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_wait_pending: number of threads blocked on this socket 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_wait_pending; 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) 905 906 /** 907 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset 908 * @tpos: the type * to use as a loop cursor. 909 * @pos: the &struct hlist_node to use as a loop cursor. 910 * @head: the head for your list. 911 * @offset: offset of hlist_node within the struct. 912 * 913 */ 914 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \ 915 for (pos = rcu_dereference(hlist_first_rcu(head)); \ 916 pos != NULL && \ 917 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \ 918 pos = rcu_dereference(hlist_next_rcu(pos))) 919 920 static inline struct user_namespace *sk_user_ns(const struct sock *sk) 921 { 922 /* Careful only use this in a context where these parameters 923 * can not change and must all be valid, such as recvmsg from 924 * userspace. 925 */ 926 return sk->sk_socket->file->f_cred->user_ns; 927 } 928 929 /* Sock flags */ 930 enum sock_flags { 931 SOCK_DEAD, 932 SOCK_DONE, 933 SOCK_URGINLINE, 934 SOCK_KEEPOPEN, 935 SOCK_LINGER, 936 SOCK_DESTROY, 937 SOCK_BROADCAST, 938 SOCK_TIMESTAMP, 939 SOCK_ZAPPED, 940 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */ 941 SOCK_DBG, /* %SO_DEBUG setting */ 942 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */ 943 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */ 944 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */ 945 SOCK_MEMALLOC, /* VM depends on this socket for swapping */ 946 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */ 947 SOCK_FASYNC, /* fasync() active */ 948 SOCK_RXQ_OVFL, 949 SOCK_ZEROCOPY, /* buffers from userspace */ 950 SOCK_WIFI_STATUS, /* push wifi status to userspace */ 951 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS. 952 * Will use last 4 bytes of packet sent from 953 * user-space instead. 954 */ 955 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */ 956 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */ 957 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */ 958 SOCK_TXTIME, 959 SOCK_XDP, /* XDP is attached */ 960 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */ 961 SOCK_RCVMARK, /* Receive SO_MARK ancillary data with packet */ 962 }; 963 964 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE)) 965 966 static inline void sock_copy_flags(struct sock *nsk, const struct sock *osk) 967 { 968 nsk->sk_flags = osk->sk_flags; 969 } 970 971 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag) 972 { 973 __set_bit(flag, &sk->sk_flags); 974 } 975 976 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag) 977 { 978 __clear_bit(flag, &sk->sk_flags); 979 } 980 981 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit, 982 int valbool) 983 { 984 if (valbool) 985 sock_set_flag(sk, bit); 986 else 987 sock_reset_flag(sk, bit); 988 } 989 990 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag) 991 { 992 return test_bit(flag, &sk->sk_flags); 993 } 994 995 #ifdef CONFIG_NET 996 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key); 997 static inline int sk_memalloc_socks(void) 998 { 999 return static_branch_unlikely(&memalloc_socks_key); 1000 } 1001 1002 void __receive_sock(struct file *file); 1003 #else 1004 1005 static inline int sk_memalloc_socks(void) 1006 { 1007 return 0; 1008 } 1009 1010 static inline void __receive_sock(struct file *file) 1011 { } 1012 #endif 1013 1014 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask) 1015 { 1016 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC); 1017 } 1018 1019 static inline void sk_acceptq_removed(struct sock *sk) 1020 { 1021 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1); 1022 } 1023 1024 static inline void sk_acceptq_added(struct sock *sk) 1025 { 1026 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1); 1027 } 1028 1029 /* Note: If you think the test should be: 1030 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog); 1031 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.") 1032 */ 1033 static inline bool sk_acceptq_is_full(const struct sock *sk) 1034 { 1035 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog); 1036 } 1037 1038 /* 1039 * Compute minimal free write space needed to queue new packets. 1040 */ 1041 static inline int sk_stream_min_wspace(const struct sock *sk) 1042 { 1043 return READ_ONCE(sk->sk_wmem_queued) >> 1; 1044 } 1045 1046 static inline int sk_stream_wspace(const struct sock *sk) 1047 { 1048 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued); 1049 } 1050 1051 static inline void sk_wmem_queued_add(struct sock *sk, int val) 1052 { 1053 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val); 1054 } 1055 1056 void sk_stream_write_space(struct sock *sk); 1057 1058 /* OOB backlog add */ 1059 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb) 1060 { 1061 /* dont let skb dst not refcounted, we are going to leave rcu lock */ 1062 skb_dst_force(skb); 1063 1064 if (!sk->sk_backlog.tail) 1065 WRITE_ONCE(sk->sk_backlog.head, skb); 1066 else 1067 sk->sk_backlog.tail->next = skb; 1068 1069 WRITE_ONCE(sk->sk_backlog.tail, skb); 1070 skb->next = NULL; 1071 } 1072 1073 /* 1074 * Take into account size of receive queue and backlog queue 1075 * Do not take into account this skb truesize, 1076 * to allow even a single big packet to come. 1077 */ 1078 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit) 1079 { 1080 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc); 1081 1082 return qsize > limit; 1083 } 1084 1085 /* The per-socket spinlock must be held here. */ 1086 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb, 1087 unsigned int limit) 1088 { 1089 if (sk_rcvqueues_full(sk, limit)) 1090 return -ENOBUFS; 1091 1092 /* 1093 * If the skb was allocated from pfmemalloc reserves, only 1094 * allow SOCK_MEMALLOC sockets to use it as this socket is 1095 * helping free memory 1096 */ 1097 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) 1098 return -ENOMEM; 1099 1100 __sk_add_backlog(sk, skb); 1101 sk->sk_backlog.len += skb->truesize; 1102 return 0; 1103 } 1104 1105 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb); 1106 1107 INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)); 1108 INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)); 1109 1110 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb) 1111 { 1112 if (sk_memalloc_socks() && skb_pfmemalloc(skb)) 1113 return __sk_backlog_rcv(sk, skb); 1114 1115 return INDIRECT_CALL_INET(sk->sk_backlog_rcv, 1116 tcp_v6_do_rcv, 1117 tcp_v4_do_rcv, 1118 sk, skb); 1119 } 1120 1121 static inline void sk_incoming_cpu_update(struct sock *sk) 1122 { 1123 int cpu = raw_smp_processor_id(); 1124 1125 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu)) 1126 WRITE_ONCE(sk->sk_incoming_cpu, cpu); 1127 } 1128 1129 static inline void sock_rps_record_flow_hash(__u32 hash) 1130 { 1131 #ifdef CONFIG_RPS 1132 struct rps_sock_flow_table *sock_flow_table; 1133 1134 rcu_read_lock(); 1135 sock_flow_table = rcu_dereference(rps_sock_flow_table); 1136 rps_record_sock_flow(sock_flow_table, hash); 1137 rcu_read_unlock(); 1138 #endif 1139 } 1140 1141 static inline void sock_rps_record_flow(const struct sock *sk) 1142 { 1143 #ifdef CONFIG_RPS 1144 if (static_branch_unlikely(&rfs_needed)) { 1145 /* Reading sk->sk_rxhash might incur an expensive cache line 1146 * miss. 1147 * 1148 * TCP_ESTABLISHED does cover almost all states where RFS 1149 * might be useful, and is cheaper [1] than testing : 1150 * IPv4: inet_sk(sk)->inet_daddr 1151 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr) 1152 * OR an additional socket flag 1153 * [1] : sk_state and sk_prot are in the same cache line. 1154 */ 1155 if (sk->sk_state == TCP_ESTABLISHED) { 1156 /* This READ_ONCE() is paired with the WRITE_ONCE() 1157 * from sock_rps_save_rxhash() and sock_rps_reset_rxhash(). 