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 <linux/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 #include <linux/sock_diag.h> 135 136 #include <linux/filter.h> 137 #include <net/sock_reuseport.h> 138 139 #include <trace/events/sock.h> 140 141 #ifdef CONFIG_INET 142 #include <net/tcp.h> 143 #endif 144 145 #include <net/busy_poll.h> 146 147 static DEFINE_MUTEX(proto_list_mutex); 148 static LIST_HEAD(proto_list); 149 150 /** 151 * sk_ns_capable - General socket capability test 152 * @sk: Socket to use a capability on or through 153 * @user_ns: The user namespace of the capability to use 154 * @cap: The capability to use 155 * 156 * Test to see if the opener of the socket had when the socket was 157 * created and the current process has the capability @cap in the user 158 * namespace @user_ns. 159 */ 160 bool sk_ns_capable(const struct sock *sk, 161 struct user_namespace *user_ns, int cap) 162 { 163 return file_ns_capable(sk->sk_socket->file, user_ns, cap) && 164 ns_capable(user_ns, cap); 165 } 166 EXPORT_SYMBOL(sk_ns_capable); 167 168 /** 169 * sk_capable - Socket global capability test 170 * @sk: Socket to use a capability on or through 171 * @cap: The global capability to use 172 * 173 * Test to see if the opener of the socket had when the socket was 174 * created and the current process has the capability @cap in all user 175 * namespaces. 176 */ 177 bool sk_capable(const struct sock *sk, int cap) 178 { 179 return sk_ns_capable(sk, &init_user_ns, cap); 180 } 181 EXPORT_SYMBOL(sk_capable); 182 183 /** 184 * sk_net_capable - Network namespace socket capability test 185 * @sk: Socket to use a capability on or through 186 * @cap: The capability to use 187 * 188 * Test to see if the opener of the socket had when the socket was created 189 * and the current process has the capability @cap over the network namespace 190 * the socket is a member of. 191 */ 192 bool sk_net_capable(const struct sock *sk, int cap) 193 { 194 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap); 195 } 196 EXPORT_SYMBOL(sk_net_capable); 197 198 /* 199 * Each address family might have different locking rules, so we have 200 * one slock key per address family: 201 */ 202 static struct lock_class_key af_family_keys[AF_MAX]; 203 static struct lock_class_key af_family_slock_keys[AF_MAX]; 204 205 /* 206 * Make lock validator output more readable. (we pre-construct these 207 * strings build-time, so that runtime initialization of socket 208 * locks is fast): 209 */ 210 static const char *const af_family_key_strings[AF_MAX+1] = { 211 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" , 212 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK", 213 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" , 214 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" , 215 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" , 216 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" , 217 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" , 218 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" , 219 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" , 220 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" , 221 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" , 222 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" , 223 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" , 224 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_KCM" , 225 "sk_lock-AF_QIPCRTR", "sk_lock-AF_SMC" , "sk_lock-AF_MAX" 226 }; 227 static const char *const af_family_slock_key_strings[AF_MAX+1] = { 228 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" , 229 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK", 230 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" , 231 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" , 232 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" , 233 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" , 234 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" , 235 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" , 236 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" , 237 "slock-27" , "slock-28" , "slock-AF_CAN" , 238 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" , 239 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" , 240 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" , 241 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_KCM" , 242 "slock-AF_QIPCRTR", "slock-AF_SMC" , "slock-AF_MAX" 243 }; 244 static const char *const af_family_clock_key_strings[AF_MAX+1] = { 245 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" , 246 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK", 247 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" , 248 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" , 249 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" , 250 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" , 251 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" , 252 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" , 253 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" , 254 "clock-27" , "clock-28" , "clock-AF_CAN" , 255 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" , 256 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" , 257 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" , 258 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_KCM" , 259 "clock-AF_QIPCRTR", "clock-AF_SMC" , "clock-AF_MAX" 260 }; 261 262 /* 263 * sk_callback_lock locking rules are per-address-family, 264 * so split the lock classes by using a per-AF key: 265 */ 266 static struct lock_class_key af_callback_keys[AF_MAX]; 267 268 /* Take into consideration the size of the struct sk_buff overhead in the 269 * determination of these values, since that is non-constant across 270 * platforms. This makes socket queueing behavior and performance 271 * not depend upon such differences. 272 */ 273 #define _SK_MEM_PACKETS 256 274 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 275 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 276 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 277 278 /* Run time adjustable parameters. */ 279 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX; 280 EXPORT_SYMBOL(sysctl_wmem_max); 281 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX; 282 EXPORT_SYMBOL(sysctl_rmem_max); 283 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX; 284 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX; 285 286 /* Maximal space eaten by iovec or ancillary data plus some space */ 287 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512); 288 EXPORT_SYMBOL(sysctl_optmem_max); 289 290 int sysctl_tstamp_allow_data __read_mostly = 1; 291 292 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE; 293 EXPORT_SYMBOL_GPL(memalloc_socks); 294 295 /** 296 * sk_set_memalloc - sets %SOCK_MEMALLOC 297 * @sk: socket to set it on 298 * 299 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves. 300 * It's the responsibility of the admin to adjust min_free_kbytes 301 * to meet the requirements 302 */ 303 void sk_set_memalloc(struct sock *sk) 304 { 305 sock_set_flag(sk, SOCK_MEMALLOC); 306 sk->sk_allocation |= __GFP_MEMALLOC; 307 static_key_slow_inc(&memalloc_socks); 308 } 309 EXPORT_SYMBOL_GPL(sk_set_memalloc); 310 311 void sk_clear_memalloc(struct sock *sk) 312 { 313 sock_reset_flag(sk, SOCK_MEMALLOC); 314 sk->sk_allocation &= ~__GFP_MEMALLOC; 315 static_key_slow_dec(&memalloc_socks); 316 317 /* 318 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward 319 * progress of swapping. SOCK_MEMALLOC may be cleared while 320 * it has rmem allocations due to the last swapfile being deactivated 321 * but there is a risk that the socket is unusable due to exceeding 322 * the rmem limits. Reclaim the reserves and obey rmem limits again. 323 */ 324 sk_mem_reclaim(sk); 325 } 326 EXPORT_SYMBOL_GPL(sk_clear_memalloc); 327 328 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 329 { 330 int ret; 331 unsigned long pflags = current->flags; 332 333 /* these should have been dropped before queueing */ 334 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC)); 335 336 current->flags |= PF_MEMALLOC; 337 ret = sk->sk_backlog_rcv(sk, skb); 338 tsk_restore_flags(current, pflags, PF_MEMALLOC); 339 340 return ret; 341 } 342 EXPORT_SYMBOL(__sk_backlog_rcv); 343 344 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen) 345 { 346 struct timeval tv; 347 348 if (optlen < sizeof(tv)) 349 return -EINVAL; 350 if (copy_from_user(&tv, optval, sizeof(tv))) 351 return -EFAULT; 352 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC) 353 return -EDOM; 354 355 if (tv.tv_sec < 0) { 356 static int warned __read_mostly; 357 358 *timeo_p = 0; 359 if (warned < 10 && net_ratelimit()) { 360 warned++; 361 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n", 362 __func__, current->comm, task_pid_nr(current)); 363 } 364 return 0; 365 } 366 *timeo_p = MAX_SCHEDULE_TIMEOUT; 367 if (tv.tv_sec == 0 && tv.tv_usec == 0) 368 return 0; 369 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1)) 370 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ); 371 return 0; 372 } 373 374 static void sock_warn_obsolete_bsdism(const char *name) 375 { 376 static int warned; 377 static char warncomm[TASK_COMM_LEN]; 378 if (strcmp(warncomm, current->comm) && warned < 5) { 379 strcpy(warncomm, current->comm); 380 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n", 381 warncomm, name); 382 warned++; 383 } 384 } 385 386 static bool sock_needs_netstamp(const struct sock *sk) 387 { 388 switch (sk->sk_family) { 389 case AF_UNSPEC: 390 case AF_UNIX: 391 return false; 392 default: 393 return true; 394 } 395 } 396 397 static void sock_disable_timestamp(struct sock *sk, unsigned long flags) 398 { 399 if (sk->sk_flags & flags) { 400 sk->sk_flags &= ~flags; 401 if (sock_needs_netstamp(sk) && 402 !