From patchwork Tue Apr 5 07:20:13 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 558082 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DFC3AC433EF for ; Tue, 5 Apr 2022 08:19:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233810AbiDEILH (ORCPT ); Tue, 5 Apr 2022 04:11:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36474 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232875AbiDEIEV (ORCPT ); Tue, 5 Apr 2022 04:04:21 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA57858E52; Tue, 5 Apr 2022 01:01:01 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 545C7B81B18; Tue, 5 Apr 2022 08:01:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C25DDC340EE; Tue, 5 Apr 2022 08:00:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649145659; bh=5I/RLfgBX6c5mspTVHVaPkGuMGxNuOsnnKaZo+oTV0o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NxxyCYxWuQ/1+cYTrsgMTeH/GDbWtf28mE5MvuVgRCSWZ1XaVhYiibTwxpCOhKM6H 0JAJzsObrb5gdqocBFlXDDDbGdM4PZc+H6sHeScTRUSJUhqSqIA54AFg0Gwq88z0O4 Ypl8o4feMUmcaMz1bE+6+lMQW7PTWsY+hL8A3xEw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Zhou Qingyang , Alex Deucher , Sasha Levin Subject: [PATCH 5.17 0466/1126] drm/amd/display: Fix a NULL pointer dereference in amdgpu_dm_connector_add_common_modes() Date: Tue, 5 Apr 2022 09:20:13 +0200 Message-Id: <20220405070421.306046036@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220405070407.513532867@linuxfoundation.org> References: <20220405070407.513532867@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Zhou Qingyang [ Upstream commit 588a70177df3b1777484267584ef38ab2ca899a2 ] In amdgpu_dm_connector_add_common_modes(), amdgpu_dm_create_common_mode() is assigned to mode and is passed to drm_mode_probed_add() directly after that. drm_mode_probed_add() passes &mode->head to list_add_tail(), and there is a dereference of it in list_add_tail() without recoveries, which could lead to NULL pointer dereference on failure of amdgpu_dm_create_common_mode(). Fix this by adding a NULL check of mode. This bug was found by a static analyzer. Builds with 'make allyesconfig' show no new warnings, and our static analyzer no longer warns about this code. Fixes: e7b07ceef2a6 ("drm/amd/display: Merge amdgpu_dm_types and amdgpu_dm") Signed-off-by: Zhou Qingyang Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index 075429bea427..5f4a346c9c2a 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -8144,6 +8144,9 @@ static void amdgpu_dm_connector_add_common_modes(struct drm_encoder *encoder, mode = amdgpu_dm_create_common_mode(encoder, common_modes[i].name, common_modes[i].w, common_modes[i].h); + if (!mode) + continue; + drm_mode_probed_add(connector, mode); amdgpu_dm_connector->num_modes++; }