1 /* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * Generic socket support routines. Memory allocators, socket lock/release 7 * handler for protocols to use and generic option handler. 8 * 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 * This program is free software; you can redistribute it and/or 87 * modify it under the terms of the GNU General Public License 88 * as published by the Free Software Foundation; either version 89 * 2 of the License, or (at your option) any later version. 90 */ 91 92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 93 94 #include <linux/capability.h> 95 #include <linux/errno.h> 96 #include <linux/errqueue.h> 97 #include <linux/types.h> 98 #include <linux/socket.h> 99 #include <linux/in.h> 100 #include <linux/kernel.h> 101 #include <linux/module.h> 102 #include <linux/proc_fs.h> 103 #include <linux/seq_file.h> 104 #include <linux/sched.h> 105 #include <linux/timer.h> 106 #include <linux/string.h> 107 #include <linux/sockios.h> 108 #include <linux/net.h> 109 #include <linux/mm.h> 110 #include <linux/slab.h> 111 #include <linux/interrupt.h> 112 #include <linux/poll.h> 113 #include <linux/tcp.h> 114 #include <linux/init.h> 115 #include <linux/highmem.h> 116 #include <linux/user_namespace.h> 117 #include <linux/static_key.h> 118 #include <linux/memcontrol.h> 119 #include <linux/prefetch.h> 120 121 #include <asm/uaccess.h> 122 123 #include <linux/netdevice.h> 124 #include <net/protocol.h> 125 #include <linux/skbuff.h> 126 #include <net/net_namespace.h> 127 #include <net/request_sock.h> 128 #include <net/sock.h> 129 #include <linux/net_tstamp.h> 130 #include <net/xfrm.h> 131 #include <linux/ipsec.h> 132 #include <net/cls_cgroup.h> 133 #include <net/netprio_cgroup.h> 134 #include <linux/sock_diag.h> 135 136 #include <linux/filter.h> 137 #include <net/sock_reuseport.h> 138 139 #include <trace/events/sock.h> 140 141 #ifdef CONFIG_INET 142 #include <net/tcp.h> 143 #endif 144 145 #include <net/busy_poll.h> 146 147 static DEFINE_MUTEX(proto_list_mutex); 148 static LIST_HEAD(proto_list); 149 150 /** 151 * sk_ns_capable - General socket capability test 152 * @sk: Socket to use a capability on or through 153 * @user_ns: The user namespace of the capability to use 154 * @cap: The capability to use 155 * 156 * Test to see if the opener of the socket had when the socket was 157 * created and the current process has the capability @cap in the user 158 * namespace @user_ns. 159 */ 160 bool sk_ns_capable(const struct sock *sk, 161 struct user_namespace *user_ns, int cap) 162 { 163 return file_ns_capable(sk->sk_socket->file, user_ns, cap) && 164 ns_capable(user_ns, cap); 165 } 166 EXPORT_SYMBOL(sk_ns_capable); 167 168 /** 169 * sk_capable - Socket global capability test 170 * @sk: Socket to use a capability on or through 171 * @cap: The global capability to use 172 * 173 * Test to see if the opener of the socket had when the socket was 174 * created and the current process has the capability @cap in all user 175 * namespaces. 176 */ 177 bool sk_capable(const struct sock *sk, int cap) 178 { 179 return sk_ns_capable(sk, &init_user_ns, cap); 180 } 181 EXPORT_SYMBOL(sk_capable); 182 183 /** 184 * sk_net_capable - Network namespace socket capability test 185 * @sk: Socket to use a capability on or through 186 * @cap: The capability to use 187 * 188 * Test to see if the opener of the socket had when the socket was created 189 * and the current process has the capability @cap over the network namespace 190 * the socket is a member of. 191 */ 192 bool sk_net_capable(const struct sock *sk, int cap) 193 { 194 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap); 195 } 196 EXPORT_SYMBOL(sk_net_capable); 197 198 /* 199 * Each address family might have different locking rules, so we have 200 * one slock key per address family: 201 */ 202 static struct lock_class_key af_family_keys[AF_MAX]; 203 static struct lock_class_key af_family_slock_keys[AF_MAX]; 204 205 /* 206 * Make lock validator output more readable. (we pre-construct these 207 * strings build-time, so that runtime initialization of socket 208 * locks is fast): 209 */ 210 static const char *const af_family_key_strings[AF_MAX+1] = { 211 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" , 212 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK", 213 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" , 214 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" , 215 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" , 216 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" , 217 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" , 218 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" , 219 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" , 220 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" , 221 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" , 222 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" , 223 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" , 224 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_KCM" , 225 "sk_lock-AF_MAX" 226 }; 227 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 228 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" , 229 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK", 230 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" , 231 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" , 232 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" , 233 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" , 234 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" , 235 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" , 236 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" , 237 "slock-27" , "slock-28" , "slock-AF_CAN" , 238 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" , 239 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" , 240 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" , 241 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_KCM" , 242 "slock-AF_MAX" 243 }; 244 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 245 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" , 246 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK", 247 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" , 248 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" , 249 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" , 250 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" , 251 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" , 252 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" , 253 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" , 254 "clock-27" , "clock-28" , "clock-AF_CAN" , 255 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" , 256 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" , 257 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" , 258 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_KCM" , 259 "clock-AF_MAX" 260 }; 261 262 /* 263 * sk_callback_lock locking rules are per-address-family, 264 * so split the lock classes by using a per-AF key: 265 */ 266 static struct lock_class_key af_callback_keys[AF_MAX]; 267 268 /* Take into consideration the size of the struct sk_buff overhead in the 269 * determination of these values, since that is non-constant across 270 * platforms. This makes socket queueing behavior and performance 271 * not depend upon such differences. 272 */ 273 #define _SK_MEM_PACKETS 256 274 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 275 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 276 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 277 278 /* Run time adjustable parameters. */ 279 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 280 EXPORT_SYMBOL(sysctl_wmem_max); 281 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 282 EXPORT_SYMBOL(sysctl_rmem_max); 283 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 284 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 285 286 /* Maximal space eaten by iovec or ancillary data plus some space */ 287 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); 288 EXPORT_SYMBOL(sysctl_optmem_max); 289 290 int sysctl_tstamp_allow_data __read_mostly = 1; 291 292 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE; 293 EXPORT_SYMBOL_GPL(memalloc_socks); 294 295 /** 296 * sk_set_memalloc - sets %SOCK_MEMALLOC 297 * @sk: socket to set it on 298 * 299 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 300 * It's the responsibility of the admin to adjust min_free_kbytes 301 * to meet the requirements 302 */ 303 void sk_set_memalloc(struct sock *sk) 304 { 305 sock_set_flag(sk, SOCK_MEMALLOC); 306 sk->sk_allocation |= __GFP_MEMALLOC; 307 static_key_slow_inc(&memalloc_socks); 308 } 309 EXPORT_SYMBOL_GPL(sk_set_memalloc); 310 311 void sk_clear_memalloc(struct sock *sk) 312 { 313 sock_reset_flag(sk, SOCK_MEMALLOC); 314 sk->sk_allocation &= ~__GFP_MEMALLOC; 315 static_key_slow_dec(&memalloc_socks); 316 317 /* 318 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 319 * progress of swapping. SOCK_MEMALLOC may be cleared while 320 * it has rmem allocations due to the last swapfile being deactivated 321 * but there is a risk that the socket is unusable due to exceeding 322 * the rmem limits. Reclaim the reserves and obey rmem limits again. 