From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753041AbdF0LNO (ORCPT ); Tue, 27 Jun 2017 07:13:14 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:34844 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752137AbdF0LMi (ORCPT ); Tue, 27 Jun 2017 07:12:38 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Sinclair Yeh" , "Vladis Dronov" Date: Tue, 27 Jun 2017 12:10:34 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 5/7] drm/vmwgfx: limit the number of mip levels in vmw_gb_surface_define_ioctl() In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.45-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Vladis Dronov commit ee9c4e681ec4f58e42a83cb0c22a0289ade1aacf upstream. The 'req->mip_levels' parameter in vmw_gb_surface_define_ioctl() is a user-controlled 'uint32_t' value which is used as a loop count limit. This can lead to a kernel lockup and DoS. Add check for 'req->mip_levels'. References: https://bugzilla.redhat.com/show_bug.cgi?id=1437431 Signed-off-by: Vladis Dronov Reviewed-by: Sinclair Yeh Signed-off-by: Ben Hutchings --- drivers/gpu/drm/vmwgfx/vmwgfx_surface.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c @@ -1251,6 +1251,9 @@ int vmw_gb_surface_define_ioctl(struct d const struct svga3d_surface_desc *desc; uint32_t backup_handle; + if (req->mip_levels > DRM_VMW_MAX_MIP_LEVELS) + return -EINVAL; + if (unlikely(vmw_user_surface_size == 0)) vmw_user_surface_size = ttm_round_pot(sizeof(*user_srf)) + 128;