[FFmpeg-devel] [PATCH 5/5] avformat/id3v2: Check against max compression ratio before allocation

Michael Niedermayer michael at niedermayer.cc
Sun Nov 29 02:03:37 EET 2020


Fixes: Timeout (>10sec -> 12ms)
Fixes: 27612/clusterfuzz-testcase-minimized-ffmpeg_dem_PCM_S24BE_fuzzer-6605893000757248

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavformat/id3v2.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavformat/id3v2.c b/libavformat/id3v2.c
index 336a3964de..97f6cc8a68 100644
--- a/libavformat/id3v2.c
+++ b/libavformat/id3v2.c
@@ -995,6 +995,8 @@ static void id3v2_parse(AVIOContext *pb, AVDictionary **metadata,
 
                     if (tlen <= 0)
                         goto seek;
+                    if (dlen / 32768 > tlen)
+                        goto seek;
 
                     av_fast_malloc(&uncompressed_buffer, &uncompressed_buffer_size, dlen);
                     if (!uncompressed_buffer) {
-- 
2.17.1



More information about the ffmpeg-devel mailing list