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/rculist_nulls.h> 60 #include <linux/poll.h> 61 #include <linux/sockptr.h> 62 #include <linux/indirect_call_wrapper.h> 63 #include <linux/atomic.h> 64 #include <linux/refcount.h> 65 #include <linux/llist.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 #include <uapi/linux/socket.h> 72 73 /* 74 * This structure really needs to be cleaned up. 75 * Most of it is for TCP, and not used by any of 76 * the other protocols. 77 */ 78 79 /* Define this to get the SOCK_DBG debugging facility. */ 80 #define SOCK_DEBUGGING 81 #ifdef SOCK_DEBUGGING 82 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \ 83 printk(KERN_DEBUG msg); } while (0) 84 #else 85 /* Validate arguments and do nothing */ 86 static inline __printf(2, 3) 87 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...) 88 { 89 } 90 #endif 91 92 /* This is the per-socket lock. The spinlock provides a synchronization 93 * between user contexts and software interrupt processing, whereas the 94 * mini-semaphore synchronizes multiple users amongst themselves. 95 */ 96 typedef struct { 97 spinlock_t slock; 98 int owned; 99 wait_queue_head_t wq; 100 /* 101 * We express the mutex-alike socket_lock semantics 102 * to the lock validator by explicitly managing 103 * the slock as a lock variant (in addition to 104 * the slock itself): 105 */ 106 #ifdef CONFIG_DEBUG_LOCK_ALLOC 107 struct lockdep_map dep_map; 108 #endif 109 } socket_lock_t; 110 111 struct sock; 112 struct proto; 113 struct net; 114 115 typedef __u32 __bitwise __portpair; 116 typedef __u64 __bitwise __addrpair; 117 118 /** 119 * struct sock_common - minimal network layer representation of sockets 120 * @skc_daddr: Foreign IPv4 addr 121 * @skc_rcv_saddr: Bound local IPv4 addr 122 * @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr 123 * @skc_hash: hash value used with various protocol lookup tables 124 * @skc_u16hashes: two u16 hash values used by UDP lookup tables 125 * @skc_dport: placeholder for inet_dport/tw_dport 126 * @skc_num: placeholder for inet_num/tw_num 127 * @skc_portpair: __u32 union of @skc_dport & @skc_num 128 * @skc_family: network address family 129 * @skc_state: Connection state 130 * @skc_reuse: %SO_REUSEADDR setting 131 * @skc_reuseport: %SO_REUSEPORT setting 132 * @skc_ipv6only: socket is IPV6 only 133 * @skc_net_refcnt: socket is using net ref counting 134 * @skc_bound_dev_if: bound device index if != 0 135 * @skc_bind_node: bind hash linkage for various protocol lookup tables 136 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol 137 * @skc_prot: protocol handlers inside a network family 138 * @skc_net: reference to the network namespace of this socket 139 * @skc_v6_daddr: IPV6 destination address 140 * @skc_v6_rcv_saddr: IPV6 source address 141 * @skc_cookie: socket's cookie value 142 * @skc_node: main hash linkage for various protocol lookup tables 143 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol 144 * @skc_tx_queue_mapping: tx queue number for this connection 145 * @skc_rx_queue_mapping: rx queue number for this connection 146 * @skc_flags: place holder for sk_flags 147 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE, 148 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings 149 * @skc_listener: connection request listener socket (aka rsk_listener) 150 * [union with @skc_flags] 151 * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row 152 * [union with @skc_flags] 153 * @skc_incoming_cpu: record/match cpu processing incoming packets 154 * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled) 155 * [union with @skc_incoming_cpu] 156 * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number 157 * [union with @skc_incoming_cpu] 158 * @skc_refcnt: reference count 159 * 160 * This is the minimal network layer representation of sockets, the header 161 * for struct sock and struct inet_timewait_sock. 162 */ 163 struct sock_common { 164 union { 165 __addrpair skc_addrpair; 166 struct { 167 __be32 skc_daddr; 168 __be32 skc_rcv_saddr; 169 }; 170 }; 171 union { 172 unsigned int skc_hash; 173 __u16 skc_u16hashes[2]; 174 }; 175 /* skc_dport && skc_num must be grouped as well */ 176 union { 177 __portpair skc_portpair; 178 struct { 179 __be16 skc_dport; 180 __u16 skc_num; 181 }; 182 }; 183 184 unsigned short skc_family; 185 volatile unsigned char skc_state; 186 unsigned char skc_reuse:4; 187 unsigned char skc_reuseport:1; 188 unsigned char skc_ipv6only:1; 189 unsigned char skc_net_refcnt:1; 190 int skc_bound_dev_if; 191 union { 192 struct hlist_node skc_bind_node; 193 struct hlist_node skc_portaddr_node; 194 }; 195 struct proto *skc_prot; 196 possible_net_t skc_net; 197 198 #if IS_ENABLED(CONFIG_IPV6) 199 struct in6_addr skc_v6_daddr; 200 struct in6_addr skc_v6_rcv_saddr; 201 #endif 202 203 atomic64_t skc_cookie; 204 205 /* following fields are padding to force 206 * offset(struct sock, sk_refcnt) == 128 on 64bit arches 207 * assuming IPV6 is enabled. We use this padding differently 208 * for different kind of 'sockets' 209 */ 210 union { 211 unsigned long skc_flags; 212 struct sock *skc_listener; /* request_sock */ 213 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */ 214 }; 215 /* 216 * fields between dontcopy_begin/dontcopy_end 217 * are not copied in sock_copy() 218 */ 219 /* private: */ 220 int skc_dontcopy_begin[0]; 221 /* public: */ 222 union { 223 struct hlist_node skc_node; 224 struct hlist_nulls_node skc_nulls_node; 225 }; 226 unsigned short skc_tx_queue_mapping; 227 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 228 unsigned short skc_rx_queue_mapping; 229 #endif 230 union { 231 int skc_incoming_cpu; 232 u32 skc_rcv_wnd; 233 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */ 234 }; 235 236 refcount_t skc_refcnt; 237 /* private: */ 238 int skc_dontcopy_end[0]; 239 union { 240 u32 skc_rxhash; 241 u32 skc_window_clamp; 242 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */ 243 }; 244 /* public: */ 245 }; 246 247 struct bpf_local_storage; 248 struct sk_filter; 249 250 /** 251 * struct sock - network layer representation of sockets 252 * @__sk_common: shared layout with inet_timewait_sock 253 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN 254 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings 255 * @sk_lock: synchronizer 256 * @sk_kern_sock: True if sock is using kernel lock classes 257 * @sk_rcvbuf: size of receive buffer in bytes 258 * @sk_wq: sock wait queue and async head 259 * @sk_rx_dst: receive input route used by early demux 260 * @sk_rx_dst_ifindex: ifindex for @sk_rx_dst 261 * @sk_rx_dst_cookie: cookie for @sk_rx_dst 262 * @sk_dst_cache: destination cache 263 * @sk_dst_pending_confirm: need to confirm neighbour 264 * @sk_policy: flow policy 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_reserved_mem: space reserved and non-reclaimable for the socket 273 * @sk_napi_id: id of the last napi context to receive data for sk 274 * @sk_ll_usec: usecs to busypoll when there is no data 275 * @sk_allocation: allocation mode 276 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler) 277 * @sk_pacing_status: Pacing status (requested, handled by sch_fq) 278 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE) 279 * @sk_sndbuf: size of send buffer in bytes 280 * @__sk_flags_offset: empty field used to determine location of bitfield 281 * @sk_padding: unused element for alignment 282 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets 283 * @sk_no_check_rx: allow zero checksum in RX packets 284 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO) 285 * @sk_gso_disabled: if set, NETIF_F_GSO_MASK is forbidden. 286 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4) 287 * @sk_gso_max_size: Maximum GSO segment size to build 288 * @sk_gso_max_segs: Maximum number of GSO segments 289 * @sk_pacing_shift: scaling factor for TCP Small Queues 290 * @sk_lingertime: %SO_LINGER l_linger setting 291 * @sk_backlog: always used with the per-socket spinlock held 292 * @sk_callback_lock: used with the callbacks in the end of this struct 293 * @sk_error_queue: rarely used 294 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt, 295 * IPV6_ADDRFORM for instance) 296 * @sk_err: last error 297 * @sk_err_soft: errors that don't cause failure but are the cause of a 298 * persistent failure not just 'timed out' 299 * @sk_drops: raw/udp drops counter 300 * @sk_ack_backlog: current listen backlog 301 * @sk_max_ack_backlog: listen backlog set in listen() 302 * @sk_uid: user id of owner 303 * @sk_prefer_busy_poll: prefer busypolling over softirq processing 304 * @sk_busy_poll_budget: napi processing budget when busypolling 305 * @sk_priority: %SO_PRIORITY setting 306 * @sk_type: socket type (%SOCK_STREAM, etc) 307 * @sk_protocol: which protocol this socket belongs in this network family 308 * @sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred 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_txrehash: enable TX hash rethink 316 * @sk_filter: socket filtering instructions 317 * @sk_timer: sock cleanup timer 318 * @sk_stamp: time stamp of last packet received 319 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only 320 * @sk_tsflags: SO_TIMESTAMPING flags 321 * @sk_use_task_frag: allow sk_page_frag() to use current->task_frag. 322 * Sockets that can be used under memory reclaim should 323 * set this to false. 324 * @sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock 325 * for timestamping 326 * @sk_tskey: counter to disambiguate concurrent tstamp requests 327 * @sk_zckey: counter to order MSG_ZEROCOPY notifications 328 * @sk_socket: Identd and reporting IO signals 329 * @sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock. 330 * @sk_frag: cached page frag 331 * @sk_peek_off: current peek_offset value 332 * @sk_send_head: front of stuff to transmit 333 * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head] 334 * @sk_security: used by security modules 335 * @sk_mark: generic packet mark 336 * @sk_cgrp_data: cgroup data for this cgroup 337 * @sk_memcg: this socket's memory cgroup association 338 * @sk_write_pending: a write to stream socket waits to start 339 * @sk_disconnects: number of disconnect operations performed on this sock 340 * @sk_state_change: callback to indicate change in the state of the sock 341 * @sk_data_ready: callback to indicate there is data to be processed 342 * @sk_write_space: callback to indicate there is bf sending space available 343 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE) 344 * @sk_backlog_rcv: callback to process the backlog 345 * @sk_validate_xmit_skb: ptr to an optional validate function 346 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0 347 * @sk_reuseport_cb: reuseport group container 348 * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage 349 * @sk_rcu: used during RCU grace period 350 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME) 351 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME 352 * @sk_txtime_report_errors: set report errors mode for SO_TXTIME 353 * @sk_txtime_unused: unused txtime flags 354 * @ns_tracker: tracker for netns reference 355 * @sk_bind2_node: bind node in the bhash2 table 356 */ 357 struct sock { 358 /* 359 * Now struct inet_timewait_sock also uses sock_common, so please just 360 * don't add nothing before this first member (__sk_common) --acme 361 */ 362 struct sock_common __sk_common; 363 #define sk_node __sk_common.skc_node 364 #define sk_nulls_node __sk_common.skc_nulls_node 365 #define sk_refcnt __sk_common.skc_refcnt 366 #define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping 367 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 368 #define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping 369 #endif 370 371 #define sk_dontcopy_begin __sk_common.skc_dontcopy_begin 372 #define sk_dontcopy_end __sk_common.skc_dontcopy_end 373 #define sk_hash __sk_common.skc_hash 374 #define sk_portpair __sk_common.skc_portpair 375 #define sk_num __sk_common.skc_num 376 #define sk_dport __sk_common.skc_dport 377 #define sk_addrpair __sk_common.skc_addrpair 378 #define sk_daddr __sk_common.skc_daddr 379 #define sk_rcv_saddr __sk_common.skc_rcv_saddr 380 #define sk_family __sk_common.skc_family 381 #define sk_state __sk_common.skc_state 382 #define sk_reuse __sk_common.skc_reuse 383 #define sk_reuseport __sk_common.skc_reuseport 384 #define sk_ipv6only __sk_common.skc_ipv6only 385 #define sk_net_refcnt __sk_common.skc_net_refcnt 386 #define sk_bound_dev_if __sk_common.skc_bound_dev_if 387 #define sk_bind_node __sk_common.skc_bind_node 388 #define sk_prot __sk_common.skc_prot 389 #define sk_net __sk_common.skc_net 390 #define sk_v6_daddr __sk_common.skc_v6_daddr 391 #define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr 392 #define sk_cookie __sk_common.skc_cookie 393 #define sk_incoming_cpu __sk_common.skc_incoming_cpu 394 #define sk_flags __sk_common.skc_flags 395 #define sk_rxhash __sk_common.skc_rxhash 396 397 /* early demux fields */ 398 struct dst_entry __rcu *sk_rx_dst; 399 int sk_rx_dst_ifindex; 400 u32 sk_rx_dst_cookie; 401 402 socket_lock_t sk_lock; 403 atomic_t sk_drops; 404 int sk_rcvlowat; 405 struct sk_buff_head sk_error_queue; 406 struct sk_buff_head sk_receive_queue; 407 /* 408 * The backlog queue is special, it is always used with 409 * the per-socket spinlock held and requires low latency 410 * access. Therefore we special case it's implementation. 411 * Note : rmem_alloc is in this structure to fill a hole 412 * on 64bit arches, not because its logically part of 413 * backlog. 414 */ 415 struct { 416 atomic_t rmem_alloc; 417 int len; 418 struct sk_buff *head; 419 struct sk_buff *tail; 420 } sk_backlog; 421 422 #define sk_rmem_alloc sk_backlog.rmem_alloc 423 424 int sk_forward_alloc; 425 u32 sk_reserved_mem; 426 #ifdef CONFIG_NET_RX_BUSY_POLL 427 unsigned int sk_ll_usec; 428 /* ===== mostly read cache line ===== */ 429 unsigned int sk_napi_id; 430 #endif 431 int sk_rcvbuf; 432 int sk_disconnects; 433 434 struct sk_filter __rcu *sk_filter; 435 union { 436 struct socket_wq __rcu *sk_wq; 437 /* private: */ 438 struct socket_wq *sk_wq_raw; 439 /* public: */ 440 }; 441 #ifdef CONFIG_XFRM 442 struct xfrm_policy __rcu *sk_policy[2]; 443 #endif 444 445 struct dst_entry __rcu *sk_dst_cache; 446 atomic_t sk_omem_alloc; 447 int sk_sndbuf; 448 449 /* ===== cache line for TX ===== */ 450 int sk_wmem_queued; 451 refcount_t sk_wmem_alloc; 452 unsigned long sk_tsq_flags; 453 union { 454 struct sk_buff *sk_send_head; 455 struct rb_root tcp_rtx_queue; 456 }; 457 struct sk_buff_head sk_write_queue; 458 __s32 sk_peek_off; 459 int sk_write_pending; 460 __u32 sk_dst_pending_confirm; 461 u32 sk_pacing_status; /* see enum sk_pacing */ 462 long sk_sndtimeo; 463 struct timer_list sk_timer; 464 __u32 sk_priority; 465 __u32 sk_mark; 466 unsigned long sk_pacing_rate; /* bytes per second */ 467 unsigned long sk_max_pacing_rate; 468 struct page_frag sk_frag; 469 netdev_features_t sk_route_caps; 470 int sk_gso_type; 471 unsigned int sk_gso_max_size; 472 gfp_t sk_allocation; 473 __u32 sk_txhash; 474 475 /* 476 * Because of non atomicity rules, all 477 * changes are protected by socket lock. 478 */ 479 u8 sk_gso_disabled : 1, 480 sk_kern_sock : 1, 481 sk_no_check_tx : 1, 482 sk_no_check_rx : 1, 483 sk_userlocks : 4; 484 u8 sk_pacing_shift; 485 u16 sk_type; 486 u16 sk_protocol; 487 u16 sk_gso_max_segs; 488 unsigned long sk_lingertime; 489 struct proto *sk_prot_creator; 490 rwlock_t sk_callback_lock; 491 int sk_err, 492 sk_err_soft; 493 u32 sk_ack_backlog; 494 u32 sk_max_ack_backlog; 495 kuid_t sk_uid; 496 u8 sk_txrehash; 497 #ifdef CONFIG_NET_RX_BUSY_POLL 498 u8 sk_prefer_busy_poll; 499 u16 sk_busy_poll_budget; 500 #endif 501 spinlock_t sk_peer_lock; 502 int sk_bind_phc; 503 struct pid *sk_peer_pid; 504 const struct cred *sk_peer_cred; 505 506 long sk_rcvtimeo; 507 ktime_t sk_stamp; 508 #if BITS_PER_LONG==32 509 seqlock_t sk_stamp_seq; 510 #endif 511 atomic_t sk_tskey; 512 atomic_t sk_zckey; 513 u32 sk_tsflags; 514 u8 sk_shutdown; 515 516 u8 sk_clockid; 517 u8 sk_txtime_deadline_mode : 1, 518 sk_txtime_report_errors : 1, 519 sk_txtime_unused : 6; 520 bool sk_use_task_frag; 521 522 struct socket *sk_socket; 523 void *sk_user_data; 524 #ifdef CONFIG_SECURITY 525 void *sk_security; 526 #endif 527 struct sock_cgroup_data sk_cgrp_data; 528 struct mem_cgroup *sk_memcg; 529 void (*sk_state_change)(struct sock *sk); 530 void (*sk_data_ready)(struct sock *sk); 531 void (*sk_write_space)(struct sock *sk); 532 void (*sk_error_report)(struct sock *sk); 533 int (*sk_backlog_rcv)(struct sock *sk, 534 struct sk_buff *skb); 535 #ifdef CONFIG_SOCK_VALIDATE_XMIT 536 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk, 537 struct net_device *dev, 538 struct sk_buff *skb); 539 #endif 540 void (*sk_destruct)(struct sock *sk); 541 struct sock_reuseport __rcu *sk_reuseport_cb; 542 #ifdef CONFIG_BPF_SYSCALL 543 struct bpf_local_storage __rcu *sk_bpf_storage; 544 #endif 545 struct rcu_head sk_rcu; 546 netns_tracker ns_tracker; 547 struct hlist_node sk_bind2_node; 548 }; 549 550 enum sk_pacing { 551 SK_PACING_NONE = 0, 552 SK_PACING_NEEDED = 1, 553 SK_PACING_FQ = 2, 554 }; 555 556 /* flag bits in sk_user_data 557 * 558 * - SK_USER_DATA_NOCOPY: Pointer stored in sk_user_data might 559 * not be suitable for copying when cloning the socket. For instance, 560 * it can point to a reference counted object. sk_user_data bottom 561 * bit is set if pointer must not be copied. 562 * 563 * - SK_USER_DATA_BPF: Mark whether sk_user_data field is 564 * managed/owned by a BPF reuseport array. This bit should be set 565 * when sk_user_data's sk is added to the bpf's reuseport_array. 566 * 567 * - SK_USER_DATA_PSOCK: Mark whether pointer stored in 568 * sk_user_data points to psock type. This bit should be set 569 * when sk_user_data is assigned to a psock object. 570 */ 571 #define SK_USER_DATA_NOCOPY 1UL 572 #define SK_USER_DATA_BPF 2UL 573 #define SK_USER_DATA_PSOCK 4UL 574 #define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\ 575 SK_USER_DATA_PSOCK) 576 577 /** 578 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied 579 * @sk: socket 580 */ 581 static inline bool sk_user_data_is_nocopy(const struct sock *sk) 582 { 583 return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY); 584 } 585 586 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data))) 587 588 /** 589 * __locked_read_sk_user_data_with_flags - return the pointer 590 * only if argument flags all has been set in sk_user_data. Otherwise 591 * return NULL 592 * 593 * @sk: socket 594 * @flags: flag bits 595 * 596 * The caller must be holding sk->sk_callback_lock. 597 */ 598 static inline void * 599 __locked_read_sk_user_data_with_flags(const struct sock *sk, 600 uintptr_t flags) 601 { 602 uintptr_t sk_user_data = 603 (uintptr_t)rcu_dereference_check(__sk_user_data(sk), 604 lockdep_is_held(&sk->sk_callback_lock)); 605 606 WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK); 607 608 if ((sk_user_data & flags) == flags) 609 return (void *)(sk_user_data & SK_USER_DATA_PTRMASK); 610 return NULL; 611 } 612 613 /** 614 * __rcu_dereference_sk_user_data_with_flags - return the pointer 615 * only if argument flags all has been set in sk_user_data. Otherwise 616 * return NULL 617 * 618 * @sk: socket 619 * @flags: flag bits 620 */ 621 static inline void * 622 __rcu_dereference_sk_user_data_with_flags(const struct sock *sk, 623 uintptr_t flags) 624 { 625 uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk)); 626 627 WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK); 628 629 if ((sk_user_data & flags) == flags) 630 return (void *)(sk_user_data & SK_USER_DATA_PTRMASK); 631 return NULL; 632 } 633 634 #define rcu_dereference_sk_user_data(sk) \ 635 __rcu_dereference_sk_user_data_with_flags(sk, 0) 636 #define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags) \ 637 ({ \ 638 uintptr_t __tmp1 = (uintptr_t)(ptr), \ 639 __tmp2 = (uintptr_t)(flags); \ 640 WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK); \ 641 WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK); \ 642 rcu_assign_pointer(__sk_user_data((sk)), \ 643 __tmp1 | __tmp2); \ 644 }) 645 #define rcu_assign_sk_user_data(sk, ptr) \ 646 __rcu_assign_sk_user_data_with_flags(sk, ptr, 0) 647 648 static inline 649 struct net *sock_net(const struct sock *sk) 650 { 651 return read_pnet(&sk->sk_net); 652 } 653 654 static inline 655 void sock_net_set(struct sock *sk, struct net *net) 656 { 657 write_pnet(&sk->sk_net, net); 658 } 659 660 /* 661 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK 662 * or not whether his port will be reused by someone else. SK_FORCE_REUSE 663 * on a socket means that the socket will reuse everybody else's port 664 * without looking at the other's sk_reuse value. 665 */ 666 667 #define SK_NO_REUSE 0 668 #define SK_CAN_REUSE 1 669 #define SK_FORCE_REUSE 2 670 671 int sk_set_peek_off(struct sock *sk, int val); 672 673 static inline int sk_peek_offset(const struct sock *sk, int flags) 674 { 675 if (unlikely(flags & MSG_PEEK)) { 676 return READ_ONCE(sk->sk_peek_off); 677 } 678 679 return 0; 680 } 681 682 static inline void sk_peek_offset_bwd(struct sock *sk, int val) 683 { 684 s32 off = READ_ONCE(sk->sk_peek_off); 685 686 if (unlikely(off >= 0)) { 687 off = max_t(s32, off - val, 0); 688 WRITE_ONCE(sk->sk_peek_off, off); 689 } 690 } 691 692 static inline void sk_peek_offset_fwd(struct sock *sk, int val) 693 { 694 sk_peek_offset_bwd(sk, -val); 695 } 696 697 /* 698 * Hashed lists helper routines 699 */ 700 static inline struct sock *sk_entry(const struct hlist_node *node) 701 { 702 return hlist_entry(node, struct sock, sk_node); 703 } 704 705 static inline struct sock *__sk_head(const struct hlist_head *head) 706 { 707 return hlist_entry(head->first, struct sock, sk_node); 708 } 709 710 static inline struct sock *sk_head(const struct hlist_head *head) 711 { 712 return hlist_empty(head) ? NULL : __sk_head(head); 713 } 714 715 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head) 716 { 717 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node); 718 } 719 720 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head) 721 { 722 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head); 723 } 724 725 static inline struct sock *sk_next(const struct sock *sk) 726 { 727 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node); 728 } 729 730 static inline struct sock *sk_nulls_next(const struct sock *sk) 731 { 732 return (!is_a_nulls(sk->sk_nulls_node.next)) ? 733 hlist_nulls_entry(sk->sk_nulls_node.next, 734 struct sock, sk_nulls_node) : 735 NULL; 736 } 737 738 static inline bool sk_unhashed(const struct sock *sk) 739 { 740 return hlist_unhashed(&sk->sk_node); 741 } 742 743 static inline bool sk_hashed(const struct sock *sk) 744 { 745 return !sk_unhashed(sk); 746 } 747 748 static inline void sk_node_init(struct hlist_node *node) 749 { 750 node->pprev = NULL; 751 } 752 753 static inline void __sk_del_node(struct sock *sk) 754 { 755 __hlist_del(&sk->sk_node); 756 } 757 758 /* NB: equivalent to hlist_del_init_rcu */ 759 static inline bool __sk_del_node_init(struct sock *sk) 760 { 761 if (sk_hashed(sk)) { 762 __sk_del_node(sk); 763 sk_node_init(&sk->sk_node); 764 return true; 765 } 766 return false; 767 } 768 769 /* Grab socket reference count. This operation is valid only 770 when sk is ALREADY grabbed f.e. it is found in hash table 771 or a list and the lookup is made under lock preventing hash table 772 modifications. 