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1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * INET		An implementation of the TCP/IP protocol suite for the LINUX
4  *		operating system.  INET is implemented using the  BSD Socket
5  *		interface as the means of communication with the user level.
6  *
7  *		Definitions for the AF_INET socket handler.
8  *
9  * Version:	@(#)sock.h	1.0.4	05/13/93
10  *
11  * Authors:	Ross Biro
12  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
13  *		Corey Minyard <wf-rch!minyard@relay.EU.net>
14  *		Florian La Roche <flla@stud.uni-sb.de>
15  *
16  * Fixes:
17  *		Alan Cox	:	Volatiles in skbuff pointers. See
18  *					skbuff comments. May be overdone,
19  *					better to prove they can be removed
20  *					than the reverse.
21  *		Alan Cox	:	Added a zapped field for tcp to note
22  *					a socket is reset and must stay shut up
23  *		Alan Cox	:	New fields for options
24  *	Pauline Middelink	:	identd support
25  *		Alan Cox	:	Eliminate low level recv/recvfrom
26  *		David S. Miller	:	New socket lookup architecture.
27  *              Steve Whitehouse:       Default routines for sock_ops
28  *              Arnaldo C. Melo :	removed net_pinfo, tp_pinfo and made
29  *              			protinfo be just a void pointer, as the
30  *              			protocol specific parts were moved to
31  *              			respective headers and ipv4/v6, etc now
32  *              			use private slabcaches for its socks
33  *              Pedro Hortas	:	New flags field for socket options
34  */
35 #ifndef _SOCK_H
36 #define _SOCK_H
37 
38 #include <linux/hardirq.h>
39 #include <linux/kernel.h>
40 #include <linux/list.h>
41 #include <linux/list_nulls.h>
42 #include <linux/timer.h>
43 #include <linux/cache.h>
44 #include <linux/bitops.h>
45 #include <linux/lockdep.h>
46 #include <linux/netdevice.h>
47 #include <linux/skbuff.h>	/* struct sk_buff */
48 #include <linux/mm.h>
49 #include <linux/security.h>
50 #include <linux/slab.h>
51 #include <linux/uaccess.h>
52 #include <linux/page_counter.h>
53 #include <linux/memcontrol.h>
54 #include <linux/static_key.h>
55 #include <linux/sched.h>
56 #include <linux/wait.h>
57 #include <linux/cgroup-defs.h>
58 #include <linux/rbtree.h>
59 #include <linux/filter.h>
60 #include <linux/rculist_nulls.h>
61 #include <linux/poll.h>
62 #include <linux/sockptr.h>
63 #include <linux/indirect_call_wrapper.h>
64 #include <linux/atomic.h>
65 #include <linux/refcount.h>
66 #include <net/dst.h>
67 #include <net/checksum.h>
68 #include <net/tcp_states.h>
69 #include <linux/net_tstamp.h>
70 #include <net/l3mdev.h>
71 #include <uapi/linux/socket.h>
72 #include <linux/android_vendor.h>
73 #include <linux/android_kabi.h>
74 
75 /*
76  * This structure really needs to be cleaned up.
77  * Most of it is for TCP, and not used by any of
78  * the other protocols.
79  */
80 
81 /* Define this to get the SOCK_DBG debugging facility. */
82 #define SOCK_DEBUGGING
83 #ifdef SOCK_DEBUGGING
84 #define SOCK_DEBUG(sk, msg...) do { if ((sk) && sock_flag((sk), SOCK_DBG)) \
85 					printk(KERN_DEBUG msg); } while (0)
86 #else
87 /* Validate arguments and do nothing */
88 static inline __printf(2, 3)
SOCK_DEBUG(const struct sock * sk,const char * msg,...)89 void SOCK_DEBUG(const struct sock *sk, const char *msg, ...)
90 {
91 }
92 #endif
93 
94 /* This is the per-socket lock.  The spinlock provides a synchronization
95  * between user contexts and software interrupt processing, whereas the
96  * mini-semaphore synchronizes multiple users amongst themselves.
97  */
98 typedef struct {
99 	spinlock_t		slock;
100 	int			owned;
101 	wait_queue_head_t	wq;
102 	/*
103 	 * We express the mutex-alike socket_lock semantics
104 	 * to the lock validator by explicitly managing
105 	 * the slock as a lock variant (in addition to
106 	 * the slock itself):
107 	 */
108 #ifdef CONFIG_DEBUG_LOCK_ALLOC
109 	struct lockdep_map dep_map;
110 #endif
111 } socket_lock_t;
112 
113 struct sock;
114 struct proto;
115 struct net;
116 
117 typedef __u32 __bitwise __portpair;
118 typedef __u64 __bitwise __addrpair;
119 
120 /**
121  *	struct sock_common - minimal network layer representation of sockets
122  *	@skc_daddr: Foreign IPv4 addr
123  *	@skc_rcv_saddr: Bound local IPv4 addr
124  *	@skc_addrpair: 8-byte-aligned __u64 union of @skc_daddr & @skc_rcv_saddr
125  *	@skc_hash: hash value used with various protocol lookup tables
126  *	@skc_u16hashes: two u16 hash values used by UDP lookup tables
127  *	@skc_dport: placeholder for inet_dport/tw_dport
128  *	@skc_num: placeholder for inet_num/tw_num
129  *	@skc_portpair: __u32 union of @skc_dport & @skc_num
130  *	@skc_family: network address family
131  *	@skc_state: Connection state
132  *	@skc_reuse: %SO_REUSEADDR setting
133  *	@skc_reuseport: %SO_REUSEPORT setting
134  *	@skc_ipv6only: socket is IPV6 only
135  *	@skc_net_refcnt: socket is using net ref counting
136  *	@skc_bound_dev_if: bound device index if != 0
137  *	@skc_bind_node: bind hash linkage for various protocol lookup tables
138  *	@skc_portaddr_node: second hash linkage for UDP/UDP-Lite protocol
139  *	@skc_prot: protocol handlers inside a network family
140  *	@skc_net: reference to the network namespace of this socket
141  *	@skc_v6_daddr: IPV6 destination address
142  *	@skc_v6_rcv_saddr: IPV6 source address
143  *	@skc_cookie: socket's cookie value
144  *	@skc_node: main hash linkage for various protocol lookup tables
145  *	@skc_nulls_node: main hash linkage for TCP/UDP/UDP-Lite protocol
146  *	@skc_tx_queue_mapping: tx queue number for this connection
147  *	@skc_rx_queue_mapping: rx queue number for this connection
148  *	@skc_flags: place holder for sk_flags
149  *		%SO_LINGER (l_onoff), %SO_BROADCAST, %SO_KEEPALIVE,
150  *		%SO_OOBINLINE settings, %SO_TIMESTAMPING settings
151  *	@skc_listener: connection request listener socket (aka rsk_listener)
152  *		[union with @skc_flags]
153  *	@skc_tw_dr: (aka tw_dr) ptr to &struct inet_timewait_death_row
154  *		[union with @skc_flags]
155  *	@skc_incoming_cpu: record/match cpu processing incoming packets
156  *	@skc_rcv_wnd: (aka rsk_rcv_wnd) TCP receive window size (possibly scaled)
157  *		[union with @skc_incoming_cpu]
158  *	@skc_tw_rcv_nxt: (aka tw_rcv_nxt) TCP window next expected seq number
159  *		[union with @skc_incoming_cpu]
160  *	@skc_refcnt: reference count
161  *
162  *	This is the minimal network layer representation of sockets, the header
163  *	for struct sock and struct inet_timewait_sock.
164  */
165 struct sock_common {
166 	union {
167 		__addrpair	skc_addrpair;
168 		struct {
169 			__be32	skc_daddr;
170 			__be32	skc_rcv_saddr;
171 		};
172 	};
173 	union  {
174 		unsigned int	skc_hash;
175 		__u16		skc_u16hashes[2];
176 	};
177 	/* skc_dport && skc_num must be grouped as well */
178 	union {
179 		__portpair	skc_portpair;
180 		struct {
181 			__be16	skc_dport;
182 			__u16	skc_num;
183 		};
184 	};
185 
186 	unsigned short		skc_family;
187 	volatile unsigned char	skc_state;
188 	unsigned char		skc_reuse:4;
189 	unsigned char		skc_reuseport:1;
190 	unsigned char		skc_ipv6only:1;
191 	unsigned char		skc_net_refcnt:1;
192 	int			skc_bound_dev_if;
193 	union {
194 		struct hlist_node	skc_bind_node;
195 		struct hlist_node	skc_portaddr_node;
196 	};
197 	struct proto		*skc_prot;
198 	possible_net_t		skc_net;
199 
200 #if IS_ENABLED(CONFIG_IPV6)
201 	struct in6_addr		skc_v6_daddr;
202 	struct in6_addr		skc_v6_rcv_saddr;
203 #endif
204 
205 	atomic64_t		skc_cookie;
206 
207 	/* following fields are padding to force
208 	 * offset(struct sock, sk_refcnt) == 128 on 64bit arches
209 	 * assuming IPV6 is enabled. We use this padding differently
210 	 * for different kind of 'sockets'
211 	 */
212 	union {
213 		unsigned long	skc_flags;
214 		struct sock	*skc_listener; /* request_sock */
215 		struct inet_timewait_death_row *skc_tw_dr; /* inet_timewait_sock */
216 	};
217 	/*
218 	 * fields between dontcopy_begin/dontcopy_end
219 	 * are not copied in sock_copy()
220 	 */
221 	/* private: */
222 	int			skc_dontcopy_begin[0];
223 	/* public: */
224 	union {
225 		struct hlist_node	skc_node;
226 		struct hlist_nulls_node skc_nulls_node;
227 	};
228 	unsigned short		skc_tx_queue_mapping;
229 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
230 	unsigned short		skc_rx_queue_mapping;
231 #endif
232 	union {
233 		int		skc_incoming_cpu;
234 		u32		skc_rcv_wnd;
235 		u32		skc_tw_rcv_nxt; /* struct tcp_timewait_sock  */
236 	};
237 
238 	refcount_t		skc_refcnt;
239 	/* private: */
240 	int                     skc_dontcopy_end[0];
241 	union {
242 		u32		skc_rxhash;
243 		u32		skc_window_clamp;
244 		u32		skc_tw_snd_nxt; /* struct tcp_timewait_sock */
245 	};
246 	/* public: */
247 };
248 
249 struct bpf_local_storage;
250 
251 /**
252   *	struct sock - network layer representation of sockets
253   *	@__sk_common: shared layout with inet_timewait_sock
254   *	@sk_shutdown: mask of %SEND_SHUTDOWN and/or %RCV_SHUTDOWN
255   *	@sk_userlocks: %SO_SNDBUF and %SO_RCVBUF settings
256   *	@sk_lock:	synchronizer
257   *	@sk_kern_sock: True if sock is using kernel lock classes
258   *	@sk_rcvbuf: size of receive buffer in bytes
259   *	@sk_wq: sock wait queue and async head
260   *	@sk_rx_dst: receive input route used by early demux
261   *	@sk_rx_dst_ifindex: ifindex for @sk_rx_dst
262   *	@sk_rx_dst_cookie: cookie for @sk_rx_dst
263   *	@sk_dst_cache: destination cache
264   *	@sk_dst_pending_confirm: need to confirm neighbour
265   *	@sk_policy: flow policy
266   *	@sk_rx_skb_cache: cache copy of recently accessed RX skb
267   *	@sk_receive_queue: incoming packets
268   *	@sk_wmem_alloc: transmit queue bytes committed
269   *	@sk_tsq_flags: TCP Small Queues flags
270   *	@sk_write_queue: Packet sending queue
271   *	@sk_omem_alloc: "o" is "option" or "other"
272   *	@sk_wmem_queued: persistent queue size
273   *	@sk_forward_alloc: space allocated forward
274   *	@sk_napi_id: id of the last napi context to receive data for sk
275   *	@sk_ll_usec: usecs to busypoll when there is no data
276   *	@sk_allocation: allocation mode
277   *	@sk_pacing_rate: Pacing rate (if supported by transport/packet scheduler)
278   *	@sk_pacing_status: Pacing status (requested, handled by sch_fq)
279   *	@sk_max_pacing_rate: Maximum pacing rate (%SO_MAX_PACING_RATE)
280   *	@sk_sndbuf: size of send buffer in bytes
281   *	@__sk_flags_offset: empty field used to determine location of bitfield
282   *	@sk_padding: unused element for alignment
283   *	@sk_no_check_tx: %SO_NO_CHECK setting, set checksum in TX packets
284   *	@sk_no_check_rx: allow zero checksum in RX packets
285   *	@sk_route_caps: route capabilities (e.g. %NETIF_F_TSO)
286   *	@sk_route_nocaps: forbidden route capabilities (e.g NETIF_F_GSO_MASK)
287   *	@sk_route_forced_caps: static, forced route capabilities
288   *		(set in tcp_init_sock())
289   *	@sk_gso_type: GSO type (e.g. %SKB_GSO_TCPV4)
290   *	@sk_gso_max_size: Maximum GSO segment size to build
291   *	@sk_gso_max_segs: Maximum number of GSO segments
292   *	@sk_pacing_shift: scaling factor for TCP Small Queues
293   *	@sk_lingertime: %SO_LINGER l_linger setting
294   *	@sk_backlog: always used with the per-socket spinlock held
295   *	@sk_callback_lock: used with the callbacks in the end of this struct
296   *	@sk_error_queue: rarely used
297   *	@sk_prot_creator: sk_prot of original sock creator (see ipv6_setsockopt,
298   *			  IPV6_ADDRFORM for instance)
299   *	@sk_err: last error
300   *	@sk_err_soft: errors that don't cause failure but are the cause of a
301   *		      persistent failure not just 'timed out'
302   *	@sk_drops: raw/udp drops counter
303   *	@sk_ack_backlog: current listen backlog
304   *	@sk_max_ack_backlog: listen backlog set in listen()
305   *	@sk_uid: user id of owner
306   *	@sk_prefer_busy_poll: prefer busypolling over softirq processing
307   *	@sk_busy_poll_budget: napi processing budget when busypolling
308   *	@sk_priority: %SO_PRIORITY setting
309   *	@sk_type: socket type (%SOCK_STREAM, etc)
310   *	@sk_protocol: which protocol this socket belongs in this network family
311   *	@sk_peer_lock: lock protecting @sk_peer_pid and @sk_peer_cred
312   *	@sk_peer_pid: &struct pid for this socket's peer
313   *	@sk_peer_cred: %SO_PEERCRED setting
314   *	@sk_rcvlowat: %SO_RCVLOWAT setting
315   *	@sk_rcvtimeo: %SO_RCVTIMEO setting
316   *	@sk_sndtimeo: %SO_SNDTIMEO setting
317   *	@sk_txhash: computed flow hash for use on transmit
318   *	@sk_filter: socket filtering instructions
319   *	@sk_timer: sock cleanup timer
320   *	@sk_stamp: time stamp of last packet received
321   *	@sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only
322   *	@sk_tsflags: SO_TIMESTAMPING flags
323   *	@sk_bind_phc: SO_TIMESTAMPING bind PHC index of PTP virtual clock
324   *	              for timestamping
325   *	@sk_tskey: counter to disambiguate concurrent tstamp requests
326   *	@sk_zckey: counter to order MSG_ZEROCOPY notifications
327   *	@sk_socket: Identd and reporting IO signals
328   *	@sk_user_data: RPC layer private data. Write-protected by @sk_callback_lock.
329   *	@sk_frag: cached page frag
330   *	@sk_peek_off: current peek_offset value
331   *	@sk_send_head: front of stuff to transmit
332   *	@tcp_rtx_queue: TCP re-transmit queue [union with @sk_send_head]
333   *	@sk_tx_skb_cache: cache copy of recently accessed TX skb
334   *	@sk_security: used by security modules
335   *	@sk_mark: generic packet mark
336   *	@sk_cgrp_data: cgroup data for this cgroup
337   *	@sk_memcg: this socket's memory cgroup association
338   *	@sk_write_pending: a write to stream socket waits to start
339   *	@sk_wait_pending: number of threads blocked on this socket
340   *	@sk_state_change: callback to indicate change in the state of the sock
341   *	@sk_data_ready: callback to indicate there is data to be processed
342   *	@sk_write_space: callback to indicate there is bf sending space available
343   *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
344   *	@sk_backlog_rcv: callback to process the backlog
345   *	@sk_validate_xmit_skb: ptr to an optional validate function
346   *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
347   *	@sk_reuseport_cb: reuseport group container
348   *	@sk_bpf_storage: ptr to cache and control for bpf_sk_storage
349   *	@sk_rcu: used during RCU grace period
350   *	@sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
351   *	@sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
352   *	@sk_txtime_report_errors: set report errors mode for SO_TXTIME
353   *	@sk_txtime_unused: unused txtime flags
354   */
355 struct sock {
356 	/*
357 	 * Now struct inet_timewait_sock also uses sock_common, so please just
358 	 * don't add nothing before this first member (__sk_common) --acme
359 	 */
360 	struct sock_common	__sk_common;
361 #define sk_node			__sk_common.skc_node
362 #define sk_nulls_node		__sk_common.skc_nulls_node
363 #define sk_refcnt		__sk_common.skc_refcnt
364 #define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
365 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
366 #define sk_rx_queue_mapping	__sk_common.skc_rx_queue_mapping
367 #endif
368 
369 #define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
370 #define sk_dontcopy_end		__sk_common.skc_dontcopy_end
371 #define sk_hash			__sk_common.skc_hash
372 #define sk_portpair		__sk_common.skc_portpair
373 #define sk_num			__sk_common.skc_num
374 #define sk_dport		__sk_common.skc_dport
375 #define sk_addrpair		__sk_common.skc_addrpair
376 #define sk_daddr		__sk_common.skc_daddr
377 #define sk_rcv_saddr		__sk_common.skc_rcv_saddr
378 #define sk_family		__sk_common.skc_family
379 #define sk_state		__sk_common.skc_state
380 #define sk_reuse		__sk_common.skc_reuse
381 #define sk_reuseport		__sk_common.skc_reuseport
382 #define sk_ipv6only		__sk_common.skc_ipv6only
383 #define sk_net_refcnt		__sk_common.skc_net_refcnt
384 #define sk_bound_dev_if		__sk_common.skc_bound_dev_if
385 #define sk_bind_node		__sk_common.skc_bind_node
386 #define sk_prot			__sk_common.skc_prot
387 #define sk_net			__sk_common.skc_net
388 #define sk_v6_daddr		__sk_common.skc_v6_daddr
389 #define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
390 #define sk_cookie		__sk_common.skc_cookie
391 #define sk_incoming_cpu		__sk_common.skc_incoming_cpu
392 #define sk_flags		__sk_common.skc_flags
393 #define sk_rxhash		__sk_common.skc_rxhash
394 
395 	socket_lock_t		sk_lock;
396 	atomic_t		sk_drops;
397 	int			sk_rcvlowat;
398 	struct sk_buff_head	sk_error_queue;
399 	struct sk_buff		*sk_rx_skb_cache;
400 	struct sk_buff_head	sk_receive_queue;
401 	/*
402 	 * The backlog queue is special, it is always used with
403 	 * the per-socket spinlock held and requires low latency
404 	 * access. Therefore we special case it's implementation.
405 	 * Note : rmem_alloc is in this structure to fill a hole
406 	 * on 64bit arches, not because its logically part of
407 	 * backlog.
408 	 */
409 	struct {
410 		atomic_t	rmem_alloc;
411 		int		len;
412 		struct sk_buff	*head;
413 		struct sk_buff	*tail;
414 	} sk_backlog;
415 #define sk_rmem_alloc sk_backlog.rmem_alloc
416 
417 	int			sk_forward_alloc;
418 #ifdef CONFIG_NET_RX_BUSY_POLL
419 	unsigned int		sk_ll_usec;
420 	/* ===== mostly read cache line ===== */
421 	unsigned int		sk_napi_id;
422 #endif
423 	int			sk_rcvbuf;
424 	int			sk_wait_pending;
425 
426 	struct sk_filter __rcu	*sk_filter;
427 	union {
428 		struct socket_wq __rcu	*sk_wq;
429 		/* private: */
430 		struct socket_wq	*sk_wq_raw;
431 		/* public: */
432 	};
433 #ifdef CONFIG_XFRM
434 	struct xfrm_policy __rcu *sk_policy[2];
435 #endif
436 	struct dst_entry __rcu	*sk_rx_dst;
437 	int			sk_rx_dst_ifindex;
438 	u32			sk_rx_dst_cookie;
439 
440 	struct dst_entry __rcu	*sk_dst_cache;
441 	atomic_t		sk_omem_alloc;
442 	int			sk_sndbuf;
443 
444 	/* ===== cache line for TX ===== */
445 	int			sk_wmem_queued;
446 	refcount_t		sk_wmem_alloc;
447 	unsigned long		sk_tsq_flags;
448 	union {
449 		struct sk_buff	*sk_send_head;
450 		struct rb_root	tcp_rtx_queue;
451 	};
452 	struct sk_buff		*sk_tx_skb_cache;
453 	struct sk_buff_head	sk_write_queue;
454 	__s32			sk_peek_off;
455 	int			sk_write_pending;
456 	__u32			sk_dst_pending_confirm;
457 	u32			sk_pacing_status; /* see enum sk_pacing */
458 	long			sk_sndtimeo;
459 	struct timer_list	sk_timer;
460 	__u32			sk_priority;
461 	__u32			sk_mark;
462 	unsigned long		sk_pacing_rate; /* bytes per second */
463 	unsigned long		sk_max_pacing_rate;
464 	struct page_frag	sk_frag;
465 	netdev_features_t	sk_route_caps;
466 	netdev_features_t	sk_route_nocaps;
467 	netdev_features_t	sk_route_forced_caps;
468 	int			sk_gso_type;
469 	unsigned int		sk_gso_max_size;
470 	gfp_t			sk_allocation;
471 	__u32			sk_txhash;
472 
473 	/*
474 	 * Because of non atomicity rules, all
475 	 * changes are protected by socket lock.
476 	 */
477 	u8			sk_padding : 1,
478 				sk_kern_sock : 1,
479 				sk_no_check_tx : 1,
480 				sk_no_check_rx : 1,
481 				sk_userlocks : 4;
482 	u8			sk_pacing_shift;
483 	u16			sk_type;
484 	u16			sk_protocol;
485 	u16			sk_gso_max_segs;
486 	unsigned long	        sk_lingertime;
487 	struct proto		*sk_prot_creator;
488 	rwlock_t		sk_callback_lock;
489 	int			sk_err,
490 				sk_err_soft;
491 	u32			sk_ack_backlog;
492 	u32			sk_max_ack_backlog;
493 	kuid_t			sk_uid;
494 #ifdef CONFIG_NET_RX_BUSY_POLL
495 	u8			sk_prefer_busy_poll;
496 	u16			sk_busy_poll_budget;
497 #endif
498 	spinlock_t		sk_peer_lock;
499 	struct pid		*sk_peer_pid;
500 	const struct cred	*sk_peer_cred;
501 
502 	long			sk_rcvtimeo;
503 	ktime_t			sk_stamp;
504 #if BITS_PER_LONG==32
505 	seqlock_t		sk_stamp_seq;
506 #endif
507 	u16			sk_tsflags;
508 	int			sk_bind_phc;
509 	u8			sk_shutdown;
510 	atomic_t		sk_tskey;
511 	atomic_t		sk_zckey;
512 
513 	u8			sk_clockid;
514 	u8			sk_txtime_deadline_mode : 1,
515 				sk_txtime_report_errors : 1,
516 				sk_txtime_unused : 6;
517 
518 	struct socket		*sk_socket;
519 	void			*sk_user_data;
520 #ifdef CONFIG_SECURITY
521 	void			*sk_security;
522 #endif
523 	struct sock_cgroup_data	sk_cgrp_data;
524 	struct mem_cgroup	*sk_memcg;
525 	void			(*sk_state_change)(struct sock *sk);
526 	void			(*sk_data_ready)(struct sock *sk);
527 	void			(*sk_write_space)(struct sock *sk);
528 	void			(*sk_error_report)(struct sock *sk);
529 	int			(*sk_backlog_rcv)(struct sock *sk,
530 						  struct sk_buff *skb);
531 #ifdef CONFIG_SOCK_VALIDATE_XMIT
532 	struct sk_buff*		(*sk_validate_xmit_skb)(struct sock *sk,
533 							struct net_device *dev,
534 							struct sk_buff *skb);
535 #endif
536 	void                    (*sk_destruct)(struct sock *sk);
537 	struct sock_reuseport __rcu	*sk_reuseport_cb;
538 #ifdef CONFIG_BPF_SYSCALL
539 	struct bpf_local_storage __rcu	*sk_bpf_storage;
540 #endif
541 	struct rcu_head		sk_rcu;
542 
543 	ANDROID_OEM_DATA(1);
544 	ANDROID_KABI_RESERVE(1);
545 	ANDROID_KABI_RESERVE(2);
546 	ANDROID_KABI_RESERVE(3);
547 	ANDROID_KABI_RESERVE(4);
548 	ANDROID_KABI_RESERVE(5);
549 	ANDROID_KABI_RESERVE(6);
550 	ANDROID_KABI_RESERVE(7);
551 	ANDROID_KABI_RESERVE(8);
552 };
553 
554 enum sk_pacing {
555 	SK_PACING_NONE		= 0,
556 	SK_PACING_NEEDED	= 1,
557 	SK_PACING_FQ		= 2,
558 };
559 
560 /* flag bits in sk_user_data
561  *
562  * - SK_USER_DATA_NOCOPY:      Pointer stored in sk_user_data might
563  *   not be suitable for copying when cloning the socket. For instance,
564  *   it can point to a reference counted object. sk_user_data bottom
565  *   bit is set if pointer must not be copied.
566  *
567  * - SK_USER_DATA_BPF:         Mark whether sk_user_data field is
568  *   managed/owned by a BPF reuseport array. This bit should be set
569  *   when sk_user_data's sk is added to the bpf's reuseport_array.
570  *
571  * - SK_USER_DATA_PSOCK:       Mark whether pointer stored in
572  *   sk_user_data points to psock type. This bit should be set
573  *   when sk_user_data is assigned to a psock object.
574  */
575 #define SK_USER_DATA_NOCOPY	1UL
576 #define SK_USER_DATA_BPF	2UL
577 #define SK_USER_DATA_PSOCK	4UL
578 #define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
579 				  SK_USER_DATA_PSOCK)
580 
581 /**
582  * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
583  * @sk: socket
584  */
sk_user_data_is_nocopy(const struct sock * sk)585 static inline bool sk_user_data_is_nocopy(const struct sock *sk)
586 {
587 	return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
588 }
589 
590 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
591 
592 /**
593  * __rcu_dereference_sk_user_data_with_flags - return the pointer
594  * only if argument flags all has been set in sk_user_data. Otherwise
595  * return NULL
596  *
597  * @sk: socket
598  * @flags: flag bits
599  */
600 static inline void *
__rcu_dereference_sk_user_data_with_flags(const struct sock * sk,uintptr_t flags)601 __rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
602 					  uintptr_t flags)
603 {
604 	uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
605 
606 	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
607 
608 	if ((sk_user_data & flags) == flags)
609 		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
610 	return NULL;
611 }
612 
613 #define rcu_dereference_sk_user_data(sk)				\
614 	__rcu_dereference_sk_user_data_with_flags(sk, 0)
615 #define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags)		\
616 ({									\
617 	uintptr_t __tmp1 = (uintptr_t)(ptr),				\
618 		  __tmp2 = (uintptr_t)(flags);				\
619 	WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK);			\
620 	WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK);			\
621 	rcu_assign_pointer(__sk_user_data((sk)),			\
622 			   __tmp1 | __tmp2);				\
623 })
624 #define rcu_assign_sk_user_data(sk, ptr)				\
625 	__rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
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 
sk_backlog_rcv(struct sock * sk,struct sk_buff * skb)1067 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1068 {
1069 	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1070 		return __sk_backlog_rcv(sk, skb);
1071 
1072 	return sk->sk_backlog_rcv(sk, skb);
1073 }
1074 
sk_incoming_cpu_update(struct sock * sk)1075 static inline void sk_incoming_cpu_update(struct sock *sk)
1076 {
1077 	int cpu = raw_smp_processor_id();
1078 
1079 	if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1080 		WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1081 }
1082 
sock_rps_record_flow_hash(__u32 hash)1083 static inline void sock_rps_record_flow_hash(__u32 hash)
1084 {
1085 #ifdef CONFIG_RPS
1086 	struct rps_sock_flow_table *sock_flow_table;
1087 
1088 	rcu_read_lock();
1089 	sock_flow_table = rcu_dereference(rps_sock_flow_table);
1090 	rps_record_sock_flow(sock_flow_table, hash);
1091 	rcu_read_unlock();
1092 #endif
1093 }
1094 
sock_rps_record_flow(const struct sock * sk)1095 static inline void sock_rps_record_flow(const struct sock *sk)
1096 {
1097 #ifdef CONFIG_RPS
1098 	if (static_branch_unlikely(&rfs_needed)) {
1099 		/* Reading sk->sk_rxhash might incur an expensive cache line
1100 		 * miss.
1101 		 *
1102 		 * TCP_ESTABLISHED does cover almost all states where RFS
1103 		 * might be useful, and is cheaper [1] than testing :
1104 		 *	IPv4: inet_sk(sk)->inet_daddr
1105 		 * 	IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
1106 		 * OR	an additional socket flag
1107 		 * [1] : sk_state and sk_prot are in the same cache line.
1108 		 */
1109 		if (sk->sk_state == TCP_ESTABLISHED) {
1110 			/* This READ_ONCE() is paired with the WRITE_ONCE()
1111 			 * from sock_rps_save_rxhash() and sock_rps_reset_rxhash().
1112 			 */
1113 			sock_rps_record_flow_hash(READ_ONCE(sk->sk_rxhash));
1114 		}
1115 	}
1116 #endif
1117 }
1118 
sock_rps_save_rxhash(struct sock * sk,const struct sk_buff * skb)1119 static inline void sock_rps_save_rxhash(struct sock *sk,
1120 					const struct sk_buff *skb)
1121 {
1122 #ifdef CONFIG_RPS
1123 	/* The following WRITE_ONCE() is paired with the READ_ONCE()
1124 	 * here, and another one in sock_rps_record_flow().
1125 	 */
1126 	if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash))
1127 		WRITE_ONCE(sk->sk_rxhash, skb->hash);
1128 #endif
1129 }
1130 
sock_rps_reset_rxhash(struct sock * sk)1131 static inline void sock_rps_reset_rxhash(struct sock *sk)
1132 {
1133 #ifdef CONFIG_RPS
1134 	/* Paired with READ_ONCE() in sock_rps_record_flow() */
1135 	WRITE_ONCE(sk->sk_rxhash, 0);
1136 #endif
1137 }
1138 
1139 #define sk_wait_event(__sk, __timeo, __condition, __wait)		\
1140 	({	int __rc;						\
1141 		__sk->sk_wait_pending++;				\
1142 		release_sock(__sk);					\
1143 		__rc = __condition;					\
1144 		if (!__rc) {						\
1145 			*(__timeo) = wait_woken(__wait,			\
1146 						TASK_INTERRUPTIBLE,	\
1147 						*(__timeo));		\
1148 		}							\
1149 		sched_annotate_sleep();					\
1150 		lock_sock(__sk);					\
1151 		__sk->sk_wait_pending--;				\
1152 		__rc = __condition;					\
1153 		__rc;							\
1154 	})
1155 
1156 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1157 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1158 void sk_stream_wait_close(struct sock *sk, long timeo_p);
1159 int sk_stream_error(struct sock *sk, int flags, int err);
1160 void sk_stream_kill_queues(struct sock *sk);
1161 void sk_set_memalloc(struct sock *sk);
1162 void sk_clear_memalloc(struct sock *sk);
1163 
1164 void __sk_flush_backlog(struct sock *sk);
1165 
sk_flush_backlog(struct sock * sk)1166 static inline bool sk_flush_backlog(struct sock *sk)
1167 {
1168 	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1169 		__sk_flush_backlog(sk);
1170 		return true;
1171 	}
1172 	return false;
1173 }
1174 
1175 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1176 
1177 struct request_sock_ops;
1178 struct timewait_sock_ops;
1179 struct inet_hashinfo;
1180 struct raw_hashinfo;
1181 struct smc_hashinfo;
1182 struct module;
1183 struct sk_psock;
1184 
1185 /*
1186  * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1187  * un-modified. Special care is taken when initializing object to zero.
1188  */
sk_prot_clear_nulls(struct sock * sk,int size)1189 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1190 {
1191 	if (offsetof(struct sock, sk_node.next) != 0)
1192 		memset(sk, 0, offsetof(struct sock, sk_node.next));
1193 	memset(&sk->sk_node.pprev, 0,
1194 	       size - offsetof(struct sock, sk_node.pprev));
1195 }
1196 
1197 /* Networking protocol blocks we attach to sockets.
