avcodec/vc1: check REFDIST
authorMichael Niedermayer <michael@niedermayer.cc>
Sat, 31 Aug 2019 20:00:35 +0000 (22:00 +0200)
committerMichael Niedermayer <michael@niedermayer.cc>
Sat, 28 Sep 2019 16:33:20 +0000 (18:33 +0200)
"9.1.1.43 P Reference Distance (REFDIST)"
"The value of REFDIST shall be less than, or equal to, 16."

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
libavcodec/vc1.c

index e102b93..42bfca5 100644 (file)
@@ -933,7 +933,9 @@ int ff_vc1_parse_frame_header_adv(VC1Context *v, GetBitContext* gb)
         else if ((v->s.pict_type != AV_PICTURE_TYPE_B) && (v->s.pict_type != AV_PICTURE_TYPE_BI)) {
             v->refdist = get_bits(gb, 2);
             if (v->refdist == 3)
-                v->refdist += get_unary(gb, 0, 16);
+                v->refdist += get_unary(gb, 0, 14);
+            if (v->refdist > 16)
+                return AVERROR_INVALIDDATA;
         }
         if ((v->s.pict_type == AV_PICTURE_TYPE_B) || (v->s.pict_type == AV_PICTURE_TYPE_BI)) {
             if (read_bfraction(v, gb) < 0)