diff options
author | Michael Niedermayer <michael@niedermayer.cc> | 2021-01-12 21:17:18 +0100 |
---|---|---|
committer | Michael Niedermayer <michael@niedermayer.cc> | 2021-09-11 21:23:48 +0200 |
commit | 21b22a76d672f97e214ac5f2f39ac7fe8e47fa71 (patch) | |
tree | 9608c5a22080b24b1dacaba58b1c595f376f3236 | |
parent | 13c058d51cea4d82acbc0ad9761a7cb853daea17 (diff) | |
download | ffmpeg-21b22a76d672f97e214ac5f2f39ac7fe8e47fa71.tar.gz |
avformat/asfdec_o: Check size vs. offset in detect_unknown_subobject()
Fixes: signed integer overflow: 2314885530818453566 + 7503032301549264928 cannot be represented in type 'long'
Fixes: 26639/clusterfuzz-testcase-minimized-ffmpeg_dem_ASF_O_fuzzer-6024222100684800
Alternatively this could be ignored but then the end condition of the loop
would be hard to reach as avio_tell() is int64_t
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 0bee216ad454dd7238a03dd9a76428cc6c3233cc)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
-rw-r--r-- | libavformat/asfdec_o.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/libavformat/asfdec_o.c b/libavformat/asfdec_o.c index b4b2698368..6174cfae2c 100644 --- a/libavformat/asfdec_o.c +++ b/libavformat/asfdec_o.c @@ -1679,6 +1679,9 @@ static int detect_unknown_subobject(AVFormatContext *s, int64_t offset, int64_t ff_asf_guid guid; int ret; + if (offset > INT64_MAX - size) + return AVERROR_INVALIDDATA; + while (avio_tell(pb) <= offset + size) { if (avio_tell(pb) == asf->offset) break; |