From: Willy Tarreau <w@1wt.eu>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
Al Viro <viro@zeniv.linux.org.uk>,
Ben Hutchings <ben@decadent.org.uk>, Willy Tarreau <w@1wt.eu>
Subject: [PATCH 2.6.32 01/38] [PATCH 01/38] dcache: Handle escaped paths in prepend_path
Date: Sun, 29 Nov 2015 22:47:03 +0100 [thread overview]
Message-ID: <20151129214702.918472379@1wt.eu> (raw)
In-Reply-To: <8acf8256ccc72771a80b7851061027bc@local>
2.6.32-longterm review patch. If anyone has any objections, please let me know.
------------------
commit cde93be45a8a90d8c264c776fab63487b5038a65 upstream.
A rename can result in a dentry that by walking up d_parent
will never reach it's mnt_root. For lack of a better term
I call this an escaped path.
prepend_path is called by four different functions __d_path,
d_absolute_path, d_path, and getcwd.
__d_path only wants to see paths are connected to the root it passes
in. So __d_path needs prepend_path to return an error.
d_absolute_path similarly wants to see paths that are connected to
some root. Escaped paths are not connected to any mnt_root so
d_absolute_path needs prepend_path to return an error greater
than 1. So escaped paths will be treated like paths on lazily
unmounted mounts.
getcwd needs to prepend "(unreachable)" so getcwd also needs
prepend_path to return an error.
d_path is the interesting hold out. d_path just wants to print
something, and does not care about the weird cases. Which raises
the question what should be printed?
Given that <escaped_path>/<anything> should result in -ENOENT I
believe it is desirable for escaped paths to be printed as empty
paths. As there are not really any meaninful path components when
considered from the perspective of a mount tree.
So tweak prepend_path to return an empty path with an new error
code of 3 when it encounters an escaped path.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[bwh: For 2.6.32, implement the "(unreachable)" string in __d_path()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
fs/dcache.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/fs/dcache.c b/fs/dcache.c
index 44c0aea..07c4472 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -1910,7 +1910,7 @@ char *__d_path(const struct path *path, struct path *root,
struct dentry *dentry = path->dentry;
struct vfsmount *vfsmnt = path->mnt;
char *end = buffer + buflen;
- char *retval;
+ char *retval, *tail;
spin_lock(&vfsmount_lock);
prepend(&end, &buflen, "\0", 1);
@@ -1923,6 +1923,7 @@ char *__d_path(const struct path *path, struct path *root,
/* Get '/' right */
retval = end-1;
*retval = '/';
+ tail = end;
for (;;) {
struct dentry * parent;
@@ -1930,6 +1931,14 @@ char *__d_path(const struct path *path, struct path *root,
if (dentry == root->dentry && vfsmnt == root->mnt)
break;
if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) {
+ /* Escaped? */
+ if (dentry != vfsmnt->mnt_root) {
+ buflen += (tail - end);
+ end = tail;
+ prepend(&end, &buflen, "(unreachable)/", 14);
+ retval = end;
+ goto out;
+ }
/* Global root? */
if (vfsmnt->mnt_parent == vfsmnt) {
goto global_root;
--
1.7.12.2.21.g234cd45.dirty
next prev parent reply other threads:[~2015-11-29 22:00 UTC|newest]
Thread overview: 57+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <8acf8256ccc72771a80b7851061027bc@local>
2015-11-29 21:47 ` [PATCH 2.6.32 00/38] 2.6.32.69-longterm review Willy Tarreau
2015-11-29 21:47 ` Willy Tarreau [this message]
2015-11-29 21:47 ` [PATCH 2.6.32 03/38] [PATCH 03/38] md: use kzalloc() when bitmap is disabled Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 04/38] [PATCH 04/38] ipv6: addrconf: validate new MTU before applying it Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 05/38] [PATCH 05/38] virtio-net: drop NETIF_F_FRAGLIST Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 06/38] [PATCH 06/38] USB: whiteheat: fix potential null-deref at probe Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 07/38] [PATCH 07/38] ipc/sem.c: fully initialize sem_array before making it visible Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 08/38] [PATCH 08/38] Initialize msg/shm IPC objects before doing ipc_addid() Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 10/38] [PATCH 10/38] rds: fix an integer overflow test in rds_info_getsockopt() Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 11/38] [PATCH 11/38] net: Clone skb before setting peeked flag Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 12/38] [PATCH 12/38] net: Fix skb_set_peeked use-after-free bug Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 13/38] [PATCH 13/38] ipc,sem: fix use after free on IPC_RMID after a task using same semaphore set exits Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 14/38] [PATCH 14/38] devres: fix devres_get() Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 15/38] [PATCH 15/38] windfarm: decrement client count when unregistering Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 16/38] [PATCH 16/38] xfs: Fix xfs_attr_leafblock definition Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 17/38] [PATCH 17/38] SUNRPC: xs_reset_transport must mark the connection as disconnected Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 18/38] [PATCH 18/38] Input: evdev - do not report errors form flush() Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 19/38] [PATCH 19/38] pagemap: hide physical addresses from non-privileged users Willy Tarreau
