xref: /linux/net/core/sock.c (revision bbcf0f55e57841e532ab395596db9197e8d53e8d)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * INET		An implementation of the TCP/IP protocol suite for the LINUX
4  *		operating system.  INET is implemented using the  BSD Socket
5  *		interface as the means of communication with the user level.
6  *
7  *		Generic socket support routines. Memory allocators, socket lock/release
8  *		handler for protocols to use and generic option handler.
9  *
10  * Authors:	Ross Biro
11  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12  *		Florian La Roche, <flla@stud.uni-sb.de>
13  *		Alan Cox, <A.Cox@swansea.ac.uk>
14  *
15  * Fixes:
16  *		Alan Cox	: 	Numerous verify_area() problems
17  *		Alan Cox	:	Connecting on a connecting socket
18  *					now returns an error for tcp.
19  *		Alan Cox	:	sock->protocol is set correctly.
20  *					and is not sometimes left as 0.
21  *		Alan Cox	:	connect handles icmp errors on a
22  *					connect properly. Unfortunately there
23  *					is a restart syscall nasty there. I
24  *					can't match BSD without hacking the C
25  *					library. Ideas urgently sought!
26  *		Alan Cox	:	Disallow bind() to addresses that are
27  *					not ours - especially broadcast ones!!
28  *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
29  *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
30  *					instead they leave that for the DESTROY timer.
31  *		Alan Cox	:	Clean up error flag in accept
32  *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
33  *					was buggy. Put a remove_sock() in the handler
34  *					for memory when we hit 0. Also altered the timer
35  *					code. The ACK stuff can wait and needs major
36  *					TCP layer surgery.
37  *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
38  *					and fixed timer/inet_bh race.
39  *		Alan Cox	:	Added zapped flag for TCP
40  *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
41  *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42  *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
43  *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
44  *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45  *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
46  *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
47  *	Pauline Middelink	:	identd support
48  *		Alan Cox	:	Fixed connect() taking signals I think.
49  *		Alan Cox	:	SO_LINGER supported
50  *		Alan Cox	:	Error reporting fixes
51  *		Anonymous	:	inet_create tidied up (sk->reuse setting)
52  *		Alan Cox	:	inet sockets don't set sk->type!
53  *		Alan Cox	:	Split socket option code
54  *		Alan Cox	:	Callbacks
55  *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
56  *		Alex		:	Removed restriction on inet fioctl
57  *		Alan Cox	:	Splitting INET from NET core
58  *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
59  *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
60  *		Alan Cox	:	Split IP from generic code
61  *		Alan Cox	:	New kfree_skbmem()
62  *		Alan Cox	:	Make SO_DEBUG superuser only.
63  *		Alan Cox	:	Allow anyone to clear SO_DEBUG
64  *					(compatibility fix)
65  *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
66  *		Alan Cox	:	Allocator for a socket is settable.
67  *		Alan Cox	:	SO_ERROR includes soft errors.
68  *		Alan Cox	:	Allow NULL arguments on some SO_ opts
69  *		Alan Cox	: 	Generic socket allocation to make hooks
70  *					easier (suggested by Craig Metz).
71  *		Michael Pall	:	SO_ERROR returns positive errno again
72  *              Steve Whitehouse:       Added default destructor to free
73  *                                      protocol private data.
74  *              Steve Whitehouse:       Added various other default routines
75  *                                      common to several socket families.
76  *              Chris Evans     :       Call suser() check last on F_SETOWN
77  *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78  *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
79  *		Andi Kleen	:	Fix write_space callback
80  *		Chris Evans	:	Security fixes - signedness again
81  *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
82  *
83  * To Fix:
84  */
85 
86 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
87 
88 #include <asm/unaligned.h>
89 #include <linux/capability.h>
90 #include <linux/errno.h>
91 #include <linux/errqueue.h>
92 #include <linux/types.h>
93 #include <linux/socket.h>
94 #include <linux/in.h>
95 #include <linux/kernel.h>
96 #include <linux/module.h>
97 #include <linux/proc_fs.h>
98 #include <linux/seq_file.h>
99 #include <linux/sched.h>
100 #include <linux/sched/mm.h>
101 #include <linux/timer.h>
102 #include <linux/string.h>
103 #include <linux/sockios.h>
104 #include <linux/net.h>
105 #include <linux/mm.h>
106 #include <linux/slab.h>
107 #include <linux/interrupt.h>
108 #include <linux/poll.h>
109 #include <linux/tcp.h>
110 #include <linux/init.h>
111 #include <linux/highmem.h>
112 #include <linux/user_namespace.h>
113 #include <linux/static_key.h>
114 #include <linux/memcontrol.h>
115 #include <linux/prefetch.h>
116 #include <linux/compat.h>
117 
118 #include <linux/uaccess.h>
119 
120 #include <linux/netdevice.h>
121 #include <net/protocol.h>
122 #include <linux/skbuff.h>
123 #include <net/net_namespace.h>
124 #include <net/request_sock.h>
125 #include <net/sock.h>
126 #include <linux/net_tstamp.h>
127 #include <net/xfrm.h>
128 #include <linux/ipsec.h>
129 #include <net/cls_cgroup.h>
130 #include <net/netprio_cgroup.h>
131 #include <linux/sock_diag.h>
132 
133 #include <linux/filter.h>
134 #include <net/sock_reuseport.h>
135 #include <net/bpf_sk_storage.h>
136 
137 #include <trace/events/sock.h>
138 
139 #include <net/tcp.h>
140 #include <net/busy_poll.h>
141 
142 #include <linux/ethtool.h>
143 
144 #include "dev.h"
145 
146 static DEFINE_MUTEX(proto_list_mutex);
147 static LIST_HEAD(proto_list);
148 
149 static void sock_def_write_space_wfree(struct sock *sk);
150 static void sock_def_write_space(struct sock *sk);
151 
152 /**
153  * sk_ns_capable - General socket capability test
154  * @sk: Socket to use a capability on or through
155  * @user_ns: The user namespace of the capability to use
156  * @cap: The capability to use
157  *
158  * Test to see if the opener of the socket had when the socket was
159  * created and the current process has the capability @cap in the user
160  * namespace @user_ns.
161  */
162 bool sk_ns_capable(const struct sock *sk,
163 		   struct user_namespace *user_ns, int cap)
164 {
165 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
166 		ns_capable(user_ns, cap);
167 }
168 EXPORT_SYMBOL(sk_ns_capable);
169 
170 /**
171  * sk_capable - Socket global capability test
172  * @sk: Socket to use a capability on or through
173  * @cap: The global capability to use
174  *
175  * Test to see if the opener of the socket had when the socket was
176  * created and the current process has the capability @cap in all user
177  * namespaces.
178  */
179 bool sk_capable(const struct sock *sk, int cap)
180 {
181 	return sk_ns_capable(sk, &init_user_ns, cap);
182 }
183 EXPORT_SYMBOL(sk_capable);
184 
185 /**
186  * sk_net_capable - Network namespace socket capability test
187  * @sk: Socket to use a capability on or through
188  * @cap: The capability to use
189  *
190  * Test to see if the opener of the socket had when the socket was created
191  * and the current process has the capability @cap over the network namespace
192  * the socket is a member of.
193  */
194 bool sk_net_capable(const struct sock *sk, int cap)
195 {
196 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
197 }
198 EXPORT_SYMBOL(sk_net_capable);
199 
200 /*
201  * Each address family might have different locking rules, so we have
202  * one slock key per address family and separate keys for internal and
203  * userspace sockets.
204  */
205 static struct lock_class_key af_family_keys[AF_MAX];
206 static struct lock_class_key af_family_kern_keys[AF_MAX];
207 static struct lock_class_key af_family_slock_keys[AF_MAX];
208 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
209 
210 /*
211  * Make lock validator output more readable. (we pre-construct these
212  * strings build-time, so that runtime initialization of socket
213  * locks is fast):
214  */
215 
216 #define _sock_locks(x)						  \
217   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
218   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
219   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
220   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
221   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
222   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
223   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
224   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
225   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
226   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
227   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
228   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
229   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
230   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
231   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
232   x "AF_MCTP"  , \
233   x "AF_MAX"
234 
235 static const char *const af_family_key_strings[AF_MAX+1] = {
236 	_sock_locks("sk_lock-")
237 };
238 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
239 	_sock_locks("slock-")
240 };
241 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
242 	_sock_locks("clock-")
243 };
244 
245 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
246 	_sock_locks("k-sk_lock-")
247 };
248 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
249 	_sock_locks("k-slock-")
250 };
251 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
252 	_sock_locks("k-clock-")
253 };
254 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
255 	_sock_locks("rlock-")
256 };
257 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
258 	_sock_locks("wlock-")
259 };
260 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
261 	_sock_locks("elock-")
262 };
263 
264 /*
265  * sk_callback_lock and sk queues locking rules are per-address-family,
266  * so split the lock classes by using a per-AF key:
267  */
268 static struct lock_class_key af_callback_keys[AF_MAX];
269 static struct lock_class_key af_rlock_keys[AF_MAX];
270 static struct lock_class_key af_wlock_keys[AF_MAX];
271 static struct lock_class_key af_elock_keys[AF_MAX];
272 static struct lock_class_key af_kern_callback_keys[AF_MAX];
273 
274 /* Run time adjustable parameters. */
275 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
276 EXPORT_SYMBOL(sysctl_wmem_max);
277 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
278 EXPORT_SYMBOL(sysctl_rmem_max);
279 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
280 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
281 
282 /* Maximal space eaten by iovec or ancillary data plus some space */
283 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
284 EXPORT_SYMBOL(sysctl_optmem_max);
285 
286 int sysctl_tstamp_allow_data __read_mostly = 1;
287 
288 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
289 EXPORT_SYMBOL_GPL(memalloc_socks_key);
290 
291 /**
292  * sk_set_memalloc - sets %SOCK_MEMALLOC
293  * @sk: socket to set it on
294  *
295  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
296  * It's the responsibility of the admin to adjust min_free_kbytes
297  * to meet the requirements
298  */
299 void sk_set_memalloc(struct sock *sk)
300 {
301 	sock_set_flag(sk, SOCK_MEMALLOC);
302 	sk->sk_allocation |= __GFP_MEMALLOC;
303 	static_branch_inc(&memalloc_socks_key);
304 }
305 EXPORT_SYMBOL_GPL(sk_set_memalloc);
306 
307 void sk_clear_memalloc(struct sock *sk)
308 {
309 	sock_reset_flag(sk, SOCK_MEMALLOC);
310 	sk->sk_allocation &= ~__GFP_MEMALLOC;
311 	static_branch_dec(&memalloc_socks_key);
312 
313 	/*
314 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
315 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
316 	 * it has rmem allocations due to the last swapfile being deactivated
317 	 * but there is a risk that the socket is unusable due to exceeding
318 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
319 	 */
320 	sk_mem_reclaim(sk);
321 }
322 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
323 
324 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
325 {
326 	int ret;
327 	unsigned int noreclaim_flag;
328 
329 	/* these should have been dropped before queueing */
330 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
331 
332 	noreclaim_flag = memalloc_noreclaim_save();
333 	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
334 				 tcp_v6_do_rcv,
335 				 tcp_v4_do_rcv,
336 				 sk, skb);
337 	memalloc_noreclaim_restore(noreclaim_flag);
338 
339 	return ret;
340 }
341 EXPORT_SYMBOL(__sk_backlog_rcv);
342 
343 void sk_error_report(struct sock *sk)
344 {
345 	sk->sk_error_report(sk);
346 
347 	switch (sk->sk_family) {
348 	case AF_INET:
349 		fallthrough;
350 	case AF_INET6:
351 		trace_inet_sk_error_report(sk);
352 		break;
353 	default:
354 		break;
355 	}
356 }
357 EXPORT_SYMBOL(sk_error_report);
358 
359 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
360 {
361 	struct __kernel_sock_timeval tv;
362 
363 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
364 		tv.tv_sec = 0;
365 		tv.tv_usec = 0;
366 	} else {
367 		tv.tv_sec = timeo / HZ;
368 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
369 	}
370 
371 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
372 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
373 		*(struct old_timeval32 *)optval = tv32;
374 		return sizeof(tv32);
375 	}
376 
377 	if (old_timeval) {
378 		struct __kernel_old_timeval old_tv;
379 		old_tv.tv_sec = tv.tv_sec;
380 		old_tv.tv_usec = tv.tv_usec;
381 		*(struct __kernel_old_timeval *)optval = old_tv;
382 		return sizeof(old_tv);
383 	}
384 
385 	*(struct __kernel_sock_timeval *)optval = tv;
386 	return sizeof(tv);
387 }
388 EXPORT_SYMBOL(sock_get_timeout);
389 
390 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
391 			   sockptr_t optval, int optlen, bool old_timeval)
392 {
393 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
394 		struct old_timeval32 tv32;
395 
396 		if (optlen < sizeof(tv32))
397 			return -EINVAL;
398 
399 		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
400 			return -EFAULT;
401 		tv->tv_sec = tv32.tv_sec;
402 		tv->tv_usec = tv32.tv_usec;
403 	} else if (old_timeval) {
404 		struct __kernel_old_timeval old_tv;
405 
406 		if (optlen < sizeof(old_tv))
407 			return -EINVAL;
408 		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
409 			return -EFAULT;
410 		tv->tv_sec = old_tv.tv_sec;
411 		tv->tv_usec = old_tv.tv_usec;
412 	} else {
413 		if (optlen < sizeof(*tv))
414 			return -EINVAL;
415 		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
416 			return -EFAULT;
417 	}
418 
419 	return 0;
420 }
421 EXPORT_SYMBOL(sock_copy_user_timeval);
422 
423 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
424 			    bool old_timeval)
425 {
426 	struct __kernel_sock_timeval tv;
427 	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
428 
429 	if (err)
430 		return err;
431 
432 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
433 		return -EDOM;
434 
435 	if (tv.tv_sec < 0) {
436 		static int warned __read_mostly;
437 
438 		*timeo_p = 0;
439 		if (warned < 10 && net_ratelimit()) {
440 			warned++;
441 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
442 				__func__, current->comm, task_pid_nr(current));
443 		}
444 		return 0;
445 	}
446 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
447 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
448 		return 0;
449 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
450 		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
451 	return 0;
452 }
453 
454 static bool sock_needs_netstamp(const struct sock *sk)
455 {
456 	switch (sk->sk_family) {
457 	case AF_UNSPEC:
458 	case AF_UNIX:
459 		return false;
460 	default:
461 		return true;
462 	}
463 }
464 
465 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
466 {
467 	if (sk->sk_flags & flags) {
468 		sk->sk_flags &= ~flags;
469 		if (sock_needs_netstamp(sk) &&
470 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
471 			net_disable_timestamp();
472 	}
473 }
474 
475 
476 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
477 {
478 	unsigned long flags;
479 	struct sk_buff_head *list = &sk->sk_receive_queue;
480 
481 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
482 		atomic_inc(&sk->sk_drops);
483 		trace_sock_rcvqueue_full(sk, skb);
484 		return -ENOMEM;
485 	}
486 
487 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
488 		atomic_inc(&sk->sk_drops);
489 		return -ENOBUFS;
490 	}
491 
492 	skb->dev = NULL;
493 	skb_set_owner_r(skb, sk);
494 
495 	/* we escape from rcu protected region, make sure we dont leak
496 	 * a norefcounted dst
497 	 */
498 	skb_dst_force(skb);
499 
500 	spin_lock_irqsave(&list->lock, flags);
501 	sock_skb_set_dropcount(sk, skb);
502 	__skb_queue_tail(list, skb);
503 	spin_unlock_irqrestore(&list->lock, flags);
504 
505 	if (!sock_flag(sk, SOCK_DEAD))
506 		sk->sk_data_ready(sk);
507 	return 0;
508 }
509 EXPORT_SYMBOL(__sock_queue_rcv_skb);
510 
511 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
512 			      enum skb_drop_reason *reason)
513 {
514 	enum skb_drop_reason drop_reason;
515 	int err;
516 
517 	err = sk_filter(sk, skb);
518 	if (err) {
519 		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
520 		goto out;
521 	}
522 	err = __sock_queue_rcv_skb(sk, skb);
523 	switch (err) {
524 	case -ENOMEM:
525 		drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
526 		break;
527 	case -ENOBUFS:
528 		drop_reason = SKB_DROP_REASON_PROTO_MEM;
529 		break;
530 	default:
531 		drop_reason = SKB_NOT_DROPPED_YET;
532 		break;
533 	}
534 out:
535 	if (reason)
536 		*reason = drop_reason;
537 	return err;
538 }
539 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
540 
541 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
542 		     const int nested, unsigned int trim_cap, bool refcounted)
543 {
544 	int rc = NET_RX_SUCCESS;
545 
546 	if (sk_filter_trim_cap(sk, skb, trim_cap))
547 		goto discard_and_relse;
548 
549 	skb->dev = NULL;
550 
551 	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
552 		atomic_inc(&sk->sk_drops);
553 		goto discard_and_relse;
554 	}
555 	if (nested)
556 		bh_lock_sock_nested(sk);
557 	else
558 		bh_lock_sock(sk);
559 	if (!sock_owned_by_user(sk)) {
560 		/*
561 		 * trylock + unlock semantics:
562 		 */
563 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
564 
565 		rc = sk_backlog_rcv(sk, skb);
566 
567 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
568 	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
569 		bh_unlock_sock(sk);
570 		atomic_inc(&sk->sk_drops);
571 		goto discard_and_relse;
572 	}
573 
574 	bh_unlock_sock(sk);
575 out:
576 	if (refcounted)
577 		sock_put(sk);
578 	return rc;
579 discard_and_relse:
580 	kfree_skb(skb);
581 	goto out;
582 }
583 EXPORT_SYMBOL(__sk_receive_skb);
584 
585 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
586 							  u32));
587 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
588 							   u32));
589 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
590 {
591 	struct dst_entry *dst = __sk_dst_get(sk);
592 
593 	if (dst && dst->obsolete &&
594 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
595 			       dst, cookie) == NULL) {
596 		sk_tx_queue_clear(sk);
597 		sk->sk_dst_pending_confirm = 0;
598 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
599 		dst_release(dst);
600 		return NULL;
601 	}
602 
603 	return dst;
604 }
605 EXPORT_SYMBOL(__sk_dst_check);
606 
607 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
608 {
609 	struct dst_entry *dst = sk_dst_get(sk);
610 
611 	if (dst && dst->obsolete &&
612 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
613 			       dst, cookie) == NULL) {
614 		sk_dst_reset(sk);
615 		dst_release(dst);
616 		return NULL;
617 	}
618 
619 	return dst;
620 }
621 EXPORT_SYMBOL(sk_dst_check);
622 
623 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
624 {
625 	int ret = -ENOPROTOOPT;
626 #ifdef CONFIG_NETDEVICES
627 	struct net *net = sock_net(sk);
628 
629 	/* Sorry... */
630 	ret = -EPERM;
631 	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
632 		goto out;
633 
634 	ret = -EINVAL;
635 	if (ifindex < 0)
636 		goto out;
637 
638 	/* Paired with all READ_ONCE() done locklessly. */
639 	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
640 
641 	if (sk->sk_prot->rehash)
642 		sk->sk_prot->rehash(sk);
643 	sk_dst_reset(sk);
644 
645 	ret = 0;
646 
647 out:
648 #endif
649 
650 	return ret;
651 }
652 
653 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
654 {
655 	int ret;
656 
657 	if (lock_sk)
658 		lock_sock(sk);
659 	ret = sock_bindtoindex_locked(sk, ifindex);
660 	if (lock_sk)
661 		release_sock(sk);
662 
663 	return ret;
664 }
665 EXPORT_SYMBOL(sock_bindtoindex);
666 
667 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
668 {
669 	int ret = -ENOPROTOOPT;
670 #ifdef CONFIG_NETDEVICES
671 	struct net *net = sock_net(sk);
672 	char devname[IFNAMSIZ];
673 	int index;
674 
675 	ret = -EINVAL;
676 	if (optlen < 0)
677 		goto out;
678 
679 	/* Bind this socket to a particular device like "eth0",
680 	 * as specified in the passed interface name. If the
681 	 * name is "" or the option length is zero the socket
682 	 * is not bound.
