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; 336 337 if (timeo == MAX_SCHEDULE_TIMEOUT) { 338 tv.tv_sec = 0; 339 tv.tv_usec = 0; 340 } else { 341 tv.tv_sec = timeo / HZ; 342 tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ; 343 } 344 345 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) { 346 struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec }; 347 *(struct old_timeval32 *)optval = tv32; 348 return sizeof(tv32); 349 } 350 351 if (old_timeval) { 352 struct __kernel_old_timeval old_tv; 353 old_tv.tv_sec = tv.tv_sec; 354 old_tv.tv_usec = tv.tv_usec; 355 *(struct __kernel_old_timeval *)optval = old_tv; 356 return sizeof(old_tv); 357 } 358 359 *(struct __kernel_sock_timeval *)optval = tv; 360 return sizeof(tv); 361 } 362 363 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen, bool old_timeval) 364 { 365 struct __kernel_sock_timeval tv; 366 367 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) { 368 struct old_timeval32 tv32; 369 370 if (optlen < sizeof(tv32)) 371 return -EINVAL; 372 373 if (copy_from_user(&tv32, optval, sizeof(tv32))) 374 return -EFAULT; 375 tv.tv_sec = tv32.tv_sec; 376 tv.tv_usec = tv32.tv_usec; 377 } else if (old_timeval) { 378 struct __kernel_old_timeval old_tv; 379 380 if (optlen < sizeof(old_tv)) 381 return -EINVAL; 382 if (copy_from_user(&old_tv, optval, sizeof(old_tv))) 383 return -EFAULT; 384 tv.tv_sec = old_tv.tv_sec; 385 tv.tv_usec = old_tv.tv_usec; 386 } else { 387 if (optlen < sizeof(tv)) 388 return -EINVAL; 389 if (copy_from_user(&tv, optval, sizeof(tv))) 390 return -EFAULT; 391 } 392 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 393 return -EDOM; 394 395 if (tv.tv_sec < 0) { 396 static int warned __read_mostly; 397 398 *timeo_p = 0; 399 if (warned < 10 && net_ratelimit()) { 400 warned++; 401 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 402 __func__, current->comm, task_pid_nr(current)); 403 } 404 return 0; 405 } 406 *timeo_p = MAX_SCHEDULE_TIMEOUT; 407 if (tv.tv_sec == 0 && tv.tv_usec == 0) 408 return 0; 409 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)) 410 *timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ); 411 return 0; 412 } 413 414 static void sock_warn_obsolete_bsdism(const char *name) 415 { 416 static int warned; 417 static char warncomm[TASK_COMM_LEN]; 418 if (strcmp(warncomm, current->comm) && warned < 5) { 419 strcpy(warncomm, current->comm); 420 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", 421 warncomm, name); 422 warned++; 423 } 424 } 425 426 static bool sock_needs_netstamp(const struct sock *sk) 427 { 428 switch (sk->sk_family) { 429 case AF_UNSPEC: 430 case AF_UNIX: 431 return false; 432 default: 433 return true; 434 } 435 } 436 437 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 438 { 439 if (sk->sk_flags & flags) { 440 sk->sk_flags &= ~flags; 441 if (sock_needs_netstamp(sk) && 442 !(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 443 net_disable_timestamp(); 444 } 445 } 446 447 448 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 449 { 450 unsigned long flags; 451 struct sk_buff_head *list = &sk->sk_receive_queue; 452 453 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 454 atomic_inc(&sk->sk_drops); 455 trace_sock_rcvqueue_full(sk, skb); 456 return -ENOMEM; 457 } 458 459 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 460 atomic_inc(&sk->sk_drops); 461 return -ENOBUFS; 462 } 463 464 skb->dev = NULL; 465 skb_set_owner_r(skb, sk); 466 467 /* we escape from rcu protected region, make sure we dont leak 468 * a norefcounted dst 469 */ 470 skb_dst_force(skb); 471 472 spin_lock_irqsave(&list->lock, flags); 473 sock_skb_set_dropcount(sk, skb); 474 __skb_queue_tail(list, skb); 475 spin_unlock_irqrestore(&list->lock, flags); 476 477 if (!sock_flag(sk, SOCK_DEAD)) 478 sk->sk_data_ready(sk); 479 return 0; 480 } 481 EXPORT_SYMBOL(__sock_queue_rcv_skb); 482 483 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 484 { 485 int err; 486 487 err = sk_filter(sk, skb); 488 if (err) 489 return err; 490 491 return __sock_queue_rcv_skb(sk, skb); 492 } 493 EXPORT_SYMBOL(sock_queue_rcv_skb); 494 495 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, 496 const int nested, unsigned int trim_cap, bool refcounted) 497 { 498 int rc = NET_RX_SUCCESS; 499 500 if (sk_filter_trim_cap(sk, skb, trim_cap)) 501 goto discard_and_relse; 502 503 skb->dev = NULL; 504 505 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 506 atomic_inc(&sk->sk_drops); 507 goto discard_and_relse; 508 } 509 if (nested) 510 bh_lock_sock_nested(sk); 511 else 512 bh_lock_sock(sk); 513 if (!sock_owned_by_user(sk)) { 514 /* 515 * trylock + unlock semantics: 516 */ 517 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 518 519 rc = sk_backlog_rcv(sk, skb); 520 521 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 522 } else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) { 523 bh_unlock_sock(sk); 524 atomic_inc(&sk->sk_drops); 525 goto discard_and_relse; 526 } 527 528 bh_unlock_sock(sk); 529 out: 530 if (refcounted) 531 sock_put(sk); 532 return rc; 533 discard_and_relse: 534 kfree_skb(skb); 535 goto out; 536 } 537 EXPORT_SYMBOL(__sk_receive_skb); 538 539 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 540 { 541 struct dst_entry *dst = __sk_dst_get(sk); 542 543 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 544 sk_tx_queue_clear(sk); 545 sk->sk_dst_pending_confirm = 0; 546 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 547 dst_release(dst); 548 return NULL; 549 } 550 551 return dst; 552 } 553 EXPORT_SYMBOL(__sk_dst_check); 554 555 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 556 { 557 struct dst_entry *dst = sk_dst_get(sk); 558 559 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 560 sk_dst_reset(sk); 561 dst_release(dst); 562 return NULL; 563 } 564 565 return dst; 566 } 567 EXPORT_SYMBOL(sk_dst_check); 568 569 static int sock_bindtoindex_locked(struct sock *sk, int ifindex) 570 { 571 int ret = -ENOPROTOOPT; 572 #ifdef CONFIG_NETDEVICES 573 struct net *net = sock_net(sk); 574 575 /* Sorry... */ 576 ret = -EPERM; 577 if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW)) 578 goto out; 579 580 ret = -EINVAL; 581 if (ifindex < 0) 582 goto out; 583 584 sk->sk_bound_dev_if = ifindex; 585 if (sk->sk_prot->rehash) 586 sk->sk_prot->rehash(sk); 587 sk_dst_reset(sk); 588 589 ret = 0; 590 591 out: 592 #endif 593 594 return ret; 595 } 596 597 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk) 598 { 599 int ret; 600 601 if (lock_sk) 602 lock_sock(sk); 603 ret = sock_bindtoindex_locked(sk, ifindex); 604 if (lock_sk) 605 release_sock(sk); 606 607 return ret; 608 } 609 EXPORT_SYMBOL(sock_bindtoindex); 610 611 static int sock_setbindtodevice(struct sock *sk, char __user *optval, 612 int optlen) 613 { 614 int ret = -ENOPROTOOPT; 615 #ifdef CONFIG_NETDEVICES 616 struct net *net = sock_net(sk); 617 char devname[IFNAMSIZ]; 618 int index; 619 620 ret = -EINVAL; 621 if (optlen < 0) 622 goto out; 623 624 /* Bind this socket to a particular device like "eth0", 625 * as specified in the passed interface name. If the 626 * name is "" or the option length is zero the socket 627 * is not bound. 628 */ 629 if (optlen > IFNAMSIZ - 1) 630 optlen = IFNAMSIZ - 1; 631 memset(devname, 0, sizeof(devname)); 632 633 ret = -EFAULT; 634 if (copy_from_user(devname, optval, optlen)) 635 goto out; 636 637 index = 0; 638 if (devname[0] != '\0') { 639 struct net_device *dev; 640 641 rcu_read_lock(); 642 dev = dev_get_by_name_rcu(net, devname); 643 if (dev) 644 index = dev->ifindex; 645 rcu_read_unlock(); 646 ret = -ENODEV; 647 if (!dev) 648 goto out; 649 } 650 651 return sock_bindtoindex(sk, index, true); 652 out: 653 #endif 654 655 return ret; 656 } 657 658 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 659 int __user *optlen, int len) 660 { 661 int ret = -ENOPROTOOPT; 662 #ifdef CONFIG_NETDEVICES 663 struct net *net = sock_net(sk); 664 char devname[IFNAMSIZ]; 665 666 if (sk->sk_bound_dev_if == 0) { 667 len = 0; 668 goto zero; 669 } 670 671 ret = -EINVAL; 672 if (len < IFNAMSIZ) 673 goto out; 674 675 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); 676 if (ret) 677 goto out; 678 679 len = strlen(devname) + 1; 680 681 ret = -EFAULT; 682 if (copy_to_user(optval, devname, len)) 683 goto out; 684 685 zero: 686 ret = -EFAULT; 687 if (put_user(len, optlen)) 688 goto out; 689 690 ret = 0; 691 692 out: 693 #endif 694 695 return ret; 696 } 697 698 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit, 699 int valbool) 700 { 701 if (valbool) 702 sock_set_flag(sk, bit); 703 else 704 sock_reset_flag(sk, bit); 705 } 706 707 bool sk_mc_loop(struct sock *sk) 708 { 709 if (dev_recursion_level()) 710 return false; 711 if (!sk) 712 return true; 713 switch (sk->sk_family) { 714 case AF_INET: 715 return inet_sk(sk)->mc_loop; 716 #if IS_ENABLED(CONFIG_IPV6) 717 case AF_INET6: 718 return inet6_sk(sk)->mc_loop; 719 #endif 720 } 721 WARN_ON_ONCE(1); 722 return true; 723 } 724 EXPORT_SYMBOL(sk_mc_loop); 725 726 void sock_set_reuseaddr(struct sock *sk) 727 { 728 lock_sock(sk); 729 sk->sk_reuse = SK_CAN_REUSE; 730 release_sock(sk); 731 } 732 EXPORT_SYMBOL(sock_set_reuseaddr); 733 734 void sock_set_reuseport(struct sock *sk) 735 { 736 lock_sock(sk); 737 sk->sk_reuseport = true; 738 release_sock(sk); 739 } 740 EXPORT_SYMBOL(sock_set_reuseport); 741 742 void sock_no_linger(struct sock *sk) 743 { 744 lock_sock(sk); 745 sk->sk_lingertime = 0; 746 sock_set_flag(sk, SOCK_LINGER); 747 release_sock(sk); 748 } 749 EXPORT_SYMBOL(sock_no_linger); 750 751 void sock_set_priority(struct sock *sk, u32 priority) 752 { 753 lock_sock(sk); 754 sk->sk_priority = priority; 755 release_sock(sk); 756 } 757 EXPORT_SYMBOL(sock_set_priority); 758 759 void sock_set_sndtimeo(struct sock *sk, s64 secs) 760 { 761 lock_sock(sk); 762 if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1) 763 sk->sk_sndtimeo = secs * HZ; 764 else 765 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 766 release_sock(sk); 767 } 768 EXPORT_SYMBOL(sock_set_sndtimeo); 769 770 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns) 771 { 772 if (val) { 773 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new); 774 sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns); 775 sock_set_flag(sk, SOCK_RCVTSTAMP); 776 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 777 } else { 778 sock_reset_flag(sk, SOCK_RCVTSTAMP); 779 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 780 sock_reset_flag(sk, SOCK_TSTAMP_NEW); 781 } 782 } 783 784 void sock_enable_timestamps(struct sock *sk) 785 { 786 lock_sock(sk); 787 __sock_set_timestamps(sk, true, false, true); 788 release_sock(sk); 789 } 790 EXPORT_SYMBOL(sock_enable_timestamps); 791 792 void sock_set_keepalive(struct sock *sk) 793 { 794 lock_sock(sk); 795 if (sk->sk_prot->keepalive) 796 sk->sk_prot->keepalive(sk, true); 797 sock_valbool_flag(sk, SOCK_KEEPOPEN, true); 798 release_sock(sk); 799 } 800 EXPORT_SYMBOL(sock_set_keepalive); 801 802 static void __sock_set_rcvbuf(struct sock *sk, int val) 803 { 804 /* Ensure val * 2 fits into an int, to prevent max_t() from treating it 805 * as a negative value. 