1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * INET An implementation of the TCP/IP protocol suite for the LINUX 4 * operating system. INET is implemented using the BSD Socket 5 * interface as the means of communication with the user level. 6 * 7 * Definitions for the AF_INET socket handler. 8 * 9 * Version: @(#)sock.h 1.0.4 05/13/93 10 * 11 * Authors: Ross Biro 12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 13 * Corey Minyard <wf-rch!minyard@relay.EU.net> 14 * Florian La Roche <flla@stud.uni-sb.de> 15 * 16 * Fixes: 17 * Alan Cox : Volatiles in skbuff pointers. See 18 * skbuff comments. May be overdone, 19 * better to prove they can be removed 20 * than the reverse. 21 * Alan Cox : Added a zapped field for tcp to note 22 * a socket is reset and must stay shut up 23 * Alan Cox : New fields for options 24 * Pauline Middelink : identd support 25 * Alan Cox : Eliminate low level recv/recvfrom 26 * David S. Miller : New socket lookup architecture. 27 * Steve Whitehouse: Default routines for sock_ops 28 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made 29 * protinfo be just a void pointer, as the 30 * protocol specific parts were moved to 31 * respective headers and ipv4/v6, etc now 32 * use private slabcaches for its socks 33 * Pedro Hortas : New flags field for socket options 34 */ 35 #ifndef _SOCK_H 36 #define _SOCK_H 37 38 #include <linux/hardirq.h> 39 #include <linux/kernel.h> 40 #include <linux/list.h> 41 #include <linux/list_nulls.h> 42 #include <linux/timer.h> 43 #include <linux/cache.h> 44 #include <linux/bitops.h> 45 #include <linux/lockdep.h> 46 #include <linux/netdevice.h> 47 #include <linux/skbuff.h> /* struct sk_buff */ 48 #include <linux/mm.h> 49 #include <linux/security.h> 50 #include <linux/slab.h> 51 #include <linux/uaccess.h> 52 #include <linux/page_counter.h> 53 #include <linux/memcontrol.h> 54 #include <linux/static_key.h> 55 #include <linux/sched.h> 56 #include <linux/wait.h> 57 #include <linux/cgroup-defs.h> 58 #include <linux/rbtree.h> 59 #include <linux/filter.h> 60 #include <linux/rculist_nulls.h> 61 #include <linux/poll.h> 62 #include <linux/sockptr.h> 63 #include <linux/indirect_call_wrapper.h> 64 #include <linux/atomic.h> 65 #include <linux/refcount.h> 66 #include <net/dst.h> 67 #include <net/checksum.h> 68 #include <net/tcp_states.h> 69 #include <linux/net_tstamp.h> 70 #include <net/l3mdev.h> 71 72 /* 73 * This structure really needs to be cleaned up. 74 * Most of it is for TCP, and not used by any of 75 * the other protocols. 76 */ 77 78 /* Define this to get the SOCK_DBG debugging facility. */ 79 #define SOCK_DEBUGGING 80 #ifdef SOCK_DEBUGGING 81 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \ 82 printk(KERN_DEBUG msg); } while (0) 83 #else 84 /* Validate arguments and do nothing */ 85 static inline __printf(2, 3) 86 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...) 87 { 88 } 89 #endif 90 91 /* This is the per-socket lock. The spinlock provides a synchronization 92 * between user contexts and software interrupt processing, whereas the 93 * mini-semaphore synchronizes multiple users amongst themselves. 94 */ 95 typedef struct { 96 spinlock_t slock; 97 int owned; 98 wait_queue_head_t wq; 99 /* 100 * We express the mutex-alike socket_lock semantics 101 * to the lock validator by explicitly managing 102 * the slock as a lock variant (in addition to 103 * the slock itself): 104 */ 105 #ifdef CONFIG_DEBUG_LOCK_ALLOC 106 struct lockdep_map dep_map; 107 #endif 108 } socket_lock_t; 109 110 struct sock; 111 struct proto; 112 struct net; 113 114 typedef __u32 __bitwise __portpair; 115 typedef __u64 __bitwise __addrpair; 116 117 /** 118 * struct sock_common - minimal network layer representation of sockets 119 * @skc_daddr: Foreign IPv4 addr 120 * @skc_rcv_saddr: Bound local IPv4 addr 121 * @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr 122 * @skc_hash: hash value used with various protocol lookup tables 123 * @skc_u16hashes: two u16 hash values used by UDP lookup tables 124 * @skc_dport: placeholder for inet_dport/tw_dport 125 * @skc_num: placeholder for inet_num/tw_num 126 * @skc_portpair: __u32 union of @skc_dport & @skc_num 127 * @skc_family: network address family 128 * @skc_state: Connection state 129 * @skc_reuse: %SO_REUSEADDR setting 130 * @skc_reuseport: %SO_REUSEPORT setting 131 * @skc_ipv6only: socket is IPV6 only 132 * @skc_net_refcnt: socket is using net ref counting 133 * @skc_bound_dev_if: bound device index if != 0 134 * @skc_bind_node: bind hash linkage for various protocol lookup tables 135 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol 136 * @skc_prot: protocol handlers inside a network family 137 * @skc_net: reference to the network namespace of this socket 138 * @skc_v6_daddr: IPV6 destination address 139 * @skc_v6_rcv_saddr: IPV6 source address 140 * @skc_cookie: socket's cookie value 141 * @skc_node: main hash linkage for various protocol lookup tables 142 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol 143 * @skc_tx_queue_mapping: tx queue number for this connection 144 * @skc_rx_queue_mapping: rx queue number for this connection 145 * @skc_flags: place holder for sk_flags 146 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, 147 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings 148 * @skc_listener: connection request listener socket (aka rsk_listener) 149 * [union with @skc_flags] 150 * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row 151 * [union with @skc_flags] 152 * @skc_incoming_cpu: record/match cpu processing incoming packets 153 * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled) 154 * [union with @skc_incoming_cpu] 155 * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number 156 * [union with @skc_incoming_cpu] 157 * @skc_refcnt: reference count 158 * 159 * This is the minimal network layer representation of sockets, the header 160 * for struct sock and struct inet_timewait_sock. 161 */ 162 struct sock_common { 163 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned 164 * address on 64bit arches : cf INET_MATCH() 165 */ 166 union { 167 __addrpair skc_addrpair; 168 struct { 169 __be32 skc_daddr; 170 __be32 skc_rcv_saddr; 171 }; 172 }; 173 union { 174 unsigned int skc_hash; 175 __u16 skc_u16hashes[2]; 176 }; 177 /* skc_dport && skc_num must be grouped as well */ 178 union { 179 __portpair skc_portpair; 180 struct { 181 __be16 skc_dport; 182 __u16 skc_num; 183 }; 184 }; 185 186 unsigned short skc_family; 187 volatile unsigned char skc_state; 188 unsigned char skc_reuse:4; 189 unsigned char skc_reuseport:1; 190 unsigned char skc_ipv6only:1; 191 unsigned char skc_net_refcnt:1; 192 int skc_bound_dev_if; 193 union { 194 struct hlist_node skc_bind_node; 195 struct hlist_node skc_portaddr_node; 196 }; 197 struct proto *skc_prot; 198 possible_net_t skc_net; 199 200 #if IS_ENABLED(CONFIG_IPV6) 201 struct in6_addr skc_v6_daddr; 202 struct in6_addr skc_v6_rcv_saddr; 203 #endif 204 205 atomic64_t skc_cookie; 206 207 /* following fields are padding to force 208 * offset(struct sock, sk_refcnt) == 128 on 64bit arches 209 * assuming IPV6 is enabled. We use this padding differently 210 * for different kind of 'sockets' 211 */ 212 union { 213 unsigned long skc_flags; 214 struct sock *skc_listener; /* request_sock */ 215 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */ 216 }; 217 /* 218 * fields between dontcopy_begin/dontcopy_end 219 * are not copied in sock_copy() 220 */ 221 /* private: */ 222 int skc_dontcopy_begin[0]; 223 /* public: */ 224 union { 225 struct hlist_node skc_node; 226 struct hlist_nulls_node skc_nulls_node; 227 }; 228 unsigned short skc_tx_queue_mapping; 229 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 230 unsigned short skc_rx_queue_mapping; 231 #endif 232 union { 233 int skc_incoming_cpu; 234 u32 skc_rcv_wnd; 235 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */ 236 }; 237 238 refcount_t skc_refcnt; 239 /* private: */ 240 int skc_dontcopy_end[0]; 241 union { 242 u32 skc_rxhash; 243 u32 skc_window_clamp; 244 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */ 245 }; 246 /* public: */ 247 }; 248 249 struct bpf_local_storage; 250 251 /** 252 * struct sock - network layer representation of sockets 253 * @__sk_common: shared layout with inet_timewait_sock 254 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN 255 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings 256 * @sk_lock: synchronizer 257 * @sk_kern_sock: True if sock is using kernel lock classes 258 * @sk_rcvbuf: size of receive buffer in bytes 259 * @sk_wq: sock wait queue and async head 260 * @sk_rx_dst: receive input route used by early demux 261 * @sk_dst_cache: destination cache 262 * @sk_dst_pending_confirm: need to confirm neighbour 263 * @sk_policy: flow policy 264 * @sk_rx_skb_cache: cache copy of recently accessed RX skb 265 * @sk_receive_queue: incoming packets 266 * @sk_wmem_alloc: transmit queue bytes committed 267 * @sk_tsq_flags: TCP Small Queues flags 268 * @sk_write_queue: Packet sending queue 269 * @sk_omem_alloc: "o" is "option" or "other" 270 * @sk_wmem_queued: persistent queue size 271 * @sk_forward_alloc: space allocated forward 272 * @sk_napi_id: id of the last napi context to receive data for sk 273 * @sk_ll_usec: usecs to busypoll when there is no data 274 * @sk_allocation: allocation mode 275 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler) 276 * @sk_pacing_status: Pacing status (requested, handled by sch_fq) 277 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE) 278 * @sk_sndbuf: size of send buffer in bytes 279 * @__sk_flags_offset: empty field used to determine location of bitfield 280 * @sk_padding: unused element for alignment 281 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets 282 * @sk_no_check_rx: allow zero checksum in RX packets 283 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) 284 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK) 285 * @sk_route_forced_caps: static, forced route capabilities 286 * (set in tcp_init_sock()) 287 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) 288 * @sk_gso_max_size: Maximum GSO segment size to build 289 * @sk_gso_max_segs: Maximum number of GSO segments 290 * @sk_pacing_shift: scaling factor for TCP Small Queues 291 * @sk_lingertime: %SO_LINGER l_linger setting 292 * @sk_backlog: always used with the per-socket spinlock held 293 * @sk_callback_lock: used with the callbacks in the end of this struct 294 * @sk_error_queue: rarely used 295 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, 296 * IPV6_ADDRFORM for instance) 297 * @sk_err: last error 298 * @sk_err_soft: errors that don't cause failure but are the cause of a 299 * persistent failure not just 'timed out' 300 * @sk_drops: raw/udp drops counter 301 * @sk_ack_backlog: current listen backlog 302 * @sk_max_ack_backlog: listen backlog set in listen() 303 * @sk_uid: user id of owner 304 * @sk_prefer_busy_poll: prefer busypolling over softirq processing 305 * @sk_busy_poll_budget: napi processing budget when busypolling 306 * @sk_priority: %SO_PRIORITY setting 307 * @sk_type: socket type (%SOCK_STREAM, etc) 308 * @sk_protocol: which protocol this socket belongs in this network family 309 * @sk_peer_pid: &struct pid for this socket's peer 310 * @sk_peer_cred: %SO_PEERCRED setting 311 * @sk_rcvlowat: %SO_RCVLOWAT setting 312 * @sk_rcvtimeo: %SO_RCVTIMEO setting 313 * @sk_sndtimeo: %SO_SNDTIMEO setting 314 * @sk_txhash: computed flow hash for use on transmit 315 * @sk_filter: socket filtering instructions 316 * @sk_timer: sock cleanup timer 317 * @sk_stamp: time stamp of last packet received 318 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only 319 * @sk_tsflags: SO_TIMESTAMPING socket options 320 * @sk_tskey: counter to disambiguate concurrent tstamp requests 321 * @sk_zckey: counter to order MSG_ZEROCOPY notifications 322 * @sk_socket: Identd and reporting IO signals 323 * @sk_user_data: RPC layer private data 324 * @sk_frag: cached page frag 325 * @sk_peek_off: current peek_offset value 326 * @sk_send_head: front of stuff to transmit 327 * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head] 328 * @sk_tx_skb_cache: cache copy of recently accessed TX skb 329 * @sk_security: used by security modules 330 * @sk_mark: generic packet mark 331 * @sk_cgrp_data: cgroup data for this cgroup 332 * @sk_memcg: this socket's memory cgroup association 333 * @sk_write_pending: a write to stream socket waits to start 334 * @sk_state_change: callback to indicate change in the state of the sock 335 * @sk_data_ready: callback to indicate there is data to be processed 336 * @sk_write_space: callback to indicate there is bf sending space available 337 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) 338 * @sk_backlog_rcv: callback to process the backlog 339 * @sk_validate_xmit_skb: ptr to an optional validate function 340 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 341 * @sk_reuseport_cb: reuseport group container 342 * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage 343 * @sk_rcu: used during RCU grace period 344 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) 345 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME 346 * @sk_txtime_report_errors: set report errors mode for SO_TXTIME 347 * @sk_txtime_unused: unused txtime flags 348 */ 349 struct sock { 350 /* 351 * Now struct inet_timewait_sock also uses sock_common, so please just 352 * don't add nothing before this first member (__sk_common) --acme 353 */ 354 struct sock_common __sk_common; 355 #define sk_node __sk_common.skc_node 356 #define sk_nulls_node __sk_common.skc_nulls_node 357 #define sk_refcnt __sk_common.skc_refcnt 358 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping 359 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 360 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping 361 #endif 362 363 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin 364 #define sk_dontcopy_end __sk_common.skc_dontcopy_end 365 #define sk_hash __sk_common.skc_hash 366 #define sk_portpair __sk_common.skc_portpair 367 #define sk_num __sk_common.skc_num 368 #define sk_dport __sk_common.skc_dport 369 #define sk_addrpair __sk_common.skc_addrpair 370 #define sk_daddr __sk_common.skc_daddr 371 #define sk_rcv_saddr __sk_common.skc_rcv_saddr 372 #define sk_family __sk_common.skc_family 373 #define sk_state __sk_common.skc_state 374 #define sk_reuse __sk_common.skc_reuse 375 #define sk_reuseport __sk_common.skc_reuseport 376 #define sk_ipv6only __sk_common.skc_ipv6only 377 #define sk_net_refcnt __sk_common.skc_net_refcnt 378 #define sk_bound_dev_if __sk_common.skc_bound_dev_if 379 #define sk_bind_node __sk_common.skc_bind_node 380 #define sk_prot __sk_common.skc_prot 381 #define sk_net __sk_common.skc_net 382 #define sk_v6_daddr __sk_common.skc_v6_daddr 383 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr 384 #define sk_cookie __sk_common.skc_cookie 385 #define sk_incoming_cpu __sk_common.skc_incoming_cpu 386 #define sk_flags __sk_common.skc_flags 387 #define sk_rxhash __sk_common.skc_rxhash 388 389 socket_lock_t sk_lock; 390 atomic_t sk_drops; 391 int sk_rcvlowat; 392 struct sk_buff_head sk_error_queue; 393 struct sk_buff *sk_rx_skb_cache; 394 struct sk_buff_head sk_receive_queue; 395 /* 396 * The backlog queue is special, it is always used with 397 * the per-socket spinlock held and requires low latency 398 * access. Therefore we special case it's implementation. 399 * Note : rmem_alloc is in this structure to fill a hole 400 * on 64bit arches, not because its logically part of 401 * backlog. 402 */ 403 struct { 404 atomic_t rmem_alloc; 405 int len; 406 struct sk_buff *head; 407 struct sk_buff *tail; 408 } sk_backlog; 409 #define sk_rmem_alloc sk_backlog.rmem_alloc 410 411 int sk_forward_alloc; 412 #ifdef CONFIG_NET_RX_BUSY_POLL 413 unsigned int sk_ll_usec; 414 /* ===== mostly read cache line ===== */ 415 unsigned int sk_napi_id; 416 #endif 417 int sk_rcvbuf; 418 419 struct sk_filter __rcu *sk_filter; 420 union { 421 struct socket_wq __rcu *sk_wq; 422 /* private: */ 423 struct socket_wq *sk_wq_raw; 424 /* public: */ 425 }; 426 #ifdef CONFIG_XFRM 427 struct xfrm_policy __rcu *sk_policy[2]; 428 #endif 429 struct dst_entry *sk_rx_dst; 430 struct dst_entry __rcu *sk_dst_cache; 431 atomic_t sk_omem_alloc; 432 int sk_sndbuf; 433 434 /* ===== cache line for TX ===== */ 435 int sk_wmem_queued; 436 refcount_t sk_wmem_alloc; 437 unsigned long sk_tsq_flags; 438 union { 439 struct sk_buff *sk_send_head; 440 struct rb_root tcp_rtx_queue; 441 }; 442 struct sk_buff *sk_tx_skb_cache; 443 struct sk_buff_head sk_write_queue; 444 __s32 sk_peek_off; 445 int sk_write_pending; 446 __u32 sk_dst_pending_confirm; 447 u32 sk_pacing_status; /* see enum sk_pacing */ 448 long sk_sndtimeo; 449 struct timer_list sk_timer; 450 __u32 sk_priority; 451 __u32 sk_mark; 452 unsigned long sk_pacing_rate; /* bytes per second */ 453 unsigned long sk_max_pacing_rate; 454 struct page_frag sk_frag; 455 netdev_features_t sk_route_caps; 456 netdev_features_t sk_route_nocaps; 457 netdev_features_t sk_route_forced_caps; 458 int sk_gso_type; 459 unsigned int sk_gso_max_size; 460 gfp_t sk_allocation; 461 __u32 sk_txhash; 462 463 /* 464 * Because of non atomicity rules, all 465 * changes are protected by socket lock. 466 */ 467 u8 sk_padding : 1, 468 sk_kern_sock : 1, 469 sk_no_check_tx : 1, 470 sk_no_check_rx : 1, 471 sk_userlocks : 4; 472 u8 sk_pacing_shift; 473 u16 sk_type; 474 u16 sk_protocol; 475 u16 sk_gso_max_segs; 476 unsigned long sk_lingertime; 477 struct proto *sk_prot_creator; 478 rwlock_t sk_callback_lock; 479 int sk_err, 480 sk_err_soft; 481 u32 sk_ack_backlog; 482 u32 sk_max_ack_backlog; 483 kuid_t sk_uid; 484 #ifdef CONFIG_NET_RX_BUSY_POLL 485 u8 sk_prefer_busy_poll; 486 u16 sk_busy_poll_budget; 487 #endif 488 struct pid *sk_peer_pid; 489 const struct cred *sk_peer_cred; 490 long sk_rcvtimeo; 491 ktime_t sk_stamp; 492 #if BITS_PER_LONG==32 493 seqlock_t sk_stamp_seq; 494 #endif 495 u16 sk_tsflags; 496 u8 sk_shutdown; 497 u32 sk_tskey; 498 atomic_t sk_zckey; 499 500 u8 sk_clockid; 501 u8 sk_txtime_deadline_mode : 1, 502 sk_txtime_report_errors : 1, 503 sk_txtime_unused : 6; 504 505 struct socket *sk_socket; 506 void *sk_user_data; 507 #ifdef CONFIG_SECURITY 508 void *sk_security; 509 #endif 510 struct sock_cgroup_data sk_cgrp_data; 511 struct mem_cgroup *sk_memcg; 512 void (*sk_state_change)(struct sock *sk); 513 void (*sk_data_ready)(struct sock *sk); 514 void (*sk_write_space)(struct sock *sk); 515 void (*sk_error_report)(struct sock *sk); 516 int (*sk_backlog_rcv)(struct sock *sk, 517 struct sk_buff *skb); 518 #ifdef CONFIG_SOCK_VALIDATE_XMIT 519 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk, 520 struct net_device *dev, 521 struct sk_buff *skb); 522 #endif 523 void (*sk_destruct)(struct sock *sk); 524 struct sock_reuseport __rcu *sk_reuseport_cb; 525 #ifdef CONFIG_BPF_SYSCALL 526 struct bpf_local_storage __rcu *sk_bpf_storage; 527 #endif 528 struct rcu_head sk_rcu; 529 }; 530 531 enum sk_pacing { 532 SK_PACING_NONE = 0, 533 SK_PACING_NEEDED = 1, 534 SK_PACING_FQ = 2, 535 }; 536 537 /* Pointer stored in sk_user_data might not be suitable for copying 538 * when cloning the socket. For instance, it can point to a reference 539 * counted object. sk_user_data bottom bit is set if pointer must not 540 * be copied. 541 */ 542 #define SK_USER_DATA_NOCOPY 1UL 543 #define SK_USER_DATA_BPF 2UL /* Managed by BPF */ 544 #define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF) 545 546 /** 547 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied 548 * @sk: socket 549 */ 550 static inline bool sk_user_data_is_nocopy(const struct sock *sk) 551 { 552 return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY); 553 } 554 555 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data))) 556 557 #define rcu_dereference_sk_user_data(sk) \ 558 ({ \ 559 void *__tmp = rcu_dereference(__sk_user_data((sk))); \ 560 (void *)((uintptr_t)__tmp & SK_USER_DATA_PTRMASK); \ 561 }) 562 #define rcu_assign_sk_user_data(sk, ptr) \ 563 ({ \ 564 uintptr_t __tmp = (uintptr_t)(ptr); \ 565 WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \ 566 rcu_assign_pointer(__sk_user_data((sk)), __tmp); \ 567 }) 568 #define rcu_assign_sk_user_data_nocopy(sk, ptr) \ 569 ({ \ 570 uintptr_t __tmp = (uintptr_t)(ptr); \ 571 WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \ 572 rcu_assign_pointer(__sk_user_data((sk)), \ 573 __tmp | SK_USER_DATA_NOCOPY); \ 574 }) 575 576 /* 577 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK 578 * or not whether his port will be reused by someone else. SK_FORCE_REUSE 579 * on a socket means that the socket will reuse everybody else's port 580 * without looking at the other's sk_reuse value. 