2.6.25-rc7

 net

 netlink

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index de3988b..1ab0da2 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -156,7 +156,7 @@ static void netlink_sock_destruct(struct sock *sk)
    skb_queue_purge(&sk->sk_receive_queue);
 
    if (!sock_flag(sk, SOCK_DEAD)) {
-      printk("Freeing alive netlink socket %p\n", sk);
+      printk(KERN_ERR "Freeing alive netlink socket %p\n", sk);
       return;
    }
    BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc));
@@ -164,13 +164,14 @@ static void netlink_sock_destruct(struct sock *sk)
    BUG_TRAP(!nlk_sk(sk)->groups);
 }
 
-/* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on SMP.
- * Look, when several writers sleep and reader wakes them up, all but one
+/* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on
+ * SMP. Look, when several writers sleep and reader wakes them up, all but one
  * immediately hit write lock and grab all the cpus. Exclusive sleep solves
  * this, _but_ remember, it adds useless work on UP machines.
  */
 
 static void netlink_table_grab(void)
+   __acquires(nl_table_lock)
 {
    write_lock_irq(&nl_table_lock);
 
@@ -178,7 +179,7 @@ static void netlink_table_grab(void)
       DECLARE_WAITQUEUE(wait, current);
 
       add_wait_queue_exclusive(&nl_table_wait, &wait);
-      for(;;) {
+      for (;;) {
          set_current_state(TASK_UNINTERRUPTIBLE);
          if (atomic_read(&nl_table_users) == 0)
             break;
@@ -192,13 +193,14 @@ static void netlink_table_grab(void)
    }
 }
 
-static __inline__ void netlink_table_ungrab(void)
+static void netlink_table_ungrab(void)
+   __releases(nl_table_lock)
 {
    write_unlock_irq(&nl_table_lock);
    wake_up(&nl_table_wait);
 }
 
-static __inline__ void
+static inline void
 netlink_lock_table(void)
 {
    /* read_lock() synchronizes us to netlink_table_grab */
@@ -208,14 +210,15 @@ netlink_lock_table(void)
    read_unlock(&nl_table_lock);
 }
 
-static __inline__ void
+static inline void
 netlink_unlock_table(void)
 {
    if (atomic_dec_and_test(&nl_table_users))
       wake_up(&nl_table_wait);
 }
 
-static __inline__ struct sock *netlink_lookup(struct net *net, int protocol, u32 pid)
+static inline struct sock *netlink_lookup(struct net *net, int protocol,
+                 u32 pid)
 {
    struct nl_pid_hash *hash = &nl_table[protocol].hash;
    struct hlist_head *head;
@@ -236,13 +239,14 @@ found:
    return sk;
 }
 
-static inline struct hlist_head *nl_pid_hash_alloc(size_t size)
+static inline struct hlist_head *nl_pid_hash_zalloc(size_t size)
 {
    if (size <= PAGE_SIZE)
-      return kmalloc(size, GFP_ATOMIC);
+      return kzalloc(size, GFP_ATOMIC);
    else
       return (struct hlist_head *)
-         __get_free_pages(GFP_ATOMIC, get_order(size));
+         __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
+                get_order(size));
 }
 
 static inline void nl_pid_hash_free(struct hlist_head *table, size_t size)
@@ -271,11 +275,10 @@ static int nl_pid_hash_rehash(struct nl_pid_hash *hash, int grow)
       size *= 2;
    }
 
-   table = nl_pid_hash_alloc(size);
+   table = nl_pid_hash_zalloc(size);
    if (!table)
       return 0;
 
-   memset(table, 0, size);
    otable = hash->table;
    hash->table = table;
    hash->mask = mask;
@@ -428,7 +431,7 @@ static int netlink_create(struct net *net, struct socket *sock, int protocol)
    if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
       return -ESOCKTNOSUPPORT;
 
-   if (protocol<0 || protocol >= MAX_LINKS)
+   if (protocol < 0 || protocol >= MAX_LINKS)
       return -EPROTONOSUPPORT;
 
    netlink_lock_table();
@@ -445,7 +448,8 @@ static int netlink_create(struct net *net, struct socket *sock, int protocol)
    cb_mutex = nl_table[protocol].cb_mutex;
    netlink_unlock_table();
 
