xref: /linux/net/core/sock.c (revision 3186a8e55ae3428ec1e06af09075e20885376e4e)
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 "dev.h"
152 
153 static DEFINE_MUTEX(proto_list_mutex);
154 static LIST_HEAD(proto_list);
155 
156 static void sock_def_write_space_wfree(struct sock *sk);
157 static void sock_def_write_space(struct sock *sk);
158 
159 /**
160  * sk_ns_capable - General socket capability test
161  * @sk: Socket to use a capability on or through
162  * @user_ns: The user namespace of the capability to use
163  * @cap: The capability to use
164  *
165  * Test to see if the opener of the socket had when the socket was
166  * created and the current process has the capability @cap in the user
167  * namespace @user_ns.
168  */
169 bool sk_ns_capable(const struct sock *sk,
170 		   struct user_namespace *user_ns, int cap)
171 {
172 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
173 		ns_capable(user_ns, cap);
174 }
175 EXPORT_SYMBOL(sk_ns_capable);
176 
177 /**
178  * sk_capable - Socket global capability test
179  * @sk: Socket to use a capability on or through
180  * @cap: The global capability to use
181  *
182  * Test to see if the opener of the socket had when the socket was
183  * created and the current process has the capability @cap in all user
184  * namespaces.
185  */
186 bool sk_capable(const struct sock *sk, int cap)
187 {
188 	return sk_ns_capable(sk, &init_user_ns, cap);
189 }
190 EXPORT_SYMBOL(sk_capable);
191 
192 /**
193  * sk_net_capable - Network namespace socket capability test
194  * @sk: Socket to use a capability on or through
195  * @cap: The capability to use
196  *
197  * Test to see if the opener of the socket had when the socket was created
198  * and the current process has the capability @cap over the network namespace
199  * the socket is a member of.
200  */
201 bool sk_net_capable(const struct sock *sk, int cap)
202 {
203 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
204 }
205 EXPORT_SYMBOL(sk_net_capable);
206 
207 /*
208  * Each address family might have different locking rules, so we have
209  * one slock key per address family and separate keys for internal and
210  * userspace sockets.
211  */
212 static struct lock_class_key af_family_keys[AF_MAX];
213 static struct lock_class_key af_family_kern_keys[AF_MAX];
214 static struct lock_class_key af_family_slock_keys[AF_MAX];
215 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
216 
217 /*
218  * Make lock validator output more readable. (we pre-construct these
219  * strings build-time, so that runtime initialization of socket
220  * locks is fast):
221  */
222 
223 #define _sock_locks(x)						  \
224   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
225   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
226   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
227   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
228   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
229   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
230   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
231   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
232   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
233   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
234   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
235   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
236   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
237   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
238   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
239   x "AF_MCTP"  , \
240   x "AF_MAX"
241 
242 static const char *const af_family_key_strings[AF_MAX+1] = {
243 	_sock_locks("sk_lock-")
244 };
245 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
246 	_sock_locks("slock-")
247 };
248 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
249 	_sock_locks("clock-")
250 };
251 
252 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
253 	_sock_locks("k-sk_lock-")
254 };
255 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
256 	_sock_locks("k-slock-")
257 };
258 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
259 	_sock_locks("k-clock-")
260 };
261 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
262 	_sock_locks("rlock-")
263 };
264 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
265 	_sock_locks("wlock-")
266 };
267 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
268 	_sock_locks("elock-")
269 };
270 
271 /*
272  * sk_callback_lock and sk queues locking rules are per-address-family,
273  * so split the lock classes by using a per-AF key:
274  */
275 static struct lock_class_key af_callback_keys[AF_MAX];
276 static struct lock_class_key af_rlock_keys[AF_MAX];
277 static struct lock_class_key af_wlock_keys[AF_MAX];
278 static struct lock_class_key af_elock_keys[AF_MAX];
279 static struct lock_class_key af_kern_callback_keys[AF_MAX];
280 
281 /* Run time adjustable parameters. */
282 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
283 EXPORT_SYMBOL(sysctl_wmem_max);
284 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
285 EXPORT_SYMBOL(sysctl_rmem_max);
286 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
287 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
288 
289 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
290 EXPORT_SYMBOL_GPL(memalloc_socks_key);
291 
292 /**
293  * sk_set_memalloc - sets %SOCK_MEMALLOC
294  * @sk: socket to set it on
295  *
296  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
297  * It's the responsibility of the admin to adjust min_free_kbytes
298  * to meet the requirements
299  */
300 void sk_set_memalloc(struct sock *sk)
301 {
302 	sock_set_flag(sk, SOCK_MEMALLOC);
303 	sk->sk_allocation |= __GFP_MEMALLOC;
304 	static_branch_inc(&memalloc_socks_key);
305 }
306 EXPORT_SYMBOL_GPL(sk_set_memalloc);
307 
308 void sk_clear_memalloc(struct sock *sk)
309 {
310 	sock_reset_flag(sk, SOCK_MEMALLOC);
311 	sk->sk_allocation &= ~__GFP_MEMALLOC;
312 	static_branch_dec(&memalloc_socks_key);
313 
314 	/*
315 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
316 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
317 	 * it has rmem allocations due to the last swapfile being deactivated
318 	 * but there is a risk that the socket is unusable due to exceeding
319 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
320 	 */
321 	sk_mem_reclaim(sk);
322 }
323 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
324 
325 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
326 {
327 	int ret;
328 	unsigned int noreclaim_flag;
329 
330 	/* these should have been dropped before queueing */
331 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
332 
333 	noreclaim_flag = memalloc_noreclaim_save();
334 	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
335 				 tcp_v6_do_rcv,
336 				 tcp_v4_do_rcv,
337 				 sk, skb);
338 	memalloc_noreclaim_restore(noreclaim_flag);
339 
340 	return ret;
341 }
342 EXPORT_SYMBOL(__sk_backlog_rcv);
343 
344 void sk_error_report(struct sock *sk)
345 {
346 	sk->sk_error_report(sk);
347 
348 	switch (sk->sk_family) {
349 	case AF_INET:
350 		fallthrough;
351 	case AF_INET6:
352 		trace_inet_sk_error_report(sk);
353 		break;
354 	default:
355 		break;
356 	}
357 }
358 EXPORT_SYMBOL(sk_error_report);
359 
360 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
361 {
362 	struct __kernel_sock_timeval tv;
363 
364 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
365 		tv.tv_sec = 0;
366 		tv.tv_usec = 0;
367 	} else {
368 		tv.tv_sec = timeo / HZ;
369 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
370 	}
371 
372 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
373 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
374 		*(struct old_timeval32 *)optval = tv32;
375 		return sizeof(tv32);
376 	}
377 
378 	if (old_timeval) {
379 		struct __kernel_old_timeval old_tv;
380 		old_tv.tv_sec = tv.tv_sec;
381 		old_tv.tv_usec = tv.tv_usec;
382 		*(struct __kernel_old_timeval *)optval = old_tv;
383 		return sizeof(old_tv);
384 	}
385 
386 	*(struct __kernel_sock_timeval *)optval = tv;
387 	return sizeof(tv);
388 }
389 EXPORT_SYMBOL(sock_get_timeout);
390 
391 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
392 			   sockptr_t optval, int optlen, bool old_timeval)
393 {
394 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
395 		struct old_timeval32 tv32;
396 
397 		if (optlen < sizeof(tv32))
398 			return -EINVAL;
399 
400 		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
401 			return -EFAULT;
402 		tv->tv_sec = tv32.tv_sec;
403 		tv->tv_usec = tv32.tv_usec;
404 	} else if (old_timeval) {
405 		struct __kernel_old_timeval old_tv;
406 
407 		if (optlen < sizeof(old_tv))
408 			return -EINVAL;
409 		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
410 			return -EFAULT;
411 		tv->tv_sec = old_tv.tv_sec;
412 		tv->tv_usec = old_tv.tv_usec;
413 	} else {
414 		if (optlen < sizeof(*tv))
415 			return -EINVAL;
416 		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
417 			return -EFAULT;
418 	}
419 
420 	return 0;
421 }
422 EXPORT_SYMBOL(sock_copy_user_timeval);
423 
424 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
425 			    bool old_timeval)
426 {
427 	struct __kernel_sock_timeval tv;
428 	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
429 	long val;
430 
431 	if (err)
432 		return err;
433 
434 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
435 		return -EDOM;
436 
437 	if (tv.tv_sec < 0) {
438 		static int warned __read_mostly;
439 
440 		WRITE_ONCE(*timeo_p, 0);
441 		if (warned < 10 && net_ratelimit()) {
442 			warned++;
443 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
444 				__func__, current->comm, task_pid_nr(current));
445 		}
446 		return 0;
447 	}
448 	val = MAX_SCHEDULE_TIMEOUT;
449 	if ((tv.tv_sec || tv.tv_usec) &&
450 	    (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))
451 		val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,
452 						    USEC_PER_SEC / HZ);
453 	WRITE_ONCE(*timeo_p, val);
454 	return 0;
455 }
456 
457 static bool sk_set_prio_allowed(const struct sock *sk, int val)
458 {
459 	return ((val >= TC_PRIO_BESTEFFORT && val <= TC_PRIO_INTERACTIVE) ||
460 		sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
461 		sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN));
462 }
463 
464 static bool sock_needs_netstamp(const struct sock *sk)
465 {
466 	switch (sk->sk_family) {
467 	case AF_UNSPEC:
468 	case AF_UNIX:
469 		return false;
470 	default:
471 		return true;
472 	}
473 }
474 
475 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
476 {
477 	if (sk->sk_flags & flags) {
478 		sk->sk_flags &= ~flags;
479 		if (sock_needs_netstamp(sk) &&
480 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
481 			net_disable_timestamp();
482 	}
483 }
484 
485 
486 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
487 {
488 	unsigned long flags;
489 	struct sk_buff_head *list = &sk->sk_receive_queue;
490 
491 	if (atomic_read(&sk->sk_rmem_alloc) >= READ_ONCE(sk->sk_rcvbuf)) {
492 		atomic_inc(&sk->sk_drops);
493 		trace_sock_rcvqueue_full(sk, skb);
494 		return -ENOMEM;
495 	}
496 
497 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
498 		atomic_inc(&sk->sk_drops);
499 		return -ENOBUFS;
500 	}
501 
502 	skb->dev = NULL;
503 	skb_set_owner_r(skb, sk);
504 
505 	/* we escape from rcu protected region, make sure we dont leak
506 	 * a norefcounted dst
507 	 */
508 	skb_dst_force(skb);
509 
510 	spin_lock_irqsave(&list->lock, flags);
511 	sock_skb_set_dropcount(sk, skb);
512 	__skb_queue_tail(list, skb);
513 	spin_unlock_irqrestore(&list->lock, flags);
514 
515 	if (!sock_flag(sk, SOCK_DEAD))
516 		sk->sk_data_ready(sk);
517 	return 0;
518 }
519 EXPORT_SYMBOL(__sock_queue_rcv_skb);
520 
521 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
522 			      enum skb_drop_reason *reason)
523 {
524 	enum skb_drop_reason drop_reason;
525 	int err;
526 
527 	err = sk_filter(sk, skb);
528 	if (err) {
529 		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
530 		goto out;
531 	}
532 	err = __sock_queue_rcv_skb(sk, skb);
533 	switch (err) {
534 	case -ENOMEM:
535 		drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
536 		break;
537 	case -ENOBUFS:
538 		drop_reason = SKB_DROP_REASON_PROTO_MEM;
539 		break;
540 	default:
541 		drop_reason = SKB_NOT_DROPPED_YET;
542 		break;
543 	}
544 out:
545 	if (reason)
546 		*reason = drop_reason;
547 	return err;
548 }
549 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
550 
551 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
552 		     const int nested, unsigned int trim_cap, bool refcounted)
553 {
554 	int rc = NET_RX_SUCCESS;
555 
556 	if (sk_filter_trim_cap(sk, skb, trim_cap))
557 		goto discard_and_relse;
558 
559 	skb->dev = NULL;
560 
561 	if (sk_rcvqueues_full(sk, READ_ONCE(sk->sk_rcvbuf))) {
562 		atomic_inc(&sk->sk_drops);
563 		goto discard_and_relse;
564 	}
565 	if (nested)
566 		bh_lock_sock_nested(sk);
567 	else
568 		bh_lock_sock(sk);
569 	if (!sock_owned_by_user(sk)) {
570 		/*
571 		 * trylock + unlock semantics:
572 		 */
573 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
574 
575 		rc = sk_backlog_rcv(sk, skb);
576 
577 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
578 	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
579 		bh_unlock_sock(sk);
580 		atomic_inc(&sk->sk_drops);
581 		goto discard_and_relse;
582 	}
583 
584 	bh_unlock_sock(sk);
585 out:
586 	if (refcounted)
587 		sock_put(sk);
588 	return rc;
589 discard_and_relse:
590 	kfree_skb(skb);
591 	goto out;
592 }
593 EXPORT_SYMBOL(__sk_receive_skb);
594 
595 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
596 							  u32));
597 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
598 							   u32));
599 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
600 {
601 	struct dst_entry *dst = __sk_dst_get(sk);
602 
603 	if (dst && dst->obsolete &&
604 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
605 			       dst, cookie) == NULL) {
606 		sk_tx_queue_clear(sk);
607 		WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
608 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
609 		dst_release(dst);
610 		return NULL;
611 	}
612 
613 	return dst;
614 }
615 EXPORT_SYMBOL(__sk_dst_check);
616 
617 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
618 {
619 	struct dst_entry *dst = sk_dst_get(sk);
620 
621 	if (dst && dst->obsolete &&
622 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
623 			       dst, cookie) == NULL) {
624 		sk_dst_reset(sk);
625 		dst_release(dst);
626 		return NULL;
627 	}
628 
629 	return dst;
630 }
631 EXPORT_SYMBOL(sk_dst_check);
632 
633 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
634 {
635 	int ret = -ENOPROTOOPT;
636 #ifdef CONFIG_NETDEVICES
637 	struct net *net = sock_net(sk);
638 
639 	/* Sorry... */
640 	ret = -EPERM;
641 	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
642 		goto out;
643 
644 	ret = -EINVAL;
645 	if (ifindex < 0)
646 		goto out;
647 
648 	/* Paired with all READ_ONCE() done locklessly. */
649 	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
650 
651 	if (sk->sk_prot->rehash)
652 		sk->sk_prot->rehash(sk);
653 	sk_dst_reset(sk);
654 
655 	ret = 0;
656 
657 out:
658 #endif
659 
660 	return ret;
661 }
662 
663 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
664 {
665 	int ret;
666 
667 	if (lock_sk)
668 		lock_sock(sk);
669 	ret = sock_bindtoindex_locked(sk, ifindex);
670 	if (lock_sk)
671 		release_sock(sk);
672 
673 	return ret;
674 }
675 EXPORT_SYMBOL(sock_bindtoindex);
676 
677 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
678 {
679 	int ret = -ENOPROTOOPT;
680 #ifdef CONFIG_NETDEVICES
681 	struct net *net = sock_net(sk);
682 	char devname[IFNAMSIZ];
683 	int index;
684 
685 	ret = -EINVAL;
686 	if (optlen < 0)
687 		goto out;
688 
689 	/* Bind this socket to a particular device like "eth0",
690 	 * as specified in the passed interface name. If the
691 	 * name is "" or the option length is zero the socket
692 	 * is not bound.
