xref: /linux/net/core/sock.c (revision 39f75da7bcc829ddc4d40bb60d0e95520de7898b)
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 static DEFINE_MUTEX(proto_list_mutex);
145 static LIST_HEAD(proto_list);
146 
147 static void sock_inuse_add(struct net *net, int val);
148 
149 /**
150  * sk_ns_capable - General socket capability test
151  * @sk: Socket to use a capability on or through
152  * @user_ns: The user namespace of the capability to use
153  * @cap: The capability to use
154  *
155  * Test to see if the opener of the socket had when the socket was
156  * created and the current process has the capability @cap in the user
157  * namespace @user_ns.
158  */
159 bool sk_ns_capable(const struct sock *sk,
160 		   struct user_namespace *user_ns, int cap)
161 {
162 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
163 		ns_capable(user_ns, cap);
164 }
165 EXPORT_SYMBOL(sk_ns_capable);
166 
167 /**
168  * sk_capable - Socket global capability test
169  * @sk: Socket to use a capability on or through
170  * @cap: The global capability to use
171  *
172  * Test to see if the opener of the socket had when the socket was
173  * created and the current process has the capability @cap in all user
174  * namespaces.
175  */
176 bool sk_capable(const struct sock *sk, int cap)
177 {
178 	return sk_ns_capable(sk, &init_user_ns, cap);
179 }
180 EXPORT_SYMBOL(sk_capable);
181 
182 /**
183  * sk_net_capable - Network namespace socket capability test
184  * @sk: Socket to use a capability on or through
185  * @cap: The capability to use
186  *
187  * Test to see if the opener of the socket had when the socket was created
188  * and the current process has the capability @cap over the network namespace
189  * the socket is a member of.
190  */
191 bool sk_net_capable(const struct sock *sk, int cap)
192 {
193 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
194 }
195 EXPORT_SYMBOL(sk_net_capable);
196 
197 /*
198  * Each address family might have different locking rules, so we have
199  * one slock key per address family and separate keys for internal and
200  * userspace sockets.
201  */
202 static struct lock_class_key af_family_keys[AF_MAX];
203 static struct lock_class_key af_family_kern_keys[AF_MAX];
204 static struct lock_class_key af_family_slock_keys[AF_MAX];
205 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
206 
207 /*
208  * Make lock validator output more readable. (we pre-construct these
209  * strings build-time, so that runtime initialization of socket
210  * locks is fast):
211  */
212 
213 #define _sock_locks(x)						  \
214   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
215   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
216   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
217   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
218   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
219   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
220   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
221   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
222   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
223   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
224   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
225   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
226   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
227   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
228   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
229   x "AF_MAX"
230 
231 static const char *const af_family_key_strings[AF_MAX+1] = {
232 	_sock_locks("sk_lock-")
233 };
234 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
235 	_sock_locks("slock-")
236 };
237 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
238 	_sock_locks("clock-")
239 };
240 
241 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
242 	_sock_locks("k-sk_lock-")
243 };
244 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
245 	_sock_locks("k-slock-")
246 };
247 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
248 	_sock_locks("k-clock-")
249 };
250 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
251 	_sock_locks("rlock-")
252 };
253 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
254 	_sock_locks("wlock-")
255 };
256 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
257 	_sock_locks("elock-")
258 };
259 
260 /*
261  * sk_callback_lock and sk queues locking rules are per-address-family,
262  * so split the lock classes by using a per-AF key:
263  */
264 static struct lock_class_key af_callback_keys[AF_MAX];
265 static struct lock_class_key af_rlock_keys[AF_MAX];
266 static struct lock_class_key af_wlock_keys[AF_MAX];
267 static struct lock_class_key af_elock_keys[AF_MAX];
268 static struct lock_class_key af_kern_callback_keys[AF_MAX];
269 
270 /* Run time adjustable parameters. */
271 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
272 EXPORT_SYMBOL(sysctl_wmem_max);
273 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
274 EXPORT_SYMBOL(sysctl_rmem_max);
275 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
276 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
277 
278 /* Maximal space eaten by iovec or ancillary data plus some space */
279 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
280 EXPORT_SYMBOL(sysctl_optmem_max);
281 
282 int sysctl_tstamp_allow_data __read_mostly = 1;
283 
284 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
285 EXPORT_SYMBOL_GPL(memalloc_socks_key);
286 
287 /**
288  * sk_set_memalloc - sets %SOCK_MEMALLOC
289  * @sk: socket to set it on
290  *
291  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
292  * It's the responsibility of the admin to adjust min_free_kbytes
293  * to meet the requirements
294  */
295 void sk_set_memalloc(struct sock *sk)
296 {
297 	sock_set_flag(sk, SOCK_MEMALLOC);
298 	sk->sk_allocation |= __GFP_MEMALLOC;
299 	static_branch_inc(&memalloc_socks_key);
300 }
301 EXPORT_SYMBOL_GPL(sk_set_memalloc);
302 
303 void sk_clear_memalloc(struct sock *sk)
304 {
305 	sock_reset_flag(sk, SOCK_MEMALLOC);
306 	sk->sk_allocation &= ~__GFP_MEMALLOC;
307 	static_branch_dec(&memalloc_socks_key);
308 
309 	/*
310 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
311 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
312 	 * it has rmem allocations due to the last swapfile being deactivated
313 	 * but there is a risk that the socket is unusable due to exceeding
314 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
315 	 */
316 	sk_mem_reclaim(sk);
317 }
318 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
319 
320 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
321 {
322 	int ret;
323 	unsigned int noreclaim_flag;
324 
325 	/* these should have been dropped before queueing */
326 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
327 
328 	noreclaim_flag = memalloc_noreclaim_save();
329 	ret = sk->sk_backlog_rcv(sk, skb);
330 	memalloc_noreclaim_restore(noreclaim_flag);
331 
332 	return ret;
333 }
334 EXPORT_SYMBOL(__sk_backlog_rcv);
335 
336 void sk_error_report(struct sock *sk)
337 {
338 	sk->sk_error_report(sk);
339 
340 	switch (sk->sk_family) {
341 	case AF_INET:
342 		fallthrough;
343 	case AF_INET6:
344 		trace_inet_sk_error_report(sk);
345 		break;
346 	default:
347 		break;
348 	}
349 }
350 EXPORT_SYMBOL(sk_error_report);
351 
352 static int sock_get_timeout(long timeo, void *optval, bool old_timeval)
353 {
354 	struct __kernel_sock_timeval tv;
355 
356 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
357 		tv.tv_sec = 0;
358 		tv.tv_usec = 0;
359 	} else {
360 		tv.tv_sec = timeo / HZ;
361 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
362 	}
363 
364 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
365 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
366 		*(struct old_timeval32 *)optval = tv32;
367 		return sizeof(tv32);
368 	}
369 
370 	if (old_timeval) {
371 		struct __kernel_old_timeval old_tv;
372 		old_tv.tv_sec = tv.tv_sec;
373 		old_tv.tv_usec = tv.tv_usec;
374 		*(struct __kernel_old_timeval *)optval = old_tv;
375 		return sizeof(old_tv);
376 	}
377 
378 	*(struct __kernel_sock_timeval *)optval = tv;
379 	return sizeof(tv);
380 }
381 
382 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
383 			    bool old_timeval)
384 {
385 	struct __kernel_sock_timeval tv;
386 
387 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
388 		struct old_timeval32 tv32;
389 
390 		if (optlen < sizeof(tv32))
391 			return -EINVAL;
392 
393 		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
394 			return -EFAULT;
395 		tv.tv_sec = tv32.tv_sec;
396 		tv.tv_usec = tv32.tv_usec;
397 	} else if (old_timeval) {
398 		struct __kernel_old_timeval old_tv;
399 
400 		if (optlen < sizeof(old_tv))
401 			return -EINVAL;
402 		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
403 			return -EFAULT;
404 		tv.tv_sec = old_tv.tv_sec;
405 		tv.tv_usec = old_tv.tv_usec;
406 	} else {
407 		if (optlen < sizeof(tv))
408 			return -EINVAL;
409 		if (copy_from_sockptr(&tv, optval, sizeof(tv)))
410 			return -EFAULT;
411 	}
412 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
413 		return -EDOM;
414 
415 	if (tv.tv_sec < 0) {
416 		static int warned __read_mostly;
417 
418 		*timeo_p = 0;
419 		if (warned < 10 && net_ratelimit()) {
420 			warned++;
421 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
422 				__func__, current->comm, task_pid_nr(current));
423 		}
424 		return 0;
425 	}
426 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
427 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
428 		return 0;
429 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
430 		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
431 	return 0;
432 }
433 
434 static bool sock_needs_netstamp(const struct sock *sk)
435 {
436 	switch (sk->sk_family) {
437 	case AF_UNSPEC:
438 	case AF_UNIX:
439 		return false;
440 	default:
441 		return true;
442 	}
443 }
444 
445 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
446 {
447 	if (sk->sk_flags & flags) {
448 		sk->sk_flags &= ~flags;
449 		if (sock_needs_netstamp(sk) &&
450 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
451 			net_disable_timestamp();
452 	}
453 }
454 
455 
456 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
457 {
458 	unsigned long flags;
459 	struct sk_buff_head *list = &sk->sk_receive_queue;
460 
461 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
462 		atomic_inc(&sk->sk_drops);
463 		trace_sock_rcvqueue_full(sk, skb);
464 		return -ENOMEM;
465 	}
466 
467 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
468 		atomic_inc(&sk->sk_drops);
469 		return -ENOBUFS;
470 	}
471 
472 	skb->dev = NULL;
473 	skb_set_owner_r(skb, sk);
474 
475 	/* we escape from rcu protected region, make sure we dont leak
476 	 * a norefcounted dst
477 	 */
478 	skb_dst_force(skb);
479 
480 	spin_lock_irqsave(&list->lock, flags);
481 	sock_skb_set_dropcount(sk, skb);
482 	__skb_queue_tail(list, skb);
483 	spin_unlock_irqrestore(&list->lock, flags);
484 
485 	if (!sock_flag(sk, SOCK_DEAD))
486 		sk->sk_data_ready(sk);
487 	return 0;
488 }
489 EXPORT_SYMBOL(__sock_queue_rcv_skb);
490 
491 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
492 {
493 	int err;
494 
495 	err = sk_filter(sk, skb);
496 	if (err)
497 		return err;
498 
499 	return __sock_queue_rcv_skb(sk, skb);
500 }
501 EXPORT_SYMBOL(sock_queue_rcv_skb);
502 
503 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
504 		     const int nested, unsigned int trim_cap, bool refcounted)
505 {
506 	int rc = NET_RX_SUCCESS;
507 
508 	if (sk_filter_trim_cap(sk, skb, trim_cap))
509 		goto discard_and_relse;
510 
511 	skb->dev = NULL;
512 
513 	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
514 		atomic_inc(&sk->sk_drops);
515 		goto discard_and_relse;
516 	}
517 	if (nested)
518 		bh_lock_sock_nested(sk);
519 	else
520 		bh_lock_sock(sk);
521 	if (!sock_owned_by_user(sk)) {
522 		/*
523 		 * trylock + unlock semantics:
524 		 */
525 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
526 
527 		rc = sk_backlog_rcv(sk, skb);
528 
529 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
530 	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
531 		bh_unlock_sock(sk);
532 		atomic_inc(&sk->sk_drops);
533 		goto discard_and_relse;
534 	}
535 
536 	bh_unlock_sock(sk);
537 out:
538 	if (refcounted)
539 		sock_put(sk);
540 	return rc;
541 discard_and_relse:
542 	kfree_skb(skb);
543 	goto out;
544 }
545 EXPORT_SYMBOL(__sk_receive_skb);
546 
547 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
548 							  u32));
549 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
550 							   u32));
551 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
552 {
553 	struct dst_entry *dst = __sk_dst_get(sk);
554 
555 	if (dst && dst->obsolete &&
556 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
557 			       dst, cookie) == NULL) {
558 		sk_tx_queue_clear(sk);
559 		sk->sk_dst_pending_confirm = 0;
560 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
561 		dst_release(dst);
562 		return NULL;
563 	}
564 
565 	return dst;
566 }
567 EXPORT_SYMBOL(__sk_dst_check);
568 
569 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
570 {
571 	struct dst_entry *dst = sk_dst_get(sk);
572 
573 	if (dst && dst->obsolete &&
574 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
575 			       dst, cookie) == NULL) {
576 		sk_dst_reset(sk);
577 		dst_release(dst);
578 		return NULL;
579 	}
580 
581 	return dst;
582 }
583 EXPORT_SYMBOL(sk_dst_check);
584 
585 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
586 {
587 	int ret = -ENOPROTOOPT;
588 #ifdef CONFIG_NETDEVICES
589 	struct net *net = sock_net(sk);
590 
591 	/* Sorry... */
592 	ret = -EPERM;
593 	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
594 		goto out;
595 
596 	ret = -EINVAL;
597 	if (ifindex < 0)
598 		goto out;
599 
600 	sk->sk_bound_dev_if = ifindex;
601 	if (sk->sk_prot->rehash)
602 		sk->sk_prot->rehash(sk);
603 	sk_dst_reset(sk);
604 
605 	ret = 0;
606 
607 out:
608 #endif
609 
610 	return ret;
611 }
612 
613 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
614 {
615 	int ret;
616 
617 	if (lock_sk)
618 		lock_sock(sk);
619 	ret = sock_bindtoindex_locked(sk, ifindex);
620 	if (lock_sk)
621 		release_sock(sk);
622 
623 	return ret;
624 }
625 EXPORT_SYMBOL(sock_bindtoindex);
626 
627 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
628 {
629 	int ret = -ENOPROTOOPT;
630 #ifdef CONFIG_NETDEVICES
631 	struct net *net = sock_net(sk);
632 	char devname[IFNAMSIZ];
633 	int index;
634 
635 	ret = -EINVAL;
636 	if (optlen < 0)
637 		goto out;
638 
639 	/* Bind this socket to a particular device like "eth0",
640 	 * as specified in the passed interface name. If the
641 	 * name is "" or the option length is zero the socket
642 	 * is not bound.
