Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932572Ab1DMQJ1 (ORCPT ); Wed, 13 Apr 2011 12:09:27 -0400 Received: from kroah.org ([198.145.64.141]:54265 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757741Ab1DMPzR (ORCPT ); Wed, 13 Apr 2011 11:55:17 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Apr 13 08:51:44 2011 Message-Id: <20110413155144.895499184@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Wed, 13 Apr 2011 08:50:42 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Dan Rosenberg , Alex Elder Subject: [18/74] xfs: prevent leaking uninitialized stack memory in FSGEOMETRY_V1 In-Reply-To: <20110413155406.GA22568@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1422 Lines: 45 2.6.32-longterm review patch. If anyone has any objections, please let us know. ------------------ From: Dan Rosenberg commit c4d0c3b097f7584772316ee4d64a09fe0e4ddfca upstream. The FSGEOMETRY_V1 ioctl (and its compat equivalent) calls out to xfs_fs_geometry() with a version number of 3. This code path does not fill in the logsunit member of the passed xfs_fsop_geom_t, leading to the leaking of four bytes of uninitialized stack data to potentially unprivileged callers. v2 switches to memset() to avoid future issues if structure members change, on suggestion of Dave Chinner. Signed-off-by: Dan Rosenberg Reviewed-by: Eugene Teo Signed-off-by: Alex Elder Signed-off-by: Greg Kroah-Hartman --- fs/xfs/xfs_fsops.c | 3 +++ 1 file changed, 3 insertions(+) --- a/fs/xfs/xfs_fsops.c +++ b/fs/xfs/xfs_fsops.c @@ -56,6 +56,9 @@ xfs_fs_geometry( xfs_fsop_geom_t *geo, int new_version) { + + memset(geo, 0, sizeof(*geo)); + geo->blocksize = mp->m_sb.sb_blocksize; geo->rtextsize = mp->m_sb.sb_rextsize; geo->agblocks = mp->m_sb.sb_agblocks; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/