[FFmpeg-cvslog] avcodec/vc1dec: Require res_sprite for wmv3images

[Michael Niedermayer]

ffmpeg | branch: release/4.2 | Michael Niedermayer <michael at niedermayer.cc> | Thu Aug 15 20:04:35 2019 +0200| [fd235d74282e480382a2430adc15ee2749b8abfd] | committer: Michael Niedermayer

avcodec/vc1dec: Require res_sprite for wmv3images

non res_sprite leads to decoder delay which leads to assertion failure
Fixes: Assertion failure
Fixes: 16402/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMV3IMAGE_fuzzer-5704510034411520
Fixes: left shift of 1073741824 by 1 places cannot be represented in type 'int'
Fixes: 16425/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WMV3IMAGE_fuzzer-5692858838810624

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 9c6b4004928ef41563b0e913666f8da27fdb2399)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=fd235d74282e480382a2430adc15ee2749b8abfd
---

 libavcodec/vc1dec.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/libavcodec/vc1dec.c b/libavcodec/vc1dec.c
index 9519864c55..ac3198e4fd 100644
--- a/libavcodec/vc1dec.c
+++ b/libavcodec/vc1dec.c
@@ -450,6 +450,11 @@ static av_cold int vc1_decode_init(AVCodecContext *avctx)
         if ((ret = ff_vc1_decode_sequence_header(avctx, v, &gb)) < 0)
           return ret;
 
+        if (avctx->codec_id == AV_CODEC_ID_WMV3IMAGE && !v->res_sprite) {
+            avpriv_request_sample(avctx, "Non sprite WMV3IMAGE");
+            return AVERROR_PATCHWELCOME;
+        }
+
         count = avctx->extradata_size*8 - get_bits_count(&gb);
         if (count > 0) {
             av_log(avctx, AV_LOG_INFO, "Extra data: %i bits left, value: %X\n",