323 */ 324 sk_mem_reclaim(sk); 325 } 326 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 327 328 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 329 { 330 int ret; 331 unsigned long pflags = current->flags; 332 333 /* these should have been dropped before queueing */ 334 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 335 336 current->flags |= PF_MEMALLOC; 337 ret = sk->sk_backlog_rcv(sk, skb); 338 tsk_restore_flags(current, pflags, PF_MEMALLOC); 339 340 return ret; 341 } 342 EXPORT_SYMBOL(__sk_backlog_rcv); 343 344 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen) 345 { 346 struct timeval tv; 347 348 if (optlen < sizeof(tv)) 349 return -EINVAL; 350 if (copy_from_user(&tv, optval, sizeof(tv))) 351 return -EFAULT; 352 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 353 return -EDOM; 354 355 if (tv.tv_sec < 0) { 356 static int warned __read_mostly; 357 358 *timeo_p = 0; 359 if (warned < 10 && net_ratelimit()) { 360 warned++; 361 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 362 __func__, current->comm, task_pid_nr(current)); 363 } 364 return 0; 365 } 366 *timeo_p = MAX_SCHEDULE_TIMEOUT; 367 if (tv.tv_sec == 0 && tv.tv_usec == 0) 368 return 0; 369 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1)) 370 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ); 371 return 0; 372 } 373 374 static void sock_warn_obsolete_bsdism(const char *name) 375 { 376 static int warned; 377 static char warncomm[TASK_COMM_LEN]; 378 if (strcmp(warncomm, current->comm) && warned < 5) { 379 strcpy(warncomm, current->comm); 380 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", 381 warncomm, name); 382 warned++; 383 } 384 } 385 386 static bool sock_needs_netstamp(const struct sock *sk) 387 { 388 switch (sk->sk_family) { 389 case AF_UNSPEC: 390 case AF_UNIX: 391 return false; 392 default: 393 return true; 394 } 395 } 396 397 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 398 { 399 if (sk->sk_flags & flags) { 400 sk->sk_flags &= ~flags; 401 if (sock_needs_netstamp(sk) && 402 !(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 403 net_disable_timestamp(); 404 } 405 } 406 407 408 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 409 { 410 unsigned long flags; 411 struct sk_buff_head *list = &sk->sk_receive_queue; 412 413 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 414 atomic_inc(&sk->sk_drops); 415 trace_sock_rcvqueue_full(sk, skb); 416 return -ENOMEM; 417 } 418 419 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 420 atomic_inc(&sk->sk_drops); 421 return -ENOBUFS; 422 } 423 424 skb->dev = NULL; 425 skb_set_owner_r(skb, sk); 426 427 /* we escape from rcu protected region, make sure we dont leak 428 * a norefcounted dst 429 */ 430 skb_dst_force(skb); 431 432 spin_lock_irqsave(&list->lock, flags); 433 sock_skb_set_dropcount(sk, skb); 434 __skb_queue_tail(list, skb); 435 spin_unlock_irqrestore(&list->lock, flags); 436 437 if (!sock_flag(sk, SOCK_DEAD)) 438 sk->sk_data_ready(sk); 439 return 0; 440 } 441 EXPORT_SYMBOL(__sock_queue_rcv_skb); 442 443 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 444 { 445 int err; 446 447 err = sk_filter(sk, skb); 448 if (err) 449 return err; 450 451 return __sock_queue_rcv_skb(sk, skb); 452 } 453 EXPORT_SYMBOL(sock_queue_rcv_skb); 454 455 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, 456 const int nested, unsigned int trim_cap) 457 { 458 int rc = NET_RX_SUCCESS; 459 460 if (sk_filter_trim_cap(sk, skb, trim_cap)) 461 goto discard_and_relse; 462 463 skb->dev = NULL; 464 465 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 466 atomic_inc(&sk->sk_drops); 467 goto discard_and_relse; 468 } 469 if (nested) 470 bh_lock_sock_nested(sk); 471 else 472 bh_lock_sock(sk); 473 if (!sock_owned_by_user(sk)) { 474 /* 475 * trylock + unlock semantics: 476 */ 477 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 478 479 rc = sk_backlog_rcv(sk, skb); 480 481 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 482 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 483 bh_unlock_sock(sk); 484 atomic_inc(&sk->sk_drops); 485 goto discard_and_relse; 486 } 487 488 bh_unlock_sock(sk); 489 out: 490 sock_put(sk); 491 return rc; 492 discard_and_relse: 493 kfree_skb(skb); 494 goto out; 495 } 496 EXPORT_SYMBOL(__sk_receive_skb); 497 498 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 499 { 500 struct dst_entry *dst = __sk_dst_get(sk); 501 502 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 503 sk_tx_queue_clear(sk); 504 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 505 dst_release(dst); 506 return NULL; 507 } 508 509 return dst; 510 } 511 EXPORT_SYMBOL(__sk_dst_check); 512 513 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 514 { 515 struct dst_entry *dst = sk_dst_get(sk); 516 517 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 518 sk_dst_reset(sk); 519 dst_release(dst); 520 return NULL; 521 } 522 523 return dst; 524 } 525 EXPORT_SYMBOL(sk_dst_check); 526 527 static int sock_setbindtodevice(struct sock *sk, char __user *optval, 528 int optlen) 529 { 530 int ret = -ENOPROTOOPT; 531 #ifdef CONFIG_NETDEVICES 532 struct net *net = sock_net(sk); 533 char devname[IFNAMSIZ]; 534 int index; 535 536 /* Sorry... */ 537 ret = -EPERM; 538 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 539 goto out; 540 541 ret = -EINVAL; 542 if (optlen < 0) 543 goto out; 544 545 /* Bind this socket to a particular device like "eth0", 546 * as specified in the passed interface name. If the 547 * name is "" or the option length is zero the socket 548 * is not bound. 549 */ 550 if (optlen > IFNAMSIZ - 1) 551 optlen = IFNAMSIZ - 1; 552 memset(devname, 0, sizeof(devname)); 553 554 ret = -EFAULT; 555 if (copy_from_user(devname, optval, optlen)) 556 goto out; 557 558 index = 0; 559 if (devname[0] != '\0') { 560 struct net_device *dev; 561 562 rcu_read_lock(); 563 dev = dev_get_by_name_rcu(net, devname); 564 if (dev) 565 index = dev->ifindex; 566 rcu_read_unlock(); 567 ret = -ENODEV; 568 if (!dev) 569 goto out; 570 } 571 572 lock_sock(sk); 573 sk->sk_bound_dev_if = index; 574 sk_dst_reset(sk); 575 release_sock(sk); 576 577 ret = 0; 578 579 out: 580 #endif 581 582 return ret; 583 } 584 585 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 586 int __user *optlen, int len) 587 { 588 int ret = -ENOPROTOOPT; 589 #ifdef CONFIG_NETDEVICES 590 struct net *net = sock_net(sk); 591 char devname[IFNAMSIZ]; 592 593 if (sk->sk_bound_dev_if == 0) { 594 len = 0; 595 goto zero; 596 } 597 598 ret = -EINVAL; 599 if (len < IFNAMSIZ) 600 goto out; 601 602 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); 603 if (ret) 604 goto out; 605 606 len = strlen(devname) + 1; 607 608 ret = -EFAULT; 609 if (copy_to_user(optval, devname, len)) 610 goto out; 611 612 zero: 613 ret = -EFAULT; 614 if (put_user(len, optlen)) 615 goto out; 616 617 ret = 0; 618 619 out: 620 #endif 621 622 return ret; 623 } 624 625 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) 626 { 627 if (valbool) 628 sock_set_flag(sk, bit); 629 else 630 sock_reset_flag(sk, bit); 631 } 632 633 bool sk_mc_loop(struct sock *sk) 634 { 635 if (dev_recursion_level()) 636 return false; 637 if (!sk) 638 return true; 639 switch (sk->sk_family) { 640 case AF_INET: 641 return inet_sk(sk)->mc_loop; 642 #if IS_ENABLED(CONFIG_IPV6) 643 case AF_INET6: 644 return inet6_sk(sk)->mc_loop; 645 #endif 646 } 647 WARN_ON(1); 648 return true; 649 } 650 EXPORT_SYMBOL(sk_mc_loop); 651 652 /* 653 * This is meant for all protocols to use and covers goings on 654 * at the socket level. Everything here is generic. 655 */ 656 657 int sock_setsockopt(struct socket *sock, int level, int optname, 658 char __user *optval, unsigned int optlen) 659 { 660 struct sock *sk = sock->sk; 661 int val; 662 int valbool; 663 struct linger ling; 664 int ret = 0; 665 666 /* 667 * Options without arguments 668 */ 669 670 if (optname == SO_BINDTODEVICE) 671 return sock_setbindtodevice(sk, optval, optlen); 672 673 if (optlen < sizeof(int)) 674 return -EINVAL; 675 676 if (get_user(val, (int __user *)optval)) 677 return -EFAULT; 678 679 valbool = val ? 1 : 0; 680 681 lock_sock(sk); 682 683 switch (optname) { 684 case SO_DEBUG: 685 if (val && !capable(CAP_NET_ADMIN)) 686 ret = -EACCES; 687 else 688 sock_valbool_flag(sk, SOCK_DBG, valbool); 689 break; 690 case SO_REUSEADDR: 691 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 692 break; 693 case SO_REUSEPORT: 694 sk->sk_reuseport = valbool; 695 break; 696 case SO_TYPE: 697 case SO_PROTOCOL: 698 case SO_DOMAIN: 699 case SO_ERROR: 700 ret = -ENOPROTOOPT; 701 break; 702 case SO_DONTROUTE: 703 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 704 break; 705 case SO_BROADCAST: 706 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 707 break; 708 case SO_SNDBUF: 709 /* Don't error on this BSD doesn't and if you think 710 * about it this is right. Otherwise apps have to 711 * play 'guess the biggest size' games. RCVBUF/SNDBUF 712 * are treated in BSD as hints 713 */ 714 val = min_t(u32, val, sysctl_wmem_max); 715 set_sndbuf: 716 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 717 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF); 718 /* Wake up sending tasks if we upped the value. */ 719 sk->sk_write_space(sk); 720 break; 721 722 case SO_SNDBUFFORCE: 723 if (!capable(CAP_NET_ADMIN)) { 724 ret = -EPERM; 725 break; 726 } 727 goto set_sndbuf; 728 729 case SO_RCVBUF: 730 /* Don't error on this BSD doesn't and if you think 731 * about it this is right. Otherwise apps have to 732 * play 'guess the biggest size' games. RCVBUF/SNDBUF 733 * are treated in BSD as hints 734 */ 735 val = min_t(u32, val, sysctl_rmem_max); 736 set_rcvbuf: 737 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 738 /* 739 * We double it on the way in to account for 740 * "struct sk_buff" etc. overhead. Applications 741 * assume that the SO_RCVBUF setting they make will 742 * allow that much actual data to be received on that 743 * socket. 744 * 745 * Applications are unaware that "struct sk_buff" and 746 * other overheads allocate from the receive buffer 747 * during socket buffer allocation. 748 * 749 * And after considering the possible alternatives, 750 * returning the value we actually used in getsockopt 751 * is the most desirable behavior. 