1158 */ 1159 sock_rps_record_flow_hash(READ_ONCE(sk->sk_rxhash)); 1160 } 1161 } 1162 #endif 1163 } 1164 1165 static inline void sock_rps_save_rxhash(struct sock *sk, 1166 const struct sk_buff *skb) 1167 { 1168 #ifdef CONFIG_RPS 1169 /* The following WRITE_ONCE() is paired with the READ_ONCE() 1170 * here, and another one in sock_rps_record_flow(). 1171 */ 1172 if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash)) 1173 WRITE_ONCE(sk->sk_rxhash, skb->hash); 1174 #endif 1175 } 1176 1177 static inline void sock_rps_reset_rxhash(struct sock *sk) 1178 { 1179 #ifdef CONFIG_RPS 1180 /* Paired with READ_ONCE() in sock_rps_record_flow() */ 1181 WRITE_ONCE(sk->sk_rxhash, 0); 1182 #endif 1183 } 1184 1185 #define sk_wait_event(__sk, __timeo, __condition, __wait) \ 1186 ({ int __rc; \ 1187 __sk->sk_wait_pending++; \ 1188 release_sock(__sk); \ 1189 __rc = __condition; \ 1190 if (!__rc) { \ 1191 *(__timeo) = wait_woken(__wait, \ 1192 TASK_INTERRUPTIBLE, \ 1193 *(__timeo)); \ 1194 } \ 1195 sched_annotate_sleep(); \ 1196 lock_sock(__sk); \ 1197 __sk->sk_wait_pending--; \ 1198 __rc = __condition; \ 1199 __rc; \ 1200 }) 1201 1202 int sk_stream_wait_connect(struct sock *sk, long *timeo_p); 1203 int sk_stream_wait_memory(struct sock *sk, long *timeo_p); 1204 void sk_stream_wait_close(struct sock *sk, long timeo_p); 1205 int sk_stream_error(struct sock *sk, int flags, int err); 1206 void sk_stream_kill_queues(struct sock *sk); 1207 void sk_set_memalloc(struct sock *sk); 1208 void sk_clear_memalloc(struct sock *sk); 1209 1210 void __sk_flush_backlog(struct sock *sk); 1211 1212 static inline bool sk_flush_backlog(struct sock *sk) 1213 { 1214 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) { 1215 __sk_flush_backlog(sk); 1216 return true; 1217 } 1218 return false; 1219 } 1220 1221 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb); 1222 1223 struct request_sock_ops; 1224 struct timewait_sock_ops; 1225 struct inet_hashinfo; 1226 struct raw_hashinfo; 1227 struct smc_hashinfo; 1228 struct module; 1229 struct sk_psock; 1230 1231 /* 1232 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes 1233 * un-modified. Special care is taken when initializing object to zero. 1234 */ 1235 static inline void sk_prot_clear_nulls(struct sock *sk, int size) 1236 { 1237 if (offsetof(struct sock, sk_node.next) != 0) 1238 memset(sk, 0, offsetof(struct sock, sk_node.next)); 1239 memset(&sk->sk_node.pprev, 0, 1240 size - offsetof(struct sock, sk_node.pprev)); 1241 } 1242 1243 /* Networking protocol blocks we attach to sockets. 1244 * socket layer -> transport layer interface 1245 */ 1246 struct proto { 1247 void (*close)(struct sock *sk, 1248 long timeout); 1249 int (*pre_connect)(struct sock *sk, 1250 struct sockaddr *uaddr, 1251 int addr_len); 1252 int (*connect)(struct sock *sk, 1253 struct sockaddr *uaddr, 1254 int addr_len); 1255 int (*disconnect)(struct sock *sk, int flags); 1256 1257 struct sock * (*accept)(struct sock *sk, int flags, int *err, 1258 bool kern); 1259 1260 int (*ioctl)(struct sock *sk, int cmd, 1261 int *karg); 1262 int (*init)(struct sock *sk); 1263 void (*destroy)(struct sock *sk); 1264 void (*shutdown)(struct sock *sk, int how); 1265 int (*setsockopt)(struct sock *sk, int level, 1266 int optname, sockptr_t optval, 1267 unsigned int optlen); 1268 int (*getsockopt)(struct sock *sk, int level, 1269 int optname, char __user *optval, 1270 int __user *option); 1271 void (*keepalive)(struct sock *sk, int valbool); 1272 #ifdef CONFIG_COMPAT 1273 int (*compat_ioctl)(struct sock *sk, 1274 unsigned int cmd, unsigned long arg); 1275 #endif 1276 int (*sendmsg)(struct sock *sk, struct msghdr *msg, 1277 size_t len); 1278 int (*recvmsg)(struct sock *sk, struct msghdr *msg, 1279 size_t len, int flags, int *addr_len); 1280 void (*splice_eof)(struct socket *sock); 1281 int (*bind)(struct sock *sk, 1282 struct sockaddr *addr, int addr_len); 1283 int (*bind_add)(struct sock *sk, 1284 struct sockaddr *addr, int addr_len); 1285 1286 int (*backlog_rcv) (struct sock *sk, 1287 struct sk_buff *skb); 1288 bool (*bpf_bypass_getsockopt)(int level, 1289 int optname); 1290 1291 void (*release_cb)(struct sock *sk); 1292 1293 /* Keeping track of sk's, looking them up, and port selection methods. */ 1294 int (*hash)(struct sock *sk); 1295 void (*unhash)(struct sock *sk); 1296 void (*rehash)(struct sock *sk); 1297 int (*get_port)(struct sock *sk, unsigned short snum); 1298 void (*put_port)(struct sock *sk); 1299 #ifdef CONFIG_BPF_SYSCALL 1300 int (*psock_update_sk_prot)(struct sock *sk, 1301 struct sk_psock *psock, 1302 bool restore); 1303 #endif 1304 1305 /* Keeping track of sockets in use */ 1306 #ifdef CONFIG_PROC_FS 1307 unsigned int inuse_idx; 1308 #endif 1309 1310 #if IS_ENABLED(CONFIG_MPTCP) 1311 int (*forward_alloc_get)(const struct sock *sk); 1312 #endif 1313 1314 bool (*stream_memory_free)(const struct sock *sk, int wake); 1315 bool (*sock_is_readable)(struct sock *sk); 1316 /* Memory pressure */ 1317 void (*enter_memory_pressure)(struct sock *sk); 1318 void (*leave_memory_pressure)(struct sock *sk); 1319 atomic_long_t *memory_allocated; /* Current allocated memory. */ 1320 int __percpu *per_cpu_fw_alloc; 1321 struct percpu_counter *sockets_allocated; /* Current number of sockets. */ 1322 1323 /* 1324 * Pressure flag: try to collapse. 1325 * Technical note: it is used by multiple contexts non atomically. 1326 * All the __sk_mem_schedule() is of this nature: accounting 1327 * is strict, actions are advisory and have some latency. 1328 */ 1329 unsigned long *memory_pressure; 1330 long *sysctl_mem; 1331 1332 int *sysctl_wmem; 1333 int *sysctl_rmem; 1334 u32 sysctl_wmem_offset; 1335 u32 sysctl_rmem_offset; 1336 1337 int max_header; 1338 bool no_autobind; 1339 1340 struct kmem_cache *slab; 1341 unsigned int obj_size; 1342 slab_flags_t slab_flags; 1343 unsigned int useroffset; /* Usercopy region offset */ 1344 unsigned int usersize; /* Usercopy region size */ 1345 1346 unsigned int __percpu *orphan_count; 1347 1348 struct request_sock_ops *rsk_prot; 1349 struct timewait_sock_ops *twsk_prot; 1350 1351 union { 1352 struct inet_hashinfo *hashinfo; 1353 struct udp_table *udp_table; 1354 struct raw_hashinfo *raw_hash; 1355 struct smc_hashinfo *smc_hash; 1356 } h; 1357 1358 struct module *owner; 1359 1360 char name[32]; 1361 1362 struct list_head node; 1363 int (*diag_destroy)(struct sock *sk, int err); 1364 } __randomize_layout; 1365 1366 int proto_register(struct proto *prot, int alloc_slab); 1367 void proto_unregister(struct proto *prot); 1368 int sock_load_diag_module(int family, int protocol); 1369 1370 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake)); 1371 1372 static inline int sk_forward_alloc_get(const struct sock *sk) 1373 { 1374 #if IS_ENABLED(CONFIG_MPTCP) 1375 if (sk->sk_prot->forward_alloc_get) 1376 return sk->sk_prot->forward_alloc_get(sk); 1377 #endif 1378 return sk->sk_forward_alloc; 1379 } 1380 1381 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake) 1382 { 1383 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf)) 1384 return false; 1385 1386 return sk->sk_prot->stream_memory_free ? 1387 INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free, 1388 tcp_stream_memory_free, sk, wake) : true; 1389 } 1390 1391 static inline bool sk_stream_memory_free(const struct sock *sk) 1392 { 1393 return __sk_stream_memory_free(sk, 0); 1394 } 1395 1396 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake) 1397 { 1398 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) && 1399 __sk_stream_memory_free(sk, wake); 1400 } 1401 1402 static inline bool sk_stream_is_writeable(const struct sock *sk) 1403 { 1404 return __sk_stream_is_writeable(sk, 0); 1405 } 1406 1407 static inline int sk_under_cgroup_hierarchy(struct sock *sk, 1408 struct cgroup *ancestor) 1409 { 1410 #ifdef CONFIG_SOCK_CGROUP_DATA 1411 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data), 1412 ancestor); 1413 #else 1414 return -ENOTSUPP; 1415 #endif 1416 } 1417 1418 static inline bool sk_has_memory_pressure(const struct sock *sk) 1419 { 1420 return sk->sk_prot->memory_pressure != NULL; 1421 } 1422 1423 static inline bool sk_under_global_memory_pressure(const struct sock *sk) 1424 { 1425 return sk->sk_prot->memory_pressure && 1426 !!