![David S. Miller](/assets/img/avatar_default.png)
1) netlink_release() should only decrement the hash entry count if the socket was actually hashed. This was causing hash->entries to underflow, which resulting in all kinds of troubles. On 64-bit systems, this would cause the following conditional to erroneously trigger: err = -ENOMEM; if (BITS_PER_LONG > 32 && unlikely(hash->entries >= UINT_MAX)) goto err; 2) netlink_autobind() needs to propagate the error return from netlink_insert(). Otherwise, callers will not see the error as they should and thus try to operate on a socket with a zero pid, which is very bad. However, it should not propagate -EBUSY. If two threads race to autobind the socket, that is fine. This is consistent with the autobind behavior in other protocols. So bug #1 above, combined with this one, resulted in hangs on netlink_sendmsg() calls to the rtnetlink socket. We'd try to do the user sendmsg() with the socket's pid set to zero, later we do a socket lookup using that pid (via the value we stashed away in NETLINK_CB(skb).pid), but that won't give us the user socket, it will give us the rtnetlink socket. So when we try to wake up the receive queue, we dive back into rtnetlink_rcv() which tries to recursively take the rtnetlink semaphore. Thanks to Jakub Jelink for providing backtraces. Also, thanks to Herbert Xu for supplying debugging patches to help track this down, and also finding a mistake in an earlier version of this fix. Signed-off-by: David S. Miller <davem@davemloft.net>
1466 lines
31 KiB
C
1466 lines
31 KiB
C
/*
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* NETLINK Kernel-user communication protocol.
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*
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* Authors: Alan Cox <alan@redhat.com>
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* Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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* Tue Jun 26 14:36:48 MEST 2001 Herbert "herp" Rosmanith
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* added netlink_proto_exit
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* Tue Jan 22 18:32:44 BRST 2002 Arnaldo C. de Melo <acme@conectiva.com.br>
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* use nlk_sk, as sk->protinfo is on a diet 8)
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*
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*/
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#include <linux/config.h>
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/signal.h>
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#include <linux/sched.h>
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#include <linux/errno.h>
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#include <linux/string.h>
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#include <linux/stat.h>
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#include <linux/socket.h>
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#include <linux/un.h>
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#include <linux/fcntl.h>
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#include <linux/termios.h>
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#include <linux/sockios.h>
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#include <linux/net.h>
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#include <linux/fs.h>
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#include <linux/slab.h>
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#include <asm/uaccess.h>
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#include <linux/skbuff.h>
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#include <linux/netdevice.h>
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#include <linux/rtnetlink.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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#include <linux/smp_lock.h>
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#include <linux/notifier.h>
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#include <linux/security.h>
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#include <linux/jhash.h>
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#include <linux/jiffies.h>
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#include <linux/random.h>
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#include <linux/bitops.h>
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#include <linux/mm.h>
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#include <linux/types.h>
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#include <linux/audit.h>
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#include <net/sock.h>
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#include <net/scm.h>
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#define Nprintk(a...)
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struct netlink_sock {
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/* struct sock has to be the first member of netlink_sock */
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struct sock sk;
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u32 pid;
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unsigned int groups;
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u32 dst_pid;
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unsigned int dst_groups;
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unsigned long state;
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wait_queue_head_t wait;
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struct netlink_callback *cb;
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spinlock_t cb_lock;
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void (*data_ready)(struct sock *sk, int bytes);
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};
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static inline struct netlink_sock *nlk_sk(struct sock *sk)
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{
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return (struct netlink_sock *)sk;
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}
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struct nl_pid_hash {
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struct hlist_head *table;
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unsigned long rehash_time;
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unsigned int mask;
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unsigned int shift;
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unsigned int entries;
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unsigned int max_shift;
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u32 rnd;
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};
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struct netlink_table {
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struct nl_pid_hash hash;
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struct hlist_head mc_list;
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unsigned int nl_nonroot;
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};
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static struct netlink_table *nl_table;
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static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait);
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static int netlink_dump(struct sock *sk);
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static void netlink_destroy_callback(struct netlink_callback *cb);
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static DEFINE_RWLOCK(nl_table_lock);
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static atomic_t nl_table_users = ATOMIC_INIT(0);
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static struct notifier_block *netlink_chain;
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static struct hlist_head *nl_pid_hashfn(struct nl_pid_hash *hash, u32 pid)
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{
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return &hash->table[jhash_1word(pid, hash->rnd) & hash->mask];
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}
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static void netlink_sock_destruct(struct sock *sk)
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{
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skb_queue_purge(&sk->sk_receive_queue);
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if (!sock_flag(sk, SOCK_DEAD)) {
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printk("Freeing alive netlink socket %p\n", sk);
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return;
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}
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BUG_TRAP(!atomic_read(&sk->sk_rmem_alloc));
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BUG_TRAP(!atomic_read(&sk->sk_wmem_alloc));
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BUG_TRAP(!nlk_sk(sk)->cb);
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}
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/* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on SMP.
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* Look, when several writers sleep and reader wakes them up, all but one
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* immediately hit write lock and grab all the cpus. Exclusive sleep solves
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* this, _but_ remember, it adds useless work on UP machines.
