Merge branch 'vlan-rtnetlink-newlink-fixes'

Eric Dumazet says:

====================
vlan: rtnetlink newlink fixes

First patch fixes a potential memory leak found by syzbot

Second patch makes vlan_changelink() aware of errors
and report them to user.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

net/8021q/vlan.h

@@ -126,6 +126,7 @@ int vlan_check_real_dev(struct net_device *real_dev,
 void vlan_setup(struct net_device *dev);
 int register_vlan_dev(struct net_device *dev, struct netlink_ext_ack *extack);
 void unregister_vlan_dev(struct net_device *dev, struct list_head *head);
+void vlan_dev_uninit(struct net_device *dev);
 bool vlan_dev_inherit_address(struct net_device *dev,
 			      struct net_device *real_dev);
 

net/8021q/vlan_dev.c

@@ -586,7 +586,8 @@ static int vlan_dev_init(struct net_device *dev)
 	return 0;
 }
 
-static void vlan_dev_uninit(struct net_device *dev)
+/* Note: this function might be called multiple times for the same device. */
+void vlan_dev_uninit(struct net_device *dev)
 {
 	struct vlan_priority_tci_mapping *pm;
 	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);

net/8021q/vlan_netlink.c

@@ -108,11 +108,13 @@ static int vlan_changelink(struct net_device *dev, struct nlattr *tb[],
 	struct ifla_vlan_flags *flags;
 	struct ifla_vlan_qos_mapping *m;
 	struct nlattr *attr;
-	int rem;
+	int rem, err;
 
 	if (data[IFLA_VLAN_FLAGS]) {
 		flags = nla_data(data[IFLA_VLAN_FLAGS]);
-		vlan_dev_change_flags(dev, flags->flags, flags->mask);
+		err = vlan_dev_change_flags(dev, flags->flags, flags->mask);
+		if (err)
+			return err;
 	}
 	if (data[IFLA_VLAN_INGRESS_QOS]) {
 		nla_for_each_nested(attr, data[IFLA_VLAN_INGRESS_QOS], rem) {
@@ -123,7 +125,9 @@ static int vlan_changelink(struct net_device *dev, struct nlattr *tb[],
 	if (data[IFLA_VLAN_EGRESS_QOS]) {
 		nla_for_each_nested(attr, data[IFLA_VLAN_EGRESS_QOS], rem) {
 			m = nla_data(attr);
-			vlan_dev_set_egress_priority(dev, m->from, m->to);
+			err = vlan_dev_set_egress_priority(dev, m->from, m->to);
+			if (err)
+				return err;
 		}
 	}
 	return 0;
@@ -179,10 +183,11 @@ static int vlan_newlink(struct net *src_net, struct net_device *dev,
 		return -EINVAL;
 
 	err = vlan_changelink(dev, tb, data, extack);
-	if (err < 0)
+	if (!err)
+		err = register_vlan_dev(dev, extack);
+	if (err)
+		vlan_dev_uninit(dev);
 	return err;
-
-	return register_vlan_dev(dev, extack);
 }
 
 static inline size_t vlan_qos_map_size(unsigned int n)