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 case SO_SELECT_ERR_QUEUE: 911 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 912 break; 913 914 default: 915 ret = -ENOPROTOOPT; 916 break; 917 } 918 release_sock(sk); 919 return ret; 920 } 921 EXPORT_SYMBOL(sock_setsockopt); 922 923 924 void cred_to_ucred(struct pid *pid, const struct cred *cred, 925 struct ucred *ucred) 926 { 927 ucred->pid = pid_vnr(pid); 928 ucred->uid = ucred->gid = -1; 929 if (cred) { 930 struct user_namespace *current_ns = current_user_ns(); 931 932 ucred->uid = from_kuid_munged(current_ns, cred->euid); 933 ucred->gid = from_kgid_munged(current_ns, cred->egid); 934 } 935 } 936 EXPORT_SYMBOL_GPL(cred_to_ucred); 937 938 int sock_getsockopt(struct socket *sock, int level, int optname, 939 char __user *optval, int __user *optlen) 940 { 941 struct sock *sk = sock->sk; 942 943 union { 944 int val; 945 struct linger ling; 946 struct timeval tm; 947 } v; 948 949 int lv = sizeof(int); 950 int len; 951 952 if (get_user(len, optlen)) 953 return -EFAULT; 954 if (len < 0) 955 return -EINVAL; 956 957 memset(&v, 0, sizeof(v)); 958 959 switch (optname) { 960 case SO_DEBUG: 961 v.val = sock_flag(sk, SOCK_DBG); 962 break; 963 964 case SO_DONTROUTE: 965 v.val = sock_flag(sk, SOCK_LOCALROUTE); 966 break; 967 968 case SO_BROADCAST: 969 v.val = sock_flag(sk, SOCK_BROADCAST); 970 break; 971 972 case SO_SNDBUF: 973 v.val = sk->sk_sndbuf; 974 break; 975 976 case SO_RCVBUF: 977 v.val = sk->sk_rcvbuf; 978 break; 979 980 case SO_REUSEADDR: 981 v.val = sk->sk_reuse; 982 break; 983 984 case SO_REUSEPORT: 985 v.val = sk->sk_reuseport; 986 break; 987 988 case SO_KEEPALIVE: 989 v.val = sock_flag(sk, SOCK_KEEPOPEN); 990 break; 991 992 case SO_TYPE: 993 v.val = sk->sk_type; 994 break; 995 996 case SO_PROTOCOL: 997 v.val = sk->sk_protocol; 998 break; 999 1000 case SO_DOMAIN: 1001 v.val = sk->sk_family; 1002 break; 1003 1004 case SO_ERROR: 1005 v.val = -sock_error(sk); 1006 if (v.val == 0) 1007 v.val = xchg(&sk->sk_err_soft, 0); 1008 break; 1009 1010 case SO_OOBINLINE: 1011 v.val = sock_flag(sk, SOCK_URGINLINE); 1012 break; 1013 1014 case SO_NO_CHECK: 1015 v.val = sk->sk_no_check; 1016 break; 1017 1018 case SO_PRIORITY: 1019 v.val = sk->sk_priority; 1020 break; 1021 1022 case SO_LINGER: 1023 lv = sizeof(v.ling); 1024 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1025 v.ling.l_linger = sk->sk_lingertime / HZ; 1026 break; 1027 1028 case SO_BSDCOMPAT: 1029 sock_warn_obsolete_bsdism("getsockopt"); 1030 break; 1031 1032 case SO_TIMESTAMP: 1033 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1034 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1035 break; 1036 1037 case SO_TIMESTAMPNS: 1038 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 1039 break; 1040 1041 case SO_TIMESTAMPING: 1042 v.val = 0; 1043 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE)) 1044 v.val |= SOF_TIMESTAMPING_TX_HARDWARE; 1045 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE)) 1046 v.val |= SOF_TIMESTAMPING_TX_SOFTWARE; 1047 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE)) 1048 v.val |= SOF_TIMESTAMPING_RX_HARDWARE; 1049 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE)) 1050 v.val |= SOF_TIMESTAMPING_RX_SOFTWARE; 1051 if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) 1052 v.val |= SOF_TIMESTAMPING_SOFTWARE; 1053 if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)) 1054 v.val |= SOF_TIMESTAMPING_SYS_HARDWARE; 1055 if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) 1056 v.val |= SOF_TIMESTAMPING_RAW_HARDWARE; 1057 break; 1058 1059 case SO_RCVTIMEO: 1060 lv = sizeof(struct timeval); 1061 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 1062 v.tm.tv_sec = 0; 1063 v.tm.tv_usec = 0; 1064 } else { 1065 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 1066 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 1067 } 1068 break; 1069 1070 case SO_SNDTIMEO: 1071 lv = sizeof(struct timeval); 1072 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 1073 v.tm.tv_sec = 0; 1074 v.tm.tv_usec = 0; 1075 } else { 1076 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1077 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1078 } 1079 break; 1080 1081 case SO_RCVLOWAT: 1082 v.val = sk->sk_rcvlowat; 1083 break; 1084 1085 case SO_SNDLOWAT: 1086 v.val = 1; 1087 break; 1088 1089 case SO_PASSCRED: 1090 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1091 break; 1092 1093 case SO_PEERCRED: 1094 { 1095 struct ucred peercred; 1096 if (len > sizeof(peercred)) 1097 len = sizeof(peercred); 1098 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1099 if (copy_to_user(optval, &peercred, len)) 1100 return -EFAULT; 1101 goto lenout; 1102 } 1103 1104 case SO_PEERNAME: 1105 { 1106 char address[128]; 1107 1108 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1109 return -ENOTCONN; 1110 if (lv < len) 1111 return -EINVAL; 1112 if (copy_to_user(optval, address, len)) 1113 return -EFAULT; 1114 goto lenout; 1115 } 1116 1117 /* Dubious BSD thing... Probably nobody even uses it, but 1118 * the UNIX standard wants it for whatever reason... -DaveM 1119 */ 1120 case SO_ACCEPTCONN: 1121 v.val = sk->sk_state == TCP_LISTEN; 1122 break; 1123 1124 case SO_PASSSEC: 1125 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1126 break; 1127 1128 case SO_PEERSEC: 1129 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1130 1131 case SO_MARK: 1132 v.val = sk->sk_mark; 1133 break; 1134 1135 case SO_RXQ_OVFL: 1136 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1137 break; 1138 1139 case SO_WIFI_STATUS: 1140 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1141 break; 1142 1143 case SO_PEEK_OFF: 1144 if (!sock->ops->set_peek_off) 1145 return -EOPNOTSUPP; 1146 1147 v.val = sk->sk_peek_off; 1148 break; 1149 case SO_NOFCS: 1150 v.val = sock_flag(sk, SOCK_NOFCS); 1151 break; 1152 1153 case SO_BINDTODEVICE: 1154 return sock_getbindtodevice(sk, optval, optlen, len); 1155 1156 case SO_GET_FILTER: 1157 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1158 if (len < 0) 1159 return len; 1160 1161 goto lenout; 1162 1163 case SO_LOCK_FILTER: 1164 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1165 break; 1166 1167 case SO_SELECT_ERR_QUEUE: 1168 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1169 break; 1170 1171 default: 1172 return -ENOPROTOOPT; 1173 } 1174 1175 if (len > lv) 1176 len = lv; 1177 if (copy_to_user(optval, &v, len)) 1178 return -EFAULT; 1179 lenout: 1180 if (put_user(len, optlen)) 1181 return -EFAULT; 1182 return 0; 1183 } 1184 1185 /* 1186 * Initialize an sk_lock. 1187 * 1188 * (We also register the sk_lock with the lock validator.) 