diff options
Diffstat (limited to 'net/netfilter/nf_queue.c')
| -rw-r--r-- | net/netfilter/nf_queue.c | 59 |
1 files changed, 35 insertions, 24 deletions
diff --git a/net/netfilter/nf_queue.c b/net/netfilter/nf_queue.c index b1f2ace96f6d..a481a349f7bf 100644 --- a/net/netfilter/nf_queue.c +++ b/net/netfilter/nf_queue.c @@ -17,7 +17,7 @@ */ static struct nf_queue_handler *queue_handler[NPROTO]; -static DEFINE_RWLOCK(queue_handler_lock); +static DEFINE_MUTEX(queue_handler_mutex); /* return EBUSY when somebody else is registered, return EEXIST if the * same handler is registered, return 0 in case of success. */ @@ -28,30 +28,37 @@ int nf_register_queue_handler(int pf, struct nf_queue_handler *qh) if (pf >= NPROTO) return -EINVAL; - write_lock_bh(&queue_handler_lock); + mutex_lock(&queue_handler_mutex); if (queue_handler[pf] == qh) ret = -EEXIST; else if (queue_handler[pf]) ret = -EBUSY; else { - queue_handler[pf] = qh; + rcu_assign_pointer(queue_handler[pf], qh); ret = 0; } - write_unlock_bh(&queue_handler_lock); + mutex_unlock(&queue_handler_mutex); return ret; } EXPORT_SYMBOL(nf_register_queue_handler); /* The caller must flush their queue before this */ -int nf_unregister_queue_handler(int pf) +int nf_unregister_queue_handler(int pf, struct nf_queue_handler *qh) { if (pf >= NPROTO) return -EINVAL; - write_lock_bh(&queue_handler_lock); - queue_handler[pf] = NULL; - write_unlock_bh(&queue_handler_lock); + mutex_lock(&queue_handler_mutex); + if (queue_handler[pf] != qh) { + mutex_unlock(&queue_handler_mutex); + return -EINVAL; + } + + rcu_assign_pointer(queue_handler[pf], NULL); + mutex_unlock(&queue_handler_mutex); + + synchronize_rcu(); return 0; } @@ -61,12 +68,14 @@ void nf_unregister_queue_handlers(struct nf_queue_handler *qh) { int pf; - write_lock_bh(&queue_handler_lock); + mutex_lock(&queue_handler_mutex); for (pf = 0; pf < NPROTO; pf++) { if (queue_handler[pf] == qh) - queue_handler[pf] = NULL; + rcu_assign_pointer(queue_handler[pf], NULL); } - write_unlock_bh(&queue_handler_lock); + mutex_unlock(&queue_handler_mutex); + + synchronize_rcu(); } EXPORT_SYMBOL_GPL(nf_unregister_queue_handlers); @@ -89,18 +98,21 @@ static int __nf_queue(struct sk_buff *skb, struct net_device *physoutdev = NULL; #endif struct nf_afinfo *afinfo; + struct nf_queue_handler *qh; /* QUEUE == DROP if noone is waiting, to be safe. */ - read_lock(&queue_handler_lock); - if (!queue_handler[pf]) { - read_unlock(&queue_handler_lock); + rcu_read_lock(); + + qh = rcu_dereference(queue_handler[pf]); + if (!qh) { + rcu_read_unlock(); kfree_skb(skb); return 1; } afinfo = nf_get_afinfo(pf); if (!afinfo) { - read_unlock(&queue_handler_lock); + rcu_read_unlock(); kfree_skb(skb); return 1; } @@ -110,7 +122,7 @@ static int __nf_queue(struct sk_buff *skb, if (net_ratelimit()) printk(KERN_ERR "OOM queueing packet %p\n", skb); - read_unlock(&queue_handler_lock); + rcu_read_unlock(); kfree_skb(skb); return 1; } @@ -120,7 +132,7 @@ static int __nf_queue(struct sk_buff *skb, /* If it's going away, ignore hook. */ if (!try_module_get(info->elem->owner)) { - read_unlock(&queue_handler_lock); + rcu_read_unlock(); kfree(info); return 0; } @@ -138,10 +150,9 @@ static int __nf_queue(struct sk_buff *skb, } #endif afinfo->saveroute(skb, info); - status = queue_handler[pf]->outfn(skb, info, queuenum, - queue_handler[pf]->data); + status = qh->outfn(skb, info, queuenum, qh->data); - read_unlock(&queue_handler_lock); + rcu_read_unlock(); if (status < 0) { /* James M doesn't say fuck enough. */ @@ -308,18 +319,18 @@ static int seq_show(struct seq_file *s, void *v) loff_t *pos = v; struct nf_queue_handler *qh; - read_lock_bh(&queue_handler_lock); - qh = queue_handler[*pos]; + rcu_read_lock(); + qh = rcu_dereference(queue_handler[*pos]); if (!qh) ret = seq_printf(s, "%2lld NONE\n", *pos); else ret = seq_printf(s, "%2lld %s\n", *pos, qh->name); - read_unlock_bh(&queue_handler_lock); + rcu_read_unlock(); return ret; } -static struct seq_operations nfqueue_seq_ops = { +static const struct seq_operations nfqueue_seq_ops = { .start = seq_start, .next = seq_next, .stop = seq_stop, |