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 #if defined(CONFIG_MEMCG_KMEM) 190 struct static_key memcg_socket_limit_enabled; 191 EXPORT_SYMBOL(memcg_socket_limit_enabled); 192 #endif 193 194 /* 195 * Make lock validator output more readable. (we pre-construct these 196 * strings build-time, so that runtime initialization of socket 197 * locks is fast): 198 */ 199 static const char *const af_family_key_strings[AF_MAX+1] = { 200 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" , 201 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK", 202 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" , 203 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" , 204 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" , 205 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" , 206 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" , 207 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" , 208 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" , 209 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" , 210 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" , 211 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" , 212 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" , 213 "sk_lock-AF_NFC" , "sk_lock-AF_MAX" 214 }; 215 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 216 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" , 217 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK", 218 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" , 219 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" , 220 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" , 221 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" , 222 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" , 223 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" , 224 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" , 225 "slock-27" , "slock-28" , "slock-AF_CAN" , 226 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" , 227 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" , 228 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" , 229 "slock-AF_NFC" , "slock-AF_MAX" 230 }; 231 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 232 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" , 233 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK", 234 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" , 235 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" , 236 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" , 237 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" , 238 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" , 239 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" , 240 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" , 241 "clock-27" , "clock-28" , "clock-AF_CAN" , 242 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" , 243 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" , 244 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" , 245 "clock-AF_NFC" , "clock-AF_MAX" 246 }; 247 248 /* 249 * sk_callback_lock locking rules are per-address-family, 250 * so split the lock classes by using a per-AF key: 251 */ 252 static struct lock_class_key af_callback_keys[AF_MAX]; 253 254 /* Take into consideration the size of the struct sk_buff overhead in the 255 * determination of these values, since that is non-constant across 256 * platforms. This makes socket queueing behavior and performance 257 * not depend upon such differences. 258 */ 259 #define _SK_MEM_PACKETS 256 260 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 261 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 262 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 263 264 /* Run time adjustable parameters. */ 265 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 266 EXPORT_SYMBOL(sysctl_wmem_max); 267 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 268 EXPORT_SYMBOL(sysctl_rmem_max); 269 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 270 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 271 272 /* Maximal space eaten by iovec or ancillary data plus some space */ 273 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); 274 EXPORT_SYMBOL(sysctl_optmem_max); 275 276 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE; 277 EXPORT_SYMBOL_GPL(memalloc_socks); 278 279 /** 280 * sk_set_memalloc - sets %SOCK_MEMALLOC 281 * @sk: socket to set it on 282 * 283 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 284 * It's the responsibility of the admin to adjust min_free_kbytes 285 * to meet the requirements 286 */ 287 void sk_set_memalloc(struct sock *sk) 288 { 289 sock_set_flag(sk, SOCK_MEMALLOC); 290 sk->sk_allocation |= __GFP_MEMALLOC; 291 static_key_slow_inc(&memalloc_socks); 292 } 293 EXPORT_SYMBOL_GPL(sk_set_memalloc); 294 295 void sk_clear_memalloc(struct sock *sk) 296 { 297 sock_reset_flag(sk, SOCK_MEMALLOC); 298 sk->sk_allocation &= ~__GFP_MEMALLOC; 299 static_key_slow_dec(&memalloc_socks); 300 301 /* 302 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 303 * progress of swapping. However, if SOCK_MEMALLOC is cleared while 304 * it has rmem allocations there is a risk that the user of the 305 * socket cannot make forward progress due to exceeding the rmem 306 * limits. By rights, sk_clear_memalloc() should only be called 307 * on sockets being torn down but warn and reset the accounting if 308 * that assumption breaks. 309 */ 310 if (WARN_ON(sk->sk_forward_alloc)) 311 sk_mem_reclaim(sk); 312 } 313 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 314 315 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 316 { 317 int ret; 318 unsigned long pflags = current->flags; 319 320 /* these should have been dropped before queueing */ 321 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 322 323 current->flags |= PF_MEMALLOC; 324 ret = sk->sk_backlog_rcv(sk, skb); 325 tsk_restore_flags(current, pflags, PF_MEMALLOC); 326 327 return ret; 328 } 329 EXPORT_SYMBOL(__sk_backlog_rcv); 330 331 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen) 332 { 333 struct timeval tv; 334 335 if (optlen < sizeof(tv)) 336 return -EINVAL; 337 if (copy_from_user(&tv, optval, sizeof(tv))) 338 return -EFAULT; 339 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 340 return -EDOM; 341 342 if (tv.tv_sec < 0) { 343 static int warned __read_mostly; 344 345 *timeo_p = 0; 346 if (warned < 10 && net_ratelimit()) { 347 warned++; 348 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 349 __func__, current->comm, task_pid_nr(current)); 350 } 351 return 0; 352 } 353 *timeo_p = MAX_SCHEDULE_TIMEOUT; 354 if (tv.tv_sec == 0 && tv.tv_usec == 0) 355 return 0; 356 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1)) 357 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ); 358 return 0; 359 } 360 361 static void sock_warn_obsolete_bsdism(const char *name) 362 { 363 static int warned; 364 static char warncomm[TASK_COMM_LEN]; 365 if (strcmp(warncomm, current->comm) && warned < 5) { 366 strcpy(warncomm, current->comm); 367 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", 368 warncomm, name); 369 warned++; 370 } 371 } 372 373 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 374 375 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 376 { 377 if (sk->sk_flags & flags) { 378 sk->sk_flags &= ~flags; 379 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 380 net_disable_timestamp(); 381 } 382 } 383 384 385 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 386 { 387 int err; 388 int skb_len; 389 unsigned long flags; 390 struct sk_buff_head *list = &sk->sk_receive_queue; 391 392 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 393 atomic_inc(&sk->sk_drops); 394 trace_sock_rcvqueue_full(sk, skb); 395 return -ENOMEM; 396 } 397 398 err = sk_filter(sk, skb); 399 if (err) 400 return err; 401 402 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 403 atomic_inc(&sk->sk_drops); 404 return -ENOBUFS; 405 } 406 407 skb->dev = NULL; 408 skb_set_owner_r(skb, sk); 409 410 /* Cache the SKB length before we tack it onto the receive 411 * queue. Once it is added it no longer belongs to us and 412 * may be freed by other threads of control pulling packets 413 * from the queue. 