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1 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
2 | ||
3 | #include <linux/workqueue.h> | |
4 | #include <linux/rtnetlink.h> | |
5 | #include <linux/cache.h> | |
6 | #include <linux/slab.h> | |
7 | #include <linux/list.h> | |
8 | #include <linux/delay.h> | |
9 | #include <linux/sched.h> | |
10 | #include <linux/idr.h> | |
11 | #include <linux/rculist.h> | |
12 | #include <linux/nsproxy.h> | |
13 | #include <linux/fs.h> | |
14 | #include <linux/proc_ns.h> | |
15 | #include <linux/file.h> | |
16 | #include <linux/export.h> | |
17 | #include <linux/user_namespace.h> | |
18 | #include <net/net_namespace.h> | |
19 | #include <net/netns/generic.h> | |
20 | ||
21 | /* | |
22 | * Our network namespace constructor/destructor lists | |
23 | */ | |
24 | ||
25 | static LIST_HEAD(pernet_list); | |
26 | static struct list_head *first_device = &pernet_list; | |
27 | DEFINE_MUTEX(net_mutex); | |
28 | ||
29 | LIST_HEAD(net_namespace_list); | |
30 | EXPORT_SYMBOL_GPL(net_namespace_list); | |
31 | ||
32 | struct net init_net = { | |
33 | .dev_base_head = LIST_HEAD_INIT(init_net.dev_base_head), | |
34 | }; | |
35 | EXPORT_SYMBOL(init_net); | |
36 | ||
37 | #define INITIAL_NET_GEN_PTRS 13 /* +1 for len +2 for rcu_head */ | |
38 | ||
39 | static unsigned int max_gen_ptrs = INITIAL_NET_GEN_PTRS; | |
40 | ||
41 | static struct net_generic *net_alloc_generic(void) | |
42 | { | |
43 | struct net_generic *ng; | |
44 | size_t generic_size = offsetof(struct net_generic, ptr[max_gen_ptrs]); | |
45 | ||
46 | ng = kzalloc(generic_size, GFP_KERNEL); | |
47 | if (ng) | |
48 | ng->len = max_gen_ptrs; | |
49 | ||
50 | return ng; | |
51 | } | |
52 | ||
53 | static int net_assign_generic(struct net *net, int id, void *data) | |
54 | { | |
55 | struct net_generic *ng, *old_ng; | |
56 | ||
57 | BUG_ON(!mutex_is_locked(&net_mutex)); | |
58 | BUG_ON(id == 0); | |
59 | ||
60 | old_ng = rcu_dereference_protected(net->gen, | |
61 | lockdep_is_held(&net_mutex)); | |
62 | ng = old_ng; | |
63 | if (old_ng->len >= id) | |
64 | goto assign; | |
65 | ||
66 | ng = net_alloc_generic(); | |
67 | if (ng == NULL) | |
68 | return -ENOMEM; | |
69 | ||
70 | /* | |
71 | * Some synchronisation notes: | |
72 | * | |
73 | * The net_generic explores the net->gen array inside rcu | |
74 | * read section. Besides once set the net->gen->ptr[x] | |
75 | * pointer never changes (see rules in netns/generic.h). | |
76 | * | |
77 | * That said, we simply duplicate this array and schedule | |
78 | * the old copy for kfree after a grace period. | |
79 | */ | |
80 | ||
81 | memcpy(&ng->ptr, &old_ng->ptr, old_ng->len * sizeof(void*)); | |
82 | ||
83 | rcu_assign_pointer(net->gen, ng); | |
84 | kfree_rcu(old_ng, rcu); | |
85 | assign: | |
86 | ng->ptr[id - 1] = data; | |
87 | return 0; | |
88 | } | |
89 | ||
90 | static int ops_init(const struct pernet_operations *ops, struct net *net) | |
91 | { | |
92 | int err = -ENOMEM; | |
93 | void *data = NULL; | |
94 | ||
95 | if (ops->id && ops->size) { | |
96 | data = kzalloc(ops->size, GFP_KERNEL); | |
97 | if (!data) | |
98 | goto out; | |
99 | ||
100 | err = net_assign_generic(net, *ops->id, data); | |
101 | if (err) | |
102 | goto cleanup; | |
103 | } | |
104 | err = 0; | |
105 | if (ops->init) | |
106 | err = ops->init(net); | |
107 | if (!err) | |
108 | return 0; | |
109 | ||
110 | cleanup: | |
111 | kfree(data); | |
112 | ||
113 | out: | |
114 | return err; | |
115 | } | |
116 | ||
117 | static void ops_free(const struct pernet_operations *ops, struct net *net) | |
118 | { | |
