xref: /linux/net/core/sock.c (revision db30e412b7f543d00396ab27f690608cad06aa97)
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  *		Generic socket support routines. Memory allocators, socket lock/release
8  *		handler for protocols to use and generic option handler.
9  *
10  * Authors:	Ross Biro
11  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12  *		Florian La Roche, <flla@stud.uni-sb.de>
13  *		Alan Cox, <A.Cox@swansea.ac.uk>
14  *
15  * Fixes:
16  *		Alan Cox	: 	Numerous verify_area() problems
17  *		Alan Cox	:	Connecting on a connecting socket
18  *					now returns an error for tcp.
19  *		Alan Cox	:	sock->protocol is set correctly.
20  *					and is not sometimes left as 0.
21  *		Alan Cox	:	connect handles icmp errors on a
22  *					connect properly. Unfortunately there
23  *					is a restart syscall nasty there. I
24  *					can't match BSD without hacking the C
25  *					library. Ideas urgently sought!
26  *		Alan Cox	:	Disallow bind() to addresses that are
27  *					not ours - especially broadcast ones!!
28  *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
29  *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
30  *					instead they leave that for the DESTROY timer.
31  *		Alan Cox	:	Clean up error flag in accept
32  *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
33  *					was buggy. Put a remove_sock() in the handler
34  *					for memory when we hit 0. Also altered the timer
35  *					code. The ACK stuff can wait and needs major
36  *					TCP layer surgery.
37  *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
38  *					and fixed timer/inet_bh race.
39  *		Alan Cox	:	Added zapped flag for TCP
40  *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
41  *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42  *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
43  *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
44  *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45  *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
46  *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
47  *	Pauline Middelink	:	identd support
48  *		Alan Cox	:	Fixed connect() taking signals I think.
49  *		Alan Cox	:	SO_LINGER supported
50  *		Alan Cox	:	Error reporting fixes
51  *		Anonymous	:	inet_create tidied up (sk->reuse setting)
52  *		Alan Cox	:	inet sockets don't set sk->type!
53  *		Alan Cox	:	Split socket option code
54  *		Alan Cox	:	Callbacks
55  *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
56  *		Alex		:	Removed restriction on inet fioctl
57  *		Alan Cox	:	Splitting INET from NET core
58  *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
59  *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
60  *		Alan Cox	:	Split IP from generic code
61  *		Alan Cox	:	New kfree_skbmem()
62  *		Alan Cox	:	Make SO_DEBUG superuser only.
63  *		Alan Cox	:	Allow anyone to clear SO_DEBUG
64  *					(compatibility fix)
65  *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
66  *		Alan Cox	:	Allocator for a socket is settable.
67  *		Alan Cox	:	SO_ERROR includes soft errors.
68  *		Alan Cox	:	Allow NULL arguments on some SO_ opts
69  *		Alan Cox	: 	Generic socket allocation to make hooks
70  *					easier (suggested by Craig Metz).
71  *		Michael Pall	:	SO_ERROR returns positive errno again
72  *              Steve Whitehouse:       Added default destructor to free
73  *                                      protocol private data.
74  *              Steve Whitehouse:       Added various other default routines
75  *                                      common to several socket families.
76  *              Chris Evans     :       Call suser() check last on F_SETOWN
77  *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78  *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
79  *		Andi Kleen	:	Fix write_space callback
80  *		Chris Evans	:	Security fixes - signedness again
81  *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
82  *
83  * To Fix:
84  */
85 
86 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
87 
88 #include <linux/unaligned.h>
89 #include <linux/capability.h>
90 #include <linux/errno.h>
91 #include <linux/errqueue.h>
92 #include <linux/types.h>
93 #include <linux/socket.h>
94 #include <linux/in.h>
95 #include <linux/kernel.h>
96 #include <linux/module.h>
97 #include <linux/proc_fs.h>
98 #include <linux/seq_file.h>
99 #include <linux/sched.h>
100 #include <linux/sched/mm.h>
101 #include <linux/timer.h>
102 #include <linux/string.h>
103 #include <linux/sockios.h>
104 #include <linux/net.h>
105 #include <linux/mm.h>
106 #include <linux/slab.h>
107 #include <linux/interrupt.h>
108 #include <linux/poll.h>
109 #include <linux/tcp.h>
110 #include <linux/udp.h>
111 #include <linux/init.h>
112 #include <linux/highmem.h>
113 #include <linux/user_namespace.h>
114 #include <linux/static_key.h>
115 #include <linux/memcontrol.h>
116 #include <linux/prefetch.h>
117 #include <linux/compat.h>
118 #include <linux/mroute.h>
119 #include <linux/mroute6.h>
120 #include <linux/icmpv6.h>
121 
122 #include <linux/uaccess.h>
123 
124 #include <linux/netdevice.h>
125 #include <net/protocol.h>
126 #include <linux/skbuff.h>
127 #include <linux/skbuff_ref.h>
128 #include <net/net_namespace.h>
129 #include <net/request_sock.h>
130 #include <net/sock.h>
131 #include <net/proto_memory.h>
132 #include <linux/net_tstamp.h>
133 #include <net/xfrm.h>
134 #include <linux/ipsec.h>
135 #include <net/cls_cgroup.h>
136 #include <net/netprio_cgroup.h>
137 #include <linux/sock_diag.h>
138 
139 #include <linux/filter.h>
140 #include <net/sock_reuseport.h>
141 #include <net/bpf_sk_storage.h>
142 
143 #include <trace/events/sock.h>
144 
145 #include <net/tcp.h>
146 #include <net/busy_poll.h>
147 #include <net/phonet/phonet.h>
148 
149 #include <linux/ethtool.h>
150 
151 #include <uapi/linux/pidfd.h>
152 
153 #include "dev.h"
154 
155 static DEFINE_MUTEX(proto_list_mutex);
156 static LIST_HEAD(proto_list);
157 
158 static void sock_def_write_space_wfree(struct sock *sk, int wmem_alloc);
159 static void sock_def_write_space(struct sock *sk);
160 
161 /**
162  * sk_ns_capable - General socket capability test
163  * @sk: Socket to use a capability on or through
164  * @user_ns: The user namespace of the capability to use
165  * @cap: The capability to use
166  *
167  * Test to see if the opener of the socket had when the socket was
168  * created and the current process has the capability @cap in the user
169  * namespace @user_ns.
170  */
171 bool sk_ns_capable(const struct sock *sk,
172 		   struct user_namespace *user_ns, int cap)
173 {
174 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
175 		ns_capable(user_ns, cap);
176 }
177 EXPORT_SYMBOL(sk_ns_capable);
178 
179 /**
180  * sk_capable - Socket global capability test
181  * @sk: Socket to use a capability on or through
182  * @cap: The global capability to use
183  *
184  * Test to see if the opener of the socket had when the socket was
185  * created and the current process has the capability @cap in all user
186  * namespaces.
187  */
188 bool sk_capable(const struct sock *sk, int cap)
189 {
190 	return sk_ns_capable(sk, &init_user_ns, cap);
191 }
192 EXPORT_SYMBOL(sk_capable);
193 
194 /**
195  * sk_net_capable - Network namespace socket capability test
196  * @sk: Socket to use a capability on or through
197  * @cap: The capability to use
198  *
199  * Test to see if the opener of the socket had when the socket was created
200  * and the current process has the capability @cap over the network namespace
201  * the socket is a member of.
202  */
203 bool sk_net_capable(const struct sock *sk, int cap)
204 {
205 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
206 }
207 EXPORT_SYMBOL(sk_net_capable);
208 
209 /*
210  * Each address family might have different locking rules, so we have
211  * one slock key per address family and separate keys for internal and
212  * userspace sockets.
213  */
214 static struct lock_class_key af_family_keys[AF_MAX];
215 static struct lock_class_key af_family_kern_keys[AF_MAX];
216 static struct lock_class_key af_family_slock_keys[AF_MAX];
217 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
218 
219 /*
220  * Make lock validator output more readable. (we pre-construct these
221  * strings build-time, so that runtime initialization of socket
222  * locks is fast):
223  */
224 
225 #define _sock_locks(x)						  \
226   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
227   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
228   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
229   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
230   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
231   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
232   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
233   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
234   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
235   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
236   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
237   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
238   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
239   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
240   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
241   x "AF_MCTP"  , \
242   x "AF_MAX"
243 
244 static const char *const af_family_key_strings[AF_MAX+1] = {
245 	_sock_locks("sk_lock-")
246 };
247 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
248 	_sock_locks("slock-")
249 };
250 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
251 	_sock_locks("clock-")
252 };
253 
254 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
255 	_sock_locks("k-sk_lock-")
256 };
257 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
258 	_sock_locks("k-slock-")
259 };
260 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
261 	_sock_locks("k-clock-")
262 };
263 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
264 	_sock_locks("rlock-")
265 };
266 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
267 	_sock_locks("wlock-")
268 };
269 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
270 	_sock_locks("elock-")
271 };
272 
273 /*
274  * sk_callback_lock and sk queues locking rules are per-address-family,
275  * so split the lock classes by using a per-AF key:
276  */
277 static struct lock_class_key af_callback_keys[AF_MAX];
278 static struct lock_class_key af_rlock_keys[AF_MAX];
279 static struct lock_class_key af_wlock_keys[AF_MAX];
280 static struct lock_class_key af_elock_keys[AF_MAX];
281 static struct lock_class_key af_kern_callback_keys[AF_MAX];
282 
283 /* Run time adjustable parameters. */
284 __u32 sysctl_wmem_max __read_mostly = 4 << 20;
285 EXPORT_SYMBOL(sysctl_wmem_max);
286 __u32 sysctl_rmem_max __read_mostly = 4 << 20;
287 EXPORT_SYMBOL(sysctl_rmem_max);
288 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_DEFAULT;
289 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_DEFAULT;
290 
291 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
292 EXPORT_SYMBOL_GPL(memalloc_socks_key);
293 
294 /**
295  * sk_set_memalloc - sets %SOCK_MEMALLOC
296  * @sk: socket to set it on
297  *
298  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
299  * It's the responsibility of the admin to adjust min_free_kbytes
300  * to meet the requirements
301  */
302 void sk_set_memalloc(struct sock *sk)
303 {
304 	sock_set_flag(sk, SOCK_MEMALLOC);
305 	sk->sk_allocation |= __GFP_MEMALLOC;
306 	static_branch_inc(&memalloc_socks_key);
307 }
308 EXPORT_SYMBOL_GPL(sk_set_memalloc);
309 
310 void sk_clear_memalloc(struct sock *sk)
311 {
312 	sock_reset_flag(sk, SOCK_MEMALLOC);
313 	sk->sk_allocation &= ~__GFP_MEMALLOC;
314 	static_branch_dec(&memalloc_socks_key);
315 
316 	/*
317 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
318 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
319 	 * it has rmem allocations due to the last swapfile being deactivated
320 	 * but there is a risk that the socket is unusable due to exceeding
321 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
322 	 */
323 	sk_mem_reclaim(sk);
324 }
325 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
326 
327 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
328 {
329 	int ret;
330 	unsigned int noreclaim_flag;
331 
332 	/* these should have been dropped before queueing */
333 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
334 
335 	noreclaim_flag = memalloc_noreclaim_save();
336 	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
337 				 tcp_v6_do_rcv,
338 				 tcp_v4_do_rcv,
339 				 sk, skb);
340 	memalloc_noreclaim_restore(noreclaim_flag);
341 
342 	return ret;
343 }
344 EXPORT_SYMBOL(__sk_backlog_rcv);
345 
346 void sk_error_report(struct sock *sk)
347 {
348 	sk->sk_error_report(sk);
349 
350 	switch (sk->sk_family) {
351 	case AF_INET:
352 		fallthrough;
353 	case AF_INET6:
354 		trace_inet_sk_error_report(sk);
355 		break;
356 	default:
357 		break;
358 	}
359 }
360 EXPORT_SYMBOL(sk_error_report);
361 
362 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
363 {
364 	struct __kernel_sock_timeval tv;
365 
366 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
367 		tv.tv_sec = 0;
368 		tv.tv_usec = 0;
369 	} else {
370 		tv.tv_sec = timeo / HZ;
371 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
372 	}
373 
374 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
375 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
376 		*(struct old_timeval32 *)optval = tv32;
377 		return sizeof(tv32);
378 	}
379 
380 	if (old_timeval) {
381 		struct __kernel_old_timeval old_tv;
382 		old_tv.tv_sec = tv.tv_sec;
383 		old_tv.tv_usec = tv.tv_usec;
384 		*(struct __kernel_old_timeval *)optval = old_tv;
385 		return sizeof(old_tv);
386 	}
387 
388 	*(struct __kernel_sock_timeval *)optval = tv;
389 	return sizeof(tv);
390 }
391 EXPORT_SYMBOL(sock_get_timeout);
392 
393 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
394 			   sockptr_t optval, int optlen, bool old_timeval)
395 {
396 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
397 		struct old_timeval32 tv32;
398 
399 		if (optlen < sizeof(tv32))
400 			return -EINVAL;
401 
402 		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
403 			return -EFAULT;
404 		tv->tv_sec = tv32.tv_sec;
405 		tv->tv_usec = tv32.tv_usec;
406 	} else if (old_timeval) {
407 		struct __kernel_old_timeval old_tv;
408 
409 		if (optlen < sizeof(old_tv))
410 			return -EINVAL;
411 		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
412 			return -EFAULT;
413 		tv->tv_sec = old_tv.tv_sec;
414 		tv->tv_usec = old_tv.tv_usec;
415 	} else {
416 		if (optlen < sizeof(*tv))
417 			return -EINVAL;
418 		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
419 			return -EFAULT;
420 	}
421 
422 	return 0;
423 }
424 EXPORT_SYMBOL(sock_copy_user_timeval);
425 
426 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
427 			    bool old_timeval)
428 {
429 	struct __kernel_sock_timeval tv;
430 	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
431 	long val;
432 
433 	if (err)
434 		return err;
435 
436 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
437 		return -EDOM;
438 
439 	if (tv.tv_sec < 0) {
440 		static int warned __read_mostly;
441 
442 		WRITE_ONCE(*timeo_p, 0);
443 		if (warned < 10 && net_ratelimit()) {
444 			warned++;
445 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
446 				__func__, current->comm, task_pid_nr(current));
447 		}
448 		return 0;
449 	}
450 	val = MAX_SCHEDULE_TIMEOUT;
451 	if ((tv.tv_sec || tv.tv_usec) &&
452 	    (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))
453 		val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,
454 						    USEC_PER_SEC / HZ);
455 	WRITE_ONCE(*timeo_p, val);
456 	return 0;
457 }
458 
459 static bool sk_set_prio_allowed(const struct sock *sk, int val)
460 {
461 	return ((val >= TC_PRIO_BESTEFFORT && val <= TC_PRIO_INTERACTIVE) ||
462 		sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
463 		sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN));
464 }
465 
466 static bool sock_needs_netstamp(const struct sock *sk)
467 {
468 	switch (sk->sk_family) {
469 	case AF_UNSPEC:
470 	case AF_UNIX:
471 		return false;
472 	default:
473 		return true;
474 	}
475 }
476 
477 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
478 {
479 	if (sk->sk_flags & flags) {
480 		sk->sk_flags &= ~flags;
481 		if (sock_needs_netstamp(sk) &&
482 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
483 			net_disable_timestamp();
484 	}
485 }
486 
487 
488 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
489 {
490 	unsigned long flags;
491 	struct sk_buff_head *list = &sk->sk_receive_queue;
492 
493 	if (atomic_read(&sk->sk_rmem_alloc) >= READ_ONCE(sk->sk_rcvbuf)) {
494 		sk_drops_inc(sk);
495 		trace_sock_rcvqueue_full(sk, skb);
496 		return -ENOMEM;
497 	}
498 
499 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
500 		sk_drops_inc(sk);
501 		return -ENOBUFS;
502 	}
503 
504 	skb->dev = NULL;
505 	skb_set_owner_r(skb, sk);
506 
507 	/* we escape from rcu protected region, make sure we dont leak
508 	 * a norefcounted dst
509 	 */
510 	skb_dst_force(skb);
511 
512 	spin_lock_irqsave(&list->lock, flags);
513 	sock_skb_set_dropcount(sk, skb);
514 	__skb_queue_tail(list, skb);
515 	spin_unlock_irqrestore(&list->lock, flags);
516 
517 	if (!sock_flag(sk, SOCK_DEAD))
518 		sk->sk_data_ready(sk);
519 	return 0;
520 }
521 EXPORT_SYMBOL(__sock_queue_rcv_skb);
522 
523 enum skb_drop_reason
524 sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb)
525 {
526 	enum skb_drop_reason drop_reason;
527 	int err;
528 
529 	drop_reason = sk_filter_reason(sk, skb);
530 	if (drop_reason)
531 		return drop_reason;
532 
533 	err = __sock_queue_rcv_skb(sk, skb);
534 	switch (err) {
535 	case -ENOMEM:
536 		return SKB_DROP_REASON_SOCKET_RCVBUFF;
537 	case -ENOBUFS:
538 		return SKB_DROP_REASON_PROTO_MEM;
539 	}
540 	return SKB_NOT_DROPPED_YET;
541 }
542 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
543 
544 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
545 		     const int nested, unsigned int trim_cap, bool refcounted)
546 {
547 	enum skb_drop_reason reason;
548 	int rc = NET_RX_SUCCESS;
549 	int err;
550 
551 	reason = sk_filter_trim_cap(sk, skb, trim_cap);
552 	if (reason)
553 		goto discard_and_relse;
554 
555 	skb->dev = NULL;
556 
557 	if (sk_rcvqueues_full(sk, READ_ONCE(sk->sk_rcvbuf))) {
558 		sk_drops_inc(sk);
559 		reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
560 		goto discard_and_relse;
561 	}
562 	if (nested)
563 		bh_lock_sock_nested(sk);
564 	else
565 		bh_lock_sock(sk);
566 	if (!sock_owned_by_user(sk)) {
567 		/*
568 		 * trylock + unlock semantics:
569 		 */
570 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
571 
572 		rc = sk_backlog_rcv(sk, skb);
573 
574 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
575 	} else if ((err = sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf)))) {
576 		bh_unlock_sock(sk);
577 		if (err == -ENOMEM)
578 			reason = SKB_DROP_REASON_PFMEMALLOC;
579 		if (err == -ENOBUFS)
580 			reason = SKB_DROP_REASON_SOCKET_BACKLOG;
581 		sk_drops_inc(sk);
582 		goto discard_and_relse;
583 	}
584 
585 	bh_unlock_sock(sk);
586 out:
587 	if (refcounted)
588 		sock_put(sk);
589 	return rc;
590 discard_and_relse:
591 	sk_skb_reason_drop(sk, skb, reason);
592 	goto out;
593 }
594 EXPORT_SYMBOL(__sk_receive_skb);
595 
596 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
597 							  u32));
598 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
599 							   u32));
600 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
601 {
602 	struct dst_entry *dst = __sk_dst_get(sk);
603 
604 	if (dst && READ_ONCE(dst->obsolete) &&
605 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
606 			       dst, cookie) == NULL) {
607 		sk_tx_queue_clear(sk);
608 		WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
609 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
610 		dst_release(dst);
611 		return NULL;
612 	}
613 
614 	return dst;
615 }
616 EXPORT_SYMBOL(__sk_dst_check);
617 
618 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
619 {
620 	struct dst_entry *dst = sk_dst_get(sk);
621 
622 	if (dst && READ_ONCE(dst->obsolete) &&
623 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
624 			       dst, cookie) == NULL) {
625 		sk_dst_reset(sk);
626 		dst_release(dst);
627 		return NULL;
628 	}
629 
630 	return dst;
631 }
632 EXPORT_SYMBOL(sk_dst_check);
633 
634 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
635 {
636 	int ret = -ENOPROTOOPT;
637 #ifdef CONFIG_NETDEVICES
638 	struct net *net = sock_net(sk);
639 
640 	/* Sorry... */
641 	ret = -EPERM;
642 	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
643 		goto out;
644 
645 	ret = -EINVAL;
646 	if (ifindex < 0)
647 		goto out;
648 
649 	/* Paired with all READ_ONCE() done locklessly. */
650 	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
651 
652 	if (sk->sk_prot->rehash)
653 		sk->sk_prot->rehash(sk);
654 	sk_dst_reset(sk);
655 
656 	ret = 0;
657 
658 out:
659 #endif
660 
661 	return ret;
662 }
663 
664 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
665 {
666 	int ret;
667 
668 	if (lock_sk)
669 		lock_sock(sk);
670 	ret = sock_bindtoindex_locked(sk, ifindex);
671 	if (lock_sk)
672 		release_sock(sk);
673 
674 	return ret;
675 }
676 EXPORT_SYMBOL(sock_bindtoindex);
677 
678 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
679 {
680 	int ret = -ENOPROTOOPT;
681 #ifdef CONFIG_NETDEVICES
682 	struct net *net = sock_net(sk);
683 	char devname[IFNAMSIZ];
684 	int index;
685 
686 	ret = -EINVAL;
687 	if (optlen < 0)
688 		goto out;
689 
690 	/* Bind this socket to a particular device like "eth0",
691 	 * as specified in the passed interface name. If the
692 	 * name is "" or the option length is zero the socket
693 	 * is not bound.
