Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * NETLINK Kernel-user communication protocol. | |
3 | * | |
113aa838 | 4 | * Authors: Alan Cox <alan@lxorguk.ukuu.org.uk> |
1da177e4 | 5 | * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> |
cd1df525 | 6 | * Patrick McHardy <kaber@trash.net> |
1da177e4 LT |
7 | * |
8 | * This program is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU General Public License | |
10 | * as published by the Free Software Foundation; either version | |
11 | * 2 of the License, or (at your option) any later version. | |
746fac4d | 12 | * |
1da177e4 LT |
13 | * Tue Jun 26 14:36:48 MEST 2001 Herbert "herp" Rosmanith |
14 | * added netlink_proto_exit | |
15 | * Tue Jan 22 18:32:44 BRST 2002 Arnaldo C. de Melo <acme@conectiva.com.br> | |
16 | * use nlk_sk, as sk->protinfo is on a diet 8) | |
4fdb3bb7 HW |
17 | * Fri Jul 22 19:51:12 MEST 2005 Harald Welte <laforge@gnumonks.org> |
18 | * - inc module use count of module that owns | |
19 | * the kernel socket in case userspace opens | |
20 | * socket of same protocol | |
21 | * - remove all module support, since netlink is | |
22 | * mandatory if CONFIG_NET=y these days | |
1da177e4 LT |
23 | */ |
24 | ||
1da177e4 LT |
25 | #include <linux/module.h> |
26 | ||
4fc268d2 | 27 | #include <linux/capability.h> |
1da177e4 LT |
28 | #include <linux/kernel.h> |
29 | #include <linux/init.h> | |
1da177e4 LT |
30 | #include <linux/signal.h> |
31 | #include <linux/sched.h> | |
32 | #include <linux/errno.h> | |
33 | #include <linux/string.h> | |
34 | #include <linux/stat.h> | |
35 | #include <linux/socket.h> | |
36 | #include <linux/un.h> | |
37 | #include <linux/fcntl.h> | |
38 | #include <linux/termios.h> | |
39 | #include <linux/sockios.h> | |
40 | #include <linux/net.h> | |
41 | #include <linux/fs.h> | |
42 | #include <linux/slab.h> | |
43 | #include <asm/uaccess.h> | |
44 | #include <linux/skbuff.h> | |
45 | #include <linux/netdevice.h> | |
46 | #include <linux/rtnetlink.h> | |
47 | #include <linux/proc_fs.h> | |
48 | #include <linux/seq_file.h> | |
1da177e4 LT |
49 | #include <linux/notifier.h> |
50 | #include <linux/security.h> | |
51 | #include <linux/jhash.h> | |
52 | #include <linux/jiffies.h> | |
53 | #include <linux/random.h> | |
54 | #include <linux/bitops.h> | |
55 | #include <linux/mm.h> | |
56 | #include <linux/types.h> | |
54e0f520 | 57 | #include <linux/audit.h> |
af65bdfc | 58 | #include <linux/mutex.h> |
ccdfcc39 | 59 | #include <linux/vmalloc.h> |
bcbde0d4 | 60 | #include <linux/if_arp.h> |
e341694e | 61 | #include <linux/rhashtable.h> |
9652e931 | 62 | #include <asm/cacheflush.h> |
e341694e | 63 | #include <linux/hash.h> |
54e0f520 | 64 | |
457c4cbc | 65 | #include <net/net_namespace.h> |
1da177e4 LT |
66 | #include <net/sock.h> |
67 | #include <net/scm.h> | |
82ace47a | 68 | #include <net/netlink.h> |
1da177e4 | 69 | |
0f29c768 | 70 | #include "af_netlink.h" |
1da177e4 | 71 | |
5c398dc8 ED |
72 | struct listeners { |
73 | struct rcu_head rcu; | |
74 | unsigned long masks[0]; | |
6c04bb18 JB |
75 | }; |
76 | ||
cd967e05 PM |
77 | /* state bits */ |
78 | #define NETLINK_CONGESTED 0x0 | |
79 | ||
80 | /* flags */ | |
77247bbb | 81 | #define NETLINK_KERNEL_SOCKET 0x1 |
9a4595bc | 82 | #define NETLINK_RECV_PKTINFO 0x2 |
be0c22a4 | 83 | #define NETLINK_BROADCAST_SEND_ERROR 0x4 |
38938bfe | 84 | #define NETLINK_RECV_NO_ENOBUFS 0x8 |
77247bbb | 85 | |
035c4c16 | 86 | static inline int netlink_is_kernel(struct sock *sk) |
aed81560 DL |
87 | { |
88 | return nlk_sk(sk)->flags & NETLINK_KERNEL_SOCKET; | |
89 | } | |
90 | ||
0f29c768 AV |
91 | struct netlink_table *nl_table; |
92 | EXPORT_SYMBOL_GPL(nl_table); | |
1da177e4 LT |
93 | |
94 | static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait); | |
95 | ||
96 | static int netlink_dump(struct sock *sk); | |
9652e931 | 97 | static void netlink_skb_destructor(struct sk_buff *skb); |
1da177e4 | 98 | |
0f29c768 AV |
99 | DEFINE_RWLOCK(nl_table_lock); |
100 | EXPORT_SYMBOL_GPL(nl_table_lock); | |
1da177e4 LT |
101 | static atomic_t nl_table_users = ATOMIC_INIT(0); |
102 | ||
6d772ac5 ED |
103 | #define nl_deref_protected(X) rcu_dereference_protected(X, lockdep_is_held(&nl_table_lock)); |
104 | ||
e341694e TG |
105 | /* Protects netlink socket hash table mutations */ |
106 | DEFINE_MUTEX(nl_sk_hash_lock); | |
6c8f7e70 | 107 | EXPORT_SYMBOL_GPL(nl_sk_hash_lock); |
e341694e TG |
108 | |
109 | static int lockdep_nl_sk_hash_is_held(void) | |
110 | { | |
111 | #ifdef CONFIG_LOCKDEP | |
112 | return (debug_locks) ? lockdep_is_held(&nl_sk_hash_lock) : 1; | |
113 | #else | |
114 | return 1; | |
115 | #endif | |
116 | } | |
117 | ||
e041c683 | 118 | static ATOMIC_NOTIFIER_HEAD(netlink_chain); |
1da177e4 | 119 | |
bcbde0d4 DB |
120 | static DEFINE_SPINLOCK(netlink_tap_lock); |
121 | static struct list_head netlink_tap_all __read_mostly; | |
122 | ||
b57ef81f | 123 | static inline u32 netlink_group_mask(u32 group) |
d629b836 PM |
124 | { |
125 | return group ? 1 << (group - 1) : 0; | |
126 | } | |
127 | ||
bcbde0d4 DB |
128 | int netlink_add_tap(struct netlink_tap *nt) |
129 | { | |
130 | if (unlikely(nt->dev->type != ARPHRD_NETLINK)) | |
131 | return -EINVAL; | |
132 | ||
133 | spin_lock(&netlink_tap_lock); | |
134 | list_add_rcu(&nt->list, &netlink_tap_all); | |
135 | spin_unlock(&netlink_tap_lock); | |
136 | ||
137 | if (nt->module) | |
138 | __module_get(nt->module); | |
139 | ||
140 | return 0; | |
141 | } | |
142 | EXPORT_SYMBOL_GPL(netlink_add_tap); | |
143 | ||
2173f8d9 | 144 | static int __netlink_remove_tap(struct netlink_tap *nt) |
bcbde0d4 DB |
145 | { |
146 | bool found = false; | |
147 | struct netlink_tap *tmp; | |
148 | ||
149 | spin_lock(&netlink_tap_lock); | |
150 | ||
151 | list_for_each_entry(tmp, &netlink_tap_all, list) { | |
152 | if (nt == tmp) { | |
153 | list_del_rcu(&nt->list); | |
154 | found = true; | |
155 | goto out; | |
156 | } | |
157 | } | |
158 | ||
159 | pr_warn("__netlink_remove_tap: %p not found\n", nt); | |
160 | out: | |
161 | spin_unlock(&netlink_tap_lock); | |
162 | ||
163 | if (found && nt->module) | |
164 | module_put(nt->module); | |
165 | ||
166 | return found ? 0 : -ENODEV; | |
167 | } | |
bcbde0d4 DB |
168 | |
169 | int netlink_remove_tap(struct netlink_tap *nt) | |
170 | { | |
171 | int ret; | |
172 | ||
173 | ret = __netlink_remove_tap(nt); | |
174 | synchronize_net(); | |
175 | ||
176 | return ret; | |
177 | } | |
178 | EXPORT_SYMBOL_GPL(netlink_remove_tap); | |
179 | ||
5ffd5cdd DB |
180 | static bool netlink_filter_tap(const struct sk_buff *skb) |
181 | { | |
182 | struct sock *sk = skb->sk; | |
5ffd5cdd DB |
183 | |
184 | /* We take the more conservative approach and | |
185 | * whitelist socket protocols that may pass. | |
186 | */ | |
187 | switch (sk->sk_protocol) { | |
188 | case NETLINK_ROUTE: | |
189 | case NETLINK_USERSOCK: | |
190 | case NETLINK_SOCK_DIAG: | |
191 | case NETLINK_NFLOG: | |
192 | case NETLINK_XFRM: | |
193 | case NETLINK_FIB_LOOKUP: | |
194 | case NETLINK_NETFILTER: | |
195 | case NETLINK_GENERIC: | |
498044bb | 196 | return true; |
5ffd5cdd DB |
197 | } |
198 | ||
498044bb | 199 | return false; |
5ffd5cdd DB |
200 | } |
201 | ||
bcbde0d4 DB |
202 | static int __netlink_deliver_tap_skb(struct sk_buff *skb, |
203 | struct net_device *dev) | |
204 | { | |
205 | struct sk_buff *nskb; | |
5ffd5cdd | 206 | struct sock *sk = skb->sk; |
bcbde0d4 DB |
207 | int ret = -ENOMEM; |
208 | ||
209 | dev_hold(dev); | |
210 | nskb = skb_clone(skb, GFP_ATOMIC); | |
211 | if (nskb) { | |
212 | nskb->dev = dev; | |
5ffd5cdd | 213 | nskb->protocol = htons((u16) sk->sk_protocol); |
604d13c9 DB |
214 | nskb->pkt_type = netlink_is_kernel(sk) ? |
215 | PACKET_KERNEL : PACKET_USER; | |
4e48ed88 | 216 | skb_reset_network_header(nskb); |
bcbde0d4 DB |
217 | ret = dev_queue_xmit(nskb); |
218 | if (unlikely(ret > 0)) | |
219 | ret = net_xmit_errno(ret); | |
220 | } | |
221 | ||
222 | dev_put(dev); | |
223 | return ret; | |
224 | } | |
225 | ||
226 | static void __netlink_deliver_tap(struct sk_buff *skb) | |
227 | { | |
228 | int ret; | |
229 | struct netlink_tap *tmp; | |
230 | ||
5ffd5cdd DB |
231 | if (!netlink_filter_tap(skb)) |
232 | return; | |
233 | ||
bcbde0d4 DB |
234 | list_for_each_entry_rcu(tmp, &netlink_tap_all, list) { |
235 | ret = __netlink_deliver_tap_skb(skb, tmp->dev); | |
236 | if (unlikely(ret)) | |
237 | break; | |
238 | } | |
239 | } | |
240 | ||
241 | static void netlink_deliver_tap(struct sk_buff *skb) | |
242 | { | |
243 | rcu_read_lock(); | |
244 | ||
245 | if (unlikely(!list_empty(&netlink_tap_all))) | |
246 | __netlink_deliver_tap(skb); | |
247 | ||
248 | rcu_read_unlock(); | |
249 | } | |
250 | ||
73bfd370 DB |
251 | static void netlink_deliver_tap_kernel(struct sock *dst, struct sock *src, |
252 | struct sk_buff *skb) | |
253 | { | |
254 | if (!(netlink_is_kernel(dst) && netlink_is_kernel(src))) | |
255 | netlink_deliver_tap(skb); | |
256 | } | |
257 | ||
cd1df525 PM |
258 | static void netlink_overrun(struct sock *sk) |
259 | { | |
260 | struct netlink_sock *nlk = nlk_sk(sk); | |
261 | ||
262 | if (!(nlk->flags & NETLINK_RECV_NO_ENOBUFS)) { | |
263 | if (!test_and_set_bit(NETLINK_CONGESTED, &nlk_sk(sk)->state)) { | |
264 | sk->sk_err = ENOBUFS; | |
265 | sk->sk_error_report(sk); | |
266 | } | |
267 | } | |
268 | atomic_inc(&sk->sk_drops); | |
269 | } | |
270 | ||
271 | static void netlink_rcv_wake(struct sock *sk) | |
272 | { | |
273 | struct netlink_sock *nlk = nlk_sk(sk); | |
274 | ||
275 | if (skb_queue_empty(&sk->sk_receive_queue)) | |
276 | clear_bit(NETLINK_CONGESTED, &nlk->state); | |
277 | if (!test_bit(NETLINK_CONGESTED, &nlk->state)) | |
278 | wake_up_interruptible(&nlk->wait); | |
279 | } | |
280 | ||
ccdfcc39 | 281 | #ifdef CONFIG_NETLINK_MMAP |
9652e931 PM |
282 | static bool netlink_skb_is_mmaped(const struct sk_buff *skb) |
283 | { | |
284 | return NETLINK_CB(skb).flags & NETLINK_SKB_MMAPED; | |
285 | } | |
286 | ||
f9c22888 PM |
287 | static bool netlink_rx_is_mmaped(struct sock *sk) |
288 | { | |
289 | return nlk_sk(sk)->rx_ring.pg_vec != NULL; | |
290 | } | |
291 | ||
5fd96123 PM |
292 | static bool netlink_tx_is_mmaped(struct sock *sk) |
293 | { | |
294 | return nlk_sk(sk)->tx_ring.pg_vec != NULL; | |
295 | } | |
296 | ||
ccdfcc39 PM |
297 | static __pure struct page *pgvec_to_page(const void *addr) |
298 | { | |
299 | if (is_vmalloc_addr(addr)) | |
300 | return vmalloc_to_page(addr); | |
301 | else | |
302 | return virt_to_page(addr); | |
303 | } | |
304 | ||
305 | static void free_pg_vec(void **pg_vec, unsigned int order, unsigned int len) | |
306 | { | |
307 | unsigned int i; | |
308 | ||
309 | for (i = 0; i < len; i++) { | |
310 | if (pg_vec[i] != NULL) { | |
311 | if (is_vmalloc_addr(pg_vec[i])) | |
312 | vfree(pg_vec[i]); | |
313 | else | |
314 | free_pages((unsigned long)pg_vec[i], order); | |
315 | } | |
316 | } | |
317 | kfree(pg_vec); | |
318 | } | |
319 | ||
320 | static void *alloc_one_pg_vec_page(unsigned long order) | |
321 | { | |
322 | void *buffer; | |
323 | gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP | __GFP_ZERO | | |
324 | __GFP_NOWARN | __GFP_NORETRY; | |
325 | ||
326 | buffer = (void *)__get_free_pages(gfp_flags, order); | |
327 | if (buffer != NULL) | |
328 | return buffer; | |
329 | ||
330 | buffer = vzalloc((1 << order) * PAGE_SIZE); | |
331 | if (buffer != NULL) | |
332 | return buffer; | |
333 | ||
334 | gfp_flags &= ~__GFP_NORETRY; | |
335 | return (void *)__get_free_pages(gfp_flags, order); | |
336 | } | |
337 | ||
338 | static void **alloc_pg_vec(struct netlink_sock *nlk, | |
339 | struct nl_mmap_req *req, unsigned int order) | |
340 | { | |
341 | unsigned int block_nr = req->nm_block_nr; | |
342 | unsigned int i; | |
8a849bb7 | 343 | void **pg_vec; |
ccdfcc39 PM |
344 | |
345 | pg_vec = kcalloc(block_nr, sizeof(void *), GFP_KERNEL); | |
346 | if (pg_vec == NULL) | |
347 | return NULL; | |
348 | ||
349 | for (i = 0; i < block_nr; i++) { | |
8a849bb7 | 350 | pg_vec[i] = alloc_one_pg_vec_page(order); |
ccdfcc39 PM |
351 | if (pg_vec[i] == NULL) |
352 | goto err1; | |
353 | } | |
354 | ||
355 | return pg_vec; | |
356 | err1: | |
357 | free_pg_vec(pg_vec, order, block_nr); | |
358 | return NULL; | |
359 | } | |
360 | ||
361 | static int netlink_set_ring(struct sock *sk, struct nl_mmap_req *req, | |
362 | bool closing, bool tx_ring) | |
363 | { | |
364 | struct netlink_sock *nlk = nlk_sk(sk); | |
365 | struct netlink_ring *ring; | |
366 | struct sk_buff_head *queue; | |
367 | void **pg_vec = NULL; | |
368 | unsigned int order = 0; | |
369 | int err; | |
370 | ||
371 | ring = tx_ring ? &nlk->tx_ring : &nlk->rx_ring; | |
372 | queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue; | |
373 | ||
374 | if (!closing) { | |
375 | if (atomic_read(&nlk->mapped)) | |
376 | return -EBUSY; | |
377 | if (atomic_read(&ring->pending)) | |
378 | return -EBUSY; | |
379 | } | |
380 | ||
381 | if (req->nm_block_nr) { | |
382 | if (ring->pg_vec != NULL) | |
383 | return -EBUSY; | |
384 | ||
385 | if ((int)req->nm_block_size <= 0) | |
386 | return -EINVAL; | |
74e83b23 | 387 | if (!PAGE_ALIGNED(req->nm_block_size)) |
ccdfcc39 PM |
388 | return -EINVAL; |
389 | if (req->nm_frame_size < NL_MMAP_HDRLEN) | |
390 | return -EINVAL; | |
391 | if (!IS_ALIGNED(req->nm_frame_size, NL_MMAP_MSG_ALIGNMENT)) | |
392 | return -EINVAL; | |
393 | ||
394 | ring->frames_per_block = req->nm_block_size / | |
395 | req->nm_frame_size; | |
396 | if (ring->frames_per_block == 0) | |
397 | return -EINVAL; | |
398 | if (ring->frames_per_block * req->nm_block_nr != | |
399 | req->nm_frame_nr) | |
400 | return -EINVAL; | |
401 | ||
402 | order = get_order(req->nm_block_size); | |
403 | pg_vec = alloc_pg_vec(nlk, req, order); | |
404 | if (pg_vec == NULL) | |
405 | return -ENOMEM; | |
406 | } else { | |
407 | if (req->nm_frame_nr) | |
408 | return -EINVAL; | |
409 | } | |
410 | ||
411 | err = -EBUSY; | |
412 | mutex_lock(&nlk->pg_vec_lock); | |
413 | if (closing || atomic_read(&nlk->mapped) == 0) { | |
414 | err = 0; | |
415 | spin_lock_bh(&queue->lock); | |
416 | ||
417 | ring->frame_max = req->nm_frame_nr - 1; | |
418 | ring->head = 0; | |
419 | ring->frame_size = req->nm_frame_size; | |
420 | ring->pg_vec_pages = req->nm_block_size / PAGE_SIZE; | |
421 | ||
422 | swap(ring->pg_vec_len, req->nm_block_nr); | |
423 | swap(ring->pg_vec_order, order); | |
