h = __nf_conntrack_find(net, tuple);
if (h) {
ct = nf_ct_tuplehash_to_ctrack(h);
- if (unlikely(!atomic_inc_not_zero(&ct->ct_general.use)))
+ if (unlikely(nf_ct_is_dying(ct) ||
+ !atomic_inc_not_zero(&ct->ct_general.use)))
h = NULL;
else {
if (unlikely(!nf_ct_tuple_equal(tuple, &h->tuple))) {
/* Remove from unconfirmed list */
hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode);
- __nf_conntrack_hash_insert(ct, hash, repl_hash);
/* Timer relative to confirmation time, not original
setting time, otherwise we'd get timer wrap in
weird delay cases. */
add_timer(&ct->timeout);
atomic_inc(&ct->ct_general.use);
set_bit(IPS_CONFIRMED_BIT, &ct->status);
+
+ /* Since the lookup is lockless, hash insertion must be done after
+ * starting the timer and setting the CONFIRMED bit. The RCU barriers
+ * guarantee that no other CPU can find the conntrack before the above
+ * stores are visible.
+ */
+ __nf_conntrack_hash_insert(ct, hash, repl_hash);
NF_CT_STAT_INC(net, insert);
spin_unlock_bh(&nf_conntrack_lock);
+
help = nfct_help(ct);
if (help && help->helper)
nf_conntrack_event_cache(IPCT_HELPER, ct);
cnt++;
}
- if (ct && unlikely(!atomic_inc_not_zero(&ct->ct_general.use)))
+ if (ct && unlikely(nf_ct_is_dying(ct) ||
+ !atomic_inc_not_zero(&ct->ct_general.use)))
ct = NULL;
if (ct || cnt >= NF_CT_EVICTION_RANGE)
break;
return ret;
}
+/*
+ * We need to use special "null" values, not used in hash table
+ */
+#define UNCONFIRMED_NULLS_VAL ((1<<30)+0)
+#define DYING_NULLS_VAL ((1<<30)+1)
+
static int nf_conntrack_init_net(struct net *net)
{
int ret;
atomic_set(&net->ct.count, 0);
- INIT_HLIST_NULLS_HEAD(&net->ct.unconfirmed, 0);
- INIT_HLIST_NULLS_HEAD(&net->ct.dying, 0);
+ INIT_HLIST_NULLS_HEAD(&net->ct.unconfirmed, UNCONFIRMED_NULLS_VAL);
+ INIT_HLIST_NULLS_HEAD(&net->ct.dying, DYING_NULLS_VAL);
net->ct.stat = alloc_percpu(struct ip_conntrack_stat);
if (!net->ct.stat) {
ret = -ENOMEM;