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/types.h> 97 #include <linux/socket.h> 98 #include <linux/in.h> 99 #include <linux/kernel.h> 100 #include <linux/module.h> 101 #include <linux/proc_fs.h> 102 #include <linux/seq_file.h> 103 #include <linux/sched.h> 104 #include <linux/timer.h> 105 #include <linux/string.h> 106 #include <linux/sockios.h> 107 #include <linux/net.h> 108 #include <linux/mm.h> 109 #include <linux/slab.h> 110 #include <linux/interrupt.h> 111 #include <linux/poll.h> 112 #include <linux/tcp.h> 113 #include <linux/init.h> 114 #include <linux/highmem.h> 115 #include <linux/user_namespace.h> 116 #include <linux/static_key.h> 117 #include <linux/memcontrol.h> 118 #include <linux/prefetch.h> 119 120 #include <asm/uaccess.h> 121 122 #include <linux/netdevice.h> 123 #include <net/protocol.h> 124 #include <linux/skbuff.h> 125 #include <net/net_namespace.h> 126 #include <net/request_sock.h> 127 #include <net/sock.h> 128 #include <linux/net_tstamp.h> 129 #include <net/xfrm.h> 130 #include <linux/ipsec.h> 131 #include <net/cls_cgroup.h> 132 #include <net/netprio_cgroup.h> 133 134 #include <linux/filter.h> 135 136 #include <trace/events/sock.h> 137 138 #ifdef CONFIG_INET 139 #include <net/tcp.h> 140 #endif 141 142 static DEFINE_MUTEX(proto_list_mutex); 143 static LIST_HEAD(proto_list); 144 145 #ifdef CONFIG_MEMCG_KMEM 146 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss) 147 { 148 struct proto *proto; 149 int ret = 0; 150 151 mutex_lock(&proto_list_mutex); 152 list_for_each_entry(proto, &proto_list, node) { 153 if (proto->init_cgroup) { 154 ret = proto->init_cgroup(memcg, ss); 155 if (ret) 156 goto out; 157 } 158 } 159 160 mutex_unlock(&proto_list_mutex); 161 return ret; 162 out: 163 list_for_each_entry_continue_reverse(proto, &proto_list, node) 164 if (proto->destroy_cgroup) 165 proto->destroy_cgroup(memcg); 166 mutex_unlock(&proto_list_mutex); 167 return ret; 168 } 169 170 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg) 171 { 172 struct proto *proto; 173 174 mutex_lock(&proto_list_mutex); 175 list_for_each_entry_reverse(proto, &proto_list, node) 176 if (proto->destroy_cgroup) 177 proto->destroy_cgroup(memcg); 178 mutex_unlock(&proto_list_mutex); 179 } 180 #endif 181 182 /* 183 * Each address family might have different locking rules, so we have 184 * one slock key per address family: 185 */ 186 static struct lock_class_key af_family_keys[AF_MAX]; 187 static struct lock_class_key af_family_slock_keys[AF_MAX]; 188 189 struct static_key memcg_socket_limit_enabled; 190 EXPORT_SYMBOL(memcg_socket_limit_enabled); 191 192 /* 193 * Make lock validator output more readable. (we pre-construct these 194 * strings build-time, so that runtime initialization of socket 195 * locks is fast): 196 */ 197 static const char *const af_family_key_strings[AF_MAX+1] = { 198 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" , 199 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK", 200 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" , 201 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" , 202 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" , 203 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" , 204 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" , 205 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" , 206 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" , 207 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" , 208 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" , 209 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" , 210 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" , 211 "sk_lock-AF_NFC" , "sk_lock-AF_MAX" 212 }; 213 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 214 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" , 215 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK", 216 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" , 217 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" , 218 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" , 219 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" , 220 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" , 221 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" , 222 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" , 223 "slock-27" , "slock-28" , "slock-AF_CAN" , 224 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" , 225 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" , 226 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" , 227 "slock-AF_NFC" , "slock-AF_MAX" 228 }; 229 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 230 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" , 231 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK", 232 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" , 233 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" , 234 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" , 235 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" , 236 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" , 237 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" , 238 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" , 239 "clock-27" , "clock-28" , "clock-AF_CAN" , 240 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" , 241 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" , 242 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" , 243 "clock-AF_NFC" , "clock-AF_MAX" 244 }; 245 246 /* 247 * sk_callback_lock locking rules are per-address-family, 248 * so split the lock classes by using a per-AF key: 249 */ 250 static struct lock_class_key af_callback_keys[AF_MAX]; 251 252 /* Take into consideration the size of the struct sk_buff overhead in the 253 * determination of these values, since that is non-constant across 254 * platforms. This makes socket queueing behavior and performance 255 * not depend upon such differences. 256 */ 257 #define _SK_MEM_PACKETS 256 258 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 259 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 260 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 261 262 /* Run time adjustable parameters. */ 263 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 264 EXPORT_SYMBOL(sysctl_wmem_max); 265 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 266 EXPORT_SYMBOL(sysctl_rmem_max); 267 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 268 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 269 270 /* Maximal space eaten by iovec or ancillary data plus some space */ 271 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); 272 EXPORT_SYMBOL(sysctl_optmem_max); 273 274 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE; 275 EXPORT_SYMBOL_GPL(memalloc_socks); 276 277 /** 278 * sk_set_memalloc - sets %SOCK_MEMALLOC 279 * @sk: socket to set it on 280 * 281 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 282 * It's the responsibility of the admin to adjust min_free_kbytes 283 * to meet the requirements 284 */ 285 void sk_set_memalloc(struct sock *sk) 286 { 287 sock_set_flag(sk, SOCK_MEMALLOC); 288 sk->sk_allocation |= __GFP_MEMALLOC; 289 static_key_slow_inc(&memalloc_socks); 290 } 291 EXPORT_SYMBOL_GPL(sk_set_memalloc); 292 293 void sk_clear_memalloc(struct sock *sk) 294 { 295 sock_reset_flag(sk, SOCK_MEMALLOC); 296 sk->sk_allocation &= ~__GFP_MEMALLOC; 297 static_key_slow_dec(&memalloc_socks); 298 299 /* 300 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 301 * progress of swapping. However, if SOCK_MEMALLOC is cleared while 302 * it has rmem allocations there is a risk that the user of the 303 * socket cannot make forward progress due to exceeding the rmem 304 * limits. By rights, sk_clear_memalloc() should only be called 305 * on sockets being torn down but warn and reset the accounting if 306 * that assumption breaks. 307 */ 308 if (WARN_ON(sk->sk_forward_alloc)) 309 sk_mem_reclaim(sk); 310 } 311 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 312 313 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 314 { 315 int ret; 316 unsigned long pflags = current->flags; 317 318 /* these should have been dropped before queueing */ 319 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 320 321 current->flags |= PF_MEMALLOC; 322 ret = sk->sk_backlog_rcv(sk, skb); 323 tsk_restore_flags(current, pflags, PF_MEMALLOC); 324 325 return ret; 326 } 327 EXPORT_SYMBOL(__sk_backlog_rcv); 328 329 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen) 330 { 331 struct timeval tv; 332 333 if (optlen < sizeof(tv)) 334 return -EINVAL; 335 if (copy_from_user(&tv, optval, sizeof(tv))) 336 return -EFAULT; 337 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 338 return -EDOM; 339 340 if (tv.tv_sec < 0) { 341 static int warned __read_mostly; 342 343 *timeo_p = 0; 344 if (warned < 10 && net_ratelimit()) { 345 warned++; 346 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 347 __func__, current->comm, task_pid_nr(current)); 348 } 349 return 0; 350 } 351 *timeo_p = MAX_SCHEDULE_TIMEOUT; 352 if (tv.tv_sec == 0 && tv.tv_usec == 0) 353 return 0; 354 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1)) 355 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ); 356 return 0; 357 } 358 359 static void sock_warn_obsolete_bsdism(const char *name) 360 { 361 static int warned; 362 static char warncomm[TASK_COMM_LEN]; 363 if (strcmp(warncomm, current->comm) && warned < 5) { 364 strcpy(warncomm, current->comm); 365 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", 366 warncomm, name); 367 warned++; 368 } 369 } 370 371 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 372 373 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 374 { 375 if (sk->sk_flags & flags) { 376 sk->sk_flags &= ~flags; 377 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 378 net_disable_timestamp(); 379 } 380 } 381 382 383 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 384 { 385 int err; 386 int skb_len; 387 unsigned long flags; 388 struct sk_buff_head *list = &sk->sk_receive_queue; 389 390 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 391 atomic_inc(&sk->sk_drops); 392 trace_sock_rcvqueue_full(sk, skb); 393 return -ENOMEM; 394 } 395 396 err = sk_filter(sk, skb); 397 if (err) 398 return err; 399 400 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 401 atomic_inc(&sk->sk_drops); 402 return -ENOBUFS; 403 } 404 405 skb->dev = NULL; 406 skb_set_owner_r(skb, sk); 407 408 /* Cache the SKB length before we tack it onto the receive 409 * queue. Once it is added it no longer belongs to us and 410 * may be freed by other threads of control pulling packets 411 * from the queue. 