avcodec/vc1dec: Require res_sprite for wmv3images
authorMichael Niedermayer <michael@niedermayer.cc>
Thu, 15 Aug 2019 18:04:35 +0000 (20:04 +0200)
committerMichael Niedermayer <michael@niedermayer.cc>
Sat, 31 Aug 2019 16:34:05 +0000 (18:34 +0200)
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@niedermayer.cc>
libavcodec/vc1dec.c

index 9519864c558172d85b9126f5b12f426deec4de3e..ac3198e4fd69a866d653ad5f33a40e6fb3905f09 100644 (file)
@@ -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",