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*/
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static void netlink_table_grab(void)
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{
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write_lock_bh(&nl_table_lock);
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if (atomic_read(&nl_table_users)) {
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DECLARE_WAITQUEUE(wait, current);
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add_wait_queue_exclusive(&nl_table_wait, &wait);
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for(;;) {
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set_current_state(TASK_UNINTERRUPTIBLE);
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if (atomic_read(&nl_table_users) == 0)
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break;
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write_unlock_bh(&nl_table_lock);
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schedule();
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write_lock_bh(&nl_table_lock);
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}
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__set_current_state(TASK_RUNNING);
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remove_wait_queue(&nl_table_wait, &wait);
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}
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}
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static __inline__ void netlink_table_ungrab(void)
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{
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write_unlock_bh(&nl_table_lock);
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wake_up(&nl_table_wait);
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}
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static __inline__ void
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netlink_lock_table(void)
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{
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/* read_lock() synchronizes us to netlink_table_grab */
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read_lock(&nl_table_lock);
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atomic_inc(&nl_table_users);
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read_unlock(&nl_table_lock);
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}
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static __inline__ void
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netlink_unlock_table(void)
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{
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if (atomic_dec_and_test(&nl_table_users))
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wake_up(&nl_table_wait);
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}
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static __inline__ struct sock *netlink_lookup(int protocol, u32 pid)
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{
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struct nl_pid_hash *hash = &nl_table[protocol].hash;
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struct hlist_head *head;
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struct sock *sk;
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struct hlist_node *node;
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read_lock(&nl_table_lock);
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head = nl_pid_hashfn(hash, pid);
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sk_for_each(sk, node, head) {
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if (nlk_sk(sk)->pid == pid) {
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sock_hold(sk);
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goto found;
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}
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}
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sk = NULL;
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found:
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read_unlock(&nl_table_lock);
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return sk;
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}
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static inline struct hlist_head *nl_pid_hash_alloc(size_t size)
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{
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if (size <= PAGE_SIZE)
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return kmalloc(size, GFP_ATOMIC);
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else
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return (struct hlist_head *)
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__get_free_pages(GFP_ATOMIC, get_order(size));
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}
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static inline void nl_pid_hash_free(struct hlist_head *table, size_t size)
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{
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if (size <= PAGE_SIZE)
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kfree(table);
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else
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free_pages((unsigned long)table, get_order(size));
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}
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static int nl_pid_hash_rehash(struct nl_pid_hash *hash, int grow)
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{
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unsigned int omask, mask, shift;
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size_t osize, size;
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struct hlist_head *otable, *table;
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int i;
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omask = mask = hash->mask;
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osize = size = (mask + 1) * sizeof(*table);
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shift = hash->shift;
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if (grow) {
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if (++shift > hash->max_shift)
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return 0;
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mask = mask * 2 + 1;
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size *= 2;
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}
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table = nl_pid_hash_alloc(size);
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if (!table)
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return 0;
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memset(table, 0, size);
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otable = hash->table;
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hash->table = table;
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hash->mask = mask;
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hash->shift = shift;
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get_random_bytes(&hash->rnd, sizeof(hash->rnd));
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for (i = 0; i <= omask; i++) {
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struct sock *sk;
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struct hlist_node *node, *tmp;
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sk_for_each_safe(sk, node, tmp, &otable[i])
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__sk_add_node(sk, nl_pid_hashfn(hash, nlk_sk(sk)->pid));
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}
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nl_pid_hash_free(otable, osize);
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hash->rehash_time = jiffies + 10 * 60 * HZ;
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return 1;
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}
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static inline int nl_pid_hash_dilute(struct nl_pid_hash *hash, int len)
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{
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int avg = hash->entries >> hash->shift;
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if (unlikely(avg > 1) && nl_pid_hash_rehash(hash, 1))
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return 1;
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if (unlikely(len > avg) && time_after(jiffies, hash->rehash_time)) {
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nl_pid_hash_rehash(hash, 0);
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return 1;
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}
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return 0;
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}
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static struct proto_ops netlink_ops;
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static int netlink_insert(struct sock *sk, u32 pid)
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{
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struct nl_pid_hash *hash = &nl_table[sk->sk_protocol].hash;
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struct hlist_head *head;
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int err = -EADDRINUSE;
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struct sock *osk;
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struct hlist_node *node;
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int len;
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netlink_table_grab();
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head = nl_pid_hashfn(hash, pid);
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len = 0;
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sk_for_each(osk, node, head) {
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if (nlk_sk(osk)->pid == pid)
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break;
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len++;
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}
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if (node)
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goto err;
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err = -EBUSY;
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if (nlk_sk(sk)->pid)
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goto err;
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err = -ENOMEM;
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if (BITS_PER_LONG > 32 && unlikely(hash->entries >= UINT_MAX))
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goto err;
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if (len && nl_pid_hash_dilute(hash, len))
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head = nl_pid_hashfn(hash, pid);
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hash->entries++;
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nlk_sk(sk)->pid = pid;
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sk_add_node(sk, head);
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err = 0;
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err:
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netlink_table_ungrab();
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return err;
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}
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static void netlink_remove(struct sock *sk)
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{
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netlink_table_grab();
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if (sk_del_node_init(sk))
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nl_table[sk->sk_protocol].hash.entries--;
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if (nlk_sk(sk)->groups)
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__sk_del_bind_node(sk);
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netlink_table_ungrab();
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}
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static struct proto netlink_proto = {
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.name = "NETLINK",
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.owner = THIS_MODULE,
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.obj_size = sizeof(struct netlink_sock),
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};