412 */ 413 skb_len = skb->len; 414 415 /* we escape from rcu protected region, make sure we dont leak 416 * a norefcounted dst 417 */ 418 skb_dst_force(skb); 419 420 spin_lock_irqsave(&list->lock, flags); 421 skb->dropcount = atomic_read(&sk->sk_drops); 422 __skb_queue_tail(list, skb); 423 spin_unlock_irqrestore(&list->lock, flags); 424 425 if (!sock_flag(sk, SOCK_DEAD)) 426 sk->sk_data_ready(sk, skb_len); 427 return 0; 428 } 429 EXPORT_SYMBOL(sock_queue_rcv_skb); 430 431 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested) 432 { 433 int rc = NET_RX_SUCCESS; 434 435 if (sk_filter(sk, skb)) 436 goto discard_and_relse; 437 438 skb->dev = NULL; 439 440 if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) { 441 atomic_inc(&sk->sk_drops); 442 goto discard_and_relse; 443 } 444 if (nested) 445 bh_lock_sock_nested(sk); 446 else 447 bh_lock_sock(sk); 448 if (!sock_owned_by_user(sk)) { 449 /* 450 * trylock + unlock semantics: 451 */ 452 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 453 454 rc = sk_backlog_rcv(sk, skb); 455 456 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 457 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 458 bh_unlock_sock(sk); 459 atomic_inc(&sk->sk_drops); 460 goto discard_and_relse; 461 } 462 463 bh_unlock_sock(sk); 464 out: 465 sock_put(sk); 466 return rc; 467 discard_and_relse: 468 kfree_skb(skb); 469 goto out; 470 } 471 EXPORT_SYMBOL(sk_receive_skb); 472 473 void sk_reset_txq(struct sock *sk) 474 { 475 sk_tx_queue_clear(sk); 476 } 477 EXPORT_SYMBOL(sk_reset_txq); 478 479 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 480 { 481 struct dst_entry *dst = __sk_dst_get(sk); 482 483 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 484 sk_tx_queue_clear(sk); 485 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 486 dst_release(dst); 487 return NULL; 488 } 489 490 return dst; 491 } 492 EXPORT_SYMBOL(__sk_dst_check); 493 494 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 495 { 496 struct dst_entry *dst = sk_dst_get(sk); 497 498 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 499 sk_dst_reset(sk); 500 dst_release(dst); 501 return NULL; 502 } 503 504 return dst; 505 } 506 EXPORT_SYMBOL(sk_dst_check); 507 508 static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen) 509 { 510 int ret = -ENOPROTOOPT; 511 #ifdef CONFIG_NETDEVICES 512 struct net *net = sock_net(sk); 513 char devname[IFNAMSIZ]; 514 int index; 515 516 /* Sorry... */ 517 ret = -EPERM; 518 if (!capable(CAP_NET_RAW)) 519 goto out; 520 521 ret = -EINVAL; 522 if (optlen < 0) 523 goto out; 524 525 /* Bind this socket to a particular device like "eth0", 526 * as specified in the passed interface name. If the 527 * name is "" or the option length is zero the socket 528 * is not bound. 529 */ 530 if (optlen > IFNAMSIZ - 1) 531 optlen = IFNAMSIZ - 1; 532 memset(devname, 0, sizeof(devname)); 533 534 ret = -EFAULT; 535 if (copy_from_user(devname, optval, optlen)) 536 goto out; 537 538 index = 0; 539 if (devname[0] != '\0') { 540 struct net_device *dev; 541 542 rcu_read_lock(); 543 dev = dev_get_by_name_rcu(net, devname); 544 if (dev) 545 index = dev->ifindex; 546 rcu_read_unlock(); 547 ret = -ENODEV; 548 if (!dev) 549 goto out; 550 } 551 552 lock_sock(sk); 553 sk->sk_bound_dev_if = index; 554 sk_dst_reset(sk); 555 release_sock(sk); 556 557 ret = 0; 558 559 out: 560 #endif 561 562 return ret; 563 } 564 565 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) 566 { 567 if (valbool) 568 sock_set_flag(sk, bit); 569 else 570 sock_reset_flag(sk, bit); 571 } 572 573 /* 574 * This is meant for all protocols to use and covers goings on 575 * at the socket level. Everything here is generic. 576 */ 577 578 int sock_setsockopt(struct socket *sock, int level, int optname, 579 char __user *optval, unsigned int optlen) 580 { 581 struct sock *sk = sock->sk; 582 int val; 583 int valbool; 584 struct linger ling; 585 int ret = 0; 586 587 /* 588 * Options without arguments 589 */ 590 591 if (optname == SO_BINDTODEVICE) 592 return sock_bindtodevice(sk, optval, optlen); 593 594 if (optlen < sizeof(int)) 595 return -EINVAL; 596 597 if (get_user(val, (int __user *)optval)) 598 return -EFAULT; 599 600 valbool = val ? 1 : 0; 601 602 lock_sock(sk); 603 604 switch (optname) { 605 case SO_DEBUG: 606 if (val && !capable(CAP_NET_ADMIN)) 607 ret = -EACCES; 608 else 609 sock_valbool_flag(sk, SOCK_DBG, valbool); 610 break; 611 case SO_REUSEADDR: 612 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 613 break; 614 case SO_TYPE: 615 case SO_PROTOCOL: 616 case SO_DOMAIN: 617 case SO_ERROR: 618 ret = -ENOPROTOOPT; 619 break; 620 case SO_DONTROUTE: 621 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 622 break; 623 case SO_BROADCAST: 624 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 625 break; 626 case SO_SNDBUF: 627 /* Don't error on this BSD doesn't and if you think 628 * about it this is right. Otherwise apps have to 629 * play 'guess the biggest size' games. RCVBUF/SNDBUF 630 * are treated in BSD as hints 631 */ 632 val = min_t(u32, val, sysctl_wmem_max); 633 set_sndbuf: 634 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 635 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF); 636 /* Wake up sending tasks if we upped the value. */ 637 sk->sk_write_space(sk); 638 break; 639 640 case SO_SNDBUFFORCE: 641 if (!capable(CAP_NET_ADMIN)) { 642 ret = -EPERM; 643 break; 644 } 645 goto set_sndbuf; 646 647 case SO_RCVBUF: 648 /* Don't error on this BSD doesn't and if you think 649 * about it this is right. Otherwise apps have to 650 * play 'guess the biggest size' games. RCVBUF/SNDBUF 651 * are treated in BSD as hints 652 */ 653 val = min_t(u32, val, sysctl_rmem_max); 654 set_rcvbuf: 655 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 656 /* 657 * We double it on the way in to account for 658 * "struct sk_buff" etc. overhead. Applications 659 * assume that the SO_RCVBUF setting they make will 660 * allow that much actual data to be received on that 661 * socket. 662 * 663 * Applications are unaware that "struct sk_buff" and 664 * other overheads allocate from the receive buffer 665 * during socket buffer allocation. 666 * 667 * And after considering the possible alternatives, 668 * returning the value we actually used in getsockopt 669 * is the most desirable behavior. 670 */ 671 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF); 672 break; 673 674 case SO_RCVBUFFORCE: 675 if (!capable(CAP_NET_ADMIN)) { 676 ret = -EPERM; 677 break; 678 } 679 goto set_rcvbuf; 680 681 case SO_KEEPALIVE: 682 #ifdef CONFIG_INET 683 if (sk->sk_protocol == IPPROTO_TCP && 684 sk->sk_type == SOCK_STREAM) 685 tcp_set_keepalive(sk, valbool); 686 #endif 687 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 688 break; 689 690 case SO_OOBINLINE: 691 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 692 break; 693 694 case SO_NO_CHECK: 695 sk->sk_no_check = valbool; 696 break; 697 698 case SO_PRIORITY: 699 if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN)) 700 sk->sk_priority = val; 701 else 702 ret = -EPERM; 703 break; 704 705 case SO_LINGER: 706 if (optlen < sizeof(ling)) { 707 ret = -EINVAL; /* 1003.1g */ 708 break; 709 } 710 if (copy_from_user(&ling, optval, sizeof(ling))) { 711 ret = -EFAULT; 712 break; 713 } 714 if (!ling.l_onoff) 715 sock_reset_flag(sk, SOCK_LINGER); 716 else { 717 #if (BITS_PER_LONG == 32) 718 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 719 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 720 else 721 #endif 722 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 723 sock_set_flag(sk, SOCK_LINGER); 724 } 725 break; 726 727 case SO_BSDCOMPAT: 728 sock_warn_obsolete_bsdism("setsockopt"); 729 break; 730 731 case SO_PASSCRED: 732 if (valbool) 733 set_bit(SOCK_PASSCRED, &sock->flags); 734 else 735 clear_bit(SOCK_PASSCRED, &sock->flags); 736 break; 737 738 case SO_TIMESTAMP: 739 case SO_TIMESTAMPNS: 740 