1 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
14 #include <linux/proc_ns.h>
15 #include <linux/file.h>
16 #include <linux/export.h>
17 #include <linux/user_namespace.h>
18 #include <linux/net_namespace.h>
20 #include <net/netlink.h>
21 #include <net/net_namespace.h>
22 #include <net/netns/generic.h>
25 * Our network namespace constructor/destructor lists
28 static LIST_HEAD(pernet_list
);
29 static struct list_head
*first_device
= &pernet_list
;
30 DEFINE_MUTEX(net_mutex
);
32 LIST_HEAD(net_namespace_list
);
33 EXPORT_SYMBOL_GPL(net_namespace_list
);
35 struct net init_net
= {
36 .dev_base_head
= LIST_HEAD_INIT(init_net
.dev_base_head
),
38 EXPORT_SYMBOL(init_net
);
40 static bool init_net_initialized
;
42 #define INITIAL_NET_GEN_PTRS 13 /* +1 for len +2 for rcu_head */
44 static unsigned int max_gen_ptrs
= INITIAL_NET_GEN_PTRS
;
46 static struct net_generic
*net_alloc_generic(void)
48 struct net_generic
*ng
;
49 size_t generic_size
= offsetof(struct net_generic
, ptr
[max_gen_ptrs
]);
51 ng
= kzalloc(generic_size
, GFP_KERNEL
);
53 ng
->len
= max_gen_ptrs
;
58 static int net_assign_generic(struct net
*net
, unsigned int id
, void *data
)
60 struct net_generic
*ng
, *old_ng
;
62 BUG_ON(!mutex_is_locked(&net_mutex
));
65 old_ng
= rcu_dereference_protected(net
->gen
,
66 lockdep_is_held(&net_mutex
));
68 if (old_ng
->len
>= id
)
71 ng
= net_alloc_generic();
76 * Some synchronisation notes:
78 * The net_generic explores the net->gen array inside rcu
79 * read section. Besides once set the net->gen->ptr[x]
80 * pointer never changes (see rules in netns/generic.h).
82 * That said, we simply duplicate this array and schedule
83 * the old copy for kfree after a grace period.
86 memcpy(&ng
->ptr
, &old_ng
->ptr
, old_ng
->len
* sizeof(void*));
88 rcu_assign_pointer(net
->gen
, ng
);
89 kfree_rcu(old_ng
, rcu
);
91 ng
->ptr
[id
- 1] = data
;
95 static int ops_init(const struct pernet_operations
*ops
, struct net
*net
)
100 if (ops
->id
&& ops
->size
) {
101 data
= kzalloc(ops
->size
, GFP_KERNEL
);
105 err
= net_assign_generic(net
, *ops
->id
, data
);
111 err
= ops
->init(net
);
122 static void ops_free(const struct pernet_operations
*ops
, struct net
*net
)
124 if (ops
->id
&& ops
->size
) {
125 kfree(net_generic(net
, *ops
->id
));
129 static void ops_exit_list(const struct pernet_operations
*ops
,
130 struct list_head
*net_exit_list
)
134 list_for_each_entry(net
, net_exit_list
, exit_list
)
138 ops
->exit_batch(net_exit_list
);
141 static void ops_free_list(const struct pernet_operations
*ops
,
142 struct list_head
*net_exit_list
)
145 if (ops
->size
&& ops
->id
) {
146 list_for_each_entry(net
, net_exit_list
, exit_list
)
151 /* should be called with nsid_lock held */
152 static int alloc_netid(struct net
*net
, struct net
*peer
, int reqid
)
154 int min
= 0, max
= 0;
161 return idr_alloc(&net
->netns_ids
, peer
, min
, max
, GFP_ATOMIC
);
164 /* This function is used by idr_for_each(). If net is equal to peer, the
165 * function returns the id so that idr_for_each() stops. Because we cannot
166 * returns the id 0 (idr_for_each() will not stop), we return the magic value
167 * NET_ID_ZERO (-1) for it.
