xref: /openbmc/linux/net/core/sock.c (revision 9d5dbfe0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * INET		An implementation of the TCP/IP protocol suite for the LINUX
4  *		operating system.  INET is implemented using the  BSD Socket
5  *		interface as the means of communication with the user level.
6  *
7  *		Generic socket support routines. Memory allocators, socket lock/release
8  *		handler for protocols to use and generic option handler.
9  *
10  * Authors:	Ross Biro
11  *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12  *		Florian La Roche, <flla@stud.uni-sb.de>
13  *		Alan Cox, <A.Cox@swansea.ac.uk>
14  *
15  * Fixes:
16  *		Alan Cox	: 	Numerous verify_area() problems
17  *		Alan Cox	:	Connecting on a connecting socket
18  *					now returns an error for tcp.
19  *		Alan Cox	:	sock->protocol is set correctly.
20  *					and is not sometimes left as 0.
21  *		Alan Cox	:	connect handles icmp errors on a
22  *					connect properly. Unfortunately there
23  *					is a restart syscall nasty there. I
24  *					can't match BSD without hacking the C
25  *					library. Ideas urgently sought!
26  *		Alan Cox	:	Disallow bind() to addresses that are
27  *					not ours - especially broadcast ones!!
28  *		Alan Cox	:	Socket 1024 _IS_ ok for users. (fencepost)
29  *		Alan Cox	:	sock_wfree/sock_rfree don't destroy sockets,
30  *					instead they leave that for the DESTROY timer.
31  *		Alan Cox	:	Clean up error flag in accept
32  *		Alan Cox	:	TCP ack handling is buggy, the DESTROY timer
33  *					was buggy. Put a remove_sock() in the handler
34  *					for memory when we hit 0. Also altered the timer
35  *					code. The ACK stuff can wait and needs major
36  *					TCP layer surgery.
37  *		Alan Cox	:	Fixed TCP ack bug, removed remove sock
38  *					and fixed timer/inet_bh race.
39  *		Alan Cox	:	Added zapped flag for TCP
40  *		Alan Cox	:	Move kfree_skb into skbuff.c and tidied up surplus code
41  *		Alan Cox	:	for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42  *		Alan Cox	:	kfree_s calls now are kfree_skbmem so we can track skb resources
43  *		Alan Cox	:	Supports socket option broadcast now as does udp. Packet and raw need fixing.
44  *		Alan Cox	:	Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45  *		Rick Sladkey	:	Relaxed UDP rules for matching packets.
46  *		C.E.Hawkins	:	IFF_PROMISC/SIOCGHWADDR support
47  *	Pauline Middelink	:	identd support
48  *		Alan Cox	:	Fixed connect() taking signals I think.
49  *		Alan Cox	:	SO_LINGER supported
50  *		Alan Cox	:	Error reporting fixes
51  *		Anonymous	:	inet_create tidied up (sk->reuse setting)
52  *		Alan Cox	:	inet sockets don't set sk->type!
53  *		Alan Cox	:	Split socket option code
54  *		Alan Cox	:	Callbacks
55  *		Alan Cox	:	Nagle flag for Charles & Johannes stuff
56  *		Alex		:	Removed restriction on inet fioctl
57  *		Alan Cox	:	Splitting INET from NET core
58  *		Alan Cox	:	Fixed bogus SO_TYPE handling in getsockopt()
59  *		Adam Caldwell	:	Missing return in SO_DONTROUTE/SO_DEBUG code
60  *		Alan Cox	:	Split IP from generic code
61  *		Alan Cox	:	New kfree_skbmem()
62  *		Alan Cox	:	Make SO_DEBUG superuser only.
63  *		Alan Cox	:	Allow anyone to clear SO_DEBUG
64  *					(compatibility fix)
65  *		Alan Cox	:	Added optimistic memory grabbing for AF_UNIX throughput.
66  *		Alan Cox	:	Allocator for a socket is settable.
67  *		Alan Cox	:	SO_ERROR includes soft errors.
68  *		Alan Cox	:	Allow NULL arguments on some SO_ opts
69  *		Alan Cox	: 	Generic socket allocation to make hooks
70  *					easier (suggested by Craig Metz).
71  *		Michael Pall	:	SO_ERROR returns positive errno again
72  *              Steve Whitehouse:       Added default destructor to free
73  *                                      protocol private data.
74  *              Steve Whitehouse:       Added various other default routines
75  *                                      common to several socket families.
76  *              Chris Evans     :       Call suser() check last on F_SETOWN
77  *		Jay Schulist	:	Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78  *		Andi Kleen	:	Add sock_kmalloc()/sock_kfree_s()
79  *		Andi Kleen	:	Fix write_space callback
80  *		Chris Evans	:	Security fixes - signedness again
81  *		Arnaldo C. Melo :       cleanups, use skb_queue_purge
82  *
83  * To Fix:
84  */
85 
86 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
87 
88 #include <asm/unaligned.h>
89 #include <linux/capability.h>
90 #include <linux/errno.h>
91 #include <linux/errqueue.h>
92 #include <linux/types.h>
93 #include <linux/socket.h>
94 #include <linux/in.h>
95 #include <linux/kernel.h>
96 #include <linux/module.h>
97 #include <linux/proc_fs.h>
98 #include <linux/seq_file.h>
99 #include <linux/sched.h>
100 #include <linux/sched/mm.h>
101 #include <linux/timer.h>
102 #include <linux/string.h>
103 #include <linux/sockios.h>
104 #include <linux/net.h>
105 #include <linux/mm.h>
106 #include <linux/slab.h>
107 #include <linux/interrupt.h>
108 #include <linux/poll.h>
109 #include <linux/tcp.h>
110 #include <linux/init.h>
111 #include <linux/highmem.h>
112 #include <linux/user_namespace.h>
113 #include <linux/static_key.h>
114 #include <linux/memcontrol.h>
115 #include <linux/prefetch.h>
116 #include <linux/compat.h>
117 
118 #include <linux/uaccess.h>
119 
120 #include <linux/netdevice.h>
121 #include <net/protocol.h>
122 #include <linux/skbuff.h>
123 #include <net/net_namespace.h>
124 #include <net/request_sock.h>
125 #include <net/sock.h>
126 #include <linux/net_tstamp.h>
127 #include <net/xfrm.h>
128 #include <linux/ipsec.h>
129 #include <net/cls_cgroup.h>
130 #include <net/netprio_cgroup.h>
131 #include <linux/sock_diag.h>
132 
133 #include <linux/filter.h>
134 #include <net/sock_reuseport.h>
135 #include <net/bpf_sk_storage.h>
136 
137 #include <trace/events/sock.h>
138 
139 #include <net/tcp.h>
140 #include <net/busy_poll.h>
141 
142 #include <linux/ethtool.h>
143 
144 #include "dev.h"
145 
146 static DEFINE_MUTEX(proto_list_mutex);
147 static LIST_HEAD(proto_list);
148 
149 static void sock_def_write_space_wfree(struct sock *sk);
150 static void sock_def_write_space(struct sock *sk);
151 
152 /**
153  * sk_ns_capable - General socket capability test
154  * @sk: Socket to use a capability on or through
155  * @user_ns: The user namespace of the capability to use
156  * @cap: The capability to use
157  *
158  * Test to see if the opener of the socket had when the socket was
159  * created and the current process has the capability @cap in the user
160  * namespace @user_ns.
161  */
162 bool sk_ns_capable(const struct sock *sk,
163 		   struct user_namespace *user_ns, int cap)
164 {
165 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
166 		ns_capable(user_ns, cap);
167 }
168 EXPORT_SYMBOL(sk_ns_capable);
169 
170 /**
171  * sk_capable - Socket global capability test
172  * @sk: Socket to use a capability on or through
173  * @cap: The global capability to use
174  *
175  * Test to see if the opener of the socket had when the socket was
176  * created and the current process has the capability @cap in all user
177  * namespaces.
178  */
179 bool sk_capable(const struct sock *sk, int cap)
180 {
181 	return sk_ns_capable(sk, &init_user_ns, cap);
182 }
183 EXPORT_SYMBOL(sk_capable);
184 
185 /**
186  * sk_net_capable - Network namespace socket capability test
187  * @sk: Socket to use a capability on or through
188  * @cap: The capability to use
189  *
190  * Test to see if the opener of the socket had when the socket was created
191  * and the current process has the capability @cap over the network namespace
192  * the socket is a member of.
193  */
194 bool sk_net_capable(const struct sock *sk, int cap)
195 {
196 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
197 }
198 EXPORT_SYMBOL(sk_net_capable);
199 
200 /*
201  * Each address family might have different locking rules, so we have
202  * one slock key per address family and separate keys for internal and
203  * userspace sockets.
204  */
205 static struct lock_class_key af_family_keys[AF_MAX];
206 static struct lock_class_key af_family_kern_keys[AF_MAX];
207 static struct lock_class_key af_family_slock_keys[AF_MAX];
208 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
209 
210 /*
211  * Make lock validator output more readable. (we pre-construct these
212  * strings build-time, so that runtime initialization of socket
213  * locks is fast):
214  */
215 
216 #define _sock_locks(x)						  \
217   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
218   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
219   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
220   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
221   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
222   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
223   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
224   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
225   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
226   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
227   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
228   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
229   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
230   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
231   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
232   x "AF_MCTP"  , \
233   x "AF_MAX"
234 
235 static const char *const af_family_key_strings[AF_MAX+1] = {
236 	_sock_locks("sk_lock-")
237 };
238 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
239 	_sock_locks("slock-")
240 };
241 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
242 	_sock_locks("clock-")
243 };
244 
245 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
246 	_sock_locks("k-sk_lock-")
247 };
248 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
249 	_sock_locks("k-slock-")
250 };
251 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
252 	_sock_locks("k-clock-")
253 };
254 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
255 	_sock_locks("rlock-")
256 };
257 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
258 	_sock_locks("wlock-")
259 };
260 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
261 	_sock_locks("elock-")
262 };
263 
264 /*
265  * sk_callback_lock and sk queues locking rules are per-address-family,
266  * so split the lock classes by using a per-AF key:
267  */
268 static struct lock_class_key af_callback_keys[AF_MAX];
269 static struct lock_class_key af_rlock_keys[AF_MAX];
270 static struct lock_class_key af_wlock_keys[AF_MAX];
271 static struct lock_class_key af_elock_keys[AF_MAX];
272 static struct lock_class_key af_kern_callback_keys[AF_MAX];
273 
274 /* Run time adjustable parameters. */
275 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
276 EXPORT_SYMBOL(sysctl_wmem_max);
277 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
278 EXPORT_SYMBOL(sysctl_rmem_max);
279 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
280 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
281 
282 /* Maximal space eaten by iovec or ancillary data plus some space */
283 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
284 EXPORT_SYMBOL(sysctl_optmem_max);
285 
286 int sysctl_tstamp_allow_data __read_mostly = 1;
287 
288 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
289 EXPORT_SYMBOL_GPL(memalloc_socks_key);
290 
291 /**
292  * sk_set_memalloc - sets %SOCK_MEMALLOC
293  * @sk: socket to set it on
294  *
295  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
296  * It's the responsibility of the admin to adjust min_free_kbytes
297  * to meet the requirements
298  */
299 void sk_set_memalloc(struct sock *sk)
300 {
301 	sock_set_flag(sk, SOCK_MEMALLOC);
302 	sk->sk_allocation |= __GFP_MEMALLOC;
303 	static_branch_inc(&memalloc_socks_key);
304 }
305 EXPORT_SYMBOL_GPL(sk_set_memalloc);
306 
307 void sk_clear_memalloc(struct sock *sk)
308 {
309 	sock_reset_flag(sk, SOCK_MEMALLOC);
310 	sk->sk_allocation &= ~__GFP_MEMALLOC;
311 	static_branch_dec(&memalloc_socks_key);
312 
313 	/*
314 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
315 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
316 	 * it has rmem allocations due to the last swapfile being deactivated
317 	 * but there is a risk that the socket is unusable due to exceeding
318 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
319 	 */
320 	sk_mem_reclaim(sk);
321 }
322 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
323 
324 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
325 {
326 	int ret;
327 	unsigned int noreclaim_flag;
328 
329 	/* these should have been dropped before queueing */
330 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
331 
332 	noreclaim_flag = memalloc_noreclaim_save();
333 	ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
334 				 tcp_v6_do_rcv,
335 				 tcp_v4_do_rcv,
336 				 sk, skb);
337 	memalloc_noreclaim_restore(noreclaim_flag);
338 
339 	return ret;
340 }
341 EXPORT_SYMBOL(__sk_backlog_rcv);
342 
343 void sk_error_report(struct sock *sk)
344 {
345 	sk->sk_error_report(sk);
346 
347 	switch (sk->sk_family) {
348 	case AF_INET:
349 		fallthrough;
350 	case AF_INET6:
351 		trace_inet_sk_error_report(sk);
352 		break;
353 	default:
354 		break;
355 	}
356 }
357 EXPORT_SYMBOL(sk_error_report);
358 
359 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
360 {
361 	struct __kernel_sock_timeval tv;
362 
363 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
364 		tv.tv_sec = 0;
365 		tv.tv_usec = 0;
366 	} else {
367 		tv.tv_sec = timeo / HZ;
368 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
369 	}
370 
371 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
372 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
373 		*(struct old_timeval32 *)optval = tv32;
374 		return sizeof(tv32);
375 	}
376 
377 	if (old_timeval) {
378 		struct __kernel_old_timeval old_tv;
379 		old_tv.tv_sec = tv.tv_sec;
380 		old_tv.tv_usec = tv.tv_usec;
381 		*(struct __kernel_old_timeval *)optval = old_tv;
382 		return sizeof(old_tv);
383 	}
384 
385 	*(struct __kernel_sock_timeval *)optval = tv;
386 	return sizeof(tv);
387 }
388 EXPORT_SYMBOL(sock_get_timeout);
389 
390 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
391 			   sockptr_t optval, int optlen, bool old_timeval)
392 {
393 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
394 		struct old_timeval32 tv32;
395 
396 		if (optlen < sizeof(tv32))
397 			return -EINVAL;
398 
399 		if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
400 			return -EFAULT;
401 		tv->tv_sec = tv32.tv_sec;
402 		tv->tv_usec = tv32.tv_usec;
403 	} else if (old_timeval) {
404 		struct __kernel_old_timeval old_tv;
405 
406 		if (optlen < sizeof(old_tv))
407 			return -EINVAL;
408 		if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
409 			return -EFAULT;
410 		tv->tv_sec = old_tv.tv_sec;
411 		tv->tv_usec = old_tv.tv_usec;
412 	} else {
413 		if (optlen < sizeof(*tv))
414 			return -EINVAL;
415 		if (copy_from_sockptr(tv, optval, sizeof(*tv)))
416 			return -EFAULT;
417 	}
418 
419 	return 0;
420 }
421 EXPORT_SYMBOL(sock_copy_user_timeval);
422 
423 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
424 			    bool old_timeval)
425 {
426 	struct __kernel_sock_timeval tv;
427 	int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
428 
429 	if (err)
430 		return err;
431 
432 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
433 		return -EDOM;
434 
435 	if (tv.tv_sec < 0) {
436 		static int warned __read_mostly;
437 
438 		*timeo_p = 0;
439 		if (warned < 10 && net_ratelimit()) {
440 			warned++;
441 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
