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 37475CCA47C for ; Tue, 7 Jun 2022 18:38:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345827AbiFGSip (ORCPT ); Tue, 7 Jun 2022 14:38:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51776 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344194AbiFGSHz (ORCPT ); Tue, 7 Jun 2022 14:07:55 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5CD483969A; Tue, 7 Jun 2022 10:48:00 -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 B6DD0B8233E; Tue, 7 Jun 2022 17:47:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C57AC34115; Tue, 7 Jun 2022 17:47:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654624054; bh=siwl64RdAseHoxhVxsdB3Xy9Hp3JQLj4fBIMdrwi3tI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oXyShcVPXO0UBnZWoF2mEiYFiiRcH1I1AcUqZwDEXiWB0l7AHCoEe+H62NjpKkcKs FhqjnaAmJ/m8QMX3cayKWRKlhPo7VLcbqZkHs+Q9Vht9Mh/ufVO0a7EKWcwzi6t2Di AWoe405BgeZ741LiJjGcMiEusfpaElD0chG4Jwvo= 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 5.15 189/667] drm/edid: fix invalid EDID extension block filtering Date: Tue, 7 Jun 2022 18:57:34 +0200 Message-Id: <20220607164940.471585998@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220607164934.766888869@linuxfoundation.org> References: <20220607164934.766888869@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 ee6f44f9a81c..6ab048ba8021 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -1994,9 +1994,6 @@ 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) @@ -2013,6 +2010,9 @@ 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