xref: /openbmc/linux/net/core/sock.c (revision f80be457)
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 	return sock_bindtoindex(sk, index, true);
707 out:
708 #endif
709 
710 	return ret;
711 }
712 
713 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
714 				int __user *optlen, int len)
715 {
716 	int ret = -ENOPROTOOPT;
717 #ifdef CONFIG_NETDEVICES
718 	int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
719 	struct net *net = sock_net(sk);
720 	char devname[IFNAMSIZ];
721 
722 	if (bound_dev_if == 0) {
723 		len = 0;
724 		goto zero;
725 	}
726 
727 	ret = -EINVAL;
728 	if (len < IFNAMSIZ)
729 		goto out;
730 
731 	ret = netdev_get_name(net, devname, bound_dev_if);
732 	if (ret)
733 		goto out;
734 
735 	len = strlen(devname) + 1;
736 
737 	ret = -EFAULT;
738 	if (copy_to_user(optval, devname, len))
739 		goto out;
740 
741 zero:
742 	ret = -EFAULT;
743 	if (put_user(len, optlen))
744 		goto out;
745 
746 	ret = 0;
747 
748 out:
749 #endif
750 
751 	return ret;
752 }
753 
754 bool sk_mc_loop(struct sock *sk)
755 {
756 	if (dev_recursion_level())
757 		return false;
758 	if (!sk)
759 		return true;
760 	switch (sk->sk_family) {
761 	case AF_INET:
762 		return inet_sk(sk)->mc_loop;
763 #if IS_ENABLED(CONFIG_IPV6)
764 	case AF_INET6:
765 		return inet6_sk(sk)->mc_loop;
766 #endif
767 	}
768 	WARN_ON_ONCE(1);
769 	return true;
770 }
771 EXPORT_SYMBOL(sk_mc_loop);
772 
773 void sock_set_reuseaddr(struct sock *sk)
774 {
775 	lock_sock(sk);
776 	sk->sk_reuse = SK_CAN_REUSE;
777 	release_sock(sk);
778 }
779 EXPORT_SYMBOL(sock_set_reuseaddr);
780 
781 void sock_set_reuseport(struct sock *sk)
782 {
783 	lock_sock(sk);
784 	sk->sk_reuseport = true;
785 	release_sock(sk);
786 }
787 EXPORT_SYMBOL(sock_set_reuseport);
788 
789 void sock_no_linger(struct sock *sk)
790 {
791 	lock_sock(sk);
792 	sk->sk_lingertime = 0;
793 	sock_set_flag(sk, SOCK_LINGER);
794 	release_sock(sk);
795 }
796 EXPORT_SYMBOL(sock_no_linger);
797 
798 void sock_set_priority(struct sock *sk, u32 priority)
799 {
800 	lock_sock(sk);
801 	sk->sk_priority = priority;
802 	release_sock(sk);
803 }
804 EXPORT_SYMBOL(sock_set_priority);
805 
806 void sock_set_sndtimeo(struct sock *sk, s64 secs)
807 {
808 	lock_sock(sk);
809 	if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
810 		sk->sk_sndtimeo = secs * HZ;
811 	else
812 		sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
813 	release_sock(sk);
814 }
815 EXPORT_SYMBOL(sock_set_sndtimeo);
816 
817 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
818 {
819 	if (val)  {
820 		sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
821 		sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
822 		sock_set_flag(sk, SOCK_RCVTSTAMP);
823 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
824 	} else {
825 		sock_reset_flag(sk, SOCK_RCVTSTAMP);
826 		sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
827 	}
828 }
829 
830 void sock_enable_timestamps(struct sock *sk)
831 {
832 	lock_sock(sk);
833 	__sock_set_timestamps(sk, true, false, true);
834 	release_sock(sk);
835 }
836 EXPORT_SYMBOL(sock_enable_timestamps);
837 
838 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
839 {
840 	switch (optname) {
841 	case SO_TIMESTAMP_OLD:
842 		__sock_set_timestamps(sk, valbool, false, false);
843 		break;
844 	case SO_TIMESTAMP_NEW:
845 		__sock_set_timestamps(sk, valbool, true, false);
846 		break;
847 	case SO_TIMESTAMPNS_OLD:
848 		__sock_set_timestamps(sk, valbool, false, true);
849 		break;
850 	case SO_TIMESTAMPNS_NEW:
851 		__sock_set_timestamps(sk, valbool, true, true);
852 		break;
853 	}
854 }
855 
856 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
857 {
858 	struct net *net = sock_net(sk);
859 	struct net_device *dev = NULL;
860 	bool match = false;
861 	int *vclock_index;
862 	int i, num;
863 
864 	if (sk->sk_bound_dev_if)
865 		dev = dev_get_by_index(net, sk->sk_bound_dev_if);
866 
867 	if (!dev) {
868 		pr_err("%s: sock not bind to device\n", __func__);
869 		return -EOPNOTSUPP;
870 	}
871 
872 	num = ethtool_get_phc_vclocks(dev, &vclock_index);
873 	dev_put(dev);
874 
875 	for (i = 0; i < num; i++) {
876 		if (*(vclock_index + i) == phc_index) {
