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 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 EXPORT_SYMBOL_GPL(cred_to_ucred); 941 942 int sock_getsockopt(struct socket *sock, int level, int optname, 943 char __user *optval, int __user *optlen) 944 { 945 struct sock *sk = sock->sk; 946 947 union { 948 int val; 949 struct linger ling; 950 struct timeval tm; 951 } v; 952 953 int lv = sizeof(int); 954 int len; 955 956 if (get_user(len, optlen)) 957 return -EFAULT; 958 if (len < 0) 959 return -EINVAL; 960 961 memset(&v, 0, sizeof(v)); 962 963 switch (optname) { 964 case SO_DEBUG: 965 v.val = sock_flag(sk, SOCK_DBG); 966 break; 967 968 case SO_DONTROUTE: 969 v.val = sock_flag(sk, SOCK_LOCALROUTE); 970 break; 971 972 case SO_BROADCAST: 973 v.val = sock_flag(sk, SOCK_BROADCAST); 974 break; 975 976 case SO_SNDBUF: 977 v.val = sk->sk_sndbuf; 978 break; 979 980 case SO_RCVBUF: 981 v.val = sk->sk_rcvbuf; 982 break; 983 984 case SO_REUSEADDR: 985 v.val = sk->sk_reuse; 986 break; 987 988 case SO_REUSEPORT: 989 v.val = sk->sk_reuseport; 990 break; 991 992 case SO_KEEPALIVE: 993 v.val = sock_flag(sk, SOCK_KEEPOPEN); 994 break; 995 996 case SO_TYPE: 997 v.val = sk->sk_type; 998 break; 999 1000 case SO_PROTOCOL: 1001 v.val = sk->sk_protocol; 1002 break; 1003 1004 case SO_DOMAIN: 1005 v.val = sk->sk_family; 1006 break; 1007 1008 case SO_ERROR: 1009 v.val = -sock_error(sk); 1010 if (v.val == 0) 1011 v.val = xchg(&sk->sk_err_soft, 0); 1012 break; 1013 1014 case SO_OOBINLINE: 1015 v.val = sock_flag(sk, SOCK_URGINLINE); 1016 break; 1017 1018 case SO_NO_CHECK: 1019 v.val = sk->sk_no_check; 1020 break; 1021 1022 case SO_PRIORITY: 1023 v.val = sk->sk_priority; 1024 break; 1025 1026 case SO_LINGER: 1027 lv = sizeof(v.ling); 1028 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1029 v.ling.l_linger = sk->sk_lingertime / HZ; 1030 break; 1031 1032 case SO_BSDCOMPAT: 1033 sock_warn_obsolete_bsdism("getsockopt"); 1034 break; 1035 1036 case SO_TIMESTAMP: 1037 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1038 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1039 break; 1040 1041 case SO_TIMESTAMPNS: 1042 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 1043 break; 1044 1045 case SO_TIMESTAMPING: 1046 v.val = 0; 1047 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE)) 1048 v.val |= SOF_TIMESTAMPING_TX_HARDWARE; 1049 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE)) 1050 v.val |= SOF_TIMESTAMPING_TX_SOFTWARE; 1051 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE)) 1052 v.val |= SOF_TIMESTAMPING_RX_HARDWARE; 1053 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE)) 1054 v.val |= SOF_TIMESTAMPING_RX_SOFTWARE; 1055 if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE)) 1056 v.val |= SOF_TIMESTAMPING_SOFTWARE; 1057 if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE)) 1058 v.val |= SOF_TIMESTAMPING_SYS_HARDWARE; 1059 if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE)) 1060 v.val |= SOF_TIMESTAMPING_RAW_HARDWARE; 1061 break; 1062 1063 case SO_RCVTIMEO: 1064 lv = sizeof(struct timeval); 1065 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 1066 v.tm.tv_sec = 0; 1067 v.tm.tv_usec = 0; 1068 } else { 1069 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 1070 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 1071 } 1072 break; 1073 1074 case SO_SNDTIMEO: 1075 lv = sizeof(struct timeval); 1076 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 1077 v.tm.tv_sec = 0; 1078 v.tm.tv_usec = 0; 1079 } else { 1080 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1081 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1082 } 1083 break; 1084 1085 case SO_RCVLOWAT: 1086 v.val = sk->sk_rcvlowat; 1087 break; 1088 1089 case SO_SNDLOWAT: 1090 v.val = 1; 1091 break; 1092 1093 case SO_PASSCRED: 1094 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1095 break; 1096 1097 case SO_PEERCRED: 1098 { 1099 struct ucred peercred; 1100 if (len > sizeof(peercred)) 1101 len = sizeof(peercred); 1102 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1103 if (copy_to_user(optval, &peercred, len)) 1104 return -EFAULT; 1105 goto lenout; 1106 } 1107 1108 case SO_PEERNAME: 1109 { 1110 char address[128]; 1111 1112 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1113 return -ENOTCONN; 1114 if (lv < len) 1115 return -EINVAL; 1116 if (copy_to_user(optval, address, len)) 1117 return -EFAULT; 1118 goto lenout; 1119 } 1120 1121 /* Dubious BSD thing... Probably nobody even uses it, but 1122 * the UNIX standard wants it for whatever reason... -DaveM 1123 */ 1124 case SO_ACCEPTCONN: 1125 v.val = sk->sk_state == TCP_LISTEN; 1126 break; 1127 1128 case SO_PASSSEC: 1129 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1130 break; 1131 1132 case SO_PEERSEC: 1133 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1134 1135 case SO_MARK: 1136 v.val = sk->sk_mark; 1137 break; 1138 1139 case SO_RXQ_OVFL: 1140 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1141 break; 1142 1143 case SO_WIFI_STATUS: 1144 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1145 break; 1146 1147 case SO_PEEK_OFF: 1148 if (!sock->ops->set_peek_off) 1149 return -EOPNOTSUPP; 1150 1151 v.val = sk->sk_peek_off; 1152 break; 1153 case SO_NOFCS: 1154 v.val = sock_flag(sk, SOCK_NOFCS); 1155 break; 1156 1157 case SO_BINDTODEVICE: 1158 return sock_getbindtodevice(sk, optval, optlen, len); 1159 1160 case SO_GET_FILTER: 1161 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1162 if (len < 0) 1163 return len; 1164 1165 goto lenout; 1166 1167 case SO_LOCK_FILTER: 1168 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1169 break; 1170 1171 case SO_SELECT_ERR_QUEUE: 1172 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1173 break; 1174 1175 #ifdef CONFIG_NET_RX_BUSY_POLL 1176 case SO_BUSY_POLL: 1177 v.val = sk->sk_ll_usec; 1178 break; 1179 #endif 1180 1181 case SO_MAX_PACING_RATE: 1182 v.val = sk->sk_max_pacing_rate; 1183 break; 1184 1185 default: 1186 return -ENOPROTOOPT; 1187 } 1188 1189 if (len > lv) 1190 len = lv; 1191 if (copy_to_user(optval, &v, len)) 1192 return -EFAULT; 1193 lenout: 1194 if (put_user(len, optlen)) 1195 return -EFAULT; 1196 return 0; 1197 } 1198 1199 /* 1200 * Initialize an sk_lock. 1201 * 1202 * (We also register the sk_lock with the lock validator.) 