From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754786AbaELCKY (ORCPT ); Sun, 11 May 2014 22:10:24 -0400 Received: from 1wt.eu ([62.212.114.60]:34508 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752708AbaELBmQ (ORCPT ); Sun, 11 May 2014 21:42:16 -0400 Message-Id: <20140512003206.396224510@1wt.eu> User-Agent: quilt/0.48-1 Date: Mon, 12 May 2014 02:34:17 +0200 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Dan Carpenter , Ben Myers , Willy Tarreau Subject: [ 137/143] xfs: underflow bug in xfs_attrlist_by_handle() In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter If we allocate less than sizeof(struct attrlist) then we end up corrupting memory or doing a ZERO_PTR_SIZE dereference. This can only be triggered with CAP_SYS_ADMIN. Reported-by: Nico Golde Reported-by: Fabian Yamaguchi Signed-off-by: Dan Carpenter Reviewed-by: Dave Chinner Signed-off-by: Ben Myers (cherry picked from commit 071c529eb672648ee8ca3f90944bcbcc730b4c06) [dannf: backported to Debian's 2.6.32] Signed-off-by: Willy Tarreau --- fs/xfs/linux-2.6/xfs_ioctl.c | 3 ++- fs/xfs/linux-2.6/xfs_ioctl32.c | 4 ++-- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/fs/xfs/linux-2.6/xfs_ioctl.c b/fs/xfs/linux-2.6/xfs_ioctl.c index 942362f..5663351 100644 --- a/fs/xfs/linux-2.6/xfs_ioctl.c +++ b/fs/xfs/linux-2.6/xfs_ioctl.c @@ -410,7 +410,8 @@ xfs_attrlist_by_handle( return -XFS_ERROR(EPERM); if (copy_from_user(&al_hreq, arg, sizeof(xfs_fsop_attrlist_handlereq_t))) return -XFS_ERROR(EFAULT); - if (al_hreq.buflen > XATTR_LIST_MAX) + if (al_hreq.buflen < sizeof(struct attrlist) || + al_hreq.buflen > XATTR_LIST_MAX) return -XFS_ERROR(EINVAL); /* diff --git a/fs/xfs/linux-2.6/xfs_ioctl32.c b/fs/xfs/linux-2.6/xfs_ioctl32.c index bad485a..782d03d 100644 --- a/fs/xfs/linux-2.6/xfs_ioctl32.c +++ b/fs/xfs/linux-2.6/xfs_ioctl32.c @@ -361,8 +361,8 @@ xfs_compat_attrlist_by_handle( if (copy_from_user(&al_hreq, arg, sizeof(compat_xfs_fsop_attrlist_handlereq_t))) return -XFS_ERROR(EFAULT); - if (al_hreq.buflen > XATTR_LIST_MAX) - return -XFS_ERROR(EINVAL); + if (al_hreq.buflen < sizeof(struct attrlist) || + al_hreq.buflen > XATTR_LIST_MAX) /* * Reject flags, only allow namespaces. -- 1.7.12.2.21.g234cd45.dirty