806 */ 807 val = min_t(int, val, INT_MAX / 2); 808 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 809 810 /* We double it on the way in to account for "struct sk_buff" etc. 811 * overhead. Applications assume that the SO_RCVBUF setting they make 812 * will allow that much actual data to be received on that socket. 813 * 814 * Applications are unaware that "struct sk_buff" and other overheads 815 * allocate from the receive buffer during socket buffer allocation. 816 * 817 * And after considering the possible alternatives, returning the value 818 * we actually used in getsockopt is the most desirable behavior. 819 */ 820 WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF)); 821 } 822 823 void sock_set_rcvbuf(struct sock *sk, int val) 824 { 825 lock_sock(sk); 826 __sock_set_rcvbuf(sk, val); 827 release_sock(sk); 828 } 829 EXPORT_SYMBOL(sock_set_rcvbuf); 830 831 /* 832 * This is meant for all protocols to use and covers goings on 833 * at the socket level. Everything here is generic. 834 */ 835 836 int sock_setsockopt(struct socket *sock, int level, int optname, 837 char __user *optval, unsigned int optlen) 838 { 839 struct sock_txtime sk_txtime; 840 struct sock *sk = sock->sk; 841 int val; 842 int valbool; 843 struct linger ling; 844 int ret = 0; 845 846 /* 847 * Options without arguments 848 */ 849 850 if (optname == SO_BINDTODEVICE) 851 return sock_setbindtodevice(sk, optval, optlen); 852 853 if (optlen < sizeof(int)) 854 return -EINVAL; 855 856 if (get_user(val, (int __user *)optval)) 857 return -EFAULT; 858 859 valbool = val ? 1 : 0; 860 861 lock_sock(sk); 862 863 switch (optname) { 864 case SO_DEBUG: 865 if (val && !capable(CAP_NET_ADMIN)) 866 ret = -EACCES; 867 else 868 sock_valbool_flag(sk, SOCK_DBG, valbool); 869 break; 870 case SO_REUSEADDR: 871 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 872 break; 873 case SO_REUSEPORT: 874 sk->sk_reuseport = valbool; 875 break; 876 case SO_TYPE: 877 case SO_PROTOCOL: 878 case SO_DOMAIN: 879 case SO_ERROR: 880 ret = -ENOPROTOOPT; 881 break; 882 case SO_DONTROUTE: 883 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 884 sk_dst_reset(sk); 885 break; 886 case SO_BROADCAST: 887 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 888 break; 889 case SO_SNDBUF: 890 /* Don't error on this BSD doesn't and if you think 891 * about it this is right. Otherwise apps have to 892 * play 'guess the biggest size' games. RCVBUF/SNDBUF 893 * are treated in BSD as hints 894 */ 895 val = min_t(u32, val, sysctl_wmem_max); 896 set_sndbuf: 897 /* Ensure val * 2 fits into an int, to prevent max_t() 898 * from treating it as a negative value. 899 */ 900 val = min_t(int, val, INT_MAX / 2); 901 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 902 WRITE_ONCE(sk->sk_sndbuf, 903 max_t(int, val * 2, SOCK_MIN_SNDBUF)); 904 /* Wake up sending tasks if we upped the value. */ 905 sk->sk_write_space(sk); 906 break; 907 908 case SO_SNDBUFFORCE: 909 if (!capable(CAP_NET_ADMIN)) { 910 ret = -EPERM; 911 break; 912 } 913 914 /* No negative values (to prevent underflow, as val will be 915 * multiplied by 2). 916 */ 917 if (val < 0) 918 val = 0; 919 goto set_sndbuf; 920 921 case SO_RCVBUF: 922 /* Don't error on this BSD doesn't and if you think 923 * about it this is right. Otherwise apps have to 924 * play 'guess the biggest size' games. RCVBUF/SNDBUF 925 * are treated in BSD as hints 926 */ 927 __sock_set_rcvbuf(sk, min_t(u32, val, sysctl_rmem_max)); 928 break; 929 930 case SO_RCVBUFFORCE: 931 if (!capable(CAP_NET_ADMIN)) { 932 ret = -EPERM; 933 break; 934 } 935 936 /* No negative values (to prevent underflow, as val will be 937 * multiplied by 2). 938 */ 939 __sock_set_rcvbuf(sk, max(val, 0)); 940 break; 941 942 case SO_KEEPALIVE: 943 if (sk->sk_prot->keepalive) 944 sk->sk_prot->keepalive(sk, valbool); 945 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 946 break; 947 948 case SO_OOBINLINE: 949 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 950 break; 951 952 case SO_NO_CHECK: 953 sk->sk_no_check_tx = valbool; 954 break; 955 956 case SO_PRIORITY: 957 if ((val >= 0 && val <= 6) || 958 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 959 sk->sk_priority = val; 960 else 961 ret = -EPERM; 962 break; 963 964 case SO_LINGER: 965 if (optlen < sizeof(ling)) { 966 ret = -EINVAL; /* 1003.1g */ 967 break; 968 } 969 if (copy_from_user(&ling, optval, sizeof(ling))) { 970 ret = -EFAULT; 971 break; 972 } 973 if (!ling.l_onoff) 974 sock_reset_flag(sk, SOCK_LINGER); 975 else { 976 #if (BITS_PER_LONG == 32) 977 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 978 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 979 else 980 #endif 981 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 982 sock_set_flag(sk, SOCK_LINGER); 983 } 984 break; 985 986 case SO_BSDCOMPAT: 987 sock_warn_obsolete_bsdism("setsockopt"); 988 break; 989 990 case SO_PASSCRED: 991 if (valbool) 992 set_bit(SOCK_PASSCRED, &sock->flags); 993 else 994 clear_bit(SOCK_PASSCRED, &sock->flags); 995 break; 996 997 case SO_TIMESTAMP_OLD: 998 __sock_set_timestamps(sk, valbool, false, false); 999 break; 1000 case SO_TIMESTAMP_NEW: 1001 __sock_set_timestamps(sk, valbool, true, false); 1002 break; 1003 case SO_TIMESTAMPNS_OLD: 1004 __sock_set_timestamps(sk, valbool, false, true); 1005 break; 1006 case SO_TIMESTAMPNS_NEW: 1007 __sock_set_timestamps(sk, valbool, true, true); 1008 break; 1009 case SO_TIMESTAMPING_NEW: 1010 sock_set_flag(sk, SOCK_TSTAMP_NEW); 1011 /* fall through */ 1012 case SO_TIMESTAMPING_OLD: 1013 if (val & ~SOF_TIMESTAMPING_MASK) { 1014 ret = -EINVAL; 1015 break; 1016 } 1017 1018 if (val & SOF_TIMESTAMPING_OPT_ID && 1019 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { 1020 if (sk->sk_protocol == IPPROTO_TCP && 1021 sk->sk_type == SOCK_STREAM) { 1022 if ((1 << sk->sk_state) & 1023 (TCPF_CLOSE | TCPF_LISTEN)) { 1024 ret = -EINVAL; 1025 break; 1026 } 1027 sk->sk_tskey = tcp_sk(sk)->snd_una; 1028 } else { 1029 sk->sk_tskey = 0; 1030 } 1031 } 1032 1033 if (val & SOF_TIMESTAMPING_OPT_STATS && 1034 !(val & SOF_TIMESTAMPING_OPT_TSONLY)) { 1035 ret = -EINVAL; 1036 break; 1037 } 1038 1039 sk->sk_tsflags = val; 1040 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 1041 sock_enable_timestamp(sk, 1042 SOCK_TIMESTAMPING_RX_SOFTWARE); 1043 else { 1044 if (optname == SO_TIMESTAMPING_NEW) 1045 sock_reset_flag(sk, SOCK_TSTAMP_NEW); 1046 1047 sock_disable_timestamp(sk, 1048 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 1049 } 1050 break; 1051 1052 case SO_RCVLOWAT: 1053 if (val < 0) 1054 val = INT_MAX; 1055 if (sock->ops->set_rcvlowat) 1056 ret = sock->ops->set_rcvlowat(sk, val); 1057 else 1058 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1); 1059 break; 1060 1061 case SO_RCVTIMEO_OLD: 1062 case SO_RCVTIMEO_NEW: 1063 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen, optname == SO_RCVTIMEO_OLD); 1064 break; 1065 1066 case SO_SNDTIMEO_OLD: 1067 case SO_SNDTIMEO_NEW: 1068 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen, optname == SO_SNDTIMEO_OLD); 1069 break; 1070 1071 case SO_ATTACH_FILTER: 1072 ret = -EINVAL; 1073 if (optlen == sizeof(struct sock_fprog)) { 1074 struct sock_fprog fprog; 1075 1076 ret = -EFAULT; 1077 if (copy_from_user(&fprog, optval, sizeof(fprog))) 1078 break; 1079 1080 ret = sk_attach_filter(&fprog, sk); 1081 } 1082 break; 1083 1084 case SO_ATTACH_BPF: 1085 ret = -EINVAL; 1086 if (optlen == sizeof(u32)) { 1087 u32 ufd; 1088 1089 ret = -EFAULT; 1090 if (copy_from_user(&ufd, optval, sizeof(ufd))) 1091 break; 1092 1093 ret = sk_attach_bpf(ufd, sk); 1094 } 1095 break; 1096 1097 case SO_ATTACH_REUSEPORT_CBPF: 1098 ret = -EINVAL; 1099 if (optlen == sizeof(struct sock_fprog)) { 1100 struct sock_fprog fprog; 1101 1102 ret = -EFAULT; 1103 if (copy_from_user(&fprog, optval, sizeof(fprog))) 1104 break; 1105 1106 ret = sk_reuseport_attach_filter(&fprog, sk); 1107 } 1108 break; 1109 1110 case SO_ATTACH_REUSEPORT_EBPF: 1111 ret = -EINVAL; 1112 if (optlen == sizeof(u32)) { 1113 u32 ufd; 1114 1115 ret = -EFAULT; 1116 if (copy_from_user(&ufd, optval, sizeof(ufd))) 1117 break; 1118 1119 ret = sk_reuseport_attach_bpf(ufd, sk); 1120 } 1121 break; 1122 1123 case SO_DETACH_REUSEPORT_BPF: 1124 ret = reuseport_detach_prog(sk); 1125 break; 1126 1127 case SO_DETACH_FILTER: 1128 ret = sk_detach_filter(sk); 1129 break; 1130 1131 case SO_LOCK_FILTER: 1132 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 1133 ret = -EPERM; 1134 else 1135 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 1136 break; 1137 1138 case SO_PASSSEC: 1139 if (valbool) 1140 set_bit(SOCK_PASSSEC, &sock->flags); 1141 else 1142 clear_bit(SOCK_PASSSEC, &sock->flags); 1143 break; 1144 case SO_MARK: 1145 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1146 ret = -EPERM; 1147 } else if (val != sk->sk_mark) { 1148 sk->sk_mark = val; 1149 sk_dst_reset(sk); 1150 } 1151 break; 1152 1153 case SO_RXQ_OVFL: 1154 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 1155 break; 1156 1157 case SO_WIFI_STATUS: 1158 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 1159 break; 1160 1161 case SO_PEEK_OFF: 1162 if (sock->ops->set_peek_off) 1163 ret = sock->ops->set_peek_off(sk, val); 1164 else 1165 ret = -EOPNOTSUPP; 1166 break; 1167 1168 case SO_NOFCS: 1169 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 1170 break; 1171 1172 case SO_SELECT_ERR_QUEUE: 1173 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 1174 break; 1175 1176 #ifdef CONFIG_NET_RX_BUSY_POLL 1177 case SO_BUSY_POLL: 1178 /* allow unprivileged users to decrease the value */ 1179 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN)) 1180 ret = -EPERM; 1181 else { 1182 if (val < 0) 1183 ret = -EINVAL; 1184 else 1185 sk->sk_ll_usec = val; 1186 } 1187 break; 1188 #endif 1189 1190 case SO_MAX_PACING_RATE: 1191 { 1192 unsigned long ulval = (val == ~0U) ? ~0UL : val; 1193 1194 if (sizeof(ulval) != sizeof(val) && 1195 optlen >= sizeof(ulval) && 1196 get_user(ulval, (unsigned long __user *)optval)) { 1197 ret = -EFAULT; 1198 break; 1199 } 1200 if (ulval != ~0UL) 1201 cmpxchg(&sk->sk_pacing_status, 1202 SK_PACING_NONE, 1203 SK_PACING_NEEDED); 1204 sk->sk_max_pacing_rate = ulval; 1205 sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval); 1206 break; 1207 } 1208 case SO_INCOMING_CPU: 1209 WRITE_ONCE(sk->sk_incoming_cpu, val); 1210 break; 1211 1212 case SO_CNX_ADVICE: 1213 if (val == 1) 1214 dst_negative_advice(sk); 1215 break; 1216 1217 case SO_ZEROCOPY: 1218 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) { 1219 if (!((sk->sk_type == SOCK_STREAM && 1220 sk->sk_protocol == IPPROTO_TCP) || 1221 (sk->sk_type == SOCK_DGRAM && 1222 sk->sk_protocol == IPPROTO_UDP))) 1223 ret = -ENOTSUPP; 1224 } else if (sk->sk_family != PF_RDS) { 1225 ret = -ENOTSUPP; 1226 } 1227 if (!ret) { 1228 if (val < 0 || val > 1) 1229 ret = -EINVAL; 1230 else 1231 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool); 1232 } 1233 break; 1234 1235 case SO_TXTIME: 1236 if (optlen != sizeof(struct sock_txtime)) { 1237 ret = -EINVAL; 1238 break; 1239 } else if (copy_from_user(&sk_txtime, optval, 1240 sizeof(struct sock_txtime))) { 1241 ret = -EFAULT; 1242 break; 1243 } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) { 1244 ret = -EINVAL; 1245 break; 1246 } 1247 /* CLOCK_MONOTONIC is only used by sch_fq, and this packet 1248 * scheduler has enough safe guards. 