ffmpeg | branch: master | Michael Niedermayer <michael@niedermayer.cc> | Sat Oct 17 23:50:57 2020 +0200| [7b2244565ac8cb1eddd085e1a382a893ac03bfb4] | committer: Michael Niedermayer avformat/wavdec: Refuse to read chunks bigger than the filesize in w64_read_header() Fixes: OOM Fixes: 26414/clusterfuzz-testcase-minimized-ffmpeg_dem_FWSE_fuzzer-5070632544632832 Fixes: 26475/clusterfuzz-testcase-minimized-ffmpeg_dem_W64_fuzzer-5770207722995712 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=7b2244565ac8cb1edd...

libavformat/wavdec.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/libavformat/wavdec.c b/libavformat/wavdec.c index bca186a66f..a81f2c7a67 100644 --- a/libavformat/wavdec.c +++ b/libavformat/wavdec.c @@ -902,6 +902,7 @@ static int w64_read_header(AVFormatContext *s) } else if (!memcmp(guid, ff_w64_guid_summarylist, 16)) { int64_t start, end, cur; uint32_t count, chunk_size, i; + int64_t filesize = avio_size(s->pb); start = avio_tell(pb); end = start + FFALIGN(size, INT64_C(8)) - 24; @@ -916,7 +917,7 @@ static int w64_read_header(AVFormatContext *s) chunk_key[4] = 0; avio_read(pb, chunk_key, 4); chunk_size = avio_rl32(pb); - if (chunk_size == UINT32_MAX) + if (chunk_size == UINT32_MAX || (filesize >= 0 && chunk_size > filesize)) return AVERROR_INVALIDDATA; value = av_mallocz(chunk_size + 1);