*sk->sk_prot->memory_pressure; 1427 } 1428 1429 static inline bool sk_under_memory_pressure(const struct sock *sk) 1430 { 1431 if (!sk->sk_prot->memory_pressure) 1432 return false; 1433 1434 if (mem_cgroup_sockets_enabled && sk->sk_memcg && 1435 mem_cgroup_under_socket_pressure(sk->sk_memcg)) 1436 return true; 1437 1438 return !!*sk->sk_prot->memory_pressure; 1439 } 1440 1441 static inline long 1442 proto_memory_allocated(const struct proto *prot) 1443 { 1444 return max(0L, atomic_long_read(prot->memory_allocated)); 1445 } 1446 1447 static inline long 1448 sk_memory_allocated(const struct sock *sk) 1449 { 1450 return proto_memory_allocated(sk->sk_prot); 1451 } 1452 1453 /* 1 MB per cpu, in page units */ 1454 #define SK_MEMORY_PCPU_RESERVE (1 << (20 - PAGE_SHIFT)) 1455 1456 static inline void 1457 sk_memory_allocated_add(struct sock *sk, int amt) 1458 { 1459 int local_reserve; 1460 1461 preempt_disable(); 1462 local_reserve = __this_cpu_add_return(*sk->sk_prot->per_cpu_fw_alloc, amt); 1463 if (local_reserve >= SK_MEMORY_PCPU_RESERVE) { 1464 __this_cpu_sub(*sk->sk_prot->per_cpu_fw_alloc, local_reserve); 1465 atomic_long_add(local_reserve, sk->sk_prot->memory_allocated); 1466 } 1467 preempt_enable(); 1468 } 1469 1470 static inline void 1471 sk_memory_allocated_sub(struct sock *sk, int amt) 1472 { 1473 int local_reserve; 1474 1475 preempt_disable(); 1476 local_reserve = __this_cpu_sub_return(*sk->sk_prot->per_cpu_fw_alloc, amt); 1477 if (local_reserve <= -SK_MEMORY_PCPU_RESERVE) { 1478 __this_cpu_sub(*sk->sk_prot->per_cpu_fw_alloc, local_reserve); 1479 atomic_long_add(local_reserve, sk->sk_prot->memory_allocated); 1480 } 1481 preempt_enable(); 1482 } 1483 1484 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16 1485 1486 static inline void sk_sockets_allocated_dec(struct sock *sk) 1487 { 1488 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1, 1489 SK_ALLOC_PERCPU_COUNTER_BATCH); 1490 } 1491 1492 static inline void sk_sockets_allocated_inc(struct sock *sk) 1493 { 1494 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1, 1495 SK_ALLOC_PERCPU_COUNTER_BATCH); 1496 } 1497 1498 static inline u64 1499 sk_sockets_allocated_read_positive(struct sock *sk) 1500 { 1501 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated); 1502 } 1503 1504 static inline int 1505 proto_sockets_allocated_sum_positive(struct proto *prot) 1506 { 1507 return percpu_counter_sum_positive(prot->sockets_allocated); 1508 } 1509 1510 static inline bool 1511 proto_memory_pressure(struct proto *prot) 1512 { 1513 if (!prot->memory_pressure) 1514 return false; 1515 return !!*prot->memory_pressure; 1516 } 1517 1518 1519 #ifdef CONFIG_PROC_FS 1520 #define PROTO_INUSE_NR 64 /* should be enough for the first time */ 1521 struct prot_inuse { 1522 int all; 1523 int val[PROTO_INUSE_NR]; 1524 }; 1525 1526 static inline void sock_prot_inuse_add(const struct net *net, 1527 const struct proto *prot, int val) 1528 { 1529 this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val); 1530 } 1531 1532 static inline void sock_inuse_add(const struct net *net, int val) 1533 { 1534 this_cpu_add(net->core.prot_inuse->all, val); 1535 } 1536 1537 int sock_prot_inuse_get(struct net *net, struct proto *proto); 1538 int sock_inuse_get(struct net *net); 1539 #else 1540 static inline void sock_prot_inuse_add(const struct net *net, 1541 const struct proto *prot, int val) 1542 { 1543 } 1544 1545 static inline void sock_inuse_add(const struct net *net, int val) 1546 { 1547 } 1548 #endif 1549 1550 1551 /* With per-bucket locks this operation is not-atomic, so that 1552 * this version is not worse. 1553 */ 1554 static inline int __sk_prot_rehash(struct sock *sk) 1555 { 1556 sk->sk_prot->unhash(sk); 1557 return sk->sk_prot->hash(sk); 1558 } 1559 1560 /* About 10 seconds */ 1561 #define SOCK_DESTROY_TIME (10*HZ) 1562 1563 /* Sockets 0-1023 can't be bound to unless you are superuser */ 1564 #define PROT_SOCK 1024 1565 1566 #define SHUTDOWN_MASK 3 1567 #define RCV_SHUTDOWN 1 1568 #define SEND_SHUTDOWN 2 1569 1570 #define SOCK_BINDADDR_LOCK 4 1571 #define SOCK_BINDPORT_LOCK 8 1572 1573 struct socket_alloc { 1574 struct socket socket; 1575 struct inode vfs_inode; 1576 }; 1577 1578 static inline struct socket *SOCKET_I(struct inode *inode) 1579 { 1580 return &container_of(inode, struct socket_alloc, vfs_inode)->socket; 1581 } 1582 1583 static inline struct inode *SOCK_INODE(struct socket *socket) 1584 { 1585 return &container_of(socket, struct socket_alloc, socket)->vfs_inode; 1586 } 1587 1588 /* 1589 * Functions for memory accounting 1590 */ 1591 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind); 1592 int __sk_mem_schedule(struct sock *sk, int size, int kind); 1593 void __sk_mem_reduce_allocated(struct sock *sk, int amount); 1594 void __sk_mem_reclaim(struct sock *sk, int amount); 1595 1596 #define SK_MEM_SEND 0 1597 #define SK_MEM_RECV 1 1598 1599 /* sysctl_mem values are in pages */ 1600 static inline long sk_prot_mem_limits(const struct sock *sk, int index) 1601 { 1602 return READ_ONCE(sk->sk_prot->sysctl_mem[index]); 1603 } 1604 1605 static inline int sk_mem_pages(int amt) 1606 { 1607 return (amt + PAGE_SIZE - 1) >> PAGE_SHIFT; 1608 } 1609 1610 static inline bool sk_has_account(struct sock *sk) 1611 { 1612 /* return true if protocol supports memory accounting */ 1613 return !!sk->sk_prot->memory_allocated; 1614 } 1615 1616 static inline bool sk_wmem_schedule(struct sock *sk, int size) 1617 { 1618 int delta; 1619 1620 if (!sk_has_account(sk)) 1621 return true; 1622 delta = size - sk->sk_forward_alloc; 1623 return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND); 1624 } 1625 1626 static inline bool 1627 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, 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_RECV) || 1635 skb_pfmemalloc(skb); 1636 } 1637 1638 static inline int sk_unused_reserved_mem(const struct sock *sk) 1639 { 1640 int unused_mem; 1641 1642 if (likely(!sk->sk_reserved_mem)) 1643 return 0; 1644 1645 unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued - 1646 atomic_read(&sk->sk_rmem_alloc); 1647 1648 return unused_mem > 0 ? unused_mem : 0; 1649 } 1650 1651 static inline void sk_mem_reclaim(struct sock *sk) 1652 { 1653 int reclaimable; 1654 1655 if (!sk_has_account(sk)) 1656 return; 1657 1658 reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk); 1659 1660 if (reclaimable >= (int)PAGE_SIZE) 1661 __sk_mem_reclaim(sk, reclaimable); 1662 } 1663 1664 static inline void sk_mem_reclaim_final(struct sock *sk) 1665 { 1666 sk->sk_reserved_mem = 0; 1667 sk_mem_reclaim(sk); 1668 } 1669 1670 static inline void sk_mem_charge(struct sock *sk, int size) 1671 { 1672 if (!sk_has_account(sk)) 1673 return; 1674 sk->sk_forward_alloc -= size; 1675 } 1676 1677 static inline void sk_mem_uncharge(struct sock *sk, int size) 1678 { 1679 if (!sk_has_account(sk)) 1680 return; 1681 sk->sk_forward_alloc += size; 1682 sk_mem_reclaim(sk); 1683 } 1684 1685 /* 1686 * Macro so as to not evaluate some arguments when 1687 * lockdep is not enabled. 1688 * 1689 * Mark both the sk_lock and the sk_lock.slock as a 1690 * per-address-family lock class. 