xref: /linux/net/core/sock.c (revision 26ba30221c03364d6ed9910be8da4c1fd871b07b)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * INET		An implementation of the TCP/IP protocol suite for the LINUX
4  *		operating system.  INET is implemented using the  BSD Socket
5  *		interface as the means of communication with the user level.
6  *
7  *		Generic socket support routines. Memory allocators, socket lock/release
8  *		handler for protocols to use and generic option handler.
9  *
10  * Authors:	Ross Biro
11  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12  *		Florian La Roche, <flla@stud.uni-sb.de>
13  *		Alan Cox, <A.Cox@swansea.ac.uk>
14  *
15  * Fixes:
16  *		Alan Cox	: 	Numerous verify_area() problems
17  *		Alan Cox	:	Connecting on a connecting socket
18  *					now returns an error for tcp.
19  *		Alan Cox	:	sock->protocol is set correctly.
20  *					and is not sometimes left as 0.
21  *		Alan Cox	:	connect handles icmp errors on a
22  *					connect properly. Unfortunately there
23  *					is a restart syscall nasty there. I
24  *					can't match BSD without hacking the C
25  *					library. Ideas urgently sought!
26  *		Alan Cox	:	Disallow bind() to addresses that are
27  *					not ours - especially broadcast ones!!
28  *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
29  *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
30  *					instead they leave that for the DESTROY timer.
31  *		Alan Cox	:	Clean up error flag in accept
32  *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
33  *					was buggy. Put a remove_sock() in the handler
34  *					for memory when we hit 0. Also altered the timer
35  *					code. The ACK stuff can wait and needs major
36  *					TCP layer surgery.
37  *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
38  *					and fixed timer/inet_bh race.
39  *		Alan Cox	:	Added zapped flag for TCP
40  *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
41  *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42  *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
43  *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
44  *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45  *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
46  *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
47  *	Pauline Middelink	:	identd support
48  *		Alan Cox	:	Fixed connect() taking signals I think.
49  *		Alan Cox	:	SO_LINGER supported
50  *		Alan Cox	:	Error reporting fixes
51  *		Anonymous	:	inet_create tidied up (sk->reuse setting)
52  *		Alan Cox	:	inet sockets don't set sk->type!
53  *		Alan Cox	:	Split socket option code
54  *		Alan Cox	:	Callbacks
55  *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
56  *		Alex		:	Removed restriction on inet fioctl
57  *		Alan Cox	:	Splitting INET from NET core
58  *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
59  *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
60  *		Alan Cox	:	Split IP from generic code
61  *		Alan Cox	:	New kfree_skbmem()
62  *		Alan Cox	:	Make SO_DEBUG superuser only.
63  *		Alan Cox	:	Allow anyone to clear SO_DEBUG
64  *					(compatibility fix)
65  *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
66  *		Alan Cox	:	Allocator for a socket is settable.
67  *		Alan Cox	:	SO_ERROR includes soft errors.
68  *		Alan Cox	:	Allow NULL arguments on some SO_ opts
69  *		Alan Cox	: 	Generic socket allocation to make hooks
70  *					easier (suggested by Craig Metz).
71  *		Michael Pall	:	SO_ERROR returns positive errno again
72  *              Steve Whitehouse:       Added default destructor to free
73  *                                      protocol private data.
74  *              Steve Whitehouse:       Added various other default routines
75  *                                      common to several socket families.
76  *              Chris Evans     :       Call suser() check last on F_SETOWN
77  *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78  *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
79  *		Andi Kleen	:	Fix write_space callback
80  *		Chris Evans	:	Security fixes - signedness again
81  *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
82  *
83  * To Fix:
84  */
85 
86 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
87 
88 #include <linux/unaligned.h>
89 #include <linux/capability.h>
90 #include <linux/errno.h>
91 #include <linux/errqueue.h>
92 #include <linux/types.h>
93 #include <linux/socket.h>
94 #include <linux/in.h>
95 #include <linux/kernel.h>
96 #include <linux/module.h>
97 #include <linux/proc_fs.h>
98 #include <linux/seq_file.h>
99 #include <linux/sched.h>
100 #include <linux/sched/mm.h>
101 #include <linux/timer.h>
102 #include <linux/string.h>
103 #include <linux/sockios.h>
104 #include <linux/net.h>
105 #include <linux/mm.h>
106 #include <linux/slab.h>
107 #include <linux/interrupt.h>
108 #include <linux/poll.h>
109 #include <linux/tcp.h>
110 #include <linux/udp.h>
111 #include <linux/init.h>
112 #include <linux/highmem.h>
113 #include <linux/user_namespace.h>
114 #include <linux/static_key.h>
115 #include <linux/memcontrol.h>
116 #include <linux/prefetch.h>
117 #include <linux/compat.h>
118 #include <linux/mroute.h>
119 #include <linux/mroute6.h>
120 #include <linux/icmpv6.h>
121 
122 #include <linux/uaccess.h>
123 
124 #include <linux/netdevice.h>
125 #include <net/protocol.h>
126 #include <linux/skbuff.h>
127 #include <linux/skbuff_ref.h>
128 #include <net/net_namespace.h>
129 #include <net/request_sock.h>
130 #include <net/sock.h>
131 #include <net/proto_memory.h>
132 #include <linux/net_tstamp.h>
133 #include <net/xfrm.h>
134 #include <linux/ipsec.h>
135 #include <net/cls_cgroup.h>
136 #include <net/netprio_cgroup.h>
137 #include <linux/sock_diag.h>
138 
139 #include <linux/filter.h>
140 #include <net/sock_reuseport.h>
141 #include <net/bpf_sk_storage.h>
142 
143 #include <trace/events/sock.h>
144 
145 #include <net/tcp.h>
146 #include <net/busy_poll.h>
147 #include <net/phonet/phonet.h>
148 
149 #include <linux/ethtool.h>
150 
151 #include <uapi/linux/pidfd.h>
152 
153 #include "dev.h"
154 
155 static DEFINE_MUTEX(proto_list_mutex);
156 static LIST_HEAD(proto_list);
157 
158 static void sock_def_write_space_wfree(struct sock *sk, int wmem_alloc);
159 static void sock_def_write_space(struct sock *sk);
160 
161 /**
162  * sk_ns_capable - General socket capability test
163  * @sk: Socket to use a capability on or through
164  * @user_ns: The user namespace of the capability to use
165  * @cap: The capability to use
166  *
167  * Test to see if the opener of the socket had when the socket was
168  * created and the current process has the capability @cap in the user
169  * namespace @user_ns.
170  */
171 bool sk_ns_capable(const struct sock *sk,
172 		   struct user_namespace *user_ns, int cap)
173 {
174 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
175 		ns_capable(user_ns, cap);
176 }
177 EXPORT_SYMBOL(sk_ns_capable);
178 
179 /**
180  * sk_capable - Socket global capability test
181  * @sk: Socket to use a capability on or through
182  * @cap: The global capability to use
183  *
184  * Test to see if the opener of the socket had when the socket was
185  * created and the current process has the capability @cap in all user
186  * namespaces.
187  */
188 bool sk_capable(const struct sock *sk, int cap)
189 {
190 	return sk_ns_capable(sk, &init_user_ns, cap);
191 }
192 EXPORT_SYMBOL(sk_capable);
193 
194 /**
195  * sk_net_capable - Network namespace socket capability test
196  * @sk: Socket to use a capability on or through
197  * @cap: The capability to use
198  *
199  * Test to see if the opener of the socket had when the socket was created
200  * and the current process has the capability @cap over the network namespace
201  * the socket is a member of.
202  */
203 bool sk_net_capable(const struct sock *sk, int cap)
204 {
205 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
206 }
207 EXPORT_SYMBOL(sk_net_capable);
208 
209 /*
210  * Each address family might have different locking rules, so we have
211  * one slock key per address family and separate keys for internal and
212  * userspace sockets.
213  */
214 static struct lock_class_key af_family_keys[AF_MAX];
215 static struct lock_class_key af_family_kern_keys[AF_MAX];
216 static struct lock_class_key af_family_slock_keys[AF_MAX];
217 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
218 
219 /*
220  * Make lock validator output more readable. (we pre-construct these
221  * strings build-time, so that runtime initialization of socket
222  * locks is fast):
223  */
224 
225 #define _sock_locks(x)						  \
226   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
227   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
228   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
229   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
230   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
231   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
232   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
233   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
234   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
235   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
236   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
237   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
238   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
239   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
240   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
241   x "AF_MCTP"  , \
242   x "AF_MAX"
243 
244 static const char *const af_family_key_strings[AF_MAX+1] = {
245 	_sock_locks("sk_lock-")
246 };
247 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
248 	_sock_locks("slock-")
249 };
250 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
251 	_sock_locks("clock-")
252 };
253 
254 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
255 	_sock_locks("k-sk_lock-")
256 };
257 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
258 	_sock_locks("k-slock-")
259 };
260 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
261 	_sock_locks("k-clock-")
262 };
263 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
264 	_sock_locks("rlock-")
265 };
266 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
267 	_sock_locks("wlock-")
268 };
269 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
270 	_sock_locks("elock-")
271 };
272 
273 /*
274  * sk_callback_lock and sk queues locking rules are per-address-family,
275  * so split the lock classes by using a per-AF key:
276  */
277 static struct lock_class_key af_callback_keys[AF_MAX];
278 static struct lock_class_key af_rlock_keys[AF_MAX];
279 static struct lock_class_key af_wlock_keys[AF_MAX];
280 static struct lock_class_key af_elock_keys[AF_MAX];
281 static struct lock_class_key af_kern_callback_keys[AF_MAX];
282 
283 /* Run time adjustable parameters. */
284 __u32 sysctl_wmem_max __read_mostly = 4 << 20;
285 EXPORT_SYMBOL(sysctl_wmem_max);
286 __u32 sysctl_rmem_max __read_mostly = 4 << 20;
287 EXPORT_SYMBOL(sysctl_rmem_max);
288 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_DEFAULT;
289 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_DEFAULT;
290 
291 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
292 EXPORT_SYMBOL_GPL(memalloc_socks_key);
293 
294 /**
295  * sk_set_memalloc - sets %SOCK_MEMALLOC
296  * @sk: socket to set it on
297  *
298  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
299  * It's the responsibility of the admin to adjust min_free_kbytes
300  * to meet the requirements
301  */
302 void sk_set_memalloc(struct sock *sk)
303 {
304 	sock_set_flag(sk, SOCK_MEMALLOC);
305 	sk->sk_allocation |= __GFP_MEMALLOC;
306 	static_branch_inc(&memalloc_socks_key);
307 }
308 EXPORT_SYMBOL_GPL(sk_set_memalloc);
309 
310 void sk_clear_memalloc(struct sock *sk)
311 {
312 	sock_reset_flag(sk, SOCK_MEMALLOC);
313 	sk->sk_allocation &= ~__GFP_MEMALLOC;
314 	static_branch_dec(&memalloc_socks_key);
315 
316 	/*
317 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
318 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
319 	 * it has rmem allocations due to the last swapfile being deactivated
320 	 * but there is a risk that the socket is unusable due to exceeding
321 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
322 	 */
323 	sk_mem_reclaim(sk);
324 }
325 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
326 
327 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
328 {
329 	int ret;
330 	unsigned int noreclaim_flag;
331 
332 	/* these should have been dropped before queueing */
333 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
334 
335 	noreclaim_flag = memalloc_noreclaim_save();
336 	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
337 				 tcp_v6_do_rcv,
338 				 tcp_v4_do_rcv,
339 				 sk, skb);
340 	memalloc_noreclaim_restore(noreclaim_flag);
341 
342 	return ret;
343 }
344 EXPORT_SYMBOL(__sk_backlog_rcv);
345 
346 void sk_error_report(struct sock *sk)
347 {
348 	sk->sk_error_report(sk);
349 
350 	switch (sk->sk_family) {
351 	case AF_INET:
352 		fallthrough;
353 	case AF_INET6:
354 		trace_inet_sk_error_report(sk);
355 		break;
356 	default:
357 		break;
358 	}
359 }
360 EXPORT_SYMBOL(sk_error_report);
361 
362 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
363 {
364 	struct __kernel_sock_timeval tv;
365 
366 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
367 		tv.tv_sec = 0;
368 		tv.tv_usec = 0;
369 	} else {
370 		tv.tv_sec = timeo / HZ;
371 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
372 	}
373 
374 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
375 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
376 		*(struct old_timeval32 *)optval = tv32;
377 		return sizeof(tv32);
378 	}
379 
380 	if (old_timeval) {
381 		struct __kernel_old_timeval old_tv;
382 		old_tv.tv_sec = tv.tv_sec;
383 		old_tv.tv_usec = tv.tv_usec;
384 		*(struct __kernel_old_timeval *)optval = old_tv;
385 		return sizeof(old_tv);
386 	}
387 
388 	*(struct __kernel_sock_timeval *)optval = tv;
389 	return sizeof(tv);
390 }
391 EXPORT_SYMBOL(sock_get_timeout);
392 
393 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
394 			   sockptr_t optval, int optlen, bool old_timeval)
395 {
396 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
397 		struct old_timeval32 tv32;
398 
399 		if (optlen < sizeof(tv32))
400 			return -EINVAL;
401 
402 		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
403 			return -EFAULT;
404 		tv->tv_sec = tv32.tv_sec;
405 		tv->tv_usec = tv32.tv_usec;
406 	} else if (old_timeval) {
407 		struct __kernel_old_timeval old_tv;
408 
409 		if (optlen < sizeof(old_tv))
410 			return -EINVAL;
411 		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
412 			return -EFAULT;
413 		tv->tv_sec = old_tv.tv_sec;
414 		tv->tv_usec = old_tv.tv_usec;
415 	} else {
416 		if (optlen < sizeof(*tv))
417 			return -EINVAL;
418 		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
419 			return -EFAULT;
420 	}
421 
422 	return 0;
423 }
424 EXPORT_SYMBOL(sock_copy_user_timeval);
425 
426 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
427 			    bool old_timeval)
428 {
429 	struct __kernel_sock_timeval tv;
430 	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
431 	long val;
432 
433 	if (err)
434 		return err;
435 
436 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
437 		return -EDOM;
438 
439 	if (tv.tv_sec < 0) {
440 		static int warned __read_mostly;
441 
442 		WRITE_ONCE(*timeo_p, 0);
443 		if (warned < 10 && net_ratelimit()) {
444 			warned++;
445 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
446 				__func__, current->comm, task_pid_nr(current));
447 		}
448 		return 0;
449 	}
450 	val = MAX_SCHEDULE_TIMEOUT;
451 	if ((tv.tv_sec || tv.tv_usec) &&
452 	    (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))
453 		val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,
454 						    USEC_PER_SEC / HZ);
455 	WRITE_ONCE(*timeo_p, val);
456 	return 0;
457 }
458 
459 static bool sk_set_prio_allowed(const struct sock *sk, int val)
460 {
461 	return ((val >= TC_PRIO_BESTEFFORT && val <= TC_PRIO_INTERACTIVE) ||
462 		sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
463 		sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN));
464 }
465 
466 static bool sock_needs_netstamp(const struct sock *sk)
467 {
468 	switch (sk->sk_family) {
469 	case AF_UNSPEC:
470 	case AF_UNIX:
471 		return false;
472 	default:
473 		return true;
474 	}
475 }
476 
477 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
478 {
479 	if (sk->sk_flags & flags) {
480 		sk->sk_flags &= ~flags;
481 		if (sock_needs_netstamp(sk) &&
482 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
483 			net_disable_timestamp();
484 	}
485 }
486 
487 
488 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
489 {
490 	unsigned long flags;
491 	struct sk_buff_head *list = &sk->sk_receive_queue;
492 
493 	if (atomic_read(&sk->sk_rmem_alloc) >= READ_ONCE(sk->sk_rcvbuf)) {
494 		sk_drops_inc(sk);
495 		trace_sock_rcvqueue_full(sk, skb);
496 		return -ENOMEM;
497 	}
498 
499 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
500 		sk_drops_inc(sk);
501 		return -ENOBUFS;
502 	}
503 
504 	skb->dev = NULL;
505 	skb_set_owner_r(skb, sk);
506 
507 	/* we escape from rcu protected region, make sure we dont leak
508 	 * a norefcounted dst
509 	 */
510 	skb_dst_force(skb);
511 
512 	spin_lock_irqsave(&list->lock, flags);
513 	sock_skb_set_dropcount(sk, skb);
514 	__skb_queue_tail(list, skb);
515 	spin_unlock_irqrestore(&list->lock, flags);
516 
517 	if (!sock_flag(sk, SOCK_DEAD))
518 		sk->sk_data_ready(sk);
519 	return 0;
520 }
521 EXPORT_SYMBOL(__sock_queue_rcv_skb);
522 
523 enum skb_drop_reason
524 sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb)
525 {
526 	enum skb_drop_reason drop_reason;
527 	int err;
528 
529 	drop_reason = sk_filter_reason(sk, skb);
530 	if (drop_reason)
531 		return drop_reason;
532 
533 	err = __sock_queue_rcv_skb(sk, skb);
534 	switch (err) {
535 	case -ENOMEM:
536 		return SKB_DROP_REASON_SOCKET_RCVBUFF;
537 	case -ENOBUFS:
538 		return SKB_DROP_REASON_PROTO_MEM;
539 	}
540 	return SKB_NOT_DROPPED_YET;
541 }
542 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
543 
544 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
545 		     const int nested, unsigned int trim_cap, bool refcounted)
546 {
547 	enum skb_drop_reason reason;
548 	int rc = NET_RX_SUCCESS;
549 	int err;
550 
551 	reason = sk_filter_trim_cap(sk, skb, trim_cap);
552 	if (reason)
553 		goto discard_and_relse;
554 
555 	skb->dev = NULL;
556 
557 	if (sk_rcvqueues_full(sk, READ_ONCE(sk->sk_rcvbuf))) {
558 		sk_drops_inc(sk);
559 		reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
560 		goto discard_and_relse;
561 	}
562 	if (nested)
563 		bh_lock_sock_nested(sk);
564 	else
565 		bh_lock_sock(sk);
566 	if (!sock_owned_by_user(sk)) {
567 		/*
568 		 * trylock + unlock semantics:
569 		 */
570 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
571 
572 		rc = sk_backlog_rcv(sk, skb);
573 
574 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
575 	} else if ((err = sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf)))) {
576 		bh_unlock_sock(sk);
577 		if (err == -ENOMEM)
578 			reason = SKB_DROP_REASON_PFMEMALLOC;
579 		if (err == -ENOBUFS)
580 			reason = SKB_DROP_REASON_SOCKET_BACKLOG;
581 		sk_drops_inc(sk);
582 		goto discard_and_relse;
583 	}
584 
585 	bh_unlock_sock(sk);
586 out:
587 	if (refcounted)
588 		sock_put(sk);
589 	return rc;
590 discard_and_relse:
591 	sk_skb_reason_drop(sk, skb, reason);
592 	goto out;
593 }
594 EXPORT_SYMBOL(__sk_receive_skb);
595 
596 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
597 							  u32));
598 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
599 							   u32));
600 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
601 {
602 	struct dst_entry *dst = __sk_dst_get(sk);
603 
604 	if (dst && READ_ONCE(dst->obsolete) &&
605 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
606 			       dst, cookie) == NULL) {
607 		sk_tx_queue_clear(sk);
608 		WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
609 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
610 		dst_release(dst);
611 		return NULL;
612 	}
613 
614 	return dst;
615 }
616 EXPORT_SYMBOL(__sk_dst_check);
617 
618 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
619 {
620 	struct dst_entry *dst = sk_dst_get(sk);
621 
622 	if (dst && READ_ONCE(dst->obsolete) &&
623 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
624 			       dst, cookie) == NULL) {
625 		sk_dst_reset(sk);
626 		dst_release(dst);
627 		return NULL;
628 	}
629 
630 	return dst;
631 }
632 EXPORT_SYMBOL(sk_dst_check);
633 
634 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
635 {
636 	int ret = -ENOPROTOOPT;
637 #ifdef CONFIG_NETDEVICES
638 	struct net *net = sock_net(sk);
639 
640 	/* Sorry... */
641 	ret = -EPERM;
642 	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
643 		goto out;
644 
645 	ret = -EINVAL;
646 	if (ifindex < 0)
647 		goto out;
648 
649 	/* Paired with all READ_ONCE() done locklessly. */
650 	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
651 
652 	if (sk->sk_prot->rehash)
653 		sk->sk_prot->rehash(sk);
654 	sk_dst_reset(sk);
655 
656 	ret = 0;
657 
658 out:
659 #endif
660 
661 	return ret;
662 }
663 
664 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
665 {
666 	int ret;
667 
668 	if (lock_sk)
669 		lock_sock(sk);
670 	ret = sock_bindtoindex_locked(sk, ifindex);
671 	if (lock_sk)
672 		release_sock(sk);
673 
674 	return ret;
675 }
676 EXPORT_SYMBOL(sock_bindtoindex);
677 
678 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
679 {
680 	int ret = -ENOPROTOOPT;
681 #ifdef CONFIG_NETDEVICES
682 	struct net *net = sock_net(sk);
683 	char devname[IFNAMSIZ];
684 	int index;
685 
686 	ret = -EINVAL;
687 	if (optlen < 0)
688 		goto out;
689 
690 	/* Bind this socket to a particular device like "eth0",
691 	 * as specified in the passed interface name. If the
692 	 * name is "" or the option length is zero the socket
693 	 * is not bound.