773 */ 774 775 static __always_inline void sock_hold(struct sock *sk) 776 { 777 refcount_inc(&sk->sk_refcnt); 778 } 779 780 /* Ungrab socket in the context, which assumes that socket refcnt 781 cannot hit zero, f.e. it is true in context of any socketcall. 782 */ 783 static __always_inline void __sock_put(struct sock *sk) 784 { 785 refcount_dec(&sk->sk_refcnt); 786 } 787 788 static inline bool sk_del_node_init(struct sock *sk) 789 { 790 bool rc = __sk_del_node_init(sk); 791 792 if (rc) { 793 /* paranoid for a while -acme */ 794 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 795 __sock_put(sk); 796 } 797 return rc; 798 } 799 #define sk_del_node_init_rcu(sk) sk_del_node_init(sk) 800 801 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk) 802 { 803 if (sk_hashed(sk)) { 804 hlist_nulls_del_init_rcu(&sk->sk_nulls_node); 805 return true; 806 } 807 return false; 808 } 809 810 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk) 811 { 812 bool rc = __sk_nulls_del_node_init_rcu(sk); 813 814 if (rc) { 815 /* paranoid for a while -acme */ 816 WARN_ON(refcount_read(&sk->sk_refcnt) == 1); 817 __sock_put(sk); 818 } 819 return rc; 820 } 821 822 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list) 823 { 824 hlist_add_head(&sk->sk_node, list); 825 } 826 827 static inline void sk_add_node(struct sock *sk, struct hlist_head *list) 828 { 829 sock_hold(sk); 830 __sk_add_node(sk, list); 831 } 832 833 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list) 834 { 835 sock_hold(sk); 836 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport && 837 sk->sk_family == AF_INET6) 838 hlist_add_tail_rcu(&sk->sk_node, list); 839 else 840 hlist_add_head_rcu(&sk->sk_node, list); 841 } 842 843 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list) 844 { 845 sock_hold(sk); 846 hlist_add_tail_rcu(&sk->sk_node, list); 847 } 848 849 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 850 { 851 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list); 852 } 853 854 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list) 855 { 856 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list); 857 } 858 859 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list) 860 { 861 sock_hold(sk); 862 __sk_nulls_add_node_rcu(sk, list); 863 } 864 865 static inline void __sk_del_bind_node(struct sock *sk) 866 { 867 __hlist_del(&sk->sk_bind_node); 868 } 869 870 static inline void sk_add_bind_node(struct sock *sk, 871 struct hlist_head *list) 872 { 873 hlist_add_head(&sk->sk_bind_node, list); 874 } 875 876 static inline void __sk_del_bind2_node(struct sock *sk) 877 { 878 __hlist_del(&sk->sk_bind2_node); 879 } 880 881 static inline void sk_add_bind2_node(struct sock *sk, struct hlist_head *list) 882 { 883 hlist_add_head(&sk->sk_bind2_node, list); 884 } 885 886 #define sk_for_each(__sk, list) \ 887 hlist_for_each_entry(__sk, list, sk_node) 888 #define sk_for_each_rcu(__sk, list) \ 889 hlist_for_each_entry_rcu(__sk, list, sk_node) 890 #define sk_nulls_for_each(__sk, node, list) \ 891 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node) 892 #define sk_nulls_for_each_rcu(__sk, node, list) \ 893 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node) 894 #define sk_for_each_from(__sk) \ 895 hlist_for_each_entry_from(__sk, sk_node) 896 #define sk_nulls_for_each_from(__sk, node) \ 897 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \ 898 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node) 899 #define sk_for_each_safe(__sk, tmp, list) \ 900 hlist_for_each_entry_safe(__sk, tmp, list, sk_node) 901 #define sk_for_each_bound(__sk, list) \ 902 hlist_for_each_entry(__sk, list, sk_bind_node) 903 #define sk_for_each_bound_bhash2(__sk, list) \ 904 hlist_for_each_entry(__sk, list, sk_bind2_node) 905 #define sk_for_each_bound_safe(__sk, tmp, list) \ 906 hlist_for_each_entry_safe(__sk, tmp, list, sk_bind_node) 907 908 /** 909 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset 910 * @tpos: the type * to use as a loop cursor. 911 * @pos: the &struct hlist_node to use as a loop cursor. 912 * @head: the head for your list. 913 * @offset: offset of hlist_node within the struct. 914 * 915 */ 916 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \ 917 for (pos = rcu_dereference(hlist_first_rcu(head)); \ 918 pos != NULL && \ 919 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ 920 pos = rcu_dereference(hlist_next_rcu(pos))) 921 922 static inline struct user_namespace *sk_user_ns(const struct sock *sk) 923 { 924 /* Careful only use this in a context where these parameters 925 * can not change and must all be valid, such as recvmsg from 926 * userspace. 927 */ 928 return sk->sk_socket->file->f_cred->user_ns; 929 } 930 931 /* Sock flags */ 932 enum sock_flags { 933 SOCK_DEAD, 934 SOCK_DONE, 935 SOCK_URGINLINE, 936 SOCK_KEEPOPEN, 937 SOCK_LINGER, 938 SOCK_DESTROY, 939 SOCK_BROADCAST, 940 SOCK_TIMESTAMP, 941 SOCK_ZAPPED, 942 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 943 SOCK_DBG, /* %SO_DEBUG setting */ 944 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 945 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 946 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 947 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 948 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 949 SOCK_FASYNC, /* fasync() active */ 950 SOCK_RXQ_OVFL, 951 SOCK_ZEROCOPY, /* buffers from userspace */ 952 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 953 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 954 * Will use last 4 bytes of packet sent from 955 * user-space instead. 956 */ 957 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ 958 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ 959 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ 960 SOCK_TXTIME, 961 SOCK_XDP, /* XDP is attached */ 962 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ 963 SOCK_RCVMARK, /* Receive SO_MARK ancillary data with packet */ 964 }; 965 966 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 967 968 static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk) 969 { 970 nsk->sk_flags = osk->sk_flags; 971 } 972 973 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 974 { 975 __set_bit(flag, &sk->sk_flags); 976 } 977 978 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 979 { 980 __clear_bit(flag, &sk->sk_flags); 981 } 982 983 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit, 984 int valbool) 985 { 986 if (valbool) 987 sock_set_flag(sk, bit); 988 else 989 sock_reset_flag(sk, bit); 990 } 991 992 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 993 { 994 return test_bit(flag, &sk->sk_flags); 995 } 996 997 #ifdef CONFIG_NET 998 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key); 999 static inline int sk_memalloc_socks(void) 1000 { 1001 return static_branch_unlikely(&memalloc_socks_key); 1002 } 1003 1004 void __receive_sock(struct file *file); 1005 #else 1006 1007 static inline int sk_memalloc_socks(void) 1008 { 1009 return 0; 1010 } 1011 1012 static inline void __receive_sock(struct file *file) 1013 { } 1014 #endif 1015 1016 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask) 1017 { 1018 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC); 1019 } 1020 1021 static inline void sk_acceptq_removed(struct sock *sk) 1022 { 1023 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1); 1024 } 1025 1026 static inline void sk_acceptq_added(struct sock *sk) 1027 { 1028 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1); 1029 } 1030 1031 /* Note: If you think the test should be: 1032 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog); 1033 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.") 1034 */ 1035 static inline bool sk_acceptq_is_full(const struct sock *sk) 1036 { 1037 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog); 1038 } 1039 1040 /* 1041 * Compute minimal free write space needed to queue new packets. 1042 */ 1043 static inline int sk_stream_min_wspace(const struct sock *sk) 1044 { 1045 return READ_ONCE(sk->sk_wmem_queued) >> 1; 1046 } 1047 1048 static inline int sk_stream_wspace(const struct sock *sk) 1049 { 1050 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued); 1051 } 1052 1053 static inline void sk_wmem_queued_add(struct sock *sk, int val) 1054 { 1055 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val); 1056 } 1057 1058 static inline void sk_forward_alloc_add(struct sock *sk, int val) 1059 { 1060 /* Paired with lockless reads of sk->sk_forward_alloc */ 1061 WRITE_ONCE(sk->sk_forward_alloc, sk->sk_forward_alloc + val); 1062 } 1063 1064 void sk_stream_write_space(struct sock *sk); 1065 1066 /* OOB backlog add */ 1067 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 1068 { 1069 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 1070 skb_dst_force(skb); 1071 1072 if (!sk->sk_backlog.tail) 1073 WRITE_ONCE(sk->sk_backlog.head, skb); 1074 else 1075 sk->sk_backlog.tail->next = skb; 1076 1077 WRITE_ONCE(sk->sk_backlog.tail, skb); 1078 skb->next = NULL; 1079 } 1080 1081 /* 1082 * Take into account size of receive queue and backlog queue 1083 * Do not take into account this skb truesize, 1084 * to allow even a single big packet to come. 1085 */ 1086 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit) 1087 { 1088 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 1089 1090 return qsize > limit; 1091 } 1092 1093 /* The per-socket spinlock must be held here. */ 1094 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 1095 unsigned int limit) 1096 { 1097 if (sk_rcvqueues_full(sk, limit)) 1098 return -ENOBUFS; 1099 1100 /* 1101 * If the skb was allocated from pfmemalloc reserves, only 1102 * allow SOCK_MEMALLOC sockets to use it as this socket is 1103 * helping free memory 1104 */ 1105 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) 1106 return -ENOMEM; 1107 1108 __sk_add_backlog(sk, skb); 1109 sk->sk_backlog.len += skb->truesize; 1110 return 0; 1111 } 1112 1113 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 1114 1115 INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)); 1116 INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)); 1117 1118 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 1119 { 1120 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 1121 return __sk_backlog_rcv(sk, skb); 1122 1123 return INDIRECT_CALL_INET(sk->sk_backlog_rcv, 1124 tcp_v6_do_rcv, 1125 tcp_v4_do_rcv, 1126 sk, skb); 1127 } 1128 1129 static inline void sk_incoming_cpu_update(struct sock *sk) 1130 { 1131 int cpu = raw_smp_processor_id(); 1132 1133 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu)) 1134 WRITE_ONCE(sk->sk_incoming_cpu, cpu); 1135 } 1136 1137 static inline void sock_rps_record_flow_hash(__u32 hash) 1138 { 1139 #ifdef CONFIG_RPS 1140 struct rps_sock_flow_table *sock_flow_table; 1141 1142 rcu_read_lock(); 1143 sock_flow_table = rcu_dereference(rps_sock_flow_table); 1144 rps_record_sock_flow(sock_flow_table, hash); 1145 rcu_read_unlock(); 1146 #endif 1147 } 1148 1149 static inline void sock_rps_record_flow(const struct sock *sk) 1150 { 1151 #ifdef CONFIG_RPS 1152 if (static_branch_unlikely(&rfs_needed)) { 1153 /* Reading sk->sk_rxhash might incur an expensive cache line 1154 * miss. 1155 * 1156 * TCP_ESTABLISHED does cover almost all states where RFS 1157 * might be useful, and is cheaper [1] than testing : 1158 * IPv4: inet_sk(sk)->inet_daddr 1159 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr) 1160 * OR an additional socket flag 1161 * [1] : sk_state and sk_prot are in the same cache line. 1162 */ 1163 if (sk->sk_state == TCP_ESTABLISHED) { 1164 /* This READ_ONCE() is paired with the WRITE_ONCE() 1165 * from sock_rps_save_rxhash() and sock_rps_reset_rxhash(). 