Commit | Line | Data |
---|---|---|
2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /* |
3 | * NETLINK Kernel-user communication protocol. | |
4 | * | |
113aa838 | 5 | * Authors: Alan Cox <alan@lxorguk.ukuu.org.uk> |
1da177e4 | 6 | * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> |
cd1df525 | 7 | * Patrick McHardy <kaber@trash.net> |
1da177e4 | 8 | * |
1da177e4 LT |
9 | * Tue Jun 26 14:36:48 MEST 2001 Herbert "herp" Rosmanith |
10 | * added netlink_proto_exit | |
11 | * Tue Jan 22 18:32:44 BRST 2002 Arnaldo C. de Melo <acme@conectiva.com.br> | |
12 | * use nlk_sk, as sk->protinfo is on a diet 8) | |
4fdb3bb7 HW |
13 | * Fri Jul 22 19:51:12 MEST 2005 Harald Welte <laforge@gnumonks.org> |
14 | * - inc module use count of module that owns | |
15 | * the kernel socket in case userspace opens | |
16 | * socket of same protocol | |
17 | * - remove all module support, since netlink is | |
18 | * mandatory if CONFIG_NET=y these days | |
1da177e4 LT |
19 | */ |
20 | ||
1da177e4 LT |
21 | #include <linux/module.h> |
22 | ||
4fc268d2 | 23 | #include <linux/capability.h> |
1da177e4 LT |
24 | #include <linux/kernel.h> |
25 | #include <linux/init.h> | |
1da177e4 LT |
26 | #include <linux/signal.h> |
27 | #include <linux/sched.h> | |
28 | #include <linux/errno.h> | |
29 | #include <linux/string.h> | |
30 | #include <linux/stat.h> | |
31 | #include <linux/socket.h> | |
32 | #include <linux/un.h> | |
33 | #include <linux/fcntl.h> | |
34 | #include <linux/termios.h> | |
35 | #include <linux/sockios.h> | |
36 | #include <linux/net.h> | |
37 | #include <linux/fs.h> | |
38 | #include <linux/slab.h> | |
7c0f6ba6 | 39 | #include <linux/uaccess.h> |
1da177e4 LT |
40 | #include <linux/skbuff.h> |
41 | #include <linux/netdevice.h> | |
42 | #include <linux/rtnetlink.h> | |
43 | #include <linux/proc_fs.h> | |
44 | #include <linux/seq_file.h> | |
1da177e4 LT |
45 | #include <linux/notifier.h> |
46 | #include <linux/security.h> | |
47 | #include <linux/jhash.h> | |
48 | #include <linux/jiffies.h> | |
49 | #include <linux/random.h> | |
50 | #include <linux/bitops.h> | |
51 | #include <linux/mm.h> | |
52 | #include <linux/types.h> | |
54e0f520 | 53 | #include <linux/audit.h> |
af65bdfc | 54 | #include <linux/mutex.h> |
ccdfcc39 | 55 | #include <linux/vmalloc.h> |
bcbde0d4 | 56 | #include <linux/if_arp.h> |
e341694e | 57 | #include <linux/rhashtable.h> |
9652e931 | 58 | #include <asm/cacheflush.h> |
e341694e | 59 | #include <linux/hash.h> |
ee1c2442 | 60 | #include <linux/genetlink.h> |
7212462f | 61 | #include <linux/net_namespace.h> |
bc5b6c0b | 62 | #include <linux/nospec.h> |
951cf368 | 63 | #include <linux/btf_ids.h> |
54e0f520 | 64 | |
457c4cbc | 65 | #include <net/net_namespace.h> |
25e3f70f | 66 | #include <net/netns/generic.h> |
1da177e4 LT |
67 | #include <net/sock.h> |
68 | #include <net/scm.h> | |
82ace47a | 69 | #include <net/netlink.h> |
1da177e4 | 70 | |
0f29c768 | 71 | #include "af_netlink.h" |
1da177e4 | 72 | |
5c398dc8 ED |
73 | struct listeners { |
74 | struct rcu_head rcu; | |
2b738124 | 75 | unsigned long masks[]; |
6c04bb18 JB |
76 | }; |
77 | ||
cd967e05 | 78 | /* state bits */ |
cc3a572f | 79 | #define NETLINK_S_CONGESTED 0x0 |
cd967e05 | 80 | |
035c4c16 | 81 | static inline int netlink_is_kernel(struct sock *sk) |
aed81560 | 82 | { |
cc3a572f | 83 | return nlk_sk(sk)->flags & NETLINK_F_KERNEL_SOCKET; |
aed81560 DL |
84 | } |
85 | ||
91dd93f9 | 86 | struct netlink_table *nl_table __read_mostly; |
0f29c768 | 87 | EXPORT_SYMBOL_GPL(nl_table); |
1da177e4 LT |
88 | |
89 | static DECLARE_WAIT_QUEUE_HEAD(nl_table_wait); | |
90 | ||
8a0f5ccf HX |
91 | static struct lock_class_key nlk_cb_mutex_keys[MAX_LINKS]; |
92 | ||
93 | static const char *const nlk_cb_mutex_key_strings[MAX_LINKS + 1] = { | |
94 | "nlk_cb_mutex-ROUTE", | |
95 | "nlk_cb_mutex-1", | |
96 | "nlk_cb_mutex-USERSOCK", | |
97 | "nlk_cb_mutex-FIREWALL", | |
98 | "nlk_cb_mutex-SOCK_DIAG", | |
99 | "nlk_cb_mutex-NFLOG", | |
100 | "nlk_cb_mutex-XFRM", | |
101 | "nlk_cb_mutex-SELINUX", | |
102 | "nlk_cb_mutex-ISCSI", | |
103 | "nlk_cb_mutex-AUDIT", | |
104 | "nlk_cb_mutex-FIB_LOOKUP", | |
105 | "nlk_cb_mutex-CONNECTOR", | |
106 | "nlk_cb_mutex-NETFILTER", | |
107 | "nlk_cb_mutex-IP6_FW", | |
108 | "nlk_cb_mutex-DNRTMSG", | |
109 | "nlk_cb_mutex-KOBJECT_UEVENT", | |
110 | "nlk_cb_mutex-GENERIC", | |
111 | "nlk_cb_mutex-17", | |
112 | "nlk_cb_mutex-SCSITRANSPORT", | |
113 | "nlk_cb_mutex-ECRYPTFS", | |
114 | "nlk_cb_mutex-RDMA", | |
115 | "nlk_cb_mutex-CRYPTO", | |
116 | "nlk_cb_mutex-SMC", | |
117 | "nlk_cb_mutex-23", | |
118 | "nlk_cb_mutex-24", | |
119 | "nlk_cb_mutex-25", | |
120 | "nlk_cb_mutex-26", | |
121 | "nlk_cb_mutex-27", | |
122 | "nlk_cb_mutex-28", | |
123 | "nlk_cb_mutex-29", | |
124 | "nlk_cb_mutex-30", | |
125 | "nlk_cb_mutex-31", | |
126 | "nlk_cb_mutex-MAX_LINKS" | |
127 | }; | |
128 | ||
1da177e4 | 129 | static int netlink_dump(struct sock *sk); |
1da177e4 | 130 | |
78fd1d0a | 131 | /* nl_table locking explained: |
21e4902a | 132 | * Lookup and traversal are protected with an RCU read-side lock. Insertion |
c5adde94 | 133 | * and removal are protected with per bucket lock while using RCU list |
21e4902a TG |
134 | * modification primitives and may run in parallel to RCU protected lookups. |
135 | * Destruction of the Netlink socket may only occur *after* nl_table_lock has | |
136 | * been acquired * either during or after the socket has been removed from | |
137 | * the list and after an RCU grace period. | |
78fd1d0a | 138 | */ |
0f29c768 AV |
139 | DEFINE_RWLOCK(nl_table_lock); |
140 | EXPORT_SYMBOL_GPL(nl_table_lock); | |
1da177e4 LT |
141 | static atomic_t nl_table_users = ATOMIC_INIT(0); |
142 | ||
6d772ac5 ED |
143 | #define nl_deref_protected(X) rcu_dereference_protected(X, lockdep_is_held(&nl_table_lock)); |
144 | ||
efa172f4 | 145 | static BLOCKING_NOTIFIER_HEAD(netlink_chain); |
1da177e4 | 146 | |
bcbde0d4 | 147 | |
c428ecd1 HX |
148 | static const struct rhashtable_params netlink_rhashtable_params; |
149 | ||
b57ef81f | 150 | static inline u32 netlink_group_mask(u32 group) |
d629b836 PM |
151 | { |
152 | return group ? 1 << (group - 1) : 0; | |
153 | } | |
154 | ||
1853c949 DB |
155 | static struct sk_buff *netlink_to_full_skb(const struct sk_buff *skb, |
156 | gfp_t gfp_mask) | |
157 | { | |
158 | unsigned int len = skb_end_offset(skb); | |
159 | struct sk_buff *new; | |
160 | ||
161 | new = alloc_skb(len, gfp_mask); | |
162 | if (new == NULL) | |
163 | return NULL; | |
164 | ||
165 | NETLINK_CB(new).portid = NETLINK_CB(skb).portid; | |
166 | NETLINK_CB(new).dst_group = NETLINK_CB(skb).dst_group; | |
167 | NETLINK_CB(new).creds = NETLINK_CB(skb).creds; | |
168 | ||
59ae1d12 | 169 | skb_put_data(new, skb->data, len); |
1853c949 DB |
170 | return new; |
171 | } | |
172 | ||
25e3f70f CW |
173 | static unsigned int netlink_tap_net_id; |
174 | ||
175 | struct netlink_tap_net { | |
176 | struct list_head netlink_tap_all; | |
b1042d35 | 177 | struct mutex netlink_tap_lock; |
25e3f70f CW |
178 | }; |
179 | ||
bcbde0d4 DB |
180 | int netlink_add_tap(struct netlink_tap *nt) |
181 | { | |
25e3f70f CW |
182 | struct net *net = dev_net(nt->dev); |
183 | struct netlink_tap_net *nn = net_generic(net, netlink_tap_net_id); | |
184 | ||
bcbde0d4 DB |
185 | if (unlikely(nt->dev->type != ARPHRD_NETLINK)) |
186 | return -EINVAL; | |
187 | ||
b1042d35 | 188 | mutex_lock(&nn->netlink_tap_lock); |
25e3f70f | 189 | list_add_rcu(&nt->list, &nn->netlink_tap_all); |
b1042d35 | 190 | mutex_unlock(&nn->netlink_tap_lock); |
bcbde0d4 | 191 | |
fcd4d35e | 192 | __module_get(nt->module); |
bcbde0d4 DB |
193 | |
194 | return 0; | |
195 | } | |
196 | EXPORT_SYMBOL_GPL(netlink_add_tap); | |
197 | ||
2173f8d9 | 198 | static int __netlink_remove_tap(struct netlink_tap *nt) |
bcbde0d4 | 199 | { |
25e3f70f CW |
200 | struct net *net = dev_net(nt->dev); |
201 | struct netlink_tap_net *nn = net_generic(net, netlink_tap_net_id); | |
bcbde0d4 DB |
202 | bool found = false; |
203 | struct netlink_tap *tmp; | |
204 | ||
b1042d35 | 205 | mutex_lock(&nn->netlink_tap_lock); |
bcbde0d4 | 206 | |
25e3f70f | 207 | list_for_each_entry(tmp, &nn->netlink_tap_all, list) { |
bcbde0d4 DB |
208 | if (nt == tmp) { |
209 | list_del_rcu(&nt->list); | |
210 | found = true; | |
211 | goto out; | |
212 | } | |
213 | } | |
214 | ||
215 | pr_warn("__netlink_remove_tap: %p not found\n", nt); | |
216 | out: | |
b1042d35 | 217 | mutex_unlock(&nn->netlink_tap_lock); |
bcbde0d4 | 218 | |
92b80eb3 | 219 | if (found) |
bcbde0d4 DB |
220 | module_put(nt->module); |
221 | ||
222 | return found ? 0 : -ENODEV; | |
223 | } | |
bcbde0d4 DB |
224 | |
225 | int netlink_remove_tap(struct netlink_tap *nt) | |
226 | { | |
227 | int ret; | |
228 | ||
229 | ret = __netlink_remove_tap(nt); | |
230 | synchronize_net(); | |
231 | ||
232 | return ret; | |
233 | } | |
234 | EXPORT_SYMBOL_GPL(netlink_remove_tap); | |
235 | ||
25e3f70f CW |
236 | static __net_init int netlink_tap_init_net(struct net *net) |
237 | { | |
238 | struct netlink_tap_net *nn = net_generic(net, netlink_tap_net_id); | |
239 | ||
240 | INIT_LIST_HEAD(&nn->netlink_tap_all); | |
b1042d35 | 241 | mutex_init(&nn->netlink_tap_lock); |
25e3f70f CW |
242 | return 0; |
243 | } | |
244 | ||
25e3f70f CW |
245 | static struct pernet_operations netlink_tap_net_ops = { |
246 | .init = netlink_tap_init_net, | |
25e3f70f CW |
247 | .id = &netlink_tap_net_id, |
248 | .size = sizeof(struct netlink_tap_net), | |
249 | }; | |
250 | ||
5ffd5cdd DB |
251 | static bool netlink_filter_tap(const struct sk_buff *skb) |
252 | { | |
253 | struct sock *sk = skb->sk; | |
5ffd5cdd DB |
254 | |
255 | /* We take the more conservative approach and | |
256 | * whitelist socket protocols that may pass. | |
257 | */ | |
258 | switch (sk->sk_protocol) { | |
259 | case NETLINK_ROUTE: | |
260 | case NETLINK_USERSOCK: | |
261 | case NETLINK_SOCK_DIAG: | |
262 | case NETLINK_NFLOG: | |
263 | case NETLINK_XFRM: | |
264 | case NETLINK_FIB_LOOKUP: | |
265 | case NETLINK_NETFILTER: | |
266 | case NETLINK_GENERIC: | |
498044bb | 267 | return true; |
5ffd5cdd DB |
268 | } |
269 | ||
498044bb | 270 | return false; |
5ffd5cdd DB |
271 | } |
272 | ||
bcbde0d4 DB |
273 | static int __netlink_deliver_tap_skb(struct sk_buff *skb, |
274 | struct net_device *dev) | |
275 | { | |
276 | struct sk_buff *nskb; | |
5ffd5cdd | 277 | struct sock *sk = skb->sk; |
bcbde0d4 DB |
278 | int ret = -ENOMEM; |
279 | ||
93c64764 KC |
280 | if (!net_eq(dev_net(dev), sock_net(sk))) |
281 | return 0; | |
282 | ||
bcbde0d4 | 283 | dev_hold(dev); |
1853c949 | 284 | |
d1b4c689 | 285 | if (is_vmalloc_addr(skb->head)) |
1853c949 DB |
286 | nskb = netlink_to_full_skb(skb, GFP_ATOMIC); |
287 | else | |
288 | nskb = skb_clone(skb, GFP_ATOMIC); | |
bcbde0d4 DB |
289 | if (nskb) { |
290 | nskb->dev = dev; | |
5ffd5cdd | 291 | nskb->protocol = htons((u16) sk->sk_protocol); |
604d13c9 DB |
292 | nskb->pkt_type = netlink_is_kernel(sk) ? |
293 | PACKET_KERNEL : PACKET_USER; | |
4e48ed88 | 294 | skb_reset_network_header(nskb); |
bcbde0d4 DB |
295 | ret = dev_queue_xmit(nskb); |
296 | if (unlikely(ret > 0)) | |
297 | ret = net_xmit_errno(ret); | |
298 | } | |
299 | ||
300 | dev_put(dev); | |
301 | return ret; | |
302 | } | |
303 | ||
25e3f70f | 304 | static void __netlink_deliver_tap(struct sk_buff *skb, struct netlink_tap_net *nn) |
bcbde0d4 DB |
305 | { |
306 | int ret; | |
307 | struct netlink_tap *tmp; | |
308 | ||
5ffd5cdd DB |
309 | if (!netlink_filter_tap(skb)) |
310 | return; | |
311 | ||
25e3f70f | 312 | list_for_each_entry_rcu(tmp, &nn->netlink_tap_all, list) { |
bcbde0d4 DB |
313 | ret = __netlink_deliver_tap_skb(skb, tmp->dev); |
314 | if (unlikely(ret)) | |
315 | break; | |
316 | } | |
317 | } | |
318 | ||
25e3f70f | 319 | static void netlink_deliver_tap(struct net *net, struct sk_buff *skb) |
bcbde0d4 | 320 | { |
25e3f70f CW |
321 | struct netlink_tap_net *nn = net_generic(net, netlink_tap_net_id); |
322 | ||
bcbde0d4 DB |
323 | rcu_read_lock(); |
324 | ||
25e3f70f CW |
325 | if (unlikely(!list_empty(&nn->netlink_tap_all))) |
326 | __netlink_deliver_tap(skb, nn); | |
bcbde0d4 DB |
327 | |
328 | rcu_read_unlock(); | |
329 | } | |
330 | ||
73bfd370 DB |
331 | static void netlink_deliver_tap_kernel(struct sock *dst, struct sock *src, |
332 | struct sk_buff *skb) | |
333 | { | |
334 | if (!(netlink_is_kernel(dst) && netlink_is_kernel(src))) | |
25e3f70f | 335 | netlink_deliver_tap(sock_net(dst), skb); |
73bfd370 DB |
336 | } |
337 | ||
cd1df525 PM |
338 | static void netlink_overrun(struct sock *sk) |
339 | { | |
340 | struct netlink_sock *nlk = nlk_sk(sk); | |
341 | ||
cc3a572f ND |
342 | if (!(nlk->flags & NETLINK_F_RECV_NO_ENOBUFS)) { |
343 | if (!test_and_set_bit(NETLINK_S_CONGESTED, | |
344 | &nlk_sk(sk)->state)) { | |
cd1df525 PM |
345 | sk->sk_err = ENOBUFS; |
346 | sk->sk_error_report(sk); | |
347 | } | |
348 | } | |
349 | atomic_inc(&sk->sk_drops); | |
350 | } | |
351 | ||
352 | static void netlink_rcv_wake(struct sock *sk) | |
353 | { | |
354 | struct netlink_sock *nlk = nlk_sk(sk); | |
355 | ||
174bce38 | 356 | if (skb_queue_empty_lockless(&sk->sk_receive_queue)) |
cc3a572f ND |
357 | clear_bit(NETLINK_S_CONGESTED, &nlk->state); |
358 | if (!test_bit(NETLINK_S_CONGESTED, &nlk->state)) | |
cd1df525 PM |
359 | wake_up_interruptible(&nlk->wait); |
360 | } | |
361 | ||
cf0a018a PM |
362 | static void netlink_skb_destructor(struct sk_buff *skb) |
363 | { | |
c05cdb1b | 364 | if (is_vmalloc_addr(skb->head)) { |
3a36515f PN |
365 | if (!skb->cloned || |
366 | !atomic_dec_return(&(skb_shinfo(skb)->dataref))) | |
367 | vfree(skb->head); | |
368 | ||
c05cdb1b PNA |
369 | skb->head = NULL; |
370 | } | |
9652e931 PM |
371 | if (skb->sk != NULL) |
372 | sock_rfree(skb); | |
