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netlink: Rename pid to portid to avoid confusion
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / netlink / af_netlink.c
1 /*
2 * NETLINK Kernel-user communication protocol.
3 *
4 * Authors: Alan Cox <alan@lxorguk.ukuu.org.uk>
5 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 *
12 * Tue Jun 26 14:36:48 MEST 2001 Herbert "herp" Rosmanith
13 * added netlink_proto_exit
14 * Tue Jan 22 18:32:44 BRST 2002 Arnaldo C. de Melo <acme@conectiva.com.br>
15 * use nlk_sk, as sk->protinfo is on a diet 8)
16 * Fri Jul 22 19:51:12 MEST 2005 Harald Welte <laforge@gnumonks.org>
17 * - inc module use count of module that owns
18 * the kernel socket in case userspace opens
19 * socket of same protocol
20 * - remove all module support, since netlink is
21 * mandatory if CONFIG_NET=y these days
22 */
23
24 #include <linux/module.h>
25
26 #include <linux/capability.h>
27 #include <linux/kernel.h>
28 #include <linux/init.h>
29 #include <linux/signal.h>
30 #include <linux/sched.h>
31 #include <linux/errno.h>
32 #include <linux/string.h>
33 #include <linux/stat.h>
34 #include <linux/socket.h>
35 #include <linux/un.h>
36 #include <linux/fcntl.h>
37 #include <linux/termios.h>
38 #include <linux/sockios.h>
39 #include <linux/net.h>
40 #include <linux/fs.h>
41 #include <linux/slab.h>
42 #include <asm/uaccess.h>
43 #include <linux/skbuff.h>
44 #include <linux/netdevice.h>
45 #include <linux/rtnetlink.h>
46 #include <linux/proc_fs.h>
47 #include <linux/seq_file.h>
48 #include <linux/notifier.h>
49 #include <linux/security.h>
50 #include <linux/jhash.h>
51 #include <linux/jiffies.h>
52 #include <linux/random.h>
53 #include <linux/bitops.h>
54 #include <linux/mm.h>
55 #include <linux/types.h>
56 #include <linux/audit.h>
57 #include <linux/mutex.h>
58
59 #include <net/net_namespace.h>
60 #include <net/sock.h>
61 #include <net/scm.h>
62 #include <net/netlink.h>
63
64 #define NLGRPSZ(x) (ALIGN(x, sizeof(unsigned long) * 8) / 8)
65 #define NLGRPLONGS(x) (NLGRPSZ(x)/sizeof(unsigned long))
66
67 struct netlink_sock {
68 /* struct sock has to be the first member of netlink_sock */
69 struct sock sk;
70 u32 portid;
71 u32 dst_portid;
72 u32 dst_group;
73 u32 flags;
74 u32 subscriptions;
75 u32 ngroups;
76 unsigned long *groups;
77 unsigned long state;
78 wait_queue_head_t wait;
79 struct netlink_callback *cb;
80 struct mutex *cb_mutex;
81 struct mutex cb_def_mutex;
82 void (*netlink_rcv)(struct sk_buff *skb);
83 void (*netlink_bind)(int group);
84 struct module *module;
85 };
86
87 struct listeners {
88 struct rcu_head rcu;
89 unsigned long masks[0];
90 };
91
92 #define NETLINK_KERNEL_SOCKET 0x1
93 #define NETLINK_RECV_PKTINFO 0x2
94 #define NETLINK_BROADCAST_SEND_ERROR 0x4
95 #define NETLINK_RECV_NO_ENOBUFS 0x8
96
97 static inline struct netlink_sock *nlk_sk(struct sock *sk)
98 {
99 return container_of(sk, struct netlink_sock, sk);
100 }
101
102 static inline int netlink_is_kernel(struct sock *sk)
103 {
104 return nlk_sk(sk)->flags & NETLINK_KERNEL_SOCKET;
105 }
106
107 struct nl_portid_hash {
108 struct hlist_head *table;
109 unsigned long rehash_time;
110
111 unsigned int mask;
112 unsigned int shift;
113
114 unsigned int entries;
115 unsigned int max_shift;
116
117 u32 rnd;
118 };
119
120 struct netlink_table {
121 struct nl_portid_hash hash;
122 struct hlist_head mc_list;
123 struct listeners __rcu *listeners;
124 unsigned int flags;
125 unsigned int groups;
126 struct mutex *cb_mutex;
127 struct module *module;
128 void (*bind)(int group);
129 int registered;
130 };
131
132 static struct netlink_table *nl_table;
133
134 static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait);
135
136 static int netlink_dump(struct sock *sk);
137
138 static DEFINE_RWLOCK(nl_table_lock);
139 static atomic_t nl_table_users = ATOMIC_INIT(0);
140
141 static ATOMIC_NOTIFIER_HEAD(netlink_chain);
142
143 static inline u32 netlink_group_mask(u32 group)
144 {
145 return group ? 1 << (group - 1) : 0;
146 }
147
148 static inline struct hlist_head *nl_portid_hashfn(struct nl_portid_hash *hash, u32 portid)
149 {
150 return &hash->table[jhash_1word(portid, hash->rnd) & hash->mask];
151 }
152
153 static void netlink_destroy_callback(struct netlink_callback *cb)
154 {
155 kfree_skb(cb->skb);
156 kfree(cb);
157 }
158
159 static void netlink_consume_callback(struct netlink_callback *cb)
160 {
161 consume_skb(cb->skb);
162 kfree(cb);
163 }
164
165 static void netlink_sock_destruct(struct sock *sk)
166 {
167 struct netlink_sock *nlk = nlk_sk(sk);
168
169 if (nlk->cb) {
170 if (nlk->cb->done)
171 nlk->cb->done(nlk->cb);
172 netlink_destroy_callback(nlk->cb);
173 }
174
175 skb_queue_purge(&sk->sk_receive_queue);
176
177 if (!sock_flag(sk, SOCK_DEAD)) {
178 printk(KERN_ERR "Freeing alive netlink socket %p\n", sk);
179 return;
180 }
181
182 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
183 WARN_ON(atomic_read(&sk->sk_wmem_alloc));
184 WARN_ON(nlk_sk(sk)->groups);
185 }
186
187 /* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on
188 * SMP. Look, when several writers sleep and reader wakes them up, all but one
189 * immediately hit write lock and grab all the cpus. Exclusive sleep solves
190 * this, _but_ remember, it adds useless work on UP machines.
191 */
192
193 void netlink_table_grab(void)
194 __acquires(nl_table_lock)
195 {
196 might_sleep();
197
198 write_lock_irq(&nl_table_lock);
199
200 if (atomic_read(&nl_table_users)) {
201 DECLARE_WAITQUEUE(wait, current);
202
203 add_wait_queue_exclusive(&nl_table_wait, &wait);
204 for (;;) {
205 set_current_state(TASK_UNINTERRUPTIBLE);
206 if (atomic_read(&nl_table_users) == 0)
207 break;
208 write_unlock_irq(&nl_table_lock);
209 schedule();
210 write_lock_irq(&nl_table_lock);
211 }
212
213 __set_current_state(TASK_RUNNING);
214 remove_wait_queue(&nl_table_wait, &wait);
215 }
216 }
217
218 void netlink_table_ungrab(void)
219 __releases(nl_table_lock)
220 {
221 write_unlock_irq(&nl_table_lock);
222 wake_up(&nl_table_wait);
223 }
224
225 static inline void
226 netlink_lock_table(void)
227 {
228 /* read_lock() synchronizes us to netlink_table_grab */
229
230 read_lock(&nl_table_lock);
231 atomic_inc(&nl_table_users);
232 read_unlock(&nl_table_lock);
233 }
234
235 static inline void
236 netlink_unlock_table(void)
237 {
238 if (atomic_dec_and_test(&nl_table_users))
239 wake_up(&nl_table_wait);
240 }
241
242 static struct sock *netlink_lookup(struct net *net, int protocol, u32 portid)
243 {
244 struct nl_portid_hash *hash = &nl_table[protocol].hash;
