| Message ID | 20210317231728.2130-1-michael@niedermayer.cc |
|---|---|
| State | Accepted |
| Commit | 6cc65d3d6760cfb08c5a9e57d4306d88428e18d0 |
| Headers | show |
| Series | [FFmpeg-devel,1/3] avformat/mpc8: check for size overflow in mpc8_get_chunk_header() | expand |
| Context | Check | Description |
|---|---|---|
| andriy/x86_make | success | Make finished |
| andriy/x86_make_fate | success | Make fate finished |
| andriy/PPC64_make | success | Make finished |
| andriy/PPC64_make_fate | success | Make fate finished |
On Thu, Mar 18, 2021 at 12:17:26AM +0100, Michael Niedermayer wrote: > Fixes: signed integer overflow: -9223372036854775760 - 50 cannot be represented in type 'long' > Fixes: 31673/clusterfuzz-testcase-minimized-ffmpeg_dem_MPC8_fuzzer-580134751869337 > > Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > --- > libavformat/mpc8.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) will apply [...]
diff --git a/libavformat/mpc8.c b/libavformat/mpc8.c index ff7da2ef55..b12a417f63 100644 --- a/libavformat/mpc8.c +++ b/libavformat/mpc8.c @@ -127,7 +127,11 @@ static void mpc8_get_chunk_header(AVIOContext *pb, int *tag, int64_t *size) pos = avio_tell(pb); *tag = avio_rl16(pb); *size = ffio_read_varlen(pb); - *size -= avio_tell(pb) - pos; + pos -= avio_tell(pb); + if (av_sat_add64(*size, pos) != (uint64_t)*size + pos) { + *size = -1; + } else + *size += pos; } static void mpc8_parse_seektable(AVFormatContext *s, int64_t off)
Fixes: signed integer overflow: -9223372036854775760 - 50 cannot be represented in type 'long' Fixes: 31673/clusterfuzz-testcase-minimized-ffmpeg_dem_MPC8_fuzzer-580134751869337 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavformat/mpc8.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)