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>
19 #include <linux/sched/task.h>
22 #include <net/netlink.h>
23 #include <net/net_namespace.h>
24 #include <net/netns/generic.h>
27 * Our network namespace constructor/destructor lists
30 static LIST_HEAD(pernet_list);
31 static struct list_head *first_device = &pernet_list;
32 DEFINE_MUTEX(net_mutex);
34 LIST_HEAD(net_namespace_list);
35 EXPORT_SYMBOL_GPL(net_namespace_list);
37 struct net init_net = {
38 .count = ATOMIC_INIT(1),
39 .dev_base_head = LIST_HEAD_INIT(init_net.dev_base_head),
41 EXPORT_SYMBOL(init_net);
43 static bool init_net_initialized;
45 #define MIN_PERNET_OPS_ID \
46 ((sizeof(struct net_generic) + sizeof(void *) - 1) / sizeof(void *))
48 #define INITIAL_NET_GEN_PTRS 13 /* +1 for len +2 for rcu_head */
50 static unsigned int max_gen_ptrs = INITIAL_NET_GEN_PTRS;
52 static struct net_generic *net_alloc_generic(void)
54 struct net_generic *ng;
55 unsigned int generic_size = offsetof(struct net_generic, ptr[max_gen_ptrs]);
57 ng = kzalloc(generic_size, GFP_KERNEL);
59 ng->s.len = max_gen_ptrs;
64 static int net_assign_generic(struct net *net, unsigned int id, void *data)
66 struct net_generic *ng, *old_ng;
68 BUG_ON(!mutex_is_locked(&net_mutex));
69 BUG_ON(id < MIN_PERNET_OPS_ID);
71 old_ng = rcu_dereference_protected(net->gen,
72 lockdep_is_held(&net_mutex));
73 if (old_ng->s.len > id) {
74 old_ng->ptr[id] = data;
78 ng = net_alloc_generic();
83 * Some synchronisation notes:
85 * The net_generic explores the net->gen array inside rcu
86 * read section. Besides once set the net->gen->ptr[x]
87 * pointer never changes (see rules in netns/generic.h).
89 * That said, we simply duplicate this array and schedule
90 * the old copy for kfree after a grace period.
93 memcpy(&ng->ptr[MIN_PERNET_OPS_ID], &old_ng->ptr[MIN_PERNET_OPS_ID],
94 (old_ng->s.len - MIN_PERNET_OPS_ID) * sizeof(void *));
97 rcu_assign_pointer(net->gen, ng);
98 kfree_rcu(old_ng, s.rcu);
102 static int ops_init(const struct pernet_operations *ops, struct net *net)
107 if (ops->id && ops->size) {
108 data = kzalloc(ops->size, GFP_KERNEL);
112 err = net_assign_generic(net, *ops->id, data);
118 err = ops->init(net);
129 static void ops_free(const struct pernet_operations *ops, struct net *net)
131 if (ops->id && ops->size) {
132 kfree(net_generic(net, *ops->id));
136 static void ops_exit_list(const struct pernet_operations *ops,
137 struct list_head *net_exit_list)
141 list_for_each_entry(net, net_exit_list, exit_list)
145 ops->exit_batch(net_exit_list);
148 static void ops_free_list(const struct pernet_operations *ops,
149 struct list_head *net_exit_list)
152 if (ops->size && ops->id) {
153 list_for_each_entry(net, net_exit_list, exit_list)
158 /* should be called with nsid_lock held */
159 static int alloc_netid(struct net *net, struct net *peer, int reqid)
161 int min = 0, max = 0;
168 return idr_alloc(&net->netns_ids, peer, min, max, GFP_ATOMIC);
171 /* This function is used by idr_for_each(). If net is equal to peer, the
172 * function returns the id so that idr_for_each() stops. Because we cannot
173 * returns the id 0 (idr_for_each() will not stop), we return the magic value
174 * NET_ID_ZERO (-1) for it.
176 #define NET_ID_ZERO -1
177 static int net_eq_idr(int id, void *net, void *peer)
179 if (net_eq(net, peer))
180 return id ? : NET_ID_ZERO;
184 /* Should be called with nsid_lock held. If a new id is assigned, the bool alloc
185 * is set to true, thus the caller knows that the new id must be notified via
188 static int __peernet2id_alloc(struct net *net, struct net *peer, bool *alloc)
190 int id = idr_for_each(&net->netns_ids, net_eq_idr, peer);
191 bool alloc_it = *alloc;
195 /* Magic value for id 0. */
196 if (id == NET_ID_ZERO)
202 id = alloc_netid(net, peer, -1);
204 return id >= 0 ? id : NETNSA_NSID_NOT_ASSIGNED;
207 return NETNSA_NSID_NOT_ASSIGNED;
210 /* should be called with nsid_lock held */
211 static int __peernet2id(struct net *net, struct net *peer)
215 return __peernet2id_alloc(net, peer, &no);
218 static void rtnl_net_notifyid(struct net *net, int cmd, int id);
219 /* This function returns the id of a peer netns. If no id is assigned, one will
220 * be allocated and returned.
222 int peernet2id_alloc(struct net *net, struct net *peer)
227 if (atomic_read(&net->count) == 0)
228 return NETNSA_NSID_NOT_ASSIGNED;
229 spin_lock_bh(&net->nsid_lock);
230 alloc = atomic_read(&peer->count) == 0 ? false : true;
231 id = __peernet2id_alloc(net, peer, &alloc);
232 spin_unlock_bh(&net->nsid_lock);
233 if (alloc && id >= 0)
234 rtnl_net_notifyid(net, RTM_NEWNSID, id);
238 /* This function returns, if assigned, the id of a peer netns. */
239 int peernet2id(struct net *net, struct net *peer)
243 spin_lock_bh(&net->nsid_lock);
244 id = __peernet2id(net, peer);
245 spin_unlock_bh(&net->nsid_lock);
248 EXPORT_SYMBOL(peernet2id);
250 /* This function returns true is the peer netns has an id assigned into the
253 bool peernet_has_id(struct net *net, struct net *peer)
255 return peernet2id(net, peer) >= 0;
258 struct net *get_net_ns_by_id(struct net *net, int id)
266 spin_lock_bh(&net->nsid_lock);
267 peer = idr_find(&net->netns_ids, id);
270 spin_unlock_bh(&net->nsid_lock);
277 * setup_net runs the initializers for the network namespace object.
279 static __net_init int setup_net(struct net *net, struct user_namespace *user_ns)
281 /* Must be called with net_mutex held */
282 const struct pernet_operations *ops, *saved_ops;
284 LIST_HEAD(net_exit_list);
286 atomic_set(&net->count, 1);
287 atomic_set(&net->passive, 1);
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);
320 static struct ucounts *inc_net_namespaces(struct user_namespace *ns)
322 return inc_ucount(ns, current_euid(), UCOUNT_NET_NAMESPACES);
325 static void dec_net_namespaces(struct ucounts *ucounts)
327 dec_ucount(ucounts, UCOUNT_NET_NAMESPACES);
330 static struct kmem_cache *net_cachep;
331 static struct workqueue_struct *netns_wq;
333 static struct net *net_alloc(void)
335 struct net *net = NULL;
336 struct net_generic *ng;
338 ng = net_alloc_generic();
342 net = kmem_cache_zalloc(net_cachep, GFP_KERNEL);
346 rcu_assign_pointer(net->gen, ng);
355 static void net_free(struct net *net)
357 kfree(rcu_access_pointer(net->gen));
358 kmem_cache_free(net_cachep, net);
361 void net_drop_ns(void *p)
364 if (ns && atomic_dec_and_test(&ns->passive))
368 struct net *copy_net_ns(unsigned long flags,
369 struct user_namespace *user_ns, struct net *old_net)
371 struct ucounts *ucounts;
375 if (!(flags & CLONE_NEWNET))
376 return get_net(old_net);
