From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932908Ab2EDVAg (ORCPT ); Fri, 4 May 2012 17:00:36 -0400 Received: from mail-pz0-f45.google.com ([209.85.210.45]:45099 "EHLO mail-pz0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932815Ab2EDUsh (ORCPT ); Fri, 4 May 2012 16:48:37 -0400 Message-Id: <20120504204246.091942865@linuxfoundation.org> User-Agent: quilt/0.60-19.1 Date: Fri, 04 May 2012 13:42:58 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Xi Wang , Chris Wilson , Daniel Vetter Subject: [ 14/47] drm/i915: fix integer overflow in i915_gem_do_execbuffer() In-Reply-To: <20120504204307.GA13761@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Xi Wang commit 44afb3a04391a74309d16180d1e4f8386fdfa745 upstream. On 32-bit systems, a large args->num_cliprects from userspace via ioctl may overflow the allocation size, leading to out-of-bounds access. This vulnerability was introduced in commit 432e58ed ("drm/i915: Avoid allocation for execbuffer object list"). Signed-off-by: Xi Wang Reviewed-by: Chris Wilson Signed-off-by: Daniel Vetter Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/i915_gem_execbuffer.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c +++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c @@ -1046,6 +1046,11 @@ i915_gem_do_execbuffer(struct drm_device return -EINVAL; } + if (args->num_cliprects > UINT_MAX / sizeof(*cliprects)) { + DRM_DEBUG("execbuf with %u cliprects\n", + args->num_cliprects); + return -EINVAL; + } cliprects = kmalloc(args->num_cliprects * sizeof(*cliprects), GFP_KERNEL); if (cliprects == NULL) {