752 */ 753 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF); 754 break; 755 756 case SO_RCVBUFFORCE: 757 if (!capable(CAP_NET_ADMIN)) { 758 ret = -EPERM; 759 break; 760 } 761 goto set_rcvbuf; 762 763 case SO_KEEPALIVE: 764 #ifdef CONFIG_INET 765 if (sk->sk_protocol == IPPROTO_TCP && 766 sk->sk_type == SOCK_STREAM) 767 tcp_set_keepalive(sk, valbool); 768 #endif 769 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 770 break; 771 772 case SO_OOBINLINE: 773 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 774 break; 775 776 case SO_NO_CHECK: 777 sk->sk_no_check_tx = valbool; 778 break; 779 780 case SO_PRIORITY: 781 if ((val >= 0 && val <= 6) || 782 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 783 sk->sk_priority = val; 784 else 785 ret = -EPERM; 786 break; 787 788 case SO_LINGER: 789 if (optlen < sizeof(ling)) { 790 ret = -EINVAL; /* 1003.1g */ 791 break; 792 } 793 if (copy_from_user(&ling, optval, sizeof(ling))) { 794 ret = -EFAULT; 795 break; 796 } 797 if (!ling.l_onoff) 798 sock_reset_flag(sk, SOCK_LINGER); 799 else { 800 #if (BITS_PER_LONG == 32) 801 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 802 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 803 else 804 #endif 805 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 806 sock_set_flag(sk, SOCK_LINGER); 807 } 808 break; 809 810 case SO_BSDCOMPAT: 811 sock_warn_obsolete_bsdism("setsockopt"); 812 break; 813 814 case SO_PASSCRED: 815 if (valbool) 816 set_bit(SOCK_PASSCRED, &sock->flags); 817 else 818 clear_bit(SOCK_PASSCRED, &sock->flags); 819 break; 820 821 case SO_TIMESTAMP: 822 case SO_TIMESTAMPNS: 823 if (valbool) { 824 if (optname == SO_TIMESTAMP) 825 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 826 else 827 sock_set_flag(sk, SOCK_RCVTSTAMPNS); 828 sock_set_flag(sk, SOCK_RCVTSTAMP); 829 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 830 } else { 831 sock_reset_flag(sk, SOCK_RCVTSTAMP); 832 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 833 } 834 break; 835 836 case SO_TIMESTAMPING: 837 if (val & ~SOF_TIMESTAMPING_MASK) { 838 ret = -EINVAL; 839 break; 840 } 841 842 if (val & SOF_TIMESTAMPING_OPT_ID && 843 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { 844 if (sk->sk_protocol == IPPROTO_TCP && 845 sk->sk_type == SOCK_STREAM) { 846 if ((1 << sk->sk_state) & 847 (TCPF_CLOSE | TCPF_LISTEN)) { 848 ret = -EINVAL; 849 break; 850 } 851 sk->sk_tskey = tcp_sk(sk)->snd_una; 852 } else { 853 sk->sk_tskey = 0; 854 } 855 } 856 sk->sk_tsflags = val; 857 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 858 sock_enable_timestamp(sk, 859 SOCK_TIMESTAMPING_RX_SOFTWARE); 860 else 861 sock_disable_timestamp(sk, 862 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 863 break; 864 865 case SO_RCVLOWAT: 866 if (val < 0) 867 val = INT_MAX; 868 sk->sk_rcvlowat = val ? : 1; 869 break; 870 871 case SO_RCVTIMEO: 872 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); 873 break; 874 875 case SO_SNDTIMEO: 876 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); 877 break; 878 879 case SO_ATTACH_FILTER: 880 ret = -EINVAL; 881 if (optlen == sizeof(struct sock_fprog)) { 882 struct sock_fprog fprog; 883 884 ret = -EFAULT; 885 if (copy_from_user(&fprog, optval, sizeof(fprog))) 886 break; 887 888 ret = sk_attach_filter(&fprog, sk); 889 } 890 break; 891 892 case SO_ATTACH_BPF: 893 ret = -EINVAL; 894 if (optlen == sizeof(u32)) { 895 u32 ufd; 896 897 ret = -EFAULT; 898 if (copy_from_user(&ufd, optval, sizeof(ufd))) 899 break; 900 901 ret = sk_attach_bpf(ufd, sk); 902 } 903 break; 904 905 case SO_ATTACH_REUSEPORT_CBPF: 906 ret = -EINVAL; 907 if (optlen == sizeof(struct sock_fprog)) { 908 struct sock_fprog fprog; 909 910 ret = -EFAULT; 911 if (copy_from_user(&fprog, optval, sizeof(fprog))) 912 break; 913 914 ret = sk_reuseport_attach_filter(&fprog, sk); 915 } 916 break; 917 918 case SO_ATTACH_REUSEPORT_EBPF: 919 ret = -EINVAL; 920 if (optlen == sizeof(u32)) { 921 u32 ufd; 922 923 ret = -EFAULT; 924 if (copy_from_user(&ufd, optval, sizeof(ufd))) 925 break; 926 927 ret = sk_reuseport_attach_bpf(ufd, sk); 928 } 929 break; 930 931 case SO_DETACH_FILTER: 932 ret = sk_detach_filter(sk); 933 break; 934 935 case SO_LOCK_FILTER: 936 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 937 ret = -EPERM; 938 else 939 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 940 break; 941 942 case SO_PASSSEC: 943 if (valbool) 944 set_bit(SOCK_PASSSEC, &sock->flags); 945 else 946 clear_bit(SOCK_PASSSEC, &sock->flags); 947 break; 948 case SO_MARK: 949 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 950 ret = -EPERM; 951 else 952 sk->sk_mark = val; 953 break; 954 955 case SO_RXQ_OVFL: 956 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 957 break; 958 959 case SO_WIFI_STATUS: 960 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 961 break; 962 963 case SO_PEEK_OFF: 964 if (sock->ops->set_peek_off) 965 ret = sock->ops->set_peek_off(sk, val); 966 else 967 ret = -EOPNOTSUPP; 968 break; 969 970 case SO_NOFCS: 971 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 972 break; 973 974 case SO_SELECT_ERR_QUEUE: 975 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 976 break; 977 978 #ifdef CONFIG_NET_RX_BUSY_POLL 979 case SO_BUSY_POLL: 980 /* allow unprivileged users to decrease the value */ 981 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN)) 982 ret = -EPERM; 983 else { 984 if (val < 0) 985 ret = -EINVAL; 986 else 987 sk->sk_ll_usec = val; 988 } 989 break; 990 #endif 991 992 case SO_MAX_PACING_RATE: 993 sk->sk_max_pacing_rate = val; 994 sk->sk_pacing_rate = min(sk->sk_pacing_rate, 995 sk->sk_max_pacing_rate); 996 break; 997 998 case SO_INCOMING_CPU: 999 sk->sk_incoming_cpu = val; 1000 break; 1001 1002 case SO_CNX_ADVICE: 1003 if (val == 1) 1004 dst_negative_advice(sk); 1005 break; 1006 default: 1007 ret = -ENOPROTOOPT; 1008 break; 1009 } 1010 release_sock(sk); 1011 return ret; 1012 } 1013 EXPORT_SYMBOL(sock_setsockopt); 1014 1015 1016 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 1017 struct ucred *ucred) 1018 { 1019 ucred->pid = pid_vnr(pid); 1020 ucred->uid = ucred->gid = -1; 1021 if (cred) { 1022 struct user_namespace *current_ns = current_user_ns(); 1023 1024 ucred->uid = from_kuid_munged(current_ns, cred->euid); 1025 ucred->gid = from_kgid_munged(current_ns, cred->egid); 1026 } 1027 } 1028 1029 int sock_getsockopt(struct socket *sock, int level, int optname, 1030 char __user *optval, int __user *optlen) 1031 { 1032 struct sock *sk = sock->sk; 1033 1034 union { 1035 int val; 1036 struct linger ling; 1037 struct timeval tm; 1038 } v; 1039 1040 int lv = sizeof(int); 1041 int len; 1042 1043 if (get_user(len, optlen)) 1044 return -EFAULT; 1045 if (len < 0) 1046 return -EINVAL; 1047 1048 memset(&v, 0, sizeof(v)); 1049 1050 switch (optname) { 1051 case SO_DEBUG: 1052 v.val = sock_flag(sk, SOCK_DBG); 1053 break; 1054 1055 case SO_DONTROUTE: 1056 v.val = sock_flag(sk, SOCK_LOCALROUTE); 1057 break; 1058 1059 case SO_BROADCAST: 1060 v.val = sock_flag(sk, SOCK_BROADCAST); 1061 break; 1062 1063 case SO_SNDBUF: 1064 v.val = sk->sk_sndbuf; 1065 break; 1066 1067 case SO_RCVBUF: 1068 v.val = sk->sk_rcvbuf; 1069 break; 1070 1071 case SO_REUSEADDR: 1072 v.val = sk->sk_reuse; 1073 break; 1074 1075 case SO_REUSEPORT: 1076 v.val = sk->sk_reuseport; 1077 break; 1078 1079 case SO_KEEPALIVE: 1080 v.val = sock_flag(sk, SOCK_KEEPOPEN); 1081 break; 1082 1083 case SO_TYPE: 1084 v.val = sk->sk_type; 1085 break; 1086 1087 case SO_PROTOCOL: 1088 v.val = sk->sk_protocol; 1089 break; 1090 1091 case SO_DOMAIN: 1092 v.val = sk->sk_family; 1093 break; 1094 1095 case SO_ERROR: 1096 v.val = -sock_error(sk); 1097 if (v.val == 0) 1098 v.val = xchg(&sk->sk_err_soft, 0); 1099 break; 1100 1101 case SO_OOBINLINE: 1102 v.val = sock_flag(sk, SOCK_URGINLINE); 1103 break; 1104 1105 case SO_NO_CHECK: 1106 v.val = sk->sk_no_check_tx; 1107 break; 1108 1109 case SO_PRIORITY: 1110 v.val = sk->sk_priority; 1111 break; 1112 1113 case SO_LINGER: 1114 lv = sizeof(v.ling); 1115 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1116 v.ling.l_linger = sk->sk_lingertime / HZ; 1117 break; 1118 1119 case SO_BSDCOMPAT: 1120 sock_warn_obsolete_bsdism("getsockopt"); 1121 break; 1122 1123 case SO_TIMESTAMP: 1124 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1125 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1126 break; 1127 1128 case SO_TIMESTAMPNS: 1129 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 1130 break; 1131 1132 case SO_TIMESTAMPING: 1133 v.val = sk->sk_tsflags; 1134 break; 1135 1136 case SO_RCVTIMEO: 1137 lv = sizeof(struct timeval); 1138 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 1139 v.tm.tv_sec = 0; 1140 v.tm.tv_usec = 0; 1141 } else { 1142 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 1143 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 1144 } 1145 break; 1146 1147 case SO_SNDTIMEO: 1148 lv = sizeof(struct timeval); 1149 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 1150 v.tm.tv_sec = 0; 1151 v.tm.tv_usec = 0; 1152 } else { 1153 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1154 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1155 } 1156 break; 1157 1158 case SO_RCVLOWAT: 1159 v.val = sk->sk_rcvlowat; 1160 break; 1161 1162 case SO_SNDLOWAT: 1163 v.val = 1; 1164 break; 1165 1166 case SO_PASSCRED: 1167 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1168 break; 1169 1170 case SO_PEERCRED: 1171 { 1172 struct ucred peercred; 1173 if (len > sizeof(peercred)) 1174 len = sizeof(peercred); 1175 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1176 if (copy_to_user(optval, &peercred, len)) 1177 return -EFAULT; 1178 goto lenout; 1179 } 1180 1181 case SO_PEERNAME: 1182 { 1183 char address[128]; 1184 1185 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1186 return -ENOTCONN; 1187 if (lv < len) 1188 return -EINVAL; 1189 if (copy_to_user(optval, address, len)) 1190 return -EFAULT; 1191 goto lenout; 1192 } 1193 1194 /* Dubious BSD thing... Probably nobody even uses it, but 1195 * the UNIX standard wants it for whatever reason... -DaveM 1196 */ 1197 case SO_ACCEPTCONN: 1198 v.val = sk->sk_state == TCP_LISTEN; 1199 break; 1200 1201 case SO_PASSSEC: 1202 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1203 break; 1204 1205 case SO_PEERSEC: 1206 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1207 1208 case SO_MARK: 1209 v.val = sk->sk_mark; 1210 break; 1211 1212 case SO_RXQ_OVFL: 1213 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1214 break; 1215 1216 case SO_WIFI_STATUS: 1217 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1218 break; 1219 1220 case SO_PEEK_OFF: 1221 if (!sock->ops->set_peek_off) 1222 return -EOPNOTSUPP; 1223 1224 v.val = sk->sk_peek_off; 1225 break; 1226 case SO_NOFCS: 1227 v.val = sock_flag(sk, SOCK_NOFCS); 1228 break; 1229 1230 case SO_BINDTODEVICE: 1231 return sock_getbindtodevice(sk, optval, optlen, len); 1232 1233 case SO_GET_FILTER: 1234 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1235 if (len < 0) 1236 return len; 1237 1238 goto lenout; 1239 1240 case SO_LOCK_FILTER: 1241 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1242 break; 1243 1244 case SO_BPF_EXTENSIONS: 1245 v.val = bpf_tell_extensions(); 1246 break; 1247 1248 case SO_SELECT_ERR_QUEUE: 1249 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1250 break; 1251 1252 #ifdef CONFIG_NET_RX_BUSY_POLL 1253 case SO_BUSY_POLL: 1254 v.val = sk->sk_ll_usec; 1255 break; 1256 #endif 1257 1258 case SO_MAX_PACING_RATE: 1259 v.val = sk->sk_max_pacing_rate; 1260 break; 1261 1262 case SO_INCOMING_CPU: 1263 v.val = sk->sk_incoming_cpu; 1264 break; 1265 1266 default: 1267 /* We implement the SO_SNDLOWAT etc to not be settable 1268 * (1003.1g 7). 