581 */ 582 583 #define SK_NO_REUSE 0 584 #define SK_CAN_REUSE 1 585 #define SK_FORCE_REUSE 2 586 587 int sk_set_peek_off(struct sock *sk, int val); 588 589 static inline int sk_peek_offset(struct sock *sk, int flags) 590 { 591 if (unlikely(flags & MSG_PEEK)) { 592 return READ_ONCE(sk->sk_peek_off); 593 } 594 595 return 0; 596 } 597 598 static inline void sk_peek_offset_bwd(struct sock *sk, int val) 599 { 600 s32 off = READ_ONCE(sk->sk_peek_off); 601 602 if (unlikely(off >= 0)) { 603 off = max_t(s32, off - val, 0); 604 WRITE_ONCE(sk->sk_peek_off, off); 605 } 606 } 607 608 static inline void sk_peek_offset_fwd(struct sock *sk, int val) 609 { 610 sk_peek_offset_bwd(sk, -val); 611 } 612 613 /* 614 * Hashed lists helper routines 615 */ 616 static inline struct sock *sk_entry(const struct hlist_node *node) 617 { 618 return hlist_entry(node, struct sock, sk_node); 619 } 620 621 static inline struct sock *__sk_head(const struct hlist_head *head) 622 { 623 return hlist_entry(head->first, struct sock, sk_node); 624 } 625 626 static inline struct sock *sk_head(const struct hlist_head *head) 627 { 628 return hlist_empty(head) ? NULL : __sk_head(head); 629 } 630 631 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) 632 { 633 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); 634 } 635 636 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) 637 { 638 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); 639 } 640 641 static inline struct sock *sk_next(const struct sock *sk) 642 { 643 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node); 644 } 645 646 static inline struct sock *sk_nulls_next(const struct sock *sk) 647 { 648 return (!is_a_nulls(sk->sk_nulls_node.next)) ? 649 hlist_nulls_entry(sk->sk_nulls_node.next, 650 struct sock, sk_nulls_node) : 651 NULL; 652 } 653 654 static inline bool sk_unhashed(const struct sock *sk) 655 { 656 return hlist_unhashed(&sk->sk_node); 657 } 658 659 static inline bool sk_hashed(const struct sock *sk) 660 { 661 return !sk_unhashed(sk); 662 } 663 664 static inline void sk_node_init(struct hlist_node *node) 665 { 666 node->pprev = NULL; 667 } 668 669 static inline void sk_nulls_node_init(struct hlist_nulls_node *node) 670 { 671 node->pprev = NULL; 672 } 673 674 static inline void __sk_del_node(struct sock *sk) 675 { 676 __hlist_del(&sk->sk_node); 677 } 678 679 /* NB: equivalent to hlist_del_init_rcu */ 680 static inline bool __sk_del_node_init(struct sock *sk) 681 { 682 if (sk_hashed(sk)) { 683 __sk_del_node(sk); 684 sk_node_init(&sk->sk_node); 685 return true; 686 } 687 return false; 688 } 689 690 /* Grab socket reference count. This operation is valid only 691 when sk is ALREADY grabbed f.e. it is found in hash table 692 or a list and the lookup is made under lock preventing hash table 693 modifications. 694 */ 695 696 static __always_inline void sock_hold(struct sock *sk) 697 { 698 refcount_inc(&sk->sk_refcnt); 699 } 700 701 /* Ungrab socket in the context, which assumes that socket refcnt 702 cannot hit zero, f.e. it is true in context of any socketcall. 703 */ 704 static __always_inline void __sock_put(struct sock *sk) 705 { 706 refcount_dec(&sk->sk_refcnt); 707 } 708 709 static inline bool sk_del_node_init(struct sock *sk) 710 { 711 bool rc = __sk_del_node_init(sk); 712 713 if (rc) { 714 /* paranoid for a while -acme */ 715 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 716 __sock_put(sk); 717 } 718 return rc; 719 } 720 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk) 721 722 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk) 723 { 724 if (sk_hashed(sk)) { 725 hlist_nulls_del_init_rcu(&sk->sk_nulls_node); 726 return true; 727 } 728 return false; 729 } 730 731 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) 732 { 733 bool rc = __sk_nulls_del_node_init_rcu(sk); 734 735 if (rc) { 736 /* paranoid for a while -acme */ 737 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 738 __sock_put(sk); 739 } 740 return rc; 741 } 742 743 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list) 744 { 745 hlist_add_head(&sk->sk_node, list); 746 } 747 748 static inline void sk_add_node(struct sock *sk, struct hlist_head *list) 749 { 750 sock_hold(sk); 751 __sk_add_node(sk, list); 752 } 753 754 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list) 755 { 756 sock_hold(sk); 757 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && 758 sk->sk_family == AF_INET6) 759 hlist_add_tail_rcu(&sk->sk_node, list); 760 else 761 hlist_add_head_rcu(&sk->sk_node, list); 762 } 763 764 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list) 765 { 766 sock_hold(sk); 767 hlist_add_tail_rcu(&sk->sk_node, list); 768 } 769 770 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 771 { 772 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); 773 } 774 775 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list) 776 { 777 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list); 778 } 779 780 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 781 { 782 sock_hold(sk); 783 __sk_nulls_add_node_rcu(sk, list); 784 } 785 786 static inline void __sk_del_bind_node(struct sock *sk) 787 { 788 __hlist_del(&sk->sk_bind_node); 789 } 790 791 static inline void sk_add_bind_node(struct sock *sk, 792 struct hlist_head *list) 793 { 794 hlist_add_head(&sk->sk_bind_node, list); 795 } 796 797 #define sk_for_each(__sk, list) \ 798 hlist_for_each_entry(__sk, list, sk_node) 799 #define sk_for_each_rcu(__sk, list) \ 800 hlist_for_each_entry_rcu(__sk, list, sk_node) 801 #define sk_nulls_for_each(__sk, node, list) \ 802 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) 803 #define sk_nulls_for_each_rcu(__sk, node, list) \ 804 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) 805 #define sk_for_each_from(__sk) \ 806 hlist_for_each_entry_from(__sk, sk_node) 807 #define sk_nulls_for_each_from(__sk, node) \ 808 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ 809 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) 810 #define sk_for_each_safe(__sk, tmp, list) \ 811 hlist_for_each_entry_safe(__sk, tmp, list, sk_node) 812 #define sk_for_each_bound(__sk, list) \ 813 hlist_for_each_entry(__sk, list, sk_bind_node) 814 815 /** 816 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset 817 * @tpos: the type * to use as a loop cursor. 818 * @pos: the &struct hlist_node to use as a loop cursor. 819 * @head: the head for your list. 820 * @offset: offset of hlist_node within the struct. 821 * 822 */ 823 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \ 824 for (pos = rcu_dereference(hlist_first_rcu(head)); \ 825 pos != NULL && \ 826 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ 827 pos = rcu_dereference(hlist_next_rcu(pos))) 828 829 static inline struct user_namespace *sk_user_ns(struct sock *sk) 830 { 831 /* Careful only use this in a context where these parameters 832 * can not change and must all be valid, such as recvmsg from 833 * userspace. 834 */ 835 return sk->sk_socket->file->f_cred->user_ns; 836 } 837 838 /* Sock flags */ 839 enum sock_flags { 840 SOCK_DEAD, 841 SOCK_DONE, 842 SOCK_URGINLINE, 843 SOCK_KEEPOPEN, 844 SOCK_LINGER, 845 SOCK_DESTROY, 846 SOCK_BROADCAST, 847 SOCK_TIMESTAMP, 848 SOCK_ZAPPED, 849 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 850 SOCK_DBG, /* %SO_DEBUG setting */ 851 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 852 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 853 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 854 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 855 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 856 SOCK_FASYNC, /* fasync() active */ 857 SOCK_RXQ_OVFL, 858 SOCK_ZEROCOPY, /* buffers from userspace */ 859 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 860 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 861 * Will use last 4 bytes of packet sent from 862 * user-space instead. 863 */ 864 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ 865 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ 866 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ 867 SOCK_TXTIME, 868 SOCK_XDP, /* XDP is attached */ 869 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ 870 }; 871 872 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 873 874 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk) 875 { 876 nsk->sk_flags = osk->sk_flags; 877 } 878 879 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 880 { 881 __set_bit(flag, &sk->sk_flags); 882 } 883 884 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 885 { 886 __clear_bit(flag, &sk->sk_flags); 887 } 888 889 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit, 890 int valbool) 891 { 892 if (valbool) 893 sock_set_flag(sk, bit); 894 else 895 sock_reset_flag(sk, bit); 896 } 897 898 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 899 { 900 return test_bit(flag, &sk->sk_flags); 901 } 902 903 #ifdef CONFIG_NET 904 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key); 905 static inline int sk_memalloc_socks(void) 906 { 907 return static_branch_unlikely(&memalloc_socks_key); 908 } 909 910 void __receive_sock(struct file *file); 911 #else 912 913 static inline int sk_memalloc_socks(void) 914 { 915 return 0; 916 } 917 918 static inline void __receive_sock(struct file *file) 919 { } 920 #endif 921 922 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask) 923 { 924 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC); 925 } 926 927 static inline void sk_acceptq_removed(struct sock *sk) 928 { 929 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1); 930 } 931 932 static inline void sk_acceptq_added(struct sock *sk) 933 { 934 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1); 935 } 936 937 /* Note: If you think the test should be: 938 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog); 939 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.") 940 */ 941 static inline bool sk_acceptq_is_full(const struct sock *sk) 942 { 943 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog); 944 } 945 946 /* 947 * Compute minimal free write space needed to queue new packets. 