1691 */ 1692 #define sock_lock_init_class_and_name(sk, sname, skey, name, key) \ 1693 do { \ 1694 sk->sk_lock.owned = 0; \ 1695 init_waitqueue_head(&sk->sk_lock.wq); \ 1696 spin_lock_init(&(sk)->sk_lock.slock); \ 1697 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \ 1698 sizeof((sk)->sk_lock)); \ 1699 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \ 1700 (skey), (sname)); \ 1701 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \ 1702 } while (0) 1703 1704 static inline bool lockdep_sock_is_held(const struct sock *sk) 1705 { 1706 return lockdep_is_held(&sk->sk_lock) || 1707 lockdep_is_held(&sk->sk_lock.slock); 1708 } 1709 1710 void lock_sock_nested(struct sock *sk, int subclass); 1711 1712 static inline void lock_sock(struct sock *sk) 1713 { 1714 lock_sock_nested(sk, 0); 1715 } 1716 1717 void __lock_sock(struct sock *sk); 1718 void __release_sock(struct sock *sk); 1719 void release_sock(struct sock *sk); 1720 1721 /* BH context may only use the following locking interface. */ 1722 #define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock)) 1723 #define bh_lock_sock_nested(__sk) \ 1724 spin_lock_nested(&((__sk)->sk_lock.slock), \ 1725 SINGLE_DEPTH_NESTING) 1726 #define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock)) 1727 1728 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock); 1729 1730 /** 1731 * lock_sock_fast - fast version of lock_sock 1732 * @sk: socket 1733 * 1734 * This version should be used for very small section, where process wont block 1735 * return false if fast path is taken: 1736 * 1737 * sk_lock.slock locked, owned = 0, BH disabled 1738 * 1739 * return true if slow path is taken: 1740 * 1741 * sk_lock.slock unlocked, owned = 1, BH enabled 1742 */ 1743 static inline bool lock_sock_fast(struct sock *sk) 1744 { 1745 /* The sk_lock has mutex_lock() semantics here. */ 1746 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); 1747 1748 return __lock_sock_fast(sk); 1749 } 1750 1751 /* fast socket lock variant for caller already holding a [different] socket lock */ 1752 static inline bool lock_sock_fast_nested(struct sock *sk) 1753 { 1754 mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_); 1755 1756 return __lock_sock_fast(sk); 1757 } 1758 1759 /** 1760 * unlock_sock_fast - complement of lock_sock_fast 1761 * @sk: socket 1762 * @slow: slow mode 1763 * 1764 * fast unlock socket for user context. 1765 * If slow mode is on, we call regular release_sock() 1766 */ 1767 static inline void unlock_sock_fast(struct sock *sk, bool slow) 1768 __releases(&sk->sk_lock.slock) 1769 { 1770 if (slow) { 1771 release_sock(sk); 1772 __release(&sk->sk_lock.slock); 1773 } else { 1774 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1775 spin_unlock_bh(&sk->sk_lock.slock); 1776 } 1777 } 1778 1779 void sockopt_lock_sock(struct sock *sk); 1780 void sockopt_release_sock(struct sock *sk); 1781 bool sockopt_ns_capable(struct user_namespace *ns, int cap); 1782 bool sockopt_capable(int cap); 1783 1784 /* Used by processes to "lock" a socket state, so that 1785 * interrupts and bottom half handlers won't change it 1786 * from under us. It essentially blocks any incoming 1787 * packets, so that we won't get any new data or any 1788 * packets that change the state of the socket. 1789 * 1790 * While locked, BH processing will add new packets to 1791 * the backlog queue. This queue is processed by the 1792 * owner of the socket lock right before it is released. 1793 * 1794 * Since ~2.3.5 it is also exclusive sleep lock serializing 1795 * accesses from user process context. 1796 */ 1797 1798 static inline void sock_owned_by_me(const struct sock *sk) 1799 { 1800 #ifdef CONFIG_LOCKDEP 1801 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks); 1802 #endif 1803 } 1804 1805 static inline bool sock_owned_by_user(const struct sock *sk) 1806 { 1807 sock_owned_by_me(sk); 1808 return sk->sk_lock.owned; 1809 } 1810 1811 static inline bool sock_owned_by_user_nocheck(const struct sock *sk) 1812 { 1813 return sk->sk_lock.owned; 1814 } 1815 1816 static inline void sock_release_ownership(struct sock *sk) 1817 { 1818 if (sock_owned_by_user_nocheck(sk)) { 1819 sk->sk_lock.owned = 0; 1820 1821 /* The sk_lock has mutex_unlock() semantics: */ 1822 mutex_release(&sk->sk_lock.dep_map, _RET_IP_); 1823 } 1824 } 1825 1826 /* no reclassification while locks are held */ 1827 static inline bool sock_allow_reclassification(const struct sock *csk) 1828 { 1829 struct sock *sk = (struct sock *)csk; 1830 1831 return !sock_owned_by_user_nocheck(sk) && 1832 !spin_is_locked(&sk->sk_lock.slock); 1833 } 1834 1835 struct sock *sk_alloc(struct net *net, int family, gfp_t priority, 1836 struct proto *prot, int kern); 1837 void sk_free(struct sock *sk); 1838 void sk_destruct(struct sock *sk); 1839 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority); 1840 void sk_free_unlock_clone(struct sock *sk); 1841 1842 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, 1843 gfp_t priority); 1844 void __sock_wfree(struct sk_buff *skb); 1845 void sock_wfree(struct sk_buff *skb); 1846 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size, 1847 gfp_t priority); 1848 void skb_orphan_partial(struct sk_buff *skb); 1849 void sock_rfree(struct sk_buff *skb); 1850 void sock_efree(struct sk_buff *skb); 1851 #ifdef CONFIG_INET 1852 void sock_edemux(struct sk_buff *skb); 1853 void sock_pfree(struct sk_buff *skb); 1854 #else 1855 #define sock_edemux sock_efree 1856 #endif 1857 1858 int sk_setsockopt(struct sock *sk, int level, int optname, 1859 sockptr_t optval, unsigned int optlen); 1860 int sock_setsockopt(struct socket *sock, int level, int op, 1861 sockptr_t optval, unsigned int optlen); 1862 1863 int sk_getsockopt(struct sock *sk, int level, int optname, 1864 sockptr_t optval, sockptr_t optlen); 1865 int sock_getsockopt(struct socket *sock, int level, int op, 1866 char __user *optval, int __user *optlen); 1867 int sock_gettstamp(struct socket *sock, void __user *userstamp, 1868 bool timeval, bool time32); 1869 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, 1870 unsigned long data_len, int noblock, 1871 int *errcode, int max_page_order); 1872 1873 static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk, 1874 unsigned long size, 1875 int noblock, int *errcode) 1876 { 1877 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0); 1878 } 1879 1880 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority); 1881 void sock_kfree_s(struct sock *sk, void *mem, int size); 1882 void sock_kzfree_s(struct sock *sk, void *mem, int size); 1883 void sk_send_sigurg(struct sock *sk); 1884 1885 static inline void sock_replace_proto(struct sock *sk, struct proto *proto) 1886 { 1887 if (sk->sk_socket) 1888 clear_bit(SOCK_SUPPORT_ZC, &sk->sk_socket->flags); 1889 WRITE_ONCE(sk->sk_prot, proto); 1890 } 1891 1892 struct sockcm_cookie { 1893 u64 transmit_time; 1894 u32 mark; 1895 u32 tsflags; 1896 }; 1897 1898 static inline void sockcm_init(struct sockcm_cookie *sockc, 1899 const struct sock *sk) 1900 { 1901 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags }; 1902 } 1903 1904 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg, 1905 struct sockcm_cookie *sockc); 1906 int sock_cmsg_send(struct sock *sk, struct msghdr *msg, 1907 struct sockcm_cookie *sockc); 1908 1909 /* 1910 * Functions to fill in entries in struct proto_ops when a protocol 1911 * does not implement a particular function. 1912 */ 1913 int sock_no_bind(struct socket *, struct sockaddr *, int); 1914 int sock_no_connect(struct socket *, struct sockaddr *, int, int); 1915 int sock_no_socketpair(struct socket *, struct socket *); 1916 int sock_no_accept(struct socket *, struct socket *, int, bool); 1917 int sock_no_getname(struct socket *, struct sockaddr *, int); 1918 int sock_no_ioctl(struct socket *, unsigned int, unsigned long); 1919 int sock_no_listen(struct socket *, int); 1920 int sock_no_shutdown(struct socket *, int); 1921 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t); 1922 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len); 1923 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int); 1924 int sock_no_mmap(struct file *file, struct socket *sock, 1925 struct vm_area_struct *vma); 1926 1927 /* 1928 * Functions to fill in entries in struct proto_ops when a protocol 1929 * uses the inet style. 1930 */ 1931 int sock_common_getsockopt(struct socket *sock, int level, int optname, 1932 char __user *optval, int __user *optlen); 1933 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, 1934 int flags); 1935 int sock_common_setsockopt(struct socket *sock, int level, int optname, 1936 sockptr_t optval, unsigned int optlen); 1937 1938 void sk_common_release(struct sock *sk); 1939 1940 /* 1941 * Default socket callbacks and setup code 1942 */ 1943 1944 /* Initialise core socket variables using an explicit uid. */ 1945 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid); 1946 1947 /* Initialise core socket variables. 