683 	 */
684 	if (optlen > IFNAMSIZ - 1)
685 		optlen = IFNAMSIZ - 1;
686 	memset(devname, 0, sizeof(devname));
687 
688 	ret = -EFAULT;
689 	if (copy_from_sockptr(devname, optval, optlen))
690 		goto out;
691 
692 	index = 0;
693 	if (devname[0] != '\0') {
694 		struct net_device *dev;
695 
696 		rcu_read_lock();
697 		dev = dev_get_by_name_rcu(net, devname);
698 		if (dev)
699 			index = dev->ifindex;
700 		rcu_read_unlock();
701 		ret = -ENODEV;
702 		if (!dev)
703 			goto out;
704 	}
705 
706 	sockopt_lock_sock(sk);
707 	ret = sock_bindtoindex_locked(sk, index);
708 	sockopt_release_sock(sk);
709 out:
710 #endif
711 
712 	return ret;
713 }
714 
715 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
716 				int __user *optlen, int len)
717 {
718 	int ret = -ENOPROTOOPT;
719 #ifdef CONFIG_NETDEVICES
720 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
721 	struct net *net = sock_net(sk);
722 	char devname[IFNAMSIZ];
723 
724 	if (bound_dev_if == 0) {
725 		len = 0;
726 		goto zero;
727 	}
728 
729 	ret = -EINVAL;
730 	if (len < IFNAMSIZ)
731 		goto out;
732 
733 	ret = netdev_get_name(net, devname, bound_dev_if);
734 	if (ret)
735 		goto out;
736 
737 	len = strlen(devname) + 1;
738 
739 	ret = -EFAULT;
740 	if (copy_to_user(optval, devname, len))
741 		goto out;
742 
743 zero:
744 	ret = -EFAULT;
745 	if (put_user(len, optlen))
746 		goto out;
747 
748 	ret = 0;
749 
750 out:
751 #endif
752 
753 	return ret;
754 }
755 
756 bool sk_mc_loop(struct sock *sk)
757 {
758 	if (dev_recursion_level())
759 		return false;
760 	if (!sk)
761 		return true;
762 	switch (sk->sk_family) {
763 	case AF_INET:
764 		return inet_sk(sk)->mc_loop;
765 #if IS_ENABLED(CONFIG_IPV6)
766 	case AF_INET6:
767 		return inet6_sk(sk)->mc_loop;
768 #endif
769 	}
770 	WARN_ON_ONCE(1);
771 	return true;
772 }
773 EXPORT_SYMBOL(sk_mc_loop);
774 
775 void sock_set_reuseaddr(struct sock *sk)
776 {
777 	lock_sock(sk);
778 	sk->sk_reuse = SK_CAN_REUSE;
779 	release_sock(sk);
780 }
781 EXPORT_SYMBOL(sock_set_reuseaddr);
782 
783 void sock_set_reuseport(struct sock *sk)
784 {
785 	lock_sock(sk);
786 	sk->sk_reuseport = true;
787 	release_sock(sk);
788 }
789 EXPORT_SYMBOL(sock_set_reuseport);
790 
791 void sock_no_linger(struct sock *sk)
792 {
793 	lock_sock(sk);
794 	sk->sk_lingertime = 0;
795 	sock_set_flag(sk, SOCK_LINGER);
796 	release_sock(sk);
797 }
798 EXPORT_SYMBOL(sock_no_linger);
799 
800 void sock_set_priority(struct sock *sk, u32 priority)
801 {
802 	lock_sock(sk);
803 	sk->sk_priority = priority;
804 	release_sock(sk);
805 }
806 EXPORT_SYMBOL(sock_set_priority);
807 
808 void sock_set_sndtimeo(struct sock *sk, s64 secs)
809 {
810 	lock_sock(sk);
811 	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
812 		sk->sk_sndtimeo = secs * HZ;
813 	else
814 		sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
815 	release_sock(sk);
816 }
817 EXPORT_SYMBOL(sock_set_sndtimeo);
818 
819 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
820 {
821 	if (val)  {
822 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
823 		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
824 		sock_set_flag(sk, SOCK_RCVTSTAMP);
825 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
826 	} else {
827 		sock_reset_flag(sk, SOCK_RCVTSTAMP);
828 		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
829 	}
830 }
831 
832 void sock_enable_timestamps(struct sock *sk)
833 {
834 	lock_sock(sk);
835 	__sock_set_timestamps(sk, true, false, true);
836 	release_sock(sk);
837 }
838 EXPORT_SYMBOL(sock_enable_timestamps);
839 
840 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
841 {
842 	switch (optname) {
843 	case SO_TIMESTAMP_OLD:
844 		__sock_set_timestamps(sk, valbool, false, false);
845 		break;
846 	case SO_TIMESTAMP_NEW:
847 		__sock_set_timestamps(sk, valbool, true, false);
848 		break;
849 	case SO_TIMESTAMPNS_OLD:
850 		__sock_set_timestamps(sk, valbool, false, true);
851 		break;
852 	case SO_TIMESTAMPNS_NEW:
853 		__sock_set_timestamps(sk, valbool, true, true);
854 		break;
855 	}
856 }
857 
858 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
859 {
860 	struct net *net = sock_net(sk);
861 	struct net_device *dev = NULL;
862 	bool match = false;
863 	int *vclock_index;
864 	int i, num;
865 
866 	if (sk->sk_bound_dev_if)
867 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
868 
869 	if (!dev) {
870 		pr_err("%s: sock not bind to device\n", __func__);
871 		return -EOPNOTSUPP;
872 	}
873 
874 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
875 	dev_put(dev);
876 
877 	for (i = 0; i < num; i++) {
878 		if (*(vclock_index + i) == phc_index) {
879 			match = true;
880 			break;
881 		}
882 	}
883 
884 	if (num > 0)
885 		kfree(vclock_index);
886 
887 	if (!match)
888 		return -EINVAL;
889 
890 	sk->sk_bind_phc = phc_index;
891 
892 	return 0;
893 }
894 
895 int sock_set_timestamping(struct sock *sk, int optname,
896 			  struct so_timestamping timestamping)
897 {
898 	int val = timestamping.flags;
899 	int ret;
900 
901 	if (val & ~SOF_TIMESTAMPING_MASK)
902 		return -EINVAL;
903 
904 	if (val & SOF_TIMESTAMPING_OPT_ID &&
905 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
906 		if (sk_is_tcp(sk)) {
907 			if ((1 << sk->sk_state) &
908 			    (TCPF_CLOSE | TCPF_LISTEN))
909 				return -EINVAL;
910 			atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
911 		} else {
912 			atomic_set(&sk->sk_tskey, 0);
913 		}
914 	}
915 
916 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
917 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
918 		return -EINVAL;
919 
920 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
921 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
922 		if (ret)
923 			return ret;
924 	}
925 
926 	sk->sk_tsflags = val;
927 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
928 
929 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
930 		sock_enable_timestamp(sk,
931 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
932 	else
933 		sock_disable_timestamp(sk,
934 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
935 	return 0;
936 }
937 
938 void sock_set_keepalive(struct sock *sk)
939 {
940 	lock_sock(sk);
941 	if (sk->sk_prot->keepalive)
942 		sk->sk_prot->keepalive(sk, true);
943 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
944 	release_sock(sk);
945 }
946 EXPORT_SYMBOL(sock_set_keepalive);
947 
948 static void __sock_set_rcvbuf(struct sock *sk, int val)
949 {
950 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
951 	 * as a negative value.
952 	 */
953 	val = min_t(int, val, INT_MAX / 2);
954 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
955 
956 	/* We double it on the way in to account for "struct sk_buff" etc.
957 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
958 	 * will allow that much actual data to be received on that socket.
959 	 *
960 	 * Applications are unaware that "struct sk_buff" and other overheads
961 	 * allocate from the receive buffer during socket buffer allocation.
962 	 *
963 	 * And after considering the possible alternatives, returning the value
964 	 * we actually used in getsockopt is the most desirable behavior.
965 	 */
966 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
967 }
968 
969 void sock_set_rcvbuf(struct sock *sk, int val)
970 {
971 	lock_sock(sk);
972 	__sock_set_rcvbuf(sk, val);
973 	release_sock(sk);
974 }
975 EXPORT_SYMBOL(sock_set_rcvbuf);
976 
977 static void __sock_set_mark(struct sock *sk, u32 val)
978 {
979 	if (val != sk->sk_mark) {
980 		sk->sk_mark = val;
981 		sk_dst_reset(sk);
982 	}
983 }
984 
985 void sock_set_mark(struct sock *sk, u32 val)
986 {
987 	lock_sock(sk);
988 	__sock_set_mark(sk, val);
989 	release_sock(sk);
990 }
991 EXPORT_SYMBOL(sock_set_mark);
992 
993 static void sock_release_reserved_memory(struct sock *sk, int bytes)
994 {
995 	/* Round down bytes to multiple of pages */
996 	bytes = round_down(bytes, PAGE_SIZE);
997 
998 	WARN_ON(bytes > sk->sk_reserved_mem);
999 	sk->sk_reserved_mem -= bytes;
1000 	sk_mem_reclaim(sk);
1001 }
1002 
1003 static int sock_reserve_memory(struct sock *sk, int bytes)
1004 {
1005 	long allocated;
1006 	bool charged;
1007 	int pages;
1008 
1009 	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1010 		return -EOPNOTSUPP;
1011 
1012 	if (!bytes)
1013 		return 0;
1014 
1015 	pages = sk_mem_pages(bytes);
1016 
1017 	/* pre-charge to memcg */
1018 	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1019 					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1020 	if (!charged)
1021 		return -ENOMEM;
1022 
1023 	/* pre-charge to forward_alloc */
1024 	sk_memory_allocated_add(sk, pages);
1025 	allocated = sk_memory_allocated(sk);
1026 	/* If the system goes into memory pressure with this
1027 	 * precharge, give up and return error.
1028 	 */
1029 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1030 		sk_memory_allocated_sub(sk, pages);
1031 		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1032 		return -ENOMEM;
1033 	}
1034 	sk->sk_forward_alloc += pages << PAGE_SHIFT;
1035 
1036 	sk->sk_reserved_mem += pages << PAGE_SHIFT;
1037 
1038 	return 0;
1039 }
1040 
1041 void sockopt_lock_sock(struct sock *sk)
1042 {
1043 	/* When current->bpf_ctx is set, the setsockopt is called from
1044 	 * a bpf prog.  bpf has ensured the sk lock has been
1045 	 * acquired before calling setsockopt().
1046 	 */
1047 	if (has_current_bpf_ctx())
1048 		return;
1049 
1050 	lock_sock(sk);
1051 }
1052 EXPORT_SYMBOL(sockopt_lock_sock);
1053 
1054 void sockopt_release_sock(struct sock *sk)
1055 {
1056 	if (has_current_bpf_ctx())
1057 		return;
1058 
1059 	release_sock(sk);
1060 }
1061 EXPORT_SYMBOL(sockopt_release_sock);
1062 
1063 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1064 {
1065 	return has_current_bpf_ctx() || ns_capable(ns, cap);
1066 }
1067 EXPORT_SYMBOL(sockopt_ns_capable);
1068 
1069 bool sockopt_capable(int cap)
1070 {
1071 	return has_current_bpf_ctx() || capable(cap);
1072 }
1073 EXPORT_SYMBOL(sockopt_capable);
1074 
1075 /*
1076  *	This is meant for all protocols to use and covers goings on
1077  *	at the socket level. Everything here is generic.
