xref: /linux/net/core/sock.c (revision c546656f31c5138afcaddfcd8f8b93fbf73e4d3a)
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 <asm/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/init.h>
111 #include <linux/highmem.h>
112 #include <linux/user_namespace.h>
113 #include <linux/static_key.h>
114 #include <linux/memcontrol.h>
115 #include <linux/prefetch.h>
116 #include <linux/compat.h>
117 
118 #include <linux/uaccess.h>
119 
120 #include <linux/netdevice.h>
121 #include <net/protocol.h>
122 #include <linux/skbuff.h>
123 #include <net/net_namespace.h>
124 #include <net/request_sock.h>
125 #include <net/sock.h>
126 #include <linux/net_tstamp.h>
127 #include <net/xfrm.h>
128 #include <linux/ipsec.h>
129 #include <net/cls_cgroup.h>
130 #include <net/netprio_cgroup.h>
131 #include <linux/sock_diag.h>
132 
133 #include <linux/filter.h>
134 #include <net/sock_reuseport.h>
135 #include <net/bpf_sk_storage.h>
136 
137 #include <trace/events/sock.h>
138 
139 #include <net/tcp.h>
140 #include <net/busy_poll.h>
141 
142 #include <linux/ethtool.h>
143 
144 #include "dev.h"
145 
146 static DEFINE_MUTEX(proto_list_mutex);
147 static LIST_HEAD(proto_list);
148 
149 static void sock_def_write_space_wfree(struct sock *sk);
150 static void sock_def_write_space(struct sock *sk);
151 
152 /**
153  * sk_ns_capable - General socket capability test
154  * @sk: Socket to use a capability on or through
155  * @user_ns: The user namespace of the capability to use
156  * @cap: The capability to use
157  *
158  * Test to see if the opener of the socket had when the socket was
159  * created and the current process has the capability @cap in the user
160  * namespace @user_ns.
161  */
162 bool sk_ns_capable(const struct sock *sk,
163 		   struct user_namespace *user_ns, int cap)
164 {
165 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
166 		ns_capable(user_ns, cap);
167 }
168 EXPORT_SYMBOL(sk_ns_capable);
169 
170 /**
171  * sk_capable - Socket global capability test
172  * @sk: Socket to use a capability on or through
173  * @cap: The global capability to use
174  *
175  * Test to see if the opener of the socket had when the socket was
176  * created and the current process has the capability @cap in all user
177  * namespaces.
178  */
179 bool sk_capable(const struct sock *sk, int cap)
180 {
181 	return sk_ns_capable(sk, &init_user_ns, cap);
182 }
183 EXPORT_SYMBOL(sk_capable);
184 
185 /**
186  * sk_net_capable - Network namespace socket capability test
187  * @sk: Socket to use a capability on or through
188  * @cap: The capability to use
189  *
190  * Test to see if the opener of the socket had when the socket was created
191  * and the current process has the capability @cap over the network namespace
192  * the socket is a member of.
193  */
194 bool sk_net_capable(const struct sock *sk, int cap)
195 {
196 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
197 }
198 EXPORT_SYMBOL(sk_net_capable);
199 
200 /*
201  * Each address family might have different locking rules, so we have
202  * one slock key per address family and separate keys for internal and
203  * userspace sockets.
204  */
205 static struct lock_class_key af_family_keys[AF_MAX];
206 static struct lock_class_key af_family_kern_keys[AF_MAX];
207 static struct lock_class_key af_family_slock_keys[AF_MAX];
208 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
209 
210 /*
211  * Make lock validator output more readable. (we pre-construct these
212  * strings build-time, so that runtime initialization of socket
213  * locks is fast):
214  */
215 
216 #define _sock_locks(x)						  \
217   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
218   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
219   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
220   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
221   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
222   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
223   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
224   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
225   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
226   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
227   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
228   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
229   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
230   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
231   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
232   x "AF_MCTP"  , \
233   x "AF_MAX"
234 
235 static const char *const af_family_key_strings[AF_MAX+1] = {
236 	_sock_locks("sk_lock-")
237 };
238 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
239 	_sock_locks("slock-")
240 };
241 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
242 	_sock_locks("clock-")
243 };
244 
245 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
246 	_sock_locks("k-sk_lock-")
247 };
248 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
249 	_sock_locks("k-slock-")
250 };
251 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
252 	_sock_locks("k-clock-")
253 };
254 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
255 	_sock_locks("rlock-")
256 };
257 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
258 	_sock_locks("wlock-")
259 };
260 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
261 	_sock_locks("elock-")
262 };
263 
264 /*
265  * sk_callback_lock and sk queues locking rules are per-address-family,
266  * so split the lock classes by using a per-AF key:
267  */
268 static struct lock_class_key af_callback_keys[AF_MAX];
269 static struct lock_class_key af_rlock_keys[AF_MAX];
270 static struct lock_class_key af_wlock_keys[AF_MAX];
271 static struct lock_class_key af_elock_keys[AF_MAX];
272 static struct lock_class_key af_kern_callback_keys[AF_MAX];
273 
274 /* Run time adjustable parameters. */
275 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
276 EXPORT_SYMBOL(sysctl_wmem_max);
277 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
278 EXPORT_SYMBOL(sysctl_rmem_max);
279 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
280 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
281 
282 /* Maximal space eaten by iovec or ancillary data plus some space */
283 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
284 EXPORT_SYMBOL(sysctl_optmem_max);
285 
286 int sysctl_tstamp_allow_data __read_mostly = 1;
287 
288 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
289 EXPORT_SYMBOL_GPL(memalloc_socks_key);
290 
291 /**
292  * sk_set_memalloc - sets %SOCK_MEMALLOC
293  * @sk: socket to set it on
294  *
295  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
296  * It's the responsibility of the admin to adjust min_free_kbytes
297  * to meet the requirements
298  */
299 void sk_set_memalloc(struct sock *sk)
300 {
301 	sock_set_flag(sk, SOCK_MEMALLOC);
302 	sk->sk_allocation |= __GFP_MEMALLOC;
303 	static_branch_inc(&memalloc_socks_key);
304 }
305 EXPORT_SYMBOL_GPL(sk_set_memalloc);
306 
307 void sk_clear_memalloc(struct sock *sk)
308 {
309 	sock_reset_flag(sk, SOCK_MEMALLOC);
310 	sk->sk_allocation &= ~__GFP_MEMALLOC;
311 	static_branch_dec(&memalloc_socks_key);
312 
313 	/*
314 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
315 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
316 	 * it has rmem allocations due to the last swapfile being deactivated
317 	 * but there is a risk that the socket is unusable due to exceeding
318 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
319 	 */
320 	sk_mem_reclaim(sk);
321 }
322 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
323 
324 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
325 {
326 	int ret;
327 	unsigned int noreclaim_flag;
328 
329 	/* these should have been dropped before queueing */
330 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
331 
332 	noreclaim_flag = memalloc_noreclaim_save();
333 	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
334 				 tcp_v6_do_rcv,
335 				 tcp_v4_do_rcv,
336 				 sk, skb);
337 	memalloc_noreclaim_restore(noreclaim_flag);
338 
339 	return ret;
340 }
341 EXPORT_SYMBOL(__sk_backlog_rcv);
342 
343 void sk_error_report(struct sock *sk)
344 {
345 	sk->sk_error_report(sk);
346 
347 	switch (sk->sk_family) {
348 	case AF_INET:
349 		fallthrough;
350 	case AF_INET6:
351 		trace_inet_sk_error_report(sk);
352 		break;
353 	default:
354 		break;
355 	}
356 }
357 EXPORT_SYMBOL(sk_error_report);
358 
359 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
360 {
361 	struct __kernel_sock_timeval tv;
362 
363 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
364 		tv.tv_sec = 0;
365 		tv.tv_usec = 0;
366 	} else {
367 		tv.tv_sec = timeo / HZ;
368 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
369 	}
370 
371 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
372 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
373 		*(struct old_timeval32 *)optval = tv32;
374 		return sizeof(tv32);
375 	}
376 
377 	if (old_timeval) {
378 		struct __kernel_old_timeval old_tv;
379 		old_tv.tv_sec = tv.tv_sec;
380 		old_tv.tv_usec = tv.tv_usec;
381 		*(struct __kernel_old_timeval *)optval = old_tv;
382 		return sizeof(old_tv);
383 	}
384 
385 	*(struct __kernel_sock_timeval *)optval = tv;
386 	return sizeof(tv);
387 }
388 EXPORT_SYMBOL(sock_get_timeout);
389 
390 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
391 			   sockptr_t optval, int optlen, bool old_timeval)
392 {
393 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
394 		struct old_timeval32 tv32;
395 
396 		if (optlen < sizeof(tv32))
397 			return -EINVAL;
398 
399 		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
400 			return -EFAULT;
401 		tv->tv_sec = tv32.tv_sec;
402 		tv->tv_usec = tv32.tv_usec;
403 	} else if (old_timeval) {
404 		struct __kernel_old_timeval old_tv;
405 
406 		if (optlen < sizeof(old_tv))
407 			return -EINVAL;
408 		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
409 			return -EFAULT;
410 		tv->tv_sec = old_tv.tv_sec;
411 		tv->tv_usec = old_tv.tv_usec;
412 	} else {
413 		if (optlen < sizeof(*tv))
414 			return -EINVAL;
415 		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
416 			return -EFAULT;
417 	}
418 
419 	return 0;
420 }
421 EXPORT_SYMBOL(sock_copy_user_timeval);
422 
423 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
424 			    bool old_timeval)
425 {
426 	struct __kernel_sock_timeval tv;
427 	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
428 
429 	if (err)
430 		return err;
431 
432 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
433 		return -EDOM;
434 
435 	if (tv.tv_sec < 0) {
436 		static int warned __read_mostly;
437 
438 		*timeo_p = 0;
439 		if (warned < 10 && net_ratelimit()) {
440 			warned++;
441 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
442 				__func__, current->comm, task_pid_nr(current));
443 		}
444 		return 0;
445 	}
446 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
447 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
448 		return 0;
449 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
450 		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
451 	return 0;
452 }
453 
454 static bool sock_needs_netstamp(const struct sock *sk)
455 {
456 	switch (sk->sk_family) {
457 	case AF_UNSPEC:
458 	case AF_UNIX:
459 		return false;
460 	default:
461 		return true;
462 	}
463 }
464 
465 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
466 {
467 	if (sk->sk_flags & flags) {
468 		sk->sk_flags &= ~flags;
469 		if (sock_needs_netstamp(sk) &&
470 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
471 			net_disable_timestamp();
472 	}
473 }
474 
475 
476 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
477 {
478 	unsigned long flags;
479 	struct sk_buff_head *list = &sk->sk_receive_queue;
480 
481 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
482 		atomic_inc(&sk->sk_drops);
483 		trace_sock_rcvqueue_full(sk, skb);
484 		return -ENOMEM;
485 	}
486 
487 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
488 		atomic_inc(&sk->sk_drops);
489 		return -ENOBUFS;
490 	}
491 
492 	skb->dev = NULL;
493 	skb_set_owner_r(skb, sk);
494 
495 	/* we escape from rcu protected region, make sure we dont leak
496 	 * a norefcounted dst
497 	 */
498 	skb_dst_force(skb);
499 
500 	spin_lock_irqsave(&list->lock, flags);
501 	sock_skb_set_dropcount(sk, skb);
502 	__skb_queue_tail(list, skb);
503 	spin_unlock_irqrestore(&list->lock, flags);
504 
505 	if (!sock_flag(sk, SOCK_DEAD))
506 		sk->sk_data_ready(sk);
507 	return 0;
508 }
509 EXPORT_SYMBOL(__sock_queue_rcv_skb);
510 
511 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
512 			      enum skb_drop_reason *reason)
513 {
514 	enum skb_drop_reason drop_reason;
515 	int err;
516 
517 	err = sk_filter(sk, skb);
518 	if (err) {
519 		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
520 		goto out;
521 	}
522 	err = __sock_queue_rcv_skb(sk, skb);
523 	switch (err) {
524 	case -ENOMEM:
525 		drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
526 		break;
527 	case -ENOBUFS:
528 		drop_reason = SKB_DROP_REASON_PROTO_MEM;
529 		break;
530 	default:
531 		drop_reason = SKB_NOT_DROPPED_YET;
532 		break;
533 	}
534 out:
535 	if (reason)
536 		*reason = drop_reason;
537 	return err;
538 }
539 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
540 
541 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
542 		     const int nested, unsigned int trim_cap, bool refcounted)
543 {
544 	int rc = NET_RX_SUCCESS;
545 
546 	if (sk_filter_trim_cap(sk, skb, trim_cap))
547 		goto discard_and_relse;
548 
549 	skb->dev = NULL;
550 
551 	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
552 		atomic_inc(&sk->sk_drops);
553 		goto discard_and_relse;
554 	}
555 	if (nested)
556 		bh_lock_sock_nested(sk);
557 	else
558 		bh_lock_sock(sk);
559 	if (!sock_owned_by_user(sk)) {
560 		/*
561 		 * trylock + unlock semantics:
562 		 */
563 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
564 
565 		rc = sk_backlog_rcv(sk, skb);
566 
567 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
568 	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
569 		bh_unlock_sock(sk);
570 		atomic_inc(&sk->sk_drops);
571 		goto discard_and_relse;
572 	}
573 
574 	bh_unlock_sock(sk);
575 out:
576 	if (refcounted)
577 		sock_put(sk);
578 	return rc;
579 discard_and_relse:
580 	kfree_skb(skb);
581 	goto out;
582 }
583 EXPORT_SYMBOL(__sk_receive_skb);
584 
585 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
586 							  u32));
587 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
588 							   u32));
589 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
590 {
591 	struct dst_entry *dst = __sk_dst_get(sk);
592 
593 	if (dst && dst->obsolete &&
594 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
595 			       dst, cookie) == NULL) {
596 		sk_tx_queue_clear(sk);
597 		sk->sk_dst_pending_confirm = 0;
598 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
599 		dst_release(dst);
600 		return NULL;
601 	}
602 
603 	return dst;
604 }
605 EXPORT_SYMBOL(__sk_dst_check);
606 
607 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
608 {
609 	struct dst_entry *dst = sk_dst_get(sk);
610 
611 	if (dst && dst->obsolete &&
612 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
613 			       dst, cookie) == NULL) {
614 		sk_dst_reset(sk);
615 		dst_release(dst);
616 		return NULL;
617 	}
618 
619 	return dst;
620 }
621 EXPORT_SYMBOL(sk_dst_check);
622 
623 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
624 {
625 	int ret = -ENOPROTOOPT;
626 #ifdef CONFIG_NETDEVICES
627 	struct net *net = sock_net(sk);
628 
629 	/* Sorry... */
630 	ret = -EPERM;
631 	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
632 		goto out;
633 
634 	ret = -EINVAL;
635 	if (ifindex < 0)
636 		goto out;
637 
638 	/* Paired with all READ_ONCE() done locklessly. */
639 	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
640 
641 	if (sk->sk_prot->rehash)
642 		sk->sk_prot->rehash(sk);
643 	sk_dst_reset(sk);
644 
645 	ret = 0;
646 
647 out:
648 #endif
649 
650 	return ret;
651 }
652 
653 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
654 {
655 	int ret;
656 
657 	if (lock_sk)
658 		lock_sock(sk);
659 	ret = sock_bindtoindex_locked(sk, ifindex);
660 	if (lock_sk)
661 		release_sock(sk);
662 
663 	return ret;
664 }
665 EXPORT_SYMBOL(sock_bindtoindex);
666 
667 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
668 {
669 	int ret = -ENOPROTOOPT;
670 #ifdef CONFIG_NETDEVICES
671 	struct net *net = sock_net(sk);
672 	char devname[IFNAMSIZ];
673 	int index;
674 
675 	ret = -EINVAL;
676 	if (optlen < 0)
677 		goto out;
678 
679 	/* Bind this socket to a particular device like "eth0",
680 	 * as specified in the passed interface name. If the
681 	 * name is "" or the option length is zero the socket
682 	 * is not bound.
