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1/*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Definitions for the AF_INET socket handler.
7 *
8 * Version: @(#)sock.h 1.0.4 05/13/93
9 *
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Corey Minyard <wf-rch!minyard@relay.EU.net>
13 * Florian La Roche <flla@stud.uni-sb.de>
14 *
15 * Fixes:
16 * Alan Cox : Volatiles in skbuff pointers. See
17 * skbuff comments. May be overdone,
18 * better to prove they can be removed
19 * than the reverse.
20 * Alan Cox : Added a zapped field for tcp to note
21 * a socket is reset and must stay shut up
22 * Alan Cox : New fields for options
23 * Pauline Middelink : identd support
24 * Alan Cox : Eliminate low level recv/recvfrom
25 * David S. Miller : New socket lookup architecture.
26 * Steve Whitehouse: Default routines for sock_ops
27 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made
28 * protinfo be just a void pointer, as the
29 * protocol specific parts were moved to
30 * respective headers and ipv4/v6, etc now
31 * use private slabcaches for its socks
32 * Pedro Hortas : New flags field for socket options
33 *
34 *
35 * This program is free software; you can redistribute it and/or
36 * modify it under the terms of the GNU General Public License
37 * as published by the Free Software Foundation; either version
38 * 2 of the License, or (at your option) any later version.
39 */
40#ifndef _SOCK_H
41#define _SOCK_H
42
43#include <linux/hardirq.h>
44#include <linux/kernel.h>
45#include <linux/list.h>
46#include <linux/list_nulls.h>
47#include <linux/timer.h>
48#include <linux/cache.h>
49#include <linux/bitops.h>
50#include <linux/lockdep.h>
51#include <linux/netdevice.h>
52#include <linux/skbuff.h> /* struct sk_buff */
53#include <linux/mm.h>
54#include <linux/security.h>
55#include <linux/slab.h>
56#include <linux/uaccess.h>
57#include <linux/page_counter.h>
58#include <linux/memcontrol.h>
59#include <linux/static_key.h>
60#include <linux/sched.h>
61#include <linux/wait.h>
62#include <linux/cgroup-defs.h>
63#include <linux/rbtree.h>
64#include <linux/filter.h>
65#include <linux/rculist_nulls.h>
66#include <linux/poll.h>
67
68#include <linux/atomic.h>
69#include <linux/refcount.h>
70#include <net/dst.h>
71#include <net/checksum.h>
72#include <net/tcp_states.h>
73#include <linux/net_tstamp.h>
74#include <net/smc.h>
75#include <net/l3mdev.h>
76
77/*
78 * This structure really needs to be cleaned up.
79 * Most of it is for TCP, and not used by any of
80 * the other protocols.
81 */
82
83/* Define this to get the SOCK_DBG debugging facility. */
84#define SOCK_DEBUGGING
85#ifdef SOCK_DEBUGGING
86#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
87 printk(KERN_DEBUG msg); } while (0)
88#else
89/* Validate arguments and do nothing */
90static inline __printf(2, 3)
91void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
92{
93}
94#endif
95
96/* This is the per-socket lock. The spinlock provides a synchronization
97 * between user contexts and software interrupt processing, whereas the
98 * mini-semaphore synchronizes multiple users amongst themselves.
99 */
100typedef struct {
101 spinlock_t slock;
102 int owned;
103 wait_queue_head_t wq;
104 /*
105 * We express the mutex-alike socket_lock semantics
106 * to the lock validator by explicitly managing
107 * the slock as a lock variant (in addition to
108 * the slock itself):
109 */
110#ifdef CONFIG_DEBUG_LOCK_ALLOC
111 struct lockdep_map dep_map;
112#endif
113} socket_lock_t;
114
115struct sock;
116struct proto;
117struct net;
118
119typedef __u32 __bitwise __portpair;
120typedef __u64 __bitwise __addrpair;
121
122/**
123 * struct sock_common - minimal network layer representation of sockets
124 * @skc_daddr: Foreign IPv4 addr
125 * @skc_rcv_saddr: Bound local IPv4 addr
126 * @skc_hash: hash value used with various protocol lookup tables
127 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
128 * @skc_dport: placeholder for inet_dport/tw_dport
129 * @skc_num: placeholder for inet_num/tw_num
130 * @skc_family: network address family
131 * @skc_state: Connection state
132 * @skc_reuse: %SO_REUSEADDR setting
133 * @skc_reuseport: %SO_REUSEPORT setting
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_node: main hash linkage for various protocol lookup tables
140 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
141 * @skc_tx_queue_mapping: tx queue number for this connection
142 * @skc_flags: place holder for sk_flags
143 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
144 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
145 * @skc_incoming_cpu: record/match cpu processing incoming packets
146 * @skc_refcnt: reference count
147 *
148 * This is the minimal network layer representation of sockets, the header
149 * for struct sock and struct inet_timewait_sock.
150 */
151struct sock_common {
152 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
153 * address on 64bit arches : cf INET_MATCH()
154 */
155 union {
156 __addrpair skc_addrpair;
157 struct {
158 __be32 skc_daddr;
159 __be32 skc_rcv_saddr;
160 };
161 };
162 union {
163 unsigned int skc_hash;
164 __u16 skc_u16hashes[2];
165 };
166 /* skc_dport && skc_num must be grouped as well */
167 union {
168 __portpair skc_portpair;
169 struct {
170 __be16 skc_dport;
171 __u16 skc_num;
172 };
173 };
174
175 unsigned short skc_family;
176 volatile unsigned char skc_state;
177 unsigned char skc_reuse:4;
178 unsigned char skc_reuseport:1;
179 unsigned char skc_ipv6only:1;
180 unsigned char skc_net_refcnt:1;
181 int skc_bound_dev_if;
182 union {
183 struct hlist_node skc_bind_node;
184 struct hlist_node skc_portaddr_node;
185 };
186 struct proto *skc_prot;
187 possible_net_t skc_net;
188
189#if IS_ENABLED(CONFIG_IPV6)
190 struct in6_addr skc_v6_daddr;
191 struct in6_addr skc_v6_rcv_saddr;
192#endif
193
194 atomic64_t skc_cookie;
195
196 /* following fields are padding to force
197 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
198 * assuming IPV6 is enabled. We use this padding differently
199 * for different kind of 'sockets'
200 */
201 union {
202 unsigned long skc_flags;
203 struct sock *skc_listener; /* request_sock */
204 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
205 };
206 /*
207 * fields between dontcopy_begin/dontcopy_end
208 * are not copied in sock_copy()
209 */
210 /* private: */
211 int skc_dontcopy_begin[0];
212 /* public: */
213 union {
214 struct hlist_node skc_node;
215 struct hlist_nulls_node skc_nulls_node;
216 };
217 int skc_tx_queue_mapping;
218 union {
219 int skc_incoming_cpu;
220 u32 skc_rcv_wnd;
221 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */
222 };
223
224 refcount_t skc_refcnt;
225 /* private: */
226 int skc_dontcopy_end[0];
227 union {
228 u32 skc_rxhash;
229 u32 skc_window_clamp;
230 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */
231 };
232 /* public: */
233};
234
235/**
236 * struct sock - network layer representation of sockets
237 * @__sk_common: shared layout with inet_timewait_sock
238 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
239 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
240 * @sk_lock: synchronizer
241 * @sk_kern_sock: True if sock is using kernel lock classes
242 * @sk_rcvbuf: size of receive buffer in bytes
243 * @sk_wq: sock wait queue and async head
244 * @sk_rx_dst: receive input route used by early demux
245 * @sk_dst_cache: destination cache
246 * @sk_dst_pending_confirm: need to confirm neighbour
247 * @sk_policy: flow policy
248 * @sk_receive_queue: incoming packets
249 * @sk_wmem_alloc: transmit queue bytes committed
250 * @sk_tsq_flags: TCP Small Queues flags
251 * @sk_write_queue: Packet sending queue
252 * @sk_omem_alloc: "o" is "option" or "other"
253 * @sk_wmem_queued: persistent queue size
254 * @sk_forward_alloc: space allocated forward
255 * @sk_napi_id: id of the last napi context to receive data for sk
256 * @sk_ll_usec: usecs to busypoll when there is no data
257 * @sk_allocation: allocation mode
258 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
259 * @sk_pacing_status: Pacing status (requested, handled by sch_fq)
260 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
261 * @sk_sndbuf: size of send buffer in bytes
262 * @__sk_flags_offset: empty field used to determine location of bitfield
263 * @sk_padding: unused element for alignment
264 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
265 * @sk_no_check_rx: allow zero checksum in RX packets
266 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
267 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
268 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
269 * @sk_gso_max_size: Maximum GSO segment size to build
270 * @sk_gso_max_segs: Maximum number of GSO segments
271 * @sk_pacing_shift: scaling factor for TCP Small Queues
272 * @sk_lingertime: %SO_LINGER l_linger setting
273 * @sk_backlog: always used with the per-socket spinlock held
274 * @sk_callback_lock: used with the callbacks in the end of this struct
275 * @sk_error_queue: rarely used
276 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
277 * IPV6_ADDRFORM for instance)
278 * @sk_err: last error
279 * @sk_err_soft: errors that don't cause failure but are the cause of a
280 * persistent failure not just 'timed out'
281 * @sk_drops: raw/udp drops counter
282 * @sk_ack_backlog: current listen backlog
283 * @sk_max_ack_backlog: listen backlog set in listen()
284 * @sk_uid: user id of owner
285 * @sk_priority: %SO_PRIORITY setting
286 * @sk_type: socket type (%SOCK_STREAM, etc)
287 * @sk_protocol: which protocol this socket belongs in this network family
288 * @sk_peer_pid: &struct pid for this socket's peer
289 * @sk_peer_cred: %SO_PEERCRED setting
290 * @sk_rcvlowat: %SO_RCVLOWAT setting
291 * @sk_rcvtimeo: %SO_RCVTIMEO setting
292 * @sk_sndtimeo: %SO_SNDTIMEO setting
293 * @sk_txhash: computed flow hash for use on transmit
294 * @sk_filter: socket filtering instructions
295 * @sk_timer: sock cleanup timer
296 * @sk_stamp: time stamp of last packet received
297 * @sk_tsflags: SO_TIMESTAMPING socket options
298 * @sk_tskey: counter to disambiguate concurrent tstamp requests
299 * @sk_zckey: counter to order MSG_ZEROCOPY notifications
300 * @sk_socket: Identd and reporting IO signals
301 * @sk_user_data: RPC layer private data
302 * @sk_frag: cached page frag
303 * @sk_peek_off: current peek_offset value
304 * @sk_send_head: front of stuff to transmit
305 * @sk_security: used by security modules
306 * @sk_mark: generic packet mark
307 * @sk_cgrp_data: cgroup data for this cgroup
308 * @sk_memcg: this socket's memory cgroup association
309 * @sk_write_pending: a write to stream socket waits to start
310 * @sk_state_change: callback to indicate change in the state of the sock
311 * @sk_data_ready: callback to indicate there is data to be processed
312 * @sk_write_space: callback to indicate there is bf sending space available
313 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
314 * @sk_backlog_rcv: callback to process the backlog
315 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
316 * @sk_reuseport_cb: reuseport group container
317 * @sk_rcu: used during RCU grace period
318 */
319struct sock {
320 /*
321 * Now struct inet_timewait_sock also uses sock_common, so please just
322 * don't add nothing before this first member (__sk_common) --acme
323 */
324 struct sock_common __sk_common;
325#define sk_node __sk_common.skc_node
326#define sk_nulls_node __sk_common.skc_nulls_node
327#define sk_refcnt __sk_common.skc_refcnt
328#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
329
330#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
331#define sk_dontcopy_end __sk_common.skc_dontcopy_end
332#define sk_hash __sk_common.skc_hash
333#define sk_portpair __sk_common.skc_portpair
334#define sk_num __sk_common.skc_num
335#define sk_dport __sk_common.skc_dport
336#define sk_addrpair __sk_common.skc_addrpair
337#define sk_daddr __sk_common.skc_daddr
338#define sk_rcv_saddr __sk_common.skc_rcv_saddr
339#define sk_family __sk_common.skc_family
340#define sk_state __sk_common.skc_state
341#define sk_reuse __sk_common.skc_reuse
342#define sk_reuseport __sk_common.skc_reuseport
343#define sk_ipv6only __sk_common.skc_ipv6only
344#define sk_net_refcnt __sk_common.skc_net_refcnt
345#define sk_bound_dev_if __sk_common.skc_bound_dev_if
346#define sk_bind_node __sk_common.skc_bind_node
347#define sk_prot __sk_common.skc_prot
348#define sk_net __sk_common.skc_net
349#define sk_v6_daddr __sk_common.skc_v6_daddr
350#define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
351#define sk_cookie __sk_common.skc_cookie
352#define sk_incoming_cpu __sk_common.skc_incoming_cpu
353#define sk_flags __sk_common.skc_flags
354#define sk_rxhash __sk_common.skc_rxhash
355
356 socket_lock_t sk_lock;
357 atomic_t sk_drops;
358 int sk_rcvlowat;
359 struct sk_buff_head sk_error_queue;
360 struct sk_buff_head sk_receive_queue;
361 /*
362 * The backlog queue is special, it is always used with
363 * the per-socket spinlock held and requires low latency
364 * access. Therefore we special case it's implementation.
365 * Note : rmem_alloc is in this structure to fill a hole
366 * on 64bit arches, not because its logically part of
367 * backlog.
368 */
369 struct {
370 atomic_t rmem_alloc;
371 int len;
372 struct sk_buff *head;
373 struct sk_buff *tail;
374 } sk_backlog;
375#define sk_rmem_alloc sk_backlog.rmem_alloc
376
377 int sk_forward_alloc;
378#ifdef CONFIG_NET_RX_BUSY_POLL
379 unsigned int sk_ll_usec;
380 /* ===== mostly read cache line ===== */
381 unsigned int sk_napi_id;
382#endif
383 int sk_rcvbuf;
384
385 struct sk_filter __rcu *sk_filter;
386 union {
387 struct socket_wq __rcu *sk_wq;
388 struct socket_wq *sk_wq_raw;
389 };
390#ifdef CONFIG_XFRM
391 struct xfrm_policy __rcu *sk_policy[2];
392#endif
393 struct dst_entry *sk_rx_dst;
394 struct dst_entry __rcu *sk_dst_cache;
395 atomic_t sk_omem_alloc;
396 int sk_sndbuf;
397
398 /* ===== cache line for TX ===== */
399 int sk_wmem_queued;
400 refcount_t sk_wmem_alloc;
401 unsigned long sk_tsq_flags;
402 union {
403 struct sk_buff *sk_send_head;
404 struct rb_root tcp_rtx_queue;
405 };
406 struct sk_buff_head sk_write_queue;
407 __s32 sk_peek_off;
408 int sk_write_pending;
409 __u32 sk_dst_pending_confirm;
410 u32 sk_pacing_status; /* see enum sk_pacing */
411 long sk_sndtimeo;
412 struct timer_list sk_timer;
413 __u32 sk_priority;
414 __u32 sk_mark;
415 u32 sk_pacing_rate; /* bytes per second */
416 u32 sk_max_pacing_rate;
417 struct page_frag sk_frag;
418 netdev_features_t sk_route_caps;
419 netdev_features_t sk_route_nocaps;
420 netdev_features_t sk_route_forced_caps;
421 int sk_gso_type;
422 unsigned int sk_gso_max_size;
423 gfp_t sk_allocation;
424 __u32 sk_txhash;
425
426 /*
427 * Because of non atomicity rules, all
428 * changes are protected by socket lock.
429 */
430 unsigned int __sk_flags_offset[0];
431#ifdef __BIG_ENDIAN_BITFIELD
432#define SK_FL_PROTO_SHIFT 16
433#define SK_FL_PROTO_MASK 0x00ff0000
434
435#define SK_FL_TYPE_SHIFT 0
436#define SK_FL_TYPE_MASK 0x0000ffff
437#else
438#define SK_FL_PROTO_SHIFT 8
439#define SK_FL_PROTO_MASK 0x0000ff00
440
441#define SK_FL_TYPE_SHIFT 16
442#define SK_FL_TYPE_MASK 0xffff0000
443#endif
444
445 unsigned int sk_padding : 1,
446 sk_kern_sock : 1,
447 sk_no_check_tx : 1,
448 sk_no_check_rx : 1,
449 sk_userlocks : 4,
450 sk_protocol : 8,
451 sk_type : 16;
452#define SK_PROTOCOL_MAX U8_MAX
453 u16 sk_gso_max_segs;
454 u8 sk_pacing_shift;
455 unsigned long sk_lingertime;
456 struct proto *sk_prot_creator;
457 rwlock_t sk_callback_lock;
458 int sk_err,
459 sk_err_soft;
460 u32 sk_ack_backlog;
461 u32 sk_max_ack_backlog;
462 kuid_t sk_uid;
463 struct pid *sk_peer_pid;
464 const struct cred *sk_peer_cred;
465 long sk_rcvtimeo;
466 ktime_t sk_stamp;
467 u16 sk_tsflags;
468 u8 sk_shutdown;
469 u32 sk_tskey;
470 atomic_t sk_zckey;
471 struct socket *sk_socket;
472 void *sk_user_data;
473#ifdef CONFIG_SECURITY
474 void *sk_security;
475#endif
476 struct sock_cgroup_data sk_cgrp_data;
477 struct mem_cgroup *sk_memcg;
478 void (*sk_state_change)(struct sock *sk);
479 void (*sk_data_ready)(struct sock *sk);
480 void (*sk_write_space)(struct sock *sk);
481 void (*sk_error_report)(struct sock *sk);
482 int (*sk_backlog_rcv)(struct sock *sk,
483 struct sk_buff *skb);
484 void (*sk_destruct)(struct sock *sk);
485 struct sock_reuseport __rcu *sk_reuseport_cb;
486 struct rcu_head sk_rcu;
487};
488
489enum sk_pacing {
490 SK_PACING_NONE = 0,
491 SK_PACING_NEEDED = 1,
492 SK_PACING_FQ = 2,
493};
494
495#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
496
497#define rcu_dereference_sk_user_data(sk) rcu_dereference(__sk_user_data((sk)))
498#define rcu_assign_sk_user_data(sk, ptr) rcu_assign_pointer(__sk_user_data((sk)), ptr)
499
500/*
501 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
502 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
503 * on a socket means that the socket will reuse everybody else's port
504 * without looking at the other's sk_reuse value.
505 */
506
507#define SK_NO_REUSE 0
508#define SK_CAN_REUSE 1
509#define SK_FORCE_REUSE 2
510
511int sk_set_peek_off(struct sock *sk, int val);
512
513static inline int sk_peek_offset(struct sock *sk, int flags)
514{
515 if (unlikely(flags & MSG_PEEK)) {
516 return READ_ONCE(sk->sk_peek_off);
517 }
518
519 return 0;
520}
521
522static inline void sk_peek_offset_bwd(struct sock *sk, int val)
523{
524 s32 off = READ_ONCE(sk->sk_peek_off);
525
526 if (unlikely(off >= 0)) {
527 off = max_t(s32, off - val, 0);
528 WRITE_ONCE(sk->sk_peek_off, off);
529 }
530}
531
532static inline void sk_peek_offset_fwd(struct sock *sk, int val)
533{
534 sk_peek_offset_bwd(sk, -val);
535}
536
537/*
538 * Hashed lists helper routines
539 */
540static inline struct sock *sk_entry(const struct hlist_node *node)
541{
542 return hlist_entry(node, struct sock, sk_node);
543}
544
545static inline struct sock *__sk_head(const struct hlist_head *head)
546{
547 return hlist_entry(head->first, struct sock, sk_node);
548}
549
550static inline struct sock *sk_head(const struct hlist_head *head)
551{
552 return hlist_empty(head) ? NULL : __sk_head(head);
553}
554
555static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
556{
557 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
558}
559
560static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
561{
562 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
563}
564
565static inline struct sock *sk_next(const struct sock *sk)
566{
567 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
568}
569
570static inline struct sock *sk_nulls_next(const struct sock *sk)
571{
572 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
573 hlist_nulls_entry(sk->sk_nulls_node.next,
574 struct sock, sk_nulls_node) :
575 NULL;
576}
577
578static inline bool sk_unhashed(const struct sock *sk)
579{
580 return hlist_unhashed(&sk->sk_node);
581}
582
583static inline bool sk_hashed(const struct sock *sk)
584{
585 return !sk_unhashed(sk);
586}
587
588static inline void sk_node_init(struct hlist_node *node)
589{
590 node->pprev = NULL;
591}
592
593static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
594{
595 node->pprev = NULL;
596}
597
598static inline void __sk_del_node(struct sock *sk)
599{
600 __hlist_del(&sk->sk_node);
601}
602
603/* NB: equivalent to hlist_del_init_rcu */
604static inline bool __sk_del_node_init(struct sock *sk)
605{
606 if (sk_hashed(sk)) {
607 __sk_del_node(sk);
608 sk_node_init(&sk->sk_node);
609 return true;
610 }
611 return false;
612}
613
614/* Grab socket reference count. This operation is valid only
615 when sk is ALREADY grabbed f.e. it is found in hash table
616 or a list and the lookup is made under lock preventing hash table
617 modifications.
