avformat/mvdec: Fix integer overflow with billions of channels

Fixes: signed integer overflow: 1394614304 * 2 cannot be represented in type 'int'
Fixes: 23491/clusterfuzz-testcase-minimized-ffmpeg_DEMUXER_fuzzer-5697377020411904

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 2020-06-23 01:01:53 +02:00
parent 42fdf402a7
commit b6fbbe08c3

View File

@ -268,7 +268,7 @@ static void read_index(AVIOContext *pb, AVStream *st)
avio_skip(pb, 8);
av_add_index_entry(st, pos, timestamp, size, 0, AVINDEX_KEYFRAME);
if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
timestamp += size / (st->codecpar->channels * 2);
timestamp += size / (st->codecpar->channels * 2LL);
} else {
timestamp++;
}
@ -355,7 +355,7 @@ static int mv_read_header(AVFormatContext *avctx)
avio_skip(pb, 8);
av_add_index_entry(ast, pos, timestamp, asize, 0, AVINDEX_KEYFRAME);
av_add_index_entry(vst, pos + asize, i, vsize, 0, AVINDEX_KEYFRAME);
timestamp += asize / (ast->codecpar->channels * 2);
timestamp += asize / (ast->codecpar->channels * 2LL);
}
} else if (!version && avio_rb16(pb) == 3) {
avio_skip(pb, 4);