1203 */ 1204 static inline void sock_lock_init(struct sock *sk) 1205 { 1206 sock_lock_init_class_and_name(sk, 1207 af_family_slock_key_strings[sk->sk_family], 1208 af_family_slock_keys + sk->sk_family, 1209 af_family_key_strings[sk->sk_family], 1210 af_family_keys + sk->sk_family); 1211 } 1212 1213 /* 1214 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1215 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1216 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1217 */ 1218 static void sock_copy(struct sock *nsk, const struct sock *osk) 1219 { 1220 #ifdef CONFIG_SECURITY_NETWORK 1221 void *sptr = nsk->sk_security; 1222 #endif 1223 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1224 1225 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1226 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1227 1228 #ifdef CONFIG_SECURITY_NETWORK 1229 nsk->sk_security = sptr; 1230 security_sk_clone(osk, nsk); 1231 #endif 1232 } 1233 1234 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size) 1235 { 1236 unsigned long nulls1, nulls2; 1237 1238 nulls1 = offsetof(struct sock, __sk_common.skc_node.next); 1239 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next); 1240 if (nulls1 > nulls2) 1241 swap(nulls1, nulls2); 1242 1243 if (nulls1 != 0) 1244 memset((char *)sk, 0, nulls1); 1245 memset((char *)sk + nulls1 + sizeof(void *), 0, 1246 nulls2 - nulls1 - sizeof(void *)); 1247 memset((char *)sk + nulls2 + sizeof(void *), 0, 1248 size - nulls2 - sizeof(void *)); 1249 } 1250 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls); 1251 1252 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1253 int family) 1254 { 1255 struct sock *sk; 1256 struct kmem_cache *slab; 1257 1258 slab = prot->slab; 1259 if (slab != NULL) { 1260 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1261 if (!sk) 1262 return sk; 1263 if (priority & __GFP_ZERO) { 1264 if (prot->clear_sk) 1265 prot->clear_sk(sk, prot->obj_size); 1266 else 1267 sk_prot_clear_nulls(sk, prot->obj_size); 1268 } 1269 } else 1270 sk = kmalloc(prot->obj_size, priority); 1271 1272 if (sk != NULL) { 1273 kmemcheck_annotate_bitfield(sk, flags); 1274 1275 if (security_sk_alloc(sk, family, priority)) 1276 goto out_free; 1277 1278 if (!try_module_get(prot->owner)) 1279 goto out_free_sec; 1280 sk_tx_queue_clear(sk); 1281 } 1282 1283 return sk; 1284 1285 out_free_sec: 1286 security_sk_free(sk); 1287 out_free: 1288 if (slab != NULL) 1289 kmem_cache_free(slab, sk); 1290 else 1291 kfree(sk); 1292 return NULL; 1293 } 1294 1295 static void sk_prot_free(struct proto *prot, struct sock *sk) 1296 { 1297 struct kmem_cache *slab; 1298 struct module *owner; 1299 1300 owner = prot->owner; 1301 slab = prot->slab; 1302 1303 security_sk_free(sk); 1304 if (slab != NULL) 1305 kmem_cache_free(slab, sk); 1306 else 1307 kfree(sk); 1308 module_put(owner); 1309 } 1310 1311 #if IS_ENABLED(CONFIG_NET_CLS_CGROUP) 1312 void sock_update_classid(struct sock *sk) 1313 { 1314 u32 classid; 1315 1316 classid = task_cls_classid(current); 1317 if (classid != sk->sk_classid) 1318 sk->sk_classid = classid; 1319 } 1320 EXPORT_SYMBOL(sock_update_classid); 1321 #endif 1322 1323 #if IS_ENABLED(CONFIG_NETPRIO_CGROUP) 1324 void sock_update_netprioidx(struct sock *sk) 1325 { 1326 if (in_interrupt()) 1327 return; 1328 1329 sk->sk_cgrp_prioidx = task_netprioidx(current); 1330 } 1331 EXPORT_SYMBOL_GPL(sock_update_netprioidx); 1332 #endif 1333 1334 /** 1335 * sk_alloc - All socket objects are allocated here 1336 * @net: the applicable net namespace 1337 * @family: protocol family 1338 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1339 * @prot: struct proto associated with this new sock instance 1340 */ 1341 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1342 struct proto *prot) 1343 { 1344 struct sock *sk; 1345 1346 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1347 if (sk) { 1348 sk->sk_family = family; 1349 /* 1350 * See comment in struct sock definition to understand 1351 * why we need sk_prot_creator -acme 1352 */ 1353 sk->sk_prot = sk->sk_prot_creator = prot; 1354 sock_lock_init(sk); 1355 sock_net_set(sk, get_net(net)); 1356 atomic_set(&sk->sk_wmem_alloc, 1); 1357 1358 sock_update_classid(sk); 1359 sock_update_netprioidx(sk); 1360 } 1361 1362 return sk; 1363 } 1364 EXPORT_SYMBOL(sk_alloc); 1365 1366 static void __sk_free(struct sock *sk) 1367 { 1368 struct sk_filter *filter; 1369 1370 if (sk->sk_destruct) 1371 sk->sk_destruct(sk); 1372 1373 filter = rcu_dereference_check(sk->sk_filter, 1374 atomic_read(&sk->sk_wmem_alloc) == 0); 1375 if (filter) { 1376 sk_filter_uncharge(sk, filter); 1377 RCU_INIT_POINTER(sk->sk_filter, NULL); 1378 } 1379 1380 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1381 1382 if (atomic_read(&sk->sk_omem_alloc)) 1383 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1384 __func__, atomic_read(&sk->sk_omem_alloc)); 1385 1386 if (sk->sk_peer_cred) 1387 put_cred(sk->sk_peer_cred); 1388 put_pid(sk->sk_peer_pid); 1389 put_net(sock_net(sk)); 1390 sk_prot_free(sk->sk_prot_creator, sk); 1391 } 1392 1393 void sk_free(struct sock *sk) 1394 { 1395 /* 1396 * We subtract one from sk_wmem_alloc and can know if 1397 * some packets are still in some tx queue. 1398 * If not null, sock_wfree() will call __sk_free(sk) later 1399 */ 1400 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1401 __sk_free(sk); 1402 } 1403 EXPORT_SYMBOL(sk_free); 1404 1405 /* 1406 * Last sock_put should drop reference to sk->sk_net. It has already 1407 * been dropped in sk_change_net. Taking reference to stopping namespace 1408 * is not an option. 1409 * Take reference to a socket to remove it from hash _alive_ and after that 1410 * destroy it in the context of init_net. 1411 */ 1412 void sk_release_kernel(struct sock *sk) 1413 { 1414 if (sk == NULL || sk->sk_socket == NULL) 1415 return; 1416 1417 sock_hold(sk); 1418 sock_release(sk->sk_socket); 1419 release_net(sock_net(sk)); 1420 sock_net_set(sk, get_net(&init_net)); 1421 sock_put(sk); 1422 } 1423 EXPORT_SYMBOL(sk_release_kernel); 1424 1425 static void sk_update_clone(const struct sock *sk, struct sock *newsk) 1426 { 1427 if (mem_cgroup_sockets_enabled && sk->sk_cgrp) 1428 sock_update_memcg(newsk); 1429 } 1430 1431 /** 1432 * sk_clone_lock - clone a socket, and lock its clone 1433 * @sk: the socket to clone 1434 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1435 * 1436 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1437 */ 1438 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1439 { 1440 struct sock *newsk; 1441 1442 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1443 if (newsk != NULL) { 1444 struct sk_filter *filter; 1445 1446 sock_copy(newsk, sk); 1447 1448 /* SANITY */ 1449 get_net(sock_net(newsk)); 1450 sk_node_init(&newsk->sk_node); 1451 sock_lock_init(newsk); 1452 bh_lock_sock(newsk); 1453 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1454 newsk->sk_backlog.len = 0; 1455 1456 atomic_set(&newsk->sk_rmem_alloc, 0); 1457 /* 1458 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1459 */ 1460 atomic_set(&newsk->sk_wmem_alloc, 1); 1461 atomic_set(&newsk->sk_omem_alloc, 0); 1462 skb_queue_head_init(&newsk->sk_receive_queue); 1463 skb_queue_head_init(&newsk->sk_write_queue); 1464 #ifdef CONFIG_NET_DMA 1465 skb_queue_head_init(&newsk->sk_async_wait_queue); 1466 #endif 1467 1468 spin_lock_init(&newsk->sk_dst_lock); 1469 rwlock_init(&newsk->sk_callback_lock); 1470 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1471 af_callback_keys + newsk->sk_family, 1472 