1166 */ 1167 sock_rps_record_flow_hash(READ_ONCE(sk->sk_rxhash)); 1168 } 1169 } 1170 #endif 1171 } 1172 1173 static inline void sock_rps_save_rxhash(struct sock *sk, 1174 const struct sk_buff *skb) 1175 { 1176 #ifdef CONFIG_RPS 1177 /* The following WRITE_ONCE() is paired with the READ_ONCE() 1178 * here, and another one in sock_rps_record_flow(). 1179 */ 1180 if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash)) 1181 WRITE_ONCE(sk->sk_rxhash, skb->hash); 1182 #endif 1183 } 1184 1185 static inline void sock_rps_reset_rxhash(struct sock *sk) 1186 { 1187 #ifdef CONFIG_RPS 1188 /* Paired with READ_ONCE() in sock_rps_record_flow() */ 1189 WRITE_ONCE(sk->sk_rxhash, 0); 1190 #endif 1191 } 1192 1193 #define sk_wait_event(__sk, __timeo, __condition, __wait) \ 1194 ({ int __rc, __dis = __sk->sk_disconnects; \ 1195 release_sock(__sk); \ 1196 __rc = __condition; \ 1197 if (!__rc) { \ 1198 *(__timeo) = wait_woken(__wait, \ 1199 TASK_INTERRUPTIBLE, \ 1200 *(__timeo)); \ 1201 } \ 1202 sched_annotate_sleep(); \ 1203 lock_sock(__sk); \ 1204 __rc = __dis == __sk->sk_disconnects ? __condition : -EPIPE; \ 1205 __rc; \ 1206 }) 1207 1208 int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 1209 int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 1210 void sk_stream_wait_close(struct sock *sk, long timeo_p); 1211 int sk_stream_error(struct sock *sk, int flags, int err); 1212 void sk_stream_kill_queues(struct sock *sk); 1213 void sk_set_memalloc(struct sock *sk); 1214 void sk_clear_memalloc(struct sock *sk); 1215 1216 void __sk_flush_backlog(struct sock *sk); 1217 1218 static inline bool sk_flush_backlog(struct sock *sk) 1219 { 1220 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) { 1221 __sk_flush_backlog(sk); 1222 return true; 1223 } 1224 return false; 1225 } 1226 1227 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb); 1228 1229 struct request_sock_ops; 1230 struct timewait_sock_ops; 1231 struct inet_hashinfo; 1232 struct raw_hashinfo; 1233 struct smc_hashinfo; 1234 struct module; 1235 struct sk_psock; 1236 1237 /* 1238 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes 1239 * un-modified. Special care is taken when initializing object to zero. 1240 */ 1241 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1242 { 1243 if (offsetof(struct sock, sk_node.next) != 0) 1244 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1245 memset(&sk->sk_node.pprev, 0, 1246 size - offsetof(struct sock, sk_node.pprev)); 1247 } 1248 1249 /* Networking protocol blocks we attach to sockets. 1250 * socket layer -> transport layer interface 1251 */ 1252 struct proto { 1253 void (*close)(struct sock *sk, 1254 long timeout); 1255 int (*pre_connect)(struct sock *sk, 1256 struct sockaddr *uaddr, 1257 int addr_len); 1258 int (*connect)(struct sock *sk, 1259 struct sockaddr *uaddr, 1260 int addr_len); 1261 int (*disconnect)(struct sock *sk, int flags); 1262 1263 struct sock * (*accept)(struct sock *sk, int flags, int *err, 1264 bool kern); 1265 1266 int (*ioctl)(struct sock *sk, int cmd, 1267 int *karg); 1268 int (*init)(struct sock *sk); 1269 void (*destroy)(struct sock *sk); 1270 void (*shutdown)(struct sock *sk, int how); 1271 int (*setsockopt)(struct sock *sk, int level, 1272 int optname, sockptr_t optval, 1273 unsigned int optlen); 1274 int (*getsockopt)(struct sock *sk, int level, 1275 int optname, char __user *optval, 1276 int __user *option); 1277 void (*keepalive)(struct sock *sk, int valbool); 1278 #ifdef CONFIG_COMPAT 1279 int (*compat_ioctl)(struct sock *sk, 1280 unsigned int cmd, unsigned long arg); 1281 #endif 1282 int (*sendmsg)(struct sock *sk, struct msghdr *msg, 1283 size_t len); 1284 int (*recvmsg)(struct sock *sk, struct msghdr *msg, 1285 size_t len, int flags, int *addr_len); 1286 void (*splice_eof)(struct socket *sock); 1287 int (*bind)(struct sock *sk, 1288 struct sockaddr *addr, int addr_len); 1289 int (*bind_add)(struct sock *sk, 1290 struct sockaddr *addr, int addr_len); 1291 1292 int (*backlog_rcv) (struct sock *sk, 1293 struct sk_buff *skb); 1294 bool (*bpf_bypass_getsockopt)(int level, 1295 int optname); 1296 1297 void (*release_cb)(struct sock *sk); 1298 1299 /* Keeping track of sk's, looking them up, and port selection methods. */ 1300 int (*hash)(struct sock *sk); 1301 void (*unhash)(struct sock *sk); 1302 void (*rehash)(struct sock *sk); 1303 int (*get_port)(struct sock *sk, unsigned short snum); 1304 void (*put_port)(struct sock *sk); 1305 #ifdef CONFIG_BPF_SYSCALL 1306 int (*psock_update_sk_prot)(struct sock *sk, 1307 struct sk_psock *psock, 1308 bool restore); 1309 #endif 1310 1311 /* Keeping track of sockets in use */ 1312 #ifdef CONFIG_PROC_FS 1313 unsigned int inuse_idx; 1314 #endif 1315 1316 #if IS_ENABLED(CONFIG_MPTCP) 1317 int (*forward_alloc_get)(const struct sock *sk); 1318 #endif 1319 1320 bool (*stream_memory_free)(const struct sock *sk, int wake); 1321 bool (*sock_is_readable)(struct sock *sk); 1322 /* Memory pressure */ 1323 void (*enter_memory_pressure)(struct sock *sk); 1324 void (*leave_memory_pressure)(struct sock *sk); 1325 atomic_long_t *memory_allocated; /* Current allocated memory. */ 1326 int __percpu *per_cpu_fw_alloc; 1327 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 1328 1329 /* 1330 * Pressure flag: try to collapse. 1331 * Technical note: it is used by multiple contexts non atomically. 1332 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes. 1333 * All the __sk_mem_schedule() is of this nature: accounting 1334 * is strict, actions are advisory and have some latency. 1335 */ 1336 unsigned long *memory_pressure; 1337 long *sysctl_mem; 1338 1339 int *sysctl_wmem; 1340 int *sysctl_rmem; 1341 u32 sysctl_wmem_offset; 1342 u32 sysctl_rmem_offset; 1343 1344 int max_header; 1345 bool no_autobind; 1346 1347 struct kmem_cache *slab; 1348 unsigned int obj_size; 1349 unsigned int ipv6_pinfo_offset; 1350 slab_flags_t slab_flags; 1351 unsigned int useroffset; /* Usercopy region offset */ 1352 unsigned int usersize; /* Usercopy region size */ 1353 1354 unsigned int __percpu *orphan_count; 1355 1356 struct request_sock_ops *rsk_prot; 1357 struct timewait_sock_ops *twsk_prot; 1358 1359 union { 1360 struct inet_hashinfo *hashinfo; 1361 struct udp_table *udp_table; 1362 struct raw_hashinfo *raw_hash; 1363 struct smc_hashinfo *smc_hash; 1364 } h; 1365 1366 struct module *owner; 1367 1368 char name[32]; 1369 1370 struct list_head node; 1371 int (*diag_destroy)(struct sock *sk, int err); 1372 } __randomize_layout; 1373 1374 int proto_register(struct proto *prot, int alloc_slab); 1375 void proto_unregister(struct proto *prot); 1376 int sock_load_diag_module(int family, int protocol); 1377 1378 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake)); 1379 1380 static inline int sk_forward_alloc_get(const struct sock *sk) 1381 { 1382 #if IS_ENABLED(CONFIG_MPTCP) 1383 if (sk->sk_prot->forward_alloc_get) 1384 return sk->sk_prot->forward_alloc_get(sk); 1385 #endif 1386 return READ_ONCE(sk->sk_forward_alloc); 1387 } 1388 1389 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake) 1390 { 1391 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf)) 1392 return false; 1393 1394 return sk->sk_prot->stream_memory_free ? 1395 INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free, 1396 tcp_stream_memory_free, sk, wake) : true; 1397 } 1398 1399 static inline bool sk_stream_memory_free(const struct sock *sk) 1400 { 1401 return __sk_stream_memory_free(sk, 0); 1402 } 1403 1404 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake) 1405 { 1406 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && 1407 __sk_stream_memory_free(sk, wake); 1408 } 1409 1410 static inline bool sk_stream_is_writeable(const struct sock *sk) 1411 { 1412 return __sk_stream_is_writeable(sk, 0); 1413 } 1414 1415 static inline int sk_under_cgroup_hierarchy(struct sock *sk, 1416 struct cgroup *ancestor) 1417 { 1418 #ifdef CONFIG_SOCK_CGROUP_DATA 1419 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data), 1420 ancestor); 1421 #else 1422 return -ENOTSUPP; 1423 #endif 1424 } 1425 1426 static inline bool sk_has_memory_pressure(const struct sock *sk) 1427 { 1428 return sk->sk_prot->memory_pressure != NULL; 1429 } 1430 1431 static inline bool sk_under_global_memory_pressure(const struct sock *sk) 1432 { 1433 return sk->sk_prot->memory_pressure && 1434 !!READ_ONCE(*sk->sk_prot->memory_pressure); 1435 } 1436 1437 static inline bool sk_under_memory_pressure(const struct sock *sk) 1438 { 1439 if (!sk->sk_prot->memory_pressure) 1440 return false; 1441 1442 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 1443 mem_cgroup_under_socket_pressure(sk->sk_memcg)) 1444 return true; 1445 1446 return !!READ_ONCE(*sk->sk_prot->memory_pressure); 1447 } 1448 1449 static inline long 1450 proto_memory_allocated(const struct proto *prot) 1451 { 1452 return max(0L, atomic_long_read(prot->memory_allocated)); 1453 } 1454 1455 static inline long 1456 sk_memory_allocated(const struct sock *sk) 1457 { 1458 return proto_memory_allocated(sk->sk_prot); 1459 } 1460 1461 /* 1 MB per cpu, in page units */ 1462 #define SK_MEMORY_PCPU_RESERVE (1 << (20 - PAGE_SHIFT)) 1463 extern int sysctl_mem_pcpu_rsv; 1464 1465 static inline void proto_memory_pcpu_drain(struct proto *proto) 1466 { 1467 int val = this_cpu_xchg(*proto->per_cpu_fw_alloc, 0); 1468 1469 if (val) 1470 atomic_long_add(val, proto->memory_allocated); 1471 } 1472 1473 static inline void 1474 sk_memory_allocated_add(const struct sock *sk, int val) 1475 { 1476 struct proto *proto = sk->sk_prot; 1477 1478 val = this_cpu_add_return(*proto->per_cpu_fw_alloc, val); 1479 1480 if (unlikely(val >= READ_ONCE(sysctl_mem_pcpu_rsv))) 1481 proto_memory_pcpu_drain(proto); 1482 } 1483 1484 static inline void 1485 sk_memory_allocated_sub(const struct sock *sk, int val) 1486 { 1487 struct proto *proto = sk->sk_prot; 1488 1489 val = this_cpu_sub_return(*proto->per_cpu_fw_alloc, val); 1490 1491 if (unlikely(val <= -READ_ONCE(sysctl_mem_pcpu_rsv))) 1492 proto_memory_pcpu_drain(proto); 1493 } 1494 1495 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16 1496 1497 static inline void sk_sockets_allocated_dec(struct sock *sk) 1498 { 1499 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1, 1500 SK_ALLOC_PERCPU_COUNTER_BATCH); 1501 } 1502 1503 static inline void sk_sockets_allocated_inc(struct sock *sk) 1504 { 1505 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1, 1506 SK_ALLOC_PERCPU_COUNTER_BATCH); 1507 } 1508 1509 static inline u64 1510 sk_sockets_allocated_read_positive(struct sock *sk) 1511 { 1512 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated); 1513 } 1514 1515 static inline int 1516 proto_sockets_allocated_sum_positive(struct proto *prot) 1517 { 1518 return percpu_counter_sum_positive(prot->sockets_allocated); 1519 } 1520 1521 static inline bool 1522 proto_memory_pressure(struct proto *prot) 1523 { 1524 if (!prot->memory_pressure) 1525 return false; 1526 return !!READ_ONCE(*prot->memory_pressure); 1527 } 1528 1529 1530 #ifdef CONFIG_PROC_FS 1531 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 1532 struct prot_inuse { 1533 int all; 1534 int val[PROTO_INUSE_NR]; 1535 }; 1536 1537 static inline void sock_prot_inuse_add(const struct net *net, 1538 const struct proto *prot, int val) 1539 { 1540 this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val); 1541 } 1542 1543 static inline void sock_inuse_add(const struct net *net, int val) 1544 { 1545 this_cpu_add(net->core.prot_inuse->all, val); 1546 } 1547 1548 int sock_prot_inuse_get(struct net *net, struct proto *proto); 1549 int sock_inuse_get(struct net *net); 1550 #else 1551 static inline void sock_prot_inuse_add(const struct net *net, 1552 const struct proto *prot, int val) 1553 { 1554 } 1555 1556 static inline void sock_inuse_add(const struct net *net, int val) 1557 { 1558 } 1559 #endif 1560 1561 1562 /* With per-bucket locks this operation is not-atomic, so that 1563 * this version is not worse. 