1249 */ 1250 if (sk_txtime.clockid != CLOCK_MONOTONIC && 1251 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) { 1252 ret = -EPERM; 1253 break; 1254 } 1255 sock_valbool_flag(sk, SOCK_TXTIME, true); 1256 sk->sk_clockid = sk_txtime.clockid; 1257 sk->sk_txtime_deadline_mode = 1258 !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE); 1259 sk->sk_txtime_report_errors = 1260 !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS); 1261 break; 1262 1263 case SO_BINDTOIFINDEX: 1264 ret = sock_bindtoindex_locked(sk, val); 1265 break; 1266 1267 default: 1268 ret = -ENOPROTOOPT; 1269 break; 1270 } 1271 release_sock(sk); 1272 return ret; 1273 } 1274 EXPORT_SYMBOL(sock_setsockopt); 1275 1276 1277 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 1278 struct ucred *ucred) 1279 { 1280 ucred->pid = pid_vnr(pid); 1281 ucred->uid = ucred->gid = -1; 1282 if (cred) { 1283 struct user_namespace *current_ns = current_user_ns(); 1284 1285 ucred->uid = from_kuid_munged(current_ns, cred->euid); 1286 ucred->gid = from_kgid_munged(current_ns, cred->egid); 1287 } 1288 } 1289 1290 static int groups_to_user(gid_t __user *dst, const struct group_info *src) 1291 { 1292 struct user_namespace *user_ns = current_user_ns(); 1293 int i; 1294 1295 for (i = 0; i < src->ngroups; i++) 1296 if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i)) 1297 return -EFAULT; 1298 1299 return 0; 1300 } 1301 1302 int sock_getsockopt(struct socket *sock, int level, int optname, 1303 char __user *optval, int __user *optlen) 1304 { 1305 struct sock *sk = sock->sk; 1306 1307 union { 1308 int val; 1309 u64 val64; 1310 unsigned long ulval; 1311 struct linger ling; 1312 struct old_timeval32 tm32; 1313 struct __kernel_old_timeval tm; 1314 struct __kernel_sock_timeval stm; 1315 struct sock_txtime txtime; 1316 } v; 1317 1318 int lv = sizeof(int); 1319 int len; 1320 1321 if (get_user(len, optlen)) 1322 return -EFAULT; 1323 if (len < 0) 1324 return -EINVAL; 1325 1326 memset(&v, 0, sizeof(v)); 1327 1328 switch (optname) { 1329 case SO_DEBUG: 1330 v.val = sock_flag(sk, SOCK_DBG); 1331 break; 1332 1333 case SO_DONTROUTE: 1334 v.val = sock_flag(sk, SOCK_LOCALROUTE); 1335 break; 1336 1337 case SO_BROADCAST: 1338 v.val = sock_flag(sk, SOCK_BROADCAST); 1339 break; 1340 1341 case SO_SNDBUF: 1342 v.val = sk->sk_sndbuf; 1343 break; 1344 1345 case SO_RCVBUF: 1346 v.val = sk->sk_rcvbuf; 1347 break; 1348 1349 case SO_REUSEADDR: 1350 v.val = sk->sk_reuse; 1351 break; 1352 1353 case SO_REUSEPORT: 1354 v.val = sk->sk_reuseport; 1355 break; 1356 1357 case SO_KEEPALIVE: 1358 v.val = sock_flag(sk, SOCK_KEEPOPEN); 1359 break; 1360 1361 case SO_TYPE: 1362 v.val = sk->sk_type; 1363 break; 1364 1365 case SO_PROTOCOL: 1366 v.val = sk->sk_protocol; 1367 break; 1368 1369 case SO_DOMAIN: 1370 v.val = sk->sk_family; 1371 break; 1372 1373 case SO_ERROR: 1374 v.val = -sock_error(sk); 1375 if (v.val == 0) 1376 v.val = xchg(&sk->sk_err_soft, 0); 1377 break; 1378 1379 case SO_OOBINLINE: 1380 v.val = sock_flag(sk, SOCK_URGINLINE); 1381 break; 1382 1383 case SO_NO_CHECK: 1384 v.val = sk->sk_no_check_tx; 1385 break; 1386 1387 case SO_PRIORITY: 1388 v.val = sk->sk_priority; 1389 break; 1390 1391 case SO_LINGER: 1392 lv = sizeof(v.ling); 1393 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1394 v.ling.l_linger = sk->sk_lingertime / HZ; 1395 break; 1396 1397 case SO_BSDCOMPAT: 1398 sock_warn_obsolete_bsdism("getsockopt"); 1399 break; 1400 1401 case SO_TIMESTAMP_OLD: 1402 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1403 !sock_flag(sk, SOCK_TSTAMP_NEW) && 1404 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1405 break; 1406 1407 case SO_TIMESTAMPNS_OLD: 1408 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW); 1409 break; 1410 1411 case SO_TIMESTAMP_NEW: 1412 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW); 1413 break; 1414 1415 case SO_TIMESTAMPNS_NEW: 1416 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW); 1417 break; 1418 1419 case SO_TIMESTAMPING_OLD: 1420 v.val = sk->sk_tsflags; 1421 break; 1422 1423 case SO_RCVTIMEO_OLD: 1424 case SO_RCVTIMEO_NEW: 1425 lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname); 1426 break; 1427 1428 case SO_SNDTIMEO_OLD: 1429 case SO_SNDTIMEO_NEW: 1430 lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname); 1431 break; 1432 1433 case SO_RCVLOWAT: 1434 v.val = sk->sk_rcvlowat; 1435 break; 1436 1437 case SO_SNDLOWAT: 1438 v.val = 1; 1439 break; 1440 1441 case SO_PASSCRED: 1442 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1443 break; 1444 1445 case SO_PEERCRED: 1446 { 1447 struct ucred peercred; 1448 if (len > sizeof(peercred)) 1449 len = sizeof(peercred); 1450 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1451 if (copy_to_user(optval, &peercred, len)) 1452 return -EFAULT; 1453 goto lenout; 1454 } 1455 1456 case SO_PEERGROUPS: 1457 { 1458 int ret, n; 1459 1460 if (!sk->sk_peer_cred) 1461 return -ENODATA; 1462 1463 n = sk->sk_peer_cred->group_info->ngroups; 1464 if (len < n * sizeof(gid_t)) { 1465 len = n * sizeof(gid_t); 1466 return put_user(len, optlen) ? -EFAULT : -ERANGE; 1467 } 1468 len = n * sizeof(gid_t); 1469 1470 ret = groups_to_user((gid_t __user *)optval, 1471 sk->sk_peer_cred->group_info); 1472 if (ret) 1473 return ret; 1474 goto lenout; 1475 } 1476 1477 case SO_PEERNAME: 1478 { 1479 char address[128]; 1480 1481 lv = sock->ops->getname(sock, (struct sockaddr *)address, 2); 1482 if (lv < 0) 1483 return -ENOTCONN; 1484 if (lv < len) 1485 return -EINVAL; 1486 if (copy_to_user(optval, address, len)) 1487 return -EFAULT; 1488 goto lenout; 1489 } 1490 1491 /* Dubious BSD thing... Probably nobody even uses it, but 1492 * the UNIX standard wants it for whatever reason... -DaveM 1493 */ 1494 case SO_ACCEPTCONN: 1495 v.val = sk->sk_state == TCP_LISTEN; 1496 break; 1497 1498 case SO_PASSSEC: 1499 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1500 break; 1501 1502 case SO_PEERSEC: 1503 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1504 1505 case SO_MARK: 1506 v.val = sk->sk_mark; 1507 break; 1508 1509 case SO_RXQ_OVFL: 1510 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1511 break; 1512 1513 case SO_WIFI_STATUS: 1514 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1515 break; 1516 1517 case SO_PEEK_OFF: 1518 if (!sock->ops->set_peek_off) 1519 return -EOPNOTSUPP; 1520 1521 v.val = sk->sk_peek_off; 1522 break; 1523 case SO_NOFCS: 1524 v.val = sock_flag(sk, SOCK_NOFCS); 1525 break; 1526 1527 case SO_BINDTODEVICE: 1528 return sock_getbindtodevice(sk, optval, optlen, len); 1529 1530 case SO_GET_FILTER: 1531 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1532 if (len < 0) 1533 return len; 1534 1535 goto lenout; 1536 1537 case SO_LOCK_FILTER: 1538 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1539 break; 1540 1541 case SO_BPF_EXTENSIONS: 1542 v.val = bpf_tell_extensions(); 1543 break; 1544 1545 case SO_SELECT_ERR_QUEUE: 1546 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1547 break; 1548 1549 #ifdef CONFIG_NET_RX_BUSY_POLL 1550 case SO_BUSY_POLL: 1551 v.val = sk->sk_ll_usec; 1552 break; 1553 #endif 1554 1555 case SO_MAX_PACING_RATE: 1556 if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) { 1557 lv = sizeof(v.ulval); 1558 v.ulval = sk->sk_max_pacing_rate; 1559 } else { 1560 /* 32bit version */ 1561 v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U); 1562 } 1563 break; 1564 1565 case SO_INCOMING_CPU: 1566 v.val = READ_ONCE(sk->sk_incoming_cpu); 1567 break; 1568 1569 case SO_MEMINFO: 1570 { 1571 u32 meminfo[SK_MEMINFO_VARS]; 1572 1573 sk_get_meminfo(sk, meminfo); 1574 1575 len = min_t(unsigned int, len, sizeof(meminfo)); 1576 if (copy_to_user(optval, &meminfo, len)) 1577 return -EFAULT; 1578 1579 goto lenout; 1580 } 1581 1582 #ifdef CONFIG_NET_RX_BUSY_POLL 1583 case SO_INCOMING_NAPI_ID: 1584 v.val = READ_ONCE(sk->sk_napi_id); 1585 1586 /* aggregate non-NAPI IDs down to 0 */ 1587 if (v.val < MIN_NAPI_ID) 1588 v.val = 0; 1589 1590 break; 1591 #endif 1592 1593 case SO_COOKIE: 1594 lv = sizeof(u64); 1595 if (len < lv) 1596 return -EINVAL; 1597 v.val64 = sock_gen_cookie(sk); 1598 break; 1599 1600 case SO_ZEROCOPY: 1601 v.val = sock_flag(sk, SOCK_ZEROCOPY); 1602 break; 1603 1604 case SO_TXTIME: 1605 lv = sizeof(v.txtime); 1606 v.txtime.clockid = sk->sk_clockid; 1607 v.txtime.flags |= sk->sk_txtime_deadline_mode ? 1608 SOF_TXTIME_DEADLINE_MODE : 0; 1609 v.txtime.flags |= sk->sk_txtime_report_errors ? 1610 SOF_TXTIME_REPORT_ERRORS : 0; 1611 break; 1612 1613 case SO_BINDTOIFINDEX: 1614 v.val = sk->sk_bound_dev_if; 1615 break; 1616 1617 default: 1618 /* We implement the SO_SNDLOWAT etc to not be settable 1619 * (1003.1g 7). 1620 */ 1621 return -ENOPROTOOPT; 1622 } 1623 1624 if (len > lv) 1625 len = lv; 1626 if (copy_to_user(optval, &v, len)) 1627 return -EFAULT; 1628 lenout: 1629 if (put_user(len, optlen)) 1630 return -EFAULT; 1631 return 0; 1632 } 1633 1634 /* 1635 * Initialize an sk_lock. 1636 * 1637 * (We also register the sk_lock with the lock validator.) 1638 */ 1639 static inline void sock_lock_init(struct sock *sk) 1640 { 1641 if (sk->sk_kern_sock) 1642 sock_lock_init_class_and_name( 1643 sk, 1644 af_family_kern_slock_key_strings[sk->sk_family], 1645 af_family_kern_slock_keys + sk->sk_family, 1646 af_family_kern_key_strings[sk->sk_family], 1647 af_family_kern_keys + sk->sk_family); 1648 else 1649 sock_lock_init_class_and_name( 1650 sk, 1651 af_family_slock_key_strings[sk->sk_family], 1652 af_family_slock_keys + sk->sk_family, 1653 af_family_key_strings[sk->sk_family], 1654 af_family_keys + sk->sk_family); 1655 } 1656 1657 /* 1658 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1659 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1660 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1661 */ 1662 static void sock_copy(struct sock *nsk, const struct sock *osk) 1663 { 1664 const struct proto *prot = READ_ONCE(osk->sk_prot); 1665 #ifdef CONFIG_SECURITY_NETWORK 1666 void *sptr = nsk->sk_security; 1667 #endif 1668 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1669 1670 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1671 prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1672 1673 #ifdef CONFIG_SECURITY_NETWORK 1674 nsk->sk_security = sptr; 1675 security_sk_clone(osk, nsk); 1676 #endif 1677 } 1678 1679 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1680 int family) 1681 { 1682 struct sock *sk; 1683 struct kmem_cache *slab; 1684 1685 slab = prot->slab; 1686 if (slab != NULL) { 1687 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1688 if (!sk) 1689 return sk; 1690 if (want_init_on_alloc(priority)) 1691 sk_prot_clear_nulls(sk, prot->obj_size); 1692 } else 1693 sk = kmalloc(prot->obj_size, priority); 1694 1695 if (sk != NULL) { 1696 if (security_sk_alloc(sk, family, priority)) 1697 goto out_free; 1698 1699 if (!try_module_get(prot->owner)) 1700 goto out_free_sec; 1701 sk_tx_queue_clear(sk); 1702 } 1703 1704 return sk; 1705 1706 out_free_sec: 1707 security_sk_free(sk); 1708 out_free: 1709 if (slab != NULL) 1710 kmem_cache_free(slab, sk); 1711 else 1712 kfree(sk); 1713 return NULL; 1714 } 1715 1716 static void sk_prot_free(struct proto *prot, struct sock *sk) 1717 { 1718 struct kmem_cache *slab; 1719 struct module *owner; 1720 1721 owner = prot->owner; 1722 slab = prot->slab; 1723 1724 cgroup_sk_free(&sk->sk_cgrp_data); 1725 mem_cgroup_sk_free(sk); 1726 security_sk_free(sk); 1727 if (slab != NULL) 1728 kmem_cache_free(slab, sk); 1729 else 1730 kfree(sk); 1731 module_put(owner); 1732 } 1733 1734 /** 1735 * sk_alloc - All socket objects are allocated here 1736 * @net: the applicable net namespace 1737 * @family: protocol family 1738 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1739 * @prot: struct proto associated with this new sock instance 1740 * @kern: is this to be a kernel socket? 