From 16127ebb9fcd3aef5fa4c23ada6f6dc5b800d27e Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Sun, 28 Jul 2024 20:53:49 +0200 Subject: [PATCH] avformat/mov: Avoid overflow in dts 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 Fixes: 369662284/clusterfuzz-testcase-minimized-media_metadata_parser_fuzzer-5327368763670528 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 057b8c2066da3554072565744f4f00435cc3342b) Signed-off-by: Michael Niedermayer --- libavformat/mov.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/libavformat/mov.c b/libavformat/mov.c index eae1b49ba5..9c5ce6532d 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -3414,10 +3414,10 @@ 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);