This is a note to let you know that I've just added the patch titled
should_follow_link(): validate ->d_seq after having decided to follow
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
should_follow_link-validate-d_seq-after-having-decided-to-follow.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From a7f775428b8f5808815c0e3004020cedb94cbe3b Mon Sep 17 00:00:00 2001
From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Date: Sat, 27 Feb 2016 19:31:01 -0500
Subject: should_follow_link(): validate ->d_seq after having decided to follow
From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
commit a7f775428b8f5808815c0e3004020cedb94cbe3b upstream.
... otherwise d_is_symlink() above might have nothing to do with
the inode value we've got.
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/namei.c | 5 +++++
1 file changed, 5 insertions(+)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1711,6 +1711,11 @@ static inline int should_follow_link(str
return 0;
if (!follow)
return 0;
+ /* make sure that d_is_symlink above matches inode */
+ if (nd->flags & LOOKUP_RCU) {
+ if (read_seqcount_retry(&link->dentry->d_seq, seq))
+ return -ECHILD;
+ }
return pick_link(nd, link, inode, seq);
}
Patches currently in stable-queue which might be from viro@xxxxxxxxxxxxxxxxxx are
queue-4.4/make-sure-that-freeing-shmem-fast-symlinks-is-rcu-delayed.patch
queue-4.4/do_last-eloop-failure-exit-should-be-done-after-leaving-rcu-mode.patch
queue-4.4/bcache-fix-a-leak-in-bch_cached_dev_run.patch
queue-4.4/do_last-don-t-let-a-bogus-return-value-from-open-et.al.-to-confuse-us.patch
queue-4.4/locks-fix-unlock-when-fcntl_setlk-races-with-a-close.patch
queue-4.4/namei-d_inode-of-a-pinned-dentry-is-stable-only-for-positives.patch
queue-4.4/should_follow_link-validate-d_seq-after-having-decided-to-follow.patch
queue-4.4/uml-fix-hostfs-mknod.patch
queue-4.4/hpfs-don-t-truncate-the-file-when-delete-fails.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html