442 				__func__, current->comm, task_pid_nr(current));
443 		}
444 		return 0;
445 	}
446 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
447 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
448 		return 0;
449 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
450 		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
451 	return 0;
452 }
453 
454 static bool sock_needs_netstamp(const struct sock *sk)
455 {
456 	switch (sk->sk_family) {
457 	case AF_UNSPEC:
458 	case AF_UNIX:
459 		return false;
460 	default:
461 		return true;
462 	}
463 }
464 
465 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
466 {
467 	if (sk->sk_flags & flags) {
468 		sk->sk_flags &= ~flags;
469 		if (sock_needs_netstamp(sk) &&
470 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
471 			net_disable_timestamp();
472 	}
473 }
474 
475 
476 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
477 {
478 	unsigned long flags;
479 	struct sk_buff_head *list = &sk->sk_receive_queue;
480 
481 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
482 		atomic_inc(&sk->sk_drops);
483 		trace_sock_rcvqueue_full(sk, skb);
484 		return -ENOMEM;
485 	}
486 
487 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
488 		atomic_inc(&sk->sk_drops);
489 		return -ENOBUFS;
490 	}
491 
492 	skb->dev = NULL;
493 	skb_set_owner_r(skb, sk);
494 
495 	/* we escape from rcu protected region, make sure we dont leak
496 	 * a norefcounted dst
497 	 */
498 	skb_dst_force(skb);
499 
500 	spin_lock_irqsave(&list->lock, flags);
501 	sock_skb_set_dropcount(sk, skb);
502 	__skb_queue_tail(list, skb);
503 	spin_unlock_irqrestore(&list->lock, flags);
504 
505 	if (!sock_flag(sk, SOCK_DEAD))
506 		sk->sk_data_ready(sk);
507 	return 0;
508 }
509 EXPORT_SYMBOL(__sock_queue_rcv_skb);
510 
511 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
512 			      enum skb_drop_reason *reason)
513 {
514 	enum skb_drop_reason drop_reason;
515 	int err;
516 
517 	err = sk_filter(sk, skb);
518 	if (err) {
519 		drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
520 		goto out;
521 	}
522 	err = __sock_queue_rcv_skb(sk, skb);
523 	switch (err) {
524 	case -ENOMEM:
525 		drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
526 		break;
527 	case -ENOBUFS:
528 		drop_reason = SKB_DROP_REASON_PROTO_MEM;
529 		break;
530 	default:
531 		drop_reason = SKB_NOT_DROPPED_YET;
532 		break;
533 	}
534 out:
535 	if (reason)
536 		*reason = drop_reason;
537 	return err;
538 }
539 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
540 
541 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
542 		     const int nested, unsigned int trim_cap, bool refcounted)
543 {
544 	int rc = NET_RX_SUCCESS;
545 
546 	if (sk_filter_trim_cap(sk, skb, trim_cap))
547 		goto discard_and_relse;
548 
549 	skb->dev = NULL;
550 
551 	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
552 		atomic_inc(&sk->sk_drops);
553 		goto discard_and_relse;
554 	}
555 	if (nested)
556 		bh_lock_sock_nested(sk);
557 	else
558 		bh_lock_sock(sk);
559 	if (!sock_owned_by_user(sk)) {
560 		/*
561 		 * trylock + unlock semantics:
562 		 */
563 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
564 
565 		rc = sk_backlog_rcv(sk, skb);
566 
567 		mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
568 	} else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
569 		bh_unlock_sock(sk);
570 		atomic_inc(&sk->sk_drops);
571 		goto discard_and_relse;
572 	}
573 
574 	bh_unlock_sock(sk);
575 out:
576 	if (refcounted)
577 		sock_put(sk);
578 	return rc;
579 discard_and_relse:
580 	kfree_skb(skb);
581 	goto out;
582 }
583 EXPORT_SYMBOL(__sk_receive_skb);
584 
585 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
586 							  u32));
587 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
588 							   u32));
589 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
590 {
591 	struct dst_entry *dst = __sk_dst_get(sk);
592 
593 	if (dst && dst->obsolete &&
594 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
595 			       dst, cookie) == NULL) {
596 		sk_tx_queue_clear(sk);
597 		sk->sk_dst_pending_confirm = 0;
598 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
599 		dst_release(dst);
600 		return NULL;
601 	}
602 
603 	return dst;
604 }
605 EXPORT_SYMBOL(__sk_dst_check);
606 
607 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
608 {
609 	struct dst_entry *dst = sk_dst_get(sk);
610 
611 	if (dst && dst->obsolete &&
612 	    INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
613 			       dst, cookie) == NULL) {
614 		sk_dst_reset(sk);
615 		dst_release(dst);
616 		return NULL;
617 	}
618 
619 	return dst;
620 }
621 EXPORT_SYMBOL(sk_dst_check);
622 
623 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
624 {
625 	int ret = -ENOPROTOOPT;
626 #ifdef CONFIG_NETDEVICES
627 	struct net *net = sock_net(sk);
628 
629 	/* Sorry... */
630 	ret = -EPERM;
631 	if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
632 		goto out;
633 
634 	ret = -EINVAL;
635 	if (ifindex < 0)
636 		goto out;
637 
638 	/* Paired with all READ_ONCE() done locklessly. */
639 	WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
640 
641 	if (sk->sk_prot->rehash)
642 		sk->sk_prot->rehash(sk);
643 	sk_dst_reset(sk);
644 
645 	ret = 0;
646 
647 out:
648 #endif
649 
650 	return ret;
651 }
652 
653 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
654 {
655 	int ret;
656 
657 	if (lock_sk)
658 		lock_sock(sk);
659 	ret = sock_bindtoindex_locked(sk, ifindex);
660 	if (lock_sk)
661 		release_sock(sk);
662 
663 	return ret;
664 }
665 EXPORT_SYMBOL(sock_bindtoindex);
666 
667 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
668 {
669 	int ret = -ENOPROTOOPT;
670 #ifdef CONFIG_NETDEVICES
671 	struct net *net = sock_net(sk);
672 	char devname[IFNAMSIZ];
673 	int index;
674 
675 	ret = -EINVAL;
676 	if (optlen < 0)
677 		goto out;
678 
679 	/* Bind this socket to a particular device like "eth0",
680 	 * as specified in the passed interface name. If the
681 	 * name is "" or the option length is zero the socket
682 	 * is not bound.
683 	 */
684 	if (optlen > IFNAMSIZ - 1)
685 		optlen = IFNAMSIZ - 1;
686 	memset(devname, 0, sizeof(devname));
687 
688 	ret = -EFAULT;
689 	if (copy_from_sockptr(devname, optval, optlen))
690 		goto out;
691 
692 	index = 0;
693 	if (devname[0] != '\0') {
694 		struct net_device *dev;
695 
696 		rcu_read_lock();
697 		dev = dev_get_by_name_rcu(net, devname);
698 		if (dev)
699 			index = dev->ifindex;
700 		rcu_read_unlock();
701 		ret = -ENODEV;
702 		if (!dev)
703 			goto out;
704 	}
705 
706 	sockopt_lock_sock(sk);
707 	ret = sock_bindtoindex_locked(sk, index);
708 	sockopt_release_sock(sk);
709 out:
710 #endif
711 
712 	return ret;
713 }
714 
715 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
716 				sockptr_t optlen, int len)
717 {
718 	int ret = -ENOPROTOOPT;
719 #ifdef CONFIG_NETDEVICES
720 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
721 	struct net *net = sock_net(sk);
722 	char devname[IFNAMSIZ];
723 
724 	if (bound_dev_if == 0) {
725 		len = 0;
726 		goto zero;
727 	}
728 
729 	ret = -EINVAL;
730 	if (len < IFNAMSIZ)
731 		goto out;
732 
733 	ret = netdev_get_name(net, devname, bound_dev_if);
734 	if (ret)
735 		goto out;
736 
737 	len = strlen(devname) + 1;
738 
739 	ret = -EFAULT;
740 	if (copy_to_sockptr(optval, devname, len))
741 		goto out;
742 
743 zero:
744 	ret = -EFAULT;
745 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
746 		goto out;
747 
748 	ret = 0;
749 
750 out:
751 #endif
752 
753 	return ret;
754 }
755 
756 bool sk_mc_loop(struct sock *sk)
757 {
758 	if (dev_recursion_level())
759 		return false;
760 	if (!sk)
761 		return true;
762 	switch (sk->sk_family) {
763 	case AF_INET:
764 		return inet_sk(sk)->mc_loop;
765 #if IS_ENABLED(CONFIG_IPV6)
766 	case AF_INET6:
767 		return inet6_sk(sk)->mc_loop;
768 #endif
769 	}
770 	WARN_ON_ONCE(1);
771 	return true;
772 }
773 EXPORT_SYMBOL(sk_mc_loop);
774 
775 void sock_set_reuseaddr(struct sock *sk)
776 {
777 	lock_sock(sk);
778 	sk->sk_reuse = SK_CAN_REUSE;
779 	release_sock(sk);
780 }
781 EXPORT_SYMBOL(sock_set_reuseaddr);
782 
783 void sock_set_reuseport(struct sock *sk)
784 {
785 	lock_sock(sk);
786 	sk->sk_reuseport = true;
787 	release_sock(sk);
788 }
789 EXPORT_SYMBOL(sock_set_reuseport);
790 
791 void sock_no_linger(struct sock *sk)
792 {
793 	lock_sock(sk);
794 	sk->sk_lingertime = 0;
795 	sock_set_flag(sk, SOCK_LINGER);
796 	release_sock(sk);
797 }
798 EXPORT_SYMBOL(sock_no_linger);
799 
800 void sock_set_priority(struct sock *sk, u32 priority)
801 {
802 	lock_sock(sk);
803 	sk->sk_priority = priority;
804 	release_sock(sk);
805 }
806 EXPORT_SYMBOL(sock_set_priority);
807 
808 void sock_set_sndtimeo(struct sock *sk, s64 secs)
809 {
810 	lock_sock(sk);
811 	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
812 		sk->sk_sndtimeo = secs * HZ;
813 	else
814 		sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
815 	release_sock(sk);
816 }
817 EXPORT_SYMBOL(sock_set_sndtimeo);
818 
819 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
820 {
821 	if (val)  {
822 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
823 		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
824 		sock_set_flag(sk, SOCK_RCVTSTAMP);
825 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
826 	} else {
827 		sock_reset_flag(sk, SOCK_RCVTSTAMP);
828 		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
829 	}
830 }
831 
832 void sock_enable_timestamps(struct sock *sk)
833 {
834 	lock_sock(sk);
835 	__sock_set_timestamps(sk, true, false, true);
836 	release_sock(sk);
837 }
838 EXPORT_SYMBOL(sock_enable_timestamps);
839 
840 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
841 {
842 	switch (optname) {
843 	case SO_TIMESTAMP_OLD:
844 		__sock_set_timestamps(sk, valbool, false, false);
845 		break;
846 	case SO_TIMESTAMP_NEW:
847 		__sock_set_timestamps(sk, valbool, true, false);
848 		break;
849 	case SO_TIMESTAMPNS_OLD:
850 		__sock_set_timestamps(sk, valbool, false, true);
851 		break;
852 	case SO_TIMESTAMPNS_NEW:
853 		__sock_set_timestamps(sk, valbool, true, true);
854 		break;
855 	}
856 }
857 
858 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
859 {
860 	struct net *net = sock_net(sk);
861 	struct net_device *dev = NULL;
862 	bool match = false;
863 	int *vclock_index;
864 	int i, num;
865 
866 	if (sk->sk_bound_dev_if)
867 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
868 
869 	if (!dev) {
870 		pr_err("%s: sock not bind to device\n", __func__);
871 		return -EOPNOTSUPP;
872 	}
873 
874 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
875 	dev_put(dev);
876 
877 	for (i = 0; i < num; i++) {
878 		if (*(vclock_index + i) == phc_index) {
879 			match = true;
880 			break;
881 		}
882 	}
883 
884 	if (num > 0)
885 		kfree(vclock_index);
886 
887 	if (!match)
888 		return -EINVAL;
889 
890 	sk->sk_bind_phc = phc_index;
891 
892 	return 0;
893 }
894 
895 int sock_set_timestamping(struct sock *sk, int optname,
896 			  struct so_timestamping timestamping)
897 {
898 	int val = timestamping.flags;
899 	int ret;
900 
901 	if (val & ~SOF_TIMESTAMPING_MASK)
902 		return -EINVAL;
903 
904 	if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
905 	    !(val & SOF_TIMESTAMPING_OPT_ID))
906 		return -EINVAL;
907 
908 	if (val & SOF_TIMESTAMPING_OPT_ID &&
909 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
910 		if (sk_is_tcp(sk)) {
911 			if ((1 << sk->sk_state) &
912 			    (TCPF_CLOSE | TCPF_LISTEN))
913 				return -EINVAL;
914 			if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
915 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
916 			else
917 				atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
918 		} else {
919 			atomic_set(&sk->sk_tskey, 0);
920 		}
921 	}
922 
923 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
924 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
925 		return -EINVAL;
926 
927 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
928 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
929 		if (ret)
930 			return ret;
931 	}
932 
933 	sk->sk_tsflags = val;
934 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
935 
936 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
937 		sock_enable_timestamp(sk,
938 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
939 	else
940 		sock_disable_timestamp(sk,
941 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
942 	return 0;
943 }
944 
945 void sock_set_keepalive(struct sock *sk)
946 {
947 	lock_sock(sk);
948 	if (sk->sk_prot->keepalive)
949 		sk->sk_prot->keepalive(sk, true);
950 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
951 	release_sock(sk);
952 }
953 EXPORT_SYMBOL(sock_set_keepalive);
954 
955 static void __sock_set_rcvbuf(struct sock *sk, int val)
956 {
957 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
958 	 * as a negative value.
959 	 */
960 	val = min_t(int, val, INT_MAX / 2);
961 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
962 
963 	/* We double it on the way in to account for "struct sk_buff" etc.
964 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
965 	 * will allow that much actual data to be received on that socket.
966 	 *
967 	 * Applications are unaware that "struct sk_buff" and other overheads
968 	 * allocate from the receive buffer during socket buffer allocation.
969 	 *
970 	 * And after considering the possible alternatives, returning the value
971 	 * we actually used in getsockopt is the most desirable behavior.
972 	 */
973 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
974 }
975 
976 void sock_set_rcvbuf(struct sock *sk, int val)
977 {
978 	lock_sock(sk);
979 	__sock_set_rcvbuf(sk, val);
980 	release_sock(sk);
981 }
982 EXPORT_SYMBOL(sock_set_rcvbuf);
983 
984 static void __sock_set_mark(struct sock *sk, u32 val)
985 {
986 	if (val != sk->sk_mark) {
987 		sk->sk_mark = val;
988 		sk_dst_reset(sk);
989 	}
990 }
991 
992 void sock_set_mark(struct sock *sk, u32 val)
993 {
994 	lock_sock(sk);
995 	__sock_set_mark(sk, val);
996 	release_sock(sk);
997 }
998 EXPORT_SYMBOL(sock_set_mark);
999 
1000 static void sock_release_reserved_memory(struct sock *sk, int bytes)
1001 {
1002 	/* Round down bytes to multiple of pages */
1003 	bytes = round_down(bytes, PAGE_SIZE);
1004 
1005 	WARN_ON(bytes > sk->sk_reserved_mem);
1006 	sk->sk_reserved_mem -= bytes;
1007 	sk_mem_reclaim(sk);
1008 }
1009 
1010 static int sock_reserve_memory(struct sock *sk, int bytes)
1011 {
1012 	long allocated;
1013 	bool charged;
1014 	int pages;
1015 
1016 	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1017 		return -EOPNOTSUPP;
1018 
1019 	if (!bytes)
1020 		return 0;
1021 
1022 	pages = sk_mem_pages(bytes);
1023 
1024 	/* pre-charge to memcg */
1025 	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1026 					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1027 	if (!charged)
1028 		return -ENOMEM;
1029 
1030 	/* pre-charge to forward_alloc */
1031 	sk_memory_allocated_add(sk, pages);
1032 	allocated = sk_memory_allocated(sk);
1033 	/* If the system goes into memory pressure with this
1034 	 * precharge, give up and return error.
1035 	 */
1036 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1037 		sk_memory_allocated_sub(sk, pages);
1038 		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1039 		return -ENOMEM;
1040 	}
1041 	sk->sk_forward_alloc += pages << PAGE_SHIFT;
1042 
1043 	sk->sk_reserved_mem += pages << PAGE_SHIFT;
1044 
1045 	return 0;
1046 }
1047 
1048 void sockopt_lock_sock(struct sock *sk)
1049 {
1050 	/* When current->bpf_ctx is set, the setsockopt is called from
1051 	 * a bpf prog.  bpf has ensured the sk lock has been
1052 	 * acquired before calling setsockopt().