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static int netlink_create(struct socket *sock, int protocol)
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{
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struct sock *sk;
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struct netlink_sock *nlk;
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sock->state = SS_UNCONNECTED;
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if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
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return -ESOCKTNOSUPPORT;
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if (protocol<0 || protocol >= MAX_LINKS)
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return -EPROTONOSUPPORT;
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sock->ops = &netlink_ops;
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sk = sk_alloc(PF_NETLINK, GFP_KERNEL, &netlink_proto, 1);
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if (!sk)
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return -ENOMEM;
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sock_init_data(sock, sk);
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nlk = nlk_sk(sk);
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spin_lock_init(&nlk->cb_lock);
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init_waitqueue_head(&nlk->wait);
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sk->sk_destruct = netlink_sock_destruct;
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sk->sk_protocol = protocol;
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return 0;
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}
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static int netlink_release(struct socket *sock)
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{
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struct sock *sk = sock->sk;
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struct netlink_sock *nlk;
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if (!sk)
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return 0;
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netlink_remove(sk);
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nlk = nlk_sk(sk);
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spin_lock(&nlk->cb_lock);
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if (nlk->cb) {
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nlk->cb->done(nlk->cb);
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netlink_destroy_callback(nlk->cb);
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nlk->cb = NULL;
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}
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spin_unlock(&nlk->cb_lock);
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/* OK. Socket is unlinked, and, therefore,
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no new packets will arrive */
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sock_orphan(sk);
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sock->sk = NULL;
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wake_up_interruptible_all(&nlk->wait);
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skb_queue_purge(&sk->sk_write_queue);
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if (nlk->pid && !nlk->groups) {
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struct netlink_notify n = {
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.protocol = sk->sk_protocol,
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.pid = nlk->pid,
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};
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notifier_call_chain(&netlink_chain, NETLINK_URELEASE, &n);
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}
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sock_put(sk);
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return 0;
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}
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static int netlink_autobind(struct socket *sock)
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{
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struct sock *sk = sock->sk;
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struct nl_pid_hash *hash = &nl_table[sk->sk_protocol].hash;
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struct hlist_head *head;
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struct sock *osk;
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struct hlist_node *node;
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s32 pid = current->pid;
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int err;
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static s32 rover = -4097;
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retry:
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cond_resched();
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netlink_table_grab();
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head = nl_pid_hashfn(hash, pid);
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sk_for_each(osk, node, head) {
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if (nlk_sk(osk)->pid == pid) {
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/* Bind collision, search negative pid values. */
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pid = rover--;
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if (rover > -4097)
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rover = -4097;
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netlink_table_ungrab();
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goto retry;
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}
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}
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netlink_table_ungrab();
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err = netlink_insert(sk, pid);
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if (err == -EADDRINUSE)
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goto retry;
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/* If 2 threads race to autobind, that is fine. */
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if (err == -EBUSY)
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err = 0;
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return err;
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}
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static inline int netlink_capable(struct socket *sock, unsigned int flag)
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{
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return (nl_table[sock->sk->sk_protocol].nl_nonroot & flag) ||
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capable(CAP_NET_ADMIN);
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}
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|
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static int netlink_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
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{
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struct sock *sk = sock->sk;
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struct netlink_sock *nlk = nlk_sk(sk);
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struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
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int err;
|
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|
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if (nladdr->nl_family != AF_NETLINK)
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return -EINVAL;
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|
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/* Only superuser is allowed to listen multicasts */
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if (nladdr->nl_groups && !netlink_capable(sock, NL_NONROOT_RECV))
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return -EPERM;
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|
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if (nlk->pid) {
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if (nladdr->nl_pid != nlk->pid)
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return -EINVAL;
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} else {
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err = nladdr->nl_pid ?
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netlink_insert(sk, nladdr->nl_pid) :
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netlink_autobind(sock);
|
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if (err)
|
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return err;
|
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}
|
|
|
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if (!nladdr->nl_groups && !nlk->groups)
|
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return 0;
|
|
|
|
netlink_table_grab();
|
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if (nlk->groups && !nladdr->nl_groups)
|
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__sk_del_bind_node(sk);
|
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else if (!nlk->groups && nladdr->nl_groups)
|
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sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list);
|
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nlk->groups = nladdr->nl_groups;
|
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netlink_table_ungrab();
|
|
|
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return 0;
|
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}
|
|
|
|
static int netlink_connect(struct socket *sock, struct sockaddr *addr,
|
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int alen, int flags)
|
|
{
|
|
int err = 0;
|
|
struct sock *sk = sock->sk;
|
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struct netlink_sock *nlk = nlk_sk(sk);
|
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struct sockaddr_nl *nladdr=(struct sockaddr_nl*)addr;
|
|
|
|
if (addr->sa_family == AF_UNSPEC) {
|
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sk->sk_state = NETLINK_UNCONNECTED;
|
|
nlk->dst_pid = 0;
|
|
nlk->dst_groups = 0;
|
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return 0;
|
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}
|
|
if (addr->sa_family != AF_NETLINK)
|
|
return -EINVAL;
|
|
|
|
/* Only superuser is allowed to send multicasts */
|
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if (nladdr->nl_groups && !netlink_capable(sock, NL_NONROOT_SEND))
|
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return -EPERM;
|
|
|
|
if (!nlk->pid)
|
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err = netlink_autobind(sock);
|
|
|
|
if (err == 0) {
|
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sk->sk_state = NETLINK_CONNECTED;
|
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nlk->dst_pid = nladdr->nl_pid;
|
|
nlk->dst_groups = nladdr->nl_groups;
|
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}
|
|
|
|
return err;
|
|
}
|
|
|
|
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;
|
|
|
|
nladdr->nl_family = AF_NETLINK;
|
|
nladdr->nl_pad = 0;
|
|
*addr_len = sizeof(*nladdr);
|
|
|
|
if (peer) {
|
|
nladdr->nl_pid = nlk->dst_pid;
|
|
nladdr->nl_groups = nlk->dst_groups;
|
|
} else {
|
|
nladdr->nl_pid = nlk->pid;
|
|
nladdr->nl_groups = nlk->groups;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void netlink_overrun(struct sock *sk)
|
|
{
|
|
if (!test_and_set_bit(0, &nlk_sk(sk)->state)) {
|
|
sk->sk_err = ENOBUFS;
|
|
sk->sk_error_report(sk);
|
|
}
|
|
}
|
|
|
|
static struct sock *netlink_getsockbypid(struct sock *ssk, u32 pid)
|
|
{
|
|
int protocol = ssk->sk_protocol;
|
|
struct sock *sock;
|
|
struct netlink_sock *nlk;
|
|
|
|
sock = netlink_lookup(protocol, pid);
|
|
if (!sock)
|
|
return ERR_PTR(-ECONNREFUSED);
|
|
|
|
/* Don't bother queuing skb if kernel socket has no input function */
|
|
nlk = nlk_sk(sock);
|
|
if ((nlk->pid == 0 && !nlk->data_ready) ||
|
|
(sock->sk_state == NETLINK_CONNECTED &&
|
|
nlk->dst_pid != nlk_sk(ssk)->pid)) {
|
|
sock_put(sock);
|
|
return ERR_PTR(-ECONNREFUSED);
|
|
}
|
|
return sock;
|
|
}
|
|
|
|
struct sock *netlink_getsockbyfilp(struct file *filp)
|
|
{
|
|
struct inode *inode = filp->f_dentry->d_inode;
|
|
struct sock *sock;
|
|
|
|
if (!S_ISSOCK(inode->i_mode))
|
|
return ERR_PTR(-ENOTSOCK);
|
|
|
|
sock = SOCKET_I(inode)->sk;
|
|
if (sock->sk_family != AF_NETLINK)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
sock_hold(sock);
|
|
return sock;
|
|
}
|
|
|
|
/*
|
|
* Attach a skb to a netlink socket.
