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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_state_change: callback to indicate change in the state of the sock
340   *	@sk_data_ready: callback to indicate there is data to be processed
341   *	@sk_write_space: callback to indicate there is bf sending space available
342   *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
343   *	@sk_backlog_rcv: callback to process the backlog
344   *	@sk_validate_xmit_skb: ptr to an optional validate function
345   *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
346   *	@sk_reuseport_cb: reuseport group container
347   *	@sk_bpf_storage: ptr to cache and control for bpf_sk_storage
348   *	@sk_rcu: used during RCU grace period
349   *	@sk_clockid: clockid used by time-based scheduling (SO_TXTIME)
350   *	@sk_txtime_deadline_mode: set deadline mode for SO_TXTIME
351   *	@sk_txtime_report_errors: set report errors mode for SO_TXTIME
352   *	@sk_txtime_unused: unused txtime flags
353   */
354 struct sock {
355 	/*
356 	 * Now struct inet_timewait_sock also uses sock_common, so please just
357 	 * don't add nothing before this first member (__sk_common) --acme
358 	 */
359 	struct sock_common	__sk_common;
360 #define sk_node			__sk_common.skc_node
361 #define sk_nulls_node		__sk_common.skc_nulls_node
362 #define sk_refcnt		__sk_common.skc_refcnt
363 #define sk_tx_queue_mapping	__sk_common.skc_tx_queue_mapping
364 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
365 #define sk_rx_queue_mapping	__sk_common.skc_rx_queue_mapping
366 #endif
367 
368 #define sk_dontcopy_begin	__sk_common.skc_dontcopy_begin
369 #define sk_dontcopy_end		__sk_common.skc_dontcopy_end
370 #define sk_hash			__sk_common.skc_hash
371 #define sk_portpair		__sk_common.skc_portpair
372 #define sk_num			__sk_common.skc_num
373 #define sk_dport		__sk_common.skc_dport
374 #define sk_addrpair		__sk_common.skc_addrpair
375 #define sk_daddr		__sk_common.skc_daddr
376 #define sk_rcv_saddr		__sk_common.skc_rcv_saddr
377 #define sk_family		__sk_common.skc_family
378 #define sk_state		__sk_common.skc_state
379 #define sk_reuse		__sk_common.skc_reuse
380 #define sk_reuseport		__sk_common.skc_reuseport
381 #define sk_ipv6only		__sk_common.skc_ipv6only
382 #define sk_net_refcnt		__sk_common.skc_net_refcnt
383 #define sk_bound_dev_if		__sk_common.skc_bound_dev_if
384 #define sk_bind_node		__sk_common.skc_bind_node
385 #define sk_prot			__sk_common.skc_prot
386 #define sk_net			__sk_common.skc_net
387 #define sk_v6_daddr		__sk_common.skc_v6_daddr
388 #define sk_v6_rcv_saddr	__sk_common.skc_v6_rcv_saddr
389 #define sk_cookie		__sk_common.skc_cookie
390 #define sk_incoming_cpu		__sk_common.skc_incoming_cpu
391 #define sk_flags		__sk_common.skc_flags
392 #define sk_rxhash		__sk_common.skc_rxhash
393 
394 	socket_lock_t		sk_lock;
395 	atomic_t		sk_drops;
396 	int			sk_rcvlowat;
397 	struct sk_buff_head	sk_error_queue;
398 	struct sk_buff		*sk_rx_skb_cache;
399 	struct sk_buff_head	sk_receive_queue;
400 	/*
401 	 * The backlog queue is special, it is always used with
402 	 * the per-socket spinlock held and requires low latency
403 	 * access. Therefore we special case it's implementation.
404 	 * Note : rmem_alloc is in this structure to fill a hole
405 	 * on 64bit arches, not because its logically part of
406 	 * backlog.
407 	 */
408 	struct {
409 		atomic_t	rmem_alloc;
410 		int		len;
411 		struct sk_buff	*head;
412 		struct sk_buff	*tail;
413 	} sk_backlog;
414 #define sk_rmem_alloc sk_backlog.rmem_alloc
415 
416 	int			sk_forward_alloc;
417 #ifdef CONFIG_NET_RX_BUSY_POLL
418 	unsigned int		sk_ll_usec;
419 	/* ===== mostly read cache line ===== */
420 	unsigned int		sk_napi_id;
421 #endif
422 	int			sk_rcvbuf;
423 
424 	struct sk_filter __rcu	*sk_filter;
425 	union {
426 		struct socket_wq __rcu	*sk_wq;
427 		/* private: */
428 		struct socket_wq	*sk_wq_raw;
429 		/* public: */
430 	};
431 #ifdef CONFIG_XFRM
432 	struct xfrm_policy __rcu *sk_policy[2];
433 #endif
434 	struct dst_entry __rcu	*sk_rx_dst;
435 	int			sk_rx_dst_ifindex;
436 	u32			sk_rx_dst_cookie;
437 
438 	struct dst_entry __rcu	*sk_dst_cache;
439 	atomic_t		sk_omem_alloc;
440 	int			sk_sndbuf;
441 
442 	/* ===== cache line for TX ===== */
443 	int			sk_wmem_queued;
444 	refcount_t		sk_wmem_alloc;
445 	unsigned long		sk_tsq_flags;
446 	union {
447 		struct sk_buff	*sk_send_head;
448 		struct rb_root	tcp_rtx_queue;
449 	};
450 	struct sk_buff		*sk_tx_skb_cache;
451 	struct sk_buff_head	sk_write_queue;
452 	__s32			sk_peek_off;
453 	int			sk_write_pending;
454 	__u32			sk_dst_pending_confirm;
455 	u32			sk_pacing_status; /* see enum sk_pacing */
456 	long			sk_sndtimeo;
457 	struct timer_list	sk_timer;
458 	__u32			sk_priority;
459 	__u32			sk_mark;
460 	unsigned long		sk_pacing_rate; /* bytes per second */
461 	unsigned long		sk_max_pacing_rate;
462 	struct page_frag	sk_frag;
463 	netdev_features_t	sk_route_caps;
464 	netdev_features_t	sk_route_nocaps;
465 	netdev_features_t	sk_route_forced_caps;
466 	int			sk_gso_type;
467 	unsigned int		sk_gso_max_size;
468 	gfp_t			sk_allocation;
469 	__u32			sk_txhash;
470 
471 	/*
472 	 * Because of non atomicity rules, all
473 	 * changes are protected by socket lock.
474 	 */
475 	u8			sk_padding : 1,
476 				sk_kern_sock : 1,
477 				sk_no_check_tx : 1,
478 				sk_no_check_rx : 1,
479 				sk_userlocks : 4;
480 	u8			sk_pacing_shift;
481 	u16			sk_type;
482 	u16			sk_protocol;
483 	u16			sk_gso_max_segs;
484 	unsigned long	        sk_lingertime;
485 	struct proto		*sk_prot_creator;
486 	rwlock_t		sk_callback_lock;
487 	int			sk_err,
488 				sk_err_soft;
489 	u32			sk_ack_backlog;
490 	u32			sk_max_ack_backlog;
491 	kuid_t			sk_uid;
492 #ifdef CONFIG_NET_RX_BUSY_POLL
493 	u8			sk_prefer_busy_poll;
494 	u16			sk_busy_poll_budget;
495 #endif
496 	spinlock_t		sk_peer_lock;
497 	struct pid		*sk_peer_pid;
498 	const struct cred	*sk_peer_cred;
499 
500 	long			sk_rcvtimeo;
501 	ktime_t			sk_stamp;
502 #if BITS_PER_LONG==32
503 	seqlock_t		sk_stamp_seq;
504 #endif
505 	u16			sk_tsflags;
506 	int			sk_bind_phc;
507 	u8			sk_shutdown;
508 	atomic_t		sk_tskey;
509 	atomic_t		sk_zckey;
510 
511 	u8			sk_clockid;
512 	u8			sk_txtime_deadline_mode : 1,
513 				sk_txtime_report_errors : 1,
514 				sk_txtime_unused : 6;
515 
516 	struct socket		*sk_socket;
517 	void			*sk_user_data;
518 #ifdef CONFIG_SECURITY
519 	void			*sk_security;
520 #endif
521 	struct sock_cgroup_data	sk_cgrp_data;
522 	struct mem_cgroup	*sk_memcg;
523 	void			(*sk_state_change)(struct sock *sk);
524 	void			(*sk_data_ready)(struct sock *sk);
525 	void			(*sk_write_space)(struct sock *sk);
526 	void			(*sk_error_report)(struct sock *sk);
527 	int			(*sk_backlog_rcv)(struct sock *sk,
528 						  struct sk_buff *skb);
529 #ifdef CONFIG_SOCK_VALIDATE_XMIT
530 	struct sk_buff*		(*sk_validate_xmit_skb)(struct sock *sk,
531 							struct net_device *dev,
532 							struct sk_buff *skb);
533 #endif
534 	void                    (*sk_destruct)(struct sock *sk);
535 	struct sock_reuseport __rcu	*sk_reuseport_cb;
536 #ifdef CONFIG_BPF_SYSCALL
537 	struct bpf_local_storage __rcu	*sk_bpf_storage;
538 #endif
539 	struct rcu_head		sk_rcu;
540 
541 	ANDROID_OEM_DATA(1);
542 	ANDROID_KABI_RESERVE(1);
543 	ANDROID_KABI_RESERVE(2);
544 	ANDROID_KABI_RESERVE(3);
545 	ANDROID_KABI_RESERVE(4);
546 	ANDROID_KABI_RESERVE(5);
547 	ANDROID_KABI_RESERVE(6);
548 	ANDROID_KABI_RESERVE(7);
549 	ANDROID_KABI_RESERVE(8);
550 };
551 
552 enum sk_pacing {
553 	SK_PACING_NONE		= 0,
554 	SK_PACING_NEEDED	= 1,
555 	SK_PACING_FQ		= 2,
556 };
557 
558 /* flag bits in sk_user_data
559  *
560  * - SK_USER_DATA_NOCOPY:      Pointer stored in sk_user_data might
561  *   not be suitable for copying when cloning the socket. For instance,
562  *   it can point to a reference counted object. sk_user_data bottom
563  *   bit is set if pointer must not be copied.
564  *
565  * - SK_USER_DATA_BPF:         Mark whether sk_user_data field is
566  *   managed/owned by a BPF reuseport array. This bit should be set
567  *   when sk_user_data's sk is added to the bpf's reuseport_array.
568  *
569  * - SK_USER_DATA_PSOCK:       Mark whether pointer stored in
570  *   sk_user_data points to psock type. This bit should be set
571  *   when sk_user_data is assigned to a psock object.
572  */
573 #define SK_USER_DATA_NOCOPY	1UL
574 #define SK_USER_DATA_BPF	2UL
575 #define SK_USER_DATA_PSOCK	4UL
576 #define SK_USER_DATA_PTRMASK	~(SK_USER_DATA_NOCOPY | SK_USER_DATA_BPF |\
577 				  SK_USER_DATA_PSOCK)
578 
579 /**
580  * sk_user_data_is_nocopy - Test if sk_user_data pointer must not be copied
581  * @sk: socket
582  */
sk_user_data_is_nocopy(const struct sock * sk)583 static inline bool sk_user_data_is_nocopy(const struct sock *sk)
584 {
585 	return ((uintptr_t)sk->sk_user_data & SK_USER_DATA_NOCOPY);
586 }
587 
588 #define __sk_user_data(sk) ((*((void __rcu **)&(sk)->sk_user_data)))
589 
590 /**
591  * __rcu_dereference_sk_user_data_with_flags - return the pointer
592  * only if argument flags all has been set in sk_user_data. Otherwise
593  * return NULL
594  *
595  * @sk: socket
596  * @flags: flag bits
597  */
598 static inline void *
__rcu_dereference_sk_user_data_with_flags(const struct sock * sk,uintptr_t flags)599 __rcu_dereference_sk_user_data_with_flags(const struct sock *sk,
600 					  uintptr_t flags)
601 {
602 	uintptr_t sk_user_data = (uintptr_t)rcu_dereference(__sk_user_data(sk));
603 
604 	WARN_ON_ONCE(flags & SK_USER_DATA_PTRMASK);
605 
606 	if ((sk_user_data & flags) == flags)
607 		return (void *)(sk_user_data & SK_USER_DATA_PTRMASK);
608 	return NULL;
609 }
610 
611 #define rcu_dereference_sk_user_data(sk)				\
612 	__rcu_dereference_sk_user_data_with_flags(sk, 0)
613 #define __rcu_assign_sk_user_data_with_flags(sk, ptr, flags)		\
614 ({									\
615 	uintptr_t __tmp1 = (uintptr_t)(ptr),				\
616 		  __tmp2 = (uintptr_t)(flags);				\
617 	WARN_ON_ONCE(__tmp1 & ~SK_USER_DATA_PTRMASK);			\
618 	WARN_ON_ONCE(__tmp2 & SK_USER_DATA_PTRMASK);			\
619 	rcu_assign_pointer(__sk_user_data((sk)),			\
620 			   __tmp1 | __tmp2);				\
621 })
622 #define rcu_assign_sk_user_data(sk, ptr)				\
623 	__rcu_assign_sk_user_data_with_flags(sk, ptr, 0)
624 
625 /*
626  * SK_CAN_REUSE and SK_NO_REUSE on a socket mean that the socket is OK
627  * or not whether his port will be reused by someone else. SK_FORCE_REUSE
628  * on a socket means that the socket will reuse everybody else's port
629  * without looking at the other's sk_reuse value.
