net/mptcp/pm_netlink.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Multipath TCP
   3  *
   4  * Copyright (c) 2020, Red Hat, Inc.
   5  */
   6
   7 #define pr_fmt(fmt) "MPTCP: " fmt
   8
   9 #include <linux/inet.h>
  10 #include <linux/kernel.h>
  11 #include <net/tcp.h>
  12 #include <net/netns/generic.h>
  13 #include <net/mptcp.h>
  14 #include <net/genetlink.h>
  15 #include <uapi/linux/mptcp.h>
  16
  17 #include "protocol.h"
  18 #include "mib.h"
  19
  20 /* forward declaration */
  21 static struct genl_family mptcp_genl_family;
  22
  23 static int pm_nl_pernet_id;
  24
  25 struct mptcp_pm_addr_entry {
  26         struct list_head        list;
  27         struct mptcp_addr_info  addr;
  28         u8                      flags;
  29         int                     ifindex;
  30         struct rcu_head         rcu;
  31         struct socket           *lsk;
  32 };
  33
  34 struct mptcp_pm_add_entry {
  35         struct list_head        list;
  36         struct mptcp_addr_info  addr;
  37         struct timer_list       add_timer;
  38         struct mptcp_sock       *sock;
  39         u8                      retrans_times;
  40 };
  41
  42 #define MAX_ADDR_ID             255
  43 #define BITMAP_SZ DIV_ROUND_UP(MAX_ADDR_ID + 1, BITS_PER_LONG)
  44
  45 struct pm_nl_pernet {
  46         /* protects pernet updates */
  47         spinlock_t              lock;
  48         struct list_head        local_addr_list;
  49         unsigned int            addrs;
  50         unsigned int            add_addr_signal_max;
  51         unsigned int            add_addr_accept_max;
  52         unsigned int            local_addr_max;
  53         unsigned int            subflows_max;
  54         unsigned int            next_id;
  55         unsigned long           id_bitmap[BITMAP_SZ];
  56 };
  57
  58 #define MPTCP_PM_ADDR_MAX       8
  59 #define ADD_ADDR_RETRANS_MAX    3
  60
  61 static bool addresses_equal(const struct mptcp_addr_info *a,
  62                             struct mptcp_addr_info *b, bool use_port)
  63 {
  64         bool addr_equals = false;
  65
  66         if (a->family == b->family) {
  67                 if (a->family == AF_INET)
  68                         addr_equals = a->addr.s_addr == b->addr.s_addr;
  69 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
  70                 else
  71                         addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6);
  72         } else if (a->family == AF_INET) {
  73                 if (ipv6_addr_v4mapped(&b->addr6))
  74                         addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3];
  75         } else if (b->family == AF_INET) {
  76                 if (ipv6_addr_v4mapped(&a->addr6))
  77                         addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr;
  78 #endif
  79         }
  80
  81         if (!addr_equals)
  82                 return false;
  83         if (!use_port)
  84                 return true;
  85
  86         return a->port == b->port;
  87 }
  88
  89 static bool address_zero(const struct mptcp_addr_info *addr)
  90 {
  91         struct mptcp_addr_info zero;
  92
  93         memset(&zero, 0, sizeof(zero));
  94         zero.family = addr->family;
  95
  96         return addresses_equal(addr, &zero, true);
  97 }
  98
  99 static void local_address(const struct sock_common *skc,
 100                           struct mptcp_addr_info *addr)
 101 {
 102         addr->family = skc->skc_family;
 103         addr->port = htons(skc->skc_num);
 104         if (addr->family == AF_INET)
 105                 addr->addr.s_addr = skc->skc_rcv_saddr;
 106 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
 107         else if (addr->family == AF_INET6)
 108                 addr->addr6 = skc->skc_v6_rcv_saddr;
 109 #endif
 110 }
 111
 112 static void remote_address(const struct sock_common *skc,
 113                            struct mptcp_addr_info *addr)
 114 {
 115         addr->family = skc->skc_family;
 116         addr->port = skc->skc_dport;
 117         if (addr->family == AF_INET)
 118                 addr->addr.s_addr = skc->skc_daddr;
 119 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
 120         else if (addr->family == AF_INET6)
 121                 addr->addr6 = skc->skc_v6_daddr;
 122 #endif
 123 }
 124
 125 static bool lookup_subflow_by_saddr(const struct list_head *list,
 126                                     struct mptcp_addr_info *saddr)
 127 {
 128         struct mptcp_subflow_context *subflow;
 129         struct mptcp_addr_info cur;
 130         struct sock_common *skc;
 131
 132         list_for_each_entry(subflow, list, node) {
 133                 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow);
 134
 135                 local_address(skc, &cur);
 136                 if (addresses_equal(&cur, saddr, saddr->port))
 137                         return true;
 138         }
 139
 140         return false;
 141 }
 142
 143 static bool lookup_subflow_by_daddr(const struct list_head *list,
 144                                     struct mptcp_addr_info *daddr)
 145 {
 146         struct mptcp_subflow_context *subflow;
 147         struct mptcp_addr_info cur;
 148         struct sock_common *skc;
 149
 150         list_for_each_entry(subflow, list, node) {
 151                 skc = (struct sock_common *)mptcp_subflow_tcp_sock(subflow);
 152
 153                 remote_address(skc, &cur);
 154                 if (addresses_equal(&cur, daddr, daddr->port))
 155                         return true;
 156         }
 157
 158         return false;
 159 }
 160
 161 static struct mptcp_pm_addr_entry *
 162 select_local_address(const struct pm_nl_pernet *pernet,
 163                      struct mptcp_sock *msk)
 164 {
 165         struct mptcp_pm_addr_entry *entry, *ret = NULL;
 166         struct sock *sk = (struct sock *)msk;
 167
 168         msk_owned_by_me(msk);
 169
 170         rcu_read_lock();
 171         __mptcp_flush_join_list(msk);
 172         list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
 173                 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW))
 174                         continue;
 175
 176                 if (entry->addr.family != sk->sk_family) {
 177 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
 178                         if ((entry->addr.family == AF_INET &&
 179                              !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) ||
 180                             (sk->sk_family == AF_INET &&
 181                              !ipv6_addr_v4mapped(&entry->addr.addr6)))
 182 #endif
 183                                 continue;
 184                 }
 185
 186                 /* avoid any address already in use by subflows and
 187                  * pending join
 188                  */
 189                 if (!lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) {
 190                         ret = entry;
 191                         break;
 192                 }
 193         }
 194         rcu_read_unlock();
 195         return ret;
 196 }
 197
 198 static struct mptcp_pm_addr_entry *
 199 select_signal_address(struct pm_nl_pernet *pernet, unsigned int pos)
 200 {
 201         struct mptcp_pm_addr_entry *entry, *ret = NULL;
 202         int i = 0;
 203
 204         rcu_read_lock();
 205         /* do not keep any additional per socket state, just signal
 206          * the address list in order.
 207          * Note: removal from the local address list during the msk life-cycle
 208          * can lead to additional addresses not being announced.
 209          */
 210         list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
 211                 if (!(entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL))
 212                         continue;
 213                 if (i++ == pos) {
 214                         ret = entry;
 215                         break;
 216                 }
 217         }
 218         rcu_read_unlock();
 219         return ret;
 220 }
 221
 222 unsigned int mptcp_pm_get_add_addr_signal_max(struct mptcp_sock *msk)
 223 {
 224         struct pm_nl_pernet *pernet;
 225
 226         pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
 227         return READ_ONCE(pernet->add_addr_signal_max);
 228 }
 229 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_signal_max);
 230
 231 unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk)
 232 {
 233         struct pm_nl_pernet *pernet;
 234
 235         pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
 236         return READ_ONCE(pernet->add_addr_accept_max);
 237 }
 238 EXPORT_SYMBOL_GPL(mptcp_pm_get_add_addr_accept_max);
 239
 240 unsigned int mptcp_pm_get_subflows_max(struct mptcp_sock *msk)
 241 {
 242         struct pm_nl_pernet *pernet;
 243
 244         pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
 245         return READ_ONCE(pernet->subflows_max);
 246 }
 247 EXPORT_SYMBOL_GPL(mptcp_pm_get_subflows_max);
 248
 249 unsigned int mptcp_pm_get_local_addr_max(struct mptcp_sock *msk)
 250 {
 251         struct pm_nl_pernet *pernet;
 252
 253         pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
 254         return READ_ONCE(pernet->local_addr_max);
 255 }
 256 EXPORT_SYMBOL_GPL(mptcp_pm_get_local_addr_max);
 257
 258 static void check_work_pending(struct mptcp_sock *msk)
 259 {
 260         if (msk->pm.add_addr_signaled == mptcp_pm_get_add_addr_signal_max(msk) &&
 261             (msk->pm.local_addr_used == mptcp_pm_get_local_addr_max(msk) ||
 262              msk->pm.subflows == mptcp_pm_get_subflows_max(msk)))
 263                 WRITE_ONCE(msk->pm.work_pending, false);
 264 }
 265
 266 struct mptcp_pm_add_entry *
 267 mptcp_lookup_anno_list_by_saddr(struct mptcp_sock *msk,
 268                                 struct mptcp_addr_info *addr)
 269 {
 270         struct mptcp_pm_add_entry *entry;
 271
 272         lockdep_assert_held(&msk->pm.lock);
 273
 274         list_for_each_entry(entry, &msk->pm.anno_list, list) {
 275                 if (addresses_equal(&entry->addr, addr, true))
 276                         return entry;
 277         }
 278
 279         return NULL;
 280 }
 281
 282 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk)
 283 {
 284         struct mptcp_pm_add_entry *entry;
 285         struct mptcp_addr_info saddr;
 286         bool ret = false;
 287
 288         local_address((struct sock_common *)sk, &saddr);
 289
 290         spin_lock_bh(&msk->pm.lock);
 291         list_for_each_entry(entry, &msk->pm.anno_list, list) {
 292                 if (addresses_equal(&entry->addr, &saddr, true)) {
 293                         ret = true;
 294                         goto out;
 295                 }
 296         }
 297
 298 out:
 299         spin_unlock_bh(&msk->pm.lock);
 300         return ret;
 301 }
 302
 303 static void mptcp_pm_add_timer(struct timer_list *timer)
 304 {
 305         struct mptcp_pm_add_entry *entry = from_timer(entry, timer, add_timer);
 306         struct mptcp_sock *msk = entry->sock;
 307         struct sock *sk = (struct sock *)msk;
 308
 309         pr_debug("msk=%p", msk);
 310
 311         if (!msk)
 312                 return;
 313
 314         if (inet_sk_state_load(sk) == TCP_CLOSE)
 315                 return;
 316
 317         if (!entry->addr.id)
 318                 return;
 319
 320         if (mptcp_pm_should_add_signal(msk)) {
 321                 sk_reset_timer(sk, timer, jiffies + TCP_RTO_MAX / 8);
 322                 goto out;
 323         }
 324
 325         spin_lock_bh(&msk->pm.lock);
 326
 327         if (!mptcp_pm_should_add_signal(msk)) {
 328                 pr_debug("retransmit ADD_ADDR id=%d", entry->addr.id);
 329                 mptcp_pm_announce_addr(msk, &entry->addr, false);
 330                 mptcp_pm_add_addr_send_ack(msk);
 331                 entry->retrans_times++;
 332         }
 333
 334         if (entry->retrans_times < ADD_ADDR_RETRANS_MAX)
 335                 sk_reset_timer(sk, timer,
 336                                jiffies + mptcp_get_add_addr_timeout(sock_net(sk)));
 337
 338         spin_unlock_bh(&msk->pm.lock);
 339
 340         if (entry->retrans_times == ADD_ADDR_RETRANS_MAX)
 341                 mptcp_pm_subflow_established(msk);
 342
 343 out:
 344         __sock_put(sk);
 345 }
 346
 347 struct mptcp_pm_add_entry *
 348 mptcp_pm_del_add_timer(struct mptcp_sock *msk,
 349                        struct mptcp_addr_info *addr)
 350 {
 351         struct mptcp_pm_add_entry *entry;
 352         struct sock *sk = (struct sock *)msk;
 353
 354         spin_lock_bh(&msk->pm.lock);
 355         entry = mptcp_lookup_anno_list_by_saddr(msk, addr);
 356         if (entry)
 357                 entry->retrans_times = ADD_ADDR_RETRANS_MAX;
 358         spin_unlock_bh(&msk->pm.lock);
 359
 360         if (entry)
 361                 sk_stop_timer_sync(sk, &entry->add_timer);
 362
 363         return entry;
 364 }
 365
 366 static bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
 367                                      struct mptcp_pm_addr_entry *entry)
 368 {
 369         struct mptcp_pm_add_entry *add_entry = NULL;
 370         struct sock *sk = (struct sock *)msk;
 371         struct net *net = sock_net(sk);
 372
 373         lockdep_assert_held(&msk->pm.lock);
 374
 375         if (mptcp_lookup_anno_list_by_saddr(msk, &entry->addr))
 376                 return false;
 377
 378         add_entry = kmalloc(sizeof(*add_entry), GFP_ATOMIC);
 379         if (!add_entry)
 380                 return false;
 381
 382         list_add(&add_entry->list, &msk->pm.anno_list);
 383
 384         add_entry->addr = entry->addr;
 385         add_entry->sock = msk;
 386         add_entry->retrans_times = 0;
 387
 388         timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0);
 389         sk_reset_timer(sk, &add_entry->add_timer,
 390                        jiffies + mptcp_get_add_addr_timeout(net));
 391
 392         return true;
 393 }
 394
 395 void mptcp_pm_free_anno_list(struct mptcp_sock *msk)
 396 {
 397         struct mptcp_pm_add_entry *entry, *tmp;
 398         struct sock *sk = (struct sock *)msk;
 399         LIST_HEAD(free_list);
 400
 401         pr_debug("msk=%p", msk);
 402
 403         spin_lock_bh(&msk->pm.lock);
 404         list_splice_init(&msk->pm.anno_list, &free_list);
 405         spin_unlock_bh(&msk->pm.lock);
 406
 407         list_for_each_entry_safe(entry, tmp, &free_list, list) {
 408                 sk_stop_timer_sync(sk, &entry->add_timer);
 409                 kfree(entry);
 410         }
 411 }
 412
 413 static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk)
 414 {
 415         struct sock *sk = (struct sock *)msk;
 416         struct mptcp_pm_addr_entry *local;
 417         unsigned int add_addr_signal_max;
 418         unsigned int local_addr_max;
 419         struct pm_nl_pernet *pernet;
 420         unsigned int subflows_max;
 421
 422         pernet = net_generic(sock_net(sk), pm_nl_pernet_id);
 423
 424         add_addr_signal_max = mptcp_pm_get_add_addr_signal_max(msk);
 425         local_addr_max = mptcp_pm_get_local_addr_max(msk);
 426         subflows_max = mptcp_pm_get_subflows_max(msk);
 427
 428         pr_debug("local %d:%d signal %d:%d subflows %d:%d\n",
 429                  msk->pm.local_addr_used, local_addr_max,
 430                  msk->pm.add_addr_signaled, add_addr_signal_max,
 431                  msk->pm.subflows, subflows_max);
 432
 433         /* check first for announce */
 434         if (msk->pm.add_addr_signaled < add_addr_signal_max) {
 435                 local = select_signal_address(pernet,
 436                                               msk->pm.add_addr_signaled);
 437
 438                 if (local) {
 439                         if (mptcp_pm_alloc_anno_list(msk, local)) {
 440                                 msk->pm.add_addr_signaled++;
 441                                 mptcp_pm_announce_addr(msk, &local->addr, false);
 442                                 mptcp_pm_nl_addr_send_ack(msk);
 443                         }
 444                 } else {
 445                         /* pick failed, avoid fourther attempts later */
 446                         msk->pm.local_addr_used = add_addr_signal_max;
 447                 }
 448
 449                 check_work_pending(msk);
 450         }
 451
 452         /* check if should create a new subflow */
 453         if (msk->pm.local_addr_used < local_addr_max &&
 454             msk->pm.subflows < subflows_max) {
 455                 local = select_local_address(pernet, msk);
 456                 if (local) {
 457                         struct mptcp_addr_info remote = { 0 };
 458
 459                         msk->pm.local_addr_used++;
 460                         msk->pm.subflows++;
 461                         check_work_pending(msk);
 462                         remote_address((struct sock_common *)sk, &remote);
 463                         spin_unlock_bh(&msk->pm.lock);
 464                         __mptcp_subflow_connect(sk, &local->addr, &remote,
 465                                                 local->flags, local->ifindex);
 466                         spin_lock_bh(&msk->pm.lock);
 467                         return;
 468                 }
 469
 470                 /* lookup failed, avoid fourther attempts later */
 471                 msk->pm.local_addr_used = local_addr_max;
 472                 check_work_pending(msk);
 473         }
 474 }
 475
 476 static void mptcp_pm_nl_fully_established(struct mptcp_sock *msk)
 477 {
 478         mptcp_pm_create_subflow_or_signal_addr(msk);
 479 }
 480
 481 static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk)
 482 {
 483         mptcp_pm_create_subflow_or_signal_addr(msk);
 484 }
 485
 486 static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
 487 {
 488         struct sock *sk = (struct sock *)msk;
 489         unsigned int add_addr_accept_max;
 490         struct mptcp_addr_info remote;
 491         struct mptcp_addr_info local;
 492         unsigned int subflows_max;
 493
 494         add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk);
 495         subflows_max = mptcp_pm_get_subflows_max(msk);
 496
 497         pr_debug("accepted %d:%d remote family %d",
 498                  msk->pm.add_addr_accepted, add_addr_accept_max,
 499                  msk->pm.remote.family);
 500
 501         if (lookup_subflow_by_daddr(&msk->conn_list, &msk->pm.remote))
 502                 goto add_addr_echo;
 503
 504         msk->pm.add_addr_accepted++;
 505         msk->pm.subflows++;
 506         if (msk->pm.add_addr_accepted >= add_addr_accept_max ||
 507             msk->pm.subflows >= subflows_max)
 508                 WRITE_ONCE(msk->pm.accept_addr, false);
 509
 510         /* connect to the specified remote address, using whatever
 511          * local address the routing configuration will pick.