|
|
* The caller must hold a reference to the destination socket. On error, the
|
|
* reference is dropped. The skb is not send to the destination, just all
|
|
* all error checks are performed and memory in the queue is reserved.
|
|
* Return values:
|
|
* < 0: error. skb freed, reference to sock dropped.
|
|
* 0: continue
|
|
* 1: repeat lookup - reference dropped while waiting for socket memory.
|
|
*/
|
|
int netlink_attachskb(struct sock *sk, struct sk_buff *skb, int nonblock, long timeo)
|
|
{
|
|
struct netlink_sock *nlk;
|
|
|
|
nlk = nlk_sk(sk);
|
|
|
|
if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
|
|
test_bit(0, &nlk->state)) {
|
|
DECLARE_WAITQUEUE(wait, current);
|
|
if (!timeo) {
|
|
if (!nlk->pid)
|
|
netlink_overrun(sk);
|
|
sock_put(sk);
|
|
kfree_skb(skb);
|
|
return -EAGAIN;
|
|
}
|
|
|
|
__set_current_state(TASK_INTERRUPTIBLE);
|
|
add_wait_queue(&nlk->wait, &wait);
|
|
|
|
if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
|
|
test_bit(0, &nlk->state)) &&
|
|
!sock_flag(sk, SOCK_DEAD))
|
|
timeo = schedule_timeout(timeo);
|
|
|
|
__set_current_state(TASK_RUNNING);
|
|
remove_wait_queue(&nlk->wait, &wait);
|
|
sock_put(sk);
|
|
|
|
if (signal_pending(current)) {
|
|
kfree_skb(skb);
|
|
return sock_intr_errno(timeo);
|
|
}
|
|
return 1;
|
|
}
|
|
skb_set_owner_r(skb, sk);
|
|
return 0;
|
|
}
|
|
|
|
int netlink_sendskb(struct sock *sk, struct sk_buff *skb, int protocol)
|
|
{
|
|
struct netlink_sock *nlk;
|
|
int len = skb->len;
|
|
|
|
nlk = nlk_sk(sk);
|
|
|
|
skb_queue_tail(&sk->sk_receive_queue, skb);
|
|
sk->sk_data_ready(sk, len);
|
|
sock_put(sk);
|
|
return len;
|
|
}
|
|
|
|
void netlink_detachskb(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
kfree_skb(skb);
|
|
sock_put(sk);
|
|
}
|
|
|
|
static inline struct sk_buff *netlink_trim(struct sk_buff *skb, int allocation)
|
|
{
|
|
int delta;
|
|
|
|
skb_orphan(skb);
|
|
|
|
delta = skb->end - skb->tail;
|
|
if (delta * 2 < skb->truesize)
|
|
return skb;
|
|
|
|
if (skb_shared(skb)) {
|
|
struct sk_buff *nskb = skb_clone(skb, allocation);
|
|
if (!nskb)
|
|
return skb;
|
|
kfree_skb(skb);
|
|
skb = nskb;
|
|
}
|
|
|
|
if (!pskb_expand_head(skb, 0, -delta, allocation))
|
|
skb->truesize -= delta;
|
|
|
|
return skb;
|
|
}
|
|
|
|
int netlink_unicast(struct sock *ssk, struct sk_buff *skb, u32 pid, int nonblock)
|
|
{
|
|
struct sock *sk;
|
|
int err;
|
|
long timeo;
|
|
|
|
skb = netlink_trim(skb, gfp_any());
|
|
|
|
timeo = sock_sndtimeo(ssk, nonblock);
|
|
retry:
|
|
sk = netlink_getsockbypid(ssk, pid);
|
|
if (IS_ERR(sk)) {
|
|
kfree_skb(skb);
|
|
return PTR_ERR(sk);
|
|
}
|
|
err = netlink_attachskb(sk, skb, nonblock, timeo);
|
|
if (err == 1)
|
|
goto retry;
|
|
if (err)
|
|
return err;
|
|
|
|
return netlink_sendskb(sk, skb, ssk->sk_protocol);
|
|
}
|
|
|
|
static __inline__ int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct netlink_sock *nlk = nlk_sk(sk);
|
|
|
|
if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf &&
|
|
!test_bit(0, &nlk->state)) {
|
|
skb_set_owner_r(skb, sk);
|
|
skb_queue_tail(&sk->sk_receive_queue, skb);
|
|
sk->sk_data_ready(sk, skb->len);
|
|
return atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
struct netlink_broadcast_data {
|
|
struct sock *exclude_sk;
|
|
u32 pid;
|
|
u32 group;
|
|
int failure;
|
|
int congested;
|
|
int delivered;
|
|
int allocation;
|
|
struct sk_buff *skb, *skb2;
|
|
};
|
|
|
|
static inline int do_one_broadcast(struct sock *sk,
|
|
struct netlink_broadcast_data *p)
|
|
{
|
|
struct netlink_sock *nlk = nlk_sk(sk);
|
|
int val;
|
|
|
|
if (p->exclude_sk == sk)
|
|
goto out;
|
|
|
|
if (nlk->pid == p->pid || !(nlk->groups & p->group))
|
|
goto out;
|
|
|
|
if (p->failure) {
|
|
netlink_overrun(sk);
|
|
goto out;
|
|
}
|
|
|
|
sock_hold(sk);
|
|
if (p->skb2 == NULL) {
|
|
if (skb_shared(p->skb)) {
|
|
p->skb2 = skb_clone(p->skb, p->allocation);
|
|
} else {
|
|
p->skb2 = skb_get(p->skb);
|
|
/*
|
|
* skb ownership may have been set when
|
|
* delivered to a previous socket.
