mac80211: fix another race in aggregation start
[linux-2.6.git] / net / netfilter / xt_connlimit.c
index e029c48..c6d5a83 100644 (file)
 
 /* we will save the tuples of all connections we care about */
 struct xt_connlimit_conn {
-       struct list_head list;
-       struct nf_conntrack_tuple tuple;
+       struct hlist_node               node;
+       struct nf_conntrack_tuple       tuple;
+       union nf_inet_addr              addr;
 };
 
 struct xt_connlimit_data {
-       struct list_head iphash[256];
-       spinlock_t lock;
+       struct hlist_head       iphash[256];
+       spinlock_t              lock;
 };
 
 static u_int32_t connlimit_rnd __read_mostly;
-static bool connlimit_rnd_inited __read_mostly;
 
 static inline unsigned int connlimit_iphash(__be32 addr)
 {
@@ -101,9 +101,9 @@ static int count_them(struct net *net,
 {
        const struct nf_conntrack_tuple_hash *found;
        struct xt_connlimit_conn *conn;
-       struct xt_connlimit_conn *tmp;
+       struct hlist_node *pos, *n;
        struct nf_conn *found_ct;
-       struct list_head *hash;
+       struct hlist_head *hash;
        bool addit = true;
        int matches = 0;
 
@@ -115,7 +115,7 @@ static int count_them(struct net *net,
        rcu_read_lock();
 
        /* check the saved connections */
-       list_for_each_entry_safe(conn, tmp, hash, list) {
+       hlist_for_each_entry_safe(conn, pos, n, hash, node) {
                found    = nf_conntrack_find_get(net, NF_CT_DEFAULT_ZONE,
                                                 &conn->tuple);
                found_ct = NULL;
@@ -135,7 +135,7 @@ static int count_them(struct net *net,
 
                if (found == NULL) {
                        /* this one is gone */
-                       list_del(&conn->list);
+                       hlist_del(&conn->node);
                        kfree(conn);
                        continue;
                }
@@ -146,12 +146,12 @@ static int count_them(struct net *net,
                         * closed already -> ditch it
                         */
                        nf_ct_put(found_ct);
-                       list_del(&conn->list);
+                       hlist_del(&conn->node);
                        kfree(conn);
                        continue;
                }
 
-               if (same_source_net(addr, mask, &conn->tuple.src.u3, family))
+               if (same_source_net(addr, mask, &conn->addr, family))
                        /* same source network -> be counted! */
                        ++matches;
                nf_ct_put(found_ct);
@@ -161,11 +161,12 @@ static int count_them(struct net *net,
 
        if (addit) {
                /* save the new connection in our list */
-               conn = kzalloc(sizeof(*conn), GFP_ATOMIC);
+               conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
                if (conn == NULL)
                        return -ENOMEM;
                conn->tuple = *tuple;
-               list_add(&conn->list, hash);
+               conn->addr = *addr;
+               hlist_add_head(&conn->node, hash);
                ++matches;
        }
 
@@ -185,15 +186,11 @@ connlimit_mt(const struct sk_buff *skb, struct xt_action_param *par)
        int connections;
 
        ct = nf_ct_get(skb, &ctinfo);
-       if (ct != NULL) {
-               if (info->flags & XT_CONNLIMIT_DADDR)
-                       tuple_ptr = &ct->tuplehash[IP_CT_DIR_REPLY].tuple;
-               else
-                       tuple_ptr = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
-       } else if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
-                                   par->family, &tuple)) {
+       if (ct != NULL)
+               tuple_ptr = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
+       else if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb),
+                                   par->family, &tuple))
                goto hotdrop;
-       }
 
        if (par->family == NFPROTO_IPV6) {
                const struct ipv6hdr *iph = ipv6_hdr(skb);
@@ -228,9 +225,13 @@ static int connlimit_mt_check(const struct xt_mtchk_param *par)
        unsigned int i;
        int ret;
 
-       if (unlikely(!connlimit_rnd_inited)) {
-               get_random_bytes(&connlimit_rnd, sizeof(connlimit_rnd));
-               connlimit_rnd_inited = true;
+       if (unlikely(!connlimit_rnd)) {
+               u_int32_t rand;
+
+               do {
+                       get_random_bytes(&rand, sizeof(rand));
+               } while (!rand);
+               cmpxchg(&connlimit_rnd, 0, rand);
        }
        ret = nf_ct_l3proto_try_module_get(par->family);
        if (ret < 0) {
@@ -248,7 +249,7 @@ static int connlimit_mt_check(const struct xt_mtchk_param *par)
 
        spin_lock_init(&info->data->lock);
        for (i = 0; i < ARRAY_SIZE(info->data->iphash); ++i)
-               INIT_LIST_HEAD(&info->data->iphash[i]);
+               INIT_HLIST_HEAD(&info->data->iphash[i]);
 
        return 0;
 }
@@ -257,15 +258,15 @@ static void connlimit_mt_destroy(const struct xt_mtdtor_param *par)
 {
        const struct xt_connlimit_info *info = par->matchinfo;
        struct xt_connlimit_conn *conn;
-       struct xt_connlimit_conn *tmp;
-       struct list_head *hash = info->data->iphash;
+       struct hlist_node *pos, *n;
+       struct hlist_head *hash = info->data->iphash;
        unsigned int i;
 
        nf_ct_l3proto_module_put(par->family);
 
        for (i = 0; i < ARRAY_SIZE(info->data->iphash); ++i) {
-               list_for_each_entry_safe(conn, tmp, &hash[i], list) {
-                       list_del(&conn->list);
+               hlist_for_each_entry_safe(conn, pos, n, &hash[i], node) {
+                       hlist_del(&conn->node);
                        kfree(conn);
                }
        }