gre: fix netns vs proto registration ordering
[safe/jmp/linux-2.6] / net / ipv4 / udp.c
index 4274c1c..608a544 100644 (file)
@@ -136,33 +136,67 @@ static int udp_lib_lport_inuse(struct net *net, __u16 num,
        struct hlist_nulls_node *node;
 
        sk_nulls_for_each(sk2, node, &hslot->head)
-               if (net_eq(sock_net(sk2), net)                  &&
-                   sk2 != sk                                   &&
-                   (bitmap || sk2->sk_hash == num)             &&
-                   (!sk2->sk_reuse || !sk->sk_reuse)           &&
-                   (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if
-                       || sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
+               if (net_eq(sock_net(sk2), net) &&
+                   sk2 != sk &&
+                   (bitmap || udp_sk(sk2)->udp_port_hash == num) &&
+                   (!sk2->sk_reuse || !sk->sk_reuse) &&
+                   (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
+                    sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
                    (*saddr_comp)(sk, sk2)) {
                        if (bitmap)
-                               __set_bit(sk2->sk_hash >> log, bitmap);
+                               __set_bit(udp_sk(sk2)->udp_port_hash >> log,
+                                         bitmap);
                        else
                                return 1;
                }
        return 0;
 }
 
+/*
+ * Note: we still hold spinlock of primary hash chain, so no other writer
+ * can insert/delete a socket with local_port == num
+ */
+static int udp_lib_lport_inuse2(struct net *net, __u16 num,
+                              struct udp_hslot *hslot2,
+                              struct sock *sk,
+                              int (*saddr_comp)(const struct sock *sk1,
+                                                const struct sock *sk2))
+{
+       struct sock *sk2;
+       struct hlist_nulls_node *node;
+       int res = 0;
+
+       spin_lock(&hslot2->lock);
+       udp_portaddr_for_each_entry(sk2, node, &hslot2->head)
+               if (net_eq(sock_net(sk2), net) &&
+                   sk2 != sk &&
+                   (udp_sk(sk2)->udp_port_hash == num) &&
+                   (!sk2->sk_reuse || !sk->sk_reuse) &&
+                   (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
+                    sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
+                   (*saddr_comp)(sk, sk2)) {
+                       res = 1;
+                       break;
+               }
+       spin_unlock(&hslot2->lock);
+       return res;
+}
+
 /**
  *  udp_lib_get_port  -  UDP/-Lite port lookup for IPv4 and IPv6
  *
  *  @sk:          socket struct in question
  *  @snum:        port number to look up
  *  @saddr_comp:  AF-dependent comparison of bound local IP addresses
+ *  @hash2_nulladdr: AF-dependant hash value in secondary hash chains,
+ *                   with NULL address
  */
 int udp_lib_get_port(struct sock *sk, unsigned short snum,
                       int (*saddr_comp)(const struct sock *sk1,
-                                        const struct sock *sk2))
+                                        const struct sock *sk2),
+                    unsigned int hash2_nulladdr)
 {
-       struct udp_hslot *hslot;
+       struct udp_hslot *hslot, *hslot2;
        struct udp_table *udptable = sk->sk_prot->h.udp_table;
        int    error = 1;
        struct net *net = sock_net(sk);
@@ -182,9 +216,8 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum,
                 * force rand to be an odd multiple of UDP_HTABLE_SIZE
                 */
                rand = (rand | 1) * (udptable->mask + 1);
-               for (last = first + udptable->mask + 1;
-                    first != last;
-                    first++) {
+               last = first + udptable->mask + 1;
+               do {
                        hslot = udp_hashslot(udptable, net, first);
                        bitmap_zero(bitmap, PORTS_PER_CHAIN);
                        spin_lock_bh(&hslot->lock);
@@ -204,21 +237,54 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum,
                                snum += rand;
                        } while (snum != first);
                        spin_unlock_bh(&hslot->lock);
-               }
+               } while (++first != last);
                goto fail;
        } else {
                hslot = udp_hashslot(udptable, net, snum);
                spin_lock_bh(&hslot->lock);
+               if (hslot->count > 10) {
+                       int exist;
+                       unsigned int slot2 = udp_sk(sk)->udp_portaddr_hash ^ snum;
+
+                       slot2          &= udptable->mask;
+                       hash2_nulladdr &= udptable->mask;
+
+                       hslot2 = udp_hashslot2(udptable, slot2);
+                       if (hslot->count < hslot2->count)
+                               goto scan_primary_hash;
+
+                       exist = udp_lib_lport_inuse2(net, snum, hslot2,
+                                                    sk, saddr_comp);
+                       if (!exist && (hash2_nulladdr != slot2)) {
+                               hslot2 = udp_hashslot2(udptable, hash2_nulladdr);
+                               exist = udp_lib_lport_inuse2(net, snum, hslot2,
+                                                            sk, saddr_comp);
+                       }
+                       if (exist)
+                               goto fail_unlock;
+                       else
+                               goto found;
+               }
+scan_primary_hash:
                if (udp_lib_lport_inuse(net, snum, hslot, NULL, sk,
                                        saddr_comp, 0))
                        goto fail_unlock;
        }
 found:
        inet_sk(sk)->inet_num = snum;
-       sk->sk_hash = snum;
+       udp_sk(sk)->udp_port_hash = snum;
+       udp_sk(sk)->udp_portaddr_hash ^= snum;
        if (sk_unhashed(sk)) {
                sk_nulls_add_node_rcu(sk, &hslot->head);
+               hslot->count++;
                sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
+
+               hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
+               spin_lock(&hslot2->lock);
+               hlist_nulls_add_head_rcu(&udp_sk(sk)->udp_portaddr_node,
+                                        &hslot2->head);
+               hslot2->count++;
+               spin_unlock(&hslot2->lock);
        }
        error = 0;
 fail_unlock:
@@ -237,9 +303,22 @@ static int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2)
                   inet1->inet_rcv_saddr == inet2->inet_rcv_saddr));
 }
 
