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
, 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
) {
126 kfree(net_generic(net
, id
));
130 static void ops_exit_list(const struct pernet_operations
*ops
,
131 struct list_head
*net_exit_list
)
135 list_for_each_entry(net
, net_exit_list
, exit_list
)
139 ops
->exit_batch(net_exit_list
);
142 static void ops_free_list(const struct pernet_operations
*ops
,
143 struct list_head
*net_exit_list
)
146 if (ops
->size
&& ops
->id
) {
147 list_for_each_entry(net
, net_exit_list
, exit_list
)
152 /* should be called with nsid_lock held */
153 static int alloc_netid(struct net
*net
, struct net
*peer
, int reqid
)
155 int min
= 0, max
= 0;
162 return idr_alloc(&net
->netns_ids
, peer
, min
, max
, GFP_ATOMIC
);
165 /* This function is used by idr_for_each(). If net is equal to peer, the
166 * function returns the id so that idr_for_each() stops. Because we cannot
167 * returns the id 0 (idr_for_each() will not stop), we return the magic value
168 * NET_ID_ZERO (-1) for it.
170 #define NET_ID_ZERO -1
171 static int net_eq_idr(int id
, void *net
, void *peer
)
173 if (net_eq(net
, peer
))
174 return id
? : NET_ID_ZERO
;
178 /* Should be called with nsid_lock held. If a new id is assigned, the bool alloc
179 * is set to true, thus the caller knows that the new id must be notified via
182 static int __peernet2id_alloc(struct net
*net
, struct net
*peer
, bool *alloc
)
184 int id
= idr_for_each(&net
->netns_ids
, net_eq_idr
, peer
);
185 bool alloc_it
= *alloc
;
189 /* Magic value for id 0. */
190 if (id
== NET_ID_ZERO
)
196 id
= alloc_netid(net
, peer
, -1);
198 return id
>= 0 ? id
: NETNSA_NSID_NOT_ASSIGNED
;
201 return NETNSA_NSID_NOT_ASSIGNED
;
204 /* should be called with nsid_lock held */
205 static int __peernet2id(struct net
*net
, struct net
*peer
)
209 return __peernet2id_alloc(net
, peer
, &no
);
212 static void rtnl_net_notifyid(struct net
*net
, int cmd
, int id
);
213 /* This function returns the id of a peer netns. If no id is assigned, one will
214 * be allocated and returned.
216 int peernet2id_alloc(struct net
*net
, struct net
*peer
)
221 spin_lock_bh(&net
->nsid_lock
);
222 alloc
= atomic_read(&peer
->count
) == 0 ? false : true;
223 id
= __peernet2id_alloc(net
, peer
, &alloc
);
224 spin_unlock_bh(&net
->nsid_lock
);
225 if (alloc
&& id
>= 0)
226 rtnl_net_notifyid(net
, RTM_NEWNSID
, id
);
230 /* This function returns, if assigned, the id of a peer netns. */
231 int peernet2id(struct net
*net
, struct net
*peer
)
235 spin_lock_bh(&net
->nsid_lock
);
236 id
= __peernet2id(net
, peer
);
237 spin_unlock_bh(&net
->nsid_lock
);
240 EXPORT_SYMBOL(peernet2id
);
242 /* This function returns true is the peer netns has an id assigned into the
245 bool peernet_has_id(struct net
*net
, struct net
*peer
)
247 return peernet2id(net
, peer
) >= 0;
250 struct net
*get_net_ns_by_id(struct net
*net
, int id
)
258 spin_lock_bh(&net
->nsid_lock
);
259 peer
= idr_find(&net
->netns_ids
, id
);
262 spin_unlock_bh(&net
->nsid_lock
);
269 * setup_net runs the initializers for the network namespace object.