cf0a018a PM |
373 | } |
374 | ||
375 | static void netlink_skb_set_owner_r(struct sk_buff *skb, struct sock *sk) | |
376 | { | |
377 | WARN_ON(skb->sk != NULL); | |
378 | skb->sk = sk; | |
379 | skb->destructor = netlink_skb_destructor; | |
380 | atomic_add(skb->truesize, &sk->sk_rmem_alloc); | |
381 | sk_mem_charge(sk, skb->truesize); | |
382 | } | |
383 | ||
ed5d7788 | 384 | static void netlink_sock_destruct(struct sock *sk) |
1da177e4 | 385 | { |
3f660d66 HX |
386 | struct netlink_sock *nlk = nlk_sk(sk); |
387 | ||
16b304f3 | 388 | if (nlk->cb_running) { |
ed5d7788 HX |
389 | if (nlk->cb.done) |
390 | nlk->cb.done(&nlk->cb); | |
16b304f3 PS |
391 | module_put(nlk->cb.module); |
392 | kfree_skb(nlk->cb.skb); | |
3f660d66 HX |
393 | } |
394 | ||
1da177e4 LT |
395 | skb_queue_purge(&sk->sk_receive_queue); |
396 | ||
397 | if (!sock_flag(sk, SOCK_DEAD)) { | |
6ac552fd | 398 | printk(KERN_ERR "Freeing alive netlink socket %p\n", sk); |
1da177e4 LT |
399 | return; |
400 | } | |
547b792c IJ |
401 | |
402 | WARN_ON(atomic_read(&sk->sk_rmem_alloc)); | |
14afee4b | 403 | WARN_ON(refcount_read(&sk->sk_wmem_alloc)); |
547b792c | 404 | WARN_ON(nlk_sk(sk)->groups); |
1da177e4 LT |
405 | } |
406 | ||
707693c8 HX |
407 | static void netlink_sock_destruct_work(struct work_struct *work) |
408 | { | |
409 | struct netlink_sock *nlk = container_of(work, struct netlink_sock, | |
410 | work); | |
411 | ||
ed5d7788 | 412 | sk_free(&nlk->sk); |
707693c8 HX |
413 | } |
414 | ||
6ac552fd PM |
415 | /* This lock without WQ_FLAG_EXCLUSIVE is good on UP and it is _very_ bad on |
416 | * SMP. Look, when several writers sleep and reader wakes them up, all but one | |
1da177e4 LT |
417 | * immediately hit write lock and grab all the cpus. Exclusive sleep solves |
418 | * this, _but_ remember, it adds useless work on UP machines. | |
419 | */ | |
420 | ||
d136f1bd | 421 | void netlink_table_grab(void) |
9a429c49 | 422 | __acquires(nl_table_lock) |
1da177e4 | 423 | { |
d136f1bd JB |
424 | might_sleep(); |
425 | ||
6abd219c | 426 | write_lock_irq(&nl_table_lock); |
1da177e4 LT |
427 | |
428 | if (atomic_read(&nl_table_users)) { | |
429 | DECLARE_WAITQUEUE(wait, current); | |
430 | ||
431 | add_wait_queue_exclusive(&nl_table_wait, &wait); | |
6ac552fd | 432 | for (;;) { |
1da177e4 LT |
433 | set_current_state(TASK_UNINTERRUPTIBLE); |
434 | if (atomic_read(&nl_table_users) == 0) | |
435 | break; | |
6abd219c | 436 | write_unlock_irq(&nl_table_lock); |
1da177e4 | 437 | schedule(); |
6abd219c | 438 | write_lock_irq(&nl_table_lock); |
1da177e4 LT |
439 | } |
440 | ||
441 | __set_current_state(TASK_RUNNING); | |
442 | remove_wait_queue(&nl_table_wait, &wait); | |
443 | } | |
444 | } | |
445 | ||
d136f1bd | 446 | void netlink_table_ungrab(void) |
9a429c49 | 447 | __releases(nl_table_lock) |
1da177e4 | 448 | { |
6abd219c | 449 | write_unlock_irq(&nl_table_lock); |
1da177e4 LT |
450 | wake_up(&nl_table_wait); |
451 | } | |
452 | ||
6ac552fd | 453 | static inline void |
1da177e4 LT |
454 | netlink_lock_table(void) |
455 | { | |
456 | /* read_lock() synchronizes us to netlink_table_grab */ | |
457 | ||
458 | read_lock(&nl_table_lock); | |
459 | atomic_inc(&nl_table_users); | |
460 | read_unlock(&nl_table_lock); | |
461 | } | |
462 | ||
6ac552fd | 463 | static inline void |
1da177e4 LT |
464 | netlink_unlock_table(void) |
465 | { | |
466 | if (atomic_dec_and_test(&nl_table_users)) | |
467 | wake_up(&nl_table_wait); | |
468 | } | |
469 | ||
e341694e | 470 | struct netlink_compare_arg |
1da177e4 | 471 | { |
c428ecd1 | 472 | possible_net_t pnet; |
e341694e TG |
473 | u32 portid; |
474 | }; | |
1da177e4 | 475 | |
8f2ddaac HX |
476 | /* Doing sizeof directly may yield 4 extra bytes on 64-bit. */ |
477 | #define netlink_compare_arg_len \ | |
478 | (offsetof(struct netlink_compare_arg, portid) + sizeof(u32)) | |
c428ecd1 HX |
479 | |
480 | static inline int netlink_compare(struct rhashtable_compare_arg *arg, | |
481 | const void *ptr) | |
1da177e4 | 482 | { |
c428ecd1 HX |
483 | const struct netlink_compare_arg *x = arg->key; |
484 | const struct netlink_sock *nlk = ptr; | |
1da177e4 | 485 | |
da314c99 | 486 | return nlk->portid != x->portid || |
c428ecd1 HX |
487 | !net_eq(sock_net(&nlk->sk), read_pnet(&x->pnet)); |
488 | } | |
489 | ||
490 | static void netlink_compare_arg_init(struct netlink_compare_arg *arg, | |
491 | struct net *net, u32 portid) | |
492 | { | |
493 | memset(arg, 0, sizeof(*arg)); | |
494 | write_pnet(&arg->pnet, net); | |
495 | arg->portid = portid; | |
1da177e4 LT |
496 | } |
497 | ||
e341694e TG |
498 | static struct sock *__netlink_lookup(struct netlink_table *table, u32 portid, |
499 | struct net *net) | |
1da177e4 | 500 | { |
c428ecd1 | 501 | struct netlink_compare_arg arg; |
1da177e4 | 502 | |
c428ecd1 HX |
503 | netlink_compare_arg_init(&arg, net, portid); |
504 | return rhashtable_lookup_fast(&table->hash, &arg, | |
505 | netlink_rhashtable_params); | |
1da177e4 LT |
506 | } |
507 | ||
c428ecd1 | 508 | static int __netlink_insert(struct netlink_table *table, struct sock *sk) |
c5adde94 | 509 | { |
c428ecd1 | 510 | struct netlink_compare_arg arg; |
c5adde94 | 511 | |
da314c99 | 512 | netlink_compare_arg_init(&arg, sock_net(sk), nlk_sk(sk)->portid); |
c428ecd1 HX |
513 | return rhashtable_lookup_insert_key(&table->hash, &arg, |
514 | &nlk_sk(sk)->node, | |
515 | netlink_rhashtable_params); | |
c5adde94 YX |
516 | } |
517 | ||
e341694e | 518 | static struct sock *netlink_lookup(struct net *net, int protocol, u32 portid) |
1da177e4 | 519 | { |
e341694e TG |
520 | struct netlink_table *table = &nl_table[protocol]; |
521 | struct sock *sk; | |
1da177e4 | 522 | |
e341694e TG |
523 | rcu_read_lock(); |
524 | sk = __netlink_lookup(table, portid, net); | |
525 | if (sk) | |
526 | sock_hold(sk); | |
527 | rcu_read_unlock(); | |
1da177e4 | 528 | |
e341694e | 529 | return sk; |
1da177e4 LT |
530 | } |
531 | ||
90ddc4f0 | 532 | static const struct proto_ops netlink_ops; |
1da177e4 | 533 | |
4277a083 PM |
534 | static void |
535 | netlink_update_listeners(struct sock *sk) | |
536 | { | |
537 | struct netlink_table *tbl = &nl_table[sk->sk_protocol]; | |
4277a083 PM |
538 | unsigned long mask; |
539 | unsigned int i; | |
6d772ac5 ED |
540 | struct listeners *listeners; |
541 | ||
542 | listeners = nl_deref_protected(tbl->listeners); | |
543 | if (!listeners) | |
544 | return; | |
4277a083 | 545 | |
b4ff4f04 | 546 | for (i = 0; i < NLGRPLONGS(tbl->groups); i++) { |
4277a083 | 547 | mask = 0; |
b67bfe0d | 548 | sk_for_each_bound(sk, &tbl->mc_list) { |
b4ff4f04 JB |
549 | if (i < NLGRPLONGS(nlk_sk(sk)->ngroups)) |
550 | mask |= nlk_sk(sk)->groups[i]; | |
551 | } | |
6d772ac5 | 552 | listeners->masks[i] = mask; |
4277a083 PM |
553 | } |
554 | /* this function is only called with the netlink table "grabbed", which | |
555 | * makes sure updates are visible before bind or setsockopt return. */ | |
556 | } | |
557 | ||
8ea65f4a | 558 | static int netlink_insert(struct sock *sk, u32 portid) |
1da177e4 | 559 | { |
da12c90e | 560 | struct netlink_table *table = &nl_table[sk->sk_protocol]; |
919d9db9 | 561 | int err; |
1da177e4 | 562 | |
c5adde94 | 563 | lock_sock(sk); |
1da177e4 | 564 | |
da314c99 HX |
565 | err = nlk_sk(sk)->portid == portid ? 0 : -EBUSY; |
566 | if (nlk_sk(sk)->bound) | |
1da177e4 LT |
567 | goto err; |
568 | ||
da314c99 | 569 | nlk_sk(sk)->portid = portid; |
e341694e | 570 | sock_hold(sk); |
919d9db9 | 571 | |
c428ecd1 HX |
572 | err = __netlink_insert(table, sk); |
573 | if (err) { | |
4e7c1330 DB |
574 | /* In case the hashtable backend returns with -EBUSY |
575 | * from here, it must not escape to the caller. | |
576 | */ | |
577 | if (unlikely(err == -EBUSY)) | |
578 | err = -EOVERFLOW; | |
c428ecd1 HX |
579 | if (err == -EEXIST) |
580 | err = -EADDRINUSE; | |
c5adde94 | 581 | sock_put(sk); |
1f770c0a | 582 | goto err; |
919d9db9 HX |
583 | } |
584 | ||
da314c99 HX |
585 | /* We need to ensure that the socket is hashed and visible. */ |
586 | smp_wmb(); | |
587 | nlk_sk(sk)->bound = portid; | |
1f770c0a | 588 | |
1da177e4 | 589 | err: |
c5adde94 | 590 | release_sock(sk); |
1da177e4 LT |
591 | return err; |
592 | } | |
593 | ||
594 | static void netlink_remove(struct sock *sk) | |
595 | { | |
e341694e TG |
596 | struct netlink_table *table; |
597 | ||
e341694e | 598 | table = &nl_table[sk->sk_protocol]; |
c428ecd1 HX |
599 | if (!rhashtable_remove_fast(&table->hash, &nlk_sk(sk)->node, |
600 | netlink_rhashtable_params)) { | |
41c6d650 | 601 | WARN_ON(refcount_read(&sk->sk_refcnt) == 1); |
e341694e TG |
602 | __sock_put(sk); |
603 | } | |
e341694e | 604 | |
1da177e4 | 605 | netlink_table_grab(); |
b10dcb3b | 606 | if (nlk_sk(sk)->subscriptions) { |
1da177e4 | 607 | __sk_del_bind_node(sk); |
b10dcb3b JB |
608 | netlink_update_listeners(sk); |
609 | } | |
ee1c2442 JB |
610 | if (sk->sk_protocol == NETLINK_GENERIC) |
611 | atomic_inc(&genl_sk_destructing_cnt); | |
1da177e4 LT |
612 | netlink_table_ungrab(); |
613 | } | |
614 | ||
615 | static struct proto netlink_proto = { | |
616 | .name = "NETLINK", | |
617 | .owner = THIS_MODULE, | |
618 | .obj_size = sizeof(struct netlink_sock), | |
619 | }; | |
620 | ||
1b8d7ae4 | 621 | static int __netlink_create(struct net *net, struct socket *sock, |
11aa9c28 EB |
622 | struct mutex *cb_mutex, int protocol, |
623 | int kern) | |
1da177e4 LT |
624 | { |
625 | struct sock *sk; | |
626 | struct netlink_sock *nlk; | |
ab33a171 PM |
627 | |
628 | sock->ops = &netlink_ops; | |
629 | ||
11aa9c28 | 630 | sk = sk_alloc(net, PF_NETLINK, GFP_KERNEL, &netlink_proto, kern); |
ab33a171 PM |
631 | if (!sk) |
632 | return -ENOMEM; | |
633 | ||
634 | sock_init_data(sock, sk); | |
635 | ||
636 | nlk = nlk_sk(sk); | |
658cb354 | 637 | if (cb_mutex) { |
ffa4d721 | 638 | nlk->cb_mutex = cb_mutex; |
658cb354 | 639 | } else { |
ffa4d721 PM |
640 | nlk->cb_mutex = &nlk->cb_def_mutex; |
641 | mutex_init(nlk->cb_mutex); | |
8a0f5ccf HX |
642 | lockdep_set_class_and_name(nlk->cb_mutex, |
643 | nlk_cb_mutex_keys + protocol, | |
644 | nlk_cb_mutex_key_strings[protocol]); | |
ffa4d721 | 645 | } |
ab33a171 PM |
646 | init_waitqueue_head(&nlk->wait); |
647 | ||
648 | sk->sk_destruct = netlink_sock_destruct; | |
649 | sk->sk_protocol = protocol; | |
650 | return 0; | |
651 | } | |
652 | ||
3f378b68 EP |
653 | static int netlink_create(struct net *net, struct socket *sock, int protocol, |
654 | int kern) | |
ab33a171 PM |
655 | { |
656 | struct module *module = NULL; | |
af65bdfc | 657 | struct mutex *cb_mutex; |
f7fa9b10 | 658 | struct netlink_sock *nlk; |
023e2cfa JB |
659 | int (*bind)(struct net *net, int group); |
660 | void (*unbind)(struct net *net, int group); | |
ab33a171 | 661 | int err = 0; |
1da177e4 LT |
662 | |
663 | sock->state = SS_UNCONNECTED; | |
664 | ||
665 | if (sock->type != SOCK_RAW && sock->type != SOCK_DGRAM) | |
666 | return -ESOCKTNOSUPPORT; | |
667 | ||
6ac552fd | 668 | if (protocol < 0 || protocol >= MAX_LINKS) |
1da177e4 | 669 | return -EPROTONOSUPPORT; |
bc5b6c0b | 670 | protocol = array_index_nospec(protocol, MAX_LINKS); |
1da177e4 | 671 | |
77247bbb | 672 | netlink_lock_table(); |
95a5afca | 673 | #ifdef CONFIG_MODULES |
ab33a171 | 674 | if (!nl_table[protocol].registered) { |
77247bbb | 675 | netlink_unlock_table(); |
4fdb3bb7 | 676 | request_module("net-pf-%d-proto-%d", PF_NETLINK, protocol); |
77247bbb | 677 | netlink_lock_table(); |
4fdb3bb7 | 678 | } |
ab33a171 PM |
679 | #endif |
680 | if (nl_table[protocol].registered && | |
681 | try_module_get(nl_table[protocol].module)) | |
682 | module = nl_table[protocol].module; | |
974c37e9 AD |
683 | else |
684 | err = -EPROTONOSUPPORT; | |
af65bdfc | 685 | cb_mutex = nl_table[protocol].cb_mutex; |
03292745 | 686 | bind = nl_table[protocol].bind; |
4f520900 | 687 | unbind = nl_table[protocol].unbind; |
77247bbb | 688 | netlink_unlock_table(); |
4fdb3bb7 | 689 | |
974c37e9 AD |
690 | if (err < 0) |
691 | goto out; | |
692 | ||
11aa9c28 | 693 | err = __netlink_create(net, sock, cb_mutex, protocol, kern); |
6ac552fd | 694 | if (err < 0) |
f7fa9b10 PM |
695 | goto out_module; |
696 | ||
6f756a8c | 697 | local_bh_disable(); |
c1fd3b94 | 698 | sock_prot_inuse_add(net, &netlink_proto, 1); |
6f756a8c DM |
699 | local_bh_enable(); |
700 | ||
f7fa9b10 | 701 | nlk = nlk_sk(sock->sk); |
f7fa9b10 | 702 | nlk->module = module; |
03292745 | 703 | nlk->netlink_bind = bind; |
4f520900 | 704 | nlk->netlink_unbind = unbind; |
ab33a171 PM |
705 | out: |
706 | return err; | |
1da177e4 | 707 | |
ab33a171 PM |
708 | out_module: |
709 | module_put(module); | |
710 | goto out; | |
1da177e4 LT |
711 | } |
712 | ||
21e4902a TG |
713 | static void deferred_put_nlk_sk(struct rcu_head *head) |
714 | { | |
715 | struct netlink_sock *nlk = container_of(head, struct netlink_sock, rcu); | |
ed5d7788 HX |
716 | struct sock *sk = &nlk->sk; |
717 | ||
be82485f XL |
718 | kfree(nlk->groups); |
719 | nlk->groups = NULL; | |
720 | ||
41c6d650 | 721 | if (!refcount_dec_and_test(&sk->sk_refcnt)) |
ed5d7788 HX |
722 | return; |
723 | ||
724 | if (nlk->cb_running && nlk->cb.done) { | |
725 | INIT_WORK(&nlk->work, netlink_sock_destruct_work); | |
726 | schedule_work(&nlk->work); | |
727 | return; | |
728 | } | |
21e4902a | 729 | |
ed5d7788 | 730 | sk_free(sk); |
21e4902a TG |
731 | } |
732 | ||
1da177e4 LT |
733 | static int netlink_release(struct socket *sock) |
734 | { | |
735 | struct sock *sk = sock->sk; | |
736 | struct netlink_sock *nlk; | |
737 | ||
738 | if (!sk) | |
739 | return 0; | |
740 | ||
741 | netlink_remove(sk); | |
ac57b3a9 | 742 | sock_orphan(sk); |
1da177e4 LT |
743 | nlk = nlk_sk(sk); |
744 | ||
3f660d66 HX |
745 | /* |
746 | * OK. Socket is unlinked, any packets that arrive now | |
747 | * will be purged. | |
