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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0705EC001DE for ; Mon, 24 Jul 2023 01:22:09 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1C0A810E240; Mon, 24 Jul 2023 01:22:08 +0000 (UTC) Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by gabe.freedesktop.org (Postfix) with ESMTPS id 76E4010E240 for ; Mon, 24 Jul 2023 01:22:06 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id F161660E9C; Mon, 24 Jul 2023 01:22:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 052F6C433CC; Mon, 24 Jul 2023 01:22:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690161725; bh=QhZf8toMd5+zDGE1EOIeW6wBNB1VaLLB+7VguP4KCAE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XZd/+hzLzDmDDgdgDlolWa/N65EciP5nslL1pyAlrasFVTWcW74iS8kckewop+c08 O4ebMkurCQsmsjf0tRWKN/lbUTaOFi/flT2sX6zWmVvrKEL5Lvzy61hHoneO6IQA/N K5dROOZWtrOyb4GPrDdOr+WacWZyfEHX0DKeUhXkMwdrvjQXmshZNo6tmg8trgslQg YJfy2O8pROebtUmuW2IlYwyiic86cPm2g9rEwi53gZ1Pj+gT3DUS00vXke+E2xPdAD tqqzdVcnqarYDykuo3VnD1pipKfjd8rMBdQ/bvb5Y5nVl2bcteGKy68yeNUh9uBxqr AOftbQK1dazmA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 6.1 11/41] drm/stm: ltdc: fix late dereference check Date: Sun, 23 Jul 2023 21:20:44 -0400 Message-Id: <20230724012118.2316073-11-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230724012118.2316073-1-sashal@kernel.org> References: <20230724012118.2316073-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.1.40 Content-Transfer-Encoding: 8bit X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Sasha Levin , mcoquelin.stm32@gmail.com, Dan Carpenter , Raphael Gallais-Pou , yannick.fertre@foss.st.com, alexandre.torgue@foss.st.com, dri-devel@lists.freedesktop.org, Philippe Cornu , linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, kernel test robot Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Raphael Gallais-Pou [ Upstream commit 898a9e3f56db9860ab091d4bf41b6caa99aafc3d ] In ltdc_crtc_set_crc_source(), struct drm_crtc was dereferenced in a container_of() before the pointer check. This could cause a kernel panic. Fix this smatch warning: drivers/gpu/drm/stm/ltdc.c:1124 ltdc_crtc_set_crc_source() warn: variable dereferenced before check 'crtc' (see line 1119) Reported-by: kernel test robot Closes: https://lore.kernel.org/lkml/202212241802.zeLFZCXB-lkp@intel.com/ Reported-by: Dan Carpenter Closes: https://lore.kernel.org/lkml/202212241802.zeLFZCXB-lkp@intel.com/ Signed-off-by: Raphael Gallais-Pou Acked-by: Philippe Cornu Signed-off-by: Philippe Cornu Link: https://patchwork.freedesktop.org/patch/msgid/20230515123818.93971-1-raphael.gallais-pou@foss.st.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/stm/ltdc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c index 03c6becda795c..b8be4c1db4235 100644 --- a/drivers/gpu/drm/stm/ltdc.c +++ b/drivers/gpu/drm/stm/ltdc.c @@ -1145,7 +1145,7 @@ static void ltdc_crtc_disable_vblank(struct drm_crtc *crtc) static int ltdc_crtc_set_crc_source(struct drm_crtc *crtc, const char *source) { - struct ltdc_device *ldev = crtc_to_ltdc(crtc); + struct ltdc_device *ldev; int ret; DRM_DEBUG_DRIVER("\n"); @@ -1153,6 +1153,8 @@ static int ltdc_crtc_set_crc_source(struct drm_crtc *crtc, const char *source) if (!crtc) return -ENODEV; + ldev = crtc_to_ltdc(crtc); + if (source && strcmp(source, "auto") == 0) { ldev->crc_active = true; ret = regmap_set_bits(ldev->regmap, LTDC_GCR, GCR_CRCEN); -- 2.39.2