From patchwork Thu Sep 16 16:00:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "gregkh@linuxfoundation.org" X-Patchwork-Id: 513655 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=-19.1 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=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 C71BFC433F5 for ; Thu, 16 Sep 2021 17:34:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B54966023D for ; Thu, 16 Sep 2021 17:34:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347601AbhIPRgQ (ORCPT ); Thu, 16 Sep 2021 13:36:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:50298 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348503AbhIPRc3 (ORCPT ); Thu, 16 Sep 2021 13:32:29 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0F6B063215; Thu, 16 Sep 2021 16:47:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1631810868; bh=5LuBohqvQBhRmRYfLetL1XDC8lNwVpB96plU8EyjnMM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Jo7ayBZmvqp7rDm9CadW3/YMpSmApOBOn5oiqWyYlY4XY+RG+xG+HoxMAjPlFdnNv i2taDQlkZ+SgK8p8Ri/9+XaMALPe1GykmT+QPE6xTwzbqmBWR7V2qMMZZc/7+bYPav GHmBHfv99e793aZVlz3/xpbFQ87uKGNz601tmSew= 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 5.14 296/432] drm/display: fix possible null-pointer dereference in dcn10_set_clock() Date: Thu, 16 Sep 2021 18:00:45 +0200 Message-Id: <20210916155820.863945105@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210916155810.813340753@linuxfoundation.org> References: <20210916155810.813340753@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 dee1ce5f9609..75fa4adcf5f4 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 @@ -3628,13 +3628,12 @@ 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; @@ -3652,7 +3651,7 @@ 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;