618 */
619
620static __always_inline void sock_hold(struct sock *sk)
621{
622 refcount_inc(&sk->sk_refcnt);
623}
624
625/* Ungrab socket in the context, which assumes that socket refcnt
626 cannot hit zero, f.e. it is true in context of any socketcall.
627 */
628static __always_inline void __sock_put(struct sock *sk)
629{
630 refcount_dec(&sk->sk_refcnt);
631}
632
633static inline bool sk_del_node_init(struct sock *sk)
634{
635 bool rc = __sk_del_node_init(sk);
636
637 if (rc) {
638 /* paranoid for a while -acme */
639 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
640 __sock_put(sk);
641 }
642 return rc;
643}
644#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
645
646static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
647{
648 if (sk_hashed(sk)) {
649 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
650 return true;
651 }
652 return false;
653}
654
655static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
656{
657 bool rc = __sk_nulls_del_node_init_rcu(sk);
658
659 if (rc) {
660 /* paranoid for a while -acme */
661 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
662 __sock_put(sk);
663 }
664 return rc;
665}
666
667static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
668{
669 hlist_add_head(&sk->sk_node, list);
670}
671
672static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
673{
674 sock_hold(sk);
675 __sk_add_node(sk, list);
676}
677
678static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
679{
680 sock_hold(sk);
681 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
682 sk->sk_family == AF_INET6)
683 hlist_add_tail_rcu(&sk->sk_node, list);
684 else
685 hlist_add_head_rcu(&sk->sk_node, list);
686}
687
688static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
689{
690 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
691}
692
693static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
694{
695 sock_hold(sk);
696 __sk_nulls_add_node_rcu(sk, list);
697}
698
699static inline void __sk_del_bind_node(struct sock *sk)
700{
701 __hlist_del(&sk->sk_bind_node);
702}
703
704static inline void sk_add_bind_node(struct sock *sk,
705 struct hlist_head *list)
706{
707 hlist_add_head(&sk->sk_bind_node, list);
708}
709
710#define sk_for_each(__sk, list) \
711 hlist_for_each_entry(__sk, list, sk_node)
712#define sk_for_each_rcu(__sk, list) \
713 hlist_for_each_entry_rcu(__sk, list, sk_node)
714#define sk_nulls_for_each(__sk, node, list) \
715 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
716#define sk_nulls_for_each_rcu(__sk, node, list) \
717 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
718#define sk_for_each_from(__sk) \
719 hlist_for_each_entry_from(__sk, sk_node)
720#define sk_nulls_for_each_from(__sk, node) \
721 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
722 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
723#define sk_for_each_safe(__sk, tmp, list) \
724 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
725#define sk_for_each_bound(__sk, list) \
726 hlist_for_each_entry(__sk, list, sk_bind_node)
727
728/**
729 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
730 * @tpos: the type * to use as a loop cursor.
731 * @pos: the &struct hlist_node to use as a loop cursor.
732 * @head: the head for your list.
733 * @offset: offset of hlist_node within the struct.
734 *
735 */
736#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \
737 for (pos = rcu_dereference(hlist_first_rcu(head)); \
738 pos != NULL && \
739 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
740 pos = rcu_dereference(hlist_next_rcu(pos)))
741
742static inline struct user_namespace *sk_user_ns(struct sock *sk)
743{
744 /* Careful only use this in a context where these parameters
745 * can not change and must all be valid, such as recvmsg from
746 * userspace.
747 */
748 return sk->sk_socket->file->f_cred->user_ns;
749}
750
751/* Sock flags */
752enum sock_flags {
753 SOCK_DEAD,
754 SOCK_DONE,
755 SOCK_URGINLINE,
756 SOCK_KEEPOPEN,
757 SOCK_LINGER,
758 SOCK_DESTROY,
759 SOCK_BROADCAST,
760 SOCK_TIMESTAMP,
761 SOCK_ZAPPED,
762 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
763 SOCK_DBG, /* %SO_DEBUG setting */
764 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
765 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
766 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
767 SOCK_QUEUE_SHRUNK, /* write queue has been shrunk recently */
768 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
769 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
770 SOCK_FASYNC, /* fasync() active */
771 SOCK_RXQ_OVFL,
772 SOCK_ZEROCOPY, /* buffers from userspace */
773 SOCK_WIFI_STATUS, /* push wifi status to userspace */
774 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
775 * Will use last 4 bytes of packet sent from
776 * user-space instead.
777 */
778 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
779 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
780 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
781};
782
783#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
784
785static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
786{
787 nsk->sk_flags = osk->sk_flags;
788}
789
790static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
791{
792 __set_bit(flag, &sk->sk_flags);
793}
794
795static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
796{
797 __clear_bit(flag, &sk->sk_flags);
798}
799
800static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
801{
802 return test_bit(flag, &sk->sk_flags);
803}
804
805#ifdef CONFIG_NET
806extern struct static_key memalloc_socks;
807static inline int sk_memalloc_socks(void)
808{
809 return static_key_false(&memalloc_socks);
810}
811#else
812
813static inline int sk_memalloc_socks(void)
814{
815 return 0;
816}
817
818#endif
819
820static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
821{
822 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
823}
824
825static inline void sk_acceptq_removed(struct sock *sk)
826{
827 sk->sk_ack_backlog--;
828}
829
830static inline void sk_acceptq_added(struct sock *sk)
831{
832 sk->sk_ack_backlog++;
833}
834
835static inline bool sk_acceptq_is_full(const struct sock *sk)
836{
837 return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
838}
839
840/*
841 * Compute minimal free write space needed to queue new packets.
842 */
843static inline int sk_stream_min_wspace(const struct sock *sk)
844{
845 return sk->sk_wmem_queued >> 1;
846}
847
848static inline int sk_stream_wspace(const struct sock *sk)
849{
850 return sk->sk_sndbuf - sk->sk_wmem_queued;
851}
852
853void sk_stream_write_space(struct sock *sk);
854
855/* OOB backlog add */
856static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
857{
858 /* dont let skb dst not refcounted, we are going to leave rcu lock */
859 skb_dst_force(skb);
860
861 if (!sk->sk_backlog.tail)
862 sk->sk_backlog.head = skb;
863 else
864 sk->sk_backlog.tail->next = skb;
865
866 sk->sk_backlog.tail = skb;
867 skb->next = NULL;
868}
869
870/*
871 * Take into account size of receive queue and backlog queue
872 * Do not take into account this skb truesize,
873 * to allow even a single big packet to come.
874 */
875static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
876{
877 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
878
879 return qsize > limit;
880}
881
882/* The per-socket spinlock must be held here. */
883static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
884 unsigned int limit)
885{
886 if (sk_rcvqueues_full(sk, limit))
887 return -ENOBUFS;
888
889 /*
890 * If the skb was allocated from pfmemalloc reserves, only
891 * allow SOCK_MEMALLOC sockets to use it as this socket is
892 * helping free memory
893 */
894 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
895 return -ENOMEM;
896
897 __sk_add_backlog(sk, skb);
898 sk->sk_backlog.len += skb->truesize;
899 return 0;
900}
901
902int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
903
904static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
905{
906 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
907 return __sk_backlog_rcv(sk, skb);
908
909 return sk->sk_backlog_rcv(sk, skb);
910}
911
912static inline void sk_incoming_cpu_update(struct sock *sk)
913{
914 int cpu = raw_smp_processor_id();
915
916 if (unlikely(sk->sk_incoming_cpu != cpu))
917 sk->sk_incoming_cpu = cpu;
918}
919
920static inline void sock_rps_record_flow_hash(__u32 hash)
921{
922#ifdef CONFIG_RPS
923 struct rps_sock_flow_table *sock_flow_table;
924
925 rcu_read_lock();
926 sock_flow_table = rcu_dereference(rps_sock_flow_table);
927 rps_record_sock_flow(sock_flow_table, hash);
928 rcu_read_unlock();
929#endif
930}
931
932static inline void sock_rps_record_flow(const struct sock *sk)
933{
934#ifdef CONFIG_RPS
935 if (static_key_false(&rfs_needed)) {
936 /* Reading sk->sk_rxhash might incur an expensive cache line
937 * miss.
938 *
939 * TCP_ESTABLISHED does cover almost all states where RFS
940 * might be useful, and is cheaper [1] than testing :
941 * IPv4: inet_sk(sk)->inet_daddr
942 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
943 * OR an additional socket flag
944 * [1] : sk_state and sk_prot are in the same cache line.
945 */
946 if (sk->sk_state == TCP_ESTABLISHED)
947 sock_rps_record_flow_hash(sk->sk_rxhash);
948 }
949#endif
950}
951
952static inline void sock_rps_save_rxhash(struct sock *sk,
953 const struct sk_buff *skb)
954{
955#ifdef CONFIG_RPS
956 if (unlikely(sk->sk_rxhash != skb->hash))
957 sk->sk_rxhash = skb->hash;
958#endif
959}
960
961static inline void sock_rps_reset_rxhash(struct sock *sk)
962{
963#ifdef CONFIG_RPS
964 sk->sk_rxhash = 0;
965#endif
966}
967
968#define sk_wait_event(__sk, __timeo, __condition, __wait) \
969 ({ int __rc; \
970 release_sock(__sk); \
971 __rc = __condition; \
972 if (!__rc) { \
973 *(__timeo) = wait_woken(__wait, \
974 TASK_INTERRUPTIBLE, \
975 *(__timeo)); \
976 } \
977 sched_annotate_sleep(); \
978 lock_sock(__sk); \
979 __rc = __condition; \
980 __rc; \
981 })
982
983int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
984int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
985void sk_stream_wait_close(struct sock *sk, long timeo_p);
986int sk_stream_error(struct sock *sk, int flags, int err);
987void sk_stream_kill_queues(struct sock *sk);
988void sk_set_memalloc(struct sock *sk);
989void sk_clear_memalloc(struct sock *sk);
990
991void __sk_flush_backlog(struct sock *sk);
992
993static inline bool sk_flush_backlog(struct sock *sk)
994{
995 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
996 __sk_flush_backlog(sk);
997 return true;
998 }
999 return false;
1000}
1001
1002int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1003
1004struct request_sock_ops;
1005struct timewait_sock_ops;
1006struct inet_hashinfo;
1007struct raw_hashinfo;
1008struct smc_hashinfo;
1009struct module;
1010
1011/*
1012 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1013 * un-modified. Special care is taken when initializing object to zero.
1014 */
1015static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1016{
1017 if (offsetof(struct sock, sk_node.next) != 0)
1018 memset(sk, 0, offsetof(struct sock, sk_node.next));
1019 memset(&sk->sk_node.pprev, 0,
1020 size - offsetof(struct sock, sk_node.pprev));
1021}
1022
1023/* Networking protocol blocks we attach to sockets.
1024 * socket layer -> transport layer interface
1025 */
1026struct proto {
1027 void (*close)(struct sock *sk,
1028 long timeout);
1029 int (*pre_connect)(struct sock *sk,
1030 struct sockaddr *uaddr,
1031 int addr_len);
1032 int (*connect)(struct sock *sk,
1033 struct sockaddr *uaddr,
1034 int addr_len);
1035 int (*disconnect)(struct sock *sk, int flags);
1036
1037 struct sock * (*accept)(struct sock *sk, int flags, int *err,
1038 bool kern);
1039
1040 int (*ioctl)(struct sock *sk, int cmd,
1041 unsigned long arg);
1042 int (*init)(struct sock *sk);
1043 void (*destroy)(struct sock *sk);
1044 void (*shutdown)(struct sock *sk, int how);
1045 int (*setsockopt)(struct sock *sk, int level,
1046 int optname, char __user *optval,
1047 unsigned int optlen);
1048 int (*getsockopt)(struct sock *sk, int level,
1049 int optname, char __user *optval,
1050 int __user *option);
1051 void (*keepalive)(struct sock *sk, int valbool);
1052#ifdef CONFIG_COMPAT
1053 int (*compat_setsockopt)(struct sock *sk,
1054 int level,
1055 int optname, char __user *optval,
1056 unsigned int optlen);
1057 int (*compat_getsockopt)(struct sock *sk,
1058 int level,
1059 int optname, char __user *optval,
1060 int __user *option);
1061 int (*compat_ioctl)(struct sock *sk,
1062 unsigned int cmd, unsigned long arg);
1063#endif
1064 int (*sendmsg)(struct sock *sk, struct msghdr *msg,
1065 size_t len);
1066 int (*recvmsg)(struct sock *sk, struct msghdr *msg,
1067 size_t len, int noblock, int flags,
1068 int *addr_len);
1069 int (*sendpage)(struct sock *sk, struct page *page,
1070 int offset, size_t size, int flags);
1071 int (*bind)(struct sock *sk,
1072 struct sockaddr *uaddr, int addr_len);
1073
1074 int (*backlog_rcv) (struct sock *sk,
1075 struct sk_buff *skb);
1076
1077 void (*release_cb)(struct sock *sk);
1078
1079 /* Keeping track of sk's, looking them up, and port selection methods. */
1080 int (*hash)(struct sock *sk);
1081 void (*unhash)(struct sock *sk);
1082 void (*rehash)(struct sock *sk);
1083 int (*get_port)(struct sock *sk, unsigned short snum);
1084
1085 /* Keeping track of sockets in use */
1086#ifdef CONFIG_PROC_FS
1087 unsigned int inuse_idx;
1088#endif
1089
1090 bool (*stream_memory_free)(const struct sock *sk);
1091 bool (*stream_memory_read)(const struct sock *sk);
1092 /* Memory pressure */
1093 void (*enter_memory_pressure)(struct sock *sk);
1094 void (*leave_memory_pressure)(struct sock *sk);
1095 atomic_long_t *memory_allocated; /* Current allocated memory. */
1096 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1097 /*
1098 * Pressure flag: try to collapse.
1099 * Technical note: it is used by multiple contexts non atomically.
1100 * All the __sk_mem_schedule() is of this nature: accounting
1101 * is strict, actions are advisory and have some latency.
1102 */
1103 unsigned long *memory_pressure;
1104 long *sysctl_mem;
1105
1106 int *sysctl_wmem;
1107 int *sysctl_rmem;
1108 u32 sysctl_wmem_offset;
1109 u32 sysctl_rmem_offset;
1110
1111 int max_header;
1112 bool no_autobind;
1113
1114 struct kmem_cache *slab;
1115 unsigned int obj_size;
1116 slab_flags_t slab_flags;
1117 unsigned int useroffset; /* Usercopy region offset */
1118 unsigned int usersize; /* Usercopy region size */
1119
1120 struct percpu_counter *orphan_count;
1121
1122 struct request_sock_ops *rsk_prot;
1123 struct timewait_sock_ops *twsk_prot;
1124
1125 union {
1126 struct inet_hashinfo *hashinfo;
1127 struct udp_table *udp_table;
1128 struct raw_hashinfo *raw_hash;
1129 struct smc_hashinfo *smc_hash;
1130 } h;
1131
1132 struct module *owner;
1133
1134 char name[32];
1135
1136 struct list_head node;
1137#ifdef SOCK_REFCNT_DEBUG
1138 atomic_t socks;
1139#endif
1140 int (*diag_destroy)(struct sock *sk, int err);
1141} __randomize_layout;
1142
1143int proto_register(struct proto *prot, int alloc_slab);
1144void proto_unregister(struct proto *prot);
1145int sock_load_diag_module(int family, int protocol);
1146
1147#ifdef SOCK_REFCNT_DEBUG
1148static inline void sk_refcnt_debug_inc(struct sock *sk)
1149{
1150 atomic_inc(&sk->sk_prot->socks);
1151}
1152
1153static inline void sk_refcnt_debug_dec(struct sock *sk)
1154{
1155 atomic_dec(&sk->sk_prot->socks);
1156 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1157 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1158}
1159
1160static inline void sk_refcnt_debug_release(const struct sock *sk)
1161{
1162 if (refcount_read(&sk->sk_refcnt) != 1)
1163 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1164 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1165}
1166#else /* SOCK_REFCNT_DEBUG */
1167#define sk_refcnt_debug_inc(sk) do { } while (0)
1168#define sk_refcnt_debug_dec(sk) do { } while (0)
1169#define sk_refcnt_debug_release(sk) do { } while (0)
1170#endif /* SOCK_REFCNT_DEBUG */
1171
1172static inline bool sk_stream_memory_free(const struct sock *sk)
1173{
1174 if (sk->sk_wmem_queued >= sk->sk_sndbuf)
1175 return false;
1176
1177 return sk->sk_prot->stream_memory_free ?
1178 sk->sk_prot->stream_memory_free(sk) : true;
1179}
1180
1181static inline bool sk_stream_is_writeable(const struct sock *sk)
1182{
1183 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1184 sk_stream_memory_free(sk);
1185}
1186
1187static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1188 struct cgroup *ancestor)
1189{
1190#ifdef CONFIG_SOCK_CGROUP_DATA
1191 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1192 ancestor);
1193#else
1194 return -ENOTSUPP;
1195#endif
1196}
1197
1198static inline bool sk_has_memory_pressure(const struct sock *sk)
1199{
1200 return sk->sk_prot->memory_pressure != NULL;
1201}
1202
1203static inline bool sk_under_memory_pressure(const struct sock *sk)
1204{
1205 if (!sk->sk_prot->memory_pressure)
1206 return false;
1207
1208 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1209 mem_cgroup_under_socket_pressure(sk->sk_memcg))
1210 return true;
1211
1212 return !!*sk->sk_prot->memory_pressure;
1213}
1214
1215static inline long
1216sk_memory_allocated(const struct sock *sk)
1217{
1218 return atomic_long_read(sk->sk_prot->memory_allocated);
1219}
1220
1221static inline long
1222sk_memory_allocated_add(struct sock *sk, int amt)
1223{
1224 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1225}
1226
1227static inline void
1228sk_memory_allocated_sub(struct sock *sk, int amt)
1229{
1230 atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1231}
1232
1233static inline void sk_sockets_allocated_dec(struct sock *sk)
1234{
1235 percpu_counter_dec(sk->sk_prot->sockets_allocated);
1236}
1237
1238static inline void sk_sockets_allocated_inc(struct sock *sk)
1239{
1240 percpu_counter_inc(sk->sk_prot->sockets_allocated);
1241}
1242
1243static inline int
1244sk_sockets_allocated_read_positive(struct sock *sk)
1245{
1246 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1247}
1248
1249static inline int
1250proto_sockets_allocated_sum_positive(struct proto *prot)
1251{
1252 return percpu_counter_sum_positive(prot->sockets_allocated);
1253}
1254
1255static inline long
1256proto_memory_allocated(struct proto *prot)
1257{
1258 return atomic_long_read(prot->memory_allocated);
1259}
1260
1261static inline bool
1262proto_memory_pressure(struct proto *prot)
1263{
1264 if (!prot->memory_pressure)
1265 return false;
1266 return !!*prot->memory_pressure;
1267}
1268
1269
1270#ifdef CONFIG_PROC_FS
1271/* Called with local bh disabled */
1272void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1273int sock_prot_inuse_get(struct net *net, struct proto *proto);
1274int sock_inuse_get(struct net *net);
1275#else
1276static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1277 int inc)
1278{
1279}
1280#endif
1281
1282
1283/* With per-bucket locks this operation is not-atomic, so that
1284 * this version is not worse.
