1 /* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * Generic socket support routines. Memory allocators, socket lock/release 7 * handler for protocols to use and generic option handler. 8 * 9 * 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Florian La Roche, <flla@stud.uni-sb.de> 13 * Alan Cox, <A.Cox@swansea.ac.uk> 14 * 15 * Fixes: 16 * Alan Cox : Numerous verify_area() problems 17 * Alan Cox : Connecting on a connecting socket 18 * now returns an error for tcp. 19 * Alan Cox : sock->protocol is set correctly. 20 * and is not sometimes left as 0. 21 * Alan Cox : connect handles icmp errors on a 22 * connect properly. Unfortunately there 23 * is a restart syscall nasty there. I 24 * can't match BSD without hacking the C 25 * library. Ideas urgently sought! 26 * Alan Cox : Disallow bind() to addresses that are 27 * not ours - especially broadcast ones!! 28 * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost) 29 * Alan Cox : sock_wfree/sock_rfree don't destroy sockets, 30 * instead they leave that for the DESTROY timer. 31 * Alan Cox : Clean up error flag in accept 32 * Alan Cox : TCP ack handling is buggy, the DESTROY timer 33 * was buggy. Put a remove_sock() in the handler 34 * for memory when we hit 0. Also altered the timer 35 * code. The ACK stuff can wait and needs major 36 * TCP layer surgery. 37 * Alan Cox : Fixed TCP ack bug, removed remove sock 38 * and fixed timer/inet_bh race. 39 * Alan Cox : Added zapped flag for TCP 40 * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code 41 * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb 42 * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources 43 * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing. 44 * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so... 45 * Rick Sladkey : Relaxed UDP rules for matching packets. 46 * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support 47 * Pauline Middelink : identd support 48 * Alan Cox : Fixed connect() taking signals I think. 49 * Alan Cox : SO_LINGER supported 50 * Alan Cox : Error reporting fixes 51 * Anonymous : inet_create tidied up (sk->reuse setting) 52 * Alan Cox : inet sockets don't set sk->type! 53 * Alan Cox : Split socket option code 54 * Alan Cox : Callbacks 55 * Alan Cox : Nagle flag for Charles & Johannes stuff 56 * Alex : Removed restriction on inet fioctl 57 * Alan Cox : Splitting INET from NET core 58 * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt() 59 * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code 60 * Alan Cox : Split IP from generic code 61 * Alan Cox : New kfree_skbmem() 62 * Alan Cox : Make SO_DEBUG superuser only. 63 * Alan Cox : Allow anyone to clear SO_DEBUG 64 * (compatibility fix) 65 * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput. 66 * Alan Cox : Allocator for a socket is settable. 67 * Alan Cox : SO_ERROR includes soft errors. 68 * Alan Cox : Allow NULL arguments on some SO_ opts 69 * Alan Cox : Generic socket allocation to make hooks 70 * easier (suggested by Craig Metz). 71 * Michael Pall : SO_ERROR returns positive errno again 72 * Steve Whitehouse: Added default destructor to free 73 * protocol private data. 74 * Steve Whitehouse: Added various other default routines 75 * common to several socket families. 76 * Chris Evans : Call suser() check last on F_SETOWN 77 * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER. 78 * Andi Kleen : Add sock_kmalloc()/sock_kfree_s() 79 * Andi Kleen : Fix write_space callback 80 * Chris Evans : Security fixes - signedness again 81 * Arnaldo C. Melo : cleanups, use skb_queue_purge 82 * 83 * To Fix: 84 * 85 * 86 * This program is free software; you can redistribute it and/or 87 * modify it under the terms of the GNU General Public License 88 * as published by the Free Software Foundation; either version 89 * 2 of the License, or (at your option) any later version. 90 */ 91 92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 93 94 #include <linux/capability.h> 95 #include <linux/errno.h> 96 #include <linux/errqueue.h> 97 #include <linux/types.h> 98 #include <linux/socket.h> 99 #include <linux/in.h> 100 #include <linux/kernel.h> 101 #include <linux/module.h> 102 #include <linux/proc_fs.h> 103 #include <linux/seq_file.h> 104 #include <linux/sched.h> 105 #include <linux/timer.h> 106 #include <linux/string.h> 107 #include <linux/sockios.h> 108 #include <linux/net.h> 109 #include <linux/mm.h> 110 #include <linux/slab.h> 111 #include <linux/interrupt.h> 112 #include <linux/poll.h> 113 #include <linux/tcp.h> 114 #include <linux/init.h> 115 #include <linux/highmem.h> 116 #include <linux/user_namespace.h> 117 #include <linux/static_key.h> 118 #include <linux/memcontrol.h> 119 #include <linux/prefetch.h> 120 121 #include <asm/uaccess.h> 122 123 #include <linux/netdevice.h> 124 #include <net/protocol.h> 125 #include <linux/skbuff.h> 126 #include <net/net_namespace.h> 127 #include <net/request_sock.h> 128 #include <net/sock.h> 129 #include <linux/net_tstamp.h> 130 #include <net/xfrm.h> 131 #include <linux/ipsec.h> 132 #include <net/cls_cgroup.h> 133 #include <net/netprio_cgroup.h> 134 135 #include <linux/filter.h> 136 137 #include <trace/events/sock.h> 138 139 #ifdef CONFIG_INET 140 #include <net/tcp.h> 141 #endif 142 143 #include <net/busy_poll.h> 144 145 static DEFINE_MUTEX(proto_list_mutex); 146 static LIST_HEAD(proto_list); 147 148 #ifdef CONFIG_MEMCG_KMEM 149 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss) 150 { 151 struct proto *proto; 152 int ret = 0; 153 154 mutex_lock(&proto_list_mutex); 155 list_for_each_entry(proto, &proto_list, node) { 156 if (proto->init_cgroup) { 157 ret = proto->init_cgroup(memcg, ss); 158 if (ret) 159 goto out; 160 } 161 } 162 163 mutex_unlock(&proto_list_mutex); 164 return ret; 165 out: 166 list_for_each_entry_continue_reverse(proto, &proto_list, node) 167 if (proto->destroy_cgroup) 168 proto->destroy_cgroup(memcg); 169 mutex_unlock(&proto_list_mutex); 170 return ret; 171 } 172 173 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg) 174 { 175 struct proto *proto; 176 177 mutex_lock(&proto_list_mutex); 178 list_for_each_entry_reverse(proto, &proto_list, node) 179 if (proto->destroy_cgroup) 180 proto->destroy_cgroup(memcg); 181 mutex_unlock(&proto_list_mutex); 182 } 183 #endif 184 185 /* 186 * Each address family might have different locking rules, so we have 187 * one slock key per address family: 188 */ 189 static struct lock_class_key af_family_keys[AF_MAX]; 190 static struct lock_class_key af_family_slock_keys[AF_MAX]; 191 192 #if defined(CONFIG_MEMCG_KMEM) 193 struct static_key memcg_socket_limit_enabled; 194 EXPORT_SYMBOL(memcg_socket_limit_enabled); 195 #endif 196 197 /* 198 * Make lock validator output more readable. (we pre-construct these 199 * strings build-time, so that runtime initialization of socket 200 * locks is fast): 201 */ 202 static const char *const af_family_key_strings[AF_MAX+1] = { 203 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" , 204 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK", 205 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" , 206 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" , 207 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" , 208 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" , 209 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" , 210 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" , 211 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" , 212 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" , 213 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" , 214 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" , 215 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" , 216 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX" 217 }; 218 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 219 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" , 220 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK", 221 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" , 222 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" , 223 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" , 224 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" , 225 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" , 226 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" , 227 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" , 228 "slock-27" , "slock-28" , "slock-AF_CAN" , 229 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" , 230 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" , 231 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" , 232 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX" 233 }; 234 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 235 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" , 236 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK", 237 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" , 238 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" , 239 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" , 240 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" , 241 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" , 242 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" , 243 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" , 244 "clock-27" , "clock-28" , "clock-AF_CAN" , 245 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" , 246 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" , 247 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" , 248 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX" 249 }; 250 251 /* 252 * sk_callback_lock locking rules are per-address-family, 253 * so split the lock classes by using a per-AF key: 254 */ 255 static struct lock_class_key af_callback_keys[AF_MAX]; 256 257 /* Take into consideration the size of the struct sk_buff overhead in the 258 * determination of these values, since that is non-constant across 259 * platforms. This makes socket queueing behavior and performance 260 * not depend upon such differences. 