1741 */ 1742 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1743 struct proto *prot, int kern) 1744 { 1745 struct sock *sk; 1746 1747 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1748 if (sk) { 1749 sk->sk_family = family; 1750 /* 1751 * See comment in struct sock definition to understand 1752 * why we need sk_prot_creator -acme 1753 */ 1754 sk->sk_prot = sk->sk_prot_creator = prot; 1755 sk->sk_kern_sock = kern; 1756 sock_lock_init(sk); 1757 sk->sk_net_refcnt = kern ? 0 : 1; 1758 if (likely(sk->sk_net_refcnt)) { 1759 get_net(net); 1760 sock_inuse_add(net, 1); 1761 } 1762 1763 sock_net_set(sk, net); 1764 refcount_set(&sk->sk_wmem_alloc, 1); 1765 1766 mem_cgroup_sk_alloc(sk); 1767 cgroup_sk_alloc(&sk->sk_cgrp_data); 1768 sock_update_classid(&sk->sk_cgrp_data); 1769 sock_update_netprioidx(&sk->sk_cgrp_data); 1770 sk_tx_queue_clear(sk); 1771 } 1772 1773 return sk; 1774 } 1775 EXPORT_SYMBOL(sk_alloc); 1776 1777 /* Sockets having SOCK_RCU_FREE will call this function after one RCU 1778 * grace period. This is the case for UDP sockets and TCP listeners. 1779 */ 1780 static void __sk_destruct(struct rcu_head *head) 1781 { 1782 struct sock *sk = container_of(head, struct sock, sk_rcu); 1783 struct sk_filter *filter; 1784 1785 if (sk->sk_destruct) 1786 sk->sk_destruct(sk); 1787 1788 filter = rcu_dereference_check(sk->sk_filter, 1789 refcount_read(&sk->sk_wmem_alloc) == 0); 1790 if (filter) { 1791 sk_filter_uncharge(sk, filter); 1792 RCU_INIT_POINTER(sk->sk_filter, NULL); 1793 } 1794 1795 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1796 1797 #ifdef CONFIG_BPF_SYSCALL 1798 bpf_sk_storage_free(sk); 1799 #endif 1800 1801 if (atomic_read(&sk->sk_omem_alloc)) 1802 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1803 __func__, atomic_read(&sk->sk_omem_alloc)); 1804 1805 if (sk->sk_frag.page) { 1806 put_page(sk->sk_frag.page); 1807 sk->sk_frag.page = NULL; 1808 } 1809 1810 if (sk->sk_peer_cred) 1811 put_cred(sk->sk_peer_cred); 1812 put_pid(sk->sk_peer_pid); 1813 if (likely(sk->sk_net_refcnt)) 1814 put_net(sock_net(sk)); 1815 sk_prot_free(sk->sk_prot_creator, sk); 1816 } 1817 1818 void sk_destruct(struct sock *sk) 1819 { 1820 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE); 1821 1822 if (rcu_access_pointer(sk->sk_reuseport_cb)) { 1823 reuseport_detach_sock(sk); 1824 use_call_rcu = true; 1825 } 1826 1827 if (use_call_rcu) 1828 call_rcu(&sk->sk_rcu, __sk_destruct); 1829 else 1830 __sk_destruct(&sk->sk_rcu); 1831 } 1832 1833 static void __sk_free(struct sock *sk) 1834 { 1835 if (likely(sk->sk_net_refcnt)) 1836 sock_inuse_add(sock_net(sk), -1); 1837 1838 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk))) 1839 sock_diag_broadcast_destroy(sk); 1840 else 1841 sk_destruct(sk); 1842 } 1843 1844 void sk_free(struct sock *sk) 1845 { 1846 /* 1847 * We subtract one from sk_wmem_alloc and can know if 1848 * some packets are still in some tx queue. 1849 * If not null, sock_wfree() will call __sk_free(sk) later 1850 */ 1851 if (refcount_dec_and_test(&sk->sk_wmem_alloc)) 1852 __sk_free(sk); 1853 } 1854 EXPORT_SYMBOL(sk_free); 1855 1856 static void sk_init_common(struct sock *sk) 1857 { 1858 skb_queue_head_init(&sk->sk_receive_queue); 1859 skb_queue_head_init(&sk->sk_write_queue); 1860 skb_queue_head_init(&sk->sk_error_queue); 1861 1862 rwlock_init(&sk->sk_callback_lock); 1863 lockdep_set_class_and_name(&sk->sk_receive_queue.lock, 1864 af_rlock_keys + sk->sk_family, 1865 af_family_rlock_key_strings[sk->sk_family]); 1866 lockdep_set_class_and_name(&sk->sk_write_queue.lock, 1867 af_wlock_keys + sk->sk_family, 1868 af_family_wlock_key_strings[sk->sk_family]); 1869 lockdep_set_class_and_name(&sk->sk_error_queue.lock, 1870 af_elock_keys + sk->sk_family, 1871 af_family_elock_key_strings[sk->sk_family]); 1872 lockdep_set_class_and_name(&sk->sk_callback_lock, 1873 af_callback_keys + sk->sk_family, 1874 af_family_clock_key_strings[sk->sk_family]); 1875 } 1876 1877 /** 1878 * sk_clone_lock - clone a socket, and lock its clone 1879 * @sk: the socket to clone 1880 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1881 * 1882 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1883 */ 1884 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1885 { 1886 struct proto *prot = READ_ONCE(sk->sk_prot); 1887 struct sock *newsk; 1888 bool is_charged = true; 1889 1890 newsk = sk_prot_alloc(prot, priority, sk->sk_family); 1891 if (newsk != NULL) { 1892 struct sk_filter *filter; 1893 1894 sock_copy(newsk, sk); 1895 1896 newsk->sk_prot_creator = prot; 1897 1898 /* SANITY */ 1899 if (likely(newsk->sk_net_refcnt)) 1900 get_net(sock_net(newsk)); 1901 sk_node_init(&newsk->sk_node); 1902 sock_lock_init(newsk); 1903 bh_lock_sock(newsk); 1904 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1905 newsk->sk_backlog.len = 0; 1906 1907 atomic_set(&newsk->sk_rmem_alloc, 0); 1908 /* 1909 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1910 */ 1911 refcount_set(&newsk->sk_wmem_alloc, 1); 1912 atomic_set(&newsk->sk_omem_alloc, 0); 1913 sk_init_common(newsk); 1914 1915 newsk->sk_dst_cache = NULL; 1916 newsk->sk_dst_pending_confirm = 0; 1917 newsk->sk_wmem_queued = 0; 1918 newsk->sk_forward_alloc = 0; 1919 atomic_set(&newsk->sk_drops, 0); 1920 newsk->sk_send_head = NULL; 1921 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1922 atomic_set(&newsk->sk_zckey, 0); 1923 1924 sock_reset_flag(newsk, SOCK_DONE); 1925 1926 /* sk->sk_memcg will be populated at accept() time */ 1927 newsk->sk_memcg = NULL; 1928 1929 cgroup_sk_clone(&newsk->sk_cgrp_data); 1930 1931 rcu_read_lock(); 1932 filter = rcu_dereference(sk->sk_filter); 1933 if (filter != NULL) 1934 /* though it's an empty new sock, the charging may fail 1935 * if sysctl_optmem_max was changed between creation of 1936 * original socket and cloning 1937 */ 1938 is_charged = sk_filter_charge(newsk, filter); 1939 RCU_INIT_POINTER(newsk->sk_filter, filter); 1940 rcu_read_unlock(); 1941 1942 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) { 1943 /* We need to make sure that we don't uncharge the new 1944 * socket if we couldn't charge it in the first place 1945 * as otherwise we uncharge the parent's filter. 1946 */ 1947 if (!is_charged) 1948 RCU_INIT_POINTER(newsk->sk_filter, NULL); 1949 sk_free_unlock_clone(newsk); 1950 newsk = NULL; 1951 goto out; 1952 } 1953 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL); 1954 1955 if (bpf_sk_storage_clone(sk, newsk)) { 1956 sk_free_unlock_clone(newsk); 1957 newsk = NULL; 1958 goto out; 1959 } 1960 1961 /* Clear sk_user_data if parent had the pointer tagged 1962 * as not suitable for copying when cloning. 1963 */ 1964 if (sk_user_data_is_nocopy(newsk)) 1965 newsk->sk_user_data = NULL; 1966 1967 newsk->sk_err = 0; 1968 newsk->sk_err_soft = 0; 1969 newsk->sk_priority = 0; 1970 newsk->sk_incoming_cpu = raw_smp_processor_id(); 1971 if (likely(newsk->sk_net_refcnt)) 1972 sock_inuse_add(sock_net(newsk), 1); 1973 1974 /* 1975 * Before updating sk_refcnt, we must commit prior changes to memory 1976 * (Documentation/RCU/rculist_nulls.txt for details) 1977 */ 1978 smp_wmb(); 1979 refcount_set(&newsk->sk_refcnt, 2); 1980 1981 /* 1982 * Increment the counter in the same struct proto as the master 1983 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1984 * is the same as sk->sk_prot->socks, as this field was copied 1985 * with memcpy). 1986 * 1987 * This _changes_ the previous behaviour, where 1988 * tcp_create_openreq_child always was incrementing the 1989 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1990 * to be taken into account in all callers. -acme 1991 */ 1992 sk_refcnt_debug_inc(newsk); 1993 sk_set_socket(newsk, NULL); 1994 sk_tx_queue_clear(newsk); 1995 RCU_INIT_POINTER(newsk->sk_wq, NULL); 1996 1997 if (newsk->sk_prot->sockets_allocated) 1998 sk_sockets_allocated_inc(newsk); 1999 2000 if (sock_needs_netstamp(sk) && 2001 newsk->sk_flags & SK_FLAGS_TIMESTAMP) 2002 net_enable_timestamp(); 2003 } 2004 out: 2005 return newsk; 2006 } 2007 EXPORT_SYMBOL_GPL(sk_clone_lock); 2008 2009 void sk_free_unlock_clone(struct sock *sk) 2010 { 2011 /* It is still raw copy of parent, so invalidate 2012 * destructor and make plain sk_free() */ 2013 sk->sk_destruct = NULL; 2014 bh_unlock_sock(sk); 2015 sk_free(sk); 2016 } 2017 EXPORT_SYMBOL_GPL(sk_free_unlock_clone); 2018 2019 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 2020 { 2021 u32 max_segs = 1; 2022 2023 sk_dst_set(sk, dst); 2024 sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps; 2025 if (sk->sk_route_caps & NETIF_F_GSO) 2026 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 2027 sk->sk_route_caps &= ~sk->sk_route_nocaps; 2028 if (sk_can_gso(sk)) { 2029 if (dst->header_len && !xfrm_dst_offload_ok(dst)) { 2030 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 2031 } else { 2032 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 2033 sk->sk_gso_max_size = dst->dev->gso_max_size; 2034 max_segs = max_t(u32, dst->dev->gso_max_segs, 1); 2035 } 2036 } 2037 sk->sk_gso_max_segs = max_segs; 2038 } 2039 EXPORT_SYMBOL_GPL(sk_setup_caps); 2040 2041 /* 2042 * Simple resource managers for sockets. 2043 */ 2044 2045 2046 /* 2047 * Write buffer destructor automatically called from kfree_skb. 2048 */ 2049 void sock_wfree(struct sk_buff *skb) 2050 { 2051 struct sock *sk = skb->sk; 2052 unsigned int len = skb->truesize; 2053 2054 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 2055 /* 2056 * Keep a reference on sk_wmem_alloc, this will be released 2057 * after sk_write_space() call 2058 */ 2059 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc)); 2060 sk->sk_write_space(sk); 2061 len = 1; 2062 } 2063 /* 2064 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 2065 * could not do because of in-flight packets 2066 */ 2067 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc)) 2068 __sk_free(sk); 2069 } 2070 EXPORT_SYMBOL(sock_wfree); 2071 2072 /* This variant of sock_wfree() is used by TCP, 2073 * since it sets SOCK_USE_WRITE_QUEUE. 2074 */ 2075 void __sock_wfree(struct sk_buff *skb) 2076 { 2077 struct sock *sk = skb->sk; 2078 2079 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc)) 2080 __sk_free(sk); 2081 } 2082 2083 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) 2084 { 2085 skb_orphan(skb); 2086 skb->sk = sk; 2087 #ifdef CONFIG_INET 2088 if (unlikely(!sk_fullsock(sk))) { 2089 skb->destructor = sock_edemux; 2090 sock_hold(sk); 2091 return; 2092 } 2093 #endif 2094 skb->destructor = sock_wfree; 2095 skb_set_hash_from_sk(skb, sk); 2096 /* 2097 * We used to take a refcount on sk, but following operation 2098 * is enough to guarantee sk_free() wont free this sock until 2099 * all in-flight packets are completed 2100 */ 2101 refcount_add(skb->truesize, &sk->sk_wmem_alloc); 2102 } 2103 EXPORT_SYMBOL(skb_set_owner_w); 2104 2105 static bool can_skb_orphan_partial(const struct sk_buff *skb) 2106 { 2107 #ifdef CONFIG_TLS_DEVICE 2108 /* Drivers depend on in-order delivery for crypto offload, 2109 * partial orphan breaks out-of-order-OK logic. 