diff options
| author | Cong Wang <amwang@redhat.com> | 2013-03-22 19:14:07 +0000 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2013-04-10 03:20:11 +0100 |
| commit | a7fe44f2340bd4c77428ad97f903ff31e67d6208 (patch) | |
| tree | c6a10a5e2013a60ef6b5aa7c484bd2159ea999e9 /net/8021q | |
| parent | 4289cdeb48d9d5d2674a85e63b315d4771bf4d27 (diff) | |
8021q: fix a potential use-after-free
[ Upstream commit 4a7df340ed1bac190c124c1601bfc10cde9fb4fb ]
vlan_vid_del() could possibly free ->vlan_info after a RCU grace
period, however, we may still refer to the freed memory area
by 'grp' pointer. Found by code inspection.
This patch moves vlan_vid_del() as behind as possible.
Cc: Patrick McHardy <kaber@trash.net>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'net/8021q')
| -rw-r--r-- | net/8021q/vlan.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c index 5471628d3ff..963f285e69c 100644 --- a/net/8021q/vlan.c +++ b/net/8021q/vlan.c @@ -110,13 +110,6 @@ void unregister_vlan_dev(struct net_device *dev, struct list_head *head) grp = rtnl_dereference(real_dev->vlgrp); BUG_ON(!grp); - /* Take it out of our own structures, but be sure to interlock with - * HW accelerating devices or SW vlan input packet processing if - * VLAN is not 0 (leave it there for 802.1p). - */ - if (vlan_id && (real_dev->features & NETIF_F_HW_VLAN_FILTER)) - ops->ndo_vlan_rx_kill_vid(real_dev, vlan_id); - grp->nr_vlans--; if (vlan->flags & VLAN_FLAG_GVRP) @@ -139,6 +132,13 @@ void unregister_vlan_dev(struct net_device *dev, struct list_head *head) call_rcu(&grp->rcu, vlan_rcu_free); } + /* Take it out of our own structures, but be sure to interlock with + * HW accelerating devices or SW vlan input packet processing if + * VLAN is not 0 (leave it there for 802.1p). + */ + if (vlan_id && (real_dev->features & NETIF_F_HW_VLAN_FILTER)) + ops->ndo_vlan_rx_kill_vid(real_dev, vlan_id); + /* Get rid of the vlan's reference to real_dev */ dev_put(real_dev); } |