 512          */
 513         remote = msk->pm.remote;
 514         if (!remote.port)
 515                 remote.port = sk->sk_dport;
 516         memset(&local, 0, sizeof(local));
 517         local.family = remote.family;
 518
 519         spin_unlock_bh(&msk->pm.lock);
 520         __mptcp_subflow_connect(sk, &local, &remote, 0, 0);
 521         spin_lock_bh(&msk->pm.lock);
 522
 523 add_addr_echo:
 524         mptcp_pm_announce_addr(msk, &msk->pm.remote, true);
 525         mptcp_pm_nl_addr_send_ack(msk);
 526 }
 527
 528 void mptcp_pm_nl_addr_send_ack(struct mptcp_sock *msk)
 529 {
 530         struct mptcp_subflow_context *subflow;
 531
 532         msk_owned_by_me(msk);
 533         lockdep_assert_held(&msk->pm.lock);
 534
 535         if (!mptcp_pm_should_add_signal(msk) &&
 536             !mptcp_pm_should_rm_signal(msk))
 537                 return;
 538
 539         __mptcp_flush_join_list(msk);
 540         subflow = list_first_entry_or_null(&msk->conn_list, typeof(*subflow), node);
 541         if (subflow) {
 542                 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
 543
 544                 spin_unlock_bh(&msk->pm.lock);
 545                 pr_debug("send ack for %s%s%s",
 546                          mptcp_pm_should_add_signal(msk) ? "add_addr" : "rm_addr",
 547                          mptcp_pm_should_add_signal_ipv6(msk) ? " [ipv6]" : "",
 548                          mptcp_pm_should_add_signal_port(msk) ? " [port]" : "");
 549
 550                 lock_sock(ssk);
 551                 tcp_send_ack(ssk);
 552                 release_sock(ssk);
 553                 spin_lock_bh(&msk->pm.lock);
 554         }
 555 }
 556
 557 int mptcp_pm_nl_mp_prio_send_ack(struct mptcp_sock *msk,
 558                                  struct mptcp_addr_info *addr,
 559                                  u8 bkup)
 560 {
 561         struct mptcp_subflow_context *subflow;
 562
 563         pr_debug("bkup=%d", bkup);
 564
 565         mptcp_for_each_subflow(msk, subflow) {
 566                 struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
 567                 struct sock *sk = (struct sock *)msk;
 568                 struct mptcp_addr_info local;
 569
 570                 local_address((struct sock_common *)ssk, &local);
 571                 if (!addresses_equal(&local, addr, addr->port))
 572                         continue;
 573
 574                 subflow->backup = bkup;
 575                 subflow->send_mp_prio = 1;
 576                 subflow->request_bkup = bkup;
 577                 __MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPPRIOTX);
 578
 579                 spin_unlock_bh(&msk->pm.lock);
 580                 pr_debug("send ack for mp_prio");
 581                 lock_sock(ssk);
 582                 tcp_send_ack(ssk);
 583                 release_sock(ssk);
 584                 spin_lock_bh(&msk->pm.lock);
 585
 586                 return 0;
 587         }
 588
 589         return -EINVAL;
 590 }
 591
 592 static void mptcp_pm_nl_rm_addr_or_subflow(struct mptcp_sock *msk,
 593                                            const struct mptcp_rm_list *rm_list,
 594                                            enum linux_mptcp_mib_field rm_type)
 595 {
 596         struct mptcp_subflow_context *subflow, *tmp;
 597         struct sock *sk = (struct sock *)msk;
 598         u8 i;
 599
 600         pr_debug("%s rm_list_nr %d",
 601                  rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow", rm_list->nr);
 602
 603         msk_owned_by_me(msk);
 604
 605         if (!rm_list->nr)
 606                 return;
 607
 608         if (list_empty(&msk->conn_list))
 609                 return;
 610
 611         for (i = 0; i < rm_list->nr; i++) {
 612                 list_for_each_entry_safe(subflow, tmp, &msk->conn_list, node) {
 613                         struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
 614                         int how = RCV_SHUTDOWN | SEND_SHUTDOWN;
 615                         u8 id = subflow->local_id;
 616
 617                         if (rm_type == MPTCP_MIB_RMADDR)
 618                                 id = subflow->remote_id;
 619
 620                         if (rm_list->ids[i] != id)
 621                                 continue;
 622
 623                         pr_debug(" -> %s rm_list_ids[%d]=%u local_id=%u remote_id=%u",
 624                                  rm_type == MPTCP_MIB_RMADDR ? "address" : "subflow",
 625                                  i, rm_list->ids[i], subflow->local_id, subflow->remote_id);
 626                         spin_unlock_bh(&msk->pm.lock);
 627                         mptcp_subflow_shutdown(sk, ssk, how);
 628                         mptcp_close_ssk(sk, ssk, subflow);
 629                         spin_lock_bh(&msk->pm.lock);
 630
 631                         if (rm_type == MPTCP_MIB_RMADDR) {
 632                                 msk->pm.add_addr_accepted--;
 633                                 WRITE_ONCE(msk->pm.accept_addr, true);
 634                         } else if (rm_type == MPTCP_MIB_RMSUBFLOW) {
 635                                 msk->pm.local_addr_used--;
 636                         }
 637                         msk->pm.subflows--;
 638                         __MPTCP_INC_STATS(sock_net(sk), rm_type);
 639                 }
 640         }
 641 }
 642
 643 static void mptcp_pm_nl_rm_addr_received(struct mptcp_sock *msk)
 644 {
 645         mptcp_pm_nl_rm_addr_or_subflow(msk, &msk->pm.rm_list_rx, MPTCP_MIB_RMADDR);
 646 }
 647
 648 void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk,
 649                                      const struct mptcp_rm_list *rm_list)
 650 {
 651         mptcp_pm_nl_rm_addr_or_subflow(msk, rm_list, MPTCP_MIB_RMSUBFLOW);
 652 }
 653
 654 void mptcp_pm_nl_work(struct mptcp_sock *msk)
 655 {
 656         struct mptcp_pm_data *pm = &msk->pm;
 657
 658         msk_owned_by_me(msk);
 659
 660         spin_lock_bh(&msk->pm.lock);
 661
 662         pr_debug("msk=%p status=%x", msk, pm->status);
 663         if (pm->status & BIT(MPTCP_PM_ADD_ADDR_RECEIVED)) {
 664                 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_RECEIVED);
 665                 mptcp_pm_nl_add_addr_received(msk);
 666         }
 667         if (pm->status & BIT(MPTCP_PM_ADD_ADDR_SEND_ACK)) {
 668                 pm->status &= ~BIT(MPTCP_PM_ADD_ADDR_SEND_ACK);
 669                 mptcp_pm_nl_addr_send_ack(msk);
 670         }
 671         if (pm->status & BIT(MPTCP_PM_RM_ADDR_RECEIVED)) {
 672                 pm->status &= ~BIT(MPTCP_PM_RM_ADDR_RECEIVED);
 673                 mptcp_pm_nl_rm_addr_received(msk);
 674         }
 675         if (pm->status & BIT(MPTCP_PM_ESTABLISHED)) {
 676                 pm->status &= ~BIT(MPTCP_PM_ESTABLISHED);
 677                 mptcp_pm_nl_fully_established(msk);
 678         }
 679         if (pm->status & BIT(MPTCP_PM_SUBFLOW_ESTABLISHED)) {
 680                 pm->status &= ~BIT(MPTCP_PM_SUBFLOW_ESTABLISHED);
 681                 mptcp_pm_nl_subflow_established(msk);
 682         }
 683
 684         spin_unlock_bh(&msk->pm.lock);
 685 }
 686
 687 static bool address_use_port(struct mptcp_pm_addr_entry *entry)
 688 {
 689         return (entry->flags &
 690                 (MPTCP_PM_ADDR_FLAG_SIGNAL | MPTCP_PM_ADDR_FLAG_SUBFLOW)) ==
 691                 MPTCP_PM_ADDR_FLAG_SIGNAL;
 692 }
 693
 694 static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet,
 695                                              struct mptcp_pm_addr_entry *entry)
 696 {
 697         struct mptcp_pm_addr_entry *cur;
 698         unsigned int addr_max;
 699         int ret = -EINVAL;
 700
 701         spin_lock_bh(&pernet->lock);
 702         /* to keep the code simple, don't do IDR-like allocation for address ID,
 703          * just bail when we exceed limits
 704          */
 705         if (pernet->next_id == MAX_ADDR_ID)
 706                 pernet->next_id = 1;
 707         if (pernet->addrs >= MPTCP_PM_ADDR_MAX)
 708                 goto out;
 709         if (test_bit(entry->addr.id, pernet->id_bitmap))
 710                 goto out;
 711
 712         /* do not insert duplicate address, differentiate on port only
 713          * singled addresses
 714          */
 715         list_for_each_entry(cur, &pernet->local_addr_list, list) {
 716                 if (addresses_equal(&cur->addr, &entry->addr,
 717                                     address_use_port(entry) &&
 718                                     address_use_port(cur)))
 719                         goto out;
 720         }
 721
 722         if (!entry->addr.id) {
 723 find_next:
 724                 entry->addr.id = find_next_zero_bit(pernet->id_bitmap,
 725                                                     MAX_ADDR_ID + 1,
 726                                                     pernet->next_id);
 727                 if ((!entry->addr.id || entry->addr.id > MAX_ADDR_ID) &&
