1 // SPDX-License-Identifier: GPL-2.0-only
2 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
4 #include <linux/workqueue.h>
5 #include <linux/rtnetlink.h>
6 #include <linux/cache.h>
7 #include <linux/slab.h>
8 #include <linux/list.h>
9 #include <linux/delay.h>
10 #include <linux/sched.h>
11 #include <linux/idr.h>
12 #include <linux/rculist.h>
13 #include <linux/nsproxy.h>
15 #include <linux/proc_ns.h>
16 #include <linux/file.h>
17 #include <linux/export.h>
18 #include <linux/user_namespace.h>
19 #include <linux/net_namespace.h>
20 #include <linux/sched/task.h>
21 #include <linux/uidgid.h>
24 #include <net/netlink.h>
25 #include <net/net_namespace.h>
26 #include <net/netns/generic.h>
29 * Our network namespace constructor/destructor lists
32 static LIST_HEAD(pernet_list
);
33 static struct list_head
*first_device
= &pernet_list
;
35 LIST_HEAD(net_namespace_list
);
36 EXPORT_SYMBOL_GPL(net_namespace_list
);
38 /* Protects net_namespace_list. Nests iside rtnl_lock() */
39 DECLARE_RWSEM(net_rwsem
);
40 EXPORT_SYMBOL_GPL(net_rwsem
);
43 static struct key_tag init_net_key_domain
= { .usage
= REFCOUNT_INIT(1) };
46 struct net init_net
= {
47 .count
= REFCOUNT_INIT(1),
48 .dev_base_head
= LIST_HEAD_INIT(init_net
.dev_base_head
),
50 .key_domain
= &init_net_key_domain
,
53 EXPORT_SYMBOL(init_net
);
55 static bool init_net_initialized
;
57 * pernet_ops_rwsem: protects: pernet_list, net_generic_ids,
58 * init_net_initialized and first_device pointer.
59 * This is internal net namespace object. Please, don't use it
62 DECLARE_RWSEM(pernet_ops_rwsem
);
63 EXPORT_SYMBOL_GPL(pernet_ops_rwsem
);
65 #define MIN_PERNET_OPS_ID \
66 ((sizeof(struct net_generic) + sizeof(void *) - 1) / sizeof(void *))
68 #define INITIAL_NET_GEN_PTRS 13 /* +1 for len +2 for rcu_head */
70 static unsigned int max_gen_ptrs
= INITIAL_NET_GEN_PTRS
;
72 static struct net_generic
*net_alloc_generic(void)
74 struct net_generic
*ng
;
75 unsigned int generic_size
= offsetof(struct net_generic
, ptr
[max_gen_ptrs
]);
77 ng
= kzalloc(generic_size
, GFP_KERNEL
);
79 ng
->s
.len
= max_gen_ptrs
;
84 static int net_assign_generic(struct net
*net
, unsigned int id
, void *data
)
86 struct net_generic
*ng
, *old_ng
;
88 BUG_ON(id
< MIN_PERNET_OPS_ID
);
90 old_ng
= rcu_dereference_protected(net
->gen
,
91 lockdep_is_held(&pernet_ops_rwsem
));
92 if (old_ng
->s
.len
> id
) {
93 old_ng
->ptr
[id
] = data
;
97 ng
= net_alloc_generic();
102 * Some synchronisation notes:
104 * The net_generic explores the net->gen array inside rcu
105 * read section. Besides once set the net->gen->ptr[x]
106 * pointer never changes (see rules in netns/generic.h).
108 * That said, we simply duplicate this array and schedule
109 * the old copy for kfree after a grace period.
112 memcpy(&ng
->ptr
[MIN_PERNET_OPS_ID
], &old_ng
->ptr
[MIN_PERNET_OPS_ID
],
113 (old_ng
->s
.len
- MIN_PERNET_OPS_ID
) * sizeof(void *));
116 rcu_assign_pointer(net
->gen
, ng
);
117 kfree_rcu(old_ng
, s
.rcu
);
121 static int ops_init(const struct pernet_operations
*ops
, struct net
*net
)
126 if (ops
->id
&& ops
->size
) {
127 data
= kzalloc(ops
->size
, GFP_KERNEL
);
131 err
= net_assign_generic(net
, *ops
->id
, data
);
137 err
= ops
->init(net
);
148 static void ops_free(const struct pernet_operations
*ops
, struct net
*net
)
150 if (ops
->id
&& ops
->size
) {
151 kfree(net_generic(net
, *ops
->id
));
155 static void ops_pre_exit_list(const struct pernet_operations
*ops
,
156 struct list_head
*net_exit_list
)
161 list_for_each_entry(net
, net_exit_list
, exit_list
)
166 static void ops_exit_list(const struct pernet_operations
*ops
,
167 struct list_head
*net_exit_list
)
171 list_for_each_entry(net
, net_exit_list
, exit_list
)
175 ops
->exit_batch(net_exit_list
);
178 static void ops_free_list(const struct pernet_operations
*ops
,
179 struct list_head
*net_exit_list
)
182 if (ops
->size
&& ops
->id
) {
183 list_for_each_entry(net
, net_exit_list
, exit_list
)
188 /* should be called with nsid_lock held */
189 static int alloc_netid(struct net
*net
, struct net
*peer
, int reqid
)
191 int min
= 0, max
= 0;
198 return idr_alloc(&net
->netns_ids
, peer
, min
, max
, GFP_ATOMIC
);
201 /* This function is used by idr_for_each(). If net is equal to peer, the
202 * function returns the id so that idr_for_each() stops. Because we cannot
203 * returns the id 0 (idr_for_each() will not stop), we return the magic value
204 * NET_ID_ZERO (-1) for it.