414 */ 415 skb_len = skb->len; 416 417 /* we escape from rcu protected region, make sure we dont leak 418 * a norefcounted dst 419 */ 420 skb_dst_force(skb); 421 422 spin_lock_irqsave(&list->lock, flags); 423 skb->dropcount = atomic_read(&sk->sk_drops); 424 __skb_queue_tail(list, skb); 425 spin_unlock_irqrestore(&list->lock, flags); 426 427 if (!sock_flag(sk, SOCK_DEAD)) 428 sk->sk_data_ready(sk, skb_len); 429 return 0; 430 } 431 EXPORT_SYMBOL(sock_queue_rcv_skb); 432 433 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested) 434 { 435 int rc = NET_RX_SUCCESS; 436 437 if (sk_filter(sk, skb)) 438 goto discard_and_relse; 439 440 skb->dev = NULL; 441 442 if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) { 443 atomic_inc(&sk->sk_drops); 444 goto discard_and_relse; 445 } 446 if (nested) 447 bh_lock_sock_nested(sk); 448 else 449 bh_lock_sock(sk); 450 if (!sock_owned_by_user(sk)) { 451 /* 452 * trylock + unlock semantics: 453 */ 454 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 455 456 rc = sk_backlog_rcv(sk, skb); 457 458 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 459 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 460 bh_unlock_sock(sk); 461 atomic_inc(&sk->sk_drops); 462 goto discard_and_relse; 463 } 464 465 bh_unlock_sock(sk); 466 out: 467 sock_put(sk); 468 return rc; 469 discard_and_relse: 470 kfree_skb(skb); 471 goto out; 472 } 473 EXPORT_SYMBOL(sk_receive_skb); 474 475 void sk_reset_txq(struct sock *sk) 476 { 477 sk_tx_queue_clear(sk); 478 } 479 EXPORT_SYMBOL(sk_reset_txq); 480 481 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 482 { 483 struct dst_entry *dst = __sk_dst_get(sk); 484 485 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 486 sk_tx_queue_clear(sk); 487 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 488 dst_release(dst); 489 return NULL; 490 } 491 492 return dst; 493 } 494 EXPORT_SYMBOL(__sk_dst_check); 495 496 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 497 { 498 struct dst_entry *dst = sk_dst_get(sk); 499 500 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 501 sk_dst_reset(sk); 502 dst_release(dst); 503 return NULL; 504 } 505 506 return dst; 507 } 508 EXPORT_SYMBOL(sk_dst_check); 509 510 static int sock_setbindtodevice(struct sock *sk, char __user *optval, 511 int optlen) 512 { 513 int ret = -ENOPROTOOPT; 514 #ifdef CONFIG_NETDEVICES 515 struct net *net = sock_net(sk); 516 char devname[IFNAMSIZ]; 517 int index; 518 519 /* Sorry... */ 520 ret = -EPERM; 521 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 522 goto out; 523 524 ret = -EINVAL; 525 if (optlen < 0) 526 goto out; 527 528 /* Bind this socket to a particular device like "eth0", 529 * as specified in the passed interface name. If the 530 * name is "" or the option length is zero the socket 531 * is not bound. 532 */ 533 if (optlen > IFNAMSIZ - 1) 534 optlen = IFNAMSIZ - 1; 535 memset(devname, 0, sizeof(devname)); 536 537 ret = -EFAULT; 538 if (copy_from_user(devname, optval, optlen)) 539 goto out; 540 541 index = 0; 542 if (devname[0] != '\0') { 543 struct net_device *dev; 544 545 rcu_read_lock(); 546 dev = dev_get_by_name_rcu(net, devname); 547 if (dev) 548 index = dev->ifindex; 549 rcu_read_unlock(); 550 ret = -ENODEV; 551 if (!dev) 552 goto out; 553 } 554 555 lock_sock(sk); 556 sk->sk_bound_dev_if = index; 557 sk_dst_reset(sk); 558 release_sock(sk); 559 560 ret = 0; 561 562 out: 563 #endif 564 565 return ret; 566 } 567 568 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 569 int __user *optlen, int len) 570 { 571 int ret = -ENOPROTOOPT; 572 #ifdef CONFIG_NETDEVICES 573 struct net *net = sock_net(sk); 574 struct net_device *dev; 575 char devname[IFNAMSIZ]; 576 unsigned seq; 577 578 if (sk->sk_bound_dev_if == 0) { 579 len = 0; 580 goto zero; 581 } 582 583 ret = -EINVAL; 584 if (len < IFNAMSIZ) 585 goto out; 586 587 retry: 588 seq = read_seqcount_begin(&devnet_rename_seq); 589 rcu_read_lock(); 590 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if); 591 ret = -ENODEV; 592 if (!dev) { 593 rcu_read_unlock(); 594 goto out; 595 } 596 597 strcpy(devname, dev->name); 598 rcu_read_unlock(); 599 if (read_seqcount_retry(&devnet_rename_seq, seq)) 600 goto retry; 601 602 len = strlen(devname) + 1; 603 604 ret = -EFAULT; 605 if (copy_to_user(optval, devname, len)) 606 goto out; 607 608 zero: 609 ret = -EFAULT; 610 if (put_user(len, optlen)) 611 goto out; 612 613 ret = 0; 614 615 out: 616 #endif 617 618 return ret; 619 } 620 621 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) 622 { 623 if (valbool) 624 sock_set_flag(sk, bit); 625 else 626 sock_reset_flag(sk, bit); 627 } 628 629 /* 630 * This is meant for all protocols to use and covers goings on 631 * at the socket level. Everything here is generic. 632 */ 633 634 int sock_setsockopt(struct socket *sock, int level, int optname, 635 char __user *optval, unsigned int optlen) 636 { 637 struct sock *sk = sock->sk; 638 int val; 639 int valbool; 640 struct linger ling; 641 int ret = 0; 642 643 /* 644 * Options without arguments 645 */ 646 647 if (optname == SO_BINDTODEVICE) 648 return sock_setbindtodevice(sk, optval, optlen); 649 650 if (optlen < sizeof(int)) 651 return -EINVAL; 652 653 if (get_user(val, (int __user *)optval)) 654 return -EFAULT; 655 656 valbool = val ? 1 : 0; 657 658 lock_sock(sk); 659 660 switch (optname) { 661 case SO_DEBUG: 662 if (val && !capable(CAP_NET_ADMIN)) 663 ret = -EACCES; 664 else 665 sock_valbool_flag(sk, SOCK_DBG, valbool); 666 break; 667 case SO_REUSEADDR: 668 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 669 break; 670 case SO_REUSEPORT: 671 sk->sk_reuseport = valbool; 672 break; 673 case SO_TYPE: 674 case SO_PROTOCOL: 675 case SO_DOMAIN: 676 case SO_ERROR: 677 ret = -ENOPROTOOPT; 678 break; 679 case SO_DONTROUTE: 680 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 681 break; 682 case SO_BROADCAST: 683 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 684 break; 685 case SO_SNDBUF: 686 /* Don't error on this BSD doesn't and if you think 687 * about it this is right. Otherwise apps have to 688 * play 'guess the biggest size' games. RCVBUF/SNDBUF 689 * are treated in BSD as hints 690 */ 691 val = min_t(u32, val, sysctl_wmem_max); 692 set_sndbuf: 693 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 694 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF); 695 /* Wake up sending tasks if we upped the value. */ 696 sk->sk_write_space(sk); 697 break; 698 699 case SO_SNDBUFFORCE: 700 if (!capable(CAP_NET_ADMIN)) { 701 ret = -EPERM; 702 break; 703 } 704 goto set_sndbuf; 705 706 case SO_RCVBUF: 707 /* Don't error on this BSD doesn't and if you think 708 * about it this is right. Otherwise apps have to 709 * play 'guess the biggest size' games. RCVBUF/SNDBUF 710 * are treated in BSD as hints 711 */ 712 val = min_t(u32, val, sysctl_rmem_max); 713 set_rcvbuf: 714 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 715 /* 716 * We double it on the way in to account for 717 * "struct sk_buff" etc. overhead. Applications 718 * assume that the SO_RCVBUF setting they make will 719 * allow that much actual data to be received on that 720 * socket. 721 * 722 * Applications are unaware that "struct sk_buff" and 723 * other overheads allocate from the receive buffer 724 * during socket buffer allocation. 725 * 726 * And after considering the possible alternatives, 727 * returning the value we actually used in getsockopt 728 * is the most desirable behavior. 729 */ 730 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF); 731 break; 732 733 case SO_RCVBUFFORCE: 734 if (!capable(CAP_NET_ADMIN)) { 735 ret = -EPERM; 736 break; 737 } 738 goto set_rcvbuf; 739 740 case SO_KEEPALIVE: 741 #ifdef CONFIG_INET 742 if (sk->sk_protocol == IPPROTO_TCP && 743 sk->sk_type == SOCK_STREAM) 744 tcp_set_keepalive(sk, valbool); 745 #endif 746 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 747 break; 748 749 case SO_OOBINLINE: 750 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 751 break; 752 753 case SO_NO_CHECK: 754 sk->sk_no_check = valbool; 755 break; 756 757 case SO_PRIORITY: 758 if ((val >= 0 && val <= 6) || 759 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 760 sk->sk_priority = val; 761 else 762 ret = -EPERM; 763 break; 764 765 case SO_LINGER: 766 if (optlen < sizeof(ling)) { 767 ret = -EINVAL; /* 1003.1g */ 768 break; 769 } 770 if (copy_from_user(&ling, optval, sizeof(ling))) { 771 ret = -EFAULT; 772 break; 773 } 774 if (!ling.l_onoff) 775 sock_reset_flag(sk, SOCK_LINGER); 776 else { 777 #if (BITS_PER_LONG == 32) 778 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 779 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 780 else 781 #endif 782 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 783 sock_set_flag(sk, SOCK_LINGER); 784 } 785 break; 786 787 case SO_BSDCOMPAT: 788 sock_warn_obsolete_bsdism("setsockopt"); 789 break; 790 791 case SO_PASSCRED: 792 if (valbool) 793 set_bit(SOCK_PASSCRED, &sock->flags); 794 else 795 clear_bit(SOCK_PASSCRED, &sock->flags); 796 break; 797 798 case SO_TIMESTAMP: 799 case SO_TIMESTAMPNS: 800 if (valbool) { 801 if (optname == SO_TIMESTAMP) 802 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 803 else 804 sock_set_flag(sk, SOCK_RCVTSTAMPNS); 805 sock_set_flag(sk, SOCK_RCVTSTAMP); 806 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 807 } else { 808 sock_reset_flag(sk, SOCK_RCVTSTAMP); 809 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 810 } 811 break; 812 813 case SO_TIMESTAMPING: 814 if (val & ~SOF_TIMESTAMPING_MASK) { 815 ret = -EINVAL; 816 break; 817 } 818 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE, 819 val & SOF_TIMESTAMPING_TX_HARDWARE); 820 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE, 821 val & SOF_TIMESTAMPING_TX_SOFTWARE); 822 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE, 823 val & SOF_TIMESTAMPING_RX_HARDWARE); 824 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 825 sock_enable_timestamp(sk, 826 SOCK_TIMESTAMPING_RX_SOFTWARE); 827 else 828 sock_disable_timestamp(sk, 829 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 830 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE, 