271 static __net_init
int setup_net(struct net
*net
, struct user_namespace
*user_ns
)
273 /* Must be called with net_mutex held */
274 const struct pernet_operations
*ops
, *saved_ops
;
276 LIST_HEAD(net_exit_list
);
278 atomic_set(&net
->count
, 1);
279 atomic_set(&net
->passive
, 1);
280 net
->dev_base_seq
= 1;
281 net
->user_ns
= user_ns
;
282 idr_init(&net
->netns_ids
);
283 spin_lock_init(&net
->nsid_lock
);
285 list_for_each_entry(ops
, &pernet_list
, list
) {
286 error
= ops_init(ops
, net
);
294 /* Walk through the list backwards calling the exit functions
295 * for the pernet modules whose init functions did not fail.
297 list_add(&net
->exit_list
, &net_exit_list
);
299 list_for_each_entry_continue_reverse(ops
, &pernet_list
, list
)
300 ops_exit_list(ops
, &net_exit_list
);
303 list_for_each_entry_continue_reverse(ops
, &pernet_list
, list
)
304 ops_free_list(ops
, &net_exit_list
);
312 static struct kmem_cache
*net_cachep
;
313 static struct workqueue_struct
*netns_wq
;
315 static struct net
*net_alloc(void)
317 struct net
*net
= NULL
;
318 struct net_generic
*ng
;
320 ng
= net_alloc_generic();
324 net
= kmem_cache_zalloc(net_cachep
, GFP_KERNEL
);
328 rcu_assign_pointer(net
->gen
, ng
);
337 static void net_free(struct net
*net
)
339 kfree(rcu_access_pointer(net
->gen
));
340 kmem_cache_free(net_cachep
, net
);
343 void net_drop_ns(void *p
)
346 if (ns
&& atomic_dec_and_test(&ns
->passive
))
350 struct net
*copy_net_ns(unsigned long flags
,
351 struct user_namespace
*user_ns
, struct net
*old_net
)
356 if (!(flags
& CLONE_NEWNET
))
357 return get_net(old_net
);
361 return ERR_PTR(-ENOMEM
);
363 get_user_ns(user_ns
);
365 mutex_lock(&net_mutex
);
366 rv
= setup_net(net
, user_ns
);
369 list_add_tail_rcu(&net
->list
, &net_namespace_list
);
372 mutex_unlock(&net_mutex
);
374 put_user_ns(user_ns
);
381 static DEFINE_SPINLOCK(cleanup_list_lock
);
382 static LIST_HEAD(cleanup_list
); /* Must hold cleanup_list_lock to touch */
384 static void cleanup_net(struct work_struct
*work
)
386 const struct pernet_operations
*ops
;
387 struct net
*net
, *tmp
;
388 struct list_head net_kill_list
;
389 LIST_HEAD(net_exit_list
);
391 /* Atomically snapshot the list of namespaces to cleanup */
392 spin_lock_irq(&cleanup_list_lock
);
393 list_replace_init(&cleanup_list
, &net_kill_list
);
394 spin_unlock_irq(&cleanup_list_lock
);
396 mutex_lock(&net_mutex
);
398 /* Don't let anyone else find us. */
400 list_for_each_entry(net
, &net_kill_list
, cleanup_list
) {
401 list_del_rcu(&net
->list
);
402 list_add_tail(&net
->exit_list
, &net_exit_list
);
406 spin_lock_bh(&tmp
->nsid_lock
);
407 id
= __peernet2id(tmp
, net
);
409 idr_remove(&tmp
->netns_ids
, id
);
410 spin_unlock_bh(&tmp
->nsid_lock
);
412 rtnl_net_notifyid(tmp
, RTM_DELNSID
, id
);
414 spin_lock_bh(&net
->nsid_lock
);
415 idr_destroy(&net
->netns_ids
);
416 spin_unlock_bh(&net
->nsid_lock
);
422 * Another CPU might be rcu-iterating the list, wait for it.
423 * This needs to be before calling the exit() notifiers, so
424 * the rcu_barrier() below isn't sufficient alone.