119 | if (ops->id && ops->size) { | |
120 | int id = *ops->id; | |
121 | kfree(net_generic(net, id)); | |
122 | } | |
123 | } | |
124 | ||
125 | static void ops_exit_list(const struct pernet_operations *ops, | |
126 | struct list_head *net_exit_list) | |
127 | { | |
128 | struct net *net; | |
129 | if (ops->exit) { | |
130 | list_for_each_entry(net, net_exit_list, exit_list) | |
131 | ops->exit(net); | |
132 | } | |
133 | if (ops->exit_batch) | |
134 | ops->exit_batch(net_exit_list); | |
135 | } | |
136 | ||
137 | static void ops_free_list(const struct pernet_operations *ops, | |
138 | struct list_head *net_exit_list) | |
139 | { | |
140 | struct net *net; | |
141 | if (ops->size && ops->id) { | |
142 | list_for_each_entry(net, net_exit_list, exit_list) | |
143 | ops_free(ops, net); | |
144 | } | |
145 | } | |
146 | ||
147 | /* | |
148 | * setup_net runs the initializers for the network namespace object. | |
149 | */ | |
150 | static __net_init int setup_net(struct net *net, struct user_namespace *user_ns) | |
151 | { | |
152 | /* Must be called with net_mutex held */ | |
153 | const struct pernet_operations *ops, *saved_ops; | |
154 | int error = 0; | |
155 | LIST_HEAD(net_exit_list); | |
156 | ||
157 | atomic_set(&net->count, 1); | |
158 | atomic_set(&net->passive, 1); | |
159 | net->dev_base_seq = 1; | |
160 | net->user_ns = user_ns; | |
161 | ||
162 | #ifdef NETNS_REFCNT_DEBUG | |
163 | atomic_set(&net->use_count, 0); | |
164 | #endif | |
165 | ||
166 | list_for_each_entry(ops, &pernet_list, list) { | |
167 | error = ops_init(ops, net); | |
168 | if (error < 0) | |
169 | goto out_undo; | |
170 | } | |
171 | out: | |
172 | return error; | |
173 | ||
174 | out_undo: | |
175 | /* Walk through the list backwards calling the exit functions | |
176 | * for the pernet modules whose init functions did not fail. | |
177 | */ | |
178 | list_add(&net->exit_list, &net_exit_list); | |
179 | saved_ops = ops; | |
180 | list_for_each_entry_continue_reverse(ops, &pernet_list, list) | |
181 | ops_exit_list(ops, &net_exit_list); | |
182 | ||
183 | ops = saved_ops; | |
184 | list_for_each_entry_continue_reverse(ops, &pernet_list, list) | |
185 | ops_free_list(ops, &net_exit_list); | |
186 | ||
187 | rcu_barrier(); | |
188 | goto out; | |
189 | } | |
190 | ||
191 | ||
192 | #ifdef CONFIG_NET_NS | |
193 | static struct kmem_cache *net_cachep; | |
194 | static struct workqueue_struct *netns_wq; | |
195 | ||
196 | static struct net *net_alloc(void) | |
197 | { | |
198 | struct net *net = NULL; | |
199 | struct net_generic *ng; | |
200 | ||
201 | ng = net_alloc_generic(); | |
202 | if (!ng) | |
203 | goto out; | |
204 | ||
205 | net = kmem_cache_zalloc(net_cachep, GFP_KERNEL); | |
206 | if (!net) | |
207 | goto out_free; | |
208 | ||
209 | rcu_assign_pointer(net->gen, ng); | |
210 | out: | |
211 | return net; | |
212 | ||
213 | out_free: | |
214 | kfree(ng); | |
215 | goto out; | |
216 | } | |
217 | ||
218 | static void net_free(struct net *net) | |
219 | { | |
220 | #ifdef NETNS_REFCNT_DEBUG | |
221 | if (unlikely(atomic_read(&net->use_count) != 0)) { | |
222 | pr_emerg("network namespace not free! Usage: %d\n", | |
223 | atomic_read(&net->use_count)); | |
224 | return; | |
225 | } | |
226 | #endif | |
227 | kfree(rcu_access_pointer(net->gen)); | |
228 | kmem_cache_free(net_cachep, net); | |
229 | } | |
230 | ||
231 | void net_drop_ns(void *p) | |
232 | { | |
233 | struct net *ns = p; | |
234 | if (ns && atomic_dec_and_test(&ns->passive)) | |
235 | net_free(ns); | |
236 | } | |
237 | ||
238 | struct net *copy_net_ns(unsigned long flags, | |
