net/vmw_vsock/af_vsock.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * VMware vSockets Driver
   4  *
   5  * Copyright (C) 2007-2013 VMware, Inc. All rights reserved.
   6  */
   7
   8 /* Implementation notes:
   9  *
  10  * - There are two kinds of sockets: those created by user action (such as
  11  * calling socket(2)) and those created by incoming connection request packets.
  12  *
  13  * - There are two "global" tables, one for bound sockets (sockets that have
  14  * specified an address that they are responsible for) and one for connected
  15  * sockets (sockets that have established a connection with another socket).
  16  * These tables are "global" in that all sockets on the system are placed
  17  * within them. - Note, though, that the bound table contains an extra entry
  18  * for a list of unbound sockets and SOCK_DGRAM sockets will always remain in
  19  * that list. The bound table is used solely for lookup of sockets when packets
  20  * are received and that's not necessary for SOCK_DGRAM sockets since we create
  21  * a datagram handle for each and need not perform a lookup.  Keeping SOCK_DGRAM
  22  * sockets out of the bound hash buckets will reduce the chance of collisions
  23  * when looking for SOCK_STREAM sockets and prevents us from having to check the
  24  * socket type in the hash table lookups.
  25  *
  26  * - Sockets created by user action will either be "client" sockets that
  27  * initiate a connection or "server" sockets that listen for connections; we do
  28  * not support simultaneous connects (two "client" sockets connecting).
  29  *
  30  * - "Server" sockets are referred to as listener sockets throughout this
  31  * implementation because they are in the TCP_LISTEN state.  When a
  32  * connection request is received (the second kind of socket mentioned above),
  33  * we create a new socket and refer to it as a pending socket.  These pending
  34  * sockets are placed on the pending connection list of the listener socket.
  35  * When future packets are received for the address the listener socket is
  36  * bound to, we check if the source of the packet is from one that has an
  37  * existing pending connection.  If it does, we process the packet for the
  38  * pending socket.  When that socket reaches the connected state, it is removed
  39  * from the listener socket's pending list and enqueued in the listener
  40  * socket's accept queue.  Callers of accept(2) will accept connected sockets
  41  * from the listener socket's accept queue.  If the socket cannot be accepted
  42  * for some reason then it is marked rejected.  Once the connection is
  43  * accepted, it is owned by the user process and the responsibility for cleanup
  44  * falls with that user process.
  45  *
  46  * - It is possible that these pending sockets will never reach the connected
  47  * state; in fact, we may never receive another packet after the connection
  48  * request.  Because of this, we must schedule a cleanup function to run in the
  49  * future, after some amount of time passes where a connection should have been
  50  * established.  This function ensures that the socket is off all lists so it
  51  * cannot be retrieved, then drops all references to the socket so it is cleaned
  52  * up (sock_put() -> sk_free() -> our sk_destruct implementation).  Note this
  53  * function will also cleanup rejected sockets, those that reach the connected
  54  * state but leave it before they have been accepted.
  55  *
  56  * - Lock ordering for pending or accept queue sockets is:
  57  *
  58  *     lock_sock(listener);
  59  *     lock_sock_nested(pending, SINGLE_DEPTH_NESTING);
  60  *
  61  * Using explicit nested locking keeps lockdep happy since normally only one
  62  * lock of a given class may be taken at a time.
  63  *
  64  * - Sockets created by user action will be cleaned up when the user process
  65  * calls close(2), causing our release implementation to be called. Our release
  66  * implementation will perform some cleanup then drop the last reference so our
  67  * sk_destruct implementation is invoked.  Our sk_destruct implementation will
  68  * perform additional cleanup that's common for both types of sockets.
  69  *
  70  * - A socket's reference count is what ensures that the structure won't be
  71  * freed.  Each entry in a list (such as the "global" bound and connected tables
  72  * and the listener socket's pending list and connected queue) ensures a
  73  * reference.  When we defer work until process context and pass a socket as our
  74  * argument, we must ensure the reference count is increased to ensure the
  75  * socket isn't freed before the function is run; the deferred function will
  76  * then drop the reference.
  77  *
  78  * - sk->sk_state uses the TCP state constants because they are widely used by
  79  * other address families and exposed to userspace tools like ss(8):
  80  *
  81  *   TCP_CLOSE - unconnected
  82  *   TCP_SYN_SENT - connecting
  83  *   TCP_ESTABLISHED - connected
  84  *   TCP_CLOSING - disconnecting
  85  *   TCP_LISTEN - listening
  86  */
  87
  88 #include <linux/types.h>
  89 #include <linux/bitops.h>
  90 #include <linux/cred.h>
  91 #include <linux/init.h>
  92 #include <linux/io.h>
  93 #include <linux/kernel.h>
  94 #include <linux/sched/signal.h>
  95 #include <linux/kmod.h>
  96 #include <linux/list.h>
  97 #include <linux/miscdevice.h>
  98 #include <linux/module.h>
  99 #include <linux/mutex.h>
 100 #include <linux/net.h>
 101 #include <linux/poll.h>
 102 #include <linux/random.h>
 103 #include <linux/skbuff.h>
 104 #include <linux/smp.h>
 105 #include <linux/socket.h>
 106 #include <linux/stddef.h>
 107 #include <linux/unistd.h>
 108 #include <linux/wait.h>
 109 #include <linux/workqueue.h>
 110 #include <net/sock.h>
 111 #include <net/af_vsock.h>
 112
 113 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr);
 114 static void vsock_sk_destruct(struct sock *sk);
 115 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
 116
 117 /* Protocol family. */
 118 static struct proto vsock_proto = {
 119         .name = "AF_VSOCK",
 120         .owner = THIS_MODULE,
 121         .obj_size = sizeof(struct vsock_sock),
 122 };
 123
 124 /* The default peer timeout indicates how long we will wait for a peer response
 125  * to a control message.
 126  */
 127 #define VSOCK_DEFAULT_CONNECT_TIMEOUT (2 * HZ)
 128
 129 #define VSOCK_DEFAULT_BUFFER_SIZE     (1024 * 256)
 130 #define VSOCK_DEFAULT_BUFFER_MAX_SIZE (1024 * 256)
 131 #define VSOCK_DEFAULT_BUFFER_MIN_SIZE 128
 132
 133 /* Transport used for host->guest communication */
 134 static const struct vsock_transport *transport_h2g;
 135 /* Transport used for guest->host communication */
 136 static const struct vsock_transport *transport_g2h;
 137 /* Transport used for DGRAM communication */
 138 static const struct vsock_transport *transport_dgram;
 139 /* Transport used for local communication */
 140 static const struct vsock_transport *transport_local;
 141 static DEFINE_MUTEX(vsock_register_mutex);
 142
 143 /**** UTILS ****/
 144
 145 /* Each bound VSocket is stored in the bind hash table and each connected
 146  * VSocket is stored in the connected hash table.
 147  *
 148  * Unbound sockets are all put on the same list attached to the end of the hash
 149  * table (vsock_unbound_sockets).  Bound sockets are added to the hash table in
 150  * the bucket that their local address hashes to (vsock_bound_sockets(addr)
 151  * represents the list that addr hashes to).
 152  *
 153  * Specifically, we initialize the vsock_bind_table array to a size of
 154  * VSOCK_HASH_SIZE + 1 so that vsock_bind_table[0] through
 155  * vsock_bind_table[VSOCK_HASH_SIZE - 1] are for bound sockets and
 156  * vsock_bind_table[VSOCK_HASH_SIZE] is for unbound sockets.  The hash function
 157  * mods with VSOCK_HASH_SIZE to ensure this.
 158  */
 159 #define MAX_PORT_RETRIES        24
 160
 161 #define VSOCK_HASH(addr)        ((addr)->svm_port % VSOCK_HASH_SIZE)
 162 #define vsock_bound_sockets(addr) (&vsock_bind_table[VSOCK_HASH(addr)])
 163 #define vsock_unbound_sockets     (&vsock_bind_table[VSOCK_HASH_SIZE])
 164
 165 /* XXX This can probably be implemented in a better way. */
 166 #define VSOCK_CONN_HASH(src, dst)                               \
 167         (((src)->svm_cid ^ (dst)->svm_port) % VSOCK_HASH_SIZE)
 168 #define vsock_connected_sockets(src, dst)               \
 169         (&vsock_connected_table[VSOCK_CONN_HASH(src, dst)])
 170 #define vsock_connected_sockets_vsk(vsk)                                \
 171         vsock_connected_sockets(&(vsk)->remote_addr, &(vsk)->local_addr)
 172
 173 struct list_head vsock_bind_table[VSOCK_HASH_SIZE + 1];
 174 EXPORT_SYMBOL_GPL(vsock_bind_table);
 175 struct list_head vsock_connected_table[VSOCK_HASH_SIZE];
 176 EXPORT_SYMBOL_GPL(vsock_connected_table);
 177 DEFINE_SPINLOCK(vsock_table_lock);
 178 EXPORT_SYMBOL_GPL(vsock_table_lock);
 179
 180 /* Autobind this socket to the local address if necessary. */
 181 static int vsock_auto_bind(struct vsock_sock *vsk)
 182 {
 183         struct sock *sk = sk_vsock(vsk);
 184         struct sockaddr_vm local_addr;
 185
 186         if (vsock_addr_bound(&vsk->local_addr))
 187                 return 0;
 188         vsock_addr_init(&local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 189         return __vsock_bind(sk, &local_addr);
 190 }
 191
 192 static void vsock_init_tables(void)
 193 {
 194         int i;
 195
 196         for (i = 0; i < ARRAY_SIZE(vsock_bind_table); i++)
 197                 INIT_LIST_HEAD(&vsock_bind_table[i]);
 198
 199         for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++)
 200                 INIT_LIST_HEAD(&vsock_connected_table[i]);
 201 }
 202
 203 static void __vsock_insert_bound(struct list_head *list,
 204                                  struct vsock_sock *vsk)
 205 {
 206         sock_hold(&vsk->sk);
 207         list_add(&vsk->bound_table, list);
 208 }
 209
 210 static void __vsock_insert_connected(struct list_head *list,
 211                                      struct vsock_sock *vsk)
 212 {
 213         sock_hold(&vsk->sk);
 214         list_add(&vsk->connected_table, list);
 215 }
 216
 217 static void __vsock_remove_bound(struct vsock_sock *vsk)
 218 {
 219         list_del_init(&vsk->bound_table);
 220         sock_put(&vsk->sk);
 221 }
 222
 223 static void __vsock_remove_connected(struct vsock_sock *vsk)
 224 {
 225         list_del_init(&vsk->connected_table);
 226         sock_put(&vsk->sk);
 227 }
 228
 229 static struct sock *__vsock_find_bound_socket(struct sockaddr_vm *addr)
 230 {
 231         struct vsock_sock *vsk;
 232
 233         list_for_each_entry(vsk, vsock_bound_sockets(addr), bound_table) {
 234                 if (vsock_addr_equals_addr(addr, &vsk->local_addr))
 235                         return sk_vsock(vsk);
 236
 237                 if (addr->svm_port == vsk->local_addr.svm_port &&
 238                     (vsk->local_addr.svm_cid == VMADDR_CID_ANY ||
 239                      addr->svm_cid == VMADDR_CID_ANY))
 240                         return sk_vsock(vsk);
 241         }
 242
 243         return NULL;
 244 }
 245
 246 static struct sock *__vsock_find_connected_socket(struct sockaddr_vm *src,
 247                                                   struct sockaddr_vm *dst)
 248 {
 249         struct vsock_sock *vsk;
 250
 251         list_for_each_entry(vsk, vsock_connected_sockets(src, dst),
 252                             connected_table) {
 253                 if (vsock_addr_equals_addr(src, &vsk->remote_addr) &&
 254                     dst->svm_port == vsk->local_addr.svm_port) {
 255                         return sk_vsock(vsk);
 256                 }
 257         }
 258
 259         return NULL;
 260 }
 261
 262 static void vsock_insert_unbound(struct vsock_sock *vsk)
 263 {
 264         spin_lock_bh(&vsock_table_lock);
 265         __vsock_insert_bound(vsock_unbound_sockets, vsk);
 266         spin_unlock_bh(&vsock_table_lock);
 267 }
 268
 269 void vsock_insert_connected(struct vsock_sock *vsk)
 270 {
 271         struct list_head *list = vsock_connected_sockets(
 272                 &vsk->remote_addr, &vsk->local_addr);
 273
 274         spin_lock_bh(&vsock_table_lock);
 275         __vsock_insert_connected(list, vsk);
 276         spin_unlock_bh(&vsock_table_lock);
 277 }
 278 EXPORT_SYMBOL_GPL(vsock_insert_connected);
 279
 280 void vsock_remove_bound(struct vsock_sock *vsk)
 281 {
 282         spin_lock_bh(&vsock_table_lock);
 283         if (__vsock_in_bound_table(vsk))
 284                 __vsock_remove_bound(vsk);
 285         spin_unlock_bh(&vsock_table_lock);
 286 }
 287 EXPORT_SYMBOL_GPL(vsock_remove_bound);
 288
 289 void vsock_remove_connected(struct vsock_sock *vsk)
 290 {
 291         spin_lock_bh(&vsock_table_lock);
 292         if (__vsock_in_connected_table(vsk))
 293                 __vsock_remove_connected(vsk);
 294         spin_unlock_bh(&vsock_table_lock);
 295 }
 296 EXPORT_SYMBOL_GPL(vsock_remove_connected);
 297
 298 struct sock *vsock_find_bound_socket(struct sockaddr_vm *addr)
 299 {
 300         struct sock *sk;
 301
 302         spin_lock_bh(&vsock_table_lock);
 303         sk = __vsock_find_bound_socket(addr);
 304         if (sk)
 305                 sock_hold(sk);
 306
 307         spin_unlock_bh(&vsock_table_lock);
 308
 309         return sk;
 310 }
 311 EXPORT_SYMBOL_GPL(vsock_find_bound_socket);
 312
 313 struct sock *vsock_find_connected_socket(struct sockaddr_vm *src,
 314                                          struct sockaddr_vm *dst)
 315 {
 316         struct sock *sk;
 317
 318         spin_lock_bh(&vsock_table_lock);
 319         sk = __vsock_find_connected_socket(src, dst);
 320         if (sk)
 321                 sock_hold(sk);
 322
 323         spin_unlock_bh(&vsock_table_lock);
 324
 325         return sk;
 326 }
 327 EXPORT_SYMBOL_GPL(vsock_find_connected_socket);
 328
 329 void vsock_remove_sock(struct vsock_sock *vsk)
 330 {
 331         vsock_remove_bound(vsk);
 332         vsock_remove_connected(vsk);
 333 }
 334 EXPORT_SYMBOL_GPL(vsock_remove_sock);
 335
 336 void vsock_for_each_connected_socket(void (*fn)(struct sock *sk))
 337 {
 338         int i;
 339
 340         spin_lock_bh(&vsock_table_lock);
 341
 342         for (i = 0; i < ARRAY_SIZE(vsock_connected_table); i++) {
 343                 struct vsock_sock *vsk;
 344                 list_for_each_entry(vsk, &vsock_connected_table[i],
 345                                     connected_table)
 346                         fn(sk_vsock(vsk));
 347         }
 348
 349         spin_unlock_bh(&vsock_table_lock);
 350 }
 351 EXPORT_SYMBOL_GPL(vsock_for_each_connected_socket);
 352
 353 void vsock_add_pending(struct sock *listener, struct sock *pending)
 354 {
 355         struct vsock_sock *vlistener;
 356         struct vsock_sock *vpending;
 357
 358         vlistener = vsock_sk(listener);
 359         vpending = vsock_sk(pending);
 360
 361         sock_hold(pending);
 362         sock_hold(listener);
 363         list_add_tail(&vpending->pending_links, &vlistener->pending_links);
 364 }
 365 EXPORT_SYMBOL_GPL(vsock_add_pending);
 366
 367 void vsock_remove_pending(struct sock *listener, struct sock *pending)
 368 {
 369         struct vsock_sock *vpending = vsock_sk(pending);
 370
 371         list_del_init(&vpending->pending_links);
 372         sock_put(listener);
 373         sock_put(pending);
 374 }
 375 EXPORT_SYMBOL_GPL(vsock_remove_pending);
 376
 377 void vsock_enqueue_accept(struct sock *listener, struct sock *connected)
 378 {
 379         struct vsock_sock *vlistener;
 380         struct vsock_sock *vconnected;
 381
 382         vlistener = vsock_sk(listener);
 383         vconnected = vsock_sk(connected);
 384
 385         sock_hold(connected);
 386         sock_hold(listener);
 387         list_add_tail(&vconnected->accept_queue, &vlistener->accept_queue);
 388 }
 389 EXPORT_SYMBOL_GPL(vsock_enqueue_accept);
 390
 391 static bool vsock_use_local_transport(unsigned int remote_cid)
 392 {
 393         if (!transport_local)
 394                 return false;
 395
 396         if (remote_cid == VMADDR_CID_LOCAL)
 397                 return true;
 398
 399         if (transport_g2h) {
 400                 return remote_cid == transport_g2h->get_local_cid();
 401         } else {
 402                 return remote_cid == VMADDR_CID_HOST;
 403         }
 404 }
 405
 406 static void vsock_deassign_transport(struct vsock_sock *vsk)
 407 {
 408         if (!vsk->transport)
 409                 return;
 410
 411         vsk->transport->destruct(vsk);
 412         module_put(vsk->transport->module);
 413         vsk->transport = NULL;
 414 }
 415
 416 /* Assign a transport to a socket and call the .init transport callback.
 417  *
 418  * Note: for stream socket this must be called when vsk->remote_addr is set
 419  * (e.g. during the connect() or when a connection request on a listener
 420  * socket is received).
 421  * The vsk->remote_addr is used to decide which transport to use:
 422  *  - remote CID == VMADDR_CID_LOCAL or g2h->local_cid or VMADDR_CID_HOST if
 423  *    g2h is not loaded, will use local transport;
 424  *  - remote CID <= VMADDR_CID_HOST will use guest->host transport;
 425  *  - remote CID > VMADDR_CID_HOST will use host->guest transport;
 426  */
 427 int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk)
 428 {
 429         const struct vsock_transport *new_transport;
 430         struct sock *sk = sk_vsock(vsk);
 431         unsigned int remote_cid = vsk->remote_addr.svm_cid;
 432         int ret;
 433
 434         switch (sk->sk_type) {
 435         case SOCK_DGRAM:
 436                 new_transport = transport_dgram;
 437                 break;
 438         case SOCK_STREAM:
 439                 if (vsock_use_local_transport(remote_cid))
 440                         new_transport = transport_local;
 441                 else if (remote_cid <= VMADDR_CID_HOST)
 442                         new_transport = transport_g2h;
 443                 else
 444                         new_transport = transport_h2g;
 445                 break;
 446         default:
 447                 return -ESOCKTNOSUPPORT;
 448         }
 449
 450         if (vsk->transport) {
 451                 if (vsk->transport == new_transport)
 452                         return 0;
 453
 454                 /* transport->release() must be called with sock lock acquired.
 455                  * This path can only be taken during vsock_stream_connect(),
 456                  * where we have already held the sock lock.