694 	 */
695 	if (optlen > IFNAMSIZ - 1)
696 		optlen = IFNAMSIZ - 1;
697 	memset(devname, 0, sizeof(devname));
698 
699 	ret = -EFAULT;
700 	if (copy_from_sockptr(devname, optval, optlen))
701 		goto out;
702 
703 	index = 0;
704 	if (devname[0] != '\0') {
705 		struct net_device *dev;
706 
707 		rcu_read_lock();
708 		dev = dev_get_by_name_rcu(net, devname);
709 		if (dev)
710 			index = dev->ifindex;
711 		rcu_read_unlock();
712 		ret = -ENODEV;
713 		if (!dev)
714 			goto out;
715 	}
716 
717 	sockopt_lock_sock(sk);
718 	ret = sock_bindtoindex_locked(sk, index);
719 	sockopt_release_sock(sk);
720 out:
721 #endif
722 
723 	return ret;
724 }
725 
726 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
727 				sockptr_t optlen, int len)
728 {
729 	int ret = -ENOPROTOOPT;
730 #ifdef CONFIG_NETDEVICES
731 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
732 	struct net *net = sock_net(sk);
733 	char devname[IFNAMSIZ];
734 
735 	if (bound_dev_if == 0) {
736 		len = 0;
737 		goto zero;
738 	}
739 
740 	ret = -EINVAL;
741 	if (len < IFNAMSIZ)
742 		goto out;
743 
744 	ret = netdev_get_name(net, devname, bound_dev_if);
745 	if (ret)
746 		goto out;
747 
748 	len = strlen(devname) + 1;
749 
750 	ret = -EFAULT;
751 	if (copy_to_sockptr(optval, devname, len))
752 		goto out;
753 
754 zero:
755 	ret = -EFAULT;
756 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
757 		goto out;
758 
759 	ret = 0;
760 
761 out:
762 #endif
763 
764 	return ret;
765 }
766 
767 bool sk_mc_loop(const struct sock *sk)
768 {
769 	if (dev_recursion_level())
770 		return false;
771 	if (!sk)
772 		return true;
773 	/* IPV6_ADDRFORM can change sk->sk_family under us. */
774 	switch (READ_ONCE(sk->sk_family)) {
775 	case AF_INET:
776 		return inet_test_bit(MC_LOOP, sk);
777 #if IS_ENABLED(CONFIG_IPV6)
778 	case AF_INET6:
779 		return inet6_test_bit(MC6_LOOP, sk);
780 #endif
781 	}
782 	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 	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
820 		WRITE_ONCE(sk->sk_sndtimeo, secs * HZ);
821 	else
822 		WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT);
823 }
824 EXPORT_SYMBOL(sock_set_sndtimeo);
825 
826 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
827 {
828 	sock_valbool_flag(sk, SOCK_RCVTSTAMP, val);
829 	sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, val && ns);
830 	if (val)  {
831 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
832 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
833 	}
834 }
835 
836 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
837 {
838 	switch (optname) {
839 	case SO_TIMESTAMP_OLD:
840 		__sock_set_timestamps(sk, valbool, false, false);
841 		break;
842 	case SO_TIMESTAMP_NEW:
843 		__sock_set_timestamps(sk, valbool, true, false);
844 		break;
845 	case SO_TIMESTAMPNS_OLD:
846 		__sock_set_timestamps(sk, valbool, false, true);
847 		break;
848 	case SO_TIMESTAMPNS_NEW:
849 		__sock_set_timestamps(sk, valbool, true, true);
850 		break;
851 	}
852 }
853 
854 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
855 {
856 	struct net *net = sock_net(sk);
857 	struct net_device *dev = NULL;
858 	bool match = false;
859 	int *vclock_index;
860 	int i, num;
861 
862 	if (sk->sk_bound_dev_if)
863 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
864 
865 	if (!dev) {
866 		pr_err("%s: sock not bind to device\n", __func__);
867 		return -EOPNOTSUPP;
868 	}
869 
870 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
871 	dev_put(dev);
872 
873 	for (i = 0; i < num; i++) {
874 		if (*(vclock_index + i) == phc_index) {
875 			match = true;
876 			break;
877 		}
878 	}
879 
880 	if (num > 0)
881 		kfree(vclock_index);
882 
883 	if (!match)
884 		return -EINVAL;
885 
886 	WRITE_ONCE(sk->sk_bind_phc, phc_index);
887 
888 	return 0;
889 }
890 
891 int sock_set_timestamping(struct sock *sk, int optname,
892 			  struct so_timestamping timestamping)
893 {
894 	int val = timestamping.flags;
895 	int ret;
896 
897 	if (val & ~SOF_TIMESTAMPING_MASK)
898 		return -EINVAL;
899 
900 	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
901 	    !(val & SOF_TIMESTAMPING_OPT_ID))
902 		return -EINVAL;
903 
904 	if (val & SOF_TIMESTAMPING_OPT_ID &&
905 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
906 		if (sk_is_tcp(sk)) {
907 			if ((1 << sk->sk_state) &
908 			    (TCPF_CLOSE | TCPF_LISTEN))
909 				return -EINVAL;
910 			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
911 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
912 			else
913 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
914 		} else {
915 			atomic_set(&sk->sk_tskey, 0);
916 		}
917 	}
918 
919 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
920 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
921 		return -EINVAL;
922 
923 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
924 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
925 		if (ret)
926 			return ret;
927 	}
928 
929 	WRITE_ONCE(sk->sk_tsflags, val);
930 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
931 	sock_valbool_flag(sk, SOCK_TIMESTAMPING_ANY, !!(val & TSFLAGS_ANY));
932 
933 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
934 		sock_enable_timestamp(sk,
935 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
936 	else
937 		sock_disable_timestamp(sk,
938 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
939 	return 0;
940 }
941 
942 #if defined(CONFIG_CGROUP_BPF)
943 void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op)
944 {
945 	struct bpf_sock_ops_kern sock_ops;
946 
947 	memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp));
948 	sock_ops.op = op;
949 	sock_ops.is_fullsock = 1;
950 	sock_ops.sk = sk;
951 	bpf_skops_init_skb(&sock_ops, skb, 0);
952 	__cgroup_bpf_run_filter_sock_ops(sk, &sock_ops, CGROUP_SOCK_OPS);
953 }
954 #endif
955 
956 void sock_set_keepalive(struct sock *sk)
957 {
958 	lock_sock(sk);
959 	if (sk->sk_prot->keepalive)
960 		sk->sk_prot->keepalive(sk, true);
961 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
962 	release_sock(sk);
963 }
964 EXPORT_SYMBOL(sock_set_keepalive);
965 
966 static void __sock_set_rcvbuf(struct sock *sk, int val)
967 {
968 	struct socket *sock = sk->sk_socket;
969 
970 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
971 	 * as a negative value.
972 	 */
973 	val = min_t(int, val, INT_MAX / 2);
974 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
975 
976 	/* We double it on the way in to account for "struct sk_buff" etc.
977 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
978 	 * will allow that much actual data to be received on that socket.
979 	 *
980 	 * Applications are unaware that "struct sk_buff" and other overheads
981 	 * allocate from the receive buffer during socket buffer allocation.
982 	 *
983 	 * And after considering the possible alternatives, returning the value
984 	 * we actually used in getsockopt is the most desirable behavior.
985 	 */
986 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
987 
988 	if (sock) {
989 		const struct proto_ops *ops = READ_ONCE(sock->ops);
990 
991 		if (ops->set_rcvbuf)
992 			ops->set_rcvbuf(sk, sk->sk_rcvbuf);
993 	}
994 }
995 
996 void sock_set_rcvbuf(struct sock *sk, int val)
997 {
998 	lock_sock(sk);
999 	__sock_set_rcvbuf(sk, val);
1000 	release_sock(sk);
1001 }
1002 EXPORT_SYMBOL(sock_set_rcvbuf);
1003 
1004 static void __sock_set_mark(struct sock *sk, u32 val)
1005 {
1006 	if (val != sk->sk_mark) {
1007 		WRITE_ONCE(sk->sk_mark, val);
1008 		sk_dst_reset(sk);
1009 	}
1010 }
1011 
1012 void sock_set_mark(struct sock *sk, u32 val)
1013 {
1014 	lock_sock(sk);
1015 	__sock_set_mark(sk, val);
1016 	release_sock(sk);
1017 }
1018 EXPORT_SYMBOL(sock_set_mark);
1019 
1020 static void sock_release_reserved_memory(struct sock *sk, int bytes)
1021 {
1022 	/* Round down bytes to multiple of pages */
1023 	bytes = round_down(bytes, PAGE_SIZE);
1024 
1025 	WARN_ON(bytes > sk->sk_reserved_mem);
1026 	WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes);
1027 	sk_mem_reclaim(sk);
1028 }
1029 
1030 static int sock_reserve_memory(struct sock *sk, int bytes)
1031 {
1032 	long allocated;
1033 	bool charged;
1034 	int pages;
1035 
1036 	if (!mem_cgroup_sk_enabled(sk) || !sk_has_account(sk))
1037 		return -EOPNOTSUPP;
1038 
1039 	if (!bytes)
1040 		return 0;
1041 
1042 	pages = sk_mem_pages(bytes);
1043 
1044 	/* pre-charge to memcg */
1045 	charged = mem_cgroup_sk_charge(sk, pages,
1046 				       GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1047 	if (!charged)
1048 		return -ENOMEM;
1049 
1050 	if (sk->sk_bypass_prot_mem)
1051 		goto success;
1052 
1053 	/* pre-charge to forward_alloc */
1054 	sk_memory_allocated_add(sk, pages);
1055 	allocated = sk_memory_allocated(sk);
1056 
1057 	/* If the system goes into memory pressure with this
1058 	 * precharge, give up and return error.
1059 	 */
1060 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1061 		sk_memory_allocated_sub(sk, pages);
1062 		mem_cgroup_sk_uncharge(sk, pages);
1063 		return -ENOMEM;
1064 	}
1065 
1066 success:
1067 	sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1068 
1069 	WRITE_ONCE(sk->sk_reserved_mem,
1070 		   sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1071 
1072 	return 0;
1073 }
1074 
1075 #ifdef CONFIG_PAGE_POOL
1076 
1077 /* This is the number of tokens and frags that the user can SO_DEVMEM_DONTNEED
1078  * in 1 syscall. The limit exists to limit the amount of memory the kernel
1079  * allocates to copy these tokens, and to prevent looping over the frags for
1080  * too long.
1081  */
1082 #define MAX_DONTNEED_TOKENS 128
1083 #define MAX_DONTNEED_FRAGS 1024
1084 
1085 static noinline_for_stack int
1086 sock_devmem_dontneed(struct sock *sk, sockptr_t optval, unsigned int optlen)
1087 {
1088 	unsigned int num_tokens, i, j, k, netmem_num = 0;
1089 	struct dmabuf_token *tokens;
1090 	int ret = 0, num_frags = 0;
1091 	netmem_ref netmems[16];
1092 
1093 	if (!sk_is_tcp(sk))
1094 		return -EBADF;
1095 
1096 	if (optlen % sizeof(*tokens) ||
1097 	    optlen > sizeof(*tokens) * MAX_DONTNEED_TOKENS)
1098 		return -EINVAL;
1099 
1100 	num_tokens = optlen / sizeof(*tokens);
1101 	tokens = kvmalloc_objs(*tokens, num_tokens);
1102 	if (!tokens)
1103 		return -ENOMEM;
1104 
1105 	if (copy_from_sockptr(tokens, optval, optlen)) {
1106 		kvfree(tokens);
1107 		return -EFAULT;
1108 	}
1109 
1110 	xa_lock_bh(&sk->sk_user_frags);
1111 	for (i = 0; i < num_tokens; i++) {
1112 		for (j = 0; j < tokens[i].token_count; j++) {
1113 			if (++num_frags > MAX_DONTNEED_FRAGS)
1114 				goto frag_limit_reached;
1115 
1116 			netmem_ref netmem = (__force netmem_ref)__xa_erase(
1117 				&sk->sk_user_frags, tokens[i].token_start + j);
1118 
1119 			if (!netmem || WARN_ON_ONCE(!netmem_is_net_iov(netmem)))
1120 				continue;
1121 
1122 			netmems[netmem_num++] = netmem;
1123 			if (netmem_num == ARRAY_SIZE(netmems)) {
1124 				xa_unlock_bh(&sk->sk_user_frags);
1125 				for (k = 0; k < netmem_num; k++)
1126 					WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1127 				netmem_num = 0;
1128 				xa_lock_bh(&sk->sk_user_frags);
1129 			}
1130 			ret++;
1131 		}
1132 	}
1133 
1134 frag_limit_reached:
1135 	xa_unlock_bh(&sk->sk_user_frags);
1136 	for (k = 0; k < netmem_num; k++)
1137 		WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1138 
1139 	kvfree(tokens);
1140 	return ret;
1141 }
1142 #endif
1143 
1144 void sockopt_lock_sock(struct sock *sk)
1145 {
1146 	/* When current->bpf_ctx is set, the setsockopt is called from
1147 	 * a bpf prog.  bpf has ensured the sk lock has been
1148 	 * acquired before calling setsockopt().
1149 	 */
1150 	if (has_current_bpf_ctx())
1151 		return;
1152 
1153 	lock_sock(sk);
1154 }
1155 EXPORT_SYMBOL(sockopt_lock_sock);
1156 
1157 void sockopt_release_sock(struct sock *sk)
1158 {
1159 	if (has_current_bpf_ctx())
1160 		return;
1161 
1162 	release_sock(sk);
1163 }
1164 EXPORT_SYMBOL(sockopt_release_sock);
1165 
1166 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1167 {
1168 	return has_current_bpf_ctx() || ns_capable(ns, cap);
1169 }
1170 EXPORT_SYMBOL(sockopt_ns_capable);
1171 
1172 bool sockopt_capable(int cap)
1173 {
1174 	return has_current_bpf_ctx() || capable(cap);
1175 }
1176 EXPORT_SYMBOL(sockopt_capable);
1177 
1178 static int sockopt_validate_clockid(__kernel_clockid_t value)
1179 {
1180 	switch (value) {
1181 	case CLOCK_REALTIME:
1182 	case CLOCK_MONOTONIC:
1183 	case CLOCK_TAI:
1184 		return 0;
1185 	}
1186 	return -EINVAL;
1187 }
1188 
1189 /*
1190  *	This is meant for all protocols to use and covers goings on
1191  *	at the socket level. Everything here is generic.