877 			match = true;
878 			break;
879 		}
880 	}
881 
882 	if (num > 0)
883 		kfree(vclock_index);
884 
885 	if (!match)
886 		return -EINVAL;
887 
888 	sk->sk_bind_phc = phc_index;
889 
890 	return 0;
891 }
892 
893 int sock_set_timestamping(struct sock *sk, int optname,
894 			  struct so_timestamping timestamping)
895 {
896 	int val = timestamping.flags;
897 	int ret;
898 
899 	if (val & ~SOF_TIMESTAMPING_MASK)
900 		return -EINVAL;
901 
902 	if (val & SOF_TIMESTAMPING_OPT_ID &&
903 	    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
904 		if (sk_is_tcp(sk)) {
905 			if ((1 << sk->sk_state) &
906 			    (TCPF_CLOSE | TCPF_LISTEN))
907 				return -EINVAL;
908 			atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
909 		} else {
910 			atomic_set(&sk->sk_tskey, 0);
911 		}
912 	}
913 
914 	if (val & SOF_TIMESTAMPING_OPT_STATS &&
915 	    !(val & SOF_TIMESTAMPING_OPT_TSONLY))
916 		return -EINVAL;
917 
918 	if (val & SOF_TIMESTAMPING_BIND_PHC) {
919 		ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
920 		if (ret)
921 			return ret;
922 	}
923 
924 	sk->sk_tsflags = val;
925 	sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
926 
927 	if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
928 		sock_enable_timestamp(sk,
929 				      SOCK_TIMESTAMPING_RX_SOFTWARE);
930 	else
931 		sock_disable_timestamp(sk,
932 				       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
933 	return 0;
934 }
935 
936 void sock_set_keepalive(struct sock *sk)
937 {
938 	lock_sock(sk);
939 	if (sk->sk_prot->keepalive)
940 		sk->sk_prot->keepalive(sk, true);
941 	sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
942 	release_sock(sk);
943 }
944 EXPORT_SYMBOL(sock_set_keepalive);
945 
946 static void __sock_set_rcvbuf(struct sock *sk, int val)
947 {
948 	/* Ensure val * 2 fits into an int, to prevent max_t() from treating it
949 	 * as a negative value.
950 	 */
951 	val = min_t(int, val, INT_MAX / 2);
952 	sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
953 
954 	/* We double it on the way in to account for "struct sk_buff" etc.
955 	 * overhead.   Applications assume that the SO_RCVBUF setting they make
956 	 * will allow that much actual data to be received on that socket.
957 	 *
958 	 * Applications are unaware that "struct sk_buff" and other overheads
959 	 * allocate from the receive buffer during socket buffer allocation.
960 	 *
961 	 * And after considering the possible alternatives, returning the value
962 	 * we actually used in getsockopt is the most desirable behavior.
963 	 */
964 	WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
965 }
966 
967 void sock_set_rcvbuf(struct sock *sk, int val)
968 {
969 	lock_sock(sk);
970 	__sock_set_rcvbuf(sk, val);
971 	release_sock(sk);
972 }
973 EXPORT_SYMBOL(sock_set_rcvbuf);
974 
975 static void __sock_set_mark(struct sock *sk, u32 val)
976 {
977 	if (val != sk->sk_mark) {
978 		sk->sk_mark = val;
979 		sk_dst_reset(sk);
980 	}
981 }
982 
983 void sock_set_mark(struct sock *sk, u32 val)
984 {
985 	lock_sock(sk);
986 	__sock_set_mark(sk, val);
987 	release_sock(sk);
988 }
989 EXPORT_SYMBOL(sock_set_mark);
990 
991 static void sock_release_reserved_memory(struct sock *sk, int bytes)
992 {
993 	/* Round down bytes to multiple of pages */
994 	bytes = round_down(bytes, PAGE_SIZE);
995 
996 	WARN_ON(bytes > sk->sk_reserved_mem);
997 	sk->sk_reserved_mem -= bytes;
998 	sk_mem_reclaim(sk);
999 }
1000 
1001 static int sock_reserve_memory(struct sock *sk, int bytes)
1002 {
1003 	long allocated;
1004 	bool charged;
1005 	int pages;
1006 
1007 	if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1008 		return -EOPNOTSUPP;
1009 
1010 	if (!bytes)
1011 		return 0;
1012 
1013 	pages = sk_mem_pages(bytes);
1014 
1015 	/* pre-charge to memcg */
1016 	charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1017 					  GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1018 	if (!charged)
1019 		return -ENOMEM;
1020 
1021 	/* pre-charge to forward_alloc */
1022 	sk_memory_allocated_add(sk, pages);
1023 	allocated = sk_memory_allocated(sk);
1024 	/* If the system goes into memory pressure with this
1025 	 * precharge, give up and return error.
1026 	 */
1027 	if (allocated > sk_prot_mem_limits(sk, 1)) {
1028 		sk_memory_allocated_sub(sk, pages);
1029 		mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1030 		return -ENOMEM;
1031 	}
1032 	sk->sk_forward_alloc += pages << PAGE_SHIFT;
1033 
1034 	sk->sk_reserved_mem += pages << PAGE_SHIFT;
1035 
1036 	return 0;
1037 }
1038 
1039 /*
1040  *	This is meant for all protocols to use and covers goings on
1041  *	at the socket level. Everything here is generic.
1042  */
1043 
1044 int sock_setsockopt(struct socket *sock, int level, int optname,
1045 		    sockptr_t optval, unsigned int optlen)
1046 {
1047 	struct so_timestamping timestamping;
1048 	struct sock_txtime sk_txtime;
1049 	struct sock *sk = sock->sk;
1050 	int val;
1051 	int valbool;
1052 	struct linger ling;
1053 	int ret = 0;
1054 
1055 	/*
1056 	 *	Options without arguments
1057 	 */
1058 
1059 	if (optname == SO_BINDTODEVICE)
1060 		return sock_setbindtodevice(sk, optval, optlen);
1061 
1062 	if (optlen < sizeof(int))
1063 		return -EINVAL;
1064 
1065 	if (copy_from_sockptr(&val, optval, sizeof(val)))
1066 		return -EFAULT;
1067 
1068 	valbool = val ? 1 : 0;
1069 
1070 	lock_sock(sk);
1071 
1072 	switch (optname) {
1073 	case SO_DEBUG:
1074 		if (val && !capable(CAP_NET_ADMIN))
1075 			ret = -EACCES;
1076 		else
1077 			sock_valbool_flag(sk, SOCK_DBG, valbool);
1078 		break;
1079 	case SO_REUSEADDR:
1080 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1081 		break;
1082 	case SO_REUSEPORT:
1083 		sk->sk_reuseport = valbool;
1084 		break;
1085 	case SO_TYPE:
1086 	case SO_PROTOCOL:
1087 	case SO_DOMAIN:
1088 	case SO_ERROR:
1089 		ret = -ENOPROTOOPT;
1090 		break;
1091 	case SO_DONTROUTE:
1092 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1093 		sk_dst_reset(sk);
1094 		break;
1095 	case SO_BROADCAST:
1096 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1097 		break;
1098 	case SO_SNDBUF:
1099 		/* Don't error on this BSD doesn't and if you think
1100 		 * about it this is right. Otherwise apps have to
1101 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1102 		 * are treated in BSD as hints
1103 		 */
1104 		val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1105 set_sndbuf:
1106 		/* Ensure val * 2 fits into an int, to prevent max_t()
1107 		 * from treating it as a negative value.
1108 		 */
1109 		val = min_t(int, val, INT_MAX / 2);
1110 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1111 		WRITE_ONCE(sk->sk_sndbuf,
1112 			   max_t(int, val * 2, SOCK_MIN_SNDBUF));
1113 		/* Wake up sending tasks if we upped the value. */
1114 		sk->sk_write_space(sk);
1115 		break;
1116 
1117 	case SO_SNDBUFFORCE:
1118 		if (!capable(CAP_NET_ADMIN)) {
1119 			ret = -EPERM;
1120 			break;
1121 		}
1122 
1123 		/* No negative values (to prevent underflow, as val will be
1124 		 * multiplied by 2).
1125 		 */
1126 		if (val < 0)
1127 			val = 0;
1128 		goto set_sndbuf;
1129 
1130 	case SO_RCVBUF:
1131 		/* Don't error on this BSD doesn't and if you think
1132 		 * about it this is right. Otherwise apps have to
1133 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1134 		 * are treated in BSD as hints
1135 		 */
1136 		__sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1137 		break;
1138 
1139 	case SO_RCVBUFFORCE:
1140 		if (!capable(CAP_NET_ADMIN)) {
1141 			ret = -EPERM;
1142 			break;
1143 		}
1144 
1145 		/* No negative values (to prevent underflow, as val will be
1146 		 * multiplied by 2).