if (valbool) { 741 if (optname == SO_TIMESTAMP) 742 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 743 else 744 sock_set_flag(sk, SOCK_RCVTSTAMPNS); 745 sock_set_flag(sk, SOCK_RCVTSTAMP); 746 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 747 } else { 748 sock_reset_flag(sk, SOCK_RCVTSTAMP); 749 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 750 } 751 break; 752 753 case SO_TIMESTAMPING: 754 if (val & ~SOF_TIMESTAMPING_MASK) { 755 ret = -EINVAL; 756 break; 757 } 758 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE, 759 val & SOF_TIMESTAMPING_TX_HARDWARE); 760 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE, 761 val & SOF_TIMESTAMPING_TX_SOFTWARE); 762 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE, 763 val & SOF_TIMESTAMPING_RX_HARDWARE); 764 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 765 sock_enable_timestamp(sk, 766 SOCK_TIMESTAMPING_RX_SOFTWARE); 767 else 768 sock_disable_timestamp(sk, 769 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 770 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE, 771 val & SOF_TIMESTAMPING_SOFTWARE); 772 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE, 773 val & SOF_TIMESTAMPING_SYS_HARDWARE); 774 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE, 775 val & SOF_TIMESTAMPING_RAW_HARDWARE); 776 break; 777 778 case SO_RCVLOWAT: 779 if (val < 0) 780 val = INT_MAX; 781 sk->sk_rcvlowat = val ? : 1; 782 break; 783 784 case SO_RCVTIMEO: 785 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); 786 break; 787 788 case SO_SNDTIMEO: 789 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); 790 break; 791 792 case SO_ATTACH_FILTER: 793 ret = -EINVAL; 794 if (optlen == sizeof(struct sock_fprog)) { 795 struct sock_fprog fprog; 796 797 ret = -EFAULT; 798 if (copy_from_user(&fprog, optval, sizeof(fprog))) 799 break; 800 801 ret = sk_attach_filter(&fprog, sk); 802 } 803 break; 804 805 case SO_DETACH_FILTER: 806 ret = sk_detach_filter(sk); 807 break; 808 809 case SO_PASSSEC: 810 if (valbool) 811 set_bit(SOCK_PASSSEC, &sock->flags); 812 else 813 clear_bit(SOCK_PASSSEC, &sock->flags); 814 break; 815 case SO_MARK: 816 if (!capable(CAP_NET_ADMIN)) 817 ret = -EPERM; 818 else 819 sk->sk_mark = val; 820 break; 821 822 /* We implement the SO_SNDLOWAT etc to 823 not be settable (1003.1g 5.3) */ 824 case SO_RXQ_OVFL: 825 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 826 break; 827 828 case SO_WIFI_STATUS: 829 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 830 break; 831 832 case SO_PEEK_OFF: 833 if (sock->ops->set_peek_off) 834 sock->ops->set_peek_off(sk, val); 835 else 836 ret = -EOPNOTSUPP; 837 break; 838 839 case SO_NOFCS: 840 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 841 break; 842 843 default: 844 ret = -ENOPROTOOPT; 845 break; 846 } 847 release_sock(sk); 848 return ret; 849 } 850 EXPORT_SYMBOL(sock_setsockopt); 851 852 853 void cred_to_ucred(struct pid *pid, const struct cred *cred, 854 struct ucred *ucred) 855 { 856 ucred->pid = pid_vnr(pid); 857 ucred->uid = ucred->gid = -1; 858 if (cred) { 859 struct user_namespace *current_ns = current_user_ns(); 860 861 ucred->uid = from_kuid_munged(current_ns, cred->euid); 862 ucred->gid = from_kgid_munged(current_ns, cred->egid); 863 } 864 } 865 EXPORT_SYMBOL_GPL(cred_to_ucred); 866 867 int sock_getsockopt(struct socket *sock, int level, int optname, 868 char __user *optval, int __user *optlen) 869 { 870 struct sock *sk = sock->sk; 871 872 union { 873 int val; 874 struct linger ling; 875 struct timeval tm; 876 } v; 877 878 int lv = sizeof(int); 879 int len; 880 881 if (get_user(len, optlen)) 882 return -EFAULT; 883 if (len < 0) 884 return -EINVAL; 885 886 memset(&v, 0, sizeof(v)); 887 888 switch (optname) { 889 case SO_DEBUG: 890 v.val = sock_flag(sk, SOCK_DBG); 891 break; 892 893 case SO_DONTROUTE: 894 v.val = sock_flag(sk, SOCK_LOCALROUTE); 895 break; 896 897 case SO_BROADCAST: 898 v.val = sock_flag(sk, SOCK_BROADCAST); 899 break; 900 901 case SO_SNDBUF: 902 v.val = sk->sk_sndbuf; 903 break; 904 905 case SO_RCVBUF: 906 v.val = sk->sk_rcvbuf; 907 break; 908 909 case SO_REUSEADDR: 910 v.val = sk->sk_reuse; 911 break; 912 913 case SO_KEEPALIVE: 914 v.val = sock_flag(sk, SOCK_KEEPOPEN); 915 break; 916 917 case SO_TYPE: 918 v.val = sk->sk_type; 919 break; 920 921 case SO_PROTOCOL: 922 v.val = sk->sk_protocol; 923 break; 924 925 case SO_DOMAIN: 926 v.val = sk->sk_family; 927 break; 928 929 case SO_ERROR: 930 v.val = -sock_error(sk); 931 if (v.val == 0) 932 v.val = xchg(&sk->sk_err_soft, 0); 933 break; 934 935 case SO_OOBINLINE: 936 v.val = sock_flag(sk, SOCK_URGINLINE); 937 break; 938 939 case SO_NO_CHECK: 940 v.val = sk->sk_no_check; 941 break; 942 943 case SO_PRIORITY: 944 v.val = sk->sk_priority; 945 break; 946 947 case SO_LINGER: 948 lv = sizeof(v.ling); 949 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 950 v.ling.l_linger = sk->sk_lingertime / HZ; 951 break; 952 953 case SO_BSDCOMPAT: 954 sock_warn_obsolete_bsdism("getsockopt"); 955 break; 956 957 case SO_TIMESTAMP: 958 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 959 !sock_flag(sk, SOCK_RCVTSTAMPNS); 960 break; 961 962 case SO_TIMESTAMPNS: 963 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 964 break; 965 966 case SO_TIMESTAMPING: 967 v.val = 0; 968 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE)) 969 v.val |= SOF_TIMESTAMPING_TX_HARDWARE; 970 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE)) 971 v.val |= SOF_TIMESTAMPING_TX_SOFTWARE; 972 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE)) 973 v.val |= SOF_TIMESTAMPING_RX_HARDWARE; 974 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE)) 975 v.val |= SOF_TIMESTAMPING_RX_SOFTWARE; 976 if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) 977 v.val |= SOF_TIMESTAMPING_SOFTWARE; 978 if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)) 979 v.val |= SOF_TIMESTAMPING_SYS_HARDWARE; 980 if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) 981 v.val |= SOF_TIMESTAMPING_RAW_HARDWARE; 982 break; 983 984 case SO_RCVTIMEO: 985 lv = sizeof(struct timeval); 986 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 987 v.tm.tv_sec = 0; 988 v.tm.tv_usec = 0; 989 } else { 990 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 991 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 992 } 993 break; 994 995 case SO_SNDTIMEO: 996 lv = sizeof(struct timeval); 997 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 998 v.tm.tv_sec = 0; 999 v.tm.tv_usec = 0; 1000 } else { 1001 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1002 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1003 } 1004 break; 1005 1006 case SO_RCVLOWAT: 1007 v.val = sk->sk_rcvlowat; 1008 break; 1009 1010 case SO_SNDLOWAT: 1011 v.val = 1; 1012 break; 1013 1014 case SO_PASSCRED: 1015 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1016 break; 1017 1018 case SO_PEERCRED: 1019 { 1020 struct ucred peercred; 1021 if (len > sizeof(peercred)) 1022 len = sizeof(peercred); 1023 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1024 if (copy_to_user(optval, &peercred, len)) 1025 return -EFAULT; 1026 goto lenout; 1027 } 1028 1029 case SO_PEERNAME: 1030 { 1031 char address[128]; 1032 1033 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1034 return -ENOTCONN; 1035 if (lv < len) 1036 return -EINVAL; 1037 if (copy_to_user(optval, address, len)) 1038 return -EFAULT; 1039 goto lenout; 1040 } 1041 1042 /* Dubious BSD thing... Probably nobody even uses it, but 1043 * the UNIX standard wants it for whatever reason... -DaveM 1044 */ 1045 case SO_ACCEPTCONN: 1046 v.val = sk->sk_state == TCP_LISTEN; 1047 break; 1048 1049 case SO_PASSSEC: 1050 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1051 break; 1052 1053 case SO_PEERSEC: 1054 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1055 1056 case SO_MARK: 1057 v.val = sk->sk_mark; 1058 break; 1059 1060 case SO_RXQ_OVFL: 1061 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1062 break; 1063 1064 case SO_WIFI_STATUS: 1065 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1066 break; 1067 1068 case SO_PEEK_OFF: 1069 if (!sock->ops->set_peek_off) 1070 return -EOPNOTSUPP; 1071 1072 v.val = sk->sk_peek_off; 1073 break; 1074 case SO_NOFCS: 1075 v.val = sock_flag(sk, SOCK_NOFCS); 1076 break; 1077 default: 1078 return -ENOPROTOOPT; 1079 } 1080 1081 if (len > lv) 1082 len = lv; 1083 if (copy_to_user(optval, &v, len)) 1084 return -EFAULT; 1085 lenout: 1086 if (put_user(len, optlen)) 1087 return -EFAULT; 1088 return 0; 1089 } 1090 1091 /* 1092 * Initialize an sk_lock. 1093 * 1094 * (We also register the sk_lock with the lock validator.) 