1564 */ 1565 static inline int __sk_prot_rehash(struct sock *sk) 1566 { 1567 sk->sk_prot->unhash(sk); 1568 return sk->sk_prot->hash(sk); 1569 } 1570 1571 /* About 10 seconds */ 1572 #define SOCK_DESTROY_TIME (10*HZ) 1573 1574 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1575 #define PROT_SOCK 1024 1576 1577 #define SHUTDOWN_MASK 3 1578 #define RCV_SHUTDOWN 1 1579 #define SEND_SHUTDOWN 2 1580 1581 #define SOCK_BINDADDR_LOCK 4 1582 #define SOCK_BINDPORT_LOCK 8 1583 1584 struct socket_alloc { 1585 struct socket socket; 1586 struct inode vfs_inode; 1587 }; 1588 1589 static inline struct socket *SOCKET_I(struct inode *inode) 1590 { 1591 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1592 } 1593 1594 static inline struct inode *SOCK_INODE(struct socket *socket) 1595 { 1596 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1597 } 1598 1599 /* 1600 * Functions for memory accounting 1601 */ 1602 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind); 1603 int __sk_mem_schedule(struct sock *sk, int size, int kind); 1604 void __sk_mem_reduce_allocated(struct sock *sk, int amount); 1605 void __sk_mem_reclaim(struct sock *sk, int amount); 1606 1607 #define SK_MEM_SEND 0 1608 #define SK_MEM_RECV 1 1609 1610 /* sysctl_mem values are in pages */ 1611 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1612 { 1613 return READ_ONCE(sk->sk_prot->sysctl_mem[index]); 1614 } 1615 1616 static inline int sk_mem_pages(int amt) 1617 { 1618 return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT; 1619 } 1620 1621 static inline bool sk_has_account(struct sock *sk) 1622 { 1623 /* return true if protocol supports memory accounting */ 1624 return !!sk->sk_prot->memory_allocated; 1625 } 1626 1627 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1628 { 1629 int delta; 1630 1631 if (!sk_has_account(sk)) 1632 return true; 1633 delta = size - sk->sk_forward_alloc; 1634 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND); 1635 } 1636 1637 static inline bool 1638 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size) 1639 { 1640 int delta; 1641 1642 if (!sk_has_account(sk)) 1643 return true; 1644 delta = size - sk->sk_forward_alloc; 1645 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) || 1646 skb_pfmemalloc(skb); 1647 } 1648 1649 static inline int sk_unused_reserved_mem(const struct sock *sk) 1650 { 1651 int unused_mem; 1652 1653 if (likely(!sk->sk_reserved_mem)) 1654 return 0; 1655 1656 unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued - 1657 atomic_read(&sk->sk_rmem_alloc); 1658 1659 return unused_mem > 0 ? unused_mem : 0; 1660 } 1661 1662 static inline void sk_mem_reclaim(struct sock *sk) 1663 { 1664 int reclaimable; 1665 1666 if (!sk_has_account(sk)) 1667 return; 1668 1669 reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk); 1670 1671 if (reclaimable >= (int)PAGE_SIZE) 1672 __sk_mem_reclaim(sk, reclaimable); 1673 } 1674 1675 static inline void sk_mem_reclaim_final(struct sock *sk) 1676 { 1677 sk->sk_reserved_mem = 0; 1678 sk_mem_reclaim(sk); 1679 } 1680 1681 static inline void sk_mem_charge(struct sock *sk, int size) 1682 { 1683 if (!sk_has_account(sk)) 1684 return; 1685 sk_forward_alloc_add(sk, -size); 1686 } 1687 1688 static inline void sk_mem_uncharge(struct sock *sk, int size) 1689 { 1690 if (!sk_has_account(sk)) 1691 return; 1692 sk_forward_alloc_add(sk, size); 1693 sk_mem_reclaim(sk); 1694 } 1695 1696 /* 1697 * Macro so as to not evaluate some arguments when 1698 * lockdep is not enabled. 1699 * 1700 * Mark both the sk_lock and the sk_lock.slock as a 1701 * per-address-family lock class. 1702 */ 1703 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1704 do { \ 1705 sk->sk_lock.owned = 0; \ 1706 init_waitqueue_head(&sk->sk_lock.wq); \ 1707 spin_lock_init(&(sk)->sk_lock.slock); \ 1708 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1709 sizeof((sk)->sk_lock)); \ 1710 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1711 (skey), (sname)); \ 1712 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1713 } while (0) 1714 1715 static inline bool lockdep_sock_is_held(const struct sock *sk) 1716 { 1717 return lockdep_is_held(&sk->sk_lock) || 1718 lockdep_is_held(&sk->sk_lock.slock); 1719 } 1720 1721 void lock_sock_nested(struct sock *sk, int subclass); 1722 1723 static inline void lock_sock(struct sock *sk) 1724 { 1725 lock_sock_nested(sk, 0); 1726 } 1727 1728 void __lock_sock(struct sock *sk); 1729 void __release_sock(struct sock *sk); 1730 void release_sock(struct sock *sk); 1731 1732 /* BH context may only use the following locking interface. */ 1733 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1734 #define bh_lock_sock_nested(__sk) \ 1735 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1736 SINGLE_DEPTH_NESTING) 1737 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1738 1739 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock); 1740 1741 /** 1742 * lock_sock_fast - fast version of lock_sock 1743 * @sk: socket 1744 * 1745 * This version should be used for very small section, where process wont block 1746 * return false if fast path is taken: 1747 * 1748 * sk_lock.slock locked, owned = 0, BH disabled 1749 * 1750 * return true if slow path is taken: 1751 * 1752 * sk_lock.slock unlocked, owned = 1, BH enabled 1753 */ 1754 static inline bool lock_sock_fast(struct sock *sk) 1755 { 1756 /* The sk_lock has mutex_lock() semantics here. */ 1757 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 1758 1759 return __lock_sock_fast(sk); 1760 } 1761 1762 /* fast socket lock variant for caller already holding a [different] socket lock */ 1763 static inline bool lock_sock_fast_nested(struct sock *sk) 1764 { 1765 mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_); 1766 1767 return __lock_sock_fast(sk); 1768 } 1769 1770 /** 1771 * unlock_sock_fast - complement of lock_sock_fast 1772 * @sk: socket 1773 * @slow: slow mode 1774 * 1775 * fast unlock socket for user context. 1776 * If slow mode is on, we call regular release_sock() 1777 */ 1778 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1779 __releases(&sk->sk_lock.slock) 1780 { 1781 if (slow) { 1782 release_sock(sk); 1783 __release(&sk->sk_lock.slock); 1784 } else { 1785 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1786 spin_unlock_bh(&sk->sk_lock.slock); 1787 } 1788 } 1789 1790 void sockopt_lock_sock(struct sock *sk); 1791 void sockopt_release_sock(struct sock *sk); 1792 bool sockopt_ns_capable(struct user_namespace *ns, int cap); 1793 bool sockopt_capable(int cap); 1794 1795 /* Used by processes to "lock" a socket state, so that 1796 * interrupts and bottom half handlers won't change it 1797 * from under us. It essentially blocks any incoming 1798 * packets, so that we won't get any new data or any 1799 * packets that change the state of the socket. 1800 * 1801 * While locked, BH processing will add new packets to 1802 * the backlog queue. This queue is processed by the 1803 * owner of the socket lock right before it is released. 1804 * 1805 * Since ~2.3.5 it is also exclusive sleep lock serializing 1806 * accesses from user process context. 1807 */ 1808 1809 static inline void sock_owned_by_me(const struct sock *sk) 1810 { 1811 #ifdef CONFIG_LOCKDEP 1812 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks); 1813 #endif 1814 } 1815 1816 static inline void sock_not_owned_by_me(const struct sock *sk) 1817 { 1818 #ifdef CONFIG_LOCKDEP 1819 WARN_ON_ONCE(lockdep_sock_is_held(sk) && debug_locks); 1820 #endif 1821 } 1822 1823 static inline bool sock_owned_by_user(const struct sock *sk) 1824 { 1825 sock_owned_by_me(sk); 1826 return sk->sk_lock.owned; 1827 } 1828 1829 static inline bool sock_owned_by_user_nocheck(const struct sock *sk) 1830 { 1831 return sk->sk_lock.owned; 1832 } 1833 1834 static inline void sock_release_ownership(struct sock *sk) 1835 { 1836 if (sock_owned_by_user_nocheck(sk)) { 1837 sk->sk_lock.owned = 0; 1838 1839 /* The sk_lock has mutex_unlock() semantics: */ 1840 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1841 } 1842 } 1843 1844 /* no reclassification while locks are held */ 1845 static inline bool sock_allow_reclassification(const struct sock *csk) 1846 { 1847 struct sock *sk = (struct sock *)csk; 1848 1849 return !sock_owned_by_user_nocheck(sk) && 1850 !spin_is_locked(&sk->sk_lock.slock); 1851 } 1852 1853 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1854 struct proto *prot, int kern); 1855 void sk_free(struct sock *sk); 1856 void sk_destruct(struct sock *sk); 1857 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); 1858 void sk_free_unlock_clone(struct sock *sk); 1859 1860 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1861 gfp_t priority); 1862 void __sock_wfree(struct sk_buff *skb); 1863 void sock_wfree(struct sk_buff *skb); 1864 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 1865 gfp_t priority); 1866 void skb_orphan_partial(struct sk_buff *skb); 1867 void sock_rfree(struct sk_buff *skb); 1868 void sock_efree(struct sk_buff *skb); 1869 #ifdef CONFIG_INET 1870 void sock_edemux(struct sk_buff *skb); 1871 void sock_pfree(struct sk_buff *skb); 1872 #else 1873 #define sock_edemux sock_efree 1874 #endif 1875 1876 int sk_setsockopt(struct sock *sk, int level, int optname, 1877 sockptr_t optval, unsigned int optlen); 1878 int sock_setsockopt(struct socket *sock, int level, int op, 1879 sockptr_t optval, unsigned int optlen); 1880 int do_sock_setsockopt(struct socket *sock, bool compat, int level, 1881 int optname, sockptr_t optval, int optlen); 1882 int do_sock_getsockopt(struct socket *sock, bool compat, int level, 1883 int optname, sockptr_t optval, sockptr_t optlen); 1884 1885 int sk_getsockopt(struct sock *sk, int level, int optname, 1886 sockptr_t optval, sockptr_t optlen); 1887 int sock_gettstamp(struct socket *sock, void __user *userstamp, 1888 bool timeval, bool time32); 1889 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1890 unsigned long data_len, int noblock, 1891 int *errcode, int max_page_order); 1892 1893 static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk, 1894 unsigned long size, 1895 int noblock, int *errcode) 1896 { 1897 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1898 } 1899 1900 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); 1901 void sock_kfree_s(struct sock *sk, void *mem, int size); 1902 void sock_kzfree_s(struct sock *sk, void *mem, int size); 1903 void sk_send_sigurg(struct sock *sk); 1904 1905 static inline void sock_replace_proto(struct sock *sk, struct proto *proto) 1906 { 1907 if (sk->sk_socket) 1908 clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags); 1909 WRITE_ONCE(sk->sk_prot, proto); 1910 } 1911 1912 struct sockcm_cookie { 1913 u64 transmit_time; 1914 u32 mark; 1915 u32 tsflags; 1916 }; 1917 1918 static inline void sockcm_init(struct sockcm_cookie *sockc, 1919 const struct sock *sk) 1920 { 1921 *sockc = (struct sockcm_cookie) { 1922 .tsflags = READ_ONCE(sk->sk_tsflags) 1923 }; 1924 } 1925 1926 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg, 1927 struct sockcm_cookie *sockc); 1928 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1929 struct sockcm_cookie *sockc); 1930 1931 /* 1932 * Functions to fill in entries in struct proto_ops when a protocol 1933 * does not implement a particular function. 