(sk->sk_flags & SK_FLAGS_TIMESTAMP)) 403 net_disable_timestamp(); 404 } 405 } 406 407 408 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 409 { 410 unsigned long flags; 411 struct sk_buff_head *list = &sk->sk_receive_queue; 412 413 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { 414 atomic_inc(&sk->sk_drops); 415 trace_sock_rcvqueue_full(sk, skb); 416 return -ENOMEM; 417 } 418 419 if (!sk_rmem_schedule(sk, skb, skb->truesize)) { 420 atomic_inc(&sk->sk_drops); 421 return -ENOBUFS; 422 } 423 424 skb->dev = NULL; 425 skb_set_owner_r(skb, sk); 426 427 /* we escape from rcu protected region, make sure we dont leak 428 * a norefcounted dst 429 */ 430 skb_dst_force(skb); 431 432 spin_lock_irqsave(&list->lock, flags); 433 sock_skb_set_dropcount(sk, skb); 434 __skb_queue_tail(list, skb); 435 spin_unlock_irqrestore(&list->lock, flags); 436 437 if (!sock_flag(sk, SOCK_DEAD)) 438 sk->sk_data_ready(sk); 439 return 0; 440 } 441 EXPORT_SYMBOL(__sock_queue_rcv_skb); 442 443 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 444 { 445 int err; 446 447 err = sk_filter(sk, skb); 448 if (err) 449 return err; 450 451 return __sock_queue_rcv_skb(sk, skb); 452 } 453 EXPORT_SYMBOL(sock_queue_rcv_skb); 454 455 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, 456 const int nested, unsigned int trim_cap, bool refcounted) 457 { 458 int rc = NET_RX_SUCCESS; 459 460 if (sk_filter_trim_cap(sk, skb, trim_cap)) 461 goto discard_and_relse; 462 463 skb->dev = NULL; 464 465 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) { 466 atomic_inc(&sk->sk_drops); 467 goto discard_and_relse; 468 } 469 if (nested) 470 bh_lock_sock_nested(sk); 471 else 472 bh_lock_sock(sk); 473 if (!sock_owned_by_user(sk)) { 474 /* 475 * trylock + unlock semantics: 476 */ 477 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_); 478 479 rc = sk_backlog_rcv(sk, skb); 480 481 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); 482 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) { 483 bh_unlock_sock(sk); 484 atomic_inc(&sk->sk_drops); 485 goto discard_and_relse; 486 } 487 488 bh_unlock_sock(sk); 489 out: 490 if (refcounted) 491 sock_put(sk); 492 return rc; 493 discard_and_relse: 494 kfree_skb(skb); 495 goto out; 496 } 497 EXPORT_SYMBOL(__sk_receive_skb); 498 499 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie) 500 { 501 struct dst_entry *dst = __sk_dst_get(sk); 502 503 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 504 sk_tx_queue_clear(sk); 505 RCU_INIT_POINTER(sk->sk_dst_cache, NULL); 506 dst_release(dst); 507 return NULL; 508 } 509 510 return dst; 511 } 512 EXPORT_SYMBOL(__sk_dst_check); 513 514 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie) 515 { 516 struct dst_entry *dst = sk_dst_get(sk); 517 518 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) { 519 sk_dst_reset(sk); 520 dst_release(dst); 521 return NULL; 522 } 523 524 return dst; 525 } 526 EXPORT_SYMBOL(sk_dst_check); 527 528 static int sock_setbindtodevice(struct sock *sk, char __user *optval, 529 int optlen) 530 { 531 int ret = -ENOPROTOOPT; 532 #ifdef CONFIG_NETDEVICES 533 struct net *net = sock_net(sk); 534 char devname[IFNAMSIZ]; 535 int index; 536 537 /* Sorry... */ 538 ret = -EPERM; 539 if (!ns_capable(net->user_ns, CAP_NET_RAW)) 540 goto out; 541 542 ret = -EINVAL; 543 if (optlen < 0) 544 goto out; 545 546 /* Bind this socket to a particular device like "eth0", 547 * as specified in the passed interface name. If the 548 * name is "" or the option length is zero the socket 549 * is not bound. 550 */ 551 if (optlen > IFNAMSIZ - 1) 552 optlen = IFNAMSIZ - 1; 553 memset(devname, 0, sizeof(devname)); 554 555 ret = -EFAULT; 556 if (copy_from_user(devname, optval, optlen)) 557 goto out; 558 559 index = 0; 560 if (devname[0] != '\0') { 561 struct net_device *dev; 562 563 rcu_read_lock(); 564 dev = dev_get_by_name_rcu(net, devname); 565 if (dev) 566 index = dev->ifindex; 567 rcu_read_unlock(); 568 ret = -ENODEV; 569 if (!dev) 570 goto out; 571 } 572 573 lock_sock(sk); 574 sk->sk_bound_dev_if = index; 575 sk_dst_reset(sk); 576 release_sock(sk); 577 578 ret = 0; 579 580 out: 581 #endif 582 583 return ret; 584 } 585 586 static int sock_getbindtodevice(struct sock *sk, char __user *optval, 587 int __user *optlen, int len) 588 { 589 int ret = -ENOPROTOOPT; 590 #ifdef CONFIG_NETDEVICES 591 struct net *net = sock_net(sk); 592 char devname[IFNAMSIZ]; 593 594 if (sk->sk_bound_dev_if == 0) { 595 len = 0; 596 goto zero; 597 } 598 599 ret = -EINVAL; 600 if (len < IFNAMSIZ) 601 goto out; 602 603 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if); 604 if (ret) 605 goto out; 606 607 len = strlen(devname) + 1; 608 609 ret = -EFAULT; 610 if (copy_to_user(optval, devname, len)) 611 goto out; 612 613 zero: 614 ret = -EFAULT; 615 if (put_user(len, optlen)) 616 goto out; 617 618 ret = 0; 619 620 out: 621 #endif 622 623 return ret; 624 } 625 626 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool) 627 { 628 if (valbool) 629 sock_set_flag(sk, bit); 630 else 631 sock_reset_flag(sk, bit); 632 } 633 634 bool sk_mc_loop(struct sock *sk) 635 { 636 if (dev_recursion_level()) 637 return false; 638 if (!sk) 639 return true; 640 switch (sk->sk_family) { 641 case AF_INET: 642 return inet_sk(sk)->mc_loop; 643 #if IS_ENABLED(CONFIG_IPV6) 644 case AF_INET6: 645 return inet6_sk(sk)->mc_loop; 646 #endif 647 } 648 WARN_ON(1); 649 return true; 650 } 651 EXPORT_SYMBOL(sk_mc_loop); 652 653 /* 654 * This is meant for all protocols to use and covers goings on 655 * at the socket level. Everything here is generic. 656 */ 657 658 int sock_setsockopt(struct socket *sock, int level, int optname, 659 char __user *optval, unsigned int optlen) 660 { 661 struct sock *sk = sock->sk; 662 int val; 663 int valbool; 664 struct linger ling; 665 int ret = 0; 666 667 /* 668 * Options without arguments 669 */ 670 671 if (optname == SO_BINDTODEVICE) 672 return sock_setbindtodevice(sk, optval, optlen); 673 674 if (optlen < sizeof(int)) 675 return -EINVAL; 676 677 if (get_user(val, (int __user *)optval)) 678 return -EFAULT; 679 680 valbool = val ? 1 : 0; 681 682 lock_sock(sk); 683 684 switch (optname) { 685 case SO_DEBUG: 686 if (val && !capable(CAP_NET_ADMIN)) 687 ret = -EACCES; 688 else 689 sock_valbool_flag(sk, SOCK_DBG, valbool); 690 break; 691 case SO_REUSEADDR: 692 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE); 693 break; 694 case SO_REUSEPORT: 695 sk->sk_reuseport = valbool; 696 break; 697 case SO_TYPE: 698 case SO_PROTOCOL: 699 case SO_DOMAIN: 700 case SO_ERROR: 701 ret = -ENOPROTOOPT; 702 break; 703 case SO_DONTROUTE: 704 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool); 705 break; 706 case SO_BROADCAST: 707 sock_valbool_flag(sk, SOCK_BROADCAST, valbool); 708 break; 709 case SO_SNDBUF: 710 /* Don't error on this BSD doesn't and if you think 711 * about it this is right. Otherwise apps have to 712 * play 'guess the biggest size' games. RCVBUF/SNDBUF 713 * are treated in BSD as hints 714 */ 715 val = min_t(u32, val, sysctl_wmem_max); 716 set_sndbuf: 717 sk->sk_userlocks |= SOCK_SNDBUF_LOCK; 718 sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF); 719 /* Wake up sending tasks if we upped the value. */ 720 sk->sk_write_space(sk); 721 break; 722 723 case SO_SNDBUFFORCE: 724 if (!capable(CAP_NET_ADMIN)) { 725 ret = -EPERM; 726 break; 727 } 728 goto set_sndbuf; 729 730 case SO_RCVBUF: 731 /* Don't error on this BSD doesn't and if you think 732 * about it this is right. Otherwise apps have to 733 * play 'guess the biggest size' games. RCVBUF/SNDBUF 734 * are treated in BSD as hints 735 */ 736 val = min_t(u32, val, sysctl_rmem_max); 737 set_rcvbuf: 738 sk->sk_userlocks |= SOCK_RCVBUF_LOCK; 739 /* 740 * We double it on the way in to account for 741 * "struct sk_buff" etc. overhead. Applications 742 * assume that the SO_RCVBUF setting they make will 743 * allow that much actual data to be received on that 744 * socket. 745 * 746 * Applications are unaware that "struct sk_buff" and 747 * other overheads allocate from the receive buffer 748 * during socket buffer allocation. 749 * 750 * And after considering the possible alternatives, 751 * returning the value we actually used in getsockopt 752 * is the most desirable behavior. 753 */ 754 sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF); 755 break; 756 757 case SO_RCVBUFFORCE: 758 if (!capable(CAP_NET_ADMIN)) { 759 ret = -EPERM; 760 break; 761 } 762 goto set_rcvbuf; 763 764 case SO_KEEPALIVE: 765 if (sk->sk_prot->keepalive) 766 sk->sk_prot->keepalive(sk, valbool); 767 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); 768 break; 769 770 case SO_OOBINLINE: 771 sock_valbool_flag(sk, SOCK_URGINLINE, valbool); 772 break; 773 774 case SO_NO_CHECK: 775 sk->sk_no_check_tx = valbool; 776 break; 777 778 case SO_PRIORITY: 779 if ((val >= 0 && val <= 6) || 780 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 781 sk->sk_priority = val; 782 else 783 ret = -EPERM; 784 break; 785 786 case SO_LINGER: 787 if (optlen < sizeof(ling)) { 788 ret = -EINVAL; /* 1003.1g */ 789 break; 790 } 791 if (copy_from_user(&ling, optval, sizeof(ling))) { 792 ret = -EFAULT; 793 break; 794 } 795 if (!ling.l_onoff) 796 sock_reset_flag(sk, SOCK_LINGER); 797 else { 798 #if (BITS_PER_LONG == 32) 799 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) 800 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; 801 else 802 #endif 803 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; 804 sock_set_flag(sk, SOCK_LINGER); 805 } 806 break; 807 808 case SO_BSDCOMPAT: 809 sock_warn_obsolete_bsdism("setsockopt"); 810 break; 811 812 case SO_PASSCRED: 813 if (valbool) 814 set_bit(SOCK_PASSCRED, &sock->flags); 815 else 816 clear_bit(SOCK_PASSCRED, &sock->flags); 817 break; 818 819 case SO_TIMESTAMP: 820 case SO_TIMESTAMPNS: 821 if (valbool) { 822 if (optname == SO_TIMESTAMP) 823 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 824 else 825 sock_set_flag(sk, SOCK_RCVTSTAMPNS); 826 sock_set_flag(sk, SOCK_RCVTSTAMP); 827 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 828 } else { 829 sock_reset_flag(sk, SOCK_RCVTSTAMP); 830 sock_reset_flag(sk, SOCK_RCVTSTAMPNS); 831 } 832 break; 833 834 case SO_TIMESTAMPING: 835 if (val & ~SOF_TIMESTAMPING_MASK) { 836 ret = -EINVAL; 837 break; 838 } 839 840 if (val & SOF_TIMESTAMPING_OPT_ID && 841 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) { 842 if (sk->sk_protocol == IPPROTO_TCP && 843 sk->sk_type == SOCK_STREAM) { 844 if ((1 << sk->sk_state) & 845 (TCPF_CLOSE | TCPF_LISTEN)) { 846 ret = -EINVAL; 847 break; 848 } 849 sk->sk_tskey = tcp_sk(sk)->snd_una; 850 } else { 851 sk->sk_tskey = 0; 852 } 853 } 854 855 if (val & SOF_TIMESTAMPING_OPT_STATS && 856 !