[FFmpeg-devel] [PATCH 3/4] avcodec/svq1dec: Check that there is data left after the hader

[Michael Niedermayer]

Fixes: Timeout (21sec -> 255ms)
Fixes: 20709/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SVQ1_fuzzer-5085075089915904

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/svq1dec.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavcodec/svq1dec.c b/libavcodec/svq1dec.c
index d3e60c3a4a..b61ae348d2 100644
--- a/libavcodec/svq1dec.c
+++ b/libavcodec/svq1dec.c
@@ -602,6 +602,8 @@ static int svq1_decode_frame_header(AVCodecContext *avctx, AVFrame *frame)
         if (skip_1stop_8data_bits(bitbuf) < 0)
             return AVERROR_INVALIDDATA;
     }
+    if (get_bits_left(bitbuf) <= 0)
+        return AVERROR_INVALIDDATA;
 
     s->width  = width;
     s->height = height;
-- 
2.17.1