From patchwork Mon Mar 19 19:30:53 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: 10302439 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 D243960349 for ; Thu, 22 Mar 2018 22:06:36 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BAE30287E9 for ; Thu, 22 Mar 2018 22:06:36 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AF2DE28A0C; Thu, 22 Mar 2018 22:06:36 +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=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=unavailable 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 BDD80287E9 for ; Thu, 22 Mar 2018 22:06:35 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id DA1C16E116; Thu, 22 Mar 2018 22:05:24 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org X-Greylist: delayed 1341 seconds by postgrey-1.36 at gabe; Mon, 19 Mar 2018 19:53:18 UTC Received: from gateway24.websitewelcome.com (gateway24.websitewelcome.com [192.185.51.251]) by gabe.freedesktop.org (Postfix) with ESMTPS id F2D6189F61 for ; Mon, 19 Mar 2018 19:53:18 +0000 (UTC) Received: from cm13.websitewelcome.com (cm13.websitewelcome.com [100.42.49.6]) by gateway24.websitewelcome.com (Postfix) with ESMTP id D6BD82F59B for ; Mon, 19 Mar 2018 14:30:56 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id y0Uhei4wuQUwqy0UheZQDQ; Mon, 19 Mar 2018 14:30:56 -0500 Received: from [189.145.36.34] (port=37902 helo=embeddedgus) by gator4166.hostgator.com with esmtpa (Exim 4.89_1) (envelope-from ) id 1ey0Uh-0041gY-6N; Mon, 19 Mar 2018 14:30:55 -0500 Date: Mon, 19 Mar 2018 14:30:53 -0500 From: "Gustavo A. R. Silva" To: Zhenyu Wang , Zhi Wang , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , David Airlie Subject: [PATCH] drm/i915/gvt/scheduler: fix potential NULL pointer dereference Message-ID: <20180319193053.GA7016@embeddedgus> 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: 189.145.36.34 X-Source-L: No X-Exim-ID: 1ey0Uh-0041gY-6N X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedgus) [189.145.36.34]:37902 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 9 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes X-Mailman-Approved-At: Thu, 22 Mar 2018 22:05:16 +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: intel-gfx@lists.freedesktop.org, intel-gvt-dev@lists.freedesktop.org, 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 _workload_ is being dereferenced before it is null checked, hence there is a potential null pointer dereference. Fix this by moving the pointer dereference after _workload_ has been null checked. Addresses-Coverity-ID: 1430136 ("Dereference before null check") Fixes: fa3dd623e559 ("drm/i915/gvt: keep oa config in shadow ctx") Signed-off-by: Gustavo A. R. Silva --- drivers/gpu/drm/i915/gvt/scheduler.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/gvt/scheduler.c b/drivers/gpu/drm/i915/gvt/scheduler.c index 0681264..be1a297 100644 --- a/drivers/gpu/drm/i915/gvt/scheduler.c +++ b/drivers/gpu/drm/i915/gvt/scheduler.c @@ -60,9 +60,9 @@ static void set_context_pdp_root_pointer( static void sr_oa_regs(struct intel_vgpu_workload *workload, u32 *reg_state, bool save) { - struct drm_i915_private *dev_priv = workload->vgpu->gvt->dev_priv; - u32 ctx_oactxctrl = dev_priv->perf.oa.ctx_oactxctrl_offset; - u32 ctx_flexeu0 = dev_priv->perf.oa.ctx_flexeu0_offset; + struct drm_i915_private *dev_priv; + u32 ctx_oactxctrl; + u32 ctx_flexeu0; int i = 0; u32 flex_mmio[] = { i915_mmio_reg_offset(EU_PERF_CNTL0), @@ -77,6 +77,10 @@ static void sr_oa_regs(struct intel_vgpu_workload *workload, if (!workload || !reg_state || workload->ring_id != RCS) return; + dev_priv = workload->vgpu->gvt->dev_priv; + ctx_oactxctrl = dev_priv->perf.oa.ctx_oactxctrl_offset; + ctx_flexeu0 = dev_priv->perf.oa.ctx_flexeu0_offset; + if (save) { workload->oactxctrl = reg_state[ctx_oactxctrl + 1];