1198  * socket layer -> transport layer interface
1199  */
1200 struct proto {
1201 	void			(*close)(struct sock *sk,
1202 					long timeout);
1203 	int			(*pre_connect)(struct sock *sk,
1204 					struct sockaddr *uaddr,
1205 					int addr_len);
1206 	int			(*connect)(struct sock *sk,
1207 					struct sockaddr *uaddr,
1208 					int addr_len);
1209 	int			(*disconnect)(struct sock *sk, int flags);
1210 
1211 	struct sock *		(*accept)(struct sock *sk, int flags, int *err,
1212 					  bool kern);
1213 
1214 	int			(*ioctl)(struct sock *sk, int cmd,
1215 					 unsigned long arg);
1216 	int			(*init)(struct sock *sk);
1217 	void			(*destroy)(struct sock *sk);
1218 	void			(*shutdown)(struct sock *sk, int how);
1219 	int			(*setsockopt)(struct sock *sk, int level,
1220 					int optname, sockptr_t optval,
1221 					unsigned int optlen);
1222 	int			(*getsockopt)(struct sock *sk, int level,
1223 					int optname, char __user *optval,
1224 					int __user *option);
1225 	void			(*keepalive)(struct sock *sk, int valbool);
1226 #ifdef CONFIG_COMPAT
1227 	int			(*compat_ioctl)(struct sock *sk,
1228 					unsigned int cmd, unsigned long arg);
1229 #endif
1230 	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
1231 					   size_t len);
1232 	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
1233 					   size_t len, int noblock, int flags,
1234 					   int *addr_len);
1235 	int			(*sendpage)(struct sock *sk, struct page *page,
1236 					int offset, size_t size, int flags);
1237 	int			(*bind)(struct sock *sk,
1238 					struct sockaddr *addr, int addr_len);
1239 	int			(*bind_add)(struct sock *sk,
1240 					struct sockaddr *addr, int addr_len);
1241 
1242 	int			(*backlog_rcv) (struct sock *sk,
1243 						struct sk_buff *skb);
1244 	bool			(*bpf_bypass_getsockopt)(int level,
1245 							 int optname);
1246 
1247 	void		(*release_cb)(struct sock *sk);
1248 
1249 	/* Keeping track of sk's, looking them up, and port selection methods. */
1250 	int			(*hash)(struct sock *sk);
1251 	void			(*unhash)(struct sock *sk);
1252 	void			(*rehash)(struct sock *sk);
1253 	int			(*get_port)(struct sock *sk, unsigned short snum);
1254 #ifdef CONFIG_BPF_SYSCALL
1255 	int			(*psock_update_sk_prot)(struct sock *sk,
1256 							struct sk_psock *psock,
1257 							bool restore);
1258 #endif
1259 
1260 	/* Keeping track of sockets in use */
1261 #ifdef CONFIG_PROC_FS
1262 	unsigned int		inuse_idx;
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 	 * Pressure flag: try to collapse.
1274 	 * Technical note: it is used by multiple contexts non atomically.
1275 	 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes.
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_stream_memory_free(const struct sock * sk,int wake)1350 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1351 {
1352 	if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1353 		return false;
1354 
1355 #ifdef CONFIG_INET
1356 	return sk->sk_prot->stream_memory_free ?
1357 		INDIRECT_CALL_1(sk->sk_prot->stream_memory_free,
1358 			        tcp_stream_memory_free,
1359 				sk, wake) : true;
1360 #else
1361 	return sk->sk_prot->stream_memory_free ?
1362 		sk->sk_prot->stream_memory_free(sk, wake) : true;
1363 #endif
1364 }
1365 
sk_stream_memory_free(const struct sock * sk)1366 static inline bool sk_stream_memory_free(const struct sock *sk)
1367 {
1368 	return __sk_stream_memory_free(sk, 0);
1369 }
1370 
__sk_stream_is_writeable(const struct sock * sk,int wake)1371 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1372 {
1373 	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1374 	       __sk_stream_memory_free(sk, wake);
1375 }
1376 
sk_stream_is_writeable(const struct sock * sk)1377 static inline bool sk_stream_is_writeable(const struct sock *sk)
1378 {
1379 	return __sk_stream_is_writeable(sk, 0);
1380 }
1381 
sk_under_cgroup_hierarchy(struct sock * sk,struct cgroup * ancestor)1382 static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1383 					    struct cgroup *ancestor)
1384 {
1385 #ifdef CONFIG_SOCK_CGROUP_DATA
1386 	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1387 				    ancestor);
1388 #else
1389 	return -ENOTSUPP;
1390 #endif
1391 }
1392 
sk_has_memory_pressure(const struct sock * sk)1393 static inline bool sk_has_memory_pressure(const struct sock *sk)
1394 {
1395 	return sk->sk_prot->memory_pressure != NULL;
1396 }
1397 
sk_under_global_memory_pressure(const struct sock * sk)1398 static inline bool sk_under_global_memory_pressure(const struct sock *sk)
1399 {
1400 	return sk->sk_prot->memory_pressure &&
1401 		!!READ_ONCE(*sk->sk_prot->memory_pressure);
1402 }
1403 
sk_under_memory_pressure(const struct sock * sk)1404 static inline bool sk_under_memory_pressure(const struct sock *sk)
1405 {
1406 	if (!sk->sk_prot->memory_pressure)
1407 		return false;
1408 
1409 	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1410 	    mem_cgroup_under_socket_pressure(sk->sk_memcg))
1411 		return true;
1412 
1413 	return !!READ_ONCE(*sk->sk_prot->memory_pressure);
1414 }
1415 
1416 static inline long
sk_memory_allocated(const struct sock * sk)1417 sk_memory_allocated(const struct sock *sk)
1418 {
1419 	return atomic_long_read(sk->sk_prot->memory_allocated);
1420 }
1421 
1422 static inline long
sk_memory_allocated_add(struct sock * sk,int amt)1423 sk_memory_allocated_add(struct sock *sk, int amt)
1424 {
1425 	return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1426 }
1427 
1428 static inline void
sk_memory_allocated_sub(struct sock * sk,int amt)1429 sk_memory_allocated_sub(struct sock *sk, int amt)
1430 {
1431 	atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1432 }
1433 
1434 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1435 
sk_sockets_allocated_dec(struct sock * sk)1436 static inline void sk_sockets_allocated_dec(struct sock *sk)
1437 {
1438 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1439 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1440 }
1441 
sk_sockets_allocated_inc(struct sock * sk)1442 static inline void sk_sockets_allocated_inc(struct sock *sk)
1443 {
1444 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1445 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1446 }
1447 
1448 static inline u64
sk_sockets_allocated_read_positive(struct sock * sk)1449 sk_sockets_allocated_read_positive(struct sock *sk)
1450 {
1451 	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1452 }
1453 
1454 static inline int
proto_sockets_allocated_sum_positive(struct proto * prot)1455 proto_sockets_allocated_sum_positive(struct proto *prot)
1456 {
1457 	return percpu_counter_sum_positive(prot->sockets_allocated);
1458 }
1459 
1460 static inline long
proto_memory_allocated(struct proto * prot)1461 proto_memory_allocated(struct proto *prot)
1462 {
1463 	return atomic_long_read(prot->memory_allocated);
1464 }
1465 
1466 static inline bool
proto_memory_pressure(struct proto * prot)1467 proto_memory_pressure(struct proto *prot)
1468 {
1469 	if (!prot->memory_pressure)
1470 		return false;
1471 	return !!READ_ONCE(*prot->memory_pressure);
1472 }
1473 
1474 
1475 #ifdef CONFIG_PROC_FS
1476 /* Called with local bh disabled */
1477 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1478 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1479 int sock_inuse_get(struct net *net);
1480 #else
sock_prot_inuse_add(struct net * net,struct proto * prot,int inc)1481 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1482 		int inc)
1483 {
1484 }
1485 #endif
1486 
1487 
1488 /* With per-bucket locks this operation is not-atomic, so that
1489  * this version is not worse.
1490  */
__sk_prot_rehash(struct sock * sk)1491 static inline int __sk_prot_rehash(struct sock *sk)
1492 {
1493 	sk->sk_prot->unhash(sk);
1494 	return sk->sk_prot->hash(sk);
1495 }
1496 
1497 /* About 10 seconds */
1498 #define SOCK_DESTROY_TIME (10*HZ)
1499 
1500 /* Sockets 0-1023 can't be bound to unless you are superuser */
1501 #define PROT_SOCK	1024
1502 
1503 #define SHUTDOWN_MASK	3
1504 #define RCV_SHUTDOWN	1
1505 #define SEND_SHUTDOWN	2
1506 
1507 #define SOCK_BINDADDR_LOCK	4
1508 #define SOCK_BINDPORT_LOCK	8
1509 
1510 struct socket_alloc {
1511 	struct socket socket;
1512 	struct inode vfs_inode;
1513 };
1514 
SOCKET_I(struct inode * inode)1515 static inline struct socket *SOCKET_I(struct inode *inode)
1516 {
1517 	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1518 }
1519 
SOCK_INODE(struct socket * socket)1520 static inline struct inode *SOCK_INODE(struct socket *socket)
1521 {
1522 	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1523 }
1524 
1525 /*
1526  * Functions for memory accounting
1527  */
1528 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1529 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1530 void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1531 void __sk_mem_reclaim(struct sock *sk, int amount);
1532 
1533 /* We used to have PAGE_SIZE here, but systems with 64KB pages
1534  * do not necessarily have 16x time more memory than 4KB ones.
1535  */
1536 #define SK_MEM_QUANTUM 4096
1537 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1538 #define SK_MEM_SEND	0
1539 #define SK_MEM_RECV	1
1540 
1541 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
sk_prot_mem_limits(const struct sock * sk,int index)1542 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1543 {
1544 	long val = READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1545 
1546 #if PAGE_SIZE > SK_MEM_QUANTUM
1547 	val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1548 #elif PAGE_SIZE < SK_MEM_QUANTUM
1549 	val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1550 #endif
1551 	return val;
1552 }
1553 
sk_mem_pages(int amt)1554 static inline int sk_mem_pages(int amt)
1555 {
1556 	return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1557 }
1558 
sk_has_account(struct sock * sk)1559 static inline bool sk_has_account(struct sock *sk)
1560 {
1561 	/* return true if protocol supports memory accounting */
1562 	return !!sk->sk_prot->memory_allocated;
1563 }
1564 
sk_wmem_schedule(struct sock * sk,int size)1565 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1566 {
1567 	int delta;
1568 
1569 	if (!sk_has_account(sk))
1570 		return true;
1571 	delta = size - sk->sk_forward_alloc;
1572 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND);
1573 }
1574 
1575 static inline bool
sk_rmem_schedule(struct sock * sk,struct sk_buff * skb,int size)1576 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1577 {
1578 	int delta;
1579 
1580 	if (!sk_has_account(sk))
1581 		return true;
1582 	delta = size - sk->sk_forward_alloc;
1583 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) ||
1584 		skb_pfmemalloc(skb);
1585 }
1586 
sk_mem_reclaim(struct sock * sk)1587 static inline void sk_mem_reclaim(struct sock *sk)
1588 {
1589 	if (!sk_has_account(sk))
1590 		return;
1591 	if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1592 		__sk_mem_reclaim(sk, sk->sk_forward_alloc);
1593 }
1594 
sk_mem_reclaim_partial(struct sock * sk)1595 static inline void sk_mem_reclaim_partial(struct sock *sk)
1596 {
1597 	if (!sk_has_account(sk))
1598 		return;
1599 	if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1600 		__sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1601 }
1602 
sk_mem_charge(struct sock * sk,int size)1603 static inline void sk_mem_charge(struct sock *sk, int size)
1604 {
1605 	if (!sk_has_account(sk))
1606 		return;
1607 	sk->sk_forward_alloc -= size;
1608 }
1609 
sk_mem_uncharge(struct sock * sk,int size)1610 static inline void sk_mem_uncharge(struct sock *sk, int size)
1611 {
1612 	if (!sk_has_account(sk))
1613 		return;
1614 	sk->sk_forward_alloc += size;
1615 
1616 	/* Avoid a possible overflow.