643 	 */
644 	if (optlen > IFNAMSIZ - 1)
645 		optlen = IFNAMSIZ - 1;
646 	memset(devname, 0, sizeof(devname));
647 
648 	ret = -EFAULT;
649 	if (copy_from_sockptr(devname, optval, optlen))
650 		goto out;
651 
652 	index = 0;
653 	if (devname[0] != '\0') {
654 		struct net_device *dev;
655 
656 		rcu_read_lock();
657 		dev = dev_get_by_name_rcu(net, devname);
658 		if (dev)
659 			index = dev->ifindex;
660 		rcu_read_unlock();
661 		ret = -ENODEV;
662 		if (!dev)
663 			goto out;
664 	}
665 
666 	return sock_bindtoindex(sk, index, true);
667 out:
668 #endif
669 
670 	return ret;
671 }
672 
673 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
674 				int __user *optlen, int len)
675 {
676 	int ret = -ENOPROTOOPT;
677 #ifdef CONFIG_NETDEVICES
678 	struct net *net = sock_net(sk);
679 	char devname[IFNAMSIZ];
680 
681 	if (sk->sk_bound_dev_if == 0) {
682 		len = 0;
683 		goto zero;
684 	}
685 
686 	ret = -EINVAL;
687 	if (len < IFNAMSIZ)
688 		goto out;
689 
690 	ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
691 	if (ret)
692 		goto out;
693 
694 	len = strlen(devname) + 1;
695 
696 	ret = -EFAULT;
697 	if (copy_to_user(optval, devname, len))
698 		goto out;
699 
700 zero:
701 	ret = -EFAULT;
702 	if (put_user(len, optlen))
703 		goto out;
704 
705 	ret = 0;
706 
707 out:
708 #endif
709 
710 	return ret;
711 }
712 
713 bool sk_mc_loop(struct sock *sk)
714 {
715 	if (dev_recursion_level())
716 		return false;
717 	if (!sk)
718 		return true;
719 	switch (sk->sk_family) {
720 	case AF_INET:
721 		return inet_sk(sk)->mc_loop;
722 #if IS_ENABLED(CONFIG_IPV6)
723 	case AF_INET6:
724 		return inet6_sk(sk)->mc_loop;
725 #endif
726 	}
727 	WARN_ON_ONCE(1);
728 	return true;
729 }
730 EXPORT_SYMBOL(sk_mc_loop);
731 
732 void sock_set_reuseaddr(struct sock *sk)
733 {
734 	lock_sock(sk);
735 	sk->sk_reuse = SK_CAN_REUSE;
736 	release_sock(sk);
737 }
738 EXPORT_SYMBOL(sock_set_reuseaddr);
739 
740 void sock_set_reuseport(struct sock *sk)
741 {
742 	lock_sock(sk);
743 	sk->sk_reuseport = true;
744 	release_sock(sk);
745 }
746 EXPORT_SYMBOL(sock_set_reuseport);
747 
748 void sock_no_linger(struct sock *sk)
749 {
750 	lock_sock(sk);
751 	sk->sk_lingertime = 0;
752 	sock_set_flag(sk, SOCK_LINGER);
753 	release_sock(sk);
754 }
755 EXPORT_SYMBOL(sock_no_linger);
756 
757 void sock_set_priority(struct sock *sk, u32 priority)
758 {
759 	lock_sock(sk);
760 	sk->sk_priority = priority;
761 	release_sock(sk);
762 }
763 EXPORT_SYMBOL(sock_set_priority);
764 
765 void sock_set_sndtimeo(struct sock *sk, s64 secs)
766 {
767 	lock_sock(sk);
768 	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
769 		sk->sk_sndtimeo = secs * HZ;
770 	else
771 		sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
772 	release_sock(sk);
773 }
774 EXPORT_SYMBOL(sock_set_sndtimeo);
775 
776 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
777 {
778 	if (val)  {
779 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
780 		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
781 		sock_set_flag(sk, SOCK_RCVTSTAMP);
782 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
783 	} else {
784 		sock_reset_flag(sk, SOCK_RCVTSTAMP);
785 		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
786 	}
787 }
788 
789 void sock_enable_timestamps(struct sock *sk)
790 {
791 	lock_sock(sk);
792 	__sock_set_timestamps(sk, true, false, true);
793 	release_sock(sk);
794 }
795 EXPORT_SYMBOL(sock_enable_timestamps);
796 
797 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
798 {
799 	switch (optname) {
800 	case SO_TIMESTAMP_OLD:
801 		__sock_set_timestamps(sk, valbool, false, false);
802 		break;
803 	case SO_TIMESTAMP_NEW:
804 		__sock_set_timestamps(sk, valbool, true, false);
805 		break;
806 	case SO_TIMESTAMPNS_OLD:
807 		__sock_set_timestamps(sk, valbool, false, true);
808 		break;
809 	case SO_TIMESTAMPNS_NEW:
810 		__sock_set_timestamps(sk, valbool, true, true);
811 		break;
812 	}
813 }
814 
815 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
816 {
817 	struct net *net = sock_net(sk);
818 	struct net_device *dev = NULL;
819 	bool match = false;
820 	int *vclock_index;
821 	int i, num;
822 
823 	if (sk->sk_bound_dev_if)
824 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
825 
826 	if (!dev) {
827 		pr_err("%s: sock not bind to device\n", __func__);
828 		return -EOPNOTSUPP;
829 	}
830 
831 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
832 	for (i = 0; i < num; i++) {
833 		if (*(vclock_index + i) == phc_index) {
834 			match = true;
835 			break;
836 		}
837 	}
838 
839 	if (num > 0)
840 		kfree(vclock_index);
841 
842 	if (!match)
843 		return -EINVAL;
844 
845 	sk->sk_bind_phc = phc_index;
846 
847 	return 0;
848 }
849 
850 int sock_set_timestamping(struct sock *sk, int optname,
851 			  struct so_timestamping timestamping)
852 {
853 	int val = timestamping.flags;
854 	int ret;
855 
856 	if (val & ~SOF_TIMESTAMPING_MASK)
857 		return -EINVAL;
858 
859 	if (val & SOF_TIMESTAMPING_OPT_ID &&
860 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
861 		if (sk->sk_protocol == IPPROTO_TCP &&
862 		    sk->sk_type == SOCK_STREAM) {
863 			if ((1 << sk->sk_state) &
864 			    (TCPF_CLOSE | TCPF_LISTEN))
865 				return -EINVAL;
866 			sk->sk_tskey = tcp_sk(sk)->snd_una;
867 		} else {
868 			sk->sk_tskey = 0;
869 		}
870 	}
871 
872 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
873 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
874 		return -EINVAL;
875 
876 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
877 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
878 		if (ret)
879 			return ret;
880 	}
881 
882 	sk->sk_tsflags = val;
883 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
884 
885 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
886 		sock_enable_timestamp(sk,
887 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
888 	else
889 		sock_disable_timestamp(sk,
890 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
891 	return 0;
892 }
893 
894 void sock_set_keepalive(struct sock *sk)
895 {
896 	lock_sock(sk);
897 	if (sk->sk_prot->keepalive)
898 		sk->sk_prot->keepalive(sk, true);
899 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
900 	release_sock(sk);
901 }
902 EXPORT_SYMBOL(sock_set_keepalive);
903 
904 static void __sock_set_rcvbuf(struct sock *sk, int val)
905 {
906 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
907 	 * as a negative value.
908 	 */
909 	val = min_t(int, val, INT_MAX / 2);
910 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
911 
912 	/* We double it on the way in to account for "struct sk_buff" etc.
913 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
914 	 * will allow that much actual data to be received on that socket.
915 	 *
916 	 * Applications are unaware that "struct sk_buff" and other overheads
917 	 * allocate from the receive buffer during socket buffer allocation.
918 	 *
919 	 * And after considering the possible alternatives, returning the value
920 	 * we actually used in getsockopt is the most desirable behavior.
921 	 */
922 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
923 }
924 
925 void sock_set_rcvbuf(struct sock *sk, int val)
926 {
927 	lock_sock(sk);
928 	__sock_set_rcvbuf(sk, val);
929 	release_sock(sk);
930 }
931 EXPORT_SYMBOL(sock_set_rcvbuf);
932 
933 static void __sock_set_mark(struct sock *sk, u32 val)
934 {
935 	if (val != sk->sk_mark) {
936 		sk->sk_mark = val;
937 		sk_dst_reset(sk);
938 	}
939 }
940 
941 void sock_set_mark(struct sock *sk, u32 val)
942 {
943 	lock_sock(sk);
944 	__sock_set_mark(sk, val);
945 	release_sock(sk);
946 }
947 EXPORT_SYMBOL(sock_set_mark);
948 
949 /*
950  *	This is meant for all protocols to use and covers goings on
951  *	at the socket level. Everything here is generic.
952  */
953 
954 int sock_setsockopt(struct socket *sock, int level, int optname,
955 		    sockptr_t optval, unsigned int optlen)
956 {
957 	struct so_timestamping timestamping;
958 	struct sock_txtime sk_txtime;
959 	struct sock *sk = sock->sk;
960 	int val;
961 	int valbool;
962 	struct linger ling;
963 	int ret = 0;
964 
965 	/*
966 	 *	Options without arguments
967 	 */
968 
969 	if (optname == SO_BINDTODEVICE)
970 		return sock_setbindtodevice(sk, optval, optlen);
971 
972 	if (optlen < sizeof(int))
973 		return -EINVAL;
974 
975 	if (copy_from_sockptr(&val, optval, sizeof(val)))
976 		return -EFAULT;
977 
978 	valbool = val ? 1 : 0;
979 
980 	lock_sock(sk);
981 
982 	switch (optname) {
983 	case SO_DEBUG:
984 		if (val && !capable(CAP_NET_ADMIN))
985 			ret = -EACCES;
986 		else
987 			sock_valbool_flag(sk, SOCK_DBG, valbool);
988 		break;
989 	case SO_REUSEADDR:
990 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
991 		break;
992 	case SO_REUSEPORT:
993 		sk->sk_reuseport = valbool;
994 		break;
995 	case SO_TYPE:
996 	case SO_PROTOCOL:
997 	case SO_DOMAIN:
998 	case SO_ERROR:
999 		ret = -ENOPROTOOPT;
1000 		break;
1001 	case SO_DONTROUTE:
1002 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1003 		sk_dst_reset(sk);
1004 		break;
1005 	case SO_BROADCAST:
1006 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1007 		break;
1008 	case SO_SNDBUF:
1009 		/* Don't error on this BSD doesn't and if you think
1010 		 * about it this is right. Otherwise apps have to
1011 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1012 		 * are treated in BSD as hints
1013 		 */
1014 		val = min_t(u32, val, sysctl_wmem_max);
1015 set_sndbuf:
1016 		/* Ensure val * 2 fits into an int, to prevent max_t()
1017 		 * from treating it as a negative value.
1018 		 */
1019 		val = min_t(int, val, INT_MAX / 2);
1020 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1021 		WRITE_ONCE(sk->sk_sndbuf,
1022 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1023 		/* Wake up sending tasks if we upped the value. */
1024 		sk->sk_write_space(sk);
1025 		break;
1026 
1027 	case SO_SNDBUFFORCE:
1028 		if (!capable(CAP_NET_ADMIN)) {
1029 			ret = -EPERM;
1030 			break;
1031 		}
1032 
1033 		/* No negative values (to prevent underflow, as val will be
1034 		 * multiplied by 2).
1035 		 */
1036 		if (val < 0)
1037 			val = 0;
1038 		goto set_sndbuf;
1039 
1040 	case SO_RCVBUF:
1041 		/* Don't error on this BSD doesn't and if you think
1042 		 * about it this is right. Otherwise apps have to
1043 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1044 		 * are treated in BSD as hints
1045 		 */
1046 		__sock_set_rcvbuf(sk, min_t(u32, val, sysctl_rmem_max));
1047 		break;
1048 
1049 	case SO_RCVBUFFORCE:
1050 		if (!capable(CAP_NET_ADMIN)) {
1051 			ret = -EPERM;
1052 			break;
1053 		}
1054 
1055 		/* No negative values (to prevent underflow, as val will be
1056 		 * multiplied by 2).
