Commit 1fb1754a authored by Hong Zhiguo's avatar Hong Zhiguo Committed by David S. Miller
Browse files

bridge: use br_port_get_rtnl within rtnl lock 



current br_port_get_rcu is problematic in bridging path
(NULL deref). Change these calls in netlink path first.

Signed-off-by: default avatarHong Zhiguo <zhiguohong@tencent.com>
Acked-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 3274f687

net/bridge/br_netlink.c

+2 −2
Original line number Diff line number Diff line
@@ -207,7 +207,7 @@ int br_getlink(struct sk_buff *skb, u32 pid, u32 seq, 
	       struct net_device *dev, u32 filter_mask)

{

	int err = 0;

	struct net_bridge_port *port = br_port_get_rcu(dev);

	struct net_bridge_port *port = br_port_get_rtnl(dev);



	/* not a bridge port and  */

	if (!port && !(filter_mask & RTEXT_FILTER_BRVLAN))
@@ -451,7 +451,7 @@ static size_t br_get_link_af_size(const struct net_device *dev) 
	struct net_port_vlans *pv;



	if (br_port_exists(dev))

		pv = nbp_get_vlan_info(br_port_get_rcu(dev));

		pv = nbp_get_vlan_info(br_port_get_rtnl(dev));

	else if (dev->priv_flags & IFF_EBRIDGE)

		pv = br_get_vlan_info((struct net_bridge *)netdev_priv(dev));

	else

net/bridge/br_private.h

+1 −1
Original line number Diff line number Diff line
@@ -208,7 +208,7 @@ static inline struct net_bridge_port *br_port_get_rcu(const struct net_device *d 
	return br_port_exists(dev) ? port : NULL;

}



static inline struct net_bridge_port *br_port_get_rtnl(struct net_device *dev)

static inline struct net_bridge_port *br_port_get_rtnl(const struct net_device *dev)

{

	return br_port_exists(dev) ?

		rtnl_dereference(dev->rx_handler_data) : NULL;