1617 	 * TCP send queues can make this happen, if sk_mem_reclaim()
1618 	 * is not called and more than 2 GBytes are released at once.
1619 	 *
1620 	 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1621 	 * no need to hold that much forward allocation anyway.
1622 	 */
1623 	if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1624 		__sk_mem_reclaim(sk, 1 << 20);
1625 }
1626 
1627 DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key);
sk_wmem_free_skb(struct sock * sk,struct sk_buff * skb)1628 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1629 {
1630 	sk_wmem_queued_add(sk, -skb->truesize);
1631 	sk_mem_uncharge(sk, skb->truesize);
1632 	if (static_branch_unlikely(&tcp_tx_skb_cache_key) &&
1633 	    !sk->sk_tx_skb_cache && !skb_cloned(skb)) {
1634 		skb_ext_reset(skb);
1635 		skb_zcopy_clear(skb, true);
1636 		sk->sk_tx_skb_cache = skb;
1637 		return;
1638 	}
1639 	__kfree_skb(skb);
1640 }
1641 
sock_release_ownership(struct sock * sk)1642 static inline void sock_release_ownership(struct sock *sk)
1643 {
1644 	if (sk->sk_lock.owned) {
1645 		sk->sk_lock.owned = 0;
1646 
1647 		/* The sk_lock has mutex_unlock() semantics: */
1648 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1649 	}
1650 }
1651 
1652 /*
1653  * Macro so as to not evaluate some arguments when
1654  * lockdep is not enabled.
1655  *
1656  * Mark both the sk_lock and the sk_lock.slock as a
1657  * per-address-family lock class.
1658  */
1659 #define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1660 do {									\
1661 	sk->sk_lock.owned = 0;						\
1662 	init_waitqueue_head(&sk->sk_lock.wq);				\
1663 	spin_lock_init(&(sk)->sk_lock.slock);				\
1664 	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1665 			sizeof((sk)->sk_lock));				\
1666 	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1667 				(skey), (sname));				\
1668 	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1669 } while (0)
1670 
lockdep_sock_is_held(const struct sock * sk)1671 static inline bool lockdep_sock_is_held(const struct sock *sk)
1672 {
1673 	return lockdep_is_held(&sk->sk_lock) ||
1674 	       lockdep_is_held(&sk->sk_lock.slock);
1675 }
1676 
1677 void lock_sock_nested(struct sock *sk, int subclass);
1678 
lock_sock(struct sock * sk)1679 static inline void lock_sock(struct sock *sk)
1680 {
1681 	lock_sock_nested(sk, 0);
1682 }
1683 
1684 void __lock_sock(struct sock *sk);
1685 void __release_sock(struct sock *sk);
1686 void release_sock(struct sock *sk);
1687 
1688 /* BH context may only use the following locking interface. */
1689 #define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1690 #define bh_lock_sock_nested(__sk) \
1691 				spin_lock_nested(&((__sk)->sk_lock.slock), \
1692 				SINGLE_DEPTH_NESTING)
1693 #define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1694 
1695 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1696 
1697 /**
1698  * lock_sock_fast - fast version of lock_sock
1699  * @sk: socket
1700  *
1701  * This version should be used for very small section, where process wont block
1702  * return false if fast path is taken:
1703  *
1704  *   sk_lock.slock locked, owned = 0, BH disabled
1705  *
1706  * return true if slow path is taken:
1707  *
1708  *   sk_lock.slock unlocked, owned = 1, BH enabled
1709  */
lock_sock_fast(struct sock * sk)1710 static inline bool lock_sock_fast(struct sock *sk)
1711 {
1712 	/* The sk_lock has mutex_lock() semantics here. */
1713 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1714 
1715 	return __lock_sock_fast(sk);
1716 }
1717 
1718 /* fast socket lock variant for caller already holding a [different] socket lock */
lock_sock_fast_nested(struct sock * sk)1719 static inline bool lock_sock_fast_nested(struct sock *sk)
1720 {
1721 	mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1722 
1723 	return __lock_sock_fast(sk);
1724 }
1725 
1726 /**
1727  * unlock_sock_fast - complement of lock_sock_fast
1728  * @sk: socket
1729  * @slow: slow mode
1730  *
1731  * fast unlock socket for user context.
1732  * If slow mode is on, we call regular release_sock()
1733  */
unlock_sock_fast(struct sock * sk,bool slow)1734 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1735 	__releases(&sk->sk_lock.slock)
1736 {
1737 	if (slow) {
1738 		release_sock(sk);
1739 		__release(&sk->sk_lock.slock);
1740 	} else {
1741 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1742 		spin_unlock_bh(&sk->sk_lock.slock);
1743 	}
1744 }
1745 
1746 /* Used by processes to "lock" a socket state, so that
1747  * interrupts and bottom half handlers won't change it
1748  * from under us. It essentially blocks any incoming
1749  * packets, so that we won't get any new data or any
1750  * packets that change the state of the socket.
1751  *
1752  * While locked, BH processing will add new packets to
1753  * the backlog queue.  This queue is processed by the
1754  * owner of the socket lock right before it is released.
1755  *
1756  * Since ~2.3.5 it is also exclusive sleep lock serializing
1757  * accesses from user process context.
1758  */
1759 
sock_owned_by_me(const struct sock * sk)1760 static inline void sock_owned_by_me(const struct sock *sk)
1761 {
1762 #ifdef CONFIG_LOCKDEP
1763 	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1764 #endif
1765 }
1766 
sock_owned_by_user(const struct sock * sk)1767 static inline bool sock_owned_by_user(const struct sock *sk)
1768 {
1769 	sock_owned_by_me(sk);
1770 	return sk->sk_lock.owned;
1771 }
1772 
sock_owned_by_user_nocheck(const struct sock * sk)1773 static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1774 {
1775 	return sk->sk_lock.owned;
1776 }
1777 
1778 /* no reclassification while locks are held */
sock_allow_reclassification(const struct sock * csk)1779 static inline bool sock_allow_reclassification(const struct sock *csk)
1780 {
1781 	struct sock *sk = (struct sock *)csk;
1782 
1783 	return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
1784 }
1785 
1786 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1787 		      struct proto *prot, int kern);
1788 void sk_free(struct sock *sk);
1789 void sk_destruct(struct sock *sk);
1790 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1791 void sk_free_unlock_clone(struct sock *sk);
1792 
1793 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1794 			     gfp_t priority);
1795 void __sock_wfree(struct sk_buff *skb);
1796 void sock_wfree(struct sk_buff *skb);
1797 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1798 			     gfp_t priority);
1799 void skb_orphan_partial(struct sk_buff *skb);
1800 void sock_rfree(struct sk_buff *skb);
1801 void sock_efree(struct sk_buff *skb);
1802 #ifdef CONFIG_INET
1803 void sock_edemux(struct sk_buff *skb);
1804 void sock_pfree(struct sk_buff *skb);
1805 #else
1806 #define sock_edemux sock_efree
1807 #endif
1808 
1809 int sock_setsockopt(struct socket *sock, int level, int op,
1810 		    sockptr_t optval, unsigned int optlen);
1811 
1812 int sock_getsockopt(struct socket *sock, int level, int op,
1813 		    char __user *optval, int __user *optlen);
1814 int sock_gettstamp(struct socket *sock, void __user *userstamp,
1815 		   bool timeval, bool time32);
1816 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1817 				    int noblock, int *errcode);
1818 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1819 				     unsigned long data_len, int noblock,
1820 				     int *errcode, int max_page_order);
1821 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1822 void sock_kfree_s(struct sock *sk, void *mem, int size);
1823 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1824 void sk_send_sigurg(struct sock *sk);
1825 
1826 struct sockcm_cookie {
1827 	u64 transmit_time;
1828 	u32 mark;
1829 	u16 tsflags;
1830 };
1831 
sockcm_init(struct sockcm_cookie * sockc,const struct sock * sk)1832 static inline void sockcm_init(struct sockcm_cookie *sockc,
1833 			       const struct sock *sk)
1834 {
1835 	*sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
1836 }
1837 
1838 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1839 		     struct sockcm_cookie *sockc);
1840 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1841 		   struct sockcm_cookie *sockc);
1842 
1843 /*
1844  * Functions to fill in entries in struct proto_ops when a protocol
1845  * does not implement a particular function.
1846  */
1847 int sock_no_bind(struct socket *, struct sockaddr *, int);
1848 int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1849 int sock_no_socketpair(struct socket *, struct socket *);
1850 int sock_no_accept(struct socket *, struct socket *, int, bool);
1851 int sock_no_getname(struct socket *, struct sockaddr *, int);
1852 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1853 int sock_no_listen(struct socket *, int);
1854 int sock_no_shutdown(struct socket *, int);
1855 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1856 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1857 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1858 int sock_no_mmap(struct file *file, struct socket *sock,
1859 		 struct vm_area_struct *vma);
1860 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1861 			 size_t size, int flags);
1862 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1863 				int offset, size_t size, int flags);
1864 
1865 /*
1866  * Functions to fill in entries in struct proto_ops when a protocol
1867  * uses the inet style.
1868  */
1869 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1870 				  char __user *optval, int __user *optlen);
1871 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1872 			int flags);
1873 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1874 			   sockptr_t optval, unsigned int optlen);
1875 
1876 void sk_common_release(struct sock *sk);
1877 
1878 /*
1879  *	Default socket callbacks and setup code
1880  */
1881 
1882 /* Initialise core socket variables using an explicit uid. */
1883 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid);
1884 
1885 /* Initialise core socket variables.
1886  * Assumes struct socket *sock is embedded in a struct socket_alloc.
1887  */
1888 void sock_init_data(struct socket *sock, struct sock *sk);
1889 
1890 /*
1891  * Socket reference counting postulates.
1892  *
1893  * * Each user of socket SHOULD hold a reference count.
1894  * * Each access point to socket (an hash table bucket, reference from a list,
1895  *   running timer, skb in flight MUST hold a reference count.
1896  * * When reference count hits 0, it means it will never increase back.
1897  * * When reference count hits 0, it means that no references from
1898  *   outside exist to this socket and current process on current CPU
1899  *   is last user and may/should destroy this socket.
1900  * * sk_free is called from any context: process, BH, IRQ. When
1901  *   it is called, socket has no references from outside -> sk_free
1902  *   may release descendant resources allocated by the socket, but
1903  *   to the time when it is called, socket is NOT referenced by any
1904  *   hash tables, lists etc.
1905  * * Packets, delivered from outside (from network or from another process)
1906  *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1907  *   when they sit in queue. Otherwise, packets will leak to hole, when
1908  *   socket is looked up by one cpu and unhasing is made by another CPU.
1909  *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1910  *   (leak to backlog). Packet socket does all the processing inside
1911  *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1912  *   use separate SMP lock, so that they are prone too.