1078  */
1079 
1080 int sk_setsockopt(struct sock *sk, int level, int optname,
1081 		  sockptr_t optval, unsigned int optlen)
1082 {
1083 	struct so_timestamping timestamping;
1084 	struct socket *sock = sk->sk_socket;
1085 	struct sock_txtime sk_txtime;
1086 	int val;
1087 	int valbool;
1088 	struct linger ling;
1089 	int ret = 0;
1090 
1091 	/*
1092 	 *	Options without arguments
1093 	 */
1094 
1095 	if (optname == SO_BINDTODEVICE)
1096 		return sock_setbindtodevice(sk, optval, optlen);
1097 
1098 	if (optlen < sizeof(int))
1099 		return -EINVAL;
1100 
1101 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1102 		return -EFAULT;
1103 
1104 	valbool = val ? 1 : 0;
1105 
1106 	sockopt_lock_sock(sk);
1107 
1108 	switch (optname) {
1109 	case SO_DEBUG:
1110 		if (val && !sockopt_capable(CAP_NET_ADMIN))
1111 			ret = -EACCES;
1112 		else
1113 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1114 		break;
1115 	case SO_REUSEADDR:
1116 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1117 		break;
1118 	case SO_REUSEPORT:
1119 		sk->sk_reuseport = valbool;
1120 		break;
1121 	case SO_TYPE:
1122 	case SO_PROTOCOL:
1123 	case SO_DOMAIN:
1124 	case SO_ERROR:
1125 		ret = -ENOPROTOOPT;
1126 		break;
1127 	case SO_DONTROUTE:
1128 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1129 		sk_dst_reset(sk);
1130 		break;
1131 	case SO_BROADCAST:
1132 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1133 		break;
1134 	case SO_SNDBUF:
1135 		/* Don't error on this BSD doesn't and if you think
1136 		 * about it this is right. Otherwise apps have to
1137 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1138 		 * are treated in BSD as hints
1139 		 */
1140 		val = min_t(u32, val, sysctl_wmem_max);
1141 set_sndbuf:
1142 		/* Ensure val * 2 fits into an int, to prevent max_t()
1143 		 * from treating it as a negative value.
1144 		 */
1145 		val = min_t(int, val, INT_MAX / 2);
1146 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1147 		WRITE_ONCE(sk->sk_sndbuf,
1148 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1149 		/* Wake up sending tasks if we upped the value. */
1150 		sk->sk_write_space(sk);
1151 		break;
1152 
1153 	case SO_SNDBUFFORCE:
1154 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1155 			ret = -EPERM;
1156 			break;
1157 		}
1158 
1159 		/* No negative values (to prevent underflow, as val will be
1160 		 * multiplied by 2).
1161 		 */
1162 		if (val < 0)
1163 			val = 0;
1164 		goto set_sndbuf;
1165 
1166 	case SO_RCVBUF:
1167 		/* Don't error on this BSD doesn't and if you think
1168 		 * about it this is right. Otherwise apps have to
1169 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1170 		 * are treated in BSD as hints
1171 		 */
1172 		__sock_set_rcvbuf(sk, min_t(u32, val, sysctl_rmem_max));
1173 		break;
1174 
1175 	case SO_RCVBUFFORCE:
1176 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1177 			ret = -EPERM;
1178 			break;
1179 		}
1180 
1181 		/* No negative values (to prevent underflow, as val will be
1182 		 * multiplied by 2).
1183 		 */
1184 		__sock_set_rcvbuf(sk, max(val, 0));
1185 		break;
1186 
1187 	case SO_KEEPALIVE:
1188 		if (sk->sk_prot->keepalive)
1189 			sk->sk_prot->keepalive(sk, valbool);
1190 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1191 		break;
1192 
1193 	case SO_OOBINLINE:
1194 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1195 		break;
1196 
1197 	case SO_NO_CHECK:
1198 		sk->sk_no_check_tx = valbool;
1199 		break;
1200 
1201 	case SO_PRIORITY:
1202 		if ((val >= 0 && val <= 6) ||
1203 		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1204 		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1205 			sk->sk_priority = val;
1206 		else
1207 			ret = -EPERM;
1208 		break;
1209 
1210 	case SO_LINGER:
1211 		if (optlen < sizeof(ling)) {
1212 			ret = -EINVAL;	/* 1003.1g */
1213 			break;
1214 		}
1215 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1216 			ret = -EFAULT;
1217 			break;
1218 		}
1219 		if (!ling.l_onoff)
1220 			sock_reset_flag(sk, SOCK_LINGER);
1221 		else {
1222 #if (BITS_PER_LONG == 32)
1223 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
1224 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
1225 			else
1226 #endif
1227 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
1228 			sock_set_flag(sk, SOCK_LINGER);
1229 		}
1230 		break;
1231 
1232 	case SO_BSDCOMPAT:
1233 		break;
1234 
1235 	case SO_PASSCRED:
1236 		if (valbool)
1237 			set_bit(SOCK_PASSCRED, &sock->flags);
1238 		else
1239 			clear_bit(SOCK_PASSCRED, &sock->flags);
1240 		break;
1241 
1242 	case SO_TIMESTAMP_OLD:
1243 	case SO_TIMESTAMP_NEW:
1244 	case SO_TIMESTAMPNS_OLD:
1245 	case SO_TIMESTAMPNS_NEW:
1246 		sock_set_timestamp(sk, optname, valbool);
1247 		break;
1248 
1249 	case SO_TIMESTAMPING_NEW:
1250 	case SO_TIMESTAMPING_OLD:
1251 		if (optlen == sizeof(timestamping)) {
1252 			if (copy_from_sockptr(&timestamping, optval,
1253 					      sizeof(timestamping))) {
1254 				ret = -EFAULT;
1255 				break;
1256 			}
1257 		} else {
1258 			memset(&timestamping, 0, sizeof(timestamping));
1259 			timestamping.flags = val;
1260 		}
1261 		ret = sock_set_timestamping(sk, optname, timestamping);
1262 		break;
1263 
1264 	case SO_RCVLOWAT:
1265 		if (val < 0)
1266 			val = INT_MAX;
1267 		if (sock && sock->ops->set_rcvlowat)
1268 			ret = sock->ops->set_rcvlowat(sk, val);
1269 		else
1270 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1271 		break;
1272 
1273 	case SO_RCVTIMEO_OLD:
1274 	case SO_RCVTIMEO_NEW:
1275 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1276 				       optlen, optname == SO_RCVTIMEO_OLD);
1277 		break;
1278 
1279 	case SO_SNDTIMEO_OLD:
1280 	case SO_SNDTIMEO_NEW:
1281 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1282 				       optlen, optname == SO_SNDTIMEO_OLD);
1283 		break;
1284 
1285 	case SO_ATTACH_FILTER: {
1286 		struct sock_fprog fprog;
1287 
1288 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1289 		if (!ret)
1290 			ret = sk_attach_filter(&fprog, sk);
1291 		break;
1292 	}
1293 	case SO_ATTACH_BPF:
1294 		ret = -EINVAL;
1295 		if (optlen == sizeof(u32)) {
1296 			u32 ufd;
1297 
1298 			ret = -EFAULT;
1299 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1300 				break;
1301 
1302 			ret = sk_attach_bpf(ufd, sk);
1303 		}
1304 		break;
1305 
1306 	case SO_ATTACH_REUSEPORT_CBPF: {
1307 		struct sock_fprog fprog;
1308 
1309 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1310 		if (!ret)
1311 			ret = sk_reuseport_attach_filter(&fprog, sk);
1312 		break;
1313 	}
1314 	case SO_ATTACH_REUSEPORT_EBPF:
1315 		ret = -EINVAL;
1316 		if (optlen == sizeof(u32)) {
1317 			u32 ufd;
1318 
1319 			ret = -EFAULT;
1320 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1321 				break;
1322 
1323 			ret = sk_reuseport_attach_bpf(ufd, sk);
1324 		}
1325 		break;
1326 
1327 	case SO_DETACH_REUSEPORT_BPF:
1328 		ret = reuseport_detach_prog(sk);
1329 		break;
1330 
1331 	case SO_DETACH_FILTER:
1332 		ret = sk_detach_filter(sk);
1333 		break;
1334 
1335 	case SO_LOCK_FILTER:
1336 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1337 			ret = -EPERM;
1338 		else
1339 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1340 		break;
1341 
1342 	case SO_PASSSEC:
1343 		if (valbool)
1344 			set_bit(SOCK_PASSSEC, &sock->flags);
1345 		else
1346 			clear_bit(SOCK_PASSSEC, &sock->flags);
1347 		break;
1348 	case SO_MARK:
1349 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1350 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1351 			ret = -EPERM;
1352 			break;
1353 		}
1354 
1355 		__sock_set_mark(sk, val);
1356 		break;
1357 	case SO_RCVMARK:
1358 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1359 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1360 			ret = -EPERM;
1361 			break;
1362 		}
1363 
1364 		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1365 		break;
1366 
1367 	case SO_RXQ_OVFL:
1368 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1369 		break;
1370 
1371 	case SO_WIFI_STATUS:
1372 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1373 		break;
1374 
1375 	case SO_PEEK_OFF:
1376 		if (sock->ops->set_peek_off)
1377 			ret = sock->ops->set_peek_off(sk, val);
1378 		else
1379 			ret = -EOPNOTSUPP;
1380 		break;
1381 
1382 	case SO_NOFCS:
1383 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1384 		break;
1385 
1386 	case SO_SELECT_ERR_QUEUE:
1387 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1388 		break;
1389 
1390 #ifdef CONFIG_NET_RX_BUSY_POLL
1391 	case SO_BUSY_POLL:
1392 		/* allow unprivileged users to decrease the value */
1393 		if ((val > sk->sk_ll_usec) && !sockopt_capable(CAP_NET_ADMIN))
1394 			ret = -EPERM;
1395 		else {
1396 			if (val < 0)
1397 				ret = -EINVAL;
1398 			else
1399 				WRITE_ONCE(sk->sk_ll_usec, val);
1400 		}
1401 		break;
1402 	case SO_PREFER_BUSY_POLL:
1403 		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1404 			ret = -EPERM;
1405 		else
1406 			WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1407 		break;
1408 	case SO_BUSY_POLL_BUDGET:
1409 		if (val > READ_ONCE(sk->sk_busy_poll_budget) && !sockopt_capable(CAP_NET_ADMIN)) {
1410 			ret = -EPERM;
1411 		} else {
1412 			if (val < 0 || val > U16_MAX)
1413 				ret = -EINVAL;
1414 			else
1415 				WRITE_ONCE(sk->sk_busy_poll_budget, val);
1416 		}
1417 		break;
1418 #endif
1419 
1420 	case SO_MAX_PACING_RATE:
1421 		{
1422 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1423 
1424 		if (sizeof(ulval) != sizeof(val) &&
1425 		    optlen >= sizeof(ulval) &&
1426 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1427 			ret = -EFAULT;
1428 			break;
1429 		}
1430 		if (ulval != ~0UL)
1431 			cmpxchg(&sk->sk_pacing_status,
1432 				SK_PACING_NONE,
1433 				SK_PACING_NEEDED);
1434 		sk->sk_max_pacing_rate = ulval;
1435 		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1436 		break;
1437 		}
1438 	case SO_INCOMING_CPU:
1439 		WRITE_ONCE(sk->sk_incoming_cpu, val);
1440 		break;
1441 
1442 	case SO_CNX_ADVICE:
1443 		if (val == 1)
1444 			dst_negative_advice(sk);
1445 		break;
1446 
1447 	case SO_ZEROCOPY:
1448 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1449 			if (!(sk_is_tcp(sk) ||
1450 			      (sk->sk_type == SOCK_DGRAM &&
1451 			       sk->sk_protocol == IPPROTO_UDP)))
1452 				ret = -EOPNOTSUPP;
1453 		} else if (sk->sk_family != PF_RDS) {
1454 			ret = -EOPNOTSUPP;
1455 		}
1456 		if (!ret) {
1457 			if (val < 0 || val > 1)
1458 				ret = -EINVAL;
1459 			else
1460 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1461 		}
1462 		break;
1463 
1464 	case SO_TXTIME:
1465 		if (optlen != sizeof(struct sock_txtime)) {
1466 			ret = -EINVAL;
1467 			break;
1468 		} else if (copy_from_sockptr(&sk_txtime, optval,
1469 			   sizeof(struct sock_txtime))) {
1470 			ret = -EFAULT;
1471 			break;
1472 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1473 			ret = -EINVAL;
1474 			break;
1475 		}
1476 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1477 		 * scheduler has enough safe guards.