694 	 */
695 	if (optlen > IFNAMSIZ - 1)
696 		optlen = IFNAMSIZ - 1;
697 	memset(devname, 0, sizeof(devname));
698 
699 	ret = -EFAULT;
700 	if (copy_from_sockptr(devname, optval, optlen))
701 		goto out;
702 
703 	index = 0;
704 	if (devname[0] != '\0') {
705 		struct net_device *dev;
706 
707 		rcu_read_lock();
708 		dev = dev_get_by_name_rcu(net, devname);
709 		if (dev)
710 			index = dev->ifindex;
711 		rcu_read_unlock();
712 		ret = -ENODEV;
713 		if (!dev)
714 			goto out;
715 	}
716 
717 	sockopt_lock_sock(sk);
718 	ret = sock_bindtoindex_locked(sk, index);
719 	sockopt_release_sock(sk);
720 out:
721 #endif
722 
723 	return ret;
724 }
725 
726 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
727 				sockptr_t optlen, int len)
728 {
729 	int ret = -ENOPROTOOPT;
730 #ifdef CONFIG_NETDEVICES
731 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
732 	struct net *net = sock_net(sk);
733 	char devname[IFNAMSIZ];
734 
735 	if (bound_dev_if == 0) {
736 		len = 0;
737 		goto zero;
738 	}
739 
740 	ret = -EINVAL;
741 	if (len < IFNAMSIZ)
742 		goto out;
743 
744 	ret = netdev_get_name(net, devname, bound_dev_if);
745 	if (ret)
746 		goto out;
747 
748 	len = strlen(devname) + 1;
749 
750 	ret = -EFAULT;
751 	if (copy_to_sockptr(optval, devname, len))
752 		goto out;
753 
754 zero:
755 	ret = -EFAULT;
756 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
757 		goto out;
758 
759 	ret = 0;
760 
761 out:
762 #endif
763 
764 	return ret;
765 }
766 
767 bool sk_mc_loop(const struct sock *sk)
768 {
769 	if (dev_recursion_level())
770 		return false;
771 	if (!sk)
772 		return true;
773 	/* IPV6_ADDRFORM can change sk->sk_family under us. */
774 	switch (READ_ONCE(sk->sk_family)) {
775 	case AF_INET:
776 		return inet_test_bit(MC_LOOP, sk);
777 #if IS_ENABLED(CONFIG_IPV6)
778 	case AF_INET6:
779 		return inet6_test_bit(MC6_LOOP, sk);
780 #endif
781 	}
782 	WARN_ON_ONCE(1);
783 	return true;
784 }
785 EXPORT_SYMBOL(sk_mc_loop);
786 
787 void sock_set_reuseaddr(struct sock *sk)
788 {
789 	lock_sock(sk);
790 	sk->sk_reuse = SK_CAN_REUSE;
791 	release_sock(sk);
792 }
793 EXPORT_SYMBOL(sock_set_reuseaddr);
794 
795 void sock_set_reuseport(struct sock *sk)
796 {
797 	lock_sock(sk);
798 	sk->sk_reuseport = true;
799 	release_sock(sk);
800 }
801 EXPORT_SYMBOL(sock_set_reuseport);
802 
803 void sock_no_linger(struct sock *sk)
804 {
805 	lock_sock(sk);
806 	WRITE_ONCE(sk->sk_lingertime, 0);
807 	sock_set_flag(sk, SOCK_LINGER);
808 	release_sock(sk);
809 }
810 EXPORT_SYMBOL(sock_no_linger);
811 
812 void sock_set_priority(struct sock *sk, u32 priority)
813 {
814 	WRITE_ONCE(sk->sk_priority, priority);
815 }
816 EXPORT_SYMBOL(sock_set_priority);
817 
818 void sock_set_sndtimeo(struct sock *sk, s64 secs)
819 {
820 	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
821 		WRITE_ONCE(sk->sk_sndtimeo, secs * HZ);
822 	else
823 		WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT);
824 }
825 EXPORT_SYMBOL(sock_set_sndtimeo);
826 
827 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
828 {
829 	sock_valbool_flag(sk, SOCK_RCVTSTAMP, val);
830 	sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, val && ns);
831 	if (val)  {
832 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
833 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
834 	}
835 }
836 
837 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
838 {
839 	switch (optname) {
840 	case SO_TIMESTAMP_OLD:
841 		__sock_set_timestamps(sk, valbool, false, false);
842 		break;
843 	case SO_TIMESTAMP_NEW:
844 		__sock_set_timestamps(sk, valbool, true, false);
845 		break;
846 	case SO_TIMESTAMPNS_OLD:
847 		__sock_set_timestamps(sk, valbool, false, true);
848 		break;
849 	case SO_TIMESTAMPNS_NEW:
850 		__sock_set_timestamps(sk, valbool, true, true);
851 		break;
852 	}
853 }
854 
855 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
856 {
857 	struct net *net = sock_net(sk);
858 	struct net_device *dev = NULL;
859 	bool match = false;
860 	int *vclock_index;
861 	int i, num;
862 
863 	if (sk->sk_bound_dev_if)
864 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
865 
866 	if (!dev) {
867 		pr_err("%s: sock not bind to device\n", __func__);
868 		return -EOPNOTSUPP;
869 	}
870 
871 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
872 	dev_put(dev);
873 
874 	for (i = 0; i < num; i++) {
875 		if (*(vclock_index + i) == phc_index) {
876 			match = true;
877 			break;
878 		}
879 	}
880 
881 	if (num > 0)
882 		kfree(vclock_index);
883 
884 	if (!match)
885 		return -EINVAL;
886 
887 	WRITE_ONCE(sk->sk_bind_phc, phc_index);
888 
889 	return 0;
890 }
891 
892 int sock_set_timestamping(struct sock *sk, int optname,
893 			  struct so_timestamping timestamping)
894 {
895 	int val = timestamping.flags;
896 	int ret;
897 
898 	if (val & ~SOF_TIMESTAMPING_MASK)
899 		return -EINVAL;
900 
901 	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
902 	    !(val & SOF_TIMESTAMPING_OPT_ID))
903 		return -EINVAL;
904 
905 	if (val & SOF_TIMESTAMPING_OPT_ID &&
906 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
907 		if (sk_is_tcp(sk)) {
908 			if ((1 << sk->sk_state) &
909 			    (TCPF_CLOSE | TCPF_LISTEN))
910 				return -EINVAL;
911 			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
912 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
913 			else
914 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
915 		} else {
916 			atomic_set(&sk->sk_tskey, 0);
917 		}
918 	}
919 
920 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
921 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
922 		return -EINVAL;
923 
924 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
925 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
926 		if (ret)
927 			return ret;
928 	}
929 
930 	WRITE_ONCE(sk->sk_tsflags, val);
931 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
932 	sock_valbool_flag(sk, SOCK_TIMESTAMPING_ANY, !!(val & TSFLAGS_ANY));
933 
934 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
935 		sock_enable_timestamp(sk,
936 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
937 	else
938 		sock_disable_timestamp(sk,
939 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
940 	return 0;
941 }
942 
943 #if defined(CONFIG_CGROUP_BPF)
944 void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op)
945 {
946 	struct bpf_sock_ops_kern sock_ops;
947 
948 	memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp));
949 	sock_ops.op = op;
950 	sock_ops.is_fullsock = 1;
951 	sock_ops.sk = sk;
952 	bpf_skops_init_skb(&sock_ops, skb, 0);
953 	__cgroup_bpf_run_filter_sock_ops(sk, &sock_ops, CGROUP_SOCK_OPS);
954 }
955 #endif
956 
957 void sock_set_keepalive(struct sock *sk)
958 {
959 	lock_sock(sk);
960 	if (sk->sk_prot->keepalive)
961 		sk->sk_prot->keepalive(sk, true);
962 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
963 	release_sock(sk);
964 }
965 EXPORT_SYMBOL(sock_set_keepalive);
966 
967 static void __sock_set_rcvbuf(struct sock *sk, int val)
968 {
969 	struct socket *sock = sk->sk_socket;
970 
971 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
972 	 * as a negative value.
973 	 */
974 	val = min_t(int, val, INT_MAX / 2);
975 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
976 
977 	/* We double it on the way in to account for "struct sk_buff" etc.
978 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
979 	 * will allow that much actual data to be received on that socket.
980 	 *
981 	 * Applications are unaware that "struct sk_buff" and other overheads
982 	 * allocate from the receive buffer during socket buffer allocation.
983 	 *
984 	 * And after considering the possible alternatives, returning the value
985 	 * we actually used in getsockopt is the most desirable behavior.
986 	 */
987 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
988 
989 	if (sock) {
990 		const struct proto_ops *ops = READ_ONCE(sock->ops);
991 
992 		if (ops->set_rcvbuf)
993 			ops->set_rcvbuf(sk, sk->sk_rcvbuf);
994 	}
995 }
996 
997 void sock_set_rcvbuf(struct sock *sk, int val)
998 {
999 	lock_sock(sk);
1000 	__sock_set_rcvbuf(sk, val);
1001 	release_sock(sk);
1002 }
1003 EXPORT_SYMBOL(sock_set_rcvbuf);
1004 
1005 static void __sock_set_mark(struct sock *sk, u32 val)
1006 {
1007 	if (val != sk->sk_mark) {
1008 		WRITE_ONCE(sk->sk_mark, val);
1009 		sk_dst_reset(sk);
1010 	}
1011 }
1012 
1013 void sock_set_mark(struct sock *sk, u32 val)
1014 {
1015 	lock_sock(sk);
1016 	__sock_set_mark(sk, val);
1017 	release_sock(sk);
1018 }
1019 EXPORT_SYMBOL(sock_set_mark);
1020 
1021 static void sock_release_reserved_memory(struct sock *sk, int bytes)
1022 {
1023 	/* Round down bytes to multiple of pages */
1024 	bytes = round_down(bytes, PAGE_SIZE);
1025 
1026 	WARN_ON(bytes > sk->sk_reserved_mem);
1027 	WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes);
1028 	sk_mem_reclaim(sk);
1029 }
1030 
1031 static int sock_reserve_memory(struct sock *sk, int bytes)
1032 {
1033 	long allocated;
1034 	bool charged;
1035 	int pages;
1036 
1037 	if (!mem_cgroup_sk_enabled(sk) || !sk_has_account(sk))
1038 		return -EOPNOTSUPP;
1039 
1040 	if (!bytes)
1041 		return 0;
1042 
1043 	pages = sk_mem_pages(bytes);
1044 
1045 	/* pre-charge to memcg */
1046 	charged = mem_cgroup_sk_charge(sk, pages,
1047 				       GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1048 	if (!charged)
1049 		return -ENOMEM;
1050 
1051 	if (sk->sk_bypass_prot_mem)
1052 		goto success;
1053 
1054 	/* pre-charge to forward_alloc */
1055 	sk_memory_allocated_add(sk, pages);
1056 	allocated = sk_memory_allocated(sk);
1057 
1058 	/* If the system goes into memory pressure with this
1059 	 * precharge, give up and return error.
1060 	 */
1061 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1062 		sk_memory_allocated_sub(sk, pages);
1063 		mem_cgroup_sk_uncharge(sk, pages);
1064 		return -ENOMEM;
1065 	}
1066 
1067 success:
1068 	sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1069 
1070 	WRITE_ONCE(sk->sk_reserved_mem,
1071 		   sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1072 
1073 	return 0;
1074 }
1075 
1076 #ifdef CONFIG_PAGE_POOL
1077 
1078 /* This is the number of tokens and frags that the user can SO_DEVMEM_DONTNEED
1079  * in 1 syscall. The limit exists to limit the amount of memory the kernel
1080  * allocates to copy these tokens, and to prevent looping over the frags for
1081  * too long.
1082  */
1083 #define MAX_DONTNEED_TOKENS 128
1084 #define MAX_DONTNEED_FRAGS 1024
1085 
1086 static noinline_for_stack int
1087 sock_devmem_dontneed(struct sock *sk, sockptr_t optval, unsigned int optlen)
1088 {
1089 	unsigned int num_tokens, i, j, k, netmem_num = 0;
1090 	struct dmabuf_token *tokens;
1091 	int ret = 0, num_frags = 0;
1092 	netmem_ref netmems[16];
1093 
1094 	if (!sk_is_tcp(sk))
1095 		return -EBADF;
1096 
1097 	if (optlen % sizeof(*tokens) ||
1098 	    optlen > sizeof(*tokens) * MAX_DONTNEED_TOKENS)
1099 		return -EINVAL;
1100 
1101 	num_tokens = optlen / sizeof(*tokens);
1102 	tokens = kvmalloc_objs(*tokens, num_tokens);
1103 	if (!tokens)
1104 		return -ENOMEM;
1105 
1106 	if (copy_from_sockptr(tokens, optval, optlen)) {
1107 		kvfree(tokens);
1108 		return -EFAULT;
1109 	}
1110 
1111 	xa_lock_bh(&sk->sk_user_frags);
1112 	for (i = 0; i < num_tokens; i++) {
1113 		for (j = 0; j < tokens[i].token_count; j++) {
1114 			if (++num_frags > MAX_DONTNEED_FRAGS)
1115 				goto frag_limit_reached;
1116 
1117 			netmem_ref netmem = (__force netmem_ref)__xa_erase(
1118 				&sk->sk_user_frags, tokens[i].token_start + j);
1119 
1120 			if (!netmem || WARN_ON_ONCE(!netmem_is_net_iov(netmem)))
1121 				continue;
1122 
1123 			netmems[netmem_num++] = netmem;
1124 			if (netmem_num == ARRAY_SIZE(netmems)) {
1125 				xa_unlock_bh(&sk->sk_user_frags);
1126 				for (k = 0; k < netmem_num; k++)
1127 					WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1128 				netmem_num = 0;
1129 				xa_lock_bh(&sk->sk_user_frags);
1130 			}
1131 			ret++;
1132 		}
1133 	}
1134 
1135 frag_limit_reached:
1136 	xa_unlock_bh(&sk->sk_user_frags);
1137 	for (k = 0; k < netmem_num; k++)
1138 		WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1139 
1140 	kvfree(tokens);
1141 	return ret;
1142 }
1143 #endif
1144 
1145 void sockopt_lock_sock(struct sock *sk)
1146 {
1147 	/* When current->bpf_ctx is set, the setsockopt is called from
1148 	 * a bpf prog.  bpf has ensured the sk lock has been
1149 	 * acquired before calling setsockopt().
1150 	 */
1151 	if (has_current_bpf_ctx())
1152 		return;
1153 
1154 	lock_sock(sk);
1155 }
1156 EXPORT_SYMBOL(sockopt_lock_sock);
1157 
1158 void sockopt_release_sock(struct sock *sk)
1159 {
1160 	if (has_current_bpf_ctx())
1161 		return;
1162 
1163 	release_sock(sk);
1164 }
1165 EXPORT_SYMBOL(sockopt_release_sock);
1166 
1167 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1168 {
1169 	return has_current_bpf_ctx() || ns_capable(ns, cap);
1170 }
1171 EXPORT_SYMBOL(sockopt_ns_capable);
1172 
1173 bool sockopt_capable(int cap)
1174 {
1175 	return has_current_bpf_ctx() || capable(cap);
1176 }
1177 EXPORT_SYMBOL(sockopt_capable);
1178 
1179 static int sockopt_validate_clockid(__kernel_clockid_t value)
1180 {
1181 	switch (value) {
1182 	case CLOCK_REALTIME:
1183 	case CLOCK_MONOTONIC:
1184 	case CLOCK_TAI:
1185 		return 0;
1186 	}
1187 	return -EINVAL;
1188 }
1189 
1190 /*
1191  *	This is meant for all protocols to use and covers goings on
1192  *	at the socket level. Everything here is generic.