206 #define NET_ID_ZERO -1
207 static int net_eq_idr(int id
, void *net
, void *peer
)
209 if (net_eq(net
, peer
))
210 return id
? : NET_ID_ZERO
;
214 /* Should be called with nsid_lock held. If a new id is assigned, the bool alloc
215 * is set to true, thus the caller knows that the new id must be notified via
218 static int __peernet2id_alloc(struct net
*net
, struct net
*peer
, bool *alloc
)
220 int id
= idr_for_each(&net
->netns_ids
, net_eq_idr
, peer
);
221 bool alloc_it
= *alloc
;
225 /* Magic value for id 0. */
226 if (id
== NET_ID_ZERO
)
232 id
= alloc_netid(net
, peer
, -1);
234 return id
>= 0 ? id
: NETNSA_NSID_NOT_ASSIGNED
;
237 return NETNSA_NSID_NOT_ASSIGNED
;
240 /* should be called with nsid_lock held */
241 static int __peernet2id(struct net
*net
, struct net
*peer
)
245 return __peernet2id_alloc(net
, peer
, &no
);
248 static void rtnl_net_notifyid(struct net
*net
, int cmd
, int id
);
249 /* This function returns the id of a peer netns. If no id is assigned, one will
250 * be allocated and returned.
252 int peernet2id_alloc(struct net
*net
, struct net
*peer
)
254 bool alloc
= false, alive
= false;
257 if (refcount_read(&net
->count
) == 0)
258 return NETNSA_NSID_NOT_ASSIGNED
;
259 spin_lock_bh(&net
->nsid_lock
);
261 * When peer is obtained from RCU lists, we may race with
262 * its cleanup. Check whether it's alive, and this guarantees
263 * we never hash a peer back to net->netns_ids, after it has
264 * just been idr_remove()'d from there in cleanup_net().
266 if (maybe_get_net(peer
))
267 alive
= alloc
= true;
268 id
= __peernet2id_alloc(net
, peer
, &alloc
);
269 spin_unlock_bh(&net
->nsid_lock
);
270 if (alloc
&& id
>= 0)
271 rtnl_net_notifyid(net
, RTM_NEWNSID
, id
);
276 EXPORT_SYMBOL_GPL(peernet2id_alloc
);
278 /* This function returns, if assigned, the id of a peer netns. */
279 int peernet2id(struct net
*net
, struct net
*peer
)
283 spin_lock_bh(&net
->nsid_lock
);
284 id
= __peernet2id(net
, peer
);
285 spin_unlock_bh(&net
->nsid_lock
);
288 EXPORT_SYMBOL(peernet2id
);
290 /* This function returns true is the peer netns has an id assigned into the
293 bool peernet_has_id(struct net
*net
, struct net
*peer
)
295 return peernet2id(net
, peer
) >= 0;
298 struct net
*get_net_ns_by_id(struct net
*net
, int id
)
306 peer
= idr_find(&net
->netns_ids
, id
);
308 peer
= maybe_get_net(peer
);
315 * setup_net runs the initializers for the network namespace object.
317 static __net_init
int setup_net(struct net
*net
, struct user_namespace
*user_ns
)
319 /* Must be called with pernet_ops_rwsem held */
320 const struct pernet_operations
*ops
, *saved_ops
;
322 LIST_HEAD(net_exit_list
);
324 refcount_set(&net
->count
, 1);
325 refcount_set(&net
->passive
, 1);
326 get_random_bytes(&net
->hash_mix
, sizeof(u32
));
327 net
->dev_base_seq
= 1;
328 net
->user_ns
= user_ns
;
329 idr_init(&net
->netns_ids
);
330 spin_lock_init(&net
->nsid_lock
);
331 mutex_init(&net
->ipv4
.ra_mutex
);
333 list_for_each_entry(ops
, &pernet_list
, list
) {
334 error
= ops_init(ops
, net
);
338 down_write(&net_rwsem
);
339 list_add_tail_rcu(&net
->list
, &net_namespace_list
);
340 up_write(&net_rwsem
);
345 /* Walk through the list backwards calling the exit functions
346 * for the pernet modules whose init functions did not fail.
348 list_add(&net
->exit_list
, &net_exit_list
);
350 list_for_each_entry_continue_reverse(ops
, &pernet_list
, list
)
351 ops_pre_exit_list(ops
, &net_exit_list
);
356 list_for_each_entry_continue_reverse(ops
, &pernet_list
, list
)
357 ops_exit_list(ops
, &net_exit_list
);
360 list_for_each_entry_continue_reverse(ops
, &pernet_list
, list
)
361 ops_free_list(ops
, &net_exit_list
);
367 static int __net_init
net_defaults_init_net(struct net
*net
)
369 net
->core
.sysctl_somaxconn
= SOMAXCONN
;
373 static struct pernet_operations net_defaults_ops
= {
374 .init
= net_defaults_init_net
,
377 static __init
int net_defaults_init(void)
379 if (register_pernet_subsys(&net_defaults_ops
))
380 panic("Cannot initialize net default settings");
385 core_initcall(net_defaults_init
);
388 static struct ucounts
*inc_net_namespaces(struct user_namespace
*ns
)
390 return inc_ucount(ns
, current_euid(), UCOUNT_NET_NAMESPACES
);
393 static void dec_net_namespaces(struct ucounts
*ucounts
)
395 dec_ucount(ucounts
, UCOUNT_NET_NAMESPACES
);
398 static struct kmem_cache
*net_cachep __ro_after_init
;
399 static struct workqueue_struct
*netns_wq
;
401 static struct net
*net_alloc(void)
403 struct net
*net
= NULL
;
404 struct net_generic
*ng
;
406 ng
= net_alloc_generic();
410 net
= kmem_cache_zalloc(net_cachep
, GFP_KERNEL
);
415 net
->key_domain
= kzalloc(sizeof(struct key_tag
), GFP_KERNEL
);
416 if (!net
->key_domain
)
418 refcount_set(&net
->key_domain
->usage
, 1);
421 rcu_assign_pointer(net
->gen
, ng
);
427 kmem_cache_free(net_cachep
, net
);
435 static void net_free(struct net
*net
)
437 kfree(rcu_access_pointer(net
->gen
));
438 kmem_cache_free(net_cachep
, net
);
441 void net_drop_ns(void *p
)
444 if (ns
&& refcount_dec_and_test(&ns
->passive
))
448 struct net
*copy_net_ns(unsigned long flags
,
449 struct user_namespace
*user_ns
, struct net
*old_net
)
451 struct ucounts
*ucounts
;
455 if (!(flags
& CLONE_NEWNET
))
456 return get_net(old_net
);
458 ucounts
= inc_net_namespaces(user_ns
);
460 return ERR_PTR(-ENOSPC
);
467 refcount_set(&net
->passive
, 1);
468 net
->ucounts
= ucounts
;
469 get_user_ns(user_ns
);
471 rv
= down_read_killable(&pernet_ops_rwsem
);
475 rv
= setup_net(net
, user_ns
);
477 up_read(&pernet_ops_rwsem
);
481 put_user_ns(user_ns
);
484 dec_net_namespaces(ucounts
);
491 * net_ns_get_ownership - get sysfs ownership data for @net
492 * @net: network namespace in question (can be NULL)
493 * @uid: kernel user ID for sysfs objects
494 * @gid: kernel group ID for sysfs objects
496 * Returns the uid/gid pair of root in the user namespace associated with the
497 * given network namespace.
499 void net_ns_get_ownership(const struct net
*net
, kuid_t
*uid
, kgid_t
*gid
)
502 kuid_t ns_root_uid
= make_kuid(net
->user_ns
, 0);
503 kgid_t ns_root_gid
= make_kgid(net
->user_ns
, 0);
505 if (uid_valid(ns_root_uid
))
508 if (gid_valid(ns_root_gid
))
511 *uid
= GLOBAL_ROOT_UID
;
512 *gid
= GLOBAL_ROOT_GID
;
515 EXPORT_SYMBOL_GPL(net_ns_get_ownership
);
517 static void unhash_nsid(struct net
*net
, struct net
*last
)
520 /* This function is only called from cleanup_net() work,
521 * and this work is the only process, that may delete
522 * a net from net_namespace_list. So, when the below
523 * is executing, the list may only grow. Thus, we do not
524 * use for_each_net_rcu() or net_rwsem.
529 spin_lock_bh(&tmp
->nsid_lock
);
530 id
= __peernet2id(tmp
, net
);
532 idr_remove(&tmp
->netns_ids
, id
);
533 spin_unlock_bh(&tmp
->nsid_lock
);
535 rtnl_net_notifyid(tmp
, RTM_DELNSID
, id
);
539 spin_lock_bh(&net
->nsid_lock
);
540 idr_destroy(&net
->netns_ids
);
541 spin_unlock_bh(&net
->nsid_lock
);
544 static LLIST_HEAD(cleanup_list
);
546 static void cleanup_net(struct work_struct
*work
)
548 const struct pernet_operations
*ops
;
549 struct net
*net
, *tmp
, *last
;
550 struct llist_node
*net_kill_list
;
551 LIST_HEAD(net_exit_list
);
553 /* Atomically snapshot the list of namespaces to cleanup */
554 net_kill_list
= llist_del_all(&cleanup_list
);
556 down_read(&pernet_ops_rwsem
);
558 /* Don't let anyone else find us. */
559 down_write(&net_rwsem
);
560 llist_for_each_entry(net
, net_kill_list
, cleanup_list
)
561 list_del_rcu(&net
->list
);
562 /* Cache last net. After we unlock rtnl, no one new net
563 * added to net_namespace_list can assign nsid pointer
564 * to a net from net_kill_list (see peernet2id_alloc()).
