From: David Howells <dhowells@redhat.com>
To: viro@zeniv.linux.org.uk
Cc: dhowells@redhat.com, Casey Schaufler <casey@schaufler-ca.com>,
Stephen Smalley <sds@tycho.nsa.gov>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
nicolas.dichtel@6wind.com, raven@themaw.net,
Christian Brauner <christian@brauner.io>,
dhowells@redhat.com, keyrings@vger.kernel.org,
linux-usb@vger.kernel.org, linux-security-module@vger.kernel.org,
linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org,
linux-block@vger.kernel.org,
linux-security-module@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: [PATCH 0/6] Mount and superblock notifications [ver #5]
Date: Fri, 28 Jun 2019 16:50:13 +0100 [thread overview]
Message-ID: <156173701358.15650.8735203424342507015.stgit@warthog.procyon.org.uk> (raw)
Here's a set of patches to adds VFS-related watches to the general
notification system to add sources of events for:
(1) Mount topology events, such as mounting, unmounting, mount expiry,
mount reconfiguration.
(2) Superblock events, such as R/W<->R/O changes, quota overrun and I/O
errors (not complete yet).
One of the reasons for this is so that we can remove the issue of processes
having to repeatedly and regularly scan /proc/mounts, which has proven to
be a system performance problem. To further aid this, the fsinfo() syscall
on which this patch series depends, provides a way to access superblock and
mount information in binary form without the need to parse /proc/mounts.
LSM hooks are included are provided that allow an LSM to rule on whether or
not a watch may be set. Each of these hooks takes a different "watched
object" parameter, so they're not really shareable. The LSM should use
current's credentials. [Wanted by SELinux & Smack]
Watches are created with:
watch_mount(AT_FDCWD, "/", 0, fd, 0x03);
watch_sb(AT_FDCWD, "/mnt", 0, fd, 0x04);
where in all three cases, fd indicates the queue and the number after is a
tag between 0 and 255.
Further things that could be considered:
(1) Adding global superblock event queue.
(2) Propagating watches to child superblock over automounts.
The patches can be found here also:
http://git.kernel.org/cgit/linux/kernel/git/dhowells/linux-fs.git/log/?h=notifications
Changes:
ver #5:
(*) The superblock watch and mount watch parts are split out into this set
from the core branch (notifications-core) as it depends on fsinfo().
David
---
David Howells (6):
security: Add hooks to rule on setting a superblock or mount watch
Adjust watch_queue documentation to mention mount and superblock watches.
vfs: Add a mount-notification facility
vfs: Add superblock notifications
fsinfo: Export superblock notification counter
Add sample notification program
Documentation/watch_queue.rst | 20 +++
arch/alpha/kernel/syscalls/syscall.tbl | 2
arch/arm/tools/syscall.tbl | 2
arch/arm64/include/asm/unistd.h | 2
arch/ia64/kernel/syscalls/syscall.tbl | 2
arch/m68k/kernel/syscalls/syscall.tbl | 2
arch/microblaze/kernel/syscalls/syscall.tbl | 2
arch/mips/kernel/syscalls/syscall_n32.tbl | 2
arch/mips/kernel/syscalls/syscall_n64.tbl | 2
arch/mips/kernel/syscalls/syscall_o32.tbl | 2
arch/parisc/kernel/syscalls/syscall.tbl | 2
arch/powerpc/kernel/syscalls/syscall.tbl | 2
arch/s390/kernel/syscalls/syscall.tbl | 2
arch/sh/kernel/syscalls/syscall.tbl | 2
arch/sparc/kernel/syscalls/syscall.tbl | 2
arch/x86/entry/syscalls/syscall_32.tbl | 2
arch/x86/entry/syscalls/syscall_64.tbl | 2
arch/xtensa/kernel/syscalls/syscall.tbl | 2
drivers/misc/Kconfig | 5 -
fs/Kconfig | 21 +++
fs/Makefile | 1
fs/fsinfo.c | 12 ++
fs/mount.h | 33 +++--
fs/mount_notify.c | 188 +++++++++++++++++++++++++++
fs/namespace.c | 16 ++
fs/super.c | 126 ++++++++++++++++++
include/linux/dcache.h | 1
include/linux/fs.h | 78 +++++++++++
include/linux/lsm_hooks.h | 16 ++
include/linux/security.h | 10 +
include/linux/syscalls.h | 4 +
include/uapi/asm-generic/unistd.h | 6 +
include/uapi/linux/fsinfo.h | 10 +
include/uapi/linux/watch_queue.h | 61 +++++++++
kernel/sys_ni.c | 2
samples/vfs/test-fsinfo.c | 13 ++
samples/watch_queue/watch_test.c | 76 +++++++++++
security/security.c | 10 +
38 files changed, 722 insertions(+), 21 deletions(-)
create mode 100644 fs/mount_notify.c
next reply other threads:[~2019-06-28 15:50 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-28 15:50 David Howells [this message]
2019-06-28 15:50 ` [PATCH 1/6] security: Add hooks to rule on setting a superblock or mount watch [ver #5] David Howells
2019-07-12 20:11 ` James Morris
2019-06-28 15:50 ` [PATCH 2/6] Adjust watch_queue documentation to mention mount and superblock watches. " David Howells
2019-07-01 2:59 ` Randy Dunlap
2019-07-01 8:52 ` David Howells
2019-07-01 14:52 ` Randy Dunlap
2019-06-28 15:50 ` [PATCH 3/6] vfs: Add a mount-notification facility " David Howells
2019-06-28 15:50 ` [PATCH 4/6] vfs: Add superblock notifications " David Howells
2019-06-28 15:51 ` [PATCH 5/6] fsinfo: Export superblock notification counter " David Howells
2019-06-28 15:51 ` [PATCH 6/6] Add sample notification program " David Howells
2019-06-28 16:47 ` [PATCH 0/6] Mount and superblock notifications " David Howells
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=156173701358.15650.8735203424342507015.stgit@warthog.procyon.org.uk \
--to=dhowells@redhat.com \
--cc=casey@schaufler-ca.com \
--cc=christian@brauner.io \
--cc=gregkh@linuxfoundation.org \
--cc=keyrings@vger.kernel.org \
--cc=linux-api@vger.kernel.org \
--cc=linux-block@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=nicolas.dichtel@6wind.com \
--cc=raven@themaw.net \
--cc=sds@tycho.nsa.gov \
--cc=viro@zeniv.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).