diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 589f0ca668d6a45f9100af7d39f46ef63929439a..94622e5fb936d8263f5c7bc5bb50c7f433d7230c 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 049d6c9428db60b78dbb49a595e774da001effb0..915ba5789f0eb62c02c1c2664e7ef66b1e631ab5 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. */