424 | swap(ring->pg_vec, pg_vec); | |
425 | ||
426 | __skb_queue_purge(queue); | |
427 | spin_unlock_bh(&queue->lock); | |
428 | ||
429 | WARN_ON(atomic_read(&nlk->mapped)); | |
430 | } | |
431 | mutex_unlock(&nlk->pg_vec_lock); | |
432 | ||
433 | if (pg_vec) | |
434 | free_pg_vec(pg_vec, order, req->nm_block_nr); | |
435 | return err; | |
436 | } | |
437 | ||
438 | static void netlink_mm_open(struct vm_area_struct *vma) | |
439 | { | |
440 | struct file *file = vma->vm_file; | |
441 | struct socket *sock = file->private_data; | |
442 | struct sock *sk = sock->sk; | |
443 | ||
444 | if (sk) | |
445 | atomic_inc(&nlk_sk(sk)->mapped); | |
446 | } | |
447 | ||
448 | static void netlink_mm_close(struct vm_area_struct *vma) | |
449 | { | |
450 | struct file *file = vma->vm_file; | |
451 | struct socket *sock = file->private_data; | |
452 | struct sock *sk = sock->sk; | |
453 | ||
454 | if (sk) | |
455 | atomic_dec(&nlk_sk(sk)->mapped); | |
456 | } | |
457 | ||
458 | static const struct vm_operations_struct netlink_mmap_ops = { | |
459 | .open = netlink_mm_open, | |
460 | .close = netlink_mm_close, | |
461 | }; | |
462 | ||
463 | static int netlink_mmap(struct file *file, struct socket *sock, | |
464 | struct vm_area_struct *vma) | |
465 | { | |
466 | struct sock *sk = sock->sk; | |
467 | struct netlink_sock *nlk = nlk_sk(sk); | |
468 | struct netlink_ring *ring; | |
469 | unsigned long start, size, expected; | |
470 | unsigned int i; | |
471 | int err = -EINVAL; | |
472 | ||
473 | if (vma->vm_pgoff) | |
474 | return -EINVAL; | |
475 | ||
476 | mutex_lock(&nlk->pg_vec_lock); | |
477 | ||
478 | expected = 0; | |
479 | for (ring = &nlk->rx_ring; ring <= &nlk->tx_ring; ring++) { | |
480 | if (ring->pg_vec == NULL) | |
481 | continue; | |
482 | expected += ring->pg_vec_len * ring->pg_vec_pages * PAGE_SIZE; | |
483 | } | |
484 | ||
485 | if (expected == 0) | |
486 | goto out; | |
487 | ||
488 | size = vma->vm_end - vma->vm_start; | |
489 | if (size != expected) | |
490 | goto out; | |
491 | ||
492 | start = vma->vm_start; | |
493 | for (ring = &nlk->rx_ring; ring <= &nlk->tx_ring; ring++) { | |
494 | if (ring->pg_vec == NULL) | |
495 | continue; | |
496 | ||
497 | for (i = 0; i < ring->pg_vec_len; i++) { | |
498 | struct page *page; | |
499 | void *kaddr = ring->pg_vec[i]; | |
500 | unsigned int pg_num; | |
501 | ||
502 | for (pg_num = 0; pg_num < ring->pg_vec_pages; pg_num++) { | |
503 | page = pgvec_to_page(kaddr); | |
504 | err = vm_insert_page(vma, start, page); | |
505 | if (err < 0) | |
506 | goto out; | |
507 | start += PAGE_SIZE; | |
508 | kaddr += PAGE_SIZE; | |
509 | } | |
510 | } | |
511 | } | |
512 | ||
513 | atomic_inc(&nlk->mapped); | |
514 | vma->vm_ops = &netlink_mmap_ops; | |
515 | err = 0; | |
516 | out: | |
517 | mutex_unlock(&nlk->pg_vec_lock); | |
7cdbac71 | 518 | return err; |
ccdfcc39 | 519 | } |
9652e931 PM |
520 | |
521 | static void netlink_frame_flush_dcache(const struct nl_mmap_hdr *hdr) | |
522 | { | |
523 | #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1 | |
524 | struct page *p_start, *p_end; | |
525 | ||
526 | /* First page is flushed through netlink_{get,set}_status */ | |
527 | p_start = pgvec_to_page(hdr + PAGE_SIZE); | |
1d5085cb | 528 | p_end = pgvec_to_page((void *)hdr + NL_MMAP_HDRLEN + hdr->nm_len - 1); |
9652e931 PM |
529 | while (p_start <= p_end) { |
530 | flush_dcache_page(p_start); | |
531 | p_start++; | |
532 | } | |
533 | #endif | |
534 | } | |
535 | ||
536 | static enum nl_mmap_status netlink_get_status(const struct nl_mmap_hdr *hdr) | |
537 | { | |
538 | smp_rmb(); | |
539 | flush_dcache_page(pgvec_to_page(hdr)); | |
540 | return hdr->nm_status; | |
541 | } | |
542 | ||
543 | static void netlink_set_status(struct nl_mmap_hdr *hdr, | |
544 | enum nl_mmap_status status) | |
545 | { | |
546 | hdr->nm_status = status; | |
547 | flush_dcache_page(pgvec_to_page(hdr)); | |
548 | smp_wmb(); | |
549 | } | |
550 | ||
551 | static struct nl_mmap_hdr * | |
552 | __netlink_lookup_frame(const struct netlink_ring *ring, unsigned int pos) | |
553 | { | |
554 | unsigned int pg_vec_pos, frame_off; | |
555 | ||
556 | pg_vec_pos = pos / ring->frames_per_block; | |
557 | frame_off = pos % ring->frames_per_block; | |
558 | ||
559 | return ring->pg_vec[pg_vec_pos] + (frame_off * ring->frame_size); | |
560 | } | |
561 | ||
562 | static struct nl_mmap_hdr * | |
563 | netlink_lookup_frame(const struct netlink_ring *ring, unsigned int pos, | |
564 | enum nl_mmap_status status) | |
565 | { | |
566 | struct nl_mmap_hdr *hdr; | |
567 | ||
568 | hdr = __netlink_lookup_frame(ring, pos); | |
569 | if (netlink_get_status(hdr) != status) | |
570 | return NULL; | |
571 | ||
572 | return hdr; | |
573 | } | |
574 | ||
575 | static struct nl_mmap_hdr * | |
576 | netlink_current_frame(const struct netlink_ring *ring, | |
577 | enum nl_mmap_status status) | |
578 | { | |
579 | return netlink_lookup_frame(ring, ring->head, status); | |
580 | } | |
581 | ||
582 | static struct nl_mmap_hdr * | |
583 | netlink_previous_frame(const struct netlink_ring *ring, | |
584 | enum nl_mmap_status status) | |
585 | { | |
586 | unsigned int prev; | |
587 | ||
588 | prev = ring->head ? ring->head - 1 : ring->frame_max; | |
589 | return netlink_lookup_frame(ring, prev, status); | |
590 | } | |
591 | ||
592 | static void netlink_increment_head(struct netlink_ring *ring) | |
593 | { | |
594 | ring->head = ring->head != ring->frame_max ? ring->head + 1 : 0; | |
595 | } | |
596 | ||
597 | static void netlink_forward_ring(struct netlink_ring *ring) | |
598 | { | |
599 | unsigned int head = ring->head, pos = head; | |
600 | const struct nl_mmap_hdr *hdr; | |
601 | ||
602 | do { | |
603 | hdr = __netlink_lookup_frame(ring, pos); | |
604 | if (hdr->nm_status == NL_MMAP_STATUS_UNUSED) | |
605 | break; | |
606 | if (hdr->nm_status != NL_MMAP_STATUS_SKIP) | |
607 | break; | |
608 | netlink_increment_head(ring); | |
609 | } while (ring->head != head); | |
610 | } | |
611 | ||
cd1df525 PM |
612 | static bool netlink_dump_space(struct netlink_sock *nlk) |
613 | { | |
614 | struct netlink_ring *ring = &nlk->rx_ring; | |
615 | struct nl_mmap_hdr *hdr; | |
616 | unsigned int n; | |
617 | ||
618 | hdr = netlink_current_frame(ring, NL_MMAP_STATUS_UNUSED); | |
619 | if (hdr == NULL) | |
620 | return false; | |
621 | ||
622 | n = ring->head + ring->frame_max / 2; | |
623 | if (n > ring->frame_max) | |
624 | n -= ring->frame_max; | |
625 | ||
626 | hdr = __netlink_lookup_frame(ring, n); | |
627 | ||
628 | return hdr->nm_status == NL_MMAP_STATUS_UNUSED; | |
629 | } | |
630 | ||
9652e931 PM |
631 | static unsigned int netlink_poll(struct file *file, struct socket *sock, |
632 | poll_table *wait) | |
633 | { | |
634 | struct sock *sk = sock->sk; | |
635 | struct netlink_sock *nlk = nlk_sk(sk); | |
636 | unsigned int mask; | |
cd1df525 | 637 | int err; |
9652e931 | 638 | |
cd1df525 PM |
639 | if (nlk->rx_ring.pg_vec != NULL) { |
640 | /* Memory mapped sockets don't call recvmsg(), so flow control | |
641 | * for dumps is performed here. A dump is allowed to continue | |
642 | * if at least half the ring is unused. | |
643 | */ | |
16b304f3 | 644 | while (nlk->cb_running && netlink_dump_space(nlk)) { |
cd1df525 PM |
645 | err = netlink_dump(sk); |
646 | if (err < 0) { | |
ac30ef83 | 647 | sk->sk_err = -err; |
cd1df525 PM |
648 | sk->sk_error_report(sk); |
649 | break; | |
650 | } | |
651 | } | |
652 | netlink_rcv_wake(sk); | |
653 | } | |
5fd96123 | 654 | |
9652e931 PM |
655 | mask = datagram_poll(file, sock, wait); |
656 | ||
657 | spin_lock_bh(&sk->sk_receive_queue.lock); | |
658 | if (nlk->rx_ring.pg_vec) { | |
659 | netlink_forward_ring(&nlk->rx_ring); | |
660 | if (!netlink_previous_frame(&nlk->rx_ring, NL_MMAP_STATUS_UNUSED)) | |
661 | mask |= POLLIN | POLLRDNORM; | |
662 | } | |
663 | spin_unlock_bh(&sk->sk_receive_queue.lock); | |
664 | ||
665 | spin_lock_bh(&sk->sk_write_queue.lock); | |
666 | if (nlk->tx_ring.pg_vec) { | |
667 | if (netlink_current_frame(&nlk->tx_ring, NL_MMAP_STATUS_UNUSED)) | |
668 | mask |= POLLOUT | POLLWRNORM; | |
669 | } | |
670 | spin_unlock_bh(&sk->sk_write_queue.lock); | |
671 | ||
672 | return mask; | |
673 | } | |
674 | ||
675 | static struct nl_mmap_hdr *netlink_mmap_hdr(struct sk_buff *skb) | |
676 | { | |
677 | return (struct nl_mmap_hdr *)(skb->head - NL_MMAP_HDRLEN); | |
678 | } | |
679 | ||
680 | static void netlink_ring_setup_skb(struct sk_buff *skb, struct sock *sk, | |
681 | struct netlink_ring *ring, | |
682 | struct nl_mmap_hdr *hdr) | |
683 | { | |
684 | unsigned int size; | |
685 | void *data; | |
686 | ||
687 | size = ring->frame_size - NL_MMAP_HDRLEN; | |
688 | data = (void *)hdr + NL_MMAP_HDRLEN; | |
689 | ||
690 | skb->head = data; | |
691 | skb->data = data; | |
692 | skb_reset_tail_pointer(skb); | |
693 | skb->end = skb->tail + size; | |
694 | skb->len = 0; | |
695 | ||
696 | skb->destructor = netlink_skb_destructor; | |
697 | NETLINK_CB(skb).flags |= NETLINK_SKB_MMAPED; | |
698 | NETLINK_CB(skb).sk = sk; | |
699 | } | |
5fd96123 PM |
700 | |
701 | static int netlink_mmap_sendmsg(struct sock *sk, struct msghdr *msg, | |
702 | u32 dst_portid, u32 dst_group, | |
703 | struct sock_iocb *siocb) | |
704 | { | |
705 | struct netlink_sock *nlk = nlk_sk(sk); | |
706 | struct netlink_ring *ring; | |
707 | struct nl_mmap_hdr *hdr; | |
708 | struct sk_buff *skb; | |
709 | unsigned int maxlen; | |
710 | bool excl = true; | |
711 | int err = 0, len = 0; | |
712 | ||
713 | /* Netlink messages are validated by the receiver before processing. | |
714 | * In order to avoid userspace changing the contents of the message | |
715 | * after validation, the socket and the ring may only be used by a | |
716 | * single process, otherwise we fall back to copying. | |
717 | */ | |
24dff96a | 718 | if (atomic_long_read(&sk->sk_socket->file->f_count) > 1 || |
5fd96123 PM |
719 | atomic_read(&nlk->mapped) > 1) |
720 | excl = false; | |
721 | ||
722 | mutex_lock(&nlk->pg_vec_lock); | |
723 | ||
724 | ring = &nlk->tx_ring; | |
725 | maxlen = ring->frame_size - NL_MMAP_HDRLEN; | |
726 | ||
727 | do { | |
728 | hdr = netlink_current_frame(ring, NL_MMAP_STATUS_VALID); | |
729 | if (hdr == NULL) { | |
730 | if (!(msg->msg_flags & MSG_DONTWAIT) && | |
731 | atomic_read(&nlk->tx_ring.pending)) | |
732 | schedule(); | |
733 | continue; | |
734 | } | |
735 | if (hdr->nm_len > maxlen) { | |
736 | err = -EINVAL; | |
737 | goto out; | |
738 | } | |
739 | ||
740 | netlink_frame_flush_dcache(hdr); | |
741 | ||
742 | if (likely(dst_portid == 0 && dst_group == 0 && excl)) { | |
743 | skb = alloc_skb_head(GFP_KERNEL); | |
744 | if (skb == NULL) { | |
745 | err = -ENOBUFS; | |
746 | goto out; | |
747 | } | |
748 | sock_hold(sk); | |
749 | netlink_ring_setup_skb(skb, sk, ring, hdr); | |
750 | NETLINK_CB(skb).flags |= NETLINK_SKB_TX; | |
751 | __skb_put(skb, hdr->nm_len); | |
752 | netlink_set_status(hdr, NL_MMAP_STATUS_RESERVED); | |
753 | atomic_inc(&ring->pending); | |
754 | } else { | |
755 | skb = alloc_skb(hdr->nm_len, GFP_KERNEL); | |
756 | if (skb == NULL) { | |
757 | err = -ENOBUFS; | |
758 | goto out; | |
759 | } | |
760 | __skb_put(skb, hdr->nm_len); | |
761 | memcpy(skb->data, (void *)hdr + NL_MMAP_HDRLEN, hdr->nm_len); | |
762 | netlink_set_status(hdr, NL_MMAP_STATUS_UNUSED); | |
763 | } | |
764 | ||
765 | netlink_increment_head(ring); | |
766 | ||
767 | NETLINK_CB(skb).portid = nlk->portid; | |
768 | NETLINK_CB(skb).dst_group = dst_group; | |
769 | NETLINK_CB(skb).creds = siocb->scm->creds; | |
770 | ||
771 | err = security_netlink_send(sk, skb); | |
772 | if (err) { | |
773 | kfree_skb(skb); | |
774 | goto out; | |
775 | } | |
776 | ||
777 | if (unlikely(dst_group)) { | |
778 | atomic_inc(&skb->users); | |
779 | netlink_broadcast(sk, skb, dst_portid, dst_group, | |
780 | GFP_KERNEL); | |
781 | } | |
782 | err = netlink_unicast(sk, skb, dst_portid, | |
783 | msg->msg_flags & MSG_DONTWAIT); | |
784 | if (err < 0) | |
785 | goto out; | |
786 | len += err; | |
787 | ||
788 | } while (hdr != NULL || | |
789 | (!(msg->msg_flags & MSG_DONTWAIT) && | |
790 | atomic_read(&nlk->tx_ring.pending))); | |
791 | ||
792 | if (len > 0) | |
793 | err = len; | |
794 | out: | |
795 | mutex_unlock(&nlk->pg_vec_lock); | |
796 | return err; | |
797 | } | |
f9c22888 PM |
798 | |
799 | static void netlink_queue_mmaped_skb(struct sock *sk, struct sk_buff *skb) | |
800 | { | |
801 | struct nl_mmap_hdr *hdr; | |
802 | ||
803 | hdr = netlink_mmap_hdr(skb); | |
804 | hdr->nm_len = skb->len; | |
805 | hdr->nm_group = NETLINK_CB(skb).dst_group; | |
806 | hdr->nm_pid = NETLINK_CB(skb).creds.pid; | |
1bf9310a ND |
807 | hdr->nm_uid = from_kuid(sk_user_ns(sk), NETLINK_CB(skb).creds.uid); |
808 | hdr->nm_gid = from_kgid(sk_user_ns(sk), NETLINK_CB(skb).creds.gid); | |
f9c22888 PM |
809 | netlink_frame_flush_dcache(hdr); |
810 | netlink_set_status(hdr, NL_MMAP_STATUS_VALID); | |
811 | ||
812 | NETLINK_CB(skb).flags |= NETLINK_SKB_DELIVERED; | |
813 | kfree_skb(skb); | |
814 | } | |
815 | ||
816 | static void netlink_ring_set_copied(struct sock *sk, struct sk_buff *skb) | |
817 | { | |
818 | struct netlink_sock *nlk = nlk_sk(sk); | |
819 | struct netlink_ring *ring = &nlk->rx_ring; | |
820 | struct nl_mmap_hdr *hdr; | |
821 | ||
822 | spin_lock_bh(&sk->sk_receive_queue.lock); | |
823 | hdr = netlink_current_frame(ring, NL_MMAP_STATUS_UNUSED); | |
824 | if (hdr == NULL) { | |
825 | spin_unlock_bh(&sk->sk_receive_queue.lock); | |
826 | kfree_skb(skb); | |
cd1df525 | 827 | netlink_overrun(sk); |
f9c22888 PM |
828 | return; |
829 | } | |
830 | netlink_increment_head(ring); | |
831 | __skb_queue_tail(&sk->sk_receive_queue, skb); | |
832 | spin_unlock_bh(&sk->sk_receive_queue.lock); | |
833 | ||
834 | hdr->nm_len = skb->len; | |
835 | hdr->nm_group = NETLINK_CB(skb).dst_group; | |
836 | hdr->nm_pid = NETLINK_CB(skb).creds.pid; | |
1bf9310a ND |
837 | hdr->nm_uid = from_kuid(sk_user_ns(sk), NETLINK_CB(skb).creds.uid); |
838 | hdr->nm_gid = from_kgid(sk_user_ns(sk), NETLINK_CB(skb).creds.gid); | |
f9c22888 PM |
839 | netlink_set_status(hdr, NL_MMAP_STATUS_COPY); |
840 | } | |
841 | ||
ccdfcc39 | 842 | #else /* CONFIG_NETLINK_MMAP */ |
9652e931 | 843 | #define netlink_skb_is_mmaped(skb) false |
f9c22888 | 844 | #define netlink_rx_is_mmaped(sk) false |
5fd96123 | 845 | #define netlink_tx_is_mmaped(sk) false |