245 struct hlist_head *head;
246 struct sock *sk;
247 struct hlist_node *node;
248
249 read_lock(&nl_table_lock);
250 head = nl_portid_hashfn(hash, portid);
251 sk_for_each(sk, node, head) {
252 if (net_eq(sock_net(sk), net) && (nlk_sk(sk)->portid == portid)) {
253 sock_hold(sk);
254 goto found;
255 }
256 }
257 sk = NULL;
258 found:
259 read_unlock(&nl_table_lock);
260 return sk;
261 }
262
263 static struct hlist_head *nl_portid_hash_zalloc(size_t size)
264 {
265 if (size <= PAGE_SIZE)
266 return kzalloc(size, GFP_ATOMIC);
267 else
268 return (struct hlist_head *)
269 __get_free_pages(GFP_ATOMIC | __GFP_ZERO,
270 get_order(size));
271 }
272
273 static void nl_portid_hash_free(struct hlist_head *table, size_t size)
274 {
275 if (size <= PAGE_SIZE)
276 kfree(table);
277 else
278 free_pages((unsigned long)table, get_order(size));
279 }
280
281 static int nl_portid_hash_rehash(struct nl_portid_hash *hash, int grow)
282 {
283 unsigned int omask, mask, shift;
284 size_t osize, size;
285 struct hlist_head *otable, *table;
286 int i;
287
288 omask = mask = hash->mask;
289 osize = size = (mask + 1) * sizeof(*table);
290 shift = hash->shift;
291
292 if (grow) {
293 if (++shift > hash->max_shift)
294 return 0;
295 mask = mask * 2 + 1;
296 size *= 2;
297 }
298
299 table = nl_portid_hash_zalloc(size);
300 if (!table)
301 return 0;
302
303 otable = hash->table;
304 hash->table = table;
305 hash->mask = mask;
306 hash->shift = shift;
307 get_random_bytes(&hash->rnd, sizeof(hash->rnd));
308
309 for (i = 0; i <= omask; i++) {
310 struct sock *sk;
311 struct hlist_node *node, *tmp;
312
313 sk_for_each_safe(sk, node, tmp, &otable[i])
314 __sk_add_node(sk, nl_portid_hashfn(hash, nlk_sk(sk)->portid));
315 }
316
317 nl_portid_hash_free(otable, osize);
318 hash->rehash_time = jiffies + 10 * 60 * HZ;
319 return 1;
320 }
321
322 static inline int nl_portid_hash_dilute(struct nl_portid_hash *hash, int len)
323 {
324 int avg = hash->entries >> hash->shift;
325
326 if (unlikely(avg > 1) && nl_portid_hash_rehash(hash, 1))
327 return 1;
328
329 if (unlikely(len > avg) && time_after(jiffies, hash->rehash_time)) {
330 nl_portid_hash_rehash(hash, 0);
331 return 1;
332 }
333
334 return 0;
335 }
336
337 static const struct proto_ops netlink_ops;
338
339 static void
340 netlink_update_listeners(struct sock *sk)
341 {
342 struct netlink_table *tbl = &nl_table[sk->sk_protocol];
343 struct hlist_node *node;
344 unsigned long mask;
345 unsigned int i;
346
347 for (i = 0; i < NLGRPLONGS(tbl->groups); i++) {
348 mask = 0;
349 sk_for_each_bound(sk, node, &tbl->mc_list) {
350 if (i < NLGRPLONGS(nlk_sk(sk)->ngroups))
351 mask |= nlk_sk(sk)->groups[i];
352 }
353 tbl->listeners->masks[i] = mask;
354 }
355 /* this function is only called with the netlink table "grabbed", which
356 * makes sure updates are visible before bind or setsockopt return. */
357 }
358
359 static int netlink_insert(struct sock *sk, struct net *net, u32 portid)
360 {
361 struct nl_portid_hash *hash = &nl_table[sk->sk_protocol].hash;
362 struct hlist_head *head;
363 int err = -EADDRINUSE;
364 struct sock *osk;
365 struct hlist_node *node;
366 int len;
367
368 netlink_table_grab();
369 head = nl_portid_hashfn(hash, portid);
370 len = 0;
371 sk_for_each(osk, node, head) {
372 if (net_eq(sock_net(osk), net) && (nlk_sk(osk)->portid == portid))
373 break;
374 len++;
375 }
376 if (node)
377 goto err;
378
379 err = -EBUSY;
380 if (nlk_sk(sk)->portid)
381 goto err;
382
383 err = -ENOMEM;
384 if (BITS_PER_LONG > 32 && unlikely(hash->entries >= UINT_MAX))
385 goto err;
386
387 if (len && nl_portid_hash_dilute(hash, len))
388 head = nl_portid_hashfn(hash, portid);
389 hash->entries++;
390 nlk_sk(sk)->portid = portid;
391 sk_add_node(sk, head);
392 err = 0;
393
394 err:
395 netlink_table_ungrab();
396 return err;
397 }
398
399 static void netlink_remove(struct sock *sk)
400 {
401 netlink_table_grab();
402 if (sk_del_node_init(sk))
403 nl_table[sk->sk_protocol].hash.entries--;
404 if (nlk_sk(sk)->subscriptions)
405 __sk_del_bind_node(sk);
406 netlink_table_ungrab();
407 }
408
409 static struct proto netlink_proto = {
410 .name = "NETLINK",
411 .owner = THIS_MODULE,
412 .obj_size = sizeof(struct netlink_sock),
413 };
414
415 static int __netlink_create(struct net *net, struct socket *sock,
416 struct mutex *cb_mutex, int protocol)
417 {
418 struct sock *sk;
419 struct netlink_sock *nlk;
420
421 sock->ops = &netlink_ops;
422
423 sk = sk_alloc(net, PF_NETLINK, GFP_KERNEL, &netlink_proto);
424 if (!sk)
425 return -ENOMEM;
426
427 sock_init_data(sock, sk);
428
429 nlk = nlk_sk(sk);
430 if (cb_mutex) {
431 nlk->cb_mutex = cb_mutex;
432 } else {
433 nlk->cb_mutex = &nlk->cb_def_mutex;
434 mutex_init(nlk->cb_mutex);
435 }
436 init_waitqueue_head(&nlk->wait);
437
438 sk->sk_destruct = netlink_sock_destruct;
439 sk->sk_protocol = protocol;
440 return 0;
441 }
442
443 static int netlink_create(struct net *net, struct socket *sock, int protocol,
444 int kern)
445 {
446 struct module *module = NULL;
447 struct mutex *cb_mutex;
448 struct netlink_sock *nlk;
449 void (*bind)(int group);
450 int err = 0;
451
452 sock->state = SS_UNCONNECTED;
453
454 if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM)
455 return -ESOCKTNOSUPPORT;
456
457 if (protocol < 0 || protocol >= MAX_LINKS)
458 return -EPROTONOSUPPORT;
459
460 netlink_lock_table();
461 #ifdef CONFIG_MODULES
462 if (!nl_table[protocol].registered) {
463 netlink_unlock_table();
464 request_module("net-pf-%d-proto-%d", PF_NETLINK, protocol);
465 netlink_lock_table();
466 }
467 #endif
468 if (nl_table[protocol].registered &&
469 try_module_get(nl_table[protocol].module))
470 module = nl_table[protocol].module;
471 else
472 err = -EPROTONOSUPPORT;
473 cb_mutex = nl_table[protocol].cb_mutex;
474 bind = nl_table[protocol].bind;
475 netlink_unlock_table();
476
477 if (err < 0)
478 goto out;
479
480 err = __netlink_create(net, sock, cb_mutex, protocol);
481 if (err < 0)
482 goto out_module;
483
484 local_bh_disable();
485 sock_prot_inuse_add(net, &netlink_proto, 1);
486 local_bh_enable();
487
488 nlk = nlk_sk(sock->sk);
489 nlk->module = module;
490 nlk->netlink_bind = bind;
491 out:
492 return err;
493
494 out_module:
495 module_put(module);
496 goto out;
497 }
498
499 static int netlink_release(struct socket *sock)
500 {
501 struct sock *sk = sock->sk;
502 struct netlink_sock *nlk;
503
504 if (!sk)
505 return 0;
506
507 netlink_remove(sk);
508 sock_orphan(sk);
509 nlk = nlk_sk(sk);
510
511 /*
512 * OK. Socket is unlinked, any packets that arrive now
513 * will be purged.