693 	 */
694 	if (optlen > IFNAMSIZ - 1)
695 		optlen = IFNAMSIZ - 1;
696 	memset(devname, 0, sizeof(devname));
697 
698 	ret = -EFAULT;
699 	if (copy_from_sockptr(devname, optval, optlen))
700 		goto out;
701 
702 	index = 0;
703 	if (devname[0] != '\0') {
704 		struct net_device *dev;
705 
706 		rcu_read_lock();
707 		dev = dev_get_by_name_rcu(net, devname);
708 		if (dev)
709 			index = dev->ifindex;
710 		rcu_read_unlock();
711 		ret = -ENODEV;
712 		if (!dev)
713 			goto out;
714 	}
715 
716 	sockopt_lock_sock(sk);
717 	ret = sock_bindtoindex_locked(sk, index);
718 	sockopt_release_sock(sk);
719 out:
720 #endif
721 
722 	return ret;
723 }
724 
725 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
726 				sockptr_t optlen, int len)
727 {
728 	int ret = -ENOPROTOOPT;
729 #ifdef CONFIG_NETDEVICES
730 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
731 	struct net *net = sock_net(sk);
732 	char devname[IFNAMSIZ];
733 
734 	if (bound_dev_if == 0) {
735 		len = 0;
736 		goto zero;
737 	}
738 
739 	ret = -EINVAL;
740 	if (len < IFNAMSIZ)
741 		goto out;
742 
743 	ret = netdev_get_name(net, devname, bound_dev_if);
744 	if (ret)
745 		goto out;
746 
747 	len = strlen(devname) + 1;
748 
749 	ret = -EFAULT;
750 	if (copy_to_sockptr(optval, devname, len))
751 		goto out;
752 
753 zero:
754 	ret = -EFAULT;
755 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
756 		goto out;
757 
758 	ret = 0;
759 
760 out:
761 #endif
762 
763 	return ret;
764 }
765 
766 bool sk_mc_loop(const struct sock *sk)
767 {
768 	if (dev_recursion_level())
769 		return false;
770 	if (!sk)
771 		return true;
772 	/* IPV6_ADDRFORM can change sk->sk_family under us. */
773 	switch (READ_ONCE(sk->sk_family)) {
774 	case AF_INET:
775 		return inet_test_bit(MC_LOOP, sk);
776 #if IS_ENABLED(CONFIG_IPV6)
777 	case AF_INET6:
778 		return inet6_test_bit(MC6_LOOP, sk);
779 #endif
780 	}
781 	WARN_ON_ONCE(1);
782 	return true;
783 }
784 EXPORT_SYMBOL(sk_mc_loop);
785 
786 void sock_set_reuseaddr(struct sock *sk)
787 {
788 	lock_sock(sk);
789 	sk->sk_reuse = SK_CAN_REUSE;
790 	release_sock(sk);
791 }
792 EXPORT_SYMBOL(sock_set_reuseaddr);
793 
794 void sock_set_reuseport(struct sock *sk)
795 {
796 	lock_sock(sk);
797 	sk->sk_reuseport = true;
798 	release_sock(sk);
799 }
800 EXPORT_SYMBOL(sock_set_reuseport);
801 
802 void sock_no_linger(struct sock *sk)
803 {
804 	lock_sock(sk);
805 	WRITE_ONCE(sk->sk_lingertime, 0);
806 	sock_set_flag(sk, SOCK_LINGER);
807 	release_sock(sk);
808 }
809 EXPORT_SYMBOL(sock_no_linger);
810 
811 void sock_set_priority(struct sock *sk, u32 priority)
812 {
813 	WRITE_ONCE(sk->sk_priority, priority);
814 }
815 EXPORT_SYMBOL(sock_set_priority);
816 
817 void sock_set_sndtimeo(struct sock *sk, s64 secs)
818 {
819 	lock_sock(sk);
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 	release_sock(sk);
825 }
826 EXPORT_SYMBOL(sock_set_sndtimeo);
827 
828 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
829 {
830 	sock_valbool_flag(sk, SOCK_RCVTSTAMP, val);
831 	sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, val && ns);
832 	if (val)  {
833 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
834 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
835 	}
836 }
837 
838 void sock_enable_timestamps(struct sock *sk)
839 {
840 	lock_sock(sk);
841 	__sock_set_timestamps(sk, true, false, true);
842 	release_sock(sk);
843 }
844 EXPORT_SYMBOL(sock_enable_timestamps);
845 
846 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
847 {
848 	switch (optname) {
849 	case SO_TIMESTAMP_OLD:
850 		__sock_set_timestamps(sk, valbool, false, false);
851 		break;
852 	case SO_TIMESTAMP_NEW:
853 		__sock_set_timestamps(sk, valbool, true, false);
854 		break;
855 	case SO_TIMESTAMPNS_OLD:
856 		__sock_set_timestamps(sk, valbool, false, true);
857 		break;
858 	case SO_TIMESTAMPNS_NEW:
859 		__sock_set_timestamps(sk, valbool, true, true);
860 		break;
861 	}
862 }
863 
864 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
865 {
866 	struct net *net = sock_net(sk);
867 	struct net_device *dev = NULL;
868 	bool match = false;
869 	int *vclock_index;
870 	int i, num;
871 
872 	if (sk->sk_bound_dev_if)
873 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
874 
875 	if (!dev) {
876 		pr_err("%s: sock not bind to device\n", __func__);
877 		return -EOPNOTSUPP;
878 	}
879 
880 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
881 	dev_put(dev);
882 
883 	for (i = 0; i < num; i++) {
884 		if (*(vclock_index + i) == phc_index) {
885 			match = true;
886 			break;
887 		}
888 	}
889 
890 	if (num > 0)
891 		kfree(vclock_index);
892 
893 	if (!match)
894 		return -EINVAL;
895 
896 	WRITE_ONCE(sk->sk_bind_phc, phc_index);
897 
898 	return 0;
899 }
900 
901 int sock_set_timestamping(struct sock *sk, int optname,
902 			  struct so_timestamping timestamping)
903 {
904 	int val = timestamping.flags;
905 	int ret;
906 
907 	if (val & ~SOF_TIMESTAMPING_MASK)
908 		return -EINVAL;
909 
910 	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
911 	    !(val & SOF_TIMESTAMPING_OPT_ID))
912 		return -EINVAL;
913 
914 	if (val & SOF_TIMESTAMPING_OPT_ID &&
915 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
916 		if (sk_is_tcp(sk)) {
917 			if ((1 << sk->sk_state) &
918 			    (TCPF_CLOSE | TCPF_LISTEN))
919 				return -EINVAL;
920 			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
921 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
922 			else
923 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
924 		} else {
925 			atomic_set(&sk->sk_tskey, 0);
926 		}
927 	}
928 
929 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
930 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
931 		return -EINVAL;
932 
933 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
934 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
935 		if (ret)
936 			return ret;
937 	}
938 
939 	WRITE_ONCE(sk->sk_tsflags, val);
940 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
941 	sock_valbool_flag(sk, SOCK_TIMESTAMPING_ANY, !!(val & TSFLAGS_ANY));
942 
943 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
944 		sock_enable_timestamp(sk,
945 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
946 	else
947 		sock_disable_timestamp(sk,
948 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
949 	return 0;
950 }
951 
952 #if defined(CONFIG_CGROUP_BPF)
953 void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op)
954 {
955 	struct bpf_sock_ops_kern sock_ops;
956 
957 	memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp));
958 	sock_ops.op = op;
959 	sock_ops.is_fullsock = 1;
960 	sock_ops.sk = sk;
961 	bpf_skops_init_skb(&sock_ops, skb, 0);
962 	__cgroup_bpf_run_filter_sock_ops(sk, &sock_ops, CGROUP_SOCK_OPS);
963 }
964 #endif
965 
966 void sock_set_keepalive(struct sock *sk)
967 {
968 	lock_sock(sk);
969 	if (sk->sk_prot->keepalive)
970 		sk->sk_prot->keepalive(sk, true);
971 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
972 	release_sock(sk);
973 }
974 EXPORT_SYMBOL(sock_set_keepalive);
975 
976 static void __sock_set_rcvbuf(struct sock *sk, int val)
977 {
978 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
979 	 * as a negative value.
980 	 */
981 	val = min_t(int, val, INT_MAX / 2);
982 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
983 
984 	/* We double it on the way in to account for "struct sk_buff" etc.
985 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
986 	 * will allow that much actual data to be received on that socket.
987 	 *
988 	 * Applications are unaware that "struct sk_buff" and other overheads
989 	 * allocate from the receive buffer during socket buffer allocation.
990 	 *
991 	 * And after considering the possible alternatives, returning the value
992 	 * we actually used in getsockopt is the most desirable behavior.
993 	 */
994 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
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_sockets_enabled || !sk->sk_memcg || !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_charge_skmem(sk->sk_memcg, pages,
1047 					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1048 	if (!charged)
1049 		return -ENOMEM;
1050 
1051 	/* pre-charge to forward_alloc */
1052 	sk_memory_allocated_add(sk, pages);
1053 	allocated = sk_memory_allocated(sk);
1054 	/* If the system goes into memory pressure with this
1055 	 * precharge, give up and return error.
1056 	 */
1057 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1058 		sk_memory_allocated_sub(sk, pages);
1059 		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1060 		return -ENOMEM;
1061 	}
1062 	sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1063 
1064 	WRITE_ONCE(sk->sk_reserved_mem,
1065 		   sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1066 
1067 	return 0;
1068 }
1069 
1070 #ifdef CONFIG_PAGE_POOL
1071 
1072 /* This is the number of tokens and frags that the user can SO_DEVMEM_DONTNEED
1073  * in 1 syscall. The limit exists to limit the amount of memory the kernel
1074  * allocates to copy these tokens, and to prevent looping over the frags for
1075  * too long.
1076  */
1077 #define MAX_DONTNEED_TOKENS 128
1078 #define MAX_DONTNEED_FRAGS 1024
1079 
1080 static noinline_for_stack int
1081 sock_devmem_dontneed(struct sock *sk, sockptr_t optval, unsigned int optlen)
1082 {
1083 	unsigned int num_tokens, i, j, k, netmem_num = 0;
1084 	struct dmabuf_token *tokens;
1085 	int ret = 0, num_frags = 0;
1086 	netmem_ref netmems[16];
1087 
1088 	if (!sk_is_tcp(sk))
1089 		return -EBADF;
1090 
1091 	if (optlen % sizeof(*tokens) ||
1092 	    optlen > sizeof(*tokens) * MAX_DONTNEED_TOKENS)
1093 		return -EINVAL;
1094 
1095 	num_tokens = optlen / sizeof(*tokens);
1096 	tokens = kvmalloc_array(num_tokens, sizeof(*tokens), GFP_KERNEL);
1097 	if (!tokens)
1098 		return -ENOMEM;
1099 
1100 	if (copy_from_sockptr(tokens, optval, optlen)) {
1101 		kvfree(tokens);
1102 		return -EFAULT;
1103 	}
1104 
1105 	xa_lock_bh(&sk->sk_user_frags);
1106 	for (i = 0; i < num_tokens; i++) {
1107 		for (j = 0; j < tokens[i].token_count; j++) {
1108 			if (++num_frags > MAX_DONTNEED_FRAGS)
1109 				goto frag_limit_reached;
1110 
1111 			netmem_ref netmem = (__force netmem_ref)__xa_erase(
1112 				&sk->sk_user_frags, tokens[i].token_start + j);
1113 
1114 			if (!netmem || WARN_ON_ONCE(!netmem_is_net_iov(netmem)))
1115 				continue;
1116 
1117 			netmems[netmem_num++] = netmem;
1118 			if (netmem_num == ARRAY_SIZE(netmems)) {
1119 				xa_unlock_bh(&sk->sk_user_frags);
1120 				for (k = 0; k < netmem_num; k++)
1121 					WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1122 				netmem_num = 0;
1123 				xa_lock_bh(&sk->sk_user_frags);
1124 			}
1125 			ret++;
1126 		}
1127 	}
1128 
1129 frag_limit_reached:
1130 	xa_unlock_bh(&sk->sk_user_frags);
1131 	for (k = 0; k < netmem_num; k++)
1132 		WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1133 
1134 	kvfree(tokens);
1135 	return ret;
1136 }
1137 #endif
1138 
1139 void sockopt_lock_sock(struct sock *sk)
1140 {
1141 	/* When current->bpf_ctx is set, the setsockopt is called from
1142 	 * a bpf prog.  bpf has ensured the sk lock has been
1143 	 * acquired before calling setsockopt().
1144 	 */
1145 	if (has_current_bpf_ctx())
1146 		return;
1147 
1148 	lock_sock(sk);
1149 }
1150 EXPORT_SYMBOL(sockopt_lock_sock);
1151 
1152 void sockopt_release_sock(struct sock *sk)
1153 {
1154 	if (has_current_bpf_ctx())
1155 		return;
1156 
1157 	release_sock(sk);
1158 }
1159 EXPORT_SYMBOL(sockopt_release_sock);
1160 
1161 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1162 {
1163 	return has_current_bpf_ctx() || ns_capable(ns, cap);
1164 }
1165 EXPORT_SYMBOL(sockopt_ns_capable);
1166 
1167 bool sockopt_capable(int cap)
1168 {
1169 	return has_current_bpf_ctx() || capable(cap);
1170 }
1171 EXPORT_SYMBOL(sockopt_capable);
1172 
1173 static int sockopt_validate_clockid(__kernel_clockid_t value)
1174 {
1175 	switch (value) {
1176 	case CLOCK_REALTIME:
1177 	case CLOCK_MONOTONIC:
1178 	case CLOCK_TAI:
1179 		return 0;
1180 	}
1181 	return -EINVAL;
1182 }
1183 
1184 /*
1185  *	This is meant for all protocols to use and covers goings on
1186  *	at the socket level. Everything here is generic.
1187  */
1188 
1189 int sk_setsockopt(struct sock *sk, int level, int optname,
1190 		  sockptr_t optval, unsigned int optlen)
1191 {
1192 	struct so_timestamping timestamping;
1193 	struct socket *sock = sk->sk_socket;
1194 	struct sock_txtime sk_txtime;
1195 	int val;
1196 	int valbool;
1197 	struct linger ling;
1198 	int ret = 0;
1199 
1200 	/*
1201 	 *	Options without arguments
1202 	 */
1203 
1204 	if (optname == SO_BINDTODEVICE)
1205 		return sock_setbindtodevice(sk, optval, optlen);
1206 
1207 	if (optlen < sizeof(int))
1208 		return -EINVAL;
1209 
1210 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1211 		return -EFAULT;
1212 
1213 	valbool = val ? 1 : 0;
1214 
1215 	/* handle options which do not require locking the socket. */
1216 	switch (optname) {
1217 	case SO_PRIORITY:
1218 		if (sk_set_prio_allowed(sk, val)) {
1219 			sock_set_priority(sk, val);
1220 			return 0;
1221 		}
1222 		return -EPERM;
1223 	case SO_PASSSEC:
1224 		assign_bit(SOCK_PASSSEC, &sock->flags, valbool);
1225 		return 0;
1226 	case SO_PASSCRED:
1227 		assign_bit(SOCK_PASSCRED, &sock->flags, valbool);
1228 		return 0;
1229 	case SO_PASSPIDFD:
1230 		assign_bit(SOCK_PASSPIDFD, &sock->flags, valbool);
1231 		return 0;
1232 	case SO_TYPE:
1233 	case SO_PROTOCOL:
1234 	case SO_DOMAIN:
1235 	case SO_ERROR:
1236 		return -ENOPROTOOPT;
1237 #ifdef CONFIG_NET_RX_BUSY_POLL
1238 	case SO_BUSY_POLL:
1239 		if (val < 0)
1240 			return -EINVAL;
1241 		WRITE_ONCE(sk->sk_ll_usec, val);
1242 		return 0;
1243 	case SO_PREFER_BUSY_POLL:
1244 		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1245 			return -EPERM;
1246 		WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1247 		return 0;
1248 	case SO_BUSY_POLL_BUDGET:
1249 		if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1250 		    !sockopt_capable(CAP_NET_ADMIN))
1251 			return -EPERM;
1252 		if (val < 0 || val > U16_MAX)
1253 			return -EINVAL;
1254 		WRITE_ONCE(sk->sk_busy_poll_budget, val);
1255 		return 0;
1256 #endif
1257 	case SO_MAX_PACING_RATE:
1258 		{
1259 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1260 		unsigned long pacing_rate;
1261 
1262 		if (sizeof(ulval) != sizeof(val) &&
1263 		    optlen >= sizeof(ulval) &&
1264 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1265 			return -EFAULT;
1266 		}
1267 		if (ulval != ~0UL)
1268 			cmpxchg(&sk->sk_pacing_status,
1269 				SK_PACING_NONE,
1270 				SK_PACING_NEEDED);
1271 		/* Pairs with READ_ONCE() from sk_getsockopt() */
1272 		WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1273 		pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1274 		if (ulval < pacing_rate)
1275 			WRITE_ONCE(sk->sk_pacing_rate, ulval);
1276 		return 0;
1277 		}
1278 	case SO_TXREHASH:
1279 		if (val < -1 || val > 1)
1280 			return -EINVAL;
1281 		if ((u8)val == SOCK_TXREHASH_DEFAULT)
1282 			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1283 		/* Paired with READ_ONCE() in tcp_rtx_synack()
1284 		 * and sk_getsockopt().