1948 * Assumes struct socket *sock is embedded in a struct socket_alloc. 1949 */ 1950 void sock_init_data(struct socket *sock, struct sock *sk); 1951 1952 /* 1953 * Socket reference counting postulates. 1954 * 1955 * * Each user of socket SHOULD hold a reference count. 1956 * * Each access point to socket (an hash table bucket, reference from a list, 1957 * running timer, skb in flight MUST hold a reference count. 1958 * * When reference count hits 0, it means it will never increase back. 1959 * * When reference count hits 0, it means that no references from 1960 * outside exist to this socket and current process on current CPU 1961 * is last user and may/should destroy this socket. 1962 * * sk_free is called from any context: process, BH, IRQ. When 1963 * it is called, socket has no references from outside -> sk_free 1964 * may release descendant resources allocated by the socket, but 1965 * to the time when it is called, socket is NOT referenced by any 1966 * hash tables, lists etc. 1967 * * Packets, delivered from outside (from network or from another process) 1968 * and enqueued on receive/error queues SHOULD NOT grab reference count, 1969 * when they sit in queue. Otherwise, packets will leak to hole, when 1970 * socket is looked up by one cpu and unhasing is made by another CPU. 1971 * It is true for udp/raw, netlink (leak to receive and error queues), tcp 1972 * (leak to backlog). Packet socket does all the processing inside 1973 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets 1974 * use separate SMP lock, so that they are prone too. 1975 */ 1976 1977 /* Ungrab socket and destroy it, if it was the last reference. */ 1978 static inline void sock_put(struct sock *sk) 1979 { 1980 if (refcount_dec_and_test(&sk->sk_refcnt)) 1981 sk_free(sk); 1982 } 1983 /* Generic version of sock_put(), dealing with all sockets 1984 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...) 1985 */ 1986 void sock_gen_put(struct sock *sk); 1987 1988 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested, 1989 unsigned int trim_cap, bool refcounted); 1990 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb, 1991 const int nested) 1992 { 1993 return __sk_receive_skb(sk, skb, nested, 1, true); 1994 } 1995 1996 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue) 1997 { 1998 /* sk_tx_queue_mapping accept only upto a 16-bit value */ 1999 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX)) 2000 return; 2001 sk->sk_tx_queue_mapping = tx_queue; 2002 } 2003 2004 #define NO_QUEUE_MAPPING USHRT_MAX 2005 2006 static inline void sk_tx_queue_clear(struct sock *sk) 2007 { 2008 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING; 2009 } 2010 2011 static inline int sk_tx_queue_get(const struct sock *sk) 2012 { 2013 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING) 2014 return sk->sk_tx_queue_mapping; 2015 2016 return -1; 2017 } 2018 2019 static inline void __sk_rx_queue_set(struct sock *sk, 2020 const struct sk_buff *skb, 2021 bool force_set) 2022 { 2023 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 2024 if (skb_rx_queue_recorded(skb)) { 2025 u16 rx_queue = skb_get_rx_queue(skb); 2026 2027 if (force_set || 2028 unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue)) 2029 WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue); 2030 } 2031 #endif 2032 } 2033 2034 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb) 2035 { 2036 __sk_rx_queue_set(sk, skb, true); 2037 } 2038 2039 static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb) 2040 { 2041 __sk_rx_queue_set(sk, skb, false); 2042 } 2043 2044 static inline void sk_rx_queue_clear(struct sock *sk) 2045 { 2046 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 2047 WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING); 2048 #endif 2049 } 2050 2051 static inline int sk_rx_queue_get(const struct sock *sk) 2052 { 2053 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING 2054 if (sk) { 2055 int res = READ_ONCE(sk->sk_rx_queue_mapping); 2056 2057 if (res != NO_QUEUE_MAPPING) 2058 return res; 2059 } 2060 #endif 2061 2062 return -1; 2063 } 2064 2065 static inline void sk_set_socket(struct sock *sk, struct socket *sock) 2066 { 2067 sk->sk_socket = sock; 2068 } 2069 2070 static inline wait_queue_head_t *sk_sleep(struct sock *sk) 2071 { 2072 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0); 2073 return &rcu_dereference_raw(sk->sk_wq)->wait; 2074 } 2075 /* Detach socket from process context. 2076 * Announce socket dead, detach it from wait queue and inode. 2077 * Note that parent inode held reference count on this struct sock, 2078 * we do not release it in this function, because protocol 2079 * probably wants some additional cleanups or even continuing 2080 * to work with this socket (TCP). 2081 */ 2082 static inline void sock_orphan(struct sock *sk) 2083 { 2084 write_lock_bh(&sk->sk_callback_lock); 2085 sock_set_flag(sk, SOCK_DEAD); 2086 sk_set_socket(sk, NULL); 2087 sk->sk_wq = NULL; 2088 write_unlock_bh(&sk->sk_callback_lock); 2089 } 2090 2091 static inline void sock_graft(struct sock *sk, struct socket *parent) 2092 { 2093 WARN_ON(parent->sk); 2094 write_lock_bh(&sk->sk_callback_lock); 2095 rcu_assign_pointer(sk->sk_wq, &parent->wq); 2096 parent->sk = sk; 2097 sk_set_socket(sk, parent); 2098 sk->sk_uid = SOCK_INODE(parent)->i_uid; 2099 security_sock_graft(sk, parent); 2100 write_unlock_bh(&sk->sk_callback_lock); 2101 } 2102 2103 kuid_t sock_i_uid(struct sock *sk); 2104 unsigned long __sock_i_ino(struct sock *sk); 2105 unsigned long sock_i_ino(struct sock *sk); 2106 2107 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk) 2108 { 2109 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0); 2110 } 2111 2112 static inline u32 net_tx_rndhash(void) 2113 { 2114 u32 v = get_random_u32(); 2115 2116 return v ?: 1; 2117 } 2118 2119 static inline void sk_set_txhash(struct sock *sk) 2120 { 2121 /* This pairs with READ_ONCE() in skb_set_hash_from_sk() */ 2122 WRITE_ONCE(sk->sk_txhash, net_tx_rndhash()); 2123 } 2124 2125 static inline bool sk_rethink_txhash(struct sock *sk) 2126 { 2127 if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) { 2128 sk_set_txhash(sk); 2129 return true; 2130 } 2131 return false; 2132 } 2133 2134 static inline struct dst_entry * 2135 __sk_dst_get(struct sock *sk) 2136 { 2137 return rcu_dereference_check(sk->sk_dst_cache, 2138 lockdep_sock_is_held(sk)); 2139 } 2140 2141 static inline struct dst_entry * 2142 sk_dst_get(struct sock *sk) 2143 { 2144 struct dst_entry *dst; 2145 2146 rcu_read_lock(); 2147 dst = rcu_dereference(sk->sk_dst_cache); 2148 if (dst && !rcuref_get(&dst->__rcuref)) 2149 dst = NULL; 2150 rcu_read_unlock(); 2151 return dst; 2152 } 2153 2154 static inline void __dst_negative_advice(struct sock *sk) 2155 { 2156 struct dst_entry *ndst, *dst = __sk_dst_get(sk); 2157 2158 if (dst && dst->ops->negative_advice) { 2159 ndst = dst->ops->negative_advice(dst); 2160 2161 if (ndst != dst) { 2162 rcu_assign_pointer(sk->sk_dst_cache, ndst); 2163 sk_tx_queue_clear(sk); 2164 sk->sk_dst_pending_confirm = 0; 2165 } 2166 } 2167 } 2168 2169 static inline void dst_negative_advice(struct sock *sk) 2170 { 2171 sk_rethink_txhash(sk); 2172 __dst_negative_advice(sk); 2173 } 2174 2175 static inline void 2176 __sk_dst_set(struct sock *sk, struct dst_entry *dst) 2177 { 2178 struct dst_entry *old_dst; 2179 2180 sk_tx_queue_clear(sk); 2181 sk->sk_dst_pending_confirm = 0; 2182 old_dst = rcu_dereference_protected(sk->sk_dst_cache, 2183 lockdep_sock_is_held(sk)); 2184 rcu_assign_pointer(sk->sk_dst_cache, dst); 2185 dst_release(old_dst); 2186 } 2187 2188 static inline void 2189 sk_dst_set(struct sock *sk, struct dst_entry *dst) 2190 { 2191 struct dst_entry *old_dst; 2192 2193 