diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index 23e4242f2331..05844a2549f2 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -2732,7 +2732,9 @@ add_addr_ports_tests()
 	if reset "signal address with port"; then
 		pm_nl_set_limits $ns1 0 1
 		pm_nl_set_limits $ns2 1 1
-		pm_nl_add_endpoint $ns1 10.0.2.1 flags signal port 10100
+		pm_nl_add_endpoint $ns1 10.0.2.1 dev ns1eth2 flags signal port 10100
+		check_output "pm_nl_show_endpoints ${ns1}" \
+			"$(mptcp_lib_format_endpoints "1,10.0.2.1,signal,ns1eth2,10100")"
 		run_tests $ns1 $ns2 10.0.1.1
 		chk_join_nr 1 1 1
 		chk_add_nr 1 1 1