565 * So, we skip them in unhash_nsid().
567 * Note, that unhash_nsid() does not delete nsid links
568 * between net_kill_list's nets, as they've already
569 * deleted from net_namespace_list. But, this would be
570 * useless anyway, as netns_ids are destroyed there.
572 last
= list_last_entry(&net_namespace_list
, struct net
, list
);
573 up_write(&net_rwsem
);
575 llist_for_each_entry(net
, net_kill_list
, cleanup_list
) {
576 unhash_nsid(net
, last
);
577 list_add_tail(&net
->exit_list
, &net_exit_list
);
580 /* Run all of the network namespace pre_exit methods */
581 list_for_each_entry_reverse(ops
, &pernet_list
, list
)
582 ops_pre_exit_list(ops
, &net_exit_list
);
585 * Another CPU might be rcu-iterating the list, wait for it.
586 * This needs to be before calling the exit() notifiers, so
587 * the rcu_barrier() below isn't sufficient alone.
588 * Also the pre_exit() and exit() methods need this barrier.
592 /* Run all of the network namespace exit methods */
593 list_for_each_entry_reverse(ops
, &pernet_list
, list
)
594 ops_exit_list(ops
, &net_exit_list
);
596 /* Free the net generic variables */
597 list_for_each_entry_reverse(ops
, &pernet_list
, list
)
598 ops_free_list(ops
, &net_exit_list
);
600 up_read(&pernet_ops_rwsem
);
602 /* Ensure there are no outstanding rcu callbacks using this
607 /* Finally it is safe to free my network namespace structure */
608 list_for_each_entry_safe(net
, tmp
, &net_exit_list
, exit_list
) {
609 list_del_init(&net
->exit_list
);
610 dec_net_namespaces(net
->ucounts
);
611 key_remove_domain(net
->key_domain
);
612 put_user_ns(net
->user_ns
);
618 * net_ns_barrier - wait until concurrent net_cleanup_work is done
620 * cleanup_net runs from work queue and will first remove namespaces
621 * from the global list, then run net exit functions.
623 * Call this in module exit path to make sure that all netns
624 * ->exit ops have been invoked before the function is removed.
626 void net_ns_barrier(void)
628 down_write(&pernet_ops_rwsem
);
629 up_write(&pernet_ops_rwsem
);
631 EXPORT_SYMBOL(net_ns_barrier
);
633 static DECLARE_WORK(net_cleanup_work
, cleanup_net
);
635 void __put_net(struct net
*net
)
637 /* Cleanup the network namespace in process context */
638 if (llist_add(&net
->cleanup_list
, &cleanup_list
))
639 queue_work(netns_wq
, &net_cleanup_work
);
641 EXPORT_SYMBOL_GPL(__put_net
);
643 struct net
*get_net_ns_by_fd(int fd
)
646 struct ns_common
*ns
;
649 file
= proc_ns_fget(fd
);
651 return ERR_CAST(file
);
653 ns
= get_proc_ns(file_inode(file
));
654 if (ns
->ops
== &netns_operations
)
655 net
= get_net(container_of(ns
, struct net
, ns
));
657 net
= ERR_PTR(-EINVAL
);
664 struct net
*get_net_ns_by_fd(int fd
)
666 return ERR_PTR(-EINVAL
);
669 EXPORT_SYMBOL_GPL(get_net_ns_by_fd
);
671 struct net
*get_net_ns_by_pid(pid_t pid
)
673 struct task_struct
*tsk
;
676 /* Lookup the network namespace */
677 net
= ERR_PTR(-ESRCH
);
679 tsk
= find_task_by_vpid(pid
);
681 struct nsproxy
*nsproxy
;
683 nsproxy
= tsk
->nsproxy
;
685 net
= get_net(nsproxy
->net_ns
);
691 EXPORT_SYMBOL_GPL(get_net_ns_by_pid
);
693 static __net_init
int net_ns_net_init(struct net
*net
)
696 net
->ns
.ops
= &netns_operations
;
698 return ns_alloc_inum(&net
->ns
);
701 static __net_exit
void net_ns_net_exit(struct net
*net
)
703 ns_free_inum(&net
->ns
);
706 static struct pernet_operations __net_initdata net_ns_ops
= {
707 .init
= net_ns_net_init
,
708 .exit
= net_ns_net_exit
,
711 static const struct nla_policy rtnl_net_policy
[NETNSA_MAX
+ 1] = {
712 [NETNSA_NONE
] = { .type