af_family_clock_key_strings[newsk->sk_family]); 1473 1474 newsk->sk_dst_cache = NULL; 1475 newsk->sk_wmem_queued = 0; 1476 newsk->sk_forward_alloc = 0; 1477 newsk->sk_send_head = NULL; 1478 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1479 1480 sock_reset_flag(newsk, SOCK_DONE); 1481 skb_queue_head_init(&newsk->sk_error_queue); 1482 1483 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1484 if (filter != NULL) 1485 sk_filter_charge(newsk, filter); 1486 1487 if (unlikely(xfrm_sk_clone_policy(newsk))) { 1488 /* It is still raw copy of parent, so invalidate 1489 * destructor and make plain sk_free() */ 1490 newsk->sk_destruct = NULL; 1491 bh_unlock_sock(newsk); 1492 sk_free(newsk); 1493 newsk = NULL; 1494 goto out; 1495 } 1496 1497 newsk->sk_err = 0; 1498 newsk->sk_priority = 0; 1499 /* 1500 * Before updating sk_refcnt, we must commit prior changes to memory 1501 * (Documentation/RCU/rculist_nulls.txt for details) 1502 */ 1503 smp_wmb(); 1504 atomic_set(&newsk->sk_refcnt, 2); 1505 1506 /* 1507 * Increment the counter in the same struct proto as the master 1508 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1509 * is the same as sk->sk_prot->socks, as this field was copied 1510 * with memcpy). 1511 * 1512 * This _changes_ the previous behaviour, where 1513 * tcp_create_openreq_child always was incrementing the 1514 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1515 * to be taken into account in all callers. -acme 1516 */ 1517 sk_refcnt_debug_inc(newsk); 1518 sk_set_socket(newsk, NULL); 1519 newsk->sk_wq = NULL; 1520 1521 sk_update_clone(sk, newsk); 1522 1523 if (newsk->sk_prot->sockets_allocated) 1524 sk_sockets_allocated_inc(newsk); 1525 1526 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1527 net_enable_timestamp(); 1528 } 1529 out: 1530 return newsk; 1531 } 1532 EXPORT_SYMBOL_GPL(sk_clone_lock); 1533 1534 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1535 { 1536 __sk_dst_set(sk, dst); 1537 sk->sk_route_caps = dst->dev->features; 1538 if (sk->sk_route_caps & NETIF_F_GSO) 1539 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1540 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1541 if (sk_can_gso(sk)) { 1542 if (dst->header_len) { 1543 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1544 } else { 1545 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1546 sk->sk_gso_max_size = dst->dev->gso_max_size; 1547 sk->sk_gso_max_segs = dst->dev->gso_max_segs; 1548 } 1549 } 1550 } 1551 EXPORT_SYMBOL_GPL(sk_setup_caps); 1552 1553 /* 1554 * Simple resource managers for sockets. 1555 */ 1556 1557 1558 /* 1559 * Write buffer destructor automatically called from kfree_skb. 1560 */ 1561 void sock_wfree(struct sk_buff *skb) 1562 { 1563 struct sock *sk = skb->sk; 1564 unsigned int len = skb->truesize; 1565 1566 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1567 /* 1568 * Keep a reference on sk_wmem_alloc, this will be released 1569 * after sk_write_space() call 1570 */ 1571 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1572 sk->sk_write_space(sk); 1573 len = 1; 1574 } 1575 /* 1576 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1577 * could not do because of in-flight packets 1578 */ 1579 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1580 __sk_free(sk); 1581 } 1582 EXPORT_SYMBOL(sock_wfree); 1583 1584 void skb_orphan_partial(struct sk_buff *skb) 1585 { 1586 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc, 1587 * so we do not completely orphan skb, but transfert all 1588 * accounted bytes but one, to avoid unexpected reorders. 1589 */ 1590 if (skb->destructor == sock_wfree 1591 #ifdef CONFIG_INET 1592 || skb->destructor == tcp_wfree 1593 #endif 1594 ) { 1595 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc); 1596 skb->truesize = 1; 1597 } else { 1598 skb_orphan(skb); 1599 } 1600 } 1601 EXPORT_SYMBOL(skb_orphan_partial); 1602 1603 /* 1604 * Read buffer destructor automatically called from kfree_skb. 1605 */ 1606 void sock_rfree(struct sk_buff *skb) 1607 { 1608 struct sock *sk = skb->sk; 1609 unsigned int len = skb->truesize; 1610 1611 atomic_sub(len, &sk->sk_rmem_alloc); 1612 sk_mem_uncharge(sk, len); 1613 } 1614 EXPORT_SYMBOL(sock_rfree); 1615 1616 void sock_edemux(struct sk_buff *skb) 1617 { 1618 struct sock *sk = skb->sk; 1619 1620 #ifdef CONFIG_INET 1621 if (sk->sk_state == TCP_TIME_WAIT) 1622 inet_twsk_put(inet_twsk(sk)); 1623 else 1624 #endif 1625 sock_put(sk); 1626 } 1627 EXPORT_SYMBOL(sock_edemux); 1628 1629 kuid_t sock_i_uid(struct sock *sk) 1630 { 1631 kuid_t uid; 1632 1633 read_lock_bh(&sk->sk_callback_lock); 1634 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1635 read_unlock_bh(&sk->sk_callback_lock); 1636 return uid; 1637 } 1638 EXPORT_SYMBOL(sock_i_uid); 1639 1640 unsigned long sock_i_ino(struct sock *sk) 1641 { 1642 unsigned long ino; 1643 1644 read_lock_bh(&sk->sk_callback_lock); 1645 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1646 read_unlock_bh(&sk->sk_callback_lock); 1647 return ino; 1648 } 1649 EXPORT_SYMBOL(sock_i_ino); 1650 1651 /* 1652 * Allocate a skb from the socket's send buffer. 1653 */ 1654 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1655 gfp_t priority) 1656 { 1657 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1658 struct sk_buff *skb = alloc_skb(size, priority); 1659 if (skb) { 1660 skb_set_owner_w(skb, sk); 1661 return skb; 1662 } 1663 } 1664 return NULL; 1665 } 1666 EXPORT_SYMBOL(sock_wmalloc); 1667 1668 /* 1669 * Allocate a skb from the socket's receive buffer. 1670 */ 1671 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force, 1672 gfp_t priority) 1673 { 1674 if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) { 1675 struct sk_buff *skb = alloc_skb(size, priority); 1676 if (skb) { 1677 skb_set_owner_r(skb, sk); 1678 return skb; 1679 } 1680 } 1681 return NULL; 1682 } 1683 1684 /* 1685 * Allocate a memory block from the socket's option memory buffer. 1686 */ 1687 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1688 { 1689 if ((unsigned int)size <= sysctl_optmem_max && 1690 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1691 void *mem; 1692 /* First do the add, to avoid the race if kmalloc 1693 * might sleep. 1694 */ 1695 atomic_add(size, &sk->sk_omem_alloc); 1696 mem = kmalloc(size, priority); 1697 if (mem) 1698 return mem; 1699 atomic_sub(size, &sk->sk_omem_alloc); 1700 } 1701 return NULL; 1702 } 1703 EXPORT_SYMBOL(sock_kmalloc); 1704 1705 /* 1706 * Free an option memory block. 1707 */ 1708 void sock_kfree_s(struct sock *sk, void *mem, int size) 1709 { 1710 kfree(mem); 1711 atomic_sub(size, &sk->sk_omem_alloc); 1712 } 1713 EXPORT_SYMBOL(sock_kfree_s); 1714 1715 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1716 I think, these locks should be removed for datagram sockets. 