From 30047c052d9d5591f69c8170763e80b5d4a2349b Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael@niedermayer.cc>
Date: Sun, 2 Jun 2019 23:16:40 +0200
Subject: [PATCH] avcodec/fmvc: Check if header fields are available before
 allocating the image

Fixes: Timeout (15sec -> 0.5sec)
Fixes: 14846/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_FMVC_fuzzer-5068322120400896

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 561cc161ca617c1b8d48fef0f02d56c0f1af0486)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavcodec/fmvc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavcodec/fmvc.c b/libavcodec/fmvc.c
index 74e9bdd8a0..9bbe8c6ccf 100644
--- a/libavcodec/fmvc.c
+++ b/libavcodec/fmvc.c
@@ -403,6 +403,9 @@ static int decode_frame(AVCodecContext *avctx,
     AVFrame *frame = data;
     int ret, y, x;
 
+    if (avpkt->size < 8)
+        return AVERROR_INVALIDDATA;
+
     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
         return ret;