xfs: fix acl count validation in xfs_acl_from_disk()
authorXi Wang <xi.wang@gmail.com>
Mon, 12 Dec 2011 21:55:52 +0000 (21:55 +0000)
committerGreg Kroah-Hartman <gregkh@suse.de>
Thu, 12 Jan 2012 19:33:47 +0000 (11:33 -0800)
commit723bf827f6d066a119f202131130af431dcc41a2
treef15e5156a7bc82dde5d453dd994899c9dee6ca0f
parent1820b28c96690ab8bc8977089d8eb4a9e7128117
xfs: fix acl count validation in xfs_acl_from_disk()

commit 093019cf1b18dd31b2c3b77acce4e000e2cbc9ce upstream.

Commit fa8b18ed didn't prevent the integer overflow and possible
memory corruption.  "count" can go negative and bypass the check.

Signed-off-by: Xi Wang <xi.wang@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
fs/xfs/xfs_acl.c