ccdfcc39 | 846 | #define netlink_mmap sock_no_mmap |
9652e931 | 847 | #define netlink_poll datagram_poll |
5fd96123 | 848 | #define netlink_mmap_sendmsg(sk, msg, dst_portid, dst_group, siocb) 0 |
ccdfcc39 PM |
849 | #endif /* CONFIG_NETLINK_MMAP */ |
850 | ||
cf0a018a PM |
851 | static void netlink_skb_destructor(struct sk_buff *skb) |
852 | { | |
9652e931 PM |
853 | #ifdef CONFIG_NETLINK_MMAP |
854 | struct nl_mmap_hdr *hdr; | |
855 | struct netlink_ring *ring; | |
856 | struct sock *sk; | |
857 | ||
858 | /* If a packet from the kernel to userspace was freed because of an | |
859 | * error without being delivered to userspace, the kernel must reset | |
860 | * the status. In the direction userspace to kernel, the status is | |
861 | * always reset here after the packet was processed and freed. | |
862 | */ | |
863 | if (netlink_skb_is_mmaped(skb)) { | |
864 | hdr = netlink_mmap_hdr(skb); | |
865 | sk = NETLINK_CB(skb).sk; | |
866 | ||
5fd96123 PM |
867 | if (NETLINK_CB(skb).flags & NETLINK_SKB_TX) { |
868 | netlink_set_status(hdr, NL_MMAP_STATUS_UNUSED); | |
869 | ring = &nlk_sk(sk)->tx_ring; | |
870 | } else { | |
871 | if (!(NETLINK_CB(skb).flags & NETLINK_SKB_DELIVERED)) { | |
872 | hdr->nm_len = 0; | |
873 | netlink_set_status(hdr, NL_MMAP_STATUS_VALID); | |
874 | } | |
875 | ring = &nlk_sk(sk)->rx_ring; | |
9652e931 | 876 | } |
9652e931 PM |
877 | |
878 | WARN_ON(atomic_read(&ring->pending) == 0); | |
879 | atomic_dec(&ring->pending); | |
880 | sock_put(sk); | |
881 | ||
5e71d9d7 | 882 | skb->head = NULL; |
9652e931 PM |
883 | } |
884 | #endif | |
c05cdb1b | 885 | if (is_vmalloc_addr(skb->head)) { |
3a36515f PN |
886 | if (!skb->cloned || |
887 | !atomic_dec_return(&(skb_shinfo(skb)->dataref))) | |
888 | vfree(skb->head); | |
889 | ||
c05cdb1b PNA |
890 | skb->head = NULL; |
891 | } | |
9652e931 PM |
892 | if (skb->sk != NULL) |
893 | sock_rfree(skb); | |
cf0a018a PM |
894 | } |
895 | ||
896 | static void netlink_skb_set_owner_r(struct sk_buff *skb, struct sock *sk) | |
897 | { | |
898 | WARN_ON(skb->sk != NULL); | |
899 | skb->sk = sk; | |
900 | skb->destructor = netlink_skb_destructor; | |
901 | atomic_add(skb->truesize, &sk->sk_rmem_alloc); | |
902 | sk_mem_charge(sk, skb->truesize); | |
903 | } | |
904 | ||
1da177e4 LT |
905 | static void netlink_sock_destruct(struct sock *sk) |
906 | { | |
3f660d66 HX |
907 | struct netlink_sock *nlk = nlk_sk(sk); |
908 | ||
16b304f3 PS |
909 | if (nlk->cb_running) { |
910 | if (nlk->cb.done) | |
911 | nlk->cb.done(&nlk->cb); | |
6dc878a8 | 912 | |
16b304f3 PS |
913 | module_put(nlk->cb.module); |
914 | kfree_skb(nlk->cb.skb); | |
3f660d66 HX |
915 | } |
916 | ||
1da177e4 | 917 | skb_queue_purge(&sk->sk_receive_queue); |
ccdfcc39 PM |
918 | #ifdef CONFIG_NETLINK_MMAP |
919 | if (1) { | |
920 | struct nl_mmap_req req; | |
921 | ||
922 | memset(&req, 0, sizeof(req)); | |
923 | if (nlk->rx_ring.pg_vec) | |
924 | netlink_set_ring(sk, &req, true, false); | |
925 | memset(&req, 0, sizeof(req)); | |
926 | if (nlk->tx_ring.pg_vec) | |
927 | netlink_set_ring(sk, &req, true, true); | |
928 | } | |
929 | #endif /* CONFIG_NETLINK_MMAP */ | |
1da177e4 LT |
930 | |
931 | if (!sock_flag(sk, SOCK_DEAD)) { | |
6ac552fd | 932 | printk(KERN_ERR "Freeing alive netlink socket %p\n", sk); |
1da177e4 LT |
933 | return; |
934 | } | |
547b792c IJ |
935 | |
936 | WARN_ON(atomic_read(&sk->sk_rmem_alloc)); | |
937 | WARN_ON(atomic_read(&sk->sk_wmem_alloc)); | |
938 | WARN_ON(nlk_sk(sk)->groups); | |
1da177e4 LT |
939 | } |
940 | ||
6ac552fd PM |
941 | /* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on |
942 | * SMP. Look, when several writers sleep and reader wakes them up, all but one | |
1da177e4 LT |
943 | * immediately hit write lock and grab all the cpus. Exclusive sleep solves |
944 | * this, _but_ remember, it adds useless work on UP machines. | |
945 | */ | |
946 | ||
d136f1bd | 947 | void netlink_table_grab(void) |
9a429c49 | 948 | __acquires(nl_table_lock) |
1da177e4 | 949 | { |
d136f1bd JB |
950 | might_sleep(); |
951 | ||
6abd219c | 952 | write_lock_irq(&nl_table_lock); |
1da177e4 LT |
953 | |
954 | if (atomic_read(&nl_table_users)) { | |
955 | DECLARE_WAITQUEUE(wait, current); | |
956 | ||
957 | add_wait_queue_exclusive(&nl_table_wait, &wait); | |
6ac552fd | 958 | for (;;) { |
1da177e4 LT |
959 | set_current_state(TASK_UNINTERRUPTIBLE); |
960 | if (atomic_read(&nl_table_users) == 0) | |
961 | break; | |
6abd219c | 962 | write_unlock_irq(&nl_table_lock); |
1da177e4 | 963 | schedule(); |
6abd219c | 964 | write_lock_irq(&nl_table_lock); |
1da177e4 LT |
965 | } |
966 | ||
967 | __set_current_state(TASK_RUNNING); | |
968 | remove_wait_queue(&nl_table_wait, &wait); | |
969 | } | |
970 | } | |
971 | ||
d136f1bd | 972 | void netlink_table_ungrab(void) |
9a429c49 | 973 | __releases(nl_table_lock) |
1da177e4 | 974 | { |
6abd219c | 975 | write_unlock_irq(&nl_table_lock); |
1da177e4 LT |
976 | wake_up(&nl_table_wait); |
977 | } | |
978 | ||
6ac552fd | 979 | static inline void |
1da177e4 LT |
980 | netlink_lock_table(void) |
981 | { | |
982 | /* read_lock() synchronizes us to netlink_table_grab */ | |
983 | ||
984 | read_lock(&nl_table_lock); | |
985 | atomic_inc(&nl_table_users); | |
986 | read_unlock(&nl_table_lock); | |
987 | } | |
988 | ||
6ac552fd | 989 | static inline void |
1da177e4 LT |
990 | netlink_unlock_table(void) |
991 | { | |
992 | if (atomic_dec_and_test(&nl_table_users)) | |
993 | wake_up(&nl_table_wait); | |
994 | } | |
995 | ||
e341694e | 996 | struct netlink_compare_arg |
1da177e4 | 997 | { |
e341694e TG |
998 | struct net *net; |
999 | u32 portid; | |
1000 | }; | |
1da177e4 | 1001 | |
e341694e | 1002 | static bool netlink_compare(void *ptr, void *arg) |
1da177e4 | 1003 | { |
e341694e TG |
1004 | struct netlink_compare_arg *x = arg; |
1005 | struct sock *sk = ptr; | |
1da177e4 | 1006 | |
e341694e TG |
1007 | return nlk_sk(sk)->portid == x->portid && |
1008 | net_eq(sock_net(sk), x->net); | |
1da177e4 LT |
1009 | } |
1010 | ||
e341694e TG |
1011 | static struct sock *__netlink_lookup(struct netlink_table *table, u32 portid, |
1012 | struct net *net) | |
1da177e4 | 1013 | { |
e341694e TG |
1014 | struct netlink_compare_arg arg = { |
1015 | .net = net, | |
1016 | .portid = portid, | |
1017 | }; | |
1018 | u32 hash; | |
1da177e4 | 1019 | |
e341694e | 1020 | hash = rhashtable_hashfn(&table->hash, &portid, sizeof(portid)); |
1da177e4 | 1021 | |
e341694e TG |
1022 | return rhashtable_lookup_compare(&table->hash, hash, |
1023 | &netlink_compare, &arg); | |
1da177e4 LT |
1024 | } |
1025 | ||
e341694e | 1026 | static struct sock *netlink_lookup(struct net *net, int protocol, u32 portid) |
1da177e4 | 1027 | { |
e341694e TG |
1028 | struct netlink_table *table = &nl_table[protocol]; |
1029 | struct sock *sk; | |
1da177e4 | 1030 | |
e341694e TG |
1031 | rcu_read_lock(); |
1032 | sk = __netlink_lookup(table, portid, net); | |
1033 | if (sk) | |
1034 | sock_hold(sk); | |
1035 | rcu_read_unlock(); | |
1da177e4 | 1036 | |
e341694e | 1037 | return sk; |
1da177e4 LT |
1038 | } |
1039 | ||
90ddc4f0 | 1040 | static const struct proto_ops netlink_ops; |
1da177e4 | 1041 | |
4277a083 PM |
1042 | static void |
1043 | netlink_update_listeners(struct sock *sk) | |
1044 | { | |
1045 | struct netlink_table *tbl = &nl_table[sk->sk_protocol]; | |
4277a083 PM |
1046 | unsigned long mask; |
1047 | unsigned int i; | |
6d772ac5 ED |
1048 | struct listeners *listeners; |
1049 | ||
1050 | listeners = nl_deref_protected(tbl->listeners); | |
1051 | if (!listeners) | |
1052 | return; | |
4277a083 | 1053 | |
b4ff4f04 | 1054 | for (i = 0; i < NLGRPLONGS(tbl->groups); i++) { |
4277a083 | 1055 | mask = 0; |
b67bfe0d | 1056 | sk_for_each_bound(sk, &tbl->mc_list) { |
b4ff4f04 JB |
1057 | if (i < NLGRPLONGS(nlk_sk(sk)->ngroups)) |
1058 | mask |= nlk_sk(sk)->groups[i]; | |
1059 | } | |
6d772ac5 | 1060 | listeners->masks[i] = mask; |
4277a083 PM |
1061 | } |
1062 | /* this function is only called with the netlink table "grabbed", which | |
1063 | * makes sure updates are visible before bind or setsockopt return. */ | |
1064 | } | |
1065 | ||
15e47304 | 1066 | static int netlink_insert(struct sock *sk, struct net *net, u32 portid) |
1da177e4 | 1067 | { |
da12c90e | 1068 | struct netlink_table *table = &nl_table[sk->sk_protocol]; |
1da177e4 | 1069 | int err = -EADDRINUSE; |
1da177e4 | 1070 | |
e341694e TG |
1071 | mutex_lock(&nl_sk_hash_lock); |
1072 | if (__netlink_lookup(table, portid, net)) | |
1da177e4 LT |
1073 | goto err; |
1074 | ||
1075 | err = -EBUSY; | |
15e47304 | 1076 | if (nlk_sk(sk)->portid) |
1da177e4 LT |
1077 | goto err; |
1078 | ||
1079 | err = -ENOMEM; | |
e341694e | 1080 | if (BITS_PER_LONG > 32 && unlikely(table->hash.nelems >= UINT_MAX)) |
1da177e4 LT |
1081 | goto err; |
1082 | ||
15e47304 | 1083 | nlk_sk(sk)->portid = portid; |
e341694e TG |
1084 | sock_hold(sk); |
1085 | rhashtable_insert(&table->hash, &nlk_sk(sk)->node, GFP_KERNEL); | |
1da177e4 | 1086 | err = 0; |
1da177e4 | 1087 | err: |
e341694e | 1088 | mutex_unlock(&nl_sk_hash_lock); |
1da177e4 LT |
1089 | return err; |
1090 | } | |
1091 | ||
1092 | static void netlink_remove(struct sock *sk) | |
1093 | { | |
e341694e TG |
1094 | struct netlink_table *table; |
1095 | ||
1096 | mutex_lock(&nl_sk_hash_lock); | |
1097 | table = &nl_table[sk->sk_protocol]; | |
1098 | if (rhashtable_remove(&table->hash, &nlk_sk(sk)->node, GFP_KERNEL)) { | |
1099 | WARN_ON(atomic_read(&sk->sk_refcnt) == 1); | |
1100 | __sock_put(sk); | |
1101 | } | |
1102 | mutex_unlock(&nl_sk_hash_lock); | |
1103 | ||
1da177e4 | 1104 | netlink_table_grab(); |
f7fa9b10 | 1105 | if (nlk_sk(sk)->subscriptions) |
1da177e4 LT |
1106 | __sk_del_bind_node(sk); |
1107 | netlink_table_ungrab(); | |
1108 | } | |
1109 | ||
1110 | static struct proto netlink_proto = { | |
1111 | .name = "NETLINK", | |
1112 | .owner = THIS_MODULE, | |
1113 | .obj_size = sizeof(struct netlink_sock), | |
1114 | }; | |
1115 | ||
1b8d7ae4 EB |
1116 | static int __netlink_create(struct net *net, struct socket *sock, |
1117 | struct mutex *cb_mutex, int protocol) | |
1da177e4 LT |
1118 | { |
1119 | struct sock *sk; | |
1120 | struct netlink_sock *nlk; | |
ab33a171 PM |
1121 | |
1122 | sock->ops = &netlink_ops; | |
1123 | ||
6257ff21 | 1124 | sk = sk_alloc(net, PF_NETLINK, GFP_KERNEL, &netlink_proto); |
ab33a171 PM |
1125 | if (!sk) |
1126 | return -ENOMEM; | |
1127 | ||
1128 | sock_init_data(sock, sk); | |
1129 | ||
1130 | nlk = nlk_sk(sk); | |
658cb354 | 1131 | if (cb_mutex) { |
ffa4d721 | 1132 | nlk->cb_mutex = cb_mutex; |
658cb354 | 1133 | } else { |
ffa4d721 PM |
1134 | nlk->cb_mutex = &nlk->cb_def_mutex; |
1135 | mutex_init(nlk->cb_mutex); | |
1136 | } | |
ab33a171 | 1137 | init_waitqueue_head(&nlk->wait); |
ccdfcc39 PM |
1138 | #ifdef CONFIG_NETLINK_MMAP |
1139 | mutex_init(&nlk->pg_vec_lock); | |
1140 | #endif | |
ab33a171 PM |
1141 | |
1142 | sk->sk_destruct = netlink_sock_destruct; | |
1143 | sk->sk_protocol = protocol; | |
1144 | return 0; | |
1145 | } | |
1146 | ||
3f378b68 EP |
1147 | static int netlink_create(struct net *net, struct socket *sock, int protocol, |
1148 | int kern) | |
ab33a171 PM |
1149 | { |
1150 | struct module *module = NULL; | |
af65bdfc | 1151 | struct mutex *cb_mutex; |
f7fa9b10 | 1152 | struct netlink_sock *nlk; |
4f520900 RGB |
1153 | int (*bind)(int group); |
1154 | void (*unbind)(int group); | |
ab33a171 | 1155 | int err = 0; |
1da177e4 LT |
1156 | |
1157 | sock->state = SS_UNCONNECTED; | |
1158 | ||
1159 | if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM) | |
1160 | return -ESOCKTNOSUPPORT; | |
1161 | ||
6ac552fd | 1162 | if (protocol < 0 || protocol >= MAX_LINKS) |
1da177e4 LT |
1163 | return -EPROTONOSUPPORT; |
1164 | ||
77247bbb | 1165 | netlink_lock_table(); |
95a5afca | 1166 | #ifdef CONFIG_MODULES |
ab33a171 | 1167 | if (!nl_table[protocol].registered) { |
77247bbb | 1168 | netlink_unlock_table(); |
4fdb3bb7 | 1169 | request_module("net-pf-%d-proto-%d", PF_NETLINK, protocol); |
77247bbb | 1170 | netlink_lock_table(); |
4fdb3bb7 | 1171 | } |
ab33a171 PM |
1172 | #endif |
1173 | if (nl_table[protocol].registered && | |
1174 | try_module_get(nl_table[protocol].module)) | |
1175 | module = nl_table[protocol].module; | |
974c37e9 AD |
1176 | else |
1177 | err = -EPROTONOSUPPORT; | |
af65bdfc | 1178 | cb_mutex = nl_table[protocol].cb_mutex; |
03292745 | 1179 | bind = nl_table[protocol].bind; |
4f520900 | 1180 | unbind = nl_table[protocol].unbind; |
77247bbb | 1181 | netlink_unlock_table(); |
4fdb3bb7 | 1182 | |
974c37e9 AD |
1183 | if (err < 0) |
1184 | goto out; | |
1185 | ||
6ac552fd PM |
1186 | err = __netlink_create(net, sock, cb_mutex, protocol); |
1187 | if (err < 0) | |
f7fa9b10 PM |
1188 | goto out_module; |
1189 | ||
6f756a8c | 1190 | local_bh_disable(); |
c1fd3b94 | 1191 | sock_prot_inuse_add(net, &netlink_proto, 1); |
6f756a8c DM |
1192 | local_bh_enable(); |
1193 | ||
f7fa9b10 | 1194 | nlk = nlk_sk(sock->sk); |
f7fa9b10 | 1195 | nlk->module = module; |
03292745 | 1196 | nlk->netlink_bind = bind; |
4f520900 | 1197 | nlk->netlink_unbind = unbind; |
ab33a171 PM |
1198 | out: |
1199 | return err; | |
1da177e4 | 1200 | |
ab33a171 PM |
1201 | out_module: |
1202 | module_put(module); | |
1203 | goto out; | |
1da177e4 LT |
1204 | } |
1205 | ||
1206 | static int netlink_release(struct socket *sock) | |
1207 | { | |
1208 | struct sock *sk = sock->sk; | |
1209 | struct netlink_sock *nlk; | |
1210 | ||
1211 | if (!sk) | |
1212 | return 0; | |
1213 | ||
1214 | netlink_remove(sk); | |
ac57b3a9 | 1215 | sock_orphan(sk); |
1da177e4 LT |
1216 | nlk = nlk_sk(sk); |
1217 | ||
3f660d66 HX |
1218 | /* |
1219 | * OK. Socket is unlinked, any packets that arrive now | |
1220 | * will be purged. | |
1221 | */ | |
1da177e4 | 1222 | |
1da177e4 LT |
1223 | sock->sk = NULL; |
1224 | wake_up_interruptible_all(&nlk->wait); | |
1225 | ||
1226 | skb_queue_purge(&sk->sk_write_queue); | |
1227 | ||
15e47304 | 1228 | if (nlk->portid) { |
1da177e4 | 1229 | struct netlink_notify n = { |
3b1e0a65 | 1230 | .net = sock_net(sk), |
1da177e4 | 1231 | .protocol = sk->sk_protocol, |
15e47304 | 1232 | .portid = nlk->portid, |
1da177e4 | 1233 | }; |
e041c683 AS |
1234 | atomic_notifier_call_chain(&netlink_chain, |
1235 | NETLINK_URELEASE, &n); | |
746fac4d | 1236 | } |
4fdb3bb7 | 1237 | |
5e7c001c | 1238 | module_put(nlk->module); |
4fdb3bb7 | 1239 | |