239 | struct user_namespace *user_ns, struct net *old_net) | |
240 | { | |
241 | struct net *net; | |
242 | int rv; | |
243 | ||
244 | if (!(flags & CLONE_NEWNET)) | |
245 | return get_net(old_net); | |
246 | ||
247 | net = net_alloc(); | |
248 | if (!net) | |
249 | return ERR_PTR(-ENOMEM); | |
250 | ||
251 | get_user_ns(user_ns); | |
252 | ||
253 | mutex_lock(&net_mutex); | |
254 | rv = setup_net(net, user_ns); | |
255 | if (rv == 0) { | |
256 | rtnl_lock(); | |
257 | list_add_tail_rcu(&net->list, &net_namespace_list); | |
258 | rtnl_unlock(); | |
259 | } | |
260 | mutex_unlock(&net_mutex); | |
261 | if (rv < 0) { | |
262 | put_user_ns(user_ns); | |
263 | net_drop_ns(net); | |
264 | return ERR_PTR(rv); | |
265 | } | |
266 | return net; | |
267 | } | |
268 | ||
269 | static DEFINE_SPINLOCK(cleanup_list_lock); | |
270 | static LIST_HEAD(cleanup_list); /* Must hold cleanup_list_lock to touch */ | |
271 | ||
272 | static void cleanup_net(struct work_struct *work) | |
273 | { | |
274 | const struct pernet_operations *ops; | |
275 | struct net *net, *tmp; | |
276 | struct list_head net_kill_list; | |
277 | LIST_HEAD(net_exit_list); | |
278 | ||
279 | /* Atomically snapshot the list of namespaces to cleanup */ | |
280 | spin_lock_irq(&cleanup_list_lock); | |
281 | list_replace_init(&cleanup_list, &net_kill_list); | |
282 | spin_unlock_irq(&cleanup_list_lock); | |
283 | ||
284 | mutex_lock(&net_mutex); | |
285 | ||
286 | /* Don't let anyone else find us. */ | |
287 | rtnl_lock(); | |
288 | list_for_each_entry(net, &net_kill_list, cleanup_list) { | |
289 | list_del_rcu(&net->list); | |
290 | list_add_tail(&net->exit_list, &net_exit_list); | |
291 | } | |
292 | rtnl_unlock(); | |
293 | ||
294 | /* | |
295 | * Another CPU might be rcu-iterating the list, wait for it. | |
296 | * This needs to be before calling the exit() notifiers, so | |
297 | * the rcu_barrier() below isn't sufficient alone. | |
298 | */ | |
299 | synchronize_rcu(); | |
300 | ||
301 | /* Run all of the network namespace exit methods */ | |
302 | list_for_each_entry_reverse(ops, &pernet_list, list) | |
303 | ops_exit_list(ops, &net_exit_list); | |
304 | ||
305 | /* Free the net generic variables */ | |
306 | list_for_each_entry_reverse(ops, &pernet_list, list) | |
307 | ops_free_list(ops, &net_exit_list); | |
308 | ||
309 | mutex_unlock(&net_mutex); | |
310 | ||
311 | /* Ensure there are no outstanding rcu callbacks using this | |
312 | * network namespace. | |
313 | */ | |
314 | rcu_barrier(); | |
315 | ||
316 | /* Finally it is safe to free my network namespace structure */ | |
317 | list_for_each_entry_safe(net, tmp, &net_exit_list, exit_list) { | |
318 | list_del_init(&net->exit_list); | |
319 | put_user_ns(net->user_ns); | |
320 | net_drop_ns(net); | |
321 | } | |
322 | } | |
323 | static DECLARE_WORK(net_cleanup_work, cleanup_net); | |
324 | ||
325 | void __put_net(struct net *net) | |
326 | { | |
327 | /* Cleanup the network namespace in process context */ | |
328 | unsigned long flags; | |
329 | ||
330 | spin_lock_irqsave(&cleanup_list_lock, flags); | |
331 | list_add(&net->cleanup_list, &cleanup_list); | |
332 | spin_unlock_irqrestore(&cleanup_list_lock, flags); | |
333 | ||
334 | queue_work(netns_wq, &net_cleanup_work); | |
335 | } | |
336 | EXPORT_SYMBOL_GPL(__put_net); | |
337 | ||
338 | struct net *get_net_ns_by_fd(int fd) | |
339 | { | |
340 | struct proc_ns *ei; | |
341 | struct file *file; | |
342 | struct net *net; | |
343 | ||
344 | file = proc_ns_fget(fd); | |
345 | if (IS_ERR(file)) | |
346 | return ERR_CAST(file); | |
347 | ||
348 | ei = get_proc_ns(file_inode(file)); | |
