webp: fix infinite loop in webp_decode_frame

The loop always needs at least 8 bytes for chunk_type and chunk_size.
If fewer are left, bytestream2_get_le32 just returns 0 without
reading any bytes, leading to an infinite loop.

Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 0762152f7af6cd93bc8f504d5503723500c3f369)
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
(cherry picked from commit 762a5878a6b0bef923ef97c15fdb8274a0351278)

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Andreas Cadhalpun 2015-07-02 23:45:46 +02:00 committed by Michael Niedermayer
parent e812220a30
commit 3c96f21d6e

View File

@ -1387,7 +1387,7 @@ static int webp_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
}
av_dict_free(&s->exif_metadata);
while (bytestream2_get_bytes_left(&gb) > 0) {
while (bytestream2_get_bytes_left(&gb) > 8) {
char chunk_str[5] = { 0 };
chunk_type = bytestream2_get_le32(&gb);