748 | */ | |
1da177e4 | 749 | |
ee1c2442 JB |
750 | /* must not acquire netlink_table_lock in any way again before unbind |
751 | * and notifying genetlink is done as otherwise it might deadlock | |
752 | */ | |
753 | if (nlk->netlink_unbind) { | |
754 | int i; | |
755 | ||
756 | for (i = 0; i < nlk->ngroups; i++) | |
757 | if (test_bit(i, nlk->groups)) | |
758 | nlk->netlink_unbind(sock_net(sk), i + 1); | |
759 | } | |
760 | if (sk->sk_protocol == NETLINK_GENERIC && | |
761 | atomic_dec_return(&genl_sk_destructing_cnt) == 0) | |
762 | wake_up(&genl_sk_destructing_waitq); | |
763 | ||
1da177e4 LT |
764 | sock->sk = NULL; |
765 | wake_up_interruptible_all(&nlk->wait); | |
766 | ||
767 | skb_queue_purge(&sk->sk_write_queue); | |
768 | ||
e2726020 | 769 | if (nlk->portid && nlk->bound) { |
1da177e4 | 770 | struct netlink_notify n = { |
3b1e0a65 | 771 | .net = sock_net(sk), |
1da177e4 | 772 | .protocol = sk->sk_protocol, |
15e47304 | 773 | .portid = nlk->portid, |
1da177e4 | 774 | }; |
efa172f4 | 775 | blocking_notifier_call_chain(&netlink_chain, |
e041c683 | 776 | NETLINK_URELEASE, &n); |
746fac4d | 777 | } |
4fdb3bb7 | 778 | |
5e7c001c | 779 | module_put(nlk->module); |
4fdb3bb7 | 780 | |
aed81560 | 781 | if (netlink_is_kernel(sk)) { |
b10dcb3b | 782 | netlink_table_grab(); |
869e58f8 DL |
783 | BUG_ON(nl_table[sk->sk_protocol].registered == 0); |
784 | if (--nl_table[sk->sk_protocol].registered == 0) { | |
6d772ac5 ED |
785 | struct listeners *old; |
786 | ||
787 | old = nl_deref_protected(nl_table[sk->sk_protocol].listeners); | |
788 | RCU_INIT_POINTER(nl_table[sk->sk_protocol].listeners, NULL); | |
789 | kfree_rcu(old, rcu); | |
869e58f8 | 790 | nl_table[sk->sk_protocol].module = NULL; |
9785e10a | 791 | nl_table[sk->sk_protocol].bind = NULL; |
4f520900 | 792 | nl_table[sk->sk_protocol].unbind = NULL; |
9785e10a | 793 | nl_table[sk->sk_protocol].flags = 0; |
869e58f8 DL |
794 | nl_table[sk->sk_protocol].registered = 0; |
795 | } | |
b10dcb3b | 796 | netlink_table_ungrab(); |
658cb354 | 797 | } |
77247bbb | 798 | |
3755810c | 799 | local_bh_disable(); |
c1fd3b94 | 800 | sock_prot_inuse_add(sock_net(sk), &netlink_proto, -1); |
3755810c | 801 | local_bh_enable(); |
21e4902a | 802 | call_rcu(&nlk->rcu, deferred_put_nlk_sk); |
1da177e4 LT |
803 | return 0; |
804 | } | |
805 | ||
806 | static int netlink_autobind(struct socket *sock) | |
807 | { | |
808 | struct sock *sk = sock->sk; | |
3b1e0a65 | 809 | struct net *net = sock_net(sk); |
da12c90e | 810 | struct netlink_table *table = &nl_table[sk->sk_protocol]; |
15e47304 | 811 | s32 portid = task_tgid_vnr(current); |
1da177e4 | 812 | int err; |
b9fbe709 HX |
813 | s32 rover = -4096; |
814 | bool ok; | |
1da177e4 LT |
815 | |
816 | retry: | |
817 | cond_resched(); | |
e341694e | 818 | rcu_read_lock(); |
b9fbe709 HX |
819 | ok = !__netlink_lookup(table, portid, net); |
820 | rcu_read_unlock(); | |
821 | if (!ok) { | |
e341694e | 822 | /* Bind collision, search negative portid values. */ |
b9fbe709 HX |
823 | if (rover == -4096) |
824 | /* rover will be in range [S32_MIN, -4097] */ | |
825 | rover = S32_MIN + prandom_u32_max(-4096 - S32_MIN); | |
826 | else if (rover >= -4096) | |
e341694e | 827 | rover = -4097; |
b9fbe709 | 828 | portid = rover--; |
e341694e | 829 | goto retry; |
1da177e4 | 830 | } |
1da177e4 | 831 | |
8ea65f4a | 832 | err = netlink_insert(sk, portid); |
1da177e4 LT |
833 | if (err == -EADDRINUSE) |
834 | goto retry; | |
d470e3b4 DM |
835 | |
836 | /* If 2 threads race to autobind, that is fine. */ | |
837 | if (err == -EBUSY) | |
838 | err = 0; | |
839 | ||
840 | return err; | |
1da177e4 LT |
841 | } |
842 | ||
aa4cf945 EB |
843 | /** |
844 | * __netlink_ns_capable - General netlink message capability test | |
845 | * @nsp: NETLINK_CB of the socket buffer holding a netlink command from userspace. | |
846 | * @user_ns: The user namespace of the capability to use | |
847 | * @cap: The capability to use | |
848 | * | |
849 | * Test to see if the opener of the socket we received the message | |
850 | * from had when the netlink socket was created and the sender of the | |
85405918 | 851 | * message has the capability @cap in the user namespace @user_ns. |
aa4cf945 EB |
852 | */ |
853 | bool __netlink_ns_capable(const struct netlink_skb_parms *nsp, | |
854 | struct user_namespace *user_ns, int cap) | |
855 | { | |
2d7a85f4 EB |
856 | return ((nsp->flags & NETLINK_SKB_DST) || |
857 | file_ns_capable(nsp->sk->sk_socket->file, user_ns, cap)) && | |
858 | ns_capable(user_ns, cap); | |
aa4cf945 EB |
859 | } |
860 | EXPORT_SYMBOL(__netlink_ns_capable); | |
861 | ||
862 | /** | |
863 | * netlink_ns_capable - General netlink message capability test | |
864 | * @skb: socket buffer holding a netlink command from userspace | |
865 | * @user_ns: The user namespace of the capability to use | |
866 | * @cap: The capability to use | |
867 | * | |
868 | * Test to see if the opener of the socket we received the message | |
869 | * from had when the netlink socket was created and the sender of the | |
85405918 | 870 | * message has the capability @cap in the user namespace @user_ns. |
aa4cf945 EB |
871 | */ |
872 | bool netlink_ns_capable(const struct sk_buff *skb, | |
873 | struct user_namespace *user_ns, int cap) | |
874 | { | |
875 | return __netlink_ns_capable(&NETLINK_CB(skb), user_ns, cap); | |
876 | } | |
877 | EXPORT_SYMBOL(netlink_ns_capable); | |
878 | ||
879 | /** | |
880 | * netlink_capable - Netlink global message capability test | |
881 | * @skb: socket buffer holding a netlink command from userspace | |
882 | * @cap: The capability to use | |
883 | * | |
884 | * Test to see if the opener of the socket we received the message | |
885 | * from had when the netlink socket was created and the sender of the | |
85405918 | 886 | * message has the capability @cap in all user namespaces. |
aa4cf945 EB |
887 | */ |
888 | bool netlink_capable(const struct sk_buff *skb, int cap) | |
889 | { | |
890 | return netlink_ns_capable(skb, &init_user_ns, cap); | |
891 | } | |
892 | EXPORT_SYMBOL(netlink_capable); | |
893 | ||
894 | /** | |
895 | * netlink_net_capable - Netlink network namespace message capability test | |
896 | * @skb: socket buffer holding a netlink command from userspace | |
897 | * @cap: The capability to use | |
898 | * | |
899 | * Test to see if the opener of the socket we received the message | |
900 | * from had when the netlink socket was created and the sender of the | |
85405918 | 901 | * message has the capability @cap over the network namespace of |
aa4cf945 EB |
902 | * the socket we received the message from. |
903 | */ | |
904 | bool netlink_net_capable(const struct sk_buff *skb, int cap) | |
905 | { | |
906 | return netlink_ns_capable(skb, sock_net(skb->sk)->user_ns, cap); | |
907 | } | |
908 | EXPORT_SYMBOL(netlink_net_capable); | |
909 | ||
5187cd05 | 910 | static inline int netlink_allowed(const struct socket *sock, unsigned int flag) |
746fac4d | 911 | { |
9785e10a | 912 | return (nl_table[sock->sk->sk_protocol].flags & flag) || |
df008c91 | 913 | ns_capable(sock_net(sock->sk)->user_ns, CAP_NET_ADMIN); |
746fac4d | 914 | } |
1da177e4 | 915 | |
f7fa9b10 PM |
916 | static void |
917 | netlink_update_subscriptions(struct sock *sk, unsigned int subscriptions) | |
918 | { | |
919 | struct netlink_sock *nlk = nlk_sk(sk); | |
920 | ||
921 | if (nlk->subscriptions && !subscriptions) | |
922 | __sk_del_bind_node(sk); | |
923 | else if (!nlk->subscriptions && subscriptions) | |
924 | sk_add_bind_node(sk, &nl_table[sk->sk_protocol].mc_list); | |
925 | nlk->subscriptions = subscriptions; | |
926 | } | |
927 | ||
b4ff4f04 | 928 | static int netlink_realloc_groups(struct sock *sk) |
513c2500 PM |
929 | { |
930 | struct netlink_sock *nlk = nlk_sk(sk); | |
931 | unsigned int groups; | |
b4ff4f04 | 932 | unsigned long *new_groups; |
513c2500 PM |
933 | int err = 0; |
934 | ||
b4ff4f04 JB |
935 | netlink_table_grab(); |
936 | ||
513c2500 | 937 | groups = nl_table[sk->sk_protocol].groups; |
b4ff4f04 | 938 | if (!nl_table[sk->sk_protocol].registered) { |
513c2500 | 939 | err = -ENOENT; |
b4ff4f04 JB |
940 | goto out_unlock; |
941 | } | |
513c2500 | 942 | |
b4ff4f04 JB |
943 | if (nlk->ngroups >= groups) |
944 | goto out_unlock; | |
513c2500 | 945 | |
b4ff4f04 JB |
946 | new_groups = krealloc(nlk->groups, NLGRPSZ(groups), GFP_ATOMIC); |
947 | if (new_groups == NULL) { | |
948 | err = -ENOMEM; | |
949 | goto out_unlock; | |
950 | } | |
6ac552fd | 951 | memset((char *)new_groups + NLGRPSZ(nlk->ngroups), 0, |
b4ff4f04 JB |
952 | NLGRPSZ(groups) - NLGRPSZ(nlk->ngroups)); |
953 | ||
954 | nlk->groups = new_groups; | |
513c2500 | 955 | nlk->ngroups = groups; |
b4ff4f04 JB |
956 | out_unlock: |
957 | netlink_table_ungrab(); | |
958 | return err; | |
513c2500 PM |
959 | } |
960 | ||
02c81ab9 | 961 | static void netlink_undo_bind(int group, long unsigned int groups, |
023e2cfa | 962 | struct sock *sk) |
4f520900 | 963 | { |
023e2cfa | 964 | struct netlink_sock *nlk = nlk_sk(sk); |
4f520900 RGB |
965 | int undo; |
966 | ||
967 | if (!nlk->netlink_unbind) | |
968 | return; | |
969 | ||
970 | for (undo = 0; undo < group; undo++) | |
6251edd9 | 971 | if (test_bit(undo, &groups)) |
8b7c36d8 | 972 | nlk->netlink_unbind(sock_net(sk), undo + 1); |
4f520900 RGB |
973 | } |
974 | ||
6ac552fd PM |
975 | static int netlink_bind(struct socket *sock, struct sockaddr *addr, |
976 | int addr_len) | |
1da177e4 LT |
977 | { |
978 | struct sock *sk = sock->sk; | |
3b1e0a65 | 979 | struct net *net = sock_net(sk); |
1da177e4 LT |
980 | struct netlink_sock *nlk = nlk_sk(sk); |
981 | struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; | |
f7736080 | 982 | int err = 0; |
d852be84 | 983 | unsigned long groups; |
da314c99 | 984 | bool bound; |
746fac4d | 985 | |
4e4b5376 HFS |
986 | if (addr_len < sizeof(struct sockaddr_nl)) |
987 | return -EINVAL; | |
988 | ||
1da177e4 LT |
989 | if (nladdr->nl_family != AF_NETLINK) |
990 | return -EINVAL; | |
d852be84 | 991 | groups = nladdr->nl_groups; |
1da177e4 LT |
992 | |
993 | /* Only superuser is allowed to listen multicasts */ | |
4f520900 | 994 | if (groups) { |
5187cd05 | 995 | if (!netlink_allowed(sock, NL_CFG_F_NONROOT_RECV)) |
513c2500 | 996 | return -EPERM; |
b4ff4f04 JB |
997 | err = netlink_realloc_groups(sk); |
998 | if (err) | |
999 | return err; | |
513c2500 | 1000 | } |
1da177e4 | 1001 | |
428f944b | 1002 | if (nlk->ngroups < BITS_PER_LONG) |
91874ecf | 1003 | groups &= (1UL << nlk->ngroups) - 1; |
1da177e4 | 1004 | |
da314c99 HX |
1005 | bound = nlk->bound; |
1006 | if (bound) { | |
1007 | /* Ensure nlk->portid is up-to-date. */ | |
1008 | smp_rmb(); | |
1009 | ||
15e47304 | 1010 | if (nladdr->nl_pid != nlk->portid) |
1da177e4 | 1011 | return -EINVAL; |
da314c99 | 1012 | } |
4f520900 | 1013 | |
f7736080 | 1014 | netlink_lock_table(); |
4f520900 RGB |
1015 | if (nlk->netlink_bind && groups) { |
1016 | int group; | |
1017 | ||
3a20773b NA |
1018 | /* nl_groups is a u32, so cap the maximum groups we can bind */ |
1019 | for (group = 0; group < BITS_PER_TYPE(u32); group++) { | |
4f520900 RGB |
1020 | if (!test_bit(group, &groups)) |
1021 | continue; | |
8b7c36d8 | 1022 | err = nlk->netlink_bind(net, group + 1); |
4f520900 RGB |
1023 | if (!err) |
1024 | continue; | |
023e2cfa | 1025 | netlink_undo_bind(group, groups, sk); |
f7736080 | 1026 | goto unlock; |
4f520900 RGB |
1027 | } |
1028 | } | |
1029 | ||
da314c99 HX |
1030 | /* No need for barriers here as we return to user-space without |
1031 | * using any of the bound attributes. | |
1032 | */ | |
1033 | if (!bound) { | |
1da177e4 | 1034 | err = nladdr->nl_pid ? |
8ea65f4a | 1035 | netlink_insert(sk, nladdr->nl_pid) : |
1da177e4 | 1036 | netlink_autobind(sock); |
4f520900 | 1037 | if (err) { |
3a20773b | 1038 | netlink_undo_bind(BITS_PER_TYPE(u32), groups, sk); |
f7736080 | 1039 | goto unlock; |
4f520900 | 1040 | } |
1da177e4 LT |
1041 | } |
1042 | ||
4f520900 | 1043 | if (!groups && (nlk->groups == NULL || !(u32)nlk->groups[0])) |
f7736080 XL |
1044 | goto unlock; |
1045 | netlink_unlock_table(); | |
1da177e4 LT |
1046 | |
1047 | netlink_table_grab(); | |
f7fa9b10 | 1048 | netlink_update_subscriptions(sk, nlk->subscriptions + |
4f520900 | 1049 | hweight32(groups) - |
746fac4d | 1050 | hweight32(nlk->groups[0])); |
4f520900 | 1051 | nlk->groups[0] = (nlk->groups[0] & ~0xffffffffUL) | groups; |
4277a083 | 1052 | netlink_update_listeners(sk); |
1da177e4 LT |
1053 | netlink_table_ungrab(); |
1054 | ||
1055 | return 0; | |
f7736080 XL |
1056 | |
1057 | unlock: | |
1058 | netlink_unlock_table(); | |
1059 | return err; | |
1da177e4 LT |
1060 | } |
1061 | ||
1062 | static int netlink_connect(struct socket *sock, struct sockaddr *addr, | |
1063 | int alen, int flags) | |
1064 | { | |
1065 | int err = 0; | |
1066 | struct sock *sk = sock->sk; | |
1067 | struct netlink_sock *nlk = nlk_sk(sk); | |
6ac552fd | 1068 | struct sockaddr_nl *nladdr = (struct sockaddr_nl *)addr; |
1da177e4 | 1069 | |
6503d961 CG |
1070 | if (alen < sizeof(addr->sa_family)) |
1071 | return -EINVAL; | |
1072 | ||
1da177e4 LT |
1073 | if (addr->sa_family == AF_UNSPEC) { |
1074 | sk->sk_state = NETLINK_UNCONNECTED; | |
15e47304 | 1075 | nlk->dst_portid = 0; |
d629b836 | 1076 | nlk->dst_group = 0; |
1da177e4 LT |
1077 | return 0; |
1078 | } | |
1079 | if (addr->sa_family != AF_NETLINK) | |
1080 | return -EINVAL; | |
1081 | ||
78802879 AP |
1082 | if (alen < sizeof(struct sockaddr_nl)) |
1083 | return -EINVAL; | |
1084 | ||
46833a86 | 1085 | if ((nladdr->nl_groups || nladdr->nl_pid) && |
5187cd05 | 1086 | !netlink_allowed(sock, NL_CFG_F_NONROOT_SEND)) |
1da177e4 LT |
1087 | return -EPERM; |
1088 | ||
da314c99 HX |
1089 | /* No need for barriers here as we return to user-space without |