1192  */
1193 
1194 int sk_setsockopt(struct sock *sk, int level, int optname,
1195 		  sockptr_t optval, unsigned int optlen)
1196 {
1197 	struct so_timestamping timestamping;
1198 	struct socket *sock = sk->sk_socket;
1199 	struct sock_txtime sk_txtime;
1200 	int val;
1201 	int valbool;
1202 	struct linger ling;
1203 	int ret = 0;
1204 
1205 	/*
1206 	 *	Options without arguments
1207 	 */
1208 
1209 	if (optname == SO_BINDTODEVICE)
1210 		return sock_setbindtodevice(sk, optval, optlen);
1211 
1212 	if (optlen < sizeof(int))
1213 		return -EINVAL;
1214 
1215 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1216 		return -EFAULT;
1217 
1218 	valbool = val ? 1 : 0;
1219 
1220 	/* handle options which do not require locking the socket. */
1221 	switch (optname) {
1222 	case SO_PRIORITY:
1223 		if (sk_set_prio_allowed(sk, val)) {
1224 			sock_set_priority(sk, val);
1225 			return 0;
1226 		}
1227 		return -EPERM;
1228 	case SO_TYPE:
1229 	case SO_PROTOCOL:
1230 	case SO_DOMAIN:
1231 	case SO_ERROR:
1232 		return -ENOPROTOOPT;
1233 #ifdef CONFIG_NET_RX_BUSY_POLL
1234 	case SO_BUSY_POLL:
1235 		if (val < 0)
1236 			return -EINVAL;
1237 		WRITE_ONCE(sk->sk_ll_usec, val);
1238 		return 0;
1239 	case SO_PREFER_BUSY_POLL:
1240 		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1241 			return -EPERM;
1242 		WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1243 		return 0;
1244 	case SO_BUSY_POLL_BUDGET:
1245 		if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1246 		    !sockopt_capable(CAP_NET_ADMIN))
1247 			return -EPERM;
1248 		if (val < 0 || val > U16_MAX)
1249 			return -EINVAL;
1250 		WRITE_ONCE(sk->sk_busy_poll_budget, val);
1251 		return 0;
1252 #endif
1253 	case SO_MAX_PACING_RATE:
1254 		{
1255 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1256 		unsigned long pacing_rate;
1257 
1258 		if (sizeof(ulval) != sizeof(val) &&
1259 		    optlen >= sizeof(ulval) &&
1260 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1261 			return -EFAULT;
1262 		}
1263 		if (ulval != ~0UL)
1264 			cmpxchg(&sk->sk_pacing_status,
1265 				SK_PACING_NONE,
1266 				SK_PACING_NEEDED);
1267 		/* Pairs with READ_ONCE() from sk_getsockopt() */
1268 		WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1269 		pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1270 		if (ulval < pacing_rate)
1271 			WRITE_ONCE(sk->sk_pacing_rate, ulval);
1272 		return 0;
1273 		}
1274 	case SO_TXREHASH:
1275 		if (!sk_is_tcp(sk))
1276 			return -EOPNOTSUPP;
1277 		if (val < -1 || val > 1)
1278 			return -EINVAL;
1279 		if ((u8)val == SOCK_TXREHASH_DEFAULT)
1280 			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1281 		/* Paired with READ_ONCE() in tcp_rtx_synack()
1282 		 * and sk_getsockopt().
1283 		 */
1284 		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1285 		return 0;
1286 	case SO_PEEK_OFF:
1287 		{
1288 		int (*set_peek_off)(struct sock *sk, int val);
1289 
1290 		set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1291 		if (set_peek_off)
1292 			ret = set_peek_off(sk, val);
1293 		else
1294 			ret = -EOPNOTSUPP;
1295 		return ret;
1296 		}
1297 #ifdef CONFIG_PAGE_POOL
1298 	case SO_DEVMEM_DONTNEED:
1299 		return sock_devmem_dontneed(sk, optval, optlen);
1300 #endif
1301 	case SO_SNDTIMEO_OLD:
1302 	case SO_SNDTIMEO_NEW:
1303 		return sock_set_timeout(&sk->sk_sndtimeo, optval,
1304 					optlen, optname == SO_SNDTIMEO_OLD);
1305 	case SO_RCVTIMEO_OLD:
1306 	case SO_RCVTIMEO_NEW:
1307 		return sock_set_timeout(&sk->sk_rcvtimeo, optval,
1308 					optlen, optname == SO_RCVTIMEO_OLD);
1309 	}
1310 
1311 	sockopt_lock_sock(sk);
1312 
1313 	switch (optname) {
1314 	case SO_DEBUG:
1315 		if (val && !sockopt_capable(CAP_NET_ADMIN))
1316 			ret = -EACCES;
1317 		else
1318 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1319 		break;
1320 	case SO_REUSEADDR:
1321 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1322 		break;
1323 	case SO_REUSEPORT:
1324 		if (valbool && !sk_is_inet(sk))
1325 			ret = -EOPNOTSUPP;
1326 		else
1327 			sk->sk_reuseport = valbool;
1328 		break;
1329 	case SO_DONTROUTE:
1330 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1331 		sk_dst_reset(sk);
1332 		break;
1333 	case SO_BROADCAST:
1334 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1335 		break;
1336 	case SO_SNDBUF:
1337 		/* Don't error on this BSD doesn't and if you think
1338 		 * about it this is right. Otherwise apps have to
1339 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1340 		 * are treated in BSD as hints
1341 		 */
1342 		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1343 set_sndbuf:
1344 		/* Ensure val * 2 fits into an int, to prevent max_t()
1345 		 * from treating it as a negative value.
1346 		 */
1347 		val = min_t(int, val, INT_MAX / 2);
1348 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1349 		WRITE_ONCE(sk->sk_sndbuf,
1350 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1351 		/* Wake up sending tasks if we upped the value. */
1352 		sk->sk_write_space(sk);
1353 		break;
1354 
1355 	case SO_SNDBUFFORCE:
1356 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1357 			ret = -EPERM;
1358 			break;
1359 		}
1360 
1361 		/* No negative values (to prevent underflow, as val will be
1362 		 * multiplied by 2).
1363 		 */
1364 		if (val < 0)
1365 			val = 0;
1366 		goto set_sndbuf;
1367 
1368 	case SO_RCVBUF:
1369 		/* Don't error on this BSD doesn't and if you think
1370 		 * about it this is right. Otherwise apps have to
1371 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1372 		 * are treated in BSD as hints
1373 		 */
1374 		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1375 		break;
1376 
1377 	case SO_RCVBUFFORCE:
1378 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1379 			ret = -EPERM;
1380 			break;
1381 		}
1382 
1383 		/* No negative values (to prevent underflow, as val will be
1384 		 * multiplied by 2).
1385 		 */
1386 		__sock_set_rcvbuf(sk, max(val, 0));
1387 		break;
1388 
1389 	case SO_KEEPALIVE:
1390 		if (sk->sk_prot->keepalive)
1391 			sk->sk_prot->keepalive(sk, valbool);
1392 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1393 		break;
1394 
1395 	case SO_OOBINLINE:
1396 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1397 		break;
1398 
1399 	case SO_NO_CHECK:
1400 		sk->sk_no_check_tx = valbool;
1401 		break;
1402 
1403 	case SO_LINGER:
1404 		if (optlen < sizeof(ling)) {
1405 			ret = -EINVAL;	/* 1003.1g */
1406 			break;
1407 		}
1408 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1409 			ret = -EFAULT;
1410 			break;
1411 		}
1412 		if (!ling.l_onoff) {
1413 			sock_reset_flag(sk, SOCK_LINGER);
1414 		} else {
1415 			unsigned long t_sec = ling.l_linger;
1416 
1417 			if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1418 				WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1419 			else
1420 				WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
1421 			sock_set_flag(sk, SOCK_LINGER);
1422 		}
1423 		break;
1424 
1425 	case SO_BSDCOMPAT:
1426 		break;
1427 
1428 	case SO_TIMESTAMP_OLD:
1429 	case SO_TIMESTAMP_NEW:
1430 	case SO_TIMESTAMPNS_OLD:
1431 	case SO_TIMESTAMPNS_NEW:
1432 		sock_set_timestamp(sk, optname, valbool);
1433 		break;
1434 
1435 	case SO_TIMESTAMPING_NEW:
1436 	case SO_TIMESTAMPING_OLD:
1437 		if (optlen == sizeof(timestamping)) {
1438 			if (copy_from_sockptr(&timestamping, optval,
1439 					      sizeof(timestamping))) {
1440 				ret = -EFAULT;
1441 				break;
1442 			}
1443 		} else {
1444 			memset(&timestamping, 0, sizeof(timestamping));
1445 			timestamping.flags = val;
1446 		}
1447 		ret = sock_set_timestamping(sk, optname, timestamping);
1448 		break;
1449 
1450 	case SO_RCVLOWAT:
1451 		{
1452 		int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
1453 
1454 		if (val < 0)
1455 			val = INT_MAX;
1456 		if (sock)
1457 			set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1458 		if (set_rcvlowat)
1459 			ret = set_rcvlowat(sk, val);
1460 		else
1461 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1462 		break;
1463 		}
1464 	case SO_ATTACH_FILTER: {
1465 		struct sock_fprog fprog;
1466 
1467 		if (sk_is_tcp(sk) &&
1468 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1469 			ret = -EPERM;
1470 			break;
1471 		}
1472 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1473 		if (!ret)
1474 			ret = sk_attach_filter(&fprog, sk);
1475 		break;
1476 	}
1477 	case SO_ATTACH_BPF:
1478 		ret = -EINVAL;
1479 		if (optlen == sizeof(u32)) {
1480 			u32 ufd;
1481 
1482 			ret = -EFAULT;
1483 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1484 				break;
1485 
1486 			ret = sk_attach_bpf(ufd, sk);
1487 		}
1488 		break;
1489 
1490 	case SO_ATTACH_REUSEPORT_CBPF: {
1491 		struct sock_fprog fprog;
1492 
1493 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1494 		if (!ret)
1495 			ret = sk_reuseport_attach_filter(&fprog, sk);
1496 		break;
1497 	}
1498 	case SO_ATTACH_REUSEPORT_EBPF:
1499 		ret = -EINVAL;
1500 		if (optlen == sizeof(u32)) {
1501 			u32 ufd;
1502 
1503 			ret = -EFAULT;
1504 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1505 				break;
1506 
1507 			ret = sk_reuseport_attach_bpf(ufd, sk);
1508 		}
1509 		break;
1510 
1511 	case SO_DETACH_REUSEPORT_BPF:
1512 		ret = reuseport_detach_prog(sk);
1513 		break;
1514 
1515 	case SO_DETACH_FILTER:
1516 		ret = sk_detach_filter(sk);
1517 		break;
1518 
1519 	case SO_LOCK_FILTER:
1520 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1521 			ret = -EPERM;
1522 		else
1523 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1524 		break;
1525 
1526 	case SO_MARK:
1527 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1528 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1529 			ret = -EPERM;
1530 			break;
1531 		}
1532 
1533 		__sock_set_mark(sk, val);
1534 		break;
1535 	case SO_RCVMARK:
1536 		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1537 		break;
1538 
1539 	case SO_RCVPRIORITY:
1540 		sock_valbool_flag(sk, SOCK_RCVPRIORITY, valbool);
1541 		break;
1542 
1543 	case SO_RXQ_OVFL:
1544 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1545 		break;
1546 
1547 	case SO_WIFI_STATUS:
1548 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1549 		break;
1550 
1551 	case SO_NOFCS:
1552 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1553 		break;
1554 
1555 	case SO_SELECT_ERR_QUEUE:
1556 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1557 		break;
1558 
1559 	case SO_PASSCRED:
1560 		if (sk_may_scm_recv(sk))
1561 			sk->sk_scm_credentials = valbool;
1562 		else
1563 			ret = -EOPNOTSUPP;
1564 		break;
1565 
1566 	case SO_PASSSEC:
1567 		if (IS_ENABLED(CONFIG_SECURITY_NETWORK) && sk_may_scm_recv(sk))
1568 			sk->sk_scm_security = valbool;
1569 		else
1570 			ret = -EOPNOTSUPP;
1571 		break;
1572 
1573 	case SO_PASSPIDFD:
1574 		if (sk_is_unix(sk))
1575 			sk->sk_scm_pidfd = valbool;
1576 		else
1577 			ret = -EOPNOTSUPP;
1578 		break;
1579 
1580 	case SO_PASSRIGHTS:
1581 		if (sk_is_unix(sk))
1582 			sk->sk_scm_rights = valbool;
1583 		else
1584 			ret = -EOPNOTSUPP;
1585 		break;
1586 
1587 	case SO_INCOMING_CPU:
1588 		reuseport_update_incoming_cpu(sk, val);
1589 		break;
1590 
1591 	case SO_CNX_ADVICE:
1592 		if (val == 1)
1593 			dst_negative_advice(sk);
1594 		break;
1595 
1596 	case SO_ZEROCOPY:
1597 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1598 			if (!(sk_is_tcp(sk) ||
1599 			      (sk->sk_type == SOCK_DGRAM &&
1600 			       sk->sk_protocol == IPPROTO_UDP)))
1601 				ret = -EOPNOTSUPP;
1602 		} else if (sk->sk_family != PF_RDS) {
1603 			ret = -EOPNOTSUPP;
1604 		}
1605 		if (!ret) {
1606 			if (val < 0 || val > 1)
1607 				ret = -EINVAL;
1608 			else
1609 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1610 		}
1611 		break;
1612 
1613 	case SO_TXTIME:
1614 		if (optlen != sizeof(struct sock_txtime)) {
1615 			ret = -EINVAL;
1616 			break;
1617 		} else if (copy_from_sockptr(&sk_txtime, optval,
1618 			   sizeof(struct sock_txtime))) {
1619 			ret = -EFAULT;
1620 			break;
1621 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1622 			ret = -EINVAL;
1623 			break;
1624 		}
1625 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1626 		 * scheduler has enough safe guards.
1627 		 */
1628 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1629 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1630 			ret = -EPERM;
1631 			break;
1632 		}
1633 
1634 		ret = sockopt_validate_clockid(sk_txtime.clockid);
1635 		if (ret)
1636 			break;
1637 
1638 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1639 		sk->sk_clockid = sk_txtime.clockid;
1640 		sk->sk_txtime_deadline_mode =
1641 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1642 		sk->sk_txtime_report_errors =
1643 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1644 		break;
1645 
1646 	case SO_BINDTOIFINDEX:
1647 		ret = sock_bindtoindex_locked(sk, val);
1648 		break;
1649 
1650 	case SO_BUF_LOCK:
1651 		if (val & ~SOCK_BUF_LOCK_MASK) {
1652 			ret = -EINVAL;
1653 			break;
1654 		}
1655 		sk->sk_userlocks = val | (sk->sk_userlocks &
1656 					  ~SOCK_BUF_LOCK_MASK);
1657 		break;
1658 
1659 	case SO_RESERVE_MEM:
1660 	{
1661 		int delta;
1662 
1663 		if (val < 0) {
1664 			ret = -EINVAL;
1665 			break;
1666 		}
1667 
1668 		delta = val - sk->sk_reserved_mem;
1669 		if (delta < 0)
1670 			sock_release_reserved_memory(sk, -delta);
1671 		else
1672 			ret = sock_reserve_memory(sk, delta);
1673 		break;
1674 	}
1675 
1676 	default:
1677 		ret = -ENOPROTOOPT;
1678 		break;
1679 	}
1680 	sockopt_release_sock(sk);
1681 	return ret;
1682 }
1683 
1684 int sock_setsockopt(struct socket *sock, int level, int optname,
1685 		    sockptr_t optval, unsigned int optlen)
1686 {
1687 	return sk_setsockopt(sock->sk, level, optname,
1688 			     optval, optlen);
1689 }
1690 EXPORT_SYMBOL(sock_setsockopt);
1691 
1692 static const struct cred *sk_get_peer_cred(struct sock *sk)
1693 {
1694 	const struct cred *cred;
1695 
1696 	spin_lock(&sk->sk_peer_lock);
1697 	cred = get_cred(sk->sk_peer_cred);
1698 	spin_unlock(&sk->sk_peer_lock);
1699 
1700 	return cred;
1701 }
1702 
1703 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1704 			  struct ucred *ucred)
1705 {
1706 	ucred->pid = pid_vnr(pid);
1707 	ucred->uid = ucred->gid = -1;
1708 	if (cred) {
1709 		struct user_namespace *current_ns = current_user_ns();
1710 
1711 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1712 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1713 	}
1714 }
1715 
1716 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1717 {
1718 	struct user_namespace *user_ns = current_user_ns();
1719 	int i;
1720 
1721 	for (i = 0; i < src->ngroups; i++) {
1722 		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1723 
1724 		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1725 			return -EFAULT;
1726 	}
1727 
1728 	return 0;
1729 }
1730 
1731 int sk_getsockopt(struct sock *sk, int level, int optname,
1732 		  sockptr_t optval, sockptr_t optlen)
1733 {
1734 	struct socket *sock = sk->sk_socket;
1735 
1736 	union {
1737 		int val;
1738 		u64 val64;
1739 		unsigned long ulval;
1740 		struct linger ling;
1741 		struct old_timeval32 tm32;
1742 		struct __kernel_old_timeval tm;
1743 		struct  __kernel_sock_timeval stm;
1744 		struct sock_txtime txtime;
1745 		struct so_timestamping timestamping;
1746 	} v;
1747 
1748 	int lv = sizeof(int);
1749 	int len;
1750 
1751 	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1752 		return -EFAULT;
1753 	if (len < 0)
1754 		return -EINVAL;
1755 
1756 	memset(&v, 0, sizeof(v));
1757 
1758 	switch (optname) {
1759 	case SO_DEBUG:
1760 		v.val = sock_flag(sk, SOCK_DBG);
1761 		break;
1762 
1763 	case SO_DONTROUTE:
1764 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1765 		break;
1766 
1767 	case SO_BROADCAST:
1768 		v.val = sock_flag(sk, SOCK_BROADCAST);
1769 		break;
1770 
1771 	case SO_SNDBUF:
1772 		v.val = READ_ONCE(sk->sk_sndbuf);
1773 		break;
1774 
1775 	case SO_RCVBUF:
1776 		v.val = READ_ONCE(sk->sk_rcvbuf);
1777 		break;
1778 
1779 	case SO_REUSEADDR:
1780 		v.val = sk->sk_reuse;
1781 		break;
1782 
1783 	case SO_REUSEPORT:
1784 		v.val = sk->sk_reuseport;
1785 		break;
1786 
1787 	case SO_KEEPALIVE:
1788 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1789 		break;
1790 
1791 	case SO_TYPE:
1792 		v.val = sk->sk_type;
1793 		break;
1794 
1795 	case SO_PROTOCOL:
1796 		v.val = sk->sk_protocol;
1797 		break;
1798 
1799 	case SO_DOMAIN:
1800 		v.val = sk->sk_family;
1801 		break;
1802 
1803 	case SO_ERROR:
1804 		v.val = -sock_error(sk);
1805 		if (v.val == 0)
1806 			v.val = xchg(&sk->sk_err_soft, 0);
1807 		break;
1808 
1809 	case SO_OOBINLINE:
1810 		v.val = sock_flag(sk, SOCK_URGINLINE);
1811 		break;
1812 
1813 	case SO_NO_CHECK:
1814 		v.val = sk->sk_no_check_tx;
1815 		break;
1816 
1817 	case SO_PRIORITY:
1818 		v.val = READ_ONCE(sk->sk_priority);
1819 		break;
1820 
1821 	case SO_LINGER:
1822 		lv		= sizeof(v.ling);
1823 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1824 		v.ling.l_linger	= READ_ONCE(sk->sk_lingertime) / HZ;
1825 		break;
1826 
1827 	case SO_BSDCOMPAT:
1828 		break;
1829 
1830 	case SO_TIMESTAMP_OLD:
1831 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1832 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1833 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1834 		break;
1835 
1836 	case SO_TIMESTAMPNS_OLD:
1837 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1838 		break;
1839 
1840 	case SO_TIMESTAMP_NEW:
1841 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1842 		break;
1843 
1844 	case SO_TIMESTAMPNS_NEW:
1845 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1846 		break;
1847 
1848 	case SO_TIMESTAMPING_OLD:
1849 	case SO_TIMESTAMPING_NEW:
1850 		lv = sizeof(v.timestamping);
1851 		/* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1852 		 * returning the flags when they were set through the same option.