683 	 */
684 	if (optlen > IFNAMSIZ - 1)
685 		optlen = IFNAMSIZ - 1;
686 	memset(devname, 0, sizeof(devname));
687 
688 	ret = -EFAULT;
689 	if (copy_from_sockptr(devname, optval, optlen))
690 		goto out;
691 
692 	index = 0;
693 	if (devname[0] != '\0') {
694 		struct net_device *dev;
695 
696 		rcu_read_lock();
697 		dev = dev_get_by_name_rcu(net, devname);
698 		if (dev)
699 			index = dev->ifindex;
700 		rcu_read_unlock();
701 		ret = -ENODEV;
702 		if (!dev)
703 			goto out;
704 	}
705 
706 	sockopt_lock_sock(sk);
707 	ret = sock_bindtoindex_locked(sk, index);
708 	sockopt_release_sock(sk);
709 out:
710 #endif
711 
712 	return ret;
713 }
714 
715 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
716 				sockptr_t optlen, int len)
717 {
718 	int ret = -ENOPROTOOPT;
719 #ifdef CONFIG_NETDEVICES
720 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
721 	struct net *net = sock_net(sk);
722 	char devname[IFNAMSIZ];
723 
724 	if (bound_dev_if == 0) {
725 		len = 0;
726 		goto zero;
727 	}
728 
729 	ret = -EINVAL;
730 	if (len < IFNAMSIZ)
731 		goto out;
732 
733 	ret = netdev_get_name(net, devname, bound_dev_if);
734 	if (ret)
735 		goto out;
736 
737 	len = strlen(devname) + 1;
738 
739 	ret = -EFAULT;
740 	if (copy_to_sockptr(optval, devname, len))
741 		goto out;
742 
743 zero:
744 	ret = -EFAULT;
745 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
746 		goto out;
747 
748 	ret = 0;
749 
750 out:
751 #endif
752 
753 	return ret;
754 }
755 
756 bool sk_mc_loop(struct sock *sk)
757 {
758 	if (dev_recursion_level())
759 		return false;
760 	if (!sk)
761 		return true;
762 	switch (sk->sk_family) {
763 	case AF_INET:
764 		return inet_sk(sk)->mc_loop;
765 #if IS_ENABLED(CONFIG_IPV6)
766 	case AF_INET6:
767 		return inet6_sk(sk)->mc_loop;
768 #endif
769 	}
770 	WARN_ON_ONCE(1);
771 	return true;
772 }
773 EXPORT_SYMBOL(sk_mc_loop);
774 
775 void sock_set_reuseaddr(struct sock *sk)
776 {
777 	lock_sock(sk);
778 	sk->sk_reuse = SK_CAN_REUSE;
779 	release_sock(sk);
780 }
781 EXPORT_SYMBOL(sock_set_reuseaddr);
782 
783 void sock_set_reuseport(struct sock *sk)
784 {
785 	lock_sock(sk);
786 	sk->sk_reuseport = true;
787 	release_sock(sk);
788 }
789 EXPORT_SYMBOL(sock_set_reuseport);
790 
791 void sock_no_linger(struct sock *sk)
792 {
793 	lock_sock(sk);
794 	sk->sk_lingertime = 0;
795 	sock_set_flag(sk, SOCK_LINGER);
796 	release_sock(sk);
797 }
798 EXPORT_SYMBOL(sock_no_linger);
799 
800 void sock_set_priority(struct sock *sk, u32 priority)
801 {
802 	lock_sock(sk);
803 	sk->sk_priority = priority;
804 	release_sock(sk);
805 }
806 EXPORT_SYMBOL(sock_set_priority);
807 
808 void sock_set_sndtimeo(struct sock *sk, s64 secs)
809 {
810 	lock_sock(sk);
811 	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
812 		sk->sk_sndtimeo = secs * HZ;
813 	else
814 		sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
815 	release_sock(sk);
816 }
817 EXPORT_SYMBOL(sock_set_sndtimeo);
818 
819 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
820 {
821 	if (val)  {
822 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
823 		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
824 		sock_set_flag(sk, SOCK_RCVTSTAMP);
825 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
826 	} else {
827 		sock_reset_flag(sk, SOCK_RCVTSTAMP);
828 		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
829 	}
830 }
831 
832 void sock_enable_timestamps(struct sock *sk)
833 {
834 	lock_sock(sk);
835 	__sock_set_timestamps(sk, true, false, true);
836 	release_sock(sk);
837 }
838 EXPORT_SYMBOL(sock_enable_timestamps);
839 
840 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
841 {
842 	switch (optname) {
843 	case SO_TIMESTAMP_OLD:
844 		__sock_set_timestamps(sk, valbool, false, false);
845 		break;
846 	case SO_TIMESTAMP_NEW:
847 		__sock_set_timestamps(sk, valbool, true, false);
848 		break;
849 	case SO_TIMESTAMPNS_OLD:
850 		__sock_set_timestamps(sk, valbool, false, true);
851 		break;
852 	case SO_TIMESTAMPNS_NEW:
853 		__sock_set_timestamps(sk, valbool, true, true);
854 		break;
855 	}
856 }
857 
858 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
859 {
860 	struct net *net = sock_net(sk);
861 	struct net_device *dev = NULL;
862 	bool match = false;
863 	int *vclock_index;
864 	int i, num;
865 
866 	if (sk->sk_bound_dev_if)
867 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
868 
869 	if (!dev) {
870 		pr_err("%s: sock not bind to device\n", __func__);
871 		return -EOPNOTSUPP;
872 	}
873 
874 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
875 	dev_put(dev);
876 
877 	for (i = 0; i < num; i++) {
878 		if (*(vclock_index + i) == phc_index) {
879 			match = true;
880 			break;
881 		}
882 	}
883 
884 	if (num > 0)
885 		kfree(vclock_index);
886 
887 	if (!match)
888 		return -EINVAL;
889 
890 	sk->sk_bind_phc = phc_index;
891 
892 	return 0;
893 }
894 
895 int sock_set_timestamping(struct sock *sk, int optname,
896 			  struct so_timestamping timestamping)
897 {
898 	int val = timestamping.flags;
899 	int ret;
900 
901 	if (val & ~SOF_TIMESTAMPING_MASK)
902 		return -EINVAL;
903 
904 	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
905 	    !(val & SOF_TIMESTAMPING_OPT_ID))
906 		return -EINVAL;
907 
908 	if (val & SOF_TIMESTAMPING_OPT_ID &&
909 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
910 		if (sk_is_tcp(sk)) {
911 			if ((1 << sk->sk_state) &
912 			    (TCPF_CLOSE | TCPF_LISTEN))
913 				return -EINVAL;
914 			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
915 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
916 			else
917 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
918 		} else {
919 			atomic_set(&sk->sk_tskey, 0);
920 		}
921 	}
922 
923 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
924 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
925 		return -EINVAL;
926 
927 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
928 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
929 		if (ret)
930 			return ret;
931 	}
932 
933 	sk->sk_tsflags = val;
934 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
935 
936 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
937 		sock_enable_timestamp(sk,
938 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
939 	else
940 		sock_disable_timestamp(sk,
941 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
942 	return 0;
943 }
944 
945 void sock_set_keepalive(struct sock *sk)
946 {
947 	lock_sock(sk);
948 	if (sk->sk_prot->keepalive)
949 		sk->sk_prot->keepalive(sk, true);
950 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
951 	release_sock(sk);
952 }
953 EXPORT_SYMBOL(sock_set_keepalive);
954 
955 static void __sock_set_rcvbuf(struct sock *sk, int val)
956 {
957 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
958 	 * as a negative value.
959 	 */
960 	val = min_t(int, val, INT_MAX / 2);
961 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
962 
963 	/* We double it on the way in to account for "struct sk_buff" etc.
964 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
965 	 * will allow that much actual data to be received on that socket.
966 	 *
967 	 * Applications are unaware that "struct sk_buff" and other overheads
968 	 * allocate from the receive buffer during socket buffer allocation.
969 	 *
970 	 * And after considering the possible alternatives, returning the value
971 	 * we actually used in getsockopt is the most desirable behavior.
972 	 */
973 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
974 }
975 
976 void sock_set_rcvbuf(struct sock *sk, int val)
977 {
978 	lock_sock(sk);
979 	__sock_set_rcvbuf(sk, val);
980 	release_sock(sk);
981 }
982 EXPORT_SYMBOL(sock_set_rcvbuf);
983 
984 static void __sock_set_mark(struct sock *sk, u32 val)
985 {
986 	if (val != sk->sk_mark) {
987 		sk->sk_mark = val;
988 		sk_dst_reset(sk);
989 	}
990 }
991 
992 void sock_set_mark(struct sock *sk, u32 val)
993 {
994 	lock_sock(sk);
995 	__sock_set_mark(sk, val);
996 	release_sock(sk);
997 }
998 EXPORT_SYMBOL(sock_set_mark);
999 
1000 static void sock_release_reserved_memory(struct sock *sk, int bytes)
1001 {
1002 	/* Round down bytes to multiple of pages */
1003 	bytes = round_down(bytes, PAGE_SIZE);
1004 
1005 	WARN_ON(bytes > sk->sk_reserved_mem);
1006 	sk->sk_reserved_mem -= bytes;
1007 	sk_mem_reclaim(sk);
1008 }
1009 
1010 static int sock_reserve_memory(struct sock *sk, int bytes)
1011 {
1012 	long allocated;
1013 	bool charged;
1014 	int pages;
1015 
1016 	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1017 		return -EOPNOTSUPP;
1018 
1019 	if (!bytes)
1020 		return 0;
1021 
1022 	pages = sk_mem_pages(bytes);
1023 
1024 	/* pre-charge to memcg */
1025 	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1026 					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1027 	if (!charged)
1028 		return -ENOMEM;
1029 
1030 	/* pre-charge to forward_alloc */
1031 	sk_memory_allocated_add(sk, pages);
1032 	allocated = sk_memory_allocated(sk);
1033 	/* If the system goes into memory pressure with this
1034 	 * precharge, give up and return error.
1035 	 */
1036 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1037 		sk_memory_allocated_sub(sk, pages);
1038 		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1039 		return -ENOMEM;
1040 	}
1041 	sk->sk_forward_alloc += pages << PAGE_SHIFT;
1042 
1043 	sk->sk_reserved_mem += pages << PAGE_SHIFT;
1044 
1045 	return 0;
1046 }
1047 
1048 void sockopt_lock_sock(struct sock *sk)
1049 {
1050 	/* When current->bpf_ctx is set, the setsockopt is called from
1051 	 * a bpf prog.  bpf has ensured the sk lock has been
1052 	 * acquired before calling setsockopt().
1053 	 */
1054 	if (has_current_bpf_ctx())
1055 		return;
1056 
1057 	lock_sock(sk);
1058 }
1059 EXPORT_SYMBOL(sockopt_lock_sock);
1060 
1061 void sockopt_release_sock(struct sock *sk)
1062 {
1063 	if (has_current_bpf_ctx())
1064 		return;
1065 
1066 	release_sock(sk);
1067 }
1068 EXPORT_SYMBOL(sockopt_release_sock);
1069 
1070 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1071 {
1072 	return has_current_bpf_ctx() || ns_capable(ns, cap);
1073 }
1074 EXPORT_SYMBOL(sockopt_ns_capable);
1075 
1076 bool sockopt_capable(int cap)
1077 {
1078 	return has_current_bpf_ctx() || capable(cap);
1079 }
1080 EXPORT_SYMBOL(sockopt_capable);
1081 
1082 /*
1083  *	This is meant for all protocols to use and covers goings on
1084  *	at the socket level. Everything here is generic.
1085  */
1086 
1087 int sk_setsockopt(struct sock *sk, int level, int optname,
1088 		  sockptr_t optval, unsigned int optlen)
1089 {
1090 	struct so_timestamping timestamping;
1091 	struct socket *sock = sk->sk_socket;
1092 	struct sock_txtime sk_txtime;
1093 	int val;
1094 	int valbool;
1095 	struct linger ling;
1096 	int ret = 0;
1097 
1098 	/*
1099 	 *	Options without arguments
1100 	 */
1101 
1102 	if (optname == SO_BINDTODEVICE)
1103 		return sock_setbindtodevice(sk, optval, optlen);
1104 
1105 	if (optlen < sizeof(int))
1106 		return -EINVAL;
1107 
1108 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1109 		return -EFAULT;
1110 
1111 	valbool = val ? 1 : 0;
1112 
1113 	sockopt_lock_sock(sk);
1114 
1115 	switch (optname) {
1116 	case SO_DEBUG:
1117 		if (val && !sockopt_capable(CAP_NET_ADMIN))
1118 			ret = -EACCES;
1119 		else
1120 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1121 		break;
1122 	case SO_REUSEADDR:
1123 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1124 		break;
1125 	case SO_REUSEPORT:
1126 		sk->sk_reuseport = valbool;
1127 		break;
1128 	case SO_TYPE:
1129 	case SO_PROTOCOL:
1130 	case SO_DOMAIN:
1131 	case SO_ERROR:
1132 		ret = -ENOPROTOOPT;
1133 		break;
1134 	case SO_DONTROUTE:
1135 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1136 		sk_dst_reset(sk);
1137 		break;
1138 	case SO_BROADCAST:
1139 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1140 		break;
1141 	case SO_SNDBUF:
1142 		/* Don't error on this BSD doesn't and if you think
1143 		 * about it this is right. Otherwise apps have to
1144 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1145 		 * are treated in BSD as hints
1146 		 */
1147 		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1148 set_sndbuf:
1149 		/* Ensure val * 2 fits into an int, to prevent max_t()
1150 		 * from treating it as a negative value.
1151 		 */
1152 		val = min_t(int, val, INT_MAX / 2);
1153 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1154 		WRITE_ONCE(sk->sk_sndbuf,
1155 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1156 		/* Wake up sending tasks if we upped the value. */
1157 		sk->sk_write_space(sk);
1158 		break;
1159 
1160 	case SO_SNDBUFFORCE:
1161 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1162 			ret = -EPERM;
1163 			break;
1164 		}
1165 
1166 		/* No negative values (to prevent underflow, as val will be
1167 		 * multiplied by 2).