2110 */ 2111 if (skb->decrypted) 2112 return false; 2113 #endif 2114 return (skb->destructor == sock_wfree || 2115 (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree)); 2116 } 2117 2118 /* This helper is used by netem, as it can hold packets in its 2119 * delay queue. We want to allow the owner socket to send more 2120 * packets, as if they were already TX completed by a typical driver. 2121 * But we also want to keep skb->sk set because some packet schedulers 2122 * rely on it (sch_fq for example). 2123 */ 2124 void skb_orphan_partial(struct sk_buff *skb) 2125 { 2126 if (skb_is_tcp_pure_ack(skb)) 2127 return; 2128 2129 if (can_skb_orphan_partial(skb)) { 2130 struct sock *sk = skb->sk; 2131 2132 if (refcount_inc_not_zero(&sk->sk_refcnt)) { 2133 WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc)); 2134 skb->destructor = sock_efree; 2135 } 2136 } else { 2137 skb_orphan(skb); 2138 } 2139 } 2140 EXPORT_SYMBOL(skb_orphan_partial); 2141 2142 /* 2143 * Read buffer destructor automatically called from kfree_skb. 2144 */ 2145 void sock_rfree(struct sk_buff *skb) 2146 { 2147 struct sock *sk = skb->sk; 2148 unsigned int len = skb->truesize; 2149 2150 atomic_sub(len, &sk->sk_rmem_alloc); 2151 sk_mem_uncharge(sk, len); 2152 } 2153 EXPORT_SYMBOL(sock_rfree); 2154 2155 /* 2156 * Buffer destructor for skbs that are not used directly in read or write 2157 * path, e.g. for error handler skbs. Automatically called from kfree_skb. 2158 */ 2159 void sock_efree(struct sk_buff *skb) 2160 { 2161 sock_put(skb->sk); 2162 } 2163 EXPORT_SYMBOL(sock_efree); 2164 2165 /* Buffer destructor for prefetch/receive path where reference count may 2166 * not be held, e.g. for listen sockets. 2167 */ 2168 #ifdef CONFIG_INET 2169 void sock_pfree(struct sk_buff *skb) 2170 { 2171 if (sk_is_refcounted(skb->sk)) 2172 sock_gen_put(skb->sk); 2173 } 2174 EXPORT_SYMBOL(sock_pfree); 2175 #endif /* CONFIG_INET */ 2176 2177 kuid_t sock_i_uid(struct sock *sk) 2178 { 2179 kuid_t uid; 2180 2181 read_lock_bh(&sk->sk_callback_lock); 2182 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 2183 read_unlock_bh(&sk->sk_callback_lock); 2184 return uid; 2185 } 2186 EXPORT_SYMBOL(sock_i_uid); 2187 2188 unsigned long sock_i_ino(struct sock *sk) 2189 { 2190 unsigned long ino; 2191 2192 read_lock_bh(&sk->sk_callback_lock); 2193 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 2194 read_unlock_bh(&sk->sk_callback_lock); 2195 return ino; 2196 } 2197 EXPORT_SYMBOL(sock_i_ino); 2198 2199 /* 2200 * Allocate a skb from the socket's send buffer. 2201 */ 2202 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 2203 gfp_t priority) 2204 { 2205 if (force || 2206 refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) { 2207 struct sk_buff *skb = alloc_skb(size, priority); 2208 2209 if (skb) { 2210 skb_set_owner_w(skb, sk); 2211 return skb; 2212 } 2213 } 2214 return NULL; 2215 } 2216 EXPORT_SYMBOL(sock_wmalloc); 2217 2218 static void sock_ofree(struct sk_buff *skb) 2219 { 2220 struct sock *sk = skb->sk; 2221 2222 atomic_sub(skb->truesize, &sk->sk_omem_alloc); 2223 } 2224 2225 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 2226 gfp_t priority) 2227 { 2228 struct sk_buff *skb; 2229 2230 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */ 2231 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) > 2232 sysctl_optmem_max) 2233 return NULL; 2234 2235 skb = alloc_skb(size, priority); 2236 if (!skb) 2237 return NULL; 2238 2239 atomic_add(skb->truesize, &sk->sk_omem_alloc); 2240 skb->sk = sk; 2241 skb->destructor = sock_ofree; 2242 return skb; 2243 } 2244 2245 /* 2246 * Allocate a memory block from the socket's option memory buffer. 2247 */ 2248 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 2249 { 2250 if ((unsigned int)size <= sysctl_optmem_max && 2251 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 2252 void *mem; 2253 /* First do the add, to avoid the race if kmalloc 2254 * might sleep. 2255 */ 2256 atomic_add(size, &sk->sk_omem_alloc); 2257 mem = kmalloc(size, priority); 2258 if (mem) 2259 return mem; 2260 atomic_sub(size, &sk->sk_omem_alloc); 2261 } 2262 return NULL; 2263 } 2264 EXPORT_SYMBOL(sock_kmalloc); 2265 2266 /* Free an option memory block. Note, we actually want the inline 2267 * here as this allows gcc to detect the nullify and fold away the 2268 * condition entirely. 2269 */ 2270 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size, 2271 const bool nullify) 2272 { 2273 if (WARN_ON_ONCE(!mem)) 2274 return; 2275 if (nullify) 2276 kzfree(mem); 2277 else 2278 kfree(mem); 2279 atomic_sub(size, &sk->sk_omem_alloc); 2280 } 2281 2282 void sock_kfree_s(struct sock *sk, void *mem, int size) 2283 { 2284 __sock_kfree_s(sk, mem, size, false); 2285 } 2286 EXPORT_SYMBOL(sock_kfree_s); 2287 2288 void sock_kzfree_s(struct sock *sk, void *mem, int size) 2289 { 2290 __sock_kfree_s(sk, mem, size, true); 2291 } 2292 EXPORT_SYMBOL(sock_kzfree_s); 2293 2294 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 2295 I think, these locks should be removed for datagram sockets. 2296 */ 2297 static long sock_wait_for_wmem(struct sock *sk, long timeo) 2298 { 2299 DEFINE_WAIT(wait); 2300 2301 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); 2302 for (;;) { 2303 if (!timeo) 2304 break; 2305 if (signal_pending(current)) 2306 break; 2307 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 2308 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 2309 if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) 2310 break; 2311 if (sk->sk_shutdown & SEND_SHUTDOWN) 2312 break; 2313 if (sk->sk_err) 2314 break; 2315 timeo = schedule_timeout(timeo); 2316 } 2317 finish_wait(sk_sleep(sk), &wait); 2318 return timeo; 2319 } 2320 2321 2322 /* 2323 * Generic send/receive buffer handlers 2324 */ 2325 2326 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 2327 unsigned long data_len, int noblock, 2328 int *errcode, int max_page_order) 2329 { 2330 struct sk_buff *skb; 2331 long timeo; 2332 int err; 2333 2334 timeo = sock_sndtimeo(sk, noblock); 2335 for (;;) { 2336 err = sock_error(sk); 2337 if (err != 0) 2338 goto failure; 2339 2340 err = -EPIPE; 2341 if (sk->sk_shutdown & SEND_SHUTDOWN) 2342 goto failure; 2343 2344 if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf)) 2345 break; 2346 2347 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); 2348 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 2349 err = -EAGAIN; 2350 if (!timeo) 2351 goto failure; 2352 if (signal_pending(current)) 2353 goto interrupted; 2354 timeo = sock_wait_for_wmem(sk, timeo); 2355 } 2356 skb = alloc_skb_with_frags(header_len, data_len, max_page_order, 2357 errcode, sk->sk_allocation); 2358 if (skb) 2359 skb_set_owner_w(skb, sk); 2360 return skb; 2361 2362 interrupted: 2363 err = sock_intr_errno(timeo); 2364 failure: 2365 *errcode = err; 2366 return NULL; 2367 } 2368 EXPORT_SYMBOL(sock_alloc_send_pskb); 2369 2370 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 2371 int noblock, int *errcode) 2372 { 2373 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 2374 } 2375 EXPORT_SYMBOL(sock_alloc_send_skb); 2376 2377 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, 2378 struct sockcm_cookie *sockc) 2379 { 2380 u32 tsflags; 2381 2382 switch (cmsg->cmsg_type) { 2383 case SO_MARK: 2384 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 2385 return -EPERM; 2386 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 2387 return -EINVAL; 2388 sockc->mark = *(u32 *)CMSG_DATA(cmsg); 2389 break; 2390 case SO_TIMESTAMPING_OLD: 2391 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 2392 return -EINVAL; 2393 2394 tsflags = *(u32 *)CMSG_DATA(cmsg); 2395 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK) 2396 return -EINVAL; 2397 2398 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK; 2399 sockc->tsflags |= tsflags; 2400 break; 2401 case SCM_TXTIME: 2402 if (!sock_flag(sk, SOCK_TXTIME)) 2403 return -EINVAL; 2404 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64))) 2405 return -EINVAL; 2406 sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg)); 2407 break; 2408 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */ 2409 case SCM_RIGHTS: 2410 case SCM_CREDENTIALS: 2411 break; 2412 default: 2413 return -EINVAL; 2414 } 2415 return 0; 2416 } 2417 EXPORT_SYMBOL(__sock_cmsg_send); 2418 2419 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 2420 struct sockcm_cookie *sockc) 2421 { 2422 struct cmsghdr *cmsg; 2423 int ret; 2424 2425 for_each_cmsghdr(cmsg, msg) { 2426 if (!CMSG_OK(msg, cmsg)) 2427 return -EINVAL; 2428 if (cmsg->cmsg_level != SOL_SOCKET) 2429 continue; 2430 ret = __sock_cmsg_send(sk, msg, cmsg, sockc); 2431 if (ret) 2432 return ret; 2433 } 2434 return 0; 2435 } 2436 EXPORT_SYMBOL(sock_cmsg_send); 2437 2438 static void sk_enter_memory_pressure(struct sock *sk) 2439 { 2440 if (!sk->sk_prot->enter_memory_pressure) 2441 return; 2442 2443 sk->sk_prot->enter_memory_pressure(sk); 2444 } 2445 2446 static void sk_leave_memory_pressure(struct sock *sk) 2447 { 2448 if (sk->sk_prot->leave_memory_pressure) { 2449 sk->sk_prot->leave_memory_pressure(sk); 2450 } else { 2451 unsigned long *memory_pressure = sk->sk_prot->memory_pressure; 2452 2453 if (memory_pressure && READ_ONCE(*memory_pressure)) 2454 WRITE_ONCE(*memory_pressure, 0); 2455 } 2456 } 2457 2458 #define SKB_FRAG_PAGE_ORDER get_order(32768) 2459 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2460 2461 /** 2462 * skb_page_frag_refill - check that a page_frag contains enough room 2463 * @sz: minimum size of the fragment we want to get 2464 * @pfrag: pointer to page_frag 2465 * @gfp: priority for memory allocation 2466 * 2467 * Note: While this allocator tries to use high order pages, there is 2468 * no guarantee that allocations succeed. Therefore, @sz MUST be 2469 * less or equal than PAGE_SIZE. 2470 */ 2471 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp) 2472 { 2473 if (pfrag->page) { 2474 if (page_ref_count(pfrag->page) == 1) { 2475 pfrag->offset = 0; 2476 return true; 2477 } 2478 if (pfrag->offset + sz <= pfrag->size) 2479 return true; 2480 put_page(pfrag->page); 2481 } 2482 2483 pfrag->offset = 0; 2484 if (SKB_FRAG_PAGE_ORDER && 2485 !static_branch_unlikely(&net_high_order_alloc_disable_key)) { 2486 /* Avoid direct reclaim but allow kswapd to wake */ 2487 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) | 2488 __GFP_COMP | __GFP_NOWARN | 2489 __GFP_NORETRY, 2490 SKB_FRAG_PAGE_ORDER); 2491 if (likely(pfrag->page)) { 2492 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER; 2493 return true; 2494 } 2495 } 2496 pfrag->page = alloc_page(gfp); 2497 if (likely(pfrag->page)) { 2498 pfrag->size = PAGE_SIZE; 2499 return true; 2500 } 2501 return false; 2502 } 2503 EXPORT_SYMBOL(skb_page_frag_refill); 2504 2505 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 2506 { 2507 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 2508 return true; 2509 2510 sk_enter_memory_pressure(sk); 2511 sk_stream_moderate_sndbuf(sk); 2512 return false; 2513 } 2514 EXPORT_SYMBOL(sk_page_frag_refill); 2515 2516 static void __lock_sock(struct sock *sk) 2517 __releases(&sk->sk_lock.slock) 2518 __acquires(&sk->sk_lock.slock) 2519 { 2520 DEFINE_WAIT(wait); 2521 2522 for (;;) { 2523 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 2524 TASK_UNINTERRUPTIBLE); 2525 spin_unlock_bh(&sk->sk_lock.slock); 2526 schedule(); 2527 spin_lock_bh(&sk->sk_lock.slock); 2528 if (!sock_owned_by_user(sk)) 2529 break; 2530 } 2531 finish_wait(&sk->sk_lock.wq, &wait); 2532 } 2533 2534 void __release_sock(struct sock *sk) 2535 __releases(&sk->sk_lock.slock) 2536 __acquires(&sk->sk_lock.slock) 2537 { 2538 struct sk_buff *skb, *next; 2539 2540 while ((skb = sk->sk_backlog.head) != NULL) { 2541 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 2542 2543 spin_unlock_bh(&sk->sk_lock.slock); 2544 2545 do { 2546 next = skb->next; 2547 prefetch(next); 2548 WARN_ON_ONCE(skb_dst_is_noref(skb)); 2549 skb_mark_not_on_list(skb); 2550 sk_backlog_rcv(sk, skb); 2551 2552 cond_resched(); 2553 2554 skb = next; 2555 } while (skb != NULL); 2556 2557 spin_lock_bh(&sk->sk_lock.slock); 2558 } 2559 2560 /* 2561 * Doing the zeroing here guarantee we can not loop forever 2562 * while a wild producer attempts to flood us. 2563 */ 2564 sk->sk_backlog.len = 0; 2565 } 2566 2567 void __sk_flush_backlog(struct sock *sk) 2568 { 2569 spin_lock_bh(&sk->sk_lock.slock); 2570 __release_sock(sk); 2571 spin_unlock_bh(&sk->sk_lock.slock); 2572 } 2573 2574 /** 2575 * sk_wait_data - wait for data to arrive at sk_receive_queue 2576 * @sk: sock to wait on 2577 * @timeo: for how long 2578 * @skb: last skb seen on sk_receive_queue 2579 * 2580 * Now socket state including sk->sk_err is changed only under lock, 2581 * hence we may omit checks after joining wait queue. 