261 */ 262 #define _SK_MEM_PACKETS 256 263 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 264 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 265 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 266 267 /* Run time adjustable parameters. */ 268 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 269 EXPORT_SYMBOL(sysctl_wmem_max); 270 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 271 EXPORT_SYMBOL(sysctl_rmem_max); 272 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 273 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 274 275 /* Maximal space eaten by iovec or ancillary data plus some space */ 276 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); 277 EXPORT_SYMBOL(sysctl_optmem_max); 278 279 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE; 280 EXPORT_SYMBOL_GPL(memalloc_socks); 281 282 /** 283 * sk_set_memalloc - sets %SOCK_MEMALLOC 284 * @sk: socket to set it on 285 * 286 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 287 * It's the responsibility of the admin to adjust min_free_kbytes 288 * to meet the requirements 289 */ 290 void sk_set_memalloc(struct sock *sk) 291 { 292 sock_set_flag(sk, SOCK_MEMALLOC); 293 sk->sk_allocation |= __GFP_MEMALLOC; 294 static_key_slow_inc(&memalloc_socks); 295 } 296 EXPORT_SYMBOL_GPL(sk_set_memalloc); 297 298 void sk_clear_memalloc(struct sock *sk) 299 { 300 sock_reset_flag(sk, SOCK_MEMALLOC); 301 sk->sk_allocation &= ~__GFP_MEMALLOC; 302 static_key_slow_dec(&memalloc_socks); 303 304 /* 305 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 306 * progress of swapping. However, if SOCK_MEMALLOC is cleared while 307 * it has rmem allocations there is a risk that the user of the 308 * socket cannot make forward progress due to exceeding the rmem 309 * limits. By rights, sk_clear_memalloc() should only be called 310 * on sockets being torn down but warn and reset the accounting if 311 * that assumption breaks. 312 */ 313 if (WARN_ON(sk->sk_forward_alloc)) 314 sk_mem_reclaim(sk); 315 } 316 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 317 318 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 319 { 320 int ret; 321 unsigned long pflags = current->flags; 322 323 /* these should have been dropped before queueing */ 324 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 325 326 current->flags |= PF_MEMALLOC; 327 ret = sk->sk_backlog_rcv(sk, skb); 328 tsk_restore_flags(current, pflags, PF_MEMALLOC); 329 330 return ret; 331 } 332 EXPORT_SYMBOL(__sk_backlog_rcv); 333 334 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen) 335 { 336 struct timeval tv; 337 338 if (optlen < sizeof(tv)) 339 return -EINVAL; 340 if (copy_from_user(&tv, optval, sizeof(tv))) 341 return -EFAULT; 342 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 343 return -EDOM; 344 345 if (tv.tv_sec < 0) { 346 static int warned __read_mostly; 347 348 *timeo_p = 0; 349 if (warned < 10 && net_ratelimit()) { 350 warned++; 351 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 352 __func__, current->comm, task_pid_nr(current)); 353 } 354 return 0; 355 } 356 *timeo_p = MAX_SCHEDULE_TIMEOUT; 357 if (tv.tv_sec == 0 && tv.tv_usec == 0) 358 return 0; 359 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1)) 360 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ); 361 return 0; 362 } 363 364 static void sock_warn_obsolete_bsdism(const char *name) 365 { 366 static int warned; 367 static char warncomm[TASK_COMM_LEN]; 368 if (strcmp(warncomm, current->comm) && warned < 5) { 369 strcpy(warncomm, current->comm); 370 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", 371 warncomm, name); 372 warned++; 373 } 374 } 375 376 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 377 378 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 379 { 380 if (sk->sk_flags & flags) { 381 sk->sk_flags &= ~flags; 382 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 383 net_disable_timestamp(); 384 } 385 } 386 387 388 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 389 { 390 int err; 391 int skb_len; 392 unsigned long flags; 393 struct sk_buff_head *list = &sk->sk_receive_queue; 394 395 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 396 atomic_inc(&sk->sk_drops); 397 trace_sock_rcvqueue_full(sk, skb); 398 return -ENOMEM; 399 } 400 401 err = sk_filter(sk, skb); 402 if (err) 403 return err; 404 405 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 406 atomic_inc(&sk->sk_drops); 407 return -ENOBUFS; 408 } 409 410 skb->dev = NULL; 411 skb_set_owner_r(skb, sk); 412 413 /* Cache the SKB length before we tack it onto the receive 414 * queue. Once it is added it no longer belongs to us and 415 * may be freed by other threads of control pulling packets 416 * from the queue. 417 */ 418 skb_len = skb->len; 419 420 /* we escape from rcu protected region, make sure we dont leak 421 * a norefcounted dst 422 */ 423 skb_dst_force(skb); 424 425 spin_lock_irqsave(&list->lock, flags); 426 skb->dropcount = atomic_read(&sk->sk_drops); 427 __skb_queue_tail(list, skb); 428 spin_unlock_irqrestore(&list->lock, flags); 429 430 if (!sock_flag(sk, SOCK_DEAD)) 431 sk->sk_data_ready(sk, skb_len); 432 return 0; 433 } 434 EXPORT_SYMBOL(sock_queue_rcv_skb); 435 436 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested) 437 { 438 int rc = NET_RX_SUCCESS; 439 440 if (sk_filter(sk, skb)) 441 goto discard_and_relse; 442 443 skb->dev = NULL; 444 445 if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) { 446 atomic_inc(&sk->sk_drops); 447 goto discard_and_relse; 448 } 449 if (nested) 450 bh_lock_sock_nested(sk); 451 else 452 bh_lock_sock(sk); 453 if (!sock_owned_by_user(sk)) { 454 /* 455 * trylock + unlock semantics: 456 */ 457 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 458 459 rc = sk_backlog_rcv(sk, skb); 460 461 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 462 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 463 bh_unlock_sock(sk); 464 atomic_inc(&sk->sk_drops); 465 goto discard_and_relse; 466 } 467 468 bh_unlock_sock(sk); 469 out: 470 sock_put(sk); 471 return rc; 472 discard_and_relse: 473 kfree_skb(skb); 474 goto out; 475 } 476 EXPORT_SYMBOL(sk_receive_skb); 477 478 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 479 { 480 struct dst_entry *dst = __sk_dst_get(sk); 481 482 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 483 sk_tx_queue_clear(sk); 484 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 485 dst_release(dst); 486 return NULL; 487 } 488 489 return dst; 490 } 491 EXPORT_SYMBOL(__sk_dst_check); 492 493 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 494 { 495 struct dst_entry *dst = sk_dst_get(sk); 496 497 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 498 sk_dst_reset(sk); 499 dst_release(dst); 500 return NULL; 501 } 502 503 return dst; 504 } 505 EXPORT_SYMBOL(sk_dst_check); 506 507 static int sock_setbindtodevice(struct sock *sk, char __user *optval, 508 int optlen) 509 { 510 int ret = -ENOPROTOOPT; 511 #ifdef CONFIG_NETDEVICES 512 struct net *net = sock_net(sk); 513 char devname[IFNAMSIZ]; 514 int index; 515 516 /* Sorry... */ 517 ret = -EPERM; 518 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 519 goto out; 520 521 ret = -EINVAL; 522 if (optlen < 0) 523 goto out; 524 525 /* Bind this socket to a particular device like "eth0", 526 * as specified in the passed interface name. If the 527 * name is "" or the option length is zero the socket 528 * is not bound. 529 */ 530 if (optlen > IFNAMSIZ - 1) 531 optlen = IFNAMSIZ - 1; 532 memset(devname, 0, sizeof(devname)); 533 534 ret = -EFAULT; 535 if (copy_from_user(devname, optval, optlen)) 536 goto out; 537 538 index = 0; 539 if (devname[0] != '\0') { 540 struct net_device *dev; 541 542 rcu_read_lock(); 543 dev = dev_get_by_name_rcu(net, devname); 544 if (dev) 545 index = dev->ifindex; 546 rcu_read_unlock(); 547 ret = -ENODEV; 548 if (!dev) 549 goto out; 550 } 551 552 lock_sock(sk); 553 sk->sk_bound_dev_if = index; 554 sk_dst_reset(sk); 555 release_sock(sk); 556 557 ret = 0; 558 559 out: 560 #endif 561 562 return ret; 563 } 564 565 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 566 int __user *optlen, int len) 567 { 568 int ret = -ENOPROTOOPT; 569 #ifdef CONFIG_NETDEVICES 570 struct net *net = sock_net(sk); 571 char devname[IFNAMSIZ]; 572 573 if (sk->sk_bound_dev_if == 0) { 574 len = 0; 575 goto zero; 576 } 577 578 ret = -EINVAL; 579 if (len < IFNAMSIZ) 580 goto out; 581 582 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); 583 if (ret) 584 goto out; 585 586 len = strlen(devname) + 1; 587 588 ret = -EFAULT; 589 if (copy_to_user(optval, devname, len)) 590 goto out; 591 592 zero: 593 ret = -EFAULT; 594 if (put_user(len, optlen)) 595 goto out; 596 597 ret = 0; 598 599 out: 600 #endif 601 602 return ret; 603 } 604 605 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) 606 { 607 if (valbool) 608 sock_set_flag(sk, bit); 609 else 610 sock_reset_flag(sk, bit); 611 } 612 613 /* 614 * This is meant for all protocols to use and covers goings on 615 * at the socket level. Everything here is generic. 616 */ 617 618 int sock_setsockopt(struct socket *sock, int level, int optname, 619 char __user *optval, unsigned int optlen) 620 { 621 struct sock *sk = sock->sk; 622 int val; 623 int valbool; 624 struct linger ling; 625 int ret = 0; 626 627 /* 628 * Options without arguments 629 */ 630 631 if (optname == SO_BINDTODEVICE) 632 return sock_setbindtodevice(sk, optval, optlen); 633 634 if (optlen < sizeof(int)) 635 return -EINVAL; 636 637 if (get_user(val, (int __user *)optval)) 638 return -EFAULT; 639 640 valbool = val ? 