1193  */
1194 
1195 int sk_setsockopt(struct sock *sk, int level, int optname,
1196 		  sockptr_t optval, unsigned int optlen)
1197 {
1198 	struct so_timestamping timestamping;
1199 	struct socket *sock = sk->sk_socket;
1200 	struct sock_txtime sk_txtime;
1201 	int val;
1202 	int valbool;
1203 	struct linger ling;
1204 	int ret = 0;
1205 
1206 	/*
1207 	 *	Options without arguments
1208 	 */
1209 
1210 	if (optname == SO_BINDTODEVICE)
1211 		return sock_setbindtodevice(sk, optval, optlen);
1212 
1213 	if (optlen < sizeof(int))
1214 		return -EINVAL;
1215 
1216 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1217 		return -EFAULT;
1218 
1219 	valbool = val ? 1 : 0;
1220 
1221 	/* handle options which do not require locking the socket. */
1222 	switch (optname) {
1223 	case SO_PRIORITY:
1224 		if (sk_set_prio_allowed(sk, val)) {
1225 			sock_set_priority(sk, val);
1226 			return 0;
1227 		}
1228 		return -EPERM;
1229 	case SO_TYPE:
1230 	case SO_PROTOCOL:
1231 	case SO_DOMAIN:
1232 	case SO_ERROR:
1233 		return -ENOPROTOOPT;
1234 #ifdef CONFIG_NET_RX_BUSY_POLL
1235 	case SO_BUSY_POLL:
1236 		if (val < 0)
1237 			return -EINVAL;
1238 		WRITE_ONCE(sk->sk_ll_usec, val);
1239 		return 0;
1240 	case SO_PREFER_BUSY_POLL:
1241 		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1242 			return -EPERM;
1243 		WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1244 		return 0;
1245 	case SO_BUSY_POLL_BUDGET:
1246 		if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1247 		    !sockopt_capable(CAP_NET_ADMIN))
1248 			return -EPERM;
1249 		if (val < 0 || val > U16_MAX)
1250 			return -EINVAL;
1251 		WRITE_ONCE(sk->sk_busy_poll_budget, val);
1252 		return 0;
1253 #endif
1254 	case SO_MAX_PACING_RATE:
1255 		{
1256 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1257 		unsigned long pacing_rate;
1258 
1259 		if (sizeof(ulval) != sizeof(val) &&
1260 		    optlen >= sizeof(ulval) &&
1261 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1262 			return -EFAULT;
1263 		}
1264 		if (ulval != ~0UL)
1265 			cmpxchg(&sk->sk_pacing_status,
1266 				SK_PACING_NONE,
1267 				SK_PACING_NEEDED);
1268 		/* Pairs with READ_ONCE() from sk_getsockopt() */
1269 		WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1270 		pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1271 		if (ulval < pacing_rate)
1272 			WRITE_ONCE(sk->sk_pacing_rate, ulval);
1273 		return 0;
1274 		}
1275 	case SO_TXREHASH:
1276 		if (!sk_is_tcp(sk))
1277 			return -EOPNOTSUPP;
1278 		if (val < -1 || val > 1)
1279 			return -EINVAL;
1280 		if ((u8)val == SOCK_TXREHASH_DEFAULT)
1281 			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1282 		/* Paired with READ_ONCE() in tcp_rtx_synack()
1283 		 * and sk_getsockopt().
1284 		 */
1285 		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1286 		return 0;
1287 	case SO_PEEK_OFF:
1288 		{
1289 		int (*set_peek_off)(struct sock *sk, int val);
1290 
1291 		set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1292 		if (set_peek_off)
1293 			ret = set_peek_off(sk, val);
1294 		else
1295 			ret = -EOPNOTSUPP;
1296 		return ret;
1297 		}
1298 #ifdef CONFIG_PAGE_POOL
1299 	case SO_DEVMEM_DONTNEED:
1300 		return sock_devmem_dontneed(sk, optval, optlen);
1301 #endif
1302 	case SO_SNDTIMEO_OLD:
1303 	case SO_SNDTIMEO_NEW:
1304 		return sock_set_timeout(&sk->sk_sndtimeo, optval,
1305 					optlen, optname == SO_SNDTIMEO_OLD);
1306 	case SO_RCVTIMEO_OLD:
1307 	case SO_RCVTIMEO_NEW:
1308 		return sock_set_timeout(&sk->sk_rcvtimeo, optval,
1309 					optlen, optname == SO_RCVTIMEO_OLD);
1310 	}
1311 
1312 	sockopt_lock_sock(sk);
1313 
1314 	switch (optname) {
1315 	case SO_DEBUG:
1316 		if (val && !sockopt_capable(CAP_NET_ADMIN))
1317 			ret = -EACCES;
1318 		else
1319 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1320 		break;
1321 	case SO_REUSEADDR:
1322 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1323 		break;
1324 	case SO_REUSEPORT:
1325 		if (valbool && !sk_is_inet(sk))
1326 			ret = -EOPNOTSUPP;
1327 		else
1328 			sk->sk_reuseport = valbool;
1329 		break;
1330 	case SO_DONTROUTE:
1331 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1332 		sk_dst_reset(sk);
1333 		break;
1334 	case SO_BROADCAST:
1335 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1336 		break;
1337 	case SO_SNDBUF:
1338 		/* Don't error on this BSD doesn't and if you think
1339 		 * about it this is right. Otherwise apps have to
1340 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1341 		 * are treated in BSD as hints
1342 		 */
1343 		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1344 set_sndbuf:
1345 		/* Ensure val * 2 fits into an int, to prevent max_t()
1346 		 * from treating it as a negative value.
1347 		 */
1348 		val = min_t(int, val, INT_MAX / 2);
1349 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1350 		WRITE_ONCE(sk->sk_sndbuf,
1351 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1352 		/* Wake up sending tasks if we upped the value. */
1353 		sk->sk_write_space(sk);
1354 		break;
1355 
1356 	case SO_SNDBUFFORCE:
1357 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1358 			ret = -EPERM;
1359 			break;
1360 		}
1361 
1362 		/* No negative values (to prevent underflow, as val will be
1363 		 * multiplied by 2).
1364 		 */
1365 		if (val < 0)
1366 			val = 0;
1367 		goto set_sndbuf;
1368 
1369 	case SO_RCVBUF:
1370 		/* Don't error on this BSD doesn't and if you think
1371 		 * about it this is right. Otherwise apps have to
1372 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1373 		 * are treated in BSD as hints
1374 		 */
1375 		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1376 		break;
1377 
1378 	case SO_RCVBUFFORCE:
1379 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1380 			ret = -EPERM;
1381 			break;
1382 		}
1383 
1384 		/* No negative values (to prevent underflow, as val will be
1385 		 * multiplied by 2).
1386 		 */
1387 		__sock_set_rcvbuf(sk, max(val, 0));
1388 		break;
1389 
1390 	case SO_KEEPALIVE:
1391 		if (sk->sk_prot->keepalive)
1392 			sk->sk_prot->keepalive(sk, valbool);
1393 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1394 		break;
1395 
1396 	case SO_OOBINLINE:
1397 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1398 		break;
1399 
1400 	case SO_NO_CHECK:
1401 		sk->sk_no_check_tx = valbool;
1402 		break;
1403 
1404 	case SO_LINGER:
1405 		if (optlen < sizeof(ling)) {
1406 			ret = -EINVAL;	/* 1003.1g */
1407 			break;
1408 		}
1409 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1410 			ret = -EFAULT;
1411 			break;
1412 		}
1413 		if (!ling.l_onoff) {
1414 			sock_reset_flag(sk, SOCK_LINGER);
1415 		} else {
1416 			unsigned long t_sec = ling.l_linger;
1417 
1418 			if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1419 				WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1420 			else
1421 				WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
1422 			sock_set_flag(sk, SOCK_LINGER);
1423 		}
1424 		break;
1425 
1426 	case SO_BSDCOMPAT:
1427 		break;
1428 
1429 	case SO_TIMESTAMP_OLD:
1430 	case SO_TIMESTAMP_NEW:
1431 	case SO_TIMESTAMPNS_OLD:
1432 	case SO_TIMESTAMPNS_NEW:
1433 		sock_set_timestamp(sk, optname, valbool);
1434 		break;
1435 
1436 	case SO_TIMESTAMPING_NEW:
1437 	case SO_TIMESTAMPING_OLD:
1438 		if (optlen == sizeof(timestamping)) {
1439 			if (copy_from_sockptr(&timestamping, optval,
1440 					      sizeof(timestamping))) {
1441 				ret = -EFAULT;
1442 				break;
1443 			}
1444 		} else {
1445 			memset(&timestamping, 0, sizeof(timestamping));
1446 			timestamping.flags = val;
1447 		}
1448 		ret = sock_set_timestamping(sk, optname, timestamping);
1449 		break;
1450 
1451 	case SO_RCVLOWAT:
1452 		{
1453 		int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
1454 
1455 		if (val < 0)
1456 			val = INT_MAX;
1457 		if (sock)
1458 			set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1459 		if (set_rcvlowat)
1460 			ret = set_rcvlowat(sk, val);
1461 		else
1462 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1463 		break;
1464 		}
1465 	case SO_ATTACH_FILTER: {
1466 		struct sock_fprog fprog;
1467 
1468 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1469 		if (!ret)
1470 			ret = sk_attach_filter(&fprog, sk);
1471 		break;
1472 	}
1473 	case SO_ATTACH_BPF:
1474 		ret = -EINVAL;
1475 		if (optlen == sizeof(u32)) {
1476 			u32 ufd;
1477 
1478 			ret = -EFAULT;
1479 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1480 				break;
1481 
1482 			ret = sk_attach_bpf(ufd, sk);
1483 		}
1484 		break;
1485 
1486 	case SO_ATTACH_REUSEPORT_CBPF: {
1487 		struct sock_fprog fprog;
1488 
1489 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1490 		if (!ret)
1491 			ret = sk_reuseport_attach_filter(&fprog, sk);
1492 		break;
1493 	}
1494 	case SO_ATTACH_REUSEPORT_EBPF:
1495 		ret = -EINVAL;
1496 		if (optlen == sizeof(u32)) {
1497 			u32 ufd;
1498 
1499 			ret = -EFAULT;
1500 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1501 				break;
1502 
1503 			ret = sk_reuseport_attach_bpf(ufd, sk);
1504 		}
1505 		break;
1506 
1507 	case SO_DETACH_REUSEPORT_BPF:
1508 		ret = reuseport_detach_prog(sk);
1509 		break;
1510 
1511 	case SO_DETACH_FILTER:
1512 		ret = sk_detach_filter(sk);
1513 		break;
1514 
1515 	case SO_LOCK_FILTER:
1516 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1517 			ret = -EPERM;
1518 		else
1519 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1520 		break;
1521 
1522 	case SO_MARK:
1523 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1524 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1525 			ret = -EPERM;
1526 			break;
1527 		}
1528 
1529 		__sock_set_mark(sk, val);
1530 		break;
1531 	case SO_RCVMARK:
1532 		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1533 		break;
1534 
1535 	case SO_RCVPRIORITY:
1536 		sock_valbool_flag(sk, SOCK_RCVPRIORITY, valbool);
1537 		break;
1538 
1539 	case SO_RXQ_OVFL:
1540 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1541 		break;
1542 
1543 	case SO_WIFI_STATUS:
1544 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1545 		break;
1546 
1547 	case SO_NOFCS:
1548 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1549 		break;
1550 
1551 	case SO_SELECT_ERR_QUEUE:
1552 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1553 		break;
1554 
1555 	case SO_PASSCRED:
1556 		if (sk_may_scm_recv(sk))
1557 			sk->sk_scm_credentials = valbool;
1558 		else
1559 			ret = -EOPNOTSUPP;
1560 		break;
1561 
1562 	case SO_PASSSEC:
1563 		if (IS_ENABLED(CONFIG_SECURITY_NETWORK) && sk_may_scm_recv(sk))
1564 			sk->sk_scm_security = valbool;
1565 		else
1566 			ret = -EOPNOTSUPP;
1567 		break;
1568 
1569 	case SO_PASSPIDFD:
1570 		if (sk_is_unix(sk))
1571 			sk->sk_scm_pidfd = valbool;
1572 		else
1573 			ret = -EOPNOTSUPP;
1574 		break;
1575 
1576 	case SO_PASSRIGHTS:
1577 		if (sk_is_unix(sk))
1578 			sk->sk_scm_rights = valbool;
1579 		else
1580 			ret = -EOPNOTSUPP;
1581 		break;
1582 
1583 	case SO_INCOMING_CPU:
1584 		reuseport_update_incoming_cpu(sk, val);
1585 		break;
1586 
1587 	case SO_CNX_ADVICE:
1588 		if (val == 1)
1589 			dst_negative_advice(sk);
1590 		break;
1591 
1592 	case SO_ZEROCOPY:
1593 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1594 			if (!(sk_is_tcp(sk) ||
1595 			      (sk->sk_type == SOCK_DGRAM &&
1596 			       sk->sk_protocol == IPPROTO_UDP)))
1597 				ret = -EOPNOTSUPP;
1598 		} else if (sk->sk_family != PF_RDS) {
1599 			ret = -EOPNOTSUPP;
1600 		}
1601 		if (!ret) {
1602 			if (val < 0 || val > 1)
1603 				ret = -EINVAL;
1604 			else
1605 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1606 		}
1607 		break;
1608 
1609 	case SO_TXTIME:
1610 		if (optlen != sizeof(struct sock_txtime)) {
1611 			ret = -EINVAL;
1612 			break;
1613 		} else if (copy_from_sockptr(&sk_txtime, optval,
1614 			   sizeof(struct sock_txtime))) {
1615 			ret = -EFAULT;
1616 			break;
1617 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1618 			ret = -EINVAL;
1619 			break;
1620 		}
1621 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1622 		 * scheduler has enough safe guards.
1623 		 */
1624 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1625 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1626 			ret = -EPERM;
1627 			break;
1628 		}
1629 
1630 		ret = sockopt_validate_clockid(sk_txtime.clockid);
1631 		if (ret)
1632 			break;
1633 
1634 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1635 		sk->sk_clockid = sk_txtime.clockid;
1636 		sk->sk_txtime_deadline_mode =
1637 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1638 		sk->sk_txtime_report_errors =
1639 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1640 		break;
1641 
1642 	case SO_BINDTOIFINDEX:
1643 		ret = sock_bindtoindex_locked(sk, val);
1644 		break;
1645 
1646 	case SO_BUF_LOCK:
1647 		if (val & ~SOCK_BUF_LOCK_MASK) {
1648 			ret = -EINVAL;
1649 			break;
1650 		}
1651 		sk->sk_userlocks = val | (sk->sk_userlocks &
1652 					  ~SOCK_BUF_LOCK_MASK);
1653 		break;
1654 
1655 	case SO_RESERVE_MEM:
1656 	{
1657 		int delta;
1658 
1659 		if (val < 0) {
1660 			ret = -EINVAL;
1661 			break;
1662 		}
1663 
1664 		delta = val - sk->sk_reserved_mem;
1665 		if (delta < 0)
1666 			sock_release_reserved_memory(sk, -delta);
1667 		else
1668 			ret = sock_reserve_memory(sk, delta);
1669 		break;
1670 	}
1671 
1672 	default:
1673 		ret = -ENOPROTOOPT;
1674 		break;
1675 	}
1676 	sockopt_release_sock(sk);
1677 	return ret;
1678 }
1679 
1680 int sock_setsockopt(struct socket *sock, int level, int optname,
1681 		    sockptr_t optval, unsigned int optlen)
1682 {
1683 	return sk_setsockopt(sock->sk, level, optname,
1684 			     optval, optlen);
1685 }
1686 EXPORT_SYMBOL(sock_setsockopt);
1687 
1688 static const struct cred *sk_get_peer_cred(struct sock *sk)
1689 {
1690 	const struct cred *cred;
1691 
1692 	spin_lock(&sk->sk_peer_lock);
1693 	cred = get_cred(sk->sk_peer_cred);
1694 	spin_unlock(&sk->sk_peer_lock);
1695 
1696 	return cred;
1697 }
1698 
1699 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1700 			  struct ucred *ucred)
1701 {
1702 	ucred->pid = pid_vnr(pid);
1703 	ucred->uid = ucred->gid = -1;
1704 	if (cred) {
1705 		struct user_namespace *current_ns = current_user_ns();
1706 
1707 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1708 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1709 	}
1710 }
1711 
1712 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1713 {
1714 	struct user_namespace *user_ns = current_user_ns();
1715 	int i;
1716 
1717 	for (i = 0; i < src->ngroups; i++) {
1718 		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1719 
1720 		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1721 			return -EFAULT;
1722 	}
1723 
1724 	return 0;
1725 }
1726 
1727 int sk_getsockopt(struct sock *sk, int level, int optname,
1728 		  sockptr_t optval, sockptr_t optlen)
1729 {
1730 	struct socket *sock = sk->sk_socket;
1731 
1732 	union {
1733 		int val;
1734 		u64 val64;
1735 		unsigned long ulval;
1736 		struct linger ling;
1737 		struct old_timeval32 tm32;
1738 		struct __kernel_old_timeval tm;
1739 		struct  __kernel_sock_timeval stm;
1740 		struct sock_txtime txtime;
1741 		struct so_timestamping timestamping;
1742 	} v;
1743 
1744 	int lv = sizeof(int);
1745 	int len;
1746 
1747 	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1748 		return -EFAULT;
1749 	if (len < 0)
1750 		return -EINVAL;
1751 
1752 	memset(&v, 0, sizeof(v));
1753 
1754 	switch (optname) {
1755 	case SO_DEBUG:
1756 		v.val = sock_flag(sk, SOCK_DBG);
1757 		break;
1758 
1759 	case SO_DONTROUTE:
1760 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1761 		break;
1762 
1763 	case SO_BROADCAST:
1764 		v.val = sock_flag(sk, SOCK_BROADCAST);
1765 		break;
1766 
1767 	case SO_SNDBUF:
1768 		v.val = READ_ONCE(sk->sk_sndbuf);
1769 		break;
1770 
1771 	case SO_RCVBUF:
1772 		v.val = READ_ONCE(sk->sk_rcvbuf);
1773 		break;
1774 
1775 	case SO_REUSEADDR:
1776 		v.val = sk->sk_reuse;
1777 		break;
1778 
1779 	case SO_REUSEPORT:
1780 		v.val = sk->sk_reuseport;
1781 		break;
1782 
1783 	case SO_KEEPALIVE:
1784 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1785 		break;
1786 
1787 	case SO_TYPE:
1788 		v.val = sk->sk_type;
1789 		break;
1790 
1791 	case SO_PROTOCOL:
1792 		v.val = sk->sk_protocol;
1793 		break;
1794 
1795 	case SO_DOMAIN:
1796 		v.val = sk->sk_family;
1797 		break;
1798 
1799 	case SO_ERROR:
1800 		v.val = -sock_error(sk);
1801 		if (v.val == 0)
1802 			v.val = xchg(&sk->sk_err_soft, 0);
1803 		break;
1804 
1805 	case SO_OOBINLINE:
1806 		v.val = sock_flag(sk, SOCK_URGINLINE);
1807 		break;
1808 
1809 	case SO_NO_CHECK:
1810 		v.val = sk->sk_no_check_tx;
1811 		break;
1812 
1813 	case SO_PRIORITY:
1814 		v.val = READ_ONCE(sk->sk_priority);
1815 		break;
1816 
1817 	case SO_LINGER:
1818 		lv		= sizeof(v.ling);
1819 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1820 		v.ling.l_linger	= READ_ONCE(sk->sk_lingertime) / HZ;
1821 		break;
1822 
1823 	case SO_BSDCOMPAT:
1824 		break;
1825 
1826 	case SO_TIMESTAMP_OLD:
1827 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1828 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1829 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1830 		break;
1831 
1832 	case SO_TIMESTAMPNS_OLD:
1833 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1834 		break;
1835 
1836 	case SO_TIMESTAMP_NEW:
1837 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1838 		break;
1839 
1840 	case SO_TIMESTAMPNS_NEW:
1841 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1842 		break;
1843 
1844 	case SO_TIMESTAMPING_OLD:
1845 	case SO_TIMESTAMPING_NEW:
1846 		lv = sizeof(v.timestamping);
1847 		/* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1848 		 * returning the flags when they were set through the same option.