1057 		 */
1058 		__sock_set_rcvbuf(sk, max(val, 0));
1059 		break;
1060 
1061 	case SO_KEEPALIVE:
1062 		if (sk->sk_prot->keepalive)
1063 			sk->sk_prot->keepalive(sk, valbool);
1064 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1065 		break;
1066 
1067 	case SO_OOBINLINE:
1068 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1069 		break;
1070 
1071 	case SO_NO_CHECK:
1072 		sk->sk_no_check_tx = valbool;
1073 		break;
1074 
1075 	case SO_PRIORITY:
1076 		if ((val >= 0 && val <= 6) ||
1077 		    ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1078 			sk->sk_priority = val;
1079 		else
1080 			ret = -EPERM;
1081 		break;
1082 
1083 	case SO_LINGER:
1084 		if (optlen < sizeof(ling)) {
1085 			ret = -EINVAL;	/* 1003.1g */
1086 			break;
1087 		}
1088 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1089 			ret = -EFAULT;
1090 			break;
1091 		}
1092 		if (!ling.l_onoff)
1093 			sock_reset_flag(sk, SOCK_LINGER);
1094 		else {
1095 #if (BITS_PER_LONG == 32)
1096 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
1097 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
1098 			else
1099 #endif
1100 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
1101 			sock_set_flag(sk, SOCK_LINGER);
1102 		}
1103 		break;
1104 
1105 	case SO_BSDCOMPAT:
1106 		break;
1107 
1108 	case SO_PASSCRED:
1109 		if (valbool)
1110 			set_bit(SOCK_PASSCRED, &sock->flags);
1111 		else
1112 			clear_bit(SOCK_PASSCRED, &sock->flags);
1113 		break;
1114 
1115 	case SO_TIMESTAMP_OLD:
1116 	case SO_TIMESTAMP_NEW:
1117 	case SO_TIMESTAMPNS_OLD:
1118 	case SO_TIMESTAMPNS_NEW:
1119 		sock_set_timestamp(sk, optname, valbool);
1120 		break;
1121 
1122 	case SO_TIMESTAMPING_NEW:
1123 	case SO_TIMESTAMPING_OLD:
1124 		if (optlen == sizeof(timestamping)) {
1125 			if (copy_from_sockptr(&timestamping, optval,
1126 					      sizeof(timestamping))) {
1127 				ret = -EFAULT;
1128 				break;
1129 			}
1130 		} else {
1131 			memset(&timestamping, 0, sizeof(timestamping));
1132 			timestamping.flags = val;
1133 		}
1134 		ret = sock_set_timestamping(sk, optname, timestamping);
1135 		break;
1136 
1137 	case SO_RCVLOWAT:
1138 		if (val < 0)
1139 			val = INT_MAX;
1140 		if (sock->ops->set_rcvlowat)
1141 			ret = sock->ops->set_rcvlowat(sk, val);
1142 		else
1143 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1144 		break;
1145 
1146 	case SO_RCVTIMEO_OLD:
1147 	case SO_RCVTIMEO_NEW:
1148 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1149 				       optlen, optname == SO_RCVTIMEO_OLD);
1150 		break;
1151 
1152 	case SO_SNDTIMEO_OLD:
1153 	case SO_SNDTIMEO_NEW:
1154 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1155 				       optlen, optname == SO_SNDTIMEO_OLD);
1156 		break;
1157 
1158 	case SO_ATTACH_FILTER: {
1159 		struct sock_fprog fprog;
1160 
1161 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1162 		if (!ret)
1163 			ret = sk_attach_filter(&fprog, sk);
1164 		break;
1165 	}
1166 	case SO_ATTACH_BPF:
1167 		ret = -EINVAL;
1168 		if (optlen == sizeof(u32)) {
1169 			u32 ufd;
1170 
1171 			ret = -EFAULT;
1172 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1173 				break;
1174 
1175 			ret = sk_attach_bpf(ufd, sk);
1176 		}
1177 		break;
1178 
1179 	case SO_ATTACH_REUSEPORT_CBPF: {
1180 		struct sock_fprog fprog;
1181 
1182 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1183 		if (!ret)
1184 			ret = sk_reuseport_attach_filter(&fprog, sk);
1185 		break;
1186 	}
1187 	case SO_ATTACH_REUSEPORT_EBPF:
1188 		ret = -EINVAL;
1189 		if (optlen == sizeof(u32)) {
1190 			u32 ufd;
1191 
1192 			ret = -EFAULT;
1193 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1194 				break;
1195 
1196 			ret = sk_reuseport_attach_bpf(ufd, sk);
1197 		}
1198 		break;
1199 
1200 	case SO_DETACH_REUSEPORT_BPF:
1201 		ret = reuseport_detach_prog(sk);
1202 		break;
1203 
1204 	case SO_DETACH_FILTER:
1205 		ret = sk_detach_filter(sk);
1206 		break;
1207 
1208 	case SO_LOCK_FILTER:
1209 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1210 			ret = -EPERM;
1211 		else
1212 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1213 		break;
1214 
1215 	case SO_PASSSEC:
1216 		if (valbool)
1217 			set_bit(SOCK_PASSSEC, &sock->flags);
1218 		else
1219 			clear_bit(SOCK_PASSSEC, &sock->flags);
1220 		break;
1221 	case SO_MARK:
1222 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1223 			ret = -EPERM;
1224 			break;
1225 		}
1226 
1227 		__sock_set_mark(sk, val);
1228 		break;
1229 
1230 	case SO_RXQ_OVFL:
1231 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1232 		break;
1233 
1234 	case SO_WIFI_STATUS:
1235 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1236 		break;
1237 
1238 	case SO_PEEK_OFF:
1239 		if (sock->ops->set_peek_off)
1240 			ret = sock->ops->set_peek_off(sk, val);
1241 		else
1242 			ret = -EOPNOTSUPP;
1243 		break;
1244 
1245 	case SO_NOFCS:
1246 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1247 		break;
1248 
1249 	case SO_SELECT_ERR_QUEUE:
1250 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1251 		break;
1252 
1253 #ifdef CONFIG_NET_RX_BUSY_POLL
1254 	case SO_BUSY_POLL:
1255 		/* allow unprivileged users to decrease the value */
1256 		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1257 			ret = -EPERM;
1258 		else {
1259 			if (val < 0)
1260 				ret = -EINVAL;
1261 			else
1262 				WRITE_ONCE(sk->sk_ll_usec, val);
1263 		}
1264 		break;
1265 	case SO_PREFER_BUSY_POLL:
1266 		if (valbool && !capable(CAP_NET_ADMIN))
1267 			ret = -EPERM;
1268 		else
1269 			WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1270 		break;
1271 	case SO_BUSY_POLL_BUDGET:
1272 		if (val > READ_ONCE(sk->sk_busy_poll_budget) && !capable(CAP_NET_ADMIN)) {
1273 			ret = -EPERM;
1274 		} else {
1275 			if (val < 0 || val > U16_MAX)
1276 				ret = -EINVAL;
1277 			else
1278 				WRITE_ONCE(sk->sk_busy_poll_budget, val);
1279 		}
1280 		break;
1281 #endif
1282 
1283 	case SO_MAX_PACING_RATE:
1284 		{
1285 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1286 
1287 		if (sizeof(ulval) != sizeof(val) &&
1288 		    optlen >= sizeof(ulval) &&
1289 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1290 			ret = -EFAULT;
1291 			break;
1292 		}
1293 		if (ulval != ~0UL)
1294 			cmpxchg(&sk->sk_pacing_status,
1295 				SK_PACING_NONE,
1296 				SK_PACING_NEEDED);
1297 		sk->sk_max_pacing_rate = ulval;
1298 		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1299 		break;
1300 		}
1301 	case SO_INCOMING_CPU:
1302 		WRITE_ONCE(sk->sk_incoming_cpu, val);
1303 		break;
1304 
1305 	case SO_CNX_ADVICE:
1306 		if (val == 1)
1307 			dst_negative_advice(sk);
1308 		break;
1309 
1310 	case SO_ZEROCOPY:
1311 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1312 			if (!((sk->sk_type == SOCK_STREAM &&
1313 			       sk->sk_protocol == IPPROTO_TCP) ||
1314 			      (sk->sk_type == SOCK_DGRAM &&
1315 			       sk->sk_protocol == IPPROTO_UDP)))
1316 				ret = -ENOTSUPP;
1317 		} else if (sk->sk_family != PF_RDS) {
1318 			ret = -ENOTSUPP;
1319 		}
1320 		if (!ret) {
1321 			if (val < 0 || val > 1)
1322 				ret = -EINVAL;
1323 			else
1324 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1325 		}
1326 		break;
1327 
1328 	case SO_TXTIME:
1329 		if (optlen != sizeof(struct sock_txtime)) {
1330 			ret = -EINVAL;
1331 			break;
1332 		} else if (copy_from_sockptr(&sk_txtime, optval,
1333 			   sizeof(struct sock_txtime))) {
1334 			ret = -EFAULT;
1335 			break;
1336 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1337 			ret = -EINVAL;
1338 			break;
1339 		}
1340 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1341 		 * scheduler has enough safe guards.
1342 		 */
1343 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1344 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1345 			ret = -EPERM;
1346 			break;
1347 		}
1348 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1349 		sk->sk_clockid = sk_txtime.clockid;
1350 		sk->sk_txtime_deadline_mode =
1351 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1352 		sk->sk_txtime_report_errors =
1353 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1354 		break;
1355 
1356 	case SO_BINDTOIFINDEX:
1357 		ret = sock_bindtoindex_locked(sk, val);
1358 		break;
1359 
1360 	default:
1361 		ret = -ENOPROTOOPT;
1362 		break;
1363 	}
1364 	release_sock(sk);
1365 	return ret;
1366 }
1367 EXPORT_SYMBOL(sock_setsockopt);
1368 
1369 
1370 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1371 			  struct ucred *ucred)
1372 {
1373 	ucred->pid = pid_vnr(pid);
1374 	ucred->uid = ucred->gid = -1;
1375 	if (cred) {
1376 		struct user_namespace *current_ns = current_user_ns();
1377 
1378 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1379 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1380 	}
1381 }
1382 
1383 static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1384 {
1385 	struct user_namespace *user_ns = current_user_ns();
1386 	int i;
1387 
1388 	for (i = 0; i < src->ngroups; i++)
1389 		if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1390 			return -EFAULT;
1391 
1392 	return 0;
1393 }
1394 
1395 int sock_getsockopt(struct socket *sock, int level, int optname,
1396 		    char __user *optval, int __user *optlen)
1397 {
1398 	struct sock *sk = sock->sk;
1399 
1400 	union {
1401 		int val;
1402 		u64 val64;
1403 		unsigned long ulval;
1404 		struct linger ling;
1405 		struct old_timeval32 tm32;
1406 		struct __kernel_old_timeval tm;
1407 		struct  __kernel_sock_timeval stm;
1408 		struct sock_txtime txtime;
1409 		struct so_timestamping timestamping;
1410 	} v;
1411 
1412 	int lv = sizeof(int);
1413 	int len;
1414 
1415 	if (get_user(len, optlen))
1416 		return -EFAULT;
1417 	if (len < 0)
1418 		return -EINVAL;
1419 
1420 	memset(&v, 0, sizeof(v));
1421 
1422 	switch (optname) {
1423 	case SO_DEBUG:
1424 		v.val = sock_flag(sk, SOCK_DBG);
1425 		break;
1426 
1427 	case SO_DONTROUTE:
1428 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1429 		break;
1430 
1431 	case SO_BROADCAST:
1432 		v.val = sock_flag(sk, SOCK_BROADCAST);
1433 		break;
1434 
1435 	case SO_SNDBUF:
1436 		v.val = sk->sk_sndbuf;
1437 		break;
1438 
1439 	case SO_RCVBUF:
1440 		v.val = sk->sk_rcvbuf;
1441 		break;
1442 
1443 	case SO_REUSEADDR:
1444 		v.val = sk->sk_reuse;
1445 		break;
1446 
1447 	case SO_REUSEPORT:
1448 		v.val = sk->sk_reuseport;
1449 		break;
1450 
1451 	case SO_KEEPALIVE:
1452 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1453 		break;
1454 
1455 	case SO_TYPE:
1456 		v.val = sk->sk_type;
1457 		break;
1458 
1459 	case SO_PROTOCOL:
1460 		v.val = sk->sk_protocol;
1461 		break;
1462 
1463 	case SO_DOMAIN:
1464 		v.val = sk->sk_family;
1465 		break;
1466 
1467 	case SO_ERROR:
1468 		v.val = -sock_error(sk);
1469 		if (v.val == 0)
1470 			v.val = xchg(&sk->sk_err_soft, 0);
1471 		break;
1472 
1473 	case SO_OOBINLINE:
1474 		v.val = sock_flag(sk, SOCK_URGINLINE);
1475 		break;
1476 
1477 	case SO_NO_CHECK:
1478 		v.val = sk->sk_no_check_tx;
1479 		break;
1480 
1481 	case SO_PRIORITY:
1482 		v.val = sk->sk_priority;
1483 		break;
1484 
1485 	case SO_LINGER:
1486 		lv		= sizeof(v.ling);
1487 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1488 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1489 		break;
1490 
1491 	case SO_BSDCOMPAT:
1492 		break;
1493 
1494 	case SO_TIMESTAMP_OLD:
1495 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1496 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1497 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1498 		break;
1499 
1500 	case SO_TIMESTAMPNS_OLD:
1501 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1502 		break;
1503 
1504 	case SO_TIMESTAMP_NEW:
1505 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1506 		break;
1507 
1508 	case SO_TIMESTAMPNS_NEW:
1509 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1510 		break;
1511 
1512 	case SO_TIMESTAMPING_OLD:
1513 		lv = sizeof(v.timestamping);
1514 		v.timestamping.flags = sk->sk_tsflags;
1515 		v.timestamping.bind_phc = sk->sk_bind_phc;
1516 		break;
1517 
1518 	case SO_RCVTIMEO_OLD:
1519 	case SO_RCVTIMEO_NEW:
1520 		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1521 		break;
1522 
1523 	case SO_SNDTIMEO_OLD:
1524 	case SO_SNDTIMEO_NEW:
1525 		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1526 		break;
1527 
1528 	case SO_RCVLOWAT:
1529 		v.val = sk->sk_rcvlowat;
1530 		break;
1531 
1532 	case SO_SNDLOWAT:
1533 		v.val = 1;
1534 		break;
1535 
1536 	case SO_PASSCRED:
1537 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1538 		break;
1539 
1540 	case SO_PEERCRED:
1541 	{
1542 		struct ucred peercred;
1543 		if (len > sizeof(peercred))
1544 			len = sizeof(peercred);
1545 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1546 		if (copy_to_user(optval, &peercred, len))
1547 			return -EFAULT;
1548 		goto lenout;
1549 	}
1550 
1551 	case SO_PEERGROUPS:
1552 	{
1553 		int ret, n;
1554 
1555 		if (!sk->sk_peer_cred)
1556 			return -ENODATA;
1557 
1558 		n = sk->sk_peer_cred->group_info->ngroups;
1559 		if (len < n * sizeof(gid_t)) {
1560 			len = n * sizeof(gid_t);
1561 			return put_user(len, optlen) ? -EFAULT : -ERANGE;
1562 		}
1563 		len = n * sizeof(gid_t);
1564 
1565 		ret = groups_to_user((gid_t __user *)optval,
1566 				     sk->sk_peer_cred->group_info);
1567 		if (ret)
1568 			return ret;
1569 		goto lenout;
1570 	}
1571 
1572 	case SO_PEERNAME:
1573 	{
1574 		char address[128];
1575 
1576 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1577 		if (lv < 0)
1578 			return -ENOTCONN;
1579 		if (lv < len)
1580 			return -EINVAL;
1581 		if (copy_to_user(optval, address, len))
1582 			return -EFAULT;
1583 		goto lenout;
1584 	}
1585 