349 | if (ei->ns_ops == &netns_operations) | |
350 | net = get_net(ei->ns); | |
351 | else | |
352 | net = ERR_PTR(-EINVAL); | |
353 | ||
354 | fput(file); | |
355 | return net; | |
356 | } | |
357 | ||
358 | #else | |
359 | struct net *get_net_ns_by_fd(int fd) | |
360 | { | |
361 | return ERR_PTR(-EINVAL); | |
362 | } | |
363 | #endif | |
364 | ||
365 | struct net *get_net_ns_by_pid(pid_t pid) | |
366 | { | |
367 | struct task_struct *tsk; | |
368 | struct net *net; | |
369 | ||
370 | /* Lookup the network namespace */ | |
371 | net = ERR_PTR(-ESRCH); | |
372 | rcu_read_lock(); | |
373 | tsk = find_task_by_vpid(pid); | |
374 | if (tsk) { | |
375 | struct nsproxy *nsproxy; | |
376 | task_lock(tsk); | |
377 | nsproxy = tsk->nsproxy; | |
378 | if (nsproxy) | |
379 | net = get_net(nsproxy->net_ns); | |
380 | task_unlock(tsk); | |
381 | } | |
382 | rcu_read_unlock(); | |
383 | return net; | |
384 | } | |
385 | EXPORT_SYMBOL_GPL(get_net_ns_by_pid); | |
386 | ||
387 | static __net_init int net_ns_net_init(struct net *net) | |
388 | { | |
389 | return proc_alloc_inum(&net->ns.inum); | |
390 | } | |
391 | ||
392 | static __net_exit void net_ns_net_exit(struct net *net) | |
393 | { | |
394 | proc_free_inum(net->ns.inum); | |
395 | } | |
396 | ||
397 | static struct pernet_operations __net_initdata net_ns_ops = { | |
398 | .init = net_ns_net_init, | |
399 | .exit = net_ns_net_exit, | |
400 | }; | |
401 | ||
402 | static int __init net_ns_init(void) | |
403 | { | |
404 | struct net_generic *ng; | |
405 | ||
406 | #ifdef CONFIG_NET_NS | |
407 | net_cachep = kmem_cache_create("net_namespace", sizeof(struct net), | |
408 | SMP_CACHE_BYTES, | |
409 | SLAB_PANIC, NULL); | |
410 | ||
411 | /* Create workqueue for cleanup */ | |
412 | netns_wq = create_singlethread_workqueue("netns"); | |
413 | if (!netns_wq) | |
414 | panic("Could not create netns workq"); | |
415 | #endif | |
416 | ||
417 | ng = net_alloc_generic(); | |
418 | if (!ng) | |
419 | panic("Could not allocate generic netns"); | |
420 | ||
421 | rcu_assign_pointer(init_net.gen, ng); | |
422 | ||
423 | mutex_lock(&net_mutex); | |
424 | if (setup_net(&init_net, &init_user_ns)) | |
425 | panic("Could not setup the initial network namespace"); | |
426 | ||
427 | rtnl_lock(); | |
428 | list_add_tail_rcu(&init_net.list, &net_namespace_list); | |
429 | rtnl_unlock(); | |
430 | ||
431 | mutex_unlock(&net_mutex); | |
432 | ||
433 | register_pernet_subsys(&net_ns_ops); | |
434 | ||
435 | return 0; | |
436 | } | |
437 | ||
438 | pure_initcall(net_ns_init); | |
439 | ||
440 | #ifdef CONFIG_NET_NS | |
441 | static int __register_pernet_operations(struct list_head *list, | |
442 | struct pernet_operations *ops) | |
443 | { | |
444 | struct net *net; | |
445 | int error; | |
446 | LIST_HEAD(net_exit_list); | |
447 | ||
448 | list_add_tail(&ops->list, list); | |
449 | if (ops->init || (ops->id && ops->size)) { | |
450 | for_each_net(net) { | |
451 | error = ops_init(ops, net); | |
452 | if (error) | |
453 | goto out_undo; | |
454 | list_add_tail(&net->exit_list, &net_exit_list); | |
455 | } | |
456 | } | |
457 | return 0; | |
458 | ||
459 | out_undo: | |
460 | /* If I have an error cleanup all namespaces I initialized */ | |
461 | list_del(&ops->list); | |
462 | ops_exit_list(ops, &net_exit_list); | |
463 | ops_free_list(ops, &net_exit_list); | |
464 | return error; | |
465 | } | |
466 | ||
467 | static void __unregister_pernet_operations(struct pernet_operations *ops) | |
468 | { | |
469 | struct net *net; | |
470 | LIST_HEAD(net_exit_list); | |
471 | ||
472 | list_del(&ops->list); | |
473 | for_each_net(net) | |
