resolved: fix accounting of dns serves on a link (#3291)

After a few link up/down events I got this warning:
May 17 22:05:10 laptop systemd-resolved[2983]: Failed to read DNS servers for interface wlp3s0, ignoring: Argument list too long

diff --git a/src/resolve/resolved-dns-server.c b/src/resolve/resolved-dns-server.c
index 49d488c..3095c04 100644 (file)
--- a/src/resolve/resolved-dns-server.c
+++ b/src/resolve/resolved-dns-server.c
@@ -157,6 +157,7 @@ void dns_server_unlink(DnsServer *s) {
                 assert(s->link);
                 assert(s->link->n_dns_servers > 0);
                 LIST_REMOVE(servers, s->link->dns_servers, s);
+                s->link->n_dns_servers--;
                 break;
 
         case DNS_SERVER_SYSTEM: