avcodec/dvdsubdec: Sanity check len in decode_rle()

Fixes: Timeout
Fixes: 9778/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_DVDSUB_fuzzer-5186007132536832

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2018-09-13 03:33:50 +02:00
parent c88afa44c4
commit e7b023e1db

View File

@ -125,6 +125,8 @@ static int decode_rle(uint8_t *bitmap, int linesize, int w, int h, uint8_t used_
len = decode_run_8bit(&gb, &color);
else
len = decode_run_2bit(&gb, &color);
if (len != INT_MAX && len > w - x)
return AVERROR_INVALIDDATA;
len = FFMIN(len, w - x);
memset(d + x, color, len);
used_color[color] = 1;