1189 */ 1190 static inline void sock_lock_init(struct sock *sk) 1191 { 1192 sock_lock_init_class_and_name(sk, 1193 af_family_slock_key_strings[sk->sk_family], 1194 af_family_slock_keys + sk->sk_family, 1195 af_family_key_strings[sk->sk_family], 1196 af_family_keys + sk->sk_family); 1197 } 1198 1199 /* 1200 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1201 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1202 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1203 */ 1204 static void sock_copy(struct sock *nsk, const struct sock *osk) 1205 { 1206 #ifdef CONFIG_SECURITY_NETWORK 1207 void *sptr = nsk->sk_security; 1208 #endif 1209 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1210 1211 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1212 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1213 1214 #ifdef CONFIG_SECURITY_NETWORK 1215 nsk->sk_security = sptr; 1216 security_sk_clone(osk, nsk); 1217 #endif 1218 } 1219 1220 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size) 1221 { 1222 unsigned long nulls1, nulls2; 1223 1224 nulls1 = offsetof(struct sock, __sk_common.skc_node.next); 1225 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next); 1226 if (nulls1 > nulls2) 1227 swap(nulls1, nulls2); 1228 1229 if (nulls1 != 0) 1230 memset((char *)sk, 0, nulls1); 1231 memset((char *)sk + nulls1 + sizeof(void *), 0, 1232 nulls2 - nulls1 - sizeof(void *)); 1233 memset((char *)sk + nulls2 + sizeof(void *), 0, 1234 size - nulls2 - sizeof(void *)); 1235 } 1236 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls); 1237 1238 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1239 int family) 1240 { 1241 struct sock *sk; 1242 struct kmem_cache *slab; 1243 1244 slab = prot->slab; 1245 if (slab != NULL) { 1246 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1247 if (!sk) 1248 return sk; 1249 if (priority & __GFP_ZERO) { 1250 if (prot->clear_sk) 1251 prot->clear_sk(sk, prot->obj_size); 1252 else 1253 sk_prot_clear_nulls(sk, prot->obj_size); 1254 } 1255 } else 1256 sk = kmalloc(prot->obj_size, priority); 1257 1258 if (sk != NULL) { 1259 kmemcheck_annotate_bitfield(sk, flags); 1260 1261 if (security_sk_alloc(sk, family, priority)) 1262 goto out_free; 1263 1264 if (!try_module_get(prot->owner)) 1265 goto out_free_sec; 1266 sk_tx_queue_clear(sk); 1267 } 1268 1269 return sk; 1270 1271 out_free_sec: 1272 security_sk_free(sk); 1273 out_free: 1274 if (slab != NULL) 1275 kmem_cache_free(slab, sk); 1276 else 1277 kfree(sk); 1278 return NULL; 1279 } 1280 1281 static void sk_prot_free(struct proto *prot, struct sock *sk) 1282 { 1283 struct kmem_cache *slab; 1284 struct module *owner; 1285 1286 owner = prot->owner; 1287 slab = prot->slab; 1288 1289 security_sk_free(sk); 1290 if (slab != NULL) 1291 kmem_cache_free(slab, sk); 1292 else 1293 kfree(sk); 1294 module_put(owner); 1295 } 1296 1297 #if IS_ENABLED(CONFIG_NET_CLS_CGROUP) 1298 void sock_update_classid(struct sock *sk) 1299 { 1300 u32 classid; 1301 1302 classid = task_cls_classid(current); 1303 if (classid != sk->sk_classid) 1304 sk->sk_classid = classid; 1305 } 1306 EXPORT_SYMBOL(sock_update_classid); 1307 #endif 1308 1309 #if IS_ENABLED(CONFIG_NETPRIO_CGROUP) 1310 void sock_update_netprioidx(struct sock *sk) 1311 { 1312 if (in_interrupt()) 1313 return; 1314 1315 sk->sk_cgrp_prioidx = task_netprioidx(current); 1316 } 1317 EXPORT_SYMBOL_GPL(sock_update_netprioidx); 1318 #endif 1319 1320 /** 1321 * sk_alloc - All socket objects are allocated here 1322 * @net: the applicable net namespace 1323 * @family: protocol family 1324 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1325 * @prot: struct proto associated with this new sock instance 1326 */ 1327 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1328 struct proto *prot) 1329 { 1330 struct sock *sk; 1331 1332 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1333 if (sk) { 1334 sk->sk_family = family; 1335 /* 1336 * See comment in struct sock definition to understand 1337 * why we need sk_prot_creator -acme 1338 */ 1339 sk->sk_prot = sk->sk_prot_creator = prot; 1340 sock_lock_init(sk); 1341 sock_net_set(sk, get_net(net)); 1342 atomic_set(&sk->sk_wmem_alloc, 1); 1343 1344 sock_update_classid(sk); 1345 sock_update_netprioidx(sk); 1346 } 1347 1348 return sk; 1349 } 1350 EXPORT_SYMBOL(sk_alloc); 1351 1352 static void __sk_free(struct sock *sk) 1353 { 1354 struct sk_filter *filter; 1355 1356 if (sk->sk_destruct) 1357 sk->sk_destruct(sk); 1358 1359 filter = rcu_dereference_check(sk->sk_filter, 1360 atomic_read(&sk->sk_wmem_alloc) == 0); 1361 if (filter) { 1362 sk_filter_uncharge(sk, filter); 1363 RCU_INIT_POINTER(sk->sk_filter, NULL); 1364 } 1365 1366 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1367 1368 if (atomic_read(&sk->sk_omem_alloc)) 1369 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1370 __func__, atomic_read(&sk->sk_omem_alloc)); 1371 1372 if (sk->sk_peer_cred) 1373 put_cred(sk->sk_peer_cred); 1374 put_pid(sk->sk_peer_pid); 1375 put_net(sock_net(sk)); 1376 sk_prot_free(sk->sk_prot_creator, sk); 1377 } 1378 1379 void sk_free(struct sock *sk) 1380 { 1381 /* 1382 * We subtract one from sk_wmem_alloc and can know if 1383 * some packets are still in some tx queue. 1384 * If not null, sock_wfree() will call __sk_free(sk) later 1385 */ 1386 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1387 __sk_free(sk); 1388 } 1389 EXPORT_SYMBOL(sk_free); 1390 1391 /* 1392 * Last sock_put should drop reference to sk->sk_net. It has already 1393 * been dropped in sk_change_net. Taking reference to stopping namespace 1394 * is not an option. 1395 * Take reference to a socket to remove it from hash _alive_ and after that 1396 * destroy it in the context of init_net. 1397 */ 1398 void sk_release_kernel(struct sock *sk) 1399 { 1400 if (sk == NULL || sk->sk_socket == NULL) 1401 return; 1402 1403 sock_hold(sk); 1404 sock_release(sk->sk_socket); 1405 release_net(sock_net(sk)); 1406 sock_net_set(sk, get_net(&init_net)); 1407 sock_put(sk); 1408 } 1409 EXPORT_SYMBOL(sk_release_kernel); 1410 1411 static void sk_update_clone(const struct sock *sk, struct sock *newsk) 1412 { 1413 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1414 sock_update_memcg(newsk); 1415 } 1416 1417 /** 1418 * sk_clone_lock - clone a socket, and lock its clone 1419 * @sk: the socket to clone 1420 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1421 * 1422 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1423 */ 1424 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1425 { 1426 struct sock *newsk; 1427 1428 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1429 