !capable_wrt_inode_uidgid(user_ns, inode, CAP_FOWNER);
}
EXPORT_SYMBOL(__check_sticky);
@@ -2691,7 +2709,7 @@ EXPORT_SYMBOL(__check_sticky);
* 11. We don't allow removal of NFS sillyrenamed files; it's handled by
* nfs_async_unlink().
*/
-static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
+static int may_delete(struct user_namespace *user_ns, struct inode *dir, struct dentry *victim, bool isdir)
{
struct inode *inode = d_backing_inode(victim);
int error;
@@ -2703,19 +2721,21 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
BUG_ON(victim->d_parent->d_inode != dir);
/* Inode writeback is not safe when the uid or gid are invalid. */
- if (!uid_valid(inode->i_uid) || !gid_valid(inode->i_gid))
+ if (!uid_valid(i_uid_into_mnt(user_ns, inode)) ||
+ !gid_valid(i_gid_into_mnt(user_ns, inode)))
return -EOVERFLOW;
audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
- error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
+ error = inode_permission(user_ns, dir, MAY_WRITE | MAY_EXEC);
if (error)
return error;
if (IS_APPEND(dir))
return -EPERM;
- if (check_sticky(dir, inode) || IS_APPEND(inode) ||
- IS_IMMUTABLE(inode) || IS_SWAPFILE(inode) || HAS_UNMAPPED_ID(inode))
+ if (check_sticky(user_ns, dir, inode) || IS_APPEND(inode) ||
+ IS_IMMUTABLE(inode) || IS_SWAPFILE(inode) ||
+ HAS_UNMAPPED_ID(user_ns, inode))
return -EPERM;
if (isdir) {
if (!d_is_dir(victim))
@@ -2740,7 +2760,8 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
* 4. We should have write and exec permissions on dir
* 5. We can't do it if dir is immutable (done in permission())
*/
-static inline int may_create(struct inode *dir, struct dentry *child)
+static inline int may_create(struct user_namespace *user_ns, struct inode *dir,
+ struct dentry *child)
{
struct user_namespace *s_user_ns;
audit_inode_child(dir, child, AUDIT_TYPE_CHILD_CREATE);
@@ -2749,10 +2770,10 @@ static inline int may_create(struct inode *dir, struct dentry *child)
if (IS_DEADDIR(dir))
return -ENOENT;
s_user_ns = dir->i_sb->s_user_ns;
- if (!kuid_has_mapping(s_user_ns, current_fsuid()) ||
- !kgid_has_mapping(s_user_ns, current_fsgid()))
+ if (!kuid_has_mapping(s_user_ns, fsuid_into_mnt(user_ns)) ||
+ !kgid_has_mapping(s_user_ns, fsgid_into_mnt(user_ns)))
return -EOVERFLOW;
- return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
+ return inode_permission(user_ns, dir, MAY_WRITE | MAY_EXEC);
}
/*
@@ -2802,7 +2823,7 @@ EXPORT_SYMBOL(unlock_rename);
int vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
bool want_excl)
{
- int error = may_create(dir, dentry);
+ int error = may_create(&init_user_ns, dir, dentry);
if (error)
return error;
@@ -2825,7 +2846,7 @@ int vfs_mkobj(struct dentry *dentry, umode_t mode,
void *arg)
{
struct inode *dir = dentry->d_parent->d_inode;
- int error = may_create(dir, dentry);
+ int error = may_create(&init_user_ns, dir, dentry);
if (error)
return error;
@@ -2849,6 +2870,7 @@ bool may_open_dev(const struct path *path)
static int may_open(const struct path *path, int acc_mode, int flag)
{
+ struct user_namespace *user_ns;
struct dentry *dentry = path->dentry;
struct inode *inode = dentry->d_inode;
int error;
@@ -2882,7 +2904,8 @@ static int may_open(const struct path *path, int acc_mode, int flag)
break;
}
- error = inode_permission(&init_user_ns, inode, MAY_OPEN | acc_mode);
+ user_ns = mnt_user_ns(path->mnt);
+ error = inode_permission(user_ns, inode, MAY_OPEN | acc_mode);
if (error)
return error;
@@ -2897,7 +2920,7 @@ static int may_open(const struct path *path, int acc_mode, int flag)
}
/* O_NOATIME can only be set by the owner or superuser */
- if (flag & O_NOATIME && !inode_owner_or_capable(&init_user_ns, inode))
+ if (flag & O_NOATIME && !inode_owner_or_capable(user_ns, inode))
return -EPERM;
return 0;
@@ -2934,17 +2957,18 @@ static inline int open_to_namei_flags(int flag)
static int may_o_create(const struct path *dir, struct dentry *dentry, umode_t mode)
{
- struct user_namespace *s_user_ns;
+ struct user_namespace *s_user_ns, *user_ns;
int error = security_path_mknod(dir, dentry, mode, 0);
if (error)
return error;
+ user_ns = mnt_user_ns(dir->mnt);
s_user_ns = dir->dentry->d_sb->s_user_ns;
- if (!kuid_has_mapping(s_user_ns, current_fsuid()) ||
- !kgid_has_mapping(s_user_ns, current_fsgid()))
+ if (!kuid_has_mapping(s_user_ns, fsuid_into_mnt(user_ns)) ||
+ !kgid_has_mapping(s_user_ns, fsgid_into_mnt(user_ns)))
return -EOVERFLOW;
- error = inode_permission(&init_user_ns, dir->dentry->d_inode,
+ error = inode_permission(user_ns, dir->dentry->d_inode,
MAY_WRITE | MAY_EXEC);
if (error)
return error;
@@ -3238,7 +3262,7 @@ static int do_open(struct nameidata *nd,
return -EEXIST;
if (d_is_dir(nd->path.dentry))
return -EISDIR;
- error = may_create_in_sticky(nd->dir_mode, nd->dir_uid,
+ error = may_create_in_sticky(nd,
d_backing_inode(nd->path.dentry));
if (unlikely(error))
return error;
@@ -3540,7 +3564,7 @@ EXPORT_SYMBOL(user_path_create);
int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
{
bool is_whiteout = S_ISCHR(mode) && dev == WHITEOUT_DEV;
- int error = may_create(dir, dentry);
+ int error = may_create(&init_user_ns, dir, dentry);
if (error)
return error;
@@ -3641,7 +3665,7 @@ SYSCALL_DEFINE3(mknod, const char __user *, filename, umode_t, mode, unsigned, d
int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
- int error = may_create(dir, dentry);
+ int error = may_create(&init_user_ns, dir, dentry);
unsigned max_links = dir->i_sb->s_max_links;
if (error)
@@ -3702,7 +3726,7 @@ SYSCALL_DEFINE2(mkdir, const char __user *, pathname, umode_t, mode)
int vfs_rmdir(struct inode *dir, struct dentry *dentry)
{
- int error = may_delete(dir, dentry, 1);
+ int error = may_delete(&init_user_ns, dir, dentry, 1);
if (error)
return error;
@@ -3824,7 +3848,7 @@ SYSCALL_DEFINE1(rmdir, const char __user *, pathname)
int vfs_unlink(struct inode *dir, struct dentry *dentry, struct inode **delegated_inode)
{
struct inode *target = dentry->d_inode;
- int error = may_delete(dir, dentry, 0);
+ int error = may_delete(&init_user_ns, dir, dentry, 0);
if (error)
return error;
@@ -3956,7 +3980,7 @@ SYSCALL_DEFINE1(unlink, const char __user *, pathname)
int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname)
{
- int error = may_create(dir, dentry);
+ int error = may_create(&init_user_ns, dir, dentry);
if (error)
return error;
@@ -4045,7 +4069,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
if (!inode)
return -ENOENT;
- error = may_create(dir, new_dentry);
+ error = may_create(&init_user_ns, dir, new_dentry);
if (error)
return error;
@@ -4062,7 +4086,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
* be writen back improperly if their true value is unknown to
* the vfs.
*/
- if (HAS_UNMAPPED_ID(inode))
+ if (HAS_UNMAPPED_ID(&init_user_ns, inode))
return -EPERM;
if (!dir->i_op->link)
return -EPERM;
@@ -4237,6 +4261,7 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct inode **delegated_inode, unsigned int flags)
{
int error;
+ struct user_namespace *user_ns = &init_user_ns;
bool is_dir = d_is_dir(old_dentry);
struct inode *source = old_dentry->d_inode;
struct inode *target = new_dentry->d_inode;
@@ -4247,19 +4272,19 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
if (source == target)
return 0;
- error = may_delete(old_dir, old_dentry, is_dir);
+ error = may_delete(user_ns, old_dir, old_dentry, is_dir);
if (error)
return error;
if (!target) {
- error = may_create(new_dir, new_dentry);
+ error = may_create(user_ns, new_dir, new_dentry);
} else {
new_is_dir = d_is_dir(new_dentry);
if (!(flags & RENAME_EXCHANGE))
- error = may_delete(new_dir, new_dentry, is_dir);
+ error = may_delete(user_ns, new_dir, new_dentry, is_dir);
else
- error = may_delete(new_dir, new_dentry, new_is_dir);
+ error = may_delete(user_ns, new_dir, new_dentry, new_is_dir);
}
if (error)
return error;
diff --git a/fs/xattr.c b/fs/xattr.c
index 8c50b2a935e4..20376592dad6 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -98,7 +98,7 @@ xattr_permission(struct user_namespace *user_ns, struct inode *inode,
* to be writen back improperly if their true value is
* unknown to the vfs.
*/
- if (HAS_UNMAPPED_ID(inode))
+ if (HAS_UNMAPPED_ID(user_ns, inode))
return -EPERM;
}
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 696ad3e0df03..38aabad8f2aa 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2081,9 +2081,10 @@ static inline bool sb_rdonly(const struct super_block *sb) { return sb->s_flags
#define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \
(inode)->i_rdev == WHITEOUT_DEV)
-static inline bool HAS_UNMAPPED_ID(struct inode *inode)
+static inline bool HAS_UNMAPPED_ID(struct user_namespace *user_ns, struct inode *inode)
{
- return !uid_valid(inode->i_uid) || !gid_valid(inode->i_gid);
+ return !uid_valid(i_uid_into_mnt(user_ns, inode)) ||
+ !gid_valid(i_gid_into_mnt(user_ns, inode));
}
static inline enum rw_hint file_write_hint(struct file *file)
@@ -2807,7 +2808,8 @@ extern int notify_change(struct user_namespace *, struct dentry *,
struct iattr *, struct inode **);
extern int inode_permission(struct user_namespace *, struct inode *, int);
extern int generic_permission(struct user_namespace *, struct inode *, int);
-extern int __check_sticky(struct inode *dir, struct inode *inode);
+extern int __check_sticky(struct user_namespace *user_ns, struct inode *dir,
+ struct inode *inode);
static inline bool execute_ok(struct inode *inode)
{
@@ -3428,12 +3430,13 @@ static inline bool is_sxid(umode_t mode)
return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP));
}
-static inline int check_sticky(struct inode *dir, struct inode *inode)
+static inline int check_sticky(struct user_namespace *user_ns,
+ struct inode *dir, struct inode *inode)
{
if (!(dir->i_mode & S_ISVTX))
return 0;
- return __check_sticky(dir, inode);
+ return __check_sticky(user_ns, dir, inode);
}
static inline void inode_has_no_xattr(struct inode *inode)
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 17/38] namei: introduce struct renamedata
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (15 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 16/38] namei: handle idmapped mounts in may_*() helpers Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-12-01 10:53 ` Christoph Hellwig
2020-11-28 21:35 ` [PATCH v3 18/38] namei: prepare for idmapped mounts Christian Brauner
` (19 subsequent siblings)
36 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
In order to handle idmapped mounts we will extend the vfs rename helper to
take two new arguments in follow up patches. Since this operations already
takes a bunch of arguments add a simple struct renamedata (based on struct
nameidata) and make the current helper use it before we extend it.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
fs/cachefiles/namei.c | 9 +++++++--
fs/ecryptfs/inode.c | 10 +++++++---
fs/namei.c | 21 +++++++++++++++------
fs/nfsd/vfs.c | 8 +++++++-
fs/overlayfs/overlayfs.h | 9 ++++++++-
include/linux/fs.h | 12 +++++++++++-
6 files changed, 55 insertions(+), 14 deletions(-)
diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c
index ecc8ecbbfa5a..7b987de0babe 100644
--- a/fs/cachefiles/namei.c
+++ b/fs/cachefiles/namei.c
@@ -412,9 +412,14 @@ static int cachefiles_bury_object(struct cachefiles_cache *cache,
if (ret < 0) {
cachefiles_io_error(cache, "Rename security error %d", ret);
} else {
+ struct renamedata rd = {
+ .old_dir = d_inode(dir),
+ .old_dentry = rep,
+ .new_dir = d_inode(cache->graveyard),
+ .new_dentry = grave,
+ };
trace_cachefiles_rename(object, rep, grave, why);
- ret = vfs_rename(d_inode(dir), rep,
- d_inode(cache->graveyard), grave, NULL, 0);
+ ret = vfs_rename(&rd);
if (ret != 0 && ret != -ENOMEM)
cachefiles_io_error(cache,
"Rename failed with error %d", ret);
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index d98448c75051..838949ede439 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -590,6 +590,7 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
struct dentry *lower_new_dir_dentry;
struct dentry *trap;
struct inode *target_inode;
+ struct renamedata rd = {};
if (flags)
return -EINVAL;
@@ -619,9 +620,12 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
rc = -ENOTEMPTY;
goto out_lock;
}
- rc = vfs_rename(d_inode(lower_old_dir_dentry), lower_old_dentry,
- d_inode(lower_new_dir_dentry), lower_new_dentry,
- NULL, 0);
+
+ rd.old_dir = d_inode(lower_old_dir_dentry);
+ rd.old_dentry = lower_old_dentry;
+ rd.new_dir = d_inode(lower_new_dir_dentry);
+ rd.new_dentry = lower_new_dentry;
+ rc = vfs_rename(&rd);
if (rc)
goto out_lock;
if (target_inode)
diff --git a/fs/namei.c b/fs/namei.c
index 4dc842d1cd3a..0a2450de83bb 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -4256,12 +4256,15 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname
* ->i_mutex on parents, which works but leads to some truly excessive
* locking].
*/
-int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
- struct inode *new_dir, struct dentry *new_dentry,
- struct inode **delegated_inode, unsigned int flags)
+int vfs_rename(struct renamedata *rd)
{
int error;
struct user_namespace *user_ns = &init_user_ns;
+ struct inode *old_dir = rd->old_dir, *new_dir = rd->new_dir;
+ struct dentry *old_dentry = rd->old_dentry,
+ *new_dentry = rd->new_dentry;
+ struct inode **delegated_inode = rd->delegated_inode;
+ unsigned int flags = rd->flags;
bool is_dir = d_is_dir(old_dentry);
struct inode *source = old_dentry->d_inode;
struct inode *target = new_dentry->d_inode;
@@ -4385,6 +4388,7 @@ EXPORT_SYMBOL(vfs_rename);
static int do_renameat2(int olddfd, const char __user *oldname, int newdfd,
const char __user *newname, unsigned int flags)
{
+ struct renamedata rd;
struct dentry *old_dentry, *new_dentry;
struct dentry *trap;
struct path old_path, new_path;
@@ -4490,9 +4494,14 @@ static int do_renameat2(int olddfd, const char __user *oldname, int newdfd,
&new_path, new_dentry, flags);
if (error)
goto exit5;
- error = vfs_rename(old_path.dentry->d_inode, old_dentry,
- new_path.dentry->d_inode, new_dentry,
- &delegated_inode, flags);
+
+ rd.old_dir = old_path.dentry->d_inode;
+ rd.old_dentry = old_dentry;
+ rd.new_dir = new_path.dentry->d_inode;
+ rd.new_dentry = new_dentry;
+ rd.delegated_inode = &delegated_inode;
+ rd.flags = flags;
+ error = vfs_rename(&rd);
exit5:
dput(new_dentry);
exit4:
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 9a0e0e5b34f5..3d7a8cd61098 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1787,7 +1787,13 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
has_cached = true;
goto out_dput_old;
} else {
- host_err = vfs_rename(fdir, odentry, tdir, ndentry, NULL, 0);
+ struct renamedata rd = {
+ .old_dir = fdir,
+ .old_dentry = odentry,
+ .new_dir = tdir,
+ .new_dentry = ndentry,
+ };
+ host_err = vfs_rename(&rd);
if (!host_err) {
host_err = commit_metadata(tfhp);
if (!host_err)
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index bf26fb3fa2c1..73da8710b0f0 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -212,9 +212,16 @@ static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry,
unsigned int flags)
{
int err;
+ struct renamedata rd = {
+ .old_dir = olddir,
+ .old_dentry = olddentry,
+ .new_dir = newdir,
+ .new_dentry = newdentry,
+ .flags = flags,
+ };
pr_debug("rename(%pd2, %pd2, 0x%x)\n", olddentry, newdentry, flags);
- err = vfs_rename(olddir, olddentry, newdir, newdentry, NULL, flags);
+ err = vfs_rename(&rd);
if (err) {
pr_debug("...rename(%pd2, %pd2, ...) = %i\n",
olddentry, newdentry, err);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 38aabad8f2aa..3a27d84df7fb 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1772,7 +1772,17 @@ extern int vfs_symlink(struct inode *, struct dentry *, const char *);
extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **);
extern int vfs_rmdir(struct inode *, struct dentry *);
extern int vfs_unlink(struct inode *, struct dentry *, struct inode **);
-extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **, unsigned int);
+
+struct renamedata {
+ struct inode *old_dir;
+ struct dentry *old_dentry;
+ struct inode *new_dir;
+ struct dentry *new_dentry;
+ struct inode **delegated_inode;
+ unsigned int flags;
+} __randomize_layout;
+
+extern int vfs_rename(struct renamedata *);
static inline int vfs_whiteout(struct inode *dir, struct dentry *dentry)
{
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 18/38] namei: prepare for idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (16 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 17/38] namei: introduce struct renamedata Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 19/38] open: handle idmapped mounts in do_truncate() Christian Brauner
` (18 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
The various vfs_*() helpers are called by filesystems or by the vfs itself to
perform core operations create, link, mkdir, mknod, rename, rmdir, tmpfile and
unlink. Enable them to handle idmapped mounts. If the inode is accessed through
an idmapped mount it is mapped according to the mount's user namespace.
Afterwards the checks and operations are identical to non-idmapped mounts. If
the initial user namespace is passed nothing changes so non-idmapped mounts will
see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Don't pollute the vfs with additional helpers simply extend the existing
helpers with an additional argument and switch all callers.
/* v3 */
unchanged
---
drivers/base/devtmpfs.c | 8 +--
fs/cachefiles/namei.c | 10 ++--
fs/ecryptfs/inode.c | 22 ++++----
fs/init.c | 12 ++---
fs/namei.c | 108 +++++++++++++++++++++++++--------------
fs/nfsd/nfs4recover.c | 6 +--
fs/nfsd/vfs.c | 19 ++++---
fs/overlayfs/dir.c | 4 +-
fs/overlayfs/overlayfs.h | 20 ++++----
include/linux/fs.h | 25 +++++----
ipc/mqueue.c | 2 +-
net/unix/af_unix.c | 2 +-
12 files changed, 144 insertions(+), 94 deletions(-)
diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c
index 2e0c3cdb4184..fd4e86c58111 100644
--- a/drivers/base/devtmpfs.c
+++ b/drivers/base/devtmpfs.c
@@ -162,7 +162,7 @@ static int dev_mkdir(const char *name, umode_t mode)
if (IS_ERR(dentry))
return PTR_ERR(dentry);
- err = vfs_mkdir(d_inode(path.dentry), dentry, mode);
+ err = vfs_mkdir(&init_user_ns, d_inode(path.dentry), dentry, mode);
if (!err)
/* mark as kernel-created inode */
d_inode(dentry)->i_private = &thread;
@@ -212,7 +212,7 @@ static int handle_create(const char *nodename, umode_t mode, kuid_t uid,
if (IS_ERR(dentry))
return PTR_ERR(dentry);
- err = vfs_mknod(d_inode(path.dentry), dentry, mode, dev->devt);
+ err = vfs_mknod(&init_user_ns, d_inode(path.dentry), dentry, mode, dev->devt);
if (!err) {
struct iattr newattrs;
@@ -242,7 +242,7 @@ static int dev_rmdir(const char *name)
return PTR_ERR(dentry);
if (d_really_is_positive(dentry)) {
if (d_inode(dentry)->i_private == &thread)
- err = vfs_rmdir(d_inode(parent.dentry), dentry);
+ err = vfs_rmdir(&init_user_ns, d_inode(parent.dentry), dentry);
else
err = -EPERM;
} else {
@@ -330,7 +330,7 @@ static int handle_remove(const char *nodename, struct device *dev)
inode_lock(d_inode(dentry));
notify_change(&init_user_ns, dentry, &newattrs, NULL);
inode_unlock(d_inode(dentry));
- err = vfs_unlink(d_inode(parent.dentry), dentry, NULL);
+ err = vfs_unlink(&init_user_ns, d_inode(parent.dentry), dentry, NULL);
if (!err || err == -ENOENT)
deleted = 1;
}
diff --git a/fs/cachefiles/namei.c b/fs/cachefiles/namei.c
index 7b987de0babe..ae01fac0a80c 100644
--- a/fs/cachefiles/namei.c
+++ b/fs/cachefiles/namei.c
@@ -311,7 +311,7 @@ static int cachefiles_bury_object(struct cachefiles_cache *cache,
cachefiles_io_error(cache, "Unlink security error");
} else {
trace_cachefiles_unlink(object, rep, why);
- ret = vfs_unlink(d_inode(dir), rep, NULL);
+ ret = vfs_unlink(&init_user_ns, d_inode(dir), rep, NULL);
if (preemptive)
cachefiles_mark_object_buried(cache, rep, why);
@@ -413,8 +413,10 @@ static int cachefiles_bury_object(struct cachefiles_cache *cache,
cachefiles_io_error(cache, "Rename security error %d", ret);
} else {
struct renamedata rd = {
+ .old_user_ns = &init_user_ns,
.old_dir = d_inode(dir),
.old_dentry = rep,
+ .new_user_ns = &init_user_ns,
.new_dir = d_inode(cache->graveyard),
.new_dentry = grave,
};
@@ -566,7 +568,7 @@ int cachefiles_walk_to_object(struct cachefiles_object *parent,
if (ret < 0)
goto create_error;
start = jiffies;
- ret = vfs_mkdir(d_inode(dir), next, 0);
+ ret = vfs_mkdir(&init_user_ns, d_inode(dir), next, 0);
cachefiles_hist(cachefiles_mkdir_histogram, start);
if (!key)
trace_cachefiles_mkdir(object, next, ret);
@@ -602,7 +604,7 @@ int cachefiles_walk_to_object(struct cachefiles_object *parent,
if (ret < 0)
goto create_error;
start = jiffies;
- ret = vfs_create(d_inode(dir), next, S_IFREG, true);
+ ret = vfs_create(&init_user_ns, d_inode(dir), next, S_IFREG, true);
cachefiles_hist(cachefiles_create_histogram, start);
trace_cachefiles_create(object, next, ret);
if (ret < 0)
@@ -796,7 +798,7 @@ struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache,
ret = security_path_mkdir(&path, subdir, 0700);
if (ret < 0)
goto mkdir_error;
- ret = vfs_mkdir(d_inode(dir), subdir, 0700);
+ ret = vfs_mkdir(&init_user_ns, d_inode(dir), subdir, 0700);
if (ret < 0)
goto mkdir_error;
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index 838949ede439..42066c5613ca 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -141,7 +141,7 @@ static int ecryptfs_do_unlink(struct inode *dir, struct dentry *dentry,
else if (d_unhashed(lower_dentry))
rc = -EINVAL;
else
- rc = vfs_unlink(lower_dir_inode, lower_dentry, NULL);
+ rc = vfs_unlink(&init_user_ns, lower_dir_inode, lower_dentry, NULL);
if (rc) {
printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
goto out_unlock;
@@ -180,7 +180,8 @@ ecryptfs_do_create(struct inode *directory_inode,
lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
lower_dir_dentry = lock_parent(lower_dentry);
- rc = vfs_create(d_inode(lower_dir_dentry), lower_dentry, mode, true);
+ rc = vfs_create(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry,
+ mode, true);
if (rc) {
printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
"rc = [%d]\n", __func__, rc);
@@ -190,7 +191,7 @@ ecryptfs_do_create(struct inode *directory_inode,
inode = __ecryptfs_get_inode(d_inode(lower_dentry),
directory_inode->i_sb);
if (IS_ERR(inode)) {
- vfs_unlink(d_inode(lower_dir_dentry), lower_dentry, NULL);
+ vfs_unlink(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry, NULL);
goto out_lock;
}
fsstack_copy_attr_times(directory_inode, d_inode(lower_dir_dentry));
@@ -436,8 +437,8 @@ static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
dget(lower_old_dentry);
dget(lower_new_dentry);
lower_dir_dentry = lock_parent(lower_new_dentry);
- rc = vfs_link(lower_old_dentry, d_inode(lower_dir_dentry),
- lower_new_dentry, NULL);
+ rc = vfs_link(lower_old_dentry, &init_user_ns,
+ d_inode(lower_dir_dentry), lower_new_dentry, NULL);
if (rc || d_really_is_negative(lower_new_dentry))
goto out_lock;
rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb);
@@ -481,7 +482,7 @@ static int ecryptfs_symlink(struct inode *dir, struct dentry *dentry,
strlen(symname));
if (rc)
goto out_lock;
- rc = vfs_symlink(d_inode(lower_dir_dentry), lower_dentry,
+ rc = vfs_symlink(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry,
encoded_symname);
kfree(encoded_symname);
if (rc || d_really_is_negative(lower_dentry))
@@ -507,7 +508,7 @@ static int ecryptfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode
lower_dentry = ecryptfs_dentry_to_lower(dentry);
lower_dir_dentry = lock_parent(lower_dentry);
- rc = vfs_mkdir(d_inode(lower_dir_dentry), lower_dentry, mode);
+ rc = vfs_mkdir(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry, mode);
if (rc || d_really_is_negative(lower_dentry))
goto out;
rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
@@ -541,7 +542,7 @@ static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
else if (d_unhashed(lower_dentry))
rc = -EINVAL;
else
- rc = vfs_rmdir(lower_dir_inode, lower_dentry);
+ rc = vfs_rmdir(&init_user_ns, lower_dir_inode, lower_dentry);
if (!rc) {
clear_nlink(d_inode(dentry));
fsstack_copy_attr_times(dir, lower_dir_inode);
@@ -563,7 +564,8 @@ ecryptfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev
lower_dentry = ecryptfs_dentry_to_lower(dentry);
lower_dir_dentry = lock_parent(lower_dentry);
- rc = vfs_mknod(d_inode(lower_dir_dentry), lower_dentry, mode, dev);
+ rc = vfs_mknod(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry,
+ mode, dev);
if (rc || d_really_is_negative(lower_dentry))
goto out;
rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
@@ -621,8 +623,10 @@ ecryptfs_rename(struct inode *old_dir, struct dentry *old_dentry,
goto out_lock;
}
+ rd.old_user_ns = &init_user_ns;
rd.old_dir = d_inode(lower_old_dir_dentry);
rd.old_dentry = lower_old_dentry;
+ rd.new_user_ns = &init_user_ns;
rd.new_dir = d_inode(lower_new_dir_dentry);
rd.new_dentry = lower_new_dentry;
rc = vfs_rename(&rd);
diff --git a/fs/init.c b/fs/init.c
index 2b4842f4802b..76f493600030 100644
--- a/fs/init.c
+++ b/fs/init.c
@@ -160,8 +160,8 @@ int __init init_mknod(const char *filename, umode_t mode, unsigned int dev)
mode &= ~current_umask();
error = security_path_mknod(&path, dentry, mode, dev);
if (!error)
- error = vfs_mknod(path.dentry->d_inode, dentry, mode,
- new_decode_dev(dev));
+ error = vfs_mknod(&init_user_ns, path.dentry->d_inode, dentry,
+ mode, new_decode_dev(dev));
done_path_create(&path, dentry);
return error;
}
@@ -190,8 +190,8 @@ int __init init_link(const char *oldname, const char *newname)
error = security_path_link(old_path.dentry, &new_path, new_dentry);
if (error)
goto out_dput;
- error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry,
- NULL);
+ error = vfs_link(old_path.dentry, &init_user_ns,
+ new_path.dentry->d_inode, new_dentry, NULL);
out_dput:
done_path_create(&new_path, new_dentry);
out:
@@ -210,7 +210,7 @@ int __init init_symlink(const char *oldname, const char *newname)
return PTR_ERR(dentry);
error = security_path_symlink(&path, dentry, oldname);
if (!error)
- error = vfs_symlink(path.dentry->d_inode, dentry, oldname);
+ error = vfs_symlink(&init_user_ns, path.dentry->d_inode, dentry, oldname);
done_path_create(&path, dentry);
return error;
}
@@ -233,7 +233,7 @@ int __init init_mkdir(const char *pathname, umode_t mode)
mode &= ~current_umask();
error = security_path_mkdir(&path, dentry, mode);
if (!error)
- error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
+ error = vfs_mkdir(&init_user_ns, path.dentry->d_inode, dentry, mode);
done_path_create(&path, dentry);
return error;
}
diff --git a/fs/namei.c b/fs/namei.c
index 0a2450de83bb..b91bf923d22c 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2820,10 +2820,10 @@ void unlock_rename(struct dentry *p1, struct dentry *p2)
}
EXPORT_SYMBOL(unlock_rename);
-int vfs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
- bool want_excl)
+int vfs_create(struct user_namespace *user_ns, struct inode *dir,
+ struct dentry *dentry, umode_t mode, bool want_excl)
{
- int error = may_create(&init_user_ns, dir, dentry);
+ int error = may_create(user_ns, dir, dentry);
if (error)
return error;
@@ -3298,7 +3298,8 @@ static int do_open(struct nameidata *nd,
return error;
}
-struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag)
+struct dentry *vfs_tmpfile(struct user_namespace *user_ns,
+ struct dentry *dentry, umode_t mode, int open_flag)
{
struct dentry *child = NULL;
struct inode *dir = dentry->d_inode;
@@ -3306,7 +3307,7 @@ struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag)
int error;
/* we want directory to be writable */
- error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
+ error = inode_permission(user_ns, dir, MAY_WRITE | MAY_EXEC);
if (error)
goto out_err;
error = -EOPNOTSUPP;
@@ -3341,6 +3342,7 @@ static int do_tmpfile(struct nameidata *nd, unsigned flags,
const struct open_flags *op,
struct file *file)
{
+ struct user_namespace *user_ns;
struct dentry *child;
struct path path;
int error = path_lookupat(nd, flags | LOOKUP_DIRECTORY, &path);
@@ -3349,7 +3351,8 @@ static int do_tmpfile(struct nameidata *nd, unsigned flags,
error = mnt_want_write(path.mnt);
if (unlikely(error))
goto out;
- child = vfs_tmpfile(path.dentry, op->mode, op->open_flag);
+ user_ns = mnt_user_ns(path.mnt);
+ child = vfs_tmpfile(user_ns, path.dentry, op->mode, op->open_flag);
error = PTR_ERR(child);
if (IS_ERR(child))
goto out2;
@@ -3561,10 +3564,11 @@ inline struct dentry *user_path_create(int dfd, const char __user *pathname,
}
EXPORT_SYMBOL(user_path_create);
-int vfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
+int vfs_mknod(struct user_namespace *user_ns, struct inode *dir,
+ struct dentry *dentry, umode_t mode, dev_t dev)
{
bool is_whiteout = S_ISCHR(mode) && dev == WHITEOUT_DEV;
- int error = may_create(&init_user_ns, dir, dentry);
+ int error = may_create(user_ns, dir, dentry);
if (error)
return error;
@@ -3611,6 +3615,7 @@ static int may_mknod(umode_t mode)
static long do_mknodat(int dfd, const char __user *filename, umode_t mode,
unsigned int dev)
{
+ struct user_namespace *user_ns;
struct dentry *dentry;
struct path path;
int error;
@@ -3629,18 +3634,22 @@ static long do_mknodat(int dfd, const char __user *filename, umode_t mode,
error = security_path_mknod(&path, dentry, mode, dev);
if (error)
goto out;
+
+ user_ns = mnt_user_ns(path.mnt);
switch (mode & S_IFMT) {
case 0: case S_IFREG:
- error = vfs_create(path.dentry->d_inode,dentry,mode,true);
+ error = vfs_create(user_ns, path.dentry->d_inode,
+ dentry, mode, true);
if (!error)
ima_post_path_mknod(dentry);
break;
case S_IFCHR: case S_IFBLK:
- error = vfs_mknod(path.dentry->d_inode,dentry,mode,
- new_decode_dev(dev));
+ error = vfs_mknod(user_ns, path.dentry->d_inode, dentry,
+ mode, new_decode_dev(dev));
break;
case S_IFIFO: case S_IFSOCK:
- error = vfs_mknod(path.dentry->d_inode,dentry,mode,0);
+ error = vfs_mknod(user_ns, path.dentry->d_inode, dentry,
+ mode, 0);
break;
}
out:
@@ -3663,9 +3672,10 @@ SYSCALL_DEFINE3(mknod, const char __user *, filename, umode_t, mode, unsigned, d
return do_mknodat(AT_FDCWD, filename, mode, dev);
}
-int vfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
+int vfs_mkdir(struct user_namespace *user_ns, struct inode *dir,
+ struct dentry *dentry, umode_t mode)
{
- int error = may_create(&init_user_ns, dir, dentry);
+ int error = may_create(user_ns, dir, dentry);
unsigned max_links = dir->i_sb->s_max_links;
if (error)
@@ -3704,8 +3714,11 @@ static long do_mkdirat(int dfd, const char __user *pathname, umode_t mode)
if (!IS_POSIXACL(path.dentry->d_inode))
mode &= ~current_umask();
error = security_path_mkdir(&path, dentry, mode);
- if (!error)
- error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
+ if (!error) {
+ struct user_namespace *user_ns;
+ user_ns = mnt_user_ns(path.mnt);
+ error = vfs_mkdir(user_ns, path.dentry->d_inode, dentry, mode);
+ }
done_path_create(&path, dentry);
if (retry_estale(error, lookup_flags)) {
lookup_flags |= LOOKUP_REVAL;
@@ -3724,9 +3737,10 @@ SYSCALL_DEFINE2(mkdir, const char __user *, pathname, umode_t, mode)
return do_mkdirat(AT_FDCWD, pathname, mode);
}
-int vfs_rmdir(struct inode *dir, struct dentry *dentry)
+int vfs_rmdir(struct user_namespace *user_ns, struct inode *dir,
+ struct dentry *dentry)
{
- int error = may_delete(&init_user_ns, dir, dentry, 1);
+ int error = may_delete(user_ns, dir, dentry, 1);
if (error)
return error;
@@ -3766,6 +3780,7 @@ EXPORT_SYMBOL(vfs_rmdir);
long do_rmdir(int dfd, struct filename *name)
{
+ struct user_namespace *user_ns;
int error = 0;
struct dentry *dentry;
struct path path;
@@ -3806,7 +3821,8 @@ long do_rmdir(int dfd, struct filename *name)
error = security_path_rmdir(&path, dentry);
if (error)
goto exit3;
- error = vfs_rmdir(path.dentry->d_inode, dentry);
+ user_ns = mnt_user_ns(path.mnt);
+ error = vfs_rmdir(user_ns, path.dentry->d_inode, dentry);
exit3:
dput(dentry);
exit2:
@@ -3845,10 +3861,11 @@ SYSCALL_DEFINE1(rmdir, const char __user *, pathname)
* be appropriate for callers that expect the underlying filesystem not
* to be NFS exported.
*/
-int vfs_unlink(struct inode *dir, struct dentry *dentry, struct inode **delegated_inode)
+int vfs_unlink(struct user_namespace *user_ns, struct inode *dir,
+ struct dentry *dentry, struct inode **delegated_inode)
{
struct inode *target = dentry->d_inode;
- int error = may_delete(&init_user_ns, dir, dentry, 0);
+ int error = may_delete(user_ns, dir, dentry, 0);
if (error)
return error;
@@ -3919,6 +3936,8 @@ long do_unlinkat(int dfd, struct filename *name)
dentry = __lookup_hash(&last, path.dentry, lookup_flags);
error = PTR_ERR(dentry);
if (!IS_ERR(dentry)) {
+ struct user_namespace *user_ns;
+
/* Why not before? Because we want correct error value */
if (last.name[last.len])
goto slashes;
@@ -3929,7 +3948,8 @@ long do_unlinkat(int dfd, struct filename *name)
error = security_path_unlink(&path, dentry);
if (error)
goto exit2;
- error = vfs_unlink(path.dentry->d_inode, dentry, &delegated_inode);
+ user_ns = mnt_user_ns(path.mnt);
+ error = vfs_unlink(user_ns, path.dentry->d_inode, dentry, &delegated_inode);
exit2:
dput(dentry);
}
@@ -3978,9 +3998,10 @@ SYSCALL_DEFINE1(unlink, const char __user *, pathname)
return do_unlinkat(AT_FDCWD, getname(pathname));
}
-int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname)
+int vfs_symlink(struct user_namespace *user_ns, struct inode *dir,
+ struct dentry *dentry, const char *oldname)
{
- int error = may_create(&init_user_ns, dir, dentry);
+ int error = may_create(user_ns, dir, dentry);
if (error)
return error;
@@ -4018,8 +4039,12 @@ static long do_symlinkat(const char __user *oldname, int newdfd,
goto out_putname;
error = security_path_symlink(&path, dentry, from->name);
- if (!error)
- error = vfs_symlink(path.dentry->d_inode, dentry, from->name);
+ if (!error) {
+ struct user_namespace *user_ns;
+ user_ns = mnt_user_ns(path.mnt);
+ error = vfs_symlink(user_ns, path.dentry->d_inode, dentry,
+ from->name);
+ }
done_path_create(&path, dentry);
if (retry_estale(error, lookup_flags)) {
lookup_flags |= LOOKUP_REVAL;
@@ -4044,6 +4069,7 @@ SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newn
/**
* vfs_link - create a new link
* @old_dentry: object to be linked
+ * @user_ns: the user namespace of the mount
* @dir: new parent
* @new_dentry: where to create the new link
* @delegated_inode: returns inode needing a delegation break
@@ -4060,7 +4086,9 @@ SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newn
* be appropriate for callers that expect the underlying filesystem not
* to be NFS exported.
*/
-int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry, struct inode **delegated_inode)
+int vfs_link(struct dentry *old_dentry, struct user_namespace *user_ns,
+ struct inode *dir, struct dentry *new_dentry,
+ struct inode **delegated_inode)
{
struct inode *inode = old_dentry->d_inode;
unsigned max_links = dir->i_sb->s_max_links;
@@ -4069,7 +4097,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
if (!inode)
return -ENOENT;
- error = may_create(&init_user_ns, dir, new_dentry);
+ error = may_create(user_ns, dir, new_dentry);
if (error)
return error;
@@ -4086,7 +4114,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de
* be writen back improperly if their true value is unknown to
* the vfs.