1053 	 */
1054 	if (has_current_bpf_ctx())
1055 		return;
1056 
1057 	lock_sock(sk);
1058 }
1059 EXPORT_SYMBOL(sockopt_lock_sock);
1060 
1061 void sockopt_release_sock(struct sock *sk)
1062 {
1063 	if (has_current_bpf_ctx())
1064 		return;
1065 
1066 	release_sock(sk);
1067 }
1068 EXPORT_SYMBOL(sockopt_release_sock);
1069 
1070 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1071 {
1072 	return has_current_bpf_ctx() || ns_capable(ns, cap);
1073 }
1074 EXPORT_SYMBOL(sockopt_ns_capable);
1075 
1076 bool sockopt_capable(int cap)
1077 {
1078 	return has_current_bpf_ctx() || capable(cap);
1079 }
1080 EXPORT_SYMBOL(sockopt_capable);
1081 
1082 /*
1083  *	This is meant for all protocols to use and covers goings on
1084  *	at the socket level. Everything here is generic.
1085  */
1086 
1087 int sk_setsockopt(struct sock *sk, int level, int optname,
1088 		  sockptr_t optval, unsigned int optlen)
1089 {
1090 	struct so_timestamping timestamping;
1091 	struct socket *sock = sk->sk_socket;
1092 	struct sock_txtime sk_txtime;
1093 	int val;
1094 	int valbool;
1095 	struct linger ling;
1096 	int ret = 0;
1097 
1098 	/*
1099 	 *	Options without arguments
1100 	 */
1101 
1102 	if (optname == SO_BINDTODEVICE)
1103 		return sock_setbindtodevice(sk, optval, optlen);
1104 
1105 	if (optlen < sizeof(int))
1106 		return -EINVAL;
1107 
1108 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1109 		return -EFAULT;
1110 
1111 	valbool = val ? 1 : 0;
1112 
1113 	sockopt_lock_sock(sk);
1114 
1115 	switch (optname) {
1116 	case SO_DEBUG:
1117 		if (val && !sockopt_capable(CAP_NET_ADMIN))
1118 			ret = -EACCES;
1119 		else
1120 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1121 		break;
1122 	case SO_REUSEADDR:
1123 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1124 		break;
1125 	case SO_REUSEPORT:
1126 		sk->sk_reuseport = valbool;
1127 		break;
1128 	case SO_TYPE:
1129 	case SO_PROTOCOL:
1130 	case SO_DOMAIN:
1131 	case SO_ERROR:
1132 		ret = -ENOPROTOOPT;
1133 		break;
1134 	case SO_DONTROUTE:
1135 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1136 		sk_dst_reset(sk);
1137 		break;
1138 	case SO_BROADCAST:
1139 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1140 		break;
1141 	case SO_SNDBUF:
1142 		/* Don't error on this BSD doesn't and if you think
1143 		 * about it this is right. Otherwise apps have to
1144 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1145 		 * are treated in BSD as hints
1146 		 */
1147 		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1148 set_sndbuf:
1149 		/* Ensure val * 2 fits into an int, to prevent max_t()
1150 		 * from treating it as a negative value.
1151 		 */
1152 		val = min_t(int, val, INT_MAX / 2);
1153 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1154 		WRITE_ONCE(sk->sk_sndbuf,
1155 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1156 		/* Wake up sending tasks if we upped the value. */
1157 		sk->sk_write_space(sk);
1158 		break;
1159 
1160 	case SO_SNDBUFFORCE:
1161 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1162 			ret = -EPERM;
1163 			break;
1164 		}
1165 
1166 		/* No negative values (to prevent underflow, as val will be
1167 		 * multiplied by 2).
1168 		 */
1169 		if (val < 0)
1170 			val = 0;
1171 		goto set_sndbuf;
1172 
1173 	case SO_RCVBUF:
1174 		/* Don't error on this BSD doesn't and if you think
1175 		 * about it this is right. Otherwise apps have to
1176 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1177 		 * are treated in BSD as hints
1178 		 */
1179 		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1180 		break;
1181 
1182 	case SO_RCVBUFFORCE:
1183 		if (!sockopt_capable(CAP_NET_ADMIN)) {
1184 			ret = -EPERM;
1185 			break;
1186 		}
1187 
1188 		/* No negative values (to prevent underflow, as val will be
1189 		 * multiplied by 2).
1190 		 */
1191 		__sock_set_rcvbuf(sk, max(val, 0));
1192 		break;
1193 
1194 	case SO_KEEPALIVE:
1195 		if (sk->sk_prot->keepalive)
1196 			sk->sk_prot->keepalive(sk, valbool);
1197 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1198 		break;
1199 
1200 	case SO_OOBINLINE:
1201 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1202 		break;
1203 
1204 	case SO_NO_CHECK:
1205 		sk->sk_no_check_tx = valbool;
1206 		break;
1207 
1208 	case SO_PRIORITY:
1209 		if ((val >= 0 && val <= 6) ||
1210 		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1211 		    sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1212 			sk->sk_priority = val;
1213 		else
1214 			ret = -EPERM;
1215 		break;
1216 
1217 	case SO_LINGER:
1218 		if (optlen < sizeof(ling)) {
1219 			ret = -EINVAL;	/* 1003.1g */
1220 			break;
1221 		}
1222 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1223 			ret = -EFAULT;
1224 			break;
1225 		}
1226 		if (!ling.l_onoff)
1227 			sock_reset_flag(sk, SOCK_LINGER);
1228 		else {
1229 #if (BITS_PER_LONG == 32)
1230 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
1231 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
1232 			else
1233 #endif
1234 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
1235 			sock_set_flag(sk, SOCK_LINGER);
1236 		}
1237 		break;
1238 
1239 	case SO_BSDCOMPAT:
1240 		break;
1241 
1242 	case SO_PASSCRED:
1243 		if (valbool)
1244 			set_bit(SOCK_PASSCRED, &sock->flags);
1245 		else
1246 			clear_bit(SOCK_PASSCRED, &sock->flags);
1247 		break;
1248 
1249 	case SO_TIMESTAMP_OLD:
1250 	case SO_TIMESTAMP_NEW:
1251 	case SO_TIMESTAMPNS_OLD:
1252 	case SO_TIMESTAMPNS_NEW:
1253 		sock_set_timestamp(sk, optname, valbool);
1254 		break;
1255 
1256 	case SO_TIMESTAMPING_NEW:
1257 	case SO_TIMESTAMPING_OLD:
1258 		if (optlen == sizeof(timestamping)) {
1259 			if (copy_from_sockptr(&timestamping, optval,
1260 					      sizeof(timestamping))) {
1261 				ret = -EFAULT;
1262 				break;
1263 			}
1264 		} else {
1265 			memset(&timestamping, 0, sizeof(timestamping));
1266 			timestamping.flags = val;
1267 		}
1268 		ret = sock_set_timestamping(sk, optname, timestamping);
1269 		break;
1270 
1271 	case SO_RCVLOWAT:
1272 		if (val < 0)
1273 			val = INT_MAX;
1274 		if (sock && sock->ops->set_rcvlowat)
1275 			ret = sock->ops->set_rcvlowat(sk, val);
1276 		else
1277 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1278 		break;
1279 
1280 	case SO_RCVTIMEO_OLD:
1281 	case SO_RCVTIMEO_NEW:
1282 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1283 				       optlen, optname == SO_RCVTIMEO_OLD);
1284 		break;
1285 
1286 	case SO_SNDTIMEO_OLD:
1287 	case SO_SNDTIMEO_NEW:
1288 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1289 				       optlen, optname == SO_SNDTIMEO_OLD);
1290 		break;
1291 
1292 	case SO_ATTACH_FILTER: {
1293 		struct sock_fprog fprog;
1294 
1295 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1296 		if (!ret)
1297 			ret = sk_attach_filter(&fprog, sk);
1298 		break;
1299 	}
1300 	case SO_ATTACH_BPF:
1301 		ret = -EINVAL;
1302 		if (optlen == sizeof(u32)) {
1303 			u32 ufd;
1304 
1305 			ret = -EFAULT;
1306 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1307 				break;
1308 
1309 			ret = sk_attach_bpf(ufd, sk);
1310 		}
1311 		break;
1312 
1313 	case SO_ATTACH_REUSEPORT_CBPF: {
1314 		struct sock_fprog fprog;
1315 
1316 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1317 		if (!ret)
1318 			ret = sk_reuseport_attach_filter(&fprog, sk);
1319 		break;
1320 	}
1321 	case SO_ATTACH_REUSEPORT_EBPF:
1322 		ret = -EINVAL;
1323 		if (optlen == sizeof(u32)) {
1324 			u32 ufd;
1325 
1326 			ret = -EFAULT;
1327 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1328 				break;
1329 
1330 			ret = sk_reuseport_attach_bpf(ufd, sk);
1331 		}
1332 		break;
1333 
1334 	case SO_DETACH_REUSEPORT_BPF:
1335 		ret = reuseport_detach_prog(sk);
1336 		break;
1337 
1338 	case SO_DETACH_FILTER:
1339 		ret = sk_detach_filter(sk);
1340 		break;
1341 
1342 	case SO_LOCK_FILTER:
1343 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1344 			ret = -EPERM;
1345 		else
1346 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1347 		break;
1348 
1349 	case SO_PASSSEC:
1350 		if (valbool)
1351 			set_bit(SOCK_PASSSEC, &sock->flags);
1352 		else
1353 			clear_bit(SOCK_PASSSEC, &sock->flags);
1354 		break;
1355 	case SO_MARK:
1356 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1357 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1358 			ret = -EPERM;
1359 			break;
1360 		}
1361 
1362 		__sock_set_mark(sk, val);
1363 		break;
1364 	case SO_RCVMARK:
1365 		if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1366 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1367 			ret = -EPERM;
1368 			break;
1369 		}
1370 
1371 		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1372 		break;
1373 
1374 	case SO_RXQ_OVFL:
1375 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1376 		break;
1377 
1378 	case SO_WIFI_STATUS:
1379 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1380 		break;
1381 
1382 	case SO_PEEK_OFF:
1383 		if (sock->ops->set_peek_off)
1384 			ret = sock->ops->set_peek_off(sk, val);
1385 		else
1386 			ret = -EOPNOTSUPP;
1387 		break;
1388 
1389 	case SO_NOFCS:
1390 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1391 		break;
1392 
1393 	case SO_SELECT_ERR_QUEUE:
1394 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1395 		break;
1396 
1397 #ifdef CONFIG_NET_RX_BUSY_POLL
1398 	case SO_BUSY_POLL:
1399 		/* allow unprivileged users to decrease the value */
1400 		if ((val > sk->sk_ll_usec) && !sockopt_capable(CAP_NET_ADMIN))
1401 			ret = -EPERM;
1402 		else {
1403 			if (val < 0)
1404 				ret = -EINVAL;
1405 			else
1406 				WRITE_ONCE(sk->sk_ll_usec, val);
1407 		}
1408 		break;
1409 	case SO_PREFER_BUSY_POLL:
1410 		if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1411 			ret = -EPERM;
1412 		else
1413 			WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1414 		break;
1415 	case SO_BUSY_POLL_BUDGET:
1416 		if (val > READ_ONCE(sk->sk_busy_poll_budget) && !sockopt_capable(CAP_NET_ADMIN)) {
1417 			ret = -EPERM;
1418 		} else {
1419 			if (val < 0 || val > U16_MAX)
1420 				ret = -EINVAL;
1421 			else
1422 				WRITE_ONCE(sk->sk_busy_poll_budget, val);
1423 		}
1424 		break;
1425 #endif
1426 
1427 	case SO_MAX_PACING_RATE:
1428 		{
1429 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1430 
1431 		if (sizeof(ulval) != sizeof(val) &&
1432 		    optlen >= sizeof(ulval) &&
1433 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1434 			ret = -EFAULT;
1435 			break;
1436 		}
1437 		if (ulval != ~0UL)
1438 			cmpxchg(&sk->sk_pacing_status,
1439 				SK_PACING_NONE,
1440 				SK_PACING_NEEDED);
1441 		sk->sk_max_pacing_rate = ulval;
1442 		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1443 		break;
1444 		}
1445 	case SO_INCOMING_CPU:
1446 		reuseport_update_incoming_cpu(sk, val);
1447 		break;
1448 
1449 	case SO_CNX_ADVICE:
1450 		if (val == 1)
1451 			dst_negative_advice(sk);
1452 		break;
1453 
1454 	case SO_ZEROCOPY:
1455 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1456 			if (!(sk_is_tcp(sk) ||
1457 			      (sk->sk_type == SOCK_DGRAM &&
1458 			       sk->sk_protocol == IPPROTO_UDP)))
1459 				ret = -EOPNOTSUPP;
1460 		} else if (sk->sk_family != PF_RDS) {
1461 			ret = -EOPNOTSUPP;
1462 		}
1463 		if (!ret) {
1464 			if (val < 0 || val > 1)
1465 				ret = -EINVAL;
1466 			else
1467 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1468 		}
1469 		break;
1470 
1471 	case SO_TXTIME:
1472 		if (optlen != sizeof(struct sock_txtime)) {
1473 			ret = -EINVAL;
1474 			break;
1475 		} else if (copy_from_sockptr(&sk_txtime, optval,
1476 			   sizeof(struct sock_txtime))) {
1477 			ret = -EFAULT;
1478 			break;
1479 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1480 			ret = -EINVAL;
1481 			break;
1482 		}
1483 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1484 		 * scheduler has enough safe guards.