1095 */ 1096 static inline void sock_lock_init(struct sock *sk) 1097 { 1098 sock_lock_init_class_and_name(sk, 1099 af_family_slock_key_strings[sk->sk_family], 1100 af_family_slock_keys + sk->sk_family, 1101 af_family_key_strings[sk->sk_family], 1102 af_family_keys + sk->sk_family); 1103 } 1104 1105 /* 1106 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1107 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1108 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1109 */ 1110 static void sock_copy(struct sock *nsk, const struct sock *osk) 1111 { 1112 #ifdef CONFIG_SECURITY_NETWORK 1113 void *sptr = nsk->sk_security; 1114 #endif 1115 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1116 1117 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1118 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1119 1120 #ifdef CONFIG_SECURITY_NETWORK 1121 nsk->sk_security = sptr; 1122 security_sk_clone(osk, nsk); 1123 #endif 1124 } 1125 1126 /* 1127 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes 1128 * un-modified. Special care is taken when initializing object to zero. 1129 */ 1130 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1131 { 1132 if (offsetof(struct sock, sk_node.next) != 0) 1133 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1134 memset(&sk->sk_node.pprev, 0, 1135 size - offsetof(struct sock, sk_node.pprev)); 1136 } 1137 1138 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size) 1139 { 1140 unsigned long nulls1, nulls2; 1141 1142 nulls1 = offsetof(struct sock, __sk_common.skc_node.next); 1143 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next); 1144 if (nulls1 > nulls2) 1145 swap(nulls1, nulls2); 1146 1147 if (nulls1 != 0) 1148 memset((char *)sk, 0, nulls1); 1149 memset((char *)sk + nulls1 + sizeof(void *), 0, 1150 nulls2 - nulls1 - sizeof(void *)); 1151 memset((char *)sk + nulls2 + sizeof(void *), 0, 1152 size - nulls2 - sizeof(void *)); 1153 } 1154 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls); 1155 1156 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1157 int family) 1158 { 1159 struct sock *sk; 1160 struct kmem_cache *slab; 1161 1162 slab = prot->slab; 1163 if (slab != NULL) { 1164 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1165 if (!sk) 1166 return sk; 1167 if (priority & __GFP_ZERO) { 1168 if (prot->clear_sk) 1169 prot->clear_sk(sk, prot->obj_size); 1170 else 1171 sk_prot_clear_nulls(sk, prot->obj_size); 1172 } 1173 } else 1174 sk = kmalloc(prot->obj_size, priority); 1175 1176 if (sk != NULL) { 1177 kmemcheck_annotate_bitfield(sk, flags); 1178 1179 if (security_sk_alloc(sk, family, priority)) 1180 goto out_free; 1181 1182 if (!try_module_get(prot->owner)) 1183 goto out_free_sec; 1184 sk_tx_queue_clear(sk); 1185 } 1186 1187 return sk; 1188 1189 out_free_sec: 1190 security_sk_free(sk); 1191 out_free: 1192 if (slab != NULL) 1193 kmem_cache_free(slab, sk); 1194 else 1195 kfree(sk); 1196 return NULL; 1197 } 1198 1199 static void sk_prot_free(struct proto *prot, struct sock *sk) 1200 { 1201 struct kmem_cache *slab; 1202 struct module *owner; 1203 1204 owner = prot->owner; 1205 slab = prot->slab; 1206 1207 security_sk_free(sk); 1208 if (slab != NULL) 1209 kmem_cache_free(slab, sk); 1210 else 1211 kfree(sk); 1212 module_put(owner); 1213 } 1214 1215 #ifdef CONFIG_CGROUPS 1216 #if IS_ENABLED(CONFIG_NET_CLS_CGROUP) 1217 void sock_update_classid(struct sock *sk) 1218 { 1219 u32 classid; 1220 1221 rcu_read_lock(); /* doing current task, which cannot vanish. */ 1222 classid = task_cls_classid(current); 1223 rcu_read_unlock(); 1224 if (classid != sk->sk_classid) 1225 sk->sk_classid = classid; 1226 } 1227 EXPORT_SYMBOL(sock_update_classid); 1228 #endif 1229 1230 #if IS_ENABLED(CONFIG_NETPRIO_CGROUP) 1231 void sock_update_netprioidx(struct sock *sk, struct task_struct *task) 1232 { 1233 if (in_interrupt()) 1234 return; 1235 1236 sk->sk_cgrp_prioidx = task_netprioidx(task); 1237 } 1238 EXPORT_SYMBOL_GPL(sock_update_netprioidx); 1239 #endif 1240 #endif 1241 1242 /** 1243 * sk_alloc - All socket objects are allocated here 1244 * @net: the applicable net namespace 1245 * @family: protocol family 1246 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1247 * @prot: struct proto associated with this new sock instance 1248 */ 1249 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1250 struct proto *prot) 1251 { 1252 struct sock *sk; 1253 1254 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1255 if (sk) { 1256 sk->sk_family = family; 1257 /* 1258 * See comment in struct sock definition to understand 1259 * why we need sk_prot_creator -acme 1260 */ 1261 sk->sk_prot = sk->sk_prot_creator = prot; 1262 sock_lock_init(sk); 1263 sock_net_set(sk, get_net(net)); 1264 atomic_set(&sk->sk_wmem_alloc, 1); 1265 1266 sock_update_classid(sk); 1267 sock_update_netprioidx(sk, current); 1268 } 1269 1270 return sk; 1271 } 1272 EXPORT_SYMBOL(sk_alloc); 1273 1274 static void __sk_free(struct sock *sk) 1275 { 1276 struct sk_filter *filter; 1277 1278 if (sk->sk_destruct) 1279 sk->sk_destruct(sk); 1280 1281 filter = rcu_dereference_check(sk->sk_filter, 1282 atomic_read(&sk->sk_wmem_alloc) == 0); 1283 if (filter) { 1284 sk_filter_uncharge(sk, filter); 1285 RCU_INIT_POINTER(sk->sk_filter, NULL); 1286 } 1287 1288 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1289 1290 if (atomic_read(&sk->sk_omem_alloc)) 1291 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1292 __func__, atomic_read(&sk->sk_omem_alloc)); 1293 1294 if (sk->sk_peer_cred) 1295 put_cred(sk->sk_peer_cred); 1296 put_pid(sk->sk_peer_pid); 1297 put_net(sock_net(sk)); 1298 sk_prot_free(sk->sk_prot_creator, sk); 1299 } 1300 1301 void sk_free(struct sock *sk) 1302 { 1303 /* 1304 * We subtract one from sk_wmem_alloc and can know if 1305 * some packets are still in some tx queue. 1306 * If not null, sock_wfree() will call __sk_free(sk) later 1307 */ 1308 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1309 __sk_free(sk); 1310 } 1311 EXPORT_SYMBOL(sk_free); 1312 1313 /* 1314 * Last sock_put should drop reference to sk->sk_net. It has already 1315 * been dropped in sk_change_net. Taking reference to stopping namespace 1316 * is not an option. 1317 * Take reference to a socket to remove it from hash _alive_ and after that 1318 * destroy it in the context of init_net. 1319 */ 1320 void sk_release_kernel(struct sock *sk) 1321 { 1322 if (sk == NULL || sk->sk_socket == NULL) 1323 return; 1324 1325 sock_hold(sk); 1326 sock_release(sk->sk_socket); 1327 release_net(sock_net(sk)); 1328 sock_net_set(sk, get_net(&init_net)); 1329 sock_put(sk); 1330 } 1331 EXPORT_SYMBOL(sk_release_kernel); 1332 1333 static void sk_update_clone(const struct sock *sk, struct sock *newsk) 1334 { 1335 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1336 sock_update_memcg(newsk); 1337 } 1338 1339 /** 1340 * sk_clone_lock - clone a socket, and lock its clone 1341 * @sk: the socket to clone 1342 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1343 * 1344 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1345 */ 1346 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1347 { 1348 struct sock *newsk; 1349 1350 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1351 if (newsk != NULL) { 1352 struct sk_filter *filter; 1353 1354 sock_copy(newsk, sk); 1355 1356 /* SANITY */ 1357 get_net(sock_net(newsk)); 1358 sk_node_init(&newsk->sk_node); 1359 sock_lock_init(newsk); 1360 bh_lock_sock(newsk); 1361 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1362 newsk->sk_backlog.len = 0; 1363 1364 atomic_set(&newsk->sk_rmem_alloc, 0); 1365 /* 1366 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1367 */ 1368 atomic_set(&newsk->sk_wmem_alloc, 1); 1369 atomic_set(&newsk->sk_omem_alloc, 0); 1370 skb_queue_head_init(&newsk->sk_receive_queue); 1371 skb_queue_head_init(&newsk->sk_write_queue); 1372 #ifdef CONFIG_NET_DMA 1373 skb_queue_head_init(&newsk->sk_async_wait_queue); 1374 #endif 1375 1376 spin_lock_init(&newsk->sk_dst_lock); 1377 rwlock_init(&newsk->sk_callback_lock); 1378 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1379 af_callback_keys + newsk->sk_family, 1380 af_family_clock_key_strings[newsk->sk_family]); 1381 1382 newsk->sk_dst_cache = NULL; 1383 newsk->sk_wmem_queued = 0; 1384 newsk->sk_forward_alloc = 0; 1385 newsk->sk_send_head = NULL; 1386 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1387 1388 sock_reset_flag(newsk, SOCK_DONE); 1389 skb_queue_head_init(&newsk->sk_error_queue); 1390 1391 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1392 if (filter != NULL) 1393 sk_filter_charge(newsk, filter); 1394 1395 if (unlikely(xfrm_sk_clone_policy(newsk))) { 1396 /* It is still raw copy of parent, so invalidate 1397 * destructor and make plain sk_free() */ 1398 newsk->sk_destruct = NULL; 1399 bh_unlock_sock(newsk); 1400 sk_free(newsk); 1401 newsk = NULL; 1402 goto out; 1403 } 1404 1405 newsk->sk_err = 0; 1406 newsk->sk_priority = 0; 1407 /* 1408 * Before updating sk_refcnt, we must commit prior changes to memory 1409 * (Documentation/RCU/rculist_nulls.txt for details) 1410 */ 1411 smp_wmb(); 1412 atomic_set(&newsk->sk_refcnt, 2); 1413 1414 /* 1415 * Increment the counter in the same struct proto as the master 1416 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1417 * is the same as sk->sk_prot->socks, as this field was copied 1418 * with memcpy). 