514 */
515
516 sock->sk = NULL;
517 wake_up_interruptible_all(&nlk->wait);
518
519 skb_queue_purge(&sk->sk_write_queue);
520
521 if (nlk->portid) {
522 struct netlink_notify n = {
523 .net = sock_net(sk),
524 .protocol = sk->sk_protocol,
525 .portid = nlk->portid,
526 };
527 atomic_notifier_call_chain(&netlink_chain,
528 NETLINK_URELEASE, &n);
529 }
530
531 module_put(nlk->module);
532
533 netlink_table_grab();
534 if (netlink_is_kernel(sk)) {
535 BUG_ON(nl_table[sk->sk_protocol].registered == 0);
536 if (--nl_table[sk->sk_protocol].registered == 0) {
537 kfree(nl_table[sk->sk_protocol].listeners);
538 nl_table[sk->sk_protocol].module = NULL;
539 nl_table[sk->sk_protocol].bind = NULL;
540 nl_table[sk->sk_protocol].flags = 0;
541 nl_table[sk->sk_protocol].registered = 0;
542 }
543 } else if (nlk->subscriptions) {
544 netlink_update_listeners(sk);
545 }
546 netlink_table_ungrab();
547
548 kfree(nlk->groups);
549 nlk->groups = NULL;
550
551 local_bh_disable();
552 sock_prot_inuse_add(sock_net(sk), &netlink_proto, -1);
553 local_bh_enable();
554 sock_put(sk);
555 return 0;
556 }
557
558 static int netlink_autobind(struct socket *sock)
559 {
560 struct sock *sk = sock->sk;
561 struct net *net = sock_net(sk);
562 struct nl_portid_hash *hash = &nl_table[sk->sk_protocol].hash;
563 struct hlist_head *head;
564 struct sock *osk;
565 struct hlist_node *node;
566 s32 portid = task_tgid_vnr(current);
567 int err;
568 static s32 rover = -4097;
569
570 retry:
571 cond_resched();
572 netlink_table_grab();
573 head = nl_portid_hashfn(hash, portid);
574 sk_for_each(osk, node, head) {
575 if (!net_eq(sock_net(osk), net))
576 continue;
577 if (nlk_sk(osk)->portid == portid) {
578 /* Bind collision, search negative portid values. */
579 portid = rover--;
580 if (rover > -4097)
581 rover = -4097;
582 netlink_table_ungrab();
583 goto retry;
584 }
585 }
586 netlink_table_ungrab();
587
588 err = netlink_insert(sk, net, portid);
589 if (err == -EADDRINUSE)
590 goto retry;
591
592 /* If 2 threads race to autobind, that is fine. */
593 if (err == -EBUSY)
594 err = 0;
595
596 return err;
597 }
598
599 static inline int netlink_capable(const struct socket *sock, unsigned int flag)
600 {
601 return (nl_table[sock->sk->sk_protocol].flags & flag) ||
602 capable(CAP_NET_ADMIN);
603 }
604
605 static void
606 netlink_update_subscriptions(struct sock *sk, unsigned int subscriptions)
607 {
608 struct netlink_sock *nlk = nlk_sk(sk);
609
610 if (nlk->subscriptions && !subscriptions)
611 __sk_del_bind_node(sk);
612 else if (!nlk->subscriptions && subscriptions)
613 sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list);
614 nlk->subscriptions = subscriptions;
615 }
616
617 static int netlink_realloc_groups(struct sock *sk)
618 {
619 struct netlink_sock *nlk = nlk_sk(sk);
620 unsigned int groups;
621 unsigned long *new_groups;
622 int err = 0;
623
624 netlink_table_grab();
625
626 groups = nl_table[sk->sk_protocol].groups;
627 if (!nl_table[sk->sk_protocol].registered) {
628 err = -ENOENT;
629 goto out_unlock;
630 }
631
632 if (nlk->ngroups >= groups)
633 goto out_unlock;
634
635 new_groups = krealloc(nlk->groups, NLGRPSZ(groups), GFP_ATOMIC);
636 if (new_groups == NULL) {
637 err = -ENOMEM;
638 goto out_unlock;
639 }
640 memset((char *)new_groups + NLGRPSZ(nlk->ngroups), 0,
641 NLGRPSZ(groups) - NLGRPSZ(nlk->ngroups));
642
643 nlk->groups = new_groups;
644 nlk->ngroups = groups;
645 out_unlock:
646 netlink_table_ungrab();
647 return err;
648 }
649
650 static int netlink_bind(struct socket *sock, struct sockaddr *addr,
651 int addr_len)
652 {
653 struct sock *sk = sock->sk;
654 struct net *net = sock_net(sk);
655 struct netlink_sock *nlk = nlk_sk(sk);
656 struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
657 int err;
658
659 if (nladdr->nl_family != AF_NETLINK)
660 return -EINVAL;
661
662 /* Only superuser is allowed to listen multicasts */
663 if (nladdr->nl_groups) {
664 if (!netlink_capable(sock, NL_CFG_F_NONROOT_RECV))
665 return -EPERM;
666 err = netlink_realloc_groups(sk);
667 if (err)
668 return err;
669 }
670
671 if (nlk->portid) {
672 if (nladdr->nl_pid != nlk->portid)
673 return -EINVAL;
674 } else {
675 err = nladdr->nl_pid ?
676 netlink_insert(sk, net, nladdr->nl_pid) :
677 netlink_autobind(sock);
678 if (err)
679 return err;
680 }
681
682 if (!nladdr->nl_groups && (nlk->groups == NULL || !(u32)nlk->groups[0]))
683 return 0;
684
685 netlink_table_grab();
686 netlink_update_subscriptions(sk, nlk->subscriptions +
687 hweight32(nladdr->nl_groups) -
688 hweight32(nlk->groups[0]));
689 nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | nladdr->nl_groups;
690 netlink_update_listeners(sk);
691 netlink_table_ungrab();
692
693 if (nlk->netlink_bind && nlk->groups[0]) {
694 int i;
695
696 for (i=0; i<nlk->ngroups; i++) {
697 if (test_bit(i, nlk->groups))
698 nlk->netlink_bind(i);
699 }
700 }
701
702 return 0;
703 }
704
705 static int netlink_connect(struct socket *sock, struct sockaddr *addr,
706 int alen, int flags)
707 {
708 int err = 0;
709 struct sock *sk = sock->sk;
710 struct netlink_sock *nlk = nlk_sk(sk);
711 struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr;
712
713 if (alen < sizeof(addr->sa_family))
714 return -EINVAL;
715
716 if (addr->sa_family == AF_UNSPEC) {
717 sk->sk_state = NETLINK_UNCONNECTED;
718 nlk->dst_portid = 0;
719 nlk->dst_group = 0;
720 return 0;
721 }
722 if (addr->sa_family != AF_NETLINK)
723 return -EINVAL;
724
725 /* Only superuser is allowed to send multicasts */
726 if (nladdr->nl_groups && !netlink_capable(sock, NL_CFG_F_NONROOT_SEND))
727 return -EPERM;
728
729 if (!nlk->portid)
730 err = netlink_autobind(sock);
731
732 if (err == 0) {
733 sk->sk_state = NETLINK_CONNECTED;
734 nlk->dst_portid = nladdr->nl_pid;
735 nlk->dst_group = ffs(nladdr->nl_groups);
736 }
737
738 return err;
739 }
740
741 static int netlink_getname(struct socket *sock, struct sockaddr *addr,
742 int *addr_len, int peer)
743 {
744 struct sock *sk = sock->sk;
745 struct netlink_sock *nlk = nlk_sk(sk);
746 DECLARE_SOCKADDR(struct sockaddr_nl *, nladdr, addr);
747
748 nladdr->nl_family = AF_NETLINK;
749 nladdr->nl_pad = 0;
750 *addr_len = sizeof(*nladdr);
751
752 if (peer) {
753 nladdr->nl_pid = nlk->dst_portid;
754 nladdr->nl_groups = netlink_group_mask(nlk->dst_group);
755 } else {
756 nladdr->nl_pid = nlk->portid;
757 nladdr->nl_groups = nlk->groups ? nlk->groups[0] : 0;
758 }
759 return 0;
760 }
761
762 static void netlink_overrun(struct sock *sk)
763 {
764 struct netlink_sock *nlk = nlk_sk(sk);
765
766 if (!(nlk->flags & NETLINK_RECV_NO_ENOBUFS)) {
767 if (!test_and_set_bit(0, &nlk_sk(sk)->state)) {
768 sk->sk_err = ENOBUFS;
769 sk->sk_error_report(sk);
770 }
771 }
772 atomic_inc(&sk->sk_drops);
773 }
774
775 static struct sock *netlink_getsockbyportid(struct sock *ssk, u32 portid)
776 {
777 struct sock *sock;
778 struct netlink_sock *nlk;
779
780 sock = netlink_lookup(sock_net(ssk), ssk->sk_protocol, portid);
781 if (!sock)
782 return ERR_PTR(-ECONNREFUSED);
783
784 /* Don't bother queuing skb if kernel socket has no input function */
785 nlk = nlk_sk(sock);
786 if (sock->sk_state == NETLINK_CONNECTED &&
787 nlk->dst_portid != nlk_sk(ssk)->portid) {
788 sock_put(sock);
789 return ERR_PTR(-ECONNREFUSED);
790 }
791 return sock;
792 }
793
794 struct sock *netlink_getsockbyfilp(struct file *filp)
795 {
796 struct inode *inode = filp->f_path.dentry->d_inode;
797 struct sock *sock;
798
799 if (!S_ISSOCK(inode->i_mode))
800 return ERR_PTR(-ENOTSOCK);
801
802 sock = SOCKET_I(inode)->sk;
803 if (sock->sk_family != AF_NETLINK)
804 return ERR_PTR(-EINVAL);
805
806 sock_hold(sock);
807 return sock;
808 }
809
810 /*
811 * Attach a skb to a netlink socket.
812 * The caller must hold a reference to the destination socket. On error, the
813 * reference is dropped. The skb is not send to the destination, just all
814 * all error checks are performed and memory in the queue is reserved.
815 * Return values:
816 * < 0: error. skb freed, reference to sock dropped.
817 * 0: continue
818 * 1: repeat lookup - reference dropped while waiting for socket memory.
