1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * INET		An implementation of the TCP/IP protocol suite for the LINUX
4  *		operating system.  INET is implemented using the  BSD Socket
5  *		interface as the means of communication with the user level.
6  *
7  *		Definitions for the AF_INET socket handler.
8  *
9  * Version:	@(#)sock.h	1.0.4	05/13/93
10  *
11  * Authors:	Ross Biro
12  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13  *		Corey Minyard <wf-rch!minyard@relay.EU.net>
14  *		Florian La Roche <flla@stud.uni-sb.de>
15  *
16  * Fixes:
17  *		Alan Cox	:	Volatiles in skbuff pointers. See
18  *					skbuff comments. May be overdone,
19  *					better to prove they can be removed
20  *					than the reverse.
21  *		Alan Cox	:	Added a zapped field for tcp to note
22  *					a socket is reset and must stay shut up
23  *		Alan Cox	:	New fields for options
24  *	Pauline Middelink	:	identd support
25  *		Alan Cox	:	Eliminate low level recv/recvfrom
26  *		David S. Miller	:	New socket lookup architecture.
27  *              Steve Whitehouse:       Default routines for sock_ops
28  *              Arnaldo C. Melo :	removed net_pinfo, tp_pinfo and made
29  *              			protinfo be just a void pointer, as the
30  *              			protocol specific parts were moved to
31  *              			respective headers and ipv4/v6, etc now
32  *              			use private slabcaches for its socks
33  *              Pedro Hortas	:	New flags field for socket options
34  */
35 #ifndef _SOCK_H
36 #define _SOCK_H
37 
38 #include <linux/hardirq.h>
39 #include <linux/kernel.h>
40 #include <linux/list.h>
41 #include <linux/list_nulls.h>
42 #include <linux/timer.h>
43 #include <linux/cache.h>
44 #include <linux/bitops.h>
45 #include <linux/lockdep.h>
46 #include <linux/netdevice.h>
47 #include <linux/skbuff.h>	/* struct sk_buff */
48 #include <linux/mm.h>
49 #include <linux/security.h>
50 #include <linux/slab.h>
51 #include <linux/uaccess.h>
52 #include <linux/page_counter.h>
53 #include <linux/memcontrol.h>
54 #include <linux/static_key.h>
55 #include <linux/sched.h>
56 #include <linux/wait.h>
57 #include <linux/cgroup-defs.h>
58 #include <linux/rbtree.h>
59 #include <linux/rculist_nulls.h>
60 #include <linux/poll.h>
61 #include <linux/sockptr.h>
62 #include <linux/indirect_call_wrapper.h>
63 #include <linux/atomic.h>
64 #include <linux/refcount.h>
65 #include <linux/llist.h>
66 #include <net/dst.h>
67 #include <net/checksum.h>
68 #include <net/tcp_states.h>
69 #include <linux/net_tstamp.h>
70 #include <net/l3mdev.h>
71 #include <uapi/linux/socket.h>
72 
73 /*
74  * This structure really needs to be cleaned up.
75  * Most of it is for TCP, and not used by any of
76  * the other protocols.
77  */
78 
79 /* Define this to get the SOCK_DBG debugging facility. */
80 #define SOCK_DEBUGGING
81 #ifdef SOCK_DEBUGGING
82 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
83 					printk(KERN_DEBUG msg); } while (0)
84 #else
85 /* Validate arguments and do nothing */
86 static inline __printf(2, 3)
SOCK_DEBUG(const struct sock * sk,const char * msg,...)87 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
88 {
89 }
90 #endif
91 
92 /* This is the per-socket lock.  The spinlock provides a synchronization
93  * between user contexts and software interrupt processing, whereas the
94  * mini-semaphore synchronizes multiple users amongst themselves.
95  */
96 typedef struct {
97 	spinlock_t		slock;
98 	int			owned;
99 	wait_queue_head_t	wq;
100 	/*
101 	 * We express the mutex-alike socket_lock semantics
102 	 * to the lock validator by explicitly managing
103 	 * the slock as a lock variant (in addition to
104 	 * the slock itself):
105 	 */
106 #ifdef CONFIG_DEBUG_LOCK_ALLOC
107 	struct lockdep_map dep_map;
108 #endif
109 } socket_lock_t;
110 
111 struct sock;
112 struct proto;
113 struct net;
114 
115 typedef __u32 __bitwise __portpair;
116 typedef __u64 __bitwise __addrpair;
117 
118 /**
119  *	struct sock_common - minimal network layer representation of sockets
120  *	@skc_daddr: Foreign IPv4 addr
121  *	@skc_rcv_saddr: Bound local IPv4 addr
122  *	@skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
123  *	@skc_hash: hash value used with various protocol lookup tables
124  *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
125  *	@skc_dport: placeholder for inet_dport/tw_dport
126  *	@skc_num: placeholder for inet_num/tw_num
127  *	@skc_portpair: __u32 union of @skc_dport & @skc_num
128  *	@skc_family: network address family
129  *	@skc_state: Connection state
130  *	@skc_reuse: %SO_REUSEADDR setting
131  *	@skc_reuseport: %SO_REUSEPORT setting
132  *	@skc_ipv6only: socket is IPV6 only
133  *	@skc_net_refcnt: socket is using net ref counting
134  *	@skc_bound_dev_if: bound device index if != 0
135  *	@skc_bind_node: bind hash linkage for various protocol lookup tables
136  *	@skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
137  *	@skc_prot: protocol handlers inside a network family
138  *	@skc_net: reference to the network namespace of this socket
139  *	@skc_v6_daddr: IPV6 destination address
140  *	@skc_v6_rcv_saddr: IPV6 source address
141  *	@skc_cookie: socket's cookie value
142  *	@skc_node: main hash linkage for various protocol lookup tables
143  *	@skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
144  *	@skc_tx_queue_mapping: tx queue number for this connection
145  *	@skc_rx_queue_mapping: rx queue number for this connection
146  *	@skc_flags: place holder for sk_flags
147  *		%SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
148  *		%SO_OOBINLINE settings, %SO_TIMESTAMPING settings
149  *	@skc_listener: connection request listener socket (aka rsk_listener)
150  *		[union with @skc_flags]
151  *	@skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
152  *		[union with @skc_flags]
153  *	@skc_incoming_cpu: record/match cpu processing incoming packets
154  *	@skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
155  *		[union with @skc_incoming_cpu]
156  *	@skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
157  *		[union with @skc_incoming_cpu]
158  *	@skc_refcnt: reference count
159  *
160  *	This is the minimal network layer representation of sockets, the header
161  *	for struct sock and struct inet_timewait_sock.
162  */
163 struct sock_common {
164 	union {
165 		__addrpair	skc_addrpair;
166 		struct {
167 			__be32	skc_daddr;
168 			__be32	skc_rcv_saddr;
169 		};
170 	};
171 	union  {
172 		unsigned int	skc_hash;
173 		__u16		skc_u16hashes[2];
174 	};
175 	/* skc_dport && skc_num must be grouped as well */
176 	union {
177 		__portpair	skc_portpair;
178 		struct {
179 			__be16	skc_dport;
180 			__u16	skc_num;
181 		};
182 	};
183 
184 	unsigned short		skc_family;
185 	volatile unsigned char	skc_state;
186 	unsigned char		skc_reuse:4;
187 	unsigned char		skc_reuseport:1;
188 	unsigned char		skc_ipv6only:1;
189 	unsigned char		skc_net_refcnt:1;
190 	int			skc_bound_dev_if;
191 	union {
192 		struct hlist_node	skc_bind_node;
193 		struct hlist_node	skc_portaddr_node;
194 	};
195 	struct proto		*skc_prot;
196 	possible_net_t		skc_net;
197 
198 #if IS_ENABLED(CONFIG_IPV6)
199 	struct in6_addr		skc_v6_daddr;
200 	struct in6_addr		skc_v6_rcv_saddr;
201 #endif
202 
203 	atomic64_t		skc_cookie;
204 
205 	/* following fields are padding to force
206 	 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
207 	 * assuming IPV6 is enabled. We use this padding differently
208 	 * for different kind of 'sockets'
209 	 */
210 	union {
211 		unsigned long	skc_flags;
212 		struct sock	*skc_listener; /* request_sock */
213 		struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
214 	};
215 	/*
216 	 * fields between dontcopy_begin/dontcopy_end
217 	 * are not copied in sock_copy()
218 	 */
219 	/* private: */
220 	int			skc_dontcopy_begin[0];
221 	/* public: */
222 	union {
223 		struct hlist_node	skc_node;
224 		struct hlist_nulls_node skc_nulls_node;
225 	};
226 	unsigned short		skc_tx_queue_mapping;
227 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
228 	unsigned short		skc_rx_queue_mapping;
229 #endif
230 	union {
231 		int		skc_incoming_cpu;
232 		u32		skc_rcv_wnd;
233 		u32		skc_tw_rcv_nxt; /* struct tcp_timewait_sock  */
234 	};
235 
236 	refcount_t		skc_refcnt;
237 	/* private: */
238 	int                     skc_dontcopy_end[0];
239 	union {
240 		u32		skc_rxhash;
241 		u32		skc_window_clamp;
242 		u32		skc_tw_snd_nxt; /* struct tcp_timewait_sock */
243 	};
244 	/* public: */
245 };
246 
247 struct bpf_local_storage;
248 struct sk_filter;
249 
250 /**
251   *	struct sock - network layer representation of sockets
252   *	@__sk_common: shared layout with inet_timewait_sock
253   *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
254   *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
255   *	@sk_lock:	synchronizer
256   *	@sk_kern_sock: True if sock is using kernel lock classes
257   *	@sk_rcvbuf: size of receive buffer in bytes
258   *	@sk_wq: sock wait queue and async head
259   *	@sk_rx_dst: receive input route used by early demux
260   *	@sk_rx_dst_ifindex: ifindex for @sk_rx_dst
261   *	@sk_rx_dst_cookie: cookie for @sk_rx_dst
262   *	@sk_dst_cache: destination cache
263   *	@sk_dst_pending_confirm: need to confirm neighbour
264   *	@sk_policy: flow policy
265   *	@sk_receive_queue: incoming packets
266   *	@sk_wmem_alloc: transmit queue bytes committed
267   *	@sk_tsq_flags: TCP Small Queues flags
268   *	@sk_write_queue: Packet sending queue
269   *	@sk_omem_alloc: "o" is "option" or "other"
270   *	@sk_wmem_queued: persistent queue size
271   *	@sk_forward_alloc: space allocated forward
272   *	@sk_reserved_mem: space reserved and non-reclaimable for the socket
273   *	@sk_napi_id: id of the last napi context to receive data for sk
274   *	@sk_ll_usec: usecs to busypoll when there is no data
275   *	@sk_allocation: allocation mode
276   *	@sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
277   *	@sk_pacing_status: Pacing status (requested, handled by sch_fq)
278   *	@sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
279   *	@sk_sndbuf: size of send buffer in bytes
280   *	@__sk_flags_offset: empty field used to determine location of bitfield
281   *	@sk_padding: unused element for alignment
282   *	@sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
283   *	@sk_no_check_rx: allow zero checksum in RX packets
284   *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
285   *	@sk_gso_disabled: if set, NETIF_F_GSO_MASK is forbidden.
286   *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
287   *	@sk_gso_max_size: Maximum GSO segment size to build
288   *	@sk_gso_max_segs: Maximum number of GSO segments
289   *	@sk_pacing_shift: scaling factor for TCP Small Queues
290   *	@sk_lingertime: %SO_LINGER l_linger setting
291   *	@sk_backlog: always used with the per-socket spinlock held
292   *	@sk_callback_lock: used with the callbacks in the end of this struct
293   *	@sk_error_queue: rarely used
294   *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
295   *			  IPV6_ADDRFORM for instance)
296   *	@sk_err: last error
297   *	@sk_err_soft: errors that don't cause failure but are the cause of a
298   *		      persistent failure not just 'timed out'
299   *	@sk_drops: raw/udp drops counter
300   *	@sk_ack_backlog: current listen backlog
301   *	@sk_max_ack_backlog: listen backlog set in listen()
302   *	@sk_uid: user id of owner
303   *	@sk_prefer_busy_poll: prefer busypolling over softirq processing
304   *	@sk_busy_poll_budget: napi processing budget when busypolling
305   *	@sk_priority: %SO_PRIORITY setting
306   *	@sk_type: socket type (%SOCK_STREAM, etc)
307   *	@sk_protocol: which protocol this socket belongs in this network family
308   *	@sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred
309   *	@sk_peer_pid: &struct pid for this socket's peer
310   *	@sk_peer_cred: %SO_PEERCRED setting
311   *	@sk_rcvlowat: %SO_RCVLOWAT setting
312   *	@sk_rcvtimeo: %SO_RCVTIMEO setting
313   *	@sk_sndtimeo: %SO_SNDTIMEO setting
314   *	@sk_txhash: computed flow hash for use on transmit
315   *	@sk_txrehash: enable TX hash rethink
316   *	@sk_filter: socket filtering instructions
317   *	@sk_timer: sock cleanup timer
318   *	@sk_stamp: time stamp of last packet received
319   *	@sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
320   *	@sk_tsflags: SO_TIMESTAMPING flags
321   *	@sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
322   *	              for timestamping
323   *	@sk_tskey: counter to disambiguate concurrent tstamp requests
324   *	@sk_zckey: counter to order MSG_ZEROCOPY notifications
325   *	@sk_socket: Identd and reporting IO signals
326   *	@sk_user_data: RPC layer private data
327   *	@sk_frag: cached page frag
328   *	@sk_peek_off: current peek_offset value
329   *	@sk_send_head: front of stuff to transmit
330   *	@tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
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   *	@ns_tracker: tracker for netns reference
351   */
352 struct sock {
353 	/*
354 	 * Now struct inet_timewait_sock also uses sock_common, so please just
355 	 * don't add nothing before this first member (__sk_common) --acme
356 	 */
357 	struct sock_common	__sk_common;
358 #define sk_node			__sk_common.skc_node
359 #define sk_nulls_node		__sk_common.skc_nulls_node
360 #define sk_refcnt		__sk_common.skc_refcnt
361 #define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
362 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
363 #define sk_rx_queue_mapping	__sk_common.skc_rx_queue_mapping
364 #endif
365 
366 #define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
367 #define sk_dontcopy_end		__sk_common.skc_dontcopy_end
368 #define sk_hash			__sk_common.skc_hash
369 #define sk_portpair		__sk_common.skc_portpair
370 #define sk_num			__sk_common.skc_num
371 #define sk_dport		__sk_common.skc_dport
372 #define sk_addrpair		__sk_common.skc_addrpair
373 #define sk_daddr		__sk_common.skc_daddr
374 #define sk_rcv_saddr		__sk_common.skc_rcv_saddr
375 #define sk_family		__sk_common.skc_family
376 #define sk_state		__sk_common.skc_state
377 #define sk_reuse		__sk_common.skc_reuse
378 #define sk_reuseport		__sk_common.skc_reuseport
379 #define sk_ipv6only		__sk_common.skc_ipv6only
380 #define sk_net_refcnt		__sk_common.skc_net_refcnt
381 #define sk_bound_dev_if		__sk_common.skc_bound_dev_if
382 #define sk_bind_node		__sk_common.skc_bind_node
383 #define sk_prot			__sk_common.skc_prot
384 #define sk_net			__sk_common.skc_net
385 #define sk_v6_daddr		__sk_common.skc_v6_daddr
386 #define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
387 #define sk_cookie		__sk_common.skc_cookie
388 #define sk_incoming_cpu		__sk_common.skc_incoming_cpu
389 #define sk_flags		__sk_common.skc_flags
390 #define sk_rxhash		__sk_common.skc_rxhash
391 
392 	/* early demux fields */
393 	struct dst_entry __rcu	*sk_rx_dst;
394 	int			sk_rx_dst_ifindex;
395 	u32			sk_rx_dst_cookie;
396 
397 	socket_lock_t		sk_lock;
398 	atomic_t		sk_drops;
399 	int			sk_rcvlowat;
400 	struct sk_buff_head	sk_error_queue;
401 	struct sk_buff_head	sk_receive_queue;
402 	/*
403 	 * The backlog queue is special, it is always used with
404 	 * the per-socket spinlock held and requires low latency
405 	 * access. Therefore we special case it's implementation.
406 	 * Note : rmem_alloc is in this structure to fill a hole
407 	 * on 64bit arches, not because its logically part of
408 	 * backlog.
409 	 */
410 	struct {
411 		atomic_t	rmem_alloc;
412 		int		len;
413 		struct sk_buff	*head;
414 		struct sk_buff	*tail;
415 	} sk_backlog;
416 
417 #define sk_rmem_alloc sk_backlog.rmem_alloc
418 
419 	int			sk_forward_alloc;
420 	u32			sk_reserved_mem;
421 #ifdef CONFIG_NET_RX_BUSY_POLL
422 	unsigned int		sk_ll_usec;
423 	/* ===== mostly read cache line ===== */
424 	unsigned int		sk_napi_id;
425 #endif
426 	int			sk_rcvbuf;
427 
428 	struct sk_filter __rcu	*sk_filter;
429 	union {
430 		struct socket_wq __rcu	*sk_wq;
431 		/* private: */
432 		struct socket_wq	*sk_wq_raw;
433 		/* public: */
434 	};
435 #ifdef CONFIG_XFRM
436 	struct xfrm_policy __rcu *sk_policy[2];
437 #endif
438 
439 	struct dst_entry __rcu	*sk_dst_cache;
440 	atomic_t		sk_omem_alloc;
441 	int			sk_sndbuf;
442 
443 	/* ===== cache line for TX ===== */
444 	int			sk_wmem_queued;
445 	refcount_t		sk_wmem_alloc;
446 	unsigned long		sk_tsq_flags;
447 	union {
448 		struct sk_buff	*sk_send_head;
449 		struct rb_root	tcp_rtx_queue;
450 	};
451 	struct sk_buff_head	sk_write_queue;
452 	__s32			sk_peek_off;
453 	int			sk_write_pending;
454 	__u32			sk_dst_pending_confirm;
455 	u32			sk_pacing_status; /* see enum sk_pacing */
456 	long			sk_sndtimeo;
457 	struct timer_list	sk_timer;
458 	__u32			sk_priority;
459 	__u32			sk_mark;
460 	unsigned long		sk_pacing_rate; /* bytes per second */
461 	unsigned long		sk_max_pacing_rate;
462 	struct page_frag	sk_frag;
463 	netdev_features_t	sk_route_caps;
464 	int			sk_gso_type;
465 	unsigned int		sk_gso_max_size;
466 	gfp_t			sk_allocation;
467 	__u32			sk_txhash;
468 
469 	/*
470 	 * Because of non atomicity rules, all
471 	 * changes are protected by socket lock.
472 	 */
473 	u8			sk_gso_disabled : 1,
474 				sk_kern_sock : 1,
475 				sk_no_check_tx : 1,
476 				sk_no_check_rx : 1,
477 				sk_userlocks : 4;
478 	u8			sk_pacing_shift;
479 	u16			sk_type;
480 	u16			sk_protocol;
481 	u16			sk_gso_max_segs;
482 	unsigned long	        sk_lingertime;
483 	struct proto		*sk_prot_creator;
484 	rwlock_t		sk_callback_lock;
485 	int			sk_err,
486 				sk_err_soft;
487 	u32			sk_ack_backlog;
488 	u32			sk_max_ack_backlog;
489 	kuid_t			sk_uid;
490 	u8			sk_txrehash;
491 #ifdef CONFIG_NET_RX_BUSY_POLL
492 	u8			sk_prefer_busy_poll;
493 	u16			sk_busy_poll_budget;
494 #endif
495 	spinlock_t		sk_peer_lock;
496 	int			sk_bind_phc;
497 	struct pid		*sk_peer_pid;
498 	const struct cred	*sk_peer_cred;
499 
500 	long			sk_rcvtimeo;
501 	ktime_t			sk_stamp;
502 #if BITS_PER_LONG==32
503 	seqlock_t		sk_stamp_seq;
504 #endif
505 	u16			sk_tsflags;
506 	u8			sk_shutdown;
507 	atomic_t		sk_tskey;
508 	atomic_t		sk_zckey;
509 
510 	u8			sk_clockid;
511 	u8			sk_txtime_deadline_mode : 1,
512 				sk_txtime_report_errors : 1,
513 				sk_txtime_unused : 6;
514 
515 	struct socket		*sk_socket;
516 	void			*sk_user_data;
517 #ifdef CONFIG_SECURITY
518 	void			*sk_security;
519 #endif
520 	struct sock_cgroup_data	sk_cgrp_data;
521 	struct mem_cgroup	*sk_memcg;
522 	void			(*sk_state_change)(struct sock *sk);
523 	void			(*sk_data_ready)(struct sock *sk);
524 	void			(*sk_write_space)(struct sock *sk);
525 	void			(*sk_error_report)(struct sock *sk);
526 	int			(*sk_backlog_rcv)(struct sock *sk,
527 						  struct sk_buff *skb);
528 #ifdef CONFIG_SOCK_VALIDATE_XMIT
529 	struct sk_buff*		(*sk_validate_xmit_skb)(struct sock *sk,
530 							struct net_device *dev,
531 							struct sk_buff *skb);
532 #endif
533 	void                    (*sk_destruct)(struct sock *sk);
534 	struct sock_reuseport __rcu	*sk_reuseport_cb;
535 #ifdef CONFIG_BPF_SYSCALL
536 	struct bpf_local_storage __rcu	*sk_bpf_storage;
537 #endif
538 	struct rcu_head		sk_rcu;
539 	netns_tracker		ns_tracker;
540 };
541 
542 enum sk_pacing {
543 	SK_PACING_NONE		= 0,
544 	SK_PACING_NEEDED	= 1,
545 	SK_PACING_FQ		= 2,
546 };
547 
548 /* flag bits in sk_user_data
549  *
550  * - SK_USER_DATA_NOCOPY:      Pointer stored in sk_user_data might
551  *   not be suitable for copying when cloning the socket. For instance,
552  *   it can point to a reference counted object. sk_user_data bottom
553  *   bit is set if pointer must not be copied.
554  *
555  * - SK_USER_DATA_BPF:         Mark whether sk_user_data field is
556  *   managed/owned by a BPF reuseport array. This bit should be set
557  *   when sk_user_data's sk is added to the bpf's reuseport_array.
558  *
559  * - SK_USER_DATA_PSOCK:       Mark whether pointer stored in
560  *   sk_user_data points to psock type. This bit should be set
561  *   when sk_user_data is assigned to a psock object.
562  */
563 #define SK_USER_DATA_NOCOPY	1UL
564 #define SK_USER_DATA_BPF	2UL
565 #define SK_USER_DATA_PSOCK	4UL
566 #define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
567 				  SK_USER_DATA_PSOCK)
568 
569 /**
570  * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
571  * @sk: socket
572  */
sk_user_data_is_nocopy(const struct sock * sk)573 static inline bool sk_user_data_is_nocopy(const struct sock *sk)
574 {
575 	return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
576 }
577 
578 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
579 
580 /**
581  * __rcu_dereference_sk_user_data_with_flags - return the pointer
582  * only if argument flags all has been set in sk_user_data. Otherwise
583  * return NULL
584  *
585  * @sk: socket
586  * @flags: flag bits
587  */
588 static inline void *
__rcu_dereference_sk_user_data_with_flags(const struct sock * sk,uintptr_t flags)589 __rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
590 					  uintptr_t flags)
591 {
592 	uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
593 
594 	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
595 
596 	if ((sk_user_data & flags) == flags)
597 		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
598 	return NULL;
599 }
600 
601 #define rcu_dereference_sk_user_data(sk)				\
602 	__rcu_dereference_sk_user_data_with_flags(sk, 0)
603 #define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags)		\
604 ({									\
605 	uintptr_t __tmp1 = (uintptr_t)(ptr),				\
606 		  __tmp2 = (uintptr_t)(flags);				\
607 	WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK);			\
608 	WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK);			\
609 	rcu_assign_pointer(__sk_user_data((sk)),			\
610 			   __tmp1 | __tmp2);				\
611 })
612 #define rcu_assign_sk_user_data(sk, ptr)				\
613 	__rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
614 
615 static inline
sock_net(const struct sock * sk)616 struct net *sock_net(const struct sock *sk)
617 {
618 	return read_pnet(&sk->sk_net);
619 }
620 
621 static inline
sock_net_set(struct sock * sk,struct net * net)622 void sock_net_set(struct sock *sk, struct net *net)
623 {
624 	write_pnet(&sk->sk_net, net);
625 }
626 
627 /*
628  * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
629  * or not whether his port will be reused by someone else. SK_FORCE_REUSE
630  * on a socket means that the socket will reuse everybody else's port
631  * without looking at the other's sk_reuse value.
632  */
633 
634 #define SK_NO_REUSE	0
635 #define SK_CAN_REUSE	1
636 #define SK_FORCE_REUSE	2
637 
638 int sk_set_peek_off(struct sock *sk, int val);
639 
sk_peek_offset(struct sock * sk,int flags)640 static inline int sk_peek_offset(struct sock *sk, int flags)
641 {
642 	if (unlikely(flags & MSG_PEEK)) {
643 		return READ_ONCE(sk->sk_peek_off);
644 	}
645 
646 	return 0;
647 }
648 
sk_peek_offset_bwd(struct sock * sk,int val)649 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
650 {
651 	s32 off = READ_ONCE(sk->sk_peek_off);
652 
653 	if (unlikely(off >= 0)) {
654 		off = max_t(s32, off - val, 0);
655 		WRITE_ONCE(sk->sk_peek_off, off);
656 	}
657 }
658 
sk_peek_offset_fwd(struct sock * sk,int val)659 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
660 {
661 	sk_peek_offset_bwd(sk, -val);
662 }
663 
664 /*
665  * Hashed lists helper routines
666  */
sk_entry(const struct hlist_node * node)667 static inline struct sock *sk_entry(const struct hlist_node *node)
668 {
669 	return hlist_entry(node, struct sock, sk_node);
670 }
671 
__sk_head(const struct hlist_head * head)672 static inline struct sock *__sk_head(const struct hlist_head *head)
673 {
674 	return hlist_entry(head->first, struct sock, sk_node);
675 }
676 
sk_head(const struct hlist_head * head)677 static inline struct sock *sk_head(const struct hlist_head *head)
678 {
679 	return hlist_empty(head) ? NULL : __sk_head(head);
680 }
681 
__sk_nulls_head(const struct hlist_nulls_head * head)682 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
683 {
684 	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
685 }
686 
sk_nulls_head(const struct hlist_nulls_head * head)687 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
688 {
689 	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
690 }
691 
sk_next(const struct sock * sk)692 static inline struct sock *sk_next(const struct sock *sk)
693 {
694 	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
695 }
696 
sk_nulls_next(const struct sock * sk)697 static inline struct sock *sk_nulls_next(const struct sock *sk)
698 {
699 	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
700 		hlist_nulls_entry(sk->sk_nulls_node.next,
701 				  struct sock, sk_nulls_node) :
702 		NULL;
703 }
704 
sk_unhashed(const struct sock * sk)705 static inline bool sk_unhashed(const struct sock *sk)
706 {
707 	return hlist_unhashed(&sk->sk_node);
708 }
709 
sk_hashed(const struct sock * sk)710 static inline bool sk_hashed(const struct sock *sk)
711 {
712 	return !sk_unhashed(sk);
713 }
714 
sk_node_init(struct hlist_node * node)715 static inline void sk_node_init(struct hlist_node *node)
716 {
717 	node->pprev = NULL;
718 }
719 
sk_nulls_node_init(struct hlist_nulls_node * node)720 static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
721 {
722 	node->pprev = NULL;
723 }
724 
__sk_del_node(struct sock * sk)725 static inline void __sk_del_node(struct sock *sk)
726 {
727 	__hlist_del(&sk->sk_node);
728 }
729 
730 /* NB: equivalent to hlist_del_init_rcu */
__sk_del_node_init(struct sock * sk)731 static inline bool __sk_del_node_init(struct sock *sk)
732 {
733 	if (sk_hashed(sk)) {
734 		__sk_del_node(sk);
735 		sk_node_init(&sk->sk_node);
736 		return true;
737 	}
738 	return false;
739 }
740 
741 /* Grab socket reference count. This operation is valid only
742    when sk is ALREADY grabbed f.e. it is found in hash table
743    or a list and the lookup is made under lock preventing hash table
744    modifications.
745  */
746 
sock_hold(struct sock * sk)747 static __always_inline void sock_hold(struct sock *sk)
748 {
749 	refcount_inc(&sk->sk_refcnt);
750 }
751 
752 /* Ungrab socket in the context, which assumes that socket refcnt
753    cannot hit zero, f.e. it is true in context of any socketcall.
754  */
__sock_put(struct sock * sk)755 static __always_inline void __sock_put(struct sock *sk)
756 {
757 	refcount_dec(&sk->sk_refcnt);
758 }
759 
sk_del_node_init(struct sock * sk)760 static inline bool sk_del_node_init(struct sock *sk)
761 {
762 	bool rc = __sk_del_node_init(sk);
763 
764 	if (rc) {
765 		/* paranoid for a while -acme */
766 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
767 		__sock_put(sk);
768 	}
769 	return rc;
770 }
771 #define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
772 
__sk_nulls_del_node_init_rcu(struct sock * sk)773 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
774 {
775 	if (sk_hashed(sk)) {
776 		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
777 		return true;
778 	}
779 	return false;
780 }
781 
sk_nulls_del_node_init_rcu(struct sock * sk)782 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
783 {
784 	bool rc = __sk_nulls_del_node_init_rcu(sk);
785 
786 	if (rc) {
787 		/* paranoid for a while -acme */
788 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
789 		__sock_put(sk);
790 	}
791 	return rc;
792 }
793 
__sk_add_node(struct sock * sk,struct hlist_head * list)794 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
795 {
796 	hlist_add_head(&sk->sk_node, list);
797 }
798 
sk_add_node(struct sock * sk,struct hlist_head * list)799 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
800 {
801 	sock_hold(sk);
802 	__sk_add_node(sk, list);
803 }
804 
sk_add_node_rcu(struct sock * sk,struct hlist_head * list)805 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
806 {
807 	sock_hold(sk);
808 	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
809 	    sk->sk_family == AF_INET6)
810 		hlist_add_tail_rcu(&sk->sk_node, list);
811 	else
812 		hlist_add_head_rcu(&sk->sk_node, list);
813 }
814 
sk_add_node_tail_rcu(struct sock * sk,struct hlist_head * list)815 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
816 {
817 	sock_hold(sk);
818 	hlist_add_tail_rcu(&sk->sk_node, list);
819 }
820 
__sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)821 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
822 {
823 	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
824 }
825 
__sk_nulls_add_node_tail_rcu(struct sock * sk,struct hlist_nulls_head * list)826 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
827 {
828 	hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
829 }
830 
sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)831 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
832 {
833 	sock_hold(sk);
834 	__sk_nulls_add_node_rcu(sk, list);
835 }
836 
__sk_del_bind_node(struct sock * sk)837 static inline void __sk_del_bind_node(struct sock *sk)
838 {
839 	__hlist_del(&sk->sk_bind_node);
840 }
841 
sk_add_bind_node(struct sock * sk,struct hlist_head * list)842 static inline void sk_add_bind_node(struct sock *sk,
843 					struct hlist_head *list)
844 {
845 	hlist_add_head(&sk->sk_bind_node, list);
846 }
847 
848 #define sk_for_each(__sk, list) \
849 	hlist_for_each_entry(__sk, list, sk_node)
850 #define sk_for_each_rcu(__sk, list) \
851 	hlist_for_each_entry_rcu(__sk, list, sk_node)
852 #define sk_nulls_for_each(__sk, node, list) \
853 	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
854 #define sk_nulls_for_each_rcu(__sk, node, list) \
855 	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
856 #define sk_for_each_from(__sk) \
857 	hlist_for_each_entry_from(__sk, sk_node)
858 #define sk_nulls_for_each_from(__sk, node) \
859 	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
860 		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
861 #define sk_for_each_safe(__sk, tmp, list) \
862 	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
863 #define sk_for_each_bound(__sk, list) \
864 	hlist_for_each_entry(__sk, list, sk_bind_node)
865 
866 /**
867  * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
868  * @tpos:	the type * to use as a loop cursor.
869  * @pos:	the &struct hlist_node to use as a loop cursor.
870  * @head:	the head for your list.
871  * @offset:	offset of hlist_node within the struct.
872  *
873  */
874 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
875 	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
876 	     pos != NULL &&						       \
877 		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
878 	     pos = rcu_dereference(hlist_next_rcu(pos)))
879 
sk_user_ns(struct sock * sk)880 static inline struct user_namespace *sk_user_ns(struct sock *sk)
881 {
882 	/* Careful only use this in a context where these parameters
883 	 * can not change and must all be valid, such as recvmsg from
884 	 * userspace.
885 	 */
886 	return sk->sk_socket->file->f_cred->user_ns;
887 }
888 
889 /* Sock flags */
890 enum sock_flags {
891 	SOCK_DEAD,
892 	SOCK_DONE,
893 	SOCK_URGINLINE,
894 	SOCK_KEEPOPEN,
895 	SOCK_LINGER,
896 	SOCK_DESTROY,
897 	SOCK_BROADCAST,
898 	SOCK_TIMESTAMP,
899 	SOCK_ZAPPED,
900 	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
901 	SOCK_DBG, /* %SO_DEBUG setting */
902 	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
903 	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
904 	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
905 	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
906 	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
907 	SOCK_FASYNC, /* fasync() active */
908 	SOCK_RXQ_OVFL,
909 	SOCK_ZEROCOPY, /* buffers from userspace */
910 	SOCK_WIFI_STATUS, /* push wifi status to userspace */
911 	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
912 		     * Will use last 4 bytes of packet sent from
913 		     * user-space instead.
914 		     */
915 	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
916 	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
917 	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
918 	SOCK_TXTIME,
919 	SOCK_XDP, /* XDP is attached */
920 	SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
921 	SOCK_RCVMARK, /* Receive SO_MARK  ancillary data with packet */
922 };
923 
924 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
925 
sock_copy_flags(struct sock * nsk,struct sock * osk)926 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
927 {
928 	nsk->sk_flags = osk->sk_flags;
929 }
930 
sock_set_flag(struct sock * sk,enum sock_flags flag)931 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
932 {
933 	__set_bit(flag, &sk->sk_flags);
934 }
935 
sock_reset_flag(struct sock * sk,enum sock_flags flag)936 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
937 {
938 	__clear_bit(flag, &sk->sk_flags);
939 }
940 
sock_valbool_flag(struct sock * sk,enum sock_flags bit,int valbool)941 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
942 				     int valbool)
943 {
944 	if (valbool)
945 		sock_set_flag(sk, bit);
946 	else
947 		sock_reset_flag(sk, bit);
948 }
949 
sock_flag(const struct sock * sk,enum sock_flags flag)950 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
951 {
952 	return test_bit(flag, &sk->sk_flags);
953 }
954 
955 #ifdef CONFIG_NET
956 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
sk_memalloc_socks(void)957 static inline int sk_memalloc_socks(void)
958 {
959 	return static_branch_unlikely(&memalloc_socks_key);
960 }
961 
962 void __receive_sock(struct file *file);
963 #else
964 
sk_memalloc_socks(void)965 static inline int sk_memalloc_socks(void)
966 {
967 	return 0;
968 }
969 
__receive_sock(struct file * file)970 static inline void __receive_sock(struct file *file)
971 { }
972 #endif
973 
sk_gfp_mask(const struct sock * sk,gfp_t gfp_mask)974 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
975 {
976 	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
977 }
978 
sk_acceptq_removed(struct sock * sk)979 static inline void sk_acceptq_removed(struct sock *sk)
980 {
981 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
982 }
983 
sk_acceptq_added(struct sock * sk)984 static inline void sk_acceptq_added(struct sock *sk)
985 {
986 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
987 }
988 
989 /* Note: If you think the test should be:
990  *	return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
991  * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
992  */
sk_acceptq_is_full(const struct sock * sk)993 static inline bool sk_acceptq_is_full(const struct sock *sk)
994 {
995 	return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
996 }
997 
998 /*
999  * Compute minimal free write space needed to queue new packets.
1000  */
sk_stream_min_wspace(const struct sock * sk)1001 static inline int sk_stream_min_wspace(const struct sock *sk)
1002 {
1003 	return READ_ONCE(sk->sk_wmem_queued) >> 1;
1004 }
1005 
sk_stream_wspace(const struct sock * sk)1006 static inline int sk_stream_wspace(const struct sock *sk)
1007 {
1008 	return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
1009 }
1010 
sk_wmem_queued_add(struct sock * sk,int val)1011 static inline void sk_wmem_queued_add(struct sock *sk, int val)
1012 {
1013 	WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
1014 }
1015 
1016 void sk_stream_write_space(struct sock *sk);
1017 
1018 /* OOB backlog add */
__sk_add_backlog(struct sock * sk,struct sk_buff * skb)1019 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
1020 {
1021 	/* dont let skb dst not refcounted, we are going to leave rcu lock */
1022 	skb_dst_force(skb);
1023 
1024 	if (!sk->sk_backlog.tail)
1025 		WRITE_ONCE(sk->sk_backlog.head, skb);
1026 	else
1027 		sk->sk_backlog.tail->next = skb;
1028 
1029 	WRITE_ONCE(sk->sk_backlog.tail, skb);
1030 	skb->next = NULL;
1031 }
1032 
1033 /*
1034  * Take into account size of receive queue and backlog queue
1035  * Do not take into account this skb truesize,
1036  * to allow even a single big packet to come.
1037  */
sk_rcvqueues_full(const struct sock * sk,unsigned int limit)1038 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
1039 {
1040 	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
1041 
1042 	return qsize > limit;
1043 }
1044 
1045 /* The per-socket spinlock must be held here. */
sk_add_backlog(struct sock * sk,struct sk_buff * skb,unsigned int limit)1046 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1047 					      unsigned int limit)
1048 {
1049 	if (sk_rcvqueues_full(sk, limit))
1050 		return -ENOBUFS;
1051 
1052 	/*
1053 	 * If the skb was allocated from pfmemalloc reserves, only
1054 	 * allow SOCK_MEMALLOC sockets to use it as this socket is
1055 	 * helping free memory
1056 	 */
1057 	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1058 		return -ENOMEM;
1059 
1060 	__sk_add_backlog(sk, skb);
1061 	sk->sk_backlog.len += skb->truesize;
1062 	return 0;
1063 }
1064 
1065 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1066 
1067 INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
1068 INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
1069 
sk_backlog_rcv(struct sock * sk,struct sk_buff * skb)1070 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1071 {
1072 	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1073 		return __sk_backlog_rcv(sk, skb);
1074 
1075 	return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
1076 				  tcp_v6_do_rcv,
1077 				  tcp_v4_do_rcv,
1078 				  sk, skb);
1079 }
1080 
sk_incoming_cpu_update(struct sock * sk)1081 static inline void sk_incoming_cpu_update(struct sock *sk)
1082 {
1083 	int cpu = raw_smp_processor_id();
1084 
1085 	if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1086 		WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1087 }
1088 
sock_rps_record_flow_hash(__u32 hash)1089 static inline void sock_rps_record_flow_hash(__u32 hash)
1090 {
1091 #ifdef CONFIG_RPS
1092 	struct rps_sock_flow_table *sock_flow_table;
1093 
1094 	rcu_read_lock();
1095 	sock_flow_table = rcu_dereference(rps_sock_flow_table);
1096 	rps_record_sock_flow(sock_flow_table, hash);
1097 	rcu_read_unlock();
1098 #endif
1099 }
1100 
sock_rps_record_flow(const struct sock * sk)1101 static inline void sock_rps_record_flow(const struct sock *sk)
1102 {
1103 #ifdef CONFIG_RPS
1104 	if (static_branch_unlikely(&rfs_needed)) {
1105 		/* Reading sk->sk_rxhash might incur an expensive cache line
1106 		 * miss.
1107 		 *
1108 		 * TCP_ESTABLISHED does cover almost all states where RFS
1109 		 * might be useful, and is cheaper [1] than testing :
1110 		 *	IPv4: inet_sk(sk)->inet_daddr
1111 		 * 	IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
1112 		 * OR	an additional socket flag
1113 		 * [1] : sk_state and sk_prot are in the same cache line.
1114 		 */
1115 		if (sk->sk_state == TCP_ESTABLISHED)
1116 			sock_rps_record_flow_hash(sk->sk_rxhash);
1117 	}
1118 #endif
1119 }
1120 
sock_rps_save_rxhash(struct sock * sk,const struct sk_buff * skb)1121 static inline void sock_rps_save_rxhash(struct sock *sk,
1122 					const struct sk_buff *skb)
1123 {
1124 #ifdef CONFIG_RPS
1125 	if (unlikely(sk->sk_rxhash != skb->hash))
1126 		sk->sk_rxhash = skb->hash;
1127 #endif
1128 }
1129 
sock_rps_reset_rxhash(struct sock * sk)1130 static inline void sock_rps_reset_rxhash(struct sock *sk)
1131 {
1132 #ifdef CONFIG_RPS
1133 	sk->sk_rxhash = 0;
1134 #endif
1135 }
1136 
1137 #define sk_wait_event(__sk, __timeo, __condition, __wait)		\
1138 	({	int __rc;						\
1139 		release_sock(__sk);					\
1140 		__rc = __condition;					\
1141 		if (!__rc) {						\
1142 			*(__timeo) = wait_woken(__wait,			\
1143 						TASK_INTERRUPTIBLE,	\
1144 						*(__timeo));		\
1145 		}							\
1146 		sched_annotate_sleep();					\
1147 		lock_sock(__sk);					\
1148 		__rc = __condition;					\
1149 		__rc;							\
1150 	})
1151 
1152 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1153 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1154 void sk_stream_wait_close(struct sock *sk, long timeo_p);
1155 int sk_stream_error(struct sock *sk, int flags, int err);
1156 void sk_stream_kill_queues(struct sock *sk);
1157 void sk_set_memalloc(struct sock *sk);
1158 void sk_clear_memalloc(struct sock *sk);
1159 
1160 void __sk_flush_backlog(struct sock *sk);
1161 
sk_flush_backlog(struct sock * sk)1162 static inline bool sk_flush_backlog(struct sock *sk)
1163 {
1164 	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1165 		__sk_flush_backlog(sk);
1166 		return true;
1167 	}
1168 	return false;
1169 }
1170 
1171 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1172 
1173 struct request_sock_ops;
1174 struct timewait_sock_ops;
1175 struct inet_hashinfo;
1176 struct raw_hashinfo;
1177 struct smc_hashinfo;
1178 struct module;
1179 struct sk_psock;
1180 
1181 /*
1182  * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1183  * un-modified. Special care is taken when initializing object to zero.
1184  */
sk_prot_clear_nulls(struct sock * sk,int size)1185 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1186 {
1187 	if (offsetof(struct sock, sk_node.next) != 0)
1188 		memset(sk, 0, offsetof(struct sock, sk_node.next));
1189 	memset(&sk->sk_node.pprev, 0,
1190 	       size - offsetof(struct sock, sk_node.pprev));
1191 }
1192 
1193 /* Networking protocol blocks we attach to sockets.
1194  * socket layer -> transport layer interface
1195  */
1196 struct proto {
1197 	void			(*close)(struct sock *sk,
1198 					long timeout);
1199 	int			(*pre_connect)(struct sock *sk,
1200 					struct sockaddr *uaddr,
1201 					int addr_len);
1202 	int			(*connect)(struct sock *sk,
1203 					struct sockaddr *uaddr,
1204 					int addr_len);
1205 	int			(*disconnect)(struct sock *sk, int flags);
1206 
1207 	struct sock *		(*accept)(struct sock *sk, int flags, int *err,
1208 					  bool kern);
1209 
1210 	int			(*ioctl)(struct sock *sk, int cmd,
1211 					 unsigned long arg);
1212 	int			(*init)(struct sock *sk);
1213 	void			(*destroy)(struct sock *sk);
1214 	void			(*shutdown)(struct sock *sk, int how);
1215 	int			(*setsockopt)(struct sock *sk, int level,
1216 					int optname, sockptr_t optval,
1217 					unsigned int optlen);
1218 	int			(*getsockopt)(struct sock *sk, int level,
1219 					int optname, char __user *optval,
1220 					int __user *option);
1221 	void			(*keepalive)(struct sock *sk, int valbool);
1222 #ifdef CONFIG_COMPAT
1223 	int			(*compat_ioctl)(struct sock *sk,
1224 					unsigned int cmd, unsigned long arg);
1225 #endif
1226 	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
1227 					   size_t len);
1228 	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
1229 					   size_t len, int flags, int *addr_len);
1230 	int			(*sendpage)(struct sock *sk, struct page *page,
1231 					int offset, size_t size, int flags);
1232 	int			(*bind)(struct sock *sk,
1233 					struct sockaddr *addr, int addr_len);
1234 	int			(*bind_add)(struct sock *sk,
1235 					struct sockaddr *addr, int addr_len);
1236 
1237 	int			(*backlog_rcv) (struct sock *sk,
1238 						struct sk_buff *skb);
1239 	bool			(*bpf_bypass_getsockopt)(int level,
1240 							 int optname);
1241 
1242 	void		(*release_cb)(struct sock *sk);
1243 
1244 	/* Keeping track of sk's, looking them up, and port selection methods. */
1245 	int			(*hash)(struct sock *sk);
1246 	void			(*unhash)(struct sock *sk);
1247 	void			(*rehash)(struct sock *sk);
1248 	int			(*get_port)(struct sock *sk, unsigned short snum);
1249 	void			(*put_port)(struct sock *sk);
1250 #ifdef CONFIG_BPF_SYSCALL
1251 	int			(*psock_update_sk_prot)(struct sock *sk,
1252 							struct sk_psock *psock,
1253 							bool restore);
1254 #endif
1255 
1256 	/* Keeping track of sockets in use */
1257 #ifdef CONFIG_PROC_FS
1258 	unsigned int		inuse_idx;
1259 #endif
1260 
1261 #if IS_ENABLED(CONFIG_MPTCP)
1262 	int			(*forward_alloc_get)(const struct sock *sk);
1263 #endif
1264 
1265 	bool			(*stream_memory_free)(const struct sock *sk, int wake);
1266 	bool			(*sock_is_readable)(struct sock *sk);
1267 	/* Memory pressure */
1268 	void			(*enter_memory_pressure)(struct sock *sk);
1269 	void			(*leave_memory_pressure)(struct sock *sk);
1270 	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
1271 	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
1272 
1273 	/*
1274 	 * Pressure flag: try to collapse.
1275 	 * Technical note: it is used by multiple contexts non atomically.
1276 	 * All the __sk_mem_schedule() is of this nature: accounting
1277 	 * is strict, actions are advisory and have some latency.
1278 	 */
1279 	unsigned long		*memory_pressure;
1280 	long			*sysctl_mem;
1281 
1282 	int			*sysctl_wmem;
1283 	int			*sysctl_rmem;
1284 	u32			sysctl_wmem_offset;
1285 	u32			sysctl_rmem_offset;
1286 
1287 	int			max_header;
1288 	bool			no_autobind;
1289 
1290 	struct kmem_cache	*slab;
1291 	unsigned int		obj_size;
1292 	slab_flags_t		slab_flags;
1293 	unsigned int		useroffset;	/* Usercopy region offset */
1294 	unsigned int		usersize;	/* Usercopy region size */
1295 
1296 	unsigned int __percpu	*orphan_count;
1297 
1298 	struct request_sock_ops	*rsk_prot;
1299 	struct timewait_sock_ops *twsk_prot;
1300 
1301 	union {
1302 		struct inet_hashinfo	*hashinfo;
1303 		struct udp_table	*udp_table;
1304 		struct raw_hashinfo	*raw_hash;
1305 		struct smc_hashinfo	*smc_hash;
1306 	} h;
1307 
1308 	struct module		*owner;
1309 
1310 	char			name[32];
1311 
1312 	struct list_head	node;
1313 #ifdef SOCK_REFCNT_DEBUG
1314 	atomic_t		socks;
1315 #endif
1316 	int			(*diag_destroy)(struct sock *sk, int err);
1317 } __randomize_layout;
1318 
1319 int proto_register(struct proto *prot, int alloc_slab);
1320 void proto_unregister(struct proto *prot);
1321 int sock_load_diag_module(int family, int protocol);
1322 
1323 #ifdef SOCK_REFCNT_DEBUG
sk_refcnt_debug_inc(struct sock * sk)1324 static inline void sk_refcnt_debug_inc(struct sock *sk)
1325 {
1326 	atomic_inc(&sk->sk_prot->socks);
1327 }
1328 
sk_refcnt_debug_dec(struct sock * sk)1329 static inline void sk_refcnt_debug_dec(struct sock *sk)
1330 {
1331 	atomic_dec(&sk->sk_prot->socks);
1332 	printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1333 	       sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1334 }
1335 
sk_refcnt_debug_release(const struct sock * sk)1336 static inline void sk_refcnt_debug_release(const struct sock *sk)
1337 {
1338 	if (refcount_read(&sk->sk_refcnt) != 1)
1339 		printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1340 		       sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1341 }
1342 #else /* SOCK_REFCNT_DEBUG */
1343 #define sk_refcnt_debug_inc(sk) do { } while (0)
1344 #define sk_refcnt_debug_dec(sk) do { } while (0)
1345 #define sk_refcnt_debug_release(sk) do { } while (0)
1346 #endif /* SOCK_REFCNT_DEBUG */
1347 
1348 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1349 
sk_forward_alloc_get(const struct sock * sk)1350 static inline int sk_forward_alloc_get(const struct sock *sk)
1351 {
1352 #if IS_ENABLED(CONFIG_MPTCP)
1353 	if (sk->sk_prot->forward_alloc_get)
1354 		return sk->sk_prot->forward_alloc_get(sk);
1355 #endif
1356 	return sk->sk_forward_alloc;
1357 }
1358 
__sk_stream_memory_free(const struct sock * sk,int wake)1359 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1360 {
1361 	if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1362 		return false;
1363 
1364 	return sk->sk_prot->stream_memory_free ?
1365 		INDIRECT_CALL_INET_1(sk->sk_prot->stream_memory_free,
1366 				     tcp_stream_memory_free, sk, wake) : true;
1367 }
1368 
sk_stream_memory_free(const struct sock * sk)1369 static inline bool sk_stream_memory_free(const struct sock *sk)
1370 {
1371 	return __sk_stream_memory_free(sk, 0);
1372 }
1373 
__sk_stream_is_writeable(const struct sock * sk,int wake)1374 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1375 {
1376 	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1377 	       __sk_stream_memory_free(sk, wake);
1378 }
1379 
sk_stream_is_writeable(const struct sock * sk)1380 static inline bool sk_stream_is_writeable(const struct sock *sk)
1381 {
1382 	return __sk_stream_is_writeable(sk, 0);
1383 }
1384 
sk_under_cgroup_hierarchy(struct sock * sk,struct cgroup * ancestor)1385 static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1386 					    struct cgroup *ancestor)
1387 {
1388 #ifdef CONFIG_SOCK_CGROUP_DATA
1389 	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1390 				    ancestor);
1391 #else
1392 	return -ENOTSUPP;
1393 #endif
1394 }
1395 
sk_has_memory_pressure(const struct sock * sk)1396 static inline bool sk_has_memory_pressure(const struct sock *sk)
1397 {
1398 	return sk->sk_prot->memory_pressure != NULL;
1399 }
1400 
sk_under_memory_pressure(const struct sock * sk)1401 static inline bool sk_under_memory_pressure(const struct sock *sk)
1402 {
1403 	if (!sk->sk_prot->memory_pressure)
1404 		return false;
1405 
1406 	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1407 	    mem_cgroup_under_socket_pressure(sk->sk_memcg))
1408 		return true;
1409 
1410 	return !!*sk->sk_prot->memory_pressure;
1411 }
1412 
1413 static inline long
sk_memory_allocated(const struct sock * sk)1414 sk_memory_allocated(const struct sock *sk)
1415 {
1416 	return atomic_long_read(sk->sk_prot->memory_allocated);
1417 }
1418 
1419 static inline long
sk_memory_allocated_add(struct sock * sk,int amt)1420 sk_memory_allocated_add(struct sock *sk, int amt)
1421 {
1422 	return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1423 }
1424 
1425 static inline void
sk_memory_allocated_sub(struct sock * sk,int amt)1426 sk_memory_allocated_sub(struct sock *sk, int amt)
1427 {
1428 	atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1429 }
1430 
1431 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1432 
sk_sockets_allocated_dec(struct sock * sk)1433 static inline void sk_sockets_allocated_dec(struct sock *sk)
1434 {
1435 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1436 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1437 }
1438 
sk_sockets_allocated_inc(struct sock * sk)1439 static inline void sk_sockets_allocated_inc(struct sock *sk)
1440 {
1441 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1442 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1443 }
1444 
1445 static inline u64
sk_sockets_allocated_read_positive(struct sock * sk)1446 sk_sockets_allocated_read_positive(struct sock *sk)
1447 {
1448 	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1449 }
1450 
1451 static inline int
proto_sockets_allocated_sum_positive(struct proto * prot)1452 proto_sockets_allocated_sum_positive(struct proto *prot)
1453 {
1454 	return percpu_counter_sum_positive(prot->sockets_allocated);
1455 }
1456 
1457 static inline long
proto_memory_allocated(struct proto * prot)1458 proto_memory_allocated(struct proto *prot)
1459 {
1460 	return atomic_long_read(prot->memory_allocated);
1461 }
1462 
1463 static inline bool
proto_memory_pressure(struct proto * prot)1464 proto_memory_pressure(struct proto *prot)
1465 {
1466 	if (!prot->memory_pressure)
1467 		return false;
1468 	return !!*prot->memory_pressure;
1469 }
1470 
1471 
1472 #ifdef CONFIG_PROC_FS
1473 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
1474 struct prot_inuse {
1475 	int all;
1476 	int val[PROTO_INUSE_NR];
1477 };
1478 
sock_prot_inuse_add(const struct net * net,const struct proto * prot,int val)1479 static inline void sock_prot_inuse_add(const struct net *net,
1480 				       const struct proto *prot, int val)
1481 {
1482 	this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
1483 }
1484 
sock_inuse_add(const struct net * net,int val)1485 static inline void sock_inuse_add(const struct net *net, int val)
1486 {
1487 	this_cpu_add(net->core.prot_inuse->all, val);
1488 }
1489 
1490 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1491 int sock_inuse_get(struct net *net);
1492 #else
sock_prot_inuse_add(const struct net * net,const struct proto * prot,int val)1493 static inline void sock_prot_inuse_add(const struct net *net,
1494 				       const struct proto *prot, int val)
1495 {
1496 }
1497 
sock_inuse_add(const struct net * net,int val)1498 static inline void sock_inuse_add(const struct net *net, int val)
1499 {
1500 }
1501 #endif
1502 
1503 
1504 /* With per-bucket locks this operation is not-atomic, so that
1505  * this version is not worse.
1506  */
__sk_prot_rehash(struct sock * sk)1507 static inline int __sk_prot_rehash(struct sock *sk)
1508 {
1509 	sk->sk_prot->unhash(sk);
1510 	return sk->sk_prot->hash(sk);
1511 }
1512 
1513 /* About 10 seconds */
1514 #define SOCK_DESTROY_TIME (10*HZ)
1515 
1516 /* Sockets 0-1023 can't be bound to unless you are superuser */
1517 #define PROT_SOCK	1024
1518 
1519 #define SHUTDOWN_MASK	3
1520 #define RCV_SHUTDOWN	1
1521 #define SEND_SHUTDOWN	2
1522 
1523 #define SOCK_BINDADDR_LOCK	4
1524 #define SOCK_BINDPORT_LOCK	8
1525 
1526 struct socket_alloc {
1527 	struct socket socket;
1528 	struct inode vfs_inode;
1529 };
1530 
SOCKET_I(struct inode * inode)1531 static inline struct socket *SOCKET_I(struct inode *inode)
1532 {
1533 	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1534 }
1535 
SOCK_INODE(struct socket * socket)1536 static inline struct inode *SOCK_INODE(struct socket *socket)
1537 {
1538 	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1539 }
1540 
1541 /*
1542  * Functions for memory accounting
1543  */
1544 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1545 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1546 void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1547 void __sk_mem_reclaim(struct sock *sk, int amount);
1548 
1549 /* We used to have PAGE_SIZE here, but systems with 64KB pages
1550  * do not necessarily have 16x time more memory than 4KB ones.
1551  */
1552 #define SK_MEM_QUANTUM 4096
1553 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1554 #define SK_MEM_SEND	0
1555 #define SK_MEM_RECV	1
1556 
1557 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
sk_prot_mem_limits(const struct sock * sk,int index)1558 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1559 {
1560 	long val = READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1561 
1562 #if PAGE_SIZE > SK_MEM_QUANTUM
1563 	val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1564 #elif PAGE_SIZE < SK_MEM_QUANTUM
1565 	val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1566 #endif
1567 	return val;
1568 }
1569 
sk_mem_pages(int amt)1570 static inline int sk_mem_pages(int amt)
1571 {
1572 	return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1573 }
1574 
sk_has_account(struct sock * sk)1575 static inline bool sk_has_account(struct sock *sk)
1576 {
1577 	/* return true if protocol supports memory accounting */
1578 	return !!sk->sk_prot->memory_allocated;
1579 }
1580 
sk_wmem_schedule(struct sock * sk,int size)1581 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1582 {
1583 	int delta;
1584 
1585 	if (!sk_has_account(sk))
1586 		return true;
1587 	delta = size - sk->sk_forward_alloc;
1588 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND);
1589 }
1590 
1591 static inline bool
sk_rmem_schedule(struct sock * sk,struct sk_buff * skb,int size)1592 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1593 {
1594 	int delta;
1595 
1596 	if (!sk_has_account(sk))
1597 		return true;
1598 	delta = size - sk->sk_forward_alloc;
1599 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) ||
1600 		skb_pfmemalloc(skb);
1601 }
1602 
sk_unused_reserved_mem(const struct sock * sk)1603 static inline int sk_unused_reserved_mem(const struct sock *sk)
1604 {
1605 	int unused_mem;
1606 
1607 	if (likely(!sk->sk_reserved_mem))
1608 		return 0;
1609 
1610 	unused_mem = sk->sk_reserved_mem - sk->sk_wmem_queued -
1611 			atomic_read(&sk->sk_rmem_alloc);
1612 
1613 	return unused_mem > 0 ? unused_mem : 0;
1614 }
1615 
sk_mem_reclaim(struct sock * sk)1616 static inline void sk_mem_reclaim(struct sock *sk)
1617 {
1618 	int reclaimable;
1619 
1620 	if (!sk_has_account(sk))
1621 		return;
1622 
1623 	reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1624 
1625 	if (reclaimable >= SK_MEM_QUANTUM)
1626 		__sk_mem_reclaim(sk, reclaimable);
1627 }
1628 
sk_mem_reclaim_final(struct sock * sk)1629 static inline void sk_mem_reclaim_final(struct sock *sk)
1630 {
1631 	sk->sk_reserved_mem = 0;
1632 	sk_mem_reclaim(sk);
1633 }
1634 
sk_mem_reclaim_partial(struct sock * sk)1635 static inline void sk_mem_reclaim_partial(struct sock *sk)
1636 {
1637 	int reclaimable;
1638 
1639 	if (!sk_has_account(sk))
1640 		return;
1641 
1642 	reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1643 
1644 	if (reclaimable > SK_MEM_QUANTUM)
1645 		__sk_mem_reclaim(sk, reclaimable - 1);
1646 }
1647 
sk_mem_charge(struct sock * sk,int size)1648 static inline void sk_mem_charge(struct sock *sk, int size)
1649 {
1650 	if (!sk_has_account(sk))
1651 		return;
1652 	sk->sk_forward_alloc -= size;
1653 }
1654 
1655 /* the following macros control memory reclaiming in sk_mem_uncharge()
1656  */
1657 #define SK_RECLAIM_THRESHOLD	(1 << 21)
1658 #define SK_RECLAIM_CHUNK	(1 << 20)
1659 
sk_mem_uncharge(struct sock * sk,int size)1660 static inline void sk_mem_uncharge(struct sock *sk, int size)
1661 {
1662 	int reclaimable;
1663 
1664 	if (!sk_has_account(sk))
1665 		return;
1666 	sk->sk_forward_alloc += size;
1667 	reclaimable = sk->sk_forward_alloc - sk_unused_reserved_mem(sk);
1668 
1669 	/* Avoid a possible overflow.
1670 	 * TCP send queues can make this happen, if sk_mem_reclaim()
1671 	 * is not called and more than 2 GBytes are released at once.
1672 	 *
1673 	 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1674 	 * no need to hold that much forward allocation anyway.
1675 	 */
1676 	if (unlikely(reclaimable >= SK_RECLAIM_THRESHOLD))
1677 		__sk_mem_reclaim(sk, SK_RECLAIM_CHUNK);
1678 }
1679 
1680 /*
1681  * Macro so as to not evaluate some arguments when
1682  * lockdep is not enabled.
1683  *
1684  * Mark both the sk_lock and the sk_lock.slock as a
1685  * per-address-family lock class.
1686  */
1687 #define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1688 do {									\
1689 	sk->sk_lock.owned = 0;						\
1690 	init_waitqueue_head(&sk->sk_lock.wq);				\
1691 	spin_lock_init(&(sk)->sk_lock.slock);				\
1692 	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1693 			sizeof((sk)->sk_lock));				\
1694 	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1695 				(skey), (sname));				\
1696 	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1697 } while (0)
1698 
lockdep_sock_is_held(const struct sock * sk)1699 static inline bool lockdep_sock_is_held(const struct sock *sk)
1700 {
1701 	return lockdep_is_held(&sk->sk_lock) ||
1702 	       lockdep_is_held(&sk->sk_lock.slock);
1703 }
1704 
1705 void lock_sock_nested(struct sock *sk, int subclass);
1706 
lock_sock(struct sock * sk)1707 static inline void lock_sock(struct sock *sk)
1708 {
1709 	lock_sock_nested(sk, 0);
1710 }
1711 
1712 void __lock_sock(struct sock *sk);
1713 void __release_sock(struct sock *sk);
1714 void release_sock(struct sock *sk);
1715 
1716 /* BH context may only use the following locking interface. */
1717 #define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1718 #define bh_lock_sock_nested(__sk) \
1719 				spin_lock_nested(&((__sk)->sk_lock.slock), \
1720 				SINGLE_DEPTH_NESTING)
1721 #define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1722 
1723 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1724 
1725 /**
1726  * lock_sock_fast - fast version of lock_sock
1727  * @sk: socket
1728  *
1729  * This version should be used for very small section, where process wont block
1730  * return false if fast path is taken:
1731  *
1732  *   sk_lock.slock locked, owned = 0, BH disabled
1733  *
1734  * return true if slow path is taken:
1735  *
1736  *   sk_lock.slock unlocked, owned = 1, BH enabled
1737  */
lock_sock_fast(struct sock * sk)1738 static inline bool lock_sock_fast(struct sock *sk)
1739 {
1740 	/* The sk_lock has mutex_lock() semantics here. */
1741 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1742 
1743 	return __lock_sock_fast(sk);
1744 }
1745 
1746 /* fast socket lock variant for caller already holding a [different] socket lock */
lock_sock_fast_nested(struct sock * sk)1747 static inline bool lock_sock_fast_nested(struct sock *sk)
1748 {
1749 	mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1750 
1751 	return __lock_sock_fast(sk);
1752 }
1753 
1754 /**
1755  * unlock_sock_fast - complement of lock_sock_fast
1756  * @sk: socket
1757  * @slow: slow mode
1758  *
1759  * fast unlock socket for user context.
1760  * If slow mode is on, we call regular release_sock()
1761  */
unlock_sock_fast(struct sock * sk,bool slow)1762 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1763 	__releases(&sk->sk_lock.slock)
1764 {
1765 	if (slow) {
1766 		release_sock(sk);
1767 		__release(&sk->sk_lock.slock);
1768 	} else {
1769 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1770 		spin_unlock_bh(&sk->sk_lock.slock);
1771 	}
1772 }
1773 
1774 /* Used by processes to "lock" a socket state, so that
1775  * interrupts and bottom half handlers won't change it
1776  * from under us. It essentially blocks any incoming
1777  * packets, so that we won't get any new data or any
1778  * packets that change the state of the socket.
1779  *
1780  * While locked, BH processing will add new packets to
1781  * the backlog queue.  This queue is processed by the
1782  * owner of the socket lock right before it is released.
1783  *
1784  * Since ~2.3.5 it is also exclusive sleep lock serializing
1785  * accesses from user process context.
1786  */
1787 
sock_owned_by_me(const struct sock * sk)1788 static inline void sock_owned_by_me(const struct sock *sk)
1789 {
1790 #ifdef CONFIG_LOCKDEP
1791 	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1792 #endif
1793 }
1794 
sock_owned_by_user(const struct sock * sk)1795 static inline bool sock_owned_by_user(const struct sock *sk)
1796 {
1797 	sock_owned_by_me(sk);
1798 	return sk->sk_lock.owned;
1799 }
1800 
sock_owned_by_user_nocheck(const struct sock * sk)1801 static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1802 {
1803 	return sk->sk_lock.owned;
1804 }
1805 
sock_release_ownership(struct sock * sk)1806 static inline void sock_release_ownership(struct sock *sk)
1807 {
1808 	if (sock_owned_by_user_nocheck(sk)) {
1809 		sk->sk_lock.owned = 0;
1810 
1811 		/* The sk_lock has mutex_unlock() semantics: */
1812 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1813 	}
1814 }
1815 
1816 /* no reclassification while locks are held */
sock_allow_reclassification(const struct sock * csk)1817 static inline bool sock_allow_reclassification(const struct sock *csk)
1818 {
1819 	struct sock *sk = (struct sock *)csk;
1820 
1821 	return !sock_owned_by_user_nocheck(sk) &&
1822 		!spin_is_locked(&sk->sk_lock.slock);
1823 }
1824 
1825 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1826 		      struct proto *prot, int kern);
1827 void sk_free(struct sock *sk);
1828 void sk_destruct(struct sock *sk);
1829 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1830 void sk_free_unlock_clone(struct sock *sk);
1831 
1832 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1833 			     gfp_t priority);
1834 void __sock_wfree(struct sk_buff *skb);
1835 void sock_wfree(struct sk_buff *skb);
1836 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1837 			     gfp_t priority);
1838 void skb_orphan_partial(struct sk_buff *skb);
1839 void sock_rfree(struct sk_buff *skb);
1840 void sock_efree(struct sk_buff *skb);
1841 #ifdef CONFIG_INET
1842 void sock_edemux(struct sk_buff *skb);
1843 void sock_pfree(struct sk_buff *skb);
1844 #else
1845 #define sock_edemux sock_efree
1846 #endif
1847 
1848 int sock_setsockopt(struct socket *sock, int level, int op,
1849 		    sockptr_t optval, unsigned int optlen);
1850 
1851 int sock_getsockopt(struct socket *sock, int level, int op,
1852 		    char __user *optval, int __user *optlen);
1853 int sock_gettstamp(struct socket *sock, void __user *userstamp,
1854 		   bool timeval, bool time32);
1855 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1856 				     unsigned long data_len, int noblock,
1857 				     int *errcode, int max_page_order);
1858 
sock_alloc_send_skb(struct sock * sk,unsigned long size,int noblock,int * errcode)1859 static inline struct sk_buff *sock_alloc_send_skb(struct sock *sk,
1860 						  unsigned long size,
1861 						  int noblock, int *errcode)
1862 {
1863 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1864 }
1865 
1866 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1867 void sock_kfree_s(struct sock *sk, void *mem, int size);
1868 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1869 void sk_send_sigurg(struct sock *sk);
1870 
1871 struct sockcm_cookie {
1872 	u64 transmit_time;
1873 	u32 mark;
1874 	u16 tsflags;
1875 };
1876 
sockcm_init(struct sockcm_cookie * sockc,const struct sock * sk)1877 static inline void sockcm_init(struct sockcm_cookie *sockc,
1878 			       const struct sock *sk)
1879 {
1880 	*sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
1881 }
1882 
1883 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1884 		     struct sockcm_cookie *sockc);
1885 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1886 		   struct sockcm_cookie *sockc);
1887 
1888 /*
1889  * Functions to fill in entries in struct proto_ops when a protocol
1890  * does not implement a particular function.
1891  */
1892 int sock_no_bind(struct socket *, struct sockaddr *, int);
1893 int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1894 int sock_no_socketpair(struct socket *, struct socket *);
1895 int sock_no_accept(struct socket *, struct socket *, int, bool);
1896 int sock_no_getname(struct socket *, struct sockaddr *, int);
1897 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1898 int sock_no_listen(struct socket *, int);
1899 int sock_no_shutdown(struct socket *, int);
1900 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1901 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1902 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1903 int sock_no_mmap(struct file *file, struct socket *sock,
1904 		 struct vm_area_struct *vma);
1905 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1906 			 size_t size, int flags);
1907 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1908 				int offset, size_t size, int flags);
1909 
1910 /*
1911  * Functions to fill in entries in struct proto_ops when a protocol
1912  * uses the inet style.
1913  */
1914 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1915 				  char __user *optval, int __user *optlen);
1916 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1917 			int flags);
1918 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1919 			   sockptr_t optval, unsigned int optlen);
1920 
1921 void sk_common_release(struct sock *sk);
1922 
1923 /*
1924  *	Default socket callbacks and setup code
1925  */
1926 
1927 /* Initialise core socket variables */
1928 void sock_init_data(struct socket *sock, struct sock *sk);
1929 
1930 /*
1931  * Socket reference counting postulates.
1932  *
1933  * * Each user of socket SHOULD hold a reference count.
1934  * * Each access point to socket (an hash table bucket, reference from a list,
1935  *   running timer, skb in flight MUST hold a reference count.
1936  * * When reference count hits 0, it means it will never increase back.
1937  * * When reference count hits 0, it means that no references from
1938  *   outside exist to this socket and current process on current CPU
1939  *   is last user and may/should destroy this socket.
1940  * * sk_free is called from any context: process, BH, IRQ. When
1941  *   it is called, socket has no references from outside -> sk_free
1942  *   may release descendant resources allocated by the socket, but
1943  *   to the time when it is called, socket is NOT referenced by any
1944  *   hash tables, lists etc.
1945  * * Packets, delivered from outside (from network or from another process)
1946  *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1947  *   when they sit in queue. Otherwise, packets will leak to hole, when
1948  *   socket is looked up by one cpu and unhasing is made by another CPU.
1949  *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1950  *   (leak to backlog). Packet socket does all the processing inside
1951  *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1952  *   use separate SMP lock, so that they are prone too.
1953  */
1954 
1955 /* Ungrab socket and destroy it, if it was the last reference. */
sock_put(struct sock * sk)1956 static inline void sock_put(struct sock *sk)
1957 {
1958 	if (refcount_dec_and_test(&sk->sk_refcnt))
1959 		sk_free(sk);
1960 }
1961 /* Generic version of sock_put(), dealing with all sockets
1962  * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1963  */
1964 void sock_gen_put(struct sock *sk);
1965 
1966 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1967 		     unsigned int trim_cap, bool refcounted);
sk_receive_skb(struct sock * sk,struct sk_buff * skb,const int nested)1968 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1969 				 const int nested)
1970 {
1971 	return __sk_receive_skb(sk, skb, nested, 1, true);
1972 }
1973 
sk_tx_queue_set(struct sock * sk,int tx_queue)1974 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1975 {
1976 	/* sk_tx_queue_mapping accept only upto a 16-bit value */
1977 	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1978 		return;
1979 	sk->sk_tx_queue_mapping = tx_queue;
1980 }
1981 
1982 #define NO_QUEUE_MAPPING	USHRT_MAX
1983 
sk_tx_queue_clear(struct sock * sk)1984 static inline void sk_tx_queue_clear(struct sock *sk)
1985 {
1986 	sk->sk_tx_queue_mapping = NO_QUEUE_MAPPING;
1987 }
1988 
sk_tx_queue_get(const struct sock * sk)1989 static inline int sk_tx_queue_get(const struct sock *sk)
1990 {
1991 	if (sk && sk->sk_tx_queue_mapping != NO_QUEUE_MAPPING)
1992 		return sk->sk_tx_queue_mapping;
1993 
1994 	return -1;
1995 }
1996 
__sk_rx_queue_set(struct sock * sk,const struct sk_buff * skb,bool force_set)1997 static inline void __sk_rx_queue_set(struct sock *sk,
1998 				     const struct sk_buff *skb,
1999 				     bool force_set)
2000 {
2001 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2002 	if (skb_rx_queue_recorded(skb)) {
2003 		u16 rx_queue = skb_get_rx_queue(skb);
2004 
2005 		if (force_set ||
2006 		    unlikely(READ_ONCE(sk->sk_rx_queue_mapping) != rx_queue))
2007 			WRITE_ONCE(sk->sk_rx_queue_mapping, rx_queue);
2008 	}
2009 #endif
2010 }
2011 
sk_rx_queue_set(struct sock * sk,const struct sk_buff * skb)2012 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
2013 {
2014 	__sk_rx_queue_set(sk, skb, true);
2015 }
2016 
sk_rx_queue_update(struct sock * sk,const struct sk_buff * skb)2017 static inline void sk_rx_queue_update(struct sock *sk, const struct sk_buff *skb)
2018 {
2019 	__sk_rx_queue_set(sk, skb, false);
2020 }
2021 
sk_rx_queue_clear(struct sock * sk)2022 static inline void sk_rx_queue_clear(struct sock *sk)
2023 {
2024 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2025 	WRITE_ONCE(sk->sk_rx_queue_mapping, NO_QUEUE_MAPPING);
2026 #endif
2027 }
2028 
sk_rx_queue_get(const struct sock * sk)2029 static inline int sk_rx_queue_get(const struct sock *sk)
2030 {
2031 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
2032 	if (sk) {
2033 		int res = READ_ONCE(sk->sk_rx_queue_mapping);
2034 
2035 		if (res != NO_QUEUE_MAPPING)
2036 			return res;
2037 	}
2038 #endif
2039 
2040 	return -1;
2041 }
2042 
sk_set_socket(struct sock * sk,struct socket * sock)2043 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
2044 {
2045 	sk->sk_socket = sock;
2046 }
2047 
sk_sleep(struct sock * sk)2048 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2049 {
2050 	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2051 	return &rcu_dereference_raw(sk->sk_wq)->wait;
2052 }
2053 /* Detach socket from process context.
2054  * Announce socket dead, detach it from wait queue and inode.
2055  * Note that parent inode held reference count on this struct sock,
2056  * we do not release it in this function, because protocol
2057  * probably wants some additional cleanups or even continuing
2058  * to work with this socket (TCP).
2059  */
sock_orphan(struct sock * sk)2060 static inline void sock_orphan(struct sock *sk)
2061 {
2062 	write_lock_bh(&sk->sk_callback_lock);
2063 	sock_set_flag(sk, SOCK_DEAD);
2064 	sk_set_socket(sk, NULL);
2065 	sk->sk_wq  = NULL;
2066 	write_unlock_bh(&sk->sk_callback_lock);
2067 }
2068 
sock_graft(struct sock * sk,struct socket * parent)2069 static inline void sock_graft(struct sock *sk, struct socket *parent)
2070 {
2071 	WARN_ON(parent->sk);
2072 	write_lock_bh(&sk->sk_callback_lock);
2073 	rcu_assign_pointer(sk->sk_wq, &parent->wq);
2074 	parent->sk = sk;
2075 	sk_set_socket(sk, parent);
2076 	sk->sk_uid = SOCK_INODE(parent)->i_uid;
2077 	security_sock_graft(sk, parent);
2078 	write_unlock_bh(&sk->sk_callback_lock);
2079 }
2080 
2081 kuid_t sock_i_uid(struct sock *sk);
2082 unsigned long sock_i_ino(struct sock *sk);
2083 
sock_net_uid(const struct net * net,const struct sock * sk)2084 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2085 {
2086 	return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
2087 }
2088 
net_tx_rndhash(void)2089 static inline u32 net_tx_rndhash(void)
2090 {
2091 	u32 v = prandom_u32();
2092 
2093 	return v ?: 1;
2094 }
2095 
sk_set_txhash(struct sock * sk)2096 static inline void sk_set_txhash(struct sock *sk)
2097 {
2098 	/* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2099 	WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2100 }
2101 
sk_rethink_txhash(struct sock * sk)2102 static inline bool sk_rethink_txhash(struct sock *sk)
2103 {
2104 	if (sk->sk_txhash && sk->sk_txrehash == SOCK_TXREHASH_ENABLED) {
2105 		sk_set_txhash(sk);
2106 		return true;
2107 	}
2108 	return false;
2109 }
2110 
2111 static inline struct dst_entry *
__sk_dst_get(struct sock * sk)2112 __sk_dst_get(struct sock *sk)
2113 {
2114 	return rcu_dereference_check(sk->sk_dst_cache,
2115 				     lockdep_sock_is_held(sk));
2116 }
2117 
2118 static inline struct dst_entry *
sk_dst_get(struct sock * sk)2119 sk_dst_get(struct sock *sk)
2120 {
2121 	struct dst_entry *dst;
2122 
2123 	rcu_read_lock();
2124 	dst = rcu_dereference(sk->sk_dst_cache);
2125 	if (dst && !atomic_inc_not_zero(&dst->__refcnt))
2126 		dst = NULL;
2127 	rcu_read_unlock();
2128 	return dst;
2129 }
2130 
__dst_negative_advice(struct sock * sk)2131 static inline void __dst_negative_advice(struct sock *sk)
2132 {
2133 	struct dst_entry *ndst, *dst = __sk_dst_get(sk);
2134 
2135 	if (dst && dst->ops->negative_advice) {
2136 		ndst = dst->ops->negative_advice(dst);
2137 
2138 		if (ndst != dst) {
2139 			rcu_assign_pointer(sk->sk_dst_cache, ndst);
2140 			sk_tx_queue_clear(sk);
2141 			sk->sk_dst_pending_confirm = 0;
2142 		}
2143 	}
2144 }
2145 
dst_negative_advice(struct sock * sk)2146 static inline void dst_negative_advice(struct sock *sk)
2147 {
2148 	sk_rethink_txhash(sk);
2149 	__dst_negative_advice(sk);
2150 }
2151 
2152 static inline void
__sk_dst_set(struct sock * sk,struct dst_entry * dst)2153 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
2154 {
2155 	struct dst_entry *old_dst;
2156 
2157 	sk_tx_queue_clear(sk);
2158 	sk->sk_dst_pending_confirm = 0;
2159 	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2160 					    lockdep_sock_is_held(sk));
2161 	rcu_assign_pointer(sk->sk_dst_cache, dst);
2162 	dst_release(old_dst);
2163 }
2164 
2165 static inline void
sk_dst_set(struct sock * sk,struct dst_entry * dst)2166 sk_dst_set(struct sock *sk, struct dst_entry *dst)
2167 {
2168 	struct dst_entry *old_dst;
2169 
2170 	sk_tx_queue_clear(sk);
2171 	sk->sk_dst_pending_confirm = 0;
2172 	old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2173 	dst_release(old_dst);
2174 }
2175 
2176 static inline void
__sk_dst_reset(struct sock * sk)2177 __sk_dst_reset(struct sock *sk)
2178 {
2179 	__sk_dst_set(sk, NULL);
2180 }
2181 
2182 static inline void
sk_dst_reset(struct sock * sk)2183 sk_dst_reset(struct sock *sk)
2184 {
2185 	sk_dst_set(sk, NULL);
2186 }
2187 
2188 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2189 
2190 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2191 
sk_dst_confirm(struct sock * sk)2192 static inline void sk_dst_confirm(struct sock *sk)
2193 {
2194 	if (!READ_ONCE(sk->sk_dst_pending_confirm))
2195 		WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2196 }
2197 
sock_confirm_neigh(struct sk_buff * skb,struct neighbour * n)2198 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2199 {
2200 	if (skb_get_dst_pending_confirm(skb)) {
2201 		struct sock *sk = skb->sk;
2202 
2203 		if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2204 			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2205 		neigh_confirm(n);
2206 	}
2207 }
2208 
2209 bool sk_mc_loop(struct sock *sk);
2210 
sk_can_gso(const struct sock * sk)2211 static inline bool sk_can_gso(const struct sock *sk)
2212 {
2213 	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2214 }
2215 
2216 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2217 
sk_gso_disable(struct sock * sk)2218 static inline void sk_gso_disable(struct sock *sk)
2219 {
2220 	sk->sk_gso_disabled = 1;
2221 	sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2222 }
2223 
skb_do_copy_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,char * to,int copy,int offset)2224 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2225 					   struct iov_iter *from, char *to,
2226 					   int copy, int offset)
2227 {
2228 	if (skb->ip_summed == CHECKSUM_NONE) {
2229 		__wsum csum = 0;
2230 		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2231 			return -EFAULT;
2232 		skb->csum = csum_block_add(skb->csum, csum, offset);
2233 	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2234 		if (!copy_from_iter_full_nocache(to, copy, from))
2235 			return -EFAULT;
2236 	} else if (!copy_from_iter_full(to, copy, from))
2237 		return -EFAULT;
2238 
2239 	return 0;
2240 }
2241 
skb_add_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,int copy)2242 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2243 				       struct iov_iter *from, int copy)
2244 {
2245 	int err, offset = skb->len;
2246 
2247 	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2248 				       copy, offset);
2249 	if (err)
2250 		__skb_trim(skb, offset);
2251 
2252 	return err;
2253 }
2254 
skb_copy_to_page_nocache(struct sock * sk,struct iov_iter * from,struct sk_buff * skb,struct page * page,int off,int copy)2255 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2256 					   struct sk_buff *skb,
2257 					   struct page *page,
2258 					   int off, int copy)
2259 {
2260 	int err;
2261 
2262 	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2263 				       copy, skb->len);
2264 	if (err)
2265 		return err;
2266 
2267 	skb->len	     += copy;
2268 	skb->data_len	     += copy;
2269 	skb->truesize	     += copy;
2270 	sk_wmem_queued_add(sk, copy);
2271 	sk_mem_charge(sk, copy);
2272 	return 0;
2273 }
2274 
2275 /**
2276  * sk_wmem_alloc_get - returns write allocations
2277  * @sk: socket
2278  *
2279  * Return: sk_wmem_alloc minus initial offset of one
2280  */
sk_wmem_alloc_get(const struct sock * sk)2281 static inline int sk_wmem_alloc_get(const struct sock *sk)
2282 {
2283 	return refcount_read(&sk->sk_wmem_alloc) - 1;
2284 }
2285 
2286 /**
2287  * sk_rmem_alloc_get - returns read allocations
2288  * @sk: socket
2289  *
2290  * Return: sk_rmem_alloc
2291  */
sk_rmem_alloc_get(const struct sock * sk)2292 static inline int sk_rmem_alloc_get(const struct sock *sk)
2293 {
2294 	return atomic_read(&sk->sk_rmem_alloc);
2295 }
2296 
2297 /**
2298  * sk_has_allocations - check if allocations are outstanding
2299  * @sk: socket
2300  *
2301  * Return: true if socket has write or read allocations
2302  */
sk_has_allocations(const struct sock * sk)2303 static inline bool sk_has_allocations(const struct sock *sk)
2304 {
2305 	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2306 }
2307 
2308 /**
2309  * skwq_has_sleeper - check if there are any waiting processes
2310  * @wq: struct socket_wq
2311  *
2312  * Return: true if socket_wq has waiting processes
2313  *
2314  * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2315  * barrier call. They were added due to the race found within the tcp code.
2316  *
2317  * Consider following tcp code paths::
2318  *
2319  *   CPU1                CPU2
2320  *   sys_select          receive packet
2321  *   ...                 ...
2322  *   __add_wait_queue    update tp->rcv_nxt
2323  *   ...                 ...
2324  *   tp->rcv_nxt check   sock_def_readable
2325  *   ...                 {
2326  *   schedule               rcu_read_lock();
2327  *                          wq = rcu_dereference(sk->sk_wq);
2328  *                          if (wq && waitqueue_active(&wq->wait))
2329  *                              wake_up_interruptible(&wq->wait)
2330  *                          ...
2331  *                       }
2332  *
2333  * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2334  * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
2335  * could then endup calling schedule and sleep forever if there are no more
2336  * data on the socket.
2337  *
2338  */
skwq_has_sleeper(struct socket_wq * wq)2339 static inline bool skwq_has_sleeper(struct socket_wq *wq)
2340 {
2341 	return wq && wq_has_sleeper(&wq->wait);
2342 }
2343 
2344 /**
2345  * sock_poll_wait - place memory barrier behind the poll_wait call.
2346  * @filp:           file
2347  * @sock:           socket to wait on
2348  * @p:              poll_table
2349  *
2350  * See the comments in the wq_has_sleeper function.
2351  */
sock_poll_wait(struct file * filp,struct socket * sock,poll_table * p)2352 static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2353 				  poll_table *p)
2354 {
2355 	if (!poll_does_not_wait(p)) {
2356 		poll_wait(filp, &sock->wq.wait, p);
2357 		/* We need to be sure we are in sync with the
2358 		 * socket flags modification.
2359 		 *
2360 		 * This memory barrier is paired in the wq_has_sleeper.
2361 		 */
2362 		smp_mb();
2363 	}
2364 }
2365 
skb_set_hash_from_sk(struct sk_buff * skb,struct sock * sk)2366 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2367 {
2368 	/* This pairs with WRITE_ONCE() in sk_set_txhash() */
2369 	u32 txhash = READ_ONCE(sk->sk_txhash);
2370 
2371 	if (txhash) {
2372 		skb->l4_hash = 1;
2373 		skb->hash = txhash;
2374 	}
2375 }
2376 
2377 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2378 
2379 /*
2380  *	Queue a received datagram if it will fit. Stream and sequenced
2381  *	protocols can't normally use this as they need to fit buffers in
2382  *	and play with them.
2383  *
2384  *	Inlined as it's very short and called for pretty much every
2385  *	packet ever received.
2386  */
skb_set_owner_r(struct sk_buff * skb,struct sock * sk)2387 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2388 {
2389 	skb_orphan(skb);
2390 	skb->sk = sk;
2391 	skb->destructor = sock_rfree;
2392 	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2393 	sk_mem_charge(sk, skb->truesize);
2394 }
2395 
skb_set_owner_sk_safe(struct sk_buff * skb,struct sock * sk)2396 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2397 {
2398 	if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2399 		skb_orphan(skb);
2400 		skb->destructor = sock_efree;
2401 		skb->sk = sk;
2402 		return true;
2403 	}
2404 	return false;
2405 }
2406 
skb_prepare_for_gro(struct sk_buff * skb)2407 static inline void skb_prepare_for_gro(struct sk_buff *skb)
2408 {
2409 	if (skb->destructor != sock_wfree) {
2410 		skb_orphan(skb);
2411 		return;
2412 	}
2413 	skb->slow_gro = 1;
2414 }
2415 
2416 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2417 		    unsigned long expires);
2418 
2419 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2420 
2421 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2422 
2423 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2424 			struct sk_buff *skb, unsigned int flags,
2425 			void (*destructor)(struct sock *sk,
2426 					   struct sk_buff *skb));
2427 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2428 
2429 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
2430 			      enum skb_drop_reason *reason);
2431 
sock_queue_rcv_skb(struct sock * sk,struct sk_buff * skb)2432 static inline int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2433 {
2434 	return sock_queue_rcv_skb_reason(sk, skb, NULL);
2435 }
2436 
2437 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2438 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2439 
2440 /*
2441  *	Recover an error report and clear atomically
2442  */
2443 
sock_error(struct sock * sk)2444 static inline int sock_error(struct sock *sk)
2445 {
2446 	int err;
2447 
2448 	/* Avoid an atomic operation for the common case.
2449 	 * This is racy since another cpu/thread can change sk_err under us.
2450 	 */
2451 	if (likely(data_race(!sk->sk_err)))
2452 		return 0;
2453 
2454 	err = xchg(&sk->sk_err, 0);
2455 	return -err;
2456 }
2457 
2458 void sk_error_report(struct sock *sk);
2459 
sock_wspace(struct sock * sk)2460 static inline unsigned long sock_wspace(struct sock *sk)
2461 {
2462 	int amt = 0;
2463 
2464 	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2465 		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2466 		if (amt < 0)
2467 			amt = 0;
2468 	}
2469 	return amt;
2470 }
2471 
2472 /* Note:
2473  *  We use sk->sk_wq_raw, from contexts knowing this
2474  *  pointer is not NULL and cannot disappear/change.
2475  */
sk_set_bit(int nr,struct sock * sk)2476 static inline void sk_set_bit(int nr, struct sock *sk)
2477 {
2478 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2479 	    !sock_flag(sk, SOCK_FASYNC))
2480 		return;
2481 
2482 	set_bit(nr, &sk->sk_wq_raw->flags);
2483 }
2484 
sk_clear_bit(int nr,struct sock * sk)2485 static inline void sk_clear_bit(int nr, struct sock *sk)
2486 {
2487 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2488 	    !sock_flag(sk, SOCK_FASYNC))
2489 		return;
2490 
2491 	clear_bit(nr, &sk->sk_wq_raw->flags);
2492 }
2493 
sk_wake_async(const struct sock * sk,int how,int band)2494 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2495 {
2496 	if (sock_flag(sk, SOCK_FASYNC)) {
2497 		rcu_read_lock();
2498 		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2499 		rcu_read_unlock();
2500 	}
2501 }
2502 
2503 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2504  * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2505  * Note: for send buffers, TCP works better if we can build two skbs at
2506  * minimum.
2507  */
2508 #define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2509 
2510 #define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2511 #define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2512 
sk_stream_moderate_sndbuf(struct sock * sk)2513 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2514 {
2515 	u32 val;
2516 
2517 	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2518 		return;
2519 
2520 	val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2521 	val = max_t(u32, val, sk_unused_reserved_mem(sk));
2522 
2523 	WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2524 }
2525 
2526 /**
2527  * sk_page_frag - return an appropriate page_frag
2528  * @sk: socket
2529  *
2530  * Use the per task page_frag instead of the per socket one for
2531  * optimization when we know that we're in process context and own
2532  * everything that's associated with %current.
2533  *
2534  * Both direct reclaim and page faults can nest inside other
2535  * socket operations and end up recursing into sk_page_frag()
2536  * while it's already in use: explicitly avoid task page_frag
2537  * usage if the caller is potentially doing any of them.
2538  * This assumes that page fault handlers use the GFP_NOFS flags.
2539  *
2540  * Return: a per task page_frag if context allows that,
2541  * otherwise a per socket one.
2542  */
sk_page_frag(struct sock * sk)2543 static inline struct page_frag *sk_page_frag(struct sock *sk)
2544 {
2545 	if ((sk->sk_allocation & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC | __GFP_FS)) ==
2546 	    (__GFP_DIRECT_RECLAIM | __GFP_FS))
2547 		return &current->task_frag;
2548 
2549 	return &sk->sk_frag;
2550 }
2551 
2552 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2553 
2554 /*
2555  *	Default write policy as shown to user space via poll/select/SIGIO
2556  */
sock_writeable(const struct sock * sk)2557 static inline bool sock_writeable(const struct sock *sk)
2558 {
2559 	return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2560 }
2561 
gfp_any(void)2562 static inline gfp_t gfp_any(void)
2563 {
2564 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2565 }
2566 
gfp_memcg_charge(void)2567 static inline gfp_t gfp_memcg_charge(void)
2568 {
2569 	return in_softirq() ? GFP_NOWAIT : GFP_KERNEL;
2570 }
2571 
sock_rcvtimeo(const struct sock * sk,bool noblock)2572 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2573 {
2574 	return noblock ? 0 : sk->sk_rcvtimeo;
2575 }
2576 
sock_sndtimeo(const struct sock * sk,bool noblock)2577 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2578 {
2579 	return noblock ? 0 : sk->sk_sndtimeo;
2580 }
2581 
sock_rcvlowat(const struct sock * sk,int waitall,int len)2582 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2583 {
2584 	int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2585 
2586 	return v ?: 1;
2587 }
2588 
2589 /* Alas, with timeout socket operations are not restartable.
2590  * Compare this to poll().
2591  */
sock_intr_errno(long timeo)2592 static inline int sock_intr_errno(long timeo)
2593 {
2594 	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2595 }
2596 
2597 struct sock_skb_cb {
2598 	u32 dropcount;
2599 };
2600 
2601 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2602  * using skb->cb[] would keep using it directly and utilize its
2603  * alignement guarantee.
2604  */
2605 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2606 			    sizeof(struct sock_skb_cb)))
2607 
2608 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2609 			    SOCK_SKB_CB_OFFSET))
2610 
2611 #define sock_skb_cb_check_size(size) \
2612 	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2613 
2614 static inline void
sock_skb_set_dropcount(const struct sock * sk,struct sk_buff * skb)2615 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2616 {
2617 	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2618 						atomic_read(&sk->sk_drops) : 0;
2619 }
2620 
sk_drops_add(struct sock * sk,const struct sk_buff * skb)2621 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2622 {
2623 	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2624 
2625 	atomic_add(segs, &sk->sk_drops);
2626 }
2627 
sock_read_timestamp(struct sock * sk)2628 static inline ktime_t sock_read_timestamp(struct sock *sk)
2629 {
2630 #if BITS_PER_LONG==32
2631 	unsigned int seq;
2632 	ktime_t kt;
2633 
2634 	do {
2635 		seq = read_seqbegin(&sk->sk_stamp_seq);
2636 		kt = sk->sk_stamp;
2637 	} while (read_seqretry(&sk->sk_stamp_seq, seq));
2638 
2639 	return kt;
2640 #else
2641 	return READ_ONCE(sk->sk_stamp);
2642 #endif
2643 }
2644 
sock_write_timestamp(struct sock * sk,ktime_t kt)2645 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2646 {
2647 #if BITS_PER_LONG==32
2648 	write_seqlock(&sk->sk_stamp_seq);
2649 	sk->sk_stamp = kt;
2650 	write_sequnlock(&sk->sk_stamp_seq);
2651 #else
2652 	WRITE_ONCE(sk->sk_stamp, kt);
2653 #endif
2654 }
2655 
2656 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2657 			   struct sk_buff *skb);
2658 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2659 			     struct sk_buff *skb);
2660 
2661 static inline void
sock_recv_timestamp(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2662 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2663 {
2664 	ktime_t kt = skb->tstamp;
2665 	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2666 
2667 	/*
2668 	 * generate control messages if
2669 	 * - receive time stamping in software requested
2670 	 * - software time stamp available and wanted
2671 	 * - hardware time stamps available and wanted
2672 	 */
2673 	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2674 	    (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2675 	    (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2676 	    (hwtstamps->hwtstamp &&
2677 	     (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2678 		__sock_recv_timestamp(msg, sk, skb);
2679 	else
2680 		sock_write_timestamp(sk, kt);
2681 
2682 	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2683 		__sock_recv_wifi_status(msg, sk, skb);
2684 }
2685 
2686 void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2687 		       struct sk_buff *skb);
2688 
2689 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
sock_recv_cmsgs(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2690 static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2691 				   struct sk_buff *skb)
2692 {
2693 #define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL)			| \
2694 			   (1UL << SOCK_RCVTSTAMP)			| \
2695 			   (1UL << SOCK_RCVMARK))
2696 #define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
2697 			   SOF_TIMESTAMPING_RAW_HARDWARE)
2698 
2699 	if (sk->sk_flags & FLAGS_RECV_CMSGS || sk->sk_tsflags & TSFLAGS_ANY)
2700 		__sock_recv_cmsgs(msg, sk, skb);
2701 	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2702 		sock_write_timestamp(sk, skb->tstamp);
2703 	else if (unlikely(sk->sk_stamp == SK_DEFAULT_STAMP))
2704 		sock_write_timestamp(sk, 0);
2705 }
2706 
2707 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2708 
2709 /**
2710  * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2711  * @sk:		socket sending this packet
2712  * @tsflags:	timestamping flags to use
2713  * @tx_flags:	completed with instructions for time stamping
2714  * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
2715  *
2716  * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2717  */
_sock_tx_timestamp(struct sock * sk,__u16 tsflags,__u8 * tx_flags,__u32 * tskey)2718 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2719 				      __u8 *tx_flags, __u32 *tskey)
2720 {
2721 	if (unlikely(tsflags)) {
2722 		__sock_tx_timestamp(tsflags, tx_flags);
2723 		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2724 		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2725 			*tskey = atomic_inc_return(&sk->sk_tskey) - 1;
2726 	}
2727 	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2728 		*tx_flags |= SKBTX_WIFI_STATUS;
2729 }
2730 
sock_tx_timestamp(struct sock * sk,__u16 tsflags,__u8 * tx_flags)2731 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2732 				     __u8 *tx_flags)
2733 {
2734 	_sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2735 }
2736 
skb_setup_tx_timestamp(struct sk_buff * skb,__u16 tsflags)2737 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2738 {
2739 	_sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2740 			   &skb_shinfo(skb)->tskey);
2741 }
2742 
sk_is_tcp(const struct sock * sk)2743 static inline bool sk_is_tcp(const struct sock *sk)
2744 {
2745 	return sk->sk_type == SOCK_STREAM && sk->sk_protocol == IPPROTO_TCP;
2746 }
2747 
2748 /**
2749  * sk_eat_skb - Release a skb if it is no longer needed
2750  * @sk: socket to eat this skb from
2751  * @skb: socket buffer to eat
2752  *
2753  * This routine must be called with interrupts disabled or with the socket
2754  * locked so that the sk_buff queue operation is ok.
2755 */
sk_eat_skb(struct sock * sk,struct sk_buff * skb)2756 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2757 {
2758 	__skb_unlink(skb, &sk->sk_receive_queue);
2759 	__kfree_skb(skb);
2760 }
2761 
2762 static inline bool
skb_sk_is_prefetched(struct sk_buff * skb)2763 skb_sk_is_prefetched(struct sk_buff *skb)
2764 {
2765 #ifdef CONFIG_INET
2766 	return skb->destructor == sock_pfree;
2767 #else
2768 	return false;
2769 #endif /* CONFIG_INET */
2770 }
2771 
2772 /* This helper checks if a socket is a full socket,
2773  * ie _not_ a timewait or request socket.
2774  */
sk_fullsock(const struct sock * sk)2775 static inline bool sk_fullsock(const struct sock *sk)
2776 {
2777 	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2778 }
2779 
2780 static inline bool
sk_is_refcounted(struct sock * sk)2781 sk_is_refcounted(struct sock *sk)
2782 {
2783 	/* Only full sockets have sk->sk_flags. */
2784 	return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2785 }
2786 
2787 /**
2788  * skb_steal_sock - steal a socket from an sk_buff
2789  * @skb: sk_buff to steal the socket from
2790  * @refcounted: is set to true if the socket is reference-counted
2791  */
2792 static inline struct sock *
skb_steal_sock(struct sk_buff * skb,bool * refcounted)2793 skb_steal_sock(struct sk_buff *skb, bool *refcounted)
2794 {
2795 	if (skb->sk) {
2796 		struct sock *sk = skb->sk;
2797 
2798 		*refcounted = true;
2799 		if (skb_sk_is_prefetched(skb))
2800 			*refcounted = sk_is_refcounted(sk);
2801 		skb->destructor = NULL;
2802 		skb->sk = NULL;
2803 		return sk;
2804 	}
2805 	*refcounted = false;
2806 	return NULL;
2807 }
2808 
2809 /* Checks if this SKB belongs to an HW offloaded socket
2810  * and whether any SW fallbacks are required based on dev.
2811  * Check decrypted mark in case skb_orphan() cleared socket.
2812  */
sk_validate_xmit_skb(struct sk_buff * skb,struct net_device * dev)2813 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2814 						   struct net_device *dev)
2815 {
2816 #ifdef CONFIG_SOCK_VALIDATE_XMIT
2817 	struct sock *sk = skb->sk;
2818 
2819 	if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2820 		skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2821 #ifdef CONFIG_TLS_DEVICE
2822 	} else if (unlikely(skb->decrypted)) {
2823 		pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2824 		kfree_skb(skb);
2825 		skb = NULL;
2826 #endif
2827 	}
2828 #endif
2829 
2830 	return skb;
2831 }
2832 
2833 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2834  * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2835  */
sk_listener(const struct sock * sk)2836 static inline bool sk_listener(const struct sock *sk)
2837 {
2838 	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2839 }
2840 
2841 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2842 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2843 		       int type);
2844 
2845 bool sk_ns_capable(const struct sock *sk,
2846 		   struct user_namespace *user_ns, int cap);
2847 bool sk_capable(const struct sock *sk, int cap);
2848 bool sk_net_capable(const struct sock *sk, int cap);
2849 
2850 void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2851 
2852 /* Take into consideration the size of the struct sk_buff overhead in the
2853  * determination of these values, since that is non-constant across
2854  * platforms.  This makes socket queueing behavior and performance
2855  * not depend upon such differences.
2856  */
2857 #define _SK_MEM_PACKETS		256
2858 #define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
2859 #define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2860 #define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2861 
2862 extern __u32 sysctl_wmem_max;
2863 extern __u32 sysctl_rmem_max;
2864 
2865 extern int sysctl_tstamp_allow_data;
2866 extern int sysctl_optmem_max;
2867 
2868 extern __u32 sysctl_wmem_default;
2869 extern __u32 sysctl_rmem_default;
2870 
2871 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2872 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2873 
sk_get_wmem0(const struct sock * sk,const struct proto * proto)2874 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2875 {
2876 	/* Does this proto have per netns sysctl_wmem ? */
2877 	if (proto->sysctl_wmem_offset)
2878 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2879 
2880 	return READ_ONCE(*proto->sysctl_wmem);
2881 }
2882 
sk_get_rmem0(const struct sock * sk,const struct proto * proto)2883 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2884 {
2885 	/* Does this proto have per netns sysctl_rmem ? */
2886 	if (proto->sysctl_rmem_offset)
2887 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2888 
2889 	return READ_ONCE(*proto->sysctl_rmem);
2890 }
2891 
2892 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2893  * Some wifi drivers need to tweak it to get more chunks.
2894  * They can use this helper from their ndo_start_xmit()
2895  */
sk_pacing_shift_update(struct sock * sk,int val)2896 static inline void sk_pacing_shift_update(struct sock *sk, int val)
2897 {
2898 	if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2899 		return;
2900 	WRITE_ONCE(sk->sk_pacing_shift, val);
2901 }
2902 
2903 /* if a socket is bound to a device, check that the given device
2904  * index is either the same or that the socket is bound to an L3
2905  * master device and the given device index is also enslaved to
2906  * that L3 master
2907  */
sk_dev_equal_l3scope(struct sock * sk,int dif)2908 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2909 {
2910 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
2911 	int mdif;
2912 
2913 	if (!bound_dev_if || bound_dev_if == dif)
2914 		return true;
2915 
2916 	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2917 	if (mdif && mdif == bound_dev_if)
2918 		return true;
2919 
2920 	return false;
2921 }
2922 
2923 void sock_def_readable(struct sock *sk);
2924 
2925 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2926 void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2927 int sock_set_timestamping(struct sock *sk, int optname,
2928 			  struct so_timestamping timestamping);
2929 
2930 void sock_enable_timestamps(struct sock *sk);
2931 void sock_no_linger(struct sock *sk);
2932 void sock_set_keepalive(struct sock *sk);
2933 void sock_set_priority(struct sock *sk, u32 priority);
2934 void sock_set_rcvbuf(struct sock *sk, int val);
2935 void sock_set_mark(struct sock *sk, u32 val);
2936 void sock_set_reuseaddr(struct sock *sk);
2937 void sock_set_reuseport(struct sock *sk);
2938 void sock_set_sndtimeo(struct sock *sk, s64 secs);
2939 
2940 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2941 
2942 int sock_get_timeout(long timeo, void *optval, bool old_timeval);
2943 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
2944 			   sockptr_t optval, int optlen, bool old_timeval);
2945 
sk_is_readable(struct sock * sk)2946 static inline bool sk_is_readable(struct sock *sk)
2947 {
2948 	if (sk->sk_prot->sock_is_readable)
2949 		return sk->sk_prot->sock_is_readable(sk);
2950 	return false;
2951 }
2952 #endif	/* _SOCK_H */
2953