1147 		 */
1148 		__sock_set_rcvbuf(sk, max(val, 0));
1149 		break;
1150 
1151 	case SO_KEEPALIVE:
1152 		if (sk->sk_prot->keepalive)
1153 			sk->sk_prot->keepalive(sk, valbool);
1154 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1155 		break;
1156 
1157 	case SO_OOBINLINE:
1158 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1159 		break;
1160 
1161 	case SO_NO_CHECK:
1162 		sk->sk_no_check_tx = valbool;
1163 		break;
1164 
1165 	case SO_PRIORITY:
1166 		if ((val >= 0 && val <= 6) ||
1167 		    ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1168 		    ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1169 			sk->sk_priority = val;
1170 		else
1171 			ret = -EPERM;
1172 		break;
1173 
1174 	case SO_LINGER:
1175 		if (optlen < sizeof(ling)) {
1176 			ret = -EINVAL;	/* 1003.1g */
1177 			break;
1178 		}
1179 		if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1180 			ret = -EFAULT;
1181 			break;
1182 		}
1183 		if (!ling.l_onoff)
1184 			sock_reset_flag(sk, SOCK_LINGER);
1185 		else {
1186 #if (BITS_PER_LONG == 32)
1187 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
1188 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
1189 			else
1190 #endif
1191 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
1192 			sock_set_flag(sk, SOCK_LINGER);
1193 		}
1194 		break;
1195 
1196 	case SO_BSDCOMPAT:
1197 		break;
1198 
1199 	case SO_PASSCRED:
1200 		if (valbool)
1201 			set_bit(SOCK_PASSCRED, &sock->flags);
1202 		else
1203 			clear_bit(SOCK_PASSCRED, &sock->flags);
1204 		break;
1205 
1206 	case SO_TIMESTAMP_OLD:
1207 	case SO_TIMESTAMP_NEW:
1208 	case SO_TIMESTAMPNS_OLD:
1209 	case SO_TIMESTAMPNS_NEW:
1210 		sock_set_timestamp(sk, optname, valbool);
1211 		break;
1212 
1213 	case SO_TIMESTAMPING_NEW:
1214 	case SO_TIMESTAMPING_OLD:
1215 		if (optlen == sizeof(timestamping)) {
1216 			if (copy_from_sockptr(&timestamping, optval,
1217 					      sizeof(timestamping))) {
1218 				ret = -EFAULT;
1219 				break;
1220 			}
1221 		} else {
1222 			memset(&timestamping, 0, sizeof(timestamping));
1223 			timestamping.flags = val;
1224 		}
1225 		ret = sock_set_timestamping(sk, optname, timestamping);
1226 		break;
1227 
1228 	case SO_RCVLOWAT:
1229 		if (val < 0)
1230 			val = INT_MAX;
1231 		if (sock->ops->set_rcvlowat)
1232 			ret = sock->ops->set_rcvlowat(sk, val);
1233 		else
1234 			WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1235 		break;
1236 
1237 	case SO_RCVTIMEO_OLD:
1238 	case SO_RCVTIMEO_NEW:
1239 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1240 				       optlen, optname == SO_RCVTIMEO_OLD);
1241 		break;
1242 
1243 	case SO_SNDTIMEO_OLD:
1244 	case SO_SNDTIMEO_NEW:
1245 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1246 				       optlen, optname == SO_SNDTIMEO_OLD);
1247 		break;
1248 
1249 	case SO_ATTACH_FILTER: {
1250 		struct sock_fprog fprog;
1251 
1252 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1253 		if (!ret)
1254 			ret = sk_attach_filter(&fprog, sk);
1255 		break;
1256 	}
1257 	case SO_ATTACH_BPF:
1258 		ret = -EINVAL;
1259 		if (optlen == sizeof(u32)) {
1260 			u32 ufd;
1261 
1262 			ret = -EFAULT;
1263 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1264 				break;
1265 
1266 			ret = sk_attach_bpf(ufd, sk);
1267 		}
1268 		break;
1269 
1270 	case SO_ATTACH_REUSEPORT_CBPF: {
1271 		struct sock_fprog fprog;
1272 
1273 		ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1274 		if (!ret)
1275 			ret = sk_reuseport_attach_filter(&fprog, sk);
1276 		break;
1277 	}
1278 	case SO_ATTACH_REUSEPORT_EBPF:
1279 		ret = -EINVAL;
1280 		if (optlen == sizeof(u32)) {
1281 			u32 ufd;
1282 
1283 			ret = -EFAULT;
1284 			if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1285 				break;
1286 
1287 			ret = sk_reuseport_attach_bpf(ufd, sk);
1288 		}
1289 		break;
1290 
1291 	case SO_DETACH_REUSEPORT_BPF:
1292 		ret = reuseport_detach_prog(sk);
1293 		break;
1294 
1295 	case SO_DETACH_FILTER:
1296 		ret = sk_detach_filter(sk);
1297 		break;
