| Message ID | 20240728202053.3120590-1-michael@niedermayer.cc |
|---|---|
| State | New |
| Headers | show |
| Series | [FFmpeg-devel,1/2] avformat/mov: Avoid overflow in dts | expand |
| Context | Check | Description |
|---|---|---|
| andriy/make_x86 | success | Make finished |
| andriy/make_fate_x86 | success | Make fate finished |
On Sun, Jul 28, 2024 at 10:20:52PM +0200, Michael Niedermayer wrote: > This basically ignores the overflow without undefined behavior, alternatively we could detect and error out > > Fixes: signed integer overflow: 6310596683470275584 + 7660622966157213696 cannot be represented in type 'long' > Fixes: 70433/clusterfuzz-testcase-minimized-ffmpeg_IO_DEMUXER_fuzzer-5483347233538048 > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > --- > libavformat/mov.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) will apply patchset [...]
diff --git a/libavformat/mov.c b/libavformat/mov.c index b74e43e2140..403af1bba17 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -3472,10 +3472,10 @@ static int mov_read_stts(MOVContext *c, AVIOContext *pb, MOVAtom atom) sc->stts_data[i].duration = 1; corrected_dts += (delta_magnitude < 0 ? (int64_t)delta_magnitude : 1) * sample_count; } else { - corrected_dts += sample_duration * (int64_t)sample_count; + corrected_dts += sample_duration * (uint64_t)sample_count; } - current_dts += sc->stts_data[i].duration * (int64_t)sample_count; + current_dts += sc->stts_data[i].duration * (uint64_t)sample_count; if (current_dts > corrected_dts) { int64_t drift = (current_dts - corrected_dts)/FFMAX(sample_count, 1);
This basically ignores the overflow without undefined behavior, alternatively we could detect and error out Fixes: signed integer overflow: 6310596683470275584 + 7660622966157213696 cannot be represented in type 'long' Fixes: 70433/clusterfuzz-testcase-minimized-ffmpeg_IO_DEMUXER_fuzzer-5483347233538048 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavformat/mov.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)