1849 		 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1850 		 */
1851 		if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1852 			v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1853 			v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1854 		}
1855 		break;
1856 
1857 	case SO_RCVTIMEO_OLD:
1858 	case SO_RCVTIMEO_NEW:
1859 		lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1860 				      SO_RCVTIMEO_OLD == optname);
1861 		break;
1862 
1863 	case SO_SNDTIMEO_OLD:
1864 	case SO_SNDTIMEO_NEW:
1865 		lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1866 				      SO_SNDTIMEO_OLD == optname);
1867 		break;
1868 
1869 	case SO_RCVLOWAT:
1870 		v.val = READ_ONCE(sk->sk_rcvlowat);
1871 		break;
1872 
1873 	case SO_SNDLOWAT:
1874 		v.val = 1;
1875 		break;
1876 
1877 	case SO_PASSCRED:
1878 		if (!sk_may_scm_recv(sk))
1879 			return -EOPNOTSUPP;
1880 
1881 		v.val = sk->sk_scm_credentials;
1882 		break;
1883 
1884 	case SO_PASSPIDFD:
1885 		if (!sk_is_unix(sk))
1886 			return -EOPNOTSUPP;
1887 
1888 		v.val = sk->sk_scm_pidfd;
1889 		break;
1890 
1891 	case SO_PASSRIGHTS:
1892 		if (!sk_is_unix(sk))
1893 			return -EOPNOTSUPP;
1894 
1895 		v.val = sk->sk_scm_rights;
1896 		break;
1897 
1898 	case SO_PEERCRED:
1899 	{
1900 		struct ucred peercred;
1901 		if (len > sizeof(peercred))
1902 			len = sizeof(peercred);
1903 
1904 		spin_lock(&sk->sk_peer_lock);
1905 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1906 		spin_unlock(&sk->sk_peer_lock);
1907 
1908 		if (copy_to_sockptr(optval, &peercred, len))
1909 			return -EFAULT;
1910 		goto lenout;
1911 	}
1912 
1913 	case SO_PEERPIDFD:
1914 	{
1915 		struct pid *peer_pid;
1916 		struct file *pidfd_file = NULL;
1917 		unsigned int flags = 0;
1918 		int pidfd;
1919 
1920 		if (len > sizeof(pidfd))
1921 			len = sizeof(pidfd);
1922 
1923 		spin_lock(&sk->sk_peer_lock);
1924 		peer_pid = get_pid(sk->sk_peer_pid);
1925 		spin_unlock(&sk->sk_peer_lock);
1926 
1927 		if (!peer_pid)
1928 			return -ENODATA;
1929 
1930 		/* The use of PIDFD_STALE requires stashing of struct pid
1931 		 * on pidfs with pidfs_register_pid() and only AF_UNIX
1932 		 * were prepared for this.
1933 		 */
1934 		if (sk->sk_family == AF_UNIX)
1935 			flags = PIDFD_STALE;
1936 
1937 		pidfd = pidfd_prepare(peer_pid, flags, &pidfd_file);
1938 		put_pid(peer_pid);
1939 		if (pidfd < 0)
1940 			return pidfd;
1941 
1942 		if (copy_to_sockptr(optval, &pidfd, len) ||
1943 		    copy_to_sockptr(optlen, &len, sizeof(int))) {
1944 			put_unused_fd(pidfd);
1945 			fput(pidfd_file);
1946 
1947 			return -EFAULT;
1948 		}
1949 
1950 		fd_install(pidfd, pidfd_file);
1951 		return 0;
1952 	}
1953 
1954 	case SO_PEERGROUPS:
1955 	{
1956 		const struct cred *cred;
1957 		int ret, n;
1958 
1959 		cred = sk_get_peer_cred(sk);
1960 		if (!cred)
1961 			return -ENODATA;
1962 
1963 		n = cred->group_info->ngroups;
1964 		if (len < n * sizeof(gid_t)) {
1965 			len = n * sizeof(gid_t);
1966 			put_cred(cred);
1967 			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1968 		}
1969 		len = n * sizeof(gid_t);
1970 
1971 		ret = groups_to_user(optval, cred->group_info);
1972 		put_cred(cred);
1973 		if (ret)
1974 			return ret;
1975 		goto lenout;
1976 	}
1977 
1978 	case SO_PEERNAME:
1979 	{
1980 		struct sockaddr_storage address;
1981 
1982 		lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1983 		if (lv < 0)
1984 			return -ENOTCONN;
1985 		if (lv < len)
1986 			return -EINVAL;
1987 		if (copy_to_sockptr(optval, &address, len))
1988 			return -EFAULT;
1989 		goto lenout;
1990 	}
1991 
1992 	/* Dubious BSD thing... Probably nobody even uses it, but
1993 	 * the UNIX standard wants it for whatever reason... -DaveM
1994 	 */
1995 	case SO_ACCEPTCONN:
1996 		v.val = sk->sk_state == TCP_LISTEN;
1997 		break;
1998 
1999 	case SO_PASSSEC:
2000 		if (!IS_ENABLED(CONFIG_SECURITY_NETWORK) || !sk_may_scm_recv(sk))
2001 			return -EOPNOTSUPP;
2002 
2003 		v.val = sk->sk_scm_security;
2004 		break;
2005 
2006 	case SO_PEERSEC:
2007 		return security_socket_getpeersec_stream(sock,
2008 							 optval, optlen, len);
2009 
2010 	case SO_MARK:
2011 		v.val = READ_ONCE(sk->sk_mark);
2012 		break;
2013 
2014 	case SO_RCVMARK:
2015 		v.val = sock_flag(sk, SOCK_RCVMARK);
2016 		break;
2017 
2018 	case SO_RCVPRIORITY:
2019 		v.val = sock_flag(sk, SOCK_RCVPRIORITY);
2020 		break;
2021 
2022 	case SO_RXQ_OVFL:
2023 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
2024 		break;
2025 
2026 	case SO_WIFI_STATUS:
2027 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
2028 		break;
2029 
2030 	case SO_PEEK_OFF:
2031 		if (!READ_ONCE(sock->ops)->set_peek_off)
2032 			return -EOPNOTSUPP;
2033 
2034 		v.val = READ_ONCE(sk->sk_peek_off);
2035 		break;
2036 	case SO_NOFCS:
2037 		v.val = sock_flag(sk, SOCK_NOFCS);
2038 		break;
2039 
2040 	case SO_BINDTODEVICE:
2041 		return sock_getbindtodevice(sk, optval, optlen, len);
2042 
2043 	case SO_GET_FILTER:
2044 		len = sk_get_filter(sk, optval, len);
2045 		if (len < 0)
2046 			return len;
2047 
2048 		goto lenout;
2049 
2050 	case SO_LOCK_FILTER:
2051 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
2052 		break;
2053 
2054 	case SO_BPF_EXTENSIONS:
2055 		v.val = bpf_tell_extensions();
2056 		break;
2057 
2058 	case SO_SELECT_ERR_QUEUE:
2059 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
2060 		break;
2061 
2062 #ifdef CONFIG_NET_RX_BUSY_POLL
2063 	case SO_BUSY_POLL:
2064 		v.val = READ_ONCE(sk->sk_ll_usec);
2065 		break;
2066 	case SO_PREFER_BUSY_POLL:
2067 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
2068 		break;
2069 #endif
2070 
2071 	case SO_MAX_PACING_RATE:
2072 		/* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
2073 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
2074 			lv = sizeof(v.ulval);
2075 			v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
2076 		} else {
2077 			/* 32bit version */
2078 			v.val = min_t(unsigned long, ~0U,
2079 				      READ_ONCE(sk->sk_max_pacing_rate));
2080 		}
2081 		break;
2082 
2083 	case SO_INCOMING_CPU:
2084 		v.val = READ_ONCE(sk->sk_incoming_cpu);
2085 		break;
2086 
2087 	case SO_MEMINFO:
2088 	{
2089 		u32 meminfo[SK_MEMINFO_VARS];
2090 
2091 		sk_get_meminfo(sk, meminfo);
2092 
2093 		len = min_t(unsigned int, len, sizeof(meminfo));
2094 		if (copy_to_sockptr(optval, &meminfo, len))
2095 			return -EFAULT;
2096 
2097 		goto lenout;
2098 	}
2099 
2100 #ifdef CONFIG_NET_RX_BUSY_POLL
2101 	case SO_INCOMING_NAPI_ID:
2102 		v.val = READ_ONCE(sk->sk_napi_id);
2103 
2104 		/* aggregate non-NAPI IDs down to 0 */
2105 		if (!napi_id_valid(v.val))
2106 			v.val = 0;
2107 
2108 		break;
2109 #endif
2110 
2111 	case SO_COOKIE:
2112 		lv = sizeof(u64);
2113 		if (len < lv)
2114 			return -EINVAL;
2115 		v.val64 = sock_gen_cookie(sk);
2116 		break;
2117 
2118 	case SO_ZEROCOPY:
2119 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
2120 		break;
2121 
2122 	case SO_TXTIME:
2123 		lv = sizeof(v.txtime);
2124 		v.txtime.clockid = sk->sk_clockid;
2125 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
2126 				  SOF_TXTIME_DEADLINE_MODE : 0;
2127 		v.txtime.flags |= sk->sk_txtime_report_errors ?
2128 				  SOF_TXTIME_REPORT_ERRORS : 0;
2129 		break;
2130 
2131 	case SO_BINDTOIFINDEX:
2132 		v.val = READ_ONCE(sk->sk_bound_dev_if);
2133 		break;
2134 
2135 	case SO_NETNS_COOKIE:
2136 		lv = sizeof(u64);
2137 		if (len != lv)
2138 			return -EINVAL;
2139 		v.val64 = sock_net(sk)->net_cookie;
2140 		break;
2141 
2142 	case SO_BUF_LOCK:
2143 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
2144 		break;
2145 
2146 	case SO_RESERVE_MEM:
2147 		v.val = READ_ONCE(sk->sk_reserved_mem);
2148 		break;
2149 
2150 	case SO_TXREHASH:
2151 		if (!sk_is_tcp(sk))
2152 			return -EOPNOTSUPP;
2153 
2154 		/* Paired with WRITE_ONCE() in sk_setsockopt() */
2155 		v.val = READ_ONCE(sk->sk_txrehash);
2156 		break;
2157 
2158 	default:
2159 		/* We implement the SO_SNDLOWAT etc to not be settable
2160 		 * (1003.1g 7).
2161 		 */
2162 		return -ENOPROTOOPT;
2163 	}
2164 
2165 	if (len > lv)
2166 		len = lv;
2167 	if (copy_to_sockptr(optval, &v, len))
2168 		return -EFAULT;
2169 lenout:
2170 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
2171 		return -EFAULT;
2172 	return 0;
2173 }
2174 
2175 /*
2176  * Initialize an sk_lock.
2177  *
2178  * (We also register the sk_lock with the lock validator.)
2179  */
2180 static inline void sock_lock_init(struct sock *sk)
2181 {
2182 	sk_owner_clear(sk);
2183 
2184 	if (sk->sk_kern_sock)
2185 		sock_lock_init_class_and_name(
2186 			sk,
2187 			af_family_kern_slock_key_strings[sk->sk_family],
2188 			af_family_kern_slock_keys + sk->sk_family,
2189 			af_family_kern_key_strings[sk->sk_family],
2190 			af_family_kern_keys + sk->sk_family);
2191 	else
2192 		sock_lock_init_class_and_name(
2193 			sk,
2194 			af_family_slock_key_strings[sk->sk_family],
2195 			af_family_slock_keys + sk->sk_family,
2196 			af_family_key_strings[sk->sk_family],
2197 			af_family_keys + sk->sk_family);
2198 }
2199 
2200 /*
2201  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2202  * even temporarily, because of RCU lookups. sk_node should also be left as is.
2203  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2204  */
2205 static void sock_copy(struct sock *nsk, const struct sock *osk)
2206 {
2207 	const struct proto *prot = READ_ONCE(osk->sk_prot);
2208 #ifdef CONFIG_SECURITY_NETWORK
2209 	void *sptr = nsk->sk_security;
2210 #endif
2211 
2212 	/* If we move sk_tx_queue_mapping out of the private section,
2213 	 * we must check if sk_tx_queue_clear() is called after
2214 	 * sock_copy() in sk_clone_lock().
2215 	 */
2216 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2217 		     offsetof(struct sock, sk_dontcopy_begin) ||
2218 		     offsetof(struct sock, sk_tx_queue_mapping) >=
2219 		     offsetof(struct sock, sk_dontcopy_end));
2220 
2221 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2222 
2223 	unsafe_memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2224 		      prot->obj_size - offsetof(struct sock, sk_dontcopy_end),
2225 		      /* alloc is larger than struct, see sk_prot_alloc() */);
2226 
2227 #ifdef CONFIG_SECURITY_NETWORK
2228 	nsk->sk_security = sptr;
2229 	security_sk_clone(osk, nsk);
2230 #endif
2231 }
2232 
2233 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2234 		int family)
2235 {
2236 	struct sock *sk;
2237 	struct kmem_cache *slab;
2238 
2239 	slab = prot->slab;
2240 	if (slab != NULL) {
2241 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2242 		if (!sk)
2243 			return sk;
2244 		if (want_init_on_alloc(priority))
2245 			sk_prot_clear_nulls(sk, prot->obj_size);
2246 	} else
2247 		sk = kmalloc(prot->obj_size, priority);
2248 
2249 	if (sk != NULL) {
2250 		if (security_sk_alloc(sk, family, priority))
2251 			goto out_free;
2252 
2253 		if (!try_module_get(prot->owner))
2254 			goto out_free_sec;
2255 	}
2256 
2257 	return sk;
2258 
2259 out_free_sec:
2260 	security_sk_free(sk);
2261 out_free:
2262 	if (slab != NULL)
2263 		kmem_cache_free(slab, sk);
2264 	else
2265 		kfree(sk);
2266 	return NULL;
2267 }
2268 
2269 static void sk_prot_free(struct proto *prot, struct sock *sk)
2270 {
2271 	struct kmem_cache *slab;
2272 	struct module *owner;
2273 
2274 	owner = prot->owner;
2275 	slab = prot->slab;
2276 
2277 	cgroup_sk_free(&sk->sk_cgrp_data);
2278 	mem_cgroup_sk_free(sk);
2279 	security_sk_free(sk);
2280 
2281 	sk_owner_put(sk);
2282 
2283 	if (slab != NULL)
2284 		kmem_cache_free(slab, sk);
2285 	else
2286 		kfree(sk);
2287 	module_put(owner);
2288 }
2289 
2290 /**
2291  *	sk_alloc - All socket objects are allocated here
2292  *	@net: the applicable net namespace
2293  *	@family: protocol family
2294  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2295  *	@prot: struct proto associated with this new sock instance
2296  *	@kern: is this to be a kernel socket?
2297  */
2298 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2299 		      struct proto *prot, int kern)
2300 {
2301 	struct sock *sk;
2302 
2303 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2304 	if (sk) {
2305 		sk->sk_family = family;
2306 		/*
2307 		 * See comment in struct sock definition to understand
2308 		 * why we need sk_prot_creator -acme
2309 		 */
2310 		sk->sk_prot = sk->sk_prot_creator = prot;
2311 
2312 		if (READ_ONCE(net->core.sysctl_bypass_prot_mem))
2313 			sk->sk_bypass_prot_mem = 1;
2314 
2315 		sk->sk_kern_sock = kern;
2316 		sock_lock_init(sk);
2317 
2318 		sk->sk_net_refcnt = kern ? 0 : 1;
2319 		if (likely(sk->sk_net_refcnt)) {
2320 			get_net_track(net, &sk->ns_tracker, priority);
2321 			sock_inuse_add(net, 1);
2322 		} else {
2323 			net_passive_inc(net);
2324 			__netns_tracker_alloc(net, &sk->ns_tracker,
2325 					      false, priority);
2326 		}
2327 
2328 		sock_net_set(sk, net);
2329 		refcount_set(&sk->sk_wmem_alloc, SK_WMEM_ALLOC_BIAS);
2330 
2331 		mem_cgroup_sk_alloc(sk);
2332 		cgroup_sk_alloc(&sk->sk_cgrp_data);
2333 		sock_update_classid(&sk->sk_cgrp_data);
2334 		sock_update_netprioidx(&sk->sk_cgrp_data);
2335 		sk_tx_queue_clear(sk);
2336 	}
2337 
2338 	return sk;
2339 }
2340 EXPORT_SYMBOL(sk_alloc);
2341 
2342 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2343  * grace period. This is the case for UDP sockets and TCP listeners.