1485 		 */
1486 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1487 		    !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1488 			ret = -EPERM;
1489 			break;
1490 		}
1491 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1492 		sk->sk_clockid = sk_txtime.clockid;
1493 		sk->sk_txtime_deadline_mode =
1494 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1495 		sk->sk_txtime_report_errors =
1496 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1497 		break;
1498 
1499 	case SO_BINDTOIFINDEX:
1500 		ret = sock_bindtoindex_locked(sk, val);
1501 		break;
1502 
1503 	case SO_BUF_LOCK:
1504 		if (val & ~SOCK_BUF_LOCK_MASK) {
1505 			ret = -EINVAL;
1506 			break;
1507 		}
1508 		sk->sk_userlocks = val | (sk->sk_userlocks &
1509 					  ~SOCK_BUF_LOCK_MASK);
1510 		break;
1511 
1512 	case SO_RESERVE_MEM:
1513 	{
1514 		int delta;
1515 
1516 		if (val < 0) {
1517 			ret = -EINVAL;
1518 			break;
1519 		}
1520 
1521 		delta = val - sk->sk_reserved_mem;
1522 		if (delta < 0)
1523 			sock_release_reserved_memory(sk, -delta);
1524 		else
1525 			ret = sock_reserve_memory(sk, delta);
1526 		break;
1527 	}
1528 
1529 	case SO_TXREHASH:
1530 		if (val < -1 || val > 1) {
1531 			ret = -EINVAL;
1532 			break;
1533 		}
1534 		if ((u8)val == SOCK_TXREHASH_DEFAULT)
1535 			val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1536 		/* Paired with READ_ONCE() in tcp_rtx_synack() */
1537 		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1538 		break;
1539 
1540 	default:
1541 		ret = -ENOPROTOOPT;
1542 		break;
1543 	}
1544 	sockopt_release_sock(sk);
1545 	return ret;
1546 }
1547 
1548 int sock_setsockopt(struct socket *sock, int level, int optname,
1549 		    sockptr_t optval, unsigned int optlen)
1550 {
1551 	return sk_setsockopt(sock->sk, level, optname,
1552 			     optval, optlen);
1553 }
1554 EXPORT_SYMBOL(sock_setsockopt);
1555 
1556 static const struct cred *sk_get_peer_cred(struct sock *sk)
1557 {
1558 	const struct cred *cred;
1559 
1560 	spin_lock(&sk->sk_peer_lock);
1561 	cred = get_cred(sk->sk_peer_cred);
1562 	spin_unlock(&sk->sk_peer_lock);
1563 
1564 	return cred;
1565 }
1566 
1567 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1568 			  struct ucred *ucred)
1569 {
1570 	ucred->pid = pid_vnr(pid);
1571 	ucred->uid = ucred->gid = -1;
1572 	if (cred) {
1573 		struct user_namespace *current_ns = current_user_ns();
1574 
1575 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1576 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1577 	}
1578 }
1579 
1580 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1581 {
1582 	struct user_namespace *user_ns = current_user_ns();
1583 	int i;
1584 
1585 	for (i = 0; i < src->ngroups; i++) {
1586 		gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1587 
1588 		if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1589 			return -EFAULT;
1590 	}
1591 
1592 	return 0;
1593 }
1594 
1595 int sk_getsockopt(struct sock *sk, int level, int optname,
1596 		  sockptr_t optval, sockptr_t optlen)
1597 {
1598 	struct socket *sock = sk->sk_socket;
1599 
1600 	union {
1601 		int val;
1602 		u64 val64;
1603 		unsigned long ulval;
1604 		struct linger ling;
1605 		struct old_timeval32 tm32;
1606 		struct __kernel_old_timeval tm;
1607 		struct  __kernel_sock_timeval stm;
1608 		struct sock_txtime txtime;
1609 		struct so_timestamping timestamping;
1610 	} v;
1611 
1612 	int lv = sizeof(int);
1613 	int len;
1614 
1615 	if (copy_from_sockptr(&len, optlen, sizeof(int)))
1616 		return -EFAULT;
1617 	if (len < 0)
1618 		return -EINVAL;
1619 
1620 	memset(&v, 0, sizeof(v));
1621 
1622 	switch (optname) {
1623 	case SO_DEBUG:
1624 		v.val = sock_flag(sk, SOCK_DBG);
1625 		break;
1626 
1627 	case SO_DONTROUTE:
1628 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1629 		break;
1630 
1631 	case SO_BROADCAST:
1632 		v.val = sock_flag(sk, SOCK_BROADCAST);
1633 		break;
1634 
1635 	case SO_SNDBUF:
1636 		v.val = sk->sk_sndbuf;
1637 		break;
1638 
1639 	case SO_RCVBUF:
1640 		v.val = sk->sk_rcvbuf;
1641 		break;
1642 
1643 	case SO_REUSEADDR:
1644 		v.val = sk->sk_reuse;
1645 		break;
1646 
1647 	case SO_REUSEPORT:
1648 		v.val = sk->sk_reuseport;
1649 		break;
1650 
1651 	case SO_KEEPALIVE:
1652 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1653 		break;
1654 
1655 	case SO_TYPE:
1656 		v.val = sk->sk_type;
1657 		break;
1658 
1659 	case SO_PROTOCOL:
1660 		v.val = sk->sk_protocol;
1661 		break;
1662 
1663 	case SO_DOMAIN:
1664 		v.val = sk->sk_family;
1665 		break;
1666 
1667 	case SO_ERROR:
1668 		v.val = -sock_error(sk);
1669 		if (v.val == 0)
1670 			v.val = xchg(&sk->sk_err_soft, 0);
1671 		break;
1672 
1673 	case SO_OOBINLINE:
1674 		v.val = sock_flag(sk, SOCK_URGINLINE);
1675 		break;
1676 
1677 	case SO_NO_CHECK:
1678 		v.val = sk->sk_no_check_tx;
1679 		break;
1680 
1681 	case SO_PRIORITY:
1682 		v.val = sk->sk_priority;
1683 		break;
1684 
1685 	case SO_LINGER:
1686 		lv		= sizeof(v.ling);
1687 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1688 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1689 		break;
1690 
1691 	case SO_BSDCOMPAT:
1692 		break;
1693 
1694 	case SO_TIMESTAMP_OLD:
1695 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1696 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1697 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1698 		break;
1699 
1700 	case SO_TIMESTAMPNS_OLD:
1701 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1702 		break;
1703 
1704 	case SO_TIMESTAMP_NEW:
1705 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1706 		break;
1707 
1708 	case SO_TIMESTAMPNS_NEW:
1709 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1710 		break;
1711 
1712 	case SO_TIMESTAMPING_OLD:
1713 		lv = sizeof(v.timestamping);
1714 		v.timestamping.flags = sk->sk_tsflags;
1715 		v.timestamping.bind_phc = sk->sk_bind_phc;
1716 		break;
1717 
1718 	case SO_RCVTIMEO_OLD:
1719 	case SO_RCVTIMEO_NEW:
1720 		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1721 		break;
1722 
1723 	case SO_SNDTIMEO_OLD:
1724 	case SO_SNDTIMEO_NEW:
1725 		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1726 		break;
1727 
1728 	case SO_RCVLOWAT:
1729 		v.val = sk->sk_rcvlowat;
1730 		break;
1731 
1732 	case SO_SNDLOWAT:
1733 		v.val = 1;
1734 		break;
1735 
1736 	case SO_PASSCRED:
1737 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1738 		break;
1739 
1740 	case SO_PEERCRED:
1741 	{
1742 		struct ucred peercred;
1743 		if (len > sizeof(peercred))
1744 			len = sizeof(peercred);
1745 
1746 		spin_lock(&sk->sk_peer_lock);
1747 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1748 		spin_unlock(&sk->sk_peer_lock);
1749 
1750 		if (copy_to_sockptr(optval, &peercred, len))
1751 			return -EFAULT;
1752 		goto lenout;
1753 	}
1754 
1755 	case SO_PEERGROUPS:
1756 	{
1757 		const struct cred *cred;
1758 		int ret, n;
1759 
1760 		cred = sk_get_peer_cred(sk);
1761 		if (!cred)
1762 			return -ENODATA;
1763 
1764 		n = cred->group_info->ngroups;
1765 		if (len < n * sizeof(gid_t)) {
1766 			len = n * sizeof(gid_t);
1767 			put_cred(cred);
1768 			return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1769 		}
1770 		len = n * sizeof(gid_t);
1771 
1772 		ret = groups_to_user(optval, cred->group_info);
1773 		put_cred(cred);
1774 		if (ret)
1775 			return ret;
1776 		goto lenout;
1777 	}
1778 
1779 	case SO_PEERNAME:
1780 	{
1781 		char address[128];
1782 
1783 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1784 		if (lv < 0)
1785 			return -ENOTCONN;
1786 		if (lv < len)
1787 			return -EINVAL;
1788 		if (copy_to_sockptr(optval, address, len))
1789 			return -EFAULT;
1790 		goto lenout;
1791 	}
1792 
1793 	/* Dubious BSD thing... Probably nobody even uses it, but
1794 	 * the UNIX standard wants it for whatever reason... -DaveM
1795 	 */
1796 	case SO_ACCEPTCONN:
1797 		v.val = sk->sk_state == TCP_LISTEN;
1798 		break;
1799 
1800 	case SO_PASSSEC:
1801 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1802 		break;
1803 
1804 	case SO_PEERSEC:
1805 		return security_socket_getpeersec_stream(sock,
1806 							 optval, optlen, len);
1807 
1808 	case SO_MARK:
1809 		v.val = sk->sk_mark;
1810 		break;
1811 
1812 	case SO_RCVMARK:
1813 		v.val = sock_flag(sk, SOCK_RCVMARK);
1814 		break;
1815 
1816 	case SO_RXQ_OVFL:
1817 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1818 		break;
1819 
1820 	case SO_WIFI_STATUS:
1821 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1822 		break;
1823 
1824 	case SO_PEEK_OFF:
1825 		if (!sock->ops->set_peek_off)
1826 			return -EOPNOTSUPP;
1827 
1828 		v.val = sk->sk_peek_off;
1829 		break;
1830 	case SO_NOFCS:
1831 		v.val = sock_flag(sk, SOCK_NOFCS);
1832 		break;
1833 
1834 	case SO_BINDTODEVICE:
1835 		return sock_getbindtodevice(sk, optval, optlen, len);
1836 
1837 	case SO_GET_FILTER:
1838 		len = sk_get_filter(sk, optval, len);
1839 		if (len < 0)
1840 			return len;
1841 
1842 		goto lenout;
1843 
1844 	case SO_LOCK_FILTER:
1845 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1846 		break;
1847 
1848 	case SO_BPF_EXTENSIONS:
1849 		v.val = bpf_tell_extensions();
1850 		break;
1851 
1852 	case SO_SELECT_ERR_QUEUE:
1853 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1854 		break;
1855 
1856 #ifdef CONFIG_NET_RX_BUSY_POLL
1857 	case SO_BUSY_POLL:
1858 		v.val = sk->sk_ll_usec;
1859 		break;
1860 	case SO_PREFER_BUSY_POLL:
1861 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1862 		break;
1863 #endif
1864 
1865 	case SO_MAX_PACING_RATE:
1866 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1867 			lv = sizeof(v.ulval);
1868 			v.ulval = sk->sk_max_pacing_rate;
1869 		} else {
1870 			/* 32bit version */
1871 			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1872 		}
1873 		break;
1874 
1875 	case SO_INCOMING_CPU:
1876 		v.val = READ_ONCE(sk->sk_incoming_cpu);
1877 		break;
1878 
1879 	case SO_MEMINFO:
1880 	{
1881 		u32 meminfo[SK_MEMINFO_VARS];
1882 
1883 		sk_get_meminfo(sk, meminfo);
1884 
1885 		len = min_t(unsigned int, len, sizeof(meminfo));
1886 		if (copy_to_sockptr(optval, &meminfo, len))
1887 			return -EFAULT;
1888 
1889 		goto lenout;
1890 	}
1891 
1892 #ifdef CONFIG_NET_RX_BUSY_POLL
1893 	case SO_INCOMING_NAPI_ID:
1894 		v.val = READ_ONCE(sk->sk_napi_id);
1895 
1896 		/* aggregate non-NAPI IDs down to 0 */
1897 		if (v.val < MIN_NAPI_ID)
1898 			v.val = 0;
1899 
1900 		break;
1901 #endif
1902 
1903 	case SO_COOKIE:
1904 		lv = sizeof(u64);
1905 		if (len < lv)
1906 			return -EINVAL;
1907 		v.val64 = sock_gen_cookie(sk);
1908 		break;
1909 
1910 	case SO_ZEROCOPY:
1911 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1912 		break;
1913 
1914 	case SO_TXTIME:
1915 		lv = sizeof(v.txtime);
1916 		v.txtime.clockid = sk->sk_clockid;
1917 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1918 				  SOF_TXTIME_DEADLINE_MODE : 0;
1919 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1920 				  SOF_TXTIME_REPORT_ERRORS : 0;
1921 		break;
1922 
1923 	case SO_BINDTOIFINDEX:
1924 		v.val = READ_ONCE(sk->sk_bound_dev_if);
1925 		break;
1926 
1927 	case SO_NETNS_COOKIE:
1928 		lv = sizeof(u64);
1929 		if (len != lv)
1930 			return -EINVAL;
1931 		v.val64 = sock_net(sk)->net_cookie;
1932 		break;
1933 
1934 	case SO_BUF_LOCK:
1935 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1936 		break;
1937 
1938 	case SO_RESERVE_MEM:
1939 		v.val = sk->sk_reserved_mem;
1940 		break;
1941 
1942 	case SO_TXREHASH:
1943 		v.val = sk->sk_txrehash;
1944 		break;
1945 
1946 	default:
1947 		/* We implement the SO_SNDLOWAT etc to not be settable
1948 		 * (1003.1g 7).
1949 		 */
1950 		return -ENOPROTOOPT;
1951 	}
1952 
1953 	if (len > lv)
1954 		len = lv;
1955 	if (copy_to_sockptr(optval, &v, len))
1956 		return -EFAULT;
1957 lenout:
1958 	if (copy_to_sockptr(optlen, &len, sizeof(int)))
1959 		return -EFAULT;
1960 	return 0;
1961 }
1962 
1963 int sock_getsockopt(struct socket *sock, int level, int optname,
1964 		    char __user *optval, int __user *optlen)
1965 {
1966 	return sk_getsockopt(sock->sk, level, optname,
1967 			     USER_SOCKPTR(optval),
1968 			     USER_SOCKPTR(optlen));
1969 }
1970 
1971 /*
1972  * Initialize an sk_lock.
1973  *
1974  * (We also register the sk_lock with the lock validator.)
1975  */
1976 static inline void sock_lock_init(struct sock *sk)
1977 {
1978 	if (sk->sk_kern_sock)
1979 		sock_lock_init_class_and_name(
1980 			sk,
1981 			af_family_kern_slock_key_strings[sk->sk_family],
1982 			af_family_kern_slock_keys + sk->sk_family,
1983 			af_family_kern_key_strings[sk->sk_family],
1984 			af_family_kern_keys + sk->sk_family);
1985 	else
1986 		sock_lock_init_class_and_name(
1987 			sk,
1988 			af_family_slock_key_strings[sk->sk_family],
1989 			af_family_slock_keys + sk->sk_family,
1990 			af_family_key_strings[sk->sk_family],
1991 			af_family_keys + sk->sk_family);
1992 }
1993 
1994 /*
1995  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1996  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1997  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1998  */
1999 static void sock_copy(struct sock *nsk, const struct sock *osk)
2000 {
2001 	const struct proto *prot = READ_ONCE(osk->sk_prot);
2002 #ifdef CONFIG_SECURITY_NETWORK
2003 	void *sptr = nsk->sk_security;
2004 #endif
2005 
2006 	/* If we move sk_tx_queue_mapping out of the private section,
2007 	 * we must check if sk_tx_queue_clear() is called after
2008 	 * sock_copy() in sk_clone_lock().
2009 	 */
2010 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2011 		     offsetof(struct sock, sk_dontcopy_begin) ||
2012 		     offsetof(struct sock, sk_tx_queue_mapping) >=
2013 		     offsetof(struct sock, sk_dontcopy_end));
2014 
2015 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2016 
2017 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2018 	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
2019 
2020 #ifdef CONFIG_SECURITY_NETWORK
2021 	nsk->sk_security = sptr;
2022 	security_sk_clone(osk, nsk);
2023 #endif
2024 }
2025 
2026 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2027 		int family)
2028 {
2029 	struct sock *sk;
2030 	struct kmem_cache *slab;
2031 
2032 	slab = prot->slab;
2033 	if (slab != NULL) {
2034 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2035 		if (!sk)
2036 			return sk;
2037 		if (want_init_on_alloc(priority))
2038 			sk_prot_clear_nulls(sk, prot->obj_size);
2039 	} else
2040 		sk = kmalloc(prot->obj_size, priority);
2041 
2042 	if (sk != NULL) {
2043 		if (security_sk_alloc(sk, family, priority))
2044 			goto out_free;
2045 
2046 		if (!try_module_get(prot->owner))
2047 			goto out_free_sec;
2048 	}
2049 
2050 	return sk;
2051 
2052 out_free_sec:
2053 	security_sk_free(sk);
2054 out_free:
2055 	if (slab != NULL)
2056 		kmem_cache_free(slab, sk);
2057 	else
2058 		kfree(sk);
2059 	return NULL;
2060 }
2061 
2062 static void sk_prot_free(struct proto *prot, struct sock *sk)
2063 {
2064 	struct kmem_cache *slab;
2065 	struct module *owner;
2066 
2067 	owner = prot->owner;
2068 	slab = prot->slab;
2069 
2070 	cgroup_sk_free(&sk->sk_cgrp_data);
2071 	mem_cgroup_sk_free(sk);
2072 	security_sk_free(sk);
2073 	if (slab != NULL)
2074 		kmem_cache_free(slab, sk);
2075 	else
2076 		kfree(sk);
2077 	module_put(owner);
2078 }
2079 
2080 /**
2081  *	sk_alloc - All socket objects are allocated here
2082  *	@net: the applicable net namespace
2083  *	@family: protocol family
2084  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2085  *	@prot: struct proto associated with this new sock instance
2086  *	@kern: is this to be a kernel socket?