1853 		 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1854 		 */
1855 		if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1856 			v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1857 			v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1858 		}
1859 		break;
1860 
1861 	case SO_RCVTIMEO_OLD:
1862 	case SO_RCVTIMEO_NEW:
1863 		lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1864 				      SO_RCVTIMEO_OLD == optname);
1865 		break;
1866 
1867 	case SO_SNDTIMEO_OLD:
1868 	case SO_SNDTIMEO_NEW:
1869 		lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1870 				      SO_SNDTIMEO_OLD == optname);
1871 		break;
1872 
1873 	case SO_RCVLOWAT:
1874 		v.val = READ_ONCE(sk->sk_rcvlowat);
1875 		break;
1876 
1877 	case SO_SNDLOWAT:
1878 		v.val = 1;
1879 		break;
1880 
1881 	case SO_PASSCRED:
1882 		if (!sk_may_scm_recv(sk))
1883 			return -EOPNOTSUPP;
1884 
1885 		v.val = sk->sk_scm_credentials;
1886 		break;
1887 
1888 	case SO_PASSPIDFD:
1889 		if (!sk_is_unix(sk))
1890 			return -EOPNOTSUPP;
1891 
1892 		v.val = sk->sk_scm_pidfd;
1893 		break;
1894 
1895 	case SO_PASSRIGHTS:
1896 		if (!sk_is_unix(sk))
1897 			return -EOPNOTSUPP;
1898 
1899 		v.val = sk->sk_scm_rights;
1900 		break;
1901 
1902 	case SO_PEERCRED:
1903 	{
1904 		struct ucred peercred;
1905 		if (len > sizeof(peercred))
1906 			len = sizeof(peercred);
1907 
1908 		spin_lock(&sk->sk_peer_lock);
1909 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1910 		spin_unlock(&sk->sk_peer_lock);
1911 
1912 		if (copy_to_sockptr(optval, &peercred, len))
1913 			return -EFAULT;
1914 		goto lenout;
1915 	}
1916 
1917 	case SO_PEERPIDFD:
1918 	{
1919 		struct pid *peer_pid;
1920 		struct file *pidfd_file = NULL;
1921 		unsigned int flags = 0;
1922 		int pidfd;
1923 
1924 		if (len > sizeof(pidfd))
1925 			len = sizeof(pidfd);
1926 
1927 		spin_lock(&sk->sk_peer_lock);
1928 		peer_pid = get_pid(sk->sk_peer_pid);
1929 		spin_unlock(&sk->sk_peer_lock);
1930 
1931 		if (!peer_pid)
1932 			return -ENODATA;
1933 
1934 		/* The use of PIDFD_STALE requires stashing of struct pid
1935 		 * on pidfs with pidfs_register_pid() and only AF_UNIX
1936 		 * were prepared for this.
1937 		 */
1938 		if (sk->sk_family == AF_UNIX)
1939 			flags = PIDFD_STALE;
1940 
1941 		pidfd = pidfd_prepare(peer_pid, flags, &pidfd_file);
1942 		put_pid(peer_pid);
1943 		if (pidfd < 0)
1944 			return pidfd;
1945 
1946 		if (copy_to_sockptr(optval, &pidfd, len) ||
1947 		    copy_to_sockptr(optlen, &len, sizeof(int))) {
1948 			put_unused_fd(pidfd);
1949 			fput(pidfd_file);
1950 
1951 			return -EFAULT;
1952 		}
1953 
1954 		fd_install(pidfd, pidfd_file);
1955 		return 0;
1956 	}
1957 
1958 	case SO_PEERGROUPS:
1959 	{
1960 		const struct cred *cred;
1961 		int ret, n;
1962 
1963 		cred = sk_get_peer_cred(sk);
1964 		if (!cred)
1965 			return -ENODATA;
1966 
1967 		n = cred->group_info->ngroups;
1968 		if (len < n * sizeof(gid_t)) {
1969 			len = n * sizeof(gid_t);
1970 			put_cred(cred);
1971 			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1972 		}
1973 		len = n * sizeof(gid_t);
1974 
1975 		ret = groups_to_user(optval, cred->group_info);
1976 		put_cred(cred);
1977 		if (ret)
1978 			return ret;
1979 		goto lenout;
1980 	}
1981 
1982 	case SO_PEERNAME:
1983 	{
1984 		struct sockaddr_storage address;
1985 
1986 		lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1987 		if (lv < 0)
1988 			return -ENOTCONN;
1989 		if (lv < len)
1990 			return -EINVAL;
1991 		if (copy_to_sockptr(optval, &address, len))
1992 			return -EFAULT;
1993 		goto lenout;
1994 	}
1995 
1996 	/* Dubious BSD thing... Probably nobody even uses it, but
1997 	 * the UNIX standard wants it for whatever reason... -DaveM
1998 	 */
1999 	case SO_ACCEPTCONN:
2000 		v.val = sk->sk_state == TCP_LISTEN;
2001 		break;
2002 
2003 	case SO_PASSSEC:
2004 		if (!IS_ENABLED(CONFIG_SECURITY_NETWORK) || !sk_may_scm_recv(sk))
2005 			return -EOPNOTSUPP;
2006 
2007 		v.val = sk->sk_scm_security;
2008 		break;
2009 
2010 	case SO_PEERSEC:
2011 		return security_socket_getpeersec_stream(sock,
2012 							 optval, optlen, len);
2013 
2014 	case SO_MARK:
2015 		v.val = READ_ONCE(sk->sk_mark);
2016 		break;
2017 
2018 	case SO_RCVMARK:
2019 		v.val = sock_flag(sk, SOCK_RCVMARK);
2020 		break;
2021 
2022 	case SO_RCVPRIORITY:
2023 		v.val = sock_flag(sk, SOCK_RCVPRIORITY);
2024 		break;
2025 
2026 	case SO_RXQ_OVFL:
2027 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
2028 		break;
2029 
2030 	case SO_WIFI_STATUS:
2031 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
2032 		break;
2033 
2034 	case SO_PEEK_OFF:
2035 		if (!READ_ONCE(sock->ops)->set_peek_off)
2036 			return -EOPNOTSUPP;
2037 
2038 		v.val = READ_ONCE(sk->sk_peek_off);
2039 		break;
2040 	case SO_NOFCS:
2041 		v.val = sock_flag(sk, SOCK_NOFCS);
2042 		break;
2043 
2044 	case SO_BINDTODEVICE:
2045 		return sock_getbindtodevice(sk, optval, optlen, len);
2046 
2047 	case SO_GET_FILTER:
2048 		len = sk_get_filter(sk, optval, len);
2049 		if (len < 0)
2050 			return len;
2051 
2052 		goto lenout;
2053 
2054 	case SO_LOCK_FILTER:
2055 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
2056 		break;
2057 
2058 	case SO_BPF_EXTENSIONS:
2059 		v.val = bpf_tell_extensions();
2060 		break;
2061 
2062 	case SO_SELECT_ERR_QUEUE:
2063 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
2064 		break;
2065 
2066 #ifdef CONFIG_NET_RX_BUSY_POLL
2067 	case SO_BUSY_POLL:
2068 		v.val = READ_ONCE(sk->sk_ll_usec);
2069 		break;
2070 	case SO_PREFER_BUSY_POLL:
2071 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
2072 		break;
2073 #endif
2074 
2075 	case SO_MAX_PACING_RATE:
2076 		/* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
2077 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
2078 			lv = sizeof(v.ulval);
2079 			v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
2080 		} else {
2081 			/* 32bit version */
2082 			v.val = min_t(unsigned long, ~0U,
2083 				      READ_ONCE(sk->sk_max_pacing_rate));
2084 		}
2085 		break;
2086 
2087 	case SO_INCOMING_CPU:
2088 		v.val = READ_ONCE(sk->sk_incoming_cpu);
2089 		break;
2090 
2091 	case SO_MEMINFO:
2092 	{
2093 		u32 meminfo[SK_MEMINFO_VARS];
2094 
2095 		sk_get_meminfo(sk, meminfo);
2096 
2097 		len = min_t(unsigned int, len, sizeof(meminfo));
2098 		if (copy_to_sockptr(optval, &meminfo, len))
2099 			return -EFAULT;
2100 
2101 		goto lenout;
2102 	}
2103 
2104 #ifdef CONFIG_NET_RX_BUSY_POLL
2105 	case SO_INCOMING_NAPI_ID:
2106 		v.val = READ_ONCE(sk->sk_napi_id);
2107 
2108 		/* aggregate non-NAPI IDs down to 0 */
2109 		if (!napi_id_valid(v.val))
2110 			v.val = 0;
2111 
2112 		break;
2113 #endif
2114 
2115 	case SO_COOKIE:
2116 		lv = sizeof(u64);
2117 		if (len < lv)
2118 			return -EINVAL;
2119 		v.val64 = sock_gen_cookie(sk);
2120 		break;
2121 
2122 	case SO_ZEROCOPY:
2123 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
2124 		break;
2125 
2126 	case SO_TXTIME:
2127 		lv = sizeof(v.txtime);
2128 		v.txtime.clockid = sk->sk_clockid;
2129 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
2130 				  SOF_TXTIME_DEADLINE_MODE : 0;
2131 		v.txtime.flags |= sk->sk_txtime_report_errors ?
2132 				  SOF_TXTIME_REPORT_ERRORS : 0;
2133 		break;
2134 
2135 	case SO_BINDTOIFINDEX:
2136 		v.val = READ_ONCE(sk->sk_bound_dev_if);
2137 		break;
2138 
2139 	case SO_NETNS_COOKIE:
2140 		lv = sizeof(u64);
2141 		if (len != lv)
2142 			return -EINVAL;
2143 		v.val64 = sock_net(sk)->net_cookie;
2144 		break;
2145 
2146 	case SO_BUF_LOCK:
2147 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
2148 		break;
2149 
2150 	case SO_RESERVE_MEM:
2151 		v.val = READ_ONCE(sk->sk_reserved_mem);
2152 		break;
2153 
2154 	case SO_TXREHASH:
2155 		if (!sk_is_tcp(sk))
2156 			return -EOPNOTSUPP;
2157 
2158 		/* Paired with WRITE_ONCE() in sk_setsockopt() */
2159 		v.val = READ_ONCE(sk->sk_txrehash);
2160 		break;
2161 
2162 	default:
2163 		/* We implement the SO_SNDLOWAT etc to not be settable
2164 		 * (1003.1g 7).
2165 		 */
2166 		return -ENOPROTOOPT;
2167 	}
2168 
2169 	if (len > lv)
2170 		len = lv;
2171 	if (copy_to_sockptr(optval, &v, len))
2172 		return -EFAULT;
2173 lenout:
2174 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
2175 		return -EFAULT;
2176 	return 0;
2177 }
2178 
2179 /*
2180  * Initialize an sk_lock.
2181  *
2182  * (We also register the sk_lock with the lock validator.)
2183  */
2184 static inline void sock_lock_init(struct sock *sk)
2185 {
2186 	sk_owner_clear(sk);
2187 
2188 	if (sk->sk_kern_sock)
2189 		sock_lock_init_class_and_name(
2190 			sk,
2191 			af_family_kern_slock_key_strings[sk->sk_family],
2192 			af_family_kern_slock_keys + sk->sk_family,
2193 			af_family_kern_key_strings[sk->sk_family],
2194 			af_family_kern_keys + sk->sk_family);
2195 	else
2196 		sock_lock_init_class_and_name(
2197 			sk,
2198 			af_family_slock_key_strings[sk->sk_family],
2199 			af_family_slock_keys + sk->sk_family,
2200 			af_family_key_strings[sk->sk_family],
2201 			af_family_keys + sk->sk_family);
2202 }
2203 
2204 /*
2205  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2206  * even temporarily, because of RCU lookups. sk_node should also be left as is.
2207  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2208  */
2209 static void sock_copy(struct sock *nsk, const struct sock *osk)
2210 {
2211 	const struct proto *prot = READ_ONCE(osk->sk_prot);
2212 #ifdef CONFIG_SECURITY_NETWORK
2213 	void *sptr = nsk->sk_security;
2214 #endif
2215 
2216 	/* If we move sk_tx_queue_mapping out of the private section,
2217 	 * we must check if sk_tx_queue_clear() is called after
2218 	 * sock_copy() in sk_clone_lock().
2219 	 */
2220 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2221 		     offsetof(struct sock, sk_dontcopy_begin) ||
2222 		     offsetof(struct sock, sk_tx_queue_mapping) >=
2223 		     offsetof(struct sock, sk_dontcopy_end));
2224 
2225 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2226 
2227 	unsafe_memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2228 		      prot->obj_size - offsetof(struct sock, sk_dontcopy_end),
2229 		      /* alloc is larger than struct, see sk_prot_alloc() */);
2230 
2231 #ifdef CONFIG_SECURITY_NETWORK
2232 	nsk->sk_security = sptr;
2233 	security_sk_clone(osk, nsk);
2234 #endif
2235 }
2236 
2237 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2238 		int family)
2239 {
2240 	struct sock *sk;
2241 	struct kmem_cache *slab;
2242 
2243 	slab = prot->slab;
2244 	if (slab != NULL) {
2245 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2246 		if (!sk)
2247 			return sk;
2248 		if (want_init_on_alloc(priority))
2249 			sk_prot_clear_nulls(sk, prot->obj_size);
2250 	} else
2251 		sk = kmalloc(prot->obj_size, priority);
2252 
2253 	if (sk != NULL) {
2254 		if (security_sk_alloc(sk, family, priority))
2255 			goto out_free;
2256 
2257 		if (!try_module_get(prot->owner))
2258 			goto out_free_sec;
2259 	}
2260 
2261 	return sk;
2262 
2263 out_free_sec:
2264 	security_sk_free(sk);
2265 out_free:
2266 	if (slab != NULL)
2267 		kmem_cache_free(slab, sk);
2268 	else
2269 		kfree(sk);
2270 	return NULL;
2271 }
2272 
2273 static void sk_prot_free(struct proto *prot, struct sock *sk)
2274 {
2275 	struct kmem_cache *slab;
2276 	struct module *owner;
2277 
2278 	owner = prot->owner;
2279 	slab = prot->slab;
2280 
2281 	cgroup_sk_free(&sk->sk_cgrp_data);
2282 	mem_cgroup_sk_free(sk);
2283 	security_sk_free(sk);
2284 
2285 	sk_owner_put(sk);
2286 
2287 	if (slab != NULL)
2288 		kmem_cache_free(slab, sk);
2289 	else
2290 		kfree(sk);
2291 	module_put(owner);
2292 }
2293 
2294 /**
2295  *	sk_alloc - All socket objects are allocated here
2296  *	@net: the applicable net namespace
2297  *	@family: protocol family
2298  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2299  *	@prot: struct proto associated with this new sock instance
2300  *	@kern: is this to be a kernel socket?
2301  */
2302 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2303 		      struct proto *prot, int kern)
2304 {
2305 	struct sock *sk;
2306 
2307 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2308 	if (sk) {
2309 		sk->sk_family = family;
2310 		/*
2311 		 * See comment in struct sock definition to understand
2312 		 * why we need sk_prot_creator -acme
2313 		 */
2314 		sk->sk_prot = sk->sk_prot_creator = prot;
2315 
2316 		if (READ_ONCE(net->core.sysctl_bypass_prot_mem))
2317 			sk->sk_bypass_prot_mem = 1;
2318 
2319 		sk->sk_kern_sock = kern;
2320 		sock_lock_init(sk);
2321 
2322 		sk->sk_net_refcnt = kern ? 0 : 1;
2323 		if (likely(sk->sk_net_refcnt)) {
2324 			get_net_track(net, &sk->ns_tracker, priority);
2325 			sock_inuse_add(net, 1);
2326 		} else {
2327 			net_passive_inc(net);
2328 			__netns_tracker_alloc(net, &sk->ns_tracker,
2329 					      false, priority);
2330 		}
2331 
2332 		sock_net_set(sk, net);
2333 		refcount_set(&sk->sk_wmem_alloc, SK_WMEM_ALLOC_BIAS);
2334 
2335 		mem_cgroup_sk_alloc(sk);
2336 		cgroup_sk_alloc(&sk->sk_cgrp_data);
2337 		sock_update_classid(&sk->sk_cgrp_data);
2338 		sock_update_netprioidx(&sk->sk_cgrp_data);
2339 		sk_tx_queue_clear(sk);
2340 	}
2341 
2342 	return sk;
2343 }
2344 EXPORT_SYMBOL(sk_alloc);
2345 
2346 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2347  * grace period. This is the case for UDP sockets and TCP listeners.
