From 173b0285c5ac46e4040da6e062d637657b47dad2 Mon Sep 17 00:00:00 2001 From: Dave Airlie Date: Tue, 3 May 2016 15:38:37 +1000 Subject: [PATCH] UPSTREAM: drm/edid: move displayid validation to it's own function. We need to use this for validating modeline additions. Change-Id: Idda40c52ff9372433e8bf81e1df5af7b59ce9b4c Signed-off-by: Dave Airlie Signed-off-by: Zheng Yang (cherry picked from commit c97291774c1b867b56c3d439ddaec9a965cf559e) --- drivers/gpu/drm/drm_edid.c | 44 ++++++++++++++++++++++---------------- 1 file changed, 26 insertions(+), 18 deletions(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 200aa3997bc6..dafcfdbdb716 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -4269,6 +4269,29 @@ static void drm_add_display_info(struct edid *edid, info->color_formats |= DRM_COLOR_FORMAT_YCRCB422; } +static int validate_displayid(u8 *displayid, int length, int idx) +{ + int i; + u8 csum = 0; + struct displayid_hdr *base; + + base = (struct displayid_hdr *)&displayid[idx]; + + DRM_DEBUG_KMS("base revision 0x%x, length %d, %d %d\n", + base->rev, base->bytes, base->prod_id, base->ext_count); + + if (base->bytes + 5 > length - idx) + return -EINVAL; + for (i = idx; i <= base->bytes + 5; i++) { + csum += displayid[i]; + } + if (csum) { + DRM_ERROR("DisplayID checksum invalid, remainder is %d\n", csum); + return -EINVAL; + } + return 0; +} + /** * drm_add_edid_modes - add modes from EDID data, if available * @connector: connector we're probing @@ -4596,30 +4619,15 @@ static int drm_parse_display_id(struct drm_connector *connector, { /* if this is an EDID extension the first byte will be 0x70 */ int idx = 0; - struct displayid_hdr *base; struct displayid_block *block; - u8 csum = 0; - int i; int ret; if (is_edid_extension) idx = 1; - base = (struct displayid_hdr *)&displayid[idx]; - - DRM_DEBUG_KMS("base revision 0x%x, length %d, %d %d\n", - base->rev, base->bytes, base->prod_id, base->ext_count); - - if (base->bytes + 5 > length - idx) - return -EINVAL; - - for (i = idx; i <= base->bytes + 5; i++) { - csum += displayid[i]; - } - if (csum) { - DRM_ERROR("DisplayID checksum invalid, remainder is %d\n", csum); - return -EINVAL; - } + ret = validate_displayid(displayid, length, idx); + if (ret) + return ret; idx += sizeof(struct displayid_hdr); while (block = (struct displayid_block *)&displayid[idx], -- 2.34.1