 728                     pernet->next_id != 1) {
 729                         pernet->next_id = 1;
 730                         goto find_next;
 731                 }
 732         }
 733
 734         if (!entry->addr.id || entry->addr.id > MAX_ADDR_ID)
 735                 goto out;
 736
 737         __set_bit(entry->addr.id, pernet->id_bitmap);
 738         if (entry->addr.id > pernet->next_id)
 739                 pernet->next_id = entry->addr.id;
 740
 741         if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) {
 742                 addr_max = pernet->add_addr_signal_max;
 743                 WRITE_ONCE(pernet->add_addr_signal_max, addr_max + 1);
 744         }
 745         if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
 746                 addr_max = pernet->local_addr_max;
 747                 WRITE_ONCE(pernet->local_addr_max, addr_max + 1);
 748         }
 749
 750         pernet->addrs++;
 751         list_add_tail_rcu(&entry->list, &pernet->local_addr_list);
 752         ret = entry->addr.id;
 753
 754 out:
 755         spin_unlock_bh(&pernet->lock);
 756         return ret;
 757 }
 758
 759 static int mptcp_pm_nl_create_listen_socket(struct sock *sk,
 760                                             struct mptcp_pm_addr_entry *entry)
 761 {
 762         struct sockaddr_storage addr;
 763         struct mptcp_sock *msk;
 764         struct socket *ssock;
 765         int backlog = 1024;
 766         int err;
 767
 768         err = sock_create_kern(sock_net(sk), entry->addr.family,
 769                                SOCK_STREAM, IPPROTO_MPTCP, &entry->lsk);
 770         if (err)
 771                 return err;
 772
 773         msk = mptcp_sk(entry->lsk->sk);
 774         if (!msk) {
 775                 err = -EINVAL;
 776                 goto out;
 777         }
 778
 779         ssock = __mptcp_nmpc_socket(msk);
 780         if (!ssock) {
 781                 err = -EINVAL;
 782                 goto out;
 783         }
 784
 785         mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family);
 786         err = kernel_bind(ssock, (struct sockaddr *)&addr,
 787                           sizeof(struct sockaddr_in));
 788         if (err) {
 789                 pr_warn("kernel_bind error, err=%d", err);
 790                 goto out;
 791         }
 792
 793         err = kernel_listen(ssock, backlog);
 794         if (err) {
 795                 pr_warn("kernel_listen error, err=%d", err);
 796                 goto out;
 797         }
 798
 799         return 0;
 800
 801 out:
 802         sock_release(entry->lsk);
 803         return err;
 804 }
 805
 806 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc)
 807 {
 808         struct mptcp_pm_addr_entry *entry;
 809         struct mptcp_addr_info skc_local;
 810         struct mptcp_addr_info msk_local;
 811         struct pm_nl_pernet *pernet;
 812         int ret = -1;
 813
 814         if (WARN_ON_ONCE(!msk))
 815                 return -1;
 816
 817         /* The 0 ID mapping is defined by the first subflow, copied into the msk
 818          * addr
 819          */
 820         local_address((struct sock_common *)msk, &msk_local);
 821         local_address((struct sock_common *)skc, &skc_local);
 822         if (addresses_equal(&msk_local, &skc_local, false))
 823                 return 0;
 824
 825         if (address_zero(&skc_local))
 826                 return 0;
 827
 828         pernet = net_generic(sock_net((struct sock *)msk), pm_nl_pernet_id);
 829
 830         rcu_read_lock();
 831         list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
 832                 if (addresses_equal(&entry->addr, &skc_local, entry->addr.port)) {
 833                         ret = entry->addr.id;
 834                         break;
 835                 }
 836         }
 837         rcu_read_unlock();
 838         if (ret >= 0)
 839                 return ret;
 840
 841         /* address not found, add to local list */
 842         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
 843         if (!entry)
 844                 return -ENOMEM;
 845
 846         entry->addr = skc_local;
 847         entry->addr.id = 0;
 848         entry->addr.port = 0;
 849         entry->ifindex = 0;
 850         entry->flags = 0;
 851         entry->lsk = NULL;
 852         ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
 853         if (ret < 0)
 854                 kfree(entry);
 855
 856         return ret;
 857 }
 858
 859 void mptcp_pm_nl_data_init(struct mptcp_sock *msk)
 860 {
 861         struct mptcp_pm_data *pm = &msk->pm;
 862         bool subflows;
 863
 864         subflows = !!mptcp_pm_get_subflows_max(msk);
 865         WRITE_ONCE(pm->work_pending, (!!mptcp_pm_get_local_addr_max(msk) && subflows) ||
 866                    !!mptcp_pm_get_add_addr_signal_max(msk));
 867         WRITE_ONCE(pm->accept_addr, !!mptcp_pm_get_add_addr_accept_max(msk) && subflows);
 868         WRITE_ONCE(pm->accept_subflow, subflows);
 869 }
 870
 871 #define MPTCP_PM_CMD_GRP_OFFSET       0
 872 #define MPTCP_PM_EV_GRP_OFFSET        1
 873
 874 static const struct genl_multicast_group mptcp_pm_mcgrps[] = {
 875         [MPTCP_PM_CMD_GRP_OFFSET]       = { .name = MPTCP_PM_CMD_GRP_NAME, },
 876         [MPTCP_PM_EV_GRP_OFFSET]        = { .name = MPTCP_PM_EV_GRP_NAME,
 877                                             .flags = GENL_UNS_ADMIN_PERM,
 878                                           },
 879 };
 880
 881 static const struct nla_policy
 882 mptcp_pm_addr_policy[MPTCP_PM_ADDR_ATTR_MAX + 1] = {
 883         [MPTCP_PM_ADDR_ATTR_FAMILY]     = { .type       = NLA_U16,      },
 884         [MPTCP_PM_ADDR_ATTR_ID]         = { .type       = NLA_U8,       },
 885         [MPTCP_PM_ADDR_ATTR_ADDR4]      = { .type       = NLA_U32,      },
 886         [MPTCP_PM_ADDR_ATTR_ADDR6]      =
 887                 NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
 888         [MPTCP_PM_ADDR_ATTR_PORT]       = { .type       = NLA_U16       },
 889         [MPTCP_PM_ADDR_ATTR_FLAGS]      = { .type       = NLA_U32       },
 890         [MPTCP_PM_ADDR_ATTR_IF_IDX]     = { .type       = NLA_S32       },
 891 };
 892
 893 static const struct nla_policy mptcp_pm_policy[MPTCP_PM_ATTR_MAX + 1] = {
 894         [MPTCP_PM_ATTR_ADDR]            =
 895                                         NLA_POLICY_NESTED(mptcp_pm_addr_policy),
 896         [MPTCP_PM_ATTR_RCV_ADD_ADDRS]   = { .type       = NLA_U32,      },
 897         [MPTCP_PM_ATTR_SUBFLOWS]        = { .type       = NLA_U32,      },
 898 };
 899
 900 static int mptcp_pm_family_to_addr(int family)
 901 {
 902 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
 903         if (family == AF_INET6)
 904                 return MPTCP_PM_ADDR_ATTR_ADDR6;
 905 #endif
 906         return MPTCP_PM_ADDR_ATTR_ADDR4;
 907 }
 908
 909 static int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info,
 910                                bool require_family,
 911                                struct mptcp_pm_addr_entry *entry)
 912 {
 913         struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1];
 914         int err, addr_addr;
 915
 916         if (!attr) {
 917                 GENL_SET_ERR_MSG(info, "missing address info");
 918                 return -EINVAL;
 919         }
 920
 921         /* no validation needed - was already done via nested policy */
 922         err = nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr,
 923                                           mptcp_pm_addr_policy, info->extack);
 924         if (err)
 925                 return err;
 926
 927         memset(entry, 0, sizeof(*entry));
 928         if (!tb[MPTCP_PM_ADDR_ATTR_FAMILY]) {
 929                 if (!require_family)
 930                         goto skip_family;
 931
 932                 NL_SET_ERR_MSG_ATTR(info->extack, attr,
 933                                     "missing family");
 934                 return -EINVAL;
 935         }
 936
 937         entry->addr.family = nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_FAMILY]);
 938         if (entry->addr.family != AF_INET
 939 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
 940             && entry->addr.family != AF_INET6
 941 #endif
 942             ) {
 943                 NL_SET_ERR_MSG_ATTR(info->extack, attr,
 944                                     "unknown address family");
 945                 return -EINVAL;
 946         }
 947         addr_addr = mptcp_pm_family_to_addr(entry->addr.family);
 948         if (!tb[addr_addr]) {
 949                 NL_SET_ERR_MSG_ATTR(info->extack, attr,
 950                                     "missing address data");
 951                 return -EINVAL;
 952         }
 953
 954 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
 955         if (entry->addr.family == AF_INET6)
 956                 entry->addr.addr6 = nla_get_in6_addr(tb[addr_addr]);
 957         else
 958 #endif