1 : 0; 641 642 lock_sock(sk); 643 644 switch (optname) { 645 case SO_DEBUG: 646 if (val && !capable(CAP_NET_ADMIN)) 647 ret = -EACCES; 648 else 649 sock_valbool_flag(sk, SOCK_DBG, valbool); 650 break; 651 case SO_REUSEADDR: 652 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 653 break; 654 case SO_REUSEPORT: 655 sk->sk_reuseport = valbool; 656 break; 657 case SO_TYPE: 658 case SO_PROTOCOL: 659 case SO_DOMAIN: 660 case SO_ERROR: 661 ret = -ENOPROTOOPT; 662 break; 663 case SO_DONTROUTE: 664 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 665 break; 666 case SO_BROADCAST: 667 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 668 break; 669 case SO_SNDBUF: 670 /* Don't error on this BSD doesn't and if you think 671 * about it this is right. Otherwise apps have to 672 * play 'guess the biggest size' games. RCVBUF/SNDBUF 673 * are treated in BSD as hints 674 */ 675 val = min_t(u32, val, sysctl_wmem_max); 676 set_sndbuf: 677 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 678 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF); 679 /* Wake up sending tasks if we upped the value. */ 680 sk->sk_write_space(sk); 681 break; 682 683 case SO_SNDBUFFORCE: 684 if (!capable(CAP_NET_ADMIN)) { 685 ret = -EPERM; 686 break; 687 } 688 goto set_sndbuf; 689 690 case SO_RCVBUF: 691 /* Don't error on this BSD doesn't and if you think 692 * about it this is right. Otherwise apps have to 693 * play 'guess the biggest size' games. RCVBUF/SNDBUF 694 * are treated in BSD as hints 695 */ 696 val = min_t(u32, val, sysctl_rmem_max); 697 set_rcvbuf: 698 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 699 /* 700 * We double it on the way in to account for 701 * "struct sk_buff" etc. overhead. Applications 702 * assume that the SO_RCVBUF setting they make will 703 * allow that much actual data to be received on that 704 * socket. 705 * 706 * Applications are unaware that "struct sk_buff" and 707 * other overheads allocate from the receive buffer 708 * during socket buffer allocation. 709 * 710 * And after considering the possible alternatives, 711 * returning the value we actually used in getsockopt 712 * is the most desirable behavior. 713 */ 714 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF); 715 break; 716 717 case SO_RCVBUFFORCE: 718 if (!capable(CAP_NET_ADMIN)) { 719 ret = -EPERM; 720 break; 721 } 722 goto set_rcvbuf; 723 724 case SO_KEEPALIVE: 725 #ifdef CONFIG_INET 726 if (sk->sk_protocol == IPPROTO_TCP && 727 sk->sk_type == SOCK_STREAM) 728 tcp_set_keepalive(sk, valbool); 729 #endif 730 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 731 break; 732 733 case SO_OOBINLINE: 734 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 735 break; 736 737 case SO_NO_CHECK: 738 sk->sk_no_check = valbool; 739 break; 740 741 case SO_PRIORITY: 742 if ((val >= 0 && val <= 6) || 743 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 744 sk->sk_priority = val; 745 else 746 ret = -EPERM; 747 break; 748 749 case SO_LINGER: 750 if (optlen < sizeof(ling)) { 751 ret = -EINVAL; /* 1003.1g */ 752 break; 753 } 754 if (copy_from_user(&ling, optval, sizeof(ling))) { 755 ret = -EFAULT; 756 break; 757 } 758 if (!ling.l_onoff) 759 sock_reset_flag(sk, SOCK_LINGER); 760 else { 761 #if (BITS_PER_LONG == 32) 762 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 763 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 764 else 765 #endif 766 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 767 sock_set_flag(sk, SOCK_LINGER); 768 } 769 break; 770 771 case SO_BSDCOMPAT: 772 sock_warn_obsolete_bsdism("setsockopt"); 773 break; 774 775 case SO_PASSCRED: 776 if (valbool) 777 set_bit(SOCK_PASSCRED, &sock->flags); 778 else 779 clear_bit(SOCK_PASSCRED, &sock->flags); 780 break; 781 782 case SO_TIMESTAMP: 783 case SO_TIMESTAMPNS: 784 if (valbool) { 785 if (optname == SO_TIMESTAMP) 786 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 787 else 788 sock_set_flag(sk, SOCK_RCVTSTAMPNS); 789 sock_set_flag(sk, SOCK_RCVTSTAMP); 790 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 791 } else { 792 sock_reset_flag(sk, SOCK_RCVTSTAMP); 793 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 794 } 795 break; 796 797 case SO_TIMESTAMPING: 798 if (val & ~SOF_TIMESTAMPING_MASK) { 799 ret = -EINVAL; 800 break; 801 } 802 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE, 803 val & SOF_TIMESTAMPING_TX_HARDWARE); 804 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE, 805 val & SOF_TIMESTAMPING_TX_SOFTWARE); 806 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE, 807 val & SOF_TIMESTAMPING_RX_HARDWARE); 808 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 809 sock_enable_timestamp(sk, 810 SOCK_TIMESTAMPING_RX_SOFTWARE); 811 else 812 sock_disable_timestamp(sk, 813 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 814 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE, 815 val & SOF_TIMESTAMPING_SOFTWARE); 816 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE, 817 val & SOF_TIMESTAMPING_SYS_HARDWARE); 818 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE, 819 val & SOF_TIMESTAMPING_RAW_HARDWARE); 820 break; 821 822 case SO_RCVLOWAT: 823 if (val < 0) 824 val = INT_MAX; 825 sk->sk_rcvlowat = val ? : 1; 826 break; 827 828 case SO_RCVTIMEO: 829 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); 830 break; 831 832 case SO_SNDTIMEO: 833 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); 834 break; 835 836 case SO_ATTACH_FILTER: 837 ret = -EINVAL; 838 if (optlen == sizeof(struct sock_fprog)) { 839 struct sock_fprog fprog; 840 841 ret = -EFAULT; 842 if (copy_from_user(&fprog, optval, sizeof(fprog))) 843 break; 844 845 ret = sk_attach_filter(&fprog, sk); 846 } 847 break; 848 849 case SO_DETACH_FILTER: 850 ret = sk_detach_filter(sk); 851 break; 852 853 case SO_LOCK_FILTER: 854 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 855 ret = -EPERM; 856 else 857 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 858 break; 859 860 case SO_PASSSEC: 861 if (valbool) 862 set_bit(SOCK_PASSSEC, &sock->flags); 863 else 864 clear_bit(SOCK_PASSSEC, &sock->flags); 865 break; 866 case SO_MARK: 867 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 868 ret = -EPERM; 869 else 870 sk->sk_mark = val; 871 break; 872 873 /* We implement the SO_SNDLOWAT etc to 874 not be settable (1003.1g 5.3) */ 875 case SO_RXQ_OVFL: 876 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 877 break; 878 879 case SO_WIFI_STATUS: 880 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 881 break; 882 883 case SO_PEEK_OFF: 884 if (sock->ops->set_peek_off) 885 ret = sock->ops->set_peek_off(sk, val); 886 else 887 ret = -EOPNOTSUPP; 888 break; 889 890 case SO_NOFCS: 891 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 892 break; 893 894 case SO_SELECT_ERR_QUEUE: 895 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 896 break; 897 898 #ifdef CONFIG_NET_RX_BUSY_POLL 899 case SO_BUSY_POLL: 900 /* allow unprivileged users to decrease the value */ 901 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN)) 902 ret = -EPERM; 903 else { 904 if (val < 0) 905 ret = -EINVAL; 906 else 907 sk->sk_ll_usec = val; 908 } 909 break; 910 #endif 911 912 case SO_MAX_PACING_RATE: 913 sk->sk_max_pacing_rate = val; 914 sk->sk_pacing_rate = min(sk->sk_pacing_rate, 915 sk->sk_max_pacing_rate); 916 break; 917 918 default: 919 ret = -ENOPROTOOPT; 920 break; 921 } 922 release_sock(sk); 923 return ret; 924 } 925 EXPORT_SYMBOL(sock_setsockopt); 926 927 928 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 929 struct ucred *ucred) 930 { 931 ucred->pid = pid_vnr(pid); 932 ucred->uid = ucred->gid = -1; 933 if (cred) { 934 struct user_namespace *current_ns = current_user_ns(); 935 936 ucred->uid = from_kuid_munged(current_ns, cred->euid); 937 ucred->gid = from_kgid_munged(current_ns, cred->egid); 938 } 939 } 940 941 int sock_getsockopt(struct socket *sock, int level, int optname, 942 char __user *optval, int __user *optlen) 943 { 944 struct sock *sk = sock->sk; 945 946 union { 947 int val; 948 struct linger ling; 949 struct timeval tm; 950 } v; 951 952 int lv = sizeof(int); 953 int len; 954 955 if (get_user(len, optlen)) 956 return -EFAULT; 957 if (len < 0) 958 return -EINVAL; 959 960 memset(&v, 0, sizeof(v)); 961 962 switch (optname) { 963 case SO_DEBUG: 964 v.val = sock_flag(sk, SOCK_DBG); 965 break; 966 967 case SO_DONTROUTE: 968 v.val = sock_flag(sk, SOCK_LOCALROUTE); 969 break; 970 971 case SO_BROADCAST: 972 v.val = sock_flag(sk, SOCK_BROADCAST); 973 break; 974 975 case SO_SNDBUF: 976 v.val = sk->sk_sndbuf; 977 break; 978 979 case SO_RCVBUF: 980 v.val = sk->sk_rcvbuf; 981 break; 982 983 case SO_REUSEADDR: 984 v.val = sk->sk_reuse; 985 break; 986 987 case SO_REUSEPORT: 988 v.val = sk->sk_reuseport; 989 break; 990 991 case SO_KEEPALIVE: 992 v.val = sock_flag(sk, SOCK_KEEPOPEN); 993 break; 994 995 case SO_TYPE: 996 v.val = sk->sk_type; 997 break; 998 999 case SO_PROTOCOL: 1000 v.val = sk->sk_protocol; 1001 break; 1002 1003 case SO_DOMAIN: 1004 v.val = sk->sk_family; 1005 break; 1006 1007 case SO_ERROR: 1008 v.val = -sock_error(sk); 1009 if (v.val == 0) 1010 v.val = xchg(&sk->sk_err_soft, 0); 1011 break; 1012 1013 case SO_OOBINLINE: 1014 v.val = sock_flag(sk, SOCK_URGINLINE); 1015 break; 1016 1017 case SO_NO_CHECK: 1018 v.val = sk->sk_no_check; 1019 break; 1020 1021 case SO_PRIORITY: 1022 v.val = sk->sk_priority; 1023 break; 1024 1025 case SO_LINGER: 1026 lv = sizeof(v.ling); 1027 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1028 v.ling.l_linger = sk->sk_lingertime / HZ; 1029 break; 1030 1031 case SO_BSDCOMPAT: 1032 sock_warn_obsolete_bsdism("getsockopt"); 1033 break; 1034 1035 case SO_TIMESTAMP: 1036 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1037 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1038 break; 1039 1040 case SO_TIMESTAMPNS: 1041 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 1042 break; 1043 1044 case SO_TIMESTAMPING: 1045 v.val = 0; 1046 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE)) 1047 v.val |= SOF_TIMESTAMPING_TX_HARDWARE; 1048 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE)) 1049 v.val |= SOF_TIMESTAMPING_TX_SOFTWARE; 1050 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE)) 1051 v.val |= SOF_TIMESTAMPING_RX_HARDWARE; 1052 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE)) 1053 v.val |= SOF_TIMESTAMPING_RX_SOFTWARE; 1054 if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) 1055 v.val |= SOF_TIMESTAMPING_SOFTWARE; 1056 if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)) 1057 v.val |= SOF_TIMESTAMPING_SYS_HARDWARE; 1058 if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) 1059 v.val |= SOF_TIMESTAMPING_RAW_HARDWARE; 1060 break; 1061 1062 case SO_RCVTIMEO: 1063 lv = sizeof(struct timeval); 1064 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 1065 v.tm.tv_sec = 0; 1066 v.tm.tv_usec = 0; 1067 } else { 1068 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 1069 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 1070 } 1071 break; 1072 1073 case SO_SNDTIMEO: 1074 lv = sizeof(struct timeval); 1075 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 1076 v.tm.tv_sec = 0; 1077 v.tm.tv_usec = 0; 1078 } else { 1079 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1080 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1081 } 1082 break; 1083 1084 case SO_RCVLOWAT: 1085 v.val = sk->sk_rcvlowat; 1086 break; 1087 1088 case SO_SNDLOWAT: 1089 v.val = 1; 1090 break; 1091 1092 case SO_PASSCRED: 1093 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1094 break; 1095 1096 case SO_PEERCRED: 1097 { 1098 struct ucred peercred; 1099 if (len > sizeof(peercred)) 1100 len = sizeof(peercred); 1101 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1102 if (copy_to_user(optval, &peercred, len)) 1103 return -EFAULT; 1104 goto lenout; 1105 } 1106 1107 case SO_PEERNAME: 1108 { 1109 char address[128]; 1110 1111 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1112 return -ENOTCONN; 1113 if (lv < len) 1114 return -EINVAL; 1115 if (copy_to_user(optval, address, len)) 1116 return -EFAULT; 1117 goto lenout; 1118 } 1119 1120 /* Dubious BSD thing... Probably nobody even uses it, but 1121 * the UNIX standard wants it for whatever reason... -DaveM 1122 */ 1123 case SO_ACCEPTCONN: 1124 v.val = sk->sk_state == TCP_LISTEN; 1125 break; 1126 1127 case SO_PASSSEC: 1128 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1129 break; 1130 1131 case SO_PEERSEC: 1132 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1133 1134 case SO_MARK: 1135 v.val = sk->sk_mark; 1136 break; 1137 1138 case SO_RXQ_OVFL: 1139 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1140 break; 1141 1142 case SO_WIFI_STATUS: 1143 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1144 break; 1145 1146 case SO_PEEK_OFF: 1147 if (!sock->ops->set_peek_off) 1148 return -EOPNOTSUPP; 1149 1150 v.val = sk->sk_peek_off; 1151 break; 1152 case SO_NOFCS: 1153 v.val = sock_flag(sk, SOCK_NOFCS); 1154 break; 1155 1156 case SO_BINDTODEVICE: 1157 return sock_getbindtodevice(sk, optval, optlen, len); 1158 1159 case SO_GET_FILTER: 1160 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1161 if (len < 0) 1162 return len; 1163 1164 goto lenout; 1165 1166 case SO_LOCK_FILTER: 1167 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1168 break; 1169 1170 case SO_BPF_EXTENSIONS: 1171 v.val = bpf_tell_extensions(); 1172 break; 1173 1174 case SO_SELECT_ERR_QUEUE: 1175 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1176 break; 1177 1178 #ifdef CONFIG_NET_RX_BUSY_POLL 1179 case SO_BUSY_POLL: 1180 v.val = sk->sk_ll_usec; 1181 break; 1182 #endif 1183 1184 case SO_MAX_PACING_RATE: 1185 v.val = sk->sk_max_pacing_rate; 1186 break; 1187 1188 default: 1189 return -ENOPROTOOPT; 1190 } 1191 1192 if (len > lv) 1193 len = lv; 1194 if (copy_to_user(optval, &v, len)) 1195 return -EFAULT; 1196 lenout: 1197 if (put_user(len, optlen)) 1198 return -EFAULT; 1199 return 0; 1200 } 1201 1202 /* 1203 * Initialize an sk_lock. 1204 * 1205 * (We also register the sk_lock with the lock validator.) 1206 */ 1207 static inline void sock_lock_init(struct sock *sk) 1208 { 1209 sock_lock_init_class_and_name(sk, 1210 af_family_slock_key_strings[sk->sk_family], 1211 af_family_slock_keys + sk->sk_family, 1212 af_family_key_strings[sk->sk_family], 1213 af_family_keys + sk->sk_family); 1214 } 1215 1216 /* 1217 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1218 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1219 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1220 */ 1221 static void sock_copy(struct sock *nsk, const struct sock *osk) 1222 { 1223 #ifdef CONFIG_SECURITY_NETWORK 1224 void *sptr = nsk->sk_security; 1225 #endif 1226 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1227 1228 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1229 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1230 1231 #ifdef CONFIG_SECURITY_NETWORK 1232 nsk->sk_security = sptr; 1233 security_sk_clone(osk, nsk); 1234 #endif 1235 } 1236 1237 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size) 1238 { 1239 unsigned long nulls1, nulls2; 1240 1241 nulls1 = offsetof(struct sock, __sk_common.skc_node.next); 1242 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next); 1243 if (nulls1 > nulls2) 1244 swap(nulls1, nulls2); 1245 1246 if (nulls1 != 0) 1247 memset((char *)sk, 0, nulls1); 1248 memset((char *)sk + nulls1 + sizeof(void *), 0, 1249 nulls2 - nulls1 - sizeof(void *)); 1250 memset((char *)sk + nulls2 + sizeof(void *), 0, 1251 size - nulls2 - sizeof(void *)); 1252 } 1253 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls); 1254 1255 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1256 int family) 1257 { 1258 struct sock *sk; 1259 struct kmem_cache *slab; 1260 1261 slab = prot->slab; 1262 if (slab != NULL) { 1263 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1264 if (!sk) 1265 return sk; 1266 if (priority & __GFP_ZERO) { 1267 if (prot->clear_sk) 1268 prot->clear_sk(sk, prot->obj_size); 1269 else 1270 sk_prot_clear_nulls(sk, prot->obj_size); 1271 } 1272 } else 1273 sk = kmalloc(prot->obj_size, priority); 1274 1275 if (sk != NULL) { 1276 kmemcheck_annotate_bitfield(sk, flags); 1277 1278 if (security_sk_alloc(sk, family, priority)) 1279 goto out_free; 1280 1281 if (!try_module_get(prot->owner)) 1282 goto out_free_sec; 1283 sk_tx_queue_clear(sk); 1284 } 1285 1286 return sk; 1287 1288 out_free_sec: 1289 security_sk_free(sk); 1290 out_free: 1291 if (slab != NULL) 1292 kmem_cache_free(slab, sk); 1293 else 1294 kfree(sk); 1295 return NULL; 1296 } 1297 1298 static void sk_prot_free(struct proto *prot, struct sock *sk) 1299 { 1300 struct kmem_cache *slab; 1301 struct module *owner; 1302 1303 owner = prot->owner; 1304 slab = prot->slab; 1305 1306 security_sk_free(sk); 1307 if (slab != NULL) 1308 kmem_cache_free(slab, sk); 1309 else 1310 kfree(sk); 1311 module_put(owner); 1312 } 1313 1314 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO) 1315 void sock_update_netprioidx(struct sock *sk) 1316 { 1317 if (in_interrupt()) 1318 return; 1319 1320 sk->sk_cgrp_prioidx = task_netprioidx(current); 1321 } 1322 EXPORT_SYMBOL_GPL(sock_update_netprioidx); 1323 #endif 1324 1325 /** 1326 * sk_alloc - All socket objects are allocated here 1327 * @net: the applicable net namespace 1328 * @family: protocol family 1329 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1330 * @prot: struct proto associated with this new sock instance 1331 */ 1332 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1333 struct proto *prot) 1334 { 1335 struct sock *sk; 1336 1337 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1338 if (sk) { 1339 sk->sk_family = family; 1340 /* 1341 * See comment in struct sock definition to understand 1342 * why we need sk_prot_creator -acme 1343 */ 1344 sk->sk_prot = sk->sk_prot_creator = prot; 1345 sock_lock_init(sk); 1346 sock_net_set(sk, get_net(net)); 1347 atomic_set(&sk->sk_wmem_alloc, 1); 1348 1349 sock_update_classid(sk); 1350 sock_update_netprioidx(sk); 1351 } 1352 1353 return sk; 1354 } 1355 EXPORT_SYMBOL(sk_alloc); 1356 1357 static void __sk_free(struct sock *sk) 1358 { 1359 struct sk_filter *filter; 1360 1361 if (sk->sk_destruct) 1362 sk->sk_destruct(sk); 1363 1364 filter = rcu_dereference_check(sk->sk_filter, 1365 atomic_read(&sk->sk_wmem_alloc) == 0); 1366 if (filter) { 1367 sk_filter_uncharge(sk, filter); 1368 RCU_INIT_POINTER(sk->sk_filter, NULL); 1369 } 1370 1371 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1372 1373 if (atomic_read(&sk->sk_omem_alloc)) 1374 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1375 __func__, atomic_read(&sk->sk_omem_alloc)); 1376 1377 if (sk->sk_peer_cred) 1378 put_cred(sk->sk_peer_cred); 1379 put_pid(sk->sk_peer_pid); 1380 put_net(sock_net(sk)); 1381 sk_prot_free(sk->sk_prot_creator, sk); 1382 } 1383 1384 void sk_free(struct sock *sk) 1385 { 1386 /* 1387 * We subtract one from sk_wmem_alloc and can know if 1388 * some packets are still in some tx queue. 1389 * If not null, sock_wfree() will call __sk_free(sk) later 1390 */ 1391 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1392 __sk_free(sk); 1393 } 1394 EXPORT_SYMBOL(sk_free); 1395 1396 /* 1397 * Last sock_put should drop reference to sk->sk_net. It has already 1398 * been dropped in sk_change_net. Taking reference to stopping namespace 1399 * is not an option. 1400 * Take reference to a socket to remove it from hash _alive_ and after that 1401 * destroy it in the context of init_net. 1402 */ 1403 void sk_release_kernel(struct sock *sk) 1404 { 1405 if (sk == NULL || sk->sk_socket == NULL) 1406 return; 1407 1408 sock_hold(sk); 1409 sock_release(sk->sk_socket); 1410 release_net(sock_net(sk)); 1411 sock_net_set(sk, get_net(&init_net)); 1412 sock_put(sk); 1413 } 1414 EXPORT_SYMBOL(sk_release_kernel); 1415 1416 static void sk_update_clone(const struct sock *sk, struct sock *newsk) 1417 { 1418 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1419 sock_update_memcg(newsk); 1420 } 1421 1422 /** 1423 * sk_clone_lock - clone a socket, and lock its clone 1424 * @sk: the socket to clone 1425 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1426 * 1427 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1428 */ 1429 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1430 { 1431 struct sock *newsk; 1432 1433 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1434 if (newsk != NULL) { 1435 struct sk_filter *filter; 1436 1437 sock_copy(newsk, sk); 1438 1439 /* SANITY */ 1440 get_net(sock_net(newsk)); 1441 sk_node_init(&newsk->sk_node); 1442 sock_lock_init(newsk); 1443 bh_lock_sock(newsk); 1444 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1445 newsk->sk_backlog.len = 0; 1446 1447 atomic_set(&newsk->sk_rmem_alloc, 0); 1448 /* 1449 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1450 */ 1451 atomic_set(&newsk->sk_wmem_alloc, 1); 1452 atomic_set(&newsk->sk_omem_alloc, 0); 1453 skb_queue_head_init(&newsk->sk_receive_queue); 1454 skb_queue_head_init(&newsk->sk_write_queue); 1455 #ifdef CONFIG_NET_DMA 1456 skb_queue_head_init(&newsk->sk_async_wait_queue); 1457 #endif 1458 1459 spin_lock_init(&newsk->sk_dst_lock); 1460 rwlock_init(&newsk->sk_callback_lock); 1461 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1462 af_callback_keys + newsk->sk_family, 1463 af_family_clock_key_strings[newsk->sk_family]); 1464 1465 newsk->sk_dst_cache = NULL; 1466 newsk->sk_wmem_queued = 0; 1467 newsk->sk_forward_alloc = 0; 1468 newsk->sk_send_head = NULL; 1469 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1470 1471 sock_reset_flag(newsk, SOCK_DONE); 1472 skb_queue_head_init(&newsk->sk_error_queue); 1473 1474 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1475 if (filter != NULL) 1476 sk_filter_charge(newsk, filter); 1477 1478 if (unlikely(xfrm_sk_clone_policy(newsk))) { 1479 /* It is still raw copy of parent, so invalidate 1480 * destructor and make plain sk_free() */ 1481 newsk->sk_destruct = NULL; 1482 bh_unlock_sock(newsk); 1483 sk_free(newsk); 1484 newsk = NULL; 1485 goto out; 1486 } 1487 1488 newsk->sk_err = 0; 1489 newsk->sk_priority = 0; 1490 /* 1491 * Before updating sk_refcnt, we must commit prior changes to memory 1492 * (Documentation/RCU/rculist_nulls.txt for details) 1493 */ 1494 smp_wmb(); 1495 atomic_set(&newsk->sk_refcnt, 2); 1496 1497 /* 1498 * Increment the counter in the same struct proto as the master 1499 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1500 * is the same as sk->sk_prot->socks, as this field was copied 1501 * with memcpy). 