2087  */
2088 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2089 		      struct proto *prot, int kern)
2090 {
2091 	struct sock *sk;
2092 
2093 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2094 	if (sk) {
2095 		sk->sk_family = family;
2096 		/*
2097 		 * See comment in struct sock definition to understand
2098 		 * why we need sk_prot_creator -acme
2099 		 */
2100 		sk->sk_prot = sk->sk_prot_creator = prot;
2101 		sk->sk_kern_sock = kern;
2102 		sock_lock_init(sk);
2103 		sk->sk_net_refcnt = kern ? 0 : 1;
2104 		if (likely(sk->sk_net_refcnt)) {
2105 			get_net_track(net, &sk->ns_tracker, priority);
2106 			sock_inuse_add(net, 1);
2107 		} else {
2108 			__netns_tracker_alloc(net, &sk->ns_tracker,
2109 					      false, priority);
2110 		}
2111 
2112 		sock_net_set(sk, net);
2113 		refcount_set(&sk->sk_wmem_alloc, 1);
2114 
2115 		mem_cgroup_sk_alloc(sk);
2116 		cgroup_sk_alloc(&sk->sk_cgrp_data);
2117 		sock_update_classid(&sk->sk_cgrp_data);
2118 		sock_update_netprioidx(&sk->sk_cgrp_data);
2119 		sk_tx_queue_clear(sk);
2120 	}
2121 
2122 	return sk;
2123 }
2124 EXPORT_SYMBOL(sk_alloc);
2125 
2126 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2127  * grace period. This is the case for UDP sockets and TCP listeners.
2128  */
2129 static void __sk_destruct(struct rcu_head *head)
2130 {
2131 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2132 	struct sk_filter *filter;
2133 
2134 	if (sk->sk_destruct)
2135 		sk->sk_destruct(sk);
2136 
2137 	filter = rcu_dereference_check(sk->sk_filter,
2138 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2139 	if (filter) {
2140 		sk_filter_uncharge(sk, filter);
2141 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2142 	}
2143 
2144 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2145 
2146 #ifdef CONFIG_BPF_SYSCALL
2147 	bpf_sk_storage_free(sk);
2148 #endif
2149 
2150 	if (atomic_read(&sk->sk_omem_alloc))
2151 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2152 			 __func__, atomic_read(&sk->sk_omem_alloc));
2153 
2154 	if (sk->sk_frag.page) {
2155 		put_page(sk->sk_frag.page);
2156 		sk->sk_frag.page = NULL;
2157 	}
2158 
2159 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2160 	put_cred(sk->sk_peer_cred);
2161 	put_pid(sk->sk_peer_pid);
2162 
2163 	if (likely(sk->sk_net_refcnt))
2164 		put_net_track(sock_net(sk), &sk->ns_tracker);
2165 	else
2166 		__netns_tracker_free(sock_net(sk), &sk->ns_tracker, false);
2167 
2168 	sk_prot_free(sk->sk_prot_creator, sk);
2169 }
2170 
2171 void sk_destruct(struct sock *sk)
2172 {
2173 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2174 
2175 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2176 		reuseport_detach_sock(sk);
2177 		use_call_rcu = true;
2178 	}
2179 
2180 	if (use_call_rcu)
2181 		call_rcu(&sk->sk_rcu, __sk_destruct);
2182 	else
2183 		__sk_destruct(&sk->sk_rcu);
2184 }
2185 
2186 static void __sk_free(struct sock *sk)
2187 {
2188 	if (likely(sk->sk_net_refcnt))
2189 		sock_inuse_add(sock_net(sk), -1);
2190 
2191 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2192 		sock_diag_broadcast_destroy(sk);
2193 	else
2194 		sk_destruct(sk);
2195 }
2196 
2197 void sk_free(struct sock *sk)
2198 {
2199 	/*
2200 	 * We subtract one from sk_wmem_alloc and can know if
2201 	 * some packets are still in some tx queue.
2202 	 * If not null, sock_wfree() will call __sk_free(sk) later
2203 	 */
2204 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2205 		__sk_free(sk);
2206 }
2207 EXPORT_SYMBOL(sk_free);
2208 
2209 static void sk_init_common(struct sock *sk)
2210 {
2211 	skb_queue_head_init(&sk->sk_receive_queue);
2212 	skb_queue_head_init(&sk->sk_write_queue);
2213 	skb_queue_head_init(&sk->sk_error_queue);
2214 
2215 	rwlock_init(&sk->sk_callback_lock);
2216 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2217 			af_rlock_keys + sk->sk_family,
2218 			af_family_rlock_key_strings[sk->sk_family]);
2219 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2220 			af_wlock_keys + sk->sk_family,
2221 			af_family_wlock_key_strings[sk->sk_family]);
2222 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2223 			af_elock_keys + sk->sk_family,
2224 			af_family_elock_key_strings[sk->sk_family]);
2225 	lockdep_set_class_and_name(&sk->sk_callback_lock,
2226 			af_callback_keys + sk->sk_family,
2227 			af_family_clock_key_strings[sk->sk_family]);
2228 }
2229 
2230 /**
2231  *	sk_clone_lock - clone a socket, and lock its clone
2232  *	@sk: the socket to clone
2233  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2234  *
2235  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2236  */
2237 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2238 {
2239 	struct proto *prot = READ_ONCE(sk->sk_prot);
2240 	struct sk_filter *filter;
2241 	bool is_charged = true;
2242 	struct sock *newsk;
2243 
2244 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2245 	if (!newsk)
2246 		goto out;
2247 
2248 	sock_copy(newsk, sk);
2249 
2250 	newsk->sk_prot_creator = prot;
2251 
2252 	/* SANITY */
2253 	if (likely(newsk->sk_net_refcnt)) {
2254 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2255 		sock_inuse_add(sock_net(newsk), 1);
2256 	} else {
2257 		/* Kernel sockets are not elevating the struct net refcount.
2258 		 * Instead, use a tracker to more easily detect if a layer
2259 		 * is not properly dismantling its kernel sockets at netns
2260 		 * destroy time.
2261 		 */
2262 		__netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2263 				      false, priority);
2264 	}
2265 	sk_node_init(&newsk->sk_node);
2266 	sock_lock_init(newsk);
2267 	bh_lock_sock(newsk);
2268 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2269 	newsk->sk_backlog.len = 0;
2270 
2271 	atomic_set(&newsk->sk_rmem_alloc, 0);
2272 
2273 	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2274 	refcount_set(&newsk->sk_wmem_alloc, 1);
2275 
2276 	atomic_set(&newsk->sk_omem_alloc, 0);
2277 	sk_init_common(newsk);
2278 
2279 	newsk->sk_dst_cache	= NULL;
2280 	newsk->sk_dst_pending_confirm = 0;
2281 	newsk->sk_wmem_queued	= 0;
2282 	newsk->sk_forward_alloc = 0;
2283 	newsk->sk_reserved_mem  = 0;
2284 	atomic_set(&newsk->sk_drops, 0);
2285 	newsk->sk_send_head	= NULL;
2286 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2287 	atomic_set(&newsk->sk_zckey, 0);
2288 
2289 	sock_reset_flag(newsk, SOCK_DONE);
2290 
2291 	/* sk->sk_memcg will be populated at accept() time */
2292 	newsk->sk_memcg = NULL;
2293 
2294 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2295 
2296 	rcu_read_lock();
2297 	filter = rcu_dereference(sk->sk_filter);
2298 	if (filter != NULL)
2299 		/* though it's an empty new sock, the charging may fail
2300 		 * if sysctl_optmem_max was changed between creation of
2301 		 * original socket and cloning
2302 		 */
2303 		is_charged = sk_filter_charge(newsk, filter);
2304 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2305 	rcu_read_unlock();
2306 
2307 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2308 		/* We need to make sure that we don't uncharge the new
2309 		 * socket if we couldn't charge it in the first place
2310 		 * as otherwise we uncharge the parent's filter.
2311 		 */
2312 		if (!is_charged)
2313 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2314 		sk_free_unlock_clone(newsk);
2315 		newsk = NULL;
2316 		goto out;
2317 	}
2318 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2319 
2320 	if (bpf_sk_storage_clone(sk, newsk)) {
2321 		sk_free_unlock_clone(newsk);
2322 		newsk = NULL;
2323 		goto out;
2324 	}
2325 
2326 	/* Clear sk_user_data if parent had the pointer tagged
2327 	 * as not suitable for copying when cloning.
2328 	 */
2329 	if (sk_user_data_is_nocopy(newsk))
2330 		newsk->sk_user_data = NULL;
2331 
2332 	newsk->sk_err	   = 0;
2333 	newsk->sk_err_soft = 0;
2334 	newsk->sk_priority = 0;
2335 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2336 
2337 	/* Before updating sk_refcnt, we must commit prior changes to memory
2338 	 * (Documentation/RCU/rculist_nulls.rst for details)
2339 	 */
2340 	smp_wmb();
2341 	refcount_set(&newsk->sk_refcnt, 2);
2342 
2343 	/* Increment the counter in the same struct proto as the master
2344 	 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
2345 	 * is the same as sk->sk_prot->socks, as this field was copied
2346 	 * with memcpy).
2347 	 *
2348 	 * This _changes_ the previous behaviour, where
2349 	 * tcp_create_openreq_child always was incrementing the
2350 	 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
2351 	 * to be taken into account in all callers. -acme
2352 	 */
2353 	sk_refcnt_debug_inc(newsk);
2354 	sk_set_socket(newsk, NULL);
2355 	sk_tx_queue_clear(newsk);
2356 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2357 
2358 	if (newsk->sk_prot->sockets_allocated)
2359 		sk_sockets_allocated_inc(newsk);
2360 
2361 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2362 		net_enable_timestamp();
2363 out:
2364 	return newsk;
2365 }
2366 EXPORT_SYMBOL_GPL(sk_clone_lock);
2367 
2368 void sk_free_unlock_clone(struct sock *sk)
2369 {
2370 	/* It is still raw copy of parent, so invalidate
2371 	 * destructor and make plain sk_free() */
2372 	sk->sk_destruct = NULL;
2373 	bh_unlock_sock(sk);
2374 	sk_free(sk);
2375 }
2376 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2377 
2378 static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst)
2379 {
2380 	bool is_ipv6 = false;
2381 	u32 max_size;
2382 
2383 #if IS_ENABLED(CONFIG_IPV6)
2384 	is_ipv6 = (sk->sk_family == AF_INET6 &&
2385 		   !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2386 #endif
2387 	/* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2388 	max_size = is_ipv6 ? READ_ONCE(dst->dev->gso_max_size) :
2389 			READ_ONCE(dst->dev->gso_ipv4_max_size);
2390 	if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2391 		max_size = GSO_LEGACY_MAX_SIZE;
2392 
2393 	return max_size - (MAX_TCP_HEADER + 1);
2394 }
2395 
2396 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2397 {
2398 	u32 max_segs = 1;
2399 
2400 	sk_dst_set(sk, dst);
2401 	sk->sk_route_caps = dst->dev->features;
2402 	if (sk_is_tcp(sk))
2403 		sk->sk_route_caps |= NETIF_F_GSO;
2404 	if (sk->sk_route_caps & NETIF_F_GSO)
2405 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2406 	if (unlikely(sk->sk_gso_disabled))
2407 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2408 	if (sk_can_gso(sk)) {
2409 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2410 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2411 		} else {
2412 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2413 			sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst);
2414 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2415 			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2416 		}
2417 	}
2418 	sk->sk_gso_max_segs = max_segs;
2419 }
2420 EXPORT_SYMBOL_GPL(sk_setup_caps);
2421 
2422 /*
2423  *	Simple resource managers for sockets.
2424  */
2425 
2426 
2427 /*
2428  * Write buffer destructor automatically called from kfree_skb.
2429  */
2430 void sock_wfree(struct sk_buff *skb)
2431 {
2432 	struct sock *sk = skb->sk;
2433 	unsigned int len = skb->truesize;
2434 	bool free;
2435 
2436 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2437 		if (sock_flag(sk, SOCK_RCU_FREE) &&
2438 		    sk->sk_write_space == sock_def_write_space) {
2439 			rcu_read_lock();
2440 			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2441 			sock_def_write_space_wfree(sk);
2442 			rcu_read_unlock();
2443 			if (unlikely(free))
2444 				__sk_free(sk);
2445 			return;
2446 		}
2447 
2448 		/*
2449 		 * Keep a reference on sk_wmem_alloc, this will be released
2450 		 * after sk_write_space() call
2451 		 */
2452 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2453 		sk->sk_write_space(sk);
2454 		len = 1;
2455 	}
2456 	/*
2457 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2458 	 * could not do because of in-flight packets
2459 	 */
2460 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2461 		__sk_free(sk);
2462 }
2463 EXPORT_SYMBOL(sock_wfree);
2464 
2465 /* This variant of sock_wfree() is used by TCP,
2466  * since it sets SOCK_USE_WRITE_QUEUE.
2467  */
2468 void __sock_wfree(struct sk_buff *skb)
2469 {
2470 	struct sock *sk = skb->sk;
2471 
2472 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2473 		__sk_free(sk);
2474 }
2475 
2476 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2477 {
2478 	skb_orphan(skb);
2479 	skb->sk = sk;
2480 #ifdef CONFIG_INET
2481 	if (unlikely(!sk_fullsock(sk))) {
2482 		skb->destructor = sock_edemux;
2483 		sock_hold(sk);
2484 		return;
2485 	}
2486 #endif
2487 	skb->destructor = sock_wfree;
2488 	skb_set_hash_from_sk(skb, sk);
2489 	/*
2490 	 * We used to take a refcount on sk, but following operation
2491 	 * is enough to guarantee sk_free() wont free this sock until
2492 	 * all in-flight packets are completed
2493 	 */
2494 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2495 }
2496 EXPORT_SYMBOL(skb_set_owner_w);
2497 
2498 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2499 {
2500 #ifdef CONFIG_TLS_DEVICE
2501 	/* Drivers depend on in-order delivery for crypto offload,
2502 	 * partial orphan breaks out-of-order-OK logic.
2503 	 */
2504 	if (skb->decrypted)
2505 		return false;
2506 #endif
2507 	return (skb->destructor == sock_wfree ||
2508 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2509 }
2510 
2511 /* This helper is used by netem, as it can hold packets in its
2512  * delay queue. We want to allow the owner socket to send more
2513  * packets, as if they were already TX completed by a typical driver.
2514  * But we also want to keep skb->sk set because some packet schedulers
2515  * rely on it (sch_fq for example).
2516  */
2517 void skb_orphan_partial(struct sk_buff *skb)
2518 {
2519 	if (skb_is_tcp_pure_ack(skb))
2520 		return;
2521 
2522 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2523 		return;
2524 
2525 	skb_orphan(skb);
2526 }
2527 EXPORT_SYMBOL(skb_orphan_partial);
2528 
2529 /*
2530  * Read buffer destructor automatically called from kfree_skb.
2531  */
2532 void sock_rfree(struct sk_buff *skb)
2533 {
2534 	struct sock *sk = skb->sk;
2535 	unsigned int len = skb->truesize;
2536 
2537 	atomic_sub(len, &sk->sk_rmem_alloc);
2538 	sk_mem_uncharge(sk, len);
2539 }
2540 EXPORT_SYMBOL(sock_rfree);
2541 
2542 /*
2543  * Buffer destructor for skbs that are not used directly in read or write
2544  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2545  */
2546 void sock_efree(struct sk_buff *skb)
2547 {
2548 	sock_put(skb->sk);
2549 }
2550 EXPORT_SYMBOL(sock_efree);
2551 
2552 /* Buffer destructor for prefetch/receive path where reference count may
2553  * not be held, e.g. for listen sockets.
2554  */
2555 #ifdef CONFIG_INET
2556 void sock_pfree(struct sk_buff *skb)
2557 {
2558 	if (sk_is_refcounted(skb->sk))
2559 		sock_gen_put(skb->sk);
2560 }
2561 EXPORT_SYMBOL(sock_pfree);
2562 #endif /* CONFIG_INET */
2563 
2564 kuid_t sock_i_uid(struct sock *sk)
2565 {
2566 	kuid_t uid;
2567 
2568 	read_lock_bh(&sk->sk_callback_lock);
2569 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2570 	read_unlock_bh(&sk->sk_callback_lock);
2571 	return uid;
2572 }
2573 EXPORT_SYMBOL(sock_i_uid);
2574 
2575 unsigned long sock_i_ino(struct sock *sk)
2576 {
2577 	unsigned long ino;
2578 
2579 	read_lock_bh(&sk->sk_callback_lock);
2580 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2581 	read_unlock_bh(&sk->sk_callback_lock);
2582 	return ino;
2583 }
2584 EXPORT_SYMBOL(sock_i_ino);
2585 
2586 /*
2587  * Allocate a skb from the socket's send buffer.