831 val & SOF_TIMESTAMPING_SOFTWARE); 832 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE, 833 val & SOF_TIMESTAMPING_SYS_HARDWARE); 834 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE, 835 val & SOF_TIMESTAMPING_RAW_HARDWARE); 836 break; 837 838 case SO_RCVLOWAT: 839 if (val < 0) 840 val = INT_MAX; 841 sk->sk_rcvlowat = val ? : 1; 842 break; 843 844 case SO_RCVTIMEO: 845 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); 846 break; 847 848 case SO_SNDTIMEO: 849 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); 850 break; 851 852 case SO_ATTACH_FILTER: 853 ret = -EINVAL; 854 if (optlen == sizeof(struct sock_fprog)) { 855 struct sock_fprog fprog; 856 857 ret = -EFAULT; 858 if (copy_from_user(&fprog, optval, sizeof(fprog))) 859 break; 860 861 ret = sk_attach_filter(&fprog, sk); 862 } 863 break; 864 865 case SO_DETACH_FILTER: 866 ret = sk_detach_filter(sk); 867 break; 868 869 case SO_LOCK_FILTER: 870 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 871 ret = -EPERM; 872 else 873 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 874 break; 875 876 case SO_PASSSEC: 877 if (valbool) 878 set_bit(SOCK_PASSSEC, &sock->flags); 879 else 880 clear_bit(SOCK_PASSSEC, &sock->flags); 881 break; 882 case SO_MARK: 883 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 884 ret = -EPERM; 885 else 886 sk->sk_mark = val; 887 break; 888 889 /* We implement the SO_SNDLOWAT etc to 890 not be settable (1003.1g 5.3) */ 891 case SO_RXQ_OVFL: 892 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 893 break; 894 895 case SO_WIFI_STATUS: 896 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 897 break; 898 899 case SO_PEEK_OFF: 900 if (sock->ops->set_peek_off) 901 sock->ops->set_peek_off(sk, val); 902 else 903 ret = -EOPNOTSUPP; 904 break; 905 906 case SO_NOFCS: 907 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 908 break; 909 910 default: 911 ret = -ENOPROTOOPT; 912 break; 913 } 914 release_sock(sk); 915 return ret; 916 } 917 EXPORT_SYMBOL(sock_setsockopt); 918 919 920 void cred_to_ucred(struct pid *pid, const struct cred *cred, 921 struct ucred *ucred) 922 { 923 ucred->pid = pid_vnr(pid); 924 ucred->uid = ucred->gid = -1; 925 if (cred) { 926 struct user_namespace *current_ns = current_user_ns(); 927 928 ucred->uid = from_kuid_munged(current_ns, cred->euid); 929 ucred->gid = from_kgid_munged(current_ns, cred->egid); 930 } 931 } 932 EXPORT_SYMBOL_GPL(cred_to_ucred); 933 934 int sock_getsockopt(struct socket *sock, int level, int optname, 935 char __user *optval, int __user *optlen) 936 { 937 struct sock *sk = sock->sk; 938 939 union { 940 int val; 941 struct linger ling; 942 struct timeval tm; 943 } v; 944 945 int lv = sizeof(int); 946 int len; 947 948 if (get_user(len, optlen)) 949 return -EFAULT; 950 if (len < 0) 951 return -EINVAL; 952 953 memset(&v, 0, sizeof(v)); 954 955 switch (optname) { 956 case SO_DEBUG: 957 v.val = sock_flag(sk, SOCK_DBG); 958 break; 959 960 case SO_DONTROUTE: 961 v.val = sock_flag(sk, SOCK_LOCALROUTE); 962 break; 963 964 case SO_BROADCAST: 965 v.val = sock_flag(sk, SOCK_BROADCAST); 966 break; 967 968 case SO_SNDBUF: 969 v.val = sk->sk_sndbuf; 970 break; 971 972 case SO_RCVBUF: 973 v.val = sk->sk_rcvbuf; 974 break; 975 976 case SO_REUSEADDR: 977 v.val = sk->sk_reuse; 978 break; 979 980 case SO_REUSEPORT: 981 v.val = sk->sk_reuseport; 982 break; 983 984 case SO_KEEPALIVE: 985 v.val = sock_flag(sk, SOCK_KEEPOPEN); 986 break; 987 988 case SO_TYPE: 989 v.val = sk->sk_type; 990 break; 991 992 case SO_PROTOCOL: 993 v.val = sk->sk_protocol; 994 break; 995 996 case SO_DOMAIN: 997 v.val = sk->sk_family; 998 break; 999 1000 case SO_ERROR: 1001 v.val = -sock_error(sk); 1002 if (v.val == 0) 1003 v.val = xchg(&sk->sk_err_soft, 0); 1004 break; 1005 1006 case SO_OOBINLINE: 1007 v.val = sock_flag(sk, SOCK_URGINLINE); 1008 break; 1009 1010 case SO_NO_CHECK: 1011 v.val = sk->sk_no_check; 1012 break; 1013 1014 case SO_PRIORITY: 1015 v.val = sk->sk_priority; 1016 break; 1017 1018 case SO_LINGER: 1019 lv = sizeof(v.ling); 1020 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1021 v.ling.l_linger = sk->sk_lingertime / HZ; 1022 break; 1023 1024 case SO_BSDCOMPAT: 1025 sock_warn_obsolete_bsdism("getsockopt"); 1026 break; 1027 1028 case SO_TIMESTAMP: 1029 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1030 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1031 break; 1032 1033 case SO_TIMESTAMPNS: 1034 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 1035 break; 1036 1037 case SO_TIMESTAMPING: 1038 v.val = 0; 1039 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE)) 1040 v.val |= SOF_TIMESTAMPING_TX_HARDWARE; 1041 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE)) 1042 v.val |= SOF_TIMESTAMPING_TX_SOFTWARE; 1043 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE)) 1044 v.val |= SOF_TIMESTAMPING_RX_HARDWARE; 1045 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE)) 1046 v.val |= SOF_TIMESTAMPING_RX_SOFTWARE; 1047 if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) 1048 v.val |= SOF_TIMESTAMPING_SOFTWARE; 1049 if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)) 1050 v.val |= SOF_TIMESTAMPING_SYS_HARDWARE; 1051 if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) 1052 v.val |= SOF_TIMESTAMPING_RAW_HARDWARE; 1053 break; 1054 1055 case SO_RCVTIMEO: 1056 lv = sizeof(struct timeval); 1057 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 1058 v.tm.tv_sec = 0; 1059 v.tm.tv_usec = 0; 1060 } else { 1061 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 1062 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 1063 } 1064 break; 1065 1066 case SO_SNDTIMEO: 1067 lv = sizeof(struct timeval); 1068 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 1069 v.tm.tv_sec = 0; 1070 v.tm.tv_usec = 0; 1071 } else { 1072 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1073 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1074 } 1075 break; 1076 1077 case SO_RCVLOWAT: 1078 v.val = sk->sk_rcvlowat; 1079 break; 1080 1081 case SO_SNDLOWAT: 1082 v.val = 1; 1083 break; 1084 1085 case SO_PASSCRED: 1086 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1087 break; 1088 1089 case SO_PEERCRED: 1090 { 1091 struct ucred peercred; 1092 if (len > sizeof(peercred)) 1093 len = sizeof(peercred); 1094 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1095 if (copy_to_user(optval, &peercred, len)) 1096 return -EFAULT; 1097 goto lenout; 1098 } 1099 1100 case SO_PEERNAME: 1101 { 1102 char address[128]; 1103 1104 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1105 return -ENOTCONN; 1106 if (lv < len) 1107 return -EINVAL; 1108 if (copy_to_user(optval, address, len)) 1109 return -EFAULT; 1110 goto lenout; 1111 } 1112 1113 /* Dubious BSD thing... Probably nobody even uses it, but 1114 * the UNIX standard wants it for whatever reason... -DaveM 1115 */ 1116 case SO_ACCEPTCONN: 1117 v.val = sk->sk_state == TCP_LISTEN; 1118 break; 1119 1120 case SO_PASSSEC: 1121 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1122 break; 1123 1124 case SO_PEERSEC: 1125 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1126 1127 case SO_MARK: 1128 v.val = sk->sk_mark; 1129 break; 1130 1131 case SO_RXQ_OVFL: 1132 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1133 break; 1134 1135 case SO_WIFI_STATUS: 1136 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1137 break; 1138 1139 case SO_PEEK_OFF: 1140 if (!sock->ops->set_peek_off) 1141 return -EOPNOTSUPP; 1142 1143 v.val = sk->sk_peek_off; 1144 break; 1145 case SO_NOFCS: 1146 v.val = sock_flag(sk, SOCK_NOFCS); 1147 break; 1148 1149 case SO_BINDTODEVICE: 1150 return sock_getbindtodevice(sk, optval, optlen, len); 1151 1152 case SO_GET_FILTER: 1153 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1154 if (len < 0) 1155 return len; 1156 1157 goto lenout; 1158 1159 case SO_LOCK_FILTER: 1160 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1161 break; 1162 1163 default: 1164 return -ENOPROTOOPT; 1165 } 1166 1167 if (len > lv) 1168 len = lv; 1169 if (copy_to_user(optval, &v, len)) 1170 return -EFAULT; 1171 lenout: 1172 if (put_user(len, optlen)) 1173 return -EFAULT; 1174 return 0; 1175 } 1176 1177 /* 1178 * Initialize an sk_lock. 1179 * 1180 * (We also register the sk_lock with the lock validator.) 1181 */ 1182 static inline void sock_lock_init(struct sock *sk) 1183 { 1184 sock_lock_init_class_and_name(sk, 1185 af_family_slock_key_strings[sk->sk_family], 1186 af_family_slock_keys + sk->sk_family, 1187 af_family_key_strings[sk->sk_family], 1188 af_family_keys + sk->sk_family); 1189 } 1190 1191 /* 1192 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1193 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1194 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1195 */ 1196 static void sock_copy(struct sock *nsk, const struct sock *osk) 1197 { 1198 #ifdef CONFIG_SECURITY_NETWORK 1199 void *sptr = nsk->sk_security; 1200 #endif 1201 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1202 1203 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1204 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1205 1206 #ifdef CONFIG_SECURITY_NETWORK 1207 nsk->sk_security = sptr; 1208 security_sk_clone(osk, nsk); 1209 #endif 1210 } 1211 1212 /* 1213 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes 1214 * un-modified. Special care is taken when initializing object to zero. 1215 */ 1216 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1217 { 1218 if (offsetof(struct sock, sk_node.next) != 0) 1219 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1220 memset(&sk->sk_node.pprev, 0, 1221 size - offsetof(struct sock, sk_node.pprev)); 1222 } 1223 1224 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size) 1225 { 1226 unsigned long nulls1, nulls2; 1227 1228 nulls1 = offsetof(struct sock, __sk_common.skc_node.next); 1229 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next); 1230 if (nulls1 > nulls2) 1231 swap(nulls1, nulls2); 1232 1233 if (nulls1 != 0) 1234 memset((char *)sk, 0, nulls1); 1235 memset((char *)sk + nulls1 + sizeof(void *), 0, 1236 nulls2 - nulls1 - sizeof(void *)); 1237 memset((char *)sk + nulls2 + sizeof(void *), 0, 1238 size - nulls2 - sizeof(void *)); 1239 } 1240 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls); 1241 1242 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1243 int family) 1244 { 1245 struct sock *sk; 1246 struct kmem_cache *slab; 1247 1248 slab = prot->slab; 1249 if (slab != NULL) { 1250 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1251 if (!sk) 1252 return sk; 1253 if (priority & __GFP_ZERO) { 1254 if (prot->clear_sk) 1255 prot->clear_sk(sk, prot->obj_size); 1256 else 1257 sk_prot_clear_nulls(sk, prot->obj_size); 1258 } 1259 } else 1260 sk = kmalloc(prot->obj_size, priority); 1261 1262 if (sk != NULL) { 1263 kmemcheck_annotate_bitfield(sk, flags); 1264 1265 if (security_sk_alloc(sk, family, priority)) 1266 goto out_free; 1267 1268 if (!try_module_get(prot->owner)) 1269 goto out_free_sec; 1270 sk_tx_queue_clear(sk); 1271 } 1272 1273 return sk; 1274 1275 out_free_sec: 1276 security_sk_free(sk); 1277 out_free: 1278 if (slab != NULL) 1279 kmem_cache_free(slab, sk); 1280 else 1281 kfree(sk); 1282 return NULL; 1283 } 1284 1285 static void sk_prot_free(struct proto *prot, struct sock *sk) 1286 { 1287 struct kmem_cache *slab; 1288 struct module *owner; 1289 1290 owner = prot->owner; 1291 slab = prot->slab; 1292 1293 security_sk_free(sk); 1294 if (slab != NULL) 1295 kmem_cache_free(slab, sk); 1296 else 1297 kfree(sk); 1298 module_put(owner); 1299 } 1300 1301 #if IS_ENABLED(CONFIG_NET_CLS_CGROUP) 1302 void sock_update_classid(struct sock *sk, struct task_struct *task) 1303 { 1304 u32 classid; 1305 1306 classid = task_cls_classid(task); 1307 if (classid != sk->sk_classid) 1308 sk->sk_classid = classid; 1309 } 1310 EXPORT_SYMBOL(sock_update_classid); 1311 #endif 1312 1313 #if IS_ENABLED(CONFIG_NETPRIO_CGROUP) 1314 void sock_update_netprioidx(struct sock *sk, struct task_struct *task) 1315 { 1316 if (in_interrupt()) 1317 return; 1318 1319 sk->sk_cgrp_prioidx = task_netprioidx(task); 1320 } 1321 EXPORT_SYMBOL_GPL(sock_update_netprioidx); 1322 #endif 1323 1324 /** 1325 * sk_alloc - All socket objects are allocated here 1326 * @net: the applicable net namespace 1327 * @family: protocol family 1328 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1329 * @prot: struct proto associated with this new sock instance 1330 */ 1331 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1332 struct proto *prot) 1333 { 1334 struct sock *sk; 1335 1336 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1337 if (sk) { 1338 sk->sk_family = family; 1339 /* 1340 * See comment in struct sock definition to understand 1341 * why we need sk_prot_creator -acme 1342 */ 1343 sk->sk_prot = sk->sk_prot_creator = prot; 1344 sock_lock_init(sk); 1345 sock_net_set(sk, get_net(net)); 1346 atomic_set(&sk->sk_wmem_alloc, 1); 1347 1348 sock_update_classid(sk, current); 1349 sock_update_netprioidx(sk, current); 1350 } 1351 1352 return sk; 1353 } 1354 EXPORT_SYMBOL(sk_alloc); 1355 1356 static void __sk_free(struct sock *sk) 1357 { 1358 struct sk_filter *filter; 1359 1360 if (sk->sk_destruct) 1361 sk->sk_destruct(sk); 1362 1363 filter = rcu_dereference_check(sk->sk_filter, 1364 atomic_read(&sk->sk_wmem_alloc) == 0); 1365 if (filter) { 1366 sk_filter_uncharge(sk, filter); 1367 RCU_INIT_POINTER(sk->sk_filter, NULL); 1368 } 1369 1370 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1371 1372 if (atomic_read(&sk->sk_omem_alloc)) 1373 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1374 __func__, atomic_read(&sk->sk_omem_alloc)); 1375 1376 if (sk->sk_peer_cred) 1377 put_cred(sk->sk_peer_cred); 1378 put_pid(sk->sk_peer_pid); 1379 put_net(sock_net(sk)); 1380 sk_prot_free(sk->sk_prot_creator, sk); 1381 } 1382 1383 void sk_free(struct sock *sk) 1384 { 1385 /* 1386 * We subtract one from sk_wmem_alloc and can know if 1387 * some packets are still in some tx queue. 1388 * If not null, sock_wfree() will call __sk_free(sk) later 1389 */ 1390 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1391 __sk_free(sk); 1392 } 1393 EXPORT_SYMBOL(sk_free); 1394 1395 /* 1396 * Last sock_put should drop reference to sk->sk_net. It has already 1397 * been dropped in sk_change_net. Taking reference to stopping namespace 1398 * is not an option. 1399 * Take reference to a socket to remove it from hash _alive_ and after that 1400 * destroy it in the context of init_net. 1401 */ 1402 void sk_release_kernel(struct sock *sk) 1403 { 1404 if (sk == NULL || sk->sk_socket == NULL) 1405 return; 1406 1407 sock_hold(sk); 1408 sock_release(sk->sk_socket); 1409 release_net(sock_net(sk)); 1410 sock_net_set(sk, get_net(&init_net)); 1411 sock_put(sk); 1412 } 1413 EXPORT_SYMBOL(sk_release_kernel); 1414 1415 static void sk_update_clone(const struct sock *sk, struct sock *newsk) 1416 { 1417 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1418 sock_update_memcg(newsk); 1419 } 1420 1421 /** 1422 * sk_clone_lock - clone a socket, and lock its clone 1423 * @sk: the socket to clone 1424 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1425 * 1426 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1427 */ 1428 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1429 { 1430 struct sock *newsk; 1431 1432 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1433 if (newsk != NULL) { 1434 struct sk_filter *filter; 1435 1436 sock_copy(newsk, sk); 1437 1438 /* SANITY */ 1439 get_net(sock_net(newsk)); 1440 sk_node_init(&newsk->sk_node); 1441 sock_lock_init(newsk); 1442 bh_lock_sock(newsk); 1443 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1444 newsk->sk_backlog.len = 0; 1445 1446 atomic_set(&newsk->sk_rmem_alloc, 0); 1447 /* 1448 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1449 */ 1450 atomic_set(&newsk->sk_wmem_alloc, 1); 1451 atomic_set(&newsk->sk_omem_alloc, 0); 1452 skb_queue_head_init(&newsk->sk_receive_queue); 1453 skb_queue_head_init(&newsk->sk_write_queue); 1454 #ifdef CONFIG_NET_DMA 1455 skb_queue_head_init(&newsk->sk_async_wait_queue); 1456 #endif 1457 1458 spin_lock_init(&newsk->sk_dst_lock); 1459 rwlock_init(&newsk->sk_callback_lock); 1460 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1461 af_callback_keys + newsk->sk_family, 1462 af_family_clock_key_strings[newsk->sk_family]); 1463 1464 newsk->sk_dst_cache = NULL; 1465 newsk->sk_wmem_queued = 0; 1466 newsk->sk_forward_alloc = 0; 1467 newsk->sk_send_head = NULL; 1468 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1469 1470 sock_reset_flag(newsk, SOCK_DONE); 1471 skb_queue_head_init(&newsk->sk_error_queue); 1472 1473 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1474 if (filter != NULL) 1475 sk_filter_charge(newsk, filter); 1476 1477 if (unlikely(xfrm_sk_clone_policy(newsk))) { 1478 /* It is still raw copy of parent, so invalidate 1479 * destructor and make plain sk_free() */ 1480 newsk->sk_destruct = NULL; 1481 bh_unlock_sock(newsk); 1482 sk_free(newsk); 1483 newsk = NULL; 1484 goto out; 1485 } 1486 1487 newsk->sk_err = 0; 1488 newsk->sk_priority = 0; 1489 /* 1490 * Before updating sk_refcnt, we must commit prior changes to memory 1491 * (Documentation/RCU/rculist_nulls.txt for details) 1492 */ 1493 smp_wmb(); 1494 atomic_set(&newsk->sk_refcnt, 2); 1495 1496 /* 1497 * Increment the counter in the same struct proto as the master 1498 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1499 * is the same as sk->sk_prot->socks, as this field was copied 1500 * with memcpy). 1501 * 1502 * This _changes_ the previous behaviour, where 1503 * tcp_create_openreq_child always was incrementing the 1504 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1505 * to be taken into account in all callers. -acme 1506 */ 1507 sk_refcnt_debug_inc(newsk); 1508 sk_set_socket(newsk, NULL); 1509 newsk->sk_wq = NULL; 1510 1511 sk_update_clone(sk, newsk); 1512 1513 if (newsk->sk_prot->sockets_allocated) 1514 sk_sockets_allocated_inc(newsk); 1515 1516 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1517 net_enable_timestamp(); 1518 } 1519 out: 1520 return newsk; 1521 } 1522 EXPORT_SYMBOL_GPL(sk_clone_lock); 1523 1524 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1525 { 1526 __sk_dst_set(sk, dst); 1527 sk->sk_route_caps = dst->dev->features; 1528 if (sk->sk_route_caps & NETIF_F_GSO) 1529 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1530 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1531 if (sk_can_gso(sk)) { 1532 if (dst->header_len) { 1533 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1534 } else { 1535 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1536 sk->sk_gso_max_size = dst->dev->gso_max_size; 1537 sk->sk_gso_max_segs = dst->dev->gso_max_segs; 1538 } 1539 } 1540 } 1541 EXPORT_SYMBOL_GPL(sk_setup_caps); 1542 1543 /* 1544 * Simple resource managers for sockets. 