428 /* Run all of the network namespace exit methods */
429 list_for_each_entry_reverse(ops
, &pernet_list
, list
)
430 ops_exit_list(ops
, &net_exit_list
);
432 /* Free the net generic variables */
433 list_for_each_entry_reverse(ops
, &pernet_list
, list
)
434 ops_free_list(ops
, &net_exit_list
);
436 mutex_unlock(&net_mutex
);
438 /* Ensure there are no outstanding rcu callbacks using this
443 /* Finally it is safe to free my network namespace structure */
444 list_for_each_entry_safe(net
, tmp
, &net_exit_list
, exit_list
) {
445 list_del_init(&net
->exit_list
);
446 put_user_ns(net
->user_ns
);
450 static DECLARE_WORK(net_cleanup_work
, cleanup_net
);
452 void __put_net(struct net
*net
)
454 /* Cleanup the network namespace in process context */
457 spin_lock_irqsave(&cleanup_list_lock
, flags
);
458 list_add(&net
->cleanup_list
, &cleanup_list
);
459 spin_unlock_irqrestore(&cleanup_list_lock
, flags
);
461 queue_work(netns_wq
, &net_cleanup_work
);
463 EXPORT_SYMBOL_GPL(__put_net
);
465 struct net
*get_net_ns_by_fd(int fd
)
468 struct ns_common
*ns
;
471 file
= proc_ns_fget(fd
);
473 return ERR_CAST(file
);
475 ns
= get_proc_ns(file_inode(file
));
476 if (ns
->ops
== &netns_operations
)
477 net
= get_net(container_of(ns
, struct net
, ns
));
479 net
= ERR_PTR(-EINVAL
);
486 struct net
*get_net_ns_by_fd(int fd
)
488 return ERR_PTR(-EINVAL
);
491 EXPORT_SYMBOL_GPL(get_net_ns_by_fd
);
493 struct net
*get_net_ns_by_pid(pid_t pid
)
495 struct task_struct
*tsk
;
498 /* Lookup the network namespace */
499 net
= ERR_PTR(-ESRCH
);
501 tsk
= find_task_by_vpid(pid
);
503 struct nsproxy
*nsproxy
;
505 nsproxy
= tsk
->nsproxy
;
507 net
= get_net(nsproxy
->net_ns
);
513 EXPORT_SYMBOL_GPL(get_net_ns_by_pid
);
515 static __net_init
int net_ns_net_init(struct net
*net
)
518 net
->ns
.ops
= &netns_operations
;
520 return ns_alloc_inum(&net
->ns
);
523 static __net_exit
void net_ns_net_exit(struct net
*net
)
525 ns_free_inum(&net
->ns
);
528 static struct pernet_operations __net_initdata net_ns_ops
= {
529 .init
= net_ns_net_init
,
530 .exit
= net_ns_net_exit
,
533 static const struct nla_policy rtnl_net_policy
[NETNSA_MAX
+ 1] = {
534 [NETNSA_NONE
] = { .type
= NLA_UNSPEC
},
535 [NETNSA_NSID
] = { .type
= NLA_S32
},
536 [NETNSA_PID
] = { .type
= NLA_U32
},
537 [NETNSA_FD
] = { .type
= NLA_U32
},
540 static int rtnl_net_newid(struct sk_buff
*skb
, struct nlmsghdr
*nlh
)
542 struct net
*net
= sock_net(skb
->sk
);
543 struct nlattr
*tb
[NETNSA_MAX
+ 1];
547 err
= nlmsg_parse(nlh
, sizeof(struct rtgenmsg
), tb
, NETNSA_MAX
,
551 if (!tb
[NETNSA_NSID
])
553 nsid
= nla_get_s32(tb
[NETNSA_NSID
]);
556 peer
= get_net_ns_by_pid(nla_get_u32(tb
[NETNSA_PID
]));
557 else if (tb
[NETNSA_FD
])
558 peer
= get_net_ns_by_fd(nla_get_u32(tb
[NETNSA_FD
]));
562 return PTR_ERR(peer
);
564 spin_lock_bh(&net