1478 		 */
1479 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1480 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1481 			ret = -EPERM;
1482 			break;
1483 		}
1484 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1485 		sk->sk_clockid = sk_txtime.clockid;
1486 		sk->sk_txtime_deadline_mode =
1487 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1488 		sk->sk_txtime_report_errors =
1489 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1490 		break;
1491 
1492 	case SO_BINDTOIFINDEX:
1493 		ret = sock_bindtoindex_locked(sk, val);
1494 		break;
1495 
1496 	case SO_BUF_LOCK:
1497 		if (val & ~SOCK_BUF_LOCK_MASK) {
1498 			ret = -EINVAL;
1499 			break;
1500 		}
1501 		sk->sk_userlocks = val | (sk->sk_userlocks &
1502 					  ~SOCK_BUF_LOCK_MASK);
1503 		break;
1504 
1505 	case SO_RESERVE_MEM:
1506 	{
1507 		int delta;
1508 
1509 		if (val < 0) {
1510 			ret = -EINVAL;
1511 			break;
1512 		}
1513 
1514 		delta = val - sk->sk_reserved_mem;
1515 		if (delta < 0)
1516 			sock_release_reserved_memory(sk, -delta);
1517 		else
1518 			ret = sock_reserve_memory(sk, delta);
1519 		break;
1520 	}
1521 
1522 	case SO_TXREHASH:
1523 		if (val < -1 || val > 1) {
1524 			ret = -EINVAL;
1525 			break;
1526 		}
1527 		/* Paired with READ_ONCE() in tcp_rtx_synack() */
1528 		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1529 		break;
1530 
1531 	default:
1532 		ret = -ENOPROTOOPT;
1533 		break;
1534 	}
1535 	sockopt_release_sock(sk);
1536 	return ret;
1537 }
1538 
1539 int sock_setsockopt(struct socket *sock, int level, int optname,
1540 		    sockptr_t optval, unsigned int optlen)
1541 {
1542 	return sk_setsockopt(sock->sk, level, optname,
1543 			     optval, optlen);
1544 }
1545 EXPORT_SYMBOL(sock_setsockopt);
1546 
1547 static const struct cred *sk_get_peer_cred(struct sock *sk)
1548 {
1549 	const struct cred *cred;
1550 
1551 	spin_lock(&sk->sk_peer_lock);
1552 	cred = get_cred(sk->sk_peer_cred);
1553 	spin_unlock(&sk->sk_peer_lock);
1554 
1555 	return cred;
1556 }
1557 
1558 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1559 			  struct ucred *ucred)
1560 {
1561 	ucred->pid = pid_vnr(pid);
1562 	ucred->uid = ucred->gid = -1;
1563 	if (cred) {
1564 		struct user_namespace *current_ns = current_user_ns();
1565 
1566 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1567 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1568 	}
1569 }
1570 
1571 static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1572 {
1573 	struct user_namespace *user_ns = current_user_ns();
1574 	int i;
1575 
1576 	for (i = 0; i < src->ngroups; i++)
1577 		if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1578 			return -EFAULT;
1579 
1580 	return 0;
1581 }
1582 
1583 int sock_getsockopt(struct socket *sock, int level, int optname,
1584 		    char __user *optval, int __user *optlen)
1585 {
1586 	struct sock *sk = sock->sk;
1587 
1588 	union {
1589 		int val;
1590 		u64 val64;
1591 		unsigned long ulval;
1592 		struct linger ling;
1593 		struct old_timeval32 tm32;
1594 		struct __kernel_old_timeval tm;
1595 		struct  __kernel_sock_timeval stm;
1596 		struct sock_txtime txtime;
1597 		struct so_timestamping timestamping;
1598 	} v;
1599 
1600 	int lv = sizeof(int);
1601 	int len;
1602 
1603 	if (get_user(len, optlen))
1604 		return -EFAULT;
1605 	if (len < 0)
1606 		return -EINVAL;
1607 
1608 	memset(&v, 0, sizeof(v));
1609 
1610 	switch (optname) {
1611 	case SO_DEBUG:
1612 		v.val = sock_flag(sk, SOCK_DBG);
1613 		break;
1614 
1615 	case SO_DONTROUTE:
1616 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1617 		break;
1618 
1619 	case SO_BROADCAST:
1620 		v.val = sock_flag(sk, SOCK_BROADCAST);
1621 		break;
1622 
1623 	case SO_SNDBUF:
1624 		v.val = sk->sk_sndbuf;
1625 		break;
1626 
1627 	case SO_RCVBUF:
1628 		v.val = sk->sk_rcvbuf;
1629 		break;
1630 
1631 	case SO_REUSEADDR:
1632 		v.val = sk->sk_reuse;
1633 		break;
1634 
1635 	case SO_REUSEPORT:
1636 		v.val = sk->sk_reuseport;
1637 		break;
1638 
1639 	case SO_KEEPALIVE:
1640 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1641 		break;
1642 
1643 	case SO_TYPE:
1644 		v.val = sk->sk_type;
1645 		break;
1646 
1647 	case SO_PROTOCOL:
1648 		v.val = sk->sk_protocol;
1649 		break;
1650 
1651 	case SO_DOMAIN:
1652 		v.val = sk->sk_family;
1653 		break;
1654 
1655 	case SO_ERROR:
1656 		v.val = -sock_error(sk);
1657 		if (v.val == 0)
1658 			v.val = xchg(&sk->sk_err_soft, 0);
1659 		break;
1660 
1661 	case SO_OOBINLINE:
1662 		v.val = sock_flag(sk, SOCK_URGINLINE);
1663 		break;
1664 
1665 	case SO_NO_CHECK:
1666 		v.val = sk->sk_no_check_tx;
1667 		break;
1668 
1669 	case SO_PRIORITY:
1670 		v.val = sk->sk_priority;
1671 		break;
1672 
1673 	case SO_LINGER:
1674 		lv		= sizeof(v.ling);
1675 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1676 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1677 		break;
1678 
1679 	case SO_BSDCOMPAT:
1680 		break;
1681 
1682 	case SO_TIMESTAMP_OLD:
1683 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1684 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1685 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1686 		break;
1687 
1688 	case SO_TIMESTAMPNS_OLD:
1689 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1690 		break;
1691 
1692 	case SO_TIMESTAMP_NEW:
1693 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1694 		break;
1695 
1696 	case SO_TIMESTAMPNS_NEW:
1697 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1698 		break;
1699 
1700 	case SO_TIMESTAMPING_OLD:
1701 		lv = sizeof(v.timestamping);
1702 		v.timestamping.flags = sk->sk_tsflags;
1703 		v.timestamping.bind_phc = sk->sk_bind_phc;
1704 		break;
1705 
1706 	case SO_RCVTIMEO_OLD:
1707 	case SO_RCVTIMEO_NEW:
1708 		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1709 		break;
1710 
1711 	case SO_SNDTIMEO_OLD:
1712 	case SO_SNDTIMEO_NEW:
1713 		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1714 		break;
1715 
1716 	case SO_RCVLOWAT:
1717 		v.val = sk->sk_rcvlowat;
1718 		break;
1719 
1720 	case SO_SNDLOWAT:
1721 		v.val = 1;
1722 		break;
1723 
1724 	case SO_PASSCRED:
1725 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1726 		break;
1727 
1728 	case SO_PEERCRED:
1729 	{
1730 		struct ucred peercred;
1731 		if (len > sizeof(peercred))
1732 			len = sizeof(peercred);
1733 
1734 		spin_lock(&sk->sk_peer_lock);
1735 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1736 		spin_unlock(&sk->sk_peer_lock);
1737 
1738 		if (copy_to_user(optval, &peercred, len))
1739 			return -EFAULT;
1740 		goto lenout;
1741 	}
1742 
1743 	case SO_PEERGROUPS:
1744 	{
1745 		const struct cred *cred;
1746 		int ret, n;
1747 
1748 		cred = sk_get_peer_cred(sk);
1749 		if (!cred)
1750 			return -ENODATA;
1751 
1752 		n = cred->group_info->ngroups;
1753 		if (len < n * sizeof(gid_t)) {
1754 			len = n * sizeof(gid_t);
1755 			put_cred(cred);
1756 			return put_user(len, optlen) ? -EFAULT : -ERANGE;
1757 		}
1758 		len = n * sizeof(gid_t);
1759 
1760 		ret = groups_to_user((gid_t __user *)optval, cred->group_info);
1761 		put_cred(cred);
1762 		if (ret)
1763 			return ret;
1764 		goto lenout;
1765 	}
1766 
1767 	case SO_PEERNAME:
1768 	{
1769 		char address[128];
1770 
1771 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1772 		if (lv < 0)
1773 			return -ENOTCONN;
1774 		if (lv < len)
1775 			return -EINVAL;
1776 		if (copy_to_user(optval, address, len))
1777 			return -EFAULT;
1778 		goto lenout;
1779 	}
1780 
1781 	/* Dubious BSD thing... Probably nobody even uses it, but
1782 	 * the UNIX standard wants it for whatever reason... -DaveM
1783 	 */
1784 	case SO_ACCEPTCONN:
1785 		v.val = sk->sk_state == TCP_LISTEN;
1786 		break;
1787 
1788 	case SO_PASSSEC:
1789 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1790 		break;
1791 
1792 	case SO_PEERSEC:
1793 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1794 
1795 	case SO_MARK:
1796 		v.val = sk->sk_mark;
1797 		break;
1798 
1799 	case SO_RCVMARK:
1800 		v.val = sock_flag(sk, SOCK_RCVMARK);
1801 		break;
1802 
1803 	case SO_RXQ_OVFL:
1804 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1805 		break;
1806 
1807 	case SO_WIFI_STATUS:
1808 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1809 		break;
1810 
1811 	case SO_PEEK_OFF:
1812 		if (!sock->ops->set_peek_off)
1813 			return -EOPNOTSUPP;
1814 
1815 		v.val = sk->sk_peek_off;
1816 		break;
1817 	case SO_NOFCS:
1818 		v.val = sock_flag(sk, SOCK_NOFCS);
1819 		break;
1820 
1821 	case SO_BINDTODEVICE:
1822 		return sock_getbindtodevice(sk, optval, optlen, len);
1823 
1824 	case SO_GET_FILTER:
1825 		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1826 		if (len < 0)
1827 			return len;
1828 
1829 		goto lenout;
1830 
1831 	case SO_LOCK_FILTER:
1832 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1833 		break;
1834 
1835 	case SO_BPF_EXTENSIONS:
1836 		v.val = bpf_tell_extensions();
1837 		break;
1838 
1839 	case SO_SELECT_ERR_QUEUE:
1840 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1841 		break;
1842 
1843 #ifdef CONFIG_NET_RX_BUSY_POLL
1844 	case SO_BUSY_POLL:
1845 		v.val = sk->sk_ll_usec;
1846 		break;
1847 	case SO_PREFER_BUSY_POLL:
1848 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1849 		break;
1850 #endif
1851 
1852 	case SO_MAX_PACING_RATE:
1853 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1854 			lv = sizeof(v.ulval);
1855 			v.ulval = sk->sk_max_pacing_rate;
1856 		} else {
1857 			/* 32bit version */
1858 			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1859 		}
1860 		break;
1861 
1862 	case SO_INCOMING_CPU:
1863 		v.val = READ_ONCE(sk->sk_incoming_cpu);
1864 		break;
1865 
1866 	case SO_MEMINFO:
1867 	{
1868 		u32 meminfo[SK_MEMINFO_VARS];
1869 
1870 		sk_get_meminfo(sk, meminfo);
1871 
1872 		len = min_t(unsigned int, len, sizeof(meminfo));
1873 		if (copy_to_user(optval, &meminfo, len))
1874 			return -EFAULT;
1875 
1876 		goto lenout;
1877 	}
1878 
1879 #ifdef CONFIG_NET_RX_BUSY_POLL
1880 	case SO_INCOMING_NAPI_ID:
1881 		v.val = READ_ONCE(sk->sk_napi_id);
1882 
1883 		/* aggregate non-NAPI IDs down to 0 */
1884 		if (v.val < MIN_NAPI_ID)
1885 			v.val = 0;
1886 
1887 		break;
1888 #endif
1889 
1890 	case SO_COOKIE:
1891 		lv = sizeof(u64);
1892 		if (len < lv)
1893 			return -EINVAL;
1894 		v.val64 = sock_gen_cookie(sk);
1895 		break;
1896 
1897 	case SO_ZEROCOPY:
1898 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1899 		break;
1900 
1901 	case SO_TXTIME:
1902 		lv = sizeof(v.txtime);
1903 		v.txtime.clockid = sk->sk_clockid;
1904 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1905 				  SOF_TXTIME_DEADLINE_MODE : 0;
1906 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1907 				  SOF_TXTIME_REPORT_ERRORS : 0;
1908 		break;
1909 
1910 	case SO_BINDTOIFINDEX:
1911 		v.val = READ_ONCE(sk->sk_bound_dev_if);
1912 		break;
1913 
1914 	case SO_NETNS_COOKIE:
1915 		lv = sizeof(u64);
1916 		if (len != lv)
1917 			return -EINVAL;
1918 		v.val64 = sock_net(sk)->net_cookie;
1919 		break;
1920 
1921 	case SO_BUF_LOCK:
1922 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1923 		break;
1924 
1925 	case SO_RESERVE_MEM:
1926 		v.val = sk->sk_reserved_mem;
1927 		break;
1928 
1929 	case SO_TXREHASH:
1930 		v.val = sk->sk_txrehash;
1931 		break;
1932 
1933 	default:
1934 		/* We implement the SO_SNDLOWAT etc to not be settable
1935 		 * (1003.1g 7).
1936 		 */
1937 		return -ENOPROTOOPT;
1938 	}
1939 
1940 	if (len > lv)
1941 		len = lv;
1942 	if (copy_to_user(optval, &v, len))
1943 		return -EFAULT;
1944 lenout:
1945 	if (put_user(len, optlen))
1946 		return -EFAULT;
1947 	return 0;
1948 }
1949 
1950 /*
1951  * Initialize an sk_lock.
1952  *
1953  * (We also register the sk_lock with the lock validator.)
1954  */
1955 static inline void sock_lock_init(struct sock *sk)
1956 {
1957 	if (sk->sk_kern_sock)
1958 		sock_lock_init_class_and_name(
1959 			sk,
1960 			af_family_kern_slock_key_strings[sk->sk_family],
1961 			af_family_kern_slock_keys + sk->sk_family,
1962 			af_family_kern_key_strings[sk->sk_family],
1963 			af_family_kern_keys + sk->sk_family);
1964 	else
1965 		sock_lock_init_class_and_name(
1966 			sk,
1967 			af_family_slock_key_strings[sk->sk_family],
1968 			af_family_slock_keys + sk->sk_family,
1969 			af_family_key_strings[sk->sk_family],
1970 			af_family_keys + sk->sk_family);
1971 }
1972 
1973 /*
1974  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1975  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1976  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1977  */
1978 static void sock_copy(struct sock *nsk, const struct sock *osk)
1979 {
1980 	const struct proto *prot = READ_ONCE(osk->sk_prot);
1981 #ifdef CONFIG_SECURITY_NETWORK
1982 	void *sptr = nsk->sk_security;
1983 #endif
1984 
1985 	/* If we move sk_tx_queue_mapping out of the private section,
1986 	 * we must check if sk_tx_queue_clear() is called after
1987 	 * sock_copy() in sk_clone_lock().
1988 	 */
1989 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
1990 		     offsetof(struct sock, sk_dontcopy_begin) ||
1991 		     offsetof(struct sock, sk_tx_queue_mapping) >=
1992 		     offsetof(struct sock, sk_dontcopy_end));
1993 
1994 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1995 
1996 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1997 	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1998 
1999 #ifdef CONFIG_SECURITY_NETWORK
2000 	nsk->sk_security = sptr;
2001 	security_sk_clone(osk, nsk);
2002 #endif
2003 }
2004 
2005 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2006 		int family)
2007 {
2008 	struct sock *sk;
2009 	struct kmem_cache *slab;
2010 
2011 	slab = prot->slab;
2012 	if (slab != NULL) {
2013 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2014 		if (!sk)
2015 			return sk;
2016 		if (want_init_on_alloc(priority))
2017 			sk_prot_clear_nulls(sk, prot->obj_size);
2018 	} else
2019 		sk = kmalloc(prot->obj_size, priority);
2020 
2021 	if (sk != NULL) {
2022 		if (security_sk_alloc(sk, family, priority))
2023 			goto out_free;
2024 
2025 		if (!try_module_get(prot->owner))
2026 			goto out_free_sec;
2027 	}
2028 
2029 	return sk;
2030 
2031 out_free_sec:
2032 	security_sk_free(sk);
2033 out_free:
2034 	if (slab != NULL)
2035 		kmem_cache_free(slab, sk);
2036 	else
2037 		kfree(sk);
2038 	return NULL;
2039 }
2040 
2041 static void sk_prot_free(struct proto *prot, struct sock *sk)
2042 {
2043 	struct kmem_cache *slab;
2044 	struct module *owner;
2045 
2046 	owner = prot->owner;
2047 	slab = prot->slab;
2048 
2049 	cgroup_sk_free(&sk->sk_cgrp_data);
2050 	mem_cgroup_sk_free(sk);
2051 	security_sk_free(sk);
2052 	if (slab != NULL)
2053 		kmem_cache_free(slab, sk);
2054 	else
2055 		kfree(sk);
2056 	module_put(owner);
2057 }
2058 
2059 /**
2060  *	sk_alloc - All socket objects are allocated here
2061  *	@net: the applicable net namespace
2062  *	@family: protocol family
2063  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2064  *	@prot: struct proto associated with this new sock instance
2065  *	@kern: is this to be a kernel socket?
2066  */
2067 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2068 		      struct proto *prot, int kern)
2069 {
2070 	struct sock *sk;
2071 
2072 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2073 	if (sk) {
2074 		sk->sk_family = family;
2075 		/*
2076 		 * See comment in struct sock definition to understand
2077 		 * why we need sk_prot_creator -acme
2078 		 */
2079 		sk->sk_prot = sk->sk_prot_creator = prot;
2080 		sk->sk_kern_sock = kern;
2081 		sock_lock_init(sk);
2082 		sk->sk_net_refcnt = kern ? 0 : 1;
2083 		if (likely(sk->sk_net_refcnt)) {
2084 			get_net_track(net, &sk->ns_tracker, priority);
2085 			sock_inuse_add(net, 1);
2086 		}
2087 
2088 		sock_net_set(sk, net);
2089 		refcount_set(&sk->sk_wmem_alloc, 1);
2090 
2091 		mem_cgroup_sk_alloc(sk);
2092 		cgroup_sk_alloc(&sk->sk_cgrp_data);
2093 		sock_update_classid(&sk->sk_cgrp_data);
2094 		sock_update_netprioidx(&sk->sk_cgrp_data);
2095 		sk_tx_queue_clear(sk);
2096 	}
2097 
2098 	return sk;
2099 }
2100 EXPORT_SYMBOL(sk_alloc);
2101 
2102 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2103  * grace period. This is the case for UDP sockets and TCP listeners.