1502 * 1503 * This _changes_ the previous behaviour, where 1504 * tcp_create_openreq_child always was incrementing the 1505 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1506 * to be taken into account in all callers. -acme 1507 */ 1508 sk_refcnt_debug_inc(newsk); 1509 sk_set_socket(newsk, NULL); 1510 newsk->sk_wq = NULL; 1511 1512 sk_update_clone(sk, newsk); 1513 1514 if (newsk->sk_prot->sockets_allocated) 1515 sk_sockets_allocated_inc(newsk); 1516 1517 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1518 net_enable_timestamp(); 1519 } 1520 out: 1521 return newsk; 1522 } 1523 EXPORT_SYMBOL_GPL(sk_clone_lock); 1524 1525 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1526 { 1527 __sk_dst_set(sk, dst); 1528 sk->sk_route_caps = dst->dev->features; 1529 if (sk->sk_route_caps & NETIF_F_GSO) 1530 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1531 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1532 if (sk_can_gso(sk)) { 1533 if (dst->header_len) { 1534 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1535 } else { 1536 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1537 sk->sk_gso_max_size = dst->dev->gso_max_size; 1538 sk->sk_gso_max_segs = dst->dev->gso_max_segs; 1539 } 1540 } 1541 } 1542 EXPORT_SYMBOL_GPL(sk_setup_caps); 1543 1544 /* 1545 * Simple resource managers for sockets. 1546 */ 1547 1548 1549 /* 1550 * Write buffer destructor automatically called from kfree_skb. 1551 */ 1552 void sock_wfree(struct sk_buff *skb) 1553 { 1554 struct sock *sk = skb->sk; 1555 unsigned int len = skb->truesize; 1556 1557 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1558 /* 1559 * Keep a reference on sk_wmem_alloc, this will be released 1560 * after sk_write_space() call 1561 */ 1562 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1563 sk->sk_write_space(sk); 1564 len = 1; 1565 } 1566 /* 1567 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1568 * could not do because of in-flight packets 1569 */ 1570 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1571 __sk_free(sk); 1572 } 1573 EXPORT_SYMBOL(sock_wfree); 1574 1575 void skb_orphan_partial(struct sk_buff *skb) 1576 { 1577 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc, 1578 * so we do not completely orphan skb, but transfert all 1579 * accounted bytes but one, to avoid unexpected reorders. 1580 */ 1581 if (skb->destructor == sock_wfree 1582 #ifdef CONFIG_INET 1583 || skb->destructor == tcp_wfree 1584 #endif 1585 ) { 1586 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc); 1587 skb->truesize = 1; 1588 } else { 1589 skb_orphan(skb); 1590 } 1591 } 1592 EXPORT_SYMBOL(skb_orphan_partial); 1593 1594 /* 1595 * Read buffer destructor automatically called from kfree_skb. 1596 */ 1597 void sock_rfree(struct sk_buff *skb) 1598 { 1599 struct sock *sk = skb->sk; 1600 unsigned int len = skb->truesize; 1601 1602 atomic_sub(len, &sk->sk_rmem_alloc); 1603 sk_mem_uncharge(sk, len); 1604 } 1605 EXPORT_SYMBOL(sock_rfree); 1606 1607 void sock_edemux(struct sk_buff *skb) 1608 { 1609 struct sock *sk = skb->sk; 1610 1611 #ifdef CONFIG_INET 1612 if (sk->sk_state == TCP_TIME_WAIT) 1613 inet_twsk_put(inet_twsk(sk)); 1614 else 1615 #endif 1616 sock_put(sk); 1617 } 1618 EXPORT_SYMBOL(sock_edemux); 1619 1620 kuid_t sock_i_uid(struct sock *sk) 1621 { 1622 kuid_t uid; 1623 1624 read_lock_bh(&sk->sk_callback_lock); 1625 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1626 read_unlock_bh(&sk->sk_callback_lock); 1627 return uid; 1628 } 1629 EXPORT_SYMBOL(sock_i_uid); 1630 1631 unsigned long sock_i_ino(struct sock *sk) 1632 { 1633 unsigned long ino; 1634 1635 read_lock_bh(&sk->sk_callback_lock); 1636 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1637 read_unlock_bh(&sk->sk_callback_lock); 1638 return ino; 1639 } 1640 EXPORT_SYMBOL(sock_i_ino); 1641 1642 /* 1643 * Allocate a skb from the socket's send buffer. 1644 */ 1645 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1646 gfp_t priority) 1647 { 1648 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1649 struct sk_buff *skb = alloc_skb(size, priority); 1650 if (skb) { 1651 skb_set_owner_w(skb, sk); 1652 return skb; 1653 } 1654 } 1655 return NULL; 1656 } 1657 EXPORT_SYMBOL(sock_wmalloc); 1658 1659 /* 1660 * Allocate a memory block from the socket's option memory buffer. 1661 */ 1662 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1663 { 1664 if ((unsigned int)size <= sysctl_optmem_max && 1665 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1666 void *mem; 1667 /* First do the add, to avoid the race if kmalloc 1668 * might sleep. 1669 */ 1670 atomic_add(size, &sk->sk_omem_alloc); 1671 mem = kmalloc(size, priority); 1672 if (mem) 1673 return mem; 1674 atomic_sub(size, &sk->sk_omem_alloc); 1675 } 1676 return NULL; 1677 } 1678 EXPORT_SYMBOL(sock_kmalloc); 1679 1680 /* 1681 * Free an option memory block. 1682 */ 1683 void sock_kfree_s(struct sock *sk, void *mem, int size) 1684 { 1685 kfree(mem); 1686 atomic_sub(size, &sk->sk_omem_alloc); 1687 } 1688 EXPORT_SYMBOL(sock_kfree_s); 1689 1690 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1691 I think, these locks should be removed for datagram sockets. 1692 */ 1693 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1694 { 1695 DEFINE_WAIT(wait); 1696 1697 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1698 for (;;) { 1699 if (!timeo) 1700 break; 1701 if (signal_pending(current)) 1702 break; 1703 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1704 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1705 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1706 break; 1707 if (sk->sk_shutdown & SEND_SHUTDOWN) 1708 break; 1709 if (sk->sk_err) 1710 break; 1711 timeo = schedule_timeout(timeo); 1712 } 1713 finish_wait(sk_sleep(sk), &wait); 1714 return timeo; 1715 } 1716 1717 1718 /* 1719 * Generic send/receive buffer handlers 1720 */ 1721 1722 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1723 unsigned long data_len, int noblock, 1724 int *errcode, int max_page_order) 1725 { 1726 struct sk_buff *skb = NULL; 1727 unsigned long chunk; 1728 gfp_t gfp_mask; 1729 long timeo; 1730 int err; 1731 int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT; 1732 struct page *page; 1733 int i; 1734 1735 err = -EMSGSIZE; 1736 if (npages > MAX_SKB_FRAGS) 1737 goto failure; 1738 1739 timeo = sock_sndtimeo(sk, noblock); 1740 while (!skb) { 1741 err = sock_error(sk); 1742 if (err != 0) 1743 goto failure; 1744 1745 err = -EPIPE; 1746 if (sk->sk_shutdown & SEND_SHUTDOWN) 1747 goto failure; 1748 1749 if (atomic_read(&sk->sk_wmem_alloc) >= sk->sk_sndbuf) { 1750 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1751 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1752 err = -EAGAIN; 1753 if (!timeo) 1754 goto failure; 1755 if (signal_pending(current)) 1756 goto interrupted; 1757 timeo = sock_wait_for_wmem(sk, timeo); 1758 continue; 1759 } 1760 1761 err = -ENOBUFS; 1762 gfp_mask = sk->sk_allocation; 1763 if (gfp_mask & __GFP_WAIT) 1764 gfp_mask |= __GFP_REPEAT; 1765 1766 skb = alloc_skb(header_len, gfp_mask); 1767 if (!skb) 1768 goto failure; 1769 1770 skb->truesize += data_len; 1771 1772 for (i = 0; npages > 0; i++) { 1773 int order = max_page_order; 1774 1775 while (order) { 1776 if (npages >= 1 << order) { 1777 page = alloc_pages(sk->sk_allocation | 1778 __GFP_COMP | __GFP_NOWARN, 1779 order); 1780 if (page) 1781 goto fill_page; 1782 } 1783 order--; 1784 } 1785 page = alloc_page(sk->sk_allocation); 1786 if (!page) 1787 goto failure; 1788 fill_page: 1789 chunk = min_t(unsigned long, data_len, 1790 PAGE_SIZE << order); 1791 skb_fill_page_desc(skb, i, page, 0, chunk); 1792 data_len -= chunk; 1793 npages -= 1 << order; 1794 } 1795 } 1796 1797 skb_set_owner_w(skb, sk); 1798 return skb; 1799 1800 interrupted: 1801 err = sock_intr_errno(timeo); 1802 failure: 1803 kfree_skb(skb); 1804 *errcode = err; 1805 return NULL; 1806 } 1807 EXPORT_SYMBOL(sock_alloc_send_pskb); 1808 1809 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1810 int noblock, int *errcode) 1811 { 1812 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1813 } 1814 EXPORT_SYMBOL(sock_alloc_send_skb); 1815 1816 /* On 32bit arches, an skb frag is limited to 2^15 */ 1817 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1818 1819 /** 1820 * skb_page_frag_refill - check that a page_frag contains enough room 1821 * @sz: minimum size of the fragment we want to get 1822 * @pfrag: pointer to page_frag 1823 * @prio: priority for memory allocation 1824 * 1825 * Note: While this allocator tries to use high order pages, there is 1826 * no guarantee that allocations succeed. Therefore, @sz MUST be 1827 * less or equal than PAGE_SIZE. 1828 */ 1829 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t prio) 1830 { 1831 int order; 1832 1833 if (pfrag->page) { 1834 if (atomic_read(&pfrag->page->_count) == 1) { 1835 pfrag->offset = 0; 1836 return true; 1837 } 1838 if (pfrag->offset + sz <= pfrag->size) 1839 return true; 1840 put_page(pfrag->page); 