1934 */ 1935 int sock_no_bind(struct socket *, struct sockaddr *, int); 1936 int sock_no_connect(struct socket *, struct sockaddr *, int, int); 1937 int sock_no_socketpair(struct socket *, struct socket *); 1938 int sock_no_accept(struct socket *, struct socket *, int, bool); 1939 int sock_no_getname(struct socket *, struct sockaddr *, int); 1940 int sock_no_ioctl(struct socket *, unsigned int, unsigned long); 1941 int sock_no_listen(struct socket *, int); 1942 int sock_no_shutdown(struct socket *, int); 1943 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t); 1944 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len); 1945 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int); 1946 int sock_no_mmap(struct file *file, struct socket *sock, 1947 struct vm_area_struct *vma); 1948 1949 /* 1950 * Functions to fill in entries in struct proto_ops when a protocol 1951 * uses the inet style. 1952 */ 1953 int sock_common_getsockopt(struct socket *sock, int level, int optname, 1954 char __user *optval, int __user *optlen); 1955 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1956 int flags); 1957 int sock_common_setsockopt(struct socket *sock, int level, int optname, 1958 sockptr_t optval, unsigned int optlen); 1959 1960 void sk_common_release(struct sock *sk); 1961 1962 /* 1963 * Default socket callbacks and setup code 1964 */ 1965 1966 /* Initialise core socket variables using an explicit uid. */ 1967 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid); 1968 1969 /* Initialise core socket variables. 1970 * Assumes struct socket *sock is embedded in a struct socket_alloc. 1971 */ 1972 void sock_init_data(struct socket *sock, struct sock *sk); 1973 1974 /* 1975 * Socket reference counting postulates. 1976 * 1977 * * Each user of socket SHOULD hold a reference count. 1978 * * Each access point to socket (an hash table bucket, reference from a list, 1979 * running timer, skb in flight MUST hold a reference count. 1980 * * When reference count hits 0, it means it will never increase back. 1981 * * When reference count hits 0, it means that no references from 1982 * outside exist to this socket and current process on current CPU 1983 * is last user and may/should destroy this socket. 1984 * * sk_free is called from any context: process, BH, IRQ. When 1985 * it is called, socket has no references from outside -> sk_free 1986 * may release descendant resources allocated by the socket, but 1987 * to the time when it is called, socket is NOT referenced by any 1988 * hash tables, lists etc. 1989 * * Packets, delivered from outside (from network or from another process) 1990 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1991 * when they sit in queue. Otherwise, packets will leak to hole, when 1992 * socket is looked up by one cpu and unhasing is made by another CPU. 1993 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1994 * (leak to backlog). Packet socket does all the processing inside 1995 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1996 * use separate SMP lock, so that they are prone too. 1997 */ 1998 1999 /* Ungrab socket and destroy it, if it was the last reference. */ 2000 static inline void sock_put(struct sock *sk) 2001 { 2002 if (refcount_dec_and_test(&sk->sk_refcnt)) 2003 sk_free(sk); 2004 } 2005 /* Generic version of sock_put(), dealing with all sockets 2006 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...) 2007 */ 2008 void sock_gen_put(struct sock *sk); 2009 2010 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested, 2011 unsigned int trim_cap, bool refcounted); 2012 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 2013 const int nested) 2014 { 2015 return __sk_receive_skb(sk, skb, nested, 1, true); 2016 } 2017 2018 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 2019 { 2020 /* sk_tx_queue_mapping accept only upto a 16-bit value */ 2021 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) 2022 return; 2023 /* Paired with READ_ONCE() in sk_tx_queue_get() and 2024 * other WRITE_ONCE() because socket lock might be not held. 2025 */ 2026 WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue); 2027 } 2028 2029 #define NO_QUEUE_MAPPING USHRT_MAX 2030 2031 static inline void sk_tx_queue_clear(struct sock *sk) 2032 { 2033 /* Paired with READ_ONCE() in sk_tx_queue_get() and 2034 * other WRITE_ONCE() because socket lock might be not held. 2035 */ 2036 WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING); 2037 } 2038 2039 static inline int sk_tx_queue_get(const struct sock *sk) 2040 { 2041 if (sk) { 2042 /* Paired with WRITE_ONCE() in sk_tx_queue_clear() 2043 * and sk_tx_queue_set(). 2044 */ 2045 int val = READ_ONCE(sk->sk_tx_queue_mapping); 2046 2047 if (val != NO_QUEUE_MAPPING) 2048 return val; 2049 } 2050 return -1; 2051 } 2052 2053 static inline void __sk_rx_queue_set(struct sock *sk, 2054 const struct sk_buff *skb, 2055 bool force_set) 2056 { 2057 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 2058 if (skb_rx_queue_recorded(skb)) { 2059 u16 rx_queue = skb_get_rx_queue(skb); 2060 2061 if (force_set || 2062 unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue)) 2063 WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue); 2064 } 2065 #endif 2066 } 2067 2068 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) 2069 { 2070 __sk_rx_queue_set(sk, skb, true); 2071 } 2072 2073 static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb) 2074 { 2075 __sk_rx_queue_set(sk, skb, false); 2076 } 2077 2078 static inline void sk_rx_queue_clear(struct sock *sk) 2079 { 2080 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 2081 WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING); 2082 #endif 2083 } 2084 2085 static inline int sk_rx_queue_get(const struct sock *sk) 2086 { 2087 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 2088 if (sk) { 2089 int res = READ_ONCE(sk->sk_rx_queue_mapping); 2090 2091 if (res != NO_QUEUE_MAPPING) 2092 return res; 2093 } 2094 #endif 2095 2096 return -1; 2097 } 2098 2099 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 2100 { 2101 sk->sk_socket = sock; 2102 } 2103 2104 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 2105 { 2106 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 2107 return &rcu_dereference_raw(sk->sk_wq)->wait; 2108 } 2109 /* Detach socket from process context. 2110 * Announce socket dead, detach it from wait queue and inode. 2111 * Note that parent inode held reference count on this struct sock, 2112 * we do not release it in this function, because protocol 2113 * probably wants some additional cleanups or even continuing 2114 * to work with this socket (TCP). 2115 */ 2116 static inline void sock_orphan(struct sock *sk) 2117 { 2118 write_lock_bh(&sk->sk_callback_lock); 2119 sock_set_flag(sk, SOCK_DEAD); 2120 sk_set_socket(sk, NULL); 2121 sk->sk_wq = NULL; 2122 write_unlock_bh(&sk->sk_callback_lock); 2123 } 2124 2125 static inline void sock_graft(struct sock *sk, struct socket *parent) 2126 { 2127 WARN_ON(parent->sk); 2128 write_lock_bh(&sk->sk_callback_lock); 2129 rcu_assign_pointer(sk->sk_wq, &parent->wq); 2130 parent->sk = sk; 2131 sk_set_socket(sk, parent); 2132 sk->sk_uid = SOCK_INODE(parent)->i_uid; 2133 security_sock_graft(sk, parent); 2134 write_unlock_bh(&sk->sk_callback_lock); 2135 } 2136 2137 kuid_t sock_i_uid(struct sock *sk); 2138 unsigned long __sock_i_ino(struct sock *sk); 2139 unsigned long sock_i_ino(struct sock *sk); 2140 2141 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk) 2142 { 2143 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0); 2144 } 2145 2146 static inline u32 net_tx_rndhash(void) 2147 { 2148 u32 v = get_random_u32(); 2149 2150 return v ?: 1; 2151 } 2152 2153 static inline void sk_set_txhash(struct sock *sk) 2154 { 2155 /* This pairs with READ_ONCE() in skb_set_hash_from_sk() */ 2156 WRITE_ONCE(sk->sk_txhash, net_tx_rndhash()); 2157 } 2158 2159 static inline bool sk_rethink_txhash(struct sock *sk) 2160 { 2161 if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) { 2162 sk_set_txhash(sk); 2163 return true; 2164 } 2165 return false; 2166 } 2167 2168 static inline struct dst_entry * 2169 __sk_dst_get(const struct sock *sk) 2170 { 2171 return rcu_dereference_check(sk->sk_dst_cache, 2172 lockdep_sock_is_held(sk)); 2173 } 2174 2175 static inline struct dst_entry * 2176 sk_dst_get(const struct sock *sk) 2177 { 2178 struct dst_entry *dst; 2179 2180 rcu_read_lock(); 2181 dst = rcu_dereference(sk->sk_dst_cache); 2182 if (dst && !rcuref_get(&dst->__rcuref)) 2183 dst = NULL; 2184 rcu_read_unlock(); 2185 return dst; 2186 } 2187 2188 static inline void __dst_negative_advice(struct sock *sk) 2189 { 2190 struct dst_entry *dst = __sk_dst_get(sk); 2191 2192 if (dst && dst->ops->negative_advice) 2193 dst->ops->negative_advice(sk, dst); 2194 } 2195 2196 static inline void dst_negative_advice(struct sock *sk) 2197 { 2198 sk_rethink_txhash(sk); 2199 __dst_negative_advice(sk); 2200 } 2201 2202 static inline void 2203 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 2204 { 2205 struct dst_entry *old_dst; 2206 2207 sk_tx_queue_clear(sk); 2208 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 2209 old_dst = rcu_dereference_protected(sk->sk_dst_cache, 2210 lockdep_sock_is_held(sk)); 2211 rcu_assign_pointer(sk->sk_dst_cache, dst); 2212 dst_release(old_dst); 2213 } 2214 2215 static inline void 2216 sk_dst_set(struct sock *sk, struct dst_entry *dst) 2217 { 2218 struct dst_entry *old_dst; 2219 2220 sk_tx_queue_clear(sk); 2221 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 2222 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst); 2223 dst_release(old_dst); 2224 } 2225 2226 static inline void 2227 __sk_dst_reset(struct sock *sk) 2228 { 2229 __sk_dst_set(sk, NULL); 2230 } 2231 2232 static inline void 2233 sk_dst_reset(struct sock *sk) 2234 { 2235 sk_dst_set(sk, NULL); 2236 } 2237 2238 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 2239 2240 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 2241 2242 static inline void sk_dst_confirm(struct sock *sk) 2243 { 2244 if (!READ_ONCE(sk->sk_dst_pending_confirm)) 2245 WRITE_ONCE(sk->sk_dst_pending_confirm, 1); 2246 } 2247 2248 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n) 2249 { 2250 if (skb_get_dst_pending_confirm(skb)) { 2251 struct sock *sk = skb->sk; 2252 2253 if (sk && READ_ONCE(sk->sk_dst_pending_confirm)) 2254 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 2255 neigh_confirm(n); 2256 } 2257 } 2258 2259 bool sk_mc_loop(struct sock *sk); 2260 2261 static inline bool sk_can_gso(const struct sock *sk) 2262 { 2263 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 2264 } 2265 2266 void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 2267 2268 static inline void sk_gso_disable(struct sock *sk) 2269 { 2270 sk->sk_gso_disabled = 1; 2271 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 2272 } 2273 2274 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 2275 struct iov_iter *from, char *to, 2276 int copy, int offset) 2277 { 2278 if (skb->ip_summed == CHECKSUM_NONE) { 2279 __wsum csum = 0; 2280 if (!csum_and_copy_from_iter_full(to, copy, &csum, from)) 2281 return -EFAULT; 2282 skb->csum = csum_block_add(skb->csum, csum, offset); 2283 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 2284 if (!copy_from_iter_full_nocache(to, copy, from)) 2285 return -EFAULT; 2286 } else if (!copy_from_iter_full(to, copy, from)) 2287 return -EFAULT; 2288 2289 return 0; 2290 } 2291 2292 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 2293 struct iov_iter *from, int copy) 2294 { 2295 int err, offset = skb->len; 2296 2297 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 2298 copy, offset); 2299 if (err) 2300 __skb_trim(skb, offset); 2301 2302 return err; 2303 } 2304 2305 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from, 2306 struct sk_buff *skb, 2307 struct page *page, 2308 int off, int copy) 2309 { 2310 int err; 2311 2312 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 2313 copy, skb->len); 2314 if (err) 2315 return err; 2316 2317 skb_len_add(skb, copy); 2318 sk_wmem_queued_add(sk, copy); 2319 sk_mem_charge(sk, copy); 2320 return 0; 2321 } 2322 2323 /** 2324 * sk_wmem_alloc_get - returns write allocations 2325 * @sk: socket 2326 * 2327 * Return: sk_wmem_alloc minus initial offset of one 2328 */ 2329 static inline int sk_wmem_alloc_get(const struct sock *sk) 2330 { 2331 return refcount_read(&sk->sk_wmem_alloc) - 1; 2332 } 2333 2334 /** 2335 * sk_rmem_alloc_get - returns read allocations 2336 * @sk: socket 2337 * 2338 * Return: sk_rmem_alloc 2339 */ 2340 static inline int sk_rmem_alloc_get(const struct sock *sk) 2341 { 2342 return atomic_read(&sk->sk_rmem_alloc); 2343 } 2344 2345 /** 2346 * sk_has_allocations - check if allocations are outstanding 2347 * @sk: socket 2348 * 2349 * Return: true if socket has write or read allocations 2350 */ 2351 static inline bool sk_has_allocations(const struct sock *sk) 2352 { 2353 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 2354 } 2355 2356 /** 2357 * skwq_has_sleeper - check if there are any waiting processes 2358 * @wq: struct socket_wq 2359 * 2360 * Return: true if socket_wq has waiting processes 2361 * 2362 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory 2363 * barrier call. They were added due to the race found within the tcp code. 2364 * 2365 * Consider following tcp code paths:: 2366 * 2367 * CPU1 CPU2 2368 * sys_select receive packet 2369 * ... ... 2370 * __add_wait_queue update tp->rcv_nxt 2371 * ... ... 2372 * tp->rcv_nxt check sock_def_readable 2373 * ... { 2374 * schedule rcu_read_lock(); 2375 * wq = rcu_dereference(sk->sk_wq); 2376 * if (wq && waitqueue_active(&wq->wait)) 2377 * wake_up_interruptible(&wq->wait) 2378 * ... 2379 * } 2380 * 2381 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 2382 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 2383 * could then endup calling schedule and sleep forever if there are no more 2384 * data on the socket. 2385 * 2386 */ 2387 static inline bool skwq_has_sleeper(struct socket_wq *wq) 2388 { 2389 return wq && wq_has_sleeper(&wq->wait); 2390 } 2391 2392 /** 2393 * sock_poll_wait - place memory barrier behind the poll_wait call. 2394 * @filp: file 2395 * @sock: socket to wait on 2396 * @p: poll_table 2397 * 2398 * See the comments in the wq_has_sleeper function. 2399 */ 2400 static inline void sock_poll_wait(struct file *filp, struct socket *sock, 2401 poll_table *p) 2402 { 2403 if (!poll_does_not_wait(p)) { 2404 poll_wait(filp, &sock->wq.wait, p); 2405 /* We need to be sure we are in sync with the 2406 * socket flags modification. 2407 * 2408 * This memory barrier is paired in the wq_has_sleeper. 2409 */ 2410 smp_mb(); 2411 } 2412 } 2413 2414 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk) 2415 { 2416 /* This pairs with WRITE_ONCE() in sk_set_txhash() */ 2417 u32 txhash = READ_ONCE(sk->sk_txhash); 2418 2419 if (txhash) { 2420 skb->l4_hash = 1; 2421 skb->hash = txhash; 2422 } 2423 } 2424 2425 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk); 2426 2427 /* 2428 * Queue a received datagram if it will fit. Stream and sequenced 2429 * protocols can't normally use this as they need to fit buffers in 2430 * and play with them. 2431 * 2432 * Inlined as it's very short and called for pretty much every 2433 * packet ever received. 2434 */ 2435 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 2436 { 2437 skb_orphan(skb); 2438 skb->sk = sk; 2439 skb->destructor = sock_rfree; 2440 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 2441 sk_mem_charge(sk, skb->truesize); 2442 } 2443 2444 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk) 2445 { 2446 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) { 2447 skb_orphan(skb); 2448 skb->destructor = sock_efree; 2449 skb->sk = sk; 2450 return true; 2451 } 2452 return false; 2453 } 2454 2455 static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk) 2456 { 2457 skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); 2458 if (skb) { 2459 if (sk_rmem_schedule(sk, skb, skb->truesize)) { 2460 skb_set_owner_r(skb, sk); 2461 return skb; 2462 } 2463 __kfree_skb(skb); 2464 } 2465 return NULL; 2466 } 2467 2468 static inline void skb_prepare_for_gro(struct sk_buff *skb) 2469 { 2470 if (skb->destructor != sock_wfree) { 2471 skb_orphan(skb); 2472 return; 2473 } 2474 skb->slow_gro = 1; 2475 } 2476 2477 void sk_reset_timer(struct sock *sk, struct timer_list *timer, 2478 unsigned long expires); 2479 2480 void sk_stop_timer(struct sock *sk, struct timer_list *timer); 2481 2482 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer); 2483 2484 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, 2485 struct sk_buff *skb, unsigned int flags, 2486 void (*destructor)(struct sock *sk, 2487 struct sk_buff *skb)); 2488 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2489 2490 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb, 2491 enum skb_drop_reason *reason); 2492 2493 static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 2494 { 2495 return sock_queue_rcv_skb_reason(sk, skb, NULL); 2496 } 2497 2498 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 2499 struct sk_buff *sock_dequeue_err_skb(struct sock *sk); 2500 2501 /* 2502 * Recover an error report and clear atomically 2503 */ 2504 2505 static inline int sock_error(struct sock *sk) 2506 { 2507 int err; 2508 2509 /* Avoid an atomic operation for the common case. 2510 * This is racy since another cpu/thread can change sk_err under us. 2511 */ 2512 if (likely(data_race(!sk->sk_err))) 2513 return 0; 2514 2515 err = xchg(&sk->sk_err, 0); 2516 return -err; 2517 } 2518 2519 void sk_error_report(struct sock *sk); 2520 2521 static inline unsigned long sock_wspace(struct sock *sk) 2522 { 2523 int amt = 0; 2524 2525 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 2526 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc); 2527 if (amt < 0) 2528 amt = 0; 2529 } 2530 return amt; 2531 } 2532 2533 /* Note: 2534 * We use sk->sk_wq_raw, from contexts knowing this 2535 * pointer is not NULL and cannot disappear/change. 2536 */ 2537 static inline void sk_set_bit(int nr, struct sock *sk) 2538 { 2539 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2540 !sock_flag(sk, SOCK_FASYNC)) 2541 return; 2542 2543 set_bit(nr, &sk->sk_wq_raw->flags); 2544 } 2545 2546 static inline void sk_clear_bit(int nr, struct sock *sk) 2547 { 2548 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2549 !sock_flag(sk, SOCK_FASYNC)) 2550 return; 2551 2552 clear_bit(nr, &sk->sk_wq_raw->flags); 2553 } 2554 2555 static inline void sk_wake_async(const struct sock *sk, int how, int band) 2556 { 2557 if (sock_flag(sk, SOCK_FASYNC)) { 2558 rcu_read_lock(); 2559 sock_wake_async(rcu_dereference(sk->sk_wq), how, band); 2560 rcu_read_unlock(); 2561 } 2562 } 2563 2564 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might 2565 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak. 2566 * Note: for send buffers, TCP works better if we can build two skbs at 2567 * minimum. 2568 */ 2569 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) 2570 2571 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2) 2572 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE 2573 2574 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2575 { 2576 u32 val; 2577 2578 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 2579 return; 2580 2581 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2582 val = max_t(u32, val, sk_unused_reserved_mem(sk)); 2583 2584 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF)); 2585 } 2586 2587 /** 2588 * sk_page_frag - return an appropriate page_frag 2589 * @sk: socket 2590 * 2591 * Use the per task page_frag instead of the per socket one for 2592 * optimization when we know that we're in process context and own 2593 * everything that's associated with %current. 2594 * 2595 * Both direct reclaim and page faults can nest inside other 2596 * socket operations and end up recursing into sk_page_frag() 2597 * while it's already in use: explicitly avoid task page_frag 2598 * when users disable sk_use_task_frag. 2599 * 2600 * Return: a per task page_frag if context allows that, 2601 * otherwise a per socket one. 2602 */ 2603 static inline struct page_frag *sk_page_frag(struct sock *sk) 2604 { 2605 if (sk->sk_use_task_frag) 2606 return ¤t->task_frag; 2607 2608 return &sk->sk_frag; 2609 } 2610 2611 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); 2612 2613 /* 2614 * Default write policy as shown to user space via poll/select/SIGIO 2615 */ 2616 static inline bool sock_writeable(const struct sock *sk) 2617 { 2618 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1); 2619 } 2620 2621 static inline gfp_t gfp_any(void) 2622 { 2623 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2624 } 2625 2626 static inline gfp_t gfp_memcg_charge(void) 2627 { 2628 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2629 } 2630 2631 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2632 { 2633 return noblock ? 0 : sk->sk_rcvtimeo; 2634 } 2635 2636 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2637 { 2638 return noblock ? 0 : sk->sk_sndtimeo; 2639 } 2640 2641 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2642 { 2643 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len); 2644 2645 return v ?: 1; 2646 } 2647 2648 /* Alas, with timeout socket operations are not restartable. 2649 * Compare this to poll(). 2650 */ 2651 static inline int sock_intr_errno(long timeo) 2652 { 2653 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2654 } 2655 2656 struct sock_skb_cb { 2657 u32 dropcount; 2658 }; 2659 2660 /* Store sock_skb_cb at the end of skb->cb[] so protocol families 2661 * using skb->cb[] would keep using it directly and utilize its 2662 * alignement guarantee. 2663 */ 2664 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \ 2665 sizeof(struct sock_skb_cb))) 2666 2667 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \ 2668 SOCK_SKB_CB_OFFSET)) 2669 2670 #define sock_skb_cb_check_size(size) \ 2671 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET) 2672 2673 static inline void 2674 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) 2675 { 2676 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? 