1298 
1299 	case SO_LOCK_FILTER:
1300 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1301 			ret = -EPERM;
1302 		else
1303 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1304 		break;
1305 
1306 	case SO_PASSSEC:
1307 		if (valbool)
1308 			set_bit(SOCK_PASSSEC, &sock->flags);
1309 		else
1310 			clear_bit(SOCK_PASSSEC, &sock->flags);
1311 		break;
1312 	case SO_MARK:
1313 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1314 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1315 			ret = -EPERM;
1316 			break;
1317 		}
1318 
1319 		__sock_set_mark(sk, val);
1320 		break;
1321 	case SO_RCVMARK:
1322 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1323 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1324 			ret = -EPERM;
1325 			break;
1326 		}
1327 
1328 		sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1329 		break;
1330 
1331 	case SO_RXQ_OVFL:
1332 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1333 		break;
1334 
1335 	case SO_WIFI_STATUS:
1336 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1337 		break;
1338 
1339 	case SO_PEEK_OFF:
1340 		if (sock->ops->set_peek_off)
1341 			ret = sock->ops->set_peek_off(sk, val);
1342 		else
1343 			ret = -EOPNOTSUPP;
1344 		break;
1345 
1346 	case SO_NOFCS:
1347 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1348 		break;
1349 
1350 	case SO_SELECT_ERR_QUEUE:
1351 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1352 		break;
1353 
1354 #ifdef CONFIG_NET_RX_BUSY_POLL
1355 	case SO_BUSY_POLL:
1356 		/* allow unprivileged users to decrease the value */
1357 		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1358 			ret = -EPERM;
1359 		else {
1360 			if (val < 0)
1361 				ret = -EINVAL;
1362 			else
1363 				WRITE_ONCE(sk->sk_ll_usec, val);
1364 		}
1365 		break;
1366 	case SO_PREFER_BUSY_POLL:
1367 		if (valbool && !capable(CAP_NET_ADMIN))
1368 			ret = -EPERM;
1369 		else
1370 			WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1371 		break;
1372 	case SO_BUSY_POLL_BUDGET:
1373 		if (val > READ_ONCE(sk->sk_busy_poll_budget) && !capable(CAP_NET_ADMIN)) {
1374 			ret = -EPERM;
1375 		} else {
1376 			if (val < 0 || val > U16_MAX)
1377 				ret = -EINVAL;
1378 			else
1379 				WRITE_ONCE(sk->sk_busy_poll_budget, val);
1380 		}
1381 		break;
1382 #endif
1383 
1384 	case SO_MAX_PACING_RATE:
1385 		{
1386 		unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1387 
1388 		if (sizeof(ulval) != sizeof(val) &&
1389 		    optlen >= sizeof(ulval) &&
1390 		    copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1391 			ret = -EFAULT;
1392 			break;
1393 		}
1394 		if (ulval != ~0UL)
1395 			cmpxchg(&sk->sk_pacing_status,
1396 				SK_PACING_NONE,
1397 				SK_PACING_NEEDED);
1398 		sk->sk_max_pacing_rate = ulval;
1399 		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1400 		break;
1401 		}
1402 	case SO_INCOMING_CPU:
1403 		WRITE_ONCE(sk->sk_incoming_cpu, val);
1404 		break;
1405 
1406 	case SO_CNX_ADVICE:
1407 		if (val == 1)
1408 			dst_negative_advice(sk);
1409 		break;
1410 
1411 	case SO_ZEROCOPY:
1412 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1413 			if (!(sk_is_tcp(sk) ||
1414 			      (sk->sk_type == SOCK_DGRAM &&
1415 			       sk->sk_protocol == IPPROTO_UDP)))
1416 				ret = -EOPNOTSUPP;
1417 		} else if (sk->sk_family != PF_RDS) {
1418 			ret = -EOPNOTSUPP;
1419 		}
1420 		if (!ret) {
1421 			if (val < 0 || val > 1)
1422 				ret = -EINVAL;
1423 			else
1424 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1425 		}
1426 		break;
1427 
1428 	case SO_TXTIME:
1429 		if (optlen != sizeof(struct sock_txtime)) {
1430 			ret = -EINVAL;
1431 			break;
1432 		} else if (copy_from_sockptr(&sk_txtime, optval,
1433 			   sizeof(struct sock_txtime))) {
1434 			ret = -EFAULT;
1435 			break;
1436 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1437 			ret = -EINVAL;
1438 			break;
1439 		}
1440 		/* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1441 		 * scheduler has enough safe guards.