630  */
631 
632 #define SK_NO_REUSE	0
633 #define SK_CAN_REUSE	1
634 #define SK_FORCE_REUSE	2
635 
636 int sk_set_peek_off(struct sock *sk, int val);
637 
sk_peek_offset(struct sock * sk,int flags)638 static inline int sk_peek_offset(struct sock *sk, int flags)
639 {
640 	if (unlikely(flags & MSG_PEEK)) {
641 		return READ_ONCE(sk->sk_peek_off);
642 	}
643 
644 	return 0;
645 }
646 
sk_peek_offset_bwd(struct sock * sk,int val)647 static inline void sk_peek_offset_bwd(struct sock *sk, int val)
648 {
649 	s32 off = READ_ONCE(sk->sk_peek_off);
650 
651 	if (unlikely(off >= 0)) {
652 		off = max_t(s32, off - val, 0);
653 		WRITE_ONCE(sk->sk_peek_off, off);
654 	}
655 }
656 
sk_peek_offset_fwd(struct sock * sk,int val)657 static inline void sk_peek_offset_fwd(struct sock *sk, int val)
658 {
659 	sk_peek_offset_bwd(sk, -val);
660 }
661 
662 /*
663  * Hashed lists helper routines
664  */
sk_entry(const struct hlist_node * node)665 static inline struct sock *sk_entry(const struct hlist_node *node)
666 {
667 	return hlist_entry(node, struct sock, sk_node);
668 }
669 
__sk_head(const struct hlist_head * head)670 static inline struct sock *__sk_head(const struct hlist_head *head)
671 {
672 	return hlist_entry(head->first, struct sock, sk_node);
673 }
674 
sk_head(const struct hlist_head * head)675 static inline struct sock *sk_head(const struct hlist_head *head)
676 {
677 	return hlist_empty(head) ? NULL : __sk_head(head);
678 }
679 
__sk_nulls_head(const struct hlist_nulls_head * head)680 static inline struct sock *__sk_nulls_head(const struct hlist_nulls_head *head)
681 {
682 	return hlist_nulls_entry(head->first, struct sock, sk_nulls_node);
683 }
684 
sk_nulls_head(const struct hlist_nulls_head * head)685 static inline struct sock *sk_nulls_head(const struct hlist_nulls_head *head)
686 {
687 	return hlist_nulls_empty(head) ? NULL : __sk_nulls_head(head);
688 }
689 
sk_next(const struct sock * sk)690 static inline struct sock *sk_next(const struct sock *sk)
691 {
692 	return hlist_entry_safe(sk->sk_node.next, struct sock, sk_node);
693 }
694 
sk_nulls_next(const struct sock * sk)695 static inline struct sock *sk_nulls_next(const struct sock *sk)
696 {
697 	return (!is_a_nulls(sk->sk_nulls_node.next)) ?
698 		hlist_nulls_entry(sk->sk_nulls_node.next,
699 				  struct sock, sk_nulls_node) :
700 		NULL;
701 }
702 
sk_unhashed(const struct sock * sk)703 static inline bool sk_unhashed(const struct sock *sk)
704 {
705 	return hlist_unhashed(&sk->sk_node);
706 }
707 
sk_hashed(const struct sock * sk)708 static inline bool sk_hashed(const struct sock *sk)
709 {
710 	return !sk_unhashed(sk);
711 }
712 
sk_node_init(struct hlist_node * node)713 static inline void sk_node_init(struct hlist_node *node)
714 {
715 	node->pprev = NULL;
716 }
717 
sk_nulls_node_init(struct hlist_nulls_node * node)718 static inline void sk_nulls_node_init(struct hlist_nulls_node *node)
719 {
720 	node->pprev = NULL;
721 }
722 
__sk_del_node(struct sock * sk)723 static inline void __sk_del_node(struct sock *sk)
724 {
725 	__hlist_del(&sk->sk_node);
726 }
727 
728 /* NB: equivalent to hlist_del_init_rcu */
__sk_del_node_init(struct sock * sk)729 static inline bool __sk_del_node_init(struct sock *sk)
730 {
731 	if (sk_hashed(sk)) {
732 		__sk_del_node(sk);
733 		sk_node_init(&sk->sk_node);
734 		return true;
735 	}
736 	return false;
737 }
738 
739 /* Grab socket reference count. This operation is valid only
740    when sk is ALREADY grabbed f.e. it is found in hash table
741    or a list and the lookup is made under lock preventing hash table
742    modifications.
743  */
744 
sock_hold(struct sock * sk)745 static __always_inline void sock_hold(struct sock *sk)
746 {
747 	refcount_inc(&sk->sk_refcnt);
748 }
749 
750 /* Ungrab socket in the context, which assumes that socket refcnt
751    cannot hit zero, f.e. it is true in context of any socketcall.
752  */
__sock_put(struct sock * sk)753 static __always_inline void __sock_put(struct sock *sk)
754 {
755 	refcount_dec(&sk->sk_refcnt);
756 }
757 
sk_del_node_init(struct sock * sk)758 static inline bool sk_del_node_init(struct sock *sk)
759 {
760 	bool rc = __sk_del_node_init(sk);
761 
762 	if (rc) {
763 		/* paranoid for a while -acme */
764 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
765 		__sock_put(sk);
766 	}
767 	return rc;
768 }
769 #define sk_del_node_init_rcu(sk)	sk_del_node_init(sk)
770 
__sk_nulls_del_node_init_rcu(struct sock * sk)771 static inline bool __sk_nulls_del_node_init_rcu(struct sock *sk)
772 {
773 	if (sk_hashed(sk)) {
774 		hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
775 		return true;
776 	}
777 	return false;
778 }
779 
sk_nulls_del_node_init_rcu(struct sock * sk)780 static inline bool sk_nulls_del_node_init_rcu(struct sock *sk)
781 {
782 	bool rc = __sk_nulls_del_node_init_rcu(sk);
783 
784 	if (rc) {
785 		/* paranoid for a while -acme */
786 		WARN_ON(refcount_read(&sk->sk_refcnt) == 1);
787 		__sock_put(sk);
788 	}
789 	return rc;
790 }
791 
__sk_add_node(struct sock * sk,struct hlist_head * list)792 static inline void __sk_add_node(struct sock *sk, struct hlist_head *list)
793 {
794 	hlist_add_head(&sk->sk_node, list);
795 }
796 
sk_add_node(struct sock * sk,struct hlist_head * list)797 static inline void sk_add_node(struct sock *sk, struct hlist_head *list)
798 {
799 	sock_hold(sk);
800 	__sk_add_node(sk, list);
801 }
802 
sk_add_node_rcu(struct sock * sk,struct hlist_head * list)803 static inline void sk_add_node_rcu(struct sock *sk, struct hlist_head *list)
804 {
805 	sock_hold(sk);
806 	if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
807 	    sk->sk_family == AF_INET6)
808 		hlist_add_tail_rcu(&sk->sk_node, list);
809 	else
810 		hlist_add_head_rcu(&sk->sk_node, list);
811 }
812 
sk_add_node_tail_rcu(struct sock * sk,struct hlist_head * list)813 static inline void sk_add_node_tail_rcu(struct sock *sk, struct hlist_head *list)
814 {
815 	sock_hold(sk);
816 	hlist_add_tail_rcu(&sk->sk_node, list);
817 }
818 
__sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)819 static inline void __sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
820 {
821 	hlist_nulls_add_head_rcu(&sk->sk_nulls_node, list);
822 }
823 
__sk_nulls_add_node_tail_rcu(struct sock * sk,struct hlist_nulls_head * list)824 static inline void __sk_nulls_add_node_tail_rcu(struct sock *sk, struct hlist_nulls_head *list)
825 {
826 	hlist_nulls_add_tail_rcu(&sk->sk_nulls_node, list);
827 }
828 
sk_nulls_add_node_rcu(struct sock * sk,struct hlist_nulls_head * list)829 static inline void sk_nulls_add_node_rcu(struct sock *sk, struct hlist_nulls_head *list)
830 {
831 	sock_hold(sk);
832 	__sk_nulls_add_node_rcu(sk, list);
833 }
834 
__sk_del_bind_node(struct sock * sk)835 static inline void __sk_del_bind_node(struct sock *sk)
836 {
837 	__hlist_del(&sk->sk_bind_node);
838 }
839 
sk_add_bind_node(struct sock * sk,struct hlist_head * list)840 static inline void sk_add_bind_node(struct sock *sk,
841 					struct hlist_head *list)
842 {
843 	hlist_add_head(&sk->sk_bind_node, list);
844 }
845 
846 #define sk_for_each(__sk, list) \
847 	hlist_for_each_entry(__sk, list, sk_node)
848 #define sk_for_each_rcu(__sk, list) \
849 	hlist_for_each_entry_rcu(__sk, list, sk_node)
850 #define sk_nulls_for_each(__sk, node, list) \
851 	hlist_nulls_for_each_entry(__sk, node, list, sk_nulls_node)
852 #define sk_nulls_for_each_rcu(__sk, node, list) \
853 	hlist_nulls_for_each_entry_rcu(__sk, node, list, sk_nulls_node)
854 #define sk_for_each_from(__sk) \
855 	hlist_for_each_entry_from(__sk, sk_node)
856 #define sk_nulls_for_each_from(__sk, node) \
857 	if (__sk && ({ node = &(__sk)->sk_nulls_node; 1; })) \
858 		hlist_nulls_for_each_entry_from(__sk, node, sk_nulls_node)
859 #define sk_for_each_safe(__sk, tmp, list) \
860 	hlist_for_each_entry_safe(__sk, tmp, list, sk_node)
861 #define sk_for_each_bound(__sk, list) \
862 	hlist_for_each_entry(__sk, list, sk_bind_node)
863 
864 /**
865  * sk_for_each_entry_offset_rcu - iterate over a list at a given struct offset
866  * @tpos:	the type * to use as a loop cursor.
867  * @pos:	the &struct hlist_node to use as a loop cursor.
868  * @head:	the head for your list.
869  * @offset:	offset of hlist_node within the struct.
870  *
871  */
872 #define sk_for_each_entry_offset_rcu(tpos, pos, head, offset)		       \
873 	for (pos = rcu_dereference(hlist_first_rcu(head));		       \
874 	     pos != NULL &&						       \
875 		({ tpos = (typeof(*tpos) *)((void *)pos - offset); 1;});       \
876 	     pos = rcu_dereference(hlist_next_rcu(pos)))
877 
sk_user_ns(struct sock * sk)878 static inline struct user_namespace *sk_user_ns(struct sock *sk)
879 {
880 	/* Careful only use this in a context where these parameters
881 	 * can not change and must all be valid, such as recvmsg from
882 	 * userspace.
883 	 */
884 	return sk->sk_socket->file->f_cred->user_ns;
885 }
886 
887 /* Sock flags */
888 enum sock_flags {
889 	SOCK_DEAD,
890 	SOCK_DONE,
891 	SOCK_URGINLINE,
892 	SOCK_KEEPOPEN,
893 	SOCK_LINGER,
894 	SOCK_DESTROY,
895 	SOCK_BROADCAST,
896 	SOCK_TIMESTAMP,
897 	SOCK_ZAPPED,
898 	SOCK_USE_WRITE_QUEUE, /* whether to call sk->sk_write_space in sock_wfree */
899 	SOCK_DBG, /* %SO_DEBUG setting */
900 	SOCK_RCVTSTAMP, /* %SO_TIMESTAMP setting */
901 	SOCK_RCVTSTAMPNS, /* %SO_TIMESTAMPNS setting */
902 	SOCK_LOCALROUTE, /* route locally only, %SO_DONTROUTE setting */
903 	SOCK_MEMALLOC, /* VM depends on this socket for swapping */
904 	SOCK_TIMESTAMPING_RX_SOFTWARE,  /* %SOF_TIMESTAMPING_RX_SOFTWARE */
905 	SOCK_FASYNC, /* fasync() active */
906 	SOCK_RXQ_OVFL,
907 	SOCK_ZEROCOPY, /* buffers from userspace */
908 	SOCK_WIFI_STATUS, /* push wifi status to userspace */
909 	SOCK_NOFCS, /* Tell NIC not to do the Ethernet FCS.
910 		     * Will use last 4 bytes of packet sent from
911 		     * user-space instead.
912 		     */
913 	SOCK_FILTER_LOCKED, /* Filter cannot be changed anymore */
914 	SOCK_SELECT_ERR_QUEUE, /* Wake select on error queue */
915 	SOCK_RCU_FREE, /* wait rcu grace period in sk_destruct() */
916 	SOCK_TXTIME,
917 	SOCK_XDP, /* XDP is attached */
918 	SOCK_TSTAMP_NEW, /* Indicates 64 bit timestamps always */
919 };
920 
921 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
922 
sock_copy_flags(struct sock * nsk,struct sock * osk)923 static inline void sock_copy_flags(struct sock *nsk, struct sock *osk)
924 {
925 	nsk->sk_flags = osk->sk_flags;
926 }
927 
sock_set_flag(struct sock * sk,enum sock_flags flag)928 static inline void sock_set_flag(struct sock *sk, enum sock_flags flag)
929 {
930 	__set_bit(flag, &sk->sk_flags);
931 }
932 
sock_reset_flag(struct sock * sk,enum sock_flags flag)933 static inline void sock_reset_flag(struct sock *sk, enum sock_flags flag)
934 {
935 	__clear_bit(flag, &sk->sk_flags);
936 }
937 
sock_valbool_flag(struct sock * sk,enum sock_flags bit,int valbool)938 static inline void sock_valbool_flag(struct sock *sk, enum sock_flags bit,
939 				     int valbool)
940 {
941 	if (valbool)
942 		sock_set_flag(sk, bit);
943 	else
944 		sock_reset_flag(sk, bit);
945 }
946 
sock_flag(const struct sock * sk,enum sock_flags flag)947 static inline bool sock_flag(const struct sock *sk, enum sock_flags flag)
948 {
949 	return test_bit(flag, &sk->sk_flags);
950 }
951 
952 #ifdef CONFIG_NET
953 DECLARE_STATIC_KEY_FALSE(memalloc_socks_key);
sk_memalloc_socks(void)954 static inline int sk_memalloc_socks(void)
955 {
956 	return static_branch_unlikely(&memalloc_socks_key);
957 }
958 
959 void __receive_sock(struct file *file);
960 #else
961 
sk_memalloc_socks(void)962 static inline int sk_memalloc_socks(void)
963 {
964 	return 0;
965 }
966 
__receive_sock(struct file * file)967 static inline void __receive_sock(struct file *file)
968 { }
969 #endif
970 
sk_gfp_mask(const struct sock * sk,gfp_t gfp_mask)971 static inline gfp_t sk_gfp_mask(const struct sock *sk, gfp_t gfp_mask)
972 {
973 	return gfp_mask | (sk->sk_allocation & __GFP_MEMALLOC);
974 }
975 
sk_acceptq_removed(struct sock * sk)976 static inline void sk_acceptq_removed(struct sock *sk)
977 {
978 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog - 1);
979 }
980 
sk_acceptq_added(struct sock * sk)981 static inline void sk_acceptq_added(struct sock *sk)
982 {
983 	WRITE_ONCE(sk->sk_ack_backlog, sk->sk_ack_backlog + 1);
984 }
985 
986 /* Note: If you think the test should be:
987  *	return READ_ONCE(sk->sk_ack_backlog) >= READ_ONCE(sk->sk_max_ack_backlog);
988  * Then please take a look at commit 64a146513f8f ("[NET]: Revert incorrect accept queue backlog changes.")
989  */
sk_acceptq_is_full(const struct sock * sk)990 static inline bool sk_acceptq_is_full(const struct sock *sk)
991 {
992 	return READ_ONCE(sk->sk_ack_backlog) > READ_ONCE(sk->sk_max_ack_backlog);
993 }
994 
995 /*
996  * Compute minimal free write space needed to queue new packets.
997  */
sk_stream_min_wspace(const struct sock * sk)998 static inline int sk_stream_min_wspace(const struct sock *sk)
999 {
1000 	return READ_ONCE(sk->sk_wmem_queued) >> 1;
1001 }
1002 
sk_stream_wspace(const struct sock * sk)1003 static inline int sk_stream_wspace(const struct sock *sk)
1004 {
1005 	return READ_ONCE(sk->sk_sndbuf) - READ_ONCE(sk->sk_wmem_queued);
1006 }
1007 
sk_wmem_queued_add(struct sock * sk,int val)1008 static inline void sk_wmem_queued_add(struct sock *sk, int val)
1009 {
1010 	WRITE_ONCE(sk->sk_wmem_queued, sk->sk_wmem_queued + val);
1011 }
1012 
1013 void sk_stream_write_space(struct sock *sk);
1014 
1015 /* OOB backlog add */
__sk_add_backlog(struct sock * sk,struct sk_buff * skb)1016 static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
1017 {
1018 	/* dont let skb dst not refcounted, we are going to leave rcu lock */
1019 	skb_dst_force(skb);
1020 
1021 	if (!sk->sk_backlog.tail)
1022 		WRITE_ONCE(sk->sk_backlog.head, skb);
1023 	else
1024 		sk->sk_backlog.tail->next = skb;
1025 
1026 	WRITE_ONCE(sk->sk_backlog.tail, skb);
1027 	skb->next = NULL;
1028 }
1029 
1030 /*
1031  * Take into account size of receive queue and backlog queue
1032  * Do not take into account this skb truesize,
1033  * to allow even a single big packet to come.
1034  */
sk_rcvqueues_full(const struct sock * sk,unsigned int limit)1035 static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
1036 {
1037 	unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
1038 
1039 	return qsize > limit;
1040 }
1041 
1042 /* The per-socket spinlock must be held here. */
sk_add_backlog(struct sock * sk,struct sk_buff * skb,unsigned int limit)1043 static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
1044 					      unsigned int limit)
1045 {
1046 	if (sk_rcvqueues_full(sk, limit))
1047 		return -ENOBUFS;
1048 
1049 	/*
1050 	 * If the skb was allocated from pfmemalloc reserves, only
1051 	 * allow SOCK_MEMALLOC sockets to use it as this socket is
1052 	 * helping free memory
1053 	 */
1054 	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
1055 		return -ENOMEM;
1056 
1057 	__sk_add_backlog(sk, skb);
1058 	sk->sk_backlog.len += skb->truesize;
1059 	return 0;
1060 }
1061 
1062 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
1063 
sk_backlog_rcv(struct sock * sk,struct sk_buff * skb)1064 static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
1065 {
1066 	if (sk_memalloc_socks() && skb_pfmemalloc(skb))
1067 		return __sk_backlog_rcv(sk, skb);
1068 
1069 	return sk->sk_backlog_rcv(sk, skb);
1070 }
1071 
sk_incoming_cpu_update(struct sock * sk)1072 static inline void sk_incoming_cpu_update(struct sock *sk)
1073 {
1074 	int cpu = raw_smp_processor_id();
1075 
1076 	if (unlikely(READ_ONCE(sk->sk_incoming_cpu) != cpu))
1077 		WRITE_ONCE(sk->sk_incoming_cpu, cpu);
1078 }
1079 
sock_rps_record_flow_hash(__u32 hash)1080 static inline void sock_rps_record_flow_hash(__u32 hash)
1081 {
1082 #ifdef CONFIG_RPS
1083 	struct rps_sock_flow_table *sock_flow_table;
1084 
1085 	rcu_read_lock();
1086 	sock_flow_table = rcu_dereference(rps_sock_flow_table);
1087 	rps_record_sock_flow(sock_flow_table, hash);
1088 	rcu_read_unlock();
1089 #endif
1090 }
1091 
sock_rps_record_flow(const struct sock * sk)1092 static inline void sock_rps_record_flow(const struct sock *sk)
1093 {
1094 #ifdef CONFIG_RPS
1095 	if (static_branch_unlikely(&rfs_needed)) {
1096 		/* Reading sk->sk_rxhash might incur an expensive cache line
1097 		 * miss.
1098 		 *
1099 		 * TCP_ESTABLISHED does cover almost all states where RFS
1100 		 * might be useful, and is cheaper [1] than testing :
1101 		 *	IPv4: inet_sk(sk)->inet_daddr
1102 		 * 	IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
1103 		 * OR	an additional socket flag
1104 		 * [1] : sk_state and sk_prot are in the same cache line.
1105 		 */
1106 		if (sk->sk_state == TCP_ESTABLISHED) {
1107 			/* This READ_ONCE() is paired with the WRITE_ONCE()
1108 			 * from sock_rps_save_rxhash() and sock_rps_reset_rxhash().
1109 			 */
1110 			sock_rps_record_flow_hash(READ_ONCE(sk->sk_rxhash));
1111 		}
1112 	}
1113 #endif
1114 }
1115 
sock_rps_save_rxhash(struct sock * sk,const struct sk_buff * skb)1116 static inline void sock_rps_save_rxhash(struct sock *sk,
1117 					const struct sk_buff *skb)
1118 {
1119 #ifdef CONFIG_RPS
1120 	/* The following WRITE_ONCE() is paired with the READ_ONCE()
1121 	 * here, and another one in sock_rps_record_flow().
1122 	 */
1123 	if (unlikely(READ_ONCE(sk->sk_rxhash) != skb->hash))
1124 		WRITE_ONCE(sk->sk_rxhash, skb->hash);
1125 #endif
1126 }
1127 
sock_rps_reset_rxhash(struct sock * sk)1128 static inline void sock_rps_reset_rxhash(struct sock *sk)
1129 {
1130 #ifdef CONFIG_RPS
1131 	/* Paired with READ_ONCE() in sock_rps_record_flow() */
1132 	WRITE_ONCE(sk->sk_rxhash, 0);
1133 #endif
1134 }
1135 
1136 #define sk_wait_event(__sk, __timeo, __condition, __wait)		\
1137 	({	int __rc;						\
1138 		release_sock(__sk);					\
1139 		__rc = __condition;					\
1140 		if (!__rc) {						\
1141 			*(__timeo) = wait_woken(__wait,			\
1142 						TASK_INTERRUPTIBLE,	\
1143 						*(__timeo));		\
1144 		}							\
1145 		sched_annotate_sleep();					\
1146 		lock_sock(__sk);					\
1147 		__rc = __condition;					\
1148 		__rc;							\
1149 	})
1150 
1151 int sk_stream_wait_connect(struct sock *sk, long *timeo_p);
1152 int sk_stream_wait_memory(struct sock *sk, long *timeo_p);
1153 void sk_stream_wait_close(struct sock *sk, long timeo_p);
1154 int sk_stream_error(struct sock *sk, int flags, int err);
1155 void sk_stream_kill_queues(struct sock *sk);
1156 void sk_set_memalloc(struct sock *sk);
1157 void sk_clear_memalloc(struct sock *sk);
1158 
1159 void __sk_flush_backlog(struct sock *sk);
1160 
sk_flush_backlog(struct sock * sk)1161 static inline bool sk_flush_backlog(struct sock *sk)
1162 {
1163 	if (unlikely(READ_ONCE(sk->sk_backlog.tail))) {
1164 		__sk_flush_backlog(sk);
1165 		return true;
1166 	}
1167 	return false;
1168 }
1169 
1170 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb);
1171 
1172 struct request_sock_ops;
1173 struct timewait_sock_ops;
1174 struct inet_hashinfo;
1175 struct raw_hashinfo;
1176 struct smc_hashinfo;
1177 struct module;
1178 struct sk_psock;
1179 
1180 /*
1181  * caches using SLAB_TYPESAFE_BY_RCU should let .next pointer from nulls nodes
1182  * un-modified. Special care is taken when initializing object to zero.
1183  */
sk_prot_clear_nulls(struct sock * sk,int size)1184 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1185 {
1186 	if (offsetof(struct sock, sk_node.next) != 0)
1187 		memset(sk, 0, offsetof(struct sock, sk_node.next));
1188 	memset(&sk->sk_node.pprev, 0,
1189 	       size - offsetof(struct sock, sk_node.pprev));
1190 }
1191 
1192 /* Networking protocol blocks we attach to sockets.
1193  * socket layer -> transport layer interface
1194  */
1195 struct proto {
1196 	void			(*close)(struct sock *sk,
1197 					long timeout);
1198 	int			(*pre_connect)(struct sock *sk,
1199 					struct sockaddr *uaddr,
1200 					int addr_len);
1201 	int			(*connect)(struct sock *sk,
1202 					struct sockaddr *uaddr,
1203 					int addr_len);
1204 	int			(*disconnect)(struct sock *sk, int flags);
1205 
1206 	struct sock *		(*accept)(struct sock *sk, int flags, int *err,
1207 					  bool kern);
1208 
1209 	int			(*ioctl)(struct sock *sk, int cmd,
1210 					 unsigned long arg);
1211 	int			(*init)(struct sock *sk);
1212 	void			(*destroy)(struct sock *sk);
1213 	void			(*shutdown)(struct sock *sk, int how);
1214 	int			(*setsockopt)(struct sock *sk, int level,
1215 					int optname, sockptr_t optval,
1216 					unsigned int optlen);
1217 	int			(*getsockopt)(struct sock *sk, int level,
1218 					int optname, char __user *optval,
1219 					int __user *option);
1220 	void			(*keepalive)(struct sock *sk, int valbool);
1221 #ifdef CONFIG_COMPAT
1222 	int			(*compat_ioctl)(struct sock *sk,
1223 					unsigned int cmd, unsigned long arg);
1224 #endif
1225 	int			(*sendmsg)(struct sock *sk, struct msghdr *msg,
1226 					   size_t len);
1227 	int			(*recvmsg)(struct sock *sk, struct msghdr *msg,
1228 					   size_t len, int noblock, int flags,
1229 					   int *addr_len);
1230 	int			(*sendpage)(struct sock *sk, struct page *page,
1231 					int offset, size_t size, int flags);
1232 	int			(*bind)(struct sock *sk,
1233 					struct sockaddr *addr, int addr_len);
1234 	int			(*bind_add)(struct sock *sk,
1235 					struct sockaddr *addr, int addr_len);
1236 
1237 	int			(*backlog_rcv) (struct sock *sk,
1238 						struct sk_buff *skb);
1239 	bool			(*bpf_bypass_getsockopt)(int level,
1240 							 int optname);
1241 
1242 	void		(*release_cb)(struct sock *sk);
1243 
1244 	/* Keeping track of sk's, looking them up, and port selection methods. */
1245 	int			(*hash)(struct sock *sk);
1246 	void			(*unhash)(struct sock *sk);
1247 	void			(*rehash)(struct sock *sk);
1248 	int			(*get_port)(struct sock *sk, unsigned short snum);
1249 #ifdef CONFIG_BPF_SYSCALL
1250 	int			(*psock_update_sk_prot)(struct sock *sk,
1251 							struct sk_psock *psock,
1252 							bool restore);
1253 #endif
1254 
1255 	/* Keeping track of sockets in use */
1256 #ifdef CONFIG_PROC_FS
1257 	unsigned int		inuse_idx;
1258 #endif
1259 
1260 	bool			(*stream_memory_free)(const struct sock *sk, int wake);
1261 	bool			(*sock_is_readable)(struct sock *sk);
1262 	/* Memory pressure */
1263 	void			(*enter_memory_pressure)(struct sock *sk);
1264 	void			(*leave_memory_pressure)(struct sock *sk);
1265 	atomic_long_t		*memory_allocated;	/* Current allocated memory. */
1266 	struct percpu_counter	*sockets_allocated;	/* Current number of sockets. */
1267 	/*
1268 	 * Pressure flag: try to collapse.
1269 	 * Technical note: it is used by multiple contexts non atomically.
1270 	 * Make sure to use READ_ONCE()/WRITE_ONCE() for all reads/writes.
1271 	 * All the __sk_mem_schedule() is of this nature: accounting
1272 	 * is strict, actions are advisory and have some latency.