= NLA_UNSPEC
},
713 [NETNSA_NSID
] = { .type
= NLA_S32
},
714 [NETNSA_PID
] = { .type
= NLA_U32
},
715 [NETNSA_FD
] = { .type
= NLA_U32
},
716 [NETNSA_TARGET_NSID
] = { .type
= NLA_S32
},
719 static int rtnl_net_newid(struct sk_buff
*skb
, struct nlmsghdr
*nlh
,
720 struct netlink_ext_ack
*extack
)
722 struct net
*net
= sock_net(skb
->sk
);
723 struct nlattr
*tb
[NETNSA_MAX
+ 1];
728 err
= nlmsg_parse_deprecated(nlh
, sizeof(struct rtgenmsg
), tb
,
729 NETNSA_MAX
, rtnl_net_policy
, extack
);
732 if (!tb
[NETNSA_NSID
]) {
733 NL_SET_ERR_MSG(extack
, "nsid is missing");
736 nsid
= nla_get_s32(tb
[NETNSA_NSID
]);
738 if (tb
[NETNSA_PID
]) {
739 peer
= get_net_ns_by_pid(nla_get_u32(tb
[NETNSA_PID
]));
740 nla
= tb
[NETNSA_PID
];
741 } else if (tb
[NETNSA_FD
]) {
742 peer
= get_net_ns_by_fd(nla_get_u32(tb
[NETNSA_FD
]));
745 NL_SET_ERR_MSG(extack
, "Peer netns reference is missing");
749 NL_SET_BAD_ATTR(extack
, nla
);
750 NL_SET_ERR_MSG(extack
, "Peer netns reference is invalid");
751 return PTR_ERR(peer
);
754 spin_lock_bh(&net
->nsid_lock
);
755 if (__peernet2id(net
, peer
) >= 0) {
756 spin_unlock_bh(&net
->nsid_lock
);
758 NL_SET_BAD_ATTR(extack
, nla
);
759 NL_SET_ERR_MSG(extack
,
760 "Peer netns already has a nsid assigned");
764 err
= alloc_netid(net
, peer
, nsid
);
765 spin_unlock_bh(&net
->nsid_lock
);
767 rtnl_net_notifyid(net
, RTM_NEWNSID
, err
);
769 } else if (err
== -ENOSPC
&& nsid
>= 0) {
771 NL_SET_BAD_ATTR(extack
, tb
[NETNSA_NSID
]);
772 NL_SET_ERR_MSG(extack
, "The specified nsid is already used");
779 static int rtnl_net_get_size(void)
781 return NLMSG_ALIGN(sizeof(struct rtgenmsg
))
782 + nla_total_size(sizeof(s32
)) /* NETNSA_NSID */
783 + nla_total_size(sizeof(s32
)) /* NETNSA_CURRENT_NSID */
787 struct net_fill_args
{
797 static int rtnl_net_fill(struct sk_buff
*skb
, struct net_fill_args
*args
)
799 struct nlmsghdr
*nlh
;
800 struct rtgenmsg
*rth
;
802 nlh
= nlmsg_put(skb
, args
->portid
, args
->seq
, args
->cmd
, sizeof(*rth
),
807 rth
= nlmsg_data(nlh
);
808 rth
->rtgen_family
= AF_UNSPEC
;
810 if (nla_put_s32(skb
, NETNSA_NSID
, args
->nsid
))
811 goto nla_put_failure
;
814 nla_put_s32(skb
, NETNSA_CURRENT_NSID
, args
->ref_nsid
))
815 goto nla_put_failure
;
821 nlmsg_cancel(skb
, nlh
);
825 static int rtnl_net_valid_getid_req(struct sk_buff
*skb
,
826 const struct nlmsghdr
*nlh
,
828 struct netlink_ext_ack
*extack
)
832 if (!netlink_strict_get_check(skb
))
833 return nlmsg_parse_deprecated(nlh
, sizeof(struct rtgenmsg
),
834 tb
, NETNSA_MAX
, rtnl_net_policy
,
837 err
= nlmsg_parse_deprecated_strict(nlh
, sizeof(struct rtgenmsg
), tb
,
838 NETNSA_MAX
, rtnl_net_policy
,
843 for (i
= 0; i
<= NETNSA_MAX
; i
++) {
851 case NETNSA_TARGET_NSID
:
854 NL_SET_ERR_MSG(extack
, "Unsupported attribute in peer netns getid request");
862 static int rtnl_net_getid(struct sk_buff
*skb
, struct nlmsghdr
*nlh
,
863 struct netlink_ext_ack
*extack
)
865 struct net
*net
= sock_net(skb
->sk
);
866 struct nlattr
*tb
[NETNSA_MAX
+ 1];
867 struct net_fill_args fillargs
= {
868 .portid
= NETLINK_CB(skb
).portid
,
869 .seq
= nlh
->nlmsg_seq
,
872 struct net
*peer
, *target
= net
;
877 err
= rtnl_net_valid_getid_req(skb
, nlh
, tb
, extack
);
880 if (tb
[NETNSA_PID
]) {
881 peer
= get_net_ns_by_pid(nla_get_u32(tb
[NETNSA_PID
]));
882 nla
= tb
[NETNSA_PID
];
883 } else if (tb
[NETNSA_FD
]) {
884 peer
= get_net_ns_by_fd(nla_get_u32(tb
[NETNSA_FD
]));
886 } else if (tb
[NETNSA_NSID
]) {
887 peer
= get_net_ns_by_id(net
, nla_get_s32(tb
[NETNSA_NSID
]));
889 peer
= ERR_PTR(-ENOENT
);
890 nla
= tb
[NETNSA_NSID