|
|
*/
|
|
skb_orphan(p->skb2);
|
|
}
|
|
}
|
|
if (p->skb2 == NULL) {
|
|
netlink_overrun(sk);
|
|
/* Clone failed. Notify ALL listeners. */
|
|
p->failure = 1;
|
|
} else if ((val = netlink_broadcast_deliver(sk, p->skb2)) < 0) {
|
|
netlink_overrun(sk);
|
|
} else {
|
|
p->congested |= val;
|
|
p->delivered = 1;
|
|
p->skb2 = NULL;
|
|
}
|
|
sock_put(sk);
|
|
|
|
out:
|
|
return 0;
|
|
}
|
|
|
|
int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 pid,
|
|
u32 group, int allocation)
|
|
{
|
|
struct netlink_broadcast_data info;
|
|
struct hlist_node *node;
|
|
struct sock *sk;
|
|
|
|
skb = netlink_trim(skb, allocation);
|
|
|
|
info.exclude_sk = ssk;
|
|
info.pid = pid;
|
|
info.group = group;
|
|
info.failure = 0;
|
|
info.congested = 0;
|
|
info.delivered = 0;
|
|
info.allocation = allocation;
|
|
info.skb = skb;
|
|
info.skb2 = NULL;
|
|
|
|
/* While we sleep in clone, do not allow to change socket list */
|
|
|
|
netlink_lock_table();
|
|
|
|
sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
|
|
do_one_broadcast(sk, &info);
|
|
|
|
kfree_skb(skb);
|
|
|
|
netlink_unlock_table();
|
|
|
|
if (info.skb2)
|
|
kfree_skb(info.skb2);
|
|
|
|
if (info.delivered) {
|
|
if (info.congested && (allocation & __GFP_WAIT))
|
|
yield();
|
|
return 0;
|
|
}
|
|
if (info.failure)
|
|
return -ENOBUFS;
|
|
return -ESRCH;
|
|
}
|
|
|
|
struct netlink_set_err_data {
|
|
struct sock *exclude_sk;
|
|
u32 pid;
|
|
u32 group;
|
|
int code;
|
|
};
|
|
|
|
static inline int do_one_set_err(struct sock *sk,
|
|
struct netlink_set_err_data *p)
|
|
{
|
|
struct netlink_sock *nlk = nlk_sk(sk);
|
|
|
|
if (sk == p->exclude_sk)
|
|
goto out;
|
|
|
|
if (nlk->pid == p->pid || !(nlk->groups & p->group))
|
|
goto out;
|
|
|
|
sk->sk_err = p->code;
|
|
sk->sk_error_report(sk);
|
|
out:
|
|
return 0;
|
|
}
|
|
|
|
void netlink_set_err(struct sock *ssk, u32 pid, u32 group, int code)
|
|
{
|
|
struct netlink_set_err_data info;
|
|
struct hlist_node *node;
|
|
struct sock *sk;
|
|
|
|
info.exclude_sk = ssk;
|
|
info.pid = pid;
|
|
info.group = group;
|
|
info.code = code;
|
|
|
|
read_lock(&nl_table_lock);
|
|
|
|
sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
|
|
do_one_set_err(sk, &info);
|
|
|
|
read_unlock(&nl_table_lock);
|
|
}
|
|
|
|
static inline void netlink_rcv_wake(struct sock *sk)
|
|
{
|
|
struct netlink_sock *nlk = nlk_sk(sk);
|
|
|
|
if (!skb_queue_len(&sk->sk_receive_queue))
|
|
clear_bit(0, &nlk->state);
|
|
if (!test_bit(0, &nlk->state))
|
|
wake_up_interruptible(&nlk->wait);
|
|
}
|
|
|
|
static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
|
|
struct msghdr *msg, size_t len)
|
|
{
|
|
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;
|
|
u32 dst_pid;
|
|
u32 dst_groups;
|
|
struct sk_buff *skb;
|
|
int err;
|
|
struct scm_cookie scm;
|
|
|
|
if (msg->msg_flags&MSG_OOB)
|
|
return -EOPNOTSUPP;
|
|
|
|
if (NULL == siocb->scm)
|
|
siocb->scm = &scm;
|
|
err = scm_send(sock, msg, siocb->scm);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
if (msg->msg_namelen) {
|
|
if (addr->nl_family != AF_NETLINK)
|
|
return -EINVAL;
|
|
dst_pid = addr->nl_pid;
|
|
dst_groups = addr->nl_groups;
|
|
if (dst_groups && !netlink_capable(sock, NL_NONROOT_SEND))
|
|
return -EPERM;
|
|
} else {
|
|
dst_pid = nlk->dst_pid;
|
|
dst_groups = nlk->dst_groups;
|
|
}
|
|
|
|
if (!nlk->pid) {
|
|
err = netlink_autobind(sock);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
|
|
err = -EMSGSIZE;
|
|
if (len > sk->sk_sndbuf - 32)
|
|
goto out;
|
|
err = -ENOBUFS;
|
|
skb = alloc_skb(len, GFP_KERNEL);
|
|
if (skb==NULL)
|
|
goto out;
|
|
|
|
NETLINK_CB(skb).pid = nlk->pid;
|
|
