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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DD0ACC001E0 for ; Mon, 24 Jul 2023 01:16:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229962AbjGXBQa (ORCPT ); Sun, 23 Jul 2023 21:16:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46506 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230078AbjGXBQN (ORCPT ); Sun, 23 Jul 2023 21:16:13 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1B5961722; Sun, 23 Jul 2023 18:15:55 -0700 (PDT) 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 D472060F04; Mon, 24 Jul 2023 01:15:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D99C7C433C7; Mon, 24 Jul 2023 01:14:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690161300; bh=QhZf8toMd5+zDGE1EOIeW6wBNB1VaLLB+7VguP4KCAE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OUhAWf0eKyCot2e+mbFe1KQ9YFR0jcjjhPaYFrokV/ojDoCmwWqPeCUSc23cx3kLg UuTj44IuTrAuCyTSajBHo2A4gHYplr6Lvb8UPqKaFj9MIF4Zc5I33ToX+8jVI+mtMx 1g+fv93Kz+un6oZV2Zs23SpMDvqpWBKH+/LQ48aNmTesMghmXVoZVNKAJnkJ2w99o/ BM8e2HkJpd/p5S+MwivnFg2S5qkDhj8xkZF/24T2NqR+iVXc2/mHXF1+cVhvWeyNf0 fzo6Iwce6B4T3FCG+bfFwX+9CxhdTc+kFab1QBVVDh+vXl2pAQ3UrCqkGz3W/b4PR9 8dxAlY8RchzgQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Raphael Gallais-Pou , kernel test robot , Dan Carpenter , Philippe Cornu , Sasha Levin , yannick.fertre@foss.st.com, airlied@gmail.com, daniel@ffwll.ch, mcoquelin.stm32@gmail.com, alexandre.torgue@foss.st.com, dri-devel@lists.freedesktop.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org Subject: [PATCH AUTOSEL 6.4 16/58] drm/stm: ltdc: fix late dereference check Date: Sun, 23 Jul 2023 21:12:44 -0400 Message-Id: <20230724011338.2298062-16-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230724011338.2298062-1-sashal@kernel.org> References: <20230724011338.2298062-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.4.5 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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