1442 		 */
1443 		if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1444 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1445 			ret = -EPERM;
1446 			break;
1447 		}
1448 		sock_valbool_flag(sk, SOCK_TXTIME, true);
1449 		sk->sk_clockid = sk_txtime.clockid;
1450 		sk->sk_txtime_deadline_mode =
1451 			!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1452 		sk->sk_txtime_report_errors =
1453 			!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1454 		break;
1455 
1456 	case SO_BINDTOIFINDEX:
1457 		ret = sock_bindtoindex_locked(sk, val);
1458 		break;
1459 
1460 	case SO_BUF_LOCK:
1461 		if (val & ~SOCK_BUF_LOCK_MASK) {
1462 			ret = -EINVAL;
1463 			break;
1464 		}
1465 		sk->sk_userlocks = val | (sk->sk_userlocks &
1466 					  ~SOCK_BUF_LOCK_MASK);
1467 		break;
1468 
1469 	case SO_RESERVE_MEM:
1470 	{
1471 		int delta;
1472 
1473 		if (val < 0) {
1474 			ret = -EINVAL;
1475 			break;
1476 		}
1477 
1478 		delta = val - sk->sk_reserved_mem;
1479 		if (delta < 0)
1480 			sock_release_reserved_memory(sk, -delta);
1481 		else
1482 			ret = sock_reserve_memory(sk, delta);
1483 		break;
1484 	}
1485 
1486 	case SO_TXREHASH:
1487 		if (val < -1 || val > 1) {
1488 			ret = -EINVAL;
1489 			break;
1490 		}
1491 		/* Paired with READ_ONCE() in tcp_rtx_synack() */
1492 		WRITE_ONCE(sk->sk_txrehash, (u8)val);
1493 		break;
1494 
1495 	default:
1496 		ret = -ENOPROTOOPT;
1497 		break;
1498 	}
1499 	release_sock(sk);
1500 	return ret;
1501 }
1502 EXPORT_SYMBOL(sock_setsockopt);
1503 
1504 static const struct cred *sk_get_peer_cred(struct sock *sk)
1505 {
1506 	const struct cred *cred;
1507 
1508 	spin_lock(&sk->sk_peer_lock);
1509 	cred = get_cred(sk->sk_peer_cred);
1510 	spin_unlock(&sk->sk_peer_lock);
1511 
1512 	return cred;
1513 }
1514 
1515 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1516 			  struct ucred *ucred)
1517 {
1518 	ucred->pid = pid_vnr(pid);
1519 	ucred->uid = ucred->gid = -1;
1520 	if (cred) {
1521 		struct user_namespace *current_ns = current_user_ns();
1522 
1523 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1524 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1525 	}
1526 }
1527 
1528 static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1529 {
1530 	struct user_namespace *user_ns = current_user_ns();
1531 	int i;
1532 
1533 	for (i = 0; i < src->ngroups; i++)
1534 		if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1535 			return -EFAULT;
1536 
1537 	return 0;
1538 }
1539 
1540 int sock_getsockopt(struct socket *sock, int level, int optname,
1541 		    char __user *optval, int __user *optlen)
1542 {
1543 	struct sock *sk = sock->sk;
1544 
1545 	union {
1546 		int val;
1547 		u64 val64;
1548 		unsigned long ulval;
1549 		struct linger ling;
1550 		struct old_timeval32 tm32;
1551 		struct __kernel_old_timeval tm;
1552 		struct  __kernel_sock_timeval stm;
1553 		struct sock_txtime txtime;
1554 		struct so_timestamping timestamping;
1555 	} v;
1556 
1557 	int lv = sizeof(int);
1558 	int len;
1559 
1560 	if (get_user(len, optlen))
1561 		return -EFAULT;
1562 	if (len < 0)
1563 		return -EINVAL;
1564 
1565 	memset(&v, 0, sizeof(v));
1566 
1567 	switch (optname) {
1568 	case SO_DEBUG:
1569 		v.val = sock_flag(sk, SOCK_DBG);
1570 		break;
1571 
1572 	case SO_DONTROUTE:
1573 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1574 		break;
1575 
1576 	case SO_BROADCAST:
1577 		v.val = sock_flag(sk, SOCK_BROADCAST);
1578 		break;
1579 
1580 	case SO_SNDBUF:
1581 		v.val = sk->sk_sndbuf;
1582 		break;
1583 
1584 	case SO_RCVBUF:
1585 		v.val = sk->sk_rcvbuf;
1586 		break;
1587 
1588 	case SO_REUSEADDR:
1589 		v.val = sk->sk_reuse;
1590 		break;
1591 
1592 	case SO_REUSEPORT:
1593 		v.val = sk->sk_reuseport;
1594 		break;
1595 
1596 	case SO_KEEPALIVE:
1597 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1598 		break;
1599 
1600 	case SO_TYPE:
1601 		v.val = sk->sk_type;
1602 		break;
1603 
1604 	case SO_PROTOCOL:
1605 		v.val = sk->sk_protocol;
1606 		break;
1607 
1608 	case SO_DOMAIN:
1609 		v.val = sk->sk_family;
1610 		break;
1611 
1612 	case SO_ERROR:
1613 		v.val = -sock_error(sk);
1614 		if (v.val == 0)