1090 | * using any of the bound attributes. | |
1091 | */ | |
1092 | if (!nlk->bound) | |
1da177e4 LT |
1093 | err = netlink_autobind(sock); |
1094 | ||
1095 | if (err == 0) { | |
1096 | sk->sk_state = NETLINK_CONNECTED; | |
15e47304 | 1097 | nlk->dst_portid = nladdr->nl_pid; |
d629b836 | 1098 | nlk->dst_group = ffs(nladdr->nl_groups); |
1da177e4 LT |
1099 | } |
1100 | ||
1101 | return err; | |
1102 | } | |
1103 | ||
6ac552fd | 1104 | static int netlink_getname(struct socket *sock, struct sockaddr *addr, |
9b2c45d4 | 1105 | int peer) |
1da177e4 LT |
1106 | { |
1107 | struct sock *sk = sock->sk; | |
1108 | struct netlink_sock *nlk = nlk_sk(sk); | |
13cfa97b | 1109 | DECLARE_SOCKADDR(struct sockaddr_nl *, nladdr, addr); |
746fac4d | 1110 | |
1da177e4 LT |
1111 | nladdr->nl_family = AF_NETLINK; |
1112 | nladdr->nl_pad = 0; | |
1da177e4 LT |
1113 | |
1114 | if (peer) { | |
15e47304 | 1115 | nladdr->nl_pid = nlk->dst_portid; |
d629b836 | 1116 | nladdr->nl_groups = netlink_group_mask(nlk->dst_group); |
1da177e4 | 1117 | } else { |
15e47304 | 1118 | nladdr->nl_pid = nlk->portid; |
f7736080 | 1119 | netlink_lock_table(); |
513c2500 | 1120 | nladdr->nl_groups = nlk->groups ? nlk->groups[0] : 0; |
f7736080 | 1121 | netlink_unlock_table(); |
1da177e4 | 1122 | } |
9b2c45d4 | 1123 | return sizeof(*nladdr); |
1da177e4 LT |
1124 | } |
1125 | ||
025c6818 DD |
1126 | static int netlink_ioctl(struct socket *sock, unsigned int cmd, |
1127 | unsigned long arg) | |
1128 | { | |
1129 | /* try to hand this ioctl down to the NIC drivers. | |
1130 | */ | |
1131 | return -ENOIOCTLCMD; | |
1132 | } | |
1133 | ||
15e47304 | 1134 | static struct sock *netlink_getsockbyportid(struct sock *ssk, u32 portid) |
1da177e4 | 1135 | { |
1da177e4 LT |
1136 | struct sock *sock; |
1137 | struct netlink_sock *nlk; | |
1138 | ||
15e47304 | 1139 | sock = netlink_lookup(sock_net(ssk), ssk->sk_protocol, portid); |
1da177e4 LT |
1140 | if (!sock) |
1141 | return ERR_PTR(-ECONNREFUSED); | |
1142 | ||
1143 | /* Don't bother queuing skb if kernel socket has no input function */ | |
1144 | nlk = nlk_sk(sock); | |
cd40b7d3 | 1145 | if (sock->sk_state == NETLINK_CONNECTED && |
15e47304 | 1146 | nlk->dst_portid != nlk_sk(ssk)->portid) { |
1da177e4 LT |
1147 | sock_put(sock); |
1148 | return ERR_PTR(-ECONNREFUSED); | |
1149 | } | |
1150 | return sock; | |
1151 | } | |
1152 | ||
1153 | struct sock *netlink_getsockbyfilp(struct file *filp) | |
1154 | { | |
496ad9aa | 1155 | struct inode *inode = file_inode(filp); |
1da177e4 LT |
1156 | struct sock *sock; |
1157 | ||
1158 | if (!S_ISSOCK(inode->i_mode)) | |
1159 | return ERR_PTR(-ENOTSOCK); | |
1160 | ||
1161 | sock = SOCKET_I(inode)->sk; | |
1162 | if (sock->sk_family != AF_NETLINK) | |
1163 | return ERR_PTR(-EINVAL); | |
1164 | ||
1165 | sock_hold(sock); | |
1166 | return sock; | |
1167 | } | |
1168 | ||
3a36515f PN |
1169 | static struct sk_buff *netlink_alloc_large_skb(unsigned int size, |
1170 | int broadcast) | |
c05cdb1b PNA |
1171 | { |
1172 | struct sk_buff *skb; | |
1173 | void *data; | |
1174 | ||
3a36515f | 1175 | if (size <= NLMSG_GOODSIZE || broadcast) |
c05cdb1b PNA |
1176 | return alloc_skb(size, GFP_KERNEL); |
1177 | ||
3a36515f PN |
1178 | size = SKB_DATA_ALIGN(size) + |
1179 | SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); | |
c05cdb1b PNA |
1180 | |
1181 | data = vmalloc(size); | |
1182 | if (data == NULL) | |
3a36515f | 1183 | return NULL; |
c05cdb1b | 1184 | |
2ea2f62c | 1185 | skb = __build_skb(data, size); |
3a36515f PN |
1186 | if (skb == NULL) |
1187 | vfree(data); | |
2ea2f62c | 1188 | else |
3a36515f | 1189 | skb->destructor = netlink_skb_destructor; |
c05cdb1b PNA |
1190 | |
1191 | return skb; | |
c05cdb1b PNA |
1192 | } |
1193 | ||
1da177e4 LT |
1194 | /* |
1195 | * Attach a skb to a netlink socket. | |
1196 | * The caller must hold a reference to the destination socket. On error, the | |
1197 | * reference is dropped. The skb is not send to the destination, just all | |
1198 | * all error checks are performed and memory in the queue is reserved. | |
1199 | * Return values: | |
1200 | * < 0: error. skb freed, reference to sock dropped. | |
1201 | * 0: continue | |
1202 | * 1: repeat lookup - reference dropped while waiting for socket memory. | |
1203 | */ | |
9457afee | 1204 | int netlink_attachskb(struct sock *sk, struct sk_buff *skb, |
c3d8d1e3 | 1205 | long *timeo, struct sock *ssk) |
1da177e4 LT |
1206 | { |
1207 | struct netlink_sock *nlk; | |
1208 | ||
1209 | nlk = nlk_sk(sk); | |
1210 | ||
5fd96123 | 1211 | if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || |
d1b4c689 | 1212 | test_bit(NETLINK_S_CONGESTED, &nlk->state))) { |
1da177e4 | 1213 | DECLARE_WAITQUEUE(wait, current); |
c3d8d1e3 | 1214 | if (!*timeo) { |
aed81560 | 1215 | if (!ssk || netlink_is_kernel(ssk)) |
1da177e4 LT |
1216 | netlink_overrun(sk); |
1217 | sock_put(sk); | |
1218 | kfree_skb(skb); | |
1219 | return -EAGAIN; | |
1220 | } | |
1221 | ||
1222 | __set_current_state(TASK_INTERRUPTIBLE); | |
1223 | add_wait_queue(&nlk->wait, &wait); | |
1224 | ||
1225 | if ((atomic_read(&sk->sk_rmem_alloc) > sk->sk_rcvbuf || | |
cc3a572f | 1226 | test_bit(NETLINK_S_CONGESTED, &nlk->state)) && |
1da177e4 | 1227 | !sock_flag(sk, SOCK_DEAD)) |
c3d8d1e3 | 1228 | *timeo = schedule_timeout(*timeo); |
1da177e4 LT |
1229 | |
1230 | __set_current_state(TASK_RUNNING); | |
1231 | remove_wait_queue(&nlk->wait, &wait); | |
1232 | sock_put(sk); | |
1233 | ||
1234 | if (signal_pending(current)) { | |
1235 | kfree_skb(skb); | |
c3d8d1e3 | 1236 | return sock_intr_errno(*timeo); |
1da177e4 LT |
1237 | } |
1238 | return 1; | |
1239 | } | |
cf0a018a | 1240 | netlink_skb_set_owner_r(skb, sk); |
1da177e4 LT |
1241 | return 0; |
1242 | } | |
1243 | ||
4a7e7c2a | 1244 | static int __netlink_sendskb(struct sock *sk, struct sk_buff *skb) |
1da177e4 | 1245 | { |
1da177e4 LT |
1246 | int len = skb->len; |
1247 | ||
25e3f70f | 1248 | netlink_deliver_tap(sock_net(sk), skb); |
bcbde0d4 | 1249 | |
d1b4c689 | 1250 | skb_queue_tail(&sk->sk_receive_queue, skb); |
676d2369 | 1251 | sk->sk_data_ready(sk); |
4a7e7c2a ED |
1252 | return len; |
1253 | } | |
1254 | ||
1255 | int netlink_sendskb(struct sock *sk, struct sk_buff *skb) | |
1256 | { | |
1257 | int len = __netlink_sendskb(sk, skb); | |
1258 | ||
1da177e4 LT |
1259 | sock_put(sk); |
1260 | return len; | |
1261 | } | |
1262 | ||
1263 | void netlink_detachskb(struct sock *sk, struct sk_buff *skb) | |
1264 | { | |
1265 | kfree_skb(skb); | |
1266 | sock_put(sk); | |
1267 | } | |
1268 | ||
b57ef81f | 1269 | static struct sk_buff *netlink_trim(struct sk_buff *skb, gfp_t allocation) |
1da177e4 LT |
1270 | { |
1271 | int delta; | |
1272 | ||
1298ca46 | 1273 | WARN_ON(skb->sk != NULL); |
4305b541 | 1274 | delta = skb->end - skb->tail; |
c05cdb1b | 1275 | if (is_vmalloc_addr(skb->head) || delta * 2 < skb->truesize) |
1da177e4 LT |
1276 | return skb; |
1277 | ||
1278 | if (skb_shared(skb)) { | |
1279 | struct sk_buff *nskb = skb_clone(skb, allocation); | |
1280 | if (!nskb) | |
1281 | return skb; | |
8460c00f | 1282 | consume_skb(skb); |
1da177e4 LT |
1283 | skb = nskb; |
1284 | } | |
1285 | ||
158f323b ED |
1286 | pskb_expand_head(skb, 0, -delta, |
1287 | (allocation & ~__GFP_DIRECT_RECLAIM) | | |
1288 | __GFP_NOWARN | __GFP_NORETRY); | |
1da177e4 LT |
1289 | return skb; |
1290 | } | |
1291 | ||
3fbc2905 EB |
1292 | static int netlink_unicast_kernel(struct sock *sk, struct sk_buff *skb, |
1293 | struct sock *ssk) | |
cd40b7d3 DL |
1294 | { |
1295 | int ret; | |
1296 | struct netlink_sock *nlk = nlk_sk(sk); | |
1297 | ||
1298 | ret = -ECONNREFUSED; | |
1299 | if (nlk->netlink_rcv != NULL) { | |
1300 | ret = skb->len; | |
cf0a018a | 1301 | netlink_skb_set_owner_r(skb, sk); |
e32123e5 | 1302 | NETLINK_CB(skb).sk = ssk; |
73bfd370 | 1303 | netlink_deliver_tap_kernel(sk, ssk, skb); |
cd40b7d3 | 1304 | nlk->netlink_rcv(skb); |
bfb253c9 ED |
1305 | consume_skb(skb); |
1306 | } else { | |
1307 | kfree_skb(skb); | |
cd40b7d3 | 1308 | } |
cd40b7d3 DL |
1309 | sock_put(sk); |
1310 | return ret; | |
1311 | } | |
1312 | ||
1313 | int netlink_unicast(struct sock *ssk, struct sk_buff *skb, | |
15e47304 | 1314 | u32 portid, int nonblock) |
1da177e4 LT |
1315 | { |
1316 | struct sock *sk; | |
1317 | int err; | |
1318 | long timeo; | |
1319 | ||
1320 | skb = netlink_trim(skb, gfp_any()); | |
1321 | ||
1322 | timeo = sock_sndtimeo(ssk, nonblock); | |
1323 | retry: | |
15e47304 | 1324 | sk = netlink_getsockbyportid(ssk, portid); |
1da177e4 LT |
1325 | if (IS_ERR(sk)) { |
1326 | kfree_skb(skb); | |
1327 | return PTR_ERR(sk); | |
1328 | } | |
cd40b7d3 | 1329 | if (netlink_is_kernel(sk)) |
3fbc2905 | 1330 | return netlink_unicast_kernel(sk, skb, ssk); |
cd40b7d3 | 1331 | |
b1153f29 | 1332 | if (sk_filter(sk, skb)) { |
84874607 | 1333 | err = skb->len; |
b1153f29 SH |
1334 | kfree_skb(skb); |
1335 | sock_put(sk); | |
1336 | return err; | |
1337 | } | |
1338 | ||
9457afee | 1339 | err = netlink_attachskb(sk, skb, &timeo, ssk); |
1da177e4 LT |
1340 | if (err == 1) |
1341 | goto retry; | |
1342 | if (err) | |
1343 | return err; | |
1344 | ||
7ee015e0 | 1345 | return netlink_sendskb(sk, skb); |
1da177e4 | 1346 | } |
6ac552fd | 1347 | EXPORT_SYMBOL(netlink_unicast); |
1da177e4 | 1348 | |
4277a083 PM |
1349 | int netlink_has_listeners(struct sock *sk, unsigned int group) |
1350 | { | |
1351 | int res = 0; | |
5c398dc8 | 1352 | struct listeners *listeners; |
4277a083 | 1353 | |
aed81560 | 1354 | BUG_ON(!netlink_is_kernel(sk)); |
b4ff4f04 JB |
1355 | |
1356 | rcu_read_lock(); | |
1357 | listeners = rcu_dereference(nl_table[sk->sk_protocol].listeners); | |
1358 | ||
6d772ac5 | 1359 | if (listeners && group - 1 < nl_table[sk->sk_protocol].groups) |
5c398dc8 | 1360 | res = test_bit(group - 1, listeners->masks); |
b4ff4f04 JB |
1361 | |
1362 | rcu_read_unlock(); | |
1363 | ||
4277a083 PM |
1364 | return res; |
1365 | } | |
1366 | EXPORT_SYMBOL_GPL(netlink_has_listeners); | |
1367 | ||
59c28058 JK |
1368 | bool netlink_strict_get_check(struct sk_buff *skb) |
1369 | { | |
1370 | const struct netlink_sock *nlk = nlk_sk(NETLINK_CB(skb).sk); | |
1371 | ||
1372 | return nlk->flags & NETLINK_F_STRICT_CHK; | |
1373 | } | |
1374 | EXPORT_SYMBOL_GPL(netlink_strict_get_check); | |
1375 | ||
b57ef81f | 1376 | static int netlink_broadcast_deliver(struct sock *sk, struct sk_buff *skb) |
1da177e4 LT |
1377 | { |
1378 | struct netlink_sock *nlk = nlk_sk(sk); | |
1379 | ||
1380 | if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf && | |
cc3a572f | 1381 | !test_bit(NETLINK_S_CONGESTED, &nlk->state)) { |
cf0a018a | 1382 | netlink_skb_set_owner_r(skb, sk); |
4a7e7c2a | 1383 | __netlink_sendskb(sk, skb); |
2c645800 | 1384 | return atomic_read(&sk->sk_rmem_alloc) > (sk->sk_rcvbuf >> 1); |
1da177e4 LT |
1385 | } |
1386 | return -1; | |
1387 | } | |
1388 | ||
1389 | struct netlink_broadcast_data { | |
1390 | struct sock *exclude_sk; | |
b4b51029 | 1391 | struct net *net; |
15e47304 | 1392 | u32 portid; |
1da177e4 LT |
1393 | u32 group; |
1394 | int failure; | |
ff491a73 | 1395 | int delivery_failure; |
1da177e4 LT |
1396 | int congested; |
1397 | int delivered; | |
7d877f3b | 1398 | gfp_t allocation; |
1da177e4 | 1399 | struct sk_buff *skb, *skb2; |
910a7e90 EB |
1400 | int (*tx_filter)(struct sock *dsk, struct sk_buff *skb, void *data); |
1401 | void *tx_data; | |
1da177e4 LT |
1402 | }; |
1403 | ||
46c9521f RR |
1404 | static void do_one_broadcast(struct sock *sk, |
1405 | struct netlink_broadcast_data *p) | |
1da177e4 LT |
1406 | { |
1407 | struct netlink_sock *nlk = nlk_sk(sk); | |
1408 | int val; | |
1409 | ||
1410 | if (p->exclude_sk == sk) | |
46c9521f | 1411 | return; |
1da177e4 | 1412 | |
15e47304 | 1413 | if (nlk->portid == p->portid || p->group - 1 >= nlk->ngroups || |
f7fa9b10 | 1414 | !test_bit(p->group - 1, nlk->groups)) |
46c9521f | 1415 | return; |
1da177e4 | 1416 | |
59324cf3 ND |
1417 | if (!net_eq(sock_net(sk), p->net)) { |
1418 | if (!(nlk->flags & NETLINK_F_LISTEN_ALL_NSID)) | |
1419 | return; | |
1420 | ||
1421 | if (!peernet_has_id(sock_net(sk), p->net)) | |
1422 | return; | |
1423 | ||
1424 | if (!file_ns_capable(sk->sk_socket->file, p->net->user_ns, | |
1425 | CAP_NET_BROADCAST)) | |
1426 | return; | |
1427 | } | |
b4b51029 | 1428 | |
1da177e4 LT |
1429 | if (p->failure) { |
1430 | netlink_overrun(sk); | |
46c9521f | 1431 | return; |
1da177e4 LT |
1432 | } |
1433 | ||
1434 | sock_hold(sk); | |
1435 | if (p->skb2 == NULL) { | |
68acc024 | 1436 | if (skb_shared(p->skb)) { |
1da177e4 LT |
1437 | p->skb2 = skb_clone(p->skb, p->allocation); |
1438 | } else { | |
68acc024 TC |
1439 | p->skb2 = skb_get(p->skb); |
1440 | /* | |
1441 | * skb ownership may have been set when | |
1442 | * delivered to a previous socket. | |
1443 | */ | |
1444 | skb_orphan(p->skb2); | |
1da177e4 LT |
1445 | } |
1446 | } | |
1447 | if (p->skb2 == NULL) { | |
1448 | netlink_overrun(sk); | |
1449 | /* Clone failed. Notify ALL listeners. */ | |
1450 | p->failure = 1; | |
cc3a572f | 1451 | if (nlk->flags & NETLINK_F_BROADCAST_SEND_ERROR) |
be0c22a4 | 1452 | p->delivery_failure = 1; |
59324cf3 ND |
1453 | goto out; |
1454 | } | |
1455 | if (p->tx_filter && p->tx_filter(sk, p->skb2, p->tx_data)) { | |
910a7e90 EB |
1456 | kfree_skb(p->skb2); |
1457 | p->skb2 = NULL; | |
59324cf3 ND |
1458 | goto out; |
1459 | } | |
1460 | if (sk_filter(sk, p->skb2)) { | |
b1153f29 SH |
1461 | kfree_skb(p->skb2); |
1462 | p->skb2 = NULL; | |
59324cf3 ND |
1463 | goto out; |
1464 | } | |
1465 | NETLINK_CB(p->skb2).nsid = peernet2id(sock_net(sk), p->net); | |
7212462f ND |
1466 | if (NETLINK_CB(p->skb2).nsid != NETNSA_NSID_NOT_ASSIGNED) |
1467 | NETLINK_CB(p->skb2).nsid_is_set = true; | |
59324cf3 ND |