1285 		 */
1286 		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1287 		return 0;
1288 	case SO_PEEK_OFF:
1289 		{
1290 		int (*set_peek_off)(struct sock *sk, int val);
1291 
1292 		set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1293 		if (set_peek_off)
1294 			ret = set_peek_off(sk, val);
1295 		else
1296 			ret = -EOPNOTSUPP;
1297 		return ret;
1298 		}
1299 #ifdef CONFIG_PAGE_POOL
1300 	case SO_DEVMEM_DONTNEED:
1301 		return sock_devmem_dontneed(sk, optval, optlen);
1302 #endif
1303 	}
1304 
1305 	sockopt_lock_sock(sk);
1306 
1307 	switch (optname) {
1308 	case SO_DEBUG:
1309 		if (val && !sockopt_capable(CAP_NET_ADMIN))
1310 			ret = -EACCES;
1311 		else
1312 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1313 		break;
1314 	case SO_REUSEADDR:
1315 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1316 		break;
1317 	case SO_REUSEPORT:
1318 		if (valbool && !sk_is_inet(sk))
1319 			ret = -EOPNOTSUPP;
1320 		else
1321 			sk->sk_reuseport = valbool;
1322 		break;
1323 	case SO_DONTROUTE:
1324 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1325 		sk_dst_reset(sk);
1326 		break;
1327 	case SO_BROADCAST:
1328 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1329 		break;
1330 	case SO_SNDBUF:
1331 		/* Don't error on this BSD doesn't and if you think
1332 		 * about it this is right. Otherwise apps have to
1333 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1334 		 * are treated in BSD as hints
1335 		 */
1336 		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1337 set_sndbuf:
1338 		/* Ensure val * 2 fits into an int, to prevent max_t()
1339 		 * from treating it as a negative value.
1340 		 */
1341 		val = min_t(int, val, INT_MAX / 2);
1342 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1343 		WRITE_ONCE(sk->sk_sndbuf,
1344 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1345 		/* Wake up sending tasks if we upped the value. */
1346 		sk->sk_write_space(sk);
1347 		break;
1348 
1349 	case SO_SNDBUFFORCE:
1350 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1351 			ret = -EPERM;
1352 			break;
1353 		}
1354 
1355 		/* No negative values (to prevent underflow, as val will be
1356 		 * multiplied by 2).
1357 		 */
1358 		if (val < 0)
1359 			val = 0;
1360 		goto set_sndbuf;
1361 
1362 	case SO_RCVBUF:
1363 		/* Don't error on this BSD doesn't and if you think
1364 		 * about it this is right. Otherwise apps have to
1365 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1366 		 * are treated in BSD as hints
1367 		 */
1368 		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1369 		break;
1370 
1371 	case SO_RCVBUFFORCE:
1372 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1373 			ret = -EPERM;
1374 			break;
1375 		}
1376 
1377 		/* No negative values (to prevent underflow, as val will be
1378 		 * multiplied by 2).
1379 		 */
1380 		__sock_set_rcvbuf(sk, max(val, 0));
1381 		break;
1382 
1383 	case SO_KEEPALIVE:
1384 		if (sk->sk_prot->keepalive)
1385 			sk->sk_prot->keepalive(sk, valbool);
1386 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1387 		break;
1388 
1389 	case SO_OOBINLINE:
1390 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1391 		break;
1392 
1393 	case SO_NO_CHECK:
1394 		sk->sk_no_check_tx = valbool;
1395 		break;
1396 
1397 	case SO_LINGER:
1398 		if (optlen < sizeof(ling)) {
1399 			ret = -EINVAL;	/* 1003.1g */
1400 			break;
1401 		}
1402 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1403 			ret = -EFAULT;
1404 			break;
1405 		}
1406 		if (!ling.l_onoff) {
1407 			sock_reset_flag(sk, SOCK_LINGER);
1408 		} else {
1409 			unsigned long t_sec = ling.l_linger;
1410 
1411 			if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1412 				WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1413 			else
1414 				WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
1415 			sock_set_flag(sk, SOCK_LINGER);
1416 		}
1417 		break;
1418 
1419 	case SO_BSDCOMPAT:
1420 		break;
1421 
1422 	case SO_TIMESTAMP_OLD:
1423 	case SO_TIMESTAMP_NEW:
1424 	case SO_TIMESTAMPNS_OLD:
1425 	case SO_TIMESTAMPNS_NEW:
1426 		sock_set_timestamp(sk, optname, valbool);
1427 		break;
1428 
1429 	case SO_TIMESTAMPING_NEW:
1430 	case SO_TIMESTAMPING_OLD:
1431 		if (optlen == sizeof(timestamping)) {
1432 			if (copy_from_sockptr(&timestamping, optval,
1433 					      sizeof(timestamping))) {
1434 				ret = -EFAULT;
1435 				break;
1436 			}
1437 		} else {
1438 			memset(&timestamping, 0, sizeof(timestamping));
1439 			timestamping.flags = val;
1440 		}
1441 		ret = sock_set_timestamping(sk, optname, timestamping);
1442 		break;
1443 
1444 	case SO_RCVLOWAT:
1445 		{
1446 		int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
1447 
1448 		if (val < 0)
1449 			val = INT_MAX;
1450 		if (sock)
1451 			set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1452 		if (set_rcvlowat)
1453 			ret = set_rcvlowat(sk, val);
1454 		else
1455 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1456 		break;
1457 		}
1458 	case SO_RCVTIMEO_OLD:
1459 	case SO_RCVTIMEO_NEW:
1460 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1461 				       optlen, optname == SO_RCVTIMEO_OLD);
1462 		break;
1463 
1464 	case SO_SNDTIMEO_OLD:
1465 	case SO_SNDTIMEO_NEW:
1466 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1467 				       optlen, optname == SO_SNDTIMEO_OLD);
1468 		break;
1469 
1470 	case SO_ATTACH_FILTER: {
1471 		struct sock_fprog fprog;
1472 
1473 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1474 		if (!ret)
1475 			ret = sk_attach_filter(&fprog, sk);
1476 		break;
1477 	}
1478 	case SO_ATTACH_BPF:
1479 		ret = -EINVAL;
1480 		if (optlen == sizeof(u32)) {
1481 			u32 ufd;
1482 
1483 			ret = -EFAULT;
1484 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1485 				break;
1486 
1487 			ret = sk_attach_bpf(ufd, sk);
1488 		}
1489 		break;
1490 
1491 	case SO_ATTACH_REUSEPORT_CBPF: {
1492 		struct sock_fprog fprog;
1493 
1494 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1495 		if (!ret)
1496 			ret = sk_reuseport_attach_filter(&fprog, sk);
1497 		break;
1498 	}
1499 	case SO_ATTACH_REUSEPORT_EBPF:
1500 		ret = -EINVAL;
1501 		if (optlen == sizeof(u32)) {
1502 			u32 ufd;
1503 
1504 			ret = -EFAULT;
1505 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1506 				break;
1507 
1508 			ret = sk_reuseport_attach_bpf(ufd, sk);
1509 		}
1510 		break;
1511 
1512 	case SO_DETACH_REUSEPORT_BPF:
1513 		ret = reuseport_detach_prog(sk);
1514 		break;
1515 
1516 	case SO_DETACH_FILTER:
1517 		ret = sk_detach_filter(sk);
1518 		break;
1519 
1520 	case SO_LOCK_FILTER:
1521 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1522 			ret = -EPERM;
1523 		else
1524 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1525 		break;
1526 
1527 	case SO_MARK:
1528 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1529 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1530 			ret = -EPERM;
1531 			break;
1532 		}
1533 
1534 		__sock_set_mark(sk, val);
1535 		break;
1536 	case SO_RCVMARK:
1537 		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1538 		break;
1539 
1540 	case SO_RCVPRIORITY:
1541 		sock_valbool_flag(sk, SOCK_RCVPRIORITY, valbool);
1542 		break;
1543 
1544 	case SO_RXQ_OVFL:
1545 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1546 		break;
1547 
1548 	case SO_WIFI_STATUS:
1549 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1550 		break;
1551 
1552 	case SO_NOFCS:
1553 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1554 		break;
1555 
1556 	case SO_SELECT_ERR_QUEUE:
1557 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1558 		break;
1559 
1560 
1561 	case SO_INCOMING_CPU:
1562 		reuseport_update_incoming_cpu(sk, val);
1563 		break;
1564 
1565 	case SO_CNX_ADVICE:
1566 		if (val == 1)
1567 			dst_negative_advice(sk);
1568 		break;
1569 
1570 	case SO_ZEROCOPY:
1571 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1572 			if (!(sk_is_tcp(sk) ||
1573 			      (sk->sk_type == SOCK_DGRAM &&
1574 			       sk->sk_protocol == IPPROTO_UDP)))
1575 				ret = -EOPNOTSUPP;
1576 		} else if (sk->sk_family != PF_RDS) {
1577 			ret = -EOPNOTSUPP;
1578 		}
1579 		if (!ret) {
1580 			if (val < 0 || val > 1)
1581 				ret = -EINVAL;
1582 			else
1583 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1584 		}
1585 		break;
1586 
1587 	case SO_TXTIME:
1588 		if (optlen != sizeof(struct sock_txtime)) {
1589 			ret = -EINVAL;
1590 			break;
1591 		} else if (copy_from_sockptr(&sk_txtime, optval,
1592 			   sizeof(struct sock_txtime))) {
1593 			ret = -EFAULT;
1594 			break;
1595 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1596 			ret = -EINVAL;
1597 			break;
1598 		}
1599 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1600 		 * scheduler has enough safe guards.
1601 		 */
1602 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1603 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1604 			ret = -EPERM;
1605 			break;
1606 		}
1607 
1608 		ret = sockopt_validate_clockid(sk_txtime.clockid);
1609 		if (ret)
1610 			break;
1611 
1612 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1613 		sk->sk_clockid = sk_txtime.clockid;
1614 		sk->sk_txtime_deadline_mode =
1615 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1616 		sk->sk_txtime_report_errors =
1617 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1618 		break;
1619 
1620 	case SO_BINDTOIFINDEX:
1621 		ret = sock_bindtoindex_locked(sk, val);
1622 		break;
1623 
1624 	case SO_BUF_LOCK:
1625 		if (val & ~SOCK_BUF_LOCK_MASK) {
1626 			ret = -EINVAL;
1627 			break;
1628 		}
1629 		sk->sk_userlocks = val | (sk->sk_userlocks &
1630 					  ~SOCK_BUF_LOCK_MASK);
1631 		break;
1632 
1633 	case SO_RESERVE_MEM:
1634 	{
1635 		int delta;
1636 
1637 		if (val < 0) {
1638 			ret = -EINVAL;
1639 			break;
1640 		}
1641 
1642 		delta = val - sk->sk_reserved_mem;
1643 		if (delta < 0)
1644 			sock_release_reserved_memory(sk, -delta);
1645 		else
1646 			ret = sock_reserve_memory(sk, delta);
1647 		break;
1648 	}
1649 
1650 	default:
1651 		ret = -ENOPROTOOPT;
1652 		break;
1653 	}
1654 	sockopt_release_sock(sk);
1655 	return ret;
1656 }
1657 
1658 int sock_setsockopt(struct socket *sock, int level, int optname,
1659 		    sockptr_t optval, unsigned int optlen)
1660 {
1661 	return sk_setsockopt(sock->sk, level, optname,
1662 			     optval, optlen);
1663 }
1664 EXPORT_SYMBOL(sock_setsockopt);
1665 
1666 static const struct cred *sk_get_peer_cred(struct sock *sk)
1667 {
1668 	const struct cred *cred;
1669 
1670 	spin_lock(&sk->sk_peer_lock);
1671 	cred = get_cred(sk->sk_peer_cred);
1672 	spin_unlock(&sk->sk_peer_lock);
1673 
1674 	return cred;
1675 }
1676 
1677 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1678 			  struct ucred *ucred)
1679 {
1680 	ucred->pid = pid_vnr(pid);
1681 	ucred->uid = ucred->gid = -1;
1682 	if (cred) {
1683 		struct user_namespace *current_ns = current_user_ns();
1684 
1685 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1686 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1687 	}
1688 }
1689 
1690 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1691 {
1692 	struct user_namespace *user_ns = current_user_ns();
1693 	int i;
1694 
1695 	for (i = 0; i < src->ngroups; i++) {
1696 		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1697 
1698 		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1699 			return -EFAULT;
1700 	}
1701 
1702 	return 0;
1703 }
1704 
1705 int sk_getsockopt(struct sock *sk, int level, int optname,
1706 		  sockptr_t optval, sockptr_t optlen)
1707 {
1708 	struct socket *sock = sk->sk_socket;
1709 
1710 	union {
1711 		int val;
1712 		u64 val64;
1713 		unsigned long ulval;
1714 		struct linger ling;
1715 		struct old_timeval32 tm32;
1716 		struct __kernel_old_timeval tm;
1717 		struct  __kernel_sock_timeval stm;
1718 		struct sock_txtime txtime;
1719 		struct so_timestamping timestamping;
1720 	} v;
1721 
1722 	int lv = sizeof(int);
1723 	int len;
1724 
1725 	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1726 		return -EFAULT;
1727 	if (len < 0)
1728 		return -EINVAL;
1729 
1730 	memset(&v, 0, sizeof(v));
1731 
1732 	switch (optname) {
1733 	case SO_DEBUG:
1734 		v.val = sock_flag(sk, SOCK_DBG);
1735 		break;
1736 
1737 	case SO_DONTROUTE:
1738 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1739 		break;
1740 
1741 	case SO_BROADCAST:
1742 		v.val = sock_flag(sk, SOCK_BROADCAST);
1743 		break;
1744 
1745 	case SO_SNDBUF:
1746 		v.val = READ_ONCE(sk->sk_sndbuf);
1747 		break;
1748 
1749 	case SO_RCVBUF:
1750 		v.val = READ_ONCE(sk->sk_rcvbuf);
1751 		break;
1752 
1753 	case SO_REUSEADDR:
1754 		v.val = sk->sk_reuse;
1755 		break;
1756 
1757 	case SO_REUSEPORT:
1758 		v.val = sk->sk_reuseport;
1759 		break;
1760 
1761 	case SO_KEEPALIVE:
1762 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1763 		break;
1764 
1765 	case SO_TYPE:
1766 		v.val = sk->sk_type;
1767 		break;
1768 
1769 	case SO_PROTOCOL:
1770 		v.val = sk->sk_protocol;
1771 		break;
1772 
1773 	case SO_DOMAIN:
1774 		v.val = sk->sk_family;
1775 		break;
1776 
1777 	case SO_ERROR:
1778 		v.val = -sock_error(sk);
1779 		if (v.val == 0)
1780 			v.val = xchg(&sk->sk_err_soft, 0);
1781 		break;
1782 
1783 	case SO_OOBINLINE:
1784 		v.val = sock_flag(sk, SOCK_URGINLINE);
1785 		break;
1786 
1787 	case SO_NO_CHECK:
1788 		v.val = sk->sk_no_check_tx;
1789 		break;
1790 
1791 	case SO_PRIORITY:
1792 		v.val = READ_ONCE(sk->sk_priority);
1793 		break;
1794 
1795 	case SO_LINGER:
1796 		lv		= sizeof(v.ling);
1797 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1798 		v.ling.l_linger	= READ_ONCE(sk->sk_lingertime) / HZ;
1799 		break;
1800 
1801 	case SO_BSDCOMPAT:
1802 		break;
1803 
1804 	case SO_TIMESTAMP_OLD:
1805 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1806 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1807 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1808 		break;
1809 
1810 	case SO_TIMESTAMPNS_OLD:
1811 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1812 		break;
1813 
1814 	case SO_TIMESTAMP_NEW:
1815 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1816 		break;
1817 
1818 	case SO_TIMESTAMPNS_NEW:
1819 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1820 		break;
1821 
1822 	case SO_TIMESTAMPING_OLD:
1823 	case SO_TIMESTAMPING_NEW:
1824 		lv = sizeof(v.timestamping);
1825 		/* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1826 		 * returning the flags when they were set through the same option.