1273 	 */
1274 	unsigned long		*memory_pressure;
1275 	long			*sysctl_mem;
1276 
1277 	int			*sysctl_wmem;
1278 	int			*sysctl_rmem;
1279 	u32			sysctl_wmem_offset;
1280 	u32			sysctl_rmem_offset;
1281 
1282 	int			max_header;
1283 	bool			no_autobind;
1284 
1285 	struct kmem_cache	*slab;
1286 	unsigned int		obj_size;
1287 	slab_flags_t		slab_flags;
1288 	unsigned int		useroffset;	/* Usercopy region offset */
1289 	unsigned int		usersize;	/* Usercopy region size */
1290 
1291 	unsigned int __percpu	*orphan_count;
1292 
1293 	struct request_sock_ops	*rsk_prot;
1294 	struct timewait_sock_ops *twsk_prot;
1295 
1296 	union {
1297 		struct inet_hashinfo	*hashinfo;
1298 		struct udp_table	*udp_table;
1299 		struct raw_hashinfo	*raw_hash;
1300 		struct smc_hashinfo	*smc_hash;
1301 	} h;
1302 
1303 	struct module		*owner;
1304 
1305 	char			name[32];
1306 
1307 	struct list_head	node;
1308 #ifdef SOCK_REFCNT_DEBUG
1309 	atomic_t		socks;
1310 #endif
1311 	int			(*diag_destroy)(struct sock *sk, int err);
1312 } __randomize_layout;
1313 
1314 int proto_register(struct proto *prot, int alloc_slab);
1315 void proto_unregister(struct proto *prot);
1316 int sock_load_diag_module(int family, int protocol);
1317 
1318 #ifdef SOCK_REFCNT_DEBUG
sk_refcnt_debug_inc(struct sock * sk)1319 static inline void sk_refcnt_debug_inc(struct sock *sk)
1320 {
1321 	atomic_inc(&sk->sk_prot->socks);
1322 }
1323 
sk_refcnt_debug_dec(struct sock * sk)1324 static inline void sk_refcnt_debug_dec(struct sock *sk)
1325 {
1326 	atomic_dec(&sk->sk_prot->socks);
1327 	printk(KERN_DEBUG "%s socket %p released, %d are still alive\n",
1328 	       sk->sk_prot->name, sk, atomic_read(&sk->sk_prot->socks));
1329 }
1330 
sk_refcnt_debug_release(const struct sock * sk)1331 static inline void sk_refcnt_debug_release(const struct sock *sk)
1332 {
1333 	if (refcount_read(&sk->sk_refcnt) != 1)
1334 		printk(KERN_DEBUG "Destruction of the %s socket %p delayed, refcnt=%d\n",
1335 		       sk->sk_prot->name, sk, refcount_read(&sk->sk_refcnt));
1336 }
1337 #else /* SOCK_REFCNT_DEBUG */
1338 #define sk_refcnt_debug_inc(sk) do { } while (0)
1339 #define sk_refcnt_debug_dec(sk) do { } while (0)
1340 #define sk_refcnt_debug_release(sk) do { } while (0)
1341 #endif /* SOCK_REFCNT_DEBUG */
1342 
1343 INDIRECT_CALLABLE_DECLARE(bool tcp_stream_memory_free(const struct sock *sk, int wake));
1344 
__sk_stream_memory_free(const struct sock * sk,int wake)1345 static inline bool __sk_stream_memory_free(const struct sock *sk, int wake)
1346 {
1347 	if (READ_ONCE(sk->sk_wmem_queued) >= READ_ONCE(sk->sk_sndbuf))
1348 		return false;
1349 
1350 #ifdef CONFIG_INET
1351 	return sk->sk_prot->stream_memory_free ?
1352 		INDIRECT_CALL_1(sk->sk_prot->stream_memory_free,
1353 			        tcp_stream_memory_free,
1354 				sk, wake) : true;
1355 #else
1356 	return sk->sk_prot->stream_memory_free ?
1357 		sk->sk_prot->stream_memory_free(sk, wake) : true;
1358 #endif
1359 }
1360 
sk_stream_memory_free(const struct sock * sk)1361 static inline bool sk_stream_memory_free(const struct sock *sk)
1362 {
1363 	return __sk_stream_memory_free(sk, 0);
1364 }
1365 
__sk_stream_is_writeable(const struct sock * sk,int wake)1366 static inline bool __sk_stream_is_writeable(const struct sock *sk, int wake)
1367 {
1368 	return sk_stream_wspace(sk) >= sk_stream_min_wspace(sk) &&
1369 	       __sk_stream_memory_free(sk, wake);
1370 }
1371 
sk_stream_is_writeable(const struct sock * sk)1372 static inline bool sk_stream_is_writeable(const struct sock *sk)
1373 {
1374 	return __sk_stream_is_writeable(sk, 0);
1375 }
1376 
sk_under_cgroup_hierarchy(struct sock * sk,struct cgroup * ancestor)1377 static inline int sk_under_cgroup_hierarchy(struct sock *sk,
1378 					    struct cgroup *ancestor)
1379 {
1380 #ifdef CONFIG_SOCK_CGROUP_DATA
1381 	return cgroup_is_descendant(sock_cgroup_ptr(&sk->sk_cgrp_data),
1382 				    ancestor);
1383 #else
1384 	return -ENOTSUPP;
1385 #endif
1386 }
1387 
sk_has_memory_pressure(const struct sock * sk)1388 static inline bool sk_has_memory_pressure(const struct sock *sk)
1389 {
1390 	return sk->sk_prot->memory_pressure != NULL;
1391 }
1392 
sk_under_global_memory_pressure(const struct sock * sk)1393 static inline bool sk_under_global_memory_pressure(const struct sock *sk)
1394 {
1395 	return sk->sk_prot->memory_pressure &&
1396 		!!READ_ONCE(*sk->sk_prot->memory_pressure);
1397 }
1398 
sk_under_memory_pressure(const struct sock * sk)1399 static inline bool sk_under_memory_pressure(const struct sock *sk)
1400 {
1401 	if (!sk->sk_prot->memory_pressure)
1402 		return false;
1403 
1404 	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
1405 	    mem_cgroup_under_socket_pressure(sk->sk_memcg))
1406 		return true;
1407 
1408 	return !!READ_ONCE(*sk->sk_prot->memory_pressure);
1409 }
1410 
1411 static inline long
sk_memory_allocated(const struct sock * sk)1412 sk_memory_allocated(const struct sock *sk)
1413 {
1414 	return atomic_long_read(sk->sk_prot->memory_allocated);
1415 }
1416 
1417 static inline long
sk_memory_allocated_add(struct sock * sk,int amt)1418 sk_memory_allocated_add(struct sock *sk, int amt)
1419 {
1420 	return atomic_long_add_return(amt, sk->sk_prot->memory_allocated);
1421 }
1422 
1423 static inline void
sk_memory_allocated_sub(struct sock * sk,int amt)1424 sk_memory_allocated_sub(struct sock *sk, int amt)
1425 {
1426 	atomic_long_sub(amt, sk->sk_prot->memory_allocated);
1427 }
1428 
1429 #define SK_ALLOC_PERCPU_COUNTER_BATCH 16
1430 
sk_sockets_allocated_dec(struct sock * sk)1431 static inline void sk_sockets_allocated_dec(struct sock *sk)
1432 {
1433 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, -1,
1434 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1435 }
1436 
sk_sockets_allocated_inc(struct sock * sk)1437 static inline void sk_sockets_allocated_inc(struct sock *sk)
1438 {
1439 	percpu_counter_add_batch(sk->sk_prot->sockets_allocated, 1,
1440 				 SK_ALLOC_PERCPU_COUNTER_BATCH);
1441 }
1442 
1443 static inline u64
sk_sockets_allocated_read_positive(struct sock * sk)1444 sk_sockets_allocated_read_positive(struct sock *sk)
1445 {
1446 	return percpu_counter_read_positive(sk->sk_prot->sockets_allocated);
1447 }
1448 
1449 static inline int
proto_sockets_allocated_sum_positive(struct proto * prot)1450 proto_sockets_allocated_sum_positive(struct proto *prot)
1451 {
1452 	return percpu_counter_sum_positive(prot->sockets_allocated);
1453 }
1454 
1455 static inline long
proto_memory_allocated(struct proto * prot)1456 proto_memory_allocated(struct proto *prot)
1457 {
1458 	return atomic_long_read(prot->memory_allocated);
1459 }
1460 
1461 static inline bool
proto_memory_pressure(struct proto * prot)1462 proto_memory_pressure(struct proto *prot)
1463 {
1464 	if (!prot->memory_pressure)
1465 		return false;
1466 	return !!READ_ONCE(*prot->memory_pressure);
1467 }
1468 
1469 
1470 #ifdef CONFIG_PROC_FS
1471 /* Called with local bh disabled */
1472 void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc);
1473 int sock_prot_inuse_get(struct net *net, struct proto *proto);
1474 int sock_inuse_get(struct net *net);
1475 #else
sock_prot_inuse_add(struct net * net,struct proto * prot,int inc)1476 static inline void sock_prot_inuse_add(struct net *net, struct proto *prot,
1477 		int inc)
1478 {
1479 }
1480 #endif
1481 
1482 
1483 /* With per-bucket locks this operation is not-atomic, so that
1484  * this version is not worse.
1485  */
__sk_prot_rehash(struct sock * sk)1486 static inline int __sk_prot_rehash(struct sock *sk)
1487 {
1488 	sk->sk_prot->unhash(sk);
1489 	return sk->sk_prot->hash(sk);
1490 }
1491 
1492 /* About 10 seconds */
1493 #define SOCK_DESTROY_TIME (10*HZ)
1494 
1495 /* Sockets 0-1023 can't be bound to unless you are superuser */
1496 #define PROT_SOCK	1024
1497 
1498 #define SHUTDOWN_MASK	3
1499 #define RCV_SHUTDOWN	1
1500 #define SEND_SHUTDOWN	2
1501 
1502 #define SOCK_BINDADDR_LOCK	4
1503 #define SOCK_BINDPORT_LOCK	8
1504 
1505 struct socket_alloc {
1506 	struct socket socket;
1507 	struct inode vfs_inode;
1508 };
1509 
SOCKET_I(struct inode * inode)1510 static inline struct socket *SOCKET_I(struct inode *inode)
1511 {
1512 	return &container_of(inode, struct socket_alloc, vfs_inode)->socket;
1513 }
1514 
SOCK_INODE(struct socket * socket)1515 static inline struct inode *SOCK_INODE(struct socket *socket)
1516 {
1517 	return &container_of(socket, struct socket_alloc, socket)->vfs_inode;
1518 }
1519 
1520 /*
1521  * Functions for memory accounting
1522  */
1523 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind);
1524 int __sk_mem_schedule(struct sock *sk, int size, int kind);
1525 void __sk_mem_reduce_allocated(struct sock *sk, int amount);
1526 void __sk_mem_reclaim(struct sock *sk, int amount);
1527 
1528 /* We used to have PAGE_SIZE here, but systems with 64KB pages
1529  * do not necessarily have 16x time more memory than 4KB ones.
1530  */
1531 #define SK_MEM_QUANTUM 4096
1532 #define SK_MEM_QUANTUM_SHIFT ilog2(SK_MEM_QUANTUM)
1533 #define SK_MEM_SEND	0
1534 #define SK_MEM_RECV	1
1535 
1536 /* sysctl_mem values are in pages, we convert them in SK_MEM_QUANTUM units */
sk_prot_mem_limits(const struct sock * sk,int index)1537 static inline long sk_prot_mem_limits(const struct sock *sk, int index)
1538 {
1539 	long val = READ_ONCE(sk->sk_prot->sysctl_mem[index]);
1540 
1541 #if PAGE_SIZE > SK_MEM_QUANTUM
1542 	val <<= PAGE_SHIFT - SK_MEM_QUANTUM_SHIFT;
1543 #elif PAGE_SIZE < SK_MEM_QUANTUM
1544 	val >>= SK_MEM_QUANTUM_SHIFT - PAGE_SHIFT;
1545 #endif
1546 	return val;
1547 }
1548 
sk_mem_pages(int amt)1549 static inline int sk_mem_pages(int amt)
1550 {
1551 	return (amt + SK_MEM_QUANTUM - 1) >> SK_MEM_QUANTUM_SHIFT;
1552 }
1553 
sk_has_account(struct sock * sk)1554 static inline bool sk_has_account(struct sock *sk)
1555 {
1556 	/* return true if protocol supports memory accounting */
1557 	return !!sk->sk_prot->memory_allocated;
1558 }
1559 
sk_wmem_schedule(struct sock * sk,int size)1560 static inline bool sk_wmem_schedule(struct sock *sk, int size)
1561 {
1562 	int delta;
1563 
1564 	if (!sk_has_account(sk))
1565 		return true;
1566 	delta = size - sk->sk_forward_alloc;
1567 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_SEND);
1568 }
1569 
1570 static inline bool
sk_rmem_schedule(struct sock * sk,struct sk_buff * skb,int size)1571 sk_rmem_schedule(struct sock *sk, struct sk_buff *skb, int size)
1572 {
1573 	int delta;
1574 
1575 	if (!sk_has_account(sk))
1576 		return true;
1577 	delta = size - sk->sk_forward_alloc;
1578 	return delta <= 0 || __sk_mem_schedule(sk, delta, SK_MEM_RECV) ||
1579 		skb_pfmemalloc(skb);
1580 }
1581 
sk_mem_reclaim(struct sock * sk)1582 static inline void sk_mem_reclaim(struct sock *sk)
1583 {
1584 	if (!sk_has_account(sk))
1585 		return;
1586 	if (sk->sk_forward_alloc >= SK_MEM_QUANTUM)
1587 		__sk_mem_reclaim(sk, sk->sk_forward_alloc);
1588 }
1589 
sk_mem_reclaim_partial(struct sock * sk)1590 static inline void sk_mem_reclaim_partial(struct sock *sk)
1591 {
1592 	if (!sk_has_account(sk))
1593 		return;
1594 	if (sk->sk_forward_alloc > SK_MEM_QUANTUM)
1595 		__sk_mem_reclaim(sk, sk->sk_forward_alloc - 1);
1596 }
1597 
sk_mem_charge(struct sock * sk,int size)1598 static inline void sk_mem_charge(struct sock *sk, int size)
1599 {
1600 	if (!sk_has_account(sk))
1601 		return;
1602 	sk->sk_forward_alloc -= size;
1603 }
1604 
sk_mem_uncharge(struct sock * sk,int size)1605 static inline void sk_mem_uncharge(struct sock *sk, int size)
1606 {
1607 	if (!sk_has_account(sk))
1608 		return;
1609 	sk->sk_forward_alloc += size;
1610 
1611 	/* Avoid a possible overflow.