1468 | val = netlink_broadcast_deliver(sk, p->skb2); |
1469 | if (val < 0) { | |
1da177e4 | 1470 | netlink_overrun(sk); |
cc3a572f | 1471 | if (nlk->flags & NETLINK_F_BROADCAST_SEND_ERROR) |
be0c22a4 | 1472 | p->delivery_failure = 1; |
1da177e4 LT |
1473 | } else { |
1474 | p->congested |= val; | |
1475 | p->delivered = 1; | |
1476 | p->skb2 = NULL; | |
1477 | } | |
59324cf3 | 1478 | out: |
1da177e4 | 1479 | sock_put(sk); |
1da177e4 LT |
1480 | } |
1481 | ||
15e47304 | 1482 | int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb, u32 portid, |
910a7e90 EB |
1483 | u32 group, gfp_t allocation, |
1484 | int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data), | |
1485 | void *filter_data) | |
1da177e4 | 1486 | { |
3b1e0a65 | 1487 | struct net *net = sock_net(ssk); |
1da177e4 | 1488 | struct netlink_broadcast_data info; |
1da177e4 LT |
1489 | struct sock *sk; |
1490 | ||
1491 | skb = netlink_trim(skb, allocation); | |
1492 | ||
1493 | info.exclude_sk = ssk; | |
b4b51029 | 1494 | info.net = net; |
15e47304 | 1495 | info.portid = portid; |
1da177e4 LT |
1496 | info.group = group; |
1497 | info.failure = 0; | |
ff491a73 | 1498 | info.delivery_failure = 0; |
1da177e4 LT |
1499 | info.congested = 0; |
1500 | info.delivered = 0; | |
1501 | info.allocation = allocation; | |
1502 | info.skb = skb; | |
1503 | info.skb2 = NULL; | |
910a7e90 EB |
1504 | info.tx_filter = filter; |
1505 | info.tx_data = filter_data; | |
1da177e4 LT |
1506 | |
1507 | /* While we sleep in clone, do not allow to change socket list */ | |
1508 | ||
1509 | netlink_lock_table(); | |
1510 | ||
b67bfe0d | 1511 | sk_for_each_bound(sk, &nl_table[ssk->sk_protocol].mc_list) |
1da177e4 LT |
1512 | do_one_broadcast(sk, &info); |
1513 | ||
70d4bf6d | 1514 | consume_skb(skb); |
aa1c6a6f | 1515 | |
1da177e4 LT |
1516 | netlink_unlock_table(); |
1517 | ||
70d4bf6d NH |
1518 | if (info.delivery_failure) { |
1519 | kfree_skb(info.skb2); | |
ff491a73 | 1520 | return -ENOBUFS; |
658cb354 ED |
1521 | } |
1522 | consume_skb(info.skb2); | |
ff491a73 | 1523 | |
1da177e4 | 1524 | if (info.delivered) { |
d0164adc | 1525 | if (info.congested && gfpflags_allow_blocking(allocation)) |
1da177e4 LT |
1526 | yield(); |
1527 | return 0; | |
1528 | } | |
1da177e4 LT |
1529 | return -ESRCH; |
1530 | } | |
910a7e90 EB |
1531 | EXPORT_SYMBOL(netlink_broadcast_filtered); |
1532 | ||
15e47304 | 1533 | int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, u32 portid, |
910a7e90 EB |
1534 | u32 group, gfp_t allocation) |
1535 | { | |
15e47304 | 1536 | return netlink_broadcast_filtered(ssk, skb, portid, group, allocation, |
910a7e90 EB |
1537 | NULL, NULL); |
1538 | } | |
6ac552fd | 1539 | EXPORT_SYMBOL(netlink_broadcast); |
1da177e4 LT |
1540 | |
1541 | struct netlink_set_err_data { | |
1542 | struct sock *exclude_sk; | |
15e47304 | 1543 | u32 portid; |
1da177e4 LT |
1544 | u32 group; |
1545 | int code; | |
1546 | }; | |
1547 | ||
b57ef81f | 1548 | static int do_one_set_err(struct sock *sk, struct netlink_set_err_data *p) |
1da177e4 LT |
1549 | { |
1550 | struct netlink_sock *nlk = nlk_sk(sk); | |
1a50307b | 1551 | int ret = 0; |
1da177e4 LT |
1552 | |
1553 | if (sk == p->exclude_sk) | |
1554 | goto out; | |
1555 | ||
09ad9bc7 | 1556 | if (!net_eq(sock_net(sk), sock_net(p->exclude_sk))) |
b4b51029 EB |
1557 | goto out; |
1558 | ||
15e47304 | 1559 | if (nlk->portid == p->portid || p->group - 1 >= nlk->ngroups || |
f7fa9b10 | 1560 | !test_bit(p->group - 1, nlk->groups)) |
1da177e4 LT |
1561 | goto out; |
1562 | ||
cc3a572f | 1563 | if (p->code == ENOBUFS && nlk->flags & NETLINK_F_RECV_NO_ENOBUFS) { |
1a50307b PNA |
1564 | ret = 1; |
1565 | goto out; | |
1566 | } | |
1567 | ||
1da177e4 LT |
1568 | sk->sk_err = p->code; |
1569 | sk->sk_error_report(sk); | |
1570 | out: | |
1a50307b | 1571 | return ret; |
1da177e4 LT |
1572 | } |
1573 | ||
4843b93c PNA |
1574 | /** |
1575 | * netlink_set_err - report error to broadcast listeners | |
1576 | * @ssk: the kernel netlink socket, as returned by netlink_kernel_create() | |
15e47304 | 1577 | * @portid: the PORTID of a process that we want to skip (if any) |
840e93f2 | 1578 | * @group: the broadcast group that will notice the error |
4843b93c | 1579 | * @code: error code, must be negative (as usual in kernelspace) |
1a50307b PNA |
1580 | * |
1581 | * This function returns the number of broadcast listeners that have set the | |
cc3a572f | 1582 | * NETLINK_NO_ENOBUFS socket option. |
4843b93c | 1583 | */ |
15e47304 | 1584 | int netlink_set_err(struct sock *ssk, u32 portid, u32 group, int code) |
1da177e4 LT |
1585 | { |
1586 | struct netlink_set_err_data info; | |
1da177e4 | 1587 | struct sock *sk; |
1a50307b | 1588 | int ret = 0; |
1da177e4 LT |
1589 | |
1590 | info.exclude_sk = ssk; | |
15e47304 | 1591 | info.portid = portid; |
1da177e4 | 1592 | info.group = group; |
4843b93c PNA |
1593 | /* sk->sk_err wants a positive error value */ |
1594 | info.code = -code; | |
1da177e4 LT |
1595 | |
1596 | read_lock(&nl_table_lock); | |
1597 | ||
b67bfe0d | 1598 | sk_for_each_bound(sk, &nl_table[ssk->sk_protocol].mc_list) |
1a50307b | 1599 | ret += do_one_set_err(sk, &info); |
1da177e4 LT |
1600 | |
1601 | read_unlock(&nl_table_lock); | |
1a50307b | 1602 | return ret; |
1da177e4 | 1603 | } |
dd5b6ce6 | 1604 | EXPORT_SYMBOL(netlink_set_err); |
1da177e4 | 1605 | |
84659eb5 JB |
1606 | /* must be called with netlink table grabbed */ |
1607 | static void netlink_update_socket_mc(struct netlink_sock *nlk, | |
1608 | unsigned int group, | |
1609 | int is_new) | |
1610 | { | |
1611 | int old, new = !!is_new, subscriptions; | |
1612 | ||
1613 | old = test_bit(group - 1, nlk->groups); | |
1614 | subscriptions = nlk->subscriptions - old + new; | |
1615 | if (new) | |
1616 | __set_bit(group - 1, nlk->groups); | |
1617 | else | |
1618 | __clear_bit(group - 1, nlk->groups); | |
1619 | netlink_update_subscriptions(&nlk->sk, subscriptions); | |
1620 | netlink_update_listeners(&nlk->sk); | |
1621 | } | |
1622 | ||
9a4595bc | 1623 | static int netlink_setsockopt(struct socket *sock, int level, int optname, |
a7b75c5a | 1624 | sockptr_t optval, unsigned int optlen) |
9a4595bc PM |
1625 | { |
1626 | struct sock *sk = sock->sk; | |
1627 | struct netlink_sock *nlk = nlk_sk(sk); | |
eb496534 JB |
1628 | unsigned int val = 0; |
1629 | int err; | |
9a4595bc PM |
1630 | |
1631 | if (level != SOL_NETLINK) | |
1632 | return -ENOPROTOOPT; | |
1633 | ||
d1b4c689 | 1634 | if (optlen >= sizeof(int) && |
a7b75c5a | 1635 | copy_from_sockptr(&val, optval, sizeof(val))) |
9a4595bc PM |
1636 | return -EFAULT; |
1637 | ||
1638 | switch (optname) { | |
1639 | case NETLINK_PKTINFO: | |
1640 | if (val) | |
cc3a572f | 1641 | nlk->flags |= NETLINK_F_RECV_PKTINFO; |
9a4595bc | 1642 | else |
cc3a572f | 1643 | nlk->flags &= ~NETLINK_F_RECV_PKTINFO; |
9a4595bc PM |
1644 | err = 0; |
1645 | break; | |
1646 | case NETLINK_ADD_MEMBERSHIP: | |
1647 | case NETLINK_DROP_MEMBERSHIP: { | |
5187cd05 | 1648 | if (!netlink_allowed(sock, NL_CFG_F_NONROOT_RECV)) |
9a4595bc | 1649 | return -EPERM; |
b4ff4f04 JB |
1650 | err = netlink_realloc_groups(sk); |
1651 | if (err) | |
1652 | return err; | |
9a4595bc PM |
1653 | if (!val || val - 1 >= nlk->ngroups) |
1654 | return -EINVAL; | |
7774d5e0 | 1655 | if (optname == NETLINK_ADD_MEMBERSHIP && nlk->netlink_bind) { |
023e2cfa | 1656 | err = nlk->netlink_bind(sock_net(sk), val); |
4f520900 RGB |
1657 | if (err) |
1658 | return err; | |
1659 | } | |
9a4595bc | 1660 | netlink_table_grab(); |
84659eb5 JB |
1661 | netlink_update_socket_mc(nlk, val, |
1662 | optname == NETLINK_ADD_MEMBERSHIP); | |
9a4595bc | 1663 | netlink_table_ungrab(); |
7774d5e0 | 1664 | if (optname == NETLINK_DROP_MEMBERSHIP && nlk->netlink_unbind) |
023e2cfa | 1665 | nlk->netlink_unbind(sock_net(sk), val); |
03292745 | 1666 | |
9a4595bc PM |
1667 | err = 0; |
1668 | break; | |
1669 | } | |
be0c22a4 PNA |
1670 | case NETLINK_BROADCAST_ERROR: |
1671 | if (val) | |
cc3a572f | 1672 | nlk->flags |= NETLINK_F_BROADCAST_SEND_ERROR; |
be0c22a4 | 1673 | else |
cc3a572f | 1674 | nlk->flags &= ~NETLINK_F_BROADCAST_SEND_ERROR; |
be0c22a4 PNA |
1675 | err = 0; |
1676 | break; | |
38938bfe PNA |
1677 | case NETLINK_NO_ENOBUFS: |
1678 | if (val) { | |
cc3a572f ND |
1679 | nlk->flags |= NETLINK_F_RECV_NO_ENOBUFS; |
1680 | clear_bit(NETLINK_S_CONGESTED, &nlk->state); | |
38938bfe | 1681 | wake_up_interruptible(&nlk->wait); |
658cb354 | 1682 | } else { |
cc3a572f | 1683 | nlk->flags &= ~NETLINK_F_RECV_NO_ENOBUFS; |
658cb354 | 1684 | } |
38938bfe PNA |
1685 | err = 0; |
1686 | break; | |
59324cf3 ND |
1687 | case NETLINK_LISTEN_ALL_NSID: |
1688 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_BROADCAST)) | |
1689 | return -EPERM; | |
1690 | ||
1691 | if (val) | |
1692 | nlk->flags |= NETLINK_F_LISTEN_ALL_NSID; | |
1693 | else | |
1694 | nlk->flags &= ~NETLINK_F_LISTEN_ALL_NSID; | |
1695 | err = 0; | |
1696 | break; | |
0a6a3a23 CR |
1697 | case NETLINK_CAP_ACK: |
1698 | if (val) | |
1699 | nlk->flags |= NETLINK_F_CAP_ACK; | |
1700 | else | |
1701 | nlk->flags &= ~NETLINK_F_CAP_ACK; | |
1702 | err = 0; | |
1703 | break; | |
2d4bc933 JB |
1704 | case NETLINK_EXT_ACK: |
1705 | if (val) | |
1706 | nlk->flags |= NETLINK_F_EXT_ACK; | |
1707 | else | |
1708 | nlk->flags &= ~NETLINK_F_EXT_ACK; | |
1709 | err = 0; | |
1710 | break; | |
d3e8869e | 1711 | case NETLINK_GET_STRICT_CHK: |
89d35528 DA |
1712 | if (val) |
1713 | nlk->flags |= NETLINK_F_STRICT_CHK; | |
1714 | else | |
1715 | nlk->flags &= ~NETLINK_F_STRICT_CHK; | |
1716 | err = 0; | |
1717 | break; | |
9a4595bc PM |
1718 | default: |
1719 | err = -ENOPROTOOPT; | |
1720 | } | |
1721 | return err; | |
1722 | } | |
1723 | ||
1724 | static int netlink_getsockopt(struct socket *sock, int level, int optname, | |
746fac4d | 1725 | char __user *optval, int __user *optlen) |
9a4595bc PM |
1726 | { |
1727 | struct sock *sk = sock->sk; | |
1728 | struct netlink_sock *nlk = nlk_sk(sk); | |
1729 | int len, val, err; | |
1730 | ||
1731 | if (level != SOL_NETLINK) | |
1732 | return -ENOPROTOOPT; | |
1733 | ||
1734 | if (get_user(len, optlen)) | |
1735 | return -EFAULT; | |
1736 | if (len < 0) | |
1737 | return -EINVAL; | |
1738 | ||
1739 | switch (optname) { | |
1740 | case NETLINK_PKTINFO: | |
1741 | if (len < sizeof(int)) | |
1742 | return -EINVAL; | |
1743 | len = sizeof(int); | |
cc3a572f | 1744 | val = nlk->flags & NETLINK_F_RECV_PKTINFO ? 1 : 0; |
a27b58fe HC |
1745 | if (put_user(len, optlen) || |
1746 | put_user(val, optval)) | |
1747 | return -EFAULT; | |
9a4595bc PM |
1748 | err = 0; |
1749 | break; | |
be0c22a4 PNA |
1750 | case NETLINK_BROADCAST_ERROR: |
1751 | if (len < sizeof(int)) | |
1752 | return -EINVAL; | |
1753 | len = sizeof(int); | |
cc3a572f | 1754 | val = nlk->flags & NETLINK_F_BROADCAST_SEND_ERROR ? 1 : 0; |
be0c22a4 PNA |
1755 | if (put_user(len, optlen) || |
1756 | put_user(val, optval)) | |
1757 | return -EFAULT; | |
1758 | err = 0; | |
1759 | break; | |
38938bfe PNA |
1760 | case NETLINK_NO_ENOBUFS: |
1761 | if (len < sizeof(int)) | |
1762 | return -EINVAL; | |
1763 | len = sizeof(int); | |
cc3a572f | 1764 | val = nlk->flags & NETLINK_F_RECV_NO_ENOBUFS ? 1 : 0; |
38938bfe PNA |
1765 | if (put_user(len, optlen) || |
1766 | put_user(val, optval)) | |
1767 | return -EFAULT; | |
1768 | err = 0; | |
1769 | break; | |
b42be38b DH |
1770 | case NETLINK_LIST_MEMBERSHIPS: { |
1771 | int pos, idx, shift; | |
1772 | ||
1773 | err = 0; | |
47191d65 | 1774 | netlink_lock_table(); |
b42be38b DH |
1775 | for (pos = 0; pos * 8 < nlk->ngroups; pos += sizeof(u32)) { |
1776 | if (len - pos < sizeof(u32)) | |
1777 | break; | |
1778 | ||
1779 | idx = pos / sizeof(unsigned long); | |
1780 | shift = (pos % sizeof(unsigned long)) * 8; | |
1781 | if (put_user((u32)(nlk->groups[idx] >> shift), | |
1782 | (u32 __user *)(optval + pos))) { | |
1783 | err = -EFAULT; | |
1784 | break; | |
1785 | } | |
1786 | } | |
1787 | if (put_user(ALIGN(nlk->ngroups / 8, sizeof(u32)), optlen)) | |
1788 | err = -EFAULT; | |
47191d65 | 1789 | netlink_unlock_table(); |
b42be38b DH |
1790 | break; |
1791 | } | |
0a6a3a23 CR |
1792 | case NETLINK_CAP_ACK: |
1793 | if (len < sizeof(int)) | |
1794 | return -EINVAL; | |
1795 | len = sizeof(int); | |
1796 | val = nlk->flags & NETLINK_F_CAP_ACK ? 1 : 0; | |
1797 | if (put_user(len, optlen) || | |
1798 | put_user(val, optval)) | |
1799 | return -EFAULT; | |
1800 | err = 0; | |
1801 | break; | |
2d4bc933 JB |
1802 | case NETLINK_EXT_ACK: |
1803 | if (len < sizeof(int)) | |
1804 | return -EINVAL; | |
1805 | len = sizeof(int); | |
1806 | val = nlk->flags & NETLINK_F_EXT_ACK ? 1 : 0; | |
1807 | if (put_user(len, optlen) || put_user(val, optval)) | |
1808 | return -EFAULT; | |
1809 | err = 0; | |
1810 | break; | |
d3e8869e | 1811 | case NETLINK_GET_STRICT_CHK: |
89d35528 DA |
1812 | if (len < sizeof(int)) |
1813 | return -EINVAL; | |
1814 | len = sizeof(int); | |
1815 | val = nlk->flags & NETLINK_F_STRICT_CHK ? 1 : 0; | |
1816 | if (put_user(len, optlen) || put_user(val, optval)) | |
1817 | return -EFAULT; | |
1818 | err = 0; | |
1819 | break; | |
9a4595bc PM |
1820 | default: |
1821 | err = -ENOPROTOOPT; | |
1822 | } | |
1823 | return err; | |
1824 | } | |
1825 | ||
1826 | static void netlink_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb) | |
1827 | { | |
1828 | struct nl_pktinfo info; | |
1829 | ||
1830 | info.group = NETLINK_CB(skb).dst_group; | |
1831 | put_cmsg(msg, SOL_NETLINK, NETLINK_PKTINFO, sizeof(info), &info); | |
1832 | } | |
1833 | ||
59324cf3 ND |
1834 | static void netlink_cmsg_listen_all_nsid(struct sock *sk, struct msghdr *msg, |
1835 | struct sk_buff *skb) | |
1836 | { | |
1837 | if (!NETLINK_CB(skb).nsid_is_set) | |
1838 | return; | |
1839 | ||