378 ucounts = inc_net_namespaces(user_ns);
380 return ERR_PTR(-ENOSPC);
384 dec_net_namespaces(ucounts);
385 return ERR_PTR(-ENOMEM);
388 get_user_ns(user_ns);
390 rv = mutex_lock_killable(&net_mutex);
393 dec_net_namespaces(ucounts);
394 put_user_ns(user_ns);
398 net->ucounts = ucounts;
399 rv = setup_net(net, user_ns);
402 list_add_tail_rcu(&net->list, &net_namespace_list);
405 mutex_unlock(&net_mutex);
407 dec_net_namespaces(ucounts);
408 put_user_ns(user_ns);
415 static DEFINE_SPINLOCK(cleanup_list_lock);
416 static LIST_HEAD(cleanup_list); /* Must hold cleanup_list_lock to touch */
418 static void cleanup_net(struct work_struct *work)
420 const struct pernet_operations *ops;
421 struct net *net, *tmp;
422 struct list_head net_kill_list;
423 LIST_HEAD(net_exit_list);
425 /* Atomically snapshot the list of namespaces to cleanup */
426 spin_lock_irq(&cleanup_list_lock);
427 list_replace_init(&cleanup_list, &net_kill_list);
428 spin_unlock_irq(&cleanup_list_lock);
430 mutex_lock(&net_mutex);
432 /* Don't let anyone else find us. */
434 list_for_each_entry(net, &net_kill_list, cleanup_list) {
435 list_del_rcu(&net->list);
436 list_add_tail(&net->exit_list, &net_exit_list);
440 spin_lock_bh(&tmp->nsid_lock);
441 id = __peernet2id(tmp, net);
443 idr_remove(&tmp->netns_ids, id);
444 spin_unlock_bh(&tmp->nsid_lock);
446 rtnl_net_notifyid(tmp, RTM_DELNSID, id);
448 spin_lock_bh(&net->nsid_lock);
449 idr_destroy(&net->netns_ids);
450 spin_unlock_bh(&net->nsid_lock);
456 * Another CPU might be rcu-iterating the list, wait for it.
457 * This needs to be before calling the exit() notifiers, so
458 * the rcu_barrier() below isn't sufficient alone.
462 /* Run all of the network namespace exit methods */
463 list_for_each_entry_reverse(ops, &pernet_list, list)
464 ops_exit_list(ops, &net_exit_list);
466 /* Free the net generic variables */
467 list_for_each_entry_reverse(ops, &pernet_list, list)
468 ops_free_list(ops, &net_exit_list);
470 mutex_unlock(&net_mutex);
472 /* Ensure there are no outstanding rcu callbacks using this
477 /* Finally it is safe to free my network namespace structure */
478 list_for_each_entry_safe(net, tmp, &net_exit_list, exit_list) {
479 list_del_init(&net->exit_list);
480 dec_net_namespaces(net->ucounts);
481 put_user_ns(net->user_ns);
485 static DECLARE_WORK(net_cleanup_work, cleanup_net);
487 void __put_net(struct net *net)
489 /* Cleanup the network namespace in process context */
492 spin_lock_irqsave(&cleanup_list_lock, flags);
493 list_add(&net->cleanup_list, &cleanup_list);
494 spin_unlock_irqrestore(&cleanup_list_lock, flags);
496 queue_work(netns_wq, &net_cleanup_work);
498 EXPORT_SYMBOL_GPL(__put_net);
500 struct net *get_net_ns_by_fd(int fd)
503 struct ns_common *ns;
506 file = proc_ns_fget(fd);
508 return ERR_CAST(file);
510 ns = get_proc_ns(file_inode(file));
511 if (ns->ops == &netns_operations)
512 net = get_net(container_of(ns, struct net, ns));
514 net = ERR_PTR(-EINVAL);
521 struct net *get_net_ns_by_fd(int fd)
523 return ERR_PTR(-EINVAL);
526 EXPORT_SYMBOL_GPL(get_net_ns_by_fd);
528 struct net *get_net_ns_by_pid(pid_t pid)
530 struct task_struct *tsk;
533 /* Lookup the network namespace */
534 net = ERR_PTR(-ESRCH);
536 tsk = find_task_by_vpid(pid);
538 struct nsproxy *nsproxy;
540 nsproxy = tsk->nsproxy;
542 net = get_net(nsproxy->net_ns);
