diff --git a/sys/netinet6/in6.c b/sys/netinet6/in6.c
--- a/sys/netinet6/in6.c
+++ b/sys/netinet6/in6.c
@@ -2700,6 +2700,9 @@
 	struct lltable *llt;
 	bool need_purge;
 
+	if (ifp->if_afdata[AF_INET6] == NULL)
+		return;
+
 	llt = LLTABLE6(ifp);
 	IF_AFDATA_WLOCK(ifp);
 	need_purge = ((llt->llt_flags & LLT_ADDEDPROXY) != 0);