1840 | put_cmsg(msg, SOL_NETLINK, NETLINK_LISTEN_ALL_NSID, sizeof(int), | |
1841 | &NETLINK_CB(skb).nsid); | |
1842 | } | |
1843 | ||
1b784140 | 1844 | static int netlink_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) |
1da177e4 | 1845 | { |
1da177e4 LT |
1846 | struct sock *sk = sock->sk; |
1847 | struct netlink_sock *nlk = nlk_sk(sk); | |
342dfc30 | 1848 | DECLARE_SOCKADDR(struct sockaddr_nl *, addr, msg->msg_name); |
15e47304 | 1849 | u32 dst_portid; |
d629b836 | 1850 | u32 dst_group; |
1da177e4 LT |
1851 | struct sk_buff *skb; |
1852 | int err; | |
1853 | struct scm_cookie scm; | |
2d7a85f4 | 1854 | u32 netlink_skb_flags = 0; |
1da177e4 | 1855 | |
4d11af5d | 1856 | if (msg->msg_flags & MSG_OOB) |
1da177e4 LT |
1857 | return -EOPNOTSUPP; |
1858 | ||
7cc05662 | 1859 | err = scm_send(sock, msg, &scm, true); |
1da177e4 LT |
1860 | if (err < 0) |
1861 | return err; | |
1862 | ||
1863 | if (msg->msg_namelen) { | |
b47030c7 | 1864 | err = -EINVAL; |
6091f09c ED |
1865 | if (msg->msg_namelen < sizeof(struct sockaddr_nl)) |
1866 | goto out; | |
1da177e4 | 1867 | if (addr->nl_family != AF_NETLINK) |
b47030c7 | 1868 | goto out; |
15e47304 | 1869 | dst_portid = addr->nl_pid; |
d629b836 | 1870 | dst_group = ffs(addr->nl_groups); |
b47030c7 | 1871 | err = -EPERM; |
15e47304 | 1872 | if ((dst_group || dst_portid) && |
5187cd05 | 1873 | !netlink_allowed(sock, NL_CFG_F_NONROOT_SEND)) |
b47030c7 | 1874 | goto out; |
2d7a85f4 | 1875 | netlink_skb_flags |= NETLINK_SKB_DST; |
1da177e4 | 1876 | } else { |
15e47304 | 1877 | dst_portid = nlk->dst_portid; |
d629b836 | 1878 | dst_group = nlk->dst_group; |
1da177e4 LT |
1879 | } |
1880 | ||
da314c99 | 1881 | if (!nlk->bound) { |
1da177e4 LT |
1882 | err = netlink_autobind(sock); |
1883 | if (err) | |
1884 | goto out; | |
da314c99 HX |
1885 | } else { |
1886 | /* Ensure nlk is hashed and visible. */ | |
1887 | smp_rmb(); | |
1da177e4 LT |
1888 | } |
1889 | ||
1890 | err = -EMSGSIZE; | |
1891 | if (len > sk->sk_sndbuf - 32) | |
1892 | goto out; | |
1893 | err = -ENOBUFS; | |
3a36515f | 1894 | skb = netlink_alloc_large_skb(len, dst_group); |
6ac552fd | 1895 | if (skb == NULL) |
1da177e4 LT |
1896 | goto out; |
1897 | ||
15e47304 | 1898 | NETLINK_CB(skb).portid = nlk->portid; |
d629b836 | 1899 | NETLINK_CB(skb).dst_group = dst_group; |
7cc05662 | 1900 | NETLINK_CB(skb).creds = scm.creds; |
2d7a85f4 | 1901 | NETLINK_CB(skb).flags = netlink_skb_flags; |
1da177e4 | 1902 | |
1da177e4 | 1903 | err = -EFAULT; |
6ce8e9ce | 1904 | if (memcpy_from_msg(skb_put(skb, len), msg, len)) { |
1da177e4 LT |
1905 | kfree_skb(skb); |
1906 | goto out; | |
1907 | } | |
1908 | ||
1909 | err = security_netlink_send(sk, skb); | |
1910 | if (err) { | |
1911 | kfree_skb(skb); | |
1912 | goto out; | |
1913 | } | |
1914 | ||
d629b836 | 1915 | if (dst_group) { |
63354797 | 1916 | refcount_inc(&skb->users); |
15e47304 | 1917 | netlink_broadcast(sk, skb, dst_portid, dst_group, GFP_KERNEL); |
1da177e4 | 1918 | } |
4d11af5d | 1919 | err = netlink_unicast(sk, skb, dst_portid, msg->msg_flags & MSG_DONTWAIT); |
1da177e4 LT |
1920 | |
1921 | out: | |
7cc05662 | 1922 | scm_destroy(&scm); |
1da177e4 LT |
1923 | return err; |
1924 | } | |
1925 | ||
1b784140 | 1926 | static int netlink_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, |
1da177e4 LT |
1927 | int flags) |
1928 | { | |
1da177e4 LT |
1929 | struct scm_cookie scm; |
1930 | struct sock *sk = sock->sk; | |
1931 | struct netlink_sock *nlk = nlk_sk(sk); | |
4d11af5d | 1932 | int noblock = flags & MSG_DONTWAIT; |
1da177e4 | 1933 | size_t copied; |
68d6ac6d | 1934 | struct sk_buff *skb, *data_skb; |
b44d211e | 1935 | int err, ret; |
1da177e4 | 1936 | |
4d11af5d | 1937 | if (flags & MSG_OOB) |
1da177e4 LT |
1938 | return -EOPNOTSUPP; |
1939 | ||
1940 | copied = 0; | |
1941 | ||
6ac552fd PM |
1942 | skb = skb_recv_datagram(sk, flags, noblock, &err); |
1943 | if (skb == NULL) | |
1da177e4 LT |
1944 | goto out; |
1945 | ||
68d6ac6d JB |
1946 | data_skb = skb; |
1947 | ||
1dacc76d JB |
1948 | #ifdef CONFIG_COMPAT_NETLINK_MESSAGES |
1949 | if (unlikely(skb_shinfo(skb)->frag_list)) { | |
1dacc76d | 1950 | /* |
68d6ac6d JB |
1951 | * If this skb has a frag_list, then here that means that we |
1952 | * will have to use the frag_list skb's data for compat tasks | |
1953 | * and the regular skb's data for normal (non-compat) tasks. | |
1dacc76d | 1954 | * |
68d6ac6d JB |
1955 | * If we need to send the compat skb, assign it to the |
1956 | * 'data_skb' variable so that it will be used below for data | |
1957 | * copying. We keep 'skb' for everything else, including | |
1958 | * freeing both later. | |
1dacc76d | 1959 | */ |
68d6ac6d JB |
1960 | if (flags & MSG_CMSG_COMPAT) |
1961 | data_skb = skb_shinfo(skb)->frag_list; | |
1dacc76d JB |
1962 | } |
1963 | #endif | |
1964 | ||
9063e21f ED |
1965 | /* Record the max length of recvmsg() calls for future allocations */ |
1966 | nlk->max_recvmsg_len = max(nlk->max_recvmsg_len, len); | |
1967 | nlk->max_recvmsg_len = min_t(size_t, nlk->max_recvmsg_len, | |
d35c99ff | 1968 | SKB_WITH_OVERHEAD(32768)); |
9063e21f | 1969 | |
68d6ac6d | 1970 | copied = data_skb->len; |
1da177e4 LT |
1971 | if (len < copied) { |
1972 | msg->msg_flags |= MSG_TRUNC; | |
1973 | copied = len; | |
1974 | } | |
1975 | ||
68d6ac6d | 1976 | skb_reset_transport_header(data_skb); |
51f3d02b | 1977 | err = skb_copy_datagram_msg(data_skb, 0, msg, copied); |
1da177e4 LT |
1978 | |
1979 | if (msg->msg_name) { | |
342dfc30 | 1980 | DECLARE_SOCKADDR(struct sockaddr_nl *, addr, msg->msg_name); |
1da177e4 LT |
1981 | addr->nl_family = AF_NETLINK; |
1982 | addr->nl_pad = 0; | |
15e47304 | 1983 | addr->nl_pid = NETLINK_CB(skb).portid; |
d629b836 | 1984 | addr->nl_groups = netlink_group_mask(NETLINK_CB(skb).dst_group); |
1da177e4 LT |
1985 | msg->msg_namelen = sizeof(*addr); |
1986 | } | |
1987 | ||
cc3a572f | 1988 | if (nlk->flags & NETLINK_F_RECV_PKTINFO) |
cc9a06cd | 1989 | netlink_cmsg_recv_pktinfo(msg, skb); |
59324cf3 ND |
1990 | if (nlk->flags & NETLINK_F_LISTEN_ALL_NSID) |
1991 | netlink_cmsg_listen_all_nsid(sk, msg, skb); | |
cc9a06cd | 1992 | |
7cc05662 CH |
1993 | memset(&scm, 0, sizeof(scm)); |
1994 | scm.creds = *NETLINK_CREDS(skb); | |
188ccb55 | 1995 | if (flags & MSG_TRUNC) |
68d6ac6d | 1996 | copied = data_skb->len; |
daa3766e | 1997 | |
1da177e4 LT |
1998 | skb_free_datagram(sk, skb); |
1999 | ||
16b304f3 PS |
2000 | if (nlk->cb_running && |
2001 | atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) { | |
b44d211e AV |
2002 | ret = netlink_dump(sk); |
2003 | if (ret) { | |
ac30ef83 | 2004 | sk->sk_err = -ret; |
b44d211e AV |
2005 | sk->sk_error_report(sk); |
2006 | } | |
2007 | } | |
1da177e4 | 2008 | |
7cc05662 | 2009 | scm_recv(sock, msg, &scm, flags); |
1da177e4 LT |
2010 | out: |
2011 | netlink_rcv_wake(sk); | |
2012 | return err ? : copied; | |
2013 | } | |
2014 | ||
676d2369 | 2015 | static void netlink_data_ready(struct sock *sk) |
1da177e4 | 2016 | { |
cd40b7d3 | 2017 | BUG(); |
1da177e4 LT |
2018 | } |
2019 | ||
2020 | /* | |
746fac4d | 2021 | * We export these functions to other modules. They provide a |
1da177e4 LT |
2022 | * complete set of kernel non-blocking support for message |
2023 | * queueing. | |
2024 | */ | |
2025 | ||
2026 | struct sock * | |
9f00d977 PNA |
2027 | __netlink_kernel_create(struct net *net, int unit, struct module *module, |
2028 | struct netlink_kernel_cfg *cfg) | |
1da177e4 LT |
2029 | { |
2030 | struct socket *sock; | |
2031 | struct sock *sk; | |
77247bbb | 2032 | struct netlink_sock *nlk; |
5c398dc8 | 2033 | struct listeners *listeners = NULL; |
a31f2d17 PNA |
2034 | struct mutex *cb_mutex = cfg ? cfg->cb_mutex : NULL; |
2035 | unsigned int groups; | |
1da177e4 | 2036 | |
fab2caf6 | 2037 | BUG_ON(!nl_table); |
1da177e4 | 2038 | |
6ac552fd | 2039 | if (unit < 0 || unit >= MAX_LINKS) |
1da177e4 LT |
2040 | return NULL; |
2041 | ||
2042 | if (sock_create_lite(PF_NETLINK, SOCK_DGRAM, unit, &sock)) | |
2043 | return NULL; | |
13d3078e EB |
2044 | |
2045 | if (__netlink_create(net, sock, cb_mutex, unit, 1) < 0) | |
23fe1866 PE |
2046 | goto out_sock_release_nosk; |
2047 | ||
2048 | sk = sock->sk; | |
4fdb3bb7 | 2049 | |
a31f2d17 | 2050 | if (!cfg || cfg->groups < 32) |
4277a083 | 2051 | groups = 32; |
a31f2d17 PNA |
2052 | else |
2053 | groups = cfg->groups; | |
4277a083 | 2054 | |
5c398dc8 | 2055 | listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL); |
4277a083 PM |
2056 | if (!listeners) |
2057 | goto out_sock_release; | |
2058 | ||
1da177e4 | 2059 | sk->sk_data_ready = netlink_data_ready; |
a31f2d17 PNA |
2060 | if (cfg && cfg->input) |
2061 | nlk_sk(sk)->netlink_rcv = cfg->input; | |
1da177e4 | 2062 | |
8ea65f4a | 2063 | if (netlink_insert(sk, 0)) |
77247bbb | 2064 | goto out_sock_release; |
4fdb3bb7 | 2065 | |
77247bbb | 2066 | nlk = nlk_sk(sk); |
cc3a572f | 2067 | nlk->flags |= NETLINK_F_KERNEL_SOCKET; |
4fdb3bb7 | 2068 | |
4fdb3bb7 | 2069 | netlink_table_grab(); |
b4b51029 EB |
2070 | if (!nl_table[unit].registered) { |
2071 | nl_table[unit].groups = groups; | |
5c398dc8 | 2072 | rcu_assign_pointer(nl_table[unit].listeners, listeners); |
b4b51029 EB |
2073 | nl_table[unit].cb_mutex = cb_mutex; |
2074 | nl_table[unit].module = module; | |
9785e10a PNA |
2075 | if (cfg) { |
2076 | nl_table[unit].bind = cfg->bind; | |
6251edd9 | 2077 | nl_table[unit].unbind = cfg->unbind; |
9785e10a | 2078 | nl_table[unit].flags = cfg->flags; |
da12c90e G |
2079 | if (cfg->compare) |
2080 | nl_table[unit].compare = cfg->compare; | |
9785e10a | 2081 | } |
b4b51029 | 2082 | nl_table[unit].registered = 1; |
f937f1f4 JJ |
2083 | } else { |
2084 | kfree(listeners); | |
869e58f8 | 2085 | nl_table[unit].registered++; |
b4b51029 | 2086 | } |
4fdb3bb7 | 2087 | netlink_table_ungrab(); |
77247bbb PM |
2088 | return sk; |
2089 | ||
4fdb3bb7 | 2090 | out_sock_release: |
4277a083 | 2091 | kfree(listeners); |
9dfbec1f | 2092 | netlink_kernel_release(sk); |
23fe1866 PE |
2093 | return NULL; |
2094 | ||
2095 | out_sock_release_nosk: | |
4fdb3bb7 | 2096 | sock_release(sock); |
77247bbb | 2097 | return NULL; |
1da177e4 | 2098 | } |
9f00d977 | 2099 | EXPORT_SYMBOL(__netlink_kernel_create); |
b7c6ba6e DL |
2100 | |
2101 | void | |
2102 | netlink_kernel_release(struct sock *sk) | |
2103 | { | |
13d3078e EB |
2104 | if (sk == NULL || sk->sk_socket == NULL) |
2105 | return; | |
2106 | ||
2107 | sock_release(sk->sk_socket); | |
b7c6ba6e DL |
2108 | } |
2109 | EXPORT_SYMBOL(netlink_kernel_release); | |
2110 | ||
d136f1bd | 2111 | int __netlink_change_ngroups(struct sock *sk, unsigned int groups) |
b4ff4f04 | 2112 | { |
5c398dc8 | 2113 | struct listeners *new, *old; |
b4ff4f04 | 2114 | struct netlink_table *tbl = &nl_table[sk->sk_protocol]; |
b4ff4f04 JB |
2115 | |
2116 | if (groups < 32) | |
2117 | groups = 32; | |
2118 | ||
b4ff4f04 | 2119 | if (NLGRPSZ(tbl->groups) < NLGRPSZ(groups)) { |
5c398dc8 ED |
2120 | new = kzalloc(sizeof(*new) + NLGRPSZ(groups), GFP_ATOMIC); |
2121 | if (!new) | |
d136f1bd | 2122 | return -ENOMEM; |
6d772ac5 | 2123 | old = nl_deref_protected(tbl->listeners); |
5c398dc8 ED |
2124 | memcpy(new->masks, old->masks, NLGRPSZ(tbl->groups)); |
2125 | rcu_assign_pointer(tbl->listeners, new); | |
2126 | ||
37b6b935 | 2127 | kfree_rcu(old, rcu); |
b4ff4f04 JB |
2128 | } |
2129 | tbl->groups = groups; | |
2130 | ||
d136f1bd JB |
2131 | return 0; |
2132 | } | |
2133 | ||
2134 | /** | |
2135 | * netlink_change_ngroups - change number of multicast groups | |
2136 | * | |
2137 | * This changes the number of multicast groups that are available | |
2138 | * on a certain netlink family. Note that it is not possible to | |
2139 | * change the number of groups to below 32. Also note that it does | |
2140 | * not implicitly call netlink_clear_multicast_users() when the | |
2141 | * number of groups is reduced. | |
2142 | * | |
2143 | * @sk: The kernel netlink socket, as returned by netlink_kernel_create(). | |
2144 | * @groups: The new number of groups. | |
2145 | */ | |
2146 | int netlink_change_ngroups(struct sock *sk, unsigned int groups) | |
2147 | { | |
2148 | int err; | |
2149 | ||
2150 | netlink_table_grab(); | |
2151 | err = __netlink_change_ngroups(sk, groups); | |
b4ff4f04 | 2152 | netlink_table_ungrab(); |
d136f1bd | 2153 | |
b4ff4f04 JB |
2154 | return err; |
2155 | } | |
b4ff4f04 | 2156 | |
b8273570 JB |
2157 | void __netlink_clear_multicast_users(struct sock *ksk, unsigned int group) |
2158 | { | |
2159 | struct sock *sk; | |
b8273570 JB |
2160 | struct netlink_table *tbl = &nl_table[ksk->sk_protocol]; |
2161 | ||
b67bfe0d | 2162 | sk_for_each_bound(sk, &tbl->mc_list) |
b8273570 JB |
2163 | netlink_update_socket_mc(nlk_sk(sk), group, 0); |
2164 | } | |
2165 | ||
a46621a3 | 2166 | struct nlmsghdr * |
15e47304 | 2167 | __nlmsg_put(struct sk_buff *skb, u32 portid, u32 seq, int type, int len, int flags) |
a46621a3 DV |
2168 | { |
2169 | struct nlmsghdr *nlh; | |
573ce260 | 2170 | int size = nlmsg_msg_size(len); |
a46621a3 | 2171 | |
4df864c1 | 2172 | nlh = skb_put(skb, NLMSG_ALIGN(size)); |
a46621a3 DV |
2173 | nlh->nlmsg_type = type; |
2174 | nlh->nlmsg_len = size; | |
2175 | nlh->nlmsg_flags = flags; | |
15e47304 | 2176 | nlh->nlmsg_pid = portid; |
a46621a3 DV |
2177 | nlh->nlmsg_seq = seq; |
2178 | if (!__builtin_constant_p(size) || NLMSG_ALIGN(size) - size != 0) | |
573ce260 | 2179 | memset(nlmsg_data(nlh) + len, 0, NLMSG_ALIGN(size) - size); |
a46621a3 DV |
2180 | return nlh; |
2181 | } | |
2182 | EXPORT_SYMBOL(__nlmsg_put); | |
2183 | ||
1da177e4 LT |
2184 | /* |
2185 | * It looks a bit ugly. | |
2186 | * It would be better to create kernel thread. | |
2187 | */ | |
2188 | ||
e11eb32d DS |
2189 | static int netlink_dump_done(struct netlink_sock *nlk, struct sk_buff *skb, |