2344  */
2345 static void __sk_destruct(struct rcu_head *head)
2346 {
2347 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2348 	struct net *net = sock_net(sk);
2349 	struct sk_filter *filter;
2350 
2351 	if (sk->sk_destruct)
2352 		sk->sk_destruct(sk);
2353 
2354 	filter = rcu_dereference_check(sk->sk_filter,
2355 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2356 	if (filter) {
2357 		sk_filter_uncharge(sk, filter);
2358 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2359 	}
2360 
2361 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2362 
2363 #ifdef CONFIG_BPF_SYSCALL
2364 	bpf_sk_storage_free(sk);
2365 #endif
2366 
2367 	if (atomic_read(&sk->sk_omem_alloc))
2368 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2369 			 __func__, atomic_read(&sk->sk_omem_alloc));
2370 
2371 	if (sk->sk_frag.page) {
2372 		put_page(sk->sk_frag.page);
2373 		sk->sk_frag.page = NULL;
2374 	}
2375 
2376 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2377 	put_cred(sk->sk_peer_cred);
2378 	put_pid(sk->sk_peer_pid);
2379 
2380 	if (likely(sk->sk_net_refcnt)) {
2381 		put_net_track(net, &sk->ns_tracker);
2382 	} else {
2383 		__netns_tracker_free(net, &sk->ns_tracker, false);
2384 		net_passive_dec(net);
2385 	}
2386 	sk_prot_free(sk->sk_prot_creator, sk);
2387 }
2388 
2389 void sk_net_refcnt_upgrade(struct sock *sk)
2390 {
2391 	struct net *net = sock_net(sk);
2392 
2393 	WARN_ON_ONCE(sk->sk_net_refcnt);
2394 	__netns_tracker_free(net, &sk->ns_tracker, false);
2395 	net_passive_dec(net);
2396 	sk->sk_net_refcnt = 1;
2397 	get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
2398 	sock_inuse_add(net, 1);
2399 }
2400 EXPORT_SYMBOL_GPL(sk_net_refcnt_upgrade);
2401 
2402 void sk_destruct(struct sock *sk)
2403 {
2404 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2405 
2406 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2407 		reuseport_detach_sock(sk);
2408 		use_call_rcu = true;
2409 	}
2410 
2411 	if (use_call_rcu)
2412 		call_rcu(&sk->sk_rcu, __sk_destruct);
2413 	else
2414 		__sk_destruct(&sk->sk_rcu);
2415 }
2416 
2417 static void __sk_free(struct sock *sk)
2418 {
2419 	if (likely(sk->sk_net_refcnt))
2420 		sock_inuse_add(sock_net(sk), -1);
2421 
2422 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2423 		sock_diag_broadcast_destroy(sk);
2424 	else
2425 		sk_destruct(sk);
2426 }
2427 
2428 void sk_free(struct sock *sk)
2429 {
2430 	/*
2431 	 * We subtract one from sk_wmem_alloc and can know if
2432 	 * some packets are still in some tx queue.
2433 	 * If not null, sock_wfree() will call __sk_free(sk) later
2434 	 */
2435 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2436 		__sk_free(sk);
2437 }
2438 EXPORT_SYMBOL(sk_free);
2439 
2440 static void sk_init_common(struct sock *sk)
2441 {
2442 	skb_queue_head_init(&sk->sk_receive_queue);
2443 	skb_queue_head_init(&sk->sk_write_queue);
2444 	skb_queue_head_init(&sk->sk_error_queue);
2445 
2446 	rwlock_init(&sk->sk_callback_lock);
2447 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2448 			af_rlock_keys + sk->sk_family,
2449 			af_family_rlock_key_strings[sk->sk_family]);
2450 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2451 			af_wlock_keys + sk->sk_family,
2452 			af_family_wlock_key_strings[sk->sk_family]);
2453 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2454 			af_elock_keys + sk->sk_family,
2455 			af_family_elock_key_strings[sk->sk_family]);
2456 	if (sk->sk_kern_sock)
2457 		lockdep_set_class_and_name(&sk->sk_callback_lock,
2458 			af_kern_callback_keys + sk->sk_family,
2459 			af_family_kern_clock_key_strings[sk->sk_family]);
2460 	else
2461 		lockdep_set_class_and_name(&sk->sk_callback_lock,
2462 			af_callback_keys + sk->sk_family,
2463 			af_family_clock_key_strings[sk->sk_family]);
2464 }
2465 
2466 /**
2467  * sk_clone - clone a socket
2468  * @sk: the socket to clone
2469  * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2470  * @lock: if true, lock the cloned sk
2471  *
2472  * If @lock is true, the clone is locked by bh_lock_sock(), and
2473  * caller must unlock socket even in error path by bh_unlock_sock().
2474  */
2475 struct sock *sk_clone(const struct sock *sk, const gfp_t priority,
2476 		      bool lock)
2477 {
2478 	struct proto *prot = READ_ONCE(sk->sk_prot);
2479 	struct sk_filter *filter;
2480 	bool is_charged = true;
2481 	struct sock *newsk;
2482 
2483 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2484 	if (!newsk)
2485 		goto out;
2486 
2487 	sock_copy(newsk, sk);
2488 
2489 	newsk->sk_prot_creator = prot;
2490 
2491 	/* SANITY */
2492 	if (likely(newsk->sk_net_refcnt)) {
2493 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2494 		sock_inuse_add(sock_net(newsk), 1);
2495 	} else {
2496 		/* Kernel sockets are not elevating the struct net refcount.
2497 		 * Instead, use a tracker to more easily detect if a layer
2498 		 * is not properly dismantling its kernel sockets at netns
2499 		 * destroy time.
2500 		 */
2501 		net_passive_inc(sock_net(newsk));
2502 		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2503 				      false, priority);
2504 	}
2505 
2506 	sk_node_init(&newsk->sk_node);
2507 	sock_lock_init(newsk);
2508 
2509 	if (lock)
2510 		bh_lock_sock(newsk);
2511 
2512 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2513 	newsk->sk_backlog.len = 0;
2514 
2515 	atomic_set(&newsk->sk_rmem_alloc, 0);
2516 
2517 	refcount_set(&newsk->sk_wmem_alloc, SK_WMEM_ALLOC_BIAS);
2518 
2519 	atomic_set(&newsk->sk_omem_alloc, 0);
2520 	sk_init_common(newsk);
2521 
2522 	newsk->sk_dst_cache	= NULL;
2523 	newsk->sk_dst_pending_confirm = 0;
2524 	newsk->sk_wmem_queued	= 0;
2525 	newsk->sk_forward_alloc = 0;
2526 	newsk->sk_reserved_mem  = 0;
2527 	DEBUG_NET_WARN_ON_ONCE(newsk->sk_drop_counters);
2528 	sk_drops_reset(newsk);
2529 	newsk->sk_send_head	= NULL;
2530 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2531 	atomic_set(&newsk->sk_zckey, 0);
2532 
2533 	sock_reset_flag(newsk, SOCK_DONE);
2534 
2535 #ifdef CONFIG_MEMCG
2536 	/* sk->sk_memcg will be populated at accept() time */
2537 	newsk->sk_memcg = NULL;
2538 #endif
2539 
2540 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2541 
2542 	rcu_read_lock();
2543 	filter = rcu_dereference(sk->sk_filter);
2544 	if (filter != NULL)
2545 		/* though it's an empty new sock, the charging may fail
2546 		 * if sysctl_optmem_max was changed between creation of
2547 		 * original socket and cloning
2548 		 */
2549 		is_charged = sk_filter_charge(newsk, filter);
2550 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2551 	rcu_read_unlock();
2552 
2553 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2554 		/* We need to make sure that we don't uncharge the new
2555 		 * socket if we couldn't charge it in the first place
2556 		 * as otherwise we uncharge the parent's filter.
2557 		 */
2558 		if (!is_charged)
2559 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2560 
2561 		goto free;
2562 	}
2563 
2564 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2565 
2566 	if (bpf_sk_storage_clone(sk, newsk))
2567 		goto free;
2568 
2569 	/* Clear sk_user_data if parent had the pointer tagged
2570 	 * as not suitable for copying when cloning.
2571 	 */
2572 	if (sk_user_data_is_nocopy(newsk))
2573 		newsk->sk_user_data = NULL;
2574 
2575 	newsk->sk_err	   = 0;
2576 	newsk->sk_err_soft = 0;
2577 	newsk->sk_priority = 0;
2578 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2579 
2580 	/* Before updating sk_refcnt, we must commit prior changes to memory
2581 	 * (Documentation/RCU/rculist_nulls.rst for details)
2582 	 */
2583 	smp_wmb();
2584 	refcount_set(&newsk->sk_refcnt, 2);
2585 
2586 	sk_set_socket(newsk, NULL);
2587 	sk_tx_queue_clear(newsk);
2588 	sk_rx_queue_clear(newsk);
2589 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2590 
2591 	if (newsk->sk_prot->sockets_allocated)
2592 		sk_sockets_allocated_inc(newsk);
2593 
2594 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2595 		net_enable_timestamp();
2596 out:
2597 	return newsk;
2598 free:
2599 	/* It is still raw copy of parent, so invalidate
2600 	 * destructor and make plain sk_free()
2601 	 */
2602 	newsk->sk_destruct = NULL;
2603 	if (lock)
2604 		bh_unlock_sock(newsk);
2605 	sk_free(newsk);
2606 	newsk = NULL;
2607 	goto out;
2608 }
2609 EXPORT_SYMBOL_GPL(sk_clone);
2610 
2611 static u32 sk_dst_gso_max_size(struct sock *sk, const struct net_device *dev)
2612 {
2613 	bool is_ipv6 = false;
2614 	u32 max_size;
2615 
2616 #if IS_ENABLED(CONFIG_IPV6)
2617 	is_ipv6 = (sk->sk_family == AF_INET6 &&
2618 		   !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2619 #endif
2620 	/* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2621 	max_size = is_ipv6 ? READ_ONCE(dev->gso_max_size) :
2622 			READ_ONCE(dev->gso_ipv4_max_size);
2623 	if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2624 		max_size = GSO_LEGACY_MAX_SIZE;
2625 
2626 	return max_size - (MAX_TCP_HEADER + 1);
2627 }
2628 
2629 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2630 {
2631 	const struct net_device *dev;
2632 	u32 max_segs = 1;
2633 
2634 	rcu_read_lock();
2635 	dev = dst_dev_rcu(dst);
2636 	sk->sk_route_caps = dev->features;
2637 	if (sk_is_tcp(sk)) {
2638 		struct inet_connection_sock *icsk = inet_csk(sk);
2639 
2640 		sk->sk_route_caps |= NETIF_F_GSO;
2641 		icsk->icsk_ack.dst_quick_ack = dst_metric(dst, RTAX_QUICKACK);
2642 	}
2643 	if (sk->sk_route_caps & NETIF_F_GSO)
2644 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2645 	if (unlikely(sk->sk_gso_disabled))
2646 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2647 	if (sk_can_gso(sk)) {
2648 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2649 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2650 		} else {
2651 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2652 			sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dev);
2653 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2654 			max_segs = max_t(u32, READ_ONCE(dev->gso_max_segs), 1);
2655 		}
2656 	}
2657 	sk->sk_gso_max_segs = max_segs;
2658 	sk_dst_set(sk, dst);
2659 	rcu_read_unlock();
2660 }
2661 EXPORT_SYMBOL_GPL(sk_setup_caps);
2662 
2663 /*
2664  *	Simple resource managers for sockets.
2665  */
2666 
2667 
2668 /*
2669  * Write buffer destructor automatically called from kfree_skb.
2670  */
2671 void sock_wfree(struct sk_buff *skb)
2672 {
2673 	unsigned int len = skb->truesize;
2674 	struct sock *sk = skb->sk;
2675 	bool free;
2676 	int old;
2677 
2678 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2679 		if (sock_flag(sk, SOCK_RCU_FREE) &&
2680 		    sk->sk_write_space == sock_def_write_space) {
2681 			rcu_read_lock();
2682 			free = __refcount_sub_and_test(len, &sk->sk_wmem_alloc,
2683 						       &old);
2684 			sock_def_write_space_wfree(sk, old - len);
2685 			rcu_read_unlock();
2686 			if (unlikely(free))
2687 				__sk_free(sk);
2688 			return;
2689 		}
2690 
2691 		/*
2692 		 * Keep a reference on sk_wmem_alloc, this will be released
2693 		 * after sk_write_space() call
2694 		 */
2695 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2696 		sk->sk_write_space(sk);
2697 		len = 1;
2698 	}
2699 	/*
2700 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2701 	 * could not do because of in-flight packets
2702 	 */
2703 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2704 		__sk_free(sk);
2705 }
2706 EXPORT_SYMBOL(sock_wfree);
2707 
2708 /* This variant of sock_wfree() is used by TCP,
2709  * since it sets SOCK_USE_WRITE_QUEUE.
2710  */
2711 #ifdef CONFIG_INET
2712 void __sock_wfree(struct sk_buff *skb)
2713 {
2714 	struct sock *sk = skb->sk;
2715 
2716 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2717 		__sk_free(sk);
2718 }
2719 EXPORT_SYMBOL_GPL(__sock_wfree);
2720 #endif
2721 
2722 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2723 {
2724 	int old_wmem;
2725 
2726 	skb_orphan(skb);
2727 #ifdef CONFIG_INET
2728 	if (unlikely(!sk_fullsock(sk)))
2729 		return skb_set_owner_edemux(skb, sk);
2730 #endif
2731 	skb->sk = sk;
2732 	skb->destructor = sock_wfree;
2733 	skb_set_hash_from_sk(skb, sk);
2734 	/*
2735 	 * We used to take a refcount on sk, but following operation
2736 	 * is enough to guarantee sk_free() won't free this sock until
2737 	 * all in-flight packets are completed
2738 	 */
2739 	__refcount_add(skb->truesize, &sk->sk_wmem_alloc, &old_wmem);
2740 
2741 	/* (old_wmem == SK_WMEM_ALLOC_BIAS) if no other TX packet for this socket
2742 	 * is in a host queue (qdisc, NIC queue).
2743 	 * Set skb->ooo_okay so that netdev_pick_tx() can choose a TX queue
2744 	 * based on XPS for better performance.
2745 	 * Otherwise clear ooo_okay to not risk Out Of Order delivery.
2746 	 */
2747 	skb->ooo_okay = (old_wmem == SK_WMEM_ALLOC_BIAS);
2748 }
2749 EXPORT_SYMBOL(skb_set_owner_w);
2750 
2751 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2752 {
2753 	/* Drivers depend on in-order delivery for crypto offload,
2754 	 * partial orphan breaks out-of-order-OK logic.
2755 	 */
2756 	if (skb_is_decrypted(skb))
2757 		return false;
2758 
2759 	return (skb->destructor == sock_wfree ||
2760 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2761 }
2762 
2763 /* This helper is used by netem, as it can hold packets in its
2764  * delay queue. We want to allow the owner socket to send more
2765  * packets, as if they were already TX completed by a typical driver.
2766  * But we also want to keep skb->sk set because some packet schedulers
2767  * rely on it (sch_fq for example).
2768  */
2769 void skb_orphan_partial(struct sk_buff *skb)
2770 {
2771 	if (skb_is_tcp_pure_ack(skb))
2772 		return;
2773 
2774 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2775 		return;
2776 
2777 	skb_orphan(skb);
2778 }
2779 EXPORT_SYMBOL(skb_orphan_partial);
2780 
2781 /*
2782  * Read buffer destructor automatically called from kfree_skb.
2783  */
2784 void sock_rfree(struct sk_buff *skb)
2785 {
2786 	struct sock *sk = skb->sk;
2787 	unsigned int len = skb->truesize;
2788 
2789 	atomic_sub(len, &sk->sk_rmem_alloc);
2790 	sk_mem_uncharge(sk, len);
2791 }
2792 EXPORT_SYMBOL(sock_rfree);
2793 
2794 /*
2795  * Buffer destructor for skbs that are not used directly in read or write
2796  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2797  */
2798 void sock_efree(struct sk_buff *skb)
2799 {
2800 	sock_put(skb->sk);
2801 }
2802 EXPORT_SYMBOL(sock_efree);
2803 
2804 /* Buffer destructor for prefetch/receive path where reference count may
2805  * not be held, e.g. for listen sockets.
2806  */
2807 #ifdef CONFIG_INET
2808 void sock_pfree(struct sk_buff *skb)
2809 {
2810 	struct sock *sk = skb->sk;
2811 
2812 	if (!sk_is_refcounted(sk))
2813 		return;
2814 
2815 	if (sk->sk_state == TCP_NEW_SYN_RECV && inet_reqsk(sk)->syncookie) {
2816 		inet_reqsk(sk)->rsk_listener = NULL;
2817 		reqsk_free(inet_reqsk(sk));
2818 		return;
2819 	}
2820 
2821 	sock_gen_put(sk);
2822 }
2823 EXPORT_SYMBOL(sock_pfree);
2824 #endif /* CONFIG_INET */
2825 
2826 /*
2827  * Allocate a skb from the socket's send buffer.
2828  */
2829 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2830 			     gfp_t priority)
2831 {
2832 	if (force ||
2833 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2834 		struct sk_buff *skb = alloc_skb(size, priority);
2835 
2836 		if (skb) {
2837 			skb_set_owner_w(skb, sk);
2838 			return skb;
2839 		}
2840 	}
2841 	return NULL;
2842 }
2843 EXPORT_SYMBOL(sock_wmalloc);
2844 
2845 static void sock_ofree(struct sk_buff *skb)
2846 {
2847 	struct sock *sk = skb->sk;
2848 
2849 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2850 }
2851 
2852 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2853 			     gfp_t priority)
2854 {
2855 	struct sk_buff *skb;
2856 
2857 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2858 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2859 	    READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2860 		return NULL;
2861 
2862 	skb = alloc_skb(size, priority);
2863 	if (!skb)
2864 		return NULL;
2865 
2866 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2867 	skb->sk = sk;
2868 	skb->destructor = sock_ofree;
2869 	return skb;
2870 }
2871 
2872 /*
2873  * Allocate a memory block from the socket's option memory buffer.
