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) {
141 ops->exit_batch(net_exit_list);
144 static void ops_free_list(const struct pernet_operations *ops,
145 struct list_head *net_exit_list)
148 if (ops->size && ops->id) {
149 list_for_each_entry(net, net_exit_list, exit_list)
154 /* should be called with nsid_lock held */
155 static int alloc_netid(struct net *net, struct net *peer, int reqid)
157 int min = 0, max = 0;
164 return idr_alloc(&net->netns_ids, peer, min, max, GFP_ATOMIC);
167 /* This function is used by idr_for_each(). If net is equal to peer, the
168 * function returns the id so that idr_for_each() stops. Because we cannot
169 * returns the id 0 (idr_for_each() will not stop), we return the magic value
170 * NET_ID_ZERO (-1) for it.
172 #define NET_ID_ZERO -1
173 static int net_eq_idr(int id, void *net, void *peer)
175 if (net_eq(net, peer))
176 return id ? : NET_ID_ZERO;
180 /* Should be called with nsid_lock held. If a new id is assigned, the bool alloc
181 * is set to true, thus the caller knows that the new id must be notified via
184 static int __peernet2id_alloc(struct net *net, struct net *peer, bool *alloc)
186 int id = idr_for_each(&net->netns_ids, net_eq_idr, peer);
187 bool alloc_it = *alloc;
191 /* Magic value for id 0. */
192 if (id == NET_ID_ZERO)
198 id = alloc_netid(net, peer, -1);
200 return id >= 0 ? id : NETNSA_NSID_NOT_ASSIGNED;
203 return NETNSA_NSID_NOT_ASSIGNED;
206 /* should be called with nsid_lock held */
207 static int __peernet2id(struct net *net, struct net *peer)
211 return __peernet2id_alloc(net, peer, &no);
214 static void rtnl_net_notifyid(struct net *net, int cmd, int id);
215 /* This function returns the id of a peer netns. If no id is assigned, one will
216 * be allocated and returned.
218 int peernet2id_alloc(struct net *net, struct net *peer)
224 if (atomic_read(&net->count) == 0)
225 return NETNSA_NSID_NOT_ASSIGNED;
226 spin_lock_irqsave(&net->nsid_lock, flags);
227 alloc = atomic_read(&peer->count) == 0 ? false : true;
228 id = __peernet2id_alloc(net, peer, &alloc);
229 spin_unlock_irqrestore(&net->nsid_lock, flags);
230 if (alloc && id >= 0)
231 rtnl_net_notifyid(net, RTM_NEWNSID, id);
235 /* This function returns, if assigned, the id of a peer netns. */
236 int peernet2id(struct net *net, struct net *peer)
241 spin_lock_irqsave(&net->nsid_lock, flags);
242 id = __peernet2id(net, peer);
243 spin_unlock_irqrestore(&net->nsid_lock, flags);
246 EXPORT_SYMBOL(peernet2id);
248 /* This function returns true is the peer netns has an id assigned into the
251 bool peernet_has_id(struct net *net, struct net *peer)
253 return peernet2id(net, peer) >= 0;
256 struct net *get_net_ns_by_id(struct net *net, int id)
265 spin_lock_irqsave(&net->nsid_lock, flags);
266 peer = idr_find(&net->netns_ids, id);
268 peer = maybe_get_net(peer);
269 spin_unlock_irqrestore(&net->nsid_lock, flags);
276 * setup_net runs the initializers for the network namespace object.
278 static __net_init int setup_net(struct net *net, struct user_namespace *user_ns)
280 /* Must be called with net_mutex held */
281 const struct pernet_operations *ops, *saved_ops;
283 LIST_HEAD(net_exit_list);
285 atomic_set(&net->count, 1);
286 atomic_set(&net->passive, 1);
287 get_random_bytes(&net->hash_mix, sizeof(u32));
288 net->dev_base_seq = 1;
289 net->user_ns = user_ns;
290 idr_init(&net->netns_ids);
291 spin_lock_init(&net->nsid_lock);
293 list_for_each_entry(ops, &pernet_list, list) {
294 error = ops_init(ops, net);
302 /* Walk through the list backwards calling the exit functions
303 * for the pernet modules whose init functions did not fail.