1168 		 */
1169 		if (val < 0)
1170 			val = 0;
1171 		goto set_sndbuf;
1172 
1173 	case SO_RCVBUF:
1174 		/* Don't error on this BSD doesn't and if you think
1175 		 * about it this is right. Otherwise apps have to
1176 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1177 		 * are treated in BSD as hints
1178 		 */
1179 		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1180 		break;
1181 
1182 	case SO_RCVBUFFORCE:
1183 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1184 			ret = -EPERM;
1185 			break;
1186 		}
1187 
1188 		/* No negative values (to prevent underflow, as val will be
1189 		 * multiplied by 2).
1190 		 */
1191 		__sock_set_rcvbuf(sk, max(val, 0));
1192 		break;
1193 
1194 	case SO_KEEPALIVE:
1195 		if (sk->sk_prot->keepalive)
1196 			sk->sk_prot->keepalive(sk, valbool);
1197 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1198 		break;
1199 
1200 	case SO_OOBINLINE:
1201 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1202 		break;
1203 
1204 	case SO_NO_CHECK:
1205 		sk->sk_no_check_tx = valbool;
1206 		break;
1207 
1208 	case SO_PRIORITY:
1209 		if ((val >= 0 && val <= 6) ||
1210 		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1211 		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1212 			sk->sk_priority = val;
1213 		else
1214 			ret = -EPERM;
1215 		break;
1216 
1217 	case SO_LINGER:
1218 		if (optlen < sizeof(ling)) {
1219 			ret = -EINVAL;	/* 1003.1g */
1220 			break;
1221 		}
1222 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1223 			ret = -EFAULT;
1224 			break;
1225 		}
1226 		if (!ling.l_onoff)
1227 			sock_reset_flag(sk, SOCK_LINGER);
1228 		else {
1229 #if (BITS_PER_LONG == 32)
1230 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
1231 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
1232 			else
1233 #endif
1234 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
1235 			sock_set_flag(sk, SOCK_LINGER);
1236 		}
1237 		break;
1238 
1239 	case SO_BSDCOMPAT:
1240 		break;
1241 
1242 	case SO_PASSCRED:
1243 		if (valbool)
1244 			set_bit(SOCK_PASSCRED, &sock->flags);
1245 		else
1246 			clear_bit(SOCK_PASSCRED, &sock->flags);
1247 		break;
1248 
1249 	case SO_TIMESTAMP_OLD:
1250 	case SO_TIMESTAMP_NEW:
1251 	case SO_TIMESTAMPNS_OLD:
1252 	case SO_TIMESTAMPNS_NEW:
1253 		sock_set_timestamp(sk, optname, valbool);
1254 		break;
1255 
1256 	case SO_TIMESTAMPING_NEW:
1257 	case SO_TIMESTAMPING_OLD:
1258 		if (optlen == sizeof(timestamping)) {
1259 			if (copy_from_sockptr(&timestamping, optval,
1260 					      sizeof(timestamping))) {
1261 				ret = -EFAULT;
1262 				break;
1263 			}
1264 		} else {
1265 			memset(&timestamping, 0, sizeof(timestamping));
1266 			timestamping.flags = val;
1267 		}
1268 		ret = sock_set_timestamping(sk, optname, timestamping);
1269 		break;
1270 
1271 	case SO_RCVLOWAT:
1272 		if (val < 0)
1273 			val = INT_MAX;
1274 		if (sock && sock->ops->set_rcvlowat)
1275 			ret = sock->ops->set_rcvlowat(sk, val);
1276 		else
1277 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1278 		break;
1279 
1280 	case SO_RCVTIMEO_OLD:
1281 	case SO_RCVTIMEO_NEW:
1282 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1283 				       optlen, optname == SO_RCVTIMEO_OLD);
1284 		break;
1285 
1286 	case SO_SNDTIMEO_OLD:
1287 	case SO_SNDTIMEO_NEW:
1288 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1289 				       optlen, optname == SO_SNDTIMEO_OLD);
1290 		break;
1291 
1292 	case SO_ATTACH_FILTER: {
1293 		struct sock_fprog fprog;
1294 
1295 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1296 		if (!ret)
1297 			ret = sk_attach_filter(&fprog, sk);
1298 		break;
1299 	}
1300 	case SO_ATTACH_BPF:
1301 		ret = -EINVAL;
1302 		if (optlen == sizeof(u32)) {
1303 			u32 ufd;
1304 
1305 			ret = -EFAULT;
1306 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1307 				break;
1308 
1309 			ret = sk_attach_bpf(ufd, sk);
1310 		}
1311 		break;
1312 
1313 	case SO_ATTACH_REUSEPORT_CBPF: {
1314 		struct sock_fprog fprog;
1315 
1316 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1317 		if (!ret)
1318 			ret = sk_reuseport_attach_filter(&fprog, sk);
1319 		break;
1320 	}
1321 	case SO_ATTACH_REUSEPORT_EBPF:
1322 		ret = -EINVAL;
1323 		if (optlen == sizeof(u32)) {
1324 			u32 ufd;
1325 
1326 			ret = -EFAULT;
1327 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1328 				break;
1329 
1330 			ret = sk_reuseport_attach_bpf(ufd, sk);
1331 		}
1332 		break;
1333 
1334 	case SO_DETACH_REUSEPORT_BPF:
1335 		ret = reuseport_detach_prog(sk);
1336 		break;
1337 
1338 	case SO_DETACH_FILTER:
1339 		ret = sk_detach_filter(sk);
1340 		break;
1341 
1342 	case SO_LOCK_FILTER:
1343 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1344 			ret = -EPERM;
1345 		else
1346 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1347 		break;
1348 
1349 	case SO_PASSSEC:
1350 		if (valbool)
1351 			set_bit(SOCK_PASSSEC, &sock->flags);
1352 		else
1353 			clear_bit(SOCK_PASSSEC, &sock->flags);
1354 		break;
1355 	case SO_MARK:
1356 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1357 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1358 			ret = -EPERM;
1359 			break;
1360 		}
1361 
1362 		__sock_set_mark(sk, val);
1363 		break;
1364 	case SO_RCVMARK:
1365 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1366 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1367 			ret = -EPERM;
1368 			break;
1369 		}
1370 
1371 		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1372 		break;
1373 
1374 	case SO_RXQ_OVFL:
1375 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1376 		break;
1377 
1378 	case SO_WIFI_STATUS:
1379 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1380 		break;
1381 
1382 	case SO_PEEK_OFF:
1383 		if (sock->ops->set_peek_off)
1384 			ret = sock->ops->set_peek_off(sk, val);
1385 		else
1386 			ret = -EOPNOTSUPP;
1387 		break;
1388 
1389 	case SO_NOFCS:
1390 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1391 		break;
1392 
1393 	case SO_SELECT_ERR_QUEUE:
1394 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1395 		break;
1396 
1397 #ifdef CONFIG_NET_RX_BUSY_POLL
1398 	case SO_BUSY_POLL:
1399 		if (val < 0)
1400 			ret = -EINVAL;
1401 		else
1402 			WRITE_ONCE(sk->sk_ll_usec, val);
1403 		break;
1404 	case SO_PREFER_BUSY_POLL:
1405 		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1406 			ret = -EPERM;
1407 		else
1408 			WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1409 		break;
1410 	case SO_BUSY_POLL_BUDGET:
1411 		if (val > READ_ONCE(sk->sk_busy_poll_budget) && !sockopt_capable(CAP_NET_ADMIN)) {
1412 			ret = -EPERM;
1413 		} else {
1414 			if (val < 0 || val > U16_MAX)
1415 				ret = -EINVAL;
1416 			else
1417 				WRITE_ONCE(sk->sk_busy_poll_budget, val);
1418 		}
1419 		break;
1420 #endif
1421 
1422 	case SO_MAX_PACING_RATE:
1423 		{
1424 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1425 
1426 		if (sizeof(ulval) != sizeof(val) &&
1427 		    optlen >= sizeof(ulval) &&
1428 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1429 			ret = -EFAULT;
1430 			break;
1431 		}
1432 		if (ulval != ~0UL)
1433 			cmpxchg(&sk->sk_pacing_status,
1434 				SK_PACING_NONE,
1435 				SK_PACING_NEEDED);
1436 		sk->sk_max_pacing_rate = ulval;
1437 		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1438 		break;
1439 		}
1440 	case SO_INCOMING_CPU:
1441 		reuseport_update_incoming_cpu(sk, val);
1442 		break;
1443 
1444 	case SO_CNX_ADVICE:
1445 		if (val == 1)
1446 			dst_negative_advice(sk);
1447 		break;
1448 
1449 	case SO_ZEROCOPY:
1450 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1451 			if (!(sk_is_tcp(sk) ||
1452 			      (sk->sk_type == SOCK_DGRAM &&
1453 			       sk->sk_protocol == IPPROTO_UDP)))
1454 				ret = -EOPNOTSUPP;
1455 		} else if (sk->sk_family != PF_RDS) {
1456 			ret = -EOPNOTSUPP;
1457 		}
1458 		if (!ret) {
1459 			if (val < 0 || val > 1)
1460 				ret = -EINVAL;
1461 			else
1462 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1463 		}
1464 		break;
1465 
1466 	case SO_TXTIME:
1467 		if (optlen != sizeof(struct sock_txtime)) {
1468 			ret = -EINVAL;
1469 			break;
1470 		} else if (copy_from_sockptr(&sk_txtime, optval,
1471 			   sizeof(struct sock_txtime))) {
1472 			ret = -EFAULT;
1473 			break;
1474 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1475 			ret = -EINVAL;
1476 			break;
1477 		}
1478 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1479 		 * scheduler has enough safe guards.
1480 		 */
1481 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1482 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1483 			ret = -EPERM;
1484 			break;
1485 		}
1486 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1487 		sk->sk_clockid = sk_txtime.clockid;
1488 		sk->sk_txtime_deadline_mode =
1489 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1490 		sk->sk_txtime_report_errors =
1491 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1492 		break;
1493 
1494 	case SO_BINDTOIFINDEX:
1495 		ret = sock_bindtoindex_locked(sk, val);
1496 		break;
1497 
1498 	case SO_BUF_LOCK:
1499 		if (val & ~SOCK_BUF_LOCK_MASK) {
1500 			ret = -EINVAL;
1501 			break;
1502 		}
1503 		sk->sk_userlocks = val | (sk->sk_userlocks &
1504 					  ~SOCK_BUF_LOCK_MASK);
1505 		break;
1506 
1507 	case SO_RESERVE_MEM:
1508 	{
1509 		int delta;
1510 
1511 		if (val < 0) {
1512 			ret = -EINVAL;
1513 			break;
1514 		}
1515 
1516 		delta = val - sk->sk_reserved_mem;
1517 		if (delta < 0)
1518 			sock_release_reserved_memory(sk, -delta);
1519 		else
1520 			ret = sock_reserve_memory(sk, delta);
1521 		break;
1522 	}
1523 
1524 	case SO_TXREHASH:
1525 		if (val < -1 || val > 1) {
1526 			ret = -EINVAL;
1527 			break;
1528 		}
1529 		if ((u8)val == SOCK_TXREHASH_DEFAULT)
1530 			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1531 		/* Paired with READ_ONCE() in tcp_rtx_synack() */
1532 		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1533 		break;
1534 
1535 	default:
1536 		ret = -ENOPROTOOPT;
1537 		break;
1538 	}
1539 	sockopt_release_sock(sk);
1540 	return ret;
1541 }
1542 
1543 int sock_setsockopt(struct socket *sock, int level, int optname,
1544 		    sockptr_t optval, unsigned int optlen)
1545 {
1546 	return sk_setsockopt(sock->sk, level, optname,
1547 			     optval, optlen);
1548 }
1549 EXPORT_SYMBOL(sock_setsockopt);
1550 
1551 static const struct cred *sk_get_peer_cred(struct sock *sk)
1552 {
1553 	const struct cred *cred;
1554 
1555 	spin_lock(&sk->sk_peer_lock);
1556 	cred = get_cred(sk->sk_peer_cred);
1557 	spin_unlock(&sk->sk_peer_lock);
1558 
1559 	return cred;
1560 }
1561 
1562 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1563 			  struct ucred *ucred)
1564 {
1565 	ucred->pid = pid_vnr(pid);
1566 	ucred->uid = ucred->gid = -1;
1567 	if (cred) {
1568 		struct user_namespace *current_ns = current_user_ns();
1569 
1570 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1571 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1572 	}
1573 }
1574 
1575 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1576 {
1577 	struct user_namespace *user_ns = current_user_ns();
1578 	int i;
1579 
1580 	for (i = 0; i < src->ngroups; i++) {
1581 		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1582 
1583 		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1584 			return -EFAULT;
1585 	}
1586 
1587 	return 0;
1588 }
1589 
1590 int sk_getsockopt(struct sock *sk, int level, int optname,
1591 		  sockptr_t optval, sockptr_t optlen)
1592 {
1593 	struct socket *sock = sk->sk_socket;
1594 
1595 	union {
1596 		int val;
1597 		u64 val64;
1598 		unsigned long ulval;
1599 		struct linger ling;
1600 		struct old_timeval32 tm32;
1601 		struct __kernel_old_timeval tm;
1602 		struct  __kernel_sock_timeval stm;
1603 		struct sock_txtime txtime;
1604 		struct so_timestamping timestamping;
1605 	} v;
1606 
1607 	int lv = sizeof(int);
1608 	int len;
1609 
1610 	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1611 		return -EFAULT;
1612 	if (len < 0)
1613 		return -EINVAL;
1614 
1615 	memset(&v, 0, sizeof(v));
1616 
1617 	switch (optname) {
1618 	case SO_DEBUG:
1619 		v.val = sock_flag(sk, SOCK_DBG);
1620 		break;
1621 
1622 	case SO_DONTROUTE:
1623 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1624 		break;
1625 
1626 	case SO_BROADCAST:
1627 		v.val = sock_flag(sk, SOCK_BROADCAST);
1628 		break;
1629 
1630 	case SO_SNDBUF:
1631 		v.val = sk->sk_sndbuf;
1632 		break;
1633 
1634 	case SO_RCVBUF:
1635 		v.val = sk->sk_rcvbuf;
1636 		break;
1637 
1638 	case SO_REUSEADDR:
1639 		v.val = sk->sk_reuse;
1640 		break;
1641 
1642 	case SO_REUSEPORT:
1643 		v.val = sk->sk_reuseport;
1644 		break;
1645 
1646 	case SO_KEEPALIVE:
1647 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1648 		break;
1649 
1650 	case SO_TYPE:
1651 		v.val = sk->sk_type;
1652 		break;
1653 
1654 	case SO_PROTOCOL:
1655 		v.val = sk->sk_protocol;
1656 		break;
1657 
1658 	case SO_DOMAIN:
1659 		v.val = sk->sk_family;
1660 		break;
1661 
1662 	case SO_ERROR:
1663 		v.val = -sock_error(sk);
1664 		if (v.val == 0)
1665 			v.val = xchg(&sk->sk_err_soft, 0);
1666 		break;
1667 
1668 	case SO_OOBINLINE:
1669 		v.val = sock_flag(sk, SOCK_URGINLINE);
1670 		break;
1671 
1672 	case SO_NO_CHECK:
1673 		v.val = sk->sk_no_check_tx;
1674 		break;
1675 
1676 	case SO_PRIORITY:
1677 		v.val = sk->sk_priority;
1678 		break;
1679 
1680 	case SO_LINGER:
1681 		lv		= sizeof(v.ling);
1682 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1683 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1684 		break;
1685 
1686 	case SO_BSDCOMPAT:
1687 		break;
1688 
1689 	case SO_TIMESTAMP_OLD:
1690 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1691 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1692 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1693 		break;
1694 
1695 	case SO_TIMESTAMPNS_OLD:
1696 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1697 		break;
1698 
1699 	case SO_TIMESTAMP_NEW:
1700 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1701 		break;
1702 
1703 	case SO_TIMESTAMPNS_NEW:
1704 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1705 		break;
1706 
1707 	case SO_TIMESTAMPING_OLD:
1708 		lv = sizeof(v.timestamping);
1709 		v.timestamping.flags = sk->sk_tsflags;
1710 		v.timestamping.bind_phc = sk->sk_bind_phc;
1711 		break;
1712 
1713 	case SO_RCVTIMEO_OLD:
1714 	case SO_RCVTIMEO_NEW:
1715 		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1716 		break;
1717 
1718 	case SO_SNDTIMEO_OLD:
1719 	case SO_SNDTIMEO_NEW:
1720 		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1721 		break;
1722 
1723 	case SO_RCVLOWAT:
1724 		v.val = sk->sk_rcvlowat;
1725 		break;
1726 
1727 	case SO_SNDLOWAT:
1728 		v.val = 1;
1729 		break;
1730 
1731 	case SO_PASSCRED:
1732 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1733 		break;
1734 
1735 	case SO_PEERCRED:
1736 	{
1737 		struct ucred peercred;
1738 		if (len > sizeof(peercred))
1739 			len = sizeof(peercred);
1740 
1741 		spin_lock(&sk->sk_peer_lock);
1742 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1743 		spin_unlock(&sk->sk_peer_lock);
1744 
1745 		if (copy_to_sockptr(optval, &peercred, len))
1746 			return -EFAULT;
1747 		goto lenout;
1748 	}
1749 
1750 	case SO_PEERGROUPS:
1751 	{
1752 		const struct cred *cred;
1753 		int ret, n;
1754 
1755 		cred = sk_get_peer_cred(sk);
1756 		if (!cred)
1757 			return -ENODATA;
1758 
1759 		n = cred->group_info->ngroups;
1760 		if (len < n * sizeof(gid_t)) {
1761 			len = n * sizeof(gid_t);
1762 			put_cred(cred);
1763 			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1764 		}
1765 		len = n * sizeof(gid_t);
1766 
1767 		ret = groups_to_user(optval, cred->group_info);
1768 		put_cred(cred);
1769 		if (ret)
1770 			return ret;
1771 		goto lenout;
1772 	}
1773 
1774 	case SO_PEERNAME:
1775 	{
1776 		char address[128];
1777 
1778 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1779 		if (lv < 0)
1780 			return -ENOTCONN;
1781 		if (lv < len)
1782 			return -EINVAL;
1783 		if (copy_to_sockptr(optval, address, len))
1784 			return -EFAULT;
1785 		goto lenout;
1786 	}
1787 
1788 	/* Dubious BSD thing... Probably nobody even uses it, but
1789 	 * the UNIX standard wants it for whatever reason... -DaveM
1790 	 */
1791 	case SO_ACCEPTCONN:
1792 		v.val = sk->sk_state == TCP_LISTEN;
1793 		break;
1794 
1795 	case SO_PASSSEC:
1796 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1797 		break;
1798 
1799 	case SO_PEERSEC:
1800 		return security_socket_getpeersec_stream(sock,
1801 							 optval, optlen, len);
1802 
1803 	case SO_MARK:
1804 		v.val = sk->sk_mark;
1805 		break;
1806 
1807 	case SO_RCVMARK:
1808 		v.val = sock_flag(sk, SOCK_RCVMARK);
1809 		break;
1810 
1811 	case SO_RXQ_OVFL:
1812 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1813 		break;
1814 
1815 	case SO_WIFI_STATUS:
1816 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1817 		break;
1818 
1819 	case SO_PEEK_OFF:
1820 		if (!sock->ops->set_peek_off)
1821 			return -EOPNOTSUPP;
1822 
1823 		v.val = sk->sk_peek_off;
1824 		break;
1825 	case SO_NOFCS:
1826 		v.val = sock_flag(sk, SOCK_NOFCS);
1827 		break;
1828 
1829 	case SO_BINDTODEVICE:
1830 		return sock_getbindtodevice(sk, optval, optlen, len);
1831 
1832 	case SO_GET_FILTER:
1833 		len = sk_get_filter(sk, optval, len);
1834 		if (len < 0)
1835 			return len;
1836 
1837 		goto lenout;
1838 
1839 	case SO_LOCK_FILTER:
1840 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1841 		break;
1842 
1843 	case SO_BPF_EXTENSIONS:
1844 		v.val = bpf_tell_extensions();
1845 		break;
1846 
1847 	case SO_SELECT_ERR_QUEUE:
1848 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1849 		break;
1850 
1851 #ifdef CONFIG_NET_RX_BUSY_POLL
1852 	case SO_BUSY_POLL:
1853 		v.val = sk->sk_ll_usec;
1854 		break;
1855 	case SO_PREFER_BUSY_POLL:
1856 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1857 		break;
1858 #endif
1859 
1860 	case SO_MAX_PACING_RATE:
1861 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1862 			lv = sizeof(v.ulval);
1863 			v.ulval = sk->sk_max_pacing_rate;
1864 		} else {
1865 			/* 32bit version */
1866 			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1867 		}
1868 		break;
1869 
1870 	case SO_INCOMING_CPU:
1871 		v.val = READ_ONCE(sk->sk_incoming_cpu);
1872 		break;
1873 
1874 	case SO_MEMINFO:
1875 	{
1876 		u32 meminfo[SK_MEMINFO_VARS];
1877 
1878 		sk_get_meminfo(sk, meminfo);
1879 
1880 		len = min_t(unsigned int, len, sizeof(meminfo));
1881 		if (copy_to_sockptr(optval, &meminfo, len))
1882 			return -EFAULT;
1883 
1884 		goto lenout;
1885 	}
1886 
1887 #ifdef CONFIG_NET_RX_BUSY_POLL
1888 	case SO_INCOMING_NAPI_ID:
1889 		v.val = READ_ONCE(sk->sk_napi_id);
1890 
1891 		/* aggregate non-NAPI IDs down to 0 */
1892 		if (v.val < MIN_NAPI_ID)
1893 			v.val = 0;
1894 
1895 		break;
1896 #endif
1897 
1898 	case SO_COOKIE:
1899 		lv = sizeof(u64);
1900 		if (len < lv)
1901 			return -EINVAL;
1902 		v.val64 = sock_gen_cookie(sk);
1903 		break;
1904 
1905 	case SO_ZEROCOPY:
1906 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1907 		break;
1908 
1909 	case SO_TXTIME:
1910 		lv = sizeof(v.txtime);
1911 		v.txtime.clockid = sk->sk_clockid;
1912 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1913 				  SOF_TXTIME_DEADLINE_MODE : 0;
1914 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1915 				  SOF_TXTIME_REPORT_ERRORS : 0;
1916 		break;
1917 
1918 	case SO_BINDTOIFINDEX:
1919 		v.val = READ_ONCE(sk->sk_bound_dev_if);
1920 		break;
1921 
1922 	case SO_NETNS_COOKIE:
1923 		lv = sizeof(u64);
1924 		if (len != lv)
1925 			return -EINVAL;
1926 		v.val64 = sock_net(sk)->net_cookie;
1927 		break;
1928 
1929 	case SO_BUF_LOCK:
1930 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1931 		break;
1932 
1933 	case SO_RESERVE_MEM:
1934 		v.val = sk->sk_reserved_mem;
1935 		break;
1936 
1937 	case SO_TXREHASH:
1938 		v.val = sk->sk_txrehash;
1939 		break;
1940 
1941 	default:
1942 		/* We implement the SO_SNDLOWAT etc to not be settable
1943 		 * (1003.1g 7).
1944 		 */
1945 		return -ENOPROTOOPT;
1946 	}
1947 
1948 	if (len > lv)
1949 		len = lv;
1950 	if (copy_to_sockptr(optval, &v, len))
1951 		return -EFAULT;
1952 lenout:
1953 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
1954 		return -EFAULT;
1955 	return 0;
1956 }
1957 
1958 int sock_getsockopt(struct socket *sock, int level, int optname,
1959 		    char __user *optval, int __user *optlen)
1960 {
1961 	return sk_getsockopt(sock->sk, level, optname,
1962 			     USER_SOCKPTR(optval),
1963 			     USER_SOCKPTR(optlen));
1964 }
1965 
1966 /*
1967  * Initialize an sk_lock.
1968  *
1969  * (We also register the sk_lock with the lock validator.)
1970  */
1971 static inline void sock_lock_init(struct sock *sk)
1972 {
1973 	if (sk->sk_kern_sock)
1974 		sock_lock_init_class_and_name(
1975 			sk,
1976 			af_family_kern_slock_key_strings[sk->sk_family],
1977 			af_family_kern_slock_keys + sk->sk_family,
1978 			af_family_kern_key_strings[sk->sk_family],
1979 			af_family_kern_keys + sk->sk_family);
1980 	else
1981 		sock_lock_init_class_and_name(
1982 			sk,
1983 			af_family_slock_key_strings[sk->sk_family],
1984 			af_family_slock_keys + sk->sk_family,
1985 			af_family_key_strings[sk->sk_family],
1986 			af_family_keys + sk->sk_family);
1987 }
1988 
1989 /*
1990  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1991  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1992  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1993  */
1994 static void sock_copy(struct sock *nsk, const struct sock *osk)
1995 {
1996 	const struct proto *prot = READ_ONCE(osk->sk_prot);
1997 #ifdef CONFIG_SECURITY_NETWORK
1998 	void *sptr = nsk->sk_security;
1999 #endif
2000 
2001 	/* If we move sk_tx_queue_mapping out of the private section,
2002 	 * we must check if sk_tx_queue_clear() is called after
2003 	 * sock_copy() in sk_clone_lock().
2004 	 */
2005 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2006 		     offsetof(struct sock, sk_dontcopy_begin) ||
2007 		     offsetof(struct sock, sk_tx_queue_mapping) >=
2008 		     offsetof(struct sock, sk_dontcopy_end));
2009 
2010 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2011 
2012 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2013 	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
2014 
2015 #ifdef CONFIG_SECURITY_NETWORK
2016 	nsk->sk_security = sptr;
2017 	security_sk_clone(osk, nsk);
2018 #endif
2019 }
2020 
2021 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2022 		int family)
2023 {
2024 	struct sock *sk;
2025 	struct kmem_cache *slab;
2026 
2027 	slab = prot->slab;
2028 	if (slab != NULL) {
2029 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2030 		if (!sk)
2031 			return sk;
2032 		if (want_init_on_alloc(priority))
2033 			sk_prot_clear_nulls(sk, prot->obj_size);
2034 	} else
2035 		sk = kmalloc(prot->obj_size, priority);
2036 
2037 	if (sk != NULL) {
2038 		if (security_sk_alloc(sk, family, priority))
2039 			goto out_free;
2040 
2041 		if (!try_module_get(prot->owner))
2042 			goto out_free_sec;
2043 	}
2044 
2045 	return sk;
2046 
2047 out_free_sec:
2048 	security_sk_free(sk);
2049 out_free:
2050 	if (slab != NULL)
2051 		kmem_cache_free(slab, sk);
2052 	else
2053 		kfree(sk);
2054 	return NULL;
2055 }
2056 
2057 static void sk_prot_free(struct proto *prot, struct sock *sk)
2058 {
2059 	struct kmem_cache *slab;
2060 	struct module *owner;
2061 
2062 	owner = prot->owner;
2063 	slab = prot->slab;
2064 
2065 	cgroup_sk_free(&sk->sk_cgrp_data);
2066 	mem_cgroup_sk_free(sk);
2067 	security_sk_free(sk);
2068 	if (slab != NULL)
2069 		kmem_cache_free(slab, sk);
2070 	else
2071 		kfree(sk);
2072 	module_put(owner);
2073 }
2074 
2075 /**
2076  *	sk_alloc - All socket objects are allocated here
2077  *	@net: the applicable net namespace
2078  *	@family: protocol family
2079  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2080  *	@prot: struct proto associated with this new sock instance
2081  *	@kern: is this to be a kernel socket?
2082  */
2083 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2084 		      struct proto *prot, int kern)
2085 {
2086 	struct sock *sk;
2087 
2088 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2089 	if (sk) {
2090 		sk->sk_family = family;
2091 		/*
2092 		 * See comment in struct sock definition to understand
2093 		 * why we need sk_prot_creator -acme
2094 		 */
2095 		sk->sk_prot = sk->sk_prot_creator = prot;
2096 		sk->sk_kern_sock = kern;
2097 		sock_lock_init(sk);
2098 		sk->sk_net_refcnt = kern ? 0 : 1;
2099 		if (likely(sk->sk_net_refcnt)) {
2100 			get_net_track(net, &sk->ns_tracker, priority);
2101 			sock_inuse_add(net, 1);
2102 		} else {
2103 			__netns_tracker_alloc(net, &sk->ns_tracker,
2104 					      false, priority);
2105 		}
2106 
2107 		sock_net_set(sk, net);
2108 		refcount_set(&sk->sk_wmem_alloc, 1);
2109 
2110 		mem_cgroup_sk_alloc(sk);
2111 		cgroup_sk_alloc(&sk->sk_cgrp_data);
2112 		sock_update_classid(&sk->sk_cgrp_data);
2113 		sock_update_netprioidx(&sk->sk_cgrp_data);
2114 		sk_tx_queue_clear(sk);
2115 	}
2116 
2117 	return sk;
2118 }
2119 EXPORT_SYMBOL(sk_alloc);
2120 
2121 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2122  * grace period. This is the case for UDP sockets and TCP listeners.
2123  */
2124 static void __sk_destruct(struct rcu_head *head)
2125 {
2126 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2127 	struct sk_filter *filter;
2128 
2129 	if (sk->sk_destruct)
2130 		sk->sk_destruct(sk);
2131 
2132 	filter = rcu_dereference_check(sk->sk_filter,
2133 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2134 	if (filter) {
2135 		sk_filter_uncharge(sk, filter);
2136 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2137 	}
2138 
2139 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2140 
2141 #ifdef CONFIG_BPF_SYSCALL
2142 	bpf_sk_storage_free(sk);
2143 #endif
2144 
2145 	if (atomic_read(&sk->sk_omem_alloc))
2146 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2147 			 __func__, atomic_read(&sk->sk_omem_alloc));
2148 
2149 	if (sk->sk_frag.page) {
2150 		put_page(sk->sk_frag.page);
2151 		sk->sk_frag.page = NULL;
2152 	}
2153 
2154 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2155 	put_cred(sk->sk_peer_cred);
2156 	put_pid(sk->sk_peer_pid);
2157 
2158 	if (likely(sk->sk_net_refcnt))
2159 		put_net_track(sock_net(sk), &sk->ns_tracker);
2160 	else
2161 		__netns_tracker_free(sock_net(sk), &sk->ns_tracker, false);
2162 
2163 	sk_prot_free(sk->sk_prot_creator, sk);
2164 }
2165 
2166 void sk_destruct(struct sock *sk)
2167 {
2168 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2169 
2170 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2171 		reuseport_detach_sock(sk);
2172 		use_call_rcu = true;
2173 	}
2174 
2175 	if (use_call_rcu)
2176 		call_rcu(&sk->sk_rcu, __sk_destruct);
2177 	else
2178 		__sk_destruct(&sk->sk_rcu);
2179 }
2180 
2181 static void __sk_free(struct sock *sk)
2182 {
2183 	if (likely(sk->sk_net_refcnt))
2184 		sock_inuse_add(sock_net(sk), -1);
2185 
2186 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2187 		sock_diag_broadcast_destroy(sk);
2188 	else
2189 		sk_destruct(sk);
2190 }
2191 
2192 void sk_free(struct sock *sk)
2193 {
2194 	/*
2195 	 * We subtract one from sk_wmem_alloc and can know if
2196 	 * some packets are still in some tx queue.