819 */
820 int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
821 long *timeo, struct sock *ssk)
822 {
823 struct netlink_sock *nlk;
824
825 nlk = nlk_sk(sk);
826
827 if (atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
828 test_bit(0, &nlk->state)) {
829 DECLARE_WAITQUEUE(wait, current);
830 if (!*timeo) {
831 if (!ssk || netlink_is_kernel(ssk))
832 netlink_overrun(sk);
833 sock_put(sk);
834 kfree_skb(skb);
835 return -EAGAIN;
836 }
837
838 __set_current_state(TASK_INTERRUPTIBLE);
839 add_wait_queue(&nlk->wait, &wait);
840
841 if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf ||
842 test_bit(0, &nlk->state)) &&
843 !sock_flag(sk, SOCK_DEAD))
844 *timeo = schedule_timeout(*timeo);
845
846 __set_current_state(TASK_RUNNING);
847 remove_wait_queue(&nlk->wait, &wait);
848 sock_put(sk);
849
850 if (signal_pending(current)) {
851 kfree_skb(skb);
852 return sock_intr_errno(*timeo);
853 }
854 return 1;
855 }
856 skb_set_owner_r(skb, sk);
857 return 0;
858 }
859
860 static int __netlink_sendskb(struct sock *sk, struct sk_buff *skb)
861 {
862 int len = skb->len;
863
864 skb_queue_tail(&sk->sk_receive_queue, skb);
865 sk->sk_data_ready(sk, len);
866 return len;
867 }
868
869 int netlink_sendskb(struct sock *sk, struct sk_buff *skb)
870 {
871 int len = __netlink_sendskb(sk, skb);
872
873 sock_put(sk);
874 return len;
875 }
876
877 void netlink_detachskb(struct sock *sk, struct sk_buff *skb)
878 {
879 kfree_skb(skb);
880 sock_put(sk);
881 }
882
883 static struct sk_buff *netlink_trim(struct sk_buff *skb, gfp_t allocation)
884 {
885 int delta;
886
887 skb_orphan(skb);
888
889 delta = skb->end - skb->tail;
890 if (delta * 2 < skb->truesize)
891 return skb;
892
893 if (skb_shared(skb)) {
894 struct sk_buff *nskb = skb_clone(skb, allocation);
895 if (!nskb)
896 return skb;
897 consume_skb(skb);
898 skb = nskb;
899 }
900
901 if (!pskb_expand_head(skb, 0, -delta, allocation))
902 skb->truesize -= delta;
903
904 return skb;
905 }
906
907 static void netlink_rcv_wake(struct sock *sk)
908 {
909 struct netlink_sock *nlk = nlk_sk(sk);
910
911 if (skb_queue_empty(&sk->sk_receive_queue))
912 clear_bit(0, &nlk->state);
913 if (!test_bit(0, &nlk->state))
914 wake_up_interruptible(&nlk->wait);
915 }
916
917 static int netlink_unicast_kernel(struct sock *sk, struct sk_buff *skb,
918 struct sock *ssk)
919 {
920 int ret;
921 struct netlink_sock *nlk = nlk_sk(sk);
922
923 ret = -ECONNREFUSED;
924 if (nlk->netlink_rcv != NULL) {
925 ret = skb->len;
926 skb_set_owner_r(skb, sk);
927 NETLINK_CB(skb).ssk = ssk;
928 nlk->netlink_rcv(skb);
929 consume_skb(skb);
930 } else {
931 kfree_skb(skb);
932 }
933 sock_put(sk);
934 return ret;
935 }
936
937 int netlink_unicast(struct sock *ssk, struct sk_buff *skb,
938 u32 portid, int nonblock)
939 {
940 struct sock *sk;
941 int err;
942 long timeo;
943
944 skb = netlink_trim(skb, gfp_any());
945
946 timeo = sock_sndtimeo(ssk, nonblock);
947 retry:
948 sk = netlink_getsockbyportid(ssk, portid);
949 if (IS_ERR(sk)) {
950 kfree_skb(skb);
951 return PTR_ERR(sk);
952 }
953 if (netlink_is_kernel(sk))
954 return netlink_unicast_kernel(sk, skb, ssk);
955
956 if (sk_filter(sk, skb)) {
957 err = skb->len;
958 kfree_skb(skb);
959 sock_put(sk);
960 return err;
961 }
962
963 err = netlink_attachskb(sk, skb, &timeo, ssk);
964 if (err == 1)
965 goto retry;
966 if (err)
967 return err;
968
969 return netlink_sendskb(sk, skb);
970 }
971 EXPORT_SYMBOL(netlink_unicast);
972
973 int netlink_has_listeners(struct sock *sk, unsigned int group)
974 {
975 int res = 0;
976 struct listeners *listeners;
977
978 BUG_ON(!netlink_is_kernel(sk));
979
980 rcu_read_lock();
981 listeners = rcu_dereference(nl_table[sk->sk_protocol].listeners);
982
983 if (group - 1 < nl_table[sk->sk_protocol].groups)
984 res = test_bit(group - 1, listeners->masks);
985
986 rcu_read_unlock();
987
988 return res;
989 }
990 EXPORT_SYMBOL_GPL(netlink_has_listeners);
991
992 static int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb)
993 {
994 struct netlink_sock *nlk = nlk_sk(sk);
995
996 if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf &&
997 !test_bit(0, &nlk->state)) {
998 skb_set_owner_r(skb, sk);
999 __netlink_sendskb(sk, skb);
1000 return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1);
1001 }
1002 return -1;
1003 }
1004
1005 struct netlink_broadcast_data {
1006 struct sock *exclude_sk;
1007 struct net *net;
1008 u32 portid;
1009 u32 group;
1010 int failure;
1011 int delivery_failure;
1012 int congested;
1013 int delivered;
1014 gfp_t allocation;
1015 struct sk_buff *skb, *skb2;
1016 int (*tx_filter)(struct sock *dsk, struct sk_buff *skb, void *data);
1017 void *tx_data;
1018 };
1019
1020 static int do_one_broadcast(struct sock *sk,
1021 struct netlink_broadcast_data *p)
1022 {
1023 struct netlink_sock *nlk = nlk_sk(sk);
1024 int val;
1025
1026 if (p->exclude_sk == sk)
1027 goto out;
1028
1029 if (nlk->portid == p->portid || p->group - 1 >= nlk->ngroups ||
1030 !test_bit(p->group - 1, nlk->groups))
1031 goto out;
1032
1033 if (!net_eq(sock_net(sk), p->net))
1034 goto out;
1035
1036 if (p->failure) {
1037 netlink_overrun(sk);
1038 goto out;
1039 }
1040
1041 sock_hold(sk);
1042 if (p->skb2 == NULL) {
1043 if (skb_shared(p->skb)) {
1044 p->skb2 = skb_clone(p->skb, p->allocation);
1045 } else {
1046 p->skb2 = skb_get(p->skb);
1047 /*
1048 * skb ownership may have been set when
1049 * delivered to a previous socket.
1050 */
1051 skb_orphan(p->skb2);
1052 }
1053 }
1054 if (p->skb2 == NULL) {
1055 netlink_overrun(sk);
1056 /* Clone failed. Notify ALL listeners. */
1057 p->failure = 1;
1058 if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR)
1059 p->delivery_failure = 1;
1060 } else if (p->tx_filter && p->tx_filter(sk, p->skb2, p->tx_data)) {
1061 kfree_skb(p->skb2);
1062 p->skb2 = NULL;
1063 } else if (sk_filter(sk, p->skb2)) {
1064 kfree_skb(p->skb2);
1065 p->skb2 = NULL;
1066 } else if ((val = netlink_broadcast_deliver(sk, p->skb2)) < 0) {
1067 netlink_overrun(sk);
1068 if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR)
1069 p->delivery_failure = 1;
1070 } else {
1071 p->congested |= val;
1072 p->delivered = 1;
1073 p->skb2 = NULL;
1074 }
1075 sock_put(sk);
1076
1077 out:
1078 return 0;
1079 }
1080
1081 int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, u32 portid,
1082 u32 group, gfp_t allocation,
1083 int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
1084 void *filter_data)
1085 {
1086 struct net *net = sock_net(ssk);
1087 struct netlink_broadcast_data info;
1088 struct hlist_node *node;
1089 struct sock *sk;
1090
1091 skb = netlink_trim(skb, allocation);
1092
1093 info.exclude_sk = ssk;
1094 info.net = net;
1095 info.portid = portid;
1096 info.group = group;
1097 info.failure = 0;
1098 info.delivery_failure = 0;
1099 info.congested = 0;
1100 info.delivered = 0;
1101 info.allocation = allocation;
1102 info.skb = skb;
1103 info.skb2 = NULL;
1104 info.tx_filter = filter;
1105 info.tx_data = filter_data;
1106
1107 /* While we sleep in clone, do not allow to change socket list */
1108
1109 netlink_lock_table();
1110
1111 sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
1112 do_one_broadcast(sk, &info);
1113
1114 consume_skb(skb);
1115
1116 netlink_unlock_table();
1117
1118 if (info.delivery_failure) {
1119 kfree_skb(info.skb2);
1120 return -ENOBUFS;
1121 }
1122 consume_skb(info.skb2);
1123
1124 if (info.delivered) {
1125 if (info.congested && (allocation & __GFP_WAIT))
1126 yield();
1127 return 0;
1128 }
1129 return -ESRCH;
1130 }
1131 EXPORT_SYMBOL(netlink_broadcast_filtered);
1132
1133 int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 portid,
1134 u32 group, gfp_t allocation)
1135 {
1136 return netlink_broadcast_filtered(ssk, skb, portid, group, allocation,
1137 NULL, NULL);
1138 }
1139 EXPORT_SYMBOL(netlink_broadcast);
1140
1141 struct netlink_set_err_data {
1142 struct sock *exclude_sk;
1143 u32 portid;
1144 u32 group;
1145 int code;
1146 };
1147
1148 static int do_one_set_err(struct sock *sk, struct netlink_set_err_data *p)
1149 {
1150 struct netlink_sock *nlk = nlk_sk(sk);
1151 int ret = 0;
1152
1153 if (sk == p->exclude_sk)
1154 goto out;
1155
1156 if (!net_eq(sock_net(sk), sock_net(p->exclude_sk)))
1157 goto out;
1158
1159 if (nlk->portid == p->portid || p->group - 1 >= nlk->ngroups ||
1160 !test_bit(p->group - 1, nlk->groups))
1161 goto out;
1162
1163 if (p->code == ENOBUFS && nlk->flags & NETLINK_RECV_NO_ENOBUFS) {
1164 ret = 1;
1165 goto out;
1166 }
1167
1168 sk->sk_err = p->code;
1169 sk->sk_error_report(sk);
1170 out:
1171 return ret;
1172 }
1173
1174 /**
1175 * netlink_set_err - report error to broadcast listeners
1176 * @ssk: the kernel netlink socket, as returned by netlink_kernel_create()
1177 * @portid: the PORTID of a process that we want to skip (if any)
1178 * @groups: the broadcast group that will notice the error
1179 * @code: error code, must be negative (as usual in kernelspace)
1180 *
1181 * This function returns the number of broadcast listeners that have set the
1182 * NETLINK_RECV_NO_ENOBUFS socket option.