if (newsk != NULL) { 1430 struct sk_filter *filter; 1431 1432 sock_copy(newsk, sk); 1433 1434 /* SANITY */ 1435 get_net(sock_net(newsk)); 1436 sk_node_init(&newsk->sk_node); 1437 sock_lock_init(newsk); 1438 bh_lock_sock(newsk); 1439 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1440 newsk->sk_backlog.len = 0; 1441 1442 atomic_set(&newsk->sk_rmem_alloc, 0); 1443 /* 1444 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1445 */ 1446 atomic_set(&newsk->sk_wmem_alloc, 1); 1447 atomic_set(&newsk->sk_omem_alloc, 0); 1448 skb_queue_head_init(&newsk->sk_receive_queue); 1449 skb_queue_head_init(&newsk->sk_write_queue); 1450 #ifdef CONFIG_NET_DMA 1451 skb_queue_head_init(&newsk->sk_async_wait_queue); 1452 #endif 1453 1454 spin_lock_init(&newsk->sk_dst_lock); 1455 rwlock_init(&newsk->sk_callback_lock); 1456 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1457 af_callback_keys + newsk->sk_family, 1458 af_family_clock_key_strings[newsk->sk_family]); 1459 1460 newsk->sk_dst_cache = NULL; 1461 newsk->sk_wmem_queued = 0; 1462 newsk->sk_forward_alloc = 0; 1463 newsk->sk_send_head = NULL; 1464 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1465 1466 sock_reset_flag(newsk, SOCK_DONE); 1467 skb_queue_head_init(&newsk->sk_error_queue); 1468 1469 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1470 if (filter != NULL) 1471 sk_filter_charge(newsk, filter); 1472 1473 if (unlikely(xfrm_sk_clone_policy(newsk))) { 1474 /* It is still raw copy of parent, so invalidate 1475 * destructor and make plain sk_free() */ 1476 newsk->sk_destruct = NULL; 1477 bh_unlock_sock(newsk); 1478 sk_free(newsk); 1479 newsk = NULL; 1480 goto out; 1481 } 1482 1483 newsk->sk_err = 0; 1484 newsk->sk_priority = 0; 1485 /* 1486 * Before updating sk_refcnt, we must commit prior changes to memory 1487 * (Documentation/RCU/rculist_nulls.txt for details) 1488 */ 1489 smp_wmb(); 1490 atomic_set(&newsk->sk_refcnt, 2); 1491 1492 /* 1493 * Increment the counter in the same struct proto as the master 1494 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1495 * is the same as sk->sk_prot->socks, as this field was copied 1496 * with memcpy). 1497 * 1498 * This _changes_ the previous behaviour, where 1499 * tcp_create_openreq_child always was incrementing the 1500 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1501 * to be taken into account in all callers. -acme 1502 */ 1503 sk_refcnt_debug_inc(newsk); 1504 sk_set_socket(newsk, NULL); 1505 newsk->sk_wq = NULL; 1506 1507 sk_update_clone(sk, newsk); 1508 1509 if (newsk->sk_prot->sockets_allocated) 1510 sk_sockets_allocated_inc(newsk); 1511 1512 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1513 net_enable_timestamp(); 1514 } 1515 out: 1516 return newsk; 1517 } 1518 EXPORT_SYMBOL_GPL(sk_clone_lock); 1519 1520 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1521 { 1522 __sk_dst_set(sk, dst); 1523 sk->sk_route_caps = dst->dev->features; 1524 if (sk->sk_route_caps & NETIF_F_GSO) 1525 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1526 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1527 if (sk_can_gso(sk)) { 1528 if (dst->header_len) { 1529 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1530 } else { 1531 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1532 sk->sk_gso_max_size = dst->dev->gso_max_size; 1533 sk->sk_gso_max_segs = dst->dev->gso_max_segs; 1534 } 1535 } 1536 } 1537 EXPORT_SYMBOL_GPL(sk_setup_caps); 1538 1539 /* 1540 * Simple resource managers for sockets. 1541 */ 1542 1543 1544 /* 1545 * Write buffer destructor automatically called from kfree_skb. 1546 */ 1547 void sock_wfree(struct sk_buff *skb) 1548 { 1549 struct sock *sk = skb->sk; 1550 unsigned int len = skb->truesize; 1551 1552 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1553 /* 1554 * Keep a reference on sk_wmem_alloc, this will be released 1555 * after sk_write_space() call 1556 */ 1557 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1558 sk->sk_write_space(sk); 1559 len = 1; 1560 } 1561 /* 1562 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1563 * could not do because of in-flight packets 1564 */ 1565 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1566 __sk_free(sk); 1567 } 1568 EXPORT_SYMBOL(sock_wfree); 1569 1570 /* 1571 * Read buffer destructor automatically called from kfree_skb. 1572 */ 1573 void sock_rfree(struct sk_buff *skb) 1574 { 1575 struct sock *sk = skb->sk; 1576 unsigned int len = skb->truesize; 1577 1578 atomic_sub(len, &sk->sk_rmem_alloc); 1579 sk_mem_uncharge(sk, len); 1580 } 1581 EXPORT_SYMBOL(sock_rfree); 1582 1583 void sock_edemux(struct sk_buff *skb) 1584 { 1585 struct sock *sk = skb->sk; 1586 1587 #ifdef CONFIG_INET 1588 if (sk->sk_state == TCP_TIME_WAIT) 1589 inet_twsk_put(inet_twsk(sk)); 1590 else 1591 #endif 1592 sock_put(sk); 1593 } 1594 EXPORT_SYMBOL(sock_edemux); 1595 1596 kuid_t sock_i_uid(struct sock *sk) 1597 { 1598 kuid_t uid; 1599 1600 read_lock_bh(&sk->sk_callback_lock); 1601 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1602 read_unlock_bh(&sk->sk_callback_lock); 1603 return uid; 1604 } 1605 EXPORT_SYMBOL(sock_i_uid); 1606 1607 unsigned long sock_i_ino(struct sock *sk) 1608 { 1609 unsigned long ino; 1610 1611 read_lock_bh(&sk->sk_callback_lock); 1612 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1613 read_unlock_bh(&sk->sk_callback_lock); 1614 return ino; 1615 } 1616 EXPORT_SYMBOL(sock_i_ino); 1617 1618 /* 1619 * Allocate a skb from the socket's send buffer. 1620 */ 1621 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1622 gfp_t priority) 1623 { 1624 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1625 struct sk_buff *skb = alloc_skb(size, priority); 1626 if (skb) { 1627 skb_set_owner_w(skb, sk); 1628 return skb; 1629 } 1630 } 1631 return NULL; 1632 } 1633 EXPORT_SYMBOL(sock_wmalloc); 1634 1635 /* 1636 * Allocate a skb from the socket's receive buffer. 1637 */ 1638 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force, 1639 gfp_t priority) 1640 { 1641 if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) { 1642 struct sk_buff *skb = alloc_skb(size, priority); 1643 if (skb) { 1644 skb_set_owner_r(skb, sk); 1645 return skb; 1646 } 1647 } 1648 return NULL; 1649 } 1650 1651 /* 1652 * Allocate a memory block from the socket's option memory buffer. 1653 */ 1654 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1655 { 1656 if ((unsigned int)size <= sysctl_optmem_max && 1657 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1658 void *mem; 1659 /* First do the add, to avoid the race if kmalloc 1660 * might sleep. 