[PATCH 118/139] ocfs2: fix possible use-after-free with AIO

[Luis Henriques]

3.5.7.7 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jan Kara <jack at suse.cz>

commit 9b171e0c74ca0549d0610990a862dd895870f04a upstream.

Running AIO is pinning inode in memory using file reference. Once AIO
is completed using aio_complete(), file reference is put and inode can
be freed from memory. So we have to be sure that calling aio_complete()
is the last thing we do with the inode.

Signed-off-by: Jan Kara <jack at suse.cz>
Acked-by: Jeff Moyer <jmoyer at redhat.com>
Acked-by: Joel Becker <jlbec at evilplan.org>
Cc: Mark Fasheh <mfasheh at suse.com>
Cc: Al Viro <viro at zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
Signed-off-by: Al Viro <viro at zeniv.linux.org.uk>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 fs/ocfs2/aops.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 6577432..340bd02 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -593,9 +593,9 @@ static void ocfs2_dio_end_io(struct kiocb *iocb,
 	level = ocfs2_iocb_rw_locked_level(iocb);
 	ocfs2_rw_unlock(inode, level);
 
+	inode_dio_done(inode);
 	if (is_async)
 		aio_complete(iocb, ret, 0);
-	inode_dio_done(inode);
 }
 
 /*
-- 
1.8.1.2