1612 	 * TCP send queues can make this happen, if sk_mem_reclaim()
1613 	 * is not called and more than 2 GBytes are released at once.
1614 	 *
1615 	 * If we reach 2 MBytes, reclaim 1 MBytes right now, there is
1616 	 * no need to hold that much forward allocation anyway.
1617 	 */
1618 	if (unlikely(sk->sk_forward_alloc >= 1 << 21))
1619 		__sk_mem_reclaim(sk, 1 << 20);
1620 }
1621 
1622 DECLARE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key);
sk_wmem_free_skb(struct sock * sk,struct sk_buff * skb)1623 static inline void sk_wmem_free_skb(struct sock *sk, struct sk_buff *skb)
1624 {
1625 	sk_wmem_queued_add(sk, -skb->truesize);
1626 	sk_mem_uncharge(sk, skb->truesize);
1627 	if (static_branch_unlikely(&tcp_tx_skb_cache_key) &&
1628 	    !sk->sk_tx_skb_cache && !skb_cloned(skb)) {
1629 		skb_ext_reset(skb);
1630 		skb_zcopy_clear(skb, true);
1631 		sk->sk_tx_skb_cache = skb;
1632 		return;
1633 	}
1634 	__kfree_skb(skb);
1635 }
1636 
sock_release_ownership(struct sock * sk)1637 static inline void sock_release_ownership(struct sock *sk)
1638 {
1639 	if (sk->sk_lock.owned) {
1640 		sk->sk_lock.owned = 0;
1641 
1642 		/* The sk_lock has mutex_unlock() semantics: */
1643 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1644 	}
1645 }
1646 
1647 /*
1648  * Macro so as to not evaluate some arguments when
1649  * lockdep is not enabled.
1650  *
1651  * Mark both the sk_lock and the sk_lock.slock as a
1652  * per-address-family lock class.
1653  */
1654 #define sock_lock_init_class_and_name(sk, sname, skey, name, key)	\
1655 do {									\
1656 	sk->sk_lock.owned = 0;						\
1657 	init_waitqueue_head(&sk->sk_lock.wq);				\
1658 	spin_lock_init(&(sk)->sk_lock.slock);				\
1659 	debug_check_no_locks_freed((void *)&(sk)->sk_lock,		\
1660 			sizeof((sk)->sk_lock));				\
1661 	lockdep_set_class_and_name(&(sk)->sk_lock.slock,		\
1662 				(skey), (sname));				\
1663 	lockdep_init_map(&(sk)->sk_lock.dep_map, (name), (key), 0);	\
1664 } while (0)
1665 
lockdep_sock_is_held(const struct sock * sk)1666 static inline bool lockdep_sock_is_held(const struct sock *sk)
1667 {
1668 	return lockdep_is_held(&sk->sk_lock) ||
1669 	       lockdep_is_held(&sk->sk_lock.slock);
1670 }
1671 
1672 void lock_sock_nested(struct sock *sk, int subclass);
1673 
lock_sock(struct sock * sk)1674 static inline void lock_sock(struct sock *sk)
1675 {
1676 	lock_sock_nested(sk, 0);
1677 }
1678 
1679 void __lock_sock(struct sock *sk);
1680 void __release_sock(struct sock *sk);
1681 void release_sock(struct sock *sk);
1682 
1683 /* BH context may only use the following locking interface. */
1684 #define bh_lock_sock(__sk)	spin_lock(&((__sk)->sk_lock.slock))
1685 #define bh_lock_sock_nested(__sk) \
1686 				spin_lock_nested(&((__sk)->sk_lock.slock), \
1687 				SINGLE_DEPTH_NESTING)
1688 #define bh_unlock_sock(__sk)	spin_unlock(&((__sk)->sk_lock.slock))
1689 
1690 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock);
1691 
1692 /**
1693  * lock_sock_fast - fast version of lock_sock
1694  * @sk: socket
1695  *
1696  * This version should be used for very small section, where process wont block
1697  * return false if fast path is taken:
1698  *
1699  *   sk_lock.slock locked, owned = 0, BH disabled
1700  *
1701  * return true if slow path is taken:
1702  *
1703  *   sk_lock.slock unlocked, owned = 1, BH enabled
1704  */
lock_sock_fast(struct sock * sk)1705 static inline bool lock_sock_fast(struct sock *sk)
1706 {
1707 	/* The sk_lock has mutex_lock() semantics here. */
1708 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
1709 
1710 	return __lock_sock_fast(sk);
1711 }
1712 
1713 /* fast socket lock variant for caller already holding a [different] socket lock */
lock_sock_fast_nested(struct sock * sk)1714 static inline bool lock_sock_fast_nested(struct sock *sk)
1715 {
1716 	mutex_acquire(&sk->sk_lock.dep_map, SINGLE_DEPTH_NESTING, 0, _RET_IP_);
1717 
1718 	return __lock_sock_fast(sk);
1719 }
1720 
1721 /**
1722  * unlock_sock_fast - complement of lock_sock_fast
1723  * @sk: socket
1724  * @slow: slow mode
1725  *
1726  * fast unlock socket for user context.
1727  * If slow mode is on, we call regular release_sock()
1728  */
unlock_sock_fast(struct sock * sk,bool slow)1729 static inline void unlock_sock_fast(struct sock *sk, bool slow)
1730 	__releases(&sk->sk_lock.slock)
1731 {
1732 	if (slow) {
1733 		release_sock(sk);
1734 		__release(&sk->sk_lock.slock);
1735 	} else {
1736 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
1737 		spin_unlock_bh(&sk->sk_lock.slock);
1738 	}
1739 }
1740 
1741 /* Used by processes to "lock" a socket state, so that
1742  * interrupts and bottom half handlers won't change it
1743  * from under us. It essentially blocks any incoming
1744  * packets, so that we won't get any new data or any
1745  * packets that change the state of the socket.
1746  *
1747  * While locked, BH processing will add new packets to
1748  * the backlog queue.  This queue is processed by the
1749  * owner of the socket lock right before it is released.
1750  *
1751  * Since ~2.3.5 it is also exclusive sleep lock serializing
1752  * accesses from user process context.
1753  */
1754 
sock_owned_by_me(const struct sock * sk)1755 static inline void sock_owned_by_me(const struct sock *sk)
1756 {
1757 #ifdef CONFIG_LOCKDEP
1758 	WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
1759 #endif
1760 }
1761 
sock_owned_by_user(const struct sock * sk)1762 static inline bool sock_owned_by_user(const struct sock *sk)
1763 {
1764 	sock_owned_by_me(sk);
1765 	return sk->sk_lock.owned;
1766 }
1767 
sock_owned_by_user_nocheck(const struct sock * sk)1768 static inline bool sock_owned_by_user_nocheck(const struct sock *sk)
1769 {
1770 	return sk->sk_lock.owned;
1771 }
1772 
1773 /* no reclassification while locks are held */
sock_allow_reclassification(const struct sock * csk)1774 static inline bool sock_allow_reclassification(const struct sock *csk)
1775 {
1776 	struct sock *sk = (struct sock *)csk;
1777 
1778 	return !sk->sk_lock.owned && !spin_is_locked(&sk->sk_lock.slock);
1779 }
1780 
1781 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1782 		      struct proto *prot, int kern);
1783 void sk_free(struct sock *sk);
1784 void sk_destruct(struct sock *sk);
1785 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority);
1786 void sk_free_unlock_clone(struct sock *sk);
1787 
1788 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1789 			     gfp_t priority);
1790 void __sock_wfree(struct sk_buff *skb);
1791 void sock_wfree(struct sk_buff *skb);
1792 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
1793 			     gfp_t priority);
1794 void skb_orphan_partial(struct sk_buff *skb);
1795 void sock_rfree(struct sk_buff *skb);
1796 void sock_efree(struct sk_buff *skb);
1797 #ifdef CONFIG_INET
1798 void sock_edemux(struct sk_buff *skb);
1799 void sock_pfree(struct sk_buff *skb);
1800 #else
1801 #define sock_edemux sock_efree
1802 #endif
1803 
1804 int sock_setsockopt(struct socket *sock, int level, int op,
1805 		    sockptr_t optval, unsigned int optlen);
1806 
1807 int sock_getsockopt(struct socket *sock, int level, int op,
1808 		    char __user *optval, int __user *optlen);
1809 int sock_gettstamp(struct socket *sock, void __user *userstamp,
1810 		   bool timeval, bool time32);
1811 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1812 				    int noblock, int *errcode);
1813 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1814 				     unsigned long data_len, int noblock,
1815 				     int *errcode, int max_page_order);
1816 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
1817 void sock_kfree_s(struct sock *sk, void *mem, int size);
1818 void sock_kzfree_s(struct sock *sk, void *mem, int size);
1819 void sk_send_sigurg(struct sock *sk);
1820 
1821 struct sockcm_cookie {
1822 	u64 transmit_time;
1823 	u32 mark;
1824 	u16 tsflags;
1825 };
1826 
sockcm_init(struct sockcm_cookie * sockc,const struct sock * sk)1827 static inline void sockcm_init(struct sockcm_cookie *sockc,
1828 			       const struct sock *sk)
1829 {
1830 	*sockc = (struct sockcm_cookie) { .tsflags = sk->sk_tsflags };
1831 }
1832 
1833 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1834 		     struct sockcm_cookie *sockc);
1835 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1836 		   struct sockcm_cookie *sockc);
1837 
1838 /*
1839  * Functions to fill in entries in struct proto_ops when a protocol
1840  * does not implement a particular function.
1841  */
1842 int sock_no_bind(struct socket *, struct sockaddr *, int);
1843 int sock_no_connect(struct socket *, struct sockaddr *, int, int);
1844 int sock_no_socketpair(struct socket *, struct socket *);
1845 int sock_no_accept(struct socket *, struct socket *, int, bool);
1846 int sock_no_getname(struct socket *, struct sockaddr *, int);
1847 int sock_no_ioctl(struct socket *, unsigned int, unsigned long);
1848 int sock_no_listen(struct socket *, int);
1849 int sock_no_shutdown(struct socket *, int);
1850 int sock_no_sendmsg(struct socket *, struct msghdr *, size_t);
1851 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t len);
1852 int sock_no_recvmsg(struct socket *, struct msghdr *, size_t, int);
1853 int sock_no_mmap(struct file *file, struct socket *sock,
1854 		 struct vm_area_struct *vma);
1855 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset,
1856 			 size_t size, int flags);
1857 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
1858 				int offset, size_t size, int flags);
1859 
1860 /*
1861  * Functions to fill in entries in struct proto_ops when a protocol
1862  * uses the inet style.
1863  */
1864 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1865 				  char __user *optval, int __user *optlen);
1866 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
1867 			int flags);
1868 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1869 			   sockptr_t optval, unsigned int optlen);
1870 
1871 void sk_common_release(struct sock *sk);
1872 
1873 /*
1874  *	Default socket callbacks and setup code
1875  */
1876 
1877 /* Initialise core socket variables using an explicit uid. */
1878 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid);
1879 
1880 /* Initialise core socket variables.
1881  * Assumes struct socket *sock is embedded in a struct socket_alloc.
1882  */
1883 void sock_init_data(struct socket *sock, struct sock *sk);
1884 
1885 /*
1886  * Socket reference counting postulates.
1887  *
1888  * * Each user of socket SHOULD hold a reference count.
1889  * * Each access point to socket (an hash table bucket, reference from a list,
1890  *   running timer, skb in flight MUST hold a reference count.
1891  * * When reference count hits 0, it means it will never increase back.
1892  * * When reference count hits 0, it means that no references from
1893  *   outside exist to this socket and current process on current CPU
1894  *   is last user and may/should destroy this socket.
1895  * * sk_free is called from any context: process, BH, IRQ. When
1896  *   it is called, socket has no references from outside -> sk_free
1897  *   may release descendant resources allocated by the socket, but
1898  *   to the time when it is called, socket is NOT referenced by any
1899  *   hash tables, lists etc.
1900  * * Packets, delivered from outside (from network or from another process)
1901  *   and enqueued on receive/error queues SHOULD NOT grab reference count,
1902  *   when they sit in queue. Otherwise, packets will leak to hole, when
1903  *   socket is looked up by one cpu and unhasing is made by another CPU.
1904  *   It is true for udp/raw, netlink (leak to receive and error queues), tcp
1905  *   (leak to backlog). Packet socket does all the processing inside
1906  *   BR_NETPROTO_LOCK, so that it has not this race condition. UNIX sockets
1907  *   use separate SMP lock, so that they are prone too.
1908  */
1909 
1910 /* Ungrab socket and destroy it, if it was the last reference. */
sock_put(struct sock * sk)1911 static inline void sock_put(struct sock *sk)
1912 {
1913 	if (refcount_dec_and_test(&sk->sk_refcnt))
1914 		sk_free(sk);
1915 }
1916 /* Generic version of sock_put(), dealing with all sockets
1917  * (TCP_TIMEWAIT, TCP_NEW_SYN_RECV, ESTABLISHED...)
1918  */
1919 void sock_gen_put(struct sock *sk);
1920 
1921 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested,
1922 		     unsigned int trim_cap, bool refcounted);
sk_receive_skb(struct sock * sk,struct sk_buff * skb,const int nested)1923 static inline int sk_receive_skb(struct sock *sk, struct sk_buff *skb,
1924 				 const int nested)
1925 {
1926 	return __sk_receive_skb(sk, skb, nested, 1, true);
1927 }
1928 
sk_tx_queue_set(struct sock * sk,int tx_queue)1929 static inline void sk_tx_queue_set(struct sock *sk, int tx_queue)
1930 {
1931 	/* sk_tx_queue_mapping accept only upto a 16-bit value */
1932 	if (WARN_ON_ONCE((unsigned short)tx_queue >= USHRT_MAX))
1933 		return;
1934 	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1935 	 * other WRITE_ONCE() because socket lock might be not held.