169 #define NET_ID_ZERO -1
170 static int net_eq_idr(int id
, void *net
, void *peer
)
172 if (net_eq(net
, peer
))
173 return id
? : NET_ID_ZERO
;
177 /* Should be called with nsid_lock held. If a new id is assigned, the bool alloc
178 * is set to true, thus the caller knows that the new id must be notified via
181 static int __peernet2id_alloc(struct net
*net
, struct net
*peer
, bool *alloc
)
183 int id
= idr_for_each(&net
->netns_ids
, net_eq_idr
, peer
);
184 bool alloc_it
= *alloc
;
188 /* Magic value for id 0. */
189 if (id
== NET_ID_ZERO
)
195 id
= alloc_netid(net
, peer
, -1);
197 return id
>= 0 ? id
: NETNSA_NSID_NOT_ASSIGNED
;
200 return NETNSA_NSID_NOT_ASSIGNED
;
203 /* should be called with nsid_lock held */
204 static int __peernet2id(struct net
*net
, struct net
*peer
)
208 return __peernet2id_alloc(net
, peer
, &no
);
211 static void rtnl_net_notifyid(struct net
*net
, int cmd
, int id
);
212 /* This function returns the id of a peer netns. If no id is assigned, one will
213 * be allocated and returned.
215 int peernet2id_alloc(struct net
*net
, struct net
*peer
)
221 if (atomic_read(&net
->count
) == 0)
222 return NETNSA_NSID_NOT_ASSIGNED
;
223 spin_lock_irqsave(&net
->nsid_lock
, flags
);
224 alloc
= atomic_read(&peer
->count
) == 0 ? false : true;
225 id
= __peernet2id_alloc(net
, peer
, &alloc
);
226 spin_unlock_irqrestore(&net
->nsid_lock
, flags
);
227 if (alloc
&& id
>= 0)
228 rtnl_net_notifyid(net
, RTM_NEWNSID
, id
);
232 /* This function returns, if assigned, the id of a peer netns. */
233 int peernet2id(struct net
*net
, struct net
*peer
)
238 spin_lock_irqsave(&net
->nsid_lock
, flags
);
239 id
= __peernet2id(net
, peer
);
240 spin_unlock_irqrestore(&net
->nsid_lock
, flags
);
243 EXPORT_SYMBOL(peernet2id
);
245 /* This function returns true is the peer netns has an id assigned into the
248 bool peernet_has_id(struct net
*net
, struct net
*peer
)
250 return peernet2id(net
, peer
) >= 0;
253 struct net
*get_net_ns_by_id(struct net
*net
, int id
)
262 spin_lock_irqsave(&net
->nsid_lock
, flags
);
263 peer
= idr_find(&net
->netns_ids
, id
);
266 spin_unlock_irqrestore(&net
->nsid_lock
, flags
);
273 * setup_net runs the initializers for the network namespace object.
275 static __net_init
int setup_net(struct net
*net
, struct user_namespace
*user_ns
)
277 /* Must be called with net_mutex held */
278 const struct pernet_operations
*ops
, *saved_ops
;
280 LIST_HEAD(net_exit_list
);
282 atomic_set(&net
->count
, 1);
283 atomic_set(&net
->passive
, 1);
284 net
->dev_base_seq
= 1;
285 net
->user_ns
= user_ns
;
286 idr_init(&net
->netns_ids
);
287 spin_lock_init(&net
->nsid_lock
);
289 list_for_each_entry(ops
, &pernet_list
, list
) {
290 error
= ops_init(ops
, net
);
298 /* Walk through the list backwards calling the exit functions
299 * for the pernet modules whose init functions did not fail.