2582 * We check receive queue before schedule() only as optimization; 2583 * it is very likely that release_sock() added new data. 2584 */ 2585 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb) 2586 { 2587 DEFINE_WAIT_FUNC(wait, woken_wake_function); 2588 int rc; 2589 2590 add_wait_queue(sk_sleep(sk), &wait); 2591 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); 2592 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait); 2593 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); 2594 remove_wait_queue(sk_sleep(sk), &wait); 2595 return rc; 2596 } 2597 EXPORT_SYMBOL(sk_wait_data); 2598 2599 /** 2600 * __sk_mem_raise_allocated - increase memory_allocated 2601 * @sk: socket 2602 * @size: memory size to allocate 2603 * @amt: pages to allocate 2604 * @kind: allocation type 2605 * 2606 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc 2607 */ 2608 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind) 2609 { 2610 struct proto *prot = sk->sk_prot; 2611 long allocated = sk_memory_allocated_add(sk, amt); 2612 bool charged = true; 2613 2614 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 2615 !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt))) 2616 goto suppress_allocation; 2617 2618 /* Under limit. */ 2619 if (allocated <= sk_prot_mem_limits(sk, 0)) { 2620 sk_leave_memory_pressure(sk); 2621 return 1; 2622 } 2623 2624 /* Under pressure. */ 2625 if (allocated > sk_prot_mem_limits(sk, 1)) 2626 sk_enter_memory_pressure(sk); 2627 2628 /* Over hard limit. */ 2629 if (allocated > sk_prot_mem_limits(sk, 2)) 2630 goto suppress_allocation; 2631 2632 /* guarantee minimum buffer size under pressure */ 2633 if (kind == SK_MEM_RECV) { 2634 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot)) 2635 return 1; 2636 2637 } else { /* SK_MEM_SEND */ 2638 int wmem0 = sk_get_wmem0(sk, prot); 2639 2640 if (sk->sk_type == SOCK_STREAM) { 2641 if (sk->sk_wmem_queued < wmem0) 2642 return 1; 2643 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) { 2644 return 1; 2645 } 2646 } 2647 2648 if (sk_has_memory_pressure(sk)) { 2649 u64 alloc; 2650 2651 if (!sk_under_memory_pressure(sk)) 2652 return 1; 2653 alloc = sk_sockets_allocated_read_positive(sk); 2654 if (sk_prot_mem_limits(sk, 2) > alloc * 2655 sk_mem_pages(sk->sk_wmem_queued + 2656 atomic_read(&sk->sk_rmem_alloc) + 2657 sk->sk_forward_alloc)) 2658 return 1; 2659 } 2660 2661 suppress_allocation: 2662 2663 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2664 sk_stream_moderate_sndbuf(sk); 2665 2666 /* Fail only if socket is _under_ its sndbuf. 2667 * In this case we cannot block, so that we have to fail. 2668 */ 2669 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2670 return 1; 2671 } 2672 2673 if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged)) 2674 trace_sock_exceed_buf_limit(sk, prot, allocated, kind); 2675 2676 sk_memory_allocated_sub(sk, amt); 2677 2678 if (mem_cgroup_sockets_enabled && sk->sk_memcg) 2679 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt); 2680 2681 return 0; 2682 } 2683 EXPORT_SYMBOL(__sk_mem_raise_allocated); 2684 2685 /** 2686 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 2687 * @sk: socket 2688 * @size: memory size to allocate 2689 * @kind: allocation type 2690 * 2691 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 2692 * rmem allocation. This function assumes that protocols which have 2693 * memory_pressure use sk_wmem_queued as write buffer accounting. 2694 */ 2695 int __sk_mem_schedule(struct sock *sk, int size, int kind) 2696 { 2697 int ret, amt = sk_mem_pages(size); 2698 2699 sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT; 2700 ret = __sk_mem_raise_allocated(sk, size, amt, kind); 2701 if (!ret) 2702 sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT; 2703 return ret; 2704 } 2705 EXPORT_SYMBOL(__sk_mem_schedule); 2706 2707 /** 2708 * __sk_mem_reduce_allocated - reclaim memory_allocated 2709 * @sk: socket 2710 * @amount: number of quanta 2711 * 2712 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc 2713 */ 2714 void __sk_mem_reduce_allocated(struct sock *sk, int amount) 2715 { 2716 sk_memory_allocated_sub(sk, amount); 2717 2718 if (mem_cgroup_sockets_enabled && sk->sk_memcg) 2719 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount); 2720 2721 if (sk_under_memory_pressure(sk) && 2722 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2723 sk_leave_memory_pressure(sk); 2724 } 2725 EXPORT_SYMBOL(__sk_mem_reduce_allocated); 2726 2727 /** 2728 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated 2729 * @sk: socket 2730 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple) 2731 */ 2732 void __sk_mem_reclaim(struct sock *sk, int amount) 2733 { 2734 amount >>= SK_MEM_QUANTUM_SHIFT; 2735 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT; 2736 __sk_mem_reduce_allocated(sk, amount); 2737 } 2738 EXPORT_SYMBOL(__sk_mem_reclaim); 2739 2740 int sk_set_peek_off(struct sock *sk, int val) 2741 { 2742 sk->sk_peek_off = val; 2743 return 0; 2744 } 2745 EXPORT_SYMBOL_GPL(sk_set_peek_off); 2746 2747 /* 2748 * Set of default routines for initialising struct proto_ops when 2749 * the protocol does not support a particular function. In certain 2750 * cases where it makes no sense for a protocol to have a "do nothing" 2751 * function, some default processing is provided. 2752 */ 2753 2754 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2755 { 2756 return -EOPNOTSUPP; 2757 } 2758 EXPORT_SYMBOL(sock_no_bind); 2759 2760 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2761 int len, int flags) 2762 { 2763 return -EOPNOTSUPP; 2764 } 2765 EXPORT_SYMBOL(sock_no_connect); 2766 2767 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2768 { 2769 return -EOPNOTSUPP; 2770 } 2771 EXPORT_SYMBOL(sock_no_socketpair); 2772 2773 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags, 2774 bool kern) 2775 { 2776 return -EOPNOTSUPP; 2777 } 2778 EXPORT_SYMBOL(sock_no_accept); 2779 2780 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2781 int peer) 2782 { 2783 return -EOPNOTSUPP; 2784 } 2785 EXPORT_SYMBOL(sock_no_getname); 2786 2787 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2788 { 2789 return -EOPNOTSUPP; 2790 } 2791 EXPORT_SYMBOL(sock_no_ioctl); 2792 2793 int sock_no_listen(struct socket *sock, int backlog) 2794 { 2795 return -EOPNOTSUPP; 2796 } 2797 EXPORT_SYMBOL(sock_no_listen); 2798 2799 int sock_no_shutdown(struct socket *sock, int how) 2800 { 2801 return -EOPNOTSUPP; 2802 } 2803 EXPORT_SYMBOL(sock_no_shutdown); 2804 2805 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2806 char __user *optval, unsigned int optlen) 2807 { 2808 return -EOPNOTSUPP; 2809 } 2810 EXPORT_SYMBOL(sock_no_setsockopt); 2811 2812 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2813 char __user *optval, int __user *optlen) 2814 { 2815 return -EOPNOTSUPP; 2816 } 2817 EXPORT_SYMBOL(sock_no_getsockopt); 2818 2819 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len) 2820 { 2821 return -EOPNOTSUPP; 2822 } 2823 EXPORT_SYMBOL(sock_no_sendmsg); 2824 2825 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len) 2826 { 2827 return -EOPNOTSUPP; 2828 } 2829 EXPORT_SYMBOL(sock_no_sendmsg_locked); 2830 2831 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len, 2832 int flags) 2833 { 2834 return -EOPNOTSUPP; 2835 } 2836 EXPORT_SYMBOL(sock_no_recvmsg); 2837 2838 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2839 { 2840 /* Mirror missing mmap method error code */ 2841 return -ENODEV; 2842 } 2843 EXPORT_SYMBOL(sock_no_mmap); 2844 2845 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2846 { 2847 ssize_t res; 2848 struct msghdr msg = {.msg_flags = flags}; 2849 struct kvec iov; 2850 char *kaddr = kmap(page); 2851 iov.iov_base = kaddr + offset; 2852 iov.iov_len = size; 2853 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2854 kunmap(page); 2855 return res; 2856 } 2857 EXPORT_SYMBOL(sock_no_sendpage); 2858 2859 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page, 2860 int offset, size_t size, int flags) 2861 { 2862 ssize_t res; 2863 struct msghdr msg = {.msg_flags = flags}; 2864 struct kvec iov; 2865 char *kaddr = kmap(page); 2866 2867 iov.iov_base = kaddr + offset; 2868 iov.iov_len = size; 2869 res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size); 2870 kunmap(page); 2871 return res; 2872 } 2873 EXPORT_SYMBOL(sock_no_sendpage_locked); 2874 2875 /* 2876 * Default Socket Callbacks 2877 */ 2878 2879 static void sock_def_wakeup(struct sock *sk) 2880 { 2881 struct socket_wq *wq; 2882 2883 rcu_read_lock(); 2884 wq = rcu_dereference(sk->sk_wq); 2885 if (skwq_has_sleeper(wq)) 2886 wake_up_interruptible_all(&wq->wait); 2887 rcu_read_unlock(); 2888 } 2889 2890 static void sock_def_error_report(struct sock *sk) 2891 { 2892 struct socket_wq *wq; 2893 2894 rcu_read_lock(); 2895 wq = rcu_dereference(sk->sk_wq); 2896 if (skwq_has_sleeper(wq)) 2897 wake_up_interruptible_poll(&wq->wait, EPOLLERR); 2898 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2899 rcu_read_unlock(); 2900 } 2901 2902 void sock_def_readable(struct sock *sk) 2903 { 2904 struct socket_wq *wq; 2905 2906 rcu_read_lock(); 2907 wq = rcu_dereference(sk->sk_wq); 2908 if (skwq_has_sleeper(wq)) 2909 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI | 2910 EPOLLRDNORM | EPOLLRDBAND); 2911 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2912 rcu_read_unlock(); 2913 } 2914 2915 static void sock_def_write_space(struct sock *sk) 2916 { 2917 struct socket_wq *wq; 2918 2919 rcu_read_lock(); 2920 2921 /* Do not wake up a writer until he can make "significant" 2922 * progress. --DaveM 2923 */ 2924 