474 | list_add_tail(&net->exit_list, &net_exit_list); | |
475 | ops_exit_list(ops, &net_exit_list); | |
476 | ops_free_list(ops, &net_exit_list); | |
477 | } | |
478 | ||
479 | #else | |
480 | ||
481 | static int __register_pernet_operations(struct list_head *list, | |
482 | struct pernet_operations *ops) | |
483 | { | |
484 | return ops_init(ops, &init_net); | |
485 | } | |
486 | ||
487 | static void __unregister_pernet_operations(struct pernet_operations *ops) | |
488 | { | |
489 | LIST_HEAD(net_exit_list); | |
490 | list_add(&init_net.exit_list, &net_exit_list); | |
491 | ops_exit_list(ops, &net_exit_list); | |
492 | ops_free_list(ops, &net_exit_list); | |
493 | } | |
494 | ||
495 | #endif /* CONFIG_NET_NS */ | |
496 | ||
497 | static DEFINE_IDA(net_generic_ids); | |
498 | ||
499 | static int register_pernet_operations(struct list_head *list, | |
500 | struct pernet_operations *ops) | |
501 | { | |
502 | int error; | |
503 | ||
504 | if (ops->id) { | |
505 | again: | |
506 | error = ida_get_new_above(&net_generic_ids, 1, ops->id); | |
507 | if (error < 0) { | |
508 | if (error == -EAGAIN) { | |
509 | ida_pre_get(&net_generic_ids, GFP_KERNEL); | |
510 | goto again; | |
511 | } | |
512 | return error; | |
513 | } | |
514 | max_gen_ptrs = max_t(unsigned int, max_gen_ptrs, *ops->id); | |
515 | } | |
516 | error = __register_pernet_operations(list, ops); | |
517 | if (error) { | |
518 | rcu_barrier(); | |
519 | if (ops->id) | |
520 | ida_remove(&net_generic_ids, *ops->id); | |
521 | } | |
522 | ||
523 | return error; | |
524 | } | |
525 | ||
526 | static void unregister_pernet_operations(struct pernet_operations *ops) | |
527 | { | |
528 | ||
529 | __unregister_pernet_operations(ops); | |
530 | rcu_barrier(); | |
531 | if (ops->id) | |
532 | ida_remove(&net_generic_ids, *ops->id); | |
533 | } | |
534 | ||
535 | /** | |
536 | * register_pernet_subsys - register a network namespace subsystem | |
537 | * @ops: pernet operations structure for the subsystem | |
538 | * | |
539 | * Register a subsystem which has init and exit functions | |
540 | * that are called when network namespaces are created and | |
541 | * destroyed respectively. | |
542 | * | |
543 | * When registered all network namespace init functions are | |
544 | * called for every existing network namespace. Allowing kernel | |
545 | * modules to have a race free view of the set of network namespaces. | |
546 | * | |
547 | * When a new network namespace is created all of the init | |
548 | * methods are called in the order in which they were registered. | |
549 | * | |
550 | * When a network namespace is destroyed all of the exit methods | |
551 | * are called in the reverse of the order with which they were | |
552 | * registered. | |
553 | */ | |
554 | int register_pernet_subsys(struct pernet_operations *ops) | |
555 | { | |
556 | int error; | |
557 | mutex_lock(&net_mutex); | |
558 | error = register_pernet_operations(first_device, ops); | |
559 | mutex_unlock(&net_mutex); | |
560 | return error; | |
561 | } | |
562 | EXPORT_SYMBOL_GPL(register_pernet_subsys); | |
563 | ||
564 | /** | |
565 | * unregister_pernet_subsys - unregister a network namespace subsystem | |
566 | * @ops: pernet operations structure to manipulate | |
567 | * | |
568 | * Remove the pernet operations structure from the list to be | |
569 | * used when network namespaces are created or destroyed. In | |
570 | * addition run the exit method for all existing network | |
571 | * namespaces. | |
572 | */ | |
573 | void unregister_pernet_subsys(struct pernet_operations *ops) | |
574 | { | |
