diff options
| author | Michael Niedermayer | 2019-11-15 23:00:51 +0100 |
|---|---|---|
| committer | Michael Niedermayer | 2019-12-31 19:51:57 +0100 |
| commit | 747245ce0e48eccc4a5ad5e6be529f6c9f0d91e4 (patch) | |
| tree | 6e5432d9349a775a1009f9300436fc16d196d78f | |
| parent | 1f88bbc9f2c74f39d8e3ba86ed01cae896dd474c (diff) | |
avformat/rmdec: Initialize and sanity check offset in ivr_read_header()
Fixes: signed integer overflow: -9223372036854775808 - 17 cannot be represented in type 'long'
Fixes: 18768/clusterfuzz-testcase-minimized-ffmpeg_DEMUXER_fuzzer-5674385247830016
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 7e665e4a81e2e96eb45138a1dfa38617de2631a4)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
| -rw-r--r-- | libavformat/rmdec.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/libavformat/rmdec.c b/libavformat/rmdec.c index c9abd38d33..7c24b3a12d 100644 --- a/libavformat/rmdec.c +++ b/libavformat/rmdec.c @@ -1174,7 +1174,7 @@ static int ivr_read_header(AVFormatContext *s) uint8_t key[256], val[256]; AVIOContext *pb = s->pb; AVStream *st; - int64_t pos, offset, temp; + int64_t pos, offset=0, temp; pos = avio_tell(pb); tag = avio_rl32(pb); @@ -1191,6 +1191,8 @@ static int ivr_read_header(AVFormatContext *s) offset = temp; temp = avio_rb64(pb); } + if (offset <= 0) + return AVERROR_INVALIDDATA; avio_skip(pb, offset - avio_tell(pb)); if (avio_r8(pb) != 1) return AVERROR_INVALIDDATA; |