1827 		 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1828 		 */
1829 		if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1830 			v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1831 			v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1832 		}
1833 		break;
1834 
1835 	case SO_RCVTIMEO_OLD:
1836 	case SO_RCVTIMEO_NEW:
1837 		lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1838 				      SO_RCVTIMEO_OLD == optname);
1839 		break;
1840 
1841 	case SO_SNDTIMEO_OLD:
1842 	case SO_SNDTIMEO_NEW:
1843 		lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1844 				      SO_SNDTIMEO_OLD == optname);
1845 		break;
1846 
1847 	case SO_RCVLOWAT:
1848 		v.val = READ_ONCE(sk->sk_rcvlowat);
1849 		break;
1850 
1851 	case SO_SNDLOWAT:
1852 		v.val = 1;
1853 		break;
1854 
1855 	case SO_PASSCRED:
1856 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1857 		break;
1858 
1859 	case SO_PASSPIDFD:
1860 		v.val = !!test_bit(SOCK_PASSPIDFD, &sock->flags);
1861 		break;
1862 
1863 	case SO_PEERCRED:
1864 	{
1865 		struct ucred peercred;
1866 		if (len > sizeof(peercred))
1867 			len = sizeof(peercred);
1868 
1869 		spin_lock(&sk->sk_peer_lock);
1870 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1871 		spin_unlock(&sk->sk_peer_lock);
1872 
1873 		if (copy_to_sockptr(optval, &peercred, len))
1874 			return -EFAULT;
1875 		goto lenout;
1876 	}
1877 
1878 	case SO_PEERPIDFD:
1879 	{
1880 		struct pid *peer_pid;
1881 		struct file *pidfd_file = NULL;
1882 		int pidfd;
1883 
1884 		if (len > sizeof(pidfd))
1885 			len = sizeof(pidfd);
1886 
1887 		spin_lock(&sk->sk_peer_lock);
1888 		peer_pid = get_pid(sk->sk_peer_pid);
1889 		spin_unlock(&sk->sk_peer_lock);
1890 
1891 		if (!peer_pid)
1892 			return -ENODATA;
1893 
1894 		pidfd = pidfd_prepare(peer_pid, 0, &pidfd_file);
1895 		put_pid(peer_pid);
1896 		if (pidfd < 0)
1897 			return pidfd;
1898 
1899 		if (copy_to_sockptr(optval, &pidfd, len) ||
1900 		    copy_to_sockptr(optlen, &len, sizeof(int))) {
1901 			put_unused_fd(pidfd);
1902 			fput(pidfd_file);
1903 
1904 			return -EFAULT;
1905 		}
1906 
1907 		fd_install(pidfd, pidfd_file);
1908 		return 0;
1909 	}
1910 
1911 	case SO_PEERGROUPS:
1912 	{
1913 		const struct cred *cred;
1914 		int ret, n;
1915 
1916 		cred = sk_get_peer_cred(sk);
1917 		if (!cred)
1918 			return -ENODATA;
1919 
1920 		n = cred->group_info->ngroups;
1921 		if (len < n * sizeof(gid_t)) {
1922 			len = n * sizeof(gid_t);
1923 			put_cred(cred);
1924 			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1925 		}
1926 		len = n * sizeof(gid_t);
1927 
1928 		ret = groups_to_user(optval, cred->group_info);
1929 		put_cred(cred);
1930 		if (ret)
1931 			return ret;
1932 		goto lenout;
1933 	}
1934 
1935 	case SO_PEERNAME:
1936 	{
1937 		struct sockaddr_storage address;
1938 
1939 		lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1940 		if (lv < 0)
1941 			return -ENOTCONN;
1942 		if (lv < len)
1943 			return -EINVAL;
1944 		if (copy_to_sockptr(optval, &address, len))
1945 			return -EFAULT;
1946 		goto lenout;
1947 	}
1948 
1949 	/* Dubious BSD thing... Probably nobody even uses it, but
1950 	 * the UNIX standard wants it for whatever reason... -DaveM
1951 	 */
1952 	case SO_ACCEPTCONN:
1953 		v.val = sk->sk_state == TCP_LISTEN;
1954 		break;
1955 
1956 	case SO_PASSSEC:
1957 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1958 		break;
1959 
1960 	case SO_PEERSEC:
1961 		return security_socket_getpeersec_stream(sock,
1962 							 optval, optlen, len);
1963 
1964 	case SO_MARK:
1965 		v.val = READ_ONCE(sk->sk_mark);
1966 		break;
1967 
1968 	case SO_RCVMARK:
1969 		v.val = sock_flag(sk, SOCK_RCVMARK);
1970 		break;
1971 
1972 	case SO_RCVPRIORITY:
1973 		v.val = sock_flag(sk, SOCK_RCVPRIORITY);
1974 		break;
1975 
1976 	case SO_RXQ_OVFL:
1977 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1978 		break;
1979 
1980 	case SO_WIFI_STATUS:
1981 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1982 		break;
1983 
1984 	case SO_PEEK_OFF:
1985 		if (!READ_ONCE(sock->ops)->set_peek_off)
1986 			return -EOPNOTSUPP;
1987 
1988 		v.val = READ_ONCE(sk->sk_peek_off);
1989 		break;
1990 	case SO_NOFCS:
1991 		v.val = sock_flag(sk, SOCK_NOFCS);
1992 		break;
1993 
1994 	case SO_BINDTODEVICE:
1995 		return sock_getbindtodevice(sk, optval, optlen, len);
1996 
1997 	case SO_GET_FILTER:
1998 		len = sk_get_filter(sk, optval, len);
1999 		if (len < 0)
2000 			return len;
2001 
2002 		goto lenout;
2003 
2004 	case SO_LOCK_FILTER:
2005 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
2006 		break;
2007 
2008 	case SO_BPF_EXTENSIONS:
2009 		v.val = bpf_tell_extensions();
2010 		break;
2011 
2012 	case SO_SELECT_ERR_QUEUE:
2013 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
2014 		break;
2015 
2016 #ifdef CONFIG_NET_RX_BUSY_POLL
2017 	case SO_BUSY_POLL:
2018 		v.val = READ_ONCE(sk->sk_ll_usec);
2019 		break;
2020 	case SO_PREFER_BUSY_POLL:
2021 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
2022 		break;
2023 #endif
2024 
2025 	case SO_MAX_PACING_RATE:
2026 		/* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
2027 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
2028 			lv = sizeof(v.ulval);
2029 			v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
2030 		} else {
2031 			/* 32bit version */
2032 			v.val = min_t(unsigned long, ~0U,
2033 				      READ_ONCE(sk->sk_max_pacing_rate));
2034 		}
2035 		break;
2036 
2037 	case SO_INCOMING_CPU:
2038 		v.val = READ_ONCE(sk->sk_incoming_cpu);
2039 		break;
2040 
2041 	case SO_MEMINFO:
2042 	{
2043 		u32 meminfo[SK_MEMINFO_VARS];
2044 
2045 		sk_get_meminfo(sk, meminfo);
2046 
2047 		len = min_t(unsigned int, len, sizeof(meminfo));
2048 		if (copy_to_sockptr(optval, &meminfo, len))
2049 			return -EFAULT;
2050 
2051 		goto lenout;
2052 	}
2053 
2054 #ifdef CONFIG_NET_RX_BUSY_POLL
2055 	case SO_INCOMING_NAPI_ID:
2056 		v.val = READ_ONCE(sk->sk_napi_id);
2057 
2058 		/* aggregate non-NAPI IDs down to 0 */
2059 		if (!napi_id_valid(v.val))
2060 			v.val = 0;
2061 
2062 		break;
2063 #endif
2064 
2065 	case SO_COOKIE:
2066 		lv = sizeof(u64);
2067 		if (len < lv)
2068 			return -EINVAL;
2069 		v.val64 = sock_gen_cookie(sk);
2070 		break;
2071 
2072 	case SO_ZEROCOPY:
2073 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
2074 		break;
2075 
2076 	case SO_TXTIME:
2077 		lv = sizeof(v.txtime);
2078 		v.txtime.clockid = sk->sk_clockid;
2079 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
2080 				  SOF_TXTIME_DEADLINE_MODE : 0;
2081 		v.txtime.flags |= sk->sk_txtime_report_errors ?
2082 				  SOF_TXTIME_REPORT_ERRORS : 0;
2083 		break;
2084 
2085 	case SO_BINDTOIFINDEX:
2086 		v.val = READ_ONCE(sk->sk_bound_dev_if);
2087 		break;
2088 
2089 	case SO_NETNS_COOKIE:
2090 		lv = sizeof(u64);
2091 		if (len != lv)
2092 			return -EINVAL;
2093 		v.val64 = sock_net(sk)->net_cookie;
2094 		break;
2095 
2096 	case SO_BUF_LOCK:
2097 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
2098 		break;
2099 
2100 	case SO_RESERVE_MEM:
2101 		v.val = READ_ONCE(sk->sk_reserved_mem);
2102 		break;
2103 
2104 	case SO_TXREHASH:
2105 		/* Paired with WRITE_ONCE() in sk_setsockopt() */
2106 		v.val = READ_ONCE(sk->sk_txrehash);
2107 		break;
2108 
2109 	default:
2110 		/* We implement the SO_SNDLOWAT etc to not be settable
2111 		 * (1003.1g 7).
2112 		 */
2113 		return -ENOPROTOOPT;
2114 	}
2115 
2116 	if (len > lv)
2117 		len = lv;
2118 	if (copy_to_sockptr(optval, &v, len))
2119 		return -EFAULT;
2120 lenout:
2121 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
2122 		return -EFAULT;
2123 	return 0;
2124 }
2125 
2126 /*
2127  * Initialize an sk_lock.
2128  *
2129  * (We also register the sk_lock with the lock validator.)
2130  */
2131 static inline void sock_lock_init(struct sock *sk)
2132 {
2133 	sk_owner_clear(sk);
2134 
2135 	if (sk->sk_kern_sock)
2136 		sock_lock_init_class_and_name(
2137 			sk,
2138 			af_family_kern_slock_key_strings[sk->sk_family],
2139 			af_family_kern_slock_keys + sk->sk_family,
2140 			af_family_kern_key_strings[sk->sk_family],
2141 			af_family_kern_keys + sk->sk_family);
2142 	else
2143 		sock_lock_init_class_and_name(
2144 			sk,
2145 			af_family_slock_key_strings[sk->sk_family],
2146 			af_family_slock_keys + sk->sk_family,
2147 			af_family_key_strings[sk->sk_family],
2148 			af_family_keys + sk->sk_family);
2149 }
2150 
2151 /*
2152  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2153  * even temporarily, because of RCU lookups. sk_node should also be left as is.
2154  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2155  */
2156 static void sock_copy(struct sock *nsk, const struct sock *osk)
2157 {
2158 	const struct proto *prot = READ_ONCE(osk->sk_prot);
2159 #ifdef CONFIG_SECURITY_NETWORK
2160 	void *sptr = nsk->sk_security;
2161 #endif
2162 
2163 	/* If we move sk_tx_queue_mapping out of the private section,
2164 	 * we must check if sk_tx_queue_clear() is called after
2165 	 * sock_copy() in sk_clone_lock().
2166 	 */
2167 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2168 		     offsetof(struct sock, sk_dontcopy_begin) ||
2169 		     offsetof(struct sock, sk_tx_queue_mapping) >=
2170 		     offsetof(struct sock, sk_dontcopy_end));
2171 
2172 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2173 
2174 	unsafe_memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2175 		      prot->obj_size - offsetof(struct sock, sk_dontcopy_end),
2176 		      /* alloc is larger than struct, see sk_prot_alloc() */);
2177 
2178 #ifdef CONFIG_SECURITY_NETWORK
2179 	nsk->sk_security = sptr;
2180 	security_sk_clone(osk, nsk);
2181 #endif
2182 }
2183 
2184 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2185 		int family)
2186 {
2187 	struct sock *sk;
2188 	struct kmem_cache *slab;
2189 
2190 	slab = prot->slab;
2191 	if (slab != NULL) {
2192 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2193 		if (!sk)
2194 			return sk;
2195 		if (want_init_on_alloc(priority))
2196 			sk_prot_clear_nulls(sk, prot->obj_size);
2197 	} else
2198 		sk = kmalloc(prot->obj_size, priority);
2199 
2200 	if (sk != NULL) {
2201 		if (security_sk_alloc(sk, family, priority))
2202 			goto out_free;
2203 
2204 		if (!try_module_get(prot->owner))
2205 			goto out_free_sec;
2206 	}
2207 
2208 	return sk;
2209 
2210 out_free_sec:
2211 	security_sk_free(sk);
2212 out_free:
2213 	if (slab != NULL)
2214 		kmem_cache_free(slab, sk);
2215 	else
2216 		kfree(sk);
2217 	return NULL;
2218 }
2219 
2220 static void sk_prot_free(struct proto *prot, struct sock *sk)
2221 {
2222 	struct kmem_cache *slab;
2223 	struct module *owner;
2224 
2225 	owner = prot->owner;
2226 	slab = prot->slab;
2227 
2228 	cgroup_sk_free(&sk->sk_cgrp_data);
2229 	mem_cgroup_sk_free(sk);
2230 	security_sk_free(sk);
2231 
2232 	sk_owner_put(sk);
2233 
2234 	if (slab != NULL)
2235 		kmem_cache_free(slab, sk);
2236 	else
2237 		kfree(sk);
2238 	module_put(owner);
2239 }
2240 
2241 /**
2242  *	sk_alloc - All socket objects are allocated here
2243  *	@net: the applicable net namespace
2244  *	@family: protocol family
2245  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2246  *	@prot: struct proto associated with this new sock instance
2247  *	@kern: is this to be a kernel socket?
2248  */
2249 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2250 		      struct proto *prot, int kern)
2251 {
2252 	struct sock *sk;
2253 
2254 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2255 	if (sk) {
2256 		sk->sk_family = family;
2257 		/*
2258 		 * See comment in struct sock definition to understand
2259 		 * why we need sk_prot_creator -acme
2260 		 */
2261 		sk->sk_prot = sk->sk_prot_creator = prot;
2262 		sk->sk_kern_sock = kern;
2263 		sock_lock_init(sk);
2264 		sk->sk_net_refcnt = kern ? 0 : 1;
2265 		if (likely(sk->sk_net_refcnt)) {
2266 			get_net_track(net, &sk->ns_tracker, priority);
2267 			sock_inuse_add(net, 1);
2268 		} else {
2269 			net_passive_inc(net);
2270 			__netns_tracker_alloc(net, &sk->ns_tracker,
2271 					      false, priority);
2272 		}
2273 
2274 		sock_net_set(sk, net);
2275 		refcount_set(&sk->sk_wmem_alloc, 1);
2276 
2277 		mem_cgroup_sk_alloc(sk);
2278 		cgroup_sk_alloc(&sk->sk_cgrp_data);
2279 		sock_update_classid(&sk->sk_cgrp_data);
2280 		sock_update_netprioidx(&sk->sk_cgrp_data);
2281 		sk_tx_queue_clear(sk);
2282 	}
2283 
2284 	return sk;
2285 }
2286 EXPORT_SYMBOL(sk_alloc);
2287 
2288 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2289  * grace period. This is the case for UDP sockets and TCP listeners.
2290  */
2291 static void __sk_destruct(struct rcu_head *head)
2292 {
2293 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2294 	struct net *net = sock_net(sk);
2295 	struct sk_filter *filter;
2296 
2297 	if (sk->sk_destruct)
2298 		sk->sk_destruct(sk);
2299 
2300 	filter = rcu_dereference_check(sk->sk_filter,
2301 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2302 	if (filter) {
2303 		sk_filter_uncharge(sk, filter);
2304 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2305 	}
2306 
2307 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2308 
2309 #ifdef CONFIG_BPF_SYSCALL
2310 	bpf_sk_storage_free(sk);
2311 #endif
2312 
2313 	if (atomic_read(&sk->sk_omem_alloc))
2314 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2315 			 __func__, atomic_read(&sk->sk_omem_alloc));
2316 
2317 	if (sk->sk_frag.page) {
2318 		put_page(sk->sk_frag.page);
2319 		sk->sk_frag.page = NULL;
2320 	}
2321 
2322 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2323 	put_cred(sk->sk_peer_cred);
2324 	put_pid(sk->sk_peer_pid);
2325 
2326 	if (likely(sk->sk_net_refcnt)) {
2327 		put_net_track(net, &sk->ns_tracker);
2328 	} else {
2329 		__netns_tracker_free(net, &sk->ns_tracker, false);
2330 		net_passive_dec(net);
2331 	}
2332 	sk_prot_free(sk->sk_prot_creator, sk);
2333 }
2334 
2335 void sk_net_refcnt_upgrade(struct sock *sk)
2336 {
2337 	struct net *net = sock_net(sk);
2338 
2339 	WARN_ON_ONCE(sk->sk_net_refcnt);
2340 	__netns_tracker_free(net, &sk->ns_tracker, false);
2341 	net_passive_dec(net);
2342 	sk->sk_net_refcnt = 1;
2343 	get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
2344 	sock_inuse_add(net, 1);
2345 }
2346 EXPORT_SYMBOL_GPL(sk_net_refcnt_upgrade);
2347 
2348 void sk_destruct(struct sock *sk)
2349 {
2350 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2351 
2352 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2353 		reuseport_detach_sock(sk);
2354 		use_call_rcu = true;
2355 	}
2356 
2357 	if (use_call_rcu)
2358 		call_rcu(&sk->sk_rcu, __sk_destruct);
2359 	else
2360 		__sk_destruct(&sk->sk_rcu);
2361 }
2362 
2363 static void __sk_free(struct sock *sk)
2364 {
2365 	if (likely(sk->sk_net_refcnt))
2366 		sock_inuse_add(sock_net(sk), -1);
2367 
2368 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2369 		sock_diag_broadcast_destroy(sk);
2370 	else
2371 		sk_destruct(sk);
2372 }
2373 
2374 void sk_free(struct sock *sk)
2375 {
2376 	/*
2377 	 * We subtract one from sk_wmem_alloc and can know if
2378 	 * some packets are still in some tx queue.
2379 	 * If not null, sock_wfree() will call __sk_free(sk) later
2380 	 */
2381 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2382 		__sk_free(sk);
2383 }
2384 EXPORT_SYMBOL(sk_free);
2385 
2386 static void sk_init_common(struct sock *sk)
2387 {
2388 	skb_queue_head_init(&sk->sk_receive_queue);
2389 	skb_queue_head_init(&sk->sk_write_queue);
2390 	skb_queue_head_init(&sk->sk_error_queue);
2391 
2392 	rwlock_init(&sk->sk_callback_lock);
2393 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2394 			af_rlock_keys + sk->sk_family,
2395 			af_family_rlock_key_strings[sk->sk_family]);
2396 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2397 			af_wlock_keys + sk->sk_family,
2398 			af_family_wlock_key_strings[sk->sk_family]);
2399 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2400 			af_elock_keys + sk->sk_family,
2401 			af_family_elock_key_strings[sk->sk_family]);
2402 	if (sk->sk_kern_sock)
2403 		lockdep_set_class_and_name(&sk->sk_callback_lock,
2404 			af_kern_callback_keys + sk->sk_family,
2405 			af_family_kern_clock_key_strings[sk->sk_family]);
2406 	else
2407 		lockdep_set_class_and_name(&sk->sk_callback_lock,
2408 			af_callback_keys + sk->sk_family,
2409 			af_family_clock_key_strings[sk->sk_family]);
2410 }
2411 
2412 /**
2413  *	sk_clone_lock - clone a socket, and lock its clone
2414  *	@sk: the socket to clone
2415  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2416  *
2417  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2418  */
2419 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2420 {
2421 	struct proto *prot = READ_ONCE(sk->sk_prot);
2422 	struct sk_filter *filter;
2423 	bool is_charged = true;
2424 	struct sock *newsk;
2425 
2426 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2427 	if (!newsk)
2428 		goto out;
2429 
2430 	sock_copy(newsk, sk);
2431 
2432 	newsk->sk_prot_creator = prot;
2433 
2434 	/* SANITY */
2435 	if (likely(newsk->sk_net_refcnt)) {
2436 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2437 		sock_inuse_add(sock_net(newsk), 1);
2438 	} else {
2439 		/* Kernel sockets are not elevating the struct net refcount.
2440 		 * Instead, use a tracker to more easily detect if a layer
2441 		 * is not properly dismantling its kernel sockets at netns
2442 		 * destroy time.
2443 		 */
2444 		net_passive_inc(sock_net(newsk));
2445 		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2446 				      false, priority);
2447 	}
2448 	sk_node_init(&newsk->sk_node);
2449 	sock_lock_init(newsk);
2450 	bh_lock_sock(newsk);
2451 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2452 	newsk->sk_backlog.len = 0;
2453 
2454 	atomic_set(&newsk->sk_rmem_alloc, 0);
2455 
2456 	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2457 	refcount_set(&newsk->sk_wmem_alloc, 1);
2458 
2459 	atomic_set(&newsk->sk_omem_alloc, 0);
2460 	sk_init_common(newsk);
2461 
2462 	newsk->sk_dst_cache	= NULL;
2463 	newsk->sk_dst_pending_confirm = 0;
2464 	newsk->sk_wmem_queued	= 0;
2465 	newsk->sk_forward_alloc = 0;
2466 	newsk->sk_reserved_mem  = 0;
2467 	atomic_set(&newsk->sk_drops, 0);
2468 	newsk->sk_send_head	= NULL;
2469 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2470 	atomic_set(&newsk->sk_zckey, 0);
2471 
2472 	sock_reset_flag(newsk, SOCK_DONE);
2473 
2474 	/* sk->sk_memcg will be populated at accept() time */
2475 	newsk->sk_memcg = NULL;
2476 
2477 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2478 
2479 	rcu_read_lock();
2480 	filter = rcu_dereference(sk->sk_filter);
2481 	if (filter != NULL)
2482 		/* though it's an empty new sock, the charging may fail
2483 		 * if sysctl_optmem_max was changed between creation of
2484 		 * original socket and cloning
2485 		 */
2486 		is_charged = sk_filter_charge(newsk, filter);
2487 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2488 	rcu_read_unlock();
2489 
2490 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2491 		/* We need to make sure that we don't uncharge the new
2492 		 * socket if we couldn't charge it in the first place
2493 		 * as otherwise we uncharge the parent's filter.
2494 		 */
2495 		if (!is_charged)
2496 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2497 
2498 		goto free;
2499 	}
2500 
2501 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2502 
2503 	if (bpf_sk_storage_clone(sk, newsk))
2504 		goto free;
2505 
2506 	/* Clear sk_user_data if parent had the pointer tagged
2507 	 * as not suitable for copying when cloning.
2508 	 */
2509 	if (sk_user_data_is_nocopy(newsk))
2510 		newsk->sk_user_data = NULL;
2511 
2512 	newsk->sk_err	   = 0;
2513 	newsk->sk_err_soft = 0;
2514 	newsk->sk_priority = 0;
2515 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2516 
2517 	/* Before updating sk_refcnt, we must commit prior changes to memory
2518 	 * (Documentation/RCU/rculist_nulls.rst for details)
2519 	 */
2520 	smp_wmb();
2521 	refcount_set(&newsk->sk_refcnt, 2);
2522 
2523 	sk_set_socket(newsk, NULL);
2524 	sk_tx_queue_clear(newsk);
2525 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2526 
2527 	if (newsk->sk_prot->sockets_allocated)
2528 		sk_sockets_allocated_inc(newsk);
2529 
2530 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2531 		net_enable_timestamp();
2532 out:
2533 	return newsk;
2534 free:
2535 	/* It is still raw copy of parent, so invalidate
2536 	 * destructor and make plain sk_free()
2537 	 */
2538 	newsk->sk_destruct = NULL;
2539 	bh_unlock_sock(newsk);
2540 	sk_free(newsk);
2541 	newsk = NULL;
2542 	goto out;
2543 }
2544 EXPORT_SYMBOL_GPL(sk_clone_lock);
2545 
2546 static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst)
2547 {
2548 	bool is_ipv6 = false;
2549 	u32 max_size;
2550 
2551 #if IS_ENABLED(CONFIG_IPV6)
2552 	is_ipv6 = (sk->sk_family == AF_INET6 &&
2553 		   !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2554 #endif
2555 	/* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2556 	max_size = is_ipv6 ? READ_ONCE(dst->dev->gso_max_size) :
2557 			READ_ONCE(dst->dev->gso_ipv4_max_size);
2558 	if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2559 		max_size = GSO_LEGACY_MAX_SIZE;
2560 
2561 	return max_size - (MAX_TCP_HEADER + 1);
2562 }
2563 
2564 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2565 {
2566 	u32 max_segs = 1;
2567 
2568 	sk->sk_route_caps = dst->dev->features;
2569 	if (sk_is_tcp(sk)) {
2570 		struct inet_connection_sock *icsk = inet_csk(sk);
2571 
2572 		sk->sk_route_caps |= NETIF_F_GSO;
2573 		icsk->icsk_ack.dst_quick_ack = dst_metric(dst, RTAX_QUICKACK);
2574 	}
2575 	if (sk->sk_route_caps & NETIF_F_GSO)
2576 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2577 	if (unlikely(sk->sk_gso_disabled))
2578 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2579 	if (sk_can_gso(sk)) {
2580 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2581 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2582 		} else {
2583 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2584 			sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst);
2585 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2586 			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2587 		}
2588 	}
2589 	sk->sk_gso_max_segs = max_segs;
2590 	sk_dst_set(sk, dst);
2591 }
2592 EXPORT_SYMBOL_GPL(sk_setup_caps);
2593 
2594 /*
2595  *	Simple resource managers for sockets.
2596  */
2597 
2598 
2599 /*
2600  * Write buffer destructor automatically called from kfree_skb.
2601  */
2602 void sock_wfree(struct sk_buff *skb)
2603 {
2604 	struct sock *sk = skb->sk;
2605 	unsigned int len = skb->truesize;
2606 	bool free;
2607 
2608 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2609 		if (sock_flag(sk, SOCK_RCU_FREE) &&
2610 		    sk->sk_write_space == sock_def_write_space) {
2611 			rcu_read_lock();
2612 			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2613 			sock_def_write_space_wfree(sk);
2614 			rcu_read_unlock();
2615 			if (unlikely(free))
2616 				__sk_free(sk);
2617 			return;
2618 		}
2619 
2620 		/*
2621 		 * Keep a reference on sk_wmem_alloc, this will be released
2622 		 * after sk_write_space() call
2623 		 */
2624 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2625 		sk->sk_write_space(sk);
2626 		len = 1;
2627 	}
2628 	/*
2629 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2630 	 * could not do because of in-flight packets
2631 	 */
2632 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2633 		__sk_free(sk);
2634 }
2635 EXPORT_SYMBOL(sock_wfree);
2636 
2637 /* This variant of sock_wfree() is used by TCP,
2638  * since it sets SOCK_USE_WRITE_QUEUE.
2639  */
2640 void __sock_wfree(struct sk_buff *skb)
2641 {
2642 	struct sock *sk = skb->sk;
2643 
2644 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2645 		__sk_free(sk);
2646 }
2647 
2648 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2649 {
2650 	skb_orphan(skb);
2651 #ifdef CONFIG_INET
2652 	if (unlikely(!sk_fullsock(sk)))
2653 		return skb_set_owner_edemux(skb, sk);
2654 #endif
2655 	skb->sk = sk;
2656 	skb->destructor = sock_wfree;
2657 	skb_set_hash_from_sk(skb, sk);
2658 	/*
2659 	 * We used to take a refcount on sk, but following operation
2660 	 * is enough to guarantee sk_free() won't free this sock until
2661 	 * all in-flight packets are completed
2662 	 */
2663 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2664 }
2665 EXPORT_SYMBOL(skb_set_owner_w);
2666 
2667 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2668 {
2669 	/* Drivers depend on in-order delivery for crypto offload,
2670 	 * partial orphan breaks out-of-order-OK logic.
2671 	 */
2672 	if (skb_is_decrypted(skb))
2673 		return false;
2674 
2675 	return (skb->destructor == sock_wfree ||
2676 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2677 }
2678 
2679 /* This helper is used by netem, as it can hold packets in its
2680  * delay queue. We want to allow the owner socket to send more
2681  * packets, as if they were already TX completed by a typical driver.
2682  * But we also want to keep skb->sk set because some packet schedulers
2683  * rely on it (sch_fq for example).
2684  */
2685 void skb_orphan_partial(struct sk_buff *skb)
2686 {
2687 	if (skb_is_tcp_pure_ack(skb))
2688 		return;
2689 
2690 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2691 		return;
2692 
2693 	skb_orphan(skb);
2694 }
2695 EXPORT_SYMBOL(skb_orphan_partial);
2696 
2697 /*
2698  * Read buffer destructor automatically called from kfree_skb.
2699  */
2700 void sock_rfree(struct sk_buff *skb)
2701 {
2702 	struct sock *sk = skb->sk;
2703 	unsigned int len = skb->truesize;
2704 
2705 	atomic_sub(len, &sk->sk_rmem_alloc);
2706 	sk_mem_uncharge(sk, len);
2707 }
2708 EXPORT_SYMBOL(sock_rfree);
2709 
2710 /*
2711  * Buffer destructor for skbs that are not used directly in read or write
2712  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2713  */
2714 void sock_efree(struct sk_buff *skb)
2715 {
2716 	sock_put(skb->sk);
2717 }
2718 EXPORT_SYMBOL(sock_efree);
2719 
2720 /* Buffer destructor for prefetch/receive path where reference count may
2721  * not be held, e.g. for listen sockets.
2722  */
2723 #ifdef CONFIG_INET
2724 void sock_pfree(struct sk_buff *skb)
2725 {
2726 	struct sock *sk = skb->sk;
2727 
2728 	if (!sk_is_refcounted(sk))
2729 		return;
2730 
2731 	if (sk->sk_state == TCP_NEW_SYN_RECV && inet_reqsk(sk)->syncookie) {
2732 		inet_reqsk(sk)->rsk_listener = NULL;
2733 		reqsk_free(inet_reqsk(sk));
2734 		return;
2735 	}
2736 
2737 	sock_gen_put(sk);
2738 }
2739 EXPORT_SYMBOL(sock_pfree);
2740 #endif /* CONFIG_INET */
2741 
2742 kuid_t sock_i_uid(struct sock *sk)
2743 {
2744 	kuid_t uid;
2745 
2746 	read_lock_bh(&sk->sk_callback_lock);
2747 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2748 	read_unlock_bh(&sk->sk_callback_lock);
2749 	return uid;
2750 }
2751 EXPORT_SYMBOL(sock_i_uid);
2752 
2753 unsigned long __sock_i_ino(struct sock *sk)
2754 {
2755 	unsigned long ino;
2756 
2757 	read_lock(&sk->sk_callback_lock);
2758 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2759 	read_unlock(&sk->sk_callback_lock);
2760 	return ino;
2761 }
2762 EXPORT_SYMBOL(__sock_i_ino);
2763 
2764 unsigned long sock_i_ino(struct sock *sk)
2765 {
2766 	unsigned long ino;
2767 
2768 	local_bh_disable();
2769 	ino = __sock_i_ino(sk);
2770 	local_bh_enable();
2771 	return ino;
2772 }
2773 EXPORT_SYMBOL(sock_i_ino);
2774 
2775 /*
2776  * Allocate a skb from the socket's send buffer.
2777  */
2778 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2779 			     gfp_t priority)
2780 {
2781 	if (force ||
2782 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2783 		struct sk_buff *skb = alloc_skb(size, priority);
2784 
2785 		if (skb) {
2786 			skb_set_owner_w(skb, sk);
2787 			return skb;
2788 		}
2789 	}
2790 	return NULL;
2791 }
2792 EXPORT_SYMBOL(sock_wmalloc);
2793 
2794 static void sock_ofree(struct sk_buff *skb)
2795 {
2796 	struct sock *sk = skb->sk;
2797 
2798 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2799 }
2800 
2801 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2802 			     gfp_t priority)
2803 {
2804 	struct sk_buff *skb;
2805 
2806 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2807 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2808 	    READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2809 		return NULL;
2810 
2811 	skb = alloc_skb(size, priority);
2812 	if (!skb)
2813 		return NULL;
2814 
2815 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2816 	skb->sk = sk;
2817 	skb->destructor = sock_ofree;
2818 	return skb;
2819 }
2820 
2821 /*
2822  * Allocate a memory block from the socket's option memory buffer.
2823  */
2824 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2825 {
2826 	int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2827 
2828 	if ((unsigned int)size <= optmem_max &&
2829 	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2830 		void *mem;
2831 		/* First do the add, to avoid the race if kmalloc
2832 		 * might sleep.
2833 		 */
2834 		atomic_add(size, &sk->sk_omem_alloc);
2835 		mem = kmalloc(size, priority);
2836 		if (mem)
2837 			return mem;
2838 		atomic_sub(size, &sk->sk_omem_alloc);
2839 	}
2840 	return NULL;
2841 }
2842 EXPORT_SYMBOL(sock_kmalloc);
2843 
2844 /*
2845  * Duplicate the input "src" memory block using the socket's
2846  * option memory buffer.
2847  */
2848 void *sock_kmemdup(struct sock *sk, const void *src,
2849 		   int size, gfp_t priority)
2850 {
2851 	void *mem;
2852 
2853 	mem = sock_kmalloc(sk, size, priority);
2854 	if (mem)
2855 		memcpy(mem, src, size);
2856 	return mem;
2857 }
2858 EXPORT_SYMBOL(sock_kmemdup);
2859 
2860 /* Free an option memory block. Note, we actually want the inline
2861  * here as this allows gcc to detect the nullify and fold away the
2862  * condition entirely.
2863  */
2864 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2865 				  const bool nullify)
2866 {
2867 	if (WARN_ON_ONCE(!mem))
2868 		return;
2869 	if (nullify)
2870 		kfree_sensitive(mem);
2871 	else
2872 		kfree(mem);
2873 	atomic_sub(size, &sk->sk_omem_alloc);
2874 }
2875 
2876 void sock_kfree_s(struct sock *sk, void *mem, int size)
2877 {
2878 	__sock_kfree_s(sk, mem, size, false);
2879 }
2880 EXPORT_SYMBOL(sock_kfree_s);
2881 
2882 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2883 {
2884 	__sock_kfree_s(sk, mem, size, true);
2885 }
2886 EXPORT_SYMBOL(sock_kzfree_s);
2887 
2888 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2889    I think, these locks should be removed for datagram sockets.