-   if ((err = __netlink_create(net, sock, cb_mutex, protocol)) < 0)
+   err = __netlink_create(net, sock, cb_mutex, protocol);
+   if (err < 0)
       goto out_module;
 
    nlk = nlk_sk(sock->sk);
@@ -494,9 +498,12 @@ static int netlink_release(struct socket *sock)
 
    netlink_table_grab();
    if (netlink_is_kernel(sk)) {
-      kfree(nl_table[sk->sk_protocol].listeners);
-      nl_table[sk->sk_protocol].module = NULL;
-      nl_table[sk->sk_protocol].registered = 0;
+      BUG_ON(nl_table[sk->sk_protocol].registered == 0);
+      if (--nl_table[sk->sk_protocol].registered == 0) {
+         kfree(nl_table[sk->sk_protocol].listeners);
+         nl_table[sk->sk_protocol].module = NULL;
+         nl_table[sk->sk_protocol].registered = 0;
+      }
    } else if (nlk->subscriptions)
       netlink_update_listeners(sk);
    netlink_table_ungrab();
@@ -590,7 +597,7 @@ static int netlink_realloc_groups(struct sock *sk)
       err = -ENOMEM;
       goto out_unlock;
    }
-   memset((char*)new_groups + NLGRPSZ(nlk->ngroups), 0,
+   memset((char *)new_groups + NLGRPSZ(nlk->ngroups), 0,
           NLGRPSZ(groups) - NLGRPSZ(nlk->ngroups));
 
    nlk->groups = new_groups;
@@ -600,7 +607,8 @@ static int netlink_realloc_groups(struct sock *sk)
    return err;
 }
 
-static int netlink_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
+static int netlink_bind(struct socket *sock, struct sockaddr *addr,
+         int addr_len)
 {
    struct sock *sk = sock->sk;
    struct net *net = sk->sk_net;
@@ -651,7 +659,7 @@ static int netlink_connect(struct socket *sock, struct sockaddr *addr,
    int err = 0;
    struct sock *sk = sock->sk;
    struct netlink_sock *nlk = nlk_sk(sk);
-   struct sockaddr_nl *nladdr=(struct sockaddr_nl*)addr;
+   struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
 
    if (addr->sa_family == AF_UNSPEC) {
       sk->sk_state   = NETLINK_UNCONNECTED;
@@ -678,11 +686,12 @@ static int netlink_connect(struct socket *sock, struct sockaddr *addr,
    return err;
 }
 
-static int netlink_getname(struct socket *sock, struct sockaddr *addr, int *addr_len, int peer)
+static int netlink_getname(struct socket *sock, struct sockaddr *addr,
+            int *addr_len, int peer)
 {
    struct sock *sk = sock->sk;
    struct netlink_sock *nlk = nlk_sk(sk);
-   struct sockaddr_nl *nladdr=(struct sockaddr_nl *)addr;
+   struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
 
    nladdr->nl_family = AF_NETLINK;
    nladdr->nl_pad = 0;
@@ -885,6 +894,7 @@ retry:
 
    return netlink_sendskb(sk, skb);
 }
+EXPORT_SYMBOL(netlink_unicast);
 
 int netlink_has_listeners(struct sock *sk, unsigned int group)
 {
@@ -905,7 +915,8 @@ int netlink_has_listeners(struct sock *sk, unsigned int group)
 }
 EXPORT_SYMBOL_GPL(netlink_has_listeners);
 
-static __inline__ int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb)
+static inline int netlink_broadcast_deliver(struct sock *sk,
+                   struct sk_buff *skb)
 {
    struct netlink_sock *nlk = nlk_sk(sk);
 
