[zebra] do not touch socket before pidfile locking

Move zserv socket creation code into zebra_zserv_socket_init() and
call it only after pidfile lock has been acquired exclusively. This
keeps subsequent zebra daemons from deleting the working socket of
an already running process (bug #403).

3 files changed, 15 insertions, 7 deletions

diff --git a/zebra/main.c b/zebra/main.c
index 14b0273c..2d6a4ac8 100644
--- a/zebra/main.c
+++ b/zebra/main.c
@@ -382,6 +382,9 @@ main (int argc, char **argv)
   /* Needed for BSD routing socket. */
   pid = getpid ();
 
+  /* This must be done only after locking pidfile (bug #403). */
+  zebra_zserv_socket_init ();
+
   /* Make vty server socket. */
   vty_serv_sock (vty_addr, vty_port, ZEBRA_VTYSH_PATH);
 
diff --git a/zebra/zserv.c b/zebra/zserv.c
index a566e6d4..cb5e411c 100644
--- a/zebra/zserv.c
+++ b/zebra/zserv.c
@@ -1704,13 +1704,6 @@ zebra_init (void)
   /* Client list init. */
   zebrad.client_list = list_new ();
 
-  /* Make zebra server socket. */
-#ifdef HAVE_TCP_ZEBRA
-  zebra_serv ();
-#else
-  zebra_serv_un (ZEBRA_SERV_PATH);
-#endif /* HAVE_TCP_ZEBRA */
-
   /* Install configuration write function. */
   install_node (&table_node, config_write_table);
   install_node (&forwarding_node, config_write_forwarding);
@@ -1737,3 +1730,14 @@ zebra_init (void)
   /* Route-map */
   zebra_route_map_init ();
 }
+
+/* Make zebra server socket, wiping any existing one (see bug #403). */
+void
+zebra_zserv_socket_init (void)
+{
+#ifdef HAVE_TCP_ZEBRA
+  zebra_serv ();
+#else
+  zebra_serv_un (ZEBRA_SERV_PATH);
+#endif /* HAVE_TCP_ZEBRA */
+}
diff --git a/zebra/zserv.h b/zebra/zserv.h
index 87a33a45..a7371830 100644
--- a/zebra/zserv.h
+++ b/zebra/zserv.h
@@ -89,6 +89,7 @@ struct zebra_t
 /* Prototypes. */
 extern void zebra_init (void);
 extern void zebra_if_init (void);
+extern void zebra_zserv_socket_init (void);
 extern void hostinfo_get (void);
 extern void rib_init (void);
 extern void interface_list (void);