301 list_add(&net
->exit_list
, &net_exit_list
);
303 list_for_each_entry_continue_reverse(ops
, &pernet_list
, list
)
304 ops_exit_list(ops
, &net_exit_list
);
307 list_for_each_entry_continue_reverse(ops
, &pernet_list
, list
)
308 ops_free_list(ops
, &net_exit_list
);
316 static struct ucounts
*inc_net_namespaces(struct user_namespace
*ns
)
318 return inc_ucount(ns
, current_euid(), UCOUNT_NET_NAMESPACES
);
321 static void dec_net_namespaces(struct ucounts
*ucounts
)
323 dec_ucount(ucounts
, UCOUNT_NET_NAMESPACES
);
326 static struct kmem_cache
*net_cachep
;
327 static struct workqueue_struct
*netns_wq
;
329 static struct net
*net_alloc(void)
331 struct net
*net
= NULL
;
332 struct net_generic
*ng
;
334 ng
= net_alloc_generic();
338 net
= kmem_cache_zalloc(net_cachep
, GFP_KERNEL
);
342 rcu_assign_pointer(net
->gen
, ng
);
351 static void net_free(struct net
*net
)
353 kfree(rcu_access_pointer(net
->gen
));
354 kmem_cache_free(net_cachep
, net
);
357 void net_drop_ns(void *p
)
360 if (ns
&& atomic_dec_and_test(&ns
->passive
))
364 struct net
*copy_net_ns(unsigned long flags
,
365 struct user_namespace
*user_ns
, struct net
*old_net
)
367 struct ucounts
*ucounts
;
371 if (!(flags
& CLONE_NEWNET
))
372 return get_net(old_net
);
374 ucounts
= inc_net_namespaces(user_ns
);
376 return ERR_PTR(-ENOSPC
);
380 dec_net_namespaces(ucounts
);
381 return ERR_PTR(-ENOMEM
);
384 get_user_ns(user_ns
);
386 rv
= mutex_lock_killable(&net_mutex
);
389 dec_net_namespaces(ucounts
);
390 put_user_ns(user_ns
);
394 net
->ucounts
= ucounts
;
395 rv
= setup_net(net
, user_ns
);
398 list_add_tail_rcu(&net
->list
, &net_namespace_list
);
401 mutex_unlock(&net_mutex
);
403 dec_net_namespaces(ucounts
);
404 put_user_ns(user_ns
);
411 static DEFINE_SPINLOCK(cleanup_list_lock
);
412 static LIST_HEAD(cleanup_list
); /* Must hold cleanup_list_lock to touch */
414 static void cleanup_net(struct work_struct
*work
)
416 const struct pernet_operations
*ops
;
417 struct net
*net
, *tmp
;
418 struct list_head net_kill_list
;
419 LIST_HEAD(net_exit_list
);
421 /* Atomically snapshot the list of namespaces to cleanup */
422 spin_lock_irq(&cleanup_list_lock
);
423 list_replace_init(&cleanup_list
, &net_kill_list
);
424 spin_unlock_irq(&cleanup_list_lock
);
426 mutex_lock(&net_mutex
);
428 /* Don't let anyone else find us. */
430 list_for_each_entry(net
, &net_kill_list
, cleanup_list
) {
431 list_del_rcu(&net
->list
);
432 list_add_tail(&net
->exit_list
, &net_exit_list
);
436 spin_lock_irq(&tmp
->nsid_lock
);
437 id
= __peernet2id(tmp
, net
);
439 idr_remove(&tmp
->netns_ids
, id
);
440 spin_unlock_irq(&tmp
->nsid_lock
);
442 rtnl_net_notifyid(tmp
, RTM_DELNSID
, id
);
444 spin_lock_irq(&net
->nsid_lock
);
445 idr_destroy(&net
->netns_ids
);
446 spin_unlock_irq(&net
->nsid_lock
);
452 * Another CPU might be rcu-iterating the list, wait for it.
453 * This needs to be before calling the exit() notifiers, so
454 * the rcu_barrier() below isn't sufficient alone.