2588  */
2589 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2590 			     gfp_t priority)
2591 {
2592 	if (force ||
2593 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2594 		struct sk_buff *skb = alloc_skb(size, priority);
2595 
2596 		if (skb) {
2597 			skb_set_owner_w(skb, sk);
2598 			return skb;
2599 		}
2600 	}
2601 	return NULL;
2602 }
2603 EXPORT_SYMBOL(sock_wmalloc);
2604 
2605 static void sock_ofree(struct sk_buff *skb)
2606 {
2607 	struct sock *sk = skb->sk;
2608 
2609 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2610 }
2611 
2612 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2613 			     gfp_t priority)
2614 {
2615 	struct sk_buff *skb;
2616 
2617 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2618 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2619 	    READ_ONCE(sysctl_optmem_max))
2620 		return NULL;
2621 
2622 	skb = alloc_skb(size, priority);
2623 	if (!skb)
2624 		return NULL;
2625 
2626 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2627 	skb->sk = sk;
2628 	skb->destructor = sock_ofree;
2629 	return skb;
2630 }
2631 
2632 /*
2633  * Allocate a memory block from the socket's option memory buffer.
2634  */
2635 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2636 {
2637 	int optmem_max = READ_ONCE(sysctl_optmem_max);
2638 
2639 	if ((unsigned int)size <= optmem_max &&
2640 	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2641 		void *mem;
2642 		/* First do the add, to avoid the race if kmalloc
2643 		 * might sleep.
2644 		 */
2645 		atomic_add(size, &sk->sk_omem_alloc);
2646 		mem = kmalloc(size, priority);
2647 		if (mem)
2648 			return mem;
2649 		atomic_sub(size, &sk->sk_omem_alloc);
2650 	}
2651 	return NULL;
2652 }
2653 EXPORT_SYMBOL(sock_kmalloc);
2654 
2655 /* Free an option memory block. Note, we actually want the inline
2656  * here as this allows gcc to detect the nullify and fold away the
2657  * condition entirely.
2658  */
2659 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2660 				  const bool nullify)
2661 {
2662 	if (WARN_ON_ONCE(!mem))
2663 		return;
2664 	if (nullify)
2665 		kfree_sensitive(mem);
2666 	else
2667 		kfree(mem);
2668 	atomic_sub(size, &sk->sk_omem_alloc);
2669 }
2670 
2671 void sock_kfree_s(struct sock *sk, void *mem, int size)
2672 {
2673 	__sock_kfree_s(sk, mem, size, false);
2674 }
2675 EXPORT_SYMBOL(sock_kfree_s);
2676 
2677 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2678 {
2679 	__sock_kfree_s(sk, mem, size, true);
2680 }
2681 EXPORT_SYMBOL(sock_kzfree_s);
2682 
2683 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2684    I think, these locks should be removed for datagram sockets.
2685  */
2686 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2687 {
2688 	DEFINE_WAIT(wait);
2689 
2690 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2691 	for (;;) {
2692 		if (!timeo)
2693 			break;
2694 		if (signal_pending(current))
2695 			break;
2696 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2697 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2698 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2699 			break;
2700 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2701 			break;
2702 		if (sk->sk_err)
2703 			break;
2704 		timeo = schedule_timeout(timeo);
2705 	}
2706 	finish_wait(sk_sleep(sk), &wait);
2707 	return timeo;
2708 }
2709 
2710 
2711 /*
2712  *	Generic send/receive buffer handlers
2713  */
2714 
2715 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2716 				     unsigned long data_len, int noblock,
2717 				     int *errcode, int max_page_order)
2718 {
2719 	struct sk_buff *skb;
2720 	long timeo;
2721 	int err;
2722 
2723 	timeo = sock_sndtimeo(sk, noblock);
2724 	for (;;) {
2725 		err = sock_error(sk);
2726 		if (err != 0)
2727 			goto failure;
2728 
2729 		err = -EPIPE;
2730 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2731 			goto failure;
2732 
2733 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2734 			break;
2735 
2736 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2737 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2738 		err = -EAGAIN;
2739 		if (!timeo)
2740 			goto failure;
2741 		if (signal_pending(current))
2742 			goto interrupted;
2743 		timeo = sock_wait_for_wmem(sk, timeo);
2744 	}
2745 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2746 				   errcode, sk->sk_allocation);
2747 	if (skb)
2748 		skb_set_owner_w(skb, sk);
2749 	return skb;
2750 
2751 interrupted:
2752 	err = sock_intr_errno(timeo);
2753 failure:
2754 	*errcode = err;
2755 	return NULL;
2756 }
2757 EXPORT_SYMBOL(sock_alloc_send_pskb);
2758 
2759 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2760 		     struct sockcm_cookie *sockc)
2761 {
2762 	u32 tsflags;
2763 
2764 	switch (cmsg->cmsg_type) {
2765 	case SO_MARK:
2766 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2767 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2768 			return -EPERM;
2769 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2770 			return -EINVAL;
2771 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2772 		break;
2773 	case SO_TIMESTAMPING_OLD:
2774 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2775 			return -EINVAL;
2776 
2777 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2778 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2779 			return -EINVAL;
2780 
2781 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2782 		sockc->tsflags |= tsflags;
2783 		break;
2784 	case SCM_TXTIME:
2785 		if (!sock_flag(sk, SOCK_TXTIME))
2786 			return -EINVAL;
2787 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2788 			return -EINVAL;
2789 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2790 		break;
2791 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2792 	case SCM_RIGHTS:
2793 	case SCM_CREDENTIALS:
2794 		break;
2795 	default:
2796 		return -EINVAL;
2797 	}
2798 	return 0;
2799 }
2800 EXPORT_SYMBOL(__sock_cmsg_send);
2801 
2802 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2803 		   struct sockcm_cookie *sockc)
2804 {
2805 	struct cmsghdr *cmsg;
2806 	int ret;
2807 
2808 	for_each_cmsghdr(cmsg, msg) {
2809 		if (!CMSG_OK(msg, cmsg))
2810 			return -EINVAL;
2811 		if (cmsg->cmsg_level != SOL_SOCKET)
2812 			continue;
2813 		ret = __sock_cmsg_send(sk, cmsg, sockc);
2814 		if (ret)
2815 			return ret;
2816 	}
2817 	return 0;
2818 }
2819 EXPORT_SYMBOL(sock_cmsg_send);
2820 
2821 static void sk_enter_memory_pressure(struct sock *sk)
2822 {
2823 	if (!sk->sk_prot->enter_memory_pressure)
2824 		return;
2825 
2826 	sk->sk_prot->enter_memory_pressure(sk);
2827 }
2828 
2829 static void sk_leave_memory_pressure(struct sock *sk)
2830 {
2831 	if (sk->sk_prot->leave_memory_pressure) {
2832 		sk->sk_prot->leave_memory_pressure(sk);
2833 	} else {
2834 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2835 
2836 		if (memory_pressure && READ_ONCE(*memory_pressure))
2837 			WRITE_ONCE(*memory_pressure, 0);
2838 	}
2839 }
2840 
2841 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2842 
2843 /**
2844  * skb_page_frag_refill - check that a page_frag contains enough room
2845  * @sz: minimum size of the fragment we want to get
2846  * @pfrag: pointer to page_frag
2847  * @gfp: priority for memory allocation
2848  *
2849  * Note: While this allocator tries to use high order pages, there is
2850  * no guarantee that allocations succeed. Therefore, @sz MUST be
2851  * less or equal than PAGE_SIZE.
2852  */
2853 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2854 {
2855 	if (pfrag->page) {
2856 		if (page_ref_count(pfrag->page) == 1) {
2857 			pfrag->offset = 0;
2858 			return true;
2859 		}
2860 		if (pfrag->offset + sz <= pfrag->size)
2861 			return true;
2862 		put_page(pfrag->page);
2863 	}
2864 
2865 	pfrag->offset = 0;
2866 	if (SKB_FRAG_PAGE_ORDER &&
2867 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2868 		/* Avoid direct reclaim but allow kswapd to wake */
2869 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2870 					  __GFP_COMP | __GFP_NOWARN |
2871 					  __GFP_NORETRY,
2872 					  SKB_FRAG_PAGE_ORDER);
2873 		if (likely(pfrag->page)) {
2874 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2875 			return true;
2876 		}
2877 	}
2878 	pfrag->page = alloc_page(gfp);
2879 	if (likely(pfrag->page)) {
2880 		pfrag->size = PAGE_SIZE;
2881 		return true;
2882 	}
2883 	return false;
2884 }
2885 EXPORT_SYMBOL(skb_page_frag_refill);
2886 
2887 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2888 {
2889 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2890 		return true;
2891 
2892 	sk_enter_memory_pressure(sk);
2893 	sk_stream_moderate_sndbuf(sk);
2894 	return false;
2895 }
2896 EXPORT_SYMBOL(sk_page_frag_refill);
2897 
2898 void __lock_sock(struct sock *sk)
2899 	__releases(&sk->sk_lock.slock)
2900 	__acquires(&sk->sk_lock.slock)
2901 {
2902 	DEFINE_WAIT(wait);
2903 
2904 	for (;;) {
2905 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2906 					TASK_UNINTERRUPTIBLE);
2907 		spin_unlock_bh(&sk->sk_lock.slock);
2908 		schedule();
2909 		spin_lock_bh(&sk->sk_lock.slock);
2910 		if (!sock_owned_by_user(sk))
2911 			break;
2912 	}
2913 	finish_wait(&sk->sk_lock.wq, &wait);
2914 }
2915 
2916 void __release_sock(struct sock *sk)
2917 	__releases(&sk->sk_lock.slock)
2918 	__acquires(&sk->sk_lock.slock)
2919 {
2920 	struct sk_buff *skb, *next;
2921 
2922 	while ((skb = sk->sk_backlog.head) != NULL) {
2923 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2924 
2925 		spin_unlock_bh(&sk->sk_lock.slock);
2926 
2927 		do {
2928 			next = skb->next;
2929 			prefetch(next);
2930 			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2931 			skb_mark_not_on_list(skb);
2932 			sk_backlog_rcv(sk, skb);
2933 
2934 			cond_resched();
2935 
2936 			skb = next;
2937 		} while (skb != NULL);
2938 
2939 		spin_lock_bh(&sk->sk_lock.slock);
2940 	}
2941 
2942 	/*
2943 	 * Doing the zeroing here guarantee we can not loop forever
2944 	 * while a wild producer attempts to flood us.
2945 	 */
2946 	sk->sk_backlog.len = 0;
2947 }
2948 
2949 void __sk_flush_backlog(struct sock *sk)
2950 {
2951 	spin_lock_bh(&sk->sk_lock.slock);
2952 	__release_sock(sk);
2953 	spin_unlock_bh(&sk->sk_lock.slock);
2954 }
2955 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
2956 
2957 /**
2958  * sk_wait_data - wait for data to arrive at sk_receive_queue
2959  * @sk:    sock to wait on
2960  * @timeo: for how long
2961  * @skb:   last skb seen on sk_receive_queue
2962  *
2963  * Now socket state including sk->sk_err is changed only under lock,
2964  * hence we may omit checks after joining wait queue.
2965  * We check receive queue before schedule() only as optimization;
2966  * it is very likely that release_sock() added new data.
2967  */
2968 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2969 {
2970 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2971 	int rc;
2972 
2973 	add_wait_queue(sk_sleep(sk), &wait);
2974 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2975 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2976 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2977 	remove_wait_queue(sk_sleep(sk), &wait);
2978 	return rc;
2979 }
2980 EXPORT_SYMBOL(sk_wait_data);
2981 
2982 /**
2983  *	__sk_mem_raise_allocated - increase memory_allocated
2984  *	@sk: socket
2985  *	@size: memory size to allocate
2986  *	@amt: pages to allocate
2987  *	@kind: allocation type
2988  *
2989  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2990  */
2991 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2992 {
2993 	bool memcg_charge = mem_cgroup_sockets_enabled && sk->sk_memcg;
2994 	struct proto *prot = sk->sk_prot;
2995 	bool charged = true;
2996 	long allocated;
2997 
2998 	sk_memory_allocated_add(sk, amt);
2999 	allocated = sk_memory_allocated(sk);
3000 	if (memcg_charge &&
3001 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt,
3002 						gfp_memcg_charge())))
3003 		goto suppress_allocation;
3004 
3005 	/* Under limit. */
3006 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
3007 		sk_leave_memory_pressure(sk);
3008 		return 1;
3009 	}
3010 
3011 	/* Under pressure. */
3012 	if (allocated > sk_prot_mem_limits(sk, 1))
3013 		sk_enter_memory_pressure(sk);
3014 
3015 	/* Over hard limit. */
3016 	if (allocated > sk_prot_mem_limits(sk, 2))
3017 		goto suppress_allocation;
3018 
3019 	/* guarantee minimum buffer size under pressure */
3020 	if (kind == SK_MEM_RECV) {
3021 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3022 			return 1;
3023 
3024 	} else { /* SK_MEM_SEND */
3025 		int wmem0 = sk_get_wmem0(sk, prot);
3026 
3027 		if (sk->sk_type == SOCK_STREAM) {
3028 			if (sk->sk_wmem_queued < wmem0)
3029 				return 1;
3030 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3031 				return 1;
3032 		}
3033 	}
3034 
3035 	if (sk_has_memory_pressure(sk)) {
3036 		u64 alloc;
3037 
3038 		if (!sk_under_memory_pressure(sk))
3039 			return 1;
3040 		alloc = sk_sockets_allocated_read_positive(sk);
3041 		if (sk_prot_mem_limits(sk, 2) > alloc *
3042 		    sk_mem_pages(sk->sk_wmem_queued +
3043 				 atomic_read(&sk->sk_rmem_alloc) +
3044 				 sk->sk_forward_alloc))
3045 			return 1;
3046 	}
3047 
3048 suppress_allocation:
3049 
3050 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3051 		sk_stream_moderate_sndbuf(sk);
3052 
3053 		/* Fail only if socket is _under_ its sndbuf.
3054 		 * In this case we cannot block, so that we have to fail.
3055 		 */
3056 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3057 			/* Force charge with __GFP_NOFAIL */
3058 			if (memcg_charge && !charged) {
3059 				mem_cgroup_charge_skmem(sk->sk_memcg, amt,
3060 					gfp_memcg_charge() | __GFP_NOFAIL);
3061 			}
3062 			return 1;
3063 		}
3064 	}
3065 
3066 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3067 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3068 
3069 	sk_memory_allocated_sub(sk, amt);
3070 
3071 	if (memcg_charge && charged)
3072 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
3073 
3074 	return 0;
3075 }
3076 
3077 /**
3078  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3079  *	@sk: socket
3080  *	@size: memory size to allocate
3081  *	@kind: allocation type
3082  *
3083  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3084  *	rmem allocation. This function assumes that protocols which have
3085  *	memory_pressure use sk_wmem_queued as write buffer accounting.
