gre: fix netns vs proto registration ordering
[safe/jmp/linux-2.6] / net / ipv4 / udp.c
index dd7f3d2..608a544 100644 (file)
@@ -136,12 +136,12 @@ 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                                   &&
+               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) &&
+                   (!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(udp_sk(sk2)->udp_port_hash >> log,
@@ -152,16 +152,49 @@ static int udp_lib_lport_inuse(struct net *net, __u16 num,
        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, *hslot2;
        struct udp_table *udptable = sk->sk_prot->h.udp_table;
@@ -183,9 +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);
@@ -205,11 +237,35 @@ 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;
@@ -255,12 +311,14 @@ static unsigned int udp4_portaddr_hash(struct net *net, __be32 saddr,
 
 int udp_v4_get_port(struct sock *sk, unsigned short snum)
 {
+       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 =
-               udp4_portaddr_hash(sock_net(sk),
-                                  inet_sk(sk)->inet_rcv_saddr,
-                                  0);
-       return udp_lib_get_port(sk, snum, ipv4_rcv_saddr_equal);
+       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,
@@ -336,8 +394,6 @@ static inline int compute_score2(struct sock *sk, struct net *net,
        return score;
 }
 
-#define udp_portaddr_for_each_entry_rcu(__sk, node, list) \
-       hlist_nulls_for_each_entry_rcu(__sk, node, list, __sk_common.skc_portaddr_node)
 
 /* called with read_rcu_lock() */
 static struct sock *udp4_lib_lookup2(struct net *net,
@@ -488,13 +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)                           ||
-                   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)                                   ||
+               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))
@@ -1061,7 +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);
@@ -1082,10 +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;
 
        /*
@@ -1094,14 +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),
@@ -1130,7 +1185,7 @@ try_again:
        if (inet->cmsg_flags)
                ip_cmsg_recv(msg, skb);
 
-       err = copied;
+       err = len;
        if (flags & MSG_TRUNC)
                err = ulen;
 
@@ -1329,49 +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;
 }
 
@@ -1937,12 +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);
 }