458 /* Run all of the network namespace exit methods */
459 list_for_each_entry_reverse(ops
, &pernet_list
, list
)
460 ops_exit_list(ops
, &net_exit_list
);
462 /* Free the net generic variables */
463 list_for_each_entry_reverse(ops
, &pernet_list
, list
)
464 ops_free_list(ops
, &net_exit_list
);
466 mutex_unlock(&net_mutex
);
468 /* Ensure there are no outstanding rcu callbacks using this
473 /* Finally it is safe to free my network namespace structure */
474 list_for_each_entry_safe(net
, tmp
, &net_exit_list
, exit_list
) {
475 list_del_init(&net
->exit_list
);
476 dec_net_namespaces(net
->ucounts
);
477 put_user_ns(net
->user_ns
);
481 static DECLARE_WORK(net_cleanup_work
, cleanup_net
);
483 void __put_net(struct net
*net
)
485 /* Cleanup the network namespace in process context */
488 spin_lock_irqsave(&cleanup_list_lock
, flags
);
489 list_add(&net
->cleanup_list
, &cleanup_list
);
490 spin_unlock_irqrestore(&cleanup_list_lock
, flags
);
492 queue_work(netns_wq
, &net_cleanup_work
);
494 EXPORT_SYMBOL_GPL(__put_net
);
496 struct net
*get_net_ns_by_fd(int fd
)
499 struct ns_common
*ns
;
502 file
= proc_ns_fget(fd
);
504 return ERR_CAST(file
);
506 ns
= get_proc_ns(file_inode(file
));
507 if (ns
->ops
== &netns_operations
)
508 net
= get_net(container_of(ns
, struct net
, ns
));
510 net
= ERR_PTR(-EINVAL
);
517 struct net
*get_net_ns_by_fd(int fd
)
519 return ERR_PTR(-EINVAL
);
522 EXPORT_SYMBOL_GPL(get_net_ns_by_fd
);
524 struct net
*get_net_ns_by_pid(pid_t pid
)
526 struct task_struct
*tsk
;
529 /* Lookup the network namespace */
530 net
= ERR_PTR(-ESRCH
);
532 tsk
= find_task_by_vpid(pid
);
534 struct nsproxy
*nsproxy
;
536 nsproxy
= tsk
->nsproxy
;
538 net
= get_net(nsproxy
->net_ns
);
544 EXPORT_SYMBOL_GPL(get_net_ns_by_pid
);
546 static __net_init
int net_ns_net_init(struct net
*net
)
549 net
->ns
.ops
= &netns_operations
;
551 return ns_alloc_inum(&net
->ns
);
554 static __net_exit
void net_ns_net_exit(struct net
*net
)
556 ns_free_inum(&net
->ns
);
559 static struct pernet_operations __net_initdata net_ns_ops
= {
560 .init
= net_ns_net_init
,
561 .exit
= net_ns_net_exit
,
564 static const struct nla_policy rtnl_net_policy
[NETNSA_MAX
+ 1] = {
565 [NETNSA_NONE
] = { .type
= NLA_UNSPEC
},
566 [NETNSA_NSID
] = { .type
= NLA_S32
},
567 [NETNSA_PID
] = { .type
= NLA_U32
},
568 [NETNSA_FD
] = { .type
= NLA_U32
},
571 static int rtnl_net_newid(struct sk_buff
*skb
, struct nlmsghdr
*nlh
)
573 struct net
*net
= sock_net(skb
->sk
);
574 struct nlattr
*tb
[NETNSA_MAX
+ 1];
579 err
= nlmsg_parse(nlh
, sizeof(struct rtgenmsg
), tb
, NETNSA_MAX
,
583 if (!tb
[NETNSA_NSID
])
585 nsid
= nla_get_s32(tb
[NETNSA_NSID
]);
588 peer
= get_net_ns_by_pid(nla_get_u32(tb
[NETNSA_PID
]));
589 else if (tb
[NETNSA_FD
])
590 peer
= get_net_ns_by_fd(nla_get_u32(tb
[NETNSA_FD
]));
594 return PTR_ERR(peer
);
596 spin_lock_irqsave(&net
->nsid_lock
, flags
);
597 if (__peernet2id(net
, peer
