avcodec/iff: Check length before memcpy() in decode_deep_rle32()

Fixes: out of array read
Fixes: 20796/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_IFF_ILBM_fuzzer-5111364702175232.fuzz

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit b4a33387cb1cd3f4c5036e65e0fdd953c6b5012f)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2020-04-21 00:03:40 +02:00
parent bedf686d5b
commit c2fd7070d4

View File

@ -652,6 +652,8 @@ static void decode_deep_rle32(uint8_t *dst, const uint8_t *src, int src_size, in
int size = opcode + 1;
for (i = 0; i < size; i++) {
int length = FFMIN(size - i, width);
if (src_end - src < length * 4)
return;
memcpy(dst + y*linesize + x * 4, src, length * 4);
src += length * 4;
x += length;