1// SPDX-License-Identifier: GPL-2.0-only 2#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 3 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> 14#include <linux/fs.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> 22#include <linux/cookie.h> 23#include <linux/proc_fs.h> 24 25#include <net/sock.h> 26#include <net/netlink.h> 27#include <net/net_namespace.h> 28#include <net/netns/generic.h> 29 30/* 31 * Our network namespace constructor/destructor lists 32 */ 33 34static LIST_HEAD(pernet_list); 35static struct list_head *first_device = &pernet_list; 36 37LIST_HEAD(net_namespace_list); 38EXPORT_SYMBOL_GPL(net_namespace_list); 39 40/* Protects net_namespace_list. Nests iside rtnl_lock() */ 41DECLARE_RWSEM(net_rwsem); 42EXPORT_SYMBOL_GPL(net_rwsem); 43 44#ifdef CONFIG_KEYS 45static struct key_tag init_net_key_domain = { .usage = REFCOUNT_INIT(1) }; 46#endif 47 48struct net init_net; 49EXPORT_SYMBOL(init_net); 50 51static bool init_net_initialized; 52/* 53 * pernet_ops_rwsem: protects: pernet_list, net_generic_ids, 54 * init_net_initialized and first_device pointer. 55 * This is internal net namespace object. Please, don't use it 56 * outside. 57 */ 58DECLARE_RWSEM(pernet_ops_rwsem); 59EXPORT_SYMBOL_GPL(pernet_ops_rwsem); 60 61#define MIN_PERNET_OPS_ID \ 62 ((sizeof(struct net_generic) + sizeof(void *) - 1) / sizeof(void *)) 63 64#define INITIAL_NET_GEN_PTRS 13 /* +1 for len +2 for rcu_head */ 65 66static unsigned int max_gen_ptrs = INITIAL_NET_GEN_PTRS; 67 68DEFINE_COOKIE(net_cookie); 69 70static struct net_generic *net_alloc_generic(void) 71{ 72 struct net_generic *ng; 73 unsigned int generic_size = offsetof(struct net_generic, ptr[max_gen_ptrs]); 74 75 ng = kzalloc(generic_size, GFP_KERNEL); 76 if (ng) 77 ng->s.len = max_gen_ptrs; 78 79 return ng; 80} 81 82static int net_assign_generic(struct net *net, unsigned int id, void *data) 83{ 84 struct net_generic *ng, *old_ng; 85 86 BUG_ON(id < MIN_PERNET_OPS_ID); 87 88 old_ng = rcu_dereference_protected(net->gen, 89 lockdep_is_held(&pernet_ops_rwsem)); 90 if (old_ng->s.len > id) { 91 old_ng->ptr[id] = data; 92 return 0; 93 } 94 95 ng = net_alloc_generic(); 96 if (!ng) 97 return -ENOMEM; 98 99 /* 100 * Some synchronisation notes: 101 * 102 * The net_generic explores the net->gen array inside rcu 103 * read section. Besides once set the net->gen->ptr[x] 104 * pointer never changes (see rules in netns/generic.h). 105 * 106 * That said, we simply duplicate this array and schedule 107 * the old copy for kfree after a grace period. 108 */ 109 110 memcpy(&ng->ptr[MIN_PERNET_OPS_ID], &old_ng->ptr[MIN_PERNET_OPS_ID], 111 (old_ng->s.len - MIN_PERNET_OPS_ID) * sizeof(void *)); 112 ng->ptr[id] = data; 113 114 rcu_assign_pointer(net->gen, ng); 115 kfree_rcu(old_ng, s.rcu); 116 return 0; 117} 118 119static int ops_init(const struct pernet_operations *ops, struct net *net) 120{ 121 struct net_generic *ng; 122 int err = -ENOMEM; 123 void *data = NULL; 124 125 if (ops->id && ops->size) { 126 data = kzalloc(ops->size, GFP_KERNEL); 127 if (!data) 128 goto out; 129 130 err = net_assign_generic(net, *ops->id, data); 131 if (err) 132 goto cleanup; 133 } 134 err = 0; 135 if (ops->init) 136 err = ops->init(net); 137 if (!err) 138 return 0; 139 140 if (ops->id && ops->size) { 141 ng = rcu_dereference_protected(net->gen, 142 lockdep_is_held(&pernet_ops_rwsem)); 143 ng->ptr[*ops->id] = NULL; 144 } 145 146cleanup: 147 kfree(data); 148 149out: 150 return err; 151} 152 153static void ops_pre_exit_list(const struct pernet_operations *ops, 154 struct list_head *net_exit_list) 155{ 156 struct net *net; 157 158 if (ops->pre_exit) { 159 list_for_each_entry(net, net_exit_list, exit_list) 160 ops->pre_exit(net); 161 } 162} 163 164static void ops_exit_list(const struct pernet_operations *ops, 165 struct list_head *net_exit_list) 166{ 167 struct net *net; 168 if (ops->exit) { 169 list_for_each_entry(net, net_exit_list, exit_list) { 170 ops->exit(net); 171 cond_resched(); 172 } 173 } 174 if (ops->exit_batch) 175 ops->exit_batch(net_exit_list); 176} 177 178static void ops_free_list(const struct pernet_operations *ops, 179 struct list_head *net_exit_list) 180{ 181 struct net *net; 182 if (ops->size && ops->id) { 183 list_for_each_entry(net, net_exit_list, exit_list) 184 kfree(net_generic(net, *ops->id)); 185 } 186} 187 188/* should be called with nsid_lock held */ 189static int alloc_netid(struct net *net, struct net *peer, int reqid) 190{ 191 int min = 0, max = 0; 192 193 if (reqid >= 0) { 194 min = reqid; 195 max = reqid + 1; 196 } 197 198 return idr_alloc(&net->netns_ids, peer, min, max, GFP_ATOMIC); 199} 200 201/* 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. 205 */ 206#define NET_ID_ZERO -1 207static int net_eq_idr(int id, void *net, void *peer) 208{ 209 if (net_eq(net, peer)) 210 return id ? : NET_ID_ZERO; 211 return 0; 212} 213 214/* Must be called from RCU-critical section or with nsid_lock held */ 215static int __peernet2id(const struct net *net, struct net *peer) 216{ 217 int id = idr_for_each(&net->netns_ids, net_eq_idr, peer); 218 219 /* Magic value for id 0. */ 220 if (id == NET_ID_ZERO) 221 return 0; 222 if (id > 0) 223 return id; 224 225 return NETNSA_NSID_NOT_ASSIGNED; 226} 227 228static void rtnl_net_notifyid(struct net *net, int cmd, int id, u32 portid, 229 struct nlmsghdr *nlh, gfp_t gfp); 230/* This function returns the id of a peer netns. If no id is assigned, one will 231 * be allocated and returned. 232 */ 233int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp) 234{ 235 int id; 236 237 if (refcount_read(&net->ns.count) == 0) 238 return NETNSA_NSID_NOT_ASSIGNED; 239 240 spin_lock_bh(&net->nsid_lock); 241 id = __peernet2id(net, peer); 242 if (id >= 0) { 243 spin_unlock_bh(&net->nsid_lock); 244 return id; 245 } 246 247 /* When peer is obtained from RCU lists, we may race with 248 * its cleanup. Check whether it's alive, and this guarantees 249 * we never hash a peer back to net->netns_ids, after it has 250 * just been idr_remove()'d from there in cleanup_net(). 251 */ 252 if (!maybe_get_net(peer)) { 253 spin_unlock_bh(&net->nsid_lock); 254 return NETNSA_NSID_NOT_ASSIGNED; 255 } 256 257 id = alloc_netid(net, peer, -1); 258 spin_unlock_bh(&net->nsid_lock); 259 260 put_net(peer); 261 if (id < 0) 262 return NETNSA_NSID_NOT_ASSIGNED; 263 264 rtnl_net_notifyid(net, RTM_NEWNSID, id, 0, NULL, gfp); 265 266 return id; 267} 268EXPORT_SYMBOL_GPL(peernet2id_alloc); 269 270/* This function returns, if assigned, the id of a peer netns. */ 271int peernet2id(const struct net *net, struct net *peer) 272{ 273 int id; 274 275 rcu_read_lock(); 276 id = __peernet2id(net, peer); 277 rcu_read_unlock(); 278 279 return id; 280} 281EXPORT_SYMBOL(peernet2id); 282 283/* This function returns true is the peer netns has an id assigned into the 284 * current netns. 285 */ 286bool peernet_has_id(const struct net *net, struct net *peer) 287{ 288 return peernet2id(net, peer) >= 0; 289} 290 291struct net *get_net_ns_by_id(const struct net *net, int id) 292{ 293 struct net *peer; 294 295 if (id < 0) 296 return NULL; 297 298 rcu_read_lock(); 299 peer = idr_find(&net->netns_ids, id); 300 if (peer) 301 peer = maybe_get_net(peer); 302 rcu_read_unlock(); 303 304 return peer; 305} 306EXPORT_SYMBOL_GPL(get_net_ns_by_id); 307 308/* init code that must occur even if setup_net() is not called. */ 309static __net_init void preinit_net(struct net *net) 310{ 311 ref_tracker_dir_init(&net->notrefcnt_tracker, 128, "net notrefcnt"); 312} 313 314/* 315 * setup_net runs the initializers for the network namespace object. 316 */ 317static __net_init int setup_net(struct net *net, struct user_namespace *user_ns) 318{ 319 /* Must be called with pernet_ops_rwsem held */ 320 const struct pernet_operations *ops, *saved_ops; 321 LIST_HEAD(net_exit_list); 322 LIST_HEAD(dev_kill_list); 323 int error = 0; 324 325 refcount_set(&net->ns.count, 1); 326 ref_tracker_dir_init(&net->refcnt_tracker, 128, "net refcnt"); 327 328 refcount_set(&net->passive, 1); 329 get_random_bytes(&net->hash_mix, sizeof(u32)); 330 preempt_disable(); 331 net->net_cookie = gen_cookie_next(&net_cookie); 332 preempt_enable(); 333 net->dev_base_seq = 1; 334 net->user_ns = user_ns; 335 idr_init(&net->netns_ids); 336 spin_lock_init(&net->nsid_lock); 337 mutex_init(&net->ipv4.ra_mutex); 338 339 list_for_each_entry(ops, &pernet_list, list) { 340 error = ops_init(ops, net); 341 if (error < 0) 342 goto out_undo; 343 } 344 down_write(&net_rwsem); 345 list_add_tail_rcu(&net->list, &net_namespace_list); 346 up_write(&net_rwsem); 347out: 348 return error; 349 350out_undo: 351 /* Walk through the list backwards calling the exit functions 352 * for the pernet modules whose init functions did not fail. 353 */ 354 list_add(&net->exit_list, &net_exit_list); 355 saved_ops = ops; 356 list_for_each_entry_continue_reverse(ops, &pernet_list, list) 357 ops_pre_exit_list(ops, &net_exit_list); 358 359 synchronize_rcu(); 360 361 ops = saved_ops; 362 rtnl_lock(); 363 list_for_each_entry_continue_reverse(ops, &pernet_list, list) { 364 if (ops->exit_batch_rtnl) 365 ops->exit_batch_rtnl(&net_exit_list, &dev_kill_list); 366 } 367 unregister_netdevice_many(&dev_kill_list); 368 rtnl_unlock(); 369 370 ops = saved_ops; 371 list_for_each_entry_continue_reverse(ops, &pernet_list, list) 372 ops_exit_list(ops, &net_exit_list); 373 374 ops = saved_ops; 375 list_for_each_entry_continue_reverse(ops, &pernet_list, list) 376 ops_free_list(ops, &net_exit_list); 377 378 rcu_barrier(); 379 goto out; 380} 381 382static int __net_init net_defaults_init_net(struct net *net) 383{ 384 net->core.sysctl_somaxconn = SOMAXCONN; 385 /* Limits per socket sk_omem_alloc usage. 