) >= 0) {
598 spin_unlock_irqrestore(&net
->nsid_lock
, flags
);
603 err
= alloc_netid(net
, peer
, nsid
);
604 spin_unlock_irqrestore(&net
->nsid_lock
, flags
);
606 rtnl_net_notifyid(net
, RTM_NEWNSID
, err
);
614 static int rtnl_net_get_size(void)
616 return NLMSG_ALIGN(sizeof(struct rtgenmsg
))
617 + nla_total_size(sizeof(s32
)) /* NETNSA_NSID */
621 static int rtnl_net_fill(struct sk_buff
*skb
, u32 portid
, u32 seq
, int flags
,
622 int cmd
, struct net
*net
, int nsid
)
624 struct nlmsghdr
*nlh
;
625 struct rtgenmsg
*rth
;
627 nlh
= nlmsg_put(skb
, portid
, seq
, cmd
, sizeof(*rth
), flags
);
631 rth
= nlmsg_data(nlh
);
632 rth
->rtgen_family
= AF_UNSPEC
;
634 if (nla_put_s32(skb
, NETNSA_NSID
, nsid
))
635 goto nla_put_failure
;
641 nlmsg_cancel(skb
, nlh
);
645 static int rtnl_net_getid(struct sk_buff
*skb
, struct nlmsghdr
*nlh
)
647 struct net
*net
= sock_net(skb
->sk
);
648 struct nlattr
*tb
[NETNSA_MAX
+ 1];
653 err
= nlmsg_parse(nlh
, sizeof(struct rtgenmsg
), tb
, NETNSA_MAX
,
658 peer
= get_net_ns_by_pid(nla_get_u32(tb
[NETNSA_PID
]));
659 else if (tb
[NETNSA_FD
])
660 peer
= get_net_ns_by_fd(nla_get_u32(tb
[NETNSA_FD
]));
665 return PTR_ERR(peer
);
667 msg
= nlmsg_new(rtnl_net_get_size(), GFP_KERNEL
);
673 id
= peernet2id(net
, peer
);
674 err
= rtnl_net_fill(msg
, NETLINK_CB(skb
).portid
, nlh
->nlmsg_seq
, 0,
675 RTM_NEWNSID
, net
, id
);
679 err
= rtnl_unicast(msg
, net
, NETLINK_CB(skb
).portid
);
689 struct rtnl_net_dump_cb
{
692 struct netlink_callback
*cb
;
697 static int rtnl_net_dumpid_one(int id
, void *peer
, void *data
)
699 struct rtnl_net_dump_cb
*net_cb
= (struct rtnl_net_dump_cb
*)data
;
702 if (net_cb
->idx
< net_cb
->s_idx
)
705 ret
= rtnl_net_fill(net_cb
->skb
, NETLINK_CB(net_cb
->cb
->skb
).portid
,
706 net_cb
->cb
->nlh
->nlmsg_seq
, NLM_F_MULTI
,
707 RTM_NEWNSID
, net_cb
->net
, id
);
716 static int rtnl_net_dumpid(struct sk_buff
*skb
, struct netlink_callback
*cb
)
718 struct net
*net
= sock_net(skb
->sk
);
719 struct rtnl_net_dump_cb net_cb
= {
724 .s_idx
= cb
->args
[0],
728 spin_lock_irqsave(&net
->nsid_lock
, flags
);
729 idr_for_each(&net
->netns_ids
, rtnl_net_dumpid_one
, &net_cb
);
730 spin_unlock_irqrestore(&net
->nsid_lock
, flags
);
732 cb
->args
[0] = net_cb
.idx
;
736 static void rtnl_net_notifyid(struct net
*net
, int cmd
, int id
)
741 msg
= nlmsg_new(rtnl_net_get_size(), GFP_KERNEL
);
745 err
= rtnl_net_fill(msg
, 0, 0, 0, cmd
, net
, id
);
749 rtnl_notify(msg
, net
, 0, RTNLGRP_NSID
, NULL
, 0);
755 rtnl_set_sk_err(net
, RTNLGRP_NSID
, err
);
758 static int __init
net_ns_init(void)
760 struct net_generic
*ng
;
763 net_cachep
= kmem_cache_create("net_namespace", sizeof(struct net
),
767 /* Create workqueue for cleanup */
768 netns_wq
= create_singlethread_workqueue("netns");
770 panic("Could not create netns workq");
773 ng
= net_alloc_generic();
775 panic("Could not allocate generic netns");
777 rcu_assign_pointer(init_net