1717 */ 1718 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1719 { 1720 DEFINE_WAIT(wait); 1721 1722 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1723 for (;;) { 1724 if (!timeo) 1725 break; 1726 if (signal_pending(current)) 1727 break; 1728 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1729 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1730 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1731 break; 1732 if (sk->sk_shutdown & SEND_SHUTDOWN) 1733 break; 1734 if (sk->sk_err) 1735 break; 1736 timeo = schedule_timeout(timeo); 1737 } 1738 finish_wait(sk_sleep(sk), &wait); 1739 return timeo; 1740 } 1741 1742 1743 /* 1744 * Generic send/receive buffer handlers 1745 */ 1746 1747 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1748 unsigned long data_len, int noblock, 1749 int *errcode, int max_page_order) 1750 { 1751 struct sk_buff *skb = NULL; 1752 unsigned long chunk; 1753 gfp_t gfp_mask; 1754 long timeo; 1755 int err; 1756 int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT; 1757 struct page *page; 1758 int i; 1759 1760 err = -EMSGSIZE; 1761 if (npages > MAX_SKB_FRAGS) 1762 goto failure; 1763 1764 timeo = sock_sndtimeo(sk, noblock); 1765 while (!skb) { 1766 err = sock_error(sk); 1767 if (err != 0) 1768 goto failure; 1769 1770 err = -EPIPE; 1771 if (sk->sk_shutdown & SEND_SHUTDOWN) 1772 goto failure; 1773 1774 if (atomic_read(&sk->sk_wmem_alloc) >= sk->sk_sndbuf) { 1775 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); 1776 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1777 err = -EAGAIN; 1778 if (!timeo) 1779 goto failure; 1780 if (signal_pending(current)) 1781 goto interrupted; 1782 timeo = sock_wait_for_wmem(sk, timeo); 1783 continue; 1784 } 1785 1786 err = -ENOBUFS; 1787 gfp_mask = sk->sk_allocation; 1788 if (gfp_mask & __GFP_WAIT) 1789 gfp_mask |= __GFP_REPEAT; 1790 1791 skb = alloc_skb(header_len, gfp_mask); 1792 if (!skb) 1793 goto failure; 1794 1795 skb->truesize += data_len; 1796 1797 for (i = 0; npages > 0; i++) { 1798 int order = max_page_order; 1799 1800 while (order) { 1801 if (npages >= 1 << order) { 1802 page = alloc_pages(sk->sk_allocation | 1803 __GFP_COMP | __GFP_NOWARN, 1804 order); 1805 if (page) 1806 goto fill_page; 1807 } 1808 order--; 1809 } 1810 page = alloc_page(sk->sk_allocation); 1811 if (!page) 1812 goto failure; 1813 fill_page: 1814 chunk = min_t(unsigned long, data_len, 1815 PAGE_SIZE << order); 1816 skb_fill_page_desc(skb, i, page, 0, chunk); 1817 data_len -= chunk; 1818 npages -= 1 << order; 1819 } 1820 } 1821 1822 skb_set_owner_w(skb, sk); 1823 return skb; 1824 1825 interrupted: 1826 err = sock_intr_errno(timeo); 1827 failure: 1828 kfree_skb(skb); 1829 *errcode = err; 1830 return NULL; 1831 } 1832 EXPORT_SYMBOL(sock_alloc_send_pskb); 1833 1834 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1835 int noblock, int *errcode) 1836 { 1837 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1838 } 1839 EXPORT_SYMBOL(sock_alloc_send_skb); 1840 1841 /* On 32bit arches, an skb frag is limited to 2^15 */ 1842 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1843 1844 /** 1845 * skb_page_frag_refill - check that a page_frag contains enough room 1846 * @sz: minimum size of the fragment we want to get 1847 * @pfrag: pointer to page_frag 1848 * @prio: priority for memory allocation 1849 * 1850 * Note: While this allocator tries to use high order pages, there is 1851 * no guarantee that allocations succeed. Therefore, @sz MUST be 1852 * less or equal than PAGE_SIZE. 1853 */ 1854 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t prio) 1855 { 1856 int order; 1857 1858 if (pfrag->page) { 1859 if (atomic_read(&pfrag->page->_count) == 1) { 1860 pfrag->offset = 0; 1861 return true; 1862 } 1863 if (pfrag->offset + sz <= pfrag->size) 1864 return true; 1865 put_page(pfrag->page); 1866 } 1867 1868 /* We restrict high order allocations to users that can afford to wait */ 1869 order = (prio & __GFP_WAIT) ? SKB_FRAG_PAGE_ORDER : 0; 1870 1871 do { 1872 gfp_t gfp = prio; 1873 1874 if (order) 1875 gfp |= __GFP_COMP | __GFP_NOWARN; 1876 pfrag->page = alloc_pages(gfp, order); 1877 if (likely(pfrag->page)) { 1878 pfrag->offset = 0; 1879 pfrag->size = PAGE_SIZE << order; 1880 return true; 1881 } 1882 } while (--order >= 0); 1883 1884 return false; 1885 } 1886 EXPORT_SYMBOL(skb_page_frag_refill); 1887 1888 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 1889 { 1890 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 1891 return true; 1892 1893 sk_enter_memory_pressure(sk); 1894 sk_stream_moderate_sndbuf(sk); 1895 return false; 1896 } 1897 EXPORT_SYMBOL(sk_page_frag_refill); 1898 1899 static void __lock_sock(struct sock *sk) 1900 __releases(&sk->sk_lock.slock) 1901 __acquires(&sk->sk_lock.slock) 1902 { 1903 DEFINE_WAIT(wait); 1904 1905 for (;;) { 1906 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 1907 TASK_UNINTERRUPTIBLE); 1908 spin_unlock_bh(&sk->sk_lock.slock); 1909 schedule(); 1910 spin_lock_bh(&sk->sk_lock.slock); 1911 if (!sock_owned_by_user(sk)) 1912 break; 1913 } 1914 finish_wait(&sk->sk_lock.wq, &wait); 1915 } 1916 1917 static void __release_sock(struct sock *sk) 1918 __releases(&sk->sk_lock.slock) 1919 __acquires(&sk->sk_lock.slock) 1920 { 1921 struct sk_buff *skb = sk->sk_backlog.head; 1922 1923 do { 1924 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 1925 bh_unlock_sock(sk); 1926 1927 do { 1928 struct sk_buff *next = skb->next; 1929 1930 prefetch(next); 1931 WARN_ON_ONCE(skb_dst_is_noref(skb)); 1932 skb->next = NULL; 1933 sk_backlog_rcv(sk, skb); 1934 1935 /* 1936 * We are in process context here with softirqs 1937 * disabled, use cond_resched_softirq() to preempt. 1938 * This is safe to do because we've taken the backlog 1939 * queue private: 1940 */ 1941 cond_resched_softirq(); 1942 1943 skb = next; 1944 } while (skb != NULL); 1945 1946 bh_lock_sock(sk); 1947 } while ((skb = sk->sk_backlog.head) != NULL); 1948 1949 /* 1950 * Doing the zeroing here guarantee we can not loop forever 1951 * while a wild producer attempts to flood us. 1952 */ 1953 sk->sk_backlog.len = 0; 1954 } 1955 1956 /** 1957 * sk_wait_data - wait for data to arrive at sk_receive_queue 1958 * @sk: sock to wait on 1959 * @timeo: for how long 1960 * 1961 * Now socket state including sk->sk_err is changed only under lock, 1962 * hence we may omit checks after joining wait queue. 1963 * We check receive queue before schedule() only as optimization; 1964 * it is very likely that release_sock() added new data. 1965 */ 1966 int sk_wait_data(struct sock *sk, long *timeo) 1967 { 1968 int rc; 1969 DEFINE_WAIT(wait); 1970 1971 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1972 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1973 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); 1974 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); 1975 finish_wait(sk_sleep(sk), &wait); 1976 return rc; 1977 } 1978 EXPORT_SYMBOL(sk_wait_data); 1979 1980 /** 1981 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 1982 * @sk: socket 1983 * @size: memory size to allocate 1984 * @kind: allocation type 1985 * 1986 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 1987 * rmem allocation. This function assumes that protocols which have 1988 * memory_pressure use sk_wmem_queued as write buffer accounting. 