2197 	 * If not null, sock_wfree() will call __sk_free(sk) later
2198 	 */
2199 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2200 		__sk_free(sk);
2201 }
2202 EXPORT_SYMBOL(sk_free);
2203 
2204 static void sk_init_common(struct sock *sk)
2205 {
2206 	skb_queue_head_init(&sk->sk_receive_queue);
2207 	skb_queue_head_init(&sk->sk_write_queue);
2208 	skb_queue_head_init(&sk->sk_error_queue);
2209 
2210 	rwlock_init(&sk->sk_callback_lock);
2211 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2212 			af_rlock_keys + sk->sk_family,
2213 			af_family_rlock_key_strings[sk->sk_family]);
2214 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2215 			af_wlock_keys + sk->sk_family,
2216 			af_family_wlock_key_strings[sk->sk_family]);
2217 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2218 			af_elock_keys + sk->sk_family,
2219 			af_family_elock_key_strings[sk->sk_family]);
2220 	lockdep_set_class_and_name(&sk->sk_callback_lock,
2221 			af_callback_keys + sk->sk_family,
2222 			af_family_clock_key_strings[sk->sk_family]);
2223 }
2224 
2225 /**
2226  *	sk_clone_lock - clone a socket, and lock its clone
2227  *	@sk: the socket to clone
2228  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2229  *
2230  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2231  */
2232 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2233 {
2234 	struct proto *prot = READ_ONCE(sk->sk_prot);
2235 	struct sk_filter *filter;
2236 	bool is_charged = true;
2237 	struct sock *newsk;
2238 
2239 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2240 	if (!newsk)
2241 		goto out;
2242 
2243 	sock_copy(newsk, sk);
2244 
2245 	newsk->sk_prot_creator = prot;
2246 
2247 	/* SANITY */
2248 	if (likely(newsk->sk_net_refcnt)) {
2249 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2250 		sock_inuse_add(sock_net(newsk), 1);
2251 	} else {
2252 		/* Kernel sockets are not elevating the struct net refcount.
2253 		 * Instead, use a tracker to more easily detect if a layer
2254 		 * is not properly dismantling its kernel sockets at netns
2255 		 * destroy time.
2256 		 */
2257 		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2258 				      false, priority);
2259 	}
2260 	sk_node_init(&newsk->sk_node);
2261 	sock_lock_init(newsk);
2262 	bh_lock_sock(newsk);
2263 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2264 	newsk->sk_backlog.len = 0;
2265 
2266 	atomic_set(&newsk->sk_rmem_alloc, 0);
2267 
2268 	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2269 	refcount_set(&newsk->sk_wmem_alloc, 1);
2270 
2271 	atomic_set(&newsk->sk_omem_alloc, 0);
2272 	sk_init_common(newsk);
2273 
2274 	newsk->sk_dst_cache	= NULL;
2275 	newsk->sk_dst_pending_confirm = 0;
2276 	newsk->sk_wmem_queued	= 0;
2277 	newsk->sk_forward_alloc = 0;
2278 	newsk->sk_reserved_mem  = 0;
2279 	atomic_set(&newsk->sk_drops, 0);
2280 	newsk->sk_send_head	= NULL;
2281 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2282 	atomic_set(&newsk->sk_zckey, 0);
2283 
2284 	sock_reset_flag(newsk, SOCK_DONE);
2285 
2286 	/* sk->sk_memcg will be populated at accept() time */
2287 	newsk->sk_memcg = NULL;
2288 
2289 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2290 
2291 	rcu_read_lock();
2292 	filter = rcu_dereference(sk->sk_filter);
2293 	if (filter != NULL)
2294 		/* though it's an empty new sock, the charging may fail
2295 		 * if sysctl_optmem_max was changed between creation of
2296 		 * original socket and cloning
2297 		 */
2298 		is_charged = sk_filter_charge(newsk, filter);
2299 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2300 	rcu_read_unlock();
2301 
2302 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2303 		/* We need to make sure that we don't uncharge the new
2304 		 * socket if we couldn't charge it in the first place
2305 		 * as otherwise we uncharge the parent's filter.
2306 		 */
2307 		if (!is_charged)
2308 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2309 		sk_free_unlock_clone(newsk);
2310 		newsk = NULL;
2311 		goto out;
2312 	}
2313 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2314 
2315 	if (bpf_sk_storage_clone(sk, newsk)) {
2316 		sk_free_unlock_clone(newsk);
2317 		newsk = NULL;
2318 		goto out;
2319 	}
2320 
2321 	/* Clear sk_user_data if parent had the pointer tagged
2322 	 * as not suitable for copying when cloning.
2323 	 */
2324 	if (sk_user_data_is_nocopy(newsk))
2325 		newsk->sk_user_data = NULL;
2326 
2327 	newsk->sk_err	   = 0;
2328 	newsk->sk_err_soft = 0;
2329 	newsk->sk_priority = 0;
2330 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2331 
2332 	/* Before updating sk_refcnt, we must commit prior changes to memory
2333 	 * (Documentation/RCU/rculist_nulls.rst for details)
2334 	 */
2335 	smp_wmb();
2336 	refcount_set(&newsk->sk_refcnt, 2);
2337 
2338 	sk_set_socket(newsk, NULL);
2339 	sk_tx_queue_clear(newsk);
2340 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2341 
2342 	if (newsk->sk_prot->sockets_allocated)
2343 		sk_sockets_allocated_inc(newsk);
2344 
2345 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2346 		net_enable_timestamp();
2347 out:
2348 	return newsk;
2349 }
2350 EXPORT_SYMBOL_GPL(sk_clone_lock);
2351 
2352 void sk_free_unlock_clone(struct sock *sk)
2353 {
2354 	/* It is still raw copy of parent, so invalidate
2355 	 * destructor and make plain sk_free() */
2356 	sk->sk_destruct = NULL;
2357 	bh_unlock_sock(sk);
2358 	sk_free(sk);
2359 }
2360 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2361 
2362 static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst)
2363 {
2364 	bool is_ipv6 = false;
2365 	u32 max_size;
2366 
2367 #if IS_ENABLED(CONFIG_IPV6)
2368 	is_ipv6 = (sk->sk_family == AF_INET6 &&
2369 		   !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2370 #endif
2371 	/* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2372 	max_size = is_ipv6 ? READ_ONCE(dst->dev->gso_max_size) :
2373 			READ_ONCE(dst->dev->gso_ipv4_max_size);
2374 	if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2375 		max_size = GSO_LEGACY_MAX_SIZE;
2376 
2377 	return max_size - (MAX_TCP_HEADER + 1);
2378 }
2379 
2380 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2381 {
2382 	u32 max_segs = 1;
2383 
2384 	sk->sk_route_caps = dst->dev->features;
2385 	if (sk_is_tcp(sk))
2386 		sk->sk_route_caps |= NETIF_F_GSO;
2387 	if (sk->sk_route_caps & NETIF_F_GSO)
2388 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2389 	if (unlikely(sk->sk_gso_disabled))
2390 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2391 	if (sk_can_gso(sk)) {
2392 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2393 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2394 		} else {
2395 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2396 			sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst);
2397 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2398 			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2399 		}
2400 	}
2401 	sk->sk_gso_max_segs = max_segs;
2402 	sk_dst_set(sk, dst);
2403 }
2404 EXPORT_SYMBOL_GPL(sk_setup_caps);
2405 
2406 /*
2407  *	Simple resource managers for sockets.
2408  */
2409 
2410 
2411 /*
2412  * Write buffer destructor automatically called from kfree_skb.
2413  */
2414 void sock_wfree(struct sk_buff *skb)
2415 {
2416 	struct sock *sk = skb->sk;
2417 	unsigned int len = skb->truesize;
2418 	bool free;
2419 
2420 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2421 		if (sock_flag(sk, SOCK_RCU_FREE) &&
2422 		    sk->sk_write_space == sock_def_write_space) {
2423 			rcu_read_lock();
2424 			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2425 			sock_def_write_space_wfree(sk);
2426 			rcu_read_unlock();
2427 			if (unlikely(free))
2428 				__sk_free(sk);
2429 			return;
2430 		}
2431 
2432 		/*
2433 		 * Keep a reference on sk_wmem_alloc, this will be released
2434 		 * after sk_write_space() call
2435 		 */
2436 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2437 		sk->sk_write_space(sk);
2438 		len = 1;
2439 	}
2440 	/*
2441 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2442 	 * could not do because of in-flight packets
2443 	 */
2444 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2445 		__sk_free(sk);
2446 }
2447 EXPORT_SYMBOL(sock_wfree);
2448 
2449 /* This variant of sock_wfree() is used by TCP,
2450  * since it sets SOCK_USE_WRITE_QUEUE.
2451  */
2452 void __sock_wfree(struct sk_buff *skb)
2453 {
2454 	struct sock *sk = skb->sk;
2455 
2456 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2457 		__sk_free(sk);
2458 }
2459 
2460 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2461 {
2462 	skb_orphan(skb);
2463 	skb->sk = sk;
2464 #ifdef CONFIG_INET
2465 	if (unlikely(!sk_fullsock(sk))) {
2466 		skb->destructor = sock_edemux;
2467 		sock_hold(sk);
2468 		return;
2469 	}
2470 #endif
2471 	skb->destructor = sock_wfree;
2472 	skb_set_hash_from_sk(skb, sk);
2473 	/*
2474 	 * We used to take a refcount on sk, but following operation
2475 	 * is enough to guarantee sk_free() wont free this sock until
2476 	 * all in-flight packets are completed
2477 	 */
2478 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2479 }
2480 EXPORT_SYMBOL(skb_set_owner_w);
2481 
2482 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2483 {
2484 #ifdef CONFIG_TLS_DEVICE
2485 	/* Drivers depend on in-order delivery for crypto offload,
2486 	 * partial orphan breaks out-of-order-OK logic.
2487 	 */
2488 	if (skb->decrypted)
2489 		return false;
2490 #endif
2491 	return (skb->destructor == sock_wfree ||
2492 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2493 }
2494 
2495 /* This helper is used by netem, as it can hold packets in its
2496  * delay queue. We want to allow the owner socket to send more
2497  * packets, as if they were already TX completed by a typical driver.
2498  * But we also want to keep skb->sk set because some packet schedulers
2499  * rely on it (sch_fq for example).
2500  */
2501 void skb_orphan_partial(struct sk_buff *skb)
2502 {
2503 	if (skb_is_tcp_pure_ack(skb))
2504 		return;
2505 
2506 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2507 		return;
2508 
2509 	skb_orphan(skb);
2510 }
2511 EXPORT_SYMBOL(skb_orphan_partial);
2512 
2513 /*
2514  * Read buffer destructor automatically called from kfree_skb.
2515  */
2516 void sock_rfree(struct sk_buff *skb)
2517 {
2518 	struct sock *sk = skb->sk;
2519 	unsigned int len = skb->truesize;
2520 
2521 	atomic_sub(len, &sk->sk_rmem_alloc);
2522 	sk_mem_uncharge(sk, len);
2523 }
2524 EXPORT_SYMBOL(sock_rfree);
2525 
2526 /*
2527  * Buffer destructor for skbs that are not used directly in read or write
2528  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2529  */
2530 void sock_efree(struct sk_buff *skb)
2531 {
2532 	sock_put(skb->sk);
2533 }
2534 EXPORT_SYMBOL(sock_efree);
2535 
2536 /* Buffer destructor for prefetch/receive path where reference count may
2537  * not be held, e.g. for listen sockets.
2538  */
2539 #ifdef CONFIG_INET
2540 void sock_pfree(struct sk_buff *skb)
2541 {
2542 	if (sk_is_refcounted(skb->sk))
2543 		sock_gen_put(skb->sk);
2544 }
2545 EXPORT_SYMBOL(sock_pfree);
2546 #endif /* CONFIG_INET */
2547 
2548 kuid_t sock_i_uid(struct sock *sk)
2549 {
2550 	kuid_t uid;
2551 
2552 	read_lock_bh(&sk->sk_callback_lock);
2553 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2554 	read_unlock_bh(&sk->sk_callback_lock);
2555 	return uid;
2556 }
2557 EXPORT_SYMBOL(sock_i_uid);
2558 
2559 unsigned long sock_i_ino(struct sock *sk)
2560 {
2561 	unsigned long ino;
2562 
2563 	read_lock_bh(&sk->sk_callback_lock);
2564 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2565 	read_unlock_bh(&sk->sk_callback_lock);
2566 	return ino;
2567 }
2568 EXPORT_SYMBOL(sock_i_ino);
2569 
2570 /*
2571  * Allocate a skb from the socket's send buffer.
2572  */
2573 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2574 			     gfp_t priority)
2575 {
2576 	if (force ||
2577 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2578 		struct sk_buff *skb = alloc_skb(size, priority);
2579 
2580 		if (skb) {
2581 			skb_set_owner_w(skb, sk);
2582 			return skb;
2583 		}
2584 	}
2585 	return NULL;
2586 }
2587 EXPORT_SYMBOL(sock_wmalloc);
2588 
2589 static void sock_ofree(struct sk_buff *skb)
2590 {
2591 	struct sock *sk = skb->sk;
2592 
2593 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2594 }
2595 
2596 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2597 			     gfp_t priority)
2598 {
2599 	struct sk_buff *skb;
2600 
2601 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2602 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2603 	    READ_ONCE(sysctl_optmem_max))
2604 		return NULL;
2605 
2606 	skb = alloc_skb(size, priority);
2607 	if (!skb)
2608 		return NULL;
2609 
2610 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2611 	skb->sk = sk;
2612 	skb->destructor = sock_ofree;
2613 	return skb;
2614 }
2615 
2616 /*
2617  * Allocate a memory block from the socket's option memory buffer.
2618  */
2619 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2620 {
2621 	int optmem_max = READ_ONCE(sysctl_optmem_max);
2622 
2623 	if ((unsigned int)size <= optmem_max &&
2624 	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2625 		void *mem;
2626 		/* First do the add, to avoid the race if kmalloc
2627 		 * might sleep.
2628 		 */
2629 		atomic_add(size, &sk->sk_omem_alloc);
2630 		mem = kmalloc(size, priority);
2631 		if (mem)
2632 			return mem;
2633 		atomic_sub(size, &sk->sk_omem_alloc);
2634 	}
2635 	return NULL;
2636 }
2637 EXPORT_SYMBOL(sock_kmalloc);
2638 
2639 /* Free an option memory block. Note, we actually want the inline
2640  * here as this allows gcc to detect the nullify and fold away the
2641  * condition entirely.