1183 */
1184 int netlink_set_err(struct sock *ssk, u32 portid, u32 group, int code)
1185 {
1186 struct netlink_set_err_data info;
1187 struct hlist_node *node;
1188 struct sock *sk;
1189 int ret = 0;
1190
1191 info.exclude_sk = ssk;
1192 info.portid = portid;
1193 info.group = group;
1194 /* sk->sk_err wants a positive error value */
1195 info.code = -code;
1196
1197 read_lock(&nl_table_lock);
1198
1199 sk_for_each_bound(sk, node, &nl_table[ssk->sk_protocol].mc_list)
1200 ret += do_one_set_err(sk, &info);
1201
1202 read_unlock(&nl_table_lock);
1203 return ret;
1204 }
1205 EXPORT_SYMBOL(netlink_set_err);
1206
1207 /* must be called with netlink table grabbed */
1208 static void netlink_update_socket_mc(struct netlink_sock *nlk,
1209 unsigned int group,
1210 int is_new)
1211 {
1212 int old, new = !!is_new, subscriptions;
1213
1214 old = test_bit(group - 1, nlk->groups);
1215 subscriptions = nlk->subscriptions - old + new;
1216 if (new)
1217 __set_bit(group - 1, nlk->groups);
1218 else
1219 __clear_bit(group - 1, nlk->groups);
1220 netlink_update_subscriptions(&nlk->sk, subscriptions);
1221 netlink_update_listeners(&nlk->sk);
1222 }
1223
1224 static int netlink_setsockopt(struct socket *sock, int level, int optname,
1225 char __user *optval, unsigned int optlen)
1226 {
1227 struct sock *sk = sock->sk;
1228 struct netlink_sock *nlk = nlk_sk(sk);
1229 unsigned int val = 0;
1230 int err;
1231
1232 if (level != SOL_NETLINK)
1233 return -ENOPROTOOPT;
1234
1235 if (optlen >= sizeof(int) &&
1236 get_user(val, (unsigned int __user *)optval))
1237 return -EFAULT;
1238
1239 switch (optname) {
1240 case NETLINK_PKTINFO:
1241 if (val)
1242 nlk->flags |= NETLINK_RECV_PKTINFO;
1243 else
1244 nlk->flags &= ~NETLINK_RECV_PKTINFO;
1245 err = 0;
1246 break;
1247 case NETLINK_ADD_MEMBERSHIP:
1248 case NETLINK_DROP_MEMBERSHIP: {
1249 if (!netlink_capable(sock, NL_CFG_F_NONROOT_RECV))
1250 return -EPERM;
1251 err = netlink_realloc_groups(sk);
1252 if (err)
1253 return err;
1254 if (!val || val - 1 >= nlk->ngroups)
1255 return -EINVAL;
1256 netlink_table_grab();
1257 netlink_update_socket_mc(nlk, val,
1258 optname == NETLINK_ADD_MEMBERSHIP);
1259 netlink_table_ungrab();
1260
1261 if (nlk->netlink_bind)
1262 nlk->netlink_bind(val);
1263
1264 err = 0;
1265 break;
1266 }
1267 case NETLINK_BROADCAST_ERROR:
1268 if (val)
1269 nlk->flags |= NETLINK_BROADCAST_SEND_ERROR;
1270 else
1271 nlk->flags &= ~NETLINK_BROADCAST_SEND_ERROR;
1272 err = 0;
1273 break;
1274 case NETLINK_NO_ENOBUFS:
1275 if (val) {
1276 nlk->flags |= NETLINK_RECV_NO_ENOBUFS;
1277 clear_bit(0, &nlk->state);
1278 wake_up_interruptible(&nlk->wait);
1279 } else {
1280 nlk->flags &= ~NETLINK_RECV_NO_ENOBUFS;
1281 }
1282 err = 0;
1283 break;
1284 default:
1285 err = -ENOPROTOOPT;
1286 }
1287 return err;
1288 }
1289
1290 static int netlink_getsockopt(struct socket *sock, int level, int optname,
1291 char __user *optval, int __user *optlen)
1292 {
1293 struct sock *sk = sock->sk;
1294 struct netlink_sock *nlk = nlk_sk(sk);
1295 int len, val, err;
1296
1297 if (level != SOL_NETLINK)
1298 return -ENOPROTOOPT;
1299
1300 if (get_user(len, optlen))
1301 return -EFAULT;
1302 if (len < 0)
1303 return -EINVAL;
1304
1305 switch (optname) {
1306 case NETLINK_PKTINFO:
1307 if (len < sizeof(int))
1308 return -EINVAL;
1309 len = sizeof(int);
1310 val = nlk->flags & NETLINK_RECV_PKTINFO ? 1 : 0;
1311 if (put_user(len, optlen) ||
1312 put_user(val, optval))
1313 return -EFAULT;
1314 err = 0;
1315 break;
1316 case NETLINK_BROADCAST_ERROR:
1317 if (len < sizeof(int))
1318 return -EINVAL;
1319 len = sizeof(int);
1320 val = nlk->flags & NETLINK_BROADCAST_SEND_ERROR ? 1 : 0;
1321 if (put_user(len, optlen) ||
1322 put_user(val, optval))
1323 return -EFAULT;
1324 err = 0;
1325 break;
1326 case NETLINK_NO_ENOBUFS:
1327 if (len < sizeof(int))
1328 return -EINVAL;
1329 len = sizeof(int);
1330 val = nlk->flags & NETLINK_RECV_NO_ENOBUFS ? 1 : 0;
1331 if (put_user(len, optlen) ||
1332 put_user(val, optval))
1333 return -EFAULT;
1334 err = 0;
1335 break;
1336 default:
1337 err = -ENOPROTOOPT;
1338 }
1339 return err;
1340 }
1341
1342 static void netlink_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
1343 {
1344 struct nl_pktinfo info;
1345
1346 info.group = NETLINK_CB(skb).dst_group;
1347 put_cmsg(msg, SOL_NETLINK, NETLINK_PKTINFO, sizeof(info), &info);
1348 }
1349
1350 static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
1351 struct msghdr *msg, size_t len)
1352 {
1353 struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
1354 struct sock *sk = sock->sk;
1355 struct netlink_sock *nlk = nlk_sk(sk);
1356 struct sockaddr_nl *addr = msg->msg_name;
1357 u32 dst_portid;
1358 u32 dst_group;
1359 struct sk_buff *skb;
1360 int err;
1361 struct scm_cookie scm;
1362
1363 if (msg->msg_flags&MSG_OOB)
1364 return -EOPNOTSUPP;
1365
1366 if (NULL == siocb->scm)
1367 siocb->scm = &scm;
1368
1369 err = scm_send(sock, msg, siocb->scm, true);
1370 if (err < 0)
1371 return err;
1372
1373 if (msg->msg_namelen) {
1374 err = -EINVAL;
1375 if (addr->nl_family != AF_NETLINK)
1376 goto out;
1377 dst_portid = addr->nl_pid;
1378 dst_group = ffs(addr->nl_groups);
1379 err = -EPERM;
1380 if ((dst_group || dst_portid) &&
1381 !netlink_capable(sock, NL_CFG_F_NONROOT_SEND))
1382 goto out;
1383 } else {
1384 dst_portid = nlk->dst_portid;
1385 dst_group = nlk->dst_group;
1386 }
1387
1388 if (!nlk->portid) {
1389 err = netlink_autobind(sock);
1390 if (err)
1391 goto out;
1392 }
1393
1394 err = -EMSGSIZE;
1395 if (len > sk->sk_sndbuf - 32)
1396 goto out;
1397 err = -ENOBUFS;
1398 skb = alloc_skb(len, GFP_KERNEL);
1399 if (skb == NULL)
1400 goto out;
1401
1402 NETLINK_CB(skb).portid = nlk->portid;
1403 NETLINK_CB(skb).dst_group = dst_group;
1404 NETLINK_CB(skb).creds = siocb->scm->creds;
1405
1406 err = -EFAULT;
1407 if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
1408 kfree_skb(skb);
1409 goto out;
1410 }
1411
1412 err = security_netlink_send(sk, skb);
1413 if (err) {
1414 kfree_skb(skb);
1415 goto out;
1416 }
1417
1418 if (dst_group) {
1419 atomic_inc(&skb->users);
1420 netlink_broadcast(sk, skb, dst_portid, dst_group, GFP_KERNEL);
1421 }
1422 err = netlink_unicast(sk, skb, dst_portid, msg->msg_flags&MSG_DONTWAIT);
1423
1424 out:
1425 scm_destroy(siocb->scm);
1426 return err;
1427 }
1428
1429 static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
1430 struct msghdr *msg, size_t len,
1431 int flags)
1432 {
1433 struct sock_iocb *siocb = kiocb_to_siocb(kiocb);
1434 struct scm_cookie scm;
1435 struct sock *sk = sock->sk;
1436 struct netlink_sock *nlk = nlk_sk(sk);
1437 int noblock = flags&MSG_DONTWAIT;
1438 size_t copied;
1439 struct sk_buff *skb, *data_skb;
1440 int err, ret;
1441
1442 if (flags&MSG_OOB)
1443 return -EOPNOTSUPP;
1444
1445 copied = 0;
1446
1447 skb = skb_recv_datagram(sk, flags, noblock, &err);
1448 if (skb == NULL)
1449 goto out;
1450
1451 data_skb = skb;
1452
1453 #ifdef CONFIG_COMPAT_NETLINK_MESSAGES
1454 if (unlikely(skb_shinfo(skb)->frag_list)) {
1455 /*
1456 * If this skb has a frag_list, then here that means that we
1457 * will have to use the frag_list skb's data for compat tasks
1458 * and the regular skb's data for normal (non-compat) tasks.