1989 */ 1990 int __sk_mem_schedule(struct sock *sk, int size, int kind) 1991 { 1992 struct proto *prot = sk->sk_prot; 1993 int amt = sk_mem_pages(size); 1994 long allocated; 1995 int parent_status = UNDER_LIMIT; 1996 1997 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM; 1998 1999 allocated = sk_memory_allocated_add(sk, amt, &parent_status); 2000 2001 /* Under limit. */ 2002 if (parent_status == UNDER_LIMIT && 2003 allocated <= sk_prot_mem_limits(sk, 0)) { 2004 sk_leave_memory_pressure(sk); 2005 return 1; 2006 } 2007 2008 /* Under pressure. (we or our parents) */ 2009 if ((parent_status > SOFT_LIMIT) || 2010 allocated > sk_prot_mem_limits(sk, 1)) 2011 sk_enter_memory_pressure(sk); 2012 2013 /* Over hard limit (we or our parents) */ 2014 if ((parent_status == OVER_LIMIT) || 2015 (allocated > sk_prot_mem_limits(sk, 2))) 2016 goto suppress_allocation; 2017 2018 /* guarantee minimum buffer size under pressure */ 2019 if (kind == SK_MEM_RECV) { 2020 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 2021 return 1; 2022 2023 } else { /* SK_MEM_SEND */ 2024 if (sk->sk_type == SOCK_STREAM) { 2025 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 2026 return 1; 2027 } else if (atomic_read(&sk->sk_wmem_alloc) < 2028 prot->sysctl_wmem[0]) 2029 return 1; 2030 } 2031 2032 if (sk_has_memory_pressure(sk)) { 2033 int alloc; 2034 2035 if (!sk_under_memory_pressure(sk)) 2036 return 1; 2037 alloc = sk_sockets_allocated_read_positive(sk); 2038 if (sk_prot_mem_limits(sk, 2) > alloc * 2039 sk_mem_pages(sk->sk_wmem_queued + 2040 atomic_read(&sk->sk_rmem_alloc) + 2041 sk->sk_forward_alloc)) 2042 return 1; 2043 } 2044 2045 suppress_allocation: 2046 2047 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2048 sk_stream_moderate_sndbuf(sk); 2049 2050 /* Fail only if socket is _under_ its sndbuf. 2051 * In this case we cannot block, so that we have to fail. 2052 */ 2053 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2054 return 1; 2055 } 2056 2057 trace_sock_exceed_buf_limit(sk, prot, allocated); 2058 2059 /* Alas. Undo changes. */ 2060 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM; 2061 2062 sk_memory_allocated_sub(sk, amt); 2063 2064 return 0; 2065 } 2066 EXPORT_SYMBOL(__sk_mem_schedule); 2067 2068 /** 2069 * __sk_reclaim - reclaim memory_allocated 2070 * @sk: socket 2071 */ 2072 void __sk_mem_reclaim(struct sock *sk) 2073 { 2074 sk_memory_allocated_sub(sk, 2075 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT); 2076 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1; 2077 2078 if (sk_under_memory_pressure(sk) && 2079 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2080 sk_leave_memory_pressure(sk); 2081 } 2082 EXPORT_SYMBOL(__sk_mem_reclaim); 2083 2084 2085 /* 2086 * Set of default routines for initialising struct proto_ops when 2087 * the protocol does not support a particular function. In certain 2088 * cases where it makes no sense for a protocol to have a "do nothing" 2089 * function, some default processing is provided. 2090 */ 2091 2092 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2093 { 2094 return -EOPNOTSUPP; 2095 } 2096 EXPORT_SYMBOL(sock_no_bind); 2097 2098 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2099 int len, int flags) 2100 { 2101 return -EOPNOTSUPP; 2102 } 2103 EXPORT_SYMBOL(sock_no_connect); 2104 2105 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2106 { 2107 return -EOPNOTSUPP; 2108 } 2109 EXPORT_SYMBOL(sock_no_socketpair); 2110 2111 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 2112 { 2113 return -EOPNOTSUPP; 2114 } 2115 EXPORT_SYMBOL(sock_no_accept); 2116 2117 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2118 int *len, int peer) 2119 { 2120 return -EOPNOTSUPP; 2121 } 2122 EXPORT_SYMBOL(sock_no_getname); 2123 2124 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 2125 { 2126 return 0; 2127 } 2128 EXPORT_SYMBOL(sock_no_poll); 2129 2130 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2131 { 2132 return -EOPNOTSUPP; 2133 } 2134 EXPORT_SYMBOL(sock_no_ioctl); 2135 2136 int sock_no_listen(struct socket *sock, int backlog) 2137 { 2138 return -EOPNOTSUPP; 2139 } 2140 EXPORT_SYMBOL(sock_no_listen); 2141 2142 int sock_no_shutdown(struct socket *sock, int how) 2143 { 2144 return -EOPNOTSUPP; 2145 } 2146 EXPORT_SYMBOL(sock_no_shutdown); 2147 2148 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2149 char __user *optval, unsigned int optlen) 2150 { 2151 return -EOPNOTSUPP; 2152 } 2153 EXPORT_SYMBOL(sock_no_setsockopt); 2154 2155 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2156 char __user *optval, int __user *optlen) 2157 { 2158 return -EOPNOTSUPP; 2159 } 2160 EXPORT_SYMBOL(sock_no_getsockopt); 2161 2162 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2163 size_t len) 2164 { 2165 return -EOPNOTSUPP; 2166 } 2167 EXPORT_SYMBOL(sock_no_sendmsg); 2168 2169 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, 2170 size_t len, int flags) 2171 { 2172 return -EOPNOTSUPP; 2173 } 2174 EXPORT_SYMBOL(sock_no_recvmsg); 2175 2176 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2177 { 2178 /* Mirror missing mmap method error code */ 2179 return -ENODEV; 2180 } 2181 EXPORT_SYMBOL(sock_no_mmap); 2182 2183 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2184 { 2185 ssize_t res; 2186 struct msghdr msg = {.msg_flags = flags}; 2187 struct kvec iov; 2188 char *kaddr = kmap(page); 2189 iov.iov_base = kaddr + offset; 2190 iov.iov_len = size; 2191 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2192 kunmap(page); 2193 return res; 2194 } 2195 EXPORT_SYMBOL(sock_no_sendpage); 2196 2197 /* 2198 * Default Socket Callbacks 2199 */ 2200 2201 static void sock_def_wakeup(struct sock *sk) 2202 { 2203 struct socket_wq *wq; 2204 2205 rcu_read_lock(); 2206 wq = rcu_dereference(sk->sk_wq); 2207 if (wq_has_sleeper(wq)) 2208 wake_up_interruptible_all(&wq->wait); 2209 rcu_read_unlock(); 2210 } 2211 2212 static void sock_def_error_report(struct sock *sk) 2213 { 2214 struct socket_wq *wq; 2215 2216 rcu_read_lock(); 2217 wq = rcu_dereference(sk->sk_wq); 2218 if (wq_has_sleeper(wq)) 2219 wake_up_interruptible_poll(&wq->wait, POLLERR); 2220 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2221 rcu_read_unlock(); 2222 } 2223 2224 static void sock_def_readable(struct sock *sk, int len) 2225 { 2226 struct socket_wq *wq; 2227 2228 rcu_read_lock(); 2229 wq = rcu_dereference(sk->sk_wq); 2230 if (wq_has_sleeper(wq)) 2231 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI | 2232 POLLRDNORM | POLLRDBAND); 2233 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2234 rcu_read_unlock(); 2235 } 2236 2237 static void sock_def_write_space(struct sock *sk) 2238 { 2239 struct socket_wq *wq; 2240 2241 rcu_read_lock(); 2242 2243 /* Do not wake up a writer until he can make "significant" 2244 * progress. --DaveM 2245 */ 2246 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2247 wq = rcu_dereference(sk->sk_wq); 2248 if (wq_has_sleeper(wq)) 2249 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 2250 POLLWRNORM | POLLWRBAND); 2251 2252 /* Should agree with poll, otherwise some programs break */ 2253 if (sock_writeable(sk)) 2254 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2255 } 2256 2257 rcu_read_unlock(); 2258 } 2259 2260 static void sock_def_destruct(struct sock *sk) 2261 { 2262 kfree(sk->sk_protinfo); 2263 } 2264 2265 void sk_send_sigurg(struct sock *sk) 2266 { 2267 if (sk->sk_socket && sk->sk_socket->file) 2268 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2269 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2270 } 2271 EXPORT_SYMBOL(sk_send_sigurg); 2272 2273 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2274 unsigned long expires) 2275 { 2276 if (!mod_timer(timer, expires)) 2277 sock_hold(sk); 2278 } 2279 EXPORT_SYMBOL(sk_reset_timer); 2280 2281 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2282 { 2283 if (del_timer(timer)) 2284 __sock_put(sk); 2285 } 2286 EXPORT_SYMBOL(sk_stop_timer); 2287 2288 void sock_init_data(struct socket *sock, struct sock *sk) 2289 { 2290 skb_queue_head_init(&sk->sk_receive_queue); 2291 skb_queue_head_init(&sk->sk_write_queue); 2292 skb_queue_head_init(&sk->sk_error_queue); 2293 #ifdef CONFIG_NET_DMA 2294 skb_queue_head_init(&sk->sk_async_wait_queue); 2295 #endif 2296 2297 sk->sk_send_head = NULL; 2298 2299 init_timer(&sk->sk_timer); 2300 2301 sk->sk_allocation = GFP_KERNEL; 2302 sk->sk_rcvbuf = sysctl_rmem_default; 2303 sk->sk_sndbuf = sysctl_wmem_default; 2304 sk->sk_state = TCP_CLOSE; 2305 sk_set_socket(sk, sock); 2306 2307 sock_set_flag(sk, SOCK_ZAPPED); 2308 2309 if (sock) { 2310 sk->sk_type = sock->type; 2311 sk->sk_wq = sock->wq; 2312 sock->sk = sk; 2313 } else 2314 sk->sk_wq = NULL; 2315 2316 spin_lock_init(&sk->sk_dst_lock); 2317 rwlock_init(&sk->sk_callback_lock); 2318 lockdep_set_class_and_name(&sk->sk_callback_lock, 2319 af_callback_keys + sk->sk_family, 2320 af_family_clock_key_strings[sk->sk_family]); 2321 2322 sk->sk_state_change = sock_def_wakeup; 2323 sk->sk_data_ready = sock_def_readable; 2324 sk->sk_write_space = sock_def_write_space; 2325 sk->sk_error_report = sock_def_error_report; 2326 sk->sk_destruct = sock_def_destruct; 2327 2328 sk->sk_frag.page = NULL; 2329 sk->sk_frag.offset = 0; 2330 sk->sk_peek_off = -1; 2331 2332 sk->sk_peer_pid = NULL; 2333 sk->sk_peer_cred = NULL; 2334 sk->sk_write_pending = 0; 2335 sk->sk_rcvlowat = 1; 2336 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2337 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2338 2339 sk->sk_stamp = ktime_set(-1L, 0); 2340 2341 #ifdef CONFIG_NET_RX_BUSY_POLL 2342 sk->sk_napi_id = 0; 2343 sk->sk_ll_usec = sysctl_net_busy_read; 2344 #endif 2345 2346 sk->sk_max_pacing_rate = ~0U; 2347 sk->sk_pacing_rate = ~0U; 2348 /* 2349 * Before updating sk_refcnt, we must commit prior changes to memory 2350 * (Documentation/RCU/rculist_nulls.txt for details) 2351 */ 2352 smp_wmb(); 2353 atomic_set(&sk->sk_refcnt, 1); 2354 atomic_set(&sk->sk_drops, 0); 2355 } 2356 EXPORT_SYMBOL(sock_init_data); 2357 2358 void lock_sock_nested(struct sock *sk, int subclass) 2359 { 2360 might_sleep(); 2361 spin_lock_bh(&sk->sk_lock.slock); 2362 if (sk->sk_lock.owned) 2363 __lock_sock(sk); 2364 sk->sk_lock.owned = 1; 2365 spin_unlock(&sk->sk_lock.slock); 2366 /* 2367 * The sk_lock has mutex_lock() semantics here: 2368 */ 2369 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2370 local_bh_enable(); 2371 } 2372 EXPORT_SYMBOL(lock_sock_nested); 2373 2374 void release_sock(struct sock *sk) 2375 { 2376 /* 2377 * The sk_lock has mutex_unlock() semantics: 2378 */ 2379 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 2380 2381 spin_lock_bh(&sk->sk_lock.slock); 2382 if (sk->sk_backlog.tail) 2383 __release_sock(sk); 2384 2385 if (sk->sk_prot->release_cb) 2386 sk->sk_prot->release_cb(sk); 2387 2388 sk->sk_lock.owned = 0; 2389 if (waitqueue_active(&sk->sk_lock.wq)) 2390 wake_up(&sk->sk_lock.wq); 2391 spin_unlock_bh(&sk->sk_lock.slock); 2392 } 2393 EXPORT_SYMBOL(release_sock); 2394 2395 /** 2396 * lock_sock_fast - fast version of lock_sock 2397 * @sk: socket 2398 * 2399 * This version should be used for very small section, where process wont block 2400 * return false if fast path is taken 2401 * sk_lock.slock locked, owned = 0, BH disabled 2402 * return true if slow path is taken 2403 * sk_lock.slock unlocked, owned = 1, BH enabled 2404 */ 2405 bool lock_sock_fast(struct sock *sk) 2406 { 2407 might_sleep(); 2408 spin_lock_bh(&sk->sk_lock.slock); 2409 2410 if (!sk->sk_lock.owned) 2411 /* 2412 * Note : We must disable BH 2413 */ 2414 return false; 2415 2416 __lock_sock(sk); 2417 sk->sk_lock.owned = 1; 2418 spin_unlock(&sk->sk_lock.slock); 2419 /* 2420 * The sk_lock has mutex_lock() semantics here: 2421 */ 2422 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2423 local_bh_enable(); 2424 return true; 2425 } 2426 EXPORT_SYMBOL(lock_sock_fast); 2427 2428 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2429 { 2430 struct timeval tv; 2431 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2432 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2433 tv = ktime_to_timeval(sk->sk_stamp); 2434 if (tv.tv_sec == -1) 2435 return -ENOENT; 2436 if (tv.tv_sec == 0) { 2437 sk->sk_stamp = ktime_get_real(); 2438 tv = ktime_to_timeval(sk->sk_stamp); 2439 } 2440 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2441 } 2442 EXPORT_SYMBOL(sock_get_timestamp); 2443 2444 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2445 { 2446 struct timespec ts; 2447 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2448 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2449 ts = ktime_to_timespec(sk->sk_stamp); 2450 if (ts.tv_sec == -1) 2451 return -ENOENT; 2452 if (ts.tv_sec == 0) { 2453 sk->sk_stamp = ktime_get_real(); 2454 ts = ktime_to_timespec(sk->sk_stamp); 2455 } 2456 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2457 } 2458 EXPORT_SYMBOL(sock_get_timestampns); 2459 2460 void sock_enable_timestamp(struct sock *sk, int flag) 2461 { 2462 if (!sock_flag(sk, flag)) { 2463 unsigned long previous_flags = sk->sk_flags; 2464 2465 sock_set_flag(sk, flag); 2466 /* 2467 * we just set one of the two flags which require net 2468 * time stamping, but time stamping might have been on 2469 * already because of the other one 2470 */ 2471 if (!