1661 */ 1662 atomic_add(size, &sk->sk_omem_alloc); 1663 mem = kmalloc(size, priority); 1664 if (mem) 1665 return mem; 1666 atomic_sub(size, &sk->sk_omem_alloc); 1667 } 1668 return NULL; 1669 } 1670 EXPORT_SYMBOL(sock_kmalloc); 1671 1672 /* 1673 * Free an option memory block. 1674 */ 1675 void sock_kfree_s(struct sock *sk, void *mem, int size) 1676 { 1677 kfree(mem); 1678 atomic_sub(size, &sk->sk_omem_alloc); 1679 } 1680 EXPORT_SYMBOL(sock_kfree_s); 1681 1682 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1683 I think, these locks should be removed for datagram sockets. 1684 */ 1685 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1686 { 1687 DEFINE_WAIT(wait); 1688 1689 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1690 for (;;) { 1691 if (!timeo) 1692 break; 1693 if (signal_pending(current)) 1694 break; 1695 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1696 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1697 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1698 break; 1699 if (sk->sk_shutdown & SEND_SHUTDOWN) 1700 break; 1701 if (sk->sk_err) 1702 break; 1703 timeo = schedule_timeout(timeo); 1704 } 1705 finish_wait(sk_sleep(sk), &wait); 1706 return timeo; 1707 } 1708 1709 1710 /* 1711 * Generic send/receive buffer handlers 1712 */ 1713 1714 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1715 unsigned long data_len, int noblock, 1716 int *errcode) 1717 { 1718 struct sk_buff *skb; 1719 gfp_t gfp_mask; 1720 long timeo; 1721 int err; 1722 int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT; 1723 1724 err = -EMSGSIZE; 1725 if (npages > MAX_SKB_FRAGS) 1726 goto failure; 1727 1728 gfp_mask = sk->sk_allocation; 1729 if (gfp_mask & __GFP_WAIT) 1730 gfp_mask |= __GFP_REPEAT; 1731 1732 timeo = sock_sndtimeo(sk, noblock); 1733 while (1) { 1734 err = sock_error(sk); 1735 if (err != 0) 1736 goto failure; 1737 1738 err = -EPIPE; 1739 if (sk->sk_shutdown & SEND_SHUTDOWN) 1740 goto failure; 1741 1742 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1743 skb = alloc_skb(header_len, gfp_mask); 1744 if (skb) { 1745 int i; 1746 1747 /* No pages, we're done... */ 1748 if (!data_len) 1749 break; 1750 1751 skb->truesize += data_len; 1752 skb_shinfo(skb)->nr_frags = npages; 1753 for (i = 0; i < npages; i++) { 1754 struct page *page; 1755 1756 page = alloc_pages(sk->sk_allocation, 0); 1757 if (!page) { 1758 err = -ENOBUFS; 1759 skb_shinfo(skb)->nr_frags = i; 1760 kfree_skb(skb); 1761 goto failure; 1762 } 1763 1764 __skb_fill_page_desc(skb, i, 1765 page, 0, 1766 (data_len >= PAGE_SIZE ? 1767 PAGE_SIZE : 1768 data_len)); 1769 data_len -= PAGE_SIZE; 1770 } 1771 1772 /* Full success... */ 1773 break; 1774 } 1775 err = -ENOBUFS; 1776 goto failure; 1777 } 1778 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1779 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1780 err = -EAGAIN; 1781 if (!timeo) 1782 goto failure; 1783 if (signal_pending(current)) 1784 goto interrupted; 1785 timeo = sock_wait_for_wmem(sk, timeo); 1786 } 1787 1788 skb_set_owner_w(skb, sk); 1789 return skb; 1790 1791 interrupted: 1792 err = sock_intr_errno(timeo); 1793 failure: 1794 *errcode = err; 1795 return NULL; 1796 } 1797 EXPORT_SYMBOL(sock_alloc_send_pskb); 1798 1799 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1800 int noblock, int *errcode) 1801 { 1802 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode); 1803 } 1804 EXPORT_SYMBOL(sock_alloc_send_skb); 1805 1806 /* On 32bit arches, an skb frag is limited to 2^15 */ 1807 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1808 1809 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 1810 { 1811 int order; 1812 1813 if (pfrag->page) { 1814 if (atomic_read(&pfrag->page->_count) == 1) { 1815 pfrag->offset = 0; 1816 return true; 1817 } 1818 if (pfrag->offset < pfrag->size) 1819 return true; 1820 put_page(pfrag->page); 1821 } 1822 1823 /* We restrict high order allocations to users that can afford to wait */ 1824 order = (sk->sk_allocation & __GFP_WAIT) ? SKB_FRAG_PAGE_ORDER : 0; 1825 1826 do { 1827 gfp_t gfp = sk->sk_allocation; 1828 1829 if (order) 1830 gfp |= __GFP_COMP | __GFP_NOWARN; 1831 pfrag->page = alloc_pages(gfp, order); 1832 if (likely(pfrag->page)) { 1833 pfrag->offset = 0; 1834 pfrag->size = PAGE_SIZE << order; 1835 return true; 1836 } 1837 } while (--order >= 0); 1838 1839 sk_enter_memory_pressure(sk); 1840 sk_stream_moderate_sndbuf(sk); 1841 return false; 1842 } 1843 EXPORT_SYMBOL(sk_page_frag_refill); 1844 1845 static void __lock_sock(struct sock *sk) 1846 __releases(&sk->sk_lock.slock) 1847 __acquires(&sk->sk_lock.slock) 1848 { 1849 DEFINE_WAIT(wait); 1850 1851 for (;;) { 1852 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 1853 TASK_UNINTERRUPTIBLE); 1854 spin_unlock_bh(&sk->sk_lock.slock); 1855 schedule(); 1856 spin_lock_bh(&sk->sk_lock.slock); 1857 if (!sock_owned_by_user(sk)) 1858 break; 1859 } 1860 finish_wait(&sk->sk_lock.wq, &wait); 1861 } 1862 1863 static void __release_sock(struct sock *sk) 1864 __releases(&sk->sk_lock.slock) 1865 __acquires(&sk->sk_lock.slock) 1866 { 1867 struct sk_buff *skb = sk->sk_backlog.head; 1868 1869 do { 1870 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 1871 bh_unlock_sock(sk); 1872 1873 do { 1874 struct sk_buff *next = skb->next; 1875 1876 prefetch(next); 1877 WARN_ON_ONCE(skb_dst_is_noref(skb)); 1878 skb->next = NULL; 1879 sk_backlog_rcv(sk, skb); 1880 1881 /* 1882 * We are in process context here with softirqs 1883 * disabled, use cond_resched_softirq() to preempt. 1884 * This is safe to do because we've taken the backlog 1885 * queue private: 1886 */ 1887 cond_resched_softirq(); 1888 1889 skb = next; 1890 } while (skb != NULL); 1891 1892 bh_lock_sock(sk); 1893 } while ((skb = sk->sk_backlog.head) != NULL); 1894 1895 /* 1896 * Doing the zeroing here guarantee we can not loop forever 1897 * while a wild producer attempts to flood us. 1898 */ 1899 sk->sk_backlog.len = 0; 1900 } 1901 1902 /** 1903 * sk_wait_data - wait for data to arrive at sk_receive_queue 1904 * @sk: sock to wait on 1905 * @timeo: for how long 1906 * 1907 * Now socket state including sk->sk_err is changed only under lock, 1908 * hence we may omit checks after joining wait queue. 1909 * We check receive queue before schedule() only as optimization; 1910 * it is very likely that release_sock() added new data. 1911 */ 1912 int sk_wait_data(struct sock *sk, long *timeo) 1913 { 1914 int rc; 1915 DEFINE_WAIT(wait); 1916 1917 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1918 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1919 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); 1920 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1921 finish_wait(sk_sleep(sk), &wait); 1922 return rc; 1923 } 1924 EXPORT_SYMBOL(sk_wait_data); 1925 1926 /** 1927 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 1928 * @sk: socket 1929 * @size: memory size to allocate 1930 * @kind: allocation type 1931 * 1932 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 1933 * rmem allocation. This function assumes that protocols which have 1934 * memory_pressure use sk_wmem_queued as write buffer accounting. 