[FFmpeg-cvslog] avcodec/notchlc: Check bytes left before reading

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Mon Aug 19 20:37:56 2024 +0200| [b9c7f50c7de9b7d8c533eae173c9b77a6719346c] | committer: Michael Niedermayer

avcodec/notchlc: Check bytes left before reading

Fixes: Use of uninitialized value
Fixes: 71230/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_NOTCHLC_fuzzer-4624502095413248

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b9c7f50c7de9b7d8c533eae173c9b77a6719346c
---

 libavcodec/notchlc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavcodec/notchlc.c b/libavcodec/notchlc.c
index 371c8b5e54..246a3e0174 100644
--- a/libavcodec/notchlc.c
+++ b/libavcodec/notchlc.c
@@ -93,6 +93,9 @@ static int lz4_decompress(AVCodecContext *avctx,
             } while (current == 255);
         }
 
+        if (bytestream2_get_bytes_left(gb) < num_literals)
+            return AVERROR_INVALIDDATA;
+
         if (pos + num_literals < HISTORY_SIZE) {
             bytestream2_get_buffer(gb, history + pos, num_literals);
             pos += num_literals;