diff --git a/tools/testing/selftests/net/rtnetlink.sh b/tools/testing/selftests/net/rtnetlink.sh
index 38be9706c45f1..26827ea4e3e5f 100755
--- a/tools/testing/selftests/net/rtnetlink.sh
+++ b/tools/testing/selftests/net/rtnetlink.sh
@@ -297,7 +297,7 @@ kci_test_addrlft()
 	done
 
 	sleep 5
-	run_cmd_grep "10.23.11." ip addr show dev "$devdummy"
+	run_cmd_grep_fail "10.23.11." ip addr show dev "$devdummy"
 	if [ $? -eq 0 ]; then
 		check_err 1
 		end_test "FAIL: preferred_lft addresses remaining"