avformat/vividas: Check for zero v_size

Fixes: SEGV on unknown address 0x000000000000
Fixes: 26482/clusterfuzz-testcase-minimized-ffmpeg_dem_VIVIDAS_fuzzer-4905102324006912

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2020-10-22 00:37:30 +02:00
parent d34e4904cd
commit c7a5face77

View File

@ -679,7 +679,7 @@ static int viv_read_packet(AVFormatContext *s,
return AVERROR_INVALIDDATA;
ffio_read_varlen(pb);
if (v_size > INT_MAX)
if (v_size > INT_MAX || !v_size)
return AVERROR_INVALIDDATA;
ret = av_get_packet(pb, pkt, v_size);
if (ret < 0)
@ -708,7 +708,7 @@ static int viv_read_packet(AVFormatContext *s,
} else {
uint64_t v_size = ffio_read_varlen(pb);
if (v_size > INT_MAX)
if (v_size > INT_MAX || !v_size)
return AVERROR_INVALIDDATA;
ret = av_get_packet(pb, pkt, v_size);
if (ret < 0)