1936 	 */
1937 	WRITE_ONCE(sk->sk_tx_queue_mapping, tx_queue);
1938 }
1939 
1940 #define NO_QUEUE_MAPPING	USHRT_MAX
1941 
sk_tx_queue_clear(struct sock * sk)1942 static inline void sk_tx_queue_clear(struct sock *sk)
1943 {
1944 	/* Paired with READ_ONCE() in sk_tx_queue_get() and
1945 	 * other WRITE_ONCE() because socket lock might be not held.
1946 	 */
1947 	WRITE_ONCE(sk->sk_tx_queue_mapping, NO_QUEUE_MAPPING);
1948 }
1949 
sk_tx_queue_get(const struct sock * sk)1950 static inline int sk_tx_queue_get(const struct sock *sk)
1951 {
1952 	if (sk) {
1953 		/* Paired with WRITE_ONCE() in sk_tx_queue_clear()
1954 		 * and sk_tx_queue_set().
1955 		 */
1956 		int val = READ_ONCE(sk->sk_tx_queue_mapping);
1957 
1958 		if (val != NO_QUEUE_MAPPING)
1959 			return val;
1960 	}
1961 	return -1;
1962 }
1963 
sk_rx_queue_set(struct sock * sk,const struct sk_buff * skb)1964 static inline void sk_rx_queue_set(struct sock *sk, const struct sk_buff *skb)
1965 {
1966 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1967 	if (skb_rx_queue_recorded(skb)) {
1968 		u16 rx_queue = skb_get_rx_queue(skb);
1969 
1970 		if (WARN_ON_ONCE(rx_queue == NO_QUEUE_MAPPING))
1971 			return;
1972 
1973 		sk->sk_rx_queue_mapping = rx_queue;
1974 	}
1975 #endif
1976 }
1977 
sk_rx_queue_clear(struct sock * sk)1978 static inline void sk_rx_queue_clear(struct sock *sk)
1979 {
1980 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1981 	sk->sk_rx_queue_mapping = NO_QUEUE_MAPPING;
1982 #endif
1983 }
1984 
sk_rx_queue_get(const struct sock * sk)1985 static inline int sk_rx_queue_get(const struct sock *sk)
1986 {
1987 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
1988 	if (sk && sk->sk_rx_queue_mapping != NO_QUEUE_MAPPING)
1989 		return sk->sk_rx_queue_mapping;
1990 #endif
1991 
1992 	return -1;
1993 }
1994 
sk_set_socket(struct sock * sk,struct socket * sock)1995 static inline void sk_set_socket(struct sock *sk, struct socket *sock)
1996 {
1997 	sk->sk_socket = sock;
1998 }
1999 
sk_sleep(struct sock * sk)2000 static inline wait_queue_head_t *sk_sleep(struct sock *sk)
2001 {
2002 	BUILD_BUG_ON(offsetof(struct socket_wq, wait) != 0);
2003 	return &rcu_dereference_raw(sk->sk_wq)->wait;
2004 }
2005 /* Detach socket from process context.
2006  * Announce socket dead, detach it from wait queue and inode.
2007  * Note that parent inode held reference count on this struct sock,
2008  * we do not release it in this function, because protocol
2009  * probably wants some additional cleanups or even continuing
2010  * to work with this socket (TCP).
2011  */
sock_orphan(struct sock * sk)2012 static inline void sock_orphan(struct sock *sk)
2013 {
2014 	write_lock_bh(&sk->sk_callback_lock);
2015 	sock_set_flag(sk, SOCK_DEAD);
2016 	sk_set_socket(sk, NULL);
2017 	sk->sk_wq  = NULL;
2018 	write_unlock_bh(&sk->sk_callback_lock);
2019 }
2020 
sock_graft(struct sock * sk,struct socket * parent)2021 static inline void sock_graft(struct sock *sk, struct socket *parent)
2022 {
2023 	WARN_ON(parent->sk);
2024 	write_lock_bh(&sk->sk_callback_lock);
2025 	rcu_assign_pointer(sk->sk_wq, &parent->wq);
2026 	parent->sk = sk;
2027 	sk_set_socket(sk, parent);
2028 	sk->sk_uid = SOCK_INODE(parent)->i_uid;
2029 	security_sock_graft(sk, parent);
2030 	write_unlock_bh(&sk->sk_callback_lock);
2031 }
2032 
2033 kuid_t sock_i_uid(struct sock *sk);
2034 unsigned long __sock_i_ino(struct sock *sk);
2035 unsigned long sock_i_ino(struct sock *sk);
2036 
sock_net_uid(const struct net * net,const struct sock * sk)2037 static inline kuid_t sock_net_uid(const struct net *net, const struct sock *sk)
2038 {
2039 	return sk ? sk->sk_uid : make_kuid(net->user_ns, 0);
2040 }
2041 
net_tx_rndhash(void)2042 static inline u32 net_tx_rndhash(void)
2043 {
2044 	u32 v = prandom_u32();
2045 
2046 	return v ?: 1;
2047 }
2048 
sk_set_txhash(struct sock * sk)2049 static inline void sk_set_txhash(struct sock *sk)
2050 {
2051 	/* This pairs with READ_ONCE() in skb_set_hash_from_sk() */
2052 	WRITE_ONCE(sk->sk_txhash, net_tx_rndhash());
2053 }
2054 
sk_rethink_txhash(struct sock * sk)2055 static inline bool sk_rethink_txhash(struct sock *sk)
2056 {
2057 	if (sk->sk_txhash) {
2058 		sk_set_txhash(sk);
2059 		return true;
2060 	}
2061 	return false;
2062 }
2063 
2064 static inline struct dst_entry *
__sk_dst_get(struct sock * sk)2065 __sk_dst_get(struct sock *sk)
2066 {
2067 	return rcu_dereference_check(sk->sk_dst_cache,
2068 				     lockdep_sock_is_held(sk));
2069 }
2070 
2071 static inline struct dst_entry *
sk_dst_get(struct sock * sk)2072 sk_dst_get(struct sock *sk)
2073 {
2074 	struct dst_entry *dst;
2075 
2076 	rcu_read_lock();
2077 	dst = rcu_dereference(sk->sk_dst_cache);
2078 	if (dst && !atomic_inc_not_zero(&dst->__refcnt))
2079 		dst = NULL;
2080 	rcu_read_unlock();
2081 	return dst;
2082 }
2083 
__dst_negative_advice(struct sock * sk)2084 static inline void __dst_negative_advice(struct sock *sk)
2085 {
2086 	struct dst_entry *ndst, *dst = __sk_dst_get(sk);
2087 
2088 	if (dst && dst->ops->negative_advice) {
2089 		ndst = dst->ops->negative_advice(dst);
2090 
2091 		if (ndst != dst) {
2092 			rcu_assign_pointer(sk->sk_dst_cache, ndst);
2093 			sk_tx_queue_clear(sk);
2094 			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2095 		}
2096 	}
2097 }
2098 
dst_negative_advice(struct sock * sk)2099 static inline void dst_negative_advice(struct sock *sk)
2100 {
2101 	sk_rethink_txhash(sk);
2102 	__dst_negative_advice(sk);
2103 }
2104 
2105 static inline void
__sk_dst_set(struct sock * sk,struct dst_entry * dst)2106 __sk_dst_set(struct sock *sk, struct dst_entry *dst)
2107 {
2108 	struct dst_entry *old_dst;
2109 
2110 	sk_tx_queue_clear(sk);
2111 	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2112 	old_dst = rcu_dereference_protected(sk->sk_dst_cache,
2113 					    lockdep_sock_is_held(sk));
2114 	rcu_assign_pointer(sk->sk_dst_cache, dst);
2115 	dst_release(old_dst);
2116 }
2117 
2118 static inline void
sk_dst_set(struct sock * sk,struct dst_entry * dst)2119 sk_dst_set(struct sock *sk, struct dst_entry *dst)
2120 {
2121 	struct dst_entry *old_dst;
2122 
2123 	sk_tx_queue_clear(sk);
2124 	WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2125 	old_dst = xchg((__force struct dst_entry **)&sk->sk_dst_cache, dst);
2126 	dst_release(old_dst);
2127 }
2128 
2129 static inline void
__sk_dst_reset(struct sock * sk)2130 __sk_dst_reset(struct sock *sk)
2131 {
2132 	__sk_dst_set(sk, NULL);
2133 }
2134 
2135 static inline void
sk_dst_reset(struct sock * sk)2136 sk_dst_reset(struct sock *sk)
2137 {
2138 	sk_dst_set(sk, NULL);
2139 }
2140 
2141 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie);
2142 
2143 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie);
2144 
sk_dst_confirm(struct sock * sk)2145 static inline void sk_dst_confirm(struct sock *sk)
2146 {
2147 	if (!READ_ONCE(sk->sk_dst_pending_confirm))
2148 		WRITE_ONCE(sk->sk_dst_pending_confirm, 1);
2149 }
2150 
sock_confirm_neigh(struct sk_buff * skb,struct neighbour * n)2151 static inline void sock_confirm_neigh(struct sk_buff *skb, struct neighbour *n)
2152 {
2153 	if (skb_get_dst_pending_confirm(skb)) {
2154 		struct sock *sk = skb->sk;
2155 		unsigned long now = jiffies;
2156 
2157 		/* avoid dirtying neighbour */
2158 		if (READ_ONCE(n->confirmed) != now)
2159 			WRITE_ONCE(n->confirmed, now);
2160 		if (sk && READ_ONCE(sk->sk_dst_pending_confirm))
2161 			WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
2162 	}
2163 }
2164 
2165 bool sk_mc_loop(struct sock *sk);
2166 
sk_can_gso(const struct sock * sk)2167 static inline bool sk_can_gso(const struct sock *sk)
2168 {
2169 	return net_gso_ok(sk->sk_route_caps, sk->sk_gso_type);
2170 }
2171 
2172 void sk_setup_caps(struct sock *sk, struct dst_entry *dst);
2173 
sk_nocaps_add(struct sock * sk,netdev_features_t flags)2174 static inline void sk_nocaps_add(struct sock *sk, netdev_features_t flags)
2175 {
2176 	sk->sk_route_nocaps |= flags;
2177 	sk->sk_route_caps &= ~flags;
2178 }
2179 
skb_do_copy_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,char * to,int copy,int offset)2180 static inline int skb_do_copy_data_nocache(struct sock *sk, struct sk_buff *skb,
2181 					   struct iov_iter *from, char *to,
2182 					   int copy, int offset)
2183 {
2184 	if (skb->ip_summed == CHECKSUM_NONE) {
2185 		__wsum csum = 0;
2186 		if (!csum_and_copy_from_iter_full(to, copy, &csum, from))
2187 			return -EFAULT;
2188 		skb->csum = csum_block_add(skb->csum, csum, offset);
2189 	} else if (sk->sk_route_caps & NETIF_F_NOCACHE_COPY) {
2190 		if (!copy_from_iter_full_nocache(to, copy, from))
2191 			return -EFAULT;
2192 	} else if (!copy_from_iter_full(to, copy, from))
2193 		return -EFAULT;
2194 
2195 	return 0;
2196 }
2197 
skb_add_data_nocache(struct sock * sk,struct sk_buff * skb,struct iov_iter * from,int copy)2198 static inline int skb_add_data_nocache(struct sock *sk, struct sk_buff *skb,
2199 				       struct iov_iter *from, int copy)
2200 {
2201 	int err, offset = skb->len;
2202 
2203 	err = skb_do_copy_data_nocache(sk, skb, from, skb_put(skb, copy),
2204 				       copy, offset);
2205 	if (err)
2206 		__skb_trim(skb, offset);
2207 
2208 	return err;
2209 }
2210 
skb_copy_to_page_nocache(struct sock * sk,struct iov_iter * from,struct sk_buff * skb,struct page * page,int off,int copy)2211 static inline int skb_copy_to_page_nocache(struct sock *sk, struct iov_iter *from,
2212 					   struct sk_buff *skb,
2213 					   struct page *page,
2214 					   int off, int copy)
2215 {
2216 	int err;
2217 
2218 	err = skb_do_copy_data_nocache(sk, skb, from, page_address(page) + off,
2219 				       copy, skb->len);
2220 	if (err)
2221 		return err;
2222 
2223 	skb->len	     += copy;
2224 	skb->data_len	     += copy;
2225 	skb->truesize	     += copy;
2226 	sk_wmem_queued_add(sk, copy);
2227 	sk_mem_charge(sk, copy);
2228 	return 0;
2229 }
2230 
2231 /**
2232  * sk_wmem_alloc_get - returns write allocations
2233  * @sk: socket
2234  *
2235  * Return: sk_wmem_alloc minus initial offset of one
2236  */
sk_wmem_alloc_get(const struct sock * sk)2237 static inline int sk_wmem_alloc_get(const struct sock *sk)
2238 {
2239 	return refcount_read(&sk->sk_wmem_alloc) - 1;
2240 }
2241 
2242 /**
2243  * sk_rmem_alloc_get - returns read allocations
2244  * @sk: socket
2245  *
2246  * Return: sk_rmem_alloc
2247  */
sk_rmem_alloc_get(const struct sock * sk)2248 static inline int sk_rmem_alloc_get(const struct sock *sk)
2249 {
2250 	return atomic_read(&sk->sk_rmem_alloc);
2251 }
2252 
2253 /**
2254  * sk_has_allocations - check if allocations are outstanding
2255  * @sk: socket
2256  *
2257  * Return: true if socket has write or read allocations
2258  */
sk_has_allocations(const struct sock * sk)2259 static inline bool sk_has_allocations(const struct sock *sk)
2260 {
2261 	return sk_wmem_alloc_get(sk) || sk_rmem_alloc_get(sk);
2262 }
2263 
2264 /**
2265  * skwq_has_sleeper - check if there are any waiting processes
2266  * @wq: struct socket_wq
2267  *
2268  * Return: true if socket_wq has waiting processes
2269  *
2270  * The purpose of the skwq_has_sleeper and sock_poll_wait is to wrap the memory
2271  * barrier call. They were added due to the race found within the tcp code.
