vlan: fail early when creating netdev named config

Similarly, vlan will create  /proc/net/vlan/<dev>, so when we
create dev with name "config", it will confict with
/proc/net/vlan/config.

Reported-by: Stephane Chazelas <stephane.chazelas@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c
index cba9c212a730059be075a93eedbd825aea6a696a..64c6bed4a3d3aa4545f596a1a146f1d053db949c 100644 (file)
--- a/net/8021q/vlan.c
+++ b/net/8021q/vlan.c
@@ -325,23 +325,24 @@ static void vlan_transfer_features(struct net_device *dev,
        netdev_update_features(vlandev);
 }
 
-static void __vlan_device_event(struct net_device *dev, unsigned long event)
+static int __vlan_device_event(struct net_device *dev, unsigned long event)
 {
+       int err = 0;
+
        switch (event) {
        case NETDEV_CHANGENAME:
                vlan_proc_rem_dev(dev);
-               if (vlan_proc_add_dev(dev) < 0)
-                       pr_warn("failed to change proc name for %s\n",
-                               dev->name);
+               err = vlan_proc_add_dev(dev);
                break;
        case NETDEV_REGISTER:
-               if (vlan_proc_add_dev(dev) < 0)
-                       pr_warn("failed to add proc entry for %s\n", dev->name);
+               err = vlan_proc_add_dev(dev);
                break;
        case NETDEV_UNREGISTER:
                vlan_proc_rem_dev(dev);
                break;
        }
+
+       return err;
 }
 
 static int vlan_device_event(struct notifier_block *unused, unsigned long event,
@@ -356,8 +357,12 @@ static int vlan_device_event(struct notifier_block *unused, unsigned long event,
        bool last = false;
        LIST_HEAD(list);
 
-       if (is_vlan_dev(dev))
-               __vlan_device_event(dev, event);
+       if (is_vlan_dev(dev)) {
+               int err = __vlan_device_event(dev, event);
+
+               if (err)
+                       return notifier_from_errno(err);
+       }
 
        if ((event == NETDEV_UP) &&
            (dev->features & NETIF_F_HW_VLAN_CTAG_FILTER)) {

diff --git a/net/8021q/vlanproc.c b/net/8021q/vlanproc.c
index 1d0e89213a28e8e9200a2ead740c6980f9be46c5..ae63cf72a953ca0f733b7b9e8cfb61dc9012da3c 100644 (file)
--- a/net/8021q/vlanproc.c
+++ b/net/8021q/vlanproc.c
@@ -171,6 +171,8 @@ int vlan_proc_add_dev(struct net_device *vlandev)
        struct vlan_dev_priv *vlan = vlan_dev_priv(vlandev);
        struct vlan_net *vn = net_generic(dev_net(vlandev), vlan_net_id);
 
+       if (!strcmp(vlandev->name, name_conf))
+               return -EINVAL;
        vlan->dent =
                proc_create_data(vlandev->name, S_IFREG|S_IRUSR|S_IWUSR,
                                 vn->proc_vlan_dir, &vlandev_fops, vlandev);