1269 */ 1270 return -ENOPROTOOPT; 1271 } 1272 1273 if (len > lv) 1274 len = lv; 1275 if (copy_to_user(optval, &v, len)) 1276 return -EFAULT; 1277 lenout: 1278 if (put_user(len, optlen)) 1279 return -EFAULT; 1280 return 0; 1281 } 1282 1283 /* 1284 * Initialize an sk_lock. 1285 * 1286 * (We also register the sk_lock with the lock validator.) 1287 */ 1288 static inline void sock_lock_init(struct sock *sk) 1289 { 1290 sock_lock_init_class_and_name(sk, 1291 af_family_slock_key_strings[sk->sk_family], 1292 af_family_slock_keys + sk->sk_family, 1293 af_family_key_strings[sk->sk_family], 1294 af_family_keys + sk->sk_family); 1295 } 1296 1297 /* 1298 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1299 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1300 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1301 */ 1302 static void sock_copy(struct sock *nsk, const struct sock *osk) 1303 { 1304 #ifdef CONFIG_SECURITY_NETWORK 1305 void *sptr = nsk->sk_security; 1306 #endif 1307 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1308 1309 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1310 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1311 1312 #ifdef CONFIG_SECURITY_NETWORK 1313 nsk->sk_security = sptr; 1314 security_sk_clone(osk, nsk); 1315 #endif 1316 } 1317 1318 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1319 int family) 1320 { 1321 struct sock *sk; 1322 struct kmem_cache *slab; 1323 1324 slab = prot->slab; 1325 if (slab != NULL) { 1326 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1327 if (!sk) 1328 return sk; 1329 if (priority & __GFP_ZERO) 1330 sk_prot_clear_nulls(sk, prot->obj_size); 1331 } else 1332 sk = kmalloc(prot->obj_size, priority); 1333 1334 if (sk != NULL) { 1335 kmemcheck_annotate_bitfield(sk, flags); 1336 1337 if (security_sk_alloc(sk, family, priority)) 1338 goto out_free; 1339 1340 if (!try_module_get(prot->owner)) 1341 goto out_free_sec; 1342 sk_tx_queue_clear(sk); 1343 cgroup_sk_alloc(&sk->sk_cgrp_data); 1344 } 1345 1346 return sk; 1347 1348 out_free_sec: 1349 security_sk_free(sk); 1350 out_free: 1351 if (slab != NULL) 1352 kmem_cache_free(slab, sk); 1353 else 1354 kfree(sk); 1355 return NULL; 1356 } 1357 1358 static void sk_prot_free(struct proto *prot, struct sock *sk) 1359 { 1360 struct kmem_cache *slab; 1361 struct module *owner; 1362 1363 owner = prot->owner; 1364 slab = prot->slab; 1365 1366 cgroup_sk_free(&sk->sk_cgrp_data); 1367 security_sk_free(sk); 1368 if (slab != NULL) 1369 kmem_cache_free(slab, sk); 1370 else 1371 kfree(sk); 1372 module_put(owner); 1373 } 1374 1375 /** 1376 * sk_alloc - All socket objects are allocated here 1377 * @net: the applicable net namespace 1378 * @family: protocol family 1379 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1380 * @prot: struct proto associated with this new sock instance 1381 * @kern: is this to be a kernel socket? 1382 */ 1383 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1384 struct proto *prot, int kern) 1385 { 1386 struct sock *sk; 1387 1388 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1389 if (sk) { 1390 sk->sk_family = family; 1391 /* 1392 * See comment in struct sock definition to understand 1393 * why we need sk_prot_creator -acme 1394 */ 1395 sk->sk_prot = sk->sk_prot_creator = prot; 1396 sock_lock_init(sk); 1397 sk->sk_net_refcnt = kern ? 0 : 1; 1398 if (likely(sk->sk_net_refcnt)) 1399 get_net(net); 1400 sock_net_set(sk, net); 1401 atomic_set(&sk->sk_wmem_alloc, 1); 1402 1403 sock_update_classid(&sk->sk_cgrp_data); 1404 sock_update_netprioidx(&sk->sk_cgrp_data); 1405 } 1406 1407 return sk; 1408 } 1409 EXPORT_SYMBOL(sk_alloc); 1410 1411 /* Sockets having SOCK_RCU_FREE will call this function after one RCU 1412 * grace period. This is the case for UDP sockets and TCP listeners. 1413 */ 1414 static void __sk_destruct(struct rcu_head *head) 1415 { 1416 struct sock *sk = container_of(head, struct sock, sk_rcu); 1417 struct sk_filter *filter; 1418 1419 if (sk->sk_destruct) 1420 sk->sk_destruct(sk); 1421 1422 filter = rcu_dereference_check(sk->sk_filter, 1423 atomic_read(&sk->sk_wmem_alloc) == 0); 1424 if (filter) { 1425 sk_filter_uncharge(sk, filter); 1426 RCU_INIT_POINTER(sk->sk_filter, NULL); 1427 } 1428 if (rcu_access_pointer(sk->sk_reuseport_cb)) 1429 reuseport_detach_sock(sk); 1430 1431 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1432 1433 if (atomic_read(&sk->sk_omem_alloc)) 1434 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1435 __func__, atomic_read(&sk->sk_omem_alloc)); 1436 1437 if (sk->sk_peer_cred) 1438 put_cred(sk->sk_peer_cred); 1439 put_pid(sk->sk_peer_pid); 1440 if (likely(sk->sk_net_refcnt)) 1441 put_net(sock_net(sk)); 1442 sk_prot_free(sk->sk_prot_creator, sk); 1443 } 1444 1445 void sk_destruct(struct sock *sk) 1446 { 1447 if (sock_flag(sk, SOCK_RCU_FREE)) 1448 call_rcu(&sk->sk_rcu, __sk_destruct); 1449 else 1450 __sk_destruct(&sk->sk_rcu); 1451 } 1452 1453 static void __sk_free(struct sock *sk) 1454 { 1455 if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt)) 1456 sock_diag_broadcast_destroy(sk); 1457 else 1458 sk_destruct(sk); 1459 } 1460 1461 void sk_free(struct sock *sk) 1462 { 1463 /* 1464 * We subtract one from sk_wmem_alloc and can know if 1465 * some packets are still in some tx queue. 1466 * If not null, sock_wfree() will call __sk_free(sk) later 1467 */ 1468 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1469 __sk_free(sk); 1470 } 1471 EXPORT_SYMBOL(sk_free); 1472 1473 /** 1474 * sk_clone_lock - clone a socket, and lock its clone 1475 * @sk: the socket to clone 1476 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1477 * 1478 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1479 */ 1480 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1481 { 1482 struct sock *newsk; 1483 bool is_charged = true; 1484 1485 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1486 if (newsk != NULL) { 1487 struct sk_filter *filter; 1488 1489 sock_copy(newsk, sk); 1490 1491 /* SANITY */ 1492 if (likely(newsk->sk_net_refcnt)) 1493 get_net(sock_net(newsk)); 1494 sk_node_init(&newsk->sk_node); 1495 sock_lock_init(newsk); 1496 bh_lock_sock(newsk); 1497 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1498 newsk->sk_backlog.len = 0; 1499 1500 atomic_set(&newsk->sk_rmem_alloc, 0); 1501 /* 1502 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1503 */ 1504 atomic_set(&newsk->sk_wmem_alloc, 1); 1505 atomic_set(&newsk->sk_omem_alloc, 0); 1506 skb_queue_head_init(&newsk->sk_receive_queue); 1507 skb_queue_head_init(&newsk->sk_write_queue); 1508 1509 rwlock_init(&newsk->sk_callback_lock); 1510 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1511 af_callback_keys + newsk->sk_family, 1512 af_family_clock_key_strings[newsk->sk_family]); 1513 1514 newsk->sk_dst_cache = NULL; 1515 newsk->sk_wmem_queued = 0; 1516 newsk->sk_forward_alloc = 0; 1517 atomic_set(&newsk->sk_drops, 0); 1518 newsk->sk_send_head = NULL; 1519 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1520 1521 sock_reset_flag(newsk, SOCK_DONE); 1522 skb_queue_head_init(&newsk->sk_error_queue); 1523 1524 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1525 if (filter != NULL) 1526 /* though it's an empty new sock, the charging may fail 1527 * if sysctl_optmem_max was changed between creation of 1528 * original socket and cloning 1529 */ 1530 is_charged = sk_filter_charge(newsk, filter); 1531 1532 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) { 1533 /* It is still raw copy of parent, so invalidate 1534 * destructor and make plain sk_free() */ 1535 newsk->sk_destruct = NULL; 1536 bh_unlock_sock(newsk); 1537 sk_free(newsk); 1538 newsk = NULL; 1539 goto out; 1540 } 1541 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL); 1542 1543 newsk->sk_err = 0; 1544 newsk->sk_priority = 0; 1545 newsk->sk_incoming_cpu = raw_smp_processor_id(); 1546 atomic64_set(&newsk->sk_cookie, 0); 1547 /* 1548 * Before updating sk_refcnt, we must commit prior changes to memory 1549 * (Documentation/RCU/rculist_nulls.txt for details) 1550 */ 1551 smp_wmb(); 1552 atomic_set(&newsk->sk_refcnt, 2); 1553 1554 /* 1555 * Increment the counter in the same struct proto as the master 1556 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1557 * is the same as sk->sk_prot->socks, as this field was copied 1558 * with memcpy). 1559 * 1560 * This _changes_ the previous behaviour, where 1561 * tcp_create_openreq_child always was incrementing the 1562 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1563 * to be taken into account in all callers. -acme 1564 */ 1565 sk_refcnt_debug_inc(newsk); 1566 sk_set_socket(newsk, NULL); 1567 newsk->sk_wq = NULL; 1568 1569 if (mem_cgroup_sockets_enabled && sk->sk_memcg) 1570 sock_update_memcg(newsk); 1571 1572 if (newsk->sk_prot->sockets_allocated) 1573 sk_sockets_allocated_inc(newsk); 1574 1575 if (sock_needs_netstamp(sk) && 1576 newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1577 net_enable_timestamp(); 1578 } 1579 out: 1580 return newsk; 1581 } 1582 EXPORT_SYMBOL_GPL(sk_clone_lock); 1583 1584 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1585 { 1586 u32 max_segs = 1; 1587 1588 sk_dst_set(sk, dst); 1589 sk->sk_route_caps = dst->dev->features; 1590 if (sk->sk_route_caps & NETIF_F_GSO) 1591 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1592 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1593 if (sk_can_gso(sk)) { 1594 if (dst->header_len) { 1595 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1596 } else { 1597 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1598 sk->sk_gso_max_size = dst->dev->gso_max_size; 1599 max_segs = max_t(u32, dst->dev->gso_max_segs, 1); 1600 } 1601 } 1602 sk->sk_gso_max_segs = max_segs; 1603 } 1604 EXPORT_SYMBOL_GPL(sk_setup_caps); 1605 1606 /* 1607 * Simple resource managers for sockets. 