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                 vsk->transport->release(vsk);
 455                 vsock_deassign_transport(vsk);
 456         }
 457
 458         /* We increase the module refcnt to prevent the transport unloading
 459          * while there are open sockets assigned to it.
 460          */
 461         if (!new_transport || !try_module_get(new_transport->module))
 462                 return -ENODEV;
 463
 464         ret = new_transport->init(vsk, psk);
 465         if (ret) {
 466                 module_put(new_transport->module);
 467                 return ret;
 468         }
 469
 470         vsk->transport = new_transport;
 471
 472         return 0;
 473 }
 474 EXPORT_SYMBOL_GPL(vsock_assign_transport);
 475
 476 bool vsock_find_cid(unsigned int cid)
 477 {
 478         if (transport_g2h && cid == transport_g2h->get_local_cid())
 479                 return true;
 480
 481         if (transport_h2g && cid == VMADDR_CID_HOST)
 482                 return true;
 483
 484         if (transport_local && cid == VMADDR_CID_LOCAL)
 485                 return true;
 486
 487         return false;
 488 }
 489 EXPORT_SYMBOL_GPL(vsock_find_cid);
 490
 491 static struct sock *vsock_dequeue_accept(struct sock *listener)
 492 {
 493         struct vsock_sock *vlistener;
 494         struct vsock_sock *vconnected;
 495
 496         vlistener = vsock_sk(listener);
 497
 498         if (list_empty(&vlistener->accept_queue))
 499                 return NULL;
 500
 501         vconnected = list_entry(vlistener->accept_queue.next,
 502                                 struct vsock_sock, accept_queue);
 503
 504         list_del_init(&vconnected->accept_queue);
 505         sock_put(listener);
 506         /* The caller will need a reference on the connected socket so we let
 507          * it call sock_put().
 508          */
 509
 510         return sk_vsock(vconnected);
 511 }
 512
 513 static bool vsock_is_accept_queue_empty(struct sock *sk)
 514 {
 515         struct vsock_sock *vsk = vsock_sk(sk);
 516         return list_empty(&vsk->accept_queue);
 517 }
 518
 519 static bool vsock_is_pending(struct sock *sk)
 520 {
 521         struct vsock_sock *vsk = vsock_sk(sk);
 522         return !list_empty(&vsk->pending_links);
 523 }
 524
 525 static int vsock_send_shutdown(struct sock *sk, int mode)
 526 {
 527         struct vsock_sock *vsk = vsock_sk(sk);
 528
 529         if (!vsk->transport)
 530                 return -ENODEV;
 531
 532         return vsk->transport->shutdown(vsk, mode);
 533 }
 534
 535 static void vsock_pending_work(struct work_struct *work)
 536 {
 537         struct sock *sk;
 538         struct sock *listener;
 539         struct vsock_sock *vsk;
 540         bool cleanup;
 541
 542         vsk = container_of(work, struct vsock_sock, pending_work.work);
 543         sk = sk_vsock(vsk);
 544         listener = vsk->listener;
 545         cleanup = true;
 546
 547         lock_sock(listener);
 548         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 549
 550         if (vsock_is_pending(sk)) {
 551                 vsock_remove_pending(listener, sk);
 552
 553                 sk_acceptq_removed(listener);
 554         } else if (!vsk->rejected) {
 555                 /* We are not on the pending list and accept() did not reject
 556                  * us, so we must have been accepted by our user process.  We
 557                  * just need to drop our references to the sockets and be on
 558                  * our way.
 559                  */
 560                 cleanup = false;
 561                 goto out;
 562         }
 563
 564         /* We need to remove ourself from the global connected sockets list so
 565          * incoming packets can't find this socket, and to reduce the reference
 566          * count.
 567          */
 568         vsock_remove_connected(vsk);
 569
 570         sk->sk_state = TCP_CLOSE;
 571
 572 out:
 573         release_sock(sk);
 574         release_sock(listener);
 575         if (cleanup)
 576                 sock_put(sk);
 577
 578         sock_put(sk);
 579         sock_put(listener);
 580 }
 581
 582 /**** SOCKET OPERATIONS ****/
 583
 584 static int __vsock_bind_stream(struct vsock_sock *vsk,
 585                                struct sockaddr_vm *addr)
 586 {
 587         static u32 port;
 588         struct sockaddr_vm new_addr;
 589
 590         if (!port)
 591                 port = LAST_RESERVED_PORT + 1 +
 592                         prandom_u32_max(U32_MAX - LAST_RESERVED_PORT);
 593
 594         vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port);
 595
 596         if (addr->svm_port == VMADDR_PORT_ANY) {
 597                 bool found = false;
 598                 unsigned int i;
 599
 600                 for (i = 0; i < MAX_PORT_RETRIES; i++) {
 601                         if (port <= LAST_RESERVED_PORT)
 602                                 port = LAST_RESERVED_PORT + 1;
 603
 604                         new_addr.svm_port = port++;
 605
 606                         if (!__vsock_find_bound_socket(&new_addr)) {
 607                                 found = true;
 608                                 break;
 609                         }
 610                 }
 611
 612                 if (!found)
 613                         return -EADDRNOTAVAIL;
 614         } else {
 615                 /* If port is in reserved range, ensure caller
 616                  * has necessary privileges.
 617                  */
 618                 if (addr->svm_port <= LAST_RESERVED_PORT &&
 619                     !capable(CAP_NET_BIND_SERVICE)) {
 620                         return -EACCES;
 621                 }
 622
 623                 if (__vsock_find_bound_socket(&new_addr))
 624                         return -EADDRINUSE;
 625         }
 626
 627         vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port);
 628
 629         /* Remove stream sockets from the unbound list and add them to the hash
 630          * table for easy lookup by its address.  The unbound list is simply an
 631          * extra entry at the end of the hash table, a trick used by AF_UNIX.
 632          */
 633         __vsock_remove_bound(vsk);
 634         __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk);
 635
 636         return 0;
 637 }
 638
 639 static int __vsock_bind_dgram(struct vsock_sock *vsk,
 640                               struct sockaddr_vm *addr)
 641 {
 642         return vsk->transport->dgram_bind(vsk, addr);
 643 }
 644
 645 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr)
 646 {
 647         struct vsock_sock *vsk = vsock_sk(sk);
 648         int retval;
 649
 650         /* First ensure this socket isn't already bound. */
 651         if (vsock_addr_bound(&vsk->local_addr))
 652                 return -EINVAL;
 653
 654         /* Now bind to the provided address or select appropriate values if
 655          * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY).  Note that
 656          * like AF_INET prevents binding to a non-local IP address (in most
 657          * cases), we only allow binding to a local CID.
 658          */
 659         if (addr->svm_cid != VMADDR_CID_ANY && !vsock_find_cid(addr->svm_cid))
 660                 return -EADDRNOTAVAIL;
 661
 662         switch (sk->sk_socket->type) {
 663         case SOCK_STREAM:
 664                 spin_lock_bh(&vsock_table_lock);
 665                 retval = __vsock_bind_stream(vsk, addr);
 666                 spin_unlock_bh(&vsock_table_lock);
 667                 break;
 668
 669         case SOCK_DGRAM:
 670                 retval = __vsock_bind_dgram(vsk, addr);
 671                 break;
 672
 673         default:
 674                 retval = -EINVAL;
 675                 break;
 676         }
 677
 678         return retval;
 679 }
 680
 681 static void vsock_connect_timeout(struct work_struct *work);
 682
 683 static struct sock *__vsock_create(struct net *net,
 684                                    struct socket *sock,
 685                                    struct sock *parent,
 686                                    gfp_t priority,
 687                                    unsigned short type,
 688                                    int kern)
 689 {
 690         struct sock *sk;
 691         struct vsock_sock *psk;
 692         struct vsock_sock *vsk;
 693
 694         sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto, kern);
 695         if (!sk)
 696                 return NULL;
 697
 698         sock_init_data(sock, sk);
 699
 700         /* sk->sk_type is normally set in sock_init_data, but only if sock is
 701          * non-NULL. We make sure that our sockets always have a type by
 702          * setting it here if needed.
 703          */
 704         if (!sock)
 705                 sk->sk_type = type;
 706
 707         vsk = vsock_sk(sk);
 708         vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 709         vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 710
 711         sk->sk_destruct = vsock_sk_destruct;
 712         sk->sk_backlog_rcv = vsock_queue_rcv_skb;
 713         sock_reset_flag(sk, SOCK_DONE);
 714
 715         INIT_LIST_HEAD(&vsk->bound_table);
 716         INIT_LIST_HEAD(&vsk->connected_table);
 717         vsk->listener = NULL;
 718         INIT_LIST_HEAD(&vsk->pending_links);
 719         INIT_LIST_HEAD(&vsk->accept_queue);
 720         vsk->rejected = false;
 721         vsk->sent_request = false;
 722         vsk->ignore_connecting_rst = false;
 723         vsk->peer_shutdown = 0;
 724         INIT_DELAYED_WORK(&vsk->connect_work, vsock_connect_timeout);
 725         INIT_DELAYED_WORK(&vsk->pending_work, vsock_pending_work);
 726
 727         psk = parent ? vsock_sk(parent) : NULL;
 728         if (parent) {
 729                 vsk->trusted = psk->trusted;
 730                 vsk->owner = get_cred(psk->owner);
 731                 vsk->connect_timeout = psk->connect_timeout;
 732                 vsk->buffer_size = psk->buffer_size;
 733                 vsk->buffer_min_size = psk->buffer_min_size;
 734                 vsk->buffer_max_size = psk->buffer_max_size;
 735         } else {
 736                 vsk->trusted = capable(CAP_NET_ADMIN);
 737                 vsk->owner = get_current_cred();
 738                 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT;
 739                 vsk->buffer_size = VSOCK_DEFAULT_BUFFER_SIZE;
 740                 vsk->buffer_min_size = VSOCK_DEFAULT_BUFFER_MIN_SIZE;
 741                 vsk->buffer_max_size = VSOCK_DEFAULT_BUFFER_MAX_SIZE;
 742         }
 743
 744         return sk;
 745 }
 746
 747 static void __vsock_release(struct sock *sk, int level)
 748 {
 749         if (sk) {
 750                 struct sock *pending;
 751                 struct vsock_sock *vsk;
 752
 753                 vsk = vsock_sk(sk);
 754                 pending = NULL; /* Compiler warning. */
 755
 756                 /* The release call is supposed to use lock_sock_nested()
 757                  * rather than lock_sock(), if a sock lock should be acquired.
 758                  */
 759                 if (vsk->transport)
 760                         vsk->transport->release(vsk);
 761                 else if (sk->sk_type == SOCK_STREAM)
 762                         vsock_remove_sock(vsk);
 763
 764                 /* When "level" is SINGLE_DEPTH_NESTING, use the nested
 765                  * version to avoid the warning "possible recursive locking
 766                  * detected". When "level" is 0, lock_sock_nested(sk, level)
 767                  * is the same as lock_sock(sk).
 768                  */
 769                 lock_sock_nested(sk, level);
 770                 sock_orphan(sk);
 771                 sk->sk_shutdown = SHUTDOWN_MASK;
 772
 773                 skb_queue_purge(&sk->sk_receive_queue);
 774
 775                 /* Clean up any sockets that never were accepted. */
 776                 while ((pending = vsock_dequeue_accept(sk)) != NULL) {
 777                         __vsock_release(pending, SINGLE_DEPTH_NESTING);
 778                         sock_put(pending);
 779                 }
 780
 781                 release_sock(sk);
 782                 sock_put(sk);
 783         }
 784 }
 785
 786 static void vsock_sk_destruct(struct sock *sk)
 787 {
 788         struct vsock_sock *vsk = vsock_sk(sk);
 789
 790         vsock_deassign_transport(vsk);
 791
 792         /* When clearing these addresses, there's no need to set the family and
 793          * possibly register the address family with the kernel.
 794          */
 795         vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 796         vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 797
 798         put_cred(vsk->owner);
 799 }
 800
 801 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 802 {
 803         int err;
 804
 805         err = sock_queue_rcv_skb(sk, skb);
 806         if (err)
 807                 kfree_skb(skb);
 808
 809         return err;
 810 }
 811
 812 struct sock *vsock_create_connected(struct sock *parent)
 813 {
 814         return __vsock_create(sock_net(parent), NULL, parent, GFP_KERNEL,
 815                               parent->sk_type, 0);
 816 }
 817 EXPORT_SYMBOL_GPL(vsock_create_connected);
 818
 819 s64 vsock_stream_has_data(struct vsock_sock *vsk)
 820 {
 821         return vsk->transport->stream_has_data(vsk);
 822 }
 823 EXPORT_SYMBOL_GPL(vsock_stream_has_data);
 824
 825 s64 vsock_stream_has_space(struct vsock_sock *vsk)
 826 {
 827         return vsk->transport->stream_has_space(vsk);
 828 }
 829 EXPORT_SYMBOL_GPL(vsock_stream_has_space);
 830
 831 static int vsock_release(struct socket *sock)
 832 {
 833         __vsock_release(sock->sk, 0);
 834         sock->sk = NULL;
 835         sock->state = SS_FREE;
 836
 837         return 0;
 838 }
 839
 840 static int
 841 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
 842 {
 843         int err;
 844         struct sock *sk;
 845         struct sockaddr_vm *vm_addr;
 846
 847         sk = sock->sk;
 848
 849         if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0)
 850                 return -EINVAL;
 851
 852         lock_sock(sk);
 853         err = __vsock_bind(sk, vm_addr);
 854         release_sock(sk);
 855
 856         return err;
 857 }
 858
 859 static int vsock_getname(struct socket *sock,
 860                          struct sockaddr *addr, int peer)
 861 {
 862         int err;
 863         struct sock *sk;
 864         struct vsock_sock *vsk;
 865         struct sockaddr_vm *vm_addr;
 866
 867         sk = sock->sk;
 868         vsk = vsock_sk(sk);
 869         err = 0;
 870
 871         lock_sock(sk);
 872
 873         if (peer) {
 874                 if (sock->state != SS_CONNECTED) {
 875                         err = -ENOTCONN;
 876                         goto out;
 877                 }
 878                 vm_addr = &vsk->remote_addr;
 879         } else {
 880                 vm_addr = &vsk->local_addr;
 881         }
 882
 883         if (!vm_addr) {
 884                 err = -EINVAL;
 885                 goto out;
 886         }
 887
 888         /* sys_getsockname() and sys_getpeername() pass us a
 889          * MAX_SOCK_ADDR-sized buffer and don't set addr_len.  Unfortunately
 890          * that macro is defined in socket.c instead of .h, so we hardcode its
 891          * value here.
 892          */
 893         BUILD_BUG_ON(sizeof(*vm_addr) > 128);
 894         memcpy(addr, vm_addr, sizeof(*vm_addr));
 895         err = sizeof(*vm_addr);
 896
 897 out:
 898         release_sock(sk);
 899         return err;
 900 }
 901
 902 static int vsock_shutdown(struct socket *sock, int mode)
 903 {
 904         int err;
 905         struct sock *sk;
 906
 907         /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses
 908          * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode
 909          * here like the other address families do.  Note also that the
 910          * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3),
 911          * which is what we want.
 912          */
 913         mode++;
 914
 915         if ((mode & ~SHUTDOWN_MASK) || !mode)
 916                 return -EINVAL;
 917
 918         /* If this is a STREAM socket and it is not connected then bail out
 919          * immediately.  If it is a DGRAM socket then we must first kick the
 920          * socket so that it wakes up from any sleeping calls, for example
 921          * recv(), and then afterwards return the error.
 922          */
 923
 924         sk = sock->sk;
 925         if (sock->state == SS_UNCONNECTED) {
 926                 err = -ENOTCONN;
 927                 if (sk->sk_type == SOCK_STREAM)
 928                         return err;
 929         } else {
 930                 sock->state = SS_DISCONNECTING;
 931                 err = 0;
 932         }
 933
 934         /* Receive and send shutdowns are treated alike. */
 935         mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN);
 936         if (mode) {
 937                 lock_sock(sk);
 938                 sk->sk_shutdown |= mode;
 939                 sk->sk_state_change(sk);
 940                 release_sock(sk);
 941
 942                 if (sk->sk_type == SOCK_STREAM) {
 943                         sock_reset_flag(sk, SOCK_DONE);
 944                         vsock_send_shutdown(sk, mode);
 945                 }
 946         }
 947
 948         return err;
 949 }
 950
 951 static __poll_t vsock_poll(struct file *file, struct socket *sock,
 952                                poll_table *wait)
 953 {
 954         struct sock *sk;
 955         __poll_t mask;
 956         struct vsock_sock *vsk;
 957
 958         sk = sock->sk;
 959         vsk = vsock_sk(sk);
 960
 961         poll_wait(file, sk_sleep(sk), wait);
 962         mask = 0;
 963
 964         if (sk->sk_err)
 965                 /* Signify that there has been an error on this socket. */
 966                 mask |= EPOLLERR;
 967
 968         /* INET sockets treat local write shutdown and peer write shutdown as a
 969          * case of EPOLLHUP set.
 970          */
 971         if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
 972             ((sk->sk_shutdown & SEND_SHUTDOWN) &&
 973              (vsk->peer_shutdown & SEND_SHUTDOWN))) {
 974                 mask |= EPOLLHUP;
 975         }
 976
 977         if (sk->sk_shutdown & RCV_SHUTDOWN ||
 978             vsk->peer_shutdown & SEND_SHUTDOWN) {
 979                 mask |= EPOLLRDHUP;
 980         }
 981
 982         if (sock->type == SOCK_DGRAM) {
 983                 /* For datagram sockets we can read if there is something in
 984                  * the queue and write as long as the socket isn't shutdown for
 985                  * sending.
 986                  */
 987                 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) ||
 988                     (sk->sk_shutdown & RCV_SHUTDOWN)) {
 989                         mask |= EPOLLIN | EPOLLRDNORM;
 990                 }
 991
 992                 if (!(sk->sk_shutdown & SEND_SHUTDOWN))
 993                         mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
 994
 995         } else if (sock->type == SOCK_STREAM) {
 996                 const struct vsock_transport *transport = vsk->transport;
 997                 lock_sock(sk);
 998
 999                 /* Listening sockets that have connections in their accept
1000                  * queue can be read.
1001                  */
1002                 if (sk->sk_state == TCP_LISTEN
1003                     && !vsock_is_accept_queue_empty(sk))
1004                         mask |= EPOLLIN | EPOLLRDNORM;
1005
1006                 /* If there is something in the queue then we can read. */
1007                 if (transport && transport->stream_is_active(vsk) &&
1008                     !(sk->sk_shutdown & RCV_SHUTDOWN)) {
1009                         bool data_ready_now = false;
1010                         int ret = transport->notify_poll_in(
1011                                         vsk, 1, &data_ready_now);
1012                         if (ret < 0) {
1013                                 mask |= EPOLLERR;
1014                         } else {
1015                                 if (data_ready_now)
1016                                         mask |= EPOLLIN | EPOLLRDNORM;
1017
1018                         }
1019                 }
1020
1021                 /* Sockets whose connections have been closed, reset, or
1022                  * terminated should also be considered read, and we check the
1023                  * shutdown flag for that.
1024                  */
1025                 if (sk->sk_shutdown & RCV_SHUTDOWN ||
1026                     vsk->peer_shutdown & SEND_SHUTDOWN) {
1027                         mask |= EPOLLIN | EPOLLRDNORM;
1028                 }
1029
1030                 /* Connected sockets that can produce data can be written. */
1031                 if (sk->sk_state == TCP_ESTABLISHED) {
1032                         if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1033                                 bool space_avail_now = false;
1034                                 int ret = transport->notify_poll_out(
1035                                                 vsk, 1, &space_avail_now);
1036                                 if (ret < 0) {
1037                                         mask |= EPOLLERR;
1038                                 } else {
1039                                         if (space_avail_now)
1040                                                 /* Remove EPOLLWRBAND since INET
1041                                                  * sockets are not setting it.
1042                                                  */
1043                                                 mask |= EPOLLOUT | EPOLLWRNORM;
1044
1045                                 }
1046                         }
1047                 }
1048
1049                 /* Simulate INET socket poll behaviors, which sets
1050                  * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read,
1051                  * but local send is not shutdown.
1052                  */
1053                 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) {
1054                         if (!(sk->sk_shutdown & SEND_SHUTDOWN))
1055                                 mask |= EPOLLOUT | EPOLLWRNORM;
1056
1057                 }
1058
1059                 release_sock(sk);
1060         }
1061
1062         return mask;
1063 }
1064
1065 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
1066                                size_t len)
1067 {
1068         int err;
1069         struct sock *sk;
1070         struct vsock_sock *vsk;
1071         struct sockaddr_vm *remote_addr;
1072         const struct vsock_transport *transport;
1073
1074         if (msg->msg_flags & MSG_OOB)
1075                 return -EOPNOTSUPP;
1076
1077         /* For now, MSG_DONTWAIT is always assumed... */
1078         err = 0;
1079         sk = sock->sk;
1080         vsk = vsock_sk(sk);
1081         transport = vsk->transport;
1082
1083         lock_sock(sk);
1084
1085         err = vsock_auto_bind(vsk);
1086         if (err)
1087                 goto out;
1088
1089
1090         /* If the provided message contains an address, use that.  Otherwise
1091          * fall back on the socket's remote handle (if it has been connected).
1092          */
1093         if (msg->msg_name &&
1094             vsock_addr_cast(msg->msg_name, msg->msg_namelen,
1095                             &remote_addr) == 0) {
1096                 /* Ensure this address is of the right type and is a valid
1097                  * destination.
1098                  */
1099
1100                 if (remote_addr->svm_cid == VMADDR_CID_ANY)
1101                         remote_addr->svm_cid = transport->get_local_cid();
1102
1103                 if (!vsock_addr_bound(remote_addr)) {
1104                         err = -EINVAL;
1105                         goto out;
1106                 }
1107         } else if (sock->state == SS_CONNECTED) {
1108                 remote_addr = &vsk->remote_addr;
1109
1110                 if (remote_addr->svm_cid == VMADDR_CID_ANY)
1111                         remote_addr->svm_cid = transport->get_local_cid();
1112
1113                 /* XXX Should connect() or this function ensure remote_addr is
1114                  * bound?
1115                  */
1116                 if (!vsock_addr_bound(&vsk->remote_addr)) {
1117                         err = -EINVAL;
1118                         goto out;
1119                 }
1120         } else {
1121                 err = -EINVAL;
1122                 goto out;
1123         }
1124
1125         if (!transport->dgram_allow(remote_addr->svm_cid,
1126                                     remote_addr->svm_port)) {
1127                 err = -EINVAL;
1128                 goto out;
1129         }
1130
1131         err = transport->dgram_enqueue(vsk, remote_addr, msg, len);
1132
1133 out:
1134         release_sock(sk);
1135         return err;
1136 }
1137
1138 static int vsock_dgram_connect(struct socket *sock,
1139                                struct sockaddr *addr, int addr_len, int flags)
1140 {
1141         int err;
1142         struct sock *sk;
1143         struct vsock_sock *vsk;
1144         struct sockaddr_vm *remote_addr;
1145
1146         sk = sock->sk;
1147         vsk = vsock_sk(sk);
1148
1149         err = vsock_addr_cast(addr, addr_len, &remote_addr);
1150         if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) {
1151                 lock_sock(sk);
1152                 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY,
1153                                 VMADDR_PORT_ANY);
1154                 sock->state = SS_UNCONNECTED;
1155                 release_sock(sk);
1156                 return 0;
1157         } else if (err != 0)
1158                 return -EINVAL;
1159
1160         lock_sock(sk);
1161
1162         err = vsock_auto_bind(vsk);
1163         if (err)
1164                 goto out;
1165
1166         if (!vsk->transport->dgram_allow(remote_addr->svm_cid,
1167                                          remote_addr->svm_port)) {
1168                 err = -EINVAL;
1169                 goto out;
1170         }
1171
1172         memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr));
1173         sock->state = SS_CONNECTED;
1174
1175 out:
1176         release_sock(sk);
1177         return err;
1178 }
1179
1180 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg,
1181                                size_t len, int flags)
1182 {
1183         struct vsock_sock *vsk = vsock_sk(sock->sk);
1184
1185         return vsk->transport->dgram_dequeue(vsk, msg, len, flags);
1186 }
1187
1188 static const struct proto_ops vsock_dgram_ops = {
1189         .family = PF_VSOCK,
1190         .owner = THIS_MODULE,
1191         .release = vsock_release,
1192         .bind = vsock_bind,
1193         .connect = vsock_dgram_connect,
1194         .socketpair = sock_no_socketpair,
1195         .accept = sock_no_accept,
1196         .getname = vsock_getname,
1197         .poll = vsock_poll,
1198         .ioctl = sock_no_ioctl,
1199         .listen = sock_no_listen,
1200         .shutdown = vsock_shutdown,
1201         .setsockopt = sock_no_setsockopt,
1202         .getsockopt = sock_no_getsockopt,
1203         .sendmsg = vsock_dgram_sendmsg,
1204         .recvmsg = vsock_dgram_recvmsg,
1205         .mmap = sock_no_mmap,
1206         .sendpage = sock_no_sendpage,
1207 };
1208
1209 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk)
1210 {
1211         const struct vsock_transport *transport = vsk->transport;
1212
1213         if (!transport->cancel_pkt)
1214                 return -EOPNOTSUPP;
1215
1216         return transport->cancel_pkt(vsk);
1217 }
1218
1219 static void vsock_connect_timeout(struct work_struct *work)
1220 {
1221         struct sock *sk;
1222         struct vsock_sock *vsk;
1223         int cancel = 0;
1224
1225         vsk = container_of(work, struct vsock_sock, connect_work.work);
1226         sk = sk_vsock(vsk);
1227
1228         lock_sock(sk);
1229         if (sk->sk_state == TCP_SYN_SENT &&
1230             (sk->sk_shutdown != SHUTDOWN_MASK)) {
1231                 sk->sk_state = TCP_CLOSE;
1232                 sk->sk_err = ETIMEDOUT;
1233                 sk->sk_error_report(sk);
1234                 cancel = 1;
1235         }
1236         release_sock(sk);
1237         if (cancel)
1238                 vsock_transport_cancel_pkt(vsk);
1239
1240         sock_put(sk);
1241 }
1242
1243 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
1244                                 int addr_len, int flags)
1245 {
1246         int err;
1247         struct sock *sk;
1248         struct vsock_sock *vsk;
1249         const struct vsock_transport *transport;
1250         struct sockaddr_vm *remote_addr;
1251         long timeout;
1252         DEFINE_WAIT(wait);
1253
1254         err = 0;
1255         sk = sock->sk;
1256         vsk = vsock_sk(sk);
1257
1258         lock_sock(sk);
1259
1260         /* XXX AF_UNSPEC should make us disconnect like AF_INET. */
1261         switch (sock->state) {
1262         case SS_CONNECTED:
1263                 err = -EISCONN;
1264                 goto out;
1265         case SS_DISCONNECTING:
1266                 err = -EINVAL;
1267                 goto out;
1268         case SS_CONNECTING:
1269                 /* This continues on so we can move sock into the SS_CONNECTED
1270                  * state once the connection has completed (at which point err
1271                  * will be set to zero also).  Otherwise, we will either wait
1272                  * for the connection or return -EALREADY should this be a
1273                  * non-blocking call.
1274                  */
1275                 err = -EALREADY;
1276                 break;
1277         default:
1278                 if ((sk->sk_state == TCP_LISTEN) ||
1279                     vsock_addr_cast(addr, addr_len, &remote_addr) != 0) {
1280                         err = -EINVAL;
1281                         goto out;
1282                 }
1283
1284                 /* Set the remote address that we are connecting to. */
1285                 memcpy(&vsk->remote_addr, remote_addr,
1286                        sizeof(vsk->remote_addr));
1287
1288                 err = vsock_assign_transport(vsk, NULL);
1289                 if (err)
1290                         goto out;
1291
1292                 transport = vsk->transport;
1293
1294                 /* The hypervisor and well-known contexts do not have socket
1295                  * endpoints.
1296                  */
1297                 if (!transport ||
1298                     !transport->stream_allow(remote_addr->svm_cid,
1299                                              remote_addr->svm_port)) {
1300                         err = -ENETUNREACH;
1301                         goto out;
1302                 }
1303
1304                 err = vsock_auto_bind(vsk);
1305                 if (err)
1306                         goto out;
1307
1308                 sk->sk_state = TCP_SYN_SENT;
1309
1310                 err = transport->connect(vsk);
1311                 if (err < 0)
1312                         goto out;
1313
1314                 /* Mark sock as connecting and set the error code to in
1315                  * progress in case this is a non-blocking connect.
1316                  */
1317                 sock->state = SS_CONNECTING;
1318                 err = -EINPROGRESS;
1319         }
1320
1321         /* The receive path will handle all communication until we are able to
1322          * enter the connected state.  Here we wait for the connection to be
1323          * completed or a notification of an error.
1324          */
1325         timeout = vsk->connect_timeout;
1326         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1327
1328         while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) {
1329                 if (flags & O_NONBLOCK) {
1330                         /* If we're not going to block, we schedule a timeout
1331                          * function to generate a timeout on the connection
1332                          * attempt, in case the peer doesn't respond in a
1333                          * timely manner. We hold on to the socket until the
1334                          * timeout fires.
1335                          */
1336                         sock_hold(sk);
1337                         schedule_delayed_work(&vsk->connect_work, timeout);
1338
1339                         /* Skip ahead to preserve error code set above. */
1340                         goto out_wait;
1341                 }
1342
1343                 release_sock(sk);
1344                 timeout = schedule_timeout(timeout);
1345                 lock_sock(sk);
1346
1347                 if (signal_pending(current)) {
1348                         err = sock_intr_errno(timeout);
1349                         sk->sk_state = TCP_CLOSE;
1350                         sock->state = SS_UNCONNECTED;
1351                         vsock_transport_cancel_pkt(vsk);
1352                         goto out_wait;
1353                 } else if (timeout == 0) {
1354                         err = -ETIMEDOUT;
1355                         sk->sk_state = TCP_CLOSE;
1356                         sock->state = SS_UNCONNECTED;
1357                         vsock_transport_cancel_pkt(vsk);
1358                         goto out_wait;
1359                 }
1360
1361                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1362         }
1363
1364         if (sk->sk_err) {
1365                 err = -sk->sk_err;
1366                 sk->sk_state = TCP_CLOSE;
1367                 sock->state = SS_UNCONNECTED;
1368         } else {
1369                 err = 0;
1370         }
1371
1372 out_wait:
1373         finish_wait(sk_sleep(sk), &wait);
1374 out:
1375         release_sock(sk);
1376         return err;
1377 }
1378
1379 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags,
1380                         bool kern)
1381 {
1382         struct sock *listener;
1383         int err;
1384         struct sock *connected;
1385         struct vsock_sock *vconnected;
1386         long timeout;
1387         DEFINE_WAIT(wait);
1388
1389         err = 0;
1390         listener = sock->sk;
1391
1392         lock_sock(listener);
1393
1394         if (sock->type != SOCK_STREAM) {
1395                 err = -EOPNOTSUPP;
1396                 goto out;
1397         }
1398
1399         if (listener->sk_state != TCP_LISTEN) {
1400                 err = -EINVAL;
1401                 goto out;
1402         }
1403
1404         /* Wait for children sockets to appear; these are the new sockets
1405          * created upon connection establishment.
1406          */
1407         timeout = sock_sndtimeo(listener, flags & O_NONBLOCK);
1408         prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1409
1410         while ((connected = vsock_dequeue_accept(listener)) == NULL &&
1411                listener->sk_err == 0) {
1412                 release_sock(listener);
1413                 timeout = schedule_timeout(timeout);
1414                 finish_wait(sk_sleep(listener), &wait);
1415                 lock_sock(listener);
1416
1417                 if (signal_pending(current)) {
1418                         err = sock_intr_errno(timeout);
1419                         goto out;
1420                 } else if (timeout == 0) {
1421                         err = -EAGAIN;
1422                         goto out;
1423                 }
1424
1425                 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1426         }
1427         finish_wait(sk_sleep(listener), &wait);
1428
1429         if (listener->sk_err)
1430                 err = -listener->sk_err;
1431
1432         if (connected) {
1433                 sk_acceptq_removed(listener);
1434
1435                 lock_sock_nested(connected, SINGLE_DEPTH_NESTING);
1436                 vconnected = vsock_sk(connected);
1437
1438                 /* If the listener socket has received an error, then we should
1439                  * reject this socket and return.  Note that we simply mark the
1440                  * socket rejected, drop our reference, and let the cleanup
1441                  * function handle the cleanup; the fact that we found it in
1442                  * the listener's accept queue guarantees that the cleanup
1443                  * function hasn't run yet.
1444                  */
1445                 if (err) {
1446                         vconnected->rejected = true;
1447                 } else {
1448                         newsock->state = SS_CONNECTED;
1449                         sock_graft(connected, newsock);
1450                 }
1451
1452                 release_sock(connected);
1453                 sock_put(connected);
1454         }
1455
1456 out:
1457         release_sock(listener);
1458         return err;
1459 }
1460
1461 static int vsock_listen(struct socket *sock, int backlog)
1462 {
1463         int err;
1464         struct sock *sk;
1465         struct vsock_sock *vsk;
1466
1467         sk = sock->sk;
1468
1469         lock_sock(sk);
1470
1471         if (sock->type != SOCK_STREAM) {
1472                 err = -EOPNOTSUPP;
1473                 goto out;
1474         }
1475
1476         if (sock->state != SS_UNCONNECTED) {
1477                 err = -EINVAL;
1478                 goto out;
1479         }
1480
1481         vsk = vsock_sk(sk);
1482
1483         if (!vsock_addr_bound(&vsk->local_addr)) {
1484                 err = -EINVAL;
1485                 goto out;
1486         }
1487
1488         sk->sk_max_ack_backlog = backlog;
1489         sk->sk_state = TCP_LISTEN;
1490
1491         err = 0;
1492
1493 out:
1494         release_sock(sk);
1495         return err;
1496 }
1497
1498 static void vsock_update_buffer_size(struct vsock_sock *vsk,
1499                                      const struct vsock_transport *transport,
1500                                      u64 val)
1501 {
1502         if (val > vsk->buffer_max_size)
1503                 val = vsk->buffer_max_size;
1504
1505         if (val < vsk->buffer_min_size)
1506                 val = vsk->buffer_min_size;
1507
1508         if (val != vsk->buffer_size &&
1509             transport && transport->notify_buffer_size)
1510                 transport->notify_buffer_size(vsk, &val);
1511
1512         vsk->buffer_size = val;
1513 }
1514
1515 static int vsock_stream_setsockopt(struct socket *sock,
1516                                    int level,
1517                                    int optname,
1518                                    char __user *optval,
1519                                    unsigned int optlen)
1520 {
1521         int err;
1522         struct sock *sk;
1523         struct vsock_sock *vsk;
1524         const struct vsock_transport *transport;
1525         u64 val;
1526
1527         if (level != AF_VSOCK)
1528                 return -ENOPROTOOPT;
1529
1530 #define COPY_IN(_v)                                       \
1531         do {                                              \
1532                 if (optlen < sizeof(_v)) {                \
1533                         err = -EINVAL;                    \
1534                         goto exit;                        \
1535                 }                                         \
1536                 if (copy_from_user(&_v, optval, sizeof(_v)) != 0) {     \
1537                         err = -EFAULT;                                  \
1538                         goto exit;                                      \
1539                 }                                                       \
1540         } while (0)
1541
1542         err = 0;
1543         sk = sock->sk;
1544         vsk = vsock_sk(sk);
1545         transport = vsk->transport;
1546
1547         lock_sock(sk);
1548
1549         switch (optname) {
1550         case SO_VM_SOCKETS_BUFFER_SIZE:
1551                 COPY_IN(val);
1552                 vsock_update_buffer_size(vsk, transport, val);
1553                 break;
1554
1555         case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1556                 COPY_IN(val);
1557                 vsk->buffer_max_size = val;
1558                 vsock_update_buffer_size(vsk, transport, vsk->buffer_size);
1559                 break;
1560
1561         case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1562                 COPY_IN(val);
1563                 vsk->buffer_min_size = val;
1564                 vsock_update_buffer_size(vsk, transport, vsk->buffer_size);
1565                 break;
1566
1567         case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1568                 struct __kernel_old_timeval tv;
1569                 COPY_IN(tv);
1570                 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC &&
1571                     tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) {
1572                         vsk->connect_timeout = tv.tv_sec * HZ +
1573                             DIV_ROUND_UP(tv.tv_usec, (1000000 / HZ));
1574                         if (vsk->connect_timeout == 0)
1575                                 vsk->connect_timeout =
1576                                     VSOCK_DEFAULT_CONNECT_TIMEOUT;
1577
1578                 } else {
1579                         err = -ERANGE;
1580                 }
1581                 break;
1582         }
1583
1584         default:
1585                 err = -ENOPROTOOPT;
1586                 break;
1587         }
1588
1589 #undef COPY_IN
1590
1591 exit:
1592         release_sock(sk);
1593         return err;
1594 }
1595
1596 static int vsock_stream_getsockopt(struct socket *sock,
1597                                    int level, int optname,
1598                                    char __user *optval,
1599                                    int __user *optlen)
1600 {
1601         int err;
1602         int len;
1603         struct sock *sk;
1604         struct vsock_sock *vsk;
1605         u64 val;
1606
1607         if (level != AF_VSOCK)
1608                 return -ENOPROTOOPT;
1609
1610         err = get_user(len, optlen);
1611         if (err != 0)
1612                 return err;
1613
1614 #define COPY_OUT(_v)                            \
1615         do {                                    \
1616                 if (len < sizeof(_v))           \
1617                         return -EINVAL;         \
1618                                                 \
1619                 len = sizeof(_v);               \
1620                 if (copy_to_user(optval, &_v, len) != 0)        \
1621                         return -EFAULT;                         \
1622                                                                 \
1623         } while (0)
1624
1625         err = 0;
1626         sk = sock->sk;
1627         vsk = vsock_sk(sk);
1628
1629         switch (optname) {
1630         case SO_VM_SOCKETS_BUFFER_SIZE:
1631                 val = vsk->buffer_size;
1632                 COPY_OUT(val);
1633                 break;
1634
1635         case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1636                 val = vsk->buffer_max_size;
1637                 COPY_OUT(val);
1638                 break;
1639
1640         case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1641                 val = vsk->buffer_min_size;
1642                 COPY_OUT(val);
1643                 break;
1644
1645         case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1646                 struct __kernel_old_timeval tv;
1647                 tv.tv_sec = vsk->connect_timeout / HZ;
1648                 tv.tv_usec =
1649                     (vsk->connect_timeout -
1650                      tv.tv_sec * HZ) * (1000000 / HZ);
1651                 COPY_OUT(tv);
1652                 break;
1653         }
1654         default:
1655                 return -ENOPROTOOPT;
1656         }
1657
1658         err = put_user(len, optlen);
1659         if (err != 0)
1660                 return -EFAULT;
1661
1662 #undef COPY_OUT
1663
1664         return 0;
1665 }
1666
1667 static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
1668                                 size_t len)
1669 {
1670         struct sock *sk;
1671         struct vsock_sock *vsk;
1672         const struct vsock_transport *transport;
1673         ssize_t total_written;
1674         long timeout;
1675         int err;
1676         struct vsock_transport_send_notify_data send_data;
1677         DEFINE_WAIT_FUNC(wait, woken_wake_function);
1678
1679         sk = sock->sk;
1680         vsk = vsock_sk(sk);
1681         transport = vsk->transport;
1682         total_written = 0;
1683         err = 0;
1684
1685         if (msg->msg_flags & MSG_OOB)
1686                 return -EOPNOTSUPP;
1687
1688         lock_sock(sk);
1689
1690         /* Callers should not provide a destination with stream sockets. */
1691         if (msg->msg_namelen) {
1692                 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP;
1693                 goto out;
1694         }
1695
1696         /* Send data only if both sides are not shutdown in the direction. */
1697         if (sk->sk_shutdown & SEND_SHUTDOWN ||
1698             vsk->peer_shutdown & RCV_SHUTDOWN) {
1699                 err = -EPIPE;
1700                 goto out;
1701         }
1702
1703         if (!transport || sk->sk_state != TCP_ESTABLISHED ||
1704             !vsock_addr_bound(&vsk->local_addr)) {
1705                 err = -ENOTCONN;
1706                 goto out;
1707         }
1708
1709         if (!vsock_addr_bound(&vsk->remote_addr)) {
1710                 err = -EDESTADDRREQ;
1711                 goto out;
1712         }
1713
1714         /* Wait for room in the produce queue to enqueue our user's data. */
1715         timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1716
1717         err = transport->notify_send_init(vsk, &send_data);
1718         if (err < 0)
1719                 goto out;
1720
1721         while (total_written < len) {
1722                 ssize_t written;
1723
1724                 add_wait_queue(sk_sleep(sk), &wait);
1725                 while (vsock_stream_has_space(vsk) == 0 &&
1726                        sk->sk_err == 0 &&
1727                        !(sk->sk_shutdown & SEND_SHUTDOWN) &&
1728                        !(vsk->peer_shutdown & RCV_SHUTDOWN)) {
1729
1730                         /* Don't wait for non-blocking sockets. */
1731                         if (timeout == 0) {
1732                                 err = -EAGAIN;
1733                                 remove_wait_queue(sk_sleep(sk), &wait);
1734                                 goto out_err;
1735                         }
1736
1737                         err = transport->notify_send_pre_block(vsk, &send_data);
1738                         if (err < 0) {
1739                                 remove_wait_queue(sk_sleep(sk), &wait);
1740                                 goto out_err;
1741                         }
1742
1743                         release_sock(sk);
1744                         timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout);
1745                         lock_sock(sk);
1746                         if (signal_pending(current)) {
1747                                 err = sock_intr_errno(timeout);
1748                                 remove_wait_queue(sk_sleep(sk), &wait);
1749                                 goto out_err;
1750                         } else if (timeout == 0) {
1751                                 err = -EAGAIN;
1752                                 remove_wait_queue(sk_sleep(sk), &wait);
1753                                 goto out_err;
1754                         }
1755                 }
1756                 remove_wait_queue(sk_sleep(sk), &wait);
1757
1758                 /* These checks occur both as part of and after the loop
1759                  * conditional since we need to check before and after
1760                  * sleeping.
1761                  */
1762                 if (sk->sk_err) {
1763                         err = -sk->sk_err;
1764                         goto out_err;
1765                 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) ||
1766                            (vsk->peer_shutdown & RCV_SHUTDOWN)) {
1767                         err = -EPIPE;
1768                         goto out_err;
1769                 }
1770
1771                 err = transport->notify_send_pre_enqueue(vsk, &send_data);
1772                 if (err < 0)
1773                         goto out_err;
1774
1775                 /* Note that enqueue will only write as many bytes as are free
1776                  * in the produce queue, so we don't need to ensure len is
1777                  * smaller than the queue size.  It is the caller's
1778                  * responsibility to check how many bytes we were able to send.
1779                  */
1780
1781                 written = transport->stream_enqueue(
1782                                 vsk, msg,
1783                                 len - total_written);
1784                 if (written < 0) {
1785                         err = -ENOMEM;
1786                         goto out_err;
1787                 }
1788
1789                 total_written += written;
1790
1791                 err = transport->notify_send_post_enqueue(
1792                                 vsk, written, &send_data);
1793                 if (err < 0)
1794                         goto out_err;
1795
1796         }
1797
1798 out_err:
1799         if (total_written > 0)
1800                 err = total_written;
1801 out:
1802         release_sock(sk);
1803         return err;
1804 }
1805
1806
1807 static int
1808 vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1809                      int flags)
1810 {
1811         struct sock *sk;
1812         struct vsock_sock *vsk;
1813         const struct vsock_transport *transport;
1814         int err;
1815         size_t target;
1816         ssize_t copied;
1817         long timeout;
1818         struct vsock_transport_recv_notify_data recv_data;
1819
1820         DEFINE_WAIT(wait);
1821
1822         sk = sock->sk;
1823         vsk = vsock_sk(sk);
1824         transport = vsk->transport;
1825         err = 0;
1826
1827         lock_sock(sk);
1828
1829         if (!transport || sk->sk_state != TCP_ESTABLISHED) {
1830                 /* Recvmsg is supposed to return 0 if a peer performs an
1831                  * orderly shutdown. Differentiate between that case and when a
1832                  * peer has not connected or a local shutdown occured with the
1833                  * SOCK_DONE flag.
1834                  */
1835                 if (sock_flag(sk, SOCK_DONE))
1836                         err = 0;
1837                 else
1838                         err = -ENOTCONN;
1839
1840                 goto out;
1841         }
1842
1843         if (flags & MSG_OOB) {
1844                 err = -EOPNOTSUPP;
1845                 goto out;
1846         }
1847
1848         /* We don't check peer_shutdown flag here since peer may actually shut
1849          * down, but there can be data in the queue that a local socket can
1850          * receive.
1851          */
1852         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1853                 err = 0;
1854                 goto out;
1855         }
1856
1857         /* It is valid on Linux to pass in a zero-length receive buffer.  This
1858          * is not an error.  We may as well bail out now.
1859          */
1860         if (!len) {
1861                 err = 0;
1862                 goto out;
1863         }
1864
1865         /* We must not copy less than target bytes into the user's buffer
1866          * before returning successfully, so we wait for the consume queue to
1867          * have that much data to consume before dequeueing.  Note that this
1868          * makes it impossible to handle cases where target is greater than the
1869          * queue size.
1870          */
1871         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1872         if (target >= transport->stream_rcvhiwat(vsk)) {
1873                 err = -ENOMEM;
1874                 goto out;
1875         }
1876         timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1877         copied = 0;
1878
1879         err = transport->notify_recv_init(vsk, target, &recv_data);
1880         if (err < 0)
1881                 goto out;
1882
1883
1884         while (1) {
1885                 s64 ready;
1886
1887                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1888                 ready = vsock_stream_has_data(vsk);
1889
1890                 if (ready == 0) {
1891                         if (sk->sk_err != 0 ||
1892                             (sk->sk_shutdown & RCV_SHUTDOWN) ||
1893                             (vsk->peer_shutdown & SEND_SHUTDOWN)) {
1894                                 finish_wait(sk_sleep(sk), &wait);
1895                                 break;
1896                         }
1897                         /* Don't wait for non-blocking sockets. */
1898                         if (timeout == 0) {
1899                                 err = -EAGAIN;
1900                                 finish_wait(sk_sleep(sk), &wait);
1901                                 break;
1902                         }
1903
1904                         err = transport->notify_recv_pre_block(
1905                                         vsk, target, &recv_data);
1906                         if (err < 0) {
1907                                 finish_wait(sk_sleep(sk), &wait);
1908                                 break;
1909                         }
1910                         release_sock(sk);
1911                         timeout = schedule_timeout(timeout);
1912                         lock_sock(sk);
1913
1914                         if (signal_pending(current)) {
1915                                 err = sock_intr_errno(timeout);
1916                                 finish_wait(sk_sleep(sk), &wait);
1917                                 break;
1918                         } else if (timeout == 0) {
1919                                 err = -EAGAIN;
1920                                 finish_wait(sk_sleep(sk), &wait);
1921                                 break;
1922                         }
1923                 } else {
1924                         ssize_t read;
1925
1926                         finish_wait(sk_sleep(sk), &wait);
1927
1928                         if (ready < 0) {
1929                                 /* Invalid queue pair content. XXX This should
1930                                 * be changed to a connection reset in a later
1931                                 * change.
1932                                 */
1933
1934                                 err = -ENOMEM;
1935                                 goto out;
1936                         }
1937
1938                         err = transport->notify_recv_pre_dequeue(
1939                                         vsk, target, &recv_data);
1940                         if (err < 0)
1941                                 break;
1942
1943                         read = transport->stream_dequeue(
1944                                         vsk, msg,
1945                                         len - copied, flags);
1946                         if (read < 0) {
1947                                 err = -ENOMEM;
1948                                 break;
1949                         }
1950
1951                         copied += read;
1952
1953                         err = transport->notify_recv_post_dequeue(
1954                                         vsk, target, read,
1955                                         !(flags & MSG_PEEK), &recv_data);
1956                         if (err < 0)
1957                                 goto out;
1958
1959                         if (read >= target || flags & MSG_PEEK)
1960                                 break;
1961
1962                         target -= read;
1963                 }
1964         }
1965
1966         if (sk->sk_err)
1967                 err = -sk->sk_err;
1968         else if (sk->sk_shutdown & RCV_SHUTDOWN)
1969                 err = 0;
1970
1971         if (copied > 0)
1972                 err = copied;
1973
1974 out:
1975         release_sock(sk);
1976         return err;
1977 }
1978
1979 static const struct proto_ops vsock_stream_ops = {
1980         .family = PF_VSOCK,
1981         .owner = THIS_MODULE,
1982         .release = vsock_release,
1983         .bind = vsock_bind,
1984         .connect = vsock_stream_connect,
1985         .socketpair = sock_no_socketpair,
1986         .accept = vsock_accept,
1987         .getname = vsock_getname,
1988         .poll = vsock_poll,
1989         .ioctl = sock_no_ioctl,
1990         .listen = vsock_listen,
1991         .shutdown = vsock_shutdown,
1992         .setsockopt = vsock_stream_setsockopt,
1993         .getsockopt = vsock_stream_getsockopt,
1994         .sendmsg = vsock_stream_sendmsg,
1995         .recvmsg = vsock_stream_recvmsg,
1996         .mmap = sock_no_mmap,
1997         .sendpage = sock_no_sendpage,
1998 };
1999
2000 static int vsock_create(struct net *net, struct socket *sock,
2001                         int protocol, int kern)
2002 {
2003         struct vsock_sock *vsk;
2004         struct sock *sk;
2005         int ret;
2006
2007         if (!sock)
2008                 return -EINVAL;
2009
2010         if (protocol && protocol != PF_VSOCK)
2011                 return -EPROTONOSUPPORT;
2012
2013         switch (sock->type) {
2014         case SOCK_DGRAM:
2015                 sock->ops = &vsock_dgram_ops;
2016                 break;
2017         case SOCK_STREAM:
2018                 sock->ops = &vsock_stream_ops;
2019                 break;
2020         default:
2021                 return -ESOCKTNOSUPPORT;
2022         }
2023
2024         sock->state = SS_UNCONNECTED;
2025
2026         sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern);
2027         if (!sk)
2028                 return -ENOMEM;
2029
2030         vsk = vsock_sk(sk);
2031
2032         if (sock->type == SOCK_DGRAM) {
2033                 ret = vsock_assign_transport(vsk, NULL);
2034                 if (ret < 0) {
2035                         sock_put(sk);
2036                         return ret;
2037                 }
2038         }
2039
2040         vsock_insert_unbound(vsk);
2041
2042         return 0;
2043 }
2044
2045 static const struct net_proto_family vsock_family_ops = {
2046         .family = AF_VSOCK,
2047         .create = vsock_create,
2048         .owner = THIS_MODULE,
2049 };
2050
2051 static long vsock_dev_do_ioctl(struct file *filp,
2052                                unsigned int cmd, void __user *ptr)
2053 {
2054         u32 __user *p = ptr;
2055         u32 cid = VMADDR_CID_ANY;
2056         int retval = 0;
2057
2058         switch (cmd) {
2059         case IOCTL_VM_SOCKETS_GET_LOCAL_CID:
2060                 /* To be compatible with the VMCI behavior, we prioritize the
2061                  * guest CID instead of well-know host CID (VMADDR_CID_HOST).
2062                  */
2063                 if (transport_g2h)
2064                         cid = transport_g2h->get_local_cid();
2065                 else if (transport_h2g)
2066                         cid = transport_h2g->get_local_cid();
2067
2068                 if (put_user(cid, p) != 0)
2069                         retval = -EFAULT;
2070                 break;
2071
2072         default:
2073                 pr_err("Unknown ioctl %d\n", cmd);
2074                 retval = -EINVAL;
2075         }
2076
2077         return retval;
2078 }
2079
2080 static long vsock_dev_ioctl(struct file *filp,
2081                             unsigned int cmd, unsigned long arg)
2082 {
2083         return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg);
2084 }
2085
2086 #ifdef CONFIG_COMPAT
2087 static long vsock_dev_compat_ioctl(struct file *filp,
2088                                    unsigned int cmd, unsigned long arg)
2089 {
2090         return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg));
2091 }
2092 #endif
2093
2094 static const struct file_operations vsock_device_ops = {
2095         .owner          = THIS_MODULE,
2096         .unlocked_ioctl = vsock_dev_ioctl,
2097 #ifdef CONFIG_COMPAT
2098         .compat_ioctl   = vsock_dev_compat_ioctl,
2099 #endif
2100         .open           = nonseekable_open,
2101 };
2102
2103 static struct miscdevice vsock_device = {
2104         .name           = "vsock",
2105         .fops           = &vsock_device_ops,
2106 };
2107
2108 static int __init vsock_init(void)
2109 {
2110         int err = 0;
2111
2112         vsock_init_tables();
2113
2114         vsock_proto.owner = THIS_MODULE;
2115         vsock_device.minor = MISC_DYNAMIC_MINOR;
2116         err = misc_register(&vsock_device);
2117         if (err) {
2118                 pr_err("Failed to register misc device\n");
2119                 goto err_reset_transport;
2120         }
2121
2122         err = proto_register(&vsock_proto, 1);  /* we want our slab */
2123         if (err) {
2124                 pr_err("Cannot register vsock protocol\n");
2125                 goto err_deregister_misc;
2126         }
2127
2128         err = sock_register(&vsock_family_ops);
2129         if (err) {
2130                 pr_err("could not register af_vsock (%d) address family: %d\n",
2131                        AF_VSOCK, err);
2132                 goto err_unregister_proto;
2133         }
2134
2135         return 0;
2136
2137 err_unregister_proto:
2138         proto_unregister(&vsock_proto);
2139 err_deregister_misc:
2140         misc_deregister(&vsock_device);
2141 err_reset_transport:
2142         return err;
2143 }
2144
2145 static void __exit vsock_exit(void)
2146 {
2147         misc_deregister(&vsock_device);
2148         sock_unregister(AF_VSOCK);
2149         proto_unregister(&vsock_proto);
2150 }
2151
2152 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk)
2153 {
2154         return vsk->transport;
2155 }
2156 EXPORT_SYMBOL_GPL(vsock_core_get_transport);
2157
2158 int vsock_core_register(const struct vsock_transport *t, int features)
2159 {
2160         const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local;
2161         int err = mutex_lock_interruptible(&vsock_register_mutex);
2162
2163         if (err)
2164                 return err;
2165
2166         t_h2g = transport_h2g;
2167         t_g2h = transport_g2h;
2168         t_dgram = transport_dgram;
2169         t_local = transport_local;
2170
2171         if (features & VSOCK_TRANSPORT_F_H2G) {
2172                 if (t_h2g) {
2173                         err = -EBUSY;
2174                         goto err_busy;
2175                 }
2176                 t_h2g = t;
2177         }
2178
2179         if (features & VSOCK_TRANSPORT_F_G2H) {
2180                 if (t_g2h) {
2181                         err = -EBUSY;
2182                         goto err_busy;
2183                 }
2184                 t_g2h = t;
2185         }
2186
2187         if (features & VSOCK_TRANSPORT_F_DGRAM) {
2188                 if (t_dgram) {
2189                         err = -EBUSY;
2190                         goto err_busy;
2191                 }
2192                 t_dgram = t;
2193         }
2194
2195         if (features & VSOCK_TRANSPORT_F_LOCAL) {
2196                 if (t_local) {
2197                         err = -EBUSY;
2198                         goto err_busy;
2199                 }
2200                 t_local = t;
2201         }
2202
2203         transport_h2g = t_h2g;
2204         transport_g2h = t_g2h;
2205         transport_dgram = t_dgram;
2206         transport_local = t_local;
2207
2208 err_busy:
2209         mutex_unlock(&vsock_register_mutex);
2210         return err;
2211 }
2212 EXPORT_SYMBOL_GPL(vsock_core_register);
2213
2214 void vsock_core_unregister(const struct vsock_transport *t)
2215 {
2216         mutex_lock(&vsock_register_mutex);
2217
2218         if (transport_h2g == t)
2219                 transport_h2g = NULL;
2220
2221         if (transport_g2h == t)
2222                 transport_g2h = NULL;
2223
2224         if (transport_dgram == t)
2225                 transport_dgram = NULL;
2226
2227         if (transport_local == t)
2228                 transport_local = NULL;
2229
2230         mutex_unlock(&vsock_register_mutex);
2231 }
2232 EXPORT_SYMBOL_GPL(vsock_core_unregister);
2233
2234 module_init(vsock_init);
2235 module_exit(vsock_exit);
2236
2237 MODULE_AUTHOR("VMware, Inc.");
2238 MODULE_DESCRIPTION("VMware Virtual Socket Family");
2239 MODULE_VERSION("1.0.2.0-k");
2240 MODULE_LICENSE("GPL v2");