->nsid_lock
);
565 if (__peernet2id(net
, peer
) >= 0) {
566 spin_unlock_bh(&net
->nsid_lock
);
571 err
= alloc_netid(net
, peer
, nsid
);
572 spin_unlock_bh(&net
->nsid_lock
);
574 rtnl_net_notifyid(net
, RTM_NEWNSID
, err
);
582 static int rtnl_net_get_size(void)
584 return NLMSG_ALIGN(sizeof(struct rtgenmsg
))
585 + nla_total_size(sizeof(s32
)) /* NETNSA_NSID */
589 static int rtnl_net_fill(struct sk_buff
*skb
, u32 portid
, u32 seq
, int flags
,
590 int cmd
, struct net
*net
, int nsid
)
592 struct nlmsghdr
*nlh
;
593 struct rtgenmsg
*rth
;
595 nlh
= nlmsg_put(skb
, portid
, seq
, cmd
, sizeof(*rth
), flags
);
599 rth
= nlmsg_data(nlh
);
600 rth
->rtgen_family
= AF_UNSPEC
;
602 if (nla_put_s32(skb
, NETNSA_NSID
, nsid
))
603 goto nla_put_failure
;
609 nlmsg_cancel(skb
, nlh
);
613 static int rtnl_net_getid(struct sk_buff
*skb
, struct nlmsghdr
*nlh
)
615 struct net
*net
= sock_net(skb
->sk
);
616 struct nlattr
*tb
[NETNSA_MAX
+ 1];
621 err
= nlmsg_parse(nlh
, sizeof(struct rtgenmsg
), tb
, NETNSA_MAX
,
626 peer
= get_net_ns_by_pid(nla_get_u32(tb
[NETNSA_PID
]));
627 else if (tb
[NETNSA_FD
])
628 peer
= get_net_ns_by_fd(nla_get_u32(tb
[NETNSA_FD
]));
633 return PTR_ERR(peer
);
635 msg
= nlmsg_new(rtnl_net_get_size(), GFP_KERNEL
);
641 id
= peernet2id(net
, peer
);
642 err
= rtnl_net_fill(msg
, NETLINK_CB(skb
).portid
, nlh
->nlmsg_seq
, 0,
643 RTM_NEWNSID
, net
, id
);
647 err
= rtnl_unicast(msg
, net
, NETLINK_CB(skb
).portid
);
657 struct rtnl_net_dump_cb
{
660 struct netlink_callback
*cb
;
665 static int rtnl_net_dumpid_one(int id
, void *peer
, void *data
)
667 struct rtnl_net_dump_cb
*net_cb
= (struct rtnl_net_dump_cb
*)data
;
670 if (net_cb
->idx
< net_cb
->s_idx
)
673 ret
= rtnl_net_fill(net_cb
->skb
, NETLINK_CB(net_cb
->cb
->skb
).portid
,
674 net_cb
->cb
->nlh
->nlmsg_seq
, NLM_F_MULTI
,
675 RTM_NEWNSID
, net_cb
->net
, id
);
684 static int rtnl_net_dumpid(struct sk_buff
*skb
, struct netlink_callback
*cb
)
686 struct net
*net
= sock_net(skb
->sk
);
687 struct rtnl_net_dump_cb net_cb
= {
692 .s_idx
= cb
->args
[0],
695 spin_lock_bh(&net
->nsid_lock
);
696 idr_for_each(&net
->netns_ids
, rtnl_net_dumpid_one
, &net_cb
);
697 spin_unlock_bh(&net
->nsid_lock
);
699 cb
->args
[0] = net_cb
.idx
;
703 static void rtnl_net_notifyid(struct net
*net
, int cmd
, int id
)
708 msg
= nlmsg_new(rtnl_net_get_size(), GFP_KERNEL
);
712 err
= rtnl_net_fill(msg
, 0, 0, 0, cmd
, net
, id
);
716 rtnl_notify(msg
, net
, 0, RTNLGRP_NSID
, NULL
, 0);
722 rtnl_set_sk_err(net
, RTNLGRP_NSID
, err
);
725 static int __init
net_ns_init(void)
727 struct net_generic
*ng
;
730 net_cachep
= kmem_cache_create("net_namespace", sizeof(struct net
),
734 /* Create workqueue for cleanup */
735 netns_wq
= create_singlethread_workqueue("netns");
737 panic("Could not create netns workq");
740 ng
= net_alloc_generic();