386 * TCP zerocopy regular usage needs 128 KB. 387 */ 388 net->core.sysctl_optmem_max = 128 * 1024; 389 net->core.sysctl_txrehash = SOCK_TXREHASH_ENABLED; 390 391 return 0; 392} 393 394static struct pernet_operations net_defaults_ops = { 395 .init = net_defaults_init_net, 396}; 397 398static __init int net_defaults_init(void) 399{ 400 if (register_pernet_subsys(&net_defaults_ops)) 401 panic("Cannot initialize net default settings"); 402 403 return 0; 404} 405 406core_initcall(net_defaults_init); 407 408#ifdef CONFIG_NET_NS 409static struct ucounts *inc_net_namespaces(struct user_namespace *ns) 410{ 411 return inc_ucount(ns, current_euid(), UCOUNT_NET_NAMESPACES); 412} 413 414static void dec_net_namespaces(struct ucounts *ucounts) 415{ 416 dec_ucount(ucounts, UCOUNT_NET_NAMESPACES); 417} 418 419static struct kmem_cache *net_cachep __ro_after_init; 420static struct workqueue_struct *netns_wq; 421 422static struct net *net_alloc(void) 423{ 424 struct net *net = NULL; 425 struct net_generic *ng; 426 427 ng = net_alloc_generic(); 428 if (!ng) 429 goto out; 430 431 net = kmem_cache_zalloc(net_cachep, GFP_KERNEL); 432 if (!net) 433 goto out_free; 434 435#ifdef CONFIG_KEYS 436 net->key_domain = kzalloc(sizeof(struct key_tag), GFP_KERNEL); 437 if (!net->key_domain) 438 goto out_free_2; 439 refcount_set(&net->key_domain->usage, 1); 440#endif 441 442 rcu_assign_pointer(net->gen, ng); 443out: 444 return net; 445 446#ifdef CONFIG_KEYS 447out_free_2: 448 kmem_cache_free(net_cachep, net); 449 net = NULL; 450#endif 451out_free: 452 kfree(ng); 453 goto out; 454} 455 456static void net_free(struct net *net) 457{ 458 if (refcount_dec_and_test(&net->passive)) { 459 kfree(rcu_access_pointer(net->gen)); 460 461 /* There should not be any trackers left there. */ 462 ref_tracker_dir_exit(&net->notrefcnt_tracker); 463 464 kmem_cache_free(net_cachep, net); 465 } 466} 467 468void net_drop_ns(void *p) 469{ 470 struct net *net = (struct net *)p; 471 472 if (net) 473 net_free(net); 474} 475 476struct net *copy_net_ns(unsigned long flags, 477 struct user_namespace *user_ns, struct net *old_net) 478{ 479 struct ucounts *ucounts; 480 struct net *net; 481 int rv; 482 483 if (!(flags & CLONE_NEWNET)) 484 return get_net(old_net); 485 486 ucounts = inc_net_namespaces(user_ns); 487 if (!ucounts) 488 return ERR_PTR(-ENOSPC); 489 490 net = net_alloc(); 491 if (!net) { 492 rv = -ENOMEM; 493 goto dec_ucounts; 494 } 495 496 preinit_net(net); 497 refcount_set(&net->passive, 1); 498 net->ucounts = ucounts; 499 get_user_ns(user_ns); 500 501 rv = down_read_killable(&pernet_ops_rwsem); 502 if (rv < 0) 503 goto put_userns; 504 505 rv = setup_net(net, user_ns); 506 507 up_read(&pernet_ops_rwsem); 508 509 if (rv < 0) { 510put_userns: 511#ifdef CONFIG_KEYS 512 key_remove_domain(net->key_domain); 513#endif 514 put_user_ns(user_ns); 515 net_free(net); 516dec_ucounts: 517 dec_net_namespaces(ucounts); 518 return ERR_PTR(rv); 519 } 520 return net; 521} 522 523/** 524 * net_ns_get_ownership - get sysfs ownership data for @net 525 * @net: network namespace in question (can be NULL) 526 * @uid: kernel user ID for sysfs objects 527 * @gid: kernel group ID for sysfs objects 528 * 529 * Returns the uid/gid pair of root in the user namespace associated with the 530 * given network namespace. 531 */ 532void net_ns_get_ownership(const struct net *net, kuid_t *uid, kgid_t *gid) 533{ 534 if (net) { 535 kuid_t ns_root_uid = make_kuid(net->user_ns, 0); 536 kgid_t ns_root_gid = make_kgid(net->user_ns, 0); 537 538 if (uid_valid(ns_root_uid)) 539 *uid = ns_root_uid; 540 541 if (gid_valid(ns_root_gid)) 542 *gid = ns_root_gid; 543 } else { 544 *uid = GLOBAL_ROOT_UID; 545 *gid = GLOBAL_ROOT_GID; 546 } 547} 548EXPORT_SYMBOL_GPL(net_ns_get_ownership); 549 550static void unhash_nsid(struct net *net, struct net *last) 551{ 552 struct net *tmp; 553 /* This function is only called from cleanup_net() work, 554 * and this work is the only process, that may delete 555 * a net from net_namespace_list. So, when the below 556 * is executing, the list may only grow. Thus, we do not 557 * use for_each_net_rcu() or net_rwsem. 558 */ 559 for_each_net(tmp) { 560 int id; 561 562 spin_lock_bh(&tmp->nsid_lock); 563 id = __peernet2id(tmp, net); 564 if (id >= 0) 565 idr_remove(&tmp->netns_ids, id); 566 spin_unlock_bh(&tmp->nsid_lock); 567 if (id >= 0) 568 rtnl_net_notifyid(tmp, RTM_DELNSID, id, 0, NULL, 569 GFP_KERNEL); 570 if (tmp == last) 571 break; 572 } 573 spin_lock_bh(&net->nsid_lock); 574 idr_destroy(&net->netns_ids); 575 spin_unlock_bh(&net->nsid_lock); 576} 577 578static LLIST_HEAD(cleanup_list); 579 580static void cleanup_net(struct work_struct *work) 581{ 582 const struct pernet_operations *ops; 583 struct net *net, *tmp, *last; 584 struct llist_node *net_kill_list; 585 LIST_HEAD(net_exit_list); 586 LIST_HEAD(dev_kill_list); 587 588 /* Atomically snapshot the list of namespaces to cleanup */ 589 net_kill_list = llist_del_all(&cleanup_list); 590 591 down_read(&pernet_ops_rwsem); 592 593 /* Don't let anyone else find us. */ 594 down_write(&net_rwsem); 595 llist_for_each_entry(net, net_kill_list, cleanup_list) 596 list_del_rcu(&net->list); 597 /* Cache last net. After we unlock rtnl, no one new net 598 * added to net_namespace_list can assign nsid pointer 599 * to a net from net_kill_list (see peernet2id_alloc()). 