xref: /openbmc/linux/net/core/sock.c (revision b7b3c35e)
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 /**
148  * sk_ns_capable - General socket capability test
149  * @sk: Socket to use a capability on or through
150  * @user_ns: The user namespace of the capability to use
151  * @cap: The capability to use
152  *
153  * Test to see if the opener of the socket had when the socket was
154  * created and the current process has the capability @cap in the user
155  * namespace @user_ns.
156  */
157 bool sk_ns_capable(const struct sock *sk,
158 		   struct user_namespace *user_ns, int cap)
159 {
160 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
161 		ns_capable(user_ns, cap);
162 }
163 EXPORT_SYMBOL(sk_ns_capable);
164 
165 /**
166  * sk_capable - Socket global capability test
167  * @sk: Socket to use a capability on or through
168  * @cap: The global capability to use
169  *
170  * Test to see if the opener of the socket had when the socket was
171  * created and the current process has the capability @cap in all user
172  * namespaces.
173  */
174 bool sk_capable(const struct sock *sk, int cap)
175 {
176 	return sk_ns_capable(sk, &init_user_ns, cap);
177 }
178 EXPORT_SYMBOL(sk_capable);
179 
180 /**
181  * sk_net_capable - Network namespace socket capability test
182  * @sk: Socket to use a capability on or through
183  * @cap: The capability to use
184  *
185  * Test to see if the opener of the socket had when the socket was created
186  * and the current process has the capability @cap over the network namespace
187  * the socket is a member of.
188  */
189 bool sk_net_capable(const struct sock *sk, int cap)
190 {
191 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
192 }
193 EXPORT_SYMBOL(sk_net_capable);
194 
195 /*
196  * Each address family might have different locking rules, so we have
197  * one slock key per address family and separate keys for internal and
198  * userspace sockets.
199  */
200 static struct lock_class_key af_family_keys[AF_MAX];
201 static struct lock_class_key af_family_kern_keys[AF_MAX];
202 static struct lock_class_key af_family_slock_keys[AF_MAX];
203 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
204 
205 /*
206  * Make lock validator output more readable. (we pre-construct these
207  * strings build-time, so that runtime initialization of socket
208  * locks is fast):
209  */
210 
211 #define _sock_locks(x)						  \
212   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
213   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
214   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
215   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
216   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
217   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
218   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
219   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
220   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
221   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
222   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
223   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
224   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
225   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
226   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
227   x "AF_MCTP"  , \
228   x "AF_MAX"
229 
230 static const char *const af_family_key_strings[AF_MAX+1] = {
231 	_sock_locks("sk_lock-")
232 };
233 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
234 	_sock_locks("slock-")
235 };
236 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
237 	_sock_locks("clock-")
238 };
239 
240 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
241 	_sock_locks("k-sk_lock-")
242 };
243 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
244 	_sock_locks("k-slock-")
245 };
246 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
247 	_sock_locks("k-clock-")
248 };
249 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
250 	_sock_locks("rlock-")
251 };
252 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
253 	_sock_locks("wlock-")
254 };
255 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
256 	_sock_locks("elock-")
257 };
258 
259 /*
260  * sk_callback_lock and sk queues locking rules are per-address-family,
261  * so split the lock classes by using a per-AF key:
262  */
263 static struct lock_class_key af_callback_keys[AF_MAX];
264 static struct lock_class_key af_rlock_keys[AF_MAX];
265 static struct lock_class_key af_wlock_keys[AF_MAX];
266 static struct lock_class_key af_elock_keys[AF_MAX];
267 static struct lock_class_key af_kern_callback_keys[AF_MAX];
268 
269 /* Run time adjustable parameters. */
270 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
271 EXPORT_SYMBOL(sysctl_wmem_max);
272 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
273 EXPORT_SYMBOL(sysctl_rmem_max);
274 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
275 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
276 
277 /* Maximal space eaten by iovec or ancillary data plus some space */
278 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
279 EXPORT_SYMBOL(sysctl_optmem_max);
280 
281 int sysctl_tstamp_allow_data __read_mostly = 1;
282 
283 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
284 EXPORT_SYMBOL_GPL(memalloc_socks_key);
285 
286 /**
287  * sk_set_memalloc - sets %SOCK_MEMALLOC
288  * @sk: socket to set it on
289  *
290  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
291  * It's the responsibility of the admin to adjust min_free_kbytes
292  * to meet the requirements
293  */
294 void sk_set_memalloc(struct sock *sk)
295 {
296 	sock_set_flag(sk, SOCK_MEMALLOC);
297 	sk->sk_allocation |= __GFP_MEMALLOC;
298 	static_branch_inc(&memalloc_socks_key);
299 }
300 EXPORT_SYMBOL_GPL(sk_set_memalloc);
301 
302 void sk_clear_memalloc(struct sock *sk)
303 {
304 	sock_reset_flag(sk, SOCK_MEMALLOC);
305 	sk->sk_allocation &= ~__GFP_MEMALLOC;
306 	static_branch_dec(&memalloc_socks_key);
307 
308 	/*
309 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
310 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
311 	 * it has rmem allocations due to the last swapfile being deactivated
312 	 * but there is a risk that the socket is unusable due to exceeding
313 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
314 	 */
315 	sk_mem_reclaim(sk);
316 }
317 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
318 
319 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
320 {
321 	int ret;
322 	unsigned int noreclaim_flag;
323 
324 	/* these should have been dropped before queueing */
325 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
326 
327 	noreclaim_flag = memalloc_noreclaim_save();
328 	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
329 				 tcp_v6_do_rcv,
330 				 tcp_v4_do_rcv,
331 				 sk, skb);
332 	memalloc_noreclaim_restore(noreclaim_flag);
333 
334 	return ret;
335 }
336 EXPORT_SYMBOL(__sk_backlog_rcv);
337 
338 void sk_error_report(struct sock *sk)
339 {
340 	sk->sk_error_report(sk);
341 
342 	switch (sk->sk_family) {
343 	case AF_INET:
344 		fallthrough;
345 	case AF_INET6:
346 		trace_inet_sk_error_report(sk);
347 		break;
348 	default:
349 		break;
350 	}
351 }
352 EXPORT_SYMBOL(sk_error_report);
353 
354 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
355 {
356 	struct __kernel_sock_timeval tv;
357 
358 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
359 		tv.tv_sec = 0;
360 		tv.tv_usec = 0;
361 	} else {
362 		tv.tv_sec = timeo / HZ;
363 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
364 	}
365 
366 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
367 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
368 		*(struct old_timeval32 *)optval = tv32;
369 		return sizeof(tv32);
370 	}
371 
372 	if (old_timeval) {
373 		struct __kernel_old_timeval old_tv;
374 		old_tv.tv_sec = tv.tv_sec;
375 		old_tv.tv_usec = tv.tv_usec;
376 		*(struct __kernel_old_timeval *)optval = old_tv;
377 		return sizeof(old_tv);
378 	}
379 
380 	*(struct __kernel_sock_timeval *)optval = tv;
381 	return sizeof(tv);
382 }
383 EXPORT_SYMBOL(sock_get_timeout);
384 
385 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
386 			   sockptr_t optval, int optlen, bool old_timeval)
387 {
388 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
389 		struct old_timeval32 tv32;
390 
391 		if (optlen < sizeof(tv32))
392 			return -EINVAL;
393 
394 		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
395 			return -EFAULT;
396 		tv->tv_sec = tv32.tv_sec;
397 		tv->tv_usec = tv32.tv_usec;
398 	} else if (old_timeval) {
399 		struct __kernel_old_timeval old_tv;
400 
401 		if (optlen < sizeof(old_tv))
402 			return -EINVAL;
403 		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
404 			return -EFAULT;
405 		tv->tv_sec = old_tv.tv_sec;
406 		tv->tv_usec = old_tv.tv_usec;
407 	} else {
408 		if (optlen < sizeof(*tv))
409 			return -EINVAL;
410 		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
411 			return -EFAULT;
412 	}
413 
414 	return 0;
415 }
416 EXPORT_SYMBOL(sock_copy_user_timeval);
417 
418 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
419 			    bool old_timeval)
420 {
421 	struct __kernel_sock_timeval tv;
422 	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
423 
424 	if (err)
425 		return err;
426 
427 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
428 		return -EDOM;
429 
430 	if (tv.tv_sec < 0) {
431 		static int warned __read_mostly;
432 
433 		*timeo_p = 0;
434 		if (warned < 10 && net_ratelimit()) {
435 			warned++;
436 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
437 				__func__, current->comm, task_pid_nr(current));
438 		}
439 		return 0;
440 	}
441 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
442 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
443 		return 0;
444 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
445 		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
446 	return 0;
447 }
448 
449 static bool sock_needs_netstamp(const struct sock *sk)
450 {
451 	switch (sk->sk_family) {
452 	case AF_UNSPEC:
453 	case AF_UNIX:
454 		return false;
455 	default:
456 		return true;
457 	}
458 }
459 
460 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
461 {
462 	if (sk->sk_flags & flags) {
463 		sk->sk_flags &= ~flags;
464 		if (sock_needs_netstamp(sk) &&
465 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
466 			net_disable_timestamp();
467 	}
468 }
469 
470 
471 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
472 {
473 	unsigned long flags;
474 	struct sk_buff_head *list = &sk->sk_receive_queue;
475 
476 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
477 		atomic_inc(&sk->sk_drops);
478 		trace_sock_rcvqueue_full(sk, skb);
479 		return -ENOMEM;
480 	}
481 
482 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
483 		atomic_inc(&sk->sk_drops);
484 		return -ENOBUFS;
485 	}
486 
487 	skb->dev = NULL;
488 	skb_set_owner_r(skb, sk);
489 
490 	/* we escape from rcu protected region, make sure we dont leak
491 	 * a norefcounted dst
492 	 */
493 	skb_dst_force(skb);
494 
495 	spin_lock_irqsave(&list->lock, flags);
496 	sock_skb_set_dropcount(sk, skb);
497 	__skb_queue_tail(list, skb);
498 	spin_unlock_irqrestore(&list->lock, flags);
499 
500 	if (!sock_flag(sk, SOCK_DEAD))
501 		sk->sk_data_ready(sk);
502 	return 0;
503 }
504 EXPORT_SYMBOL(__sock_queue_rcv_skb);
505 
506 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
507 {
508 	int err;
509 
510 	err = sk_filter(sk, skb);
511 	if (err)
512 		return err;
513 
514 	return __sock_queue_rcv_skb(sk, skb);
515 }
516 EXPORT_SYMBOL(sock_queue_rcv_skb);
517 
518 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
519 		     const int nested, unsigned int trim_cap, bool refcounted)
520 {
521 	int rc = NET_RX_SUCCESS;
522 
523 	if (sk_filter_trim_cap(sk, skb, trim_cap))
524 		goto discard_and_relse;
525 
526 	skb->dev = NULL;
527 
528 	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
529 		atomic_inc(&sk->sk_drops);
530 		goto discard_and_relse;
531 	}
532 	if (nested)
533 		bh_lock_sock_nested(sk);
534 	else
535 		bh_lock_sock(sk);
536 	if (!sock_owned_by_user(sk)) {
537 		/*
538 		 * trylock + unlock semantics:
539 		 */
540 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
541 
542 		rc = sk_backlog_rcv(sk, skb);
543 
544 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
545 	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
546 		bh_unlock_sock(sk);
547 		atomic_inc(&sk->sk_drops);
548 		goto discard_and_relse;
549 	}
550 
551 	bh_unlock_sock(sk);
552 out:
553 	if (refcounted)
554 		sock_put(sk);
555 	return rc;
556 discard_and_relse:
557 	kfree_skb(skb);
558 	goto out;
559 }
560 EXPORT_SYMBOL(__sk_receive_skb);
561 
562 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
563 							  u32));
564 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
565 							   u32));
566 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
567 {
568 	struct dst_entry *dst = __sk_dst_get(sk);
569 
570 	if (dst && dst->obsolete &&
571 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
572 			       dst, cookie) == NULL) {
573 		sk_tx_queue_clear(sk);
574 		sk->sk_dst_pending_confirm = 0;
575 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
576 		dst_release(dst);
577 		return NULL;
578 	}
579 
580 	return dst;
581 }
582 EXPORT_SYMBOL(__sk_dst_check);
583 
584 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
585 {
586 	struct dst_entry *dst = sk_dst_get(sk);
587 
588 	if (dst && dst->obsolete &&
589 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
590 			       dst, cookie) == NULL) {
591 		sk_dst_reset(sk);
592 		dst_release(dst);
593 		return NULL;
594 	}
595 
596 	return dst;
597 }
598 EXPORT_SYMBOL(sk_dst_check);
599 
600 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
601 {
602 	int ret = -ENOPROTOOPT;
603 #ifdef CONFIG_NETDEVICES
604 	struct net *net = sock_net(sk);
605 
606 	/* Sorry... */
607 	ret = -EPERM;
608 	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
609 		goto out;
610 
611 	ret = -EINVAL;
612 	if (ifindex < 0)
613 		goto out;
614 
615 	sk->sk_bound_dev_if = ifindex;
616 	if (sk->sk_prot->rehash)
617 		sk->sk_prot->rehash(sk);
618 	sk_dst_reset(sk);
619 
620 	ret = 0;
621 
622 out:
623 #endif
624 
625 	return ret;
626 }
627 
628 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
629 {
630 	int ret;
631 
632 	if (lock_sk)
633 		lock_sock(sk);
634 	ret = sock_bindtoindex_locked(sk, ifindex);
635 	if (lock_sk)
636 		release_sock(sk);
637 
638 	return ret;
639 }
640 EXPORT_SYMBOL(sock_bindtoindex);
641 
642 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
643 {
644 	int ret = -ENOPROTOOPT;
645 #ifdef CONFIG_NETDEVICES
646 	struct net *net = sock_net(sk);
647 	char devname[IFNAMSIZ];
648 	int index;
649 
650 	ret = -EINVAL;
651 	if (optlen < 0)
652 		goto out;
653 
654 	/* Bind this socket to a particular device like "eth0",
655 	 * as specified in the passed interface name. If the
656 	 * name is "" or the option length is zero the socket
657 	 * is not bound.