1935 */ 1936 int __sk_mem_schedule(struct sock *sk, int size, int kind) 1937 { 1938 struct proto *prot = sk->sk_prot; 1939 int amt = sk_mem_pages(size); 1940 long allocated; 1941 int parent_status = UNDER_LIMIT; 1942 1943 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; 1944 1945 allocated = sk_memory_allocated_add(sk, amt, &parent_status); 1946 1947 /* Under limit. */ 1948 if (parent_status == UNDER_LIMIT && 1949 allocated <= sk_prot_mem_limits(sk, 0)) { 1950 sk_leave_memory_pressure(sk); 1951 return 1; 1952 } 1953 1954 /* Under pressure. (we or our parents) */ 1955 if ((parent_status > SOFT_LIMIT) || 1956 allocated > sk_prot_mem_limits(sk, 1)) 1957 sk_enter_memory_pressure(sk); 1958 1959 /* Over hard limit (we or our parents) */ 1960 if ((parent_status == OVER_LIMIT) || 1961 (allocated > sk_prot_mem_limits(sk, 2))) 1962 goto suppress_allocation; 1963 1964 /* guarantee minimum buffer size under pressure */ 1965 if (kind == SK_MEM_RECV) { 1966 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 1967 return 1; 1968 1969 } else { /* SK_MEM_SEND */ 1970 if (sk->sk_type == SOCK_STREAM) { 1971 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 1972 return 1; 1973 } else if (atomic_read(&sk->sk_wmem_alloc) < 1974 prot->sysctl_wmem[0]) 1975 return 1; 1976 } 1977 1978 if (sk_has_memory_pressure(sk)) { 1979 int alloc; 1980 1981 if (!sk_under_memory_pressure(sk)) 1982 return 1; 1983 alloc = sk_sockets_allocated_read_positive(sk); 1984 if (sk_prot_mem_limits(sk, 2) > alloc * 1985 sk_mem_pages(sk->sk_wmem_queued + 1986 atomic_read(&sk->sk_rmem_alloc) + 1987 sk->sk_forward_alloc)) 1988 return 1; 1989 } 1990 1991 suppress_allocation: 1992 1993 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 1994 sk_stream_moderate_sndbuf(sk); 1995 1996 /* Fail only if socket is _under_ its sndbuf. 1997 * In this case we cannot block, so that we have to fail. 1998 */ 1999 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2000 return 1; 2001 } 2002 2003 trace_sock_exceed_buf_limit(sk, prot, allocated); 2004 2005 /* Alas. Undo changes. */ 2006 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM; 2007 2008 sk_memory_allocated_sub(sk, amt); 2009 2010 return 0; 2011 } 2012 EXPORT_SYMBOL(__sk_mem_schedule); 2013 2014 /** 2015 * __sk_reclaim - reclaim memory_allocated 2016 * @sk: socket 2017 */ 2018 void __sk_mem_reclaim(struct sock *sk) 2019 { 2020 sk_memory_allocated_sub(sk, 2021 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT); 2022 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1; 2023 2024 if (sk_under_memory_pressure(sk) && 2025 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2026 sk_leave_memory_pressure(sk); 2027 } 2028 EXPORT_SYMBOL(__sk_mem_reclaim); 2029 2030 2031 /* 2032 * Set of default routines for initialising struct proto_ops when 2033 * the protocol does not support a particular function. In certain 2034 * cases where it makes no sense for a protocol to have a "do nothing" 2035 * function, some default processing is provided. 2036 */ 2037 2038 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2039 { 2040 return -EOPNOTSUPP; 2041 } 2042 EXPORT_SYMBOL(sock_no_bind); 2043 2044 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2045 int len, int flags) 2046 { 2047 return -EOPNOTSUPP; 2048 } 2049 EXPORT_SYMBOL(sock_no_connect); 2050 2051 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2052 { 2053 return -EOPNOTSUPP; 2054 } 2055 EXPORT_SYMBOL(sock_no_socketpair); 2056 2057 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 2058 { 2059 return -EOPNOTSUPP; 2060 } 2061 EXPORT_SYMBOL(sock_no_accept); 2062 2063 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2064 int *len, int peer) 2065 { 2066 return -EOPNOTSUPP; 2067 } 2068 EXPORT_SYMBOL(sock_no_getname); 2069 2070 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 2071 { 2072 return 0; 2073 } 2074 EXPORT_SYMBOL(sock_no_poll); 2075 2076 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2077 { 2078 return -EOPNOTSUPP; 2079 } 2080 EXPORT_SYMBOL(sock_no_ioctl); 2081 2082 int sock_no_listen(struct socket *sock, int backlog) 2083 { 2084 return -EOPNOTSUPP; 2085 } 2086 EXPORT_SYMBOL(sock_no_listen); 2087 2088 int sock_no_shutdown(struct socket *sock, int how) 2089 { 2090 return -EOPNOTSUPP; 2091 } 2092 EXPORT_SYMBOL(sock_no_shutdown); 2093 2094 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2095 char __user *optval, unsigned int optlen) 2096 { 2097 return -EOPNOTSUPP; 2098 } 2099 EXPORT_SYMBOL(sock_no_setsockopt); 2100 2101 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2102 char __user *optval, int __user *optlen) 2103 { 2104 return -EOPNOTSUPP; 2105 } 2106 EXPORT_SYMBOL(sock_no_getsockopt); 2107 2108 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2109 size_t len) 2110 { 2111 return -EOPNOTSUPP; 2112 } 2113 EXPORT_SYMBOL(sock_no_sendmsg); 2114 2115 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2116 size_t len, int flags) 2117 { 2118 return -EOPNOTSUPP; 2119 } 2120 EXPORT_SYMBOL(sock_no_recvmsg); 2121 2122 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2123 { 2124 /* Mirror missing mmap method error code */ 2125 return -ENODEV; 2126 } 2127 EXPORT_SYMBOL(sock_no_mmap); 2128 2129 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2130 { 2131 ssize_t res; 2132 struct msghdr msg = {.msg_flags = flags}; 2133 struct kvec iov; 2134 char *kaddr = kmap(page); 2135 iov.iov_base = kaddr + offset; 2136 iov.iov_len = size; 2137 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2138 kunmap(page); 2139 return res; 2140 } 2141 EXPORT_SYMBOL(sock_no_sendpage); 2142 2143 /* 2144 * Default Socket Callbacks 2145 */ 2146 2147 static void sock_def_wakeup(struct sock *sk) 2148 { 2149 struct socket_wq *wq; 2150 2151 rcu_read_lock(); 2152 wq = rcu_dereference(sk->sk_wq); 2153 if (wq_has_sleeper(wq)) 2154 wake_up_interruptible_all(&wq->wait); 2155 rcu_read_unlock(); 2156 } 2157 2158 static void sock_def_error_report(struct sock *sk) 2159 { 2160 struct socket_wq *wq; 2161 2162 rcu_read_lock(); 2163 wq = rcu_dereference(sk->sk_wq); 2164 if (wq_has_sleeper(wq)) 2165 wake_up_interruptible_poll(&wq->wait, POLLERR); 2166 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2167 