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 95A27C433EF for ; Tue, 7 Jun 2022 17:34:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347285AbiFGRef (ORCPT ); Tue, 7 Jun 2022 13:34:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45444 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346918AbiFGRZe (ORCPT ); Tue, 7 Jun 2022 13:25:34 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 65F50110AF2; Tue, 7 Jun 2022 10:23:39 -0700 (PDT) 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 ams.source.kernel.org (Postfix) with ESMTPS id 08F49B8220C; Tue, 7 Jun 2022 17:23:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6DF1FC385A5; Tue, 7 Jun 2022 17:23:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654622616; bh=7IEAY8SM+tkQYSYabyBmub0Oob3YVAUdvsbXtYkCut4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AaXYjq6WdGcOywHhRI18ivJIj16NNADxg12ZHUJuQjd5GHBtsrJEVY+hXHISljTAP kUWvtwgKeMMyy3k4Qn9WkJMvvZPV+CwimXd/qtqXhnkY9KUv+xKAiIxgVHFhOHciIe 8ae4I96k1RO6rnsbVR0vjhTpP29h7vmTOsJCYoOg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , Jani Nikula , Sasha Levin Subject: [PATCH 5.10 124/452] drm/edid: fix invalid EDID extension block filtering Date: Tue, 7 Jun 2022 18:59:41 +0200 Message-Id: <20220607164912.253781209@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220607164908.521895282@linuxfoundation.org> References: <20220607164908.521895282@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: linux-kernel@vger.kernel.org From: Jani Nikula [ Upstream commit 3aefc722ff52076407203b6af9713de567993adf ] The invalid EDID block filtering uses the number of valid EDID extensions instead of all EDID extensions for looping the extensions in the copy. This is fine, by coincidence, if all the invalid blocks are at the end of the EDID. However, it's completely broken if there are invalid extensions in the middle; the invalid blocks are included and valid blocks are excluded. Fix it by modifying the base block after, not before, the copy. Fixes: 14544d0937bf ("drm/edid: Only print the bad edid when aborting") Reported-by: Ville Syrjälä Signed-off-by: Jani Nikula Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20220330170426.349248-1-jani.nikula@intel.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/drm_edid.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 862e173d3431..4334e466b4e0 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -1995,9 +1995,6 @@ struct edid *drm_do_get_edid(struct drm_connector *connector, connector_bad_edid(connector, edid, edid[0x7e] + 1); - edid[EDID_LENGTH-1] += edid[0x7e] - valid_extensions; - edid[0x7e] = valid_extensions; - new = kmalloc_array(valid_extensions + 1, EDID_LENGTH, GFP_KERNEL); if (!new) @@ -2014,6 +2011,9 @@ struct edid *drm_do_get_edid(struct drm_connector *connector, base += EDID_LENGTH; } + new[EDID_LENGTH - 1] += new[0x7e] - valid_extensions; + new[0x7e] = valid_extensions; + kfree(edid); edid = new; } -- 2.35.1