658 	 */
659 	if (optlen > IFNAMSIZ - 1)
660 		optlen = IFNAMSIZ - 1;
661 	memset(devname, 0, sizeof(devname));
662 
663 	ret = -EFAULT;
664 	if (copy_from_sockptr(devname, optval, optlen))
665 		goto out;
666 
667 	index = 0;
668 	if (devname[0] != '\0') {
669 		struct net_device *dev;
670 
671 		rcu_read_lock();
672 		dev = dev_get_by_name_rcu(net, devname);
673 		if (dev)
674 			index = dev->ifindex;
675 		rcu_read_unlock();
676 		ret = -ENODEV;
677 		if (!dev)
678 			goto out;
679 	}
680 
681 	return sock_bindtoindex(sk, index, true);
682 out:
683 #endif
684 
685 	return ret;
686 }
687 
688 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
689 				int __user *optlen, int len)
690 {
691 	int ret = -ENOPROTOOPT;
692 #ifdef CONFIG_NETDEVICES
693 	struct net *net = sock_net(sk);
694 	char devname[IFNAMSIZ];
695 
696 	if (sk->sk_bound_dev_if == 0) {
697 		len = 0;
698 		goto zero;
699 	}
700 
701 	ret = -EINVAL;
702 	if (len < IFNAMSIZ)
703 		goto out;
704 
705 	ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
706 	if (ret)
707 		goto out;
708 
709 	len = strlen(devname) + 1;
710 
711 	ret = -EFAULT;
712 	if (copy_to_user(optval, devname, len))
713 		goto out;
714 
715 zero:
716 	ret = -EFAULT;
717 	if (put_user(len, optlen))
718 		goto out;
719 
720 	ret = 0;
721 
722 out:
723 #endif
724 
725 	return ret;
726 }
727 
728 bool sk_mc_loop(struct sock *sk)
729 {
730 	if (dev_recursion_level())
731 		return false;
732 	if (!sk)
733 		return true;
734 	switch (sk->sk_family) {
735 	case AF_INET:
736 		return inet_sk(sk)->mc_loop;
737 #if IS_ENABLED(CONFIG_IPV6)
738 	case AF_INET6:
739 		return inet6_sk(sk)->mc_loop;
740 #endif
741 	}
742 	WARN_ON_ONCE(1);
743 	return true;
744 }
745 EXPORT_SYMBOL(sk_mc_loop);
746 
747 void sock_set_reuseaddr(struct sock *sk)
748 {
749 	lock_sock(sk);
750 	sk->sk_reuse = SK_CAN_REUSE;
751 	release_sock(sk);
752 }
753 EXPORT_SYMBOL(sock_set_reuseaddr);
754 
755 void sock_set_reuseport(struct sock *sk)
756 {
757 	lock_sock(sk);
758 	sk->sk_reuseport = true;
759 	release_sock(sk);
760 }
761 EXPORT_SYMBOL(sock_set_reuseport);
762 
763 void sock_no_linger(struct sock *sk)
764 {
765 	lock_sock(sk);
766 	sk->sk_lingertime = 0;
767 	sock_set_flag(sk, SOCK_LINGER);
768 	release_sock(sk);
769 }
770 EXPORT_SYMBOL(sock_no_linger);
771 
772 void sock_set_priority(struct sock *sk, u32 priority)
773 {
774 	lock_sock(sk);
775 	sk->sk_priority = priority;
776 	release_sock(sk);
777 }
778 EXPORT_SYMBOL(sock_set_priority);
779 
780 void sock_set_sndtimeo(struct sock *sk, s64 secs)
781 {
782 	lock_sock(sk);
783 	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
784 		sk->sk_sndtimeo = secs * HZ;
785 	else
786 		sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
787 	release_sock(sk);
788 }
789 EXPORT_SYMBOL(sock_set_sndtimeo);
790 
791 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
792 {
793 	if (val)  {
794 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
795 		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
796 		sock_set_flag(sk, SOCK_RCVTSTAMP);
797 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
798 	} else {
799 		sock_reset_flag(sk, SOCK_RCVTSTAMP);
800 		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
801 	}
802 }
803 
804 void sock_enable_timestamps(struct sock *sk)
805 {
806 	lock_sock(sk);
807 	__sock_set_timestamps(sk, true, false, true);
808 	release_sock(sk);
809 }
810 EXPORT_SYMBOL(sock_enable_timestamps);
811 
812 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
813 {
814 	switch (optname) {
815 	case SO_TIMESTAMP_OLD:
816 		__sock_set_timestamps(sk, valbool, false, false);
817 		break;
818 	case SO_TIMESTAMP_NEW:
819 		__sock_set_timestamps(sk, valbool, true, false);
820 		break;
821 	case SO_TIMESTAMPNS_OLD:
822 		__sock_set_timestamps(sk, valbool, false, true);
823 		break;
824 	case SO_TIMESTAMPNS_NEW:
825 		__sock_set_timestamps(sk, valbool, true, true);
826 		break;
827 	}
828 }
829 
830 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
831 {
832 	struct net *net = sock_net(sk);
833 	struct net_device *dev = NULL;
834 	bool match = false;
835 	int *vclock_index;
836 	int i, num;
837 
838 	if (sk->sk_bound_dev_if)
839 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
840 
841 	if (!dev) {
842 		pr_err("%s: sock not bind to device\n", __func__);
843 		return -EOPNOTSUPP;
844 	}
845 
846 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
847 	dev_put(dev);
848 
849 	for (i = 0; i < num; i++) {
850 		if (*(vclock_index + i) == phc_index) {
851 			match = true;
852 			break;
853 		}
854 	}
855 
856 	if (num > 0)
857 		kfree(vclock_index);
858 
859 	if (!match)
860 		return -EINVAL;
861 
862 	sk->sk_bind_phc = phc_index;
863 
864 	return 0;
865 }
866 
867 int sock_set_timestamping(struct sock *sk, int optname,
868 			  struct so_timestamping timestamping)
869 {
870 	int val = timestamping.flags;
871 	int ret;
872 
873 	if (val & ~SOF_TIMESTAMPING_MASK)
874 		return -EINVAL;
875 
876 	if (val & SOF_TIMESTAMPING_OPT_ID &&
877 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
878 		if (sk_is_tcp(sk)) {
879 			if ((1 << sk->sk_state) &
880 			    (TCPF_CLOSE | TCPF_LISTEN))
881 				return -EINVAL;
882 			sk->sk_tskey = tcp_sk(sk)->snd_una;
883 		} else {
884 			sk->sk_tskey = 0;
885 		}
886 	}
887 
888 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
889 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
890 		return -EINVAL;
891 
892 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
893 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
894 		if (ret)
895 			return ret;
896 	}
897 
898 	sk->sk_tsflags = val;
899 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
900 
901 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
902 		sock_enable_timestamp(sk,
903 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
904 	else
905 		sock_disable_timestamp(sk,
906 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
907 	return 0;
908 }
909 
910 void sock_set_keepalive(struct sock *sk)
911 {
912 	lock_sock(sk);
913 	if (sk->sk_prot->keepalive)
914 		sk->sk_prot->keepalive(sk, true);
915 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
916 	release_sock(sk);
917 }
918 EXPORT_SYMBOL(sock_set_keepalive);
919 
920 static void __sock_set_rcvbuf(struct sock *sk, int val)
921 {
922 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
923 	 * as a negative value.
924 	 */
925 	val = min_t(int, val, INT_MAX / 2);
926 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
927 
928 	/* We double it on the way in to account for "struct sk_buff" etc.
929 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
930 	 * will allow that much actual data to be received on that socket.
931 	 *
932 	 * Applications are unaware that "struct sk_buff" and other overheads
933 	 * allocate from the receive buffer during socket buffer allocation.
934 	 *
935 	 * And after considering the possible alternatives, returning the value
936 	 * we actually used in getsockopt is the most desirable behavior.
937 	 */
938 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
939 }
940 
941 void sock_set_rcvbuf(struct sock *sk, int val)
942 {
943 	lock_sock(sk);
944 	__sock_set_rcvbuf(sk, val);
945 	release_sock(sk);
946 }
947 EXPORT_SYMBOL(sock_set_rcvbuf);
948 
949 static void __sock_set_mark(struct sock *sk, u32 val)
950 {
951 	if (val != sk->sk_mark) {
952 		sk->sk_mark = val;
953 		sk_dst_reset(sk);
954 	}
955 }
956 
957 void sock_set_mark(struct sock *sk, u32 val)
958 {
959 	lock_sock(sk);
960 	__sock_set_mark(sk, val);
961 	release_sock(sk);
962 }
963 EXPORT_SYMBOL(sock_set_mark);
964 
965 static void sock_release_reserved_memory(struct sock *sk, int bytes)
966 {
967 	/* Round down bytes to multiple of pages */
968 	bytes &= ~(SK_MEM_QUANTUM - 1);
969 
970 	WARN_ON(bytes > sk->sk_reserved_mem);
971 	sk->sk_reserved_mem -= bytes;
972 	sk_mem_reclaim(sk);
973 }
974 
975 static int sock_reserve_memory(struct sock *sk, int bytes)
976 {
977 	long allocated;
978 	bool charged;
979 	int pages;
980 
981 	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
982 		return -EOPNOTSUPP;
983 
984 	if (!bytes)
985 		return 0;
986 
987 	pages = sk_mem_pages(bytes);
988 
989 	/* pre-charge to memcg */
990 	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
991 					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
992 	if (!charged)
993 		return -ENOMEM;
994 
995 	/* pre-charge to forward_alloc */
996 	allocated = sk_memory_allocated_add(sk, pages);
997 	/* If the system goes into memory pressure with this
998 	 * precharge, give up and return error.
999 	 */
1000 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1001 		sk_memory_allocated_sub(sk, pages);
1002 		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1003 		return -ENOMEM;
1004 	}
1005 	sk->sk_forward_alloc += pages << SK_MEM_QUANTUM_SHIFT;
1006 
1007 	sk->sk_reserved_mem += pages << SK_MEM_QUANTUM_SHIFT;
1008 
1009 	return 0;
1010 }
1011 
1012 /*
1013  *	This is meant for all protocols to use and covers goings on
1014  *	at the socket level. Everything here is generic.
1015  */
1016 
1017 int sock_setsockopt(struct socket *sock, int level, int optname,
1018 		    sockptr_t optval, unsigned int optlen)
1019 {
1020 	struct so_timestamping timestamping;
1021 	struct sock_txtime sk_txtime;
1022 	struct sock *sk = sock->sk;
1023 	int val;
1024 	int valbool;
1025 	struct linger ling;
1026 	int ret = 0;
1027 
1028 	/*
1029 	 *	Options without arguments
1030 	 */
1031 
1032 	if (optname == SO_BINDTODEVICE)
1033 		return sock_setbindtodevice(sk, optval, optlen);
1034 
1035 	if (optlen < sizeof(int))
1036 		return -EINVAL;
1037 
1038 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1039 		return -EFAULT;
1040 
1041 	valbool = val ? 1 : 0;
1042 
1043 	lock_sock(sk);
1044 
1045 	switch (optname) {
1046 	case SO_DEBUG:
1047 		if (val && !capable(CAP_NET_ADMIN))
1048 			ret = -EACCES;
1049 		else
1050 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1051 		break;
1052 	case SO_REUSEADDR:
1053 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1054 		break;
1055 	case SO_REUSEPORT:
1056 		sk->sk_reuseport = valbool;
1057 		break;
1058 	case SO_TYPE:
1059 	case SO_PROTOCOL:
1060 	case SO_DOMAIN:
1061 	case SO_ERROR:
1062 		ret = -ENOPROTOOPT;
1063 		break;
1064 	case SO_DONTROUTE:
1065 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1066 		sk_dst_reset(sk);
1067 		break;
1068 	case SO_BROADCAST:
1069 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1070 		break;
1071 	case SO_SNDBUF:
1072 		/* Don't error on this BSD doesn't and if you think
1073 		 * about it this is right. Otherwise apps have to
1074 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1075 		 * are treated in BSD as hints
1076 		 */
1077 		val = min_t(u32, val, sysctl_wmem_max);
1078 set_sndbuf:
1079 		/* Ensure val * 2 fits into an int, to prevent max_t()
1080 		 * from treating it as a negative value.
1081 		 */
1082 		val = min_t(int, val, INT_MAX / 2);
1083 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1084 		WRITE_ONCE(sk->sk_sndbuf,
1085 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1086 		/* Wake up sending tasks if we upped the value. */
1087 		sk->sk_write_space(sk);
1088 		break;
1089 
1090 	case SO_SNDBUFFORCE:
1091 		if (!capable(CAP_NET_ADMIN)) {
1092 			ret = -EPERM;
1093 			break;
1094 		}
1095 
1096 		/* No negative values (to prevent underflow, as val will be
1097 		 * multiplied by 2).
1098 		 */
1099 		if (val < 0)
1100 			val = 0;
1101 		goto set_sndbuf;
1102 
1103 	case SO_RCVBUF:
1104 		/* Don't error on this BSD doesn't and if you think
1105 		 * about it this is right. Otherwise apps have to
1106 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1107 		 * are treated in BSD as hints
1108 		 */
1109 		__sock_set_rcvbuf(sk, min_t(u32, val, sysctl_rmem_max));
1110 		break;
1111 
1112 	case SO_RCVBUFFORCE:
1113 		if (!capable(CAP_NET_ADMIN)) {
1114 			ret = -EPERM;
1115 			break;
1116 		}
1117 
1118 		/* No negative values (to prevent underflow, as val will be
1119 		 * multiplied by 2).