1545 */ 1546 1547 1548 /* 1549 * Write buffer destructor automatically called from kfree_skb. 1550 */ 1551 void sock_wfree(struct sk_buff *skb) 1552 { 1553 struct sock *sk = skb->sk; 1554 unsigned int len = skb->truesize; 1555 1556 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1557 /* 1558 * Keep a reference on sk_wmem_alloc, this will be released 1559 * after sk_write_space() call 1560 */ 1561 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1562 sk->sk_write_space(sk); 1563 len = 1; 1564 } 1565 /* 1566 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1567 * could not do because of in-flight packets 1568 */ 1569 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1570 __sk_free(sk); 1571 } 1572 EXPORT_SYMBOL(sock_wfree); 1573 1574 /* 1575 * Read buffer destructor automatically called from kfree_skb. 1576 */ 1577 void sock_rfree(struct sk_buff *skb) 1578 { 1579 struct sock *sk = skb->sk; 1580 unsigned int len = skb->truesize; 1581 1582 atomic_sub(len, &sk->sk_rmem_alloc); 1583 sk_mem_uncharge(sk, len); 1584 } 1585 EXPORT_SYMBOL(sock_rfree); 1586 1587 void sock_edemux(struct sk_buff *skb) 1588 { 1589 struct sock *sk = skb->sk; 1590 1591 #ifdef CONFIG_INET 1592 if (sk->sk_state == TCP_TIME_WAIT) 1593 inet_twsk_put(inet_twsk(sk)); 1594 else 1595 #endif 1596 sock_put(sk); 1597 } 1598 EXPORT_SYMBOL(sock_edemux); 1599 1600 kuid_t sock_i_uid(struct sock *sk) 1601 { 1602 kuid_t uid; 1603 1604 read_lock_bh(&sk->sk_callback_lock); 1605 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1606 read_unlock_bh(&sk->sk_callback_lock); 1607 return uid; 1608 } 1609 EXPORT_SYMBOL(sock_i_uid); 1610 1611 unsigned long sock_i_ino(struct sock *sk) 1612 { 1613 unsigned long ino; 1614 1615 read_lock_bh(&sk->sk_callback_lock); 1616 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1617 read_unlock_bh(&sk->sk_callback_lock); 1618 return ino; 1619 } 1620 EXPORT_SYMBOL(sock_i_ino); 1621 1622 /* 1623 * Allocate a skb from the socket's send buffer. 1624 */ 1625 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1626 gfp_t priority) 1627 { 1628 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1629 struct sk_buff *skb = alloc_skb(size, priority); 1630 if (skb) { 1631 skb_set_owner_w(skb, sk); 1632 return skb; 1633 } 1634 } 1635 return NULL; 1636 } 1637 EXPORT_SYMBOL(sock_wmalloc); 1638 1639 /* 1640 * Allocate a skb from the socket's receive buffer. 1641 */ 1642 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force, 1643 gfp_t priority) 1644 { 1645 if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) { 1646 struct sk_buff *skb = alloc_skb(size, priority); 1647 if (skb) { 1648 skb_set_owner_r(skb, sk); 1649 return skb; 1650 } 1651 } 1652 return NULL; 1653 } 1654 1655 /* 1656 * Allocate a memory block from the socket's option memory buffer. 1657 */ 1658 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1659 { 1660 if ((unsigned int)size <= sysctl_optmem_max && 1661 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1662 void *mem; 1663 /* First do the add, to avoid the race if kmalloc 1664 * might sleep. 1665 */ 1666 atomic_add(size, &sk->sk_omem_alloc); 1667 mem = kmalloc(size, priority); 1668 if (mem) 1669 return mem; 1670 atomic_sub(size, &sk->sk_omem_alloc); 1671 } 1672 return NULL; 1673 } 1674 EXPORT_SYMBOL(sock_kmalloc); 1675 1676 /* 1677 * Free an option memory block. 1678 */ 1679 void sock_kfree_s(struct sock *sk, void *mem, int size) 1680 { 1681 kfree(mem); 1682 atomic_sub(size, &sk->sk_omem_alloc); 1683 } 1684 EXPORT_SYMBOL(sock_kfree_s); 1685 1686 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1687 I think, these locks should be removed for datagram sockets. 1688 */ 1689 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1690 { 1691 DEFINE_WAIT(wait); 1692 1693 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1694 for (;;) { 1695 if (!timeo) 1696 break; 1697 if (signal_pending(current)) 1698 break; 1699 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1700 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1701 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1702 break; 1703 if (sk->sk_shutdown & SEND_SHUTDOWN) 1704 break; 1705 if (sk->sk_err) 1706 break; 1707 timeo = schedule_timeout(timeo); 1708 } 1709 finish_wait(sk_sleep(sk), &wait); 1710 return timeo; 1711 } 1712 1713 1714 /* 1715 * Generic send/receive buffer handlers 1716 */ 1717 1718 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1719 unsigned long data_len, int noblock, 1720 int *errcode) 1721 { 1722 struct sk_buff *skb; 1723 gfp_t gfp_mask; 1724 long timeo; 1725 int err; 1726 int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT; 1727 1728 err = -EMSGSIZE; 1729 if (npages > MAX_SKB_FRAGS) 1730 goto failure; 1731 1732 gfp_mask = sk->sk_allocation; 1733 if (gfp_mask & __GFP_WAIT) 1734 gfp_mask |= __GFP_REPEAT; 1735 1736 timeo = sock_sndtimeo(sk, noblock); 1737 while (1) { 1738 err = sock_error(sk); 1739 if (err != 0) 1740 goto failure; 1741 1742 err = -EPIPE; 1743 if (sk->sk_shutdown & SEND_SHUTDOWN) 1744 goto failure; 1745 1746 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1747 skb = alloc_skb(header_len, gfp_mask); 1748 if (skb) { 1749 int i; 1750 1751 /* No pages, we're done... */ 1752 if (!data_len) 1753 break; 1754 1755 skb->truesize += data_len; 1756 skb_shinfo(skb)->nr_frags = npages; 1757 for (i = 0; i < npages; i++) { 1758 struct page *page; 1759 1760 page = alloc_pages(sk->sk_allocation, 0); 1761 if (!page) { 1762 err = -ENOBUFS; 1763 skb_shinfo(skb)->nr_frags = i; 1764 kfree_skb(skb); 1765 goto failure; 1766 } 1767 1768 __skb_fill_page_desc(skb, i, 1769 page, 0, 1770 (data_len >= PAGE_SIZE ? 1771 PAGE_SIZE : 1772 data_len)); 1773 data_len -= PAGE_SIZE; 1774 } 1775 1776 /* Full success... */ 1777 break; 1778 } 1779 err = -ENOBUFS; 1780 goto failure; 1781 } 1782 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1783 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1784 err = -EAGAIN; 1785 if (!timeo) 1786 goto failure; 1787 if (signal_pending(current)) 1788 goto interrupted; 1789 timeo = sock_wait_for_wmem(sk, timeo); 1790 } 1791 1792 skb_set_owner_w(skb, sk); 1793 return skb; 1794 1795 interrupted: 1796 err = sock_intr_errno(timeo); 1797 failure: 1798 *errcode = err; 1799 return NULL; 1800 } 1801 EXPORT_SYMBOL(sock_alloc_send_pskb); 1802 1803 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1804 int noblock, int *errcode) 1805 { 1806 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode); 1807 } 1808 EXPORT_SYMBOL(sock_alloc_send_skb); 1809 1810 /* On 32bit arches, an skb frag is limited to 2^15 */ 1811 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1812 1813 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 1814 { 1815 int order; 1816 1817 if (pfrag->page) { 1818 if (atomic_read(&pfrag->page->_count) == 1) { 1819 pfrag->offset = 0; 1820 return true; 1821 } 1822 if (pfrag->offset < pfrag->size) 1823 return true; 1824 put_page(pfrag->page); 1825 } 1826 1827 /* We restrict high order allocations to users that can afford to wait */ 1828 order = (sk->sk_allocation & __GFP_WAIT) ? SKB_FRAG_PAGE_ORDER : 0; 1829 1830 do { 1831 gfp_t gfp = sk->sk_allocation; 1832 1833 if (order) 1834 gfp |= __GFP_COMP | __GFP_NOWARN; 1835 pfrag->page = alloc_pages(gfp, order); 1836 if (likely(pfrag->page)) { 1837 pfrag->offset = 0; 1838 pfrag->size = PAGE_SIZE << order; 1839 return true; 1840 } 1841 } while (--order >= 0); 1842 1843 sk_enter_memory_pressure(sk); 1844 sk_stream_moderate_sndbuf(sk); 1845 return false; 1846 } 1847 EXPORT_SYMBOL(sk_page_frag_refill); 1848 1849 static void __lock_sock(struct sock *sk) 1850 __releases(&sk->sk_lock.slock) 1851 __acquires(&sk->sk_lock.slock) 1852 { 1853 DEFINE_WAIT(wait); 1854 1855 for (;;) { 1856 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 1857 TASK_UNINTERRUPTIBLE); 1858 spin_unlock_bh(&sk->sk_lock.slock); 1859 schedule(); 1860 spin_lock_bh(&sk->sk_lock.slock); 1861 if (!sock_owned_by_user(sk)) 1862 break; 1863 } 1864 finish_wait(&sk->sk_lock.wq, &wait); 1865 } 1866 1867 static void __release_sock(struct sock *sk) 1868 __releases(&sk->sk_lock.slock) 1869 __acquires(&sk->sk_lock.slock) 1870 { 1871 struct sk_buff *skb = sk->sk_backlog.head; 1872 1873 do { 1874 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 1875 bh_unlock_sock(sk); 1876 1877 do { 1878 struct sk_buff *next = skb->next; 1879 1880 prefetch(next); 1881 WARN_ON_ONCE(skb_dst_is_noref(skb)); 1882 skb->next = NULL; 1883 sk_backlog_rcv(sk, skb); 1884 1885 /* 1886 * We are in process context here with softirqs 1887 * disabled, use cond_resched_softirq() to preempt. 