[ 3.5.y.z extended stable ] Patch "ext4: fix memory leak in xattr" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    ext4: fix memory leak in xattr

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From bff2263022e15641f15ec6721cef7026cf93d217 Mon Sep 17 00:00:00 2001
From: Dave Jones <davej at redhat.com>
Date: Thu, 10 Oct 2013 20:05:35 -0400
Subject: [PATCH] ext4: fix memory leak in xattr

commit 6e4ea8e33b2057b85d75175dd89b93f5e26de3bc upstream.

If we take the 2nd retry path in ext4_expand_extra_isize_ea, we
potentionally return from the function without having freed these
allocations.  If we don't do the return, we over-write the previous
allocation pointers, so we leak either way.

Spotted with Coverity.

[ Fixed by tytso to set is and bs to NULL after freeing these
  pointers, in case in the retry loop we later end up triggering an
  error causing a jump to cleanup, at which point we could have a double
  free bug. -- Ted ]

Signed-off-by: Dave Jones <davej at fedoraproject.org>
Signed-off-by: "Theodore Ts'o" <tytso at mit.edu>
Reviewed-by: Eric Sandeen <sandeen at redhat.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 fs/ext4/xattr.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index 1d261e6..e979d5d 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -1328,6 +1328,8 @@ retry:
 				    s_min_extra_isize) {
 					tried_min_extra_isize++;
 					new_extra_isize = s_min_extra_isize;
+					kfree(is); is = NULL;
+					kfree(bs); bs = NULL;
 					goto retry;
 				}
 				error = -1;
--
1.8.3.2