FAILED: patch "[PATCH] drm/edid: fix CEA extension byte #3 parsing" failed to apply to 5.17-stable tree

The patch below does not apply to the 5.17-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 7344bad7fb6daa4877a1c064b52c7d5f9182c41b Mon Sep 17 00:00:00 2001
From: Jani Nikula <[email protected]>
Date: Wed, 23 Mar 2022 12:04:38 +0200
Subject: [PATCH] drm/edid: fix CEA extension byte #3 parsing
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Only an EDID CEA extension has byte #3, while the CTA DisplayID Data Block does not. Don't interpret bogus data for color formats.

For most displays it's probably an unlikely scenario you'd have a CTA DisplayID Data Block without a CEA extension, but they do exist.

index f07af6786cec..cc7bd58369df 100644
@@ -5188,10 +5188,14 @@ static void drm_parse_cea_ext(struct drm_connector *connector,
 
 	/* The existence of a CEA block should imply RGB support */
 	info->color_formats = DRM_COLOR_FORMAT_RGB444;
-	if (edid_ext[3] & EDID_CEA_YCRCB444)
-		info->color_formats |= DRM_COLOR_FORMAT_YCBCR444;
-	if (edid_ext[3] & EDID_CEA_YCRCB422)
-		info->color_formats |= DRM_COLOR_FORMAT_YCBCR422;
+
+	/* CTA DisplayID Data Block does not have byte #3 */
+	if (edid_ext[0] == CEA_EXT) {
+		if (edid_ext[3] & EDID_CEA_YCRCB444)
+			info->color_formats |= DRM_COLOR_FORMAT_YCBCR444;
+		if (edid_ext[3] & EDID_CEA_YCRCB422)
+			info->color_formats |= DRM_COLOR_FORMAT_YCBCR422;
+	}
 
 	if (cea_db_offsets(edid_ext, &start, &end))
 		return;