[FFmpeg-cvslog] avcodec/webp: Fix null pointer dereference

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Sat May  6 16:43:52 2017 +0200| [9bf4523e40148fdd27064ab570952bd8c4d1016e] | committer: Michael Niedermayer

avcodec/webp: Fix null pointer dereference

Fixes: 1369/clusterfuzz-testcase-minimized-5048908029886464

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

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=9bf4523e40148fdd27064ab570952bd8c4d1016e
---

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

diff --git a/libavcodec/webp.c b/libavcodec/webp.c
index 52a80402e9..d21536a286 100644
--- a/libavcodec/webp.c
+++ b/libavcodec/webp.c
@@ -1342,6 +1342,8 @@ static int vp8_lossy_decode_frame(AVCodecContext *avctx, AVFrame *p,
     pkt.size = data_size;
 
     ret = ff_vp8_decode_frame(avctx, p, got_frame, &pkt);
+    if (ret < 0)
+        return ret;
     if (s->has_alpha) {
         ret = vp8_lossy_decode_alpha(avctx, p, s->alpha_data,
                                      s->alpha_data_size);