600 * So, we skip them in unhash_nsid(). 601 * 602 * Note, that unhash_nsid() does not delete nsid links 603 * between net_kill_list's nets, as they've already 604 * deleted from net_namespace_list. But, this would be 605 * useless anyway, as netns_ids are destroyed there. 606 */ 607 last = list_last_entry(&net_namespace_list, struct net, list); 608 up_write(&net_rwsem); 609 610 llist_for_each_entry(net, net_kill_list, cleanup_list) { 611 unhash_nsid(net, last); 612 list_add_tail(&net->exit_list, &net_exit_list); 613 } 614 615 /* Run all of the network namespace pre_exit methods */ 616 list_for_each_entry_reverse(ops, &pernet_list, list) 617 ops_pre_exit_list(ops, &net_exit_list); 618 619 /* 620 * Another CPU might be rcu-iterating the list, wait for it. 621 * This needs to be before calling the exit() notifiers, so 622 * the rcu_barrier() below isn't sufficient alone. 623 * Also the pre_exit() and exit() methods need this barrier. 624 */ 625 synchronize_rcu_expedited(); 626 627 rtnl_lock(); 628 list_for_each_entry_reverse(ops, &pernet_list, list) { 629 if (ops->exit_batch_rtnl) 630 ops->exit_batch_rtnl(&net_exit_list, &dev_kill_list); 631 } 632 unregister_netdevice_many(&dev_kill_list); 633 rtnl_unlock(); 634 635 /* Run all of the network namespace exit methods */ 636 list_for_each_entry_reverse(ops, &pernet_list, list) 637 ops_exit_list(ops, &net_exit_list); 638 639 /* Free the net generic variables */ 640 list_for_each_entry_reverse(ops, &pernet_list, list) 641 ops_free_list(ops, &net_exit_list); 642 643 up_read(&pernet_ops_rwsem); 644 645 /* Ensure there are no outstanding rcu callbacks using this 646 * network namespace. 647 */ 648 rcu_barrier(); 649 650 /* Finally it is safe to free my network namespace structure */ 651 list_for_each_entry_safe(net, tmp, &net_exit_list, exit_list) { 652 list_del_init(&net->exit_list); 653 dec_net_namespaces(net->ucounts); 654#ifdef CONFIG_KEYS 655 key_remove_domain(net->key_domain); 656#endif 657 put_user_ns(net->user_ns); 658 net_free(net); 659 } 660} 661 662/** 663 * net_ns_barrier - wait until concurrent net_cleanup_work is done 664 * 665 * cleanup_net runs from work queue and will first remove namespaces 666 * from the global list, then run net exit functions. 667 * 668 * Call this in module exit path to make sure that all netns 669 * ->exit ops have been invoked before the function is removed. 670 */ 671void net_ns_barrier(void) 672{ 673 down_write(&pernet_ops_rwsem); 674 up_write(&pernet_ops_rwsem); 675} 676EXPORT_SYMBOL(net_ns_barrier); 677 678static DECLARE_WORK(net_cleanup_work, cleanup_net); 679 680void __put_net(struct net *net) 681{ 682 ref_tracker_dir_exit(&net->refcnt_tracker); 683 /* Cleanup the network namespace in process context */ 684 if (llist_add(&net->cleanup_list, &cleanup_list)) 685 queue_work(netns_wq, &net_cleanup_work); 686} 687EXPORT_SYMBOL_GPL(__put_net); 688 689/** 690 * get_net_ns - increment the refcount of the network namespace 691 * @ns: common namespace (net) 692 * 693 * Returns the net's common namespace. 694 */ 695struct ns_common *get_net_ns(struct ns_common *ns) 696{ 697 return &get_net(container_of(ns, struct net, ns))->ns; 698} 699EXPORT_SYMBOL_GPL(get_net_ns); 700 701struct net *get_net_ns_by_fd(int fd) 702{ 703 struct fd f = fdget(fd); 704 struct net *net = ERR_PTR(-EINVAL); 705 706 if (!f.file) 707 return ERR_PTR(-EBADF); 708 709 if (proc_ns_file(f.file)) { 710 struct ns_common *ns = get_proc_ns(file_inode(f.file)); 711 if (ns->ops == &netns_operations) 712 net = get_net(container_of(ns, struct net, ns)); 713 } 714 fdput(f); 715 716 return net; 717} 718EXPORT_SYMBOL_GPL(get_net_ns_by_fd); 719#endif 720 721struct net *get_net_ns_by_pid(pid_t pid) 722{ 723 struct task_struct *tsk; 724 struct net *net; 725 726 /* Lookup the network namespace */ 727 net = ERR_PTR(-ESRCH); 728 rcu_read_lock(); 729 tsk = find_task_by_vpid(pid); 730 if (tsk) { 731 struct nsproxy *nsproxy; 732 task_lock(tsk); 733 nsproxy = tsk->nsproxy; 734 if (nsproxy) 735 net = get_net(nsproxy->net_ns); 736 task_unlock(tsk); 737 } 738 rcu_read_unlock(); 739 return net; 740} 741EXPORT_SYMBOL_GPL(get_net_ns_by_pid); 742 743static __net_init int net_ns_net_init(struct net *net) 744{ 745#ifdef CONFIG_NET_NS 746 net->ns.ops = &netns_operations; 747#endif 748 return ns_alloc_inum(&net->ns); 749} 750 751static __net_exit void net_ns_net_exit(struct net *net) 752{ 753 ns_free_inum(&net->ns); 754} 755 756static struct pernet_operations __net_initdata net_ns_ops = { 757 .init = net_ns_net_init, 758 .exit = net_ns_net_exit, 759}; 760 761static const struct nla_policy rtnl_net_policy[NETNSA_MAX + 1] = { 762 [NETNSA_NONE] = { .type = NLA_UNSPEC }, 763 [NETNSA_NSID] = { .type = NLA_S32 }, 764 [NETNSA_PID] = { .type = NLA_U32 }, 765 [NETNSA_FD] = { .type = NLA_U32 }, 766 [NETNSA_TARGET_NSID] = { .type = NLA_S32 }, 767}; 768 769static int rtnl_net_newid(struct sk_buff *skb, struct nlmsghdr *nlh, 770 struct netlink_ext_ack *extack) 771{ 772 