948 */ 949 static inline int sk_stream_min_wspace(const struct sock *sk) 950 { 951 return READ_ONCE(sk->sk_wmem_queued) >> 1; 952 } 953 954 static inline int sk_stream_wspace(const struct sock *sk) 955 { 956 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued); 957 } 958 959 static inline void sk_wmem_queued_add(struct sock *sk, int val) 960 { 961 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val); 962 } 963 964 void sk_stream_write_space(struct sock *sk); 965 966 /* OOB backlog add */ 967 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 968 { 969 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 970 skb_dst_force(skb); 971 972 if (!sk->sk_backlog.tail) 973 WRITE_ONCE(sk->sk_backlog.head, skb); 974 else 975 sk->sk_backlog.tail->next = skb; 976 977 WRITE_ONCE(sk->sk_backlog.tail, skb); 978 skb->next = NULL; 979 } 980 981 /* 982 * Take into account size of receive queue and backlog queue 983 * Do not take into account this skb truesize, 984 * to allow even a single big packet to come. 985 */ 986 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit) 987 { 988 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 989 990 return qsize > limit; 991 } 992 993 /* The per-socket spinlock must be held here. */ 994 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 995 unsigned int limit) 996 { 997 if (sk_rcvqueues_full(sk, limit)) 998 return -ENOBUFS; 999 1000 /* 1001 * If the skb was allocated from pfmemalloc reserves, only 1002 * allow SOCK_MEMALLOC sockets to use it as this socket is 1003 * helping free memory 1004 */ 1005 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) 1006 return -ENOMEM; 1007 1008 __sk_add_backlog(sk, skb); 1009 sk->sk_backlog.len += skb->truesize; 1010 return 0; 1011 } 1012 1013 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 1014 1015 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 1016 { 1017 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 1018 return __sk_backlog_rcv(sk, skb); 1019 1020 return sk->sk_backlog_rcv(sk, skb); 1021 } 1022 1023 static inline void sk_incoming_cpu_update(struct sock *sk) 1024 { 1025 int cpu = raw_smp_processor_id(); 1026 1027 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu)) 1028 WRITE_ONCE(sk->sk_incoming_cpu, cpu); 1029 } 1030 1031 static inline void sock_rps_record_flow_hash(__u32 hash) 1032 { 1033 #ifdef CONFIG_RPS 1034 struct rps_sock_flow_table *sock_flow_table; 1035 1036 rcu_read_lock(); 1037 sock_flow_table = rcu_dereference(rps_sock_flow_table); 1038 rps_record_sock_flow(sock_flow_table, hash); 1039 rcu_read_unlock(); 1040 #endif 1041 } 1042 1043 static inline void sock_rps_record_flow(const struct sock *sk) 1044 { 1045 #ifdef CONFIG_RPS 1046 if (static_branch_unlikely(&rfs_needed)) { 1047 /* Reading sk->sk_rxhash might incur an expensive cache line 1048 * miss. 1049 * 1050 * TCP_ESTABLISHED does cover almost all states where RFS 1051 * might be useful, and is cheaper [1] than testing : 1052 * IPv4: inet_sk(sk)->inet_daddr 1053 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr) 1054 * OR an additional socket flag 1055 * [1] : sk_state and sk_prot are in the same cache line. 1056 */ 1057 if (sk->sk_state == TCP_ESTABLISHED) 1058 sock_rps_record_flow_hash(sk->sk_rxhash); 1059 } 1060 #endif 1061 } 1062 1063 static inline void sock_rps_save_rxhash(struct sock *sk, 1064 const struct sk_buff *skb) 1065 { 1066 #ifdef CONFIG_RPS 1067 if (unlikely(sk->sk_rxhash != skb->hash)) 1068 sk->sk_rxhash = skb->hash; 1069 #endif 1070 } 1071 1072 static inline void sock_rps_reset_rxhash(struct sock *sk) 1073 { 1074 #ifdef CONFIG_RPS 1075 sk->sk_rxhash = 0; 1076 #endif 1077 } 1078 1079 #define sk_wait_event(__sk, __timeo, __condition, __wait) \ 1080 ({ int __rc; \ 1081 release_sock(__sk); \ 1082 __rc = __condition; \ 1083 if (!__rc) { \ 1084 *(__timeo) = wait_woken(__wait, \ 1085 TASK_INTERRUPTIBLE, \ 1086 *(__timeo)); \ 1087 } \ 1088 sched_annotate_sleep(); \ 1089 lock_sock(__sk); \ 1090 __rc = __condition; \ 1091 __rc; \ 1092 }) 1093 1094 int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 1095 int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 1096 void sk_stream_wait_close(struct sock *sk, long timeo_p); 1097 int sk_stream_error(struct sock *sk, int flags, int err); 1098 void sk_stream_kill_queues(struct sock *sk); 1099 void sk_set_memalloc(struct sock *sk); 1100 void sk_clear_memalloc(struct sock *sk); 1101 1102 void __sk_flush_backlog(struct sock *sk); 1103 1104 static inline bool sk_flush_backlog(struct sock *sk) 1105 { 1106 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) { 1107 __sk_flush_backlog(sk); 1108 return true; 1109 } 1110 return false; 1111 } 1112 1113 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb); 1114 1115 struct request_sock_ops; 1116 struct timewait_sock_ops; 1117 struct inet_hashinfo; 1118 struct raw_hashinfo; 1119 struct smc_hashinfo; 1120 struct module; 1121 struct sk_psock; 1122 1123 /* 1124 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes 1125 * un-modified. Special care is taken when initializing object to zero. 1126 */ 1127 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1128 { 1129 if (offsetof(struct sock, sk_node.next) != 0) 1130 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1131 memset(&sk->sk_node.pprev, 0, 1132 size - offsetof(struct sock, sk_node.pprev)); 1133 } 1134 1135 /* Networking protocol blocks we attach to sockets. 1136 * socket layer -> transport layer interface 1137 */ 1138 struct proto { 1139 void (*close)(struct sock *sk, 1140 long timeout); 1141 int (*pre_connect)(struct sock *sk, 1142 struct sockaddr *uaddr, 1143 int addr_len); 1144 int (*connect)(struct sock *sk, 1145 struct sockaddr *uaddr, 1146 int addr_len); 1147 int (*disconnect)(struct sock *sk, int flags); 1148 1149 struct sock * (*accept)(struct sock *sk, int flags, int *err, 1150 bool kern); 1151 1152 int (*ioctl)(struct sock *sk, int cmd, 1153 unsigned long arg); 1154 int (*init)(struct sock *sk); 1155 void (*destroy)(struct sock *sk); 1156 void (*shutdown)(struct sock *sk, int how); 1157 int (*setsockopt)(struct sock *sk, int level, 1158 int optname, sockptr_t optval, 1159 unsigned int optlen); 1160 int (*getsockopt)(struct sock *sk, int level, 1161 int optname, char __user *optval, 1162 int __user *option); 1163 void (*keepalive)(struct sock *sk, int valbool); 1164 #ifdef CONFIG_COMPAT 1165 int (*compat_ioctl)(struct sock *sk, 1166 unsigned int cmd, unsigned long arg); 1167 #endif 1168 int (*sendmsg)(struct sock *sk, struct msghdr *msg, 1169 size_t len); 1170 int (*recvmsg)(struct sock *sk, struct msghdr *msg, 1171 size_t len, int noblock, int flags, 1172 int *addr_len); 1173 int (*sendpage)(struct sock *sk, struct page *page, 1174 int offset, size_t size, int flags); 1175 int (*bind)(struct sock *sk, 1176 struct sockaddr *addr, int addr_len); 1177 int (*bind_add)(struct sock *sk, 1178 struct sockaddr *addr, int addr_len); 1179 1180 int (*backlog_rcv) (struct sock *sk, 1181 struct sk_buff *skb); 1182 bool (*bpf_bypass_getsockopt)(int level, 1183 int optname); 1184 1185 void (*release_cb)(struct sock *sk); 1186 1187 /* Keeping track of sk's, looking them up, and port selection methods. */ 1188 int (*hash)(struct sock *sk); 1189 void (*unhash)(struct sock *sk); 1190 void (*rehash)(struct sock *sk); 1191 int (*get_port)(struct sock *sk, unsigned short snum); 1192 #ifdef CONFIG_BPF_SYSCALL 1193 int (*psock_update_sk_prot)(struct sock *sk, 1194 struct sk_psock *psock, 1195 bool restore); 1196 #endif 1197 1198 /* Keeping track of sockets in use */ 1199 #ifdef CONFIG_PROC_FS 1200 unsigned int inuse_idx; 1201 #endif 1202 1203 bool (*stream_memory_free)(const struct sock *sk, int wake); 1204 bool (*stream_memory_read)(const struct sock *sk); 1205 /* Memory pressure */ 1206 void (*enter_memory_pressure)(struct sock *sk); 1207 void (*leave_memory_pressure)(struct sock *sk); 1208 atomic_long_t *memory_allocated; /* Current allocated memory. */ 1209 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 1210 /* 1211 * Pressure flag: try to collapse. 1212 * Technical note: it is used by multiple contexts non atomically. 1213 * All the __sk_mem_schedule() is of this nature: accounting 1214 * is strict, actions are advisory and have some latency. 1215 */ 1216 unsigned long *memory_pressure; 1217 long *sysctl_mem; 1218 1219 int *sysctl_wmem; 1220 int *sysctl_rmem; 1221 u32 sysctl_wmem_offset; 1222 u32 sysctl_rmem_offset; 1223 1224 int max_header; 1225 bool no_autobind; 1226 1227 struct kmem_cache *slab; 1228 unsigned int obj_size; 1229 slab_flags_t slab_flags; 1230 unsigned int useroffset; /* Usercopy region offset */ 1231 unsigned int usersize; /* Usercopy region size */ 1232 1233 struct percpu_counter *orphan_count; 1234 1235 struct request_sock_ops *rsk_prot; 1236 struct timewait_sock_ops *twsk_prot; 1237 1238 union { 1239 struct inet_hashinfo *hashinfo; 1240 struct udp_table *udp_table; 1241 struct raw_hashinfo *raw_hash; 1242 struct smc_hashinfo *smc_hash; 1243 } h; 1244 1245 struct module *owner; 1246 1247 char name[32]; 1248 1249 struct list_head node; 1250 #ifdef SOCK_REFCNT_DEBUG 1251 atomic_t socks; 1252 #endif 1253 int (*diag_destroy)(struct sock *sk, int err); 1254 } __randomize_layout; 1255 1256 int proto_register(struct proto *prot, int alloc_slab); 1257 void proto_unregister(struct proto *prot); 1258 int sock_load_diag_module(int family, int protocol); 1259 1260 #ifdef SOCK_REFCNT_DEBUG 1261 static inline void sk_refcnt_debug_inc(struct sock *sk) 1262 { 1263 atomic_inc(&sk->sk_prot->socks); 1264 } 1265 1266 static inline void sk_refcnt_debug_dec(struct sock *sk) 1267 { 1268 atomic_dec(&sk->sk_prot->socks); 1269 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n", 1270 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks)); 1271 } 1272 1273 static inline void sk_refcnt_debug_release(const struct sock *sk) 1274 { 1275 if (refcount_read(&sk->sk_refcnt) != 1) 1276 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n", 1277 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt)); 1278 } 1279 #else /* SOCK_REFCNT_DEBUG */ 1280 #define sk_refcnt_debug_inc(sk) do { } while (0) 1281 #define sk_refcnt_debug_dec(sk) do { } while (0) 1282 #define sk_refcnt_debug_release(sk) do { } while (0) 1283 #endif /* SOCK_REFCNT_DEBUG */ 1284 1285 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake)); 1286 1287 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake) 1288 { 1289 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf)) 1290 return false; 1291 1292 #ifdef CONFIG_INET 1293 return sk->sk_prot->stream_memory_free ? 1294 INDIRECT_CALL_1(sk->sk_prot->stream_memory_free, 1295 tcp_stream_memory_free, 1296 sk, wake) : true; 1297 #else 1298 return sk->sk_prot->stream_memory_free ? 1299 sk->sk_prot->stream_memory_free(sk, wake) : true; 1300 #endif 1301 } 1302 1303 static inline bool sk_stream_memory_free(const struct sock *sk) 1304 { 1305 return __sk_stream_memory_free(sk, 0); 1306 } 1307 1308 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake) 1309 { 1310 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && 1311 __sk_stream_memory_free(sk, wake); 1312 } 1313 1314 static inline bool sk_stream_is_writeable(const struct sock *sk) 1315 { 1316 return __sk_stream_is_writeable(sk, 0); 1317 } 1318 1319 static inline int sk_under_cgroup_hierarchy(struct sock *sk, 1320 struct cgroup *ancestor) 1321 { 1322 #ifdef CONFIG_SOCK_CGROUP_DATA 1323 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data), 1324 ancestor); 1325 #else 1326 return -ENOTSUPP; 1327 #endif 1328 } 1329 1330 static inline bool sk_has_memory_pressure(const struct sock *sk) 1331 { 1332 return sk->sk_prot->memory_pressure != NULL; 1333 } 1334 1335 static inline bool sk_under_memory_pressure(const struct sock *sk) 1336 { 1337 if (!sk->sk_prot->memory_pressure) 1338 return false; 1339 1340 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 1341 mem_cgroup_under_socket_pressure(sk->sk_memcg)) 1342 return true; 1343 1344 return !!*sk->sk_prot->memory_pressure; 1345 } 1346 1347 static inline long 1348 sk_memory_allocated(const struct sock *sk) 1349 { 1350 return atomic_long_read(sk->sk_prot->memory_allocated); 1351 } 1352 1353 static inline long 1354 sk_memory_allocated_add(struct sock *sk, int amt) 1355 { 1356 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated); 1357 } 1358 1359 static inline void 1360 sk_memory_allocated_sub(struct sock *sk, int amt) 1361 { 1362 atomic_long_sub(amt, sk->sk_prot->memory_allocated); 1363 } 1364 1365 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16 1366 1367 static inline void sk_sockets_allocated_dec(struct sock *sk) 1368 { 1369 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1, 1370 SK_ALLOC_PERCPU_COUNTER_BATCH); 1371 } 1372 1373 static inline void sk_sockets_allocated_inc(struct sock *sk) 1374 { 1375 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1, 1376 SK_ALLOC_PERCPU_COUNTER_BATCH); 1377 } 1378 1379 static inline u64 1380 sk_sockets_allocated_read_positive(struct sock *sk) 1381 { 1382 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated); 1383 } 1384 1385 static inline int 1386 proto_sockets_allocated_sum_positive(struct proto *prot) 1387 { 1388 return percpu_counter_sum_positive(prot->sockets_allocated); 1389 } 1390 1391 static inline long 1392 proto_memory_allocated(struct proto *prot) 1393 { 1394 return atomic_long_read(prot->memory_allocated); 1395 } 1396 1397 static inline bool 1398 proto_memory_pressure(struct proto *prot) 1399 { 1400 if (!prot->memory_pressure) 1401 return false; 1402 return !!*prot->memory_pressure; 1403 } 1404 1405 1406 #ifdef CONFIG_PROC_FS 1407 /* Called with local bh disabled */ 1408 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); 1409 int sock_prot_inuse_get(struct net *net, struct proto *proto); 1410 int sock_inuse_get(struct net *net); 1411 #else 1412 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot, 1413 int inc) 1414 { 1415 } 1416 #endif 1417 1418 1419 /* With per-bucket locks this operation is not-atomic, so that 1420 * this version is not worse. 1421 */ 1422 static inline int __sk_prot_rehash(struct sock *sk) 1423 { 1424 sk->sk_prot->unhash(sk); 1425 return sk->sk_prot->hash(sk); 1426 } 1427 1428 /* About 10 seconds */ 1429 #define SOCK_DESTROY_TIME (10*HZ) 1430 1431 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1432 #define PROT_SOCK 1024 1433 1434 #define SHUTDOWN_MASK 3 1435 #define RCV_SHUTDOWN 1 1436 #define SEND_SHUTDOWN 2 1437 1438 #define SOCK_SNDBUF_LOCK 1 1439 #define SOCK_RCVBUF_LOCK 2 1440 #define SOCK_BINDADDR_LOCK 4 1441 #define SOCK_BINDPORT_LOCK 8 1442 1443 struct socket_alloc { 1444 struct socket socket; 1445 struct inode vfs_inode; 1446 }; 1447 1448 static inline struct socket *SOCKET_I(struct inode *inode) 1449 { 1450 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1451 } 1452 1453 static inline struct inode *SOCK_INODE(struct socket *socket) 1454 { 1455 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1456 } 1457 1458 /* 1459 * Functions for memory accounting 1460 */ 1461 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind); 1462 int __sk_mem_schedule(struct sock *sk, int size, int kind); 1463 void __sk_mem_reduce_allocated(struct sock *sk, int amount); 1464 void __sk_mem_reclaim(struct sock *sk, int amount); 1465 1466 /* We used to have PAGE_SIZE here, but systems with 64KB pages 1467 * do not necessarily have 16x time more memory than 4KB ones. 1468 */ 1469 #define SK_MEM_QUANTUM 4096 1470 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM) 1471 #define SK_MEM_SEND 0 1472 #define SK_MEM_RECV 1 1473 1474 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */ 1475 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1476 { 1477 long val = sk->sk_prot->sysctl_mem[index]; 1478 1479 #if PAGE_SIZE > SK_MEM_QUANTUM 1480 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT; 1481 #elif PAGE_SIZE < SK_MEM_QUANTUM 1482 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT; 1483 #endif 1484 return val; 1485 } 1486 1487 static inline int sk_mem_pages(int amt) 1488 { 1489 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT; 1490 } 1491 1492 static inline bool sk_has_account(struct sock *sk) 1493 { 1494 /* return true if protocol supports memory accounting */ 1495 return !!sk->sk_prot->memory_allocated; 1496 } 1497 1498 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1499 { 1500 if (!sk_has_account(sk)) 1501 return true; 1502 return size <= sk->sk_forward_alloc || 1503 __sk_mem_schedule(sk, size, SK_MEM_SEND); 1504 } 1505 1506 static inline bool 1507 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) 1508 { 1509 if (!sk_has_account(sk)) 1510 return true; 1511 return size <= sk->sk_forward_alloc || 1512 __sk_mem_schedule(sk, size, SK_MEM_RECV) || 1513 skb_pfmemalloc(skb); 1514 } 1515 1516 static inline void sk_mem_reclaim(struct sock *sk) 1517 { 1518 if (!sk_has_account(sk)) 1519 return; 1520 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM) 1521 __sk_mem_reclaim(sk, sk->sk_forward_alloc); 1522 } 1523 1524 static inline void sk_mem_reclaim_partial(struct sock *sk) 1525 { 1526 if (!sk_has_account(sk)) 1527 return; 1528 if (sk->sk_forward_alloc > SK_MEM_QUANTUM) 1529 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1); 1530 } 1531 1532 static inline void sk_mem_charge(struct sock *sk, int size) 1533 { 1534 if (!sk_has_account(sk)) 1535 return; 1536 sk->sk_forward_alloc -= size; 1537 } 1538 1539 static inline void sk_mem_uncharge(struct sock *sk, int size) 1540 { 1541 if (!sk_has_account(sk)) 1542 return; 1543 sk->sk_forward_alloc += size; 1544 1545 /* Avoid a possible overflow. 1546 * TCP send queues can make this happen, if sk_mem_reclaim() 1547 * is not called and more than 2 GBytes are released at once. 1548 * 1549 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is 1550 * no need to hold that much forward allocation anyway. 1551 */ 1552 if (unlikely(sk->sk_forward_alloc >= 1 << 21)) 1553 __sk_mem_reclaim(sk, 1 << 20); 1554 } 1555 1556 DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key); 1557 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb) 1558 { 1559 sk_wmem_queued_add(sk, -skb->truesize); 1560 sk_mem_uncharge(sk, skb->truesize); 1561 if (static_branch_unlikely(&tcp_tx_skb_cache_key) && 1562 !sk->sk_tx_skb_cache && !skb_cloned(skb)) { 1563 skb_ext_reset(skb); 1564 skb_zcopy_clear(skb, true); 1565 sk->sk_tx_skb_cache = skb; 1566 return; 1567 } 1568 __kfree_skb(skb); 1569 } 1570 1571 static inline void sock_release_ownership(struct sock *sk) 1572 { 1573 if (sk->sk_lock.owned) { 1574 sk->sk_lock.owned = 0; 1575 1576 /* The sk_lock has mutex_unlock() semantics: */ 1577 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1578 } 1579 } 1580 1581 /* 1582 * Macro so as to not evaluate some arguments when 1583 * lockdep is not enabled. 1584 * 1585 * Mark both the sk_lock and the sk_lock.slock as a 1586 * per-address-family lock class. 1587 */ 1588 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1589 do { \ 1590 sk->sk_lock.owned = 0; \ 1591 init_waitqueue_head(&sk->sk_lock.wq); \ 1592 spin_lock_init(&(sk)->sk_lock.slock); \ 1593 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1594 sizeof((sk)->sk_lock)); \ 1595 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1596 (skey), (sname)); \ 1597 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1598 } while (0) 1599 1600 static inline bool lockdep_sock_is_held(const struct sock *sk) 1601 { 1602 return lockdep_is_held(&sk->sk_lock) || 1603 lockdep_is_held(&sk->sk_lock.slock); 1604 } 1605 1606 void lock_sock_nested(struct sock *sk, int subclass); 1607 1608 static inline void lock_sock(struct sock *sk) 1609 { 1610 lock_sock_nested(sk, 0); 1611 } 1612 1613 void __lock_sock(struct sock *sk); 1614 void __release_sock(struct sock *sk); 1615 void release_sock(struct sock *sk); 1616 1617 /* BH context may only use the following locking interface. */ 1618 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1619 #define bh_lock_sock_nested(__sk) \ 1620 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1621 SINGLE_DEPTH_NESTING) 1622 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1623 1624 bool lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock); 1625 1626 /** 1627 * unlock_sock_fast - complement of lock_sock_fast 1628 * @sk: socket 1629 * @slow: slow mode 1630 * 1631 * fast unlock socket for user context. 1632 * If slow mode is on, we call regular release_sock() 1633 */ 1634 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1635 __releases(&sk->sk_lock.slock) 1636 { 1637 if (slow) { 1638 release_sock(sk); 1639 __release(&sk->sk_lock.slock); 1640 } else { 1641 spin_unlock_bh(&sk->sk_lock.slock); 1642 } 1643 } 1644 1645 /* Used by processes to "lock" a socket state, so that 1646 * interrupts and bottom half handlers won't change it 1647 * from under us. It essentially blocks any incoming 1648 * packets, so that we won't get any new data or any 1649 * packets that change the state of the socket. 1650 * 1651 * While locked, BH processing will add new packets to 1652 * the backlog queue. This queue is processed by the 1653 * owner of the socket lock right before it is released. 1654 * 1655 * Since ~2.3.5 it is also exclusive sleep lock serializing 1656 * accesses from user process context. 1657 */ 1658 1659 static inline void sock_owned_by_me(const struct sock *sk) 1660 { 1661 #ifdef CONFIG_LOCKDEP 1662 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks); 1663 #endif 1664 } 1665 1666 static inline bool sock_owned_by_user(const struct sock *sk) 1667 { 1668 sock_owned_by_me(sk); 1669 return sk->sk_lock.owned; 1670 } 1671 1672 static inline bool sock_owned_by_user_nocheck(const struct sock *sk) 1673 { 1674 return sk->sk_lock.owned; 1675 } 1676 1677 /* no reclassification while locks are held */ 1678 static inline bool sock_allow_reclassification(const struct sock *csk) 1679 { 1680 struct sock *sk = (struct sock *)csk; 1681 1682 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock); 1683 } 1684 1685 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1686 struct proto *prot, int kern); 1687 void sk_free(struct sock *sk); 1688 void sk_destruct(struct sock *sk); 1689 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); 1690 void sk_free_unlock_clone(struct sock *sk); 1691 1692 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1693 gfp_t priority); 1694 void __sock_wfree(struct sk_buff *skb); 1695 void sock_wfree(struct sk_buff *skb); 1696 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 1697 gfp_t priority); 1698 void skb_orphan_partial(struct sk_buff *skb); 1699 void sock_rfree(struct sk_buff *skb); 1700 void sock_efree(struct sk_buff *skb); 1701 #ifdef CONFIG_INET 1702 void sock_edemux(struct sk_buff *skb); 1703 void sock_pfree(struct sk_buff *skb); 1704 #else 1705 #define sock_edemux sock_efree 1706 #endif 1707 1708 int sock_setsockopt(struct socket *sock, int level, int op, 1709 sockptr_t optval, unsigned int optlen); 1710 1711 int sock_getsockopt(struct socket *sock, int level, int op, 1712 char __user *optval, int __user *optlen); 1713 int sock_gettstamp(struct socket *sock, void __user *userstamp, 1714 bool timeval, bool time32); 1715 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, 1716 int noblock, int *errcode); 1717 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1718 unsigned long data_len, int noblock, 1719 int *errcode, int max_page_order); 1720 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); 1721 void sock_kfree_s(struct sock *sk, void *mem, int size); 1722 void sock_kzfree_s(struct sock *sk, void *mem, int size); 1723 void sk_send_sigurg(struct sock *sk); 1724 1725 struct sockcm_cookie { 1726 u64 transmit_time; 1727 u32 mark; 1728 u16 tsflags; 1729 }; 1730 1731 static inline void sockcm_init(struct sockcm_cookie *sockc, 1732 const struct sock *sk) 1733 { 1734 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags }; 1735 } 1736 1737 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg, 1738 struct sockcm_cookie *sockc); 1739 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1740 struct sockcm_cookie *sockc); 1741 1742 /* 1743 * Functions to fill in entries in struct proto_ops when a protocol 1744 * does not implement a particular function. 