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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,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 E6AF9C6778D for ; Wed, 12 Sep 2018 14:32:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 96AFF20880 for ; Wed, 12 Sep 2018 14:32:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 96AFF20880 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 S1727998AbeILThA (ORCPT ); Wed, 12 Sep 2018 15:37:00 -0400 Received: from gateway30.websitewelcome.com ([192.185.152.11]:16031 "EHLO gateway30.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727670AbeILThA (ORCPT ); Wed, 12 Sep 2018 15:37:00 -0400 Received: from cm10.websitewelcome.com (cm10.websitewelcome.com [100.42.49.4]) by gateway30.websitewelcome.com (Postfix) with ESMTP id 839534341 for ; Wed, 12 Sep 2018 09:32:13 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id 06BRgqw7MBcCX06BagHP7T; Wed, 12 Sep 2018 09:32:13 -0500 X-Authority-Reason: nr=8 Received: from [189.250.106.191] (port=46028 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1g06BQ-002trA-Mf; Wed, 12 Sep 2018 09:31:57 -0500 Date: Wed, 12 Sep 2018 09:31:53 -0500 From: "Gustavo A. R. Silva" To: Paulo Zanoni , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , David Airlie Cc: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] drm/i915/dp: fix shifting by a negative number of bits Message-ID: <20180912143153.GA27564@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: 189.250.106.191 X-Source-L: No X-Exim-ID: 1g06BQ-002trA-Mf X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.106.191]:46028 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 8 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 Function intel_port_to_tc() returns PORT_TC_NONE on error, which is a negative value -1. In case PORT_TC_NONE is returned, there is an undefined behavior when shifting by a negative number of bits in both DP_PHY_MODE_STATUS_NOT_SAFE and P_PHY_MODE_STATUS_COMPLETED macros. Fix this by adding sanity checks on intel_port_to_tc return value, before using macros DP_PHY_MODE_STATUS_NOT_SAFE and P_PHY_MODE_STATUS_COMPLETED. Addresses-Coverity-ID: 1473324 ("Bad bit shift operation") Addresses-Coverity-ID: 1473325 ("Bad bit shift operation") Fixes: 39d1e234e1e1 ("drm/i915/icl: implement the tc/legacy HPD {dis,}connect flows") Signed-off-by: Gustavo A. R. Silva --- drivers/gpu/drm/i915/intel_dp.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 436c22d..e34b7b1 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -4811,6 +4811,11 @@ static bool icl_tc_phy_connect(struct drm_i915_private *dev_priv, dig_port->tc_type != TC_PORT_TYPEC) return true; + if (tc_port < 0) { + DRM_DEBUG_KMS("Bad TC port %d\n", tc_port); + return false; + } + val = I915_READ(PORT_TX_DFLEXDPPMS); if (!(val & DP_PHY_MODE_STATUS_COMPLETED(tc_port))) { DRM_DEBUG_KMS("DP PHY for TC port %d not ready\n", tc_port); @@ -4857,6 +4862,10 @@ static void icl_tc_phy_disconnect(struct drm_i915_private *dev_priv, dig_port->tc_type != TC_PORT_TYPEC) return; + if (tc_port < 0) { + DRM_DEBUG_KMS("Bad TC port %d\n", tc_port); + return; + } /* * This function may be called many times in a row without an HPD event * in between, so try to avoid the write when we can. -- 2.7.4