1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * INET An implementation of the TCP/IP protocol suite for the LINUX 4 * operating system. INET is implemented using the BSD Socket 5 * interface as the means of communication with the user level. 6 * 7 * Generic socket support routines. Memory allocators, socket lock/release 8 * handler for protocols to use and generic option handler. 9 * 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Florian La Roche, <flla@stud.uni-sb.de> 13 * Alan Cox, <A.Cox@swansea.ac.uk> 14 * 15 * Fixes: 16 * Alan Cox : Numerous verify_area() problems 17 * Alan Cox : Connecting on a connecting socket 18 * now returns an error for tcp. 19 * Alan Cox : sock->protocol is set correctly. 20 * and is not sometimes left as 0. 21 * Alan Cox : connect handles icmp errors on a 22 * connect properly. Unfortunately there 23 * is a restart syscall nasty there. I 24 * can't match BSD without hacking the C 25 * library. Ideas urgently sought! 26 * Alan Cox : Disallow bind() to addresses that are 27 * not ours - especially broadcast ones!! 28 * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost) 29 * Alan Cox : sock_wfree/sock_rfree don't destroy sockets, 30 * instead they leave that for the DESTROY timer. 31 * Alan Cox : Clean up error flag in accept 32 * Alan Cox : TCP ack handling is buggy, the DESTROY timer 33 * was buggy. Put a remove_sock() in the handler 34 * for memory when we hit 0. Also altered the timer 35 * code. The ACK stuff can wait and needs major 36 * TCP layer surgery. 37 * Alan Cox : Fixed TCP ack bug, removed remove sock 38 * and fixed timer/inet_bh race. 39 * Alan Cox : Added zapped flag for TCP 40 * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code 41 * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb 42 * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources 43 * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing. 44 * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so... 45 * Rick Sladkey : Relaxed UDP rules for matching packets. 46 * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support 47 * Pauline Middelink : identd support 48 * Alan Cox : Fixed connect() taking signals I think. 49 * Alan Cox : SO_LINGER supported 50 * Alan Cox : Error reporting fixes 51 * Anonymous : inet_create tidied up (sk->reuse setting) 52 * Alan Cox : inet sockets don't set sk->type! 53 * Alan Cox : Split socket option code 54 * Alan Cox : Callbacks 55 * Alan Cox : Nagle flag for Charles & Johannes stuff 56 * Alex : Removed restriction on inet fioctl 57 * Alan Cox : Splitting INET from NET core 58 * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt() 59 * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code 60 * Alan Cox : Split IP from generic code 61 * Alan Cox : New kfree_skbmem() 62 * Alan Cox : Make SO_DEBUG superuser only. 63 * Alan Cox : Allow anyone to clear SO_DEBUG 64 * (compatibility fix) 65 * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput. 66 * Alan Cox : Allocator for a socket is settable. 67 * Alan Cox : SO_ERROR includes soft errors. 68 * Alan Cox : Allow NULL arguments on some SO_ opts 69 * Alan Cox : Generic socket allocation to make hooks 70 * easier (suggested by Craig Metz). 71 * Michael Pall : SO_ERROR returns positive errno again 72 * Steve Whitehouse: Added default destructor to free 73 * protocol private data. 74 * Steve Whitehouse: Added various other default routines 75 * common to several socket families. 76 * Chris Evans : Call suser() check last on F_SETOWN 77 * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER. 78 * Andi Kleen : Add sock_kmalloc()/sock_kfree_s() 79 * Andi Kleen : Fix write_space callback 80 * Chris Evans : Security fixes - signedness again 81 * Arnaldo C. Melo : cleanups, use skb_queue_purge 82 * 83 * To Fix: 84 */ 85 86 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 87 88 #include <asm/unaligned.h> 89 #include <linux/capability.h> 90 #include <linux/errno.h> 91 #include <linux/errqueue.h> 92 #include <linux/types.h> 93 #include <linux/socket.h> 94 #include <linux/in.h> 95 #include <linux/kernel.h> 96 #include <linux/module.h> 97 #include <linux/proc_fs.h> 98 #include <linux/seq_file.h> 99 #include <linux/sched.h> 100 #include <linux/sched/mm.h> 101 #include <linux/timer.h> 102 #include <linux/string.h> 103 #include <linux/sockios.h> 104 #include <linux/net.h> 105 #include <linux/mm.h> 106 #include <linux/slab.h> 107 #include <linux/interrupt.h> 108 #include <linux/poll.h> 109 #include <linux/tcp.h> 110 #include <linux/init.h> 111 #include <linux/highmem.h> 112 #include <linux/user_namespace.h> 113 #include <linux/static_key.h> 114 #include <linux/memcontrol.h> 115 #include <linux/prefetch.h> 116 117 #include <linux/uaccess.h> 118 119 #include <linux/netdevice.h> 120 #include <net/protocol.h> 121 #include <linux/skbuff.h> 122 #include <net/net_namespace.h> 123 #include <net/request_sock.h> 124 #include <net/sock.h> 125 #include <linux/net_tstamp.h> 126 #include <net/xfrm.h> 127 #include <linux/ipsec.h> 128 #include <net/cls_cgroup.h> 129 #include <net/netprio_cgroup.h> 130 #include <linux/sock_diag.h> 131 132 #include <linux/filter.h> 133 #include <net/sock_reuseport.h> 134 #include <net/bpf_sk_storage.h> 135 136 #include <trace/events/sock.h> 137 138 #include <net/tcp.h> 139 #include <net/busy_poll.h> 140 141 static DEFINE_MUTEX(proto_list_mutex); 142 static LIST_HEAD(proto_list); 143 144 static void sock_inuse_add(struct net *net, int val); 145 146 /** 147 * sk_ns_capable - General socket capability test 148 * @sk: Socket to use a capability on or through 149 * @user_ns: The user namespace of the capability to use 150 * @cap: The capability to use 151 * 152 * Test to see if the opener of the socket had when the socket was 153 * created and the current process has the capability @cap in the user 154 * namespace @user_ns. 155 */ 156 bool sk_ns_capable(const struct sock *sk, 157 struct user_namespace *user_ns, int cap) 158 { 159 return file_ns_capable(sk->sk_socket->file, user_ns, cap) && 160 ns_capable(user_ns, cap); 161 } 162 EXPORT_SYMBOL(sk_ns_capable); 163 164 /** 165 * sk_capable - Socket global capability test 166 * @sk: Socket to use a capability on or through 167 * @cap: The global capability to use 168 * 169 * Test to see if the opener of the socket had when the socket was 170 * created and the current process has the capability @cap in all user 171 * namespaces. 172 */ 173 bool sk_capable(const struct sock *sk, int cap) 174 { 175 return sk_ns_capable(sk, &init_user_ns, cap); 176 } 177 EXPORT_SYMBOL(sk_capable); 178 179 /** 180 * sk_net_capable - Network namespace socket capability test 181 * @sk: Socket to use a capability on or through 182 * @cap: The capability to use 183 * 184 * Test to see if the opener of the socket had when the socket was created 185 * and the current process has the capability @cap over the network namespace 186 * the socket is a member of. 187 */ 188 bool sk_net_capable(const struct sock *sk, int cap) 189 { 190 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap); 191 } 192 EXPORT_SYMBOL(sk_net_capable); 193 194 /* 195 * Each address family might have different locking rules, so we have 196 * one slock key per address family and separate keys for internal and 197 * userspace sockets. 198 */ 199 static struct lock_class_key af_family_keys[AF_MAX]; 200 static struct lock_class_key af_family_kern_keys[AF_MAX]; 201 static struct lock_class_key af_family_slock_keys[AF_MAX]; 202 static struct lock_class_key af_family_kern_slock_keys[AF_MAX]; 203 204 /* 205 * Make lock validator output more readable. (we pre-construct these 206 * strings build-time, so that runtime initialization of socket 207 * locks is fast): 208 */ 209 210 #define _sock_locks(x) \ 211 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \ 212 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \ 213 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \ 214 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \ 215 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \ 216 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \ 217 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \ 218 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \ 219 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \ 220 x "27" , x "28" , x "AF_CAN" , \ 221 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \ 222 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \ 223 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \ 224 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \ 225 x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \ 226 x "AF_MAX" 227 228 static const char *const af_family_key_strings[AF_MAX+1] = { 229 _sock_locks("sk_lock-") 230 }; 231 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 232 _sock_locks("slock-") 233 }; 234 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 235 _sock_locks("clock-") 236 }; 237 238 static const char *const af_family_kern_key_strings[AF_MAX+1] = { 239 _sock_locks("k-sk_lock-") 240 }; 241 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = { 242 _sock_locks("k-slock-") 243 }; 244 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = { 245 _sock_locks("k-clock-") 246 }; 247 static const char *const af_family_rlock_key_strings[AF_MAX+1] = { 248 _sock_locks("rlock-") 249 }; 250 static const char *const af_family_wlock_key_strings[AF_MAX+1] = { 251 _sock_locks("wlock-") 252 }; 253 static const char *const af_family_elock_key_strings[AF_MAX+1] = { 254 _sock_locks("elock-") 255 }; 256 257 /* 258 * sk_callback_lock and sk queues locking rules are per-address-family, 259 * so split the lock classes by using a per-AF key: 260 */ 261 static struct lock_class_key af_callback_keys[AF_MAX]; 262 static struct lock_class_key af_rlock_keys[AF_MAX]; 263 static struct lock_class_key af_wlock_keys[AF_MAX]; 264 static struct lock_class_key af_elock_keys[AF_MAX]; 265 static struct lock_class_key af_kern_callback_keys[AF_MAX]; 266 267 /* Run time adjustable parameters. */ 268 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 269 EXPORT_SYMBOL(sysctl_wmem_max); 270 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 271 EXPORT_SYMBOL(sysctl_rmem_max); 272 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 273 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 274 275 /* Maximal space eaten by iovec or ancillary data plus some space */ 276 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); 277 EXPORT_SYMBOL(sysctl_optmem_max); 278 279 int sysctl_tstamp_allow_data __read_mostly = 1; 280 281 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key); 282 EXPORT_SYMBOL_GPL(memalloc_socks_key); 283 284 /** 285 * sk_set_memalloc - sets %SOCK_MEMALLOC 286 * @sk: socket to set it on 287 * 288 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 289 * It's the responsibility of the admin to adjust min_free_kbytes 290 * to meet the requirements 291 */ 292 void sk_set_memalloc(struct sock *sk) 293 { 294 sock_set_flag(sk, SOCK_MEMALLOC); 295 sk->sk_allocation |= __GFP_MEMALLOC; 296 static_branch_inc(&memalloc_socks_key); 297 } 298 EXPORT_SYMBOL_GPL(sk_set_memalloc); 299 300 void sk_clear_memalloc(struct sock *sk) 301 { 302 sock_reset_flag(sk, SOCK_MEMALLOC); 303 sk->sk_allocation &= ~__GFP_MEMALLOC; 304 static_branch_dec(&memalloc_socks_key); 305 306 /* 307 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 308 * progress of swapping. SOCK_MEMALLOC may be cleared while 309 * it has rmem allocations due to the last swapfile being deactivated 310 * but there is a risk that the socket is unusable due to exceeding 311 * the rmem limits. Reclaim the reserves and obey rmem limits again. 