sk_tx_queue_clear(sk); 2194 sk->sk_dst_pending_confirm = 0; 2195 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst); 2196 dst_release(old_dst); 2197 } 2198 2199 static inline void 2200 __sk_dst_reset(struct sock *sk) 2201 { 2202 __sk_dst_set(sk, NULL); 2203 } 2204 2205 static inline void 2206 sk_dst_reset(struct sock *sk) 2207 { 2208 sk_dst_set(sk, NULL); 2209 } 2210 2211 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie); 2212 2213 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie); 2214 2215 static inline void sk_dst_confirm(struct sock *sk) 2216 { 2217 if (!READ_ONCE(sk->sk_dst_pending_confirm)) 2218 WRITE_ONCE(sk->sk_dst_pending_confirm, 1); 2219 } 2220 2221 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n) 2222 { 2223 if (skb_get_dst_pending_confirm(skb)) { 2224 struct sock *sk = skb->sk; 2225 2226 if (sk && READ_ONCE(sk->sk_dst_pending_confirm)) 2227 WRITE_ONCE(sk->sk_dst_pending_confirm, 0); 2228 neigh_confirm(n); 2229 } 2230 } 2231 2232 bool sk_mc_loop(struct sock *sk); 2233 2234 static inline bool sk_can_gso(const struct sock *sk) 2235 { 2236 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type); 2237 } 2238 2239 void sk_setup_caps(struct sock *sk, struct dst_entry *dst); 2240 2241 static inline void sk_gso_disable(struct sock *sk) 2242 { 2243 sk->sk_gso_disabled = 1; 2244 sk->sk_route_caps &= ~NETIF_F_GSO_MASK; 2245 } 2246 2247 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb, 2248 struct iov_iter *from, char *to, 2249 int copy, int offset) 2250 { 2251 if (skb->ip_summed == CHECKSUM_NONE) { 2252 __wsum csum = 0; 2253 if (!csum_and_copy_from_iter_full(to, copy, &csum, from)) 2254 return -EFAULT; 2255 skb->csum = csum_block_add(skb->csum, csum, offset); 2256 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) { 2257 if (!copy_from_iter_full_nocache(to, copy, from)) 2258 return -EFAULT; 2259 } else if (!copy_from_iter_full(to, copy, from)) 2260 return -EFAULT; 2261 2262 return 0; 2263 } 2264 2265 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb, 2266 struct iov_iter *from, int copy) 2267 { 2268 int err, offset = skb->len; 2269 2270 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy), 2271 copy, offset); 2272 if (err) 2273 __skb_trim(skb, offset); 2274 2275 return err; 2276 } 2277 2278 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from, 2279 struct sk_buff *skb, 2280 struct page *page, 2281 int off, int copy) 2282 { 2283 int err; 2284 2285 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off, 2286 copy, skb->len); 2287 if (err) 2288 return err; 2289 2290 skb_len_add(skb, copy); 2291 sk_wmem_queued_add(sk, copy); 2292 sk_mem_charge(sk, copy); 2293 return 0; 2294 } 2295 2296 /** 2297 * sk_wmem_alloc_get - returns write allocations 2298 * @sk: socket 2299 * 2300 * Return: sk_wmem_alloc minus initial offset of one 2301 */ 2302 static inline int sk_wmem_alloc_get(const struct sock *sk) 2303 { 2304 return refcount_read(&sk->sk_wmem_alloc) - 1; 2305 } 2306 2307 /** 2308 * sk_rmem_alloc_get - returns read allocations 2309 * @sk: socket 2310 * 2311 * Return: sk_rmem_alloc 2312 */ 2313 static inline int sk_rmem_alloc_get(const struct sock *sk) 2314 { 2315 return atomic_read(&sk->sk_rmem_alloc); 2316 } 2317 2318 /** 2319 * sk_has_allocations - check if allocations are outstanding 2320 * @sk: socket 2321 * 2322 * Return: true if socket has write or read allocations 2323 */ 2324 static inline bool sk_has_allocations(const struct sock *sk) 2325 { 2326 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk); 2327 } 2328 2329 /** 2330 * skwq_has_sleeper - check if there are any waiting processes 2331 * @wq: struct socket_wq 2332 * 2333 * Return: true if socket_wq has waiting processes 2334 * 2335 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory 2336 * barrier call. They were added due to the race found within the tcp code. 2337 * 2338 * Consider following tcp code paths:: 2339 * 2340 * CPU1 CPU2 2341 * sys_select receive packet 2342 * ... ... 2343 * __add_wait_queue update tp->rcv_nxt 2344 * ... ... 2345 * tp->rcv_nxt check sock_def_readable 2346 * ... { 2347 * schedule rcu_read_lock(); 2348 * wq = rcu_dereference(sk->sk_wq); 2349 * if (wq && waitqueue_active(&wq->wait)) 2350 * wake_up_interruptible(&wq->wait) 2351 * ... 2352 * } 2353 * 2354 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay 2355 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1 2356 * could then endup calling schedule and sleep forever if there are no more 2357 * data on the socket. 2358 * 2359 */ 2360 static inline bool skwq_has_sleeper(struct socket_wq *wq) 2361 { 2362 return wq && wq_has_sleeper(&wq->wait); 2363 } 2364 2365 /** 2366 * sock_poll_wait - place memory barrier behind the poll_wait call. 2367 * @filp: file 2368 * @sock: socket to wait on 2369 * @p: poll_table 2370 * 2371 * See the comments in the wq_has_sleeper function. 2372 */ 2373 static inline void sock_poll_wait(struct file *filp, struct socket *sock, 2374 poll_table *p) 2375 { 2376 if (!poll_does_not_wait(p)) { 2377 poll_wait(filp, &sock->wq.wait, p); 2378 /* We need to be sure we are in sync with the 2379 * socket flags modification. 2380 * 2381 * This memory barrier is paired in the wq_has_sleeper. 2382 */ 2383 smp_mb(); 2384 } 2385 } 2386 2387 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk) 2388 { 2389 /* This pairs with WRITE_ONCE() in sk_set_txhash() */ 2390 u32 txhash = READ_ONCE(sk->sk_txhash); 2391 2392 if (txhash) { 2393 skb->l4_hash = 1; 2394 skb->hash = txhash; 2395 } 2396 } 2397 2398 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk); 2399 2400 /* 2401 * Queue a received datagram if it will fit. Stream and sequenced 2402 * protocols can't normally use this as they need to fit buffers in 2403 * and play with them. 2404 * 2405 * Inlined as it's very short and called for pretty much every 2406 * packet ever received. 2407 */ 2408 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk) 2409 { 2410 skb_orphan(skb); 2411 skb->sk = sk; 2412 skb->destructor = sock_rfree; 2413 atomic_add(skb->truesize, &sk->sk_rmem_alloc); 2414 sk_mem_charge(sk, skb->truesize); 2415 } 2416 2417 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk) 2418 { 2419 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) { 2420 skb_orphan(skb); 2421 skb->destructor = sock_efree; 2422 skb->sk = sk; 2423 return true; 2424 } 2425 return false; 2426 } 2427 2428 static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk) 2429 { 2430 skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC)); 2431 if (skb) { 2432 if (sk_rmem_schedule(sk, skb, skb->truesize)) { 2433 skb_set_owner_r(skb, sk); 2434 return skb; 2435 } 2436 __kfree_skb(skb); 2437 } 2438 return NULL; 2439 } 2440 2441 static inline void skb_prepare_for_gro(struct sk_buff *skb) 2442 { 2443 if (skb->destructor != sock_wfree) { 2444 skb_orphan(skb); 2445 return; 2446 } 2447 skb->slow_gro = 1; 2448 } 2449 2450 void sk_reset_timer(struct sock *sk, struct timer_list *timer, 2451 unsigned long expires); 2452 2453 void sk_stop_timer(struct sock *sk, struct timer_list *timer); 2454 2455 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer); 2456 2457 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue, 2458 struct sk_buff *skb, unsigned int flags, 2459 void (*destructor)(struct sock *sk, 2460 struct sk_buff *skb)); 2461 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 2462 2463 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb, 2464 enum skb_drop_reason *reason); 2465 2466 static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 2467 { 2468 return sock_queue_rcv_skb_reason(sk, skb, NULL); 2469 } 2470 2471 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb); 2472 struct sk_buff *sock_dequeue_err_skb(struct sock *sk); 2473 2474 /* 2475 * Recover an error report and clear atomically 2476 */ 2477 2478 static inline int sock_error(struct sock *sk) 2479 { 2480 int err; 2481 2482 /* Avoid an atomic operation for the common case. 2483 * This is racy since another cpu/thread can change sk_err under us. 2484 */ 2485 if (likely(data_race(!sk->sk_err))) 2486 return 0; 2487 2488 err = xchg(&sk->sk_err, 0); 2489 return -err; 2490 } 2491 2492 void sk_error_report(struct sock *sk); 2493 2494 static inline unsigned long sock_wspace(struct sock *sk) 2495 { 2496 int amt = 0; 2497 2498 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) { 2499 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc); 2500 if (amt < 0) 2501 amt = 0; 2502 } 2503 return amt; 2504 } 2505 2506 /* Note: 2507 * We use sk->sk_wq_raw, from contexts knowing this 2508 * pointer is not NULL and cannot disappear/change. 