Re: [PATCH] ext4: fix NULL pointer dereference in ext4_quota_off

[Ted Ts'o <tytso@mit.edu>]

On Mon, May 16, 2011 at 12:11:54PM +0200, Jan Kara wrote:
>   Ah, I see we worked on the patch together :). Anyway, Ted can pick any of
> them I guess.

I actually combined the commit description and used elements from both
of them.  Jan's short description was a better summary, but I liked
Amir description of the commit (note though that if you're going to
use abberviated git commit id's, please don't shorten them to 10-12
characters since given the size of the git repository, shorter git
commit id's could suffer from hash collision).

						- Ted

ext4: fix oops in ext4_quota_off()

From: Amir Goldstein <amir73il@gmail.com>

If quota is not enabled when ext4_quota_off() is called, we must not
dereference quota file inode since it is NULL.  Check properly for
this.

This fixes a bug in commit 21f976975cbe (ext4: remove unnecessary
[cm]time update of quota file), which was merged for 2.6.39-rc3.

Reported-by: Amir Goldstein <amir73il@users.sf.net>
Signed-off-by: Amir Goldstein <amir73il@users.sf.net>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

						- Ted