1459 *
1460 * If we need to send the compat skb, assign it to the
1461 * 'data_skb' variable so that it will be used below for data
1462 * copying. We keep 'skb' for everything else, including
1463 * freeing both later.
1464 */
1465 if (flags & MSG_CMSG_COMPAT)
1466 data_skb = skb_shinfo(skb)->frag_list;
1467 }
1468 #endif
1469
1470 msg->msg_namelen = 0;
1471
1472 copied = data_skb->len;
1473 if (len < copied) {
1474 msg->msg_flags |= MSG_TRUNC;
1475 copied = len;
1476 }
1477
1478 skb_reset_transport_header(data_skb);
1479 err = skb_copy_datagram_iovec(data_skb, 0, msg->msg_iov, copied);
1480
1481 if (msg->msg_name) {
1482 struct sockaddr_nl *addr = (struct sockaddr_nl *)msg->msg_name;
1483 addr->nl_family = AF_NETLINK;
1484 addr->nl_pad = 0;
1485 addr->nl_pid = NETLINK_CB(skb).portid;
1486 addr->nl_groups = netlink_group_mask(NETLINK_CB(skb).dst_group);
1487 msg->msg_namelen = sizeof(*addr);
1488 }
1489
1490 if (nlk->flags & NETLINK_RECV_PKTINFO)
1491 netlink_cmsg_recv_pktinfo(msg, skb);
1492
1493 if (NULL == siocb->scm) {
1494 memset(&scm, 0, sizeof(scm));
1495 siocb->scm = &scm;
1496 }
1497 siocb->scm->creds = *NETLINK_CREDS(skb);
1498 if (flags & MSG_TRUNC)
1499 copied = data_skb->len;
1500
1501 skb_free_datagram(sk, skb);
1502
1503 if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) {
1504 ret = netlink_dump(sk);
1505 if (ret) {
1506 sk->sk_err = ret;
1507 sk->sk_error_report(sk);
1508 }
1509 }
1510
1511 scm_recv(sock, msg, siocb->scm, flags);
1512 out:
1513 netlink_rcv_wake(sk);
1514 return err ? : copied;
1515 }
1516
1517 static void netlink_data_ready(struct sock *sk, int len)
1518 {
1519 BUG();
1520 }
1521
1522 /*
1523 * We export these functions to other modules. They provide a
1524 * complete set of kernel non-blocking support for message
1525 * queueing.
1526 */
1527
1528 struct sock *
1529 __netlink_kernel_create(struct net *net, int unit, struct module *module,
1530 struct netlink_kernel_cfg *cfg)
1531 {
1532 struct socket *sock;
1533 struct sock *sk;
1534 struct netlink_sock *nlk;
1535 struct listeners *listeners = NULL;
1536 struct mutex *cb_mutex = cfg ? cfg->cb_mutex : NULL;
1537 unsigned int groups;
1538
1539 BUG_ON(!nl_table);
1540
1541 if (unit < 0 || unit >= MAX_LINKS)
1542 return NULL;
1543
1544 if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock))
1545 return NULL;
1546
1547 /*
1548 * We have to just have a reference on the net from sk, but don't
1549 * get_net it. Besides, we cannot get and then put the net here.
1550 * So we create one inside init_net and the move it to net.
1551 */
1552
1553 if (__netlink_create(&init_net, sock, cb_mutex, unit) < 0)
1554 goto out_sock_release_nosk;
1555
1556 sk = sock->sk;
1557 sk_change_net(sk, net);
1558
1559 if (!cfg || cfg->groups < 32)
1560 groups = 32;
1561 else
1562 groups = cfg->groups;
1563
1564 listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL);
1565 if (!listeners)
1566 goto out_sock_release;
1567
1568 sk->sk_data_ready = netlink_data_ready;
1569 if (cfg && cfg->input)
1570 nlk_sk(sk)->netlink_rcv = cfg->input;
1571
1572 if (netlink_insert(sk, net, 0))
1573 goto out_sock_release;
1574
1575 nlk = nlk_sk(sk);
1576 nlk->flags |= NETLINK_KERNEL_SOCKET;
1577
1578 netlink_table_grab();
1579 if (!nl_table[unit].registered) {
1580 nl_table[unit].groups = groups;
1581 rcu_assign_pointer(nl_table[unit].listeners, listeners);
1582 nl_table[unit].cb_mutex = cb_mutex;
1583 nl_table[unit].module = module;
1584 if (cfg) {
1585 nl_table[unit].bind = cfg->bind;
1586 nl_table[unit].flags = cfg->flags;
1587 }
1588 nl_table[unit].registered = 1;
1589 } else {
1590 kfree(listeners);
1591 nl_table[unit].registered++;
1592 }
1593 netlink_table_ungrab();
1594 return sk;
1595
1596 out_sock_release:
1597 kfree(listeners);
1598 netlink_kernel_release(sk);
1599 return NULL;
1600
1601 out_sock_release_nosk:
1602 sock_release(sock);
1603 return NULL;
1604 }
1605 EXPORT_SYMBOL(__netlink_kernel_create);
1606
1607 void
1608 netlink_kernel_release(struct sock *sk)
1609 {
1610 sk_release_kernel(sk);
1611 }
1612 EXPORT_SYMBOL(netlink_kernel_release);
1613
1614 int __netlink_change_ngroups(struct sock *sk, unsigned int groups)
1615 {
1616 struct listeners *new, *old;
1617 struct netlink_table *tbl = &nl_table[sk->sk_protocol];
1618
1619 if (groups < 32)
1620 groups = 32;
1621
1622 if (NLGRPSZ(tbl->groups) < NLGRPSZ(groups)) {
1623 new = kzalloc(sizeof(*new) + NLGRPSZ(groups), GFP_ATOMIC);
1624 if (!new)
1625 return -ENOMEM;
1626 old = rcu_dereference_protected(tbl->listeners, 1);
1627 memcpy(new->masks, old->masks, NLGRPSZ(tbl->groups));
1628 rcu_assign_pointer(tbl->listeners, new);
1629
1630 kfree_rcu(old, rcu);
1631 }
1632 tbl->groups = groups;
1633
1634 return 0;
1635 }
1636
1637 /**
1638 * netlink_change_ngroups - change number of multicast groups
1639 *
1640 * This changes the number of multicast groups that are available
1641 * on a certain netlink family. Note that it is not possible to
1642 * change the number of groups to below 32. Also note that it does
1643 * not implicitly call netlink_clear_multicast_users() when the
1644 * number of groups is reduced.
1645 *
1646 * @sk: The kernel netlink socket, as returned by netlink_kernel_create().
1647 * @groups: The new number of groups.
1648 */
1649 int netlink_change_ngroups(struct sock *sk, unsigned int groups)
1650 {
1651 int err;
1652
1653 netlink_table_grab();
1654 err = __netlink_change_ngroups(sk, groups);
1655 netlink_table_ungrab();
1656
1657 return err;
1658 }
1659
1660 void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group)
1661 {
1662 struct sock *sk;
1663 struct hlist_node *node;
1664 struct netlink_table *tbl = &nl_table[ksk->sk_protocol];
1665
1666 sk_for_each_bound(sk, node, &tbl->mc_list)
1667 netlink_update_socket_mc(nlk_sk(sk), group, 0);
1668 }
1669
1670 /**
1671 * netlink_clear_multicast_users - kick off multicast listeners
1672 *
1673 * This function removes all listeners from the given group.
