From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DE668C43144 for ; Mon, 25 Jun 2018 12:18:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9550E22466 for ; Mon, 25 Jun 2018 12:18:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9550E22466 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=embeddedor.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933572AbeFYMSv (ORCPT ); Mon, 25 Jun 2018 08:18:51 -0400 Received: from gateway32.websitewelcome.com ([192.185.145.178]:38967 "EHLO gateway32.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933170AbeFYMSs (ORCPT ); Mon, 25 Jun 2018 08:18:48 -0400 Received: from cm12.websitewelcome.com (cm12.websitewelcome.com [100.42.49.8]) by gateway32.websitewelcome.com (Postfix) with ESMTP id 9A845244E430 for ; Mon, 25 Jun 2018 07:18:47 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id XQSFfaYRDSjJAXQSFf77NC; Mon, 25 Jun 2018 07:18:47 -0500 X-Authority-Reason: nr=8 Received: from [189.250.65.56] (port=55734 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1fXQSF-002agD-3D; Mon, 25 Jun 2018 07:18:47 -0500 Date: Mon, 25 Jun 2018 07:18:44 -0500 From: "Gustavo A. R. Silva" To: Patrik Jakobsson , David Airlie Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] drm/gma500: Fix potential NULL pointer dereference Message-ID: <20180625121844.GA12466@embeddedor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.24 (2015-08-30) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 189.250.65.56 X-Source-L: No X-Exim-ID: 1fXQSF-002agD-3D X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.65.56]:55734 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 4 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org fb is being dereferenced before it is null checked, hence there is a potential null pointer dereference. Fix this by moving the pointer dereference after fb has been properly null checked at line 74: if (!fb) Addresses-Coverity-ID: 1470169 ("Dereference before null check") Signed-off-by: Gustavo A. R. Silva --- drivers/gpu/drm/gma500/gma_display.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/gma500/gma_display.c b/drivers/gpu/drm/gma500/gma_display.c index c8f071c..f767579 100644 --- a/drivers/gpu/drm/gma500/gma_display.c +++ b/drivers/gpu/drm/gma500/gma_display.c @@ -60,7 +60,7 @@ int gma_pipe_set_base(struct drm_crtc *crtc, int x, int y, struct drm_psb_private *dev_priv = dev->dev_private; struct gma_crtc *gma_crtc = to_gma_crtc(crtc); struct drm_framebuffer *fb = crtc->primary->fb; - struct gtt_range *gtt = to_gtt_range(fb->obj[0]); + struct gtt_range *gtt; int pipe = gma_crtc->pipe; const struct psb_offset *map = &dev_priv->regmap[pipe]; unsigned long start, offset; @@ -76,6 +76,8 @@ int gma_pipe_set_base(struct drm_crtc *crtc, int x, int y, goto gma_pipe_cleaner; } + gtt = to_gtt_range(fb->obj[0]); + /* We are displaying this buffer, make sure it is actually loaded into the GTT */ ret = psb_gtt_pin(gtt); -- 2.7.4