305 list_add(&net->exit_list, &net_exit_list);
307 list_for_each_entry_continue_reverse(ops, &pernet_list, list)
308 ops_exit_list(ops, &net_exit_list);
311 list_for_each_entry_continue_reverse(ops, &pernet_list, list)
312 ops_free_list(ops, &net_exit_list);
318 static int __net_init net_defaults_init_net(struct net *net)
320 net->core.sysctl_somaxconn = SOMAXCONN;
324 static struct pernet_operations net_defaults_ops = {
325 .init = net_defaults_init_net,
328 static __init int net_defaults_init(void)
330 if (register_pernet_subsys(&net_defaults_ops))
331 panic("Cannot initialize net default settings");
336 core_initcall(net_defaults_init);
339 static struct ucounts *inc_net_namespaces(struct user_namespace *ns)
341 return inc_ucount(ns, current_euid(), UCOUNT_NET_NAMESPACES);
344 static void dec_net_namespaces(struct ucounts *ucounts)
346 dec_ucount(ucounts, UCOUNT_NET_NAMESPACES);
349 static struct kmem_cache *net_cachep;
350 static struct workqueue_struct *netns_wq;
352 static struct net *net_alloc(void)
354 struct net *net = NULL;
355 struct net_generic *ng;
357 ng = net_alloc_generic();
361 net = kmem_cache_zalloc(net_cachep, GFP_KERNEL);
365 rcu_assign_pointer(net->gen, ng);
374 static void net_free(struct net *net)
376 kfree(rcu_access_pointer(net->gen));
377 kmem_cache_free(net_cachep, net);
380 void net_drop_ns(void *p)
383 if (ns && atomic_dec_and_test(&ns->passive))
387 struct net *copy_net_ns(unsigned long flags,
388 struct user_namespace *user_ns, struct net *old_net)
390 struct ucounts *ucounts;
394 if (!(flags & CLONE_NEWNET))
395 return get_net(old_net);
397 ucounts = inc_net_namespaces(user_ns);
399 return ERR_PTR(-ENOSPC);
403 dec_net_namespaces(ucounts);
404 return ERR_PTR(-ENOMEM);
407 get_user_ns(user_ns);
409 mutex_lock(&net_mutex);
410 net->ucounts = ucounts;
411 rv = setup_net(net, user_ns);
414 list_add_tail_rcu(&net->list, &net_namespace_list);
417 mutex_unlock(&net_mutex);
419 dec_net_namespaces(ucounts);
420 put_user_ns(user_ns);
427 static DEFINE_SPINLOCK(cleanup_list_lock);
428 static LIST_HEAD(cleanup_list); /* Must hold cleanup_list_lock to touch */
430 static void cleanup_net(struct work_struct *work)
432 const struct pernet_operations *ops;
433 struct net *net, *tmp;
434 struct list_head net_kill_list;
435 LIST_HEAD(net_exit_list);
437 /* Atomically snapshot the list of namespaces to cleanup */
438 spin_lock_irq(&cleanup_list_lock);
439 list_replace_init(&cleanup_list, &net_kill_list);
440 spin_unlock_irq(&cleanup_list_lock);
442 mutex_lock(&net_mutex);
444 /* Don't let anyone else find us. */
446 list_for_each_entry(net, &net_kill_list, cleanup_list) {
447 list_del_rcu(&net->list);
448 list_add_tail(&net->exit_list, &net_exit_list);
452 spin_lock_irq(&tmp->nsid_lock);
453 id = __peernet2id(tmp, net);
455 idr_remove(&tmp->netns_ids, id);
456 spin_unlock_irq(&tmp->nsid_lock);
458 rtnl_net_notifyid(tmp, RTM_DELNSID, id);
460 spin_lock_irq(&net->nsid_lock);
461 idr_destroy(&net->netns_ids);
462 spin_unlock_irq(&net->nsid_lock);
468 * Another CPU might be rcu-iterating the list, wait for it.
469 * This needs to be before calling the exit() notifiers, so
470 * the rcu_barrier() below isn't sufficient alone.
