From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Tue, 24 Nov 2020 06:47:13 +0000 (+0900)
Subject: network: stop to assign UUID when reconfiguring link
X-Git-Tag: v248-rc1~607^2
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F17707%2Fhead;p=thirdparty%2Fsystemd.git

network: stop to assign UUID when reconfiguring link

This fixes the following race in reconfiguring link:
1. an interface requests UUID.
2. the interface is reconfigured and link_configure() is called.
3. sd-lldp client is started on the interface (it is enabled by default).
4. networkd acquires UUID, and get_product_uuid_handler() calls
   link_configure() for the link again.
5. link_lldp_rx_configure() fails to set ifindex for already running
   sd-lldp client.
6. the link enters failed state.
---

diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index 2b7055dd0fa..547f3bbc012 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -2172,6 +2172,7 @@ static int link_reconfigure_internal(Link *link, sd_netlink_message *m, bool for
         link_free_carrier_maps(link);
         link_free_engines(link);
         link->network = network_unref(link->network);
+        link_unref(set_remove(link->manager->links_requesting_uuid, link));
 
         /* Then, apply new .network file */
         r = network_apply(network, link);