*/
- if (HAS_UNMAPPED_ID(&init_user_ns, inode))
+ if (HAS_UNMAPPED_ID(user_ns, inode))
return -EPERM;
if (!dir->i_op->link)
return -EPERM;
@@ -4133,6 +4161,7 @@ EXPORT_SYMBOL(vfs_link);
static int do_linkat(int olddfd, const char __user *oldname, int newdfd,
const char __user *newname, int flags)
{
+ struct user_namespace *user_ns;
struct dentry *new_dentry;
struct path old_path, new_path;
struct inode *delegated_inode = NULL;
@@ -4174,7 +4203,9 @@ static int do_linkat(int olddfd, const char __user *oldname, int newdfd,
error = security_path_link(old_path.dentry, &new_path, new_dentry);
if (error)
goto out_dput;
- error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry, &delegated_inode);
+ user_ns = mnt_user_ns(new_path.mnt);
+ error = vfs_link(old_path.dentry, user_ns, new_path.dentry->d_inode,
+ new_dentry, &delegated_inode);
out_dput:
done_path_create(&new_path, new_dentry);
if (delegated_inode) {
@@ -4208,8 +4239,10 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname
/**
* vfs_rename - rename a filesystem object
+ * @old_user_ns: user namespace the old inode is accessed from
* @old_dir: parent of source
* @old_dentry: source
+ * @new_user_ns: user namespace the old inode is accessed from
* @new_dir: parent of destination
* @new_dentry: destination
* @delegated_inode: returns an inode needing a delegation break
@@ -4259,7 +4292,6 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname
int vfs_rename(struct renamedata *rd)
{
int error;
- struct user_namespace *user_ns = &init_user_ns;
struct inode *old_dir = rd->old_dir, *new_dir = rd->new_dir;
struct dentry *old_dentry = rd->old_dentry,
*new_dentry = rd->new_dentry;
@@ -4275,19 +4307,19 @@ int vfs_rename(struct renamedata *rd)
if (source == target)
return 0;
- error = may_delete(user_ns, old_dir, old_dentry, is_dir);
+ error = may_delete(rd->old_user_ns, old_dir, old_dentry, is_dir);
if (error)
return error;
if (!target) {
- error = may_create(user_ns, new_dir, new_dentry);
+ error = may_create(rd->new_user_ns, new_dir, new_dentry);
} else {
new_is_dir = d_is_dir(new_dentry);
if (!(flags & RENAME_EXCHANGE))
- error = may_delete(user_ns, new_dir, new_dentry, is_dir);
+ error = may_delete(rd->new_user_ns, new_dir, new_dentry, is_dir);
else
- error = may_delete(user_ns, new_dir, new_dentry, new_is_dir);
+ error = may_delete(rd->new_user_ns, new_dir, new_dentry, new_is_dir);
}
if (error)
return error;
@@ -4301,12 +4333,12 @@ int vfs_rename(struct renamedata *rd)
*/
if (new_dir != old_dir) {
if (is_dir) {
- error = inode_permission(&init_user_ns, source, MAY_WRITE);
+ error = inode_permission(rd->old_user_ns, source, MAY_WRITE);
if (error)
return error;
}
if ((flags & RENAME_EXCHANGE) && new_is_dir) {
- error = inode_permission(&init_user_ns, target, MAY_WRITE);
+ error = inode_permission(rd->new_user_ns, target, MAY_WRITE);
if (error)
return error;
}
@@ -4497,8 +4529,10 @@ static int do_renameat2(int olddfd, const char __user *oldname, int newdfd,
rd.old_dir = old_path.dentry->d_inode;
rd.old_dentry = old_dentry;
+ rd.old_user_ns = mnt_user_ns(old_path.mnt);
rd.new_dir = new_path.dentry->d_inode;
rd.new_dentry = new_dentry;
+ rd.new_user_ns = mnt_user_ns(new_path.mnt);
rd.delegated_inode = &delegated_inode;
rd.flags = flags;
error = vfs_rename(&rd);
diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c
index 186fa2c2c6ba..891395c6c7d3 100644
--- a/fs/nfsd/nfs4recover.c
+++ b/fs/nfsd/nfs4recover.c
@@ -233,7 +233,7 @@ nfsd4_create_clid_dir(struct nfs4_client *clp)
* as well be forgiving and just succeed silently.
*/
goto out_put;
- status = vfs_mkdir(d_inode(dir), dentry, S_IRWXU);
+ status = vfs_mkdir(&init_user_ns, d_inode(dir), dentry, S_IRWXU);
out_put:
dput(dentry);
out_unlock:
@@ -353,7 +353,7 @@ nfsd4_unlink_clid_dir(char *name, int namlen, struct nfsd_net *nn)
status = -ENOENT;
if (d_really_is_negative(dentry))
goto out;
- status = vfs_rmdir(d_inode(dir), dentry);
+ status = vfs_rmdir(&init_user_ns, d_inode(dir), dentry);
out:
dput(dentry);
out_unlock:
@@ -443,7 +443,7 @@ purge_old(struct dentry *parent, struct dentry *child, struct nfsd_net *nn)
if (nfs4_has_reclaimed_state(name, nn))
goto out_free;
- status = vfs_rmdir(d_inode(parent), child);
+ status = vfs_rmdir(&init_user_ns, d_inode(parent), child);
if (status)
printk("failed to remove client recovery directory %pd\n",
child);
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 3d7a8cd61098..49837c995377 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1245,12 +1245,12 @@ nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp,
host_err = 0;
switch (type) {
case S_IFREG:
- host_err = vfs_create(dirp, dchild, iap->ia_mode, true);
+ host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true);
if (!host_err)
nfsd_check_ignore_resizing(iap);
break;
case S_IFDIR:
- host_err = vfs_mkdir(dirp, dchild, iap->ia_mode);
+ host_err = vfs_mkdir(&init_user_ns, dirp, dchild, iap->ia_mode);
if (!host_err && unlikely(d_unhashed(dchild))) {
struct dentry *d;
d = lookup_one_len(dchild->d_name.name,
@@ -1278,7 +1278,8 @@ nfsd_create_locked(struct svc_rqst *rqstp, struct svc_fh *fhp,
case S_IFBLK:
case S_IFIFO:
case S_IFSOCK:
- host_err = vfs_mknod(dirp, dchild, iap->ia_mode, rdev);
+ host_err = vfs_mknod(&init_user_ns, dirp, dchild,
+ iap->ia_mode, rdev);
break;
default:
printk(KERN_WARNING "nfsd: bad file type %o in nfsd_create\n",
@@ -1476,7 +1477,7 @@ do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
if (!IS_POSIXACL(dirp))
iap->ia_mode &= ~current_umask();
- host_err = vfs_create(dirp, dchild, iap->ia_mode, true);
+ host_err = vfs_create(&init_user_ns, dirp, dchild, iap->ia_mode, true);
if (host_err < 0) {
fh_drop_write(fhp);
goto out_nfserr;
@@ -1600,7 +1601,7 @@ nfsd_symlink(struct svc_rqst *rqstp, struct svc_fh *fhp,
if (IS_ERR(dnew))
goto out_nfserr;
- host_err = vfs_symlink(d_inode(dentry), dnew, path);
+ host_err = vfs_symlink(&init_user_ns, d_inode(dentry), dnew, path);
err = nfserrno(host_err);
if (!err)
err = nfserrno(commit_metadata(fhp));
@@ -1668,7 +1669,7 @@ nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
err = nfserr_noent;
if (d_really_is_negative(dold))
goto out_dput;
- host_err = vfs_link(dold, dirp, dnew, NULL);
+ host_err = vfs_link(dold, &init_user_ns, dirp, dnew, NULL);
if (!host_err) {
err = nfserrno(commit_metadata(ffhp));
if (!err)
@@ -1788,8 +1789,10 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
goto out_dput_old;
} else {
struct renamedata rd = {
+ .old_user_ns = &init_user_ns,
.old_dir = fdir,
.old_dentry = odentry,
+ .new_user_ns = &init_user_ns,
.new_dir = tdir,
.new_dentry = ndentry,
};
@@ -1879,9 +1882,9 @@ nfsd_unlink(struct svc_rqst *rqstp, struct svc_fh *fhp, int type,
if (type != S_IFDIR) {
nfsd_close_cached_files(rdentry);
- host_err = vfs_unlink(dirp, rdentry, NULL);
+ host_err = vfs_unlink(&init_user_ns, dirp, rdentry, NULL);
} else {
- host_err = vfs_rmdir(dirp, rdentry);
+ host_err = vfs_rmdir(&init_user_ns, dirp, rdentry);
}
if (!host_err)
diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c
index a1794c838b78..fa6e3fde9a26 100644
--- a/fs/overlayfs/dir.c
+++ b/fs/overlayfs/dir.c
@@ -821,9 +821,9 @@ static int ovl_remove_upper(struct dentry *dentry, bool is_dir,
goto out_dput_upper;
if (is_dir)
- err = vfs_rmdir(dir, upper);
+ err = vfs_rmdir(&init_user_ns, dir, upper);
else
- err = vfs_unlink(dir, upper, NULL);
+ err = vfs_unlink(&init_user_ns, dir, upper, NULL);
ovl_dir_modified(dentry->d_parent, ovl_type_origin(dentry));
/*
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 73da8710b0f0..0249ea876dc3 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -121,7 +121,7 @@ static inline const char *ovl_xattr(struct ovl_fs *ofs, enum ovl_xattr ox)
static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry)
{
- int err = vfs_rmdir(dir, dentry);
+ int err = vfs_rmdir(&init_user_ns, dir, dentry);
pr_debug("rmdir(%pd2) = %i\n", dentry, err);
return err;
@@ -129,7 +129,7 @@ static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry)
static inline int ovl_do_unlink(struct inode *dir, struct dentry *dentry)
{
- int err = vfs_unlink(dir, dentry, NULL);
+ int err = vfs_unlink(&init_user_ns, dir, dentry, NULL);
pr_debug("unlink(%pd2) = %i\n", dentry, err);
return err;
@@ -138,7 +138,7 @@ static inline int ovl_do_unlink(struct inode *dir, struct dentry *dentry)
static inline int ovl_do_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *new_dentry)
{
- int err = vfs_link(old_dentry, dir, new_dentry, NULL);
+ int err = vfs_link(old_dentry, &init_user_ns, dir, new_dentry, NULL);
pr_debug("link(%pd2, %pd2) = %i\n", old_dentry, new_dentry, err);
return err;
@@ -147,7 +147,7 @@ static inline int ovl_do_link(struct dentry *old_dentry, struct inode *dir,
static inline int ovl_do_create(struct inode *dir, struct dentry *dentry,
umode_t mode)
{
- int err = vfs_create(dir, dentry, mode, true);
+ int err = vfs_create(&init_user_ns, dir, dentry, mode, true);
pr_debug("create(%pd2, 0%o) = %i\n", dentry, mode, err);
return err;
@@ -156,7 +156,7 @@ static inline int ovl_do_create(struct inode *dir, struct dentry *dentry,
static inline int ovl_do_mkdir(struct inode *dir, struct dentry *dentry,
umode_t mode)
{
- int err = vfs_mkdir(dir, dentry, mode);
+ int err = vfs_mkdir(&init_user_ns, dir, dentry, mode);
pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry, mode, err);
return err;
}
@@ -164,7 +164,7 @@ static inline int ovl_do_mkdir(struct inode *dir, struct dentry *dentry,
static inline int ovl_do_mknod(struct inode *dir, struct dentry *dentry,
umode_t mode, dev_t dev)
{
- int err = vfs_mknod(dir, dentry, mode, dev);
+ int err = vfs_mknod(&init_user_ns, dir, dentry, mode, dev);
pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n", dentry, mode, dev, err);
return err;
@@ -173,7 +173,7 @@ static inline int ovl_do_mknod(struct inode *dir, struct dentry *dentry,
static inline int ovl_do_symlink(struct inode *dir, struct dentry *dentry,
const char *oldname)
{
- int err = vfs_symlink(dir, dentry, oldname);
+ int err = vfs_symlink(&init_user_ns, dir, dentry, oldname);
pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname, dentry, err);
return err;
@@ -213,8 +213,10 @@ static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry,
{
int err;
struct renamedata rd = {
+ .old_user_ns = &init_user_ns,
.old_dir = olddir,
.old_dentry = olddentry,
+ .new_user_ns = &init_user_ns,
.new_dir = newdir,
.new_dentry = newdentry,
.flags = flags,
@@ -231,14 +233,14 @@ static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry,
static inline int ovl_do_whiteout(struct inode *dir, struct dentry *dentry)
{
- int err = vfs_whiteout(dir, dentry);
+ int err = vfs_whiteout(&init_user_ns, dir, dentry);
pr_debug("whiteout(%pd2) = %i\n", dentry, err);
return err;
}
static inline struct dentry *ovl_do_tmpfile(struct dentry *dentry, umode_t mode)
{
- struct dentry *ret = vfs_tmpfile(dentry, mode, 0);
+ struct dentry *ret = vfs_tmpfile(&init_user_ns, dentry, mode, 0);
int err = PTR_ERR_OR_ZERO(ret);
pr_debug("tmpfile(%pd2, 0%o) = %i\n", dentry, mode, err);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 3a27d84df7fb..7475d15ed209 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1765,17 +1765,20 @@ extern bool inode_owner_or_capable(struct user_namespace *user_ns, const struct
/*
* VFS helper functions..
*/
-extern int vfs_create(struct inode *, struct dentry *, umode_t, bool);
-extern int vfs_mkdir(struct inode *, struct dentry *, umode_t);
-extern int vfs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
-extern int vfs_symlink(struct inode *, struct dentry *, const char *);
-extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct inode **);
-extern int vfs_rmdir(struct inode *, struct dentry *);
-extern int vfs_unlink(struct inode *, struct dentry *, struct inode **);
+extern int vfs_create(struct user_namespace *, struct inode *, struct dentry *, umode_t, bool);
+extern int vfs_mkdir(struct user_namespace *, struct inode *, struct dentry *, umode_t);
+extern int vfs_mknod(struct user_namespace *, struct inode *, struct dentry *, umode_t, dev_t);
+extern int vfs_symlink(struct user_namespace *, struct inode *, struct dentry *, const char *);
+extern int vfs_link(struct dentry *, struct user_namespace *, struct inode *,
+ struct dentry *, struct inode **);
+extern int vfs_rmdir(struct user_namespace *, struct inode *, struct dentry *);
+extern int vfs_unlink(struct user_namespace *, struct inode *, struct dentry *, struct inode **);
struct renamedata {
+ struct user_namespace *old_user_ns;
struct inode *old_dir;
struct dentry *old_dentry;
+ struct user_namespace *new_user_ns;
struct inode *new_dir;
struct dentry *new_dentry;
struct inode **delegated_inode;
@@ -1784,12 +1787,14 @@ struct renamedata {
extern int vfs_rename(struct renamedata *);
-static inline int vfs_whiteout(struct inode *dir, struct dentry *dentry)
+static inline int vfs_whiteout(struct user_namespace *user_ns,
+ struct inode *dir, struct dentry *dentry)
{
- return vfs_mknod(dir, dentry, S_IFCHR | WHITEOUT_MODE, WHITEOUT_DEV);
+ return vfs_mknod(user_ns, dir, dentry, S_IFCHR | WHITEOUT_MODE, WHITEOUT_DEV);
}
-extern struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode,
+extern struct dentry *vfs_tmpfile(struct user_namespace *user_ns,
+ struct dentry *dentry, umode_t mode,
int open_flag);
int vfs_mkobj(struct dentry *, umode_t,
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index 693f01fe1216..8b8c300854db 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -965,7 +965,7 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
err = -ENOENT;
} else {
ihold(inode);
- err = vfs_unlink(d_inode(dentry->d_parent), dentry, NULL);
+ err = vfs_unlink(&init_user_ns, d_inode(dentry->d_parent), dentry, NULL);
}
dput(dentry);
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index f568526d4a02..b4987805e5e5 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -996,7 +996,7 @@ static int unix_mknod(const char *sun_path, umode_t mode, struct path *res)
*/
err = security_path_mknod(&path, dentry, mode, 0);
if (!err) {
- err = vfs_mknod(d_inode(path.dentry), dentry, mode, 0);
+ err = vfs_mknod(&init_user_ns, d_inode(path.dentry), dentry, mode, 0);
if (!err) {
res->mnt = mntget(path.mnt);
res->dentry = dget(dentry);
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 19/38] open: handle idmapped mounts in do_truncate()
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (17 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 18/38] namei: prepare for idmapped mounts Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 20/38] open: handle idmapped mounts Christian Brauner
` (17 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
When truncating files the vfs will verify that the caller is privileged over the
inode. Extend it to handle idmapped mounts. If the inode is accessed through an
idmapped mount it is mapped according to the mount's user namespace. Afterwards
the permissions checks are identical to non-idmapped mounts. If the initial user
namespace is passed nothing changes so non-idmapped mounts will see identical
behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
fs/coredump.c | 12 +++++++++---
fs/inode.c | 13 +++++++++----
fs/namei.c | 6 +++---
fs/open.c | 21 +++++++++++++--------
include/linux/fs.h | 4 ++--
5 files changed, 36 insertions(+), 20 deletions(-)
diff --git a/fs/coredump.c b/fs/coredump.c
index 0cd9056d79cc..25beac7230ff 100644
--- a/fs/coredump.c
+++ b/fs/coredump.c
@@ -703,6 +703,7 @@ void do_coredump(const kernel_siginfo_t *siginfo)
goto close_fail;
}
} else {
+ struct user_namespace *user_ns;
struct inode *inode;
int open_flags = O_CREAT | O_RDWR | O_NOFOLLOW |
O_LARGEFILE | O_EXCL;
@@ -786,7 +787,8 @@ void do_coredump(const kernel_siginfo_t *siginfo)
goto close_fail;
if (!(cprm.file->f_mode & FMODE_CAN_WRITE))
goto close_fail;
- if (do_truncate(cprm.file->f_path.dentry, 0, 0, cprm.file))
+ user_ns = mnt_user_ns(cprm.file->f_path.mnt);
+ if (do_truncate(user_ns, cprm.file->f_path.dentry, 0, 0, cprm.file))
goto close_fail;
}
@@ -931,8 +933,12 @@ void dump_truncate(struct coredump_params *cprm)
if (file->f_op->llseek && file->f_op->llseek != no_llseek) {
offset = file->f_op->llseek(file, 0, SEEK_CUR);
- if (i_size_read(file->f_mapping->host) < offset)
- do_truncate(file->f_path.dentry, offset, 0, file);
+ if (i_size_read(file->f_mapping->host) < offset) {
+ struct user_namespace *user_ns;
+
+ user_ns = mnt_user_ns(file->f_path.mnt);
+ do_truncate(user_ns, file->f_path.dentry, offset, 0, file);
+ }
}
}
EXPORT_SYMBOL(dump_truncate);
diff --git a/fs/inode.c b/fs/inode.c
index 75c64f003c45..0ccdd673636d 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1904,7 +1904,8 @@ int dentry_needs_remove_privs(struct dentry *dentry)
return mask;
}
-static int __remove_privs(struct dentry *dentry, int kill)
+static int __remove_privs(struct user_namespace *user_ns, struct dentry *dentry,
+ int kill)
{
struct iattr newattrs;
@@ -1913,7 +1914,7 @@ static int __remove_privs(struct dentry *dentry, int kill)
* Note we call this on write, so notify_change will not
* encounter any conflicting delegations:
*/
- return notify_change(&init_user_ns, dentry, &newattrs, NULL);
+ return notify_change(user_ns, dentry, &newattrs, NULL);
}
/*
@@ -1939,8 +1940,12 @@ int file_remove_privs(struct file *file)
kill = dentry_needs_remove_privs(dentry);
if (kill < 0)
return kill;
- if (kill)
- error = __remove_privs(dentry, kill);
+ if (kill) {
+ struct user_namespace *user_ns;
+
+ user_ns = mnt_user_ns(file->f_path.mnt);
+ error = __remove_privs(user_ns, dentry, kill);
+ }
if (!error)
inode_has_no_xattr(inode);
diff --git a/fs/namei.c b/fs/namei.c
index b91bf923d22c..5601b6680d4c 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2940,9 +2940,9 @@ static int handle_truncate(struct file *filp)
if (!error)
error = security_path_truncate(path);
if (!error) {
- error = do_truncate(path->dentry, 0,
- ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
- filp);
+ error = do_truncate(mnt_user_ns(filp->f_path.mnt),
+ path->dentry, 0,
+ ATTR_MTIME | ATTR_CTIME | ATTR_OPEN, filp);
}
put_write_access(inode);
return error;
diff --git a/fs/open.c b/fs/open.c
index 2dc94689a7dc..137dcc52d2f8 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -35,8 +35,8 @@
#include "internal.h"
-int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
- struct file *filp)
+int do_truncate(struct user_namespace *user_ns, struct dentry *dentry,
+ loff_t length, unsigned int time_attrs, struct file *filp)
{
int ret;
struct iattr newattrs;
@@ -61,13 +61,14 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
inode_lock(dentry->d_inode);
/* Note any delegations or leases have already been broken: */
- ret = notify_change(&init_user_ns, dentry, &newattrs, NULL);
+ ret = notify_change(user_ns, dentry, &newattrs, NULL);
inode_unlock(dentry->d_inode);
return ret;
}
long vfs_truncate(const struct path *path, loff_t length)
{
+ struct user_namespace *user_ns;
struct inode *inode;
long error;
@@ -83,7 +84,8 @@ long vfs_truncate(const struct path *path, loff_t length)
if (error)
goto out;
- error = inode_permission(&init_user_ns, inode, MAY_WRITE);
+ user_ns = mnt_user_ns(path->mnt);
+ error = inode_permission(user_ns, inode, MAY_WRITE);
if (error)
goto mnt_drop_write_and_out;
@@ -107,7 +109,7 @@ long vfs_truncate(const struct path *path, loff_t length)
if (!error)
error = security_path_truncate(path);
if (!error)
- error = do_truncate(path->dentry, length, 0, NULL);
+ error = do_truncate(user_ns, path->dentry, length, 0, NULL);
put_write_and_out:
put_write_access(inode);
@@ -186,13 +188,16 @@ long do_sys_ftruncate(unsigned int fd, loff_t length, int small)
/* Check IS_APPEND on real upper inode */
if (IS_APPEND(file_inode(f.file)))
goto out_putf;
-
sb_start_write(inode->i_sb);
error = locks_verify_truncate(inode, f.file, length);
if (!error)
error = security_path_truncate(&f.file->f_path);
- if (!error)
- error = do_truncate(dentry, length, ATTR_MTIME|ATTR_CTIME, f.file);
+ if (!error) {
+ struct user_namespace *user_ns;
+
+ user_ns = mnt_user_ns(f.file->f_path.mnt);
+ error = do_truncate(user_ns, dentry, length, ATTR_MTIME | ATTR_CTIME, f.file);
+ }
sb_end_write(inode->i_sb);
out_putf:
fdput(f);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 7475d15ed209..78909e4071aa 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2581,8 +2581,8 @@ struct filename {
static_assert(offsetof(struct filename, iname) % sizeof(long) == 0);
extern long vfs_truncate(const struct path *, loff_t);
-extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
- struct file *filp);
+extern int do_truncate(struct user_namespace *, struct dentry *, loff_t start,
+ unsigned int time_attrs, struct file *filp);
extern int vfs_fallocate(struct file *file, int mode, loff_t offset,
loff_t len);
extern long do_sys_open(int dfd, const char __user *filename, int flags,
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 20/38] open: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (18 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 19/38] open: handle idmapped mounts in do_truncate() Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 21/38] af_unix: " Christian Brauner
` (16 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
For core file operations such as changing directories or chrooting,
determining file access, changing mode or ownership the vfs will verify
that the caller is privileged over the inode. Extend the various helpers to
handle idmapped mounts. If the inode is accessed through an idmapped mount
it is mapped according to the mount's user namespace. Afterwards the
permissions checks are identical to non-idmapped mounts. When changing file
ownership we need to map the uid and gid from the mount's user namespace.
If the initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
- David Howells <dhowells@redhat.com>:
- Remove mnt_idmapped() check after removing mnt_idmapped() helper in earlier
patches.
---
fs/open.c | 29 ++++++++++++++++++++++-------
1 file changed, 22 insertions(+), 7 deletions(-)
diff --git a/fs/open.c b/fs/open.c
index 137dcc52d2f8..679de603b3c1 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -401,6 +401,7 @@ static const struct cred *access_override_creds(void)
static long do_faccessat(int dfd, const char __user *filename, int mode, int flags)
{
+ struct user_namespace *user_ns;
struct path path;
struct inode *inode;
int res;
@@ -441,7 +442,8 @@ static long do_faccessat(int dfd, const char __user *filename, int mode, int fla
goto out_path_release;
}
- res = inode_permission(&init_user_ns, inode, mode | MAY_ACCESS);
+ user_ns = mnt_user_ns(path.mnt);
+ res = inode_permission(user_ns, inode, mode | MAY_ACCESS);
/* SuS v2 requires we report a read only fs too */
if (res || !(mode & S_IWOTH) || special_file(inode->i_mode))
goto out_path_release;
@@ -489,6 +491,7 @@ SYSCALL_DEFINE2(access, const char __user *, filename, int, mode)
SYSCALL_DEFINE1(chdir, const char __user *, filename)
{
+ struct user_namespace *user_ns;
struct path path;
int error;
unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
@@ -497,7 +500,8 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename)
if (error)
goto out;
- error = inode_permission(&init_user_ns, path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+ user_ns = mnt_user_ns(path.mnt);
+ error = inode_permission(user_ns, path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
if (error)
goto dput_and_out;
@@ -515,6 +519,7 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename)
SYSCALL_DEFINE1(fchdir, unsigned int, fd)
{
+ struct user_namespace *user_ns;
struct fd f = fdget_raw(fd);
int error;
@@ -526,7 +531,8 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd)
if (!d_can_lookup(f.file->f_path.dentry))
goto out_putf;
- error = inode_permission(&init_user_ns, file_inode(f.file), MAY_EXEC | MAY_CHDIR);
+ user_ns = mnt_user_ns(f.file->f_path.mnt);
+ error = inode_permission(user_ns, file_inode(f.file), MAY_EXEC | MAY_CHDIR);
if (!error)
set_fs_pwd(current->fs, &f.file->f_path);
out_putf:
@@ -537,6 +543,7 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd)
SYSCALL_DEFINE1(chroot, const char __user *, filename)
{
+ struct user_namespace *user_ns;
struct path path;
int error;
unsigned int lookup_flags = LOOKUP_FOLLOW | LOOKUP_DIRECTORY;
@@ -545,7 +552,8 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename)
if (error)
goto out;
- error = inode_permission(&init_user_ns, path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
+ user_ns = mnt_user_ns(path.mnt);
+ error = inode_permission(user_ns, path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
if (error)
goto dput_and_out;
@@ -570,6 +578,7 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename)
int chmod_common(const struct path *path, umode_t mode)
{
+ struct user_namespace *user_ns;
struct inode *inode = path->dentry->d_inode;
struct inode *delegated_inode = NULL;
struct iattr newattrs;
@@ -585,7 +594,8 @@ int chmod_common(const struct path *path, umode_t mode)
goto out_unlock;
newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
- error = notify_change(&init_user_ns, path->dentry, &newattrs, &delegated_inode);
+ user_ns = mnt_user_ns(path->mnt);
+ error = notify_change(user_ns, path->dentry, &newattrs, &delegated_inode);
out_unlock:
inode_unlock(inode);
if (delegated_inode) {
@@ -646,6 +656,7 @@ SYSCALL_DEFINE2(chmod, const char __user *, filename, umode_t, mode)
int chown_common(const struct path *path, uid_t user, gid_t group)
{
+ struct user_namespace *user_ns;
struct inode *inode = path->dentry->d_inode;
struct inode *delegated_inode = NULL;
int error;
@@ -656,6 +667,10 @@ int chown_common(const struct path *path, uid_t user, gid_t group)
uid = make_kuid(current_user_ns(), user);
gid = make_kgid(current_user_ns(), group);
+ user_ns = mnt_user_ns(path->mnt);
+ uid = kuid_from_mnt(user_ns, uid);
+ gid = kgid_from_mnt(user_ns, gid);
+
retry_deleg:
newattrs.ia_valid = ATTR_CTIME;
if (user != (uid_t) -1) {
@@ -676,7 +691,7 @@ int chown_common(const struct path *path, uid_t user, gid_t group)
inode_lock(inode);
error = security_path_chown(path, uid, gid);
if (!error)
- error = notify_change(&init_user_ns, path->dentry, &newattrs, &delegated_inode);
+ error = notify_change(user_ns, path->dentry, &newattrs, &delegated_inode);
inode_unlock(inode);
if (delegated_inode) {
error = break_deleg_wait(&delegated_inode);
@@ -1133,7 +1148,7 @@ struct file *filp_open(const char *filename, int flags, umode_t mode)
{
struct filename *name = getname_kernel(filename);
struct file *file = ERR_CAST(name);
-
+
if (!IS_ERR(name)) {
file = file_open_name(name, flags, mode);
putname(name);
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 21/38] af_unix: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (19 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 20/38] open: handle idmapped mounts Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 22/38] utimes: " Christian Brauner
` (15 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
When binding a non-abstract AF_UNIX socket it will gain a representation in the
filesystem. Enable the socket infrastructure to handle idmapped mounts by
passing down the user namespace of the mount the socket will be created from. If
the initial user namespace is passed nothing changes so non-idmapped mounts will
see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
net/unix/af_unix.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index b4987805e5e5..4be33240e9cc 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -996,7 +996,7 @@ static int unix_mknod(const char *sun_path, umode_t mode, struct path *res)
*/
err = security_path_mknod(&path, dentry, mode, 0);
if (!err) {
- err = vfs_mknod(&init_user_ns, d_inode(path.dentry), dentry, mode, 0);
+ err = vfs_mknod(mnt_user_ns(path.mnt), d_inode(path.dentry), dentry, mode, 0);
if (!err) {
res->mnt = mntget(path.mnt);
res->dentry = dget(dentry);
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 22/38] utimes: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (20 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 21/38] af_unix: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 23/38] fcntl: " Christian Brauner
` (14 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
Enable the vfs_utimes() helper to handle idmapped mounts by passing down
the mount's user namespace. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
fs/utimes.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/utimes.c b/fs/utimes.c
index 1a4130bee157..ead17d623aaa 100644
--- a/fs/utimes.c
+++ b/fs/utimes.c
@@ -22,6 +22,7 @@ int vfs_utimes(const struct path *path, struct timespec64 *times)
struct iattr newattrs;
struct inode *inode = path->dentry->d_inode;
struct inode *delegated_inode = NULL;
+ struct user_namespace *user_ns;
if (times) {
if (!nsec_valid(times[0].tv_nsec) ||
@@ -61,8 +62,9 @@ int vfs_utimes(const struct path *path, struct timespec64 *times)
newattrs.ia_valid |= ATTR_TOUCH;
}
retry_deleg:
+ user_ns = mnt_user_ns(path->mnt);
inode_lock(inode);
- error = notify_change(&init_user_ns, path->dentry, &newattrs, &delegated_inode);
+ error = notify_change(user_ns, path->dentry, &newattrs, &delegated_inode);
inode_unlock(inode);
if (delegated_inode) {
error = break_deleg_wait(&delegated_inode);
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 23/38] fcntl: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (21 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 22/38] utimes: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 24/38] notify: " Christian Brauner
` (13 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
Enable the setfl() helper to handle idmapped mounts by passing down the
mount's user namespace. If the initial user namespace is passed nothing changes
so non-idmapped mounts will see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
patch introduced
/* v3 */
unchanged
---
fs/fcntl.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/fs/fcntl.c b/fs/fcntl.c
index df091d435603..ed330fa91438 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -25,6 +25,7 @@
#include <linux/user_namespace.h>
#include <linux/memfd.h>
#include <linux/compat.h>
+#include <linux/mount.h>
#include <linux/poll.h>
#include <asm/siginfo.h>
@@ -46,7 +47,7 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
/* O_NOATIME can only be set by the owner or superuser */
if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME))
- if (!inode_owner_or_capable(&init_user_ns, inode))
+ if (!inode_owner_or_capable(mnt_user_ns(filp->f_path.mnt), inode))
return -EPERM;
/* required for strict SunOS emulation */
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 24/38] notify: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (22 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 23/38] fcntl: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 25/38] init: " Christian Brauner
` (12 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
Enable notify implementations to handle idmapped mounts by passing down the
mount's user namespace. If the initial user namespace is passed nothing changes
so non-idmapped mounts will see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
patch introduced
/* v3 */
unchanged
---
fs/notify/fanotify/fanotify_user.c | 2 +-
fs/notify/inotify/inotify_user.c | 3 ++-
2 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index de4d01bb1d8d..e3b2cb6a9d81 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -702,7 +702,7 @@ static int fanotify_find_path(int dfd, const char __user *filename,
}
/* you can only watch an inode if you have read permissions on it */
- ret = inode_permission(&init_user_ns, path->dentry->d_inode, MAY_READ);
+ ret = inode_permission(mnt_user_ns(path->mnt), path->dentry->d_inode, MAY_READ);
if (ret) {
path_put(path);
goto out;
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index e995fd4e4e53..f39f5b81f2b3 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -31,6 +31,7 @@
#include <linux/wait.h>
#include <linux/memcontrol.h>
#include <linux/security.h>
+#include <linux/mount.h>
#include "inotify.h"
#include "../fdinfo.h"
@@ -343,7 +344,7 @@ static int inotify_find_inode(const char __user *dirname, struct path *path,
if (error)
return error;
/* you can only watch an inode if you have read permissions on it */
- error = inode_permission(&init_user_ns, path->dentry->d_inode, MAY_READ);
+ error = inode_permission(mnt_user_ns(path->mnt), path->dentry->d_inode, MAY_READ);
if (error) {
path_put(path);
return error;
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 25/38] init: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (23 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 24/38] notify: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 26/38] ioctl: " Christian Brauner
` (11 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
Enable the init helpers to handle idmapped mounts by passing down the mount's
user namespace. If the initial user namespace is passed nothing changes so
non-idmapped mounts will see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
patch introduced
/* v3 */
unchanged
---
fs/init.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/fs/init.c b/fs/init.c
index 76f493600030..41adfee75763 100644
--- a/fs/init.c
+++ b/fs/init.c
@@ -49,7 +49,7 @@ int __init init_chdir(const char *filename)
error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
if (error)
return error;
- error = inode_permission(&init_user_ns, path.dentry->d_inode,
+ error = inode_permission(mnt_user_ns(path.mnt), path.dentry->d_inode,
MAY_EXEC | MAY_CHDIR);
if (!error)
set_fs_pwd(current->fs, &path);
@@ -65,7 +65,7 @@ int __init init_chroot(const char *filename)
error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
if (error)
return error;
- error = inode_permission(&init_user_ns, path.dentry->d_inode,
+ error = inode_permission(mnt_user_ns(path.mnt), path.dentry->d_inode,
MAY_EXEC | MAY_CHDIR);
if (error)
goto dput_and_out;
@@ -120,7 +120,7 @@ int __init init_eaccess(const char *filename)
error = kern_path(filename, LOOKUP_FOLLOW, &path);
if (error)
return error;
- error = inode_permission(&init_user_ns, d_inode(path.dentry),
+ error = inode_permission(mnt_user_ns(path.mnt), d_inode(path.dentry),
MAY_ACCESS);
path_put(&path);
return error;
@@ -160,8 +160,8 @@ int __init init_mknod(const char *filename, umode_t mode, unsigned int dev)
mode &= ~current_umask();
error = security_path_mknod(&path, dentry, mode, dev);
if (!error)
- error = vfs_mknod(&init_user_ns, path.dentry->d_inode, dentry,
- mode, new_decode_dev(dev));
+ error = vfs_mknod(mnt_user_ns(path.mnt), path.dentry->d_inode,
+ dentry, mode, new_decode_dev(dev));
done_path_create(&path, dentry);
return error;
}
@@ -190,7 +190,7 @@ int __init init_link(const char *oldname, const char *newname)
error = security_path_link(old_path.dentry, &new_path, new_dentry);
if (error)
goto out_dput;
- error = vfs_link(old_path.dentry, &init_user_ns,
+ error = vfs_link(old_path.dentry, mnt_user_ns(new_path.mnt),
new_path.dentry->d_inode, new_dentry, NULL);
out_dput:
done_path_create(&new_path, new_dentry);
@@ -210,7 +210,8 @@ int __init init_symlink(const char *oldname, const char *newname)
return PTR_ERR(dentry);
error = security_path_symlink(&path, dentry, oldname);
if (!error)
- error = vfs_symlink(&init_user_ns, path.dentry->d_inode, dentry, oldname);
+ error = vfs_symlink(mnt_user_ns(path.mnt), path.dentry->d_inode,
+ dentry, oldname);
done_path_create(&path, dentry);
return error;
}
@@ -233,7 +234,8 @@ int __init init_mkdir(const char *pathname, umode_t mode)
mode &= ~current_umask();
error = security_path_mkdir(&path, dentry, mode);
if (!error)
- error = vfs_mkdir(&init_user_ns, path.dentry->d_inode, dentry, mode);
+ error = vfs_mkdir(mnt_user_ns(path.mnt), path.dentry->d_inode,
+ dentry, mode);
done_path_create(&path, dentry);
return error;
}
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 26/38] ioctl: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (24 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 25/38] init: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 27/38] would_dump: " Christian Brauner
` (10 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
Enable generic ioctls to handle idmapped mounts by passing down the mount's user
namespace. If the initial user namespace is passed nothing changes so
non-idmapped mounts will see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
patch introduced
/* v3 */
unchanged
---
fs/remap_range.c | 7 +++++--
fs/verity/enable.c | 2 +-
2 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/fs/remap_range.c b/fs/remap_range.c
index 9e5b27641756..fe7f07228462 100644
--- a/fs/remap_range.c
+++ b/fs/remap_range.c
@@ -432,13 +432,16 @@ EXPORT_SYMBOL(vfs_clone_file_range);
/* Check whether we are allowed to dedupe the destination file */
static bool allow_file_dedupe(struct file *file)
{
+ struct user_namespace *user_ns = mnt_user_ns(file->f_path.mnt);
+ struct inode *inode = file_inode(file);
+
if (capable(CAP_SYS_ADMIN))
return true;
if (file->f_mode & FMODE_WRITE)
return true;
- if (uid_eq(current_fsuid(), file_inode(file)->i_uid))
+ if (uid_eq(current_fsuid(), i_uid_into_mnt(user_ns, inode)))
return true;
- if (!inode_permission(&init_user_ns, file_inode(file), MAY_WRITE))
+ if (!inode_permission(user_ns, inode, MAY_WRITE))
return true;
return false;
}
diff --git a/fs/verity/enable.c b/fs/verity/enable.c
index 7449ef0050f4..8b9ea0f0850f 100644
--- a/fs/verity/enable.c
+++ b/fs/verity/enable.c
@@ -369,7 +369,7 @@ int fsverity_ioctl_enable(struct file *filp, const void __user *uarg)
* has verity enabled, and to stabilize the data being hashed.