742 panic("Could not allocate generic netns");
744 rcu_assign_pointer(init_net
.gen
, ng
);
746 mutex_lock(&net_mutex
);
747 if (setup_net(&init_net
, &init_user_ns
))
748 panic("Could not setup the initial network namespace");
750 init_net_initialized
= true;
753 list_add_tail_rcu(&init_net
.list
, &net_namespace_list
);
756 mutex_unlock(&net_mutex
);
758 register_pernet_subsys(&net_ns_ops
);
760 rtnl_register(PF_UNSPEC
, RTM_NEWNSID
, rtnl_net_newid
, NULL
, NULL
);
761 rtnl_register(PF_UNSPEC
, RTM_GETNSID
, rtnl_net_getid
, rtnl_net_dumpid
,
767 pure_initcall(net_ns_init
);
770 static int __register_pernet_operations(struct list_head
*list
,
771 struct pernet_operations
*ops
)
775 LIST_HEAD(net_exit_list
);
777 list_add_tail(&ops
->list
, list
);
778 if (ops
->init
|| (ops
->id
&& ops
->size
)) {
780 error
= ops_init(ops
, net
);
783 list_add_tail(&net
->exit_list
, &net_exit_list
);
789 /* If I have an error cleanup all namespaces I initialized */
790 list_del(&ops
->list
);
791 ops_exit_list(ops
, &net_exit_list
);
792 ops_free_list(ops
, &net_exit_list
);
796 static void __unregister_pernet_operations(struct pernet_operations
*ops
)
799 LIST_HEAD(net_exit_list
);
801 list_del(&ops
->list
);
803 list_add_tail(&net
->exit_list
, &net_exit_list
);
804 ops_exit_list(ops
, &net_exit_list
);
805 ops_free_list(ops
, &net_exit_list
);
810 static int __register_pernet_operations(struct list_head
*list
,
811 struct pernet_operations
*ops
)
813 if (!init_net_initialized
) {
814 list_add_tail(&ops
->list
, list
);
818 return ops_init(ops
, &init_net
);
821 static void __unregister_pernet_operations(struct pernet_operations
*ops
)
823 if (!init_net_initialized
) {
824 list_del(&ops
->list
);
826 LIST_HEAD(net_exit_list
);
827 list_add(&init_net
.exit_list
, &net_exit_list
);
828 ops_exit_list(ops
, &net_exit_list
);
829 ops_free_list(ops
, &net_exit_list
);
833 #endif /* CONFIG_NET_NS */
835 static DEFINE_IDA(net_generic_ids
);
837 static int register_pernet_operations(struct list_head
*list
,
838 struct pernet_operations
*ops
)
844 error
= ida_get_new_above(&net_generic_ids
, 1, ops
->id
);
846 if (error
== -EAGAIN
) {
847 ida_pre_get(&net_generic_ids
, GFP_KERNEL
);
852 max_gen_ptrs
= max_t(unsigned int, max_gen_ptrs
, *ops
->id
);
854 error
= __register_pernet_operations(list
, ops
);
858 ida_remove(&net_generic_ids
, *ops
->id
);
864 static void unregister_pernet_operations(struct pernet_operations
*ops
)
867 __unregister_pernet_operations(ops
);
870 ida_remove(&net_generic_ids
, *ops
->id
);
874 * register_pernet_subsys - register a network namespace subsystem
875 * @ops: pernet operations structure for the subsystem
877 * Register a subsystem which has init and exit functions
878 * that are called when network namespaces are created and
879 * destroyed respectively.