1608 */ 1609 1610 1611 /* 1612 * Write buffer destructor automatically called from kfree_skb. 1613 */ 1614 void sock_wfree(struct sk_buff *skb) 1615 { 1616 struct sock *sk = skb->sk; 1617 unsigned int len = skb->truesize; 1618 1619 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1620 /* 1621 * Keep a reference on sk_wmem_alloc, this will be released 1622 * after sk_write_space() call 1623 */ 1624 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1625 sk->sk_write_space(sk); 1626 len = 1; 1627 } 1628 /* 1629 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1630 * could not do because of in-flight packets 1631 */ 1632 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1633 __sk_free(sk); 1634 } 1635 EXPORT_SYMBOL(sock_wfree); 1636 1637 /* This variant of sock_wfree() is used by TCP, 1638 * since it sets SOCK_USE_WRITE_QUEUE. 1639 */ 1640 void __sock_wfree(struct sk_buff *skb) 1641 { 1642 struct sock *sk = skb->sk; 1643 1644 if (atomic_sub_and_test(skb->truesize, &sk->sk_wmem_alloc)) 1645 __sk_free(sk); 1646 } 1647 1648 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) 1649 { 1650 skb_orphan(skb); 1651 skb->sk = sk; 1652 #ifdef CONFIG_INET 1653 if (unlikely(!sk_fullsock(sk))) { 1654 skb->destructor = sock_edemux; 1655 sock_hold(sk); 1656 return; 1657 } 1658 #endif 1659 skb->destructor = sock_wfree; 1660 skb_set_hash_from_sk(skb, sk); 1661 /* 1662 * We used to take a refcount on sk, but following operation 1663 * is enough to guarantee sk_free() wont free this sock until 1664 * all in-flight packets are completed 1665 */ 1666 atomic_add(skb->truesize, &sk->sk_wmem_alloc); 1667 } 1668 EXPORT_SYMBOL(skb_set_owner_w); 1669 1670 /* This helper is used by netem, as it can hold packets in its 1671 * delay queue. We want to allow the owner socket to send more 1672 * packets, as if they were already TX completed by a typical driver. 1673 * But we also want to keep skb->sk set because some packet schedulers 1674 * rely on it (sch_fq for example). So we set skb->truesize to a small 1675 * amount (1) and decrease sk_wmem_alloc accordingly. 1676 */ 1677 void skb_orphan_partial(struct sk_buff *skb) 1678 { 1679 /* If this skb is a TCP pure ACK or already went here, 1680 * we have nothing to do. 2 is already a very small truesize. 1681 */ 1682 if (skb->truesize <= 2) 1683 return; 1684 1685 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc, 1686 * so we do not completely orphan skb, but transfert all 1687 * accounted bytes but one, to avoid unexpected reorders. 1688 */ 1689 if (skb->destructor == sock_wfree 1690 #ifdef CONFIG_INET 1691 || skb->destructor == tcp_wfree 1692 #endif 1693 ) { 1694 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc); 1695 skb->truesize = 1; 1696 } else { 1697 skb_orphan(skb); 1698 } 1699 } 1700 EXPORT_SYMBOL(skb_orphan_partial); 1701 1702 /* 1703 * Read buffer destructor automatically called from kfree_skb. 1704 */ 1705 void sock_rfree(struct sk_buff *skb) 1706 { 1707 struct sock *sk = skb->sk; 1708 unsigned int len = skb->truesize; 1709 1710 atomic_sub(len, &sk->sk_rmem_alloc); 1711 sk_mem_uncharge(sk, len); 1712 } 1713 EXPORT_SYMBOL(sock_rfree); 1714 1715 /* 1716 * Buffer destructor for skbs that are not used directly in read or write 1717 * path, e.g. for error handler skbs. Automatically called from kfree_skb. 1718 */ 1719 void sock_efree(struct sk_buff *skb) 1720 { 1721 sock_put(skb->sk); 1722 } 1723 EXPORT_SYMBOL(sock_efree); 1724 1725 kuid_t sock_i_uid(struct sock *sk) 1726 { 1727 kuid_t uid; 1728 1729 read_lock_bh(&sk->sk_callback_lock); 1730 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1731 read_unlock_bh(&sk->sk_callback_lock); 1732 return uid; 1733 } 1734 EXPORT_SYMBOL(sock_i_uid); 1735 1736 unsigned long sock_i_ino(struct sock *sk) 1737 { 1738 unsigned long ino; 1739 1740 read_lock_bh(&sk->sk_callback_lock); 1741 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1742 read_unlock_bh(&sk->sk_callback_lock); 1743 return ino; 1744 } 1745 EXPORT_SYMBOL(sock_i_ino); 1746 1747 /* 1748 * Allocate a skb from the socket's send buffer. 1749 */ 1750 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1751 gfp_t priority) 1752 { 1753 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1754 struct sk_buff *skb = alloc_skb(size, priority); 1755 if (skb) { 1756 skb_set_owner_w(skb, sk); 1757 return skb; 1758 } 1759 } 1760 return NULL; 1761 } 1762 EXPORT_SYMBOL(sock_wmalloc); 1763 1764 /* 1765 * Allocate a memory block from the socket's option memory buffer. 1766 */ 1767 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1768 { 1769 if ((unsigned int)size <= sysctl_optmem_max && 1770 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1771 void *mem; 1772 /* First do the add, to avoid the race if kmalloc 1773 * might sleep. 1774 */ 1775 atomic_add(size, &sk->sk_omem_alloc); 1776 mem = kmalloc(size, priority); 1777 if (mem) 1778 return mem; 1779 atomic_sub(size, &sk->sk_omem_alloc); 1780 } 1781 return NULL; 1782 } 1783 EXPORT_SYMBOL(sock_kmalloc); 1784 1785 /* Free an option memory block. Note, we actually want the inline 1786 * here as this allows gcc to detect the nullify and fold away the 1787 * condition entirely. 1788 */ 1789 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size, 1790 const bool nullify) 1791 { 1792 if (WARN_ON_ONCE(!mem)) 1793 return; 1794 if (nullify) 1795 kzfree(mem); 1796 else 1797 kfree(mem); 1798 atomic_sub(size, &sk->sk_omem_alloc); 1799 } 1800 1801 void sock_kfree_s(struct sock *sk, void *mem, int size) 1802 { 1803 __sock_kfree_s(sk, mem, size, false); 1804 } 1805 EXPORT_SYMBOL(sock_kfree_s); 1806 1807 void sock_kzfree_s(struct sock *sk, void *mem, int size) 1808 { 1809 __sock_kfree_s(sk, mem, size, true); 1810 } 1811 EXPORT_SYMBOL(sock_kzfree_s); 1812 1813 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1814 I think, these locks should be removed for datagram sockets. 1815 */ 1816 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1817 { 1818 DEFINE_WAIT(wait); 1819 1820 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); 1821 for (;;) { 1822 if (!timeo) 1823 break; 1824 if (signal_pending(current)) 1825 break; 1826 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1827 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1828 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1829 break; 1830 if (sk->sk_shutdown & SEND_SHUTDOWN) 1831 break; 1832 if (sk->sk_err) 1833 break; 1834 timeo = schedule_timeout(timeo); 1835 } 1836 finish_wait(sk_sleep(sk), &wait); 1837 return timeo; 1838 } 1839 1840 1841 /* 1842 * Generic send/receive buffer handlers 1843 */ 1844 1845 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1846 unsigned long data_len, int noblock, 1847 int *errcode, int max_page_order) 1848 { 1849 struct sk_buff *skb; 1850 long timeo; 1851 int err; 1852 1853 timeo = sock_sndtimeo(sk, noblock); 1854 for (;;) { 1855 err = sock_error(sk); 1856 if (err != 0) 1857 goto failure; 1858 1859 err = -EPIPE; 1860 if (sk->sk_shutdown & SEND_SHUTDOWN) 1861 goto failure; 1862 1863 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf) 1864 break; 1865 1866 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); 1867 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1868 err = -EAGAIN; 1869 if (!timeo) 1870 goto failure; 1871 if (signal_pending(current)) 1872 goto interrupted; 1873 timeo = sock_wait_for_wmem(sk, timeo); 1874 } 1875 skb = alloc_skb_with_frags(header_len, data_len, max_page_order, 1876 errcode, sk->sk_allocation); 1877 if (skb) 1878 skb_set_owner_w(skb, sk); 1879 return skb; 1880 1881 interrupted: 1882 err = sock_intr_errno(timeo); 1883 failure: 1884 *errcode = err; 1885 return NULL; 1886 } 1887 EXPORT_SYMBOL(sock_alloc_send_pskb); 1888 1889 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1890 int noblock, int *errcode) 1891 { 1892 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1893 } 1894 EXPORT_SYMBOL(sock_alloc_send_skb); 1895 1896 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, 1897 struct sockcm_cookie *sockc) 1898 { 1899 u32 tsflags; 1900 1901 switch (cmsg->cmsg_type) { 1902 case SO_MARK: 1903 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 1904 return -EPERM; 1905 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 1906 return -EINVAL; 1907 sockc->mark = *(u32 *)CMSG_DATA(cmsg); 1908 break; 1909 case SO_TIMESTAMPING: 1910 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 1911 return -EINVAL; 1912 1913 tsflags = *(u32 *)CMSG_DATA(cmsg); 1914 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK) 1915 return -EINVAL; 1916 1917 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK; 1918 sockc->tsflags |= tsflags; 1919 break; 1920 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */ 1921 case SCM_RIGHTS: 1922 case SCM_CREDENTIALS: 1923 break; 1924 default: 1925 return -EINVAL; 1926 } 1927 return 0; 1928 } 1929 EXPORT_SYMBOL(__sock_cmsg_send); 1930 1931 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1932 struct sockcm_cookie *sockc) 1933 { 1934 struct cmsghdr *cmsg; 1935 int ret; 1936 1937 for_each_cmsghdr(cmsg, msg) { 1938 if (!CMSG_OK(msg, cmsg)) 1939 return -EINVAL; 1940 if (cmsg->cmsg_level != SOL_SOCKET) 1941 continue; 1942 ret = __sock_cmsg_send(sk, msg, cmsg, sockc); 1943 if (ret) 1944 return ret; 1945 } 1946 return 0; 1947 } 1948 EXPORT_SYMBOL(sock_cmsg_send); 1949 1950 /* On 32bit arches, an skb frag is limited to 2^15 */ 1951 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1952 1953 /** 1954 * skb_page_frag_refill - check that a page_frag contains enough room 1955 * @sz: minimum size of the fragment we want to get 1956 * @pfrag: pointer to page_frag 1957 * @gfp: priority for memory allocation 1958 * 1959 * Note: While this allocator tries to use high order pages, there is 1960 * no guarantee that allocations succeed. Therefore, @sz MUST be 1961 * less or equal than PAGE_SIZE. 1962 */ 1963 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp) 1964 { 1965 if (pfrag->page) { 1966 if (page_ref_count(pfrag->page) == 1) { 1967 pfrag->offset = 0; 1968 return true; 1969 } 1970 if (pfrag->offset + sz <= pfrag->size) 1971 return true; 1972 put_page(pfrag->page); 1973 } 1974 1975 pfrag->offset = 0; 1976 if (SKB_FRAG_PAGE_ORDER) { 1977 /* Avoid direct