+static unsigned int udp4_portaddr_hash(struct net *net, __be32 saddr,
+                                      unsigned int port)
+{
+       return jhash_1word(saddr, net_hash_mix(net)) ^ port;
+}
+
 int udp_v4_get_port(struct sock *sk, unsigned short snum)
 {
-       return udp_lib_get_port(sk, snum, ipv4_rcv_saddr_equal);
+       unsigned int hash2_nulladdr =
+               udp4_portaddr_hash(sock_net(sk), INADDR_ANY, snum);
+       unsigned int hash2_partial =
+               udp4_portaddr_hash(sock_net(sk), inet_sk(sk)->inet_rcv_saddr, 0);
+
+       /* precompute partial secondary hash */
+       udp_sk(sk)->udp_portaddr_hash = hash2_partial;
+       return udp_lib_get_port(sk, snum, ipv4_rcv_saddr_equal, hash2_nulladdr);
 }
 
 static inline int compute_score(struct sock *sk, struct net *net, __be32 saddr,
@@ -248,7 +327,7 @@ static inline int compute_score(struct sock *sk, struct net *net, __be32 saddr,
 {
        int score = -1;
 
-       if (net_eq(sock_net(sk), net) && sk->sk_hash == hnum &&
+       if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
                        !ipv6_only_sock(sk)) {
                struct inet_sock *inet = inet_sk(sk);
 
@@ -277,6 +356,89 @@ static inline int compute_score(struct sock *sk, struct net *net, __be32 saddr,
        return score;
 }
 
