tuntap: forbid calling TUNSETIFF when detached

[~andy/linux] / drivers / net / tun.c

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index aa963c44450a7e866eaa1c0670dcf36c5f3c147b..a36b56f0940bd9b2718c3ff522c1b6f2c5bc972e 100644 (file)
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -488,8 +488,6 @@ static int tun_attach(struct tun_struct *tun, struct file *file)
        err = -EINVAL;
        if (rtnl_dereference(tfile->tun))
                goto out;
-       if (tfile->detached && tun != tfile->detached)
-               goto out;
 
        err = -EBUSY;
        if (!(tun->flags & TUN_TAP_MQ) && tun->numqueues == 1)
@@ -1543,6 +1541,9 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
        struct net_device *dev;
        int err;
 
+       if (tfile->detached)
+               return -EINVAL;
+
        dev = __dev_get_by_name(net, ifr->ifr_name);
        if (dev) {
                if (ifr->ifr_flags & IFF_TUN_EXCL)