1841 } 1842 1843 order = SKB_FRAG_PAGE_ORDER; 1844 do { 1845 gfp_t gfp = prio; 1846 1847 if (order) 1848 gfp |= __GFP_COMP | __GFP_NOWARN; 1849 pfrag->page = alloc_pages(gfp, order); 1850 if (likely(pfrag->page)) { 1851 pfrag->offset = 0; 1852 pfrag->size = PAGE_SIZE << order; 1853 return true; 1854 } 1855 } while (--order >= 0); 1856 1857 return false; 1858 } 1859 EXPORT_SYMBOL(skb_page_frag_refill); 1860 1861 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 1862 { 1863 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 1864 return true; 1865 1866 sk_enter_memory_pressure(sk); 1867 sk_stream_moderate_sndbuf(sk); 1868 return false; 1869 } 1870 EXPORT_SYMBOL(sk_page_frag_refill); 1871 1872 static void __lock_sock(struct sock *sk) 1873 __releases(&sk->sk_lock.slock) 1874 __acquires(&sk->sk_lock.slock) 1875 { 1876 DEFINE_WAIT(wait); 1877 1878 for (;;) { 1879 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 1880 TASK_UNINTERRUPTIBLE); 1881 spin_unlock_bh(&sk->sk_lock.slock); 1882 schedule(); 1883 spin_lock_bh(&sk->sk_lock.slock); 1884 if (!sock_owned_by_user(sk)) 1885 break; 1886 } 1887 finish_wait(&sk->sk_lock.wq, &wait); 1888 } 1889 1890 static void __release_sock(struct sock *sk) 1891 __releases(&sk->sk_lock.slock) 1892 __acquires(&sk->sk_lock.slock) 1893 { 1894 struct sk_buff *skb = sk->sk_backlog.head; 1895 1896 do { 1897 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 1898 bh_unlock_sock(sk); 1899 1900 do { 1901 struct sk_buff *next = skb->next; 1902 1903 prefetch(next); 1904 WARN_ON_ONCE(skb_dst_is_noref(skb)); 1905 skb->next = NULL; 1906 sk_backlog_rcv(sk, skb); 1907 1908 /* 1909 * We are in process context here with softirqs 1910 * disabled, use cond_resched_softirq() to preempt. 1911 * This is safe to do because we've taken the backlog 1912 * queue private: 1913 */ 1914 cond_resched_softirq(); 1915 1916 skb = next; 1917 } while (skb != NULL); 1918 1919 bh_lock_sock(sk); 1920 } while ((skb = sk->sk_backlog.head) != NULL); 1921 1922 /* 1923 * Doing the zeroing here guarantee we can not loop forever 1924 * while a wild producer attempts to flood us. 1925 */ 1926 sk->sk_backlog.len = 0; 1927 } 1928 1929 /** 1930 * sk_wait_data - wait for data to arrive at sk_receive_queue 1931 * @sk: sock to wait on 1932 * @timeo: for how long 1933 * 1934 * Now socket state including sk->sk_err is changed only under lock, 1935 * hence we may omit checks after joining wait queue. 1936 * We check receive queue before schedule() only as optimization; 1937 * it is very likely that release_sock() added new data. 1938 */ 1939 int sk_wait_data(struct sock *sk, long *timeo) 1940 { 1941 int rc; 1942 DEFINE_WAIT(wait); 1943 1944 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1945 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1946 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); 1947 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1948 finish_wait(sk_sleep(sk), &wait); 1949 return rc; 1950 } 1951 EXPORT_SYMBOL(sk_wait_data); 1952 1953 /** 1954 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 1955 * @sk: socket 1956 * @size: memory size to allocate 1957 * @kind: allocation type 1958 * 1959 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 1960 * rmem allocation. This function assumes that protocols which have 1961 * memory_pressure use sk_wmem_queued as write buffer accounting. 1962 */ 1963 int __sk_mem_schedule(struct sock *sk, int size, int kind) 1964 { 1965 struct proto *prot = sk->sk_prot; 1966 int amt = sk_mem_pages(size); 1967 long allocated; 1968 int parent_status = UNDER_LIMIT; 1969 1970 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; 1971 1972 allocated = sk_memory_allocated_add(sk, amt, &parent_status); 1973 1974 /* Under limit. */ 1975 if (parent_status == UNDER_LIMIT && 1976 allocated <= sk_prot_mem_limits(sk, 0)) { 1977 sk_leave_memory_pressure(sk); 1978 return 1; 1979 } 1980 1981 /* Under pressure. (we or our parents) */ 1982 if ((parent_status > SOFT_LIMIT) || 1983 allocated > sk_prot_mem_limits(sk, 1)) 1984 sk_enter_memory_pressure(sk); 1985 1986 /* Over hard limit (we or our parents) */ 1987 if ((parent_status == OVER_LIMIT) || 1988 (allocated > sk_prot_mem_limits(sk, 2))) 1989 goto suppress_allocation; 1990 1991 /* guarantee minimum buffer size under pressure */ 1992 if (kind == SK_MEM_RECV) { 1993 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 1994 return 1; 1995 1996 } else { /* SK_MEM_SEND */ 1997 if (sk->sk_type == SOCK_STREAM) { 1998 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 1999 return 1; 2000 } else if (atomic_read(&sk->sk_wmem_alloc) < 2001 prot->sysctl_wmem[0]) 2002 return 1; 2003 } 2004 2005 if (sk_has_memory_pressure(sk)) { 2006 int alloc; 2007 2008 if (!sk_under_memory_pressure(sk)) 2009 return 1; 2010 alloc = sk_sockets_allocated_read_positive(sk); 2011 if (sk_prot_mem_limits(sk, 2) > alloc * 2012 sk_mem_pages(sk->sk_wmem_queued + 2013 atomic_read(&sk->sk_rmem_alloc) + 2014 sk->sk_forward_alloc)) 2015 return 1; 2016 } 2017 2018 suppress_allocation: 2019 2020 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2021 sk_stream_moderate_sndbuf(sk); 2022 2023 /* Fail only if socket is _under_ its sndbuf. 2024 * In this case we cannot block, so that we have to fail. 2025 */ 2026 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2027 return 1; 2028 } 2029 2030 trace_sock_exceed_buf_limit(sk, prot, allocated); 2031 2032 /* Alas. Undo changes. */ 2033 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM; 2034 2035 sk_memory_allocated_sub(sk, amt); 2036 2037 return 0; 2038 } 2039 EXPORT_SYMBOL(__sk_mem_schedule); 2040 2041 /** 2042 * __sk_reclaim - reclaim memory_allocated 2043 * @sk: socket 2044 */ 2045 void __sk_mem_reclaim(struct sock *sk) 2046 { 2047 sk_memory_allocated_sub(sk, 2048 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT); 2049 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1; 2050 2051 if (sk_under_memory_pressure(sk) && 2052 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2053 sk_leave_memory_pressure(sk); 2054 } 2055 EXPORT_SYMBOL(__sk_mem_reclaim); 2056 2057 2058 /* 2059 * Set of default routines for initialising struct proto_ops when 2060 * the protocol does not support a particular function. In certain 2061 * cases where it makes no sense for a protocol to have a "do nothing" 2062 * function, some default processing is provided. 2063 */ 2064 2065 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2066 { 2067 return -EOPNOTSUPP; 2068 } 2069 EXPORT_SYMBOL(sock_no_bind); 2070 2071 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2072 int len, int flags) 2073 { 2074 return -EOPNOTSUPP; 2075 } 2076 EXPORT_SYMBOL(sock_no_connect); 2077 2078 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2079 { 2080 return -EOPNOTSUPP; 2081 } 2082 EXPORT_SYMBOL(sock_no_socketpair); 2083 2084 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 2085 { 2086 return -EOPNOTSUPP; 2087 } 2088 EXPORT_SYMBOL(sock_no_accept); 2089 2090 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2091 int *len, int peer) 2092 { 2093 return -EOPNOTSUPP; 2094 } 2095 EXPORT_SYMBOL(sock_no_getname); 2096 2097 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 2098 { 2099 return 0; 2100 } 2101 EXPORT_SYMBOL(sock_no_poll); 2102 2103 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2104 { 2105 return -EOPNOTSUPP; 2106 } 2107 EXPORT_SYMBOL(sock_no_ioctl); 2108 2109 int sock_no_listen(struct socket *sock, int backlog) 2110 { 2111 return -EOPNOTSUPP; 2112 } 2113 EXPORT_SYMBOL(sock_no_listen); 2114 2115 int sock_no_shutdown(struct socket *sock, int how) 2116 { 2117 return -EOPNOTSUPP; 2118 } 2119 EXPORT_SYMBOL(sock_no_shutdown); 2120 2121 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2122 char __user *optval, unsigned int optlen) 2123 { 2124 return -EOPNOTSUPP; 2125 } 2126 EXPORT_SYMBOL(sock_no_setsockopt); 2127 2128 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2129 char __user *optval, int __user *optlen) 2130 { 2131 return -EOPNOTSUPP; 2132 } 2133 EXPORT_SYMBOL(sock_no_getsockopt); 2134 2135 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2136 size_t len) 2137 { 2138 return -EOPNOTSUPP; 2139 } 2140 EXPORT_SYMBOL(sock_no_sendmsg); 2141 2142 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2143 size_t len, int flags) 2144 { 2145 return -EOPNOTSUPP; 2146 } 2147 EXPORT_SYMBOL(sock_no_recvmsg); 2148 2149 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2150 { 2151 /* Mirror missing mmap method error code */ 2152 return -ENODEV; 2153 } 2154 EXPORT_SYMBOL(sock_no_mmap); 2155 2156 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2157 { 2158 ssize_t res; 2159 struct msghdr msg = {.msg_flags = flags}; 2160 struct kvec iov; 2161 char *kaddr = kmap(page); 2162 iov.iov_base = kaddr + offset; 2163 iov.iov_len = size; 2164 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2165 kunmap(page); 2166 return res; 2167 } 2168 EXPORT_SYMBOL(sock_no_sendpage); 2169 2170 /* 2171 * Default Socket Callbacks 2172 */ 2173 2174 static void sock_def_wakeup(struct sock *sk) 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_all(&wq->wait); 2182 rcu_read_unlock(); 2183 } 2184 2185 static void sock_def_error_report(struct sock *sk) 2186 { 2187 struct socket_wq *wq; 2188 2189 rcu_read_lock(); 2190 wq = rcu_dereference(sk->sk_wq); 2191 if (wq_has_sleeper(wq)) 2192 wake_up_interruptible_poll(&wq->wait, POLLERR); 2193 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2194 rcu_read_unlock(); 2195 } 2196 2197 static void sock_def_readable(struct sock *sk, int len) 2198 { 2199 struct socket_wq *wq; 2200 2201 rcu_read_lock(); 2202 wq = rcu_dereference(sk->sk_wq); 2203 if (wq_has_sleeper(wq)) 2204 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI | 2205 POLLRDNORM | POLLRDBAND); 2206 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2207 rcu_read_unlock(); 2208 } 2209 2210 static void sock_def_write_space(struct sock *sk) 2211 { 2212 struct socket_wq *wq; 2213 2214 rcu_read_lock(); 2215 2216 /* Do not wake up a writer until he can make "significant" 2217 * progress. --DaveM 2218 */ 2219 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2220 wq = rcu_dereference(sk->sk_wq); 2221 if (wq_has_sleeper(wq)) 2222 