2272  *
2273  * Consider following tcp code paths::
2274  *
2275  *   CPU1                CPU2
2276  *   sys_select          receive packet
2277  *   ...                 ...
2278  *   __add_wait_queue    update tp->rcv_nxt
2279  *   ...                 ...
2280  *   tp->rcv_nxt check   sock_def_readable
2281  *   ...                 {
2282  *   schedule               rcu_read_lock();
2283  *                          wq = rcu_dereference(sk->sk_wq);
2284  *                          if (wq && waitqueue_active(&wq->wait))
2285  *                              wake_up_interruptible(&wq->wait)
2286  *                          ...
2287  *                       }
2288  *
2289  * The race for tcp fires when the __add_wait_queue changes done by CPU1 stay
2290  * in its cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1
2291  * could then endup calling schedule and sleep forever if there are no more
2292  * data on the socket.
2293  *
2294  */
skwq_has_sleeper(struct socket_wq * wq)2295 static inline bool skwq_has_sleeper(struct socket_wq *wq)
2296 {
2297 	return wq && wq_has_sleeper(&wq->wait);
2298 }
2299 
2300 /**
2301  * sock_poll_wait - place memory barrier behind the poll_wait call.
2302  * @filp:           file
2303  * @sock:           socket to wait on
2304  * @p:              poll_table
2305  *
2306  * See the comments in the wq_has_sleeper function.
2307  */
sock_poll_wait(struct file * filp,struct socket * sock,poll_table * p)2308 static inline void sock_poll_wait(struct file *filp, struct socket *sock,
2309 				  poll_table *p)
2310 {
2311 	if (!poll_does_not_wait(p)) {
2312 		poll_wait(filp, &sock->wq.wait, p);
2313 		/* We need to be sure we are in sync with the
2314 		 * socket flags modification.
2315 		 *
2316 		 * This memory barrier is paired in the wq_has_sleeper.
2317 		 */
2318 		smp_mb();
2319 	}
2320 }
2321 
skb_set_hash_from_sk(struct sk_buff * skb,struct sock * sk)2322 static inline void skb_set_hash_from_sk(struct sk_buff *skb, struct sock *sk)
2323 {
2324 	/* This pairs with WRITE_ONCE() in sk_set_txhash() */
2325 	u32 txhash = READ_ONCE(sk->sk_txhash);
2326 
2327 	if (txhash) {
2328 		skb->l4_hash = 1;
2329 		skb->hash = txhash;
2330 	}
2331 }
2332 
2333 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk);
2334 
2335 /*
2336  *	Queue a received datagram if it will fit. Stream and sequenced
2337  *	protocols can't normally use this as they need to fit buffers in
2338  *	and play with them.
2339  *
2340  *	Inlined as it's very short and called for pretty much every
2341  *	packet ever received.
2342  */
skb_set_owner_r(struct sk_buff * skb,struct sock * sk)2343 static inline void skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
2344 {
2345 	skb_orphan(skb);
2346 	skb->sk = sk;
2347 	skb->destructor = sock_rfree;
2348 	atomic_add(skb->truesize, &sk->sk_rmem_alloc);
2349 	sk_mem_charge(sk, skb->truesize);
2350 }
2351 
skb_set_owner_sk_safe(struct sk_buff * skb,struct sock * sk)2352 static inline __must_check bool skb_set_owner_sk_safe(struct sk_buff *skb, struct sock *sk)
2353 {
2354 	if (sk && refcount_inc_not_zero(&sk->sk_refcnt)) {
2355 		skb_orphan(skb);
2356 		skb->destructor = sock_efree;
2357 		skb->sk = sk;
2358 		return true;
2359 	}
2360 	return false;
2361 }
2362 
skb_clone_and_charge_r(struct sk_buff * skb,struct sock * sk)2363 static inline struct sk_buff *skb_clone_and_charge_r(struct sk_buff *skb, struct sock *sk)
2364 {
2365 	skb = skb_clone(skb, sk_gfp_mask(sk, GFP_ATOMIC));
2366 	if (skb) {
2367 		if (sk_rmem_schedule(sk, skb, skb->truesize)) {
2368 			skb_set_owner_r(skb, sk);
2369 			return skb;
2370 		}
2371 		__kfree_skb(skb);
2372 	}
2373 	return NULL;
2374 }
2375 
skb_prepare_for_gro(struct sk_buff * skb)2376 static inline void skb_prepare_for_gro(struct sk_buff *skb)
2377 {
2378 	if (skb->destructor != sock_wfree) {
2379 		skb_orphan(skb);
2380 		return;
2381 	}
2382 	skb->slow_gro = 1;
2383 }
2384 
2385 void sk_reset_timer(struct sock *sk, struct timer_list *timer,
2386 		    unsigned long expires);
2387 
2388 void sk_stop_timer(struct sock *sk, struct timer_list *timer);
2389 
2390 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer);
2391 
2392 int __sk_queue_drop_skb(struct sock *sk, struct sk_buff_head *sk_queue,
2393 			struct sk_buff *skb, unsigned int flags,
2394 			void (*destructor)(struct sock *sk,
2395 					   struct sk_buff *skb));
2396 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2397 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
2398 
2399 int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb);
2400 struct sk_buff *sock_dequeue_err_skb(struct sock *sk);
2401 
2402 /*
2403  *	Recover an error report and clear atomically
2404  */
2405 
sock_error(struct sock * sk)2406 static inline int sock_error(struct sock *sk)
2407 {
2408 	int err;
2409 
2410 	/* Avoid an atomic operation for the common case.
2411 	 * This is racy since another cpu/thread can change sk_err under us.
2412 	 */
2413 	if (likely(data_race(!sk->sk_err)))
2414 		return 0;
2415 
2416 	err = xchg(&sk->sk_err, 0);
2417 	return -err;
2418 }
2419 
2420 void sk_error_report(struct sock *sk);
2421 
sock_wspace(struct sock * sk)2422 static inline unsigned long sock_wspace(struct sock *sk)
2423 {
2424 	int amt = 0;
2425 
2426 	if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
2427 		amt = sk->sk_sndbuf - refcount_read(&sk->sk_wmem_alloc);
2428 		if (amt < 0)
2429 			amt = 0;
2430 	}
2431 	return amt;
2432 }
2433 
2434 /* Note:
2435  *  We use sk->sk_wq_raw, from contexts knowing this
2436  *  pointer is not NULL and cannot disappear/change.
2437  */
sk_set_bit(int nr,struct sock * sk)2438 static inline void sk_set_bit(int nr, struct sock *sk)
2439 {
2440 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2441 	    !sock_flag(sk, SOCK_FASYNC))
2442 		return;
2443 
2444 	set_bit(nr, &sk->sk_wq_raw->flags);
2445 }
2446 
sk_clear_bit(int nr,struct sock * sk)2447 static inline void sk_clear_bit(int nr, struct sock *sk)
2448 {
2449 	if ((nr == SOCKWQ_ASYNC_NOSPACE || nr == SOCKWQ_ASYNC_WAITDATA) &&
2450 	    !sock_flag(sk, SOCK_FASYNC))
2451 		return;
2452 
2453 	clear_bit(nr, &sk->sk_wq_raw->flags);
2454 }
2455 
sk_wake_async(const struct sock * sk,int how,int band)2456 static inline void sk_wake_async(const struct sock *sk, int how, int band)
2457 {
2458 	if (sock_flag(sk, SOCK_FASYNC)) {
2459 		rcu_read_lock();
2460 		sock_wake_async(rcu_dereference(sk->sk_wq), how, band);
2461 		rcu_read_unlock();
2462 	}
2463 }
2464 
2465 /* Since sk_{r,w}mem_alloc sums skb->truesize, even a small frame might
2466  * need sizeof(sk_buff) + MTU + padding, unless net driver perform copybreak.
2467  * Note: for send buffers, TCP works better if we can build two skbs at
2468  * minimum.
2469  */
2470 #define TCP_SKB_MIN_TRUESIZE	(2048 + SKB_DATA_ALIGN(sizeof(struct sk_buff)))
2471 
2472 #define SOCK_MIN_SNDBUF		(TCP_SKB_MIN_TRUESIZE * 2)
2473 #define SOCK_MIN_RCVBUF		 TCP_SKB_MIN_TRUESIZE
2474 
sk_stream_moderate_sndbuf(struct sock * sk)2475 static inline void sk_stream_moderate_sndbuf(struct sock *sk)
2476 {
2477 	u32 val;
2478 
2479 	if (sk->sk_userlocks & SOCK_SNDBUF_LOCK)
2480 		return;
2481 
2482 	val = min(sk->sk_sndbuf, sk->sk_wmem_queued >> 1);
2483 
2484 	WRITE_ONCE(sk->sk_sndbuf, max_t(u32, val, SOCK_MIN_SNDBUF));
2485 }
2486 
2487 struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
2488 				    bool force_schedule);
2489 
2490 /**
2491  * sk_page_frag - return an appropriate page_frag
2492  * @sk: socket
2493  *
2494  * Use the per task page_frag instead of the per socket one for
2495  * optimization when we know that we're in process context and own
2496  * everything that's associated with %current.
2497  *
2498  * Both direct reclaim and page faults can nest inside other
2499  * socket operations and end up recursing into sk_page_frag()
2500  * while it's already in use: explicitly avoid task page_frag
2501  * usage if the caller is potentially doing any of them.
2502  * This assumes that page fault handlers use the GFP_NOFS flags.
2503  *
2504  * Return: a per task page_frag if context allows that,
2505  * otherwise a per socket one.
2506  */
sk_page_frag(struct sock * sk)2507 static inline struct page_frag *sk_page_frag(struct sock *sk)
2508 {
2509 	if ((sk->sk_allocation & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC | __GFP_FS)) ==
2510 	    (__GFP_DIRECT_RECLAIM | __GFP_FS))
2511 		return &current->task_frag;
2512 
2513 	return &sk->sk_frag;
2514 }
2515 
2516 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag);
2517 
2518 /*
2519  *	Default write policy as shown to user space via poll/select/SIGIO
2520  */
sock_writeable(const struct sock * sk)2521 static inline bool sock_writeable(const struct sock *sk)
2522 {
2523 	return refcount_read(&sk->sk_wmem_alloc) < (READ_ONCE(sk->sk_sndbuf) >> 1);
2524 }
2525 
gfp_any(void)2526 static inline gfp_t gfp_any(void)
2527 {
2528 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2529 }
2530 
gfp_memcg_charge(void)2531 static inline gfp_t gfp_memcg_charge(void)
2532 {
2533 	return in_softirq() ? GFP_ATOMIC : GFP_KERNEL;
2534 }
2535 
sock_rcvtimeo(const struct sock * sk,bool noblock)2536 static inline long sock_rcvtimeo(const struct sock *sk, bool noblock)
2537 {
2538 	return noblock ? 0 : sk->sk_rcvtimeo;
2539 }
2540 
sock_sndtimeo(const struct sock * sk,bool noblock)2541 static inline long sock_sndtimeo(const struct sock *sk, bool noblock)
2542 {
2543 	return noblock ? 0 : sk->sk_sndtimeo;
2544 }
2545 
sock_rcvlowat(const struct sock * sk,int waitall,int len)2546 static inline int sock_rcvlowat(const struct sock *sk, int waitall, int len)
2547 {
2548 	int v = waitall ? len : min_t(int, READ_ONCE(sk->sk_rcvlowat), len);
2549 
2550 	return v ?: 1;
2551 }
2552 
2553 /* Alas, with timeout socket operations are not restartable.
2554  * Compare this to poll().
2555  */
sock_intr_errno(long timeo)2556 static inline int sock_intr_errno(long timeo)
2557 {
2558 	return timeo == MAX_SCHEDULE_TIMEOUT ? -ERESTARTSYS : -EINTR;
2559 }
2560 
2561 struct sock_skb_cb {
2562 	u32 dropcount;
2563 };
2564 
2565 /* Store sock_skb_cb at the end of skb->cb[] so protocol families
2566  * using skb->cb[] would keep using it directly and utilize its
2567  * alignement guarantee.