1120 		 */
1121 		__sock_set_rcvbuf(sk, max(val, 0));
1122 		break;
1123 
1124 	case SO_KEEPALIVE:
1125 		if (sk->sk_prot->keepalive)
1126 			sk->sk_prot->keepalive(sk, valbool);
1127 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1128 		break;
1129 
1130 	case SO_OOBINLINE:
1131 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1132 		break;
1133 
1134 	case SO_NO_CHECK:
1135 		sk->sk_no_check_tx = valbool;
1136 		break;
1137 
1138 	case SO_PRIORITY:
1139 		if ((val >= 0 && val <= 6) ||
1140 		    ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1141 		    ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1142 			sk->sk_priority = val;
1143 		else
1144 			ret = -EPERM;
1145 		break;
1146 
1147 	case SO_LINGER:
1148 		if (optlen < sizeof(ling)) {
1149 			ret = -EINVAL;	/* 1003.1g */
1150 			break;
1151 		}
1152 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1153 			ret = -EFAULT;
1154 			break;
1155 		}
1156 		if (!ling.l_onoff)
1157 			sock_reset_flag(sk, SOCK_LINGER);
1158 		else {
1159 #if (BITS_PER_LONG == 32)
1160 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
1161 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
1162 			else
1163 #endif
1164 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
1165 			sock_set_flag(sk, SOCK_LINGER);
1166 		}
1167 		break;
1168 
1169 	case SO_BSDCOMPAT:
1170 		break;
1171 
1172 	case SO_PASSCRED:
1173 		if (valbool)
1174 			set_bit(SOCK_PASSCRED, &sock->flags);
1175 		else
1176 			clear_bit(SOCK_PASSCRED, &sock->flags);
1177 		break;
1178 
1179 	case SO_TIMESTAMP_OLD:
1180 	case SO_TIMESTAMP_NEW:
1181 	case SO_TIMESTAMPNS_OLD:
1182 	case SO_TIMESTAMPNS_NEW:
1183 		sock_set_timestamp(sk, optname, valbool);
1184 		break;
1185 
1186 	case SO_TIMESTAMPING_NEW:
1187 	case SO_TIMESTAMPING_OLD:
1188 		if (optlen == sizeof(timestamping)) {
1189 			if (copy_from_sockptr(&timestamping, optval,
1190 					      sizeof(timestamping))) {
1191 				ret = -EFAULT;
1192 				break;
1193 			}
1194 		} else {
1195 			memset(&timestamping, 0, sizeof(timestamping));
1196 			timestamping.flags = val;
1197 		}
1198 		ret = sock_set_timestamping(sk, optname, timestamping);
1199 		break;
1200 
1201 	case SO_RCVLOWAT:
1202 		if (val < 0)
1203 			val = INT_MAX;
1204 		if (sock->ops->set_rcvlowat)
1205 			ret = sock->ops->set_rcvlowat(sk, val);
1206 		else
1207 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1208 		break;
1209 
1210 	case SO_RCVTIMEO_OLD:
1211 	case SO_RCVTIMEO_NEW:
1212 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1213 				       optlen, optname == SO_RCVTIMEO_OLD);
1214 		break;
1215 
1216 	case SO_SNDTIMEO_OLD:
1217 	case SO_SNDTIMEO_NEW:
1218 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1219 				       optlen, optname == SO_SNDTIMEO_OLD);
1220 		break;
1221 
1222 	case SO_ATTACH_FILTER: {
1223 		struct sock_fprog fprog;
1224 
1225 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1226 		if (!ret)
1227 			ret = sk_attach_filter(&fprog, sk);
1228 		break;
1229 	}
1230 	case SO_ATTACH_BPF:
1231 		ret = -EINVAL;
1232 		if (optlen == sizeof(u32)) {
1233 			u32 ufd;
1234 
1235 			ret = -EFAULT;
1236 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1237 				break;
1238 
1239 			ret = sk_attach_bpf(ufd, sk);
1240 		}
1241 		break;
1242 
1243 	case SO_ATTACH_REUSEPORT_CBPF: {
1244 		struct sock_fprog fprog;
1245 
1246 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1247 		if (!ret)
1248 			ret = sk_reuseport_attach_filter(&fprog, sk);
1249 		break;
1250 	}
1251 	case SO_ATTACH_REUSEPORT_EBPF:
1252 		ret = -EINVAL;
1253 		if (optlen == sizeof(u32)) {
1254 			u32 ufd;
1255 
1256 			ret = -EFAULT;
1257 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1258 				break;
1259 
1260 			ret = sk_reuseport_attach_bpf(ufd, sk);
1261 		}
1262 		break;
1263 
1264 	case SO_DETACH_REUSEPORT_BPF:
1265 		ret = reuseport_detach_prog(sk);
1266 		break;
1267 
1268 	case SO_DETACH_FILTER:
1269 		ret = sk_detach_filter(sk);
1270 		break;
1271 
1272 	case SO_LOCK_FILTER:
1273 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1274 			ret = -EPERM;
1275 		else
1276 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1277 		break;
1278 
1279 	case SO_PASSSEC:
1280 		if (valbool)
1281 			set_bit(SOCK_PASSSEC, &sock->flags);
1282 		else
1283 			clear_bit(SOCK_PASSSEC, &sock->flags);
1284 		break;
1285 	case SO_MARK:
1286 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1287 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1288 			ret = -EPERM;
1289 			break;
1290 		}
1291 
1292 		__sock_set_mark(sk, val);
1293 		break;
1294 
1295 	case SO_RXQ_OVFL:
1296 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1297 		break;
1298 
1299 	case SO_WIFI_STATUS:
1300 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1301 		break;
1302 
1303 	case SO_PEEK_OFF:
1304 		if (sock->ops->set_peek_off)
1305 			ret = sock->ops->set_peek_off(sk, val);
1306 		else
1307 			ret = -EOPNOTSUPP;
1308 		break;
1309 
1310 	case SO_NOFCS:
1311 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1312 		break;
1313 
1314 	case SO_SELECT_ERR_QUEUE:
1315 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1316 		break;
1317 
1318 #ifdef CONFIG_NET_RX_BUSY_POLL
1319 	case SO_BUSY_POLL:
1320 		/* allow unprivileged users to decrease the value */
1321 		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1322 			ret = -EPERM;
1323 		else {
1324 			if (val < 0)
1325 				ret = -EINVAL;
1326 			else
1327 				WRITE_ONCE(sk->sk_ll_usec, val);
1328 		}
1329 		break;
1330 	case SO_PREFER_BUSY_POLL:
1331 		if (valbool && !capable(CAP_NET_ADMIN))
1332 			ret = -EPERM;
1333 		else
1334 			WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1335 		break;
1336 	case SO_BUSY_POLL_BUDGET:
1337 		if (val > READ_ONCE(sk->sk_busy_poll_budget) && !capable(CAP_NET_ADMIN)) {
1338 			ret = -EPERM;
1339 		} else {
1340 			if (val < 0 || val > U16_MAX)
1341 				ret = -EINVAL;
1342 			else
1343 				WRITE_ONCE(sk->sk_busy_poll_budget, val);
1344 		}
1345 		break;
1346 #endif
1347 
1348 	case SO_MAX_PACING_RATE:
1349 		{
1350 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1351 
1352 		if (sizeof(ulval) != sizeof(val) &&
1353 		    optlen >= sizeof(ulval) &&
1354 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1355 			ret = -EFAULT;
1356 			break;
1357 		}
1358 		if (ulval != ~0UL)
1359 			cmpxchg(&sk->sk_pacing_status,
1360 				SK_PACING_NONE,
1361 				SK_PACING_NEEDED);
1362 		sk->sk_max_pacing_rate = ulval;
1363 		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1364 		break;
1365 		}
1366 	case SO_INCOMING_CPU:
1367 		WRITE_ONCE(sk->sk_incoming_cpu, val);
1368 		break;
1369 
1370 	case SO_CNX_ADVICE:
1371 		if (val == 1)
1372 			dst_negative_advice(sk);
1373 		break;
1374 
1375 	case SO_ZEROCOPY:
1376 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1377 			if (!(sk_is_tcp(sk) ||
1378 			      (sk->sk_type == SOCK_DGRAM &&
1379 			       sk->sk_protocol == IPPROTO_UDP)))
1380 				ret = -ENOTSUPP;
1381 		} else if (sk->sk_family != PF_RDS) {
1382 			ret = -ENOTSUPP;
1383 		}
1384 		if (!ret) {
1385 			if (val < 0 || val > 1)
1386 				ret = -EINVAL;
1387 			else
1388 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1389 		}
1390 		break;
1391 
1392 	case SO_TXTIME:
1393 		if (optlen != sizeof(struct sock_txtime)) {
1394 			ret = -EINVAL;
1395 			break;
1396 		} else if (copy_from_sockptr(&sk_txtime, optval,
1397 			   sizeof(struct sock_txtime))) {
1398 			ret = -EFAULT;
1399 			break;
1400 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1401 			ret = -EINVAL;
1402 			break;
1403 		}
1404 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1405 		 * scheduler has enough safe guards.
1406 		 */
1407 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1408 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1409 			ret = -EPERM;
1410 			break;
1411 		}
1412 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1413 		sk->sk_clockid = sk_txtime.clockid;
1414 		sk->sk_txtime_deadline_mode =
1415 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1416 		sk->sk_txtime_report_errors =
1417 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1418 		break;
1419 
1420 	case SO_BINDTOIFINDEX:
1421 		ret = sock_bindtoindex_locked(sk, val);
1422 		break;
1423 
1424 	case SO_BUF_LOCK:
1425 		if (val & ~SOCK_BUF_LOCK_MASK) {
1426 			ret = -EINVAL;
1427 			break;
1428 		}
1429 		sk->sk_userlocks = val | (sk->sk_userlocks &
1430 					  ~SOCK_BUF_LOCK_MASK);
1431 		break;
1432 
1433 	case SO_RESERVE_MEM:
1434 	{
1435 		int delta;
1436 
1437 		if (val < 0) {
1438 			ret = -EINVAL;
1439 			break;
1440 		}
1441 
1442 		delta = val - sk->sk_reserved_mem;
1443 		if (delta < 0)
1444 			sock_release_reserved_memory(sk, -delta);
1445 		else
1446 			ret = sock_reserve_memory(sk, delta);
1447 		break;
1448 	}
1449 
1450 	default:
1451 		ret = -ENOPROTOOPT;
1452 		break;
1453 	}
1454 	release_sock(sk);
1455 	return ret;
1456 }
1457 EXPORT_SYMBOL(sock_setsockopt);
1458 
1459 static const struct cred *sk_get_peer_cred(struct sock *sk)
1460 {
1461 	const struct cred *cred;
1462 
1463 	spin_lock(&sk->sk_peer_lock);
1464 	cred = get_cred(sk->sk_peer_cred);
1465 	spin_unlock(&sk->sk_peer_lock);
1466 
1467 	return cred;
1468 }
1469 
1470 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1471 			  struct ucred *ucred)
1472 {
1473 	ucred->pid = pid_vnr(pid);
1474 	ucred->uid = ucred->gid = -1;
1475 	if (cred) {
1476 		struct user_namespace *current_ns = current_user_ns();
1477 
1478 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1479 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1480 	}
1481 }
1482 
1483 static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1484 {
1485 	struct user_namespace *user_ns = current_user_ns();
1486 	int i;
1487 
1488 	for (i = 0; i < src->ngroups; i++)
1489 		if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1490 			return -EFAULT;
1491 
1492 	return 0;
1493 }
1494 
1495 int sock_getsockopt(struct socket *sock, int level, int optname,
1496 		    char __user *optval, int __user *optlen)
1497 {
1498 	struct sock *sk = sock->sk;
1499 
1500 	union {
1501 		int val;
1502 		u64 val64;
1503 		unsigned long ulval;
1504 		struct linger ling;
1505 		struct old_timeval32 tm32;
1506 		struct __kernel_old_timeval tm;
1507 		struct  __kernel_sock_timeval stm;
1508 		struct sock_txtime txtime;
1509 		struct so_timestamping timestamping;
1510 	} v;
1511 
1512 	int lv = sizeof(int);
1513 	int len;
1514 
1515 	if (get_user(len, optlen))
1516 		return -EFAULT;
1517 	if (len < 0)
1518 		return -EINVAL;
1519 
1520 	memset(&v, 0, sizeof(v));
1521 
1522 	switch (optname) {
1523 	case SO_DEBUG:
1524 		v.val = sock_flag(sk, SOCK_DBG);
1525 		break;
1526 
1527 	case SO_DONTROUTE:
1528 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1529 		break;
1530 
1531 	case SO_BROADCAST:
1532 		v.val = sock_flag(sk, SOCK_BROADCAST);
1533 		break;
1534 
1535 	case SO_SNDBUF:
1536 		v.val = sk->sk_sndbuf;
1537 		break;
1538 
1539 	case SO_RCVBUF:
1540 		v.val = sk->sk_rcvbuf;
1541 		break;
1542 
1543 	case SO_REUSEADDR:
1544 		v.val = sk->sk_reuse;
1545 		break;
1546 
1547 	case SO_REUSEPORT:
1548 		v.val = sk->sk_reuseport;
1549 		break;
1550 
1551 	case SO_KEEPALIVE:
1552 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1553 		break;
1554 
1555 	case SO_TYPE:
1556 		v.val = sk->sk_type;
1557 		break;
1558 
1559 	case SO_PROTOCOL:
1560 		v.val = sk->sk_protocol;
1561 		break;
1562 
1563 	case SO_DOMAIN:
1564 		v.val = sk->sk_family;
1565 		break;
1566 
1567 	case SO_ERROR:
1568 		v.val = -sock_error(sk);
1569 		if (v.val == 0)
1570 			v.val = xchg(&sk->sk_err_soft, 0);
1571 		break;
1572 
1573 	case SO_OOBINLINE:
1574 		v.val = sock_flag(sk, SOCK_URGINLINE);
1575 		break;
1576 
1577 	case SO_NO_CHECK:
1578 		v.val = sk->sk_no_check_tx;
1579 		break;
1580 
1581 	case SO_PRIORITY:
1582 		v.val = sk->sk_priority;
1583 		break;
1584 
1585 	case SO_LINGER:
1586 		lv		= sizeof(v.ling);
1587 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1588 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1589 		break;
1590 
1591 	case SO_BSDCOMPAT:
1592 		break;
1593 
1594 	case SO_TIMESTAMP_OLD:
1595 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1596 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1597 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1598 		break;
1599 
1600 	case SO_TIMESTAMPNS_OLD:
1601 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1602 		break;
1603 
1604 	case SO_TIMESTAMP_NEW:
1605 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1606 		break;
1607 
1608 	case SO_TIMESTAMPNS_NEW:
1609 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1610 		break;