2890  */
2891 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2892 {
2893 	DEFINE_WAIT(wait);
2894 
2895 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2896 	for (;;) {
2897 		if (!timeo)
2898 			break;
2899 		if (signal_pending(current))
2900 			break;
2901 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2902 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2903 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2904 			break;
2905 		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2906 			break;
2907 		if (READ_ONCE(sk->sk_err))
2908 			break;
2909 		timeo = schedule_timeout(timeo);
2910 	}
2911 	finish_wait(sk_sleep(sk), &wait);
2912 	return timeo;
2913 }
2914 
2915 
2916 /*
2917  *	Generic send/receive buffer handlers
2918  */
2919 
2920 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2921 				     unsigned long data_len, int noblock,
2922 				     int *errcode, int max_page_order)
2923 {
2924 	struct sk_buff *skb;
2925 	long timeo;
2926 	int err;
2927 
2928 	timeo = sock_sndtimeo(sk, noblock);
2929 	for (;;) {
2930 		err = sock_error(sk);
2931 		if (err != 0)
2932 			goto failure;
2933 
2934 		err = -EPIPE;
2935 		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2936 			goto failure;
2937 
2938 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2939 			break;
2940 
2941 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2942 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2943 		err = -EAGAIN;
2944 		if (!timeo)
2945 			goto failure;
2946 		if (signal_pending(current))
2947 			goto interrupted;
2948 		timeo = sock_wait_for_wmem(sk, timeo);
2949 	}
2950 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2951 				   errcode, sk->sk_allocation);
2952 	if (skb)
2953 		skb_set_owner_w(skb, sk);
2954 	return skb;
2955 
2956 interrupted:
2957 	err = sock_intr_errno(timeo);
2958 failure:
2959 	*errcode = err;
2960 	return NULL;
2961 }
2962 EXPORT_SYMBOL(sock_alloc_send_pskb);
2963 
2964 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2965 		     struct sockcm_cookie *sockc)
2966 {
2967 	u32 tsflags;
2968 
2969 	BUILD_BUG_ON(SOF_TIMESTAMPING_LAST == (1 << 31));
2970 
2971 	switch (cmsg->cmsg_type) {
2972 	case SO_MARK:
2973 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2974 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2975 			return -EPERM;
2976 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2977 			return -EINVAL;
2978 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2979 		break;
2980 	case SO_TIMESTAMPING_OLD:
2981 	case SO_TIMESTAMPING_NEW:
2982 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2983 			return -EINVAL;
2984 
2985 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2986 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2987 			return -EINVAL;
2988 
2989 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2990 		sockc->tsflags |= tsflags;
2991 		break;
2992 	case SCM_TXTIME:
2993 		if (!sock_flag(sk, SOCK_TXTIME))
2994 			return -EINVAL;
2995 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2996 			return -EINVAL;
2997 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2998 		break;
2999 	case SCM_TS_OPT_ID:
3000 		if (sk_is_tcp(sk))
3001 			return -EINVAL;
3002 		tsflags = READ_ONCE(sk->sk_tsflags);
3003 		if (!(tsflags & SOF_TIMESTAMPING_OPT_ID))
3004 			return -EINVAL;
3005 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3006 			return -EINVAL;
3007 		sockc->ts_opt_id = *(u32 *)CMSG_DATA(cmsg);
3008 		sockc->tsflags |= SOCKCM_FLAG_TS_OPT_ID;
3009 		break;
3010 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
3011 	case SCM_RIGHTS:
3012 	case SCM_CREDENTIALS:
3013 		break;
3014 	case SO_PRIORITY:
3015 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3016 			return -EINVAL;
3017 		if (!sk_set_prio_allowed(sk, *(u32 *)CMSG_DATA(cmsg)))
3018 			return -EPERM;
3019 		sockc->priority = *(u32 *)CMSG_DATA(cmsg);
3020 		break;
3021 	case SCM_DEVMEM_DMABUF:
3022 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3023 			return -EINVAL;
3024 		sockc->dmabuf_id = *(u32 *)CMSG_DATA(cmsg);
3025 		break;
3026 	default:
3027 		return -EINVAL;
3028 	}
3029 	return 0;
3030 }
3031 EXPORT_SYMBOL(__sock_cmsg_send);
3032 
3033 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
3034 		   struct sockcm_cookie *sockc)
3035 {
3036 	struct cmsghdr *cmsg;
3037 	int ret;
3038 
3039 	for_each_cmsghdr(cmsg, msg) {
3040 		if (!CMSG_OK(msg, cmsg))
3041 			return -EINVAL;
3042 		if (cmsg->cmsg_level != SOL_SOCKET)
3043 			continue;
3044 		ret = __sock_cmsg_send(sk, cmsg, sockc);
3045 		if (ret)
3046 			return ret;
3047 	}
3048 	return 0;
3049 }
3050 EXPORT_SYMBOL(sock_cmsg_send);
3051 
3052 static void sk_enter_memory_pressure(struct sock *sk)
3053 {
3054 	if (!sk->sk_prot->enter_memory_pressure)
3055 		return;
3056 
3057 	sk->sk_prot->enter_memory_pressure(sk);
3058 }
3059 
3060 static void sk_leave_memory_pressure(struct sock *sk)
3061 {
3062 	if (sk->sk_prot->leave_memory_pressure) {
3063 		INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
3064 				     tcp_leave_memory_pressure, sk);
3065 	} else {
3066 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
3067 
3068 		if (memory_pressure && READ_ONCE(*memory_pressure))
3069 			WRITE_ONCE(*memory_pressure, 0);
3070 	}
3071 }
3072 
3073 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
3074 
3075 /**
3076  * skb_page_frag_refill - check that a page_frag contains enough room
3077  * @sz: minimum size of the fragment we want to get
3078  * @pfrag: pointer to page_frag
3079  * @gfp: priority for memory allocation
3080  *
3081  * Note: While this allocator tries to use high order pages, there is
3082  * no guarantee that allocations succeed. Therefore, @sz MUST be
3083  * less or equal than PAGE_SIZE.
3084  */
3085 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
3086 {
3087 	if (pfrag->page) {
3088 		if (page_ref_count(pfrag->page) == 1) {
3089 			pfrag->offset = 0;
3090 			return true;
3091 		}
3092 		if (pfrag->offset + sz <= pfrag->size)
3093 			return true;
3094 		put_page(pfrag->page);
3095 	}
3096 
3097 	pfrag->offset = 0;
3098 	if (SKB_FRAG_PAGE_ORDER &&
3099 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
3100 		/* Avoid direct reclaim but allow kswapd to wake */
3101 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
3102 					  __GFP_COMP | __GFP_NOWARN |
3103 					  __GFP_NORETRY,
3104 					  SKB_FRAG_PAGE_ORDER);
3105 		if (likely(pfrag->page)) {
3106 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
3107 			return true;
3108 		}
3109 	}
3110 	pfrag->page = alloc_page(gfp);
3111 	if (likely(pfrag->page)) {
3112 		pfrag->size = PAGE_SIZE;
3113 		return true;
3114 	}
3115 	return false;
3116 }
3117 EXPORT_SYMBOL(skb_page_frag_refill);
3118 
3119 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
3120 {
3121 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
3122 		return true;
3123 
3124 	sk_enter_memory_pressure(sk);
3125 	sk_stream_moderate_sndbuf(sk);
3126 	return false;
3127 }
3128 EXPORT_SYMBOL(sk_page_frag_refill);
3129 
3130 void __lock_sock(struct sock *sk)
3131 	__releases(&sk->sk_lock.slock)
3132 	__acquires(&sk->sk_lock.slock)
3133 {
3134 	DEFINE_WAIT(wait);
3135 
3136 	for (;;) {
3137 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
3138 					TASK_UNINTERRUPTIBLE);
3139 		spin_unlock_bh(&sk->sk_lock.slock);
3140 		schedule();
3141 		spin_lock_bh(&sk->sk_lock.slock);
3142 		if (!sock_owned_by_user(sk))
3143 			break;
3144 	}
3145 	finish_wait(&sk->sk_lock.wq, &wait);
3146 }
3147 
3148 void __release_sock(struct sock *sk)
3149 	__releases(&sk->sk_lock.slock)
3150 	__acquires(&sk->sk_lock.slock)
3151 {
3152 	struct sk_buff *skb, *next;
3153 
3154 	while ((skb = sk->sk_backlog.head) != NULL) {
3155 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
3156 
3157 		spin_unlock_bh(&sk->sk_lock.slock);
3158 
3159 		do {
3160 			next = skb->next;
3161 			prefetch(next);
3162 			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
3163 			skb_mark_not_on_list(skb);
3164 			sk_backlog_rcv(sk, skb);
3165 
3166 			cond_resched();
3167 
3168 			skb = next;
3169 		} while (skb != NULL);
3170 
3171 		spin_lock_bh(&sk->sk_lock.slock);
3172 	}
3173 
3174 	/*
3175 	 * Doing the zeroing here guarantee we can not loop forever
3176 	 * while a wild producer attempts to flood us.
3177 	 */
3178 	sk->sk_backlog.len = 0;
3179 }
3180 
3181 void __sk_flush_backlog(struct sock *sk)
3182 {
3183 	spin_lock_bh(&sk->sk_lock.slock);
3184 	__release_sock(sk);
3185 
3186 	if (sk->sk_prot->release_cb)
3187 		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3188 				     tcp_release_cb, sk);
3189 
3190 	spin_unlock_bh(&sk->sk_lock.slock);
3191 }
3192 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3193 
3194 /**
3195  * sk_wait_data - wait for data to arrive at sk_receive_queue
3196  * @sk:    sock to wait on
3197  * @timeo: for how long
3198  * @skb:   last skb seen on sk_receive_queue
3199  *
3200  * Now socket state including sk->sk_err is changed only under lock,
3201  * hence we may omit checks after joining wait queue.
3202  * We check receive queue before schedule() only as optimization;
3203  * it is very likely that release_sock() added new data.
3204  */
3205 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3206 {
3207 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
3208 	int rc;
3209 
3210 	add_wait_queue(sk_sleep(sk), &wait);
3211 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3212 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3213 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3214 	remove_wait_queue(sk_sleep(sk), &wait);
3215 	return rc;
3216 }
3217 EXPORT_SYMBOL(sk_wait_data);
3218 
3219 /**
3220  *	__sk_mem_raise_allocated - increase memory_allocated
3221  *	@sk: socket
3222  *	@size: memory size to allocate
3223  *	@amt: pages to allocate
3224  *	@kind: allocation type
3225  *
3226  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3227  *
3228  *	Unlike the globally shared limits among the sockets under same protocol,
3229  *	consuming the budget of a memcg won't have direct effect on other ones.
3230  *	So be optimistic about memcg's tolerance, and leave the callers to decide
3231  *	whether or not to raise allocated through sk_under_memory_pressure() or
3232  *	its variants.
3233  */
3234 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3235 {
3236 	struct mem_cgroup *memcg = mem_cgroup_sockets_enabled ? sk->sk_memcg : NULL;
3237 	struct proto *prot = sk->sk_prot;
3238 	bool charged = false;
3239 	long allocated;
3240 
3241 	sk_memory_allocated_add(sk, amt);
3242 	allocated = sk_memory_allocated(sk);
3243 
3244 	if (memcg) {
3245 		if (!mem_cgroup_charge_skmem(memcg, amt, gfp_memcg_charge()))
3246 			goto suppress_allocation;
3247 		charged = true;
3248 	}
3249 
3250 	/* Under limit. */
3251 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
3252 		sk_leave_memory_pressure(sk);
3253 		return 1;
3254 	}
3255 
3256 	/* Under pressure. */
3257 	if (allocated > sk_prot_mem_limits(sk, 1))
3258 		sk_enter_memory_pressure(sk);
3259 
3260 	/* Over hard limit. */
3261 	if (allocated > sk_prot_mem_limits(sk, 2))
3262 		goto suppress_allocation;
3263 
3264 	/* Guarantee minimum buffer size under pressure (either global
3265 	 * or memcg) to make sure features described in RFC 7323 (TCP
3266 	 * Extensions for High Performance) work properly.
3267 	 *
3268 	 * This rule does NOT stand when exceeds global or memcg's hard
3269 	 * limit, or else a DoS attack can be taken place by spawning
3270 	 * lots of sockets whose usage are under minimum buffer size.
3271 	 */
3272 	if (kind == SK_MEM_RECV) {
3273 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3274 			return 1;
3275 
3276 	} else { /* SK_MEM_SEND */
3277 		int wmem0 = sk_get_wmem0(sk, prot);
3278 
3279 		if (sk->sk_type == SOCK_STREAM) {
3280 			if (sk->sk_wmem_queued < wmem0)
3281 				return 1;
3282 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3283 				return 1;
3284 		}
3285 	}
3286 
3287 	if (sk_has_memory_pressure(sk)) {
3288 		u64 alloc;
3289 
3290 		/* The following 'average' heuristic is within the
3291 		 * scope of global accounting, so it only makes
3292 		 * sense for global memory pressure.
3293 		 */
3294 		if (!sk_under_global_memory_pressure(sk))
3295 			return 1;
3296 
3297 		/* Try to be fair among all the sockets under global
3298 		 * pressure by allowing the ones that below average
3299 		 * usage to raise.
3300 		 */
3301 		alloc = sk_sockets_allocated_read_positive(sk);
3302 		if (sk_prot_mem_limits(sk, 2) > alloc *
3303 		    sk_mem_pages(sk->sk_wmem_queued +
3304 				 atomic_read(&sk->sk_rmem_alloc) +
3305 				 sk->sk_forward_alloc))
3306 			return 1;
3307 	}
3308 
3309 suppress_allocation:
3310 
3311 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3312 		sk_stream_moderate_sndbuf(sk);
3313 
3314 		/* Fail only if socket is _under_ its sndbuf.
3315 		 * In this case we cannot block, so that we have to fail.
3316 		 */
3317 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3318 			/* Force charge with __GFP_NOFAIL */
3319 			if (memcg && !charged) {
3320 				mem_cgroup_charge_skmem(memcg, amt,
3321 					gfp_memcg_charge() | __GFP_NOFAIL);
3322 			}
3323 			return 1;
3324 		}
3325 	}
3326 
3327 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3328 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3329 
3330 	sk_memory_allocated_sub(sk, amt);
3331 
3332 	if (charged)
3333 		mem_cgroup_uncharge_skmem(memcg, amt);
3334 
3335 	return 0;
3336 }
3337 
3338 /**
3339  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3340  *	@sk: socket
3341  *	@size: memory size to allocate
3342  *	@kind: allocation type
3343  *
3344  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3345  *	rmem allocation. This function assumes that protocols which have
3346  *	memory_pressure use sk_wmem_queued as write buffer accounting.
3347  */
3348 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3349 {
3350 	int ret, amt = sk_mem_pages(size);
3351 
3352 	sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3353 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3354 	if (!ret)
3355 		sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3356 	return ret;
3357 }
3358 EXPORT_SYMBOL(__sk_mem_schedule);
3359 
3360 /**
3361  *	__sk_mem_reduce_allocated - reclaim memory_allocated
3362  *	@sk: socket
3363  *	@amount: number of quanta
3364  *
3365  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3366  */
3367 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3368 {
3369 	sk_memory_allocated_sub(sk, amount);
3370 
3371 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3372 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3373 
3374 	if (sk_under_global_memory_pressure(sk) &&
3375 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3376 		sk_leave_memory_pressure(sk);
3377 }
3378 
3379 /**
3380  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3381  *	@sk: socket
3382  *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3383  */
3384 void __sk_mem_reclaim(struct sock *sk, int amount)
3385 {
3386 	amount >>= PAGE_SHIFT;
3387 	sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3388 	__sk_mem_reduce_allocated(sk, amount);
3389 }
3390 EXPORT_SYMBOL(__sk_mem_reclaim);
3391 
3392 int sk_set_peek_off(struct sock *sk, int val)
3393 {
3394 	WRITE_ONCE(sk->sk_peek_off, val);
3395 	return 0;
3396 }
3397 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3398 
3399 /*
3400  * Set of default routines for initialising struct proto_ops when
3401  * the protocol does not support a particular function. In certain
3402  * cases where it makes no sense for a protocol to have a "do nothing"
3403  * function, some default processing is provided.