1586 	/* Dubious BSD thing... Probably nobody even uses it, but
1587 	 * the UNIX standard wants it for whatever reason... -DaveM
1588 	 */
1589 	case SO_ACCEPTCONN:
1590 		v.val = sk->sk_state == TCP_LISTEN;
1591 		break;
1592 
1593 	case SO_PASSSEC:
1594 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1595 		break;
1596 
1597 	case SO_PEERSEC:
1598 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1599 
1600 	case SO_MARK:
1601 		v.val = sk->sk_mark;
1602 		break;
1603 
1604 	case SO_RXQ_OVFL:
1605 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1606 		break;
1607 
1608 	case SO_WIFI_STATUS:
1609 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1610 		break;
1611 
1612 	case SO_PEEK_OFF:
1613 		if (!sock->ops->set_peek_off)
1614 			return -EOPNOTSUPP;
1615 
1616 		v.val = sk->sk_peek_off;
1617 		break;
1618 	case SO_NOFCS:
1619 		v.val = sock_flag(sk, SOCK_NOFCS);
1620 		break;
1621 
1622 	case SO_BINDTODEVICE:
1623 		return sock_getbindtodevice(sk, optval, optlen, len);
1624 
1625 	case SO_GET_FILTER:
1626 		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1627 		if (len < 0)
1628 			return len;
1629 
1630 		goto lenout;
1631 
1632 	case SO_LOCK_FILTER:
1633 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1634 		break;
1635 
1636 	case SO_BPF_EXTENSIONS:
1637 		v.val = bpf_tell_extensions();
1638 		break;
1639 
1640 	case SO_SELECT_ERR_QUEUE:
1641 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1642 		break;
1643 
1644 #ifdef CONFIG_NET_RX_BUSY_POLL
1645 	case SO_BUSY_POLL:
1646 		v.val = sk->sk_ll_usec;
1647 		break;
1648 	case SO_PREFER_BUSY_POLL:
1649 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1650 		break;
1651 #endif
1652 
1653 	case SO_MAX_PACING_RATE:
1654 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1655 			lv = sizeof(v.ulval);
1656 			v.ulval = sk->sk_max_pacing_rate;
1657 		} else {
1658 			/* 32bit version */
1659 			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1660 		}
1661 		break;
1662 
1663 	case SO_INCOMING_CPU:
1664 		v.val = READ_ONCE(sk->sk_incoming_cpu);
1665 		break;
1666 
1667 	case SO_MEMINFO:
1668 	{
1669 		u32 meminfo[SK_MEMINFO_VARS];
1670 
1671 		sk_get_meminfo(sk, meminfo);
1672 
1673 		len = min_t(unsigned int, len, sizeof(meminfo));
1674 		if (copy_to_user(optval, &meminfo, len))
1675 			return -EFAULT;
1676 
1677 		goto lenout;
1678 	}
1679 
1680 #ifdef CONFIG_NET_RX_BUSY_POLL
1681 	case SO_INCOMING_NAPI_ID:
1682 		v.val = READ_ONCE(sk->sk_napi_id);
1683 
1684 		/* aggregate non-NAPI IDs down to 0 */
1685 		if (v.val < MIN_NAPI_ID)
1686 			v.val = 0;
1687 
1688 		break;
1689 #endif
1690 
1691 	case SO_COOKIE:
1692 		lv = sizeof(u64);
1693 		if (len < lv)
1694 			return -EINVAL;
1695 		v.val64 = sock_gen_cookie(sk);
1696 		break;
1697 
1698 	case SO_ZEROCOPY:
1699 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1700 		break;
1701 
1702 	case SO_TXTIME:
1703 		lv = sizeof(v.txtime);
1704 		v.txtime.clockid = sk->sk_clockid;
1705 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1706 				  SOF_TXTIME_DEADLINE_MODE : 0;
1707 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1708 				  SOF_TXTIME_REPORT_ERRORS : 0;
1709 		break;
1710 
1711 	case SO_BINDTOIFINDEX:
1712 		v.val = sk->sk_bound_dev_if;
1713 		break;
1714 
1715 	case SO_NETNS_COOKIE:
1716 		lv = sizeof(u64);
1717 		if (len != lv)
1718 			return -EINVAL;
1719 		v.val64 = sock_net(sk)->net_cookie;
1720 		break;
1721 
1722 	default:
1723 		/* We implement the SO_SNDLOWAT etc to not be settable
1724 		 * (1003.1g 7).
1725 		 */
1726 		return -ENOPROTOOPT;
1727 	}
1728 
1729 	if (len > lv)
1730 		len = lv;
1731 	if (copy_to_user(optval, &v, len))
1732 		return -EFAULT;
1733 lenout:
1734 	if (put_user(len, optlen))
1735 		return -EFAULT;
1736 	return 0;
1737 }
1738 
1739 /*
1740  * Initialize an sk_lock.
1741  *
1742  * (We also register the sk_lock with the lock validator.)
1743  */
1744 static inline void sock_lock_init(struct sock *sk)
1745 {
1746 	if (sk->sk_kern_sock)
1747 		sock_lock_init_class_and_name(
1748 			sk,
1749 			af_family_kern_slock_key_strings[sk->sk_family],
1750 			af_family_kern_slock_keys + sk->sk_family,
1751 			af_family_kern_key_strings[sk->sk_family],
1752 			af_family_kern_keys + sk->sk_family);
1753 	else
1754 		sock_lock_init_class_and_name(
1755 			sk,
1756 			af_family_slock_key_strings[sk->sk_family],
1757 			af_family_slock_keys + sk->sk_family,
1758 			af_family_key_strings[sk->sk_family],
1759 			af_family_keys + sk->sk_family);
1760 }
1761 
1762 /*
1763  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1764  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1765  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1766  */
1767 static void sock_copy(struct sock *nsk, const struct sock *osk)
1768 {
1769 	const struct proto *prot = READ_ONCE(osk->sk_prot);
1770 #ifdef CONFIG_SECURITY_NETWORK
1771 	void *sptr = nsk->sk_security;
1772 #endif
1773 
1774 	/* If we move sk_tx_queue_mapping out of the private section,
1775 	 * we must check if sk_tx_queue_clear() is called after
1776 	 * sock_copy() in sk_clone_lock().
1777 	 */
1778 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
1779 		     offsetof(struct sock, sk_dontcopy_begin) ||
1780 		     offsetof(struct sock, sk_tx_queue_mapping) >=
1781 		     offsetof(struct sock, sk_dontcopy_end));
1782 
1783 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1784 
1785 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1786 	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1787 
1788 #ifdef CONFIG_SECURITY_NETWORK
1789 	nsk->sk_security = sptr;
1790 	security_sk_clone(osk, nsk);
1791 #endif
1792 }
1793 
1794 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1795 		int family)
1796 {
1797 	struct sock *sk;
1798 	struct kmem_cache *slab;
1799 
1800 	slab = prot->slab;
1801 	if (slab != NULL) {
1802 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1803 		if (!sk)
1804 			return sk;
1805 		if (want_init_on_alloc(priority))
1806 			sk_prot_clear_nulls(sk, prot->obj_size);
1807 	} else
1808 		sk = kmalloc(prot->obj_size, priority);
1809 
1810 	if (sk != NULL) {
1811 		if (security_sk_alloc(sk, family, priority))
1812 			goto out_free;
1813 
1814 		if (!try_module_get(prot->owner))
1815 			goto out_free_sec;
1816 	}
1817 
1818 	return sk;
1819 
1820 out_free_sec:
1821 	security_sk_free(sk);
1822 out_free:
1823 	if (slab != NULL)
1824 		kmem_cache_free(slab, sk);
1825 	else
1826 		kfree(sk);
1827 	return NULL;
1828 }
1829 
1830 static void sk_prot_free(struct proto *prot, struct sock *sk)
1831 {
1832 	struct kmem_cache *slab;
1833 	struct module *owner;
1834 
1835 	owner = prot->owner;
1836 	slab = prot->slab;
1837 
1838 	cgroup_sk_free(&sk->sk_cgrp_data);
1839 	mem_cgroup_sk_free(sk);
1840 	security_sk_free(sk);
1841 	if (slab != NULL)
1842 		kmem_cache_free(slab, sk);
1843 	else
1844 		kfree(sk);
1845 	module_put(owner);
1846 }
1847 
1848 /**
1849  *	sk_alloc - All socket objects are allocated here
1850  *	@net: the applicable net namespace
1851  *	@family: protocol family
1852  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1853  *	@prot: struct proto associated with this new sock instance
1854  *	@kern: is this to be a kernel socket?
1855  */
1856 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1857 		      struct proto *prot, int kern)
1858 {
1859 	struct sock *sk;
1860 
1861 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1862 	if (sk) {
1863 		sk->sk_family = family;
1864 		/*
1865 		 * See comment in struct sock definition to understand
1866 		 * why we need sk_prot_creator -acme
1867 		 */
1868 		sk->sk_prot = sk->sk_prot_creator = prot;
1869 		sk->sk_kern_sock = kern;
1870 		sock_lock_init(sk);
1871 		sk->sk_net_refcnt = kern ? 0 : 1;
1872 		if (likely(sk->sk_net_refcnt)) {
1873 			get_net(net);
1874 			sock_inuse_add(net, 1);
1875 		}
1876 
1877 		sock_net_set(sk, net);
1878 		refcount_set(&sk->sk_wmem_alloc, 1);
1879 
1880 		mem_cgroup_sk_alloc(sk);
1881 		cgroup_sk_alloc(&sk->sk_cgrp_data);
1882 		sock_update_classid(&sk->sk_cgrp_data);
1883 		sock_update_netprioidx(&sk->sk_cgrp_data);
1884 		sk_tx_queue_clear(sk);
1885 	}
1886 
1887 	return sk;
1888 }
1889 EXPORT_SYMBOL(sk_alloc);
1890 
1891 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
1892  * grace period. This is the case for UDP sockets and TCP listeners.
1893  */
1894 static void __sk_destruct(struct rcu_head *head)
1895 {
1896 	struct sock *sk = container_of(head, struct sock, sk_rcu);
1897 	struct sk_filter *filter;
1898 
1899 	if (sk->sk_destruct)
1900 		sk->sk_destruct(sk);
1901 
1902 	filter = rcu_dereference_check(sk->sk_filter,
1903 				       refcount_read(&sk->sk_wmem_alloc) == 0);
1904 	if (filter) {
1905 		sk_filter_uncharge(sk, filter);
1906 		RCU_INIT_POINTER(sk->sk_filter, NULL);
1907 	}
1908 
1909 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1910 
1911 #ifdef CONFIG_BPF_SYSCALL
1912 	bpf_sk_storage_free(sk);
1913 #endif
1914 
1915 	if (atomic_read(&sk->sk_omem_alloc))
1916 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1917 			 __func__, atomic_read(&sk->sk_omem_alloc));
1918 
1919 	if (sk->sk_frag.page) {
1920 		put_page(sk->sk_frag.page);
1921 		sk->sk_frag.page = NULL;
1922 	}
1923 
1924 	if (sk->sk_peer_cred)
1925 		put_cred(sk->sk_peer_cred);
1926 	put_pid(sk->sk_peer_pid);
1927 	if (likely(sk->sk_net_refcnt))
1928 		put_net(sock_net(sk));
1929 	sk_prot_free(sk->sk_prot_creator, sk);
1930 }
1931 
1932 void sk_destruct(struct sock *sk)
1933 {
1934 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
1935 
1936 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
1937 		reuseport_detach_sock(sk);
1938 		use_call_rcu = true;
1939 	}
1940 
1941 	if (use_call_rcu)
1942 		call_rcu(&sk->sk_rcu, __sk_destruct);
1943 	else
1944 		__sk_destruct(&sk->sk_rcu);
1945 }
1946 
1947 static void __sk_free(struct sock *sk)
1948 {
1949 	if (likely(sk->sk_net_refcnt))
1950 		sock_inuse_add(sock_net(sk), -1);
1951 
1952 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
1953 		sock_diag_broadcast_destroy(sk);
1954 	else
1955 		sk_destruct(sk);
1956 }
1957 
1958 void sk_free(struct sock *sk)
1959 {
1960 	/*
1961 	 * We subtract one from sk_wmem_alloc and can know if
1962 	 * some packets are still in some tx queue.
1963 	 * If not null, sock_wfree() will call __sk_free(sk) later
1964 	 */
1965 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
1966 		__sk_free(sk);
1967 }
1968 EXPORT_SYMBOL(sk_free);
1969 
1970 static void sk_init_common(struct sock *sk)
1971 {
1972 	skb_queue_head_init(&sk->sk_receive_queue);
1973 	skb_queue_head_init(&sk->sk_write_queue);
1974 	skb_queue_head_init(&sk->sk_error_queue);
1975 
1976 	rwlock_init(&sk->sk_callback_lock);
1977 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
1978 			af_rlock_keys + sk->sk_family,
1979 			af_family_rlock_key_strings[sk->sk_family]);
1980 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
1981 			af_wlock_keys + sk->sk_family,
1982 			af_family_wlock_key_strings[sk->sk_family]);
1983 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
1984 			af_elock_keys + sk->sk_family,
1985 			af_family_elock_key_strings[sk->sk_family]);
1986 	lockdep_set_class_and_name(&sk->sk_callback_lock,
1987 			af_callback_keys + sk->sk_family,
1988 			af_family_clock_key_strings[sk->sk_family]);
1989 }
1990 
1991 /**
1992  *	sk_clone_lock - clone a socket, and lock its clone
1993  *	@sk: the socket to clone
1994  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1995  *
1996  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1997  */
1998 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1999 {
2000 	struct proto *prot = READ_ONCE(sk->sk_prot);
2001 	struct sk_filter *filter;
2002 	bool is_charged = true;
2003 	struct sock *newsk;
2004 
2005 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2006 	if (!newsk)
2007 		goto out;
2008 
2009 	sock_copy(newsk, sk);
2010 
2011 	newsk->sk_prot_creator = prot;
2012 
2013 	/* SANITY */
2014 	if (likely(newsk->sk_net_refcnt))
2015 		get_net(sock_net(newsk));
2016 	sk_node_init(&newsk->sk_node);
2017 	sock_lock_init(newsk);
2018 	bh_lock_sock(newsk);
2019 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2020 	newsk->sk_backlog.len = 0;
2021 
2022 	atomic_set(&newsk->sk_rmem_alloc, 0);
2023 
2024 	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2025 	refcount_set(&newsk->sk_wmem_alloc, 1);
2026 
2027 	atomic_set(&newsk->sk_omem_alloc, 0);
2028 	sk_init_common(newsk);
2029 
2030 	newsk->sk_dst_cache	= NULL;
2031 	newsk->sk_dst_pending_confirm = 0;
2032 	newsk->sk_wmem_queued	= 0;
2033 	newsk->sk_forward_alloc = 0;
2034 	atomic_set(&newsk->sk_drops, 0);
2035 	newsk->sk_send_head	= NULL;
2036 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2037 	atomic_set(&newsk->sk_zckey, 0);
2038 
2039 	sock_reset_flag(newsk, SOCK_DONE);
2040 
2041 	/* sk->sk_memcg will be populated at accept() time */
2042 	newsk->sk_memcg = NULL;
2043 
2044 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2045 
2046 	rcu_read_lock();
2047 	filter = rcu_dereference(sk->sk_filter);
2048 	if (filter != NULL)
2049 		/* though it's an empty new sock, the charging may fail
2050 		 * if sysctl_optmem_max was changed between creation of
2051 		 * original socket and cloning
2052 		 */
2053 		is_charged = sk_filter_charge(newsk, filter);
2054 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2055 	rcu_read_unlock();
2056 
2057 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2058 		/* We need to make sure that we don't uncharge the new
2059 		 * socket if we couldn't charge it in the first place
2060 		 * as otherwise we uncharge the parent's filter.
