2 files changed, 3 insertions, 0 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 589f0ca668d6..94622e5fb936 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -874,6 +874,8 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
 
         dev = __dev_get_by_name(net, ifr->ifr_name);
         if (dev) {
+                if (ifr->ifr_flags & IFF_TUN_EXCL)
+                        return -EBUSY;
                 if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops)
                         tun = netdev_priv(dev);
                 else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops)
diff --git a/include/linux/if_tun.h b/include/linux/if_tun.h
index 049d6c9428db..915ba5789f0e 100644
--- a/include/linux/if_tun.h
+++ b/include/linux/if_tun.h
@@ -55,6 +55,7 @@
 #define IFF_NO_PI       0x1000
 #define IFF_ONE_QUEUE   0x2000
 #define IFF_VNET_HDR    0x4000
+#define IFF_TUN_EXCL    0x8000
 
 /* Features for GSO (TUNSETOFFLOAD). */
 #define TUN_F_CSUM      0x01    /* You can hand me unchecksummed packets. */