2348  */
2349 static void __sk_destruct(struct rcu_head *head)
2350 {
2351 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2352 	struct net *net = sock_net(sk);
2353 	struct sk_filter *filter;
2354 
2355 	if (sk->sk_destruct)
2356 		sk->sk_destruct(sk);
2357 
2358 	filter = rcu_dereference_check(sk->sk_filter,
2359 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2360 	if (filter) {
2361 		sk_filter_uncharge(sk, filter);
2362 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2363 	}
2364 
2365 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2366 
2367 #ifdef CONFIG_BPF_SYSCALL
2368 	bpf_sk_storage_free(sk);
2369 #endif
2370 
2371 	if (atomic_read(&sk->sk_omem_alloc))
2372 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2373 			 __func__, atomic_read(&sk->sk_omem_alloc));
2374 
2375 	if (sk->sk_frag.page) {
2376 		put_page(sk->sk_frag.page);
2377 		sk->sk_frag.page = NULL;
2378 	}
2379 
2380 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2381 	put_cred(sk->sk_peer_cred);
2382 	put_pid(sk->sk_peer_pid);
2383 
2384 	if (likely(sk->sk_net_refcnt)) {
2385 		put_net_track(net, &sk->ns_tracker);
2386 	} else {
2387 		__netns_tracker_free(net, &sk->ns_tracker, false);
2388 		net_passive_dec(net);
2389 	}
2390 	sk_prot_free(sk->sk_prot_creator, sk);
2391 }
2392 
2393 void sk_net_refcnt_upgrade(struct sock *sk)
2394 {
2395 	struct net *net = sock_net(sk);
2396 
2397 	WARN_ON_ONCE(sk->sk_net_refcnt);
2398 	__netns_tracker_free(net, &sk->ns_tracker, false);
2399 	net_passive_dec(net);
2400 	sk->sk_net_refcnt = 1;
2401 	get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
2402 	sock_inuse_add(net, 1);
2403 }
2404 EXPORT_SYMBOL_GPL(sk_net_refcnt_upgrade);
2405 
2406 void sk_destruct(struct sock *sk)
2407 {
2408 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2409 
2410 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2411 		reuseport_detach_sock(sk);
2412 		use_call_rcu = true;
2413 	}
2414 
2415 	if (use_call_rcu)
2416 		call_rcu(&sk->sk_rcu, __sk_destruct);
2417 	else
2418 		__sk_destruct(&sk->sk_rcu);
2419 }
2420 
2421 static void __sk_free(struct sock *sk)
2422 {
2423 	if (likely(sk->sk_net_refcnt))
2424 		sock_inuse_add(sock_net(sk), -1);
2425 
2426 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2427 		sock_diag_broadcast_destroy(sk);
2428 	else
2429 		sk_destruct(sk);
2430 }
2431 
2432 void sk_free(struct sock *sk)
2433 {
2434 	/*
2435 	 * We subtract one from sk_wmem_alloc and can know if
2436 	 * some packets are still in some tx queue.
2437 	 * If not null, sock_wfree() will call __sk_free(sk) later
2438 	 */
2439 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2440 		__sk_free(sk);
2441 }
2442 EXPORT_SYMBOL(sk_free);
2443 
2444 static void sk_init_common(struct sock *sk)
2445 {
2446 	skb_queue_head_init(&sk->sk_receive_queue);
2447 	skb_queue_head_init(&sk->sk_write_queue);
2448 	skb_queue_head_init(&sk->sk_error_queue);
2449 
2450 	rwlock_init(&sk->sk_callback_lock);
2451 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2452 			af_rlock_keys + sk->sk_family,
2453 			af_family_rlock_key_strings[sk->sk_family]);
2454 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2455 			af_wlock_keys + sk->sk_family,
2456 			af_family_wlock_key_strings[sk->sk_family]);
2457 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2458 			af_elock_keys + sk->sk_family,
2459 			af_family_elock_key_strings[sk->sk_family]);
2460 	if (sk->sk_kern_sock)
2461 		lockdep_set_class_and_name(&sk->sk_callback_lock,
2462 			af_kern_callback_keys + sk->sk_family,
2463 			af_family_kern_clock_key_strings[sk->sk_family]);
2464 	else
2465 		lockdep_set_class_and_name(&sk->sk_callback_lock,
2466 			af_callback_keys + sk->sk_family,
2467 			af_family_clock_key_strings[sk->sk_family]);
2468 }
2469 
2470 /**
2471  * sk_clone - clone a socket
2472  * @sk: the socket to clone
2473  * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2474  * @lock: if true, lock the cloned sk
2475  *
2476  * If @lock is true, the clone is locked by bh_lock_sock(), and
2477  * caller must unlock socket even in error path by bh_unlock_sock().
2478  */
2479 struct sock *sk_clone(const struct sock *sk, const gfp_t priority,
2480 		      bool lock)
2481 {
2482 	struct proto *prot = READ_ONCE(sk->sk_prot);
2483 	struct sk_filter *filter;
2484 	bool is_charged = true;
2485 	struct sock *newsk;
2486 
2487 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2488 	if (!newsk)
2489 		goto out;
2490 
2491 	sock_copy(newsk, sk);
2492 
2493 	newsk->sk_prot_creator = prot;
2494 #ifdef CONFIG_BPF_SYSCALL
2495 	RCU_INIT_POINTER(newsk->sk_bpf_storage, NULL);
2496 #endif
2497 
2498 	/* SANITY */
2499 	if (likely(newsk->sk_net_refcnt)) {
2500 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2501 		sock_inuse_add(sock_net(newsk), 1);
2502 	} else {
2503 		/* Kernel sockets are not elevating the struct net refcount.
2504 		 * Instead, use a tracker to more easily detect if a layer
2505 		 * is not properly dismantling its kernel sockets at netns
2506 		 * destroy time.
2507 		 */
2508 		net_passive_inc(sock_net(newsk));
2509 		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2510 				      false, priority);
2511 	}
2512 
2513 	sk_node_init(&newsk->sk_node);
2514 	sock_lock_init(newsk);
2515 
2516 	if (lock)
2517 		bh_lock_sock(newsk);
2518 
2519 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2520 	newsk->sk_backlog.len = 0;
2521 
2522 	atomic_set(&newsk->sk_rmem_alloc, 0);
2523 
2524 	refcount_set(&newsk->sk_wmem_alloc, SK_WMEM_ALLOC_BIAS);
2525 
2526 	atomic_set(&newsk->sk_omem_alloc, 0);
2527 	sk_init_common(newsk);
2528 
2529 	newsk->sk_dst_cache	= NULL;
2530 	newsk->sk_dst_pending_confirm = 0;
2531 	newsk->sk_wmem_queued	= 0;
2532 	newsk->sk_forward_alloc = 0;
2533 	newsk->sk_reserved_mem  = 0;
2534 	DEBUG_NET_WARN_ON_ONCE(newsk->sk_drop_counters);
2535 	sk_drops_reset(newsk);
2536 	newsk->sk_send_head	= NULL;
2537 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2538 	atomic_set(&newsk->sk_zckey, 0);
2539 
2540 	sock_reset_flag(newsk, SOCK_DONE);
2541 
2542 #ifdef CONFIG_MEMCG
2543 	/* sk->sk_memcg will be populated at accept() time */
2544 	newsk->sk_memcg = NULL;
2545 #endif
2546 
2547 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2548 
2549 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2550 
2551 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2552 		net_enable_timestamp();
2553 
2554 	rcu_read_lock();
2555 	filter = rcu_dereference(sk->sk_filter);
2556 	if (filter != NULL)
2557 		/* though it's an empty new sock, the charging may fail
2558 		 * if sysctl_optmem_max was changed between creation of
2559 		 * original socket and cloning
2560 		 */
2561 		is_charged = sk_filter_charge(newsk, filter);
2562 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2563 	rcu_read_unlock();
2564 
2565 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2566 		/* We need to make sure that we don't uncharge the new
2567 		 * socket if we couldn't charge it in the first place
2568 		 * as otherwise we uncharge the parent's filter.
2569 		 */
2570 		if (!is_charged)
2571 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2572 
2573 		goto free;
2574 	}
2575 
2576 	if (bpf_sk_storage_clone(sk, newsk))
2577 		goto free;
2578 
2579 	/* Clear sk_user_data if parent had the pointer tagged
2580 	 * as not suitable for copying when cloning.
2581 	 */
2582 	if (sk_user_data_is_nocopy(newsk))
2583 		newsk->sk_user_data = NULL;
2584 
2585 	newsk->sk_err	   = 0;
2586 	newsk->sk_err_soft = 0;
2587 	newsk->sk_priority = 0;
2588 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2589 
2590 	/* Before updating sk_refcnt, we must commit prior changes to memory
2591 	 * (Documentation/RCU/rculist_nulls.rst for details)
2592 	 */
2593 	smp_wmb();
2594 	refcount_set(&newsk->sk_refcnt, 2);
2595 
2596 	sk_set_socket(newsk, NULL);
2597 	sk_tx_queue_clear(newsk);
2598 	sk_rx_queue_clear(newsk);
2599 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2600 
2601 	if (newsk->sk_prot->sockets_allocated)
2602 		sk_sockets_allocated_inc(newsk);
2603 out:
2604 	return newsk;
2605 free:
2606 	/* It is still raw copy of parent, so invalidate
2607 	 * destructor and make plain sk_free()
2608 	 */
2609 	newsk->sk_destruct = NULL;
2610 	if (lock)
2611 		bh_unlock_sock(newsk);
2612 	sk_free(newsk);
2613 	newsk = NULL;
2614 	goto out;
2615 }
2616 EXPORT_SYMBOL_GPL(sk_clone);
2617 
2618 static u32 sk_dst_gso_max_size(struct sock *sk, const struct net_device *dev)
2619 {
2620 	bool is_ipv6 = false;
2621 	u32 max_size;
2622 
2623 #if IS_ENABLED(CONFIG_IPV6)
2624 	is_ipv6 = (sk->sk_family == AF_INET6 &&
2625 		   !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2626 #endif
2627 	/* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2628 	max_size = is_ipv6 ? READ_ONCE(dev->gso_max_size) :
2629 			READ_ONCE(dev->gso_ipv4_max_size);
2630 	if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2631 		max_size = GSO_LEGACY_MAX_SIZE;
2632 
2633 	return max_size - (MAX_TCP_HEADER + 1);
2634 }
2635 
2636 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2637 {
2638 	const struct net_device *dev;
2639 	u32 max_segs = 1;
2640 
2641 	rcu_read_lock();
2642 	dev = dst_dev_rcu(dst);
2643 	sk->sk_route_caps = dev->features;
2644 	if (sk_is_tcp(sk)) {
2645 		struct inet_connection_sock *icsk = inet_csk(sk);
2646 
2647 		sk->sk_route_caps |= NETIF_F_GSO;
2648 		icsk->icsk_ack.dst_quick_ack = dst_metric(dst, RTAX_QUICKACK);
2649 	}
2650 	if (sk->sk_route_caps & NETIF_F_GSO)
2651 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2652 	if (unlikely(sk->sk_gso_disabled))
2653 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2654 	if (sk_can_gso(sk)) {
2655 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2656 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2657 		} else {
2658 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2659 			sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dev);
2660 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2661 			max_segs = max_t(u32, READ_ONCE(dev->gso_max_segs), 1);
2662 		}
2663 	}
2664 	sk->sk_gso_max_segs = max_segs;
2665 	sk_dst_set(sk, dst);
2666 	rcu_read_unlock();
2667 }
2668 EXPORT_SYMBOL_GPL(sk_setup_caps);
2669 
2670 /*
2671  *	Simple resource managers for sockets.
2672  */
2673 
2674 
2675 /*
2676  * Write buffer destructor automatically called from kfree_skb.
2677  */
2678 void sock_wfree(struct sk_buff *skb)
2679 {
2680 	unsigned int len = skb->truesize;
2681 	struct sock *sk = skb->sk;
2682 	bool free;
2683 	int old;
2684 
2685 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2686 		void (*sk_write_space)(struct sock *sk);
2687 
2688 		sk_write_space = READ_ONCE(sk->sk_write_space);
2689 
2690 		if (sock_flag(sk, SOCK_RCU_FREE) &&
2691 		    sk_write_space == sock_def_write_space) {
2692 			rcu_read_lock();
2693 			free = __refcount_sub_and_test(len, &sk->sk_wmem_alloc,
2694 						       &old);
2695 			sock_def_write_space_wfree(sk, old - len);
2696 			rcu_read_unlock();
2697 			if (unlikely(free))
2698 				__sk_free(sk);
2699 			return;
2700 		}
2701 
2702 		/*
2703 		 * Keep a reference on sk_wmem_alloc, this will be released
2704 		 * after sk_write_space() call
2705 		 */
2706 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2707 		sk_write_space(sk);
2708 		len = 1;
2709 	}
2710 	/*
2711 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2712 	 * could not do because of in-flight packets
2713 	 */
2714 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2715 		__sk_free(sk);
2716 }
2717 EXPORT_SYMBOL(sock_wfree);
2718 
2719 /* This variant of sock_wfree() is used by TCP,
2720  * since it sets SOCK_USE_WRITE_QUEUE.
2721  */
2722 #ifdef CONFIG_INET
2723 void __sock_wfree(struct sk_buff *skb)
2724 {
2725 	struct sock *sk = skb->sk;
2726 
2727 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2728 		__sk_free(sk);
2729 }
2730 EXPORT_SYMBOL_GPL(__sock_wfree);
2731 #endif
2732 
2733 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2734 {
2735 	int old_wmem;
2736 
2737 	skb_orphan(skb);
2738 #ifdef CONFIG_INET
2739 	if (unlikely(!sk_fullsock(sk)))
2740 		return skb_set_owner_edemux(skb, sk);
2741 #endif
2742 	skb->sk = sk;
2743 	skb->destructor = sock_wfree;
2744 	skb_set_hash_from_sk(skb, sk);
2745 	/*
2746 	 * We used to take a refcount on sk, but following operation
2747 	 * is enough to guarantee sk_free() won't free this sock until
2748 	 * all in-flight packets are completed
2749 	 */
2750 	__refcount_add(skb->truesize, &sk->sk_wmem_alloc, &old_wmem);
2751 
2752 	/* (old_wmem == SK_WMEM_ALLOC_BIAS) if no other TX packet for this socket
2753 	 * is in a host queue (qdisc, NIC queue).
2754 	 * Set skb->ooo_okay so that netdev_pick_tx() can choose a TX queue
2755 	 * based on XPS for better performance.
2756 	 * Otherwise clear ooo_okay to not risk Out Of Order delivery.
2757 	 */
2758 	skb->ooo_okay = (old_wmem == SK_WMEM_ALLOC_BIAS);
2759 }
2760 EXPORT_SYMBOL(skb_set_owner_w);
2761 
2762 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2763 {
2764 	/* Drivers depend on in-order delivery for crypto offload,
2765 	 * partial orphan breaks out-of-order-OK logic.
2766 	 */
2767 	if (skb_is_decrypted(skb))
2768 		return false;
2769 
2770 	return (skb->destructor == sock_wfree ||
2771 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2772 }
2773 
2774 /* This helper is used by netem, as it can hold packets in its
2775  * delay queue. We want to allow the owner socket to send more
2776  * packets, as if they were already TX completed by a typical driver.
2777  * But we also want to keep skb->sk set because some packet schedulers
2778  * rely on it (sch_fq for example).
2779  */
2780 void skb_orphan_partial(struct sk_buff *skb)
2781 {
2782 	if (skb_is_tcp_pure_ack(skb))
2783 		return;
2784 
2785 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2786 		return;
2787 
2788 	skb_orphan(skb);
2789 }
2790 EXPORT_SYMBOL(skb_orphan_partial);
2791 
2792 /*
2793  * Read buffer destructor automatically called from kfree_skb.
2794  */
2795 void sock_rfree(struct sk_buff *skb)
2796 {
2797 	struct sock *sk = skb->sk;
2798 	unsigned int len = skb->truesize;
2799 
2800 	atomic_sub(len, &sk->sk_rmem_alloc);
2801 	sk_mem_uncharge(sk, len);
2802 }
2803 EXPORT_SYMBOL(sock_rfree);
2804 
2805 /*
2806  * Buffer destructor for skbs that are not used directly in read or write
2807  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2808  */
2809 void sock_efree(struct sk_buff *skb)
2810 {
2811 	sock_put(skb->sk);
2812 }
2813 EXPORT_SYMBOL(sock_efree);
2814 
2815 /* Buffer destructor for prefetch/receive path where reference count may
2816  * not be held, e.g. for listen sockets.
2817  */
2818 #ifdef CONFIG_INET
2819 void sock_pfree(struct sk_buff *skb)
2820 {
2821 	struct sock *sk = skb->sk;
2822 
2823 	if (!sk_is_refcounted(sk))
2824 		return;
2825 
2826 	if (sk->sk_state == TCP_NEW_SYN_RECV && inet_reqsk(sk)->syncookie) {
2827 		inet_reqsk(sk)->rsk_listener = NULL;
2828 		reqsk_free(inet_reqsk(sk));
2829 		return;
2830 	}
2831 
2832 	sock_gen_put(sk);
2833 }
2834 EXPORT_SYMBOL(sock_pfree);
2835 #endif /* CONFIG_INET */
2836 
2837 /*
2838  * Allocate a skb from the socket's send buffer.
2839  */
2840 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2841 			     gfp_t priority)
2842 {
2843 	if (force ||
2844 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2845 		struct sk_buff *skb = alloc_skb(size, priority);
2846 
2847 		if (skb) {
2848 			skb_set_owner_w(skb, sk);
2849 			return skb;
2850 		}
2851 	}
2852 	return NULL;
2853 }
2854 EXPORT_SYMBOL(sock_wmalloc);
2855 
2856 static void sock_ofree(struct sk_buff *skb)
2857 {
2858 	struct sock *sk = skb->sk;
2859 
2860 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2861 }
2862 
2863 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2864 			     gfp_t priority)
2865 {
2866 	struct sk_buff *skb;
2867 
2868 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2869 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2870 	    READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2871 		return NULL;
2872 
2873 	skb = alloc_skb(size, priority);
2874 	if (!skb)
2875 		return NULL;
2876 
2877 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2878 	skb->sk = sk;
2879 	skb->destructor = sock_ofree;
2880 	return skb;
2881 }
2882 
2883 /*
2884  * Allocate a memory block from the socket's option memory buffer.
2885  */
2886 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2887 {
2888 	int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2889 
2890 	if ((unsigned int)size <= optmem_max &&
2891 	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2892 		void *mem;
2893 		/* First do the add, to avoid the race if kmalloc
2894 		 * might sleep.
2895 		 */
2896 		atomic_add(size, &sk->sk_omem_alloc);
2897 		mem = kmalloc(size, priority);
2898 		if (mem)
2899 			return mem;
2900 		atomic_sub(size, &sk->sk_omem_alloc);
2901 	}
2902 	return NULL;
2903 }
2904 EXPORT_SYMBOL(sock_kmalloc);
2905 
2906 /*
2907  * Duplicate the input "src" memory block using the socket's
2908  * option memory buffer.