+/*
+ * In this second variant, we check (daddr, dport) matches (inet_rcv_sadd, inet_num)
+ */
+#define SCORE2_MAX (1 + 2 + 2 + 2)
+static inline int compute_score2(struct sock *sk, struct net *net,
+                                __be32 saddr, __be16 sport,
+                                __be32 daddr, unsigned int hnum, int dif)
+{
+       int score = -1;
+
+       if (net_eq(sock_net(sk), net) && !ipv6_only_sock(sk)) {
+               struct inet_sock *inet = inet_sk(sk);
+
+               if (inet->inet_rcv_saddr != daddr)
+                       return -1;
+               if (inet->inet_num != hnum)
+                       return -1;
+
+               score = (sk->sk_family == PF_INET ? 1 : 0);
+               if (inet->inet_daddr) {
+                       if (inet->inet_daddr != saddr)
+                               return -1;
+                       score += 2;
+               }
+               if (inet->inet_dport) {
+                       if (inet->inet_dport != sport)
+                               return -1;
+                       score += 2;
+               }
+               if (sk->sk_bound_dev_if) {
+                       if (sk->sk_bound_dev_if != dif)
+                               return -1;
+                       score += 2;
+               }
+       }
+       return score;
+}
+
+
+/* called with read_rcu_lock() */
+static struct sock *udp4_lib_lookup2(struct net *net,
+               __be32 saddr, __be16 sport,
+               __be32 daddr, unsigned int hnum, int dif,
+               struct udp_hslot *hslot2, unsigned int slot2)
+{
+       struct sock *sk, *result;
+       struct hlist_nulls_node *node;
+       int score, badness;
+
+begin:
+       result = NULL;
+       badness = -1;
+       udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
+               score = compute_score2(sk, net, saddr, sport,
+                                     daddr, hnum, dif);
+               if (score > badness) {
+                       result = sk;
+                       badness = score;
+                       if (score == SCORE2_MAX)
+                               goto exact_match;
+               }
+       }
+       /*
+        * if the nulls value we got at the end of this lookup is
+        * not the expected one, we must restart lookup.
+        * We probably met an item that was moved to another chain.
+        */
+       if (get_nulls_value(node) != slot2)
+               goto begin;
+
+       if (result) {
+exact_match:
+               if (unlikely(!atomic_inc_not_zero(&result->sk_refcnt)))
+                       result = NULL;
+               else if (unlikely(compute_score2(result, net, saddr, sport,
+                                 daddr, hnum, dif) < badness)) {
+                       sock_put(result);
+                       goto begin;
+               }
+       }
+       return result;
+}
+
 /* UDP is nearly always wildcards out the wazoo, it makes no sense to try
  * harder than this. -DaveM
  */
@@ -287,11 +449,35 @@ static struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
        struct sock *sk, *result;
        struct hlist_nulls_node *node;
        unsigned short hnum = ntohs(dport);
-       unsigned int hash = udp_hashfn(net, hnum, udptable->mask);
-       struct udp_hslot *hslot = &udptable->hash[hash];
+       unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
+       struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
        int score, badness;
 
        rcu_read_lock();
+       if (hslot->count > 10) {
+               hash2 = udp4_portaddr_hash(net, daddr, hnum);
+               slot2 = hash2 & udptable->mask;
+               hslot2 = &udptable->hash2[slot2];
+               if (hslot->count < hslot2->count)
+                       goto begin;
+
+               result = udp4_lib_lookup2(net, saddr, sport,
+                                         daddr, hnum, dif,
+                                         hslot2, slot2);
+               if (!result) {
+                       hash2 = udp4_portaddr_hash(net, INADDR_ANY, hnum);
+                       slot2 = hash2 & udptable->mask;
+                       hslot2 = &udptable->hash2[slot2];
+                       if (hslot->count < hslot2->count)
+                               goto begin;
+
+                       result = udp4_lib_lookup2(net, INADDR_ANY, sport,
+                                                 daddr, hnum, dif,
+                                                 hslot2, slot2);
+               }
+               rcu_read_unlock();
+               return result;
+       }
 begin:
        result = NULL;
        badness = -1;
@@ -308,7 +494,7 @@ begin:
         * not the expected one, we must restart lookup.
         * We probably met an item that was moved to another chain.
         */
-       if (get_nulls_value(node) != hash)
+       if (get_nulls_value(node) != slot)
                goto begin;
 
        if (result) {
@@ -358,13 +544,13 @@ static inline struct sock *udp_v4_mcast_next(struct net *net, struct sock *sk,
        sk_nulls_for_each_from(s, node) {
                struct inet_sock *inet = inet_sk(s);
 
-               if (!net_eq(sock_net(s), net)                           ||
-                   s->sk_hash != hnum                                  ||
-                   (inet->inet_daddr && inet->inet_daddr != rmt_addr)  ||
-                   (inet->inet_dport != rmt_port && inet->inet_dport)  ||
-                   (inet->inet_rcv_saddr       &&
-                    inet->inet_rcv_saddr != loc_addr)                  ||
-                   ipv6_only_sock(s)                                   ||
+               if (!net_eq(sock_net(s), net) ||
+                   udp_sk(s)->udp_port_hash != hnum ||
+                   (inet->inet_daddr && inet->inet_daddr != rmt_addr) ||
+                   (inet->inet_dport != rmt_port && inet->inet_dport) ||
+                   (inet->inet_rcv_saddr &&
+                    inet->inet_rcv_saddr != loc_addr) ||
+                   ipv6_only_sock(s) ||
                    (s->sk_bound_dev_if && s->sk_bound_dev_if != dif))
                        continue;
                if (!ip_mc_sf_allow(s, loc_addr, rmt_addr, dif))
@@ -931,7 +1117,7 @@ int udp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
        struct inet_sock *inet = inet_sk(sk);
        struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
        struct sk_buff *skb;
-       unsigned int ulen, copied;
+       unsigned int ulen;
        int peeked;
        int err;
        int is_udplite = IS_UDPLITE(sk);
@@ -952,10 +1138,9 @@ try_again:
                goto out;
 