2642  */
2643 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2644 				  const bool nullify)
2645 {
2646 	if (WARN_ON_ONCE(!mem))
2647 		return;
2648 	if (nullify)
2649 		kfree_sensitive(mem);
2650 	else
2651 		kfree(mem);
2652 	atomic_sub(size, &sk->sk_omem_alloc);
2653 }
2654 
2655 void sock_kfree_s(struct sock *sk, void *mem, int size)
2656 {
2657 	__sock_kfree_s(sk, mem, size, false);
2658 }
2659 EXPORT_SYMBOL(sock_kfree_s);
2660 
2661 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2662 {
2663 	__sock_kfree_s(sk, mem, size, true);
2664 }
2665 EXPORT_SYMBOL(sock_kzfree_s);
2666 
2667 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2668    I think, these locks should be removed for datagram sockets.
2669  */
2670 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2671 {
2672 	DEFINE_WAIT(wait);
2673 
2674 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2675 	for (;;) {
2676 		if (!timeo)
2677 			break;
2678 		if (signal_pending(current))
2679 			break;
2680 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2681 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2682 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2683 			break;
2684 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2685 			break;
2686 		if (sk->sk_err)
2687 			break;
2688 		timeo = schedule_timeout(timeo);
2689 	}
2690 	finish_wait(sk_sleep(sk), &wait);
2691 	return timeo;
2692 }
2693 
2694 
2695 /*
2696  *	Generic send/receive buffer handlers
2697  */
2698 
2699 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2700 				     unsigned long data_len, int noblock,
2701 				     int *errcode, int max_page_order)
2702 {
2703 	struct sk_buff *skb;
2704 	long timeo;
2705 	int err;
2706 
2707 	timeo = sock_sndtimeo(sk, noblock);
2708 	for (;;) {
2709 		err = sock_error(sk);
2710 		if (err != 0)
2711 			goto failure;
2712 
2713 		err = -EPIPE;
2714 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2715 			goto failure;
2716 
2717 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2718 			break;
2719 
2720 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2721 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2722 		err = -EAGAIN;
2723 		if (!timeo)
2724 			goto failure;
2725 		if (signal_pending(current))
2726 			goto interrupted;
2727 		timeo = sock_wait_for_wmem(sk, timeo);
2728 	}
2729 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2730 				   errcode, sk->sk_allocation);
2731 	if (skb)
2732 		skb_set_owner_w(skb, sk);
2733 	return skb;
2734 
2735 interrupted:
2736 	err = sock_intr_errno(timeo);
2737 failure:
2738 	*errcode = err;
2739 	return NULL;
2740 }
2741 EXPORT_SYMBOL(sock_alloc_send_pskb);
2742 
2743 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2744 		     struct sockcm_cookie *sockc)
2745 {
2746 	u32 tsflags;
2747 
2748 	switch (cmsg->cmsg_type) {
2749 	case SO_MARK:
2750 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2751 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2752 			return -EPERM;
2753 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2754 			return -EINVAL;
2755 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2756 		break;
2757 	case SO_TIMESTAMPING_OLD:
2758 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2759 			return -EINVAL;
2760 
2761 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2762 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2763 			return -EINVAL;
2764 
2765 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2766 		sockc->tsflags |= tsflags;
2767 		break;
2768 	case SCM_TXTIME:
2769 		if (!sock_flag(sk, SOCK_TXTIME))
2770 			return -EINVAL;
2771 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2772 			return -EINVAL;
2773 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2774 		break;
2775 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2776 	case SCM_RIGHTS:
2777 	case SCM_CREDENTIALS:
2778 		break;
2779 	default:
2780 		return -EINVAL;
2781 	}
2782 	return 0;
2783 }
2784 EXPORT_SYMBOL(__sock_cmsg_send);
2785 
2786 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2787 		   struct sockcm_cookie *sockc)
2788 {
2789 	struct cmsghdr *cmsg;
2790 	int ret;
2791 
2792 	for_each_cmsghdr(cmsg, msg) {
2793 		if (!CMSG_OK(msg, cmsg))
2794 			return -EINVAL;
2795 		if (cmsg->cmsg_level != SOL_SOCKET)
2796 			continue;
2797 		ret = __sock_cmsg_send(sk, cmsg, sockc);
2798 		if (ret)
2799 			return ret;
2800 	}
2801 	return 0;
2802 }
2803 EXPORT_SYMBOL(sock_cmsg_send);
2804 
2805 static void sk_enter_memory_pressure(struct sock *sk)
2806 {
2807 	if (!sk->sk_prot->enter_memory_pressure)
2808 		return;
2809 
2810 	sk->sk_prot->enter_memory_pressure(sk);
2811 }
2812 
2813 static void sk_leave_memory_pressure(struct sock *sk)
2814 {
2815 	if (sk->sk_prot->leave_memory_pressure) {
2816 		INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
2817 				     tcp_leave_memory_pressure, sk);
2818 	} else {
2819 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2820 
2821 		if (memory_pressure && READ_ONCE(*memory_pressure))
2822 			WRITE_ONCE(*memory_pressure, 0);
2823 	}
2824 }
2825 
2826 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2827 
2828 /**
2829  * skb_page_frag_refill - check that a page_frag contains enough room
2830  * @sz: minimum size of the fragment we want to get
2831  * @pfrag: pointer to page_frag
2832  * @gfp: priority for memory allocation
2833  *
2834  * Note: While this allocator tries to use high order pages, there is
2835  * no guarantee that allocations succeed. Therefore, @sz MUST be
2836  * less or equal than PAGE_SIZE.
2837  */
2838 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2839 {
2840 	if (pfrag->page) {
2841 		if (page_ref_count(pfrag->page) == 1) {
2842 			pfrag->offset = 0;
2843 			return true;
2844 		}
2845 		if (pfrag->offset + sz <= pfrag->size)
2846 			return true;
2847 		put_page(pfrag->page);
2848 	}
2849 
2850 	pfrag->offset = 0;
2851 	if (SKB_FRAG_PAGE_ORDER &&
2852 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2853 		/* Avoid direct reclaim but allow kswapd to wake */
2854 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2855 					  __GFP_COMP | __GFP_NOWARN |
2856 					  __GFP_NORETRY,
2857 					  SKB_FRAG_PAGE_ORDER);
2858 		if (likely(pfrag->page)) {
2859 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2860 			return true;
2861 		}
2862 	}
2863 	pfrag->page = alloc_page(gfp);
2864 	if (likely(pfrag->page)) {
2865 		pfrag->size = PAGE_SIZE;
2866 		return true;
2867 	}
2868 	return false;
2869 }
2870 EXPORT_SYMBOL(skb_page_frag_refill);
2871 
2872 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2873 {
2874 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2875 		return true;
2876 
2877 	sk_enter_memory_pressure(sk);
2878 	sk_stream_moderate_sndbuf(sk);
2879 	return false;
2880 }
2881 EXPORT_SYMBOL(sk_page_frag_refill);
2882 
2883 void __lock_sock(struct sock *sk)
2884 	__releases(&sk->sk_lock.slock)
2885 	__acquires(&sk->sk_lock.slock)
2886 {
2887 	DEFINE_WAIT(wait);
2888 
2889 	for (;;) {
2890 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2891 					TASK_UNINTERRUPTIBLE);
2892 		spin_unlock_bh(&sk->sk_lock.slock);
2893 		schedule();
2894 		spin_lock_bh(&sk->sk_lock.slock);
2895 		if (!sock_owned_by_user(sk))
2896 			break;
2897 	}
2898 	finish_wait(&sk->sk_lock.wq, &wait);
2899 }
2900 
2901 void __release_sock(struct sock *sk)
2902 	__releases(&sk->sk_lock.slock)
2903 	__acquires(&sk->sk_lock.slock)
2904 {
2905 	struct sk_buff *skb, *next;
2906 
2907 	while ((skb = sk->sk_backlog.head) != NULL) {
2908 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2909 
2910 		spin_unlock_bh(&sk->sk_lock.slock);
2911 
2912 		do {
2913 			next = skb->next;
2914 			prefetch(next);
2915 			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2916 			skb_mark_not_on_list(skb);
2917 			sk_backlog_rcv(sk, skb);
2918 
2919 			cond_resched();
2920 
2921 			skb = next;
2922 		} while (skb != NULL);
2923 
2924 		spin_lock_bh(&sk->sk_lock.slock);
2925 	}
2926 
2927 	/*
2928 	 * Doing the zeroing here guarantee we can not loop forever
2929 	 * while a wild producer attempts to flood us.
2930 	 */
2931 	sk->sk_backlog.len = 0;
2932 }
2933 
2934 void __sk_flush_backlog(struct sock *sk)
2935 {
2936 	spin_lock_bh(&sk->sk_lock.slock);
2937 	__release_sock(sk);
2938 	spin_unlock_bh(&sk->sk_lock.slock);
2939 }
2940 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
2941 
2942 /**
2943  * sk_wait_data - wait for data to arrive at sk_receive_queue
2944  * @sk:    sock to wait on
2945  * @timeo: for how long
2946  * @skb:   last skb seen on sk_receive_queue
2947  *
2948  * Now socket state including sk->sk_err is changed only under lock,
2949  * hence we may omit checks after joining wait queue.
2950  * We check receive queue before schedule() only as optimization;
2951  * it is very likely that release_sock() added new data.
2952  */
2953 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2954 {
2955 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2956 	int rc;
2957 
2958 	add_wait_queue(sk_sleep(sk), &wait);
2959 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2960 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2961 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2962 	remove_wait_queue(sk_sleep(sk), &wait);
2963 	return rc;
2964 }
2965 EXPORT_SYMBOL(sk_wait_data);
2966 
2967 /**
2968  *	__sk_mem_raise_allocated - increase memory_allocated
2969  *	@sk: socket
2970  *	@size: memory size to allocate
2971  *	@amt: pages to allocate
2972  *	@kind: allocation type
2973  *
2974  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2975  */
2976 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2977 {
2978 	bool memcg_charge = mem_cgroup_sockets_enabled && sk->sk_memcg;
2979 	struct proto *prot = sk->sk_prot;
2980 	bool charged = true;
2981 	long allocated;
2982 
2983 	sk_memory_allocated_add(sk, amt);
2984 	allocated = sk_memory_allocated(sk);
2985 	if (memcg_charge &&
2986 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt,
2987 						gfp_memcg_charge())))
2988 		goto suppress_allocation;
2989 
2990 	/* Under limit. */
2991 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2992 		sk_leave_memory_pressure(sk);
2993 		return 1;
2994 	}
2995 
2996 	/* Under pressure. */
2997 	if (allocated > sk_prot_mem_limits(sk, 1))
2998 		sk_enter_memory_pressure(sk);
2999 
3000 	/* Over hard limit. */
3001 	if (allocated > sk_prot_mem_limits(sk, 2))
3002 		goto suppress_allocation;
3003 
3004 	/* guarantee minimum buffer size under pressure */
3005 	if (kind == SK_MEM_RECV) {
3006 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3007 			return 1;
3008 
3009 	} else { /* SK_MEM_SEND */
3010 		int wmem0 = sk_get_wmem0(sk, prot);
3011 
3012 		if (sk->sk_type == SOCK_STREAM) {
3013 			if (sk->sk_wmem_queued < wmem0)
3014 				return 1;
3015 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3016 				return 1;
3017 		}
3018 	}
3019 
3020 	if (sk_has_memory_pressure(sk)) {
3021 		u64 alloc;
3022 
3023 		if (!sk_under_memory_pressure(sk))
3024 			return 1;
3025 		alloc = sk_sockets_allocated_read_positive(sk);
3026 		if (sk_prot_mem_limits(sk, 2) > alloc *
3027 		    sk_mem_pages(sk->sk_wmem_queued +
3028 				 atomic_read(&sk->sk_rmem_alloc) +
3029 				 sk->sk_forward_alloc))
3030 			return 1;
3031 	}
3032 
3033 suppress_allocation:
3034 
3035 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3036 		sk_stream_moderate_sndbuf(sk);
3037 
3038 		/* Fail only if socket is _under_ its sndbuf.
3039 		 * In this case we cannot block, so that we have to fail.
3040 		 */
3041 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3042 			/* Force charge with __GFP_NOFAIL */
3043 			if (memcg_charge && !charged) {
3044 				mem_cgroup_charge_skmem(sk->sk_memcg, amt,
3045 					gfp_memcg_charge() | __GFP_NOFAIL);
3046 			}
3047 			return 1;
3048 		}
3049 	}
3050 
3051 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3052 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3053 
3054 	sk_memory_allocated_sub(sk, amt);
3055 
3056 	if (memcg_charge && charged)
3057 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
3058 
3059 	return 0;
3060 }
3061 
3062 /**
3063  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3064  *	@sk: socket
3065  *	@size: memory size to allocate
3066  *	@kind: allocation type
3067  *
3068  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3069  *	rmem allocation. This function assumes that protocols which have
3070  *	memory_pressure use sk_wmem_queued as write buffer accounting.
3071  */
3072 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3073 {
3074 	int ret, amt = sk_mem_pages(size);
3075 
3076 	sk->sk_forward_alloc += amt << PAGE_SHIFT;
3077 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3078 	if (!ret)
3079 		sk->sk_forward_alloc -= amt << PAGE_SHIFT;
3080 	return ret;
3081 }
3082 EXPORT_SYMBOL(__sk_mem_schedule);
3083 
3084 /**
3085  *	__sk_mem_reduce_allocated - reclaim memory_allocated
3086  *	@sk: socket
3087  *	@amount: number of quanta
3088  *
3089  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3090  */
3091 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3092 {
3093 	sk_memory_allocated_sub(sk, amount);
3094 
3095 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3096 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3097 
3098 	if (sk_under_memory_pressure(sk) &&
3099 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3100 		sk_leave_memory_pressure(sk);
3101 }
3102 
3103 /**
3104  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3105  *	@sk: socket
3106  *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3107  */
3108 void __sk_mem_reclaim(struct sock *sk, int amount)
3109 {
3110 	amount >>= PAGE_SHIFT;
3111 	sk->sk_forward_alloc -= amount << PAGE_SHIFT;
3112 	__sk_mem_reduce_allocated(sk, amount);
3113 }
3114 EXPORT_SYMBOL(__sk_mem_reclaim);
3115 
3116 int sk_set_peek_off(struct sock *sk, int val)
3117 {
3118 	sk->sk_peek_off = val;
3119 	return 0;
3120 }
3121 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3122 
3123 /*
3124  * Set of default routines for initialising struct proto_ops when
3125  * the protocol does not support a particular function. In certain
3126  * cases where it makes no sense for a protocol to have a "do nothing"
3127  * function, some default processing is provided.