1674 * @ksk: The kernel netlink socket, as returned by
1675 * netlink_kernel_create().
1676 * @group: The multicast group to clear.
1677 */
1678 void netlink_clear_multicast_users(struct sock *ksk, unsigned int group)
1679 {
1680 netlink_table_grab();
1681 __netlink_clear_multicast_users(ksk, group);
1682 netlink_table_ungrab();
1683 }
1684
1685 struct nlmsghdr *
1686 __nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags)
1687 {
1688 struct nlmsghdr *nlh;
1689 int size = NLMSG_LENGTH(len);
1690
1691 nlh = (struct nlmsghdr*)skb_put(skb, NLMSG_ALIGN(size));
1692 nlh->nlmsg_type = type;
1693 nlh->nlmsg_len = size;
1694 nlh->nlmsg_flags = flags;
1695 nlh->nlmsg_pid = portid;
1696 nlh->nlmsg_seq = seq;
1697 if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0)
1698 memset(NLMSG_DATA(nlh) + len, 0, NLMSG_ALIGN(size) - size);
1699 return nlh;
1700 }
1701 EXPORT_SYMBOL(__nlmsg_put);
1702
1703 /*
1704 * It looks a bit ugly.
1705 * It would be better to create kernel thread.
1706 */
1707
1708 static int netlink_dump(struct sock *sk)
1709 {
1710 struct netlink_sock *nlk = nlk_sk(sk);
1711 struct netlink_callback *cb;
1712 struct sk_buff *skb = NULL;
1713 struct nlmsghdr *nlh;
1714 int len, err = -ENOBUFS;
1715 int alloc_size;
1716
1717 mutex_lock(nlk->cb_mutex);
1718
1719 cb = nlk->cb;
1720 if (cb == NULL) {
1721 err = -EINVAL;
1722 goto errout_skb;
1723 }
1724
1725 alloc_size = max_t(int, cb->min_dump_alloc, NLMSG_GOODSIZE);
1726
1727 skb = sock_rmalloc(sk, alloc_size, 0, GFP_KERNEL);
1728 if (!skb)
1729 goto errout_skb;
1730
1731 len = cb->dump(skb, cb);
1732
1733 if (len > 0) {
1734 mutex_unlock(nlk->cb_mutex);
1735
1736 if (sk_filter(sk, skb))
1737 kfree_skb(skb);
1738 else
1739 __netlink_sendskb(sk, skb);
1740 return 0;
1741 }
1742
1743 nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI);
1744 if (!nlh)
1745 goto errout_skb;
1746
1747 nl_dump_check_consistent(cb, nlh);
1748
1749 memcpy(nlmsg_data(nlh), &len, sizeof(len));
1750
1751 if (sk_filter(sk, skb))
1752 kfree_skb(skb);
1753 else
1754 __netlink_sendskb(sk, skb);
1755
1756 if (cb->done)
1757 cb->done(cb);
1758 nlk->cb = NULL;
1759 mutex_unlock(nlk->cb_mutex);
1760
1761 netlink_consume_callback(cb);
1762 return 0;
1763
1764 errout_skb:
1765 mutex_unlock(nlk->cb_mutex);
1766 kfree_skb(skb);
1767 return err;
1768 }
1769
1770 int netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
1771 const struct nlmsghdr *nlh,
1772 struct netlink_dump_control *control)
1773 {
1774 struct netlink_callback *cb;
1775 struct sock *sk;
1776 struct netlink_sock *nlk;
1777 int ret;
1778
1779 cb = kzalloc(sizeof(*cb), GFP_KERNEL);
1780 if (cb == NULL)
1781 return -ENOBUFS;
1782
1783 cb->dump = control->dump;
1784 cb->done = control->done;
1785 cb->nlh = nlh;
1786 cb->data = control->data;
1787 cb->min_dump_alloc = control->min_dump_alloc;
1788 atomic_inc(&skb->users);
1789 cb->skb = skb;
1790
1791 sk = netlink_lookup(sock_net(ssk), ssk->sk_protocol, NETLINK_CB(skb).portid);
1792 if (sk == NULL) {
1793 netlink_destroy_callback(cb);
1794 return -ECONNREFUSED;
1795 }
1796 nlk = nlk_sk(sk);
1797 /* A dump is in progress... */
1798 mutex_lock(nlk->cb_mutex);
1799 if (nlk->cb) {
1800 mutex_unlock(nlk->cb_mutex);
1801 netlink_destroy_callback(cb);
1802 sock_put(sk);
1803 return -EBUSY;
1804 }
1805 nlk->cb = cb;
1806 mutex_unlock(nlk->cb_mutex);
1807
1808 ret = netlink_dump(sk);
1809
1810 sock_put(sk);
1811
1812 if (ret)
1813 return ret;
1814
1815 /* We successfully started a dump, by returning -EINTR we
1816 * signal not to send ACK even if it was requested.
1817 */
1818 return -EINTR;
1819 }
1820 EXPORT_SYMBOL(netlink_dump_start);
1821
1822 void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err)
1823 {
1824 struct sk_buff *skb;
1825 struct nlmsghdr *rep;
1826 struct nlmsgerr *errmsg;
1827 size_t payload = sizeof(*errmsg);
1828
1829 /* error messages get the original request appened */
1830 if (err)
1831 payload += nlmsg_len(nlh);
1832
1833 skb = nlmsg_new(payload, GFP_KERNEL);
1834 if (!skb) {
1835 struct sock *sk;
1836
1837 sk = netlink_lookup(sock_net(in_skb->sk),
1838 in_skb->sk->sk_protocol,
1839 NETLINK_CB(in_skb).portid);
1840 if (sk) {
1841 sk->sk_err = ENOBUFS;
1842 sk->sk_error_report(sk);
1843 sock_put(sk);
1844 }
1845 return;
1846 }
1847
1848 rep = __nlmsg_put(skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq,
1849 NLMSG_ERROR, payload, 0);
1850 errmsg = nlmsg_data(rep);
1851 errmsg->error = err;
1852 memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(*nlh));
1853 netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).portid, MSG_DONTWAIT);
1854 }
1855 EXPORT_SYMBOL(netlink_ack);
1856
1857 int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *,
1858 struct nlmsghdr *))
1859 {
1860 struct nlmsghdr *nlh;
1861 int err;
1862
1863 while (skb->len >= nlmsg_total_size(0)) {
1864 int msglen;
1865
1866 nlh = nlmsg_hdr(skb);
1867 err = 0;
1868
1869 if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len)
1870 return 0;
1871
1872 /* Only requests are handled by the kernel */
1873 if (!(nlh->nlmsg_flags & NLM_F_REQUEST))
1874 goto ack;
1875
1876 /* Skip control messages */
1877 if (nlh->nlmsg_type < NLMSG_MIN_TYPE)
1878 goto ack;
1879
1880 err = cb(skb, nlh);
1881 if (err == -EINTR)
1882 goto skip;
1883
1884 ack:
1885 if (nlh->nlmsg_flags & NLM_F_ACK || err)
1886 netlink_ack(skb, nlh, err);
1887
1888 skip:
1889 msglen = NLMSG_ALIGN(nlh->nlmsg_len);
1890 if (msglen > skb->len)
1891 msglen = skb->len;
1892 skb_pull(skb, msglen);
1893 }
1894
1895 return 0;
1896 }
1897 EXPORT_SYMBOL(netlink_rcv_skb);
1898
1899 /**
1900 * nlmsg_notify - send a notification netlink message
1901 * @sk: netlink socket to use
1902 * @skb: notification message
1903 * @portid: destination netlink portid for reports or 0
1904 * @group: destination multicast group or 0
1905 * @report: 1 to report back, 0 to disable
1906 * @flags: allocation flags
1907 */
1908 int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid,
1909 unsigned int group, int report, gfp_t flags)
1910 {
1911 int err = 0;
1912
1913 if (group) {
1914 int exclude_portid = 0;
1915
1916 if (report) {
1917 atomic_inc(&skb->users);
1918 exclude_portid = portid;
1919 }
1920
1921 /* errors reported via destination sk->sk_err, but propagate
1922 * delivery errors if NETLINK_BROADCAST_ERROR flag is set */
1923 err = nlmsg_multicast(sk, skb, exclude_portid, group, flags);
1924 }
1925
1926 if (report) {
1927 int err2;
1928
1929 err2 = nlmsg_unicast(sk, skb, portid);
1930 if (!err || err == -ESRCH)
1931 err = err2;
1932 }
1933
1934 return err;
1935 }
1936 EXPORT_SYMBOL(nlmsg_notify);
1937
1938 #ifdef CONFIG_PROC_FS
1939 struct nl_seq_iter {
1940 struct seq_net_private p;
1941 int link;
1942 int hash_idx;
1943 };
1944
1945 static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos)
1946 {
1947 struct nl_seq_iter *iter = seq->private;
1948 int i, j;
1949 struct sock *s;
1950 struct hlist_node *node;
1951 loff_t off = 0;