4277a083 | 1240 | netlink_table_grab(); |
aed81560 | 1241 | if (netlink_is_kernel(sk)) { |
869e58f8 DL |
1242 | BUG_ON(nl_table[sk->sk_protocol].registered == 0); |
1243 | if (--nl_table[sk->sk_protocol].registered == 0) { | |
6d772ac5 ED |
1244 | struct listeners *old; |
1245 | ||
1246 | old = nl_deref_protected(nl_table[sk->sk_protocol].listeners); | |
1247 | RCU_INIT_POINTER(nl_table[sk->sk_protocol].listeners, NULL); | |
1248 | kfree_rcu(old, rcu); | |
869e58f8 | 1249 | nl_table[sk->sk_protocol].module = NULL; |
9785e10a | 1250 | nl_table[sk->sk_protocol].bind = NULL; |
4f520900 | 1251 | nl_table[sk->sk_protocol].unbind = NULL; |
9785e10a | 1252 | nl_table[sk->sk_protocol].flags = 0; |
869e58f8 DL |
1253 | nl_table[sk->sk_protocol].registered = 0; |
1254 | } | |
658cb354 | 1255 | } else if (nlk->subscriptions) { |
4277a083 | 1256 | netlink_update_listeners(sk); |
658cb354 | 1257 | } |
4277a083 | 1258 | netlink_table_ungrab(); |
77247bbb | 1259 | |
e341694e TG |
1260 | /* Wait for readers to complete */ |
1261 | synchronize_net(); | |
1262 | ||
f7fa9b10 PM |
1263 | kfree(nlk->groups); |
1264 | nlk->groups = NULL; | |
1265 | ||
3755810c | 1266 | local_bh_disable(); |
c1fd3b94 | 1267 | sock_prot_inuse_add(sock_net(sk), &netlink_proto, -1); |
3755810c | 1268 | local_bh_enable(); |
1da177e4 LT |
1269 | sock_put(sk); |
1270 | return 0; | |
1271 | } | |
1272 | ||
1273 | static int netlink_autobind(struct socket *sock) | |
1274 | { | |
1275 | struct sock *sk = sock->sk; | |
3b1e0a65 | 1276 | struct net *net = sock_net(sk); |
da12c90e | 1277 | struct netlink_table *table = &nl_table[sk->sk_protocol]; |
15e47304 | 1278 | s32 portid = task_tgid_vnr(current); |
1da177e4 LT |
1279 | int err; |
1280 | static s32 rover = -4097; | |
1281 | ||
1282 | retry: | |
1283 | cond_resched(); | |
e341694e TG |
1284 | rcu_read_lock(); |
1285 | if (__netlink_lookup(table, portid, net)) { | |
1286 | /* Bind collision, search negative portid values. */ | |
1287 | portid = rover--; | |
1288 | if (rover > -4097) | |
1289 | rover = -4097; | |
1290 | rcu_read_unlock(); | |
1291 | goto retry; | |
1da177e4 | 1292 | } |
e341694e | 1293 | rcu_read_unlock(); |
1da177e4 | 1294 | |
15e47304 | 1295 | err = netlink_insert(sk, net, portid); |
1da177e4 LT |
1296 | if (err == -EADDRINUSE) |
1297 | goto retry; | |
d470e3b4 DM |
1298 | |
1299 | /* If 2 threads race to autobind, that is fine. */ | |
1300 | if (err == -EBUSY) | |
1301 | err = 0; | |
1302 | ||
1303 | return err; | |
1da177e4 LT |
1304 | } |
1305 | ||
aa4cf945 EB |
1306 | /** |
1307 | * __netlink_ns_capable - General netlink message capability test | |
1308 | * @nsp: NETLINK_CB of the socket buffer holding a netlink command from userspace. | |
1309 | * @user_ns: The user namespace of the capability to use | |
1310 | * @cap: The capability to use | |
1311 | * | |
1312 | * Test to see if the opener of the socket we received the message | |
1313 | * from had when the netlink socket was created and the sender of the | |
1314 | * message has has the capability @cap in the user namespace @user_ns. | |
1315 | */ | |
1316 | bool __netlink_ns_capable(const struct netlink_skb_parms *nsp, | |
1317 | struct user_namespace *user_ns, int cap) | |
1318 | { | |
2d7a85f4 EB |
1319 | return ((nsp->flags & NETLINK_SKB_DST) || |
1320 | file_ns_capable(nsp->sk->sk_socket->file, user_ns, cap)) && | |
1321 | ns_capable(user_ns, cap); | |
aa4cf945 EB |
1322 | } |
1323 | EXPORT_SYMBOL(__netlink_ns_capable); | |
1324 | ||
1325 | /** | |
1326 | * netlink_ns_capable - General netlink message capability test | |
1327 | * @skb: socket buffer holding a netlink command from userspace | |
1328 | * @user_ns: The user namespace of the capability to use | |
1329 | * @cap: The capability to use | |
1330 | * | |
1331 | * Test to see if the opener of the socket we received the message | |
1332 | * from had when the netlink socket was created and the sender of the | |
1333 | * message has has the capability @cap in the user namespace @user_ns. | |
1334 | */ | |
1335 | bool netlink_ns_capable(const struct sk_buff *skb, | |
1336 | struct user_namespace *user_ns, int cap) | |
1337 | { | |
1338 | return __netlink_ns_capable(&NETLINK_CB(skb), user_ns, cap); | |
1339 | } | |
1340 | EXPORT_SYMBOL(netlink_ns_capable); | |
1341 | ||
1342 | /** | |
1343 | * netlink_capable - Netlink global message capability test | |
1344 | * @skb: socket buffer holding a netlink command from userspace | |
1345 | * @cap: The capability to use | |
1346 | * | |
1347 | * Test to see if the opener of the socket we received the message | |
1348 | * from had when the netlink socket was created and the sender of the | |
1349 | * message has has the capability @cap in all user namespaces. | |
1350 | */ | |
1351 | bool netlink_capable(const struct sk_buff *skb, int cap) | |
1352 | { | |
1353 | return netlink_ns_capable(skb, &init_user_ns, cap); | |
1354 | } | |
1355 | EXPORT_SYMBOL(netlink_capable); | |
1356 | ||
1357 | /** | |
1358 | * netlink_net_capable - Netlink network namespace message capability test | |
1359 | * @skb: socket buffer holding a netlink command from userspace | |
1360 | * @cap: The capability to use | |
1361 | * | |
1362 | * Test to see if the opener of the socket we received the message | |
1363 | * from had when the netlink socket was created and the sender of the | |
1364 | * message has has the capability @cap over the network namespace of | |
1365 | * the socket we received the message from. | |
1366 | */ | |
1367 | bool netlink_net_capable(const struct sk_buff *skb, int cap) | |
1368 | { | |
1369 | return netlink_ns_capable(skb, sock_net(skb->sk)->user_ns, cap); | |
1370 | } | |
1371 | EXPORT_SYMBOL(netlink_net_capable); | |
1372 | ||
5187cd05 | 1373 | static inline int netlink_allowed(const struct socket *sock, unsigned int flag) |
746fac4d | 1374 | { |
9785e10a | 1375 | return (nl_table[sock->sk->sk_protocol].flags & flag) || |
df008c91 | 1376 | ns_capable(sock_net(sock->sk)->user_ns, CAP_NET_ADMIN); |
746fac4d | 1377 | } |
1da177e4 | 1378 | |
f7fa9b10 PM |
1379 | static void |
1380 | netlink_update_subscriptions(struct sock *sk, unsigned int subscriptions) | |
1381 | { | |
1382 | struct netlink_sock *nlk = nlk_sk(sk); | |
1383 | ||
1384 | if (nlk->subscriptions && !subscriptions) | |
1385 | __sk_del_bind_node(sk); | |
1386 | else if (!nlk->subscriptions && subscriptions) | |
1387 | sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list); | |
1388 | nlk->subscriptions = subscriptions; | |
1389 | } | |
1390 | ||
b4ff4f04 | 1391 | static int netlink_realloc_groups(struct sock *sk) |
513c2500 PM |
1392 | { |
1393 | struct netlink_sock *nlk = nlk_sk(sk); | |
1394 | unsigned int groups; | |
b4ff4f04 | 1395 | unsigned long *new_groups; |
513c2500 PM |
1396 | int err = 0; |
1397 | ||
b4ff4f04 JB |
1398 | netlink_table_grab(); |
1399 | ||
513c2500 | 1400 | groups = nl_table[sk->sk_protocol].groups; |
b4ff4f04 | 1401 | if (!nl_table[sk->sk_protocol].registered) { |
513c2500 | 1402 | err = -ENOENT; |
b4ff4f04 JB |
1403 | goto out_unlock; |
1404 | } | |
513c2500 | 1405 | |
b4ff4f04 JB |
1406 | if (nlk->ngroups >= groups) |
1407 | goto out_unlock; | |
513c2500 | 1408 | |
b4ff4f04 JB |
1409 | new_groups = krealloc(nlk->groups, NLGRPSZ(groups), GFP_ATOMIC); |
1410 | if (new_groups == NULL) { | |
1411 | err = -ENOMEM; | |
1412 | goto out_unlock; | |
1413 | } | |
6ac552fd | 1414 | memset((char *)new_groups + NLGRPSZ(nlk->ngroups), 0, |
b4ff4f04 JB |
1415 | NLGRPSZ(groups) - NLGRPSZ(nlk->ngroups)); |
1416 | ||
1417 | nlk->groups = new_groups; | |
513c2500 | 1418 | nlk->ngroups = groups; |
b4ff4f04 JB |
1419 | out_unlock: |
1420 | netlink_table_ungrab(); | |
1421 | return err; | |
513c2500 PM |
1422 | } |
1423 | ||
4f520900 RGB |
1424 | static void netlink_unbind(int group, long unsigned int groups, |
1425 | struct netlink_sock *nlk) | |
1426 | { | |
1427 | int undo; | |
1428 | ||
1429 | if (!nlk->netlink_unbind) | |
1430 | return; | |
1431 | ||
1432 | for (undo = 0; undo < group; undo++) | |
1433 | if (test_bit(group, &groups)) | |
1434 | nlk->netlink_unbind(undo); | |
1435 | } | |
1436 | ||
6ac552fd PM |
1437 | static int netlink_bind(struct socket *sock, struct sockaddr *addr, |
1438 | int addr_len) | |
1da177e4 LT |
1439 | { |
1440 | struct sock *sk = sock->sk; | |
3b1e0a65 | 1441 | struct net *net = sock_net(sk); |
1da177e4 LT |
1442 | struct netlink_sock *nlk = nlk_sk(sk); |
1443 | struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; | |
1444 | int err; | |
4f520900 | 1445 | long unsigned int groups = nladdr->nl_groups; |
746fac4d | 1446 | |
4e4b5376 HFS |
1447 | if (addr_len < sizeof(struct sockaddr_nl)) |
1448 | return -EINVAL; | |
1449 | ||
1da177e4 LT |
1450 | if (nladdr->nl_family != AF_NETLINK) |
1451 | return -EINVAL; | |
1452 | ||
1453 | /* Only superuser is allowed to listen multicasts */ | |
4f520900 | 1454 | if (groups) { |
5187cd05 | 1455 | if (!netlink_allowed(sock, NL_CFG_F_NONROOT_RECV)) |
513c2500 | 1456 | return -EPERM; |
b4ff4f04 JB |
1457 | err = netlink_realloc_groups(sk); |
1458 | if (err) | |
1459 | return err; | |
513c2500 | 1460 | } |
1da177e4 | 1461 | |
4f520900 | 1462 | if (nlk->portid) |
15e47304 | 1463 | if (nladdr->nl_pid != nlk->portid) |
1da177e4 | 1464 | return -EINVAL; |
4f520900 RGB |
1465 | |
1466 | if (nlk->netlink_bind && groups) { | |
1467 | int group; | |
1468 | ||
1469 | for (group = 0; group < nlk->ngroups; group++) { | |
1470 | if (!test_bit(group, &groups)) | |
1471 | continue; | |
1472 | err = nlk->netlink_bind(group); | |
1473 | if (!err) | |
1474 | continue; | |
1475 | netlink_unbind(group, groups, nlk); | |
1476 | return err; | |
1477 | } | |
1478 | } | |
1479 | ||
1480 | if (!nlk->portid) { | |
1da177e4 | 1481 | err = nladdr->nl_pid ? |
b4b51029 | 1482 | netlink_insert(sk, net, nladdr->nl_pid) : |
1da177e4 | 1483 | netlink_autobind(sock); |
4f520900 RGB |
1484 | if (err) { |
1485 | netlink_unbind(nlk->ngroups - 1, groups, nlk); | |
1da177e4 | 1486 | return err; |
4f520900 | 1487 | } |
1da177e4 LT |
1488 | } |
1489 | ||
4f520900 | 1490 | if (!groups && (nlk->groups == NULL || !(u32)nlk->groups[0])) |
1da177e4 LT |
1491 | return 0; |
1492 | ||
1493 | netlink_table_grab(); | |
f7fa9b10 | 1494 | netlink_update_subscriptions(sk, nlk->subscriptions + |
4f520900 | 1495 | hweight32(groups) - |
746fac4d | 1496 | hweight32(nlk->groups[0])); |
4f520900 | 1497 | nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | groups; |
4277a083 | 1498 | netlink_update_listeners(sk); |
1da177e4 LT |
1499 | netlink_table_ungrab(); |
1500 | ||
1501 | return 0; | |
1502 | } | |
1503 | ||
1504 | static int netlink_connect(struct socket *sock, struct sockaddr *addr, | |
1505 | int alen, int flags) | |
1506 | { | |
1507 | int err = 0; | |
1508 | struct sock *sk = sock->sk; | |
1509 | struct netlink_sock *nlk = nlk_sk(sk); | |
6ac552fd | 1510 | struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; |
1da177e4 | 1511 | |
6503d961 CG |
1512 | if (alen < sizeof(addr->sa_family)) |
1513 | return -EINVAL; | |
1514 | ||
1da177e4 LT |
1515 | if (addr->sa_family == AF_UNSPEC) { |
1516 | sk->sk_state = NETLINK_UNCONNECTED; | |
15e47304 | 1517 | nlk->dst_portid = 0; |
d629b836 | 1518 | nlk->dst_group = 0; |
1da177e4 LT |
1519 | return 0; |
1520 | } | |
1521 | if (addr->sa_family != AF_NETLINK) | |
1522 | return -EINVAL; | |
1523 | ||
46833a86 | 1524 | if ((nladdr->nl_groups || nladdr->nl_pid) && |
5187cd05 | 1525 | !netlink_allowed(sock, NL_CFG_F_NONROOT_SEND)) |
1da177e4 LT |
1526 | return -EPERM; |
1527 | ||
15e47304 | 1528 | if (!nlk->portid) |
1da177e4 LT |
1529 | err = netlink_autobind(sock); |
1530 | ||
1531 | if (err == 0) { | |
1532 | sk->sk_state = NETLINK_CONNECTED; | |
15e47304 | 1533 | nlk->dst_portid = nladdr->nl_pid; |
d629b836 | 1534 | nlk->dst_group = ffs(nladdr->nl_groups); |
1da177e4 LT |
1535 | } |
1536 | ||
1537 | return err; | |
1538 | } | |
1539 | ||
6ac552fd PM |
1540 | static int netlink_getname(struct socket *sock, struct sockaddr *addr, |
1541 | int *addr_len, int peer) | |
1da177e4 LT |
1542 | { |
1543 | struct sock *sk = sock->sk; | |
1544 | struct netlink_sock *nlk = nlk_sk(sk); | |
13cfa97b | 1545 | DECLARE_SOCKADDR(struct sockaddr_nl *, nladdr, addr); |
746fac4d | 1546 | |
1da177e4 LT |
1547 | nladdr->nl_family = AF_NETLINK; |
1548 | nladdr->nl_pad = 0; | |
1549 | *addr_len = sizeof(*nladdr); | |
1550 | ||
1551 | if (peer) { | |
15e47304 | 1552 | nladdr->nl_pid = nlk->dst_portid; |
d629b836 | 1553 | nladdr->nl_groups = netlink_group_mask(nlk->dst_group); |
1da177e4 | 1554 | } else { |
15e47304 | 1555 | nladdr->nl_pid = nlk->portid; |
513c2500 | 1556 | nladdr->nl_groups = nlk->groups ? nlk->groups[0] : 0; |
1da177e4 LT |
1557 | } |
1558 | return 0; | |
1559 | } | |
1560 | ||
15e47304 | 1561 | static struct sock *netlink_getsockbyportid(struct sock *ssk, u32 portid) |
1da177e4 | 1562 | { |
1da177e4 LT |
1563 | struct sock *sock; |
1564 | struct netlink_sock *nlk; | |
1565 | ||
15e47304 | 1566 | sock = netlink_lookup(sock_net(ssk), ssk->sk_protocol, portid); |
1da177e4 LT |
1567 | if (!sock) |
1568 | return ERR_PTR(-ECONNREFUSED); | |
1569 | ||
1570 | /* Don't bother queuing skb if kernel socket has no input function */ | |
1571 | nlk = nlk_sk(sock); | |
cd40b7d3 | 1572 | if (sock->sk_state == NETLINK_CONNECTED && |
15e47304 | 1573 | nlk->dst_portid != nlk_sk(ssk)->portid) { |
1da177e4 LT |
1574 | sock_put(sock); |
1575 | return ERR_PTR(-ECONNREFUSED); | |
1576 | } | |
1577 | return sock; | |
1578 | } | |
1579 | ||
1580 | struct sock *netlink_getsockbyfilp(struct file *filp) | |
1581 | { | |
496ad9aa | 1582 | struct inode *inode = file_inode(filp); |
1da177e4 LT |
1583 | struct sock *sock; |
1584 | ||
1585 | if (!S_ISSOCK(inode->i_mode)) | |
1586 | return ERR_PTR(-ENOTSOCK); | |
1587 | ||
1588 | sock = SOCKET_I(inode)->sk; | |
1589 | if (sock->sk_family != AF_NETLINK) | |
1590 | return ERR_PTR(-EINVAL); | |
1591 | ||
1592 | sock_hold(sock); | |
1593 | return sock; | |
1594 | } | |
1595 | ||
3a36515f PN |
1596 | static struct sk_buff *netlink_alloc_large_skb(unsigned int size, |
1597 | int broadcast) | |
c05cdb1b PNA |
1598 | { |
1599 | struct sk_buff *skb; | |
1600 | void *data; | |
1601 | ||
3a36515f | 1602 | if (size <= NLMSG_GOODSIZE || broadcast) |
c05cdb1b PNA |
1603 | return alloc_skb(size, GFP_KERNEL); |
1604 | ||
3a36515f PN |
1605 | size = SKB_DATA_ALIGN(size) + |