3128  */
3129 
3130 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3131 {
3132 	return -EOPNOTSUPP;
3133 }
3134 EXPORT_SYMBOL(sock_no_bind);
3135 
3136 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3137 		    int len, int flags)
3138 {
3139 	return -EOPNOTSUPP;
3140 }
3141 EXPORT_SYMBOL(sock_no_connect);
3142 
3143 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3144 {
3145 	return -EOPNOTSUPP;
3146 }
3147 EXPORT_SYMBOL(sock_no_socketpair);
3148 
3149 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3150 		   bool kern)
3151 {
3152 	return -EOPNOTSUPP;
3153 }
3154 EXPORT_SYMBOL(sock_no_accept);
3155 
3156 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3157 		    int peer)
3158 {
3159 	return -EOPNOTSUPP;
3160 }
3161 EXPORT_SYMBOL(sock_no_getname);
3162 
3163 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3164 {
3165 	return -EOPNOTSUPP;
3166 }
3167 EXPORT_SYMBOL(sock_no_ioctl);
3168 
3169 int sock_no_listen(struct socket *sock, int backlog)
3170 {
3171 	return -EOPNOTSUPP;
3172 }
3173 EXPORT_SYMBOL(sock_no_listen);
3174 
3175 int sock_no_shutdown(struct socket *sock, int how)
3176 {
3177 	return -EOPNOTSUPP;
3178 }
3179 EXPORT_SYMBOL(sock_no_shutdown);
3180 
3181 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3182 {
3183 	return -EOPNOTSUPP;
3184 }
3185 EXPORT_SYMBOL(sock_no_sendmsg);
3186 
3187 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3188 {
3189 	return -EOPNOTSUPP;
3190 }
3191 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3192 
3193 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3194 		    int flags)
3195 {
3196 	return -EOPNOTSUPP;
3197 }
3198 EXPORT_SYMBOL(sock_no_recvmsg);
3199 
3200 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3201 {
3202 	/* Mirror missing mmap method error code */
3203 	return -ENODEV;
3204 }
3205 EXPORT_SYMBOL(sock_no_mmap);
3206 
3207 /*
3208  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3209  * various sock-based usage counts.
3210  */
3211 void __receive_sock(struct file *file)
3212 {
3213 	struct socket *sock;
3214 
3215 	sock = sock_from_file(file);
3216 	if (sock) {
3217 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3218 		sock_update_classid(&sock->sk->sk_cgrp_data);
3219 	}
3220 }
3221 
3222 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
3223 {
3224 	ssize_t res;
3225 	struct msghdr msg = {.msg_flags = flags};
3226 	struct kvec iov;
3227 	char *kaddr = kmap(page);
3228 	iov.iov_base = kaddr + offset;
3229 	iov.iov_len = size;
3230 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
3231 	kunmap(page);
3232 	return res;
3233 }
3234 EXPORT_SYMBOL(sock_no_sendpage);
3235 
3236 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
3237 				int offset, size_t size, int flags)
3238 {
3239 	ssize_t res;
3240 	struct msghdr msg = {.msg_flags = flags};
3241 	struct kvec iov;
3242 	char *kaddr = kmap(page);
3243 
3244 	iov.iov_base = kaddr + offset;
3245 	iov.iov_len = size;
3246 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
3247 	kunmap(page);
3248 	return res;
3249 }
3250 EXPORT_SYMBOL(sock_no_sendpage_locked);
3251 
3252 /*
3253  *	Default Socket Callbacks
3254  */
3255 
3256 static void sock_def_wakeup(struct sock *sk)
3257 {
3258 	struct socket_wq *wq;
3259 
3260 	rcu_read_lock();
3261 	wq = rcu_dereference(sk->sk_wq);
3262 	if (skwq_has_sleeper(wq))
3263 		wake_up_interruptible_all(&wq->wait);
3264 	rcu_read_unlock();
3265 }
3266 
3267 static void sock_def_error_report(struct sock *sk)
3268 {
3269 	struct socket_wq *wq;
3270 
3271 	rcu_read_lock();
3272 	wq = rcu_dereference(sk->sk_wq);
3273 	if (skwq_has_sleeper(wq))
3274 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3275 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3276 	rcu_read_unlock();
3277 }
3278 
3279 void sock_def_readable(struct sock *sk)
3280 {
3281 	struct socket_wq *wq;
3282 
3283 	trace_sk_data_ready(sk);
3284 
3285 	rcu_read_lock();
3286 	wq = rcu_dereference(sk->sk_wq);
3287 	if (skwq_has_sleeper(wq))
3288 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3289 						EPOLLRDNORM | EPOLLRDBAND);
3290 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3291 	rcu_read_unlock();
3292 }
3293 
3294 static void sock_def_write_space(struct sock *sk)
3295 {
3296 	struct socket_wq *wq;
3297 
3298 	rcu_read_lock();
3299 
3300 	/* Do not wake up a writer until he can make "significant"
3301 	 * progress.  --DaveM
3302 	 */
3303 	if (sock_writeable(sk)) {
3304 		wq = rcu_dereference(sk->sk_wq);
3305 		if (skwq_has_sleeper(wq))
3306 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3307 						EPOLLWRNORM | EPOLLWRBAND);
3308 
3309 		/* Should agree with poll, otherwise some programs break */
3310 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3311 	}
3312 
3313 	rcu_read_unlock();
3314 }
3315 
3316 /* An optimised version of sock_def_write_space(), should only be called
3317  * for SOCK_RCU_FREE sockets under RCU read section and after putting
3318  * ->sk_wmem_alloc.
3319  */
3320 static void sock_def_write_space_wfree(struct sock *sk)
3321 {
3322 	/* Do not wake up a writer until he can make "significant"
3323 	 * progress.  --DaveM
3324 	 */
3325 	if (sock_writeable(sk)) {
3326 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3327 
3328 		/* rely on refcount_sub from sock_wfree() */
3329 		smp_mb__after_atomic();
3330 		if (wq && waitqueue_active(&wq->wait))
3331 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3332 						EPOLLWRNORM | EPOLLWRBAND);
3333 
3334 		/* Should agree with poll, otherwise some programs break */
3335 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3336 	}
3337 }
3338 
3339 static void sock_def_destruct(struct sock *sk)
3340 {
3341 }
3342 
3343 void sk_send_sigurg(struct sock *sk)
3344 {
3345 	if (sk->sk_socket && sk->sk_socket->file)
3346 		if (send_sigurg(&sk->sk_socket->file->f_owner))
3347 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3348 }
3349 EXPORT_SYMBOL(sk_send_sigurg);
3350 
3351 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3352 		    unsigned long expires)
3353 {
3354 	if (!mod_timer(timer, expires))
3355 		sock_hold(sk);
3356 }
3357 EXPORT_SYMBOL(sk_reset_timer);
3358 
3359 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3360 {
3361 	if (del_timer(timer))
3362 		__sock_put(sk);
3363 }
3364 EXPORT_SYMBOL(sk_stop_timer);
3365 
3366 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3367 {
3368 	if (del_timer_sync(timer))
3369 		__sock_put(sk);
3370 }
3371 EXPORT_SYMBOL(sk_stop_timer_sync);
3372 
3373 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3374 {
3375 	sk_init_common(sk);
3376 	sk->sk_send_head	=	NULL;
3377 
3378 	timer_setup(&sk->sk_timer, NULL, 0);
3379 
3380 	sk->sk_allocation	=	GFP_KERNEL;
3381 	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3382 	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3383 	sk->sk_state		=	TCP_CLOSE;
3384 	sk->sk_use_task_frag	=	true;
3385 	sk_set_socket(sk, sock);
3386 
3387 	sock_set_flag(sk, SOCK_ZAPPED);
3388 
3389 	if (sock) {
3390 		sk->sk_type	=	sock->type;
3391 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3392 		sock->sk	=	sk;
3393 	} else {
3394 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3395 	}
3396 	sk->sk_uid	=	uid;
3397 
3398 	rwlock_init(&sk->sk_callback_lock);
3399 	if (sk->sk_kern_sock)
3400 		lockdep_set_class_and_name(
3401 			&sk->sk_callback_lock,
3402 			af_kern_callback_keys + sk->sk_family,
3403 			af_family_kern_clock_key_strings[sk->sk_family]);
3404 	else
3405 		lockdep_set_class_and_name(
3406 			&sk->sk_callback_lock,
3407 			af_callback_keys + sk->sk_family,
3408 			af_family_clock_key_strings[sk->sk_family]);
3409 
3410 	sk->sk_state_change	=	sock_def_wakeup;
3411 	sk->sk_data_ready	=	sock_def_readable;
3412 	sk->sk_write_space	=	sock_def_write_space;
3413 	sk->sk_error_report	=	sock_def_error_report;
3414 	sk->sk_destruct		=	sock_def_destruct;
3415 
3416 	sk->sk_frag.page	=	NULL;
3417 	sk->sk_frag.offset	=	0;
3418 	sk->sk_peek_off		=	-1;
3419 
3420 	sk->sk_peer_pid 	=	NULL;
3421 	sk->sk_peer_cred	=	NULL;
3422 	spin_lock_init(&sk->sk_peer_lock);
3423 
3424 	sk->sk_write_pending	=	0;
3425 	sk->sk_rcvlowat		=	1;
3426 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3427 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3428 
3429 	sk->sk_stamp = SK_DEFAULT_STAMP;
3430 #if BITS_PER_LONG==32
3431 	seqlock_init(&sk->sk_stamp_seq);
3432 #endif
3433 	atomic_set(&sk->sk_zckey, 0);
3434 
3435 #ifdef CONFIG_NET_RX_BUSY_POLL
3436 	sk->sk_napi_id		=	0;
3437 	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3438 #endif
3439 
3440 	sk->sk_max_pacing_rate = ~0UL;
3441 	sk->sk_pacing_rate = ~0UL;
3442 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3443 	sk->sk_incoming_cpu = -1;
3444 
3445 	sk_rx_queue_clear(sk);
3446 	/*
3447 	 * Before updating sk_refcnt, we must commit prior changes to memory
3448 	 * (Documentation/RCU/rculist_nulls.rst for details)
3449 	 */
3450 	smp_wmb();
3451 	refcount_set(&sk->sk_refcnt, 1);
3452 	atomic_set(&sk->sk_drops, 0);
3453 }
3454 EXPORT_SYMBOL(sock_init_data_uid);
3455 
3456 void sock_init_data(struct socket *sock, struct sock *sk)
3457 {
3458 	kuid_t uid = sock ?
3459 		SOCK_INODE(sock)->i_uid :
3460 		make_kuid(sock_net(sk)->user_ns, 0);
3461 
3462 	sock_init_data_uid(sock, sk, uid);
3463 }
3464 EXPORT_SYMBOL(sock_init_data);
3465 
3466 void lock_sock_nested(struct sock *sk, int subclass)
3467 {
3468 	/* The sk_lock has mutex_lock() semantics here. */
3469 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3470 
3471 	might_sleep();
3472 	spin_lock_bh(&sk->sk_lock.slock);
3473 	if (sock_owned_by_user_nocheck(sk))
3474 		__lock_sock(sk);
3475 	sk->sk_lock.owned = 1;
3476 	spin_unlock_bh(&sk->sk_lock.slock);
3477 }
3478 EXPORT_SYMBOL(lock_sock_nested);
3479 
3480 void release_sock(struct sock *sk)
3481 {
3482 	spin_lock_bh(&sk->sk_lock.slock);
3483 	if (sk->sk_backlog.tail)
3484 		__release_sock(sk);
3485 
3486 	/* Warning : release_cb() might need to release sk ownership,
3487 	 * ie call sock_release_ownership(sk) before us.
3488 	 */
3489 	if (sk->sk_prot->release_cb)
3490 		sk->sk_prot->release_cb(sk);
3491 
3492 	sock_release_ownership(sk);
3493 	if (waitqueue_active(&sk->sk_lock.wq))
3494 		wake_up(&sk->sk_lock.wq);
3495 	spin_unlock_bh(&sk->sk_lock.slock);
3496 }
3497 EXPORT_SYMBOL(release_sock);
3498 
3499 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3500 {
3501 	might_sleep();
3502 	spin_lock_bh(&sk->sk_lock.slock);
3503 
3504 	if (!sock_owned_by_user_nocheck(sk)) {
3505 		/*
3506 		 * Fast path return with bottom halves disabled and
3507 		 * sock::sk_lock.slock held.
3508 		 *
3509 		 * The 'mutex' is not contended and holding
3510 		 * sock::sk_lock.slock prevents all other lockers to
3511 		 * proceed so the corresponding unlock_sock_fast() can
3512 		 * avoid the slow path of release_sock() completely and
3513 		 * just release slock.
3514 		 *
3515 		 * From a semantical POV this is equivalent to 'acquiring'
3516 		 * the 'mutex', hence the corresponding lockdep
3517 		 * mutex_release() has to happen in the fast path of
3518 		 * unlock_sock_fast().
3519 		 */
3520 		return false;
3521 	}
3522 
3523 	__lock_sock(sk);
3524 	sk->sk_lock.owned = 1;
3525 	__acquire(&sk->sk_lock.slock);
3526 	spin_unlock_bh(&sk->sk_lock.slock);
3527 	return true;
3528 }
3529 EXPORT_SYMBOL(__lock_sock_fast);
3530 
3531 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3532 		   bool timeval, bool time32)
3533 {
3534 	struct sock *sk = sock->sk;
3535 	struct timespec64 ts;
3536 
3537 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3538 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3539 	if (ts.tv_sec == -1)
3540 		return -ENOENT;
3541 	if (ts.tv_sec == 0) {
3542 		ktime_t kt = ktime_get_real();
3543 		sock_write_timestamp(sk, kt);
3544 		ts = ktime_to_timespec64(kt);
3545 	}
3546 
3547 	if (timeval)
3548 		ts.tv_nsec /= 1000;
3549 
3550 #ifdef CONFIG_COMPAT_32BIT_TIME
3551 	if (time32)
3552 		return put_old_timespec32(&ts, userstamp);
3553 #endif
3554 #ifdef CONFIG_SPARC64
3555 	/* beware of padding in sparc64 timeval */
3556 	if (timeval && !in_compat_syscall()) {
3557 		struct __kernel_old_timeval __user tv = {
3558 			.tv_sec = ts.tv_sec,
3559 			.tv_usec = ts.tv_nsec,
3560 		};
3561 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3562 			return -EFAULT;
3563 		return 0;
3564 	}
3565 #endif
3566 	return put_timespec64(&ts, userstamp);
3567 }
3568 EXPORT_SYMBOL(sock_gettstamp);
3569 
3570 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3571 {
3572 	if (!sock_flag(sk, flag)) {
3573 		unsigned long previous_flags = sk->sk_flags;
3574 
3575 		sock_set_flag(sk, flag);
3576 		/*
3577 		 * we just set one of the two flags which require net
3578 		 * time stamping, but time stamping might have been on
3579 		 * already because of the other one
3580 		 */
3581 		if (sock_needs_netstamp(sk) &&
3582 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3583 			net_enable_timestamp();
3584 	}
3585 }
3586 
3587 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3588 		       int level, int type)
3589 {
3590 	struct sock_exterr_skb *serr;
3591 	struct sk_buff *skb;
3592 	int copied, err;
3593 
3594 	err = -EAGAIN;
3595 	skb = sock_dequeue_err_skb(sk);
3596 	if (skb == NULL)
3597 		goto out;
3598 
3599 	copied = skb->len;
3600 	if (copied > len) {
3601 		msg->msg_flags |= MSG_TRUNC;
3602 		copied = len;
3603 	}
3604 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3605 	if (err)
3606 		goto out_free_skb;
3607 
3608 	sock_recv_timestamp(msg, sk, skb);
3609 
3610 	serr = SKB_EXT_ERR(skb);
3611 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3612 
3613 	msg->msg_flags |= MSG_ERRQUEUE;
3614 	err = copied;
3615 
3616 out_free_skb:
3617 	kfree_skb(skb);
3618 out:
3619 	return err;
3620 }
3621 EXPORT_SYMBOL(sock_recv_errqueue);
3622 
3623 /*
3624  *	Get a socket option on an socket.