2568  */
2569 #define SOCK_SKB_CB_OFFSET ((sizeof_field(struct sk_buff, cb) - \
2570 			    sizeof(struct sock_skb_cb)))
2571 
2572 #define SOCK_SKB_CB(__skb) ((struct sock_skb_cb *)((__skb)->cb + \
2573 			    SOCK_SKB_CB_OFFSET))
2574 
2575 #define sock_skb_cb_check_size(size) \
2576 	BUILD_BUG_ON((size) > SOCK_SKB_CB_OFFSET)
2577 
2578 static inline void
sock_skb_set_dropcount(const struct sock * sk,struct sk_buff * skb)2579 sock_skb_set_dropcount(const struct sock *sk, struct sk_buff *skb)
2580 {
2581 	SOCK_SKB_CB(skb)->dropcount = sock_flag(sk, SOCK_RXQ_OVFL) ?
2582 						atomic_read(&sk->sk_drops) : 0;
2583 }
2584 
sk_drops_add(struct sock * sk,const struct sk_buff * skb)2585 static inline void sk_drops_add(struct sock *sk, const struct sk_buff *skb)
2586 {
2587 	int segs = max_t(u16, 1, skb_shinfo(skb)->gso_segs);
2588 
2589 	atomic_add(segs, &sk->sk_drops);
2590 }
2591 
sock_read_timestamp(struct sock * sk)2592 static inline ktime_t sock_read_timestamp(struct sock *sk)
2593 {
2594 #if BITS_PER_LONG==32
2595 	unsigned int seq;
2596 	ktime_t kt;
2597 
2598 	do {
2599 		seq = read_seqbegin(&sk->sk_stamp_seq);
2600 		kt = sk->sk_stamp;
2601 	} while (read_seqretry(&sk->sk_stamp_seq, seq));
2602 
2603 	return kt;
2604 #else
2605 	return READ_ONCE(sk->sk_stamp);
2606 #endif
2607 }
2608 
sock_write_timestamp(struct sock * sk,ktime_t kt)2609 static inline void sock_write_timestamp(struct sock *sk, ktime_t kt)
2610 {
2611 #if BITS_PER_LONG==32
2612 	write_seqlock(&sk->sk_stamp_seq);
2613 	sk->sk_stamp = kt;
2614 	write_sequnlock(&sk->sk_stamp_seq);
2615 #else
2616 	WRITE_ONCE(sk->sk_stamp, kt);
2617 #endif
2618 }
2619 
2620 void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
2621 			   struct sk_buff *skb);
2622 void __sock_recv_wifi_status(struct msghdr *msg, struct sock *sk,
2623 			     struct sk_buff *skb);
2624 
2625 static inline void
sock_recv_timestamp(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2626 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
2627 {
2628 	ktime_t kt = skb->tstamp;
2629 	struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
2630 
2631 	/*
2632 	 * generate control messages if
2633 	 * - receive time stamping in software requested
2634 	 * - software time stamp available and wanted
2635 	 * - hardware time stamps available and wanted
2636 	 */
2637 	if (sock_flag(sk, SOCK_RCVTSTAMP) ||
2638 	    (sk->sk_tsflags & SOF_TIMESTAMPING_RX_SOFTWARE) ||
2639 	    (kt && sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE) ||
2640 	    (hwtstamps->hwtstamp &&
2641 	     (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)))
2642 		__sock_recv_timestamp(msg, sk, skb);
2643 	else
2644 		sock_write_timestamp(sk, kt);
2645 
2646 	if (sock_flag(sk, SOCK_WIFI_STATUS) && skb->wifi_acked_valid)
2647 		__sock_recv_wifi_status(msg, sk, skb);
2648 }
2649 
2650 void __sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2651 			      struct sk_buff *skb);
2652 
2653 #define SK_DEFAULT_STAMP (-1L * NSEC_PER_SEC)
sock_recv_ts_and_drops(struct msghdr * msg,struct sock * sk,struct sk_buff * skb)2654 static inline void sock_recv_ts_and_drops(struct msghdr *msg, struct sock *sk,
2655 					  struct sk_buff *skb)
2656 {
2657 #define FLAGS_TS_OR_DROPS ((1UL << SOCK_RXQ_OVFL)			| \
2658 			   (1UL << SOCK_RCVTSTAMP))
2659 #define TSFLAGS_ANY	  (SOF_TIMESTAMPING_SOFTWARE			| \
2660 			   SOF_TIMESTAMPING_RAW_HARDWARE)
2661 
2662 	if (sk->sk_flags & FLAGS_TS_OR_DROPS || sk->sk_tsflags & TSFLAGS_ANY)
2663 		__sock_recv_ts_and_drops(msg, sk, skb);
2664 	else if (unlikely(sock_flag(sk, SOCK_TIMESTAMP)))
2665 		sock_write_timestamp(sk, skb->tstamp);
2666 	else if (unlikely(sock_read_timestamp(sk) == SK_DEFAULT_STAMP))
2667 		sock_write_timestamp(sk, 0);
2668 }
2669 
2670 void __sock_tx_timestamp(__u16 tsflags, __u8 *tx_flags);
2671 
2672 /**
2673  * _sock_tx_timestamp - checks whether the outgoing packet is to be time stamped
2674  * @sk:		socket sending this packet
2675  * @tsflags:	timestamping flags to use
2676  * @tx_flags:	completed with instructions for time stamping
2677  * @tskey:      filled in with next sk_tskey (not for TCP, which uses seqno)
2678  *
2679  * Note: callers should take care of initial ``*tx_flags`` value (usually 0)
2680  */
_sock_tx_timestamp(struct sock * sk,__u16 tsflags,__u8 * tx_flags,__u32 * tskey)2681 static inline void _sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2682 				      __u8 *tx_flags, __u32 *tskey)
2683 {
2684 	if (unlikely(tsflags)) {
2685 		__sock_tx_timestamp(tsflags, tx_flags);
2686 		if (tsflags & SOF_TIMESTAMPING_OPT_ID && tskey &&
2687 		    tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
2688 			*tskey = atomic_inc_return(&sk->sk_tskey) - 1;
2689 	}
2690 	if (unlikely(sock_flag(sk, SOCK_WIFI_STATUS)))
2691 		*tx_flags |= SKBTX_WIFI_STATUS;
2692 }
2693 
sock_tx_timestamp(struct sock * sk,__u16 tsflags,__u8 * tx_flags)2694 static inline void sock_tx_timestamp(struct sock *sk, __u16 tsflags,
2695 				     __u8 *tx_flags)
2696 {
2697 	_sock_tx_timestamp(sk, tsflags, tx_flags, NULL);
2698 }
2699 
skb_setup_tx_timestamp(struct sk_buff * skb,__u16 tsflags)2700 static inline void skb_setup_tx_timestamp(struct sk_buff *skb, __u16 tsflags)
2701 {
2702 	_sock_tx_timestamp(skb->sk, tsflags, &skb_shinfo(skb)->tx_flags,
2703 			   &skb_shinfo(skb)->tskey);
2704 }
2705 
2706 DECLARE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key);
2707 /**
2708  * sk_eat_skb - Release a skb if it is no longer needed
2709  * @sk: socket to eat this skb from
2710  * @skb: socket buffer to eat
2711  *
2712  * This routine must be called with interrupts disabled or with the socket
2713  * locked so that the sk_buff queue operation is ok.
2714 */
sk_eat_skb(struct sock * sk,struct sk_buff * skb)2715 static inline void sk_eat_skb(struct sock *sk, struct sk_buff *skb)
2716 {
2717 	__skb_unlink(skb, &sk->sk_receive_queue);
2718 	if (static_branch_unlikely(&tcp_rx_skb_cache_key) &&
2719 	    !sk->sk_rx_skb_cache) {
2720 		sk->sk_rx_skb_cache = skb;
2721 		skb_orphan(skb);
2722 		return;
2723 	}
2724 	__kfree_skb(skb);
2725 }
2726 
2727 static inline
sock_net(const struct sock * sk)2728 struct net *sock_net(const struct sock *sk)
2729 {
2730 	return read_pnet(&sk->sk_net);
2731 }
2732 
2733 static inline
sock_net_set(struct sock * sk,struct net * net)2734 void sock_net_set(struct sock *sk, struct net *net)
2735 {
2736 	write_pnet(&sk->sk_net, net);
2737 }
2738 
2739 static inline bool
skb_sk_is_prefetched(struct sk_buff * skb)2740 skb_sk_is_prefetched(struct sk_buff *skb)
2741 {
2742 #ifdef CONFIG_INET
2743 	return skb->destructor == sock_pfree;
2744 #else
2745 	return false;
2746 #endif /* CONFIG_INET */
2747 }
2748 
2749 /* This helper checks if a socket is a full socket,
2750  * ie _not_ a timewait or request socket.
2751  */
sk_fullsock(const struct sock * sk)2752 static inline bool sk_fullsock(const struct sock *sk)
2753 {
2754 	return (1 << sk->sk_state) & ~(TCPF_TIME_WAIT | TCPF_NEW_SYN_RECV);
2755 }
2756 
2757 static inline bool
sk_is_refcounted(struct sock * sk)2758 sk_is_refcounted(struct sock *sk)
2759 {
2760 	/* Only full sockets have sk->sk_flags. */
2761 	return !sk_fullsock(sk) || !sock_flag(sk, SOCK_RCU_FREE);
2762 }
2763 
2764 /**
2765  * skb_steal_sock - steal a socket from an sk_buff
2766  * @skb: sk_buff to steal the socket from
2767  * @refcounted: is set to true if the socket is reference-counted
2768  */
2769 static inline struct sock *
skb_steal_sock(struct sk_buff * skb,bool * refcounted)2770 skb_steal_sock(struct sk_buff *skb, bool *refcounted)
2771 {
2772 	if (skb->sk) {
2773 		struct sock *sk = skb->sk;
2774 
2775 		*refcounted = true;
2776 		if (skb_sk_is_prefetched(skb))
2777 			*refcounted = sk_is_refcounted(sk);
2778 		skb->destructor = NULL;
2779 		skb->sk = NULL;
2780 		return sk;
2781 	}
2782 	*refcounted = false;
2783 	return NULL;
2784 }
2785 
2786 /* Checks if this SKB belongs to an HW offloaded socket
2787  * and whether any SW fallbacks are required based on dev.
2788  * Check decrypted mark in case skb_orphan() cleared socket.
2789  */
sk_validate_xmit_skb(struct sk_buff * skb,struct net_device * dev)2790 static inline struct sk_buff *sk_validate_xmit_skb(struct sk_buff *skb,
2791 						   struct net_device *dev)
2792 {
2793 #ifdef CONFIG_SOCK_VALIDATE_XMIT
2794 	struct sock *sk = skb->sk;
2795 
2796 	if (sk && sk_fullsock(sk) && sk->sk_validate_xmit_skb) {
2797 		skb = sk->sk_validate_xmit_skb(sk, dev, skb);
2798 #ifdef CONFIG_TLS_DEVICE
2799 	} else if (unlikely(skb->decrypted)) {
2800 		pr_warn_ratelimited("unencrypted skb with no associated socket - dropping\n");
2801 		kfree_skb(skb);
2802 		skb = NULL;
2803 #endif
2804 	}
2805 #endif
2806 
2807 	return skb;
2808 }
2809 
2810 /* This helper checks if a socket is a LISTEN or NEW_SYN_RECV
2811  * SYNACK messages can be attached to either ones (depending on SYNCOOKIE)
2812  */
sk_listener(const struct sock * sk)2813 static inline bool sk_listener(const struct sock *sk)
2814 {
2815 	return (1 << sk->sk_state) & (TCPF_LISTEN | TCPF_NEW_SYN_RECV);
2816 }
2817 
2818 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag);
2819 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len, int level,
2820 		       int type);
2821 
2822 bool sk_ns_capable(const struct sock *sk,
2823 		   struct user_namespace *user_ns, int cap);
2824 bool sk_capable(const struct sock *sk, int cap);
2825 bool sk_net_capable(const struct sock *sk, int cap);
2826 
2827 void sk_get_meminfo(const struct sock *sk, u32 *meminfo);
2828 
2829 /* Take into consideration the size of the struct sk_buff overhead in the
2830  * determination of these values, since that is non-constant across
2831  * platforms.  This makes socket queueing behavior and performance
2832  * not depend upon such differences.
2833  */
2834 #define _SK_MEM_PACKETS		256
2835 #define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
2836 #define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2837 #define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
2838 
2839 extern __u32 sysctl_wmem_max;
2840 extern __u32 sysctl_rmem_max;
2841 
2842 extern int sysctl_tstamp_allow_data;
2843 extern int sysctl_optmem_max;
2844 
2845 extern __u32 sysctl_wmem_default;
2846 extern __u32 sysctl_rmem_default;
2847 
2848 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2849 DECLARE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2850 
sk_get_wmem0(const struct sock * sk,const struct proto * proto)2851 static inline int sk_get_wmem0(const struct sock *sk, const struct proto *proto)
2852 {
2853 	/* Does this proto have per netns sysctl_wmem ? */
2854 	if (proto->sysctl_wmem_offset)
2855 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_wmem_offset));
2856 
2857 	return READ_ONCE(*proto->sysctl_wmem);
2858 }
2859 
sk_get_rmem0(const struct sock * sk,const struct proto * proto)2860 static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto)
2861 {
2862 	/* Does this proto have per netns sysctl_rmem ? */
2863 	if (proto->sysctl_rmem_offset)
2864 		return READ_ONCE(*(int *)((void *)sock_net(sk) + proto->sysctl_rmem_offset));
2865 
2866 	return READ_ONCE(*proto->sysctl_rmem);
2867 }
2868 
2869 /* Default TCP Small queue budget is ~1 ms of data (1sec >> 10)
2870  * Some wifi drivers need to tweak it to get more chunks.
2871  * They can use this helper from their ndo_start_xmit()
2872  */
sk_pacing_shift_update(struct sock * sk,int val)2873 static inline void sk_pacing_shift_update(struct sock *sk, int val)
2874 {
2875 	if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val)
2876 		return;
2877 	WRITE_ONCE(sk->sk_pacing_shift, val);
2878 }
2879 
2880 /* if a socket is bound to a device, check that the given device
2881  * index is either the same or that the socket is bound to an L3
2882  * master device and the given device index is also enslaved to
2883  * that L3 master
2884  */
sk_dev_equal_l3scope(struct sock * sk,int dif)2885 static inline bool sk_dev_equal_l3scope(struct sock *sk, int dif)
2886 {
2887 	int mdif;
2888 
2889 	if (!sk->sk_bound_dev_if || sk->sk_bound_dev_if == dif)
2890 		return true;
2891 
2892 	mdif = l3mdev_master_ifindex_by_index(sock_net(sk), dif);
2893 	if (mdif && mdif == sk->sk_bound_dev_if)
2894 		return true;
2895 
2896 	return false;
2897 }
2898 
2899 void sock_def_readable(struct sock *sk);
2900 
2901 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk);
2902 void sock_set_timestamp(struct sock *sk, int optname, bool valbool);
2903 int sock_set_timestamping(struct sock *sk, int optname,
2904 			  struct so_timestamping timestamping);
2905 
2906 void sock_enable_timestamps(struct sock *sk);
2907 void sock_no_linger(struct sock *sk);
2908 void sock_set_keepalive(struct sock *sk);
2909 void sock_set_priority(struct sock *sk, u32 priority);
2910 void sock_set_rcvbuf(struct sock *sk, int val);
2911 void sock_set_mark(struct sock *sk, u32 val);
2912 void sock_set_reuseaddr(struct sock *sk);
2913 void sock_set_reuseport(struct sock *sk);
2914 void sock_set_sndtimeo(struct sock *sk, s64 secs);
2915 
2916 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len);
2917 
sk_is_readable(struct sock * sk)2918 static inline bool sk_is_readable(struct sock *sk)
2919 {
2920 	if (sk->sk_prot->sock_is_readable)
2921 		return sk->sk_prot->sock_is_readable(sk);
2922 	return false;
2923 }
2924 #endif	/* _SOCK_H */
2925