2909  */
2910 void *sock_kmemdup(struct sock *sk, const void *src,
2911 		   int size, gfp_t priority)
2912 {
2913 	void *mem;
2914 
2915 	mem = sock_kmalloc(sk, size, priority);
2916 	if (mem)
2917 		memcpy(mem, src, size);
2918 	return mem;
2919 }
2920 EXPORT_SYMBOL(sock_kmemdup);
2921 
2922 /* Free an option memory block. Note, we actually want the inline
2923  * here as this allows gcc to detect the nullify and fold away the
2924  * condition entirely.
2925  */
2926 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2927 				  const bool nullify)
2928 {
2929 	if (WARN_ON_ONCE(!mem))
2930 		return;
2931 	if (nullify)
2932 		kfree_sensitive(mem);
2933 	else
2934 		kfree(mem);
2935 	atomic_sub(size, &sk->sk_omem_alloc);
2936 }
2937 
2938 void sock_kfree_s(struct sock *sk, void *mem, int size)
2939 {
2940 	__sock_kfree_s(sk, mem, size, false);
2941 }
2942 EXPORT_SYMBOL(sock_kfree_s);
2943 
2944 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2945 {
2946 	__sock_kfree_s(sk, mem, size, true);
2947 }
2948 EXPORT_SYMBOL(sock_kzfree_s);
2949 
2950 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2951    I think, these locks should be removed for datagram sockets.
2952  */
2953 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2954 {
2955 	DEFINE_WAIT(wait);
2956 
2957 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2958 	for (;;) {
2959 		if (!timeo)
2960 			break;
2961 		if (signal_pending(current))
2962 			break;
2963 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2964 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2965 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2966 			break;
2967 		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2968 			break;
2969 		if (READ_ONCE(sk->sk_err))
2970 			break;
2971 		timeo = schedule_timeout(timeo);
2972 	}
2973 	finish_wait(sk_sleep(sk), &wait);
2974 	return timeo;
2975 }
2976 
2977 
2978 /*
2979  *	Generic send/receive buffer handlers
2980  */
2981 
2982 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2983 				     unsigned long data_len, int noblock,
2984 				     int *errcode, int max_page_order)
2985 {
2986 	struct sk_buff *skb;
2987 	long timeo;
2988 	int err;
2989 
2990 	timeo = sock_sndtimeo(sk, noblock);
2991 	for (;;) {
2992 		err = sock_error(sk);
2993 		if (err != 0)
2994 			goto failure;
2995 
2996 		err = -EPIPE;
2997 		if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2998 			goto failure;
2999 
3000 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
3001 			break;
3002 
3003 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
3004 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
3005 		err = -EAGAIN;
3006 		if (!timeo)
3007 			goto failure;
3008 		if (signal_pending(current))
3009 			goto interrupted;
3010 		timeo = sock_wait_for_wmem(sk, timeo);
3011 	}
3012 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
3013 				   errcode, sk->sk_allocation);
3014 	if (skb)
3015 		skb_set_owner_w(skb, sk);
3016 	return skb;
3017 
3018 interrupted:
3019 	err = sock_intr_errno(timeo);
3020 failure:
3021 	*errcode = err;
3022 	return NULL;
3023 }
3024 EXPORT_SYMBOL(sock_alloc_send_pskb);
3025 
3026 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
3027 		     struct sockcm_cookie *sockc)
3028 {
3029 	u32 tsflags;
3030 
3031 	BUILD_BUG_ON(SOF_TIMESTAMPING_LAST == (1 << 31));
3032 
3033 	switch (cmsg->cmsg_type) {
3034 	case SO_MARK:
3035 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
3036 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
3037 			return -EPERM;
3038 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3039 			return -EINVAL;
3040 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
3041 		break;
3042 	case SO_TIMESTAMPING_OLD:
3043 	case SO_TIMESTAMPING_NEW:
3044 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3045 			return -EINVAL;
3046 
3047 		tsflags = *(u32 *)CMSG_DATA(cmsg);
3048 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
3049 			return -EINVAL;
3050 
3051 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
3052 		sockc->tsflags |= tsflags;
3053 		break;
3054 	case SCM_TXTIME:
3055 	{
3056 		ktime_t tmin;
3057 		u64 txtime;
3058 
3059 		if (!sock_flag(sk, SOCK_TXTIME))
3060 			return -EINVAL;
3061 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
3062 			return -EINVAL;
3063 
3064 		txtime = get_unaligned((u64 *)CMSG_DATA(cmsg));
3065 
3066 		/* Allow sending without a delivery time: zero special case */
3067 		if (!txtime) {
3068 			sockc->transmit_time = 0;
3069 			break;
3070 		}
3071 
3072 		switch (sk->sk_clockid) {
3073 		case CLOCK_MONOTONIC:
3074 			tmin = 1;
3075 			break;
3076 		case CLOCK_REALTIME:
3077 			tmin = max(ktime_mono_to_real(0), 1);
3078 			break;
3079 		case CLOCK_TAI:
3080 			tmin = max(ktime_mono_to_any(0, TK_OFFS_TAI), 1);
3081 			break;
3082 		default:
3083 			tmin = 1;
3084 			WARN_ON_ONCE(1);
3085 			break;
3086 		}
3087 
3088 		sockc->transmit_time = max_t(ktime_t, txtime, tmin);
3089 		break;
3090 	}
3091 	case SCM_TS_OPT_ID:
3092 		if (sk_is_tcp(sk))
3093 			return -EINVAL;
3094 		tsflags = READ_ONCE(sk->sk_tsflags);
3095 		if (!(tsflags & SOF_TIMESTAMPING_OPT_ID))
3096 			return -EINVAL;
3097 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3098 			return -EINVAL;
3099 		sockc->ts_opt_id = *(u32 *)CMSG_DATA(cmsg);
3100 		sockc->tsflags |= SOCKCM_FLAG_TS_OPT_ID;
3101 		break;
3102 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
3103 	case SCM_RIGHTS:
3104 	case SCM_CREDENTIALS:
3105 		break;
3106 	case SO_PRIORITY:
3107 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3108 			return -EINVAL;
3109 		if (!sk_set_prio_allowed(sk, *(u32 *)CMSG_DATA(cmsg)))
3110 			return -EPERM;
3111 		sockc->priority = *(u32 *)CMSG_DATA(cmsg);
3112 		break;
3113 	case SCM_DEVMEM_DMABUF:
3114 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3115 			return -EINVAL;
3116 		sockc->dmabuf_id = *(u32 *)CMSG_DATA(cmsg);
3117 		break;
3118 	default:
3119 		return -EINVAL;
3120 	}
3121 	return 0;
3122 }
3123 EXPORT_SYMBOL(__sock_cmsg_send);
3124 
3125 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
3126 		   struct sockcm_cookie *sockc)
3127 {
3128 	struct cmsghdr *cmsg;
3129 	int ret;
3130 
3131 	for_each_cmsghdr(cmsg, msg) {
3132 		if (!CMSG_OK(msg, cmsg))
3133 			return -EINVAL;
3134 		if (cmsg->cmsg_level != SOL_SOCKET)
3135 			continue;
3136 		ret = __sock_cmsg_send(sk, cmsg, sockc);
3137 		if (ret)
3138 			return ret;
3139 	}
3140 	return 0;
3141 }
3142 EXPORT_SYMBOL(sock_cmsg_send);
3143 
3144 static void sk_enter_memory_pressure(struct sock *sk)
3145 {
3146 	if (!sk->sk_prot->enter_memory_pressure)
3147 		return;
3148 
3149 	sk->sk_prot->enter_memory_pressure(sk);
3150 }
3151 
3152 static void sk_leave_memory_pressure(struct sock *sk)
3153 {
3154 	if (sk->sk_prot->leave_memory_pressure) {
3155 		INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
3156 				     tcp_leave_memory_pressure, sk);
3157 	} else {
3158 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
3159 
3160 		if (memory_pressure && READ_ONCE(*memory_pressure))
3161 			WRITE_ONCE(*memory_pressure, 0);
3162 	}
3163 }
3164 
3165 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
3166 
3167 /**
3168  * skb_page_frag_refill - check that a page_frag contains enough room
3169  * @sz: minimum size of the fragment we want to get
3170  * @pfrag: pointer to page_frag
3171  * @gfp: priority for memory allocation
3172  *
3173  * Note: While this allocator tries to use high order pages, there is
3174  * no guarantee that allocations succeed. Therefore, @sz MUST be
3175  * less or equal than PAGE_SIZE.
3176  */
3177 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
3178 {
3179 	if (pfrag->page) {
3180 		if (page_ref_count(pfrag->page) == 1) {
3181 			pfrag->offset = 0;
3182 			return true;
3183 		}
3184 		if (pfrag->offset + sz <= pfrag->size)
3185 			return true;
3186 		put_page(pfrag->page);
3187 	}
3188 
3189 	pfrag->offset = 0;
3190 	if (SKB_FRAG_PAGE_ORDER &&
3191 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
3192 		/* Avoid direct reclaim but allow kswapd to wake */
3193 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
3194 					  __GFP_COMP | __GFP_NOWARN |
3195 					  __GFP_NORETRY,
3196 					  SKB_FRAG_PAGE_ORDER);
3197 		if (likely(pfrag->page)) {
3198 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
3199 			return true;
3200 		}
3201 	}
3202 	pfrag->page = alloc_page(gfp);
3203 	if (likely(pfrag->page)) {
3204 		pfrag->size = PAGE_SIZE;
3205 		return true;
3206 	}
3207 	return false;
3208 }
3209 EXPORT_SYMBOL(skb_page_frag_refill);
3210 
3211 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
3212 {
3213 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
3214 		return true;
3215 
3216 	if (!sk->sk_bypass_prot_mem)
3217 		sk_enter_memory_pressure(sk);
3218 
3219 	sk_stream_moderate_sndbuf(sk);
3220 
3221 	return false;
3222 }
3223 EXPORT_SYMBOL(sk_page_frag_refill);
3224 
3225 static void __lock_sock(struct sock *sk)
3226 	__releases(&sk->sk_lock.slock)
3227 	__acquires(&sk->sk_lock.slock)
3228 {
3229 	DEFINE_WAIT(wait);
3230 
3231 	for (;;) {
3232 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
3233 					TASK_UNINTERRUPTIBLE);
3234 		spin_unlock_bh(&sk->sk_lock.slock);
3235 		schedule();
3236 		spin_lock_bh(&sk->sk_lock.slock);
3237 		if (!sock_owned_by_user(sk))
3238 			break;
3239 	}
3240 	finish_wait(&sk->sk_lock.wq, &wait);
3241 }
3242 
3243 void __release_sock(struct sock *sk)
3244 	__releases(&sk->sk_lock.slock)
3245 	__acquires(&sk->sk_lock.slock)
3246 {
3247 	struct sk_buff *skb, *next;
3248 	int nb = 0;
3249 
3250 	while ((skb = sk->sk_backlog.head) != NULL) {
3251 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
3252 
3253 		spin_unlock_bh(&sk->sk_lock.slock);
3254 
3255 		while (1) {
3256 			next = skb->next;
3257 			prefetch(next);
3258 			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
3259 			skb_mark_not_on_list(skb);
3260 			sk_backlog_rcv(sk, skb);
3261 
3262 			skb = next;
3263 			if (!skb)
3264 				break;
3265 
3266 			if (!(++nb & 15))
3267 				cond_resched();
3268 		}
3269 
3270 		spin_lock_bh(&sk->sk_lock.slock);
3271 	}
3272 
3273 	/*
3274 	 * Doing the zeroing here guarantee we can not loop forever
3275 	 * while a wild producer attempts to flood us.
3276 	 */
3277 	sk->sk_backlog.len = 0;
3278 }
3279 
3280 void __sk_flush_backlog(struct sock *sk)
3281 {
3282 	spin_lock_bh(&sk->sk_lock.slock);
3283 	__release_sock(sk);
3284 
3285 	if (sk->sk_prot->release_cb)
3286 		INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3287 				     tcp_release_cb, sk);
3288 
3289 	spin_unlock_bh(&sk->sk_lock.slock);
3290 }
3291 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3292 
3293 /**
3294  * sk_wait_data - wait for data to arrive at sk_receive_queue
3295  * @sk:    sock to wait on
3296  * @timeo: for how long
3297  * @skb:   last skb seen on sk_receive_queue
3298  *
3299  * Now socket state including sk->sk_err is changed only under lock,
3300  * hence we may omit checks after joining wait queue.
3301  * We check receive queue before schedule() only as optimization;
3302  * it is very likely that release_sock() added new data.
3303  */
3304 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3305 {
3306 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
3307 	int rc;
3308 
3309 	add_wait_queue(sk_sleep(sk), &wait);
3310 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3311 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3312 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3313 	remove_wait_queue(sk_sleep(sk), &wait);
3314 	return rc;
3315 }
3316 EXPORT_SYMBOL(sk_wait_data);
3317 
3318 /**
3319  *	__sk_mem_raise_allocated - increase memory_allocated
3320  *	@sk: socket
3321  *	@size: memory size to allocate
3322  *	@amt: pages to allocate
3323  *	@kind: allocation type
3324  *
3325  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3326  *
3327  *	Unlike the globally shared limits among the sockets under same protocol,
3328  *	consuming the budget of a memcg won't have direct effect on other ones.
3329  *	So be optimistic about memcg's tolerance, and leave the callers to decide
3330  *	whether or not to raise allocated through sk_under_memory_pressure() or
3331  *	its variants.
3332  */
3333 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3334 {
3335 	bool memcg_enabled = false, charged = false;
3336 	struct proto *prot = sk->sk_prot;
3337 	long allocated = 0;
3338 
3339 	if (!sk->sk_bypass_prot_mem) {
3340 		sk_memory_allocated_add(sk, amt);
3341 		allocated = sk_memory_allocated(sk);
3342 	}
3343 
3344 	if (mem_cgroup_sk_enabled(sk)) {
3345 		memcg_enabled = true;
3346 		charged = mem_cgroup_sk_charge(sk, amt, gfp_memcg_charge());
3347 		if (!charged)
3348 			goto suppress_allocation;
3349 	}
3350 
3351 	if (!allocated)
3352 		return 1;
3353 
3354 	/* Under limit. */
3355 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
3356 		sk_leave_memory_pressure(sk);
3357 		return 1;
3358 	}
3359 
3360 	/* Under pressure. */
3361 	if (allocated > sk_prot_mem_limits(sk, 1))
3362 		sk_enter_memory_pressure(sk);
3363 
3364 	/* Over hard limit. */
3365 	if (allocated > sk_prot_mem_limits(sk, 2))
3366 		goto suppress_allocation;
3367 
3368 	/* Guarantee minimum buffer size under pressure (either global
3369 	 * or memcg) to make sure features described in RFC 7323 (TCP
3370 	 * Extensions for High Performance) work properly.
3371 	 *
3372 	 * This rule does NOT stand when exceeds global or memcg's hard
3373 	 * limit, or else a DoS attack can be taken place by spawning
3374 	 * lots of sockets whose usage are under minimum buffer size.
3375 	 */
3376 	if (kind == SK_MEM_RECV) {
3377 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3378 			return 1;
3379 
3380 	} else { /* SK_MEM_SEND */
3381 		int wmem0 = sk_get_wmem0(sk, prot);
3382 
3383 		if (sk->sk_type == SOCK_STREAM) {
3384 			if (sk->sk_wmem_queued < wmem0)
3385 				return 1;
3386 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3387 				return 1;
3388 		}
3389 	}
3390 
3391 	if (sk_has_memory_pressure(sk)) {
3392 		u64 alloc;
3393 
3394 		/* The following 'average' heuristic is within the
3395 		 * scope of global accounting, so it only makes
3396 		 * sense for global memory pressure.
3397 		 */
3398 		if (!sk_under_global_memory_pressure(sk))
3399 			return 1;
3400 
3401 		/* Try to be fair among all the sockets under global
3402 		 * pressure by allowing the ones that below average
3403 		 * usage to raise.
3404 		 */
3405 		alloc = sk_sockets_allocated_read_positive(sk);
3406 		if (sk_prot_mem_limits(sk, 2) > alloc *
3407 		    sk_mem_pages(sk->sk_wmem_queued +
3408 				 atomic_read(&sk->sk_rmem_alloc) +
3409 				 sk->sk_forward_alloc))
3410 			return 1;
3411 	}
3412 
3413 suppress_allocation:
3414 
3415 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3416 		sk_stream_moderate_sndbuf(sk);
3417 
3418 		/* Fail only if socket is _under_ its sndbuf.
3419 		 * In this case we cannot block, so that we have to fail.
3420 		 */
3421 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3422 			/* Force charge with __GFP_NOFAIL */
3423 			if (memcg_enabled && !charged)
3424 				mem_cgroup_sk_charge(sk, amt,
3425 						     gfp_memcg_charge() | __GFP_NOFAIL);
3426 			return 1;
3427 		}
3428 	}
3429 
3430 	trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3431 
3432 	if (allocated)
3433 		sk_memory_allocated_sub(sk, amt);
3434 
3435 	if (charged)
3436 		mem_cgroup_sk_uncharge(sk, amt);
3437 
3438 	return 0;
3439 }
3440 
3441 /**
3442  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3443  *	@sk: socket
3444  *	@size: memory size to allocate
3445  *	@kind: allocation type
3446  *
3447  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3448  *	rmem allocation. This function assumes that protocols which have
3449  *	memory_pressure use sk_wmem_queued as write buffer accounting.