1606 | SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); | |
c05cdb1b PNA |
1607 | |
1608 | data = vmalloc(size); | |
1609 | if (data == NULL) | |
3a36515f | 1610 | return NULL; |
c05cdb1b | 1611 | |
3a36515f PN |
1612 | skb = build_skb(data, size); |
1613 | if (skb == NULL) | |
1614 | vfree(data); | |
1615 | else { | |
1616 | skb->head_frag = 0; | |
1617 | skb->destructor = netlink_skb_destructor; | |
1618 | } | |
c05cdb1b PNA |
1619 | |
1620 | return skb; | |
c05cdb1b PNA |
1621 | } |
1622 | ||
1da177e4 LT |
1623 | /* |
1624 | * Attach a skb to a netlink socket. | |
1625 | * The caller must hold a reference to the destination socket. On error, the | |
1626 | * reference is dropped. The skb is not send to the destination, just all | |
1627 | * all error checks are performed and memory in the queue is reserved. | |
1628 | * Return values: | |
1629 | * < 0: error. skb freed, reference to sock dropped. | |
1630 | * 0: continue | |
1631 | * 1: repeat lookup - reference dropped while waiting for socket memory. | |
1632 | */ | |
9457afee | 1633 | int netlink_attachskb(struct sock *sk, struct sk_buff *skb, |
c3d8d1e3 | 1634 | long *timeo, struct sock *ssk) |
1da177e4 LT |
1635 | { |
1636 | struct netlink_sock *nlk; | |
1637 | ||
1638 | nlk = nlk_sk(sk); | |
1639 | ||
5fd96123 PM |
1640 | if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || |
1641 | test_bit(NETLINK_CONGESTED, &nlk->state)) && | |
1642 | !netlink_skb_is_mmaped(skb)) { | |
1da177e4 | 1643 | DECLARE_WAITQUEUE(wait, current); |
c3d8d1e3 | 1644 | if (!*timeo) { |
aed81560 | 1645 | if (!ssk || netlink_is_kernel(ssk)) |
1da177e4 LT |
1646 | netlink_overrun(sk); |
1647 | sock_put(sk); | |
1648 | kfree_skb(skb); | |
1649 | return -EAGAIN; | |
1650 | } | |
1651 | ||
1652 | __set_current_state(TASK_INTERRUPTIBLE); | |
1653 | add_wait_queue(&nlk->wait, &wait); | |
1654 | ||
1655 | if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || | |
cd967e05 | 1656 | test_bit(NETLINK_CONGESTED, &nlk->state)) && |
1da177e4 | 1657 | !sock_flag(sk, SOCK_DEAD)) |
c3d8d1e3 | 1658 | *timeo = schedule_timeout(*timeo); |
1da177e4 LT |
1659 | |
1660 | __set_current_state(TASK_RUNNING); | |
1661 | remove_wait_queue(&nlk->wait, &wait); | |
1662 | sock_put(sk); | |
1663 | ||
1664 | if (signal_pending(current)) { | |
1665 | kfree_skb(skb); | |
c3d8d1e3 | 1666 | return sock_intr_errno(*timeo); |
1da177e4 LT |
1667 | } |
1668 | return 1; | |
1669 | } | |
cf0a018a | 1670 | netlink_skb_set_owner_r(skb, sk); |
1da177e4 LT |
1671 | return 0; |
1672 | } | |
1673 | ||
4a7e7c2a | 1674 | static int __netlink_sendskb(struct sock *sk, struct sk_buff *skb) |
1da177e4 | 1675 | { |
1da177e4 LT |
1676 | int len = skb->len; |
1677 | ||
bcbde0d4 DB |
1678 | netlink_deliver_tap(skb); |
1679 | ||
f9c22888 PM |
1680 | #ifdef CONFIG_NETLINK_MMAP |
1681 | if (netlink_skb_is_mmaped(skb)) | |
1682 | netlink_queue_mmaped_skb(sk, skb); | |
1683 | else if (netlink_rx_is_mmaped(sk)) | |
1684 | netlink_ring_set_copied(sk, skb); | |
1685 | else | |
1686 | #endif /* CONFIG_NETLINK_MMAP */ | |
1687 | skb_queue_tail(&sk->sk_receive_queue, skb); | |
676d2369 | 1688 | sk->sk_data_ready(sk); |
4a7e7c2a ED |
1689 | return len; |
1690 | } | |
1691 | ||
1692 | int netlink_sendskb(struct sock *sk, struct sk_buff *skb) | |
1693 | { | |
1694 | int len = __netlink_sendskb(sk, skb); | |
1695 | ||
1da177e4 LT |
1696 | sock_put(sk); |
1697 | return len; | |
1698 | } | |
1699 | ||
1700 | void netlink_detachskb(struct sock *sk, struct sk_buff *skb) | |
1701 | { | |
1702 | kfree_skb(skb); | |
1703 | sock_put(sk); | |
1704 | } | |
1705 | ||
b57ef81f | 1706 | static struct sk_buff *netlink_trim(struct sk_buff *skb, gfp_t allocation) |
1da177e4 LT |
1707 | { |
1708 | int delta; | |
1709 | ||
1298ca46 | 1710 | WARN_ON(skb->sk != NULL); |
5fd96123 PM |
1711 | if (netlink_skb_is_mmaped(skb)) |
1712 | return skb; | |
1da177e4 | 1713 | |
4305b541 | 1714 | delta = skb->end - skb->tail; |
c05cdb1b | 1715 | if (is_vmalloc_addr(skb->head) || delta * 2 < skb->truesize) |
1da177e4 LT |
1716 | return skb; |
1717 | ||
1718 | if (skb_shared(skb)) { | |
1719 | struct sk_buff *nskb = skb_clone(skb, allocation); | |
1720 | if (!nskb) | |
1721 | return skb; | |
8460c00f | 1722 | consume_skb(skb); |
1da177e4 LT |
1723 | skb = nskb; |
1724 | } | |
1725 | ||
1726 | if (!pskb_expand_head(skb, 0, -delta, allocation)) | |
1727 | skb->truesize -= delta; | |
1728 | ||
1729 | return skb; | |
1730 | } | |
1731 | ||
3fbc2905 EB |
1732 | static int netlink_unicast_kernel(struct sock *sk, struct sk_buff *skb, |
1733 | struct sock *ssk) | |
cd40b7d3 DL |
1734 | { |
1735 | int ret; | |
1736 | struct netlink_sock *nlk = nlk_sk(sk); | |
1737 | ||
1738 | ret = -ECONNREFUSED; | |
1739 | if (nlk->netlink_rcv != NULL) { | |
1740 | ret = skb->len; | |
cf0a018a | 1741 | netlink_skb_set_owner_r(skb, sk); |
e32123e5 | 1742 | NETLINK_CB(skb).sk = ssk; |
73bfd370 | 1743 | netlink_deliver_tap_kernel(sk, ssk, skb); |
cd40b7d3 | 1744 | nlk->netlink_rcv(skb); |
bfb253c9 ED |
1745 | consume_skb(skb); |
1746 | } else { | |
1747 | kfree_skb(skb); | |
cd40b7d3 | 1748 | } |
cd40b7d3 DL |
1749 | sock_put(sk); |
1750 | return ret; | |
1751 | } | |
1752 | ||
1753 | int netlink_unicast(struct sock *ssk, struct sk_buff *skb, | |
15e47304 | 1754 | u32 portid, int nonblock) |
1da177e4 LT |
1755 | { |
1756 | struct sock *sk; | |
1757 | int err; | |
1758 | long timeo; | |
1759 | ||
1760 | skb = netlink_trim(skb, gfp_any()); | |
1761 | ||
1762 | timeo = sock_sndtimeo(ssk, nonblock); | |
1763 | retry: | |
15e47304 | 1764 | sk = netlink_getsockbyportid(ssk, portid); |
1da177e4 LT |
1765 | if (IS_ERR(sk)) { |
1766 | kfree_skb(skb); | |
1767 | return PTR_ERR(sk); | |
1768 | } | |
cd40b7d3 | 1769 | if (netlink_is_kernel(sk)) |
3fbc2905 | 1770 | return netlink_unicast_kernel(sk, skb, ssk); |
cd40b7d3 | 1771 | |
b1153f29 | 1772 | if (sk_filter(sk, skb)) { |
84874607 | 1773 | err = skb->len; |
b1153f29 SH |
1774 | kfree_skb(skb); |
1775 | sock_put(sk); | |
1776 | return err; | |
1777 | } | |
1778 | ||
9457afee | 1779 | err = netlink_attachskb(sk, skb, &timeo, ssk); |
1da177e4 LT |
1780 | if (err == 1) |
1781 | goto retry; | |
1782 | if (err) | |
1783 | return err; | |
1784 | ||
7ee015e0 | 1785 | return netlink_sendskb(sk, skb); |
1da177e4 | 1786 | } |
6ac552fd | 1787 | EXPORT_SYMBOL(netlink_unicast); |
1da177e4 | 1788 | |
f9c22888 PM |
1789 | struct sk_buff *netlink_alloc_skb(struct sock *ssk, unsigned int size, |
1790 | u32 dst_portid, gfp_t gfp_mask) | |
1791 | { | |
1792 | #ifdef CONFIG_NETLINK_MMAP | |
1793 | struct sock *sk = NULL; | |
1794 | struct sk_buff *skb; | |
1795 | struct netlink_ring *ring; | |
1796 | struct nl_mmap_hdr *hdr; | |
1797 | unsigned int maxlen; | |
1798 | ||
1799 | sk = netlink_getsockbyportid(ssk, dst_portid); | |
1800 | if (IS_ERR(sk)) | |
1801 | goto out; | |
1802 | ||
1803 | ring = &nlk_sk(sk)->rx_ring; | |
1804 | /* fast-path without atomic ops for common case: non-mmaped receiver */ | |
1805 | if (ring->pg_vec == NULL) | |
1806 | goto out_put; | |
1807 | ||
aae9f0e2 TG |
1808 | if (ring->frame_size - NL_MMAP_HDRLEN < size) |
1809 | goto out_put; | |
1810 | ||
f9c22888 PM |
1811 | skb = alloc_skb_head(gfp_mask); |
1812 | if (skb == NULL) | |
1813 | goto err1; | |
1814 | ||
1815 | spin_lock_bh(&sk->sk_receive_queue.lock); | |
1816 | /* check again under lock */ | |
1817 | if (ring->pg_vec == NULL) | |
1818 | goto out_free; | |
1819 | ||
aae9f0e2 | 1820 | /* check again under lock */ |
f9c22888 PM |
1821 | maxlen = ring->frame_size - NL_MMAP_HDRLEN; |
1822 | if (maxlen < size) | |
1823 | goto out_free; | |
1824 | ||
1825 | netlink_forward_ring(ring); | |
1826 | hdr = netlink_current_frame(ring, NL_MMAP_STATUS_UNUSED); | |
1827 | if (hdr == NULL) | |
1828 | goto err2; | |
1829 | netlink_ring_setup_skb(skb, sk, ring, hdr); | |
1830 | netlink_set_status(hdr, NL_MMAP_STATUS_RESERVED); | |
1831 | atomic_inc(&ring->pending); | |
1832 | netlink_increment_head(ring); | |
1833 | ||
1834 | spin_unlock_bh(&sk->sk_receive_queue.lock); | |
1835 | return skb; | |
1836 | ||
1837 | err2: | |
1838 | kfree_skb(skb); | |
1839 | spin_unlock_bh(&sk->sk_receive_queue.lock); | |
cd1df525 | 1840 | netlink_overrun(sk); |
f9c22888 PM |
1841 | err1: |
1842 | sock_put(sk); | |
1843 | return NULL; | |
1844 | ||
1845 | out_free: | |
1846 | kfree_skb(skb); | |
1847 | spin_unlock_bh(&sk->sk_receive_queue.lock); | |
1848 | out_put: | |
1849 | sock_put(sk); | |
1850 | out: | |
1851 | #endif | |
1852 | return alloc_skb(size, gfp_mask); | |
1853 | } | |
1854 | EXPORT_SYMBOL_GPL(netlink_alloc_skb); | |
1855 | ||
4277a083 PM |
1856 | int netlink_has_listeners(struct sock *sk, unsigned int group) |
1857 | { | |
1858 | int res = 0; | |
5c398dc8 | 1859 | struct listeners *listeners; |
4277a083 | 1860 | |
aed81560 | 1861 | BUG_ON(!netlink_is_kernel(sk)); |
b4ff4f04 JB |
1862 | |
1863 | rcu_read_lock(); | |
1864 | listeners = rcu_dereference(nl_table[sk->sk_protocol].listeners); | |
1865 | ||
6d772ac5 | 1866 | if (listeners && group - 1 < nl_table[sk->sk_protocol].groups) |
5c398dc8 | 1867 | res = test_bit(group - 1, listeners->masks); |
b4ff4f04 JB |
1868 | |
1869 | rcu_read_unlock(); | |
1870 | ||
4277a083 PM |
1871 | return res; |
1872 | } | |
1873 | EXPORT_SYMBOL_GPL(netlink_has_listeners); | |
1874 | ||
b57ef81f | 1875 | static int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb) |
1da177e4 LT |
1876 | { |
1877 | struct netlink_sock *nlk = nlk_sk(sk); | |
1878 | ||
1879 | if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf && | |
cd967e05 | 1880 | !test_bit(NETLINK_CONGESTED, &nlk->state)) { |
cf0a018a | 1881 | netlink_skb_set_owner_r(skb, sk); |
4a7e7c2a | 1882 | __netlink_sendskb(sk, skb); |
2c645800 | 1883 | return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1); |
1da177e4 LT |
1884 | } |
1885 | return -1; | |
1886 | } | |
1887 | ||
1888 | struct netlink_broadcast_data { | |
1889 | struct sock *exclude_sk; | |
b4b51029 | 1890 | struct net *net; |
15e47304 | 1891 | u32 portid; |
1da177e4 LT |
1892 | u32 group; |
1893 | int failure; | |
ff491a73 | 1894 | int delivery_failure; |
1da177e4 LT |
1895 | int congested; |
1896 | int delivered; | |
7d877f3b | 1897 | gfp_t allocation; |
1da177e4 | 1898 | struct sk_buff *skb, *skb2; |
910a7e90 EB |
1899 | int (*tx_filter)(struct sock *dsk, struct sk_buff *skb, void *data); |
1900 | void *tx_data; | |
1da177e4 LT |
1901 | }; |
1902 | ||
46c9521f RR |
1903 | static void do_one_broadcast(struct sock *sk, |
1904 | struct netlink_broadcast_data *p) | |
1da177e4 LT |
1905 | { |
1906 | struct netlink_sock *nlk = nlk_sk(sk); | |
1907 | int val; | |
1908 | ||
1909 | if (p->exclude_sk == sk) | |
46c9521f | 1910 | return; |
1da177e4 | 1911 | |
15e47304 | 1912 | if (nlk->portid == p->portid || p->group - 1 >= nlk->ngroups || |
f7fa9b10 | 1913 | !test_bit(p->group - 1, nlk->groups)) |
46c9521f | 1914 | return; |
1da177e4 | 1915 | |
878628fb | 1916 | if (!net_eq(sock_net(sk), p->net)) |
46c9521f | 1917 | return; |
b4b51029 | 1918 | |
1da177e4 LT |
1919 | if (p->failure) { |
1920 | netlink_overrun(sk); | |
46c9521f | 1921 | return; |
1da177e4 LT |
1922 | } |
1923 | ||
1924 | sock_hold(sk); | |
1925 | if (p->skb2 == NULL) { | |
68acc024 | 1926 | if (skb_shared(p->skb)) { |
1da177e4 LT |
1927 | p->skb2 = skb_clone(p->skb, p->allocation); |
1928 | } else { | |
68acc024 TC |
1929 | p->skb2 = skb_get(p->skb); |
1930 | /* | |
1931 | * skb ownership may have been set when | |
1932 | * delivered to a previous socket. | |
1933 | */ | |
1934 | skb_orphan(p->skb2); | |
1da177e4 LT |
1935 | } |
1936 | } | |
1937 | if (p->skb2 == NULL) { | |
1938 | netlink_overrun(sk); | |
1939 | /* Clone failed. Notify ALL listeners. */ | |
1940 | p->failure = 1; | |
be0c22a4 PNA |
1941 | if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR) |
1942 | p->delivery_failure = 1; | |
910a7e90 EB |
1943 | } else if (p->tx_filter && p->tx_filter(sk, p->skb2, p->tx_data)) { |
1944 | kfree_skb(p->skb2); | |
1945 | p->skb2 = NULL; | |
b1153f29 SH |
1946 | } else if (sk_filter(sk, p->skb2)) { |
1947 | kfree_skb(p->skb2); | |
1948 | p->skb2 = NULL; | |
1da177e4 LT |
1949 | } else if ((val = netlink_broadcast_deliver(sk, p->skb2)) < 0) { |
1950 | netlink_overrun(sk); | |
be0c22a4 PNA |
1951 | if (nlk->flags & NETLINK_BROADCAST_SEND_ERROR) |
1952 | p->delivery_failure = 1; | |
1da177e4 LT |
1953 | } else { |
1954 | p->congested |= val; | |
1955 | p->delivered = 1; | |
1956 | p->skb2 = NULL; | |
1957 | } | |
1958 | sock_put(sk); | |
1da177e4 LT |
1959 | } |
1960 | ||
15e47304 | 1961 | int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, u32 portid, |
910a7e90 EB |
1962 | u32 group, gfp_t allocation, |
1963 | int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data), | |
1964 | void *filter_data) | |
1da177e4 | 1965 | { |
3b1e0a65 | 1966 | struct net *net = sock_net(ssk); |
1da177e4 | 1967 | struct netlink_broadcast_data info; |
1da177e4 LT |
1968 | struct sock *sk; |
1969 | ||
1970 | skb = netlink_trim(skb, allocation); | |
1971 | ||
1972 | info.exclude_sk = ssk; | |
b4b51029 | 1973 | info.net = net; |
15e47304 | 1974 | info.portid = portid; |
1da177e4 LT |
1975 | info.group = group; |
1976 | info.failure = 0; | |
ff491a73 | 1977 | info.delivery_failure = 0; |
1da177e4 LT |
1978 | info.congested = 0; |
1979 | info.delivered = 0; | |
1980 | info.allocation = allocation; | |
1981 | info.skb = skb; | |
1982 | info.skb2 = NULL; | |
910a7e90 EB |
1983 | info.tx_filter = filter; |
1984 | info.tx_data = filter_data; | |
1da177e4 LT |
1985 | |
1986 | /* While we sleep in clone, do not allow to change socket list */ | |
1987 | ||
1988 | netlink_lock_table(); | |
1989 | ||
b67bfe0d | 1990 | sk_for_each_bound(sk, &nl_table[ssk->sk_protocol].mc_list) |
1da177e4 LT |
1991 | do_one_broadcast(sk, &info); |
1992 | ||
70d4bf6d | 1993 | consume_skb(skb); |
aa1c6a6f | 1994 | |
1da177e4 LT |
1995 | netlink_unlock_table(); |
1996 | ||
70d4bf6d NH |
1997 | if (info.delivery_failure) { |
1998 | kfree_skb(info.skb2); | |
ff491a73 | 1999 | return -ENOBUFS; |
658cb354 ED |
2000 | } |
2001 | consume_skb(info.skb2); | |
ff491a73 | 2002 | |
1da177e4 LT |
2003 | if (info.delivered) { |
2004 | if (info.congested && (allocation & __GFP_WAIT)) | |
2005 | yield(); | |
2006 | return 0; | |
2007 | } | |
1da177e4 LT |
2008 | return -ESRCH; |
2009 | } | |