        ulen = skb->len - sizeof(struct udphdr);
-       copied = len;
-       if (copied > ulen)
-               copied = ulen;
-       else if (copied < ulen)
+       if (len > ulen)
+               len = ulen;
+       else if (len < ulen)
                msg->msg_flags |= MSG_TRUNC;
 
        /*
@@ -964,14 +1149,14 @@ try_again:
         * coverage checksum (UDP-Lite), do it before the copy.
         */
 
-       if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
+       if (len < ulen || UDP_SKB_CB(skb)->partial_cov) {
                if (udp_lib_checksum_complete(skb))
                        goto csum_copy_err;
        }
 
        if (skb_csum_unnecessary(skb))
                err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr),
-                                             msg->msg_iov, copied);
+                                             msg->msg_iov, len);
        else {
                err = skb_copy_and_csum_datagram_iovec(skb,
                                                       sizeof(struct udphdr),
@@ -1000,14 +1185,12 @@ try_again:
        if (inet->cmsg_flags)
                ip_cmsg_recv(msg, skb);
 
-       err = copied;
+       err = len;
        if (flags & MSG_TRUNC)
                err = ulen;
 
 out_free:
-       lock_sock(sk);
-       skb_free_datagram(sk, skb);
-       release_sock(sk);
+       skb_free_datagram_locked(sk, skb);
 out:
        return err;
 
@@ -1050,13 +1233,22 @@ void udp_lib_unhash(struct sock *sk)
 {
        if (sk_hashed(sk)) {
                struct udp_table *udptable = sk->sk_prot->h.udp_table;
-               struct udp_hslot *hslot = udp_hashslot(udptable, sock_net(sk),
-                                                    sk->sk_hash);
+               struct udp_hslot *hslot, *hslot2;
+
+               hslot  = udp_hashslot(udptable, sock_net(sk),
+                                     udp_sk(sk)->udp_port_hash);
+               hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
 
                spin_lock_bh(&hslot->lock);
                if (sk_nulls_del_node_init_rcu(sk)) {
+                       hslot->count--;
                        inet_sk(sk)->inet_num = 0;
                        sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
+
+                       spin_lock(&hslot2->lock);
+                       hlist_nulls_del_init_rcu(&udp_sk(sk)->udp_portaddr_node);
+                       hslot2->count--;
+                       spin_unlock(&hslot2->lock);
                }
                spin_unlock_bh(&hslot->lock);
        }
@@ -1192,49 +1384,83 @@ drop:
        return -1;
 }
 
+
+static void flush_stack(struct sock **stack, unsigned int count,
+                       struct sk_buff *skb, unsigned int final)
+{
+       unsigned int i;
+       struct sk_buff *skb1 = NULL;
+       struct sock *sk;
+
+       for (i = 0; i < count; i++) {
+               sk = stack[i];
+               if (likely(skb1 == NULL))
+                       skb1 = (i == final) ? skb : skb_clone(skb, GFP_ATOMIC);
+
+               if (!skb1) {
+                       atomic_inc(&sk->sk_drops);
+                       UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_RCVBUFERRORS,
+                                        IS_UDPLITE(sk));
+                       UDP_INC_STATS_BH(sock_net(sk), UDP_MIB_INERRORS,
+                                        IS_UDPLITE(sk));
+               }
+
+               if (skb1 && udp_queue_rcv_skb(sk, skb1) <= 0)
+                       skb1 = NULL;
+       }
+       if (unlikely(skb1))
+               kfree_skb(skb1);
+}
+
 /*
  *     Multicasts and broadcasts go to each listener.
  *
- *     Note: called only from the BH handler context,
- *     so we don't need to lock the hashes.
+ *     Note: called only from the BH handler context.
  */
 static int __udp4_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
                                    struct udphdr  *uh,
                                    __be32 saddr, __be32 daddr,
                                    struct udp_table *udptable)
 {
-       struct sock *sk;
+       struct sock *sk, *stack[256 / sizeof(struct sock *)];
        struct udp_hslot *hslot = udp_hashslot(udptable, net, ntohs(uh->dest));
        int dif;
+       unsigned int i, count = 0;
 