struct net *net = sock_net(skb->sk); 773 struct nlattr *tb[NETNSA_MAX + 1]; 774 struct nlattr *nla; 775 struct net *peer; 776 int nsid, err; 777 778 err = nlmsg_parse_deprecated(nlh, sizeof(struct rtgenmsg), tb, 779 NETNSA_MAX, rtnl_net_policy, extack); 780 if (err < 0) 781 return err; 782 if (!tb[NETNSA_NSID]) { 783 NL_SET_ERR_MSG(extack, "nsid is missing"); 784 return -EINVAL; 785 } 786 nsid = nla_get_s32(tb[NETNSA_NSID]); 787 788 if (tb[NETNSA_PID]) { 789 peer = get_net_ns_by_pid(nla_get_u32(tb[NETNSA_PID])); 790 nla = tb[NETNSA_PID]; 791 } else if (tb[NETNSA_FD]) { 792 peer = get_net_ns_by_fd(nla_get_u32(tb[NETNSA_FD])); 793 nla = tb[NETNSA_FD]; 794 } else { 795 NL_SET_ERR_MSG(extack, "Peer netns reference is missing"); 796 return -EINVAL; 797 } 798 if (IS_ERR(peer)) { 799 NL_SET_BAD_ATTR(extack, nla); 800 NL_SET_ERR_MSG(extack, "Peer netns reference is invalid"); 801 return PTR_ERR(peer); 802 } 803 804 spin_lock_bh(&net->nsid_lock); 805 if (__peernet2id(net, peer) >= 0) { 806 spin_unlock_bh(&net->nsid_lock); 807 err = -EEXIST; 808 NL_SET_BAD_ATTR(extack, nla); 809 NL_SET_ERR_MSG(extack, 810 "Peer netns already has a nsid assigned"); 811 goto out; 812 } 813 814 err = alloc_netid(net, peer, nsid); 815 spin_unlock_bh(&net->nsid_lock); 816 if (err >= 0) { 817 rtnl_net_notifyid(net, RTM_NEWNSID, err, NETLINK_CB(skb).portid, 818 nlh, GFP_KERNEL); 819 err = 0; 820 } else if (err == -ENOSPC && nsid >= 0) { 821 err = -EEXIST; 822 NL_SET_BAD_ATTR(extack, tb[NETNSA_NSID]); 823 NL_SET_ERR_MSG(extack, "The specified nsid is already used"); 824 } 825out: 826 put_net(peer); 827 return err; 828} 829 830static int rtnl_net_get_size(void) 831{ 832 return NLMSG_ALIGN(sizeof(struct rtgenmsg)) 833 + nla_total_size(sizeof(s32)) /* NETNSA_NSID */ 834 + nla_total_size(sizeof(s32)) /* NETNSA_CURRENT_NSID */ 835 ; 836} 837 838struct net_fill_args { 839 u32 portid; 840 u32 seq; 841 int flags; 842 int cmd; 843 int nsid; 844 bool add_ref; 845 int ref_nsid; 846}; 847 848static int rtnl_net_fill(struct sk_buff *skb, struct net_fill_args *args) 849{ 850 struct nlmsghdr *nlh; 851 struct rtgenmsg *rth; 852 853 nlh = nlmsg_put(skb, args->portid, args->seq, args->cmd, sizeof(*rth), 854 args->flags); 855 if (!nlh) 856 return -EMSGSIZE; 857 858 rth = nlmsg_data(nlh); 859 rth->rtgen_family = AF_UNSPEC; 860 861 if (nla_put_s32(skb, NETNSA_NSID, args->nsid)) 862 goto nla_put_failure; 863 864 if (args->add_ref && 865 nla_put_s32(skb, NETNSA_CURRENT_NSID, args->ref_nsid)) 866 goto nla_put_failure; 867 868 nlmsg_end(skb, nlh); 869 return 0; 870 871nla_put_failure: 872 nlmsg_cancel(skb, nlh); 873 return -EMSGSIZE; 874} 875 876static int rtnl_net_valid_getid_req(struct sk_buff *skb, 877 const struct nlmsghdr *nlh, 878 struct nlattr **tb, 879 struct netlink_ext_ack *extack) 880{ 881 int i, err; 882 883 if (!netlink_strict_get_check(skb)) 884 return nlmsg_parse_deprecated(nlh, sizeof(struct rtgenmsg), 885 tb, NETNSA_MAX, rtnl_net_policy, 886 extack); 887 888 err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct rtgenmsg), tb, 889 NETNSA_MAX, rtnl_net_policy, 890 extack); 891 if (err) 892 return err; 893 894 for (i = 0; i <= NETNSA_MAX; i++) { 895 if (!tb[i]) 896 continue; 897 898 switch (i) { 899 case NETNSA_PID: 900 case NETNSA_FD: 901 case NETNSA_NSID: 902 case NETNSA_TARGET_NSID: 903 break; 904 default: 905 NL_SET_ERR_MSG(extack, "Unsupported attribute in peer netns getid request"); 906 return -EINVAL; 907 } 908 } 909 910 return 0; 911} 912 913static int rtnl_net_getid(struct sk_buff *skb, struct nlmsghdr *nlh, 914 struct netlink_ext_ack *extack) 915{ 916 struct net *net = sock_net(skb->sk); 917 struct nlattr *tb[NETNSA_MAX + 1]; 918 struct net_fill_args fillargs = { 919 .portid = NETLINK_CB(skb).portid, 920 .seq = nlh->nlmsg_seq, 921 .cmd = RTM_NEWNSID, 922 }; 923 struct net *peer, *target = net; 924 struct nlattr *nla; 925 struct sk_buff *msg; 926 int err; 927 928 err = rtnl_net_valid_getid_req(skb, nlh, tb, extack); 929 if (err < 0) 930 return err; 931 if (tb[NETNSA_PID]) { 932 peer = get_net_ns_by_pid(nla_get_u32(tb[NETNSA_PID])); 933 nla = tb[NETNSA_PID]; 934 } else if (tb[NETNSA_FD]) { 935 peer = get_net_ns_by_fd(nla_get_u32(tb[NETNSA_FD])); 936 nla = tb[NETNSA_FD]; 937 } else if (tb[NETNSA_NSID]) { 938 peer = get_net_ns_by_id(net, nla_get_s32(tb[NETNSA_NSID])); 939 if (!peer) 940 peer = ERR_PTR(-ENOENT); 941 nla = tb[NETNSA_NSID]; 942 } else { 943 NL_SET_ERR_MSG(extack, "Peer netns reference is missing"); 944 return -EINVAL; 945 } 946 947 if (IS_ERR(peer)) { 948 NL_SET_BAD_ATTR(extack, nla); 949 NL_SET_ERR_MSG(extack, "Peer netns reference is invalid"); 950 return PTR_ERR(peer); 951 } 952 953 if (tb[NETNSA_TARGET_NSID]) { 954 int id = nla_get_s32(tb[NETNSA_TARGET_NSID]); 955 956 target = rtnl_get_net_ns_capable(NETLINK_CB(skb).sk, id); 957 if (IS_ERR(target)) { 958 NL_SET_BAD_ATTR(extack, tb[NETNSA_TARGET_NSID]); 959 NL_SET_ERR_MSG(extack, 960 "Target netns reference is invalid"); 961 err = PTR_ERR(target); 962 goto out; 963 } 964 fillargs.add_ref = true; 965 fillargs.ref_nsid = peernet2id(net, peer); 966 } 967 968 msg = nlmsg_new(rtnl_net_get_size(), GFP_KERNEL); 969 if (!msg) { 970 err = -ENOMEM; 971 goto out; 972 } 973 974 fillargs.nsid = peernet2id(target, peer); 975 err = rtnl_net_fill(msg, &fillargs); 976 if (err < 0) 977 goto err_out; 978 979 err = rtnl_unicast(msg, net, NETLINK_CB(skb).portid); 980 goto out; 981 982err_out: 983 nlmsg_free(msg); 984out: 985 if (fillargs.add_ref) 986 put_net(target); 987 put_net(peer); 988 return err; 989} 990 991struct rtnl_net_dump_cb { 992 struct net *tgt_net; 993 struct net *ref_net; 994 struct sk_buff *skb; 995 struct net_fill_args fillargs; 996 int idx; 997 int s_idx; 998}; 999 1000/* Runs in RCU-critical section. */ 1001static int rtnl_net_dumpid_one(int id, void *peer, void *data) 1002{ 1003 struct rtnl_net_dump_cb *net_cb = (struct rtnl_net_dump_cb *)data; 1004 int ret; 1005 1006 if (net_cb->idx < net_cb->s_idx) 1007 goto cont; 1008 1009 net_cb->fillargs.nsid = id; 1010 if (net_cb->fillargs.add_ref) 1011 net_cb->fillargs.ref_nsid = __peernet2id(net_cb->ref_net, peer); 1012 ret = rtnl_net_fill(net_cb->skb, &net_cb->fillargs); 1013 if (ret < 0) 1014 return ret; 1015 1016cont: 1017 net_cb->idx++; 1018 return 0; 1019} 1020 1021static int rtnl_valid_dump_net_req(const struct nlmsghdr *nlh, struct sock *sk, 1022 struct rtnl_net_dump_cb *net_cb, 1023 struct netlink_callback *cb) 1024{ 1025 struct netlink_ext_ack *extack = cb->extack; 1026 struct nlattr *tb[NETNSA_MAX + 1]; 1027 int err, i; 1028 1029 err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct rtgenmsg), tb, 1030 NETNSA_MAX, rtnl_net_policy, 1031 extack); 1032 if (err < 0) 1033 return err; 1034 1035 for (i = 0; i <= NETNSA_MAX; i++) { 1036 if (!tb[i]) 1037 continue; 1038 1039 if (i == NETNSA_TARGET_NSID) { 1040 struct net *net; 1041 1042 net = rtnl_get_net_ns_capable(sk, nla_get_s32(tb[i])); 1043 if (IS_ERR(net)) { 1044 NL_SET_BAD_ATTR(extack, tb[i]); 1045 NL_SET_ERR_MSG(extack, 1046 "Invalid target network namespace id"); 1047 return PTR_ERR(net); 1048 } 1049 net_cb->fillargs.add_ref = true; 1050 net_cb->ref_net = net_cb->tgt_net; 1051 net_cb->tgt_net = net; 1052 } else { 1053 NL_SET_BAD_ATTR(extack, tb[i]); 1054 NL_SET_ERR_MSG(extack, 1055 "Unsupported attribute in dump request"); 1056 return -EINVAL; 1057 } 1058 } 1059 1060 return 0; 1061} 1062 1063static int rtnl_net_dumpid(struct sk_buff *skb, struct netlink_callback *cb) 1064{ 1065 struct rtnl_net_dump_cb net_cb = { 1066 .tgt_net = sock_net(skb->sk), 1067 .skb = skb, 1068 .fillargs = { 1069 .portid = NETLINK_CB(cb->skb).portid, 1070 .seq = cb->nlh->nlmsg_seq, 1071 .flags = NLM_F_MULTI, 1072 .cmd = RTM_NEWNSID, 1073 }, 1074 .idx = 0, 1075 .s_idx = cb->args[0], 1076 }; 1077 int err = 0; 1078 1079 if (cb->strict_check) { 1080 err = rtnl_valid_dump_net_req(cb->nlh, skb->sk, &net_cb, cb); 1081 if (err < 0) 1082 goto end; 1083 } 1084 1085 rcu_read_lock(); 1086 idr_for_each(&net_cb.tgt_net->netns_ids, rtnl_net_dumpid_one, &net_cb); 1087 rcu_read_unlock(); 1088 1089 cb->args[0] = net_cb.idx; 1090end: 1091 if (net_cb.fillargs.add_ref) 1092 put_net(net_cb.tgt_net); 1093 return err < 0 ? err : skb->len; 1094} 1095 1096static void rtnl_net_notifyid(struct net *net, int cmd, int id, u32 portid, 1097 struct nlmsghdr *nlh, gfp_t gfp) 1098{ 1099 struct net_fill_args fillargs = { 1100 .portid = portid, 1101 .seq = nlh ? nlh->nlmsg_seq : 0, 1102 .cmd = cmd, 1103 .nsid = id, 1104 }; 1105 struct sk_buff *msg; 1106 int err = -ENOMEM; 1107 1108 msg = nlmsg_new(rtnl_net_get_size(), gfp); 1109 if (!msg) 1110 goto out; 1111 1112 err = rtnl_net_fill(msg, &fillargs); 1113 if (err < 0) 1114 goto err_out; 1115 1116 rtnl_notify(msg, net, portid, RTNLGRP_NSID, nlh, gfp); 1117 return; 1118 1119err_out: 1120 nlmsg_free(msg); 1121out: 1122 rtnl_set_sk_err(net, RTNLGRP_NSID, err); 1123} 1124 1125#ifdef CONFIG_NET_NS 1126static void __init netns_ipv4_struct_check(void) 1127{ 1128 /* TX readonly hotpath cache lines */ 1129 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_tx, 1130 sysctl_tcp_early_retrans); 1131 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_tx, 1132 sysctl_tcp_tso_win_divisor); 1133 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_tx, 1134 sysctl_tcp_tso_rtt_log); 1135 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_tx, 1136 sysctl_tcp_autocorking); 1137 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_tx, 1138 sysctl_tcp_min_snd_mss); 1139 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_tx, 1140 sysctl_tcp_notsent_lowat); 1141 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_tx, 1142 sysctl_tcp_limit_output_bytes); 1143 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_tx, 1144 sysctl_tcp_min_rtt_wlen); 1145 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_tx, 1146 sysctl_tcp_wmem); 1147 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_tx, 1148 sysctl_ip_fwd_use_pmtu); 1149 CACHELINE_ASSERT_GROUP_SIZE(struct