312 */ 313 sk_mem_reclaim(sk); 314 } 315 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 316 317 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 318 { 319 int ret; 320 unsigned int noreclaim_flag; 321 322 /* these should have been dropped before queueing */ 323 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 324 325 noreclaim_flag = memalloc_noreclaim_save(); 326 ret = sk->sk_backlog_rcv(sk, skb); 327 memalloc_noreclaim_restore(noreclaim_flag); 328 329 return ret; 330 } 331 EXPORT_SYMBOL(__sk_backlog_rcv); 332 333 static int sock_get_timeout(long timeo, void *optval, bool old_timeval) 334 { 335 struct __kernel_sock_timeval tv; 336 int size; 337 338 if (timeo == MAX_SCHEDULE_TIMEOUT) { 339 tv.tv_sec = 0; 340 tv.tv_usec = 0; 341 } else { 342 tv.tv_sec = timeo / HZ; 343 tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ; 344 } 345 346 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) { 347 struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec }; 348 *(struct old_timeval32 *)optval = tv32; 349 return sizeof(tv32); 350 } 351 352 if (old_timeval) { 353 struct __kernel_old_timeval old_tv; 354 old_tv.tv_sec = tv.tv_sec; 355 old_tv.tv_usec = tv.tv_usec; 356 *(struct __kernel_old_timeval *)optval = old_tv; 357 size = sizeof(old_tv); 358 } else { 359 *(struct __kernel_sock_timeval *)optval = tv; 360 size = sizeof(tv); 361 } 362 363 return size; 364 } 365 366 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen, bool old_timeval) 367 { 368 struct __kernel_sock_timeval tv; 369 370 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) { 371 struct old_timeval32 tv32; 372 373 if (optlen < sizeof(tv32)) 374 return -EINVAL; 375 376 if (copy_from_user(&tv32, optval, sizeof(tv32))) 377 return -EFAULT; 378 tv.tv_sec = tv32.tv_sec; 379 tv.tv_usec = tv32.tv_usec; 380 } else if (old_timeval) { 381 struct __kernel_old_timeval old_tv; 382 383 if (optlen < sizeof(old_tv)) 384 return -EINVAL; 385 if (copy_from_user(&old_tv, optval, sizeof(old_tv))) 386 return -EFAULT; 387 tv.tv_sec = old_tv.tv_sec; 388 tv.tv_usec = old_tv.tv_usec; 389 } else { 390 if (optlen < sizeof(tv)) 391 return -EINVAL; 392 if (copy_from_user(&tv, optval, sizeof(tv))) 393 return -EFAULT; 394 } 395 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 396 return -EDOM; 397 398 if (tv.tv_sec < 0) { 399 static int warned __read_mostly; 400 401 *timeo_p = 0; 402 if (warned < 10 && net_ratelimit()) { 403 warned++; 404 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 405 __func__, current->comm, task_pid_nr(current)); 406 } 407 return 0; 408 } 409 *timeo_p = MAX_SCHEDULE_TIMEOUT; 410 if (tv.tv_sec == 0 && tv.tv_usec == 0) 411 return 0; 412 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) 413 *timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ); 414 return 0; 415 } 416 417 static void sock_warn_obsolete_bsdism(const char *name) 418 { 419 static int warned; 420 static char warncomm[TASK_COMM_LEN]; 421 if (strcmp(warncomm, current->comm) && warned < 5) { 422 strcpy(warncomm, current->comm); 423 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", 424 warncomm, name); 425 warned++; 426 } 427 } 428 429 static bool sock_needs_netstamp(const struct sock *sk) 430 { 431 switch (sk->sk_family) { 432 case AF_UNSPEC: 433 case AF_UNIX: 434 return false; 435 default: 436 return true; 437 } 438 } 439 440 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 441 { 442 if (sk->sk_flags & flags) { 443 sk->sk_flags &= ~flags; 444 if (sock_needs_netstamp(sk) && 445 !(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 446 net_disable_timestamp(); 447 } 448 } 449 450 451 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 452 { 453 unsigned long flags; 454 struct sk_buff_head *list = &sk->sk_receive_queue; 455 456 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 457 atomic_inc(&sk->sk_drops); 458 trace_sock_rcvqueue_full(sk, skb); 459 return -ENOMEM; 460 } 461 462 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 463 atomic_inc(&sk->sk_drops); 464 return -ENOBUFS; 465 } 466 467 skb->dev = NULL; 468 skb_set_owner_r(skb, sk); 469 470 /* we escape from rcu protected region, make sure we dont leak 471 * a norefcounted dst 472 */ 473 skb_dst_force(skb); 474 475 spin_lock_irqsave(&list->lock, flags); 476 sock_skb_set_dropcount(sk, skb); 477 __skb_queue_tail(list, skb); 478 spin_unlock_irqrestore(&list->lock, flags); 479 480 if (!sock_flag(sk, SOCK_DEAD)) 481 sk->sk_data_ready(sk); 482 return 0; 483 } 484 EXPORT_SYMBOL(__sock_queue_rcv_skb); 485 486 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 487 { 488 int err; 489 490 err = sk_filter(sk, skb); 491 if (err) 492 return err; 493 494 return __sock_queue_rcv_skb(sk, skb); 495 } 496 EXPORT_SYMBOL(sock_queue_rcv_skb); 497 498 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, 499 const int nested, unsigned int trim_cap, bool refcounted) 500 { 501 int rc = NET_RX_SUCCESS; 502 503 if (sk_filter_trim_cap(sk, skb, trim_cap)) 504 goto discard_and_relse; 505 506 skb->dev = NULL; 507 508 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 509 atomic_inc(&sk->sk_drops); 510 goto discard_and_relse; 511 } 512 if (nested) 513 bh_lock_sock_nested(sk); 514 else 515 bh_lock_sock(sk); 516 if (!sock_owned_by_user(sk)) { 517 /* 518 * trylock + unlock semantics: 519 */ 520 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 521 522 rc = sk_backlog_rcv(sk, skb); 523 524 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 525 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 526 bh_unlock_sock(sk); 527 atomic_inc(&sk->sk_drops); 528 goto discard_and_relse; 529 } 530 531 bh_unlock_sock(sk); 532 out: 533 if (refcounted) 534 sock_put(sk); 535 return rc; 536 discard_and_relse: 537 kfree_skb(skb); 538 goto out; 539 } 540 EXPORT_SYMBOL(__sk_receive_skb); 541 542 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 543 { 544 struct dst_entry *dst = __sk_dst_get(sk); 545 546 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 547 sk_tx_queue_clear(sk); 548 sk->sk_dst_pending_confirm = 0; 549 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 550 dst_release(dst); 551 return NULL; 552 } 553 554 return dst; 555 } 556 EXPORT_SYMBOL(__sk_dst_check); 557 558 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 559 { 560 struct dst_entry *dst = sk_dst_get(sk); 561 562 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 563 sk_dst_reset(sk); 564 dst_release(dst); 565 return NULL; 566 } 567 568 return dst; 569 } 570 EXPORT_SYMBOL(sk_dst_check); 571 572 static int sock_setbindtodevice_locked(struct sock *sk, int ifindex) 573 { 574 int ret = -ENOPROTOOPT; 575 #ifdef CONFIG_NETDEVICES 576 struct net *net = sock_net(sk); 577 578 /* Sorry... */ 579 ret = -EPERM; 580 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 581 goto out; 582 583 ret = -EINVAL; 584 if (ifindex < 0) 585 goto out; 586 587 sk->sk_bound_dev_if = ifindex; 588 if (sk->sk_prot->rehash) 589 sk->sk_prot->rehash(sk); 590 sk_dst_reset(sk); 591 592 ret = 0; 593 594 out: 595 #endif 596 597 return ret; 598 } 599 600 static int sock_setbindtodevice(struct sock *sk, char __user *optval, 601 int optlen) 602 { 603 int ret = -ENOPROTOOPT; 604 #ifdef CONFIG_NETDEVICES 605 struct net *net = sock_net(sk); 606 char devname[IFNAMSIZ]; 607 int index; 608 609 ret = -EINVAL; 610 if (optlen < 0) 611 goto out; 612 613 /* Bind this socket to a particular device like "eth0", 614 * as specified in the passed interface name. If the 615 * name is "" or the option length is zero the socket 616 * is not bound. 617 */ 618 if (optlen > IFNAMSIZ - 1) 619 optlen = IFNAMSIZ - 1; 620 memset(devname, 0, sizeof(devname)); 621 622 ret = -EFAULT; 623 if (copy_from_user(devname, optval, optlen)) 624 goto out; 625 626 index = 0; 627 if (devname[0] != '\0') { 628 struct net_device *dev; 629 630 rcu_read_lock(); 631 dev = dev_get_by_name_rcu(net, devname); 632 if (dev) 633 index = dev->ifindex; 634 rcu_read_unlock(); 635 ret = -ENODEV; 636 if (!dev) 637 goto out; 638 } 639 640 lock_sock(sk); 641 ret = sock_setbindtodevice_locked(sk, index); 642 release_sock(sk); 643 644 out: 645 #endif 646 647 return ret; 648 } 649 650 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 651 int __user *optlen, int len) 652 { 653 int ret = -ENOPROTOOPT; 654 #ifdef CONFIG_NETDEVICES 655 struct net *net = sock_net(sk); 656 char devname[IFNAMSIZ]; 657 658 if (sk->sk_bound_dev_if == 0) { 659 len = 0; 660 goto zero; 661 } 662 663 ret = -EINVAL; 664 if (len < IFNAMSIZ) 665 goto out; 666 667 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); 668 if (ret) 669 goto out; 670 671 len = strlen(devname) + 1; 672 673 ret = -EFAULT; 674 if (copy_to_user(optval, devname, len)) 675 goto out; 676 677 zero: 678 ret = -EFAULT; 679 if (put_user(len, optlen)) 680 goto out; 681 682 ret = 0; 683 684 out: 685 #endif 686 687 return ret; 688 } 689 690 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit, 691 int valbool) 692 { 693 if (valbool) 694 sock_set_flag(sk, bit); 695 else 696 sock_reset_flag(sk, bit); 697 } 698 699 bool sk_mc_loop(struct sock *sk) 700 { 701 if (dev_recursion_level()) 702 return false; 703 if (!sk) 704 return true; 705 switch (sk->sk_family) { 706 case AF_INET: 707 return inet_sk(sk)->mc_loop; 708 #if IS_ENABLED(CONFIG_IPV6) 709 case AF_INET6: 710 return inet6_sk(sk)->mc_loop; 711 #endif 712 } 713 WARN_ON(1); 714 return true; 715 } 716 EXPORT_SYMBOL(sk_mc_loop); 717 718 /* 719 * This is meant for all protocols to use and covers goings on 720 * at the socket level. Everything here is generic. 721 */ 722 723 int sock_setsockopt(struct socket *sock, int level, int optname, 724 char __user *optval, unsigned int optlen) 725 { 726 struct sock_txtime sk_txtime; 727 struct sock *sk = sock->sk; 728 int val; 729 int valbool; 730 struct linger ling; 731 int ret = 0; 732 733 /* 734 * Options without arguments 735 */ 736 737 if (optname == SO_BINDTODEVICE) 738 return sock_setbindtodevice(sk, optval, optlen); 739 740 if (optlen < sizeof(int)) 741 return -EINVAL; 742 743 if (get_user(val, (int __user *)optval)) 744 return -EFAULT; 745 746 valbool = val ? 1 : 0; 747 748 lock_sock(sk); 749 750 switch (optname) { 751 case SO_DEBUG: 752 if (val && !capable(CAP_NET_ADMIN)) 753 ret = -EACCES; 754 else 755 sock_valbool_flag(sk, SOCK_DBG, valbool); 756 break; 757 case SO_REUSEADDR: 758 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 759 break; 760 case SO_REUSEPORT: 761 sk->sk_reuseport = valbool; 762 break; 763 case SO_TYPE: 764 case SO_PROTOCOL: 765 case SO_DOMAIN: 766 case SO_ERROR: 767 ret = -ENOPROTOOPT; 768 break; 769 case SO_DONTROUTE: 770 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 771 sk_dst_reset(sk); 772 break; 773 case SO_BROADCAST: 774 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 775 break; 776 case SO_SNDBUF: 777 /* Don't error on this BSD doesn't and if you think 778 * about it this is right. Otherwise apps have to 779 * play 'guess the biggest size' games. RCVBUF/SNDBUF 780 * are treated in BSD as hints 781 */ 782 val = min_t(u32, val, sysctl_wmem_max); 783 set_sndbuf: 784 /* Ensure val * 2 fits into an int, to prevent max_t() 785 * from treating it as a negative value. 786 */ 787 val = min_t(int, val, INT_MAX / 2); 788 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 789 sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF); 790 /* Wake up sending tasks if we upped the value. */ 791 sk->sk_write_space(sk); 792 break; 793 794 case SO_SNDBUFFORCE: 795 if (!capable(CAP_NET_ADMIN)) { 796 ret = -EPERM; 797 break; 798 } 799 800 /* No negative values (to prevent underflow, as val will be 801 * multiplied by 2). 802 */ 803 if (val < 0) 804 val = 0; 805 goto set_sndbuf; 806 807 case SO_RCVBUF: 808 /* Don't error on this BSD doesn't and if you think 809 * about it this is right. Otherwise apps have to 810 * play 'guess the biggest size' games. RCVBUF/SNDBUF 811 * are treated in BSD as hints 812 */ 813 val = min_t(u32, val, sysctl_rmem_max); 814 set_rcvbuf: 815 /* Ensure val * 2 fits into an int, to prevent max_t() 816 * from treating it as a negative value. 817 */ 818 val = min_t(int, val, INT_MAX / 2); 819 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 820 /* 821 * We double it on the way in to account for 822 * "struct sk_buff" etc. overhead. Applications 823 * assume that the SO_RCVBUF setting they make will 824 * allow that much actual data to be received on that 825 * socket. 826 * 827 * Applications are unaware that "struct sk_buff" and 828 * other overheads allocate from the receive buffer 829 * during socket buffer allocation. 830 * 831 * And after considering the possible alternatives, 832 * returning the value we actually used in getsockopt 833 * is the most desirable behavior. 834 */ 835 sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF); 836 break; 837 838 case SO_RCVBUFFORCE: 839 if (!capable(CAP_NET_ADMIN)) { 840 ret = -EPERM; 841 break; 842 } 843 844 /* No negative values (to prevent underflow, as val will be 845 * multiplied by 2). 846 */ 847 if (val < 0) 848 val = 0; 849 goto set_rcvbuf; 850 851 case SO_KEEPALIVE: 852 if (sk->sk_prot->keepalive) 853 sk->sk_prot->keepalive(sk, valbool); 854 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 855 break; 856 857 case SO_OOBINLINE: 858 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 859 break; 860 861 case SO_NO_CHECK: 862 sk->sk_no_check_tx = valbool; 863 break; 864 865 case SO_PRIORITY: 866 if ((val >= 0 && val <= 6) || 867 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 868 sk->sk_priority = val; 869 else 870 ret = -EPERM; 871 break; 872 873 case SO_LINGER: 874 if (optlen < sizeof(ling)) { 875 ret = -EINVAL; /* 1003.1g */ 876 break; 877 } 878 if (copy_from_user(&ling, optval, sizeof(ling))) { 879 ret = -EFAULT; 880 break; 881 } 882 if (!ling.l_onoff) 883 sock_reset_flag(sk, SOCK_LINGER); 884 else { 885 #if (BITS_PER_LONG == 32) 886 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 887 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 888 else 889 #endif 890 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 891 sock_set_flag(sk, SOCK_LINGER); 892 } 893 break; 894 895 case SO_BSDCOMPAT: 896 sock_warn_obsolete_bsdism("setsockopt"); 897 break; 898 899 case SO_PASSCRED: 900 if (valbool) 901 set_bit(SOCK_PASSCRED, &sock->flags); 902 else 903 clear_bit(SOCK_PASSCRED, &sock->flags); 904 break; 905 906 case SO_TIMESTAMP_OLD: 907 case SO_TIMESTAMP_NEW: 908 case SO_TIMESTAMPNS_OLD: 909 case SO_TIMESTAMPNS_NEW: 910 if (valbool) { 911 if (optname == SO_TIMESTAMP_NEW || optname == SO_TIMESTAMPNS_NEW) 912 sock_set_flag(sk, SOCK_TSTAMP_NEW); 913 else 914 sock_reset_flag(sk, SOCK_TSTAMP_NEW); 915 916 if (optname == SO_TIMESTAMP_OLD || optname == SO_TIMESTAMP_NEW) 917 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 918 else 919 sock_set_flag(sk, SOCK_RCVTSTAMPNS); 920 sock_set_flag(sk, SOCK_RCVTSTAMP); 921 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 922 } else { 923 sock_reset_flag(sk, SOCK_RCVTSTAMP); 924 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 925 sock_reset_flag(sk, SOCK_TSTAMP_NEW); 926 } 927 break; 928 929 case SO_TIMESTAMPING_NEW: 930 sock_set_flag(sk, SOCK_TSTAMP_NEW); 931 /* fall through */ 932 case SO_TIMESTAMPING_OLD: 933 if (val & ~SOF_TIMESTAMPING_MASK) { 934 ret = -EINVAL; 935 break; 936 } 937 938 if (val & SOF_TIMESTAMPING_OPT_ID && 939 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { 940 if (sk->sk_protocol == IPPROTO_TCP && 941 sk->sk_type == SOCK_STREAM) { 942 if ((1 << sk->sk_state) & 943 (TCPF_CLOSE | TCPF_LISTEN)) { 944 ret = -EINVAL; 945 break; 946 } 947 sk->sk_tskey = tcp_sk(sk)->snd_una; 948 } else { 949 sk->sk_tskey = 0; 950 } 951 } 952 953 if (val & SOF_TIMESTAMPING_OPT_STATS && 954 !(val & SOF_TIMESTAMPING_OPT_TSONLY)) { 955 ret = -EINVAL; 956 break; 957 } 958 959 sk->sk_tsflags = val; 960 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 961 sock_enable_timestamp(sk, 962 SOCK_TIMESTAMPING_RX_SOFTWARE); 963 else { 964 if (optname == SO_TIMESTAMPING_NEW) 965 sock_reset_flag(sk, SOCK_TSTAMP_NEW); 966 967 sock_disable_timestamp(sk, 968 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 969 } 970 break; 971 972 case SO_RCVLOWAT: 973 if (val < 0) 974 val = INT_MAX; 975 if (sock->ops->set_rcvlowat) 976 ret = sock->ops->set_rcvlowat(sk, val); 977 else 978 sk->sk_rcvlowat = val ? : 1; 979 break; 980 981 case SO_RCVTIMEO_OLD: 982 case SO_RCVTIMEO_NEW: 983 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen, optname == SO_RCVTIMEO_OLD); 984 break; 985 986 case SO_SNDTIMEO_OLD: 987 case SO_SNDTIMEO_NEW: 988 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen, optname == SO_SNDTIMEO_OLD); 989 break; 990 991 case SO_ATTACH_FILTER: 992 ret = -EINVAL; 993 if (optlen == sizeof(struct sock_fprog)) { 994 struct sock_fprog fprog; 995 996 ret = -EFAULT; 997 if (copy_from_user(&fprog, optval, sizeof(fprog))) 998 break; 999 1000 ret = sk_attach_filter(&fprog, sk); 1001 } 1002 break; 1003 1004 case SO_ATTACH_BPF: 1005 ret = -EINVAL; 1006 if (optlen == sizeof(u32)) { 1007 u32 ufd; 1008 1009 ret = -EFAULT; 1010 if (copy_from_user(&ufd, optval, sizeof(ufd))) 1011 break; 1012 1013 ret = sk_attach_bpf(ufd, sk); 1014 } 1015 break; 1016 1017 case SO_ATTACH_REUSEPORT_CBPF: 1018 ret = -EINVAL; 1019 if (optlen == sizeof(struct sock_fprog)) { 1020 struct sock_fprog fprog; 1021 1022 ret = -EFAULT; 1023 if (copy_from_user(&fprog, optval, sizeof(fprog))) 1024 break; 1025 1026 ret = sk_reuseport_attach_filter(&fprog, sk); 1027 } 1028 break; 1029 1030 case SO_ATTACH_REUSEPORT_EBPF: 1031 ret = -EINVAL; 1032 if (optlen == sizeof(u32)) { 1033 u32 ufd; 1034 1035 ret = -EFAULT; 1036 if (copy_from_user(&ufd, optval, sizeof(ufd))) 1037 break; 1038 1039 ret = sk_reuseport_attach_bpf(ufd, sk); 1040 } 1041 break; 1042 1043 case SO_DETACH_REUSEPORT_BPF: 1044 ret = reuseport_detach_prog(sk); 1045 break; 1046 1047 case SO_DETACH_FILTER: 1048 ret = sk_detach_filter(sk); 1049 break; 1050 1051 case SO_LOCK_FILTER: 1052 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 1053 ret = -EPERM; 1054 else 1055 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 1056 break; 1057 1058 case SO_PASSSEC: 1059 if (valbool) 1060 set_bit(SOCK_PASSSEC, &sock->flags); 1061 else 1062 clear_bit(SOCK_PASSSEC, &sock->flags); 1063 break; 1064 case SO_MARK: 1065 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1066 ret = -EPERM; 1067 } else if (val != sk->sk_mark) { 1068 sk->sk_mark = val; 1069 sk_dst_reset(sk); 1070 } 1071 break; 1072 1073 case SO_RXQ_OVFL: 1074 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 1075 break; 1076 1077 case SO_WIFI_STATUS: 1078 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 1079 break; 1080 1081 case SO_PEEK_OFF: 1082 if (sock->ops->set_peek_off) 1083 ret = sock->ops->set_peek_off(sk, val); 1084 else 1085 ret = -EOPNOTSUPP; 1086 break; 1087 1088 case SO_NOFCS: 1089 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 1090 break; 1091 1092 case SO_SELECT_ERR_QUEUE: 1093 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 1094 break; 1095 1096 #ifdef CONFIG_NET_RX_BUSY_POLL 1097 case SO_BUSY_POLL: 1098 /* allow unprivileged users to decrease the value */ 1099 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN)) 1100 ret = -EPERM; 1101 else { 1102 if (val < 0) 1103 ret = -EINVAL; 1104 else 1105 sk->sk_ll_usec = val; 1106 } 1107 break; 1108 #endif 1109 1110 case SO_MAX_PACING_RATE: 1111 { 1112 unsigned long ulval = (val == ~0U) ? ~0UL : val; 1113 1114 if (sizeof(ulval) != sizeof(val) && 1115 optlen >= sizeof(ulval) && 1116 get_user(ulval, (unsigned long __user *)optval)) { 1117 ret = -EFAULT; 1118 break; 1119 } 1120 if (ulval != ~0UL) 1121 cmpxchg(&sk->sk_pacing_status, 1122 SK_PACING_NONE, 1123 SK_PACING_NEEDED); 1124 sk->sk_max_pacing_rate = ulval; 1125 sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval); 1126 break; 1127 } 1128 case SO_INCOMING_CPU: 1129 sk->sk_incoming_cpu = val; 1130 break; 1131 1132 case SO_CNX_ADVICE: 1133 if (val == 1) 1134 dst_negative_advice(sk); 1135 break; 1136 1137 case SO_ZEROCOPY: 1138 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) { 1139 if (!((sk->sk_type == SOCK_STREAM && 1140 sk->sk_protocol == IPPROTO_TCP) || 1141 (sk->sk_type == SOCK_DGRAM && 1142 sk->sk_protocol == IPPROTO_UDP))) 1143 ret = -ENOTSUPP; 1144 } else if (sk->sk_family != PF_RDS) { 1145 ret = -ENOTSUPP; 1146 } 1147 if (!ret) { 1148 if (val < 0 || val > 1) 1149 ret = -EINVAL; 1150 else 1151 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool); 1152 } 1153 break; 1154 1155 case SO_TXTIME: 1156 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1157 ret = -EPERM; 1158 } else if (optlen != sizeof(struct sock_txtime)) { 1159 ret = -EINVAL; 1160 } else if (copy_from_user(&sk_txtime, optval, 1161 sizeof(struct sock_txtime))) { 1162 ret = -EFAULT; 1163 } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) { 1164 ret = -EINVAL; 1165 } else { 1166 sock_valbool_flag(sk, SOCK_TXTIME, true); 1167 sk->sk_clockid = sk_txtime.clockid; 1168 sk->sk_txtime_deadline_mode = 1169 !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE); 1170 sk->sk_txtime_report_errors = 1171 !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS); 1172 } 1173 break; 1174 1175 case SO_BINDTOIFINDEX: 1176 ret = sock_setbindtodevice_locked(sk, val); 1177 break; 1178 1179 default: 1180 ret = -ENOPROTOOPT; 1181 break; 1182 } 1183 release_sock(sk); 1184 return ret; 1185 } 1186 EXPORT_SYMBOL(sock_setsockopt); 1187 1188 1189 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 1190 struct ucred *ucred) 1191 { 1192 ucred->pid = pid_vnr(pid); 1193 ucred->uid = ucred->gid = -1; 1194 if (cred) { 1195 struct user_namespace *current_ns = current_user_ns(); 1196 1197 ucred->uid = from_kuid_munged(current_ns, cred->euid); 1198 ucred->gid = from_kgid_munged(current_ns, cred->egid); 1199 } 1200 } 1201 1202 static int groups_to_user(gid_t __user *dst, const struct group_info *src) 1203 { 1204 struct user_namespace *user_ns = current_user_ns(); 1205 int i; 1206 1207 for (i = 0; i < src->ngroups; i++) 1208 if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i)) 1209 return -EFAULT; 1210 1211 return 0; 1212 } 1213 1214 int sock_getsockopt(struct socket *sock, int level, int optname, 1215 char __user *optval, int __user *optlen) 1216 { 1217 struct sock *sk = sock->sk; 1218 1219 union { 1220 int val; 1221 u64 val64; 1222 unsigned long ulval; 1223 struct linger ling; 1224 struct old_timeval32 tm32; 1225 struct __kernel_old_timeval tm; 1226 struct __kernel_sock_timeval stm; 1227 struct sock_txtime txtime; 1228 } v; 1229 1230 int lv = sizeof(int); 1231 int len; 1232 1233 if (get_user(len, optlen)) 1234 return -EFAULT; 1235 if (len < 0) 1236 return -EINVAL; 1237 1238 memset(&v, 0, sizeof(v)); 1239 1240 switch (optname) { 1241 case SO_DEBUG: 1242 v.val = sock_flag(sk, SOCK_DBG); 1243 break; 1244 1245 case SO_DONTROUTE: 1246 v.val = sock_flag(sk, SOCK_LOCALROUTE); 1247 break; 1248 1249 case SO_BROADCAST: 1250 v.val = sock_flag(sk, SOCK_BROADCAST); 1251 break; 1252 1253 case SO_SNDBUF: 1254 v.val = sk->sk_sndbuf; 1255 break; 1256 1257 case SO_RCVBUF: 1258 v.val = sk->sk_rcvbuf; 1259 break; 1260 1261 case SO_REUSEADDR: 1262 v.val = sk->sk_reuse; 1263 break; 1264 1265 case SO_REUSEPORT: 1266 v.val = sk->sk_reuseport; 1267 break; 1268 1269 case SO_KEEPALIVE: 1270 v.val = sock_flag(sk, SOCK_KEEPOPEN); 1271 break; 1272 1273 case SO_TYPE: 1274 v.val = sk->sk_type; 1275 break; 1276 1277 case SO_PROTOCOL: 1278 v.val = sk->sk_protocol; 1279 break; 1280 1281 case SO_DOMAIN: 1282 v.val = sk->sk_family; 1283 break; 1284 1285 case SO_ERROR: 1286 v.val = -sock_error(sk); 1287 if (v.val == 0) 1288 v.val = xchg(&sk->sk_err_soft, 0); 1289 break; 1290 1291 case SO_OOBINLINE: 1292 v.val = sock_flag(sk, SOCK_URGINLINE); 1293 break; 1294 1295 case SO_NO_CHECK: 1296 v.val = sk->sk_no_check_tx; 1297 break; 1298 1299 case SO_PRIORITY: 1300 v.val = sk->sk_priority; 1301 break; 1302 1303 case SO_LINGER: 1304 lv = sizeof(v.ling); 1305 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1306 v.ling.l_linger = sk->sk_lingertime / HZ; 1307 break; 1308 1309 case SO_BSDCOMPAT: 1310 sock_warn_obsolete_bsdism("getsockopt"); 1311 break; 1312 1313 case SO_TIMESTAMP_OLD: 1314 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1315 !sock_flag(sk, SOCK_TSTAMP_NEW) && 1316 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1317 break; 1318 1319 case SO_TIMESTAMPNS_OLD: 1320 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW); 1321 break; 1322 1323 case SO_TIMESTAMP_NEW: 1324 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW); 1325 break; 1326 1327 case SO_TIMESTAMPNS_NEW: 1328 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW); 1329 break; 1330 1331 case SO_TIMESTAMPING_OLD: 1332 v.val = sk->sk_tsflags; 1333 break; 1334 1335 case SO_RCVTIMEO_OLD: 1336 case SO_RCVTIMEO_NEW: 1337 lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname); 1338 break; 1339 1340 case SO_SNDTIMEO_OLD: 1341 case SO_SNDTIMEO_NEW: 1342 lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname); 1343 break; 1344 1345 case SO_RCVLOWAT: 1346 v.val = sk->sk_rcvlowat; 1347 break; 1348 1349 case SO_SNDLOWAT: 1350 v.val = 1; 1351 break; 1352 1353 case SO_PASSCRED: 1354 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1355 break; 1356 1357 case SO_PEERCRED: 1358 { 1359 struct ucred peercred; 1360 if (len > sizeof(peercred)) 1361 len = sizeof(peercred); 1362 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1363 if (copy_to_user(optval, &peercred, len)) 1364 return -EFAULT; 