2509 */ 2510 static inline void sk_set_bit(int nr, struct sock *sk) 2511 { 2512 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2513 !sock_flag(sk, SOCK_FASYNC)) 2514 return; 2515 2516 set_bit(nr, &sk->sk_wq_raw->flags); 2517 } 2518 2519 static inline void sk_clear_bit(int nr, struct sock *sk) 2520 { 2521 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) && 2522 !sock_flag(sk, SOCK_FASYNC)) 2523 return; 2524 2525 clear_bit(nr, &sk->sk_wq_raw->flags); 2526 } 2527 2528 static inline void sk_wake_async(const struct sock *sk, int how, int band) 2529 { 2530 if (sock_flag(sk, SOCK_FASYNC)) { 2531 rcu_read_lock(); 2532 sock_wake_async(rcu_dereference(sk->sk_wq), how, band); 2533 rcu_read_unlock(); 2534 } 2535 } 2536 2537 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might 2538 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak. 2539 * Note: for send buffers, TCP works better if we can build two skbs at 2540 * minimum. 2541 */ 2542 #define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff))) 2543 2544 #define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2) 2545 #define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE 2546 2547 static inline void sk_stream_moderate_sndbuf(struct sock *sk) 2548 { 2549 u32 val; 2550 2551 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK) 2552 return; 2553 2554 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1); 2555 val = max_t(u32, val, sk_unused_reserved_mem(sk)); 2556 2557 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF)); 2558 } 2559 2560 /** 2561 * sk_page_frag - return an appropriate page_frag 2562 * @sk: socket 2563 * 2564 * Use the per task page_frag instead of the per socket one for 2565 * optimization when we know that we're in process context and own 2566 * everything that's associated with %current. 2567 * 2568 * Both direct reclaim and page faults can nest inside other 2569 * socket operations and end up recursing into sk_page_frag() 2570 * while it's already in use: explicitly avoid task page_frag 2571 * when users disable sk_use_task_frag. 2572 * 2573 * Return: a per task page_frag if context allows that, 2574 * otherwise a per socket one. 2575 */ 2576 static inline struct page_frag *sk_page_frag(struct sock *sk) 2577 { 2578 if (sk->sk_use_task_frag) 2579 return ¤t->task_frag; 2580 2581 return &sk->sk_frag; 2582 } 2583 2584 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag); 2585 2586 /* 2587 * Default write policy as shown to user space via poll/select/SIGIO 2588 */ 2589 static inline bool sock_writeable(const struct sock *sk) 2590 { 2591 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1); 2592 } 2593 2594 static inline gfp_t gfp_any(void) 2595 { 2596 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2597 } 2598 2599 static inline gfp_t gfp_memcg_charge(void) 2600 { 2601 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL; 2602 } 2603 2604 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock) 2605 { 2606 return noblock ? 0 : sk->sk_rcvtimeo; 2607 } 2608 2609 static inline long sock_sndtimeo(const struct sock *sk, bool noblock) 2610 { 2611 return noblock ? 0 : sk->sk_sndtimeo; 2612 } 2613 2614 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len) 2615 { 2616 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len); 2617 2618 return v ?: 1; 2619 } 2620 2621 /* Alas, with timeout socket operations are not restartable. 2622 * Compare this to poll(). 2623 */ 2624 static inline int sock_intr_errno(long timeo) 2625 { 2626 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR; 2627 } 2628 2629 struct sock_skb_cb { 2630 u32 dropcount; 2631 }; 2632 2633 /* Store sock_skb_cb at the end of skb->cb[] so protocol families 2634 * using skb->cb[] would keep using it directly and utilize its 2635 * alignement guarantee. 2636 */ 2637 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \ 2638 sizeof(struct sock_skb_cb))) 2639 2640 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \ 2641 SOCK_SKB_CB_OFFSET)) 2642 2643 #define sock_skb_cb_check_size(size) \ 2644 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET) 2645 2646 static inline void 2647 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb) 2648 { 2649 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ? 2650 atomic_read(&sk->sk_drops) : 0; 2651 } 2652 2653 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb) 2654 { 2655 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs); 2656 2657 atomic_add(segs, &sk->sk_drops); 2658 } 2659 2660 static inline ktime_t sock_read_timestamp(struct sock *sk) 2661 { 2662 #if BITS_PER_LONG==32 2663 unsigned int seq; 2664 ktime_t kt; 2665 2666 do { 2667 seq = read_seqbegin(&sk->sk_stamp_seq); 2668 kt = sk->sk_stamp; 2669 } while (read_seqretry(&sk->sk_stamp_seq, seq)); 2670 2671 return kt; 2672 #else 2673 return READ_ONCE(sk->sk_stamp); 2674 #endif 2675 } 2676 2677 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt) 2678 { 2679 #if BITS_PER_LONG==32 2680 write_seqlock(&sk->sk_stamp_seq); 2681 sk->sk_stamp = kt; 2682 write_sequnlock(&sk->sk_stamp_seq); 2683 #else 2684 WRITE_ONCE(sk->sk_stamp, kt); 2685 #endif 2686 } 2687 2688 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk, 2689 struct sk_buff *skb); 2690 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk, 2691 struct sk_buff *skb); 2692 2693 static inline void 2694 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb) 2695 { 2696 ktime_t kt = skb->tstamp; 2697 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb); 2698 2699 /* 2700 * generate control messages if 2701 * - receive time stamping in software requested 2702 * - software time stamp available and wanted 2703 * - hardware time stamps available and wanted 2704 */ 2705 if (sock_flag(sk, SOCK_RCVTSTAMP) || 2706 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) || 2707 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) || 2708 (hwtstamps->hwtstamp && 2709 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE))) 2710 __sock_recv_timestamp(msg, sk, skb); 2711 else 2712 sock_write_timestamp(sk, kt); 2713 2714 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb_wifi_acked_valid(skb)) 2715 __sock_recv_wifi_status(msg, sk, skb); 2716 } 2717 2718 void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk, 2719 struct sk_buff *skb); 2720 2721 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC) 2722 static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk, 2723 struct sk_buff *skb) 2724 { 2725 #define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL) | \ 2726 (1UL << SOCK_RCVTSTAMP) | \ 2727 (1UL << SOCK_RCVMARK)) 2728 #define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \ 2729 SOF_TIMESTAMPING_RAW_HARDWARE) 2730 2731 if (sk->sk_flags & FLAGS_RECV_CMSGS || sk->sk_tsflags & TSFLAGS_ANY) 2732 __sock_recv_cmsgs(msg, sk, skb); 2733 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP))) 2734 sock_write_timestamp(sk, skb->tstamp); 2735 else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP)) 2736 sock_write_timestamp(sk, 0); 2737 } 2738 2739 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags); 2740 2741 /** 2742 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped 2743 * @sk: socket sending this packet 2744 * @tsflags: timestamping flags to use 2745 * @tx_flags: completed with instructions for time stamping 2746 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno) 2747 * 2748 * Note: callers should take care of initial ``*tx_flags`` value (usually 0) 2749 */ 2750 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2751 __u8 *tx_flags, __u32 *tskey) 2752 { 2753 if (unlikely(tsflags)) { 2754 __sock_tx_timestamp(tsflags, tx_flags); 2755 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey && 2756 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK) 2757 *tskey = atomic_inc_return(&sk->sk_tskey) - 1; 2758 } 2759 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS))) 2760 *tx_flags |= SKBTX_WIFI_STATUS; 2761 } 2762 2763 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags, 2764 __u8 *tx_flags) 2765 { 2766 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL); 2767 } 2768 2769 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags) 2770 { 2771 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags, 2772 &skb_shinfo(skb)->tskey); 2773 } 2774 2775 static inline bool sk_is_tcp(const struct sock *sk) 2776 { 2777 return sk->sk_type == SOCK_STREAM && sk->sk_protocol == IPPROTO_TCP; 2778 } 2779 2780 /** 2781 * sk_eat_skb - Release a skb if it is no longer needed 2782 * @sk: socket to eat this skb from 2783 * @skb: socket buffer to eat 2784 * 2785 * This routine must be called with interrupts disabled or with the socket 2786 * locked so that the sk_buff queue operation is ok. 2787 */ 2788 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb) 2789 { 2790 __skb_unlink(skb, &sk->sk_receive_queue); 2791 __kfree_skb(skb); 2792 } 2793 2794 static inline bool 2795 skb_sk_is_prefetched(struct sk_buff *skb) 2796 { 2797 #ifdef CONFIG_INET 2798 return skb->destructor == sock_pfree; 2799 #else 2800 return false; 2801 #endif /* CONFIG_INET */ 2802 } 2803 2804 /* This helper checks if a socket is a full socket, 2805 * ie _not_ a timewait or request socket. 2806 */ 2807 static inline bool sk_fullsock(const struct sock *sk) 2808 { 2809 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV); 2810 } 2811 2812 static inline bool 2813 sk_is_refcounted(struct sock *sk) 2814 { 2815 /* Only full sockets have sk->sk_flags. */ 2816 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE); 2817 } 2818 2819 /** 2820 * skb_steal_sock - steal a socket from an sk_buff 2821 * @skb: sk_buff to steal the socket from 2822 * @refcounted: is set to true if the socket is reference-counted 2823 */ 2824 static inline struct sock * 2825 skb_steal_sock(struct sk_buff *skb, bool *refcounted) 2826 { 2827 if (skb->sk) { 2828 struct sock *sk = skb->sk; 2829 2830 *refcounted = true; 2831 if (skb_sk_is_prefetched(skb)) 2832 *refcounted = sk_is_refcounted(sk); 2833 skb->destructor = NULL; 2834 skb->sk = NULL; 2835 return sk; 2836 } 2837 *refcounted = false; 2838 return NULL; 2839 } 2840 2841 /* Checks if this SKB belongs to an HW offloaded socket 2842 * and whether any SW fallbacks are required based on dev. 2843 * Check decrypted mark in case skb_orphan() cleared socket. 2844 */ 2845 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb, 2846 struct net_device *dev) 2847 { 2848 #ifdef CONFIG_SOCK_VALIDATE_XMIT 2849 struct sock *sk = skb->sk; 2850 2851 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) { 2852 skb = sk->sk_validate_xmit_skb(sk, dev, skb); 2853 #ifdef CONFIG_TLS_DEVICE 2854 } else if (unlikely(skb->decrypted)) { 2855 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n"); 2856 kfree_skb(skb); 2857 skb = NULL; 2858 #endif 2859 } 2860 #endif 2861 2862 return skb; 2863 } 2864 2865 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV 2866 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE) 2867 */ 2868 static inline bool sk_listener(const struct sock *sk) 2869 { 2870 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV); 2871 } 2872 2873 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag); 2874 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level, 2875 int type); 2876 2877 bool sk_ns_capable(const struct sock *sk, 2878 struct user_namespace *user_ns, int cap); 2879 bool sk_capable(const struct sock *sk, int cap); 2880 bool sk_net_capable(const struct sock *sk, int cap); 2881 2882 void sk_get_meminfo(const struct sock *sk, u32 *meminfo); 2883 2884 /* Take into consideration the size of the struct sk_buff overhead in the 2885 * determination of these values, since that is non-constant across 2886 * platforms. This makes socket queueing behavior and performance 2887 * not depend upon such differences. 2888 */ 2889 #define _SK_MEM_PACKETS 256 2890 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256) 2891 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2892 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) 2893 2894 extern __u32 sysctl_wmem_max; 2895 extern __u32 sysctl_rmem_max; 2896 2897 extern int sysctl_tstamp_allow_data; 2898 extern int sysctl_optmem_max; 2899 2900 extern __u32 sysctl_wmem_default; 2901 extern __u32 sysctl_rmem_default; 2902 2903 #define SKB_FRAG_PAGE_ORDER get_order(32768) 2904 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key); 2905 2906 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto) 2907 { 2908 /* Does this proto have per netns sysctl_wmem ? */ 2909 if (proto->sysctl_wmem_offset) 2910 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset)); 2911 2912 return READ_ONCE(*proto->sysctl_wmem); 2913 } 2914 2915 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) 2916 { 2917 /* Does this proto have per netns sysctl_rmem ? */ 2918 if (proto->sysctl_rmem_offset) 2919 return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset)); 2920 2921 return READ_ONCE(*proto->sysctl_rmem); 2922 } 2923 2924 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10) 2925 * Some wifi drivers need to tweak it to get more chunks. 2926 * They can use this helper from their ndo_start_xmit() 2927 */ 2928 static inline void sk_pacing_shift_update(struct sock *sk, int val) 2929 { 2930 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val) 2931 return; 2932 WRITE_ONCE(sk->sk_pacing_shift, val); 2933 } 2934 2935 /* if a socket is bound to a device, check that the given device 2936 * index is either the same or that the socket is bound to an L3 2937 * master device and the given device index is also enslaved to 2938 * that L3 master 2939 */ 2940 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif) 2941 { 2942 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if); 2943 int mdif; 2944 2945 if (!bound_dev_if || bound_dev_if == dif) 2946 return true; 2947 2948 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif); 2949 if (mdif && mdif == bound_dev_if) 2950 return true; 2951 2952 return false; 2953 } 2954 2955 void sock_def_readable(struct sock *sk); 2956 2957 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk); 2958 void sock_set_timestamp(struct sock *sk, int optname, bool valbool); 2959 int sock_set_timestamping(struct sock *sk, int optname, 2960 struct so_timestamping timestamping); 2961 2962 void sock_enable_timestamps(struct sock *sk); 2963 void sock_no_linger(struct sock *sk); 2964 void sock_set_keepalive(struct sock *sk); 2965 void sock_set_priority(struct sock *sk, u32 priority); 2966 void sock_set_rcvbuf(struct sock *sk, int val); 2967 void sock_set_mark(struct sock *sk, u32 val); 2968 void sock_set_reuseaddr(struct sock *sk); 2969 void sock_set_reuseport(struct sock *sk); 2970 void sock_set_sndtimeo(struct sock *sk, s64 secs); 2971 2972 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len); 2973 2974 int sock_get_timeout(long timeo, void *optval, bool old_timeval); 2975 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv, 2976 sockptr_t optval, int optlen, bool old_timeval); 2977 2978 int sock_ioctl_inout(struct sock *sk, unsigned int cmd, 2979 void __user *arg, void *karg, size_t size); 2980 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg); 2981 static inline bool sk_is_readable(struct sock *sk) 2982 { 2983 if (sk->sk_prot->sock_is_readable) 2984 return sk->sk_prot->sock_is_readable(sk); 2985 return false; 2986 } 2987 #endif /* _SOCK_H */ 2988