netns_ipv4, netns_ipv4_read_tx, 33); 1150 1151 /* TXRX readonly hotpath cache lines */ 1152 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_txrx, 1153 sysctl_tcp_moderate_rcvbuf); 1154 CACHELINE_ASSERT_GROUP_SIZE(struct netns_ipv4, netns_ipv4_read_txrx, 1); 1155 1156 /* RX readonly hotpath cache line */ 1157 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_rx, 1158 sysctl_ip_early_demux); 1159 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_rx, 1160 sysctl_tcp_early_demux); 1161 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_rx, 1162 sysctl_tcp_reordering); 1163 CACHELINE_ASSERT_GROUP_MEMBER(struct netns_ipv4, netns_ipv4_read_rx, 1164 sysctl_tcp_rmem); 1165 CACHELINE_ASSERT_GROUP_SIZE(struct netns_ipv4, netns_ipv4_read_rx, 18); 1166} 1167#endif 1168 1169void __init net_ns_init(void) 1170{ 1171 struct net_generic *ng; 1172 1173#ifdef CONFIG_NET_NS 1174 netns_ipv4_struct_check(); 1175 net_cachep = kmem_cache_create("net_namespace", sizeof(struct net), 1176 SMP_CACHE_BYTES, 1177 SLAB_PANIC|SLAB_ACCOUNT, NULL); 1178 1179 /* Create workqueue for cleanup */ 1180 netns_wq = create_singlethread_workqueue("netns"); 1181 if (!netns_wq) 1182 panic("Could not create netns workq"); 1183#endif 1184 1185 ng = net_alloc_generic(); 1186 if (!ng) 1187 panic("Could not allocate generic netns"); 1188 1189 rcu_assign_pointer(init_net.gen, ng); 1190 1191#ifdef CONFIG_KEYS 1192 init_net.key_domain = &init_net_key_domain; 1193#endif 1194 down_write(&pernet_ops_rwsem); 1195 preinit_net(&init_net); 1196 if (setup_net(&init_net, &init_user_ns)) 1197 panic("Could not setup the initial network namespace"); 1198 1199 init_net_initialized = true; 1200 up_write(&pernet_ops_rwsem); 1201 1202 if (register_pernet_subsys(&net_ns_ops)) 1203 panic("Could not register network namespace subsystems"); 1204 1205 rtnl_register(PF_UNSPEC, RTM_NEWNSID, rtnl_net_newid, NULL, 1206 RTNL_FLAG_DOIT_UNLOCKED); 1207 rtnl_register(PF_UNSPEC, RTM_GETNSID, rtnl_net_getid, rtnl_net_dumpid, 1208 RTNL_FLAG_DOIT_UNLOCKED); 1209} 1210 1211static void free_exit_list(struct pernet_operations *ops, struct list_head *net_exit_list) 1212{ 1213 ops_pre_exit_list(ops, net_exit_list); 1214 synchronize_rcu(); 1215 1216 if (ops->exit_batch_rtnl) { 1217 LIST_HEAD(dev_kill_list); 1218 1219 rtnl_lock(); 1220 ops->exit_batch_rtnl(net_exit_list, &dev_kill_list); 1221 unregister_netdevice_many(&dev_kill_list); 1222 rtnl_unlock(); 1223 } 1224 ops_exit_list(ops, net_exit_list); 1225 1226 ops_free_list(ops, net_exit_list); 1227} 1228 1229#ifdef CONFIG_NET_NS 1230static int __register_pernet_operations(struct list_head *list, 1231 struct pernet_operations *ops) 1232{ 1233 struct net *net; 1234 int error; 1235 LIST_HEAD(net_exit_list); 1236 1237 list_add_tail(&ops->list, list); 1238 if (ops->init || (ops->id && ops->size)) { 1239 /* We held write locked pernet_ops_rwsem, and parallel 1240 * setup_net() and cleanup_net() are not possible. 1241 */ 1242 for_each_net(net) { 1243 error = ops_init(ops, net); 1244 if (error) 1245 goto out_undo; 1246 list_add_tail(&net->exit_list, &net_exit_list); 1247 } 1248 } 1249 return 0; 1250 1251out_undo: 1252 /* If I have an error cleanup all namespaces I initialized */ 1253 list_del(&ops->list); 1254 free_exit_list(ops, &net_exit_list); 1255 return error; 1256} 1257 1258static void __unregister_pernet_operations(struct pernet_operations *ops) 1259{ 1260 struct net *net; 1261 LIST_HEAD(net_exit_list); 1262 1263 list_del(&ops->list); 1264 /* See comment in __register_pernet_operations() */ 1265 for_each_net(net) 1266 list_add_tail(&net->exit_list, &net_exit_list); 1267 1268 free_exit_list(ops, &net_exit_list); 1269} 1270 1271#else 1272 1273static int __register_pernet_operations(struct list_head *list, 1274 struct pernet_operations *ops) 1275{ 1276 if (!init_net_initialized) { 1277 list_add_tail(&ops->list, list); 1278 return 0; 1279 } 1280 1281 return ops_init(ops, &init_net); 1282} 1283 1284static void __unregister_pernet_operations(struct pernet_operations *ops) 1285{ 1286 if (!init_net_initialized) { 1287 list_del(&ops->list); 1288 } else { 1289 LIST_HEAD(net_exit_list); 1290 list_add(&init_net.exit_list, &net_exit_list); 1291 free_exit_list(ops, &net_exit_list); 1292 } 1293} 1294 1295#endif /* CONFIG_NET_NS */ 1296 1297static DEFINE_IDA(net_generic_ids); 1298 1299static int register_pernet_operations(struct list_head *list, 1300 struct pernet_operations *ops) 1301{ 1302 int error; 1303 1304 if (ops->id) { 1305 error = ida_alloc_min(&net_generic_ids, MIN_PERNET_OPS_ID, 1306 GFP_KERNEL); 1307 if (error < 0) 1308 return error; 1309 *ops->id = error; 1310 max_gen_ptrs = max(max_gen_ptrs, *ops->id + 1); 1311 } 1312 error = __register_pernet_operations(list, ops); 1313 if (error) { 1314 rcu_barrier(); 1315 if (ops->id) 1316 ida_free(&net_generic_ids, *ops->id); 1317 } 1318 1319 return error; 1320} 1321 1322static void unregister_pernet_operations(struct pernet_operations *ops) 1323{ 1324 __unregister_pernet_operations(ops); 1325 rcu_barrier(); 1326 if (ops->id) 1327 ida_free(&net_generic_ids, *ops->id); 1328} 1329 1330/** 1331 * register_pernet_subsys - register a network namespace subsystem 1332 * @ops: pernet operations structure for the subsystem 1333 * 1334 * Register a subsystem which has init and exit functions 1335 * that are called when network namespaces are created and 1336 * destroyed respectively. 