(val & SOF_TIMESTAMPING_OPT_TSONLY)) { 857 ret = -EINVAL; 858 break; 859 } 860 861 sk->sk_tsflags = val; 862 if (val & SOF_TIMESTAMPING_RX_SOFTWARE) 863 sock_enable_timestamp(sk, 864 SOCK_TIMESTAMPING_RX_SOFTWARE); 865 else 866 sock_disable_timestamp(sk, 867 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)); 868 break; 869 870 case SO_RCVLOWAT: 871 if (val < 0) 872 val = INT_MAX; 873 sk->sk_rcvlowat = val ? : 1; 874 break; 875 876 case SO_RCVTIMEO: 877 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); 878 break; 879 880 case SO_SNDTIMEO: 881 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); 882 break; 883 884 case SO_ATTACH_FILTER: 885 ret = -EINVAL; 886 if (optlen == sizeof(struct sock_fprog)) { 887 struct sock_fprog fprog; 888 889 ret = -EFAULT; 890 if (copy_from_user(&fprog, optval, sizeof(fprog))) 891 break; 892 893 ret = sk_attach_filter(&fprog, sk); 894 } 895 break; 896 897 case SO_ATTACH_BPF: 898 ret = -EINVAL; 899 if (optlen == sizeof(u32)) { 900 u32 ufd; 901 902 ret = -EFAULT; 903 if (copy_from_user(&ufd, optval, sizeof(ufd))) 904 break; 905 906 ret = sk_attach_bpf(ufd, sk); 907 } 908 break; 909 910 case SO_ATTACH_REUSEPORT_CBPF: 911 ret = -EINVAL; 912 if (optlen == sizeof(struct sock_fprog)) { 913 struct sock_fprog fprog; 914 915 ret = -EFAULT; 916 if (copy_from_user(&fprog, optval, sizeof(fprog))) 917 break; 918 919 ret = sk_reuseport_attach_filter(&fprog, sk); 920 } 921 break; 922 923 case SO_ATTACH_REUSEPORT_EBPF: 924 ret = -EINVAL; 925 if (optlen == sizeof(u32)) { 926 u32 ufd; 927 928 ret = -EFAULT; 929 if (copy_from_user(&ufd, optval, sizeof(ufd))) 930 break; 931 932 ret = sk_reuseport_attach_bpf(ufd, sk); 933 } 934 break; 935 936 case SO_DETACH_FILTER: 937 ret = sk_detach_filter(sk); 938 break; 939 940 case SO_LOCK_FILTER: 941 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool) 942 ret = -EPERM; 943 else 944 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool); 945 break; 946 947 case SO_PASSSEC: 948 if (valbool) 949 set_bit(SOCK_PASSSEC, &sock->flags); 950 else 951 clear_bit(SOCK_PASSSEC, &sock->flags); 952 break; 953 case SO_MARK: 954 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 955 ret = -EPERM; 956 else 957 sk->sk_mark = val; 958 break; 959 960 case SO_RXQ_OVFL: 961 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool); 962 break; 963 964 case SO_WIFI_STATUS: 965 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool); 966 break; 967 968 case SO_PEEK_OFF: 969 if (sock->ops->set_peek_off) 970 ret = sock->ops->set_peek_off(sk, val); 971 else 972 ret = -EOPNOTSUPP; 973 break; 974 975 case SO_NOFCS: 976 sock_valbool_flag(sk, SOCK_NOFCS, valbool); 977 break; 978 979 case SO_SELECT_ERR_QUEUE: 980 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool); 981 break; 982 983 #ifdef CONFIG_NET_RX_BUSY_POLL 984 case SO_BUSY_POLL: 985 /* allow unprivileged users to decrease the value */ 986 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN)) 987 ret = -EPERM; 988 else { 989 if (val < 0) 990 ret = -EINVAL; 991 else 992 sk->sk_ll_usec = val; 993 } 994 break; 995 #endif 996 997 case SO_MAX_PACING_RATE: 998 sk->sk_max_pacing_rate = val; 999 sk->sk_pacing_rate = min(sk->sk_pacing_rate, 1000 sk->sk_max_pacing_rate); 1001 break; 1002 1003 case SO_INCOMING_CPU: 1004 sk->sk_incoming_cpu = val; 1005 break; 1006 1007 case SO_CNX_ADVICE: 1008 if (val == 1) 1009 dst_negative_advice(sk); 1010 break; 1011 default: 1012 ret = -ENOPROTOOPT; 1013 break; 1014 } 1015 release_sock(sk); 1016 return ret; 1017 } 1018 EXPORT_SYMBOL(sock_setsockopt); 1019 1020 1021 static void cred_to_ucred(struct pid *pid, const struct cred *cred, 1022 struct ucred *ucred) 1023 { 1024 ucred->pid = pid_vnr(pid); 1025 ucred->uid = ucred->gid = -1; 1026 if (cred) { 1027 struct user_namespace *current_ns = current_user_ns(); 1028 1029 ucred->uid = from_kuid_munged(current_ns, cred->euid); 1030 ucred->gid = from_kgid_munged(current_ns, cred->egid); 1031 } 1032 } 1033 1034 int sock_getsockopt(struct socket *sock, int level, int optname, 1035 char __user *optval, int __user *optlen) 1036 { 1037 struct sock *sk = sock->sk; 1038 1039 union { 1040 int val; 1041 struct linger ling; 1042 struct timeval tm; 1043 } v; 1044 1045 int lv = sizeof(int); 1046 int len; 1047 1048 if (get_user(len, optlen)) 1049 return -EFAULT; 1050 if (len < 0) 1051 return -EINVAL; 1052 1053 memset(&v, 0, sizeof(v)); 1054 1055 switch (optname) { 1056 case SO_DEBUG: 1057 v.val = sock_flag(sk, SOCK_DBG); 1058 break; 1059 1060 case SO_DONTROUTE: 1061 v.val = sock_flag(sk, SOCK_LOCALROUTE); 1062 break; 1063 1064 case SO_BROADCAST: 1065 v.val = sock_flag(sk, SOCK_BROADCAST); 1066 break; 1067 1068 case SO_SNDBUF: 1069 v.val = sk->sk_sndbuf; 1070 break; 1071 1072 case SO_RCVBUF: 1073 v.val = sk->sk_rcvbuf; 1074 break; 1075 1076 case SO_REUSEADDR: 1077 v.val = sk->sk_reuse; 1078 break; 1079 1080 case SO_REUSEPORT: 1081 v.val = sk->sk_reuseport; 1082 break; 1083 1084 case SO_KEEPALIVE: 1085 v.val = sock_flag(sk, SOCK_KEEPOPEN); 1086 break; 1087 1088 case SO_TYPE: 1089 v.val = sk->sk_type; 1090 break; 1091 1092 case SO_PROTOCOL: 1093 v.val = sk->sk_protocol; 1094 break; 1095 1096 case SO_DOMAIN: 1097 v.val = sk->sk_family; 1098 break; 1099 1100 case SO_ERROR: 1101 v.val = -sock_error(sk); 1102 if (v.val == 0) 1103 v.val = xchg(&sk->sk_err_soft, 0); 1104 break; 1105 1106 case SO_OOBINLINE: 1107 v.val = sock_flag(sk, SOCK_URGINLINE); 1108 break; 1109 1110 case SO_NO_CHECK: 1111 v.val = sk->sk_no_check_tx; 1112 break; 1113 1114 case SO_PRIORITY: 1115 v.val = sk->sk_priority; 1116 break; 1117 1118 case SO_LINGER: 1119 lv = sizeof(v.ling); 1120 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER); 1121 v.ling.l_linger = sk->sk_lingertime / HZ; 1122 break; 1123 1124 case SO_BSDCOMPAT: 1125 sock_warn_obsolete_bsdism("getsockopt"); 1126 break; 1127 1128 case SO_TIMESTAMP: 1129 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && 1130 !sock_flag(sk, SOCK_RCVTSTAMPNS); 1131 break; 1132 1133 case SO_TIMESTAMPNS: 1134 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS); 1135 break; 1136 1137 case SO_TIMESTAMPING: 1138 v.val = sk->sk_tsflags; 1139 break; 1140 1141 case SO_RCVTIMEO: 1142 lv = sizeof(struct timeval); 1143 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { 1144 v.tm.tv_sec = 0; 1145 v.tm.tv_usec = 0; 1146 } else { 1147 v.tm.tv_sec = sk->sk_rcvtimeo / HZ; 1148 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; 1149 } 1150 break; 1151 1152 case SO_SNDTIMEO: 1153 lv = sizeof(struct timeval); 1154 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { 1155 v.tm.tv_sec = 0; 1156 v.tm.tv_usec = 0; 1157 } else { 1158 v.tm.tv_sec = sk->sk_sndtimeo / HZ; 1159 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; 1160 } 1161 break; 1162 1163 case SO_RCVLOWAT: 1164 v.val = sk->sk_rcvlowat; 1165 break; 1166 1167 case SO_SNDLOWAT: 1168 v.val = 1; 1169 break; 1170 1171 case SO_PASSCRED: 1172 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags); 1173 break; 1174 1175 case SO_PEERCRED: 1176 { 1177 struct ucred peercred; 1178 if (len > sizeof(peercred)) 1179 len = sizeof(peercred); 1180 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred); 1181 if (copy_to_user(optval, &peercred, len)) 1182 return -EFAULT; 1183 goto lenout; 1184 } 1185 1186 case SO_PEERNAME: 1187 { 1188 char address[128]; 1189 1190 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) 1191 return -ENOTCONN; 1192 if (lv < len) 1193 return -EINVAL; 1194 if (copy_to_user(optval, address, len)) 1195 return -EFAULT; 1196 goto lenout; 1197 } 1198 1199 /* Dubious BSD thing... Probably nobody even uses it, but 1200 * the UNIX standard wants it for whatever reason... -DaveM 1201 */ 1202 case SO_ACCEPTCONN: 1203 v.val = sk->sk_state == TCP_LISTEN; 1204 break; 1205 1206 case SO_PASSSEC: 1207 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags); 1208 break; 1209 1210 case SO_PEERSEC: 1211 return security_socket_getpeersec_stream(sock, optval, optlen, len); 1212 1213 case SO_MARK: 1214 v.val = sk->sk_mark; 1215 break; 1216 1217 case SO_RXQ_OVFL: 1218 v.val = sock_flag(sk, SOCK_RXQ_OVFL); 1219 break; 1220 1221 case SO_WIFI_STATUS: 1222 v.val = sock_flag(sk, SOCK_WIFI_STATUS); 1223 break; 1224 1225 case SO_PEEK_OFF: 1226 if (!sock->ops->set_peek_off) 1227 return -EOPNOTSUPP; 1228 1229 v.val = sk->sk_peek_off; 1230 break; 1231 case SO_NOFCS: 1232 v.val = sock_flag(sk, SOCK_NOFCS); 1233 break; 1234 1235 case SO_BINDTODEVICE: 1236 return sock_getbindtodevice(sk, optval, optlen, len); 1237 1238 case SO_GET_FILTER: 1239 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len); 1240 if (len < 0) 1241 return len; 1242 1243 goto lenout; 1244 1245 case SO_LOCK_FILTER: 1246 v.val = sock_flag(sk, SOCK_FILTER_LOCKED); 1247 break; 1248 1249 case SO_BPF_EXTENSIONS: 1250 v.val = bpf_tell_extensions(); 1251 break; 1252 1253 case SO_SELECT_ERR_QUEUE: 1254 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE); 1255 break; 1256 1257 #ifdef CONFIG_NET_RX_BUSY_POLL 1258 case SO_BUSY_POLL: 1259 v.val = sk->sk_ll_usec; 1260 break; 1261 #endif 1262 1263 case SO_MAX_PACING_RATE: 1264 v.val = sk->sk_max_pacing_rate; 1265 break; 1266 1267 case SO_INCOMING_CPU: 1268 v.val = sk->sk_incoming_cpu; 1269 break; 1270 1271 default: 1272 /* We implement the SO_SNDLOWAT etc to not be settable 1273 * (1003.1g 7). 1274 */ 1275 return -ENOPROTOOPT; 1276 } 1277 1278 if (len > lv) 1279 len = lv; 1280 if (copy_to_user(optval, &v, len)) 1281 return -EFAULT; 1282 lenout: 1283 if (put_user(len, optlen)) 1284 return -EFAULT; 1285 return 0; 1286 } 1287 1288 /* 1289 * Initialize an sk_lock. 1290 * 1291 * (We also register the sk_lock with the lock validator.) 