548 EXPORT_SYMBOL_GPL(get_net_ns_by_pid);
550 static __net_init int net_ns_net_init(struct net *net)
553 net->ns.ops = &netns_operations;
555 return ns_alloc_inum(&net->ns);
558 static __net_exit void net_ns_net_exit(struct net *net)
560 ns_free_inum(&net->ns);
563 static struct pernet_operations __net_initdata net_ns_ops = {
564 .init = net_ns_net_init,
565 .exit = net_ns_net_exit,
568 static const struct nla_policy rtnl_net_policy[NETNSA_MAX + 1] = {
569 [NETNSA_NONE] = { .type = NLA_UNSPEC },
570 [NETNSA_NSID] = { .type = NLA_S32 },
571 [NETNSA_PID] = { .type = NLA_U32 },
572 [NETNSA_FD] = { .type = NLA_U32 },
575 static int rtnl_net_newid(struct sk_buff *skb, struct nlmsghdr *nlh,
576 struct netlink_ext_ack *extack)
578 struct net *net = sock_net(skb->sk);
579 struct nlattr *tb[NETNSA_MAX + 1];
583 err = nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, NETNSA_MAX,
584 rtnl_net_policy, extack);
587 if (!tb[NETNSA_NSID])
589 nsid = nla_get_s32(tb[NETNSA_NSID]);
592 peer = get_net_ns_by_pid(nla_get_u32(tb[NETNSA_PID]));
593 else if (tb[NETNSA_FD])
594 peer = get_net_ns_by_fd(nla_get_u32(tb[NETNSA_FD]));
598 return PTR_ERR(peer);
600 spin_lock_bh(&net->nsid_lock);
601 if (__peernet2id(net, peer) >= 0) {
602 spin_unlock_bh(&net->nsid_lock);
607 err = alloc_netid(net, peer, nsid);
608 spin_unlock_bh(&net->nsid_lock);
610 rtnl_net_notifyid(net, RTM_NEWNSID, err);
618 static int rtnl_net_get_size(void)
620 return NLMSG_ALIGN(sizeof(struct rtgenmsg))
621 + nla_total_size(sizeof(s32)) /* NETNSA_NSID */
625 static int rtnl_net_fill(struct sk_buff *skb, u32 portid, u32 seq, int flags,
626 int cmd, struct net *net, int nsid)
628 struct nlmsghdr *nlh;
629 struct rtgenmsg *rth;
631 nlh = nlmsg_put(skb, portid, seq, cmd, sizeof(*rth), flags);
635 rth = nlmsg_data(nlh);
636 rth->rtgen_family = AF_UNSPEC;
638 if (nla_put_s32(skb, NETNSA_NSID, nsid))
639 goto nla_put_failure;
645 nlmsg_cancel(skb, nlh);
649 static int rtnl_net_getid(struct sk_buff *skb, struct nlmsghdr *nlh,
650 struct netlink_ext_ack *extack)
652 struct net *net = sock_net(skb->sk);
653 struct nlattr *tb[NETNSA_MAX + 1];
658 err = nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, NETNSA_MAX,
659 rtnl_net_policy, extack);
663 peer = get_net_ns_by_pid(nla_get_u32(tb[NETNSA_PID]));
664 else if (tb[NETNSA_FD])
665 peer = get_net_ns_by_fd(nla_get_u32(tb[NETNSA_FD]));
670 return PTR_ERR(peer);
672 msg = nlmsg_new(rtnl_net_get_size(), GFP_KERNEL);
678 id = peernet2id(net, peer);
679 err = rtnl_net_fill(msg, NETLINK_CB(skb).portid, nlh->nlmsg_seq, 0,
680 RTM_NEWNSID, net, id);
684 err = rtnl_unicast(msg, net, NETLINK_CB(skb).portid);
694 struct rtnl_net_dump_cb {
697 struct netlink_callback *cb;
702 static int rtnl_net_dumpid_one(int id, void *peer, void *data)
704 struct rtnl_net_dump_cb *net_cb = (struct rtnl_net_dump_cb *)data;
707 if (net_cb->idx < net_cb->s_idx)
710 ret = rtnl_net_fill(net_cb->skb, NETLINK_CB(net_cb->cb->skb).portid,
711 net_cb->cb->nlh->nlmsg_seq, NLM_F_MULTI,
712 RTM_NEWNSID, net_cb->net, id);
721 static int rtnl_net_dumpid(struct sk_buff *skb, struct netlink_callback *cb)
723 struct net *net = sock_net(skb->sk);
724 struct rtnl_net_dump_cb net_cb = {
729 .s_idx = cb->args[0],
732 spin_lock_bh(&net->nsid_lock);
733 idr_for_each(&net->netns_ids, rtnl_net_dumpid_one, &net_cb);
734 spin_unlock_bh(&net->nsid_lock);