910a7e90 EB |
2010 | EXPORT_SYMBOL(netlink_broadcast_filtered); |
2011 | ||
15e47304 | 2012 | int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 portid, |
910a7e90 EB |
2013 | u32 group, gfp_t allocation) |
2014 | { | |
15e47304 | 2015 | return netlink_broadcast_filtered(ssk, skb, portid, group, allocation, |
910a7e90 EB |
2016 | NULL, NULL); |
2017 | } | |
6ac552fd | 2018 | EXPORT_SYMBOL(netlink_broadcast); |
1da177e4 LT |
2019 | |
2020 | struct netlink_set_err_data { | |
2021 | struct sock *exclude_sk; | |
15e47304 | 2022 | u32 portid; |
1da177e4 LT |
2023 | u32 group; |
2024 | int code; | |
2025 | }; | |
2026 | ||
b57ef81f | 2027 | static int do_one_set_err(struct sock *sk, struct netlink_set_err_data *p) |
1da177e4 LT |
2028 | { |
2029 | struct netlink_sock *nlk = nlk_sk(sk); | |
1a50307b | 2030 | int ret = 0; |
1da177e4 LT |
2031 | |
2032 | if (sk == p->exclude_sk) | |
2033 | goto out; | |
2034 | ||
09ad9bc7 | 2035 | if (!net_eq(sock_net(sk), sock_net(p->exclude_sk))) |
b4b51029 EB |
2036 | goto out; |
2037 | ||
15e47304 | 2038 | if (nlk->portid == p->portid || p->group - 1 >= nlk->ngroups || |
f7fa9b10 | 2039 | !test_bit(p->group - 1, nlk->groups)) |
1da177e4 LT |
2040 | goto out; |
2041 | ||
1a50307b PNA |
2042 | if (p->code == ENOBUFS && nlk->flags & NETLINK_RECV_NO_ENOBUFS) { |
2043 | ret = 1; | |
2044 | goto out; | |
2045 | } | |
2046 | ||
1da177e4 LT |
2047 | sk->sk_err = p->code; |
2048 | sk->sk_error_report(sk); | |
2049 | out: | |
1a50307b | 2050 | return ret; |
1da177e4 LT |
2051 | } |
2052 | ||
4843b93c PNA |
2053 | /** |
2054 | * netlink_set_err - report error to broadcast listeners | |
2055 | * @ssk: the kernel netlink socket, as returned by netlink_kernel_create() | |
15e47304 | 2056 | * @portid: the PORTID of a process that we want to skip (if any) |
840e93f2 | 2057 | * @group: the broadcast group that will notice the error |
4843b93c | 2058 | * @code: error code, must be negative (as usual in kernelspace) |
1a50307b PNA |
2059 | * |
2060 | * This function returns the number of broadcast listeners that have set the | |
2061 | * NETLINK_RECV_NO_ENOBUFS socket option. | |
4843b93c | 2062 | */ |
15e47304 | 2063 | int netlink_set_err(struct sock *ssk, u32 portid, u32 group, int code) |
1da177e4 LT |
2064 | { |
2065 | struct netlink_set_err_data info; | |
1da177e4 | 2066 | struct sock *sk; |
1a50307b | 2067 | int ret = 0; |
1da177e4 LT |
2068 | |
2069 | info.exclude_sk = ssk; | |
15e47304 | 2070 | info.portid = portid; |
1da177e4 | 2071 | info.group = group; |
4843b93c PNA |
2072 | /* sk->sk_err wants a positive error value */ |
2073 | info.code = -code; | |
1da177e4 LT |
2074 | |
2075 | read_lock(&nl_table_lock); | |
2076 | ||
b67bfe0d | 2077 | sk_for_each_bound(sk, &nl_table[ssk->sk_protocol].mc_list) |
1a50307b | 2078 | ret += do_one_set_err(sk, &info); |
1da177e4 LT |
2079 | |
2080 | read_unlock(&nl_table_lock); | |
1a50307b | 2081 | return ret; |
1da177e4 | 2082 | } |
dd5b6ce6 | 2083 | EXPORT_SYMBOL(netlink_set_err); |
1da177e4 | 2084 | |
84659eb5 JB |
2085 | /* must be called with netlink table grabbed */ |
2086 | static void netlink_update_socket_mc(struct netlink_sock *nlk, | |
2087 | unsigned int group, | |
2088 | int is_new) | |
2089 | { | |
2090 | int old, new = !!is_new, subscriptions; | |
2091 | ||
2092 | old = test_bit(group - 1, nlk->groups); | |
2093 | subscriptions = nlk->subscriptions - old + new; | |
2094 | if (new) | |
2095 | __set_bit(group - 1, nlk->groups); | |
2096 | else | |
2097 | __clear_bit(group - 1, nlk->groups); | |
2098 | netlink_update_subscriptions(&nlk->sk, subscriptions); | |
2099 | netlink_update_listeners(&nlk->sk); | |
2100 | } | |
2101 | ||
9a4595bc | 2102 | static int netlink_setsockopt(struct socket *sock, int level, int optname, |
b7058842 | 2103 | char __user *optval, unsigned int optlen) |
9a4595bc PM |
2104 | { |
2105 | struct sock *sk = sock->sk; | |
2106 | struct netlink_sock *nlk = nlk_sk(sk); | |
eb496534 JB |
2107 | unsigned int val = 0; |
2108 | int err; | |
9a4595bc PM |
2109 | |
2110 | if (level != SOL_NETLINK) | |
2111 | return -ENOPROTOOPT; | |
2112 | ||
ccdfcc39 PM |
2113 | if (optname != NETLINK_RX_RING && optname != NETLINK_TX_RING && |
2114 | optlen >= sizeof(int) && | |
eb496534 | 2115 | get_user(val, (unsigned int __user *)optval)) |
9a4595bc PM |
2116 | return -EFAULT; |
2117 | ||
2118 | switch (optname) { | |
2119 | case NETLINK_PKTINFO: | |
2120 | if (val) | |
2121 | nlk->flags |= NETLINK_RECV_PKTINFO; | |
2122 | else | |
2123 | nlk->flags &= ~NETLINK_RECV_PKTINFO; | |
2124 | err = 0; | |
2125 | break; | |
2126 | case NETLINK_ADD_MEMBERSHIP: | |
2127 | case NETLINK_DROP_MEMBERSHIP: { | |
5187cd05 | 2128 | if (!netlink_allowed(sock, NL_CFG_F_NONROOT_RECV)) |
9a4595bc | 2129 | return -EPERM; |
b4ff4f04 JB |
2130 | err = netlink_realloc_groups(sk); |
2131 | if (err) | |
2132 | return err; | |
9a4595bc PM |
2133 | if (!val || val - 1 >= nlk->ngroups) |
2134 | return -EINVAL; | |
7774d5e0 | 2135 | if (optname == NETLINK_ADD_MEMBERSHIP && nlk->netlink_bind) { |
4f520900 RGB |
2136 | err = nlk->netlink_bind(val); |
2137 | if (err) | |
2138 | return err; | |
2139 | } | |
9a4595bc | 2140 | netlink_table_grab(); |
84659eb5 JB |
2141 | netlink_update_socket_mc(nlk, val, |
2142 | optname == NETLINK_ADD_MEMBERSHIP); | |
9a4595bc | 2143 | netlink_table_ungrab(); |
7774d5e0 RGB |
2144 | if (optname == NETLINK_DROP_MEMBERSHIP && nlk->netlink_unbind) |
2145 | nlk->netlink_unbind(val); | |
03292745 | 2146 | |
9a4595bc PM |
2147 | err = 0; |
2148 | break; | |
2149 | } | |
be0c22a4 PNA |
2150 | case NETLINK_BROADCAST_ERROR: |
2151 | if (val) | |
2152 | nlk->flags |= NETLINK_BROADCAST_SEND_ERROR; | |
2153 | else | |
2154 | nlk->flags &= ~NETLINK_BROADCAST_SEND_ERROR; | |
2155 | err = 0; | |
2156 | break; | |
38938bfe PNA |
2157 | case NETLINK_NO_ENOBUFS: |
2158 | if (val) { | |
2159 | nlk->flags |= NETLINK_RECV_NO_ENOBUFS; | |
cd967e05 | 2160 | clear_bit(NETLINK_CONGESTED, &nlk->state); |
38938bfe | 2161 | wake_up_interruptible(&nlk->wait); |
658cb354 | 2162 | } else { |
38938bfe | 2163 | nlk->flags &= ~NETLINK_RECV_NO_ENOBUFS; |
658cb354 | 2164 | } |
38938bfe PNA |
2165 | err = 0; |
2166 | break; | |
ccdfcc39 PM |
2167 | #ifdef CONFIG_NETLINK_MMAP |
2168 | case NETLINK_RX_RING: | |
2169 | case NETLINK_TX_RING: { | |
2170 | struct nl_mmap_req req; | |
2171 | ||
2172 | /* Rings might consume more memory than queue limits, require | |
2173 | * CAP_NET_ADMIN. | |
2174 | */ | |
2175 | if (!capable(CAP_NET_ADMIN)) | |
2176 | return -EPERM; | |
2177 | if (optlen < sizeof(req)) | |
2178 | return -EINVAL; | |
2179 | if (copy_from_user(&req, optval, sizeof(req))) | |
2180 | return -EFAULT; | |
2181 | err = netlink_set_ring(sk, &req, false, | |
2182 | optname == NETLINK_TX_RING); | |
2183 | break; | |
2184 | } | |
2185 | #endif /* CONFIG_NETLINK_MMAP */ | |
9a4595bc PM |
2186 | default: |
2187 | err = -ENOPROTOOPT; | |
2188 | } | |
2189 | return err; | |
2190 | } | |
2191 | ||
2192 | static int netlink_getsockopt(struct socket *sock, int level, int optname, | |
746fac4d | 2193 | char __user *optval, int __user *optlen) |
9a4595bc PM |
2194 | { |
2195 | struct sock *sk = sock->sk; | |
2196 | struct netlink_sock *nlk = nlk_sk(sk); | |
2197 | int len, val, err; | |
2198 | ||
2199 | if (level != SOL_NETLINK) | |
2200 | return -ENOPROTOOPT; | |
2201 | ||
2202 | if (get_user(len, optlen)) | |
2203 | return -EFAULT; | |
2204 | if (len < 0) | |
2205 | return -EINVAL; | |
2206 | ||
2207 | switch (optname) { | |
2208 | case NETLINK_PKTINFO: | |
2209 | if (len < sizeof(int)) | |
2210 | return -EINVAL; | |
2211 | len = sizeof(int); | |
2212 | val = nlk->flags & NETLINK_RECV_PKTINFO ? 1 : 0; | |
a27b58fe HC |
2213 | if (put_user(len, optlen) || |
2214 | put_user(val, optval)) | |
2215 | return -EFAULT; | |
9a4595bc PM |
2216 | err = 0; |
2217 | break; | |
be0c22a4 PNA |
2218 | case NETLINK_BROADCAST_ERROR: |
2219 | if (len < sizeof(int)) | |
2220 | return -EINVAL; | |
2221 | len = sizeof(int); | |
2222 | val = nlk->flags & NETLINK_BROADCAST_SEND_ERROR ? 1 : 0; | |
2223 | if (put_user(len, optlen) || | |
2224 | put_user(val, optval)) | |
2225 | return -EFAULT; | |
2226 | err = 0; | |
2227 | break; | |
38938bfe PNA |
2228 | case NETLINK_NO_ENOBUFS: |
2229 | if (len < sizeof(int)) | |
2230 | return -EINVAL; | |
2231 | len = sizeof(int); | |
2232 | val = nlk->flags & NETLINK_RECV_NO_ENOBUFS ? 1 : 0; | |
2233 | if (put_user(len, optlen) || | |
2234 | put_user(val, optval)) | |
2235 | return -EFAULT; | |
2236 | err = 0; | |
2237 | break; | |
9a4595bc PM |
2238 | default: |
2239 | err = -ENOPROTOOPT; | |
2240 | } | |
2241 | return err; | |
2242 | } | |
2243 | ||
2244 | static void netlink_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb) | |
2245 | { | |
2246 | struct nl_pktinfo info; | |
2247 | ||
2248 | info.group = NETLINK_CB(skb).dst_group; | |
2249 | put_cmsg(msg, SOL_NETLINK, NETLINK_PKTINFO, sizeof(info), &info); | |
2250 | } | |
2251 | ||
1da177e4 LT |
2252 | static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock, |
2253 | struct msghdr *msg, size_t len) | |
2254 | { | |
2255 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
2256 | struct sock *sk = sock->sk; | |
2257 | struct netlink_sock *nlk = nlk_sk(sk); | |
342dfc30 | 2258 | DECLARE_SOCKADDR(struct sockaddr_nl *, addr, msg->msg_name); |
15e47304 | 2259 | u32 dst_portid; |
d629b836 | 2260 | u32 dst_group; |
1da177e4 LT |
2261 | struct sk_buff *skb; |
2262 | int err; | |
2263 | struct scm_cookie scm; | |
2d7a85f4 | 2264 | u32 netlink_skb_flags = 0; |
1da177e4 LT |
2265 | |
2266 | if (msg->msg_flags&MSG_OOB) | |
2267 | return -EOPNOTSUPP; | |
2268 | ||
16e57262 | 2269 | if (NULL == siocb->scm) |
1da177e4 | 2270 | siocb->scm = &scm; |
16e57262 | 2271 | |
e0e3cea4 | 2272 | err = scm_send(sock, msg, siocb->scm, true); |
1da177e4 LT |
2273 | if (err < 0) |
2274 | return err; | |
2275 | ||
2276 | if (msg->msg_namelen) { | |
b47030c7 | 2277 | err = -EINVAL; |
1da177e4 | 2278 | if (addr->nl_family != AF_NETLINK) |
b47030c7 | 2279 | goto out; |
15e47304 | 2280 | dst_portid = addr->nl_pid; |
d629b836 | 2281 | dst_group = ffs(addr->nl_groups); |
b47030c7 | 2282 | err = -EPERM; |
15e47304 | 2283 | if ((dst_group || dst_portid) && |
5187cd05 | 2284 | !netlink_allowed(sock, NL_CFG_F_NONROOT_SEND)) |
b47030c7 | 2285 | goto out; |
2d7a85f4 | 2286 | netlink_skb_flags |= NETLINK_SKB_DST; |
1da177e4 | 2287 | } else { |
15e47304 | 2288 | dst_portid = nlk->dst_portid; |
d629b836 | 2289 | dst_group = nlk->dst_group; |
1da177e4 LT |
2290 | } |
2291 | ||
15e47304 | 2292 | if (!nlk->portid) { |
1da177e4 LT |
2293 | err = netlink_autobind(sock); |
2294 | if (err) | |
2295 | goto out; | |
2296 | } | |
2297 | ||
5fd96123 PM |
2298 | if (netlink_tx_is_mmaped(sk) && |
2299 | msg->msg_iov->iov_base == NULL) { | |
2300 | err = netlink_mmap_sendmsg(sk, msg, dst_portid, dst_group, | |
2301 | siocb); | |
2302 | goto out; | |
2303 | } | |
2304 | ||
1da177e4 LT |
2305 | err = -EMSGSIZE; |
2306 | if (len > sk->sk_sndbuf - 32) | |
2307 | goto out; | |
2308 | err = -ENOBUFS; | |
3a36515f | 2309 | skb = netlink_alloc_large_skb(len, dst_group); |
6ac552fd | 2310 | if (skb == NULL) |
1da177e4 LT |
2311 | goto out; |
2312 | ||
15e47304 | 2313 | NETLINK_CB(skb).portid = nlk->portid; |
d629b836 | 2314 | NETLINK_CB(skb).dst_group = dst_group; |
dbe9a417 | 2315 | NETLINK_CB(skb).creds = siocb->scm->creds; |
2d7a85f4 | 2316 | NETLINK_CB(skb).flags = netlink_skb_flags; |
1da177e4 | 2317 | |
1da177e4 | 2318 | err = -EFAULT; |
6ac552fd | 2319 | if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) { |
1da177e4 LT |
2320 | kfree_skb(skb); |
2321 | goto out; | |
2322 | } | |
2323 | ||
2324 | err = security_netlink_send(sk, skb); | |
2325 | if (err) { | |
2326 | kfree_skb(skb); | |
2327 | goto out; | |
2328 | } | |
2329 | ||
d629b836 | 2330 | if (dst_group) { |
1da177e4 | 2331 | atomic_inc(&skb->users); |
15e47304 | 2332 | netlink_broadcast(sk, skb, dst_portid, dst_group, GFP_KERNEL); |
1da177e4 | 2333 | } |
15e47304 | 2334 | err = netlink_unicast(sk, skb, dst_portid, msg->msg_flags&MSG_DONTWAIT); |
1da177e4 LT |
2335 | |
2336 | out: | |
b47030c7 | 2337 | scm_destroy(siocb->scm); |
1da177e4 LT |
2338 | return err; |
2339 | } | |
2340 | ||
2341 | static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock, | |
2342 | struct msghdr *msg, size_t len, | |
2343 | int flags) | |
2344 | { | |
2345 | struct sock_iocb *siocb = kiocb_to_siocb(kiocb); | |
2346 | struct scm_cookie scm; | |
2347 | struct sock *sk = sock->sk; | |
2348 | struct netlink_sock *nlk = nlk_sk(sk); | |
2349 | int noblock = flags&MSG_DONTWAIT; | |
2350 | size_t copied; | |
68d6ac6d | 2351 | struct sk_buff *skb, *data_skb; |
b44d211e | 2352 | int err, ret; |
1da177e4 LT |
2353 | |
2354 | if (flags&MSG_OOB) | |
2355 | return -EOPNOTSUPP; | |
2356 | ||
2357 | copied = 0; | |
2358 | ||
6ac552fd PM |
2359 | skb = skb_recv_datagram(sk, flags, noblock, &err); |
2360 | if (skb == NULL) | |
1da177e4 LT |
2361 | goto out; |
2362 | ||
68d6ac6d JB |
2363 | data_skb = skb; |
2364 | ||
1dacc76d JB |
2365 | #ifdef CONFIG_COMPAT_NETLINK_MESSAGES |
2366 | if (unlikely(skb_shinfo(skb)->frag_list)) { | |
1dacc76d | 2367 | /* |
68d6ac6d JB |
2368 | * If this skb has a frag_list, then here that means that we |
2369 | * will have to use the frag_list skb's data for compat tasks | |
2370 | * and the regular skb's data for normal (non-compat) tasks. | |
1dacc76d | 2371 | * |
68d6ac6d JB |
2372 | * If we need to send the compat skb, assign it to the |
2373 | * 'data_skb' variable so that it will be used below for data | |
2374 | * copying. We keep 'skb' for everything else, including | |
2375 | * freeing both later. | |
1dacc76d | 2376 | */ |
68d6ac6d JB |
2377 | if (flags & MSG_CMSG_COMPAT) |
2378 | data_skb = skb_shinfo(skb)->frag_list; | |
1dacc76d JB |
2379 | } |
2380 | #endif | |
2381 | ||
9063e21f ED |
2382 | /* Record the max length of recvmsg() calls for future allocations */ |
2383 | nlk->max_recvmsg_len = max(nlk->max_recvmsg_len, len); | |
2384 | nlk->max_recvmsg_len = min_t(size_t, nlk->max_recvmsg_len, | |
2385 | 16384); | |
2386 | ||
68d6ac6d | 2387 | copied = data_skb->len; |
1da177e4 LT |
2388 | if (len < copied) { |
2389 | msg->msg_flags |= MSG_TRUNC; | |
2390 | copied = len; | |
2391 | } | |
2392 | ||
68d6ac6d JB |