1365 goto lenout; 1366 } 1367 1368 case SO_PEERGROUPS: 1369 { 1370 int ret, n; 1371 1372 if (!sk->sk_peer_cred) 1373 return -ENODATA; 1374 1375 n = sk->sk_peer_cred->group_info->ngroups; 1376 if (len < n * sizeof(gid_t)) { 1377 len = n * sizeof(gid_t); 1378 return put_user(len, optlen) ? -EFAULT : -ERANGE; 1379 } 1380 len = n * sizeof(gid_t); 1381 1382 ret = groups_to_user((gid_t __user *)optval, 1383 sk->sk_peer_cred->group_info); 1384 if (ret) 1385 return ret; 1386 goto lenout; 1387 } 1388 1389 case SO_PEERNAME: 1390 { 1391 char address[128]; 1392 1393 lv = sock->ops->getname(sock, (struct sockaddr *)address, 2); 1394 if (lv < 0) 1395 return -ENOTCONN; 1396 if (lv < len) 1397 return -EINVAL; 1398 if (copy_to_user(optval, address, len)) 1399 return -EFAULT; 1400 goto lenout; 1401 } 1402 1403 /* Dubious BSD thing... Probably nobody even uses it, but 1404 * the UNIX standard wants it for whatever reason... -DaveM 1405 */ 1406 case SO_ACCEPTCONN: 1407 v.val = sk->sk_state == TCP_LISTEN; 1408 break; 1409 1410 case SO_PASSSEC: 1411 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1412 break; 1413 1414 case SO_PEERSEC: 1415 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1416 1417 case SO_MARK: 1418 v.val = sk->sk_mark; 1419 break; 1420 1421 case SO_RXQ_OVFL: 1422 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1423 break; 1424 1425 case SO_WIFI_STATUS: 1426 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1427 break; 1428 1429 case SO_PEEK_OFF: 1430 if (!sock->ops->set_peek_off) 1431 return -EOPNOTSUPP; 1432 1433 v.val = sk->sk_peek_off; 1434 break; 1435 case SO_NOFCS: 1436 v.val = sock_flag(sk, SOCK_NOFCS); 1437 break; 1438 1439 case SO_BINDTODEVICE: 1440 return sock_getbindtodevice(sk, optval, optlen, len); 1441 1442 case SO_GET_FILTER: 1443 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1444 if (len < 0) 1445 return len; 1446 1447 goto lenout; 1448 1449 case SO_LOCK_FILTER: 1450 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1451 break; 1452 1453 case SO_BPF_EXTENSIONS: 1454 v.val = bpf_tell_extensions(); 1455 break; 1456 1457 case SO_SELECT_ERR_QUEUE: 1458 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1459 break; 1460 1461 #ifdef CONFIG_NET_RX_BUSY_POLL 1462 case SO_BUSY_POLL: 1463 v.val = sk->sk_ll_usec; 1464 break; 1465 #endif 1466 1467 case SO_MAX_PACING_RATE: 1468 if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) { 1469 lv = sizeof(v.ulval); 1470 v.ulval = sk->sk_max_pacing_rate; 1471 } else { 1472 /* 32bit version */ 1473 v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U); 1474 } 1475 break; 1476 1477 case SO_INCOMING_CPU: 1478 v.val = sk->sk_incoming_cpu; 1479 break; 1480 1481 case SO_MEMINFO: 1482 { 1483 u32 meminfo[SK_MEMINFO_VARS]; 1484 1485 sk_get_meminfo(sk, meminfo); 1486 1487 len = min_t(unsigned int, len, sizeof(meminfo)); 1488 if (copy_to_user(optval, &meminfo, len)) 1489 return -EFAULT; 1490 1491 goto lenout; 1492 } 1493 1494 #ifdef CONFIG_NET_RX_BUSY_POLL 1495 case SO_INCOMING_NAPI_ID: 1496 v.val = READ_ONCE(sk->sk_napi_id); 1497 1498 /* aggregate non-NAPI IDs down to 0 */ 1499 if (v.val < MIN_NAPI_ID) 1500 v.val = 0; 1501 1502 break; 1503 #endif 1504 1505 case SO_COOKIE: 1506 lv = sizeof(u64); 1507 if (len < lv) 1508 return -EINVAL; 1509 v.val64 = sock_gen_cookie(sk); 1510 break; 1511 1512 case SO_ZEROCOPY: 1513 v.val = sock_flag(sk, SOCK_ZEROCOPY); 1514 break; 1515 1516 case SO_TXTIME: 1517 lv = sizeof(v.txtime); 1518 v.txtime.clockid = sk->sk_clockid; 1519 v.txtime.flags |= sk->sk_txtime_deadline_mode ? 1520 SOF_TXTIME_DEADLINE_MODE : 0; 1521 v.txtime.flags |= sk->sk_txtime_report_errors ? 1522 SOF_TXTIME_REPORT_ERRORS : 0; 1523 break; 1524 1525 case SO_BINDTOIFINDEX: 1526 v.val = sk->sk_bound_dev_if; 1527 break; 1528 1529 default: 1530 /* We implement the SO_SNDLOWAT etc to not be settable 1531 * (1003.1g 7). 1532 */ 1533 return -ENOPROTOOPT; 1534 } 1535 1536 if (len > lv) 1537 len = lv; 1538 if (copy_to_user(optval, &v, len)) 1539 return -EFAULT; 1540 lenout: 1541 if (put_user(len, optlen)) 1542 return -EFAULT; 1543 return 0; 1544 } 1545 1546 /* 1547 * Initialize an sk_lock. 1548 * 1549 * (We also register the sk_lock with the lock validator.) 1550 */ 1551 static inline void sock_lock_init(struct sock *sk) 1552 { 1553 if (sk->sk_kern_sock) 1554 sock_lock_init_class_and_name( 1555 sk, 1556 af_family_kern_slock_key_strings[sk->sk_family], 1557 af_family_kern_slock_keys + sk->sk_family, 1558 af_family_kern_key_strings[sk->sk_family], 1559 af_family_kern_keys + sk->sk_family); 1560 else 1561 sock_lock_init_class_and_name( 1562 sk, 1563 af_family_slock_key_strings[sk->sk_family], 1564 af_family_slock_keys + sk->sk_family, 1565 af_family_key_strings[sk->sk_family], 1566 af_family_keys + sk->sk_family); 1567 } 1568 1569 /* 1570 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1571 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1572 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1573 */ 1574 static void sock_copy(struct sock *nsk, const struct sock *osk) 1575 { 1576 #ifdef CONFIG_SECURITY_NETWORK 1577 void *sptr = nsk->sk_security; 1578 #endif 1579 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1580 1581 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1582 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1583 1584 #ifdef CONFIG_SECURITY_NETWORK 1585 nsk->sk_security = sptr; 1586 security_sk_clone(osk, nsk); 1587 #endif 1588 } 1589 1590 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1591 int family) 1592 { 1593 struct sock *sk; 1594 struct kmem_cache *slab; 1595 1596 slab = prot->slab; 1597 if (slab != NULL) { 1598 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1599 if (!sk) 1600 return sk; 1601 if (want_init_on_alloc(priority)) 1602 sk_prot_clear_nulls(sk, prot->obj_size); 1603 } else 1604 sk = kmalloc(prot->obj_size, priority); 1605 1606 if (sk != NULL) { 1607 if (security_sk_alloc(sk, family, priority)) 1608 goto out_free; 1609 1610 if (!try_module_get(prot->owner)) 1611 goto out_free_sec; 1612 sk_tx_queue_clear(sk); 1613 } 1614 1615 return sk; 1616 1617 out_free_sec: 1618 security_sk_free(sk); 1619 out_free: 1620 if (slab != NULL) 1621 kmem_cache_free(slab, sk); 1622 else 1623 kfree(sk); 1624 return NULL; 1625 } 1626 1627 static void sk_prot_free(struct proto *prot, struct sock *sk) 1628 { 1629 struct kmem_cache *slab; 1630 struct module *owner; 1631 1632 owner = prot->owner; 1633 slab = prot->slab; 1634 1635 cgroup_sk_free(&sk->sk_cgrp_data); 1636 mem_cgroup_sk_free(sk); 1637 security_sk_free(sk); 1638 if (slab != NULL) 1639 kmem_cache_free(slab, sk); 1640 else 1641 kfree(sk); 1642 module_put(owner); 1643 } 1644 1645 /** 1646 * sk_alloc - All socket objects are allocated here 1647 * @net: the applicable net namespace 1648 * @family: protocol family 1649 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1650 * @prot: struct proto associated with this new sock instance 1651 * @kern: is this to be a kernel socket? 1652 */ 1653 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1654 struct proto *prot, int kern) 1655 { 1656 struct sock *sk; 1657 1658 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1659 if (sk) { 1660 sk->sk_family = family; 1661 /* 1662 * See comment in struct sock definition to understand 1663 * why we need sk_prot_creator -acme 1664 */ 1665 sk->sk_prot = sk->sk_prot_creator = prot; 1666 sk->sk_kern_sock = kern; 1667 sock_lock_init(sk); 1668 sk->sk_net_refcnt = kern ? 0 : 1; 1669 if (likely(sk->sk_net_refcnt)) { 1670 get_net(net); 1671 sock_inuse_add(net, 1); 1672 } 1673 1674 sock_net_set(sk, net); 1675 refcount_set(&sk->sk_wmem_alloc, 1); 1676 1677 mem_cgroup_sk_alloc(sk); 1678 cgroup_sk_alloc(&sk->sk_cgrp_data); 1679 sock_update_classid(&sk->sk_cgrp_data); 1680 sock_update_netprioidx(&sk->sk_cgrp_data); 1681 } 1682 1683 return sk; 1684 } 1685 EXPORT_SYMBOL(sk_alloc); 1686 1687 /* Sockets having SOCK_RCU_FREE will call this function after one RCU 1688 * grace period. This is the case for UDP sockets and TCP listeners. 1689 */ 1690 static void __sk_destruct(struct rcu_head *head) 1691 { 1692 struct sock *sk = container_of(head, struct sock, sk_rcu); 1693 struct sk_filter *filter; 1694 1695 if (sk->sk_destruct) 1696 sk->sk_destruct(sk); 1697 1698 filter = rcu_dereference_check(sk->sk_filter, 1699 refcount_read(&sk->sk_wmem_alloc) == 0); 1700 if (filter) { 1701 sk_filter_uncharge(sk, filter); 1702 RCU_INIT_POINTER(sk->sk_filter, NULL); 1703 } 1704 1705 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1706 1707 #ifdef CONFIG_BPF_SYSCALL 1708 bpf_sk_storage_free(sk); 1709 #endif 1710 1711 if (atomic_read(&sk->sk_omem_alloc)) 1712 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1713 __func__, atomic_read(&sk->sk_omem_alloc)); 1714 1715 if (sk->sk_frag.page) { 1716 put_page(sk->sk_frag.page); 1717 sk->sk_frag.page = NULL; 1718 } 1719 1720 if (sk->sk_peer_cred) 1721 put_cred(sk->sk_peer_cred); 1722 put_pid(sk->sk_peer_pid); 1723 if (likely(sk->sk_net_refcnt)) 1724 put_net(sock_net(sk)); 1725 sk_prot_free(sk->sk_prot_creator, sk); 1726 } 1727 1728 void sk_destruct(struct sock *sk) 1729 { 1730 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE); 1731 1732 if (rcu_access_pointer(sk->sk_reuseport_cb)) { 1733 reuseport_detach_sock(sk); 1734 use_call_rcu = true; 1735 } 1736 1737 if (use_call_rcu) 1738 call_rcu(&sk->sk_rcu, __sk_destruct); 1739 else 1740 __sk_destruct(&sk->sk_rcu); 1741 } 1742 1743 static void __sk_free(struct sock *sk) 1744 { 1745 if (likely(sk->sk_net_refcnt)) 1746 sock_inuse_add(sock_net(sk), -1); 1747 1748 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk))) 1749 sock_diag_broadcast_destroy(sk); 1750 else 1751 sk_destruct(sk); 1752 } 1753 1754 void sk_free(struct sock *sk) 1755 { 1756 /* 1757 * We subtract one from sk_wmem_alloc and can know if 1758 * some packets are still in some tx queue. 1759 * If not null, sock_wfree() will call __sk_free(sk) later 1760 */ 1761 if (refcount_dec_and_test(&sk->sk_wmem_alloc)) 1762 __sk_free(sk); 1763 } 1764 EXPORT_SYMBOL(sk_free); 1765 1766 static void sk_init_common(struct sock *sk) 1767 { 1768 skb_queue_head_init(&sk->sk_receive_queue); 1769 skb_queue_head_init(&sk->sk_write_queue); 1770 skb_queue_head_init(&sk->sk_error_queue); 1771 1772 rwlock_init(&sk->sk_callback_lock); 1773 lockdep_set_class_and_name(&sk->sk_receive_queue.lock, 1774 af_rlock_keys + sk->sk_family, 1775 af_family_rlock_key_strings[sk->sk_family]); 1776 lockdep_set_class_and_name(&sk->sk_write_queue.lock, 1777 af_wlock_keys + sk->sk_family, 1778 af_family_wlock_key_strings[sk->sk_family]); 1779 lockdep_set_class_and_name(&sk->sk_error_queue.lock, 1780 af_elock_keys + sk->sk_family, 1781 af_family_elock_key_strings[sk->sk_family]); 1782 lockdep_set_class_and_name(&sk->sk_callback_lock, 1783 af_callback_keys + sk->sk_family, 1784 af_family_clock_key_strings[sk->sk_family]); 1785 } 1786 1787 /** 1788 * sk_clone_lock - clone a socket, and lock its clone 1789 * @sk: the socket to clone 1790 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1791 * 1792 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1793 */ 1794 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1795 { 1796 struct sock *newsk; 1797 bool is_charged = true; 1798 1799 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1800 if (newsk != NULL) { 1801 struct sk_filter *filter; 1802 1803 sock_copy(newsk, sk); 1804 1805 newsk->sk_prot_creator = sk->sk_prot; 1806 1807 /* SANITY */ 1808 if (likely(newsk->sk_net_refcnt)) 1809 get_net(sock_net(newsk)); 1810 sk_node_init(&newsk->sk_node); 1811 sock_lock_init(newsk); 1812 bh_lock_sock(newsk); 1813 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1814 newsk->sk_backlog.len = 0; 1815 1816 atomic_set(&newsk->sk_rmem_alloc, 0); 1817 /* 1818 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1819 */ 1820 refcount_set(&newsk->sk_wmem_alloc, 1); 1821 atomic_set(&newsk->sk_omem_alloc, 0); 1822 sk_init_common(newsk); 1823 1824 newsk->sk_dst_cache = NULL; 1825 newsk->sk_dst_pending_confirm = 0; 1826 newsk->sk_wmem_queued = 0; 1827 newsk->sk_forward_alloc = 0; 1828 atomic_set(&newsk->sk_drops, 0); 1829 newsk->sk_send_head = NULL; 1830 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1831 atomic_set(&newsk->sk_zckey, 0); 1832 1833 sock_reset_flag(newsk, SOCK_DONE); 1834 mem_cgroup_sk_alloc(newsk); 1835 cgroup_sk_alloc(&newsk->sk_cgrp_data); 1836 1837 rcu_read_lock(); 1838 filter = rcu_dereference(sk->sk_filter); 1839 if (filter != NULL) 1840 /* though it's an empty new sock, the charging may fail 1841 * if sysctl_optmem_max was changed between creation of 1842 * original socket and cloning 1843 */ 1844 is_charged = sk_filter_charge(newsk, filter); 1845 RCU_INIT_POINTER(newsk->sk_filter, filter); 1846 rcu_read_unlock(); 1847 1848 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) { 1849 /* We need to make sure that we don't uncharge the new 1850 * socket if we couldn't charge it in the first place 1851 * as otherwise we uncharge the parent's filter. 