@@ -1026,6 +1037,7 @@ int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 pid,
       return -ENOBUFS;
    return -ESRCH;
 }
+EXPORT_SYMBOL(netlink_broadcast);
 
 struct netlink_set_err_data {
    struct sock *exclude_sk;
@@ -1182,7 +1194,7 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
    struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
    struct sock *sk = sock->sk;
    struct netlink_sock *nlk = nlk_sk(sk);
-   struct sockaddr_nl *addr=msg->msg_name;
+   struct sockaddr_nl *addr = msg->msg_name;
    u32 dst_pid;
    u32 dst_group;
    struct sk_buff *skb;
@@ -1221,12 +1233,12 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
       goto out;
    err = -ENOBUFS;
    skb = alloc_skb(len, GFP_KERNEL);
-   if (skb==NULL)
+   if (skb == NULL)
       goto out;
 
    NETLINK_CB(skb).pid   = nlk->pid;
    NETLINK_CB(skb).dst_group = dst_group;
-   NETLINK_CB(skb).loginuid = audit_get_loginuid(current->audit_context);
+   NETLINK_CB(skb).loginuid = audit_get_loginuid(current);
    selinux_get_task_sid(current, &(NETLINK_CB(skb).sid));
    memcpy(NETLINK_CREDS(skb), &siocb->scm->creds, sizeof(struct ucred));
 
@@ -1237,7 +1249,7 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
     */
 
    err = -EFAULT;
-   if (memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len)) {
+   if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
       kfree_skb(skb);
       goto out;
    }
@@ -1276,8 +1288,8 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
 
    copied = 0;
 
-   skb = skb_recv_datagram(sk,flags,noblock,&err);
-   if (skb==NULL)
+   skb = skb_recv_datagram(sk, flags, noblock, &err);
+   if (skb == NULL)
       goto out;
 
    msg->msg_namelen = 0;
@@ -1292,7 +1304,7 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
    err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 
    if (msg->msg_name) {
-      struct sockaddr_nl *addr = (struct sockaddr_nl*)msg->msg_name;
+      struct sockaddr_nl *addr = (struct sockaddr_nl *)msg->msg_name;
       addr->nl_family = AF_NETLINK;
       addr->nl_pad    = 0;
       addr->nl_pid   = NETLINK_CB(skb).pid;
@@ -1332,6 +1344,22 @@ static void netlink_data_ready(struct sock *sk, int len)
  *   queueing.
  */
 
+static void __netlink_release(struct sock *sk)
+{
+   /*
+    * Last sock_put should drop referrence to sk->sk_net. It has already
+    * been dropped in netlink_kernel_create. Taking referrence to stopping
+    * namespace is not an option.
+    * Take referrence to a socket to remove it from netlink lookup table
+    * _alive_ and after that destroy it in the context of init_net.
+    */
+
+   sock_hold(sk);
+   sock_release(sk->sk_socket);
+   sk->sk_net = get_net(&init_net);
+   sock_put(sk);
+}
+
 struct sock *
 netlink_kernel_create(struct net *net, int unit, unsigned int groups,
             void (*input)(struct sk_buff *skb),
@@ -1344,14 +1372,24 @@ netlink_kernel_create(struct net *net, int unit, unsigned int groups,
 
    BUG_ON(!nl_table);
 
-   if (unit<0 || unit>=MAX_LINKS)
+   if (unit < 0 || unit >= MAX_LINKS)
       return NULL;
 
    if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock))
       return NULL;
 
-   if (__netlink_create(net, sock, cb_mutex, unit) < 0)
-      goto out_sock_release;
+   /*
+    * We have to just have a reference on the net from sk, but don't
+    * get_net it. Besides, we cannot get and then put the net here.
+    * So we create one inside init_net and the move it to net.
+    */
+
+   if (__netlink_create(&init_net, sock, cb_mutex, unit) < 0)
+      goto out_sock_release_nosk;
+
+   sk = sock->sk;
+   put_net(sk->sk_net);
+   sk->sk_net = net;
 
    if (groups < 32)
       groups = 32;
@@ -1360,7 +1398,6 @@ netlink_kernel_create(struct net *net, int unit, unsigned int groups,
    if (!listeners)
       goto out_sock_release;
 