1292 */ 1293 static inline void sock_lock_init(struct sock *sk) 1294 { 1295 sock_lock_init_class_and_name(sk, 1296 af_family_slock_key_strings[sk->sk_family], 1297 af_family_slock_keys + sk->sk_family, 1298 af_family_key_strings[sk->sk_family], 1299 af_family_keys + sk->sk_family); 1300 } 1301 1302 /* 1303 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet, 1304 * even temporarly, because of RCU lookups. sk_node should also be left as is. 1305 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end 1306 */ 1307 static void sock_copy(struct sock *nsk, const struct sock *osk) 1308 { 1309 #ifdef CONFIG_SECURITY_NETWORK 1310 void *sptr = nsk->sk_security; 1311 #endif 1312 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin)); 1313 1314 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end, 1315 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end)); 1316 1317 #ifdef CONFIG_SECURITY_NETWORK 1318 nsk->sk_security = sptr; 1319 security_sk_clone(osk, nsk); 1320 #endif 1321 } 1322 1323 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority, 1324 int family) 1325 { 1326 struct sock *sk; 1327 struct kmem_cache *slab; 1328 1329 slab = prot->slab; 1330 if (slab != NULL) { 1331 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO); 1332 if (!sk) 1333 return sk; 1334 if (priority & __GFP_ZERO) 1335 sk_prot_clear_nulls(sk, prot->obj_size); 1336 } else 1337 sk = kmalloc(prot->obj_size, priority); 1338 1339 if (sk != NULL) { 1340 kmemcheck_annotate_bitfield(sk, flags); 1341 1342 if (security_sk_alloc(sk, family, priority)) 1343 goto out_free; 1344 1345 if (!try_module_get(prot->owner)) 1346 goto out_free_sec; 1347 sk_tx_queue_clear(sk); 1348 } 1349 1350 return sk; 1351 1352 out_free_sec: 1353 security_sk_free(sk); 1354 out_free: 1355 if (slab != NULL) 1356 kmem_cache_free(slab, sk); 1357 else 1358 kfree(sk); 1359 return NULL; 1360 } 1361 1362 static void sk_prot_free(struct proto *prot, struct sock *sk) 1363 { 1364 struct kmem_cache *slab; 1365 struct module *owner; 1366 1367 owner = prot->owner; 1368 slab = prot->slab; 1369 1370 cgroup_sk_free(&sk->sk_cgrp_data); 1371 mem_cgroup_sk_free(sk); 1372 security_sk_free(sk); 1373 if (slab != NULL) 1374 kmem_cache_free(slab, sk); 1375 else 1376 kfree(sk); 1377 module_put(owner); 1378 } 1379 1380 /** 1381 * sk_alloc - All socket objects are allocated here 1382 * @net: the applicable net namespace 1383 * @family: protocol family 1384 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1385 * @prot: struct proto associated with this new sock instance 1386 * @kern: is this to be a kernel socket? 1387 */ 1388 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1389 struct proto *prot, int kern) 1390 { 1391 struct sock *sk; 1392 1393 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family); 1394 if (sk) { 1395 sk->sk_family = family; 1396 /* 1397 * See comment in struct sock definition to understand 1398 * why we need sk_prot_creator -acme 1399 */ 1400 sk->sk_prot = sk->sk_prot_creator = prot; 1401 sock_lock_init(sk); 1402 sk->sk_net_refcnt = kern ? 0 : 1; 1403 if (likely(sk->sk_net_refcnt)) 1404 get_net(net); 1405 sock_net_set(sk, net); 1406 atomic_set(&sk->sk_wmem_alloc, 1); 1407 1408 mem_cgroup_sk_alloc(sk); 1409 cgroup_sk_alloc(&sk->sk_cgrp_data); 1410 sock_update_classid(&sk->sk_cgrp_data); 1411 sock_update_netprioidx(&sk->sk_cgrp_data); 1412 } 1413 1414 return sk; 1415 } 1416 EXPORT_SYMBOL(sk_alloc); 1417 1418 /* Sockets having SOCK_RCU_FREE will call this function after one RCU 1419 * grace period. This is the case for UDP sockets and TCP listeners. 1420 */ 1421 static void __sk_destruct(struct rcu_head *head) 1422 { 1423 struct sock *sk = container_of(head, struct sock, sk_rcu); 1424 struct sk_filter *filter; 1425 1426 if (sk->sk_destruct) 1427 sk->sk_destruct(sk); 1428 1429 filter = rcu_dereference_check(sk->sk_filter, 1430 atomic_read(&sk->sk_wmem_alloc) == 0); 1431 if (filter) { 1432 sk_filter_uncharge(sk, filter); 1433 RCU_INIT_POINTER(sk->sk_filter, NULL); 1434 } 1435 if (rcu_access_pointer(sk->sk_reuseport_cb)) 1436 reuseport_detach_sock(sk); 1437 1438 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP); 1439 1440 if (atomic_read(&sk->sk_omem_alloc)) 1441 pr_debug("%s: optmem leakage (%d bytes) detected\n", 1442 __func__, atomic_read(&sk->sk_omem_alloc)); 1443 1444 if (sk->sk_peer_cred) 1445 put_cred(sk->sk_peer_cred); 1446 put_pid(sk->sk_peer_pid); 1447 if (likely(sk->sk_net_refcnt)) 1448 put_net(sock_net(sk)); 1449 sk_prot_free(sk->sk_prot_creator, sk); 1450 } 1451 1452 void sk_destruct(struct sock *sk) 1453 { 1454 if (sock_flag(sk, SOCK_RCU_FREE)) 1455 call_rcu(&sk->sk_rcu, __sk_destruct); 1456 else 1457 __sk_destruct(&sk->sk_rcu); 1458 } 1459 1460 static void __sk_free(struct sock *sk) 1461 { 1462 if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt)) 1463 sock_diag_broadcast_destroy(sk); 1464 else 1465 sk_destruct(sk); 1466 } 1467 1468 void sk_free(struct sock *sk) 1469 { 1470 /* 1471 * We subtract one from sk_wmem_alloc and can know if 1472 * some packets are still in some tx queue. 1473 * If not null, sock_wfree() will call __sk_free(sk) later 1474 */ 1475 if (atomic_dec_and_test(&sk->sk_wmem_alloc)) 1476 __sk_free(sk); 1477 } 1478 EXPORT_SYMBOL(sk_free); 1479 1480 /** 1481 * sk_clone_lock - clone a socket, and lock its clone 1482 * @sk: the socket to clone 1483 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) 1484 * 1485 * Caller must unlock socket even in error path (bh_unlock_sock(newsk)) 1486 */ 1487 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) 1488 { 1489 struct sock *newsk; 1490 bool is_charged = true; 1491 1492 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family); 1493 if (newsk != NULL) { 1494 struct sk_filter *filter; 1495 1496 sock_copy(newsk, sk); 1497 1498 /* SANITY */ 1499 if (likely(newsk->sk_net_refcnt)) 1500 get_net(sock_net(newsk)); 1501 sk_node_init(&newsk->sk_node); 1502 sock_lock_init(newsk); 1503 bh_lock_sock(newsk); 1504 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; 1505 newsk->sk_backlog.len = 0; 1506 1507 atomic_set(&newsk->sk_rmem_alloc, 0); 1508 /* 1509 * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) 1510 */ 1511 atomic_set(&newsk->sk_wmem_alloc, 1); 1512 atomic_set(&newsk->sk_omem_alloc, 0); 1513 skb_queue_head_init(&newsk->sk_receive_queue); 1514 skb_queue_head_init(&newsk->sk_write_queue); 1515 1516 rwlock_init(&newsk->sk_callback_lock); 1517 lockdep_set_class_and_name(&newsk->sk_callback_lock, 1518 af_callback_keys + newsk->sk_family, 1519 af_family_clock_key_strings[newsk->sk_family]); 1520 1521 newsk->sk_dst_cache = NULL; 1522 newsk->sk_wmem_queued = 0; 1523 newsk->sk_forward_alloc = 0; 1524 atomic_set(&newsk->sk_drops, 0); 1525 newsk->sk_send_head = NULL; 1526 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; 1527 1528 sock_reset_flag(newsk, SOCK_DONE); 1529 skb_queue_head_init(&newsk->sk_error_queue); 1530 1531 filter = rcu_dereference_protected(newsk->sk_filter, 1); 1532 if (filter != NULL) 1533 /* though it's an empty new sock, the charging may fail 1534 * if sysctl_optmem_max was changed between creation of 1535 * original socket and cloning 1536 */ 1537 is_charged = sk_filter_charge(newsk, filter); 1538 1539 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) { 1540 /* It is still raw copy of parent, so invalidate 1541 * destructor and make plain sk_free() */ 1542 newsk->sk_destruct = NULL; 1543 bh_unlock_sock(newsk); 1544 sk_free(newsk); 1545 newsk = NULL; 1546 goto out; 1547 } 1548 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL); 1549 1550 newsk->sk_err = 0; 1551 newsk->sk_err_soft = 0; 1552 newsk->sk_priority = 0; 1553 newsk->sk_incoming_cpu = raw_smp_processor_id(); 1554 atomic64_set(&newsk->sk_cookie, 0); 1555 1556 mem_cgroup_sk_alloc(newsk); 1557 cgroup_sk_alloc(&newsk->sk_cgrp_data); 1558 1559 /* 1560 * Before updating sk_refcnt, we must commit prior changes to memory 1561 * (Documentation/RCU/rculist_nulls.txt for details) 1562 */ 1563 smp_wmb(); 1564 atomic_set(&newsk->sk_refcnt, 2); 1565 1566 /* 1567 * Increment the counter in the same struct proto as the master 1568 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that 1569 * is the same as sk->sk_prot->socks, as this field was copied 1570 * with memcpy). 1571 * 1572 * This _changes_ the previous behaviour, where 1573 * tcp_create_openreq_child always was incrementing the 1574 * equivalent to tcp_prot->socks (inet_sock_nr), so this have 1575 * to be taken into account in all callers. -acme 1576 */ 1577 sk_refcnt_debug_inc(newsk); 1578 sk_set_socket(newsk, NULL); 1579 newsk->sk_wq = NULL; 1580 1581 if (newsk->sk_prot->sockets_allocated) 1582 sk_sockets_allocated_inc(newsk); 1583 1584 if (sock_needs_netstamp(sk) && 1585 newsk->sk_flags & SK_FLAGS_TIMESTAMP) 1586 net_enable_timestamp(); 1587 } 1588 out: 1589 return newsk; 1590 } 1591 EXPORT_SYMBOL_GPL(sk_clone_lock); 1592 1593 void sk_setup_caps(struct sock *sk, struct dst_entry *dst) 1594 { 1595 u32 max_segs = 1; 1596 1597 sk_dst_set(sk, dst); 1598 sk->sk_route_caps = dst->dev->features; 1599 if (sk->sk_route_caps & NETIF_F_GSO) 1600 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE; 1601 sk->sk_route_caps &= ~sk->sk_route_nocaps; 1602 if (sk_can_gso(sk)) { 1603 if (dst->header_len) { 1604 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 1605 } else { 1606 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM; 1607 sk->sk_gso_max_size = dst->dev->gso_max_size; 1608 max_segs = max_t(u32, dst->dev->gso_max_segs, 1); 1609 } 1610 } 1611 sk->sk_gso_max_segs = max_segs; 1612 } 1613 EXPORT_SYMBOL_GPL(sk_setup_caps); 1614 1615 /* 1616 * Simple resource managers for sockets. 1617 */ 1618 1619 1620 /* 1621 * Write buffer destructor automatically called from kfree_skb. 1622 */ 1623 void sock_wfree(struct sk_buff *skb) 1624 { 1625 struct sock *sk = skb->sk; 1626 unsigned int len = skb->truesize; 1627 1628 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) { 1629 /* 1630 * Keep a reference on sk_wmem_alloc, this will be released 1631 * after sk_write_space() call 1632 */ 1633 atomic_sub(len - 1, &sk->sk_wmem_alloc); 1634 sk->sk_write_space(sk); 1635 len = 1; 1636 } 1637 /* 1638 * if sk_wmem_alloc reaches 0, we must finish what sk_free() 1639 * could not do because of in-flight packets 1640 */ 1641 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc)) 1642 __sk_free(sk); 1643 } 1644 EXPORT_SYMBOL(sock_wfree); 1645 1646 /* This variant of sock_wfree() is used by TCP, 1647 * since it sets SOCK_USE_WRITE_QUEUE. 