575 | mutex_lock(&net_mutex); | |
576 | unregister_pernet_operations(ops); | |
577 | mutex_unlock(&net_mutex); | |
578 | } | |
579 | EXPORT_SYMBOL_GPL(unregister_pernet_subsys); | |
580 | ||
581 | /** | |
582 | * register_pernet_device - register a network namespace device | |
583 | * @ops: pernet operations structure for the subsystem | |
584 | * | |
585 | * Register a device which has init and exit functions | |
586 | * that are called when network namespaces are created and | |
587 | * destroyed respectively. | |
588 | * | |
589 | * When registered all network namespace init functions are | |
590 | * called for every existing network namespace. Allowing kernel | |
591 | * modules to have a race free view of the set of network namespaces. | |
592 | * | |
593 | * When a new network namespace is created all of the init | |
594 | * methods are called in the order in which they were registered. | |
595 | * | |
596 | * When a network namespace is destroyed all of the exit methods | |
597 | * are called in the reverse of the order with which they were | |
598 | * registered. | |
599 | */ | |
600 | int register_pernet_device(struct pernet_operations *ops) | |
601 | { | |
602 | int error; | |
603 | mutex_lock(&net_mutex); | |
604 | error = register_pernet_operations(&pernet_list, ops); | |
605 | if (!error && (first_device == &pernet_list)) | |
606 | first_device = &ops->list; | |
607 | mutex_unlock(&net_mutex); | |
608 | return error; | |
609 | } | |
610 | EXPORT_SYMBOL_GPL(register_pernet_device); | |
611 | ||
612 | /** | |
613 | * unregister_pernet_device - unregister a network namespace netdevice | |
614 | * @ops: pernet operations structure to manipulate | |
615 | * | |
616 | * Remove the pernet operations structure from the list to be | |
617 | * used when network namespaces are created or destroyed. In | |
618 | * addition run the exit method for all existing network | |
619 | * namespaces. | |
620 | */ | |
621 | void unregister_pernet_device(struct pernet_operations *ops) | |
622 | { | |
623 | mutex_lock(&net_mutex); | |
624 | if (&ops->list == first_device) | |
625 | first_device = first_device->next; | |
626 | unregister_pernet_operations(ops); | |
627 | mutex_unlock(&net_mutex); | |
628 | } | |
629 | EXPORT_SYMBOL_GPL(unregister_pernet_device); | |
630 | ||
631 | #ifdef CONFIG_NET_NS | |
632 | static void *netns_get(struct task_struct *task) | |
633 | { | |
634 | struct net *net = NULL; | |
635 | struct nsproxy *nsproxy; | |
636 | ||
637 | task_lock(task); | |
638 | nsproxy = task->nsproxy; | |
639 | if (nsproxy) | |
640 | net = get_net(nsproxy->net_ns); | |
641 | task_unlock(task); | |
642 | ||
643 | return net; | |
644 | } | |
645 | ||
646 | static void netns_put(void *ns) | |
647 | { | |
648 | put_net(ns); | |
649 | } | |
650 | ||
651 | static int netns_install(struct nsproxy *nsproxy, void *ns) | |
652 | { | |
653 | struct net *net = ns; | |
654 | ||
655 | if (!ns_capable(net->user_ns, CAP_SYS_ADMIN) || | |
656 | !ns_capable(current_user_ns(), CAP_SYS_ADMIN)) | |
657 | return -EPERM; | |
658 | ||
659 | put_net(nsproxy->net_ns); | |
660 | nsproxy->net_ns = get_net(net); | |
661 | return 0; | |
662 | } | |
663 | ||
664 | static unsigned int netns_inum(void *ns) | |
665 | { | |
666 | struct net *net = ns; | |
667 | return net->ns.inum; | |
668 | } | |
669 | ||
670 | const struct proc_ns_operations netns_operations = { | |
671 | .name = "net", | |
672 | .type = CLONE_NEWNET, | |
673 | .get = netns_get, | |
674 | .put = netns_put, | |
675 | .install = netns_install, | |
676 | .inum = netns_inum, | |
677 | }; | |
678 | #endif |