1852 */ 1853 if (!is_charged) 1854 RCU_INIT_POINTER(newsk->sk_filter, NULL); 1855 sk_free_unlock_clone(newsk); 1856 newsk = NULL; 1857 goto out; 1858 } 1859 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL); 1860 1861 if (bpf_sk_storage_clone(sk, newsk)) { 1862 sk_free_unlock_clone(newsk); 1863 newsk = NULL; 1864 goto out; 1865 } 1866 1867 newsk->sk_err = 0; 1868 newsk->sk_err_soft = 0; 1869 newsk->sk_priority = 0; 1870 newsk->sk_incoming_cpu = raw_smp_processor_id(); 1871 if (likely(newsk->sk_net_refcnt)) 1872 sock_inuse_add(sock_net(newsk), 1); 1873 1874 /* 1875 * Before updating sk_refcnt, we must commit prior changes to memory 1876 * (Documentation/RCU/rculist_nulls.txt for details) 1877 */ 1878 smp_wmb(); 1879 refcount_set(&newsk->sk_refcnt, 2); 1880 1881 /* 1882 * Increment the counter in the same struct proto as the master 1883 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1884 * is the same as sk->sk_prot->socks, as this field was copied 1885 * with memcpy). 1886 * 1887 * This _changes_ the previous behaviour, where 1888 * tcp_create_openreq_child always was incrementing the 1889 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1890 * to be taken into account in all callers. -acme 1891 */ 1892 sk_refcnt_debug_inc(newsk); 1893 sk_set_socket(newsk, NULL); 1894 RCU_INIT_POINTER(newsk->sk_wq, NULL); 1895 1896 if (newsk->sk_prot->sockets_allocated) 1897 sk_sockets_allocated_inc(newsk); 1898 1899 if (sock_needs_netstamp(sk) && 1900 newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1901 net_enable_timestamp(); 1902 } 1903 out: 1904 return newsk; 1905 } 1906 EXPORT_SYMBOL_GPL(sk_clone_lock); 1907 1908 void sk_free_unlock_clone(struct sock *sk) 1909 { 1910 /* It is still raw copy of parent, so invalidate 1911 * destructor and make plain sk_free() */ 1912 sk->sk_destruct = NULL; 1913 bh_unlock_sock(sk); 1914 sk_free(sk); 1915 } 1916 EXPORT_SYMBOL_GPL(sk_free_unlock_clone); 1917 1918 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1919 { 1920 u32 max_segs = 1; 1921 1922 sk_dst_set(sk, dst); 1923 sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps; 1924 if (sk->sk_route_caps & NETIF_F_GSO) 1925 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1926 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1927 if (sk_can_gso(sk)) { 1928 if (dst->header_len && !xfrm_dst_offload_ok(dst)) { 1929 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1930 } else { 1931 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1932 sk->sk_gso_max_size = dst->dev->gso_max_size; 1933 max_segs = max_t(u32, dst->dev->gso_max_segs, 1); 1934 } 1935 } 1936 sk->sk_gso_max_segs = max_segs; 1937 } 1938 EXPORT_SYMBOL_GPL(sk_setup_caps); 1939 1940 /* 1941 * Simple resource managers for sockets. 1942 */ 1943 1944 1945 /* 1946 * Write buffer destructor automatically called from kfree_skb. 1947 */ 1948 void sock_wfree(struct sk_buff *skb) 1949 { 1950 struct sock *sk = skb->sk; 1951 unsigned int len = skb->truesize; 1952 1953 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1954 /* 1955 * Keep a reference on sk_wmem_alloc, this will be released 1956 * after sk_write_space() call 1957 */ 1958 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc)); 1959 sk->sk_write_space(sk); 1960 len = 1; 1961 } 1962 /* 1963 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1964 * could not do because of in-flight packets 1965 */ 1966 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc)) 1967 __sk_free(sk); 1968 } 1969 EXPORT_SYMBOL(sock_wfree); 1970 1971 /* This variant of sock_wfree() is used by TCP, 1972 * since it sets SOCK_USE_WRITE_QUEUE. 1973 */ 1974 void __sock_wfree(struct sk_buff *skb) 1975 { 1976 struct sock *sk = skb->sk; 1977 1978 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc)) 1979 __sk_free(sk); 1980 } 1981 1982 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) 1983 { 1984 skb_orphan(skb); 1985 skb->sk = sk; 1986 #ifdef CONFIG_INET 1987 if (unlikely(!sk_fullsock(sk))) { 1988 skb->destructor = sock_edemux; 1989 sock_hold(sk); 1990 return; 1991 } 1992 #endif 1993 skb->destructor = sock_wfree; 1994 skb_set_hash_from_sk(skb, sk); 1995 /* 1996 * We used to take a refcount on sk, but following operation 1997 * is enough to guarantee sk_free() wont free this sock until 1998 * all in-flight packets are completed 1999 */ 2000 refcount_add(skb->truesize, &sk->sk_wmem_alloc); 2001 } 2002 EXPORT_SYMBOL(skb_set_owner_w); 2003 2004 static bool can_skb_orphan_partial(const struct sk_buff *skb) 2005 { 2006 #ifdef CONFIG_TLS_DEVICE 2007 /* Drivers depend on in-order delivery for crypto offload, 2008 * partial orphan breaks out-of-order-OK logic. 2009 */ 2010 if (skb->decrypted) 2011 return false; 2012 #endif 2013 return (skb->destructor == sock_wfree || 2014 (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree)); 2015 } 2016 2017 /* This helper is used by netem, as it can hold packets in its 2018 * delay queue. We want to allow the owner socket to send more 2019 * packets, as if they were already TX completed by a typical driver. 2020 * But we also want to keep skb->sk set because some packet schedulers 2021 * rely on it (sch_fq for example). 2022 */ 2023 void skb_orphan_partial(struct sk_buff *skb) 2024 { 2025 if (skb_is_tcp_pure_ack(skb)) 2026 return; 2027 2028 if (can_skb_orphan_partial(skb)) { 2029 struct sock *sk = skb->sk; 2030 2031 if (refcount_inc_not_zero(&sk->sk_refcnt)) { 2032 WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc)); 2033 skb->destructor = sock_efree; 2034 } 2035 } else { 2036 skb_orphan(skb); 2037 } 2038 } 2039 EXPORT_SYMBOL(skb_orphan_partial); 2040 2041 /* 2042 * Read buffer destructor automatically called from kfree_skb. 2043 */ 2044 void sock_rfree(struct sk_buff *skb) 2045 { 2046 struct sock *sk = skb->sk; 2047 unsigned int len = skb->truesize; 2048 2049 atomic_sub(len, &sk->sk_rmem_alloc); 2050 sk_mem_uncharge(sk, len); 2051 } 2052 EXPORT_SYMBOL(sock_rfree); 2053 2054 /* 2055 * Buffer destructor for skbs that are not used directly in read or write 2056 * path, e.g. for error handler skbs. Automatically called from kfree_skb. 2057 */ 2058 void sock_efree(struct sk_buff *skb) 2059 { 2060 sock_put(skb->sk); 2061 } 2062 EXPORT_SYMBOL(sock_efree); 2063 2064 kuid_t sock_i_uid(struct sock *sk) 2065 { 2066 kuid_t uid; 2067 2068 read_lock_bh(&sk->sk_callback_lock); 2069 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 2070 read_unlock_bh(&sk->sk_callback_lock); 2071 return uid; 2072 } 2073 EXPORT_SYMBOL(sock_i_uid); 2074 2075 unsigned long sock_i_ino(struct sock *sk) 2076 { 2077 unsigned long ino; 2078 2079 read_lock_bh(&sk->sk_callback_lock); 2080 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 2081 read_unlock_bh(&sk->sk_callback_lock); 2082 return ino; 2083 } 2084 EXPORT_SYMBOL(sock_i_ino); 2085 2086 /* 2087 * Allocate a skb from the socket's send buffer. 2088 */ 2089 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 2090 gfp_t priority) 2091 { 2092 if (force || refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 2093 struct sk_buff *skb = alloc_skb(size, priority); 2094 if (skb) { 2095 skb_set_owner_w(skb, sk); 2096 return skb; 2097 } 2098 } 2099 return NULL; 2100 } 2101 EXPORT_SYMBOL(sock_wmalloc); 2102 2103 static void sock_ofree(struct sk_buff *skb) 2104 { 2105 struct sock *sk = skb->sk; 2106 2107 atomic_sub(skb->truesize, &sk->sk_omem_alloc); 2108 } 2109 2110 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 2111 gfp_t priority) 2112 { 2113 struct sk_buff *skb; 2114 2115 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */ 2116 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) > 2117 sysctl_optmem_max) 2118 return NULL; 2119 2120 skb = alloc_skb(size, priority); 2121 if (!skb) 2122 return NULL; 2123 2124 atomic_add(skb->truesize, &sk->sk_omem_alloc); 2125 skb->sk = sk; 2126 skb->destructor = sock_ofree; 2127 return skb; 2128 } 2129 2130 /* 2131 * Allocate a memory block from the socket's option memory buffer. 2132 */ 2133 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 2134 { 2135 if ((unsigned int)size <= sysctl_optmem_max && 2136 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 2137 void *mem; 2138 /* First do the add, to avoid the race if kmalloc 2139 * might sleep. 2140 */ 2141 atomic_add(size, &sk->sk_omem_alloc); 2142 mem = kmalloc(size, priority); 2143 if (mem) 2144 return mem; 2145 atomic_sub(size, &sk->sk_omem_alloc); 2146 } 2147 return NULL; 2148 } 2149 EXPORT_SYMBOL(sock_kmalloc); 2150 2151 /* Free an option memory block. Note, we actually want the inline 2152 * here as this allows gcc to detect the nullify and fold away the 2153 * condition entirely. 2154 */ 2155 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size, 2156 const bool nullify) 2157 { 2158 if (WARN_ON_ONCE(!mem)) 2159 return; 2160 if (nullify) 2161 kzfree(mem); 2162 else 2163 kfree(mem); 2164 atomic_sub(size, &sk->sk_omem_alloc); 2165 } 2166 2167 void sock_kfree_s(struct sock *sk, void *mem, int size) 2168 { 2169 __sock_kfree_s(sk, mem, size, false); 2170 } 2171 EXPORT_SYMBOL(sock_kfree_s); 2172 2173 void sock_kzfree_s(struct sock *sk, void *mem, int size) 2174 { 2175 __sock_kfree_s(sk, mem, size, true); 2176 } 2177 EXPORT_SYMBOL(sock_kzfree_s); 2178 2179 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 2180 I think, these locks should be removed for datagram sockets. 2181 */ 2182 static long sock_wait_for_wmem(struct sock *sk, long timeo) 2183 { 2184 DEFINE_WAIT(wait); 2185 2186 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); 2187 for (;;) { 2188 if (!timeo) 2189 break; 2190 if (signal_pending(current)) 2191 break; 2192 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 2193 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 2194 if (refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 2195 break; 2196 if (sk->sk_shutdown & SEND_SHUTDOWN) 2197 break; 2198 if (sk->sk_err) 2199 break; 2200 timeo = schedule_timeout(timeo); 2201 } 2202 finish_wait(sk_sleep(sk), &wait); 2203 return timeo; 2204 } 2205 2206 2207 /* 2208 * Generic send/receive buffer handlers 2209 */ 2210 2211 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 2212 unsigned long data_len, int noblock, 2213 int *errcode, int max_page_order) 2214 { 2215 struct sk_buff *skb; 2216 long timeo; 2217 int err; 2218 2219 timeo = sock_sndtimeo(sk, noblock); 2220 for (;;) { 2221 err = sock_error(sk); 2222 if (err != 0) 2223 goto failure; 2224 2225 err = -EPIPE; 2226 if (sk->sk_shutdown & SEND_SHUTDOWN) 2227 goto failure; 2228 2229 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf) 2230 break; 2231 2232 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); 2233 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 2234 err = -EAGAIN; 2235 if (!timeo) 2236 goto failure; 2237 if (signal_pending(current)) 2238 goto interrupted; 2239 timeo = sock_wait_for_wmem(sk, timeo); 2240 } 2241 skb = alloc_skb_with_frags(header_len, data_len, max_page_order, 2242 errcode, sk->sk_allocation); 2243 if (skb) 2244 skb_set_owner_w(skb, sk); 2245 return skb; 2246 2247 interrupted: 2248 err = sock_intr_errno(timeo); 2249 failure: 2250 *errcode = err; 2251 return NULL; 2252 } 2253 EXPORT_SYMBOL(sock_alloc_send_pskb); 2254 2255 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 2256 int noblock, int *errcode) 2257 { 2258 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 2259 } 2260 EXPORT_SYMBOL(sock_alloc_send_skb); 2261 2262 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, 2263 struct sockcm_cookie *sockc) 2264 { 2265 u32 tsflags; 2266 2267 switch (cmsg->cmsg_type) { 2268 case SO_MARK: 2269 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 2270 return -EPERM; 2271 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 2272 return -EINVAL; 2273 sockc->mark = *(u32 *)CMSG_DATA(cmsg); 2274 break; 2275 case SO_TIMESTAMPING_OLD: 