1648 */ 1649 void __sock_wfree(struct sk_buff *skb) 1650 { 1651 struct sock *sk = skb->sk; 1652 1653 if (atomic_sub_and_test(skb->truesize, &sk->sk_wmem_alloc)) 1654 __sk_free(sk); 1655 } 1656 1657 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk) 1658 { 1659 skb_orphan(skb); 1660 skb->sk = sk; 1661 #ifdef CONFIG_INET 1662 if (unlikely(!sk_fullsock(sk))) { 1663 skb->destructor = sock_edemux; 1664 sock_hold(sk); 1665 return; 1666 } 1667 #endif 1668 skb->destructor = sock_wfree; 1669 skb_set_hash_from_sk(skb, sk); 1670 /* 1671 * We used to take a refcount on sk, but following operation 1672 * is enough to guarantee sk_free() wont free this sock until 1673 * all in-flight packets are completed 1674 */ 1675 atomic_add(skb->truesize, &sk->sk_wmem_alloc); 1676 } 1677 EXPORT_SYMBOL(skb_set_owner_w); 1678 1679 /* This helper is used by netem, as it can hold packets in its 1680 * delay queue. We want to allow the owner socket to send more 1681 * packets, as if they were already TX completed by a typical driver. 1682 * But we also want to keep skb->sk set because some packet schedulers 1683 * rely on it (sch_fq for example). So we set skb->truesize to a small 1684 * amount (1) and decrease sk_wmem_alloc accordingly. 1685 */ 1686 void skb_orphan_partial(struct sk_buff *skb) 1687 { 1688 /* If this skb is a TCP pure ACK or already went here, 1689 * we have nothing to do. 2 is already a very small truesize. 1690 */ 1691 if (skb->truesize <= 2) 1692 return; 1693 1694 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc, 1695 * so we do not completely orphan skb, but transfert all 1696 * accounted bytes but one, to avoid unexpected reorders. 1697 */ 1698 if (skb->destructor == sock_wfree 1699 #ifdef CONFIG_INET 1700 || skb->destructor == tcp_wfree 1701 #endif 1702 ) { 1703 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc); 1704 skb->truesize = 1; 1705 } else { 1706 skb_orphan(skb); 1707 } 1708 } 1709 EXPORT_SYMBOL(skb_orphan_partial); 1710 1711 /* 1712 * Read buffer destructor automatically called from kfree_skb. 1713 */ 1714 void sock_rfree(struct sk_buff *skb) 1715 { 1716 struct sock *sk = skb->sk; 1717 unsigned int len = skb->truesize; 1718 1719 atomic_sub(len, &sk->sk_rmem_alloc); 1720 sk_mem_uncharge(sk, len); 1721 } 1722 EXPORT_SYMBOL(sock_rfree); 1723 1724 /* 1725 * Buffer destructor for skbs that are not used directly in read or write 1726 * path, e.g. for error handler skbs. Automatically called from kfree_skb. 1727 */ 1728 void sock_efree(struct sk_buff *skb) 1729 { 1730 sock_put(skb->sk); 1731 } 1732 EXPORT_SYMBOL(sock_efree); 1733 1734 kuid_t sock_i_uid(struct sock *sk) 1735 { 1736 kuid_t uid; 1737 1738 read_lock_bh(&sk->sk_callback_lock); 1739 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID; 1740 read_unlock_bh(&sk->sk_callback_lock); 1741 return uid; 1742 } 1743 EXPORT_SYMBOL(sock_i_uid); 1744 1745 unsigned long sock_i_ino(struct sock *sk) 1746 { 1747 unsigned long ino; 1748 1749 read_lock_bh(&sk->sk_callback_lock); 1750 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; 1751 read_unlock_bh(&sk->sk_callback_lock); 1752 return ino; 1753 } 1754 EXPORT_SYMBOL(sock_i_ino); 1755 1756 /* 1757 * Allocate a skb from the socket's send buffer. 1758 */ 1759 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1760 gfp_t priority) 1761 { 1762 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { 1763 struct sk_buff *skb = alloc_skb(size, priority); 1764 if (skb) { 1765 skb_set_owner_w(skb, sk); 1766 return skb; 1767 } 1768 } 1769 return NULL; 1770 } 1771 EXPORT_SYMBOL(sock_wmalloc); 1772 1773 /* 1774 * Allocate a memory block from the socket's option memory buffer. 1775 */ 1776 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) 1777 { 1778 if ((unsigned int)size <= sysctl_optmem_max && 1779 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { 1780 void *mem; 1781 /* First do the add, to avoid the race if kmalloc 1782 * might sleep. 1783 */ 1784 atomic_add(size, &sk->sk_omem_alloc); 1785 mem = kmalloc(size, priority); 1786 if (mem) 1787 return mem; 1788 atomic_sub(size, &sk->sk_omem_alloc); 1789 } 1790 return NULL; 1791 } 1792 EXPORT_SYMBOL(sock_kmalloc); 1793 1794 /* Free an option memory block. Note, we actually want the inline 1795 * here as this allows gcc to detect the nullify and fold away the 1796 * condition entirely. 1797 */ 1798 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size, 1799 const bool nullify) 1800 { 1801 if (WARN_ON_ONCE(!mem)) 1802 return; 1803 if (nullify) 1804 kzfree(mem); 1805 else 1806 kfree(mem); 1807 atomic_sub(size, &sk->sk_omem_alloc); 1808 } 1809 1810 void sock_kfree_s(struct sock *sk, void *mem, int size) 1811 { 1812 __sock_kfree_s(sk, mem, size, false); 1813 } 1814 EXPORT_SYMBOL(sock_kfree_s); 1815 1816 void sock_kzfree_s(struct sock *sk, void *mem, int size) 1817 { 1818 __sock_kfree_s(sk, mem, size, true); 1819 } 1820 EXPORT_SYMBOL(sock_kzfree_s); 1821 1822 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. 1823 I think, these locks should be removed for datagram sockets. 1824 */ 1825 static long sock_wait_for_wmem(struct sock *sk, long timeo) 1826 { 1827 DEFINE_WAIT(wait); 1828 1829 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk); 1830 for (;;) { 1831 if (!timeo) 1832 break; 1833 if (signal_pending(current)) 1834 break; 1835 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1836 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); 1837 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) 1838 break; 1839 if (sk->sk_shutdown & SEND_SHUTDOWN) 1840 break; 1841 if (sk->sk_err) 1842 break; 1843 timeo = schedule_timeout(timeo); 1844 } 1845 finish_wait(sk_sleep(sk), &wait); 1846 return timeo; 1847 } 1848 1849 1850 /* 1851 * Generic send/receive buffer handlers 1852 */ 1853 1854 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1855 unsigned long data_len, int noblock, 1856 int *errcode, int max_page_order) 1857 { 1858 struct sk_buff *skb; 1859 long timeo; 1860 int err; 1861 1862 timeo = sock_sndtimeo(sk, noblock); 1863 for (;;) { 1864 err = sock_error(sk); 1865 if (err != 0) 1866 goto failure; 1867 1868 err = -EPIPE; 1869 if (sk->sk_shutdown & SEND_SHUTDOWN) 1870 goto failure; 1871 1872 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf) 1873 break; 1874 1875 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); 1876 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 1877 err = -EAGAIN; 1878 if (!timeo) 1879 goto failure; 1880 if (signal_pending(current)) 1881 goto interrupted; 1882 timeo = sock_wait_for_wmem(sk, timeo); 1883 } 1884 skb = alloc_skb_with_frags(header_len, data_len, max_page_order, 1885 errcode, sk->sk_allocation); 1886 if (skb) 1887 skb_set_owner_w(skb, sk); 1888 return skb; 1889 1890 interrupted: 1891 err = sock_intr_errno(timeo); 1892 failure: 1893 *errcode = err; 1894 return NULL; 1895 } 1896 EXPORT_SYMBOL(sock_alloc_send_pskb); 1897 1898 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1899 int noblock, int *errcode) 1900 { 1901 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1902 } 1903 EXPORT_SYMBOL(sock_alloc_send_skb); 1904 1905 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, 1906 struct sockcm_cookie *sockc) 1907 { 1908 u32 tsflags; 1909 1910 switch (cmsg->cmsg_type) { 1911 case SO_MARK: 1912 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) 1913 return -EPERM; 1914 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 1915 return -EINVAL; 1916 sockc->mark = *(u32 *)CMSG_DATA(cmsg); 1917 break; 1918 case SO_TIMESTAMPING: 1919 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32))) 1920 return -EINVAL; 1921 1922 tsflags = *(u32 *)CMSG_DATA(cmsg); 1923 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK) 1924 return -EINVAL; 1925 1926 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK; 1927 sockc->tsflags |= tsflags; 1928 break; 1929 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */ 1930 case SCM_RIGHTS: 1931 case SCM_CREDENTIALS: 1932 break; 1933 default: 1934 return -EINVAL; 1935 } 1936 return 0; 1937 } 1938 EXPORT_SYMBOL(__sock_cmsg_send); 1939 1940 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1941 struct sockcm_cookie *sockc) 1942 { 1943 struct cmsghdr *cmsg; 1944 int ret; 1945 1946 for_each_cmsghdr(cmsg, msg) { 1947 if (!CMSG_OK(msg, cmsg)) 1948 return -EINVAL; 1949 if (cmsg->cmsg_level != SOL_SOCKET) 1950 continue; 1951 ret = __sock_cmsg_send(sk, msg, cmsg, sockc); 1952 if (ret) 1953 return ret; 1954 } 1955 return 0; 1956 } 1957 EXPORT_SYMBOL(sock_cmsg_send); 1958 1959 /* On 32bit arches, an skb frag is limited to 2^15 */ 1960 #define SKB_FRAG_PAGE_ORDER get_order(32768) 1961 1962 /** 1963 * skb_page_frag_refill - check that a page_frag contains enough room 1964 * @sz: minimum size of the fragment we want to get 1965 * @pfrag: pointer to page_frag 1966 * @gfp: priority for memory allocation 1967 * 1968 * Note: While this allocator tries to use high order pages, there is 1969 * no guarantee that allocations succeed. Therefore, @sz MUST be 1970 * less or equal than PAGE_SIZE. 1971 */ 1972 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp) 1973 { 1974 if (pfrag->page) { 1975 if (page_ref_count(pfrag->page) == 1) { 1976 pfrag->offset = 0; 1977 return true; 1978 } 1979 if (pfrag->offset + sz <= pfrag->size) 1980 return true; 1981 put_page(pfrag->page); 1982 } 1983 1984 pfrag->offset = 0; 1985 if (SKB_FRAG_PAGE_ORDER) { 1986 /* Avoid direct reclaim but allow kswapd to wake */ 1987 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) | 1988 __GFP_COMP | __GFP_NOWARN | 1989 __GFP_NORETRY, 1990 SKB_FRAG_PAGE_ORDER); 1991 if (likely(pfrag->page)) { 1992 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER; 1993 return true; 1994 } 1995 } 1996 pfrag->page = alloc_page(gfp); 1997 if (likely(pfrag->page)) { 1998 pfrag->size = PAGE_SIZE; 1999 return true; 2000 } 2001 return false; 2002 } 2003 EXPORT_SYMBOL(skb_page_frag_refill); 2004 2005 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag) 2006 { 2007 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation))) 2008 return true; 2009 2010 sk_enter_memory_pressure(sk); 2011 sk_stream_moderate_sndbuf(sk); 2012 return false; 2013 } 2014 EXPORT_SYMBOL(sk_page_frag_refill); 2015 2016 static void __lock_sock(struct sock *sk) 2017 __releases(&sk->sk_lock.slock) 2018 __acquires(&sk->sk_lock.slock) 2019 { 2020 DEFINE_WAIT(wait); 2021 2022 for (;;) { 2023 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, 2024 TASK_UNINTERRUPTIBLE); 2025 spin_unlock_bh(&sk->sk_lock.slock); 2026 schedule(); 2027 spin_lock_bh(&sk->sk_lock.slock); 2028 if (!sock_owned_by_user(sk)) 2029 break; 2030 } 2031 finish_wait(&sk->sk_lock.wq, &wait); 2032 } 2033 2034 static void __release_sock(struct sock *sk) 2035 __releases(&sk->sk_lock.slock) 2036 __acquires(&sk->sk_lock.slock) 2037 { 2038 struct sk_buff *skb, *next; 2039 2040 while ((skb = sk->sk_backlog.head) != NULL) { 2041 sk->sk_backlog.head = sk->sk_backlog.tail = NULL; 2042 2043 spin_unlock_bh(&sk->sk_lock.slock); 2044 2045 do { 2046 next = skb->next; 2047 prefetch(next); 2048 WARN_ON_ONCE(skb_dst_is_noref(skb)); 2049 skb->next = NULL; 2050 sk_backlog_rcv(sk, skb); 2051 2052 cond_resched(); 2053 2054 skb = next; 2055 } while (skb != NULL); 2056 2057 spin_lock_bh(&sk->sk_lock.slock); 2058 } 2059 2060 /* 2061 * Doing the zeroing here guarantee we can not loop forever 2062 * while a wild producer attempts to flood us. 2063 */ 2064 sk->sk_backlog.len = 0; 2065 } 2066 2067 void __sk_flush_backlog(struct sock *sk) 2068 { 2069 spin_lock_bh(&sk->sk_lock.slock); 2070 __release_sock(sk); 2071 spin_unlock_bh(&sk->sk_lock.slock); 2072 } 2073 2074 /** 2075 * sk_wait_data - wait for data to arrive at sk_receive_queue 2076 * @sk: sock to wait on 2077 * @timeo: for how long 2078 * @skb: last skb seen on sk_receive_queue 2079 * 2080 * Now socket state including sk->sk_err is changed only under lock, 2081 * hence we may omit checks after joining wait queue. 