rcu_read_unlock(); 2168 } 2169 2170 static void sock_def_readable(struct sock *sk, int len) 2171 { 2172 struct socket_wq *wq; 2173 2174 rcu_read_lock(); 2175 wq = rcu_dereference(sk->sk_wq); 2176 if (wq_has_sleeper(wq)) 2177 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI | 2178 POLLRDNORM | POLLRDBAND); 2179 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2180 rcu_read_unlock(); 2181 } 2182 2183 static void sock_def_write_space(struct sock *sk) 2184 { 2185 struct socket_wq *wq; 2186 2187 rcu_read_lock(); 2188 2189 /* Do not wake up a writer until he can make "significant" 2190 * progress. --DaveM 2191 */ 2192 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2193 wq = rcu_dereference(sk->sk_wq); 2194 if (wq_has_sleeper(wq)) 2195 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 2196 POLLWRNORM | POLLWRBAND); 2197 2198 /* Should agree with poll, otherwise some programs break */ 2199 if (sock_writeable(sk)) 2200 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2201 } 2202 2203 rcu_read_unlock(); 2204 } 2205 2206 static void sock_def_destruct(struct sock *sk) 2207 { 2208 kfree(sk->sk_protinfo); 2209 } 2210 2211 void sk_send_sigurg(struct sock *sk) 2212 { 2213 if (sk->sk_socket && sk->sk_socket->file) 2214 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2215 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2216 } 2217 EXPORT_SYMBOL(sk_send_sigurg); 2218 2219 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2220 unsigned long expires) 2221 { 2222 if (!mod_timer(timer, expires)) 2223 sock_hold(sk); 2224 } 2225 EXPORT_SYMBOL(sk_reset_timer); 2226 2227 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2228 { 2229 if (del_timer(timer)) 2230 __sock_put(sk); 2231 } 2232 EXPORT_SYMBOL(sk_stop_timer); 2233 2234 void sock_init_data(struct socket *sock, struct sock *sk) 2235 { 2236 skb_queue_head_init(&sk->sk_receive_queue); 2237 skb_queue_head_init(&sk->sk_write_queue); 2238 skb_queue_head_init(&sk->sk_error_queue); 2239 #ifdef CONFIG_NET_DMA 2240 skb_queue_head_init(&sk->sk_async_wait_queue); 2241 #endif 2242 2243 sk->sk_send_head = NULL; 2244 2245 init_timer(&sk->sk_timer); 2246 2247 sk->sk_allocation = GFP_KERNEL; 2248 sk->sk_rcvbuf = sysctl_rmem_default; 2249 sk->sk_sndbuf = sysctl_wmem_default; 2250 sk->sk_state = TCP_CLOSE; 2251 sk_set_socket(sk, sock); 2252 2253 sock_set_flag(sk, SOCK_ZAPPED); 2254 2255 if (sock) { 2256 sk->sk_type = sock->type; 2257 sk->sk_wq = sock->wq; 2258 sock->sk = sk; 2259 } else 2260 sk->sk_wq = NULL; 2261 2262 spin_lock_init(&sk->sk_dst_lock); 2263 rwlock_init(&sk->sk_callback_lock); 2264 lockdep_set_class_and_name(&sk->sk_callback_lock, 2265 af_callback_keys + sk->sk_family, 2266 af_family_clock_key_strings[sk->sk_family]); 2267 2268 sk->sk_state_change = sock_def_wakeup; 2269 sk->sk_data_ready = sock_def_readable; 2270 sk->sk_write_space = sock_def_write_space; 2271 sk->sk_error_report = sock_def_error_report; 2272 sk->sk_destruct = sock_def_destruct; 2273 2274 sk->sk_frag.page = NULL; 2275 sk->sk_frag.offset = 0; 2276 sk->sk_peek_off = -1; 2277 2278 sk->sk_peer_pid = NULL; 2279 sk->sk_peer_cred = NULL; 2280 sk->sk_write_pending = 0; 2281 sk->sk_rcvlowat = 1; 2282 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2283 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2284 2285 sk->sk_stamp = ktime_set(-1L, 0); 2286 2287 /* 2288 * Before updating sk_refcnt, we must commit prior changes to memory 2289 * (Documentation/RCU/rculist_nulls.txt for details) 2290 */ 2291 smp_wmb(); 2292 atomic_set(&sk->sk_refcnt, 1); 2293 atomic_set(&sk->sk_drops, 0); 2294 } 2295 EXPORT_SYMBOL(sock_init_data); 2296 2297 void lock_sock_nested(struct sock *sk, int subclass) 2298 { 2299 might_sleep(); 2300 spin_lock_bh(&sk->sk_lock.slock); 2301 if (sk->sk_lock.owned) 2302 __lock_sock(sk); 2303 sk->sk_lock.owned = 1; 2304 spin_unlock(&sk->sk_lock.slock); 2305 /* 2306 * The sk_lock has mutex_lock() semantics here: 2307 */ 2308 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2309 local_bh_enable(); 2310 } 2311 EXPORT_SYMBOL(lock_sock_nested); 2312 2313 void release_sock(struct sock *sk) 2314 { 2315 /* 2316 * The sk_lock has mutex_unlock() semantics: 2317 */ 2318 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 2319 2320 spin_lock_bh(&sk->sk_lock.slock); 2321 if (sk->sk_backlog.tail) 2322 __release_sock(sk); 2323 2324 if (sk->sk_prot->release_cb) 2325 sk->sk_prot->release_cb(sk); 2326 2327 sk->sk_lock.owned = 0; 2328 if (waitqueue_active(&sk->sk_lock.wq)) 2329 wake_up(&sk->sk_lock.wq); 2330 spin_unlock_bh(&sk->sk_lock.slock); 2331 } 2332 EXPORT_SYMBOL(release_sock); 2333 2334 /** 2335 * lock_sock_fast - fast version of lock_sock 2336 * @sk: socket 2337 * 2338 * This version should be used for very small section, where process wont block 2339 * return false if fast path is taken 2340 * sk_lock.slock locked, owned = 0, BH disabled 2341 * return true if slow path is taken 2342 * sk_lock.slock unlocked, owned = 1, BH enabled 2343 */ 2344 bool lock_sock_fast(struct sock *sk) 2345 { 2346 might_sleep(); 2347 spin_lock_bh(&sk->sk_lock.slock); 2348 2349 if (!sk->sk_lock.owned) 2350 /* 2351 * Note : We must disable BH 2352 */ 2353 return false; 2354 2355 __lock_sock(sk); 2356 sk->sk_lock.owned = 1; 2357 spin_unlock(&sk->sk_lock.slock); 2358 /* 2359 * The sk_lock has mutex_lock() semantics here: 2360 */ 2361 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2362 local_bh_enable(); 2363 return true; 2364 } 2365 EXPORT_SYMBOL(lock_sock_fast); 2366 2367 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2368 { 2369 struct timeval tv; 2370 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2371 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2372 tv = ktime_to_timeval(sk->sk_stamp); 2373 if (tv.tv_sec == -1) 2374 return -ENOENT; 2375 if (tv.tv_sec == 0) { 2376 sk->sk_stamp = ktime_get_real(); 2377 tv = ktime_to_timeval(sk->sk_stamp); 2378 } 2379 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2380 } 2381 EXPORT_SYMBOL(sock_get_timestamp); 2382 2383 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2384 { 2385 struct timespec ts; 2386 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2387 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2388 ts = ktime_to_timespec(sk->sk_stamp); 2389 if (ts.tv_sec == -1) 2390 return -ENOENT; 2391 if (ts.tv_sec == 0) { 2392 sk->sk_stamp = ktime_get_real(); 2393 ts = ktime_to_timespec(sk->sk_stamp); 2394 } 2395 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2396 } 2397 EXPORT_SYMBOL(sock_get_timestampns); 2398 2399 void sock_enable_timestamp(struct sock *sk, int flag) 2400 { 2401 if (!sock_flag(sk, flag)) { 2402 unsigned long previous_flags = sk->sk_flags; 2403 2404 sock_set_flag(sk, flag); 2405 /* 2406 * we just set one of the two flags which require net 2407 * time stamping, but time stamping might have been on 2408 * already because of the other one 2409 */ 2410 if (!