diff --git a/libavformat/asfdec.c b/libavformat/asfdec.c
index 969ab28875..3b487888ba 100644
--- a/libavformat/asfdec.c
+++ b/libavformat/asfdec.c
@@ -1092,6 +1092,8 @@ static int ff_asf_parse_packet(AVFormatContext *s, AVIOContext *pb, AVPacket *pk
             //printf("packet %d %d\n", asf_st->pkt.size, asf->packet_frag_size);
             asf_st->pkt.size = 0;
             asf_st->pkt.data = 0;
+            asf_st->pkt.side_data_elems = 0;
+            asf_st->pkt.side_data = NULL;
             break; // packet completed
         }
     }