[FFmpeg-devel] [PATCH 3/4] avcodec/cbs_av1: Fixes: check if the value of cbs_av1_write_uvlc() is supported

[Michael Niedermayer]

Fixes: assertion failure
Fixes: left shift of 1 by 31 places cannot be represented in type 'int'
Fixes: 23264/clusterfuzz-testcase-minimized-ffmpeg_BSF_AV1_METADATA_fuzzer-6308429248593920

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/cbs_av1.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavcodec/cbs_av1.c b/libavcodec/cbs_av1.c
index 29b316e011..4092c9dd06 100644
--- a/libavcodec/cbs_av1.c
+++ b/libavcodec/cbs_av1.c
@@ -125,6 +125,8 @@ static int cbs_av1_write_uvlc(CodedBitstreamContext *ctx, PutBitContext *pbc,
         put_bits(pbc, 1, 1);
     } else {
         zeroes = av_log2(value + 1);
+        if (zeroes > 30)
+            return AVERROR(EINVAL);
         v = value - (1 << zeroes) + 1;
         put_bits(pbc, zeroes + 1, 1);
         put_bits(pbc, zeroes, v);
-- 
2.17.1