1745 */ 1746 int sock_no_bind(struct socket *, struct sockaddr *, int); 1747 int sock_no_connect(struct socket *, struct sockaddr *, int, int); 1748 int sock_no_socketpair(struct socket *, struct socket *); 1749 int sock_no_accept(struct socket *, struct socket *, int, bool); 1750 int sock_no_getname(struct socket *, struct sockaddr *, int); 1751 int sock_no_ioctl(struct socket *, unsigned int, unsigned long); 1752 int sock_no_listen(struct socket *, int); 1753 int sock_no_shutdown(struct socket *, int); 1754 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t); 1755 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len); 1756 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int); 1757 int sock_no_mmap(struct file *file, struct socket *sock, 1758 struct vm_area_struct *vma); 1759 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, 1760 size_t size, int flags); 1761 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page, 1762 int offset, size_t size, int flags); 1763 1764 /* 1765 * Functions to fill in entries in struct proto_ops when a protocol 1766 * uses the inet style. 1767 */ 1768 int sock_common_getsockopt(struct socket *sock, int level, int optname, 1769 char __user *optval, int __user *optlen); 1770 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1771 int flags); 1772 int sock_common_setsockopt(struct socket *sock, int level, int optname, 1773 sockptr_t optval, unsigned int optlen); 1774 1775 void sk_common_release(struct sock *sk); 1776 1777 /* 1778 * Default socket callbacks and setup code 1779 */ 1780 1781 /* Initialise core socket variables */ 1782 void sock_init_data(struct socket *sock, struct sock *sk); 1783 1784 /* 1785 * Socket reference counting postulates. 1786 * 1787 * * Each user of socket SHOULD hold a reference count. 1788 * * Each access point to socket (an hash table bucket, reference from a list, 1789 * running timer, skb in flight MUST hold a reference count. 1790 * * When reference count hits 0, it means it will never increase back. 1791 * * When reference count hits 0, it means that no references from 1792 * outside exist to this socket and current process on current CPU 1793 * is last user and may/should destroy this socket. 1794 * * sk_free is called from any context: process, BH, IRQ. When 1795 * it is called, socket has no references from outside -> sk_free 1796 * may release descendant resources allocated by the socket, but 1797 * to the time when it is called, socket is NOT referenced by any 1798 * hash tables, lists etc. 1799 * * Packets, delivered from outside (from network or from another process) 1800 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1801 * when they sit in queue. Otherwise, packets will leak to hole, when 1802 * socket is looked up by one cpu and unhasing is made by another CPU. 1803 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1804 * (leak to backlog). Packet socket does all the processing inside 1805 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1806 * use separate SMP lock, so that they are prone too. 1807 */ 1808 1809 /* Ungrab socket and destroy it, if it was the last reference. */ 1810 static inline void sock_put(struct sock *sk) 1811 { 1812 if (refcount_dec_and_test(&sk->sk_refcnt)) 1813 sk_free(sk); 1814 } 1815 /* Generic version of sock_put(), dealing with all sockets 1816 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...) 1817 */ 1818 void sock_gen_put(struct sock *sk); 1819 1820 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested, 1821 unsigned int trim_cap, bool refcounted); 1822 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1823 const int nested) 1824 { 1825 return __sk_receive_skb(sk, skb, nested, 1, true); 1826 } 1827 1828 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 1829 { 1830 /* sk_tx_queue_mapping accept only upto a 16-bit value */ 1831 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) 1832 return; 1833 sk->sk_tx_queue_mapping = tx_queue; 1834 } 1835 1836 #define NO_QUEUE_MAPPING USHRT_MAX 1837 1838 static inline void sk_tx_queue_clear(struct sock *sk) 1839 { 1840 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING; 1841 } 1842 1843 static inline int sk_tx_queue_get(const struct sock *sk) 1844 { 1845 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING) 1846 return sk->sk_tx_queue_mapping; 1847 1848 return -1; 1849 } 1850 1851 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) 1852 { 1853 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 1854 if (skb_rx_queue_recorded(skb)) { 1855 u16 rx_queue = skb_get_rx_queue(skb); 1856 1857 if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING)) 1858 return; 1859 1860 sk->sk_rx_queue_mapping = rx_queue; 1861 } 1862 #endif 1863 } 1864 1865 static inline void sk_rx_queue_clear(struct sock *sk) 1866 { 1867 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 1868 sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING; 1869 #endif 1870 } 1871 1872 static inline int sk_rx_queue_get(const struct sock *sk) 1873 { 1874 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 1875 if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING) 1876 return sk->sk_rx_queue_mapping; 1877 #endif 1878 1879 return -1; 1880 } 1881 1882 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 1883 { 1884 sk->sk_socket = sock; 1885 } 1886 1887 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 1888 { 1889 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 1890 return &rcu_dereference_raw(sk->sk_wq)->wait; 1891 } 1892 /* Detach socket from process context. 1893 * Announce socket dead, detach it from wait queue and inode. 1894 * Note that parent inode held reference count on this struct sock, 1895 * we do not release it in this function, because protocol 1896 * probably wants some additional cleanups or even continuing 1897 * to work with this socket (TCP). 1898 */ 1899 static inline void sock_orphan(struct sock *sk) 1900 { 1901 write_lock_bh(&sk->sk_callback_lock); 1902 sock_set_flag(sk, SOCK_DEAD); 1903 sk_set_socket(sk, NULL); 1904 sk->sk_wq = NULL; 1905 write_unlock_bh(&sk->sk_callback_lock); 1906 } 1907 1908 static inline void sock_graft(struct sock *sk, struct socket *parent) 1909 { 1910 WARN_ON(parent->sk); 1911 write_lock_bh(&sk->sk_callback_lock); 1912 rcu_assign_pointer(sk->sk_wq, &parent->wq); 1913 parent->sk = sk; 1914 sk_set_socket(sk, parent); 1915 sk->sk_uid = SOCK_INODE(parent)->i_uid; 1916 security_sock_graft(sk, parent); 1917 write_unlock_bh(&sk->sk_callback_lock); 1918 } 1919 1920 kuid_t sock_i_uid(struct sock *sk); 1921 unsigned long sock_i_ino(struct sock *sk); 1922 1923 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk) 1924 { 1925 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0); 1926 } 1927 1928 static inline u32 net_tx_rndhash(void) 1929 { 1930 u32 v = prandom_u32(); 1931 1932 return v ?: 1; 1933 } 1934 1935 static inline void sk_set_txhash(struct sock *sk) 1936 { 1937 sk->sk_txhash = net_tx_rndhash(); 1938 } 1939 1940 static inline bool sk_rethink_txhash(struct sock *sk) 1941 { 1942 if (sk->sk_txhash) { 1943 sk_set_txhash(sk); 1944 return true; 1945 } 1946 return false; 1947 } 1948 1949 static inline struct dst_entry * 1950 __sk_dst_get(struct sock *sk) 1951 { 1952 return rcu_dereference_check(sk->sk_dst_cache, 1953 lockdep_sock_is_held(sk)); 1954 } 1955 1956 static inline struct dst_entry * 1957 sk_dst_get(struct sock *sk) 1958 { 1959 struct dst_entry *dst; 1960 1961 rcu_read_lock(); 1962 dst = rcu_dereference(sk->sk_dst_cache); 1963 if (dst && !atomic_inc_not_zero(&dst->__refcnt)) 1964 dst = NULL; 1965 rcu_read_unlock(); 1966 return dst; 1967 } 1968 1969 static inline void __dst_negative_advice(struct sock *sk) 1970 { 1971 struct dst_entry *ndst, *dst = __sk_dst_get(sk); 1972 1973 if (dst && dst->ops->negative_advice) { 1974 ndst = dst->ops->negative_advice(dst); 1975 1976 if (ndst != dst) { 1977 rcu_assign_pointer(sk->sk_dst_cache, ndst); 1978 sk_tx_queue_clear(sk); 1979 sk->sk_dst_pending_confirm = 0; 1980 } 1981 } 1982 } 1983 1984 static inline void dst_negative_advice(struct sock *sk) 1985 { 1986 sk_rethink_txhash(sk); 1987 __dst_negative_advice(sk); 1988 } 1989 1990 static inline void 1991 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 1992 { 1993 struct dst_entry *old_dst; 1994 1995 sk_tx_queue_clear(sk); 1996 sk->sk_dst_pending_confirm = 0; 1997 old_dst = rcu_dereference_protected(sk->sk_dst_cache, 1998 lockdep_sock_is_held(sk)); 1999 rcu_assign_pointer(sk->sk_dst_cache, dst); 2000 dst_release(old_dst); 2001 } 2002 2003 static inline void 2004 sk_dst_set(struct sock *sk, struct dst_entry *dst) 2005 { 2006 struct dst_entry *old_dst; 2007 2008 sk_tx_queue_clear(sk); 2009 sk->sk_dst_pending_confirm = 0; 2010 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst); 2011 dst_release(old_dst); 2012 } 2013 2014 static inline void 2015 __sk_dst_reset(struct sock *sk) 2016 { 2017 __sk_dst_set(sk, NULL); 2018 } 2019 2020 static inline void 2021 sk_dst_reset(struct sock *sk) 2022 { 2023 sk_dst_set(sk, NULL); 2024 } 2025 2026 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 2027 2028 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 2029 2030 static inline void sk_dst_confirm(struct sock *sk) 2031 { 2032 if (!READ_ONCE(sk->sk_dst_pending_confirm)) 2033 WRITE_ONCE(sk->sk_dst_pending_confirm, 1); 2034 } 2035 2036 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n) 2037 { 