3450  */
3451 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3452 {
3453 	int ret, amt = sk_mem_pages(size);
3454 
3455 	sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3456 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3457 	if (!ret)
3458 		sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3459 	return ret;
3460 }
3461 EXPORT_SYMBOL(__sk_mem_schedule);
3462 
3463 /**
3464  *	__sk_mem_reduce_allocated - reclaim memory_allocated
3465  *	@sk: socket
3466  *	@amount: number of quanta
3467  *
3468  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3469  */
3470 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3471 {
3472 	if (mem_cgroup_sk_enabled(sk))
3473 		mem_cgroup_sk_uncharge(sk, amount);
3474 
3475 	if (sk->sk_bypass_prot_mem)
3476 		return;
3477 
3478 	sk_memory_allocated_sub(sk, amount);
3479 
3480 	if (sk_under_global_memory_pressure(sk) &&
3481 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3482 		sk_leave_memory_pressure(sk);
3483 }
3484 
3485 /**
3486  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3487  *	@sk: socket
3488  *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3489  */
3490 void __sk_mem_reclaim(struct sock *sk, int amount)
3491 {
3492 	amount >>= PAGE_SHIFT;
3493 	sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3494 	__sk_mem_reduce_allocated(sk, amount);
3495 }
3496 EXPORT_SYMBOL(__sk_mem_reclaim);
3497 
3498 void __sk_charge(struct sock *sk, gfp_t gfp)
3499 {
3500 	int amt;
3501 
3502 	gfp |= __GFP_NOFAIL;
3503 	if (mem_cgroup_from_sk(sk)) {
3504 		/* The socket has not been accepted yet, no need
3505 		 * to look at newsk->sk_wmem_queued.
3506 		 */
3507 		amt = sk_mem_pages(sk->sk_forward_alloc +
3508 				   atomic_read(&sk->sk_rmem_alloc));
3509 		if (amt)
3510 			mem_cgroup_sk_charge(sk, amt, gfp);
3511 	}
3512 
3513 	kmem_cache_charge(sk, gfp);
3514 }
3515 
3516 int sk_set_peek_off(struct sock *sk, int val)
3517 {
3518 	WRITE_ONCE(sk->sk_peek_off, val);
3519 	return 0;
3520 }
3521 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3522 
3523 /*
3524  * Set of default routines for initialising struct proto_ops when
3525  * the protocol does not support a particular function. In certain
3526  * cases where it makes no sense for a protocol to have a "do nothing"
3527  * function, some default processing is provided.
3528  */
3529 
3530 int sock_no_bind(struct socket *sock, struct sockaddr_unsized *saddr, int len)
3531 {
3532 	return -EOPNOTSUPP;
3533 }
3534 EXPORT_SYMBOL(sock_no_bind);
3535 
3536 int sock_no_connect(struct socket *sock, struct sockaddr_unsized *saddr,
3537 		    int len, int flags)
3538 {
3539 	return -EOPNOTSUPP;
3540 }
3541 EXPORT_SYMBOL(sock_no_connect);
3542 
3543 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3544 {
3545 	return -EOPNOTSUPP;
3546 }
3547 EXPORT_SYMBOL(sock_no_socketpair);
3548 
3549 int sock_no_accept(struct socket *sock, struct socket *newsock,
3550 		   struct proto_accept_arg *arg)
3551 {
3552 	return -EOPNOTSUPP;
3553 }
3554 EXPORT_SYMBOL(sock_no_accept);
3555 
3556 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3557 		    int peer)
3558 {
3559 	return -EOPNOTSUPP;
3560 }
3561 EXPORT_SYMBOL(sock_no_getname);
3562 
3563 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3564 {
3565 	return -EOPNOTSUPP;
3566 }
3567 EXPORT_SYMBOL(sock_no_ioctl);
3568 
3569 int sock_no_listen(struct socket *sock, int backlog)
3570 {
3571 	return -EOPNOTSUPP;
3572 }
3573 EXPORT_SYMBOL(sock_no_listen);
3574 
3575 int sock_no_shutdown(struct socket *sock, int how)
3576 {
3577 	return -EOPNOTSUPP;
3578 }
3579 EXPORT_SYMBOL(sock_no_shutdown);
3580 
3581 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3582 {
3583 	return -EOPNOTSUPP;
3584 }
3585 EXPORT_SYMBOL(sock_no_sendmsg);
3586 
3587 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3588 {
3589 	return -EOPNOTSUPP;
3590 }
3591 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3592 
3593 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3594 		    int flags)
3595 {
3596 	return -EOPNOTSUPP;
3597 }
3598 EXPORT_SYMBOL(sock_no_recvmsg);
3599 
3600 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3601 {
3602 	/* Mirror missing mmap method error code */
3603 	return -ENODEV;
3604 }
3605 EXPORT_SYMBOL(sock_no_mmap);
3606 
3607 /*
3608  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3609  * various sock-based usage counts.
3610  */
3611 void __receive_sock(struct file *file)
3612 {
3613 	struct socket *sock;
3614 
3615 	sock = sock_from_file(file);
3616 	if (sock) {
3617 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3618 		sock_update_classid(&sock->sk->sk_cgrp_data);
3619 	}
3620 }
3621 
3622 /*
3623  *	Default Socket Callbacks
3624  */
3625 
3626 static void sock_def_wakeup(struct sock *sk)
3627 {
3628 	struct socket_wq *wq;
3629 
3630 	rcu_read_lock();
3631 	wq = rcu_dereference(sk->sk_wq);
3632 	if (skwq_has_sleeper(wq))
3633 		wake_up_interruptible_all(&wq->wait);
3634 	rcu_read_unlock();
3635 }
3636 
3637 static void sock_def_error_report(struct sock *sk)
3638 {
3639 	struct socket_wq *wq;
3640 
3641 	rcu_read_lock();
3642 	wq = rcu_dereference(sk->sk_wq);
3643 	if (skwq_has_sleeper(wq))
3644 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3645 	sk_wake_async_rcu(sk, SOCK_WAKE_IO, POLL_ERR);
3646 	rcu_read_unlock();
3647 }
3648 
3649 void sock_def_readable(struct sock *sk)
3650 {
3651 	struct socket_wq *wq;
3652 
3653 	trace_sk_data_ready(sk);
3654 
3655 	rcu_read_lock();
3656 	wq = rcu_dereference(sk->sk_wq);
3657 	if (skwq_has_sleeper(wq))
3658 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3659 						EPOLLRDNORM | EPOLLRDBAND);
3660 	sk_wake_async_rcu(sk, SOCK_WAKE_WAITD, POLL_IN);
3661 	rcu_read_unlock();
3662 }
3663 
3664 static void sock_def_write_space(struct sock *sk)
3665 {
3666 	struct socket_wq *wq;
3667 
3668 	rcu_read_lock();
3669 
3670 	/* Do not wake up a writer until he can make "significant"
3671 	 * progress.  --DaveM
3672 	 */
3673 	if (sock_writeable(sk)) {
3674 		wq = rcu_dereference(sk->sk_wq);
3675 		if (skwq_has_sleeper(wq))
3676 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3677 						EPOLLWRNORM | EPOLLWRBAND);
3678 
3679 		/* Should agree with poll, otherwise some programs break */
3680 		sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3681 	}
3682 
3683 	rcu_read_unlock();
3684 }
3685 
3686 /* An optimised version of sock_def_write_space(), should only be called
3687  * for SOCK_RCU_FREE sockets under RCU read section and after putting
3688  * ->sk_wmem_alloc.
3689  */
3690 static void sock_def_write_space_wfree(struct sock *sk, int wmem_alloc)
3691 {
3692 	/* Do not wake up a writer until he can make "significant"
3693 	 * progress.  --DaveM
3694 	 */
3695 	if (__sock_writeable(sk, wmem_alloc)) {
3696 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3697 
3698 		/* rely on refcount_sub from sock_wfree() */
3699 		smp_mb__after_atomic();
3700 		if (wq && waitqueue_active(&wq->wait))
3701 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3702 						EPOLLWRNORM | EPOLLWRBAND);
3703 
3704 		/* Should agree with poll, otherwise some programs break */
3705 		sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3706 	}
3707 }
3708 
3709 static void sock_def_destruct(struct sock *sk)
3710 {
3711 }
3712 
3713 void sk_send_sigurg(struct sock *sk)
3714 {
3715 	if (sk->sk_socket && sk->sk_socket->file)
3716 		if (send_sigurg(sk->sk_socket->file))
3717 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3718 }
3719 EXPORT_SYMBOL(sk_send_sigurg);
3720 
3721 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3722 		    unsigned long expires)
3723 {
3724 	if (!mod_timer(timer, expires))
3725 		sock_hold(sk);
3726 }
3727 EXPORT_SYMBOL(sk_reset_timer);
3728 
3729 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3730 {
3731 	if (timer_delete(timer))
3732 		__sock_put(sk);
3733 }
3734 EXPORT_SYMBOL(sk_stop_timer);
3735 
3736 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3737 {
3738 	if (timer_delete_sync(timer))
3739 		__sock_put(sk);
3740 }
3741 EXPORT_SYMBOL(sk_stop_timer_sync);
3742 
3743 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3744 {
3745 	sk_init_common(sk);
3746 	sk->sk_send_head	=	NULL;
3747 
3748 	timer_setup(&sk->sk_timer, NULL, 0);
3749 
3750 	sk->sk_allocation	=	GFP_KERNEL;
3751 	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3752 	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3753 	sk->sk_state		=	TCP_CLOSE;
3754 	sk->sk_use_task_frag	=	true;
3755 	sk_set_socket(sk, sock);
3756 
3757 	sock_set_flag(sk, SOCK_ZAPPED);
3758 
3759 	if (sock) {
3760 		sk->sk_type	=	sock->type;
3761 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3762 		sock->sk	=	sk;
3763 	} else {
3764 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3765 	}
3766 	sk->sk_uid	=	uid;
3767 
3768 	sk->sk_state_change	=	sock_def_wakeup;
3769 	sk->sk_data_ready	=	sock_def_readable;
3770 	sk->sk_write_space	=	sock_def_write_space;
3771 	sk->sk_error_report	=	sock_def_error_report;
3772 	sk->sk_destruct		=	sock_def_destruct;
3773 
3774 	sk->sk_frag.page	=	NULL;
3775 	sk->sk_frag.offset	=	0;
3776 	sk->sk_peek_off		=	-1;
3777 
3778 	sk->sk_peer_pid 	=	NULL;
3779 	sk->sk_peer_cred	=	NULL;
3780 	spin_lock_init(&sk->sk_peer_lock);
3781 
3782 	sk->sk_write_pending	=	0;
3783 	sk->sk_rcvlowat		=	1;
3784 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3785 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3786 
3787 	sk->sk_stamp = SK_DEFAULT_STAMP;
3788 #if BITS_PER_LONG==32
3789 	seqlock_init(&sk->sk_stamp_seq);
3790 #endif
3791 	atomic_set(&sk->sk_zckey, 0);
3792 
3793 #ifdef CONFIG_NET_RX_BUSY_POLL
3794 	sk->sk_napi_id		=	0;
3795 	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3796 #endif
3797 
3798 	sk->sk_max_pacing_rate = ~0UL;
3799 	sk->sk_pacing_rate = ~0UL;
3800 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3801 	sk->sk_incoming_cpu = -1;
3802 
3803 	sk_rx_queue_clear(sk);
3804 	/*
3805 	 * Before updating sk_refcnt, we must commit prior changes to memory
3806 	 * (Documentation/RCU/rculist_nulls.rst for details)
3807 	 */
3808 	smp_wmb();
3809 	refcount_set(&sk->sk_refcnt, 1);
3810 	sk_drops_reset(sk);
3811 }
3812 EXPORT_SYMBOL(sock_init_data_uid);
3813 
3814 void sock_init_data(struct socket *sock, struct sock *sk)
3815 {
3816 	kuid_t uid = sock ?
3817 		SOCK_INODE(sock)->i_uid :
3818 		make_kuid(sock_net(sk)->user_ns, 0);
3819 
3820 	sock_init_data_uid(sock, sk, uid);
3821 }
3822 EXPORT_SYMBOL(sock_init_data);
3823 
3824 void noinline lock_sock_nested(struct sock *sk, int subclass)
3825 {
3826 	/* The sk_lock has mutex_lock() semantics here. */
3827 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3828 
3829 	might_sleep();
3830 #ifdef CONFIG_64BIT
3831 	if (sizeof(struct slock_owned) == sizeof(long)) {
3832 		socket_lock_t tmp = {
3833 			.slock = __SPIN_LOCK_UNLOCKED(tmp.slock),
3834 			.owned = 1,
3835 		};
3836 		socket_lock_t old = {
3837 			.slock = __SPIN_LOCK_UNLOCKED(old.slock),
3838 			.owned = 0,
3839 		};
3840 
3841 		if (likely(try_cmpxchg(&sk->sk_lock.combined,
3842 				       &old.combined, tmp.combined)))
3843 			return;
3844 	}
3845 #endif
3846 	spin_lock_bh(&sk->sk_lock.slock);
3847 	if (unlikely(sock_owned_by_user_nocheck(sk)))
3848 		__lock_sock(sk);
3849 	sk->sk_lock.owned = 1;
3850 	spin_unlock_bh(&sk->sk_lock.slock);
3851 }
3852 EXPORT_SYMBOL(lock_sock_nested);
3853 
3854 void release_sock(struct sock *sk)
3855 {
3856 	spin_lock_bh(&sk->sk_lock.slock);
3857 
3858 	if (unlikely(sk->sk_backlog.tail))
3859 		__release_sock(sk);
3860 
3861 	if (sk->sk_prot->release_cb) {
3862 		if (!tcp_release_cb_cond(sk))
3863 			sk->sk_prot->release_cb(sk);
3864 	}
3865 	sock_release_ownership(sk);
3866 	if (unlikely(waitqueue_active(&sk->sk_lock.wq)))
3867 		wake_up(&sk->sk_lock.wq);
3868 
3869 	spin_unlock_bh(&sk->sk_lock.slock);
3870 }
3871 EXPORT_SYMBOL(release_sock);
3872 
3873 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3874 {
3875 	might_sleep();
3876 	spin_lock_bh(&sk->sk_lock.slock);
3877 
3878 	if (likely(!sock_owned_by_user_nocheck(sk))) {
3879 		/*
3880 		 * Fast path return with bottom halves disabled and
3881 		 * sock::sk_lock.slock held.
3882 		 *
3883 		 * The 'mutex' is not contended and holding
3884 		 * sock::sk_lock.slock prevents all other lockers to
3885 		 * proceed so the corresponding unlock_sock_fast() can
3886 		 * avoid the slow path of release_sock() completely and
3887 		 * just release slock.
3888 		 *
3889 		 * From a semantical POV this is equivalent to 'acquiring'
3890 		 * the 'mutex', hence the corresponding lockdep
3891 		 * mutex_release() has to happen in the fast path of
3892 		 * unlock_sock_fast().
3893 		 */
3894 		return false;
3895 	}
3896 
3897 	__lock_sock(sk);
3898 	sk->sk_lock.owned = 1;
3899 	__acquire(&sk->sk_lock.slock);
3900 	spin_unlock_bh(&sk->sk_lock.slock);
3901 	return true;
3902 }
3903 EXPORT_SYMBOL(__lock_sock_fast);
3904 
3905 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3906 		   bool timeval, bool time32)
3907 {
3908 	struct sock *sk = sock->sk;
3909 	struct timespec64 ts;
3910 
3911 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3912 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3913 	if (ts.tv_sec == -1)
3914 		return -ENOENT;
3915 	if (ts.tv_sec == 0) {
3916 		ktime_t kt = ktime_get_real();
3917 		sock_write_timestamp(sk, kt);
3918 		ts = ktime_to_timespec64(kt);
3919 	}
3920 
3921 	if (timeval)
3922 		ts.tv_nsec /= 1000;
3923 
3924 #ifdef CONFIG_COMPAT_32BIT_TIME
3925 	if (time32)
3926 		return put_old_timespec32(&ts, userstamp);
3927 #endif
3928 #ifdef CONFIG_SPARC64
3929 	/* beware of padding in sparc64 timeval */
3930 	if (timeval && !in_compat_syscall()) {
3931 		struct __kernel_old_timeval __user tv = {
3932 			.tv_sec = ts.tv_sec,
3933 			.tv_usec = ts.tv_nsec,
3934 		};
3935 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3936 			return -EFAULT;
3937 		return 0;
3938 	}
3939 #endif
3940 	return put_timespec64(&ts, userstamp);
3941 }
3942 EXPORT_SYMBOL(sock_gettstamp);
3943 
3944 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3945 {
3946 	if (!sock_flag(sk, flag)) {
3947 		unsigned long previous_flags = sk->sk_flags;
3948 
3949 		sock_set_flag(sk, flag);
3950 		/*
3951 		 * we just set one of the two flags which require net
3952 		 * time stamping, but time stamping might have been on
3953 		 * already because of the other one
3954 		 */
3955 		if (sock_needs_netstamp(sk) &&
3956 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3957 			net_enable_timestamp();
3958 	}
3959 }
3960 
3961 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3962 		       int level, int type)
3963 {
3964 	struct sock_extended_err ee;
3965 	struct sk_buff *skb;
3966 	int copied, err;
3967 
3968 	err = -EAGAIN;
3969 	skb = sock_dequeue_err_skb(sk);
3970 	if (skb == NULL)
3971 		goto out;
3972 
3973 	copied = skb->len;
3974 	if (copied > len) {
3975 		msg->msg_flags |= MSG_TRUNC;
3976 		copied = len;
3977 	}
3978 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3979 	if (err)
3980 		goto out_free_skb;
3981 
3982 	sock_recv_timestamp(msg, sk, skb);
3983 
3984 	/* We must use a bounce buffer for CONFIG_HARDENED_USERCOPY=y */
3985 	ee = SKB_EXT_ERR(skb)->ee;
3986 	put_cmsg(msg, level, type, sizeof(ee), &ee);
3987 
3988 	msg->msg_flags |= MSG_ERRQUEUE;
3989 	err = copied;
3990 
3991 out_free_skb:
3992 	kfree_skb(skb);
3993 out:
3994 	return err;
3995 }
3996 EXPORT_SYMBOL(sock_recv_errqueue);
3997 
3998 /*
3999  *	Get a socket option on an socket.
4000  *
4001  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
4002  *	asynchronous errors should be reported by getsockopt. We assume
4003  *	this means if you specify SO_ERROR (otherwise what is the point of it).
4004  */
4005 int sock_common_getsockopt(struct socket *sock, int level, int optname,
4006 			   char __user *optval, int __user *optlen)
4007 {
4008 	struct sock *sk = sock->sk;
4009 
4010 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
4011 	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
4012 }
4013 EXPORT_SYMBOL(sock_common_getsockopt);
4014 
4015 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
4016 			int flags)
4017 {
4018 	struct sock *sk = sock->sk;
4019 
4020 	return sk->sk_prot->recvmsg(sk, msg, size, flags);
4021 }
4022 EXPORT_SYMBOL(sock_common_recvmsg);
4023 
4024 /*
4025  *	Set socket options on an inet socket.