 959                 entry->addr.addr.s_addr = nla_get_in_addr(tb[addr_addr]);
 960
 961 skip_family:
 962         if (tb[MPTCP_PM_ADDR_ATTR_IF_IDX]) {
 963                 u32 val = nla_get_s32(tb[MPTCP_PM_ADDR_ATTR_IF_IDX]);
 964
 965                 entry->ifindex = val;
 966         }
 967
 968         if (tb[MPTCP_PM_ADDR_ATTR_ID])
 969                 entry->addr.id = nla_get_u8(tb[MPTCP_PM_ADDR_ATTR_ID]);
 970
 971         if (tb[MPTCP_PM_ADDR_ATTR_FLAGS])
 972                 entry->flags = nla_get_u32(tb[MPTCP_PM_ADDR_ATTR_FLAGS]);
 973
 974         if (tb[MPTCP_PM_ADDR_ATTR_PORT])
 975                 entry->addr.port = htons(nla_get_u16(tb[MPTCP_PM_ADDR_ATTR_PORT]));
 976
 977         return 0;
 978 }
 979
 980 static struct pm_nl_pernet *genl_info_pm_nl(struct genl_info *info)
 981 {
 982         return net_generic(genl_info_net(info), pm_nl_pernet_id);
 983 }
 984
 985 static int mptcp_nl_add_subflow_or_signal_addr(struct net *net)
 986 {
 987         struct mptcp_sock *msk;
 988         long s_slot = 0, s_num = 0;
 989
 990         while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
 991                 struct sock *sk = (struct sock *)msk;
 992
 993                 if (!READ_ONCE(msk->fully_established))
 994                         goto next;
 995
 996                 lock_sock(sk);
 997                 spin_lock_bh(&msk->pm.lock);
 998                 mptcp_pm_create_subflow_or_signal_addr(msk);
 999                 spin_unlock_bh(&msk->pm.lock);
1000                 release_sock(sk);
1001
1002 next:
1003                 sock_put(sk);
1004                 cond_resched();
1005         }
1006
1007         return 0;
1008 }
1009
1010 static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info)
1011 {
1012         struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
1013         struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1014         struct mptcp_pm_addr_entry addr, *entry;
1015         int ret;
1016
1017         ret = mptcp_pm_parse_addr(attr, info, true, &addr);
1018         if (ret < 0)
1019                 return ret;
1020
1021         entry = kmalloc(sizeof(*entry), GFP_KERNEL);
1022         if (!entry) {
1023                 GENL_SET_ERR_MSG(info, "can't allocate addr");
1024                 return -ENOMEM;
1025         }
1026
1027         *entry = addr;
1028         if (entry->addr.port) {
1029                 ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry);
1030                 if (ret) {
1031                         GENL_SET_ERR_MSG(info, "create listen socket error");
1032                         kfree(entry);
1033                         return ret;
1034                 }
1035         }
1036         ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
1037         if (ret < 0) {
1038                 GENL_SET_ERR_MSG(info, "too many addresses or duplicate one");
1039                 if (entry->lsk)
1040                         sock_release(entry->lsk);
1041                 kfree(entry);
1042                 return ret;
1043         }
1044
1045         mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk));
1046
1047         return 0;
1048 }
1049
1050 static struct mptcp_pm_addr_entry *
1051 __lookup_addr_by_id(struct pm_nl_pernet *pernet, unsigned int id)
1052 {
1053         struct mptcp_pm_addr_entry *entry;
1054
1055         list_for_each_entry(entry, &pernet->local_addr_list, list) {
1056                 if (entry->addr.id == id)
1057                         return entry;
1058         }
1059         return NULL;
1060 }
1061
1062 static bool remove_anno_list_by_saddr(struct mptcp_sock *msk,
1063                                       struct mptcp_addr_info *addr)
1064 {
1065         struct mptcp_pm_add_entry *entry;
1066
1067         entry = mptcp_pm_del_add_timer(msk, addr);
1068         if (entry) {
1069                 list_del(&entry->list);
1070                 kfree(entry);
1071                 return true;
1072         }
1073
1074         return false;
1075 }
1076
1077 static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk,
1078                                       struct mptcp_addr_info *addr,
1079                                       bool force)
1080 {
1081         struct mptcp_rm_list list = { .nr = 0 };
1082         bool ret;
1083
1084         list.ids[list.nr++] = addr->id;
1085
1086         ret = remove_anno_list_by_saddr(msk, addr);
1087         if (ret || force) {
1088                 spin_lock_bh(&msk->pm.lock);
1089                 mptcp_pm_remove_addr(msk, &list);
1090                 spin_unlock_bh(&msk->pm.lock);
1091         }
1092         return ret;
1093 }
1094
1095 static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
1096                                                    struct mptcp_addr_info *addr)
1097 {
1098         struct mptcp_sock *msk;
1099         long s_slot = 0, s_num = 0;
1100         struct mptcp_rm_list list = { .nr = 0 };
1101
1102         pr_debug("remove_id=%d", addr->id);
1103
1104         list.ids[list.nr++] = addr->id;
1105
1106         while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
1107                 struct sock *sk = (struct sock *)msk;
1108                 bool remove_subflow;
1109
1110                 if (list_empty(&msk->conn_list)) {
1111                         mptcp_pm_remove_anno_addr(msk, addr, false);
1112                         goto next;
1113                 }
1114
1115                 lock_sock(sk);
1116                 remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr);
1117                 mptcp_pm_remove_anno_addr(msk, addr, remove_subflow);
1118                 if (remove_subflow)
1119                         mptcp_pm_remove_subflow(msk, &list);
1120                 release_sock(sk);
1121
1122 next:
1123                 sock_put(sk);
1124                 cond_resched();
1125         }
1126
1127         return 0;
1128 }
1129
1130 struct addr_entry_release_work {
1131         struct rcu_work rwork;
1132         struct mptcp_pm_addr_entry *entry;
1133 };
1134
1135 static void mptcp_pm_release_addr_entry(struct work_struct *work)
1136 {
1137         struct addr_entry_release_work *w;
1138         struct mptcp_pm_addr_entry *entry;
1139
1140         w = container_of(to_rcu_work(work), struct addr_entry_release_work, rwork);
1141         entry = w->entry;
1142         if (entry) {
1143                 if (entry->lsk)
1144                         sock_release(entry->lsk);
1145                 kfree(entry);
1146         }
1147         kfree(w);
1148 }
1149
1150 static void mptcp_pm_free_addr_entry(struct mptcp_pm_addr_entry *entry)
1151 {
1152         struct addr_entry_release_work *w;
1153
1154         w = kmalloc(sizeof(*w), GFP_ATOMIC);
1155         if (w) {
1156                 INIT_RCU_WORK(&w->rwork, mptcp_pm_release_addr_entry);
1157                 w->entry = entry;
1158                 queue_rcu_work(system_wq, &w->rwork);
1159         }
1160 }
1161
1162 static int mptcp_nl_remove_id_zero_address(struct net *net,
1163                                            struct mptcp_addr_info *addr)
1164 {
1165         struct mptcp_rm_list list = { .nr = 0 };
1166         long s_slot = 0, s_num = 0;
1167         struct mptcp_sock *msk;
1168
1169         list.ids[list.nr++] = 0;
1170
1171         while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
1172                 struct sock *sk = (struct sock *)msk;
1173                 struct mptcp_addr_info msk_local;
1174
1175                 if (list_empty(&msk->conn_list))
1176                         goto next;
1177
1178                 local_address((struct sock_common *)msk, &msk_local);
1179                 if (!addresses_equal(&msk_local, addr, addr->port))
1180                         goto next;
1181
1182                 lock_sock(sk);
1183                 spin_lock_bh(&msk->pm.lock);
1184                 mptcp_pm_remove_addr(msk, &list);
1185                 mptcp_pm_nl_rm_subflow_received(msk, &list);
1186                 spin_unlock_bh(&msk->pm.lock);
1187                 release_sock(sk);
1188
1189 next:
1190                 sock_put(sk);
1191                 cond_resched();
1192         }
1193
1194         return 0;
1195 }
1196
1197 static int mptcp_nl_cmd_del_addr(struct sk_buff *skb, struct genl_info *info)
1198 {
1199         struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
1200         struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1201         struct mptcp_pm_addr_entry addr, *entry;
1202         unsigned int addr_max;
1203         int ret;
1204
1205         ret = mptcp_pm_parse_addr(attr, info, false, &addr);
1206         if (ret < 0)
1207                 return ret;
1208
1209         /* the zero id address is special: the first address used by the msk
1210          * always gets such an id, so different subflows can have different zero
1211          * id addresses. Additionally zero id is not accounted for in id_bitmap.
1212          * Let's use an 'mptcp_rm_list' instead of the common remove code.