474 /* Run all of the network namespace exit methods */
475 list_for_each_entry_reverse(ops, &pernet_list, list)
476 ops_exit_list(ops, &net_exit_list);
478 /* Free the net generic variables */
479 list_for_each_entry_reverse(ops, &pernet_list, list)
480 ops_free_list(ops, &net_exit_list);
482 mutex_unlock(&net_mutex);
484 /* Ensure there are no outstanding rcu callbacks using this
489 /* Finally it is safe to free my network namespace structure */
490 list_for_each_entry_safe(net, tmp, &net_exit_list, exit_list) {
491 list_del_init(&net->exit_list);
492 dec_net_namespaces(net->ucounts);
493 put_user_ns(net->user_ns);
497 static DECLARE_WORK(net_cleanup_work, cleanup_net);
499 void __put_net(struct net *net)
501 /* Cleanup the network namespace in process context */
504 spin_lock_irqsave(&cleanup_list_lock, flags);
505 list_add(&net->cleanup_list, &cleanup_list);
506 spin_unlock_irqrestore(&cleanup_list_lock, flags);
508 queue_work(netns_wq, &net_cleanup_work);
510 EXPORT_SYMBOL_GPL(__put_net);
512 struct net *get_net_ns_by_fd(int fd)
515 struct ns_common *ns;
518 file = proc_ns_fget(fd);
520 return ERR_CAST(file);
522 ns = get_proc_ns(file_inode(file));
523 if (ns->ops == &netns_operations)
524 net = get_net(container_of(ns, struct net, ns));
526 net = ERR_PTR(-EINVAL);
533 struct net *get_net_ns_by_fd(int fd)
535 return ERR_PTR(-EINVAL);
538 EXPORT_SYMBOL_GPL(get_net_ns_by_fd);
540 struct net *get_net_ns_by_pid(pid_t pid)
542 struct task_struct *tsk;
545 /* Lookup the network namespace */
546 net = ERR_PTR(-ESRCH);
548 tsk = find_task_by_vpid(pid);
550 struct nsproxy *nsproxy;
552 nsproxy = tsk->nsproxy;
554 net = get_net(nsproxy->net_ns);
560 EXPORT_SYMBOL_GPL(get_net_ns_by_pid);
562 static __net_init int net_ns_net_init(struct net *net)
565 net->ns.ops = &netns_operations;
567 return ns_alloc_inum(&net->ns);
570 static __net_exit void net_ns_net_exit(struct net *net)
572 ns_free_inum(&net->ns);
575 static struct pernet_operations __net_initdata net_ns_ops = {
576 .init = net_ns_net_init,
577 .exit = net_ns_net_exit,
580 static const struct nla_policy rtnl_net_policy[NETNSA_MAX + 1] = {
581 [NETNSA_NONE] = { .type = NLA_UNSPEC },
582 [NETNSA_NSID] = { .type = NLA_S32 },
583 [NETNSA_PID] = { .type = NLA_U32 },
584 [NETNSA_FD] = { .type = NLA_U32 },
587 static int rtnl_net_newid(struct sk_buff *skb, struct nlmsghdr *nlh)
589 struct net *net = sock_net(skb->sk);
590 struct nlattr *tb[NETNSA_MAX + 1];
595 err = nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, NETNSA_MAX,
599 if (!tb[NETNSA_NSID])
601 nsid = nla_get_s32(tb[NETNSA_NSID]);
604 peer = get_net_ns_by_pid(nla_get_u32(tb[NETNSA_PID]));
605 else if (tb[NETNSA_FD])
606 peer = get_net_ns_by_fd(nla_get_u32(tb[NETNSA_FD]));
610 return PTR_ERR(peer);
612 spin_lock_irqsave(&net->nsid_lock, flags);
613 if (__peernet2id(net, peer) >= 0) {
614 spin_unlock_irqrestore(&net->nsid_lock, flags);
619 err = alloc_netid(net, peer, nsid);
620 spin_unlock_irqrestore(&net->nsid_lock, flags);
622 rtnl_net_notifyid(net, RTM_NEWNSID, err);
630 static int rtnl_net_get_size(void)
632 return NLMSG_ALIGN(sizeof(struct rtgenmsg))
633 + nla_total_size(sizeof(s32)) /* NETNSA_NSID */
637 static int rtnl_net_fill(struct sk_buff *skb, u32 portid, u32 seq, int flags,
638 int cmd, struct net *net, int nsid)
640 struct nlmsghdr *nlh;
641 struct rtgenmsg *rth;
643 nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rth), flags);
647 rth = nlmsg_data(nlh);
648 rth->rtgen_family = AF_UNSPEC;
650 if (nla_put_s32(skb, NETNSA_NSID, nsid))
651 goto nla_put_failure;
657 nlmsg_cancel(skb, nlh);
661 static int rtnl_net_getid(struct sk_buff *skb, struct nlmsghdr *nlh)
663 struct net *net = sock_net(skb->sk);
664 struct nlattr *tb[NETNSA_MAX + 1];
669 err = nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, NETNSA_MAX,
674 peer = get_net_ns_by_pid(nla_get_u32(tb[NETNSA_PID]));
675 else if (tb[NETNSA_FD])
676 peer = get_net_ns_by_fd(nla_get_u32(tb[NETNSA_FD]));
681 return PTR_ERR(peer);
683 msg = nlmsg_new(rtnl_net_get_size(), GFP_KERNEL);
689 id = peernet2id(net, peer);
690 err = rtnl_net_fill(msg, NETLINK_CB(skb).portid, nlh->nlmsg_seq, 0,
691 RTM_NEWNSID, net, id);
