diff options
Diffstat (limited to 'net/ipv4/netfilter/nf_nat_masquerade_ipv4.c')
| -rw-r--r-- | net/ipv4/netfilter/nf_nat_masquerade_ipv4.c | 38 |
1 files changed, 30 insertions, 8 deletions
diff --git a/net/ipv4/netfilter/nf_nat_masquerade_ipv4.c b/net/ipv4/netfilter/nf_nat_masquerade_ipv4.c index a9d5e013e555..41327bb99093 100644 --- a/net/ipv4/netfilter/nf_nat_masquerade_ipv4.c +++ b/net/ipv4/netfilter/nf_nat_masquerade_ipv4.c @@ -147,28 +147,50 @@ static struct notifier_block masq_inet_notifier = { .notifier_call = masq_inet_event, }; -static atomic_t masquerade_notifier_refcount = ATOMIC_INIT(0); +static int masq_refcnt; +static DEFINE_MUTEX(masq_mutex); -void nf_nat_masquerade_ipv4_register_notifier(void) +int nf_nat_masquerade_ipv4_register_notifier(void) { + int ret = 0; + + mutex_lock(&masq_mutex); /* check if the notifier was already set */ - if (atomic_inc_return(&masquerade_notifier_refcount) > 1) - return; + if (++masq_refcnt > 1) + goto out_unlock; /* Register for device down reports */ - register_netdevice_notifier(&masq_dev_notifier); + ret = register_netdevice_notifier(&masq_dev_notifier); + if (ret) + goto err_dec; /* Register IP address change reports */ - register_inetaddr_notifier(&masq_inet_notifier); + ret = register_inetaddr_notifier(&masq_inet_notifier); + if (ret) + goto err_unregister; + + mutex_unlock(&masq_mutex); + return ret; + +err_unregister: + unregister_netdevice_notifier(&masq_dev_notifier); +err_dec: + masq_refcnt--; +out_unlock: + mutex_unlock(&masq_mutex); + return ret; } EXPORT_SYMBOL_GPL(nf_nat_masquerade_ipv4_register_notifier); void nf_nat_masquerade_ipv4_unregister_notifier(void) { + mutex_lock(&masq_mutex); /* check if the notifier still has clients */ - if (atomic_dec_return(&masquerade_notifier_refcount) > 0) - return; + if (--masq_refcnt > 0) + goto out_unlock; unregister_netdevice_notifier(&masq_dev_notifier); unregister_inetaddr_notifier(&masq_inet_notifier); +out_unlock: + mutex_unlock(&masq_mutex); } EXPORT_SYMBOL_GPL(nf_nat_masquerade_ipv4_unregister_notifier); |