1285 */
1286static inline int __sk_prot_rehash(struct sock *sk)
1287{
1288 sk->sk_prot->unhash(sk);
1289 return sk->sk_prot->hash(sk);
1290}
1291
1292/* About 10 seconds */
1293#define SOCK_DESTROY_TIME (10*HZ)
1294
1295/* Sockets 0-1023 can't be bound to unless you are superuser */
1296#define PROT_SOCK 1024
1297
1298#define SHUTDOWN_MASK 3
1299#define RCV_SHUTDOWN 1
1300#define SEND_SHUTDOWN 2
1301
1302#define SOCK_SNDBUF_LOCK 1
1303#define SOCK_RCVBUF_LOCK 2
1304#define SOCK_BINDADDR_LOCK 4
1305#define SOCK_BINDPORT_LOCK 8
1306
1307struct socket_alloc {
1308 struct socket socket;
1309 struct inode vfs_inode;
1310};
1311
1312static inline struct socket *SOCKET_I(struct inode *inode)
1313{
1314 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1315}
1316
1317static inline struct inode *SOCK_INODE(struct socket *socket)
1318{
1319 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1320}
1321
1322/*
1323 * Functions for memory accounting
1324 */
1325int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1326int __sk_mem_schedule(struct sock *sk, int size, int kind);
1327void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1328void __sk_mem_reclaim(struct sock *sk, int amount);
1329
1330/* We used to have PAGE_SIZE here, but systems with 64KB pages
1331 * do not necessarily have 16x time more memory than 4KB ones.
1332 */
1333#define SK_MEM_QUANTUM 4096
1334#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1335#define SK_MEM_SEND 0
1336#define SK_MEM_RECV 1
1337
1338/* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
1339static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1340{
1341 long val = sk->sk_prot->sysctl_mem[index];
1342
1343#if PAGE_SIZE > SK_MEM_QUANTUM
1344 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1345#elif PAGE_SIZE < SK_MEM_QUANTUM
1346 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1347#endif
1348 return val;
1349}
1350
1351static inline int sk_mem_pages(int amt)
1352{
1353 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1354}
1355
1356static inline bool sk_has_account(struct sock *sk)
1357{
1358 /* return true if protocol supports memory accounting */
1359 return !!sk->sk_prot->memory_allocated;
1360}
1361
1362static inline bool sk_wmem_schedule(struct sock *sk, int size)
1363{
1364 if (!sk_has_account(sk))
1365 return true;
1366 return size <= sk->sk_forward_alloc ||
1367 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1368}
1369
1370static inline bool
1371sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1372{
1373 if (!sk_has_account(sk))
1374 return true;
1375 return size<= sk->sk_forward_alloc ||
1376 __sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1377 skb_pfmemalloc(skb);
1378}
1379
1380static inline void sk_mem_reclaim(struct sock *sk)
1381{
1382 if (!sk_has_account(sk))
1383 return;
1384 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1385 __sk_mem_reclaim(sk, sk->sk_forward_alloc);
1386}
1387
1388static inline void sk_mem_reclaim_partial(struct sock *sk)
1389{
1390 if (!sk_has_account(sk))
1391 return;
1392 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1393 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1394}
1395
1396static inline void sk_mem_charge(struct sock *sk, int size)
1397{
1398 if (!sk_has_account(sk))
1399 return;
1400 sk->sk_forward_alloc -= size;
1401}
1402
1403static inline void sk_mem_uncharge(struct sock *sk, int size)
1404{
1405 if (!sk_has_account(sk))
1406 return;
1407 sk->sk_forward_alloc += size;
1408
1409 /* Avoid a possible overflow.
1410 * TCP send queues can make this happen, if sk_mem_reclaim()
1411 * is not called and more than 2 GBytes are released at once.
1412 *
1413 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1414 * no need to hold that much forward allocation anyway.
1415 */
1416 if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1417 __sk_mem_reclaim(sk, 1 << 20);
1418}
1419
1420static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1421{
1422 sock_set_flag(sk, SOCK_QUEUE_SHRUNK);
1423 sk->sk_wmem_queued -= skb->truesize;
1424 sk_mem_uncharge(sk, skb->truesize);
1425 __kfree_skb(skb);
1426}
1427
1428static inline void sock_release_ownership(struct sock *sk)
1429{
1430 if (sk->sk_lock.owned) {
1431 sk->sk_lock.owned = 0;
1432
1433 /* The sk_lock has mutex_unlock() semantics: */
1434 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
1435 }
1436}
1437
1438/*
1439 * Macro so as to not evaluate some arguments when
1440 * lockdep is not enabled.
1441 *
1442 * Mark both the sk_lock and the sk_lock.slock as a
1443 * per-address-family lock class.
1444 */
1445#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1446do { \
1447 sk->sk_lock.owned = 0; \
1448 init_waitqueue_head(&sk->sk_lock.wq); \
1449 spin_lock_init(&(sk)->sk_lock.slock); \
1450 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1451 sizeof((sk)->sk_lock)); \
1452 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1453 (skey), (sname)); \
1454 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1455} while (0)
1456
1457#ifdef CONFIG_LOCKDEP
1458static inline bool lockdep_sock_is_held(const struct sock *sk)
1459{
1460 return lockdep_is_held(&sk->sk_lock) ||
1461 lockdep_is_held(&sk->sk_lock.slock);
1462}
1463#endif
1464
1465void lock_sock_nested(struct sock *sk, int subclass);
1466
1467static inline void lock_sock(struct sock *sk)
1468{
1469 lock_sock_nested(sk, 0);
1470}
1471
1472void release_sock(struct sock *sk);
1473
1474/* BH context may only use the following locking interface. */
1475#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1476#define bh_lock_sock_nested(__sk) \
1477 spin_lock_nested(&((__sk)->sk_lock.slock), \
1478 SINGLE_DEPTH_NESTING)
1479#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1480
1481bool lock_sock_fast(struct sock *sk);
1482/**
1483 * unlock_sock_fast - complement of lock_sock_fast
1484 * @sk: socket
1485 * @slow: slow mode
1486 *
1487 * fast unlock socket for user context.
1488 * If slow mode is on, we call regular release_sock()
1489 */
1490static inline void unlock_sock_fast(struct sock *sk, bool slow)
1491{
1492 if (slow)
1493 release_sock(sk);
1494 else
1495 spin_unlock_bh(&sk->sk_lock.slock);
1496}
1497
1498/* Used by processes to "lock" a socket state, so that
1499 * interrupts and bottom half handlers won't change it
1500 * from under us. It essentially blocks any incoming
1501 * packets, so that we won't get any new data or any
1502 * packets that change the state of the socket.
1503 *
1504 * While locked, BH processing will add new packets to
1505 * the backlog queue. This queue is processed by the
1506 * owner of the socket lock right before it is released.
1507 *
1508 * Since ~2.3.5 it is also exclusive sleep lock serializing
1509 * accesses from user process context.
1510 */
1511
1512static inline void sock_owned_by_me(const struct sock *sk)
1513{
1514#ifdef CONFIG_LOCKDEP
1515 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1516#endif
1517}
1518
1519static inline bool sock_owned_by_user(const struct sock *sk)
1520{
1521 sock_owned_by_me(sk);
1522 return sk->sk_lock.owned;
1523}
1524
1525static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1526{
1527 return sk->sk_lock.owned;
1528}
1529
1530/* no reclassification while locks are held */
1531static inline bool sock_allow_reclassification(const struct sock *csk)
1532{
1533 struct sock *sk = (struct sock *)csk;
1534
1535 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
1536}
1537
1538struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1539 struct proto *prot, int kern);
1540void sk_free(struct sock *sk);
1541void sk_destruct(struct sock *sk);
1542struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1543void sk_free_unlock_clone(struct sock *sk);
1544
1545struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1546 gfp_t priority);
1547void __sock_wfree(struct sk_buff *skb);
1548void sock_wfree(struct sk_buff *skb);
1549struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1550 gfp_t priority);
1551void skb_orphan_partial(struct sk_buff *skb);
1552void sock_rfree(struct sk_buff *skb);
1553void sock_efree(struct sk_buff *skb);
1554#ifdef CONFIG_INET
1555void sock_edemux(struct sk_buff *skb);
1556#else
1557#define sock_edemux sock_efree
1558#endif
1559
1560int sock_setsockopt(struct socket *sock, int level, int op,
1561 char __user *optval, unsigned int optlen);
1562
1563int sock_getsockopt(struct socket *sock, int level, int op,
1564 char __user *optval, int __user *optlen);
1565struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1566 int noblock, int *errcode);
1567struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1568 unsigned long data_len, int noblock,
1569 int *errcode, int max_page_order);
1570void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1571void sock_kfree_s(struct sock *sk, void *mem, int size);
1572void sock_kzfree_s(struct sock *sk, void *mem, int size);
1573void sk_send_sigurg(struct sock *sk);
1574
1575struct sockcm_cookie {
1576 u32 mark;
1577 u16 tsflags;
1578};
1579
1580int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1581 struct sockcm_cookie *sockc);
1582int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1583 struct sockcm_cookie *sockc);
1584
1585/*
1586 * Functions to fill in entries in struct proto_ops when a protocol
1587 * does not implement a particular function.
1588 */
1589int sock_no_bind(struct socket *, struct sockaddr *, int);
1590int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1591int sock_no_socketpair(struct socket *, struct socket *);
1592int sock_no_accept(struct socket *, struct socket *, int, bool);
1593int sock_no_getname(struct socket *, struct sockaddr *, int);
1594__poll_t sock_no_poll(struct file *, struct socket *,
1595 struct poll_table_struct *);
1596int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1597int sock_no_listen(struct socket *, int);
1598int sock_no_shutdown(struct socket *, int);
1599int sock_no_getsockopt(struct socket *, int , int, char __user *, int __user *);
1600int sock_no_setsockopt(struct socket *, int, int, char __user *, unsigned int);
1601int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1602int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1603int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1604int sock_no_mmap(struct file *file, struct socket *sock,
1605 struct vm_area_struct *vma);
1606ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1607 size_t size, int flags);
1608ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1609 int offset, size_t size, int flags);
1610
1611/*
1612 * Functions to fill in entries in struct proto_ops when a protocol
1613 * uses the inet style.
1614 */
1615int sock_common_getsockopt(struct socket *sock, int level, int optname,
1616 char __user *optval, int __user *optlen);
1617int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1618 int flags);
1619int sock_common_setsockopt(struct socket *sock, int level, int optname,
1620 char __user *optval, unsigned int optlen);
1621int compat_sock_common_getsockopt(struct socket *sock, int level,
1622 int optname, char __user *optval, int __user *optlen);
1623int compat_sock_common_setsockopt(struct socket *sock, int level,
1624 int optname, char __user *optval, unsigned int optlen);
1625
1626void sk_common_release(struct sock *sk);
1627
1628/*
1629 * Default socket callbacks and setup code
1630 */
1631
1632/* Initialise core socket variables */
1633void sock_init_data(struct socket *sock, struct sock *sk);
1634
1635/*
1636 * Socket reference counting postulates.
1637 *
1638 * * Each user of socket SHOULD hold a reference count.
1639 * * Each access point to socket (an hash table bucket, reference from a list,
1640 * running timer, skb in flight MUST hold a reference count.
1641 * * When reference count hits 0, it means it will never increase back.
1642 * * When reference count hits 0, it means that no references from
1643 * outside exist to this socket and current process on current CPU
1644 * is last user and may/should destroy this socket.
1645 * * sk_free is called from any context: process, BH, IRQ. When
1646 * it is called, socket has no references from outside -> sk_free
1647 * may release descendant resources allocated by the socket, but
1648 * to the time when it is called, socket is NOT referenced by any
1649 * hash tables, lists etc.
1650 * * Packets, delivered from outside (from network or from another process)
1651 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1652 * when they sit in queue. Otherwise, packets will leak to hole, when
1653 * socket is looked up by one cpu and unhasing is made by another CPU.
1654 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1655 * (leak to backlog). Packet socket does all the processing inside
1656 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1657 * use separate SMP lock, so that they are prone too.
1658 */
1659
1660/* Ungrab socket and destroy it, if it was the last reference. */
1661static inline void sock_put(struct sock *sk)
1662{
1663 if (refcount_dec_and_test(&sk->sk_refcnt))
1664 sk_free(sk);
1665}
1666/* Generic version of sock_put(), dealing with all sockets
1667 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1668 */
1669void sock_gen_put(struct sock *sk);
1670
1671int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1672 unsigned int trim_cap, bool refcounted);
1673static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1674 const int nested)
1675{
1676 return __sk_receive_skb(sk, skb, nested, 1, true);
1677}
1678
1679static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1680{
1681 sk->sk_tx_queue_mapping = tx_queue;
1682}
1683
1684static inline void sk_tx_queue_clear(struct sock *sk)
1685{
1686 sk->sk_tx_queue_mapping = -1;
1687}
1688
1689static inline int sk_tx_queue_get(const struct sock *sk)
1690{
1691 return sk ? sk->sk_tx_queue_mapping : -1;
1692}
1693
1694static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1695{
1696 sk_tx_queue_clear(sk);
1697 sk->sk_socket = sock;
1698}
1699
1700static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1701{
1702 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1703 return &rcu_dereference_raw(sk->sk_wq)->wait;
1704}
1705/* Detach socket from process context.
1706 * Announce socket dead, detach it from wait queue and inode.
1707 * Note that parent inode held reference count on this struct sock,
1708 * we do not release it in this function, because protocol
1709 * probably wants some additional cleanups or even continuing
1710 * to work with this socket (TCP).
1711 */
1712static inline void sock_orphan(struct sock *sk)
1713{
1714 write_lock_bh(&sk->sk_callback_lock);
1715 sock_set_flag(sk, SOCK_DEAD);
1716 sk_set_socket(sk, NULL);
1717 sk->sk_wq = NULL;
1718 write_unlock_bh(&sk->sk_callback_lock);
1719}
1720
1721static inline void sock_graft(struct sock *sk, struct socket *parent)
1722{
1723 WARN_ON(parent->sk);
1724 write_lock_bh(&sk->sk_callback_lock);
1725 sk->sk_wq = parent->wq;
1726 parent->sk = sk;
1727 sk_set_socket(sk, parent);
1728 sk->sk_uid = SOCK_INODE(parent)->i_uid;
1729 security_sock_graft(sk, parent);
1730 write_unlock_bh(&sk->sk_callback_lock);
1731}
1732
1733kuid_t sock_i_uid(struct sock *sk);
1734unsigned long sock_i_ino(struct sock *sk);
1735
1736static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
1737{
1738 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
1739}
1740
1741static inline u32 net_tx_rndhash(void)
1742{
1743 u32 v = prandom_u32();
1744
1745 return v ?: 1;
1746}
1747
1748static inline void sk_set_txhash(struct sock *sk)
1749{
1750 sk->sk_txhash = net_tx_rndhash();
1751}
1752
1753static inline void sk_rethink_txhash(struct sock *sk)
1754{
1755 if (sk->sk_txhash)
1756 sk_set_txhash(sk);
1757}
1758
1759static inline struct dst_entry *
1760__sk_dst_get(struct sock *sk)
1761{
1762 return rcu_dereference_check(sk->sk_dst_cache,
1763 lockdep_sock_is_held(sk));
1764}
1765
1766static inline struct dst_entry *
1767sk_dst_get(struct sock *sk)
1768{
1769 struct dst_entry *dst;
1770
1771 rcu_read_lock();
1772 dst = rcu_dereference(sk->sk_dst_cache);
1773 if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1774 dst = NULL;
1775 rcu_read_unlock();
1776 return dst;
1777}
1778
1779static inline void dst_negative_advice(struct sock *sk)
1780{
1781 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1782
1783 sk_rethink_txhash(sk);
1784
1785 if (dst && dst->ops->negative_advice) {
1786 ndst = dst->ops->negative_advice(dst);
1787
1788 if (ndst != dst) {
1789 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1790 sk_tx_queue_clear(sk);
1791 sk->sk_dst_pending_confirm = 0;
1792 }
1793 }
1794}
1795
1796static inline void
1797__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1798{
1799 struct dst_entry *old_dst;
1800
1801 sk_tx_queue_clear(sk);
1802 sk->sk_dst_pending_confirm = 0;
1803 old_dst = rcu_dereference_protected(sk->sk_dst_cache,
1804 lockdep_sock_is_held(sk));
1805 rcu_assign_pointer(sk->sk_dst_cache, dst);
1806 dst_release(old_dst);
1807}
1808
1809static inline void
1810sk_dst_set(struct sock *sk, struct dst_entry *dst)
1811{
1812 struct dst_entry *old_dst;
1813
1814 sk_tx_queue_clear(sk);
1815 sk->sk_dst_pending_confirm = 0;
1816 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
1817 dst_release(old_dst);
1818}
1819
1820static inline void
1821__sk_dst_reset(struct sock *sk)
1822{
1823 __sk_dst_set(sk, NULL);
1824}
1825
1826static inline void
1827sk_dst_reset(struct sock *sk)
1828{
1829 sk_dst_set(sk, NULL);
1830}
1831
1832struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
1833
1834struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
1835
1836static inline void sk_dst_confirm(struct sock *sk)
1837{
1838 if (!sk->sk_dst_pending_confirm)
1839 sk->sk_dst_pending_confirm = 1;
1840}
1841
1842static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
1843{
1844 if (skb_get_dst_pending_confirm(skb)) {
1845 struct sock *sk = skb->sk;
1846 unsigned long now = jiffies;
1847
1848 /* avoid dirtying neighbour */
1849 if (n->confirmed != now)
1850 n->confirmed = now;
1851 if (sk && sk->sk_dst_pending_confirm)
1852 sk->sk_dst_pending_confirm = 0;
1853 }
1854}
1855
1856bool sk_mc_loop(struct sock *sk);
1857
1858static inline bool sk_can_gso(const struct sock *sk)
1859{
1860 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
1861}
1862
1863void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
1864
1865static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
1866{
1867 sk->sk_route_nocaps |= flags;
1868 sk->sk_route_caps &= ~flags;
1869}
1870
1871static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
1872 struct iov_iter *from, char *to,
1873 int copy, int offset)
1874{
1875 if (skb->ip_summed == CHECKSUM_NONE) {
1876 __wsum csum = 0;
1877 if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
1878 return -EFAULT;
1879 skb->csum = csum_block_add(skb->csum, csum, offset);
1880 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
1881 if (!copy_from_iter_full_nocache(to, copy, from))
1882 return -EFAULT;
1883 } else if (!copy_from_iter_full(to, copy, from))
1884 return -EFAULT;
1885
1886 return 0;
1887}
1888
1889static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
1890 struct iov_iter *from, int copy)
1891{
1892 int err, offset = skb->len;
1893
1894 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
1895 copy, offset);
1896 if (err)
1897 __skb_trim(skb, offset);
1898
1899 return err;
1900}
1901
1902static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
1903 struct sk_buff *skb,
1904 struct page *page,
1905 int off, int copy)
1906{
1907 int err;
1908
1909 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
1910 copy, skb->len);
1911 if (err)
1912 return err;
1913
1914 skb->len += copy;
1915 skb->data_len += copy;
1916 skb->truesize += copy;
1917 sk->sk_wmem_queued += copy;
1918 sk_mem_charge(sk, copy);
1919 return 0;
1920}
1921
1922/**
1923 * sk_wmem_alloc_get - returns write allocations
1924 * @sk: socket
1925 *
1926 * Returns sk_wmem_alloc minus initial offset of one
1927 */
1928static inline int sk_wmem_alloc_get(const struct sock *sk)
1929{
1930 return refcount_read(&sk->sk_wmem_alloc) - 1;
1931}
1932
1933/**
1934 * sk_rmem_alloc_get - returns read allocations
1935 * @sk: socket
1936 *
1937 * Returns sk_rmem_alloc
1938 */
1939static inline int sk_rmem_alloc_get(const struct sock *sk)
1940{
1941 return atomic_read(&sk->sk_rmem_alloc);
1942}
1943
1944/**
1945 * sk_has_allocations - check if allocations are outstanding
1946 * @sk: socket
1947 *
1948 * Returns true if socket has write or read allocations
1949 */
1950static inline bool sk_has_allocations(const struct sock *sk)
1951{
1952 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
1953}
1954
1955/**
1956 * skwq_has_sleeper - check if there are any waiting processes
1957 * @wq: struct socket_wq
1958 *
1959 * Returns true if socket_wq has waiting processes
1960 *
1961 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
1962 * barrier call. They were added due to the race found within the tcp code.
