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=-20.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 A2A15C41535 for ; Mon, 20 Sep 2021 18:14:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 807D161B4C for ; Mon, 20 Sep 2021 18:14:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377162AbhITSPY (ORCPT ); Mon, 20 Sep 2021 14:15:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:35752 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1359601AbhITSKF (ORCPT ); Mon, 20 Sep 2021 14:10:05 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id AFD296326D; Mon, 20 Sep 2021 17:19:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1632158382; bh=YnPxrhg1s49V4lWDuTNR+ipJ7ngFuFI9dD3b1ucm4Hk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HHanOQoOpAi77S2gQbChmzn6nIl+xCWVd1XGZTCujPOowLx9Uqk9U1sJ0aQRDIoTf fHpLisAC5Ikz+kWpBSM9RSXf/UDyNHjXCC9JdqpCreBatqM41ZH69h/b/bKZVNjTTh O+oSWlPt5xTK7svS8DCdOChlzgV7ui0k9lMhHdck= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, TOTE Robot , Tuo Li , Alex Deucher , Sasha Levin Subject: [PATCH 5.4 131/260] drm/display: fix possible null-pointer dereference in dcn10_set_clock() Date: Mon, 20 Sep 2021 18:42:29 +0200 Message-Id: <20210920163935.582450275@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210920163931.123590023@linuxfoundation.org> References: <20210920163931.123590023@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tuo Li [ Upstream commit 554594567b1fa3da74f88ec7b2dc83d000c58e98 ] The variable dc->clk_mgr is checked in: if (dc->clk_mgr && dc->clk_mgr->funcs->get_clock) This indicates dc->clk_mgr can be NULL. However, it is dereferenced in: if (!dc->clk_mgr->funcs->get_clock) To fix this null-pointer dereference, check dc->clk_mgr and the function pointer dc->clk_mgr->funcs->get_clock earlier, and return if one of them is NULL. Reported-by: TOTE Robot Signed-off-by: Tuo Li Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- .../gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c index 60123db7ba02..bc5ebea1abed 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c @@ -3264,13 +3264,12 @@ static enum dc_status dcn10_set_clock(struct dc *dc, struct dc_clock_config clock_cfg = {0}; struct dc_clocks *current_clocks = &context->bw_ctx.bw.dcn.clk; - if (dc->clk_mgr && dc->clk_mgr->funcs->get_clock) - dc->clk_mgr->funcs->get_clock(dc->clk_mgr, - context, clock_type, &clock_cfg); - - if (!dc->clk_mgr->funcs->get_clock) + if (!dc->clk_mgr || !dc->clk_mgr->funcs->get_clock) return DC_FAIL_UNSUPPORTED_1; + dc->clk_mgr->funcs->get_clock(dc->clk_mgr, + context, clock_type, &clock_cfg); + if (clk_khz > clock_cfg.max_clock_khz) return DC_FAIL_CLK_EXCEED_MAX; @@ -3288,7 +3287,7 @@ static enum dc_status dcn10_set_clock(struct dc *dc, else return DC_ERROR_UNEXPECTED; - if (dc->clk_mgr && dc->clk_mgr->funcs->update_clocks) + if (dc->clk_mgr->funcs->update_clocks) dc->clk_mgr->funcs->update_clocks(dc->clk_mgr, context, true); return DC_OK; -- 2.30.2