3625  *
3626  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3627  *	asynchronous errors should be reported by getsockopt. We assume
3628  *	this means if you specify SO_ERROR (otherwise whats the point of it).
3629  */
3630 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3631 			   char __user *optval, int __user *optlen)
3632 {
3633 	struct sock *sk = sock->sk;
3634 
3635 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3636 	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3637 }
3638 EXPORT_SYMBOL(sock_common_getsockopt);
3639 
3640 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3641 			int flags)
3642 {
3643 	struct sock *sk = sock->sk;
3644 	int addr_len = 0;
3645 	int err;
3646 
3647 	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3648 	if (err >= 0)
3649 		msg->msg_namelen = addr_len;
3650 	return err;
3651 }
3652 EXPORT_SYMBOL(sock_common_recvmsg);
3653 
3654 /*
3655  *	Set socket options on an inet socket.
3656  */
3657 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3658 			   sockptr_t optval, unsigned int optlen)
3659 {
3660 	struct sock *sk = sock->sk;
3661 
3662 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3663 	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3664 }
3665 EXPORT_SYMBOL(sock_common_setsockopt);
3666 
3667 void sk_common_release(struct sock *sk)
3668 {
3669 	if (sk->sk_prot->destroy)
3670 		sk->sk_prot->destroy(sk);
3671 
3672 	/*
3673 	 * Observation: when sk_common_release is called, processes have
3674 	 * no access to socket. But net still has.
3675 	 * Step one, detach it from networking:
3676 	 *
3677 	 * A. Remove from hash tables.
3678 	 */
3679 
3680 	sk->sk_prot->unhash(sk);
3681 
3682 	/*
3683 	 * In this point socket cannot receive new packets, but it is possible
3684 	 * that some packets are in flight because some CPU runs receiver and
3685 	 * did hash table lookup before we unhashed socket. They will achieve
3686 	 * receive queue and will be purged by socket destructor.
3687 	 *
3688 	 * Also we still have packets pending on receive queue and probably,
3689 	 * our own packets waiting in device queues. sock_destroy will drain
3690 	 * receive queue, but transmitted packets will delay socket destruction
3691 	 * until the last reference will be released.
3692 	 */
3693 
3694 	sock_orphan(sk);
3695 
3696 	xfrm_sk_free_policy(sk);
3697 
3698 	sock_put(sk);
3699 }
3700 EXPORT_SYMBOL(sk_common_release);
3701 
3702 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3703 {
3704 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3705 
3706 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3707 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3708 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3709 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3710 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3711 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3712 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3713 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3714 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3715 }
3716 
3717 #ifdef CONFIG_PROC_FS
3718 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3719 
3720 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3721 {
3722 	int cpu, idx = prot->inuse_idx;
3723 	int res = 0;
3724 
3725 	for_each_possible_cpu(cpu)
3726 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3727 
3728 	return res >= 0 ? res : 0;
3729 }
3730 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3731 
3732 int sock_inuse_get(struct net *net)
3733 {
3734 	int cpu, res = 0;
3735 
3736 	for_each_possible_cpu(cpu)
3737 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3738 
3739 	return res;
3740 }
3741 
3742 EXPORT_SYMBOL_GPL(sock_inuse_get);
3743 
3744 static int __net_init sock_inuse_init_net(struct net *net)
3745 {
3746 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3747 	if (net->core.prot_inuse == NULL)
3748 		return -ENOMEM;
3749 	return 0;
3750 }
3751 
3752 static void __net_exit sock_inuse_exit_net(struct net *net)
3753 {
3754 	free_percpu(net->core.prot_inuse);
3755 }
3756 
3757 static struct pernet_operations net_inuse_ops = {
3758 	.init = sock_inuse_init_net,
3759 	.exit = sock_inuse_exit_net,
3760 };
3761 
3762 static __init int net_inuse_init(void)
3763 {
3764 	if (register_pernet_subsys(&net_inuse_ops))
3765 		panic("Cannot initialize net inuse counters");
3766 
3767 	return 0;
3768 }
3769 
3770 core_initcall(net_inuse_init);
3771 
3772 static int assign_proto_idx(struct proto *prot)
3773 {
3774 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3775 
3776 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3777 		pr_err("PROTO_INUSE_NR exhausted\n");
3778 		return -ENOSPC;
3779 	}
3780 
3781 	set_bit(prot->inuse_idx, proto_inuse_idx);
3782 	return 0;
3783 }
3784 
3785 static void release_proto_idx(struct proto *prot)
3786 {
3787 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3788 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3789 }
3790 #else
3791 static inline int assign_proto_idx(struct proto *prot)
3792 {
3793 	return 0;
3794 }
3795 
3796 static inline void release_proto_idx(struct proto *prot)
3797 {
3798 }
3799 
3800 #endif
3801 
3802 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3803 {
3804 	if (!twsk_prot)
3805 		return;
3806 	kfree(twsk_prot->twsk_slab_name);
3807 	twsk_prot->twsk_slab_name = NULL;
3808 	kmem_cache_destroy(twsk_prot->twsk_slab);
3809 	twsk_prot->twsk_slab = NULL;
3810 }
3811 
3812 static int tw_prot_init(const struct proto *prot)
3813 {
3814 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3815 
3816 	if (!twsk_prot)
3817 		return 0;
3818 
3819 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3820 					      prot->name);
3821 	if (!twsk_prot->twsk_slab_name)
3822 		return -ENOMEM;
3823 
3824 	twsk_prot->twsk_slab =
3825 		kmem_cache_create(twsk_prot->twsk_slab_name,
3826 				  twsk_prot->twsk_obj_size, 0,
3827 				  SLAB_ACCOUNT | prot->slab_flags,
3828 				  NULL);
3829 	if (!twsk_prot->twsk_slab) {
3830 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3831 			prot->name);
3832 		return -ENOMEM;
3833 	}
3834 
3835 	return 0;
3836 }
3837 
3838 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3839 {
3840 	if (!rsk_prot)
3841 		return;
3842 	kfree(rsk_prot->slab_name);
3843 	rsk_prot->slab_name = NULL;
3844 	kmem_cache_destroy(rsk_prot->slab);
3845 	rsk_prot->slab = NULL;
3846 }
3847 
3848 static int req_prot_init(const struct proto *prot)
3849 {
3850 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3851 
3852 	if (!rsk_prot)
3853 		return 0;
3854 
3855 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3856 					prot->name);
3857 	if (!rsk_prot->slab_name)
3858 		return -ENOMEM;
3859 
3860 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3861 					   rsk_prot->obj_size, 0,
3862 					   SLAB_ACCOUNT | prot->slab_flags,
3863 					   NULL);
3864 
3865 	if (!rsk_prot->slab) {
3866 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3867 			prot->name);
3868 		return -ENOMEM;
3869 	}
3870 	return 0;
3871 }
3872 
3873 int proto_register(struct proto *prot, int alloc_slab)
3874 {
3875 	int ret = -ENOBUFS;
3876 
3877 	if (prot->memory_allocated && !prot->sysctl_mem) {
3878 		pr_err("%s: missing sysctl_mem\n", prot->name);
3879 		return -EINVAL;
3880 	}
3881 	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
3882 		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
3883 		return -EINVAL;
3884 	}
3885 	if (alloc_slab) {
3886 		prot->slab = kmem_cache_create_usercopy(prot->name,
3887 					prot->obj_size, 0,
3888 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3889 					prot->slab_flags,
3890 					prot->useroffset, prot->usersize,
3891 					NULL);
3892 
3893 		if (prot->slab == NULL) {
3894 			pr_crit("%s: Can't create sock SLAB cache!\n",
3895 				prot->name);
3896 			goto out;
3897 		}
3898 
3899 		if (req_prot_init(prot))
3900 			goto out_free_request_sock_slab;
3901 
3902 		if (tw_prot_init(prot))
3903 			goto out_free_timewait_sock_slab;
3904 	}
3905 
3906 	mutex_lock(&proto_list_mutex);
3907 	ret = assign_proto_idx(prot);
3908 	if (ret) {
3909 		mutex_unlock(&proto_list_mutex);
3910 		goto out_free_timewait_sock_slab;
3911 	}
3912 	list_add(&prot->node, &proto_list);
3913 	mutex_unlock(&proto_list_mutex);
3914 	return ret;
3915 
3916 out_free_timewait_sock_slab:
3917 	if (alloc_slab)
3918 		tw_prot_cleanup(prot->twsk_prot);
3919 out_free_request_sock_slab:
3920 	if (alloc_slab) {
3921 		req_prot_cleanup(prot->rsk_prot);
3922 
3923 		kmem_cache_destroy(prot->slab);
3924 		prot->slab = NULL;
3925 	}
3926 out:
3927 	return ret;
3928 }
3929 EXPORT_SYMBOL(proto_register);
3930 
3931 void proto_unregister(struct proto *prot)
3932 {
3933 	mutex_lock(&proto_list_mutex);
3934 	release_proto_idx(prot);
3935 	list_del(&prot->node);
3936 	mutex_unlock(&proto_list_mutex);
3937 
3938 	kmem_cache_destroy(prot->slab);
3939 	prot->slab = NULL;
3940 
3941 	req_prot_cleanup(prot->rsk_prot);
3942 	tw_prot_cleanup(prot->twsk_prot);
3943 }
3944 EXPORT_SYMBOL(proto_unregister);
3945 
3946 int sock_load_diag_module(int family, int protocol)
3947 {
3948 	if (!protocol) {
3949 		if (!sock_is_registered(family))
3950 			return -ENOENT;
3951 
3952 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3953 				      NETLINK_SOCK_DIAG, family);
3954 	}
3955 
3956 #ifdef CONFIG_INET
3957 	if (family == AF_INET &&
3958 	    protocol != IPPROTO_RAW &&
3959 	    protocol < MAX_INET_PROTOS &&
3960 	    !rcu_access_pointer(inet_protos[protocol]))
3961 		return -ENOENT;
3962 #endif
3963 
3964 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3965 			      NETLINK_SOCK_DIAG, family, protocol);
3966 }
3967 EXPORT_SYMBOL(sock_load_diag_module);
3968 
3969 #ifdef CONFIG_PROC_FS
3970 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3971 	__acquires(proto_list_mutex)
3972 {
3973 	mutex_lock(&proto_list_mutex);
3974 	return seq_list_start_head(&proto_list, *pos);
3975 }
3976 
3977 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3978 {
3979 	return seq_list_next(v, &proto_list, pos);
3980 }
3981 
3982 static void proto_seq_stop(struct seq_file *seq, void *v)
3983 	__releases(proto_list_mutex)
3984 {
3985 	mutex_unlock(&proto_list_mutex);
3986 }
3987 
3988 static char proto_method_implemented(const void *method)
3989 {
3990 	return method == NULL ? 'n' : 'y';
3991 }
3992 static long sock_prot_memory_allocated(struct proto *proto)
3993 {
3994 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3995 }
3996 
3997 static const char *sock_prot_memory_pressure(struct proto *proto)
3998 {
3999 	return proto->memory_pressure != NULL ?
4000 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4001 }
4002 
4003 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4004 {
4005 
4006 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4007 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4008 		   proto->name,
4009 		   proto->obj_size,
4010 		   sock_prot_inuse_get(seq_file_net(seq), proto),
4011 		   sock_prot_memory_allocated(proto),
4012 		   sock_prot_memory_pressure(proto),
4013 		   proto->max_header,
4014 		   proto->slab == NULL ? "no" : "yes",
4015 		   module_name(proto->owner),
4016 		   proto_method_implemented(proto->close),
4017 		   proto_method_implemented(proto->connect),
4018 		   proto_method_implemented(proto->disconnect),
4019 		   proto_method_implemented(proto->accept),
4020 		   proto_method_implemented(proto->ioctl),
4021 		   proto_method_implemented(proto->init),
4022 		   proto_method_implemented(proto->destroy),
4023 		   proto_method_implemented(proto->shutdown),
4024 		   proto_method_implemented(proto->setsockopt),
4025 		   proto_method_implemented(proto->getsockopt),
4026 		   proto_method_implemented(proto->sendmsg),
4027 		   proto_method_implemented(proto->recvmsg),
4028 		   proto_method_implemented(proto->sendpage),
4029 		   proto_method_implemented(proto->bind),
4030 		   proto_method_implemented(proto->backlog_rcv),
4031 		   proto_method_implemented(proto->hash),
4032 		   proto_method_implemented(proto->unhash),
4033 		   proto_method_implemented(proto->get_port),
4034 		   proto_method_implemented(proto->enter_memory_pressure));
4035 }
4036 
4037 static int proto_seq_show(struct seq_file *seq, void *v)
4038 {
4039 	if (v == &proto_list)
4040 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4041 			   "protocol",
4042 			   "size",
4043 			   "sockets",
4044 			   "memory",
4045 			   "press",
4046 			   "maxhdr",
4047 			   "slab",
4048 			   "module",
4049 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
4050 	else
4051 		proto_seq_printf(seq, list_entry(v, struct proto, node));
4052 	return 0;
4053 }
4054 
4055 static const struct seq_operations proto_seq_ops = {
4056 	.start  = proto_seq_start,
4057 	.next   = proto_seq_next,
4058 	.stop   = proto_seq_stop,
4059 	.show   = proto_seq_show,
4060 };
4061 
4062 static __net_init int proto_init_net(struct net *net)
4063 {
4064 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4065 			sizeof(struct seq_net_private)))
4066 		return -ENOMEM;
4067 
4068 	return 0;
4069 }
4070 
4071 static __net_exit void proto_exit_net(struct net *net)
4072 {
4073 	remove_proc_entry("protocols", net->proc_net);
4074 }
4075 
4076 
4077 static __net_initdata struct pernet_operations proto_net_ops = {
4078 	.init = proto_init_net,
4079 	.exit = proto_exit_net,
4080 };
4081 
4082 static int __init proto_init(void)
4083 {
4084 	return register_pernet_subsys(&proto_net_ops);
4085 }
4086 
4087 subsys_initcall(proto_init);
4088 
4089 #endif /* PROC_FS */
4090 
4091 #ifdef CONFIG_NET_RX_BUSY_POLL
4092 bool sk_busy_loop_end(void *p, unsigned long start_time)
4093 {
4094 	struct sock *sk = p;
4095 
4096 	return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
4097 	       sk_busy_loop_timeout(sk, start_time);
4098 }
4099 EXPORT_SYMBOL(sk_busy_loop_end);
4100 #endif /* CONFIG_NET_RX_BUSY_POLL */
4101 
4102 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4103 {
4104 	if (!sk->sk_prot->bind_add)
4105 		return -EOPNOTSUPP;
4106 	return sk->sk_prot->bind_add(sk, addr, addr_len);
4107 }
4108 EXPORT_SYMBOL(sock_bind_add);
4109