reclaim but allow kswapd to wake */ 1978 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) | 1979 __GFP_COMP | __GFP_NOWARN | 1980 __GFP_NORETRY, 1981 SKB_FRAG_PAGE_ORDER); 1982 if (likely(pfrag->page)) { 1983 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER; 1984 return true; 1985 } 1986 } 1987 pfrag->page = alloc_page(gfp); 1988 if (likely(pfrag->page)) { 1989 pfrag->size = PAGE_SIZE; 1990 return true; 1991 } 1992 return false; 1993 } 1994 EXPORT_SYMBOL(skb_page_frag_refill); 1995 1996 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 1997 { 1998 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 1999 return true; 2000 2001 sk_enter_memory_pressure(sk); 2002 sk_stream_moderate_sndbuf(sk); 2003 return false; 2004 } 2005 EXPORT_SYMBOL(sk_page_frag_refill); 2006 2007 static void __lock_sock(struct sock *sk) 2008 __releases(&sk->sk_lock.slock) 2009 __acquires(&sk->sk_lock.slock) 2010 { 2011 DEFINE_WAIT(wait); 2012 2013 for (;;) { 2014 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 2015 TASK_UNINTERRUPTIBLE); 2016 spin_unlock_bh(&sk->sk_lock.slock); 2017 schedule(); 2018 spin_lock_bh(&sk->sk_lock.slock); 2019 if (!sock_owned_by_user(sk)) 2020 break; 2021 } 2022 finish_wait(&sk->sk_lock.wq, &wait); 2023 } 2024 2025 static void __release_sock(struct sock *sk) 2026 __releases(&sk->sk_lock.slock) 2027 __acquires(&sk->sk_lock.slock) 2028 { 2029 struct sk_buff *skb, *next; 2030 2031 while ((skb = sk->sk_backlog.head) != NULL) { 2032 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 2033 2034 spin_unlock_bh(&sk->sk_lock.slock); 2035 2036 do { 2037 next = skb->next; 2038 prefetch(next); 2039 WARN_ON_ONCE(skb_dst_is_noref(skb)); 2040 skb->next = NULL; 2041 sk_backlog_rcv(sk, skb); 2042 2043 cond_resched(); 2044 2045 skb = next; 2046 } while (skb != NULL); 2047 2048 spin_lock_bh(&sk->sk_lock.slock); 2049 } 2050 2051 /* 2052 * Doing the zeroing here guarantee we can not loop forever 2053 * while a wild producer attempts to flood us. 2054 */ 2055 sk->sk_backlog.len = 0; 2056 } 2057 2058 void __sk_flush_backlog(struct sock *sk) 2059 { 2060 spin_lock_bh(&sk->sk_lock.slock); 2061 __release_sock(sk); 2062 spin_unlock_bh(&sk->sk_lock.slock); 2063 } 2064 2065 /** 2066 * sk_wait_data - wait for data to arrive at sk_receive_queue 2067 * @sk: sock to wait on 2068 * @timeo: for how long 2069 * @skb: last skb seen on sk_receive_queue 2070 * 2071 * Now socket state including sk->sk_err is changed only under lock, 2072 * hence we may omit checks after joining wait queue. 2073 * We check receive queue before schedule() only as optimization; 2074 * it is very likely that release_sock() added new data. 2075 */ 2076 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb) 2077 { 2078 int rc; 2079 DEFINE_WAIT(wait); 2080 2081 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 2082 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); 2083 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb); 2084 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); 2085 finish_wait(sk_sleep(sk), &wait); 2086 return rc; 2087 } 2088 EXPORT_SYMBOL(sk_wait_data); 2089 2090 /** 2091 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 2092 * @sk: socket 2093 * @size: memory size to allocate 2094 * @kind: allocation type 2095 * 2096 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 2097 * rmem allocation. This function assumes that protocols which have 2098 * memory_pressure use sk_wmem_queued as write buffer accounting. 2099 */ 2100 int __sk_mem_schedule(struct sock *sk, int size, int kind) 2101 { 2102 struct proto *prot = sk->sk_prot; 2103 int amt = sk_mem_pages(size); 2104 long allocated; 2105 2106 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; 2107 2108 allocated = sk_memory_allocated_add(sk, amt); 2109 2110 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 2111 !mem_cgroup_charge_skmem(sk->sk_memcg, amt)) 2112 goto suppress_allocation; 2113 2114 /* Under limit. */ 2115 if (allocated <= sk_prot_mem_limits(sk, 0)) { 2116 sk_leave_memory_pressure(sk); 2117 return 1; 2118 } 2119 2120 /* Under pressure. */ 2121 if (allocated > sk_prot_mem_limits(sk, 1)) 2122 sk_enter_memory_pressure(sk); 2123 2124 /* Over hard limit. */ 2125 if (allocated > sk_prot_mem_limits(sk, 2)) 2126 goto suppress_allocation; 2127 2128 /* guarantee minimum buffer size under pressure */ 2129 if (kind == SK_MEM_RECV) { 2130 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 2131 return 1; 2132 2133 } else { /* SK_MEM_SEND */ 2134 if (sk->sk_type == SOCK_STREAM) { 2135 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 2136 return 1; 2137 } else if (atomic_read(&sk->sk_wmem_alloc) < 2138 prot->sysctl_wmem[0]) 2139 return 1; 2140 } 2141 2142 if (sk_has_memory_pressure(sk)) { 2143 int alloc; 2144 2145 if (!sk_under_memory_pressure(sk)) 2146 return 1; 2147 alloc = sk_sockets_allocated_read_positive(sk); 2148 if (sk_prot_mem_limits(sk, 2) > alloc * 2149 sk_mem_pages(sk->sk_wmem_queued + 2150 atomic_read(&sk->sk_rmem_alloc) + 2151 sk->sk_forward_alloc)) 2152 return 1; 2153 } 2154 2155 suppress_allocation: 2156 2157 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2158 sk_stream_moderate_sndbuf(sk); 2159 2160 /* Fail only if socket is _under_ its sndbuf. 2161 * In this case we cannot block, so that we have to fail. 2162 */ 2163 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2164 return 1; 2165 } 2166 2167 trace_sock_exceed_buf_limit(sk, prot, allocated); 2168 2169 /* Alas. Undo changes. */ 2170 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM; 2171 2172 sk_memory_allocated_sub(sk, amt); 2173 2174 if (mem_cgroup_sockets_enabled && sk->sk_memcg) 2175 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt); 2176 2177 return 0; 2178 } 2179 EXPORT_SYMBOL(__sk_mem_schedule); 2180 2181 /** 2182 * __sk_mem_reclaim - reclaim memory_allocated 2183 * @sk: socket 2184 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple) 2185 */ 2186 void __sk_mem_reclaim(struct sock *sk, int amount) 2187 { 2188 amount >>= SK_MEM_QUANTUM_SHIFT; 2189 sk_memory_allocated_sub(sk, amount); 2190 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT; 2191 2192 if (mem_cgroup_sockets_enabled && sk->sk_memcg) 2193 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount); 2194 2195 if (sk_under_memory_pressure(sk) && 2196 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2197 sk_leave_memory_pressure(sk); 2198 } 2199 EXPORT_SYMBOL(__sk_mem_reclaim); 2200 2201 int sk_set_peek_off(struct sock *sk, int val) 2202 { 2203 if (val < 0) 2204 return -EINVAL; 2205 2206 sk->sk_peek_off = val; 2207 return 0; 2208 } 2209 EXPORT_SYMBOL_GPL(sk_set_peek_off); 2210 2211 /* 2212 * Set of default routines for initialising struct proto_ops when 2213 * the protocol does not support a particular function. In certain 2214 * cases where it makes no sense for a protocol to have a "do nothing" 2215 * function, some default processing is provided. 2216 */ 2217 2218 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2219 { 2220 return -EOPNOTSUPP; 2221 } 2222 EXPORT_SYMBOL(sock_no_bind); 2223 2224 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2225 int len, int flags) 2226 { 2227 return -EOPNOTSUPP; 2228 } 2229 EXPORT_SYMBOL(sock_no_connect); 2230 2231 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2232 { 2233 return -EOPNOTSUPP; 2234 } 2235 EXPORT_SYMBOL(sock_no_socketpair); 2236 2237 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 2238 { 2239 return -EOPNOTSUPP; 2240 } 2241 EXPORT_SYMBOL(sock_no_accept); 2242 2243 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2244 int *len, int peer) 2245 { 2246 return -EOPNOTSUPP; 2247 } 2248 EXPORT_SYMBOL(sock_no_getname); 2249 2250 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 2251 { 2252 return 0; 2253 } 2254 EXPORT_SYMBOL(sock_no_poll); 2255 2256 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2257 { 2258 return -EOPNOTSUPP; 2259 } 2260 EXPORT_SYMBOL(sock_no_ioctl); 2261 2262 int sock_no_listen(struct socket *sock, int backlog) 2263 { 2264 return -EOPNOTSUPP; 2265 } 2266 EXPORT_SYMBOL(sock_no_listen); 2267 2268 int sock_no_shutdown(struct socket *sock, int how) 2269 { 2270 return -EOPNOTSUPP; 2271 } 2272 EXPORT_SYMBOL(sock_no_shutdown); 2273 2274 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2275 char __user *optval, unsigned int optlen) 2276 { 2277 return -EOPNOTSUPP; 2278 } 2279 EXPORT_SYMBOL(sock_no_setsockopt); 2280 2281 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2282 char __user *optval, int __user *optlen) 2283 { 2284 return -EOPNOTSUPP; 2285 } 2286 EXPORT_SYMBOL(sock_no_getsockopt); 2287 2288 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len) 2289 { 2290 return -EOPNOTSUPP; 2291 } 2292 EXPORT_SYMBOL(sock_no_sendmsg); 2293 2294 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len, 2295 int flags) 2296 { 2297 return -EOPNOTSUPP; 2298 } 2299 EXPORT_SYMBOL(sock_no_recvmsg); 2300 2301 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2302 { 2303 /* Mirror missing mmap method error code */ 2304 return -ENODEV; 2305 } 2306 EXPORT_SYMBOL(sock_no_mmap); 2307 2308 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2309 { 2310 ssize_t res; 2311 struct msghdr msg = {.msg_flags = flags}; 2312 struct kvec iov; 2313 char *kaddr = kmap(page); 2314 iov.iov_base = kaddr + offset; 2315 iov.iov_len = size; 2316 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2317 kunmap(page); 2318 return res; 2319 } 2320 EXPORT_SYMBOL(sock_no_sendpage); 2321 2322 /* 2323 * Default Socket Callbacks 2324 */ 2325 2326 static void sock_def_wakeup(struct sock *sk) 2327 { 2328 struct socket_wq *wq; 2329 2330 rcu_read_lock(); 2331 wq = rcu_dereference(sk->sk_wq); 2332 if (skwq_has_sleeper(wq)) 2333 wake_up_interruptible_all(&wq->wait); 2334 rcu_read_unlock(); 2335 } 2336 2337 static void sock_def_error_report(struct sock *sk) 2338 { 2339 struct socket_wq *wq; 2340 2341 rcu_read_lock(); 2342 wq = rcu_dereference(sk->sk_wq); 2343 if (skwq_has_sleeper(wq)) 2344 wake_up_interruptible_poll(&wq->wait, POLLERR); 2345 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2346 rcu_read_unlock(); 2347 } 2348 2349 static void sock_def_readable(struct sock *sk) 2350 { 2351 struct socket_wq *wq; 2352 2353 rcu_read_lock(); 2354 wq = rcu_dereference(sk->sk_wq); 