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 (transport && 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         .sendmsg = vsock_dgram_sendmsg,
1206         .recvmsg = vsock_dgram_recvmsg,
1207         .mmap = sock_no_mmap,
1208         .sendpage = sock_no_sendpage,
1209 };
1210
1211 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk)
1212 {
1213         const struct vsock_transport *transport = vsk->transport;
1214
1215         if (!transport->cancel_pkt)
1216                 return -EOPNOTSUPP;
1217
1218         return transport->cancel_pkt(vsk);
1219 }
1220
1221 static void vsock_connect_timeout(struct work_struct *work)
1222 {
1223         struct sock *sk;
1224         struct vsock_sock *vsk;
1225         int cancel = 0;
1226
1227         vsk = container_of(work, struct vsock_sock, connect_work.work);
1228         sk = sk_vsock(vsk);
1229
1230         lock_sock(sk);
1231         if (sk->sk_state == TCP_SYN_SENT &&
1232             (sk->sk_shutdown != SHUTDOWN_MASK)) {
1233                 sk->sk_state = TCP_CLOSE;
1234                 sk->sk_err = ETIMEDOUT;
1235                 sk->sk_error_report(sk);
1236                 cancel = 1;
1237         }
1238         release_sock(sk);
1239         if (cancel)
1240                 vsock_transport_cancel_pkt(vsk);
1241
1242         sock_put(sk);
1243 }
1244
1245 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
1246                                 int addr_len, int flags)
1247 {
1248         int err;
1249         struct sock *sk;
1250         struct vsock_sock *vsk;
1251         const struct vsock_transport *transport;
1252         struct sockaddr_vm *remote_addr;
1253         long timeout;
1254         DEFINE_WAIT(wait);
1255
1256         err = 0;
1257         sk = sock->sk;
1258         vsk = vsock_sk(sk);
1259
1260         lock_sock(sk);
1261
1262         /* XXX AF_UNSPEC should make us disconnect like AF_INET. */
1263         switch (sock->state) {
1264         case SS_CONNECTED:
1265                 err = -EISCONN;
1266                 goto out;
1267         case SS_DISCONNECTING:
1268                 err = -EINVAL;
1269                 goto out;
1270         case SS_CONNECTING:
1271                 /* This continues on so we can move sock into the SS_CONNECTED
1272                  * state once the connection has completed (at which point err
1273                  * will be set to zero also).  Otherwise, we will either wait
1274                  * for the connection or return -EALREADY should this be a
1275                  * non-blocking call.
1276                  */
1277                 err = -EALREADY;
1278                 break;
1279         default:
1280                 if ((sk->sk_state == TCP_LISTEN) ||
1281                     vsock_addr_cast(addr, addr_len, &remote_addr) != 0) {
1282                         err = -EINVAL;
1283                         goto out;
1284                 }
1285
1286                 /* Set the remote address that we are connecting to. */
1287                 memcpy(&vsk->remote_addr, remote_addr,
1288                        sizeof(vsk->remote_addr));
1289
1290                 err = vsock_assign_transport(vsk, NULL);
1291                 if (err)
1292                         goto out;
1293
1294                 transport = vsk->transport;
1295
1296                 /* The hypervisor and well-known contexts do not have socket
1297                  * endpoints.
1298                  */
1299                 if (!transport ||
1300                     !transport->stream_allow(remote_addr->svm_cid,
1301                                              remote_addr->svm_port)) {
1302                         err = -ENETUNREACH;
1303                         goto out;
1304                 }
1305
1306                 err = vsock_auto_bind(vsk);
1307                 if (err)
1308                         goto out;
1309
1310                 sk->sk_state = TCP_SYN_SENT;
1311
1312                 err = transport->connect(vsk);
1313                 if (err < 0)
1314                         goto out;
1315
1316                 /* Mark sock as connecting and set the error code to in
1317                  * progress in case this is a non-blocking connect.
1318                  */
1319                 sock->state = SS_CONNECTING;
1320                 err = -EINPROGRESS;
1321         }
1322
1323         /* The receive path will handle all communication until we are able to
1324          * enter the connected state.  Here we wait for the connection to be
1325          * completed or a notification of an error.
1326          */
1327         timeout = vsk->connect_timeout;
1328         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1329
1330         while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) {
1331                 if (flags & O_NONBLOCK) {
1332                         /* If we're not going to block, we schedule a timeout
1333                          * function to generate a timeout on the connection
1334                          * attempt, in case the peer doesn't respond in a
1335                          * timely manner. We hold on to the socket until the
1336                          * timeout fires.
1337                          */
1338                         sock_hold(sk);
1339                         schedule_delayed_work(&vsk->connect_work, timeout);
1340
1341                         /* Skip ahead to preserve error code set above. */
1342                         goto out_wait;
1343                 }
1344
1345                 release_sock(sk);
1346                 timeout = schedule_timeout(timeout);
1347                 lock_sock(sk);
1348
1349                 if (signal_pending(current)) {
1350                         err = sock_intr_errno(timeout);
1351                         sk->sk_state = TCP_CLOSE;
1352                         sock->state = SS_UNCONNECTED;
1353                         vsock_transport_cancel_pkt(vsk);
1354                         goto out_wait;
1355                 } else if (timeout == 0) {
1356                         err = -ETIMEDOUT;
1357                         sk->sk_state = TCP_CLOSE;
1358                         sock->state = SS_UNCONNECTED;
1359                         vsock_transport_cancel_pkt(vsk);
1360                         goto out_wait;
1361                 }
1362
1363                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1364         }
1365
1366         if (sk->sk_err) {
1367                 err = -sk->sk_err;
1368                 sk->sk_state = TCP_CLOSE;
1369                 sock->state = SS_UNCONNECTED;
1370         } else {
1371                 err = 0;
1372         }
1373
1374 out_wait:
1375         finish_wait(sk_sleep(sk), &wait);
1376 out:
1377         release_sock(sk);
1378         return err;
1379 }
1380
1381 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags,
1382                         bool kern)
1383 {
1384         struct sock *listener;
1385         int err;
1386         struct sock *connected;
1387         struct vsock_sock *vconnected;
1388         long timeout;
1389         DEFINE_WAIT(wait);
1390
1391         err = 0;
1392         listener = sock->sk;
1393
1394         lock_sock(listener);
1395
1396         if (sock->type != SOCK_STREAM) {
1397                 err = -EOPNOTSUPP;
1398                 goto out;
1399         }
1400
1401         if (listener->sk_state != TCP_LISTEN) {
1402                 err = -EINVAL;
1403                 goto out;
1404         }
1405
1406         /* Wait for children sockets to appear; these are the new sockets
1407          * created upon connection establishment.
1408          */
1409         timeout = sock_rcvtimeo(listener, flags & O_NONBLOCK);
1410         prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1411
1412         while ((connected = vsock_dequeue_accept(listener)) == NULL &&
1413                listener->sk_err == 0) {
1414                 release_sock(listener);
1415                 timeout = schedule_timeout(timeout);
1416                 finish_wait(sk_sleep(listener), &wait);
1417                 lock_sock(listener);
1418
1419                 if (signal_pending(current)) {
1420                         err = sock_intr_errno(timeout);
1421                         goto out;
1422                 } else if (timeout == 0) {
1423                         err = -EAGAIN;
1424                         goto out;
1425                 }
1426
1427                 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1428         }
1429         finish_wait(sk_sleep(listener), &wait);
1430
1431         if (listener->sk_err)
1432                 err = -listener->sk_err;
1433
1434         if (connected) {
1435                 sk_acceptq_removed(listener);
1436
1437                 lock_sock_nested(connected, SINGLE_DEPTH_NESTING);
1438                 vconnected = vsock_sk(connected);
1439
1440                 /* If the listener socket has received an error, then we should
1441                  * reject this socket and return.  Note that we simply mark the
1442                  * socket rejected, drop our reference, and let the cleanup
1443                  * function handle the cleanup; the fact that we found it in
1444                  * the listener's accept queue guarantees that the cleanup
1445                  * function hasn't run yet.
1446                  */
1447                 if (err) {
1448                         vconnected->rejected = true;
1449                 } else {
1450                         newsock->state = SS_CONNECTED;
1451                         sock_graft(connected, newsock);
1452                 }
1453
1454                 release_sock(connected);
1455                 sock_put(connected);
1456         }
1457
1458 out:
1459         release_sock(listener);
1460         return err;
1461 }
1462
1463 static int vsock_listen(struct socket *sock, int backlog)
1464 {
1465         int err;
1466         struct sock *sk;
1467         struct vsock_sock *vsk;
1468
1469         sk = sock->sk;
1470
1471         lock_sock(sk);
1472
1473         if (sock->type != SOCK_STREAM) {
1474                 err = -EOPNOTSUPP;
1475                 goto out;
1476         }
1477
1478         if (sock->state != SS_UNCONNECTED) {
1479                 err = -EINVAL;
1480                 goto out;
1481         }
1482
1483         vsk = vsock_sk(sk);
1484
1485         if (!vsock_addr_bound(&vsk->local_addr)) {
1486                 err = -EINVAL;
1487                 goto out;
1488         }
1489
1490         sk->sk_max_ack_backlog = backlog;
1491         sk->sk_state = TCP_LISTEN;
1492
1493         err = 0;
1494
1495 out:
1496         release_sock(sk);
1497         return err;
1498 }
1499
1500 static void vsock_update_buffer_size(struct vsock_sock *vsk,
1501                                      const struct vsock_transport *transport,
1502                                      u64 val)
1503 {
1504         if (val > vsk->buffer_max_size)
1505                 val = vsk->buffer_max_size;
1506
1507         if (val < vsk->buffer_min_size)
1508                 val = vsk->buffer_min_size;
1509
1510         if (val != vsk->buffer_size &&
1511             transport && transport->notify_buffer_size)
1512                 transport->notify_buffer_size(vsk, &val);
1513
1514         vsk->buffer_size = val;
1515 }
1516
1517 static int vsock_stream_setsockopt(struct socket *sock,
1518                                    int level,
1519                                    int optname,
1520                                    sockptr_t optval,
1521                                    unsigned int optlen)
1522 {
1523         int err;
1524         struct sock *sk;
1525         struct vsock_sock *vsk;
1526         const struct vsock_transport *transport;
1527         u64 val;
1528
1529         if (level != AF_VSOCK)
1530                 return -ENOPROTOOPT;
1531
1532 #define COPY_IN(_v)                                       \
1533         do {                                              \
1534                 if (optlen < sizeof(_v)) {                \
1535                         err = -EINVAL;                    \
1536                         goto exit;                        \
1537                 }                                         \
1538                 if (copy_from_sockptr(&_v, optval, sizeof(_v)) != 0) {  \
1539                         err = -EFAULT;                                  \
1540                         goto exit;                                      \
1541                 }                                                       \
1542         } while (0)
1543
1544         err = 0;
1545         sk = sock->sk;
1546         vsk = vsock_sk(sk);
1547         transport = vsk->transport;
1548
1549         lock_sock(sk);
1550
1551         switch (optname) {
1552         case SO_VM_SOCKETS_BUFFER_SIZE:
1553                 COPY_IN(val);
1554                 vsock_update_buffer_size(vsk, transport, val);
1555                 break;
1556
1557         case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1558                 COPY_IN(val);
1559                 vsk->buffer_max_size = val;
1560                 vsock_update_buffer_size(vsk, transport, vsk->buffer_size);
1561                 break;
1562
1563         case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1564                 COPY_IN(val);
1565                 vsk->buffer_min_size = val;
1566                 vsock_update_buffer_size(vsk, transport, vsk->buffer_size);
1567                 break;
1568
1569         case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1570                 struct __kernel_old_timeval tv;
1571                 COPY_IN(tv);
1572                 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC &&
1573                     tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) {
1574                         vsk->connect_timeout = tv.tv_sec * HZ +
1575                             DIV_ROUND_UP(tv.tv_usec, (1000000 / HZ));
1576                         if (vsk->connect_timeout == 0)
1577                                 vsk->connect_timeout =
1578                                     VSOCK_DEFAULT_CONNECT_TIMEOUT;
1579
1580                 } else {
1581                         err = -ERANGE;
1582                 }
1583                 break;
1584         }
1585
1586         default:
1587                 err = -ENOPROTOOPT;
1588                 break;
1589         }
1590
1591 #undef COPY_IN
1592
1593 exit:
1594         release_sock(sk);
1595         return err;
1596 }
1597
1598 static int vsock_stream_getsockopt(struct socket *sock,
1599                                    int level, int optname,
1600                                    char __user *optval,
1601                                    int __user *optlen)
1602 {
1603         int err;
1604         int len;
1605         struct sock *sk;
1606         struct vsock_sock *vsk;
1607         u64 val;
1608
1609         if (level != AF_VSOCK)
1610                 return -ENOPROTOOPT;
1611
1612         err = get_user(len, optlen);
1613         if (err != 0)
1614                 return err;
1615
1616 #define COPY_OUT(_v)                            \
1617         do {                                    \
1618                 if (len < sizeof(_v))           \
1619                         return -EINVAL;         \
1620                                                 \
1621                 len = sizeof(_v);               \
1622                 if (copy_to_user(optval, &_v, len) != 0)        \
1623                         return -EFAULT;                         \
1624                                                                 \
1625         } while (0)
1626
1627         err = 0;
1628         sk = sock->sk;
1629         vsk = vsock_sk(sk);
1630
1631         switch (optname) {
1632         case SO_VM_SOCKETS_BUFFER_SIZE:
1633                 val = vsk->buffer_size;
1634                 COPY_OUT(val);
1635                 break;
1636
1637         case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1638                 val = vsk->buffer_max_size;
1639                 COPY_OUT(val);
1640                 break;
1641
1642         case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1643                 val = vsk->buffer_min_size;
1644                 COPY_OUT(val);
1645                 break;
1646
1647         case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1648                 struct __kernel_old_timeval tv;
1649                 tv.tv_sec = vsk->connect_timeout / HZ;
1650                 tv.tv_usec =
1651                     (vsk->connect_timeout -
1652                      tv.tv_sec * HZ) * (1000000 / HZ);
1653                 COPY_OUT(tv);
1654                 break;
1655         }
1656         default:
1657                 return -ENOPROTOOPT;
1658         }
1659
1660         err = put_user(len, optlen);
1661         if (err != 0)
1662                 return -EFAULT;
1663
1664 #undef COPY_OUT
1665
1666         return 0;
1667 }
1668
1669 static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
1670                                 size_t len)
1671 {
1672         struct sock *sk;
1673         struct vsock_sock *vsk;
1674         const struct vsock_transport *transport;
1675         ssize_t total_written;
1676         long timeout;
1677         int err;
1678         struct vsock_transport_send_notify_data send_data;
1679         DEFINE_WAIT_FUNC(wait, woken_wake_function);
1680
1681         sk = sock->sk;
1682         vsk = vsock_sk(sk);
1683         transport = vsk->transport;
1684         total_written = 0;
1685         err = 0;
1686
1687         if (msg->msg_flags & MSG_OOB)
1688                 return -EOPNOTSUPP;
1689
1690         lock_sock(sk);
1691
1692         /* Callers should not provide a destination with stream sockets. */
1693         if (msg->msg_namelen) {
1694                 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP;
1695                 goto out;
1696         }
1697
1698         /* Send data only if both sides are not shutdown in the direction. */
1699         if (sk->sk_shutdown & SEND_SHUTDOWN ||
1700             vsk->peer_shutdown & RCV_SHUTDOWN) {
1701                 err = -EPIPE;
1702                 goto out;
1703         }
1704
1705         if (!transport || sk->sk_state != TCP_ESTABLISHED ||
1706             !vsock_addr_bound(&vsk->local_addr)) {
1707                 err = -ENOTCONN;
1708                 goto out;
1709         }
1710
1711         if (!vsock_addr_bound(&vsk->remote_addr)) {
1712                 err = -EDESTADDRREQ;
1713                 goto out;
1714         }
1715
1716         /* Wait for room in the produce queue to enqueue our user's data. */
1717         timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1718
1719         err = transport->notify_send_init(vsk, &send_data);
1720         if (err < 0)
1721                 goto out;
1722
1723         while (total_written < len) {
1724                 ssize_t written;
1725
1726                 add_wait_queue(sk_sleep(sk), &wait);
1727                 while (vsock_stream_has_space(vsk) == 0 &&
1728                        sk->sk_err == 0 &&
1729                        !(sk->sk_shutdown & SEND_SHUTDOWN) &&
1730                        !(vsk->peer_shutdown & RCV_SHUTDOWN)) {
1731
1732                         /* Don't wait for non-blocking sockets. */
1733                         if (timeout == 0) {
1734                                 err = -EAGAIN;
1735                                 remove_wait_queue(sk_sleep(sk), &wait);
1736                                 goto out_err;
1737                         }
1738
1739                         err = transport->notify_send_pre_block(vsk, &send_data);
1740                         if (err < 0) {
1741                                 remove_wait_queue(sk_sleep(sk), &wait);
1742                                 goto out_err;
1743                         }
1744
1745                         release_sock(sk);
1746                         timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout);
1747                         lock_sock(sk);
1748                         if (signal_pending(current)) {
1749                                 err = sock_intr_errno(timeout);
1750                                 remove_wait_queue(sk_sleep(sk), &wait);
1751                                 goto out_err;
1752                         } else if (timeout == 0) {
1753                                 err = -EAGAIN;
1754                                 remove_wait_queue(sk_sleep(sk), &wait);
1755                                 goto out_err;
1756                         }
1757                 }
1758                 remove_wait_queue(sk_sleep(sk), &wait);
1759
1760                 /* These checks occur both as part of and after the loop
1761                  * conditional since we need to check before and after
1762                  * sleeping.
1763                  */
1764                 if (sk->sk_err) {
1765                         err = -sk->sk_err;
1766                         goto out_err;
1767                 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) ||
1768                            (vsk->peer_shutdown & RCV_SHUTDOWN)) {
1769                         err = -EPIPE;
1770                         goto out_err;
1771                 }
1772
1773                 err = transport->notify_send_pre_enqueue(vsk, &send_data);
1774                 if (err < 0)
1775                         goto out_err;
1776
1777                 /* Note that enqueue will only write as many bytes as are free
1778                  * in the produce queue, so we don't need to ensure len is
1779                  * smaller than the queue size.  It is the caller's
1780                  * responsibility to check how many bytes we were able to send.
1781                  */
1782
1783                 written = transport->stream_enqueue(
1784                                 vsk, msg,
1785                                 len - total_written);
1786                 if (written < 0) {
1787                         err = -ENOMEM;
1788                         goto out_err;
1789                 }
1790
1791                 total_written += written;
1792
1793                 err = transport->notify_send_post_enqueue(
1794                                 vsk, written, &send_data);
1795                 if (err < 0)
1796                         goto out_err;
1797
1798         }
1799
1800 out_err:
1801         if (total_written > 0)
1802                 err = total_written;
1803 out:
1804         release_sock(sk);
1805         return err;
1806 }
1807
1808
1809 static int
1810 vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1811                      int flags)
1812 {
1813         struct sock *sk;
1814         struct vsock_sock *vsk;
1815         const struct vsock_transport *transport;
1816         int err;
1817         size_t target;
1818         ssize_t copied;
1819         long timeout;
1820         struct vsock_transport_recv_notify_data recv_data;
1821
1822         DEFINE_WAIT(wait);
1823
1824         sk = sock->sk;
1825         vsk = vsock_sk(sk);
1826         transport = vsk->transport;
1827         err = 0;
1828
1829         lock_sock(sk);
1830
1831         if (!transport || sk->sk_state != TCP_ESTABLISHED) {
1832                 /* Recvmsg is supposed to return 0 if a peer performs an
1833                  * orderly shutdown. Differentiate between that case and when a
1834                  * peer has not connected or a local shutdown occured with the
1835                  * SOCK_DONE flag.
1836                  */
1837                 if (sock_flag(sk, SOCK_DONE))
1838                         err = 0;
1839                 else
1840                         err = -ENOTCONN;
1841
1842                 goto out;
1843         }
1844
1845         if (flags & MSG_OOB) {
1846                 err = -EOPNOTSUPP;
1847                 goto out;
1848         }
1849
1850         /* We don't check peer_shutdown flag here since peer may actually shut
1851          * down, but there can be data in the queue that a local socket can
1852          * receive.
1853          */
1854         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1855                 err = 0;
1856                 goto out;
1857         }
1858
1859         /* It is valid on Linux to pass in a zero-length receive buffer.  This
1860          * is not an error.  We may as well bail out now.
1861          */
1862         if (!len) {
1863                 err = 0;
1864                 goto out;
1865         }
1866
1867         /* We must not copy less than target bytes into the user's buffer
1868          * before returning successfully, so we wait for the consume queue to
1869          * have that much data to consume before dequeueing.  Note that this
1870          * makes it impossible to handle cases where target is greater than the
1871          * queue size.
1872          */
1873         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1874         if (target >= transport->stream_rcvhiwat(vsk)) {
1875                 err = -ENOMEM;
1876                 goto out;
1877         }
1878         timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1879         copied = 0;
1880
1881         err = transport->notify_recv_init(vsk, target, &recv_data);
1882         if (err < 0)
1883                 goto out;
1884
1885
1886         while (1) {
1887                 s64 ready;
1888
1889                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1890                 ready = vsock_stream_has_data(vsk);
1891
1892                 if (ready == 0) {
1893                         if (sk->sk_err != 0 ||
1894                             (sk->sk_shutdown & RCV_SHUTDOWN) ||
1895                             (vsk->peer_shutdown & SEND_SHUTDOWN)) {
1896                                 finish_wait(sk_sleep(sk), &wait);
1897                                 break;
1898                         }
1899                         /* Don't wait for non-blocking sockets. */
1900                         if (timeout == 0) {
1901                                 err = -EAGAIN;
1902                                 finish_wait(sk_sleep(sk), &wait);
1903                                 break;
1904                         }
1905
1906                         err = transport->notify_recv_pre_block(
1907                                         vsk, target, &recv_data);
1908                         if (err < 0) {
1909                                 finish_wait(sk_sleep(sk), &wait);
1910                                 break;
1911                         }
1912                         release_sock(sk);
1913                         timeout = schedule_timeout(timeout);
1914                         lock_sock(sk);
1915
1916                         if (signal_pending(current)) {
1917                                 err = sock_intr_errno(timeout);
1918                                 finish_wait(sk_sleep(sk), &wait);
1919                                 break;
1920                         } else if (timeout == 0) {
1921                                 err = -EAGAIN;
1922                                 finish_wait(sk_sleep(sk), &wait);
1923                                 break;
1924                         }
1925                 } else {
1926                         ssize_t read;
1927
1928                         finish_wait(sk_sleep(sk), &wait);
1929
1930                         if (ready < 0) {
1931                                 /* Invalid queue pair content. XXX This should
1932                                 * be changed to a connection reset in a later
1933                                 * change.
1934                                 */
1935
1936                                 err = -ENOMEM;
1937                                 goto out;
1938                         }
1939
1940                         err = transport->notify_recv_pre_dequeue(
1941                                         vsk, target, &recv_data);
1942                         if (err < 0)
1943                                 break;
1944
1945                         read = transport->stream_dequeue(
1946                                         vsk, msg,
1947                                         len - copied, flags);
1948                         if (read < 0) {
1949                                 err = -ENOMEM;
1950                                 break;
1951                         }
1952
1953                         copied += read;
1954
1955                         err = transport->notify_recv_post_dequeue(
1956                                         vsk, target, read,
1957                                         !(flags & MSG_PEEK), &recv_data);
1958                         if (err < 0)
1959                                 goto out;
1960
1961                         if (read >= target || flags & MSG_PEEK)
1962                                 break;
1963
1964                         target -= read;
1965                 }
1966         }
1967
1968         if (sk->sk_err)
1969                 err = -sk->sk_err;
1970         else if (sk->sk_shutdown & RCV_SHUTDOWN)
1971                 err = 0;
1972
1973         if (copied > 0)
1974                 err = copied;
1975
1976 out:
1977         release_sock(sk);
1978         return err;
1979 }
1980
1981 static const struct proto_ops vsock_stream_ops = {
1982         .family = PF_VSOCK,
1983         .owner = THIS_MODULE,
1984         .release = vsock_release,
1985         .bind = vsock_bind,
1986         .connect = vsock_stream_connect,
1987         .socketpair = sock_no_socketpair,
1988         .accept = vsock_accept,
1989         .getname = vsock_getname,
1990         .poll = vsock_poll,
1991         .ioctl = sock_no_ioctl,
1992         .listen = vsock_listen,
1993         .shutdown = vsock_shutdown,
1994         .setsockopt = vsock_stream_setsockopt,
1995         .getsockopt = vsock_stream_getsockopt,
1996         .sendmsg = vsock_stream_sendmsg,
1997         .recvmsg = vsock_stream_recvmsg,
1998         .mmap = sock_no_mmap,
1999         .sendpage = sock_no_sendpage,
2000 };
2001
2002 static int vsock_create(struct net *net, struct socket *sock,
2003                         int protocol, int kern)
2004 {
2005         struct vsock_sock *vsk;
2006         struct sock *sk;
2007         int ret;
2008
2009         if (!sock)
2010                 return -EINVAL;
2011
2012         if (protocol && protocol != PF_VSOCK)
2013                 return -EPROTONOSUPPORT;
2014
2015         switch (sock->type) {
2016         case SOCK_DGRAM:
2017                 sock->ops = &vsock_dgram_ops;
2018                 break;
2019         case SOCK_STREAM:
2020                 sock->ops = &vsock_stream_ops;
2021                 break;
2022         default:
2023                 return -ESOCKTNOSUPPORT;
2024         }
2025
2026         sock->state = SS_UNCONNECTED;
2027
2028         sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern);
2029         if (!sk)
2030                 return -ENOMEM;
2031
2032         vsk = vsock_sk(sk);
2033
2034         if (sock->type == SOCK_DGRAM) {
2035                 ret = vsock_assign_transport(vsk, NULL);
2036                 if (ret < 0) {
2037                         sock_put(sk);
2038                         return ret;
2039                 }
2040         }
2041
2042         vsock_insert_unbound(vsk);
2043
2044         return 0;
2045 }
2046
2047 static const struct net_proto_family vsock_family_ops = {
2048         .family = AF_VSOCK,
2049         .create = vsock_create,
2050         .owner = THIS_MODULE,
2051 };
2052
2053 static long vsock_dev_do_ioctl(struct file *filp,
2054                                unsigned int cmd, void __user *ptr)
2055 {
2056         u32 __user *p = ptr;
2057         u32 cid = VMADDR_CID_ANY;
2058         int retval = 0;
2059
2060         switch (cmd) {
2061         case IOCTL_VM_SOCKETS_GET_LOCAL_CID:
2062                 /* To be compatible with the VMCI behavior, we prioritize the
2063                  * guest CID instead of well-know host CID (VMADDR_CID_HOST).
2064                  */
2065                 if (transport_g2h)
2066                         cid = transport_g2h->get_local_cid();
2067                 else if (transport_h2g)
2068                         cid = transport_h2g->get_local_cid();
2069
2070                 if (put_user(cid, p) != 0)
2071                         retval = -EFAULT;
2072                 break;
2073
2074         default:
2075                 pr_err("Unknown ioctl %d\n", cmd);
2076                 retval = -EINVAL;
2077         }
2078
2079         return retval;
2080 }
2081
2082 static long vsock_dev_ioctl(struct file *filp,
2083                             unsigned int cmd, unsigned long arg)
2084 {
2085         return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg);
2086 }
2087
2088 #ifdef CONFIG_COMPAT
2089 static long vsock_dev_compat_ioctl(struct file *filp,
2090                                    unsigned int cmd, unsigned long arg)
2091 {
2092         return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg));
2093 }
2094 #endif
2095
2096 static const struct file_operations vsock_device_ops = {
2097         .owner          = THIS_MODULE,
2098         .unlocked_ioctl = vsock_dev_ioctl,
2099 #ifdef CONFIG_COMPAT
2100         .compat_ioctl   = vsock_dev_compat_ioctl,
2101 #endif
2102         .open           = nonseekable_open,
2103 };
2104
2105 static struct miscdevice vsock_device = {
2106         .name           = "vsock",
2107         .fops           = &vsock_device_ops,
2108 };
2109
2110 static int __init vsock_init(void)
2111 {
2112         int err = 0;
2113
2114         vsock_init_tables();
2115
2116         vsock_proto.owner = THIS_MODULE;
2117         vsock_device.minor = MISC_DYNAMIC_MINOR;
2118         err = misc_register(&vsock_device);
2119         if (err) {
2120                 pr_err("Failed to register misc device\n");
2121                 goto err_reset_transport;
2122         }
2123
2124         err = proto_register(&vsock_proto, 1);  /* we want our slab */
2125         if (err) {
2126                 pr_err("Cannot register vsock protocol\n");
2127                 goto err_deregister_misc;
2128         }
2129
2130         err = sock_register(&vsock_family_ops);
2131         if (err) {
2132                 pr_err("could not register af_vsock (%d) address family: %d\n",
2133                        AF_VSOCK, err);
2134                 goto err_unregister_proto;
2135         }
2136
2137         return 0;
2138
2139 err_unregister_proto:
2140         proto_unregister(&vsock_proto);
2141 err_deregister_misc:
2142         misc_deregister(&vsock_device);
2143 err_reset_transport:
2144         return err;
2145 }
2146
2147 static void __exit vsock_exit(void)
2148 {
2149         misc_deregister(&vsock_device);
2150         sock_unregister(AF_VSOCK);
2151         proto_unregister(&vsock_proto);
2152 }
2153
2154 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk)
2155 {
2156         return vsk->transport;
2157 }
2158 EXPORT_SYMBOL_GPL(vsock_core_get_transport);
2159
2160 int vsock_core_register(const struct vsock_transport *t, int features)
2161 {
2162         const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local;
2163         int err = mutex_lock_interruptible(&vsock_register_mutex);
2164
2165         if (err)
2166                 return err;
2167
2168         t_h2g = transport_h2g;
2169         t_g2h = transport_g2h;
2170         t_dgram = transport_dgram;
2171         t_local = transport_local;
2172
2173         if (features & VSOCK_TRANSPORT_F_H2G) {
2174                 if (t_h2g) {
2175                         err = -EBUSY;
2176                         goto err_busy;
2177                 }
2178                 t_h2g = t;
2179         }
2180
2181         if (features & VSOCK_TRANSPORT_F_G2H) {
2182                 if (t_g2h) {
2183                         err = -EBUSY;
2184                         goto err_busy;
2185                 }
2186                 t_g2h = t;
2187         }
2188
2189         if (features & VSOCK_TRANSPORT_F_DGRAM) {
2190                 if (t_dgram) {
2191                         err = -EBUSY;
2192                         goto err_busy;
2193                 }
2194                 t_dgram = t;
2195         }
2196
2197         if (features & VSOCK_TRANSPORT_F_LOCAL) {
2198                 if (t_local) {
2199                         err = -EBUSY;
2200                         goto err_busy;
2201                 }
2202                 t_local = t;
2203         }
2204
2205         transport_h2g = t_h2g;
2206         transport_g2h = t_g2h;
2207         transport_dgram = t_dgram;
2208         transport_local = t_local;
2209
2210 err_busy:
2211         mutex_unlock(&vsock_register_mutex);
2212         return err;
2213 }
2214 EXPORT_SYMBOL_GPL(vsock_core_register);
2215
2216 void vsock_core_unregister(const struct vsock_transport *t)
2217 {
2218         mutex_lock(&vsock_register_mutex);
2219
2220         if (transport_h2g == t)
2221                 transport_h2g = NULL;
2222
2223         if (transport_g2h == t)
2224                 transport_g2h = NULL;
2225
2226         if (transport_dgram == t)
2227                 transport_dgram = NULL;
2228
2229         if (transport_local == t)
2230                 transport_local = NULL;
2231
2232         mutex_unlock(&vsock_register_mutex);
2233 }
2234 EXPORT_SYMBOL_GPL(vsock_core_unregister);
2235
2236 module_init(vsock_init);
2237 module_exit(vsock_exit);
2238
2239 MODULE_AUTHOR("VMware, Inc.");
2240 MODULE_DESCRIPTION("VMware Virtual Socket Family");
2241 MODULE_VERSION("1.0.2.0-k");
2242 MODULE_LICENSE("GPL v2");