-   sk = sock->sk;
    sk->sk_data_ready = netlink_data_ready;
    if (input)
       nlk_sk(sk)->netlink_rcv = input;
@@ -1380,16 +1417,33 @@ netlink_kernel_create(struct net *net, int unit, unsigned int groups,
       nl_table[unit].registered = 1;
    } else {
       kfree(listeners);
+      nl_table[unit].registered++;
    }
    netlink_table_ungrab();
-
    return sk;
 
 out_sock_release:
    kfree(listeners);
+   __netlink_release(sk);
+   return NULL;
+
+out_sock_release_nosk:
    sock_release(sock);
    return NULL;
 }
+EXPORT_SYMBOL(netlink_kernel_create);
+
+
+void
+netlink_kernel_release(struct sock *sk)
+{
+   if (sk == NULL || sk->sk_socket == NULL)
+      return;
+
+   __netlink_release(sk);
+}
+EXPORT_SYMBOL(netlink_kernel_release);
+
 
 /**
  * netlink_change_ngroups - change number of multicast groups
@@ -1461,6 +1515,7 @@ void netlink_set_nonroot(int protocol, unsigned int flags)
    if ((unsigned int)protocol < MAX_LINKS)
       nl_table[protocol].nl_nonroot = flags;
 }
+EXPORT_SYMBOL(netlink_set_nonroot);
 
 static void netlink_destroy_callback(struct netlink_callback *cb)
 {
@@ -1529,8 +1584,9 @@ errout:
 
 int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
              struct nlmsghdr *nlh,
-             int (*dump)(struct sk_buff *skb, struct netlink_callback*),
-             int (*done)(struct netlink_callback*))
+             int (*dump)(struct sk_buff *skb,
+               struct netlink_callback *),
+             int (*done)(struct netlink_callback *))
 {
    struct netlink_callback *cb;
    struct sock *sk;
@@ -1571,6 +1627,7 @@ int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
     */
    return -EINTR;
 }
+EXPORT_SYMBOL(netlink_dump_start);
 
 void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err)
 {
@@ -1605,6 +1662,7 @@ void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err)
    memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(*nlh));
    netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).pid, MSG_DONTWAIT);
 }
+EXPORT_SYMBOL(netlink_ack);
 
 int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *,
                        struct nlmsghdr *))
@@ -1638,7 +1696,7 @@ ack:
          netlink_ack(skb, nlh, err);
 
 skip:
-           msglen = NLMSG_ALIGN(nlh->nlmsg_len);
+      msglen = NLMSG_ALIGN(nlh->nlmsg_len);
       if (msglen > skb->len)
          msglen = skb->len;
       skb_pull(skb, msglen);
@@ -1646,6 +1704,7 @@ skip:
 
    return 0;
 }
+EXPORT_SYMBOL(netlink_rcv_skb);
 
 /**
  * nlmsg_notify - send a notification netlink message
@@ -1678,10 +1737,11 @@ int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 pid,
 
    return err;
 }
+EXPORT_SYMBOL(nlmsg_notify);
 
 #ifdef CONFIG_PROC_FS
 struct nl_seq_iter {
-   struct net *net;
+   struct seq_net_private p;
    int link;
    int hash_idx;
 };
@@ -1694,12 +1754,12 @@ static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos)
    struct hlist_node *node;
    loff_t off = 0;
 
-   for (i=0; i<MAX_LINKS; i++) {
+   for (i = 0; i < MAX_LINKS; i++) {
       struct nl_pid_hash *hash = &nl_table[i].hash;
 
       for (j = 0; j <= hash->mask; j++) {
          sk_for_each(s, node, &hash->table[j]) {
-            if (iter->net != s->sk_net)
+            if (iter->p.net != s->sk_net)
                continue;
             if (off == pos) {
                iter->link = i;
@@ -1714,6 +1774,7 @@ static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos)
 }
 
 static void *netlink_seq_start(struct seq_file *seq, loff_t *pos)
+   __acquires(nl_table_lock)
 {
    read_lock(&nl_table_lock);
    return *pos ? netlink_seq_socket_idx(seq, *pos - 1) : SEQ_START_TOKEN;
@@ -1734,7 +1795,7 @@ static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos)
    s = v;
    do {
       s = sk_next(s);
-   } while (s && (iter->net != s->sk_net));
+   } while (s && (iter->p.net != s->sk_net));
    if (s)
       return s;
 
