diff options
Diffstat (limited to 'net/netfilter/nf_conntrack_core.c')
-rw-r--r-- | net/netfilter/nf_conntrack_core.c | 42 |
1 files changed, 35 insertions, 7 deletions
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index da2650f872e1..94e18fb9690d 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -77,6 +77,8 @@ static __read_mostly bool nf_conntrack_locks_all; #define GC_SCAN_INTERVAL (120u * HZ) #define GC_SCAN_MAX_DURATION msecs_to_jiffies(10) +#define MAX_CHAINLEN 64u + static struct conntrack_gc_work conntrack_gc_work; void nf_conntrack_lock(spinlock_t *lock) __acquires(lock) @@ -840,7 +842,9 @@ nf_conntrack_hash_check_insert(struct nf_conn *ct) unsigned int hash, reply_hash; struct nf_conntrack_tuple_hash *h; struct hlist_nulls_node *n; + unsigned int chainlen = 0; unsigned int sequence; + int err = -EEXIST; zone = nf_ct_zone(ct); @@ -854,15 +858,24 @@ nf_conntrack_hash_check_insert(struct nf_conn *ct) } while (nf_conntrack_double_lock(net, hash, reply_hash, sequence)); /* See if there's one in the list already, including reverse */ - hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[hash], hnnode) + hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[hash], hnnode) { if (nf_ct_key_equal(h, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, zone, net)) goto out; - hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[reply_hash], hnnode) + if (chainlen++ > MAX_CHAINLEN) + goto chaintoolong; + } + + chainlen = 0; + + hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[reply_hash], hnnode) { if (nf_ct_key_equal(h, &ct->tuplehash[IP_CT_DIR_REPLY].tuple, zone, net)) goto out; + if (chainlen++ > MAX_CHAINLEN) + goto chaintoolong; + } smp_wmb(); /* The caller holds a reference to this object */ @@ -872,11 +885,13 @@ nf_conntrack_hash_check_insert(struct nf_conn *ct) NF_CT_STAT_INC(net, insert); local_bh_enable(); return 0; - +chaintoolong: + NF_CT_STAT_INC(net, chaintoolong); + err = -ENOSPC; out: nf_conntrack_double_unlock(hash, reply_hash); local_bh_enable(); - return -EEXIST; + return err; } EXPORT_SYMBOL_GPL(nf_conntrack_hash_check_insert); @@ -1089,6 +1104,7 @@ int __nf_conntrack_confirm(struct sk_buff *skb) { const struct nf_conntrack_zone *zone; + unsigned int chainlen = 0, sequence; unsigned int hash, reply_hash; struct nf_conntrack_tuple_hash *h; struct nf_conn *ct; @@ -1096,7 +1112,6 @@ __nf_conntrack_confirm(struct sk_buff *skb) struct hlist_nulls_node *n; enum ip_conntrack_info ctinfo; struct net *net; - unsigned int sequence; int ret = NF_DROP; ct = nf_ct_get(skb, &ctinfo); @@ -1156,15 +1171,28 @@ __nf_conntrack_confirm(struct sk_buff *skb) /* See if there's one in the list already, including reverse: NAT could have grabbed it without realizing, since we're not in the hash. If there is, we lost race. */ - hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[hash], hnnode) + hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[hash], hnnode) { if (nf_ct_key_equal(h, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple, zone, net)) goto out; + if (chainlen++ > MAX_CHAINLEN) + goto chaintoolong; + } - hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[reply_hash], hnnode) + chainlen = 0; + hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[reply_hash], hnnode) { if (nf_ct_key_equal(h, &ct->tuplehash[IP_CT_DIR_REPLY].tuple, zone, net)) goto out; + if (chainlen++ > MAX_CHAINLEN) { +chaintoolong: + nf_ct_add_to_dying_list(ct); + NF_CT_STAT_INC(net, chaintoolong); + NF_CT_STAT_INC(net, insert_failed); + ret = NF_DROP; + goto dying; + } + } /* Timer relative to confirmation time, not original setting time, otherwise we'd get timer wrap in |