2190 | struct netlink_callback *cb, | |
2191 | struct netlink_ext_ack *extack) | |
2192 | { | |
2193 | struct nlmsghdr *nlh; | |
2194 | ||
2195 | nlh = nlmsg_put_answer(skb, cb, NLMSG_DONE, sizeof(nlk->dump_done_errno), | |
2196 | NLM_F_MULTI | cb->answer_flags); | |
2197 | if (WARN_ON(!nlh)) | |
2198 | return -ENOBUFS; | |
2199 | ||
2200 | nl_dump_check_consistent(cb, nlh); | |
2201 | memcpy(nlmsg_data(nlh), &nlk->dump_done_errno, sizeof(nlk->dump_done_errno)); | |
2202 | ||
2203 | if (extack->_msg && nlk->flags & NETLINK_F_EXT_ACK) { | |
2204 | nlh->nlmsg_flags |= NLM_F_ACK_TLVS; | |
2205 | if (!nla_put_string(skb, NLMSGERR_ATTR_MSG, extack->_msg)) | |
2206 | nlmsg_end(skb, nlh); | |
2207 | } | |
2208 | ||
2209 | return 0; | |
2210 | } | |
2211 | ||
1da177e4 LT |
2212 | static int netlink_dump(struct sock *sk) |
2213 | { | |
2214 | struct netlink_sock *nlk = nlk_sk(sk); | |
4a19edb6 | 2215 | struct netlink_ext_ack extack = {}; |
1da177e4 | 2216 | struct netlink_callback *cb; |
c7ac8679 | 2217 | struct sk_buff *skb = NULL; |
92964c79 | 2218 | struct module *module; |
0642840b | 2219 | int err = -ENOBUFS; |
db65a3aa | 2220 | int alloc_min_size; |
c7ac8679 | 2221 | int alloc_size; |
1da177e4 | 2222 | |
af65bdfc | 2223 | mutex_lock(nlk->cb_mutex); |
16b304f3 | 2224 | if (!nlk->cb_running) { |
bf8b79e4 TG |
2225 | err = -EINVAL; |
2226 | goto errout_skb; | |
1da177e4 LT |
2227 | } |
2228 | ||
d1b4c689 | 2229 | if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) |
f9c22888 | 2230 | goto errout_skb; |
9063e21f ED |
2231 | |
2232 | /* NLMSG_GOODSIZE is small to avoid high order allocations being | |
2233 | * required, but it makes sense to _attempt_ a 16K bytes allocation | |
2234 | * to reduce number of system calls on dump operations, if user | |
2235 | * ever provided a big enough buffer. | |
2236 | */ | |
db65a3aa AR |
2237 | cb = &nlk->cb; |
2238 | alloc_min_size = max_t(int, cb->min_dump_alloc, NLMSG_GOODSIZE); | |
2239 | ||
2240 | if (alloc_min_size < nlk->max_recvmsg_len) { | |
2241 | alloc_size = nlk->max_recvmsg_len; | |
d35c99ff ED |
2242 | skb = alloc_skb(alloc_size, |
2243 | (GFP_KERNEL & ~__GFP_DIRECT_RECLAIM) | | |
2244 | __GFP_NOWARN | __GFP_NORETRY); | |
9063e21f | 2245 | } |
db65a3aa AR |
2246 | if (!skb) { |
2247 | alloc_size = alloc_min_size; | |
c5b0db32 | 2248 | skb = alloc_skb(alloc_size, GFP_KERNEL); |
db65a3aa | 2249 | } |
c7ac8679 | 2250 | if (!skb) |
c63d6ea3 | 2251 | goto errout_skb; |
db65a3aa AR |
2252 | |
2253 | /* Trim skb to allocated size. User is expected to provide buffer as | |
2254 | * large as max(min_dump_alloc, 16KiB (mac_recvmsg_len capped at | |
2255 | * netlink_recvmsg())). dump will pack as many smaller messages as | |
2256 | * could fit within the allocated skb. skb is typically allocated | |
2257 | * with larger space than required (could be as much as near 2x the | |
2258 | * requested size with align to next power of 2 approach). Allowing | |
2259 | * dump to use the excess space makes it difficult for a user to have a | |
2260 | * reasonable static buffer based on the expected largest dump of a | |
2261 | * single netdev. The outcome is MSG_TRUNC error. | |
2262 | */ | |
d1b4c689 | 2263 | skb_reserve(skb, skb_tailroom(skb) - alloc_size); |
f9c22888 | 2264 | netlink_skb_set_owner_r(skb, sk); |
c7ac8679 | 2265 | |
4a19edb6 DA |
2266 | if (nlk->dump_done_errno > 0) { |
2267 | cb->extack = &extack; | |
0642840b | 2268 | nlk->dump_done_errno = cb->dump(skb, cb); |
4a19edb6 DA |
2269 | cb->extack = NULL; |
2270 | } | |
1da177e4 | 2271 | |
0642840b JD |
2272 | if (nlk->dump_done_errno > 0 || |
2273 | skb_tailroom(skb) < nlmsg_total_size(sizeof(nlk->dump_done_errno))) { | |
af65bdfc | 2274 | mutex_unlock(nlk->cb_mutex); |
b1153f29 SH |
2275 | |
2276 | if (sk_filter(sk, skb)) | |
2277 | kfree_skb(skb); | |
4a7e7c2a ED |
2278 | else |
2279 | __netlink_sendskb(sk, skb); | |
1da177e4 LT |
2280 | return 0; |
2281 | } | |
2282 | ||
e11eb32d | 2283 | if (netlink_dump_done(nlk, skb, cb, &extack)) |
bf8b79e4 TG |
2284 | goto errout_skb; |
2285 | ||
e11eb32d DS |
2286 | #ifdef CONFIG_COMPAT_NETLINK_MESSAGES |
2287 | /* frag_list skb's data is used for compat tasks | |
2288 | * and the regular skb's data for normal (non-compat) tasks. | |
2289 | * See netlink_recvmsg(). | |
2290 | */ | |
2291 | if (unlikely(skb_shinfo(skb)->frag_list)) { | |
2292 | if (netlink_dump_done(nlk, skb_shinfo(skb)->frag_list, cb, &extack)) | |
2293 | goto errout_skb; | |
4a19edb6 | 2294 | } |
e11eb32d | 2295 | #endif |
4a19edb6 | 2296 | |
b1153f29 SH |
2297 | if (sk_filter(sk, skb)) |
2298 | kfree_skb(skb); | |
4a7e7c2a ED |
2299 | else |
2300 | __netlink_sendskb(sk, skb); | |
1da177e4 | 2301 | |
a8f74b22 TG |
2302 | if (cb->done) |
2303 | cb->done(cb); | |
1da177e4 | 2304 | |
16b304f3 | 2305 | nlk->cb_running = false; |
92964c79 HX |
2306 | module = cb->module; |
2307 | skb = cb->skb; | |
16b304f3 | 2308 | mutex_unlock(nlk->cb_mutex); |
92964c79 HX |
2309 | module_put(module); |
2310 | consume_skb(skb); | |
1da177e4 | 2311 | return 0; |
1797754e | 2312 | |
bf8b79e4 | 2313 | errout_skb: |
af65bdfc | 2314 | mutex_unlock(nlk->cb_mutex); |
bf8b79e4 | 2315 | kfree_skb(skb); |
bf8b79e4 | 2316 | return err; |
1da177e4 LT |
2317 | } |
2318 | ||
6dc878a8 G |
2319 | int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb, |
2320 | const struct nlmsghdr *nlh, | |
2321 | struct netlink_dump_control *control) | |
1da177e4 | 2322 | { |
89d35528 | 2323 | struct netlink_sock *nlk, *nlk2; |
1da177e4 LT |
2324 | struct netlink_callback *cb; |
2325 | struct sock *sk; | |
b44d211e | 2326 | int ret; |
1da177e4 | 2327 | |
63354797 | 2328 | refcount_inc(&skb->users); |
f9c22888 | 2329 | |
15e47304 | 2330 | sk = netlink_lookup(sock_net(ssk), ssk->sk_protocol, NETLINK_CB(skb).portid); |
1da177e4 | 2331 | if (sk == NULL) { |
16b304f3 PS |
2332 | ret = -ECONNREFUSED; |
2333 | goto error_free; | |
1da177e4 | 2334 | } |
6dc878a8 | 2335 | |
16b304f3 | 2336 | nlk = nlk_sk(sk); |
af65bdfc | 2337 | mutex_lock(nlk->cb_mutex); |
6dc878a8 | 2338 | /* A dump is in progress... */ |
16b304f3 | 2339 | if (nlk->cb_running) { |
6dc878a8 | 2340 | ret = -EBUSY; |
16b304f3 | 2341 | goto error_unlock; |
1da177e4 | 2342 | } |
6dc878a8 | 2343 | /* add reference of module which cb->dump belongs to */ |
16b304f3 | 2344 | if (!try_module_get(control->module)) { |
6dc878a8 | 2345 | ret = -EPROTONOSUPPORT; |
16b304f3 | 2346 | goto error_unlock; |
6dc878a8 G |
2347 | } |
2348 | ||
16b304f3 PS |
2349 | cb = &nlk->cb; |
2350 | memset(cb, 0, sizeof(*cb)); | |
2351 | cb->dump = control->dump; | |
2352 | cb->done = control->done; | |
2353 | cb->nlh = nlh; | |
2354 | cb->data = control->data; | |
2355 | cb->module = control->module; | |
2356 | cb->min_dump_alloc = control->min_dump_alloc; | |
2357 | cb->skb = skb; | |
2358 | ||
89d35528 DA |
2359 | nlk2 = nlk_sk(NETLINK_CB(skb).sk); |
2360 | cb->strict_check = !!(nlk2->flags & NETLINK_F_STRICT_CHK); | |
2361 | ||
3730cf4d FW |
2362 | if (control->start) { |
2363 | ret = control->start(cb); | |
41c87425 | 2364 | if (ret) |
b87b6194 | 2365 | goto error_put; |
41c87425 JD |
2366 | } |
2367 | ||
16b304f3 | 2368 | nlk->cb_running = true; |
0642840b | 2369 | nlk->dump_done_errno = INT_MAX; |
16b304f3 | 2370 | |
af65bdfc | 2371 | mutex_unlock(nlk->cb_mutex); |
1da177e4 | 2372 | |
41c87425 | 2373 | ret = netlink_dump(sk); |
fc9e50f5 | 2374 | |
1da177e4 | 2375 | sock_put(sk); |
5c58298c | 2376 | |
b44d211e AV |
2377 | if (ret) |
2378 | return ret; | |
2379 | ||
5c58298c DL |
2380 | /* We successfully started a dump, by returning -EINTR we |
2381 | * signal not to send ACK even if it was requested. | |
2382 | */ | |
2383 | return -EINTR; | |
16b304f3 | 2384 | |
b87b6194 JD |
2385 | error_put: |
2386 | module_put(control->module); | |
16b304f3 PS |
2387 | error_unlock: |
2388 | sock_put(sk); | |
2389 | mutex_unlock(nlk->cb_mutex); | |
2390 | error_free: | |
2391 | kfree_skb(skb); | |
2392 | return ret; | |
1da177e4 | 2393 | } |
6dc878a8 | 2394 | EXPORT_SYMBOL(__netlink_dump_start); |
1da177e4 | 2395 | |
2d4bc933 JB |
2396 | void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err, |
2397 | const struct netlink_ext_ack *extack) | |
1da177e4 LT |
2398 | { |
2399 | struct sk_buff *skb; | |
2400 | struct nlmsghdr *rep; | |
2401 | struct nlmsgerr *errmsg; | |
339bf98f | 2402 | size_t payload = sizeof(*errmsg); |
2d4bc933 | 2403 | size_t tlvlen = 0; |
0a6a3a23 | 2404 | struct netlink_sock *nlk = nlk_sk(NETLINK_CB(in_skb).sk); |
2d4bc933 | 2405 | unsigned int flags = 0; |
48044eb4 | 2406 | bool nlk_has_extack = nlk->flags & NETLINK_F_EXT_ACK; |
1da177e4 | 2407 | |
0a6a3a23 | 2408 | /* Error messages get the original request appened, unless the user |
2d4bc933 JB |
2409 | * requests to cap the error message, and get extra error data if |
2410 | * requested. | |
0a6a3a23 | 2411 | */ |
4f6265d4 DA |
2412 | if (nlk_has_extack && extack && extack->_msg) |
2413 | tlvlen += nla_total_size(strlen(extack->_msg) + 1); | |
2414 | ||
fe2a31d7 MK |
2415 | if (err && !(nlk->flags & NETLINK_F_CAP_ACK)) |
2416 | payload += nlmsg_len(nlh); | |
2417 | else | |
2d4bc933 | 2418 | flags |= NLM_F_CAPPED; |
fe2a31d7 MK |
2419 | if (err && nlk_has_extack && extack && extack->bad_attr) |
2420 | tlvlen += nla_total_size(sizeof(u32)); | |
2421 | if (nlk_has_extack && extack && extack->cookie_len) | |
2422 | tlvlen += nla_total_size(extack->cookie_len); | |
44f3625b JB |
2423 | if (err && nlk_has_extack && extack && extack->policy) |
2424 | tlvlen += netlink_policy_dump_attr_size_estimate(extack->policy); | |
1da177e4 | 2425 | |
2d4bc933 JB |
2426 | if (tlvlen) |
2427 | flags |= NLM_F_ACK_TLVS; | |
2428 | ||
2429 | skb = nlmsg_new(payload + tlvlen, GFP_KERNEL); | |
1da177e4 | 2430 | if (!skb) { |
a2084f56 JB |
2431 | NETLINK_CB(in_skb).sk->sk_err = ENOBUFS; |
2432 | NETLINK_CB(in_skb).sk->sk_error_report(NETLINK_CB(in_skb).sk); | |
1da177e4 LT |
2433 | return; |
2434 | } | |
2435 | ||
15e47304 | 2436 | rep = __nlmsg_put(skb, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, |
2d4bc933 | 2437 | NLMSG_ERROR, payload, flags); |
bf8b79e4 | 2438 | errmsg = nlmsg_data(rep); |
1da177e4 | 2439 | errmsg->error = err; |
0a6a3a23 | 2440 | memcpy(&errmsg->msg, nlh, payload > sizeof(*errmsg) ? nlh->nlmsg_len : sizeof(*nlh)); |
2d4bc933 | 2441 | |
48044eb4 | 2442 | if (nlk_has_extack && extack) { |
4f6265d4 DA |
2443 | if (extack->_msg) { |
2444 | WARN_ON(nla_put_string(skb, NLMSGERR_ATTR_MSG, | |
2445 | extack->_msg)); | |
2446 | } | |
fe2a31d7 MK |
2447 | if (err && extack->bad_attr && |
2448 | !WARN_ON((u8 *)extack->bad_attr < in_skb->data || | |
2449 | (u8 *)extack->bad_attr >= in_skb->data + | |
2450 | in_skb->len)) | |
2451 | WARN_ON(nla_put_u32(skb, NLMSGERR_ATTR_OFFS, | |
2452 | (u8 *)extack->bad_attr - | |
2453 | (u8 *)nlh)); | |
2454 | if (extack->cookie_len) | |
2455 | WARN_ON(nla_put(skb, NLMSGERR_ATTR_COOKIE, | |
2456 | extack->cookie_len, extack->cookie)); | |
44f3625b JB |
2457 | if (extack->policy) |
2458 | netlink_policy_dump_write_attr(skb, extack->policy, | |
2459 | NLMSGERR_ATTR_POLICY); | |
2d4bc933 JB |
2460 | } |
2461 | ||
2462 | nlmsg_end(skb, rep); | |
2463 | ||
15e47304 | 2464 | netlink_unicast(in_skb->sk, skb, NETLINK_CB(in_skb).portid, MSG_DONTWAIT); |
1da177e4 | 2465 | } |
6ac552fd | 2466 | EXPORT_SYMBOL(netlink_ack); |
1da177e4 | 2467 | |
cd40b7d3 | 2468 | int netlink_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *, |
2d4bc933 JB |
2469 | struct nlmsghdr *, |
2470 | struct netlink_ext_ack *)) | |
82ace47a | 2471 | { |
cbbdf843 | 2472 | struct netlink_ext_ack extack; |
82ace47a TG |
2473 | struct nlmsghdr *nlh; |
2474 | int err; | |
2475 | ||
2476 | while (skb->len >= nlmsg_total_size(0)) { | |
cd40b7d3 DL |
2477 | int msglen; |
2478 | ||
cd443f1e | 2479 | memset(&extack, 0, sizeof(extack)); |
b529ccf2 | 2480 | nlh = nlmsg_hdr(skb); |
d35b6856 | 2481 | err = 0; |
82ace47a | 2482 | |
ad8e4b75 | 2483 | if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len) |
82ace47a TG |
2484 | return 0; |
2485 | ||
d35b6856 TG |
2486 | /* Only requests are handled by the kernel */ |
2487 | if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) | |
5c58298c | 2488 | goto ack; |
45e7ae7f TG |
2489 | |
2490 | /* Skip control messages */ | |
2491 | if (nlh->nlmsg_type < NLMSG_MIN_TYPE) | |
5c58298c | 2492 | goto ack; |
d35b6856 | 2493 | |
2d4bc933 | 2494 | err = cb(skb, nlh, &extack); |
5c58298c DL |
2495 | if (err == -EINTR) |
2496 | goto skip; | |
2497 | ||
2498 | ack: | |
d35b6856 | 2499 | if (nlh->nlmsg_flags & NLM_F_ACK || err) |
2d4bc933 | 2500 | netlink_ack(skb, nlh, err, &extack); |
82ace47a | 2501 | |
5c58298c | 2502 | skip: |
6ac552fd | 2503 | msglen = NLMSG_ALIGN(nlh->nlmsg_len); |
cd40b7d3 DL |
2504 | if (msglen > skb->len) |
2505 | msglen = skb->len; | |
2506 | skb_pull(skb, msglen); | |
82ace47a TG |
2507 | } |
2508 | ||
2509 | return 0; | |
2510 | } | |
6ac552fd | 2511 | EXPORT_SYMBOL(netlink_rcv_skb); |
82ace47a | 2512 | |
d387f6ad TG |
2513 | /** |
2514 | * nlmsg_notify - send a notification netlink message | |
2515 | * @sk: netlink socket to use | |
2516 | * @skb: notification message | |
15e47304 | 2517 | * @portid: destination netlink portid for reports or 0 |
d387f6ad TG |
2518 | * @group: destination multicast group or 0 |
2519 | * @report: 1 to report back, 0 to disable | |
2520 | * @flags: allocation flags | |
2521 | */ | |
15e47304 | 2522 | int nlmsg_notify(struct sock *sk, struct sk_buff *skb, u32 portid, |
d387f6ad TG |
2523 | unsigned int group, int report, gfp_t flags) |
2524 | { | |
2525 | int err = 0; | |
2526 | ||
2527 | if (group) { | |
15e47304 | 2528 | int exclude_portid = 0; |
d387f6ad TG |
2529 | |
2530 | if (report) { | |
63354797 | 2531 | refcount_inc(&skb->users); |