1963 *
1964 * Consider following tcp code paths::
1965 *
1966 * CPU1 CPU2
1967 * sys_select receive packet
1968 * ... ...
1969 * __add_wait_queue update tp->rcv_nxt
1970 * ... ...
1971 * tp->rcv_nxt check sock_def_readable
1972 * ... {
1973 * schedule rcu_read_lock();
1974 * wq = rcu_dereference(sk->sk_wq);
1975 * if (wq && waitqueue_active(&wq->wait))
1976 * wake_up_interruptible(&wq->wait)
1977 * ...
1978 * }
1979 *
1980 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
1981 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
1982 * could then endup calling schedule and sleep forever if there are no more
1983 * data on the socket.
1984 *
1985 */
1986static inline bool skwq_has_sleeper(struct socket_wq *wq)
1987{
1988 return wq && wq_has_sleeper(&wq->wait);
1989}
1990
1991/**
1992 * sock_poll_wait - place memory barrier behind the poll_wait call.
1993 * @filp: file
1994 * @wait_address: socket wait queue
1995 * @p: poll_table
1996 *
1997 * See the comments in the wq_has_sleeper function.
1998 */
1999static inline void sock_poll_wait(struct file *filp,
2000 wait_queue_head_t *wait_address, poll_table *p)
2001{
2002 if (!poll_does_not_wait(p) && wait_address) {
2003 poll_wait(filp, wait_address, p);
2004 /* We need to be sure we are in sync with the
2005 * socket flags modification.
2006 *
2007 * This memory barrier is paired in the wq_has_sleeper.
2008 */
2009 smp_mb();
2010 }
2011}
2012
2013static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2014{
2015 if (sk->sk_txhash) {
2016 skb->l4_hash = 1;
2017 skb->hash = sk->sk_txhash;
2018 }
2019}
2020
2021void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2022
2023/*
2024 * Queue a received datagram if it will fit. Stream and sequenced
2025 * protocols can't normally use this as they need to fit buffers in
2026 * and play with them.
2027 *
2028 * Inlined as it's very short and called for pretty much every
2029 * packet ever received.
2030 */
2031static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2032{
2033 skb_orphan(skb);
2034 skb->sk = sk;
2035 skb->destructor = sock_rfree;
2036 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2037 sk_mem_charge(sk, skb->truesize);
2038}
2039
2040void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2041 unsigned long expires);
2042
2043void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2044
2045int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2046 struct sk_buff *skb, unsigned int flags,
2047 void (*destructor)(struct sock *sk,
2048 struct sk_buff *skb));
2049int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2050int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2051
2052int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2053struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2054
2055/*
2056 * Recover an error report and clear atomically
2057 */
2058
2059static inline int sock_error(struct sock *sk)
2060{
2061 int err;
2062 if (likely(!sk->sk_err))
2063 return 0;
2064 err = xchg(&sk->sk_err, 0);
2065 return -err;
2066}
2067
2068static inline unsigned long sock_wspace(struct sock *sk)
2069{
2070 int amt = 0;
2071
2072 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2073 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2074 if (amt < 0)
2075 amt = 0;
2076 }
2077 return amt;
2078}
2079
2080/* Note:
2081 * We use sk->sk_wq_raw, from contexts knowing this
2082 * pointer is not NULL and cannot disappear/change.
2083 */
2084static inline void sk_set_bit(int nr, struct sock *sk)
2085{
2086 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2087 !sock_flag(sk, SOCK_FASYNC))
2088 return;
2089
2090 set_bit(nr, &sk->sk_wq_raw->flags);
2091}
2092
2093static inline void sk_clear_bit(int nr, struct sock *sk)
2094{
2095 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2096 !sock_flag(sk, SOCK_FASYNC))
2097 return;
2098
2099 clear_bit(nr, &sk->sk_wq_raw->flags);
2100}
2101
2102static inline void sk_wake_async(const struct sock *sk, int how, int band)
2103{
2104 if (sock_flag(sk, SOCK_FASYNC)) {
2105 rcu_read_lock();
2106 sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2107 rcu_read_unlock();
2108 }
2109}
2110
2111/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2112 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2113 * Note: for send buffers, TCP works better if we can build two skbs at
2114 * minimum.
2115 */
2116#define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2117
2118#define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2119#define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2120
2121static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2122{
2123 if (!(sk->sk_userlocks & SOCK_SNDBUF_LOCK)) {
2124 sk->sk_sndbuf = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2125 sk->sk_sndbuf = max_t(u32, sk->sk_sndbuf, SOCK_MIN_SNDBUF);
2126 }
2127}
2128
2129struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2130 bool force_schedule);
2131
2132/**
2133 * sk_page_frag - return an appropriate page_frag
2134 * @sk: socket
2135 *
2136 * If socket allocation mode allows current thread to sleep, it means its
2137 * safe to use the per task page_frag instead of the per socket one.
2138 */
2139static inline struct page_frag *sk_page_frag(struct sock *sk)
2140{
2141 if (gfpflags_allow_blocking(sk->sk_allocation))
2142 return ¤t->task_frag;
2143
2144 return &sk->sk_frag;
2145}
2146
2147bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2148
2149int sk_alloc_sg(struct sock *sk, int len, struct scatterlist *sg,
2150 int sg_start, int *sg_curr, unsigned int *sg_size,
2151 int first_coalesce);
2152
2153/*
2154 * Default write policy as shown to user space via poll/select/SIGIO
2155 */
2156static inline bool sock_writeable(const struct sock *sk)
2157{
2158 return refcount_read(&sk->sk_wmem_alloc) < (sk->sk_sndbuf >> 1);
2159}
2160
2161static inline gfp_t gfp_any(void)
2162{
2163 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2164}
2165
2166static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2167{
2168 return noblock ? 0 : sk->sk_rcvtimeo;
2169}
2170
2171static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2172{
2173 return noblock ? 0 : sk->sk_sndtimeo;
2174}
2175
2176static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2177{
2178 return (waitall ? len : min_t(int, sk->sk_rcvlowat, len)) ? : 1;
2179}
2180
2181/* Alas, with timeout socket operations are not restartable.
2182 * Compare this to poll().
2183 */
2184static inline int sock_intr_errno(long timeo)
2185{
2186 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2187}
2188
2189struct sock_skb_cb {
2190 u32 dropcount;
2191};
2192
2193/* Store sock_skb_cb at the end of skb->cb[] so protocol families
2194 * using skb->cb[] would keep using it directly and utilize its
2195 * alignement guarantee.
2196 */
2197#define SOCK_SKB_CB_OFFSET ((FIELD_SIZEOF(struct sk_buff, cb) - \
2198 sizeof(struct sock_skb_cb)))
2199
2200#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2201 SOCK_SKB_CB_OFFSET))
2202
2203#define sock_skb_cb_check_size(size) \
2204 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2205
2206static inline void
2207sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2208{
2209 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2210 atomic_read(&sk->sk_drops) : 0;
2211}
2212
2213static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2214{
2215 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2216
2217 atomic_add(segs, &sk->sk_drops);
2218}
2219
2220void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2221 struct sk_buff *skb);
2222void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2223 struct sk_buff *skb);
2224
2225static inline void
2226sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2227{
2228 ktime_t kt = skb->tstamp;
2229 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2230
2231 /*
2232 * generate control messages if
2233 * - receive time stamping in software requested
2234 * - software time stamp available and wanted
2235 * - hardware time stamps available and wanted
2236 */
2237 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2238 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2239 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2240 (hwtstamps->hwtstamp &&
2241 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2242 __sock_recv_timestamp(msg, sk, skb);
2243 else
2244 sk->sk_stamp = kt;
2245
2246 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2247 __sock_recv_wifi_status(msg, sk, skb);
2248}
2249
2250void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2251 struct sk_buff *skb);
2252
2253#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2254static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2255 struct sk_buff *skb)
2256{
2257#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2258 (1UL << SOCK_RCVTSTAMP))
2259#define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2260 SOF_TIMESTAMPING_RAW_HARDWARE)
2261
2262 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2263 __sock_recv_ts_and_drops(msg, sk, skb);
2264 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2265 sk->sk_stamp = skb->tstamp;
2266 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
2267 sk->sk_stamp = 0;
2268}
2269
2270void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2271
2272/**
2273 * sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2274 * @sk: socket sending this packet
2275 * @tsflags: timestamping flags to use
2276 * @tx_flags: completed with instructions for time stamping
2277 *
2278 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2279 */
2280static inline void sock_tx_timestamp(const struct sock *sk, __u16 tsflags,
2281 __u8 *tx_flags)
2282{
2283 if (unlikely(tsflags))
2284 __sock_tx_timestamp(tsflags, tx_flags);
2285 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2286 *tx_flags |= SKBTX_WIFI_STATUS;
2287}
2288
2289/**
2290 * sk_eat_skb - Release a skb if it is no longer needed
2291 * @sk: socket to eat this skb from
2292 * @skb: socket buffer to eat
2293 *
2294 * This routine must be called with interrupts disabled or with the socket
2295 * locked so that the sk_buff queue operation is ok.
2296*/
2297static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2298{
2299 __skb_unlink(skb, &sk->sk_receive_queue);
2300 __kfree_skb(skb);
2301}
2302
2303static inline
2304struct net *sock_net(const struct sock *sk)
2305{
2306 return read_pnet(&sk->sk_net);
2307}
2308
2309static inline
2310void sock_net_set(struct sock *sk, struct net *net)
2311{
2312 write_pnet(&sk->sk_net, net);
2313}
2314
2315static inline struct sock *skb_steal_sock(struct sk_buff *skb)
2316{
2317 if (skb->sk) {
2318 struct sock *sk = skb->sk;
2319
2320 skb->destructor = NULL;
2321 skb->sk = NULL;
2322 return sk;
2323 }
2324 return NULL;
2325}
2326
2327/* This helper checks if a socket is a full socket,
2328 * ie _not_ a timewait or request socket.
2329 */
2330static inline bool sk_fullsock(const struct sock *sk)
2331{
2332 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2333}
2334
2335/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2336 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2337 */
2338static inline bool sk_listener(const struct sock *sk)
2339{
2340 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2341}
2342
2343void sock_enable_timestamp(struct sock *sk, int flag);
2344int sock_get_timestamp(struct sock *, struct timeval __user *);
2345int sock_get_timestampns(struct sock *, struct timespec __user *);
2346int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2347 int type);
2348
2349bool sk_ns_capable(const struct sock *sk,
2350 struct user_namespace *user_ns, int cap);
2351bool sk_capable(const struct sock *sk, int cap);
2352bool sk_net_capable(const struct sock *sk, int cap);
2353
2354void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2355
2356/* Take into consideration the size of the struct sk_buff overhead in the
2357 * determination of these values, since that is non-constant across
2358 * platforms. This makes socket queueing behavior and performance
2359 * not depend upon such differences.
2360 */
2361#define _SK_MEM_PACKETS 256
2362#define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
2363#define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2364#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2365
2366extern __u32 sysctl_wmem_max;
2367extern __u32 sysctl_rmem_max;
2368
2369extern int sysctl_tstamp_allow_data;
2370extern int sysctl_optmem_max;
2371
2372extern __u32 sysctl_wmem_default;
2373extern __u32 sysctl_rmem_default;
2374
2375static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2376{
2377 /* Does this proto have per netns sysctl_wmem ? */
2378 if (proto->sysctl_wmem_offset)
2379 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset);
2380
2381 return *proto->sysctl_wmem;
2382}
2383
2384static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2385{
2386 /* Does this proto have per netns sysctl_rmem ? */
2387 if (proto->sysctl_rmem_offset)
2388 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset);
2389
2390 return *proto->sysctl_rmem;
2391}
2392
2393/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2394 * Some wifi drivers need to tweak it to get more chunks.
2395 * They can use this helper from their ndo_start_xmit()
2396 */
2397static inline void sk_pacing_shift_update(struct sock *sk, int val)
2398{
2399 if (!sk || !sk_fullsock(sk) || sk->sk_pacing_shift == val)
2400 return;
2401 sk->sk_pacing_shift = val;
2402}
2403
2404/* if a socket is bound to a device, check that the given device
2405 * index is either the same or that the socket is bound to an L3
2406 * master device and the given device index is also enslaved to
2407 * that L3 master
2408 */
2409static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2410{
2411 int mdif;
2412
2413 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
2414 return true;
2415
2416 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2417 if (mdif && mdif == sk->sk_bound_dev_if)
2418 return true;
2419
2420 return false;
2421}
2422
2423#endif /* _SOCK_H */
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Definitions for the AF_INET socket handler.
8 *
9 * Version: @(#)sock.h 1.0.4 05/13/93
10 *
11 * Authors: Ross Biro
12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13 * Corey Minyard <wf-rch!minyard@relay.EU.net>
14 * Florian La Roche <flla@stud.uni-sb.de>
15 *
16 * Fixes:
17 * Alan Cox : Volatiles in skbuff pointers. See
18 * skbuff comments. May be overdone,
19 * better to prove they can be removed
20 * than the reverse.
21 * Alan Cox : Added a zapped field for tcp to note
22 * a socket is reset and must stay shut up
23 * Alan Cox : New fields for options
24 * Pauline Middelink : identd support
25 * Alan Cox : Eliminate low level recv/recvfrom
26 * David S. Miller : New socket lookup architecture.
27 * Steve Whitehouse: Default routines for sock_ops
28 * Arnaldo C. Melo : removed net_pinfo, tp_pinfo and made
29 * protinfo be just a void pointer, as the
30 * protocol specific parts were moved to
31 * respective headers and ipv4/v6, etc now
32 * use private slabcaches for its socks
33 * Pedro Hortas : New flags field for socket options
34 */
35#ifndef _SOCK_H
36#define _SOCK_H
37
38#include <linux/hardirq.h>
39#include <linux/kernel.h>
40#include <linux/list.h>
41#include <linux/list_nulls.h>
42#include <linux/timer.h>
43#include <linux/cache.h>
44#include <linux/bitops.h>
45#include <linux/lockdep.h>
46#include <linux/netdevice.h>
47#include <linux/skbuff.h> /* struct sk_buff */
48#include <linux/mm.h>
49#include <linux/security.h>
50#include <linux/slab.h>
51#include <linux/uaccess.h>
52#include <linux/page_counter.h>
53#include <linux/memcontrol.h>
54#include <linux/static_key.h>
55#include <linux/sched.h>
56#include <linux/wait.h>
57#include <linux/cgroup-defs.h>
58#include <linux/rbtree.h>
59#include <linux/filter.h>
60#include <linux/rculist_nulls.h>
61#include <linux/poll.h>
62#include <linux/sockptr.h>
63#include <linux/indirect_call_wrapper.h>
64#include <linux/atomic.h>
65#include <linux/refcount.h>
66#include <net/dst.h>
67#include <net/checksum.h>
68#include <net/tcp_states.h>
69#include <linux/net_tstamp.h>
70#include <net/l3mdev.h>
71
72/*
73 * This structure really needs to be cleaned up.
74 * Most of it is for TCP, and not used by any of
75 * the other protocols.
76 */
77
78/* Define this to get the SOCK_DBG debugging facility. */
79#define SOCK_DEBUGGING
80#ifdef SOCK_DEBUGGING
81#define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
82 printk(KERN_DEBUG msg); } while (0)
83#else
84/* Validate arguments and do nothing */
85static inline __printf(2, 3)
86void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
87{
88}
89#endif
90
91/* This is the per-socket lock. The spinlock provides a synchronization
92 * between user contexts and software interrupt processing, whereas the
93 * mini-semaphore synchronizes multiple users amongst themselves.
94 */
95typedef struct {
96 spinlock_t slock;
97 int owned;
98 wait_queue_head_t wq;
99 /*
100 * We express the mutex-alike socket_lock semantics
101 * to the lock validator by explicitly managing
102 * the slock as a lock variant (in addition to
103 * the slock itself):
104 */
105#ifdef CONFIG_DEBUG_LOCK_ALLOC
106 struct lockdep_map dep_map;
107#endif
108} socket_lock_t;
109
110struct sock;
111struct proto;
112struct net;
113
114typedef __u32 __bitwise __portpair;
115typedef __u64 __bitwise __addrpair;
116
117/**
118 * struct sock_common - minimal network layer representation of sockets
119 * @skc_daddr: Foreign IPv4 addr
120 * @skc_rcv_saddr: Bound local IPv4 addr
121 * @skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
122 * @skc_hash: hash value used with various protocol lookup tables
123 * @skc_u16hashes: two u16 hash values used by UDP lookup tables
124 * @skc_dport: placeholder for inet_dport/tw_dport
125 * @skc_num: placeholder for inet_num/tw_num
126 * @skc_portpair: __u32 union of @skc_dport & @skc_num
127 * @skc_family: network address family
128 * @skc_state: Connection state
129 * @skc_reuse: %SO_REUSEADDR setting
130 * @skc_reuseport: %SO_REUSEPORT setting
131 * @skc_ipv6only: socket is IPV6 only
132 * @skc_net_refcnt: socket is using net ref counting
133 * @skc_bound_dev_if: bound device index if != 0
134 * @skc_bind_node: bind hash linkage for various protocol lookup tables
135 * @skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
136 * @skc_prot: protocol handlers inside a network family
137 * @skc_net: reference to the network namespace of this socket
138 * @skc_v6_daddr: IPV6 destination address
139 * @skc_v6_rcv_saddr: IPV6 source address
140 * @skc_cookie: socket's cookie value
141 * @skc_node: main hash linkage for various protocol lookup tables
142 * @skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
143 * @skc_tx_queue_mapping: tx queue number for this connection
144 * @skc_rx_queue_mapping: rx queue number for this connection
145 * @skc_flags: place holder for sk_flags
146 * %SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
147 * %SO_OOBINLINE settings, %SO_TIMESTAMPING settings
148 * @skc_listener: connection request listener socket (aka rsk_listener)
149 * [union with @skc_flags]
150 * @skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
151 * [union with @skc_flags]
152 * @skc_incoming_cpu: record/match cpu processing incoming packets
153 * @skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
154 * [union with @skc_incoming_cpu]
155 * @skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
156 * [union with @skc_incoming_cpu]
157 * @skc_refcnt: reference count
158 *
159 * This is the minimal network layer representation of sockets, the header
160 * for struct sock and struct inet_timewait_sock.