2061 		 */
2062 		if (!is_charged)
2063 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2064 		sk_free_unlock_clone(newsk);
2065 		newsk = NULL;
2066 		goto out;
2067 	}
2068 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2069 
2070 	if (bpf_sk_storage_clone(sk, newsk)) {
2071 		sk_free_unlock_clone(newsk);
2072 		newsk = NULL;
2073 		goto out;
2074 	}
2075 
2076 	/* Clear sk_user_data if parent had the pointer tagged
2077 	 * as not suitable for copying when cloning.
2078 	 */
2079 	if (sk_user_data_is_nocopy(newsk))
2080 		newsk->sk_user_data = NULL;
2081 
2082 	newsk->sk_err	   = 0;
2083 	newsk->sk_err_soft = 0;
2084 	newsk->sk_priority = 0;
2085 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2086 	if (likely(newsk->sk_net_refcnt))
2087 		sock_inuse_add(sock_net(newsk), 1);
2088 
2089 	/* Before updating sk_refcnt, we must commit prior changes to memory
2090 	 * (Documentation/RCU/rculist_nulls.rst for details)
2091 	 */
2092 	smp_wmb();
2093 	refcount_set(&newsk->sk_refcnt, 2);
2094 
2095 	/* Increment the counter in the same struct proto as the master
2096 	 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
2097 	 * is the same as sk->sk_prot->socks, as this field was copied
2098 	 * with memcpy).
2099 	 *
2100 	 * This _changes_ the previous behaviour, where
2101 	 * tcp_create_openreq_child always was incrementing the
2102 	 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
2103 	 * to be taken into account in all callers. -acme
2104 	 */
2105 	sk_refcnt_debug_inc(newsk);
2106 	sk_set_socket(newsk, NULL);
2107 	sk_tx_queue_clear(newsk);
2108 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2109 
2110 	if (newsk->sk_prot->sockets_allocated)
2111 		sk_sockets_allocated_inc(newsk);
2112 
2113 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2114 		net_enable_timestamp();
2115 out:
2116 	return newsk;
2117 }
2118 EXPORT_SYMBOL_GPL(sk_clone_lock);
2119 
2120 void sk_free_unlock_clone(struct sock *sk)
2121 {
2122 	/* It is still raw copy of parent, so invalidate
2123 	 * destructor and make plain sk_free() */
2124 	sk->sk_destruct = NULL;
2125 	bh_unlock_sock(sk);
2126 	sk_free(sk);
2127 }
2128 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2129 
2130 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2131 {
2132 	u32 max_segs = 1;
2133 
2134 	sk_dst_set(sk, dst);
2135 	sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps;
2136 	if (sk->sk_route_caps & NETIF_F_GSO)
2137 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2138 	sk->sk_route_caps &= ~sk->sk_route_nocaps;
2139 	if (sk_can_gso(sk)) {
2140 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2141 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2142 		} else {
2143 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2144 			sk->sk_gso_max_size = dst->dev->gso_max_size;
2145 			max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
2146 		}
2147 	}
2148 	sk->sk_gso_max_segs = max_segs;
2149 }
2150 EXPORT_SYMBOL_GPL(sk_setup_caps);
2151 
2152 /*
2153  *	Simple resource managers for sockets.
2154  */
2155 
2156 
2157 /*
2158  * Write buffer destructor automatically called from kfree_skb.
2159  */
2160 void sock_wfree(struct sk_buff *skb)
2161 {
2162 	struct sock *sk = skb->sk;
2163 	unsigned int len = skb->truesize;
2164 
2165 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2166 		/*
2167 		 * Keep a reference on sk_wmem_alloc, this will be released
2168 		 * after sk_write_space() call
2169 		 */
2170 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2171 		sk->sk_write_space(sk);
2172 		len = 1;
2173 	}
2174 	/*
2175 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2176 	 * could not do because of in-flight packets
2177 	 */
2178 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2179 		__sk_free(sk);
2180 }
2181 EXPORT_SYMBOL(sock_wfree);
2182 
2183 /* This variant of sock_wfree() is used by TCP,
2184  * since it sets SOCK_USE_WRITE_QUEUE.
2185  */
2186 void __sock_wfree(struct sk_buff *skb)
2187 {
2188 	struct sock *sk = skb->sk;
2189 
2190 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2191 		__sk_free(sk);
2192 }
2193 
2194 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2195 {
2196 	skb_orphan(skb);
2197 	skb->sk = sk;
2198 #ifdef CONFIG_INET
2199 	if (unlikely(!sk_fullsock(sk))) {
2200 		skb->destructor = sock_edemux;
2201 		sock_hold(sk);
2202 		return;
2203 	}
2204 #endif
2205 	skb->destructor = sock_wfree;
2206 	skb_set_hash_from_sk(skb, sk);
2207 	/*
2208 	 * We used to take a refcount on sk, but following operation
2209 	 * is enough to guarantee sk_free() wont free this sock until
2210 	 * all in-flight packets are completed
2211 	 */
2212 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2213 }
2214 EXPORT_SYMBOL(skb_set_owner_w);
2215 
2216 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2217 {
2218 #ifdef CONFIG_TLS_DEVICE
2219 	/* Drivers depend on in-order delivery for crypto offload,
2220 	 * partial orphan breaks out-of-order-OK logic.
2221 	 */
2222 	if (skb->decrypted)
2223 		return false;
2224 #endif
2225 	return (skb->destructor == sock_wfree ||
2226 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2227 }
2228 
2229 /* This helper is used by netem, as it can hold packets in its
2230  * delay queue. We want to allow the owner socket to send more
2231  * packets, as if they were already TX completed by a typical driver.
2232  * But we also want to keep skb->sk set because some packet schedulers
2233  * rely on it (sch_fq for example).
2234  */
2235 void skb_orphan_partial(struct sk_buff *skb)
2236 {
2237 	if (skb_is_tcp_pure_ack(skb))
2238 		return;
2239 
2240 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2241 		return;
2242 
2243 	skb_orphan(skb);
2244 }
2245 EXPORT_SYMBOL(skb_orphan_partial);
2246 
2247 /*
2248  * Read buffer destructor automatically called from kfree_skb.
2249  */
2250 void sock_rfree(struct sk_buff *skb)
2251 {
2252 	struct sock *sk = skb->sk;
2253 	unsigned int len = skb->truesize;
2254 
2255 	atomic_sub(len, &sk->sk_rmem_alloc);
2256 	sk_mem_uncharge(sk, len);
2257 }
2258 EXPORT_SYMBOL(sock_rfree);
2259 
2260 /*
2261  * Buffer destructor for skbs that are not used directly in read or write
2262  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2263  */
2264 void sock_efree(struct sk_buff *skb)
2265 {
2266 	sock_put(skb->sk);
2267 }
2268 EXPORT_SYMBOL(sock_efree);
2269 
2270 /* Buffer destructor for prefetch/receive path where reference count may
2271  * not be held, e.g. for listen sockets.
2272  */
2273 #ifdef CONFIG_INET
2274 void sock_pfree(struct sk_buff *skb)
2275 {
2276 	if (sk_is_refcounted(skb->sk))
2277 		sock_gen_put(skb->sk);
2278 }
2279 EXPORT_SYMBOL(sock_pfree);
2280 #endif /* CONFIG_INET */
2281 
2282 kuid_t sock_i_uid(struct sock *sk)
2283 {
2284 	kuid_t uid;
2285 
2286 	read_lock_bh(&sk->sk_callback_lock);
2287 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2288 	read_unlock_bh(&sk->sk_callback_lock);
2289 	return uid;
2290 }
2291 EXPORT_SYMBOL(sock_i_uid);
2292 
2293 unsigned long sock_i_ino(struct sock *sk)
2294 {
2295 	unsigned long ino;
2296 
2297 	read_lock_bh(&sk->sk_callback_lock);
2298 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2299 	read_unlock_bh(&sk->sk_callback_lock);
2300 	return ino;
2301 }
2302 EXPORT_SYMBOL(sock_i_ino);
2303 
2304 /*
2305  * Allocate a skb from the socket's send buffer.
2306  */
2307 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2308 			     gfp_t priority)
2309 {
2310 	if (force ||
2311 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2312 		struct sk_buff *skb = alloc_skb(size, priority);
2313 
2314 		if (skb) {
2315 			skb_set_owner_w(skb, sk);
2316 			return skb;
2317 		}
2318 	}
2319 	return NULL;
2320 }
2321 EXPORT_SYMBOL(sock_wmalloc);
2322 
2323 static void sock_ofree(struct sk_buff *skb)
2324 {
2325 	struct sock *sk = skb->sk;
2326 
2327 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2328 }
2329 
2330 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2331 			     gfp_t priority)
2332 {
2333 	struct sk_buff *skb;
2334 
2335 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2336 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2337 	    sysctl_optmem_max)
2338 		return NULL;
2339 
2340 	skb = alloc_skb(size, priority);
2341 	if (!skb)
2342 		return NULL;
2343 
2344 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2345 	skb->sk = sk;
2346 	skb->destructor = sock_ofree;
2347 	return skb;
2348 }
2349 
2350 /*
2351  * Allocate a memory block from the socket's option memory buffer.
2352  */
2353 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2354 {
2355 	if ((unsigned int)size <= sysctl_optmem_max &&
2356 	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
2357 		void *mem;
2358 		/* First do the add, to avoid the race if kmalloc
2359 		 * might sleep.
2360 		 */
2361 		atomic_add(size, &sk->sk_omem_alloc);
2362 		mem = kmalloc(size, priority);
2363 		if (mem)
2364 			return mem;
2365 		atomic_sub(size, &sk->sk_omem_alloc);
2366 	}
2367 	return NULL;
2368 }
2369 EXPORT_SYMBOL(sock_kmalloc);
2370 
2371 /* Free an option memory block. Note, we actually want the inline
2372  * here as this allows gcc to detect the nullify and fold away the
2373  * condition entirely.
2374  */
2375 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2376 				  const bool nullify)
2377 {
2378 	if (WARN_ON_ONCE(!mem))
2379 		return;
2380 	if (nullify)
2381 		kfree_sensitive(mem);
2382 	else
2383 		kfree(mem);
2384 	atomic_sub(size, &sk->sk_omem_alloc);
2385 }
2386 
2387 void sock_kfree_s(struct sock *sk, void *mem, int size)
2388 {
2389 	__sock_kfree_s(sk, mem, size, false);
2390 }
2391 EXPORT_SYMBOL(sock_kfree_s);
2392 
2393 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2394 {
2395 	__sock_kfree_s(sk, mem, size, true);
2396 }
2397 EXPORT_SYMBOL(sock_kzfree_s);
2398 
2399 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2400    I think, these locks should be removed for datagram sockets.