2104  */
2105 static void __sk_destruct(struct rcu_head *head)
2106 {
2107 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2108 	struct sk_filter *filter;
2109 
2110 	if (sk->sk_destruct)
2111 		sk->sk_destruct(sk);
2112 
2113 	filter = rcu_dereference_check(sk->sk_filter,
2114 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2115 	if (filter) {
2116 		sk_filter_uncharge(sk, filter);
2117 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2118 	}
2119 
2120 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2121 
2122 #ifdef CONFIG_BPF_SYSCALL
2123 	bpf_sk_storage_free(sk);
2124 #endif
2125 
2126 	if (atomic_read(&sk->sk_omem_alloc))
2127 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2128 			 __func__, atomic_read(&sk->sk_omem_alloc));
2129 
2130 	if (sk->sk_frag.page) {
2131 		put_page(sk->sk_frag.page);
2132 		sk->sk_frag.page = NULL;
2133 	}
2134 
2135 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2136 	put_cred(sk->sk_peer_cred);
2137 	put_pid(sk->sk_peer_pid);
2138 
2139 	if (likely(sk->sk_net_refcnt))
2140 		put_net_track(sock_net(sk), &sk->ns_tracker);
2141 	sk_prot_free(sk->sk_prot_creator, sk);
2142 }
2143 
2144 void sk_destruct(struct sock *sk)
2145 {
2146 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2147 
2148 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2149 		reuseport_detach_sock(sk);
2150 		use_call_rcu = true;
2151 	}
2152 
2153 	if (use_call_rcu)
2154 		call_rcu(&sk->sk_rcu, __sk_destruct);
2155 	else
2156 		__sk_destruct(&sk->sk_rcu);
2157 }
2158 
2159 static void __sk_free(struct sock *sk)
2160 {
2161 	if (likely(sk->sk_net_refcnt))
2162 		sock_inuse_add(sock_net(sk), -1);
2163 
2164 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2165 		sock_diag_broadcast_destroy(sk);
2166 	else
2167 		sk_destruct(sk);
2168 }
2169 
2170 void sk_free(struct sock *sk)
2171 {
2172 	/*
2173 	 * We subtract one from sk_wmem_alloc and can know if
2174 	 * some packets are still in some tx queue.
2175 	 * If not null, sock_wfree() will call __sk_free(sk) later
2176 	 */
2177 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2178 		__sk_free(sk);
2179 }
2180 EXPORT_SYMBOL(sk_free);
2181 
2182 static void sk_init_common(struct sock *sk)
2183 {
2184 	skb_queue_head_init(&sk->sk_receive_queue);
2185 	skb_queue_head_init(&sk->sk_write_queue);
2186 	skb_queue_head_init(&sk->sk_error_queue);
2187 
2188 	rwlock_init(&sk->sk_callback_lock);
2189 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2190 			af_rlock_keys + sk->sk_family,
2191 			af_family_rlock_key_strings[sk->sk_family]);
2192 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2193 			af_wlock_keys + sk->sk_family,
2194 			af_family_wlock_key_strings[sk->sk_family]);
2195 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2196 			af_elock_keys + sk->sk_family,
2197 			af_family_elock_key_strings[sk->sk_family]);
2198 	lockdep_set_class_and_name(&sk->sk_callback_lock,
2199 			af_callback_keys + sk->sk_family,
2200 			af_family_clock_key_strings[sk->sk_family]);
2201 }
2202 
2203 /**
2204  *	sk_clone_lock - clone a socket, and lock its clone
2205  *	@sk: the socket to clone
2206  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2207  *
2208  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2209  */
2210 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2211 {
2212 	struct proto *prot = READ_ONCE(sk->sk_prot);
2213 	struct sk_filter *filter;
2214 	bool is_charged = true;
2215 	struct sock *newsk;
2216 
2217 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2218 	if (!newsk)
2219 		goto out;
2220 
2221 	sock_copy(newsk, sk);
2222 
2223 	newsk->sk_prot_creator = prot;
2224 
2225 	/* SANITY */
2226 	if (likely(newsk->sk_net_refcnt)) {
2227 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2228 		sock_inuse_add(sock_net(newsk), 1);
2229 	}
2230 	sk_node_init(&newsk->sk_node);
2231 	sock_lock_init(newsk);
2232 	bh_lock_sock(newsk);
2233 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2234 	newsk->sk_backlog.len = 0;
2235 
2236 	atomic_set(&newsk->sk_rmem_alloc, 0);
2237 
2238 	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2239 	refcount_set(&newsk->sk_wmem_alloc, 1);
2240 
2241 	atomic_set(&newsk->sk_omem_alloc, 0);
2242 	sk_init_common(newsk);
2243 
2244 	newsk->sk_dst_cache	= NULL;
2245 	newsk->sk_dst_pending_confirm = 0;
2246 	newsk->sk_wmem_queued	= 0;
2247 	newsk->sk_forward_alloc = 0;
2248 	newsk->sk_reserved_mem  = 0;
2249 	atomic_set(&newsk->sk_drops, 0);
2250 	newsk->sk_send_head	= NULL;
2251 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2252 	atomic_set(&newsk->sk_zckey, 0);
2253 
2254 	sock_reset_flag(newsk, SOCK_DONE);
2255 
2256 	/* sk->sk_memcg will be populated at accept() time */
2257 	newsk->sk_memcg = NULL;
2258 
2259 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2260 
2261 	rcu_read_lock();
2262 	filter = rcu_dereference(sk->sk_filter);
2263 	if (filter != NULL)
2264 		/* though it's an empty new sock, the charging may fail
2265 		 * if sysctl_optmem_max was changed between creation of
2266 		 * original socket and cloning
2267 		 */
2268 		is_charged = sk_filter_charge(newsk, filter);
2269 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2270 	rcu_read_unlock();
2271 
2272 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2273 		/* We need to make sure that we don't uncharge the new
2274 		 * socket if we couldn't charge it in the first place
2275 		 * as otherwise we uncharge the parent's filter.
2276 		 */
2277 		if (!is_charged)
2278 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2279 		sk_free_unlock_clone(newsk);
2280 		newsk = NULL;
2281 		goto out;
2282 	}
2283 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2284 
2285 	if (bpf_sk_storage_clone(sk, newsk)) {
2286 		sk_free_unlock_clone(newsk);
2287 		newsk = NULL;
2288 		goto out;
2289 	}
2290 
2291 	/* Clear sk_user_data if parent had the pointer tagged
2292 	 * as not suitable for copying when cloning.
2293 	 */
2294 	if (sk_user_data_is_nocopy(newsk))
2295 		newsk->sk_user_data = NULL;
2296 
2297 	newsk->sk_err	   = 0;
2298 	newsk->sk_err_soft = 0;
2299 	newsk->sk_priority = 0;
2300 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2301 
2302 	/* Before updating sk_refcnt, we must commit prior changes to memory
2303 	 * (Documentation/RCU/rculist_nulls.rst for details)
2304 	 */
2305 	smp_wmb();
2306 	refcount_set(&newsk->sk_refcnt, 2);
2307 
2308 	/* Increment the counter in the same struct proto as the master
2309 	 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
2310 	 * is the same as sk->sk_prot->socks, as this field was copied
2311 	 * with memcpy).
2312 	 *
2313 	 * This _changes_ the previous behaviour, where
2314 	 * tcp_create_openreq_child always was incrementing the
2315 	 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
2316 	 * to be taken into account in all callers. -acme
2317 	 */
2318 	sk_refcnt_debug_inc(newsk);
2319 	sk_set_socket(newsk, NULL);
2320 	sk_tx_queue_clear(newsk);
2321 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2322 
2323 	if (newsk->sk_prot->sockets_allocated)
2324 		sk_sockets_allocated_inc(newsk);
2325 
2326 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2327 		net_enable_timestamp();
2328 out:
2329 	return newsk;
2330 }
2331 EXPORT_SYMBOL_GPL(sk_clone_lock);
2332 
2333 void sk_free_unlock_clone(struct sock *sk)
2334 {
2335 	/* It is still raw copy of parent, so invalidate
2336 	 * destructor and make plain sk_free() */
2337 	sk->sk_destruct = NULL;
2338 	bh_unlock_sock(sk);
2339 	sk_free(sk);
2340 }
2341 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2342 
2343 static void sk_trim_gso_size(struct sock *sk)
2344 {
2345 	if (sk->sk_gso_max_size <= GSO_LEGACY_MAX_SIZE)
2346 		return;
2347 #if IS_ENABLED(CONFIG_IPV6)
2348 	if (sk->sk_family == AF_INET6 &&
2349 	    sk_is_tcp(sk) &&
2350 	    !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
2351 		return;
2352 #endif
2353 	sk->sk_gso_max_size = GSO_LEGACY_MAX_SIZE;
2354 }
2355 
2356 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2357 {
2358 	u32 max_segs = 1;
2359 
2360 	sk_dst_set(sk, dst);
2361 	sk->sk_route_caps = dst->dev->features;
2362 	if (sk_is_tcp(sk))
2363 		sk->sk_route_caps |= NETIF_F_GSO;
2364 	if (sk->sk_route_caps & NETIF_F_GSO)
2365 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2366 	if (unlikely(sk->sk_gso_disabled))
2367 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2368 	if (sk_can_gso(sk)) {
2369 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2370 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2371 		} else {
2372 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2373 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_size() */
2374 			sk->sk_gso_max_size = READ_ONCE(dst->dev->gso_max_size);
2375 			sk_trim_gso_size(sk);
2376 			sk->sk_gso_max_size -= (MAX_TCP_HEADER + 1);
2377 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2378 			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2379 		}
2380 	}
2381 	sk->sk_gso_max_segs = max_segs;
2382 }
2383 EXPORT_SYMBOL_GPL(sk_setup_caps);
2384 
2385 /*
2386  *	Simple resource managers for sockets.
2387  */
2388 
2389 
2390 /*
2391  * Write buffer destructor automatically called from kfree_skb.
2392  */
2393 void sock_wfree(struct sk_buff *skb)
2394 {
2395 	struct sock *sk = skb->sk;
2396 	unsigned int len = skb->truesize;
2397 	bool free;
2398 
2399 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2400 		if (sock_flag(sk, SOCK_RCU_FREE) &&
2401 		    sk->sk_write_space == sock_def_write_space) {
2402 			rcu_read_lock();
2403 			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2404 			sock_def_write_space_wfree(sk);
2405 			rcu_read_unlock();
2406 			if (unlikely(free))
2407 				__sk_free(sk);
2408 			return;
2409 		}
2410 
2411 		/*
2412 		 * Keep a reference on sk_wmem_alloc, this will be released
2413 		 * after sk_write_space() call
2414 		 */
2415 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2416 		sk->sk_write_space(sk);
2417 		len = 1;
2418 	}
2419 	/*
2420 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2421 	 * could not do because of in-flight packets
2422 	 */
2423 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2424 		__sk_free(sk);
2425 }
2426 EXPORT_SYMBOL(sock_wfree);
2427 
2428 /* This variant of sock_wfree() is used by TCP,
2429  * since it sets SOCK_USE_WRITE_QUEUE.
2430  */
2431 void __sock_wfree(struct sk_buff *skb)
2432 {
2433 	struct sock *sk = skb->sk;
2434 
2435 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2436 		__sk_free(sk);
2437 }
2438 
2439 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2440 {
2441 	skb_orphan(skb);
2442 	skb->sk = sk;
2443 #ifdef CONFIG_INET
2444 	if (unlikely(!sk_fullsock(sk))) {
2445 		skb->destructor = sock_edemux;
2446 		sock_hold(sk);
2447 		return;
2448 	}
2449 #endif
2450 	skb->destructor = sock_wfree;
2451 	skb_set_hash_from_sk(skb, sk);
2452 	/*
2453 	 * We used to take a refcount on sk, but following operation
2454 	 * is enough to guarantee sk_free() wont free this sock until
2455 	 * all in-flight packets are completed
2456 	 */
2457 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2458 }
2459 EXPORT_SYMBOL(skb_set_owner_w);
2460 
2461 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2462 {
2463 #ifdef CONFIG_TLS_DEVICE
2464 	/* Drivers depend on in-order delivery for crypto offload,
2465 	 * partial orphan breaks out-of-order-OK logic.
2466 	 */
2467 	if (skb->decrypted)
2468 		return false;
2469 #endif
2470 	return (skb->destructor == sock_wfree ||
2471 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2472 }
2473 
2474 /* This helper is used by netem, as it can hold packets in its
2475  * delay queue. We want to allow the owner socket to send more
2476  * packets, as if they were already TX completed by a typical driver.
2477  * But we also want to keep skb->sk set because some packet schedulers
2478  * rely on it (sch_fq for example).
2479  */
2480 void skb_orphan_partial(struct sk_buff *skb)
2481 {
2482 	if (skb_is_tcp_pure_ack(skb))
2483 		return;
2484 
2485 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2486 		return;
2487 
2488 	skb_orphan(skb);
2489 }
2490 EXPORT_SYMBOL(skb_orphan_partial);
2491 
2492 /*
2493  * Read buffer destructor automatically called from kfree_skb.
2494  */
2495 void sock_rfree(struct sk_buff *skb)
2496 {
2497 	struct sock *sk = skb->sk;
2498 	unsigned int len = skb->truesize;
2499 
2500 	atomic_sub(len, &sk->sk_rmem_alloc);
2501 	sk_mem_uncharge(sk, len);
2502 }
2503 EXPORT_SYMBOL(sock_rfree);
2504 
2505 /*
2506  * Buffer destructor for skbs that are not used directly in read or write
2507  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2508  */
2509 void sock_efree(struct sk_buff *skb)
2510 {
2511 	sock_put(skb->sk);
2512 }
2513 EXPORT_SYMBOL(sock_efree);
2514 
2515 /* Buffer destructor for prefetch/receive path where reference count may
2516  * not be held, e.g. for listen sockets.
2517  */
2518 #ifdef CONFIG_INET
2519 void sock_pfree(struct sk_buff *skb)
2520 {
2521 	if (sk_is_refcounted(skb->sk))
2522 		sock_gen_put(skb->sk);
2523 }
2524 EXPORT_SYMBOL(sock_pfree);
2525 #endif /* CONFIG_INET */
2526 
2527 kuid_t sock_i_uid(struct sock *sk)
2528 {
2529 	kuid_t uid;
2530 
2531 	read_lock_bh(&sk->sk_callback_lock);
2532 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2533 	read_unlock_bh(&sk->sk_callback_lock);
2534 	return uid;
2535 }
2536 EXPORT_SYMBOL(sock_i_uid);
2537 
2538 unsigned long sock_i_ino(struct sock *sk)
2539 {
2540 	unsigned long ino;
2541 
2542 	read_lock_bh(&sk->sk_callback_lock);
2543 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2544 	read_unlock_bh(&sk->sk_callback_lock);
2545 	return ino;
2546 }
2547 EXPORT_SYMBOL(sock_i_ino);
2548 
2549 /*
2550  * Allocate a skb from the socket's send buffer.
