4 files changed, 14 insertions, 5 deletions

diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index 153f6b9e722c..3d870fda8c4f 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -339,6 +339,7 @@ enum vlan_ioctl_cmds {
 enum vlan_flags {
         VLAN_FLAG_REORDER_HDR   = 0x1,
         VLAN_FLAG_GVRP          = 0x2,
+        VLAN_FLAG_LOOSE_BINDING = 0x4,
 };
 
 enum vlan_name_types {
diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c
index 1483243edf14..225aa2fac0e3 100644
--- a/net/8021q/vlan.c
+++ b/net/8021q/vlan.c
@@ -431,6 +431,7 @@ static int vlan_device_event(struct notifier_block *unused, unsigned long event,
         struct vlan_group *grp;
         int i, flgs;
         struct net_device *vlandev;
+        struct vlan_dev_info *vlan;
         LIST_HEAD(list);
 
         if (is_vlan_dev(dev))
@@ -507,7 +508,9 @@ static int vlan_device_event(struct notifier_block *unused, unsigned long event,
                         if (!(flgs & IFF_UP))
                                 continue;
 
-                        dev_change_flags(vlandev, flgs & ~IFF_UP);
+                        vlan = vlan_dev_info(vlandev);
+                        if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
+                                dev_change_flags(vlandev, flgs & ~IFF_UP);
                         vlan_transfer_operstate(dev, vlandev);
                 }
                 break;
@@ -523,7 +526,9 @@ static int vlan_device_event(struct notifier_block *unused, unsigned long event,
                         if (flgs & IFF_UP)
                                 continue;
 
-                        dev_change_flags(vlandev, flgs | IFF_UP);
+                        vlan = vlan_dev_info(vlandev);
+                        if (!(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
+                                dev_change_flags(vlandev, flgs | IFF_UP);
                         vlan_transfer_operstate(dev, vlandev);
                 }
                 break;
diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index de0dc6bacbe8..b7889782047e 100644
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -431,7 +431,8 @@ int vlan_dev_change_flags(const struct net_device *dev, u32 flags, u32 mask)
         struct vlan_dev_info *vlan = vlan_dev_info(dev);
         u32 old_flags = vlan->flags;
 
-        if (mask & ~(VLAN_FLAG_REORDER_HDR | VLAN_FLAG_GVRP))
+        if (mask & ~(VLAN_FLAG_REORDER_HDR | VLAN_FLAG_GVRP |
+                     VLAN_FLAG_LOOSE_BINDING))
                 return -EINVAL;
 
         vlan->flags = (old_flags & ~mask) | (flags & mask);
@@ -456,7 +457,8 @@ static int vlan_dev_open(struct net_device *dev)
         struct net_device *real_dev = vlan->real_dev;
         int err;
 
-        if (!(real_dev->flags & IFF_UP))
+        if (!(real_dev->flags & IFF_UP) &&
+            !(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
                 return -ENETDOWN;
 
         if (compare_ether_addr(dev->dev_addr, real_dev->dev_addr)) {
diff --git a/net/8021q/vlan_netlink.c b/net/8021q/vlan_netlink.c
index 3c9cf6a8e7fb..ddc105734af7 100644
--- a/net/8021q/vlan_netlink.c
+++ b/net/8021q/vlan_netlink.c
@@ -60,7 +60,8 @@ static int vlan_validate(struct nlattr *tb[], struct nlattr *data[])
         if (data[IFLA_VLAN_FLAGS]) {
                 flags = nla_data(data[IFLA_VLAN_FLAGS]);
                 if ((flags->flags & flags->mask) &
-                    ~(VLAN_FLAG_REORDER_HDR | VLAN_FLAG_GVRP))
+                    ~(VLAN_FLAG_REORDER_HDR | VLAN_FLAG_GVRP |
+                      VLAN_FLAG_LOOSE_BINDING))
                         return -EINVAL;
         }