1337 * 1338 * When registered all network namespace init functions are 1339 * called for every existing network namespace. Allowing kernel 1340 * modules to have a race free view of the set of network namespaces. 1341 * 1342 * When a new network namespace is created all of the init 1343 * methods are called in the order in which they were registered. 1344 * 1345 * When a network namespace is destroyed all of the exit methods 1346 * are called in the reverse of the order with which they were 1347 * registered. 1348 */ 1349int register_pernet_subsys(struct pernet_operations *ops) 1350{ 1351 int error; 1352 down_write(&pernet_ops_rwsem); 1353 error = register_pernet_operations(first_device, ops); 1354 up_write(&pernet_ops_rwsem); 1355 return error; 1356} 1357EXPORT_SYMBOL_GPL(register_pernet_subsys); 1358 1359/** 1360 * unregister_pernet_subsys - unregister a network namespace subsystem 1361 * @ops: pernet operations structure to manipulate 1362 * 1363 * Remove the pernet operations structure from the list to be 1364 * used when network namespaces are created or destroyed. In 1365 * addition run the exit method for all existing network 1366 * namespaces. 1367 */ 1368void unregister_pernet_subsys(struct pernet_operations *ops) 1369{ 1370 down_write(&pernet_ops_rwsem); 1371 unregister_pernet_operations(ops); 1372 up_write(&pernet_ops_rwsem); 1373} 1374EXPORT_SYMBOL_GPL(unregister_pernet_subsys); 1375 1376/** 1377 * register_pernet_device - register a network namespace device 1378 * @ops: pernet operations structure for the subsystem 1379 * 1380 * Register a device which has init and exit functions 1381 * that are called when network namespaces are created and 1382 * destroyed respectively. 1383 * 1384 * When registered all network namespace init functions are 1385 * called for every existing network namespace. Allowing kernel 1386 * modules to have a race free view of the set of network namespaces. 1387 * 1388 * When a new network namespace is created all of the init 1389 * methods are called in the order in which they were registered. 1390 * 1391 * When a network namespace is destroyed all of the exit methods 1392 * are called in the reverse of the order with which they were 1393 * registered. 1394 */ 1395int register_pernet_device(struct pernet_operations *ops) 1396{ 1397 int error; 1398 down_write(&pernet_ops_rwsem); 1399 error = register_pernet_operations(&pernet_list, ops); 1400 if (!error && (first_device == &pernet_list)) 1401 first_device = &ops->list; 1402 up_write(&pernet_ops_rwsem); 1403 return error; 1404} 1405EXPORT_SYMBOL_GPL(register_pernet_device); 1406 1407/** 1408 * unregister_pernet_device - unregister a network namespace netdevice 1409 * @ops: pernet operations structure to manipulate 1410 * 1411 * Remove the pernet operations structure from the list to be 1412 * used when network namespaces are created or destroyed. In 1413 * addition run the exit method for all existing network 1414 * namespaces. 1415 */ 1416void unregister_pernet_device(struct pernet_operations *ops) 1417{ 1418 down_write(&pernet_ops_rwsem); 1419 if (&ops->list == first_device) 1420 first_device = first_device->next; 1421 unregister_pernet_operations(ops); 1422 up_write(&pernet_ops_rwsem); 1423} 1424EXPORT_SYMBOL_GPL(unregister_pernet_device); 1425 1426#ifdef CONFIG_NET_NS 1427static struct ns_common *netns_get(struct task_struct *task) 1428{ 1429 struct net *net = NULL; 1430 struct nsproxy *nsproxy; 1431 1432 task_lock(task); 1433 nsproxy = task->nsproxy; 1434 if (nsproxy) 1435 net = get_net(nsproxy->net_ns); 1436 task_unlock(task); 1437 1438 return net ? &net->ns : NULL; 1439} 1440 1441static inline struct net *to_net_ns(struct ns_common *ns) 1442{ 1443 return container_of(ns, struct net, ns); 1444} 1445 1446static void netns_put(struct ns_common *ns) 1447{ 1448 put_net(to_net_ns(ns)); 1449} 1450 1451static int netns_install(struct nsset *nsset, struct ns_common *ns) 1452{ 1453 struct nsproxy *nsproxy = nsset->nsproxy; 1454 struct net *net = to_net_ns(ns); 1455 1456 if (!ns_capable(net->user_ns, CAP_SYS_ADMIN) || 1457 !ns_capable(nsset->cred->user_ns, CAP_SYS_ADMIN)) 1458 return -EPERM; 1459 1460 put_net(nsproxy->net_ns); 1461 nsproxy->net_ns = get_net(net); 1462 return 0; 1463} 1464 1465static struct user_namespace *netns_owner(struct ns_common *ns) 1466{ 1467 return to_net_ns(ns)->user_ns; 1468} 1469 1470const struct proc_ns_operations netns_operations = { 1471 .name = "net", 1472 .type = CLONE_NEWNET, 1473 .get = netns_get, 1474 .put = netns_put, 1475 .install = netns_install, 1476 .owner = netns_owner, 1477}; 1478#endif 1479