1611 
1612 	case SO_TIMESTAMPING_OLD:
1613 		lv = sizeof(v.timestamping);
1614 		v.timestamping.flags = sk->sk_tsflags;
1615 		v.timestamping.bind_phc = sk->sk_bind_phc;
1616 		break;
1617 
1618 	case SO_RCVTIMEO_OLD:
1619 	case SO_RCVTIMEO_NEW:
1620 		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1621 		break;
1622 
1623 	case SO_SNDTIMEO_OLD:
1624 	case SO_SNDTIMEO_NEW:
1625 		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1626 		break;
1627 
1628 	case SO_RCVLOWAT:
1629 		v.val = sk->sk_rcvlowat;
1630 		break;
1631 
1632 	case SO_SNDLOWAT:
1633 		v.val = 1;
1634 		break;
1635 
1636 	case SO_PASSCRED:
1637 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1638 		break;
1639 
1640 	case SO_PEERCRED:
1641 	{
1642 		struct ucred peercred;
1643 		if (len > sizeof(peercred))
1644 			len = sizeof(peercred);
1645 
1646 		spin_lock(&sk->sk_peer_lock);
1647 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1648 		spin_unlock(&sk->sk_peer_lock);
1649 
1650 		if (copy_to_user(optval, &peercred, len))
1651 			return -EFAULT;
1652 		goto lenout;
1653 	}
1654 
1655 	case SO_PEERGROUPS:
1656 	{
1657 		const struct cred *cred;
1658 		int ret, n;
1659 
1660 		cred = sk_get_peer_cred(sk);
1661 		if (!cred)
1662 			return -ENODATA;
1663 
1664 		n = cred->group_info->ngroups;
1665 		if (len < n * sizeof(gid_t)) {
1666 			len = n * sizeof(gid_t);
1667 			put_cred(cred);
1668 			return put_user(len, optlen) ? -EFAULT : -ERANGE;
1669 		}
1670 		len = n * sizeof(gid_t);
1671 
1672 		ret = groups_to_user((gid_t __user *)optval, cred->group_info);
1673 		put_cred(cred);
1674 		if (ret)
1675 			return ret;
1676 		goto lenout;
1677 	}
1678 
1679 	case SO_PEERNAME:
1680 	{
1681 		char address[128];
1682 
1683 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1684 		if (lv < 0)
1685 			return -ENOTCONN;
1686 		if (lv < len)
1687 			return -EINVAL;
1688 		if (copy_to_user(optval, address, len))
1689 			return -EFAULT;
1690 		goto lenout;
1691 	}
1692 
1693 	/* Dubious BSD thing... Probably nobody even uses it, but
1694 	 * the UNIX standard wants it for whatever reason... -DaveM
1695 	 */
1696 	case SO_ACCEPTCONN:
1697 		v.val = sk->sk_state == TCP_LISTEN;
1698 		break;
1699 
1700 	case SO_PASSSEC:
1701 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1702 		break;
1703 
1704 	case SO_PEERSEC:
1705 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1706 
1707 	case SO_MARK:
1708 		v.val = sk->sk_mark;
1709 		break;
1710 
1711 	case SO_RXQ_OVFL:
1712 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1713 		break;
1714 
1715 	case SO_WIFI_STATUS:
1716 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1717 		break;
1718 
1719 	case SO_PEEK_OFF:
1720 		if (!sock->ops->set_peek_off)
1721 			return -EOPNOTSUPP;
1722 
1723 		v.val = sk->sk_peek_off;
1724 		break;
1725 	case SO_NOFCS:
1726 		v.val = sock_flag(sk, SOCK_NOFCS);
1727 		break;
1728 
1729 	case SO_BINDTODEVICE:
1730 		return sock_getbindtodevice(sk, optval, optlen, len);
1731 
1732 	case SO_GET_FILTER:
1733 		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1734 		if (len < 0)
1735 			return len;
1736 
1737 		goto lenout;
1738 
1739 	case SO_LOCK_FILTER:
1740 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1741 		break;
1742 
1743 	case SO_BPF_EXTENSIONS:
1744 		v.val = bpf_tell_extensions();
1745 		break;
1746 
1747 	case SO_SELECT_ERR_QUEUE:
1748 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1749 		break;
1750 
1751 #ifdef CONFIG_NET_RX_BUSY_POLL
1752 	case SO_BUSY_POLL:
1753 		v.val = sk->sk_ll_usec;
1754 		break;
1755 	case SO_PREFER_BUSY_POLL:
1756 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1757 		break;
1758 #endif
1759 
1760 	case SO_MAX_PACING_RATE:
1761 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1762 			lv = sizeof(v.ulval);
1763 			v.ulval = sk->sk_max_pacing_rate;
1764 		} else {
1765 			/* 32bit version */
1766 			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1767 		}
1768 		break;
1769 
1770 	case SO_INCOMING_CPU:
1771 		v.val = READ_ONCE(sk->sk_incoming_cpu);
1772 		break;
1773 
1774 	case SO_MEMINFO:
1775 	{
1776 		u32 meminfo[SK_MEMINFO_VARS];
1777 
1778 		sk_get_meminfo(sk, meminfo);
1779 
1780 		len = min_t(unsigned int, len, sizeof(meminfo));
1781 		if (copy_to_user(optval, &meminfo, len))
1782 			return -EFAULT;
1783 
1784 		goto lenout;
1785 	}
1786 
1787 #ifdef CONFIG_NET_RX_BUSY_POLL
1788 	case SO_INCOMING_NAPI_ID:
1789 		v.val = READ_ONCE(sk->sk_napi_id);
1790 
1791 		/* aggregate non-NAPI IDs down to 0 */
1792 		if (v.val < MIN_NAPI_ID)
1793 			v.val = 0;
1794 
1795 		break;
1796 #endif
1797 
1798 	case SO_COOKIE:
1799 		lv = sizeof(u64);
1800 		if (len < lv)
1801 			return -EINVAL;
1802 		v.val64 = sock_gen_cookie(sk);
1803 		break;
1804 
1805 	case SO_ZEROCOPY:
1806 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1807 		break;
1808 
1809 	case SO_TXTIME:
1810 		lv = sizeof(v.txtime);
1811 		v.txtime.clockid = sk->sk_clockid;
1812 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1813 				  SOF_TXTIME_DEADLINE_MODE : 0;
1814 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1815 				  SOF_TXTIME_REPORT_ERRORS : 0;
1816 		break;
1817 
1818 	case SO_BINDTOIFINDEX:
1819 		v.val = sk->sk_bound_dev_if;
1820 		break;
1821 
1822 	case SO_NETNS_COOKIE:
1823 		lv = sizeof(u64);
1824 		if (len != lv)
1825 			return -EINVAL;
1826 		v.val64 = sock_net(sk)->net_cookie;
1827 		break;
1828 
1829 	case SO_BUF_LOCK:
1830 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1831 		break;
1832 
1833 	case SO_RESERVE_MEM:
1834 		v.val = sk->sk_reserved_mem;
1835 		break;
1836 
1837 	default:
1838 		/* We implement the SO_SNDLOWAT etc to not be settable
1839 		 * (1003.1g 7).
1840 		 */
1841 		return -ENOPROTOOPT;
1842 	}
1843 
1844 	if (len > lv)
1845 		len = lv;
1846 	if (copy_to_user(optval, &v, len))
1847 		return -EFAULT;
1848 lenout:
1849 	if (put_user(len, optlen))
1850 		return -EFAULT;
1851 	return 0;
1852 }
1853 
1854 /*
1855  * Initialize an sk_lock.
1856  *
1857  * (We also register the sk_lock with the lock validator.)
1858  */
1859 static inline void sock_lock_init(struct sock *sk)
1860 {
1861 	if (sk->sk_kern_sock)
1862 		sock_lock_init_class_and_name(
1863 			sk,
1864 			af_family_kern_slock_key_strings[sk->sk_family],
1865 			af_family_kern_slock_keys + sk->sk_family,
1866 			af_family_kern_key_strings[sk->sk_family],
1867 			af_family_kern_keys + sk->sk_family);
1868 	else
1869 		sock_lock_init_class_and_name(
1870 			sk,
1871 			af_family_slock_key_strings[sk->sk_family],
1872 			af_family_slock_keys + sk->sk_family,
1873 			af_family_key_strings[sk->sk_family],
1874 			af_family_keys + sk->sk_family);
1875 }
1876 
1877 /*
1878  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1879  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1880  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1881  */
1882 static void sock_copy(struct sock *nsk, const struct sock *osk)
1883 {
1884 	const struct proto *prot = READ_ONCE(osk->sk_prot);
1885 #ifdef CONFIG_SECURITY_NETWORK
1886 	void *sptr = nsk->sk_security;
1887 #endif
1888 
1889 	/* If we move sk_tx_queue_mapping out of the private section,
1890 	 * we must check if sk_tx_queue_clear() is called after
1891 	 * sock_copy() in sk_clone_lock().
1892 	 */
1893 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
1894 		     offsetof(struct sock, sk_dontcopy_begin) ||
1895 		     offsetof(struct sock, sk_tx_queue_mapping) >=
1896 		     offsetof(struct sock, sk_dontcopy_end));
1897 
1898 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1899 
1900 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1901 	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1902 
1903 #ifdef CONFIG_SECURITY_NETWORK
1904 	nsk->sk_security = sptr;
1905 	security_sk_clone(osk, nsk);
1906 #endif
1907 }
1908 
1909 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1910 		int family)
1911 {
1912 	struct sock *sk;
1913 	struct kmem_cache *slab;
1914 
1915 	slab = prot->slab;
1916 	if (slab != NULL) {
1917 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1918 		if (!sk)
1919 			return sk;
1920 		if (want_init_on_alloc(priority))
1921 			sk_prot_clear_nulls(sk, prot->obj_size);
1922 	} else
1923 		sk = kmalloc(prot->obj_size, priority);
1924 
1925 	if (sk != NULL) {
1926 		if (security_sk_alloc(sk, family, priority))
1927 			goto out_free;
1928 
1929 		if (!try_module_get(prot->owner))
1930 			goto out_free_sec;
1931 	}
1932 
1933 	return sk;
1934 
1935 out_free_sec:
1936 	security_sk_free(sk);
1937 out_free:
1938 	if (slab != NULL)
1939 		kmem_cache_free(slab, sk);
1940 	else
1941 		kfree(sk);
1942 	return NULL;
1943 }
1944 
1945 static void sk_prot_free(struct proto *prot, struct sock *sk)
1946 {
1947 	struct kmem_cache *slab;
1948 	struct module *owner;
1949 
1950 	owner = prot->owner;
1951 	slab = prot->slab;
1952 
1953 	cgroup_sk_free(&sk->sk_cgrp_data);
1954 	mem_cgroup_sk_free(sk);
1955 	security_sk_free(sk);
1956 	if (slab != NULL)
1957 		kmem_cache_free(slab, sk);
1958 	else
1959 		kfree(sk);
1960 	module_put(owner);
1961 }
1962 
1963 /**
1964  *	sk_alloc - All socket objects are allocated here
1965  *	@net: the applicable net namespace
1966  *	@family: protocol family
1967  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1968  *	@prot: struct proto associated with this new sock instance
1969  *	@kern: is this to be a kernel socket?
1970  */
1971 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1972 		      struct proto *prot, int kern)
1973 {
1974 	struct sock *sk;
1975 
1976 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1977 	if (sk) {
1978 		sk->sk_family = family;
1979 		/*
1980 		 * See comment in struct sock definition to understand
1981 		 * why we need sk_prot_creator -acme
1982 		 */
1983 		sk->sk_prot = sk->sk_prot_creator = prot;
1984 		sk->sk_kern_sock = kern;
1985 		sock_lock_init(sk);
1986 		sk->sk_net_refcnt = kern ? 0 : 1;
1987 		if (likely(sk->sk_net_refcnt)) {
1988 			get_net_track(net, &sk->ns_tracker, priority);
1989 			sock_inuse_add(net, 1);
1990 		}
1991 
1992 		sock_net_set(sk, net);
1993 		refcount_set(&sk->sk_wmem_alloc, 1);
1994 
1995 		mem_cgroup_sk_alloc(sk);
1996 		cgroup_sk_alloc(&sk->sk_cgrp_data);
1997 		sock_update_classid(&sk->sk_cgrp_data);
1998 		sock_update_netprioidx(&sk->sk_cgrp_data);
1999 		sk_tx_queue_clear(sk);
2000 	}
2001 
2002 	return sk;
2003 }
2004 EXPORT_SYMBOL(sk_alloc);
2005 
2006 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2007  * grace period. This is the case for UDP sockets and TCP listeners.
2008  */
2009 static void __sk_destruct(struct rcu_head *head)
2010 {
2011 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2012 	struct sk_filter *filter;
2013 
2014 	if (sk->sk_destruct)
2015 		sk->sk_destruct(sk);
2016 
2017 	filter = rcu_dereference_check(sk->sk_filter,
2018 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2019 	if (filter) {
2020 		sk_filter_uncharge(sk, filter);
2021 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2022 	}
2023 
2024 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2025 
2026 #ifdef CONFIG_BPF_SYSCALL
2027 	bpf_sk_storage_free(sk);
2028 #endif
2029 
2030 	if (atomic_read(&sk->sk_omem_alloc))
2031 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2032 			 __func__, atomic_read(&sk->sk_omem_alloc));
2033 
2034 	if (sk->sk_frag.page) {
2035 		put_page(sk->sk_frag.page);
2036 		sk->sk_frag.page = NULL;
2037 	}
2038 
2039 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2040 	put_cred(sk->sk_peer_cred);
2041 	put_pid(sk->sk_peer_pid);
2042 
2043 	if (likely(sk->sk_net_refcnt))
2044 		put_net_track(sock_net(sk), &sk->ns_tracker);
2045 	sk_prot_free(sk->sk_prot_creator, sk);
2046 }
2047 
2048 void sk_destruct(struct sock *sk)
2049 {
2050 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2051 
2052 	WARN_ON_ONCE(!llist_empty(&sk->defer_list));
2053 	sk_defer_free_flush(sk);
2054 
2055 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2056 		reuseport_detach_sock(sk);
2057 		use_call_rcu = true;
2058 	}
2059 
2060 	if (use_call_rcu)
2061 		call_rcu(&sk->sk_rcu, __sk_destruct);
2062 	else
2063 		__sk_destruct(&sk->sk_rcu);
2064 }
2065 
2066 static void __sk_free(struct sock *sk)
2067 {
2068 	if (likely(sk->sk_net_refcnt))
2069 		sock_inuse_add(sock_net(sk), -1);
2070 
2071 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2072 		sock_diag_broadcast_destroy(sk);
2073 	else
2074 		sk_destruct(sk);
2075 }
2076 
2077 void sk_free(struct sock *sk)
2078 {
2079 	/*
2080 	 * We subtract one from sk_wmem_alloc and can know if
2081 	 * some packets are still in some tx queue.
