--- /sys/src/cmd/ndb/dnserver.c	Tue May 17 18:32:43 2011
+++ /sys/src/cmd/ndb/dnserver.c	Tue Dec  3 22:23:59 2013
@@ -210,6 +210,7 @@
 	case Tmb:
 	case Tmf:
 	case Tmd:
+		assert(rp->host != nil);
 		hp = rrlookup(rp->host, Ta, NOneg);
 		if(hp == nil)
 			hp = dblookup(rp->host->name, Cin, Ta, 0, 0);
@@ -217,7 +218,8 @@
 			hp = rrlookup(rp->host, Taaaa, NOneg);
 		if(hp == nil)
 			hp = dblookup(rp->host->name, Cin, Taaaa, 0, 0);
-		if (hp && strncmp(hp->owner->name, "local#", 6) == 0)
+		if (hp && hp->owner && hp->owner->name &&
+		    strncmp(hp->owner->name, "local#", 6) == 0)
 			dnslog("returning %s as hint", hp->owner->name);
 		lock(&dnlock);
 		rrcat(last, hp);