diff options
author | Al Viro | 2018-10-05 20:29:46 +0200 |
---|---|---|
committer | Al Viro | 2018-10-05 20:37:28 +0200 |
commit | b07581d2d5add23ae163e3fbfb2fa5d36076922f (patch) | |
tree | 1e932e63894e23c27a6c332dedda164c02e78fbd /fs/ecryptfs | |
parent | sysfs: Do not return POSIX ACL xattrs via listxattr (diff) | |
download | kernel-qcow2-linux-b07581d2d5add23ae163e3fbfb2fa5d36076922f.tar.gz kernel-qcow2-linux-b07581d2d5add23ae163e3fbfb2fa5d36076922f.tar.xz kernel-qcow2-linux-b07581d2d5add23ae163e3fbfb2fa5d36076922f.zip |
cachefiles: fix the race between cachefiles_bury_object() and rmdir(2)
the victim might've been rmdir'ed just before the lock_rename();
unlike the normal callers, we do not look the source up after the
parents are locked - we know it beforehand and just recheck that it's
still the child of what used to be its parent. Unfortunately,
the check is too weak - we don't spot a dead directory since its
->d_parent is unchanged, dentry is positive, etc. So we sail all
the way to ->rename(), with hosting filesystems _not_ expecting
to be asked renaming an rmdir'ed subdirectory.
The fix is easy, fortunately - the lock on parent is sufficient for
making IS_DEADDIR() on child safe.
Cc: stable@vger.kernel.org
Fixes: 9ae326a69004 (CacheFiles: A cache that backs onto a mounted filesystem)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/ecryptfs')
0 files changed, 0 insertions, 0 deletions