2401  */
2402 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2403 {
2404 	DEFINE_WAIT(wait);
2405 
2406 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2407 	for (;;) {
2408 		if (!timeo)
2409 			break;
2410 		if (signal_pending(current))
2411 			break;
2412 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2413 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2414 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2415 			break;
2416 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2417 			break;
2418 		if (sk->sk_err)
2419 			break;
2420 		timeo = schedule_timeout(timeo);
2421 	}
2422 	finish_wait(sk_sleep(sk), &wait);
2423 	return timeo;
2424 }
2425 
2426 
2427 /*
2428  *	Generic send/receive buffer handlers
2429  */
2430 
2431 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2432 				     unsigned long data_len, int noblock,
2433 				     int *errcode, int max_page_order)
2434 {
2435 	struct sk_buff *skb;
2436 	long timeo;
2437 	int err;
2438 
2439 	timeo = sock_sndtimeo(sk, noblock);
2440 	for (;;) {
2441 		err = sock_error(sk);
2442 		if (err != 0)
2443 			goto failure;
2444 
2445 		err = -EPIPE;
2446 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2447 			goto failure;
2448 
2449 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2450 			break;
2451 
2452 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2453 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2454 		err = -EAGAIN;
2455 		if (!timeo)
2456 			goto failure;
2457 		if (signal_pending(current))
2458 			goto interrupted;
2459 		timeo = sock_wait_for_wmem(sk, timeo);
2460 	}
2461 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2462 				   errcode, sk->sk_allocation);
2463 	if (skb)
2464 		skb_set_owner_w(skb, sk);
2465 	return skb;
2466 
2467 interrupted:
2468 	err = sock_intr_errno(timeo);
2469 failure:
2470 	*errcode = err;
2471 	return NULL;
2472 }
2473 EXPORT_SYMBOL(sock_alloc_send_pskb);
2474 
2475 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2476 				    int noblock, int *errcode)
2477 {
2478 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2479 }
2480 EXPORT_SYMBOL(sock_alloc_send_skb);
2481 
2482 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2483 		     struct sockcm_cookie *sockc)
2484 {
2485 	u32 tsflags;
2486 
2487 	switch (cmsg->cmsg_type) {
2488 	case SO_MARK:
2489 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2490 			return -EPERM;
2491 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2492 			return -EINVAL;
2493 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2494 		break;
2495 	case SO_TIMESTAMPING_OLD:
2496 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2497 			return -EINVAL;
2498 
2499 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2500 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2501 			return -EINVAL;
2502 
2503 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2504 		sockc->tsflags |= tsflags;
2505 		break;
2506 	case SCM_TXTIME:
2507 		if (!sock_flag(sk, SOCK_TXTIME))
2508 			return -EINVAL;
2509 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2510 			return -EINVAL;
2511 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2512 		break;
2513 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2514 	case SCM_RIGHTS:
2515 	case SCM_CREDENTIALS:
2516 		break;
2517 	default:
2518 		return -EINVAL;
2519 	}
2520 	return 0;
2521 }
2522 EXPORT_SYMBOL(__sock_cmsg_send);
2523 
2524 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2525 		   struct sockcm_cookie *sockc)
2526 {
2527 	struct cmsghdr *cmsg;
2528 	int ret;
2529 
2530 	for_each_cmsghdr(cmsg, msg) {
2531 		if (!CMSG_OK(msg, cmsg))
2532 			return -EINVAL;
2533 		if (cmsg->cmsg_level != SOL_SOCKET)
2534 			continue;
2535 		ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2536 		if (ret)
2537 			return ret;
2538 	}
2539 	return 0;
2540 }
2541 EXPORT_SYMBOL(sock_cmsg_send);
2542 
2543 static void sk_enter_memory_pressure(struct sock *sk)
2544 {
2545 	if (!sk->sk_prot->enter_memory_pressure)
2546 		return;
2547 
2548 	sk->sk_prot->enter_memory_pressure(sk);
2549 }
2550 
2551 static void sk_leave_memory_pressure(struct sock *sk)
2552 {
2553 	if (sk->sk_prot->leave_memory_pressure) {
2554 		sk->sk_prot->leave_memory_pressure(sk);
2555 	} else {
2556 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2557 
2558 		if (memory_pressure && READ_ONCE(*memory_pressure))
2559 			WRITE_ONCE(*memory_pressure, 0);
2560 	}
2561 }
2562 
2563 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2564 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2565 
2566 /**
2567  * skb_page_frag_refill - check that a page_frag contains enough room
2568  * @sz: minimum size of the fragment we want to get
2569  * @pfrag: pointer to page_frag
2570  * @gfp: priority for memory allocation
2571  *
2572  * Note: While this allocator tries to use high order pages, there is
2573  * no guarantee that allocations succeed. Therefore, @sz MUST be
2574  * less or equal than PAGE_SIZE.
2575  */
2576 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2577 {
2578 	if (pfrag->page) {
2579 		if (page_ref_count(pfrag->page) == 1) {
2580 			pfrag->offset = 0;
2581 			return true;
2582 		}
2583 		if (pfrag->offset + sz <= pfrag->size)
2584 			return true;
2585 		put_page(pfrag->page);
2586 	}
2587 
2588 	pfrag->offset = 0;
2589 	if (SKB_FRAG_PAGE_ORDER &&
2590 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2591 		/* Avoid direct reclaim but allow kswapd to wake */
2592 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2593 					  __GFP_COMP | __GFP_NOWARN |
2594 					  __GFP_NORETRY,
2595 					  SKB_FRAG_PAGE_ORDER);
2596 		if (likely(pfrag->page)) {
2597 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2598 			return true;
2599 		}
2600 	}
2601 	pfrag->page = alloc_page(gfp);
2602 	if (likely(pfrag->page)) {
2603 		pfrag->size = PAGE_SIZE;
2604 		return true;
2605 	}
2606 	return false;
2607 }
2608 EXPORT_SYMBOL(skb_page_frag_refill);
2609 
2610 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2611 {
2612 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2613 		return true;
2614 
2615 	sk_enter_memory_pressure(sk);
2616 	sk_stream_moderate_sndbuf(sk);
2617 	return false;
2618 }
2619 EXPORT_SYMBOL(sk_page_frag_refill);
2620 
2621 void __lock_sock(struct sock *sk)
2622 	__releases(&sk->sk_lock.slock)
2623 	__acquires(&sk->sk_lock.slock)
2624 {
2625 	DEFINE_WAIT(wait);
2626 
2627 	for (;;) {
2628 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2629 					TASK_UNINTERRUPTIBLE);
2630 		spin_unlock_bh(&sk->sk_lock.slock);
2631 		schedule();
2632 		spin_lock_bh(&sk->sk_lock.slock);
2633 		if (!sock_owned_by_user(sk))
2634 			break;
2635 	}
2636 	finish_wait(&sk->sk_lock.wq, &wait);
2637 }
2638 
2639 void __release_sock(struct sock *sk)
2640 	__releases(&sk->sk_lock.slock)
2641 	__acquires(&sk->sk_lock.slock)
2642 {
2643 	struct sk_buff *skb, *next;
2644 
2645 	while ((skb = sk->sk_backlog.head) != NULL) {
2646 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2647 
2648 		spin_unlock_bh(&sk->sk_lock.slock);
2649 
2650 		do {
2651 			next = skb->next;
2652 			prefetch(next);
2653 			WARN_ON_ONCE(skb_dst_is_noref(skb));
2654 			skb_mark_not_on_list(skb);
2655 			sk_backlog_rcv(sk, skb);
2656 
2657 			cond_resched();
2658 
2659 			skb = next;
2660 		} while (skb != NULL);
2661 
2662 		spin_lock_bh(&sk->sk_lock.slock);
2663 	}
2664 
2665 	/*
2666 	 * Doing the zeroing here guarantee we can not loop forever
2667 	 * while a wild producer attempts to flood us.
2668 	 */
2669 	sk->sk_backlog.len = 0;
2670 }
2671 
2672 void __sk_flush_backlog(struct sock *sk)
2673 {
2674 	spin_lock_bh(&sk->sk_lock.slock);
2675 	__release_sock(sk);
2676 	spin_unlock_bh(&sk->sk_lock.slock);
2677 }
2678 
2679 /**
2680  * sk_wait_data - wait for data to arrive at sk_receive_queue
2681  * @sk:    sock to wait on
2682  * @timeo: for how long
2683  * @skb:   last skb seen on sk_receive_queue
2684  *
2685  * Now socket state including sk->sk_err is changed only under lock,
2686  * hence we may omit checks after joining wait queue.
2687  * We check receive queue before schedule() only as optimization;
2688  * it is very likely that release_sock() added new data.
2689  */
2690 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2691 {
2692 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2693 	int rc;
2694 
2695 	add_wait_queue(sk_sleep(sk), &wait);
2696 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2697 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2698 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2699 	remove_wait_queue(sk_sleep(sk), &wait);
2700 	return rc;
2701 }
2702 EXPORT_SYMBOL(sk_wait_data);
2703 
2704 /**
2705  *	__sk_mem_raise_allocated - increase memory_allocated
2706  *	@sk: socket
2707  *	@size: memory size to allocate
2708  *	@amt: pages to allocate
2709  *	@kind: allocation type
2710  *
2711  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2712  */
2713 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2714 {
2715 	struct proto *prot = sk->sk_prot;
2716 	long allocated = sk_memory_allocated_add(sk, amt);
2717 	bool charged = true;
2718 
2719 	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2720 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt)))
2721 		goto suppress_allocation;
2722 
2723 	/* Under limit. */
2724 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2725 		sk_leave_memory_pressure(sk);
2726 		return 1;
2727 	}
2728 
2729 	/* Under pressure. */
2730 	if (allocated > sk_prot_mem_limits(sk, 1))
2731 		sk_enter_memory_pressure(sk);
2732 
2733 	/* Over hard limit. */
2734 	if (allocated > sk_prot_mem_limits(sk, 2))
2735 		goto suppress_allocation;
2736 
2737 	/* guarantee minimum buffer size under pressure */
2738 	if (kind == SK_MEM_RECV) {
2739 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2740 			return 1;
2741 
2742 	} else { /* SK_MEM_SEND */
2743 		int wmem0 = sk_get_wmem0(sk, prot);
2744 
2745 		if (sk->sk_type == SOCK_STREAM) {
2746 			if (sk->sk_wmem_queued < wmem0)
2747 				return 1;
2748 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
2749 				return 1;
2750 		}
2751 	}
2752 
2753 	if (sk_has_memory_pressure(sk)) {
2754 		u64 alloc;
2755 
2756 		if (!sk_under_memory_pressure(sk))
2757 			return 1;
2758 		alloc = sk_sockets_allocated_read_positive(sk);
2759 		if (sk_prot_mem_limits(sk, 2) > alloc *
2760 		    sk_mem_pages(sk->sk_wmem_queued +
2761 				 atomic_read(&sk->sk_rmem_alloc) +
2762 				 sk->sk_forward_alloc))
2763 			return 1;
2764 	}
2765 
2766 suppress_allocation:
2767 
2768 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2769 		sk_stream_moderate_sndbuf(sk);
2770 
2771 		/* Fail only if socket is _under_ its sndbuf.
2772 		 * In this case we cannot block, so that we have to fail.
2773 		 */
2774 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2775 			return 1;
2776 	}
2777 
2778 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
2779 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
2780 
2781 	sk_memory_allocated_sub(sk, amt);
2782 
2783 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2784 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2785 
2786 	return 0;
2787 }
2788 EXPORT_SYMBOL(__sk_mem_raise_allocated);
2789 
2790 /**
2791  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2792  *	@sk: socket
2793  *	@size: memory size to allocate
2794  *	@kind: allocation type
2795  *
2796  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2797  *	rmem allocation. This function assumes that protocols which have
2798  *	memory_pressure use sk_wmem_queued as write buffer accounting.
2799  */
2800 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2801 {
2802 	int ret, amt = sk_mem_pages(size);
2803 
2804 	sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2805 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2806 	if (!ret)
2807 		sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2808 	return ret;
2809 }
2810 EXPORT_SYMBOL(__sk_mem_schedule);
2811 
2812 /**
2813  *	__sk_mem_reduce_allocated - reclaim memory_allocated
2814  *	@sk: socket
2815  *	@amount: number of quanta
2816  *
2817  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2818  */
2819 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2820 {
2821 	sk_memory_allocated_sub(sk, amount);
2822 
2823 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2824 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2825 
2826 	if (sk_under_memory_pressure(sk) &&
2827 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2828 		sk_leave_memory_pressure(sk);
2829 }
2830 EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2831 
2832 /**
2833  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2834  *	@sk: socket
2835  *	@amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2836  */
2837 void __sk_mem_reclaim(struct sock *sk, int amount)
2838 {
2839 	amount >>= SK_MEM_QUANTUM_SHIFT;
2840 	sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2841 	__sk_mem_reduce_allocated(sk, amount);
2842 }
2843 EXPORT_SYMBOL(__sk_mem_reclaim);
2844 
2845 int sk_set_peek_off(struct sock *sk, int val)
2846 {
2847 	sk->sk_peek_off = val;
2848 	return 0;
2849 }
2850 EXPORT_SYMBOL_GPL(sk_set_peek_off);
2851 
2852 /*
2853  * Set of default routines for initialising struct proto_ops when
2854  * the protocol does not support a particular function. In certain
2855  * cases where it makes no sense for a protocol to have a "do nothing"
2856  * function, some default processing is provided.
2857  */
2858 
2859 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2860 {
2861 	return -EOPNOTSUPP;
2862 }
2863 EXPORT_SYMBOL(sock_no_bind);
2864 
2865 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2866 		    int len, int flags)
2867 {
2868 	return -EOPNOTSUPP;
2869 }
2870 EXPORT_SYMBOL(sock_no_connect);
2871 
2872 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2873 {
2874 	return -EOPNOTSUPP;
2875 }
2876 EXPORT_SYMBOL(sock_no_socketpair);
2877 
2878 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2879 		   bool kern)
2880 {
2881 	return -EOPNOTSUPP;
2882 }
2883 EXPORT_SYMBOL(sock_no_accept);
2884 
2885 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2886 		    int peer)
2887 {
2888 	return -EOPNOTSUPP;
2889 }
2890 EXPORT_SYMBOL(sock_no_getname);
2891 
2892 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2893 {
2894 	return -EOPNOTSUPP;
2895 }
2896 EXPORT_SYMBOL(sock_no_ioctl);
2897 
2898 int sock_no_listen(struct socket *sock, int backlog)
2899 {
2900 	return -EOPNOTSUPP;
2901 }
2902 EXPORT_SYMBOL(sock_no_listen);
2903 
2904 int sock_no_shutdown(struct socket *sock, int how)
2905 {
2906 	return -EOPNOTSUPP;
2907 }
2908 EXPORT_SYMBOL(sock_no_shutdown);
2909 
2910 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2911 {
2912 	return -EOPNOTSUPP;
2913 }
2914 EXPORT_SYMBOL(sock_no_sendmsg);
2915 
2916 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
2917 {
2918 	return -EOPNOTSUPP;
2919 }
2920 EXPORT_SYMBOL(sock_no_sendmsg_locked);
2921 
2922 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2923 		    int flags)
2924 {
2925 	return -EOPNOTSUPP;
2926 }
2927 EXPORT_SYMBOL(sock_no_recvmsg);
2928 
2929 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2930 {
2931 	/* Mirror missing mmap method error code */
2932 	return -ENODEV;
2933 }
2934 EXPORT_SYMBOL(sock_no_mmap);
2935 
2936 /*
2937  * When a file is received (via SCM_RIGHTS, etc), we must bump the
2938  * various sock-based usage counts.
