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 3191CC433F5 for ; Mon, 7 Mar 2022 09:43:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238016AbiCGJoj (ORCPT ); Mon, 7 Mar 2022 04:44:39 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241149AbiCGJl4 (ORCPT ); Mon, 7 Mar 2022 04:41:56 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8BAC96252; Mon, 7 Mar 2022 01:40:50 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2B73E611D5; Mon, 7 Mar 2022 09:40:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 33BCDC340F3; Mon, 7 Mar 2022 09:40:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1646646049; bh=Lc8jc0mvjGKkI5mWqYol9JlaBHGpE0J/ZnEnk/UGLYI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DoKQpEghJ5iLiZtg8DzsvbZq3XaQ/RcawjIolPv13VTJk8sJQhpBZQikjaNU45IQH 3b9RJzSFcHiyhcclPk2S6DqUg9+0+CoyQ5jO8eKYg4X5W9K5GuLxZ3lkCv3VZJO/ZM C6FfSwUrK9a1/d3RFxJMxCQa0BxvYMBVVdsmrHDA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alexander Stein , Marek Vasut , Sasha Levin Subject: [PATCH 5.15 116/262] drm: mxsfb: Fix NULL pointer dereference Date: Mon, 7 Mar 2022 10:17:40 +0100 Message-Id: <20220307091705.741630517@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220307091702.378509770@linuxfoundation.org> References: <20220307091702.378509770@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: stable@vger.kernel.org From: Alexander Stein [ Upstream commit 622c9a3a7868e1eeca39c55305ca3ebec4742b64 ] mxsfb should not ever dereference the NULL pointer which drm_atomic_get_new_bridge_state is allowed to return. Assume a fixed format instead. Fixes: b776b0f00f24 ("drm: mxsfb: Use bus_format from the nearest bridge if present") Signed-off-by: Alexander Stein Signed-off-by: Marek Vasut Link: https://patchwork.freedesktop.org/patch/msgid/20220202081755.145716-3-alexander.stein@ew.tq-group.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/mxsfb/mxsfb_kms.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/mxsfb/mxsfb_kms.c b/drivers/gpu/drm/mxsfb/mxsfb_kms.c index b96ba348c68d9..988bc4fbd78df 100644 --- a/drivers/gpu/drm/mxsfb/mxsfb_kms.c +++ b/drivers/gpu/drm/mxsfb/mxsfb_kms.c @@ -361,7 +361,11 @@ static void mxsfb_crtc_atomic_enable(struct drm_crtc *crtc, bridge_state = drm_atomic_get_new_bridge_state(state, mxsfb->bridge); - bus_format = bridge_state->input_bus_cfg.format; + if (!bridge_state) + bus_format = MEDIA_BUS_FMT_FIXED; + else + bus_format = bridge_state->input_bus_cfg.format; + if (bus_format == MEDIA_BUS_FMT_FIXED) { dev_warn_once(drm->dev, "Bridge does not provide bus format, assuming MEDIA_BUS_FMT_RGB888_1X24.\n" -- 2.34.1