2276 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 2277 return -EINVAL; 2278 2279 tsflags = *(u32 *)CMSG_DATA(cmsg); 2280 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK) 2281 return -EINVAL; 2282 2283 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK; 2284 sockc->tsflags |= tsflags; 2285 break; 2286 case SCM_TXTIME: 2287 if (!sock_flag(sk, SOCK_TXTIME)) 2288 return -EINVAL; 2289 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64))) 2290 return -EINVAL; 2291 sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg)); 2292 break; 2293 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */ 2294 case SCM_RIGHTS: 2295 case SCM_CREDENTIALS: 2296 break; 2297 default: 2298 return -EINVAL; 2299 } 2300 return 0; 2301 } 2302 EXPORT_SYMBOL(__sock_cmsg_send); 2303 2304 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 2305 struct sockcm_cookie *sockc) 2306 { 2307 struct cmsghdr *cmsg; 2308 int ret; 2309 2310 for_each_cmsghdr(cmsg, msg) { 2311 if (!CMSG_OK(msg, cmsg)) 2312 return -EINVAL; 2313 if (cmsg->cmsg_level != SOL_SOCKET) 2314 continue; 2315 ret = __sock_cmsg_send(sk, msg, cmsg, sockc); 2316 if (ret) 2317 return ret; 2318 } 2319 return 0; 2320 } 2321 EXPORT_SYMBOL(sock_cmsg_send); 2322 2323 static void sk_enter_memory_pressure(struct sock *sk) 2324 { 2325 if (!sk->sk_prot->enter_memory_pressure) 2326 return; 2327 2328 sk->sk_prot->enter_memory_pressure(sk); 2329 } 2330 2331 static void sk_leave_memory_pressure(struct sock *sk) 2332 { 2333 if (sk->sk_prot->leave_memory_pressure) { 2334 sk->sk_prot->leave_memory_pressure(sk); 2335 } else { 2336 unsigned long *memory_pressure = sk->sk_prot->memory_pressure; 2337 2338 if (memory_pressure && *memory_pressure) 2339 *memory_pressure = 0; 2340 } 2341 } 2342 2343 /* On 32bit arches, an skb frag is limited to 2^15 */ 2344 #define SKB_FRAG_PAGE_ORDER get_order(32768) 2345 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2346 2347 /** 2348 * skb_page_frag_refill - check that a page_frag contains enough room 2349 * @sz: minimum size of the fragment we want to get 2350 * @pfrag: pointer to page_frag 2351 * @gfp: priority for memory allocation 2352 * 2353 * Note: While this allocator tries to use high order pages, there is 2354 * no guarantee that allocations succeed. Therefore, @sz MUST be 2355 * less or equal than PAGE_SIZE. 2356 */ 2357 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp) 2358 { 2359 if (pfrag->page) { 2360 if (page_ref_count(pfrag->page) == 1) { 2361 pfrag->offset = 0; 2362 return true; 2363 } 2364 if (pfrag->offset + sz <= pfrag->size) 2365 return true; 2366 put_page(pfrag->page); 2367 } 2368 2369 pfrag->offset = 0; 2370 if (SKB_FRAG_PAGE_ORDER && 2371 !static_branch_unlikely(&net_high_order_alloc_disable_key)) { 2372 /* Avoid direct reclaim but allow kswapd to wake */ 2373 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) | 2374 __GFP_COMP | __GFP_NOWARN | 2375 __GFP_NORETRY, 2376 SKB_FRAG_PAGE_ORDER); 2377 if (likely(pfrag->page)) { 2378 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER; 2379 return true; 2380 } 2381 } 2382 pfrag->page = alloc_page(gfp); 2383 if (likely(pfrag->page)) { 2384 pfrag->size = PAGE_SIZE; 2385 return true; 2386 } 2387 return false; 2388 } 2389 EXPORT_SYMBOL(skb_page_frag_refill); 2390 2391 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 2392 { 2393 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 2394 return true; 2395 2396 sk_enter_memory_pressure(sk); 2397 sk_stream_moderate_sndbuf(sk); 2398 return false; 2399 } 2400 EXPORT_SYMBOL(sk_page_frag_refill); 2401 2402 static void __lock_sock(struct sock *sk) 2403 __releases(&sk->sk_lock.slock) 2404 __acquires(&sk->sk_lock.slock) 2405 { 2406 DEFINE_WAIT(wait); 2407 2408 for (;;) { 2409 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 2410 TASK_UNINTERRUPTIBLE); 2411 spin_unlock_bh(&sk->sk_lock.slock); 2412 schedule(); 2413 spin_lock_bh(&sk->sk_lock.slock); 2414 if (!sock_owned_by_user(sk)) 2415 break; 2416 } 2417 finish_wait(&sk->sk_lock.wq, &wait); 2418 } 2419 2420 void __release_sock(struct sock *sk) 2421 __releases(&sk->sk_lock.slock) 2422 __acquires(&sk->sk_lock.slock) 2423 { 2424 struct sk_buff *skb, *next; 2425 2426 while ((skb = sk->sk_backlog.head) != NULL) { 2427 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 2428 2429 spin_unlock_bh(&sk->sk_lock.slock); 2430 2431 do { 2432 next = skb->next; 2433 prefetch(next); 2434 WARN_ON_ONCE(skb_dst_is_noref(skb)); 2435 skb_mark_not_on_list(skb); 2436 sk_backlog_rcv(sk, skb); 2437 2438 cond_resched(); 2439 2440 skb = next; 2441 } while (skb != NULL); 2442 2443 spin_lock_bh(&sk->sk_lock.slock); 2444 } 2445 2446 /* 2447 * Doing the zeroing here guarantee we can not loop forever 2448 * while a wild producer attempts to flood us. 2449 */ 2450 sk->sk_backlog.len = 0; 2451 } 2452 2453 void __sk_flush_backlog(struct sock *sk) 2454 { 2455 spin_lock_bh(&sk->sk_lock.slock); 2456 __release_sock(sk); 2457 spin_unlock_bh(&sk->sk_lock.slock); 2458 } 2459 2460 /** 2461 * sk_wait_data - wait for data to arrive at sk_receive_queue 2462 * @sk: sock to wait on 2463 * @timeo: for how long 2464 * @skb: last skb seen on sk_receive_queue 2465 * 2466 * Now socket state including sk->sk_err is changed only under lock, 2467 * hence we may omit checks after joining wait queue. 2468 * We check receive queue before schedule() only as optimization; 2469 * it is very likely that release_sock() added new data. 2470 */ 2471 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb) 2472 { 2473 DEFINE_WAIT_FUNC(wait, woken_wake_function); 2474 int rc; 2475 2476 add_wait_queue(sk_sleep(sk), &wait); 2477 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); 2478 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait); 2479 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); 2480 remove_wait_queue(sk_sleep(sk), &wait); 2481 return rc; 2482 } 2483 EXPORT_SYMBOL(sk_wait_data); 2484 2485 /** 2486 * __sk_mem_raise_allocated - increase memory_allocated 2487 * @sk: socket 2488 * @size: memory size to allocate 2489 * @amt: pages to allocate 2490 * @kind: allocation type 2491 * 2492 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc 2493 */ 2494 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind) 2495 { 2496 struct proto *prot = sk->sk_prot; 2497 long allocated = sk_memory_allocated_add(sk, amt); 2498 bool charged = true; 2499 2500 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 2501 !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt))) 2502 goto suppress_allocation; 2503 2504 /* Under limit. */ 2505 if (allocated <= sk_prot_mem_limits(sk, 0)) { 2506 sk_leave_memory_pressure(sk); 2507 return 1; 2508 } 2509 2510 /* Under pressure. */ 2511 if (allocated > sk_prot_mem_limits(sk, 1)) 2512 sk_enter_memory_pressure(sk); 2513 2514 /* Over hard limit. */ 2515 if (allocated > sk_prot_mem_limits(sk, 2)) 2516 goto suppress_allocation; 2517 2518 /* guarantee minimum buffer size under pressure */ 2519 if (kind == SK_MEM_RECV) { 2520 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot)) 2521 return 1; 2522 2523 } else { /* SK_MEM_SEND */ 2524 int wmem0 = sk_get_wmem0(sk, prot); 2525 2526 if (sk->sk_type == SOCK_STREAM) { 2527 if (sk->sk_wmem_queued < wmem0) 2528 return 1; 2529 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) { 2530 return 1; 2531 } 2532 } 2533 2534 if (sk_has_memory_pressure(sk)) { 2535 u64 alloc; 2536 2537 if (!sk_under_memory_pressure(sk)) 2538 return 1; 2539 alloc = sk_sockets_allocated_read_positive(sk); 2540 if (sk_prot_mem_limits(sk, 2) > alloc * 2541 sk_mem_pages(sk->sk_wmem_queued + 2542 atomic_read(&sk->sk_rmem_alloc) + 2543 sk->sk_forward_alloc)) 2544 return 1; 2545 } 2546 2547 suppress_allocation: 2548 2549 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2550 sk_stream_moderate_sndbuf(sk); 2551 2552 /* Fail only if socket is _under_ its sndbuf. 2553 * In this case we cannot block, so that we have to fail. 2554 */ 2555 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2556 return 1; 2557 } 2558 2559 if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged)) 2560 trace_sock_exceed_buf_limit(sk, prot, allocated, kind); 2561 2562 sk_memory_allocated_sub(sk, amt); 2563 2564 if (mem_cgroup_sockets_enabled && sk->sk_memcg) 2565 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt); 2566 2567 return 0; 2568 } 2569 EXPORT_SYMBOL(__sk_mem_raise_allocated); 2570 2571 /** 2572 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 2573 * @sk: socket 2574 * @size: memory size to allocate 2575 * @kind: allocation type 2576 * 2577 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 2578 * rmem allocation. This function assumes that protocols which have 2579 * memory_pressure use sk_wmem_queued as write buffer accounting. 2580 */ 2581 int __sk_mem_schedule(struct sock *sk, int size, int kind) 2582 { 2583 int ret, amt = sk_mem_pages(size); 2584 2585 sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT; 2586 ret = __sk_mem_raise_allocated(sk, size, amt, kind); 2587 if (!ret) 2588 sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT; 2589 return ret; 2590 } 2591 EXPORT_SYMBOL(__sk_mem_schedule); 2592 2593 /** 2594 * __sk_mem_reduce_allocated - reclaim memory_allocated 2595 * @sk: socket 2596 * @amount: number of quanta 2597 * 2598 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc 2599 */ 2600 void __sk_mem_reduce_allocated(struct sock *sk, int amount) 2601 { 2602 sk_memory_allocated_sub(sk, amount); 2603 2604 if (mem_cgroup_sockets_enabled && sk->sk_memcg) 2605 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount); 2606 2607 if (sk_under_memory_pressure(sk) && 2608 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2609 sk_leave_memory_pressure(sk); 2610 } 2611 EXPORT_SYMBOL(__sk_mem_reduce_allocated); 2612 2613 /** 2614 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated 2615 * @sk: socket 2616 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple) 2617 */ 2618 void __sk_mem_reclaim(struct sock *sk, int amount) 2619 { 2620 amount >>= SK_MEM_QUANTUM_SHIFT; 2621 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT; 2622 __sk_mem_reduce_allocated(sk, amount); 2623 } 2624 EXPORT_SYMBOL(__sk_mem_reclaim); 2625 2626 int sk_set_peek_off(struct sock *sk, int val) 2627 { 2628 sk->sk_peek_off = val; 2629 return 0; 2630 } 2631 EXPORT_SYMBOL_GPL(sk_set_peek_off); 2632 2633 /* 2634 * Set of default routines for initialising struct proto_ops when 2635 * the protocol does not support a particular function. In certain 2636 * cases where it makes no sense for a protocol to have a "do nothing" 2637 * function, some default processing is provided. 