.gen
, ng
);
779 mutex_lock(&net_mutex
);
780 if (setup_net(&init_net
, &init_user_ns
))
781 panic("Could not setup the initial network namespace");
783 init_net_initialized
= true;
786 list_add_tail_rcu(&init_net
.list
, &net_namespace_list
);
789 mutex_unlock(&net_mutex
);
791 register_pernet_subsys(&net_ns_ops
);
793 rtnl_register(PF_UNSPEC
, RTM_NEWNSID
, rtnl_net_newid
, NULL
, NULL
);
794 rtnl_register(PF_UNSPEC
, RTM_GETNSID
, rtnl_net_getid
, rtnl_net_dumpid
,
800 pure_initcall(net_ns_init
);
803 static int __register_pernet_operations(struct list_head
*list
,
804 struct pernet_operations
*ops
)
808 LIST_HEAD(net_exit_list
);
810 list_add_tail(&ops
->list
, list
);
811 if (ops
->init
|| (ops
->id
&& ops
->size
)) {
813 error
= ops_init(ops
, net
);
816 list_add_tail(&net
->exit_list
, &net_exit_list
);
822 /* If I have an error cleanup all namespaces I initialized */
823 list_del(&ops
->list
);
824 ops_exit_list(ops
, &net_exit_list
);
825 ops_free_list(ops
, &net_exit_list
);
829 static void __unregister_pernet_operations(struct pernet_operations
*ops
)
832 LIST_HEAD(net_exit_list
);
834 list_del(&ops
->list
);
836 list_add_tail(&net
->exit_list
, &net_exit_list
);
837 ops_exit_list(ops
, &net_exit_list
);
838 ops_free_list(ops
, &net_exit_list
);
843 static int __register_pernet_operations(struct list_head
*list
,
844 struct pernet_operations
*ops
)
846 if (!init_net_initialized
) {
847 list_add_tail(&ops
->list
, list
);
851 return ops_init(ops
, &init_net
);
854 static void __unregister_pernet_operations(struct pernet_operations
*ops
)
856 if (!init_net_initialized
) {
857 list_del(&ops
->list
);
859 LIST_HEAD(net_exit_list
);
860 list_add(&init_net
.exit_list
, &net_exit_list
);
861 ops_exit_list(ops
, &net_exit_list
);
862 ops_free_list(ops
, &net_exit_list
);
866 #endif /* CONFIG_NET_NS */
868 static DEFINE_IDA(net_generic_ids
);
870 static int register_pernet_operations(struct list_head
*list
,
871 struct pernet_operations
*ops
)
877 error
= ida_get_new_above(&net_generic_ids
, 1, ops
->id
);
879 if (error
== -EAGAIN
) {
880 ida_pre_get(&net_generic_ids
, GFP_KERNEL
);
885 max_gen_ptrs
= max(max_gen_ptrs
, *ops
->id
);
887 error
= __register_pernet_operations(list
, ops
);
891 ida_remove(&net_generic_ids
, *ops
->id
);
897 static void unregister_pernet_operations(struct pernet_operations
*ops
)
900 __unregister_pernet_operations(ops
);
903 ida_remove(&net_generic_ids
, *ops
->id
);
907 * register_pernet_subsys - register a network namespace subsystem
908 * @ops: pernet operations structure for the subsystem
910 * Register a subsystem which has init and exit functions
911 * that are called when network namespaces are created and
912 * destroyed respectively.
914 * When registered all network namespace init functions are
915 * called for every existing network namespace. Allowing kernel
916 * modules to have a race free view of the set of network namespaces.