        spin_lock(&hslot->lock);
        sk = sk_nulls_head(&hslot->head);
        dif = skb->dev->ifindex;
        sk = udp_v4_mcast_next(net, sk, uh->dest, daddr, uh->source, saddr, dif);
-       if (sk) {
-               struct sock *sknext = NULL;
+       while (sk) {
+               stack[count++] = sk;
+               sk = udp_v4_mcast_next(net, sk_nulls_next(sk), uh->dest,
+                                      daddr, uh->source, saddr, dif);
+               if (unlikely(count == ARRAY_SIZE(stack))) {
+                       if (!sk)
+                               break;
+                       flush_stack(stack, count, skb, ~0);
+                       count = 0;
+               }
+       }
+       /*
+        * before releasing chain lock, we must take a reference on sockets
+        */
+       for (i = 0; i < count; i++)
+               sock_hold(stack[i]);
 
-               do {
-                       struct sk_buff *skb1 = skb;
-
-                       sknext = udp_v4_mcast_next(net, sk_nulls_next(sk), uh->dest,
-                                                  daddr, uh->source, saddr,
-                                                  dif);
-                       if (sknext)
-                               skb1 = skb_clone(skb, GFP_ATOMIC);
-
-                       if (skb1) {
-                               int ret = udp_queue_rcv_skb(sk, skb1);
-                               if (ret > 0)
-                                       /* we should probably re-process instead
-                                        * of dropping packets here. */
-                                       kfree_skb(skb1);
-                       }
-                       sk = sknext;
-               } while (sknext);
-       } else
-               consume_skb(skb);
        spin_unlock(&hslot->lock);
+
+       /*
+        * do the slow work with no lock held
+        */
+       if (count) {
+               flush_stack(stack, count, skb, count - 1);
+
+               for (i = 0; i < count; i++)
+                       sock_put(stack[i]);
+       } else {
+               kfree_skb(skb);
+       }
        return 0;
 }
 
@@ -1800,12 +2026,12 @@ static struct udp_seq_afinfo udp4_seq_afinfo = {
        },
 };
 
-static int udp4_proc_init_net(struct net *net)
+static int __net_init udp4_proc_init_net(struct net *net)
 {
        return udp_proc_register(net, &udp4_seq_afinfo);
 }
 
-static void udp4_proc_exit_net(struct net *net)
+static void __net_exit udp4_proc_exit_net(struct net *net)
 {
        udp_proc_unregister(net, &udp4_seq_afinfo);
 }
@@ -1844,7 +2070,7 @@ void __init udp_table_init(struct udp_table *table, const char *name)
 
        if (!CONFIG_BASE_SMALL)
                table->hash = alloc_large_system_hash(name,
-                       sizeof(struct udp_hslot),
+                       2 * sizeof(struct udp_hslot),
                        uhash_entries,
                        21, /* one slot per 2 MB */
                        0,
@@ -1856,16 +2082,23 @@ void __init udp_table_init(struct udp_table *table, const char *name)
         */
        if (CONFIG_BASE_SMALL || table->mask < UDP_HTABLE_SIZE_MIN - 1) {
                table->hash = kmalloc(UDP_HTABLE_SIZE_MIN *
-                                     sizeof(struct udp_hslot), GFP_KERNEL);
+                                     2 * sizeof(struct udp_hslot), GFP_KERNEL);
                if (!table->hash)
                        panic(name);
                table->log = ilog2(UDP_HTABLE_SIZE_MIN);
                table->mask = UDP_HTABLE_SIZE_MIN - 1;
        }
+       table->hash2 = table->hash + (table->mask + 1);
        for (i = 0; i <= table->mask; i++) {
                INIT_HLIST_NULLS_HEAD(&table->hash[i].head, i);
+               table->hash[i].count = 0;
                spin_lock_init(&table->hash[i].lock);
        }
+       for (i = 0; i <= table->mask; i++) {
+               INIT_HLIST_NULLS_HEAD(&table->hash2[i].head, i);
+               table->hash2[i].count = 0;
+               spin_lock_init(&table->hash2[i].lock);
+       }
 }
 
 void __init udp_init(void)