695 err = rtnl_unicast(msg, net, NETLINK_CB(skb).portid);
705 struct rtnl_net_dump_cb {
708 struct netlink_callback *cb;
713 static int rtnl_net_dumpid_one(int id, void *peer, void *data)
715 struct rtnl_net_dump_cb *net_cb = (struct rtnl_net_dump_cb *)data;
718 if (net_cb->idx < net_cb->s_idx)
721 ret = rtnl_net_fill(net_cb->skb, NETLINK_CB(net_cb->cb->skb).portid,
722 net_cb->cb->nlh->nlmsg_seq, NLM_F_MULTI,
723 RTM_NEWNSID, net_cb->net, id);
732 static int rtnl_net_dumpid(struct sk_buff *skb, struct netlink_callback *cb)
734 struct net *net = sock_net(skb->sk);
735 struct rtnl_net_dump_cb net_cb = {
740 .s_idx = cb->args[0],
744 spin_lock_irqsave(&net->nsid_lock, flags);
745 idr_for_each(&net->netns_ids, rtnl_net_dumpid_one, &net_cb);
746 spin_unlock_irqrestore(&net->nsid_lock, flags);
748 cb->args[0] = net_cb.idx;
752 static void rtnl_net_notifyid(struct net *net, int cmd, int id)
757 msg = nlmsg_new(rtnl_net_get_size(), GFP_KERNEL);
761 err = rtnl_net_fill(msg, 0, 0, 0, cmd, net, id);
765 rtnl_notify(msg, net, 0, RTNLGRP_NSID, NULL, 0);
771 rtnl_set_sk_err(net, RTNLGRP_NSID, err);
774 static int __init net_ns_init(void)
776 struct net_generic *ng;
779 net_cachep = kmem_cache_create("net_namespace", sizeof(struct net),
783 /* Create workqueue for cleanup */
784 netns_wq = create_singlethread_workqueue("netns");
786 panic("Could not create netns workq");
789 ng = net_alloc_generic();
791 panic("Could not allocate generic netns");
793 rcu_assign_pointer(init_net.gen, ng);
795 mutex_lock(&net_mutex);
796 if (setup_net(&init_net, &init_user_ns))
797 panic("Could not setup the initial network namespace");
799 init_net_initialized = true;
802 list_add_tail_rcu(&init_net.list, &net_namespace_list);
805 mutex_unlock(&net_mutex);
807 if (register_pernet_subsys(&net_ns_ops))
808 panic("Could not register network namespace subsystems");
810 rtnl_register(PF_UNSPEC, RTM_NEWNSID, rtnl_net_newid, NULL, NULL);
811 rtnl_register(PF_UNSPEC, RTM_GETNSID, rtnl_net_getid, rtnl_net_dumpid,
817 pure_initcall(net_ns_init);
820 static int __register_pernet_operations(struct list_head *list,
821 struct pernet_operations *ops)
825 LIST_HEAD(net_exit_list);
827 list_add_tail(&ops->list, list);
828 if (ops->init || (ops->id && ops->size)) {
830 error = ops_init(ops, net);
833 list_add_tail(&net->exit_list, &net_exit_list);
839 /* If I have an error cleanup all namespaces I initialized */
840 list_del(&ops->list);
841 ops_exit_list(ops, &net_exit_list);
842 ops_free_list(ops, &net_exit_list);
846 static void __unregister_pernet_operations(struct pernet_operations *ops)
849 LIST_HEAD(net_exit_list);
851 list_del(&ops->list);
853 list_add_tail(&net->exit_list, &net_exit_list);
854 ops_exit_list(ops, &net_exit_list);
855 ops_free_list(ops, &net_exit_list);
860 static int __register_pernet_operations(struct list_head *list,
861 struct pernet_operations *ops)
863 if (!init_net_initialized) {
864 list_add_tail(&ops->list, list);
868 return ops_init(ops, &init_net);
871 static void __unregister_pernet_operations(struct pernet_operations *ops)
873 if (!init_net_initialized) {
874 list_del(&ops->list);
876 LIST_HEAD(net_exit_list);
877 list_add(&init_net.exit_list, &net_exit_list);
878 ops_exit_list(ops, &net_exit_list);
879 ops_free_list(ops, &net_exit_list);
883 #endif /* CONFIG_NET_NS */
885 static DEFINE_IDA(net_generic_ids);
887 static int register_pernet_operations(struct list_head *list,
888 struct pernet_operations *ops)
894 error = ida_get_new_above(&net_generic_ids, 1, ops->id);
896 if (error == -EAGAIN) {
897 ida_pre_get(&net_generic_ids, GFP_KERNEL);
902 max_gen_ptrs = max_t(unsigned int, max_gen_ptrs, *ops->id);
904 error = __register_pernet_operations(list, ops);
908 ida_remove(&net_generic_ids, *ops->id);
914 static void unregister_pernet_operations(struct pernet_operations *ops)
917 __unregister_pernet_operations(ops);
920 ida_remove(&net_generic_ids, *ops->id);
924 * register_pernet_subsys - register a network namespace subsystem
925 * @ops: pernet operations structure for the subsystem
927 * Register a subsystem which has init and exit functions
928 * that are called when network namespaces are created and
929 * destroyed respectively.