1419 * 1420 * This _changes_ the previous behaviour, where 1421 * tcp_create_openreq_child always was incrementing the 1422 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1423 * to be taken into account in all callers. -acme 1424 */ 1425 sk_refcnt_debug_inc(newsk); 1426 sk_set_socket(newsk, NULL); 1427 newsk->sk_wq = NULL; 1428 1429 sk_update_clone(sk, newsk); 1430 1431 if (newsk->sk_prot->sockets_allocated) 1432 sk_sockets_allocated_inc(newsk); 1433 1434 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1435 net_enable_timestamp(); 1436 } 1437 out: 1438 return newsk; 1439 } 1440 EXPORT_SYMBOL_GPL(sk_clone_lock); 1441 1442 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1443 { 1444 __sk_dst_set(sk, dst); 1445 sk->sk_route_caps = dst->dev->features; 1446 if (sk->sk_route_caps & NETIF_F_GSO) 1447 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1448 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1449 if (sk_can_gso(sk)) { 1450 if (dst->header_len) { 1451 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1452 } else { 1453 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1454 sk->sk_gso_max_size = dst->dev->gso_max_size; 1455 sk->sk_gso_max_segs = dst->dev->gso_max_segs; 1456 } 1457 } 1458 } 1459 EXPORT_SYMBOL_GPL(sk_setup_caps); 1460 1461 /* 1462 * Simple resource managers for sockets. 1463 */ 1464 1465 1466 /* 1467 * Write buffer destructor automatically called from kfree_skb. 1468 */ 1469 void sock_wfree(struct sk_buff *skb) 1470 { 1471 struct sock *sk = skb->sk; 1472 unsigned int len = skb->truesize; 1473 1474 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1475 /* 1476 * Keep a reference on sk_wmem_alloc, this will be released 1477 * after sk_write_space() call 1478 */ 1479 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1480 sk->sk_write_space(sk); 1481 len = 1; 1482 } 1483 /* 1484 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1485 * could not do because of in-flight packets 1486 */ 1487 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1488 __sk_free(sk); 1489 } 1490 EXPORT_SYMBOL(sock_wfree); 1491 1492 /* 1493 * Read buffer destructor automatically called from kfree_skb. 1494 */ 1495 void sock_rfree(struct sk_buff *skb) 1496 { 1497 struct sock *sk = skb->sk; 1498 unsigned int len = skb->truesize; 1499 1500 atomic_sub(len, &sk->sk_rmem_alloc); 1501 sk_mem_uncharge(sk, len); 1502 } 1503 EXPORT_SYMBOL(sock_rfree); 1504 1505 void sock_edemux(struct sk_buff *skb) 1506 { 1507 struct sock *sk = skb->sk; 1508 1509 #ifdef CONFIG_INET 1510 if (sk->sk_state == TCP_TIME_WAIT) 1511 inet_twsk_put(inet_twsk(sk)); 1512 else 1513 #endif 1514 sock_put(sk); 1515 } 1516 EXPORT_SYMBOL(sock_edemux); 1517 1518 kuid_t sock_i_uid(struct sock *sk) 1519 { 1520 kuid_t uid; 1521 1522 read_lock_bh(&sk->sk_callback_lock); 1523 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1524 read_unlock_bh(&sk->sk_callback_lock); 1525 return uid; 1526 } 1527 EXPORT_SYMBOL(sock_i_uid); 1528 1529 unsigned long sock_i_ino(struct sock *sk) 1530 { 1531 unsigned long ino; 1532 1533 read_lock_bh(&sk->sk_callback_lock); 1534 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1535 read_unlock_bh(&sk->sk_callback_lock); 1536 return ino; 1537 } 1538 EXPORT_SYMBOL(sock_i_ino); 1539 1540 /* 1541 * Allocate a skb from the socket's send buffer. 1542 */ 1543 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1544 gfp_t priority) 1545 { 1546 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1547 struct sk_buff *skb = alloc_skb(size, priority); 1548 if (skb) { 1549 skb_set_owner_w(skb, sk); 1550 return skb; 1551 } 1552 } 1553 return NULL; 1554 } 1555 EXPORT_SYMBOL(sock_wmalloc); 1556 1557 /* 1558 * Allocate a skb from the socket's receive buffer. 1559 */ 1560 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force, 1561 gfp_t priority) 1562 { 1563 if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) { 1564 struct sk_buff *skb = alloc_skb(size, priority); 1565 if (skb) { 1566 skb_set_owner_r(skb, sk); 1567 return skb; 1568 } 1569 } 1570 return NULL; 1571 } 1572 1573 /* 1574 * Allocate a memory block from the socket's option memory buffer. 1575 */ 1576 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1577 { 1578 if ((unsigned int)size <= sysctl_optmem_max && 1579 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1580 void *mem; 1581 /* First do the add, to avoid the race if kmalloc 1582 * might sleep. 1583 */ 1584 atomic_add(size, &sk->sk_omem_alloc); 1585 mem = kmalloc(size, priority); 1586 if (mem) 1587 return mem; 1588 atomic_sub(size, &sk->sk_omem_alloc); 1589 } 1590 return NULL; 1591 } 1592 EXPORT_SYMBOL(sock_kmalloc); 1593 1594 /* 1595 * Free an option memory block. 1596 */ 1597 void sock_kfree_s(struct sock *sk, void *mem, int size) 1598 { 1599 kfree(mem); 1600 atomic_sub(size, &sk->sk_omem_alloc); 1601 } 1602 EXPORT_SYMBOL(sock_kfree_s); 1603 1604 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1605 I think, these locks should be removed for datagram sockets. 1606 */ 1607 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1608 { 1609 DEFINE_WAIT(wait); 1610 1611 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1612 for (;;) { 1613 if (!timeo) 1614 break; 1615 if (signal_pending(current)) 1616 break; 1617 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1618 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1619 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1620 break; 1621 if (sk->sk_shutdown & SEND_SHUTDOWN) 1622 break; 1623 if (sk->sk_err) 1624 break; 1625 timeo = schedule_timeout(timeo); 1626 } 1627 finish_wait(sk_sleep(sk), &wait); 1628 return timeo; 1629 } 1630 1631 1632 /* 1633 * Generic send/receive buffer handlers 1634 */ 1635 1636 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1637 unsigned long data_len, int noblock, 1638 int *errcode) 1639 { 1640 struct sk_buff *skb; 1641 gfp_t gfp_mask; 1642 long timeo; 1643 int err; 1644 int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT; 1645 1646 err = -EMSGSIZE; 1647 if (npages > MAX_SKB_FRAGS) 1648 goto failure; 1649 1650 gfp_mask = sk->sk_allocation; 1651 if (gfp_mask & __GFP_WAIT) 1652 gfp_mask |= __GFP_REPEAT; 1653 1654 timeo = sock_sndtimeo(sk, noblock); 1655 while (1) { 1656 err = sock_error(sk); 1657 if (err != 0) 1658 goto failure; 1659 1660 err = -EPIPE; 1661 if (sk->sk_shutdown & SEND_SHUTDOWN) 1662 goto failure; 1663 1664 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1665 skb = alloc_skb(header_len, gfp_mask); 1666 if (skb) { 1667 int i; 1668 1669 /* No pages, we're done... */ 1670 if (!data_len) 1671 break; 1672 1673 skb->truesize += data_len; 1674 skb_shinfo(skb)->nr_frags = npages; 1675 for (i = 0; i < npages; i++) { 1676 struct page *page; 1677 1678 page = alloc_pages(sk->sk_allocation, 0); 1679 if (!page) { 1680 err = -ENOBUFS; 1681 skb_shinfo(skb)->nr_frags = i; 1682 kfree_skb(skb); 1683 goto failure; 1684 } 1685 1686 __skb_fill_page_desc(skb, i, 1687 page, 0, 1688 (data_len >= PAGE_SIZE ? 1689 PAGE_SIZE : 1690 data_len)); 1691 data_len -= PAGE_SIZE; 1692 } 1693 1694 /* Full success... */ 1695 break; 1696 } 1697 err = -ENOBUFS; 1698 goto failure; 1699 } 1700 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1701 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1702 err = -EAGAIN; 1703 if (!timeo) 1704 goto failure; 1705 if (signal_pending(current)) 1706 goto interrupted; 1707 timeo = sock_wait_for_wmem(sk, timeo); 1708 } 1709 1710 skb_set_owner_w(skb, sk); 1711 return skb; 1712 1713 interrupted: 1714 err = sock_intr_errno(timeo); 1715 failure: 1716 *errcode = err; 1717 return NULL; 1718 } 1719 EXPORT_SYMBOL(sock_alloc_send_pskb); 1720 1721 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1722 int noblock, int *errcode) 1723 { 1724 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode); 1725 } 1726 EXPORT_SYMBOL(sock_alloc_send_skb); 1727 1728 /* On 32bit arches, an skb frag is limited to 2^15 */ 1729 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1730 1731 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 1732 { 1733 int order; 1734 1735 if (pfrag->page) { 1736 if (atomic_read(&pfrag->page->_count) == 1) { 1737 pfrag->offset = 0; 1738 return true; 1739 } 1740 if (pfrag->offset < pfrag->size) 1741 return true; 1742 put_page(pfrag->page); 1743 } 1744 1745 /* We restrict high order allocations to users that can afford to wait */ 1746 order = (sk->sk_allocation & __GFP_WAIT) ? SKB_FRAG_PAGE_ORDER : 0; 1747 1748 do { 1749 gfp_t gfp = sk->sk_allocation; 1750 1751 if (order) 1752 gfp |= __GFP_COMP | __GFP_NOWARN; 1753 pfrag->page = alloc_pages(gfp, order); 1754 if (likely(pfrag->page)) { 1755 pfrag->offset = 0; 1756 pfrag->size = PAGE_SIZE << order; 1757 return true; 1758 } 1759 } while (--order >= 0); 1760 1761 sk_enter_memory_pressure(sk); 1762 sk_stream_moderate_sndbuf(sk); 1763 return false; 1764 } 1765 EXPORT_SYMBOL(sk_page_frag_refill); 1766 1767 static void __lock_sock(struct sock *sk) 1768 __releases(&sk->sk_lock.slock) 1769 __acquires(&sk->sk_lock.slock) 1770 { 1771 DEFINE_WAIT(wait); 1772 1773 for (;;) { 1774 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 1775 TASK_UNINTERRUPTIBLE); 1776 spin_unlock_bh(&sk->sk_lock.slock); 1777 schedule(); 1778 spin_lock_bh(&sk->sk_lock.slock); 1779 if (!sock_owned_by_user(sk)) 1780 break; 1781 } 1782 finish_wait(&sk->sk_lock.wq, &wait); 1783 } 1784 1785 static void __release_sock(struct sock *sk) 1786 __releases(&sk->sk_lock.slock) 1787 __acquires(&sk->sk_lock.slock) 1788 { 1789 struct sk_buff *skb = sk->sk_backlog.head; 1790 1791 do { 1792 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 1793 bh_unlock_sock(sk); 1794 1795 do { 1796 struct sk_buff *next = skb->next; 1797 1798 prefetch(next); 1799 WARN_ON_ONCE(skb_dst_is_noref(skb)); 1800 skb->next = NULL; 1801 sk_backlog_rcv(sk, skb); 1802 1803 /* 1804 * We are in process context here with softirqs 1805 * disabled, use cond_resched_softirq() to preempt. 