918 * When a new network namespace is created all of the init
919 * methods are called in the order in which they were registered.
921 * When a network namespace is destroyed all of the exit methods
922 * are called in the reverse of the order with which they were
925 int register_pernet_subsys(struct pernet_operations
*ops
)
928 mutex_lock(&net_mutex
);
929 error
= register_pernet_operations(first_device
, ops
);
930 mutex_unlock(&net_mutex
);
933 EXPORT_SYMBOL_GPL(register_pernet_subsys
);
936 * unregister_pernet_subsys - unregister a network namespace subsystem
937 * @ops: pernet operations structure to manipulate
939 * Remove the pernet operations structure from the list to be
940 * used when network namespaces are created or destroyed. In
941 * addition run the exit method for all existing network
944 void unregister_pernet_subsys(struct pernet_operations
*ops
)
946 mutex_lock(&net_mutex
);
947 unregister_pernet_operations(ops
);
948 mutex_unlock(&net_mutex
);
950 EXPORT_SYMBOL_GPL(unregister_pernet_subsys
);
953 * register_pernet_device - register a network namespace device
954 * @ops: pernet operations structure for the subsystem
956 * Register a device which has init and exit functions
957 * that are called when network namespaces are created and
958 * destroyed respectively.
960 * When registered all network namespace init functions are
961 * called for every existing network namespace. Allowing kernel
962 * modules to have a race free view of the set of network namespaces.
964 * When a new network namespace is created all of the init
965 * methods are called in the order in which they were registered.
967 * When a network namespace is destroyed all of the exit methods
968 * are called in the reverse of the order with which they were
971 int register_pernet_device(struct pernet_operations
*ops
)
974 mutex_lock(&net_mutex
);
975 error
= register_pernet_operations(&pernet_list
, ops
);
976 if (!error
&& (first_device
== &pernet_list
))
977 first_device
= &ops
->list
;
978 mutex_unlock(&net_mutex
);
981 EXPORT_SYMBOL_GPL(register_pernet_device
);
984 * unregister_pernet_device - unregister a network namespace netdevice
985 * @ops: pernet operations structure to manipulate
987 * Remove the pernet operations structure from the list to be
988 * used when network namespaces are created or destroyed. In
989 * addition run the exit method for all existing network
992 void unregister_pernet_device(struct pernet_operations
*ops
)
994 mutex_lock(&net_mutex
);
995 if (&ops
->list
== first_device
)
996 first_device
= first_device
->next
;
997 unregister_pernet_operations(ops
);
998 mutex_unlock(&net_mutex
);
1000 EXPORT_SYMBOL_GPL(unregister_pernet_device
);
1002 #ifdef CONFIG_NET_NS
1003 static struct ns_common
*netns_get(struct task_struct
*task
)
1005 struct net
*net
= NULL
;
1006 struct nsproxy
*nsproxy
;
1009 nsproxy
= task
->nsproxy
;
1011 net
= get_net(nsproxy
->net_ns
);
1014 return net
? &net
->ns
: NULL
;
1017 static inline struct net
*to_net_ns(struct ns_common
*ns
)
1019 return container_of(ns
, struct net
, ns
);
1022 static void netns_put(struct ns_common
*ns
)
1024 put_net(to_net_ns(ns
));
1027 static int netns_install(struct nsproxy
*nsproxy
, struct ns_common
*ns
)
1029 struct net
*net
= to_net_ns(ns
);
1031 if (!ns_capable(net
->user_ns
, CAP_SYS_ADMIN
) ||
1032 !ns_capable(current_user_ns(), CAP_SYS_ADMIN
))
1035 put_net(nsproxy
->net_ns
);
1036 nsproxy
->net_ns
= get_net(net
);
1040 static struct user_namespace
*netns_owner(struct ns_common
*ns
)
1042 return to_net_ns(ns
)->user_ns
;
1045 const struct proc_ns_operations netns_operations
= {
1047 .type
= CLONE_NEWNET
,
1050 .install
= netns_install
,
1051 .owner
= netns_owner
,