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 2223 POLLWRNORM | POLLWRBAND); 2224 2225 /* Should agree with poll, otherwise some programs break */ 2226 if (sock_writeable(sk)) 2227 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2228 } 2229 2230 rcu_read_unlock(); 2231 } 2232 2233 static void sock_def_destruct(struct sock *sk) 2234 { 2235 kfree(sk->sk_protinfo); 2236 } 2237 2238 void sk_send_sigurg(struct sock *sk) 2239 { 2240 if (sk->sk_socket && sk->sk_socket->file) 2241 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2242 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2243 } 2244 EXPORT_SYMBOL(sk_send_sigurg); 2245 2246 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2247 unsigned long expires) 2248 { 2249 if (!mod_timer(timer, expires)) 2250 sock_hold(sk); 2251 } 2252 EXPORT_SYMBOL(sk_reset_timer); 2253 2254 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2255 { 2256 if (del_timer(timer)) 2257 __sock_put(sk); 2258 } 2259 EXPORT_SYMBOL(sk_stop_timer); 2260 2261 void sock_init_data(struct socket *sock, struct sock *sk) 2262 { 2263 skb_queue_head_init(&sk->sk_receive_queue); 2264 skb_queue_head_init(&sk->sk_write_queue); 2265 skb_queue_head_init(&sk->sk_error_queue); 2266 #ifdef CONFIG_NET_DMA 2267 skb_queue_head_init(&sk->sk_async_wait_queue); 2268 #endif 2269 2270 sk->sk_send_head = NULL; 2271 2272 init_timer(&sk->sk_timer); 2273 2274 sk->sk_allocation = GFP_KERNEL; 2275 sk->sk_rcvbuf = sysctl_rmem_default; 2276 sk->sk_sndbuf = sysctl_wmem_default; 2277 sk->sk_state = TCP_CLOSE; 2278 sk_set_socket(sk, sock); 2279 2280 sock_set_flag(sk, SOCK_ZAPPED); 2281 2282 if (sock) { 2283 sk->sk_type = sock->type; 2284 sk->sk_wq = sock->wq; 2285 sock->sk = sk; 2286 } else 2287 sk->sk_wq = NULL; 2288 2289 spin_lock_init(&sk->sk_dst_lock); 2290 rwlock_init(&sk->sk_callback_lock); 2291 lockdep_set_class_and_name(&sk->sk_callback_lock, 2292 af_callback_keys + sk->sk_family, 2293 af_family_clock_key_strings[sk->sk_family]); 2294 2295 sk->sk_state_change = sock_def_wakeup; 2296 sk->sk_data_ready = sock_def_readable; 2297 sk->sk_write_space = sock_def_write_space; 2298 sk->sk_error_report = sock_def_error_report; 2299 sk->sk_destruct = sock_def_destruct; 2300 2301 sk->sk_frag.page = NULL; 2302 sk->sk_frag.offset = 0; 2303 sk->sk_peek_off = -1; 2304 2305 sk->sk_peer_pid = NULL; 2306 sk->sk_peer_cred = NULL; 2307 sk->sk_write_pending = 0; 2308 sk->sk_rcvlowat = 1; 2309 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2310 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2311 2312 sk->sk_stamp = ktime_set(-1L, 0); 2313 2314 #ifdef CONFIG_NET_RX_BUSY_POLL 2315 sk->sk_napi_id = 0; 2316 sk->sk_ll_usec = sysctl_net_busy_read; 2317 #endif 2318 2319 sk->sk_max_pacing_rate = ~0U; 2320 sk->sk_pacing_rate = ~0U; 2321 /* 2322 * Before updating sk_refcnt, we must commit prior changes to memory 2323 * (Documentation/RCU/rculist_nulls.txt for details) 2324 */ 2325 smp_wmb(); 2326 atomic_set(&sk->sk_refcnt, 1); 2327 atomic_set(&sk->sk_drops, 0); 2328 } 2329 EXPORT_SYMBOL(sock_init_data); 2330 2331 void lock_sock_nested(struct sock *sk, int subclass) 2332 { 2333 might_sleep(); 2334 spin_lock_bh(&sk->sk_lock.slock); 2335 if (sk->sk_lock.owned) 2336 __lock_sock(sk); 2337 sk->sk_lock.owned = 1; 2338 spin_unlock(&sk->sk_lock.slock); 2339 /* 2340 * The sk_lock has mutex_lock() semantics here: 2341 */ 2342 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2343 local_bh_enable(); 2344 } 2345 EXPORT_SYMBOL(lock_sock_nested); 2346 2347 void release_sock(struct sock *sk) 2348 { 2349 /* 2350 * The sk_lock has mutex_unlock() semantics: 2351 */ 2352 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 2353 2354 spin_lock_bh(&sk->sk_lock.slock); 2355 if (sk->sk_backlog.tail) 2356 __release_sock(sk); 2357 2358 if (sk->sk_prot->release_cb) 2359 sk->sk_prot->release_cb(sk); 2360 2361 sk->sk_lock.owned = 0; 2362 if (waitqueue_active(&sk->sk_lock.wq)) 2363 wake_up(&sk->sk_lock.wq); 2364 spin_unlock_bh(&sk->sk_lock.slock); 2365 } 2366 EXPORT_SYMBOL(release_sock); 2367 2368 /** 2369 * lock_sock_fast - fast version of lock_sock 2370 * @sk: socket 2371 * 2372 * This version should be used for very small section, where process wont block 2373 * return false if fast path is taken 2374 * sk_lock.slock locked, owned = 0, BH disabled 2375 * return true if slow path is taken 2376 * sk_lock.slock unlocked, owned = 1, BH enabled 2377 */ 2378 bool lock_sock_fast(struct sock *sk) 2379 { 2380 might_sleep(); 2381 spin_lock_bh(&sk->sk_lock.slock); 2382 2383 if (!sk->sk_lock.owned) 2384 /* 2385 * Note : We must disable BH 2386 */ 2387 return false; 2388 2389 __lock_sock(sk); 2390 sk->sk_lock.owned = 1; 2391 spin_unlock(&sk->sk_lock.slock); 2392 /* 2393 * The sk_lock has mutex_lock() semantics here: 2394 */ 2395 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2396 local_bh_enable(); 2397 return true; 2398 } 2399 EXPORT_SYMBOL(lock_sock_fast); 2400 2401 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2402 { 2403 struct timeval tv; 2404 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2405 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2406 tv = ktime_to_timeval(sk->sk_stamp); 2407 if (tv.tv_sec == -1) 2408 return -ENOENT; 2409 if (tv.tv_sec == 0) { 2410 sk->sk_stamp = ktime_get_real(); 2411 tv = ktime_to_timeval(sk->sk_stamp); 2412 } 2413 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2414 } 2415 EXPORT_SYMBOL(sock_get_timestamp); 2416 2417 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2418 { 2419 struct timespec ts; 2420 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2421 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2422 ts = ktime_to_timespec(sk->sk_stamp); 2423 if (ts.tv_sec == -1) 2424 return -ENOENT; 2425 if (ts.tv_sec == 0) { 2426 sk->sk_stamp = ktime_get_real(); 2427 ts = ktime_to_timespec(sk->sk_stamp); 2428 } 2429 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2430 } 2431 EXPORT_SYMBOL(sock_get_timestampns); 2432 2433 void sock_enable_timestamp(struct sock *sk, int flag) 2434 { 2435 if (!sock_flag(sk, flag)) { 2436 unsigned long previous_flags = sk->sk_flags; 2437 2438 sock_set_flag(sk, flag); 2439 /* 2440 * we just set one of the two flags which require net 2441 * time stamping, but time stamping might have been on 2442 * already because of the other one 2443 */ 2444 if (!(previous_flags & SK_FLAGS_TIMESTAMP)) 2445 net_enable_timestamp(); 2446 } 2447 } 2448 2449 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 2450 int level, int type) 2451 { 2452 struct sock_exterr_skb *serr; 2453 struct sk_buff *skb, *skb2; 2454 int copied, err; 2455 2456 err = -EAGAIN; 2457 skb = skb_dequeue(&sk->sk_error_queue); 2458 if (skb == NULL) 2459 goto out; 2460 2461 copied = skb->len; 2462 if (copied > len) { 2463 msg->msg_flags |= MSG_TRUNC; 2464 copied = len; 2465 } 2466 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 2467 if (err) 2468 goto out_free_skb; 2469 2470 sock_recv_timestamp(msg, sk, skb); 2471 2472 serr = SKB_EXT_ERR(skb); 2473 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 2474 2475 msg->msg_flags |= MSG_ERRQUEUE; 2476 err = copied; 2477 2478 /* Reset and regenerate socket error */ 2479 spin_lock_bh(&sk->sk_error_queue.lock); 2480 sk->sk_err = 0; 2481 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) { 2482 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno; 2483 spin_unlock_bh(&sk->sk_error_queue.lock); 2484 sk->sk_error_report(sk); 2485 } else 2486 spin_unlock_bh(&sk->sk_error_queue.lock); 2487 2488 out_free_skb: 2489 kfree_skb(skb); 2490 out: 2491 return err; 2492 } 2493 EXPORT_SYMBOL(sock_recv_errqueue); 2494 2495 /* 2496 * Get a socket option on an socket. 2497 * 2498 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2499 * asynchronous errors should be reported by getsockopt. We assume 2500 * this means if you specify SO_ERROR (otherwise whats the point of it). 2501 */ 2502 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2503 char __user *optval, int __user *optlen) 2504 { 2505 struct sock *sk = sock->sk; 2506 2507 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2508 } 2509 EXPORT_SYMBOL(sock_common_getsockopt); 2510 2511 #ifdef CONFIG_COMPAT 2512 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2513 char __user *optval, int __user *optlen) 2514 { 2515 struct sock *sk = sock->sk; 2516 2517 if (sk->sk_prot->compat_getsockopt != NULL) 2518 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2519 optval, optlen); 2520 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2521 } 2522 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2523 #endif 2524 2525 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, 2526 struct msghdr *msg, size_t size, int flags) 2527 { 2528 struct sock *sk = sock->sk; 2529 int addr_len = 0; 2530 int err; 2531 2532 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT, 2533 flags & ~MSG_DONTWAIT, &addr_len); 2534 if (err >= 0) 2535 msg->msg_namelen = addr_len; 2536 return err; 2537 } 2538 EXPORT_SYMBOL(sock_common_recvmsg); 2539 2540 /* 2541 * Set socket options on an inet socket. 2542 */ 2543 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2544 char __user *optval, unsigned int optlen) 2545 { 2546 struct sock *sk = sock->sk; 2547 2548 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2549 } 2550 EXPORT_SYMBOL(sock_common_setsockopt); 2551 2552 #ifdef CONFIG_COMPAT 2553 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2554 char __user *optval, unsigned int optlen) 2555 { 2556 struct sock *sk = sock->sk; 2557 2558 if (sk->sk_prot->compat_setsockopt != NULL) 2559 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2560 optval, optlen); 2561 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2562 } 2563 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2564 #endif 2565 2566 void sk_common_release(struct sock *sk) 2567 { 2568 if (sk->sk_prot->destroy) 2569 sk->sk_prot->destroy(sk); 2570 2571 /* 2572 * Observation: when sock_common_release is called, processes have 2573 * no access to socket. But net still has. 2574 * Step one, detach it from networking: 2575 * 2576 * A. Remove from hash tables. 