1806 * This is safe to do because we've taken the backlog 1807 * queue private: 1808 */ 1809 cond_resched_softirq(); 1810 1811 skb = next; 1812 } while (skb != NULL); 1813 1814 bh_lock_sock(sk); 1815 } while ((skb = sk->sk_backlog.head) != NULL); 1816 1817 /* 1818 * Doing the zeroing here guarantee we can not loop forever 1819 * while a wild producer attempts to flood us. 1820 */ 1821 sk->sk_backlog.len = 0; 1822 } 1823 1824 /** 1825 * sk_wait_data - wait for data to arrive at sk_receive_queue 1826 * @sk: sock to wait on 1827 * @timeo: for how long 1828 * 1829 * Now socket state including sk->sk_err is changed only under lock, 1830 * hence we may omit checks after joining wait queue. 1831 * We check receive queue before schedule() only as optimization; 1832 * it is very likely that release_sock() added new data. 1833 */ 1834 int sk_wait_data(struct sock *sk, long *timeo) 1835 { 1836 int rc; 1837 DEFINE_WAIT(wait); 1838 1839 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1840 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1841 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); 1842 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1843 finish_wait(sk_sleep(sk), &wait); 1844 return rc; 1845 } 1846 EXPORT_SYMBOL(sk_wait_data); 1847 1848 /** 1849 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 1850 * @sk: socket 1851 * @size: memory size to allocate 1852 * @kind: allocation type 1853 * 1854 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 1855 * rmem allocation. This function assumes that protocols which have 1856 * memory_pressure use sk_wmem_queued as write buffer accounting. 1857 */ 1858 int __sk_mem_schedule(struct sock *sk, int size, int kind) 1859 { 1860 struct proto *prot = sk->sk_prot; 1861 int amt = sk_mem_pages(size); 1862 long allocated; 1863 int parent_status = UNDER_LIMIT; 1864 1865 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; 1866 1867 allocated = sk_memory_allocated_add(sk, amt, &parent_status); 1868 1869 /* Under limit. */ 1870 if (parent_status == UNDER_LIMIT && 1871 allocated <= sk_prot_mem_limits(sk, 0)) { 1872 sk_leave_memory_pressure(sk); 1873 return 1; 1874 } 1875 1876 /* Under pressure. (we or our parents) */ 1877 if ((parent_status > SOFT_LIMIT) || 1878 allocated > sk_prot_mem_limits(sk, 1)) 1879 sk_enter_memory_pressure(sk); 1880 1881 /* Over hard limit (we or our parents) */ 1882 if ((parent_status == OVER_LIMIT) || 1883 (allocated > sk_prot_mem_limits(sk, 2))) 1884 goto suppress_allocation; 1885 1886 /* guarantee minimum buffer size under pressure */ 1887 if (kind == SK_MEM_RECV) { 1888 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 1889 return 1; 1890 1891 } else { /* SK_MEM_SEND */ 1892 if (sk->sk_type == SOCK_STREAM) { 1893 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 1894 return 1; 1895 } else if (atomic_read(&sk->sk_wmem_alloc) < 1896 prot->sysctl_wmem[0]) 1897 return 1; 1898 } 1899 1900 if (sk_has_memory_pressure(sk)) { 1901 int alloc; 1902 1903 if (!sk_under_memory_pressure(sk)) 1904 return 1; 1905 alloc = sk_sockets_allocated_read_positive(sk); 1906 if (sk_prot_mem_limits(sk, 2) > alloc * 1907 sk_mem_pages(sk->sk_wmem_queued + 1908 atomic_read(&sk->sk_rmem_alloc) + 1909 sk->sk_forward_alloc)) 1910 return 1; 1911 } 1912 1913 suppress_allocation: 1914 1915 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 1916 sk_stream_moderate_sndbuf(sk); 1917 1918 /* Fail only if socket is _under_ its sndbuf. 1919 * In this case we cannot block, so that we have to fail. 1920 */ 1921 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 1922 return 1; 1923 } 1924 1925 trace_sock_exceed_buf_limit(sk, prot, allocated); 1926 1927 /* Alas. Undo changes. */ 1928 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM; 1929 1930 sk_memory_allocated_sub(sk, amt); 1931 1932 return 0; 1933 } 1934 EXPORT_SYMBOL(__sk_mem_schedule); 1935 1936 /** 1937 * __sk_reclaim - reclaim memory_allocated 1938 * @sk: socket 1939 */ 1940 void __sk_mem_reclaim(struct sock *sk) 1941 { 1942 sk_memory_allocated_sub(sk, 1943 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT); 1944 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1; 1945 1946 if (sk_under_memory_pressure(sk) && 1947 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 1948 sk_leave_memory_pressure(sk); 1949 } 1950 EXPORT_SYMBOL(__sk_mem_reclaim); 1951 1952 1953 /* 1954 * Set of default routines for initialising struct proto_ops when 1955 * the protocol does not support a particular function. In certain 1956 * cases where it makes no sense for a protocol to have a "do nothing" 1957 * function, some default processing is provided. 1958 */ 1959 1960 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 1961 { 1962 return -EOPNOTSUPP; 1963 } 1964 EXPORT_SYMBOL(sock_no_bind); 1965 1966 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 1967 int len, int flags) 1968 { 1969 return -EOPNOTSUPP; 1970 } 1971 EXPORT_SYMBOL(sock_no_connect); 1972 1973 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 1974 { 1975 return -EOPNOTSUPP; 1976 } 1977 EXPORT_SYMBOL(sock_no_socketpair); 1978 1979 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 1980 { 1981 return -EOPNOTSUPP; 1982 } 1983 EXPORT_SYMBOL(sock_no_accept); 1984 1985 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 1986 int *len, int peer) 1987 { 1988 return -EOPNOTSUPP; 1989 } 1990 EXPORT_SYMBOL(sock_no_getname); 1991 1992 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 1993 { 1994 return 0; 1995 } 1996 EXPORT_SYMBOL(sock_no_poll); 1997 1998 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 1999 { 2000 return -EOPNOTSUPP; 2001 } 2002 EXPORT_SYMBOL(sock_no_ioctl); 2003 2004 int sock_no_listen(struct socket *sock, int backlog) 2005 { 2006 return -EOPNOTSUPP; 2007 } 2008 EXPORT_SYMBOL(sock_no_listen); 2009 2010 int sock_no_shutdown(struct socket *sock, int how) 2011 { 2012 return -EOPNOTSUPP; 2013 } 2014 EXPORT_SYMBOL(sock_no_shutdown); 2015 2016 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2017 char __user *optval, unsigned int optlen) 2018 { 2019 return -EOPNOTSUPP; 2020 } 2021 EXPORT_SYMBOL(sock_no_setsockopt); 2022 2023 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2024 char __user *optval, int __user *optlen) 2025 { 2026 return -EOPNOTSUPP; 2027 } 2028 EXPORT_SYMBOL(sock_no_getsockopt); 2029 2030 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2031 size_t len) 2032 { 2033 return -EOPNOTSUPP; 2034 } 2035 EXPORT_SYMBOL(sock_no_sendmsg); 2036 2037 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2038 size_t len, int flags) 2039 { 2040 return -EOPNOTSUPP; 2041 } 2042 EXPORT_SYMBOL(sock_no_recvmsg); 2043 2044 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2045 { 2046 /* Mirror missing mmap method error code */ 2047 return -ENODEV; 2048 } 2049 EXPORT_SYMBOL(sock_no_mmap); 2050 2051 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2052 { 2053 ssize_t res; 2054 struct msghdr msg = {.msg_flags = flags}; 2055 struct kvec iov; 2056 char *kaddr = kmap(page); 2057 iov.iov_base = kaddr + offset; 2058 iov.iov_len = size; 2059 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2060 kunmap(page); 2061 return res; 2062 } 2063 EXPORT_SYMBOL(sock_no_sendpage); 2064 2065 /* 2066 * Default Socket Callbacks 2067 */ 2068 2069 static void sock_def_wakeup(struct sock *sk) 2070 { 2071 struct socket_wq *wq; 2072 2073 rcu_read_lock(); 2074 wq = rcu_dereference(sk->sk_wq); 2075 if (wq_has_sleeper(wq)) 2076 wake_up_interruptible_all(&wq->wait); 2077 rcu_read_unlock(); 2078 } 2079 2080 static void sock_def_error_report(struct sock *sk) 2081 { 2082 struct socket_wq *wq; 2083 2084 rcu_read_lock(); 2085 wq = rcu_dereference(sk->sk_wq); 2086 if (wq_has_sleeper(wq)) 2087 wake_up_interruptible_poll(&wq->wait, POLLERR); 2088 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2089 rcu_read_unlock(); 2090 } 2091 2092 static void sock_def_readable(struct sock *sk, int len) 2093 { 2094 struct socket_wq *wq; 2095 2096 rcu_read_lock(); 2097 wq = rcu_dereference(sk->sk_wq); 2098 if (wq_has_sleeper(wq)) 2099 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI | 2100 POLLRDNORM | POLLRDBAND); 2101 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2102 rcu_read_unlock(); 2103 } 2104 2105 static void sock_def_write_space(struct sock *sk) 2106 { 2107 struct socket_wq *wq; 2108 2109 rcu_read_lock(); 2110 2111 /* Do not wake up a writer until he can make "significant" 2112 * progress. --DaveM 2113 */ 2114 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2115 wq = rcu_dereference(sk->sk_wq); 2116 if (wq_has_sleeper(wq)) 2117 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 2118 POLLWRNORM | POLLWRBAND); 2119 2120 /* Should agree with poll, otherwise some programs break */ 2121 if (sock_writeable(sk)) 2122 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2123 } 2124 2125 rcu_read_unlock(); 2126 } 2127 2128 static void sock_def_destruct(struct sock *sk) 2129 { 2130 kfree(sk->sk_protinfo); 2131 } 2132 2133 void sk_send_sigurg(struct sock *sk) 2134 { 2135 if (sk->sk_socket && sk->sk_socket->file) 2136 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2137 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2138 } 2139 EXPORT_SYMBOL(sk_send_sigurg); 2140 2141 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2142 unsigned long expires) 2143 { 2144 if (!mod_timer(timer, expires)) 2145 sock_hold(sk); 2146 } 2147 EXPORT_SYMBOL(sk_reset_timer); 2148 2149 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2150 { 2151 if (timer_pending(timer) && del_timer(timer)) 2152 __sock_put(sk); 2153 } 2154 EXPORT_SYMBOL(sk_stop_timer); 2155 2156 void sock_init_data(struct socket *sock, struct sock *sk) 2157 { 2158 skb_queue_head_init(&sk->sk_receive_queue); 2159 skb_queue_head_init(&sk->sk_write_queue); 2160 skb_queue_head_init(&sk->sk_error_queue); 2161 #ifdef CONFIG_NET_DMA 2162 skb_queue_head_init(&sk->sk_async_wait_queue); 2163 #endif 2164 2165 sk->sk_send_head = NULL; 2166 2167 init_timer(&sk->sk_timer); 2168 2169 sk->sk_allocation = GFP_KERNEL; 2170 sk->sk_rcvbuf = sysctl_rmem_default; 2171 sk->sk_sndbuf = sysctl_wmem_default; 2172 sk->sk_state = TCP_CLOSE; 2173 sk_set_socket(sk, sock); 2174 2175 sock_set_flag(sk, SOCK_ZAPPED); 2176 2177 if (sock) { 2178 sk->sk_type = sock->type; 2179 sk->sk_wq = sock->wq; 2180 sock->sk = sk; 2181 } else 2182 sk->sk_wq = NULL; 2183 2184 spin_lock_init(&sk->sk_dst_lock); 2185 rwlock_init(&sk->sk_callback_lock); 2186 lockdep_set_class_and_name(&sk->sk_callback_lock, 2187 af_callback_keys + sk->sk_family, 2188 af_family_clock_key_strings[sk->sk_family]); 2189 2190 sk->sk_state_change = sock_def_wakeup; 2191 sk->sk_data_ready = sock_def_readable; 2192 sk->sk_write_space = sock_def_write_space; 2193 sk->sk_error_report = sock_def_error_report; 2194 sk->sk_destruct = sock_def_destruct; 2195 2196 sk->sk_frag.page = NULL; 2197 sk->sk_frag.offset = 0; 2198 sk->sk_peek_off = -1; 2199 2200 sk->sk_peer_pid = NULL; 2201 sk->sk_peer_cred = NULL; 2202 sk->sk_write_pending = 0; 2203 sk->sk_rcvlowat = 1; 2204 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2205 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2206 2207 sk->sk_stamp = ktime_set(-1L, 0); 2208 2209 /* 2210 * Before updating sk_refcnt, we must commit prior changes to memory 2211 * (Documentation/RCU/rculist_nulls.txt for details) 2212 */ 2213 smp_wmb(); 2214 atomic_set(&sk->sk_refcnt, 1); 2215 atomic_set(&sk->sk_drops, 0); 2216 } 2217 EXPORT_SYMBOL(sock_init_data); 2218 2219 void lock_sock_nested(struct sock *sk, int subclass) 2220 { 2221 might_sleep(); 2222 spin_lock_bh(&sk->sk_lock.slock); 2223 if (sk->sk_lock.owned) 2224 __lock_sock(sk); 2225 sk->sk_lock.owned = 1; 2226 spin_unlock(&sk->sk_lock.slock); 2227 /* 2228 * The sk_lock has mutex_lock() semantics here: 2229 */ 2230 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2231 local_bh_enable(); 2232 } 2233 EXPORT_SYMBOL(lock_sock_nested); 2234 2235 void release_sock(struct sock *sk) 2236 { 2237 /* 2238 * The sk_lock has mutex_unlock() semantics: 2239 */ 2240 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 2241 2242 spin_lock_bh(&sk->sk_lock.slock); 2243 if (sk->sk_backlog.tail) 2244 __release_sock(sk); 2245 2246 if (sk->sk_prot->release_cb) 2247 sk->sk_prot->release_cb(sk); 2248 2249 sk->sk_lock.owned = 0; 2250 if (waitqueue_active(&sk->sk_lock.wq)) 2251 wake_up(&sk->sk_lock.wq); 2252 spin_unlock_bh(&sk->sk_lock.slock); 2253 } 2254 EXPORT_SYMBOL(release_sock); 2255 2256 /** 2257 * lock_sock_fast - fast version of lock_sock 2258 * @sk: socket 2259 * 2260 * This version should be used for very small section, where process wont block 2261 * return false if fast path is taken 2262 * sk_lock.slock locked, owned = 0, BH disabled 2263 * return true if slow path is taken 2264 * sk_lock.slock unlocked, owned = 1, BH enabled 2265 */ 2266 bool lock_sock_fast(struct sock *sk) 2267 { 2268 might_sleep(); 2269 spin_lock_bh(&sk->sk_lock.slock); 2270 2271 if (!sk->sk_lock.owned) 2272 /* 2273 * Note : We must disable BH 2274 */ 2275 return false; 2276 2277 __lock_sock(sk); 2278 sk->sk_lock.owned = 1; 2279 spin_unlock(&sk->sk_lock.slock); 2280 /* 2281 * The sk_lock has mutex_lock() semantics here: 2282 */ 2283 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2284 local_bh_enable(); 2285 return true; 2286 } 2287 EXPORT_SYMBOL(lock_sock_fast); 2288 2289 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2290 { 2291 struct timeval tv; 2292 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2293 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2294 tv = ktime_to_timeval(sk->sk_stamp); 2295 if (tv.tv_sec == -1) 2296 return -ENOENT; 2297 if (tv.tv_sec == 0) { 2298 sk->sk_stamp = ktime_get_real(); 2299 tv = ktime_to_timeval(sk->sk_stamp); 2300 } 2301 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2302 } 2303 EXPORT_SYMBOL(sock_get_timestamp); 2304 2305 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2306 { 2307 struct timespec ts; 2308 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2309 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2310 ts = ktime_to_timespec(sk->sk_stamp); 2311 if (ts.tv_sec == -1) 2312 return -ENOENT; 2313 if (ts.tv_sec == 0) { 2314 sk->sk_stamp = ktime_get_real(); 2315 ts = ktime_to_timespec(sk->sk_stamp); 2316 } 2317 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2318 } 2319 EXPORT_SYMBOL(sock_get_timestampns); 2320 2321 void sock_enable_timestamp(struct sock *sk, int flag) 2322 { 2323 if (!sock_flag(sk, flag)) { 2324 unsigned long previous_flags = sk->sk_flags; 2325 2326 sock_set_flag(sk, flag); 2327 /* 2328 * we just set one of the two flags which require net 2329 * time stamping, but time stamping might have been on 2330 * already because of the other one 2331 */ 2332 if (!(previous_flags & SK_FLAGS_TIMESTAMP)) 2333 net_enable_timestamp(); 2334 } 2335 } 2336 2337 /* 2338 * Get a socket option on an socket. 2339 * 2340 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2341 * asynchronous errors should be reported by getsockopt. We assume 2342 * this means if you specify SO_ERROR (otherwise whats the point of it). 2343 */ 2344 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2345 char __user *optval, int __user *optlen) 2346 { 2347 struct sock *sk = sock->sk; 2348 2349 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2350 } 2351 EXPORT_SYMBOL(sock_common_getsockopt); 2352 2353 #ifdef CONFIG_COMPAT 2354 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2355 char __user *optval, int __user *optlen) 2356 { 2357 struct sock *sk = sock->sk; 2358 2359 if (sk->sk_prot->compat_getsockopt != NULL) 2360 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2361 optval, optlen); 2362 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2363 } 2364 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2365 #endif 2366 2367 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, 2368 struct msghdr *msg, size_t size, int flags) 2369 { 2370 struct sock *sk = sock->sk; 2371 int addr_len = 0; 2372 int err; 2373 2374 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT, 2375 flags & ~MSG_DONTWAIT, &addr_len); 2376 if (err >= 0) 2377 msg->msg_namelen = addr_len; 2378 return err; 2379 } 2380 EXPORT_SYMBOL(sock_common_recvmsg); 2381 2382 /* 2383 * Set socket options on an inet socket. 2384 */ 2385 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2386 char __user *optval, unsigned int optlen) 2387 { 2388 struct sock *sk = sock->sk; 2389 2390 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2391 } 2392 EXPORT_SYMBOL(sock_common_setsockopt); 2393 2394 #ifdef CONFIG_COMPAT 2395 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2396 char __user *optval, unsigned int optlen) 2397 { 2398 struct sock *sk = sock->sk; 2399 2400 if (sk->sk_prot->compat_setsockopt != NULL) 2401 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2402 optval, optlen); 2403 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2404 } 2405 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2406 #endif 2407 2408 void sk_common_release(struct sock *sk) 2409 { 2410 if (sk->sk_prot->destroy) 2411 sk->sk_prot->destroy(sk); 2412 2413 /* 2414 * Observation: when sock_common_release is called, processes have 2415 * no access to socket. But net still has. 2416 * Step one, detach it from networking: 2417 * 2418 * A. Remove from hash tables. 2419 */ 2420 2421 sk->sk_prot->unhash(sk); 2422 2423 /* 2424 * In this point socket cannot receive new packets, but it is possible 2425 * that some packets are in flight because some CPU runs receiver and 2426 * did hash table lookup before we unhashed socket. They will achieve 2427 * receive queue and will be purged by socket destructor. 2428 * 2429 * Also we still have packets pending on receive queue and probably, 2430 * our own packets waiting in device queues. sock_destroy will drain 2431 * receive queue, but transmitted packets will delay socket destruction 2432 * until the last reference will be released. 