3086  */
3087 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3088 {
3089 	int ret, amt = sk_mem_pages(size);
3090 
3091 	sk->sk_forward_alloc += amt << PAGE_SHIFT;
3092 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3093 	if (!ret)
3094 		sk->sk_forward_alloc -= amt << PAGE_SHIFT;
3095 	return ret;
3096 }
3097 EXPORT_SYMBOL(__sk_mem_schedule);
3098 
3099 /**
3100  *	__sk_mem_reduce_allocated - reclaim memory_allocated
3101  *	@sk: socket
3102  *	@amount: number of quanta
3103  *
3104  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3105  */
3106 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3107 {
3108 	sk_memory_allocated_sub(sk, amount);
3109 
3110 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3111 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3112 
3113 	if (sk_under_memory_pressure(sk) &&
3114 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3115 		sk_leave_memory_pressure(sk);
3116 }
3117 
3118 /**
3119  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3120  *	@sk: socket
3121  *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3122  */
3123 void __sk_mem_reclaim(struct sock *sk, int amount)
3124 {
3125 	amount >>= PAGE_SHIFT;
3126 	sk->sk_forward_alloc -= amount << PAGE_SHIFT;
3127 	__sk_mem_reduce_allocated(sk, amount);
3128 }
3129 EXPORT_SYMBOL(__sk_mem_reclaim);
3130 
3131 int sk_set_peek_off(struct sock *sk, int val)
3132 {
3133 	sk->sk_peek_off = val;
3134 	return 0;
3135 }
3136 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3137 
3138 /*
3139  * Set of default routines for initialising struct proto_ops when
3140  * the protocol does not support a particular function. In certain
3141  * cases where it makes no sense for a protocol to have a "do nothing"
3142  * function, some default processing is provided.
3143  */
3144 
3145 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3146 {
3147 	return -EOPNOTSUPP;
3148 }
3149 EXPORT_SYMBOL(sock_no_bind);
3150 
3151 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3152 		    int len, int flags)
3153 {
3154 	return -EOPNOTSUPP;
3155 }
3156 EXPORT_SYMBOL(sock_no_connect);
3157 
3158 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3159 {
3160 	return -EOPNOTSUPP;
3161 }
3162 EXPORT_SYMBOL(sock_no_socketpair);
3163 
3164 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3165 		   bool kern)
3166 {
3167 	return -EOPNOTSUPP;
3168 }
3169 EXPORT_SYMBOL(sock_no_accept);
3170 
3171 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3172 		    int peer)
3173 {
3174 	return -EOPNOTSUPP;
3175 }
3176 EXPORT_SYMBOL(sock_no_getname);
3177 
3178 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3179 {
3180 	return -EOPNOTSUPP;
3181 }
3182 EXPORT_SYMBOL(sock_no_ioctl);
3183 
3184 int sock_no_listen(struct socket *sock, int backlog)
3185 {
3186 	return -EOPNOTSUPP;
3187 }
3188 EXPORT_SYMBOL(sock_no_listen);
3189 
3190 int sock_no_shutdown(struct socket *sock, int how)
3191 {
3192 	return -EOPNOTSUPP;
3193 }
3194 EXPORT_SYMBOL(sock_no_shutdown);
3195 
3196 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3197 {
3198 	return -EOPNOTSUPP;
3199 }
3200 EXPORT_SYMBOL(sock_no_sendmsg);
3201 
3202 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3203 {
3204 	return -EOPNOTSUPP;
3205 }
3206 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3207 
3208 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3209 		    int flags)
3210 {
3211 	return -EOPNOTSUPP;
3212 }
3213 EXPORT_SYMBOL(sock_no_recvmsg);
3214 
3215 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3216 {
3217 	/* Mirror missing mmap method error code */
3218 	return -ENODEV;
3219 }
3220 EXPORT_SYMBOL(sock_no_mmap);
3221 
3222 /*
3223  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3224  * various sock-based usage counts.
3225  */
3226 void __receive_sock(struct file *file)
3227 {
3228 	struct socket *sock;
3229 
3230 	sock = sock_from_file(file);
3231 	if (sock) {
3232 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3233 		sock_update_classid(&sock->sk->sk_cgrp_data);
3234 	}
3235 }
3236 
3237 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
3238 {
3239 	ssize_t res;
3240 	struct msghdr msg = {.msg_flags = flags};
3241 	struct kvec iov;
3242 	char *kaddr = kmap(page);
3243 	iov.iov_base = kaddr + offset;
3244 	iov.iov_len = size;
3245 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
3246 	kunmap(page);
3247 	return res;
3248 }
3249 EXPORT_SYMBOL(sock_no_sendpage);
3250 
3251 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
3252 				int offset, size_t size, int flags)
3253 {
3254 	ssize_t res;
3255 	struct msghdr msg = {.msg_flags = flags};
3256 	struct kvec iov;
3257 	char *kaddr = kmap(page);
3258 
3259 	iov.iov_base = kaddr + offset;
3260 	iov.iov_len = size;
3261 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
3262 	kunmap(page);
3263 	return res;
3264 }
3265 EXPORT_SYMBOL(sock_no_sendpage_locked);
3266 
3267 /*
3268  *	Default Socket Callbacks
3269  */
3270 
3271 static void sock_def_wakeup(struct sock *sk)
3272 {
3273 	struct socket_wq *wq;
3274 
3275 	rcu_read_lock();
3276 	wq = rcu_dereference(sk->sk_wq);
3277 	if (skwq_has_sleeper(wq))
3278 		wake_up_interruptible_all(&wq->wait);
3279 	rcu_read_unlock();
3280 }
3281 
3282 static void sock_def_error_report(struct sock *sk)
3283 {
3284 	struct socket_wq *wq;
3285 
3286 	rcu_read_lock();
3287 	wq = rcu_dereference(sk->sk_wq);
3288 	if (skwq_has_sleeper(wq))
3289 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3290 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3291 	rcu_read_unlock();
3292 }
3293 
3294 void sock_def_readable(struct sock *sk)
3295 {
3296 	struct socket_wq *wq;
3297 
3298 	trace_sk_data_ready(sk);
3299 
3300 	rcu_read_lock();
3301 	wq = rcu_dereference(sk->sk_wq);
3302 	if (skwq_has_sleeper(wq))
3303 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3304 						EPOLLRDNORM | EPOLLRDBAND);
3305 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3306 	rcu_read_unlock();
3307 }
3308 
3309 static void sock_def_write_space(struct sock *sk)
3310 {
3311 	struct socket_wq *wq;
3312 
3313 	rcu_read_lock();
3314 
3315 	/* Do not wake up a writer until he can make "significant"
3316 	 * progress.  --DaveM
3317 	 */
3318 	if (sock_writeable(sk)) {
3319 		wq = rcu_dereference(sk->sk_wq);
3320 		if (skwq_has_sleeper(wq))
3321 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3322 						EPOLLWRNORM | EPOLLWRBAND);
3323 
3324 		/* Should agree with poll, otherwise some programs break */
3325 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3326 	}
3327 
3328 	rcu_read_unlock();
3329 }
3330 
3331 /* An optimised version of sock_def_write_space(), should only be called
3332  * for SOCK_RCU_FREE sockets under RCU read section and after putting
3333  * ->sk_wmem_alloc.
3334  */
3335 static void sock_def_write_space_wfree(struct sock *sk)
3336 {
3337 	/* Do not wake up a writer until he can make "significant"
3338 	 * progress.  --DaveM
3339 	 */
3340 	if (sock_writeable(sk)) {
3341 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3342 
3343 		/* rely on refcount_sub from sock_wfree() */
3344 		smp_mb__after_atomic();
3345 		if (wq && waitqueue_active(&wq->wait))
3346 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3347 						EPOLLWRNORM | EPOLLWRBAND);
3348 
3349 		/* Should agree with poll, otherwise some programs break */
3350 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3351 	}
3352 }
3353 
3354 static void sock_def_destruct(struct sock *sk)
3355 {
3356 }
3357 
3358 void sk_send_sigurg(struct sock *sk)
3359 {
3360 	if (sk->sk_socket && sk->sk_socket->file)
3361 		if (send_sigurg(&sk->sk_socket->file->f_owner))
3362 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3363 }
3364 EXPORT_SYMBOL(sk_send_sigurg);
3365 
3366 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3367 		    unsigned long expires)
3368 {
3369 	if (!mod_timer(timer, expires))
3370 		sock_hold(sk);
3371 }
3372 EXPORT_SYMBOL(sk_reset_timer);
3373 
3374 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3375 {
3376 	if (del_timer(timer))
3377 		__sock_put(sk);
3378 }
3379 EXPORT_SYMBOL(sk_stop_timer);
3380 
3381 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3382 {
3383 	if (del_timer_sync(timer))
3384 		__sock_put(sk);
3385 }
3386 EXPORT_SYMBOL(sk_stop_timer_sync);
3387 
3388 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3389 {
3390 	sk_init_common(sk);
3391 	sk->sk_send_head	=	NULL;
3392 
3393 	timer_setup(&sk->sk_timer, NULL, 0);
3394 
3395 	sk->sk_allocation	=	GFP_KERNEL;
3396 	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3397 	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3398 	sk->sk_state		=	TCP_CLOSE;
3399 	sk->sk_use_task_frag	=	true;
3400 	sk_set_socket(sk, sock);
3401 
3402 	sock_set_flag(sk, SOCK_ZAPPED);
3403 
3404 	if (sock) {
3405 		sk->sk_type	=	sock->type;
3406 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3407 		sock->sk	=	sk;
3408 	} else {
3409 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3410 	}
3411 	sk->sk_uid	=	uid;
3412 
3413 	rwlock_init(&sk->sk_callback_lock);
3414 	if (sk->sk_kern_sock)
3415 		lockdep_set_class_and_name(
3416 			&sk->sk_callback_lock,
3417 			af_kern_callback_keys + sk->sk_family,
3418 			af_family_kern_clock_key_strings[sk->sk_family]);
3419 	else
3420 		lockdep_set_class_and_name(
3421 			&sk->sk_callback_lock,
3422 			af_callback_keys + sk->sk_family,
3423 			af_family_clock_key_strings[sk->sk_family]);
3424 
3425 	sk->sk_state_change	=	sock_def_wakeup;
3426 	sk->sk_data_ready	=	sock_def_readable;
3427 	sk->sk_write_space	=	sock_def_write_space;
3428 	sk->sk_error_report	=	sock_def_error_report;
3429 	sk->sk_destruct		=	sock_def_destruct;
3430 
3431 	sk->sk_frag.page	=	NULL;
3432 	sk->sk_frag.offset	=	0;
3433 	sk->sk_peek_off		=	-1;
3434 
3435 	sk->sk_peer_pid 	=	NULL;
3436 	sk->sk_peer_cred	=	NULL;
3437 	spin_lock_init(&sk->sk_peer_lock);
3438 
3439 	sk->sk_write_pending	=	0;
3440 	sk->sk_rcvlowat		=	1;
3441 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3442 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3443 
3444 	sk->sk_stamp = SK_DEFAULT_STAMP;
3445 #if BITS_PER_LONG==32
3446 	seqlock_init(&sk->sk_stamp_seq);
3447 #endif
3448 	atomic_set(&sk->sk_zckey, 0);
3449 
3450 #ifdef CONFIG_NET_RX_BUSY_POLL
3451 	sk->sk_napi_id		=	0;
3452 	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3453 #endif
3454 
3455 	sk->sk_max_pacing_rate = ~0UL;
3456 	sk->sk_pacing_rate = ~0UL;
3457 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3458 	sk->sk_incoming_cpu = -1;
3459 
3460 	sk_rx_queue_clear(sk);
3461 	/*
3462 	 * Before updating sk_refcnt, we must commit prior changes to memory
3463 	 * (Documentation/RCU/rculist_nulls.rst for details)
3464 	 */
3465 	smp_wmb();
3466 	refcount_set(&sk->sk_refcnt, 1);
3467 	atomic_set(&sk->sk_drops, 0);
3468 }
3469 EXPORT_SYMBOL(sock_init_data_uid);
3470 
3471 void sock_init_data(struct socket *sock, struct sock *sk)
3472 {
3473 	kuid_t uid = sock ?
3474 		SOCK_INODE(sock)->i_uid :
3475 		make_kuid(sock_net(sk)->user_ns, 0);
3476 
3477 	sock_init_data_uid(sock, sk, uid);
3478 }
3479 EXPORT_SYMBOL(sock_init_data);
3480 
3481 void lock_sock_nested(struct sock *sk, int subclass)
3482 {
3483 	/* The sk_lock has mutex_lock() semantics here. */
3484 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3485 
3486 	might_sleep();
3487 	spin_lock_bh(&sk->sk_lock.slock);
3488 	if (sock_owned_by_user_nocheck(sk))
3489 		__lock_sock(sk);
3490 	sk->sk_lock.owned = 1;
3491 	spin_unlock_bh(&sk->sk_lock.slock);
3492 }
3493 EXPORT_SYMBOL(lock_sock_nested);
3494 
3495 void release_sock(struct sock *sk)
3496 {
3497 	spin_lock_bh(&sk->sk_lock.slock);
3498 	if (sk->sk_backlog.tail)
3499 		__release_sock(sk);
3500 
3501 	/* Warning : release_cb() might need to release sk ownership,
3502 	 * ie call sock_release_ownership(sk) before us.
3503 	 */
3504 	if (sk->sk_prot->release_cb)
3505 		sk->sk_prot->release_cb(sk);
3506 
3507 	sock_release_ownership(sk);
3508 	if (waitqueue_active(&sk->sk_lock.wq))
3509 		wake_up(&sk->sk_lock.wq);
3510 	spin_unlock_bh(&sk->sk_lock.slock);
3511 }
3512 EXPORT_SYMBOL(release_sock);
3513 
3514 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3515 {
3516 	might_sleep();
3517 	spin_lock_bh(&sk->sk_lock.slock);
3518 
3519 	if (!sock_owned_by_user_nocheck(sk)) {
3520 		/*
3521 		 * Fast path return with bottom halves disabled and
3522 		 * sock::sk_lock.slock held.
3523 		 *
3524 		 * The 'mutex' is not contended and holding
3525 		 * sock::sk_lock.slock prevents all other lockers to
3526 		 * proceed so the corresponding unlock_sock_fast() can
3527 		 * avoid the slow path of release_sock() completely and
3528 		 * just release slock.
3529 		 *
3530 		 * From a semantical POV this is equivalent to 'acquiring'
3531 		 * the 'mutex', hence the corresponding lockdep
3532 		 * mutex_release() has to happen in the fast path of
3533 		 * unlock_sock_fast().
3534 		 */
3535 		return false;
3536 	}
3537 
3538 	__lock_sock(sk);
3539 	sk->sk_lock.owned = 1;
3540 	__acquire(&sk->sk_lock.slock);
3541 	spin_unlock_bh(&sk->sk_lock.slock);
3542 	return true;
3543 }
3544 EXPORT_SYMBOL(__lock_sock_fast);
3545 
3546 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3547 		   bool timeval, bool time32)
3548 {
3549 	struct sock *sk = sock->sk;
3550 	struct timespec64 ts;
3551 
3552 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3553 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3554 	if (ts.tv_sec == -1)
3555 		return -ENOENT;
3556 	if (ts.tv_sec == 0) {
3557 		ktime_t kt = ktime_get_real();
3558 		sock_write_timestamp(sk, kt);
3559 		ts = ktime_to_timespec64(kt);
3560 	}
3561 
3562 	if (timeval)
3563 		ts.tv_nsec /= 1000;
3564 
3565 #ifdef CONFIG_COMPAT_32BIT_TIME
3566 	if (time32)
3567 		return put_old_timespec32(&ts, userstamp);
3568 #endif
3569 #ifdef CONFIG_SPARC64
3570 	/* beware of padding in sparc64 timeval */
3571 	if (timeval && !in_compat_syscall()) {
3572 		struct __kernel_old_timeval __user tv = {
3573 			.tv_sec = ts.tv_sec,
3574 			.tv_usec = ts.tv_nsec,
3575 		};
3576 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3577 			return -EFAULT;
3578 		return 0;
3579 	}
3580 #endif
3581 	return put_timespec64(&ts, userstamp);
3582 }
3583 EXPORT_SYMBOL(sock_gettstamp);
3584 
3585 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3586 {
3587 	if (!sock_flag(sk, flag)) {
3588 		unsigned long previous_flags = sk->sk_flags;
3589 
3590 		sock_set_flag(sk, flag);
3591 		/*
3592 		 * we just set one of the two flags which require net
3593 		 * time stamping, but time stamping might have been on
3594 		 * already because of the other one
3595 		 */
3596 		if (sock_needs_netstamp(sk) &&
3597 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3598 			net_enable_timestamp();
3599 	}
3600 }
3601 
3602 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3603 		       int level, int type)
3604 {
3605 	struct sock_exterr_skb *serr;
3606 	struct sk_buff *skb;
3607 	int copied, err;
3608 
3609 	err = -EAGAIN;
3610 	skb = sock_dequeue_err_skb(sk);
3611 	if (skb == NULL)
3612 		goto out;
3613 
3614 	copied = skb->len;
3615 	if (copied > len) {
3616 		msg->msg_flags |= MSG_TRUNC;
3617 		copied = len;
3618 	}
3619 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3620 	if (err)
3621 		goto out_free_skb;
3622 
3623 	sock_recv_timestamp(msg, sk, skb);
3624 
3625 	serr = SKB_EXT_ERR(skb);
3626 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3627 
3628 	msg->msg_flags |= MSG_ERRQUEUE;
3629 	err = copied;
3630 
3631 out_free_skb:
3632 	kfree_skb(skb);
3633 out:
3634 	return err;
3635 }
3636 EXPORT_SYMBOL(sock_recv_errqueue);
3637 
3638 /*
3639  *	Get a socket option on an socket.