2551  */
2552 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2553 			     gfp_t priority)
2554 {
2555 	if (force ||
2556 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2557 		struct sk_buff *skb = alloc_skb(size, priority);
2558 
2559 		if (skb) {
2560 			skb_set_owner_w(skb, sk);
2561 			return skb;
2562 		}
2563 	}
2564 	return NULL;
2565 }
2566 EXPORT_SYMBOL(sock_wmalloc);
2567 
2568 static void sock_ofree(struct sk_buff *skb)
2569 {
2570 	struct sock *sk = skb->sk;
2571 
2572 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2573 }
2574 
2575 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2576 			     gfp_t priority)
2577 {
2578 	struct sk_buff *skb;
2579 
2580 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2581 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2582 	    sysctl_optmem_max)
2583 		return NULL;
2584 
2585 	skb = alloc_skb(size, priority);
2586 	if (!skb)
2587 		return NULL;
2588 
2589 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2590 	skb->sk = sk;
2591 	skb->destructor = sock_ofree;
2592 	return skb;
2593 }
2594 
2595 /*
2596  * Allocate a memory block from the socket's option memory buffer.
2597  */
2598 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2599 {
2600 	if ((unsigned int)size <= sysctl_optmem_max &&
2601 	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
2602 		void *mem;
2603 		/* First do the add, to avoid the race if kmalloc
2604 		 * might sleep.
2605 		 */
2606 		atomic_add(size, &sk->sk_omem_alloc);
2607 		mem = kmalloc(size, priority);
2608 		if (mem)
2609 			return mem;
2610 		atomic_sub(size, &sk->sk_omem_alloc);
2611 	}
2612 	return NULL;
2613 }
2614 EXPORT_SYMBOL(sock_kmalloc);
2615 
2616 /* Free an option memory block. Note, we actually want the inline
2617  * here as this allows gcc to detect the nullify and fold away the
2618  * condition entirely.
2619  */
2620 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2621 				  const bool nullify)
2622 {
2623 	if (WARN_ON_ONCE(!mem))
2624 		return;
2625 	if (nullify)
2626 		kfree_sensitive(mem);
2627 	else
2628 		kfree(mem);
2629 	atomic_sub(size, &sk->sk_omem_alloc);
2630 }
2631 
2632 void sock_kfree_s(struct sock *sk, void *mem, int size)
2633 {
2634 	__sock_kfree_s(sk, mem, size, false);
2635 }
2636 EXPORT_SYMBOL(sock_kfree_s);
2637 
2638 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2639 {
2640 	__sock_kfree_s(sk, mem, size, true);
2641 }
2642 EXPORT_SYMBOL(sock_kzfree_s);
2643 
2644 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2645    I think, these locks should be removed for datagram sockets.
2646  */
2647 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2648 {
2649 	DEFINE_WAIT(wait);
2650 
2651 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2652 	for (;;) {
2653 		if (!timeo)
2654 			break;
2655 		if (signal_pending(current))
2656 			break;
2657 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2658 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2659 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2660 			break;
2661 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2662 			break;
2663 		if (sk->sk_err)
2664 			break;
2665 		timeo = schedule_timeout(timeo);
2666 	}
2667 	finish_wait(sk_sleep(sk), &wait);
2668 	return timeo;
2669 }
2670 
2671 
2672 /*
2673  *	Generic send/receive buffer handlers
2674  */
2675 
2676 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2677 				     unsigned long data_len, int noblock,
2678 				     int *errcode, int max_page_order)
2679 {
2680 	struct sk_buff *skb;
2681 	long timeo;
2682 	int err;
2683 
2684 	timeo = sock_sndtimeo(sk, noblock);
2685 	for (;;) {
2686 		err = sock_error(sk);
2687 		if (err != 0)
2688 			goto failure;
2689 
2690 		err = -EPIPE;
2691 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2692 			goto failure;
2693 
2694 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2695 			break;
2696 
2697 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2698 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2699 		err = -EAGAIN;
2700 		if (!timeo)
2701 			goto failure;
2702 		if (signal_pending(current))
2703 			goto interrupted;
2704 		timeo = sock_wait_for_wmem(sk, timeo);
2705 	}
2706 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2707 				   errcode, sk->sk_allocation);
2708 	if (skb)
2709 		skb_set_owner_w(skb, sk);
2710 	return skb;
2711 
2712 interrupted:
2713 	err = sock_intr_errno(timeo);
2714 failure:
2715 	*errcode = err;
2716 	return NULL;
2717 }
2718 EXPORT_SYMBOL(sock_alloc_send_pskb);
2719 
2720 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2721 		     struct sockcm_cookie *sockc)
2722 {
2723 	u32 tsflags;
2724 
2725 	switch (cmsg->cmsg_type) {
2726 	case SO_MARK:
2727 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2728 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2729 			return -EPERM;
2730 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2731 			return -EINVAL;
2732 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2733 		break;
2734 	case SO_TIMESTAMPING_OLD:
2735 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2736 			return -EINVAL;
2737 
2738 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2739 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2740 			return -EINVAL;
2741 
2742 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2743 		sockc->tsflags |= tsflags;
2744 		break;
2745 	case SCM_TXTIME:
2746 		if (!sock_flag(sk, SOCK_TXTIME))
2747 			return -EINVAL;
2748 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2749 			return -EINVAL;
2750 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2751 		break;
2752 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2753 	case SCM_RIGHTS:
2754 	case SCM_CREDENTIALS:
2755 		break;
2756 	default:
2757 		return -EINVAL;
2758 	}
2759 	return 0;
2760 }
2761 EXPORT_SYMBOL(__sock_cmsg_send);
2762 
2763 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2764 		   struct sockcm_cookie *sockc)
2765 {
2766 	struct cmsghdr *cmsg;
2767 	int ret;
2768 
2769 	for_each_cmsghdr(cmsg, msg) {
2770 		if (!CMSG_OK(msg, cmsg))
2771 			return -EINVAL;
2772 		if (cmsg->cmsg_level != SOL_SOCKET)
2773 			continue;
2774 		ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2775 		if (ret)
2776 			return ret;
2777 	}
2778 	return 0;
2779 }
2780 EXPORT_SYMBOL(sock_cmsg_send);
2781 
2782 static void sk_enter_memory_pressure(struct sock *sk)
2783 {
2784 	if (!sk->sk_prot->enter_memory_pressure)
2785 		return;
2786 
2787 	sk->sk_prot->enter_memory_pressure(sk);
2788 }
2789 
2790 static void sk_leave_memory_pressure(struct sock *sk)
2791 {
2792 	if (sk->sk_prot->leave_memory_pressure) {
2793 		sk->sk_prot->leave_memory_pressure(sk);
2794 	} else {
2795 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2796 
2797 		if (memory_pressure && READ_ONCE(*memory_pressure))
2798 			WRITE_ONCE(*memory_pressure, 0);
2799 	}
2800 }
2801 
2802 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2803 
2804 /**
2805  * skb_page_frag_refill - check that a page_frag contains enough room
2806  * @sz: minimum size of the fragment we want to get
2807  * @pfrag: pointer to page_frag
2808  * @gfp: priority for memory allocation
2809  *
2810  * Note: While this allocator tries to use high order pages, there is
2811  * no guarantee that allocations succeed. Therefore, @sz MUST be
2812  * less or equal than PAGE_SIZE.
2813  */
2814 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2815 {
2816 	if (pfrag->page) {
2817 		if (page_ref_count(pfrag->page) == 1) {
2818 			pfrag->offset = 0;
2819 			return true;
2820 		}
2821 		if (pfrag->offset + sz <= pfrag->size)
2822 			return true;
2823 		put_page(pfrag->page);
2824 	}
2825 
2826 	pfrag->offset = 0;
2827 	if (SKB_FRAG_PAGE_ORDER &&
2828 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2829 		/* Avoid direct reclaim but allow kswapd to wake */
2830 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2831 					  __GFP_COMP | __GFP_NOWARN |
2832 					  __GFP_NORETRY,
2833 					  SKB_FRAG_PAGE_ORDER);
2834 		if (likely(pfrag->page)) {
2835 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2836 			return true;
2837 		}
2838 	}
2839 	pfrag->page = alloc_page(gfp);
2840 	if (likely(pfrag->page)) {
2841 		pfrag->size = PAGE_SIZE;
2842 		return true;
2843 	}
2844 	return false;
2845 }
2846 EXPORT_SYMBOL(skb_page_frag_refill);
2847 
2848 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2849 {
2850 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2851 		return true;
2852 
2853 	sk_enter_memory_pressure(sk);
2854 	sk_stream_moderate_sndbuf(sk);
2855 	return false;
2856 }
2857 EXPORT_SYMBOL(sk_page_frag_refill);
2858 
2859 void __lock_sock(struct sock *sk)
2860 	__releases(&sk->sk_lock.slock)
2861 	__acquires(&sk->sk_lock.slock)
2862 {
2863 	DEFINE_WAIT(wait);
2864 
2865 	for (;;) {
2866 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2867 					TASK_UNINTERRUPTIBLE);
2868 		spin_unlock_bh(&sk->sk_lock.slock);
2869 		schedule();
2870 		spin_lock_bh(&sk->sk_lock.slock);
2871 		if (!sock_owned_by_user(sk))
2872 			break;
2873 	}
2874 	finish_wait(&sk->sk_lock.wq, &wait);
2875 }
2876 
2877 void __release_sock(struct sock *sk)
2878 	__releases(&sk->sk_lock.slock)
2879 	__acquires(&sk->sk_lock.slock)
2880 {
2881 	struct sk_buff *skb, *next;
2882 
2883 	while ((skb = sk->sk_backlog.head) != NULL) {
2884 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2885 
2886 		spin_unlock_bh(&sk->sk_lock.slock);
2887 
2888 		do {
2889 			next = skb->next;
2890 			prefetch(next);
2891 			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2892 			skb_mark_not_on_list(skb);
2893 			sk_backlog_rcv(sk, skb);
2894 
2895 			cond_resched();
2896 
2897 			skb = next;
2898 		} while (skb != NULL);
2899 
2900 		spin_lock_bh(&sk->sk_lock.slock);
2901 	}
2902 
2903 	/*
2904 	 * Doing the zeroing here guarantee we can not loop forever
2905 	 * while a wild producer attempts to flood us.
2906 	 */
2907 	sk->sk_backlog.len = 0;
2908 }
2909 
2910 void __sk_flush_backlog(struct sock *sk)
2911 {
2912 	spin_lock_bh(&sk->sk_lock.slock);
2913 	__release_sock(sk);
2914 	spin_unlock_bh(&sk->sk_lock.slock);
2915 }
2916 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
2917 
2918 /**
2919  * sk_wait_data - wait for data to arrive at sk_receive_queue
2920  * @sk:    sock to wait on
2921  * @timeo: for how long
2922  * @skb:   last skb seen on sk_receive_queue
2923  *
2924  * Now socket state including sk->sk_err is changed only under lock,
2925  * hence we may omit checks after joining wait queue.
2926  * We check receive queue before schedule() only as optimization;
2927  * it is very likely that release_sock() added new data.
2928  */
2929 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2930 {
2931 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2932 	int rc;
2933 
2934 	add_wait_queue(sk_sleep(sk), &wait);
2935 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2936 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2937 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2938 	remove_wait_queue(sk_sleep(sk), &wait);
2939 	return rc;
2940 }
2941 EXPORT_SYMBOL(sk_wait_data);
2942 
2943 /**
2944  *	__sk_mem_raise_allocated - increase memory_allocated
2945  *	@sk: socket
2946  *	@size: memory size to allocate
2947  *	@amt: pages to allocate
2948  *	@kind: allocation type
2949  *
2950  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2951  */
2952 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2953 {
2954 	bool memcg_charge = mem_cgroup_sockets_enabled && sk->sk_memcg;
2955 	struct proto *prot = sk->sk_prot;
2956 	bool charged = true;
2957 	long allocated;
2958 
2959 	sk_memory_allocated_add(sk, amt);
2960 	allocated = sk_memory_allocated(sk);
2961 	if (memcg_charge &&
2962 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt,
2963 						gfp_memcg_charge())))
2964 		goto suppress_allocation;
2965 
2966 	/* Under limit. */
2967 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2968 		sk_leave_memory_pressure(sk);
2969 		return 1;
2970 	}
2971 
2972 	/* Under pressure. */
2973 	if (allocated > sk_prot_mem_limits(sk, 1))
2974 		sk_enter_memory_pressure(sk);
2975 
2976 	/* Over hard limit. */
2977 	if (allocated > sk_prot_mem_limits(sk, 2))
2978 		goto suppress_allocation;
2979 
2980 	/* guarantee minimum buffer size under pressure */
2981 	if (kind == SK_MEM_RECV) {
2982 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2983 			return 1;
2984 
2985 	} else { /* SK_MEM_SEND */
2986 		int wmem0 = sk_get_wmem0(sk, prot);
2987 
2988 		if (sk->sk_type == SOCK_STREAM) {
2989 			if (sk->sk_wmem_queued < wmem0)
2990 				return 1;
2991 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
2992 				return 1;
2993 		}
2994 	}
2995 
2996 	if (sk_has_memory_pressure(sk)) {
2997 		u64 alloc;
2998 
2999 		if (!sk_under_memory_pressure(sk))
3000 			return 1;
3001 		alloc = sk_sockets_allocated_read_positive(sk);
3002 		if (sk_prot_mem_limits(sk, 2) > alloc *
3003 		    sk_mem_pages(sk->sk_wmem_queued +
3004 				 atomic_read(&sk->sk_rmem_alloc) +
3005 				 sk->sk_forward_alloc))
3006 			return 1;
3007 	}
3008 
3009 suppress_allocation:
3010 
3011 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3012 		sk_stream_moderate_sndbuf(sk);
3013 
3014 		/* Fail only if socket is _under_ its sndbuf.
3015 		 * In this case we cannot block, so that we have to fail.
3016 		 */
3017 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3018 			/* Force charge with __GFP_NOFAIL */
3019 			if (memcg_charge && !charged) {
3020 				mem_cgroup_charge_skmem(sk->sk_memcg, amt,
3021 					gfp_memcg_charge() | __GFP_NOFAIL);
3022 			}
3023 			return 1;
3024 		}
3025 	}
3026 
3027 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3028 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3029 
3030 	sk_memory_allocated_sub(sk, amt);
3031 
3032 	if (memcg_charge && charged)
3033 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
3034 
3035 	return 0;
3036 }
3037 
3038 /**
3039  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3040  *	@sk: socket
3041  *	@size: memory size to allocate
3042  *	@kind: allocation type
3043  *
3044  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3045  *	rmem allocation. This function assumes that protocols which have
3046  *	memory_pressure use sk_wmem_queued as write buffer accounting.
3047  */
3048 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3049 {
3050 	int ret, amt = sk_mem_pages(size);
3051 
3052 	sk->sk_forward_alloc += amt << PAGE_SHIFT;
3053 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3054 	if (!ret)
3055 		sk->sk_forward_alloc -= amt << PAGE_SHIFT;
3056 	return ret;
3057 }
3058 EXPORT_SYMBOL(__sk_mem_schedule);
3059 
3060 /**
3061  *	__sk_mem_reduce_allocated - reclaim memory_allocated
3062  *	@sk: socket
3063  *	@amount: number of quanta
3064  *
3065  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3066  */
3067 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3068 {
3069 	sk_memory_allocated_sub(sk, amount);
3070 
3071 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3072 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3073 
3074 	if (sk_under_memory_pressure(sk) &&
3075 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3076 		sk_leave_memory_pressure(sk);
3077 }
3078 
3079 /**
3080  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3081  *	@sk: socket
3082  *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3083  */
3084 void __sk_mem_reclaim(struct sock *sk, int amount)
3085 {
3086 	amount >>= PAGE_SHIFT;
3087 	sk->sk_forward_alloc -= amount << PAGE_SHIFT;
3088 	__sk_mem_reduce_allocated(sk, amount);
3089 }
3090 EXPORT_SYMBOL(__sk_mem_reclaim);
3091 
3092 int sk_set_peek_off(struct sock *sk, int val)
3093 {
3094 	sk->sk_peek_off = val;
3095 	return 0;
3096 }
3097 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3098 
3099 /*
3100  * Set of default routines for initialising struct proto_ops when
3101  * the protocol does not support a particular function. In certain
3102  * cases where it makes no sense for a protocol to have a "do nothing"
3103  * function, some default processing is provided.