1615 			v.val = xchg(&sk->sk_err_soft, 0);
1616 		break;
1617 
1618 	case SO_OOBINLINE:
1619 		v.val = sock_flag(sk, SOCK_URGINLINE);
1620 		break;
1621 
1622 	case SO_NO_CHECK:
1623 		v.val = sk->sk_no_check_tx;
1624 		break;
1625 
1626 	case SO_PRIORITY:
1627 		v.val = sk->sk_priority;
1628 		break;
1629 
1630 	case SO_LINGER:
1631 		lv		= sizeof(v.ling);
1632 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1633 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1634 		break;
1635 
1636 	case SO_BSDCOMPAT:
1637 		break;
1638 
1639 	case SO_TIMESTAMP_OLD:
1640 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1641 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1642 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1643 		break;
1644 
1645 	case SO_TIMESTAMPNS_OLD:
1646 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1647 		break;
1648 
1649 	case SO_TIMESTAMP_NEW:
1650 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1651 		break;
1652 
1653 	case SO_TIMESTAMPNS_NEW:
1654 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1655 		break;
1656 
1657 	case SO_TIMESTAMPING_OLD:
1658 		lv = sizeof(v.timestamping);
1659 		v.timestamping.flags = sk->sk_tsflags;
1660 		v.timestamping.bind_phc = sk->sk_bind_phc;
1661 		break;
1662 
1663 	case SO_RCVTIMEO_OLD:
1664 	case SO_RCVTIMEO_NEW:
1665 		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1666 		break;
1667 
1668 	case SO_SNDTIMEO_OLD:
1669 	case SO_SNDTIMEO_NEW:
1670 		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1671 		break;
1672 
1673 	case SO_RCVLOWAT:
1674 		v.val = sk->sk_rcvlowat;
1675 		break;
1676 
1677 	case SO_SNDLOWAT:
1678 		v.val = 1;
1679 		break;
1680 
1681 	case SO_PASSCRED:
1682 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1683 		break;
1684 
1685 	case SO_PEERCRED:
1686 	{
1687 		struct ucred peercred;
1688 		if (len > sizeof(peercred))
1689 			len = sizeof(peercred);
1690 
1691 		spin_lock(&sk->sk_peer_lock);
1692 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1693 		spin_unlock(&sk->sk_peer_lock);
1694 
1695 		if (copy_to_user(optval, &peercred, len))
1696 			return -EFAULT;
1697 		goto lenout;
1698 	}
1699 
1700 	case SO_PEERGROUPS:
1701 	{
1702 		const struct cred *cred;
1703 		int ret, n;
1704 
1705 		cred = sk_get_peer_cred(sk);
1706 		if (!cred)
1707 			return -ENODATA;
1708 
1709 		n = cred->group_info->ngroups;
1710 		if (len < n * sizeof(gid_t)) {
1711 			len = n * sizeof(gid_t);
1712 			put_cred(cred);
1713 			return put_user(len, optlen) ? -EFAULT : -ERANGE;
1714 		}
1715 		len = n * sizeof(gid_t);
1716 
1717 		ret = groups_to_user((gid_t __user *)optval, cred->group_info);
1718 		put_cred(cred);
1719 		if (ret)
1720 			return ret;
1721 		goto lenout;
1722 	}
1723 
1724 	case SO_PEERNAME:
1725 	{
1726 		char address[128];
1727 
1728 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1729 		if (lv < 0)
1730 			return -ENOTCONN;
1731 		if (lv < len)
1732 			return -EINVAL;
1733 		if (copy_to_user(optval, address, len))
1734 			return -EFAULT;
1735 		goto lenout;
1736 	}
1737 
1738 	/* Dubious BSD thing... Probably nobody even uses it, but
1739 	 * the UNIX standard wants it for whatever reason... -DaveM
1740 	 */
1741 	case SO_ACCEPTCONN:
1742 		v.val = sk->sk_state == TCP_LISTEN;
1743 		break;
1744 
1745 	case SO_PASSSEC:
1746 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1747 		break;
1748 
1749 	case SO_PEERSEC:
1750 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1751 
1752 	case SO_MARK:
1753 		v.val = sk->sk_mark;
1754 		break;
1755 
1756 	case SO_RCVMARK:
1757 		v.val = sock_flag(sk, SOCK_RCVMARK);
1758 		break;
1759 
1760 	case SO_RXQ_OVFL:
1761 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1762 		break;
1763 
1764 	case SO_WIFI_STATUS:
1765 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1766 		break;
1767 
1768 	case SO_PEEK_OFF:
1769 		if (!sock->ops->set_peek_off)
1770 			return -EOPNOTSUPP;
1771 
1772 		v.val = sk->sk_peek_off;
1773 		break;
1774 	case SO_NOFCS:
1775 		v.val = sock_flag(sk, SOCK_NOFCS);
1776 		break;
1777 
1778 	case SO_BINDTODEVICE:
1779 		return sock_getbindtodevice(sk, optval, optlen, len);