NETLINK_CB(skb).groups = nlk->groups;
|
|
NETLINK_CB(skb).dst_pid = dst_pid;
|
|
NETLINK_CB(skb).dst_groups = dst_groups;
|
|
NETLINK_CB(skb).loginuid = audit_get_loginuid(current->audit_context);
|
|
memcpy(NETLINK_CREDS(skb), &siocb->scm->creds, sizeof(struct ucred));
|
|
|
|
/* What can I do? Netlink is asynchronous, so that
|
|
we will have to save current capabilities to
|
|
check them, when this message will be delivered
|
|
to corresponding kernel module. --ANK (980802)
|
|
*/
|
|
|
|
err = -EFAULT;
|
|
if (memcpy_fromiovec(skb_put(skb,len), msg->msg_iov, len)) {
|
|
kfree_skb(skb);
|
|
goto out;
|
|
}
|
|
|
|
err = security_netlink_send(sk, skb);
|
|
if (err) {
|
|
kfree_skb(skb);
|
|
goto out;
|
|
}
|
|
|
|
if (dst_groups) {
|
|
atomic_inc(&skb->users);
|
|
netlink_broadcast(sk, skb, dst_pid, dst_groups, GFP_KERNEL);
|
|
}
|
|
err = netlink_unicast(sk, skb, dst_pid, msg->msg_flags&MSG_DONTWAIT);
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
|
|
struct msghdr *msg, size_t len,
|
|
int flags)
|
|
{
|
|
struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
|
|
struct scm_cookie scm;
|
|
struct sock *sk = sock->sk;
|
|
struct netlink_sock *nlk = nlk_sk(sk);
|
|
int noblock = flags&MSG_DONTWAIT;
|
|
size_t copied;
|
|
struct sk_buff *skb;
|
|
int err;
|
|
|
|
if (flags&MSG_OOB)
|
|
return -EOPNOTSUPP;
|
|
|
|
copied = 0;
|
|
|
|
skb = skb_recv_datagram(sk,flags,noblock,&err);
|
|
if (skb==NULL)
|
|
goto out;
|
|
|
|
msg->msg_namelen = 0;
|
|
|
|
copied = skb->len;
|
|
if (len < copied) {
|
|
msg->msg_flags |= MSG_TRUNC;
|
|
copied = len;
|
|
}
|
|
|
|
skb->h.raw = skb->data;
|
|
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;
|
|
addr->nl_family = AF_NETLINK;
|
|
addr->nl_pad = 0;
|
|
addr->nl_pid = NETLINK_CB(skb).pid;
|
|
addr->nl_groups = NETLINK_CB(skb).dst_groups;
|
|
msg->msg_namelen = sizeof(*addr);
|
|
}
|
|
|
|
if (NULL == siocb->scm) {
|
|
memset(&scm, 0, sizeof(scm));
|
|
siocb->scm = &scm;
|
|
}
|
|
siocb->scm->creds = *NETLINK_CREDS(skb);
|
|
skb_free_datagram(sk, skb);
|
|
|
|
if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2)
|
|
netlink_dump(sk);
|
|
|
|
scm_recv(sock, msg, siocb->scm, flags);
|
|
|
|
out:
|
|
netlink_rcv_wake(sk);
|
|
return err ? : copied;
|
|
}
|
|
|
|
static void netlink_data_ready(struct sock *sk, int len)
|
|
{
|
|
struct netlink_sock *nlk = nlk_sk(sk);
|
|
|
|
if (nlk->data_ready)
|
|
nlk->data_ready(sk, len);
|
|
netlink_rcv_wake(sk);
|
|
}
|
|
|
|
/*
|
|
* We export these functions to other modules. They provide a
|
|
* complete set of kernel non-blocking support for message
|
|
* queueing.
|
|
*/
|
|
|
|
struct sock *
|
|
netlink_kernel_create(int unit, void (*input)(struct sock *sk, int len))
|
|
{
|
|
struct socket *sock;
|
|
struct sock *sk;
|
|
|
|
if (!nl_table)
|
|
return NULL;
|
|
|
|
if (unit<0 || unit>=MAX_LINKS)
|
|
return NULL;
|
|
|
|
if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock))
|
|
return NULL;
|
|
|
|
if (netlink_create(sock, unit) < 0) {
|
|
sock_release(sock);
|
|
return NULL;
|
|
}
|
|
sk = sock->sk;
|
|
sk->sk_data_ready = netlink_data_ready;
|
|
if (input)
|
|
nlk_sk(sk)->data_ready = input;
|
|
|
|
if (netlink_insert(sk, 0)) {
|
|
sock_release(sock);
|
|
return NULL;
|
|
}
|
|
return sk;
|
|
}
|
|
|
|
void netlink_set_nonroot(int protocol, unsigned int flags)
|
|
{
|
|
if ((unsigned int)protocol < MAX_LINKS)
|
|
nl_table[protocol].nl_nonroot = flags;
|
|
}
|
|
|
|
static void netlink_destroy_callback(struct netlink_callback *cb)
|
|
{
|
|
if (cb->skb)
|
|
kfree_skb(cb->skb);
|
|
kfree(cb);
|
|
}
|
|
|
|
/*
|
|
* It looks a bit ugly.
|
|
* It would be better to create kernel thread.
