net_sched: hold tcf_lock in netdevice notifier

We modify mirred action (m->tcfm_dev) in netdev event, we need to
prevent on-going mirred actions from reading freed m->tcfm_dev.
So we need to acquire this spin lock.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Cong Wang 2014-07-16 14:25:31 -07:00 коммит произвёл David S. Miller
Родитель e81fbf6cd6
Коммит 224e923cd9
1 изменённых файлов: 2 добавлений и 0 удалений

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@ -218,10 +218,12 @@ static int mirred_device_event(struct notifier_block *unused,
if (event == NETDEV_UNREGISTER)
list_for_each_entry(m, &mirred_list, tcfm_list) {
spin_lock_bh(&m->tcf_lock);
if (m->tcfm_dev == dev) {
dev_put(dev);
m->tcfm_dev = NULL;
}
spin_unlock_bh(&m->tcf_lock);
}
return NOTIFY_DONE;