From: Jan Kara <jack@suse.cz>
Date: Wed, 23 Jan 2013 12:56:18 +0000 (+0100)
Subject: xfs: Fix possible use-after-free with AIO
X-Git-Tag: v3.2.38~27
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=e807626e32eb159914cee54473d17082a1920039;p=thirdparty%2Fkernel%2Fstable.git

xfs: Fix possible use-after-free with AIO

commit 4b05d09c18d9aa62d2e7fb4b057f54e5a38963f5 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.

CC: xfs@oss.sgi.com
CC: Ben Myers <bpm@sgi.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index 574d4ee9b6253..b3675816aca7a 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -88,11 +88,11 @@ xfs_destroy_ioend(
 	}
 
 	if (ioend->io_iocb) {
+		inode_dio_done(ioend->io_inode);
 		if (ioend->io_isasync) {
 			aio_complete(ioend->io_iocb, ioend->io_error ?
 					ioend->io_error : ioend->io_result, 0);
 		}
-		inode_dio_done(ioend->io_inode);
 	}
 
 	mempool_free(ioend, xfs_ioend_pool);