From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753964AbdDJRwV (ORCPT ); Mon, 10 Apr 2017 13:52:21 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:34518 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752526AbdDJQob (ORCPT ); Mon, 10 Apr 2017 12:44:31 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Murray McAllister , Sinclair Yeh Subject: [PATCH 4.9 004/152] drm/vmwgfx: NULL pointer dereference in vmw_surface_define_ioctl() Date: Mon, 10 Apr 2017 18:40:56 +0200 Message-Id: <20170410164200.156567826@linuxfoundation.org> X-Mailer: git-send-email 2.12.2 In-Reply-To: <20170410164159.934755016@linuxfoundation.org> References: <20170410164159.934755016@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Murray McAllister commit 36274ab8c596f1240c606bb514da329add2a1bcd upstream. Before memory allocations vmw_surface_define_ioctl() checks the upper-bounds of a user-supplied size, but does not check if the supplied size is 0. Add check to avoid NULL pointer dereferences. Signed-off-by: Murray McAllister Reviewed-by: Sinclair Yeh Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/vmwgfx/vmwgfx_surface.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c @@ -716,8 +716,8 @@ int vmw_surface_define_ioctl(struct drm_ for (i = 0; i < DRM_VMW_MAX_SURFACE_FACES; ++i) num_sizes += req->mip_levels[i]; - if (num_sizes > DRM_VMW_MAX_SURFACE_FACES * - DRM_VMW_MAX_MIP_LEVELS) + if (num_sizes > DRM_VMW_MAX_SURFACE_FACES * DRM_VMW_MAX_MIP_LEVELS || + num_sizes == 0) return -EINVAL; size = vmw_user_surface_size + 128 +