netfilter: core: remove synchronize_net call if nfqueue is used

since commit 960632ece6949b ("netfilter: convert hook list to an array")
nfqueue no longer stores a pointer to the hook that caused the packet
to be queued.  Therefore no extra synchronize_net() call is needed after
dropping the packets enqueued by the old rule blob.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/include/net/netfilter/nf_queue.h b/include/net/netfilter/nf_queue.h
index 814058d..a50a69f 100644 (file)
--- a/include/net/netfilter/nf_queue.h
+++ b/include/net/netfilter/nf_queue.h
@@ -25,7 +25,7 @@ struct nf_queue_entry {
 struct nf_queue_handler {
        int             (*outfn)(struct nf_queue_entry *entry,
                                 unsigned int queuenum);
-       unsigned int    (*nf_hook_drop)(struct net *net);
+       void            (*nf_hook_drop)(struct net *net);
 };
 
 void nf_register_queue_handler(struct net *net, const struct nf_queue_handler *qh);

diff --git a/net/netfilter/core.c b/net/netfilter/core.c
index d39bb2c..9a84b6c 100644 (file)
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@ -341,7 +341,6 @@ void nf_unregister_net_hook(struct net *net, const struct nf_hook_ops *reg)
 {
        struct nf_hook_entries __rcu **pp;
        struct nf_hook_entries *p;
-       unsigned int nfq;
 
        pp = nf_hook_entry_head(net, reg);
        if (!pp)
@@ -364,10 +363,7 @@ void nf_unregister_net_hook(struct net *net, const struct nf_hook_ops *reg)
 
        synchronize_net();
 
-       /* other cpu might still process nfqueue verdict that used reg */
-       nfq = nf_queue_nf_hook_drop(net);
-       if (nfq)
-               synchronize_net();
+       nf_queue_nf_hook_drop(net);
        kvfree(p);
 }
 EXPORT_SYMBOL(nf_unregister_net_hook);

diff --git a/net/netfilter/nf_internals.h b/net/netfilter/nf_internals.h
index 44284cd..18f6d7a 100644 (file)
--- a/net/netfilter/nf_internals.h
+++ b/net/netfilter/nf_internals.h
@@ -10,7 +10,7 @@
 int nf_queue(struct sk_buff *skb, struct nf_hook_state *state,
             const struct nf_hook_entries *entries, unsigned int index,
             unsigned int verdict);
-unsigned int nf_queue_nf_hook_drop(struct net *net);
+void nf_queue_nf_hook_drop(struct net *net);
 
 /* nf_log.c */
 int __init netfilter_log_init(void);

diff --git a/net/netfilter/nf_queue.c b/net/netfilter/nf_queue.c
index f7e2195..4e42a4a 100644 (file)
--- a/net/netfilter/nf_queue.c
+++ b/net/netfilter/nf_queue.c
@@ -96,18 +96,15 @@ void nf_queue_entry_get_refs(struct nf_queue_entry *entry)
 }
 EXPORT_SYMBOL_GPL(nf_queue_entry_get_refs);
 
-unsigned int nf_queue_nf_hook_drop(struct net *net)
+void nf_queue_nf_hook_drop(struct net *net)
 {
        const struct nf_queue_handler *qh;
-       unsigned int count = 0;
 
        rcu_read_lock();
        qh = rcu_dereference(net->nf.queue_handler);
        if (qh)
-               count = qh->nf_hook_drop(net);
+               qh->nf_hook_drop(net);
        rcu_read_unlock();
-
-       return count;
 }
 EXPORT_SYMBOL_GPL(nf_queue_nf_hook_drop);
 

diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index c09b367..2db35f2 100644 (file)
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -941,23 +941,18 @@ static struct notifier_block nfqnl_dev_notifier = {
        .notifier_call  = nfqnl_rcv_dev_event,
 };
 
-static unsigned int nfqnl_nf_hook_drop(struct net *net)
+static void nfqnl_nf_hook_drop(struct net *net)
 {
        struct nfnl_queue_net *q = nfnl_queue_pernet(net);
-       unsigned int instances = 0;
        int i;
 
        for (i = 0; i < INSTANCE_BUCKETS; i++) {
                struct nfqnl_instance *inst;
                struct hlist_head *head = &q->instance_table[i];
 
-               hlist_for_each_entry_rcu(inst, head, hlist) {
+               hlist_for_each_entry_rcu(inst, head, hlist)
                        nfqnl_flush(inst, NULL, 0);
-                       instances++;
-               }
        }
-
-       return instances;
 }
 
 static int