indeo5: check tile size in decode_mb_info().

This prevents writing into a too small array if some parameters changed
without the tile being reallocated.

Fixes CVE-2012-2794

CC:libav-stable@libav.org

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Anton Khirnov <anton@khirnov.net>
This commit is contained in:
Michael Niedermayer 2012-04-15 14:11:50 +02:00 committed by Anton Khirnov
parent e4d4044339
commit 2d09cdbaf2

View File

@ -430,6 +430,12 @@ static int decode_mb_info(IVI45DecContext *ctx, IVIBandDesc *band,
((band->qdelta_present && band->inherit_qdelta) || band->inherit_mv))
return AVERROR_INVALIDDATA;
if (tile->num_MBs != IVI_MBs_PER_TILE(tile->width, tile->height, band->mb_size)) {
av_log(avctx, AV_LOG_ERROR, "Allocated tile size %d mismatches parameters %d\n",
tile->num_MBs, IVI_MBs_PER_TILE(tile->width, tile->height, band->mb_size));
return AVERROR_INVALIDDATA;
}
/* scale factor for motion vectors */
mv_scale = (ctx->planes[0].bands[0].mb_size >> 3) - (band->mb_size >> 3);
mv_x = mv_y = 0;