2082 	 * If not null, sock_wfree() will call __sk_free(sk) later
2083 	 */
2084 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2085 		__sk_free(sk);
2086 }
2087 EXPORT_SYMBOL(sk_free);
2088 
2089 static void sk_init_common(struct sock *sk)
2090 {
2091 	skb_queue_head_init(&sk->sk_receive_queue);
2092 	skb_queue_head_init(&sk->sk_write_queue);
2093 	skb_queue_head_init(&sk->sk_error_queue);
2094 
2095 	rwlock_init(&sk->sk_callback_lock);
2096 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2097 			af_rlock_keys + sk->sk_family,
2098 			af_family_rlock_key_strings[sk->sk_family]);
2099 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2100 			af_wlock_keys + sk->sk_family,
2101 			af_family_wlock_key_strings[sk->sk_family]);
2102 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2103 			af_elock_keys + sk->sk_family,
2104 			af_family_elock_key_strings[sk->sk_family]);
2105 	lockdep_set_class_and_name(&sk->sk_callback_lock,
2106 			af_callback_keys + sk->sk_family,
2107 			af_family_clock_key_strings[sk->sk_family]);
2108 }
2109 
2110 /**
2111  *	sk_clone_lock - clone a socket, and lock its clone
2112  *	@sk: the socket to clone
2113  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2114  *
2115  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2116  */
2117 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2118 {
2119 	struct proto *prot = READ_ONCE(sk->sk_prot);
2120 	struct sk_filter *filter;
2121 	bool is_charged = true;
2122 	struct sock *newsk;
2123 
2124 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2125 	if (!newsk)
2126 		goto out;
2127 
2128 	sock_copy(newsk, sk);
2129 
2130 	newsk->sk_prot_creator = prot;
2131 
2132 	/* SANITY */
2133 	if (likely(newsk->sk_net_refcnt)) {
2134 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2135 		sock_inuse_add(sock_net(newsk), 1);
2136 	}
2137 	sk_node_init(&newsk->sk_node);
2138 	sock_lock_init(newsk);
2139 	bh_lock_sock(newsk);
2140 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2141 	newsk->sk_backlog.len = 0;
2142 
2143 	atomic_set(&newsk->sk_rmem_alloc, 0);
2144 
2145 	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2146 	refcount_set(&newsk->sk_wmem_alloc, 1);
2147 
2148 	atomic_set(&newsk->sk_omem_alloc, 0);
2149 	sk_init_common(newsk);
2150 
2151 	newsk->sk_dst_cache	= NULL;
2152 	newsk->sk_dst_pending_confirm = 0;
2153 	newsk->sk_wmem_queued	= 0;
2154 	newsk->sk_forward_alloc = 0;
2155 	newsk->sk_reserved_mem  = 0;
2156 	atomic_set(&newsk->sk_drops, 0);
2157 	newsk->sk_send_head	= NULL;
2158 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2159 	atomic_set(&newsk->sk_zckey, 0);
2160 
2161 	sock_reset_flag(newsk, SOCK_DONE);
2162 
2163 	/* sk->sk_memcg will be populated at accept() time */
2164 	newsk->sk_memcg = NULL;
2165 
2166 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2167 
2168 	rcu_read_lock();
2169 	filter = rcu_dereference(sk->sk_filter);
2170 	if (filter != NULL)
2171 		/* though it's an empty new sock, the charging may fail
2172 		 * if sysctl_optmem_max was changed between creation of
2173 		 * original socket and cloning
2174 		 */
2175 		is_charged = sk_filter_charge(newsk, filter);
2176 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2177 	rcu_read_unlock();
2178 
2179 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2180 		/* We need to make sure that we don't uncharge the new
2181 		 * socket if we couldn't charge it in the first place
2182 		 * as otherwise we uncharge the parent's filter.
2183 		 */
2184 		if (!is_charged)
2185 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2186 		sk_free_unlock_clone(newsk);
2187 		newsk = NULL;
2188 		goto out;
2189 	}
2190 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2191 
2192 	if (bpf_sk_storage_clone(sk, newsk)) {
2193 		sk_free_unlock_clone(newsk);
2194 		newsk = NULL;
2195 		goto out;
2196 	}
2197 
2198 	/* Clear sk_user_data if parent had the pointer tagged
2199 	 * as not suitable for copying when cloning.
2200 	 */
2201 	if (sk_user_data_is_nocopy(newsk))
2202 		newsk->sk_user_data = NULL;
2203 
2204 	newsk->sk_err	   = 0;
2205 	newsk->sk_err_soft = 0;
2206 	newsk->sk_priority = 0;
2207 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2208 
2209 	/* Before updating sk_refcnt, we must commit prior changes to memory
2210 	 * (Documentation/RCU/rculist_nulls.rst for details)
2211 	 */
2212 	smp_wmb();
2213 	refcount_set(&newsk->sk_refcnt, 2);
2214 
2215 	/* Increment the counter in the same struct proto as the master
2216 	 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
2217 	 * is the same as sk->sk_prot->socks, as this field was copied
2218 	 * with memcpy).
2219 	 *
2220 	 * This _changes_ the previous behaviour, where
2221 	 * tcp_create_openreq_child always was incrementing the
2222 	 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
2223 	 * to be taken into account in all callers. -acme
2224 	 */
2225 	sk_refcnt_debug_inc(newsk);
2226 	sk_set_socket(newsk, NULL);
2227 	sk_tx_queue_clear(newsk);
2228 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2229 
2230 	if (newsk->sk_prot->sockets_allocated)
2231 		sk_sockets_allocated_inc(newsk);
2232 
2233 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2234 		net_enable_timestamp();
2235 out:
2236 	return newsk;
2237 }
2238 EXPORT_SYMBOL_GPL(sk_clone_lock);
2239 
2240 void sk_free_unlock_clone(struct sock *sk)
2241 {
2242 	/* It is still raw copy of parent, so invalidate
2243 	 * destructor and make plain sk_free() */
2244 	sk->sk_destruct = NULL;
2245 	bh_unlock_sock(sk);
2246 	sk_free(sk);
2247 }
2248 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2249 
2250 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2251 {
2252 	u32 max_segs = 1;
2253 
2254 	sk_dst_set(sk, dst);
2255 	sk->sk_route_caps = dst->dev->features;
2256 	if (sk_is_tcp(sk))
2257 		sk->sk_route_caps |= NETIF_F_GSO;
2258 	if (sk->sk_route_caps & NETIF_F_GSO)
2259 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2260 	if (unlikely(sk->sk_gso_disabled))
2261 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2262 	if (sk_can_gso(sk)) {
2263 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2264 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2265 		} else {
2266 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2267 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_size() */
2268 			sk->sk_gso_max_size = READ_ONCE(dst->dev->gso_max_size);
2269 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2270 			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2271 		}
2272 	}
2273 	sk->sk_gso_max_segs = max_segs;
2274 }
2275 EXPORT_SYMBOL_GPL(sk_setup_caps);
2276 
2277 /*
2278  *	Simple resource managers for sockets.
2279  */
2280 
2281 
2282 /*
2283  * Write buffer destructor automatically called from kfree_skb.
2284  */
2285 void sock_wfree(struct sk_buff *skb)
2286 {
2287 	struct sock *sk = skb->sk;
2288 	unsigned int len = skb->truesize;
2289 
2290 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2291 		/*
2292 		 * Keep a reference on sk_wmem_alloc, this will be released
2293 		 * after sk_write_space() call
2294 		 */
2295 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2296 		sk->sk_write_space(sk);
2297 		len = 1;
2298 	}
2299 	/*
2300 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2301 	 * could not do because of in-flight packets
2302 	 */
2303 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2304 		__sk_free(sk);
2305 }
2306 EXPORT_SYMBOL(sock_wfree);
2307 
2308 /* This variant of sock_wfree() is used by TCP,
2309  * since it sets SOCK_USE_WRITE_QUEUE.
2310  */
2311 void __sock_wfree(struct sk_buff *skb)
2312 {
2313 	struct sock *sk = skb->sk;
2314 
2315 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2316 		__sk_free(sk);
2317 }
2318 
2319 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2320 {
2321 	skb_orphan(skb);
2322 	skb->sk = sk;
2323 #ifdef CONFIG_INET
2324 	if (unlikely(!sk_fullsock(sk))) {
2325 		skb->destructor = sock_edemux;
2326 		sock_hold(sk);
2327 		return;
2328 	}
2329 #endif
2330 	skb->destructor = sock_wfree;
2331 	skb_set_hash_from_sk(skb, sk);
2332 	/*
2333 	 * We used to take a refcount on sk, but following operation
2334 	 * is enough to guarantee sk_free() wont free this sock until
2335 	 * all in-flight packets are completed
2336 	 */
2337 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2338 }
2339 EXPORT_SYMBOL(skb_set_owner_w);
2340 
2341 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2342 {
2343 #ifdef CONFIG_TLS_DEVICE
2344 	/* Drivers depend on in-order delivery for crypto offload,
2345 	 * partial orphan breaks out-of-order-OK logic.
2346 	 */
2347 	if (skb->decrypted)
2348 		return false;
2349 #endif
2350 	return (skb->destructor == sock_wfree ||
2351 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2352 }
2353 
2354 /* This helper is used by netem, as it can hold packets in its
2355  * delay queue. We want to allow the owner socket to send more
2356  * packets, as if they were already TX completed by a typical driver.
2357  * But we also want to keep skb->sk set because some packet schedulers
2358  * rely on it (sch_fq for example).
2359  */
2360 void skb_orphan_partial(struct sk_buff *skb)
2361 {
2362 	if (skb_is_tcp_pure_ack(skb))
2363 		return;
2364 
2365 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2366 		return;
2367 
2368 	skb_orphan(skb);
2369 }
2370 EXPORT_SYMBOL(skb_orphan_partial);
2371 
2372 /*
2373  * Read buffer destructor automatically called from kfree_skb.
2374  */
2375 void sock_rfree(struct sk_buff *skb)
2376 {
2377 	struct sock *sk = skb->sk;
2378 	unsigned int len = skb->truesize;
2379 
2380 	atomic_sub(len, &sk->sk_rmem_alloc);
2381 	sk_mem_uncharge(sk, len);
2382 }
2383 EXPORT_SYMBOL(sock_rfree);
2384 
2385 /*
2386  * Buffer destructor for skbs that are not used directly in read or write
2387  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2388  */
2389 void sock_efree(struct sk_buff *skb)
2390 {
2391 	sock_put(skb->sk);
2392 }
2393 EXPORT_SYMBOL(sock_efree);
2394 
2395 /* Buffer destructor for prefetch/receive path where reference count may
2396  * not be held, e.g. for listen sockets.
2397  */
2398 #ifdef CONFIG_INET
2399 void sock_pfree(struct sk_buff *skb)
2400 {
2401 	if (sk_is_refcounted(skb->sk))
2402 		sock_gen_put(skb->sk);
2403 }
2404 EXPORT_SYMBOL(sock_pfree);
2405 #endif /* CONFIG_INET */
2406 
2407 kuid_t sock_i_uid(struct sock *sk)
2408 {
2409 	kuid_t uid;
2410 
2411 	read_lock_bh(&sk->sk_callback_lock);
2412 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2413 	read_unlock_bh(&sk->sk_callback_lock);
2414 	return uid;
2415 }
2416 EXPORT_SYMBOL(sock_i_uid);
2417 
2418 unsigned long sock_i_ino(struct sock *sk)
2419 {
2420 	unsigned long ino;
2421 
2422 	read_lock_bh(&sk->sk_callback_lock);
2423 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2424 	read_unlock_bh(&sk->sk_callback_lock);
2425 	return ino;
2426 }
2427 EXPORT_SYMBOL(sock_i_ino);
2428 
2429 /*
2430  * Allocate a skb from the socket's send buffer.
2431  */
2432 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2433 			     gfp_t priority)
2434 {
2435 	if (force ||
2436 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2437 		struct sk_buff *skb = alloc_skb(size, priority);
2438 
2439 		if (skb) {
2440 			skb_set_owner_w(skb, sk);
2441 			return skb;
2442 		}
2443 	}
2444 	return NULL;
2445 }
2446 EXPORT_SYMBOL(sock_wmalloc);
2447 
2448 static void sock_ofree(struct sk_buff *skb)
2449 {
2450 	struct sock *sk = skb->sk;
2451 
2452 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2453 }
2454 
2455 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2456 			     gfp_t priority)
2457 {
2458 	struct sk_buff *skb;
2459 
2460 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2461 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2462 	    sysctl_optmem_max)
2463 		return NULL;
2464 
2465 	skb = alloc_skb(size, priority);
2466 	if (!skb)
2467 		return NULL;
2468 
2469 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2470 	skb->sk = sk;
2471 	skb->destructor = sock_ofree;
2472 	return skb;
2473 }
2474 
2475 /*
2476  * Allocate a memory block from the socket's option memory buffer.
2477  */
2478 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2479 {
2480 	if ((unsigned int)size <= sysctl_optmem_max &&
2481 	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
2482 		void *mem;
2483 		/* First do the add, to avoid the race if kmalloc
2484 		 * might sleep.
2485 		 */
2486 		atomic_add(size, &sk->sk_omem_alloc);
2487 		mem = kmalloc(size, priority);
2488 		if (mem)
2489 			return mem;
2490 		atomic_sub(size, &sk->sk_omem_alloc);
2491 	}
2492 	return NULL;
2493 }
2494 EXPORT_SYMBOL(sock_kmalloc);
2495 
2496 /* Free an option memory block. Note, we actually want the inline
2497  * here as this allows gcc to detect the nullify and fold away the
2498  * condition entirely.
2499  */
2500 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2501 				  const bool nullify)
2502 {
2503 	if (WARN_ON_ONCE(!mem))
2504 		return;
2505 	if (nullify)
2506 		kfree_sensitive(mem);
2507 	else
2508 		kfree(mem);
2509 	atomic_sub(size, &sk->sk_omem_alloc);
2510 }
2511 
2512 void sock_kfree_s(struct sock *sk, void *mem, int size)
2513 {
2514 	__sock_kfree_s(sk, mem, size, false);
2515 }
2516 EXPORT_SYMBOL(sock_kfree_s);
2517 
2518 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2519 {
2520 	__sock_kfree_s(sk, mem, size, true);
2521 }
2522 EXPORT_SYMBOL(sock_kzfree_s);
2523 
2524 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2525    I think, these locks should be removed for datagram sockets.