(previous_flags & SK_FLAGS_TIMESTAMP)) 2411 net_enable_timestamp(); 2412 } 2413 } 2414 2415 /* 2416 * Get a socket option on an socket. 2417 * 2418 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2419 * asynchronous errors should be reported by getsockopt. We assume 2420 * this means if you specify SO_ERROR (otherwise whats the point of it). 2421 */ 2422 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2423 char __user *optval, int __user *optlen) 2424 { 2425 struct sock *sk = sock->sk; 2426 2427 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2428 } 2429 EXPORT_SYMBOL(sock_common_getsockopt); 2430 2431 #ifdef CONFIG_COMPAT 2432 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2433 char __user *optval, int __user *optlen) 2434 { 2435 struct sock *sk = sock->sk; 2436 2437 if (sk->sk_prot->compat_getsockopt != NULL) 2438 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2439 optval, optlen); 2440 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2441 } 2442 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2443 #endif 2444 2445 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, 2446 struct msghdr *msg, size_t size, int flags) 2447 { 2448 struct sock *sk = sock->sk; 2449 int addr_len = 0; 2450 int err; 2451 2452 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT, 2453 flags & ~MSG_DONTWAIT, &addr_len); 2454 if (err >= 0) 2455 msg->msg_namelen = addr_len; 2456 return err; 2457 } 2458 EXPORT_SYMBOL(sock_common_recvmsg); 2459 2460 /* 2461 * Set socket options on an inet socket. 2462 */ 2463 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2464 char __user *optval, unsigned int optlen) 2465 { 2466 struct sock *sk = sock->sk; 2467 2468 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2469 } 2470 EXPORT_SYMBOL(sock_common_setsockopt); 2471 2472 #ifdef CONFIG_COMPAT 2473 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2474 char __user *optval, unsigned int optlen) 2475 { 2476 struct sock *sk = sock->sk; 2477 2478 if (sk->sk_prot->compat_setsockopt != NULL) 2479 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2480 optval, optlen); 2481 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2482 } 2483 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2484 #endif 2485 2486 void sk_common_release(struct sock *sk) 2487 { 2488 if (sk->sk_prot->destroy) 2489 sk->sk_prot->destroy(sk); 2490 2491 /* 2492 * Observation: when sock_common_release is called, processes have 2493 * no access to socket. But net still has. 2494 * Step one, detach it from networking: 2495 * 2496 * A. Remove from hash tables. 2497 */ 2498 2499 sk->sk_prot->unhash(sk); 2500 2501 /* 2502 * In this point socket cannot receive new packets, but it is possible 2503 * that some packets are in flight because some CPU runs receiver and 2504 * did hash table lookup before we unhashed socket. They will achieve 2505 * receive queue and will be purged by socket destructor. 2506 * 2507 * Also we still have packets pending on receive queue and probably, 2508 * our own packets waiting in device queues. sock_destroy will drain 2509 * receive queue, but transmitted packets will delay socket destruction 2510 * until the last reference will be released. 2511 */ 2512 2513 sock_orphan(sk); 2514 2515 xfrm_sk_free_policy(sk); 2516 2517 sk_refcnt_debug_release(sk); 2518 2519 if (sk->sk_frag.page) { 2520 put_page(sk->sk_frag.page); 2521 sk->sk_frag.page = NULL; 2522 } 2523 2524 sock_put(sk); 2525 } 2526 EXPORT_SYMBOL(sk_common_release); 2527 2528 #ifdef CONFIG_PROC_FS 2529 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2530 struct prot_inuse { 2531 int val[PROTO_INUSE_NR]; 2532 }; 2533 2534 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2535 2536 #ifdef CONFIG_NET_NS 2537 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2538 { 2539 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2540 } 2541 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2542 2543 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2544 { 2545 int cpu, idx = prot->inuse_idx; 2546 int res = 0; 2547 2548 for_each_possible_cpu(cpu) 2549 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2550 2551 return res >= 0 ? res : 0; 2552 } 2553 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2554 2555 static int __net_init sock_inuse_init_net(struct net *net) 2556 { 2557 net->core.inuse = alloc_percpu(struct prot_inuse); 2558 return net->core.inuse ? 0 : -ENOMEM; 2559 } 2560 2561 static void __net_exit sock_inuse_exit_net(struct net *net) 2562 { 2563 free_percpu(net->core.inuse); 2564 } 2565 2566 static struct pernet_operations net_inuse_ops = { 2567 .init = sock_inuse_init_net, 2568 .exit = sock_inuse_exit_net, 2569 }; 2570 2571 static __init int net_inuse_init(void) 2572 { 2573 if (register_pernet_subsys(&net_inuse_ops)) 2574 panic("Cannot initialize net inuse counters"); 2575 2576 return 0; 2577 } 2578 2579 core_initcall(net_inuse_init); 2580 #else 2581 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2582 2583 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2584 { 2585 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2586 } 2587 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2588 2589 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2590 { 2591 int cpu, idx = prot->inuse_idx; 2592 int res = 0; 2593 2594 for_each_possible_cpu(cpu) 2595 res += per_cpu(prot_inuse, cpu).val[idx]; 2596 2597 return res >= 0 ? res : 0; 2598 } 2599 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2600 #endif 2601 2602 static void assign_proto_idx(struct proto *prot) 2603 { 2604 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2605 2606 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2607 pr_err("PROTO_INUSE_NR exhausted\n"); 2608 return; 2609 } 2610 2611 set_bit(prot->inuse_idx, proto_inuse_idx); 2612 } 2613 2614 static void release_proto_idx(struct proto *prot) 2615 { 2616 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2617 clear_bit(prot->inuse_idx, proto_inuse_idx); 2618 } 2619 #else 2620 static inline void assign_proto_idx(struct proto *prot) 2621 { 2622 } 2623 2624 static inline void release_proto_idx(struct proto *prot) 2625 { 2626 } 2627 #endif 2628 2629 int proto_register(struct proto *prot, int alloc_slab) 2630 { 2631 if (alloc_slab) { 2632 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2633 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2634 NULL); 2635 2636 if (prot->slab == NULL) { 2637 pr_crit("%s: Can't create sock SLAB cache!