*/
- err = inode_permission(&init_user_ns, inode, MAY_WRITE);
+ err = inode_permission(mnt_user_ns(filp->f_path.mnt), inode, MAY_WRITE);
if (err)
return err;
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 27/38] would_dump: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (25 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 26/38] ioctl: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 28/38] exec: " Christian Brauner
` (9 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
When determining whether or not to create a coredump the vfs will verify that
the caller is privileged over the inode. Make the would_dump() helper handle
idmapped mounts by passing down the mount's user namespace of the exec file. If
the initial user namespace is passed nothing changes so non-idmapped mounts will
see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
fs/exec.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/exec.c b/fs/exec.c
index b499a1a03934..10c06fdf78a7 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1391,14 +1391,15 @@ EXPORT_SYMBOL(begin_new_exec);
void would_dump(struct linux_binprm *bprm, struct file *file)
{
struct inode *inode = file_inode(file);
- if (inode_permission(&init_user_ns, inode, MAY_READ) < 0) {
+ struct user_namespace *ns = mnt_user_ns(file->f_path.mnt);
+ if (inode_permission(ns, inode, MAY_READ) < 0) {
struct user_namespace *old, *user_ns;
bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
/* Ensure mm->user_ns contains the executable */
user_ns = old = bprm->mm->user_ns;
while ((user_ns != &init_user_ns) &&
- !privileged_wrt_inode_uidgid(user_ns, &init_user_ns, inode))
+ !privileged_wrt_inode_uidgid(user_ns, ns, inode))
user_ns = user_ns->parent;
if (old != user_ns) {
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 28/38] exec: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (26 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 27/38] would_dump: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 30/38] apparmor: " Christian Brauner
` (8 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
When executing a setuid binary the kernel will verify in bprm_fill_uid() that
the inode has a mapping in the caller's user namespace before setting the
callers uid and gid. Let bprm_fill_uid() handle idmapped mounts. If the inode
is accessed through an idmapped mount it is mapped according to the mount's
user namespace. Afterwards the checks are identical to non-idmapped mounts. If
the initial user namespace is passed nothing changes so non-idmapped mounts will
see identical behavior as before.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
fs/exec.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/fs/exec.c b/fs/exec.c
index 10c06fdf78a7..7d6d3dd17e84 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1567,6 +1567,7 @@ static void check_unsafe_exec(struct linux_binprm *bprm)
static void bprm_fill_uid(struct linux_binprm *bprm, struct file *file)
{
/* Handle suid and sgid on files */
+ struct user_namespace *user_ns;
struct inode *inode;
unsigned int mode;
kuid_t uid;
@@ -1583,13 +1584,15 @@ static void bprm_fill_uid(struct linux_binprm *bprm, struct file *file)
if (!(mode & (S_ISUID|S_ISGID)))
return;
+ user_ns = mnt_user_ns(file->f_path.mnt);
+
/* Be careful if suid/sgid is set */
inode_lock(inode);
/* reload atomically mode/uid/gid now that lock held */
mode = inode->i_mode;
- uid = inode->i_uid;
- gid = inode->i_gid;
+ uid = i_uid_into_mnt(user_ns, inode);
+ gid = i_gid_into_mnt(user_ns, inode);
inode_unlock(inode);
/* We ignore suid/sgid if there are no mappings for them in the ns */
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 30/38] apparmor: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (27 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 28/38] exec: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 31/38] ima: " Christian Brauner
` (7 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner
The i_uid and i_gid are only ever used when logging for AppArmor. This is
already broken in a bunch of places where the global root id is reported
instead of the i_uid or i_gid of the file. Nonetheless, be kind and log the
mapped inode if we're coming from an idmapped mount. If the initial user
namespace is passed nothing changes so non-idmapped mounts will see identical
behavior as before.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
security/apparmor/domain.c | 9 ++++++---
security/apparmor/file.c | 5 ++++-
security/apparmor/lsm.c | 12 ++++++++----
3 files changed, 18 insertions(+), 8 deletions(-)
diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c
index 16f184bc48de..4f997dba4573 100644
--- a/security/apparmor/domain.c
+++ b/security/apparmor/domain.c
@@ -10,12 +10,14 @@
#include <linux/errno.h>
#include <linux/fdtable.h>
+#include <linux/fs.h>
#include <linux/file.h>
#include <linux/mount.h>
#include <linux/syscalls.h>
#include <linux/tracehook.h>
#include <linux/personality.h>
#include <linux/xattr.h>
+#include <linux/user_namespace.h>
#include "include/audit.h"
#include "include/apparmorfs.h"
@@ -858,8 +860,10 @@ int apparmor_bprm_creds_for_exec(struct linux_binprm *bprm)
const char *info = NULL;
int error = 0;
bool unsafe = false;
+ struct user_namespace *user_ns = mnt_user_ns(bprm->file->f_path.mnt);
+ kuid_t i_uid = i_uid_into_mnt(user_ns, file_inode(bprm->file));
struct path_cond cond = {
- file_inode(bprm->file)->i_uid,
+ i_uid,
file_inode(bprm->file)->i_mode
};
@@ -967,8 +971,7 @@ int apparmor_bprm_creds_for_exec(struct linux_binprm *bprm)
error = fn_for_each(label, profile,
aa_audit_file(profile, &nullperms, OP_EXEC, MAY_EXEC,
bprm->filename, NULL, new,
- file_inode(bprm->file)->i_uid, info,
- error));
+ i_uid, info, error));
aa_put_label(new);
goto done;
}
diff --git a/security/apparmor/file.c b/security/apparmor/file.c
index 92acf9a49405..d6d9e71f1900 100644
--- a/security/apparmor/file.c
+++ b/security/apparmor/file.c
@@ -11,6 +11,8 @@
#include <linux/tty.h>
#include <linux/fdtable.h>
#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/mount.h>
#include "include/apparmor.h"
#include "include/audit.h"
@@ -508,8 +510,9 @@ static int __file_path_perm(const char *op, struct aa_label *label,
{
struct aa_profile *profile;
struct aa_perms perms = {};
+ struct user_namespace *user_ns = mnt_user_ns(file->f_path.mnt);
struct path_cond cond = {
- .uid = file_inode(file)->i_uid,
+ .uid = i_uid_into_mnt(user_ns, file_inode(file)),
.mode = file_inode(file)->i_mode
};
char *buffer;
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index ffeaee5ed968..ece9afc3994f 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -224,7 +224,8 @@ static int common_perm(const char *op, const struct path *path, u32 mask,
*/
static int common_perm_cond(const char *op, const struct path *path, u32 mask)
{
- struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
+ struct user_namespace *user_ns = mnt_user_ns(path->mnt);
+ struct path_cond cond = { i_uid_into_mnt(user_ns, d_backing_inode(path->dentry)),
d_backing_inode(path->dentry)->i_mode
};
@@ -266,12 +267,13 @@ static int common_perm_rm(const char *op, const struct path *dir,
struct dentry *dentry, u32 mask)
{
struct inode *inode = d_backing_inode(dentry);
+ struct user_namespace *user_ns = mnt_user_ns(dir->mnt);
struct path_cond cond = { };
if (!inode || !path_mediated_fs(dentry))
return 0;
- cond.uid = inode->i_uid;
+ cond.uid = i_uid_into_mnt(user_ns, inode);
cond.mode = inode->i_mode;
return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
@@ -361,11 +363,12 @@ static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_d
label = begin_current_label_crit_section();
if (!unconfined(label)) {
+ struct user_namespace *user_ns = mnt_user_ns(old_dir->mnt);
struct path old_path = { .mnt = old_dir->mnt,
.dentry = old_dentry };
struct path new_path = { .mnt = new_dir->mnt,
.dentry = new_dentry };
- struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
+ struct path_cond cond = { i_uid_into_mnt(user_ns, d_backing_inode(old_dentry)),
d_backing_inode(old_dentry)->i_mode
};
@@ -420,8 +423,9 @@ static int apparmor_file_open(struct file *file)
label = aa_get_newest_cred_label(file->f_cred);
if (!unconfined(label)) {
+ struct user_namespace *user_ns = mnt_user_ns(file->f_path.mnt);
struct inode *inode = file_inode(file);
- struct path_cond cond = { inode->i_uid, inode->i_mode };
+ struct path_cond cond = { i_uid_into_mnt(user_ns, inode), inode->i_mode };
error = aa_path_perm(OP_OPEN, label, &file->f_path, 0,
aa_map_file_to_perms(file), &cond);
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 31/38] ima: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (28 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 30/38] apparmor: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 32/38] fat: " Christian Brauner
` (6 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner
IMA does sometimes access the inode's i_uid and compares it against the rules'
fowner. Enable IMA to handle idmapped mounts by passing down the mount's user
namespace. We simply make use of the helpers we introduced before. If the
initial user namespace is passed nothing changes so non-idmapped mounts will see
identical behavior as before.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
fs/attr.c | 2 +-
fs/namei.c | 4 +--
include/linux/ima.h | 15 ++++++-----
security/integrity/ima/ima.h | 19 ++++++++-----
security/integrity/ima/ima_api.c | 10 ++++---
security/integrity/ima/ima_appraise.c | 14 +++++-----
security/integrity/ima/ima_asymmetric_keys.c | 2 +-
security/integrity/ima/ima_main.c | 28 ++++++++++++--------
security/integrity/ima/ima_policy.c | 17 ++++++------
security/integrity/ima/ima_queue_keys.c | 2 +-
10 files changed, 66 insertions(+), 47 deletions(-)
diff --git a/fs/attr.c b/fs/attr.c
index fb78896a1ce5..c4c442d4b17d 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -357,7 +357,7 @@ int notify_change(struct user_namespace *user_ns, struct dentry *dentry,
if (!error) {
fsnotify_change(dentry, ia_valid);
- ima_inode_post_setattr(dentry);
+ ima_inode_post_setattr(user_ns, dentry);
evm_inode_post_setattr(dentry, ia_valid);
}
diff --git a/fs/namei.c b/fs/namei.c
index 1d6a0da8bf81..6e564147ead8 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3333,7 +3333,7 @@ struct dentry *vfs_tmpfile(struct user_namespace *user_ns,
inode->i_state |= I_LINKABLE;
spin_unlock(&inode->i_lock);
}
- ima_post_create_tmpfile(inode);
+ ima_post_create_tmpfile(user_ns, inode);
return child;
out_err:
@@ -3645,7 +3645,7 @@ static long do_mknodat(int dfd, const char __user *filename, umode_t mode,
error = vfs_create(user_ns, path.dentry->d_inode,
dentry, mode, true);
if (!error)
- ima_post_path_mknod(dentry);
+ ima_post_path_mknod(user_ns, dentry);
break;
case S_IFCHR: case S_IFBLK:
error = vfs_mknod(user_ns, path.dentry->d_inode, dentry,
diff --git a/include/linux/ima.h b/include/linux/ima.h
index 8fa7bcfb2da2..c3e3c260ad40 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h
@@ -16,7 +16,7 @@ struct linux_binprm;
#ifdef CONFIG_IMA
extern int ima_bprm_check(struct linux_binprm *bprm);
extern int ima_file_check(struct file *file, int mask);
-extern void ima_post_create_tmpfile(struct inode *inode);
+extern void ima_post_create_tmpfile(struct user_namespace *user_ns, struct inode *inode);
extern void ima_file_free(struct file *file);
extern int ima_file_mmap(struct file *file, unsigned long prot);
extern int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot);
@@ -27,7 +27,8 @@ extern int ima_read_file(struct file *file, enum kernel_read_file_id id,
bool contents);
extern int ima_post_read_file(struct file *file, void *buf, loff_t size,
enum kernel_read_file_id id);
-extern void ima_post_path_mknod(struct dentry *dentry);
+extern void ima_post_path_mknod(struct user_namespace *user_ns,
+ struct dentry *dentry);
extern int ima_file_hash(struct file *file, char *buf, size_t buf_size);
extern void ima_kexec_cmdline(int kernel_fd, const void *buf, int size);
@@ -61,7 +62,8 @@ static inline int ima_file_check(struct file *file, int mask)
return 0;
}
-static inline void ima_post_create_tmpfile(struct inode *inode)
+static inline void ima_post_create_tmpfile(struct user_namespace *user_ns,
+ struct inode *inode)
{
}
@@ -105,7 +107,8 @@ static inline int ima_post_read_file(struct file *file, void *buf, loff_t size,
return 0;
}
-static inline void ima_post_path_mknod(struct dentry *dentry)
+static inline void ima_post_path_mknod(struct user_namespace *user_ns,
+ struct dentry *dentry)
{
return;
}
@@ -141,7 +144,7 @@ static inline void ima_post_key_create_or_update(struct key *keyring,
#ifdef CONFIG_IMA_APPRAISE
extern bool is_ima_appraise_enabled(void);
-extern void ima_inode_post_setattr(struct dentry *dentry);
+extern void ima_inode_post_setattr(struct user_namespace *user_ns, struct dentry *dentry);
extern int ima_inode_setxattr(struct dentry *dentry, const char *xattr_name,
const void *xattr_value, size_t xattr_value_len);
extern int ima_inode_removexattr(struct dentry *dentry, const char *xattr_name);
@@ -151,7 +154,7 @@ static inline bool is_ima_appraise_enabled(void)
return 0;
}
-static inline void ima_inode_post_setattr(struct dentry *dentry)
+static inline void ima_inode_post_setattr(struct user_namespace *user_ns, struct dentry *dentry)
{
return;
}
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 6ebefec616e4..54da7b1a2faa 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -252,8 +252,9 @@ static inline void ima_process_queued_keys(void) {}
#endif /* CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS */
/* LIM API function definitions */
-int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
- int mask, enum ima_hooks func, int *pcr,
+int ima_get_action(struct user_namespace *user_ns, struct inode *inode,
+ const struct cred *cred, u32 secid, int mask,
+ enum ima_hooks func, int *pcr,
struct ima_template_desc **template_desc,
const char *keyring);
int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
@@ -265,7 +266,8 @@ void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
struct evm_ima_xattr_data *xattr_value,
int xattr_len, const struct modsig *modsig, int pcr,
struct ima_template_desc *template_desc);
-void process_buffer_measurement(struct inode *inode, const void *buf, int size,
+void process_buffer_measurement(struct user_namespace *user_ns,
+ struct inode *inode, const void *buf, int size,
const char *eventname, enum ima_hooks func,
int pcr, const char *keyring);
void ima_audit_measurement(struct integrity_iint_cache *iint,
@@ -280,8 +282,9 @@ void ima_free_template_entry(struct ima_template_entry *entry);
const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
/* IMA policy related functions */
-int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
- enum ima_hooks func, int mask, int flags, int *pcr,
+int ima_match_policy(struct user_namespace *user_ns, struct inode *inode,
+ const struct cred *cred, u32 secid, enum ima_hooks func,
+ int mask, int flags, int *pcr,
struct ima_template_desc **template_desc,
const char *keyring);
void ima_init_policy(void);
@@ -312,7 +315,8 @@ int ima_appraise_measurement(enum ima_hooks func,
struct file *file, const unsigned char *filename,
struct evm_ima_xattr_data *xattr_value,
int xattr_len, const struct modsig *modsig);
-int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func);
+int ima_must_appraise(struct user_namespace *user_ns, struct inode *inode,
+ int mask, enum ima_hooks func);
void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file);
enum integrity_status ima_get_cache_status(struct integrity_iint_cache *iint,
enum ima_hooks func);
@@ -339,7 +343,8 @@ static inline int ima_appraise_measurement(enum ima_hooks func,
return INTEGRITY_UNKNOWN;
}
-static inline int ima_must_appraise(struct inode *inode, int mask,
+static inline int ima_must_appraise(struct user_namespace *user_ns,
+ struct inode *inode, int mask,
enum ima_hooks func)
{
return 0;
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 4f39fb93f278..ec51ada849a5 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -162,6 +162,7 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
/**
* ima_get_action - appraise & measure decision based on policy.
+ * @user_ns: userns of the mount through which the inode is accessed
* @inode: pointer to the inode associated with the object being validated
* @cred: pointer to credentials structure to validate
* @secid: secid of the task being validated
@@ -183,8 +184,9 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
* Returns IMA_MEASURE, IMA_APPRAISE mask.
*
*/
-int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
- int mask, enum ima_hooks func, int *pcr,
+int ima_get_action(struct user_namespace *user_ns, struct inode *inode,
+ const struct cred *cred, u32 secid, int mask,
+ enum ima_hooks func, int *pcr,
struct ima_template_desc **template_desc,
const char *keyring)
{
@@ -192,8 +194,8 @@ int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
flags &= ima_policy_flag;
- return ima_match_policy(inode, cred, secid, func, mask, flags, pcr,
- template_desc, keyring);
+ return ima_match_policy(user_ns, inode, cred, secid, func, mask, flags,
+ pcr, template_desc, keyring);
}
/*
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 3492f0b2da1c..162f00660a4a 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -63,7 +63,8 @@ bool is_ima_appraise_enabled(void)
*
* Return 1 to appraise or hash
*/
-int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func)
+int ima_must_appraise(struct user_namespace *user_ns, struct inode *inode,
+ int mask, enum ima_hooks func)
{
u32 secid;
@@ -71,8 +72,8 @@ int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func)
return 0;
security_task_getsecid(current, &secid);
- return ima_match_policy(inode, current_cred(), secid, func, mask,
- IMA_APPRAISE | IMA_HASH, NULL, NULL, NULL);
+ return ima_match_policy(user_ns, inode, current_cred(), secid, func,
+ mask, IMA_APPRAISE | IMA_HASH, NULL, NULL, NULL);
}
static int ima_fix_xattr(struct dentry *dentry,
@@ -345,7 +346,7 @@ int ima_check_blacklist(struct integrity_iint_cache *iint,
rc = is_binary_blacklisted(digest, digestsize);
if ((rc == -EPERM) && (iint->flags & IMA_MEASURE))
- process_buffer_measurement(NULL, digest, digestsize,
+ process_buffer_measurement(NULL, NULL, digest, digestsize,
"blacklisted-hash", NONE,
pcr, NULL);
}
@@ -496,6 +497,7 @@ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
/**
* ima_inode_post_setattr - reflect file metadata changes
+ * @user_ns: user namespace of the mount
* @dentry: pointer to the affected dentry
*
* Changes to a dentry's metadata might result in needing to appraise.
@@ -503,7 +505,7 @@ void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
* This function is called from notify_change(), which expects the caller
* to lock the inode's i_mutex.
*/
-void ima_inode_post_setattr(struct dentry *dentry)
+void ima_inode_post_setattr(struct user_namespace *user_ns, struct dentry *dentry)
{
struct inode *inode = d_backing_inode(dentry);
struct integrity_iint_cache *iint;
@@ -513,7 +515,7 @@ void ima_inode_post_setattr(struct dentry *dentry)
|| !(inode->i_opflags & IOP_XATTR))
return;
- action = ima_must_appraise(inode, MAY_ACCESS, POST_SETATTR);
+ action = ima_must_appraise(user_ns, inode, MAY_ACCESS, POST_SETATTR);
if (!action)
__vfs_removexattr(&init_user_ns, dentry, XATTR_NAME_IMA);
iint = integrity_iint_find(inode);
diff --git a/security/integrity/ima/ima_asymmetric_keys.c b/security/integrity/ima/ima_asymmetric_keys.c
index 1c68c500c26f..9810f3bfa57f 100644
--- a/security/integrity/ima/ima_asymmetric_keys.c
+++ b/security/integrity/ima/ima_asymmetric_keys.c
@@ -58,7 +58,7 @@ void ima_post_key_create_or_update(struct key *keyring, struct key *key,
* if the IMA policy is configured to measure a key linked
* to the given keyring.
*/
- process_buffer_measurement(NULL, payload, payload_len,
+ process_buffer_measurement(NULL, NULL, payload, payload_len,
keyring->description, KEY_CHECK, 0,
keyring->description);
}
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 2d1af8899cab..562003bab943 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -218,8 +218,8 @@ static int process_measurement(struct file *file, const struct cred *cred,
* bitmask based on the appraise/audit/measurement policy.
* Included is the appraise submask.
*/
- action = ima_get_action(inode, cred, secid, mask, func, &pcr,
- &template_desc, NULL);
+ action = ima_get_action(mnt_user_ns(file->f_path.mnt), inode, cred,
+ secid, mask, func, &pcr, &template_desc, NULL);
violation_check = ((func == FILE_CHECK || func == MMAP_CHECK) &&
(ima_policy_flag & IMA_MEASURE));
if (!action && !violation_check)
@@ -431,8 +431,9 @@ int ima_file_mprotect(struct vm_area_struct *vma, unsigned long prot)
security_task_getsecid(current, &secid);
inode = file_inode(vma->vm_file);
- action = ima_get_action(inode, current_cred(), secid, MAY_EXEC,
- MMAP_CHECK, &pcr, &template, 0);
+ action = ima_get_action(mnt_user_ns(vma->vm_file->f_path.mnt), inode,
+ current_cred(), secid, MAY_EXEC, MMAP_CHECK,
+ &pcr, &template, 0);
/* Is the mmap'ed file in policy? */
if (!(action & (IMA_MEASURE | IMA_APPRAISE_SUBMASK)))
@@ -568,12 +569,13 @@ EXPORT_SYMBOL_GPL(ima_file_hash);
* Skip calling process_measurement(), but indicate which newly, created
* tmpfiles are in policy.
*/
-void ima_post_create_tmpfile(struct inode *inode)
+void ima_post_create_tmpfile(struct user_namespace *user_ns,
+ struct inode *inode)
{
struct integrity_iint_cache *iint;
int must_appraise;
- must_appraise = ima_must_appraise(inode, MAY_ACCESS, FILE_CHECK);
+ must_appraise = ima_must_appraise(user_ns, inode, MAY_ACCESS, FILE_CHECK);
if (!must_appraise)
return;
@@ -589,18 +591,19 @@ void ima_post_create_tmpfile(struct inode *inode)
/**
* ima_post_path_mknod - mark as a new inode
+ * @user_ns: user namespace of the mount
* @dentry: newly created dentry
*
* Mark files created via the mknodat syscall as new, so that the
* file data can be written later.
*/
-void ima_post_path_mknod(struct dentry *dentry)
+void ima_post_path_mknod(struct user_namespace *user_ns, struct dentry *dentry)
{
struct integrity_iint_cache *iint;
struct inode *inode = dentry->d_inode;
int must_appraise;
- must_appraise = ima_must_appraise(inode, MAY_ACCESS, FILE_CHECK);
+ must_appraise = ima_must_appraise(user_ns, inode, MAY_ACCESS, FILE_CHECK);
if (!must_appraise)
return;
@@ -780,6 +783,7 @@ int ima_post_load_data(char *buf, loff_t size,
/*
* process_buffer_measurement - Measure the buffer to ima log.
+ * @userns: user namespace of the mount through which the inode is accessed
* @inode: inode associated with the object being measured (NULL for KEY_CHECK)
* @buf: pointer to the buffer that needs to be added to the log.
* @size: size of buffer(in bytes).
@@ -790,7 +794,8 @@ int ima_post_load_data(char *buf, loff_t size,
*
* Based on policy, the buffer is measured into the ima log.
*/
-void process_buffer_measurement(struct inode *inode, const void *buf, int size,
+void process_buffer_measurement(struct user_namespace *user_ns,
+ struct inode *inode, const void *buf, int size,
const char *eventname, enum ima_hooks func,
int pcr, const char *keyring)
{
@@ -823,7 +828,7 @@ void process_buffer_measurement(struct inode *inode, const void *buf, int size,
*/
if (func) {
security_task_getsecid(current, &secid);
- action = ima_get_action(inode, current_cred(), secid, 0, func,
+ action = ima_get_action(user_ns, inode, current_cred(), secid, 0, func,
&pcr, &template, keyring);
if (!(action & IMA_MEASURE))
return;
@@ -895,7 +900,8 @@ void ima_kexec_cmdline(int kernel_fd, const void *buf, int size)
if (!f.file)
return;
- process_buffer_measurement(file_inode(f.file), buf, size,
+ process_buffer_measurement(mnt_user_ns(f.file->f_path.mnt),
+ file_inode(f.file), buf, size,
"kexec-cmdline", KEXEC_CMDLINE, 0, NULL);
fdput(f);
}
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 9b5adeaa47fc..003d974ce2f3 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -497,10 +497,10 @@ static bool ima_match_keyring(struct ima_rule_entry *rule,
*
* Returns true on rule match, false on failure.
*/
-static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
+static bool ima_match_rules(struct ima_rule_entry *rule,
+ struct user_namespace *user_ns, struct inode *inode,
const struct cred *cred, u32 secid,
- enum ima_hooks func, int mask,
- const char *keyring)
+ enum ima_hooks func, int mask, const char *keyring)
{
int i;
@@ -539,7 +539,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
}
if ((rule->flags & IMA_FOWNER) &&
- !rule->fowner_op(inode->i_uid, rule->fowner))
+ !rule->fowner_op(i_uid_into_mnt(user_ns, inode), rule->fowner))
return false;
for (i = 0; i < MAX_LSM_RULES; i++) {
int rc = 0;
@@ -620,8 +620,9 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
* list when walking it. Reads are many orders of magnitude more numerous
* than writes so ima_match_policy() is classical RCU candidate.
*/
-int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
- enum ima_hooks func, int mask, int flags, int *pcr,
+int ima_match_policy(struct user_namespace *user_ns, struct inode *inode,
+ const struct cred *cred, u32 secid, enum ima_hooks func,
+ int mask, int flags, int *pcr,
struct ima_template_desc **template_desc,
const char *keyring)
{
@@ -637,8 +638,8 @@ int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
if (!(entry->action & actmask))
continue;
- if (!ima_match_rules(entry, inode, cred, secid, func, mask,
- keyring))
+ if (!ima_match_rules(entry, user_ns, inode, cred, secid, func,
+ mask, keyring))
continue;
action |= entry->flags & IMA_ACTION_FLAGS;
diff --git a/security/integrity/ima/ima_queue_keys.c b/security/integrity/ima/ima_queue_keys.c
index 69a8626a35c0..2bacc4f3e6ba 100644
--- a/security/integrity/ima/ima_queue_keys.c
+++ b/security/integrity/ima/ima_queue_keys.c
@@ -158,7 +158,7 @@ void ima_process_queued_keys(void)
list_for_each_entry_safe(entry, tmp, &ima_keys, list) {
if (!timer_expired)
- process_buffer_measurement(NULL, entry->payload,
+ process_buffer_measurement(NULL, NULL, entry->payload,
entry->payload_len,
entry->keyring_name,
KEY_CHECK, 0,
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 32/38] fat: handle idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (29 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 31/38] ima: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-30 22:50 ` Mauricio Vásquez Bernal
2020-11-28 21:35 ` [PATCH v3 33/38] ext4: support " Christian Brauner
` (5 subsequent siblings)
36 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
Let fat handle idmapped mounts. This allows to have the same fat mount appear
in multiple locations with different id mappings. This allows to expose a vfat
formatted USB stick to multiple user with different ids on the host or in user
namespaces allowing for dac permissions:
mount -o uid=1000,gid=1000 /dev/sdb /mnt
u1001@f2-vm:/lower1$ ls -ln /mnt/
total 4
-rwxr-xr-x 1 1000 1000 4 Oct 28 03:44 aaa
-rwxr-xr-x 1 1000 1000 0 Oct 28 01:09 bbb
-rwxr-xr-x 1 1000 1000 0 Oct 28 01:10 ccc
-rwxr-xr-x 1 1000 1000 0 Oct 28 03:46 ddd
-rwxr-xr-x 1 1000 1000 0 Oct 28 04:01 eee
mount2 --idmap both:1000:1001:1
u1001@f2-vm:/lower1$ ls -ln /lower1/
total 4
-rwxr-xr-x 1 1001 1001 4 Oct 28 03:44 aaa
-rwxr-xr-x 1 1001 1001 0 Oct 28 01:09 bbb
-rwxr-xr-x 1 1001 1001 0 Oct 28 01:10 ccc
-rwxr-xr-x 1 1001 1001 0 Oct 28 03:46 ddd
-rwxr-xr-x 1 1001 1001 0 Oct 28 04:01 eee
u1001@f2-vm:/lower1$ touch /lower1/fff
u1001@f2-vm:/lower1$ ls -ln /lower1/fff
-rwxr-xr-x 1 1001 1001 0 Oct 28 04:03 /lower1/fff
u1001@f2-vm:/lower1$ ls -ln /mnt/fff
-rwxr-xr-x 1 1000 1000 0 Oct 28 04:03 /mnt/fff
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
fs/fat/file.c | 15 ++++++++-------
fs/fat/namei_msdos.c | 2 +-
fs/fat/namei_vfat.c | 2 +-
3 files changed, 10 insertions(+), 9 deletions(-)
diff --git a/fs/fat/file.c b/fs/fat/file.c
index 5b12cf209801..15dc8d27aa72 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -398,7 +398,7 @@ int fat_getattr(const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int flags)
{
struct inode *inode = d_inode(path->dentry);
- generic_fillattr(&init_user_ns, inode, stat);
+ generic_fillattr(mnt_user_ns(path->mnt), inode, stat);
stat->blksize = MSDOS_SB(inode->i_sb)->cluster_size;
if (MSDOS_SB(inode->i_sb)->options.nfs == FAT_NFS_NOSTALE_RO) {
@@ -447,12 +447,13 @@ static int fat_sanitize_mode(const struct msdos_sb_info *sbi,
return 0;
}
-static int fat_allow_set_time(struct msdos_sb_info *sbi, struct inode *inode)
+static int fat_allow_set_time(struct user_namespace *user_ns,
+ struct msdos_sb_info *sbi, struct inode *inode)
{
umode_t allow_utime = sbi->options.allow_utime;
- if (!uid_eq(current_fsuid(), inode->i_uid)) {
- if (in_group_p(inode->i_gid))
+ if (!uid_eq(current_fsuid(), i_uid_into_mnt(user_ns, inode))) {
+ if (in_group_p(i_gid_into_mnt(user_ns, inode)))
allow_utime >>= 3;
if (allow_utime & MAY_WRITE)
return 1;
@@ -477,11 +478,11 @@ int fat_setattr(struct user_namespace *user_ns, struct dentry *dentry,
/* Check for setting the inode time. */
ia_valid = attr->ia_valid;
if (ia_valid & TIMES_SET_FLAGS) {
- if (fat_allow_set_time(sbi, inode))
+ if (fat_allow_set_time(user_ns, sbi, inode))
attr->ia_valid &= ~TIMES_SET_FLAGS;
}
- error = setattr_prepare(&init_user_ns, dentry, attr);
+ error = setattr_prepare(user_ns, dentry, attr);
attr->ia_valid = ia_valid;
if (error) {
if (sbi->options.quiet)
@@ -551,7 +552,7 @@ int fat_setattr(struct user_namespace *user_ns, struct dentry *dentry,
fat_truncate_time(inode, &attr->ia_mtime, S_MTIME);
attr->ia_valid &= ~(ATTR_ATIME|ATTR_CTIME|ATTR_MTIME);
- setattr_copy(&init_user_ns, inode, attr);
+ setattr_copy(user_ns, inode, attr);
mark_inode_dirty(inode);
out:
return error;
diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
index 608b0606f3ca..0f871a1b6620 100644
--- a/fs/fat/namei_msdos.c
+++ b/fs/fat/namei_msdos.c
@@ -666,7 +666,7 @@ static struct file_system_type msdos_fs_type = {
.name = "msdos",
.mount = msdos_mount,
.kill_sb = kill_block_super,
- .fs_flags = FS_REQUIRES_DEV,
+ .fs_flags = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
};
MODULE_ALIAS_FS("msdos");
diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index 34903d14d6a6..177d939b95da 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -1063,7 +1063,7 @@ static struct file_system_type vfat_fs_type = {
.name = "vfat",
.mount = vfat_mount,
.kill_sb = kill_block_super,
- .fs_flags = FS_REQUIRES_DEV,
+ .fs_flags = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
};
MODULE_ALIAS_FS("vfat");
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 33/38] ext4: support idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (30 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 32/38] fat: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-30 22:52 ` Mauricio Vásquez Bernal
2020-12-01 10:54 ` Christoph Hellwig
2020-11-28 21:35 ` [PATCH v3 34/38] ecryptfs: do not mount on top of " Christian Brauner
` (4 subsequent siblings)
36 siblings, 2 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
This enables ext4 to support idmapped mounts. All dedicated helpers we need for
this exist. The vfs will have already made sure that the fsids can be translated
after having been shifted if they are on an idmapped mount.
This implements helpers for the new inode operations that we've added. The core
change is the allocation of a new inode based on the mount's user namespace.
Code duplication is virtually non-existent because we can implement the
non-idmapped mount aware inode methods on top of the idmapped mount aware inode
methods. If the initial user namespace is passed nothing changes so non-idmapped
mounts will see identical behavior as before.
It is also noteworthy that the idmapped mount implementation allows us to
cleanly handle ioctls() too. I've kept this as a single patch for now since the
change is overall fairly mechanical but I'm happy to split this.
Let's create simple example where we idmap an ext4 filesystem:
root@f2-vm:~# truncate -s 5G ext4.img
root@f2-vm:~# mkfs.ext4 ./ext4.img
mke2fs 1.45.5 (07-Jan-2020)
Discarding device blocks: done
Creating filesystem with 1310720 4k blocks and 327680 inodes
Filesystem UUID: 3fd91794-c6ca-4b0f-9964-289a000919cf
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736
Allocating group tables: done
Writing inode tables: done
Creating journal (16384 blocks): done
Writing superblocks and filesystem accounting information: done
root@f2-vm:~# losetup -f --show ./ext4.img
/dev/loop0
root@f2-vm:~# mount /dev/loop0 /mnt
root@f2-vm:~# ls -al /mnt/
total 24
drwxr-xr-x 3 root root 4096 Oct 28 13:34 .
drwxr-xr-x 30 root root 4096 Oct 28 13:22 ..
drwx------ 2 root root 16384 Oct 28 13:34 lost+found
# Let's create an idmapped mount at /idmapped1 where we map uid and gid 0 to
# uid and gid 1000
root@f2-vm:/# ./mount2 -mb:0:1000:1 /mnt/ /idmapped1/
root@f2-vm:/# ls -al /idmapped1/
total 24
drwxr-xr-x 3 ubuntu ubuntu 4096 Oct 28 13:34 .
drwxr-xr-x 30 root root 4096 Oct 28 13:22 ..
drwx------ 2 ubuntu ubuntu 16384 Oct 28 13:34 lost+found
# Let's create an idmapped mount at /idmapped2 where we map uid and gid 0 to
# uid and gid 2000
root@f2-vm:/# ./mount2 -mb:0:2000:1 /mnt/ /idmapped2/
root@f2-vm:/# ls -al /idmapped2/
total 24
drwxr-xr-x 3 2000 2000 4096 Oct 28 13:34 .
drwxr-xr-x 31 root root 4096 Oct 28 13:39 ..
drwx------ 2 2000 2000 16384 Oct 28 13:34 lost+found
Let's create another example where we idmap the rootfs filesystem without a
mapping for uid 0 and gid 0:
# Create an idmapped mount of for a full POSIX range of rootfs under /mnt
# but without a mapping for uid 0 to reduce attack surface
root@f2-vm:/# ./mount2 -mb:1:1:65536 / /mnt/
# Since we don't have a mapping for uid and gid 0 all files owned by uid and
# gid 0 should show up as uid and gid 65534:
root@f2-vm:/# ls -al /mnt/
total 664
drwxr-xr-x 31 nobody nogroup 4096 Oct 28 13:39 .
drwxr-xr-x 31 root root 4096 Oct 28 13:39 ..
lrwxrwxrwx 1 nobody nogroup 7 Aug 25 07:44 bin -> usr/bin
drwxr-xr-x 4 nobody nogroup 4096 Oct 28 13:17 boot
drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:48 dev
drwxr-xr-x 81 nobody nogroup 4096 Oct 28 04:00 etc
drwxr-xr-x 4 nobody nogroup 4096 Oct 28 04:00 home
lrwxrwxrwx 1 nobody nogroup 7 Aug 25 07:44 lib -> usr/lib
lrwxrwxrwx 1 nobody nogroup 9 Aug 25 07:44 lib32 -> usr/lib32
lrwxrwxrwx 1 nobody nogroup 9 Aug 25 07:44 lib64 -> usr/lib64
lrwxrwxrwx 1 nobody nogroup 10 Aug 25 07:44 libx32 -> usr/libx32
drwx------ 2 nobody nogroup 16384 Aug 25 07:47 lost+found
drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:44 media
drwxr-xr-x 31 nobody nogroup 4096 Oct 28 13:39 mnt
drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:44 opt
drwxr-xr-x 2 nobody nogroup 4096 Apr 15 2020 proc
drwx--x--x 6 nobody nogroup 4096 Oct 28 13:34 root
drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:46 run
lrwxrwxrwx 1 nobody nogroup 8 Aug 25 07:44 sbin -> usr/sbin
drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:44 srv
drwxr-xr-x 2 nobody nogroup 4096 Apr 15 2020 sys
drwxrwxrwt 10 nobody nogroup 4096 Oct 28 13:19 tmp
drwxr-xr-x 14 nobody nogroup 4096 Oct 20 13:00 usr
drwxr-xr-x 12 nobody nogroup 4096 Aug 25 07:45 var
# Since we do have a mapping for uid and gid 1000 all files owned by uid and
# gid 1000 should simply show up as uid and gid 1000:
root@f2-vm:/# ls -al /mnt/home/ubuntu/
total 40
drwxr-xr-x 3 ubuntu ubuntu 4096 Oct 28 00:43 .
drwxr-xr-x 4 nobody nogroup 4096 Oct 28 04:00 ..
-rw------- 1 ubuntu ubuntu 2936 Oct 28 12:26 .bash_history
-rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile
-rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
unchanged
/* v3 */
unchanged
---
fs/ext4/Kconfig | 9 +++++++++
fs/ext4/acl.c | 2 +-
fs/ext4/ext4.h | 13 +++++++------
fs/ext4/ialloc.c | 7 ++++---
fs/ext4/inode.c | 11 +++++++----
fs/ext4/ioctl.c | 18 ++++++++++--------
fs/ext4/namei.c | 30 ++++++++++++++++--------------
fs/ext4/super.c | 6 +++++-
8 files changed, 59 insertions(+), 37 deletions(-)
diff --git a/fs/ext4/Kconfig b/fs/ext4/Kconfig
index 619dd35ddd48..5918c05cfe5b 100644
--- a/fs/ext4/Kconfig
+++ b/fs/ext4/Kconfig
@@ -118,3 +118,12 @@ config EXT4_KUNIT_TESTS
to the KUnit documentation in Documentation/dev-tools/kunit/.
If unsure, say N.
+
+config EXT4_IDMAP_MOUNTS
+ bool "Support vfs idmapped mounts in ext4"
+ depends on EXT4_FS
+ default n
+ help
+ The vfs allows to expose a filesystem at different mountpoints with
+ differnet idmappings. Allow ext4 to be exposed through idmapped
+ mounts.
diff --git a/fs/ext4/acl.c b/fs/ext4/acl.c
index 3ab0a69b974b..7c413bd4d2f2 100644
--- a/fs/ext4/acl.c
+++ b/fs/ext4/acl.c
@@ -246,7 +246,7 @@ ext4_set_acl(struct user_namespace *user_ns, struct inode *inode,
ext4_fc_start_update(inode);
if ((type == ACL_TYPE_ACCESS) && acl) {
- error = posix_acl_update_mode(&init_user_ns, inode, &mode, &acl);
+ error = posix_acl_update_mode(user_ns, inode, &mode, &acl);
if (error)
goto out_stop;
if (mode != inode->i_mode)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index b89efd36ea7e..bf6c92794480 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2724,18 +2724,19 @@ extern int ext4fs_dirhash(const struct inode *dir, const char *name, int len,
/* ialloc.c */
extern int ext4_mark_inode_used(struct super_block *sb, int ino);
-extern struct inode *__ext4_new_inode(handle_t *, struct inode *, umode_t,
+extern struct inode *__ext4_new_inode(struct user_namespace *, handle_t *,
+ struct inode *, umode_t,
const struct qstr *qstr, __u32 goal,
uid_t *owner, __u32 i_flags,
int handle_type, unsigned int line_no,
int nblocks);
-#define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
- __ext4_new_inode((handle), (dir), (mode), (qstr), (goal), (owner), \
- i_flags, 0, 0, 0)
-#define ext4_new_inode_start_handle(dir, mode, qstr, goal, owner, \
+#define ext4_new_inode(handle, dir, mode, qstr, goal, owner, i_flags) \
+ __ext4_new_inode(&init_user_ns, (handle), (dir), (mode), (qstr), \
+ (goal), (owner), i_flags, 0, 0, 0)
+#define ext4_new_inode_start_handle(user_ns, dir, mode, qstr, goal, owner, \
type, nblocks) \
- __ext4_new_inode(NULL, (dir), (mode), (qstr), (goal), (owner), \
+ __ext4_new_inode((user_ns), NULL, (dir), (mode), (qstr), (goal), (owner), \
0, (type), __LINE__, (nblocks))
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index d91f69282311..93251687c6a2 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -919,7 +919,8 @@ static int ext4_xattr_credits_for_new_inode(struct inode *dir, mode_t mode,
* For other inodes, search forward from the parent directory's block
* group to find a free inode.