2082 * We check receive queue before schedule() only as optimization; 2083 * it is very likely that release_sock() added new data. 2084 */ 2085 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb) 2086 { 2087 DEFINE_WAIT_FUNC(wait, woken_wake_function); 2088 int rc; 2089 2090 add_wait_queue(sk_sleep(sk), &wait); 2091 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); 2092 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait); 2093 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); 2094 remove_wait_queue(sk_sleep(sk), &wait); 2095 return rc; 2096 } 2097 EXPORT_SYMBOL(sk_wait_data); 2098 2099 /** 2100 * __sk_mem_raise_allocated - increase memory_allocated 2101 * @sk: socket 2102 * @size: memory size to allocate 2103 * @amt: pages to allocate 2104 * @kind: allocation type 2105 * 2106 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc 2107 */ 2108 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind) 2109 { 2110 struct proto *prot = sk->sk_prot; 2111 long allocated = sk_memory_allocated_add(sk, amt); 2112 2113 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 2114 !mem_cgroup_charge_skmem(sk->sk_memcg, amt)) 2115 goto suppress_allocation; 2116 2117 /* Under limit. */ 2118 if (allocated <= sk_prot_mem_limits(sk, 0)) { 2119 sk_leave_memory_pressure(sk); 2120 return 1; 2121 } 2122 2123 /* Under pressure. */ 2124 if (allocated > sk_prot_mem_limits(sk, 1)) 2125 sk_enter_memory_pressure(sk); 2126 2127 /* Over hard limit. */ 2128 if (allocated > sk_prot_mem_limits(sk, 2)) 2129 goto suppress_allocation; 2130 2131 /* guarantee minimum buffer size under pressure */ 2132 if (kind == SK_MEM_RECV) { 2133 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0]) 2134 return 1; 2135 2136 } else { /* SK_MEM_SEND */ 2137 if (sk->sk_type == SOCK_STREAM) { 2138 if (sk->sk_wmem_queued < prot->sysctl_wmem[0]) 2139 return 1; 2140 } else if (atomic_read(&sk->sk_wmem_alloc) < 2141 prot->sysctl_wmem[0]) 2142 return 1; 2143 } 2144 2145 if (sk_has_memory_pressure(sk)) { 2146 int alloc; 2147 2148 if (!sk_under_memory_pressure(sk)) 2149 return 1; 2150 alloc = sk_sockets_allocated_read_positive(sk); 2151 if (sk_prot_mem_limits(sk, 2) > alloc * 2152 sk_mem_pages(sk->sk_wmem_queued + 2153 atomic_read(&sk->sk_rmem_alloc) + 2154 sk->sk_forward_alloc)) 2155 return 1; 2156 } 2157 2158 suppress_allocation: 2159 2160 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) { 2161 sk_stream_moderate_sndbuf(sk); 2162 2163 /* Fail only if socket is _under_ its sndbuf. 2164 * In this case we cannot block, so that we have to fail. 2165 */ 2166 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) 2167 return 1; 2168 } 2169 2170 trace_sock_exceed_buf_limit(sk, prot, allocated); 2171 2172 sk_memory_allocated_sub(sk, amt); 2173 2174 if (mem_cgroup_sockets_enabled && sk->sk_memcg) 2175 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt); 2176 2177 return 0; 2178 } 2179 EXPORT_SYMBOL(__sk_mem_raise_allocated); 2180 2181 /** 2182 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated 2183 * @sk: socket 2184 * @size: memory size to allocate 2185 * @kind: allocation type 2186 * 2187 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means 2188 * rmem allocation. This function assumes that protocols which have 2189 * memory_pressure use sk_wmem_queued as write buffer accounting. 2190 */ 2191 int __sk_mem_schedule(struct sock *sk, int size, int kind) 2192 { 2193 int ret, amt = sk_mem_pages(size); 2194 2195 sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT; 2196 ret = __sk_mem_raise_allocated(sk, size, amt, kind); 2197 if (!ret) 2198 sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT; 2199 return ret; 2200 } 2201 EXPORT_SYMBOL(__sk_mem_schedule); 2202 2203 /** 2204 * __sk_mem_reduce_allocated - reclaim memory_allocated 2205 * @sk: socket 2206 * @amount: number of quanta 2207 * 2208 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc 2209 */ 2210 void __sk_mem_reduce_allocated(struct sock *sk, int amount) 2211 { 2212 sk_memory_allocated_sub(sk, amount); 2213 2214 if (mem_cgroup_sockets_enabled && sk->sk_memcg) 2215 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount); 2216 2217 if (sk_under_memory_pressure(sk) && 2218 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0))) 2219 sk_leave_memory_pressure(sk); 2220 } 2221 EXPORT_SYMBOL(__sk_mem_reduce_allocated); 2222 2223 /** 2224 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated 2225 * @sk: socket 2226 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple) 2227 */ 2228 void __sk_mem_reclaim(struct sock *sk, int amount) 2229 { 2230 amount >>= SK_MEM_QUANTUM_SHIFT; 2231 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT; 2232 __sk_mem_reduce_allocated(sk, amount); 2233 } 2234 EXPORT_SYMBOL(__sk_mem_reclaim); 2235 2236 int sk_set_peek_off(struct sock *sk, int val) 2237 { 2238 if (val < 0) 2239 return -EINVAL; 2240 2241 sk->sk_peek_off = val; 2242 return 0; 2243 } 2244 EXPORT_SYMBOL_GPL(sk_set_peek_off); 2245 2246 /* 2247 * Set of default routines for initialising struct proto_ops when 2248 * the protocol does not support a particular function. In certain 2249 * cases where it makes no sense for a protocol to have a "do nothing" 2250 * function, some default processing is provided. 2251 */ 2252 2253 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) 2254 { 2255 return -EOPNOTSUPP; 2256 } 2257 EXPORT_SYMBOL(sock_no_bind); 2258 2259 int sock_no_connect(struct socket *sock, struct sockaddr *saddr, 2260 int len, int flags) 2261 { 2262 return -EOPNOTSUPP; 2263 } 2264 EXPORT_SYMBOL(sock_no_connect); 2265 2266 int sock_no_socketpair(struct socket *sock1, struct socket *sock2) 2267 { 2268 return -EOPNOTSUPP; 2269 } 2270 EXPORT_SYMBOL(sock_no_socketpair); 2271 2272 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) 2273 { 2274 return -EOPNOTSUPP; 2275 } 2276 EXPORT_SYMBOL(sock_no_accept); 2277 2278 int sock_no_getname(struct socket *sock, struct sockaddr *saddr, 2279 int *len, int peer) 2280 { 2281 return -EOPNOTSUPP; 2282 } 2283 EXPORT_SYMBOL(sock_no_getname); 2284 2285 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt) 2286 { 2287 return 0; 2288 } 2289 EXPORT_SYMBOL(sock_no_poll); 2290 2291 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) 2292 { 2293 return -EOPNOTSUPP; 2294 } 2295 EXPORT_SYMBOL(sock_no_ioctl); 2296 2297 int sock_no_listen(struct socket *sock, int backlog) 2298 { 2299 return -EOPNOTSUPP; 2300 } 2301 EXPORT_SYMBOL(sock_no_listen); 2302 2303 int sock_no_shutdown(struct socket *sock, int how) 2304 { 2305 return -EOPNOTSUPP; 2306 } 2307 EXPORT_SYMBOL(sock_no_shutdown); 2308 2309 int sock_no_setsockopt(struct socket *sock, int level, int optname, 2310 char __user *optval, unsigned int optlen) 2311 { 2312 return -EOPNOTSUPP; 2313 } 2314 EXPORT_SYMBOL(sock_no_setsockopt); 2315 2316 int sock_no_getsockopt(struct socket *sock, int level, int optname, 2317 char __user *optval, int __user *optlen) 2318 { 2319 return -EOPNOTSUPP; 2320 } 2321 EXPORT_SYMBOL(sock_no_getsockopt); 2322 2323 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len) 2324 { 2325 return -EOPNOTSUPP; 2326 } 2327 EXPORT_SYMBOL(sock_no_sendmsg); 2328 2329 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len, 2330 int flags) 2331 { 2332 return -EOPNOTSUPP; 2333 } 2334 EXPORT_SYMBOL(sock_no_recvmsg); 2335 2336 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) 2337 { 2338 /* Mirror missing mmap method error code */ 2339 return -ENODEV; 2340 } 2341 EXPORT_SYMBOL(sock_no_mmap); 2342 2343 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) 2344 { 2345 ssize_t res; 2346 struct msghdr msg = {.msg_flags = flags}; 2347 struct kvec iov; 2348 char *kaddr = kmap(page); 2349 iov.iov_base = kaddr + offset; 2350 iov.iov_len = size; 2351 res = kernel_sendmsg(sock, &msg, &iov, 1, size); 2352 kunmap(page); 2353 return res; 2354 } 2355 EXPORT_SYMBOL(sock_no_sendpage); 2356 2357 /* 2358 * Default Socket Callbacks 2359 */ 2360 2361 static void sock_def_wakeup(struct sock *sk) 2362 { 2363 struct socket_wq *wq; 2364 2365 rcu_read_lock(); 2366 wq = rcu_dereference(sk->sk_wq); 2367 if (skwq_has_sleeper(wq)) 2368 wake_up_interruptible_all(&wq->wait); 2369 rcu_read_unlock(); 2370 } 2371 2372 static void sock_def_error_report(struct sock *sk) 2373 { 2374 struct socket_wq *wq; 2375 2376 rcu_read_lock(); 2377 wq = rcu_dereference(sk->sk_wq); 2378 if (skwq_has_sleeper(wq)) 2379 wake_up_interruptible_poll(&wq->wait, POLLERR); 2380 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR); 2381 rcu_read_unlock(); 2382 } 2383 2384 static void sock_def_readable(struct sock *sk) 2385 { 2386 struct socket_wq *wq; 2387 2388 rcu_read_lock(); 2389 wq = rcu_dereference(sk->sk_wq); 2390 if (skwq_has_sleeper(wq)) 2391 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI | 2392 POLLRDNORM | POLLRDBAND); 2393 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); 2394 rcu_read_unlock(); 2395 } 2396 2397 static