|
|
*/
|
|
|
|
static int netlink_dump(struct sock *sk)
|
|
{
|
|
struct netlink_sock *nlk = nlk_sk(sk);
|
|
struct netlink_callback *cb;
|
|
struct sk_buff *skb;
|
|
struct nlmsghdr *nlh;
|
|
int len;
|
|
|
|
skb = sock_rmalloc(sk, NLMSG_GOODSIZE, 0, GFP_KERNEL);
|
|
if (!skb)
|
|
return -ENOBUFS;
|
|
|
|
spin_lock(&nlk->cb_lock);
|
|
|
|
cb = nlk->cb;
|
|
if (cb == NULL) {
|
|
spin_unlock(&nlk->cb_lock);
|
|
kfree_skb(skb);
|
|
return -EINVAL;
|
|
}
|
|
|
|
len = cb->dump(skb, cb);
|
|
|
|
if (len > 0) {
|
|
spin_unlock(&nlk->cb_lock);
|
|
skb_queue_tail(&sk->sk_receive_queue, skb);
|
|
sk->sk_data_ready(sk, len);
|
|
return 0;
|
|
}
|
|
|
|
nlh = NLMSG_NEW_ANSWER(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI);
|
|
memcpy(NLMSG_DATA(nlh), &len, sizeof(len));
|
|
skb_queue_tail(&sk->sk_receive_queue, skb);
|
|
sk->sk_data_ready(sk, skb->len);
|
|
|
|
cb->done(cb);
|
|
nlk->cb = NULL;
|
|
spin_unlock(&nlk->cb_lock);
|
|
|
|
netlink_destroy_callback(cb);
|
|
return 0;
|
|
|
|
nlmsg_failure:
|
|
return -ENOBUFS;
|
|
}
|
|
|
|
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*))
|
|
{
|
|
struct netlink_callback *cb;
|
|
struct sock *sk;
|
|
struct netlink_sock *nlk;
|
|
|
|
cb = kmalloc(sizeof(*cb), GFP_KERNEL);
|
|
if (cb == NULL)
|
|
return -ENOBUFS;
|
|
|
|
memset(cb, 0, sizeof(*cb));
|
|
cb->dump = dump;
|
|
cb->done = done;
|
|
cb->nlh = nlh;
|
|
atomic_inc(&skb->users);
|
|
cb->skb = skb;
|
|
|
|
sk = netlink_lookup(ssk->sk_protocol, NETLINK_CB(skb).pid);
|
|
if (sk == NULL) {
|
|
netlink_destroy_callback(cb);
|
|
return -ECONNREFUSED;
|
|
}
|
|
nlk = nlk_sk(sk);
|
|
/* A dump is in progress... */
|
|
spin_lock(&nlk->cb_lock);
|
|
if (nlk->cb) {
|
|
spin_unlock(&nlk->cb_lock);
|
|
netlink_destroy_callback(cb);
|
|
sock_put(sk);
|
|
return -EBUSY;
|
|
}
|
|
nlk->cb = cb;
|
|
spin_unlock(&nlk->cb_lock);
|
|
|
|
netlink_dump(sk);
|
|
sock_put(sk);
|
|
return 0;
|
|
}
|
|
|
|
void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err)
|
|
{
|
|
struct sk_buff *skb;
|
|
struct nlmsghdr *rep;
|
|
struct nlmsgerr *errmsg;
|
|
int size;
|
|
|
|
if (err == 0)
|
|
size = NLMSG_SPACE(sizeof(struct nlmsgerr));
|
|
else
|
|
size = NLMSG_SPACE(4 + NLMSG_ALIGN(nlh->nlmsg_len));
|
|
|
|
skb = alloc_skb(size, GFP_KERNEL);
|
|
if (!skb) {
|
|
struct sock *sk;
|
|
|
|
sk = netlink_lookup(in_skb->sk->sk_protocol,
|
|
NETLINK_CB(in_skb).pid);
|
|
if (sk) {
|
|
sk->sk_err = ENOBUFS;
|
|
sk->sk_error_report(sk);
|
|
sock_put(sk);
|
|
}
|
|
return;
|
|
}
|
|
|
|
rep = __nlmsg_put(skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
|
|
NLMSG_ERROR, sizeof(struct nlmsgerr), 0);
|
|
errmsg = NLMSG_DATA(rep);
|
|
errmsg->error = err;
|
|
memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(struct nlmsghdr));
|
|
netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).pid, MSG_DONTWAIT);
|
|
}
|
|
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
struct nl_seq_iter {
|
|
int link;
|
|
int hash_idx;
|
|
};
|
|
|
|
static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos)
|
|
{
|
|
struct nl_seq_iter *iter = seq->private;
|
|
int i, j;
|
|
struct sock *s;
|
|
struct hlist_node *node;
|
|
loff_t off = 0;
|
|
|
|
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 (off == pos) {
|
|
iter->link = i;
|
|
iter->hash_idx = j;
|
|
return s;
|
|
}
|
|
++off;
|
|
}
|
|
}
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
static void *netlink_seq_start(struct seq_file *seq, loff_t *pos)
|
|
{
|
|
read_lock(&nl_table_lock);
|
|
return *pos ? netlink_seq_socket_idx(seq, *pos - 1) : SEQ_START_TOKEN;
|
|
}
|
|
|
|
static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos)
|
|
{
|
|
struct sock *s;
|
|
struct nl_seq_iter *iter;
|
|
int i, j;
|
|
|
|
++*pos;
|
|
|
|
if (v == SEQ_START_TOKEN)
|
|
return netlink_seq_socket_idx(seq, 0);
|
|
|
|
s = sk_next(v);
|
|
if (s)
|
|
return s;
|
|
|
|
iter = seq->private;
|
|
i = iter->link;
|
|
j = iter->hash_idx + 1;
|
|
|
|
do {
|
|
struct nl_pid_hash *hash = &nl_table[i].hash;
|
|
|
|
for (; j <= hash->mask; j++) {
|
|
s = sk_head(&hash->table[j]);
|
|
if (s) {
|
|
iter->link = i;
|
|
iter->hash_idx = j;
|
|
return s;
|
|
}
|
|
}
|
|
|
|
j = 0;
|
|
} while (++i < MAX_LINKS);
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void netlink_seq_stop(struct seq_file *seq, void *v)
|
|
{
|
|
read_unlock(&nl_table_lock);
|
|
}
|
|
|
|
|
|
static int netlink_seq_show(struct seq_file *seq, void *v)
|
|
{
|
|
if (v == SEQ_START_TOKEN)
|
|
seq_puts(seq,
|
|
"sk Eth Pid Groups "
|
|
"Rmem Wmem Dump Locks\n");
|
|
else {
|
|
struct sock *s = v;
|
|
struct netlink_sock *nlk = nlk_sk(s);