2874  */
2875 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2876 {
2877 	int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2878 
2879 	if ((unsigned int)size <= optmem_max &&
2880 	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2881 		void *mem;
2882 		/* First do the add, to avoid the race if kmalloc
2883 		 * might sleep.
2884 		 */
2885 		atomic_add(size, &sk->sk_omem_alloc);
2886 		mem = kmalloc(size, priority);
2887 		if (mem)
2888 			return mem;
2889 		atomic_sub(size, &sk->sk_omem_alloc);
2890 	}
2891 	return NULL;
2892 }
2893 EXPORT_SYMBOL(sock_kmalloc);
2894 
2895 /*
2896  * Duplicate the input "src" memory block using the socket's
2897  * option memory buffer.
2898  */
2899 void *sock_kmemdup(struct sock *sk, const void *src,
2900 		   int size, gfp_t priority)
2901 {
2902 	void *mem;
2903 
2904 	mem = sock_kmalloc(sk, size, priority);
2905 	if (mem)
2906 		memcpy(mem, src, size);
2907 	return mem;
2908 }
2909 EXPORT_SYMBOL(sock_kmemdup);
2910 
2911 /* Free an option memory block. Note, we actually want the inline
2912  * here as this allows gcc to detect the nullify and fold away the
2913  * condition entirely.
2914  */
2915 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2916 				  const bool nullify)
2917 {
2918 	if (WARN_ON_ONCE(!mem))
2919 		return;
2920 	if (nullify)
2921 		kfree_sensitive(mem);
2922 	else
2923 		kfree(mem);
2924 	atomic_sub(size, &sk->sk_omem_alloc);
2925 }
2926 
2927 void sock_kfree_s(struct sock *sk, void *mem, int size)
2928 {
2929 	__sock_kfree_s(sk, mem, size, false);
2930 }
2931 EXPORT_SYMBOL(sock_kfree_s);
2932 
2933 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2934 {
2935 	__sock_kfree_s(sk, mem, size, true);
2936 }
2937 EXPORT_SYMBOL(sock_kzfree_s);
2938 
2939 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2940    I think, these locks should be removed for datagram sockets.
2941  */
2942 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2943 {
2944 	DEFINE_WAIT(wait);
2945 
2946 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2947 	for (;;) {
2948 		if (!timeo)
2949 			break;
2950 		if (signal_pending(current))
2951 			break;
2952 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2953 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2954 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2955 			break;
2956 		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2957 			break;
2958 		if (READ_ONCE(sk->sk_err))
2959 			break;
2960 		timeo = schedule_timeout(timeo);
2961 	}
2962 	finish_wait(sk_sleep(sk), &wait);
2963 	return timeo;
2964 }
2965 
2966 
2967 /*
2968  *	Generic send/receive buffer handlers
2969  */
2970 
2971 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2972 				     unsigned long data_len, int noblock,
2973 				     int *errcode, int max_page_order)
2974 {
2975 	struct sk_buff *skb;
2976 	long timeo;
2977 	int err;
2978 
2979 	timeo = sock_sndtimeo(sk, noblock);
2980 	for (;;) {
2981 		err = sock_error(sk);
2982 		if (err != 0)
2983 			goto failure;
2984 
2985 		err = -EPIPE;
2986 		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2987 			goto failure;
2988 
2989 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2990 			break;
2991 
2992 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2993 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2994 		err = -EAGAIN;
2995 		if (!timeo)
2996 			goto failure;
2997 		if (signal_pending(current))
2998 			goto interrupted;
2999 		timeo = sock_wait_for_wmem(sk, timeo);
3000 	}
3001 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
3002 				   errcode, sk->sk_allocation);
3003 	if (skb)
3004 		skb_set_owner_w(skb, sk);
3005 	return skb;
3006 
3007 interrupted:
3008 	err = sock_intr_errno(timeo);
3009 failure:
3010 	*errcode = err;
3011 	return NULL;
3012 }
3013 EXPORT_SYMBOL(sock_alloc_send_pskb);
3014 
3015 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
3016 		     struct sockcm_cookie *sockc)
3017 {
3018 	u32 tsflags;
3019 
3020 	BUILD_BUG_ON(SOF_TIMESTAMPING_LAST == (1 << 31));
3021 
3022 	switch (cmsg->cmsg_type) {
3023 	case SO_MARK:
3024 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
3025 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
3026 			return -EPERM;
3027 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3028 			return -EINVAL;
3029 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
3030 		break;
3031 	case SO_TIMESTAMPING_OLD:
3032 	case SO_TIMESTAMPING_NEW:
3033 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3034 			return -EINVAL;
3035 
3036 		tsflags = *(u32 *)CMSG_DATA(cmsg);
3037 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
3038 			return -EINVAL;
3039 
3040 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
3041 		sockc->tsflags |= tsflags;
3042 		break;
3043 	case SCM_TXTIME:
3044 		if (!sock_flag(sk, SOCK_TXTIME))
3045 			return -EINVAL;
3046 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
3047 			return -EINVAL;
3048 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
3049 		break;
3050 	case SCM_TS_OPT_ID:
3051 		if (sk_is_tcp(sk))
3052 			return -EINVAL;
3053 		tsflags = READ_ONCE(sk->sk_tsflags);
3054 		if (!(tsflags & SOF_TIMESTAMPING_OPT_ID))
3055 			return -EINVAL;
3056 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3057 			return -EINVAL;
3058 		sockc->ts_opt_id = *(u32 *)CMSG_DATA(cmsg);
3059 		sockc->tsflags |= SOCKCM_FLAG_TS_OPT_ID;
3060 		break;
3061 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
3062 	case SCM_RIGHTS:
3063 	case SCM_CREDENTIALS:
3064 		break;
3065 	case SO_PRIORITY:
3066 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3067 			return -EINVAL;
3068 		if (!sk_set_prio_allowed(sk, *(u32 *)CMSG_DATA(cmsg)))
3069 			return -EPERM;
3070 		sockc->priority = *(u32 *)CMSG_DATA(cmsg);
3071 		break;
3072 	case SCM_DEVMEM_DMABUF:
3073 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3074 			return -EINVAL;
3075 		sockc->dmabuf_id = *(u32 *)CMSG_DATA(cmsg);
3076 		break;
3077 	default:
3078 		return -EINVAL;
3079 	}
3080 	return 0;
3081 }
3082 EXPORT_SYMBOL(__sock_cmsg_send);
3083 
3084 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
3085 		   struct sockcm_cookie *sockc)
3086 {
3087 	struct cmsghdr *cmsg;
3088 	int ret;
3089 
3090 	for_each_cmsghdr(cmsg, msg) {
3091 		if (!CMSG_OK(msg, cmsg))
3092 			return -EINVAL;
3093 		if (cmsg->cmsg_level != SOL_SOCKET)
3094 			continue;
3095 		ret = __sock_cmsg_send(sk, cmsg, sockc);
3096 		if (ret)
3097 			return ret;
3098 	}
3099 	return 0;
3100 }
3101 EXPORT_SYMBOL(sock_cmsg_send);
3102 
3103 static void sk_enter_memory_pressure(struct sock *sk)
3104 {
3105 	if (!sk->sk_prot->enter_memory_pressure)
3106 		return;
3107 
3108 	sk->sk_prot->enter_memory_pressure(sk);
3109 }
3110 
3111 static void sk_leave_memory_pressure(struct sock *sk)
3112 {
3113 	if (sk->sk_prot->leave_memory_pressure) {
3114 		INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
3115 				     tcp_leave_memory_pressure, sk);
3116 	} else {
3117 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
3118 
3119 		if (memory_pressure && READ_ONCE(*memory_pressure))
3120 			WRITE_ONCE(*memory_pressure, 0);
3121 	}
3122 }
3123 
3124 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
3125 
3126 /**
3127  * skb_page_frag_refill - check that a page_frag contains enough room
3128  * @sz: minimum size of the fragment we want to get
3129  * @pfrag: pointer to page_frag
3130  * @gfp: priority for memory allocation
3131  *
3132  * Note: While this allocator tries to use high order pages, there is
3133  * no guarantee that allocations succeed. Therefore, @sz MUST be
3134  * less or equal than PAGE_SIZE.
3135  */
3136 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
3137 {
3138 	if (pfrag->page) {
3139 		if (page_ref_count(pfrag->page) == 1) {
3140 			pfrag->offset = 0;
3141 			return true;
3142 		}
3143 		if (pfrag->offset + sz <= pfrag->size)
3144 			return true;
3145 		put_page(pfrag->page);
3146 	}
3147 
3148 	pfrag->offset = 0;
3149 	if (SKB_FRAG_PAGE_ORDER &&
3150 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
3151 		/* Avoid direct reclaim but allow kswapd to wake */
3152 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
3153 					  __GFP_COMP | __GFP_NOWARN |
3154 					  __GFP_NORETRY,
3155 					  SKB_FRAG_PAGE_ORDER);
3156 		if (likely(pfrag->page)) {
3157 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
3158 			return true;
3159 		}
3160 	}
3161 	pfrag->page = alloc_page(gfp);
3162 	if (likely(pfrag->page)) {
3163 		pfrag->size = PAGE_SIZE;
3164 		return true;
3165 	}
3166 	return false;
3167 }
3168 EXPORT_SYMBOL(skb_page_frag_refill);
3169 
3170 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
3171 {
3172 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
3173 		return true;
3174 
3175 	if (!sk->sk_bypass_prot_mem)
3176 		sk_enter_memory_pressure(sk);
3177 
3178 	sk_stream_moderate_sndbuf(sk);
3179 
3180 	return false;
3181 }
3182 EXPORT_SYMBOL(sk_page_frag_refill);
3183 
3184 static void __lock_sock(struct sock *sk)
3185 	__releases(&sk->sk_lock.slock)
3186 	__acquires(&sk->sk_lock.slock)
3187 {
3188 	DEFINE_WAIT(wait);
3189 
3190 	for (;;) {
3191 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
3192 					TASK_UNINTERRUPTIBLE);
3193 		spin_unlock_bh(&sk->sk_lock.slock);
3194 		schedule();
3195 		spin_lock_bh(&sk->sk_lock.slock);
3196 		if (!sock_owned_by_user(sk))
3197 			break;
3198 	}
3199 	finish_wait(&sk->sk_lock.wq, &wait);
3200 }
3201 
3202 void __release_sock(struct sock *sk)
3203 	__releases(&sk->sk_lock.slock)
3204 	__acquires(&sk->sk_lock.slock)
3205 {
3206 	struct sk_buff *skb, *next;
3207 	int nb = 0;
3208 
3209 	while ((skb = sk->sk_backlog.head) != NULL) {
3210 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
3211 
3212 		spin_unlock_bh(&sk->sk_lock.slock);
3213 
3214 		while (1) {
3215 			next = skb->next;
3216 			prefetch(next);
3217 			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
3218 			skb_mark_not_on_list(skb);
3219 			sk_backlog_rcv(sk, skb);
3220 
3221 			skb = next;
3222 			if (!skb)
3223 				break;
3224 
3225 			if (!(++nb & 15))
3226 				cond_resched();
3227 		}
3228 
3229 		spin_lock_bh(&sk->sk_lock.slock);
3230 	}
3231 
3232 	/*
3233 	 * Doing the zeroing here guarantee we can not loop forever
3234 	 * while a wild producer attempts to flood us.
3235 	 */
3236 	sk->sk_backlog.len = 0;
3237 }
3238 
3239 void __sk_flush_backlog(struct sock *sk)
3240 {
3241 	spin_lock_bh(&sk->sk_lock.slock);
3242 	__release_sock(sk);
3243 
3244 	if (sk->sk_prot->release_cb)
3245 		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3246 				     tcp_release_cb, sk);
3247 
3248 	spin_unlock_bh(&sk->sk_lock.slock);
3249 }
3250 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3251 
3252 /**
3253  * sk_wait_data - wait for data to arrive at sk_receive_queue
3254  * @sk:    sock to wait on
3255  * @timeo: for how long
3256  * @skb:   last skb seen on sk_receive_queue
3257  *
3258  * Now socket state including sk->sk_err is changed only under lock,
3259  * hence we may omit checks after joining wait queue.
3260  * We check receive queue before schedule() only as optimization;
3261  * it is very likely that release_sock() added new data.
3262  */
3263 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3264 {
3265 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
3266 	int rc;
3267 
3268 	add_wait_queue(sk_sleep(sk), &wait);
3269 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3270 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3271 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3272 	remove_wait_queue(sk_sleep(sk), &wait);
3273 	return rc;
3274 }
3275 EXPORT_SYMBOL(sk_wait_data);
3276 
3277 /**
3278  *	__sk_mem_raise_allocated - increase memory_allocated
3279  *	@sk: socket
3280  *	@size: memory size to allocate
3281  *	@amt: pages to allocate
3282  *	@kind: allocation type
3283  *
3284  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3285  *
3286  *	Unlike the globally shared limits among the sockets under same protocol,
3287  *	consuming the budget of a memcg won't have direct effect on other ones.
3288  *	So be optimistic about memcg's tolerance, and leave the callers to decide
3289  *	whether or not to raise allocated through sk_under_memory_pressure() or
3290  *	its variants.
3291  */
3292 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3293 {
3294 	bool memcg_enabled = false, charged = false;
3295 	struct proto *prot = sk->sk_prot;
3296 	long allocated = 0;
3297 
3298 	if (!sk->sk_bypass_prot_mem) {
3299 		sk_memory_allocated_add(sk, amt);
3300 		allocated = sk_memory_allocated(sk);
3301 	}
3302 
3303 	if (mem_cgroup_sk_enabled(sk)) {
3304 		memcg_enabled = true;
3305 		charged = mem_cgroup_sk_charge(sk, amt, gfp_memcg_charge());
3306 		if (!charged)
3307 			goto suppress_allocation;
3308 	}
3309 
3310 	if (!allocated)
3311 		return 1;
3312 
3313 	/* Under limit. */
3314 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
3315 		sk_leave_memory_pressure(sk);
3316 		return 1;
3317 	}
3318 
3319 	/* Under pressure. */
3320 	if (allocated > sk_prot_mem_limits(sk, 1))
3321 		sk_enter_memory_pressure(sk);
3322 
3323 	/* Over hard limit. */
3324 	if (allocated > sk_prot_mem_limits(sk, 2))
3325 		goto suppress_allocation;
3326 
3327 	/* Guarantee minimum buffer size under pressure (either global
3328 	 * or memcg) to make sure features described in RFC 7323 (TCP
3329 	 * Extensions for High Performance) work properly.
3330 	 *
3331 	 * This rule does NOT stand when exceeds global or memcg's hard
3332 	 * limit, or else a DoS attack can be taken place by spawning
3333 	 * lots of sockets whose usage are under minimum buffer size.
3334 	 */
3335 	if (kind == SK_MEM_RECV) {
3336 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3337 			return 1;
3338 
3339 	} else { /* SK_MEM_SEND */
3340 		int wmem0 = sk_get_wmem0(sk, prot);
3341 
3342 		if (sk->sk_type == SOCK_STREAM) {
3343 			if (sk->sk_wmem_queued < wmem0)
3344 				return 1;
3345 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3346 				return 1;
3347 		}
3348 	}
3349 
3350 	if (sk_has_memory_pressure(sk)) {
3351 		u64 alloc;
3352 
3353 		/* The following 'average' heuristic is within the
3354 		 * scope of global accounting, so it only makes
3355 		 * sense for global memory pressure.
3356 		 */
3357 		if (!sk_under_global_memory_pressure(sk))
3358 			return 1;
3359 
3360 		/* Try to be fair among all the sockets under global
3361 		 * pressure by allowing the ones that below average
3362 		 * usage to raise.
3363 		 */
3364 		alloc = sk_sockets_allocated_read_positive(sk);
3365 		if (sk_prot_mem_limits(sk, 2) > alloc *
3366 		    sk_mem_pages(sk->sk_wmem_queued +
3367 				 atomic_read(&sk->sk_rmem_alloc) +
3368 				 sk->sk_forward_alloc))
3369 			return 1;
3370 	}
3371 
3372 suppress_allocation:
3373 
3374 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3375 		sk_stream_moderate_sndbuf(sk);
3376 
3377 		/* Fail only if socket is _under_ its sndbuf.
3378 		 * In this case we cannot block, so that we have to fail.
3379 		 */
3380 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3381 			/* Force charge with __GFP_NOFAIL */
3382 			if (memcg_enabled && !charged)
3383 				mem_cgroup_sk_charge(sk, amt,
3384 						     gfp_memcg_charge() | __GFP_NOFAIL);
3385 			return 1;
3386 		}
3387 	}
3388 
3389 	trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3390 
3391 	if (allocated)
3392 		sk_memory_allocated_sub(sk, amt);
3393 
3394 	if (charged)
3395 		mem_cgroup_sk_uncharge(sk, amt);
3396 
3397 	return 0;
3398 }
3399 
3400 /**
3401  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3402  *	@sk: socket
3403  *	@size: memory size to allocate
3404  *	@kind: allocation type
3405  *
3406  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3407  *	rmem allocation. This function assumes that protocols which have
3408  *	memory_pressure use sk_wmem_queued as write buffer accounting.
