avcodec/zmbv: Check that the buffer is large enough for mvec
authorMichael Niedermayer <michael@niedermayer.cc>
Wed, 15 Nov 2017 16:11:12 +0000 (17:11 +0100)
committerMichael Niedermayer <michael@niedermayer.cc>
Fri, 1 Dec 2017 23:28:59 +0000 (00:28 +0100)
Fixes: Timeout
Fixes: 4143/clusterfuzz-testcase-4736864637419520

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 2ab9568a2c3349039eec29fb960fe39de354b514)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
libavcodec/zmbv.c

index 25a1cd2..39a08db 100644 (file)
@@ -539,6 +539,8 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPac
     } else {
         frame->key_frame = 0;
         frame->pict_type = AV_PICTURE_TYPE_P;
+        if (c->decomp_len < 2LL * ((c->width + c->bw - 1) / c->bw) * ((c->height + c->bh - 1) / c->bh))
+            return AVERROR_INVALIDDATA;
         if (c->decomp_len)
             c->decode_xor(c);
     }