(previous_flags & SK_FLAGS_TIMESTAMP)) 2472 net_enable_timestamp(); 2473 } 2474 } 2475 2476 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 2477 int level, int type) 2478 { 2479 struct sock_exterr_skb *serr; 2480 struct sk_buff *skb, *skb2; 2481 int copied, err; 2482 2483 err = -EAGAIN; 2484 skb = skb_dequeue(&sk->sk_error_queue); 2485 if (skb == NULL) 2486 goto out; 2487 2488 copied = skb->len; 2489 if (copied > len) { 2490 msg->msg_flags |= MSG_TRUNC; 2491 copied = len; 2492 } 2493 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 2494 if (err) 2495 goto out_free_skb; 2496 2497 sock_recv_timestamp(msg, sk, skb); 2498 2499 serr = SKB_EXT_ERR(skb); 2500 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 2501 2502 msg->msg_flags |= MSG_ERRQUEUE; 2503 err = copied; 2504 2505 /* Reset and regenerate socket error */ 2506 spin_lock_bh(&sk->sk_error_queue.lock); 2507 sk->sk_err = 0; 2508 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) { 2509 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno; 2510 spin_unlock_bh(&sk->sk_error_queue.lock); 2511 sk->sk_error_report(sk); 2512 } else 2513 spin_unlock_bh(&sk->sk_error_queue.lock); 2514 2515 out_free_skb: 2516 kfree_skb(skb); 2517 out: 2518 return err; 2519 } 2520 EXPORT_SYMBOL(sock_recv_errqueue); 2521 2522 /* 2523 * Get a socket option on an socket. 2524 * 2525 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2526 * asynchronous errors should be reported by getsockopt. We assume 2527 * this means if you specify SO_ERROR (otherwise whats the point of it). 2528 */ 2529 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2530 char __user *optval, int __user *optlen) 2531 { 2532 struct sock *sk = sock->sk; 2533 2534 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2535 } 2536 EXPORT_SYMBOL(sock_common_getsockopt); 2537 2538 #ifdef CONFIG_COMPAT 2539 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2540 char __user *optval, int __user *optlen) 2541 { 2542 struct sock *sk = sock->sk; 2543 2544 if (sk->sk_prot->compat_getsockopt != NULL) 2545 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2546 optval, optlen); 2547 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2548 } 2549 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2550 #endif 2551 2552 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, 2553 struct msghdr *msg, size_t size, int flags) 2554 { 2555 struct sock *sk = sock->sk; 2556 int addr_len = 0; 2557 int err; 2558 2559 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT, 2560 flags & ~MSG_DONTWAIT, &addr_len); 2561 if (err >= 0) 2562 msg->msg_namelen = addr_len; 2563 return err; 2564 } 2565 EXPORT_SYMBOL(sock_common_recvmsg); 2566 2567 /* 2568 * Set socket options on an inet socket. 2569 */ 2570 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2571 char __user *optval, unsigned int optlen) 2572 { 2573 struct sock *sk = sock->sk; 2574 2575 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2576 } 2577 EXPORT_SYMBOL(sock_common_setsockopt); 2578 2579 #ifdef CONFIG_COMPAT 2580 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2581 char __user *optval, unsigned int optlen) 2582 { 2583 struct sock *sk = sock->sk; 2584 2585 if (sk->sk_prot->compat_setsockopt != NULL) 2586 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2587 optval, optlen); 2588 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2589 } 2590 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2591 #endif 2592 2593 void sk_common_release(struct sock *sk) 2594 { 2595 if (sk->sk_prot->destroy) 2596 sk->sk_prot->destroy(sk); 2597 2598 /* 2599 * Observation: when sock_common_release is called, processes have 2600 * no access to socket. But net still has. 2601 * Step one, detach it from networking: 2602 * 2603 * A. Remove from hash tables. 2604 */ 2605 2606 sk->sk_prot->unhash(sk); 2607 2608 /* 2609 * In this point socket cannot receive new packets, but it is possible 2610 * that some packets are in flight because some CPU runs receiver and 2611 * did hash table lookup before we unhashed socket. They will achieve 2612 * receive queue and will be purged by socket destructor. 2613 * 2614 * Also we still have packets pending on receive queue and probably, 2615 * our own packets waiting in device queues. sock_destroy will drain 2616 * receive queue, but transmitted packets will delay socket destruction 2617 * until the last reference will be released. 2618 */ 2619 2620 sock_orphan(sk); 2621 2622 xfrm_sk_free_policy(sk); 2623 2624 sk_refcnt_debug_release(sk); 2625 2626 if (sk->sk_frag.page) { 2627 put_page(sk->sk_frag.page); 2628 sk->sk_frag.page = NULL; 2629 } 2630 2631 sock_put(sk); 2632 } 2633 EXPORT_SYMBOL(sk_common_release); 2634 2635 #ifdef CONFIG_PROC_FS 2636 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2637 struct prot_inuse { 2638 int val[PROTO_INUSE_NR]; 2639 }; 2640 2641 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2642 2643 #ifdef CONFIG_NET_NS 2644 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2645 { 2646 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2647 } 2648 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2649 2650 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2651 { 2652 int cpu, idx = prot->inuse_idx; 2653 int res = 0; 2654 2655 for_each_possible_cpu(cpu) 2656 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2657 2658 return res >= 0 ? res : 0; 2659 } 2660 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2661 2662 static int __net_init sock_inuse_init_net(struct net *net) 2663 { 2664 net->core.inuse = alloc_percpu(struct prot_inuse); 2665 return net->core.inuse ? 0 : -ENOMEM; 2666 } 2667 2668 static void __net_exit sock_inuse_exit_net(struct net *net) 2669 { 2670 free_percpu(net->core.inuse); 2671 } 2672 2673 static struct pernet_operations net_inuse_ops = { 2674 .init = sock_inuse_init_net, 2675 .exit = sock_inuse_exit_net, 2676 }; 2677 2678 static __init int net_inuse_init(void) 2679 { 2680 if (register_pernet_subsys(&net_inuse_ops)) 2681 panic("Cannot initialize net inuse counters"); 2682 2683 return 0; 2684 } 2685 2686 core_initcall(net_inuse_init); 2687 #else 2688 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2689 2690 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2691 { 2692 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2693 } 2694 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2695 2696 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2697 { 2698 int cpu, idx = prot->inuse_idx; 2699 int res = 0; 2700 2701 for_each_possible_cpu(cpu) 2702 res += per_cpu(prot_inuse, cpu).val[idx]; 2703 2704 return res >= 0 ? res : 0; 2705 } 2706 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2707 #endif 2708 2709 static void assign_proto_idx(struct proto *prot) 2710 { 2711 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2712 2713 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2714 pr_err("PROTO_INUSE_NR exhausted\n"); 2715 return; 2716 } 2717 2718 set_bit(prot->inuse_idx, proto_inuse_idx); 2719 } 2720 2721 static void release_proto_idx(struct proto *prot) 2722 { 2723 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2724 clear_bit(prot->inuse_idx, proto_inuse_idx); 2725 } 2726 #else 2727 static inline void assign_proto_idx(struct proto *prot) 2728 { 2729 } 2730 2731 static inline void release_proto_idx(struct proto *prot) 2732 { 2733 } 2734 #endif 2735 2736 int proto_register(struct proto *prot, int alloc_slab) 2737 { 2738 if (alloc_slab) { 2739 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2740 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2741 NULL); 2742 2743 if (prot->slab == NULL) { 2744 pr_crit("%s: Can't create sock SLAB cache!