2638 */ 2639 2640 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2641 { 2642 return -EOPNOTSUPP; 2643 } 2644 EXPORT_SYMBOL(sock_no_bind); 2645 2646 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2647 int len, int flags) 2648 { 2649 return -EOPNOTSUPP; 2650 } 2651 EXPORT_SYMBOL(sock_no_connect); 2652 2653 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2654 { 2655 return -EOPNOTSUPP; 2656 } 2657 EXPORT_SYMBOL(sock_no_socketpair); 2658 2659 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags, 2660 bool kern) 2661 { 2662 return -EOPNOTSUPP; 2663 } 2664 EXPORT_SYMBOL(sock_no_accept); 2665 2666 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2667 int peer) 2668 { 2669 return -EOPNOTSUPP; 2670 } 2671 EXPORT_SYMBOL(sock_no_getname); 2672 2673 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2674 { 2675 return -EOPNOTSUPP; 2676 } 2677 EXPORT_SYMBOL(sock_no_ioctl); 2678 2679 int sock_no_listen(struct socket *sock, int backlog) 2680 { 2681 return -EOPNOTSUPP; 2682 } 2683 EXPORT_SYMBOL(sock_no_listen); 2684 2685 int sock_no_shutdown(struct socket *sock, int how) 2686 { 2687 return -EOPNOTSUPP; 2688 } 2689 EXPORT_SYMBOL(sock_no_shutdown); 2690 2691 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2692 char __user *optval, unsigned int optlen) 2693 { 2694 return -EOPNOTSUPP; 2695 } 2696 EXPORT_SYMBOL(sock_no_setsockopt); 2697 2698 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2699 char __user *optval, int __user *optlen) 2700 { 2701 return -EOPNOTSUPP; 2702 } 2703 EXPORT_SYMBOL(sock_no_getsockopt); 2704 2705 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len) 2706 { 2707 return -EOPNOTSUPP; 2708 } 2709 EXPORT_SYMBOL(sock_no_sendmsg); 2710 2711 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len) 2712 { 2713 return -EOPNOTSUPP; 2714 } 2715 EXPORT_SYMBOL(sock_no_sendmsg_locked); 2716 2717 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len, 2718 int flags) 2719 { 2720 return -EOPNOTSUPP; 2721 } 2722 EXPORT_SYMBOL(sock_no_recvmsg); 2723 2724 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2725 { 2726 /* Mirror missing mmap method error code */ 2727 return -ENODEV; 2728 } 2729 EXPORT_SYMBOL(sock_no_mmap); 2730 2731 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2732 { 2733 ssize_t res; 2734 struct msghdr msg = {.msg_flags = flags}; 2735 struct kvec iov; 2736 char *kaddr = kmap(page); 2737 iov.iov_base = kaddr + offset; 2738 iov.iov_len = size; 2739 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2740 kunmap(page); 2741 return res; 2742 } 2743 EXPORT_SYMBOL(sock_no_sendpage); 2744 2745 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page, 2746 int offset, size_t size, int flags) 2747 { 2748 ssize_t res; 2749 struct msghdr msg = {.msg_flags = flags}; 2750 struct kvec iov; 2751 char *kaddr = kmap(page); 2752 2753 iov.iov_base = kaddr + offset; 2754 iov.iov_len = size; 2755 res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size); 2756 kunmap(page); 2757 return res; 2758 } 2759 EXPORT_SYMBOL(sock_no_sendpage_locked); 2760 2761 /* 2762 * Default Socket Callbacks 2763 */ 2764 2765 static void sock_def_wakeup(struct sock *sk) 2766 { 2767 struct socket_wq *wq; 2768 2769 rcu_read_lock(); 2770 wq = rcu_dereference(sk->sk_wq); 2771 if (skwq_has_sleeper(wq)) 2772 wake_up_interruptible_all(&wq->wait); 2773 rcu_read_unlock(); 2774 } 2775 2776 static void sock_def_error_report(struct sock *sk) 2777 { 2778 struct socket_wq *wq; 2779 2780 rcu_read_lock(); 2781 wq = rcu_dereference(sk->sk_wq); 2782 if (skwq_has_sleeper(wq)) 2783 wake_up_interruptible_poll(&wq->wait, EPOLLERR); 2784 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2785 rcu_read_unlock(); 2786 } 2787 2788 static void sock_def_readable(struct sock *sk) 2789 { 2790 struct socket_wq *wq; 2791 2792 rcu_read_lock(); 2793 wq = rcu_dereference(sk->sk_wq); 2794 if (skwq_has_sleeper(wq)) 2795 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI | 2796 EPOLLRDNORM | EPOLLRDBAND); 2797 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2798 rcu_read_unlock(); 2799 } 2800 2801 static void sock_def_write_space(struct sock *sk) 2802 { 2803 struct socket_wq *wq; 2804 2805 rcu_read_lock(); 2806 2807 /* Do not wake up a writer until he can make "significant" 2808 * progress. --DaveM 2809 */ 2810 if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2811 wq = rcu_dereference(sk->sk_wq); 2812 if (skwq_has_sleeper(wq)) 2813 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT | 2814 EPOLLWRNORM | EPOLLWRBAND); 2815 2816 /* Should agree with poll, otherwise some programs break */ 2817 if (sock_writeable(sk)) 2818 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2819 } 2820 2821 rcu_read_unlock(); 2822 } 2823 2824 static void sock_def_destruct(struct sock *sk) 2825 { 2826 } 2827 2828 void sk_send_sigurg(struct sock *sk) 2829 { 2830 if (sk->sk_socket && sk->sk_socket->file) 2831 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2832 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2833 } 2834 EXPORT_SYMBOL(sk_send_sigurg); 2835 2836 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2837 unsigned long expires) 2838 { 2839 if (!mod_timer(timer, expires)) 2840 sock_hold(sk); 2841 } 2842 EXPORT_SYMBOL(sk_reset_timer); 2843 2844 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2845 { 2846 if (del_timer(timer)) 2847 __sock_put(sk); 2848 } 2849 EXPORT_SYMBOL(sk_stop_timer); 2850 2851 void sock_init_data(struct socket *sock, struct sock *sk) 2852 { 2853 sk_init_common(sk); 2854 sk->sk_send_head = NULL; 2855 2856 timer_setup(&sk->sk_timer, NULL, 0); 2857 2858 sk->sk_allocation = GFP_KERNEL; 2859 sk->sk_rcvbuf = sysctl_rmem_default; 2860 sk->sk_sndbuf = sysctl_wmem_default; 2861 sk->sk_state = TCP_CLOSE; 2862 sk_set_socket(sk, sock); 2863 2864 sock_set_flag(sk, SOCK_ZAPPED); 2865 2866 if (sock) { 2867 sk->sk_type = sock->type; 2868 RCU_INIT_POINTER(sk->sk_wq, &sock->wq); 2869 sock->sk = sk; 2870 sk->sk_uid = SOCK_INODE(sock)->i_uid; 2871 } else { 2872 RCU_INIT_POINTER(sk->sk_wq, NULL); 2873 sk->sk_uid = make_kuid(sock_net(sk)->user_ns, 0); 2874 } 2875 2876 rwlock_init(&sk->sk_callback_lock); 2877 if (sk->sk_kern_sock) 2878 lockdep_set_class_and_name( 2879 &sk->sk_callback_lock, 2880 af_kern_callback_keys + sk->sk_family, 2881 af_family_kern_clock_key_strings[sk->sk_family]); 2882 else 2883 lockdep_set_class_and_name( 2884 &sk->sk_callback_lock, 2885 af_callback_keys + sk->sk_family, 2886 af_family_clock_key_strings[sk->sk_family]); 2887 2888 sk->sk_state_change = sock_def_wakeup; 2889 sk->sk_data_ready = sock_def_readable; 2890 sk->sk_write_space = sock_def_write_space; 2891 sk->sk_error_report = sock_def_error_report; 2892 sk->sk_destruct = sock_def_destruct; 2893 2894 sk->sk_frag.page = NULL; 2895 sk->sk_frag.offset = 0; 2896 sk->sk_peek_off = -1; 2897 2898 sk->sk_peer_pid = NULL; 2899 sk->sk_peer_cred = NULL; 2900 sk->sk_write_pending = 0; 2901 sk->sk_rcvlowat = 1; 2902 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2903 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2904 2905 sk->sk_stamp = SK_DEFAULT_STAMP; 2906 #if BITS_PER_LONG==32 2907 seqlock_init(&sk->sk_stamp_seq); 2908 #endif 2909 atomic_set(&sk->sk_zckey, 0); 2910 2911 #ifdef CONFIG_NET_RX_BUSY_POLL 2912 sk->sk_napi_id = 0; 2913 sk->sk_ll_usec = sysctl_net_busy_read; 2914 #endif 2915 2916 sk->sk_max_pacing_rate = ~0UL; 2917 sk->sk_pacing_rate = ~0UL; 2918 sk->sk_pacing_shift = 10; 2919 sk->sk_incoming_cpu = -1; 2920 2921 sk_rx_queue_clear(sk); 2922 /* 2923 * Before updating sk_refcnt, we must commit prior changes to memory 2924 * (Documentation/RCU/rculist_nulls.txt for details) 2925 */ 2926 smp_wmb(); 2927 refcount_set(&sk->sk_refcnt, 1); 2928 atomic_set(&sk->sk_drops, 0); 2929 } 2930 EXPORT_SYMBOL(sock_init_data); 2931 2932 void lock_sock_nested(struct sock *sk, int subclass) 2933 { 2934 might_sleep(); 2935 spin_lock_bh(&sk->sk_lock.slock); 2936 if (sk->sk_lock.owned) 2937 __lock_sock(sk); 2938 sk->sk_lock.owned = 1; 2939 spin_unlock(&sk->sk_lock.slock); 2940 /* 2941 * The sk_lock has mutex_lock() semantics here: 2942 */ 2943 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2944 local_bh_enable(); 2945 } 2946 EXPORT_SYMBOL(lock_sock_nested); 2947 2948 void release_sock(struct sock *sk) 2949 { 2950 spin_lock_bh(&sk->sk_lock.slock); 2951 if (sk->sk_backlog.tail) 2952 __release_sock(sk); 2953 2954 /* Warning : release_cb() might need to release sk ownership, 2955 * ie call sock_release_ownership(sk) before us. 2956 */ 2957 if (sk->sk_prot->release_cb) 2958 sk->sk_prot->release_cb(sk); 2959 2960 sock_release_ownership(sk); 2961 if (waitqueue_active(&sk->sk_lock.wq)) 2962 wake_up(&sk->sk_lock.wq); 2963 spin_unlock_bh(&sk->sk_lock.slock); 2964 } 2965 EXPORT_SYMBOL(release_sock); 2966 2967 /** 2968 * lock_sock_fast - fast version of lock_sock 2969 * @sk: socket 2970 * 2971 * This version should be used for very small section, where process wont block 2972 * return false if fast path is taken: 2973 * 2974 * sk_lock.slock locked, owned = 0, BH disabled 2975 * 2976 * return true if slow path is taken: 2977 * 2978 * sk_lock.slock unlocked, owned = 1, BH enabled 2979 */ 2980 bool lock_sock_fast(struct sock *sk) 2981 { 2982 might_sleep(); 2983 spin_lock_bh(&sk->sk_lock.slock); 2984 2985 if (!sk->sk_lock.owned) 2986 /* 2987 * Note : We must disable BH 2988 */ 2989 return false; 2990 2991 __lock_sock(sk); 2992 sk->sk_lock.owned = 1; 2993 spin_unlock(&sk->sk_lock.slock); 2994 /* 2995 * The sk_lock has mutex_lock() semantics here: 2996 */ 2997 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2998 local_bh_enable(); 2999 return true; 3000 } 3001 EXPORT_SYMBOL(lock_sock_fast); 3002 3003 int sock_gettstamp(struct socket *sock, void __user *userstamp, 3004 bool timeval, bool time32) 3005 { 3006 struct sock *sk = sock->sk; 3007 struct timespec64 ts; 3008 3009 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 3010 ts = ktime_to_timespec64(sock_read_timestamp(sk)); 3011 if (ts.tv_sec == -1) 3012 return -ENOENT; 3013 if (ts.tv_sec == 0) { 3014 ktime_t kt = ktime_get_real(); 3015 sock_write_timestamp(sk, kt);; 3016 ts = ktime_to_timespec64(kt); 3017 } 3018 3019 if (timeval) 3020 ts.tv_nsec /= 1000; 3021 3022 #ifdef CONFIG_COMPAT_32BIT_TIME 3023 if (time32) 3024 return put_old_timespec32(&ts, userstamp); 3025 #endif 3026 #ifdef CONFIG_SPARC64 3027 /* beware of padding in sparc64 timeval */ 3028 if (timeval && !in_compat_syscall()) { 3029 struct __kernel_old_timeval __user tv = { 3030 .tv_sec = ts.tv_sec, 3031 .tv_usec = ts.tv_nsec, 3032 }; 3033 if (copy_to_user(userstamp, &tv, sizeof(tv))) 3034 return -EFAULT; 3035 return 0; 3036 } 3037 #endif 3038 return put_timespec64(&ts, userstamp); 3039 } 3040 EXPORT_SYMBOL(sock_gettstamp); 3041 3042 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag) 3043 { 3044 if (!sock_flag(sk, flag)) { 3045 unsigned long previous_flags = sk->sk_flags; 3046 3047 sock_set_flag(sk, flag); 3048 /* 3049 * we just set one of the two flags which require net 3050 * time stamping, but time stamping might have been on 3051 * already because of the other one 3052 */ 3053 if (sock_needs_netstamp(sk) && 3054 !(previous_flags & SK_FLAGS_TIMESTAMP)) 3055 net_enable_timestamp(); 3056 } 3057 } 3058 3059 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 3060 int level, int type) 3061 { 3062 struct sock_exterr_skb *serr; 3063 struct sk_buff *skb; 3064 int copied, err; 3065 3066 err = -EAGAIN; 3067 skb = sock_dequeue_err_skb(sk); 3068 if (skb == NULL) 3069 goto out; 3070 3071 copied = skb->len; 3072 if (copied > len) { 3073 msg->msg_flags |= MSG_TRUNC; 3074 copied = len; 3075 } 3076 err = skb_copy_datagram_msg(skb, 0, msg, copied); 3077 if (err) 3078 goto out_free_skb; 3079 3080 sock_recv_timestamp(msg, sk, skb); 3081 3082 serr = SKB_EXT_ERR(skb); 3083 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 3084 3085 msg->msg_flags |= MSG_ERRQUEUE; 3086 err = copied; 3087 3088 out_free_skb: 3089 kfree_skb(skb); 3090 out: 3091 return err; 3092 } 3093 EXPORT_SYMBOL(sock_recv_errqueue); 3094 3095 /* 3096 * Get a socket option on an socket. 3097 * 3098 * FIX: POSIX 1003.1g is very ambiguous here. It states that 3099 * asynchronous errors should be reported by getsockopt. We assume 3100 * this means if you specify SO_ERROR (otherwise whats the point of it). 3101 */ 3102 int sock_common_getsockopt(struct socket *sock, int level, int optname, 3103 char __user *optval, int __user *optlen) 3104 { 3105 struct sock *sk = sock->sk; 3106 3107 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 3108 } 3109 EXPORT_SYMBOL(sock_common_getsockopt); 3110 3111 #ifdef CONFIG_COMPAT 3112 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 3113 char __user *optval, int __user *optlen) 3114 { 3115 struct sock *sk = sock->sk; 3116 3117 if (sk->sk_prot->compat_getsockopt != NULL) 3118 return sk->sk_prot->compat_getsockopt(sk, level, optname, 3119 optval, optlen); 3120 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 3121 } 3122 EXPORT_SYMBOL(compat_sock_common_getsockopt); 3123 #endif 3124 3125 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 3126 int flags) 3127 { 3128 struct sock *sk = sock->sk; 3129 int addr_len = 0; 3130 int err; 3131 3132 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, 3133 flags & ~MSG_DONTWAIT, &addr_len); 3134 if (err >= 0) 3135 msg->msg_namelen = addr_len; 3136 return err; 3137 } 3138 EXPORT_SYMBOL(sock_common_recvmsg); 3139 3140 /* 3141 * Set socket options on an inet socket. 3142 */ 3143 int sock_common_setsockopt(struct socket *sock, int level, int optname, 3144 char __user *optval, unsigned int optlen) 3145 { 3146 struct sock *sk = sock->sk; 3147 3148 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 3149 } 3150 EXPORT_SYMBOL(sock_common_setsockopt); 3151 3152 #ifdef CONFIG_COMPAT 3153 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 3154 char __user *optval, unsigned int optlen) 3155 { 3156 struct sock *sk = sock->sk; 3157 3158 if (sk->sk_prot->compat_setsockopt != NULL) 3159 return sk->sk_prot->compat_setsockopt(sk, level, optname, 3160 optval, optlen); 3161 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 3162 } 3163 EXPORT_SYMBOL(compat_sock_common_setsockopt); 3164 #endif 3165 3166 void sk_common_release(struct sock *sk) 3167 { 3168 if (sk->sk_prot->destroy) 3169 sk->sk_prot->destroy(sk); 3170 3171 /* 3172 * Observation: when sock_common_release is called, processes have 3173 * no access to socket. But net still has. 3174 * Step one, detach it from networking: 3175 * 3176 * A. Remove from hash tables. 