2677 atomic_read(&sk->sk_drops) : 0; 2678 } 2679 2680 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) 2681 { 2682 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); 2683 2684 atomic_add(segs, &sk->sk_drops); 2685 } 2686 2687 static inline ktime_t sock_read_timestamp(struct sock *sk) 2688 { 2689 #if BITS_PER_LONG==32 2690 unsigned int seq; 2691 ktime_t kt; 2692 2693 do { 2694 seq = read_seqbegin(&sk->sk_stamp_seq); 2695 kt = sk->sk_stamp; 2696 } while (read_seqretry(&sk->sk_stamp_seq, seq)); 2697 2698 return kt; 2699 #else 2700 return READ_ONCE(sk->sk_stamp); 2701 #endif 2702 } 2703 2704 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt) 2705 { 2706 #if BITS_PER_LONG==32 2707 write_seqlock(&sk->sk_stamp_seq); 2708 sk->sk_stamp = kt; 2709 write_sequnlock(&sk->sk_stamp_seq); 2710 #else 2711 WRITE_ONCE(sk->sk_stamp, kt); 2712 #endif 2713 } 2714 2715 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2716 struct sk_buff *skb); 2717 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2718 struct sk_buff *skb); 2719 2720 static inline void 2721 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2722 { 2723 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2724 u32 tsflags = READ_ONCE(sk->sk_tsflags); 2725 ktime_t kt = skb->tstamp; 2726 /* 2727 * generate control messages if 2728 * - receive time stamping in software requested 2729 * - software time stamp available and wanted 2730 * - hardware time stamps available and wanted 2731 */ 2732 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2733 (tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) || 2734 (kt && tsflags & SOF_TIMESTAMPING_SOFTWARE) || 2735 (hwtstamps->hwtstamp && 2736 (tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))) 2737 __sock_recv_timestamp(msg, sk, skb); 2738 else 2739 sock_write_timestamp(sk, kt); 2740 2741 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb)) 2742 __sock_recv_wifi_status(msg, sk, skb); 2743 } 2744 2745 void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk, 2746 struct sk_buff *skb); 2747 2748 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC) 2749 static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk, 2750 struct sk_buff *skb) 2751 { 2752 #define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL) | \ 2753 (1UL << SOCK_RCVTSTAMP) | \ 2754 (1UL << SOCK_RCVMARK)) 2755 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \ 2756 SOF_TIMESTAMPING_RAW_HARDWARE) 2757 2758 if (sk->sk_flags & FLAGS_RECV_CMSGS || 2759 READ_ONCE(sk->sk_tsflags) & TSFLAGS_ANY) 2760 __sock_recv_cmsgs(msg, sk, skb); 2761 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP))) 2762 sock_write_timestamp(sk, skb->tstamp); 2763 else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP)) 2764 sock_write_timestamp(sk, 0); 2765 } 2766 2767 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags); 2768 2769 /** 2770 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2771 * @sk: socket sending this packet 2772 * @tsflags: timestamping flags to use 2773 * @tx_flags: completed with instructions for time stamping 2774 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno) 2775 * 2776 * Note: callers should take care of initial ``*tx_flags`` value (usually 0) 2777 */ 2778 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2779 __u8 *tx_flags, __u32 *tskey) 2780 { 2781 if (unlikely(tsflags)) { 2782 __sock_tx_timestamp(tsflags, tx_flags); 2783 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey && 2784 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) 2785 *tskey = atomic_inc_return(&sk->sk_tskey) - 1; 2786 } 2787 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS))) 2788 *tx_flags |= SKBTX_WIFI_STATUS; 2789 } 2790 2791 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2792 __u8 *tx_flags) 2793 { 2794 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL); 2795 } 2796 2797 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) 2798 { 2799 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags, 2800 &skb_shinfo(skb)->tskey); 2801 } 2802 2803 static inline bool sk_is_inet(const struct sock *sk) 2804 { 2805 int family = READ_ONCE(sk->sk_family); 2806 2807 return family == AF_INET || family == AF_INET6; 2808 } 2809 2810 static inline bool sk_is_tcp(const struct sock *sk) 2811 { 2812 return sk_is_inet(sk) && 2813 sk->sk_type == SOCK_STREAM && 2814 sk->sk_protocol == IPPROTO_TCP; 2815 } 2816 2817 static inline bool sk_is_udp(const struct sock *sk) 2818 { 2819 return sk_is_inet(sk) && 2820 sk->sk_type == SOCK_DGRAM && 2821 sk->sk_protocol == IPPROTO_UDP; 2822 } 2823 2824 static inline bool sk_is_stream_unix(const struct sock *sk) 2825 { 2826 return sk->sk_family == AF_UNIX && sk->sk_type == SOCK_STREAM; 2827 } 2828 2829 static inline bool sk_is_vsock(const struct sock *sk) 2830 { 2831 return sk->sk_family == AF_VSOCK; 2832 } 2833 2834 /** 2835 * sk_eat_skb - Release a skb if it is no longer needed 2836 * @sk: socket to eat this skb from 2837 * @skb: socket buffer to eat 2838 * 2839 * This routine must be called with interrupts disabled or with the socket 2840 * locked so that the sk_buff queue operation is ok. 2841 */ 2842 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) 2843 { 2844 __skb_unlink(skb, &sk->sk_receive_queue); 2845 __kfree_skb(skb); 2846 } 2847 2848 static inline bool 2849 skb_sk_is_prefetched(struct sk_buff *skb) 2850 { 2851 #ifdef CONFIG_INET 2852 return skb->destructor == sock_pfree; 2853 #else 2854 return false; 2855 #endif /* CONFIG_INET */ 2856 } 2857 2858 /* This helper checks if a socket is a full socket, 2859 * ie _not_ a timewait or request socket. 2860 */ 2861 static inline bool sk_fullsock(const struct sock *sk) 2862 { 2863 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV); 2864 } 2865 2866 static inline bool 2867 sk_is_refcounted(struct sock *sk) 2868 { 2869 /* Only full sockets have sk->sk_flags. */ 2870 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE); 2871 } 2872 2873 /** 2874 * skb_steal_sock - steal a socket from an sk_buff 2875 * @skb: sk_buff to steal the socket from 2876 * @refcounted: is set to true if the socket is reference-counted 2877 * @prefetched: is set to true if the socket was assigned from bpf 2878 */ 2879 static inline struct sock * 2880 skb_steal_sock(struct sk_buff *skb, bool *refcounted, bool *prefetched) 2881 { 2882 if (skb->sk) { 2883 struct sock *sk = skb->sk; 2884 2885 *refcounted = true; 2886 *prefetched = skb_sk_is_prefetched(skb); 2887 if (*prefetched) 2888 *refcounted = sk_is_refcounted(sk); 2889 skb->destructor = NULL; 2890 skb->sk = NULL; 2891 return sk; 2892 } 2893 *prefetched = false; 2894 *refcounted = false; 2895 return NULL; 2896 } 2897 2898 /* Checks if this SKB belongs to an HW offloaded socket 2899 * and whether any SW fallbacks are required based on dev. 2900 * Check decrypted mark in case skb_orphan() cleared socket. 2901 */ 2902 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, 2903 struct net_device *dev) 2904 { 2905 #ifdef CONFIG_SOCK_VALIDATE_XMIT 2906 struct sock *sk = skb->sk; 2907 2908 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) { 2909 skb = sk->sk_validate_xmit_skb(sk, dev, skb); 2910 #ifdef CONFIG_TLS_DEVICE 2911 } else if (unlikely(skb->decrypted)) { 2912 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n"); 2913 kfree_skb(skb); 2914 skb = NULL; 2915 #endif 2916 } 2917 #endif 2918 2919 return skb; 2920 } 2921 2922 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV 2923 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE) 2924 */ 2925 static inline bool sk_listener(const struct sock *sk) 2926 { 2927 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV); 2928 } 2929 2930 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag); 2931 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level, 2932 int type); 2933 2934 bool sk_ns_capable(const struct sock *sk, 2935 struct user_namespace *user_ns, int cap); 2936 bool sk_capable(const struct sock *sk, int cap); 2937 bool sk_net_capable(const struct sock *sk, int cap); 2938 2939 void sk_get_meminfo(const struct sock *sk, u32 *meminfo); 2940 2941 /* Take into consideration the size of the struct sk_buff overhead in the 2942 * determination of these values, since that is non-constant across 2943 * platforms. This makes socket queueing behavior and performance 2944 * not depend upon such differences. 2945 */ 2946 #define _SK_MEM_PACKETS 256 2947 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 2948 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2949 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2950 2951 extern __u32 sysctl_wmem_max; 2952 extern __u32 sysctl_rmem_max; 2953 2954 extern int sysctl_tstamp_allow_data; 2955 extern int sysctl_optmem_max; 2956 2957 extern __u32 sysctl_wmem_default; 2958 extern __u32 sysctl_rmem_default; 2959 2960 #define SKB_FRAG_PAGE_ORDER get_order(32768) 2961 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2962 2963 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) 2964 { 2965 /* Does this proto have per netns sysctl_wmem ? */ 2966 if (proto->sysctl_wmem_offset) 2967 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset)); 2968 2969 return READ_ONCE(*proto->sysctl_wmem); 2970 } 2971 2972 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) 2973 { 2974 /* Does this proto have per netns sysctl_rmem ? */ 2975 if (proto->sysctl_rmem_offset) 2976 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset)); 2977 2978 return READ_ONCE(*proto->sysctl_rmem); 2979 } 2980 2981 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) 2982 * Some wifi drivers need to tweak it to get more chunks. 2983 * They can use this helper from their ndo_start_xmit() 2984 */ 2985 static inline void sk_pacing_shift_update(struct sock *sk, int val) 2986 { 2987 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val) 2988 return; 2989 WRITE_ONCE(sk->sk_pacing_shift, val); 2990 } 2991 2992 /* if a socket is bound to a device, check that the given device 2993 * index is either the same or that the socket is bound to an L3 2994 * master device and the given device index is also enslaved to 2995 * that L3 master 2996 */ 2997 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif) 2998 { 2999 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); 3000 int mdif; 3001 3002 if (!bound_dev_if || bound_dev_if == dif) 3003 return true; 3004 3005 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif); 3006 if (mdif && mdif == bound_dev_if) 3007 return true; 3008 3009 return false; 3010 } 3011 3012 void sock_def_readable(struct sock *sk); 3013 3014 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk); 3015 void sock_set_timestamp(struct sock *sk, int optname, bool valbool); 3016 int sock_set_timestamping(struct sock *sk, int optname, 3017 struct so_timestamping timestamping); 3018 3019 void sock_enable_timestamps(struct sock *sk); 3020 void sock_no_linger(struct sock *sk); 3021 void sock_set_keepalive(struct sock *sk); 3022 void sock_set_priority(struct sock *sk, u32 priority); 3023 void sock_set_rcvbuf(struct sock *sk, int val); 3024 void sock_set_mark(struct sock *sk, u32 val); 3025 void sock_set_reuseaddr(struct sock *sk); 3026 void sock_set_reuseport(struct sock *sk); 3027 void sock_set_sndtimeo(struct sock *sk, s64 secs); 3028 3029 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len); 3030 3031 int sock_get_timeout(long timeo, void *optval, bool old_timeval); 3032 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv, 3033 sockptr_t optval, int optlen, bool old_timeval); 3034 3035 int sock_ioctl_inout(struct sock *sk, unsigned int cmd, 3036 void __user *arg, void *karg, size_t size); 3037 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg); 3038 static inline bool sk_is_readable(struct sock *sk) 3039 { 3040 if (sk->sk_prot->sock_is_readable) 3041 return sk->sk_prot->sock_is_readable(sk); 3042 return false; 3043 } 3044 #endif /* _SOCK_H */ 3045