1888 * This is safe to do because we've taken the backlog 1889 * queue private: 1890 */ 1891 cond_resched_softirq(); 1892 1893 skb = next; 1894 } while (skb != NULL); 1895 1896 bh_lock_sock(sk); 1897 } while ((skb = sk->sk_backlog.head) != NULL); 1898 1899 /* 1900 * Doing the zeroing here guarantee we can not loop forever 1901 * while a wild producer attempts to flood us. 1902 */ 1903 sk->sk_backlog.len = 0; 1904 } 1905 1906 /** 1907 * sk_wait_data - wait for data to arrive at sk_receive_queue 1908 * @sk: sock to wait on 1909 * @timeo: for how long 1910 * 1911 * Now socket state including sk->sk_err is changed only under lock, 1912 * hence we may omit checks after joining wait queue. 1913 * We check receive queue before schedule() only as optimization; 1914 * it is very likely that release_sock() added new data. 1915 */ 1916 int sk_wait_data(struct sock *sk, long *timeo) 1917 { 1918 int rc; 1919 DEFINE_WAIT(wait); 1920 1921 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1922 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1923 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); 1924 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1925 finish_wait(sk_sleep(sk), &wait); 1926 return rc; 1927 } 1928 EXPORT_SYMBOL(sk_wait_data); 1929 1930 /** 1931 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 1932 * @sk: socket 1933 * @size: memory size to allocate 1934 * @kind: allocation type 1935 * 1936 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 1937 * rmem allocation. This function assumes that protocols which have 1938 * memory_pressure use sk_wmem_queued as write buffer accounting. 1939 */ 1940 int __sk_mem_schedule(struct sock *sk, int size, int kind) 1941 { 1942 struct proto *prot = sk->sk_prot; 1943 int amt = sk_mem_pages(size); 1944 long allocated; 1945 int parent_status = UNDER_LIMIT; 1946 1947 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; 1948 1949 allocated = sk_memory_allocated_add(sk, amt, &parent_status); 1950 1951 /* Under limit. */ 1952 if (parent_status == UNDER_LIMIT && 1953 allocated <= sk_prot_mem_limits(sk, 0)) { 1954 sk_leave_memory_pressure(sk); 1955 return 1; 1956 } 1957 1958 /* Under pressure. (we or our parents) */ 1959 if ((parent_status > SOFT_LIMIT) || 1960 allocated > sk_prot_mem_limits(sk, 1)) 1961 sk_enter_memory_pressure(sk); 1962 1963 /* Over hard limit (we or our parents) */ 1964 if ((parent_status == OVER_LIMIT) || 1965 (allocated > sk_prot_mem_limits(sk, 2))) 1966 goto suppress_allocation; 1967 1968 /* guarantee minimum buffer size under pressure */ 1969 if (kind == SK_MEM_RECV) { 1970 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 1971 return 1; 1972 1973 } else { /* SK_MEM_SEND */ 1974 if (sk->sk_type == SOCK_STREAM) { 1975 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 1976 return 1; 1977 } else if (atomic_read(&sk->sk_wmem_alloc) < 1978 prot->sysctl_wmem[0]) 1979 return 1; 1980 } 1981 1982 if (sk_has_memory_pressure(sk)) { 1983 int alloc; 1984 1985 if (!sk_under_memory_pressure(sk)) 1986 return 1; 1987 alloc = sk_sockets_allocated_read_positive(sk); 1988 if (sk_prot_mem_limits(sk, 2) > alloc * 1989 sk_mem_pages(sk->sk_wmem_queued + 1990 atomic_read(&sk->sk_rmem_alloc) + 1991 sk->sk_forward_alloc)) 1992 return 1; 1993 } 1994 1995 suppress_allocation: 1996 1997 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 1998 sk_stream_moderate_sndbuf(sk); 1999 2000 /* Fail only if socket is _under_ its sndbuf. 2001 * In this case we cannot block, so that we have to fail. 2002 */ 2003 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2004 return 1; 2005 } 2006 2007 trace_sock_exceed_buf_limit(sk, prot, allocated); 2008 2009 /* Alas. Undo changes. */ 2010 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM; 2011 2012 sk_memory_allocated_sub(sk, amt); 2013 2014 return 0; 2015 } 2016 EXPORT_SYMBOL(__sk_mem_schedule); 2017 2018 /** 2019 * __sk_reclaim - reclaim memory_allocated 2020 * @sk: socket 2021 */ 2022 void __sk_mem_reclaim(struct sock *sk) 2023 { 2024 sk_memory_allocated_sub(sk, 2025 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT); 2026 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1; 2027 2028 if (sk_under_memory_pressure(sk) && 2029 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2030 sk_leave_memory_pressure(sk); 2031 } 2032 EXPORT_SYMBOL(__sk_mem_reclaim); 2033 2034 2035 /* 2036 * Set of default routines for initialising struct proto_ops when 2037 * the protocol does not support a particular function. In certain 2038 * cases where it makes no sense for a protocol to have a "do nothing" 2039 * function, some default processing is provided. 2040 */ 2041 2042 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2043 { 2044 return -EOPNOTSUPP; 2045 } 2046 EXPORT_SYMBOL(sock_no_bind); 2047 2048 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2049 int len, int flags) 2050 { 2051 return -EOPNOTSUPP; 2052 } 2053 EXPORT_SYMBOL(sock_no_connect); 2054 2055 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2056 { 2057 return -EOPNOTSUPP; 2058 } 2059 EXPORT_SYMBOL(sock_no_socketpair); 2060 2061 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 2062 { 2063 return -EOPNOTSUPP; 2064 } 2065 EXPORT_SYMBOL(sock_no_accept); 2066 2067 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2068 int *len, int peer) 2069 { 2070 return -EOPNOTSUPP; 2071 } 2072 EXPORT_SYMBOL(sock_no_getname); 2073 2074 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 2075 { 2076 return 0; 2077 } 2078 EXPORT_SYMBOL(sock_no_poll); 2079 2080 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2081 { 2082 return -EOPNOTSUPP; 2083 } 2084 EXPORT_SYMBOL(sock_no_ioctl); 2085 2086 int sock_no_listen(struct socket *sock, int backlog) 2087 { 2088 return -EOPNOTSUPP; 2089 } 2090 EXPORT_SYMBOL(sock_no_listen); 2091 2092 int sock_no_shutdown(struct socket *sock, int how) 2093 { 2094 return -EOPNOTSUPP; 2095 } 2096 EXPORT_SYMBOL(sock_no_shutdown); 2097 2098 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2099 char __user *optval, unsigned int optlen) 2100 { 2101 return -EOPNOTSUPP; 2102 } 2103 EXPORT_SYMBOL(sock_no_setsockopt); 2104 2105 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2106 char __user *optval, int __user *optlen) 2107 { 2108 return -EOPNOTSUPP; 2109 } 2110 EXPORT_SYMBOL(sock_no_getsockopt); 2111 2112 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2113 size_t len) 2114 { 2115 return -EOPNOTSUPP; 2116 } 2117 EXPORT_SYMBOL(sock_no_sendmsg); 2118 2119 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2120 size_t len, int flags) 2121 { 2122 return -EOPNOTSUPP; 2123 } 2124 EXPORT_SYMBOL(sock_no_recvmsg); 2125 2126 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2127 { 2128 /* Mirror missing mmap method error code */ 2129 return -ENODEV; 2130 } 2131 EXPORT_SYMBOL(sock_no_mmap); 2132 2133 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2134 { 2135 ssize_t res; 2136 struct msghdr msg = {.msg_flags = flags}; 2137 struct kvec iov; 2138 char *kaddr = kmap(page); 2139 iov.iov_base = kaddr + offset; 2140 iov.iov_len = size; 2141 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2142 kunmap(page); 2143 return res; 2144 } 2145 EXPORT_SYMBOL(sock_no_sendpage); 2146 2147 /* 2148 * Default Socket Callbacks 2149 */ 2150 2151 static void sock_def_wakeup(struct sock *sk) 2152 { 2153 struct socket_wq *wq; 2154 2155 rcu_read_lock(); 2156 wq = rcu_dereference(sk->sk_wq); 2157 if (wq_has_sleeper(wq)) 2158 wake_up_interruptible_all(&wq->wait); 2159 rcu_read_unlock(); 2160 } 2161 2162 static void sock_def_error_report(struct sock *sk) 2163 { 2164 struct socket_wq *wq; 2165 2166 rcu_read_lock(); 2167 wq = rcu_dereference(sk->sk_wq); 2168 if (wq_has_sleeper(wq)) 2169 wake_up_interruptible_poll(&wq->wait, POLLERR); 2170 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2171 rcu_read_unlock(); 2172 } 2173 2174 static void sock_def_readable(struct sock *sk, int len) 2175 { 2176 struct socket_wq *wq; 2177 2178 rcu_read_lock(); 2179 wq = rcu_dereference(sk->sk_wq); 2180 if (wq_has_sleeper(wq)) 2181 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI | 2182 POLLRDNORM | POLLRDBAND); 2183 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2184 rcu_read_unlock(); 2185 } 2186 2187 static void sock_def_write_space(struct sock *sk) 2188 { 2189 struct socket_wq *wq; 2190 2191 rcu_read_lock(); 2192 2193 /* Do not wake up a writer until he can make "significant" 2194 * progress. --DaveM 2195 */ 2196 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2197 wq = rcu_dereference(sk->sk_wq); 2198 if (wq_has_sleeper(wq)) 2199 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 2200 POLLWRNORM | POLLWRBAND); 2201 2202 /* Should agree with poll, otherwise some programs break */ 2203 if (sock_writeable(sk)) 2204 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2205 } 2206 2207 rcu_read_unlock(); 2208 } 2209 2210 static void sock_def_destruct(struct sock *sk) 2211 { 2212 kfree(sk->sk_protinfo); 2213 } 2214 2215 void sk_send_sigurg(struct sock *sk) 2216 { 2217 if (sk->sk_socket && sk->sk_socket->file) 2218 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2219 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2220 } 2221 EXPORT_SYMBOL(sk_send_sigurg); 2222 2223 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2224 unsigned