1952
1953 for (i = 0; i < MAX_LINKS; i++) {
1954 struct nl_portid_hash *hash = &nl_table[i].hash;
1955
1956 for (j = 0; j <= hash->mask; j++) {
1957 sk_for_each(s, node, &hash->table[j]) {
1958 if (sock_net(s) != seq_file_net(seq))
1959 continue;
1960 if (off == pos) {
1961 iter->link = i;
1962 iter->hash_idx = j;
1963 return s;
1964 }
1965 ++off;
1966 }
1967 }
1968 }
1969 return NULL;
1970 }
1971
1972 static void *netlink_seq_start(struct seq_file *seq, loff_t *pos)
1973 __acquires(nl_table_lock)
1974 {
1975 read_lock(&nl_table_lock);
1976 return *pos ? netlink_seq_socket_idx(seq, *pos - 1) : SEQ_START_TOKEN;
1977 }
1978
1979 static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1980 {
1981 struct sock *s;
1982 struct nl_seq_iter *iter;
1983 int i, j;
1984
1985 ++*pos;
1986
1987 if (v == SEQ_START_TOKEN)
1988 return netlink_seq_socket_idx(seq, 0);
1989
1990 iter = seq->private;
1991 s = v;
1992 do {
1993 s = sk_next(s);
1994 } while (s && sock_net(s) != seq_file_net(seq));
1995 if (s)
1996 return s;
1997
1998 i = iter->link;
1999 j = iter->hash_idx + 1;
2000
2001 do {
2002 struct nl_portid_hash *hash = &nl_table[i].hash;
2003
2004 for (; j <= hash->mask; j++) {
2005 s = sk_head(&hash->table[j]);
2006 while (s && sock_net(s) != seq_file_net(seq))
2007 s = sk_next(s);
2008 if (s) {
2009 iter->link = i;
2010 iter->hash_idx = j;
2011 return s;
2012 }
2013 }
2014
2015 j = 0;
2016 } while (++i < MAX_LINKS);
2017
2018 return NULL;
2019 }
2020
2021 static void netlink_seq_stop(struct seq_file *seq, void *v)
2022 __releases(nl_table_lock)
2023 {
2024 read_unlock(&nl_table_lock);
2025 }
2026
2027
2028 static int netlink_seq_show(struct seq_file *seq, void *v)
2029 {
2030 if (v == SEQ_START_TOKEN) {
2031 seq_puts(seq,
2032 "sk Eth Pid Groups "
2033 "Rmem Wmem Dump Locks Drops Inode\n");
2034 } else {
2035 struct sock *s = v;
2036 struct netlink_sock *nlk = nlk_sk(s);
2037
2038 seq_printf(seq, "%pK %-3d %-6d %08x %-8d %-8d %pK %-8d %-8d %-8lu\n",
2039 s,
2040 s->sk_protocol,
2041 nlk->portid,
2042 nlk->groups ? (u32)nlk->groups[0] : 0,
2043 sk_rmem_alloc_get(s),
2044 sk_wmem_alloc_get(s),
2045 nlk->cb,
2046 atomic_read(&s->sk_refcnt),
2047 atomic_read(&s->sk_drops),
2048 sock_i_ino(s)
2049 );
2050
2051 }
2052 return 0;
2053 }
2054
2055 static const struct seq_operations netlink_seq_ops = {
2056 .start = netlink_seq_start,
2057 .next = netlink_seq_next,
2058 .stop = netlink_seq_stop,
2059 .show = netlink_seq_show,
2060 };
2061
2062
2063 static int netlink_seq_open(struct inode *inode, struct file *file)
2064 {
2065 return seq_open_net(inode, file, &netlink_seq_ops,
2066 sizeof(struct nl_seq_iter));
2067 }
2068
2069 static const struct file_operations netlink_seq_fops = {
2070 .owner = THIS_MODULE,
2071 .open = netlink_seq_open,
2072 .read = seq_read,
2073 .llseek = seq_lseek,
2074 .release = seq_release_net,
2075 };
2076
2077 #endif
2078
2079 int netlink_register_notifier(struct notifier_block *nb)
2080 {
2081 return atomic_notifier_chain_register(&netlink_chain, nb);
2082 }
2083 EXPORT_SYMBOL(netlink_register_notifier);
2084
2085 int netlink_unregister_notifier(struct notifier_block *nb)
2086 {
2087 return atomic_notifier_chain_unregister(&netlink_chain, nb);
2088 }
2089 EXPORT_SYMBOL(netlink_unregister_notifier);
2090
2091 static const struct proto_ops netlink_ops = {
2092 .family = PF_NETLINK,
2093 .owner = THIS_MODULE,
2094 .release = netlink_release,
2095 .bind = netlink_bind,
2096 .connect = netlink_connect,
2097 .socketpair = sock_no_socketpair,
2098 .accept = sock_no_accept,
2099 .getname = netlink_getname,
2100 .poll = datagram_poll,
2101 .ioctl = sock_no_ioctl,
2102 .listen = sock_no_listen,
2103 .shutdown = sock_no_shutdown,
2104 .setsockopt = netlink_setsockopt,
2105 .getsockopt = netlink_getsockopt,
2106 .sendmsg = netlink_sendmsg,
2107 .recvmsg = netlink_recvmsg,
2108 .mmap = sock_no_mmap,
2109 .sendpage = sock_no_sendpage,
2110 };
2111
2112 static const struct net_proto_family netlink_family_ops = {
2113 .family = PF_NETLINK,
2114 .create = netlink_create,
2115 .owner = THIS_MODULE, /* for consistency 8) */
2116 };
2117
2118 static int __net_init netlink_net_init(struct net *net)
2119 {
2120 #ifdef CONFIG_PROC_FS
2121 if (!proc_net_fops_create(net, "netlink", 0, &netlink_seq_fops))
2122 return -ENOMEM;
2123 #endif
2124 return 0;
2125 }
2126
2127 static void __net_exit netlink_net_exit(struct net *net)
2128 {
2129 #ifdef CONFIG_PROC_FS
2130 proc_net_remove(net, "netlink");
2131 #endif
2132 }
2133
2134 static void __init netlink_add_usersock_entry(void)
2135 {
2136 struct listeners *listeners;
2137 int groups = 32;
2138
2139 listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL);
2140 if (!listeners)
2141 panic("netlink_add_usersock_entry: Cannot allocate listeners\n");
2142
2143 netlink_table_grab();
2144
2145 nl_table[NETLINK_USERSOCK].groups = groups;
2146 rcu_assign_pointer(nl_table[NETLINK_USERSOCK].listeners, listeners);
2147 nl_table[NETLINK_USERSOCK].module = THIS_MODULE;
2148 nl_table[NETLINK_USERSOCK].registered = 1;
2149 nl_table[NETLINK_USERSOCK].flags = NL_CFG_F_NONROOT_SEND;
2150
2151 netlink_table_ungrab();
2152 }
2153
2154 static struct pernet_operations __net_initdata netlink_net_ops = {
2155 .init = netlink_net_init,
2156 .exit = netlink_net_exit,
2157 };
2158
2159 static int __init netlink_proto_init(void)
2160 {
2161 struct sk_buff *dummy_skb;
2162 int i;
2163 unsigned long limit;
2164 unsigned int order;
2165 int err = proto_register(&netlink_proto, 0);
2166
2167 if (err != 0)
2168 goto out;
2169
2170 BUILD_BUG_ON(sizeof(struct netlink_skb_parms) > sizeof(dummy_skb->cb));
2171
2172 nl_table = kcalloc(MAX_LINKS, sizeof(*nl_table), GFP_KERNEL);
2173 if (!nl_table)
2174 goto panic;
2175
2176 if (totalram_pages >= (128 * 1024))
2177 limit = totalram_pages >> (21 - PAGE_SHIFT);
2178 else
2179 limit = totalram_pages >> (23 - PAGE_SHIFT);
2180
2181 order = get_bitmask_order(limit) - 1 + PAGE_SHIFT;
2182 limit = (1UL << order) / sizeof(struct hlist_head);
2183 order = get_bitmask_order(min(limit, (unsigned long)UINT_MAX)) - 1;
2184
2185 for (i = 0; i < MAX_LINKS; i++) {
2186 struct nl_portid_hash *hash = &nl_table[i].hash;
2187
2188 hash->table = nl_portid_hash_zalloc(1 * sizeof(*hash->table));
2189 if (!hash->table) {
2190 while (i-- > 0)
2191 nl_portid_hash_free(nl_table[i].hash.table,
2192 1 * sizeof(*hash->table));
2193 kfree(nl_table);
2194 goto panic;
2195 }
2196 hash->max_shift = order;
2197 hash->shift = 0;
2198 hash->mask = 0;
2199 hash->rehash_time = jiffies;
2200 }
2201
2202 netlink_add_usersock_entry();
2203
2204 sock_register(&netlink_family_ops);
2205 register_pernet_subsys(&netlink_net_ops);
2206 /* The netlink device handler may be needed early. */
2207 rtnetlink_init();
2208 out:
2209 return err;
2210 panic:
2211 panic("netlink_init: Cannot allocate nl_table\n");
2212 }
2213
2214 core_initcall(netlink_proto_init);
kernel source for telekom puls (alcatel/mediatek)