2355 if (skwq_has_sleeper(wq)) 2356 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI | 2357 POLLRDNORM | POLLRDBAND); 2358 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2359 rcu_read_unlock(); 2360 } 2361 2362 static void sock_def_write_space(struct sock *sk) 2363 { 2364 struct socket_wq *wq; 2365 2366 rcu_read_lock(); 2367 2368 /* Do not wake up a writer until he can make "significant" 2369 * progress. --DaveM 2370 */ 2371 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2372 wq = rcu_dereference(sk->sk_wq); 2373 if (skwq_has_sleeper(wq)) 2374 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 2375 POLLWRNORM | POLLWRBAND); 2376 2377 /* Should agree with poll, otherwise some programs break */ 2378 if (sock_writeable(sk)) 2379 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2380 } 2381 2382 rcu_read_unlock(); 2383 } 2384 2385 static void sock_def_destruct(struct sock *sk) 2386 { 2387 } 2388 2389 void sk_send_sigurg(struct sock *sk) 2390 { 2391 if (sk->sk_socket && sk->sk_socket->file) 2392 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2393 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2394 } 2395 EXPORT_SYMBOL(sk_send_sigurg); 2396 2397 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2398 unsigned long expires) 2399 { 2400 if (!mod_timer(timer, expires)) 2401 sock_hold(sk); 2402 } 2403 EXPORT_SYMBOL(sk_reset_timer); 2404 2405 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2406 { 2407 if (del_timer(timer)) 2408 __sock_put(sk); 2409 } 2410 EXPORT_SYMBOL(sk_stop_timer); 2411 2412 void sock_init_data(struct socket *sock, struct sock *sk) 2413 { 2414 skb_queue_head_init(&sk->sk_receive_queue); 2415 skb_queue_head_init(&sk->sk_write_queue); 2416 skb_queue_head_init(&sk->sk_error_queue); 2417 2418 sk->sk_send_head = NULL; 2419 2420 init_timer(&sk->sk_timer); 2421 2422 sk->sk_allocation = GFP_KERNEL; 2423 sk->sk_rcvbuf = sysctl_rmem_default; 2424 sk->sk_sndbuf = sysctl_wmem_default; 2425 sk->sk_state = TCP_CLOSE; 2426 sk_set_socket(sk, sock); 2427 2428 sock_set_flag(sk, SOCK_ZAPPED); 2429 2430 if (sock) { 2431 sk->sk_type = sock->type; 2432 sk->sk_wq = sock->wq; 2433 sock->sk = sk; 2434 } else 2435 sk->sk_wq = NULL; 2436 2437 rwlock_init(&sk->sk_callback_lock); 2438 lockdep_set_class_and_name(&sk->sk_callback_lock, 2439 af_callback_keys + sk->sk_family, 2440 af_family_clock_key_strings[sk->sk_family]); 2441 2442 sk->sk_state_change = sock_def_wakeup; 2443 sk->sk_data_ready = sock_def_readable; 2444 sk->sk_write_space = sock_def_write_space; 2445 sk->sk_error_report = sock_def_error_report; 2446 sk->sk_destruct = sock_def_destruct; 2447 2448 sk->sk_frag.page = NULL; 2449 sk->sk_frag.offset = 0; 2450 sk->sk_peek_off = -1; 2451 2452 sk->sk_peer_pid = NULL; 2453 sk->sk_peer_cred = NULL; 2454 sk->sk_write_pending = 0; 2455 sk->sk_rcvlowat = 1; 2456 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2457 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2458 2459 sk->sk_stamp = ktime_set(-1L, 0); 2460 2461 #ifdef CONFIG_NET_RX_BUSY_POLL 2462 sk->sk_napi_id = 0; 2463 sk->sk_ll_usec = sysctl_net_busy_read; 2464 #endif 2465 2466 sk->sk_max_pacing_rate = ~0U; 2467 sk->sk_pacing_rate = ~0U; 2468 sk->sk_incoming_cpu = -1; 2469 /* 2470 * Before updating sk_refcnt, we must commit prior changes to memory 2471 * (Documentation/RCU/rculist_nulls.txt for details) 2472 */ 2473 smp_wmb(); 2474 atomic_set(&sk->sk_refcnt, 1); 2475 atomic_set(&sk->sk_drops, 0); 2476 } 2477 EXPORT_SYMBOL(sock_init_data); 2478 2479 void lock_sock_nested(struct sock *sk, int subclass) 2480 { 2481 might_sleep(); 2482 spin_lock_bh(&sk->sk_lock.slock); 2483 if (sk->sk_lock.owned) 2484 __lock_sock(sk); 2485 sk->sk_lock.owned = 1; 2486 spin_unlock(&sk->sk_lock.slock); 2487 /* 2488 * The sk_lock has mutex_lock() semantics here: 2489 */ 2490 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2491 local_bh_enable(); 2492 } 2493 EXPORT_SYMBOL(lock_sock_nested); 2494 2495 void release_sock(struct sock *sk) 2496 { 2497 spin_lock_bh(&sk->sk_lock.slock); 2498 if (sk->sk_backlog.tail) 2499 __release_sock(sk); 2500 2501 /* Warning : release_cb() might need to release sk ownership, 2502 * ie call sock_release_ownership(sk) before us. 2503 */ 2504 if (sk->sk_prot->release_cb) 2505 sk->sk_prot->release_cb(sk); 2506 2507 sock_release_ownership(sk); 2508 if (waitqueue_active(&sk->sk_lock.wq)) 2509 wake_up(&sk->sk_lock.wq); 2510 spin_unlock_bh(&sk->sk_lock.slock); 2511 } 2512 EXPORT_SYMBOL(release_sock); 2513 2514 /** 2515 * lock_sock_fast - fast version of lock_sock 2516 * @sk: socket 2517 * 2518 * This version should be used for very small section, where process wont block 2519 * return false if fast path is taken 2520 * sk_lock.slock locked, owned = 0, BH disabled 2521 * return true if slow path is taken 2522 * sk_lock.slock unlocked, owned = 1, BH enabled 2523 */ 2524 bool lock_sock_fast(struct sock *sk) 2525 { 2526 might_sleep(); 2527 spin_lock_bh(&sk->sk_lock.slock); 2528 2529 if (!sk->sk_lock.owned) 2530 /* 2531 * Note : We must disable BH 2532 */ 2533 return false; 2534 2535 __lock_sock(sk); 2536 sk->sk_lock.owned = 1; 2537 spin_unlock(&sk->sk_lock.slock); 2538 /* 2539 * The sk_lock has mutex_lock() semantics here: 2540 */ 2541 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2542 local_bh_enable(); 2543 return true; 2544 } 2545 EXPORT_SYMBOL(lock_sock_fast); 2546 2547 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2548 { 2549 struct timeval tv; 2550 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2551 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2552 tv = ktime_to_timeval(sk->sk_stamp); 2553 if (tv.tv_sec == -1) 2554 return -ENOENT; 2555 if (tv.tv_sec == 0) { 2556 sk->sk_stamp = ktime_get_real(); 2557 tv = ktime_to_timeval(sk->sk_stamp); 2558 } 2559 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2560 } 2561 EXPORT_SYMBOL(sock_get_timestamp); 2562 2563 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2564 { 2565 struct timespec ts; 2566 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2567 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2568 ts = ktime_to_timespec(sk->sk_stamp); 2569 if (ts.tv_sec == -1) 2570 return -ENOENT; 2571 if (ts.tv_sec == 0) { 2572 sk->sk_stamp = ktime_get_real(); 2573 ts = ktime_to_timespec(sk->sk_stamp); 2574 } 2575 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2576 } 2577 EXPORT_SYMBOL(sock_get_timestampns); 2578 2579 void sock_enable_timestamp(struct sock *sk, int flag) 2580 { 2581 if (!sock_flag(sk, flag)) { 2582 unsigned long previous_flags = sk->sk_flags; 2583 2584 sock_set_flag(sk, flag); 2585 /* 2586 * we just set one of the two flags which require net 2587 * time stamping, but time stamping might have been on 2588 * already because of the other one 2589 */ 2590 if (sock_needs_netstamp(sk) && 2591 !(previous_flags & SK_FLAGS_TIMESTAMP)) 2592 net_enable_timestamp(); 2593 } 2594 } 2595 2596 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 2597 int level, int type) 2598 { 2599 struct sock_exterr_skb *serr; 2600 struct sk_buff *skb; 2601 int copied, err; 2602 2603 err = -EAGAIN; 2604 skb = sock_dequeue_err_skb(sk); 2605 if (skb == NULL) 2606 goto out; 2607 2608 copied = skb->len; 2609 if (copied > len) { 2610 msg->msg_flags |= MSG_TRUNC; 2611 copied = len; 2612 } 2613 err = skb_copy_datagram_msg(skb, 0, msg, copied); 2614 if (err) 2615 goto out_free_skb; 2616 2617 sock_recv_timestamp(msg, sk, skb); 2618 2619 serr = SKB_EXT_ERR(skb); 2620 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 2621 2622 msg->msg_flags |= MSG_ERRQUEUE; 2623 err = copied; 2624 2625 out_free_skb: 2626 kfree_skb(skb); 2627 out: 2628 return err; 2629 } 2630 EXPORT_SYMBOL(sock_recv_errqueue); 2631 2632 /* 2633 * Get a socket option on an socket. 2634 * 2635 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2636 * asynchronous errors should be reported by getsockopt. We assume 2637 * this means if you specify SO_ERROR (otherwise whats the point of it). 2638 */ 2639 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2640 char __user *optval, int __user *optlen) 2641 { 2642 struct sock *sk = sock->sk; 2643 2644 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2645 } 2646 EXPORT_SYMBOL(sock_common_getsockopt); 2647 2648 #ifdef CONFIG_COMPAT 2649 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2650 char __user *optval, int __user *optlen) 2651 { 2652 struct sock *sk = sock->sk; 2653 2654 if (sk->sk_prot->compat_getsockopt != NULL) 2655 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2656 optval, optlen); 2657 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2658 } 2659 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2660 #endif 2661 2662 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 2663 int flags) 2664 { 2665 struct sock *sk = sock->sk; 2666 int addr_len = 0; 2667 int err; 2668 2669 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, 2670 flags & ~MSG_DONTWAIT, &addr_len); 2671 if (err >= 0) 2672 msg->msg_namelen = addr_len; 2673 return err; 2674 } 2675 EXPORT_SYMBOL(sock_common_recvmsg); 2676 2677 /* 2678 * Set socket options on an inet socket. 2679 */ 2680 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2681 char __user *optval, unsigned int optlen) 2682 { 2683 struct sock *sk = sock->sk; 2684 2685 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2686 } 2687 EXPORT_SYMBOL(sock_common_setsockopt); 2688 2689 #ifdef CONFIG_COMPAT 2690 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2691 char __user *optval, unsigned int optlen) 2692 { 2693 struct sock *sk = sock->sk; 2694 2695 if (sk->sk_prot->compat_setsockopt != NULL) 2696 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2697 optval, optlen); 2698 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2699 } 2700 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2701 #endif 2702 2703 void sk_common_release(struct sock *sk) 2704 { 2705 if (sk->sk_prot->destroy) 2706 sk->sk_prot->destroy(sk); 2707 2708 /* 2709 * Observation: when sock_common_release is called, processes have 2710 * no access to socket. But net still has. 2711 * Step one, detach it from networking: 2712 * 2713 * A. Remove from hash tables. 