void sock_def_write_space(struct sock *sk) 2398 { 2399 struct socket_wq *wq; 2400 2401 rcu_read_lock(); 2402 2403 /* Do not wake up a writer until he can make "significant" 2404 * progress. --DaveM 2405 */ 2406 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { 2407 wq = rcu_dereference(sk->sk_wq); 2408 if (skwq_has_sleeper(wq)) 2409 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT | 2410 POLLWRNORM | POLLWRBAND); 2411 2412 /* Should agree with poll, otherwise some programs break */ 2413 if (sock_writeable(sk)) 2414 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT); 2415 } 2416 2417 rcu_read_unlock(); 2418 } 2419 2420 static void sock_def_destruct(struct sock *sk) 2421 { 2422 } 2423 2424 void sk_send_sigurg(struct sock *sk) 2425 { 2426 if (sk->sk_socket && sk->sk_socket->file) 2427 if (send_sigurg(&sk->sk_socket->file->f_owner)) 2428 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI); 2429 } 2430 EXPORT_SYMBOL(sk_send_sigurg); 2431 2432 void sk_reset_timer(struct sock *sk, struct timer_list* timer, 2433 unsigned long expires) 2434 { 2435 if (!mod_timer(timer, expires)) 2436 sock_hold(sk); 2437 } 2438 EXPORT_SYMBOL(sk_reset_timer); 2439 2440 void sk_stop_timer(struct sock *sk, struct timer_list* timer) 2441 { 2442 if (del_timer(timer)) 2443 __sock_put(sk); 2444 } 2445 EXPORT_SYMBOL(sk_stop_timer); 2446 2447 void sock_init_data(struct socket *sock, struct sock *sk) 2448 { 2449 skb_queue_head_init(&sk->sk_receive_queue); 2450 skb_queue_head_init(&sk->sk_write_queue); 2451 skb_queue_head_init(&sk->sk_error_queue); 2452 2453 sk->sk_send_head = NULL; 2454 2455 init_timer(&sk->sk_timer); 2456 2457 sk->sk_allocation = GFP_KERNEL; 2458 sk->sk_rcvbuf = sysctl_rmem_default; 2459 sk->sk_sndbuf = sysctl_wmem_default; 2460 sk->sk_state = TCP_CLOSE; 2461 sk_set_socket(sk, sock); 2462 2463 sock_set_flag(sk, SOCK_ZAPPED); 2464 2465 if (sock) { 2466 sk->sk_type = sock->type; 2467 sk->sk_wq = sock->wq; 2468 sock->sk = sk; 2469 sk->sk_uid = SOCK_INODE(sock)->i_uid; 2470 } else { 2471 sk->sk_wq = NULL; 2472 sk->sk_uid = make_kuid(sock_net(sk)->user_ns, 0); 2473 } 2474 2475 rwlock_init(&sk->sk_callback_lock); 2476 lockdep_set_class_and_name(&sk->sk_callback_lock, 2477 af_callback_keys + sk->sk_family, 2478 af_family_clock_key_strings[sk->sk_family]); 2479 2480 sk->sk_state_change = sock_def_wakeup; 2481 sk->sk_data_ready = sock_def_readable; 2482 sk->sk_write_space = sock_def_write_space; 2483 sk->sk_error_report = sock_def_error_report; 2484 sk->sk_destruct = sock_def_destruct; 2485 2486 sk->sk_frag.page = NULL; 2487 sk->sk_frag.offset = 0; 2488 sk->sk_peek_off = -1; 2489 2490 sk->sk_peer_pid = NULL; 2491 sk->sk_peer_cred = NULL; 2492 sk->sk_write_pending = 0; 2493 sk->sk_rcvlowat = 1; 2494 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; 2495 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; 2496 2497 sk->sk_stamp = ktime_set(-1L, 0); 2498 2499 #ifdef CONFIG_NET_RX_BUSY_POLL 2500 sk->sk_napi_id = 0; 2501 sk->sk_ll_usec = sysctl_net_busy_read; 2502 #endif 2503 2504 sk->sk_max_pacing_rate = ~0U; 2505 sk->sk_pacing_rate = ~0U; 2506 sk->sk_incoming_cpu = -1; 2507 /* 2508 * Before updating sk_refcnt, we must commit prior changes to memory 2509 * (Documentation/RCU/rculist_nulls.txt for details) 2510 */ 2511 smp_wmb(); 2512 atomic_set(&sk->sk_refcnt, 1); 2513 atomic_set(&sk->sk_drops, 0); 2514 } 2515 EXPORT_SYMBOL(sock_init_data); 2516 2517 void lock_sock_nested(struct sock *sk, int subclass) 2518 { 2519 might_sleep(); 2520 spin_lock_bh(&sk->sk_lock.slock); 2521 if (sk->sk_lock.owned) 2522 __lock_sock(sk); 2523 sk->sk_lock.owned = 1; 2524 spin_unlock(&sk->sk_lock.slock); 2525 /* 2526 * The sk_lock has mutex_lock() semantics here: 2527 */ 2528 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); 2529 local_bh_enable(); 2530 } 2531 EXPORT_SYMBOL(lock_sock_nested); 2532 2533 void release_sock(struct sock *sk) 2534 { 2535 spin_lock_bh(&sk->sk_lock.slock); 2536 if (sk->sk_backlog.tail) 2537 __release_sock(sk); 2538 2539 /* Warning : release_cb() might need to release sk ownership, 2540 * ie call sock_release_ownership(sk) before us. 2541 */ 2542 if (sk->sk_prot->release_cb) 2543 sk->sk_prot->release_cb(sk); 2544 2545 sock_release_ownership(sk); 2546 if (waitqueue_active(&sk->sk_lock.wq)) 2547 wake_up(&sk->sk_lock.wq); 2548 spin_unlock_bh(&sk->sk_lock.slock); 2549 } 2550 EXPORT_SYMBOL(release_sock); 2551 2552 /** 2553 * lock_sock_fast - fast version of lock_sock 2554 * @sk: socket 2555 * 2556 * This version should be used for very small section, where process wont block 2557 * return false if fast path is taken 2558 * sk_lock.slock locked, owned = 0, BH disabled 2559 * return true if slow path is taken 2560 * sk_lock.slock unlocked, owned = 1, BH enabled 2561 */ 2562 bool lock_sock_fast(struct sock *sk) 2563 { 2564 might_sleep(); 2565 spin_lock_bh(&sk->sk_lock.slock); 2566 2567 if (!sk->sk_lock.owned) 2568 /* 2569 * Note : We must disable BH 2570 */ 2571 return false; 2572 2573 __lock_sock(sk); 2574 sk->sk_lock.owned = 1; 2575 spin_unlock(&sk->sk_lock.slock); 2576 /* 2577 * The sk_lock has mutex_lock() semantics here: 2578 */ 2579 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 2580 local_bh_enable(); 2581 return true; 2582 } 2583 EXPORT_SYMBOL(lock_sock_fast); 2584 2585 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) 2586 { 2587 struct timeval tv; 2588 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2589 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2590 tv = ktime_to_timeval(sk->sk_stamp); 2591 if (tv.tv_sec == -1) 2592 return -ENOENT; 2593 if (tv.tv_sec == 0) { 2594 sk->sk_stamp = ktime_get_real(); 2595 tv = ktime_to_timeval(sk->sk_stamp); 2596 } 2597 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0; 2598 } 2599 EXPORT_SYMBOL(sock_get_timestamp); 2600 2601 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp) 2602 { 2603 struct timespec ts; 2604 if (!sock_flag(sk, SOCK_TIMESTAMP)) 2605 sock_enable_timestamp(sk, SOCK_TIMESTAMP); 2606 ts = ktime_to_timespec(sk->sk_stamp); 2607 if (ts.tv_sec == -1) 2608 return -ENOENT; 2609 if (ts.tv_sec == 0) { 2610 sk->sk_stamp = ktime_get_real(); 2611 ts = ktime_to_timespec(sk->sk_stamp); 2612 } 2613 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0; 2614 } 2615 EXPORT_SYMBOL(sock_get_timestampns); 2616 2617 void sock_enable_timestamp(struct sock *sk, int flag) 2618 { 2619 if (!sock_flag(sk, flag)) { 2620 unsigned long previous_flags = sk->sk_flags; 2621 2622 sock_set_flag(sk, flag); 2623 /* 2624 * we just set one of the two flags which require net 2625 * time stamping, but time stamping might have been on 2626 * already because of the other one 2627 */ 2628 if (sock_needs_netstamp(sk) && 2629 !(previous_flags & SK_FLAGS_TIMESTAMP)) 2630 net_enable_timestamp(); 2631 } 2632 } 2633 2634 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, 2635 int level, int type) 2636 { 2637 struct sock_exterr_skb *serr; 2638 struct sk_buff *skb; 2639 int copied, err; 2640 2641 err = -EAGAIN; 2642 skb = sock_dequeue_err_skb(sk); 2643 if (skb == NULL) 2644 goto out; 2645 2646 copied = skb->len; 2647 if (copied > len) { 2648 msg->msg_flags |= MSG_TRUNC; 2649 copied = len; 2650 } 2651 err = skb_copy_datagram_msg(skb, 0, msg, copied); 2652 if (err) 2653 goto out_free_skb; 2654 2655 sock_recv_timestamp(msg, sk, skb); 2656 2657 serr = SKB_EXT_ERR(skb); 2658 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee); 2659 2660 msg->msg_flags |= MSG_ERRQUEUE; 2661 err = copied; 2662 2663 out_free_skb: 2664 kfree_skb(skb); 2665 out: 2666 return err; 2667 } 2668 EXPORT_SYMBOL(sock_recv_errqueue); 2669 2670 /* 2671 * Get a socket option on an socket. 2672 * 2673 * FIX: POSIX 1003.1g is very ambiguous here. It states that 2674 * asynchronous errors should be reported by getsockopt. We assume 2675 * this means if you specify SO_ERROR (otherwise whats the point of it). 2676 */ 2677 int sock_common_getsockopt(struct socket *sock, int level, int optname, 2678 char __user *optval, int __user *optlen) 2679 { 2680 struct sock *sk = sock->sk; 2681 2682 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2683 } 2684 EXPORT_SYMBOL(sock_common_getsockopt); 2685 2686 #ifdef CONFIG_COMPAT 2687 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname, 2688 char __user *optval, int __user *optlen) 2689 { 2690 struct sock *sk = sock->sk; 2691 2692 if (sk->sk_prot->compat_getsockopt != NULL) 2693 return sk->sk_prot->compat_getsockopt(sk, level, optname, 2694 optval, optlen); 2695 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); 2696 } 2697 EXPORT_SYMBOL(compat_sock_common_getsockopt); 2698 #endif 2699 2700 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 2701 int flags) 2702 { 2703 struct sock *sk = sock->sk; 2704 int addr_len = 0; 2705 int err; 2706 2707 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, 2708 flags & ~MSG_DONTWAIT, &addr_len); 2709 if (err >= 0) 2710 msg->msg_namelen = addr_len; 2711 return err; 2712 } 2713 EXPORT_SYMBOL(sock_common_recvmsg); 2714 2715 /* 2716 * Set socket options on an inet socket. 2717 */ 2718 int sock_common_setsockopt(struct socket *sock, int level, int optname, 2719 char __user *optval, unsigned int optlen) 2720 { 2721 struct sock *sk = sock->sk; 2722 2723 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2724 } 2725 EXPORT_SYMBOL(sock_common_setsockopt); 2726 2727 #ifdef CONFIG_COMPAT 2728 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname, 2729 char __user *optval, unsigned int optlen) 2730 { 2731 struct sock *sk = sock->sk; 2732 2733 if (sk->sk_prot->compat_setsockopt != NULL) 2734 return sk->sk_prot->compat_setsockopt(sk, level, optname, 2735 optval, optlen); 2736 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); 2737 } 2738 EXPORT_SYMBOL(compat_sock_common_setsockopt); 2739 #endif 2740 2741 void sk_common_release(struct sock *sk) 2742 { 2743 if (sk->sk_prot->destroy) 2744 sk->sk_prot->destroy(sk); 2745 2746 /* 2747 * Observation: when sock_common_release is called, processes have 2748 * no access to socket. But net still has. 2749 * Step one, detach it from networking: 2750 * 2751 * A. Remove from hash tables. 