];
892 NL_SET_ERR_MSG(extack
, "Peer netns reference is missing");
897 NL_SET_BAD_ATTR(extack
, nla
);
898 NL_SET_ERR_MSG(extack
, "Peer netns reference is invalid");
899 return PTR_ERR(peer
);
902 if (tb
[NETNSA_TARGET_NSID
]) {
903 int id
= nla_get_s32(tb
[NETNSA_TARGET_NSID
]);
905 target
= rtnl_get_net_ns_capable(NETLINK_CB(skb
).sk
, id
);
906 if (IS_ERR(target
)) {
907 NL_SET_BAD_ATTR(extack
, tb
[NETNSA_TARGET_NSID
]);
908 NL_SET_ERR_MSG(extack
,
909 "Target netns reference is invalid");
910 err
= PTR_ERR(target
);
913 fillargs
.add_ref
= true;
914 fillargs
.ref_nsid
= peernet2id(net
, peer
);
917 msg
= nlmsg_new(rtnl_net_get_size(), GFP_KERNEL
);
923 fillargs
.nsid
= peernet2id(target
, peer
);
924 err
= rtnl_net_fill(msg
, &fillargs
);
928 err
= rtnl_unicast(msg
, net
, NETLINK_CB(skb
).portid
);
934 if (fillargs
.add_ref
)
940 struct rtnl_net_dump_cb
{
944 struct net_fill_args fillargs
;
949 static int rtnl_net_dumpid_one(int id
, void *peer
, void *data
)
951 struct rtnl_net_dump_cb
*net_cb
= (struct rtnl_net_dump_cb
*)data
;
954 if (net_cb
->idx
< net_cb
->s_idx
)
957 net_cb
->fillargs
.nsid
= id
;
958 if (net_cb
->fillargs
.add_ref
)
959 net_cb
->fillargs
.ref_nsid
= __peernet2id(net_cb
->ref_net
, peer
);
960 ret
= rtnl_net_fill(net_cb
->skb
, &net_cb
->fillargs
);
969 static int rtnl_valid_dump_net_req(const struct nlmsghdr
*nlh
, struct sock
*sk
,
970 struct rtnl_net_dump_cb
*net_cb
,
971 struct netlink_callback
*cb
)
973 struct netlink_ext_ack
*extack
= cb
->extack
;
974 struct nlattr
*tb
[NETNSA_MAX
+ 1];
977 err
= nlmsg_parse_deprecated_strict(nlh
, sizeof(struct rtgenmsg
), tb
,
978 NETNSA_MAX
, rtnl_net_policy
,
983 for (i
= 0; i
<= NETNSA_MAX
; i
++) {
987 if (i
== NETNSA_TARGET_NSID
) {
990 net
= rtnl_get_net_ns_capable(sk
, nla_get_s32(tb
[i
]));
992 NL_SET_BAD_ATTR(extack
, tb
[i
]);
993 NL_SET_ERR_MSG(extack
,
994 "Invalid target network namespace id");
997 net_cb
->fillargs
.add_ref
= true;
998 net_cb
->ref_net
= net_cb
->tgt_net
;
999 net_cb
->tgt_net
= net
;
1001 NL_SET_BAD_ATTR(extack
, tb
[i
]);
1002 NL_SET_ERR_MSG(extack
,
1003 "Unsupported attribute in dump request");
1011 static int rtnl_net_dumpid(struct sk_buff
*skb
, struct netlink_callback
*cb
)
1013 struct rtnl_net_dump_cb net_cb
= {
1014 .tgt_net
= sock_net(skb
->sk
),
1017 .portid
= NETLINK_CB(cb
->skb
).portid
,
1018 .seq
= cb
->nlh
->nlmsg_seq
,
1019 .flags
= NLM_F_MULTI
,
1023 .s_idx
= cb
->args
[0],
1027 if (cb
->strict_check
) {
1028 err
= rtnl_valid_dump_net_req(cb
->nlh
, skb
->sk
, &net_cb
, cb
);
1033 spin_lock_bh(&net_cb
.tgt_net
->nsid_lock
);
1034 if (net_cb
.fillargs
.add_ref
&&
1035 !net_eq(net_cb
.ref_net
, net_cb
.tgt_net
) &&
1036 !spin_trylock_bh(&net_cb
.ref_net
->nsid_lock
)) {
1037 spin_unlock_bh(&net_cb
.tgt_net
->nsid_lock
);
1041 idr_for_each(&net_cb
.tgt_net
->netns_ids
, rtnl_net_dumpid_one
, &net_cb
);
1042 if (net_cb
.fillargs
.add_ref
&&
1043 !net_eq(net_cb
.ref_net
, net_cb
.tgt_net
))
1044 spin_unlock_bh(&net_cb
.ref_net
->nsid_lock
);
1045 spin_unlock_bh(&net_cb
.tgt_net
->nsid_lock
);
1047 cb
->args
[0] = net_cb
.idx
;
1049 if (net_cb
.fillargs
.add_ref
)
1050 put_net(net_cb
.tgt_net
);
1051 return err
< 0 ? err
: skb
->len
;
1054 static void rtnl_net_notifyid(struct net
*net
, int cmd
, int id
)
1056 struct net_fill_args fillargs
= {
1060 struct sk_buff
*msg
;
1063 msg
= nlmsg_new(rtnl_net_get_size(), GFP_KERNEL
);
1067 err
= rtnl_net_fill(msg
, &fillargs
);
1071 rtnl_notify(msg
, net
, 0, RTNLGRP_NSID
, NULL
, 0);
1077 rtnl_set_sk_err(net
, RTNLGRP_NSID
, err
);