@@ -1746,7 +1807,7 @@ static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 
       for (; j <= hash->mask; j++) {
          s = sk_head(&hash->table[j]);
-         while (s && (iter->net != s->sk_net))
+         while (s && (iter->p.net != s->sk_net))
             s = sk_next(s);
          if (s) {
             iter->link = i;
@@ -1762,6 +1823,7 @@ static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 }
 
 static void netlink_seq_stop(struct seq_file *seq, void *v)
+   __releases(nl_table_lock)
 {
    read_unlock(&nl_table_lock);
 }
@@ -1802,27 +1864,8 @@ static const struct seq_operations netlink_seq_ops = {
 
 static int netlink_seq_open(struct inode *inode, struct file *file)
 {
-   struct nl_seq_iter *iter;
-
-   iter = __seq_open_private(file, &netlink_seq_ops, sizeof(*iter));
-   if (!iter)
-      return -ENOMEM;
-
-   iter->net = get_proc_net(inode);
-   if (!iter->net) {
-      seq_release_private(inode, file);
-      return -ENXIO;
-   }
-
-   return 0;
-}
-
-static int netlink_seq_release(struct inode *inode, struct file *file)
-{
-   struct seq_file *seq = file->private_data;
-   struct nl_seq_iter *iter = seq->private;
-   put_net(iter->net);
-   return seq_release_private(inode, file);
+   return seq_open_net(inode, file, &netlink_seq_ops,
+            sizeof(struct nl_seq_iter));
 }
 
 static const struct file_operations netlink_seq_fops = {
@@ -1830,7 +1873,7 @@ static const struct file_operations netlink_seq_fops = {
    .open      = netlink_seq_open,
    .read      = seq_read,
    .llseek      = seq_lseek,
-   .release   = netlink_seq_release,
+   .release   = seq_release_net,
 };
 
 #endif
@@ -1839,11 +1882,13 @@ int netlink_register_notifier(struct notifier_block *nb)
 {
    return atomic_notifier_chain_register(&netlink_chain, nb);
 }
+EXPORT_SYMBOL(netlink_register_notifier);
 
 int netlink_unregister_notifier(struct notifier_block *nb)
 {
    return atomic_notifier_chain_unregister(&netlink_chain, nb);
 }
+EXPORT_SYMBOL(netlink_unregister_notifier);
 
 static const struct proto_ops netlink_ops = {
    .family =   PF_NETLINK,
@@ -1922,7 +1967,7 @@ static int __init netlink_proto_init(void)
    for (i = 0; i < MAX_LINKS; i++) {
       struct nl_pid_hash *hash = &nl_table[i].hash;
 
-      hash->table = nl_pid_hash_alloc(1 * sizeof(*hash->table));
+      hash->table = nl_pid_hash_zalloc(1 * sizeof(*hash->table));
       if (!hash->table) {
          while (i-- > 0)
             nl_pid_hash_free(nl_table[i].hash.table,
@@ -1930,7 +1975,6 @@ static int __init netlink_proto_init(void)
          kfree(nl_table);
          goto panic;
       }
-      memset(hash->table, 0, 1 * sizeof(*hash->table));
       hash->max_shift = order;
       hash->shift = 0;
       hash->mask = 0;
@@ -1948,14 +1992,3 @@ panic:
 }
 
 core_initcall(netlink_proto_init);
-
-EXPORT_SYMBOL(netlink_ack);
-EXPORT_SYMBOL(netlink_rcv_skb);
-EXPORT_SYMBOL(netlink_broadcast);
-EXPORT_SYMBOL(netlink_dump_start);
-EXPORT_SYMBOL(netlink_kernel_create);
-EXPORT_SYMBOL(netlink_register_notifier);
-EXPORT_SYMBOL(netlink_set_nonroot);
-EXPORT_SYMBOL(netlink_unicast);
-EXPORT_SYMBOL(netlink_unregister_notifier);
-EXPORT_SYMBOL(nlmsg_notify);