15e47304 | 2532 | exclude_portid = portid; |
d387f6ad TG |
2533 | } |
2534 | ||
1ce85fe4 PNA |
2535 | /* errors reported via destination sk->sk_err, but propagate |
2536 | * delivery errors if NETLINK_BROADCAST_ERROR flag is set */ | |
15e47304 | 2537 | err = nlmsg_multicast(sk, skb, exclude_portid, group, flags); |
d387f6ad TG |
2538 | } |
2539 | ||
1ce85fe4 PNA |
2540 | if (report) { |
2541 | int err2; | |
2542 | ||
15e47304 | 2543 | err2 = nlmsg_unicast(sk, skb, portid); |
1ce85fe4 PNA |
2544 | if (!err || err == -ESRCH) |
2545 | err = err2; | |
2546 | } | |
d387f6ad TG |
2547 | |
2548 | return err; | |
2549 | } | |
6ac552fd | 2550 | EXPORT_SYMBOL(nlmsg_notify); |
d387f6ad | 2551 | |
1da177e4 LT |
2552 | #ifdef CONFIG_PROC_FS |
2553 | struct nl_seq_iter { | |
e372c414 | 2554 | struct seq_net_private p; |
56d28b1e | 2555 | struct rhashtable_iter hti; |
1da177e4 | 2556 | int link; |
1da177e4 LT |
2557 | }; |
2558 | ||
abf9979f | 2559 | static void netlink_walk_start(struct nl_seq_iter *iter) |
1da177e4 | 2560 | { |
6c4128f6 | 2561 | rhashtable_walk_enter(&nl_table[iter->link].hash, &iter->hti); |
97a6ec4a | 2562 | rhashtable_walk_start(&iter->hti); |
1da177e4 LT |
2563 | } |
2564 | ||
56d28b1e | 2565 | static void netlink_walk_stop(struct nl_seq_iter *iter) |
1da177e4 | 2566 | { |
56d28b1e HX |
2567 | rhashtable_walk_stop(&iter->hti); |
2568 | rhashtable_walk_exit(&iter->hti); | |
1da177e4 LT |
2569 | } |
2570 | ||
56d28b1e | 2571 | static void *__netlink_seq_next(struct seq_file *seq) |
1da177e4 | 2572 | { |
56d28b1e | 2573 | struct nl_seq_iter *iter = seq->private; |
e341694e | 2574 | struct netlink_sock *nlk; |
1da177e4 | 2575 | |
56d28b1e HX |
2576 | do { |
2577 | for (;;) { | |
56d28b1e | 2578 | nlk = rhashtable_walk_next(&iter->hti); |
746fac4d | 2579 | |
56d28b1e HX |
2580 | if (IS_ERR(nlk)) { |
2581 | if (PTR_ERR(nlk) == -EAGAIN) | |
2582 | continue; | |
e341694e | 2583 | |
56d28b1e HX |
2584 | return nlk; |
2585 | } | |
1da177e4 | 2586 | |
56d28b1e HX |
2587 | if (nlk) |
2588 | break; | |
1da177e4 | 2589 | |
56d28b1e HX |
2590 | netlink_walk_stop(iter); |
2591 | if (++iter->link >= MAX_LINKS) | |
2592 | return NULL; | |
da12c90e | 2593 | |
abf9979f | 2594 | netlink_walk_start(iter); |
1da177e4 | 2595 | } |
56d28b1e | 2596 | } while (sock_net(&nlk->sk) != seq_file_net(seq)); |
1da177e4 | 2597 | |
56d28b1e HX |
2598 | return nlk; |
2599 | } | |
1da177e4 | 2600 | |
56d28b1e | 2601 | static void *netlink_seq_start(struct seq_file *seq, loff_t *posp) |
64fbca01 | 2602 | __acquires(RCU) |
56d28b1e HX |
2603 | { |
2604 | struct nl_seq_iter *iter = seq->private; | |
2605 | void *obj = SEQ_START_TOKEN; | |
2606 | loff_t pos; | |
56d28b1e HX |
2607 | |
2608 | iter->link = 0; | |
2609 | ||
abf9979f | 2610 | netlink_walk_start(iter); |
56d28b1e HX |
2611 | |
2612 | for (pos = *posp; pos && obj && !IS_ERR(obj); pos--) | |
2613 | obj = __netlink_seq_next(seq); | |
2614 | ||
2615 | return obj; | |
2616 | } | |
2617 | ||
2618 | static void *netlink_seq_next(struct seq_file *seq, void *v, loff_t *pos) | |
2619 | { | |
2620 | ++*pos; | |
2621 | return __netlink_seq_next(seq); | |
1da177e4 LT |
2622 | } |
2623 | ||
138d0be3 | 2624 | static void netlink_native_seq_stop(struct seq_file *seq, void *v) |
1da177e4 | 2625 | { |
56d28b1e HX |
2626 | struct nl_seq_iter *iter = seq->private; |
2627 | ||
2628 | if (iter->link >= MAX_LINKS) | |
2629 | return; | |
2630 | ||
2631 | netlink_walk_stop(iter); | |
1da177e4 LT |
2632 | } |
2633 | ||
2634 | ||
138d0be3 | 2635 | static int netlink_native_seq_show(struct seq_file *seq, void *v) |
1da177e4 | 2636 | { |
658cb354 | 2637 | if (v == SEQ_START_TOKEN) { |
1da177e4 | 2638 | seq_puts(seq, |
ae552ac2 YB |
2639 | "sk Eth Pid Groups " |
2640 | "Rmem Wmem Dump Locks Drops Inode\n"); | |
658cb354 | 2641 | } else { |
1da177e4 LT |
2642 | struct sock *s = v; |
2643 | struct netlink_sock *nlk = nlk_sk(s); | |
2644 | ||
ea9a0379 | 2645 | seq_printf(seq, "%pK %-3d %-10u %08x %-8d %-8d %-5d %-8d %-8u %-8lu\n", |
1da177e4 LT |
2646 | s, |
2647 | s->sk_protocol, | |
15e47304 | 2648 | nlk->portid, |
513c2500 | 2649 | nlk->groups ? (u32)nlk->groups[0] : 0, |
31e6d363 ED |
2650 | sk_rmem_alloc_get(s), |
2651 | sk_wmem_alloc_get(s), | |
16b304f3 | 2652 | nlk->cb_running, |
41c6d650 | 2653 | refcount_read(&s->sk_refcnt), |
cf0aa4e0 MY |
2654 | atomic_read(&s->sk_drops), |
2655 | sock_i_ino(s) | |
1da177e4 LT |
2656 | ); |
2657 | ||
2658 | } | |
2659 | return 0; | |
2660 | } | |
2661 | ||
138d0be3 YS |
2662 | #ifdef CONFIG_BPF_SYSCALL |
2663 | struct bpf_iter__netlink { | |
2664 | __bpf_md_ptr(struct bpf_iter_meta *, meta); | |
2665 | __bpf_md_ptr(struct netlink_sock *, sk); | |
2666 | }; | |
2667 | ||
2668 | DEFINE_BPF_ITER_FUNC(netlink, struct bpf_iter_meta *meta, struct netlink_sock *sk) | |
2669 | ||
2670 | static int netlink_prog_seq_show(struct bpf_prog *prog, | |
2671 | struct bpf_iter_meta *meta, | |
2672 | void *v) | |
2673 | { | |
2674 | struct bpf_iter__netlink ctx; | |
2675 | ||
2676 | meta->seq_num--; /* skip SEQ_START_TOKEN */ | |
2677 | ctx.meta = meta; | |
2678 | ctx.sk = nlk_sk((struct sock *)v); | |
2679 | return bpf_iter_run_prog(prog, &ctx); | |
2680 | } | |
2681 | ||
2682 | static int netlink_seq_show(struct seq_file *seq, void *v) | |
2683 | { | |
2684 | struct bpf_iter_meta meta; | |
2685 | struct bpf_prog *prog; | |
2686 | ||
2687 | meta.seq = seq; | |
2688 | prog = bpf_iter_get_info(&meta, false); | |
2689 | if (!prog) | |
2690 | return netlink_native_seq_show(seq, v); | |
2691 | ||
2692 | if (v != SEQ_START_TOKEN) | |
2693 | return netlink_prog_seq_show(prog, &meta, v); | |
2694 | ||
2695 | return 0; | |
2696 | } | |
2697 | ||
2698 | static void netlink_seq_stop(struct seq_file *seq, void *v) | |
2699 | { | |
2700 | struct bpf_iter_meta meta; | |
2701 | struct bpf_prog *prog; | |
2702 | ||
2703 | if (!v) { | |
2704 | meta.seq = seq; | |
2705 | prog = bpf_iter_get_info(&meta, true); | |
2706 | if (prog) | |
2707 | (void)netlink_prog_seq_show(prog, &meta, v); | |
2708 | } | |
2709 | ||
2710 | netlink_native_seq_stop(seq, v); | |
2711 | } | |
2712 | #else | |
2713 | static int netlink_seq_show(struct seq_file *seq, void *v) | |
2714 | { | |
2715 | return netlink_native_seq_show(seq, v); | |
2716 | } | |
2717 | ||
2718 | static void netlink_seq_stop(struct seq_file *seq, void *v) | |
2719 | { | |
2720 | netlink_native_seq_stop(seq, v); | |
2721 | } | |
2722 | #endif | |
2723 | ||
56b3d975 | 2724 | static const struct seq_operations netlink_seq_ops = { |
1da177e4 LT |
2725 | .start = netlink_seq_start, |
2726 | .next = netlink_seq_next, | |
2727 | .stop = netlink_seq_stop, | |
2728 | .show = netlink_seq_show, | |
2729 | }; | |
1da177e4 LT |
2730 | #endif |
2731 | ||
2732 | int netlink_register_notifier(struct notifier_block *nb) | |
2733 | { | |
efa172f4 | 2734 | return blocking_notifier_chain_register(&netlink_chain, nb); |
1da177e4 | 2735 | } |
6ac552fd | 2736 | EXPORT_SYMBOL(netlink_register_notifier); |
1da177e4 LT |
2737 | |
2738 | int netlink_unregister_notifier(struct notifier_block *nb) | |
2739 | { | |
efa172f4 | 2740 | return blocking_notifier_chain_unregister(&netlink_chain, nb); |
1da177e4 | 2741 | } |
6ac552fd | 2742 | EXPORT_SYMBOL(netlink_unregister_notifier); |
746fac4d | 2743 | |
90ddc4f0 | 2744 | static const struct proto_ops netlink_ops = { |
1da177e4 LT |
2745 | .family = PF_NETLINK, |
2746 | .owner = THIS_MODULE, | |
2747 | .release = netlink_release, | |
2748 | .bind = netlink_bind, | |
2749 | .connect = netlink_connect, | |
2750 | .socketpair = sock_no_socketpair, | |
2751 | .accept = sock_no_accept, | |
2752 | .getname = netlink_getname, | |
a11e1d43 | 2753 | .poll = datagram_poll, |
025c6818 | 2754 | .ioctl = netlink_ioctl, |
1da177e4 LT |
2755 | .listen = sock_no_listen, |
2756 | .shutdown = sock_no_shutdown, | |
9a4595bc PM |
2757 | .setsockopt = netlink_setsockopt, |
2758 | .getsockopt = netlink_getsockopt, | |
1da177e4 LT |
2759 | .sendmsg = netlink_sendmsg, |
2760 | .recvmsg = netlink_recvmsg, | |
d1b4c689 | 2761 | .mmap = sock_no_mmap, |
1da177e4 LT |
2762 | .sendpage = sock_no_sendpage, |
2763 | }; | |
2764 | ||
ec1b4cf7 | 2765 | static const struct net_proto_family netlink_family_ops = { |
1da177e4 LT |
2766 | .family = PF_NETLINK, |
2767 | .create = netlink_create, | |
2768 | .owner = THIS_MODULE, /* for consistency 8) */ | |
2769 | }; | |
2770 | ||
4665079c | 2771 | static int __net_init netlink_net_init(struct net *net) |
b4b51029 EB |
2772 | { |
2773 | #ifdef CONFIG_PROC_FS | |
c3506372 CH |
2774 | if (!proc_create_net("netlink", 0, net->proc_net, &netlink_seq_ops, |
2775 | sizeof(struct nl_seq_iter))) | |
b4b51029 EB |
2776 | return -ENOMEM; |
2777 | #endif | |
2778 | return 0; | |
2779 | } | |
2780 | ||
4665079c | 2781 | static void __net_exit netlink_net_exit(struct net *net) |
b4b51029 EB |
2782 | { |
2783 | #ifdef CONFIG_PROC_FS | |
ece31ffd | 2784 | remove_proc_entry("netlink", net->proc_net); |
b4b51029 EB |
2785 | #endif |
2786 | } | |
2787 | ||
b963ea89 DM |
2788 | static void __init netlink_add_usersock_entry(void) |
2789 | { | |
5c398dc8 | 2790 | struct listeners *listeners; |
b963ea89 DM |
2791 | int groups = 32; |
2792 | ||
5c398dc8 | 2793 | listeners = kzalloc(sizeof(*listeners) + NLGRPSZ(groups), GFP_KERNEL); |
b963ea89 | 2794 | if (!listeners) |
5c398dc8 | 2795 | panic("netlink_add_usersock_entry: Cannot allocate listeners\n"); |
b963ea89 DM |
2796 | |
2797 | netlink_table_grab(); | |
2798 | ||
2799 | nl_table[NETLINK_USERSOCK].groups = groups; | |
5c398dc8 | 2800 | rcu_assign_pointer(nl_table[NETLINK_USERSOCK].listeners, listeners); |
b963ea89 DM |
2801 | nl_table[NETLINK_USERSOCK].module = THIS_MODULE; |
2802 | nl_table[NETLINK_USERSOCK].registered = 1; | |
9785e10a | 2803 | nl_table[NETLINK_USERSOCK].flags = NL_CFG_F_NONROOT_SEND; |
b963ea89 DM |
2804 | |
2805 | netlink_table_ungrab(); | |
2806 | } | |
2807 | ||
022cbae6 | 2808 | static struct pernet_operations __net_initdata netlink_net_ops = { |
b4b51029 EB |
2809 | .init = netlink_net_init, |
2810 | .exit = netlink_net_exit, | |
2811 | }; | |
2812 | ||
49f7b33e | 2813 | static inline u32 netlink_hash(const void *data, u32 len, u32 seed) |
c428ecd1 HX |
2814 | { |
2815 | const struct netlink_sock *nlk = data; | |
2816 | struct netlink_compare_arg arg; | |
2817 | ||
da314c99 | 2818 | netlink_compare_arg_init(&arg, sock_net(&nlk->sk), nlk->portid); |
11b58ba1 | 2819 | return jhash2((u32 *)&arg, netlink_compare_arg_len / sizeof(u32), seed); |
c428ecd1 HX |
2820 | } |
2821 | ||
2822 | static const struct rhashtable_params netlink_rhashtable_params = { | |
2823 | .head_offset = offsetof(struct netlink_sock, node), | |
2824 | .key_len = netlink_compare_arg_len, | |
c428ecd1 HX |
2825 | .obj_hashfn = netlink_hash, |
2826 | .obj_cmpfn = netlink_compare, | |
b5e2c150 | 2827 | .automatic_shrinking = true, |
c428ecd1 HX |
2828 | }; |
2829 | ||
138d0be3 | 2830 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) |
951cf368 YS |
2831 | BTF_ID_LIST(btf_netlink_sock_id) |
2832 | BTF_ID(struct, netlink_sock) | |
2833 | ||
14fc6bd6 | 2834 | static const struct bpf_iter_seq_info netlink_seq_info = { |
15172a46 YS |
2835 | .seq_ops = &netlink_seq_ops, |
2836 | .init_seq_private = bpf_iter_init_seq_net, | |
2837 | .fini_seq_private = bpf_iter_fini_seq_net, | |
2838 | .seq_priv_size = sizeof(struct nl_seq_iter), | |
14fc6bd6 YS |
2839 | }; |
2840 | ||
2841 | static struct bpf_iter_reg netlink_reg_info = { | |
2842 | .target = "netlink", | |
3c32cc1b YS |
2843 | .ctx_arg_info_size = 1, |
2844 | .ctx_arg_info = { | |
2845 | { offsetof(struct bpf_iter__netlink, sk), | |
2846 | PTR_TO_BTF_ID_OR_NULL }, | |
2847 | }, | |
14fc6bd6 | 2848 | .seq_info = &netlink_seq_info, |
15172a46 YS |
2849 | }; |
2850 | ||
138d0be3 YS |
2851 | static int __init bpf_iter_register(void) |
2852 | { | |
951cf368 | 2853 | netlink_reg_info.ctx_arg_info[0].btf_id = *btf_netlink_sock_id; |
15172a46 | 2854 | return bpf_iter_reg_target(&netlink_reg_info); |
138d0be3 YS |
2855 | } |
2856 | #endif | |
2857 | ||
1da177e4 LT |
2858 | static int __init netlink_proto_init(void) |
2859 | { | |
1da177e4 | 2860 | int i; |
1da177e4 LT |
2861 | int err = proto_register(&netlink_proto, 0); |
2862 | ||
2863 | if (err != 0) | |
2864 | goto out; | |
2865 | ||
138d0be3 YS |
2866 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS) |
2867 | err = bpf_iter_register(); | |
2868 | if (err) | |
2869 | goto out; | |
2870 | #endif | |
2871 | ||
c593642c | 2872 | BUILD_BUG_ON(sizeof(struct netlink_skb_parms) > sizeof_field(struct sk_buff, cb)); |
1da177e4 | 2873 | |
0da974f4 | 2874 | nl_table = kcalloc(MAX_LINKS, sizeof(*nl_table), GFP_KERNEL); |
fab2caf6 AM |
2875 | if (!nl_table) |
2876 | goto panic; | |
1da177e4 | 2877 | |
1da177e4 | 2878 | for (i = 0; i < MAX_LINKS; i++) { |
c428ecd1 HX |
2879 | if (rhashtable_init(&nl_table[i].hash, |
2880 | &netlink_rhashtable_params) < 0) { | |
e341694e TG |
2881 | while (--i > 0) |
2882 | rhashtable_destroy(&nl_table[i].hash); | |
1da177e4 | 2883 | kfree(nl_table); |
fab2caf6 | 2884 | goto panic; |
1da177e4 | 2885 | } |
1da177e4 LT |
2886 | } |
2887 | ||
b963ea89 DM |
2888 | netlink_add_usersock_entry(); |
2889 | ||
1da177e4 | 2890 | sock_register(&netlink_family_ops); |
b4b51029 | 2891 | register_pernet_subsys(&netlink_net_ops); |
25e3f70f | 2892 | register_pernet_subsys(&netlink_tap_net_ops); |
746fac4d | 2893 | /* The netlink device handler may be needed early. */ |
1da177e4 LT |
2894 | rtnetlink_init(); |
2895 | out: | |
2896 | return err; | |
fab2caf6 AM |
2897 | panic: |
2898 | panic("netlink_init: Cannot allocate nl_table\n"); | |
1da177e4 LT |
2899 | } |
2900 | ||
1da177e4 | 2901 | core_initcall(netlink_proto_init); |