2714 */ 2715 2716 sk->sk_prot->unhash(sk); 2717 2718 /* 2719 * In this point socket cannot receive new packets, but it is possible 2720 * that some packets are in flight because some CPU runs receiver and 2721 * did hash table lookup before we unhashed socket. They will achieve 2722 * receive queue and will be purged by socket destructor. 2723 * 2724 * Also we still have packets pending on receive queue and probably, 2725 * our own packets waiting in device queues. sock_destroy will drain 2726 * receive queue, but transmitted packets will delay socket destruction 2727 * until the last reference will be released. 2728 */ 2729 2730 sock_orphan(sk); 2731 2732 xfrm_sk_free_policy(sk); 2733 2734 sk_refcnt_debug_release(sk); 2735 2736 if (sk->sk_frag.page) { 2737 put_page(sk->sk_frag.page); 2738 sk->sk_frag.page = NULL; 2739 } 2740 2741 sock_put(sk); 2742 } 2743 EXPORT_SYMBOL(sk_common_release); 2744 2745 #ifdef CONFIG_PROC_FS 2746 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2747 struct prot_inuse { 2748 int val[PROTO_INUSE_NR]; 2749 }; 2750 2751 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2752 2753 #ifdef CONFIG_NET_NS 2754 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2755 { 2756 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2757 } 2758 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2759 2760 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2761 { 2762 int cpu, idx = prot->inuse_idx; 2763 int res = 0; 2764 2765 for_each_possible_cpu(cpu) 2766 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2767 2768 return res >= 0 ? res : 0; 2769 } 2770 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2771 2772 static int __net_init sock_inuse_init_net(struct net *net) 2773 { 2774 net->core.inuse = alloc_percpu(struct prot_inuse); 2775 return net->core.inuse ? 0 : -ENOMEM; 2776 } 2777 2778 static void __net_exit sock_inuse_exit_net(struct net *net) 2779 { 2780 free_percpu(net->core.inuse); 2781 } 2782 2783 static struct pernet_operations net_inuse_ops = { 2784 .init = sock_inuse_init_net, 2785 .exit = sock_inuse_exit_net, 2786 }; 2787 2788 static __init int net_inuse_init(void) 2789 { 2790 if (register_pernet_subsys(&net_inuse_ops)) 2791 panic("Cannot initialize net inuse counters"); 2792 2793 return 0; 2794 } 2795 2796 core_initcall(net_inuse_init); 2797 #else 2798 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2799 2800 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2801 { 2802 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2803 } 2804 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2805 2806 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2807 { 2808 int cpu, idx = prot->inuse_idx; 2809 int res = 0; 2810 2811 for_each_possible_cpu(cpu) 2812 res += per_cpu(prot_inuse, cpu).val[idx]; 2813 2814 return res >= 0 ? res : 0; 2815 } 2816 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2817 #endif 2818 2819 static void assign_proto_idx(struct proto *prot) 2820 { 2821 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2822 2823 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2824 pr_err("PROTO_INUSE_NR exhausted\n"); 2825 return; 2826 } 2827 2828 set_bit(prot->inuse_idx, proto_inuse_idx); 2829 } 2830 2831 static void release_proto_idx(struct proto *prot) 2832 { 2833 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2834 clear_bit(prot->inuse_idx, proto_inuse_idx); 2835 } 2836 #else 2837 static inline void assign_proto_idx(struct proto *prot) 2838 { 2839 } 2840 2841 static inline void release_proto_idx(struct proto *prot) 2842 { 2843 } 2844 #endif 2845 2846 static void req_prot_cleanup(struct request_sock_ops *rsk_prot) 2847 { 2848 if (!rsk_prot) 2849 return; 2850 kfree(rsk_prot->slab_name); 2851 rsk_prot->slab_name = NULL; 2852 kmem_cache_destroy(rsk_prot->slab); 2853 rsk_prot->slab = NULL; 2854 } 2855 2856 static int req_prot_init(const struct proto *prot) 2857 { 2858 struct request_sock_ops *rsk_prot = prot->rsk_prot; 2859 2860 if (!rsk_prot) 2861 return 0; 2862 2863 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", 2864 prot->name); 2865 if (!rsk_prot->slab_name) 2866 return -ENOMEM; 2867 2868 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name, 2869 rsk_prot->obj_size, 0, 2870 prot->slab_flags, NULL); 2871 2872 if (!rsk_prot->slab) { 2873 pr_crit("%s: Can't create request sock SLAB cache!\n", 2874 prot->name); 2875 return -ENOMEM; 2876 } 2877 return 0; 2878 } 2879 2880 int proto_register(struct proto *prot, int alloc_slab) 2881 { 2882 if (alloc_slab) { 2883 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2884 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2885 NULL); 2886 2887 if (prot->slab == NULL) { 2888 pr_crit("%s: Can't create sock SLAB cache!\n", 2889 prot->name); 2890 goto out; 2891 } 2892 2893 if (req_prot_init(prot)) 2894 goto out_free_request_sock_slab; 2895 2896 if (prot->twsk_prot != NULL) { 2897 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2898 2899 if (prot->twsk_prot->twsk_slab_name == NULL) 2900 goto out_free_request_sock_slab; 2901 2902 prot->twsk_prot->twsk_slab = 2903 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2904 prot->twsk_prot->twsk_obj_size, 2905 0, 2906 prot->slab_flags, 2907 NULL); 2908 if (prot->twsk_prot->twsk_slab == NULL) 2909 goto out_free_timewait_sock_slab_name; 2910 } 2911 } 2912 2913 mutex_lock(&proto_list_mutex); 2914 list_add(&prot->node, &proto_list); 2915 assign_proto_idx(prot); 2916 mutex_unlock(&proto_list_mutex); 2917 return 0; 2918 2919 out_free_timewait_sock_slab_name: 2920 kfree(prot->twsk_prot->twsk_slab_name); 2921 out_free_request_sock_slab: 2922 req_prot_cleanup(prot->rsk_prot); 2923 2924 kmem_cache_destroy(prot->slab); 2925 prot->slab = NULL; 2926 out: 2927 return -ENOBUFS; 2928 } 2929 EXPORT_SYMBOL(proto_register); 2930 2931 void proto_unregister(struct proto *prot) 2932 { 2933 mutex_lock(&proto_list_mutex); 2934 release_proto_idx(prot); 2935 list_del(&prot->node); 2936 mutex_unlock(&proto_list_mutex); 2937 2938 kmem_cache_destroy(prot->slab); 2939 prot->slab = NULL; 2940 2941 req_prot_cleanup(prot->rsk_prot); 2942 2943 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2944 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2945 kfree(prot->twsk_prot->twsk_slab_name); 2946 prot->twsk_prot->twsk_slab = NULL; 2947 } 2948 } 2949 EXPORT_SYMBOL(proto_unregister); 2950 2951 #ifdef CONFIG_PROC_FS 2952 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2953 __acquires(proto_list_mutex) 2954 { 2955 mutex_lock(&proto_list_mutex); 2956 return seq_list_start_head(&proto_list, *pos); 2957 } 2958 2959 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2960 { 2961 return seq_list_next(v, &proto_list, pos); 2962 } 2963 2964 static void proto_seq_stop(struct seq_file *seq, void *v) 2965 __releases(proto_list_mutex) 2966 { 2967 mutex_unlock(&proto_list_mutex); 2968 } 2969 2970 static char proto_method_implemented(const void *method) 2971 { 2972 return method == NULL ? 'n' : 'y'; 2973 } 2974 static long sock_prot_memory_allocated(struct proto *proto) 2975 { 2976 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 2977 } 2978 2979 static char *sock_prot_memory_pressure(struct proto *proto) 2980 { 2981 return proto->memory_pressure != NULL ? 2982 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 2983 } 2984 2985 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 2986 { 2987 2988 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 2989 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 2990 proto->name, 2991 proto->obj_size, 2992 sock_prot_inuse_get(seq_file_net(seq), proto), 2993 sock_prot_memory_allocated(proto), 2994 sock_prot_memory_pressure(proto), 2995 proto->max_header, 2996 proto->slab == NULL ? "no" : "yes", 2997 module_name(proto->owner), 2998 proto_method_implemented(proto->close), 2999 proto_method_implemented(proto->connect), 3000 proto_method_implemented(proto->disconnect), 3001 proto_method_implemented(proto->accept), 3002 proto_method_implemented(proto->ioctl), 3003 proto_method_implemented(proto->init), 3004 proto_method_implemented(proto->destroy), 3005 proto_method_implemented(proto->shutdown), 3006 proto_method_implemented(proto->setsockopt), 3007 proto_method_implemented(proto->getsockopt), 3008 proto_method_implemented(proto->sendmsg), 3009 proto_method_implemented(proto->recvmsg), 3010 proto_method_implemented(proto->sendpage), 3011 proto_method_implemented(proto->bind), 3012 proto_method_implemented(proto->backlog_rcv), 3013 proto_method_implemented(proto->hash), 3014 proto_method_implemented(proto->unhash), 3015 proto_method_implemented(proto->get_port), 3016 proto_method_implemented(proto->enter_memory_pressure)); 3017 } 3018 3019 static int proto_seq_show(struct seq_file *seq, void *v) 3020 { 3021 if (v == &proto_list) 3022 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 3023 "protocol", 3024 "size", 3025 "sockets", 3026 "memory", 3027 "press", 3028 "maxhdr", 3029 "slab", 3030 "module", 3031 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 3032 else 3033 proto_seq_printf(seq, list_entry(v, struct proto, node)); 3034 return 0; 3035 } 3036 3037 static const struct seq_operations proto_seq_ops = { 3038 .start = proto_seq_start, 3039 .next = proto_seq_next, 3040 .stop = proto_seq_stop, 3041 .show = proto_seq_show, 3042 }; 3043 3044 static int proto_seq_open(struct inode *inode, struct file *file) 3045 { 3046 return seq_open_net(inode, file, &proto_seq_ops, 3047 sizeof(struct seq_net_private)); 3048 } 3049 3050 static const struct file_operations proto_seq_fops = { 3051 .owner = THIS_MODULE, 3052 .open = proto_seq_open, 3053 .read = seq_read, 3054 .llseek = seq_lseek, 3055 .release = seq_release_net, 3056 }; 3057 3058 static __net_init int proto_init_net(struct net *net) 3059 { 3060 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops)) 3061 return -ENOMEM; 3062 3063 return 0; 3064 } 3065 3066 static __net_exit void proto_exit_net(struct net *net) 3067 { 3068 remove_proc_entry("protocols", net->proc_net); 3069 } 3070 3071 3072 static __net_initdata struct pernet_operations proto_net_ops = { 3073 .init = proto_init_net, 3074 .exit = proto_exit_net, 3075 }; 3076 3077 static int __init proto_init(void) 3078 { 3079 return register_pernet_subsys(&proto_net_ops); 3080 } 3081 3082 subsys_initcall(proto_init); 3083 3084 #endif /* PROC_FS */ 3085