summaryrefslogtreecommitdiffstats
path: root/net/bridge/br_netlink.c
diff options
context:
space:
mode:
authorstephen hemminger <shemminger@vyatta.com>2010-11-15 06:38:13 +0000
committerDavid S. Miller <davem@davemloft.net>2010-11-15 11:13:17 -0800
commitb5ed54e94d324f17c97852296d61a143f01b227a (patch)
tree2104d3cde24efc1145bc71beb4b61d79ed841132 /net/bridge/br_netlink.c
parent61391cde9eefac5cfcf6d214aa80c77e58b1626b (diff)
downloadlinux-b5ed54e94d324f17c97852296d61a143f01b227a.tar.bz2
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_netlink.c')
-rw-r--r--net/bridge/br_netlink.c10
1 files changed, 6 insertions, 4 deletions
diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index 4a6a378c84e3..e3de0a428f5d 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -119,11 +119,13 @@ static int br_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
idx = 0;
for_each_netdev(net, dev) {
+ struct net_bridge_port *port = br_port_get(dev);
+
/* not a bridge port */
- if (!br_port_exists(dev) || idx < cb->args[0])
+ if (!port || idx < cb->args[0])
goto skip;
- if (br_fill_ifinfo(skb, br_port_get(dev),
+ if (br_fill_ifinfo(skb, port,
NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq, RTM_NEWLINK,
NLM_F_MULTI) < 0)
@@ -169,9 +171,9 @@ static int br_rtm_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
if (!dev)
return -ENODEV;
- if (!br_port_exists(dev))
- return -EINVAL;
p = br_port_get(dev);
+ if (!p)
+ return -EINVAL;
/* if kernel STP is running, don't allow changes */
if (p->br->stp_enabled == BR_KERNEL_STP)