Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754513AbdLFJNC (ORCPT ); Wed, 6 Dec 2017 04:13:02 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:45122 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754103AbdLFJM5 (ORCPT ); Wed, 6 Dec 2017 04:12:57 -0500 X-Google-Smtp-Source: AGs4zMYFDLrdvYLBY2yv0mZR0JjtcxJ9dF0Yks5d24WH7uzGA8IIXu8rzwOyWm8pUqi+Q6N/jU6MZQ== Date: Wed, 6 Dec 2017 10:12:54 +0100 From: Daniel Vetter To: "Gustavo A. R. Silva" Cc: Daniel Vetter , Jani Nikula , Gustavo Padovan , Sean Paul , David Airlie , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [PATCH] drm/fb-helper: Fix potential NULL pointer dereference Message-ID: <20171206091254.cwc3jxwvt27fd5gu@phenom.ffwll.local> Mail-Followup-To: "Gustavo A. R. Silva" , Daniel Vetter , Jani Nikula , Gustavo Padovan , Sean Paul , David Airlie , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org References: <20171205174628.GA31189@embeddedor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171205174628.GA31189@embeddedor.com> X-Operating-System: Linux phenom 4.13.0-1-amd64 User-Agent: NeoMutt/20170609 (1.8.3) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1765 Lines: 53 On Tue, Dec 05, 2017 at 11:46:28AM -0600, Gustavo A. R. Silva wrote: > fb_helper 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_helper > has been null checked. > > This issue was detected with the help of Coccinelle. > > Fixes: c777990fb45b ("drm/fb-helper: Handle function NULL argument") > Signed-off-by: Gustavo A. R. Silva Oops. Applied to drm-misc-next, thanks for your patch. -Daniel > --- > drivers/gpu/drm/drm_fb_helper.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c > index 6654f2f..04a3a5c 100644 > --- a/drivers/gpu/drm/drm_fb_helper.c > +++ b/drivers/gpu/drm/drm_fb_helper.c > @@ -178,7 +178,7 @@ EXPORT_SYMBOL(drm_fb_helper_add_one_connector); > */ > int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper) > { > - struct drm_device *dev = fb_helper->dev; > + struct drm_device *dev; > struct drm_connector *connector; > struct drm_connector_list_iter conn_iter; > int i, ret = 0; > @@ -186,6 +186,8 @@ int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper) > if (!drm_fbdev_emulation || !fb_helper) > return 0; > > + dev = fb_helper->dev; > + > mutex_lock(&fb_helper->lock); > drm_connector_list_iter_begin(dev, &conn_iter); > drm_for_each_connector_iter(connector, &conn_iter) { > -- > 2.7.4 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch