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 or h2g is not loaded or remote flags field
 425  *    includes VMADDR_FLAG_TO_HOST flag value, will use guest->host transport;
 426  *  - remote CID > VMADDR_CID_HOST will use host->guest transport;
 427  */
 428 int vsock_assign_transport(struct vsock_sock *vsk, struct vsock_sock *psk)
 429 {
 430         const struct vsock_transport *new_transport;
 431         struct sock *sk = sk_vsock(vsk);
 432         unsigned int remote_cid = vsk->remote_addr.svm_cid;
 433         __u8 remote_flags;
 434         int ret;
 435
 436         /* If the packet is coming with the source and destination CIDs higher
 437          * than VMADDR_CID_HOST, then a vsock channel where all the packets are
 438          * forwarded to the host should be established. Then the host will
 439          * need to forward the packets to the guest.
 440          *
 441          * The flag is set on the (listen) receive path (psk is not NULL). On
 442          * the connect path the flag can be set by the user space application.
 443          */
 444         if (psk && vsk->local_addr.svm_cid > VMADDR_CID_HOST &&
 445             vsk->remote_addr.svm_cid > VMADDR_CID_HOST)
 446                 vsk->remote_addr.svm_flags |= VMADDR_FLAG_TO_HOST;
 447
 448         remote_flags = vsk->remote_addr.svm_flags;
 449
 450         switch (sk->sk_type) {
 451         case SOCK_DGRAM:
 452                 new_transport = transport_dgram;
 453                 break;
 454         case SOCK_STREAM:
 455                 if (vsock_use_local_transport(remote_cid))
 456                         new_transport = transport_local;
 457                 else if (remote_cid <= VMADDR_CID_HOST || !transport_h2g ||
 458                          (remote_flags & VMADDR_FLAG_TO_HOST))
 459                         new_transport = transport_g2h;
 460                 else
 461                         new_transport = transport_h2g;
 462                 break;
 463         default:
 464                 return -ESOCKTNOSUPPORT;
 465         }
 466
 467         if (vsk->transport) {
 468                 if (vsk->transport == new_transport)
 469                         return 0;
 470
 471                 /* transport->release() must be called with sock lock acquired.
 472                  * This path can only be taken during vsock_stream_connect(),
 473                  * where we have already held the sock lock.
 474                  * In the other cases, this function is called on a new socket
 475                  * which is not assigned to any transport.
 476                  */
 477                 vsk->transport->release(vsk);
 478                 vsock_deassign_transport(vsk);
 479         }
 480
 481         /* We increase the module refcnt to prevent the transport unloading
 482          * while there are open sockets assigned to it.
 483          */
 484         if (!new_transport || !try_module_get(new_transport->module))
 485                 return -ENODEV;
 486
 487         ret = new_transport->init(vsk, psk);
 488         if (ret) {
 489                 module_put(new_transport->module);
 490                 return ret;
 491         }
 492
 493         vsk->transport = new_transport;
 494
 495         return 0;
 496 }
 497 EXPORT_SYMBOL_GPL(vsock_assign_transport);
 498
 499 bool vsock_find_cid(unsigned int cid)
 500 {
 501         if (transport_g2h && cid == transport_g2h->get_local_cid())
 502                 return true;
 503
 504         if (transport_h2g && cid == VMADDR_CID_HOST)
 505                 return true;
 506
 507         if (transport_local && cid == VMADDR_CID_LOCAL)
 508                 return true;
 509
 510         return false;
 511 }
 512 EXPORT_SYMBOL_GPL(vsock_find_cid);
 513
 514 static struct sock *vsock_dequeue_accept(struct sock *listener)
 515 {
 516         struct vsock_sock *vlistener;
 517         struct vsock_sock *vconnected;
 518
 519         vlistener = vsock_sk(listener);
 520
 521         if (list_empty(&vlistener->accept_queue))
 522                 return NULL;
 523
 524         vconnected = list_entry(vlistener->accept_queue.next,
 525                                 struct vsock_sock, accept_queue);
 526
 527         list_del_init(&vconnected->accept_queue);
 528         sock_put(listener);
 529         /* The caller will need a reference on the connected socket so we let
 530          * it call sock_put().
 531          */
 532
 533         return sk_vsock(vconnected);
 534 }
 535
 536 static bool vsock_is_accept_queue_empty(struct sock *sk)
 537 {
 538         struct vsock_sock *vsk = vsock_sk(sk);
 539         return list_empty(&vsk->accept_queue);
 540 }
 541
 542 static bool vsock_is_pending(struct sock *sk)
 543 {
 544         struct vsock_sock *vsk = vsock_sk(sk);
 545         return !list_empty(&vsk->pending_links);
 546 }
 547
 548 static int vsock_send_shutdown(struct sock *sk, int mode)
 549 {
 550         struct vsock_sock *vsk = vsock_sk(sk);
 551
 552         if (!vsk->transport)
 553                 return -ENODEV;
 554
 555         return vsk->transport->shutdown(vsk, mode);
 556 }
 557
 558 static void vsock_pending_work(struct work_struct *work)
 559 {
 560         struct sock *sk;
 561         struct sock *listener;
 562         struct vsock_sock *vsk;
 563         bool cleanup;
 564
 565         vsk = container_of(work, struct vsock_sock, pending_work.work);
 566         sk = sk_vsock(vsk);
 567         listener = vsk->listener;
 568         cleanup = true;
 569
 570         lock_sock(listener);
 571         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
 572
 573         if (vsock_is_pending(sk)) {
 574                 vsock_remove_pending(listener, sk);
 575
 576                 sk_acceptq_removed(listener);
 577         } else if (!vsk->rejected) {
 578                 /* We are not on the pending list and accept() did not reject
 579                  * us, so we must have been accepted by our user process.  We
 580                  * just need to drop our references to the sockets and be on
 581                  * our way.
 582                  */
 583                 cleanup = false;
 584                 goto out;
 585         }
 586
 587         /* We need to remove ourself from the global connected sockets list so
 588          * incoming packets can't find this socket, and to reduce the reference
 589          * count.
 590          */
 591         vsock_remove_connected(vsk);
 592
 593         sk->sk_state = TCP_CLOSE;
 594
 595 out:
 596         release_sock(sk);
 597         release_sock(listener);
 598         if (cleanup)
 599                 sock_put(sk);
 600
 601         sock_put(sk);
 602         sock_put(listener);
 603 }
 604
 605 /**** SOCKET OPERATIONS ****/
 606
 607 static int __vsock_bind_stream(struct vsock_sock *vsk,
 608                                struct sockaddr_vm *addr)
 609 {
 610         static u32 port;
 611         struct sockaddr_vm new_addr;
 612
 613         if (!port)
 614                 port = LAST_RESERVED_PORT + 1 +
 615                         prandom_u32_max(U32_MAX - LAST_RESERVED_PORT);
 616
 617         vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port);
 618
 619         if (addr->svm_port == VMADDR_PORT_ANY) {
 620                 bool found = false;
 621                 unsigned int i;
 622
 623                 for (i = 0; i < MAX_PORT_RETRIES; i++) {
 624                         if (port <= LAST_RESERVED_PORT)
 625                                 port = LAST_RESERVED_PORT + 1;
 626
 627                         new_addr.svm_port = port++;
 628
 629                         if (!__vsock_find_bound_socket(&new_addr)) {
 630                                 found = true;
 631                                 break;
 632                         }
 633                 }
 634
 635                 if (!found)
 636                         return -EADDRNOTAVAIL;
 637         } else {
 638                 /* If port is in reserved range, ensure caller
 639                  * has necessary privileges.
 640                  */
 641                 if (addr->svm_port <= LAST_RESERVED_PORT &&
 642                     !capable(CAP_NET_BIND_SERVICE)) {
 643                         return -EACCES;
 644                 }
 645
 646                 if (__vsock_find_bound_socket(&new_addr))
 647                         return -EADDRINUSE;
 648         }
 649
 650         vsock_addr_init(&vsk->local_addr, new_addr.svm_cid, new_addr.svm_port);
 651
 652         /* Remove stream sockets from the unbound list and add them to the hash
 653          * table for easy lookup by its address.  The unbound list is simply an
 654          * extra entry at the end of the hash table, a trick used by AF_UNIX.
 655          */
 656         __vsock_remove_bound(vsk);
 657         __vsock_insert_bound(vsock_bound_sockets(&vsk->local_addr), vsk);
 658
 659         return 0;
 660 }
 661
 662 static int __vsock_bind_dgram(struct vsock_sock *vsk,
 663                               struct sockaddr_vm *addr)
 664 {
 665         return vsk->transport->dgram_bind(vsk, addr);
 666 }
 667
 668 static int __vsock_bind(struct sock *sk, struct sockaddr_vm *addr)
 669 {
 670         struct vsock_sock *vsk = vsock_sk(sk);
 671         int retval;
 672
 673         /* First ensure this socket isn't already bound. */
 674         if (vsock_addr_bound(&vsk->local_addr))
 675                 return -EINVAL;
 676
 677         /* Now bind to the provided address or select appropriate values if
 678          * none are provided (VMADDR_CID_ANY and VMADDR_PORT_ANY).  Note that
 679          * like AF_INET prevents binding to a non-local IP address (in most
 680          * cases), we only allow binding to a local CID.
 681          */
 682         if (addr->svm_cid != VMADDR_CID_ANY && !vsock_find_cid(addr->svm_cid))
 683                 return -EADDRNOTAVAIL;
 684
 685         switch (sk->sk_socket->type) {
 686         case SOCK_STREAM:
 687                 spin_lock_bh(&vsock_table_lock);
 688                 retval = __vsock_bind_stream(vsk, addr);
 689                 spin_unlock_bh(&vsock_table_lock);
 690                 break;
 691
 692         case SOCK_DGRAM:
 693                 retval = __vsock_bind_dgram(vsk, addr);
 694                 break;
 695
 696         default:
 697                 retval = -EINVAL;
 698                 break;
 699         }
 700
 701         return retval;
 702 }
 703
 704 static void vsock_connect_timeout(struct work_struct *work);
 705
 706 static struct sock *__vsock_create(struct net *net,
 707                                    struct socket *sock,
 708                                    struct sock *parent,
 709                                    gfp_t priority,
 710                                    unsigned short type,
 711                                    int kern)
 712 {
 713         struct sock *sk;
 714         struct vsock_sock *psk;
 715         struct vsock_sock *vsk;
 716
 717         sk = sk_alloc(net, AF_VSOCK, priority, &vsock_proto, kern);
 718         if (!sk)
 719                 return NULL;
 720
 721         sock_init_data(sock, sk);
 722
 723         /* sk->sk_type is normally set in sock_init_data, but only if sock is
 724          * non-NULL. We make sure that our sockets always have a type by
 725          * setting it here if needed.
 726          */
 727         if (!sock)
 728                 sk->sk_type = type;
 729
 730         vsk = vsock_sk(sk);
 731         vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 732         vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 733
 734         sk->sk_destruct = vsock_sk_destruct;
 735         sk->sk_backlog_rcv = vsock_queue_rcv_skb;
 736         sock_reset_flag(sk, SOCK_DONE);
 737
 738         INIT_LIST_HEAD(&vsk->bound_table);
 739         INIT_LIST_HEAD(&vsk->connected_table);
 740         vsk->listener = NULL;
 741         INIT_LIST_HEAD(&vsk->pending_links);
 742         INIT_LIST_HEAD(&vsk->accept_queue);
 743         vsk->rejected = false;
 744         vsk->sent_request = false;
 745         vsk->ignore_connecting_rst = false;
 746         vsk->peer_shutdown = 0;
 747         INIT_DELAYED_WORK(&vsk->connect_work, vsock_connect_timeout);
 748         INIT_DELAYED_WORK(&vsk->pending_work, vsock_pending_work);
 749
 750         psk = parent ? vsock_sk(parent) : NULL;
 751         if (parent) {
 752                 vsk->trusted = psk->trusted;
 753                 vsk->owner = get_cred(psk->owner);
 754                 vsk->connect_timeout = psk->connect_timeout;
 755                 vsk->buffer_size = psk->buffer_size;
 756                 vsk->buffer_min_size = psk->buffer_min_size;
 757                 vsk->buffer_max_size = psk->buffer_max_size;
 758         } else {
 759                 vsk->trusted = ns_capable_noaudit(&init_user_ns, CAP_NET_ADMIN);
 760                 vsk->owner = get_current_cred();
 761                 vsk->connect_timeout = VSOCK_DEFAULT_CONNECT_TIMEOUT;
 762                 vsk->buffer_size = VSOCK_DEFAULT_BUFFER_SIZE;
 763                 vsk->buffer_min_size = VSOCK_DEFAULT_BUFFER_MIN_SIZE;
 764                 vsk->buffer_max_size = VSOCK_DEFAULT_BUFFER_MAX_SIZE;
 765         }
 766
 767         return sk;
 768 }
 769
 770 static void __vsock_release(struct sock *sk, int level)
 771 {
 772         if (sk) {
 773                 struct sock *pending;
 774                 struct vsock_sock *vsk;
 775
 776                 vsk = vsock_sk(sk);
 777                 pending = NULL; /* Compiler warning. */
 778
 779                 /* When "level" is SINGLE_DEPTH_NESTING, use the nested
 780                  * version to avoid the warning "possible recursive locking
 781                  * detected". When "level" is 0, lock_sock_nested(sk, level)
 782                  * is the same as lock_sock(sk).
 783                  */
 784                 lock_sock_nested(sk, level);
 785
 786                 if (vsk->transport)
 787                         vsk->transport->release(vsk);
 788                 else if (sk->sk_type == SOCK_STREAM)
 789                         vsock_remove_sock(vsk);
 790
 791                 sock_orphan(sk);
 792                 sk->sk_shutdown = SHUTDOWN_MASK;
 793
 794                 skb_queue_purge(&sk->sk_receive_queue);
 795
 796                 /* Clean up any sockets that never were accepted. */
 797                 while ((pending = vsock_dequeue_accept(sk)) != NULL) {
 798                         __vsock_release(pending, SINGLE_DEPTH_NESTING);
 799                         sock_put(pending);
 800                 }
 801
 802                 release_sock(sk);
 803                 sock_put(sk);
 804         }
 805 }
 806
 807 static void vsock_sk_destruct(struct sock *sk)
 808 {
 809         struct vsock_sock *vsk = vsock_sk(sk);
 810
 811         vsock_deassign_transport(vsk);
 812
 813         /* When clearing these addresses, there's no need to set the family and
 814          * possibly register the address family with the kernel.
 815          */
 816         vsock_addr_init(&vsk->local_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 817         vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY, VMADDR_PORT_ANY);
 818
 819         put_cred(vsk->owner);
 820 }
 821
 822 static int vsock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
 823 {
 824         int err;
 825
 826         err = sock_queue_rcv_skb(sk, skb);
 827         if (err)
 828                 kfree_skb(skb);
 829
 830         return err;
 831 }
 832
 833 struct sock *vsock_create_connected(struct sock *parent)
 834 {
 835         return __vsock_create(sock_net(parent), NULL, parent, GFP_KERNEL,
 836                               parent->sk_type, 0);
 837 }
 838 EXPORT_SYMBOL_GPL(vsock_create_connected);
 839
 840 s64 vsock_stream_has_data(struct vsock_sock *vsk)
 841 {
 842         return vsk->transport->stream_has_data(vsk);
 843 }
 844 EXPORT_SYMBOL_GPL(vsock_stream_has_data);
 845
 846 s64 vsock_stream_has_space(struct vsock_sock *vsk)
 847 {
 848         return vsk->transport->stream_has_space(vsk);
 849 }
 850 EXPORT_SYMBOL_GPL(vsock_stream_has_space);
 851
 852 static int vsock_release(struct socket *sock)
 853 {
 854         __vsock_release(sock->sk, 0);
 855         sock->sk = NULL;
 856         sock->state = SS_FREE;
 857
 858         return 0;
 859 }
 860
 861 static int
 862 vsock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
 863 {
 864         int err;
 865         struct sock *sk;
 866         struct sockaddr_vm *vm_addr;
 867
 868         sk = sock->sk;
 869
 870         if (vsock_addr_cast(addr, addr_len, &vm_addr) != 0)
 871                 return -EINVAL;
 872
 873         lock_sock(sk);
 874         err = __vsock_bind(sk, vm_addr);
 875         release_sock(sk);
 876
 877         return err;
 878 }
 879
 880 static int vsock_getname(struct socket *sock,
 881                          struct sockaddr *addr, int peer)
 882 {
 883         int err;
 884         struct sock *sk;
 885         struct vsock_sock *vsk;
 886         struct sockaddr_vm *vm_addr;
 887
 888         sk = sock->sk;
 889         vsk = vsock_sk(sk);
 890         err = 0;
 891
 892         lock_sock(sk);
 893
 894         if (peer) {
 895                 if (sock->state != SS_CONNECTED) {
 896                         err = -ENOTCONN;
 897                         goto out;
 898                 }
 899                 vm_addr = &vsk->remote_addr;
 900         } else {
 901                 vm_addr = &vsk->local_addr;
 902         }
 903
 904         if (!vm_addr) {
 905                 err = -EINVAL;
 906                 goto out;
 907         }
 908
 909         /* sys_getsockname() and sys_getpeername() pass us a
 910          * MAX_SOCK_ADDR-sized buffer and don't set addr_len.  Unfortunately
 911          * that macro is defined in socket.c instead of .h, so we hardcode its
 912          * value here.
 913          */
 914         BUILD_BUG_ON(sizeof(*vm_addr) > 128);
 915         memcpy(addr, vm_addr, sizeof(*vm_addr));
 916         err = sizeof(*vm_addr);
 917
 918 out:
 919         release_sock(sk);
 920         return err;
 921 }
 922
 923 static int vsock_shutdown(struct socket *sock, int mode)
 924 {
 925         int err;
 926         struct sock *sk;
 927
 928         /* User level uses SHUT_RD (0) and SHUT_WR (1), but the kernel uses
 929          * RCV_SHUTDOWN (1) and SEND_SHUTDOWN (2), so we must increment mode
 930          * here like the other address families do.  Note also that the
 931          * increment makes SHUT_RDWR (2) into RCV_SHUTDOWN | SEND_SHUTDOWN (3),
 932          * which is what we want.
 933          */
 934         mode++;
 935
 936         if ((mode & ~SHUTDOWN_MASK) || !mode)
 937                 return -EINVAL;
 938
 939         /* If this is a STREAM socket and it is not connected then bail out
 940          * immediately.  If it is a DGRAM socket then we must first kick the
 941          * socket so that it wakes up from any sleeping calls, for example
 942          * recv(), and then afterwards return the error.
 943          */
 944
 945         sk = sock->sk;
 946         if (sock->state == SS_UNCONNECTED) {
 947                 err = -ENOTCONN;
 948                 if (sk->sk_type == SOCK_STREAM)
 949                         return err;
 950         } else {
 951                 sock->state = SS_DISCONNECTING;
 952                 err = 0;
 953         }
 954
 955         /* Receive and send shutdowns are treated alike. */
 956         mode = mode & (RCV_SHUTDOWN | SEND_SHUTDOWN);
 957         if (mode) {
 958                 lock_sock(sk);
 959                 sk->sk_shutdown |= mode;
 960                 sk->sk_state_change(sk);
 961                 release_sock(sk);
 962
 963                 if (sk->sk_type == SOCK_STREAM) {
 964                         sock_reset_flag(sk, SOCK_DONE);
 965                         vsock_send_shutdown(sk, mode);
 966                 }
 967         }
 968
 969         return err;
 970 }
 971
 972 static __poll_t vsock_poll(struct file *file, struct socket *sock,
 973                                poll_table *wait)
 974 {
 975         struct sock *sk;
 976         __poll_t mask;
 977         struct vsock_sock *vsk;
 978
 979         sk = sock->sk;
 980         vsk = vsock_sk(sk);
 981
 982         poll_wait(file, sk_sleep(sk), wait);
 983         mask = 0;
 984
 985         if (sk->sk_err)
 986                 /* Signify that there has been an error on this socket. */
 987                 mask |= EPOLLERR;
 988
 989         /* INET sockets treat local write shutdown and peer write shutdown as a
 990          * case of EPOLLHUP set.
 991          */
 992         if ((sk->sk_shutdown == SHUTDOWN_MASK) ||
 993             ((sk->sk_shutdown & SEND_SHUTDOWN) &&
 994              (vsk->peer_shutdown & SEND_SHUTDOWN))) {
 995                 mask |= EPOLLHUP;
 996         }
 997
 998         if (sk->sk_shutdown & RCV_SHUTDOWN ||
 999             vsk->peer_shutdown & SEND_SHUTDOWN) {
1000                 mask |= EPOLLRDHUP;
1001         }
1002
1003         if (sock->type == SOCK_DGRAM) {
1004                 /* For datagram sockets we can read if there is something in
1005                  * the queue and write as long as the socket isn't shutdown for
1006                  * sending.
1007                  */
1008                 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) ||
1009                     (sk->sk_shutdown & RCV_SHUTDOWN)) {
1010                         mask |= EPOLLIN | EPOLLRDNORM;
1011                 }
1012
1013                 if (!(sk->sk_shutdown & SEND_SHUTDOWN))
1014                         mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
1015
1016         } else if (sock->type == SOCK_STREAM) {
1017                 const struct vsock_transport *transport = vsk->transport;
1018                 lock_sock(sk);
1019
1020                 /* Listening sockets that have connections in their accept
1021                  * queue can be read.
1022                  */
1023                 if (sk->sk_state == TCP_LISTEN
1024                     && !vsock_is_accept_queue_empty(sk))
1025                         mask |= EPOLLIN | EPOLLRDNORM;
1026
1027                 /* If there is something in the queue then we can read. */
1028                 if (transport && transport->stream_is_active(vsk) &&
1029                     !(sk->sk_shutdown & RCV_SHUTDOWN)) {
1030                         bool data_ready_now = false;
1031                         int ret = transport->notify_poll_in(
1032                                         vsk, 1, &data_ready_now);
1033                         if (ret < 0) {
1034                                 mask |= EPOLLERR;
1035                         } else {
1036                                 if (data_ready_now)
1037                                         mask |= EPOLLIN | EPOLLRDNORM;
1038
1039                         }
1040                 }
1041
1042                 /* Sockets whose connections have been closed, reset, or
1043                  * terminated should also be considered read, and we check the
1044                  * shutdown flag for that.
1045                  */
1046                 if (sk->sk_shutdown & RCV_SHUTDOWN ||
1047                     vsk->peer_shutdown & SEND_SHUTDOWN) {
1048                         mask |= EPOLLIN | EPOLLRDNORM;
1049                 }
1050
1051                 /* Connected sockets that can produce data can be written. */
1052                 if (transport && sk->sk_state == TCP_ESTABLISHED) {
1053                         if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
1054                                 bool space_avail_now = false;
1055                                 int ret = transport->notify_poll_out(
1056                                                 vsk, 1, &space_avail_now);
1057                                 if (ret < 0) {
1058                                         mask |= EPOLLERR;
1059                                 } else {
1060                                         if (space_avail_now)
1061                                                 /* Remove EPOLLWRBAND since INET
1062                                                  * sockets are not setting it.
1063                                                  */
1064                                                 mask |= EPOLLOUT | EPOLLWRNORM;
1065
1066                                 }
1067                         }
1068                 }
1069
1070                 /* Simulate INET socket poll behaviors, which sets
1071                  * EPOLLOUT|EPOLLWRNORM when peer is closed and nothing to read,
1072                  * but local send is not shutdown.
1073                  */
1074                 if (sk->sk_state == TCP_CLOSE || sk->sk_state == TCP_CLOSING) {
1075                         if (!(sk->sk_shutdown & SEND_SHUTDOWN))
1076                                 mask |= EPOLLOUT | EPOLLWRNORM;
1077
1078                 }
1079
1080                 release_sock(sk);
1081         }
1082
1083         return mask;
1084 }
1085
1086 static int vsock_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
1087                                size_t len)
1088 {
1089         int err;
1090         struct sock *sk;
1091         struct vsock_sock *vsk;
1092         struct sockaddr_vm *remote_addr;
1093         const struct vsock_transport *transport;
1094
1095         if (msg->msg_flags & MSG_OOB)
1096                 return -EOPNOTSUPP;
1097
1098         /* For now, MSG_DONTWAIT is always assumed... */
1099         err = 0;
1100         sk = sock->sk;
1101         vsk = vsock_sk(sk);
1102         transport = vsk->transport;
1103
1104         lock_sock(sk);
1105
1106         err = vsock_auto_bind(vsk);
1107         if (err)
1108                 goto out;
1109
1110
1111         /* If the provided message contains an address, use that.  Otherwise
1112          * fall back on the socket's remote handle (if it has been connected).
1113          */
1114         if (msg->msg_name &&
1115             vsock_addr_cast(msg->msg_name, msg->msg_namelen,
1116                             &remote_addr) == 0) {
1117                 /* Ensure this address is of the right type and is a valid
1118                  * destination.
1119                  */
1120
1121                 if (remote_addr->svm_cid == VMADDR_CID_ANY)
1122                         remote_addr->svm_cid = transport->get_local_cid();
1123
1124                 if (!vsock_addr_bound(remote_addr)) {
1125                         err = -EINVAL;
1126                         goto out;
1127                 }
1128         } else if (sock->state == SS_CONNECTED) {
1129                 remote_addr = &vsk->remote_addr;
1130
1131                 if (remote_addr->svm_cid == VMADDR_CID_ANY)
1132                         remote_addr->svm_cid = transport->get_local_cid();
1133
1134                 /* XXX Should connect() or this function ensure remote_addr is
1135                  * bound?
1136                  */
1137                 if (!vsock_addr_bound(&vsk->remote_addr)) {
1138                         err = -EINVAL;
1139                         goto out;
1140                 }
1141         } else {
1142                 err = -EINVAL;
1143                 goto out;
1144         }
1145
1146         if (!transport->dgram_allow(remote_addr->svm_cid,
1147                                     remote_addr->svm_port)) {
1148                 err = -EINVAL;
1149                 goto out;
1150         }
1151
1152         err = transport->dgram_enqueue(vsk, remote_addr, msg, len);
1153
1154 out:
1155         release_sock(sk);
1156         return err;
1157 }
1158
1159 static int vsock_dgram_connect(struct socket *sock,
1160                                struct sockaddr *addr, int addr_len, int flags)
1161 {
1162         int err;
1163         struct sock *sk;
1164         struct vsock_sock *vsk;
1165         struct sockaddr_vm *remote_addr;
1166
1167         sk = sock->sk;
1168         vsk = vsock_sk(sk);
1169
1170         err = vsock_addr_cast(addr, addr_len, &remote_addr);
1171         if (err == -EAFNOSUPPORT && remote_addr->svm_family == AF_UNSPEC) {
1172                 lock_sock(sk);
1173                 vsock_addr_init(&vsk->remote_addr, VMADDR_CID_ANY,
1174                                 VMADDR_PORT_ANY);
1175                 sock->state = SS_UNCONNECTED;
1176                 release_sock(sk);
1177                 return 0;
1178         } else if (err != 0)
1179                 return -EINVAL;
1180
1181         lock_sock(sk);
1182
1183         err = vsock_auto_bind(vsk);
1184         if (err)
1185                 goto out;
1186
1187         if (!vsk->transport->dgram_allow(remote_addr->svm_cid,
1188                                          remote_addr->svm_port)) {
1189                 err = -EINVAL;
1190                 goto out;
1191         }
1192
1193         memcpy(&vsk->remote_addr, remote_addr, sizeof(vsk->remote_addr));
1194         sock->state = SS_CONNECTED;
1195
1196 out:
1197         release_sock(sk);
1198         return err;
1199 }
1200
1201 static int vsock_dgram_recvmsg(struct socket *sock, struct msghdr *msg,
1202                                size_t len, int flags)
1203 {
1204         struct vsock_sock *vsk = vsock_sk(sock->sk);
1205
1206         return vsk->transport->dgram_dequeue(vsk, msg, len, flags);
1207 }
1208
1209 static const struct proto_ops vsock_dgram_ops = {
1210         .family = PF_VSOCK,
1211         .owner = THIS_MODULE,
1212         .release = vsock_release,
1213         .bind = vsock_bind,
1214         .connect = vsock_dgram_connect,
1215         .socketpair = sock_no_socketpair,
1216         .accept = sock_no_accept,
1217         .getname = vsock_getname,
1218         .poll = vsock_poll,
1219         .ioctl = sock_no_ioctl,
1220         .listen = sock_no_listen,
1221         .shutdown = vsock_shutdown,
1222         .sendmsg = vsock_dgram_sendmsg,
1223         .recvmsg = vsock_dgram_recvmsg,
1224         .mmap = sock_no_mmap,
1225         .sendpage = sock_no_sendpage,
1226 };
1227
1228 static int vsock_transport_cancel_pkt(struct vsock_sock *vsk)
1229 {
1230         const struct vsock_transport *transport = vsk->transport;
1231
1232         if (!transport->cancel_pkt)
1233                 return -EOPNOTSUPP;
1234
1235         return transport->cancel_pkt(vsk);
1236 }
1237
1238 static void vsock_connect_timeout(struct work_struct *work)
1239 {
1240         struct sock *sk;
1241         struct vsock_sock *vsk;
1242         int cancel = 0;
1243
1244         vsk = container_of(work, struct vsock_sock, connect_work.work);
1245         sk = sk_vsock(vsk);
1246
1247         lock_sock(sk);
1248         if (sk->sk_state == TCP_SYN_SENT &&
1249             (sk->sk_shutdown != SHUTDOWN_MASK)) {
1250                 sk->sk_state = TCP_CLOSE;
1251                 sk->sk_err = ETIMEDOUT;
1252                 sk->sk_error_report(sk);
1253                 cancel = 1;
1254         }
1255         release_sock(sk);
1256         if (cancel)
1257                 vsock_transport_cancel_pkt(vsk);
1258
1259         sock_put(sk);
1260 }
1261
1262 static int vsock_stream_connect(struct socket *sock, struct sockaddr *addr,
1263                                 int addr_len, int flags)
1264 {
1265         int err;
1266         struct sock *sk;
1267         struct vsock_sock *vsk;
1268         const struct vsock_transport *transport;
1269         struct sockaddr_vm *remote_addr;
1270         long timeout;
1271         DEFINE_WAIT(wait);
1272
1273         err = 0;
1274         sk = sock->sk;
1275         vsk = vsock_sk(sk);
1276
1277         lock_sock(sk);
1278
1279         /* XXX AF_UNSPEC should make us disconnect like AF_INET. */
1280         switch (sock->state) {
1281         case SS_CONNECTED:
1282                 err = -EISCONN;
1283                 goto out;
1284         case SS_DISCONNECTING:
1285                 err = -EINVAL;
1286                 goto out;
1287         case SS_CONNECTING:
1288                 /* This continues on so we can move sock into the SS_CONNECTED
1289                  * state once the connection has completed (at which point err
1290                  * will be set to zero also).  Otherwise, we will either wait
1291                  * for the connection or return -EALREADY should this be a
1292                  * non-blocking call.
1293                  */
1294                 err = -EALREADY;
1295                 break;
1296         default:
1297                 if ((sk->sk_state == TCP_LISTEN) ||
1298                     vsock_addr_cast(addr, addr_len, &remote_addr) != 0) {
1299                         err = -EINVAL;
1300                         goto out;
1301                 }
1302
1303                 /* Set the remote address that we are connecting to. */
1304                 memcpy(&vsk->remote_addr, remote_addr,
1305                        sizeof(vsk->remote_addr));
1306
1307                 err = vsock_assign_transport(vsk, NULL);
1308                 if (err)
1309                         goto out;
1310
1311                 transport = vsk->transport;
1312
1313                 /* The hypervisor and well-known contexts do not have socket
1314                  * endpoints.
1315                  */
1316                 if (!transport ||
1317                     !transport->stream_allow(remote_addr->svm_cid,
1318                                              remote_addr->svm_port)) {
1319                         err = -ENETUNREACH;
1320                         goto out;
1321                 }
1322
1323                 err = vsock_auto_bind(vsk);
1324                 if (err)
1325                         goto out;
1326
1327                 sk->sk_state = TCP_SYN_SENT;
1328
1329                 err = transport->connect(vsk);
1330                 if (err < 0)
1331                         goto out;
1332
1333                 /* Mark sock as connecting and set the error code to in
1334                  * progress in case this is a non-blocking connect.
1335                  */
1336                 sock->state = SS_CONNECTING;
1337                 err = -EINPROGRESS;
1338         }
1339
1340         /* The receive path will handle all communication until we are able to
1341          * enter the connected state.  Here we wait for the connection to be
1342          * completed or a notification of an error.
1343          */
1344         timeout = vsk->connect_timeout;
1345         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1346
1347         while (sk->sk_state != TCP_ESTABLISHED && sk->sk_err == 0) {
1348                 if (flags & O_NONBLOCK) {
1349                         /* If we're not going to block, we schedule a timeout
1350                          * function to generate a timeout on the connection
1351                          * attempt, in case the peer doesn't respond in a
1352                          * timely manner. We hold on to the socket until the
1353                          * timeout fires.
1354                          */
1355                         sock_hold(sk);
1356                         schedule_delayed_work(&vsk->connect_work, timeout);
1357
1358                         /* Skip ahead to preserve error code set above. */
1359                         goto out_wait;
1360                 }
1361
1362                 release_sock(sk);
1363                 timeout = schedule_timeout(timeout);
1364                 lock_sock(sk);
1365
1366                 if (signal_pending(current)) {
1367                         err = sock_intr_errno(timeout);
1368                         sk->sk_state = TCP_CLOSE;
1369                         sock->state = SS_UNCONNECTED;
1370                         vsock_transport_cancel_pkt(vsk);
1371                         goto out_wait;
1372                 } else if (timeout == 0) {
1373                         err = -ETIMEDOUT;
1374                         sk->sk_state = TCP_CLOSE;
1375                         sock->state = SS_UNCONNECTED;
1376                         vsock_transport_cancel_pkt(vsk);
1377                         goto out_wait;
1378                 }
1379
1380                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1381         }
1382
1383         if (sk->sk_err) {
1384                 err = -sk->sk_err;
1385                 sk->sk_state = TCP_CLOSE;
1386                 sock->state = SS_UNCONNECTED;
1387         } else {
1388                 err = 0;
1389         }
1390
1391 out_wait:
1392         finish_wait(sk_sleep(sk), &wait);
1393 out:
1394         release_sock(sk);
1395         return err;
1396 }
1397
1398 static int vsock_accept(struct socket *sock, struct socket *newsock, int flags,
1399                         bool kern)
1400 {
1401         struct sock *listener;
1402         int err;
1403         struct sock *connected;
1404         struct vsock_sock *vconnected;
1405         long timeout;
1406         DEFINE_WAIT(wait);
1407
1408         err = 0;
1409         listener = sock->sk;
1410
1411         lock_sock(listener);
1412
1413         if (sock->type != SOCK_STREAM) {
1414                 err = -EOPNOTSUPP;
1415                 goto out;
1416         }
1417
1418         if (listener->sk_state != TCP_LISTEN) {
1419                 err = -EINVAL;
1420                 goto out;
1421         }
1422
1423         /* Wait for children sockets to appear; these are the new sockets
1424          * created upon connection establishment.
1425          */
1426         timeout = sock_rcvtimeo(listener, flags & O_NONBLOCK);
1427         prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1428
1429         while ((connected = vsock_dequeue_accept(listener)) == NULL &&
1430                listener->sk_err == 0) {
1431                 release_sock(listener);
1432                 timeout = schedule_timeout(timeout);
1433                 finish_wait(sk_sleep(listener), &wait);
1434                 lock_sock(listener);
1435
1436                 if (signal_pending(current)) {
1437                         err = sock_intr_errno(timeout);
1438                         goto out;
1439                 } else if (timeout == 0) {
1440                         err = -EAGAIN;
1441                         goto out;
1442                 }
1443
1444                 prepare_to_wait(sk_sleep(listener), &wait, TASK_INTERRUPTIBLE);
1445         }
1446         finish_wait(sk_sleep(listener), &wait);
1447
1448         if (listener->sk_err)
1449                 err = -listener->sk_err;
1450
1451         if (connected) {
1452                 sk_acceptq_removed(listener);
1453
1454                 lock_sock_nested(connected, SINGLE_DEPTH_NESTING);
1455                 vconnected = vsock_sk(connected);
1456
1457                 /* If the listener socket has received an error, then we should
1458                  * reject this socket and return.  Note that we simply mark the
1459                  * socket rejected, drop our reference, and let the cleanup
1460                  * function handle the cleanup; the fact that we found it in
1461                  * the listener's accept queue guarantees that the cleanup
1462                  * function hasn't run yet.
1463                  */
1464                 if (err) {
1465                         vconnected->rejected = true;
1466                 } else {
1467                         newsock->state = SS_CONNECTED;
1468                         sock_graft(connected, newsock);
1469                 }
1470
1471                 release_sock(connected);
1472                 sock_put(connected);
1473         }
1474
1475 out:
1476         release_sock(listener);
1477         return err;
1478 }
1479
1480 static int vsock_listen(struct socket *sock, int backlog)
1481 {
1482         int err;
1483         struct sock *sk;
1484         struct vsock_sock *vsk;
1485
1486         sk = sock->sk;
1487
1488         lock_sock(sk);
1489
1490         if (sock->type != SOCK_STREAM) {
1491                 err = -EOPNOTSUPP;
1492                 goto out;
1493         }
1494
1495         if (sock->state != SS_UNCONNECTED) {
1496                 err = -EINVAL;
1497                 goto out;
1498         }
1499
1500         vsk = vsock_sk(sk);
1501
1502         if (!vsock_addr_bound(&vsk->local_addr)) {
1503                 err = -EINVAL;
1504                 goto out;
1505         }
1506
1507         sk->sk_max_ack_backlog = backlog;
1508         sk->sk_state = TCP_LISTEN;
1509
1510         err = 0;
1511
1512 out:
1513         release_sock(sk);
1514         return err;
1515 }
1516
1517 static void vsock_update_buffer_size(struct vsock_sock *vsk,
1518                                      const struct vsock_transport *transport,
1519                                      u64 val)
1520 {
1521         if (val > vsk->buffer_max_size)
1522                 val = vsk->buffer_max_size;
1523
1524         if (val < vsk->buffer_min_size)
1525                 val = vsk->buffer_min_size;
1526
1527         if (val != vsk->buffer_size &&
1528             transport && transport->notify_buffer_size)
1529                 transport->notify_buffer_size(vsk, &val);
1530
1531         vsk->buffer_size = val;
1532 }
1533
1534 static int vsock_stream_setsockopt(struct socket *sock,
1535                                    int level,
1536                                    int optname,
1537                                    sockptr_t optval,
1538                                    unsigned int optlen)
1539 {
1540         int err;
1541         struct sock *sk;
1542         struct vsock_sock *vsk;
1543         const struct vsock_transport *transport;
1544         u64 val;
1545
1546         if (level != AF_VSOCK)
1547                 return -ENOPROTOOPT;
1548
1549 #define COPY_IN(_v)                                       \
1550         do {                                              \
1551                 if (optlen < sizeof(_v)) {                \
1552                         err = -EINVAL;                    \
1553                         goto exit;                        \
1554                 }                                         \
1555                 if (copy_from_sockptr(&_v, optval, sizeof(_v)) != 0) {  \
1556                         err = -EFAULT;                                  \
1557                         goto exit;                                      \
1558                 }                                                       \
1559         } while (0)
1560
1561         err = 0;
1562         sk = sock->sk;
1563         vsk = vsock_sk(sk);
1564         transport = vsk->transport;
1565
1566         lock_sock(sk);
1567
1568         switch (optname) {
1569         case SO_VM_SOCKETS_BUFFER_SIZE:
1570                 COPY_IN(val);
1571                 vsock_update_buffer_size(vsk, transport, val);
1572                 break;
1573
1574         case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1575                 COPY_IN(val);
1576                 vsk->buffer_max_size = val;
1577                 vsock_update_buffer_size(vsk, transport, vsk->buffer_size);
1578                 break;
1579
1580         case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1581                 COPY_IN(val);
1582                 vsk->buffer_min_size = val;
1583                 vsock_update_buffer_size(vsk, transport, vsk->buffer_size);
1584                 break;
1585
1586         case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1587                 struct __kernel_old_timeval tv;
1588                 COPY_IN(tv);
1589                 if (tv.tv_sec >= 0 && tv.tv_usec < USEC_PER_SEC &&
1590                     tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) {
1591                         vsk->connect_timeout = tv.tv_sec * HZ +
1592                             DIV_ROUND_UP(tv.tv_usec, (1000000 / HZ));
1593                         if (vsk->connect_timeout == 0)
1594                                 vsk->connect_timeout =
1595                                     VSOCK_DEFAULT_CONNECT_TIMEOUT;
1596
1597                 } else {
1598                         err = -ERANGE;
1599                 }
1600                 break;
1601         }
1602
1603         default:
1604                 err = -ENOPROTOOPT;
1605                 break;
1606         }
1607
1608 #undef COPY_IN
1609
1610 exit:
1611         release_sock(sk);
1612         return err;
1613 }
1614
1615 static int vsock_stream_getsockopt(struct socket *sock,
1616                                    int level, int optname,
1617                                    char __user *optval,
1618                                    int __user *optlen)
1619 {
1620         int err;
1621         int len;
1622         struct sock *sk;
1623         struct vsock_sock *vsk;
1624         u64 val;
1625
1626         if (level != AF_VSOCK)
1627                 return -ENOPROTOOPT;
1628
1629         err = get_user(len, optlen);
1630         if (err != 0)
1631                 return err;
1632
1633 #define COPY_OUT(_v)                            \
1634         do {                                    \
1635                 if (len < sizeof(_v))           \
1636                         return -EINVAL;         \
1637                                                 \
1638                 len = sizeof(_v);               \
1639                 if (copy_to_user(optval, &_v, len) != 0)        \
1640                         return -EFAULT;                         \
1641                                                                 \
1642         } while (0)
1643
1644         err = 0;
1645         sk = sock->sk;
1646         vsk = vsock_sk(sk);
1647
1648         switch (optname) {
1649         case SO_VM_SOCKETS_BUFFER_SIZE:
1650                 val = vsk->buffer_size;
1651                 COPY_OUT(val);
1652                 break;
1653
1654         case SO_VM_SOCKETS_BUFFER_MAX_SIZE:
1655                 val = vsk->buffer_max_size;
1656                 COPY_OUT(val);
1657                 break;
1658
1659         case SO_VM_SOCKETS_BUFFER_MIN_SIZE:
1660                 val = vsk->buffer_min_size;
1661                 COPY_OUT(val);
1662                 break;
1663
1664         case SO_VM_SOCKETS_CONNECT_TIMEOUT: {
1665                 struct __kernel_old_timeval tv;
1666                 tv.tv_sec = vsk->connect_timeout / HZ;
1667                 tv.tv_usec =
1668                     (vsk->connect_timeout -
1669                      tv.tv_sec * HZ) * (1000000 / HZ);
1670                 COPY_OUT(tv);
1671                 break;
1672         }
1673         default:
1674                 return -ENOPROTOOPT;
1675         }
1676
1677         err = put_user(len, optlen);
1678         if (err != 0)
1679                 return -EFAULT;
1680
1681 #undef COPY_OUT
1682
1683         return 0;
1684 }
1685
1686 static int vsock_stream_sendmsg(struct socket *sock, struct msghdr *msg,
1687                                 size_t len)
1688 {
1689         struct sock *sk;
1690         struct vsock_sock *vsk;
1691         const struct vsock_transport *transport;
1692         ssize_t total_written;
1693         long timeout;
1694         int err;
1695         struct vsock_transport_send_notify_data send_data;
1696         DEFINE_WAIT_FUNC(wait, woken_wake_function);
1697
1698         sk = sock->sk;
1699         vsk = vsock_sk(sk);
1700         transport = vsk->transport;
1701         total_written = 0;
1702         err = 0;
1703
1704         if (msg->msg_flags & MSG_OOB)
1705                 return -EOPNOTSUPP;
1706
1707         lock_sock(sk);
1708
1709         /* Callers should not provide a destination with stream sockets. */
1710         if (msg->msg_namelen) {
1711                 err = sk->sk_state == TCP_ESTABLISHED ? -EISCONN : -EOPNOTSUPP;
1712                 goto out;
1713         }
1714
1715         /* Send data only if both sides are not shutdown in the direction. */
1716         if (sk->sk_shutdown & SEND_SHUTDOWN ||
1717             vsk->peer_shutdown & RCV_SHUTDOWN) {
1718                 err = -EPIPE;
1719                 goto out;
1720         }
1721
1722         if (!transport || sk->sk_state != TCP_ESTABLISHED ||
1723             !vsock_addr_bound(&vsk->local_addr)) {
1724                 err = -ENOTCONN;
1725                 goto out;
1726         }
1727
1728         if (!vsock_addr_bound(&vsk->remote_addr)) {
1729                 err = -EDESTADDRREQ;
1730                 goto out;
1731         }
1732
1733         /* Wait for room in the produce queue to enqueue our user's data. */
1734         timeout = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
1735
1736         err = transport->notify_send_init(vsk, &send_data);
1737         if (err < 0)
1738                 goto out;
1739
1740         while (total_written < len) {
1741                 ssize_t written;
1742
1743                 add_wait_queue(sk_sleep(sk), &wait);
1744                 while (vsock_stream_has_space(vsk) == 0 &&
1745                        sk->sk_err == 0 &&
1746                        !(sk->sk_shutdown & SEND_SHUTDOWN) &&
1747                        !(vsk->peer_shutdown & RCV_SHUTDOWN)) {
1748
1749                         /* Don't wait for non-blocking sockets. */
1750                         if (timeout == 0) {
1751                                 err = -EAGAIN;
1752                                 remove_wait_queue(sk_sleep(sk), &wait);
1753                                 goto out_err;
1754                         }
1755
1756                         err = transport->notify_send_pre_block(vsk, &send_data);
1757                         if (err < 0) {
1758                                 remove_wait_queue(sk_sleep(sk), &wait);
1759                                 goto out_err;
1760                         }
1761
1762                         release_sock(sk);
1763                         timeout = wait_woken(&wait, TASK_INTERRUPTIBLE, timeout);
1764                         lock_sock(sk);
1765                         if (signal_pending(current)) {
1766                                 err = sock_intr_errno(timeout);
1767                                 remove_wait_queue(sk_sleep(sk), &wait);
1768                                 goto out_err;
1769                         } else if (timeout == 0) {
1770                                 err = -EAGAIN;
1771                                 remove_wait_queue(sk_sleep(sk), &wait);
1772                                 goto out_err;
1773                         }
1774                 }
1775                 remove_wait_queue(sk_sleep(sk), &wait);
1776
1777                 /* These checks occur both as part of and after the loop
1778                  * conditional since we need to check before and after
1779                  * sleeping.
1780                  */
1781                 if (sk->sk_err) {
1782                         err = -sk->sk_err;
1783                         goto out_err;
1784                 } else if ((sk->sk_shutdown & SEND_SHUTDOWN) ||
1785                            (vsk->peer_shutdown & RCV_SHUTDOWN)) {
1786                         err = -EPIPE;
1787                         goto out_err;
1788                 }
1789
1790                 err = transport->notify_send_pre_enqueue(vsk, &send_data);
1791                 if (err < 0)
1792                         goto out_err;
1793
1794                 /* Note that enqueue will only write as many bytes as are free
1795                  * in the produce queue, so we don't need to ensure len is
1796                  * smaller than the queue size.  It is the caller's
1797                  * responsibility to check how many bytes we were able to send.
1798                  */
1799
1800                 written = transport->stream_enqueue(
1801                                 vsk, msg,
1802                                 len - total_written);
1803                 if (written < 0) {
1804                         err = -ENOMEM;
1805                         goto out_err;
1806                 }
1807
1808                 total_written += written;
1809
1810                 err = transport->notify_send_post_enqueue(
1811                                 vsk, written, &send_data);
1812                 if (err < 0)
1813                         goto out_err;
1814
1815         }
1816
1817 out_err:
1818         if (total_written > 0)
1819                 err = total_written;
1820 out:
1821         release_sock(sk);
1822         return err;
1823 }
1824
1825
1826 static int
1827 vsock_stream_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
1828                      int flags)
1829 {
1830         struct sock *sk;
1831         struct vsock_sock *vsk;
1832         const struct vsock_transport *transport;
1833         int err;
1834         size_t target;
1835         ssize_t copied;
1836         long timeout;
1837         struct vsock_transport_recv_notify_data recv_data;
1838
1839         DEFINE_WAIT(wait);
1840
1841         sk = sock->sk;
1842         vsk = vsock_sk(sk);
1843         transport = vsk->transport;
1844         err = 0;
1845
1846         lock_sock(sk);
1847
1848         if (!transport || sk->sk_state != TCP_ESTABLISHED) {
1849                 /* Recvmsg is supposed to return 0 if a peer performs an
1850                  * orderly shutdown. Differentiate between that case and when a
1851                  * peer has not connected or a local shutdown occured with the
1852                  * SOCK_DONE flag.
1853                  */
1854                 if (sock_flag(sk, SOCK_DONE))
1855                         err = 0;
1856                 else
1857                         err = -ENOTCONN;
1858
1859                 goto out;
1860         }
1861
1862         if (flags & MSG_OOB) {
1863                 err = -EOPNOTSUPP;
1864                 goto out;
1865         }
1866
1867         /* We don't check peer_shutdown flag here since peer may actually shut
1868          * down, but there can be data in the queue that a local socket can
1869          * receive.
1870          */
1871         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1872                 err = 0;
1873                 goto out;
1874         }
1875
1876         /* It is valid on Linux to pass in a zero-length receive buffer.  This
1877          * is not an error.  We may as well bail out now.
1878          */
1879         if (!len) {
1880                 err = 0;
1881                 goto out;
1882         }
1883
1884         /* We must not copy less than target bytes into the user's buffer
1885          * before returning successfully, so we wait for the consume queue to
1886          * have that much data to consume before dequeueing.  Note that this
1887          * makes it impossible to handle cases where target is greater than the
1888          * queue size.
1889          */
1890         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
1891         if (target >= transport->stream_rcvhiwat(vsk)) {
1892                 err = -ENOMEM;
1893                 goto out;
1894         }
1895         timeout = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1896         copied = 0;
1897
1898         err = transport->notify_recv_init(vsk, target, &recv_data);
1899         if (err < 0)
1900                 goto out;
1901
1902
1903         while (1) {
1904                 s64 ready;
1905
1906                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1907                 ready = vsock_stream_has_data(vsk);
1908
1909                 if (ready == 0) {
1910                         if (sk->sk_err != 0 ||
1911                             (sk->sk_shutdown & RCV_SHUTDOWN) ||
1912                             (vsk->peer_shutdown & SEND_SHUTDOWN)) {
1913                                 finish_wait(sk_sleep(sk), &wait);
1914                                 break;
1915                         }
1916                         /* Don't wait for non-blocking sockets. */
1917                         if (timeout == 0) {
1918                                 err = -EAGAIN;
1919                                 finish_wait(sk_sleep(sk), &wait);
1920                                 break;
1921                         }
1922
1923                         err = transport->notify_recv_pre_block(
1924                                         vsk, target, &recv_data);
1925                         if (err < 0) {
1926                                 finish_wait(sk_sleep(sk), &wait);
1927                                 break;
1928                         }
1929                         release_sock(sk);
1930                         timeout = schedule_timeout(timeout);
1931                         lock_sock(sk);
1932
1933                         if (signal_pending(current)) {
1934                                 err = sock_intr_errno(timeout);
1935                                 finish_wait(sk_sleep(sk), &wait);
1936                                 break;
1937                         } else if (timeout == 0) {
1938                                 err = -EAGAIN;
1939                                 finish_wait(sk_sleep(sk), &wait);
1940                                 break;
1941                         }
1942                 } else {
1943                         ssize_t read;
1944
1945                         finish_wait(sk_sleep(sk), &wait);
1946
1947                         if (ready < 0) {
1948                                 /* Invalid queue pair content. XXX This should
1949                                 * be changed to a connection reset in a later
1950                                 * change.
1951                                 */
1952
1953                                 err = -ENOMEM;
1954                                 goto out;
1955                         }
1956
1957                         err = transport->notify_recv_pre_dequeue(
1958                                         vsk, target, &recv_data);
1959                         if (err < 0)
1960                                 break;
1961
1962                         read = transport->stream_dequeue(
1963                                         vsk, msg,
1964                                         len - copied, flags);
1965                         if (read < 0) {
1966                                 err = -ENOMEM;
1967                                 break;
1968                         }
1969
1970                         copied += read;
1971
1972                         err = transport->notify_recv_post_dequeue(
1973                                         vsk, target, read,
1974                                         !(flags & MSG_PEEK), &recv_data);
1975                         if (err < 0)
1976                                 goto out;
1977
1978                         if (read >= target || flags & MSG_PEEK)
1979                                 break;
1980
1981                         target -= read;
1982                 }
1983         }
1984
1985         if (sk->sk_err)
1986                 err = -sk->sk_err;
1987         else if (sk->sk_shutdown & RCV_SHUTDOWN)
1988                 err = 0;
1989
1990         if (copied > 0)
1991                 err = copied;
1992
1993 out:
1994         release_sock(sk);
1995         return err;
1996 }
1997
1998 static const struct proto_ops vsock_stream_ops = {
1999         .family = PF_VSOCK,
2000         .owner = THIS_MODULE,
2001         .release = vsock_release,
2002         .bind = vsock_bind,
2003         .connect = vsock_stream_connect,
2004         .socketpair = sock_no_socketpair,
2005         .accept = vsock_accept,
2006         .getname = vsock_getname,
2007         .poll = vsock_poll,
2008         .ioctl = sock_no_ioctl,
2009         .listen = vsock_listen,
2010         .shutdown = vsock_shutdown,
2011         .setsockopt = vsock_stream_setsockopt,
2012         .getsockopt = vsock_stream_getsockopt,
2013         .sendmsg = vsock_stream_sendmsg,
2014         .recvmsg = vsock_stream_recvmsg,
2015         .mmap = sock_no_mmap,
2016         .sendpage = sock_no_sendpage,
2017 };
2018
2019 static int vsock_create(struct net *net, struct socket *sock,
2020                         int protocol, int kern)
2021 {
2022         struct vsock_sock *vsk;
2023         struct sock *sk;
2024         int ret;
2025
2026         if (!sock)
2027                 return -EINVAL;
2028
2029         if (protocol && protocol != PF_VSOCK)
2030                 return -EPROTONOSUPPORT;
2031
2032         switch (sock->type) {
2033         case SOCK_DGRAM:
2034                 sock->ops = &vsock_dgram_ops;
2035                 break;
2036         case SOCK_STREAM:
2037                 sock->ops = &vsock_stream_ops;
2038                 break;
2039         default:
2040                 return -ESOCKTNOSUPPORT;
2041         }
2042
2043         sock->state = SS_UNCONNECTED;
2044
2045         sk = __vsock_create(net, sock, NULL, GFP_KERNEL, 0, kern);
2046         if (!sk)
2047                 return -ENOMEM;
2048
2049         vsk = vsock_sk(sk);
2050
2051         if (sock->type == SOCK_DGRAM) {
2052                 ret = vsock_assign_transport(vsk, NULL);
2053                 if (ret < 0) {
2054                         sock_put(sk);
2055                         return ret;
2056                 }
2057         }
2058
2059         vsock_insert_unbound(vsk);
2060
2061         return 0;
2062 }
2063
2064 static const struct net_proto_family vsock_family_ops = {
2065         .family = AF_VSOCK,
2066         .create = vsock_create,
2067         .owner = THIS_MODULE,
2068 };
2069
2070 static long vsock_dev_do_ioctl(struct file *filp,
2071                                unsigned int cmd, void __user *ptr)
2072 {
2073         u32 __user *p = ptr;
2074         u32 cid = VMADDR_CID_ANY;
2075         int retval = 0;
2076
2077         switch (cmd) {
2078         case IOCTL_VM_SOCKETS_GET_LOCAL_CID:
2079                 /* To be compatible with the VMCI behavior, we prioritize the
2080                  * guest CID instead of well-know host CID (VMADDR_CID_HOST).
2081                  */
2082                 if (transport_g2h)
2083                         cid = transport_g2h->get_local_cid();
2084                 else if (transport_h2g)
2085                         cid = transport_h2g->get_local_cid();
2086
2087                 if (put_user(cid, p) != 0)
2088                         retval = -EFAULT;
2089                 break;
2090
2091         default:
2092                 retval = -ENOIOCTLCMD;
2093         }
2094
2095         return retval;
2096 }
2097
2098 static long vsock_dev_ioctl(struct file *filp,
2099                             unsigned int cmd, unsigned long arg)
2100 {
2101         return vsock_dev_do_ioctl(filp, cmd, (void __user *)arg);
2102 }
2103
2104 #ifdef CONFIG_COMPAT
2105 static long vsock_dev_compat_ioctl(struct file *filp,
2106                                    unsigned int cmd, unsigned long arg)
2107 {
2108         return vsock_dev_do_ioctl(filp, cmd, compat_ptr(arg));
2109 }
2110 #endif
2111
2112 static const struct file_operations vsock_device_ops = {
2113         .owner          = THIS_MODULE,
2114         .unlocked_ioctl = vsock_dev_ioctl,
2115 #ifdef CONFIG_COMPAT
2116         .compat_ioctl   = vsock_dev_compat_ioctl,
2117 #endif
2118         .open           = nonseekable_open,
2119 };
2120
2121 static struct miscdevice vsock_device = {
2122         .name           = "vsock",
2123         .fops           = &vsock_device_ops,
2124 };
2125
2126 static int __init vsock_init(void)
2127 {
2128         int err = 0;
2129
2130         vsock_init_tables();
2131
2132         vsock_proto.owner = THIS_MODULE;
2133         vsock_device.minor = MISC_DYNAMIC_MINOR;
2134         err = misc_register(&vsock_device);
2135         if (err) {
2136                 pr_err("Failed to register misc device\n");
2137                 goto err_reset_transport;
2138         }
2139
2140         err = proto_register(&vsock_proto, 1);  /* we want our slab */
2141         if (err) {
2142                 pr_err("Cannot register vsock protocol\n");
2143                 goto err_deregister_misc;
2144         }
2145
2146         err = sock_register(&vsock_family_ops);
2147         if (err) {
2148                 pr_err("could not register af_vsock (%d) address family: %d\n",
2149                        AF_VSOCK, err);
2150                 goto err_unregister_proto;
2151         }
2152
2153         return 0;
2154
2155 err_unregister_proto:
2156         proto_unregister(&vsock_proto);
2157 err_deregister_misc:
2158         misc_deregister(&vsock_device);
2159 err_reset_transport:
2160         return err;
2161 }
2162
2163 static void __exit vsock_exit(void)
2164 {
2165         misc_deregister(&vsock_device);
2166         sock_unregister(AF_VSOCK);
2167         proto_unregister(&vsock_proto);
2168 }
2169
2170 const struct vsock_transport *vsock_core_get_transport(struct vsock_sock *vsk)
2171 {
2172         return vsk->transport;
2173 }
2174 EXPORT_SYMBOL_GPL(vsock_core_get_transport);
2175
2176 int vsock_core_register(const struct vsock_transport *t, int features)
2177 {
2178         const struct vsock_transport *t_h2g, *t_g2h, *t_dgram, *t_local;
2179         int err = mutex_lock_interruptible(&vsock_register_mutex);
2180
2181         if (err)
2182                 return err;
2183
2184         t_h2g = transport_h2g;
2185         t_g2h = transport_g2h;
2186         t_dgram = transport_dgram;
2187         t_local = transport_local;
2188
2189         if (features & VSOCK_TRANSPORT_F_H2G) {
2190                 if (t_h2g) {
2191                         err = -EBUSY;
2192                         goto err_busy;
2193                 }
2194                 t_h2g = t;
2195         }
2196
2197         if (features & VSOCK_TRANSPORT_F_G2H) {
2198                 if (t_g2h) {
2199                         err = -EBUSY;
2200                         goto err_busy;
2201                 }
2202                 t_g2h = t;
2203         }
2204
2205         if (features & VSOCK_TRANSPORT_F_DGRAM) {
2206                 if (t_dgram) {
2207                         err = -EBUSY;
2208                         goto err_busy;
2209                 }
2210                 t_dgram = t;
2211         }
2212
2213         if (features & VSOCK_TRANSPORT_F_LOCAL) {
2214                 if (t_local) {
2215                         err = -EBUSY;
2216                         goto err_busy;
2217                 }
2218                 t_local = t;
2219         }
2220
2221         transport_h2g = t_h2g;
2222         transport_g2h = t_g2h;
2223         transport_dgram = t_dgram;
2224         transport_local = t_local;
2225
2226 err_busy:
2227         mutex_unlock(&vsock_register_mutex);
2228         return err;
2229 }
2230 EXPORT_SYMBOL_GPL(vsock_core_register);
2231
2232 void vsock_core_unregister(const struct vsock_transport *t)
2233 {
2234         mutex_lock(&vsock_register_mutex);
2235
2236         if (transport_h2g == t)
2237                 transport_h2g = NULL;
2238
2239         if (transport_g2h == t)
2240                 transport_g2h = NULL;
2241
2242         if (transport_dgram == t)
2243                 transport_dgram = NULL;
2244
2245         if (transport_local == t)
2246                 transport_local = NULL;
2247
2248         mutex_unlock(&vsock_register_mutex);
2249 }
2250 EXPORT_SYMBOL_GPL(vsock_core_unregister);
2251
2252 module_init(vsock_init);
2253 module_exit(vsock_exit);
2254
2255 MODULE_AUTHOR("VMware, Inc.");
2256 MODULE_DESCRIPTION("VMware Virtual Socket Family");
2257 MODULE_VERSION("1.0.2.0-k");
2258 MODULE_LICENSE("GPL v2");