diff options
| -rw-r--r-- | drivers/gpu/drm/drm_edid.c | 44 |
1 files changed, 26 insertions, 18 deletions
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 0b95a7f2db03..fac4efc7dfe2 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -3901,6 +3901,29 @@ 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 @@ -4212,30 +4235,15 @@ 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], |