*/
-struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir,
+struct inode *__ext4_new_inode(struct user_namespace *user_ns,
+ handle_t *handle, struct inode *dir,
umode_t mode, const struct qstr *qstr,
__u32 goal, uid_t *owner, __u32 i_flags,
int handle_type, unsigned int line_no,
@@ -969,10 +970,10 @@ struct inode *__ext4_new_inode(handle_t *handle, struct inode *dir,
i_gid_write(inode, owner[1]);
} else if (test_opt(sb, GRPID)) {
inode->i_mode = mode;
- inode->i_uid = current_fsuid();
+ inode->i_uid = fsuid_into_mnt(user_ns);
inode->i_gid = dir->i_gid;
} else
- inode_init_owner(inode, &init_user_ns, dir, mode);
+ inode_init_owner(inode, user_ns, dir, mode);
if (ext4_has_feature_project(sb) &&
ext4_test_inode_flag(dir, EXT4_INODE_PROJINHERIT))
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index a1a4a00ecfa0..0bbedb8070d9 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -20,6 +20,7 @@
*/
#include <linux/fs.h>
+#include <linux/mount.h>
#include <linux/time.h>
#include <linux/highuid.h>
#include <linux/pagemap.h>
@@ -5325,7 +5326,7 @@ int ext4_setattr(struct user_namespace *user_ns, struct dentry *dentry,
ATTR_GID | ATTR_TIMES_SET))))
return -EPERM;
- error = setattr_prepare(&init_user_ns, dentry, attr);
+ error = setattr_prepare(user_ns, dentry, attr);
if (error)
return error;
@@ -5500,7 +5501,7 @@ int ext4_setattr(struct user_namespace *user_ns, struct dentry *dentry,
}
if (!error) {
- setattr_copy(&init_user_ns, inode, attr);
+ setattr_copy(user_ns, inode, attr);
mark_inode_dirty(inode);
}
@@ -5512,7 +5513,7 @@ int ext4_setattr(struct user_namespace *user_ns, struct dentry *dentry,
ext4_orphan_del(NULL, inode);
if (!error && (ia_valid & ATTR_MODE))
- rc = posix_acl_chmod(&init_user_ns, inode, inode->i_mode);
+ rc = posix_acl_chmod(user_ns, inode, inode->i_mode);
err_out:
if (error)
@@ -5526,6 +5527,7 @@ int ext4_setattr(struct user_namespace *user_ns, struct dentry *dentry,
int ext4_getattr(const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int query_flags)
{
+ struct user_namespace *user_ns;
struct inode *inode = d_inode(path->dentry);
struct ext4_inode *raw_inode;
struct ext4_inode_info *ei = EXT4_I(inode);
@@ -5559,7 +5561,8 @@ int ext4_getattr(const struct path *path, struct kstat *stat,
STATX_ATTR_NODUMP |
STATX_ATTR_VERITY);
- generic_fillattr(&init_user_ns, inode, stat);
+ user_ns = mnt_user_ns(path->mnt);
+ generic_fillattr(user_ns, inode, stat);
return 0;
}
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index e35aba820254..6fff34587f0b 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -111,6 +111,7 @@ void ext4_reset_inode_seed(struct inode *inode)
*
*/
static long swap_inode_boot_loader(struct super_block *sb,
+ struct user_namespace *user_ns,
struct inode *inode)
{
handle_t *handle;
@@ -139,7 +140,7 @@ static long swap_inode_boot_loader(struct super_block *sb,
}
if (IS_RDONLY(inode) || IS_APPEND(inode) || IS_IMMUTABLE(inode) ||
- !inode_owner_or_capable(&init_user_ns, inode) || !capable(CAP_SYS_ADMIN)) {
+ !inode_owner_or_capable(user_ns, inode) || !capable(CAP_SYS_ADMIN)) {
err = -EPERM;
goto journal_err_out;
}
@@ -814,6 +815,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
struct inode *inode = file_inode(filp);
struct super_block *sb = inode->i_sb;
struct ext4_inode_info *ei = EXT4_I(inode);
+ struct user_namespace *user_ns = mnt_user_ns(filp->f_path.mnt);
unsigned int flags;
ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
@@ -829,7 +831,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
case FS_IOC_SETFLAGS: {
int err;
- if (!inode_owner_or_capable(&init_user_ns, inode))
+ if (!inode_owner_or_capable(user_ns, inode))
return -EACCES;
if (get_user(flags, (int __user *) arg))
@@ -871,7 +873,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
__u32 generation;
int err;
- if (!inode_owner_or_capable(&init_user_ns, inode))
+ if (!inode_owner_or_capable(user_ns, inode))
return -EPERM;
if (ext4_has_metadata_csum(inode->i_sb)) {
@@ -1010,7 +1012,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
case EXT4_IOC_MIGRATE:
{
int err;
- if (!inode_owner_or_capable(&init_user_ns, inode))
+ if (!inode_owner_or_capable(user_ns, inode))
return -EACCES;
err = mnt_want_write_file(filp);
@@ -1032,7 +1034,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
case EXT4_IOC_ALLOC_DA_BLKS:
{
int err;
- if (!inode_owner_or_capable(&init_user_ns, inode))
+ if (!inode_owner_or_capable(user_ns, inode))
return -EACCES;
err = mnt_want_write_file(filp);
@@ -1051,7 +1053,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
err = mnt_want_write_file(filp);
if (err)
return err;
- err = swap_inode_boot_loader(sb, inode);
+ err = swap_inode_boot_loader(sb, user_ns, inode);
mnt_drop_write_file(filp);
return err;
}
@@ -1214,7 +1216,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
case EXT4_IOC_CLEAR_ES_CACHE:
{
- if (!inode_owner_or_capable(&init_user_ns, inode))
+ if (!inode_owner_or_capable(user_ns, inode))
return -EACCES;
ext4_clear_inode_es(inode);
return 0;
@@ -1260,7 +1262,7 @@ static long __ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return -EFAULT;
/* Make sure caller has proper permission */
- if (!inode_owner_or_capable(&init_user_ns, inode))
+ if (!inode_owner_or_capable(user_ns, inode))
return -EACCES;
if (fa.fsx_xflags & ~EXT4_SUPPORTED_FS_XFLAGS)
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 194bc37fba55..f76d2f730366 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -2616,8 +2616,8 @@ static int ext4_create(struct user_namespace *user_ns, struct inode *dir,
credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
retry:
- inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
- NULL, EXT4_HT_DIR, credits);
+ inode = ext4_new_inode_start_handle(user_ns, dir, mode, &dentry->d_name,
+ 0, NULL, EXT4_HT_DIR, credits);
handle = ext4_journal_current_handle();
err = PTR_ERR(inode);
if (!IS_ERR(inode)) {
@@ -2651,8 +2651,8 @@ static int ext4_mknod(struct user_namespace *user_ns, struct inode *dir,
credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
retry:
- inode = ext4_new_inode_start_handle(dir, mode, &dentry->d_name, 0,
- NULL, EXT4_HT_DIR, credits);
+ inode = ext4_new_inode_start_handle(user_ns, dir, mode, &dentry->d_name,
+ 0, NULL, EXT4_HT_DIR, credits);
handle = ext4_journal_current_handle();
err = PTR_ERR(inode);
if (!IS_ERR(inode)) {
@@ -2683,7 +2683,7 @@ static int ext4_tmpfile(struct user_namespace *user_ns, struct inode *dir,
return err;
retry:
- inode = ext4_new_inode_start_handle(dir, mode,
+ inode = ext4_new_inode_start_handle(user_ns, dir, mode,
NULL, 0, NULL,
EXT4_HT_DIR,
EXT4_MAXQUOTAS_INIT_BLOCKS(dir->i_sb) +
@@ -2798,7 +2798,7 @@ static int ext4_mkdir(struct user_namespace *user_ns, struct inode *dir,
credits = (EXT4_DATA_TRANS_BLOCKS(dir->i_sb) +
EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3);
retry:
- inode = ext4_new_inode_start_handle(dir, S_IFDIR | mode,
+ inode = ext4_new_inode_start_handle(user_ns, dir, S_IFDIR | mode,
&dentry->d_name,
0, NULL, EXT4_HT_DIR, credits);
handle = ext4_journal_current_handle();
@@ -3335,7 +3335,7 @@ static int ext4_symlink(struct user_namespace *user_ns, struct inode *dir,
EXT4_INDEX_EXTRA_TRANS_BLOCKS + 3;
}
- inode = ext4_new_inode_start_handle(dir, S_IFLNK|S_IRWXUGO,
+ inode = ext4_new_inode_start_handle(user_ns, dir, S_IFLNK|S_IRWXUGO,
&dentry->d_name, 0, NULL,
EXT4_HT_DIR, credits);
handle = ext4_journal_current_handle();
@@ -3667,7 +3667,8 @@ static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)
}
}
-static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent,
+static struct inode *ext4_whiteout_for_rename(struct user_namespace *user_ns,
+ struct ext4_renament *ent,
int credits, handle_t **h)
{
struct inode *wh;
@@ -3681,7 +3682,8 @@ static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent,
credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) +
EXT4_XATTR_TRANS_BLOCKS + 4);
retry:
- wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE,
+ wh = ext4_new_inode_start_handle(user_ns, ent->dir,
+ S_IFCHR | WHITEOUT_MODE,
&ent->dentry->d_name, 0, NULL,
EXT4_HT_DIR, credits);
@@ -3708,9 +3710,9 @@ static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent,
* while new_{dentry,inode) refers to the destination dentry/inode
* This comes from rename(const char *oldpath, const char *newpath)
*/
-static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
- struct inode *new_dir, struct dentry *new_dentry,
- unsigned int flags)
+static int ext4_rename(struct user_namespace *user_ns, struct inode *old_dir,
+ struct dentry *old_dentry, struct inode *new_dir,
+ struct dentry *new_dentry, unsigned int flags)
{
handle_t *handle = NULL;
struct ext4_renament old = {
@@ -3794,7 +3796,7 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
goto end_rename;
}
} else {
- whiteout = ext4_whiteout_for_rename(&old, credits, &handle);
+ whiteout = ext4_whiteout_for_rename(user_ns, &old, credits, &handle);
if (IS_ERR(whiteout)) {
retval = PTR_ERR(whiteout);
whiteout = NULL;
@@ -4108,7 +4110,7 @@ static int ext4_rename2(struct user_namespace *user_ns, struct inode *old_dir,
new_dir, new_dentry);
}
- return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
+ return ext4_rename(user_ns, old_dir, old_dentry, new_dir, new_dentry, flags);
}
/*
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 6633b20224d5..6420bd1d569a 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -5008,7 +5008,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
}
block = ext4_count_free_clusters(sb);
- ext4_free_blocks_count_set(sbi->s_es,
+ ext4_free_blocks_count_set(sbi->s_es,
EXT4_C2B(sbi, block));
ext4_superblock_csum_set(sb);
err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
@@ -6631,7 +6631,11 @@ static struct file_system_type ext4_fs_type = {
.name = "ext4",
.mount = ext4_mount,
.kill_sb = kill_block_super,
+#ifdef CONFIG_EXT4_IDMAP_MOUNTS
+ .fs_flags = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
+#else
.fs_flags = FS_REQUIRES_DEV,
+#endif
};
MODULE_ALIAS_FS("ext4");
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 34/38] ecryptfs: do not mount on top of idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (31 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 33/38] ext4: support " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 35/38] overlayfs: " Christian Brauner
` (3 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
Prevent ecryptfs from being mounted on top of idmapped mounts until we have
ported it to handle this case and added proper testing for it.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
patch introduced
/* v3 */
- David Howells <dhowells@redhat.com>:
- Adapt check after removing mnt_idmapped() helper.
---
fs/ecryptfs/main.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/fs/ecryptfs/main.c b/fs/ecryptfs/main.c
index e63259fdef28..cdf40a54a35d 100644
--- a/fs/ecryptfs/main.c
+++ b/fs/ecryptfs/main.c
@@ -531,6 +531,12 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags
goto out_free;
}
+ if (mnt_user_ns(path.mnt) != &init_user_ns) {
+ rc = -EINVAL;
+ printk(KERN_ERR "Mounting on idmapped mounts currently disallowed\n");
+ goto out_free;
+ }
+
if (check_ruid && !uid_eq(d_inode(path.dentry)->i_uid, current_uid())) {
rc = -EPERM;
printk(KERN_ERR "Mount of device (uid: %d) not owned by "
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 35/38] overlayfs: do not mount on top of idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (32 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 34/38] ecryptfs: do not mount on top of " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 36/38] fs: introduce MOUNT_ATTR_IDMAP Christian Brauner
` (2 subsequent siblings)
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
Prevent overlayfs from being mounted on top of idmapped mounts until we
have ported it to handle this case and added proper testing for it.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
patch introduced
/* v3 */
- Amir Goldstein <amir73il@gmail.com>:
- Move check for idmapped lower layers into ovl_mount_dir_noesc().
- David Howells <dhowells@redhat.com>:
- Adapt check after removing mnt_idmapped() helper.
---
fs/overlayfs/super.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 0d4f2baf6836..5002f97b01e6 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -811,6 +811,10 @@ static int ovl_mount_dir_noesc(const char *name, struct path *path)
pr_err("filesystem on '%s' not supported\n", name);
goto out_put;
}
+ if (mnt_user_ns(path->mnt) != &init_user_ns) {
+ pr_err("idmapped layers are currently not supported\n");
+ goto out_put;
+ }
if (!d_is_dir(path->dentry)) {
pr_err("'%s' not a directory\n", name);
goto out_put;
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 36/38] fs: introduce MOUNT_ATTR_IDMAP
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (33 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 35/38] overlayfs: " Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 37/38] tests: extend mount_setattr tests Christian Brauner
2020-11-28 22:54 ` [PATCH v3 00/38] idmapped mounts Serge E. Hallyn
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig,
Mauricio Vásquez Bernal
Introduce a new mount bind mount property to allow idmapping mounts. The
MOUNT_ATTR_IDMAP flag can be set via the new mount_setattr() syscall
together with a file descriptor referring to a user namespace.
The user namespace referenced by the namespace file descriptor will be
attached to the bind mount. All interactions with the filesystem going
through that mount will be idmapped according to the mapping specified in
the user namespace attached to it.
Using user namespaces to mark mounts means we can reuse all the existing
infrastructure in the kernel that already exists to handle idmappings and can
also use this for permission checking to allow unprivileged user to create
idmapped mounts in the future.
Idmapping a mount is decoupled from the caller's user and mount namespace.
This means idmapped mounts can be created in the initial user namespace
which is an important use-case for systemd-homed, portable usb-sticks
between systems, sharing data between the initial user namespace and
unprivileged containers, and other use-cases that have been brought up. For
example, assume a home directory where all files are owned by uid and gid
1000 and the home directory is brought to a new laptop where the user has
id 12345. The system administrator can simply create a mount of this home
directory with a mapping of 1000:12345:1 and other mappings to indicate the ids
should be kept. (With this it is e.g. also possible to create idmapped mounts on
the host with an identity mapping 1:1:100000 where the root user is not mapped.
A user with root access that e.g. has been pivot rooted into such a mount on the
host will be not be able to execute, read, write, or create files as root.)
Given that idmapping a mount is decoupled from the caller's user namespace
a sufficiently privileged process such as a container manager can set up a
shifted mount for the container and the container can simply pivot root to
it. There's no need for the container to do anything. The mount will appear
correctly mapped independent of the user namespace the container uses. This
means we don't need to mark a mount as idmappable.
In order to create an idmapped mount the caller must currently be privileged in
the user namespace of the superblock the mount belongs to. Currently, once a
mount has been idmapped we don't allow it to change its mapping. This can be
changed in the future if the use-cases arise.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Mauricio Vásquez Bernal <mauricio@kinvolk.io>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
- Christoph Hellwig <hch@lst.de>:
- Drop kconfig option to make vfs idmappings unconditional.
- Move introduction of MOUNT_ATTR_IDMAP to the end of the series after all
internal changes have been done.
- Move MOUNT_ATTR_IDMAP handling from build_mount_kattr() to separate
build_mount_idmapped() helper.
- Move MNT_IDMAPPED handling from do_mount_setattr() into separate
do_mount_idmap() helper.
- Use more helpers instead of one big function for mount attribute changes.
- Mauricio Vásquez Bernal <mauricio@kinvolk.io>:
- Recalculate flags before checking can_change_locked_flags().
/* v3 */
- David Howells <dhowells@redhat.com>:
- Use smp_load_acquire() and smp_store_release() in mnt_user_ns() and do_idmap_mount().
- Remove all references to MNT_IDMAPPED now that the flag has been removed.
---
fs/internal.h | 1 +
fs/namespace.c | 126 +++++++++++++++++++++++++++++++++++--
fs/proc_namespace.c | 3 +
include/linux/fs.h | 2 +-
include/linux/mount.h | 3 +-
include/uapi/linux/mount.h | 5 +-
6 files changed, 133 insertions(+), 7 deletions(-)
diff --git a/fs/internal.h b/fs/internal.h
index a5a6c470dc07..b0978274155f 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -88,6 +88,7 @@ struct mount_kattr {
unsigned int propagation;
unsigned int lookup_flags;
bool recurse;
+ struct user_namespace *mnt_user_ns;
};
extern struct vfsmount *lookup_mnt(const struct path *);
diff --git a/fs/namespace.c b/fs/namespace.c
index a1fda548c3af..a74559c8093c 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -25,6 +25,7 @@
#include <linux/proc_ns.h>
#include <linux/magic.h>
#include <linux/memblock.h>
+#include <linux/proc_fs.h>
#include <linux/task_work.h>
#include <linux/sched/task.h>
#include <uapi/linux/mount.h>
@@ -3468,7 +3469,8 @@ static int build_attr_flags(unsigned int attr_flags, unsigned int *flags)
MOUNT_ATTR_NODEV |
MOUNT_ATTR_NOEXEC |
MOUNT_ATTR__ATIME |
- MOUNT_ATTR_NODIRATIME))
+ MOUNT_ATTR_NODIRATIME |
+ MOUNT_ATTR_IDMAP))
return -EINVAL;
if (attr_flags & MOUNT_ATTR_RDONLY)
@@ -3508,6 +3510,14 @@ SYSCALL_DEFINE3(fsmount, int, fs_fd, unsigned int, flags,
if ((flags & ~(FSMOUNT_CLOEXEC)) != 0)
return -EINVAL;
+ if (attr_flags & ~(MOUNT_ATTR_RDONLY |
+ MOUNT_ATTR_NOSUID |
+ MOUNT_ATTR_NODEV |
+ MOUNT_ATTR_NOEXEC |
+ MOUNT_ATTR__ATIME |
+ MOUNT_ATTR_NODIRATIME))
+ return -EINVAL;
+
ret = build_attr_flags(attr_flags, &mnt_flags);
if (ret)
return ret;
@@ -3830,6 +3840,32 @@ static unsigned int recalc_flags(struct mount_kattr *kattr, struct mount *mnt)
return flags;
}
+static int can_idmap_mount(const struct mount_kattr *kattr, struct mount *mnt)
+{
+ struct vfsmount *m = &mnt->mnt;
+
+ if (!kattr->mnt_user_ns)
+ return 0;
+
+ /*
+ * Once a mount has been idmapped we don't allow it to change its
+ * mapping. It makes things simpler and callers can just create
+ * another bind-mount they can idmap if they want to.
+ */
+ if (mnt_user_ns(m) != &init_user_ns)
+ return -EPERM;
+
+ /* The underlying filesystem doesn't support idmapped mounts yet. */
+ if (!(m->mnt_sb->s_type->fs_flags & FS_ALLOW_IDMAP))
+ return -EINVAL;
+
+ /* We're controlling the superblock. */
+ if (!ns_capable(m->mnt_sb->s_user_ns, CAP_SYS_ADMIN))
+ return -EPERM;
+
+ return 0;
+}
+
static struct mount *mount_setattr_prepare(struct mount_kattr *kattr,
struct mount *mnt, int *err)
{
@@ -3854,6 +3890,10 @@ static struct mount *mount_setattr_prepare(struct mount_kattr *kattr,
goto out;
}
+ *err = can_idmap_mount(kattr, m);
+ if (*err)
+ goto out;
+
last = m;
if ((kattr->attr_set & MNT_READONLY) &&
@@ -3868,6 +3908,18 @@ static struct mount *mount_setattr_prepare(struct mount_kattr *kattr,
return last;
}
+static void do_idmap_mount(const struct mount_kattr *kattr, struct mount *mnt)
+{
+ struct user_namespace *user_ns;
+
+ if (!kattr->mnt_user_ns)
+ return;
+
+ user_ns = get_user_ns(kattr->mnt_user_ns);
+ /* Pairs with smp_load_acquire() in mnt_user_ns(). */
+ smp_store_release(&mnt->mnt.mnt_user_ns, user_ns);
+}
+
static void mount_setattr_commit(struct mount_kattr *kattr, struct mount *mnt,
struct mount *last, int err)
{
@@ -3877,6 +3929,7 @@ static void mount_setattr_commit(struct mount_kattr *kattr, struct mount *mnt,
if (!err) {
unsigned int flags;
+ do_idmap_mount(kattr, m);
flags = recalc_flags(kattr, m);
WRITE_ONCE(m->mnt.mnt_flags, flags);
}
@@ -3949,7 +4002,65 @@ static int do_mount_setattr(struct path *path, struct mount_kattr *kattr)
return err;
}
-static int build_mount_kattr(const struct mount_attr *attr,
+static int build_mount_idmapped(const struct mount_attr *attr, size_t usize,
+ struct mount_kattr *kattr, unsigned int flags)
+{
+ int err = 0;
+ struct ns_common *ns;
+ struct user_namespace *user_ns;
+ struct file *file;
+
+ if (!((attr->attr_set | attr->attr_clr) & MOUNT_ATTR_IDMAP))
+ return 0;
+
+ /*
+ * We currently do not support clearing an idmapped mount. If this ever
+ * is a use-case we can revisit this but for now let's keep it simple
+ * and not allow it.
+ */
+ if (attr->attr_clr & MOUNT_ATTR_IDMAP)
+ return -EINVAL;
+
+ if (usize < MOUNT_ATTR_SIZE_VER1)
+ return -EINVAL;
+
+ if (attr->userns_fd > INT_MAX)
+ return -EINVAL;
+
+ file = fget(attr->userns_fd);
+ if (!file)
+ return -EBADF;
+
+ if (!proc_ns_file(file)) {
+ err = -EINVAL;
+ goto out_fput;
+ }
+
+ ns = get_proc_ns(file_inode(file));
+ if (ns->ops->type != CLONE_NEWUSER) {
+ err = -EINVAL;
+ goto out_fput;
+ }
+
+ /*
+ * The init_user_ns is used to indicate that a vfsmount is not idmapped.
+ * This is simpler than just having to treat NULL as unmapped. Users
+ * wanting to idmap a mount to init_user_ns can just use a namespace
+ * with an identity mapping.
+ */
+ user_ns = container_of(ns, struct user_namespace, ns);
+ if (user_ns == &init_user_ns) {
+ err = -EPERM;
+ goto out_fput;
+ }
+ kattr->mnt_user_ns = get_user_ns(user_ns);
+
+out_fput:
+ fput(file);
+ return err;
+}
+
+static int build_mount_kattr(const struct mount_attr *attr, size_t usize,
struct mount_kattr *kattr, unsigned int flags)
{
unsigned int lookup_flags = LOOKUP_AUTOMOUNT | LOOKUP_FOLLOW;
@@ -4028,7 +4139,13 @@ static int build_mount_kattr(const struct mount_attr *attr,
}
}
- return 0;
+ return build_mount_idmapped(attr, usize, kattr, flags);
+}
+
+static void finish_mount_kattr(struct mount_kattr *kattr)
+{
+ put_user_ns(kattr->mnt_user_ns);
+ kattr->mnt_user_ns = NULL;
}
SYSCALL_DEFINE5(mount_setattr, int, dfd, const char __user *, path, unsigned int, flags,
@@ -4060,7 +4177,7 @@ SYSCALL_DEFINE5(mount_setattr, int, dfd, const char __user *, path, unsigned int
if (attr.attr_set == 0 && attr.attr_clr == 0 && attr.propagation == 0)
return 0;
- err = build_mount_kattr(&attr, &kattr, flags);
+ err = build_mount_kattr(&attr, usize, &kattr, flags);
if (err)
return err;
@@ -4069,6 +4186,7 @@ SYSCALL_DEFINE5(mount_setattr, int, dfd, const char __user *, path, unsigned int
return err;
err = do_mount_setattr(&target, &kattr);
+ finish_mount_kattr(&kattr);
path_put(&target);
return err;
}
diff --git a/fs/proc_namespace.c b/fs/proc_namespace.c
index e59d4bb3a89e..71ab9497feb3 100644
--- a/fs/proc_namespace.c
+++ b/fs/proc_namespace.c
@@ -79,6 +79,9 @@ static void show_mnt_opts(struct seq_file *m, struct vfsmount *mnt)
if (mnt->mnt_flags & fs_infop->flag)
seq_puts(m, fs_infop->str);
}
+
+ if (mnt_user_ns(mnt) != &init_user_ns)
+ seq_puts(m, ",idmapped");
}
static inline void mangle(struct seq_file *m, const char *s)
diff --git a/include/linux/fs.h b/include/linux/fs.h
index c7f9ba689145..b88ce1b2c87a 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2293,7 +2293,7 @@ struct file_system_type {
#define FS_HAS_SUBTYPE 4
#define FS_USERNS_MOUNT 8 /* Can be mounted by userns root */
#define FS_DISALLOW_NOTIFY_PERM 16 /* Disable fanotify permission events */
-#define FS_ALLOW_IDMAP 32 /* FS has been updated to handle vfs idmappings. */
+#define FS_ALLOW_IDMAP 32 /* FS has been updated to handle vfs idmappings. */
#define FS_THP_SUPPORT 8192 /* Remove once all fs converted */
#define FS_RENAME_DOES_D_MOVE 32768 /* FS will handle d_move() during rename() internally. */
int (*init_fs_context)(struct fs_context *);
diff --git a/include/linux/mount.h b/include/linux/mount.h
index d0d4a270acea..f87811045aec 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -77,7 +77,8 @@ struct vfsmount {
static inline struct user_namespace *mnt_user_ns(const struct vfsmount *mnt)
{
- return READ_ONCE(mnt->mnt_user_ns);
+ /* Pairs with smp_store_release() in do_idmap_mount(). */
+ return smp_load_acquire(&mnt->mnt_user_ns);
}
struct file; /* forward dec */
diff --git a/include/uapi/linux/mount.h b/include/uapi/linux/mount.h
index fba42b4bfc1c..66422a58f061 100644
--- a/include/uapi/linux/mount.h
+++ b/include/uapi/linux/mount.h
@@ -119,6 +119,7 @@ enum fsconfig_command {
#define MOUNT_ATTR_NOATIME 0x00000010 /* - Do not update access times. */
#define MOUNT_ATTR_STRICTATIME 0x00000020 /* - Always perform atime updates */
#define MOUNT_ATTR_NODIRATIME 0x00000080 /* Do not update directory access times */
+#define MOUNT_ATTR_IDMAP 0x00100000 /* Idmap this mount to @userns in mount_attr. */
/*
* mount_setattr()
@@ -127,6 +128,7 @@ struct mount_attr {
__u64 attr_set;
__u64 attr_clr;
__u64 propagation;
+ __u64 userns_fd;
};
/* Change propagation through mount_setattr(). */
@@ -140,6 +142,7 @@ enum propagation_type {
/* List of all mount_attr versions. */
#define MOUNT_ATTR_SIZE_VER0 24 /* sizeof first published struct */
-#define MOUNT_ATTR_SIZE_LATEST MOUNT_ATTR_SIZE_VER0
+#define MOUNT_ATTR_SIZE_VER1 32 /* sizeof second published struct */
+#define MOUNT_ATTR_SIZE_LATEST MOUNT_ATTR_SIZE_VER1
#endif /* _UAPI_LINUX_MOUNT_H */
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* [PATCH v3 37/38] tests: extend mount_setattr tests
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (34 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 36/38] fs: introduce MOUNT_ATTR_IDMAP Christian Brauner
@ 2020-11-28 21:35 ` Christian Brauner
2020-11-28 22:54 ` [PATCH v3 00/38] idmapped mounts Serge E. Hallyn
36 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-11-28 21:35 UTC (permalink / raw)
To: Alexander Viro, Christoph Hellwig, linux-fsdevel
Cc: John Johansen, James Morris, Mimi Zohar, Dmitry Kasatkin,
Stephen Smalley, Casey Schaufler, Arnd Bergmann, Andreas Dilger,
OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel, Josh Triplett,
Andy Lutomirski, Theodore Tso, Alban Crequy, Tycho Andersen,
David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux, Christian Brauner, Christoph Hellwig
Extend the mount_setattr test-suite to include tests for idmapped mounts. Note,
the main test-suite ist part of xfstests and is pretty huge. These tests here
just make sure that the syscalls bits work correctly.
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---
/* v2 */
patch introduced
/* v3 */
- Christoph Hellwig <hch@lst.de>, Darrick J. Wong <darrick.wong@oracle.com>:
- Port main test-suite to xfstests.
---
.../mount_setattr/mount_setattr_test.c | 483 ++++++++++++++++++
1 file changed, 483 insertions(+)
diff --git a/tools/testing/selftests/mount_setattr/mount_setattr_test.c b/tools/testing/selftests/mount_setattr/mount_setattr_test.c
index d940356ab277..9ac898b2eb33 100644
--- a/tools/testing/selftests/mount_setattr/mount_setattr_test.c
+++ b/tools/testing/selftests/mount_setattr/mount_setattr_test.c
@@ -108,15 +108,57 @@ struct mount_attr {
__u64 attr_set;
__u64 attr_clr;
__u64 propagation;
+ __u64 userns_fd;
};
#endif
+#ifndef __NR_open_tree
+ #if defined __alpha__
+ #define __NR_open_tree 538
+ #elif defined _MIPS_SIM
+ #if _MIPS_SIM == _MIPS_SIM_ABI32 /* o32 */
+ #define __NR_open_tree 4428
+ #endif
+ #if _MIPS_SIM == _MIPS_SIM_NABI32 /* n32 */
+ #define __NR_open_tree 6428
+ #endif
+ #if _MIPS_SIM == _MIPS_SIM_ABI64 /* n64 */
+ #define __NR_open_tree 5428
+ #endif
+ #elif defined __ia64__
+ #define __NR_open_tree (428 + 1024)
+ #else
+ #define __NR_open_tree 428
+ #endif
+#endif
+
+#ifndef MOUNT_ATTR_IDMAP
+#define MOUNT_ATTR_IDMAP 0x00100000
+#endif
+
static inline int sys_mount_setattr(int dfd, const char *path, unsigned int flags,
struct mount_attr *attr, size_t size)
{
return syscall(__NR_mount_setattr, dfd, path, flags, attr, size);
}
+#ifndef OPEN_TREE_CLONE
+#define OPEN_TREE_CLONE 1
+#endif
+
+#ifndef OPEN_TREE_CLOEXEC
+#define OPEN_TREE_CLOEXEC O_CLOEXEC
+#endif
+
+#ifndef AT_RECURSIVE
+#define AT_RECURSIVE 0x8000 /* Apply to the entire subtree */
+#endif
+
+static inline int sys_open_tree(int dfd, const char *filename, unsigned int flags)
+{
+ return syscall(__NR_open_tree, dfd, filename, flags);
+}
+
static ssize_t write_nointr(int fd, const void *buf, size_t count)
{
ssize_t ret;
@@ -938,4 +980,445 @@ TEST_F(mount_setattr, wrong_mount_namespace)
ASSERT_EQ(errno, EINVAL);
}
+FIXTURE(mount_setattr_idmapped) {
+};
+
+FIXTURE_SETUP(mount_setattr_idmapped)
+{
+ int img_fd = -EBADF;
+
+ ASSERT_EQ(unshare(CLONE_NEWNS), 0);
+
+ ASSERT_EQ(mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, 0), 0);
+
+ (void)umount2("/mnt", MNT_DETACH);
+ (void)umount2("/tmp", MNT_DETACH);
+
+ ASSERT_EQ(mount("testing", "/tmp", "tmpfs", MS_NOATIME | MS_NODEV,
+ "size=100000,mode=700"), 0);
+
+ ASSERT_EQ(mkdir("/tmp/B", 0777), 0);
+ ASSERT_EQ(mknodat(-EBADF, "/tmp/B/b", S_IFREG | 0644, 0), 0);
+ ASSERT_EQ(chown("/tmp/B/b", 0, 0), 0);
+
+ ASSERT_EQ(mount("testing", "/tmp/B", "tmpfs", MS_NOATIME | MS_NODEV,
+ "size=100000,mode=700"), 0);
+
+ ASSERT_EQ(mkdir("/tmp/B/BB", 0777), 0);
+ ASSERT_EQ(mknodat(-EBADF, "/tmp/B/BB/b", S_IFREG | 0644, 0), 0);
+ ASSERT_EQ(chown("/tmp/B/BB/b", 0, 0), 0);
+
+ ASSERT_EQ(mount("testing", "/tmp/B/BB", "tmpfs", MS_NOATIME | MS_NODEV,
+ "size=100000,mode=700"), 0);
+
+ ASSERT_EQ(mount("testing", "/mnt", "tmpfs", MS_NOATIME | MS_NODEV,
+ "size=100000,mode=700"), 0);
+
+ ASSERT_EQ(mkdir("/mnt/A", 0777), 0);
+
+ ASSERT_EQ(mount("testing", "/mnt/A", "tmpfs", MS_NOATIME | MS_NODEV,
+ "size=100000,mode=700"), 0);
+
+ ASSERT_EQ(mkdir("/mnt/A/AA", 0777), 0);
+
+ ASSERT_EQ(mount("/tmp", "/mnt/A/AA", NULL, MS_BIND | MS_REC, NULL), 0);
+
+ ASSERT_EQ(mkdir("/mnt/B", 0777), 0);
+
+ ASSERT_EQ(mount("testing", "/mnt/B", "ramfs",
+ MS_NOATIME | MS_NODEV | MS_NOSUID, 0), 0);
+
+ ASSERT_EQ(mkdir("/mnt/B/BB", 0777), 0);
+
+ ASSERT_EQ(mount("testing", "/tmp/B/BB", "devpts",
+ MS_RELATIME | MS_NOEXEC | MS_RDONLY, 0), 0);
+
+ ASSERT_EQ(mkdir("/mnt/C", 0777), 0);
+ ASSERT_EQ(mkdir("/mnt/D", 0777), 0);
+ img_fd = openat(-EBADF, "/mnt/C/ext4.img", O_CREAT | O_WRONLY, 0600);
+ ASSERT_GE(img_fd, 0);
+ ASSERT_EQ(ftruncate(img_fd, 1024 * 2048), 0);
+ ASSERT_EQ(system("mkfs.ext4 -q /mnt/C/ext4.img"), 0);
+ ASSERT_EQ(system("mount -o loop -t ext4 /mnt/C/ext4.img /mnt/D/"), 0);
+ ASSERT_EQ(close(img_fd), 0);
+}
+
+FIXTURE_TEARDOWN(mount_setattr_idmapped)
+{
+ (void)umount2("/mnt/A", MNT_DETACH);
+ (void)umount2("/tmp", MNT_DETACH);
+}
+
+/**
+ * Validate that negative fd values are rejected.
+ */
+TEST_F(mount_setattr_idmapped, invalid_fd_negative)
+{
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ .userns_fd = -EBADF,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ ASSERT_NE(sys_mount_setattr(-1, "/", 0, &attr, sizeof(attr)), 0) {
+ TH_LOG("failure: created idmapped mount with negative fd");
+ }
+}
+
+/**
+ * Validate that excessively large fd values are rejected.
+ */
+TEST_F(mount_setattr_idmapped, invalid_fd_large)
+{
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ .userns_fd = INT64_MAX,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ ASSERT_NE(sys_mount_setattr(-1, "/", 0, &attr, sizeof(attr)), 0) {
+ TH_LOG("failure: created idmapped mount with too large fd value");
+ }
+}
+
+/**
+ * Validate that closed fd values are rejected.
+ */
+TEST_F(mount_setattr_idmapped, invalid_fd_closed)
+{
+ int fd;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ fd = open("/dev/null", O_RDONLY | O_CLOEXEC);
+ ASSERT_GE(fd, 0);
+ ASSERT_GE(close(fd), 0);
+
+ attr.userns_fd = fd;
+ ASSERT_NE(sys_mount_setattr(-1, "/", 0, &attr, sizeof(attr)), 0) {
+ TH_LOG("failure: created idmapped mount with closed fd");
+ }
+}
+
+/**
+ * Validate that the initial user namespace is rejected.
+ */
+TEST_F(mount_setattr_idmapped, invalid_fd_initial_userns)
+{
+ int open_tree_fd = -EBADF;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ open_tree_fd = sys_open_tree(-EBADF, "/mnt/D",
+ AT_NO_AUTOMOUNT |
+ AT_SYMLINK_NOFOLLOW |
+ OPEN_TREE_CLOEXEC | OPEN_TREE_CLONE);
+ ASSERT_GE(open_tree_fd, 0);
+
+ attr.userns_fd = open("/proc/1/ns/user", O_RDONLY | O_CLOEXEC);
+ ASSERT_GE(attr.userns_fd, 0);
+ ASSERT_NE(sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+ ASSERT_EQ(errno, EPERM);
+ ASSERT_EQ(close(attr.userns_fd), 0);
+ ASSERT_EQ(close(open_tree_fd), 0);
+}
+
+static int map_ids(pid_t pid, unsigned long nsid, unsigned long hostid,
+ unsigned long range)
+{
+ char map[100], procfile[256];
+
+ snprintf(procfile, sizeof(procfile), "/proc/%d/uid_map", pid);
+ snprintf(map, sizeof(map), "%lu %lu %lu", nsid, hostid, range);
+ if (write_file(procfile, map, strlen(map)))
+ return -1;
+
+
+ snprintf(procfile, sizeof(procfile), "/proc/%d/gid_map", pid);
+ snprintf(map, sizeof(map), "%lu %lu %lu", nsid, hostid, range);
+ if (write_file(procfile, map, strlen(map)))
+ return -1;
+
+ return 0;
+}
+
+#define __STACK_SIZE (8 * 1024 * 1024)
+static pid_t do_clone(int (*fn)(void *), void *arg, int flags)
+{
+ void *stack;
+
+ stack = malloc(__STACK_SIZE);
+ if (!stack)
+ return -ENOMEM;
+
+#ifdef __ia64__
+ return __clone2(fn, stack, __STACK_SIZE, flags | SIGCHLD, arg, NULL);
+#else
+ return clone(fn, stack + __STACK_SIZE, flags | SIGCHLD, arg, NULL);
+#endif
+}
+
+static int get_userns_fd_cb(void *data)
+{
+ return kill(getpid(), SIGSTOP);
+}
+
+static int wait_for_pid(pid_t pid)
+{
+ int status, ret;
+
+again:
+ ret = waitpid(pid, &status, 0);
+ if (ret == -1) {
+ if (errno == EINTR)
+ goto again;
+
+ return -1;
+ }
+
+ if (!WIFEXITED(status))
+ return -1;
+
+ return WEXITSTATUS(status);
+}
+
+static int get_userns_fd(unsigned long nsid, unsigned long hostid, unsigned long range)
+{
+ int ret;
+ pid_t pid;
+ char path[256];
+
+ pid = do_clone(get_userns_fd_cb, NULL, CLONE_NEWUSER);
+ if (pid < 0)
+ return -errno;
+
+ ret = map_ids(pid, nsid, hostid, range);
+ if (ret < 0)
+ return ret;
+
+ snprintf(path, sizeof(path), "/proc/%d/ns/user", pid);
+ ret = open(path, O_RDONLY | O_CLOEXEC);
+ kill(pid, SIGKILL);
+ wait_for_pid(pid);
+ return ret;
+}
+
+/**
+ * Validate that an attached mount in our mount namespace can be idmapped.
+ * (The kernel enforces that the mount's mount namespace and the caller's mount
+ * namespace match.)
+ */
+TEST_F(mount_setattr_idmapped, attached_mount_inside_current_mount_namespace)
+{
+ int open_tree_fd = -EBADF;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ open_tree_fd = sys_open_tree(-EBADF, "/mnt/D",
+ AT_EMPTY_PATH |
+ AT_NO_AUTOMOUNT |
+ AT_SYMLINK_NOFOLLOW |
+ OPEN_TREE_CLOEXEC);
+ ASSERT_GE(open_tree_fd, 0);
+
+ attr.userns_fd = get_userns_fd(0, 10000, 10000);
+ ASSERT_GE(attr.userns_fd, 0);
+ ASSERT_EQ(sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+ ASSERT_EQ(close(attr.userns_fd), 0);
+ ASSERT_EQ(close(open_tree_fd), 0);
+}
+
+/**
+ * Validate that idmapping a mount is rejected if the mount's mount namespace
+ * and our mount namespace don't match.
+ * (The kernel enforces that the mount's mount namespace and the caller's mount
+ * namespace match.)
+ */
+TEST_F(mount_setattr_idmapped, attached_mount_outside_current_mount_namespace)
+{
+ int open_tree_fd = -EBADF;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ open_tree_fd = sys_open_tree(-EBADF, "/mnt/D",
+ AT_EMPTY_PATH |
+ AT_NO_AUTOMOUNT |
+ AT_SYMLINK_NOFOLLOW |
+ OPEN_TREE_CLOEXEC);
+ ASSERT_GE(open_tree_fd, 0);
+
+ ASSERT_EQ(unshare(CLONE_NEWNS), 0);
+
+ attr.userns_fd = get_userns_fd(0, 10000, 10000);
+ ASSERT_GE(attr.userns_fd, 0);
+ ASSERT_NE(sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr,
+ sizeof(attr)), 0);
+ ASSERT_EQ(close(attr.userns_fd), 0);
+ ASSERT_EQ(close(open_tree_fd), 0);
+}
+
+/**
+ * Validate that an attached mount in our mount namespace can be idmapped.
+ */
+TEST_F(mount_setattr_idmapped, detached_mount_inside_current_mount_namespace)
+{
+ int open_tree_fd = -EBADF;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ open_tree_fd = sys_open_tree(-EBADF, "/mnt/D",
+ AT_EMPTY_PATH |
+ AT_NO_AUTOMOUNT |
+ AT_SYMLINK_NOFOLLOW |
+ OPEN_TREE_CLOEXEC |
+ OPEN_TREE_CLONE);
+ ASSERT_GE(open_tree_fd, 0);
+
+ /* Changing mount properties on a detached mount. */
+ attr.userns_fd = get_userns_fd(0, 10000, 10000);
+ ASSERT_GE(attr.userns_fd, 0);
+ ASSERT_EQ(sys_mount_setattr(open_tree_fd, "",
+ AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+ ASSERT_EQ(close(attr.userns_fd), 0);
+ ASSERT_EQ(close(open_tree_fd), 0);
+}
+
+/**
+ * Validate that a detached mount not in our mount namespace can be idmapped.
+ */
+TEST_F(mount_setattr_idmapped, detached_mount_outside_current_mount_namespace)
+{
+ int open_tree_fd = -EBADF;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ open_tree_fd = sys_open_tree(-EBADF, "/mnt/D",
+ AT_EMPTY_PATH |
+ AT_NO_AUTOMOUNT |
+ AT_SYMLINK_NOFOLLOW |
+ OPEN_TREE_CLOEXEC |
+ OPEN_TREE_CLONE);
+ ASSERT_GE(open_tree_fd, 0);
+
+ ASSERT_EQ(unshare(CLONE_NEWNS), 0);
+
+ /* Changing mount properties on a detached mount. */
+ attr.userns_fd = get_userns_fd(0, 10000, 10000);
+ ASSERT_GE(attr.userns_fd, 0);
+ ASSERT_EQ(sys_mount_setattr(open_tree_fd, "",
+ AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+ ASSERT_EQ(close(attr.userns_fd), 0);
+ ASSERT_EQ(close(open_tree_fd), 0);
+}
+
+/**
+ * Validate that currently changing the idmapping of an idmapped mount fails.