931 * When registered all network namespace init functions are
932 * called for every existing network namespace. Allowing kernel
933 * modules to have a race free view of the set of network namespaces.
935 * When a new network namespace is created all of the init
936 * methods are called in the order in which they were registered.
938 * When a network namespace is destroyed all of the exit methods
939 * are called in the reverse of the order with which they were
942 int register_pernet_subsys(struct pernet_operations *ops)
945 mutex_lock(&net_mutex);
946 error = register_pernet_operations(first_device, ops);
947 mutex_unlock(&net_mutex);
950 EXPORT_SYMBOL_GPL(register_pernet_subsys);
953 * unregister_pernet_subsys - unregister a network namespace subsystem
954 * @ops: pernet operations structure to manipulate
956 * Remove the pernet operations structure from the list to be
957 * used when network namespaces are created or destroyed. In
958 * addition run the exit method for all existing network
961 void unregister_pernet_subsys(struct pernet_operations *ops)
963 mutex_lock(&net_mutex);
964 unregister_pernet_operations(ops);
965 mutex_unlock(&net_mutex);
967 EXPORT_SYMBOL_GPL(unregister_pernet_subsys);
970 * register_pernet_device - register a network namespace device
971 * @ops: pernet operations structure for the subsystem
973 * Register a device which has init and exit functions
974 * that are called when network namespaces are created and
975 * destroyed respectively.
977 * When registered all network namespace init functions are
978 * called for every existing network namespace. Allowing kernel
979 * modules to have a race free view of the set of network namespaces.
981 * When a new network namespace is created all of the init
982 * methods are called in the order in which they were registered.
984 * When a network namespace is destroyed all of the exit methods
985 * are called in the reverse of the order with which they were
988 int register_pernet_device(struct pernet_operations *ops)
991 mutex_lock(&net_mutex);
992 error = register_pernet_operations(&pernet_list, ops);
993 if (!error && (first_device == &pernet_list))
994 first_device = &ops->list;
995 mutex_unlock(&net_mutex);
998 EXPORT_SYMBOL_GPL(register_pernet_device);
1001 * unregister_pernet_device - unregister a network namespace netdevice
1002 * @ops: pernet operations structure to manipulate
1004 * Remove the pernet operations structure from the list to be
1005 * used when network namespaces are created or destroyed. In
1006 * addition run the exit method for all existing network
1009 void unregister_pernet_device(struct pernet_operations *ops)
1011 mutex_lock(&net_mutex);
1012 if (&ops->list == first_device)
1013 first_device = first_device->next;
1014 unregister_pernet_operations(ops);
1015 mutex_unlock(&net_mutex);
1017 EXPORT_SYMBOL_GPL(unregister_pernet_device);
1019 #ifdef CONFIG_NET_NS
1020 static struct ns_common *netns_get(struct task_struct *task)
1022 struct net *net = NULL;
1023 struct nsproxy *nsproxy;
1026 nsproxy = task->nsproxy;
1028 net = get_net(nsproxy->net_ns);
1031 return net ? &net->ns : NULL;
1034 static inline struct net *to_net_ns(struct ns_common *ns)
1036 return container_of(ns, struct net, ns);
1039 static void netns_put(struct ns_common *ns)
1041 put_net(to_net_ns(ns));
1044 static int netns_install(struct nsproxy *nsproxy, struct ns_common *ns)
1046 struct net *net = to_net_ns(ns);
1048 if (!ns_capable(net->user_ns, CAP_SYS_ADMIN) ||
1049 !ns_capable(current_user_ns(), CAP_SYS_ADMIN))
1052 put_net(nsproxy->net_ns);
1053 nsproxy->net_ns = get_net(net);
1057 static struct user_namespace *netns_owner(struct ns_common *ns)
1059 return to_net_ns(ns)->user_ns;
1062 const struct proc_ns_operations netns_operations = {
1064 .type = CLONE_NEWNET,
1067 .install = netns_install,
1068 .owner = netns_owner,