\n", 2745 prot->name); 2746 goto out; 2747 } 2748 2749 if (prot->rsk_prot != NULL) { 2750 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name); 2751 if (prot->rsk_prot->slab_name == NULL) 2752 goto out_free_sock_slab; 2753 2754 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name, 2755 prot->rsk_prot->obj_size, 0, 2756 SLAB_HWCACHE_ALIGN, NULL); 2757 2758 if (prot->rsk_prot->slab == NULL) { 2759 pr_crit("%s: Can't create request sock SLAB cache!\n", 2760 prot->name); 2761 goto out_free_request_sock_slab_name; 2762 } 2763 } 2764 2765 if (prot->twsk_prot != NULL) { 2766 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2767 2768 if (prot->twsk_prot->twsk_slab_name == NULL) 2769 goto out_free_request_sock_slab; 2770 2771 prot->twsk_prot->twsk_slab = 2772 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2773 prot->twsk_prot->twsk_obj_size, 2774 0, 2775 SLAB_HWCACHE_ALIGN | 2776 prot->slab_flags, 2777 NULL); 2778 if (prot->twsk_prot->twsk_slab == NULL) 2779 goto out_free_timewait_sock_slab_name; 2780 } 2781 } 2782 2783 mutex_lock(&proto_list_mutex); 2784 list_add(&prot->node, &proto_list); 2785 assign_proto_idx(prot); 2786 mutex_unlock(&proto_list_mutex); 2787 return 0; 2788 2789 out_free_timewait_sock_slab_name: 2790 kfree(prot->twsk_prot->twsk_slab_name); 2791 out_free_request_sock_slab: 2792 if (prot->rsk_prot && prot->rsk_prot->slab) { 2793 kmem_cache_destroy(prot->rsk_prot->slab); 2794 prot->rsk_prot->slab = NULL; 2795 } 2796 out_free_request_sock_slab_name: 2797 if (prot->rsk_prot) 2798 kfree(prot->rsk_prot->slab_name); 2799 out_free_sock_slab: 2800 kmem_cache_destroy(prot->slab); 2801 prot->slab = NULL; 2802 out: 2803 return -ENOBUFS; 2804 } 2805 EXPORT_SYMBOL(proto_register); 2806 2807 void proto_unregister(struct proto *prot) 2808 { 2809 mutex_lock(&proto_list_mutex); 2810 release_proto_idx(prot); 2811 list_del(&prot->node); 2812 mutex_unlock(&proto_list_mutex); 2813 2814 if (prot->slab != NULL) { 2815 kmem_cache_destroy(prot->slab); 2816 prot->slab = NULL; 2817 } 2818 2819 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) { 2820 kmem_cache_destroy(prot->rsk_prot->slab); 2821 kfree(prot->rsk_prot->slab_name); 2822 prot->rsk_prot->slab = NULL; 2823 } 2824 2825 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2826 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2827 kfree(prot->twsk_prot->twsk_slab_name); 2828 prot->twsk_prot->twsk_slab = NULL; 2829 } 2830 } 2831 EXPORT_SYMBOL(proto_unregister); 2832 2833 #ifdef CONFIG_PROC_FS 2834 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2835 __acquires(proto_list_mutex) 2836 { 2837 mutex_lock(&proto_list_mutex); 2838 return seq_list_start_head(&proto_list, *pos); 2839 } 2840 2841 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2842 { 2843 return seq_list_next(v, &proto_list, pos); 2844 } 2845 2846 static void proto_seq_stop(struct seq_file *seq, void *v) 2847 __releases(proto_list_mutex) 2848 { 2849 mutex_unlock(&proto_list_mutex); 2850 } 2851 2852 static char proto_method_implemented(const void *method) 2853 { 2854 return method == NULL ? 'n' : 'y'; 2855 } 2856 static long sock_prot_memory_allocated(struct proto *proto) 2857 { 2858 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 2859 } 2860 2861 static char *sock_prot_memory_pressure(struct proto *proto) 2862 { 2863 return proto->memory_pressure != NULL ? 2864 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 2865 } 2866 2867 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 2868 { 2869 2870 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 2871 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 2872 proto->name, 2873 proto->obj_size, 2874 sock_prot_inuse_get(seq_file_net(seq), proto), 2875 sock_prot_memory_allocated(proto), 2876 sock_prot_memory_pressure(proto), 2877 proto->max_header, 2878 proto->slab == NULL ? "no" : "yes", 2879 module_name(proto->owner), 2880 proto_method_implemented(proto->close), 2881 proto_method_implemented(proto->connect), 2882 proto_method_implemented(proto->disconnect), 2883 proto_method_implemented(proto->accept), 2884 proto_method_implemented(proto->ioctl), 2885 proto_method_implemented(proto->init), 2886 proto_method_implemented(proto->destroy), 2887 proto_method_implemented(proto->shutdown), 2888 proto_method_implemented(proto->setsockopt), 2889 proto_method_implemented(proto->getsockopt), 2890 proto_method_implemented(proto->sendmsg), 2891 proto_method_implemented(proto->recvmsg), 2892 proto_method_implemented(proto->sendpage), 2893 proto_method_implemented(proto->bind), 2894 proto_method_implemented(proto->backlog_rcv), 2895 proto_method_implemented(proto->hash), 2896 proto_method_implemented(proto->unhash), 2897 proto_method_implemented(proto->get_port), 2898 proto_method_implemented(proto->enter_memory_pressure)); 2899 } 2900 2901 static int proto_seq_show(struct seq_file *seq, void *v) 2902 { 2903 if (v == &proto_list) 2904 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 2905 "protocol", 2906 "size", 2907 "sockets", 2908 "memory", 2909 "press", 2910 "maxhdr", 2911 "slab", 2912 "module", 2913 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 2914 else 2915 proto_seq_printf(seq, list_entry(v, struct proto, node)); 2916 return 0; 2917 } 2918 2919 static const struct seq_operations proto_seq_ops = { 2920 .start = proto_seq_start, 2921 .next = proto_seq_next, 2922 .stop = proto_seq_stop, 2923 .show = proto_seq_show, 2924 }; 2925 2926 static int proto_seq_open(struct inode *inode, struct file *file) 2927 { 2928 return seq_open_net(inode, file, &proto_seq_ops, 2929 sizeof(struct seq_net_private)); 2930 } 2931 2932 static const struct file_operations proto_seq_fops = { 2933 .owner = THIS_MODULE, 2934 .open = proto_seq_open, 2935 .read = seq_read, 2936 .llseek = seq_lseek, 2937 .release = seq_release_net, 2938 }; 2939 2940 static __net_init int proto_init_net(struct net *net) 2941 { 2942 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops)) 2943 return -ENOMEM; 2944 2945 return 0; 2946 } 2947 2948 static __net_exit void proto_exit_net(struct net *net) 2949 { 2950 remove_proc_entry("protocols", net->proc_net); 2951 } 2952 2953 2954 static __net_initdata struct pernet_operations proto_net_ops = { 2955 .init = proto_init_net, 2956 .exit = proto_exit_net, 2957 }; 2958 2959 static int __init proto_init(void) 2960 { 2961 return register_pernet_subsys(&proto_net_ops); 2962 } 2963 2964 subsys_initcall(proto_init); 2965 2966 #endif /* PROC_FS */ 2967