Index: uspace/lib/c/generic/ns.c
===================================================================
--- uspace/lib/c/generic/ns.c	(revision 1ab4aca491cf0003d347c3cd744f19376766cddd)
+++ uspace/lib/c/generic/ns.c	(revision 54935cf6fe01590e96323ab8738b02418aaba26c)
@@ -75,7 +75,12 @@
 {
 	async_exch_t *exch = async_exchange_begin(session_ns);
+	if (!exch)
+		return NULL;
 	async_sess_t *sess =
 	    async_connect_me_to_blocking(mgmt, exch, service, arg2, arg3);
 	async_exchange_end(exch);
+
+	if (!sess)
+		return NULL;
 	
 	/*