if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= READ_ONCE(sk->sk_sndbuf)) { 2925 wq = rcu_dereference(sk->sk_wq); 2926 if (skwq_has_sleeper(wq)) 2927 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT | 2928 EPOLLWRNORM | EPOLLWRBAND); 2929 2930 /* Should agree with poll, otherwise some programs break */ 2931 if (sock_writeable(sk)) 2932 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2933 } 2934 2935 rcu_read_unlock(); 2936 } 2937 2938 static void sock_def_destruct(struct sock *sk) 2939 { 2940 } 2941 2942 void sk_send_sigurg(struct sock *sk) 2943 { 2944 if (sk->sk_socket && sk->sk_socket->file) 2945 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2946 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2947 } 2948 EXPORT_SYMBOL(sk_send_sigurg); 2949 2950 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2951 unsigned long expires) 2952 { 2953 if (!mod_timer(timer, expires)) 2954 sock_hold(sk); 2955 } 2956 EXPORT_SYMBOL(sk_reset_timer); 2957 2958 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2959 { 2960 if (del_timer(timer)) 2961 __sock_put(sk); 2962 } 2963 EXPORT_SYMBOL(sk_stop_timer); 2964 2965 void sock_init_data(struct socket *sock, struct sock *sk) 2966 { 2967 sk_init_common(sk); 2968 sk->sk_send_head = NULL; 2969 2970 timer_setup(&sk->sk_timer, NULL, 0); 2971 2972 sk->sk_allocation = GFP_KERNEL; 2973 sk->sk_rcvbuf = sysctl_rmem_default; 2974 sk->sk_sndbuf = sysctl_wmem_default; 2975 sk->sk_state = TCP_CLOSE; 2976 sk_set_socket(sk, sock); 2977 2978 sock_set_flag(sk, SOCK_ZAPPED); 2979 2980 if (sock) { 2981 sk->sk_type = sock->type; 2982 RCU_INIT_POINTER(sk->sk_wq, &sock->wq); 2983 sock->sk = sk; 2984 sk->sk_uid = SOCK_INODE(sock)->i_uid; 2985 } else { 2986 RCU_INIT_POINTER(sk->sk_wq, NULL); 2987 sk->sk_uid = make_kuid(sock_net(sk)->user_ns, 0); 2988 } 2989 2990 rwlock_init(&sk->sk_callback_lock); 2991 if (sk->sk_kern_sock) 2992 lockdep_set_class_and_name( 2993 &sk->sk_callback_lock, 2994 af_kern_callback_keys + sk->sk_family, 2995 af_family_kern_clock_key_strings[sk->sk_family]); 2996 else 2997 lockdep_set_class_and_name( 2998 &sk->sk_callback_lock, 2999 af_callback_keys + sk->sk_family, 3000 af_family_clock_key_strings[sk->sk_family]); 3001 3002 sk->sk_state_change = sock_def_wakeup; 3003 sk->sk_data_ready = sock_def_readable; 3004 sk->sk_write_space = sock_def_write_space; 3005 sk->sk_error_report = sock_def_error_report; 3006 sk->sk_destruct = sock_def_destruct; 3007 3008 sk->sk_frag.page = NULL; 3009 sk->sk_frag.offset = 0; 3010 sk->sk_peek_off = -1; 3011 3012 sk->sk_peer_pid = NULL; 3013 sk->sk_peer_cred = NULL; 3014 sk->sk_write_pending = 0; 3015 sk->sk_rcvlowat = 1; 3016 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 3017 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 3018 3019 sk->sk_stamp = SK_DEFAULT_STAMP; 3020 #if BITS_PER_LONG==32 3021 seqlock_init(&sk->sk_stamp_seq); 3022 #endif 3023 atomic_set(&sk->sk_zckey, 0); 3024 3025 #ifdef CONFIG_NET_RX_BUSY_POLL 3026 sk->sk_napi_id = 0; 3027 sk->sk_ll_usec = sysctl_net_busy_read; 3028 #endif 3029 3030 sk->sk_max_pacing_rate = ~0UL; 3031 sk->sk_pacing_rate = ~0UL; 3032 WRITE_ONCE(sk->sk_pacing_shift, 10); 3033 sk->sk_incoming_cpu = -1; 3034 3035 sk_rx_queue_clear(sk); 3036 /* 3037 * Before updating sk_refcnt, we must commit prior changes to memory 3038 * (Documentation/RCU/rculist_nulls.txt for details) 3039 */ 3040 smp_wmb(); 3041 refcount_set(&sk->sk_refcnt, 1); 3042 atomic_set(&sk->sk_drops, 0); 3043 } 3044 EXPORT_SYMBOL(sock_init_data); 3045 3046 void lock_sock_nested(struct sock *sk, int subclass) 3047 { 3048 might_sleep(); 3049 spin_lock_bh(&sk->sk_lock.slock); 3050 if (sk->sk_lock.owned) 3051 __lock_sock(sk); 3052 sk->sk_lock.owned = 1; 3053 spin_unlock(&sk->sk_lock.slock); 3054 /* 3055 * The sk_lock has mutex_lock() semantics here: 3056 */ 3057 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 3058 local_bh_enable(); 3059 } 3060 EXPORT_SYMBOL(lock_sock_nested); 3061 3062 void release_sock(struct sock *sk) 3063 { 3064 spin_lock_bh(&sk->sk_lock.slock); 3065 if (sk->sk_backlog.tail) 3066 __release_sock(sk); 3067 3068 /* Warning : release_cb() might need to release sk ownership, 3069 * ie call sock_release_ownership(sk) before us. 3070 */ 3071 if (sk->sk_prot->release_cb) 3072 sk->sk_prot->release_cb(sk); 3073 3074 sock_release_ownership(sk); 3075 if (waitqueue_active(&sk->sk_lock.wq)) 3076 wake_up(&sk->sk_lock.wq); 3077 spin_unlock_bh(&sk->sk_lock.slock); 3078 } 3079 EXPORT_SYMBOL(release_sock); 3080 3081 /** 3082 * lock_sock_fast - fast version of lock_sock 3083 * @sk: socket 3084 * 3085 * This version should be used for very small section, where process wont block 3086 * return false if fast path is taken: 3087 * 3088 * sk_lock.slock locked, owned = 0, BH disabled 3089 * 3090 * return true if slow path is taken: 3091 * 3092 * sk_lock.slock unlocked, owned = 1, BH enabled 3093 */ 3094 bool lock_sock_fast(struct sock *sk) 3095 { 3096 might_sleep(); 3097 spin_lock_bh(&sk->sk_lock.slock); 3098 3099 if (!sk->sk_lock.owned) 3100 /* 3101 * Note : We must disable BH 3102 */ 3103 return false; 3104 3105 __lock_sock(sk); 3106 sk->sk_lock.owned = 1; 3107 spin_unlock(&sk->sk_lock.slock); 3108 /* 3109 * The sk_lock has mutex_lock() semantics here: 3110 */ 3111 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 3112 local_bh_enable(); 3113 return true; 3114 } 3115 EXPORT_SYMBOL(lock_sock_fast); 3116 3117 int sock_gettstamp(struct socket *sock, void __user *userstamp, 3118 bool timeval, bool time32) 3119 { 3120 struct sock *sk = sock->sk; 3121 struct timespec64 ts; 3122 3123 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 3124 ts = ktime_to_timespec64(sock_read_timestamp(sk)); 3125 if (ts.tv_sec == -1) 3126 return -ENOENT; 3127 if (ts.tv_sec == 0) { 3128 ktime_t kt = ktime_get_real(); 3129 sock_write_timestamp(sk, kt); 3130 ts = ktime_to_timespec64(kt); 3131 } 3132 3133 if (timeval) 3134 ts.tv_nsec /= 1000; 3135 3136 #ifdef CONFIG_COMPAT_32BIT_TIME 3137 if (time32) 3138 return put_old_timespec32(&ts, userstamp); 3139 #endif 3140 #ifdef CONFIG_SPARC64 3141 /* beware of padding in sparc64 timeval */ 3142 if (timeval && !in_compat_syscall()) { 3143 struct __kernel_old_timeval __user tv = { 3144 .tv_sec = ts.tv_sec, 3145 .tv_usec = ts.tv_nsec, 3146 }; 3147 if (copy_to_user(userstamp, &tv, sizeof(tv))) 3148 return -EFAULT; 3149 return 0; 3150 } 3151 #endif 3152 return put_timespec64(&ts, userstamp); 3153 } 3154 EXPORT_SYMBOL(sock_gettstamp); 3155 3156 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag) 3157 { 3158 if (!sock_flag(sk, flag)) { 3159 unsigned long previous_flags = sk->sk_flags; 3160 3161 sock_set_flag(sk, flag); 3162 /* 3163 * we just set one of the two flags which require net 3164 * time stamping, but time stamping might have been on 3165 * already because of the other one 3166 */ 3167 if (sock_needs_netstamp(sk) && 3168 !(previous_flags & SK_FLAGS_TIMESTAMP)) 3169 net_enable_timestamp(); 3170 } 3171 } 3172 3173 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 3174 int level, int type) 3175 { 3176 struct sock_exterr_skb *serr; 3177 struct sk_buff *skb; 3178 int copied, err; 3179 3180 err = -EAGAIN; 3181 skb = sock_dequeue_err_skb(sk); 3182 if (skb == NULL) 3183 goto out; 3184 3185 copied = skb->len; 3186 if (copied > len) { 3187 msg->msg_flags |= MSG_TRUNC; 3188 copied = len; 3189 } 3190 err = skb_copy_datagram_msg(skb, 0, msg, copied); 3191 if (err) 3192 goto out_free_skb; 3193 3194 sock_recv_timestamp(msg, sk, skb); 3195 3196 serr = SKB_EXT_ERR(skb); 3197 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 3198 3199 msg->msg_flags |= MSG_ERRQUEUE; 3200 err = copied; 3201 3202 out_free_skb: 3203 kfree_skb(skb); 3204 out: 3205 return err; 3206 } 3207 EXPORT_SYMBOL(sock_recv_errqueue); 3208 3209 /* 3210 * Get a socket option on an socket. 3211 * 3212 * FIX: POSIX 1003.1g is very ambiguous here. It states that 3213 * asynchronous errors should be reported by getsockopt. We assume 3214 * this means if you specify SO_ERROR (otherwise whats the point of it). 3215 */ 3216 int sock_common_getsockopt(struct socket *sock, int level, int optname, 3217 char __user *optval, int __user *optlen) 3218 { 3219 struct sock *sk = sock->sk; 3220 3221 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 3222 } 3223 EXPORT_SYMBOL(sock_common_getsockopt); 3224 3225 #ifdef CONFIG_COMPAT 3226 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 3227 char __user *optval, int __user *optlen) 3228 { 3229 struct sock *sk = sock->sk; 3230 3231 if (sk->sk_prot->compat_getsockopt != NULL) 3232 return sk->sk_prot->compat_getsockopt(sk, level, optname, 3233 optval, optlen); 3234 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 3235 } 3236 EXPORT_SYMBOL(compat_sock_common_getsockopt); 3237 #endif 3238 3239 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 3240 int flags) 3241 { 3242 struct sock *sk = sock->sk; 3243 int addr_len = 0; 3244 int err; 3245 3246 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, 3247 flags & ~MSG_DONTWAIT, &addr_len); 3248 if (err >= 0) 3249 msg->msg_namelen = addr_len; 3250 return err; 3251 } 3252 EXPORT_SYMBOL(sock_common_recvmsg); 3253 3254 /* 3255 * Set socket options on an inet socket. 3256 */ 3257 int sock_common_setsockopt(struct socket *sock, int level, int optname, 3258 char __user *optval, unsigned int optlen) 3259 { 3260 struct sock *sk = sock->sk; 3261 3262 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 3263 } 3264 EXPORT_SYMBOL(sock_common_setsockopt); 3265 3266 #ifdef CONFIG_COMPAT 3267 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 3268 char __user *optval, unsigned int optlen) 3269 { 3270 struct sock *sk = sock->sk; 3271 3272 if (sk->sk_prot->compat_setsockopt != NULL) 3273 return sk->sk_prot->compat_setsockopt(sk, level, optname, 3274 optval, optlen); 3275 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 3276 } 3277 EXPORT_SYMBOL(compat_sock_common_setsockopt); 3278 #endif 3279 3280 void sk_common_release(struct sock *sk) 3281 { 3282 if (sk->sk_prot->destroy) 3283 sk->sk_prot->destroy(sk); 3284 3285 /* 3286 * Observation: when sock_common_release is called, processes have 3287 * no access to socket. But net still has. 3288 * Step one, detach it from networking: 3289 * 3290 * A. Remove from hash tables. 3291 */ 3292 3293 sk->sk_prot->unhash(sk); 3294 3295 /* 3296 * In this point socket cannot receive new packets, but it is possible 3297 * that some packets are in flight because some CPU runs receiver and 3298 * did hash table lookup before we unhashed socket. They will achieve 3299 * receive queue and will be purged by socket destructor. 3300 * 3301 * Also we still have packets pending on receive queue and probably, 3302 * our own packets waiting in device queues. sock_destroy will drain 3303 * receive queue, but transmitted packets will delay socket destruction 3304 * until the last reference will be released. 