3177 */ 3178 3179 sk->sk_prot->unhash(sk); 3180 3181 /* 3182 * In this point socket cannot receive new packets, but it is possible 3183 * that some packets are in flight because some CPU runs receiver and 3184 * did hash table lookup before we unhashed socket. They will achieve 3185 * receive queue and will be purged by socket destructor. 3186 * 3187 * Also we still have packets pending on receive queue and probably, 3188 * our own packets waiting in device queues. sock_destroy will drain 3189 * receive queue, but transmitted packets will delay socket destruction 3190 * until the last reference will be released. 3191 */ 3192 3193 sock_orphan(sk); 3194 3195 xfrm_sk_free_policy(sk); 3196 3197 sk_refcnt_debug_release(sk); 3198 3199 sock_put(sk); 3200 } 3201 EXPORT_SYMBOL(sk_common_release); 3202 3203 void sk_get_meminfo(const struct sock *sk, u32 *mem) 3204 { 3205 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS); 3206 3207 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk); 3208 mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf; 3209 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk); 3210 mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf; 3211 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc; 3212 mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued; 3213 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc); 3214 mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len; 3215 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops); 3216 } 3217 3218 #ifdef CONFIG_PROC_FS 3219 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 3220 struct prot_inuse { 3221 int val[PROTO_INUSE_NR]; 3222 }; 3223 3224 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 3225 3226 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 3227 { 3228 __this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val); 3229 } 3230 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 3231 3232 int sock_prot_inuse_get(struct net *net, struct proto *prot) 3233 { 3234 int cpu, idx = prot->inuse_idx; 3235 int res = 0; 3236 3237 for_each_possible_cpu(cpu) 3238 res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx]; 3239 3240 return res >= 0 ? res : 0; 3241 } 3242 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 3243 3244 static void sock_inuse_add(struct net *net, int val) 3245 { 3246 this_cpu_add(*net->core.sock_inuse, val); 3247 } 3248 3249 int sock_inuse_get(struct net *net) 3250 { 3251 int cpu, res = 0; 3252 3253 for_each_possible_cpu(cpu) 3254 res += *per_cpu_ptr(net->core.sock_inuse, cpu); 3255 3256 return res; 3257 } 3258 3259 EXPORT_SYMBOL_GPL(sock_inuse_get); 3260 3261 static int __net_init sock_inuse_init_net(struct net *net) 3262 { 3263 net->core.prot_inuse = alloc_percpu(struct prot_inuse); 3264 if (net->core.prot_inuse == NULL) 3265 return -ENOMEM; 3266 3267 net->core.sock_inuse = alloc_percpu(int); 3268 if (net->core.sock_inuse == NULL) 3269 goto out; 3270 3271 return 0; 3272 3273 out: 3274 free_percpu(net->core.prot_inuse); 3275 return -ENOMEM; 3276 } 3277 3278 static void __net_exit sock_inuse_exit_net(struct net *net) 3279 { 3280 free_percpu(net->core.prot_inuse); 3281 free_percpu(net->core.sock_inuse); 3282 } 3283 3284 static struct pernet_operations net_inuse_ops = { 3285 .init = sock_inuse_init_net, 3286 .exit = sock_inuse_exit_net, 3287 }; 3288 3289 static __init int net_inuse_init(void) 3290 { 3291 if (register_pernet_subsys(&net_inuse_ops)) 3292 panic("Cannot initialize net inuse counters"); 3293 3294 return 0; 3295 } 3296 3297 core_initcall(net_inuse_init); 3298 3299 static int assign_proto_idx(struct proto *prot) 3300 { 3301 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 3302 3303 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 3304 pr_err("PROTO_INUSE_NR exhausted\n"); 3305 return -ENOSPC; 3306 } 3307 3308 set_bit(prot->inuse_idx, proto_inuse_idx); 3309 return 0; 3310 } 3311 3312 static void release_proto_idx(struct proto *prot) 3313 { 3314 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 3315 clear_bit(prot->inuse_idx, proto_inuse_idx); 3316 } 3317 #else 3318 static inline int assign_proto_idx(struct proto *prot) 3319 { 3320 return 0; 3321 } 3322 3323 static inline void release_proto_idx(struct proto *prot) 3324 { 3325 } 3326 3327 static void sock_inuse_add(struct net *net, int val) 3328 { 3329 } 3330 #endif 3331 3332 static void req_prot_cleanup(struct request_sock_ops *rsk_prot) 3333 { 3334 if (!rsk_prot) 3335 return; 3336 kfree(rsk_prot->slab_name); 3337 rsk_prot->slab_name = NULL; 3338 kmem_cache_destroy(rsk_prot->slab); 3339 rsk_prot->slab = NULL; 3340 } 3341 3342 static int req_prot_init(const struct proto *prot) 3343 { 3344 struct request_sock_ops *rsk_prot = prot->rsk_prot; 3345 3346 if (!rsk_prot) 3347 return 0; 3348 3349 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", 3350 prot->name); 3351 if (!rsk_prot->slab_name) 3352 return -ENOMEM; 3353 3354 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name, 3355 rsk_prot->obj_size, 0, 3356 SLAB_ACCOUNT | prot->slab_flags, 3357 NULL); 3358 3359 if (!rsk_prot->slab) { 3360 pr_crit("%s: Can't create request sock SLAB cache!\n", 3361 prot->name); 3362 return -ENOMEM; 3363 } 3364 return 0; 3365 } 3366 3367 int proto_register(struct proto *prot, int alloc_slab) 3368 { 3369 int ret = -ENOBUFS; 3370 3371 if (alloc_slab) { 3372 prot->slab = kmem_cache_create_usercopy(prot->name, 3373 prot->obj_size, 0, 3374 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT | 3375 prot->slab_flags, 3376 prot->useroffset, prot->usersize, 3377 NULL); 3378 3379 if (prot->slab == NULL) { 3380 pr_crit("%s: Can't create sock SLAB cache!\n", 3381 prot->name); 3382 goto out; 3383 } 3384 3385 if (req_prot_init(prot)) 3386 goto out_free_request_sock_slab; 3387 3388 if (prot->twsk_prot != NULL) { 3389 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 3390 3391 if (prot->twsk_prot->twsk_slab_name == NULL) 3392 goto out_free_request_sock_slab; 3393 3394 prot->twsk_prot->twsk_slab = 3395 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 3396 prot->twsk_prot->twsk_obj_size, 3397 0, 3398 SLAB_ACCOUNT | 3399 prot->slab_flags, 3400 NULL); 3401 if (prot->twsk_prot->twsk_slab == NULL) 3402 goto out_free_timewait_sock_slab_name; 3403 } 3404 } 3405 3406 mutex_lock(&proto_list_mutex); 3407 ret = assign_proto_idx(prot); 3408 if (ret) { 3409 mutex_unlock(&proto_list_mutex); 3410 goto out_free_timewait_sock_slab_name; 3411 } 3412 list_add(&prot->node, &proto_list); 3413 mutex_unlock(&proto_list_mutex); 3414 return ret; 3415 3416 out_free_timewait_sock_slab_name: 3417 if (alloc_slab && prot->twsk_prot) 3418 kfree(prot->twsk_prot->twsk_slab_name); 3419 out_free_request_sock_slab: 3420 if (alloc_slab) { 3421 req_prot_cleanup(prot->rsk_prot); 3422 3423 kmem_cache_destroy(prot->slab); 3424 prot->slab = NULL; 3425 } 3426 out: 3427 return ret; 3428 } 3429 EXPORT_SYMBOL(proto_register); 3430 3431 void proto_unregister(struct proto *prot) 3432 { 3433 mutex_lock(&proto_list_mutex); 3434 release_proto_idx(prot); 3435 list_del(&prot->node); 3436 mutex_unlock(&proto_list_mutex); 3437 3438 kmem_cache_destroy(prot->slab); 3439 prot->slab = NULL; 3440 3441 req_prot_cleanup(prot->rsk_prot); 3442 3443 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 3444 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 3445 kfree(prot->twsk_prot->twsk_slab_name); 3446 prot->twsk_prot->twsk_slab = NULL; 3447 } 3448 } 3449 EXPORT_SYMBOL(proto_unregister); 3450 3451 int sock_load_diag_module(int family, int protocol) 3452 { 3453 if (!protocol) { 3454 if (!sock_is_registered(family)) 3455 return -ENOENT; 3456 3457 return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK, 3458 NETLINK_SOCK_DIAG, family); 3459 } 3460 3461 #ifdef CONFIG_INET 3462 if (family == AF_INET && 3463 protocol != IPPROTO_RAW && 3464 !rcu_access_pointer(inet_protos[protocol])) 3465 return -ENOENT; 3466 #endif 3467 3468 return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK, 3469 NETLINK_SOCK_DIAG, family, protocol); 3470 } 3471 EXPORT_SYMBOL(sock_load_diag_module); 3472 3473 #ifdef CONFIG_PROC_FS 3474 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 3475 __acquires(proto_list_mutex) 3476 { 3477 mutex_lock(&proto_list_mutex); 3478 return seq_list_start_head(&proto_list, *pos); 3479 } 3480 3481 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 3482 { 3483 return seq_list_next(v, &proto_list, pos); 3484 } 3485 3486 static void proto_seq_stop(struct seq_file *seq, void *v) 3487 __releases(proto_list_mutex) 3488 { 3489 mutex_unlock(&proto_list_mutex); 3490 } 3491 3492 static char proto_method_implemented(const void *method) 3493 { 3494 return method == NULL ? 'n' : 'y'; 3495 } 3496 static long sock_prot_memory_allocated(struct proto *proto) 3497 { 3498 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 3499 } 3500 3501 static const char *sock_prot_memory_pressure(struct proto *proto) 3502 { 3503 return proto->memory_pressure != NULL ? 3504 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 3505 } 3506 3507 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 3508 { 3509 3510 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 3511 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 3512 proto->name, 3513 proto->obj_size, 3514 sock_prot_inuse_get(seq_file_net(seq), proto), 3515 sock_prot_memory_allocated(proto), 3516 sock_prot_memory_pressure(proto), 3517 proto->max_header, 3518 proto->slab == NULL ? "no" : "yes", 3519 module_name(proto->owner), 3520 proto_method_implemented(proto->close), 3521 proto_method_implemented(proto->connect), 3522 proto_method_implemented(proto->disconnect), 3523 proto_method_implemented(proto->accept), 3524 proto_method_implemented(proto->ioctl), 3525 proto_method_implemented(proto->init), 3526 proto_method_implemented(proto->destroy), 3527 proto_method_implemented(proto->shutdown), 3528 proto_method_implemented(proto->setsockopt), 3529 proto_method_implemented(proto->getsockopt), 3530 proto_method_implemented(proto->sendmsg), 3531 proto_method_implemented(proto->recvmsg), 3532 proto_method_implemented(proto->sendpage), 3533 proto_method_implemented(proto->bind), 3534 proto_method_implemented(proto->backlog_rcv), 3535 proto_method_implemented(proto->hash), 3536 proto_method_implemented(proto->unhash), 3537 proto_method_implemented(proto->get_port), 3538 proto_method_implemented(proto->enter_memory_pressure)); 3539 } 3540 3541 static int proto_seq_show(struct seq_file *seq, void *v) 3542 { 3543 if (v == &proto_list) 3544 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 3545 "protocol", 3546 "size", 3547 "sockets", 3548 "memory", 3549 "press", 3550 "maxhdr", 3551 "slab", 3552 "module", 3553 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 3554 else 3555 proto_seq_printf(seq, list_entry(v, struct proto, node)); 3556 return 0; 3557 } 3558 3559 static const struct seq_operations proto_seq_ops = { 3560 .start = proto_seq_start, 3561 .next = proto_seq_next, 3562 .stop = proto_seq_stop, 3563 .show = proto_seq_show, 3564 }; 3565 3566 static __net_init int proto_init_net(struct net *net) 3567 { 3568 if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops, 3569 sizeof(struct seq_net_private))) 3570 return -ENOMEM; 3571 3572 return 0; 3573 } 3574 3575 static __net_exit void proto_exit_net(struct net *net) 3576 { 3577 remove_proc_entry("protocols", net->proc_net); 3578 } 3579 3580 3581 static __net_initdata struct pernet_operations proto_net_ops = { 3582 .init = proto_init_net, 3583 .exit = proto_exit_net, 3584 }; 3585 3586 static int __init proto_init(void) 3587 { 3588 return register_pernet_subsys(&proto_net_ops); 3589 } 3590 3591 subsys_initcall(proto_init); 3592 3593 #endif /* PROC_FS */ 3594 3595 #ifdef CONFIG_NET_RX_BUSY_POLL 3596 bool sk_busy_loop_end(void *p, unsigned long start_time) 3597 { 3598 struct sock *sk = p; 3599 3600 return !skb_queue_empty(&sk->sk_receive_queue) || 3601 sk_busy_loop_timeout(sk, start_time); 3602 } 3603 EXPORT_SYMBOL(sk_busy_loop_end); 3604 #endif /* CONFIG_NET_RX_BUSY_POLL */ 3605