long expires) 2225 { 2226 if (!mod_timer(timer, expires)) 2227 sock_hold(sk); 2228 } 2229 EXPORT_SYMBOL(sk_reset_timer); 2230 2231 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2232 { 2233 if (del_timer(timer)) 2234 __sock_put(sk); 2235 } 2236 EXPORT_SYMBOL(sk_stop_timer); 2237 2238 void sock_init_data(struct socket *sock, struct sock *sk) 2239 { 2240 skb_queue_head_init(&sk->sk_receive_queue); 2241 skb_queue_head_init(&sk->sk_write_queue); 2242 skb_queue_head_init(&sk->sk_error_queue); 2243 #ifdef CONFIG_NET_DMA 2244 skb_queue_head_init(&sk->sk_async_wait_queue); 2245 #endif 2246 2247 sk->sk_send_head = NULL; 2248 2249 init_timer(&sk->sk_timer); 2250 2251 sk->sk_allocation = GFP_KERNEL; 2252 sk->sk_rcvbuf = sysctl_rmem_default; 2253 sk->sk_sndbuf = sysctl_wmem_default; 2254 sk->sk_state = TCP_CLOSE; 2255 sk_set_socket(sk, sock); 2256 2257 sock_set_flag(sk, SOCK_ZAPPED); 2258 2259 if (sock) { 2260 sk->sk_type = sock->type; 2261 sk->sk_wq = sock->wq; 2262 sock->sk = sk; 2263 } else 2264 sk->sk_wq = NULL; 2265 2266 spin_lock_init(&sk->sk_dst_lock); 2267 rwlock_init(&sk->sk_callback_lock); 2268 lockdep_set_class_and_name(&sk->sk_callback_lock, 2269 af_callback_keys + sk->sk_family, 2270 af_family_clock_key_strings[sk->sk_family]); 2271 2272 sk->sk_state_change = sock_def_wakeup; 2273 sk->sk_data_ready = sock_def_readable; 2274 sk->sk_write_space = sock_def_write_space; 2275 sk->sk_error_report = sock_def_error_report; 2276 sk->sk_destruct = sock_def_destruct; 2277 2278 sk->sk_frag.page = NULL; 2279 sk->sk_frag.offset = 0; 2280 sk->sk_peek_off = -1; 2281 2282 sk->sk_peer_pid = NULL; 2283 sk->sk_peer_cred = NULL; 2284 sk->sk_write_pending = 0; 2285 sk->sk_rcvlowat = 1; 2286 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2287 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2288 2289 sk->sk_stamp = ktime_set(-1L, 0); 2290 2291 /* 2292 * Before updating sk_refcnt, we must commit prior changes to memory 2293 * (Documentation/RCU/rculist_nulls.txt for details) 2294 */ 2295 smp_wmb(); 2296 atomic_set(&sk->sk_refcnt, 1); 2297 atomic_set(&sk->sk_drops, 0); 2298 } 2299 EXPORT_SYMBOL(sock_init_data); 2300 2301 void lock_sock_nested(struct sock *sk, int subclass) 2302 { 2303 might_sleep(); 2304 spin_lock_bh(&sk->sk_lock.slock); 2305 if (sk->sk_lock.owned) 2306 __lock_sock(sk); 2307 sk->sk_lock.owned = 1; 2308 spin_unlock(&sk->sk_lock.slock); 2309 /* 2310 * The sk_lock has mutex_lock() semantics here: 2311 */ 2312 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2313 local_bh_enable(); 2314 } 2315 EXPORT_SYMBOL(lock_sock_nested); 2316 2317 void release_sock(struct sock *sk) 2318 { 2319 /* 2320 * The sk_lock has mutex_unlock() semantics: 2321 */ 2322 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 2323 2324 spin_lock_bh(&sk->sk_lock.slock); 2325 if (sk->sk_backlog.tail) 2326 __release_sock(sk); 2327 2328 if (sk->sk_prot->release_cb) 2329 sk->sk_prot->release_cb(sk); 2330 2331 sk->sk_lock.owned = 0; 2332 if (waitqueue_active(&sk->sk_lock.wq)) 2333 wake_up(&sk->sk_lock.wq); 2334 spin_unlock_bh(&sk->sk_lock.slock); 2335 } 2336 EXPORT_SYMBOL(release_sock); 2337 2338 /** 2339 * lock_sock_fast - fast version of lock_sock 2340 * @sk: socket 2341 * 2342 * This version should be used for very small section, where process wont block 2343 * return false if fast path is taken 2344 * sk_lock.slock locked, owned = 0, BH disabled 2345 * return true if slow path is taken 2346 * sk_lock.slock unlocked, owned = 1, BH enabled 2347 */ 2348 bool lock_sock_fast(struct sock *sk) 2349 { 2350 might_sleep(); 2351 spin_lock_bh(&sk->sk_lock.slock); 2352 2353 if (!sk->sk_lock.owned) 2354 /* 2355 * Note : We must disable BH 2356 */ 2357 return false; 2358 2359 __lock_sock(sk); 2360 sk->sk_lock.owned = 1; 2361 spin_unlock(&sk->sk_lock.slock); 2362 /* 2363 * The sk_lock has mutex_lock() semantics here: 2364 */ 2365 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2366 local_bh_enable(); 2367 return true; 2368 } 2369 EXPORT_SYMBOL(lock_sock_fast); 2370 2371 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2372 { 2373 struct timeval tv; 2374 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2375 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2376 tv = ktime_to_timeval(sk->sk_stamp); 2377 if (tv.tv_sec == -1) 2378 return -ENOENT; 2379 if (tv.tv_sec == 0) { 2380 sk->sk_stamp = ktime_get_real(); 2381 tv = ktime_to_timeval(sk->sk_stamp); 2382 } 2383 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2384 } 2385 EXPORT_SYMBOL(sock_get_timestamp); 2386 2387 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2388 { 2389 struct timespec ts; 2390 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2391 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2392 ts = ktime_to_timespec(sk->sk_stamp); 2393 if (ts.tv_sec == -1) 2394 return -ENOENT; 2395 if (ts.tv_sec == 0) { 2396 sk->sk_stamp = ktime_get_real(); 2397 ts = ktime_to_timespec(sk->sk_stamp); 2398 } 2399 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2400 } 2401 EXPORT_SYMBOL(sock_get_timestampns); 2402 2403 void sock_enable_timestamp(struct sock *sk, int flag) 2404 { 2405 if (!sock_flag(sk, flag)) { 2406 unsigned long previous_flags = sk->sk_flags; 2407 2408 sock_set_flag(sk, flag); 2409 /* 2410 * we just set one of the two flags which require net 2411 * time stamping, but time stamping might have been on 2412 * already because of the other one 2413 */ 2414 if (!(previous_flags & SK_FLAGS_TIMESTAMP)) 2415 net_enable_timestamp(); 2416 } 2417 } 2418 2419 /* 2420 * Get a socket option on an socket. 2421 * 2422 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2423 * asynchronous errors should be reported by getsockopt. We assume 2424 * this means if you specify SO_ERROR (otherwise whats the point of it). 2425 */ 2426 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2427 char __user *optval, int __user *optlen) 2428 { 2429 struct sock *sk = sock->sk; 2430 2431 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2432 } 2433 EXPORT_SYMBOL(sock_common_getsockopt); 2434 2435 #ifdef CONFIG_COMPAT 2436 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2437 char __user *optval, int __user *optlen) 2438 { 2439 struct sock *sk = sock->sk; 2440 2441 if (sk->sk_prot->compat_getsockopt != NULL) 2442 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2443 optval, optlen); 2444 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2445 } 2446 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2447 #endif 2448 2449 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, 2450 struct msghdr *msg, size_t size, int flags) 2451 { 2452 struct sock *sk = sock->sk; 2453 int addr_len = 0; 2454 int err; 2455 2456 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT, 2457 flags & ~MSG_DONTWAIT, &addr_len); 2458 if (err >= 0) 2459 msg->msg_namelen = addr_len; 2460 return err; 2461 } 2462 EXPORT_SYMBOL(sock_common_recvmsg); 2463 2464 /* 2465 * Set socket options on an inet socket. 2466 */ 2467 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2468 char __user *optval, unsigned int optlen) 2469 { 2470 struct sock *sk = sock->sk; 2471 2472 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2473 } 2474 EXPORT_SYMBOL(sock_common_setsockopt); 2475 2476 #ifdef CONFIG_COMPAT 2477 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2478 char __user *optval, unsigned int optlen) 2479 { 2480 struct sock *sk = sock->sk; 2481 2482 if (sk->sk_prot->compat_setsockopt != NULL) 2483 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2484 optval, optlen); 2485 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2486 } 2487 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2488 #endif 2489 2490 void sk_common_release(struct sock *sk) 2491 { 2492 if (sk->sk_prot->destroy) 2493 sk->sk_prot->destroy(sk); 2494 2495 /* 2496 * Observation: when sock_common_release is called, processes have 2497 * no access to socket. But net still has. 2498 * Step one, detach it from networking: 2499 * 2500 * A. Remove from hash tables. 2501 */ 2502 2503 sk->sk_prot->unhash(sk); 2504 2505 /* 2506 * In this point socket cannot receive new packets, but it is possible 2507 * that some packets are in flight because some CPU runs receiver and 2508 * did hash table lookup before we unhashed socket. They will achieve 2509 * receive queue and will be purged by socket destructor. 2510 * 2511 * Also we still have packets pending on receive queue and probably, 2512 * our own packets waiting in device queues. sock_destroy will drain 2513 * receive queue, but transmitted packets will delay socket destruction 2514 * until the last reference will be released. 