From patchwork Mon Dec 28 12:46:05 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 354739 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=-18.8 required=3.0 tests=BAYES_00,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 D04B8C433E0 for ; Mon, 28 Dec 2020 14:56:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9768722AEC for ; Mon, 28 Dec 2020 14:56:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2408097AbgL1Ozu (ORCPT ); Mon, 28 Dec 2020 09:55:50 -0500 Received: from mail.kernel.org ([198.145.29.99]:52136 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2441219AbgL1ORB (ORCPT ); Mon, 28 Dec 2020 09:17:01 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id C283022AAA; Mon, 28 Dec 2020 14:16:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1609164980; bh=hBwo5UXRJC0YzTAz3HQDeIVycszqgjZdqb20HN6tMYc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q5fKjzN3NuTuQsa5bWbLWTioYy/8T+gWXinw1Awio7VjIxzGPaDGKoUJfLKGiUXIm GWaFa3O7djSX353o2IhlnF+k7hnXYnmxGHPaR7VNrM0ivCpelXXI6BnUaY2bj0N+91 MRfXWY5XCgeNfo8+4JGv92Ss2YLBPHV4/xpOzJZo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Colin Ian King , Vinod Koul , Sasha Levin Subject: [PATCH 5.10 367/717] drm/mediatek: avoid dereferencing a null hdmi_phy on an error message Date: Mon, 28 Dec 2020 13:46:05 +0100 Message-Id: <20201228125038.589605736@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201228125020.963311703@linuxfoundation.org> References: <20201228125020.963311703@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Colin Ian King [ Upstream commit b097efba9580d1f7cbc80cda84e768983e3de541 ] Currently there is a null pointer check for hdmi_phy that implies it may be null, however a dev_err messages dereferences this potential null pointer. Avoid a null pointer dereference by only emitting the dev_err message if hdmi_phy is non-null. It is a moot point if the error message needs to be printed at all, but since this is a relatively new piece of code it may be useful to keep the message in for the moment in case there are unforseen errors that need to be reported. Fixes: be28b6507c46 ("drm/mediatek: separate hdmi phy to different file") Signed-off-by: Colin Ian King Addresses-Coverity: ("Dereference after null check") Link: https://lore.kernel.org/r/20201207150937.170435-1-colin.king@canonical.com [vkoul: fix indent of return call] Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/phy/mediatek/phy-mtk-hdmi.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/phy/mediatek/phy-mtk-hdmi.c b/drivers/phy/mediatek/phy-mtk-hdmi.c index 47c029d4b270b..206cc34687223 100644 --- a/drivers/phy/mediatek/phy-mtk-hdmi.c +++ b/drivers/phy/mediatek/phy-mtk-hdmi.c @@ -84,8 +84,9 @@ mtk_hdmi_phy_dev_get_ops(const struct mtk_hdmi_phy *hdmi_phy) hdmi_phy->conf->hdmi_phy_disable_tmds) return &mtk_hdmi_phy_dev_ops; - dev_err(hdmi_phy->dev, "Failed to get dev ops of phy\n"); - return NULL; + if (hdmi_phy) + dev_err(hdmi_phy->dev, "Failed to get dev ops of phy\n"); + return NULL; } static void mtk_hdmi_phy_clk_get_data(struct mtk_hdmi_phy *hdmi_phy,