avcodec/ituh263dec: Check input for minimal frame size
authorMichael Niedermayer <michael@niedermayer.cc>
Mon, 23 Sep 2019 22:42:04 +0000 (00:42 +0200)
committerMichael Niedermayer <michael@niedermayer.cc>
Tue, 8 Oct 2019 14:24:58 +0000 (16:24 +0200)
Fixes: Timeout (28sec -> 3sec)
Fixes: 17559/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H263_fuzzer-5681050776240128

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
libavcodec/ituh263dec.c

index c37f872..c1005b0 100644 (file)
@@ -1218,6 +1218,11 @@ int ff_h263_decode_picture_header(MpegEncContext *s)
     if ((ret = av_image_check_size(s->width, s->height, 0, s)) < 0)
         return ret;
 
+    if (!(s->avctx->flags2 & AV_CODEC_FLAG2_CHUNKS)) {
+        if ((s->width * s->height / 256 / 8) > get_bits_left(&s->gb))
+            return AVERROR_INVALIDDATA;
+    }
+
     s->mb_width = (s->width  + 15) / 16;
     s->mb_height = (s->height  + 15) / 16;
     s->mb_num = s->mb_width * s->mb_height;