\n", 2638 prot->name); 2639 goto out; 2640 } 2641 2642 if (prot->rsk_prot != NULL) { 2643 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name); 2644 if (prot->rsk_prot->slab_name == NULL) 2645 goto out_free_sock_slab; 2646 2647 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name, 2648 prot->rsk_prot->obj_size, 0, 2649 SLAB_HWCACHE_ALIGN, NULL); 2650 2651 if (prot->rsk_prot->slab == NULL) { 2652 pr_crit("%s: Can't create request sock SLAB cache!\n", 2653 prot->name); 2654 goto out_free_request_sock_slab_name; 2655 } 2656 } 2657 2658 if (prot->twsk_prot != NULL) { 2659 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2660 2661 if (prot->twsk_prot->twsk_slab_name == NULL) 2662 goto out_free_request_sock_slab; 2663 2664 prot->twsk_prot->twsk_slab = 2665 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2666 prot->twsk_prot->twsk_obj_size, 2667 0, 2668 SLAB_HWCACHE_ALIGN | 2669 prot->slab_flags, 2670 NULL); 2671 if (prot->twsk_prot->twsk_slab == NULL) 2672 goto out_free_timewait_sock_slab_name; 2673 } 2674 } 2675 2676 mutex_lock(&proto_list_mutex); 2677 list_add(&prot->node, &proto_list); 2678 assign_proto_idx(prot); 2679 mutex_unlock(&proto_list_mutex); 2680 return 0; 2681 2682 out_free_timewait_sock_slab_name: 2683 kfree(prot->twsk_prot->twsk_slab_name); 2684 out_free_request_sock_slab: 2685 if (prot->rsk_prot && prot->rsk_prot->slab) { 2686 kmem_cache_destroy(prot->rsk_prot->slab); 2687 prot->rsk_prot->slab = NULL; 2688 } 2689 out_free_request_sock_slab_name: 2690 if (prot->rsk_prot) 2691 kfree(prot->rsk_prot->slab_name); 2692 out_free_sock_slab: 2693 kmem_cache_destroy(prot->slab); 2694 prot->slab = NULL; 2695 out: 2696 return -ENOBUFS; 2697 } 2698 EXPORT_SYMBOL(proto_register); 2699 2700 void proto_unregister(struct proto *prot) 2701 { 2702 mutex_lock(&proto_list_mutex); 2703 release_proto_idx(prot); 2704 list_del(&prot->node); 2705 mutex_unlock(&proto_list_mutex); 2706 2707 if (prot->slab != NULL) { 2708 kmem_cache_destroy(prot->slab); 2709 prot->slab = NULL; 2710 } 2711 2712 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) { 2713 kmem_cache_destroy(prot->rsk_prot->slab); 2714 kfree(prot->rsk_prot->slab_name); 2715 prot->rsk_prot->slab = NULL; 2716 } 2717 2718 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2719 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2720 kfree(prot->twsk_prot->twsk_slab_name); 2721 prot->twsk_prot->twsk_slab = NULL; 2722 } 2723 } 2724 EXPORT_SYMBOL(proto_unregister); 2725 2726 #ifdef CONFIG_PROC_FS 2727 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2728 __acquires(proto_list_mutex) 2729 { 2730 mutex_lock(&proto_list_mutex); 2731 return seq_list_start_head(&proto_list, *pos); 2732 } 2733 2734 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2735 { 2736 return seq_list_next(v, &proto_list, pos); 2737 } 2738 2739 static void proto_seq_stop(struct seq_file *seq, void *v) 2740 __releases(proto_list_mutex) 2741 { 2742 mutex_unlock(&proto_list_mutex); 2743 } 2744 2745 static char proto_method_implemented(const void *method) 2746 { 2747 return method == NULL ? 'n' : 'y'; 2748 } 2749 static long sock_prot_memory_allocated(struct proto *proto) 2750 { 2751 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 2752 } 2753 2754 static char *sock_prot_memory_pressure(struct proto *proto) 2755 { 2756 return proto->memory_pressure != NULL ? 2757 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 2758 } 2759 2760 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 2761 { 2762 2763 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 2764 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 2765 proto->name, 2766 proto->obj_size, 2767 sock_prot_inuse_get(seq_file_net(seq), proto), 2768 sock_prot_memory_allocated(proto), 2769 sock_prot_memory_pressure(proto), 2770 proto->max_header, 2771 proto->slab == NULL ? "no" : "yes", 2772 module_name(proto->owner), 2773 proto_method_implemented(proto->close), 2774 proto_method_implemented(proto->connect), 2775 proto_method_implemented(proto->disconnect), 2776 proto_method_implemented(proto->accept), 2777 proto_method_implemented(proto->ioctl), 2778 proto_method_implemented(proto->init), 2779 proto_method_implemented(proto->destroy), 2780 proto_method_implemented(proto->shutdown), 2781 proto_method_implemented(proto->setsockopt), 2782 proto_method_implemented(proto->getsockopt), 2783 proto_method_implemented(proto->sendmsg), 2784 proto_method_implemented(proto->recvmsg), 2785 proto_method_implemented(proto->sendpage), 2786 proto_method_implemented(proto->bind), 2787 proto_method_implemented(proto->backlog_rcv), 2788 proto_method_implemented(proto->hash), 2789 proto_method_implemented(proto->unhash), 2790 proto_method_implemented(proto->get_port), 2791 proto_method_implemented(proto->enter_memory_pressure)); 2792 } 2793 2794 static int proto_seq_show(struct seq_file *seq, void *v) 2795 { 2796 if (v == &proto_list) 2797 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 2798 "protocol", 2799 "size", 2800 "sockets", 2801 "memory", 2802 "press", 2803 "maxhdr", 2804 "slab", 2805 "module", 2806 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 2807 else 2808 proto_seq_printf(seq, list_entry(v, struct proto, node)); 2809 return 0; 2810 } 2811 2812 static const struct seq_operations proto_seq_ops = { 2813 .start = proto_seq_start, 2814 .next = proto_seq_next, 2815 .stop = proto_seq_stop, 2816 .show = proto_seq_show, 2817 }; 2818 2819 static int proto_seq_open(struct inode *inode, struct file *file) 2820 { 2821 return seq_open_net(inode, file, &proto_seq_ops, 2822 sizeof(struct seq_net_private)); 2823 } 2824 2825 static const struct file_operations proto_seq_fops = { 2826 .owner = THIS_MODULE, 2827 .open = proto_seq_open, 2828 .read = seq_read, 2829 .llseek = seq_lseek, 2830 .release = seq_release_net, 2831 }; 2832 2833 static __net_init int proto_init_net(struct net *net) 2834 { 2835 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops)) 2836 return -ENOMEM; 2837 2838 return 0; 2839 } 2840 2841 static __net_exit void proto_exit_net(struct net *net) 2842 { 2843 remove_proc_entry("protocols", net->proc_net); 2844 } 2845 2846 2847 static __net_initdata struct pernet_operations proto_net_ops = { 2848 .init = proto_init_net, 2849 .exit = proto_exit_net, 2850 }; 2851 2852 static int __init proto_init(void) 2853 { 2854 return register_pernet_subsys(&proto_net_ops); 2855 } 2856 2857 subsys_initcall(proto_init); 2858 2859 #endif /* PROC_FS */ 2860