2015-11-30 1:54 ` Ben Hutchings
2015-11-30 7:01 ` Willy Tarreau
2015-11-30 11:30 ` Willy Tarreau
2015-11-30 11:49 ` Konstantin Khlebnikov
2015-11-30 12:13 ` Willy Tarreau
2015-11-30 14:55 ` Ben Hutchings
2015-11-30 15:14 ` Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 20/38] [PATCH 20/38] hfs,hfsplus: cache pages correctly between bnode_create and bnode_free Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 21/38] [PATCH 21/38] hfs: fix B-tree corruption after insertion at position 0 Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 22/38] [PATCH 22/38] x86/paravirt: Replace the paravirt nop with a bona fide empty function Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 23/38] [PATCH 23/38] RDS: verify the underlying transport exists before creating a connection Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 24/38] [PATCH 24/38] net: Fix skb csum races when peeking Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 25/38] [PATCH 25/38] net: add length argument to skb_copy_and_csum_datagram_iovec Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 26/38] [PATCH 26/38] module: Fix locking in symbol_put_addr() Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 27/38] [PATCH 27/38] x86/process: Add proper bound checks in 64bit get_wchan() Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 28/38] [PATCH 28/38] mm: hugetlbfs: skip shared VMAs when unmapping private pages to satisfy a fault Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 29/38] [PATCH 29/38] tty: fix stall caused by missing memory barrier in drivers/tty/n_tty.c Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 31/38] [PATCH 31/38] ethtool: Use kcalloc instead of kmalloc for ethtool_get_strings Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 32/38] [PATCH 32/38] HID: core: Avoid uninitialized buffer access Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 33/38] [PATCH 33/38] devres: fix a for loop bounds check Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 34/38] [PATCH 34/38] binfmt_elf: Dont clobber passed executables file header Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 35/38] [PATCH 35/38] RDS-TCP: Recover correctly from pskb_pull()/pksb_trim() failure in rds_tcp_data_recv Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 36/38] [PATCH 36/38] ipmr: fix possible race resulting from improper usage of IP_INC_STATS_BH() in preemptible context Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 37/38] [PATCH 37/38] net: avoid NULL deref in inet_ctl_sock_destroy() Willy Tarreau
2015-11-29 21:47 ` [PATCH 2.6.32 38/38] [PATCH 38/38] splice: sendfile() at once fails for big files Willy Tarreau
2015-11-30 1:25 ` [PATCH 2.6.32 09/38] [PATCH 09/38] xhci: fix off by one error in TRB DMA address boundary check Willy Tarreau
2015-11-30 2:04 ` [PATCH 2.6.32 30/38] [PATCH 30/38] mvsas: Fix NULL pointer dereference in mvs_slot_task_free Willy Tarreau
2015-11-30 2:42 ` [PATCH 2.6.32 00/38] 2.6.32.69-longterm review Ben Hutchings
2015-11-30 6:51 ` Willy Tarreau
2015-11-30 11:23 ` Willy Tarreau
2015-11-30 14:43 ` Ben Hutchings
2015-11-30 15:10 ` Willy Tarreau
[not found] ` <20151129214702.957590241@1wt.eu>
2015-11-30 6:44 ` [PATCH 2.6.32 02/38] [PATCH 02/38] Failing to send a CLOSE if file is opened WRONLY and server reboots on a 4.x mount Willy Tarreau
[not found] ` <abcd326bbd6833b04b56738cd1734419@local>
2015-11-30 16:04 ` [PATCH 2.6.32 00/38] 2.6.32.69-longterm review Willy Tarreau
2015-11-30 16:04 ` [PATCH 2.6.32 39/38] vfs: Test for and handle paths that are unreachable from their mnt_root Willy Tarreau
2015-11-30 16:05 ` [PATCH 2.6.32 40/38] security: add cred argument to security_capable() Willy Tarreau
2015-11-30 16:05 ` [PATCH 2.6.32 19/38] pagemap: hide physical addresses from non-privileged users Willy Tarreau
2015-12-01 0:43 ` [PATCH 2.6.32 00/38] 2.6.32.69-longterm review Ben Hutchings
2015-12-01 6:57 ` Willy Tarreau
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=20151129214702.918472379@1wt.eu \
--to=w@1wt.eu \
--cc=ben@decadent.org.uk \
--cc=ebiederm@xmission.com \
--cc=linux-kernel@vger.kernel.org \
--cc=stable@vger.kernel.org \
--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).