736 cb->args[0] = net_cb.idx;
740 static void rtnl_net_notifyid(struct net *net, int cmd, int id)
745 msg = nlmsg_new(rtnl_net_get_size(), GFP_KERNEL);
749 err = rtnl_net_fill(msg, 0, 0, 0, cmd, net, id);
753 rtnl_notify(msg, net, 0, RTNLGRP_NSID, NULL, 0);
759 rtnl_set_sk_err(net, RTNLGRP_NSID, err);
762 static int __init net_ns_init(void)
764 struct net_generic *ng;
767 net_cachep = kmem_cache_create("net_namespace", sizeof(struct net),
771 /* Create workqueue for cleanup */
772 netns_wq = create_singlethread_workqueue("netns");
774 panic("Could not create netns workq");
777 ng = net_alloc_generic();
779 panic("Could not allocate generic netns");
781 rcu_assign_pointer(init_net.gen, ng);
783 mutex_lock(&net_mutex);
784 if (setup_net(&init_net, &init_user_ns))
785 panic("Could not setup the initial network namespace");
787 init_net_initialized = true;
790 list_add_tail_rcu(&init_net.list, &net_namespace_list);
793 mutex_unlock(&net_mutex);
795 register_pernet_subsys(&net_ns_ops);
797 rtnl_register(PF_UNSPEC, RTM_NEWNSID, rtnl_net_newid, NULL, NULL);
798 rtnl_register(PF_UNSPEC, RTM_GETNSID, rtnl_net_getid, rtnl_net_dumpid,
804 pure_initcall(net_ns_init);
807 static int __register_pernet_operations(struct list_head *list,
808 struct pernet_operations *ops)
812 LIST_HEAD(net_exit_list);
814 list_add_tail(&ops->list, list);
815 if (ops->init || (ops->id && ops->size)) {
817 error = ops_init(ops, net);
820 list_add_tail(&net->exit_list, &net_exit_list);
826 /* If I have an error cleanup all namespaces I initialized */
827 list_del(&ops->list);
828 ops_exit_list(ops, &net_exit_list);
829 ops_free_list(ops, &net_exit_list);
833 static void __unregister_pernet_operations(struct pernet_operations *ops)
836 LIST_HEAD(net_exit_list);
838 list_del(&ops->list);
840 list_add_tail(&net->exit_list, &net_exit_list);
841 ops_exit_list(ops, &net_exit_list);
842 ops_free_list(ops, &net_exit_list);
847 static int __register_pernet_operations(struct list_head *list,
848 struct pernet_operations *ops)
850 if (!init_net_initialized) {
851 list_add_tail(&ops->list, list);
855 return ops_init(ops, &init_net);
858 static void __unregister_pernet_operations(struct pernet_operations *ops)
860 if (!init_net_initialized) {
861 list_del(&ops->list);
863 LIST_HEAD(net_exit_list);
864 list_add(&init_net.exit_list, &net_exit_list);
865 ops_exit_list(ops, &net_exit_list);
866 ops_free_list(ops, &net_exit_list);
870 #endif /* CONFIG_NET_NS */
872 static DEFINE_IDA(net_generic_ids);
874 static int register_pernet_operations(struct list_head *list,
875 struct pernet_operations *ops)
881 error = ida_get_new_above(&net_generic_ids, MIN_PERNET_OPS_ID, ops->id);
883 if (error == -EAGAIN) {
884 ida_pre_get(&net_generic_ids, GFP_KERNEL);
889 max_gen_ptrs = max(max_gen_ptrs, *ops->id + 1);
891 error = __register_pernet_operations(list, ops);
895 ida_remove(&net_generic_ids, *ops->id);
901 static void unregister_pernet_operations(struct pernet_operations *ops)
904 __unregister_pernet_operations(ops);
907 ida_remove(&net_generic_ids, *ops->id);
911 * register_pernet_subsys - register a network namespace subsystem
912 * @ops: pernet operations structure for the subsystem
914 * Register a subsystem which has init and exit functions
915 * that are called when network namespaces are created and
916 * destroyed respectively.
