From e4948bb2cdd1c8d1b6fc357e5b817170612aae33 Mon Sep 17 00:00:00 2001
From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Mon, 3 Jul 2023 16:04:30 +0900
Subject: [PATCH] test-network: add test for static route with preferred source

This adds possible reproducer for issue #28009 (though, the issue is
highly racy, hence this may not trigger the issue reliably).
---
 .../conf/25-route-preferred-source.network        | 12 ++++++++++++
 test/test-network/systemd-networkd-tests.py       | 15 +++++++++++++++
 2 files changed, 27 insertions(+)
 create mode 100644 test/test-network/conf/25-route-preferred-source.network

diff --git a/test/test-network/conf/25-route-preferred-source.network b/test/test-network/conf/25-route-preferred-source.network
new file mode 100644
index 00000000000..5a55460349b
--- /dev/null
+++ b/test/test-network/conf/25-route-preferred-source.network
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: LGPL-2.1-or-later
+[Match]
+Name=dummy98
+
+[Network]
+Address=2001:1234:56:8f63::1/64
+IPv6AcceptRA=no
+
+[Route]
+Destination=abcd::/16
+Gateway=2001:1234:56:8f63::1:1
+PreferredSource=2001:1234:56:8f63::1
diff --git a/test/test-network/systemd-networkd-tests.py b/test/test-network/systemd-networkd-tests.py
index 1d426ee9798..902614712e8 100755
--- a/test/test-network/systemd-networkd-tests.py
+++ b/test/test-network/systemd-networkd-tests.py
@@ -2975,6 +2975,21 @@ class NetworkdNetworkTests(unittest.TestCase, Utilities):
         print(output)
         self.assertIn('abcd::/16 via 2001:1234:56:8f63::1:1 proto static src 2001:1234:56:8f63::2', output)
 
+    def test_route_preferred_source_with_existing_address(self):
+        # See issue #28009.
+        copy_network_unit('25-route-preferred-source.network', '12-dummy.netdev')
+        start_networkd()
+
+        for i in range(3):
+            if i != 0:
+                networkctl_reconfigure('dummy98')
+
+            self.wait_online(['dummy98:routable'])
+
+            output = check_output('ip -6 route list dev dummy98')
+            print(output)
+            self.assertIn('abcd::/16 via 2001:1234:56:8f63::1:1 proto static src 2001:1234:56:8f63::1', output)
+
     def test_ip_link_mac_address(self):
         copy_network_unit('25-address-link-section.network', '12-dummy.netdev')
         start_networkd()
-- 
2.47.3