diff options
| author | Cong Wang <amwang@redhat.com> | 2013-03-22 19:14:07 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-04-05 10:16:53 -0700 |
| commit | 9829fe9806e22d7a822f4c947cc432c8d1774b54 (patch) | |
| tree | 8aa2ed1051980d96793b92b34663bcc8910fba4d | |
| parent | 01326198867ce1ab1bb26acb48de7b06eab571fe (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.
Signed-off-by: Cong Wang <amwang@redhat.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -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 917ecb93ea2..1e93a917b3d 100644 --- a/net/8021q/vlan.c +++ b/net/8021q/vlan.c @@ -108,13 +108,6 @@ 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); } |