From patchwork Thu Jun 26 17:23:55 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Harrison X-Patchwork-Id: 4428991 Return-Path: X-Original-To: patchwork-intel-gfx@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 365A6BEEAA for ; Thu, 26 Jun 2014 17:25:38 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4E8BC20304 for ; Thu, 26 Jun 2014 17:25:36 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 712C520381 for ; Thu, 26 Jun 2014 17:25:31 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 58DDC6E226; Thu, 26 Jun 2014 10:25:27 -0700 (PDT) X-Original-To: Intel-GFX@lists.freedesktop.org Delivered-To: Intel-GFX@lists.freedesktop.org Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTP id 7ED2B6E1C2 for ; Thu, 26 Jun 2014 10:25:25 -0700 (PDT) Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga102.fm.intel.com with ESMTP; 26 Jun 2014 10:25:25 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.01,554,1400050800"; d="scan'208";a="561434532" Received: from johnharr-linux.iwi.intel.com ([172.28.253.52]) by fmsmga002.fm.intel.com with ESMTP; 26 Jun 2014 10:24:59 -0700 From: John.C.Harrison@Intel.com To: Intel-GFX@lists.freedesktop.org Date: Thu, 26 Jun 2014 18:23:55 +0100 Message-Id: <1403803475-16337-5-git-send-email-John.C.Harrison@Intel.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1403803475-16337-1-git-send-email-John.C.Harrison@Intel.com> References: <1403803475-16337-1-git-send-email-John.C.Harrison@Intel.com> Organization: Intel Corporation (UK) Ltd. - Co. Reg. #1134945 - Pipers Way, Swindon SN3 1RJ Subject: [Intel-gfx] [RFC 04/44] drm/i915: Fix null pointer dereference in error capture X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: John Harrison The i915_gem_record_rings() code was unconditionally querying and saving state for the batch_obj of a request structure. This is not necessarily set. Thus a null pointer dereference can occur. Reviewed-by: Jesse Barnes --- drivers/gpu/drm/i915/i915_gpu_error.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c index 87ec60e..0738f21 100644 --- a/drivers/gpu/drm/i915/i915_gpu_error.c +++ b/drivers/gpu/drm/i915/i915_gpu_error.c @@ -902,12 +902,13 @@ static void i915_gem_record_rings(struct drm_device *dev, * as the simplest method to avoid being overwritten * by userspace. */ - error->ring[i].batchbuffer = - i915_error_object_create(dev_priv, - request->batch_obj, - request->ctx ? - request->ctx->vm : - &dev_priv->gtt.base); + if(request->batch_obj) + error->ring[i].batchbuffer = + i915_error_object_create(dev_priv, + request->batch_obj, + request->ctx ? + request->ctx->vm : + &dev_priv->gtt.base); if (HAS_BROKEN_CS_TLB(dev_priv->dev) && ring->scratch.obj)