161 */
162struct sock_common {
163 /* skc_daddr and skc_rcv_saddr must be grouped on a 8 bytes aligned
164 * address on 64bit arches : cf INET_MATCH()
165 */
166 union {
167 __addrpair skc_addrpair;
168 struct {
169 __be32 skc_daddr;
170 __be32 skc_rcv_saddr;
171 };
172 };
173 union {
174 unsigned int skc_hash;
175 __u16 skc_u16hashes[2];
176 };
177 /* skc_dport && skc_num must be grouped as well */
178 union {
179 __portpair skc_portpair;
180 struct {
181 __be16 skc_dport;
182 __u16 skc_num;
183 };
184 };
185
186 unsigned short skc_family;
187 volatile unsigned char skc_state;
188 unsigned char skc_reuse:4;
189 unsigned char skc_reuseport:1;
190 unsigned char skc_ipv6only:1;
191 unsigned char skc_net_refcnt:1;
192 int skc_bound_dev_if;
193 union {
194 struct hlist_node skc_bind_node;
195 struct hlist_node skc_portaddr_node;
196 };
197 struct proto *skc_prot;
198 possible_net_t skc_net;
199
200#if IS_ENABLED(CONFIG_IPV6)
201 struct in6_addr skc_v6_daddr;
202 struct in6_addr skc_v6_rcv_saddr;
203#endif
204
205 atomic64_t skc_cookie;
206
207 /* following fields are padding to force
208 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
209 * assuming IPV6 is enabled. We use this padding differently
210 * for different kind of 'sockets'
211 */
212 union {
213 unsigned long skc_flags;
214 struct sock *skc_listener; /* request_sock */
215 struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
216 };
217 /*
218 * fields between dontcopy_begin/dontcopy_end
219 * are not copied in sock_copy()
220 */
221 /* private: */
222 int skc_dontcopy_begin[0];
223 /* public: */
224 union {
225 struct hlist_node skc_node;
226 struct hlist_nulls_node skc_nulls_node;
227 };
228 unsigned short skc_tx_queue_mapping;
229#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
230 unsigned short skc_rx_queue_mapping;
231#endif
232 union {
233 int skc_incoming_cpu;
234 u32 skc_rcv_wnd;
235 u32 skc_tw_rcv_nxt; /* struct tcp_timewait_sock */
236 };
237
238 refcount_t skc_refcnt;
239 /* private: */
240 int skc_dontcopy_end[0];
241 union {
242 u32 skc_rxhash;
243 u32 skc_window_clamp;
244 u32 skc_tw_snd_nxt; /* struct tcp_timewait_sock */
245 };
246 /* public: */
247};
248
249struct bpf_local_storage;
250
251/**
252 * struct sock - network layer representation of sockets
253 * @__sk_common: shared layout with inet_timewait_sock
254 * @sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
255 * @sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
256 * @sk_lock: synchronizer
257 * @sk_kern_sock: True if sock is using kernel lock classes
258 * @sk_rcvbuf: size of receive buffer in bytes
259 * @sk_wq: sock wait queue and async head
260 * @sk_rx_dst: receive input route used by early demux
261 * @sk_dst_cache: destination cache
262 * @sk_dst_pending_confirm: need to confirm neighbour
263 * @sk_policy: flow policy
264 * @sk_rx_skb_cache: cache copy of recently accessed RX skb
265 * @sk_receive_queue: incoming packets
266 * @sk_wmem_alloc: transmit queue bytes committed
267 * @sk_tsq_flags: TCP Small Queues flags
268 * @sk_write_queue: Packet sending queue
269 * @sk_omem_alloc: "o" is "option" or "other"
270 * @sk_wmem_queued: persistent queue size
271 * @sk_forward_alloc: space allocated forward
272 * @sk_napi_id: id of the last napi context to receive data for sk
273 * @sk_ll_usec: usecs to busypoll when there is no data
274 * @sk_allocation: allocation mode
275 * @sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
276 * @sk_pacing_status: Pacing status (requested, handled by sch_fq)
277 * @sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
278 * @sk_sndbuf: size of send buffer in bytes
279 * @__sk_flags_offset: empty field used to determine location of bitfield
280 * @sk_padding: unused element for alignment
281 * @sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
282 * @sk_no_check_rx: allow zero checksum in RX packets
283 * @sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
284 * @sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
285 * @sk_route_forced_caps: static, forced route capabilities
286 * (set in tcp_init_sock())
287 * @sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
288 * @sk_gso_max_size: Maximum GSO segment size to build
289 * @sk_gso_max_segs: Maximum number of GSO segments
290 * @sk_pacing_shift: scaling factor for TCP Small Queues
291 * @sk_lingertime: %SO_LINGER l_linger setting
292 * @sk_backlog: always used with the per-socket spinlock held
293 * @sk_callback_lock: used with the callbacks in the end of this struct
294 * @sk_error_queue: rarely used
295 * @sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
296 * IPV6_ADDRFORM for instance)
297 * @sk_err: last error
298 * @sk_err_soft: errors that don't cause failure but are the cause of a
299 * persistent failure not just 'timed out'
300 * @sk_drops: raw/udp drops counter
301 * @sk_ack_backlog: current listen backlog
302 * @sk_max_ack_backlog: listen backlog set in listen()
303 * @sk_uid: user id of owner
304 * @sk_prefer_busy_poll: prefer busypolling over softirq processing
305 * @sk_busy_poll_budget: napi processing budget when busypolling
306 * @sk_priority: %SO_PRIORITY setting
307 * @sk_type: socket type (%SOCK_STREAM, etc)
308 * @sk_protocol: which protocol this socket belongs in this network family
309 * @sk_peer_pid: &struct pid for this socket's peer
310 * @sk_peer_cred: %SO_PEERCRED setting
311 * @sk_rcvlowat: %SO_RCVLOWAT setting
312 * @sk_rcvtimeo: %SO_RCVTIMEO setting
313 * @sk_sndtimeo: %SO_SNDTIMEO setting
314 * @sk_txhash: computed flow hash for use on transmit
315 * @sk_filter: socket filtering instructions
316 * @sk_timer: sock cleanup timer
317 * @sk_stamp: time stamp of last packet received
318 * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
319 * @sk_tsflags: SO_TIMESTAMPING flags
320 * @sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
321 * for timestamping
322 * @sk_tskey: counter to disambiguate concurrent tstamp requests
323 * @sk_zckey: counter to order MSG_ZEROCOPY notifications
324 * @sk_socket: Identd and reporting IO signals
325 * @sk_user_data: RPC layer private data
326 * @sk_frag: cached page frag
327 * @sk_peek_off: current peek_offset value
328 * @sk_send_head: front of stuff to transmit
329 * @tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
330 * @sk_tx_skb_cache: cache copy of recently accessed TX skb
331 * @sk_security: used by security modules
332 * @sk_mark: generic packet mark
333 * @sk_cgrp_data: cgroup data for this cgroup
334 * @sk_memcg: this socket's memory cgroup association
335 * @sk_write_pending: a write to stream socket waits to start
336 * @sk_state_change: callback to indicate change in the state of the sock
337 * @sk_data_ready: callback to indicate there is data to be processed
338 * @sk_write_space: callback to indicate there is bf sending space available
339 * @sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
340 * @sk_backlog_rcv: callback to process the backlog
341 * @sk_validate_xmit_skb: ptr to an optional validate function
342 * @sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
343 * @sk_reuseport_cb: reuseport group container
344 * @sk_bpf_storage: ptr to cache and control for bpf_sk_storage
345 * @sk_rcu: used during RCU grace period
346 * @sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
347 * @sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
348 * @sk_txtime_report_errors: set report errors mode for SO_TXTIME
349 * @sk_txtime_unused: unused txtime flags
350 */
351struct sock {
352 /*
353 * Now struct inet_timewait_sock also uses sock_common, so please just
354 * don't add nothing before this first member (__sk_common) --acme
355 */
356 struct sock_common __sk_common;
357#define sk_node __sk_common.skc_node
358#define sk_nulls_node __sk_common.skc_nulls_node
359#define sk_refcnt __sk_common.skc_refcnt
360#define sk_tx_queue_mapping __sk_common.skc_tx_queue_mapping
361#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
362#define sk_rx_queue_mapping __sk_common.skc_rx_queue_mapping
363#endif
364
365#define sk_dontcopy_begin __sk_common.skc_dontcopy_begin
366#define sk_dontcopy_end __sk_common.skc_dontcopy_end
367#define sk_hash __sk_common.skc_hash
368#define sk_portpair __sk_common.skc_portpair
369#define sk_num __sk_common.skc_num
370#define sk_dport __sk_common.skc_dport
371#define sk_addrpair __sk_common.skc_addrpair
372#define sk_daddr __sk_common.skc_daddr
373#define sk_rcv_saddr __sk_common.skc_rcv_saddr
374#define sk_family __sk_common.skc_family
375#define sk_state __sk_common.skc_state
376#define sk_reuse __sk_common.skc_reuse
377#define sk_reuseport __sk_common.skc_reuseport
378#define sk_ipv6only __sk_common.skc_ipv6only
379#define sk_net_refcnt __sk_common.skc_net_refcnt
380#define sk_bound_dev_if __sk_common.skc_bound_dev_if
381#define sk_bind_node __sk_common.skc_bind_node
382#define sk_prot __sk_common.skc_prot
383#define sk_net __sk_common.skc_net
384#define sk_v6_daddr __sk_common.skc_v6_daddr
385#define sk_v6_rcv_saddr __sk_common.skc_v6_rcv_saddr
386#define sk_cookie __sk_common.skc_cookie
387#define sk_incoming_cpu __sk_common.skc_incoming_cpu
388#define sk_flags __sk_common.skc_flags
389#define sk_rxhash __sk_common.skc_rxhash
390
391 socket_lock_t sk_lock;
392 atomic_t sk_drops;
393 int sk_rcvlowat;
394 struct sk_buff_head sk_error_queue;
395 struct sk_buff *sk_rx_skb_cache;
396 struct sk_buff_head sk_receive_queue;
397 /*
398 * The backlog queue is special, it is always used with
399 * the per-socket spinlock held and requires low latency
400 * access. Therefore we special case it's implementation.
401 * Note : rmem_alloc is in this structure to fill a hole
402 * on 64bit arches, not because its logically part of
403 * backlog.
404 */
405 struct {
406 atomic_t rmem_alloc;
407 int len;
408 struct sk_buff *head;
409 struct sk_buff *tail;
410 } sk_backlog;
411#define sk_rmem_alloc sk_backlog.rmem_alloc
412
413 int sk_forward_alloc;
414#ifdef CONFIG_NET_RX_BUSY_POLL
415 unsigned int sk_ll_usec;
416 /* ===== mostly read cache line ===== */
417 unsigned int sk_napi_id;
418#endif
419 int sk_rcvbuf;
420
421 struct sk_filter __rcu *sk_filter;
422 union {
423 struct socket_wq __rcu *sk_wq;
424 /* private: */
425 struct socket_wq *sk_wq_raw;
426 /* public: */
427 };
428#ifdef CONFIG_XFRM
429 struct xfrm_policy __rcu *sk_policy[2];
430#endif
431 struct dst_entry *sk_rx_dst;
432 struct dst_entry __rcu *sk_dst_cache;
433 atomic_t sk_omem_alloc;
434 int sk_sndbuf;
435
436 /* ===== cache line for TX ===== */
437 int sk_wmem_queued;
438 refcount_t sk_wmem_alloc;
439 unsigned long sk_tsq_flags;
440 union {
441 struct sk_buff *sk_send_head;
442 struct rb_root tcp_rtx_queue;
443 };
444 struct sk_buff *sk_tx_skb_cache;
445 struct sk_buff_head sk_write_queue;
446 __s32 sk_peek_off;
447 int sk_write_pending;
448 __u32 sk_dst_pending_confirm;
449 u32 sk_pacing_status; /* see enum sk_pacing */
450 long sk_sndtimeo;
451 struct timer_list sk_timer;
452 __u32 sk_priority;
453 __u32 sk_mark;
454 unsigned long sk_pacing_rate; /* bytes per second */
455 unsigned long sk_max_pacing_rate;
456 struct page_frag sk_frag;
457 netdev_features_t sk_route_caps;
458 netdev_features_t sk_route_nocaps;
459 netdev_features_t sk_route_forced_caps;
460 int sk_gso_type;
461 unsigned int sk_gso_max_size;
462 gfp_t sk_allocation;
463 __u32 sk_txhash;
464
465 /*
466 * Because of non atomicity rules, all
467 * changes are protected by socket lock.
468 */
469 u8 sk_padding : 1,
470 sk_kern_sock : 1,
471 sk_no_check_tx : 1,
472 sk_no_check_rx : 1,
473 sk_userlocks : 4;
474 u8 sk_pacing_shift;
475 u16 sk_type;
476 u16 sk_protocol;
477 u16 sk_gso_max_segs;
478 unsigned long sk_lingertime;
479 struct proto *sk_prot_creator;
480 rwlock_t sk_callback_lock;
481 int sk_err,
482 sk_err_soft;
483 u32 sk_ack_backlog;
484 u32 sk_max_ack_backlog;
485 kuid_t sk_uid;
486#ifdef CONFIG_NET_RX_BUSY_POLL
487 u8 sk_prefer_busy_poll;
488 u16 sk_busy_poll_budget;
489#endif
490 spinlock_t sk_peer_lock;
491 struct pid *sk_peer_pid;
492 const struct cred *sk_peer_cred;
493
494 long sk_rcvtimeo;
495 ktime_t sk_stamp;
496#if BITS_PER_LONG==32
497 seqlock_t sk_stamp_seq;
498#endif
499 u16 sk_tsflags;
500 int sk_bind_phc;
501 u8 sk_shutdown;
502 u32 sk_tskey;
503 atomic_t sk_zckey;
504
505 u8 sk_clockid;
506 u8 sk_txtime_deadline_mode : 1,
507 sk_txtime_report_errors : 1,
508 sk_txtime_unused : 6;
509
510 struct socket *sk_socket;
511 void *sk_user_data;
512#ifdef CONFIG_SECURITY
513 void *sk_security;
514#endif
515 struct sock_cgroup_data sk_cgrp_data;
516 struct mem_cgroup *sk_memcg;
517 void (*sk_state_change)(struct sock *sk);
518 void (*sk_data_ready)(struct sock *sk);
519 void (*sk_write_space)(struct sock *sk);
520 void (*sk_error_report)(struct sock *sk);
521 int (*sk_backlog_rcv)(struct sock *sk,
522 struct sk_buff *skb);
523#ifdef CONFIG_SOCK_VALIDATE_XMIT
524 struct sk_buff* (*sk_validate_xmit_skb)(struct sock *sk,
525 struct net_device *dev,
526 struct sk_buff *skb);
527#endif
528 void (*sk_destruct)(struct sock *sk);
529 struct sock_reuseport __rcu *sk_reuseport_cb;
530#ifdef CONFIG_BPF_SYSCALL
531 struct bpf_local_storage __rcu *sk_bpf_storage;
532#endif
533 struct rcu_head sk_rcu;
534};
535
536enum sk_pacing {
537 SK_PACING_NONE = 0,
538 SK_PACING_NEEDED = 1,
539 SK_PACING_FQ = 2,
540};
541
542/* Pointer stored in sk_user_data might not be suitable for copying
543 * when cloning the socket. For instance, it can point to a reference
544 * counted object. sk_user_data bottom bit is set if pointer must not
545 * be copied.
546 */
547#define SK_USER_DATA_NOCOPY 1UL
548#define SK_USER_DATA_BPF 2UL /* Managed by BPF */
549#define SK_USER_DATA_PTRMASK ~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF)
550
551/**
552 * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
553 * @sk: socket
554 */
555static inline bool sk_user_data_is_nocopy(const struct sock *sk)
556{
557 return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
558}
559
560#define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
561
562#define rcu_dereference_sk_user_data(sk) \
563({ \
564 void *__tmp = rcu_dereference(__sk_user_data((sk))); \
565 (void *)((uintptr_t)__tmp & SK_USER_DATA_PTRMASK); \
566})
567#define rcu_assign_sk_user_data(sk, ptr) \
568({ \
569 uintptr_t __tmp = (uintptr_t)(ptr); \
570 WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \
571 rcu_assign_pointer(__sk_user_data((sk)), __tmp); \
572})
573#define rcu_assign_sk_user_data_nocopy(sk, ptr) \
574({ \
575 uintptr_t __tmp = (uintptr_t)(ptr); \
576 WARN_ON_ONCE(__tmp & ~SK_USER_DATA_PTRMASK); \
577 rcu_assign_pointer(__sk_user_data((sk)), \
578 __tmp | SK_USER_DATA_NOCOPY); \
579})
580
581/*
582 * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
583 * or not whether his port will be reused by someone else. SK_FORCE_REUSE
584 * on a socket means that the socket will reuse everybody else's port
585 * without looking at the other's sk_reuse value.
586 */
587
588#define SK_NO_REUSE 0
589#define SK_CAN_REUSE 1
590#define SK_FORCE_REUSE 2
591
592int sk_set_peek_off(struct sock *sk, int val);
593
594static inline int sk_peek_offset(struct sock *sk, int flags)
595{
596 if (unlikely(flags & MSG_PEEK)) {
597 return READ_ONCE(sk->sk_peek_off);
598 }
599
600 return 0;
601}
602
603static inline void sk_peek_offset_bwd(struct sock *sk, int val)
604{
605 s32 off = READ_ONCE(sk->sk_peek_off);
606
607 if (unlikely(off >= 0)) {
608 off = max_t(s32, off - val, 0);
609 WRITE_ONCE(sk->sk_peek_off, off);
610 }
611}
612
613static inline void sk_peek_offset_fwd(struct sock *sk, int val)
614{
615 sk_peek_offset_bwd(sk, -val);
616}
617
618/*
619 * Hashed lists helper routines
620 */
621static inline struct sock *sk_entry(const struct hlist_node *node)
622{
623 return hlist_entry(node, struct sock, sk_node);
624}
625
626static inline struct sock *__sk_head(const struct hlist_head *head)
627{
628 return hlist_entry(head->first, struct sock, sk_node);
629}
630
631static inline struct sock *sk_head(const struct hlist_head *head)
632{
633 return hlist_empty(head) ? NULL : __sk_head(head);
634}
635
636static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
637{
638 return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
639}
640
641static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
642{
643 return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
644}
645
646static inline struct sock *sk_next(const struct sock *sk)
647{
648 return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
649}
650
651static inline struct sock *sk_nulls_next(const struct sock *sk)
652{
653 return (!is_a_nulls(sk->sk_nulls_node.next)) ?
654 hlist_nulls_entry(sk->sk_nulls_node.next,
655 struct sock, sk_nulls_node) :
656 NULL;
657}
658
659static inline bool sk_unhashed(const struct sock *sk)
660{
661 return hlist_unhashed(&sk->sk_node);
662}
663
664static inline bool sk_hashed(const struct sock *sk)
665{
666 return !sk_unhashed(sk);
667}
668
669static inline void sk_node_init(struct hlist_node *node)
670{
671 node->pprev = NULL;
672}
673
674static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
675{
676 node->pprev = NULL;
677}
678
679static inline void __sk_del_node(struct sock *sk)
680{
681 __hlist_del(&sk->sk_node);
682}
683
684/* NB: equivalent to hlist_del_init_rcu */
685static inline bool __sk_del_node_init(struct sock *sk)
686{
687 if (sk_hashed(sk)) {
688 __sk_del_node(sk);
689 sk_node_init(&sk->sk_node);
690 return true;
691 }
692 return false;
693}
694
695/* Grab socket reference count. This operation is valid only
696 when sk is ALREADY grabbed f.e. it is found in hash table
697 or a list and the lookup is made under lock preventing hash table
698 modifications.
699 */
700
701static __always_inline void sock_hold(struct sock *sk)
702{
703 refcount_inc(&sk->sk_refcnt);
704}
705
706/* Ungrab socket in the context, which assumes that socket refcnt
707 cannot hit zero, f.e. it is true in context of any socketcall.