1213          */
1214         if (addr.addr.id == 0)
1215                 return mptcp_nl_remove_id_zero_address(sock_net(skb->sk), &addr.addr);
1216
1217         spin_lock_bh(&pernet->lock);
1218         entry = __lookup_addr_by_id(pernet, addr.addr.id);
1219         if (!entry) {
1220                 GENL_SET_ERR_MSG(info, "address not found");
1221                 spin_unlock_bh(&pernet->lock);
1222                 return -EINVAL;
1223         }
1224         if (entry->flags & MPTCP_PM_ADDR_FLAG_SIGNAL) {
1225                 addr_max = pernet->add_addr_signal_max;
1226                 WRITE_ONCE(pernet->add_addr_signal_max, addr_max - 1);
1227         }
1228         if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) {
1229                 addr_max = pernet->local_addr_max;
1230                 WRITE_ONCE(pernet->local_addr_max, addr_max - 1);
1231         }
1232
1233         pernet->addrs--;
1234         list_del_rcu(&entry->list);
1235         __clear_bit(entry->addr.id, pernet->id_bitmap);
1236         spin_unlock_bh(&pernet->lock);
1237
1238         mptcp_nl_remove_subflow_and_signal_addr(sock_net(skb->sk), &entry->addr);
1239         mptcp_pm_free_addr_entry(entry);
1240
1241         return ret;
1242 }
1243
1244 static void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
1245                                                struct list_head *rm_list)
1246 {
1247         struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 };
1248         struct mptcp_pm_addr_entry *entry;
1249
1250         list_for_each_entry(entry, rm_list, list) {
1251                 if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) &&
1252                     alist.nr < MPTCP_RM_IDS_MAX &&
1253                     slist.nr < MPTCP_RM_IDS_MAX) {
1254                         alist.ids[alist.nr++] = entry->addr.id;
1255                         slist.ids[slist.nr++] = entry->addr.id;
1256                 } else if (remove_anno_list_by_saddr(msk, &entry->addr) &&
1257                          alist.nr < MPTCP_RM_IDS_MAX) {
1258                         alist.ids[alist.nr++] = entry->addr.id;
1259                 }
1260         }
1261
1262         if (alist.nr) {
1263                 spin_lock_bh(&msk->pm.lock);
1264                 mptcp_pm_remove_addr(msk, &alist);
1265                 spin_unlock_bh(&msk->pm.lock);
1266         }
1267         if (slist.nr)
1268                 mptcp_pm_remove_subflow(msk, &slist);
1269 }
1270
1271 static void mptcp_nl_remove_addrs_list(struct net *net,
1272                                        struct list_head *rm_list)
1273 {
1274         long s_slot = 0, s_num = 0;
1275         struct mptcp_sock *msk;
1276
1277         if (list_empty(rm_list))
1278                 return;
1279
1280         while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
1281                 struct sock *sk = (struct sock *)msk;
1282
1283                 lock_sock(sk);
1284                 mptcp_pm_remove_addrs_and_subflows(msk, rm_list);
1285                 release_sock(sk);
1286
1287                 sock_put(sk);
1288                 cond_resched();
1289         }
1290 }
1291
1292 static void __flush_addrs(struct list_head *list)
1293 {
1294         while (!list_empty(list)) {
1295                 struct mptcp_pm_addr_entry *cur;
1296
1297                 cur = list_entry(list->next,
1298                                  struct mptcp_pm_addr_entry, list);
1299                 list_del_rcu(&cur->list);
1300                 mptcp_pm_free_addr_entry(cur);
1301         }
1302 }
1303
1304 static void __reset_counters(struct pm_nl_pernet *pernet)
1305 {
1306         WRITE_ONCE(pernet->add_addr_signal_max, 0);
1307         WRITE_ONCE(pernet->add_addr_accept_max, 0);
1308         WRITE_ONCE(pernet->local_addr_max, 0);
1309         pernet->addrs = 0;
1310 }
1311
1312 static int mptcp_nl_cmd_flush_addrs(struct sk_buff *skb, struct genl_info *info)
1313 {
1314         struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1315         LIST_HEAD(free_list);
1316
1317         spin_lock_bh(&pernet->lock);
1318         list_splice_init(&pernet->local_addr_list, &free_list);
1319         __reset_counters(pernet);
1320         pernet->next_id = 1;
1321         bitmap_zero(pernet->id_bitmap, MAX_ADDR_ID + 1);
1322         spin_unlock_bh(&pernet->lock);
1323         mptcp_nl_remove_addrs_list(sock_net(skb->sk), &free_list);
1324         __flush_addrs(&free_list);
1325         return 0;
1326 }
1327
1328 static int mptcp_nl_fill_addr(struct sk_buff *skb,
1329                               struct mptcp_pm_addr_entry *entry)
1330 {
1331         struct mptcp_addr_info *addr = &entry->addr;
1332         struct nlattr *attr;
1333
1334         attr = nla_nest_start(skb, MPTCP_PM_ATTR_ADDR);
1335         if (!attr)
1336                 return -EMSGSIZE;
1337
1338         if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_FAMILY, addr->family))
1339                 goto nla_put_failure;
1340         if (nla_put_u16(skb, MPTCP_PM_ADDR_ATTR_PORT, ntohs(addr->port)))
1341                 goto nla_put_failure;
1342         if (nla_put_u8(skb, MPTCP_PM_ADDR_ATTR_ID, addr->id))
1343                 goto nla_put_failure;
1344         if (nla_put_u32(skb, MPTCP_PM_ADDR_ATTR_FLAGS, entry->flags))
1345                 goto nla_put_failure;
1346         if (entry->ifindex &&
1347             nla_put_s32(skb, MPTCP_PM_ADDR_ATTR_IF_IDX, entry->ifindex))
1348                 goto nla_put_failure;
1349
1350         if (addr->family == AF_INET &&
1351             nla_put_in_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR4,
1352                             addr->addr.s_addr))
1353                 goto nla_put_failure;
1354 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
1355         else if (addr->family == AF_INET6 &&
1356                  nla_put_in6_addr(skb, MPTCP_PM_ADDR_ATTR_ADDR6, &addr->addr6))
1357                 goto nla_put_failure;
1358 #endif
1359         nla_nest_end(skb, attr);
1360         return 0;
1361
1362 nla_put_failure:
1363         nla_nest_cancel(skb, attr);
1364         return -EMSGSIZE;
1365 }
1366
1367 static int mptcp_nl_cmd_get_addr(struct sk_buff *skb, struct genl_info *info)
1368 {
1369         struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
1370         struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1371         struct mptcp_pm_addr_entry addr, *entry;
1372         struct sk_buff *msg;
1373         void *reply;
1374         int ret;
1375
1376         ret = mptcp_pm_parse_addr(attr, info, false, &addr);
1377         if (ret < 0)
1378                 return ret;
1379
1380         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1381         if (!msg)
1382                 return -ENOMEM;
1383
1384         reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0,
1385                                   info->genlhdr->cmd);
1386         if (!reply) {
1387                 GENL_SET_ERR_MSG(info, "not enough space in Netlink message");
1388                 ret = -EMSGSIZE;
1389                 goto fail;
1390         }
1391
1392         spin_lock_bh(&pernet->lock);
1393         entry = __lookup_addr_by_id(pernet, addr.addr.id);
1394         if (!entry) {
1395                 GENL_SET_ERR_MSG(info, "address not found");
1396                 ret = -EINVAL;
1397                 goto unlock_fail;
1398         }
1399
1400         ret = mptcp_nl_fill_addr(msg, entry);
1401         if (ret)
1402                 goto unlock_fail;
1403
1404         genlmsg_end(msg, reply);
1405         ret = genlmsg_reply(msg, info);
1406         spin_unlock_bh(&pernet->lock);
1407         return ret;
1408
1409 unlock_fail:
1410         spin_unlock_bh(&pernet->lock);
1411
1412 fail:
1413         nlmsg_free(msg);
1414         return ret;
1415 }
1416
1417 static int mptcp_nl_cmd_dump_addrs(struct sk_buff *msg,
1418                                    struct netlink_callback *cb)
1419 {
1420         struct net *net = sock_net(msg->sk);
1421         struct mptcp_pm_addr_entry *entry;
1422         struct pm_nl_pernet *pernet;
1423         int id = cb->args[0];
1424         void *hdr;
1425         int i;
1426
1427         pernet = net_generic(net, pm_nl_pernet_id);
1428
1429         spin_lock_bh(&pernet->lock);
1430         for (i = id; i < MAX_ADDR_ID + 1; i++) {
1431                 if (test_bit(i, pernet->id_bitmap)) {
1432                         entry = __lookup_addr_by_id(pernet, i);
1433                         if (!entry)
1434                                 break;
1435
1436                         if (entry->addr.id <= id)
1437                                 continue;
1438
1439                         hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid,
1440                                           cb->nlh->nlmsg_seq, &mptcp_genl_family,
1441                                           NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR);
1442                         if (!hdr)
1443                                 break;
1444
1445                         if (mptcp_nl_fill_addr(msg, entry) < 0) {