1913  */
1914 
1915 /* Ungrab socket and destroy it, if it was the last reference. */
sock_put(struct sock * sk)1916 static inline void sock_put(struct sock *sk)
1917 {
1918 	if (refcount_dec_and_test(&sk->sk_refcnt))
1919 		sk_free(sk);
1920 }
1921 /* Generic version of sock_put(), dealing with all sockets
1922  * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1923  */
1924 void sock_gen_put(struct sock *sk);
1925 
1926 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1927 		     unsigned int trim_cap, bool refcounted);
sk_receive_skb(struct sock * sk,struct sk_buff * skb,const int nested)1928 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1929 				 const int nested)
1930 {
1931 	return __sk_receive_skb(sk, skb, nested, 1, true);
1932 }
1933 
sk_tx_queue_set(struct sock * sk,int tx_queue)1934 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1935 {
1936 	/* sk_tx_queue_mapping accept only upto a 16-bit value */
1937 	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1938 		return;
1939 	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1940 	 * other WRITE_ONCE() because socket lock might be not held.
1941 	 */
1942 	WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);
1943 }
1944 
1945 #define NO_QUEUE_MAPPING	USHRT_MAX
1946 
sk_tx_queue_clear(struct sock * sk)1947 static inline void sk_tx_queue_clear(struct sock *sk)
1948 {
1949 	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1950 	 * other WRITE_ONCE() because socket lock might be not held.
1951 	 */
1952 	WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);
1953 }
1954 
sk_tx_queue_get(const struct sock * sk)1955 static inline int sk_tx_queue_get(const struct sock *sk)
1956 {
1957 	if (sk) {
1958 		/* Paired with WRITE_ONCE() in sk_tx_queue_clear()
1959 		 * and sk_tx_queue_set().
1960 		 */
1961 		int val = READ_ONCE(sk->sk_tx_queue_mapping);
1962 
1963 		if (val != NO_QUEUE_MAPPING)
1964 			return val;
1965 	}
1966 	return -1;
1967 }
1968 
sk_rx_queue_set(struct sock * sk,const struct sk_buff * skb)1969 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1970 {
1971 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1972 	if (skb_rx_queue_recorded(skb)) {
1973 		u16 rx_queue = skb_get_rx_queue(skb);
1974 
1975 		if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING))
1976 			return;
1977 
1978 		sk->sk_rx_queue_mapping = rx_queue;
1979 	}
1980 #endif
1981 }
1982 
sk_rx_queue_clear(struct sock * sk)1983 static inline void sk_rx_queue_clear(struct sock *sk)
1984 {
1985 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1986 	sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING;
1987 #endif
1988 }
1989 
sk_rx_queue_get(const struct sock * sk)1990 static inline int sk_rx_queue_get(const struct sock *sk)
1991 {
1992 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1993 	if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING)
1994 		return sk->sk_rx_queue_mapping;
1995 #endif
1996 
1997 	return -1;
1998 }
1999 
sk_set_socket(struct sock * sk,struct socket * sock)2000 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
2001 {
2002 	sk->sk_socket = sock;
2003 }
2004 
sk_sleep(struct sock * sk)2005 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2006 {
2007 	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2008 	return &rcu_dereference_raw(sk->sk_wq)->wait;
2009 }
2010 /* Detach socket from process context.
2011  * Announce socket dead, detach it from wait queue and inode.
2012  * Note that parent inode held reference count on this struct sock,
2013  * we do not release it in this function, because protocol
2014  * probably wants some additional cleanups or even continuing
2015  * to work with this socket (TCP).
2016  */
sock_orphan(struct sock * sk)2017 static inline void sock_orphan(struct sock *sk)
2018 {
2019 	write_lock_bh(&sk->sk_callback_lock);
2020 	sock_set_flag(sk, SOCK_DEAD);
2021 	sk_set_socket(sk, NULL);
2022 	sk->sk_wq  = NULL;
2023 	write_unlock_bh(&sk->sk_callback_lock);
2024 }
2025 
sock_graft(struct sock * sk,struct socket * parent)2026 static inline void sock_graft(struct sock *sk, struct socket *parent)
2027 {
2028 	WARN_ON(parent->sk);
2029 	write_lock_bh(&sk->sk_callback_lock);
2030 	rcu_assign_pointer(sk->sk_wq, &parent->wq);
2031 	parent->sk = sk;
2032 	sk_set_socket(sk, parent);
2033 	sk->sk_uid = SOCK_INODE(parent)->i_uid;
2034 	security_sock_graft(sk, parent);
2035 	write_unlock_bh(&sk->sk_callback_lock);
2036 }
2037 
2038 kuid_t sock_i_uid(struct sock *sk);
2039 unsigned long __sock_i_ino(struct sock *sk);
2040 unsigned long sock_i_ino(struct sock *sk);
2041 
sock_net_uid(const struct net * net,const struct sock * sk)2042 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2043 {
2044 	return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
2045 }
2046 
net_tx_rndhash(void)2047 static inline u32 net_tx_rndhash(void)
2048 {
2049 	u32 v = prandom_u32();
2050 
2051 	return v ?: 1;
2052 }
2053 
sk_set_txhash(struct sock * sk)2054 static inline void sk_set_txhash(struct sock *sk)
2055 {
2056 	/* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2057 	WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2058 }
2059 
sk_rethink_txhash(struct sock * sk)2060 static inline bool sk_rethink_txhash(struct sock *sk)
2061 {
2062 	if (sk->sk_txhash) {
2063 		sk_set_txhash(sk);
2064 		return true;
2065 	}
2066 	return false;
2067 }
2068 
2069 static inline struct dst_entry *
__sk_dst_get(struct sock * sk)2070 __sk_dst_get(struct sock *sk)
2071 {
2072 	return rcu_dereference_check(sk->sk_dst_cache,
2073 				     lockdep_sock_is_held(sk));
2074 }
2075 
2076 static inline struct dst_entry *
sk_dst_get(struct sock * sk)2077 sk_dst_get(struct sock *sk)
2078 {
2079 	struct dst_entry *dst;
2080 
2081 	rcu_read_lock();
2082 	dst = rcu_dereference(sk->sk_dst_cache);
2083 	if (dst && !atomic_inc_not_zero(&dst->__refcnt))
2084 		dst = NULL;
2085 	rcu_read_unlock();
2086 	return dst;
2087 }
2088 
__dst_negative_advice(struct sock * sk)2089 static inline void __dst_negative_advice(struct sock *sk)
2090 {
2091 	struct dst_entry *ndst, *dst = __sk_dst_get(sk);
2092 
2093 	if (dst && dst->ops->negative_advice) {
2094 		ndst = dst->ops->negative_advice(dst);
2095 
2096 		if (ndst != dst) {
2097 			rcu_assign_pointer(sk->sk_dst_cache, ndst);
2098 			sk_tx_queue_clear(sk);
2099 			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2100 		}
2101 	}
2102 }
2103 
dst_negative_advice(struct sock * sk)2104 static inline void dst_negative_advice(struct sock *sk)
2105 {
2106 	sk_rethink_txhash(sk);
2107 	__dst_negative_advice(sk);
2108 }
2109 
2110 static inline void
__sk_dst_set(struct sock * sk,struct dst_entry * dst)2111 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
2112 {
2113 	struct dst_entry *old_dst;
2114 
2115 	sk_tx_queue_clear(sk);
2116 	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2117 	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2118 					    lockdep_sock_is_held(sk));
2119 	rcu_assign_pointer(sk->sk_dst_cache, dst);
2120 	dst_release(old_dst);
2121 }
2122 
2123 static inline void
sk_dst_set(struct sock * sk,struct dst_entry * dst)2124 sk_dst_set(struct sock *sk, struct dst_entry *dst)
2125 {
2126 	struct dst_entry *old_dst;
2127 
2128 	sk_tx_queue_clear(sk);
2129 	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2130 	old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2131 	dst_release(old_dst);
2132 }
2133 
2134 static inline void
__sk_dst_reset(struct sock * sk)2135 __sk_dst_reset(struct sock *sk)
2136 {
2137 	__sk_dst_set(sk, NULL);
2138 }
2139 
2140 static inline void
sk_dst_reset(struct sock * sk)2141 sk_dst_reset(struct sock *sk)
2142 {
2143 	sk_dst_set(sk, NULL);
2144 }
2145 
2146 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2147 
2148 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2149 
sk_dst_confirm(struct sock * sk)2150 static inline void sk_dst_confirm(struct sock *sk)
2151 {
2152 	if (!READ_ONCE(sk->sk_dst_pending_confirm))
2153 		WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2154 }
2155 
sock_confirm_neigh(struct sk_buff * skb,struct neighbour * n)2156 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2157 {
2158 	if (skb_get_dst_pending_confirm(skb)) {
2159 		struct sock *sk = skb->sk;
2160 		unsigned long now = jiffies;
2161 
2162 		/* avoid dirtying neighbour */
2163 		if (READ_ONCE(n->confirmed) != now)
2164 			WRITE_ONCE(n->confirmed, now);
2165 		if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2166 			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2167 	}
2168 }
2169 
2170 bool sk_mc_loop(struct sock *sk);
2171 
sk_can_gso(const struct sock * sk)2172 static inline bool sk_can_gso(const struct sock *sk)
2173 {
2174 	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2175 }
2176 
2177 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2178 
sk_nocaps_add(struct sock * sk,netdev_features_t flags)2179 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
2180 {
2181 	sk->sk_route_nocaps |= flags;
2182 	sk->sk_route_caps &= ~flags;
2183 }
2184 
skb_do_copy_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,char * to,int copy,int offset)2185 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2186 					   struct iov_iter *from, char *to,
2187 					   int copy, int offset)
2188 {
2189 	if (skb->ip_summed == CHECKSUM_NONE) {
2190 		__wsum csum = 0;
2191 		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2192 			return -EFAULT;
2193 		skb->csum = csum_block_add(skb->csum, csum, offset);
2194 	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2195 		if (!copy_from_iter_full_nocache(to, copy, from))
2196 			return -EFAULT;
2197 	} else if (!copy_from_iter_full(to, copy, from))
2198 		return -EFAULT;
2199 
2200 	return 0;
2201 }
2202 
skb_add_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,int copy)2203 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2204 				       struct iov_iter *from, int copy)
2205 {
2206 	int err, offset = skb->len;
2207 
2208 	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2209 				       copy, offset);
2210 	if (err)
2211 		__skb_trim(skb, offset);
2212 
2213 	return err;
2214 }
2215 
skb_copy_to_page_nocache(struct sock * sk,struct iov_iter * from,struct sk_buff * skb,struct page * page,int off,int copy)2216 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2217 					   struct sk_buff *skb,
2218 					   struct page *page,
2219 					   int off, int copy)
2220 {
2221 	int err;
2222 
2223 	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2224 				       copy, skb->len);
2225 	if (err)
2226 		return err;
2227 
2228 	skb->len	     += copy;
2229 	skb->data_len	     += copy;
2230 	skb->truesize	     += copy;
2231 	sk_wmem_queued_add(sk, copy);
2232 	sk_mem_charge(sk, copy);
2233 	return 0;
2234 }
2235 
2236 /**
2237  * sk_wmem_alloc_get - returns write allocations
2238  * @sk: socket
2239  *
2240  * Return: sk_wmem_alloc minus initial offset of one
2241  */
sk_wmem_alloc_get(const struct sock * sk)2242 static inline int sk_wmem_alloc_get(const struct sock *sk)
2243 {
2244 	return refcount_read(&sk->sk_wmem_alloc) - 1;
2245 }
2246 
2247 /**
2248  * sk_rmem_alloc_get - returns read allocations
2249  * @sk: socket
2250  *
2251  * Return: sk_rmem_alloc
2252  */
sk_rmem_alloc_get(const struct sock * sk)2253 static inline int sk_rmem_alloc_get(const struct sock *sk)
2254 {
2255 	return atomic_read(&sk->sk_rmem_alloc);
2256 }
2257 
2258 /**
2259  * sk_has_allocations - check if allocations are outstanding
2260  * @sk: socket
2261  *
2262  * Return: true if socket has write or read allocations
2263  */
sk_has_allocations(const struct sock * sk)2264 static inline bool sk_has_allocations(const struct sock *sk)
2265 {
2266 	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2267 }
2268 
2269 /**
2270  * skwq_has_sleeper - check if there are any waiting processes
2271  * @wq: struct socket_wq
2272  *
2273  * Return: true if socket_wq has waiting processes
2274  *
2275  * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2276  * barrier call. They were added due to the race found within the tcp code.
2277  *
2278  * Consider following tcp code paths::
2279  *
2280  *   CPU1                CPU2
2281  *   sys_select          receive packet
2282  *   ...                 ...
2283  *   __add_wait_queue    update tp->rcv_nxt
2284  *   ...                 ...
2285  *   tp->rcv_nxt check   sock_def_readable
2286  *   ...                 {
2287  *   schedule               rcu_read_lock();
2288  *                          wq = rcu_dereference(sk->sk_wq);
2289  *                          if (wq && waitqueue_active(&wq->wait))
2290  *                              wake_up_interruptible(&wq->wait)
2291  *                          ...
2292  *                       }
2293  *
2294  * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2295  * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
2296  * could then endup calling schedule and sleep forever if there are no more
2297  * data on the socket.
2298  *
2299  */
skwq_has_sleeper(struct socket_wq * wq)2300 static inline bool skwq_has_sleeper(struct socket_wq *wq)
2301 {
2302 	return wq && wq_has_sleeper(&wq->wait);
2303 }
2304 
2305 /**
2306  * sock_poll_wait - place memory barrier behind the poll_wait call.
2307  * @filp:           file
2308  * @sock:           socket to wait on
2309  * @p:              poll_table
2310  *
2311  * See the comments in the wq_has_sleeper function.
2312  */
sock_poll_wait(struct file * filp,struct socket * sock,poll_table * p)2313 static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2314 				  poll_table *p)
2315 {
2316 	if (!poll_does_not_wait(p)) {
2317 		poll_wait(filp, &sock->wq.wait, p);
2318 		/* We need to be sure we are in sync with the
2319 		 * socket flags modification.
2320 		 *
2321 		 * This memory barrier is paired in the wq_has_sleeper.
2322 		 */
2323 		smp_mb();
2324 	}
2325 }
2326 
skb_set_hash_from_sk(struct sk_buff * skb,struct sock * sk)2327 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2328 {
2329 	/* This pairs with WRITE_ONCE() in sk_set_txhash() */
2330 	u32 txhash = READ_ONCE(sk->sk_txhash);
2331 
2332 	if (txhash) {
2333 		skb->l4_hash = 1;
2334 		skb->hash = txhash;
2335 	}
2336 }
2337 
2338 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2339 
2340 /*
2341  *	Queue a received datagram if it will fit. Stream and sequenced
2342  *	protocols can't normally use this as they need to fit buffers in
2343  *	and play with them.
2344  *
2345  *	Inlined as it's very short and called for pretty much every
2346  *	packet ever received.
2347  */
skb_set_owner_r(struct sk_buff * skb,struct sock * sk)2348 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2349 {
2350 	skb_orphan(skb);
2351 	skb->sk = sk;
2352 	skb->destructor = sock_rfree;
2353 	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2354 	sk_mem_charge(sk, skb->truesize);
2355 }
2356 
skb_set_owner_sk_safe(struct sk_buff * skb,struct sock * sk)2357 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2358 {
2359 	if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2360 		skb_orphan(skb);
2361 		skb->destructor = sock_efree;
2362 		skb->sk = sk;
2363 		return true;
2364 	}
2365 	return false;
2366 }
2367 
skb_clone_and_charge_r(struct sk_buff * skb,struct sock * sk)2368 static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk)
2369 {
2370 	skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC));
2371 	if (skb) {
2372 		if (sk_rmem_schedule(sk, skb, skb->truesize)) {
2373 			skb_set_owner_r(skb, sk);
2374 			return skb;
2375 		}
2376 		__kfree_skb(skb);
2377 	}
2378 	return NULL;
2379 }
2380 
skb_prepare_for_gro(struct sk_buff * skb)2381 static inline void skb_prepare_for_gro(struct sk_buff *skb)
2382 {
2383 	if (skb->destructor != sock_wfree) {
2384 		skb_orphan(skb);
2385 		return;
2386 	}
2387 	skb->slow_gro = 1;
2388 }
2389 
2390 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2391 		    unsigned long expires);
2392 
2393 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2394 
2395 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2396 
2397 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2398 			struct sk_buff *skb, unsigned int flags,
2399 			void (*destructor)(struct sock *sk,
2400 					   struct sk_buff *skb));
2401 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2402 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2403 
2404 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2405 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2406 
2407 /*
2408  *	Recover an error report and clear atomically
2409  */
2410 
sock_error(struct sock * sk)2411 static inline int sock_error(struct sock *sk)
2412 {
2413 	int err;
2414 
2415 	/* Avoid an atomic operation for the common case.
2416 	 * This is racy since another cpu/thread can change sk_err under us.
2417 	 */
2418 	if (likely(data_race(!sk->sk_err)))
2419 		return 0;
2420 
2421 	err = xchg(&sk->sk_err, 0);
2422 	return -err;
2423 }
2424 
2425 void sk_error_report(struct sock *sk);
2426 
sock_wspace(struct sock * sk)2427 static inline unsigned long sock_wspace(struct sock *sk)
2428 {
2429 	int amt = 0;
2430 
2431 	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2432 		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2433 		if (amt < 0)
2434 			amt = 0;
2435 	}
2436 	return amt;
2437 }
2438 
2439 /* Note:
2440  *  We use sk->sk_wq_raw, from contexts knowing this
2441  *  pointer is not NULL and cannot disappear/change.
2442  */
sk_set_bit(int nr,struct sock * sk)2443 static inline void sk_set_bit(int nr, struct sock *sk)
2444 {
2445 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2446 	    !sock_flag(sk, SOCK_FASYNC))
2447 		return;
2448 
2449 	set_bit(nr, &sk->sk_wq_raw->flags);
2450 }
2451 
sk_clear_bit(int nr,struct sock * sk)2452 static inline void sk_clear_bit(int nr, struct sock *sk)
2453 {
2454 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2455 	    !sock_flag(sk, SOCK_FASYNC))
2456 		return;
2457 
2458 	clear_bit(nr, &sk->sk_wq_raw->flags);
2459 }
2460 
sk_wake_async(const struct sock * sk,int how,int band)2461 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2462 {
2463 	if (sock_flag(sk, SOCK_FASYNC)) {
2464 		rcu_read_lock();
2465 		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2466 		rcu_read_unlock();
2467 	}
2468 }
2469 
2470 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2471  * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2472  * Note: for send buffers, TCP works better if we can build two skbs at
2473  * minimum.
2474  */
2475 #define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2476 
2477 #define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2478 #define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2479 
sk_stream_moderate_sndbuf(struct sock * sk)2480 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2481 {
2482 	u32 val;
2483 
2484 	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2485 		return;
2486 
2487 	val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2488 
2489 	WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2490 }
2491 
2492 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2493 				    bool force_schedule);
2494 
2495 /**
2496  * sk_page_frag - return an appropriate page_frag
2497  * @sk: socket
2498  *
2499  * Use the per task page_frag instead of the per socket one for
2500  * optimization when we know that we're in process context and own
2501  * everything that's associated with %current.
2502  *
2503  * Both direct reclaim and page faults can nest inside other
2504  * socket operations and end up recursing into sk_page_frag()
2505  * while it's already in use: explicitly avoid task page_frag
2506  * usage if the caller is potentially doing any of them.
2507  * This assumes that page fault handlers use the GFP_NOFS flags.
2508  *
2509  * Return: a per task page_frag if context allows that,
2510  * otherwise a per socket one.
2511  */
sk_page_frag(struct sock * sk)2512 static inline struct page_frag *sk_page_frag(struct sock *sk)
2513 {
2514 	if ((sk->sk_allocation & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC | __GFP_FS)) ==
2515 	    (__GFP_DIRECT_RECLAIM | __GFP_FS))
2516 		return &current->task_frag;
2517 
2518 	return &sk->sk_frag;
2519 }
2520 
2521 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2522 
2523 /*
2524  *	Default write policy as shown to user space via poll/select/SIGIO
2525  */
sock_writeable(const struct sock * sk)2526 static inline bool sock_writeable(const struct sock *sk)
2527 {
2528 	return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2529 }
2530 
gfp_any(void)2531 static inline gfp_t gfp_any(void)
2532 {
2533 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2534 }
2535 
gfp_memcg_charge(void)2536 static inline gfp_t gfp_memcg_charge(void)
2537 {
2538 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2539 }
2540 
sock_rcvtimeo(const struct sock * sk,bool noblock)2541 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2542 {
2543 	return noblock ? 0 : sk->sk_rcvtimeo;
2544 }
2545 
sock_sndtimeo(const struct sock * sk,bool noblock)2546 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2547 {
2548 	return noblock ? 0 : sk->sk_sndtimeo;
2549 }
2550 
sock_rcvlowat(const struct sock * sk,int waitall,int len)2551 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2552 {
2553 	int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2554 
2555 	return v ?: 1;
2556 }
2557 
2558 /* Alas, with timeout socket operations are not restartable.
2559  * Compare this to poll().
2560  */
sock_intr_errno(long timeo)2561 static inline int sock_intr_errno(long timeo)
2562 {
2563 	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2564 }
2565 
2566 struct sock_skb_cb {
2567 	u32 dropcount;
2568 };
2569 
2570 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2571  * using skb->cb[] would keep using it directly and utilize its
2572  * alignement guarantee.
2573  */
2574 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2575 			    sizeof(struct sock_skb_cb)))
2576 
2577 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2578 			    SOCK_SKB_CB_OFFSET))
2579 
2580 #define sock_skb_cb_check_size(size) \
2581 	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2582 
2583 static inline void
sock_skb_set_dropcount(const struct sock * sk,struct sk_buff * skb)2584 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2585 {
2586 	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2587 						atomic_read(&sk->sk_drops) : 0;
2588 }
2589 
sk_drops_add(struct sock * sk,const struct sk_buff * skb)2590 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2591 {
2592 	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2593 
2594 	atomic_add(segs, &sk->sk_drops);
2595 }
2596 
sock_read_timestamp(struct sock * sk)2597 static inline ktime_t sock_read_timestamp(struct sock *sk)
2598 {
2599 #if BITS_PER_LONG==32
2600 	unsigned int seq;
2601 	ktime_t kt;
2602 
2603 	do {
2604 		seq = read_seqbegin(&sk->sk_stamp_seq);
2605 		kt = sk->sk_stamp;
2606 	} while (read_seqretry(&sk->sk_stamp_seq, seq));
2607 
2608 	return kt;
2609 #else
2610 	return READ_ONCE(sk->sk_stamp);
2611 #endif
2612 }
2613 
sock_write_timestamp(struct sock * sk,ktime_t kt)2614 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2615 {
2616 #if BITS_PER_LONG==32
2617 	write_seqlock(&sk->sk_stamp_seq);
2618 	sk->sk_stamp = kt;
2619 	write_sequnlock(&sk->sk_stamp_seq);
2620 #else
2621 	WRITE_ONCE(sk->sk_stamp, kt);
2622 #endif
2623 }
2624 
2625 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2626 			   struct sk_buff *skb);
2627 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2628 			     struct sk_buff *skb);
2629 
2630 static inline void
sock_recv_timestamp(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2631 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2632 {
2633 	ktime_t kt = skb->tstamp;
2634 	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2635 
2636 	/*
2637 	 * generate control messages if
2638 	 * - receive time stamping in software requested
2639 	 * - software time stamp available and wanted
2640 	 * - hardware time stamps available and wanted
2641 	 */
2642 	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2643 	    (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2644 	    (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2645 	    (hwtstamps->hwtstamp &&
2646 	     (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2647 		__sock_recv_timestamp(msg, sk, skb);
2648 	else
2649 		sock_write_timestamp(sk, kt);
2650 
2651 	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2652 		__sock_recv_wifi_status(msg, sk, skb);
2653 }
2654 
2655 void __sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2656 		       struct sk_buff *skb);
2657 
2658 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
sock_recv_cmsgs(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2659 static inline void sock_recv_cmsgs(struct msghdr *msg, struct sock *sk,
2660 				   struct sk_buff *skb)
2661 {
2662 #define FLAGS_RECV_CMSGS ((1UL << SOCK_RXQ_OVFL)			| \
2663 			   (1UL << SOCK_RCVTSTAMP)			| \
2664 			   (1UL << SOCK_RCVMARK))
2665 #define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
2666 			   SOF_TIMESTAMPING_RAW_HARDWARE)
2667 
2668 	if (sk->sk_flags & FLAGS_RECV_CMSGS || sk->sk_tsflags & TSFLAGS_ANY)
2669 		__sock_recv_cmsgs(msg, sk, skb);
2670 	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2671 		sock_write_timestamp(sk, skb->tstamp);
2672 	else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP))
2673 		sock_write_timestamp(sk, 0);
2674 }
2675 
2676 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2677 
2678 /**
2679  * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2680  * @sk:		socket sending this packet
2681  * @tsflags:	timestamping flags to use
2682  * @tx_flags:	completed with instructions for time stamping
2683  * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
2684  *
2685  * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2686  */
_sock_tx_timestamp(struct sock * sk,__u16 tsflags,__u8 * tx_flags,__u32 * tskey)2687 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2688 				      __u8 *tx_flags, __u32 *tskey)
2689 {
2690 	if (unlikely(tsflags)) {
2691 		__sock_tx_timestamp(tsflags, tx_flags);
2692 		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2693 		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2694 			*tskey = atomic_inc_return(&sk->sk_tskey) - 1;
2695 	}
2696 	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2697 		*tx_flags |= SKBTX_WIFI_STATUS;
2698 }
2699 
sock_tx_timestamp(struct sock * sk,__u16 tsflags,__u8 * tx_flags)2700 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2701 				     __u8 *tx_flags)
2702 {
2703 	_sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2704 }
2705 
skb_setup_tx_timestamp(struct sk_buff * skb,__u16 tsflags)2706 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2707 {
2708 	_sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2709 			   &skb_shinfo(skb)->tskey);
2710 }
2711 
2712 DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key);
2713 /**
2714  * sk_eat_skb - Release a skb if it is no longer needed
2715  * @sk: socket to eat this skb from
2716  * @skb: socket buffer to eat
2717  *
2718  * This routine must be called with interrupts disabled or with the socket
2719  * locked so that the sk_buff queue operation is ok.
2720 */
sk_eat_skb(struct sock * sk,struct sk_buff * skb)2721 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2722 {
2723 	__skb_unlink(skb, &sk->sk_receive_queue);
2724 	if (static_branch_unlikely(&tcp_rx_skb_cache_key) &&
2725 	    !sk->sk_rx_skb_cache) {
2726 		sk->sk_rx_skb_cache = skb;
2727 		skb_orphan(skb);
2728 		return;
2729 	}
2730 	__kfree_skb(skb);
2731 }
2732 
2733 static inline
sock_net(const struct sock * sk)2734 struct net *sock_net(const struct sock *sk)
2735 {
2736 	return read_pnet(&sk->sk_net);
2737 }
2738 
2739 static inline
sock_net_set(struct sock * sk,struct net * net)2740 void sock_net_set(struct sock *sk, struct net *net)
2741 {
2742 	write_pnet(&sk->sk_net, net);
2743 }
2744 
2745 static inline bool
skb_sk_is_prefetched(struct sk_buff * skb)2746 skb_sk_is_prefetched(struct sk_buff *skb)
2747 {
2748 #ifdef CONFIG_INET
2749 	return skb->destructor == sock_pfree;
2750 #else
2751 	return false;
2752 #endif /* CONFIG_INET */
2753 }
2754 
2755 /* This helper checks if a socket is a full socket,
2756  * ie _not_ a timewait or request socket.
2757  */
sk_fullsock(const struct sock * sk)2758 static inline bool sk_fullsock(const struct sock *sk)
2759 {
2760 	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2761 }
2762 
2763 static inline bool
sk_is_refcounted(struct sock * sk)2764 sk_is_refcounted(struct sock *sk)
2765 {
2766 	/* Only full sockets have sk->sk_flags. */
2767 	return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2768 }
2769 
2770 /**
2771  * skb_steal_sock - steal a socket from an sk_buff
2772  * @skb: sk_buff to steal the socket from
2773  * @refcounted: is set to true if the socket is reference-counted
2774  */
2775 static inline struct sock *
skb_steal_sock(struct sk_buff * skb,bool * refcounted)2776 skb_steal_sock(struct sk_buff *skb, bool *refcounted)
2777 {
2778 	if (skb->sk) {
2779 		struct sock *sk = skb->sk;
2780 
2781 		*refcounted = true;
2782 		if (skb_sk_is_prefetched(skb))
2783 			*refcounted = sk_is_refcounted(sk);
2784 		skb->destructor = NULL;
2785 		skb->sk = NULL;
2786 		return sk;
2787 	}
2788 	*refcounted = false;
2789 	return NULL;
2790 }
2791 
2792 /* Checks if this SKB belongs to an HW offloaded socket
2793  * and whether any SW fallbacks are required based on dev.
2794  * Check decrypted mark in case skb_orphan() cleared socket.
2795  */
sk_validate_xmit_skb(struct sk_buff * skb,struct net_device * dev)2796 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2797 						   struct net_device *dev)
2798 {
2799 #ifdef CONFIG_SOCK_VALIDATE_XMIT
2800 	struct sock *sk = skb->sk;
2801 
2802 	if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2803 		skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2804 #ifdef CONFIG_TLS_DEVICE
2805 	} else if (unlikely(skb->decrypted)) {
2806 		pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2807 		kfree_skb(skb);
2808 		skb = NULL;
2809 #endif
2810 	}
2811 #endif
2812 
2813 	return skb;
2814 }
2815 
2816 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2817  * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2818  */
sk_listener(const struct sock * sk)2819 static inline bool sk_listener(const struct sock *sk)
2820 {
2821 	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2822 }
2823 
2824 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2825 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2826 		       int type);
2827 
2828 bool sk_ns_capable(const struct sock *sk,
2829 		   struct user_namespace *user_ns, int cap);
2830 bool sk_capable(const struct sock *sk, int cap);
2831 bool sk_net_capable(const struct sock *sk, int cap);
2832 
2833 void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2834 
2835 /* Take into consideration the size of the struct sk_buff overhead in the
2836  * determination of these values, since that is non-constant across
2837  * platforms.  This makes socket queueing behavior and performance
2838  * not depend upon such differences.
2839  */
2840 #define _SK_MEM_PACKETS		256
2841 #define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
2842 #define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2843 #define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2844 
2845 extern __u32 sysctl_wmem_max;
2846 extern __u32 sysctl_rmem_max;
2847 
2848 extern int sysctl_tstamp_allow_data;
2849 extern int sysctl_optmem_max;
2850 
2851 extern __u32 sysctl_wmem_default;
2852 extern __u32 sysctl_rmem_default;
2853 
2854 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2855 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2856 
sk_get_wmem0(const struct sock * sk,const struct proto * proto)2857 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2858 {
2859 	/* Does this proto have per netns sysctl_wmem ? */
2860 	if (proto->sysctl_wmem_offset)
2861 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2862 
2863 	return READ_ONCE(*proto->sysctl_wmem);
2864 }
2865 
sk_get_rmem0(const struct sock * sk,const struct proto * proto)2866 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2867 {
2868 	/* Does this proto have per netns sysctl_rmem ? */
2869 	if (proto->sysctl_rmem_offset)
2870 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2871 
2872 	return READ_ONCE(*proto->sysctl_rmem);
2873 }
2874 
2875 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2876  * Some wifi drivers need to tweak it to get more chunks.
2877  * They can use this helper from their ndo_start_xmit()
2878  */
sk_pacing_shift_update(struct sock * sk,int val)2879 static inline void sk_pacing_shift_update(struct sock *sk, int val)
2880 {
2881 	if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2882 		return;
2883 	WRITE_ONCE(sk->sk_pacing_shift, val);
2884 }
2885 
2886 /* if a socket is bound to a device, check that the given device
2887  * index is either the same or that the socket is bound to an L3
2888  * master device and the given device index is also enslaved to
2889  * that L3 master
2890  */
sk_dev_equal_l3scope(struct sock * sk,int dif)2891 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2892 {
2893 	int mdif;
2894 
2895 	if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
2896 		return true;
2897 
2898 	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2899 	if (mdif && mdif == sk->sk_bound_dev_if)
2900 		return true;
2901 
2902 	return false;
2903 }
2904 
2905 void sock_def_readable(struct sock *sk);
2906 
2907 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2908 void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2909 int sock_set_timestamping(struct sock *sk, int optname,
2910 			  struct so_timestamping timestamping);
2911 
2912 void sock_enable_timestamps(struct sock *sk);
2913 void sock_no_linger(struct sock *sk);
2914 void sock_set_keepalive(struct sock *sk);
2915 void sock_set_priority(struct sock *sk, u32 priority);
2916 void sock_set_rcvbuf(struct sock *sk, int val);
2917 void sock_set_mark(struct sock *sk, u32 val);
2918 void sock_set_reuseaddr(struct sock *sk);
2919 void sock_set_reuseport(struct sock *sk);
2920 void sock_set_sndtimeo(struct sock *sk, s64 secs);
2921 
2922 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2923 
sk_is_readable(struct sock * sk)2924 static inline bool sk_is_readable(struct sock *sk)
2925 {
2926 	if (sk->sk_prot->sock_is_readable)
2927 		return sk->sk_prot->sock_is_readable(sk);
2928 	return false;
2929 }
2930 #endif	/* _SOCK_H */
2931