918 * When registered all network namespace init functions are
919 * called for every existing network namespace. Allowing kernel
920 * modules to have a race free view of the set of network namespaces.
922 * When a new network namespace is created all of the init
923 * methods are called in the order in which they were registered.
925 * When a network namespace is destroyed all of the exit methods
926 * are called in the reverse of the order with which they were
929 int register_pernet_subsys(struct pernet_operations *ops)
932 mutex_lock(&net_mutex);
933 error = register_pernet_operations(first_device, ops);
934 mutex_unlock(&net_mutex);
937 EXPORT_SYMBOL_GPL(register_pernet_subsys);
940 * unregister_pernet_subsys - unregister a network namespace subsystem
941 * @ops: pernet operations structure to manipulate
943 * Remove the pernet operations structure from the list to be
944 * used when network namespaces are created or destroyed. In
945 * addition run the exit method for all existing network
948 void unregister_pernet_subsys(struct pernet_operations *ops)
950 mutex_lock(&net_mutex);
951 unregister_pernet_operations(ops);
952 mutex_unlock(&net_mutex);
954 EXPORT_SYMBOL_GPL(unregister_pernet_subsys);
957 * register_pernet_device - register a network namespace device
958 * @ops: pernet operations structure for the subsystem
960 * Register a device which has init and exit functions
961 * that are called when network namespaces are created and
962 * destroyed respectively.
964 * When registered all network namespace init functions are
965 * called for every existing network namespace. Allowing kernel
966 * modules to have a race free view of the set of network namespaces.
968 * When a new network namespace is created all of the init
969 * methods are called in the order in which they were registered.
971 * When a network namespace is destroyed all of the exit methods
972 * are called in the reverse of the order with which they were
975 int register_pernet_device(struct pernet_operations *ops)
978 mutex_lock(&net_mutex);
979 error = register_pernet_operations(&pernet_list, ops);
980 if (!error && (first_device == &pernet_list))
981 first_device = &ops->list;
982 mutex_unlock(&net_mutex);
985 EXPORT_SYMBOL_GPL(register_pernet_device);
988 * unregister_pernet_device - unregister a network namespace netdevice
989 * @ops: pernet operations structure to manipulate
991 * Remove the pernet operations structure from the list to be
992 * used when network namespaces are created or destroyed. In
993 * addition run the exit method for all existing network
996 void unregister_pernet_device(struct pernet_operations *ops)
998 mutex_lock(&net_mutex);
999 if (&ops->list == first_device)
1000 first_device = first_device->next;
1001 unregister_pernet_operations(ops);
1002 mutex_unlock(&net_mutex);
1004 EXPORT_SYMBOL_GPL(unregister_pernet_device);
1006 #ifdef CONFIG_NET_NS
1007 static struct ns_common *netns_get(struct task_struct *task)
1009 struct net *net = NULL;
1010 struct nsproxy *nsproxy;
1013 nsproxy = task->nsproxy;
1015 net = get_net(nsproxy->net_ns);
1018 return net ? &net->ns : NULL;
1021 static inline struct net *to_net_ns(struct ns_common *ns)
1023 return container_of(ns, struct net, ns);
1026 static void netns_put(struct ns_common *ns)
1028 put_net(to_net_ns(ns));
1031 static int netns_install(struct nsproxy *nsproxy, struct ns_common *ns)
1033 struct net *net = to_net_ns(ns);
1035 if (!ns_capable(net->user_ns, CAP_SYS_ADMIN) ||
1036 !ns_capable(current_user_ns(), CAP_SYS_ADMIN))
1039 put_net(nsproxy->net_ns);
1040 nsproxy->net_ns = get_net(net);
1044 static struct user_namespace *netns_owner(struct ns_common *ns)
1046 return to_net_ns(ns)->user_ns;
1049 const struct proc_ns_operations netns_operations = {
1051 .type = CLONE_NEWNET,
1054 .install = netns_install,
1055 .owner = netns_owner,