 457                  * In the other cases, this function is called on a new socket
 458                  * which is not assigned to any transport.
 459                  */
 460                 vsk->transport->release(vsk);
 461                 vsock_deassign_transport(vsk);
 462         }
 463
 464         /* We increase the module refcnt to prevent the transport unloading
 465          * while there are open sockets assigned to it.
 466          */
 467         if (!new_transport || !try_module_get(new_transport->module))
 468                 return -ENODEV;
 469
 470         ret = new_transport->init(vsk, psk);
 471         if (ret) {
 472                 module_put(new_transport->module);
 473                 return ret;
 474         }
 475
 476         vsk->transport = new_transport;
 477
 478         return 0;
 479 }
 480 EXPORT_SYMBOL_GPL(vsock_assign_transport);
 481
 482 bool vsock_find_cid(unsigned int cid)
 483 {
 484         if (transport_g2h && cid == transport_g2h->get_local_cid())
 485                 return true;
 486
 487         if (transport_h2g && cid == VMADDR_CID_HOST)
 488                 return true;
 489
 490         if (transport_local && cid == VMADDR_CID_LOCAL)
 491                 return true;
 492
 493         return false;
 494 }
 495 EXPORT_SYMBOL_GPL(vsock_find_cid);
 496
 497 static struct sock *vsock_dequeue_accept(struct sock *listener)
 498 {
 499         struct vsock_sock *vlistener;
 500         struct vsock_sock *vconnected;
 501
 502         vlistener = vsock_sk(listener);
 503
 504         if (list_empty(&vlistener->accept_queue))
 505                 return NULL;
 506
 507         vconnected = list_entry(vlistener->accept_queue.next,
 508                                 struct vsock_sock, accept_queue);
 509
 510         list_del_init(&vconnected->accept_queue);
 511         sock_put(listener);
 512         /* The caller will need a reference on the connected socket so we let
 513          * it call sock_put().
 514          */
 515
 516         return sk_vsock(vconnected);
 517 }
 518
 519 static bool vsock_is_accept_queue_empty(struct sock *sk)
 520 {
 521         struct vsock_sock *vsk = vsock_sk(sk);
 522         return list_empty(&vsk->accept_queue);
 523 }
 524
 525 static bool vsock_is_pending(struct sock *sk)
 526 {
 527         struct vsock_sock *vsk = vsock_sk(sk);
 528         return !list_empty(&vsk->pending_links);
 529 }
 530
 531 static int vsock_send_shutdown(struct sock *sk, int mode)
 532 {
 533         struct vsock_sock *vsk = vsock_sk(sk);
 534
 535         if (!vsk->transport)
 536                 return -ENODEV;
 537
 538         return vsk->transport->shutdown(vsk, mode);
 539 }
 540
 541 static void vsock_pending_work(struct work_struct *work)
 542 {
 543         struct sock *sk;
 544         struct sock *listener;
 545         struct vsock_sock *vsk;
 546         bool cleanup;
 547
 548         vsk = container_of(work, struct vsock_sock, pending_work.work);
 549         sk = sk_vsock(vsk);
 550         listener = vsk->listener;
 551         cleanup = true;
 552
 553         lock_sock(listener);
 554         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 555
 556         if (vsock_is_pending(sk)) {
 557                 vsock_remove_pending(listener, sk);
 558
 559                 sk_acceptq_removed(listener);
 560         } else if (!vsk->rejected) {
 561                 /* We are not on the pending list and accept() did not reject
 562                  * us, so we must have been accepted by our user process.  We
 563                  * just need to drop our references to the sockets and be on
 564                  * our way.
 565                  */
 566                 cleanup = false;
 567                 goto out;
 568         }
 569
 570         /* We need to remove ourself from the global connected sockets list so
 571          * incoming packets can't find this socket, and to reduce the reference
 572          * count.
 573          */
 574         vsock_remove_connected(vsk);
 575
 576         sk->sk_state = TCP_CLOSE;
 577
 578 out:
 579         release_sock(sk);
 580         release_sock(listener);
 581         if (cleanup)
 582                 sock_put(sk);
 583
 584         sock_put(sk);
 585         sock_put(listener);
 586 }
 587
 588 /**** SOCKET OPERATIONS ****/
 589
 590 static int __vsock_bind_stream(struct vsock_sock *vsk,
 591                                struct sockaddr_vm *addr)
 592 {
 593         static u32 port;
 594         struct sockaddr_vm new_addr;
 595
 596         if (!port)
 597                 port = LAST_RESERVED_PORT + 1 +
 598                         prandom_u32_max(U32_MAX - LAST_RESERVED_PORT);
 599
 600         vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port);
 601
 602         if (addr->svm_port == VMADDR_PORT_ANY) {
 603                 bool found = false;
 604                 unsigned int i;
 605
 606                 for (i = 0; i < MAX_PORT_RETRIES; i++) {
 607                         if (port <= LAST_RESERVED_PORT)
 608                                 port = LAST_RESERVED_PORT + 1;
 609
 610                         new_addr.svm_port = port++;
 611
 612                         if (!__vsock_find_bound_socket(&new_addr)) {
 613                                 found = true;
 614                                 break;
 615                         }
 616                 }
 617
 618                 if (!found)
 619                         return -EADDRNOTAVAIL;
 620         } else {
 621                 /* If port is in reserved range, ensure caller
 622                  * has necessary privileges.
 623                  */
 624                 if (addr->svm_port <= LAST_RESERVED_PORT &&
 625                     !capable(CAP_NET_BIND_SERVICE)) {
 626                         return -EACCES;
 627                 }
 628
 629                 if (__vsock_find_bound_socket(&new_addr))
 630                         return -EADDRINUSE;
 631         }
 632
 633         vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port);
 634
 635         /* Remove stream sockets from the unbound list and add them to the hash
 636          * table for easy lookup by its address.  The unbound list is simply an
 637          * extra entry at the end of the hash table, a trick used by AF_UNIX.
 638          */
 639         __vsock_remove_bound(vsk);
 640         __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk);
 641
 642         return 0;
 643 }
 644
 645 static int __vsock_bind_dgram(struct vsock_sock *vsk,
 646                               struct sockaddr_vm *addr)
 647 {
 648         return vsk->transport->dgram_bind(vsk, addr);
 649 }
 650
 651 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr)
 652 {
 653         struct vsock_sock *vsk = vsock_sk(sk);
 654         int retval;
 655
 656         /* First ensure this socket isn't already bound. */
 657         if (vsock_addr_bound(&vsk->local_addr))
 658                 return -EINVAL;
 659
 660         /* Now bind to the provided address or select appropriate values if
 661          * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY).  Note that
 662          * like AF_INET prevents binding to a non-local IP address (in most
 663          * cases), we only allow binding to a local CID.
 664          */
 665         if (addr->svm_cid != VMADDR_CID_ANY && !vsock_find_cid(addr->svm_cid))
 666                 return -EADDRNOTAVAIL;
 667
 668         switch (sk->sk_socket->type) {
 669         case SOCK_STREAM:
 670                 spin_lock_bh(&vsock_table_lock);
 671                 retval = __vsock_bind_stream(vsk, addr);
 672                 spin_unlock_bh(&vsock_table_lock);
 673                 break;
 674
 675         case SOCK_DGRAM:
 676                 retval = __vsock_bind_dgram(vsk, addr);
 677                 break;
 678
 679         default:
 680                 retval = -EINVAL;
 681                 break;
 682         }
 683
 684         return retval;
 685 }
 686
 687 static void vsock_connect_timeout(struct work_struct *work);
 688
 689 static struct sock *__vsock_create(struct net *net,
 690                                    struct socket *sock,
 691                                    struct sock *parent,
 692                                    gfp_t priority,
 693                                    unsigned short type,
 694                                    int kern)
 695 {
 696         struct sock *sk;
 697         struct vsock_sock *psk;
 698         struct vsock_sock *vsk;
 699
 700         sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto, kern);
 701         if (!sk)
 702                 return NULL;
 703
 704         sock_init_data(sock, sk);
 705
 706         /* sk->sk_type is normally set in sock_init_data, but only if sock is
 707          * non-NULL. We make sure that our sockets always have a type by
 708          * setting it here if needed.
 709          */
 710         if (!sock)
 711                 sk->sk_type = type;
 712
 713         vsk = vsock_sk(sk);
 714         vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 715         vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 716
 717         sk->sk_destruct = vsock_sk_destruct;
 718         sk->sk_backlog_rcv = vsock_queue_rcv_skb;
 719         sock_reset_flag(sk, SOCK_DONE);
 720
 721         INIT_LIST_HEAD(&vsk->bound_table);
 722         INIT_LIST_HEAD(&vsk->connected_table);
 723         vsk->listener = NULL;
 724         INIT_LIST_HEAD(&vsk->pending_links);
 725         INIT_LIST_HEAD(&vsk->accept_queue);
 726         vsk->rejected = false;
 727         vsk->sent_request = false;
 728         vsk->ignore_connecting_rst = false;
 729         vsk->peer_shutdown = 0;
 730         INIT_DELAYED_WORK(&vsk->connect_work, vsock_connect_timeout);
 731         INIT_DELAYED_WORK(&vsk->pending_work, vsock_pending_work);
 732
 733         psk = parent ? vsock_sk(parent) : NULL;
 734         if (parent) {
 735                 vsk->trusted = psk->trusted;
 736                 vsk->owner = get_cred(psk->owner);
 737                 vsk->connect_timeout = psk->connect_timeout;
 738                 vsk->buffer_size = psk->buffer_size;
 739                 vsk->buffer_min_size = psk->buffer_min_size;
 740                 vsk->buffer_max_size = psk->buffer_max_size;
 741         } else {
 742                 vsk->trusted = capable(CAP_NET_ADMIN);
 743                 vsk->owner = get_current_cred();
 744                 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT;
 745                 vsk->buffer_size = VSOCK_DEFAULT_BUFFER_SIZE;
 746                 vsk->buffer_min_size = VSOCK_DEFAULT_BUFFER_MIN_SIZE;
 747                 vsk->buffer_max_size = VSOCK_DEFAULT_BUFFER_MAX_SIZE;
 748         }
 749
 750         return sk;
 751 }
 752
 753 static void __vsock_release(struct sock *sk, int level)
 754 {
 755         if (sk) {
 756                 struct sock *pending;
 757                 struct vsock_sock *vsk;
 758
 759                 vsk = vsock_sk(sk);
 760                 pending = NULL; /* Compiler warning. */
 761
 762                 /* When "level" is SINGLE_DEPTH_NESTING, use the nested
 763                  * version to avoid the warning "possible recursive locking
 764                  * detected". When "level" is 0, lock_sock_nested(sk, level)
 765                  * is the same as lock_sock(sk).
 766                  */
 767                 lock_sock_nested(sk, level);
 768
 769                 if (vsk->transport)
 770                         vsk->transport->release(vsk);
 771                 else if (sk->sk_type == SOCK_STREAM)
 772                         vsock_remove_sock(vsk);
 773
 774                 sock_orphan(sk);
 775                 sk->sk_shutdown = SHUTDOWN_MASK;
 776
 777                 skb_queue_purge(&sk->sk_receive_queue);
 778
 779                 /* Clean up any sockets that never were accepted. */
 780                 while ((pending = vsock_dequeue_accept(sk)) != NULL) {
 781                         __vsock_release(pending, SINGLE_DEPTH_NESTING);
 782                         sock_put(pending);
 783                 }
 784
 785                 release_sock(sk);
 786                 sock_put(sk);
 787         }
 788 }
 789
 790 static void vsock_sk_destruct(struct sock *sk)
 791 {
 792         struct vsock_sock *vsk = vsock_sk(sk);
 793
 794         vsock_deassign_transport(vsk);
 795
 796         /* When clearing these addresses, there's no need to set the family and
 797          * possibly register the address family with the kernel.
 798          */
 799         vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 800         vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 801
 802         put_cred(vsk->owner);
 803 }
 804
 805 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 806 {
 807         int err;
 808
 809         err = sock_queue_rcv_skb(sk, skb);
 810         if (err)
 811                 kfree_skb(skb);
 812
 813         return err;
 814 }
 815
 816 struct sock *vsock_create_connected(struct sock *parent)
 817 {
 818         return __vsock_create(sock_net(parent), NULL, parent, GFP_KERNEL,
 819                               parent->sk_type, 0);
 820 }
 821 EXPORT_SYMBOL_GPL(vsock_create_connected);
 822
 823 s64 vsock_stream_has_data(struct vsock_sock *vsk)
 824 {
 825         return vsk->transport->stream_has_data(vsk);
 826 }
 827 EXPORT_SYMBOL_GPL(vsock_stream_has_data);
 828
 829 s64 vsock_stream_has_space(struct vsock_sock *vsk)
 830 {
 831         return vsk->transport->stream_has_space(vsk);
 832 }
 833 EXPORT_SYMBOL_GPL(vsock_stream_has_space);
 834
 835 static int vsock_release(struct socket *sock)
 836 {
 837         __vsock_release(sock->sk, 0);
 838         sock->sk = NULL;
 839         sock->state = SS_FREE;
 840
 841         return 0;
 842 }
 843
 844 static int
 845 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
 846 {
 847         int err;
 848         struct sock *sk;
 849         struct sockaddr_vm *vm_addr;
 850
 851         sk = sock->sk;
 852
 853         if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0)
 854                 return -EINVAL;
 855
 856         lock_sock(sk);
 857         err = __vsock_bind(sk, vm_addr);
 858         release_sock(sk);
 859
 860         return err;
 861 }
 862
 863 static int vsock_getname(struct socket *sock,
 864                          struct sockaddr *addr, int peer)
 865 {
 866         int err;
 867         struct sock *sk;
 868         struct vsock_sock *vsk;
 869         struct sockaddr_vm *vm_addr;
 870
 871         sk = sock->sk;
 872         vsk = vsock_sk(sk);
 873         err = 0;
 874
 875         lock_sock(sk);
 876
 877         if (peer) {
 878                 if (sock->state != SS_CONNECTED) {
 879                         err = -ENOTCONN;
 880                         goto out;
 881                 }
 882                 vm_addr = &vsk->remote_addr;
 883         } else {
 884                 vm_addr = &vsk->local_addr;
 885         }
 886
 887         if (!vm_addr) {
 888                 err = -EINVAL;
 889                 goto out;
 890         }
 891
 892         /* sys_getsockname() and sys_getpeername() pass us a
 893          * MAX_SOCK_ADDR-sized buffer and don't set addr_len.  Unfortunately
 894          * that macro is defined in socket.c instead of .h, so we hardcode its
 895          * value here.
 896          */
 897         BUILD_BUG_ON(sizeof(*vm_addr) > 128);
 898         memcpy(addr, vm_addr, sizeof(*vm_addr));
 899         err = sizeof(*vm_addr);
 900
 901 out:
 902         release_sock(sk);
 903         return err;
 904 }
 905
 906 static int vsock_shutdown(struct socket *sock, int mode)
 907 {
 908         int err;
 909         struct sock *sk;
 910
 911         /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses
 912          * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode
 913          * here like the other address families do.  Note also that the
 914          * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3),
 915          * which is what we want.
 916          */
 917         mode++;
 918
 919         if ((mode & ~SHUTDOWN_MASK) || !mode)
 920                 return -EINVAL;
 921
 922         /* If this is a STREAM socket and it is not connected then bail out
 923          * immediately.  If it is a DGRAM socket then we must first kick the
 924          * socket so that it wakes up from any sleeping calls, for example
 925          * recv(), and then afterwards return the error.
 926          */
 927
 928         sk = sock->sk;
 929         if (sock->state == SS_UNCONNECTED) {
 930                 err = -ENOTCONN;
 931                 if (sk->sk_type == SOCK_STREAM)
 932                         return err;
 933         } else {
 934                 sock->state = SS_DISCONNECTING;
 935                 err = 0;
 936         }
 937
 938         /* Receive and send shutdowns are treated alike. */
 939         mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN);
 940         if (mode) {
 941                 lock_sock(sk);
 942                 sk->sk_shutdown |= mode;
 943                 sk->sk_state_change(sk);
 944                 release_sock(sk);
 945
 946                 if (sk->sk_type == SOCK_STREAM) {
 947                         sock_reset_flag(sk, SOCK_DONE);
 948                         vsock_send_shutdown(sk, mode);
 949                 }
 950         }
 951
 952         return err;
 953 }
 954
 955 static __poll_t vsock_poll(struct file *file, struct socket *sock,
 956                                poll_table *wait)
 957 {
 958         struct sock *sk;
 959         __poll_t mask;
 960         struct vsock_sock *vsk;
 961
 962         sk = sock->sk;
 963         vsk = vsock_sk(sk);
 964
 965         poll_wait(file, sk_sleep(sk), wait);
 966         mask = 0;
 967
 968         if (sk->sk_err)
 969                 /* Signify that there has been an error on this socket. */
 970                 mask |= EPOLLERR;
 971
 972         /* INET sockets treat local write shutdown and peer write shutdown as a
 973          * case of EPOLLHUP set.
 974          */
 975         if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
 976             ((sk->sk_shutdown & SEND_SHUTDOWN) &&
 977              (vsk->peer_shutdown & SEND_SHUTDOWN))) {
 978                 mask |= EPOLLHUP;
 979         }
 980
 981         if (sk->sk_shutdown & RCV_SHUTDOWN ||
 982             vsk->peer_shutdown & SEND_SHUTDOWN) {
 983                 mask |= EPOLLRDHUP;
 984         }
 985
 986         if (sock->type == SOCK_DGRAM) {
 987                 /* For datagram sockets we can read if there is something in
 988                  * the queue and write as long as the socket isn't shutdown for
 989                  * sending.
 990                  */
 991                 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) ||
 992                     (sk->sk_shutdown & RCV_SHUTDOWN)) {
 993                         mask |= EPOLLIN | EPOLLRDNORM;
 994                 }
 995
 996                 if (!(sk->sk_shutdown & SEND_SHUTDOWN))
 997                         mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
 998
 999         } else if (sock->type == SOCK_STREAM) {
1000                 const struct vsock_transport *transport = vsk->transport;
1001                 lock_sock(sk);
1002
1003                 /* Listening sockets that have connections in their accept
1004                  * queue can be read.
1005                  */
1006                 if (sk->sk_state == TCP_LISTEN
1007                     && !vsock_is_accept_queue_empty(sk))
1008                         mask |= EPOLLIN | EPOLLRDNORM;
1009
1010                 /* If there is something in the queue then we can read. */
1011                 if (transport && transport->stream_is_active(vsk) &&
1012                     !(sk->sk_shutdown & RCV_SHUTDOWN)) {
1013                         bool data_ready_now = false;
1014                         int ret = transport->notify_poll_in(
1015                                         vsk, 1, &data_ready_now);
1016                         if (ret < 0) {
1017                                 mask |= EPOLLERR;
1018                         } else {
1019                                 if (data_ready_now)
1020                                         mask |= EPOLLIN | EPOLLRDNORM;
1021
1022                         }
1023                 }
1024
1025                 /* Sockets whose connections have been closed, reset, or
1026                  * terminated should also be considered read, and we check the
1027                  * shutdown flag for that.
1028                  */
1029                 if (sk->sk_shutdown & RCV_SHUTDOWN ||
1030                     vsk->peer_shutdown & SEND_SHUTDOWN) {
1031                         mask |= EPOLLIN | EPOLLRDNORM;
1032                 }
1033
1034                 /* Connected sockets that can produce data can be written. */
1035                 if (sk->sk_state == TCP_ESTABLISHED) {
1036                         if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1037                                 bool space_avail_now = false;
1038                                 int ret = transport->notify_poll_out(
1039                                                 vsk, 1, &space_avail_now);
1040                                 if (ret < 0) {
1041                                         mask |= EPOLLERR;
1042                                 } else {
1043                                         if (space_avail_now)
1044                                                 /* Remove EPOLLWRBAND since INET
1045                                                  * sockets are not setting it.
1046                                                  */
1047                                                 mask |= EPOLLOUT | EPOLLWRNORM;
1048
1049                                 }
1050                         }
1051                 }
1052
1053                 /* Simulate INET socket poll behaviors, which sets
1054                  * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read,
1055                  * but local send is not shutdown.
1056                  */
1057                 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) {
1058                         if (!(sk->sk_shutdown & SEND_SHUTDOWN))
1059                                 mask |= EPOLLOUT | EPOLLWRNORM;
1060
1061                 }
1062
1063                 release_sock(sk);
1064         }
1065
1066         return mask;
1067 }
1068
1069 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
1070                                size_t len)
1071 {
1072         int err;
1073         struct sock *sk;
1074         struct vsock_sock *vsk;
1075         struct sockaddr_vm *remote_addr;
1076         const struct vsock_transport *transport;
1077
1078         if (msg->msg_flags & MSG_OOB)
1079                 return -EOPNOTSUPP;
1080
1081         /* For now, MSG_DONTWAIT is always assumed... */
1082         err = 0;
1083         sk = sock->sk;
1084         vsk = vsock_sk(sk);
1085         transport = vsk->transport;
1086
1087         lock_sock(sk);
1088
1089         err = vsock_auto_bind(vsk);
1090         if (err)
1091                 goto out;
1092
1093
1094         /* If the provided message contains an address, use that.  Otherwise
1095          * fall back on the socket's remote handle (if it has been connected).
1096          */
1097         if (msg->msg_name &&
1098             vsock_addr_cast(msg->msg_name, msg->msg_namelen,
1099                             &remote_addr) == 0) {
1100                 /* Ensure this address is of the right type and is a valid
1101                  * destination.
1102                  */
1103
1104                 if (remote_addr->svm_cid == VMADDR_CID_ANY)
1105                         remote_addr->svm_cid = transport->get_local_cid();
1106
1107                 if (!vsock_addr_bound(remote_addr)) {
1108                         err = -EINVAL;
1109                         goto out;
1110                 }
1111         } else if (sock->state == SS_CONNECTED) {
1112                 remote_addr = &vsk->remote_addr;
1113
1114                 if (remote_addr->svm_cid == VMADDR_CID_ANY)
1115                         remote_addr->svm_cid = transport->get_local_cid();
1116
1117                 /* XXX Should connect() or this function ensure remote_addr is
1118                  * bound?
1119                  */
1120                 if (!vsock_addr_bound(&vsk->remote_addr)) {
1121                         err = -EINVAL;
1122                         goto out;
1123                 }
1124         } else {
1125                 err = -EINVAL;
1126                 goto out;
1127         }
1128
1129         if (!transport->dgram_allow(remote_addr->svm_cid,
1130                                     remote_addr->svm_port)) {
1131                 err = -EINVAL;
1132                 goto out;
1133         }
1134
1135         err = transport->dgram_enqueue(vsk, remote_addr, msg, len);
1136
1137 out:
1138         release_sock(sk);
1139         return err;
1140 }
1141
1142 static int vsock_dgram_connect(struct socket *sock,
1143                                struct sockaddr *addr, int addr_len, int flags)
1144 {
1145         int err;
1146         struct sock *sk;
1147         struct vsock_sock *vsk;
1148         struct sockaddr_vm *remote_addr;
1149
1150         sk = sock->sk;
1151         vsk = vsock_sk(sk);
1152
1153         err = vsock_addr_cast(addr, addr_len, &remote_addr);
1154         if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) {
1155                 lock_sock(sk);
1156                 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY,
1157                                 VMADDR_PORT_ANY);
1158                 sock->state = SS_UNCONNECTED;
1159                 release_sock(sk);
1160                 return 0;
1161         } else if (err != 0)
1162                 return -EINVAL;
1163
1164         lock_sock(sk);
1165
1166         err = vsock_auto_bind(vsk);
1167         if (err)
1168                 goto out;
1169
1170         if (!vsk->transport->dgram_allow(remote_addr->svm_cid,
1171                                          remote_addr->svm_port)) {
1172                 err = -EINVAL;
1173                 goto out;
1174         }
1175
1176         memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr));
1177         sock->state = SS_CONNECTED;
1178
1179 out:
1180         release_sock(sk);
1181         return err;
1182 }
1183
1184 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg,
1185                                size_t len, int flags)
1186 {
1187         struct vsock_sock *vsk = vsock_sk(sock->sk);
1188
1189         return vsk->transport->dgram_dequeue(vsk, msg, len, flags);
1190 }
1191
1192 static const struct proto_ops vsock_dgram_ops = {
1193         .family = PF_VSOCK,
1194         .owner = THIS_MODULE,
1195         .release = vsock_release,
1196         .bind = vsock_bind,
1197         .connect = vsock_dgram_connect,
1198         .socketpair = sock_no_socketpair,
1199         .accept = sock_no_accept,
1200         .getname = vsock_getname,
1201         .poll = vsock_poll,
1202         .ioctl = sock_no_ioctl,
1203         .listen = sock_no_listen,
1204         .shutdown = vsock_shutdown,
1205         .setsockopt = sock_no_setsockopt,
1206         .getsockopt = sock_no_getsockopt,
1207         .sendmsg = vsock_dgram_sendmsg,
1208         .recvmsg = vsock_dgram_recvmsg,
1209         .mmap = sock_no_mmap,
1210         .sendpage = sock_no_sendpage,
1211 };
1212
1213 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk)
1214 {
1215         const struct vsock_transport *transport = vsk->transport;
1216
1217         if (!transport->cancel_pkt)
1218                 return -EOPNOTSUPP;
1219
1220         return transport->cancel_pkt(vsk);
1221 }
1222
1223 static void vsock_connect_timeout(struct work_struct *work)
1224 {
1225         struct sock *sk;
1226         struct vsock_sock *vsk;
1227         int cancel = 0;
1228
1229         vsk = container_of(work, struct vsock_sock, connect_work.work);
1230         sk = sk_vsock(vsk);
1231
1232         lock_sock(sk);
1233         if (sk->sk_state == TCP_SYN_SENT &&
1234             (sk->sk_shutdown != SHUTDOWN_MASK)) {
1235                 sk->sk_state = TCP_CLOSE;
1236                 sk->sk_err = ETIMEDOUT;
1237                 sk->sk_error_report(sk);
1238                 cancel = 1;
1239         }
1240         release_sock(sk);
1241         if (cancel)
1242                 vsock_transport_cancel_pkt(vsk);
1243
1244         sock_put(sk);
1245 }
1246
1247 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
1248                                 int addr_len, int flags)
1249 {
1250         int err;
1251         struct sock *sk;
1252         struct vsock_sock *vsk;
1253         const struct vsock_transport *transport;
1254         struct sockaddr_vm *remote_addr;
1255         long timeout;
1256         DEFINE_WAIT(wait);
1257
1258         err = 0;
1259         sk = sock->sk;
1260         vsk = vsock_sk(sk);
1261
1262         lock_sock(sk);
1263
1264         /* XXX AF_UNSPEC should make us disconnect like AF_INET. */
1265         switch (sock->state) {
1266         case SS_CONNECTED:
1267                 err = -EISCONN;
1268                 goto out;
1269         case SS_DISCONNECTING:
1270                 err = -EINVAL;
1271                 goto out;
1272         case SS_CONNECTING:
1273                 /* This continues on so we can move sock into the SS_CONNECTED
1274                  * state once the connection has completed (at which point err
1275                  * will be set to zero also).  Otherwise, we will either wait
1276                  * for the connection or return -EALREADY should this be a
1277                  * non-blocking call.
1278                  */
1279                 err = -EALREADY;
1280                 break;
1281         default:
1282                 if ((sk->sk_state == TCP_LISTEN) ||
1283                     vsock_addr_cast(addr, addr_len, &remote_addr) != 0) {
1284                         err = -EINVAL;
1285                         goto out;
1286                 }
1287
1288                 /* Set the remote address that we are connecting to. */
1289                 memcpy(&vsk->remote_addr, remote_addr,
1290                        sizeof(vsk->remote_addr));
1291
1292                 err = vsock_assign_transport(vsk, NULL);
1293                 if (err)
1294                         goto out;
1295
1296                 transport = vsk->transport;
1297
1298                 /* The hypervisor and well-known contexts do not have socket
1299                  * endpoints.
1300                  */
1301                 if (!transport ||
1302                     !transport->stream_allow(remote_addr->svm_cid,
1303                                              remote_addr->svm_port)) {
1304                         err = -ENETUNREACH;
1305                         goto out;
1306                 }
1307
1308                 err = vsock_auto_bind(vsk);
1309                 if (err)
1310                         goto out;
1311
1312                 sk->sk_state = TCP_SYN_SENT;
1313
1314                 err = transport->connect(vsk);
1315                 if (err < 0)
1316                         goto out;
1317
1318                 /* Mark sock as connecting and set the error code to in
1319                  * progress in case this is a non-blocking connect.
1320                  */
1321                 sock->state = SS_CONNECTING;
1322                 err = -EINPROGRESS;
1323         }
1324
1325         /* The receive path will handle all communication until we are able to
1326          * enter the connected state.  Here we wait for the connection to be
1327          * completed or a notification of an error.
1328          */
1329         timeout = vsk->connect_timeout;
1330         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1331
1332         while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) {
1333                 if (flags & O_NONBLOCK) {
1334                         /* If we're not going to block, we schedule a timeout
1335                          * function to generate a timeout on the connection
1336                          * attempt, in case the peer doesn't respond in a
1337                          * timely manner. We hold on to the socket until the
1338                          * timeout fires.
1339                          */
1340                         sock_hold(sk);
1341                         schedule_delayed_work(&vsk->connect_work, timeout);
1342
1343                         /* Skip ahead to preserve error code set above. */
1344                         goto out_wait;
1345                 }
1346
1347                 release_sock(sk);
1348                 timeout = schedule_timeout(timeout);
1349                 lock_sock(sk);
1350
1351                 if (signal_pending(current)) {
1352                         err = sock_intr_errno(timeout);
1353                         sk->sk_state = TCP_CLOSE;
1354                         sock->state = SS_UNCONNECTED;
1355                         vsock_transport_cancel_pkt(vsk);
1356                         goto out_wait;
1357                 } else if (timeout == 0) {
1358                         err = -ETIMEDOUT;
1359                         sk->sk_state = TCP_CLOSE;
1360                         sock->state = SS_UNCONNECTED;
1361                         vsock_transport_cancel_pkt(vsk);
1362                         goto out_wait;
1363                 }
1364
1365                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1366         }
1367
1368         if (sk->sk_err) {
1369                 err = -sk->sk_err;
1370                 sk->sk_state = TCP_CLOSE;
1371                 sock->state = SS_UNCONNECTED;
1372         } else {
1373                 err = 0;
1374         }
1375
1376 out_wait:
1377         finish_wait(sk_sleep(sk), &wait);
1378 out:
1379         release_sock(sk);
1380         return err;
1381 }
1382
1383 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags,
1384                         bool kern)
1385 {
1386         struct sock *listener;
1387         int err;
1388         struct sock *connected;
1389         struct vsock_sock *vconnected;
1390         long timeout;
1391         DEFINE_WAIT(wait);
1392
1393         err = 0;
1394         listener = sock->sk;
1395
1396         lock_sock(listener);
1397
1398         if (sock->type != SOCK_STREAM) {
1399                 err = -EOPNOTSUPP;
1400                 goto out;
1401         }
1402
1403         if (listener->sk_state != TCP_LISTEN) {
1404                 err = -EINVAL;
1405                 goto out;
1406         }
1407
1408         /* Wait for children sockets to appear; these are the new sockets
1409          * created upon connection establishment.
1410          */
1411         timeout = sock_rcvtimeo(listener, flags & O_NONBLOCK);
1412         prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1413
1414         while ((connected = vsock_dequeue_accept(listener)) == NULL &&
1415                listener->sk_err == 0) {
1416                 release_sock(listener);
1417                 timeout = schedule_timeout(timeout);
1418                 finish_wait(sk_sleep(listener), &wait);
1419                 lock_sock(listener);
1420
1421                 if (signal_pending(current)) {
1422                         err = sock_intr_errno(timeout);
1423                         goto out;
1424                 } else if (timeout == 0) {
1425                         err = -EAGAIN;
1426                         goto out;
1427                 }
1428
1429                 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1430         }
1431         finish_wait(sk_sleep(listener), &wait);
1432
1433         if (listener->sk_err)
1434                 err = -listener->sk_err;
1435
1436         if (connected) {
1437                 sk_acceptq_removed(listener);
1438
1439                 lock_sock_nested(connected, SINGLE_DEPTH_NESTING);
1440                 vconnected = vsock_sk(connected);
1441
1442                 /* If the listener socket has received an error, then we should
1443                  * reject this socket and return.  Note that we simply mark the
1444                  * socket rejected, drop our reference, and let the cleanup
1445                  * function handle the cleanup; the fact that we found it in
1446                  * the listener's accept queue guarantees that the cleanup
1447                  * function hasn't run yet.
1448                  */
1449                 if (err) {
1450                         vconnected->rejected = true;
1451                 } else {
1452                         newsock->state = SS_CONNECTED;
1453                         sock_graft(connected, newsock);
1454                 }
1455
1456                 release_sock(connected);
1457                 sock_put(connected);
1458         }
1459
1460 out:
1461         release_sock(listener);
1462         return err;
1463 }
1464
1465 static int vsock_listen(struct socket *sock, int backlog)
1466 {
1467         int err;
1468         struct sock *sk;
1469         struct vsock_sock *vsk;
1470
1471         sk = sock->sk;
1472
1473         lock_sock(sk);
1474
1475         if (sock->type != SOCK_STREAM) {
1476                 err = -EOPNOTSUPP;
1477                 goto out;
1478         }
1479
1480         if (sock->state != SS_UNCONNECTED) {
1481                 err = -EINVAL;
1482                 goto out;
1483         }
1484
1485         vsk = vsock_sk(sk);
1486
1487         if (!vsock_addr_bound(&vsk->local_addr)) {
1488                 err = -EINVAL;
1489                 goto out;
1490         }
1491
1492         sk->sk_max_ack_backlog = backlog;
1493         sk->sk_state = TCP_LISTEN;
1494
1495         err = 0;
1496
1497 out:
1498         release_sock(sk);
1499         return err;
1500 }
1501
1502 static void vsock_update_buffer_size(struct vsock_sock *vsk,
1503                                      const struct vsock_transport *transport,
1504                                      u64 val)
1505 {
1506         if (val > vsk->buffer_max_size)
1507                 val = vsk->buffer_max_size;
1508
1509         if (val < vsk->buffer_min_size)
1510                 val = vsk->buffer_min_size;
1511
1512         if (val != vsk->buffer_size &&
1513             transport && transport->notify_buffer_size)
1514                 transport->notify_buffer_size(vsk, &val);
1515
1516         vsk->buffer_size = val;
1517 }
1518
1519 static int vsock_stream_setsockopt(struct socket *sock,
1520                                    int level,
1521                                    int optname,
1522                                    char __user *optval,
1523                                    unsigned int optlen)
1524 {
1525         int err;
1526         struct sock *sk;
1527         struct vsock_sock *vsk;
1528         const struct vsock_transport *transport;
1529         u64 val;
1530
1531         if (level != AF_VSOCK)
1532                 return -ENOPROTOOPT;
1533
1534 #define COPY_IN(_v)                                       \
1535         do {                                              \
1536                 if (optlen < sizeof(_v)) {                \
1537                         err = -EINVAL;                    \
1538                         goto exit;                        \
1539                 }                                         \
1540                 if (copy_from_user(&_v, optval, sizeof(_v)) != 0) {     \
1541                         err = -EFAULT;                                  \
1542                         goto exit;                                      \
1543                 }                                                       \
1544         } while (0)
1545
1546         err = 0;
1547         sk = sock->sk;
1548         vsk = vsock_sk(sk);
1549         transport = vsk->transport;
1550
1551         lock_sock(sk);
1552
1553         switch (optname) {
1554         case SO_VM_SOCKETS_BUFFER_SIZE:
1555                 COPY_IN(val);
1556                 vsock_update_buffer_size(vsk, transport, val);
1557                 break;
1558
1559         case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1560                 COPY_IN(val);
1561                 vsk->buffer_max_size = val;
1562                 vsock_update_buffer_size(vsk, transport, vsk->buffer_size);
1563                 break;
1564
1565         case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1566                 COPY_IN(val);
1567                 vsk->buffer_min_size = val;
1568                 vsock_update_buffer_size(vsk, transport, vsk->buffer_size);
1569                 break;
1570
1571         case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1572                 struct __kernel_old_timeval tv;
1573                 COPY_IN(tv);
1574                 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC &&
1575                     tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) {
1576                         vsk->connect_timeout = tv.tv_sec * HZ +
1577                             DIV_ROUND_UP(tv.tv_usec, (1000000 / HZ));
1578                         if (vsk->connect_timeout == 0)
1579                                 vsk->connect_timeout =
1580                                     VSOCK_DEFAULT_CONNECT_TIMEOUT;
1581
1582                 } else {
1583                         err = -ERANGE;
1584                 }
1585                 break;
1586         }
1587
1588         default:
1589                 err = -ENOPROTOOPT;
1590                 break;
1591         }
1592
1593 #undef COPY_IN
1594
1595 exit:
1596         release_sock(sk);
1597         return err;
1598 }
1599
1600 static int vsock_stream_getsockopt(struct socket *sock,
1601                                    int level, int optname,
1602                                    char __user *optval,
1603                                    int __user *optlen)
1604 {
1605         int err;
1606         int len;
1607         struct sock *sk;
1608         struct vsock_sock *vsk;
1609         u64 val;
1610
1611         if (level != AF_VSOCK)
1612                 return -ENOPROTOOPT;
1613
1614         err = get_user(len, optlen);
1615         if (err != 0)
1616                 return err;
1617
1618 #define COPY_OUT(_v)                            \
1619         do {                                    \
1620                 if (len < sizeof(_v))           \
1621                         return -EINVAL;         \
1622                                                 \
1623                 len = sizeof(_v);               \
1624                 if (copy_to_user(optval, &_v, len) != 0)        \
1625                         return -EFAULT;                         \
1626                                                                 \
1627         } while (0)
1628
1629         err = 0;
1630         sk = sock->sk;
1631         vsk = vsock_sk(sk);
1632
1633         switch (optname) {
1634         case SO_VM_SOCKETS_BUFFER_SIZE:
1635                 val = vsk->buffer_size;
1636                 COPY_OUT(val);
1637                 break;
1638
1639         case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1640                 val = vsk->buffer_max_size;
1641                 COPY_OUT(val);
1642                 break;
1643
1644         case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1645                 val = vsk->buffer_min_size;
1646                 COPY_OUT(val);
1647                 break;
1648
1649         case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1650                 struct __kernel_old_timeval tv;
1651                 tv.tv_sec = vsk->connect_timeout / HZ;
1652                 tv.tv_usec =
1653                     (vsk->connect_timeout -
1654                      tv.tv_sec * HZ) * (1000000 / HZ);
1655                 COPY_OUT(tv);
1656                 break;
1657         }
1658         default:
1659                 return -ENOPROTOOPT;
1660         }
1661
1662         err = put_user(len, optlen);
1663         if (err != 0)
1664                 return -EFAULT;
1665
1666 #undef COPY_OUT
1667
1668         return 0;
1669 }
1670
1671 static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
1672                                 size_t len)
1673 {
1674         struct sock *sk;
1675         struct vsock_sock *vsk;
1676         const struct vsock_transport *transport;
1677         ssize_t total_written;
1678         long timeout;
1679         int err;
1680         struct vsock_transport_send_notify_data send_data;
1681         DEFINE_WAIT_FUNC(wait, woken_wake_function);
1682
1683         sk = sock->sk;
1684         vsk = vsock_sk(sk);
1685         transport = vsk->transport;
1686         total_written = 0;
1687         err = 0;
1688
1689         if (msg->msg_flags & MSG_OOB)
1690                 return -EOPNOTSUPP;
1691
1692         lock_sock(sk);
1693
1694         /* Callers should not provide a destination with stream sockets. */
1695         if (msg->msg_namelen) {
1696                 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP;
1697                 goto out;
1698         }
1699
1700         /* Send data only if both sides are not shutdown in the direction. */
1701         if (sk->sk_shutdown & SEND_SHUTDOWN ||
1702             vsk->peer_shutdown & RCV_SHUTDOWN) {
1703                 err = -EPIPE;
1704                 goto out;
1705         }
1706
1707         if (!transport || sk->sk_state != TCP_ESTABLISHED ||
1708             !vsock_addr_bound(&vsk->local_addr)) {
1709                 err = -ENOTCONN;
1710                 goto out;
1711         }
1712
1713         if (!vsock_addr_bound(&vsk->remote_addr)) {
1714                 err = -EDESTADDRREQ;
1715                 goto out;
1716         }
1717
1718         /* Wait for room in the produce queue to enqueue our user's data. */
1719         timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1720
1721         err = transport->notify_send_init(vsk, &send_data);
1722         if (err < 0)
1723                 goto out;
1724
1725         while (total_written < len) {
1726                 ssize_t written;
1727
1728                 add_wait_queue(sk_sleep(sk), &wait);
1729                 while (vsock_stream_has_space(vsk) == 0 &&
1730                        sk->sk_err == 0 &&
1731                        !(sk->sk_shutdown & SEND_SHUTDOWN) &&
1732                        !(vsk->peer_shutdown & RCV_SHUTDOWN)) {
1733
1734                         /* Don't wait for non-blocking sockets. */
1735                         if (timeout == 0) {
1736                                 err = -EAGAIN;
1737                                 remove_wait_queue(sk_sleep(sk), &wait);
1738                                 goto out_err;
1739                         }
1740
1741                         err = transport->notify_send_pre_block(vsk, &send_data);
1742                         if (err < 0) {
1743                                 remove_wait_queue(sk_sleep(sk), &wait);
1744                                 goto out_err;
1745                         }
1746
1747                         release_sock(sk);
1748                         timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout);
1749                         lock_sock(sk);
1750                         if (signal_pending(current)) {
1751                                 err = sock_intr_errno(timeout);
1752                                 remove_wait_queue(sk_sleep(sk), &wait);
1753                                 goto out_err;
1754                         } else if (timeout == 0) {
1755                                 err = -EAGAIN;
1756                                 remove_wait_queue(sk_sleep(sk), &wait);
1757                                 goto out_err;
1758                         }
1759                 }
1760                 remove_wait_queue(sk_sleep(sk), &wait);
1761
1762                 /* These checks occur both as part of and after the loop
1763                  * conditional since we need to check before and after
1764                  * sleeping.
1765                  */
1766                 if (sk->sk_err) {
1767                         err = -sk->sk_err;
1768                         goto out_err;
1769                 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) ||
1770                            (vsk->peer_shutdown & RCV_SHUTDOWN)) {
1771                         err = -EPIPE;
1772                         goto out_err;
1773                 }
1774
1775                 err = transport->notify_send_pre_enqueue(vsk, &send_data);
1776                 if (err < 0)
1777                         goto out_err;
1778
1779                 /* Note that enqueue will only write as many bytes as are free
1780                  * in the produce queue, so we don't need to ensure len is
1781                  * smaller than the queue size.  It is the caller's
1782                  * responsibility to check how many bytes we were able to send.
1783                  */
1784
1785                 written = transport->stream_enqueue(
1786                                 vsk, msg,
1787                                 len - total_written);
1788                 if (written < 0) {
1789                         err = -ENOMEM;
1790                         goto out_err;
1791                 }
1792
1793                 total_written += written;
1794
1795                 err = transport->notify_send_post_enqueue(
1796                                 vsk, written, &send_data);
1797                 if (err < 0)
1798                         goto out_err;
1799
1800         }
1801
1802 out_err:
1803         if (total_written > 0)
1804                 err = total_written;
1805 out:
1806         release_sock(sk);
1807         return err;
1808 }
1809
1810
1811 static int
1812 vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1813                      int flags)
1814 {
1815         struct sock *sk;
1816         struct vsock_sock *vsk;
1817         const struct vsock_transport *transport;
1818         int err;
1819         size_t target;
1820         ssize_t copied;
1821         long timeout;
1822         struct vsock_transport_recv_notify_data recv_data;
1823
1824         DEFINE_WAIT(wait);
1825
1826         sk = sock->sk;
1827         vsk = vsock_sk(sk);
1828         transport = vsk->transport;
1829         err = 0;
1830
1831         lock_sock(sk);
1832
1833         if (!transport || sk->sk_state != TCP_ESTABLISHED) {
1834                 /* Recvmsg is supposed to return 0 if a peer performs an
1835                  * orderly shutdown. Differentiate between that case and when a
1836                  * peer has not connected or a local shutdown occured with the
1837                  * SOCK_DONE flag.
1838                  */
1839                 if (sock_flag(sk, SOCK_DONE))
1840                         err = 0;
1841                 else
1842                         err = -ENOTCONN;
1843
1844                 goto out;
1845         }
1846
1847         if (flags & MSG_OOB) {
1848                 err = -EOPNOTSUPP;
1849                 goto out;
1850         }
1851
1852         /* We don't check peer_shutdown flag here since peer may actually shut
1853          * down, but there can be data in the queue that a local socket can
1854          * receive.
1855          */
1856         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1857                 err = 0;
1858                 goto out;
1859         }
1860
1861         /* It is valid on Linux to pass in a zero-length receive buffer.  This
1862          * is not an error.  We may as well bail out now.
1863          */
1864         if (!len) {
1865                 err = 0;
1866                 goto out;
1867         }
1868
1869         /* We must not copy less than target bytes into the user's buffer
1870          * before returning successfully, so we wait for the consume queue to
1871          * have that much data to consume before dequeueing.  Note that this
1872          * makes it impossible to handle cases where target is greater than the
1873          * queue size.
1874          */
1875         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1876         if (target >= transport->stream_rcvhiwat(vsk)) {
1877                 err = -ENOMEM;
1878                 goto out;
1879         }
1880         timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1881         copied = 0;
1882
1883         err = transport->notify_recv_init(vsk, target, &recv_data);
1884         if (err < 0)
1885                 goto out;
1886
1887
1888         while (1) {
1889                 s64 ready;
1890
1891                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1892                 ready = vsock_stream_has_data(vsk);
1893
1894                 if (ready == 0) {
1895                         if (sk->sk_err != 0 ||
1896                             (sk->sk_shutdown & RCV_SHUTDOWN) ||
1897                             (vsk->peer_shutdown & SEND_SHUTDOWN)) {
1898                                 finish_wait(sk_sleep(sk), &wait);
1899                                 break;
1900                         }
1901                         /* Don't wait for non-blocking sockets. */
1902                         if (timeout == 0) {
1903                                 err = -EAGAIN;
1904                                 finish_wait(sk_sleep(sk), &wait);
1905                                 break;
1906                         }
1907
1908                         err = transport->notify_recv_pre_block(
1909                                         vsk, target, &recv_data);
1910                         if (err < 0) {
1911                                 finish_wait(sk_sleep(sk), &wait);
1912                                 break;
1913                         }
1914                         release_sock(sk);
1915                         timeout = schedule_timeout(timeout);
1916                         lock_sock(sk);
1917
1918                         if (signal_pending(current)) {
1919                                 err = sock_intr_errno(timeout);
1920                                 finish_wait(sk_sleep(sk), &wait);
1921                                 break;
1922                         } else if (timeout == 0) {
1923                                 err = -EAGAIN;
1924                                 finish_wait(sk_sleep(sk), &wait);
1925                                 break;
1926                         }
1927                 } else {
1928                         ssize_t read;
1929
1930                         finish_wait(sk_sleep(sk), &wait);
1931
1932                         if (ready < 0) {
1933                                 /* Invalid queue pair content. XXX This should
1934                                 * be changed to a connection reset in a later
1935                                 * change.
1936                                 */
1937
1938                                 err = -ENOMEM;
1939                                 goto out;
1940                         }
1941
1942                         err = transport->notify_recv_pre_dequeue(
1943                                         vsk, target, &recv_data);
1944                         if (err < 0)
1945                                 break;
1946
1947                         read = transport->stream_dequeue(
1948                                         vsk, msg,
1949                                         len - copied, flags);
1950                         if (read < 0) {
1951                                 err = -ENOMEM;
1952                                 break;
1953                         }
1954
1955                         copied += read;
1956
1957                         err = transport->notify_recv_post_dequeue(
1958                                         vsk, target, read,
1959                                         !(flags & MSG_PEEK), &recv_data);
1960                         if (err < 0)
1961                                 goto out;
1962
1963                         if (read >= target || flags & MSG_PEEK)
1964                                 break;
1965
1966                         target -= read;
1967                 }
1968         }
1969
1970         if (sk->sk_err)
1971                 err = -sk->sk_err;
1972         else if (sk->sk_shutdown & RCV_SHUTDOWN)
1973                 err = 0;
1974
1975         if (copied > 0)
1976                 err = copied;
1977
1978 out:
1979         release_sock(sk);
1980         return err;
1981 }
1982
1983 static const struct proto_ops vsock_stream_ops = {
1984         .family = PF_VSOCK,
1985         .owner = THIS_MODULE,
1986         .release = vsock_release,
1987         .bind = vsock_bind,
1988         .connect = vsock_stream_connect,
1989         .socketpair = sock_no_socketpair,
1990         .accept = vsock_accept,
1991         .getname = vsock_getname,
1992         .poll = vsock_poll,
1993         .ioctl = sock_no_ioctl,
1994         .listen = vsock_listen,
1995         .shutdown = vsock_shutdown,
1996         .setsockopt = vsock_stream_setsockopt,
1997         .getsockopt = vsock_stream_getsockopt,
1998         .sendmsg = vsock_stream_sendmsg,
1999         .recvmsg = vsock_stream_recvmsg,
2000         .mmap = sock_no_mmap,
2001         .sendpage = sock_no_sendpage,
2002 };
2003
2004 static int vsock_create(struct net *net, struct socket *sock,
2005                         int protocol, int kern)
2006 {
2007         struct vsock_sock *vsk;
2008         struct sock *sk;
2009         int ret;
2010
2011         if (!sock)
2012                 return -EINVAL;
2013
2014         if (protocol && protocol != PF_VSOCK)
2015                 return -EPROTONOSUPPORT;
2016
2017         switch (sock->type) {
2018         case SOCK_DGRAM:
2019                 sock->ops = &vsock_dgram_ops;
2020                 break;
2021         case SOCK_STREAM:
2022                 sock->ops = &vsock_stream_ops;
2023                 break;
2024         default:
2025                 return -ESOCKTNOSUPPORT;
2026         }
2027
2028         sock->state = SS_UNCONNECTED;
2029
2030         sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern);
2031         if (!sk)
2032                 return -ENOMEM;
2033
2034         vsk = vsock_sk(sk);
2035
2036         if (sock->type == SOCK_DGRAM) {
2037                 ret = vsock_assign_transport(vsk, NULL);
2038                 if (ret < 0) {
2039                         sock_put(sk);
2040                         return ret;
2041                 }
2042         }
2043
2044         vsock_insert_unbound(vsk);
2045
2046         return 0;
2047 }
2048
2049 static const struct net_proto_family vsock_family_ops = {
2050         .family = AF_VSOCK,
2051         .create = vsock_create,
2052         .owner = THIS_MODULE,
2053 };
2054
2055 static long vsock_dev_do_ioctl(struct file *filp,
2056                                unsigned int cmd, void __user *ptr)
2057 {
2058         u32 __user *p = ptr;
2059         u32 cid = VMADDR_CID_ANY;
2060         int retval = 0;
2061
2062         switch (cmd) {
2063         case IOCTL_VM_SOCKETS_GET_LOCAL_CID:
2064                 /* To be compatible with the VMCI behavior, we prioritize the
2065                  * guest CID instead of well-know host CID (VMADDR_CID_HOST).
2066                  */
2067                 if (transport_g2h)
2068                         cid = transport_g2h->get_local_cid();
2069                 else if (transport_h2g)
2070                         cid = transport_h2g->get_local_cid();
2071
2072                 if (put_user(cid, p) != 0)
2073                         retval = -EFAULT;
2074                 break;
2075
2076         default:
2077                 pr_err("Unknown ioctl %d\n", cmd);
2078                 retval = -EINVAL;
2079         }
2080
2081         return retval;
2082 }
2083
2084 static long vsock_dev_ioctl(struct file *filp,
2085                             unsigned int cmd, unsigned long arg)
2086 {
2087         return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg);
2088 }
2089
2090 #ifdef CONFIG_COMPAT
2091 static long vsock_dev_compat_ioctl(struct file *filp,
2092                                    unsigned int cmd, unsigned long arg)
2093 {
2094         return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg));
2095 }
2096 #endif
2097
2098 static const struct file_operations vsock_device_ops = {
2099         .owner          = THIS_MODULE,
2100         .unlocked_ioctl = vsock_dev_ioctl,
2101 #ifdef CONFIG_COMPAT
2102         .compat_ioctl   = vsock_dev_compat_ioctl,
2103 #endif
2104         .open           = nonseekable_open,
2105 };
2106
2107 static struct miscdevice vsock_device = {
2108         .name           = "vsock",
2109         .fops           = &vsock_device_ops,
2110 };
2111
2112 static int __init vsock_init(void)
2113 {
2114         int err = 0;
2115
2116         vsock_init_tables();
2117
2118         vsock_proto.owner = THIS_MODULE;
2119         vsock_device.minor = MISC_DYNAMIC_MINOR;
2120         err = misc_register(&vsock_device);
2121         if (err) {
2122                 pr_err("Failed to register misc device\n");
2123                 goto err_reset_transport;
2124         }
2125
2126         err = proto_register(&vsock_proto, 1);  /* we want our slab */
2127         if (err) {
2128                 pr_err("Cannot register vsock protocol\n");
2129                 goto err_deregister_misc;
2130         }
2131
2132         err = sock_register(&vsock_family_ops);
2133         if (err) {
2134                 pr_err("could not register af_vsock (%d) address family: %d\n",
2135                        AF_VSOCK, err);
2136                 goto err_unregister_proto;
2137         }
2138
2139         return 0;
2140
2141 err_unregister_proto:
2142         proto_unregister(&vsock_proto);
2143 err_deregister_misc:
2144         misc_deregister(&vsock_device);
2145 err_reset_transport:
2146         return err;
2147 }
2148
2149 static void __exit vsock_exit(void)
2150 {
2151         misc_deregister(&vsock_device);
2152         sock_unregister(AF_VSOCK);
2153         proto_unregister(&vsock_proto);
2154 }
2155
2156 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk)
2157 {
2158         return vsk->transport;
2159 }
2160 EXPORT_SYMBOL_GPL(vsock_core_get_transport);
2161
2162 int vsock_core_register(const struct vsock_transport *t, int features)
2163 {
2164         const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local;
2165         int err = mutex_lock_interruptible(&vsock_register_mutex);
2166
2167         if (err)
2168                 return err;
2169
2170         t_h2g = transport_h2g;
2171         t_g2h = transport_g2h;
2172         t_dgram = transport_dgram;
2173         t_local = transport_local;
2174
2175         if (features & VSOCK_TRANSPORT_F_H2G) {
2176                 if (t_h2g) {
2177                         err = -EBUSY;
2178                         goto err_busy;
2179                 }
2180                 t_h2g = t;
2181         }
2182
2183         if (features & VSOCK_TRANSPORT_F_G2H) {
2184                 if (t_g2h) {
2185                         err = -EBUSY;
2186                         goto err_busy;
2187                 }
2188                 t_g2h = t;
2189         }
2190
2191         if (features & VSOCK_TRANSPORT_F_DGRAM) {
2192                 if (t_dgram) {
2193                         err = -EBUSY;
2194                         goto err_busy;
2195                 }
2196                 t_dgram = t;
2197         }
2198
2199         if (features & VSOCK_TRANSPORT_F_LOCAL) {
2200                 if (t_local) {
2201                         err = -EBUSY;
2202                         goto err_busy;
2203                 }
2204                 t_local = t;
2205         }
2206
2207         transport_h2g = t_h2g;
2208         transport_g2h = t_g2h;
2209         transport_dgram = t_dgram;
2210         transport_local = t_local;
2211
2212 err_busy:
2213         mutex_unlock(&vsock_register_mutex);
2214         return err;
2215 }
2216 EXPORT_SYMBOL_GPL(vsock_core_register);
2217
2218 void vsock_core_unregister(const struct vsock_transport *t)
2219 {
2220         mutex_lock(&vsock_register_mutex);
2221
2222         if (transport_h2g == t)
2223                 transport_h2g = NULL;
2224
2225         if (transport_g2h == t)
2226                 transport_g2h = NULL;
2227
2228         if (transport_dgram == t)
2229                 transport_dgram = NULL;
2230
2231         if (transport_local == t)
2232                 transport_local = NULL;
2233
2234         mutex_unlock(&vsock_register_mutex);
2235 }
2236 EXPORT_SYMBOL_GPL(vsock_core_unregister);
2237
2238 module_init(vsock_init);
2239 module_exit(vsock_exit);
2240
2241 MODULE_AUTHOR("VMware, Inc.");
2242 MODULE_DESCRIPTION("VMware Virtual Socket Family");
2243 MODULE_VERSION("1.0.2.0-k");
2244 MODULE_LICENSE("GPL v2");