Merge commit '6fc8226e'

* commit '6fc8226e':
  vp3: Check the framerate for validity

Conflicts:
	libavcodec/vp3.c

See: a56d963fMerged-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/vp3.c

@@ -2225,7 +2225,11 @@ static int theora_decode_header(AVCodecContext *avctx, GetBitContext *gb)
 
     fps.num = get_bits_long(gb, 32);
     fps.den = get_bits_long(gb, 32);
-    if (fps.num>0 && fps.den>0) {
+    if (fps.num && fps.den) {
+        if (fps.num < 0 || fps.den < 0) {
+            av_log(avctx, AV_LOG_ERROR, "Invalid framerate\n");
+            return AVERROR_INVALIDDATA;
+        }
         av_reduce(&avctx->time_base.num, &avctx->time_base.den,
                   fps.den, fps.num, 1<<30);
     }