2939  */
2940 void __receive_sock(struct file *file)
2941 {
2942 	struct socket *sock;
2943 
2944 	sock = sock_from_file(file);
2945 	if (sock) {
2946 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
2947 		sock_update_classid(&sock->sk->sk_cgrp_data);
2948 	}
2949 }
2950 
2951 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2952 {
2953 	ssize_t res;
2954 	struct msghdr msg = {.msg_flags = flags};
2955 	struct kvec iov;
2956 	char *kaddr = kmap(page);
2957 	iov.iov_base = kaddr + offset;
2958 	iov.iov_len = size;
2959 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2960 	kunmap(page);
2961 	return res;
2962 }
2963 EXPORT_SYMBOL(sock_no_sendpage);
2964 
2965 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
2966 				int offset, size_t size, int flags)
2967 {
2968 	ssize_t res;
2969 	struct msghdr msg = {.msg_flags = flags};
2970 	struct kvec iov;
2971 	char *kaddr = kmap(page);
2972 
2973 	iov.iov_base = kaddr + offset;
2974 	iov.iov_len = size;
2975 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
2976 	kunmap(page);
2977 	return res;
2978 }
2979 EXPORT_SYMBOL(sock_no_sendpage_locked);
2980 
2981 /*
2982  *	Default Socket Callbacks
2983  */
2984 
2985 static void sock_def_wakeup(struct sock *sk)
2986 {
2987 	struct socket_wq *wq;
2988 
2989 	rcu_read_lock();
2990 	wq = rcu_dereference(sk->sk_wq);
2991 	if (skwq_has_sleeper(wq))
2992 		wake_up_interruptible_all(&wq->wait);
2993 	rcu_read_unlock();
2994 }
2995 
2996 static void sock_def_error_report(struct sock *sk)
2997 {
2998 	struct socket_wq *wq;
2999 
3000 	rcu_read_lock();
3001 	wq = rcu_dereference(sk->sk_wq);
3002 	if (skwq_has_sleeper(wq))
3003 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3004 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3005 	rcu_read_unlock();
3006 }
3007 
3008 void sock_def_readable(struct sock *sk)
3009 {
3010 	struct socket_wq *wq;
3011 
3012 	rcu_read_lock();
3013 	wq = rcu_dereference(sk->sk_wq);
3014 	if (skwq_has_sleeper(wq))
3015 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3016 						EPOLLRDNORM | EPOLLRDBAND);
3017 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3018 	rcu_read_unlock();
3019 }
3020 
3021 static void sock_def_write_space(struct sock *sk)
3022 {
3023 	struct socket_wq *wq;
3024 
3025 	rcu_read_lock();
3026 
3027 	/* Do not wake up a writer until he can make "significant"
3028 	 * progress.  --DaveM
3029 	 */
3030 	if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= READ_ONCE(sk->sk_sndbuf)) {
3031 		wq = rcu_dereference(sk->sk_wq);
3032 		if (skwq_has_sleeper(wq))
3033 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3034 						EPOLLWRNORM | EPOLLWRBAND);
3035 
3036 		/* Should agree with poll, otherwise some programs break */
3037 		if (sock_writeable(sk))
3038 			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3039 	}
3040 
3041 	rcu_read_unlock();
3042 }
3043 
3044 static void sock_def_destruct(struct sock *sk)
3045 {
3046 }
3047 
3048 void sk_send_sigurg(struct sock *sk)
3049 {
3050 	if (sk->sk_socket && sk->sk_socket->file)
3051 		if (send_sigurg(&sk->sk_socket->file->f_owner))
3052 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3053 }
3054 EXPORT_SYMBOL(sk_send_sigurg);
3055 
3056 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3057 		    unsigned long expires)
3058 {
3059 	if (!mod_timer(timer, expires))
3060 		sock_hold(sk);
3061 }
3062 EXPORT_SYMBOL(sk_reset_timer);
3063 
3064 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3065 {
3066 	if (del_timer(timer))
3067 		__sock_put(sk);
3068 }
3069 EXPORT_SYMBOL(sk_stop_timer);
3070 
3071 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3072 {
3073 	if (del_timer_sync(timer))
3074 		__sock_put(sk);
3075 }
3076 EXPORT_SYMBOL(sk_stop_timer_sync);
3077 
3078 void sock_init_data(struct socket *sock, struct sock *sk)
3079 {
3080 	sk_init_common(sk);
3081 	sk->sk_send_head	=	NULL;
3082 
3083 	timer_setup(&sk->sk_timer, NULL, 0);
3084 
3085 	sk->sk_allocation	=	GFP_KERNEL;
3086 	sk->sk_rcvbuf		=	sysctl_rmem_default;
3087 	sk->sk_sndbuf		=	sysctl_wmem_default;
3088 	sk->sk_state		=	TCP_CLOSE;
3089 	sk_set_socket(sk, sock);
3090 
3091 	sock_set_flag(sk, SOCK_ZAPPED);
3092 
3093 	if (sock) {
3094 		sk->sk_type	=	sock->type;
3095 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3096 		sock->sk	=	sk;
3097 		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
3098 	} else {
3099 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3100 		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
3101 	}
3102 
3103 	rwlock_init(&sk->sk_callback_lock);
3104 	if (sk->sk_kern_sock)
3105 		lockdep_set_class_and_name(
3106 			&sk->sk_callback_lock,
3107 			af_kern_callback_keys + sk->sk_family,
3108 			af_family_kern_clock_key_strings[sk->sk_family]);
3109 	else
3110 		lockdep_set_class_and_name(
3111 			&sk->sk_callback_lock,
3112 			af_callback_keys + sk->sk_family,
3113 			af_family_clock_key_strings[sk->sk_family]);
3114 
3115 	sk->sk_state_change	=	sock_def_wakeup;
3116 	sk->sk_data_ready	=	sock_def_readable;
3117 	sk->sk_write_space	=	sock_def_write_space;
3118 	sk->sk_error_report	=	sock_def_error_report;
3119 	sk->sk_destruct		=	sock_def_destruct;
3120 
3121 	sk->sk_frag.page	=	NULL;
3122 	sk->sk_frag.offset	=	0;
3123 	sk->sk_peek_off		=	-1;
3124 
3125 	sk->sk_peer_pid 	=	NULL;
3126 	sk->sk_peer_cred	=	NULL;
3127 	sk->sk_write_pending	=	0;
3128 	sk->sk_rcvlowat		=	1;
3129 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3130 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3131 
3132 	sk->sk_stamp = SK_DEFAULT_STAMP;
3133 #if BITS_PER_LONG==32
3134 	seqlock_init(&sk->sk_stamp_seq);
3135 #endif
3136 	atomic_set(&sk->sk_zckey, 0);
3137 
3138 #ifdef CONFIG_NET_RX_BUSY_POLL
3139 	sk->sk_napi_id		=	0;
3140 	sk->sk_ll_usec		=	sysctl_net_busy_read;
3141 #endif
3142 
3143 	sk->sk_max_pacing_rate = ~0UL;
3144 	sk->sk_pacing_rate = ~0UL;
3145 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3146 	sk->sk_incoming_cpu = -1;
3147 
3148 	sk_rx_queue_clear(sk);
3149 	/*
3150 	 * Before updating sk_refcnt, we must commit prior changes to memory
3151 	 * (Documentation/RCU/rculist_nulls.rst for details)
3152 	 */
3153 	smp_wmb();
3154 	refcount_set(&sk->sk_refcnt, 1);
3155 	atomic_set(&sk->sk_drops, 0);
3156 }
3157 EXPORT_SYMBOL(sock_init_data);
3158 
3159 void lock_sock_nested(struct sock *sk, int subclass)
3160 {
3161 	might_sleep();
3162 	spin_lock_bh(&sk->sk_lock.slock);
3163 	if (sk->sk_lock.owned)
3164 		__lock_sock(sk);
3165 	sk->sk_lock.owned = 1;
3166 	spin_unlock(&sk->sk_lock.slock);
3167 	/*
3168 	 * The sk_lock has mutex_lock() semantics here:
3169 	 */
3170 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3171 	local_bh_enable();
3172 }
3173 EXPORT_SYMBOL(lock_sock_nested);
3174 
3175 void release_sock(struct sock *sk)
3176 {
3177 	spin_lock_bh(&sk->sk_lock.slock);
3178 	if (sk->sk_backlog.tail)
3179 		__release_sock(sk);
3180 
3181 	/* Warning : release_cb() might need to release sk ownership,
3182 	 * ie call sock_release_ownership(sk) before us.
3183 	 */
3184 	if (sk->sk_prot->release_cb)
3185 		sk->sk_prot->release_cb(sk);
3186 
3187 	sock_release_ownership(sk);
3188 	if (waitqueue_active(&sk->sk_lock.wq))
3189 		wake_up(&sk->sk_lock.wq);
3190 	spin_unlock_bh(&sk->sk_lock.slock);
3191 }
3192 EXPORT_SYMBOL(release_sock);
3193 
3194 /**
3195  * lock_sock_fast - fast version of lock_sock
3196  * @sk: socket
3197  *
3198  * This version should be used for very small section, where process wont block
3199  * return false if fast path is taken:
3200  *
3201  *   sk_lock.slock locked, owned = 0, BH disabled
3202  *
3203  * return true if slow path is taken:
3204  *
3205  *   sk_lock.slock unlocked, owned = 1, BH enabled
3206  */
3207 bool lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3208 {
3209 	might_sleep();
3210 	spin_lock_bh(&sk->sk_lock.slock);
3211 
3212 	if (!sk->sk_lock.owned)
3213 		/*
3214 		 * Note : We must disable BH
3215 		 */
3216 		return false;
3217 
3218 	__lock_sock(sk);
3219 	sk->sk_lock.owned = 1;
3220 	spin_unlock(&sk->sk_lock.slock);
3221 	/*
3222 	 * The sk_lock has mutex_lock() semantics here:
3223 	 */
3224 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
3225 	__acquire(&sk->sk_lock.slock);
3226 	local_bh_enable();
3227 	return true;
3228 }
3229 EXPORT_SYMBOL(lock_sock_fast);
3230 
3231 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3232 		   bool timeval, bool time32)
3233 {
3234 	struct sock *sk = sock->sk;
3235 	struct timespec64 ts;
3236 
3237 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3238 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3239 	if (ts.tv_sec == -1)
3240 		return -ENOENT;
3241 	if (ts.tv_sec == 0) {
3242 		ktime_t kt = ktime_get_real();
3243 		sock_write_timestamp(sk, kt);
3244 		ts = ktime_to_timespec64(kt);
3245 	}
3246 
3247 	if (timeval)
3248 		ts.tv_nsec /= 1000;
3249 
3250 #ifdef CONFIG_COMPAT_32BIT_TIME
3251 	if (time32)
3252 		return put_old_timespec32(&ts, userstamp);
3253 #endif
3254 #ifdef CONFIG_SPARC64
3255 	/* beware of padding in sparc64 timeval */
3256 	if (timeval && !in_compat_syscall()) {
3257 		struct __kernel_old_timeval __user tv = {
3258 			.tv_sec = ts.tv_sec,
3259 			.tv_usec = ts.tv_nsec,
3260 		};
3261 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3262 			return -EFAULT;
3263 		return 0;
3264 	}
3265 #endif
3266 	return put_timespec64(&ts, userstamp);
3267 }
3268 EXPORT_SYMBOL(sock_gettstamp);
3269 
3270 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3271 {
3272 	if (!sock_flag(sk, flag)) {
3273 		unsigned long previous_flags = sk->sk_flags;
3274 
3275 		sock_set_flag(sk, flag);
3276 		/*
3277 		 * we just set one of the two flags which require net
3278 		 * time stamping, but time stamping might have been on
3279 		 * already because of the other one
3280 		 */
3281 		if (sock_needs_netstamp(sk) &&
3282 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3283 			net_enable_timestamp();
3284 	}
3285 }
3286 
3287 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3288 		       int level, int type)
3289 {
3290 	struct sock_exterr_skb *serr;
3291 	struct sk_buff *skb;
3292 	int copied, err;
3293 
3294 	err = -EAGAIN;
3295 	skb = sock_dequeue_err_skb(sk);
3296 	if (skb == NULL)
3297 		goto out;
3298 
3299 	copied = skb->len;
3300 	if (copied > len) {
3301 		msg->msg_flags |= MSG_TRUNC;
3302 		copied = len;
3303 	}
3304 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3305 	if (err)
3306 		goto out_free_skb;
3307 
3308 	sock_recv_timestamp(msg, sk, skb);
3309 
3310 	serr = SKB_EXT_ERR(skb);
3311 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3312 
3313 	msg->msg_flags |= MSG_ERRQUEUE;
3314 	err = copied;
3315 
3316 out_free_skb:
3317 	kfree_skb(skb);
3318 out:
3319 	return err;
3320 }
3321 EXPORT_SYMBOL(sock_recv_errqueue);
3322 
3323 /*
3324  *	Get a socket option on an socket.
3325  *
3326  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3327  *	asynchronous errors should be reported by getsockopt. We assume
3328  *	this means if you specify SO_ERROR (otherwise whats the point of it).
3329  */
3330 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3331 			   char __user *optval, int __user *optlen)
3332 {
3333 	struct sock *sk = sock->sk;
3334 
3335 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3336 }
3337 EXPORT_SYMBOL(sock_common_getsockopt);
3338 
3339 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3340 			int flags)
3341 {
3342 	struct sock *sk = sock->sk;
3343 	int addr_len = 0;
3344 	int err;
3345 
3346 	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
3347 				   flags & ~MSG_DONTWAIT, &addr_len);
3348 	if (err >= 0)
3349 		msg->msg_namelen = addr_len;
3350 	return err;
3351 }
3352 EXPORT_SYMBOL(sock_common_recvmsg);
3353 
3354 /*
3355  *	Set socket options on an inet socket.
3356  */
3357 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3358 			   sockptr_t optval, unsigned int optlen)
3359 {
3360 	struct sock *sk = sock->sk;
3361 
3362 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3363 }
3364 EXPORT_SYMBOL(sock_common_setsockopt);
3365 
3366 void sk_common_release(struct sock *sk)
3367 {
3368 	if (sk->sk_prot->destroy)
3369 		sk->sk_prot->destroy(sk);
3370 
3371 	/*
3372 	 * Observation: when sk_common_release is called, processes have
3373 	 * no access to socket. But net still has.