2393 | skb_reset_transport_header(data_skb); |
2394 | err = skb_copy_datagram_iovec(data_skb, 0, msg->msg_iov, copied); | |
1da177e4 LT |
2395 | |
2396 | if (msg->msg_name) { | |
342dfc30 | 2397 | DECLARE_SOCKADDR(struct sockaddr_nl *, addr, msg->msg_name); |
1da177e4 LT |
2398 | addr->nl_family = AF_NETLINK; |
2399 | addr->nl_pad = 0; | |
15e47304 | 2400 | addr->nl_pid = NETLINK_CB(skb).portid; |
d629b836 | 2401 | addr->nl_groups = netlink_group_mask(NETLINK_CB(skb).dst_group); |
1da177e4 LT |
2402 | msg->msg_namelen = sizeof(*addr); |
2403 | } | |
2404 | ||
cc9a06cd PM |
2405 | if (nlk->flags & NETLINK_RECV_PKTINFO) |
2406 | netlink_cmsg_recv_pktinfo(msg, skb); | |
2407 | ||
1da177e4 LT |
2408 | if (NULL == siocb->scm) { |
2409 | memset(&scm, 0, sizeof(scm)); | |
2410 | siocb->scm = &scm; | |
2411 | } | |
2412 | siocb->scm->creds = *NETLINK_CREDS(skb); | |
188ccb55 | 2413 | if (flags & MSG_TRUNC) |
68d6ac6d | 2414 | copied = data_skb->len; |
daa3766e | 2415 | |
1da177e4 LT |
2416 | skb_free_datagram(sk, skb); |
2417 | ||
16b304f3 PS |
2418 | if (nlk->cb_running && |
2419 | atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) { | |
b44d211e AV |
2420 | ret = netlink_dump(sk); |
2421 | if (ret) { | |
ac30ef83 | 2422 | sk->sk_err = -ret; |
b44d211e AV |
2423 | sk->sk_error_report(sk); |
2424 | } | |
2425 | } | |
1da177e4 LT |
2426 | |
2427 | scm_recv(sock, msg, siocb->scm, flags); | |
1da177e4 LT |
2428 | out: |
2429 | netlink_rcv_wake(sk); | |
2430 | return err ? : copied; | |
2431 | } | |
2432 | ||
676d2369 | 2433 | static void netlink_data_ready(struct sock *sk) |
1da177e4 | 2434 | { |
cd40b7d3 | 2435 | BUG(); |
1da177e4 LT |
2436 | } |
2437 | ||
2438 | /* | |
746fac4d | 2439 | * We export these functions to other modules. They provide a |
1da177e4 LT |
2440 | * complete set of kernel non-blocking support for message |
2441 | * queueing. | |
2442 | */ | |
2443 | ||
2444 | struct sock * | |
9f00d977 PNA |
2445 | __netlink_kernel_create(struct net *net, int unit, struct module *module, |
2446 | struct netlink_kernel_cfg *cfg) | |
1da177e4 LT |
2447 | { |
2448 | struct socket *sock; | |
2449 | struct sock *sk; | |
77247bbb | 2450 | struct netlink_sock *nlk; |
5c398dc8 | 2451 | struct listeners *listeners = NULL; |
a31f2d17 PNA |
2452 | struct mutex *cb_mutex = cfg ? cfg->cb_mutex : NULL; |
2453 | unsigned int groups; | |
1da177e4 | 2454 | |
fab2caf6 | 2455 | BUG_ON(!nl_table); |
1da177e4 | 2456 | |
6ac552fd | 2457 | if (unit < 0 || unit >= MAX_LINKS) |
1da177e4 LT |
2458 | return NULL; |
2459 | ||
2460 | if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock)) | |
2461 | return NULL; | |
2462 | ||
23fe1866 PE |
2463 | /* |
2464 | * We have to just have a reference on the net from sk, but don't | |
2465 | * get_net it. Besides, we cannot get and then put the net here. | |
2466 | * So we create one inside init_net and the move it to net. | |
2467 | */ | |
2468 | ||
2469 | if (__netlink_create(&init_net, sock, cb_mutex, unit) < 0) | |
2470 | goto out_sock_release_nosk; | |
2471 | ||
2472 | sk = sock->sk; | |
edf02087 | 2473 | sk_change_net(sk, net); |
4fdb3bb7 | 2474 | |
a31f2d17 | 2475 | if (!cfg || cfg->groups < 32) |
4277a083 | 2476 | groups = 32; |
a31f2d17 PNA |
2477 | else |
2478 | groups = cfg->groups; | |
4277a083 | 2479 | |
5c398dc8 | 2480 | listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL); |
4277a083 PM |
2481 | if (!listeners) |
2482 | goto out_sock_release; | |
2483 | ||
1da177e4 | 2484 | sk->sk_data_ready = netlink_data_ready; |
a31f2d17 PNA |
2485 | if (cfg && cfg->input) |
2486 | nlk_sk(sk)->netlink_rcv = cfg->input; | |
1da177e4 | 2487 | |
b4b51029 | 2488 | if (netlink_insert(sk, net, 0)) |
77247bbb | 2489 | goto out_sock_release; |
4fdb3bb7 | 2490 | |
77247bbb PM |
2491 | nlk = nlk_sk(sk); |
2492 | nlk->flags |= NETLINK_KERNEL_SOCKET; | |
4fdb3bb7 | 2493 | |
4fdb3bb7 | 2494 | netlink_table_grab(); |
b4b51029 EB |
2495 | if (!nl_table[unit].registered) { |
2496 | nl_table[unit].groups = groups; | |
5c398dc8 | 2497 | rcu_assign_pointer(nl_table[unit].listeners, listeners); |
b4b51029 EB |
2498 | nl_table[unit].cb_mutex = cb_mutex; |
2499 | nl_table[unit].module = module; | |
9785e10a PNA |
2500 | if (cfg) { |
2501 | nl_table[unit].bind = cfg->bind; | |
2502 | nl_table[unit].flags = cfg->flags; | |
da12c90e G |
2503 | if (cfg->compare) |
2504 | nl_table[unit].compare = cfg->compare; | |
9785e10a | 2505 | } |
b4b51029 | 2506 | nl_table[unit].registered = 1; |
f937f1f4 JJ |
2507 | } else { |
2508 | kfree(listeners); | |
869e58f8 | 2509 | nl_table[unit].registered++; |
b4b51029 | 2510 | } |
4fdb3bb7 | 2511 | netlink_table_ungrab(); |
77247bbb PM |
2512 | return sk; |
2513 | ||
4fdb3bb7 | 2514 | out_sock_release: |
4277a083 | 2515 | kfree(listeners); |
9dfbec1f | 2516 | netlink_kernel_release(sk); |
23fe1866 PE |
2517 | return NULL; |
2518 | ||
2519 | out_sock_release_nosk: | |
4fdb3bb7 | 2520 | sock_release(sock); |
77247bbb | 2521 | return NULL; |
1da177e4 | 2522 | } |
9f00d977 | 2523 | EXPORT_SYMBOL(__netlink_kernel_create); |
b7c6ba6e DL |
2524 | |
2525 | void | |
2526 | netlink_kernel_release(struct sock *sk) | |
2527 | { | |
edf02087 | 2528 | sk_release_kernel(sk); |
b7c6ba6e DL |
2529 | } |
2530 | EXPORT_SYMBOL(netlink_kernel_release); | |
2531 | ||
d136f1bd | 2532 | int __netlink_change_ngroups(struct sock *sk, unsigned int groups) |
b4ff4f04 | 2533 | { |
5c398dc8 | 2534 | struct listeners *new, *old; |
b4ff4f04 | 2535 | struct netlink_table *tbl = &nl_table[sk->sk_protocol]; |
b4ff4f04 JB |
2536 | |
2537 | if (groups < 32) | |
2538 | groups = 32; | |
2539 | ||
b4ff4f04 | 2540 | if (NLGRPSZ(tbl->groups) < NLGRPSZ(groups)) { |
5c398dc8 ED |
2541 | new = kzalloc(sizeof(*new) + NLGRPSZ(groups), GFP_ATOMIC); |
2542 | if (!new) | |
d136f1bd | 2543 | return -ENOMEM; |
6d772ac5 | 2544 | old = nl_deref_protected(tbl->listeners); |
5c398dc8 ED |
2545 | memcpy(new->masks, old->masks, NLGRPSZ(tbl->groups)); |
2546 | rcu_assign_pointer(tbl->listeners, new); | |
2547 | ||
37b6b935 | 2548 | kfree_rcu(old, rcu); |
b4ff4f04 JB |
2549 | } |
2550 | tbl->groups = groups; | |
2551 | ||
d136f1bd JB |
2552 | return 0; |
2553 | } | |
2554 | ||
2555 | /** | |
2556 | * netlink_change_ngroups - change number of multicast groups | |
2557 | * | |
2558 | * This changes the number of multicast groups that are available | |
2559 | * on a certain netlink family. Note that it is not possible to | |
2560 | * change the number of groups to below 32. Also note that it does | |
2561 | * not implicitly call netlink_clear_multicast_users() when the | |
2562 | * number of groups is reduced. | |
2563 | * | |
2564 | * @sk: The kernel netlink socket, as returned by netlink_kernel_create(). | |
2565 | * @groups: The new number of groups. | |
2566 | */ | |
2567 | int netlink_change_ngroups(struct sock *sk, unsigned int groups) | |
2568 | { | |
2569 | int err; | |
2570 | ||
2571 | netlink_table_grab(); | |
2572 | err = __netlink_change_ngroups(sk, groups); | |
b4ff4f04 | 2573 | netlink_table_ungrab(); |
d136f1bd | 2574 | |
b4ff4f04 JB |
2575 | return err; |
2576 | } | |
b4ff4f04 | 2577 | |
b8273570 JB |
2578 | void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group) |
2579 | { | |
2580 | struct sock *sk; | |
b8273570 JB |
2581 | struct netlink_table *tbl = &nl_table[ksk->sk_protocol]; |
2582 | ||
b67bfe0d | 2583 | sk_for_each_bound(sk, &tbl->mc_list) |
b8273570 JB |
2584 | netlink_update_socket_mc(nlk_sk(sk), group, 0); |
2585 | } | |
2586 | ||
a46621a3 | 2587 | struct nlmsghdr * |
15e47304 | 2588 | __nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags) |
a46621a3 DV |
2589 | { |
2590 | struct nlmsghdr *nlh; | |
573ce260 | 2591 | int size = nlmsg_msg_size(len); |
a46621a3 | 2592 | |
23b45672 | 2593 | nlh = (struct nlmsghdr *)skb_put(skb, NLMSG_ALIGN(size)); |
a46621a3 DV |
2594 | nlh->nlmsg_type = type; |
2595 | nlh->nlmsg_len = size; | |
2596 | nlh->nlmsg_flags = flags; | |
15e47304 | 2597 | nlh->nlmsg_pid = portid; |
a46621a3 DV |
2598 | nlh->nlmsg_seq = seq; |
2599 | if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0) | |
573ce260 | 2600 | memset(nlmsg_data(nlh) + len, 0, NLMSG_ALIGN(size) - size); |
a46621a3 DV |
2601 | return nlh; |
2602 | } | |
2603 | EXPORT_SYMBOL(__nlmsg_put); | |
2604 | ||
1da177e4 LT |
2605 | /* |
2606 | * It looks a bit ugly. | |
2607 | * It would be better to create kernel thread. | |
2608 | */ | |
2609 | ||
2610 | static int netlink_dump(struct sock *sk) | |
2611 | { | |
2612 | struct netlink_sock *nlk = nlk_sk(sk); | |
2613 | struct netlink_callback *cb; | |
c7ac8679 | 2614 | struct sk_buff *skb = NULL; |
1da177e4 | 2615 | struct nlmsghdr *nlh; |
bf8b79e4 | 2616 | int len, err = -ENOBUFS; |
c7ac8679 | 2617 | int alloc_size; |
1da177e4 | 2618 | |
af65bdfc | 2619 | mutex_lock(nlk->cb_mutex); |
16b304f3 | 2620 | if (!nlk->cb_running) { |
bf8b79e4 TG |
2621 | err = -EINVAL; |
2622 | goto errout_skb; | |
1da177e4 LT |
2623 | } |
2624 | ||
16b304f3 | 2625 | cb = &nlk->cb; |
c7ac8679 GR |
2626 | alloc_size = max_t(int, cb->min_dump_alloc, NLMSG_GOODSIZE); |
2627 | ||
f9c22888 PM |
2628 | if (!netlink_rx_is_mmaped(sk) && |
2629 | atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) | |
2630 | goto errout_skb; | |
9063e21f ED |
2631 | |
2632 | /* NLMSG_GOODSIZE is small to avoid high order allocations being | |
2633 | * required, but it makes sense to _attempt_ a 16K bytes allocation | |
2634 | * to reduce number of system calls on dump operations, if user | |
2635 | * ever provided a big enough buffer. | |
2636 | */ | |
2637 | if (alloc_size < nlk->max_recvmsg_len) { | |
2638 | skb = netlink_alloc_skb(sk, | |
2639 | nlk->max_recvmsg_len, | |
2640 | nlk->portid, | |
2641 | GFP_KERNEL | | |
2642 | __GFP_NOWARN | | |
2643 | __GFP_NORETRY); | |
2644 | /* available room should be exact amount to avoid MSG_TRUNC */ | |
2645 | if (skb) | |
2646 | skb_reserve(skb, skb_tailroom(skb) - | |
2647 | nlk->max_recvmsg_len); | |
2648 | } | |
2649 | if (!skb) | |
2650 | skb = netlink_alloc_skb(sk, alloc_size, nlk->portid, | |
2651 | GFP_KERNEL); | |
c7ac8679 | 2652 | if (!skb) |
c63d6ea3 | 2653 | goto errout_skb; |
f9c22888 | 2654 | netlink_skb_set_owner_r(skb, sk); |
c7ac8679 | 2655 | |
1da177e4 LT |
2656 | len = cb->dump(skb, cb); |
2657 | ||
2658 | if (len > 0) { | |
af65bdfc | 2659 | mutex_unlock(nlk->cb_mutex); |
b1153f29 SH |
2660 | |
2661 | if (sk_filter(sk, skb)) | |
2662 | kfree_skb(skb); | |
4a7e7c2a ED |
2663 | else |
2664 | __netlink_sendskb(sk, skb); | |
1da177e4 LT |
2665 | return 0; |
2666 | } | |
2667 | ||
bf8b79e4 TG |
2668 | nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(len), NLM_F_MULTI); |
2669 | if (!nlh) | |
2670 | goto errout_skb; | |
2671 | ||
670dc283 JB |
2672 | nl_dump_check_consistent(cb, nlh); |
2673 | ||
bf8b79e4 TG |
2674 | memcpy(nlmsg_data(nlh), &len, sizeof(len)); |
2675 | ||
b1153f29 SH |
2676 | if (sk_filter(sk, skb)) |
2677 | kfree_skb(skb); | |
4a7e7c2a ED |
2678 | else |
2679 | __netlink_sendskb(sk, skb); | |
1da177e4 | 2680 | |
a8f74b22 TG |
2681 | if (cb->done) |
2682 | cb->done(cb); | |
1da177e4 | 2683 | |
16b304f3 PS |
2684 | nlk->cb_running = false; |
2685 | mutex_unlock(nlk->cb_mutex); | |
6dc878a8 | 2686 | module_put(cb->module); |
16b304f3 | 2687 | consume_skb(cb->skb); |
1da177e4 | 2688 | return 0; |
1797754e | 2689 | |
bf8b79e4 | 2690 | errout_skb: |
af65bdfc | 2691 | mutex_unlock(nlk->cb_mutex); |
bf8b79e4 | 2692 | kfree_skb(skb); |
bf8b79e4 | 2693 | return err; |
1da177e4 LT |
2694 | } |
2695 | ||
6dc878a8 G |
2696 | int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb, |
2697 | const struct nlmsghdr *nlh, | |
2698 | struct netlink_dump_control *control) | |
1da177e4 LT |
2699 | { |
2700 | struct netlink_callback *cb; | |
2701 | struct sock *sk; | |
2702 | struct netlink_sock *nlk; | |
b44d211e | 2703 | int ret; |
1da177e4 | 2704 | |
f9c22888 PM |
2705 | /* Memory mapped dump requests need to be copied to avoid looping |
2706 | * on the pending state in netlink_mmap_sendmsg() while the CB hold | |
2707 | * a reference to the skb. | |
2708 | */ | |
2709 | if (netlink_skb_is_mmaped(skb)) { | |
2710 | skb = skb_copy(skb, GFP_KERNEL); | |
16b304f3 | 2711 | if (skb == NULL) |
f9c22888 | 2712 | return -ENOBUFS; |
f9c22888 PM |
2713 | } else |
2714 | atomic_inc(&skb->users); | |
2715 | ||
15e47304 | 2716 | sk = netlink_lookup(sock_net(ssk), ssk->sk_protocol, NETLINK_CB(skb).portid); |
1da177e4 | 2717 | if (sk == NULL) { |
16b304f3 PS |
2718 | ret = -ECONNREFUSED; |
2719 | goto error_free; | |
1da177e4 | 2720 | } |
6dc878a8 | 2721 | |
16b304f3 | 2722 | nlk = nlk_sk(sk); |
af65bdfc | 2723 | mutex_lock(nlk->cb_mutex); |
6dc878a8 | 2724 | /* A dump is in progress... */ |
16b304f3 | 2725 | if (nlk->cb_running) { |
6dc878a8 | 2726 | ret = -EBUSY; |
16b304f3 | 2727 | goto error_unlock; |
1da177e4 | 2728 | } |
6dc878a8 | 2729 | /* add reference of module which cb->dump belongs to */ |
16b304f3 | 2730 | if (!try_module_get(control->module)) { |
6dc878a8 | 2731 | ret = -EPROTONOSUPPORT; |
16b304f3 | 2732 | goto error_unlock; |
6dc878a8 G |
2733 | } |
2734 | ||
16b304f3 PS |
2735 | cb = &nlk->cb; |
2736 | memset(cb, 0, sizeof(*cb)); | |
2737 | cb->dump = control->dump; | |
2738 | cb->done = control->done; | |
2739 | cb->nlh = nlh; | |
2740 | cb->data = control->data; | |
2741 | cb->module = control->module; | |
2742 | cb->min_dump_alloc = control->min_dump_alloc; | |
2743 | cb->skb = skb; | |
2744 | ||
2745 | nlk->cb_running = true; | |
2746 | ||
af65bdfc | 2747 | mutex_unlock(nlk->cb_mutex); |
1da177e4 | 2748 | |
b44d211e | 2749 | ret = netlink_dump(sk); |
1da177e4 | 2750 | sock_put(sk); |
5c58298c | 2751 | |
b44d211e AV |
2752 | if (ret) |
2753 | return ret; | |
2754 | ||
5c58298c DL |
2755 | /* We successfully started a dump, by returning -EINTR we |
2756 | * signal not to send ACK even if it was requested. | |
2757 | */ | |
2758 | return -EINTR; | |
16b304f3 PS |
2759 | |
2760 | error_unlock: | |
2761 | sock_put(sk); | |
2762 | mutex_unlock(nlk->cb_mutex); | |
2763 | error_free: | |
2764 | kfree_skb(skb); | |
2765 | return ret; | |
1da177e4 | 2766 | } |
6dc878a8 | 2767 | EXPORT_SYMBOL(__netlink_dump_start); |
1da177e4 LT |
2768 | |
2769 | void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err) | |
2770 | { | |
2771 | struct sk_buff *skb; | |
2772 | struct nlmsghdr *rep; | |
2773 | struct nlmsgerr *errmsg; | |