1080 static int __init
net_ns_init(void)
1082 struct net_generic
*ng
;
1084 #ifdef CONFIG_NET_NS
1085 net_cachep
= kmem_cache_create("net_namespace", sizeof(struct net
),
1087 SLAB_PANIC
|SLAB_ACCOUNT
, NULL
);
1089 /* Create workqueue for cleanup */
1090 netns_wq
= create_singlethread_workqueue("netns");
1092 panic("Could not create netns workq");
1095 ng
= net_alloc_generic();
1097 panic("Could not allocate generic netns");
1099 rcu_assign_pointer(init_net
.gen
, ng
);
1101 down_write(&pernet_ops_rwsem
);
1102 if (setup_net(&init_net
, &init_user_ns
))
1103 panic("Could not setup the initial network namespace");
1105 init_net_initialized
= true;
1106 up_write(&pernet_ops_rwsem
);
1108 if (register_pernet_subsys(&net_ns_ops
))
1109 panic("Could not register network namespace subsystems");
1111 rtnl_register(PF_UNSPEC
, RTM_NEWNSID
, rtnl_net_newid
, NULL
,
1112 RTNL_FLAG_DOIT_UNLOCKED
);
1113 rtnl_register(PF_UNSPEC
, RTM_GETNSID
, rtnl_net_getid
, rtnl_net_dumpid
,
1114 RTNL_FLAG_DOIT_UNLOCKED
);
1119 pure_initcall(net_ns_init
);
1121 #ifdef CONFIG_NET_NS
1122 static int __register_pernet_operations(struct list_head
*list
,
1123 struct pernet_operations
*ops
)
1127 LIST_HEAD(net_exit_list
);
1129 list_add_tail(&ops
->list
, list
);
1130 if (ops
->init
|| (ops
->id
&& ops
->size
)) {
1131 /* We held write locked pernet_ops_rwsem, and parallel
1132 * setup_net() and cleanup_net() are not possible.
1135 error
= ops_init(ops
, net
);
1138 list_add_tail(&net
->exit_list
, &net_exit_list
);
1144 /* If I have an error cleanup all namespaces I initialized */
1145 list_del(&ops
->list
);
1146 ops_pre_exit_list(ops
, &net_exit_list
);
1148 ops_exit_list(ops
, &net_exit_list
);
1149 ops_free_list(ops
, &net_exit_list
);
1153 static void __unregister_pernet_operations(struct pernet_operations
*ops
)
1156 LIST_HEAD(net_exit_list
);
1158 list_del(&ops
->list
);
1159 /* See comment in __register_pernet_operations() */
1161 list_add_tail(&net
->exit_list
, &net_exit_list
);
1162 ops_pre_exit_list(ops
, &net_exit_list
);
1164 ops_exit_list(ops
, &net_exit_list
);
1165 ops_free_list(ops
, &net_exit_list
);
1170 static int __register_pernet_operations(struct list_head
*list
,
1171 struct pernet_operations
*ops
)
1173 if (!init_net_initialized
) {
1174 list_add_tail(&ops
->list
, list
);
1178 return ops_init(ops
, &init_net
);
1181 static void __unregister_pernet_operations(struct pernet_operations
*ops
)
1183 if (!init_net_initialized
) {
1184 list_del(&ops
->list
);
1186 LIST_HEAD(net_exit_list
);
1187 list_add(&init_net
.exit_list
, &net_exit_list
);
1188 ops_pre_exit_list(ops
, &net_exit_list
);
1190 ops_exit_list(ops
, &net_exit_list
);
1191 ops_free_list(ops
, &net_exit_list
);
1195 #endif /* CONFIG_NET_NS */
1197 static DEFINE_IDA(net_generic_ids
);
1199 static int register_pernet_operations(struct list_head
*list
,
1200 struct pernet_operations
*ops
)
1205 error
= ida_alloc_min(&net_generic_ids
, MIN_PERNET_OPS_ID
,
1210 max_gen_ptrs
= max(max_gen_ptrs
, *ops
->id
+ 1);
1212 error
= __register_pernet_operations(list
, ops
);
1216 ida_free(&net_generic_ids
, *ops
->id
);
1222 static void unregister_pernet_operations(struct pernet_operations
*ops
)
1224 __unregister_pernet_operations(ops
);
1227 ida_free(&net_generic_ids
, *ops
->id
);
1231 * register_pernet_subsys - register a network namespace subsystem
1232 * @ops: pernet operations structure for the subsystem
1234 * Register a subsystem which has init and exit functions
1235 * that are called when network namespaces are created and
1236 * destroyed respectively.