708 */
709static __always_inline void __sock_put(struct sock *sk)
710{
711 refcount_dec(&sk->sk_refcnt);
712}
713
714static inline bool sk_del_node_init(struct sock *sk)
715{
716 bool rc = __sk_del_node_init(sk);
717
718 if (rc) {
719 /* paranoid for a while -acme */
720 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
721 __sock_put(sk);
722 }
723 return rc;
724}
725#define sk_del_node_init_rcu(sk) sk_del_node_init(sk)
726
727static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
728{
729 if (sk_hashed(sk)) {
730 hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
731 return true;
732 }
733 return false;
734}
735
736static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
737{
738 bool rc = __sk_nulls_del_node_init_rcu(sk);
739
740 if (rc) {
741 /* paranoid for a while -acme */
742 WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
743 __sock_put(sk);
744 }
745 return rc;
746}
747
748static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
749{
750 hlist_add_head(&sk->sk_node, list);
751}
752
753static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
754{
755 sock_hold(sk);
756 __sk_add_node(sk, list);
757}
758
759static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
760{
761 sock_hold(sk);
762 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
763 sk->sk_family == AF_INET6)
764 hlist_add_tail_rcu(&sk->sk_node, list);
765 else
766 hlist_add_head_rcu(&sk->sk_node, list);
767}
768
769static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
770{
771 sock_hold(sk);
772 hlist_add_tail_rcu(&sk->sk_node, list);
773}
774
775static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
776{
777 hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
778}
779
780static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
781{
782 hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
783}
784
785static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
786{
787 sock_hold(sk);
788 __sk_nulls_add_node_rcu(sk, list);
789}
790
791static inline void __sk_del_bind_node(struct sock *sk)
792{
793 __hlist_del(&sk->sk_bind_node);
794}
795
796static inline void sk_add_bind_node(struct sock *sk,
797 struct hlist_head *list)
798{
799 hlist_add_head(&sk->sk_bind_node, list);
800}
801
802#define sk_for_each(__sk, list) \
803 hlist_for_each_entry(__sk, list, sk_node)
804#define sk_for_each_rcu(__sk, list) \
805 hlist_for_each_entry_rcu(__sk, list, sk_node)
806#define sk_nulls_for_each(__sk, node, list) \
807 hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
808#define sk_nulls_for_each_rcu(__sk, node, list) \
809 hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
810#define sk_for_each_from(__sk) \
811 hlist_for_each_entry_from(__sk, sk_node)
812#define sk_nulls_for_each_from(__sk, node) \
813 if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
814 hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
815#define sk_for_each_safe(__sk, tmp, list) \
816 hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
817#define sk_for_each_bound(__sk, list) \
818 hlist_for_each_entry(__sk, list, sk_bind_node)
819
820/**
821 * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
822 * @tpos: the type * to use as a loop cursor.
823 * @pos: the &struct hlist_node to use as a loop cursor.
824 * @head: the head for your list.
825 * @offset: offset of hlist_node within the struct.
826 *
827 */
828#define sk_for_each_entry_offset_rcu(tpos, pos, head, offset) \
829 for (pos = rcu_dereference(hlist_first_rcu(head)); \
830 pos != NULL && \
831 ({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;}); \
832 pos = rcu_dereference(hlist_next_rcu(pos)))
833
834static inline struct user_namespace *sk_user_ns(struct sock *sk)
835{
836 /* Careful only use this in a context where these parameters
837 * can not change and must all be valid, such as recvmsg from
838 * userspace.
839 */
840 return sk->sk_socket->file->f_cred->user_ns;
841}
842
843/* Sock flags */
844enum sock_flags {
845 SOCK_DEAD,
846 SOCK_DONE,
847 SOCK_URGINLINE,
848 SOCK_KEEPOPEN,
849 SOCK_LINGER,
850 SOCK_DESTROY,
851 SOCK_BROADCAST,
852 SOCK_TIMESTAMP,
853 SOCK_ZAPPED,
854 SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
855 SOCK_DBG, /* %SO_DEBUG setting */
856 SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
857 SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
858 SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
859 SOCK_MEMALLOC, /* VM depends on this socket for swapping */
860 SOCK_TIMESTAMPING_RX_SOFTWARE, /* %SOF_TIMESTAMPING_RX_SOFTWARE */
861 SOCK_FASYNC, /* fasync() active */
862 SOCK_RXQ_OVFL,
863 SOCK_ZEROCOPY, /* buffers from userspace */
864 SOCK_WIFI_STATUS, /* push wifi status to userspace */
865 SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
866 * Will use last 4 bytes of packet sent from
867 * user-space instead.
868 */
869 SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
870 SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
871 SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
872 SOCK_TXTIME,
873 SOCK_XDP, /* XDP is attached */
874 SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
875};
876
877#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
878
879static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
880{
881 nsk->sk_flags = osk->sk_flags;
882}
883
884static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
885{
886 __set_bit(flag, &sk->sk_flags);
887}
888
889static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
890{
891 __clear_bit(flag, &sk->sk_flags);
892}
893
894static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
895 int valbool)
896{
897 if (valbool)
898 sock_set_flag(sk, bit);
899 else
900 sock_reset_flag(sk, bit);
901}
902
903static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
904{
905 return test_bit(flag, &sk->sk_flags);
906}
907
908#ifdef CONFIG_NET
909DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
910static inline int sk_memalloc_socks(void)
911{
912 return static_branch_unlikely(&memalloc_socks_key);
913}
914
915void __receive_sock(struct file *file);
916#else
917
918static inline int sk_memalloc_socks(void)
919{
920 return 0;
921}
922
923static inline void __receive_sock(struct file *file)
924{ }
925#endif
926
927static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
928{
929 return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
930}
931
932static inline void sk_acceptq_removed(struct sock *sk)
933{
934 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
935}
936
937static inline void sk_acceptq_added(struct sock *sk)
938{
939 WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
940}
941
942/* Note: If you think the test should be:
943 * return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
944 * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
945 */
946static inline bool sk_acceptq_is_full(const struct sock *sk)
947{
948 return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
949}
950
951/*
952 * Compute minimal free write space needed to queue new packets.
953 */
954static inline int sk_stream_min_wspace(const struct sock *sk)
955{
956 return READ_ONCE(sk->sk_wmem_queued) >> 1;
957}
958
959static inline int sk_stream_wspace(const struct sock *sk)
960{
961 return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
962}
963
964static inline void sk_wmem_queued_add(struct sock *sk, int val)
965{
966 WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
967}
968
969void sk_stream_write_space(struct sock *sk);
970
971/* OOB backlog add */
972static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
973{
974 /* dont let skb dst not refcounted, we are going to leave rcu lock */
975 skb_dst_force(skb);
976
977 if (!sk->sk_backlog.tail)
978 WRITE_ONCE(sk->sk_backlog.head, skb);
979 else
980 sk->sk_backlog.tail->next = skb;
981
982 WRITE_ONCE(sk->sk_backlog.tail, skb);
983 skb->next = NULL;
984}
985
986/*
987 * Take into account size of receive queue and backlog queue
988 * Do not take into account this skb truesize,
989 * to allow even a single big packet to come.
990 */
991static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
992{
993 unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
994
995 return qsize > limit;
996}
997
998/* The per-socket spinlock must be held here. */
999static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1000 unsigned int limit)
1001{
1002 if (sk_rcvqueues_full(sk, limit))
1003 return -ENOBUFS;
1004
1005 /*
1006 * If the skb was allocated from pfmemalloc reserves, only
1007 * allow SOCK_MEMALLOC sockets to use it as this socket is
1008 * helping free memory
1009 */
1010 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1011 return -ENOMEM;
1012
1013 __sk_add_backlog(sk, skb);
1014 sk->sk_backlog.len += skb->truesize;
1015 return 0;
1016}
1017
1018int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1019
1020static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1021{
1022 if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1023 return __sk_backlog_rcv(sk, skb);
1024
1025 return sk->sk_backlog_rcv(sk, skb);
1026}
1027
1028static inline void sk_incoming_cpu_update(struct sock *sk)
1029{
1030 int cpu = raw_smp_processor_id();
1031
1032 if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1033 WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1034}
1035
1036static inline void sock_rps_record_flow_hash(__u32 hash)
1037{
1038#ifdef CONFIG_RPS
1039 struct rps_sock_flow_table *sock_flow_table;
1040
1041 rcu_read_lock();
1042 sock_flow_table = rcu_dereference(rps_sock_flow_table);
1043 rps_record_sock_flow(sock_flow_table, hash);
1044 rcu_read_unlock();
1045#endif
1046}
1047
1048static inline void sock_rps_record_flow(const struct sock *sk)
1049{
1050#ifdef CONFIG_RPS
1051 if (static_branch_unlikely(&rfs_needed)) {
1052 /* Reading sk->sk_rxhash might incur an expensive cache line
1053 * miss.
1054 *
1055 * TCP_ESTABLISHED does cover almost all states where RFS
1056 * might be useful, and is cheaper [1] than testing :
1057 * IPv4: inet_sk(sk)->inet_daddr
1058 * IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
1059 * OR an additional socket flag
1060 * [1] : sk_state and sk_prot are in the same cache line.
1061 */
1062 if (sk->sk_state == TCP_ESTABLISHED)
1063 sock_rps_record_flow_hash(sk->sk_rxhash);
1064 }
1065#endif
1066}
1067
1068static inline void sock_rps_save_rxhash(struct sock *sk,
1069 const struct sk_buff *skb)
1070{
1071#ifdef CONFIG_RPS
1072 if (unlikely(sk->sk_rxhash != skb->hash))
1073 sk->sk_rxhash = skb->hash;
1074#endif
1075}
1076
1077static inline void sock_rps_reset_rxhash(struct sock *sk)
1078{
1079#ifdef CONFIG_RPS
1080 sk->sk_rxhash = 0;
1081#endif
1082}
1083
1084#define sk_wait_event(__sk, __timeo, __condition, __wait) \
1085 ({ int __rc; \
1086 release_sock(__sk); \
1087 __rc = __condition; \
1088 if (!__rc) { \
1089 *(__timeo) = wait_woken(__wait, \
1090 TASK_INTERRUPTIBLE, \
1091 *(__timeo)); \
1092 } \
1093 sched_annotate_sleep(); \
1094 lock_sock(__sk); \
1095 __rc = __condition; \
1096 __rc; \
1097 })
1098
1099int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1100int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1101void sk_stream_wait_close(struct sock *sk, long timeo_p);
1102int sk_stream_error(struct sock *sk, int flags, int err);
1103void sk_stream_kill_queues(struct sock *sk);
1104void sk_set_memalloc(struct sock *sk);
1105void sk_clear_memalloc(struct sock *sk);
1106
1107void __sk_flush_backlog(struct sock *sk);
1108
1109static inline bool sk_flush_backlog(struct sock *sk)
1110{
1111 if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1112 __sk_flush_backlog(sk);
1113 return true;
1114 }
1115 return false;
1116}
1117
1118int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1119
1120struct request_sock_ops;
1121struct timewait_sock_ops;
1122struct inet_hashinfo;
1123struct raw_hashinfo;
1124struct smc_hashinfo;
1125struct module;
1126struct sk_psock;
1127
1128/*
1129 * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1130 * un-modified. Special care is taken when initializing object to zero.
1131 */
1132static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1133{
1134 if (offsetof(struct sock, sk_node.next) != 0)
1135 memset(sk, 0, offsetof(struct sock, sk_node.next));
1136 memset(&sk->sk_node.pprev, 0,
1137 size - offsetof(struct sock, sk_node.pprev));
1138}
1139
1140/* Networking protocol blocks we attach to sockets.
1141 * socket layer -> transport layer interface
1142 */
1143struct proto {
1144 void (*close)(struct sock *sk,
1145 long timeout);
1146 int (*pre_connect)(struct sock *sk,
1147 struct sockaddr *uaddr,
1148 int addr_len);
1149 int (*connect)(struct sock *sk,
1150 struct sockaddr *uaddr,
1151 int addr_len);
1152 int (*disconnect)(struct sock *sk, int flags);
1153
1154 struct sock * (*accept)(struct sock *sk, int flags, int *err,
1155 bool kern);
1156
1157 int (*ioctl)(struct sock *sk, int cmd,
1158 unsigned long arg);
1159 int (*init)(struct sock *sk);
1160 void (*destroy)(struct sock *sk);
1161 void (*shutdown)(struct sock *sk, int how);
1162 int (*setsockopt)(struct sock *sk, int level,
1163 int optname, sockptr_t optval,
1164 unsigned int optlen);
1165 int (*getsockopt)(struct sock *sk, int level,
1166 int optname, char __user *optval,
1167 int __user *option);
1168 void (*keepalive)(struct sock *sk, int valbool);
1169#ifdef CONFIG_COMPAT
1170 int (*compat_ioctl)(struct sock *sk,
1171 unsigned int cmd, unsigned long arg);
1172#endif
1173 int (*sendmsg)(struct sock *sk, struct msghdr *msg,
1174 size_t len);
1175 int (*recvmsg)(struct sock *sk, struct msghdr *msg,
1176 size_t len, int noblock, int flags,
1177 int *addr_len);
1178 int (*sendpage)(struct sock *sk, struct page *page,
1179 int offset, size_t size, int flags);
1180 int (*bind)(struct sock *sk,
1181 struct sockaddr *addr, int addr_len);
1182 int (*bind_add)(struct sock *sk,
1183 struct sockaddr *addr, int addr_len);
1184
1185 int (*backlog_rcv) (struct sock *sk,
1186 struct sk_buff *skb);
1187 bool (*bpf_bypass_getsockopt)(int level,
1188 int optname);
1189
1190 void (*release_cb)(struct sock *sk);
1191
1192 /* Keeping track of sk's, looking them up, and port selection methods. */
1193 int (*hash)(struct sock *sk);
1194 void (*unhash)(struct sock *sk);
1195 void (*rehash)(struct sock *sk);
1196 int (*get_port)(struct sock *sk, unsigned short snum);
1197#ifdef CONFIG_BPF_SYSCALL
1198 int (*psock_update_sk_prot)(struct sock *sk,
1199 struct sk_psock *psock,
1200 bool restore);
1201#endif
1202
1203 /* Keeping track of sockets in use */
1204#ifdef CONFIG_PROC_FS
1205 unsigned int inuse_idx;
1206#endif
1207
1208 bool (*stream_memory_free)(const struct sock *sk, int wake);
1209 bool (*stream_memory_read)(const struct sock *sk);
1210 /* Memory pressure */
1211 void (*enter_memory_pressure)(struct sock *sk);
1212 void (*leave_memory_pressure)(struct sock *sk);
1213 atomic_long_t *memory_allocated; /* Current allocated memory. */
1214 struct percpu_counter *sockets_allocated; /* Current number of sockets. */
1215 /*
1216 * Pressure flag: try to collapse.
1217 * Technical note: it is used by multiple contexts non atomically.
1218 * All the __sk_mem_schedule() is of this nature: accounting
1219 * is strict, actions are advisory and have some latency.
1220 */
1221 unsigned long *memory_pressure;
1222 long *sysctl_mem;
1223
1224 int *sysctl_wmem;
1225 int *sysctl_rmem;
1226 u32 sysctl_wmem_offset;
1227 u32 sysctl_rmem_offset;
1228
1229 int max_header;
1230 bool no_autobind;
1231
1232 struct kmem_cache *slab;
1233 unsigned int obj_size;
1234 slab_flags_t slab_flags;
1235 unsigned int useroffset; /* Usercopy region offset */
1236 unsigned int usersize; /* Usercopy region size */
1237
1238 struct percpu_counter *orphan_count;
1239
1240 struct request_sock_ops *rsk_prot;
1241 struct timewait_sock_ops *twsk_prot;
1242
1243 union {
1244 struct inet_hashinfo *hashinfo;
1245 struct udp_table *udp_table;
1246 struct raw_hashinfo *raw_hash;
1247 struct smc_hashinfo *smc_hash;
1248 } h;
1249
1250 struct module *owner;
1251
1252 char name[32];
1253
1254 struct list_head node;
1255#ifdef SOCK_REFCNT_DEBUG
1256 atomic_t socks;
1257#endif
1258 int (*diag_destroy)(struct sock *sk, int err);
1259} __randomize_layout;
1260
1261int proto_register(struct proto *prot, int alloc_slab);
1262void proto_unregister(struct proto *prot);
1263int sock_load_diag_module(int family, int protocol);
1264
1265#ifdef SOCK_REFCNT_DEBUG
1266static inline void sk_refcnt_debug_inc(struct sock *sk)
1267{
1268 atomic_inc(&sk->sk_prot->socks);
1269}
1270
1271static inline void sk_refcnt_debug_dec(struct sock *sk)
1272{
1273 atomic_dec(&sk->sk_prot->socks);
1274 printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1275 sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1276}
1277
1278static inline void sk_refcnt_debug_release(const struct sock *sk)
1279{
1280 if (refcount_read(&sk->sk_refcnt) != 1)
1281 printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1282 sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1283}
1284#else /* SOCK_REFCNT_DEBUG */
1285#define sk_refcnt_debug_inc(sk) do { } while (0)
1286#define sk_refcnt_debug_dec(sk) do { } while (0)
1287#define sk_refcnt_debug_release(sk) do { } while (0)
1288#endif /* SOCK_REFCNT_DEBUG */
1289
1290INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1291
1292static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1293{
1294 if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1295 return false;
1296
1297#ifdef CONFIG_INET
1298 return sk->sk_prot->stream_memory_free ?
1299 INDIRECT_CALL_1(sk->sk_prot->stream_memory_free,
1300 tcp_stream_memory_free,
1301 sk, wake) : true;
1302#else
1303 return sk->sk_prot->stream_memory_free ?
1304 sk->sk_prot->stream_memory_free(sk, wake) : true;
1305#endif
1306}
1307
1308static inline bool sk_stream_memory_free(const struct sock *sk)
1309{
1310 return __sk_stream_memory_free(sk, 0);
1311}
1312
1313static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1314{
1315 return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1316 __sk_stream_memory_free(sk, wake);
1317}
1318
1319static inline bool sk_stream_is_writeable(const struct sock *sk)
1320{
1321 return __sk_stream_is_writeable(sk, 0);
1322}
1323
1324static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1325 struct cgroup *ancestor)
1326{
1327#ifdef CONFIG_SOCK_CGROUP_DATA
1328 return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1329 ancestor);
1330#else
1331 return -ENOTSUPP;
1332#endif
1333}
1334
1335static inline bool sk_has_memory_pressure(const struct sock *sk)
1336{
1337 return sk->sk_prot->memory_pressure != NULL;
1338}
1339
1340static inline bool sk_under_memory_pressure(const struct sock *sk)
1341{
1342 if (!sk->sk_prot->memory_pressure)
1343 return false;
1344
1345 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1346 mem_cgroup_under_socket_pressure(sk->sk_memcg))
1347 return true;
1348
1349 return !!*sk->sk_prot->memory_pressure;
1350}
1351
1352static inline long
1353sk_memory_allocated(const struct sock *sk)
1354{
1355 return atomic_long_read(sk->sk_prot->memory_allocated);
1356}
1357
1358static inline long
1359sk_memory_allocated_add(struct sock *sk, int amt)
1360{
1361 return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1362}
1363
1364static inline void
1365sk_memory_allocated_sub(struct sock *sk, int amt)
1366{
1367 atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1368}
1369
1370#define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1371
1372static inline void sk_sockets_allocated_dec(struct sock *sk)
1373{
1374 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1375 SK_ALLOC_PERCPU_COUNTER_BATCH);
1376}
1377
1378static inline void sk_sockets_allocated_inc(struct sock *sk)
1379{
1380 percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1381 SK_ALLOC_PERCPU_COUNTER_BATCH);
1382}
1383
1384static inline u64
1385sk_sockets_allocated_read_positive(struct sock *sk)
1386{
1387 return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1388}
1389
1390static inline int
1391proto_sockets_allocated_sum_positive(struct proto *prot)
1392{
1393 return percpu_counter_sum_positive(prot->sockets_allocated);
1394}
1395
1396static inline long
1397proto_memory_allocated(struct proto *prot)
1398{
1399 return atomic_long_read(prot->memory_allocated);
1400}
1401
1402static inline bool
1403proto_memory_pressure(struct proto *prot)
1404{
1405 if (!prot->memory_pressure)
1406 return false;
1407 return !!*prot->memory_pressure;
1408}
1409
1410
1411#ifdef CONFIG_PROC_FS
1412/* Called with local bh disabled */
1413void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1414int sock_prot_inuse_get(struct net *net, struct proto *proto);
1415int sock_inuse_get(struct net *net);
1416#else
1417static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1418 int inc)
1419{
1420}
1421#endif
1422
1423
1424/* With per-bucket locks this operation is not-atomic, so that
1425 * this version is not worse.
1426 */
1427static inline int __sk_prot_rehash(struct sock *sk)
1428{
1429 sk->sk_prot->unhash(sk);
1430 return sk->sk_prot->hash(sk);
1431}
1432
1433/* About 10 seconds */
1434#define SOCK_DESTROY_TIME (10*HZ)
1435
1436/* Sockets 0-1023 can't be bound to unless you are superuser */
1437#define PROT_SOCK 1024
1438
1439#define SHUTDOWN_MASK 3
1440#define RCV_SHUTDOWN 1
1441#define SEND_SHUTDOWN 2
1442
1443#define SOCK_SNDBUF_LOCK 1
1444#define SOCK_RCVBUF_LOCK 2
1445#define SOCK_BINDADDR_LOCK 4
1446#define SOCK_BINDPORT_LOCK 8
1447
1448struct socket_alloc {
1449 struct socket socket;
1450 struct inode vfs_inode;
1451};
1452
1453static inline struct socket *SOCKET_I(struct inode *inode)
1454{
1455 return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1456}
1457
1458static inline struct inode *SOCK_INODE(struct socket *socket)
1459{
1460 return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1461}
1462
1463/*
1464 * Functions for memory accounting
1465 */
1466int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1467int __sk_mem_schedule(struct sock *sk, int size, int kind);
1468void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1469void __sk_mem_reclaim(struct sock *sk, int amount);
1470
1471/* We used to have PAGE_SIZE here, but systems with 64KB pages
1472 * do not necessarily have 16x time more memory than 4KB ones.
1473 */
1474#define SK_MEM_QUANTUM 4096
1475#define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1476#define SK_MEM_SEND 0
1477#define SK_MEM_RECV 1
1478
1479/* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
1480static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1481{
1482 long val = sk->sk_prot->sysctl_mem[index];
1483
1484#if PAGE_SIZE > SK_MEM_QUANTUM
1485 val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1486#elif PAGE_SIZE < SK_MEM_QUANTUM
1487 val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1488#endif
1489 return val;
1490}
1491
1492static inline int sk_mem_pages(int amt)
1493{
1494 return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1495}
1496
1497static inline bool sk_has_account(struct sock *sk)
1498{
1499 /* return true if protocol supports memory accounting */
1500 return !!sk->sk_prot->memory_allocated;
1501}
1502
1503static inline bool sk_wmem_schedule(struct sock *sk, int size)
1504{
1505 if (!sk_has_account(sk))
1506 return true;
1507 return size <= sk->sk_forward_alloc ||
1508 __sk_mem_schedule(sk, size, SK_MEM_SEND);
1509}
1510
1511static inline bool
1512sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1513{
1514 if (!sk_has_account(sk))
1515 return true;
1516 return size <= sk->sk_forward_alloc ||
1517 __sk_mem_schedule(sk, size, SK_MEM_RECV) ||
1518 skb_pfmemalloc(skb);
1519}
1520
1521static inline void sk_mem_reclaim(struct sock *sk)
1522{
1523 if (!sk_has_account(sk))
1524 return;
1525 if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1526 __sk_mem_reclaim(sk, sk->sk_forward_alloc);
1527}
1528
1529static inline void sk_mem_reclaim_partial(struct sock *sk)
1530{
1531 if (!sk_has_account(sk))
1532 return;
1533 if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1534 __sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1535}
1536
1537static inline void sk_mem_charge(struct sock *sk, int size)
1538{
1539 if (!sk_has_account(sk))
1540 return;
1541 sk->sk_forward_alloc -= size;
1542}
1543
1544static inline void sk_mem_uncharge(struct sock *sk, int size)
1545{
1546 if (!sk_has_account(sk))
1547 return;
1548 sk->sk_forward_alloc += size;
1549
1550 /* Avoid a possible overflow.
1551 * TCP send queues can make this happen, if sk_mem_reclaim()
1552 * is not called and more than 2 GBytes are released at once.
1553 *
1554 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1555 * no need to hold that much forward allocation anyway.
1556 */
1557 if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1558 __sk_mem_reclaim(sk, 1 << 20);
1559}
1560
1561DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key);
1562static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1563{
1564 sk_wmem_queued_add(sk, -skb->truesize);
1565 sk_mem_uncharge(sk, skb->truesize);
1566 if (static_branch_unlikely(&tcp_tx_skb_cache_key) &&
1567 !sk->sk_tx_skb_cache && !skb_cloned(skb)) {
1568 skb_ext_reset(skb);
1569 skb_zcopy_clear(skb, true);
1570 sk->sk_tx_skb_cache = skb;
1571 return;
1572 }
1573 __kfree_skb(skb);
1574}
1575
1576static inline void sock_release_ownership(struct sock *sk)
1577{
1578 if (sk->sk_lock.owned) {
1579 sk->sk_lock.owned = 0;
1580
1581 /* The sk_lock has mutex_unlock() semantics: */
1582 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1583 }
1584}
1585
1586/*
1587 * Macro so as to not evaluate some arguments when
1588 * lockdep is not enabled.
1589 *
1590 * Mark both the sk_lock and the sk_lock.slock as a
1591 * per-address-family lock class.
1592 */
1593#define sock_lock_init_class_and_name(sk, sname, skey, name, key) \
1594do { \
1595 sk->sk_lock.owned = 0; \
1596 init_waitqueue_head(&sk->sk_lock.wq); \
1597 spin_lock_init(&(sk)->sk_lock.slock); \
1598 debug_check_no_locks_freed((void *)&(sk)->sk_lock, \
1599 sizeof((sk)->sk_lock)); \
1600 lockdep_set_class_and_name(&(sk)->sk_lock.slock, \
1601 (skey), (sname)); \
1602 lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0); \
1603} while (0)
1604
1605static inline bool lockdep_sock_is_held(const struct sock *sk)
1606{
1607 return lockdep_is_held(&sk->sk_lock) ||
1608 lockdep_is_held(&sk->sk_lock.slock);
1609}
1610
1611void lock_sock_nested(struct sock *sk, int subclass);
1612
1613static inline void lock_sock(struct sock *sk)
1614{
1615 lock_sock_nested(sk, 0);
1616}
1617
1618void __lock_sock(struct sock *sk);
1619void __release_sock(struct sock *sk);
1620void release_sock(struct sock *sk);
1621
1622/* BH context may only use the following locking interface. */
1623#define bh_lock_sock(__sk) spin_lock(&((__sk)->sk_lock.slock))
1624#define bh_lock_sock_nested(__sk) \
1625 spin_lock_nested(&((__sk)->sk_lock.slock), \
1626 SINGLE_DEPTH_NESTING)
1627#define bh_unlock_sock(__sk) spin_unlock(&((__sk)->sk_lock.slock))
1628
1629bool lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1630
1631/**
1632 * unlock_sock_fast - complement of lock_sock_fast
1633 * @sk: socket
1634 * @slow: slow mode
1635 *
1636 * fast unlock socket for user context.
1637 * If slow mode is on, we call regular release_sock()
1638 */
1639static inline void unlock_sock_fast(struct sock *sk, bool slow)
1640 __releases(&sk->sk_lock.slock)
1641{
1642 if (slow) {
1643 release_sock(sk);
1644 __release(&sk->sk_lock.slock);
1645 } else {
1646 spin_unlock_bh(&sk->sk_lock.slock);
1647 }
1648}
1649
1650/* Used by processes to "lock" a socket state, so that
1651 * interrupts and bottom half handlers won't change it
1652 * from under us. It essentially blocks any incoming
1653 * packets, so that we won't get any new data or any
1654 * packets that change the state of the socket.
1655 *
1656 * While locked, BH processing will add new packets to
1657 * the backlog queue. This queue is processed by the
1658 * owner of the socket lock right before it is released.
1659 *
1660 * Since ~2.3.5 it is also exclusive sleep lock serializing
1661 * accesses from user process context.
1662 */
1663
1664static inline void sock_owned_by_me(const struct sock *sk)
1665{
1666#ifdef CONFIG_LOCKDEP
1667 WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1668#endif
1669}
1670
1671static inline bool sock_owned_by_user(const struct sock *sk)
1672{
1673 sock_owned_by_me(sk);
1674 return sk->sk_lock.owned;
1675}
1676
1677static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1678{
1679 return sk->sk_lock.owned;
1680}
1681
1682/* no reclassification while locks are held */
1683static inline bool sock_allow_reclassification(const struct sock *csk)
1684{
1685 struct sock *sk = (struct sock *)csk;
1686
1687 return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
1688}
1689
1690struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1691 struct proto *prot, int kern);
1692void sk_free(struct sock *sk);
1693void sk_destruct(struct sock *sk);
1694struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1695void sk_free_unlock_clone(struct sock *sk);
1696
1697struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1698 gfp_t priority);
1699void __sock_wfree(struct sk_buff *skb);
1700void sock_wfree(struct sk_buff *skb);
1701struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1702 gfp_t priority);
1703void skb_orphan_partial(struct sk_buff *skb);
1704void sock_rfree(struct sk_buff *skb);
1705void sock_efree(struct sk_buff *skb);
1706#ifdef CONFIG_INET
1707void sock_edemux(struct sk_buff *skb);
1708void sock_pfree(struct sk_buff *skb);
1709#else
1710#define sock_edemux sock_efree
1711#endif
1712
1713int sock_setsockopt(struct socket *sock, int level, int op,
1714 sockptr_t optval, unsigned int optlen);
1715
1716int sock_getsockopt(struct socket *sock, int level, int op,
1717 char __user *optval, int __user *optlen);
1718int sock_gettstamp(struct socket *sock, void __user *userstamp,
1719 bool timeval, bool time32);
1720struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1721 int noblock, int *errcode);
1722struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1723 unsigned long data_len, int noblock,
1724 int *errcode, int max_page_order);
1725void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1726void sock_kfree_s(struct sock *sk, void *mem, int size);
1727void sock_kzfree_s(struct sock *sk, void *mem, int size);
1728void sk_send_sigurg(struct sock *sk);
1729
1730struct sockcm_cookie {
1731 u64 transmit_time;
1732 u32 mark;
1733 u16 tsflags;
1734};
1735
1736static inline void sockcm_init(struct sockcm_cookie *sockc,
1737 const struct sock *sk)
1738{
1739 *sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
1740}
1741
1742int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1743 struct sockcm_cookie *sockc);
1744int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1745 struct sockcm_cookie *sockc);
1746
1747/*
1748 * Functions to fill in entries in struct proto_ops when a protocol
1749 * does not implement a particular function.
1750 */
1751int sock_no_bind(struct socket *, struct sockaddr *, int);
1752int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1753int sock_no_socketpair(struct socket *, struct socket *);
1754int sock_no_accept(struct socket *, struct socket *, int, bool);
1755int sock_no_getname(struct socket *, struct sockaddr *, int);
1756int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1757int sock_no_listen(struct socket *, int);
1758int sock_no_shutdown(struct socket *, int);
1759int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1760int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1761int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1762int sock_no_mmap(struct file *file, struct socket *sock,
1763 struct vm_area_struct *vma);
1764ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1765 size_t size, int flags);
1766ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1767 int offset, size_t size, int flags);
1768
1769/*
1770 * Functions to fill in entries in struct proto_ops when a protocol
1771 * uses the inet style.
1772 */
1773int sock_common_getsockopt(struct socket *sock, int level, int optname,
1774 char __user *optval, int __user *optlen);
1775int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1776 int flags);
1777int sock_common_setsockopt(struct socket *sock, int level, int optname,
1778 sockptr_t optval, unsigned int optlen);
1779
1780void sk_common_release(struct sock *sk);
1781
1782/*
1783 * Default socket callbacks and setup code
1784 */
1785
1786/* Initialise core socket variables */
1787void sock_init_data(struct socket *sock, struct sock *sk);
1788
1789/*
1790 * Socket reference counting postulates.
1791 *
1792 * * Each user of socket SHOULD hold a reference count.
1793 * * Each access point to socket (an hash table bucket, reference from a list,
1794 * running timer, skb in flight MUST hold a reference count.
1795 * * When reference count hits 0, it means it will never increase back.
1796 * * When reference count hits 0, it means that no references from
1797 * outside exist to this socket and current process on current CPU
1798 * is last user and may/should destroy this socket.
1799 * * sk_free is called from any context: process, BH, IRQ. When
1800 * it is called, socket has no references from outside -> sk_free
1801 * may release descendant resources allocated by the socket, but
1802 * to the time when it is called, socket is NOT referenced by any
1803 * hash tables, lists etc.
1804 * * Packets, delivered from outside (from network or from another process)
1805 * and enqueued on receive/error queues SHOULD NOT grab reference count,
1806 * when they sit in queue. Otherwise, packets will leak to hole, when
1807 * socket is looked up by one cpu and unhasing is made by another CPU.
1808 * It is true for udp/raw, netlink (leak to receive and error queues), tcp
1809 * (leak to backlog). Packet socket does all the processing inside
1810 * BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1811 * use separate SMP lock, so that they are prone too.
1812 */
1813
1814/* Ungrab socket and destroy it, if it was the last reference. */
1815static inline void sock_put(struct sock *sk)
1816{
1817 if (refcount_dec_and_test(&sk->sk_refcnt))
1818 sk_free(sk);
1819}
1820/* Generic version of sock_put(), dealing with all sockets
1821 * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1822 */
1823void sock_gen_put(struct sock *sk);
1824
1825int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1826 unsigned int trim_cap, bool refcounted);
1827static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1828 const int nested)
1829{
1830 return __sk_receive_skb(sk, skb, nested, 1, true);
1831}
1832
1833static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1834{
1835 /* sk_tx_queue_mapping accept only upto a 16-bit value */
1836 if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1837 return;
1838 sk->sk_tx_queue_mapping = tx_queue;
1839}
1840
1841#define NO_QUEUE_MAPPING USHRT_MAX
1842
1843static inline void sk_tx_queue_clear(struct sock *sk)
1844{
1845 sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
1846}
1847
1848static inline int sk_tx_queue_get(const struct sock *sk)
1849{
1850 if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
1851 return sk->sk_tx_queue_mapping;
1852
1853 return -1;
1854}
1855
1856static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1857{
1858#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1859 if (skb_rx_queue_recorded(skb)) {
1860 u16 rx_queue = skb_get_rx_queue(skb);
1861
1862 if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING))
1863 return;
1864
1865 sk->sk_rx_queue_mapping = rx_queue;
1866 }
1867#endif
1868}
1869
1870static inline void sk_rx_queue_clear(struct sock *sk)
1871{
1872#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1873 sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING;
1874#endif
1875}
1876
1877static inline int sk_rx_queue_get(const struct sock *sk)
1878{
1879#ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1880 if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING)
1881 return sk->sk_rx_queue_mapping;
1882#endif
1883
1884 return -1;
1885}
1886
1887static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1888{
1889 sk->sk_socket = sock;
1890}
1891
1892static inline wait_queue_head_t *sk_sleep(struct sock *sk)
1893{
1894 BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
1895 return &rcu_dereference_raw(sk->sk_wq)->wait;
1896}
1897/* Detach socket from process context.
1898 * Announce socket dead, detach it from wait queue and inode.
1899 * Note that parent inode held reference count on this struct sock,
1900 * we do not release it in this function, because protocol
1901 * probably wants some additional cleanups or even continuing
1902 * to work with this socket (TCP).
1903 */
1904static inline void sock_orphan(struct sock *sk)
1905{
1906 write_lock_bh(&sk->sk_callback_lock);
1907 sock_set_flag(sk, SOCK_DEAD);
1908 sk_set_socket(sk, NULL);
1909 sk->sk_wq = NULL;
1910 write_unlock_bh(&sk->sk_callback_lock);
1911}
1912
1913static inline void sock_graft(struct sock *sk, struct socket *parent)
1914{
1915 WARN_ON(parent->sk);
1916 write_lock_bh(&sk->sk_callback_lock);
1917 rcu_assign_pointer(sk->sk_wq, &parent->wq);
1918 parent->sk = sk;
1919 sk_set_socket(sk, parent);
1920 sk->sk_uid = SOCK_INODE(parent)->i_uid;
1921 security_sock_graft(sk, parent);
1922 write_unlock_bh(&sk->sk_callback_lock);
1923}
1924
1925kuid_t sock_i_uid(struct sock *sk);
1926unsigned long sock_i_ino(struct sock *sk);
1927
1928static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
1929{
1930 return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
1931}
1932
1933static inline u32 net_tx_rndhash(void)
1934{
1935 u32 v = prandom_u32();
1936
1937 return v ?: 1;
1938}
1939
1940static inline void sk_set_txhash(struct sock *sk)
1941{
1942 /* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
1943 WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
1944}
1945
1946static inline bool sk_rethink_txhash(struct sock *sk)
1947{
1948 if (sk->sk_txhash) {
1949 sk_set_txhash(sk);
1950 return true;
1951 }
1952 return false;
1953}
1954
1955static inline struct dst_entry *
1956__sk_dst_get(struct sock *sk)
1957{
1958 return rcu_dereference_check(sk->sk_dst_cache,
1959 lockdep_sock_is_held(sk));
1960}
1961
1962static inline struct dst_entry *
1963sk_dst_get(struct sock *sk)
1964{
1965 struct dst_entry *dst;
1966
1967 rcu_read_lock();
1968 dst = rcu_dereference(sk->sk_dst_cache);
1969 if (dst && !atomic_inc_not_zero(&dst->__refcnt))
1970 dst = NULL;
1971 rcu_read_unlock();
1972 return dst;
1973}
1974
1975static inline void __dst_negative_advice(struct sock *sk)
1976{
1977 struct dst_entry *ndst, *dst = __sk_dst_get(sk);
1978
1979 if (dst && dst->ops->negative_advice) {
1980 ndst = dst->ops->negative_advice(dst);
1981
1982 if (ndst != dst) {
1983 rcu_assign_pointer(sk->sk_dst_cache, ndst);
1984 sk_tx_queue_clear(sk);
1985 sk->sk_dst_pending_confirm = 0;
1986 }
1987 }
1988}
1989
1990static inline void dst_negative_advice(struct sock *sk)
1991{
1992 sk_rethink_txhash(sk);
1993 __dst_negative_advice(sk);
1994}
1995
1996static inline void
1997__sk_dst_set(struct sock *sk, struct dst_entry *dst)
1998{
1999 struct dst_entry *old_dst;
2000
2001 sk_tx_queue_clear(sk);
2002 sk->sk_dst_pending_confirm = 0;
2003 old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2004 lockdep_sock_is_held(sk));
2005 rcu_assign_pointer(sk->sk_dst_cache, dst);
2006 dst_release(old_dst);
2007}
2008
2009static inline void
2010sk_dst_set(struct sock *sk, struct dst_entry *dst)
2011{
2012 struct dst_entry *old_dst;
2013
2014 sk_tx_queue_clear(sk);
2015 sk->sk_dst_pending_confirm = 0;
2016 old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2017 dst_release(old_dst);
2018}
2019
2020static inline void
2021__sk_dst_reset(struct sock *sk)
2022{
2023 __sk_dst_set(sk, NULL);
2024}
2025
2026static inline void
2027sk_dst_reset(struct sock *sk)
2028{
2029 sk_dst_set(sk, NULL);
2030}
2031
2032struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2033
2034struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2035
2036static inline void sk_dst_confirm(struct sock *sk)
2037{
2038 if (!READ_ONCE(sk->sk_dst_pending_confirm))
2039 WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2040}
2041
2042static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2043{
2044 if (skb_get_dst_pending_confirm(skb)) {
2045 struct sock *sk = skb->sk;
2046 unsigned long now = jiffies;
2047
2048 /* avoid dirtying neighbour */
2049 if (READ_ONCE(n->confirmed) != now)
2050 WRITE_ONCE(n->confirmed, now);
2051 if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2052 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2053 }
2054}
2055
2056bool sk_mc_loop(struct sock *sk);
2057
2058static inline bool sk_can_gso(const struct sock *sk)
2059{
2060 return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2061}
2062
2063void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2064
2065static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
2066{
2067 sk->sk_route_nocaps |= flags;
2068 sk->sk_route_caps &= ~flags;
2069}
2070
2071static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2072 struct iov_iter *from, char *to,
2073 int copy, int offset)
2074{
2075 if (skb->ip_summed == CHECKSUM_NONE) {
2076 __wsum csum = 0;
2077 if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2078 return -EFAULT;
2079 skb->csum = csum_block_add(skb->csum, csum, offset);
2080 } else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2081 if (!copy_from_iter_full_nocache(to, copy, from))
2082 return -EFAULT;
2083 } else if (!copy_from_iter_full(to, copy, from))
2084 return -EFAULT;
2085
2086 return 0;
2087}
2088
2089static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2090 struct iov_iter *from, int copy)
2091{
2092 int err, offset = skb->len;
2093
2094 err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2095 copy, offset);
2096 if (err)
2097 __skb_trim(skb, offset);
2098
2099 return err;
2100}
2101
2102static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2103 struct sk_buff *skb,
2104 struct page *page,
2105 int off, int copy)
2106{
2107 int err;
2108
2109 err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2110 copy, skb->len);
2111 if (err)
2112 return err;
2113
2114 skb->len += copy;
2115 skb->data_len += copy;
2116 skb->truesize += copy;
2117 sk_wmem_queued_add(sk, copy);
2118 sk_mem_charge(sk, copy);
2119 return 0;
2120}
2121
2122/**
2123 * sk_wmem_alloc_get - returns write allocations
2124 * @sk: socket
2125 *
2126 * Return: sk_wmem_alloc minus initial offset of one
2127 */
2128static inline int sk_wmem_alloc_get(const struct sock *sk)
2129{
2130 return refcount_read(&sk->sk_wmem_alloc) - 1;
2131}
2132
2133/**
2134 * sk_rmem_alloc_get - returns read allocations
2135 * @sk: socket
2136 *
2137 * Return: sk_rmem_alloc
2138 */
2139static inline int sk_rmem_alloc_get(const struct sock *sk)
2140{
2141 return atomic_read(&sk->sk_rmem_alloc);
2142}
2143
2144/**
2145 * sk_has_allocations - check if allocations are outstanding
2146 * @sk: socket
2147 *
2148 * Return: true if socket has write or read allocations
2149 */
2150static inline bool sk_has_allocations(const struct sock *sk)
2151{
2152 return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2153}
2154
2155/**
2156 * skwq_has_sleeper - check if there are any waiting processes
2157 * @wq: struct socket_wq
2158 *
2159 * Return: true if socket_wq has waiting processes
2160 *
2161 * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2162 * barrier call. They were added due to the race found within the tcp code.