339bf98f | 2774 | size_t payload = sizeof(*errmsg); |
1da177e4 | 2775 | |
339bf98f TG |
2776 | /* error messages get the original request appened */ |
2777 | if (err) | |
2778 | payload += nlmsg_len(nlh); | |
1da177e4 | 2779 | |
f9c22888 PM |
2780 | skb = netlink_alloc_skb(in_skb->sk, nlmsg_total_size(payload), |
2781 | NETLINK_CB(in_skb).portid, GFP_KERNEL); | |
1da177e4 LT |
2782 | if (!skb) { |
2783 | struct sock *sk; | |
2784 | ||
3b1e0a65 | 2785 | sk = netlink_lookup(sock_net(in_skb->sk), |
b4b51029 | 2786 | in_skb->sk->sk_protocol, |
15e47304 | 2787 | NETLINK_CB(in_skb).portid); |
1da177e4 LT |
2788 | if (sk) { |
2789 | sk->sk_err = ENOBUFS; | |
2790 | sk->sk_error_report(sk); | |
2791 | sock_put(sk); | |
2792 | } | |
2793 | return; | |
2794 | } | |
2795 | ||
15e47304 | 2796 | rep = __nlmsg_put(skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, |
5dba93ae | 2797 | NLMSG_ERROR, payload, 0); |
bf8b79e4 | 2798 | errmsg = nlmsg_data(rep); |
1da177e4 | 2799 | errmsg->error = err; |
bf8b79e4 | 2800 | memcpy(&errmsg->msg, nlh, err ? nlh->nlmsg_len : sizeof(*nlh)); |
15e47304 | 2801 | netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).portid, MSG_DONTWAIT); |
1da177e4 | 2802 | } |
6ac552fd | 2803 | EXPORT_SYMBOL(netlink_ack); |
1da177e4 | 2804 | |
cd40b7d3 | 2805 | int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *, |
1d00a4eb | 2806 | struct nlmsghdr *)) |
82ace47a | 2807 | { |
82ace47a TG |
2808 | struct nlmsghdr *nlh; |
2809 | int err; | |
2810 | ||
2811 | while (skb->len >= nlmsg_total_size(0)) { | |
cd40b7d3 DL |
2812 | int msglen; |
2813 | ||
b529ccf2 | 2814 | nlh = nlmsg_hdr(skb); |
d35b6856 | 2815 | err = 0; |
82ace47a | 2816 | |
ad8e4b75 | 2817 | if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len) |
82ace47a TG |
2818 | return 0; |
2819 | ||
d35b6856 TG |
2820 | /* Only requests are handled by the kernel */ |
2821 | if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) | |
5c58298c | 2822 | goto ack; |
45e7ae7f TG |
2823 | |
2824 | /* Skip control messages */ | |
2825 | if (nlh->nlmsg_type < NLMSG_MIN_TYPE) | |
5c58298c | 2826 | goto ack; |
d35b6856 | 2827 | |
1d00a4eb | 2828 | err = cb(skb, nlh); |
5c58298c DL |
2829 | if (err == -EINTR) |
2830 | goto skip; | |
2831 | ||
2832 | ack: | |
d35b6856 | 2833 | if (nlh->nlmsg_flags & NLM_F_ACK || err) |
82ace47a | 2834 | netlink_ack(skb, nlh, err); |
82ace47a | 2835 | |
5c58298c | 2836 | skip: |
6ac552fd | 2837 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
cd40b7d3 DL |
2838 | if (msglen > skb->len) |
2839 | msglen = skb->len; | |
2840 | skb_pull(skb, msglen); | |
82ace47a TG |
2841 | } |
2842 | ||
2843 | return 0; | |
2844 | } | |
6ac552fd | 2845 | EXPORT_SYMBOL(netlink_rcv_skb); |
82ace47a | 2846 | |
d387f6ad TG |
2847 | /** |
2848 | * nlmsg_notify - send a notification netlink message | |
2849 | * @sk: netlink socket to use | |
2850 | * @skb: notification message | |
15e47304 | 2851 | * @portid: destination netlink portid for reports or 0 |
d387f6ad TG |
2852 | * @group: destination multicast group or 0 |
2853 | * @report: 1 to report back, 0 to disable | |
2854 | * @flags: allocation flags | |
2855 | */ | |
15e47304 | 2856 | int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid, |
d387f6ad TG |
2857 | unsigned int group, int report, gfp_t flags) |
2858 | { | |
2859 | int err = 0; | |
2860 | ||
2861 | if (group) { | |
15e47304 | 2862 | int exclude_portid = 0; |
d387f6ad TG |
2863 | |
2864 | if (report) { | |
2865 | atomic_inc(&skb->users); | |
15e47304 | 2866 | exclude_portid = portid; |
d387f6ad TG |
2867 | } |
2868 | ||
1ce85fe4 PNA |
2869 | /* errors reported via destination sk->sk_err, but propagate |
2870 | * delivery errors if NETLINK_BROADCAST_ERROR flag is set */ | |
15e47304 | 2871 | err = nlmsg_multicast(sk, skb, exclude_portid, group, flags); |
d387f6ad TG |
2872 | } |
2873 | ||
1ce85fe4 PNA |
2874 | if (report) { |
2875 | int err2; | |
2876 | ||
15e47304 | 2877 | err2 = nlmsg_unicast(sk, skb, portid); |
1ce85fe4 PNA |
2878 | if (!err || err == -ESRCH) |
2879 | err = err2; | |
2880 | } | |
d387f6ad TG |
2881 | |
2882 | return err; | |
2883 | } | |
6ac552fd | 2884 | EXPORT_SYMBOL(nlmsg_notify); |
d387f6ad | 2885 | |
1da177e4 LT |
2886 | #ifdef CONFIG_PROC_FS |
2887 | struct nl_seq_iter { | |
e372c414 | 2888 | struct seq_net_private p; |
1da177e4 LT |
2889 | int link; |
2890 | int hash_idx; | |
2891 | }; | |
2892 | ||
2893 | static struct sock *netlink_seq_socket_idx(struct seq_file *seq, loff_t pos) | |
2894 | { | |
2895 | struct nl_seq_iter *iter = seq->private; | |
2896 | int i, j; | |
e341694e | 2897 | struct netlink_sock *nlk; |
1da177e4 | 2898 | struct sock *s; |
1da177e4 LT |
2899 | loff_t off = 0; |
2900 | ||
6ac552fd | 2901 | for (i = 0; i < MAX_LINKS; i++) { |
e341694e | 2902 | struct rhashtable *ht = &nl_table[i].hash; |
67a24ac1 | 2903 | const struct bucket_table *tbl = rht_dereference_rcu(ht->tbl, ht); |
e341694e TG |
2904 | |
2905 | for (j = 0; j < tbl->size; j++) { | |
2906 | rht_for_each_entry_rcu(nlk, tbl->buckets[j], node) { | |
2907 | s = (struct sock *)nlk; | |
1da177e4 | 2908 | |
1218854a | 2909 | if (sock_net(s) != seq_file_net(seq)) |
b4b51029 | 2910 | continue; |
1da177e4 LT |
2911 | if (off == pos) { |
2912 | iter->link = i; | |
2913 | iter->hash_idx = j; | |
2914 | return s; | |
2915 | } | |
2916 | ++off; | |
2917 | } | |
2918 | } | |
2919 | } | |
2920 | return NULL; | |
2921 | } | |
2922 | ||
2923 | static void *netlink_seq_start(struct seq_file *seq, loff_t *pos) | |
9ce12eb1 | 2924 | __acquires(RCU) |
1da177e4 | 2925 | { |
e341694e | 2926 | rcu_read_lock(); |
1da177e4 LT |
2927 | return *pos ? netlink_seq_socket_idx(seq, *pos - 1) : SEQ_START_TOKEN; |
2928 | } | |
2929 | ||
2930 | static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
2931 | { | |
e341694e | 2932 | struct netlink_sock *nlk; |
1da177e4 | 2933 | struct nl_seq_iter *iter; |
da12c90e | 2934 | struct net *net; |
1da177e4 LT |
2935 | int i, j; |
2936 | ||
2937 | ++*pos; | |
2938 | ||
2939 | if (v == SEQ_START_TOKEN) | |
2940 | return netlink_seq_socket_idx(seq, 0); | |
746fac4d | 2941 | |
da12c90e | 2942 | net = seq_file_net(seq); |
b4b51029 | 2943 | iter = seq->private; |
e341694e TG |
2944 | nlk = v; |
2945 | ||
2946 | rht_for_each_entry_rcu(nlk, nlk->node.next, node) | |
2947 | if (net_eq(sock_net((struct sock *)nlk), net)) | |
2948 | return nlk; | |
1da177e4 | 2949 | |
1da177e4 LT |
2950 | i = iter->link; |
2951 | j = iter->hash_idx + 1; | |
2952 | ||
2953 | do { | |
e341694e | 2954 | struct rhashtable *ht = &nl_table[i].hash; |
67a24ac1 | 2955 | const struct bucket_table *tbl = rht_dereference_rcu(ht->tbl, ht); |
da12c90e | 2956 | |
e341694e TG |
2957 | for (; j < tbl->size; j++) { |
2958 | rht_for_each_entry_rcu(nlk, tbl->buckets[j], node) { | |
2959 | if (net_eq(sock_net((struct sock *)nlk), net)) { | |
2960 | iter->link = i; | |
2961 | iter->hash_idx = j; | |
2962 | return nlk; | |
2963 | } | |
1da177e4 LT |
2964 | } |
2965 | } | |
2966 | ||
2967 | j = 0; | |
2968 | } while (++i < MAX_LINKS); | |
2969 | ||
2970 | return NULL; | |
2971 | } | |
2972 | ||
2973 | static void netlink_seq_stop(struct seq_file *seq, void *v) | |
9ce12eb1 | 2974 | __releases(RCU) |
1da177e4 | 2975 | { |
e341694e | 2976 | rcu_read_unlock(); |
1da177e4 LT |
2977 | } |
2978 | ||
2979 | ||
2980 | static int netlink_seq_show(struct seq_file *seq, void *v) | |
2981 | { | |
658cb354 | 2982 | if (v == SEQ_START_TOKEN) { |
1da177e4 LT |
2983 | seq_puts(seq, |
2984 | "sk Eth Pid Groups " | |
cf0aa4e0 | 2985 | "Rmem Wmem Dump Locks Drops Inode\n"); |
658cb354 | 2986 | } else { |
1da177e4 LT |
2987 | struct sock *s = v; |
2988 | struct netlink_sock *nlk = nlk_sk(s); | |
2989 | ||
16b304f3 | 2990 | seq_printf(seq, "%pK %-3d %-6u %08x %-8d %-8d %d %-8d %-8d %-8lu\n", |
1da177e4 LT |
2991 | s, |
2992 | s->sk_protocol, | |
15e47304 | 2993 | nlk->portid, |
513c2500 | 2994 | nlk->groups ? (u32)nlk->groups[0] : 0, |
31e6d363 ED |
2995 | sk_rmem_alloc_get(s), |
2996 | sk_wmem_alloc_get(s), | |
16b304f3 | 2997 | nlk->cb_running, |
38938bfe | 2998 | atomic_read(&s->sk_refcnt), |
cf0aa4e0 MY |
2999 | atomic_read(&s->sk_drops), |
3000 | sock_i_ino(s) | |
1da177e4 LT |
3001 | ); |
3002 | ||
3003 | } | |
3004 | return 0; | |
3005 | } | |
3006 | ||
56b3d975 | 3007 | static const struct seq_operations netlink_seq_ops = { |
1da177e4 LT |
3008 | .start = netlink_seq_start, |
3009 | .next = netlink_seq_next, | |
3010 | .stop = netlink_seq_stop, | |
3011 | .show = netlink_seq_show, | |
3012 | }; | |
3013 | ||
3014 | ||
3015 | static int netlink_seq_open(struct inode *inode, struct file *file) | |
3016 | { | |
e372c414 DL |
3017 | return seq_open_net(inode, file, &netlink_seq_ops, |
3018 | sizeof(struct nl_seq_iter)); | |
b4b51029 EB |
3019 | } |
3020 | ||
da7071d7 | 3021 | static const struct file_operations netlink_seq_fops = { |
1da177e4 LT |
3022 | .owner = THIS_MODULE, |
3023 | .open = netlink_seq_open, | |
3024 | .read = seq_read, | |
3025 | .llseek = seq_lseek, | |
e372c414 | 3026 | .release = seq_release_net, |
1da177e4 LT |
3027 | }; |
3028 | ||
3029 | #endif | |
3030 | ||
3031 | int netlink_register_notifier(struct notifier_block *nb) | |
3032 | { | |
e041c683 | 3033 | return atomic_notifier_chain_register(&netlink_chain, nb); |
1da177e4 | 3034 | } |
6ac552fd | 3035 | EXPORT_SYMBOL(netlink_register_notifier); |
1da177e4 LT |
3036 | |
3037 | int netlink_unregister_notifier(struct notifier_block *nb) | |
3038 | { | |
e041c683 | 3039 | return atomic_notifier_chain_unregister(&netlink_chain, nb); |
1da177e4 | 3040 | } |
6ac552fd | 3041 | EXPORT_SYMBOL(netlink_unregister_notifier); |
746fac4d | 3042 | |
90ddc4f0 | 3043 | static const struct proto_ops netlink_ops = { |
1da177e4 LT |
3044 | .family = PF_NETLINK, |
3045 | .owner = THIS_MODULE, | |
3046 | .release = netlink_release, | |
3047 | .bind = netlink_bind, | |
3048 | .connect = netlink_connect, | |
3049 | .socketpair = sock_no_socketpair, | |
3050 | .accept = sock_no_accept, | |
3051 | .getname = netlink_getname, | |
9652e931 | 3052 | .poll = netlink_poll, |
1da177e4 LT |
3053 | .ioctl = sock_no_ioctl, |
3054 | .listen = sock_no_listen, | |
3055 | .shutdown = sock_no_shutdown, | |
9a4595bc PM |
3056 | .setsockopt = netlink_setsockopt, |
3057 | .getsockopt = netlink_getsockopt, | |
1da177e4 LT |
3058 | .sendmsg = netlink_sendmsg, |
3059 | .recvmsg = netlink_recvmsg, | |
ccdfcc39 | 3060 | .mmap = netlink_mmap, |
1da177e4 LT |
3061 | .sendpage = sock_no_sendpage, |
3062 | }; | |
3063 | ||
ec1b4cf7 | 3064 | static const struct net_proto_family netlink_family_ops = { |
1da177e4 LT |
3065 | .family = PF_NETLINK, |
3066 | .create = netlink_create, | |
3067 | .owner = THIS_MODULE, /* for consistency 8) */ | |
3068 | }; | |
3069 | ||
4665079c | 3070 | static int __net_init netlink_net_init(struct net *net) |
b4b51029 EB |
3071 | { |
3072 | #ifdef CONFIG_PROC_FS | |
d4beaa66 | 3073 | if (!proc_create("netlink", 0, net->proc_net, &netlink_seq_fops)) |
b4b51029 EB |
3074 | return -ENOMEM; |
3075 | #endif | |
3076 | return 0; | |
3077 | } | |
3078 | ||
4665079c | 3079 | static void __net_exit netlink_net_exit(struct net *net) |
b4b51029 EB |
3080 | { |
3081 | #ifdef CONFIG_PROC_FS | |
ece31ffd | 3082 | remove_proc_entry("netlink", net->proc_net); |
b4b51029 EB |
3083 | #endif |
3084 | } | |
3085 | ||
b963ea89 DM |
3086 | static void __init netlink_add_usersock_entry(void) |
3087 | { | |
5c398dc8 | 3088 | struct listeners *listeners; |
b963ea89 DM |
3089 | int groups = 32; |
3090 | ||
5c398dc8 | 3091 | listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL); |
b963ea89 | 3092 | if (!listeners) |
5c398dc8 | 3093 | panic("netlink_add_usersock_entry: Cannot allocate listeners\n"); |
b963ea89 DM |
3094 | |
3095 | netlink_table_grab(); | |
3096 | ||
3097 | nl_table[NETLINK_USERSOCK].groups = groups; | |
5c398dc8 | 3098 | rcu_assign_pointer(nl_table[NETLINK_USERSOCK].listeners, listeners); |
b963ea89 DM |
3099 | nl_table[NETLINK_USERSOCK].module = THIS_MODULE; |
3100 | nl_table[NETLINK_USERSOCK].registered = 1; | |
9785e10a | 3101 | nl_table[NETLINK_USERSOCK].flags = NL_CFG_F_NONROOT_SEND; |
b963ea89 DM |
3102 | |
3103 | netlink_table_ungrab(); | |
3104 | } | |
3105 | ||
022cbae6 | 3106 | static struct pernet_operations __net_initdata netlink_net_ops = { |
b4b51029 EB |
3107 | .init = netlink_net_init, |
3108 | .exit = netlink_net_exit, | |
3109 | }; | |
3110 | ||
1da177e4 LT |
3111 | static int __init netlink_proto_init(void) |
3112 | { | |
1da177e4 | 3113 | int i; |
1da177e4 | 3114 | int err = proto_register(&netlink_proto, 0); |
e341694e TG |
3115 | struct rhashtable_params ht_params = { |
3116 | .head_offset = offsetof(struct netlink_sock, node), | |
3117 | .key_offset = offsetof(struct netlink_sock, portid), | |
3118 | .key_len = sizeof(u32), /* portid */ | |
3119 | .hashfn = arch_fast_hash, | |
3120 | .max_shift = 16, /* 64K */ | |
3121 | .grow_decision = rht_grow_above_75, | |
3122 | .shrink_decision = rht_shrink_below_30, | |
3123 | .mutex_is_held = lockdep_nl_sk_hash_is_held, | |
3124 | }; | |
1da177e4 LT |
3125 | |
3126 | if (err != 0) | |
3127 | goto out; | |
3128 | ||
fab25745 | 3129 | BUILD_BUG_ON(sizeof(struct netlink_skb_parms) > FIELD_SIZEOF(struct sk_buff, cb)); |
1da177e4 | 3130 | |
0da974f4 | 3131 | nl_table = kcalloc(MAX_LINKS, sizeof(*nl_table), GFP_KERNEL); |
fab2caf6 AM |
3132 | if (!nl_table) |
3133 | goto panic; | |
1da177e4 | 3134 | |
1da177e4 | 3135 | for (i = 0; i < MAX_LINKS; i++) { |
e341694e TG |
3136 | if (rhashtable_init(&nl_table[i].hash, &ht_params) < 0) { |
3137 | while (--i > 0) | |
3138 | rhashtable_destroy(&nl_table[i].hash); | |
1da177e4 | 3139 | kfree(nl_table); |
fab2caf6 | 3140 | goto panic; |
1da177e4 | 3141 | } |
1da177e4 LT |
3142 | } |
3143 | ||
bcbde0d4 DB |
3144 | INIT_LIST_HEAD(&netlink_tap_all); |
3145 | ||
b963ea89 DM |
3146 | netlink_add_usersock_entry(); |
3147 | ||
1da177e4 | 3148 | sock_register(&netlink_family_ops); |
b4b51029 | 3149 | register_pernet_subsys(&netlink_net_ops); |
746fac4d | 3150 | /* The netlink device handler may be needed early. */ |
1da177e4 LT |
3151 | rtnetlink_init(); |
3152 | out: | |
3153 | return err; | |
fab2caf6 AM |
3154 | panic: |
3155 | panic("netlink_init: Cannot allocate nl_table\n"); | |
1da177e4 LT |
3156 | } |
3157 | ||
1da177e4 | 3158 | core_initcall(netlink_proto_init); |