3409  */
3410 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3411 {
3412 	int ret, amt = sk_mem_pages(size);
3413 
3414 	sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3415 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3416 	if (!ret)
3417 		sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3418 	return ret;
3419 }
3420 EXPORT_SYMBOL(__sk_mem_schedule);
3421 
3422 /**
3423  *	__sk_mem_reduce_allocated - reclaim memory_allocated
3424  *	@sk: socket
3425  *	@amount: number of quanta
3426  *
3427  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3428  */
3429 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3430 {
3431 	if (mem_cgroup_sk_enabled(sk))
3432 		mem_cgroup_sk_uncharge(sk, amount);
3433 
3434 	if (sk->sk_bypass_prot_mem)
3435 		return;
3436 
3437 	sk_memory_allocated_sub(sk, amount);
3438 
3439 	if (sk_under_global_memory_pressure(sk) &&
3440 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3441 		sk_leave_memory_pressure(sk);
3442 }
3443 
3444 /**
3445  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3446  *	@sk: socket
3447  *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3448  */
3449 void __sk_mem_reclaim(struct sock *sk, int amount)
3450 {
3451 	amount >>= PAGE_SHIFT;
3452 	sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3453 	__sk_mem_reduce_allocated(sk, amount);
3454 }
3455 EXPORT_SYMBOL(__sk_mem_reclaim);
3456 
3457 void __sk_charge(struct sock *sk, gfp_t gfp)
3458 {
3459 	int amt;
3460 
3461 	gfp |= __GFP_NOFAIL;
3462 	if (mem_cgroup_from_sk(sk)) {
3463 		/* The socket has not been accepted yet, no need
3464 		 * to look at newsk->sk_wmem_queued.
3465 		 */
3466 		amt = sk_mem_pages(sk->sk_forward_alloc +
3467 				   atomic_read(&sk->sk_rmem_alloc));
3468 		if (amt)
3469 			mem_cgroup_sk_charge(sk, amt, gfp);
3470 	}
3471 
3472 	kmem_cache_charge(sk, gfp);
3473 }
3474 
3475 int sk_set_peek_off(struct sock *sk, int val)
3476 {
3477 	WRITE_ONCE(sk->sk_peek_off, val);
3478 	return 0;
3479 }
3480 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3481 
3482 /*
3483  * Set of default routines for initialising struct proto_ops when
3484  * the protocol does not support a particular function. In certain
3485  * cases where it makes no sense for a protocol to have a "do nothing"
3486  * function, some default processing is provided.
3487  */
3488 
3489 int sock_no_bind(struct socket *sock, struct sockaddr_unsized *saddr, int len)
3490 {
3491 	return -EOPNOTSUPP;
3492 }
3493 EXPORT_SYMBOL(sock_no_bind);
3494 
3495 int sock_no_connect(struct socket *sock, struct sockaddr_unsized *saddr,
3496 		    int len, int flags)
3497 {
3498 	return -EOPNOTSUPP;
3499 }
3500 EXPORT_SYMBOL(sock_no_connect);
3501 
3502 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3503 {
3504 	return -EOPNOTSUPP;
3505 }
3506 EXPORT_SYMBOL(sock_no_socketpair);
3507 
3508 int sock_no_accept(struct socket *sock, struct socket *newsock,
3509 		   struct proto_accept_arg *arg)
3510 {
3511 	return -EOPNOTSUPP;
3512 }
3513 EXPORT_SYMBOL(sock_no_accept);
3514 
3515 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3516 		    int peer)
3517 {
3518 	return -EOPNOTSUPP;
3519 }
3520 EXPORT_SYMBOL(sock_no_getname);
3521 
3522 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3523 {
3524 	return -EOPNOTSUPP;
3525 }
3526 EXPORT_SYMBOL(sock_no_ioctl);
3527 
3528 int sock_no_listen(struct socket *sock, int backlog)
3529 {
3530 	return -EOPNOTSUPP;
3531 }
3532 EXPORT_SYMBOL(sock_no_listen);
3533 
3534 int sock_no_shutdown(struct socket *sock, int how)
3535 {
3536 	return -EOPNOTSUPP;
3537 }
3538 EXPORT_SYMBOL(sock_no_shutdown);
3539 
3540 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3541 {
3542 	return -EOPNOTSUPP;
3543 }
3544 EXPORT_SYMBOL(sock_no_sendmsg);
3545 
3546 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3547 {
3548 	return -EOPNOTSUPP;
3549 }
3550 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3551 
3552 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3553 		    int flags)
3554 {
3555 	return -EOPNOTSUPP;
3556 }
3557 EXPORT_SYMBOL(sock_no_recvmsg);
3558 
3559 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3560 {
3561 	/* Mirror missing mmap method error code */
3562 	return -ENODEV;
3563 }
3564 EXPORT_SYMBOL(sock_no_mmap);
3565 
3566 /*
3567  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3568  * various sock-based usage counts.
3569  */
3570 void __receive_sock(struct file *file)
3571 {
3572 	struct socket *sock;
3573 
3574 	sock = sock_from_file(file);
3575 	if (sock) {
3576 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3577 		sock_update_classid(&sock->sk->sk_cgrp_data);
3578 	}
3579 }
3580 
3581 /*
3582  *	Default Socket Callbacks
3583  */
3584 
3585 static void sock_def_wakeup(struct sock *sk)
3586 {
3587 	struct socket_wq *wq;
3588 
3589 	rcu_read_lock();
3590 	wq = rcu_dereference(sk->sk_wq);
3591 	if (skwq_has_sleeper(wq))
3592 		wake_up_interruptible_all(&wq->wait);
3593 	rcu_read_unlock();
3594 }
3595 
3596 static void sock_def_error_report(struct sock *sk)
3597 {
3598 	struct socket_wq *wq;
3599 
3600 	rcu_read_lock();
3601 	wq = rcu_dereference(sk->sk_wq);
3602 	if (skwq_has_sleeper(wq))
3603 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3604 	sk_wake_async_rcu(sk, SOCK_WAKE_IO, POLL_ERR);
3605 	rcu_read_unlock();
3606 }
3607 
3608 void sock_def_readable(struct sock *sk)
3609 {
3610 	struct socket_wq *wq;
3611 
3612 	trace_sk_data_ready(sk);
3613 
3614 	rcu_read_lock();
3615 	wq = rcu_dereference(sk->sk_wq);
3616 	if (skwq_has_sleeper(wq))
3617 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3618 						EPOLLRDNORM | EPOLLRDBAND);
3619 	sk_wake_async_rcu(sk, SOCK_WAKE_WAITD, POLL_IN);
3620 	rcu_read_unlock();
3621 }
3622 
3623 static void sock_def_write_space(struct sock *sk)
3624 {
3625 	struct socket_wq *wq;
3626 
3627 	rcu_read_lock();
3628 
3629 	/* Do not wake up a writer until he can make "significant"
3630 	 * progress.  --DaveM
3631 	 */
3632 	if (sock_writeable(sk)) {
3633 		wq = rcu_dereference(sk->sk_wq);
3634 		if (skwq_has_sleeper(wq))
3635 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3636 						EPOLLWRNORM | EPOLLWRBAND);
3637 
3638 		/* Should agree with poll, otherwise some programs break */
3639 		sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3640 	}
3641 
3642 	rcu_read_unlock();
3643 }
3644 
3645 /* An optimised version of sock_def_write_space(), should only be called
3646  * for SOCK_RCU_FREE sockets under RCU read section and after putting
3647  * ->sk_wmem_alloc.
3648  */
3649 static void sock_def_write_space_wfree(struct sock *sk, int wmem_alloc)
3650 {
3651 	/* Do not wake up a writer until he can make "significant"
3652 	 * progress.  --DaveM
3653 	 */
3654 	if (__sock_writeable(sk, wmem_alloc)) {
3655 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3656 
3657 		/* rely on refcount_sub from sock_wfree() */
3658 		smp_mb__after_atomic();
3659 		if (wq && waitqueue_active(&wq->wait))
3660 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3661 						EPOLLWRNORM | EPOLLWRBAND);
3662 
3663 		/* Should agree with poll, otherwise some programs break */
3664 		sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3665 	}
3666 }
3667 
3668 static void sock_def_destruct(struct sock *sk)
3669 {
3670 }
3671 
3672 void sk_send_sigurg(struct sock *sk)
3673 {
3674 	if (sk->sk_socket && sk->sk_socket->file)
3675 		if (send_sigurg(sk->sk_socket->file))
3676 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3677 }
3678 EXPORT_SYMBOL(sk_send_sigurg);
3679 
3680 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3681 		    unsigned long expires)
3682 {
3683 	if (!mod_timer(timer, expires))
3684 		sock_hold(sk);
3685 }
3686 EXPORT_SYMBOL(sk_reset_timer);
3687 
3688 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3689 {
3690 	if (timer_delete(timer))
3691 		__sock_put(sk);
3692 }
3693 EXPORT_SYMBOL(sk_stop_timer);
3694 
3695 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3696 {
3697 	if (timer_delete_sync(timer))
3698 		__sock_put(sk);
3699 }
3700 EXPORT_SYMBOL(sk_stop_timer_sync);
3701 
3702 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3703 {
3704 	sk_init_common(sk);
3705 	sk->sk_send_head	=	NULL;
3706 
3707 	timer_setup(&sk->sk_timer, NULL, 0);
3708 
3709 	sk->sk_allocation	=	GFP_KERNEL;
3710 	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3711 	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3712 	sk->sk_state		=	TCP_CLOSE;
3713 	sk->sk_use_task_frag	=	true;
3714 	sk_set_socket(sk, sock);
3715 
3716 	sock_set_flag(sk, SOCK_ZAPPED);
3717 
3718 	if (sock) {
3719 		sk->sk_type	=	sock->type;
3720 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3721 		sock->sk	=	sk;
3722 	} else {
3723 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3724 	}
3725 	sk->sk_uid	=	uid;
3726 
3727 	sk->sk_state_change	=	sock_def_wakeup;
3728 	sk->sk_data_ready	=	sock_def_readable;
3729 	sk->sk_write_space	=	sock_def_write_space;
3730 	sk->sk_error_report	=	sock_def_error_report;
3731 	sk->sk_destruct		=	sock_def_destruct;
3732 
3733 	sk->sk_frag.page	=	NULL;
3734 	sk->sk_frag.offset	=	0;
3735 	sk->sk_peek_off		=	-1;
3736 
3737 	sk->sk_peer_pid 	=	NULL;
3738 	sk->sk_peer_cred	=	NULL;
3739 	spin_lock_init(&sk->sk_peer_lock);
3740 
3741 	sk->sk_write_pending	=	0;
3742 	sk->sk_rcvlowat		=	1;
3743 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3744 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3745 
3746 	sk->sk_stamp = SK_DEFAULT_STAMP;
3747 #if BITS_PER_LONG==32
3748 	seqlock_init(&sk->sk_stamp_seq);
3749 #endif
3750 	atomic_set(&sk->sk_zckey, 0);
3751 
3752 #ifdef CONFIG_NET_RX_BUSY_POLL
3753 	sk->sk_napi_id		=	0;
3754 	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3755 #endif
3756 
3757 	sk->sk_max_pacing_rate = ~0UL;
3758 	sk->sk_pacing_rate = ~0UL;
3759 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3760 	sk->sk_incoming_cpu = -1;
3761 
3762 	sk_rx_queue_clear(sk);
3763 	/*
3764 	 * Before updating sk_refcnt, we must commit prior changes to memory
3765 	 * (Documentation/RCU/rculist_nulls.rst for details)
3766 	 */
3767 	smp_wmb();
3768 	refcount_set(&sk->sk_refcnt, 1);
3769 	sk_drops_reset(sk);
3770 }
3771 EXPORT_SYMBOL(sock_init_data_uid);
3772 
3773 void sock_init_data(struct socket *sock, struct sock *sk)
3774 {
3775 	kuid_t uid = sock ?
3776 		SOCK_INODE(sock)->i_uid :
3777 		make_kuid(sock_net(sk)->user_ns, 0);
3778 
3779 	sock_init_data_uid(sock, sk, uid);
3780 }
3781 EXPORT_SYMBOL(sock_init_data);
3782 
3783 void noinline lock_sock_nested(struct sock *sk, int subclass)
3784 {
3785 	/* The sk_lock has mutex_lock() semantics here. */
3786 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3787 
3788 	might_sleep();
3789 #ifdef CONFIG_64BIT
3790 	if (sizeof(struct slock_owned) == sizeof(long)) {
3791 		socket_lock_t tmp = {
3792 			.slock = __SPIN_LOCK_UNLOCKED(tmp.slock),
3793 			.owned = 1,
3794 		};
3795 		socket_lock_t old = {
3796 			.slock = __SPIN_LOCK_UNLOCKED(old.slock),
3797 			.owned = 0,
3798 		};
3799 
3800 		if (likely(try_cmpxchg(&sk->sk_lock.combined,
3801 				       &old.combined, tmp.combined)))
3802 			return;
3803 	}
3804 #endif
3805 	spin_lock_bh(&sk->sk_lock.slock);
3806 	if (unlikely(sock_owned_by_user_nocheck(sk)))
3807 		__lock_sock(sk);
3808 	sk->sk_lock.owned = 1;
3809 	spin_unlock_bh(&sk->sk_lock.slock);
3810 }
3811 EXPORT_SYMBOL(lock_sock_nested);
3812 
3813 void release_sock(struct sock *sk)
3814 {
3815 	spin_lock_bh(&sk->sk_lock.slock);
3816 
3817 	if (unlikely(sk->sk_backlog.tail))
3818 		__release_sock(sk);
3819 
3820 	if (sk->sk_prot->release_cb) {
3821 		if (!tcp_release_cb_cond(sk))
3822 			sk->sk_prot->release_cb(sk);
3823 	}
3824 	sock_release_ownership(sk);
3825 	if (unlikely(waitqueue_active(&sk->sk_lock.wq)))
3826 		wake_up(&sk->sk_lock.wq);
3827 
3828 	spin_unlock_bh(&sk->sk_lock.slock);
3829 }
3830 EXPORT_SYMBOL(release_sock);
3831 
3832 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3833 {
3834 	might_sleep();
3835 	spin_lock_bh(&sk->sk_lock.slock);
3836 
3837 	if (likely(!sock_owned_by_user_nocheck(sk))) {
3838 		/*
3839 		 * Fast path return with bottom halves disabled and
3840 		 * sock::sk_lock.slock held.
3841 		 *
3842 		 * The 'mutex' is not contended and holding
3843 		 * sock::sk_lock.slock prevents all other lockers to
3844 		 * proceed so the corresponding unlock_sock_fast() can
3845 		 * avoid the slow path of release_sock() completely and
3846 		 * just release slock.
3847 		 *
3848 		 * From a semantical POV this is equivalent to 'acquiring'
3849 		 * the 'mutex', hence the corresponding lockdep
3850 		 * mutex_release() has to happen in the fast path of
3851 		 * unlock_sock_fast().
3852 		 */
3853 		return false;
3854 	}
3855 
3856 	__lock_sock(sk);
3857 	sk->sk_lock.owned = 1;
3858 	__acquire(&sk->sk_lock.slock);
3859 	spin_unlock_bh(&sk->sk_lock.slock);
3860 	return true;
3861 }
3862 EXPORT_SYMBOL(__lock_sock_fast);
3863 
3864 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3865 		   bool timeval, bool time32)
3866 {
3867 	struct sock *sk = sock->sk;
3868 	struct timespec64 ts;
3869 
3870 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3871 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3872 	if (ts.tv_sec == -1)
3873 		return -ENOENT;
3874 	if (ts.tv_sec == 0) {
3875 		ktime_t kt = ktime_get_real();
3876 		sock_write_timestamp(sk, kt);
3877 		ts = ktime_to_timespec64(kt);
3878 	}
3879 
3880 	if (timeval)
3881 		ts.tv_nsec /= 1000;
3882 
3883 #ifdef CONFIG_COMPAT_32BIT_TIME
3884 	if (time32)
3885 		return put_old_timespec32(&ts, userstamp);
3886 #endif
3887 #ifdef CONFIG_SPARC64
3888 	/* beware of padding in sparc64 timeval */
3889 	if (timeval && !in_compat_syscall()) {
3890 		struct __kernel_old_timeval __user tv = {
3891 			.tv_sec = ts.tv_sec,
3892 			.tv_usec = ts.tv_nsec,
3893 		};
3894 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3895 			return -EFAULT;
3896 		return 0;
3897 	}
3898 #endif
3899 	return put_timespec64(&ts, userstamp);
3900 }
3901 EXPORT_SYMBOL(sock_gettstamp);
3902 
3903 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3904 {
3905 	if (!sock_flag(sk, flag)) {
3906 		unsigned long previous_flags = sk->sk_flags;
3907 
3908 		sock_set_flag(sk, flag);
3909 		/*
3910 		 * we just set one of the two flags which require net
3911 		 * time stamping, but time stamping might have been on
3912 		 * already because of the other one
3913 		 */
3914 		if (sock_needs_netstamp(sk) &&
3915 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3916 			net_enable_timestamp();
3917 	}
3918 }
3919 
3920 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3921 		       int level, int type)
3922 {
3923 	struct sock_extended_err ee;
3924 	struct sk_buff *skb;
3925 	int copied, err;
3926 
3927 	err = -EAGAIN;
3928 	skb = sock_dequeue_err_skb(sk);
3929 	if (skb == NULL)
3930 		goto out;
3931 
3932 	copied = skb->len;
3933 	if (copied > len) {
3934 		msg->msg_flags |= MSG_TRUNC;
3935 		copied = len;
3936 	}
3937 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3938 	if (err)
3939 		goto out_free_skb;
3940 
3941 	sock_recv_timestamp(msg, sk, skb);
3942 
3943 	/* We must use a bounce buffer for CONFIG_HARDENED_USERCOPY=y */
3944 	ee = SKB_EXT_ERR(skb)->ee;
3945 	put_cmsg(msg, level, type, sizeof(ee), &ee);
3946 
3947 	msg->msg_flags |= MSG_ERRQUEUE;
3948 	err = copied;
3949 
3950 out_free_skb:
3951 	kfree_skb(skb);
3952 out:
3953 	return err;
3954 }
3955 EXPORT_SYMBOL(sock_recv_errqueue);
3956 
3957 /*
3958  *	Get a socket option on an socket.
3959  *
3960  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3961  *	asynchronous errors should be reported by getsockopt. We assume
3962  *	this means if you specify SO_ERROR (otherwise what is the point of it).
3963  */
3964 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3965 			   char __user *optval, int __user *optlen)
3966 {
3967 	struct sock *sk = sock->sk;
3968 
3969 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3970 	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3971 }
3972 EXPORT_SYMBOL(sock_common_getsockopt);
3973 
3974 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3975 			int flags)
3976 {
3977 	struct sock *sk = sock->sk;
3978 
3979 	return sk->sk_prot->recvmsg(sk, msg, size, flags);
3980 }
3981 EXPORT_SYMBOL(sock_common_recvmsg);
3982 
3983 /*
3984  *	Set socket options on an inet socket.