2038 if (skb_get_dst_pending_confirm(skb)) { 2039 struct sock *sk = skb->sk; 2040 unsigned long now = jiffies; 2041 2042 /* avoid dirtying neighbour */ 2043 if (READ_ONCE(n->confirmed) != now) 2044 WRITE_ONCE(n->confirmed, now); 2045 if (sk && READ_ONCE(sk->sk_dst_pending_confirm)) 2046 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 2047 } 2048 } 2049 2050 bool sk_mc_loop(struct sock *sk); 2051 2052 static inline bool sk_can_gso(const struct sock *sk) 2053 { 2054 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 2055 } 2056 2057 void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 2058 2059 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags) 2060 { 2061 sk->sk_route_nocaps |= flags; 2062 sk->sk_route_caps &= ~flags; 2063 } 2064 2065 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 2066 struct iov_iter *from, char *to, 2067 int copy, int offset) 2068 { 2069 if (skb->ip_summed == CHECKSUM_NONE) { 2070 __wsum csum = 0; 2071 if (!csum_and_copy_from_iter_full(to, copy, &csum, from)) 2072 return -EFAULT; 2073 skb->csum = csum_block_add(skb->csum, csum, offset); 2074 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 2075 if (!copy_from_iter_full_nocache(to, copy, from)) 2076 return -EFAULT; 2077 } else if (!copy_from_iter_full(to, copy, from)) 2078 return -EFAULT; 2079 2080 return 0; 2081 } 2082 2083 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 2084 struct iov_iter *from, int copy) 2085 { 2086 int err, offset = skb->len; 2087 2088 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 2089 copy, offset); 2090 if (err) 2091 __skb_trim(skb, offset); 2092 2093 return err; 2094 } 2095 2096 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from, 2097 struct sk_buff *skb, 2098 struct page *page, 2099 int off, int copy) 2100 { 2101 int err; 2102 2103 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 2104 copy, skb->len); 2105 if (err) 2106 return err; 2107 2108 skb->len += copy; 2109 skb->data_len += copy; 2110 skb->truesize += copy; 2111 sk_wmem_queued_add(sk, copy); 2112 sk_mem_charge(sk, copy); 2113 return 0; 2114 } 2115 2116 /** 2117 * sk_wmem_alloc_get - returns write allocations 2118 * @sk: socket 2119 * 2120 * Return: sk_wmem_alloc minus initial offset of one 2121 */ 2122 static inline int sk_wmem_alloc_get(const struct sock *sk) 2123 { 2124 return refcount_read(&sk->sk_wmem_alloc) - 1; 2125 } 2126 2127 /** 2128 * sk_rmem_alloc_get - returns read allocations 2129 * @sk: socket 2130 * 2131 * Return: sk_rmem_alloc 2132 */ 2133 static inline int sk_rmem_alloc_get(const struct sock *sk) 2134 { 2135 return atomic_read(&sk->sk_rmem_alloc); 2136 } 2137 2138 /** 2139 * sk_has_allocations - check if allocations are outstanding 2140 * @sk: socket 2141 * 2142 * Return: true if socket has write or read allocations 2143 */ 2144 static inline bool sk_has_allocations(const struct sock *sk) 2145 { 2146 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 2147 } 2148 2149 /** 2150 * skwq_has_sleeper - check if there are any waiting processes 2151 * @wq: struct socket_wq 2152 * 2153 * Return: true if socket_wq has waiting processes 2154 * 2155 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory 2156 * barrier call. They were added due to the race found within the tcp code. 2157 * 2158 * Consider following tcp code paths:: 2159 * 2160 * CPU1 CPU2 2161 * sys_select receive packet 2162 * ... ... 2163 * __add_wait_queue update tp->rcv_nxt 2164 * ... ... 2165 * tp->rcv_nxt check sock_def_readable 2166 * ... { 2167 * schedule rcu_read_lock(); 2168 * wq = rcu_dereference(sk->sk_wq); 2169 * if (wq && waitqueue_active(&wq->wait)) 2170 * wake_up_interruptible(&wq->wait) 2171 * ... 2172 * } 2173 * 2174 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 2175 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 2176 * could then endup calling schedule and sleep forever if there are no more 2177 * data on the socket. 2178 * 2179 */ 2180 static inline bool skwq_has_sleeper(struct socket_wq *wq) 2181 { 2182 return wq && wq_has_sleeper(&wq->wait); 2183 } 2184 2185 /** 2186 * sock_poll_wait - place memory barrier behind the poll_wait call. 2187 * @filp: file 2188 * @sock: socket to wait on 2189 * @p: poll_table 2190 * 2191 * See the comments in the wq_has_sleeper function. 2192 */ 2193 static inline void sock_poll_wait(struct file *filp, struct socket *sock, 2194 poll_table *p) 2195 { 2196 if (!poll_does_not_wait(p)) { 2197 poll_wait(filp, &sock->wq.wait, p); 2198 /* We need to be sure we are in sync with the 2199 * socket flags modification. 2200 * 2201 * This memory barrier is paired in the wq_has_sleeper. 2202 */ 2203 smp_mb(); 2204 } 2205 } 2206 2207 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk) 2208 { 2209 if (sk->sk_txhash) { 2210 skb->l4_hash = 1; 2211 skb->hash = sk->sk_txhash; 2212 } 2213 } 2214 2215 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk); 2216 2217 /* 2218 * Queue a received datagram if it will fit. Stream and sequenced 2219 * protocols can't normally use this as they need to fit buffers in 2220 * and play with them. 2221 * 2222 * Inlined as it's very short and called for pretty much every 2223 * packet ever received. 2224 */ 2225 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 2226 { 2227 skb_orphan(skb); 2228 skb->sk = sk; 2229 skb->destructor = sock_rfree; 2230 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 2231 sk_mem_charge(sk, skb->truesize); 2232 } 2233 2234 static inline void skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk) 2235 { 2236 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) { 2237 skb_orphan(skb); 2238 skb->destructor = sock_efree; 2239 skb->sk = sk; 2240 } 2241 } 2242 2243 void sk_reset_timer(struct sock *sk, struct timer_list *timer, 2244 unsigned long expires); 2245 2246 void sk_stop_timer(struct sock *sk, struct timer_list *timer); 2247 2248 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer); 2249 2250 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, 2251 struct sk_buff *skb, unsigned int flags, 2252 void (*destructor)(struct sock *sk, 2253 struct sk_buff *skb)); 2254 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2255 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2256 2257 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 2258 struct sk_buff *sock_dequeue_err_skb(struct sock *sk); 2259 2260 /* 2261 * Recover an error report and clear atomically 2262 */ 2263 2264 static inline int sock_error(struct sock *sk) 2265 { 2266 int err; 2267 if (likely(!sk->sk_err)) 2268 return 0; 2269 err = xchg(&sk->sk_err, 0); 2270 return -err; 2271 } 2272 2273 static inline unsigned long sock_wspace(struct sock *sk) 2274 { 2275 int amt = 0; 2276 2277 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 2278 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc); 2279 if (amt < 0) 2280 amt = 0; 2281 } 2282 return amt; 2283 } 2284 2285 /* Note: 2286 * We use sk->sk_wq_raw, from contexts knowing this 2287 * pointer is not NULL and cannot disappear/change. 2288 */ 2289 static inline void sk_set_bit(int nr, struct sock *sk) 2290 { 2291 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2292 !sock_flag(sk, SOCK_FASYNC)) 2293 return; 2294 2295 set_bit(nr, &sk->sk_wq_raw->flags); 2296 } 2297 2298 static inline void sk_clear_bit(int nr, struct sock *sk) 2299 { 2300 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2301 !sock_flag(sk, SOCK_FASYNC)) 2302 return; 2303 2304 clear_bit(nr, &sk->sk_wq_raw->flags); 2305 } 2306 2307 static inline void sk_wake_async(const struct sock *sk, int how, int band) 2308 { 2309 if (sock_flag(sk, SOCK_FASYNC)) { 2310 rcu_read_lock(); 2311 sock_wake_async(rcu_dereference(sk->sk_wq), how, band); 2312 rcu_read_unlock(); 2313 } 2314 } 2315 2316 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might 2317 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak. 2318 * Note: for send buffers, TCP works better if we can build two skbs at 2319 * minimum. 2320 */ 2321 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) 2322 2323 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2) 2324 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE 2325 2326 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2327 { 2328 u32 val; 2329 2330 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 2331 return; 2332 2333 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2334 2335 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF)); 2336 } 2337 2338 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp, 2339 bool force_schedule); 2340 2341 /** 2342 * sk_page_frag - return an appropriate page_frag 2343 * @sk: socket 2344 * 2345 * Use the per task page_frag instead of the per socket one for 2346 * optimization when we know that we're in the normal context and owns 2347 * everything that's associated with %current. 2348 * 2349 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest 2350 * inside other socket operations and end up recursing into sk_page_frag() 2351 * while it's already in use. 2352 * 2353 * Return: a per task page_frag if context allows that, 2354 * otherwise a per socket one. 2355 */ 2356 static inline struct page_frag *sk_page_frag(struct sock *sk) 2357 { 2358 if (gfpflags_normal_context(sk->sk_allocation)) 2359 return ¤t->task_frag; 2360 2361 return &sk->sk_frag; 2362 } 2363 2364 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); 2365 2366 /* 2367 * Default write policy as shown to user space via poll/select/SIGIO 2368 */ 2369 static inline bool sock_writeable(const struct sock *sk) 2370 { 2371 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1); 2372 } 2373 2374 static inline gfp_t gfp_any(void) 2375 { 2376 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2377 } 2378 2379 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2380 { 2381 return noblock ? 0 : sk->sk_rcvtimeo; 2382 } 2383 2384 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2385 { 2386 return noblock ? 0 : sk->sk_sndtimeo; 2387 } 2388 2389 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2390 { 2391 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len); 2392 2393 return v ?: 1; 2394 } 2395 2396 /* Alas, with timeout socket operations are not restartable. 2397 * Compare this to poll(). 2398 */ 2399 static inline int sock_intr_errno(long timeo) 2400 { 2401 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2402 } 2403 2404 struct sock_skb_cb { 2405 u32 dropcount; 2406 }; 2407 2408 /* Store sock_skb_cb at the end of skb->cb[] so protocol families 2409 * using skb->cb[] would keep using it directly and utilize its 2410 * alignement guarantee. 