3104  */
3105 
3106 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3107 {
3108 	return -EOPNOTSUPP;
3109 }
3110 EXPORT_SYMBOL(sock_no_bind);
3111 
3112 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3113 		    int len, int flags)
3114 {
3115 	return -EOPNOTSUPP;
3116 }
3117 EXPORT_SYMBOL(sock_no_connect);
3118 
3119 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3120 {
3121 	return -EOPNOTSUPP;
3122 }
3123 EXPORT_SYMBOL(sock_no_socketpair);
3124 
3125 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3126 		   bool kern)
3127 {
3128 	return -EOPNOTSUPP;
3129 }
3130 EXPORT_SYMBOL(sock_no_accept);
3131 
3132 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3133 		    int peer)
3134 {
3135 	return -EOPNOTSUPP;
3136 }
3137 EXPORT_SYMBOL(sock_no_getname);
3138 
3139 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3140 {
3141 	return -EOPNOTSUPP;
3142 }
3143 EXPORT_SYMBOL(sock_no_ioctl);
3144 
3145 int sock_no_listen(struct socket *sock, int backlog)
3146 {
3147 	return -EOPNOTSUPP;
3148 }
3149 EXPORT_SYMBOL(sock_no_listen);
3150 
3151 int sock_no_shutdown(struct socket *sock, int how)
3152 {
3153 	return -EOPNOTSUPP;
3154 }
3155 EXPORT_SYMBOL(sock_no_shutdown);
3156 
3157 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3158 {
3159 	return -EOPNOTSUPP;
3160 }
3161 EXPORT_SYMBOL(sock_no_sendmsg);
3162 
3163 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3164 {
3165 	return -EOPNOTSUPP;
3166 }
3167 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3168 
3169 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3170 		    int flags)
3171 {
3172 	return -EOPNOTSUPP;
3173 }
3174 EXPORT_SYMBOL(sock_no_recvmsg);
3175 
3176 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3177 {
3178 	/* Mirror missing mmap method error code */
3179 	return -ENODEV;
3180 }
3181 EXPORT_SYMBOL(sock_no_mmap);
3182 
3183 /*
3184  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3185  * various sock-based usage counts.
3186  */
3187 void __receive_sock(struct file *file)
3188 {
3189 	struct socket *sock;
3190 
3191 	sock = sock_from_file(file);
3192 	if (sock) {
3193 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3194 		sock_update_classid(&sock->sk->sk_cgrp_data);
3195 	}
3196 }
3197 
3198 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
3199 {
3200 	ssize_t res;
3201 	struct msghdr msg = {.msg_flags = flags};
3202 	struct kvec iov;
3203 	char *kaddr = kmap(page);
3204 	iov.iov_base = kaddr + offset;
3205 	iov.iov_len = size;
3206 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
3207 	kunmap(page);
3208 	return res;
3209 }
3210 EXPORT_SYMBOL(sock_no_sendpage);
3211 
3212 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
3213 				int offset, size_t size, int flags)
3214 {
3215 	ssize_t res;
3216 	struct msghdr msg = {.msg_flags = flags};
3217 	struct kvec iov;
3218 	char *kaddr = kmap(page);
3219 
3220 	iov.iov_base = kaddr + offset;
3221 	iov.iov_len = size;
3222 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
3223 	kunmap(page);
3224 	return res;
3225 }
3226 EXPORT_SYMBOL(sock_no_sendpage_locked);
3227 
3228 /*
3229  *	Default Socket Callbacks
3230  */
3231 
3232 static void sock_def_wakeup(struct sock *sk)
3233 {
3234 	struct socket_wq *wq;
3235 
3236 	rcu_read_lock();
3237 	wq = rcu_dereference(sk->sk_wq);
3238 	if (skwq_has_sleeper(wq))
3239 		wake_up_interruptible_all(&wq->wait);
3240 	rcu_read_unlock();
3241 }
3242 
3243 static void sock_def_error_report(struct sock *sk)
3244 {
3245 	struct socket_wq *wq;
3246 
3247 	rcu_read_lock();
3248 	wq = rcu_dereference(sk->sk_wq);
3249 	if (skwq_has_sleeper(wq))
3250 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3251 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3252 	rcu_read_unlock();
3253 }
3254 
3255 void sock_def_readable(struct sock *sk)
3256 {
3257 	struct socket_wq *wq;
3258 
3259 	rcu_read_lock();
3260 	wq = rcu_dereference(sk->sk_wq);
3261 	if (skwq_has_sleeper(wq))
3262 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3263 						EPOLLRDNORM | EPOLLRDBAND);
3264 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3265 	rcu_read_unlock();
3266 }
3267 
3268 static void sock_def_write_space(struct sock *sk)
3269 {
3270 	struct socket_wq *wq;
3271 
3272 	rcu_read_lock();
3273 
3274 	/* Do not wake up a writer until he can make "significant"
3275 	 * progress.  --DaveM
3276 	 */
3277 	if (sock_writeable(sk)) {
3278 		wq = rcu_dereference(sk->sk_wq);
3279 		if (skwq_has_sleeper(wq))
3280 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3281 						EPOLLWRNORM | EPOLLWRBAND);
3282 
3283 		/* Should agree with poll, otherwise some programs break */
3284 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3285 	}
3286 
3287 	rcu_read_unlock();
3288 }
3289 
3290 /* An optimised version of sock_def_write_space(), should only be called
3291  * for SOCK_RCU_FREE sockets under RCU read section and after putting
3292  * ->sk_wmem_alloc.
3293  */
3294 static void sock_def_write_space_wfree(struct sock *sk)
3295 {
3296 	/* Do not wake up a writer until he can make "significant"
3297 	 * progress.  --DaveM
3298 	 */
3299 	if (sock_writeable(sk)) {
3300 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3301 
3302 		/* rely on refcount_sub from sock_wfree() */
3303 		smp_mb__after_atomic();
3304 		if (wq && waitqueue_active(&wq->wait))
3305 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3306 						EPOLLWRNORM | EPOLLWRBAND);
3307 
3308 		/* Should agree with poll, otherwise some programs break */
3309 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3310 	}
3311 }
3312 
3313 static void sock_def_destruct(struct sock *sk)
3314 {
3315 }
3316 
3317 void sk_send_sigurg(struct sock *sk)
3318 {
3319 	if (sk->sk_socket && sk->sk_socket->file)
3320 		if (send_sigurg(&sk->sk_socket->file->f_owner))
3321 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3322 }
3323 EXPORT_SYMBOL(sk_send_sigurg);
3324 
3325 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3326 		    unsigned long expires)
3327 {
3328 	if (!mod_timer(timer, expires))
3329 		sock_hold(sk);
3330 }
3331 EXPORT_SYMBOL(sk_reset_timer);
3332 
3333 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3334 {
3335 	if (del_timer(timer))
3336 		__sock_put(sk);
3337 }
3338 EXPORT_SYMBOL(sk_stop_timer);
3339 
3340 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3341 {
3342 	if (del_timer_sync(timer))
3343 		__sock_put(sk);
3344 }
3345 EXPORT_SYMBOL(sk_stop_timer_sync);
3346 
3347 void sock_init_data(struct socket *sock, struct sock *sk)
3348 {
3349 	sk_init_common(sk);
3350 	sk->sk_send_head	=	NULL;
3351 
3352 	timer_setup(&sk->sk_timer, NULL, 0);
3353 
3354 	sk->sk_allocation	=	GFP_KERNEL;
3355 	sk->sk_rcvbuf		=	sysctl_rmem_default;
3356 	sk->sk_sndbuf		=	sysctl_wmem_default;
3357 	sk->sk_state		=	TCP_CLOSE;
3358 	sk_set_socket(sk, sock);
3359 
3360 	sock_set_flag(sk, SOCK_ZAPPED);
3361 
3362 	if (sock) {
3363 		sk->sk_type	=	sock->type;
3364 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3365 		sock->sk	=	sk;
3366 		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
3367 	} else {
3368 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3369 		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
3370 	}
3371 
3372 	rwlock_init(&sk->sk_callback_lock);
3373 	if (sk->sk_kern_sock)
3374 		lockdep_set_class_and_name(
3375 			&sk->sk_callback_lock,
3376 			af_kern_callback_keys + sk->sk_family,
3377 			af_family_kern_clock_key_strings[sk->sk_family]);
3378 	else
3379 		lockdep_set_class_and_name(
3380 			&sk->sk_callback_lock,
3381 			af_callback_keys + sk->sk_family,
3382 			af_family_clock_key_strings[sk->sk_family]);
3383 
3384 	sk->sk_state_change	=	sock_def_wakeup;
3385 	sk->sk_data_ready	=	sock_def_readable;
3386 	sk->sk_write_space	=	sock_def_write_space;
3387 	sk->sk_error_report	=	sock_def_error_report;
3388 	sk->sk_destruct		=	sock_def_destruct;
3389 
3390 	sk->sk_frag.page	=	NULL;
3391 	sk->sk_frag.offset	=	0;
3392 	sk->sk_peek_off		=	-1;
3393 
3394 	sk->sk_peer_pid 	=	NULL;
3395 	sk->sk_peer_cred	=	NULL;
3396 	spin_lock_init(&sk->sk_peer_lock);
3397 
3398 	sk->sk_write_pending	=	0;
3399 	sk->sk_rcvlowat		=	1;
3400 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3401 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3402 
3403 	sk->sk_stamp = SK_DEFAULT_STAMP;
3404 #if BITS_PER_LONG==32
3405 	seqlock_init(&sk->sk_stamp_seq);
3406 #endif
3407 	atomic_set(&sk->sk_zckey, 0);
3408 
3409 #ifdef CONFIG_NET_RX_BUSY_POLL
3410 	sk->sk_napi_id		=	0;
3411 	sk->sk_ll_usec		=	sysctl_net_busy_read;
3412 #endif
3413 
3414 	sk->sk_max_pacing_rate = ~0UL;
3415 	sk->sk_pacing_rate = ~0UL;
3416 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3417 	sk->sk_incoming_cpu = -1;
3418 	sk->sk_txrehash = SOCK_TXREHASH_DEFAULT;
3419 
3420 	sk_rx_queue_clear(sk);
3421 	/*
3422 	 * Before updating sk_refcnt, we must commit prior changes to memory
3423 	 * (Documentation/RCU/rculist_nulls.rst for details)
3424 	 */
3425 	smp_wmb();
3426 	refcount_set(&sk->sk_refcnt, 1);
3427 	atomic_set(&sk->sk_drops, 0);
3428 }
3429 EXPORT_SYMBOL(sock_init_data);
3430 
3431 void lock_sock_nested(struct sock *sk, int subclass)
3432 {
3433 	/* The sk_lock has mutex_lock() semantics here. */
3434 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3435 
3436 	might_sleep();
3437 	spin_lock_bh(&sk->sk_lock.slock);
3438 	if (sock_owned_by_user_nocheck(sk))
3439 		__lock_sock(sk);
3440 	sk->sk_lock.owned = 1;
3441 	spin_unlock_bh(&sk->sk_lock.slock);
3442 }
3443 EXPORT_SYMBOL(lock_sock_nested);
3444 
3445 void release_sock(struct sock *sk)
3446 {
3447 	spin_lock_bh(&sk->sk_lock.slock);
3448 	if (sk->sk_backlog.tail)
3449 		__release_sock(sk);
3450 
3451 	/* Warning : release_cb() might need to release sk ownership,
3452 	 * ie call sock_release_ownership(sk) before us.
3453 	 */
3454 	if (sk->sk_prot->release_cb)
3455 		sk->sk_prot->release_cb(sk);
3456 
3457 	sock_release_ownership(sk);
3458 	if (waitqueue_active(&sk->sk_lock.wq))
3459 		wake_up(&sk->sk_lock.wq);
3460 	spin_unlock_bh(&sk->sk_lock.slock);
3461 }
3462 EXPORT_SYMBOL(release_sock);
3463 
3464 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3465 {
3466 	might_sleep();
3467 	spin_lock_bh(&sk->sk_lock.slock);
3468 
3469 	if (!sock_owned_by_user_nocheck(sk)) {
3470 		/*
3471 		 * Fast path return with bottom halves disabled and
3472 		 * sock::sk_lock.slock held.
3473 		 *
3474 		 * The 'mutex' is not contended and holding
3475 		 * sock::sk_lock.slock prevents all other lockers to
3476 		 * proceed so the corresponding unlock_sock_fast() can
3477 		 * avoid the slow path of release_sock() completely and
3478 		 * just release slock.
3479 		 *
3480 		 * From a semantical POV this is equivalent to 'acquiring'
3481 		 * the 'mutex', hence the corresponding lockdep
3482 		 * mutex_release() has to happen in the fast path of
3483 		 * unlock_sock_fast().
3484 		 */
3485 		return false;
3486 	}
3487 
3488 	__lock_sock(sk);
3489 	sk->sk_lock.owned = 1;
3490 	__acquire(&sk->sk_lock.slock);
3491 	spin_unlock_bh(&sk->sk_lock.slock);
3492 	return true;
3493 }
3494 EXPORT_SYMBOL(__lock_sock_fast);
3495 
3496 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3497 		   bool timeval, bool time32)
3498 {
3499 	struct sock *sk = sock->sk;
3500 	struct timespec64 ts;
3501 
3502 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3503 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3504 	if (ts.tv_sec == -1)
3505 		return -ENOENT;
3506 	if (ts.tv_sec == 0) {
3507 		ktime_t kt = ktime_get_real();
3508 		sock_write_timestamp(sk, kt);
3509 		ts = ktime_to_timespec64(kt);
3510 	}
3511 
3512 	if (timeval)
3513 		ts.tv_nsec /= 1000;
3514 
3515 #ifdef CONFIG_COMPAT_32BIT_TIME
3516 	if (time32)
3517 		return put_old_timespec32(&ts, userstamp);
3518 #endif
3519 #ifdef CONFIG_SPARC64
3520 	/* beware of padding in sparc64 timeval */
3521 	if (timeval && !in_compat_syscall()) {
3522 		struct __kernel_old_timeval __user tv = {
3523 			.tv_sec = ts.tv_sec,
3524 			.tv_usec = ts.tv_nsec,
3525 		};
3526 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3527 			return -EFAULT;
3528 		return 0;
3529 	}
3530 #endif
3531 	return put_timespec64(&ts, userstamp);
3532 }
3533 EXPORT_SYMBOL(sock_gettstamp);
3534 
3535 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3536 {
3537 	if (!sock_flag(sk, flag)) {
3538 		unsigned long previous_flags = sk->sk_flags;
3539 
3540 		sock_set_flag(sk, flag);
3541 		/*
3542 		 * we just set one of the two flags which require net
3543 		 * time stamping, but time stamping might have been on
3544 		 * already because of the other one
3545 		 */
3546 		if (sock_needs_netstamp(sk) &&
3547 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3548 			net_enable_timestamp();
3549 	}
3550 }
3551 
3552 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3553 		       int level, int type)
3554 {
3555 	struct sock_exterr_skb *serr;
3556 	struct sk_buff *skb;
3557 	int copied, err;
3558 
3559 	err = -EAGAIN;
3560 	skb = sock_dequeue_err_skb(sk);
3561 	if (skb == NULL)
3562 		goto out;
3563 
3564 	copied = skb->len;
3565 	if (copied > len) {
3566 		msg->msg_flags |= MSG_TRUNC;
3567 		copied = len;
3568 	}
3569 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3570 	if (err)
3571 		goto out_free_skb;
3572 
3573 	sock_recv_timestamp(msg, sk, skb);
3574 
3575 	serr = SKB_EXT_ERR(skb);
3576 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3577 
3578 	msg->msg_flags |= MSG_ERRQUEUE;
3579 	err = copied;
3580 
3581 out_free_skb:
3582 	kfree_skb(skb);
3583 out:
3584 	return err;
3585 }
3586 EXPORT_SYMBOL(sock_recv_errqueue);
3587 
3588 /*
3589  *	Get a socket option on an socket.