3640  *
3641  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3642  *	asynchronous errors should be reported by getsockopt. We assume
3643  *	this means if you specify SO_ERROR (otherwise whats the point of it).
3644  */
3645 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3646 			   char __user *optval, int __user *optlen)
3647 {
3648 	struct sock *sk = sock->sk;
3649 
3650 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3651 	return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3652 }
3653 EXPORT_SYMBOL(sock_common_getsockopt);
3654 
3655 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3656 			int flags)
3657 {
3658 	struct sock *sk = sock->sk;
3659 	int addr_len = 0;
3660 	int err;
3661 
3662 	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3663 	if (err >= 0)
3664 		msg->msg_namelen = addr_len;
3665 	return err;
3666 }
3667 EXPORT_SYMBOL(sock_common_recvmsg);
3668 
3669 /*
3670  *	Set socket options on an inet socket.
3671  */
3672 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3673 			   sockptr_t optval, unsigned int optlen)
3674 {
3675 	struct sock *sk = sock->sk;
3676 
3677 	/* IPV6_ADDRFORM can change sk->sk_prot under us. */
3678 	return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3679 }
3680 EXPORT_SYMBOL(sock_common_setsockopt);
3681 
3682 void sk_common_release(struct sock *sk)
3683 {
3684 	if (sk->sk_prot->destroy)
3685 		sk->sk_prot->destroy(sk);
3686 
3687 	/*
3688 	 * Observation: when sk_common_release is called, processes have
3689 	 * no access to socket. But net still has.
3690 	 * Step one, detach it from networking:
3691 	 *
3692 	 * A. Remove from hash tables.
3693 	 */
3694 
3695 	sk->sk_prot->unhash(sk);
3696 
3697 	/*
3698 	 * In this point socket cannot receive new packets, but it is possible
3699 	 * that some packets are in flight because some CPU runs receiver and
3700 	 * did hash table lookup before we unhashed socket. They will achieve
3701 	 * receive queue and will be purged by socket destructor.
3702 	 *
3703 	 * Also we still have packets pending on receive queue and probably,
3704 	 * our own packets waiting in device queues. sock_destroy will drain
3705 	 * receive queue, but transmitted packets will delay socket destruction
3706 	 * until the last reference will be released.
3707 	 */
3708 
3709 	sock_orphan(sk);
3710 
3711 	xfrm_sk_free_policy(sk);
3712 
3713 	sk_refcnt_debug_release(sk);
3714 
3715 	sock_put(sk);
3716 }
3717 EXPORT_SYMBOL(sk_common_release);
3718 
3719 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3720 {
3721 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3722 
3723 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3724 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3725 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3726 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3727 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3728 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3729 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3730 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3731 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3732 }
3733 
3734 #ifdef CONFIG_PROC_FS
3735 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3736 
3737 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3738 {
3739 	int cpu, idx = prot->inuse_idx;
3740 	int res = 0;
3741 
3742 	for_each_possible_cpu(cpu)
3743 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3744 
3745 	return res >= 0 ? res : 0;
3746 }
3747 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3748 
3749 int sock_inuse_get(struct net *net)
3750 {
3751 	int cpu, res = 0;
3752 
3753 	for_each_possible_cpu(cpu)
3754 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3755 
3756 	return res;
3757 }
3758 
3759 EXPORT_SYMBOL_GPL(sock_inuse_get);
3760 
3761 static int __net_init sock_inuse_init_net(struct net *net)
3762 {
3763 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3764 	if (net->core.prot_inuse == NULL)
3765 		return -ENOMEM;
3766 	return 0;
3767 }
3768 
3769 static void __net_exit sock_inuse_exit_net(struct net *net)
3770 {
3771 	free_percpu(net->core.prot_inuse);
3772 }
3773 
3774 static struct pernet_operations net_inuse_ops = {
3775 	.init = sock_inuse_init_net,
3776 	.exit = sock_inuse_exit_net,
3777 };
3778 
3779 static __init int net_inuse_init(void)
3780 {
3781 	if (register_pernet_subsys(&net_inuse_ops))
3782 		panic("Cannot initialize net inuse counters");
3783 
3784 	return 0;
3785 }
3786 
3787 core_initcall(net_inuse_init);
3788 
3789 static int assign_proto_idx(struct proto *prot)
3790 {
3791 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3792 
3793 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3794 		pr_err("PROTO_INUSE_NR exhausted\n");
3795 		return -ENOSPC;
3796 	}
3797 
3798 	set_bit(prot->inuse_idx, proto_inuse_idx);
3799 	return 0;
3800 }
3801 
3802 static void release_proto_idx(struct proto *prot)
3803 {
3804 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3805 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3806 }
3807 #else
3808 static inline int assign_proto_idx(struct proto *prot)
3809 {
3810 	return 0;
3811 }
3812 
3813 static inline void release_proto_idx(struct proto *prot)
3814 {
3815 }
3816 
3817 #endif
3818 
3819 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3820 {
3821 	if (!twsk_prot)
3822 		return;
3823 	kfree(twsk_prot->twsk_slab_name);
3824 	twsk_prot->twsk_slab_name = NULL;
3825 	kmem_cache_destroy(twsk_prot->twsk_slab);
3826 	twsk_prot->twsk_slab = NULL;
3827 }
3828 
3829 static int tw_prot_init(const struct proto *prot)
3830 {
3831 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3832 
3833 	if (!twsk_prot)
3834 		return 0;
3835 
3836 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3837 					      prot->name);
3838 	if (!twsk_prot->twsk_slab_name)
3839 		return -ENOMEM;
3840 
3841 	twsk_prot->twsk_slab =
3842 		kmem_cache_create(twsk_prot->twsk_slab_name,
3843 				  twsk_prot->twsk_obj_size, 0,
3844 				  SLAB_ACCOUNT | prot->slab_flags,
3845 				  NULL);
3846 	if (!twsk_prot->twsk_slab) {
3847 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3848 			prot->name);
3849 		return -ENOMEM;
3850 	}
3851 
3852 	return 0;
3853 }
3854 
3855 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3856 {
3857 	if (!rsk_prot)
3858 		return;
3859 	kfree(rsk_prot->slab_name);
3860 	rsk_prot->slab_name = NULL;
3861 	kmem_cache_destroy(rsk_prot->slab);
3862 	rsk_prot->slab = NULL;
3863 }
3864 
3865 static int req_prot_init(const struct proto *prot)
3866 {
3867 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3868 
3869 	if (!rsk_prot)
3870 		return 0;
3871 
3872 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3873 					prot->name);
3874 	if (!rsk_prot->slab_name)
3875 		return -ENOMEM;
3876 
3877 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3878 					   rsk_prot->obj_size, 0,
3879 					   SLAB_ACCOUNT | prot->slab_flags,
3880 					   NULL);
3881 
3882 	if (!rsk_prot->slab) {
3883 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3884 			prot->name);
3885 		return -ENOMEM;
3886 	}
3887 	return 0;
3888 }
3889 
3890 int proto_register(struct proto *prot, int alloc_slab)
3891 {
3892 	int ret = -ENOBUFS;
3893 
3894 	if (prot->memory_allocated && !prot->sysctl_mem) {
3895 		pr_err("%s: missing sysctl_mem\n", prot->name);
3896 		return -EINVAL;
3897 	}
3898 	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
3899 		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
3900 		return -EINVAL;
3901 	}
3902 	if (alloc_slab) {
3903 		prot->slab = kmem_cache_create_usercopy(prot->name,
3904 					prot->obj_size, 0,
3905 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3906 					prot->slab_flags,
3907 					prot->useroffset, prot->usersize,
3908 					NULL);
3909 
3910 		if (prot->slab == NULL) {
3911 			pr_crit("%s: Can't create sock SLAB cache!\n",
3912 				prot->name);
3913 			goto out;
3914 		}
3915 
3916 		if (req_prot_init(prot))
3917 			goto out_free_request_sock_slab;
3918 
3919 		if (tw_prot_init(prot))
3920 			goto out_free_timewait_sock_slab;
3921 	}
3922 
3923 	mutex_lock(&proto_list_mutex);
3924 	ret = assign_proto_idx(prot);
3925 	if (ret) {
3926 		mutex_unlock(&proto_list_mutex);
3927 		goto out_free_timewait_sock_slab;
3928 	}
3929 	list_add(&prot->node, &proto_list);
3930 	mutex_unlock(&proto_list_mutex);
3931 	return ret;
3932 
3933 out_free_timewait_sock_slab:
3934 	if (alloc_slab)
3935 		tw_prot_cleanup(prot->twsk_prot);
3936 out_free_request_sock_slab:
3937 	if (alloc_slab) {
3938 		req_prot_cleanup(prot->rsk_prot);
3939 
3940 		kmem_cache_destroy(prot->slab);
3941 		prot->slab = NULL;
3942 	}
3943 out:
3944 	return ret;
3945 }
3946 EXPORT_SYMBOL(proto_register);
3947 
3948 void proto_unregister(struct proto *prot)
3949 {
3950 	mutex_lock(&proto_list_mutex);
3951 	release_proto_idx(prot);
3952 	list_del(&prot->node);
3953 	mutex_unlock(&proto_list_mutex);
3954 
3955 	kmem_cache_destroy(prot->slab);
3956 	prot->slab = NULL;
3957 
3958 	req_prot_cleanup(prot->rsk_prot);
3959 	tw_prot_cleanup(prot->twsk_prot);
3960 }
3961 EXPORT_SYMBOL(proto_unregister);
3962 
3963 int sock_load_diag_module(int family, int protocol)
3964 {
3965 	if (!protocol) {
3966 		if (!sock_is_registered(family))
3967 			return -ENOENT;
3968 
3969 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3970 				      NETLINK_SOCK_DIAG, family);
3971 	}
3972 
3973 #ifdef CONFIG_INET
3974 	if (family == AF_INET &&
3975 	    protocol != IPPROTO_RAW &&
3976 	    protocol < MAX_INET_PROTOS &&
3977 	    !rcu_access_pointer(inet_protos[protocol]))
3978 		return -ENOENT;
3979 #endif
3980 
3981 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3982 			      NETLINK_SOCK_DIAG, family, protocol);
3983 }
3984 EXPORT_SYMBOL(sock_load_diag_module);
3985 
3986 #ifdef CONFIG_PROC_FS
3987 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3988 	__acquires(proto_list_mutex)
3989 {
3990 	mutex_lock(&proto_list_mutex);
3991 	return seq_list_start_head(&proto_list, *pos);
3992 }
3993 
3994 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3995 {
3996 	return seq_list_next(v, &proto_list, pos);
3997 }
3998 
3999 static void proto_seq_stop(struct seq_file *seq, void *v)
4000 	__releases(proto_list_mutex)
4001 {
4002 	mutex_unlock(&proto_list_mutex);
4003 }
4004 
4005 static char proto_method_implemented(const void *method)
4006 {
4007 	return method == NULL ? 'n' : 'y';
4008 }
4009 static long sock_prot_memory_allocated(struct proto *proto)
4010 {
4011 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4012 }
4013 
4014 static const char *sock_prot_memory_pressure(struct proto *proto)
4015 {
4016 	return proto->memory_pressure != NULL ?
4017 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4018 }
4019 
4020 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4021 {
4022 
4023 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
4024 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4025 		   proto->name,
4026 		   proto->obj_size,
4027 		   sock_prot_inuse_get(seq_file_net(seq), proto),
4028 		   sock_prot_memory_allocated(proto),
4029 		   sock_prot_memory_pressure(proto),
4030 		   proto->max_header,
4031 		   proto->slab == NULL ? "no" : "yes",
4032 		   module_name(proto->owner),
4033 		   proto_method_implemented(proto->close),
4034 		   proto_method_implemented(proto->connect),
4035 		   proto_method_implemented(proto->disconnect),
4036 		   proto_method_implemented(proto->accept),
4037 		   proto_method_implemented(proto->ioctl),
4038 		   proto_method_implemented(proto->init),
4039 		   proto_method_implemented(proto->destroy),
4040 		   proto_method_implemented(proto->shutdown),
4041 		   proto_method_implemented(proto->setsockopt),
4042 		   proto_method_implemented(proto->getsockopt),
4043 		   proto_method_implemented(proto->sendmsg),
4044 		   proto_method_implemented(proto->recvmsg),
4045 		   proto_method_implemented(proto->sendpage),
4046 		   proto_method_implemented(proto->bind),
4047 		   proto_method_implemented(proto->backlog_rcv),
4048 		   proto_method_implemented(proto->hash),
4049 		   proto_method_implemented(proto->unhash),
4050 		   proto_method_implemented(proto->get_port),
4051 		   proto_method_implemented(proto->enter_memory_pressure));
4052 }
4053 
4054 static int proto_seq_show(struct seq_file *seq, void *v)
4055 {
4056 	if (v == &proto_list)
4057 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4058 			   "protocol",
4059 			   "size",
4060 			   "sockets",
4061 			   "memory",
4062 			   "press",
4063 			   "maxhdr",
4064 			   "slab",
4065 			   "module",
4066 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
4067 	else
4068 		proto_seq_printf(seq, list_entry(v, struct proto, node));
4069 	return 0;
4070 }
4071 
4072 static const struct seq_operations proto_seq_ops = {
4073 	.start  = proto_seq_start,
4074 	.next   = proto_seq_next,
4075 	.stop   = proto_seq_stop,
4076 	.show   = proto_seq_show,
4077 };
4078 
4079 static __net_init int proto_init_net(struct net *net)
4080 {
4081 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4082 			sizeof(struct seq_net_private)))
4083 		return -ENOMEM;
4084 
4085 	return 0;
4086 }
4087 
4088 static __net_exit void proto_exit_net(struct net *net)
4089 {
4090 	remove_proc_entry("protocols", net->proc_net);
4091 }
4092 
4093 
4094 static __net_initdata struct pernet_operations proto_net_ops = {
4095 	.init = proto_init_net,
4096 	.exit = proto_exit_net,
4097 };
4098 
4099 static int __init proto_init(void)
4100 {
4101 	return register_pernet_subsys(&proto_net_ops);
4102 }
4103 
4104 subsys_initcall(proto_init);
4105 
4106 #endif /* PROC_FS */
4107 
4108 #ifdef CONFIG_NET_RX_BUSY_POLL
4109 bool sk_busy_loop_end(void *p, unsigned long start_time)
4110 {
4111 	struct sock *sk = p;
4112 
4113 	return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
4114 	       sk_busy_loop_timeout(sk, start_time);
4115 }
4116 EXPORT_SYMBOL(sk_busy_loop_end);
4117 #endif /* CONFIG_NET_RX_BUSY_POLL */
4118 
4119 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4120 {
4121 	if (!sk->sk_prot->bind_add)
4122 		return -EOPNOTSUPP;
4123 	return sk->sk_prot->bind_add(sk, addr, addr_len);
4124 }
4125 EXPORT_SYMBOL(sock_bind_add);
4126