2163 *
2164 * Consider following tcp code paths::
2165 *
2166 * CPU1 CPU2
2167 * sys_select receive packet
2168 * ... ...
2169 * __add_wait_queue update tp->rcv_nxt
2170 * ... ...
2171 * tp->rcv_nxt check sock_def_readable
2172 * ... {
2173 * schedule rcu_read_lock();
2174 * wq = rcu_dereference(sk->sk_wq);
2175 * if (wq && waitqueue_active(&wq->wait))
2176 * wake_up_interruptible(&wq->wait)
2177 * ...
2178 * }
2179 *
2180 * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2181 * in its cache, and so does the tp->rcv_nxt update on CPU2 side. The CPU1
2182 * could then endup calling schedule and sleep forever if there are no more
2183 * data on the socket.
2184 *
2185 */
2186static inline bool skwq_has_sleeper(struct socket_wq *wq)
2187{
2188 return wq && wq_has_sleeper(&wq->wait);
2189}
2190
2191/**
2192 * sock_poll_wait - place memory barrier behind the poll_wait call.
2193 * @filp: file
2194 * @sock: socket to wait on
2195 * @p: poll_table
2196 *
2197 * See the comments in the wq_has_sleeper function.
2198 */
2199static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2200 poll_table *p)
2201{
2202 if (!poll_does_not_wait(p)) {
2203 poll_wait(filp, &sock->wq.wait, p);
2204 /* We need to be sure we are in sync with the
2205 * socket flags modification.
2206 *
2207 * This memory barrier is paired in the wq_has_sleeper.
2208 */
2209 smp_mb();
2210 }
2211}
2212
2213static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2214{
2215 /* This pairs with WRITE_ONCE() in sk_set_txhash() */
2216 u32 txhash = READ_ONCE(sk->sk_txhash);
2217
2218 if (txhash) {
2219 skb->l4_hash = 1;
2220 skb->hash = txhash;
2221 }
2222}
2223
2224void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2225
2226/*
2227 * Queue a received datagram if it will fit. Stream and sequenced
2228 * protocols can't normally use this as they need to fit buffers in
2229 * and play with them.
2230 *
2231 * Inlined as it's very short and called for pretty much every
2232 * packet ever received.
2233 */
2234static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2235{
2236 skb_orphan(skb);
2237 skb->sk = sk;
2238 skb->destructor = sock_rfree;
2239 atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2240 sk_mem_charge(sk, skb->truesize);
2241}
2242
2243static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2244{
2245 if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2246 skb_orphan(skb);
2247 skb->destructor = sock_efree;
2248 skb->sk = sk;
2249 return true;
2250 }
2251 return false;
2252}
2253
2254void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2255 unsigned long expires);
2256
2257void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2258
2259void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2260
2261int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2262 struct sk_buff *skb, unsigned int flags,
2263 void (*destructor)(struct sock *sk,
2264 struct sk_buff *skb));
2265int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2266int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2267
2268int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2269struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2270
2271/*
2272 * Recover an error report and clear atomically
2273 */
2274
2275static inline int sock_error(struct sock *sk)
2276{
2277 int err;
2278
2279 /* Avoid an atomic operation for the common case.
2280 * This is racy since another cpu/thread can change sk_err under us.
2281 */
2282 if (likely(data_race(!sk->sk_err)))
2283 return 0;
2284
2285 err = xchg(&sk->sk_err, 0);
2286 return -err;
2287}
2288
2289void sk_error_report(struct sock *sk);
2290
2291static inline unsigned long sock_wspace(struct sock *sk)
2292{
2293 int amt = 0;
2294
2295 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2296 amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2297 if (amt < 0)
2298 amt = 0;
2299 }
2300 return amt;
2301}
2302
2303/* Note:
2304 * We use sk->sk_wq_raw, from contexts knowing this
2305 * pointer is not NULL and cannot disappear/change.
2306 */
2307static inline void sk_set_bit(int nr, struct sock *sk)
2308{
2309 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2310 !sock_flag(sk, SOCK_FASYNC))
2311 return;
2312
2313 set_bit(nr, &sk->sk_wq_raw->flags);
2314}
2315
2316static inline void sk_clear_bit(int nr, struct sock *sk)
2317{
2318 if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2319 !sock_flag(sk, SOCK_FASYNC))
2320 return;
2321
2322 clear_bit(nr, &sk->sk_wq_raw->flags);
2323}
2324
2325static inline void sk_wake_async(const struct sock *sk, int how, int band)
2326{
2327 if (sock_flag(sk, SOCK_FASYNC)) {
2328 rcu_read_lock();
2329 sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2330 rcu_read_unlock();
2331 }
2332}
2333
2334/* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2335 * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2336 * Note: for send buffers, TCP works better if we can build two skbs at
2337 * minimum.
2338 */
2339#define TCP_SKB_MIN_TRUESIZE (2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2340
2341#define SOCK_MIN_SNDBUF (TCP_SKB_MIN_TRUESIZE * 2)
2342#define SOCK_MIN_RCVBUF TCP_SKB_MIN_TRUESIZE
2343
2344static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2345{
2346 u32 val;
2347
2348 if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2349 return;
2350
2351 val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2352
2353 WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2354}
2355
2356struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2357 bool force_schedule);
2358
2359/**
2360 * sk_page_frag - return an appropriate page_frag
2361 * @sk: socket
2362 *
2363 * Use the per task page_frag instead of the per socket one for
2364 * optimization when we know that we're in the normal context and owns
2365 * everything that's associated with %current.
2366 *
2367 * gfpflags_allow_blocking() isn't enough here as direct reclaim may nest
2368 * inside other socket operations and end up recursing into sk_page_frag()
2369 * while it's already in use.
2370 *
2371 * Return: a per task page_frag if context allows that,
2372 * otherwise a per socket one.
2373 */
2374static inline struct page_frag *sk_page_frag(struct sock *sk)
2375{
2376 if (gfpflags_normal_context(sk->sk_allocation))
2377 return ¤t->task_frag;
2378
2379 return &sk->sk_frag;
2380}
2381
2382bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2383
2384/*
2385 * Default write policy as shown to user space via poll/select/SIGIO
2386 */
2387static inline bool sock_writeable(const struct sock *sk)
2388{
2389 return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2390}
2391
2392static inline gfp_t gfp_any(void)
2393{
2394 return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2395}
2396
2397static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2398{
2399 return noblock ? 0 : sk->sk_rcvtimeo;
2400}
2401
2402static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2403{
2404 return noblock ? 0 : sk->sk_sndtimeo;
2405}
2406
2407static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2408{
2409 int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2410
2411 return v ?: 1;
2412}
2413
2414/* Alas, with timeout socket operations are not restartable.
2415 * Compare this to poll().
2416 */
2417static inline int sock_intr_errno(long timeo)
2418{
2419 return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2420}
2421
2422struct sock_skb_cb {
2423 u32 dropcount;
2424};
2425
2426/* Store sock_skb_cb at the end of skb->cb[] so protocol families
2427 * using skb->cb[] would keep using it directly and utilize its
2428 * alignement guarantee.
2429 */
2430#define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2431 sizeof(struct sock_skb_cb)))
2432
2433#define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2434 SOCK_SKB_CB_OFFSET))
2435
2436#define sock_skb_cb_check_size(size) \
2437 BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2438
2439static inline void
2440sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2441{
2442 SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2443 atomic_read(&sk->sk_drops) : 0;
2444}
2445
2446static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2447{
2448 int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2449
2450 atomic_add(segs, &sk->sk_drops);
2451}
2452
2453static inline ktime_t sock_read_timestamp(struct sock *sk)
2454{
2455#if BITS_PER_LONG==32
2456 unsigned int seq;
2457 ktime_t kt;
2458
2459 do {
2460 seq = read_seqbegin(&sk->sk_stamp_seq);
2461 kt = sk->sk_stamp;
2462 } while (read_seqretry(&sk->sk_stamp_seq, seq));
2463
2464 return kt;
2465#else
2466 return READ_ONCE(sk->sk_stamp);
2467#endif
2468}
2469
2470static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2471{
2472#if BITS_PER_LONG==32
2473 write_seqlock(&sk->sk_stamp_seq);
2474 sk->sk_stamp = kt;
2475 write_sequnlock(&sk->sk_stamp_seq);
2476#else
2477 WRITE_ONCE(sk->sk_stamp, kt);
2478#endif
2479}
2480
2481void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2482 struct sk_buff *skb);
2483void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2484 struct sk_buff *skb);
2485
2486static inline void
2487sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2488{
2489 ktime_t kt = skb->tstamp;
2490 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2491
2492 /*
2493 * generate control messages if
2494 * - receive time stamping in software requested
2495 * - software time stamp available and wanted
2496 * - hardware time stamps available and wanted
2497 */
2498 if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2499 (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2500 (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2501 (hwtstamps->hwtstamp &&
2502 (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2503 __sock_recv_timestamp(msg, sk, skb);
2504 else
2505 sock_write_timestamp(sk, kt);
2506
2507 if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2508 __sock_recv_wifi_status(msg, sk, skb);
2509}
2510
2511void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2512 struct sk_buff *skb);
2513
2514#define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
2515static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2516 struct sk_buff *skb)
2517{
2518#define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL) | \
2519 (1UL << SOCK_RCVTSTAMP))
2520#define TSFLAGS_ANY (SOF_TIMESTAMPING_SOFTWARE | \
2521 SOF_TIMESTAMPING_RAW_HARDWARE)
2522
2523 if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2524 __sock_recv_ts_and_drops(msg, sk, skb);
2525 else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2526 sock_write_timestamp(sk, skb->tstamp);
2527 else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
2528 sock_write_timestamp(sk, 0);
2529}
2530
2531void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2532
2533/**
2534 * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2535 * @sk: socket sending this packet
2536 * @tsflags: timestamping flags to use
2537 * @tx_flags: completed with instructions for time stamping
2538 * @tskey: filled in with next sk_tskey (not for TCP, which uses seqno)
2539 *
2540 * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2541 */
2542static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2543 __u8 *tx_flags, __u32 *tskey)
2544{
2545 if (unlikely(tsflags)) {
2546 __sock_tx_timestamp(tsflags, tx_flags);
2547 if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2548 tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2549 *tskey = sk->sk_tskey++;
2550 }
2551 if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2552 *tx_flags |= SKBTX_WIFI_STATUS;
2553}
2554
2555static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2556 __u8 *tx_flags)
2557{
2558 _sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2559}
2560
2561static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2562{
2563 _sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2564 &skb_shinfo(skb)->tskey);
2565}
2566
2567DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key);
2568/**
2569 * sk_eat_skb - Release a skb if it is no longer needed
2570 * @sk: socket to eat this skb from
2571 * @skb: socket buffer to eat
2572 *
2573 * This routine must be called with interrupts disabled or with the socket
2574 * locked so that the sk_buff queue operation is ok.
2575*/
2576static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2577{
2578 __skb_unlink(skb, &sk->sk_receive_queue);
2579 if (static_branch_unlikely(&tcp_rx_skb_cache_key) &&
2580 !sk->sk_rx_skb_cache) {
2581 sk->sk_rx_skb_cache = skb;
2582 skb_orphan(skb);
2583 return;
2584 }
2585 __kfree_skb(skb);
2586}
2587
2588static inline
2589struct net *sock_net(const struct sock *sk)
2590{
2591 return read_pnet(&sk->sk_net);
2592}
2593
2594static inline
2595void sock_net_set(struct sock *sk, struct net *net)
2596{
2597 write_pnet(&sk->sk_net, net);
2598}
2599
2600static inline bool
2601skb_sk_is_prefetched(struct sk_buff *skb)
2602{
2603#ifdef CONFIG_INET
2604 return skb->destructor == sock_pfree;
2605#else
2606 return false;
2607#endif /* CONFIG_INET */
2608}
2609
2610/* This helper checks if a socket is a full socket,
2611 * ie _not_ a timewait or request socket.
2612 */
2613static inline bool sk_fullsock(const struct sock *sk)
2614{
2615 return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2616}
2617
2618static inline bool
2619sk_is_refcounted(struct sock *sk)
2620{
2621 /* Only full sockets have sk->sk_flags. */
2622 return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2623}
2624
2625/**
2626 * skb_steal_sock - steal a socket from an sk_buff
2627 * @skb: sk_buff to steal the socket from
2628 * @refcounted: is set to true if the socket is reference-counted
2629 */
2630static inline struct sock *
2631skb_steal_sock(struct sk_buff *skb, bool *refcounted)
2632{
2633 if (skb->sk) {
2634 struct sock *sk = skb->sk;
2635
2636 *refcounted = true;
2637 if (skb_sk_is_prefetched(skb))
2638 *refcounted = sk_is_refcounted(sk);
2639 skb->destructor = NULL;
2640 skb->sk = NULL;
2641 return sk;
2642 }
2643 *refcounted = false;
2644 return NULL;
2645}
2646
2647/* Checks if this SKB belongs to an HW offloaded socket
2648 * and whether any SW fallbacks are required based on dev.
2649 * Check decrypted mark in case skb_orphan() cleared socket.
2650 */
2651static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2652 struct net_device *dev)
2653{
2654#ifdef CONFIG_SOCK_VALIDATE_XMIT
2655 struct sock *sk = skb->sk;
2656
2657 if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2658 skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2659#ifdef CONFIG_TLS_DEVICE
2660 } else if (unlikely(skb->decrypted)) {
2661 pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2662 kfree_skb(skb);
2663 skb = NULL;
2664#endif
2665 }
2666#endif
2667
2668 return skb;
2669}
2670
2671/* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2672 * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2673 */
2674static inline bool sk_listener(const struct sock *sk)
2675{
2676 return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2677}
2678
2679void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2680int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2681 int type);
2682
2683bool sk_ns_capable(const struct sock *sk,
2684 struct user_namespace *user_ns, int cap);
2685bool sk_capable(const struct sock *sk, int cap);
2686bool sk_net_capable(const struct sock *sk, int cap);
2687
2688void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2689
2690/* Take into consideration the size of the struct sk_buff overhead in the
2691 * determination of these values, since that is non-constant across
2692 * platforms. This makes socket queueing behavior and performance
2693 * not depend upon such differences.
2694 */
2695#define _SK_MEM_PACKETS 256
2696#define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
2697#define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2698#define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2699
2700extern __u32 sysctl_wmem_max;
2701extern __u32 sysctl_rmem_max;
2702
2703extern int sysctl_tstamp_allow_data;
2704extern int sysctl_optmem_max;
2705
2706extern __u32 sysctl_wmem_default;
2707extern __u32 sysctl_rmem_default;
2708
2709DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2710
2711static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2712{
2713 /* Does this proto have per netns sysctl_wmem ? */
2714 if (proto->sysctl_wmem_offset)
2715 return *(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset);
2716
2717 return *proto->sysctl_wmem;
2718}
2719
2720static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2721{
2722 /* Does this proto have per netns sysctl_rmem ? */
2723 if (proto->sysctl_rmem_offset)
2724 return *(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset);
2725
2726 return *proto->sysctl_rmem;
2727}
2728
2729/* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2730 * Some wifi drivers need to tweak it to get more chunks.
2731 * They can use this helper from their ndo_start_xmit()
2732 */
2733static inline void sk_pacing_shift_update(struct sock *sk, int val)
2734{
2735 if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2736 return;
2737 WRITE_ONCE(sk->sk_pacing_shift, val);
2738}
2739
2740/* if a socket is bound to a device, check that the given device
2741 * index is either the same or that the socket is bound to an L3
2742 * master device and the given device index is also enslaved to
2743 * that L3 master
2744 */
2745static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2746{
2747 int mdif;
2748
2749 if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
2750 return true;
2751
2752 mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2753 if (mdif && mdif == sk->sk_bound_dev_if)
2754 return true;
2755
2756 return false;
2757}
2758
2759void sock_def_readable(struct sock *sk);
2760
2761int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2762void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2763int sock_set_timestamping(struct sock *sk, int optname,
2764 struct so_timestamping timestamping);
2765
2766void sock_enable_timestamps(struct sock *sk);
2767void sock_no_linger(struct sock *sk);
2768void sock_set_keepalive(struct sock *sk);
2769void sock_set_priority(struct sock *sk, u32 priority);
2770void sock_set_rcvbuf(struct sock *sk, int val);
2771void sock_set_mark(struct sock *sk, u32 val);
2772void sock_set_reuseaddr(struct sock *sk);
2773void sock_set_reuseport(struct sock *sk);
2774void sock_set_sndtimeo(struct sock *sk, s64 secs);
2775
2776int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2777
2778#endif /* _SOCK_H */