redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

[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>
hifive-unleashed-5.1
Patrick McHardy 2007-02-12 11:10:14 -08:00 committed by David S. Miller
parent d486dd1fb8
commit fd706d6957
1 changed files with 8 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
net/netfilter/core.c
View File

@ -61,28 +61,31 @@ EXPORT_SYMBOL_GPL(nf_unregister_afinfo);
* 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(&reg->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(&reg->list);
spin_unlock_bh(&nf_hook_lock);
mutex_unlock(&nf_hook_mutex);
synchronize_net();
}