+ */
+TEST_F(mount_setattr_idmapped, change_idmapping)
+{
+ int open_tree_fd = -EBADF;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ open_tree_fd = sys_open_tree(-EBADF, "/mnt/D",
+ AT_EMPTY_PATH |
+ AT_NO_AUTOMOUNT |
+ AT_SYMLINK_NOFOLLOW |
+ OPEN_TREE_CLOEXEC |
+ OPEN_TREE_CLONE);
+ ASSERT_GE(open_tree_fd, 0);
+
+ attr.userns_fd = get_userns_fd(0, 10000, 10000);
+ ASSERT_GE(attr.userns_fd, 0);
+ ASSERT_EQ(sys_mount_setattr(open_tree_fd, "",
+ AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+ ASSERT_EQ(close(attr.userns_fd), 0);
+
+ /* Change idmapping on a detached mount that is already idmapped. */
+ attr.userns_fd = get_userns_fd(0, 20000, 10000);
+ ASSERT_GE(attr.userns_fd, 0);
+ ASSERT_NE(sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+ ASSERT_EQ(close(attr.userns_fd), 0);
+ ASSERT_EQ(close(open_tree_fd), 0);
+}
+
+static bool expected_uid_gid(int dfd, const char *path, int flags,
+ uid_t expected_uid, gid_t expected_gid)
+{
+ int ret;
+ struct stat st;
+
+ ret = fstatat(dfd, path, &st, flags);
+ if (ret < 0)
+ return false;
+
+ return st.st_uid == expected_uid && st.st_gid == expected_gid;
+}
+
+TEST_F(mount_setattr_idmapped, idmap_mount_tree_invalid)
+{
+ int open_tree_fd = -EBADF;
+ struct mount_attr attr = {
+ .attr_set = MOUNT_ATTR_IDMAP,
+ };
+
+ if (!mount_setattr_supported())
+ SKIP(return, "mount_setattr syscall not supported");
+
+ ASSERT_EQ(expected_uid_gid(-EBADF, "/tmp/B/b", 0, 0, 0), 0);
+ ASSERT_EQ(expected_uid_gid(-EBADF, "/tmp/B/BB/b", 0, 0, 0), 0);
+
+ open_tree_fd = sys_open_tree(-EBADF, "/mnt/A",
+ AT_RECURSIVE |
+ AT_EMPTY_PATH |
+ AT_NO_AUTOMOUNT |
+ AT_SYMLINK_NOFOLLOW |
+ OPEN_TREE_CLOEXEC |
+ OPEN_TREE_CLONE);
+ ASSERT_GE(open_tree_fd, 0);
+
+ attr.userns_fd = get_userns_fd(0, 10000, 10000);
+ ASSERT_GE(attr.userns_fd, 0);
+ ASSERT_NE(sys_mount_setattr(open_tree_fd, "", AT_EMPTY_PATH, &attr, sizeof(attr)), 0);
+ ASSERT_EQ(close(attr.userns_fd), 0);
+ ASSERT_EQ(close(open_tree_fd), 0);
+
+ ASSERT_EQ(expected_uid_gid(-EBADF, "/tmp/B/b", 0, 0, 0), 0);
+ ASSERT_EQ(expected_uid_gid(-EBADF, "/tmp/B/BB/b", 0, 0, 0), 0);
+ ASSERT_EQ(expected_uid_gid(open_tree_fd, "B/b", 0, 0, 0), 0);
+ ASSERT_EQ(expected_uid_gid(open_tree_fd, "B/BB/b", 0, 0, 0), 0);
+}
+
TEST_HARNESS_MAIN
--
2.29.2
^ permalink raw reply related [flat|nested] 73+ messages in thread
* Re: [PATCH v3 08/38] capability: handle idmapped mounts
2020-11-28 21:34 ` [PATCH v3 08/38] capability: handle idmapped mounts Christian Brauner
@ 2020-11-28 22:34 ` Serge E. Hallyn
0 siblings, 0 replies; 73+ messages in thread
From: Serge E. Hallyn @ 2020-11-28 22:34 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux,
Christoph Hellwig
On Sat, Nov 28, 2020 at 10:34:57PM +0100, Christian Brauner wrote:
> In order to determine whether a caller holds privilege over a given inode the
> capability framework exposes the two helpers privileged_wrt_inode_uidgid() and
> capable_wrt_inode_uidgid(). The former verifies that the inode has a mapping in
> the caller's user namespace and the latter additionally verifies that the caller
> has the requested capability in their current user namespace.
> If the inode is accessed through an idmapped mount we simply need to map it
> according to the mount's user namespace. Afterwards the checks are identical to
> non-idmapped inodes. If the initial user namespace is passed all operations are
> a nop so non-idmapped mounts will not see a change in behavior and will also not
> see any performance impact.
>
> Cc: Christoph Hellwig <hch@lst.de>
> Cc: David Howells <dhowells@redhat.com>
> Cc: Al Viro <viro@zeniv.linux.org.uk>
> Cc: linux-fsdevel@vger.kernel.org
> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
> ---
> /* v2 */
> - Christoph Hellwig <hch@lst.de>:
> - Don't pollute the vfs with additional helpers simply extend the existing
> helpers with an additional argument and switch all callers.
>
> /* v3 */
> unchanged
> ---
> fs/attr.c | 8 ++++----
> fs/exec.c | 2 +-
> fs/inode.c | 2 +-
> fs/namei.c | 13 ++++++++-----
> fs/overlayfs/super.c | 2 +-
> fs/posix_acl.c | 2 +-
> fs/xfs/xfs_ioctl.c | 2 +-
> include/linux/capability.h | 7 +++++--
> kernel/capability.c | 14 +++++++++-----
> security/commoncap.c | 5 +++--
> 10 files changed, 34 insertions(+), 23 deletions(-)
>
> diff --git a/fs/attr.c b/fs/attr.c
> index b4bbdbd4c8ca..d270f640a192 100644
> --- a/fs/attr.c
> +++ b/fs/attr.c
> @@ -23,7 +23,7 @@ static bool chown_ok(const struct inode *inode, kuid_t uid)
> if (uid_eq(current_fsuid(), inode->i_uid) &&
> uid_eq(uid, inode->i_uid))
> return true;
> - if (capable_wrt_inode_uidgid(inode, CAP_CHOWN))
> + if (capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_CHOWN))
> return true;
> if (uid_eq(inode->i_uid, INVALID_UID) &&
> ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN))
> @@ -36,7 +36,7 @@ static bool chgrp_ok(const struct inode *inode, kgid_t gid)
> if (uid_eq(current_fsuid(), inode->i_uid) &&
> (in_group_p(gid) || gid_eq(gid, inode->i_gid)))
> return true;
> - if (capable_wrt_inode_uidgid(inode, CAP_CHOWN))
> + if (capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_CHOWN))
> return true;
> if (gid_eq(inode->i_gid, INVALID_GID) &&
> ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN))
> @@ -92,7 +92,7 @@ int setattr_prepare(struct dentry *dentry, struct iattr *attr)
> /* Also check the setgid bit! */
> if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
> inode->i_gid) &&
> - !capable_wrt_inode_uidgid(inode, CAP_FSETID))
> + !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID))
> attr->ia_mode &= ~S_ISGID;
> }
>
> @@ -193,7 +193,7 @@ void setattr_copy(struct inode *inode, const struct iattr *attr)
> umode_t mode = attr->ia_mode;
>
> if (!in_group_p(inode->i_gid) &&
> - !capable_wrt_inode_uidgid(inode, CAP_FSETID))
> + !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID))
> mode &= ~S_ISGID;
> inode->i_mode = mode;
> }
> diff --git a/fs/exec.c b/fs/exec.c
> index 547a2390baf5..8e75d7a33514 100644
> --- a/fs/exec.c
> +++ b/fs/exec.c
> @@ -1398,7 +1398,7 @@ void would_dump(struct linux_binprm *bprm, struct file *file)
> /* Ensure mm->user_ns contains the executable */
> user_ns = old = bprm->mm->user_ns;
> while ((user_ns != &init_user_ns) &&
> - !privileged_wrt_inode_uidgid(user_ns, inode))
> + !privileged_wrt_inode_uidgid(user_ns, &init_user_ns, inode))
> user_ns = user_ns->parent;
>
> if (old != user_ns) {
> diff --git a/fs/inode.c b/fs/inode.c
> index 9d78c37b00b8..7a15372d9c2d 100644
> --- a/fs/inode.c
> +++ b/fs/inode.c
> @@ -2147,7 +2147,7 @@ void inode_init_owner(struct inode *inode, const struct inode *dir,
> mode |= S_ISGID;
> else if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP) &&
> !in_group_p(inode->i_gid) &&
> - !capable_wrt_inode_uidgid(dir, CAP_FSETID))
> + !capable_wrt_inode_uidgid(&init_user_ns, dir, CAP_FSETID))
> mode &= ~S_ISGID;
> } else
> inode->i_gid = current_fsgid();
> diff --git a/fs/namei.c b/fs/namei.c
> index d4a6dd772303..3f52730af6c5 100644
> --- a/fs/namei.c
> +++ b/fs/namei.c
> @@ -357,10 +357,11 @@ int generic_permission(struct inode *inode, int mask)
> if (S_ISDIR(inode->i_mode)) {
> /* DACs are overridable for directories */
> if (!(mask & MAY_WRITE))
> - if (capable_wrt_inode_uidgid(inode,
> + if (capable_wrt_inode_uidgid(&init_user_ns, inode,
> CAP_DAC_READ_SEARCH))
> return 0;
> - if (capable_wrt_inode_uidgid(inode, CAP_DAC_OVERRIDE))
> + if (capable_wrt_inode_uidgid(&init_user_ns, inode,
> + CAP_DAC_OVERRIDE))
> return 0;
> return -EACCES;
> }
> @@ -370,7 +371,8 @@ int generic_permission(struct inode *inode, int mask)
> */
> mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
> if (mask == MAY_READ)
> - if (capable_wrt_inode_uidgid(inode, CAP_DAC_READ_SEARCH))
> + if (capable_wrt_inode_uidgid(&init_user_ns, inode,
> + CAP_DAC_READ_SEARCH))
> return 0;
> /*
> * Read/write DACs are always overridable.
> @@ -378,7 +380,8 @@ int generic_permission(struct inode *inode, int mask)
> * at least one exec bit set.
> */
> if (!(mask & MAY_EXEC) || (inode->i_mode & S_IXUGO))
> - if (capable_wrt_inode_uidgid(inode, CAP_DAC_OVERRIDE))
> + if (capable_wrt_inode_uidgid(&init_user_ns, inode,
> + CAP_DAC_OVERRIDE))
> return 0;
>
> return -EACCES;
> @@ -2657,7 +2660,7 @@ int __check_sticky(struct inode *dir, struct inode *inode)
> return 0;
> if (uid_eq(dir->i_uid, fsuid))
> return 0;
> - return !capable_wrt_inode_uidgid(inode, CAP_FOWNER);
> + return !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FOWNER);
> }
> EXPORT_SYMBOL(__check_sticky);
>
> diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
> index 290983bcfbb3..196fe3e3f02b 100644
> --- a/fs/overlayfs/super.c
> +++ b/fs/overlayfs/super.c
> @@ -972,7 +972,7 @@ ovl_posix_acl_xattr_set(const struct xattr_handler *handler,
> if (unlikely(inode->i_mode & S_ISGID) &&
> handler->flags == ACL_TYPE_ACCESS &&
> !in_group_p(inode->i_gid) &&
> - !capable_wrt_inode_uidgid(inode, CAP_FSETID)) {
> + !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID)) {
> struct iattr iattr = { .ia_valid = ATTR_KILL_SGID };
>
> err = ovl_setattr(dentry, &iattr);
> diff --git a/fs/posix_acl.c b/fs/posix_acl.c
> index 95882b3f5f62..4ca6d53c6f0a 100644
> --- a/fs/posix_acl.c
> +++ b/fs/posix_acl.c
> @@ -656,7 +656,7 @@ int posix_acl_update_mode(struct inode *inode, umode_t *mode_p,
> if (error == 0)
> *acl = NULL;
> if (!in_group_p(inode->i_gid) &&
> - !capable_wrt_inode_uidgid(inode, CAP_FSETID))
> + !capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_FSETID))
> mode &= ~S_ISGID;
> *mode_p = mode;
> return 0;
> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
> index 3fbd98f61ea5..97bd29fc8c43 100644
> --- a/fs/xfs/xfs_ioctl.c
> +++ b/fs/xfs/xfs_ioctl.c
> @@ -1502,7 +1502,7 @@ xfs_ioctl_setattr(
> */
>
> if ((VFS_I(ip)->i_mode & (S_ISUID|S_ISGID)) &&
> - !capable_wrt_inode_uidgid(VFS_I(ip), CAP_FSETID))
> + !capable_wrt_inode_uidgid(&init_user_ns, VFS_I(ip), CAP_FSETID))
> VFS_I(ip)->i_mode &= ~(S_ISUID|S_ISGID);
>
> /* Change the ownerships and register project quota modifications */
> diff --git a/include/linux/capability.h b/include/linux/capability.h
> index 1e7fe311cabe..041e336f3369 100644
> --- a/include/linux/capability.h
> +++ b/include/linux/capability.h
> @@ -247,8 +247,11 @@ static inline bool ns_capable_setid(struct user_namespace *ns, int cap)
> return true;
> }
> #endif /* CONFIG_MULTIUSER */
> -extern bool privileged_wrt_inode_uidgid(struct user_namespace *ns, const struct inode *inode);
> -extern bool capable_wrt_inode_uidgid(const struct inode *inode, int cap);
> +extern bool privileged_wrt_inode_uidgid(struct user_namespace *ns,
> + struct user_namespace *mnt_user_ns,
> + const struct inode *inode);
> +extern bool capable_wrt_inode_uidgid(struct user_namespace *mnt_user_ns,
> + const struct inode *inode, int cap);
> extern bool file_ns_capable(const struct file *file, struct user_namespace *ns, int cap);
> extern bool ptracer_capable(struct task_struct *tsk, struct user_namespace *ns);
> static inline bool perfmon_capable(void)
> diff --git a/kernel/capability.c b/kernel/capability.c
> index de7eac903a2a..28e3a599ff7a 100644
> --- a/kernel/capability.c
> +++ b/kernel/capability.c
> @@ -484,10 +484,12 @@ EXPORT_SYMBOL(file_ns_capable);
> *
> * Return true if the inode uid and gid are within the namespace.
> */
> -bool privileged_wrt_inode_uidgid(struct user_namespace *ns, const struct inode *inode)
> +bool privileged_wrt_inode_uidgid(struct user_namespace *ns,
> + struct user_namespace *mnt_user_ns,
> + const struct inode *inode)
> {
> - return kuid_has_mapping(ns, inode->i_uid) &&
> - kgid_has_mapping(ns, inode->i_gid);
> + return kuid_has_mapping(ns, i_uid_into_mnt(mnt_user_ns, inode)) &&
> + kgid_has_mapping(ns, i_gid_into_mnt(mnt_user_ns, inode));
> }
>
> /**
> @@ -499,11 +501,13 @@ bool privileged_wrt_inode_uidgid(struct user_namespace *ns, const struct inode *
> * its own user namespace and that the given inode's uid and gid are
> * mapped into the current user namespace.
> */
> -bool capable_wrt_inode_uidgid(const struct inode *inode, int cap)
> +bool capable_wrt_inode_uidgid(struct user_namespace *mnt_user_ns,
> + const struct inode *inode, int cap)
> {
> struct user_namespace *ns = current_user_ns();
>
> - return ns_capable(ns, cap) && privileged_wrt_inode_uidgid(ns, inode);
> + return ns_capable(ns, cap) &&
> + privileged_wrt_inode_uidgid(ns, mnt_user_ns, inode);
> }
> EXPORT_SYMBOL(capable_wrt_inode_uidgid);
>
> diff --git a/security/commoncap.c b/security/commoncap.c
> index 59bf3c1674c8..4cd2bdfd0a8b 100644
> --- a/security/commoncap.c
> +++ b/security/commoncap.c
> @@ -489,7 +489,7 @@ int cap_convert_nscap(struct dentry *dentry, void **ivalue, size_t size)
> return -EINVAL;
> if (!validheader(size, cap))
> return -EINVAL;
> - if (!capable_wrt_inode_uidgid(inode, CAP_SETFCAP))
> + if (!capable_wrt_inode_uidgid(&init_user_ns, inode, CAP_SETFCAP))
> return -EPERM;
> if (size == XATTR_CAPS_SZ_2)
> if (ns_capable(inode->i_sb->s_user_ns, CAP_SETFCAP))
> @@ -957,7 +957,8 @@ int cap_inode_removexattr(struct dentry *dentry, const char *name)
> struct inode *inode = d_backing_inode(dentry);
> if (!inode)
> return -EINVAL;
> - if (!capable_wrt_inode_uidgid(inode, CAP_SETFCAP))
> + if (!capable_wrt_inode_uidgid(&init_user_ns, inode,
> + CAP_SETFCAP))
> return -EPERM;
> return 0;
> }
> --
> 2.29.2
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 09/38] namei: add idmapped mount aware permission helpers
2020-11-28 21:34 ` [PATCH v3 09/38] namei: add idmapped mount aware permission helpers Christian Brauner
@ 2020-11-28 22:47 ` Serge E. Hallyn
2020-12-01 10:58 ` Christian Brauner
2020-12-01 10:51 ` Christoph Hellwig
1 sibling, 1 reply; 73+ messages in thread
From: Serge E. Hallyn @ 2020-11-28 22:47 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux,
Christoph Hellwig
On Sat, Nov 28, 2020 at 10:34:58PM +0100, Christian Brauner wrote:
> The two helpers inode_permission() and generic_permission() are used by the vfs
> to perform basic permission checking by verifying that the caller is privileged
> over an inode. In order to handle idmapped mounts we extend the two helpers with
> an additional user namespace argument.
> On idmapped mounts the two helpers will make sure to map the inode according to
> the mount's user namespace and then peform identical permission checks to
> inode_permission() and generic_permission(). If the initial user namespace is
> passed nothing changes so non-idmapped mounts will see identical behavior as
> before.
>
> Cc: Christoph Hellwig <hch@lst.de>
> Cc: David Howells <dhowells@redhat.com>
> Cc: Al Viro <viro@zeniv.linux.org.uk>
> Cc: linux-fsdevel@vger.kernel.org
> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
But request for some comment clarification below.
> ---
> /* v2 */
> - Christoph Hellwig <hch@lst.de>:
> - Don't pollute the vfs with additional helpers simply extend the existing
> helpers with an additional argument and switch all callers.
>
> /* v3 */
> unchanged
> ---
> fs/attr.c | 3 +-
> fs/btrfs/inode.c | 2 +-
> fs/btrfs/ioctl.c | 10 ++---
> fs/ceph/inode.c | 2 +-
> fs/cifs/cifsfs.c | 2 +-
> fs/configfs/symlink.c | 2 +-
> fs/ecryptfs/inode.c | 2 +-
> fs/exec.c | 2 +-
> fs/fuse/dir.c | 4 +-
> fs/gfs2/inode.c | 2 +-
> fs/hostfs/hostfs_kern.c | 2 +-
> fs/init.c | 9 ++--
> fs/kernfs/inode.c | 2 +-
> fs/libfs.c | 7 ++-
> fs/namei.c | 68 +++++++++++++++++-------------
> fs/nfs/dir.c | 2 +-
> fs/nfsd/nfsfh.c | 2 +-
> fs/nfsd/vfs.c | 4 +-
> fs/nilfs2/inode.c | 2 +-
> fs/notify/fanotify/fanotify_user.c | 2 +-
> fs/notify/inotify/inotify_user.c | 2 +-
> fs/ocfs2/file.c | 2 +-
> fs/ocfs2/refcounttree.c | 4 +-
> fs/open.c | 10 ++---
> fs/orangefs/inode.c | 2 +-
> fs/overlayfs/file.c | 2 +-
> fs/overlayfs/inode.c | 4 +-
> fs/overlayfs/util.c | 2 +-
> fs/posix_acl.c | 17 +++++---
> fs/proc/base.c | 4 +-
> fs/proc/fd.c | 2 +-
> fs/reiserfs/xattr.c | 2 +-
> fs/remap_range.c | 2 +-
> fs/udf/file.c | 2 +-
> fs/verity/enable.c | 2 +-
> fs/xattr.c | 2 +-
> include/linux/fs.h | 4 +-
> include/linux/posix_acl.h | 4 +-
> ipc/mqueue.c | 2 +-
> kernel/bpf/inode.c | 4 +-
> kernel/cgroup/cgroup.c | 2 +-
> kernel/sys.c | 2 +-
> mm/madvise.c | 2 +-
> mm/memcontrol.c | 2 +-
> mm/mincore.c | 2 +-
> net/unix/af_unix.c | 2 +-
> 46 files changed, 122 insertions(+), 96 deletions(-)
>
> diff --git a/fs/attr.c b/fs/attr.c
> index d270f640a192..c9e29e589cec 100644
> --- a/fs/attr.c
> +++ b/fs/attr.c
> @@ -244,7 +244,8 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
> return -EPERM;
>
> if (!inode_owner_or_capable(inode)) {
> - error = inode_permission(inode, MAY_WRITE);
> + error = inode_permission(&init_user_ns, inode,
> + MAY_WRITE);
> if (error)
> return error;
> }
> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> index da58c58ef9aa..32e3bf88d4f7 100644
> --- a/fs/btrfs/inode.c
> +++ b/fs/btrfs/inode.c
> @@ -9794,7 +9794,7 @@ static int btrfs_permission(struct inode *inode, int mask)
> if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
> return -EACCES;
> }
> - return generic_permission(inode, mask);
> + return generic_permission(&init_user_ns, inode, mask);
> }
>
> static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
> diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
> index 69a384145dc6..74500c15bdc1 100644
> --- a/fs/btrfs/ioctl.c
> +++ b/fs/btrfs/ioctl.c
> @@ -910,7 +910,7 @@ static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
> BUG_ON(d_inode(victim->d_parent) != dir);
> audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
>
> - error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
> + error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> if (error)
> return error;
> if (IS_APPEND(dir))
> @@ -939,7 +939,7 @@ static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
> return -EEXIST;
> if (IS_DEADDIR(dir))
> return -ENOENT;
> - return inode_permission(dir, MAY_WRITE | MAY_EXEC);
> + return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> }
>
> /*
> @@ -2487,7 +2487,7 @@ static int btrfs_search_path_in_tree_user(struct inode *inode,
> ret = PTR_ERR(temp_inode);
> goto out_put;
> }
> - ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC);
> + ret = inode_permission(&init_user_ns, temp_inode, MAY_READ | MAY_EXEC);
> iput(temp_inode);
> if (ret) {
> ret = -EACCES;
> @@ -3017,7 +3017,7 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
> if (root == dest)
> goto out_dput;
>
> - err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
> + err = inode_permission(&init_user_ns, inode, MAY_WRITE | MAY_EXEC);
> if (err)
> goto out_dput;
> }
> @@ -3088,7 +3088,7 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
> * running and allows defrag on files open in read-only mode.
> */
> if (!capable(CAP_SYS_ADMIN) &&
> - inode_permission(inode, MAY_WRITE)) {
> + inode_permission(&init_user_ns, inode, MAY_WRITE)) {
> ret = -EPERM;
> goto out;
> }
> diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
> index 526faf4778ce..abfe42df8a1a 100644
> --- a/fs/ceph/inode.c
> +++ b/fs/ceph/inode.c
> @@ -2335,7 +2335,7 @@ int ceph_permission(struct inode *inode, int mask)
> err = ceph_do_getattr(inode, CEPH_CAP_AUTH_SHARED, false);
>
> if (!err)
> - err = generic_permission(inode, mask);
> + err = generic_permission(&init_user_ns, inode, mask);
> return err;
> }
>
> diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
> index 472cb7777e3e..f79dbc581eee 100644
> --- a/fs/cifs/cifsfs.c
> +++ b/fs/cifs/cifsfs.c
> @@ -316,7 +316,7 @@ static int cifs_permission(struct inode *inode, int mask)
> on the client (above and beyond ACL on servers) for
> servers which do not support setting and viewing mode bits,
> so allowing client to check permissions is useful */
> - return generic_permission(inode, mask);
> + return generic_permission(&init_user_ns, inode, mask);
> }
>
> static struct kmem_cache *cifs_inode_cachep;
> diff --git a/fs/configfs/symlink.c b/fs/configfs/symlink.c
> index cb61467478ca..0b592c55f38e 100644
> --- a/fs/configfs/symlink.c
> +++ b/fs/configfs/symlink.c
> @@ -197,7 +197,7 @@ int configfs_symlink(struct inode *dir, struct dentry *dentry, const char *symna
> if (dentry->d_inode || d_unhashed(dentry))
> ret = -EEXIST;
> else
> - ret = inode_permission(dir, MAY_WRITE | MAY_EXEC);
> + ret = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> if (!ret)
> ret = type->ct_item_ops->allow_link(parent_item, target_item);
> if (!ret) {
> diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
> index e23752d9a79f..9b1ae410983c 100644
> --- a/fs/ecryptfs/inode.c
> +++ b/fs/ecryptfs/inode.c
> @@ -864,7 +864,7 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
> static int
> ecryptfs_permission(struct inode *inode, int mask)
> {
> - return inode_permission(ecryptfs_inode_to_lower(inode), mask);
> + return inode_permission(&init_user_ns, ecryptfs_inode_to_lower(inode), mask);
> }
>
> /**
> diff --git a/fs/exec.c b/fs/exec.c
> index 8e75d7a33514..b499a1a03934 100644
> --- a/fs/exec.c
> +++ b/fs/exec.c
> @@ -1391,7 +1391,7 @@ EXPORT_SYMBOL(begin_new_exec);
> void would_dump(struct linux_binprm *bprm, struct file *file)
> {
> struct inode *inode = file_inode(file);
> - if (inode_permission(inode, MAY_READ) < 0) {
> + if (inode_permission(&init_user_ns, inode, MAY_READ) < 0) {
> struct user_namespace *old, *user_ns;
> bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
>
> diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
> index ff7dbeb16f88..7ce7baed3f4f 100644
> --- a/fs/fuse/dir.c
> +++ b/fs/fuse/dir.c
> @@ -1254,7 +1254,7 @@ static int fuse_permission(struct inode *inode, int mask)
> }
>
> if (fc->default_permissions) {
> - err = generic_permission(inode, mask);
> + err = generic_permission(&init_user_ns, inode, mask);
>
> /* If permission is denied, try to refresh file
> attributes. This is also needed, because the root
> @@ -1262,7 +1262,7 @@ static int fuse_permission(struct inode *inode, int mask)
> if (err == -EACCES && !refreshed) {
> err = fuse_perm_getattr(inode, mask);
> if (!err)
> - err = generic_permission(inode, mask);
> + err = generic_permission(&init_user_ns, inode, mask);
> }
>
> /* Note: the opposite of the above test does not
> diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
> index 077ccb1b3ccc..8445588b58a6 100644
> --- a/fs/gfs2/inode.c
> +++ b/fs/gfs2/inode.c
> @@ -1851,7 +1851,7 @@ int gfs2_permission(struct inode *inode, int mask)
> if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
> error = -EPERM;
> else
> - error = generic_permission(inode, mask);
> + error = generic_permission(&init_user_ns, inode, mask);
> if (gfs2_holder_initialized(&i_gh))
> gfs2_glock_dq_uninit(&i_gh);
>
> diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
> index c070c0d8e3e9..36da0c31d053 100644
> --- a/fs/hostfs/hostfs_kern.c
> +++ b/fs/hostfs/hostfs_kern.c
> @@ -779,7 +779,7 @@ static int hostfs_permission(struct inode *ino, int desired)
> err = access_file(name, r, w, x);
> __putname(name);
> if (!err)
> - err = generic_permission(ino, desired);
> + err = generic_permission(&init_user_ns, ino, desired);
> return err;
> }
>
> diff --git a/fs/init.c b/fs/init.c
> index e9c320a48cf1..2b4842f4802b 100644
> --- a/fs/init.c
> +++ b/fs/init.c
> @@ -49,7 +49,8 @@ int __init init_chdir(const char *filename)
> error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
> if (error)
> return error;
> - error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> + error = inode_permission(&init_user_ns, path.dentry->d_inode,
> + MAY_EXEC | MAY_CHDIR);
> if (!error)
> set_fs_pwd(current->fs, &path);
> path_put(&path);
> @@ -64,7 +65,8 @@ int __init init_chroot(const char *filename)
> error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
> if (error)
> return error;
> - error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> + error = inode_permission(&init_user_ns, path.dentry->d_inode,
> + MAY_EXEC | MAY_CHDIR);
> if (error)
> goto dput_and_out;
> error = -EPERM;
> @@ -118,7 +120,8 @@ int __init init_eaccess(const char *filename)
> error = kern_path(filename, LOOKUP_FOLLOW, &path);
> if (error)
> return error;
> - error = inode_permission(d_inode(path.dentry), MAY_ACCESS);
> + error = inode_permission(&init_user_ns, d_inode(path.dentry),
> + MAY_ACCESS);
> path_put(&path);
> return error;
> }
> diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
> index fc2469a20fed..ff5598cc1de0 100644
> --- a/fs/kernfs/inode.c
> +++ b/fs/kernfs/inode.c
> @@ -285,7 +285,7 @@ int kernfs_iop_permission(struct inode *inode, int mask)
> kernfs_refresh_inode(kn, inode);
> mutex_unlock(&kernfs_mutex);
>
> - return generic_permission(inode, mask);
> + return generic_permission(&init_user_ns, inode, mask);
> }
>
> int kernfs_xattr_get(struct kernfs_node *kn, const char *name,
> diff --git a/fs/libfs.c b/fs/libfs.c
> index fc34361c1489..23d0a00668fd 100644
> --- a/fs/libfs.c
> +++ b/fs/libfs.c
> @@ -1316,9 +1316,14 @@ static ssize_t empty_dir_listxattr(struct dentry *dentry, char *list, size_t siz
> return -EOPNOTSUPP;
> }
>
> +static int empty_dir_permission(struct inode *inode, int mask)
> +{
> + return generic_permission(&init_user_ns, inode, mask);
> +}
> +
> static const struct inode_operations empty_dir_inode_operations = {
> .lookup = empty_dir_lookup,
> - .permission = generic_permission,
> + .permission = empty_dir_permission,
> .setattr = empty_dir_setattr,
> .getattr = empty_dir_getattr,
> .listxattr = empty_dir_listxattr,
> diff --git a/fs/namei.c b/fs/namei.c
> index 3f52730af6c5..38222f92efb6 100644
> --- a/fs/namei.c
> +++ b/fs/namei.c
> @@ -259,7 +259,7 @@ void putname(struct filename *name)
> __putname(name);
> }
>
> -static int check_acl(struct inode *inode, int mask)
> +static int check_acl(struct user_namespace *user_ns, struct inode *inode, int mask)
> {
> #ifdef CONFIG_FS_POSIX_ACL
> struct posix_acl *acl;
> @@ -271,14 +271,14 @@ static int check_acl(struct inode *inode, int mask)
> /* no ->get_acl() calls in RCU mode... */
> if (is_uncached_acl(acl))
> return -ECHILD;
> - return posix_acl_permission(inode, acl, mask);
> + return posix_acl_permission(user_ns, inode, acl, mask);
> }
>
> acl = get_acl(inode, ACL_TYPE_ACCESS);
> if (IS_ERR(acl))
> return PTR_ERR(acl);
> if (acl) {
> - int error = posix_acl_permission(inode, acl, mask);
> + int error = posix_acl_permission(user_ns, inode, acl, mask);
> posix_acl_release(acl);
> return error;
> }
> @@ -293,12 +293,15 @@ static int check_acl(struct inode *inode, int mask)
> * Note that the POSIX ACL check cares about the MAY_NOT_BLOCK bit,
> * for RCU walking.
> */
> -static int acl_permission_check(struct inode *inode, int mask)
> +static int acl_permission_check(struct user_namespace *user_ns,
> + struct inode *inode, int mask)
> {
> unsigned int mode = inode->i_mode;
> + kuid_t i_uid;
>
> /* Are we the owner? If so, ACL's don't matter */
> - if (likely(uid_eq(current_fsuid(), inode->i_uid))) {
> + i_uid = i_uid_into_mnt(user_ns, inode);
> + if (likely(uid_eq(current_fsuid(), i_uid))) {
> mask &= 7;
> mode >>= 6;
> return (mask & ~mode) ? -EACCES : 0;
> @@ -306,7 +309,7 @@ static int acl_permission_check(struct inode *inode, int mask)
>
> /* Do we have ACL's? */
> if (IS_POSIXACL(inode) && (mode & S_IRWXG)) {
> - int error = check_acl(inode, mask);
> + int error = check_acl(user_ns, inode, mask);
> if (error != -EAGAIN)
> return error;
> }
> @@ -320,7 +323,8 @@ static int acl_permission_check(struct inode *inode, int mask)
> * about? Need to check group ownership if so.
> */
> if (mask & (mode ^ (mode >> 3))) {
> - if (in_group_p(inode->i_gid))
> + kgid_t kgid = i_gid_into_mnt(user_ns, inode);
> + if (in_group_p(kgid))
> mode >>= 3;
> }
>
> @@ -343,25 +347,25 @@ static int acl_permission_check(struct inode *inode, int mask)
> * request cannot be satisfied (eg. requires blocking or too much complexity).
The fn header needs a very clear update
> * It would then be called again in ref-walk mode.
> */
> -int generic_permission(struct inode *inode, int mask)
> +int generic_permission(struct user_namespace *user_ns, struct inode *inode,
> + int mask)
> {
> int ret;
>
> /*
> * Do the basic permission checks.
> */
> - ret = acl_permission_check(inode, mask);
> + ret = acl_permission_check(user_ns, inode, mask);
> if (ret != -EACCES)
> return ret;
>
> if (S_ISDIR(inode->i_mode)) {
> /* DACs are overridable for directories */
> if (!(mask & MAY_WRITE))
> - if (capable_wrt_inode_uidgid(&init_user_ns, inode,
> + if (capable_wrt_inode_uidgid(user_ns, inode,
> CAP_DAC_READ_SEARCH))
> return 0;
> - if (capable_wrt_inode_uidgid(&init_user_ns, inode,
> - CAP_DAC_OVERRIDE))
> + if (capable_wrt_inode_uidgid(user_ns, inode, CAP_DAC_OVERRIDE))
> return 0;
> return -EACCES;
> }
> @@ -371,7 +375,7 @@ int generic_permission(struct inode *inode, int mask)
> */
> mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
> if (mask == MAY_READ)
> - if (capable_wrt_inode_uidgid(&init_user_ns, inode,
> + if (capable_wrt_inode_uidgid(user_ns, inode,
> CAP_DAC_READ_SEARCH))
> return 0;
> /*
> @@ -380,8 +384,7 @@ int generic_permission(struct inode *inode, int mask)
> * at least one exec bit set.
> */
> if (!(mask & MAY_EXEC) || (inode->i_mode & S_IXUGO))
> - if (capable_wrt_inode_uidgid(&init_user_ns, inode,
> - CAP_DAC_OVERRIDE))
> + if (capable_wrt_inode_uidgid(user_ns, inode, CAP_DAC_OVERRIDE))
> return 0;
>
> return -EACCES;
> @@ -394,7 +397,8 @@ EXPORT_SYMBOL(generic_permission);
> * flag in inode->i_opflags, that says "this has not special
Ditto.
> * permission function, use the fast case".
> */
> -static inline int do_inode_permission(struct inode *inode, int mask)
> +static inline int do_inode_permission(struct user_namespace *user_ns,
> + struct inode *inode, int mask)
> {
> if (unlikely(!(inode->i_opflags & IOP_FASTPERM))) {
> if (likely(inode->i_op->permission))
> @@ -405,7 +409,7 @@ static inline int do_inode_permission(struct inode *inode, int mask)
> inode->i_opflags |= IOP_FASTPERM;
> spin_unlock(&inode->i_lock);
> }
> - return generic_permission(inode, mask);
> + return generic_permission(user_ns, inode, mask);
> }
>
> /**
> @@ -430,6 +434,7 @@ static int sb_permission(struct super_block *sb, struct inode *inode, int mask)
>
> /**
> * inode_permission - Check for access rights to a given inode
> + * @userns: The user namespace the inode is seen from
This "the inode is seen from" is confusing. Is it the mnt_user_ns through
which the inode was found, or the userns of the task which sees the inode?
It must be the former, so how about something like
The user namespace of the mountpoint through which the inode was found
> * @inode: Inode to check permission on
> * @mask: Right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
> *
> @@ -439,7 +444,8 @@ static int sb_permission(struct super_block *sb, struct inode *inode, int mask)
> *
> * When checking for MAY_APPEND, MAY_WRITE must also be set in @mask.
