summaryrefslogtreecommitdiff
path: root/drivers/net
diff options
context:
space:
mode:
authorStefan Hajnoczi <stefanha@redhat.com>2013-01-09 21:59:48 (GMT)
committerDavid S. Miller <davem@davemloft.net>2013-01-10 22:24:10 (GMT)
commit6e331f4c83021e4de2a2fc4981574b5d5b16c425 (patch)
treecc7e9eed80682c95c8a0446b6d92220703aa8c2a /drivers/net
parent21caa6622b36190a32b19dfa734822c2eb93e1fd (diff)
downloadlinux-fsl-qoriq-6e331f4c83021e4de2a2fc4981574b5d5b16c425.tar.xz
tuntap: refuse to re-attach to different tun_struct
Multiqueue tun devices support detaching a tun_file from its tun_struct and re-attaching at a later point in time. This allows users to disable a specific queue temporarily. ioctl(TUNSETIFF) allows the user to specify the network interface to attach by name. This means the user can attempt to attach to interface "B" after detaching from interface "A". The driver is not designed to support this so check we are re-attaching to the right tun_struct. Failure to do so may lead to oops. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net')
-rw-r--r--drivers/net/tun.c2
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index fbd106e..cf6da6e 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -491,6 +491,8 @@ static int tun_attach(struct tun_struct *tun, struct file *file)
err = -EINVAL;
if (rcu_dereference_protected(tfile->tun, lockdep_rtnl_is_held()))
goto out;
+ if (tfile->detached && tun != tfile->detached)
+ goto out;
err = -EBUSY;
if (!(tun->flags & TUN_TAP_MQ) && tun->numqueues == 1)