[FFmpeg-devel] [PATCH 1/4] avformat/apngdec: Check for incomplete reads in append_extradata()

[Michael Niedermayer]

Fixes: OOM
Fixes: 26608/clusterfuzz-testcase-minimized-ffmpeg_dem_APNG_fuzzer-4839491644424192

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/apngdec.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavformat/apngdec.c b/libavformat/apngdec.c
index 0f1d04a365..2e79fdd85c 100644
--- a/libavformat/apngdec.c
+++ b/libavformat/apngdec.c
@@ -140,6 +140,8 @@ static int append_extradata(AVCodecParameters *par, AVIOContext *pb, int len)
 
     if ((ret = avio_read(pb, par->extradata + previous_size, len)) < 0)
         return ret;
+    if (ret < len)
+        return AVERROR_INVALIDDATA;
 
     return previous_size;
 }
-- 
2.17.1