From patchwork Sun Jul 8 11:37:41 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julia Lawall X-Patchwork-Id: 1169731 Return-Path: X-Original-To: patchwork-dri-devel@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by patchwork1.kernel.org (Postfix) with ESMTP id 7A2D240134 for ; Sun, 8 Jul 2012 15:39:31 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3DB619EB47 for ; Sun, 8 Jul 2012 08:34:31 -0700 (PDT) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail1-relais-roc.national.inria.fr (mail1-relais-roc.national.inria.fr [192.134.164.82]) by gabe.freedesktop.org (Postfix) with ESMTP id 8B0BB9E808 for ; Sun, 8 Jul 2012 04:37:50 -0700 (PDT) X-IronPort-AV: E=Sophos;i="4.77,546,1336341600"; d="scan'208";a="166023139" Received: from palace.lip6.fr (HELO localhost.localdomain) ([132.227.105.202]) by mail1-relais-roc.national.inria.fr with ESMTP/TLS/DHE-RSA-AES256-SHA; 08 Jul 2012 13:37:47 +0200 From: Julia Lawall To: David Airlie Subject: [PATCH 4/7] drivers/gpu/drm: remove invalid reference to list iterator variable Date: Sun, 8 Jul 2012 13:37:41 +0200 Message-Id: <1341747464-1772-5-git-send-email-Julia.Lawall@lip6.fr> X-Mailer: git-send-email 1.7.8.6 In-Reply-To: <1341747464-1772-1-git-send-email-Julia.Lawall@lip6.fr> References: <1341747464-1772-1-git-send-email-Julia.Lawall@lip6.fr> X-Mailman-Approved-At: Sun, 08 Jul 2012 08:33:29 -0700 Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: dri-devel-bounces+patchwork-dri-devel=patchwork.kernel.org@lists.freedesktop.org Errors-To: dri-devel-bounces+patchwork-dri-devel=patchwork.kernel.org@lists.freedesktop.org From: Julia Lawall If list_for_each_entry, etc complete a traversal of the list, the iterator variable ends up pointing to an address at an offset from the list head, and not a meaningful structure. Thus this value should not be used after the end of the iterator. In the first two cases, a a break is added after the switch; the break in the switch would jump out of the switch, but not out of the complete iteration. In the first case, the null test on connector is removed, because the iterator variable of list_for_each_entry is never null. In the third case, entry->base.crtc.fb is not a meaningful value. What seems to be intended is crtc->fb, which gets the information from the last element of the list. These problems were found using Coccinelle (http://coccinelle.lip6.fr/). Signed-off-by: Julia Lawall Acked-by: Paul Menzel --- drivers/gpu/drm/gma500/mdfld_intel_display.c | 4 +--- drivers/gpu/drm/gma500/oaktrail_crtc.c | 1 + drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c | 2 +- 3 files changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/gma500/mdfld_intel_display.c b/drivers/gpu/drm/gma500/mdfld_intel_display.c index 3f3cd61..fc1ced0 100644 --- a/drivers/gpu/drm/gma500/mdfld_intel_display.c +++ b/drivers/gpu/drm/gma500/mdfld_intel_display.c @@ -755,9 +755,6 @@ static int mdfld_crtc_mode_set(struct drm_crtc *crtc, sizeof(struct drm_display_mode)); list_for_each_entry(connector, &mode_config->connector_list, head) { - if (!connector) - continue; - encoder = connector->encoder; if (!encoder) @@ -779,6 +776,7 @@ static int mdfld_crtc_mode_set(struct drm_crtc *crtc, is_hdmi = true; break; } + break; } /* Disable the VGA plane that we never use */ diff --git a/drivers/gpu/drm/gma500/oaktrail_crtc.c b/drivers/gpu/drm/gma500/oaktrail_crtc.c index f821c83..4b2172e 100644 --- a/drivers/gpu/drm/gma500/oaktrail_crtc.c +++ b/drivers/gpu/drm/gma500/oaktrail_crtc.c @@ -329,6 +329,7 @@ static int oaktrail_crtc_mode_set(struct drm_crtc *crtc, is_mipi = true; break; } + break; } /* Disable the VGA plane that we never use */ diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c b/drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c index 070fb23..634611a 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c @@ -93,7 +93,7 @@ static int vmw_ldu_commit_list(struct vmw_private *dev_priv) if (crtc == NULL) return 0; - fb = entry->base.crtc.fb; + fb = crtc->fb; return vmw_kms_write_svga(dev_priv, w, h, fb->pitches[0], fb->bits_per_pixel, fb->depth);