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| author | Michael Niedermayer <michael@niedermayer.cc> | 2020-10-28 20:11:54 +0100 |
|---|---|---|
| committer | Michael Niedermayer <michael@niedermayer.cc> | 2020-11-04 23:30:53 +0100 |
| commit | 27a99e2c7d450fef15594671eef4465c8a166bd7 (patch) | |
| tree | eeeca163a5d147ad2d437ee1d6d7f37f00f25f81 /libavformat | |
| parent | 437b7302b09a04e0fbfcd594114b52c5c6d89d32 (diff) | |
| download | ffmpeg-27a99e2c7d450fef15594671eef4465c8a166bd7.tar.gz | |
avformat/vividas: improve extradata packing checks in track_header()
Fixes: out of array accesses
Fixes: 26622/clusterfuzz-testcase-minimized-ffmpeg_dem_VIVIDAS_fuzzer-6581200338288640
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Diffstat (limited to 'libavformat')
| -rw-r--r-- | libavformat/vividas.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/libavformat/vividas.c b/libavformat/vividas.c index 83d0ed1167..46c66bf9a0 100644 --- a/libavformat/vividas.c +++ b/libavformat/vividas.c @@ -28,6 +28,7 @@ * @sa http://wiki.multimedia.cx/index.php?title=Vividas_VIV */ +#include "libavutil/avassert.h" #include "libavutil/intreadwrite.h" #include "avio_internal.h" #include "avformat.h" @@ -379,7 +380,7 @@ static int track_header(VividasDemuxContext *viv, AVFormatContext *s, uint8_t * if (avio_tell(pb) < off) { int num_data; - int xd_size = 0; + int xd_size = 1; int data_len[256]; int offset = 1; uint8_t *p; @@ -393,10 +394,10 @@ static int track_header(VividasDemuxContext *viv, AVFormatContext *s, uint8_t * return AVERROR_INVALIDDATA; } data_len[j] = len; - xd_size += len; + xd_size += len + 1 + len/255; } - ret = ff_alloc_extradata(st->codecpar, 64 + xd_size + xd_size / 255); + ret = ff_alloc_extradata(st->codecpar, xd_size); if (ret < 0) return ret; @@ -405,9 +406,7 @@ static int track_header(VividasDemuxContext *viv, AVFormatContext *s, uint8_t * for (j = 0; j < num_data - 1; j++) { unsigned delta = av_xiphlacing(&p[offset], data_len[j]); - if (delta > data_len[j]) { - return AVERROR_INVALIDDATA; - } + av_assert0(delta <= xd_size - offset); offset += delta; } @@ -418,6 +417,7 @@ static int track_header(VividasDemuxContext *viv, AVFormatContext *s, uint8_t * av_freep(&st->codecpar->extradata); break; } + av_assert0(data_len[j] <= xd_size - offset); offset += data_len[j]; } |