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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 3970FC3A5A6 for ; Thu, 19 Sep 2019 17:11:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EEE01214AF for ; Thu, 19 Sep 2019 17:11:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391892AbfISRLs (ORCPT ); Thu, 19 Sep 2019 13:11:48 -0400 Received: from mail.netline.ch ([148.251.143.178]:43747 "EHLO netline-mail3.netline.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389131AbfISRLr (ORCPT ); Thu, 19 Sep 2019 13:11:47 -0400 Received: from localhost (localhost [127.0.0.1]) by netline-mail3.netline.ch (Postfix) with ESMTP id 3ADAB2AA0FB; Thu, 19 Sep 2019 19:11:44 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at netline-mail3.netline.ch Received: from netline-mail3.netline.ch ([127.0.0.1]) by localhost (netline-mail3.netline.ch [127.0.0.1]) (amavisd-new, port 10024) with LMTP id x1F0UOtU4EPY; Thu, 19 Sep 2019 19:11:42 +0200 (CEST) Received: from thor (116.245.63.188.dynamic.wline.res.cust.swisscom.ch [188.63.245.116]) by netline-mail3.netline.ch (Postfix) with ESMTPSA id C1D592AA0C6; Thu, 19 Sep 2019 19:11:42 +0200 (CEST) Received: from localhost ([::1]) by thor with esmtp (Exim 4.92.2) (envelope-from ) id 1iAzy2-00041o-Fl; Thu, 19 Sep 2019 19:11:42 +0200 Subject: Re: [PATCH] drm/radeon: fix a potential NULL pointer dereference To: Allen Pais Cc: dri-devel@lists.freedesktop.org, airlied@linux.ie, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org References: <1568824282-4081-1-git-send-email-allen.pais@oracle.com> From: =?UTF-8?Q?Michel_D=c3=a4nzer?= Openpgp: preference=signencrypt Autocrypt: addr=michel@daenzer.net; prefer-encrypt=mutual; keydata= mQGiBDsehS8RBACbsIQEX31aYSIuEKxEnEX82ezMR8z3LG8ktv1KjyNErUX9Pt7AUC7W3W0b LUhu8Le8S2va6hi7GfSAifl0ih3k6Bv1Itzgnd+7ZmSrvCN8yGJaHNQfAevAuEboIb+MaVHo 9EMJj4ikOcRZCmQWw7evu/D9uQdtkCnRY9iJiAGxbwCguBHtpoGMxDOINCr5UU6qt+m4O+UD /355ohBBzzyh49lTj0kTFKr0Ozd20G2FbcqHgfFL1dc1MPyigej2gLga2osu2QY0ObvAGkOu WBi3LTY8Zs8uqFGDC4ZAwMPoFy3yzu3ne6T7d/68rJil0QcdQjzzHi6ekqHuhst4a+/+D23h Za8MJBEcdOhRhsaDVGAJSFEQB1qLBACOs0xN+XblejO35gsDSVVk8s+FUUw3TSWJBfZa3Imp V2U2tBO4qck+wqbHNfdnU/crrsHahjzBjvk8Up7VoY8oT+z03sal2vXEonS279xN2B92Tttr AgwosujguFO/7tvzymWC76rDEwue8TsADE11ErjwaBTs8ZXfnN/uAANgPLQjTWljaGVsIERh ZW56ZXIgPG1pY2hlbEBkYWVuemVyLm5ldD6IXgQTEQIAHgUCQFXxJgIbAwYLCQgHAwIDFQID AxYCAQIeAQIXgAAKCRBaga+OatuyAIrPAJ9ykonXI3oQcX83N2qzCEStLNW47gCeLWm/QiPY jqtGUnnSbyuTQfIySkK5AQ0EOx6FRRAEAJZkcvklPwJCgNiw37p0GShKmFGGqf/a3xZZEpjI qNxzshFRFneZze4f5LhzbX1/vIm5+ZXsEWympJfZzyCmYPw86QcFxyZflkAxHx9LeD+89Elx bw6wT0CcLvSv8ROfU1m8YhGbV6g2zWyLD0/naQGVb8e4FhVKGNY2EEbHgFBrAAMGA/0VktFO CxFBdzLQ17RCTwCJ3xpyP4qsLJH0yCoA26rH2zE2RzByhrTFTYZzbFEid3ddGiHOBEL+bO+2 GNtfiYKmbTkj1tMZJ8L6huKONaVrASFzLvZa2dlc2zja9ZSksKmge5BOTKWgbyepEc5qxSju YsYrX5xfLgTZC5abhhztpYhGBBgRAgAGBQI7HoVFAAoJEFqBr45q27IAlscAn2Ufk2d6/3p4 Cuyz/NX7KpL2dQ8WAJ9UD5JEakhfofed8PSqOM7jOO3LCA== Message-ID: <5603dddb-8ae3-e145-69af-c6ccea68ca1b@daenzer.net> Date: Thu, 19 Sep 2019 19:11:42 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <1568824282-4081-1-git-send-email-allen.pais@oracle.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-CA Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019-09-18 6:31 p.m., Allen Pais wrote: > alloc_workqueue is not checked for errors and as a result, > a potential NULL dereference could occur. > > Signed-off-by: Allen Pais > --- > drivers/gpu/drm/radeon/radeon_display.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c > index bd52f15..1a41764 100644 > --- a/drivers/gpu/drm/radeon/radeon_display.c > +++ b/drivers/gpu/drm/radeon/radeon_display.c > @@ -683,6 +683,10 @@ static void radeon_crtc_init(struct drm_device *dev, int index) > drm_mode_crtc_set_gamma_size(&radeon_crtc->base, 256); > radeon_crtc->crtc_id = index; > radeon_crtc->flip_queue = alloc_workqueue("radeon-crtc", WQ_HIGHPRI, 0); > + if (unlikely(!radeon_crtc->flip_queue)) { > + kfree(radeon_crtc); > + return; > + } > rdev->mode_info.crtcs[index] = radeon_crtc; > > if (rdev->family >= CHIP_BONAIRE) { > I'm afraid just silently leaving the CRTC uninitialized isn't a good way to handle this. The failure would need to be propagated, probably resulting in the driver aborting its initialization altogether. -- Earthling Michel Dänzer | https://redhat.com Libre software enthusiast | Mesa and X developer