> */
> -int inode_permission(struct inode *inode, int mask)
> +int inode_permission(struct user_namespace *user_ns,
> + struct inode *inode, int mask)
> {
> int retval;
>
> @@ -463,7 +469,7 @@ int inode_permission(struct inode *inode, int mask)
> return -EACCES;
> }
>
> - retval = do_inode_permission(inode, mask);
> + retval = do_inode_permission(user_ns, inode, mask);
> if (retval)
> return retval;
>
> @@ -1009,7 +1015,7 @@ static bool safe_hardlink_source(struct inode *inode)
> return false;
>
> /* Hardlinking to unreadable or unwritable sources is dangerous. */
> - if (inode_permission(inode, MAY_READ | MAY_WRITE))
> + if (inode_permission(&init_user_ns, inode, MAY_READ | MAY_WRITE))
> return false;
>
> return true;
> @@ -1569,13 +1575,14 @@ static struct dentry *lookup_slow(const struct qstr *name,
> static inline int may_lookup(struct nameidata *nd)
> {
> if (nd->flags & LOOKUP_RCU) {
> - int err = inode_permission(nd->inode, MAY_EXEC|MAY_NOT_BLOCK);
> + int err = inode_permission(&init_user_ns, nd->inode,
> + MAY_EXEC | MAY_NOT_BLOCK);
> if (err != -ECHILD)
> return err;
> if (unlazy_walk(nd))
> return -ECHILD;
> }
> - return inode_permission(nd->inode, MAY_EXEC);
> + return inode_permission(&init_user_ns, nd->inode, MAY_EXEC);
> }
>
> static int reserve_stack(struct nameidata *nd, struct path *link, unsigned seq)
> @@ -2507,7 +2514,7 @@ static int lookup_one_len_common(const char *name, struct dentry *base,
> return err;
> }
>
> - return inode_permission(base->d_inode, MAY_EXEC);
> + return inode_permission(&init_user_ns, base->d_inode, MAY_EXEC);
> }
>
> /**
> @@ -2701,7 +2708,7 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
>
> audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
>
> - error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
> + error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> if (error)
> return error;
> if (IS_APPEND(dir))
> @@ -2745,7 +2752,7 @@ static inline int may_create(struct inode *dir, struct dentry *child)
> if (!kuid_has_mapping(s_user_ns, current_fsuid()) ||
> !kgid_has_mapping(s_user_ns, current_fsgid()))
> return -EOVERFLOW;
> - return inode_permission(dir, MAY_WRITE | MAY_EXEC);
> + return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> }
>
> /*
> @@ -2875,7 +2882,7 @@ static int may_open(const struct path *path, int acc_mode, int flag)
> break;
> }
>
> - error = inode_permission(inode, MAY_OPEN | acc_mode);
> + error = inode_permission(&init_user_ns, inode, MAY_OPEN | acc_mode);
> if (error)
> return error;
>
> @@ -2937,7 +2944,8 @@ static int may_o_create(const struct path *dir, struct dentry *dentry, umode_t m
> !kgid_has_mapping(s_user_ns, current_fsgid()))
> return -EOVERFLOW;
>
> - error = inode_permission(dir->dentry->d_inode, MAY_WRITE | MAY_EXEC);
> + error = inode_permission(&init_user_ns, dir->dentry->d_inode,
> + MAY_WRITE | MAY_EXEC);
> if (error)
> return error;
>
> @@ -3274,7 +3282,7 @@ struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag)
> int error;
>
> /* we want directory to be writable */
> - error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
> + error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> if (error)
> goto out_err;
> error = -EOPNOTSUPP;
> @@ -4265,12 +4273,12 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
> */
> if (new_dir != old_dir) {
> if (is_dir) {
> - error = inode_permission(source, MAY_WRITE);
> + error = inode_permission(&init_user_ns, source, MAY_WRITE);
> if (error)
> return error;
> }
> if ((flags & RENAME_EXCHANGE) && new_is_dir) {
> - error = inode_permission(target, MAY_WRITE);
> + error = inode_permission(&init_user_ns, target, MAY_WRITE);
> if (error)
> return error;
> }
> diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
> index 4e011adaf967..170ecc575519 100644
> --- a/fs/nfs/dir.c
> +++ b/fs/nfs/dir.c
> @@ -2788,7 +2788,7 @@ int nfs_permission(struct inode *inode, int mask)
>
> res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
> if (res == 0)
> - res = generic_permission(inode, mask);
> + res = generic_permission(&init_user_ns, inode, mask);
> goto out;
> }
> EXPORT_SYMBOL_GPL(nfs_permission);
> diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c
> index c81dbbad8792..380f0f74740c 100644
> --- a/fs/nfsd/nfsfh.c
> +++ b/fs/nfsd/nfsfh.c
> @@ -40,7 +40,7 @@ static int nfsd_acceptable(void *expv, struct dentry *dentry)
> /* make sure parents give x permission to user */
> int err;
> parent = dget_parent(tdentry);
> - err = inode_permission(d_inode(parent), MAY_EXEC);
> + err = inode_permission(&init_user_ns, d_inode(parent), MAY_EXEC);
> if (err < 0) {
> dput(parent);
> break;
> diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> index 1ecaceebee13..3cad79c3b441 100644
> --- a/fs/nfsd/vfs.c
> +++ b/fs/nfsd/vfs.c
> @@ -2380,13 +2380,13 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
> return 0;
>
> /* This assumes NFSD_MAY_{READ,WRITE,EXEC} == MAY_{READ,WRITE,EXEC} */
> - err = inode_permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC));
> + err = inode_permission(&init_user_ns, inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC));
>
> /* Allow read access to binaries even when mode 111 */
> if (err == -EACCES && S_ISREG(inode->i_mode) &&
> (acc == (NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE) ||
> acc == (NFSD_MAY_READ | NFSD_MAY_READ_IF_EXEC)))
> - err = inode_permission(inode, MAY_EXEC);
> + err = inode_permission(&init_user_ns, inode, MAY_EXEC);
>
> return err? nfserrno(err) : 0;
> }
> diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
> index 745d371d6fea..b6517220cad5 100644
> --- a/fs/nilfs2/inode.c
> +++ b/fs/nilfs2/inode.c
> @@ -851,7 +851,7 @@ int nilfs_permission(struct inode *inode, int mask)
> root->cno != NILFS_CPTREE_CURRENT_CNO)
> return -EROFS; /* snapshot is not writable */
>
> - return generic_permission(inode, mask);
> + return generic_permission(&init_user_ns, inode, mask);
> }
>
> int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh)
> diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
> index 3e01d8f2ab90..de4d01bb1d8d 100644
> --- a/fs/notify/fanotify/fanotify_user.c
> +++ b/fs/notify/fanotify/fanotify_user.c
> @@ -702,7 +702,7 @@ static int fanotify_find_path(int dfd, const char __user *filename,
> }
>
> /* you can only watch an inode if you have read permissions on it */
> - ret = inode_permission(path->dentry->d_inode, MAY_READ);
> + ret = inode_permission(&init_user_ns, path->dentry->d_inode, MAY_READ);
> if (ret) {
> path_put(path);
> goto out;
> diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
> index 186722ba3894..e995fd4e4e53 100644
> --- a/fs/notify/inotify/inotify_user.c
> +++ b/fs/notify/inotify/inotify_user.c
> @@ -343,7 +343,7 @@ static int inotify_find_inode(const char __user *dirname, struct path *path,
> if (error)
> return error;
> /* you can only watch an inode if you have read permissions on it */
> - error = inode_permission(path->dentry->d_inode, MAY_READ);
> + error = inode_permission(&init_user_ns, path->dentry->d_inode, MAY_READ);
> if (error) {
> path_put(path);
> return error;
> diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
> index 85979e2214b3..0c75619adf54 100644
> --- a/fs/ocfs2/file.c
> +++ b/fs/ocfs2/file.c
> @@ -1355,7 +1355,7 @@ int ocfs2_permission(struct inode *inode, int mask)
> dump_stack();
> }
>
> - ret = generic_permission(inode, mask);
> + ret = generic_permission(&init_user_ns, inode, mask);
>
> ocfs2_inode_unlock_tracker(inode, 0, &oh, had_lock);
> out:
> diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
> index 3b397fa9c9e8..c26937824be1 100644
> --- a/fs/ocfs2/refcounttree.c
> +++ b/fs/ocfs2/refcounttree.c
> @@ -4346,7 +4346,7 @@ static inline int ocfs2_may_create(struct inode *dir, struct dentry *child)
> return -EEXIST;
> if (IS_DEADDIR(dir))
> return -ENOENT;
> - return inode_permission(dir, MAY_WRITE | MAY_EXEC);
> + return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> }
>
> /**
> @@ -4400,7 +4400,7 @@ static int ocfs2_vfs_reflink(struct dentry *old_dentry, struct inode *dir,
> * file.
> */
> if (!preserve) {
> - error = inode_permission(inode, MAY_READ);
> + error = inode_permission(&init_user_ns, inode, MAY_READ);
> if (error)
> return error;
> }
> diff --git a/fs/open.c b/fs/open.c
> index 9af548fb841b..b0e8430e29f3 100644
> --- a/fs/open.c
> +++ b/fs/open.c
> @@ -83,7 +83,7 @@ long vfs_truncate(const struct path *path, loff_t length)
> if (error)
> goto out;
>
> - error = inode_permission(inode, MAY_WRITE);
> + error = inode_permission(&init_user_ns, inode, MAY_WRITE);
> if (error)
> goto mnt_drop_write_and_out;
>
> @@ -436,7 +436,7 @@ static long do_faccessat(int dfd, const char __user *filename, int mode, int fla
> goto out_path_release;
> }
>
> - res = inode_permission(inode, mode | MAY_ACCESS);
> + res = inode_permission(&init_user_ns, inode, mode | MAY_ACCESS);
> /* SuS v2 requires we report a read only fs too */
> if (res || !(mode & S_IWOTH) || special_file(inode->i_mode))
> goto out_path_release;
> @@ -492,7 +492,7 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename)
> if (error)
> goto out;
>
> - error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> + error = inode_permission(&init_user_ns, path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> if (error)
> goto dput_and_out;
>
> @@ -521,7 +521,7 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd)
> if (!d_can_lookup(f.file->f_path.dentry))
> goto out_putf;
>
> - error = inode_permission(file_inode(f.file), MAY_EXEC | MAY_CHDIR);
> + error = inode_permission(&init_user_ns, file_inode(f.file), MAY_EXEC | MAY_CHDIR);
> if (!error)
> set_fs_pwd(current->fs, &f.file->f_path);
> out_putf:
> @@ -540,7 +540,7 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename)
> if (error)
> goto out;
>
> - error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> + error = inode_permission(&init_user_ns, path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> if (error)
> goto dput_and_out;
>
> diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c
> index 48f0547d4850..4c790cc8042d 100644
> --- a/fs/orangefs/inode.c
> +++ b/fs/orangefs/inode.c
> @@ -933,7 +933,7 @@ int orangefs_permission(struct inode *inode, int mask)
> if (ret < 0)
> return ret;
>
> - return generic_permission(inode, mask);
> + return generic_permission(&init_user_ns, inode, mask);
> }
>
> int orangefs_update_time(struct inode *inode, struct timespec64 *time, int flags)
> diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
> index efccb7c1f9bc..f966b5108358 100644
> --- a/fs/overlayfs/file.c
> +++ b/fs/overlayfs/file.c
> @@ -50,7 +50,7 @@ static struct file *ovl_open_realfile(const struct file *file,
> acc_mode |= MAY_APPEND;
>
> old_cred = ovl_override_creds(inode->i_sb);
> - err = inode_permission(realinode, MAY_OPEN | acc_mode);
> + err = inode_permission(&init_user_ns, realinode, MAY_OPEN | acc_mode);
> if (err) {
> realfile = ERR_PTR(err);
> } else if (!inode_owner_or_capable(realinode)) {
> diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
> index b584dca845ba..c8e3c17ca131 100644
> --- a/fs/overlayfs/inode.c
> +++ b/fs/overlayfs/inode.c
> @@ -294,7 +294,7 @@ int ovl_permission(struct inode *inode, int mask)
> * Check overlay inode with the creds of task and underlying inode
> * with creds of mounter
> */
> - err = generic_permission(inode, mask);
> + err = generic_permission(&init_user_ns, inode, mask);
> if (err)
> return err;
>
> @@ -305,7 +305,7 @@ int ovl_permission(struct inode *inode, int mask)
> /* Make sure mounter can read file for copy up later */
> mask |= MAY_READ;
> }
> - err = inode_permission(realinode, mask);
> + err = inode_permission(&init_user_ns, realinode, mask);
> revert_creds(old_cred);
>
> return err;
> diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
> index 23f475627d07..ff67da201303 100644
> --- a/fs/overlayfs/util.c
> +++ b/fs/overlayfs/util.c
> @@ -476,7 +476,7 @@ struct file *ovl_path_open(struct path *path, int flags)
> BUG();
> }
>
> - err = inode_permission(inode, acc_mode | MAY_OPEN);
> + err = inode_permission(&init_user_ns, inode, acc_mode | MAY_OPEN);
> if (err)
> return ERR_PTR(err);
>
> diff --git a/fs/posix_acl.c b/fs/posix_acl.c
> index 4ca6d53c6f0a..5b6296cc89c4 100644
> --- a/fs/posix_acl.c
> +++ b/fs/posix_acl.c
> @@ -345,10 +345,13 @@ EXPORT_SYMBOL(posix_acl_from_mode);
> * by the acl. Returns -E... otherwise.
> */
> int
> -posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want)
> +posix_acl_permission(struct user_namespace *user_ns, struct inode *inode,
> + const struct posix_acl *acl, int want)
> {
> const struct posix_acl_entry *pa, *pe, *mask_obj;
> int found = 0;
> + kuid_t uid;
> + kgid_t gid;
>
> want &= MAY_READ | MAY_WRITE | MAY_EXEC;
>
> @@ -356,22 +359,26 @@ posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want)
> switch(pa->e_tag) {
> case ACL_USER_OBJ:
> /* (May have been checked already) */
> - if (uid_eq(inode->i_uid, current_fsuid()))
> + uid = i_uid_into_mnt(user_ns, inode);
> + if (uid_eq(uid, current_fsuid()))
> goto check_perm;
> break;
> case ACL_USER:
> - if (uid_eq(pa->e_uid, current_fsuid()))
> + uid = kuid_into_mnt(user_ns, pa->e_uid);
> + if (uid_eq(uid, current_fsuid()))
> goto mask;
> break;
> case ACL_GROUP_OBJ:
> - if (in_group_p(inode->i_gid)) {
> + gid = i_gid_into_mnt(user_ns, inode);
> + if (in_group_p(gid)) {
> found = 1;
> if ((pa->e_perm & want) == want)
> goto mask;
> }
> break;
> case ACL_GROUP:
> - if (in_group_p(pa->e_gid)) {
> + gid = kgid_into_mnt(user_ns, pa->e_gid);
> + if (in_group_p(gid)) {
> found = 1;
> if ((pa->e_perm & want) == want)
> goto mask;
> diff --git a/fs/proc/base.c b/fs/proc/base.c
> index b362523a9829..ff7259f820c8 100644
> --- a/fs/proc/base.c
> +++ b/fs/proc/base.c
> @@ -751,7 +751,7 @@ static int proc_pid_permission(struct inode *inode, int mask)
>
> return -EPERM;
> }
> - return generic_permission(inode, mask);
> + return generic_permission(&init_user_ns, inode, mask);
> }
>
>
> @@ -3489,7 +3489,7 @@ static int proc_tid_comm_permission(struct inode *inode, int mask)
> return 0;
> }
>
> - return generic_permission(inode, mask);
> + return generic_permission(&init_user_ns, inode, mask);
> }
>
> static const struct inode_operations proc_tid_comm_inode_operations = {
> diff --git a/fs/proc/fd.c b/fs/proc/fd.c
> index 81882a13212d..ad692a39381d 100644
> --- a/fs/proc/fd.c
> +++ b/fs/proc/fd.c
> @@ -299,7 +299,7 @@ int proc_fd_permission(struct inode *inode, int mask)
> struct task_struct *p;
> int rv;
>
> - rv = generic_permission(inode, mask);
> + rv = generic_permission(&init_user_ns, inode, mask);
> if (rv == 0)
> return rv;
>
> diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c
> index fe63a7c3e0da..ec440d1957a1 100644
> --- a/fs/reiserfs/xattr.c
> +++ b/fs/reiserfs/xattr.c
> @@ -957,7 +957,7 @@ int reiserfs_permission(struct inode *inode, int mask)
> if (IS_PRIVATE(inode))
> return 0;
>
> - return generic_permission(inode, mask);
> + return generic_permission(&init_user_ns, inode, mask);
> }
>
> static int xattr_hide_revalidate(struct dentry *dentry, unsigned int flags)
> diff --git a/fs/remap_range.c b/fs/remap_range.c
> index e6099beefa97..9e5b27641756 100644
> --- a/fs/remap_range.c
> +++ b/fs/remap_range.c
> @@ -438,7 +438,7 @@ static bool allow_file_dedupe(struct file *file)
> return true;
> if (uid_eq(current_fsuid(), file_inode(file)->i_uid))
> return true;
> - if (!inode_permission(file_inode(file), MAY_WRITE))
> + if (!inode_permission(&init_user_ns, file_inode(file), MAY_WRITE))
> return true;
> return false;
> }
> diff --git a/fs/udf/file.c b/fs/udf/file.c
> index ad8eefad27d7..928283925d68 100644
> --- a/fs/udf/file.c
> +++ b/fs/udf/file.c
> @@ -183,7 +183,7 @@ long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> long old_block, new_block;
> int result;
>
> - if (inode_permission(inode, MAY_READ) != 0) {
> + if (inode_permission(&init_user_ns, inode, MAY_READ) != 0) {
> udf_debug("no permission to access inode %lu\n", inode->i_ino);
> return -EPERM;
> }
> diff --git a/fs/verity/enable.c b/fs/verity/enable.c
> index 5ab3bbec8108..7449ef0050f4 100644
> --- a/fs/verity/enable.c
> +++ b/fs/verity/enable.c
> @@ -369,7 +369,7 @@ int fsverity_ioctl_enable(struct file *filp, const void __user *uarg)
> * has verity enabled, and to stabilize the data being hashed.
> */
>
> - err = inode_permission(inode, MAY_WRITE);
> + err = inode_permission(&init_user_ns, inode, MAY_WRITE);
> if (err)
> return err;
>
> diff --git a/fs/xattr.c b/fs/xattr.c
> index cd7a563e8bcd..61a9947f62f4 100644
> --- a/fs/xattr.c
> +++ b/fs/xattr.c
> @@ -131,7 +131,7 @@ xattr_permission(struct inode *inode, const char *name, int mask)
> return -EPERM;
> }
>
> - return inode_permission(inode, mask);
> + return inode_permission(&init_user_ns, inode, mask);
> }
>
> /*
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 004686f49e32..fa1137a232d1 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -2803,8 +2803,8 @@ static inline int bmap(struct inode *inode, sector_t *block)
> #endif
>
> extern int notify_change(struct dentry *, struct iattr *, struct inode **);
> -extern int inode_permission(struct inode *, int);
> -extern int generic_permission(struct inode *, int);
> +extern int inode_permission(struct user_namespace *, struct inode *, int);
> +extern int generic_permission(struct user_namespace *, struct inode *, int);
> extern int __check_sticky(struct inode *dir, struct inode *inode);
>
> static inline bool execute_ok(struct inode *inode)
> diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h
> index 90797f1b421d..8276baefed13 100644
> --- a/include/linux/posix_acl.h
> +++ b/include/linux/posix_acl.h
> @@ -15,6 +15,8 @@
> #include <linux/refcount.h>
> #include <uapi/linux/posix_acl.h>
>
> +struct user_namespace;
> +
> struct posix_acl_entry {
> short e_tag;
> unsigned short e_perm;
> @@ -62,7 +64,7 @@ posix_acl_release(struct posix_acl *acl)
> extern void posix_acl_init(struct posix_acl *, int);
> extern struct posix_acl *posix_acl_alloc(int, gfp_t);
> extern int posix_acl_valid(struct user_namespace *, const struct posix_acl *);
> -extern int posix_acl_permission(struct inode *, const struct posix_acl *, int);
> +extern int posix_acl_permission(struct user_namespace *, struct inode *, const struct posix_acl *, int);
> extern struct posix_acl *posix_acl_from_mode(umode_t, gfp_t);
> extern int posix_acl_equiv_mode(const struct posix_acl *, umode_t *);
> extern int __posix_acl_create(struct posix_acl **, gfp_t, umode_t *);
> diff --git a/ipc/mqueue.c b/ipc/mqueue.c
> index beff0cfcd1e8..693f01fe1216 100644
> --- a/ipc/mqueue.c
> +++ b/ipc/mqueue.c
> @@ -873,7 +873,7 @@ static int prepare_open(struct dentry *dentry, int oflag, int ro,
> if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY))
> return -EINVAL;
> acc = oflag2acc[oflag & O_ACCMODE];
> - return inode_permission(d_inode(dentry), acc);
> + return inode_permission(&init_user_ns, d_inode(dentry), acc);
> }
>
> static int do_mq_open(const char __user *u_name, int oflag, umode_t mode,
> diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
> index dd4b7fd60ee7..f1c393e5d47d 100644
> --- a/kernel/bpf/inode.c
> +++ b/kernel/bpf/inode.c
> @@ -507,7 +507,7 @@ static void *bpf_obj_do_get(const char __user *pathname,
> return ERR_PTR(ret);
>
> inode = d_backing_inode(path.dentry);
> - ret = inode_permission(inode, ACC_MODE(flags));
> + ret = inode_permission(&init_user_ns, inode, ACC_MODE(flags));
> if (ret)
> goto out;
>
> @@ -558,7 +558,7 @@ int bpf_obj_get_user(const char __user *pathname, int flags)
> static struct bpf_prog *__get_prog_inode(struct inode *inode, enum bpf_prog_type type)
> {
> struct bpf_prog *prog;
> - int ret = inode_permission(inode, MAY_READ);
> + int ret = inode_permission(&init_user_ns, inode, MAY_READ);
> if (ret)
> return ERR_PTR(ret);
>
> diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
> index e41c21819ba0..b13aab5a9715 100644
> --- a/kernel/cgroup/cgroup.c
> +++ b/kernel/cgroup/cgroup.c
> @@ -4673,7 +4673,7 @@ static int cgroup_may_write(const struct cgroup *cgrp, struct super_block *sb)
> if (!inode)
> return -ENOMEM;
>
> - ret = inode_permission(inode, MAY_WRITE);
> + ret = inode_permission(&init_user_ns, inode, MAY_WRITE);
> iput(inode);
> return ret;
> }
> diff --git a/kernel/sys.c b/kernel/sys.c
> index a730c03ee607..469a659c8e84 100644
> --- a/kernel/sys.c
> +++ b/kernel/sys.c
> @@ -1847,7 +1847,7 @@ static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
> if (!S_ISREG(inode->i_mode) || path_noexec(&exe.file->f_path))
> goto exit;
>
> - err = inode_permission(inode, MAY_EXEC);
> + err = inode_permission(&init_user_ns, inode, MAY_EXEC);
> if (err)
> goto exit;
>
> diff --git a/mm/madvise.c b/mm/madvise.c
> index 416a56b8e757..8afabc363b6b 100644
> --- a/mm/madvise.c
> +++ b/mm/madvise.c
> @@ -540,7 +540,7 @@ static inline bool can_do_pageout(struct vm_area_struct *vma)
> * opens a side channel.
> */
> return inode_owner_or_capable(file_inode(vma->vm_file)) ||
> - inode_permission(file_inode(vma->vm_file), MAY_WRITE) == 0;
> + inode_permission(&init_user_ns, file_inode(vma->vm_file), MAY_WRITE) == 0;
> }
>
> static long madvise_pageout(struct vm_area_struct *vma,
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 3dcbf24d2227..aed83b3ad11c 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -4906,7 +4906,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
>
> /* the process need read permission on control file */
> /* AV: shouldn't we check that it's been opened for read instead? */
> - ret = inode_permission(file_inode(cfile.file), MAY_READ);
> + ret = inode_permission(&init_user_ns, file_inode(cfile.file), MAY_READ);
> if (ret < 0)
> goto out_put_cfile;
>
> diff --git a/mm/mincore.c b/mm/mincore.c
> index 02db1a834021..d5a58e61eac6 100644
> --- a/mm/mincore.c
> +++ b/mm/mincore.c
> @@ -167,7 +167,7 @@ static inline bool can_do_mincore(struct vm_area_struct *vma)
> * mappings, which opens a side channel.
> */
> return inode_owner_or_capable(file_inode(vma->vm_file)) ||
> - inode_permission(file_inode(vma->vm_file), MAY_WRITE) == 0;
> + inode_permission(&init_user_ns, file_inode(vma->vm_file), MAY_WRITE) == 0;
> }
>
> static const struct mm_walk_ops mincore_walk_ops = {
> diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
> index 41c3303c3357..f568526d4a02 100644
> --- a/net/unix/af_unix.c
> +++ b/net/unix/af_unix.c
> @@ -936,7 +936,7 @@ static struct sock *unix_find_other(struct net *net,
> if (err)
> goto fail;
> inode = d_backing_inode(path.dentry);
> - err = inode_permission(inode, MAY_WRITE);
> + err = inode_permission(&init_user_ns, inode, MAY_WRITE);
> if (err)
> goto put_fail;
>
> --
> 2.29.2
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 00/38] idmapped mounts
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
` (35 preceding siblings ...)
2020-11-28 21:35 ` [PATCH v3 37/38] tests: extend mount_setattr tests Christian Brauner
@ 2020-11-28 22:54 ` Serge E. Hallyn
2020-12-01 10:18 ` Christian Brauner
36 siblings, 1 reply; 73+ messages in thread
From: Serge E. Hallyn @ 2020-11-28 22:54 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Sat, Nov 28, 2020 at 10:34:49PM +0100, Christian Brauner wrote:
> Hey everyone,
Hey Christian,
a general request. Argue with me if it seems misguided.
When looking at a patch or a small hunk of code, these days, if a variable
called 'ns' or 'user_ns' is seen passed to a function, it can be easy to
assume which user_ns it is based on what you think would make sense, but if
your assumption is wrong, your patch review will be wrong.
Can we stick to a convention where we have maybe
subj_userns - the userns of the task seeking some action
obj_userns - the userns of the thing being acted on - task, superblock,...
mnt_userns - the userns of a mountpoint through which an object is seen
You're replacing a lot of such callers and callsites in this patchset, so
this would be a great time to start doing that.
-serge
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 32/38] fat: handle idmapped mounts
2020-11-28 21:35 ` [PATCH v3 32/38] fat: " Christian Brauner
@ 2020-11-30 22:50 ` Mauricio Vásquez Bernal
2020-12-01 10:24 ` Christian Brauner
0 siblings, 1 reply; 73+ messages in thread
From: Mauricio Vásquez Bernal @ 2020-11-30 22:50 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel,
Andy Lutomirski, Mimi Zohar, James Bottomley, Andreas Dilger,
containers, Christoph Hellwig, Tycho Andersen, Paul Moore,
Jonathan Corbet, smbarber, linux-ext4, Mrunal Patel, Kees Cook,
Arnd Bergmann, selinux, Josh Triplett, Seth Forshee,
Aleksa Sarai, Lennart Poettering, OGAWA Hirofumi,
Geoffrey Thomas, David Howells, John Johansen, Theodore Tso,
Dmitry Kasatkin, Stephen Smalley, fstests, linux-security-module,
Eric W. Biederman, linux-api, Casey Schaufler, Alban Crequy,
linux-integrity, Todd Kjos
>
> mount2 --idmap both:1000:1001:1
>
Nit: missing arguments to mount2.
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 33/38] ext4: support idmapped mounts
2020-11-28 21:35 ` [PATCH v3 33/38] ext4: support " Christian Brauner
@ 2020-11-30 22:52 ` Mauricio Vásquez Bernal
2020-12-01 10:28 ` Christian Brauner
2020-12-01 10:54 ` Christoph Hellwig
1 sibling, 1 reply; 73+ messages in thread
From: Mauricio Vásquez Bernal @ 2020-11-30 22:52 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel,
Andy Lutomirski, Mimi Zohar, James Bottomley, Andreas Dilger,
containers, Christoph Hellwig, Tycho Andersen, Paul Moore,
Jonathan Corbet, smbarber, linux-ext4, Mrunal Patel, Kees Cook,
Arnd Bergmann, selinux, Josh Triplett, Seth Forshee,
Aleksa Sarai, Lennart Poettering, OGAWA Hirofumi,
Geoffrey Thomas, David Howells, John Johansen, Theodore Tso,
Dmitry Kasatkin, Stephen Smalley, fstests, linux-security-module,
Eric W. Biederman, linux-api, Casey Schaufler, Alban Crequy,
linux-integrity, Todd Kjos
> diff --git a/fs/ext4/Kconfig b/fs/ext4/Kconfig
> index 619dd35ddd48..5918c05cfe5b 100644
> --- a/fs/ext4/Kconfig
> +++ b/fs/ext4/Kconfig
> @@ -118,3 +118,12 @@ config EXT4_KUNIT_TESTS
> to the KUnit documentation in Documentation/dev-tools/kunit/.
>
> If unsure, say N.
> +
> +config EXT4_IDMAP_MOUNTS
> + bool "Support vfs idmapped mounts in ext4"
> + depends on EXT4_FS
> + default n
> + help
> + The vfs allows to expose a filesystem at different mountpoints with
> + differnet idmappings. Allow ext4 to be exposed through idmapped
s/differnet/different/g
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 00/38] idmapped mounts
2020-11-28 22:54 ` [PATCH v3 00/38] idmapped mounts Serge E. Hallyn
@ 2020-12-01 10:18 ` Christian Brauner
0 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-01 10:18 UTC (permalink / raw)
To: Serge E. Hallyn
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Kees Cook, Todd Kjos, Paul Moore, Jonathan Corbet,
containers, fstests, linux-security-module, linux-api,
linux-ext4, linux-integrity, selinux
On Sat, Nov 28, 2020 at 04:54:50PM -0600, Serge Hallyn wrote:
> On Sat, Nov 28, 2020 at 10:34:49PM +0100, Christian Brauner wrote:
> > Hey everyone,
>
> Hey Christian,
>
> a general request. Argue with me if it seems misguided.
>
> When looking at a patch or a small hunk of code, these days, if a variable
> called 'ns' or 'user_ns' is seen passed to a function, it can be easy to
> assume which user_ns it is based on what you think would make sense, but if
> your assumption is wrong, your patch review will be wrong.
>
> Can we stick to a convention where we have maybe
>
> subj_userns - the userns of the task seeking some action
> obj_userns - the userns of the thing being acted on - task, superblock,...
> mnt_userns - the userns of a mountpoint through which an object is seen
>
> You're replacing a lot of such callers and callsites in this patchset, so
> this would be a great time to start doing that.
Hey Serge,
this makes a lot of sense. I'll convert all accesses to the vfsmount's
userns we're introducing in this series to to mnt_userns at least.
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 32/38] fat: handle idmapped mounts
2020-11-30 22:50 ` Mauricio Vásquez Bernal
@ 2020-12-01 10:24 ` Christian Brauner
0 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-01 10:24 UTC (permalink / raw)
To: Mauricio Vásquez Bernal
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel,
Andy Lutomirski, Mimi Zohar, James Bottomley, Andreas Dilger,
containers, Christoph Hellwig, Tycho Andersen, Paul Moore,
Jonathan Corbet, smbarber, linux-ext4, Mrunal Patel, Kees Cook,
Arnd Bergmann, selinux, Josh Triplett, Seth Forshee,
Aleksa Sarai, Lennart Poettering, OGAWA Hirofumi,
Geoffrey Thomas, David Howells, John Johansen, Theodore Tso,
Dmitry Kasatkin, Stephen Smalley, fstests, linux-security-module,
Eric W. Biederman, linux-api, Casey Schaufler, Alban Crequy,
linux-integrity, Todd Kjos
On Mon, Nov 30, 2020 at 05:50:08PM -0500, Mauricio Vásquez Bernal wrote:
> >
> > mount2 --idmap both:1000:1001:1
> >
>
> Nit: missing arguments to mount2.
Thanks, fixed!
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 33/38] ext4: support idmapped mounts
2020-11-30 22:52 ` Mauricio Vásquez Bernal
@ 2020-12-01 10:28 ` Christian Brauner
0 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-01 10:28 UTC (permalink / raw)
To: Mauricio Vásquez Bernal
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel,
Andy Lutomirski, Mimi Zohar, James Bottomley, Andreas Dilger,
containers, Christoph Hellwig, Tycho Andersen, Paul Moore,
Jonathan Corbet, smbarber, linux-ext4, Mrunal Patel, Kees Cook,
Arnd Bergmann, selinux, Josh Triplett, Seth Forshee,
Aleksa Sarai, Lennart Poettering, OGAWA Hirofumi,
Geoffrey Thomas, David Howells, John Johansen, Theodore Tso,
Dmitry Kasatkin, Stephen Smalley, fstests, linux-security-module,
Eric W. Biederman, linux-api, Casey Schaufler, Alban Crequy,
linux-integrity, Todd Kjos
On Mon, Nov 30, 2020 at 05:52:04PM -0500, Mauricio Vásquez Bernal wrote:
> > diff --git a/fs/ext4/Kconfig b/fs/ext4/Kconfig
> > index 619dd35ddd48..5918c05cfe5b 100644
> > --- a/fs/ext4/Kconfig
> > +++ b/fs/ext4/Kconfig
> > @@ -118,3 +118,12 @@ config EXT4_KUNIT_TESTS
> > to the KUnit documentation in Documentation/dev-tools/kunit/.
> >
> > If unsure, say N.
> > +
> > +config EXT4_IDMAP_MOUNTS
> > + bool "Support vfs idmapped mounts in ext4"
> > + depends on EXT4_FS
> > + default n
> > + help
> > + The vfs allows to expose a filesystem at different mountpoints with
> > + differnet idmappings. Allow ext4 to be exposed through idmapped
>
> s/differnet/different/g
Fixed, thanks!
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 01/38] namespace: take lock_mount_hash() directly when changing flags
2020-11-28 21:34 ` [PATCH v3 01/38] namespace: take lock_mount_hash() directly when changing flags Christian Brauner
@ 2020-12-01 10:31 ` Christoph Hellwig
2020-12-02 9:09 ` Christian Brauner
0 siblings, 1 reply; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-01 10:31 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux,
Christoph Hellwig
Looks good,
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 02/38] mount: make {lock,unlock}_mount_hash() static
2020-11-28 21:34 ` [PATCH v3 02/38] mount: make {lock,unlock}_mount_hash() static Christian Brauner
@ 2020-12-01 10:32 ` Christoph Hellwig
2020-12-02 9:11 ` Christian Brauner
0 siblings, 1 reply; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-01 10:32 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux,
Christoph Hellwig
On Sat, Nov 28, 2020 at 10:34:51PM +0100, Christian Brauner wrote:
> The lock_mount_hash() and unlock_mount_hash() helpers are never called outside a
> single file. Remove them from the header and make them static to reflect this
> fact. There's no need to have them callable from other places right now, as
> Christoph observed.
You are spilling over the usual 73 chars for commit logs, so please check
this and the other patches.
Otherwise looks good:
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 03/38] namespace: only take read lock in do_reconfigure_mnt()
2020-11-28 21:34 ` [PATCH v3 03/38] namespace: only take read lock in do_reconfigure_mnt() Christian Brauner
@ 2020-12-01 10:32 ` Christoph Hellwig
2020-12-02 9:14 ` Christian Brauner
0 siblings, 1 reply; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-01 10:32 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux,
Christoph Hellwig
Looks good,
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 04/38] fs: add mount_setattr()
2020-11-28 21:34 ` [PATCH v3 04/38] fs: add mount_setattr() Christian Brauner
@ 2020-12-01 10:49 ` Christoph Hellwig
2020-12-02 9:42 ` Christian Brauner
0 siblings, 1 reply; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-01 10:49 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux,
Christoph Hellwig
Lots of crazy long lines in the patch. Remember that you should only
go past 80 lines if it clearly improves readability, and I don't
think it does anywhere in here.
> index a7cd0f64faa4..a5a6c470dc07 100644
> --- a/fs/internal.h
> +++ b/fs/internal.h
> @@ -82,6 +82,14 @@ int may_linkat(struct path *link);
> /*
> * namespace.c
> */
> +struct mount_kattr {
> + unsigned int attr_set;
> + unsigned int attr_clr;
> + unsigned int propagation;
> + unsigned int lookup_flags;
> + bool recurse;
> +};
Even with the whole series applied this structure is only used in
namespace.c, so it might be worth moving there.
> +static inline int mnt_hold_writers(struct mount *mnt)
> {
> - int ret = 0;
> -
> mnt->mnt.mnt_flags |= MNT_WRITE_HOLD;
> /*
> * After storing MNT_WRITE_HOLD, we'll read the counters. This store
> @@ -497,15 +495,29 @@ static int mnt_make_readonly(struct mount *mnt)
> * we're counting up here.
> */
> if (mnt_get_writers(mnt) > 0)
> - ret = -EBUSY;
> - else
> - mnt->mnt.mnt_flags |= MNT_READONLY;
> + return -EBUSY;
> +
> + return 0;
> +}
> +
> +static inline void mnt_unhold_writers(struct mount *mnt)
> +{
> /*
> * MNT_READONLY must become visible before ~MNT_WRITE_HOLD, so writers
> * that become unheld will see MNT_READONLY.
> */
> smp_wmb();
> mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD;
> +}
> +
> +static int mnt_make_readonly(struct mount *mnt)
> +{
> + int ret;
> +
> + ret = mnt_hold_writers(mnt);
> + if (!ret)
> + mnt->mnt.mnt_flags |= MNT_READONLY;
> + mnt_unhold_writers(mnt);
> return ret;
> }
>
> @@ -3438,6 +3450,33 @@ SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name,
> return ret;
> }
This refactoring seems worth a little prep patch.
>
> +static int build_attr_flags(unsigned int attr_flags, unsigned int *flags)
> +{
> + unsigned int aflags = 0;
> +
> + if (attr_flags & ~(MOUNT_ATTR_RDONLY |
> + MOUNT_ATTR_NOSUID |
> + MOUNT_ATTR_NODEV |
> + MOUNT_ATTR_NOEXEC |
> + MOUNT_ATTR__ATIME |
> + MOUNT_ATTR_NODIRATIME))
> + return -EINVAL;
> +
> + if (attr_flags & MOUNT_ATTR_RDONLY)
> + aflags |= MNT_READONLY;
> + if (attr_flags & MOUNT_ATTR_NOSUID)
> + aflags |= MNT_NOSUID;
> + if (attr_flags & MOUNT_ATTR_NODEV)
> + aflags |= MNT_NODEV;
> + if (attr_flags & MOUNT_ATTR_NOEXEC)
> + aflags |= MNT_NOEXEC;
> + if (attr_flags & MOUNT_ATTR_NODIRATIME)
> + aflags |= MNT_NODIRATIME;
> +
> + *flags = aflags;
> + return 0;
> +}
Same for adding this helper.
> + *kattr = (struct mount_kattr){
Missing whitespace before the {.
> + switch (attr->propagation) {
> + case MAKE_PROPAGATION_UNCHANGED:
> + kattr->propagation = 0;
> + break;
> + case MAKE_PROPAGATION_UNBINDABLE:
> + kattr->propagation = MS_UNBINDABLE;
> + break;
> + case MAKE_PROPAGATION_PRIVATE:
> + kattr->propagation = MS_PRIVATE;
> + break;
> + case MAKE_PROPAGATION_DEPENDENT:
> + kattr->propagation = MS_SLAVE;
> + break;
> + case MAKE_PROPAGATION_SHARED:
> + kattr->propagation = MS_SHARED;
> + break;
> + default:
Any reason to not just reuse the MS_* flags in the new API? Yes, your
new names are more descriptive, but having different names for the same
thing is also rather confusing.
> + if (upper_32_bits(attr->attr_set))
> + return -EINVAL;
> + if (build_attr_flags(lower_32_bits(attr->attr_set), &kattr->attr_set))
> + return -EINVAL;
> +
> + if (upper_32_bits(attr->attr_clr))
> + return -EINVAL;
> + if (build_attr_flags(lower_32_bits(attr->attr_clr), &kattr->attr_clr))
> + return -EINVAL;
What is so magic about the upper and lower 32 bits?
> + return -EINVAL;
> + else if ((attr->attr_clr & MOUNT_ATTR__ATIME) &&
> + ((attr->attr_clr & MOUNT_ATTR__ATIME) != MOUNT_ATTR__ATIME))
> + return -EINVAL;
No need for the else here.
That being said I'd reword the thing to be a little more obvious:
if (attr->attr_clr & MOUNT_ATTR__ATIME) {
if ((attr->attr_clr & MOUNT_ATTR__ATIME) != MOUNT_ATTR__ATIME)
return -EINVAL;
... code doing the update of the atime flags here
} else {
if (attr->attr_set & MOUNT_ATTR__ATIME)
return -EINVAL;
}
> +/* Change propagation through mount_setattr(). */
> +enum propagation_type {
> + MAKE_PROPAGATION_UNCHANGED = 0, /* Don't change mount propagation (default). */
> + MAKE_PROPAGATION_UNBINDABLE = 1, /* Make unbindable. */
> + MAKE_PROPAGATION_PRIVATE = 2, /* Do not receive or send mount events. */
> + MAKE_PROPAGATION_DEPENDENT = 3, /* Only receive mount events. */
> + MAKE_PROPAGATION_SHARED = 4, /* Send and receive mount events. */
> +};
FYI, in uapis using defines instead of enums is usually the better
choice, as that allows userspace to probe for later added defines.
But if we use MS_* here that would be void anyway.
> +/* List of all mount_attr versions. */
> +#define MOUNT_ATTR_SIZE_VER0 24 /* sizeof first published struct */
> +#define MOUNT_ATTR_SIZE_LATEST MOUNT_ATTR_SIZE_VER0
The _LATEST things is pretty dangerous as there basically is no safe
and correct way for userspace to use it.
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 06/38] fs: add id translation helpers
2020-11-28 21:34 ` [PATCH v3 06/38] fs: add id translation helpers Christian Brauner
@ 2020-12-01 10:49 ` Christoph Hellwig
2020-12-02 9:16 ` Christian Brauner
0 siblings, 1 reply; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-01 10:49 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux,
Christoph Hellwig
Looks good,
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 07/38] mount: attach mappings to mounts
2020-11-28 21:34 ` [PATCH v3 07/38] mount: attach mappings to mounts Christian Brauner
@ 2020-12-01 10:50 ` Christoph Hellwig
2020-12-01 13:25 ` Tycho Andersen
2020-12-02 9:24 ` Christian Brauner
0 siblings, 2 replies; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-01 10:50 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux,
Christoph Hellwig
The READ_ONCE still looks suspect as it generally needs to be paired
with a WRITE_ONCE. The rest looks sane to me.
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 09/38] namei: add idmapped mount aware permission helpers
2020-11-28 21:34 ` [PATCH v3 09/38] namei: add idmapped mount aware permission helpers Christian Brauner
2020-11-28 22:47 ` Serge E. Hallyn
@ 2020-12-01 10:51 ` Christoph Hellwig
2020-12-01 10:58 ` Christian Brauner
1 sibling, 1 reply; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-01 10:51 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux,
Christoph Hellwig
The subject is wrong now that there are no new helpers, just new
arguments.
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 10/38] inode: add idmapped mount aware init and permission helpers
2020-11-28 21:34 ` [PATCH v3 10/38] inode: add idmapped mount aware init and " Christian Brauner
@ 2020-12-01 10:51 ` Christoph Hellwig
2020-12-02 9:17 ` Christian Brauner
0 siblings, 1 reply; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-01 10:51 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux,
Christoph Hellwig
Same issue with the subject as for the previous patch.
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 17/38] namei: introduce struct renamedata
2020-11-28 21:35 ` [PATCH v3 17/38] namei: introduce struct renamedata Christian Brauner
@ 2020-12-01 10:53 ` Christoph Hellwig
2020-12-02 9:18 ` Christian Brauner
0 siblings, 1 reply; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-01 10:53 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux,
Christoph Hellwig
> +int vfs_rename(struct renamedata *rd)
> {
> int error;
> struct user_namespace *user_ns = &init_user_ns;
> + struct inode *old_dir = rd->old_dir, *new_dir = rd->new_dir;
> + struct dentry *old_dentry = rd->old_dentry,
> + *new_dentry = rd->new_dentry;
This looks weird. I'd just write the obvious:
struct dentry *old_dentry = rd->old_dentry;
struct dentry *new_dentry = rd->new_dentry;
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 33/38] ext4: support idmapped mounts
2020-11-28 21:35 ` [PATCH v3 33/38] ext4: support " Christian Brauner
2020-11-30 22:52 ` Mauricio Vásquez Bernal
@ 2020-12-01 10:54 ` Christoph Hellwig
2020-12-01 11:02 ` Christian Brauner
1 sibling, 1 reply; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-01 10:54 UTC (permalink / raw)
To: Christian Brauner
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux,
Christoph Hellwig
What is the reason for the config option? The only thing that it
controls is setting of a single flag.
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 09/38] namei: add idmapped mount aware permission helpers
2020-11-28 22:47 ` Serge E. Hallyn
@ 2020-12-01 10:58 ` Christian Brauner
0 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-01 10:58 UTC (permalink / raw)
To: Serge E. Hallyn
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Kees Cook, Todd Kjos, Paul Moore, Jonathan Corbet,
containers, fstests, linux-security-module, linux-api,
linux-ext4, linux-integrity, selinux, Christoph Hellwig
On Sat, Nov 28, 2020 at 04:47:24PM -0600, Serge Hallyn wrote:
> On Sat, Nov 28, 2020 at 10:34:58PM +0100, Christian Brauner wrote:
> > The two helpers inode_permission() and generic_permission() are used by the vfs
> > to perform basic permission checking by verifying that the caller is privileged
> > over an inode. In order to handle idmapped mounts we extend the two helpers with
> > an additional user namespace argument.
> > On idmapped mounts the two helpers will make sure to map the inode according to
> > the mount's user namespace and then peform identical permission checks to
> > inode_permission() and generic_permission(). If the initial user namespace is
> > passed nothing changes so non-idmapped mounts will see identical behavior as
> > before.
> >
> > Cc: Christoph Hellwig <hch@lst.de>
> > Cc: David Howells <dhowells@redhat.com>
> > Cc: Al Viro <viro@zeniv.linux.org.uk>
> > Cc: linux-fsdevel@vger.kernel.org
> > Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
>
> Acked-by: Serge Hallyn <serge@hallyn.com>
>
> But request for some comment clarification below.
Thanks!
I've worked in your sugesstions and added proper documentation for all
changed permission checking helpers.
Christian
>
> > ---
> > /* v2 */
> > - Christoph Hellwig <hch@lst.de>:
> > - Don't pollute the vfs with additional helpers simply extend the existing
> > helpers with an additional argument and switch all callers.
> >
> > /* v3 */
> > unchanged
> > ---
> > fs/attr.c | 3 +-
> > fs/btrfs/inode.c | 2 +-
> > fs/btrfs/ioctl.c | 10 ++---
> > fs/ceph/inode.c | 2 +-
> > fs/cifs/cifsfs.c | 2 +-
> > fs/configfs/symlink.c | 2 +-
> > fs/ecryptfs/inode.c | 2 +-
> > fs/exec.c | 2 +-
> > fs/fuse/dir.c | 4 +-
> > fs/gfs2/inode.c | 2 +-
> > fs/hostfs/hostfs_kern.c | 2 +-
> > fs/init.c | 9 ++--
> > fs/kernfs/inode.c | 2 +-
> > fs/libfs.c | 7 ++-
> > fs/namei.c | 68 +++++++++++++++++-------------
> > fs/nfs/dir.c | 2 +-
> > fs/nfsd/nfsfh.c | 2 +-
> > fs/nfsd/vfs.c | 4 +-
> > fs/nilfs2/inode.c | 2 +-
> > fs/notify/fanotify/fanotify_user.c | 2 +-
> > fs/notify/inotify/inotify_user.c | 2 +-
> > fs/ocfs2/file.c | 2 +-
> > fs/ocfs2/refcounttree.c | 4 +-
> > fs/open.c | 10 ++---
> > fs/orangefs/inode.c | 2 +-
> > fs/overlayfs/file.c | 2 +-
> > fs/overlayfs/inode.c | 4 +-
> > fs/overlayfs/util.c | 2 +-
> > fs/posix_acl.c | 17 +++++---
> > fs/proc/base.c | 4 +-
> > fs/proc/fd.c | 2 +-
> > fs/reiserfs/xattr.c | 2 +-
> > fs/remap_range.c | 2 +-
> > fs/udf/file.c | 2 +-
> > fs/verity/enable.c | 2 +-
> > fs/xattr.c | 2 +-
> > include/linux/fs.h | 4 +-
> > include/linux/posix_acl.h | 4 +-
> > ipc/mqueue.c | 2 +-
> > kernel/bpf/inode.c | 4 +-
> > kernel/cgroup/cgroup.c | 2 +-
> > kernel/sys.c | 2 +-
> > mm/madvise.c | 2 +-
> > mm/memcontrol.c | 2 +-
> > mm/mincore.c | 2 +-
> > net/unix/af_unix.c | 2 +-
> > 46 files changed, 122 insertions(+), 96 deletions(-)
> >
> > diff --git a/fs/attr.c b/fs/attr.c
> > index d270f640a192..c9e29e589cec 100644
> > --- a/fs/attr.c
> > +++ b/fs/attr.c
> > @@ -244,7 +244,8 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
> > return -EPERM;
> >
> > if (!inode_owner_or_capable(inode)) {
> > - error = inode_permission(inode, MAY_WRITE);
> > + error = inode_permission(&init_user_ns, inode,
> > + MAY_WRITE);
> > if (error)
> > return error;
> > }
> > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
> > index da58c58ef9aa..32e3bf88d4f7 100644
> > --- a/fs/btrfs/inode.c
> > +++ b/fs/btrfs/inode.c
> > @@ -9794,7 +9794,7 @@ static int btrfs_permission(struct inode *inode, int mask)
> > if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
> > return -EACCES;
> > }
> > - return generic_permission(inode, mask);
> > + return generic_permission(&init_user_ns, inode, mask);
> > }
> >
> > static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
> > diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
> > index 69a384145dc6..74500c15bdc1 100644
> > --- a/fs/btrfs/ioctl.c
> > +++ b/fs/btrfs/ioctl.c
> > @@ -910,7 +910,7 @@ static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
> > BUG_ON(d_inode(victim->d_parent) != dir);
> > audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
> >
> > - error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
> > + error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> > if (error)
> > return error;
> > if (IS_APPEND(dir))
> > @@ -939,7 +939,7 @@ static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
> > return -EEXIST;
> > if (IS_DEADDIR(dir))
> > return -ENOENT;
> > - return inode_permission(dir, MAY_WRITE | MAY_EXEC);
> > + return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> > }
> >
> > /*
> > @@ -2487,7 +2487,7 @@ static int btrfs_search_path_in_tree_user(struct inode *inode,
> > ret = PTR_ERR(temp_inode);
> > goto out_put;
> > }
> > - ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC);
> > + ret = inode_permission(&init_user_ns, temp_inode, MAY_READ | MAY_EXEC);
> > iput(temp_inode);
> > if (ret) {
> > ret = -EACCES;
> > @@ -3017,7 +3017,7 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
> > if (root == dest)
> > goto out_dput;
> >
> > - err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
> > + err = inode_permission(&init_user_ns, inode, MAY_WRITE | MAY_EXEC);
> > if (err)
> > goto out_dput;
> > }
> > @@ -3088,7 +3088,7 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
> > * running and allows defrag on files open in read-only mode.
> > */
> > if (!capable(CAP_SYS_ADMIN) &&
> > - inode_permission(inode, MAY_WRITE)) {
> > + inode_permission(&init_user_ns, inode, MAY_WRITE)) {
> > ret = -EPERM;
> > goto out;
> > }
> > diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
> > index 526faf4778ce..abfe42df8a1a 100644
> > --- a/fs/ceph/inode.c
> > +++ b/fs/ceph/inode.c
> > @@ -2335,7 +2335,7 @@ int ceph_permission(struct inode *inode, int mask)
> > err = ceph_do_getattr(inode, CEPH_CAP_AUTH_SHARED, false);
> >
> > if (!err)
> > - err = generic_permission(inode, mask);
> > + err = generic_permission(&init_user_ns, inode, mask);
> > return err;
> > }
> >
> > diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
> > index 472cb7777e3e..f79dbc581eee 100644
> > --- a/fs/cifs/cifsfs.c
> > +++ b/fs/cifs/cifsfs.c
> > @@ -316,7 +316,7 @@ static int cifs_permission(struct inode *inode, int mask)
> > on the client (above and beyond ACL on servers) for
> > servers which do not support setting and viewing mode bits,
> > so allowing client to check permissions is useful */
> > - return generic_permission(inode, mask);
> > + return generic_permission(&init_user_ns, inode, mask);
> > }
> >
> > static struct kmem_cache *cifs_inode_cachep;
> > diff --git a/fs/configfs/symlink.c b/fs/configfs/symlink.c
> > index cb61467478ca..0b592c55f38e 100644
> > --- a/fs/configfs/symlink.c
> > +++ b/fs/configfs/symlink.c
> > @@ -197,7 +197,7 @@ int configfs_symlink(struct inode *dir, struct dentry *dentry, const char *symna
> > if (dentry->d_inode || d_unhashed(dentry))
> > ret = -EEXIST;
> > else
> > - ret = inode_permission(dir, MAY_WRITE | MAY_EXEC);
> > + ret = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> > if (!ret)
> > ret = type->ct_item_ops->allow_link(parent_item, target_item);
> > if (!ret) {
> > diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
> > index e23752d9a79f..9b1ae410983c 100644
> > --- a/fs/ecryptfs/inode.c
> > +++ b/fs/ecryptfs/inode.c
> > @@ -864,7 +864,7 @@ int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
> > static int
> > ecryptfs_permission(struct inode *inode, int mask)
> > {
> > - return inode_permission(ecryptfs_inode_to_lower(inode), mask);
> > + return inode_permission(&init_user_ns, ecryptfs_inode_to_lower(inode), mask);
> > }
> >
> > /**
> > diff --git a/fs/exec.c b/fs/exec.c
> > index 8e75d7a33514..b499a1a03934 100644
> > --- a/fs/exec.c
> > +++ b/fs/exec.c
> > @@ -1391,7 +1391,7 @@ EXPORT_SYMBOL(begin_new_exec);
> > void would_dump(struct linux_binprm *bprm, struct file *file)
> > {
> > struct inode *inode = file_inode(file);
> > - if (inode_permission(inode, MAY_READ) < 0) {
> > + if (inode_permission(&init_user_ns, inode, MAY_READ) < 0) {
> > struct user_namespace *old, *user_ns;
> > bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
> >
> > diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
> > index ff7dbeb16f88..7ce7baed3f4f 100644
> > --- a/fs/fuse/dir.c
> > +++ b/fs/fuse/dir.c
> > @@ -1254,7 +1254,7 @@ static int fuse_permission(struct inode *inode, int mask)
> > }
> >
> > if (fc->default_permissions) {
> > - err = generic_permission(inode, mask);
> > + err = generic_permission(&init_user_ns, inode, mask);
> >
> > /* If permission is denied, try to refresh file
> > attributes. This is also needed, because the root
> > @@ -1262,7 +1262,7 @@ static int fuse_permission(struct inode *inode, int mask)
> > if (err == -EACCES && !refreshed) {
> > err = fuse_perm_getattr(inode, mask);
> > if (!err)
> > - err = generic_permission(inode, mask);
> > + err = generic_permission(&init_user_ns, inode, mask);
> > }
> >
> > /* Note: the opposite of the above test does not
> > diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
> > index 077ccb1b3ccc..8445588b58a6 100644
> > --- a/fs/gfs2/inode.c
> > +++ b/fs/gfs2/inode.c
> > @@ -1851,7 +1851,7 @@ int gfs2_permission(struct inode *inode, int mask)
> > if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
> > error = -EPERM;
> > else
> > - error = generic_permission(inode, mask);
> > + error = generic_permission(&init_user_ns, inode, mask);
> > if (gfs2_holder_initialized(&i_gh))
> > gfs2_glock_dq_uninit(&i_gh);
> >
> > diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
> > index c070c0d8e3e9..36da0c31d053 100644
> > --- a/fs/hostfs/hostfs_kern.c
> > +++ b/fs/hostfs/hostfs_kern.c
> > @@ -779,7 +779,7 @@ static int hostfs_permission(struct inode *ino, int desired)
> > err = access_file(name, r, w, x);
> > __putname(name);
> > if (!err)
> > - err = generic_permission(ino, desired);
> > + err = generic_permission(&init_user_ns, ino, desired);
> > return err;
> > }
> >
> > diff --git a/fs/init.c b/fs/init.c
> > index e9c320a48cf1..2b4842f4802b 100644
> > --- a/fs/init.c
> > +++ b/fs/init.c
> > @@ -49,7 +49,8 @@ int __init init_chdir(const char *filename)
> > error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
> > if (error)
> > return error;
> > - error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> > + error = inode_permission(&init_user_ns, path.dentry->d_inode,
> > + MAY_EXEC | MAY_CHDIR);
> > if (!error)
> > set_fs_pwd(current->fs, &path);
> > path_put(&path);
> > @@ -64,7 +65,8 @@ int __init init_chroot(const char *filename)
> > error = kern_path(filename, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path);
> > if (error)
> > return error;
> > - error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> > + error = inode_permission(&init_user_ns, path.dentry->d_inode,
> > + MAY_EXEC | MAY_CHDIR);
> > if (error)
> > goto dput_and_out;
> > error = -EPERM;
> > @@ -118,7 +120,8 @@ int __init init_eaccess(const char *filename)
> > error = kern_path(filename, LOOKUP_FOLLOW, &path);
> > if (error)
> > return error;
> > - error = inode_permission(d_inode(path.dentry), MAY_ACCESS);
> > + error = inode_permission(&init_user_ns, d_inode(path.dentry),
> > + MAY_ACCESS);
> > path_put(&path);
> > return error;
> > }
> > diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
> > index fc2469a20fed..ff5598cc1de0 100644
> > --- a/fs/kernfs/inode.c
> > +++ b/fs/kernfs/inode.c
> > @@ -285,7 +285,7 @@ int kernfs_iop_permission(struct inode *inode, int mask)
> > kernfs_refresh_inode(kn, inode);
> > mutex_unlock(&kernfs_mutex);
> >
> > - return generic_permission(inode, mask);
> > + return generic_permission(&init_user_ns, inode, mask);
> > }
> >
> > int kernfs_xattr_get(struct kernfs_node *kn, const char *name,
> > diff --git a/fs/libfs.c b/fs/libfs.c
> > index fc34361c1489..23d0a00668fd 100644
> > --- a/fs/libfs.c
> > +++ b/fs/libfs.c
> > @@ -1316,9 +1316,14 @@ static ssize_t empty_dir_listxattr(struct dentry *dentry, char *list, size_t siz
> > return -EOPNOTSUPP;
> > }
> >
> > +static int empty_dir_permission(struct inode *inode, int mask)
> > +{
> > + return generic_permission(&init_user_ns, inode, mask);
> > +}
> > +
> > static const struct inode_operations empty_dir_inode_operations = {
> > .lookup = empty_dir_lookup,
> > - .permission = generic_permission,
> > + .permission = empty_dir_permission,
> > .setattr = empty_dir_setattr,
> > .getattr = empty_dir_getattr,
> > .listxattr = empty_dir_listxattr,
> > diff --git a/fs/namei.c b/fs/namei.c
> > index 3f52730af6c5..38222f92efb6 100644
> > --- a/fs/namei.c
> > +++ b/fs/namei.c
> > @@ -259,7 +259,7 @@ void putname(struct filename *name)
> > __putname(name);
> > }
> >
> > -static int check_acl(struct inode *inode, int mask)
> > +static int check_acl(struct user_namespace *user_ns, struct inode *inode, int mask)
> > {
> > #ifdef CONFIG_FS_POSIX_ACL
> > struct posix_acl *acl;
> > @@ -271,14 +271,14 @@ static int check_acl(struct inode *inode, int mask)
> > /* no ->get_acl() calls in RCU mode... */
> > if (is_uncached_acl(acl))
> > return -ECHILD;
> > - return posix_acl_permission(inode, acl, mask);
> > + return posix_acl_permission(user_ns, inode, acl, mask);
> > }
> >
> > acl = get_acl(inode, ACL_TYPE_ACCESS);
> > if (IS_ERR(acl))
> > return PTR_ERR(acl);
> > if (acl) {
> > - int error = posix_acl_permission(inode, acl, mask);
> > + int error = posix_acl_permission(user_ns, inode, acl, mask);
> > posix_acl_release(acl);
> > return error;
> > }
> > @@ -293,12 +293,15 @@ static int check_acl(struct inode *inode, int mask)
> > * Note that the POSIX ACL check cares about the MAY_NOT_BLOCK bit,
> > * for RCU walking.
> > */
> > -static int acl_permission_check(struct inode *inode, int mask)
> > +static int acl_permission_check(struct user_namespace *user_ns,
> > + struct inode *inode, int mask)
> > {
> > unsigned int mode = inode->i_mode;
> > + kuid_t i_uid;
> >
> > /* Are we the owner? If so, ACL's don't matter */
> > - if (likely(uid_eq(current_fsuid(), inode->i_uid))) {
> > + i_uid = i_uid_into_mnt(user_ns, inode);
> > + if (likely(uid_eq(current_fsuid(), i_uid))) {
> > mask &= 7;
> > mode >>= 6;
> > return (mask & ~mode) ? -EACCES : 0;
> > @@ -306,7 +309,7 @@ static int acl_permission_check(struct inode *inode, int mask)
> >
> > /* Do we have ACL's? */
> > if (IS_POSIXACL(inode) && (mode & S_IRWXG)) {
> > - int error = check_acl(inode, mask);
> > + int error = check_acl(user_ns, inode, mask);
> > if (error != -EAGAIN)
> > return error;
> > }
> > @@ -320,7 +323,8 @@ static int acl_permission_check(struct inode *inode, int mask)
> > * about? Need to check group ownership if so.
> > */
> > if (mask & (mode ^ (mode >> 3))) {
> > - if (in_group_p(inode->i_gid))
> > + kgid_t kgid = i_gid_into_mnt(user_ns, inode);
> > + if (in_group_p(kgid))
> > mode >>= 3;
> > }
> >
> > @@ -343,25 +347,25 @@ static int acl_permission_check(struct inode *inode, int mask)
> > * request cannot be satisfied (eg. requires blocking or too much complexity).
>
> The fn header needs a very clear update
Added.
>
> > * It would then be called again in ref-walk mode.
> > */
> > -int generic_permission(struct inode *inode, int mask)
> > +int generic_permission(struct user_namespace *user_ns, struct inode *inode,
> > + int mask)
> > {
> > int ret;
> >
> > /*
> > * Do the basic permission checks.
> > */
> > - ret = acl_permission_check(inode, mask);
> > + ret = acl_permission_check(user_ns, inode, mask);
> > if (ret != -EACCES)
> > return ret;
> >
> > if (S_ISDIR(inode->i_mode)) {
> > /* DACs are overridable for directories */
> > if (!(mask & MAY_WRITE))
> > - if (capable_wrt_inode_uidgid(&init_user_ns, inode,
> > + if (capable_wrt_inode_uidgid(user_ns, inode,
> > CAP_DAC_READ_SEARCH))
> > return 0;
> > - if (capable_wrt_inode_uidgid(&init_user_ns, inode,
> > - CAP_DAC_OVERRIDE))
> > + if (capable_wrt_inode_uidgid(user_ns, inode, CAP_DAC_OVERRIDE))
> > return 0;
> > return -EACCES;
> > }
> > @@ -371,7 +375,7 @@ int generic_permission(struct inode *inode, int mask)
> > */
> > mask &= MAY_READ | MAY_WRITE | MAY_EXEC;
> > if (mask == MAY_READ)
> > - if (capable_wrt_inode_uidgid(&init_user_ns, inode,
> > + if (capable_wrt_inode_uidgid(user_ns, inode,
> > CAP_DAC_READ_SEARCH))
> > return 0;
> > /*
> > @@ -380,8 +384,7 @@ int generic_permission(struct inode *inode, int mask)
> > * at least one exec bit set.
> > */
> > if (!(mask & MAY_EXEC) || (inode->i_mode & S_IXUGO))
> > - if (capable_wrt_inode_uidgid(&init_user_ns, inode,
> > - CAP_DAC_OVERRIDE))
> > + if (capable_wrt_inode_uidgid(user_ns, inode, CAP_DAC_OVERRIDE))
> > return 0;
> >
> > return -EACCES;
> > @@ -394,7 +397,8 @@ EXPORT_SYMBOL(generic_permission);
> > * flag in inode->i_opflags, that says "this has not special
>
> Ditto.
>
> > * permission function, use the fast case".
> > */
> > -static inline int do_inode_permission(struct inode *inode, int mask)
> > +static inline int do_inode_permission(struct user_namespace *user_ns,
> > + struct inode *inode, int mask)
> > {
> > if (unlikely(!(inode->i_opflags & IOP_FASTPERM))) {
> > if (likely(inode->i_op->permission))
> > @@ -405,7 +409,7 @@ static inline int do_inode_permission(struct inode *inode, int mask)
> > inode->i_opflags |= IOP_FASTPERM;
> > spin_unlock(&inode->i_lock);
> > }
> > - return generic_permission(inode, mask);
> > + return generic_permission(user_ns, inode, mask);
> > }
> >
> > /**
> > @@ -430,6 +434,7 @@ static int sb_permission(struct super_block *sb, struct inode *inode, int mask)
> >
> > /**
> > * inode_permission - Check for access rights to a given inode
> > + * @userns: The user namespace the inode is seen from
>
> This "the inode is seen from" is confusing. Is it the mnt_user_ns through
> which the inode was found, or the userns of the task which sees the inode?
> It must be the former, so how about something like
>
> The user namespace of the mountpoint through which the inode was found
Sounds good! I used your suggestion.
>
> > * @inode: Inode to check permission on
> > * @mask: Right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC)
> > *
> > @@ -439,7 +444,8 @@ static int sb_permission(struct super_block *sb, struct inode *inode, int mask)
> > *
> > * When checking for MAY_APPEND, MAY_WRITE must also be set in @mask.
> > */
> > -int inode_permission(struct inode *inode, int mask)
> > +int inode_permission(struct user_namespace *user_ns,
> > + struct inode *inode, int mask)
> > {
> > int retval;
> >
> > @@ -463,7 +469,7 @@ int inode_permission(struct inode *inode, int mask)
> > return -EACCES;
> > }
> >
> > - retval = do_inode_permission(inode, mask);
> > + retval = do_inode_permission(user_ns, inode, mask);
> > if (retval)
> > return retval;
> >
> > @@ -1009,7 +1015,7 @@ static bool safe_hardlink_source(struct inode *inode)
> > return false;
> >
> > /* Hardlinking to unreadable or unwritable sources is dangerous. */
> > - if (inode_permission(inode, MAY_READ | MAY_WRITE))
> > + if (inode_permission(&init_user_ns, inode, MAY_READ | MAY_WRITE))
> > return false;
> >
> > return true;
> > @@ -1569,13 +1575,14 @@ static struct dentry *lookup_slow(const struct qstr *name,
> > static inline int may_lookup(struct nameidata *nd)
> > {
> > if (nd->flags & LOOKUP_RCU) {
> > - int err = inode_permission(nd->inode, MAY_EXEC|MAY_NOT_BLOCK);
> > + int err = inode_permission(&init_user_ns, nd->inode,
> > + MAY_EXEC | MAY_NOT_BLOCK);
> > if (err != -ECHILD)
> > return err;
> > if (unlazy_walk(nd))
> > return -ECHILD;
> > }
> > - return inode_permission(nd->inode, MAY_EXEC);
> > + return inode_permission(&init_user_ns, nd->inode, MAY_EXEC);
> > }
> >
> > static int reserve_stack(struct nameidata *nd, struct path *link, unsigned seq)
> > @@ -2507,7 +2514,7 @@ static int lookup_one_len_common(const char *name, struct dentry *base,
> > return err;
> > }
> >
> > - return inode_permission(base->d_inode, MAY_EXEC);
> > + return inode_permission(&init_user_ns, base->d_inode, MAY_EXEC);
> > }
> >
> > /**
> > @@ -2701,7 +2708,7 @@ static int may_delete(struct inode *dir, struct dentry *victim, bool isdir)
> >
> > audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
> >
> > - error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
> > + error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> > if (error)
> > return error;
> > if (IS_APPEND(dir))
> > @@ -2745,7 +2752,7 @@ static inline int may_create(struct inode *dir, struct dentry *child)
> > if (!kuid_has_mapping(s_user_ns, current_fsuid()) ||
> > !kgid_has_mapping(s_user_ns, current_fsgid()))
> > return -EOVERFLOW;
> > - return inode_permission(dir, MAY_WRITE | MAY_EXEC);
> > + return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> > }
> >
> > /*
> > @@ -2875,7 +2882,7 @@ static int may_open(const struct path *path, int acc_mode, int flag)
> > break;
> > }
> >
> > - error = inode_permission(inode, MAY_OPEN | acc_mode);
> > + error = inode_permission(&init_user_ns, inode, MAY_OPEN | acc_mode);
> > if (error)
> > return error;
> >
> > @@ -2937,7 +2944,8 @@ static int may_o_create(const struct path *dir, struct dentry *dentry, umode_t m
> > !kgid_has_mapping(s_user_ns, current_fsgid()))
> > return -EOVERFLOW;
> >
> > - error = inode_permission(dir->dentry->d_inode, MAY_WRITE | MAY_EXEC);
> > + error = inode_permission(&init_user_ns, dir->dentry->d_inode,
> > + MAY_WRITE | MAY_EXEC);
> > if (error)
> > return error;
> >
> > @@ -3274,7 +3282,7 @@ struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag)
> > int error;
> >
> > /* we want directory to be writable */
> > - error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
> > + error = inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> > if (error)
> > goto out_err;
> > error = -EOPNOTSUPP;
> > @@ -4265,12 +4273,12 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
> > */
> > if (new_dir != old_dir) {
> > if (is_dir) {
> > - error = inode_permission(source, MAY_WRITE);
> > + error = inode_permission(&init_user_ns, source, MAY_WRITE);
> > if (error)
> > return error;
> > }
> > if ((flags & RENAME_EXCHANGE) && new_is_dir) {
> > - error = inode_permission(target, MAY_WRITE);
> > + error = inode_permission(&init_user_ns, target, MAY_WRITE);
> > if (error)
> > return error;
> > }
> > diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
> > index 4e011adaf967..170ecc575519 100644
> > --- a/fs/nfs/dir.c
> > +++ b/fs/nfs/dir.c
> > @@ -2788,7 +2788,7 @@ int nfs_permission(struct inode *inode, int mask)
> >
> > res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
> > if (res == 0)
> > - res = generic_permission(inode, mask);
> > + res = generic_permission(&init_user_ns, inode, mask);
> > goto out;
> > }
> > EXPORT_SYMBOL_GPL(nfs_permission);
> > diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c
> > index c81dbbad8792..380f0f74740c 100644
> > --- a/fs/nfsd/nfsfh.c
> > +++ b/fs/nfsd/nfsfh.c
> > @@ -40,7 +40,7 @@ static int nfsd_acceptable(void *expv, struct dentry *dentry)
> > /* make sure parents give x permission to user */
> > int err;
> > parent = dget_parent(tdentry);
> > - err = inode_permission(d_inode(parent), MAY_EXEC);
> > + err = inode_permission(&init_user_ns, d_inode(parent), MAY_EXEC);
> > if (err < 0) {
> > dput(parent);
> > break;
> > diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> > index 1ecaceebee13..3cad79c3b441 100644
> > --- a/fs/nfsd/vfs.c
> > +++ b/fs/nfsd/vfs.c
> > @@ -2380,13 +2380,13 @@ nfsd_permission(struct svc_rqst *rqstp, struct svc_export *exp,
> > return 0;
> >
> > /* This assumes NFSD_MAY_{READ,WRITE,EXEC} == MAY_{READ,WRITE,EXEC} */
> > - err = inode_permission(inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC));
> > + err = inode_permission(&init_user_ns, inode, acc & (MAY_READ|MAY_WRITE|MAY_EXEC));
> >
> > /* Allow read access to binaries even when mode 111 */
> > if (err == -EACCES && S_ISREG(inode->i_mode) &&
> > (acc == (NFSD_MAY_READ | NFSD_MAY_OWNER_OVERRIDE) ||
> > acc == (NFSD_MAY_READ | NFSD_MAY_READ_IF_EXEC)))
> > - err = inode_permission(inode, MAY_EXEC);
> > + err = inode_permission(&init_user_ns, inode, MAY_EXEC);
> >
> > return err? nfserrno(err) : 0;
> > }
> > diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
> > index 745d371d6fea..b6517220cad5 100644
> > --- a/fs/nilfs2/inode.c
> > +++ b/fs/nilfs2/inode.c
> > @@ -851,7 +851,7 @@ int nilfs_permission(struct inode *inode, int mask)
> > root->cno != NILFS_CPTREE_CURRENT_CNO)
> > return -EROFS; /* snapshot is not writable */
> >
> > - return generic_permission(inode, mask);
> > + return generic_permission(&init_user_ns, inode, mask);
> > }
> >
> > int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh)
> > diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
> > index 3e01d8f2ab90..de4d01bb1d8d 100644
> > --- a/fs/notify/fanotify/fanotify_user.c
> > +++ b/fs/notify/fanotify/fanotify_user.c
> > @@ -702,7 +702,7 @@ static int fanotify_find_path(int dfd, const char __user *filename,
> > }
> >
> > /* you can only watch an inode if you have read permissions on it */
> > - ret = inode_permission(path->dentry->d_inode, MAY_READ);
> > + ret = inode_permission(&init_user_ns, path->dentry->d_inode, MAY_READ);
> > if (ret) {
> > path_put(path);
> > goto out;
> > diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
> > index 186722ba3894..e995fd4e4e53 100644
> > --- a/fs/notify/inotify/inotify_user.c
> > +++ b/fs/notify/inotify/inotify_user.c
> > @@ -343,7 +343,7 @@ static int inotify_find_inode(const char __user *dirname, struct path *path,
> > if (error)
> > return error;
> > /* you can only watch an inode if you have read permissions on it */
> > - error = inode_permission(path->dentry->d_inode, MAY_READ);
> > + error = inode_permission(&init_user_ns, path->dentry->d_inode, MAY_READ);
> > if (error) {
> > path_put(path);
> > return error;
> > diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
> > index 85979e2214b3..0c75619adf54 100644
> > --- a/fs/ocfs2/file.c
> > +++ b/fs/ocfs2/file.c
> > @@ -1355,7 +1355,7 @@ int ocfs2_permission(struct inode *inode, int mask)
> > dump_stack();
> > }
> >
> > - ret = generic_permission(inode, mask);
> > + ret = generic_permission(&init_user_ns, inode, mask);
> >
> > ocfs2_inode_unlock_tracker(inode, 0, &oh, had_lock);
> > out:
> > diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
> > index 3b397fa9c9e8..c26937824be1 100644
> > --- a/fs/ocfs2/refcounttree.c
> > +++ b/fs/ocfs2/refcounttree.c
> > @@ -4346,7 +4346,7 @@ static inline int ocfs2_may_create(struct inode *dir, struct dentry *child)
> > return -EEXIST;
> > if (IS_DEADDIR(dir))
> > return -ENOENT;
> > - return inode_permission(dir, MAY_WRITE | MAY_EXEC);
> > + return inode_permission(&init_user_ns, dir, MAY_WRITE | MAY_EXEC);
> > }
> >
> > /**
> > @@ -4400,7 +4400,7 @@ static int ocfs2_vfs_reflink(struct dentry *old_dentry, struct inode *dir,
> > * file.
> > */
> > if (!preserve) {
> > - error = inode_permission(inode, MAY_READ);
> > + error = inode_permission(&init_user_ns, inode, MAY_READ);
> > if (error)
> > return error;
> > }
> > diff --git a/fs/open.c b/fs/open.c
> > index 9af548fb841b..b0e8430e29f3 100644
> > --- a/fs/open.c
> > +++ b/fs/open.c
> > @@ -83,7 +83,7 @@ long vfs_truncate(const struct path *path, loff_t length)
> > if (error)
> > goto out;
> >
> > - error = inode_permission(inode, MAY_WRITE);
> > + error = inode_permission(&init_user_ns, inode, MAY_WRITE);
> > if (error)
> > goto mnt_drop_write_and_out;
> >
> > @@ -436,7 +436,7 @@ static long do_faccessat(int dfd, const char __user *filename, int mode, int fla
> > goto out_path_release;
> > }
> >
> > - res = inode_permission(inode, mode | MAY_ACCESS);
> > + res = inode_permission(&init_user_ns, inode, mode | MAY_ACCESS);
> > /* SuS v2 requires we report a read only fs too */
> > if (res || !(mode & S_IWOTH) || special_file(inode->i_mode))
> > goto out_path_release;
> > @@ -492,7 +492,7 @@ SYSCALL_DEFINE1(chdir, const char __user *, filename)
> > if (error)
> > goto out;
> >
> > - error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> > + error = inode_permission(&init_user_ns, path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> > if (error)
> > goto dput_and_out;
> >
> > @@ -521,7 +521,7 @@ SYSCALL_DEFINE1(fchdir, unsigned int, fd)
> > if (!d_can_lookup(f.file->f_path.dentry))
> > goto out_putf;
> >
> > - error = inode_permission(file_inode(f.file), MAY_EXEC | MAY_CHDIR);
> > + error = inode_permission(&init_user_ns, file_inode(f.file), MAY_EXEC | MAY_CHDIR);
> > if (!error)
> > set_fs_pwd(current->fs, &f.file->f_path);
> > out_putf:
> > @@ -540,7 +540,7 @@ SYSCALL_DEFINE1(chroot, const char __user *, filename)
> > if (error)
> > goto out;
> >
> > - error = inode_permission(path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> > + error = inode_permission(&init_user_ns, path.dentry->d_inode, MAY_EXEC | MAY_CHDIR);
> > if (error)
> > goto dput_and_out;
> >
> > diff --git a/fs/orangefs/inode.c b/fs/orangefs/inode.c
> > index 48f0547d4850..4c790cc8042d 100644
> > --- a/fs/orangefs/inode.c
> > +++ b/fs/orangefs/inode.c
> > @@ -933,7 +933,7 @@ int orangefs_permission(struct inode *inode, int mask)
> > if (ret < 0)
> > return ret;
> >
> > - return generic_permission(inode, mask);
> > + return generic_permission(&init_user_ns, inode, mask);
> > }
> >
> > int orangefs_update_time(struct inode *inode, struct timespec64 *time, int flags)
> > diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
> > index efccb7c1f9bc..f966b5108358 100644
> > --- a/fs/overlayfs/file.c
> > +++ b/fs/overlayfs/file.c
> > @@ -50,7 +50,7 @@ static struct file *ovl_open_realfile(const struct file *file,
> > acc_mode |= MAY_APPEND;
> >
> > old_cred = ovl_override_creds(inode->i_sb);
> > - err = inode_permission(realinode, MAY_OPEN | acc_mode);
> > + err = inode_permission(&init_user_ns, realinode, MAY_OPEN | acc_mode);
> > if (err) {
> > realfile = ERR_PTR(err);
> > } else if (!inode_owner_or_capable(realinode)) {
> > diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
> > index b584dca845ba..c8e3c17ca131 100644
> > --- a/fs/overlayfs/inode.c
> > +++ b/fs/overlayfs/inode.c
> > @@ -294,7 +294,7 @@ int ovl_permission(struct inode *inode, int mask)
> > * Check overlay inode with the creds of task and underlying inode
> > * with creds of mounter
> > */
> > - err = generic_permission(inode, mask);
> > + err = generic_permission(&init_user_ns, inode, mask);
> > if (err)
> > return err;
> >
> > @@ -305,7 +305,7 @@ int ovl_permission(struct inode *inode, int mask)
> > /* Make sure mounter can read file for copy up later */
> > mask |= MAY_READ;
> > }
> > - err = inode_permission(realinode, mask);
> > + err = inode_permission(&init_user_ns, realinode, mask);
> > revert_creds(old_cred);
> >
> > return err;
> > diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c
> > index 23f475627d07..ff67da201303 100644
> > --- a/fs/overlayfs/util.c
> > +++ b/fs/overlayfs/util.c
> > @@ -476,7 +476,7 @@ struct file *ovl_path_open(struct path *path, int flags)
> > BUG();
> > }
> >
> > - err = inode_permission(inode, acc_mode | MAY_OPEN);
> > + err = inode_permission(&init_user_ns, inode, acc_mode | MAY_OPEN);
> > if (err)
> > return ERR_PTR(err);
> >
> > diff --git a/fs/posix_acl.c b/fs/posix_acl.c
> > index 4ca6d53c6f0a..5b6296cc89c4 100644
> > --- a/fs/posix_acl.c
> > +++ b/fs/posix_acl.c
> > @@ -345,10 +345,13 @@ EXPORT_SYMBOL(posix_acl_from_mode);
> > * by the acl. Returns -E... otherwise.
> > */
> > int
> > -posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want)
> > +posix_acl_permission(struct user_namespace *user_ns, struct inode *inode,
> > + const struct posix_acl *acl, int want)
> > {
> > const struct posix_acl_entry *pa, *pe, *mask_obj;
> > int found = 0;
> > + kuid_t uid;
> > + kgid_t gid;
> >
> > want &= MAY_READ | MAY_WRITE | MAY_EXEC;
> >
> > @@ -356,22 +359,26 @@ posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want)
> > switch(pa->e_tag) {
> > case ACL_USER_OBJ:
> > /* (May have been checked already) */
> > - if (uid_eq(inode->i_uid, current_fsuid()))
> > + uid = i_uid_into_mnt(user_ns, inode);
> > + if (uid_eq(uid, current_fsuid()))
> > goto check_perm;
> > break;
> > case ACL_USER:
> > - if (uid_eq(pa->e_uid, current_fsuid()))
> > + uid = kuid_into_mnt(user_ns, pa->e_uid);
> > + if (uid_eq(uid, current_fsuid()))
> > goto mask;
> > break;
> > case ACL_GROUP_OBJ:
> > - if (in_group_p(inode->i_gid)) {
> > + gid = i_gid_into_mnt(user_ns, inode);
> > + if (in_group_p(gid)) {
> > found = 1;
> > if ((pa->e_perm & want) == want)
> > goto mask;
> > }
> > break;
> > case ACL_GROUP:
> > - if (in_group_p(pa->e_gid)) {
> > + gid = kgid_into_mnt(user_ns, pa->e_gid);
> > + if (in_group_p(gid)) {
> > found = 1;
> > if ((pa->e_perm & want) == want)
> > goto mask;
> > diff --git a/fs/proc/base.c b/fs/proc/base.c
> > index b362523a9829..ff7259f820c8 100644
> > --- a/fs/proc/base.c
> > +++ b/fs/proc/base.c
> > @@ -751,7 +751,7 @@ static int proc_pid_permission(struct inode *inode, int mask)
> >
> > return -EPERM;
> > }
> > - return generic_permission(inode, mask);
> > + return generic_permission(&init_user_ns, inode, mask);
> > }
> >
> >
> > @@ -3489,7 +3489,7 @@ static int proc_tid_comm_permission(struct inode *inode, int mask)
> > return 0;
> > }
> >
> > - return generic_permission(inode, mask);
> > + return generic_permission(&init_user_ns, inode, mask);
> > }
> >
> > static const struct inode_operations proc_tid_comm_inode_operations = {
> > diff --git a/fs/proc/fd.c b/fs/proc/fd.c
> > index 81882a13212d..ad692a39381d 100644
> > --- a/fs/proc/fd.c
> > +++ b/fs/proc/fd.c
> > @@ -299,7 +299,7 @@ int proc_fd_permission(struct inode *inode, int mask)
> > struct task_struct *p;
> > int rv;
> >
> > - rv = generic_permission(inode, mask);
> > + rv = generic_permission(&init_user_ns, inode, mask);
> > if (rv == 0)
> > return rv;
> >
> > diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c
> > index fe63a7c3e0da..ec440d1957a1 100644
> > --- a/fs/reiserfs/xattr.c
> > +++ b/fs/reiserfs/xattr.c
> > @@ -957,7 +957,7 @@ int reiserfs_permission(struct inode *inode, int mask)
> > if (IS_PRIVATE(inode))
> > return 0;
> >
> > - return generic_permission(inode, mask);
> > + return generic_permission(&init_user_ns, inode, mask);
> > }
> >
> > static int xattr_hide_revalidate(struct dentry *dentry, unsigned int flags)
> > diff --git a/fs/remap_range.c b/fs/remap_range.c
> > index e6099beefa97..9e5b27641756 100644
> > --- a/fs/remap_range.c
> > +++ b/fs/remap_range.c
> > @@ -438,7 +438,7 @@ static bool allow_file_dedupe(struct file *file)
> > return true;
> > if (uid_eq(current_fsuid(), file_inode(file)->i_uid))
> > return true;
> > - if (!inode_permission(file_inode(file), MAY_WRITE))
> > + if (!inode_permission(&init_user_ns, file_inode(file), MAY_WRITE))
> > return true;
> > return false;
> > }
> > diff --git a/fs/udf/file.c b/fs/udf/file.c
> > index ad8eefad27d7..928283925d68 100644
> > --- a/fs/udf/file.c
> > +++ b/fs/udf/file.c
> > @@ -183,7 +183,7 @@ long udf_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> > long old_block, new_block;
> > int result;
> >
> > - if (inode_permission(inode, MAY_READ) != 0) {
> > + if (inode_permission(&init_user_ns, inode, MAY_READ) != 0) {
> > udf_debug("no permission to access inode %lu\n", inode->i_ino);
> > return -EPERM;
> > }
> > diff --git a/fs/verity/enable.c b/fs/verity/enable.c
> > index 5ab3bbec8108..7449ef0050f4 100644
> > --- a/fs/verity/enable.c
> > +++ b/fs/verity/enable.c
> > @@ -369,7 +369,7 @@ int fsverity_ioctl_enable(struct file *filp, const void __user *uarg)
> > * has verity enabled, and to stabilize the data being hashed.