2526  */
2527 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2528 {
2529 	DEFINE_WAIT(wait);
2530 
2531 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2532 	for (;;) {
2533 		if (!timeo)
2534 			break;
2535 		if (signal_pending(current))
2536 			break;
2537 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2538 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2539 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2540 			break;
2541 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2542 			break;
2543 		if (sk->sk_err)
2544 			break;
2545 		timeo = schedule_timeout(timeo);
2546 	}
2547 	finish_wait(sk_sleep(sk), &wait);
2548 	return timeo;
2549 }
2550 
2551 
2552 /*
2553  *	Generic send/receive buffer handlers
2554  */
2555 
2556 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2557 				     unsigned long data_len, int noblock,
2558 				     int *errcode, int max_page_order)
2559 {
2560 	struct sk_buff *skb;
2561 	long timeo;
2562 	int err;
2563 
2564 	timeo = sock_sndtimeo(sk, noblock);
2565 	for (;;) {
2566 		err = sock_error(sk);
2567 		if (err != 0)
2568 			goto failure;
2569 
2570 		err = -EPIPE;
2571 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2572 			goto failure;
2573 
2574 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2575 			break;
2576 
2577 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2578 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2579 		err = -EAGAIN;
2580 		if (!timeo)
2581 			goto failure;
2582 		if (signal_pending(current))
2583 			goto interrupted;
2584 		timeo = sock_wait_for_wmem(sk, timeo);
2585 	}
2586 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2587 				   errcode, sk->sk_allocation);
2588 	if (skb)
2589 		skb_set_owner_w(skb, sk);
2590 	return skb;
2591 
2592 interrupted:
2593 	err = sock_intr_errno(timeo);
2594 failure:
2595 	*errcode = err;
2596 	return NULL;
2597 }
2598 EXPORT_SYMBOL(sock_alloc_send_pskb);
2599 
2600 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2601 				    int noblock, int *errcode)
2602 {
2603 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2604 }
2605 EXPORT_SYMBOL(sock_alloc_send_skb);
2606 
2607 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2608 		     struct sockcm_cookie *sockc)
2609 {
2610 	u32 tsflags;
2611 
2612 	switch (cmsg->cmsg_type) {
2613 	case SO_MARK:
2614 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2615 			return -EPERM;
2616 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2617 			return -EINVAL;
2618 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2619 		break;
2620 	case SO_TIMESTAMPING_OLD:
2621 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2622 			return -EINVAL;
2623 
2624 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2625 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2626 			return -EINVAL;
2627 
2628 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2629 		sockc->tsflags |= tsflags;
2630 		break;
2631 	case SCM_TXTIME:
2632 		if (!sock_flag(sk, SOCK_TXTIME))
2633 			return -EINVAL;
2634 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2635 			return -EINVAL;
2636 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2637 		break;
2638 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2639 	case SCM_RIGHTS:
2640 	case SCM_CREDENTIALS:
2641 		break;
2642 	default:
2643 		return -EINVAL;
2644 	}
2645 	return 0;
2646 }
2647 EXPORT_SYMBOL(__sock_cmsg_send);
2648 
2649 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2650 		   struct sockcm_cookie *sockc)
2651 {
2652 	struct cmsghdr *cmsg;
2653 	int ret;
2654 
2655 	for_each_cmsghdr(cmsg, msg) {
2656 		if (!CMSG_OK(msg, cmsg))
2657 			return -EINVAL;
2658 		if (cmsg->cmsg_level != SOL_SOCKET)
2659 			continue;
2660 		ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2661 		if (ret)
2662 			return ret;
2663 	}
2664 	return 0;
2665 }
2666 EXPORT_SYMBOL(sock_cmsg_send);
2667 
2668 static void sk_enter_memory_pressure(struct sock *sk)
2669 {
2670 	if (!sk->sk_prot->enter_memory_pressure)
2671 		return;
2672 
2673 	sk->sk_prot->enter_memory_pressure(sk);
2674 }
2675 
2676 static void sk_leave_memory_pressure(struct sock *sk)
2677 {
2678 	if (sk->sk_prot->leave_memory_pressure) {
2679 		sk->sk_prot->leave_memory_pressure(sk);
2680 	} else {
2681 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2682 
2683 		if (memory_pressure && READ_ONCE(*memory_pressure))
2684 			WRITE_ONCE(*memory_pressure, 0);
2685 	}
2686 }
2687 
2688 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2689 
2690 /**
2691  * skb_page_frag_refill - check that a page_frag contains enough room
2692  * @sz: minimum size of the fragment we want to get
2693  * @pfrag: pointer to page_frag
2694  * @gfp: priority for memory allocation
2695  *
2696  * Note: While this allocator tries to use high order pages, there is
2697  * no guarantee that allocations succeed. Therefore, @sz MUST be
2698  * less or equal than PAGE_SIZE.
2699  */
2700 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2701 {
2702 	if (pfrag->page) {
2703 		if (page_ref_count(pfrag->page) == 1) {
2704 			pfrag->offset = 0;
2705 			return true;
2706 		}
2707 		if (pfrag->offset + sz <= pfrag->size)
2708 			return true;
2709 		put_page(pfrag->page);
2710 	}
2711 
2712 	pfrag->offset = 0;
2713 	if (SKB_FRAG_PAGE_ORDER &&
2714 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2715 		/* Avoid direct reclaim but allow kswapd to wake */
2716 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2717 					  __GFP_COMP | __GFP_NOWARN |
2718 					  __GFP_NORETRY,
2719 					  SKB_FRAG_PAGE_ORDER);
2720 		if (likely(pfrag->page)) {
2721 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2722 			return true;
2723 		}
2724 	}
2725 	pfrag->page = alloc_page(gfp);
2726 	if (likely(pfrag->page)) {
2727 		pfrag->size = PAGE_SIZE;
2728 		return true;
2729 	}
2730 	return false;
2731 }
2732 EXPORT_SYMBOL(skb_page_frag_refill);
2733 
2734 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2735 {
2736 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2737 		return true;
2738 
2739 	sk_enter_memory_pressure(sk);
2740 	sk_stream_moderate_sndbuf(sk);
2741 	return false;
2742 }
2743 EXPORT_SYMBOL(sk_page_frag_refill);
2744 
2745 void __lock_sock(struct sock *sk)
2746 	__releases(&sk->sk_lock.slock)
2747 	__acquires(&sk->sk_lock.slock)
2748 {
2749 	DEFINE_WAIT(wait);
2750 
2751 	for (;;) {
2752 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2753 					TASK_UNINTERRUPTIBLE);
2754 		spin_unlock_bh(&sk->sk_lock.slock);
2755 		schedule();
2756 		spin_lock_bh(&sk->sk_lock.slock);
2757 		if (!sock_owned_by_user(sk))
2758 			break;
2759 	}
2760 	finish_wait(&sk->sk_lock.wq, &wait);
2761 }
2762 
2763 void __release_sock(struct sock *sk)
2764 	__releases(&sk->sk_lock.slock)
2765 	__acquires(&sk->sk_lock.slock)
2766 {
2767 	struct sk_buff *skb, *next;
2768 
2769 	while ((skb = sk->sk_backlog.head) != NULL) {
2770 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2771 
2772 		spin_unlock_bh(&sk->sk_lock.slock);
2773 
2774 		do {
2775 			next = skb->next;
2776 			prefetch(next);
2777 			WARN_ON_ONCE(skb_dst_is_noref(skb));
2778 			skb_mark_not_on_list(skb);
2779 			sk_backlog_rcv(sk, skb);
2780 
2781 			cond_resched();
2782 
2783 			skb = next;
2784 		} while (skb != NULL);
2785 
2786 		spin_lock_bh(&sk->sk_lock.slock);
2787 	}
2788 
2789 	/*
2790 	 * Doing the zeroing here guarantee we can not loop forever
2791 	 * while a wild producer attempts to flood us.
2792 	 */
2793 	sk->sk_backlog.len = 0;
2794 }
2795 
2796 void __sk_flush_backlog(struct sock *sk)
2797 {
2798 	spin_lock_bh(&sk->sk_lock.slock);
2799 	__release_sock(sk);
2800 	spin_unlock_bh(&sk->sk_lock.slock);
2801 }
2802 
2803 /**
2804  * sk_wait_data - wait for data to arrive at sk_receive_queue
2805  * @sk:    sock to wait on
2806  * @timeo: for how long
2807  * @skb:   last skb seen on sk_receive_queue
2808  *
2809  * Now socket state including sk->sk_err is changed only under lock,
2810  * hence we may omit checks after joining wait queue.
2811  * We check receive queue before schedule() only as optimization;
2812  * it is very likely that release_sock() added new data.
2813  */
2814 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2815 {
2816 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2817 	int rc;
2818 
2819 	add_wait_queue(sk_sleep(sk), &wait);
2820 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2821 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2822 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2823 	remove_wait_queue(sk_sleep(sk), &wait);
2824 	return rc;
2825 }
2826 EXPORT_SYMBOL(sk_wait_data);
2827 
2828 /**
2829  *	__sk_mem_raise_allocated - increase memory_allocated
2830  *	@sk: socket
2831  *	@size: memory size to allocate
2832  *	@amt: pages to allocate
2833  *	@kind: allocation type
2834  *
2835  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2836  */
2837 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2838 {
2839 	struct proto *prot = sk->sk_prot;
2840 	long allocated = sk_memory_allocated_add(sk, amt);
2841 	bool memcg_charge = mem_cgroup_sockets_enabled && sk->sk_memcg;
2842 	bool charged = true;
2843 
2844 	if (memcg_charge &&
2845 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt,
2846 						gfp_memcg_charge())))
2847 		goto suppress_allocation;
2848 
2849 	/* Under limit. */
2850 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2851 		sk_leave_memory_pressure(sk);
2852 		return 1;
2853 	}
2854 
2855 	/* Under pressure. */
2856 	if (allocated > sk_prot_mem_limits(sk, 1))
2857 		sk_enter_memory_pressure(sk);
2858 
2859 	/* Over hard limit. */
2860 	if (allocated > sk_prot_mem_limits(sk, 2))
2861 		goto suppress_allocation;
2862 
2863 	/* guarantee minimum buffer size under pressure */
2864 	if (kind == SK_MEM_RECV) {
2865 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2866 			return 1;
2867 
2868 	} else { /* SK_MEM_SEND */
2869 		int wmem0 = sk_get_wmem0(sk, prot);
2870 
2871 		if (sk->sk_type == SOCK_STREAM) {
2872 			if (sk->sk_wmem_queued < wmem0)
2873 				return 1;
2874 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
2875 				return 1;
2876 		}
2877 	}
2878 
2879 	if (sk_has_memory_pressure(sk)) {
2880 		u64 alloc;
2881 
2882 		if (!sk_under_memory_pressure(sk))
2883 			return 1;
2884 		alloc = sk_sockets_allocated_read_positive(sk);
2885 		if (sk_prot_mem_limits(sk, 2) > alloc *
2886 		    sk_mem_pages(sk->sk_wmem_queued +
2887 				 atomic_read(&sk->sk_rmem_alloc) +
2888 				 sk->sk_forward_alloc))
2889 			return 1;
2890 	}
2891 
2892 suppress_allocation:
2893 
2894 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2895 		sk_stream_moderate_sndbuf(sk);
2896 
2897 		/* Fail only if socket is _under_ its sndbuf.
2898 		 * In this case we cannot block, so that we have to fail.
2899 		 */
2900 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
2901 			/* Force charge with __GFP_NOFAIL */
2902 			if (memcg_charge && !charged) {
2903 				mem_cgroup_charge_skmem(sk->sk_memcg, amt,
2904 					gfp_memcg_charge() | __GFP_NOFAIL);
2905 			}
2906 			return 1;
2907 		}
2908 	}
2909 
2910 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
2911 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
2912 
2913 	sk_memory_allocated_sub(sk, amt);
2914 
2915 	if (memcg_charge && charged)
2916 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2917 
2918 	return 0;
2919 }
2920 EXPORT_SYMBOL(__sk_mem_raise_allocated);
2921 
2922 /**
2923  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2924  *	@sk: socket
2925  *	@size: memory size to allocate
2926  *	@kind: allocation type
2927  *
2928  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2929  *	rmem allocation. This function assumes that protocols which have
2930  *	memory_pressure use sk_wmem_queued as write buffer accounting.
2931  */
2932 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2933 {
2934 	int ret, amt = sk_mem_pages(size);
2935 
2936 	sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2937 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2938 	if (!ret)
2939 		sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2940 	return ret;
2941 }
2942 EXPORT_SYMBOL(__sk_mem_schedule);
2943 
2944 /**
2945  *	__sk_mem_reduce_allocated - reclaim memory_allocated
2946  *	@sk: socket
2947  *	@amount: number of quanta
2948  *
2949  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2950  */
2951 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2952 {
2953 	sk_memory_allocated_sub(sk, amount);
2954 
2955 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2956 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2957 
2958 	if (sk_under_memory_pressure(sk) &&
2959 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2960 		sk_leave_memory_pressure(sk);
2961 }
2962 EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2963 
2964 /**
2965  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2966  *	@sk: socket
2967  *	@amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2968  */
2969 void __sk_mem_reclaim(struct sock *sk, int amount)
2970 {
2971 	amount >>= SK_MEM_QUANTUM_SHIFT;
2972 	sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2973 	__sk_mem_reduce_allocated(sk, amount);
2974 }
2975 EXPORT_SYMBOL(__sk_mem_reclaim);
2976 
2977 int sk_set_peek_off(struct sock *sk, int val)
2978 {
2979 	sk->sk_peek_off = val;
2980 	return 0;
2981 }
2982 EXPORT_SYMBOL_GPL(sk_set_peek_off);
2983 
2984 /*
2985  * Set of default routines for initialising struct proto_ops when
2986  * the protocol does not support a particular function. In certain
2987  * cases where it makes no sense for a protocol to have a "do nothing"
2988  * function, some default processing is provided.