3305 */ 3306 3307 sock_orphan(sk); 3308 3309 xfrm_sk_free_policy(sk); 3310 3311 sk_refcnt_debug_release(sk); 3312 3313 sock_put(sk); 3314 } 3315 EXPORT_SYMBOL(sk_common_release); 3316 3317 void sk_get_meminfo(const struct sock *sk, u32 *mem) 3318 { 3319 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS); 3320 3321 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk); 3322 mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf); 3323 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk); 3324 mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf); 3325 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc; 3326 mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued); 3327 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc); 3328 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len); 3329 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops); 3330 } 3331 3332 #ifdef CONFIG_PROC_FS 3333 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 3334 struct prot_inuse { 3335 int val[PROTO_INUSE_NR]; 3336 }; 3337 3338 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 3339 3340 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 3341 { 3342 __this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val); 3343 } 3344 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 3345 3346 int sock_prot_inuse_get(struct net *net, struct proto *prot) 3347 { 3348 int cpu, idx = prot->inuse_idx; 3349 int res = 0; 3350 3351 for_each_possible_cpu(cpu) 3352 res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx]; 3353 3354 return res >= 0 ? res : 0; 3355 } 3356 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 3357 3358 static void sock_inuse_add(struct net *net, int val) 3359 { 3360 this_cpu_add(*net->core.sock_inuse, val); 3361 } 3362 3363 int sock_inuse_get(struct net *net) 3364 { 3365 int cpu, res = 0; 3366 3367 for_each_possible_cpu(cpu) 3368 res += *per_cpu_ptr(net->core.sock_inuse, cpu); 3369 3370 return res; 3371 } 3372 3373 EXPORT_SYMBOL_GPL(sock_inuse_get); 3374 3375 static int __net_init sock_inuse_init_net(struct net *net) 3376 { 3377 net->core.prot_inuse = alloc_percpu(struct prot_inuse); 3378 if (net->core.prot_inuse == NULL) 3379 return -ENOMEM; 3380 3381 net->core.sock_inuse = alloc_percpu(int); 3382 if (net->core.sock_inuse == NULL) 3383 goto out; 3384 3385 return 0; 3386 3387 out: 3388 free_percpu(net->core.prot_inuse); 3389 return -ENOMEM; 3390 } 3391 3392 static void __net_exit sock_inuse_exit_net(struct net *net) 3393 { 3394 free_percpu(net->core.prot_inuse); 3395 free_percpu(net->core.sock_inuse); 3396 } 3397 3398 static struct pernet_operations net_inuse_ops = { 3399 .init = sock_inuse_init_net, 3400 .exit = sock_inuse_exit_net, 3401 }; 3402 3403 static __init int net_inuse_init(void) 3404 { 3405 if (register_pernet_subsys(&net_inuse_ops)) 3406 panic("Cannot initialize net inuse counters"); 3407 3408 return 0; 3409 } 3410 3411 core_initcall(net_inuse_init); 3412 3413 static int assign_proto_idx(struct proto *prot) 3414 { 3415 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 3416 3417 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 3418 pr_err("PROTO_INUSE_NR exhausted\n"); 3419 return -ENOSPC; 3420 } 3421 3422 set_bit(prot->inuse_idx, proto_inuse_idx); 3423 return 0; 3424 } 3425 3426 static void release_proto_idx(struct proto *prot) 3427 { 3428 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 3429 clear_bit(prot->inuse_idx, proto_inuse_idx); 3430 } 3431 #else 3432 static inline int assign_proto_idx(struct proto *prot) 3433 { 3434 return 0; 3435 } 3436 3437 static inline void release_proto_idx(struct proto *prot) 3438 { 3439 } 3440 3441 static void sock_inuse_add(struct net *net, int val) 3442 { 3443 } 3444 #endif 3445 3446 static void req_prot_cleanup(struct request_sock_ops *rsk_prot) 3447 { 3448 if (!rsk_prot) 3449 return; 3450 kfree(rsk_prot->slab_name); 3451 rsk_prot->slab_name = NULL; 3452 kmem_cache_destroy(rsk_prot->slab); 3453 rsk_prot->slab = NULL; 3454 } 3455 3456 static int req_prot_init(const struct proto *prot) 3457 { 3458 struct request_sock_ops *rsk_prot = prot->rsk_prot; 3459 3460 if (!rsk_prot) 3461 return 0; 3462 3463 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", 3464 prot->name); 3465 if (!rsk_prot->slab_name) 3466 return -ENOMEM; 3467 3468 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name, 3469 rsk_prot->obj_size, 0, 3470 SLAB_ACCOUNT | prot->slab_flags, 3471 NULL); 3472 3473 if (!rsk_prot->slab) { 3474 pr_crit("%s: Can't create request sock SLAB cache!\n", 3475 prot->name); 3476 return -ENOMEM; 3477 } 3478 return 0; 3479 } 3480 3481 int proto_register(struct proto *prot, int alloc_slab) 3482 { 3483 int ret = -ENOBUFS; 3484 3485 if (alloc_slab) { 3486 prot->slab = kmem_cache_create_usercopy(prot->name, 3487 prot->obj_size, 0, 3488 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT | 3489 prot->slab_flags, 3490 prot->useroffset, prot->usersize, 3491 NULL); 3492 3493 if (prot->slab == NULL) { 3494 pr_crit("%s: Can't create sock SLAB cache!\n", 3495 prot->name); 3496 goto out; 3497 } 3498 3499 if (req_prot_init(prot)) 3500 goto out_free_request_sock_slab; 3501 3502 if (prot->twsk_prot != NULL) { 3503 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 3504 3505 if (prot->twsk_prot->twsk_slab_name == NULL) 3506 goto out_free_request_sock_slab; 3507 3508 prot->twsk_prot->twsk_slab = 3509 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 3510 prot->twsk_prot->twsk_obj_size, 3511 0, 3512 SLAB_ACCOUNT | 3513 prot->slab_flags, 3514 NULL); 3515 if (prot->twsk_prot->twsk_slab == NULL) 3516 goto out_free_timewait_sock_slab_name; 3517 } 3518 } 3519 3520 mutex_lock(&proto_list_mutex); 3521 ret = assign_proto_idx(prot); 3522 if (ret) { 3523 mutex_unlock(&proto_list_mutex); 3524 goto out_free_timewait_sock_slab_name; 3525 } 3526 list_add(&prot->node, &proto_list); 3527 mutex_unlock(&proto_list_mutex); 3528 return ret; 3529 3530 out_free_timewait_sock_slab_name: 3531 if (alloc_slab && prot->twsk_prot) 3532 kfree(prot->twsk_prot->twsk_slab_name); 3533 out_free_request_sock_slab: 3534 if (alloc_slab) { 3535 req_prot_cleanup(prot->rsk_prot); 3536 3537 kmem_cache_destroy(prot->slab); 3538 prot->slab = NULL; 3539 } 3540 out: 3541 return ret; 3542 } 3543 EXPORT_SYMBOL(proto_register); 3544 3545 void proto_unregister(struct proto *prot) 3546 { 3547 mutex_lock(&proto_list_mutex); 3548 release_proto_idx(prot); 3549 list_del(&prot->node); 3550 mutex_unlock(&proto_list_mutex); 3551 3552 kmem_cache_destroy(prot->slab); 3553 prot->slab = NULL; 3554 3555 req_prot_cleanup(prot->rsk_prot); 3556 3557 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 3558 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 3559 kfree(prot->twsk_prot->twsk_slab_name); 3560 prot->twsk_prot->twsk_slab = NULL; 3561 } 3562 } 3563 EXPORT_SYMBOL(proto_unregister); 3564 3565 int sock_load_diag_module(int family, int protocol) 3566 { 3567 if (!protocol) { 3568 if (!sock_is_registered(family)) 3569 return -ENOENT; 3570 3571 return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK, 3572 NETLINK_SOCK_DIAG, family); 3573 } 3574 3575 #ifdef CONFIG_INET 3576 if (family == AF_INET && 3577 protocol != IPPROTO_RAW && 3578 !rcu_access_pointer(inet_protos[protocol])) 3579 return -ENOENT; 3580 #endif 3581 3582 return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK, 3583 NETLINK_SOCK_DIAG, family, protocol); 3584 } 3585 EXPORT_SYMBOL(sock_load_diag_module); 3586 3587 #ifdef CONFIG_PROC_FS 3588 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 3589 __acquires(proto_list_mutex) 3590 { 3591 mutex_lock(&proto_list_mutex); 3592 return seq_list_start_head(&proto_list, *pos); 3593 } 3594 3595 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 3596 { 3597 return seq_list_next(v, &proto_list, pos); 3598 } 3599 3600 static void proto_seq_stop(struct seq_file *seq, void *v) 3601 __releases(proto_list_mutex) 3602 { 3603 mutex_unlock(&proto_list_mutex); 3604 } 3605 3606 static char proto_method_implemented(const void *method) 3607 { 3608 return method == NULL ? 'n' : 'y'; 3609 } 3610 static long sock_prot_memory_allocated(struct proto *proto) 3611 { 3612 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 3613 } 3614 3615 static const char *sock_prot_memory_pressure(struct proto *proto) 3616 { 3617 return proto->memory_pressure != NULL ? 3618 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 3619 } 3620 3621 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 3622 { 3623 3624 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 3625 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 3626 proto->name, 3627 proto->obj_size, 3628 sock_prot_inuse_get(seq_file_net(seq), proto), 3629 sock_prot_memory_allocated(proto), 3630 sock_prot_memory_pressure(proto), 3631 proto->max_header, 3632 proto->slab == NULL ? "no" : "yes", 3633 module_name(proto->owner), 3634 proto_method_implemented(proto->close), 3635 proto_method_implemented(proto->connect), 3636 proto_method_implemented(proto->disconnect), 3637 proto_method_implemented(proto->accept), 3638 proto_method_implemented(proto->ioctl), 3639 proto_method_implemented(proto->init), 3640 proto_method_implemented(proto->destroy), 3641 proto_method_implemented(proto->shutdown), 3642 proto_method_implemented(proto->setsockopt), 3643 proto_method_implemented(proto->getsockopt), 3644 proto_method_implemented(proto->sendmsg), 3645 proto_method_implemented(proto->recvmsg), 3646 proto_method_implemented(proto->sendpage), 3647 proto_method_implemented(proto->bind), 3648 proto_method_implemented(proto->backlog_rcv), 3649 proto_method_implemented(proto->hash), 3650 proto_method_implemented(proto->unhash), 3651 proto_method_implemented(proto->get_port), 3652 proto_method_implemented(proto->enter_memory_pressure)); 3653 } 3654 3655 static int proto_seq_show(struct seq_file *seq, void *v) 3656 { 3657 if (v == &proto_list) 3658 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 3659 "protocol", 3660 "size", 3661 "sockets", 3662 "memory", 3663 "press", 3664 "maxhdr", 3665 "slab", 3666 "module", 3667 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 3668 else 3669 proto_seq_printf(seq, list_entry(v, struct proto, node)); 3670 return 0; 3671 } 3672 3673 static const struct seq_operations proto_seq_ops = { 3674 .start = proto_seq_start, 3675 .next = proto_seq_next, 3676 .stop = proto_seq_stop, 3677 .show = proto_seq_show, 3678 }; 3679 3680 static __net_init int proto_init_net(struct net *net) 3681 { 3682 if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops, 3683 sizeof(struct seq_net_private))) 3684 return -ENOMEM; 3685 3686 return 0; 3687 } 3688 3689 static __net_exit void proto_exit_net(struct net *net) 3690 { 3691 remove_proc_entry("protocols", net->proc_net); 3692 } 3693 3694 3695 static __net_initdata struct pernet_operations proto_net_ops = { 3696 .init = proto_init_net, 3697 .exit = proto_exit_net, 3698 }; 3699 3700 static int __init proto_init(void) 3701 { 3702 return register_pernet_subsys(&proto_net_ops); 3703 } 3704 3705 subsys_initcall(proto_init); 3706 3707 #endif /* PROC_FS */ 3708 3709 #ifdef CONFIG_NET_RX_BUSY_POLL 3710 bool sk_busy_loop_end(void *p, unsigned long start_time) 3711 { 3712 struct sock *sk = p; 3713 3714 return !skb_queue_empty_lockless(&sk->sk_receive_queue) || 3715 sk_busy_loop_timeout(sk, start_time); 3716 } 3717 EXPORT_SYMBOL(sk_busy_loop_end); 3718 #endif /* CONFIG_NET_RX_BUSY_POLL */ 3719 3720 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len) 3721 { 3722 if (!sk->sk_prot->bind_add) 3723 return -EOPNOTSUPP; 3724 return sk->sk_prot->bind_add(sk, addr, addr_len); 3725 } 3726 EXPORT_SYMBOL(sock_bind_add); 3727