Phonet: handle rtnetlink registration failure

Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/phonet/pn_dev.h

@@ -38,7 +38,7 @@ struct phonet_device {
 
 int phonet_device_init(void);
 void phonet_device_exit(void);
-void phonet_netlink_register(void);
+int phonet_netlink_register(void);
 struct net_device *phonet_device_get(struct net *net);
 
 int phonet_address_add(struct net_device *dev, u8 addr);

net/phonet/pn_dev.c

@@ -190,9 +190,13 @@ static struct notifier_block phonet_device_notifier = {
 /* Initialize Phonet devices list */
 int __init phonet_device_init(void)
 {
+	int err;
+
 	register_netdevice_notifier(&phonet_device_notifier);
-	phonet_netlink_register();
-	return 0;
+	err = phonet_netlink_register();
+	if (err)
+		phonet_device_exit();
+	return err;
 }
 
 void phonet_device_exit(void)

net/phonet/pn_netlink.c

@@ -160,9 +160,14 @@ static int getaddr_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
 	return skb->len;
 }
 
-void __init phonet_netlink_register(void)
+int __init phonet_netlink_register(void)
 {
-	rtnl_register(PF_PHONET, RTM_NEWADDR, addr_doit, NULL);
-	rtnl_register(PF_PHONET, RTM_DELADDR, addr_doit, NULL);
-	rtnl_register(PF_PHONET, RTM_GETADDR, NULL, getaddr_dumpit);
+	int err = __rtnl_register(PF_PHONET, RTM_NEWADDR, addr_doit, NULL);
+	if (err)
+		return err;
+
+	/* Further __rtnl_register() cannot fail */
+	__rtnl_register(PF_PHONET, RTM_DELADDR, addr_doit, NULL);
+	__rtnl_register(PF_PHONET, RTM_GETADDR, NULL, getaddr_dumpit);
+	return 0;
 }