3590  *
3591  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3592  *	asynchronous errors should be reported by getsockopt. We assume
3593  *	this means if you specify SO_ERROR (otherwise whats the point of it).
3594  */
3595 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3596 			   char __user *optval, int __user *optlen)
3597 {
3598 	struct sock *sk = sock->sk;
3599 
3600 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3601 }
3602 EXPORT_SYMBOL(sock_common_getsockopt);
3603 
3604 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3605 			int flags)
3606 {
3607 	struct sock *sk = sock->sk;
3608 	int addr_len = 0;
3609 	int err;
3610 
3611 	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3612 	if (err >= 0)
3613 		msg->msg_namelen = addr_len;
3614 	return err;
3615 }
3616 EXPORT_SYMBOL(sock_common_recvmsg);
3617 
3618 /*
3619  *	Set socket options on an inet socket.
3620  */
3621 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3622 			   sockptr_t optval, unsigned int optlen)
3623 {
3624 	struct sock *sk = sock->sk;
3625 
3626 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3627 }
3628 EXPORT_SYMBOL(sock_common_setsockopt);
3629 
3630 void sk_common_release(struct sock *sk)
3631 {
3632 	if (sk->sk_prot->destroy)
3633 		sk->sk_prot->destroy(sk);
3634 
3635 	/*
3636 	 * Observation: when sk_common_release is called, processes have
3637 	 * no access to socket. But net still has.
3638 	 * Step one, detach it from networking:
3639 	 *
3640 	 * A. Remove from hash tables.
3641 	 */
3642 
3643 	sk->sk_prot->unhash(sk);
3644 
3645 	/*
3646 	 * In this point socket cannot receive new packets, but it is possible
3647 	 * that some packets are in flight because some CPU runs receiver and
3648 	 * did hash table lookup before we unhashed socket. They will achieve
3649 	 * receive queue and will be purged by socket destructor.
3650 	 *
3651 	 * Also we still have packets pending on receive queue and probably,
3652 	 * our own packets waiting in device queues. sock_destroy will drain
3653 	 * receive queue, but transmitted packets will delay socket destruction
3654 	 * until the last reference will be released.
3655 	 */
3656 
3657 	sock_orphan(sk);
3658 
3659 	xfrm_sk_free_policy(sk);
3660 
3661 	sk_refcnt_debug_release(sk);
3662 
3663 	sock_put(sk);
3664 }
3665 EXPORT_SYMBOL(sk_common_release);
3666 
3667 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3668 {
3669 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3670 
3671 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3672 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3673 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3674 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3675 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3676 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3677 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3678 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3679 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3680 }
3681 
3682 #ifdef CONFIG_PROC_FS
3683 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3684 
3685 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3686 {
3687 	int cpu, idx = prot->inuse_idx;
3688 	int res = 0;
3689 
3690 	for_each_possible_cpu(cpu)
3691 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3692 
3693 	return res >= 0 ? res : 0;
3694 }
3695 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3696 
3697 int sock_inuse_get(struct net *net)
3698 {
3699 	int cpu, res = 0;
3700 
3701 	for_each_possible_cpu(cpu)
3702 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3703 
3704 	return res;
3705 }
3706 
3707 EXPORT_SYMBOL_GPL(sock_inuse_get);
3708 
3709 static int __net_init sock_inuse_init_net(struct net *net)
3710 {
3711 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3712 	if (net->core.prot_inuse == NULL)
3713 		return -ENOMEM;
3714 	return 0;
3715 }
3716 
3717 static void __net_exit sock_inuse_exit_net(struct net *net)
3718 {
3719 	free_percpu(net->core.prot_inuse);
3720 }
3721 
3722 static struct pernet_operations net_inuse_ops = {
3723 	.init = sock_inuse_init_net,
3724 	.exit = sock_inuse_exit_net,
3725 };
3726 
3727 static __init int net_inuse_init(void)
3728 {
3729 	if (register_pernet_subsys(&net_inuse_ops))
3730 		panic("Cannot initialize net inuse counters");
3731 
3732 	return 0;
3733 }
3734 
3735 core_initcall(net_inuse_init);
3736 
3737 static int assign_proto_idx(struct proto *prot)
3738 {
3739 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3740 
3741 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3742 		pr_err("PROTO_INUSE_NR exhausted\n");
3743 		return -ENOSPC;
3744 	}
3745 
3746 	set_bit(prot->inuse_idx, proto_inuse_idx);
3747 	return 0;
3748 }
3749 
3750 static void release_proto_idx(struct proto *prot)
3751 {
3752 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3753 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3754 }
3755 #else
3756 static inline int assign_proto_idx(struct proto *prot)
3757 {
3758 	return 0;
3759 }
3760 
3761 static inline void release_proto_idx(struct proto *prot)
3762 {
3763 }
3764 
3765 #endif
3766 
3767 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3768 {
3769 	if (!twsk_prot)
3770 		return;
3771 	kfree(twsk_prot->twsk_slab_name);
3772 	twsk_prot->twsk_slab_name = NULL;
3773 	kmem_cache_destroy(twsk_prot->twsk_slab);
3774 	twsk_prot->twsk_slab = NULL;
3775 }
3776 
3777 static int tw_prot_init(const struct proto *prot)
3778 {
3779 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3780 
3781 	if (!twsk_prot)
3782 		return 0;
3783 
3784 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3785 					      prot->name);
3786 	if (!twsk_prot->twsk_slab_name)
3787 		return -ENOMEM;
3788 
3789 	twsk_prot->twsk_slab =
3790 		kmem_cache_create(twsk_prot->twsk_slab_name,
3791 				  twsk_prot->twsk_obj_size, 0,
3792 				  SLAB_ACCOUNT | prot->slab_flags,
3793 				  NULL);
3794 	if (!twsk_prot->twsk_slab) {
3795 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3796 			prot->name);
3797 		return -ENOMEM;
3798 	}
3799 
3800 	return 0;
3801 }
3802 
3803 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3804 {
3805 	if (!rsk_prot)
3806 		return;
3807 	kfree(rsk_prot->slab_name);
3808 	rsk_prot->slab_name = NULL;
3809 	kmem_cache_destroy(rsk_prot->slab);
3810 	rsk_prot->slab = NULL;
3811 }
3812 
3813 static int req_prot_init(const struct proto *prot)
3814 {
3815 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3816 
3817 	if (!rsk_prot)
3818 		return 0;
3819 
3820 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3821 					prot->name);
3822 	if (!rsk_prot->slab_name)
3823 		return -ENOMEM;
3824 
3825 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3826 					   rsk_prot->obj_size, 0,
3827 					   SLAB_ACCOUNT | prot->slab_flags,
3828 					   NULL);
3829 
3830 	if (!rsk_prot->slab) {
3831 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3832 			prot->name);
3833 		return -ENOMEM;
3834 	}
3835 	return 0;
3836 }
3837 
3838 int proto_register(struct proto *prot, int alloc_slab)
3839 {
3840 	int ret = -ENOBUFS;
3841 
3842 	if (prot->memory_allocated && !prot->sysctl_mem) {
3843 		pr_err("%s: missing sysctl_mem\n", prot->name);
3844 		return -EINVAL;
3845 	}
3846 	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
3847 		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
3848 		return -EINVAL;
3849 	}
3850 	if (alloc_slab) {
3851 		prot->slab = kmem_cache_create_usercopy(prot->name,
3852 					prot->obj_size, 0,
3853 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3854 					prot->slab_flags,
3855 					prot->useroffset, prot->usersize,
3856 					NULL);
3857 
3858 		if (prot->slab == NULL) {
3859 			pr_crit("%s: Can't create sock SLAB cache!\n",
3860 				prot->name);
3861 			goto out;
3862 		}
3863 
3864 		if (req_prot_init(prot))
3865 			goto out_free_request_sock_slab;
3866 
3867 		if (tw_prot_init(prot))
3868 			goto out_free_timewait_sock_slab;
3869 	}
3870 
3871 	mutex_lock(&proto_list_mutex);
3872 	ret = assign_proto_idx(prot);
3873 	if (ret) {
3874 		mutex_unlock(&proto_list_mutex);
3875 		goto out_free_timewait_sock_slab;
3876 	}
3877 	list_add(&prot->node, &proto_list);
3878 	mutex_unlock(&proto_list_mutex);
3879 	return ret;
3880 
3881 out_free_timewait_sock_slab:
3882 	if (alloc_slab)
3883 		tw_prot_cleanup(prot->twsk_prot);
3884 out_free_request_sock_slab:
3885 	if (alloc_slab) {
3886 		req_prot_cleanup(prot->rsk_prot);
3887 
3888 		kmem_cache_destroy(prot->slab);
3889 		prot->slab = NULL;
3890 	}
3891 out:
3892 	return ret;
3893 }
3894 EXPORT_SYMBOL(proto_register);
3895 
3896 void proto_unregister(struct proto *prot)
3897 {
3898 	mutex_lock(&proto_list_mutex);
3899 	release_proto_idx(prot);
3900 	list_del(&prot->node);
3901 	mutex_unlock(&proto_list_mutex);
3902 
3903 	kmem_cache_destroy(prot->slab);
3904 	prot->slab = NULL;
3905 
3906 	req_prot_cleanup(prot->rsk_prot);
3907 	tw_prot_cleanup(prot->twsk_prot);
3908 }
3909 EXPORT_SYMBOL(proto_unregister);
3910 
3911 int sock_load_diag_module(int family, int protocol)
3912 {
3913 	if (!protocol) {
3914 		if (!sock_is_registered(family))
3915 			return -ENOENT;
3916 
3917 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3918 				      NETLINK_SOCK_DIAG, family);
3919 	}
3920 
3921 #ifdef CONFIG_INET
3922 	if (family == AF_INET &&
3923 	    protocol != IPPROTO_RAW &&
3924 	    protocol < MAX_INET_PROTOS &&
3925 	    !rcu_access_pointer(inet_protos[protocol]))
3926 		return -ENOENT;
3927 #endif
3928 
3929 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3930 			      NETLINK_SOCK_DIAG, family, protocol);
3931 }
3932 EXPORT_SYMBOL(sock_load_diag_module);
3933 
3934 #ifdef CONFIG_PROC_FS
3935 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3936 	__acquires(proto_list_mutex)
3937 {
3938 	mutex_lock(&proto_list_mutex);
3939 	return seq_list_start_head(&proto_list, *pos);
3940 }
3941 
3942 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3943 {
3944 	return seq_list_next(v, &proto_list, pos);
3945 }
3946 
3947 static void proto_seq_stop(struct seq_file *seq, void *v)
3948 	__releases(proto_list_mutex)
3949 {
3950 	mutex_unlock(&proto_list_mutex);
3951 }
3952 
3953 static char proto_method_implemented(const void *method)
3954 {
3955 	return method == NULL ? 'n' : 'y';
3956 }
3957 static long sock_prot_memory_allocated(struct proto *proto)
3958 {
3959 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3960 }
3961 
3962 static const char *sock_prot_memory_pressure(struct proto *proto)
3963 {
3964 	return proto->memory_pressure != NULL ?
3965 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3966 }
3967 
3968 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3969 {
3970 
3971 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
3972 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3973 		   proto->name,
3974 		   proto->obj_size,
3975 		   sock_prot_inuse_get(seq_file_net(seq), proto),
3976 		   sock_prot_memory_allocated(proto),
3977 		   sock_prot_memory_pressure(proto),
3978 		   proto->max_header,
3979 		   proto->slab == NULL ? "no" : "yes",
3980 		   module_name(proto->owner),
3981 		   proto_method_implemented(proto->close),
3982 		   proto_method_implemented(proto->connect),
3983 		   proto_method_implemented(proto->disconnect),
3984 		   proto_method_implemented(proto->accept),
3985 		   proto_method_implemented(proto->ioctl),
3986 		   proto_method_implemented(proto->init),
3987 		   proto_method_implemented(proto->destroy),
3988 		   proto_method_implemented(proto->shutdown),
3989 		   proto_method_implemented(proto->setsockopt),
3990 		   proto_method_implemented(proto->getsockopt),
3991 		   proto_method_implemented(proto->sendmsg),
3992 		   proto_method_implemented(proto->recvmsg),
3993 		   proto_method_implemented(proto->sendpage),
3994 		   proto_method_implemented(proto->bind),
3995 		   proto_method_implemented(proto->backlog_rcv),
3996 		   proto_method_implemented(proto->hash),
3997 		   proto_method_implemented(proto->unhash),
3998 		   proto_method_implemented(proto->get_port),
3999 		   proto_method_implemented(proto->enter_memory_pressure));
4000 }
4001 
4002 static int proto_seq_show(struct seq_file *seq, void *v)
4003 {
4004 	if (v == &proto_list)
4005 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4006 			   "protocol",
4007 			   "size",
4008 			   "sockets",
4009 			   "memory",
4010 			   "press",
4011 			   "maxhdr",
4012 			   "slab",
4013 			   "module",
4014 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
4015 	else
4016 		proto_seq_printf(seq, list_entry(v, struct proto, node));
4017 	return 0;
4018 }
4019 
4020 static const struct seq_operations proto_seq_ops = {
4021 	.start  = proto_seq_start,
4022 	.next   = proto_seq_next,
4023 	.stop   = proto_seq_stop,
4024 	.show   = proto_seq_show,
4025 };
4026 
4027 static __net_init int proto_init_net(struct net *net)
4028 {
4029 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4030 			sizeof(struct seq_net_private)))
4031 		return -ENOMEM;
4032 
4033 	return 0;
4034 }
4035 
4036 static __net_exit void proto_exit_net(struct net *net)
4037 {
4038 	remove_proc_entry("protocols", net->proc_net);
4039 }
4040 
4041 
4042 static __net_initdata struct pernet_operations proto_net_ops = {
4043 	.init = proto_init_net,
4044 	.exit = proto_exit_net,
4045 };
4046 
4047 static int __init proto_init(void)
4048 {
4049 	return register_pernet_subsys(&proto_net_ops);
4050 }
4051 
4052 subsys_initcall(proto_init);
4053 
4054 #endif /* PROC_FS */
4055 
4056 #ifdef CONFIG_NET_RX_BUSY_POLL
4057 bool sk_busy_loop_end(void *p, unsigned long start_time)
4058 {
4059 	struct sock *sk = p;
4060 
4061 	return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
4062 	       sk_busy_loop_timeout(sk, start_time);
4063 }
4064 EXPORT_SYMBOL(sk_busy_loop_end);
4065 #endif /* CONFIG_NET_RX_BUSY_POLL */
4066 
4067 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4068 {
4069 	if (!sk->sk_prot->bind_add)
4070 		return -EOPNOTSUPP;
4071 	return sk->sk_prot->bind_add(sk, addr, addr_len);
4072 }
4073 EXPORT_SYMBOL(sock_bind_add);
4074