networkd: fix dhcp4 link without routes not being considered ready (#8728)

The dhcp4 code sets link->dhcp4_configured when dhcp4_route_handler()
has processed the last message.

However, in case UseRoutes=no has been set in the [DHCP] section, or
in case the DHCP server simply sends no routes, link_set_dhcp_routes()
will not send any netlink messages and dhcp4_route_handler() will
therefore never be called.

This causes the link to never reach LINK_STATE_CONFIGURED, and e.g.
systemd-networkd-wait-online will not consider the link as ready.

Fix that by setting link->dhcp4_configured = true and calling
link_check_ready() in dhcp4_address_handler() in case
link_set_dhcp_routes() sent no netlink messages (dhcp4_messages is
zero).

diff --git a/src/network/networkd-dhcp4.c b/src/network/networkd-dhcp4.c
index acd0e68a61ebe31e6c0df3a3633b4f6a01d8df77..6bab7647d67b7ee96aa0e16d993be5d387f3b1d7 100644 (file)
--- a/src/network/networkd-dhcp4.c
+++ b/src/network/networkd-dhcp4.c
@@ -319,6 +319,11 @@ static int dhcp4_address_handler(sd_netlink *rtnl, sd_netlink_message *m,
 
         link_set_dhcp_routes(link);
 
+        if (link->dhcp4_messages == 0) {
+                link->dhcp4_configured = true;
+                link_check_ready(link);
+        }
+
         return 1;
 }