diff options
| author |   Jason Wang <jasowang@redhat.com> | 2013-01-11 16:59:33 +0000 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2013-01-11 19:42:02 -0800 |
| commit | 7c0c3b1a8a175437991ccc898ed66ec5e4a96208 (patch) | |
| tree | 504dde46c8ea52d750ebd5e9e55e8c432beb83db /drivers/net/tun.c | |
| parent | tuntap: switch to use rtnl_dereference() (diff) | |
| download | linux-dev-7c0c3b1a8a175437991ccc898ed66ec5e4a96208.tar.xz linux-dev-7c0c3b1a8a175437991ccc898ed66ec5e4a96208.zip | |
tuntap: forbid calling TUNSETIFF when detached
Michael points out that even after Stefan's fix the TUNSETIFF is still allowed
to create a new tap device. This because we only check tfile->tun but the
tfile->detached were introduced. Fix this by failing early in tun_set_iff() if
the file is detached. After this fix, there's no need to do the check again in
tun_set_iff(), so this patch removes it.
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/tun.c')
| -rw-r--r-- | drivers/net/tun.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index aa963c44450a..a36b56f0940b 100644 --- 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) |