1446                                 genlmsg_cancel(msg, hdr);
1447                                 break;
1448                         }
1449
1450                         id = entry->addr.id;
1451                         genlmsg_end(msg, hdr);
1452                 }
1453         }
1454         spin_unlock_bh(&pernet->lock);
1455
1456         cb->args[0] = id;
1457         return msg->len;
1458 }
1459
1460 static int parse_limit(struct genl_info *info, int id, unsigned int *limit)
1461 {
1462         struct nlattr *attr = info->attrs[id];
1463
1464         if (!attr)
1465                 return 0;
1466
1467         *limit = nla_get_u32(attr);
1468         if (*limit > MPTCP_PM_ADDR_MAX) {
1469                 GENL_SET_ERR_MSG(info, "limit greater than maximum");
1470                 return -EINVAL;
1471         }
1472         return 0;
1473 }
1474
1475 static int
1476 mptcp_nl_cmd_set_limits(struct sk_buff *skb, struct genl_info *info)
1477 {
1478         struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1479         unsigned int rcv_addrs, subflows;
1480         int ret;
1481
1482         spin_lock_bh(&pernet->lock);
1483         rcv_addrs = pernet->add_addr_accept_max;
1484         ret = parse_limit(info, MPTCP_PM_ATTR_RCV_ADD_ADDRS, &rcv_addrs);
1485         if (ret)
1486                 goto unlock;
1487
1488         subflows = pernet->subflows_max;
1489         ret = parse_limit(info, MPTCP_PM_ATTR_SUBFLOWS, &subflows);
1490         if (ret)
1491                 goto unlock;
1492
1493         WRITE_ONCE(pernet->add_addr_accept_max, rcv_addrs);
1494         WRITE_ONCE(pernet->subflows_max, subflows);
1495
1496 unlock:
1497         spin_unlock_bh(&pernet->lock);
1498         return ret;
1499 }
1500
1501 static int
1502 mptcp_nl_cmd_get_limits(struct sk_buff *skb, struct genl_info *info)
1503 {
1504         struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1505         struct sk_buff *msg;
1506         void *reply;
1507
1508         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1509         if (!msg)
1510                 return -ENOMEM;
1511
1512         reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0,
1513                                   MPTCP_PM_CMD_GET_LIMITS);
1514         if (!reply)
1515                 goto fail;
1516
1517         if (nla_put_u32(msg, MPTCP_PM_ATTR_RCV_ADD_ADDRS,
1518                         READ_ONCE(pernet->add_addr_accept_max)))
1519                 goto fail;
1520
1521         if (nla_put_u32(msg, MPTCP_PM_ATTR_SUBFLOWS,
1522                         READ_ONCE(pernet->subflows_max)))
1523                 goto fail;
1524
1525         genlmsg_end(msg, reply);
1526         return genlmsg_reply(msg, info);
1527
1528 fail:
1529         GENL_SET_ERR_MSG(info, "not enough space in Netlink message");
1530         nlmsg_free(msg);
1531         return -EMSGSIZE;
1532 }
1533
1534 static int mptcp_nl_addr_backup(struct net *net,
1535                                 struct mptcp_addr_info *addr,
1536                                 u8 bkup)
1537 {
1538         long s_slot = 0, s_num = 0;
1539         struct mptcp_sock *msk;
1540         int ret = -EINVAL;
1541
1542         while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
1543                 struct sock *sk = (struct sock *)msk;
1544
1545                 if (list_empty(&msk->conn_list))
1546                         goto next;
1547
1548                 lock_sock(sk);
1549                 spin_lock_bh(&msk->pm.lock);
1550                 ret = mptcp_pm_nl_mp_prio_send_ack(msk, addr, bkup);
1551                 spin_unlock_bh(&msk->pm.lock);
1552                 release_sock(sk);
1553
1554 next:
1555                 sock_put(sk);
1556                 cond_resched();
1557         }
1558
1559         return ret;
1560 }
1561
1562 static int mptcp_nl_cmd_set_flags(struct sk_buff *skb, struct genl_info *info)
1563 {
1564         struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];
1565         struct pm_nl_pernet *pernet = genl_info_pm_nl(info);
1566         struct mptcp_pm_addr_entry addr, *entry;
1567         struct net *net = sock_net(skb->sk);
1568         u8 bkup = 0;
1569         int ret;
1570
1571         ret = mptcp_pm_parse_addr(attr, info, true, &addr);
1572         if (ret < 0)
1573                 return ret;
1574
1575         if (addr.flags & MPTCP_PM_ADDR_FLAG_BACKUP)
1576                 bkup = 1;
1577
1578         list_for_each_entry(entry, &pernet->local_addr_list, list) {
1579                 if (addresses_equal(&entry->addr, &addr.addr, true)) {
1580                         ret = mptcp_nl_addr_backup(net, &entry->addr, bkup);
1581                         if (ret)
1582                                 return ret;
1583
1584                         if (bkup)
1585                                 entry->flags |= MPTCP_PM_ADDR_FLAG_BACKUP;
1586                         else
1587                                 entry->flags &= ~MPTCP_PM_ADDR_FLAG_BACKUP;
1588                 }
1589         }
1590
1591         return 0;
1592 }
1593
1594 static void mptcp_nl_mcast_send(struct net *net, struct sk_buff *nlskb, gfp_t gfp)
1595 {
1596         genlmsg_multicast_netns(&mptcp_genl_family, net,
1597                                 nlskb, 0, MPTCP_PM_EV_GRP_OFFSET, gfp);
1598 }
1599
1600 static int mptcp_event_add_subflow(struct sk_buff *skb, const struct sock *ssk)
1601 {
1602         const struct inet_sock *issk = inet_sk(ssk);
1603         const struct mptcp_subflow_context *sf;
1604
1605         if (nla_put_u16(skb, MPTCP_ATTR_FAMILY, ssk->sk_family))
1606                 return -EMSGSIZE;
1607
1608         switch (ssk->sk_family) {
1609         case AF_INET:
1610                 if (nla_put_in_addr(skb, MPTCP_ATTR_SADDR4, issk->inet_saddr))
1611                         return -EMSGSIZE;
1612                 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, issk->inet_daddr))
1613                         return -EMSGSIZE;
1614                 break;
1615 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
1616         case AF_INET6: {
1617                 const struct ipv6_pinfo *np = inet6_sk(ssk);
1618
1619                 if (nla_put_in6_addr(skb, MPTCP_ATTR_SADDR6, &np->saddr))
1620                         return -EMSGSIZE;
1621                 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &ssk->sk_v6_daddr))
1622                         return -EMSGSIZE;
1623                 break;
1624         }
1625 #endif
1626         default:
1627                 WARN_ON_ONCE(1);
1628                 return -EMSGSIZE;
1629         }
1630
1631         if (nla_put_be16(skb, MPTCP_ATTR_SPORT, issk->inet_sport))
1632                 return -EMSGSIZE;
1633         if (nla_put_be16(skb, MPTCP_ATTR_DPORT, issk->inet_dport))
1634                 return -EMSGSIZE;
1635
1636         sf = mptcp_subflow_ctx(ssk);
1637         if (WARN_ON_ONCE(!sf))
1638                 return -EINVAL;
1639
1640         if (nla_put_u8(skb, MPTCP_ATTR_LOC_ID, sf->local_id))
1641                 return -EMSGSIZE;
1642
1643         if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, sf->remote_id))
1644                 return -EMSGSIZE;
1645
1646         return 0;
1647 }
1648
1649 static int mptcp_event_put_token_and_ssk(struct sk_buff *skb,
1650                                          const struct mptcp_sock *msk,
1651                                          const struct sock *ssk)
1652 {
1653         const struct sock *sk = (const struct sock *)msk;
1654         const struct mptcp_subflow_context *sf;
1655         u8 sk_err;
1656
1657         if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token))
1658                 return -EMSGSIZE;
1659
1660         if (mptcp_event_add_subflow(skb, ssk))
1661                 return -EMSGSIZE;
1662
1663         sf = mptcp_subflow_ctx(ssk);
1664         if (WARN_ON_ONCE(!sf))
1665                 return -EINVAL;
1666
1667         if (nla_put_u8(skb, MPTCP_ATTR_BACKUP, sf->backup))
1668                 return -EMSGSIZE;
1669
1670         if (ssk->sk_bound_dev_if &&
1671             nla_put_s32(skb, MPTCP_ATTR_IF_IDX, ssk->sk_bound_dev_if))
1672                 return -EMSGSIZE;
1673
1674         sk_err = ssk->sk_err;
1675         if (sk_err && sk->sk_state == TCP_ESTABLISHED &&
1676             nla_put_u8(skb, MPTCP_ATTR_ERROR, sk_err))
1677                 return -EMSGSIZE;
1678
1679         return 0;
1680 }
1681
1682 static int mptcp_event_sub_established(struct sk_buff *skb,
1683                                        const struct mptcp_sock *msk,
1684                                        const struct sock *ssk)
1685 {
1686         return mptcp_event_put_token_and_ssk(skb, msk, ssk);
1687 }
1688
1689 static int mptcp_event_sub_closed(struct sk_buff *skb,
1690                                   const struct mptcp_sock *msk,
1691                                   const struct sock *ssk)
1692 {
1693         const struct mptcp_subflow_context *sf;
1694
1695         if (mptcp_event_put_token_and_ssk(skb, msk, ssk))
1696                 return -EMSGSIZE;
1697
1698         sf = mptcp_subflow_ctx(ssk);