3374 	 * Step one, detach it from networking:
3375 	 *
3376 	 * A. Remove from hash tables.
3377 	 */
3378 
3379 	sk->sk_prot->unhash(sk);
3380 
3381 	/*
3382 	 * In this point socket cannot receive new packets, but it is possible
3383 	 * that some packets are in flight because some CPU runs receiver and
3384 	 * did hash table lookup before we unhashed socket. They will achieve
3385 	 * receive queue and will be purged by socket destructor.
3386 	 *
3387 	 * Also we still have packets pending on receive queue and probably,
3388 	 * our own packets waiting in device queues. sock_destroy will drain
3389 	 * receive queue, but transmitted packets will delay socket destruction
3390 	 * until the last reference will be released.
3391 	 */
3392 
3393 	sock_orphan(sk);
3394 
3395 	xfrm_sk_free_policy(sk);
3396 
3397 	sk_refcnt_debug_release(sk);
3398 
3399 	sock_put(sk);
3400 }
3401 EXPORT_SYMBOL(sk_common_release);
3402 
3403 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3404 {
3405 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3406 
3407 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3408 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3409 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3410 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3411 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3412 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3413 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3414 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3415 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3416 }
3417 
3418 #ifdef CONFIG_PROC_FS
3419 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
3420 struct prot_inuse {
3421 	int val[PROTO_INUSE_NR];
3422 };
3423 
3424 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3425 
3426 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3427 {
3428 	__this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
3429 }
3430 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3431 
3432 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3433 {
3434 	int cpu, idx = prot->inuse_idx;
3435 	int res = 0;
3436 
3437 	for_each_possible_cpu(cpu)
3438 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3439 
3440 	return res >= 0 ? res : 0;
3441 }
3442 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3443 
3444 static void sock_inuse_add(struct net *net, int val)
3445 {
3446 	this_cpu_add(*net->core.sock_inuse, val);
3447 }
3448 
3449 int sock_inuse_get(struct net *net)
3450 {
3451 	int cpu, res = 0;
3452 
3453 	for_each_possible_cpu(cpu)
3454 		res += *per_cpu_ptr(net->core.sock_inuse, cpu);
3455 
3456 	return res;
3457 }
3458 
3459 EXPORT_SYMBOL_GPL(sock_inuse_get);
3460 
3461 static int __net_init sock_inuse_init_net(struct net *net)
3462 {
3463 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3464 	if (net->core.prot_inuse == NULL)
3465 		return -ENOMEM;
3466 
3467 	net->core.sock_inuse = alloc_percpu(int);
3468 	if (net->core.sock_inuse == NULL)
3469 		goto out;
3470 
3471 	return 0;
3472 
3473 out:
3474 	free_percpu(net->core.prot_inuse);
3475 	return -ENOMEM;
3476 }
3477 
3478 static void __net_exit sock_inuse_exit_net(struct net *net)
3479 {
3480 	free_percpu(net->core.prot_inuse);
3481 	free_percpu(net->core.sock_inuse);
3482 }
3483 
3484 static struct pernet_operations net_inuse_ops = {
3485 	.init = sock_inuse_init_net,
3486 	.exit = sock_inuse_exit_net,
3487 };
3488 
3489 static __init int net_inuse_init(void)
3490 {
3491 	if (register_pernet_subsys(&net_inuse_ops))
3492 		panic("Cannot initialize net inuse counters");
3493 
3494 	return 0;
3495 }
3496 
3497 core_initcall(net_inuse_init);
3498 
3499 static int assign_proto_idx(struct proto *prot)
3500 {
3501 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3502 
3503 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3504 		pr_err("PROTO_INUSE_NR exhausted\n");
3505 		return -ENOSPC;
3506 	}
3507 
3508 	set_bit(prot->inuse_idx, proto_inuse_idx);
3509 	return 0;
3510 }
3511 
3512 static void release_proto_idx(struct proto *prot)
3513 {
3514 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3515 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3516 }
3517 #else
3518 static inline int assign_proto_idx(struct proto *prot)
3519 {
3520 	return 0;
3521 }
3522 
3523 static inline void release_proto_idx(struct proto *prot)
3524 {
3525 }
3526 
3527 static void sock_inuse_add(struct net *net, int val)
3528 {
3529 }
3530 #endif
3531 
3532 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3533 {
3534 	if (!twsk_prot)
3535 		return;
3536 	kfree(twsk_prot->twsk_slab_name);
3537 	twsk_prot->twsk_slab_name = NULL;
3538 	kmem_cache_destroy(twsk_prot->twsk_slab);
3539 	twsk_prot->twsk_slab = NULL;
3540 }
3541 
3542 static int tw_prot_init(const struct proto *prot)
3543 {
3544 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3545 
3546 	if (!twsk_prot)
3547 		return 0;
3548 
3549 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3550 					      prot->name);
3551 	if (!twsk_prot->twsk_slab_name)
3552 		return -ENOMEM;
3553 
3554 	twsk_prot->twsk_slab =
3555 		kmem_cache_create(twsk_prot->twsk_slab_name,
3556 				  twsk_prot->twsk_obj_size, 0,
3557 				  SLAB_ACCOUNT | prot->slab_flags,
3558 				  NULL);
3559 	if (!twsk_prot->twsk_slab) {
3560 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3561 			prot->name);
3562 		return -ENOMEM;
3563 	}
3564 
3565 	return 0;
3566 }
3567 
3568 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3569 {
3570 	if (!rsk_prot)
3571 		return;
3572 	kfree(rsk_prot->slab_name);
3573 	rsk_prot->slab_name = NULL;
3574 	kmem_cache_destroy(rsk_prot->slab);
3575 	rsk_prot->slab = NULL;
3576 }
3577 
3578 static int req_prot_init(const struct proto *prot)
3579 {
3580 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3581 
3582 	if (!rsk_prot)
3583 		return 0;
3584 
3585 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3586 					prot->name);
3587 	if (!rsk_prot->slab_name)
3588 		return -ENOMEM;
3589 
3590 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3591 					   rsk_prot->obj_size, 0,
3592 					   SLAB_ACCOUNT | prot->slab_flags,
3593 					   NULL);
3594 
3595 	if (!rsk_prot->slab) {
3596 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3597 			prot->name);
3598 		return -ENOMEM;
3599 	}
3600 	return 0;
3601 }
3602 
3603 int proto_register(struct proto *prot, int alloc_slab)
3604 {
3605 	int ret = -ENOBUFS;
3606 
3607 	if (alloc_slab) {
3608 		prot->slab = kmem_cache_create_usercopy(prot->name,
3609 					prot->obj_size, 0,
3610 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3611 					prot->slab_flags,
3612 					prot->useroffset, prot->usersize,
3613 					NULL);
3614 
3615 		if (prot->slab == NULL) {
3616 			pr_crit("%s: Can't create sock SLAB cache!\n",
3617 				prot->name);
3618 			goto out;
3619 		}
3620 
3621 		if (req_prot_init(prot))
3622 			goto out_free_request_sock_slab;
3623 
3624 		if (tw_prot_init(prot))
3625 			goto out_free_timewait_sock_slab;
3626 	}
3627 
3628 	mutex_lock(&proto_list_mutex);
3629 	ret = assign_proto_idx(prot);
3630 	if (ret) {
3631 		mutex_unlock(&proto_list_mutex);
3632 		goto out_free_timewait_sock_slab;
3633 	}
3634 	list_add(&prot->node, &proto_list);
3635 	mutex_unlock(&proto_list_mutex);
3636 	return ret;
3637 
3638 out_free_timewait_sock_slab:
3639 	if (alloc_slab)
3640 		tw_prot_cleanup(prot->twsk_prot);
3641 out_free_request_sock_slab:
3642 	if (alloc_slab) {
3643 		req_prot_cleanup(prot->rsk_prot);
3644 
3645 		kmem_cache_destroy(prot->slab);
3646 		prot->slab = NULL;
3647 	}
3648 out:
3649 	return ret;
3650 }
3651 EXPORT_SYMBOL(proto_register);
3652 
3653 void proto_unregister(struct proto *prot)
3654 {
3655 	mutex_lock(&proto_list_mutex);
3656 	release_proto_idx(prot);
3657 	list_del(&prot->node);
3658 	mutex_unlock(&proto_list_mutex);
3659 
3660 	kmem_cache_destroy(prot->slab);
3661 	prot->slab = NULL;
3662 
3663 	req_prot_cleanup(prot->rsk_prot);
3664 	tw_prot_cleanup(prot->twsk_prot);
3665 }
3666 EXPORT_SYMBOL(proto_unregister);
3667 
3668 int sock_load_diag_module(int family, int protocol)
3669 {
3670 	if (!protocol) {
3671 		if (!sock_is_registered(family))
3672 			return -ENOENT;
3673 
3674 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3675 				      NETLINK_SOCK_DIAG, family);
3676 	}
3677 
3678 #ifdef CONFIG_INET
3679 	if (family == AF_INET &&
3680 	    protocol != IPPROTO_RAW &&
3681 	    protocol < MAX_INET_PROTOS &&
3682 	    !rcu_access_pointer(inet_protos[protocol]))
3683 		return -ENOENT;
3684 #endif
3685 
3686 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3687 			      NETLINK_SOCK_DIAG, family, protocol);
3688 }
3689 EXPORT_SYMBOL(sock_load_diag_module);
3690 
3691 #ifdef CONFIG_PROC_FS
3692 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3693 	__acquires(proto_list_mutex)
3694 {
3695 	mutex_lock(&proto_list_mutex);
3696 	return seq_list_start_head(&proto_list, *pos);
3697 }
3698 
3699 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3700 {
3701 	return seq_list_next(v, &proto_list, pos);
3702 }
3703 
3704 static void proto_seq_stop(struct seq_file *seq, void *v)
3705 	__releases(proto_list_mutex)
3706 {
3707 	mutex_unlock(&proto_list_mutex);
3708 }
3709 
3710 static char proto_method_implemented(const void *method)
3711 {
3712 	return method == NULL ? 'n' : 'y';
3713 }
3714 static long sock_prot_memory_allocated(struct proto *proto)
3715 {
3716 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3717 }
3718 
3719 static const char *sock_prot_memory_pressure(struct proto *proto)
3720 {
3721 	return proto->memory_pressure != NULL ?
3722 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3723 }
3724 
3725 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3726 {
3727 
3728 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
3729 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3730 		   proto->name,
3731 		   proto->obj_size,
3732 		   sock_prot_inuse_get(seq_file_net(seq), proto),
3733 		   sock_prot_memory_allocated(proto),
3734 		   sock_prot_memory_pressure(proto),
3735 		   proto->max_header,
3736 		   proto->slab == NULL ? "no" : "yes",
3737 		   module_name(proto->owner),
3738 		   proto_method_implemented(proto->close),
3739 		   proto_method_implemented(proto->connect),
3740 		   proto_method_implemented(proto->disconnect),
3741 		   proto_method_implemented(proto->accept),
3742 		   proto_method_implemented(proto->ioctl),
3743 		   proto_method_implemented(proto->init),
3744 		   proto_method_implemented(proto->destroy),
3745 		   proto_method_implemented(proto->shutdown),
3746 		   proto_method_implemented(proto->setsockopt),
3747 		   proto_method_implemented(proto->getsockopt),
3748 		   proto_method_implemented(proto->sendmsg),
3749 		   proto_method_implemented(proto->recvmsg),
3750 		   proto_method_implemented(proto->sendpage),
3751 		   proto_method_implemented(proto->bind),
3752 		   proto_method_implemented(proto->backlog_rcv),
3753 		   proto_method_implemented(proto->hash),
3754 		   proto_method_implemented(proto->unhash),
3755 		   proto_method_implemented(proto->get_port),
3756 		   proto_method_implemented(proto->enter_memory_pressure));
3757 }
3758 
3759 static int proto_seq_show(struct seq_file *seq, void *v)
3760 {
3761 	if (v == &proto_list)
3762 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3763 			   "protocol",
3764 			   "size",
3765 			   "sockets",
3766 			   "memory",
3767 			   "press",
3768 			   "maxhdr",
3769 			   "slab",
3770 			   "module",
3771 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3772 	else
3773 		proto_seq_printf(seq, list_entry(v, struct proto, node));
3774 	return 0;
3775 }
3776 
3777 static const struct seq_operations proto_seq_ops = {
3778 	.start  = proto_seq_start,
3779 	.next   = proto_seq_next,
3780 	.stop   = proto_seq_stop,
3781 	.show   = proto_seq_show,
3782 };
3783 
3784 static __net_init int proto_init_net(struct net *net)
3785 {
3786 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
3787 			sizeof(struct seq_net_private)))
3788 		return -ENOMEM;
3789 
3790 	return 0;
3791 }
3792 
3793 static __net_exit void proto_exit_net(struct net *net)
3794 {
3795 	remove_proc_entry("protocols", net->proc_net);
3796 }
3797 
3798 
3799 static __net_initdata struct pernet_operations proto_net_ops = {
3800 	.init = proto_init_net,
3801 	.exit = proto_exit_net,
3802 };
3803 
3804 static int __init proto_init(void)
3805 {
3806 	return register_pernet_subsys(&proto_net_ops);
3807 }
3808 
3809 subsys_initcall(proto_init);
3810 
3811 #endif /* PROC_FS */
3812 
3813 #ifdef CONFIG_NET_RX_BUSY_POLL
3814 bool sk_busy_loop_end(void *p, unsigned long start_time)
3815 {
3816 	struct sock *sk = p;
3817 
3818 	return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
3819 	       sk_busy_loop_timeout(sk, start_time);
3820 }
3821 EXPORT_SYMBOL(sk_busy_loop_end);
3822 #endif /* CONFIG_NET_RX_BUSY_POLL */
3823 
3824 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
3825 {
3826 	if (!sk->sk_prot->bind_add)
3827 		return -EOPNOTSUPP;
3828 	return sk->sk_prot->bind_add(sk, addr, addr_len);
3829 }
3830 EXPORT_SYMBOL(sock_bind_add);
3831