> > */
> >
> > - err = inode_permission(inode, MAY_WRITE);
> > + err = inode_permission(&init_user_ns, inode, MAY_WRITE);
> > if (err)
> > return err;
> >
> > diff --git a/fs/xattr.c b/fs/xattr.c
> > index cd7a563e8bcd..61a9947f62f4 100644
> > --- a/fs/xattr.c
> > +++ b/fs/xattr.c
> > @@ -131,7 +131,7 @@ xattr_permission(struct inode *inode, const char *name, int mask)
> > return -EPERM;
> > }
> >
> > - return inode_permission(inode, mask);
> > + return inode_permission(&init_user_ns, inode, mask);
> > }
> >
> > /*
> > diff --git a/include/linux/fs.h b/include/linux/fs.h
> > index 004686f49e32..fa1137a232d1 100644
> > --- a/include/linux/fs.h
> > +++ b/include/linux/fs.h
> > @@ -2803,8 +2803,8 @@ static inline int bmap(struct inode *inode, sector_t *block)
> > #endif
> >
> > extern int notify_change(struct dentry *, struct iattr *, struct inode **);
> > -extern int inode_permission(struct inode *, int);
> > -extern int generic_permission(struct inode *, int);
> > +extern int inode_permission(struct user_namespace *, struct inode *, int);
> > +extern int generic_permission(struct user_namespace *, struct inode *, int);
> > extern int __check_sticky(struct inode *dir, struct inode *inode);
> >
> > static inline bool execute_ok(struct inode *inode)
> > diff --git a/include/linux/posix_acl.h b/include/linux/posix_acl.h
> > index 90797f1b421d..8276baefed13 100644
> > --- a/include/linux/posix_acl.h
> > +++ b/include/linux/posix_acl.h
> > @@ -15,6 +15,8 @@
> > #include <linux/refcount.h>
> > #include <uapi/linux/posix_acl.h>
> >
> > +struct user_namespace;
> > +
> > struct posix_acl_entry {
> > short e_tag;
> > unsigned short e_perm;
> > @@ -62,7 +64,7 @@ posix_acl_release(struct posix_acl *acl)
> > extern void posix_acl_init(struct posix_acl *, int);
> > extern struct posix_acl *posix_acl_alloc(int, gfp_t);
> > extern int posix_acl_valid(struct user_namespace *, const struct posix_acl *);
> > -extern int posix_acl_permission(struct inode *, const struct posix_acl *, int);
> > +extern int posix_acl_permission(struct user_namespace *, struct inode *, const struct posix_acl *, int);
> > extern struct posix_acl *posix_acl_from_mode(umode_t, gfp_t);
> > extern int posix_acl_equiv_mode(const struct posix_acl *, umode_t *);
> > extern int __posix_acl_create(struct posix_acl **, gfp_t, umode_t *);
> > diff --git a/ipc/mqueue.c b/ipc/mqueue.c
> > index beff0cfcd1e8..693f01fe1216 100644
> > --- a/ipc/mqueue.c
> > +++ b/ipc/mqueue.c
> > @@ -873,7 +873,7 @@ static int prepare_open(struct dentry *dentry, int oflag, int ro,
> > if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY))
> > return -EINVAL;
> > acc = oflag2acc[oflag & O_ACCMODE];
> > - return inode_permission(d_inode(dentry), acc);
> > + return inode_permission(&init_user_ns, d_inode(dentry), acc);
> > }
> >
> > static int do_mq_open(const char __user *u_name, int oflag, umode_t mode,
> > diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
> > index dd4b7fd60ee7..f1c393e5d47d 100644
> > --- a/kernel/bpf/inode.c
> > +++ b/kernel/bpf/inode.c
> > @@ -507,7 +507,7 @@ static void *bpf_obj_do_get(const char __user *pathname,
> > return ERR_PTR(ret);
> >
> > inode = d_backing_inode(path.dentry);
> > - ret = inode_permission(inode, ACC_MODE(flags));
> > + ret = inode_permission(&init_user_ns, inode, ACC_MODE(flags));
> > if (ret)
> > goto out;
> >
> > @@ -558,7 +558,7 @@ int bpf_obj_get_user(const char __user *pathname, int flags)
> > static struct bpf_prog *__get_prog_inode(struct inode *inode, enum bpf_prog_type type)
> > {
> > struct bpf_prog *prog;
> > - int ret = inode_permission(inode, MAY_READ);
> > + int ret = inode_permission(&init_user_ns, inode, MAY_READ);
> > if (ret)
> > return ERR_PTR(ret);
> >
> > diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
> > index e41c21819ba0..b13aab5a9715 100644
> > --- a/kernel/cgroup/cgroup.c
> > +++ b/kernel/cgroup/cgroup.c
> > @@ -4673,7 +4673,7 @@ static int cgroup_may_write(const struct cgroup *cgrp, struct super_block *sb)
> > if (!inode)
> > return -ENOMEM;
> >
> > - ret = inode_permission(inode, MAY_WRITE);
> > + ret = inode_permission(&init_user_ns, inode, MAY_WRITE);
> > iput(inode);
> > return ret;
> > }
> > diff --git a/kernel/sys.c b/kernel/sys.c
> > index a730c03ee607..469a659c8e84 100644
> > --- a/kernel/sys.c
> > +++ b/kernel/sys.c
> > @@ -1847,7 +1847,7 @@ static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd)
> > if (!S_ISREG(inode->i_mode) || path_noexec(&exe.file->f_path))
> > goto exit;
> >
> > - err = inode_permission(inode, MAY_EXEC);
> > + err = inode_permission(&init_user_ns, inode, MAY_EXEC);
> > if (err)
> > goto exit;
> >
> > diff --git a/mm/madvise.c b/mm/madvise.c
> > index 416a56b8e757..8afabc363b6b 100644
> > --- a/mm/madvise.c
> > +++ b/mm/madvise.c
> > @@ -540,7 +540,7 @@ static inline bool can_do_pageout(struct vm_area_struct *vma)
> > * opens a side channel.
> > */
> > return inode_owner_or_capable(file_inode(vma->vm_file)) ||
> > - inode_permission(file_inode(vma->vm_file), MAY_WRITE) == 0;
> > + inode_permission(&init_user_ns, file_inode(vma->vm_file), MAY_WRITE) == 0;
> > }
> >
> > static long madvise_pageout(struct vm_area_struct *vma,
> > diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> > index 3dcbf24d2227..aed83b3ad11c 100644
> > --- a/mm/memcontrol.c
> > +++ b/mm/memcontrol.c
> > @@ -4906,7 +4906,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
> >
> > /* the process need read permission on control file */
> > /* AV: shouldn't we check that it's been opened for read instead? */
> > - ret = inode_permission(file_inode(cfile.file), MAY_READ);
> > + ret = inode_permission(&init_user_ns, file_inode(cfile.file), MAY_READ);
> > if (ret < 0)
> > goto out_put_cfile;
> >
> > diff --git a/mm/mincore.c b/mm/mincore.c
> > index 02db1a834021..d5a58e61eac6 100644
> > --- a/mm/mincore.c
> > +++ b/mm/mincore.c
> > @@ -167,7 +167,7 @@ static inline bool can_do_mincore(struct vm_area_struct *vma)
> > * mappings, which opens a side channel.
> > */
> > return inode_owner_or_capable(file_inode(vma->vm_file)) ||
> > - inode_permission(file_inode(vma->vm_file), MAY_WRITE) == 0;
> > + inode_permission(&init_user_ns, file_inode(vma->vm_file), MAY_WRITE) == 0;
> > }
> >
> > static const struct mm_walk_ops mincore_walk_ops = {
> > diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
> > index 41c3303c3357..f568526d4a02 100644
> > --- a/net/unix/af_unix.c
> > +++ b/net/unix/af_unix.c
> > @@ -936,7 +936,7 @@ static struct sock *unix_find_other(struct net *net,
> > if (err)
> > goto fail;
> > inode = d_backing_inode(path.dentry);
> > - err = inode_permission(inode, MAY_WRITE);
> > + err = inode_permission(&init_user_ns, inode, MAY_WRITE);
> > if (err)
> > goto put_fail;
> >
> > --
> > 2.29.2
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 09/38] namei: add idmapped mount aware permission helpers
2020-12-01 10:51 ` Christoph Hellwig
@ 2020-12-01 10:58 ` Christian Brauner
0 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-01 10:58 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Tue, Dec 01, 2020 at 11:51:22AM +0100, Christoph Hellwig wrote:
> The subject is wrong now that there are no new helpers, just new
> arguments.
Thanks for spotting this, adjusting this now!
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 33/38] ext4: support idmapped mounts
2020-12-01 10:54 ` Christoph Hellwig
@ 2020-12-01 11:02 ` Christian Brauner
2020-12-01 11:13 ` Christoph Hellwig
0 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-12-01 11:02 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Tue, Dec 01, 2020 at 11:54:45AM +0100, Christoph Hellwig wrote:
> What is the reason for the config option? The only thing that it
> controls is setting of a single flag.
I wanted to be conservative and give users the option to disable this on
their kernel. Would you prefer if I drop it?
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 33/38] ext4: support idmapped mounts
2020-12-01 11:02 ` Christian Brauner
@ 2020-12-01 11:13 ` Christoph Hellwig
2020-12-01 11:14 ` Christian Brauner
0 siblings, 1 reply; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-01 11:13 UTC (permalink / raw)
To: Christian Brauner
Cc: Christoph Hellwig, Alexander Viro, Christoph Hellwig,
linux-fsdevel, John Johansen, James Morris, Mimi Zohar,
Dmitry Kasatkin, Stephen Smalley, Casey Schaufler, Arnd Bergmann,
Andreas Dilger, OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel,
Josh Triplett, Andy Lutomirski, Theodore Tso, Alban Crequy,
Tycho Andersen, David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux
On Tue, Dec 01, 2020 at 12:02:19PM +0100, Christian Brauner wrote:
> On Tue, Dec 01, 2020 at 11:54:45AM +0100, Christoph Hellwig wrote:
> > What is the reason for the config option? The only thing that it
> > controls is setting of a single flag.
>
> I wanted to be conservative and give users the option to disable this on
> their kernel. Would you prefer if I drop it?
I don't think adding an option per file system scales in any way. If
there is some strong urge to disable the functionality (which I see no
reason for) we could add something like a global sysctl for all on-disk
file systems.
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 33/38] ext4: support idmapped mounts
2020-12-01 11:13 ` Christoph Hellwig
@ 2020-12-01 11:14 ` Christian Brauner
0 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-01 11:14 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Tue, Dec 01, 2020 at 12:13:20PM +0100, Christoph Hellwig wrote:
> On Tue, Dec 01, 2020 at 12:02:19PM +0100, Christian Brauner wrote:
> > On Tue, Dec 01, 2020 at 11:54:45AM +0100, Christoph Hellwig wrote:
> > > What is the reason for the config option? The only thing that it
> > > controls is setting of a single flag.
> >
> > I wanted to be conservative and give users the option to disable this on
> > their kernel. Would you prefer if I drop it?
>
> I don't think adding an option per file system scales in any way. If
> there is some strong urge to disable the functionality (which I see no
> reason for) we could add something like a global sysctl for all on-disk
> file systems.
Sounds reasonable. I'm dropping the config options.
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 07/38] mount: attach mappings to mounts
2020-12-01 10:50 ` Christoph Hellwig
@ 2020-12-01 13:25 ` Tycho Andersen
2020-12-02 9:24 ` Christian Brauner
1 sibling, 0 replies; 73+ messages in thread
From: Tycho Andersen @ 2020-12-01 13:25 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Christian Brauner, Lennart Poettering, Mimi Zohar, David Howells,
Andreas Dilger, containers, Paul Moore, Jonathan Corbet,
smbarber, Christoph Hellwig, Alban Crequy, linux-ext4,
Mrunal Patel, Kees Cook, Arnd Bergmann, selinux, Josh Triplett,
Seth Forshee, Aleksa Sarai, Alexander Viro, Andy Lutomirski,
OGAWA Hirofumi, Geoffrey Thomas, James Bottomley, John Johansen,
Theodore Tso, Dmitry Kasatkin, Stephen Smalley, fstests,
linux-security-module, Eric W. Biederman, linux-api,
Casey Schaufler, linux-fsdevel, linux-integrity, Todd Kjos
On Tue, Dec 01, 2020 at 11:50:25AM +0100, Christoph Hellwig wrote:
> The READ_ONCE still looks suspect as it generally needs to be paired
> with a WRITE_ONCE. The rest looks sane to me.
Yeah, the comment from the other location is,
/* Pairs with smp_load_acquire() in mnt_user_ns(). */
So I think it's just a typo that needs to be fixed.
Tycho
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 01/38] namespace: take lock_mount_hash() directly when changing flags
2020-12-01 10:31 ` Christoph Hellwig
@ 2020-12-02 9:09 ` Christian Brauner
0 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-02 9:09 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Tue, Dec 01, 2020 at 11:31:19AM +0100, Christoph Hellwig wrote:
> Looks good,
>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
Thanks!
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 02/38] mount: make {lock,unlock}_mount_hash() static
2020-12-01 10:32 ` Christoph Hellwig
@ 2020-12-02 9:11 ` Christian Brauner
0 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-02 9:11 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Tue, Dec 01, 2020 at 11:32:03AM +0100, Christoph Hellwig wrote:
> On Sat, Nov 28, 2020 at 10:34:51PM +0100, Christian Brauner wrote:
> > The lock_mount_hash() and unlock_mount_hash() helpers are never called outside a
> > single file. Remove them from the header and make them static to reflect this
> > fact. There's no need to have them callable from other places right now, as
> > Christoph observed.
>
> You are spilling over the usual 73 chars for commit logs, so please check
> this and the other patches.
I've changed all commit messages to adhere to a 73 character limit.
>
> Otherwise looks good:
>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
Thanks!
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 03/38] namespace: only take read lock in do_reconfigure_mnt()
2020-12-01 10:32 ` Christoph Hellwig
@ 2020-12-02 9:14 ` Christian Brauner
0 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-02 9:14 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Tue, Dec 01, 2020 at 11:32:24AM +0100, Christoph Hellwig wrote:
> Looks good,
>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
Thanks!
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 06/38] fs: add id translation helpers
2020-12-01 10:49 ` Christoph Hellwig
@ 2020-12-02 9:16 ` Christian Brauner
0 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-02 9:16 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Tue, Dec 01, 2020 at 11:49:27AM +0100, Christoph Hellwig wrote:
> Looks good,
>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
I've adapted variable naming in this patch. Instead of referring to the
target ns as "to" I'm referring to it as "mnt_userns" as Serge
requested. There are no semantical changes so I've kept your Reviewed-by
on this patch.
Thanks!
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 10/38] inode: add idmapped mount aware init and permission helpers
2020-12-01 10:51 ` Christoph Hellwig
@ 2020-12-02 9:17 ` Christian Brauner
0 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-02 9:17 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Tue, Dec 01, 2020 at 11:51:46AM +0100, Christoph Hellwig wrote:
> Same issue with the subject as for the previous patch.
All commit messages should now have been fixed. I've gone through all of
them once more yesterday.
Thanks!
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 17/38] namei: introduce struct renamedata
2020-12-01 10:53 ` Christoph Hellwig
@ 2020-12-02 9:18 ` Christian Brauner
0 siblings, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-02 9:18 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Tue, Dec 01, 2020 at 11:53:36AM +0100, Christoph Hellwig wrote:
> > +int vfs_rename(struct renamedata *rd)
> > {
> > int error;
> > struct user_namespace *user_ns = &init_user_ns;
> > + struct inode *old_dir = rd->old_dir, *new_dir = rd->new_dir;
> > + struct dentry *old_dentry = rd->old_dentry,
> > + *new_dentry = rd->new_dentry;
>
> This looks weird. I'd just write the obvious:
>
> struct dentry *old_dentry = rd->old_dentry;
> struct dentry *new_dentry = rd->new_dentry;
Fixed.
Thanks!
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 07/38] mount: attach mappings to mounts
2020-12-01 10:50 ` Christoph Hellwig
2020-12-01 13:25 ` Tycho Andersen
@ 2020-12-02 9:24 ` Christian Brauner
1 sibling, 0 replies; 73+ messages in thread
From: Christian Brauner @ 2020-12-02 9:24 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Tue, Dec 01, 2020 at 11:50:25AM +0100, Christoph Hellwig wrote:
> The READ_ONCE still looks suspect as it generally needs to be paired
> with a WRITE_ONCE. The rest looks sane to me.
I think the READ_ONCE() can be dropped from this patch. At this point in
the series we don't allowing changing the vfsmount's userns. The infra
to do that is only introduced as almost the last patch in the series and
there we immediately use smp_load_acquire() and smp_store_release().
Thanks!
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 04/38] fs: add mount_setattr()
2020-12-01 10:49 ` Christoph Hellwig
@ 2020-12-02 9:42 ` Christian Brauner
2020-12-02 9:47 ` Christoph Hellwig
0 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-12-02 9:42 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Tue, Dec 01, 2020 at 11:49:07AM +0100, Christoph Hellwig wrote:
Sorry for not responding to this yesterday. I missed most of your mails
because they have been filtered into a dedicated folder (as they should
be) and I would've looked into that folder but somehow gmail let ~3
mails of you into my general inbox and so I didn't bother...
> Lots of crazy long lines in the patch. Remember that you should only
> go past 80 lines if it clearly improves readability, and I don't
> think it does anywhere in here.
Weird, I did reformat the patch to the 80 char limit and I have dual
display in vim, meaning I have a visible line at 80 chars and 100 chars
whenever I edit a file. I'll go through it again, thanks!
>
> > index a7cd0f64faa4..a5a6c470dc07 100644
> > --- a/fs/internal.h
> > +++ b/fs/internal.h
> > @@ -82,6 +82,14 @@ int may_linkat(struct path *link);
> > /*
> > * namespace.c
> > */
> > +struct mount_kattr {
> > + unsigned int attr_set;
> > + unsigned int attr_clr;
> > + unsigned int propagation;
> > + unsigned int lookup_flags;
> > + bool recurse;
> > +};
>
> Even with the whole series applied this structure is only used in
> namespace.c, so it might be worth moving there.
Good point. Will do.
>
> > +static inline int mnt_hold_writers(struct mount *mnt)
> > {
> > - int ret = 0;
> > -
> > mnt->mnt.mnt_flags |= MNT_WRITE_HOLD;
> > /*
> > * After storing MNT_WRITE_HOLD, we'll read the counters. This store
> > @@ -497,15 +495,29 @@ static int mnt_make_readonly(struct mount *mnt)
> > * we're counting up here.
> > */
> > if (mnt_get_writers(mnt) > 0)
> > - ret = -EBUSY;
> > - else
> > - mnt->mnt.mnt_flags |= MNT_READONLY;
> > + return -EBUSY;
> > +
> > + return 0;
> > +}
> > +
> > +static inline void mnt_unhold_writers(struct mount *mnt)
> > +{
> > /*
> > * MNT_READONLY must become visible before ~MNT_WRITE_HOLD, so writers
> > * that become unheld will see MNT_READONLY.
> > */
> > smp_wmb();
> > mnt->mnt.mnt_flags &= ~MNT_WRITE_HOLD;
> > +}
> > +
> > +static int mnt_make_readonly(struct mount *mnt)
> > +{
> > + int ret;
> > +
> > + ret = mnt_hold_writers(mnt);
> > + if (!ret)
> > + mnt->mnt.mnt_flags |= MNT_READONLY;
> > + mnt_unhold_writers(mnt);
> > return ret;
> > }
> >
> > @@ -3438,6 +3450,33 @@ SYSCALL_DEFINE5(mount, char __user *, dev_name, char __user *, dir_name,
> > return ret;
> > }
>
> This refactoring seems worth a little prep patch.
Will split into separate patch.
>
> >
> > +static int build_attr_flags(unsigned int attr_flags, unsigned int *flags)
> > +{
> > + unsigned int aflags = 0;
> > +
> > + if (attr_flags & ~(MOUNT_ATTR_RDONLY |
> > + MOUNT_ATTR_NOSUID |
> > + MOUNT_ATTR_NODEV |
> > + MOUNT_ATTR_NOEXEC |
> > + MOUNT_ATTR__ATIME |
> > + MOUNT_ATTR_NODIRATIME))
> > + return -EINVAL;
> > +
> > + if (attr_flags & MOUNT_ATTR_RDONLY)
> > + aflags |= MNT_READONLY;
> > + if (attr_flags & MOUNT_ATTR_NOSUID)
> > + aflags |= MNT_NOSUID;
> > + if (attr_flags & MOUNT_ATTR_NODEV)
> > + aflags |= MNT_NODEV;
> > + if (attr_flags & MOUNT_ATTR_NOEXEC)
> > + aflags |= MNT_NOEXEC;
> > + if (attr_flags & MOUNT_ATTR_NODIRATIME)
> > + aflags |= MNT_NODIRATIME;
> > +
> > + *flags = aflags;
> > + return 0;
> > +}
>
> Same for adding this helper.
Will do.
>
> > + *kattr = (struct mount_kattr){
>
> Missing whitespace before the {.
Good spot, thank you!
>
> > + switch (attr->propagation) {
> > + case MAKE_PROPAGATION_UNCHANGED:
> > + kattr->propagation = 0;
> > + break;
> > + case MAKE_PROPAGATION_UNBINDABLE:
> > + kattr->propagation = MS_UNBINDABLE;
> > + break;
> > + case MAKE_PROPAGATION_PRIVATE:
> > + kattr->propagation = MS_PRIVATE;
> > + break;
> > + case MAKE_PROPAGATION_DEPENDENT:
> > + kattr->propagation = MS_SLAVE;
> > + break;
> > + case MAKE_PROPAGATION_SHARED:
> > + kattr->propagation = MS_SHARED;
> > + break;
> > + default:
>
> Any reason to not just reuse the MS_* flags in the new API? Yes, your
> new names are more descriptive, but having different names for the same
> thing is also rather confusing.
I'm not really married to this so I don't see a reason why not.
>
> > + if (upper_32_bits(attr->attr_set))
> > + return -EINVAL;
> > + if (build_attr_flags(lower_32_bits(attr->attr_set), &kattr->attr_set))
> > + return -EINVAL;
> > +
> > + if (upper_32_bits(attr->attr_clr))
> > + return -EINVAL;
> > + if (build_attr_flags(lower_32_bits(attr->attr_clr), &kattr->attr_clr))
> > + return -EINVAL;
>
> What is so magic about the upper and lower 32 bits?
Nothing apart from the fact that they arent't currently valid. I can
think about reworking these lines. Or do you already have a preferred
way of doing this in mind?
>
> > + return -EINVAL;
> > + else if ((attr->attr_clr & MOUNT_ATTR__ATIME) &&
> > + ((attr->attr_clr & MOUNT_ATTR__ATIME) != MOUNT_ATTR__ATIME))
> > + return -EINVAL;
>
> No need for the else here.
Thanks!
>
> That being said I'd reword the thing to be a little more obvious:
>
> if (attr->attr_clr & MOUNT_ATTR__ATIME) {
> if ((attr->attr_clr & MOUNT_ATTR__ATIME) != MOUNT_ATTR__ATIME)
> return -EINVAL;
>
> ... code doing the update of the atime flags here
> } else {
> if (attr->attr_set & MOUNT_ATTR__ATIME)
> return -EINVAL;
> }
Will do.
>
>
> > +/* Change propagation through mount_setattr(). */
> > +enum propagation_type {
> > + MAKE_PROPAGATION_UNCHANGED = 0, /* Don't change mount propagation (default). */
> > + MAKE_PROPAGATION_UNBINDABLE = 1, /* Make unbindable. */
> > + MAKE_PROPAGATION_PRIVATE = 2, /* Do not receive or send mount events. */
> > + MAKE_PROPAGATION_DEPENDENT = 3, /* Only receive mount events. */
> > + MAKE_PROPAGATION_SHARED = 4, /* Send and receive mount events. */
> > +};
>
> FYI, in uapis using defines instead of enums is usually the better
> choice, as that allows userspace to probe for later added defines.
>
> But if we use MS_* here that would be void anyway.
Indeed.
>
> > +/* List of all mount_attr versions. */
> > +#define MOUNT_ATTR_SIZE_VER0 24 /* sizeof first published struct */
> > +#define MOUNT_ATTR_SIZE_LATEST MOUNT_ATTR_SIZE_VER0
>
> The _LATEST things is pretty dangerous as there basically is no safe
> and correct way for userspace to use it.
Ok, I'll remove the _LATEST.
Thanks for the review (and sorry again for missing your mails)!
Christian
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 04/38] fs: add mount_setattr()
2020-12-02 9:42 ` Christian Brauner
@ 2020-12-02 9:47 ` Christoph Hellwig
2020-12-02 9:55 ` Christoph Hellwig
0 siblings, 1 reply; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-02 9:47 UTC (permalink / raw)
To: Christian Brauner
Cc: Christoph Hellwig, Alexander Viro, Christoph Hellwig,
linux-fsdevel, John Johansen, James Morris, Mimi Zohar,
Dmitry Kasatkin, Stephen Smalley, Casey Schaufler, Arnd Bergmann,
Andreas Dilger, OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel,
Josh Triplett, Andy Lutomirski, Theodore Tso, Alban Crequy,
Tycho Andersen, David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux
On Wed, Dec 02, 2020 at 10:42:18AM +0100, Christian Brauner wrote:
> > > + if (upper_32_bits(attr->attr_set))
> > > + return -EINVAL;
> > > + if (build_attr_flags(lower_32_bits(attr->attr_set), &kattr->attr_set))
> > > + return -EINVAL;
> > > +
> > > + if (upper_32_bits(attr->attr_clr))
> > > + return -EINVAL;
> > > + if (build_attr_flags(lower_32_bits(attr->attr_clr), &kattr->attr_clr))
> > > + return -EINVAL;
> >
> > What is so magic about the upper and lower 32 bits?
>
> Nothing apart from the fact that they arent't currently valid. I can
> think about reworking these lines. Or do you already have a preferred
> way of doing this in mind?
Just turn the attr_flags argument to build_attr_flags into a u64 and
the first sanity check there will catch all invalid flags, no matter
where they are places. That should also generate more efficient code.
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 04/38] fs: add mount_setattr()
2020-12-02 9:47 ` Christoph Hellwig
@ 2020-12-02 9:55 ` Christoph Hellwig
2020-12-02 9:57 ` Christian Brauner
0 siblings, 1 reply; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-02 9:55 UTC (permalink / raw)
To: Christian Brauner
Cc: Christoph Hellwig, Alexander Viro, Christoph Hellwig,
linux-fsdevel, John Johansen, James Morris, Mimi Zohar,
Dmitry Kasatkin, Stephen Smalley, Casey Schaufler, Arnd Bergmann,
Andreas Dilger, OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel,
Josh Triplett, Andy Lutomirski, Theodore Tso, Alban Crequy,
Tycho Andersen, David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux
On Wed, Dec 02, 2020 at 10:47:51AM +0100, Christoph Hellwig wrote:
> On Wed, Dec 02, 2020 at 10:42:18AM +0100, Christian Brauner wrote:
> > > > + if (upper_32_bits(attr->attr_set))
> > > > + return -EINVAL;
> > > > + if (build_attr_flags(lower_32_bits(attr->attr_set), &kattr->attr_set))
> > > > + return -EINVAL;
> > > > +
> > > > + if (upper_32_bits(attr->attr_clr))
> > > > + return -EINVAL;
> > > > + if (build_attr_flags(lower_32_bits(attr->attr_clr), &kattr->attr_clr))
> > > > + return -EINVAL;
> > >
> > > What is so magic about the upper and lower 32 bits?
> >
> > Nothing apart from the fact that they arent't currently valid. I can
> > think about reworking these lines. Or do you already have a preferred
> > way of doing this in mind?
>
> Just turn the attr_flags argument to build_attr_flags into a u64 and
> the first sanity check there will catch all invalid flags, no matter
> where they are places. That should also generate more efficient code.
And while we're at it: the check for valid flags in the current
code is a little weird, given that build_attr_flags checks for
them, and but sys_fsmount also has its own slightly narrower checks.
I think it might make sense to split the validity check out of
build_attr_flags. E.g. something like:
static unsigned int attr_flags_to_mnt_flags(u64 attr_flags)
{
unsigned int mnt_flags = 0;
if (attr_flags & MOUNT_ATTR_RDONLY)
mnt_flags |= MNT_READONLY;
if (attr_flags & MOUNT_ATTR_NOSUID)
mnt_flags |= MNT_NOSUID;
if (attr_flags & MOUNT_ATTR_NODEV)
mnt_flags |= MNT_NODEV;
if (attr_flags & MOUNT_ATTR_NOEXEC)
mnt_flags |= MNT_NOEXEC;
if (attr_flags & MOUNT_ATTR_NODIRATIME)
mnt_flags |= MNT_NODIRATIME;
return mnt_flags;
}
#define MOUNT_SETATTR_VALID_FLAGS \
(MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOSUID | MOUNT_ATTR_NODEV | \
MOUNT_ATTR_NOEXEC | MOUNT_ATTR__ATIME | MOUNT_ATTR_NODIRATIME | \
MOUNT_ATTR_IDMAP)
static int build_mount_kattr(const struct mount_attr *attr, size_t usize,
struct mount_kattr *kattr, unsigned int flags)
{
...
if ((attr->attr_set | attr->attr_clr) & ~MOUNT_SETATTR_VALID_FLAGS)
return -EINVAL;
kattr->attr_set = attr_flags_to_mnt_flags(attr->attr_set);
kattr->attr_clr = attr_flags_to_mnt_flags(attr->attr_clr);
...
}
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 04/38] fs: add mount_setattr()
2020-12-02 9:55 ` Christoph Hellwig
@ 2020-12-02 9:57 ` Christian Brauner
2020-12-02 10:01 ` Christoph Hellwig
0 siblings, 1 reply; 73+ messages in thread
From: Christian Brauner @ 2020-12-02 9:57 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Alexander Viro, Christoph Hellwig, linux-fsdevel, John Johansen,
James Morris, Mimi Zohar, Dmitry Kasatkin, Stephen Smalley,
Casey Schaufler, Arnd Bergmann, Andreas Dilger, OGAWA Hirofumi,
Geoffrey Thomas, Mrunal Patel, Josh Triplett, Andy Lutomirski,
Theodore Tso, Alban Crequy, Tycho Andersen, David Howells,
James Bottomley, Seth Forshee, Stéphane Graber,
Aleksa Sarai, Lennart Poettering, Eric W. Biederman, smbarber,
Phil Estes, Serge Hallyn, Kees Cook, Todd Kjos, Paul Moore,
Jonathan Corbet, containers, fstests, linux-security-module,
linux-api, linux-ext4, linux-integrity, selinux
On Wed, Dec 02, 2020 at 10:55:47AM +0100, Christoph Hellwig wrote:
> On Wed, Dec 02, 2020 at 10:47:51AM +0100, Christoph Hellwig wrote:
> > On Wed, Dec 02, 2020 at 10:42:18AM +0100, Christian Brauner wrote:
> > > > > + if (upper_32_bits(attr->attr_set))
> > > > > + return -EINVAL;
> > > > > + if (build_attr_flags(lower_32_bits(attr->attr_set), &kattr->attr_set))
> > > > > + return -EINVAL;
> > > > > +
> > > > > + if (upper_32_bits(attr->attr_clr))
> > > > > + return -EINVAL;
> > > > > + if (build_attr_flags(lower_32_bits(attr->attr_clr), &kattr->attr_clr))
> > > > > + return -EINVAL;
> > > >
> > > > What is so magic about the upper and lower 32 bits?
> > >
> > > Nothing apart from the fact that they arent't currently valid. I can
> > > think about reworking these lines. Or do you already have a preferred
> > > way of doing this in mind?
> >
> > Just turn the attr_flags argument to build_attr_flags into a u64 and
> > the first sanity check there will catch all invalid flags, no matter
> > where they are places. That should also generate more efficient code.
>
> And while we're at it: the check for valid flags in the current
> code is a little weird, given that build_attr_flags checks for
> them, and but sys_fsmount also has its own slightly narrower checks.
>
> I think it might make sense to split the validity check out of
> build_attr_flags. E.g. something like:
Sounds good!
If we make this a preparatory patch do you want to be recorded in the
author field?
>
> static unsigned int attr_flags_to_mnt_flags(u64 attr_flags)
> {
> unsigned int mnt_flags = 0;
>
> if (attr_flags & MOUNT_ATTR_RDONLY)
> mnt_flags |= MNT_READONLY;
> if (attr_flags & MOUNT_ATTR_NOSUID)
> mnt_flags |= MNT_NOSUID;
> if (attr_flags & MOUNT_ATTR_NODEV)
> mnt_flags |= MNT_NODEV;
> if (attr_flags & MOUNT_ATTR_NOEXEC)
> mnt_flags |= MNT_NOEXEC;
> if (attr_flags & MOUNT_ATTR_NODIRATIME)
> mnt_flags |= MNT_NODIRATIME;
>
> return mnt_flags;
> }
>
> #define MOUNT_SETATTR_VALID_FLAGS \
> (MOUNT_ATTR_RDONLY | MOUNT_ATTR_NOSUID | MOUNT_ATTR_NODEV | \
> MOUNT_ATTR_NOEXEC | MOUNT_ATTR__ATIME | MOUNT_ATTR_NODIRATIME | \
> MOUNT_ATTR_IDMAP)
>
> static int build_mount_kattr(const struct mount_attr *attr, size_t usize,
> struct mount_kattr *kattr, unsigned int flags)
> {
> ...
>
> if ((attr->attr_set | attr->attr_clr) & ~MOUNT_SETATTR_VALID_FLAGS)
> return -EINVAL;
> kattr->attr_set = attr_flags_to_mnt_flags(attr->attr_set);
> kattr->attr_clr = attr_flags_to_mnt_flags(attr->attr_clr);
> ...
> }
^ permalink raw reply [flat|nested] 73+ messages in thread
* Re: [PATCH v3 04/38] fs: add mount_setattr()
2020-12-02 9:57 ` Christian Brauner
@ 2020-12-02 10:01 ` Christoph Hellwig
0 siblings, 0 replies; 73+ messages in thread
From: Christoph Hellwig @ 2020-12-02 10:01 UTC (permalink / raw)
To: Christian Brauner
Cc: Christoph Hellwig, Alexander Viro, Christoph Hellwig,
linux-fsdevel, John Johansen, James Morris, Mimi Zohar,
Dmitry Kasatkin, Stephen Smalley, Casey Schaufler, Arnd Bergmann,
Andreas Dilger, OGAWA Hirofumi, Geoffrey Thomas, Mrunal Patel,
Josh Triplett, Andy Lutomirski, Theodore Tso, Alban Crequy,
Tycho Andersen, David Howells, James Bottomley, Seth Forshee,
Stéphane Graber, Aleksa Sarai, Lennart Poettering,
Eric W. Biederman, smbarber, Phil Estes, Serge Hallyn, Kees Cook,
Todd Kjos, Paul Moore, Jonathan Corbet, containers, fstests,
linux-security-module, linux-api, linux-ext4, linux-integrity,
selinux
On Wed, Dec 02, 2020 at 10:57:45AM +0100, Christian Brauner wrote:
> Sounds good!
> If we make this a preparatory patch do you want to be recorded in the
> author field?
No need to record me in any way. This was just whiteboard coding.
^ permalink raw reply [flat|nested] 73+ messages in thread
end of thread, other threads:[~2020-12-02 10:02 UTC | newest]
Thread overview: 73+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-11-28 21:34 [PATCH v3 00/38] idmapped mounts Christian Brauner
2020-11-28 21:34 ` [PATCH v3 01/38] namespace: take lock_mount_hash() directly when changing flags Christian Brauner
2020-12-01 10:31 ` Christoph Hellwig
2020-12-02 9:09 ` Christian Brauner
2020-11-28 21:34 ` [PATCH v3 02/38] mount: make {lock,unlock}_mount_hash() static Christian Brauner
2020-12-01 10:32 ` Christoph Hellwig
2020-12-02 9:11 ` Christian Brauner
2020-11-28 21:34 ` [PATCH v3 03/38] namespace: only take read lock in do_reconfigure_mnt() Christian Brauner
2020-12-01 10:32 ` Christoph Hellwig
2020-12-02 9:14 ` Christian Brauner
2020-11-28 21:34 ` [PATCH v3 04/38] fs: add mount_setattr() Christian Brauner
2020-12-01 10:49 ` Christoph Hellwig
2020-12-02 9:42 ` Christian Brauner
2020-12-02 9:47 ` Christoph Hellwig
2020-12-02 9:55 ` Christoph Hellwig
2020-12-02 9:57 ` Christian Brauner
2020-12-02 10:01 ` Christoph Hellwig
2020-11-28 21:34 ` [PATCH v3 05/38] tests: add mount_setattr() selftests Christian Brauner
2020-11-28 21:34 ` [PATCH v3 06/38] fs: add id translation helpers Christian Brauner
2020-12-01 10:49 ` Christoph Hellwig
2020-12-02 9:16 ` Christian Brauner
2020-11-28 21:34 ` [PATCH v3 07/38] mount: attach mappings to mounts Christian Brauner
2020-12-01 10:50 ` Christoph Hellwig
2020-12-01 13:25 ` Tycho Andersen
2020-12-02 9:24 ` Christian Brauner
2020-11-28 21:34 ` [PATCH v3 08/38] capability: handle idmapped mounts Christian Brauner
2020-11-28 22:34 ` Serge E. Hallyn
2020-11-28 21:34 ` [PATCH v3 09/38] namei: add idmapped mount aware permission helpers Christian Brauner
2020-11-28 22:47 ` Serge E. Hallyn
2020-12-01 10:58 ` Christian Brauner
2020-12-01 10:51 ` Christoph Hellwig
2020-12-01 10:58 ` Christian Brauner
2020-11-28 21:34 ` [PATCH v3 10/38] inode: add idmapped mount aware init and " Christian Brauner
2020-12-01 10:51 ` Christoph Hellwig
2020-12-02 9:17 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 11/38] attr: handle idmapped mounts Christian Brauner
2020-11-28 21:35 ` [PATCH v3 12/38] acl: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 13/38] xattr: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 14/38] commoncap: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 15/38] stat: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 16/38] namei: handle idmapped mounts in may_*() helpers Christian Brauner
2020-11-28 21:35 ` [PATCH v3 17/38] namei: introduce struct renamedata Christian Brauner
2020-12-01 10:53 ` Christoph Hellwig
2020-12-02 9:18 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 18/38] namei: prepare for idmapped mounts Christian Brauner
2020-11-28 21:35 ` [PATCH v3 19/38] open: handle idmapped mounts in do_truncate() Christian Brauner
2020-11-28 21:35 ` [PATCH v3 20/38] open: handle idmapped mounts Christian Brauner
2020-11-28 21:35 ` [PATCH v3 21/38] af_unix: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 22/38] utimes: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 23/38] fcntl: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 24/38] notify: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 25/38] init: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 26/38] ioctl: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 27/38] would_dump: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 28/38] exec: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 30/38] apparmor: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 31/38] ima: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 32/38] fat: " Christian Brauner
2020-11-30 22:50 ` Mauricio Vásquez Bernal
2020-12-01 10:24 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 33/38] ext4: support " Christian Brauner
2020-11-30 22:52 ` Mauricio Vásquez Bernal
2020-12-01 10:28 ` Christian Brauner
2020-12-01 10:54 ` Christoph Hellwig
2020-12-01 11:02 ` Christian Brauner
2020-12-01 11:13 ` Christoph Hellwig
2020-12-01 11:14 ` Christian Brauner
2020-11-28 21:35 ` [PATCH v3 34/38] ecryptfs: do not mount on top of " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 35/38] overlayfs: " Christian Brauner
2020-11-28 21:35 ` [PATCH v3 36/38] fs: introduce MOUNT_ATTR_IDMAP Christian Brauner
2020-11-28 21:35 ` [PATCH v3 37/38] tests: extend mount_setattr tests Christian Brauner
2020-11-28 22:54 ` [PATCH v3 00/38] idmapped mounts Serge E. Hallyn
2020-12-01 10:18 ` Christian Brauner
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