2752 */ 2753 2754 sk->sk_prot->unhash(sk); 2755 2756 /* 2757 * In this point socket cannot receive new packets, but it is possible 2758 * that some packets are in flight because some CPU runs receiver and 2759 * did hash table lookup before we unhashed socket. They will achieve 2760 * receive queue and will be purged by socket destructor. 2761 * 2762 * Also we still have packets pending on receive queue and probably, 2763 * our own packets waiting in device queues. sock_destroy will drain 2764 * receive queue, but transmitted packets will delay socket destruction 2765 * until the last reference will be released. 2766 */ 2767 2768 sock_orphan(sk); 2769 2770 xfrm_sk_free_policy(sk); 2771 2772 sk_refcnt_debug_release(sk); 2773 2774 if (sk->sk_frag.page) { 2775 put_page(sk->sk_frag.page); 2776 sk->sk_frag.page = NULL; 2777 } 2778 2779 sock_put(sk); 2780 } 2781 EXPORT_SYMBOL(sk_common_release); 2782 2783 #ifdef CONFIG_PROC_FS 2784 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 2785 struct prot_inuse { 2786 int val[PROTO_INUSE_NR]; 2787 }; 2788 2789 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR); 2790 2791 #ifdef CONFIG_NET_NS 2792 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2793 { 2794 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val); 2795 } 2796 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2797 2798 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2799 { 2800 int cpu, idx = prot->inuse_idx; 2801 int res = 0; 2802 2803 for_each_possible_cpu(cpu) 2804 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx]; 2805 2806 return res >= 0 ? res : 0; 2807 } 2808 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2809 2810 static int __net_init sock_inuse_init_net(struct net *net) 2811 { 2812 net->core.inuse = alloc_percpu(struct prot_inuse); 2813 return net->core.inuse ? 0 : -ENOMEM; 2814 } 2815 2816 static void __net_exit sock_inuse_exit_net(struct net *net) 2817 { 2818 free_percpu(net->core.inuse); 2819 } 2820 2821 static struct pernet_operations net_inuse_ops = { 2822 .init = sock_inuse_init_net, 2823 .exit = sock_inuse_exit_net, 2824 }; 2825 2826 static __init int net_inuse_init(void) 2827 { 2828 if (register_pernet_subsys(&net_inuse_ops)) 2829 panic("Cannot initialize net inuse counters"); 2830 2831 return 0; 2832 } 2833 2834 core_initcall(net_inuse_init); 2835 #else 2836 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse); 2837 2838 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val) 2839 { 2840 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val); 2841 } 2842 EXPORT_SYMBOL_GPL(sock_prot_inuse_add); 2843 2844 int sock_prot_inuse_get(struct net *net, struct proto *prot) 2845 { 2846 int cpu, idx = prot->inuse_idx; 2847 int res = 0; 2848 2849 for_each_possible_cpu(cpu) 2850 res += per_cpu(prot_inuse, cpu).val[idx]; 2851 2852 return res >= 0 ? res : 0; 2853 } 2854 EXPORT_SYMBOL_GPL(sock_prot_inuse_get); 2855 #endif 2856 2857 static void assign_proto_idx(struct proto *prot) 2858 { 2859 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR); 2860 2861 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) { 2862 pr_err("PROTO_INUSE_NR exhausted\n"); 2863 return; 2864 } 2865 2866 set_bit(prot->inuse_idx, proto_inuse_idx); 2867 } 2868 2869 static void release_proto_idx(struct proto *prot) 2870 { 2871 if (prot->inuse_idx != PROTO_INUSE_NR - 1) 2872 clear_bit(prot->inuse_idx, proto_inuse_idx); 2873 } 2874 #else 2875 static inline void assign_proto_idx(struct proto *prot) 2876 { 2877 } 2878 2879 static inline void release_proto_idx(struct proto *prot) 2880 { 2881 } 2882 #endif 2883 2884 static void req_prot_cleanup(struct request_sock_ops *rsk_prot) 2885 { 2886 if (!rsk_prot) 2887 return; 2888 kfree(rsk_prot->slab_name); 2889 rsk_prot->slab_name = NULL; 2890 kmem_cache_destroy(rsk_prot->slab); 2891 rsk_prot->slab = NULL; 2892 } 2893 2894 static int req_prot_init(const struct proto *prot) 2895 { 2896 struct request_sock_ops *rsk_prot = prot->rsk_prot; 2897 2898 if (!rsk_prot) 2899 return 0; 2900 2901 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", 2902 prot->name); 2903 if (!rsk_prot->slab_name) 2904 return -ENOMEM; 2905 2906 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name, 2907 rsk_prot->obj_size, 0, 2908 prot->slab_flags, NULL); 2909 2910 if (!rsk_prot->slab) { 2911 pr_crit("%s: Can't create request sock SLAB cache!\n", 2912 prot->name); 2913 return -ENOMEM; 2914 } 2915 return 0; 2916 } 2917 2918 int proto_register(struct proto *prot, int alloc_slab) 2919 { 2920 if (alloc_slab) { 2921 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, 2922 SLAB_HWCACHE_ALIGN | prot->slab_flags, 2923 NULL); 2924 2925 if (prot->slab == NULL) { 2926 pr_crit("%s: Can't create sock SLAB cache!\n", 2927 prot->name); 2928 goto out; 2929 } 2930 2931 if (req_prot_init(prot)) 2932 goto out_free_request_sock_slab; 2933 2934 if (prot->twsk_prot != NULL) { 2935 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name); 2936 2937 if (prot->twsk_prot->twsk_slab_name == NULL) 2938 goto out_free_request_sock_slab; 2939 2940 prot->twsk_prot->twsk_slab = 2941 kmem_cache_create(prot->twsk_prot->twsk_slab_name, 2942 prot->twsk_prot->twsk_obj_size, 2943 0, 2944 prot->slab_flags, 2945 NULL); 2946 if (prot->twsk_prot->twsk_slab == NULL) 2947 goto out_free_timewait_sock_slab_name; 2948 } 2949 } 2950 2951 mutex_lock(&proto_list_mutex); 2952 list_add(&prot->node, &proto_list); 2953 assign_proto_idx(prot); 2954 mutex_unlock(&proto_list_mutex); 2955 return 0; 2956 2957 out_free_timewait_sock_slab_name: 2958 kfree(prot->twsk_prot->twsk_slab_name); 2959 out_free_request_sock_slab: 2960 req_prot_cleanup(prot->rsk_prot); 2961 2962 kmem_cache_destroy(prot->slab); 2963 prot->slab = NULL; 2964 out: 2965 return -ENOBUFS; 2966 } 2967 EXPORT_SYMBOL(proto_register); 2968 2969 void proto_unregister(struct proto *prot) 2970 { 2971 mutex_lock(&proto_list_mutex); 2972 release_proto_idx(prot); 2973 list_del(&prot->node); 2974 mutex_unlock(&proto_list_mutex); 2975 2976 kmem_cache_destroy(prot->slab); 2977 prot->slab = NULL; 2978 2979 req_prot_cleanup(prot->rsk_prot); 2980 2981 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) { 2982 kmem_cache_destroy(prot->twsk_prot->twsk_slab); 2983 kfree(prot->twsk_prot->twsk_slab_name); 2984 prot->twsk_prot->twsk_slab = NULL; 2985 } 2986 } 2987 EXPORT_SYMBOL(proto_unregister); 2988 2989 #ifdef CONFIG_PROC_FS 2990 static void *proto_seq_start(struct seq_file *seq, loff_t *pos) 2991 __acquires(proto_list_mutex) 2992 { 2993 mutex_lock(&proto_list_mutex); 2994 return seq_list_start_head(&proto_list, *pos); 2995 } 2996 2997 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) 2998 { 2999 return seq_list_next(v, &proto_list, pos); 3000 } 3001 3002 static void proto_seq_stop(struct seq_file *seq, void *v) 3003 __releases(proto_list_mutex) 3004 { 3005 mutex_unlock(&proto_list_mutex); 3006 } 3007 3008 static char proto_method_implemented(const void *method) 3009 { 3010 return method == NULL ? 'n' : 'y'; 3011 } 3012 static long sock_prot_memory_allocated(struct proto *proto) 3013 { 3014 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L; 3015 } 3016 3017 static char *sock_prot_memory_pressure(struct proto *proto) 3018 { 3019 return proto->memory_pressure != NULL ? 3020 proto_memory_pressure(proto) ? "yes" : "no" : "NI"; 3021 } 3022 3023 static void proto_seq_printf(struct seq_file *seq, struct proto *proto) 3024 { 3025 3026 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s " 3027 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", 3028 proto->name, 3029 proto->obj_size, 3030 sock_prot_inuse_get(seq_file_net(seq), proto), 3031 sock_prot_memory_allocated(proto), 3032 sock_prot_memory_pressure(proto), 3033 proto->max_header, 3034 proto->slab == NULL ? "no" : "yes", 3035 module_name(proto->owner), 3036 proto_method_implemented(proto->close), 3037 proto_method_implemented(proto->connect), 3038 proto_method_implemented(proto->disconnect), 3039 proto_method_implemented(proto->accept), 3040 proto_method_implemented(proto->ioctl), 3041 proto_method_implemented(proto->init), 3042 proto_method_implemented(proto->destroy), 3043 proto_method_implemented(proto->shutdown), 3044 proto_method_implemented(proto->setsockopt), 3045 proto_method_implemented(proto->getsockopt), 3046 proto_method_implemented(proto->sendmsg), 3047 proto_method_implemented(proto->recvmsg), 3048 proto_method_implemented(proto->sendpage), 3049 proto_method_implemented(proto->bind), 3050 proto_method_implemented(proto->backlog_rcv), 3051 proto_method_implemented(proto->hash), 3052 proto_method_implemented(proto->unhash), 3053 proto_method_implemented(proto->get_port), 3054 proto_method_implemented(proto->enter_memory_pressure)); 3055 } 3056 3057 static int proto_seq_show(struct seq_file *seq, void *v) 3058 { 3059 if (v == &proto_list) 3060 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", 3061 "protocol", 3062 "size", 3063 "sockets", 3064 "memory", 3065 "press", 3066 "maxhdr", 3067 "slab", 3068 "module", 3069 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); 3070 else 3071 proto_seq_printf(seq, list_entry(v, struct proto, node)); 3072 return 0; 3073 } 3074 3075 static const struct seq_operations proto_seq_ops = { 3076 .start = proto_seq_start, 3077 .next = proto_seq_next, 3078 .stop = proto_seq_stop, 3079 .show = proto_seq_show, 3080 }; 3081 3082 static int proto_seq_open(struct inode *inode, struct file *file) 3083 { 3084 return seq_open_net(inode, file, &proto_seq_ops, 3085 sizeof(struct seq_net_private)); 3086 } 3087 3088 static const struct file_operations proto_seq_fops = { 3089 .owner = THIS_MODULE, 3090 .open = proto_seq_open, 3091 .read = seq_read, 3092 .llseek = seq_lseek, 3093 .release = seq_release_net, 3094 }; 3095 3096 static __net_init int proto_init_net(struct net *net) 3097 { 3098 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops)) 3099 return -ENOMEM; 3100 3101 return 0; 3102 } 3103 3104 static __net_exit void proto_exit_net(struct net *net) 3105 { 3106 remove_proc_entry("protocols", net->proc_net); 3107 } 3108 3109 3110 static __net_initdata struct pernet_operations proto_net_ops = { 3111 .init = proto_init_net, 3112 .exit = proto_exit_net, 3113 }; 3114 3115 static int __init proto_init(void) 3116 { 3117 return register_pernet_subsys(&proto_net_ops); 3118 } 3119 3120 subsys_initcall(proto_init); 3121 3122 #endif /* PROC_FS */ 3123