3404  */
3405 
3406 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3407 {
3408 	return -EOPNOTSUPP;
3409 }
3410 EXPORT_SYMBOL(sock_no_bind);
3411 
3412 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3413 		    int len, int flags)
3414 {
3415 	return -EOPNOTSUPP;
3416 }
3417 EXPORT_SYMBOL(sock_no_connect);
3418 
3419 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3420 {
3421 	return -EOPNOTSUPP;
3422 }
3423 EXPORT_SYMBOL(sock_no_socketpair);
3424 
3425 int sock_no_accept(struct socket *sock, struct socket *newsock,
3426 		   struct proto_accept_arg *arg)
3427 {
3428 	return -EOPNOTSUPP;
3429 }
3430 EXPORT_SYMBOL(sock_no_accept);
3431 
3432 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3433 		    int peer)
3434 {
3435 	return -EOPNOTSUPP;
3436 }
3437 EXPORT_SYMBOL(sock_no_getname);
3438 
3439 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3440 {
3441 	return -EOPNOTSUPP;
3442 }
3443 EXPORT_SYMBOL(sock_no_ioctl);
3444 
3445 int sock_no_listen(struct socket *sock, int backlog)
3446 {
3447 	return -EOPNOTSUPP;
3448 }
3449 EXPORT_SYMBOL(sock_no_listen);
3450 
3451 int sock_no_shutdown(struct socket *sock, int how)
3452 {
3453 	return -EOPNOTSUPP;
3454 }
3455 EXPORT_SYMBOL(sock_no_shutdown);
3456 
3457 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3458 {
3459 	return -EOPNOTSUPP;
3460 }
3461 EXPORT_SYMBOL(sock_no_sendmsg);
3462 
3463 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3464 {
3465 	return -EOPNOTSUPP;
3466 }
3467 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3468 
3469 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3470 		    int flags)
3471 {
3472 	return -EOPNOTSUPP;
3473 }
3474 EXPORT_SYMBOL(sock_no_recvmsg);
3475 
3476 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3477 {
3478 	/* Mirror missing mmap method error code */
3479 	return -ENODEV;
3480 }
3481 EXPORT_SYMBOL(sock_no_mmap);
3482 
3483 /*
3484  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3485  * various sock-based usage counts.
3486  */
3487 void __receive_sock(struct file *file)
3488 {
3489 	struct socket *sock;
3490 
3491 	sock = sock_from_file(file);
3492 	if (sock) {
3493 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3494 		sock_update_classid(&sock->sk->sk_cgrp_data);
3495 	}
3496 }
3497 
3498 /*
3499  *	Default Socket Callbacks
3500  */
3501 
3502 static void sock_def_wakeup(struct sock *sk)
3503 {
3504 	struct socket_wq *wq;
3505 
3506 	rcu_read_lock();
3507 	wq = rcu_dereference(sk->sk_wq);
3508 	if (skwq_has_sleeper(wq))
3509 		wake_up_interruptible_all(&wq->wait);
3510 	rcu_read_unlock();
3511 }
3512 
3513 static void sock_def_error_report(struct sock *sk)
3514 {
3515 	struct socket_wq *wq;
3516 
3517 	rcu_read_lock();
3518 	wq = rcu_dereference(sk->sk_wq);
3519 	if (skwq_has_sleeper(wq))
3520 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3521 	sk_wake_async_rcu(sk, SOCK_WAKE_IO, POLL_ERR);
3522 	rcu_read_unlock();
3523 }
3524 
3525 void sock_def_readable(struct sock *sk)
3526 {
3527 	struct socket_wq *wq;
3528 
3529 	trace_sk_data_ready(sk);
3530 
3531 	rcu_read_lock();
3532 	wq = rcu_dereference(sk->sk_wq);
3533 	if (skwq_has_sleeper(wq))
3534 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3535 						EPOLLRDNORM | EPOLLRDBAND);
3536 	sk_wake_async_rcu(sk, SOCK_WAKE_WAITD, POLL_IN);
3537 	rcu_read_unlock();
3538 }
3539 
3540 static void sock_def_write_space(struct sock *sk)
3541 {
3542 	struct socket_wq *wq;
3543 
3544 	rcu_read_lock();
3545 
3546 	/* Do not wake up a writer until he can make "significant"
3547 	 * progress.  --DaveM
3548 	 */
3549 	if (sock_writeable(sk)) {
3550 		wq = rcu_dereference(sk->sk_wq);
3551 		if (skwq_has_sleeper(wq))
3552 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3553 						EPOLLWRNORM | EPOLLWRBAND);
3554 
3555 		/* Should agree with poll, otherwise some programs break */
3556 		sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3557 	}
3558 
3559 	rcu_read_unlock();
3560 }
3561 
3562 /* An optimised version of sock_def_write_space(), should only be called
3563  * for SOCK_RCU_FREE sockets under RCU read section and after putting
3564  * ->sk_wmem_alloc.
3565  */
3566 static void sock_def_write_space_wfree(struct sock *sk)
3567 {
3568 	/* Do not wake up a writer until he can make "significant"
3569 	 * progress.  --DaveM
3570 	 */
3571 	if (sock_writeable(sk)) {
3572 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3573 
3574 		/* rely on refcount_sub from sock_wfree() */
3575 		smp_mb__after_atomic();
3576 		if (wq && waitqueue_active(&wq->wait))
3577 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3578 						EPOLLWRNORM | EPOLLWRBAND);
3579 
3580 		/* Should agree with poll, otherwise some programs break */
3581 		sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3582 	}
3583 }
3584 
3585 static void sock_def_destruct(struct sock *sk)
3586 {
3587 }
3588 
3589 void sk_send_sigurg(struct sock *sk)
3590 {
3591 	if (sk->sk_socket && sk->sk_socket->file)
3592 		if (send_sigurg(sk->sk_socket->file))
3593 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3594 }
3595 EXPORT_SYMBOL(sk_send_sigurg);
3596 
3597 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3598 		    unsigned long expires)
3599 {
3600 	if (!mod_timer(timer, expires))
3601 		sock_hold(sk);
3602 }
3603 EXPORT_SYMBOL(sk_reset_timer);
3604 
3605 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3606 {
3607 	if (timer_delete(timer))
3608 		__sock_put(sk);
3609 }
3610 EXPORT_SYMBOL(sk_stop_timer);
3611 
3612 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3613 {
3614 	if (timer_delete_sync(timer))
3615 		__sock_put(sk);
3616 }
3617 EXPORT_SYMBOL(sk_stop_timer_sync);
3618 
3619 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3620 {
3621 	sk_init_common(sk);
3622 	sk->sk_send_head	=	NULL;
3623 
3624 	timer_setup(&sk->sk_timer, NULL, 0);
3625 
3626 	sk->sk_allocation	=	GFP_KERNEL;
3627 	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3628 	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3629 	sk->sk_state		=	TCP_CLOSE;
3630 	sk->sk_use_task_frag	=	true;
3631 	sk_set_socket(sk, sock);
3632 
3633 	sock_set_flag(sk, SOCK_ZAPPED);
3634 
3635 	if (sock) {
3636 		sk->sk_type	=	sock->type;
3637 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3638 		sock->sk	=	sk;
3639 	} else {
3640 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3641 	}
3642 	sk->sk_uid	=	uid;
3643 
3644 	sk->sk_state_change	=	sock_def_wakeup;
3645 	sk->sk_data_ready	=	sock_def_readable;
3646 	sk->sk_write_space	=	sock_def_write_space;
3647 	sk->sk_error_report	=	sock_def_error_report;
3648 	sk->sk_destruct		=	sock_def_destruct;
3649 
3650 	sk->sk_frag.page	=	NULL;
3651 	sk->sk_frag.offset	=	0;
3652 	sk->sk_peek_off		=	-1;
3653 
3654 	sk->sk_peer_pid 	=	NULL;
3655 	sk->sk_peer_cred	=	NULL;
3656 	spin_lock_init(&sk->sk_peer_lock);
3657 
3658 	sk->sk_write_pending	=	0;
3659 	sk->sk_rcvlowat		=	1;
3660 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3661 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3662 
3663 	sk->sk_stamp = SK_DEFAULT_STAMP;
3664 #if BITS_PER_LONG==32
3665 	seqlock_init(&sk->sk_stamp_seq);
3666 #endif
3667 	atomic_set(&sk->sk_zckey, 0);
3668 
3669 #ifdef CONFIG_NET_RX_BUSY_POLL
3670 	sk->sk_napi_id		=	0;
3671 	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3672 #endif
3673 
3674 	sk->sk_max_pacing_rate = ~0UL;
3675 	sk->sk_pacing_rate = ~0UL;
3676 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3677 	sk->sk_incoming_cpu = -1;
3678 
3679 	sk_rx_queue_clear(sk);
3680 	/*
3681 	 * Before updating sk_refcnt, we must commit prior changes to memory
3682 	 * (Documentation/RCU/rculist_nulls.rst for details)
3683 	 */
3684 	smp_wmb();
3685 	refcount_set(&sk->sk_refcnt, 1);
3686 	atomic_set(&sk->sk_drops, 0);
3687 }
3688 EXPORT_SYMBOL(sock_init_data_uid);
3689 
3690 void sock_init_data(struct socket *sock, struct sock *sk)
3691 {
3692 	kuid_t uid = sock ?
3693 		SOCK_INODE(sock)->i_uid :
3694 		make_kuid(sock_net(sk)->user_ns, 0);
3695 
3696 	sock_init_data_uid(sock, sk, uid);
3697 }
3698 EXPORT_SYMBOL(sock_init_data);
3699 
3700 void lock_sock_nested(struct sock *sk, int subclass)
3701 {
3702 	/* The sk_lock has mutex_lock() semantics here. */
3703 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3704 
3705 	might_sleep();
3706 	spin_lock_bh(&sk->sk_lock.slock);
3707 	if (sock_owned_by_user_nocheck(sk))
3708 		__lock_sock(sk);
3709 	sk->sk_lock.owned = 1;
3710 	spin_unlock_bh(&sk->sk_lock.slock);
3711 }
3712 EXPORT_SYMBOL(lock_sock_nested);
3713 
3714 void release_sock(struct sock *sk)
3715 {
3716 	spin_lock_bh(&sk->sk_lock.slock);
3717 	if (sk->sk_backlog.tail)
3718 		__release_sock(sk);
3719 
3720 	if (sk->sk_prot->release_cb)
3721 		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3722 				     tcp_release_cb, sk);
3723 
3724 	sock_release_ownership(sk);
3725 	if (waitqueue_active(&sk->sk_lock.wq))
3726 		wake_up(&sk->sk_lock.wq);
3727 	spin_unlock_bh(&sk->sk_lock.slock);
3728 }
3729 EXPORT_SYMBOL(release_sock);
3730 
3731 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3732 {
3733 	might_sleep();
3734 	spin_lock_bh(&sk->sk_lock.slock);
3735 
3736 	if (!sock_owned_by_user_nocheck(sk)) {
3737 		/*
3738 		 * Fast path return with bottom halves disabled and
3739 		 * sock::sk_lock.slock held.
3740 		 *
3741 		 * The 'mutex' is not contended and holding
3742 		 * sock::sk_lock.slock prevents all other lockers to
3743 		 * proceed so the corresponding unlock_sock_fast() can
3744 		 * avoid the slow path of release_sock() completely and
3745 		 * just release slock.
3746 		 *
3747 		 * From a semantical POV this is equivalent to 'acquiring'
3748 		 * the 'mutex', hence the corresponding lockdep
3749 		 * mutex_release() has to happen in the fast path of
3750 		 * unlock_sock_fast().
3751 		 */
3752 		return false;
3753 	}
3754 
3755 	__lock_sock(sk);
3756 	sk->sk_lock.owned = 1;
3757 	__acquire(&sk->sk_lock.slock);
3758 	spin_unlock_bh(&sk->sk_lock.slock);
3759 	return true;
3760 }
3761 EXPORT_SYMBOL(__lock_sock_fast);
3762 
3763 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3764 		   bool timeval, bool time32)
3765 {
3766 	struct sock *sk = sock->sk;
3767 	struct timespec64 ts;
3768 
3769 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3770 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3771 	if (ts.tv_sec == -1)
3772 		return -ENOENT;
3773 	if (ts.tv_sec == 0) {
3774 		ktime_t kt = ktime_get_real();
3775 		sock_write_timestamp(sk, kt);
3776 		ts = ktime_to_timespec64(kt);
3777 	}
3778 
3779 	if (timeval)
3780 		ts.tv_nsec /= 1000;
3781 
3782 #ifdef CONFIG_COMPAT_32BIT_TIME
3783 	if (time32)
3784 		return put_old_timespec32(&ts, userstamp);
3785 #endif
3786 #ifdef CONFIG_SPARC64
3787 	/* beware of padding in sparc64 timeval */
3788 	if (timeval && !in_compat_syscall()) {
3789 		struct __kernel_old_timeval __user tv = {
3790 			.tv_sec = ts.tv_sec,
3791 			.tv_usec = ts.tv_nsec,
3792 		};
3793 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3794 			return -EFAULT;
3795 		return 0;
3796 	}
3797 #endif
3798 	return put_timespec64(&ts, userstamp);
3799 }
3800 EXPORT_SYMBOL(sock_gettstamp);
3801 
3802 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3803 {
3804 	if (!sock_flag(sk, flag)) {
3805 		unsigned long previous_flags = sk->sk_flags;
3806 
3807 		sock_set_flag(sk, flag);
3808 		/*
3809 		 * we just set one of the two flags which require net
3810 		 * time stamping, but time stamping might have been on
3811 		 * already because of the other one
3812 		 */
3813 		if (sock_needs_netstamp(sk) &&
3814 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3815 			net_enable_timestamp();
3816 	}
3817 }
3818 
3819 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3820 		       int level, int type)
3821 {
3822 	struct sock_exterr_skb *serr;
3823 	struct sk_buff *skb;
3824 	int copied, err;
3825 
3826 	err = -EAGAIN;
3827 	skb = sock_dequeue_err_skb(sk);
3828 	if (skb == NULL)
3829 		goto out;
3830 
3831 	copied = skb->len;
3832 	if (copied > len) {
3833 		msg->msg_flags |= MSG_TRUNC;
3834 		copied = len;
3835 	}
3836 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3837 	if (err)
3838 		goto out_free_skb;
3839 
3840 	sock_recv_timestamp(msg, sk, skb);
3841 
3842 	serr = SKB_EXT_ERR(skb);
3843 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3844 
3845 	msg->msg_flags |= MSG_ERRQUEUE;
3846 	err = copied;
3847 
3848 out_free_skb:
3849 	kfree_skb(skb);
3850 out:
3851 	return err;
3852 }
3853 EXPORT_SYMBOL(sock_recv_errqueue);
3854 
3855 /*
3856  *	Get a socket option on an socket.
3857  *
3858  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3859  *	asynchronous errors should be reported by getsockopt. We assume
3860  *	this means if you specify SO_ERROR (otherwise what is the point of it).
3861  */
3862 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3863 			   char __user *optval, int __user *optlen)
3864 {
3865 	struct sock *sk = sock->sk;
3866 
3867 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3868 	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3869 }
3870 EXPORT_SYMBOL(sock_common_getsockopt);
3871 
3872 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3873 			int flags)
3874 {
3875 	struct sock *sk = sock->sk;
3876 	int addr_len = 0;
3877 	int err;
3878 
3879 	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3880 	if (err >= 0)
3881 		msg->msg_namelen = addr_len;
3882 	return err;
3883 }
3884 EXPORT_SYMBOL(sock_common_recvmsg);
3885 
3886 /*
3887  *	Set socket options on an inet socket.
3888  */
3889 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3890 			   sockptr_t optval, unsigned int optlen)
3891 {
3892 	struct sock *sk = sock->sk;
3893 
3894 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3895 	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3896 }
3897 EXPORT_SYMBOL(sock_common_setsockopt);
3898 
3899 void sk_common_release(struct sock *sk)
3900 {
3901 	if (sk->sk_prot->destroy)
3902 		sk->sk_prot->destroy(sk);
3903 
3904 	/*
3905 	 * Observation: when sk_common_release is called, processes have
3906 	 * no access to socket. But net still has.
3907 	 * Step one, detach it from networking:
3908 	 *
3909 	 * A. Remove from hash tables.
3910 	 */
3911 
3912 	sk->sk_prot->unhash(sk);
3913 
3914 	/*
3915 	 * In this point socket cannot receive new packets, but it is possible
3916 	 * that some packets are in flight because some CPU runs receiver and
3917 	 * did hash table lookup before we unhashed socket. They will achieve
3918 	 * receive queue and will be purged by socket destructor.