4026  */
4027 int sock_common_setsockopt(struct socket *sock, int level, int optname,
4028 			   sockptr_t optval, unsigned int optlen)
4029 {
4030 	struct sock *sk = sock->sk;
4031 
4032 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
4033 	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
4034 }
4035 EXPORT_SYMBOL(sock_common_setsockopt);
4036 
4037 void sk_common_release(struct sock *sk)
4038 {
4039 	if (sk->sk_prot->destroy)
4040 		sk->sk_prot->destroy(sk);
4041 
4042 	/*
4043 	 * Observation: when sk_common_release is called, processes have
4044 	 * no access to socket. But net still has.
4045 	 * Step one, detach it from networking:
4046 	 *
4047 	 * A. Remove from hash tables.
4048 	 */
4049 
4050 	sk->sk_prot->unhash(sk);
4051 
4052 	/*
4053 	 * In this point socket cannot receive new packets, but it is possible
4054 	 * that some packets are in flight because some CPU runs receiver and
4055 	 * did hash table lookup before we unhashed socket. They will achieve
4056 	 * receive queue and will be purged by socket destructor.
4057 	 *
4058 	 * Also we still have packets pending on receive queue and probably,
4059 	 * our own packets waiting in device queues. sock_destroy will drain
4060 	 * receive queue, but transmitted packets will delay socket destruction
4061 	 * until the last reference will be released.
4062 	 */
4063 
4064 	sock_orphan(sk);
4065 
4066 	xfrm_sk_free_policy(sk);
4067 
4068 	sock_put(sk);
4069 }
4070 EXPORT_SYMBOL(sk_common_release);
4071 
4072 void sk_get_meminfo(const struct sock *sk, u32 *mem)
4073 {
4074 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
4075 
4076 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
4077 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
4078 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
4079 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
4080 	mem[SK_MEMINFO_FWD_ALLOC] = READ_ONCE(sk->sk_forward_alloc);
4081 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
4082 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
4083 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
4084 	mem[SK_MEMINFO_DROPS] = sk_drops_read(sk);
4085 }
4086 
4087 #ifdef CONFIG_PROC_FS
4088 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
4089 
4090 int sock_prot_inuse_get(struct net *net, struct proto *prot)
4091 {
4092 	int cpu, idx = prot->inuse_idx;
4093 	int res = 0;
4094 
4095 	for_each_possible_cpu(cpu)
4096 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
4097 
4098 	return res >= 0 ? res : 0;
4099 }
4100 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
4101 
4102 int sock_inuse_get(struct net *net)
4103 {
4104 	int cpu, res = 0;
4105 
4106 	for_each_possible_cpu(cpu)
4107 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
4108 
4109 	return res;
4110 }
4111 
4112 EXPORT_SYMBOL_GPL(sock_inuse_get);
4113 
4114 static int __net_init sock_inuse_init_net(struct net *net)
4115 {
4116 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
4117 	if (net->core.prot_inuse == NULL)
4118 		return -ENOMEM;
4119 	return 0;
4120 }
4121 
4122 static void __net_exit sock_inuse_exit_net(struct net *net)
4123 {
4124 	free_percpu(net->core.prot_inuse);
4125 }
4126 
4127 static struct pernet_operations net_inuse_ops = {
4128 	.init = sock_inuse_init_net,
4129 	.exit = sock_inuse_exit_net,
4130 };
4131 
4132 static __init int net_inuse_init(void)
4133 {
4134 	if (register_pernet_subsys(&net_inuse_ops))
4135 		panic("Cannot initialize net inuse counters");
4136 
4137 	return 0;
4138 }
4139 
4140 core_initcall(net_inuse_init);
4141 
4142 static int assign_proto_idx(struct proto *prot)
4143 {
4144 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
4145 
4146 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR)) {
4147 		pr_err("PROTO_INUSE_NR exhausted\n");
4148 		return -ENOSPC;
4149 	}
4150 
4151 	set_bit(prot->inuse_idx, proto_inuse_idx);
4152 	return 0;
4153 }
4154 
4155 static void release_proto_idx(struct proto *prot)
4156 {
4157 	if (prot->inuse_idx != PROTO_INUSE_NR)
4158 		clear_bit(prot->inuse_idx, proto_inuse_idx);
4159 }
4160 #else
4161 static inline int assign_proto_idx(struct proto *prot)
4162 {
4163 	return 0;
4164 }
4165 
4166 static inline void release_proto_idx(struct proto *prot)
4167 {
4168 }
4169 
4170 #endif
4171 
4172 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
4173 {
4174 	if (!twsk_prot)
4175 		return;
4176 	kfree(twsk_prot->twsk_slab_name);
4177 	twsk_prot->twsk_slab_name = NULL;
4178 	kmem_cache_destroy(twsk_prot->twsk_slab);
4179 	twsk_prot->twsk_slab = NULL;
4180 }
4181 
4182 static int tw_prot_init(const struct proto *prot)
4183 {
4184 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
4185 
4186 	if (!twsk_prot)
4187 		return 0;
4188 
4189 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
4190 					      prot->name);
4191 	if (!twsk_prot->twsk_slab_name)
4192 		return -ENOMEM;
4193 
4194 	twsk_prot->twsk_slab =
4195 		kmem_cache_create(twsk_prot->twsk_slab_name,
4196 				  twsk_prot->twsk_obj_size, 0,
4197 				  SLAB_ACCOUNT | prot->slab_flags,
4198 				  NULL);
4199 	if (!twsk_prot->twsk_slab) {
4200 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
4201 			prot->name);
4202 		return -ENOMEM;
4203 	}
4204 
4205 	return 0;
4206 }
4207 
4208 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
4209 {
4210 	if (!rsk_prot)
4211 		return;
4212 	kfree(rsk_prot->slab_name);
4213 	rsk_prot->slab_name = NULL;
4214 	kmem_cache_destroy(rsk_prot->slab);
4215 	rsk_prot->slab = NULL;
4216 }
4217 
4218 static int req_prot_init(const struct proto *prot)
4219 {
4220 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
4221 
4222 	if (!rsk_prot)
4223 		return 0;
4224 
4225 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
4226 					prot->name);
4227 	if (!rsk_prot->slab_name)
4228 		return -ENOMEM;
4229 
4230 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
4231 					   rsk_prot->obj_size, 0,
4232 					   SLAB_ACCOUNT | prot->slab_flags,
4233 					   NULL);
4234 
4235 	if (!rsk_prot->slab) {
4236 		pr_crit("%s: Can't create request sock SLAB cache!\n",
4237 			prot->name);
4238 		return -ENOMEM;
4239 	}
4240 	return 0;
4241 }
4242 
4243 int proto_register(struct proto *prot, int alloc_slab)
4244 {
4245 	int ret = -ENOBUFS;
4246 
4247 	if (prot->memory_allocated && !prot->sysctl_mem) {
4248 		pr_err("%s: missing sysctl_mem\n", prot->name);
4249 		return -EINVAL;
4250 	}
4251 	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
4252 		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
4253 		return -EINVAL;
4254 	}
4255 	if (alloc_slab) {
4256 		struct kmem_cache_args args = {
4257 			.useroffset	= prot->useroffset,
4258 			.usersize	= prot->usersize,
4259 			.freeptr_offset = prot->freeptr_offset,
4260 			.use_freeptr_offset = !!prot->freeptr_offset,
4261 		};
4262 
4263 		prot->slab = kmem_cache_create(prot->name, prot->obj_size,
4264 					&args,
4265 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
4266 					prot->slab_flags);
4267 		if (prot->slab == NULL) {
4268 			pr_crit("%s: Can't create sock SLAB cache!\n",
4269 				prot->name);
4270 			goto out;
4271 		}
4272 
4273 		if (req_prot_init(prot))
4274 			goto out_free_request_sock_slab;
4275 
4276 		if (tw_prot_init(prot))
4277 			goto out_free_timewait_sock_slab;
4278 	}
4279 
4280 	mutex_lock(&proto_list_mutex);
4281 	ret = assign_proto_idx(prot);
4282 	if (ret) {
4283 		mutex_unlock(&proto_list_mutex);
4284 		goto out_free_timewait_sock_slab;
4285 	}
4286 	list_add(&prot->node, &proto_list);
4287 	mutex_unlock(&proto_list_mutex);
4288 	return ret;
4289 
4290 out_free_timewait_sock_slab:
4291 	if (alloc_slab)
4292 		tw_prot_cleanup(prot->twsk_prot);
4293 out_free_request_sock_slab:
4294 	if (alloc_slab) {
4295 		req_prot_cleanup(prot->rsk_prot);
4296 
4297 		kmem_cache_destroy(prot->slab);
4298 		prot->slab = NULL;
4299 	}
4300 out:
4301 	return ret;
4302 }
4303 EXPORT_SYMBOL(proto_register);
4304 
4305 void proto_unregister(struct proto *prot)
4306 {
4307 	mutex_lock(&proto_list_mutex);
4308 	release_proto_idx(prot);
4309 	list_del(&prot->node);
4310 	mutex_unlock(&proto_list_mutex);
4311 
4312 	kmem_cache_destroy(prot->slab);
4313 	prot->slab = NULL;
4314 
4315 	req_prot_cleanup(prot->rsk_prot);
4316 	tw_prot_cleanup(prot->twsk_prot);
4317 }
4318 EXPORT_SYMBOL(proto_unregister);
4319 
4320 int sock_load_diag_module(int family, int protocol)
4321 {
4322 	if (!protocol) {
4323 		if (!sock_is_registered(family))
4324 			return -ENOENT;
4325 
4326 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4327 				      NETLINK_SOCK_DIAG, family);
4328 	}
4329 
4330 #ifdef CONFIG_INET
4331 	if (family == AF_INET &&
4332 	    protocol != IPPROTO_RAW &&
4333 	    protocol < MAX_INET_PROTOS &&
4334 	    !rcu_access_pointer(inet_protos[protocol]))
4335 		return -ENOENT;
4336 #endif
4337 
4338 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4339 			      NETLINK_SOCK_DIAG, family, protocol);
4340 }
4341 EXPORT_SYMBOL(sock_load_diag_module);
4342 
4343 #ifdef CONFIG_PROC_FS
4344 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4345 	__acquires(proto_list_mutex)
4346 {
4347 	mutex_lock(&proto_list_mutex);
4348 	return seq_list_start_head(&proto_list, *pos);
4349 }
4350 
4351 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4352 {
4353 	return seq_list_next(v, &proto_list, pos);
4354 }
4355 
4356 static void proto_seq_stop(struct seq_file *seq, void *v)
4357 	__releases(proto_list_mutex)
4358 {
4359 	mutex_unlock(&proto_list_mutex);
4360 }
4361 
4362 static char proto_method_implemented(const void *method)
4363 {
4364 	return method == NULL ? 'n' : 'y';
4365 }
4366 static long sock_prot_memory_allocated(struct proto *proto)
4367 {
4368 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4369 }
4370 
4371 static const char *sock_prot_memory_pressure(struct proto *proto)
4372 {
4373 	return proto->memory_pressure != NULL ?
4374 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4375 }
4376 
4377 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4378 {
4379 
4380 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4381 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4382 		   proto->name,
4383 		   proto->obj_size,
4384 		   sock_prot_inuse_get(seq_file_net(seq), proto),
4385 		   sock_prot_memory_allocated(proto),
4386 		   sock_prot_memory_pressure(proto),
4387 		   proto->max_header,
4388 		   proto->slab == NULL ? "no" : "yes",
4389 		   module_name(proto->owner),
4390 		   proto_method_implemented(proto->close),
4391 		   proto_method_implemented(proto->connect),
4392 		   proto_method_implemented(proto->disconnect),
4393 		   proto_method_implemented(proto->accept),
4394 		   proto_method_implemented(proto->ioctl),
4395 		   proto_method_implemented(proto->init),
4396 		   proto_method_implemented(proto->destroy),
4397 		   proto_method_implemented(proto->shutdown),
4398 		   proto_method_implemented(proto->setsockopt),
4399 		   proto_method_implemented(proto->getsockopt),
4400 		   proto_method_implemented(proto->sendmsg),
4401 		   proto_method_implemented(proto->recvmsg),
4402 		   proto_method_implemented(proto->bind),
4403 		   proto_method_implemented(proto->backlog_rcv),
4404 		   proto_method_implemented(proto->hash),
4405 		   proto_method_implemented(proto->unhash),
4406 		   proto_method_implemented(proto->get_port),
4407 		   proto_method_implemented(proto->enter_memory_pressure));
4408 }
4409 
4410 static int proto_seq_show(struct seq_file *seq, void *v)
4411 {
4412 	if (v == &proto_list)
4413 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4414 			   "protocol",
4415 			   "size",
4416 			   "sockets",
4417 			   "memory",
4418 			   "press",
4419 			   "maxhdr",
4420 			   "slab",
4421 			   "module",
4422 			   "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4423 	else
4424 		proto_seq_printf(seq, list_entry(v, struct proto, node));
4425 	return 0;
4426 }
4427 
4428 static const struct seq_operations proto_seq_ops = {
4429 	.start  = proto_seq_start,
4430 	.next   = proto_seq_next,
4431 	.stop   = proto_seq_stop,
4432 	.show   = proto_seq_show,
4433 };
4434 
4435 static __net_init int proto_init_net(struct net *net)
4436 {
4437 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4438 			sizeof(struct seq_net_private)))
4439 		return -ENOMEM;
4440 
4441 	return 0;
4442 }
4443 
4444 static __net_exit void proto_exit_net(struct net *net)
4445 {
4446 	remove_proc_entry("protocols", net->proc_net);
4447 }
4448 
4449 
4450 static __net_initdata struct pernet_operations proto_net_ops = {
4451 	.init = proto_init_net,
4452 	.exit = proto_exit_net,
4453 };
4454 
4455 static int __init proto_init(void)
4456 {
4457 	return register_pernet_subsys(&proto_net_ops);
4458 }
4459 
4460 subsys_initcall(proto_init);
4461 
4462 #endif /* PROC_FS */
4463 
4464 #ifdef CONFIG_NET_RX_BUSY_POLL
4465 bool sk_busy_loop_end(void *p, unsigned long start_time)
4466 {
4467 	struct sock *sk = p;
4468 
4469 	if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4470 		return true;
4471 
4472 	if (sk_is_udp(sk) &&
4473 	    !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4474 		return true;
4475 
4476 	return sk_busy_loop_timeout(sk, start_time);
4477 }
4478 EXPORT_SYMBOL(sk_busy_loop_end);
4479 #endif /* CONFIG_NET_RX_BUSY_POLL */
4480 
4481 int sock_bind_add(struct sock *sk, struct sockaddr_unsized *addr, int addr_len)
4482 {
4483 	if (!sk->sk_prot->bind_add)
4484 		return -EOPNOTSUPP;
4485 	return sk->sk_prot->bind_add(sk, addr, addr_len);
4486 }
4487 EXPORT_SYMBOL(sock_bind_add);
4488 
4489 /* Copy 'size' bytes from userspace and return `size` back to userspace */
4490 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4491 		     void __user *arg, void *karg, size_t size)
4492 {
4493 	int ret;
4494 
4495 	if (copy_from_user(karg, arg, size))
4496 		return -EFAULT;
4497 
4498 	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4499 	if (ret)
4500 		return ret;
4501 
4502 	if (copy_to_user(arg, karg, size))
4503 		return -EFAULT;
4504 
4505 	return 0;
4506 }
4507 EXPORT_SYMBOL(sock_ioctl_inout);
4508 
4509 /* This is the most common ioctl prep function, where the result (4 bytes) is
4510  * copied back to userspace if the ioctl() returns successfully. No input is
4511  * copied from userspace as input argument.
4512  */
4513 static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4514 {
4515 	int ret, karg = 0;
4516 
4517 	ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4518 	if (ret)
4519 		return ret;
4520 
4521 	return put_user(karg, (int __user *)arg);
4522 }
4523 
4524 /* A wrapper around sock ioctls, which copies the data from userspace
4525  * (depending on the protocol/ioctl), and copies back the result to userspace.
4526  * The main motivation for this function is to pass kernel memory to the
4527  * protocol ioctl callbacks, instead of userspace memory.
4528  */
4529 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4530 {
4531 	int rc = 1;
4532 
4533 	if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4534 		rc = ipmr_sk_ioctl(sk, cmd, arg);
4535 	else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4536 		rc = ip6mr_sk_ioctl(sk, cmd, arg);
4537 	else if (sk_is_phonet(sk))
4538 		rc = phonet_sk_ioctl(sk, cmd, arg);
4539 
4540 	/* If ioctl was processed, returns its value */
4541 	if (rc <= 0)
4542 		return rc;
4543 
4544 	/* Otherwise call the default handler */
4545 	return sock_ioctl_out(sk, cmd, arg);
4546 }
4547 EXPORT_SYMBOL(sk_ioctl);
4548 
4549 static int __init sock_struct_check(void)
4550 {
4551 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_drops);
4552 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_peek_off);
4553 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_error_queue);
4554 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_receive_queue);
4555 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_backlog);
4556 
4557 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst);
4558 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_ifindex);
4559 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_cookie);
4560 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvbuf);
4561 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_filter);
4562 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_wq);
4563 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_data_ready);
4564 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvtimeo);
4565 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvlowat);
4566 
4567 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_err);
4568 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_socket);
4569 #ifdef CONFIG_MEMCG
4570 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_memcg);
4571 #endif
4572 
4573 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_lock);
4574 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_reserved_mem);
4575 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_forward_alloc);
4576 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_tsflags);
4577 
4578 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4579 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4580 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_err_soft);
4581 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_queued);
4582 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_alloc);
4583 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tsq_flags);
4584 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_send_head);
4585 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_queue);
4586 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_pending);
4587 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_frag);
4588 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_timer);
4589 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_rate);
4590 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_zckey);
4591 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tskey);
4592 
4593 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_pending_confirm);
4594 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_status);
4595 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_max_pacing_rate);
4596 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndtimeo);
4597 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_priority);
4598 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_mark);
4599 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_uid);
4600 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_protocol);
4601 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_cache);
4602 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_route_caps);
4603 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_type);
4604 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_size);
4605 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_allocation);
4606 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_txhash);
4607 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndbuf);
4608 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_segs);
4609 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_shift);
4610 	CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_use_task_frag);
4611 	return 0;
4612 }
4613 
4614 core_initcall(sock_struct_check);
4615