diff options
| author |   stephen hemminger <shemminger@vyatta.com> | 2010-11-15 06:38:13 +0000 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2010-11-15 11:13:17 -0800 |
| commit | b5ed54e94d324f17c97852296d61a143f01b227a (patch) | |
| tree | 2104d3cde24efc1145bc71beb4b61d79ed841132 /net/bridge/br_netfilter.c | |
| parent | netdev: add rcu annotations to receive handler hook (diff) | |
| download | linux-dev-b5ed54e94d324f17c97852296d61a143f01b227a.tar.xz linux-dev-b5ed54e94d324f17c97852296d61a143f01b227a.zip | |
bridge: fix RCU races with bridge port
The macro br_port_exists() is not enough protection when only
RCU is being used. There is a tiny race where other CPU has cleared port
handler hook, but is bridge port flag might still be set.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/bridge/br_netfilter.c')
| -rw-r--r-- | net/bridge/br_netfilter.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c index 865fd7634b67..ce8b2eed4e73 100644 --- a/net/bridge/br_netfilter.c +++ b/net/bridge/br_netfilter.c @@ -131,17 +131,18 @@ void br_netfilter_rtable_init(struct net_bridge *br) static inline struct rtable *bridge_parent_rtable(const struct net_device *dev) { - if (!br_port_exists(dev)) - return NULL; - return &br_port_get_rcu(dev)->br->fake_rtable; + struct net_bridge_port *port; + + port = br_port_get_rcu(dev); + return port ? &port->br->fake_rtable : NULL; } static inline struct net_device *bridge_parent(const struct net_device *dev) { - if (!br_port_exists(dev)) - return NULL; + struct net_bridge_port *port; - return br_port_get_rcu(dev)->br->dev; + port = br_port_get_rcu(dev); + return port ? port->br->dev : NULL; } static inline struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb) |