1699         if (!sf->reset_seen)
1700                 return 0;
1701
1702         if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason))
1703                 return -EMSGSIZE;
1704
1705         if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient))
1706                 return -EMSGSIZE;
1707
1708         return 0;
1709 }
1710
1711 static int mptcp_event_created(struct sk_buff *skb,
1712                                const struct mptcp_sock *msk,
1713                                const struct sock *ssk)
1714 {
1715         int err = nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token);
1716
1717         if (err)
1718                 return err;
1719
1720         return mptcp_event_add_subflow(skb, ssk);
1721 }
1722
1723 void mptcp_event_addr_removed(const struct mptcp_sock *msk, uint8_t id)
1724 {
1725         struct net *net = sock_net((const struct sock *)msk);
1726         struct nlmsghdr *nlh;
1727         struct sk_buff *skb;
1728
1729         if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
1730                 return;
1731
1732         skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
1733         if (!skb)
1734                 return;
1735
1736         nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, MPTCP_EVENT_REMOVED);
1737         if (!nlh)
1738                 goto nla_put_failure;
1739
1740         if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token))
1741                 goto nla_put_failure;
1742
1743         if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, id))
1744                 goto nla_put_failure;
1745
1746         genlmsg_end(skb, nlh);
1747         mptcp_nl_mcast_send(net, skb, GFP_ATOMIC);
1748         return;
1749
1750 nla_put_failure:
1751         kfree_skb(skb);
1752 }
1753
1754 void mptcp_event_addr_announced(const struct mptcp_sock *msk,
1755                                 const struct mptcp_addr_info *info)
1756 {
1757         struct net *net = sock_net((const struct sock *)msk);
1758         struct nlmsghdr *nlh;
1759         struct sk_buff *skb;
1760
1761         if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
1762                 return;
1763
1764         skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
1765         if (!skb)
1766                 return;
1767
1768         nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0,
1769                           MPTCP_EVENT_ANNOUNCED);
1770         if (!nlh)
1771                 goto nla_put_failure;
1772
1773         if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token))
1774                 goto nla_put_failure;
1775
1776         if (nla_put_u8(skb, MPTCP_ATTR_REM_ID, info->id))
1777                 goto nla_put_failure;
1778
1779         if (nla_put_be16(skb, MPTCP_ATTR_DPORT, info->port))
1780                 goto nla_put_failure;
1781
1782         switch (info->family) {
1783         case AF_INET:
1784                 if (nla_put_in_addr(skb, MPTCP_ATTR_DADDR4, info->addr.s_addr))
1785                         goto nla_put_failure;
1786                 break;
1787 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
1788         case AF_INET6:
1789                 if (nla_put_in6_addr(skb, MPTCP_ATTR_DADDR6, &info->addr6))
1790                         goto nla_put_failure;
1791                 break;
1792 #endif
1793         default:
1794                 WARN_ON_ONCE(1);
1795                 goto nla_put_failure;
1796         }
1797
1798         genlmsg_end(skb, nlh);
1799         mptcp_nl_mcast_send(net, skb, GFP_ATOMIC);
1800         return;
1801
1802 nla_put_failure:
1803         kfree_skb(skb);
1804 }
1805
1806 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
1807                  const struct sock *ssk, gfp_t gfp)
1808 {
1809         struct net *net = sock_net((const struct sock *)msk);
1810         struct nlmsghdr *nlh;
1811         struct sk_buff *skb;
1812
1813         if (!genl_has_listeners(&mptcp_genl_family, net, MPTCP_PM_EV_GRP_OFFSET))
1814                 return;
1815
1816         skb = nlmsg_new(NLMSG_DEFAULT_SIZE, gfp);
1817         if (!skb)
1818                 return;
1819
1820         nlh = genlmsg_put(skb, 0, 0, &mptcp_genl_family, 0, type);
1821         if (!nlh)
1822                 goto nla_put_failure;
1823
1824         switch (type) {
1825         case MPTCP_EVENT_UNSPEC:
1826                 WARN_ON_ONCE(1);
1827                 break;
1828         case MPTCP_EVENT_CREATED:
1829         case MPTCP_EVENT_ESTABLISHED:
1830                 if (mptcp_event_created(skb, msk, ssk) < 0)
1831                         goto nla_put_failure;
1832                 break;
1833         case MPTCP_EVENT_CLOSED:
1834                 if (nla_put_u32(skb, MPTCP_ATTR_TOKEN, msk->token) < 0)
1835                         goto nla_put_failure;
1836                 break;
1837         case MPTCP_EVENT_ANNOUNCED:
1838         case MPTCP_EVENT_REMOVED:
1839                 /* call mptcp_event_addr_announced()/removed instead */
1840                 WARN_ON_ONCE(1);
1841                 break;
1842         case MPTCP_EVENT_SUB_ESTABLISHED:
1843         case MPTCP_EVENT_SUB_PRIORITY:
1844                 if (mptcp_event_sub_established(skb, msk, ssk) < 0)
1845                         goto nla_put_failure;
1846                 break;
1847         case MPTCP_EVENT_SUB_CLOSED:
1848                 if (mptcp_event_sub_closed(skb, msk, ssk) < 0)
1849                         goto nla_put_failure;
1850                 break;
1851         }
1852
1853         genlmsg_end(skb, nlh);
1854         mptcp_nl_mcast_send(net, skb, gfp);
1855         return;
1856
1857 nla_put_failure:
1858         kfree_skb(skb);
1859 }
1860
1861 static const struct genl_small_ops mptcp_pm_ops[] = {
1862         {
1863                 .cmd    = MPTCP_PM_CMD_ADD_ADDR,
1864                 .doit   = mptcp_nl_cmd_add_addr,
1865                 .flags  = GENL_ADMIN_PERM,
1866         },
1867         {
1868                 .cmd    = MPTCP_PM_CMD_DEL_ADDR,
1869                 .doit   = mptcp_nl_cmd_del_addr,
1870                 .flags  = GENL_ADMIN_PERM,
1871         },
1872         {
1873                 .cmd    = MPTCP_PM_CMD_FLUSH_ADDRS,
1874                 .doit   = mptcp_nl_cmd_flush_addrs,
1875                 .flags  = GENL_ADMIN_PERM,
1876         },
1877         {
1878                 .cmd    = MPTCP_PM_CMD_GET_ADDR,
1879                 .doit   = mptcp_nl_cmd_get_addr,
1880                 .dumpit   = mptcp_nl_cmd_dump_addrs,
1881         },
1882         {
1883                 .cmd    = MPTCP_PM_CMD_SET_LIMITS,
1884                 .doit   = mptcp_nl_cmd_set_limits,
1885                 .flags  = GENL_ADMIN_PERM,
1886         },
1887         {
1888                 .cmd    = MPTCP_PM_CMD_GET_LIMITS,
1889                 .doit   = mptcp_nl_cmd_get_limits,
1890         },
1891         {
1892                 .cmd    = MPTCP_PM_CMD_SET_FLAGS,
1893                 .doit   = mptcp_nl_cmd_set_flags,
1894                 .flags  = GENL_ADMIN_PERM,
1895         },
1896 };
1897
1898 static struct genl_family mptcp_genl_family __ro_after_init = {
1899         .name           = MPTCP_PM_NAME,
1900         .version        = MPTCP_PM_VER,
1901         .maxattr        = MPTCP_PM_ATTR_MAX,
1902         .policy         = mptcp_pm_policy,
1903         .netnsok        = true,
1904         .module         = THIS_MODULE,
1905         .small_ops      = mptcp_pm_ops,
1906         .n_small_ops    = ARRAY_SIZE(mptcp_pm_ops),
1907         .mcgrps         = mptcp_pm_mcgrps,
1908         .n_mcgrps       = ARRAY_SIZE(mptcp_pm_mcgrps),
1909 };
1910
1911 static int __net_init pm_nl_init_net(struct net *net)
1912 {
1913         struct pm_nl_pernet *pernet = net_generic(net, pm_nl_pernet_id);
1914
1915         INIT_LIST_HEAD_RCU(&pernet->local_addr_list);
1916         __reset_counters(pernet);
1917         pernet->next_id = 1;
1918         bitmap_zero(pernet->id_bitmap, MAX_ADDR_ID + 1);
1919         spin_lock_init(&pernet->lock);
1920         return 0;
1921 }
1922
1923 static void __net_exit pm_nl_exit_net(struct list_head *net_list)
1924 {
1925         struct net *net;
1926
1927         list_for_each_entry(net, net_list, exit_list) {
1928                 struct pm_nl_pernet *pernet = net_generic(net, pm_nl_pernet_id);
1929
1930                 /* net is removed from namespace list, can't race with
1931                  * other modifiers
1932                  */
1933                 __flush_addrs(&pernet->local_addr_list);
1934         }
1935 }
1936
1937 static struct pernet_operations mptcp_pm_pernet_ops = {
1938         .init = pm_nl_init_net,
1939         .exit_batch = pm_nl_exit_net,
1940         .id = &pm_nl_pernet_id,
1941         .size = sizeof(struct pm_nl_pernet),
1942 };
1943
1944 void __init mptcp_pm_nl_init(void)
1945 {
1946         if (register_pernet_subsys(&mptcp_pm_pernet_ops) < 0)
1947                 panic("Failed to register MPTCP PM pernet subsystem.\n");
1948
1949         if (genl_register_family(&mptcp_genl_family))
1950                 panic("Failed to register MPTCP PM netlink family\n");
1951 }