[NETFILTER]: Switch nf_register_hook/nf_unregister_hook to mutex
The spinlock is only used in process context (register/unregister)
since RCU is used for the nf_hook lists, switch to a mutex.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netfilter/core.c b/net/netfilter/core.c
index 716603f..f61e0c2 100644
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@ -61,28 +61,31 @@
* packets come back: if the hook is gone, the packet is discarded. */
struct list_head nf_hooks[NPROTO][NF_MAX_HOOKS] __read_mostly;
EXPORT_SYMBOL(nf_hooks);
-static DEFINE_SPINLOCK(nf_hook_lock);
+static DEFINE_MUTEX(nf_hook_mutex);
int nf_register_hook(struct nf_hook_ops *reg)
{
struct list_head *i;
+ int err;
- spin_lock_bh(&nf_hook_lock);
+ err = mutex_lock_interruptible(&nf_hook_mutex);
+ if (err < 0)
+ return err;
list_for_each(i, &nf_hooks[reg->pf][reg->hooknum]) {
if (reg->priority < ((struct nf_hook_ops *)i)->priority)
break;
}
list_add_rcu(®->list, i->prev);
- spin_unlock_bh(&nf_hook_lock);
+ mutex_unlock(&nf_hook_mutex);
return 0;
}
EXPORT_SYMBOL(nf_register_hook);
void nf_unregister_hook(struct nf_hook_ops *reg)
{
- spin_lock_bh(&nf_hook_lock);
+ mutex_lock(&nf_hook_mutex);
list_del_rcu(®->list);
- spin_unlock_bh(&nf_hook_lock);
+ mutex_unlock(&nf_hook_mutex);
synchronize_net();
}