2515 */ 2516 2517 sock_orphan(sk); 2518 2519 xfrm_sk_free_policy(sk); 2520 2521 sk_refcnt_debug_release(sk); 2522 2523 if (sk->sk_frag.page) { 2524 put_page(sk->sk_frag.page); 2525 sk->sk_frag.page = NULL; 2526 } 2527 2528 sock_put(sk); 2529 } 2530 EXPORT_SYMBOL(sk_common_release); 2531 2532 #ifdef CONFIG_PROC_FS 2533 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2534 struct prot_inuse { 2535 int val[PROTO_INUSE_NR]; 2536 }; 2537 2538 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2539 2540 #ifdef CONFIG_NET_NS 2541 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2542 { 2543 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2544 } 2545 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2546 2547 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2548 { 2549 int cpu, idx = prot->inuse_idx; 2550 int res = 0; 2551 2552 for_each_possible_cpu(cpu) 2553 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2554 2555 return res >= 0 ? res : 0; 2556 } 2557 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2558 2559 static int __net_init sock_inuse_init_net(struct net *net) 2560 { 2561 net->core.inuse = alloc_percpu(struct prot_inuse); 2562 return net->core.inuse ? 0 : -ENOMEM; 2563 } 2564 2565 static void __net_exit sock_inuse_exit_net(struct net *net) 2566 { 2567 free_percpu(net->core.inuse); 2568 } 2569 2570 static struct pernet_operations net_inuse_ops = { 2571 .init = sock_inuse_init_net, 2572 .exit = sock_inuse_exit_net, 2573 }; 2574 2575 static __init int net_inuse_init(void) 2576 { 2577 if (register_pernet_subsys(&net_inuse_ops)) 2578 panic("Cannot initialize net inuse counters"); 2579 2580 return 0; 2581 } 2582 2583 core_initcall(net_inuse_init); 2584 #else 2585 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2586 2587 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2588 { 2589 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2590 } 2591 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2592 2593 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2594 { 2595 int cpu, idx = prot->inuse_idx; 2596 int res = 0; 2597 2598 for_each_possible_cpu(cpu) 2599 res += per_cpu(prot_inuse, cpu).val[idx]; 2600 2601 return res >= 0 ? res : 0; 2602 } 2603 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2604 #endif 2605 2606 static void assign_proto_idx(struct proto *prot) 2607 { 2608 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2609 2610 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2611 pr_err("PROTO_INUSE_NR exhausted\n"); 2612 return; 2613 } 2614 2615 set_bit(prot->inuse_idx, proto_inuse_idx); 2616 } 2617 2618 static void release_proto_idx(struct proto *prot) 2619 { 2620 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2621 clear_bit(prot->inuse_idx, proto_inuse_idx); 2622 } 2623 #else 2624 static inline void assign_proto_idx(struct proto *prot) 2625 { 2626 } 2627 2628 static inline void release_proto_idx(struct proto *prot) 2629 { 2630 } 2631 #endif 2632 2633 int proto_register(struct proto *prot, int alloc_slab) 2634 { 2635 if (alloc_slab) { 2636 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2637 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2638 NULL); 2639 2640 if (prot->slab == NULL) { 2641 pr_crit("%s: Can't create sock SLAB cache!\n", 2642 prot->name); 2643 goto out; 2644 } 2645 2646 if (prot->rsk_prot != NULL) { 2647 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name); 2648 if (prot->rsk_prot->slab_name == NULL) 2649 goto out_free_sock_slab; 2650 2651 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name, 2652 prot->rsk_prot->obj_size, 0, 2653 SLAB_HWCACHE_ALIGN, NULL); 2654 2655 if (prot->rsk_prot->slab == NULL) { 2656 pr_crit("%s: Can't create request sock SLAB cache!\n", 2657 prot->name); 2658 goto out_free_request_sock_slab_name; 2659 } 2660 } 2661 2662 if (prot->twsk_prot != NULL) { 2663 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2664 2665 if (prot->twsk_prot->twsk_slab_name == NULL) 2666 goto out_free_request_sock_slab; 2667 2668 prot->twsk_prot->twsk_slab = 2669 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2670 prot->twsk_prot->twsk_obj_size, 2671 0, 2672 SLAB_HWCACHE_ALIGN | 2673 prot->slab_flags, 2674 NULL); 2675 if (prot->twsk_prot->twsk_slab == NULL) 2676 goto out_free_timewait_sock_slab_name; 2677 } 2678 } 2679 2680 mutex_lock(&proto_list_mutex); 2681 list_add(&prot->node, &proto_list); 2682 assign_proto_idx(prot); 2683 mutex_unlock(&proto_list_mutex); 2684 return 0; 2685 2686 out_free_timewait_sock_slab_name: 2687 kfree(prot->twsk_prot->twsk_slab_name); 2688 out_free_request_sock_slab: 2689 if (prot->rsk_prot && prot->rsk_prot->slab) { 2690 kmem_cache_destroy(prot->rsk_prot->slab); 2691 prot->rsk_prot->slab = NULL; 2692 } 2693 out_free_request_sock_slab_name: 2694 if (prot->rsk_prot) 2695 kfree(prot->rsk_prot->slab_name); 2696 out_free_sock_slab: 2697 kmem_cache_destroy(prot->slab); 2698 prot->slab = NULL; 2699 out: 2700 return -ENOBUFS; 2701 } 2702 EXPORT_SYMBOL(proto_register); 2703 2704 void proto_unregister(struct proto *prot) 2705 { 2706 mutex_lock(&proto_list_mutex); 2707 release_proto_idx(prot); 2708 list_del(&prot->node); 2709 mutex_unlock(&proto_list_mutex); 2710 2711 if (prot->slab != NULL) { 2712 kmem_cache_destroy(prot->slab); 2713 prot->slab = NULL; 2714 } 2715 2716 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) { 2717 kmem_cache_destroy(prot->rsk_prot->slab); 2718 kfree(prot->rsk_prot->slab_name); 2719 prot->rsk_prot->slab = NULL; 2720 } 2721 2722 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2723 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2724 kfree(prot->twsk_prot->twsk_slab_name); 2725 prot->twsk_prot->twsk_slab = NULL; 2726 } 2727 } 2728 EXPORT_SYMBOL(proto_unregister); 2729 2730 #ifdef CONFIG_PROC_FS 2731 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2732 __acquires(proto_list_mutex) 2733 { 2734 mutex_lock(&proto_list_mutex); 2735 return seq_list_start_head(&proto_list, *pos); 2736 } 2737 2738 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2739 { 2740 return seq_list_next(v, &proto_list, pos); 2741 } 2742 2743 static void proto_seq_stop(struct seq_file *seq, void *v) 2744 __releases(proto_list_mutex) 2745 { 2746 mutex_unlock(&proto_list_mutex); 2747 } 2748 2749 static char proto_method_implemented(const void *method) 2750 { 2751 return method == NULL ? 'n' : 'y'; 2752 } 2753 static long sock_prot_memory_allocated(struct proto *proto) 2754 { 2755 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 2756 } 2757 2758 static char *sock_prot_memory_pressure(struct proto *proto) 2759 { 2760 return proto->memory_pressure != NULL ? 2761 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 2762 } 2763 2764 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 2765 { 2766 2767 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 2768 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 2769 proto->name, 2770 proto->obj_size, 2771 sock_prot_inuse_get(seq_file_net(seq), proto), 2772 sock_prot_memory_allocated(proto), 2773 sock_prot_memory_pressure(proto), 2774 proto->max_header, 2775 proto->slab == NULL ? "no" : "yes", 2776 module_name(proto->owner), 2777 proto_method_implemented(proto->close), 2778 proto_method_implemented(proto->connect), 2779 proto_method_implemented(proto->disconnect), 2780 proto_method_implemented(proto->accept), 2781 proto_method_implemented(proto->ioctl), 2782 proto_method_implemented(proto->init), 2783 proto_method_implemented(proto->destroy), 2784 proto_method_implemented(proto->shutdown), 2785 proto_method_implemented(proto->setsockopt), 2786 proto_method_implemented(proto->getsockopt), 2787 proto_method_implemented(proto->sendmsg), 2788 proto_method_implemented(proto->recvmsg), 2789 proto_method_implemented(proto->sendpage), 2790 proto_method_implemented(proto->bind), 2791 proto_method_implemented(proto->backlog_rcv), 2792 proto_method_implemented(proto->hash), 2793 proto_method_implemented(proto->unhash), 2794 proto_method_implemented(proto->get_port), 2795 proto_method_implemented(proto->enter_memory_pressure)); 2796 } 2797 2798 static int proto_seq_show(struct seq_file *seq, void *v) 2799 { 2800 if (v == &proto_list) 2801 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 2802 "protocol", 2803 "size", 2804 "sockets", 2805 "memory", 2806 "press", 2807 "maxhdr", 2808 "slab", 2809 "module", 2810 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 2811 else 2812 proto_seq_printf(seq, list_entry(v, struct proto, node)); 2813 return 0; 2814 } 2815 2816 static const struct seq_operations proto_seq_ops = { 2817 .start = proto_seq_start, 2818 .next = proto_seq_next, 2819 .stop = proto_seq_stop, 2820 .show = proto_seq_show, 2821 }; 2822 2823 static int proto_seq_open(struct inode *inode, struct file *file) 2824 { 2825 return seq_open_net(inode, file, &proto_seq_ops, 2826 sizeof(struct seq_net_private)); 2827 } 2828 2829 static const struct file_operations proto_seq_fops = { 2830 .owner = THIS_MODULE, 2831 .open = proto_seq_open, 2832 .read = seq_read, 2833 .llseek = seq_lseek, 2834 .release = seq_release_net, 2835 }; 2836 2837 static __net_init int proto_init_net(struct net *net) 2838 { 2839 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops)) 2840 return -ENOMEM; 2841 2842 return 0; 2843 } 2844 2845 static __net_exit void proto_exit_net(struct net *net) 2846 { 2847 remove_proc_entry("protocols", net->proc_net); 2848 } 2849 2850 2851 static __net_initdata struct pernet_operations proto_net_ops = { 2852 .init = proto_init_net, 2853 .exit = proto_exit_net, 2854 }; 2855 2856 static int __init proto_init(void) 2857 { 2858 return register_pernet_subsys(&proto_net_ops); 2859 } 2860 2861 subsys_initcall(proto_init); 2862 2863 #endif /* PROC_FS */ 2864