From: Amir Goldstein <amir73il@gmail.com>
Date: Mon, 16 May 2011 13:59:13 +0000 (-0400)
Subject: ext4: fix oops in ext4_quota_off()
X-Git-Tag: firefly_0821_release~7613^2~1130^2~34
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0b26859027ce0005ef89520af20351360e51ad76;p=firefly-linux-kernel-4.4.55.git

ext4: fix oops in ext4_quota_off()

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>
---

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index fc827bb2a69b..268935118251 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -4681,6 +4681,9 @@ static int ext4_quota_off(struct super_block *sb, int type)
 	if (test_opt(sb, DELALLOC))
 		sync_filesystem(sb);
 
+	if (!inode)
+		goto out;
+
 	/* Update modification times of quota files when userspace can
 	 * start looking at them */
 	handle = ext4_journal_start(inode, 1);