2989  */
2990 
2991 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2992 {
2993 	return -EOPNOTSUPP;
2994 }
2995 EXPORT_SYMBOL(sock_no_bind);
2996 
2997 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2998 		    int len, int flags)
2999 {
3000 	return -EOPNOTSUPP;
3001 }
3002 EXPORT_SYMBOL(sock_no_connect);
3003 
3004 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3005 {
3006 	return -EOPNOTSUPP;
3007 }
3008 EXPORT_SYMBOL(sock_no_socketpair);
3009 
3010 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3011 		   bool kern)
3012 {
3013 	return -EOPNOTSUPP;
3014 }
3015 EXPORT_SYMBOL(sock_no_accept);
3016 
3017 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3018 		    int peer)
3019 {
3020 	return -EOPNOTSUPP;
3021 }
3022 EXPORT_SYMBOL(sock_no_getname);
3023 
3024 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3025 {
3026 	return -EOPNOTSUPP;
3027 }
3028 EXPORT_SYMBOL(sock_no_ioctl);
3029 
3030 int sock_no_listen(struct socket *sock, int backlog)
3031 {
3032 	return -EOPNOTSUPP;
3033 }
3034 EXPORT_SYMBOL(sock_no_listen);
3035 
3036 int sock_no_shutdown(struct socket *sock, int how)
3037 {
3038 	return -EOPNOTSUPP;
3039 }
3040 EXPORT_SYMBOL(sock_no_shutdown);
3041 
3042 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3043 {
3044 	return -EOPNOTSUPP;
3045 }
3046 EXPORT_SYMBOL(sock_no_sendmsg);
3047 
3048 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3049 {
3050 	return -EOPNOTSUPP;
3051 }
3052 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3053 
3054 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3055 		    int flags)
3056 {
3057 	return -EOPNOTSUPP;
3058 }
3059 EXPORT_SYMBOL(sock_no_recvmsg);
3060 
3061 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3062 {
3063 	/* Mirror missing mmap method error code */
3064 	return -ENODEV;
3065 }
3066 EXPORT_SYMBOL(sock_no_mmap);
3067 
3068 /*
3069  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3070  * various sock-based usage counts.
3071  */
3072 void __receive_sock(struct file *file)
3073 {
3074 	struct socket *sock;
3075 
3076 	sock = sock_from_file(file);
3077 	if (sock) {
3078 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3079 		sock_update_classid(&sock->sk->sk_cgrp_data);
3080 	}
3081 }
3082 
3083 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
3084 {
3085 	ssize_t res;
3086 	struct msghdr msg = {.msg_flags = flags};
3087 	struct kvec iov;
3088 	char *kaddr = kmap(page);
3089 	iov.iov_base = kaddr + offset;
3090 	iov.iov_len = size;
3091 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
3092 	kunmap(page);
3093 	return res;
3094 }
3095 EXPORT_SYMBOL(sock_no_sendpage);
3096 
3097 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
3098 				int offset, size_t size, int flags)
3099 {
3100 	ssize_t res;
3101 	struct msghdr msg = {.msg_flags = flags};
3102 	struct kvec iov;
3103 	char *kaddr = kmap(page);
3104 
3105 	iov.iov_base = kaddr + offset;
3106 	iov.iov_len = size;
3107 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
3108 	kunmap(page);
3109 	return res;
3110 }
3111 EXPORT_SYMBOL(sock_no_sendpage_locked);
3112 
3113 /*
3114  *	Default Socket Callbacks
3115  */
3116 
3117 static void sock_def_wakeup(struct sock *sk)
3118 {
3119 	struct socket_wq *wq;
3120 
3121 	rcu_read_lock();
3122 	wq = rcu_dereference(sk->sk_wq);
3123 	if (skwq_has_sleeper(wq))
3124 		wake_up_interruptible_all(&wq->wait);
3125 	rcu_read_unlock();
3126 }
3127 
3128 static void sock_def_error_report(struct sock *sk)
3129 {
3130 	struct socket_wq *wq;
3131 
3132 	rcu_read_lock();
3133 	wq = rcu_dereference(sk->sk_wq);
3134 	if (skwq_has_sleeper(wq))
3135 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3136 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3137 	rcu_read_unlock();
3138 }
3139 
3140 void sock_def_readable(struct sock *sk)
3141 {
3142 	struct socket_wq *wq;
3143 
3144 	rcu_read_lock();
3145 	wq = rcu_dereference(sk->sk_wq);
3146 	if (skwq_has_sleeper(wq))
3147 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3148 						EPOLLRDNORM | EPOLLRDBAND);
3149 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3150 	rcu_read_unlock();
3151 }
3152 
3153 static void sock_def_write_space(struct sock *sk)
3154 {
3155 	struct socket_wq *wq;
3156 
3157 	rcu_read_lock();
3158 
3159 	/* Do not wake up a writer until he can make "significant"
3160 	 * progress.  --DaveM
3161 	 */
3162 	if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= READ_ONCE(sk->sk_sndbuf)) {
3163 		wq = rcu_dereference(sk->sk_wq);
3164 		if (skwq_has_sleeper(wq))
3165 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3166 						EPOLLWRNORM | EPOLLWRBAND);
3167 
3168 		/* Should agree with poll, otherwise some programs break */
3169 		if (sock_writeable(sk))
3170 			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3171 	}
3172 
3173 	rcu_read_unlock();
3174 }
3175 
3176 static void sock_def_destruct(struct sock *sk)
3177 {
3178 }
3179 
3180 void sk_send_sigurg(struct sock *sk)
3181 {
3182 	if (sk->sk_socket && sk->sk_socket->file)
3183 		if (send_sigurg(&sk->sk_socket->file->f_owner))
3184 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3185 }
3186 EXPORT_SYMBOL(sk_send_sigurg);
3187 
3188 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3189 		    unsigned long expires)
3190 {
3191 	if (!mod_timer(timer, expires))
3192 		sock_hold(sk);
3193 }
3194 EXPORT_SYMBOL(sk_reset_timer);
3195 
3196 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3197 {
3198 	if (del_timer(timer))
3199 		__sock_put(sk);
3200 }
3201 EXPORT_SYMBOL(sk_stop_timer);
3202 
3203 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3204 {
3205 	if (del_timer_sync(timer))
3206 		__sock_put(sk);
3207 }
3208 EXPORT_SYMBOL(sk_stop_timer_sync);
3209 
3210 void sock_init_data(struct socket *sock, struct sock *sk)
3211 {
3212 	sk_init_common(sk);
3213 	sk->sk_send_head	=	NULL;
3214 
3215 	timer_setup(&sk->sk_timer, NULL, 0);
3216 
3217 	sk->sk_allocation	=	GFP_KERNEL;
3218 	sk->sk_rcvbuf		=	sysctl_rmem_default;
3219 	sk->sk_sndbuf		=	sysctl_wmem_default;
3220 	sk->sk_state		=	TCP_CLOSE;
3221 	sk_set_socket(sk, sock);
3222 
3223 	sock_set_flag(sk, SOCK_ZAPPED);
3224 
3225 	if (sock) {
3226 		sk->sk_type	=	sock->type;
3227 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3228 		sock->sk	=	sk;
3229 		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
3230 	} else {
3231 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3232 		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
3233 	}
3234 
3235 	rwlock_init(&sk->sk_callback_lock);
3236 	if (sk->sk_kern_sock)
3237 		lockdep_set_class_and_name(
3238 			&sk->sk_callback_lock,
3239 			af_kern_callback_keys + sk->sk_family,
3240 			af_family_kern_clock_key_strings[sk->sk_family]);
3241 	else
3242 		lockdep_set_class_and_name(
3243 			&sk->sk_callback_lock,
3244 			af_callback_keys + sk->sk_family,
3245 			af_family_clock_key_strings[sk->sk_family]);
3246 
3247 	sk->sk_state_change	=	sock_def_wakeup;
3248 	sk->sk_data_ready	=	sock_def_readable;
3249 	sk->sk_write_space	=	sock_def_write_space;
3250 	sk->sk_error_report	=	sock_def_error_report;
3251 	sk->sk_destruct		=	sock_def_destruct;
3252 
3253 	sk->sk_frag.page	=	NULL;
3254 	sk->sk_frag.offset	=	0;
3255 	sk->sk_peek_off		=	-1;
3256 
3257 	sk->sk_peer_pid 	=	NULL;
3258 	sk->sk_peer_cred	=	NULL;
3259 	spin_lock_init(&sk->sk_peer_lock);
3260 
3261 	sk->sk_write_pending	=	0;
3262 	sk->sk_rcvlowat		=	1;
3263 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3264 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3265 
3266 	sk->sk_stamp = SK_DEFAULT_STAMP;
3267 #if BITS_PER_LONG==32
3268 	seqlock_init(&sk->sk_stamp_seq);
3269 #endif
3270 	atomic_set(&sk->sk_zckey, 0);
3271 
3272 #ifdef CONFIG_NET_RX_BUSY_POLL
3273 	sk->sk_napi_id		=	0;
3274 	sk->sk_ll_usec		=	sysctl_net_busy_read;
3275 #endif
3276 
3277 	sk->sk_max_pacing_rate = ~0UL;
3278 	sk->sk_pacing_rate = ~0UL;
3279 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3280 	sk->sk_incoming_cpu = -1;
3281 
3282 	sk_rx_queue_clear(sk);
3283 	/*
3284 	 * Before updating sk_refcnt, we must commit prior changes to memory
3285 	 * (Documentation/RCU/rculist_nulls.rst for details)
3286 	 */
3287 	smp_wmb();
3288 	refcount_set(&sk->sk_refcnt, 1);
3289 	atomic_set(&sk->sk_drops, 0);
3290 }
3291 EXPORT_SYMBOL(sock_init_data);
3292 
3293 void lock_sock_nested(struct sock *sk, int subclass)
3294 {
3295 	/* The sk_lock has mutex_lock() semantics here. */
3296 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3297 
3298 	might_sleep();
3299 	spin_lock_bh(&sk->sk_lock.slock);
3300 	if (sock_owned_by_user_nocheck(sk))
3301 		__lock_sock(sk);
3302 	sk->sk_lock.owned = 1;
3303 	spin_unlock_bh(&sk->sk_lock.slock);
3304 }
3305 EXPORT_SYMBOL(lock_sock_nested);
3306 
3307 void release_sock(struct sock *sk)
3308 {
3309 	spin_lock_bh(&sk->sk_lock.slock);
3310 	if (sk->sk_backlog.tail)
3311 		__release_sock(sk);
3312 
3313 	/* Warning : release_cb() might need to release sk ownership,
3314 	 * ie call sock_release_ownership(sk) before us.
3315 	 */
3316 	if (sk->sk_prot->release_cb)
3317 		sk->sk_prot->release_cb(sk);
3318 
3319 	sock_release_ownership(sk);
3320 	if (waitqueue_active(&sk->sk_lock.wq))
3321 		wake_up(&sk->sk_lock.wq);
3322 	spin_unlock_bh(&sk->sk_lock.slock);
3323 }
3324 EXPORT_SYMBOL(release_sock);
3325 
3326 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3327 {
3328 	might_sleep();
3329 	spin_lock_bh(&sk->sk_lock.slock);
3330 
3331 	if (!sock_owned_by_user_nocheck(sk)) {
3332 		/*
3333 		 * Fast path return with bottom halves disabled and
3334 		 * sock::sk_lock.slock held.
3335 		 *
3336 		 * The 'mutex' is not contended and holding
3337 		 * sock::sk_lock.slock prevents all other lockers to
3338 		 * proceed so the corresponding unlock_sock_fast() can
3339 		 * avoid the slow path of release_sock() completely and
3340 		 * just release slock.
3341 		 *
3342 		 * From a semantical POV this is equivalent to 'acquiring'
3343 		 * the 'mutex', hence the corresponding lockdep
3344 		 * mutex_release() has to happen in the fast path of
3345 		 * unlock_sock_fast().
3346 		 */
3347 		return false;
3348 	}
3349 
3350 	__lock_sock(sk);
3351 	sk->sk_lock.owned = 1;
3352 	__acquire(&sk->sk_lock.slock);
3353 	spin_unlock_bh(&sk->sk_lock.slock);
3354 	return true;
3355 }
3356 EXPORT_SYMBOL(__lock_sock_fast);
3357 
3358 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3359 		   bool timeval, bool time32)
3360 {
3361 	struct sock *sk = sock->sk;
3362 	struct timespec64 ts;
3363 
3364 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3365 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3366 	if (ts.tv_sec == -1)
3367 		return -ENOENT;
3368 	if (ts.tv_sec == 0) {
3369 		ktime_t kt = ktime_get_real();
3370 		sock_write_timestamp(sk, kt);
3371 		ts = ktime_to_timespec64(kt);
3372 	}
3373 
3374 	if (timeval)
3375 		ts.tv_nsec /= 1000;
3376 
3377 #ifdef CONFIG_COMPAT_32BIT_TIME
3378 	if (time32)
3379 		return put_old_timespec32(&ts, userstamp);
3380 #endif
3381 #ifdef CONFIG_SPARC64
3382 	/* beware of padding in sparc64 timeval */
3383 	if (timeval && !in_compat_syscall()) {
3384 		struct __kernel_old_timeval __user tv = {
3385 			.tv_sec = ts.tv_sec,
3386 			.tv_usec = ts.tv_nsec,
3387 		};
3388 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3389 			return -EFAULT;
3390 		return 0;
3391 	}
3392 #endif
3393 	return put_timespec64(&ts, userstamp);
3394 }
3395 EXPORT_SYMBOL(sock_gettstamp);
3396 
3397 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3398 {
3399 	if (!sock_flag(sk, flag)) {
3400 		unsigned long previous_flags = sk->sk_flags;
3401 
3402 		sock_set_flag(sk, flag);
3403 		/*
3404 		 * we just set one of the two flags which require net
3405 		 * time stamping, but time stamping might have been on
3406 		 * already because of the other one
3407 		 */
3408 		if (sock_needs_netstamp(sk) &&
3409 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3410 			net_enable_timestamp();
3411 	}
3412 }
3413 
3414 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3415 		       int level, int type)
3416 {
3417 	struct sock_exterr_skb *serr;
3418 	struct sk_buff *skb;
3419 	int copied, err;
3420 
3421 	err = -EAGAIN;
3422 	skb = sock_dequeue_err_skb(sk);
3423 	if (skb == NULL)
3424 		goto out;
3425 
3426 	copied = skb->len;
3427 	if (copied > len) {
3428 		msg->msg_flags |= MSG_TRUNC;
3429 		copied = len;
3430 	}
3431 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3432 	if (err)
3433 		goto out_free_skb;
3434 
3435 	sock_recv_timestamp(msg, sk, skb);
3436 
3437 	serr = SKB_EXT_ERR(skb);
3438 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3439 
3440 	msg->msg_flags |= MSG_ERRQUEUE;
3441 	err = copied;
3442 
3443 out_free_skb:
3444 	kfree_skb(skb);
3445 out:
3446 	return err;
3447 }
3448 EXPORT_SYMBOL(sock_recv_errqueue);
3449 
3450 /*
3451  *	Get a socket option on an socket.
3452  *
3453  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3454  *	asynchronous errors should be reported by getsockopt. We assume
3455  *	this means if you specify SO_ERROR (otherwise whats the point of it).