2411 */ 2412 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \ 2413 sizeof(struct sock_skb_cb))) 2414 2415 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \ 2416 SOCK_SKB_CB_OFFSET)) 2417 2418 #define sock_skb_cb_check_size(size) \ 2419 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET) 2420 2421 static inline void 2422 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) 2423 { 2424 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? 2425 atomic_read(&sk->sk_drops) : 0; 2426 } 2427 2428 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) 2429 { 2430 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); 2431 2432 atomic_add(segs, &sk->sk_drops); 2433 } 2434 2435 static inline ktime_t sock_read_timestamp(struct sock *sk) 2436 { 2437 #if BITS_PER_LONG==32 2438 unsigned int seq; 2439 ktime_t kt; 2440 2441 do { 2442 seq = read_seqbegin(&sk->sk_stamp_seq); 2443 kt = sk->sk_stamp; 2444 } while (read_seqretry(&sk->sk_stamp_seq, seq)); 2445 2446 return kt; 2447 #else 2448 return READ_ONCE(sk->sk_stamp); 2449 #endif 2450 } 2451 2452 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt) 2453 { 2454 #if BITS_PER_LONG==32 2455 write_seqlock(&sk->sk_stamp_seq); 2456 sk->sk_stamp = kt; 2457 write_sequnlock(&sk->sk_stamp_seq); 2458 #else 2459 WRITE_ONCE(sk->sk_stamp, kt); 2460 #endif 2461 } 2462 2463 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2464 struct sk_buff *skb); 2465 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2466 struct sk_buff *skb); 2467 2468 static inline void 2469 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2470 { 2471 ktime_t kt = skb->tstamp; 2472 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2473 2474 /* 2475 * generate control messages if 2476 * - receive time stamping in software requested 2477 * - software time stamp available and wanted 2478 * - hardware time stamps available and wanted 2479 */ 2480 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2481 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) || 2482 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) || 2483 (hwtstamps->hwtstamp && 2484 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))) 2485 __sock_recv_timestamp(msg, sk, skb); 2486 else 2487 sock_write_timestamp(sk, kt); 2488 2489 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid) 2490 __sock_recv_wifi_status(msg, sk, skb); 2491 } 2492 2493 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2494 struct sk_buff *skb); 2495 2496 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC) 2497 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk, 2498 struct sk_buff *skb) 2499 { 2500 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \ 2501 (1UL << SOCK_RCVTSTAMP)) 2502 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \ 2503 SOF_TIMESTAMPING_RAW_HARDWARE) 2504 2505 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY) 2506 __sock_recv_ts_and_drops(msg, sk, skb); 2507 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP))) 2508 sock_write_timestamp(sk, skb->tstamp); 2509 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP)) 2510 sock_write_timestamp(sk, 0); 2511 } 2512 2513 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags); 2514 2515 /** 2516 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2517 * @sk: socket sending this packet 2518 * @tsflags: timestamping flags to use 2519 * @tx_flags: completed with instructions for time stamping 2520 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno) 2521 * 2522 * Note: callers should take care of initial ``*tx_flags`` value (usually 0) 2523 */ 2524 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2525 __u8 *tx_flags, __u32 *tskey) 2526 { 2527 if (unlikely(tsflags)) { 2528 __sock_tx_timestamp(tsflags, tx_flags); 2529 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey && 2530 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) 2531 *tskey = sk->sk_tskey++; 2532 } 2533 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS))) 2534 *tx_flags |= SKBTX_WIFI_STATUS; 2535 } 2536 2537 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2538 __u8 *tx_flags) 2539 { 2540 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL); 2541 } 2542 2543 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) 2544 { 2545 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags, 2546 &skb_shinfo(skb)->tskey); 2547 } 2548 2549 DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key); 2550 /** 2551 * sk_eat_skb - Release a skb if it is no longer needed 2552 * @sk: socket to eat this skb from 2553 * @skb: socket buffer to eat 2554 * 2555 * This routine must be called with interrupts disabled or with the socket 2556 * locked so that the sk_buff queue operation is ok. 2557 */ 2558 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) 2559 { 2560 __skb_unlink(skb, &sk->sk_receive_queue); 2561 if (static_branch_unlikely(&tcp_rx_skb_cache_key) && 2562 !sk->sk_rx_skb_cache) { 2563 sk->sk_rx_skb_cache = skb; 2564 skb_orphan(skb); 2565 return; 2566 } 2567 __kfree_skb(skb); 2568 } 2569 2570 static inline 2571 struct net *sock_net(const struct sock *sk) 2572 { 2573 return read_pnet(&sk->sk_net); 2574 } 2575 2576 static inline 2577 void sock_net_set(struct sock *sk, struct net *net) 2578 { 2579 write_pnet(&sk->sk_net, net); 2580 } 2581 2582 static inline bool 2583 skb_sk_is_prefetched(struct sk_buff *skb) 2584 { 2585 #ifdef CONFIG_INET 2586 return skb->destructor == sock_pfree; 2587 #else 2588 return false; 2589 #endif /* CONFIG_INET */ 2590 } 2591 2592 /* This helper checks if a socket is a full socket, 2593 * ie _not_ a timewait or request socket. 2594 */ 2595 static inline bool sk_fullsock(const struct sock *sk) 2596 { 2597 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV); 2598 } 2599 2600 static inline bool 2601 sk_is_refcounted(struct sock *sk) 2602 { 2603 /* Only full sockets have sk->sk_flags. */ 2604 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE); 2605 } 2606 2607 /** 2608 * skb_steal_sock - steal a socket from an sk_buff 2609 * @skb: sk_buff to steal the socket from 2610 * @refcounted: is set to true if the socket is reference-counted 2611 */ 2612 static inline struct sock * 2613 skb_steal_sock(struct sk_buff *skb, bool *refcounted) 2614 { 2615 if (skb->sk) { 2616 struct sock *sk = skb->sk; 2617 2618 *refcounted = true; 2619 if (skb_sk_is_prefetched(skb)) 2620 *refcounted = sk_is_refcounted(sk); 2621 skb->destructor = NULL; 2622 skb->sk = NULL; 2623 return sk; 2624 } 2625 *refcounted = false; 2626 return NULL; 2627 } 2628 2629 /* Checks if this SKB belongs to an HW offloaded socket 2630 * and whether any SW fallbacks are required based on dev. 2631 * Check decrypted mark in case skb_orphan() cleared socket. 2632 */ 2633 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, 2634 struct net_device *dev) 2635 { 2636 #ifdef CONFIG_SOCK_VALIDATE_XMIT 2637 struct sock *sk = skb->sk; 2638 2639 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) { 2640 skb = sk->sk_validate_xmit_skb(sk, dev, skb); 2641 #ifdef CONFIG_TLS_DEVICE 2642 } else if (unlikely(skb->decrypted)) { 2643 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n"); 2644 kfree_skb(skb); 2645 skb = NULL; 2646 #endif 2647 } 2648 #endif 2649 2650 return skb; 2651 } 2652 2653 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV 2654 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE) 2655 */ 2656 static inline bool sk_listener(const struct sock *sk) 2657 { 2658 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV); 2659 } 2660 2661 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag); 2662 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level, 2663 int type); 2664 2665 bool sk_ns_capable(const struct sock *sk, 2666 struct user_namespace *user_ns, int cap); 2667 bool sk_capable(const struct sock *sk, int cap); 2668 bool sk_net_capable(const struct sock *sk, int cap); 2669 2670 void sk_get_meminfo(const struct sock *sk, u32 *meminfo); 2671 2672 /* Take into consideration the size of the struct sk_buff overhead in the 2673 * determination of these values, since that is non-constant across 2674 * platforms. This makes socket queueing behavior and performance 2675 * not depend upon such differences. 2676 */ 2677 #define _SK_MEM_PACKETS 256 2678 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 2679 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2680 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2681 2682 extern __u32 sysctl_wmem_max; 2683 extern __u32 sysctl_rmem_max; 2684 2685 extern int sysctl_tstamp_allow_data; 2686 extern int sysctl_optmem_max; 2687 2688 extern __u32 sysctl_wmem_default; 2689 extern __u32 sysctl_rmem_default; 2690 2691 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2692 2693 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) 2694 { 2695 /* Does this proto have per netns sysctl_wmem ? */ 2696 if (proto->sysctl_wmem_offset) 2697 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset); 2698 2699 return *proto->sysctl_wmem; 2700 } 2701 2702 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) 2703 { 2704 /* Does this proto have per netns sysctl_rmem ? */ 2705 if (proto->sysctl_rmem_offset) 2706 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset); 2707 2708 return *proto->sysctl_rmem; 2709 } 2710 2711 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) 2712 * Some wifi drivers need to tweak it to get more chunks. 2713 * They can use this helper from their ndo_start_xmit() 2714 */ 2715 static inline void sk_pacing_shift_update(struct sock *sk, int val) 2716 { 2717 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val) 2718 return; 2719 WRITE_ONCE(sk->sk_pacing_shift, val); 2720 } 2721 2722 /* if a socket is bound to a device, check that the given device 2723 * index is either the same or that the socket is bound to an L3 2724 * master device and the given device index is also enslaved to 2725 * that L3 master 2726 */ 2727 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif) 2728 { 2729 int mdif; 2730 2731 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif) 2732 return true; 2733 2734 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif); 2735 if (mdif && mdif == sk->sk_bound_dev_if) 2736 return true; 2737 2738 return false; 2739 } 2740 2741 void sock_def_readable(struct sock *sk); 2742 2743 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk); 2744 void sock_enable_timestamps(struct sock *sk); 2745 void sock_no_linger(struct sock *sk); 2746 void sock_set_keepalive(struct sock *sk); 2747 void sock_set_priority(struct sock *sk, u32 priority); 2748 void sock_set_rcvbuf(struct sock *sk, int val); 2749 void sock_set_mark(struct sock *sk, u32 val); 2750 void sock_set_reuseaddr(struct sock *sk); 2751 void sock_set_reuseport(struct sock *sk); 2752 void sock_set_sndtimeo(struct sock *sk, s64 secs); 2753 2754 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len); 2755 2756 #endif /* _SOCK_H */ 2757