2433 */ 2434 2435 sock_orphan(sk); 2436 2437 xfrm_sk_free_policy(sk); 2438 2439 sk_refcnt_debug_release(sk); 2440 2441 if (sk->sk_frag.page) { 2442 put_page(sk->sk_frag.page); 2443 sk->sk_frag.page = NULL; 2444 } 2445 2446 sock_put(sk); 2447 } 2448 EXPORT_SYMBOL(sk_common_release); 2449 2450 #ifdef CONFIG_PROC_FS 2451 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2452 struct prot_inuse { 2453 int val[PROTO_INUSE_NR]; 2454 }; 2455 2456 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2457 2458 #ifdef CONFIG_NET_NS 2459 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2460 { 2461 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2462 } 2463 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2464 2465 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2466 { 2467 int cpu, idx = prot->inuse_idx; 2468 int res = 0; 2469 2470 for_each_possible_cpu(cpu) 2471 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2472 2473 return res >= 0 ? res : 0; 2474 } 2475 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2476 2477 static int __net_init sock_inuse_init_net(struct net *net) 2478 { 2479 net->core.inuse = alloc_percpu(struct prot_inuse); 2480 return net->core.inuse ? 0 : -ENOMEM; 2481 } 2482 2483 static void __net_exit sock_inuse_exit_net(struct net *net) 2484 { 2485 free_percpu(net->core.inuse); 2486 } 2487 2488 static struct pernet_operations net_inuse_ops = { 2489 .init = sock_inuse_init_net, 2490 .exit = sock_inuse_exit_net, 2491 }; 2492 2493 static __init int net_inuse_init(void) 2494 { 2495 if (register_pernet_subsys(&net_inuse_ops)) 2496 panic("Cannot initialize net inuse counters"); 2497 2498 return 0; 2499 } 2500 2501 core_initcall(net_inuse_init); 2502 #else 2503 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2504 2505 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2506 { 2507 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2508 } 2509 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2510 2511 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2512 { 2513 int cpu, idx = prot->inuse_idx; 2514 int res = 0; 2515 2516 for_each_possible_cpu(cpu) 2517 res += per_cpu(prot_inuse, cpu).val[idx]; 2518 2519 return res >= 0 ? res : 0; 2520 } 2521 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2522 #endif 2523 2524 static void assign_proto_idx(struct proto *prot) 2525 { 2526 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2527 2528 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2529 pr_err("PROTO_INUSE_NR exhausted\n"); 2530 return; 2531 } 2532 2533 set_bit(prot->inuse_idx, proto_inuse_idx); 2534 } 2535 2536 static void release_proto_idx(struct proto *prot) 2537 { 2538 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2539 clear_bit(prot->inuse_idx, proto_inuse_idx); 2540 } 2541 #else 2542 static inline void assign_proto_idx(struct proto *prot) 2543 { 2544 } 2545 2546 static inline void release_proto_idx(struct proto *prot) 2547 { 2548 } 2549 #endif 2550 2551 int proto_register(struct proto *prot, int alloc_slab) 2552 { 2553 if (alloc_slab) { 2554 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2555 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2556 NULL); 2557 2558 if (prot->slab == NULL) { 2559 pr_crit("%s: Can't create sock SLAB cache!\n", 2560 prot->name); 2561 goto out; 2562 } 2563 2564 if (prot->rsk_prot != NULL) { 2565 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name); 2566 if (prot->rsk_prot->slab_name == NULL) 2567 goto out_free_sock_slab; 2568 2569 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name, 2570 prot->rsk_prot->obj_size, 0, 2571 SLAB_HWCACHE_ALIGN, NULL); 2572 2573 if (prot->rsk_prot->slab == NULL) { 2574 pr_crit("%s: Can't create request sock SLAB cache!\n", 2575 prot->name); 2576 goto out_free_request_sock_slab_name; 2577 } 2578 } 2579 2580 if (prot->twsk_prot != NULL) { 2581 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2582 2583 if (prot->twsk_prot->twsk_slab_name == NULL) 2584 goto out_free_request_sock_slab; 2585 2586 prot->twsk_prot->twsk_slab = 2587 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2588 prot->twsk_prot->twsk_obj_size, 2589 0, 2590 SLAB_HWCACHE_ALIGN | 2591 prot->slab_flags, 2592 NULL); 2593 if (prot->twsk_prot->twsk_slab == NULL) 2594 goto out_free_timewait_sock_slab_name; 2595 } 2596 } 2597 2598 mutex_lock(&proto_list_mutex); 2599 list_add(&prot->node, &proto_list); 2600 assign_proto_idx(prot); 2601 mutex_unlock(&proto_list_mutex); 2602 return 0; 2603 2604 out_free_timewait_sock_slab_name: 2605 kfree(prot->twsk_prot->twsk_slab_name); 2606 out_free_request_sock_slab: 2607 if (prot->rsk_prot && prot->rsk_prot->slab) { 2608 kmem_cache_destroy(prot->rsk_prot->slab); 2609 prot->rsk_prot->slab = NULL; 2610 } 2611 out_free_request_sock_slab_name: 2612 if (prot->rsk_prot) 2613 kfree(prot->rsk_prot->slab_name); 2614 out_free_sock_slab: 2615 kmem_cache_destroy(prot->slab); 2616 prot->slab = NULL; 2617 out: 2618 return -ENOBUFS; 2619 } 2620 EXPORT_SYMBOL(proto_register); 2621 2622 void proto_unregister(struct proto *prot) 2623 { 2624 mutex_lock(&proto_list_mutex); 2625 release_proto_idx(prot); 2626 list_del(&prot->node); 2627 mutex_unlock(&proto_list_mutex); 2628 2629 if (prot->slab != NULL) { 2630 kmem_cache_destroy(prot->slab); 2631 prot->slab = NULL; 2632 } 2633 2634 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) { 2635 kmem_cache_destroy(prot->rsk_prot->slab); 2636 kfree(prot->rsk_prot->slab_name); 2637 prot->rsk_prot->slab = NULL; 2638 } 2639 2640 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2641 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2642 kfree(prot->twsk_prot->twsk_slab_name); 2643 prot->twsk_prot->twsk_slab = NULL; 2644 } 2645 } 2646 EXPORT_SYMBOL(proto_unregister); 2647 2648 #ifdef CONFIG_PROC_FS 2649 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2650 __acquires(proto_list_mutex) 2651 { 2652 mutex_lock(&proto_list_mutex); 2653 return seq_list_start_head(&proto_list, *pos); 2654 } 2655 2656 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2657 { 2658 return seq_list_next(v, &proto_list, pos); 2659 } 2660 2661 static void proto_seq_stop(struct seq_file *seq, void *v) 2662 __releases(proto_list_mutex) 2663 { 2664 mutex_unlock(&proto_list_mutex); 2665 } 2666 2667 static char proto_method_implemented(const void *method) 2668 { 2669 return method == NULL ? 'n' : 'y'; 2670 } 2671 static long sock_prot_memory_allocated(struct proto *proto) 2672 { 2673 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 2674 } 2675 2676 static char *sock_prot_memory_pressure(struct proto *proto) 2677 { 2678 return proto->memory_pressure != NULL ? 2679 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 2680 } 2681 2682 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 2683 { 2684 2685 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 2686 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 2687 proto->name, 2688 proto->obj_size, 2689 sock_prot_inuse_get(seq_file_net(seq), proto), 2690 sock_prot_memory_allocated(proto), 2691 sock_prot_memory_pressure(proto), 2692 proto->max_header, 2693 proto->slab == NULL ? "no" : "yes", 2694 module_name(proto->owner), 2695 proto_method_implemented(proto->close), 2696 proto_method_implemented(proto->connect), 2697 proto_method_implemented(proto->disconnect), 2698 proto_method_implemented(proto->accept), 2699 proto_method_implemented(proto->ioctl), 2700 proto_method_implemented(proto->init), 2701 proto_method_implemented(proto->destroy), 2702 proto_method_implemented(proto->shutdown), 2703 proto_method_implemented(proto->setsockopt), 2704 proto_method_implemented(proto->getsockopt), 2705 proto_method_implemented(proto->sendmsg), 2706 proto_method_implemented(proto->recvmsg), 2707 proto_method_implemented(proto->sendpage), 2708 proto_method_implemented(proto->bind), 2709 proto_method_implemented(proto->backlog_rcv), 2710 proto_method_implemented(proto->hash), 2711 proto_method_implemented(proto->unhash), 2712 proto_method_implemented(proto->get_port), 2713 proto_method_implemented(proto->enter_memory_pressure)); 2714 } 2715 2716 static int proto_seq_show(struct seq_file *seq, void *v) 2717 { 2718 if (v == &proto_list) 2719 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 2720 "protocol", 2721 "size", 2722 "sockets", 2723 "memory", 2724 "press", 2725 "maxhdr", 2726 "slab", 2727 "module", 2728 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 2729 else 2730 proto_seq_printf(seq, list_entry(v, struct proto, node)); 2731 return 0; 2732 } 2733 2734 static const struct seq_operations proto_seq_ops = { 2735 .start = proto_seq_start, 2736 .next = proto_seq_next, 2737 .stop = proto_seq_stop, 2738 .show = proto_seq_show, 2739 }; 2740 2741 static int proto_seq_open(struct inode *inode, struct file *file) 2742 { 2743 return seq_open_net(inode, file, &proto_seq_ops, 2744 sizeof(struct seq_net_private)); 2745 } 2746 2747 static const struct file_operations proto_seq_fops = { 2748 .owner = THIS_MODULE, 2749 .open = proto_seq_open, 2750 .read = seq_read, 2751 .llseek = seq_lseek, 2752 .release = seq_release_net, 2753 }; 2754 2755 static __net_init int proto_init_net(struct net *net) 2756 { 2757 if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops)) 2758 return -ENOMEM; 2759 2760 return 0; 2761 } 2762 2763 static __net_exit void proto_exit_net(struct net *net) 2764 { 2765 proc_net_remove(net, "protocols"); 2766 } 2767 2768 2769 static __net_initdata struct pernet_operations proto_net_ops = { 2770 .init = proto_init_net, 2771 .exit = proto_exit_net, 2772 }; 2773 2774 static int __init proto_init(void) 2775 { 2776 return register_pernet_subsys(&proto_net_ops); 2777 } 2778 2779 subsys_initcall(proto_init); 2780 2781 #endif /* PROC_FS */ 2782