3456  */
3457 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3458 			   char __user *optval, int __user *optlen)
3459 {
3460 	struct sock *sk = sock->sk;
3461 
3462 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3463 }
3464 EXPORT_SYMBOL(sock_common_getsockopt);
3465 
3466 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3467 			int flags)
3468 {
3469 	struct sock *sk = sock->sk;
3470 	int addr_len = 0;
3471 	int err;
3472 
3473 	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
3474 				   flags & ~MSG_DONTWAIT, &addr_len);
3475 	if (err >= 0)
3476 		msg->msg_namelen = addr_len;
3477 	return err;
3478 }
3479 EXPORT_SYMBOL(sock_common_recvmsg);
3480 
3481 /*
3482  *	Set socket options on an inet socket.
3483  */
3484 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3485 			   sockptr_t optval, unsigned int optlen)
3486 {
3487 	struct sock *sk = sock->sk;
3488 
3489 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3490 }
3491 EXPORT_SYMBOL(sock_common_setsockopt);
3492 
3493 void sk_common_release(struct sock *sk)
3494 {
3495 	if (sk->sk_prot->destroy)
3496 		sk->sk_prot->destroy(sk);
3497 
3498 	/*
3499 	 * Observation: when sk_common_release is called, processes have
3500 	 * no access to socket. But net still has.
3501 	 * Step one, detach it from networking:
3502 	 *
3503 	 * A. Remove from hash tables.
3504 	 */
3505 
3506 	sk->sk_prot->unhash(sk);
3507 
3508 	/*
3509 	 * In this point socket cannot receive new packets, but it is possible
3510 	 * that some packets are in flight because some CPU runs receiver and
3511 	 * did hash table lookup before we unhashed socket. They will achieve
3512 	 * receive queue and will be purged by socket destructor.
3513 	 *
3514 	 * Also we still have packets pending on receive queue and probably,
3515 	 * our own packets waiting in device queues. sock_destroy will drain
3516 	 * receive queue, but transmitted packets will delay socket destruction
3517 	 * until the last reference will be released.
3518 	 */
3519 
3520 	sock_orphan(sk);
3521 
3522 	xfrm_sk_free_policy(sk);
3523 
3524 	sk_refcnt_debug_release(sk);
3525 
3526 	sock_put(sk);
3527 }
3528 EXPORT_SYMBOL(sk_common_release);
3529 
3530 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3531 {
3532 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3533 
3534 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3535 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3536 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3537 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3538 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3539 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3540 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3541 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3542 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3543 }
3544 
3545 #ifdef CONFIG_PROC_FS
3546 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3547 
3548 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3549 {
3550 	int cpu, idx = prot->inuse_idx;
3551 	int res = 0;
3552 
3553 	for_each_possible_cpu(cpu)
3554 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3555 
3556 	return res >= 0 ? res : 0;
3557 }
3558 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3559 
3560 int sock_inuse_get(struct net *net)
3561 {
3562 	int cpu, res = 0;
3563 
3564 	for_each_possible_cpu(cpu)
3565 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3566 
3567 	return res;
3568 }
3569 
3570 EXPORT_SYMBOL_GPL(sock_inuse_get);
3571 
3572 static int __net_init sock_inuse_init_net(struct net *net)
3573 {
3574 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3575 	if (net->core.prot_inuse == NULL)
3576 		return -ENOMEM;
3577 	return 0;
3578 }
3579 
3580 static void __net_exit sock_inuse_exit_net(struct net *net)
3581 {
3582 	free_percpu(net->core.prot_inuse);
3583 }
3584 
3585 static struct pernet_operations net_inuse_ops = {
3586 	.init = sock_inuse_init_net,
3587 	.exit = sock_inuse_exit_net,
3588 };
3589 
3590 static __init int net_inuse_init(void)
3591 {
3592 	if (register_pernet_subsys(&net_inuse_ops))
3593 		panic("Cannot initialize net inuse counters");
3594 
3595 	return 0;
3596 }
3597 
3598 core_initcall(net_inuse_init);
3599 
3600 static int assign_proto_idx(struct proto *prot)
3601 {
3602 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3603 
3604 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3605 		pr_err("PROTO_INUSE_NR exhausted\n");
3606 		return -ENOSPC;
3607 	}
3608 
3609 	set_bit(prot->inuse_idx, proto_inuse_idx);
3610 	return 0;
3611 }
3612 
3613 static void release_proto_idx(struct proto *prot)
3614 {
3615 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3616 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3617 }
3618 #else
3619 static inline int assign_proto_idx(struct proto *prot)
3620 {
3621 	return 0;
3622 }
3623 
3624 static inline void release_proto_idx(struct proto *prot)
3625 {
3626 }
3627 
3628 #endif
3629 
3630 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3631 {
3632 	if (!twsk_prot)
3633 		return;
3634 	kfree(twsk_prot->twsk_slab_name);
3635 	twsk_prot->twsk_slab_name = NULL;
3636 	kmem_cache_destroy(twsk_prot->twsk_slab);
3637 	twsk_prot->twsk_slab = NULL;
3638 }
3639 
3640 static int tw_prot_init(const struct proto *prot)
3641 {
3642 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3643 
3644 	if (!twsk_prot)
3645 		return 0;
3646 
3647 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3648 					      prot->name);
3649 	if (!twsk_prot->twsk_slab_name)
3650 		return -ENOMEM;
3651 
3652 	twsk_prot->twsk_slab =
3653 		kmem_cache_create(twsk_prot->twsk_slab_name,
3654 				  twsk_prot->twsk_obj_size, 0,
3655 				  SLAB_ACCOUNT | prot->slab_flags,
3656 				  NULL);
3657 	if (!twsk_prot->twsk_slab) {
3658 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3659 			prot->name);
3660 		return -ENOMEM;
3661 	}
3662 
3663 	return 0;
3664 }
3665 
3666 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3667 {
3668 	if (!rsk_prot)
3669 		return;
3670 	kfree(rsk_prot->slab_name);
3671 	rsk_prot->slab_name = NULL;
3672 	kmem_cache_destroy(rsk_prot->slab);
3673 	rsk_prot->slab = NULL;
3674 }
3675 
3676 static int req_prot_init(const struct proto *prot)
3677 {
3678 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3679 
3680 	if (!rsk_prot)
3681 		return 0;
3682 
3683 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3684 					prot->name);
3685 	if (!rsk_prot->slab_name)
3686 		return -ENOMEM;
3687 
3688 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3689 					   rsk_prot->obj_size, 0,
3690 					   SLAB_ACCOUNT | prot->slab_flags,
3691 					   NULL);
3692 
3693 	if (!rsk_prot->slab) {
3694 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3695 			prot->name);
3696 		return -ENOMEM;
3697 	}
3698 	return 0;
3699 }
3700 
3701 int proto_register(struct proto *prot, int alloc_slab)
3702 {
3703 	int ret = -ENOBUFS;
3704 
3705 	if (alloc_slab) {
3706 		prot->slab = kmem_cache_create_usercopy(prot->name,
3707 					prot->obj_size, 0,
3708 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3709 					prot->slab_flags,
3710 					prot->useroffset, prot->usersize,
3711 					NULL);
3712 
3713 		if (prot->slab == NULL) {
3714 			pr_crit("%s: Can't create sock SLAB cache!\n",
3715 				prot->name);
3716 			goto out;
3717 		}
3718 
3719 		if (req_prot_init(prot))
3720 			goto out_free_request_sock_slab;
3721 
3722 		if (tw_prot_init(prot))
3723 			goto out_free_timewait_sock_slab;
3724 	}
3725 
3726 	mutex_lock(&proto_list_mutex);
3727 	ret = assign_proto_idx(prot);
3728 	if (ret) {
3729 		mutex_unlock(&proto_list_mutex);
3730 		goto out_free_timewait_sock_slab;
3731 	}
3732 	list_add(&prot->node, &proto_list);
3733 	mutex_unlock(&proto_list_mutex);
3734 	return ret;
3735 
3736 out_free_timewait_sock_slab:
3737 	if (alloc_slab)
3738 		tw_prot_cleanup(prot->twsk_prot);
3739 out_free_request_sock_slab:
3740 	if (alloc_slab) {
3741 		req_prot_cleanup(prot->rsk_prot);
3742 
3743 		kmem_cache_destroy(prot->slab);
3744 		prot->slab = NULL;
3745 	}
3746 out:
3747 	return ret;
3748 }
3749 EXPORT_SYMBOL(proto_register);
3750 
3751 void proto_unregister(struct proto *prot)
3752 {
3753 	mutex_lock(&proto_list_mutex);
3754 	release_proto_idx(prot);
3755 	list_del(&prot->node);
3756 	mutex_unlock(&proto_list_mutex);
3757 
3758 	kmem_cache_destroy(prot->slab);
3759 	prot->slab = NULL;
3760 
3761 	req_prot_cleanup(prot->rsk_prot);
3762 	tw_prot_cleanup(prot->twsk_prot);
3763 }
3764 EXPORT_SYMBOL(proto_unregister);
3765 
3766 int sock_load_diag_module(int family, int protocol)
3767 {
3768 	if (!protocol) {
3769 		if (!sock_is_registered(family))
3770 			return -ENOENT;
3771 
3772 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3773 				      NETLINK_SOCK_DIAG, family);
3774 	}
3775 
3776 #ifdef CONFIG_INET
3777 	if (family == AF_INET &&
3778 	    protocol != IPPROTO_RAW &&
3779 	    protocol < MAX_INET_PROTOS &&
3780 	    !rcu_access_pointer(inet_protos[protocol]))
3781 		return -ENOENT;
3782 #endif
3783 
3784 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3785 			      NETLINK_SOCK_DIAG, family, protocol);
3786 }
3787 EXPORT_SYMBOL(sock_load_diag_module);
3788 
3789 #ifdef CONFIG_PROC_FS
3790 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3791 	__acquires(proto_list_mutex)
3792 {
3793 	mutex_lock(&proto_list_mutex);
3794 	return seq_list_start_head(&proto_list, *pos);
3795 }
3796 
3797 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3798 {
3799 	return seq_list_next(v, &proto_list, pos);
3800 }
3801 
3802 static void proto_seq_stop(struct seq_file *seq, void *v)
3803 	__releases(proto_list_mutex)
3804 {
3805 	mutex_unlock(&proto_list_mutex);
3806 }
3807 
3808 static char proto_method_implemented(const void *method)
3809 {
3810 	return method == NULL ? 'n' : 'y';
3811 }
3812 static long sock_prot_memory_allocated(struct proto *proto)
3813 {
3814 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3815 }
3816 
3817 static const char *sock_prot_memory_pressure(struct proto *proto)
3818 {
3819 	return proto->memory_pressure != NULL ?
3820 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3821 }
3822 
3823 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3824 {
3825 
3826 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
3827 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3828 		   proto->name,
3829 		   proto->obj_size,
3830 		   sock_prot_inuse_get(seq_file_net(seq), proto),
3831 		   sock_prot_memory_allocated(proto),
3832 		   sock_prot_memory_pressure(proto),
3833 		   proto->max_header,
3834 		   proto->slab == NULL ? "no" : "yes",
3835 		   module_name(proto->owner),
3836 		   proto_method_implemented(proto->close),
3837 		   proto_method_implemented(proto->connect),
3838 		   proto_method_implemented(proto->disconnect),
3839 		   proto_method_implemented(proto->accept),
3840 		   proto_method_implemented(proto->ioctl),
3841 		   proto_method_implemented(proto->init),
3842 		   proto_method_implemented(proto->destroy),
3843 		   proto_method_implemented(proto->shutdown),
3844 		   proto_method_implemented(proto->setsockopt),
3845 		   proto_method_implemented(proto->getsockopt),
3846 		   proto_method_implemented(proto->sendmsg),
3847 		   proto_method_implemented(proto->recvmsg),
3848 		   proto_method_implemented(proto->sendpage),
3849 		   proto_method_implemented(proto->bind),
3850 		   proto_method_implemented(proto->backlog_rcv),
3851 		   proto_method_implemented(proto->hash),
3852 		   proto_method_implemented(proto->unhash),
3853 		   proto_method_implemented(proto->get_port),
3854 		   proto_method_implemented(proto->enter_memory_pressure));
3855 }
3856 
3857 static int proto_seq_show(struct seq_file *seq, void *v)
3858 {
3859 	if (v == &proto_list)
3860 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3861 			   "protocol",
3862 			   "size",
3863 			   "sockets",
3864 			   "memory",
3865 			   "press",
3866 			   "maxhdr",
3867 			   "slab",
3868 			   "module",
3869 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3870 	else
3871 		proto_seq_printf(seq, list_entry(v, struct proto, node));
3872 	return 0;
3873 }
3874 
3875 static const struct seq_operations proto_seq_ops = {
3876 	.start  = proto_seq_start,
3877 	.next   = proto_seq_next,
3878 	.stop   = proto_seq_stop,
3879 	.show   = proto_seq_show,
3880 };
3881 
3882 static __net_init int proto_init_net(struct net *net)
3883 {
3884 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
3885 			sizeof(struct seq_net_private)))
3886 		return -ENOMEM;
3887 
3888 	return 0;
3889 }
3890 
3891 static __net_exit void proto_exit_net(struct net *net)
3892 {
3893 	remove_proc_entry("protocols", net->proc_net);
3894 }
3895 
3896 
3897 static __net_initdata struct pernet_operations proto_net_ops = {
3898 	.init = proto_init_net,
3899 	.exit = proto_exit_net,
3900 };
3901 
3902 static int __init proto_init(void)
3903 {
3904 	return register_pernet_subsys(&proto_net_ops);
3905 }
3906 
3907 subsys_initcall(proto_init);
3908 
3909 #endif /* PROC_FS */
3910 
3911 #ifdef CONFIG_NET_RX_BUSY_POLL
3912 bool sk_busy_loop_end(void *p, unsigned long start_time)
3913 {
3914 	struct sock *sk = p;
3915 
3916 	return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
3917 	       sk_busy_loop_timeout(sk, start_time);
3918 }
3919 EXPORT_SYMBOL(sk_busy_loop_end);
3920 #endif /* CONFIG_NET_RX_BUSY_POLL */
3921 
3922 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
3923 {
3924 	if (!sk->sk_prot->bind_add)
3925 		return -EOPNOTSUPP;
3926 	return sk->sk_prot->bind_add(sk, addr, addr_len);
3927 }
3928 EXPORT_SYMBOL(sock_bind_add);
3929