diff --git a/sys/net/route.c b/sys/net/route.c
index 2bcd4ed87131..c9c7bba142a0 100644
--- a/sys/net/route.c
+++ b/sys/net/route.c
@@ -845,7 +845,7 @@ rt_foreach_fib_walk(int af, rt_setwarg_t *setwa_f, rt_walktree_f_t *wa_f,
 			if (rnh == NULL)
 				continue;
 			if (setwa_f != NULL)
-				setwa_f(rnh, fibnum, i, arg);
+				setwa_f(rnh, fibnum, AF_UNSPEC, arg);
 
 			RADIX_NODE_HEAD_LOCK(rnh);
 			rnh->rnh_walktree(rnh, (walktree_f_t *)wa_f, arg);