From patchwork Mon Jun 25 12:18:44 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gustavo A. R. Silva" X-Patchwork-Id: 10488163 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4E1E5601A0 for ; Tue, 26 Jun 2018 07:27:19 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 34DB22874C for ; Tue, 26 Jun 2018 07:27:19 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2998B28787; Tue, 26 Jun 2018 07:27:19 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id C190A2874C for ; Tue, 26 Jun 2018 07:27:18 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id CAB696E462; Tue, 26 Jun 2018 07:24:27 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org X-Greylist: delayed 1275 seconds by postgrey-1.36 at gabe; Mon, 25 Jun 2018 12:47:52 UTC Received: from gateway31.websitewelcome.com (gateway31.websitewelcome.com [192.185.143.40]) by gabe.freedesktop.org (Postfix) with ESMTPS id F38496E1BE for ; Mon, 25 Jun 2018 12:47:52 +0000 (UTC) Received: from cm12.websitewelcome.com (cm12.websitewelcome.com [100.42.49.8]) by gateway31.websitewelcome.com (Postfix) with ESMTP id 99D05A9D71 for ; Mon, 25 Jun 2018 07:18:47 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id XQSFfaYRESjJAXQSFf77ND; 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 Subject: [PATCH] drm/gma500: Fix potential NULL pointer dereference Message-ID: <20180625121844.GA12466@embeddedor.com> MIME-Version: 1.0 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 - lists.freedesktop.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: 3 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes X-Mailman-Approved-At: Tue, 26 Jun 2018 07:24:15 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, "Gustavo A. R. Silva" Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP 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);