h264: limit allowed pred modes in ff_h264_check_intra_pred_mode() to 3

Higher modes are not allowed for 16x16/chroma, which is what this
function is used for. Otherwise this function would return 0 (vertical
prediction) for invalid higher modes, which could result in invalid
reads.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC:libav-stable@libav.org
This commit is contained in:
Anton Khirnov 2013-11-28 10:54:35 +01:00
parent d1b3fabe69
commit 7f0e81db3c
1 changed files with 3 additions and 3 deletions

View File

@ -534,10 +534,10 @@ int ff_h264_check_intra4x4_pred_mode(H264Context *h)
*/
int ff_h264_check_intra_pred_mode(H264Context *h, int mode, int is_chroma)
{
static const int8_t top[7] = { LEFT_DC_PRED8x8, 1, -1, -1 };
static const int8_t left[7] = { TOP_DC_PRED8x8, -1, 2, -1, DC_128_PRED8x8 };
static const int8_t top[4] = { LEFT_DC_PRED8x8, 1, -1, -1 };
static const int8_t left[5] = { TOP_DC_PRED8x8, -1, 2, -1, DC_128_PRED8x8 };
if (mode > 6U) {
if (mode > 3U) {
av_log(h->avctx, AV_LOG_ERROR,
"out of range intra chroma pred mode at %d %d\n",
h->mb_x, h->mb_y);