3919 	 *
3920 	 * Also we still have packets pending on receive queue and probably,
3921 	 * our own packets waiting in device queues. sock_destroy will drain
3922 	 * receive queue, but transmitted packets will delay socket destruction
3923 	 * until the last reference will be released.
3924 	 */
3925 
3926 	sock_orphan(sk);
3927 
3928 	xfrm_sk_free_policy(sk);
3929 
3930 	sock_put(sk);
3931 }
3932 EXPORT_SYMBOL(sk_common_release);
3933 
3934 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3935 {
3936 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3937 
3938 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3939 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3940 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3941 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3942 	mem[SK_MEMINFO_FWD_ALLOC] = READ_ONCE(sk->sk_forward_alloc);
3943 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3944 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3945 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3946 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3947 }
3948 
3949 #ifdef CONFIG_PROC_FS
3950 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3951 
3952 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3953 {
3954 	int cpu, idx = prot->inuse_idx;
3955 	int res = 0;
3956 
3957 	for_each_possible_cpu(cpu)
3958 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3959 
3960 	return res >= 0 ? res : 0;
3961 }
3962 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3963 
3964 int sock_inuse_get(struct net *net)
3965 {
3966 	int cpu, res = 0;
3967 
3968 	for_each_possible_cpu(cpu)
3969 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3970 
3971 	return res;
3972 }
3973 
3974 EXPORT_SYMBOL_GPL(sock_inuse_get);
3975 
3976 static int __net_init sock_inuse_init_net(struct net *net)
3977 {
3978 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3979 	if (net->core.prot_inuse == NULL)
3980 		return -ENOMEM;
3981 	return 0;
3982 }
3983 
3984 static void __net_exit sock_inuse_exit_net(struct net *net)
3985 {
3986 	free_percpu(net->core.prot_inuse);
3987 }
3988 
3989 static struct pernet_operations net_inuse_ops = {
3990 	.init = sock_inuse_init_net,
3991 	.exit = sock_inuse_exit_net,
3992 };
3993 
3994 static __init int net_inuse_init(void)
3995 {
3996 	if (register_pernet_subsys(&net_inuse_ops))
3997 		panic("Cannot initialize net inuse counters");
3998 
3999 	return 0;
4000 }
4001 
4002 core_initcall(net_inuse_init);
4003 
4004 static int assign_proto_idx(struct proto *prot)
4005 {
4006 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
4007 
4008 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR)) {
4009 		pr_err("PROTO_INUSE_NR exhausted\n");
4010 		return -ENOSPC;
4011 	}
4012 
4013 	set_bit(prot->inuse_idx, proto_inuse_idx);
4014 	return 0;
4015 }
4016 
4017 static void release_proto_idx(struct proto *prot)
4018 {
4019 	if (prot->inuse_idx != PROTO_INUSE_NR)
4020 		clear_bit(prot->inuse_idx, proto_inuse_idx);
4021 }
4022 #else
4023 static inline int assign_proto_idx(struct proto *prot)
4024 {
4025 	return 0;
4026 }
4027 
4028 static inline void release_proto_idx(struct proto *prot)
4029 {
4030 }
4031 
4032 #endif
4033 
4034 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
4035 {
4036 	if (!twsk_prot)
4037 		return;
4038 	kfree(twsk_prot->twsk_slab_name);
4039 	twsk_prot->twsk_slab_name = NULL;
4040 	kmem_cache_destroy(twsk_prot->twsk_slab);
4041 	twsk_prot->twsk_slab = NULL;
4042 }
4043 
4044 static int tw_prot_init(const struct proto *prot)
4045 {
4046 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
4047 
4048 	if (!twsk_prot)
4049 		return 0;
4050 
4051 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
4052 					      prot->name);
4053 	if (!twsk_prot->twsk_slab_name)
4054 		return -ENOMEM;
4055 
4056 	twsk_prot->twsk_slab =
4057 		kmem_cache_create(twsk_prot->twsk_slab_name,
4058 				  twsk_prot->twsk_obj_size, 0,
4059 				  SLAB_ACCOUNT | prot->slab_flags,
4060 				  NULL);
4061 	if (!twsk_prot->twsk_slab) {
4062 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
4063 			prot->name);
4064 		return -ENOMEM;
4065 	}
4066 
4067 	return 0;
4068 }
4069 
4070 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
4071 {
4072 	if (!rsk_prot)
4073 		return;
4074 	kfree(rsk_prot->slab_name);
4075 	rsk_prot->slab_name = NULL;
4076 	kmem_cache_destroy(rsk_prot->slab);
4077 	rsk_prot->slab = NULL;
4078 }
4079 
4080 static int req_prot_init(const struct proto *prot)
4081 {
4082 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
4083 
4084 	if (!rsk_prot)
4085 		return 0;
4086 
4087 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
4088 					prot->name);
4089 	if (!rsk_prot->slab_name)
4090 		return -ENOMEM;
4091 
4092 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
4093 					   rsk_prot->obj_size, 0,
4094 					   SLAB_ACCOUNT | prot->slab_flags,
4095 					   NULL);
4096 
4097 	if (!rsk_prot->slab) {
4098 		pr_crit("%s: Can't create request sock SLAB cache!\n",
4099 			prot->name);
4100 		return -ENOMEM;
4101 	}
4102 	return 0;
4103 }
4104 
4105 int proto_register(struct proto *prot, int alloc_slab)
4106 {
4107 	int ret = -ENOBUFS;
4108 
4109 	if (prot->memory_allocated && !prot->sysctl_mem) {
4110 		pr_err("%s: missing sysctl_mem\n", prot->name);
4111 		return -EINVAL;
4112 	}
4113 	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
4114 		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
4115 		return -EINVAL;
4116 	}
4117 	if (alloc_slab) {
4118 		prot->slab = kmem_cache_create_usercopy(prot->name,
4119 					prot->obj_size, 0,
4120 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
4121 					prot->slab_flags,
4122 					prot->useroffset, prot->usersize,
4123 					NULL);
4124 
4125 		if (prot->slab == NULL) {
4126 			pr_crit("%s: Can't create sock SLAB cache!\n",
4127 				prot->name);
4128 			goto out;
4129 		}
4130 
4131 		if (req_prot_init(prot))
4132 			goto out_free_request_sock_slab;
4133 
4134 		if (tw_prot_init(prot))
4135 			goto out_free_timewait_sock_slab;
4136 	}
4137 
4138 	mutex_lock(&proto_list_mutex);
4139 	ret = assign_proto_idx(prot);
4140 	if (ret) {
4141 		mutex_unlock(&proto_list_mutex);
4142 		goto out_free_timewait_sock_slab;
4143 	}
4144 	list_add(&prot->node, &proto_list);
4145 	mutex_unlock(&proto_list_mutex);
4146 	return ret;
4147 
4148 out_free_timewait_sock_slab:
4149 	if (alloc_slab)
4150 		tw_prot_cleanup(prot->twsk_prot);
4151 out_free_request_sock_slab:
4152 	if (alloc_slab) {
4153 		req_prot_cleanup(prot->rsk_prot);
4154 
4155 		kmem_cache_destroy(prot->slab);
4156 		prot->slab = NULL;
4157 	}
4158 out:
4159 	return ret;
4160 }
4161 EXPORT_SYMBOL(proto_register);
4162 
4163 void proto_unregister(struct proto *prot)
4164 {
4165 	mutex_lock(&proto_list_mutex);
4166 	release_proto_idx(prot);
4167 	list_del(&prot->node);
4168 	mutex_unlock(&proto_list_mutex);
4169 
4170 	kmem_cache_destroy(prot->slab);
4171 	prot->slab = NULL;
4172 
4173 	req_prot_cleanup(prot->rsk_prot);
4174 	tw_prot_cleanup(prot->twsk_prot);
4175 }
4176 EXPORT_SYMBOL(proto_unregister);
4177 
4178 int sock_load_diag_module(int family, int protocol)
4179 {
4180 	if (!protocol) {
4181 		if (!sock_is_registered(family))
4182 			return -ENOENT;
4183 
4184 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4185 				      NETLINK_SOCK_DIAG, family);
4186 	}
4187 
4188 #ifdef CONFIG_INET
4189 	if (family == AF_INET &&
4190 	    protocol != IPPROTO_RAW &&
4191 	    protocol < MAX_INET_PROTOS &&
4192 	    !rcu_access_pointer(inet_protos[protocol]))
4193 		return -ENOENT;
4194 #endif
4195 
4196 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4197 			      NETLINK_SOCK_DIAG, family, protocol);
4198 }
4199 EXPORT_SYMBOL(sock_load_diag_module);
4200 
4201 #ifdef CONFIG_PROC_FS
4202 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4203 	__acquires(proto_list_mutex)
4204 {
4205 	mutex_lock(&proto_list_mutex);
4206 	return seq_list_start_head(&proto_list, *pos);
4207 }
4208 
4209 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4210 {
4211 	return seq_list_next(v, &proto_list, pos);
4212 }
4213 
4214 static void proto_seq_stop(struct seq_file *seq, void *v)
4215 	__releases(proto_list_mutex)
4216 {
4217 	mutex_unlock(&proto_list_mutex);
4218 }
4219 
4220 static char proto_method_implemented(const void *method)
4221 {
4222 	return method == NULL ? 'n' : 'y';
4223 }
4224 static long sock_prot_memory_allocated(struct proto *proto)
4225 {
4226 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4227 }
4228 
4229 static const char *sock_prot_memory_pressure(struct proto *proto)
4230 {
4231 	return proto->memory_pressure != NULL ?
4232 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4233 }
4234 
4235 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4236 {
4237 
4238 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4239 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4240 		   proto->name,
4241 		   proto->obj_size,
4242 		   sock_prot_inuse_get(seq_file_net(seq), proto),
4243 		   sock_prot_memory_allocated(proto),
4244 		   sock_prot_memory_pressure(proto),
4245 		   proto->max_header,
4246 		   proto->slab == NULL ? "no" : "yes",
4247 		   module_name(proto->owner),
4248 		   proto_method_implemented(proto->close),
4249 		   proto_method_implemented(proto->connect),
4250 		   proto_method_implemented(proto->disconnect),
4251 		   proto_method_implemented(proto->accept),
4252 		   proto_method_implemented(proto->ioctl),
4253 		   proto_method_implemented(proto->init),
4254 		   proto_method_implemented(proto->destroy),
4255 		   proto_method_implemented(proto->shutdown),
4256 		   proto_method_implemented(proto->setsockopt),
4257 		   proto_method_implemented(proto->getsockopt),
4258 		   proto_method_implemented(proto->sendmsg),
4259 		   proto_method_implemented(proto->recvmsg),
4260 		   proto_method_implemented(proto->bind),
4261 		   proto_method_implemented(proto->backlog_rcv),
4262 		   proto_method_implemented(proto->hash),
4263 		   proto_method_implemented(proto->unhash),
4264 		   proto_method_implemented(proto->get_port),
4265 		   proto_method_implemented(proto->enter_memory_pressure));
4266 }
4267 
4268 static int proto_seq_show(struct seq_file *seq, void *v)
4269 {
4270 	if (v == &proto_list)
4271 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4272 			   "protocol",
4273 			   "size",
4274 			   "sockets",
4275 			   "memory",
4276 			   "press",
4277 			   "maxhdr",
4278 			   "slab",
4279 			   "module",
4280 			   "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4281 	else
4282 		proto_seq_printf(seq, list_entry(v, struct proto, node));
4283 	return 0;
4284 }
4285 
4286 static const struct seq_operations proto_seq_ops = {
4287 	.start  = proto_seq_start,
4288 	.next   = proto_seq_next,
4289 	.stop   = proto_seq_stop,
4290 	.show   = proto_seq_show,
4291 };
4292 
4293 static __net_init int proto_init_net(struct net *net)
4294 {
4295 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4296 			sizeof(struct seq_net_private)))
4297 		return -ENOMEM;
4298 
4299 	return 0;
4300 }
4301 
4302 static __net_exit void proto_exit_net(struct net *net)
4303 {
4304 	remove_proc_entry("protocols", net->proc_net);
4305 }
4306 
4307 
4308 static __net_initdata struct pernet_operations proto_net_ops = {
4309 	.init = proto_init_net,
4310 	.exit = proto_exit_net,
4311 };
4312 
4313 static int __init proto_init(void)
4314 {
4315 	return register_pernet_subsys(&proto_net_ops);
4316 }
4317 
4318 subsys_initcall(proto_init);
4319 
4320 #endif /* PROC_FS */
4321 
4322 #ifdef CONFIG_NET_RX_BUSY_POLL
4323 bool sk_busy_loop_end(void *p, unsigned long start_time)
4324 {
4325 	struct sock *sk = p;
4326 
4327 	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4328 		return true;
4329 
4330 	if (sk_is_udp(sk) &&
4331 	    !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4332 		return true;
4333 
4334 	return sk_busy_loop_timeout(sk, start_time);
4335 }
4336 EXPORT_SYMBOL(sk_busy_loop_end);
4337 #endif /* CONFIG_NET_RX_BUSY_POLL */
4338 
4339 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4340 {
4341 	if (!sk->sk_prot->bind_add)
4342 		return -EOPNOTSUPP;
4343 	return sk->sk_prot->bind_add(sk, addr, addr_len);
4344 }
4345 EXPORT_SYMBOL(sock_bind_add);
4346 
4347 /* Copy 'size' bytes from userspace and return `size` back to userspace */
4348 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4349 		     void __user *arg, void *karg, size_t size)
4350 {
4351 	int ret;
4352 
4353 	if (copy_from_user(karg, arg, size))
4354 		return -EFAULT;
4355 
4356 	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4357 	if (ret)
4358 		return ret;
4359 
4360 	if (copy_to_user(arg, karg, size))
4361 		return -EFAULT;
4362 
4363 	return 0;
4364 }
4365 EXPORT_SYMBOL(sock_ioctl_inout);
4366 
4367 /* This is the most common ioctl prep function, where the result (4 bytes) is
4368  * copied back to userspace if the ioctl() returns successfully. No input is
4369  * copied from userspace as input argument.
4370  */
4371 static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4372 {
4373 	int ret, karg = 0;
4374 
4375 	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4376 	if (ret)
4377 		return ret;
4378 
4379 	return put_user(karg, (int __user *)arg);
4380 }
4381 
4382 /* A wrapper around sock ioctls, which copies the data from userspace
4383  * (depending on the protocol/ioctl), and copies back the result to userspace.
4384  * The main motivation for this function is to pass kernel memory to the
4385  * protocol ioctl callbacks, instead of userspace memory.
4386  */
4387 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4388 {
4389 	int rc = 1;
4390 
4391 	if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4392 		rc = ipmr_sk_ioctl(sk, cmd, arg);
4393 	else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4394 		rc = ip6mr_sk_ioctl(sk, cmd, arg);
4395 	else if (sk_is_phonet(sk))
4396 		rc = phonet_sk_ioctl(sk, cmd, arg);
4397 
4398 	/* If ioctl was processed, returns its value */
4399 	if (rc <= 0)
4400 		return rc;
4401 
4402 	/* Otherwise call the default handler */
4403 	return sock_ioctl_out(sk, cmd, arg);
4404 }
4405 EXPORT_SYMBOL(sk_ioctl);
4406 
4407 static int __init sock_struct_check(void)
4408 {
4409 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_drops);
4410 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_peek_off);
4411 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_error_queue);
4412 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_receive_queue);
4413 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_backlog);
4414 
4415 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst);
4416 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_ifindex);
4417 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_cookie);
4418 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvbuf);
4419 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_filter);
4420 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_wq);
4421 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_data_ready);
4422 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvtimeo);
4423 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvlowat);
4424 
4425 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_err);
4426 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_socket);
4427 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_memcg);
4428 
4429 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_lock);
4430 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_reserved_mem);
4431 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_forward_alloc);
4432 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_tsflags);
4433 
4434 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4435 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4436 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_sndbuf);
4437 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_queued);
4438 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_alloc);
4439 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tsq_flags);
4440 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_send_head);
4441 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_queue);
4442 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_pending);
4443 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_dst_pending_confirm);
4444 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_status);
4445 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_frag);
4446 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_timer);
4447 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_rate);
4448 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_zckey);
4449 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tskey);
4450 
4451 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_max_pacing_rate);
4452 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndtimeo);
4453 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_priority);
4454 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_mark);
4455 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_cache);
4456 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_route_caps);
4457 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_type);
4458 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_size);
4459 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_allocation);
4460 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_txhash);
4461 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_segs);
4462 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_shift);
4463 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_use_task_frag);
4464 	return 0;
4465 }
4466 
4467 core_initcall(sock_struct_check);
4468