2577 */ 2578 2579 sk->sk_prot->unhash(sk); 2580 2581 /* 2582 * In this point socket cannot receive new packets, but it is possible 2583 * that some packets are in flight because some CPU runs receiver and 2584 * did hash table lookup before we unhashed socket. They will achieve 2585 * receive queue and will be purged by socket destructor. 2586 * 2587 * Also we still have packets pending on receive queue and probably, 2588 * our own packets waiting in device queues. sock_destroy will drain 2589 * receive queue, but transmitted packets will delay socket destruction 2590 * until the last reference will be released. 2591 */ 2592 2593 sock_orphan(sk); 2594 2595 xfrm_sk_free_policy(sk); 2596 2597 sk_refcnt_debug_release(sk); 2598 2599 if (sk->sk_frag.page) { 2600 put_page(sk->sk_frag.page); 2601 sk->sk_frag.page = NULL; 2602 } 2603 2604 sock_put(sk); 2605 } 2606 EXPORT_SYMBOL(sk_common_release); 2607 2608 #ifdef CONFIG_PROC_FS 2609 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2610 struct prot_inuse { 2611 int val[PROTO_INUSE_NR]; 2612 }; 2613 2614 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2615 2616 #ifdef CONFIG_NET_NS 2617 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2618 { 2619 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2620 } 2621 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2622 2623 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2624 { 2625 int cpu, idx = prot->inuse_idx; 2626 int res = 0; 2627 2628 for_each_possible_cpu(cpu) 2629 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2630 2631 return res >= 0 ? res : 0; 2632 } 2633 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2634 2635 static int __net_init sock_inuse_init_net(struct net *net) 2636 { 2637 net->core.inuse = alloc_percpu(struct prot_inuse); 2638 return net->core.inuse ? 0 : -ENOMEM; 2639 } 2640 2641 static void __net_exit sock_inuse_exit_net(struct net *net) 2642 { 2643 free_percpu(net->core.inuse); 2644 } 2645 2646 static struct pernet_operations net_inuse_ops = { 2647 .init = sock_inuse_init_net, 2648 .exit = sock_inuse_exit_net, 2649 }; 2650 2651 static __init int net_inuse_init(void) 2652 { 2653 if (register_pernet_subsys(&net_inuse_ops)) 2654 panic("Cannot initialize net inuse counters"); 2655 2656 return 0; 2657 } 2658 2659 core_initcall(net_inuse_init); 2660 #else 2661 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2662 2663 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2664 { 2665 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2666 } 2667 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2668 2669 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2670 { 2671 int cpu, idx = prot->inuse_idx; 2672 int res = 0; 2673 2674 for_each_possible_cpu(cpu) 2675 res += per_cpu(prot_inuse, cpu).val[idx]; 2676 2677 return res >= 0 ? res : 0; 2678 } 2679 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2680 #endif 2681 2682 static void assign_proto_idx(struct proto *prot) 2683 { 2684 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2685 2686 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2687 pr_err("PROTO_INUSE_NR exhausted\n"); 2688 return; 2689 } 2690 2691 set_bit(prot->inuse_idx, proto_inuse_idx); 2692 } 2693 2694 static void release_proto_idx(struct proto *prot) 2695 { 2696 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2697 clear_bit(prot->inuse_idx, proto_inuse_idx); 2698 } 2699 #else 2700 static inline void assign_proto_idx(struct proto *prot) 2701 { 2702 } 2703 2704 static inline void release_proto_idx(struct proto *prot) 2705 { 2706 } 2707 #endif 2708 2709 int proto_register(struct proto *prot, int alloc_slab) 2710 { 2711 if (alloc_slab) { 2712 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2713 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2714 NULL); 2715 2716 if (prot->slab == NULL) { 2717 pr_crit("%s: Can't create sock SLAB cache!\n", 2718 prot->name); 2719 goto out; 2720 } 2721 2722 if (prot->rsk_prot != NULL) { 2723 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name); 2724 if (prot->rsk_prot->slab_name == NULL) 2725 goto out_free_sock_slab; 2726 2727 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name, 2728 prot->rsk_prot->obj_size, 0, 2729 SLAB_HWCACHE_ALIGN, NULL); 2730 2731 if (prot->rsk_prot->slab == NULL) { 2732 pr_crit("%s: Can't create request sock SLAB cache!\n", 2733 prot->name); 2734 goto out_free_request_sock_slab_name; 2735 } 2736 } 2737 2738 if (prot->twsk_prot != NULL) { 2739 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2740 2741 if (prot->twsk_prot->twsk_slab_name == NULL) 2742 goto out_free_request_sock_slab; 2743 2744 prot->twsk_prot->twsk_slab = 2745 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2746 prot->twsk_prot->twsk_obj_size, 2747 0, 2748 SLAB_HWCACHE_ALIGN | 2749 prot->slab_flags, 2750 NULL); 2751 if (prot->twsk_prot->twsk_slab == NULL) 2752 goto out_free_timewait_sock_slab_name; 2753 } 2754 } 2755 2756 mutex_lock(&proto_list_mutex); 2757 list_add(&prot->node, &proto_list); 2758 assign_proto_idx(prot); 2759 mutex_unlock(&proto_list_mutex); 2760 return 0; 2761 2762 out_free_timewait_sock_slab_name: 2763 kfree(prot->twsk_prot->twsk_slab_name); 2764 out_free_request_sock_slab: 2765 if (prot->rsk_prot && prot->rsk_prot->slab) { 2766 kmem_cache_destroy(prot->rsk_prot->slab); 2767 prot->rsk_prot->slab = NULL; 2768 } 2769 out_free_request_sock_slab_name: 2770 if (prot->rsk_prot) 2771 kfree(prot->rsk_prot->slab_name); 2772 out_free_sock_slab: 2773 kmem_cache_destroy(prot->slab); 2774 prot->slab = NULL; 2775 out: 2776 return -ENOBUFS; 2777 } 2778 EXPORT_SYMBOL(proto_register); 2779 2780 void proto_unregister(struct proto *prot) 2781 { 2782 mutex_lock(&proto_list_mutex); 2783 release_proto_idx(prot); 2784 list_del(&prot->node); 2785 mutex_unlock(&proto_list_mutex); 2786 2787 if (prot->slab != NULL) { 2788 kmem_cache_destroy(prot->slab); 2789 prot->slab = NULL; 2790 } 2791 2792 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) { 2793 kmem_cache_destroy(prot->rsk_prot->slab); 2794 kfree(prot->rsk_prot->slab_name); 2795 prot->rsk_prot->slab = NULL; 2796 } 2797 2798 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2799 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2800 kfree(prot->twsk_prot->twsk_slab_name); 2801 prot->twsk_prot->twsk_slab = NULL; 2802 } 2803 } 2804 EXPORT_SYMBOL(proto_unregister); 2805 2806 #ifdef CONFIG_PROC_FS 2807 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2808 __acquires(proto_list_mutex) 2809 { 2810 mutex_lock(&proto_list_mutex); 2811 return seq_list_start_head(&proto_list, *pos); 2812 } 2813 2814 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2815 { 2816 return seq_list_next(v, &proto_list, pos); 2817 } 2818 2819 static void proto_seq_stop(struct seq_file *seq, void *v) 2820 __releases(proto_list_mutex) 2821 { 2822 mutex_unlock(&proto_list_mutex); 2823 } 2824 2825 static char proto_method_implemented(const void *method) 2826 { 2827 return method == NULL ? 'n' : 'y'; 2828 } 2829 static long sock_prot_memory_allocated(struct proto *proto) 2830 { 2831 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 2832 } 2833 2834 static char *sock_prot_memory_pressure(struct proto *proto) 2835 { 2836 return proto->memory_pressure != NULL ? 2837 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 2838 } 2839 2840 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 2841 { 2842 2843 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 2844 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 2845 proto->name, 2846 proto->obj_size, 2847 sock_prot_inuse_get(seq_file_net(seq), proto), 2848 sock_prot_memory_allocated(proto), 2849 sock_prot_memory_pressure(proto), 2850 proto->max_header, 2851 proto->slab == NULL ? "no" : "yes", 2852 module_name(proto->owner), 2853 proto_method_implemented(proto->close), 2854 proto_method_implemented(proto->connect), 2855 proto_method_implemented(proto->disconnect), 2856 proto_method_implemented(proto->accept), 2857 proto_method_implemented(proto->ioctl), 2858 proto_method_implemented(proto->init), 2859 proto_method_implemented(proto->destroy), 2860 proto_method_implemented(proto->shutdown), 2861 proto_method_implemented(proto->setsockopt), 2862 proto_method_implemented(proto->getsockopt), 2863 proto_method_implemented(proto->sendmsg), 2864 proto_method_implemented(proto->recvmsg), 2865 proto_method_implemented(proto->sendpage), 2866 proto_method_implemented(proto->bind), 2867 proto_method_implemented(proto->backlog_rcv), 2868 proto_method_implemented(proto->hash), 2869 proto_method_implemented(proto->unhash), 2870 proto_method_implemented(proto->get_port), 2871 proto_method_implemented(proto->enter_memory_pressure)); 2872 } 2873 2874 static int proto_seq_show(struct seq_file *seq, void *v) 2875 { 2876 if (v == &proto_list) 2877 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 2878 "protocol", 2879 "size", 2880 "sockets", 2881 "memory", 2882 "press", 2883 "maxhdr", 2884 "slab", 2885 "module", 2886 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 2887 else 2888 proto_seq_printf(seq, list_entry(v, struct proto, node)); 2889 return 0; 2890 } 2891 2892 static const struct seq_operations proto_seq_ops = { 2893 .start = proto_seq_start, 2894 .next = proto_seq_next, 2895 .stop = proto_seq_stop, 2896 .show = proto_seq_show, 2897 }; 2898 2899 static int proto_seq_open(struct inode *inode, struct file *file) 2900 { 2901 return seq_open_net(inode, file, &proto_seq_ops, 2902 sizeof(struct seq_net_private)); 2903 } 2904 2905 static const struct file_operations proto_seq_fops = { 2906 .owner = THIS_MODULE, 2907 .open = proto_seq_open, 2908 .read = seq_read, 2909 .llseek = seq_lseek, 2910 .release = seq_release_net, 2911 }; 2912 2913 static __net_init int proto_init_net(struct net *net) 2914 { 2915 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops)) 2916 return -ENOMEM; 2917 2918 return 0; 2919 } 2920 2921 static __net_exit void proto_exit_net(struct net *net) 2922 { 2923 remove_proc_entry("protocols", net->proc_net); 2924 } 2925 2926 2927 static __net_initdata struct pernet_operations proto_net_ops = { 2928 .init = proto_init_net, 2929 .exit = proto_exit_net, 2930 }; 2931 2932 static int __init proto_init(void) 2933 { 2934 return register_pernet_subsys(&proto_net_ops); 2935 } 2936 2937 subsys_initcall(proto_init); 2938 2939 #endif /* PROC_FS */ 2940