|
|
|
|
seq_printf(seq, "%p %-3d %-6d %08x %-8d %-8d %p %d\n",
|
|
s,
|
|
s->sk_protocol,
|
|
nlk->pid,
|
|
nlk->groups,
|
|
atomic_read(&s->sk_rmem_alloc),
|
|
atomic_read(&s->sk_wmem_alloc),
|
|
nlk->cb,
|
|
atomic_read(&s->sk_refcnt)
|
|
);
|
|
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static struct seq_operations netlink_seq_ops = {
|
|
.start = netlink_seq_start,
|
|
.next = netlink_seq_next,
|
|
.stop = netlink_seq_stop,
|
|
.show = netlink_seq_show,
|
|
};
|
|
|
|
|
|
static int netlink_seq_open(struct inode *inode, struct file *file)
|
|
{
|
|
struct seq_file *seq;
|
|
struct nl_seq_iter *iter;
|
|
int err;
|
|
|
|
iter = kmalloc(sizeof(*iter), GFP_KERNEL);
|
|
if (!iter)
|
|
return -ENOMEM;
|
|
|
|
err = seq_open(file, &netlink_seq_ops);
|
|
if (err) {
|
|
kfree(iter);
|
|
return err;
|
|
}
|
|
|
|
memset(iter, 0, sizeof(*iter));
|
|
seq = file->private_data;
|
|
seq->private = iter;
|
|
return 0;
|
|
}
|
|
|
|
static struct file_operations netlink_seq_fops = {
|
|
.owner = THIS_MODULE,
|
|
.open = netlink_seq_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = seq_release_private,
|
|
};
|
|
|
|
#endif
|
|
|
|
int netlink_register_notifier(struct notifier_block *nb)
|
|
{
|
|
return notifier_chain_register(&netlink_chain, nb);
|
|
}
|
|
|
|
int netlink_unregister_notifier(struct notifier_block *nb)
|
|
{
|
|
return notifier_chain_unregister(&netlink_chain, nb);
|
|
}
|
|
|
|
static struct proto_ops netlink_ops = {
|
|
.family = PF_NETLINK,
|
|
.owner = THIS_MODULE,
|
|
.release = netlink_release,
|
|
.bind = netlink_bind,
|
|
.connect = netlink_connect,
|
|
.socketpair = sock_no_socketpair,
|
|
.accept = sock_no_accept,
|
|
.getname = netlink_getname,
|
|
.poll = datagram_poll,
|
|
.ioctl = sock_no_ioctl,
|
|
.listen = sock_no_listen,
|
|
.shutdown = sock_no_shutdown,
|
|
.setsockopt = sock_no_setsockopt,
|
|
.getsockopt = sock_no_getsockopt,
|
|
.sendmsg = netlink_sendmsg,
|
|
.recvmsg = netlink_recvmsg,
|
|
.mmap = sock_no_mmap,
|
|
.sendpage = sock_no_sendpage,
|
|
};
|
|
|
|
static struct net_proto_family netlink_family_ops = {
|
|
.family = PF_NETLINK,
|
|
.create = netlink_create,
|
|
.owner = THIS_MODULE, /* for consistency 8) */
|
|
};
|
|
|
|
extern void netlink_skb_parms_too_large(void);
|
|
|
|
static int __init netlink_proto_init(void)
|
|
{
|
|
struct sk_buff *dummy_skb;
|
|
int i;
|
|
unsigned long max;
|
|
unsigned int order;
|
|
int err = proto_register(&netlink_proto, 0);
|
|
|
|
if (err != 0)
|
|
goto out;
|
|
|
|
if (sizeof(struct netlink_skb_parms) > sizeof(dummy_skb->cb))
|
|
netlink_skb_parms_too_large();
|
|
|
|
nl_table = kmalloc(sizeof(*nl_table) * MAX_LINKS, GFP_KERNEL);
|
|
if (!nl_table) {
|
|
enomem:
|
|
printk(KERN_CRIT "netlink_init: Cannot allocate nl_table\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
memset(nl_table, 0, sizeof(*nl_table) * MAX_LINKS);
|
|
|
|
if (num_physpages >= (128 * 1024))
|
|
max = num_physpages >> (21 - PAGE_SHIFT);
|
|
else
|
|
max = num_physpages >> (23 - PAGE_SHIFT);
|
|
|
|
order = get_bitmask_order(max) - 1 + PAGE_SHIFT;
|
|
max = (1UL << order) / sizeof(struct hlist_head);
|
|
order = get_bitmask_order(max > UINT_MAX ? UINT_MAX : max) - 1;
|
|
|
|
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));
|
|
if (!hash->table) {
|
|
while (i-- > 0)
|
|
nl_pid_hash_free(nl_table[i].hash.table,
|
|
1 * sizeof(*hash->table));
|
|
kfree(nl_table);
|
|
goto enomem;
|
|
}
|
|
memset(hash->table, 0, 1 * sizeof(*hash->table));
|
|
hash->max_shift = order;
|
|
hash->shift = 0;
|
|
hash->mask = 0;
|
|
hash->rehash_time = jiffies;
|
|
}
|
|
|
|
sock_register(&netlink_family_ops);
|
|
#ifdef CONFIG_PROC_FS
|
|
proc_net_fops_create("netlink", 0, &netlink_seq_fops);
|
|
#endif
|
|
/* The netlink device handler may be needed early. */
|
|
rtnetlink_init();
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static void __exit netlink_proto_exit(void)
|
|
{
|
|
sock_unregister(PF_NETLINK);
|
|
proc_net_remove("netlink");
|
|
kfree(nl_table);
|
|
nl_table = NULL;
|
|
proto_unregister(&netlink_proto);
|
|
}
|
|
|
|
core_initcall(netlink_proto_init);
|
|
module_exit(netlink_proto_exit);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
|
|
MODULE_ALIAS_NETPROTO(PF_NETLINK);
|
|
|
|
EXPORT_SYMBOL(netlink_ack);
|
|
EXPORT_SYMBOL(netlink_broadcast);
|
|
EXPORT_SYMBOL(netlink_dump_start);
|
|
EXPORT_SYMBOL(netlink_kernel_create);
|
|
EXPORT_SYMBOL(netlink_register_notifier);
|
|
EXPORT_SYMBOL(netlink_set_err);
|
|
EXPORT_SYMBOL(netlink_set_nonroot);
|
|
EXPORT_SYMBOL(netlink_unicast);
|
|
EXPORT_SYMBOL(netlink_unregister_notifier);
|
|
|