3985  */
3986 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3987 			   sockptr_t optval, unsigned int optlen)
3988 {
3989 	struct sock *sk = sock->sk;
3990 
3991 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3992 	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3993 }
3994 EXPORT_SYMBOL(sock_common_setsockopt);
3995 
3996 void sk_common_release(struct sock *sk)
3997 {
3998 	if (sk->sk_prot->destroy)
3999 		sk->sk_prot->destroy(sk);
4000 
4001 	/*
4002 	 * Observation: when sk_common_release is called, processes have
4003 	 * no access to socket. But net still has.
4004 	 * Step one, detach it from networking:
4005 	 *
4006 	 * A. Remove from hash tables.
4007 	 */
4008 
4009 	sk->sk_prot->unhash(sk);
4010 
4011 	/*
4012 	 * In this point socket cannot receive new packets, but it is possible
4013 	 * that some packets are in flight because some CPU runs receiver and
4014 	 * did hash table lookup before we unhashed socket. They will achieve
4015 	 * receive queue and will be purged by socket destructor.
4016 	 *
4017 	 * Also we still have packets pending on receive queue and probably,
4018 	 * our own packets waiting in device queues. sock_destroy will drain
4019 	 * receive queue, but transmitted packets will delay socket destruction
4020 	 * until the last reference will be released.
4021 	 */
4022 
4023 	sock_orphan(sk);
4024 
4025 	xfrm_sk_free_policy(sk);
4026 
4027 	sock_put(sk);
4028 }
4029 EXPORT_SYMBOL(sk_common_release);
4030 
4031 void sk_get_meminfo(const struct sock *sk, u32 *mem)
4032 {
4033 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
4034 
4035 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
4036 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
4037 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
4038 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
4039 	mem[SK_MEMINFO_FWD_ALLOC] = READ_ONCE(sk->sk_forward_alloc);
4040 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
4041 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
4042 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
4043 	mem[SK_MEMINFO_DROPS] = sk_drops_read(sk);
4044 }
4045 
4046 #ifdef CONFIG_PROC_FS
4047 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
4048 
4049 int sock_prot_inuse_get(struct net *net, struct proto *prot)
4050 {
4051 	int cpu, idx = prot->inuse_idx;
4052 	int res = 0;
4053 
4054 	for_each_possible_cpu(cpu)
4055 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
4056 
4057 	return res >= 0 ? res : 0;
4058 }
4059 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
4060 
4061 int sock_inuse_get(struct net *net)
4062 {
4063 	int cpu, res = 0;
4064 
4065 	for_each_possible_cpu(cpu)
4066 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
4067 
4068 	return res;
4069 }
4070 
4071 EXPORT_SYMBOL_GPL(sock_inuse_get);
4072 
4073 static int __net_init sock_inuse_init_net(struct net *net)
4074 {
4075 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
4076 	if (net->core.prot_inuse == NULL)
4077 		return -ENOMEM;
4078 	return 0;
4079 }
4080 
4081 static void __net_exit sock_inuse_exit_net(struct net *net)
4082 {
4083 	free_percpu(net->core.prot_inuse);
4084 }
4085 
4086 static struct pernet_operations net_inuse_ops = {
4087 	.init = sock_inuse_init_net,
4088 	.exit = sock_inuse_exit_net,
4089 };
4090 
4091 static __init int net_inuse_init(void)
4092 {
4093 	if (register_pernet_subsys(&net_inuse_ops))
4094 		panic("Cannot initialize net inuse counters");
4095 
4096 	return 0;
4097 }
4098 
4099 core_initcall(net_inuse_init);
4100 
4101 static int assign_proto_idx(struct proto *prot)
4102 {
4103 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
4104 
4105 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR)) {
4106 		pr_err("PROTO_INUSE_NR exhausted\n");
4107 		return -ENOSPC;
4108 	}
4109 
4110 	set_bit(prot->inuse_idx, proto_inuse_idx);
4111 	return 0;
4112 }
4113 
4114 static void release_proto_idx(struct proto *prot)
4115 {
4116 	if (prot->inuse_idx != PROTO_INUSE_NR)
4117 		clear_bit(prot->inuse_idx, proto_inuse_idx);
4118 }
4119 #else
4120 static inline int assign_proto_idx(struct proto *prot)
4121 {
4122 	return 0;
4123 }
4124 
4125 static inline void release_proto_idx(struct proto *prot)
4126 {
4127 }
4128 
4129 #endif
4130 
4131 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
4132 {
4133 	if (!twsk_prot)
4134 		return;
4135 	kfree(twsk_prot->twsk_slab_name);
4136 	twsk_prot->twsk_slab_name = NULL;
4137 	kmem_cache_destroy(twsk_prot->twsk_slab);
4138 	twsk_prot->twsk_slab = NULL;
4139 }
4140 
4141 static int tw_prot_init(const struct proto *prot)
4142 {
4143 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
4144 
4145 	if (!twsk_prot)
4146 		return 0;
4147 
4148 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
4149 					      prot->name);
4150 	if (!twsk_prot->twsk_slab_name)
4151 		return -ENOMEM;
4152 
4153 	twsk_prot->twsk_slab =
4154 		kmem_cache_create(twsk_prot->twsk_slab_name,
4155 				  twsk_prot->twsk_obj_size, 0,
4156 				  SLAB_ACCOUNT | prot->slab_flags,
4157 				  NULL);
4158 	if (!twsk_prot->twsk_slab) {
4159 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
4160 			prot->name);
4161 		return -ENOMEM;
4162 	}
4163 
4164 	return 0;
4165 }
4166 
4167 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
4168 {
4169 	if (!rsk_prot)
4170 		return;
4171 	kfree(rsk_prot->slab_name);
4172 	rsk_prot->slab_name = NULL;
4173 	kmem_cache_destroy(rsk_prot->slab);
4174 	rsk_prot->slab = NULL;
4175 }
4176 
4177 static int req_prot_init(const struct proto *prot)
4178 {
4179 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
4180 
4181 	if (!rsk_prot)
4182 		return 0;
4183 
4184 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
4185 					prot->name);
4186 	if (!rsk_prot->slab_name)
4187 		return -ENOMEM;
4188 
4189 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
4190 					   rsk_prot->obj_size, 0,
4191 					   SLAB_ACCOUNT | prot->slab_flags,
4192 					   NULL);
4193 
4194 	if (!rsk_prot->slab) {
4195 		pr_crit("%s: Can't create request sock SLAB cache!\n",
4196 			prot->name);
4197 		return -ENOMEM;
4198 	}
4199 	return 0;
4200 }
4201 
4202 int proto_register(struct proto *prot, int alloc_slab)
4203 {
4204 	int ret = -ENOBUFS;
4205 
4206 	if (prot->memory_allocated && !prot->sysctl_mem) {
4207 		pr_err("%s: missing sysctl_mem\n", prot->name);
4208 		return -EINVAL;
4209 	}
4210 	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
4211 		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
4212 		return -EINVAL;
4213 	}
4214 	if (alloc_slab) {
4215 		struct kmem_cache_args args = {
4216 			.useroffset	= prot->useroffset,
4217 			.usersize	= prot->usersize,
4218 			.freeptr_offset = prot->freeptr_offset,
4219 			.use_freeptr_offset = !!prot->freeptr_offset,
4220 		};
4221 
4222 		prot->slab = kmem_cache_create(prot->name, prot->obj_size,
4223 					&args,
4224 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
4225 					prot->slab_flags);
4226 		if (prot->slab == NULL) {
4227 			pr_crit("%s: Can't create sock SLAB cache!\n",
4228 				prot->name);
4229 			goto out;
4230 		}
4231 
4232 		if (req_prot_init(prot))
4233 			goto out_free_request_sock_slab;
4234 
4235 		if (tw_prot_init(prot))
4236 			goto out_free_timewait_sock_slab;
4237 	}
4238 
4239 	mutex_lock(&proto_list_mutex);
4240 	ret = assign_proto_idx(prot);
4241 	if (ret) {
4242 		mutex_unlock(&proto_list_mutex);
4243 		goto out_free_timewait_sock_slab;
4244 	}
4245 	list_add(&prot->node, &proto_list);
4246 	mutex_unlock(&proto_list_mutex);
4247 	return ret;
4248 
4249 out_free_timewait_sock_slab:
4250 	if (alloc_slab)
4251 		tw_prot_cleanup(prot->twsk_prot);
4252 out_free_request_sock_slab:
4253 	if (alloc_slab) {
4254 		req_prot_cleanup(prot->rsk_prot);
4255 
4256 		kmem_cache_destroy(prot->slab);
4257 		prot->slab = NULL;
4258 	}
4259 out:
4260 	return ret;
4261 }
4262 EXPORT_SYMBOL(proto_register);
4263 
4264 void proto_unregister(struct proto *prot)
4265 {
4266 	mutex_lock(&proto_list_mutex);
4267 	release_proto_idx(prot);
4268 	list_del(&prot->node);
4269 	mutex_unlock(&proto_list_mutex);
4270 
4271 	kmem_cache_destroy(prot->slab);
4272 	prot->slab = NULL;
4273 
4274 	req_prot_cleanup(prot->rsk_prot);
4275 	tw_prot_cleanup(prot->twsk_prot);
4276 }
4277 EXPORT_SYMBOL(proto_unregister);
4278 
4279 int sock_load_diag_module(int family, int protocol)
4280 {
4281 	if (!protocol) {
4282 		if (!sock_is_registered(family))
4283 			return -ENOENT;
4284 
4285 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4286 				      NETLINK_SOCK_DIAG, family);
4287 	}
4288 
4289 #ifdef CONFIG_INET
4290 	if (family == AF_INET &&
4291 	    protocol != IPPROTO_RAW &&
4292 	    protocol < MAX_INET_PROTOS &&
4293 	    !rcu_access_pointer(inet_protos[protocol]))
4294 		return -ENOENT;
4295 #endif
4296 
4297 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4298 			      NETLINK_SOCK_DIAG, family, protocol);
4299 }
4300 EXPORT_SYMBOL(sock_load_diag_module);
4301 
4302 #ifdef CONFIG_PROC_FS
4303 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4304 	__acquires(proto_list_mutex)
4305 {
4306 	mutex_lock(&proto_list_mutex);
4307 	return seq_list_start_head(&proto_list, *pos);
4308 }
4309 
4310 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4311 {
4312 	return seq_list_next(v, &proto_list, pos);
4313 }
4314 
4315 static void proto_seq_stop(struct seq_file *seq, void *v)
4316 	__releases(proto_list_mutex)
4317 {
4318 	mutex_unlock(&proto_list_mutex);
4319 }
4320 
4321 static char proto_method_implemented(const void *method)
4322 {
4323 	return method == NULL ? 'n' : 'y';
4324 }
4325 static long sock_prot_memory_allocated(struct proto *proto)
4326 {
4327 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4328 }
4329 
4330 static const char *sock_prot_memory_pressure(struct proto *proto)
4331 {
4332 	return proto->memory_pressure != NULL ?
4333 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4334 }
4335 
4336 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4337 {
4338 
4339 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4340 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4341 		   proto->name,
4342 		   proto->obj_size,
4343 		   sock_prot_inuse_get(seq_file_net(seq), proto),
4344 		   sock_prot_memory_allocated(proto),
4345 		   sock_prot_memory_pressure(proto),
4346 		   proto->max_header,
4347 		   proto->slab == NULL ? "no" : "yes",
4348 		   module_name(proto->owner),
4349 		   proto_method_implemented(proto->close),
4350 		   proto_method_implemented(proto->connect),
4351 		   proto_method_implemented(proto->disconnect),
4352 		   proto_method_implemented(proto->accept),
4353 		   proto_method_implemented(proto->ioctl),
4354 		   proto_method_implemented(proto->init),
4355 		   proto_method_implemented(proto->destroy),
4356 		   proto_method_implemented(proto->shutdown),
4357 		   proto_method_implemented(proto->setsockopt),
4358 		   proto_method_implemented(proto->getsockopt),
4359 		   proto_method_implemented(proto->sendmsg),
4360 		   proto_method_implemented(proto->recvmsg),
4361 		   proto_method_implemented(proto->bind),
4362 		   proto_method_implemented(proto->backlog_rcv),
4363 		   proto_method_implemented(proto->hash),
4364 		   proto_method_implemented(proto->unhash),
4365 		   proto_method_implemented(proto->get_port),
4366 		   proto_method_implemented(proto->enter_memory_pressure));
4367 }
4368 
4369 static int proto_seq_show(struct seq_file *seq, void *v)
4370 {
4371 	if (v == &proto_list)
4372 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4373 			   "protocol",
4374 			   "size",
4375 			   "sockets",
4376 			   "memory",
4377 			   "press",
4378 			   "maxhdr",
4379 			   "slab",
4380 			   "module",
4381 			   "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4382 	else
4383 		proto_seq_printf(seq, list_entry(v, struct proto, node));
4384 	return 0;
4385 }
4386 
4387 static const struct seq_operations proto_seq_ops = {
4388 	.start  = proto_seq_start,
4389 	.next   = proto_seq_next,
4390 	.stop   = proto_seq_stop,
4391 	.show   = proto_seq_show,
4392 };
4393 
4394 static __net_init int proto_init_net(struct net *net)
4395 {
4396 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4397 			sizeof(struct seq_net_private)))
4398 		return -ENOMEM;
4399 
4400 	return 0;
4401 }
4402 
4403 static __net_exit void proto_exit_net(struct net *net)
4404 {
4405 	remove_proc_entry("protocols", net->proc_net);
4406 }
4407 
4408 
4409 static __net_initdata struct pernet_operations proto_net_ops = {
4410 	.init = proto_init_net,
4411 	.exit = proto_exit_net,
4412 };
4413 
4414 static int __init proto_init(void)
4415 {
4416 	return register_pernet_subsys(&proto_net_ops);
4417 }
4418 
4419 subsys_initcall(proto_init);
4420 
4421 #endif /* PROC_FS */
4422 
4423 #ifdef CONFIG_NET_RX_BUSY_POLL
4424 bool sk_busy_loop_end(void *p, unsigned long start_time)
4425 {
4426 	struct sock *sk = p;
4427 
4428 	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4429 		return true;
4430 
4431 	if (sk_is_udp(sk) &&
4432 	    !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4433 		return true;
4434 
4435 	return sk_busy_loop_timeout(sk, start_time);
4436 }
4437 EXPORT_SYMBOL(sk_busy_loop_end);
4438 #endif /* CONFIG_NET_RX_BUSY_POLL */
4439 
4440 int sock_bind_add(struct sock *sk, struct sockaddr_unsized *addr, int addr_len)
4441 {
4442 	if (!sk->sk_prot->bind_add)
4443 		return -EOPNOTSUPP;
4444 	return sk->sk_prot->bind_add(sk, addr, addr_len);
4445 }
4446 EXPORT_SYMBOL(sock_bind_add);
4447 
4448 /* Copy 'size' bytes from userspace and return `size` back to userspace */
4449 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4450 		     void __user *arg, void *karg, size_t size)
4451 {
4452 	int ret;
4453 
4454 	if (copy_from_user(karg, arg, size))
4455 		return -EFAULT;
4456 
4457 	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4458 	if (ret)
4459 		return ret;
4460 
4461 	if (copy_to_user(arg, karg, size))
4462 		return -EFAULT;
4463 
4464 	return 0;
4465 }
4466 EXPORT_SYMBOL(sock_ioctl_inout);
4467 
4468 /* This is the most common ioctl prep function, where the result (4 bytes) is
4469  * copied back to userspace if the ioctl() returns successfully. No input is
4470  * copied from userspace as input argument.
4471  */
4472 static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4473 {
4474 	int ret, karg = 0;
4475 
4476 	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4477 	if (ret)
4478 		return ret;
4479 
4480 	return put_user(karg, (int __user *)arg);
4481 }
4482 
4483 /* A wrapper around sock ioctls, which copies the data from userspace
4484  * (depending on the protocol/ioctl), and copies back the result to userspace.
4485  * The main motivation for this function is to pass kernel memory to the
4486  * protocol ioctl callbacks, instead of userspace memory.
4487  */
4488 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4489 {
4490 	int rc = 1;
4491 
4492 	if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4493 		rc = ipmr_sk_ioctl(sk, cmd, arg);
4494 	else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4495 		rc = ip6mr_sk_ioctl(sk, cmd, arg);
4496 	else if (sk_is_phonet(sk))
4497 		rc = phonet_sk_ioctl(sk, cmd, arg);
4498 
4499 	/* If ioctl was processed, returns its value */
4500 	if (rc <= 0)
4501 		return rc;
4502 
4503 	/* Otherwise call the default handler */
4504 	return sock_ioctl_out(sk, cmd, arg);
4505 }
4506 EXPORT_SYMBOL(sk_ioctl);
4507 
4508 static int __init sock_struct_check(void)
4509 {
4510 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_drops);
4511 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_peek_off);
4512 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_error_queue);
4513 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_receive_queue);
4514 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_backlog);
4515 
4516 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst);
4517 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_ifindex);
4518 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_cookie);
4519 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvbuf);
4520 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_filter);
4521 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_wq);
4522 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_data_ready);
4523 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvtimeo);
4524 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvlowat);
4525 
4526 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_err);
4527 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_socket);
4528 #ifdef CONFIG_MEMCG
4529 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_memcg);
4530 #endif
4531 
4532 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_lock);
4533 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_reserved_mem);
4534 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_forward_alloc);
4535 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_tsflags);
4536 
4537 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4538 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4539 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_err_soft);
4540 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_queued);
4541 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_alloc);
4542 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tsq_flags);
4543 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_send_head);
4544 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_queue);
4545 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_pending);
4546 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_frag);
4547 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_timer);
4548 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_rate);
4549 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_zckey);
4550 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tskey);
4551 
4552 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_pending_confirm);
4553 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_status);
4554 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_max_pacing_rate);
4555 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndtimeo);
4556 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_priority);
4557 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_mark);
4558 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_uid);
4559 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_protocol);
4560 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_cache);
4561 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_route_caps);
4562 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_type);
4563 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_size);
4564 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_allocation);
4565 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_txhash);
4566 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndbuf);
4567 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_segs);
4568 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_shift);
4569 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_use_task_frag);
4570 	return 0;
4571 }
4572 
4573 core_initcall(sock_struct_check);
4574