881 * When registered all network namespace init functions are
882 * called for every existing network namespace. Allowing kernel
883 * modules to have a race free view of the set of network namespaces.
885 * When a new network namespace is created all of the init
886 * methods are called in the order in which they were registered.
888 * When a network namespace is destroyed all of the exit methods
889 * are called in the reverse of the order with which they were
892 int register_pernet_subsys(struct pernet_operations
*ops
)
895 mutex_lock(&net_mutex
);
896 error
= register_pernet_operations(first_device
, ops
);
897 mutex_unlock(&net_mutex
);
900 EXPORT_SYMBOL_GPL(register_pernet_subsys
);
903 * unregister_pernet_subsys - unregister a network namespace subsystem
904 * @ops: pernet operations structure to manipulate
906 * Remove the pernet operations structure from the list to be
907 * used when network namespaces are created or destroyed. In
908 * addition run the exit method for all existing network
911 void unregister_pernet_subsys(struct pernet_operations
*ops
)
913 mutex_lock(&net_mutex
);
914 unregister_pernet_operations(ops
);
915 mutex_unlock(&net_mutex
);
917 EXPORT_SYMBOL_GPL(unregister_pernet_subsys
);
920 * register_pernet_device - register a network namespace device
921 * @ops: pernet operations structure for the subsystem
923 * Register a device which has init and exit functions
924 * that are called when network namespaces are created and
925 * destroyed respectively.
927 * When registered all network namespace init functions are
928 * called for every existing network namespace. Allowing kernel
929 * modules to have a race free view of the set of network namespaces.
931 * When a new network namespace is created all of the init
932 * methods are called in the order in which they were registered.
934 * When a network namespace is destroyed all of the exit methods
935 * are called in the reverse of the order with which they were
938 int register_pernet_device(struct pernet_operations
*ops
)
941 mutex_lock(&net_mutex
);
942 error
= register_pernet_operations(&pernet_list
, ops
);
943 if (!error
&& (first_device
== &pernet_list
))
944 first_device
= &ops
->list
;
945 mutex_unlock(&net_mutex
);
948 EXPORT_SYMBOL_GPL(register_pernet_device
);
951 * unregister_pernet_device - unregister a network namespace netdevice
952 * @ops: pernet operations structure to manipulate
954 * Remove the pernet operations structure from the list to be
955 * used when network namespaces are created or destroyed. In
956 * addition run the exit method for all existing network
959 void unregister_pernet_device(struct pernet_operations
*ops
)
961 mutex_lock(&net_mutex
);
962 if (&ops
->list
== first_device
)
963 first_device
= first_device
->next
;
964 unregister_pernet_operations(ops
);
965 mutex_unlock(&net_mutex
);
967 EXPORT_SYMBOL_GPL(unregister_pernet_device
);
970 static struct ns_common
*netns_get(struct task_struct
*task
)
972 struct net
*net
= NULL
;
973 struct nsproxy
*nsproxy
;
976 nsproxy
= task
->nsproxy
;
978 net
= get_net(nsproxy
->net_ns
);
981 return net
? &net
->ns
: NULL
;
984 static inline struct net
*to_net_ns(struct ns_common
*ns
)
986 return container_of(ns
, struct net
, ns
);
989 static void netns_put(struct ns_common
*ns
)
991 put_net(to_net_ns(ns
));
994 static int netns_install(struct nsproxy
*nsproxy
, struct ns_common
*ns
)
996 struct net
*net
= to_net_ns(ns
);
998 if (!ns_capable(net
->user_ns
, CAP_SYS_ADMIN
) ||
999 !ns_capable(current_user_ns(), CAP_SYS_ADMIN
))
1002 put_net(nsproxy
->net_ns
);
1003 nsproxy
->net_ns
= get_net(net
);
1007 const struct proc_ns_operations netns_operations
= {
1009 .type
= CLONE_NEWNET
,
1012 .install
= netns_install
,