1238 * When registered all network namespace init functions are
1239 * called for every existing network namespace. Allowing kernel
1240 * modules to have a race free view of the set of network namespaces.
1242 * When a new network namespace is created all of the init
1243 * methods are called in the order in which they were registered.
1245 * When a network namespace is destroyed all of the exit methods
1246 * are called in the reverse of the order with which they were
1249 int register_pernet_subsys(struct pernet_operations
*ops
)
1252 down_write(&pernet_ops_rwsem
);
1253 error
= register_pernet_operations(first_device
, ops
);
1254 up_write(&pernet_ops_rwsem
);
1257 EXPORT_SYMBOL_GPL(register_pernet_subsys
);
1260 * unregister_pernet_subsys - unregister a network namespace subsystem
1261 * @ops: pernet operations structure to manipulate
1263 * Remove the pernet operations structure from the list to be
1264 * used when network namespaces are created or destroyed. In
1265 * addition run the exit method for all existing network
1268 void unregister_pernet_subsys(struct pernet_operations
*ops
)
1270 down_write(&pernet_ops_rwsem
);
1271 unregister_pernet_operations(ops
);
1272 up_write(&pernet_ops_rwsem
);
1274 EXPORT_SYMBOL_GPL(unregister_pernet_subsys
);
1277 * register_pernet_device - register a network namespace device
1278 * @ops: pernet operations structure for the subsystem
1280 * Register a device which has init and exit functions
1281 * that are called when network namespaces are created and
1282 * destroyed respectively.
1284 * When registered all network namespace init functions are
1285 * called for every existing network namespace. Allowing kernel
1286 * modules to have a race free view of the set of network namespaces.
1288 * When a new network namespace is created all of the init
1289 * methods are called in the order in which they were registered.
1291 * When a network namespace is destroyed all of the exit methods
1292 * are called in the reverse of the order with which they were
1295 int register_pernet_device(struct pernet_operations
*ops
)
1298 down_write(&pernet_ops_rwsem
);
1299 error
= register_pernet_operations(&pernet_list
, ops
);
1300 if (!error
&& (first_device
== &pernet_list
))
1301 first_device
= &ops
->list
;
1302 up_write(&pernet_ops_rwsem
);
1305 EXPORT_SYMBOL_GPL(register_pernet_device
);
1308 * unregister_pernet_device - unregister a network namespace netdevice
1309 * @ops: pernet operations structure to manipulate
1311 * Remove the pernet operations structure from the list to be
1312 * used when network namespaces are created or destroyed. In
1313 * addition run the exit method for all existing network
1316 void unregister_pernet_device(struct pernet_operations
*ops
)
1318 down_write(&pernet_ops_rwsem
);
1319 if (&ops
->list
== first_device
)
1320 first_device
= first_device
->next
;
1321 unregister_pernet_operations(ops
);
1322 up_write(&pernet_ops_rwsem
);
1324 EXPORT_SYMBOL_GPL(unregister_pernet_device
);
1326 #ifdef CONFIG_NET_NS
1327 static struct ns_common
*netns_get(struct task_struct
*task
)
1329 struct net
*net
= NULL
;
1330 struct nsproxy
*nsproxy
;
1333 nsproxy
= task
->nsproxy
;
1335 net
= get_net(nsproxy
->net_ns
);
1338 return net
? &net
->ns
: NULL
;
1341 static inline struct net
*to_net_ns(struct ns_common
*ns
)
1343 return container_of(ns
, struct net
, ns
);
1346 static void netns_put(struct ns_common
*ns
)
1348 put_net(to_net_ns(ns
));
1351 static int netns_install(struct nsproxy
*nsproxy
, struct ns_common
*ns
)
1353 struct net
*net
= to_net_ns(ns
);
1355 if (!ns_capable(net
->user_ns
, CAP_SYS_ADMIN
) ||
1356 !ns_capable(current_user_ns(), CAP_SYS_ADMIN
))
1359 put_net(nsproxy
->net_ns
);
1360 nsproxy
->net_ns
= get_net(net
);
1364 static struct user_namespace
*netns_owner(struct ns_common
*ns
)
1366 return to_net_ns(ns
)->user_ns
;
1369 const struct proc_ns_operations netns_operations
= {
1371 .type
= CLONE_NEWNET
,
1374 .install
= netns_install
,
1375 .owner
= netns_owner
,