1780 
1781 	case SO_GET_FILTER:
1782 		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1783 		if (len < 0)
1784 			return len;
1785 
1786 		goto lenout;
1787 
1788 	case SO_LOCK_FILTER:
1789 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1790 		break;
1791 
1792 	case SO_BPF_EXTENSIONS:
1793 		v.val = bpf_tell_extensions();
1794 		break;
1795 
1796 	case SO_SELECT_ERR_QUEUE:
1797 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1798 		break;
1799 
1800 #ifdef CONFIG_NET_RX_BUSY_POLL
1801 	case SO_BUSY_POLL:
1802 		v.val = sk->sk_ll_usec;
1803 		break;
1804 	case SO_PREFER_BUSY_POLL:
1805 		v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1806 		break;
1807 #endif
1808 
1809 	case SO_MAX_PACING_RATE:
1810 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1811 			lv = sizeof(v.ulval);
1812 			v.ulval = sk->sk_max_pacing_rate;
1813 		} else {
1814 			/* 32bit version */
1815 			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1816 		}
1817 		break;
1818 
1819 	case SO_INCOMING_CPU:
1820 		v.val = READ_ONCE(sk->sk_incoming_cpu);
1821 		break;
1822 
1823 	case SO_MEMINFO:
1824 	{
1825 		u32 meminfo[SK_MEMINFO_VARS];
1826 
1827 		sk_get_meminfo(sk, meminfo);
1828 
1829 		len = min_t(unsigned int, len, sizeof(meminfo));
1830 		if (copy_to_user(optval, &meminfo, len))
1831 			return -EFAULT;
1832 
1833 		goto lenout;
1834 	}
1835 
1836 #ifdef CONFIG_NET_RX_BUSY_POLL
1837 	case SO_INCOMING_NAPI_ID:
1838 		v.val = READ_ONCE(sk->sk_napi_id);
1839 
1840 		/* aggregate non-NAPI IDs down to 0 */
1841 		if (v.val < MIN_NAPI_ID)
1842 			v.val = 0;
1843 
1844 		break;
1845 #endif
1846 
1847 	case SO_COOKIE:
1848 		lv = sizeof(u64);
1849 		if (len < lv)
1850 			return -EINVAL;
1851 		v.val64 = sock_gen_cookie(sk);
1852 		break;
1853 
1854 	case SO_ZEROCOPY:
1855 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1856 		break;
1857 
1858 	case SO_TXTIME:
1859 		lv = sizeof(v.txtime);
1860 		v.txtime.clockid = sk->sk_clockid;
1861 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1862 				  SOF_TXTIME_DEADLINE_MODE : 0;
1863 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1864 				  SOF_TXTIME_REPORT_ERRORS : 0;
1865 		break;
1866 
1867 	case SO_BINDTOIFINDEX:
1868 		v.val = READ_ONCE(sk->sk_bound_dev_if);
1869 		break;
1870 
1871 	case SO_NETNS_COOKIE:
1872 		lv = sizeof(u64);
1873 		if (len != lv)
1874 			return -EINVAL;
1875 		v.val64 = sock_net(sk)->net_cookie;
1876 		break;
1877 
1878 	case SO_BUF_LOCK:
1879 		v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1880 		break;
1881 
1882 	case SO_RESERVE_MEM:
1883 		v.val = sk->sk_reserved_mem;
1884 		break;
1885 
1886 	case SO_TXREHASH:
1887 		v.val = sk->sk_txrehash;
1888 		break;
1889 
1890 	default:
1891 		/* We implement the SO_SNDLOWAT etc to not be settable
1892 		 * (1003.1g 7).
1893 		 */
1894 		return -ENOPROTOOPT;
1895 	}
1896 
1897 	if (len > lv)
1898 		len = lv;
1899 	if (copy_to_user(optval, &v, len))
1900 		return -EFAULT;
1901 lenout:
1902 	if (put_user(len, optlen))
1903 		return -EFAULT;
1904 	return 0;
1905 }
1906 
1907 /*
1908  * Initialize an sk_lock.
1909  *
1910  * (We also register the sk_lock with the lock validator.)
1911  */
1912 static inline void sock_lock_init(struct sock *sk)
1913 {
1914 	if (sk->sk_kern_sock)
1915 		sock_lock_init_class_and_name(
1916 			sk,
1917 			af_family_kern_slock_key_strings[sk->sk_family],
1918 			af_family_kern_slock_keys + sk->sk_family,
1919 			af_family_kern_key_strings[sk->sk_family],
1920 			af_family_kern_keys + sk->sk_family);
1921 	else
1922 		sock_lock_init_class_and_name(
1923 			sk,
1924 			af_family_slock_key_strings[sk->sk_family],
1925 			af_family_slock_keys + sk->sk_family,
1926 			af_family_key_strings[sk->sk_family],
1927 			af_family_keys + sk->sk_family);
1928 }
1929 
1930 /*
1931  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1932  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1933  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1934  */
1935 static void sock_copy(struct sock *nsk, const struct sock *osk)
1936 {
1937 	const struct proto *prot = READ_ONCE(osk->sk_prot);
1938 #ifdef CONFIG_SECURITY_NETWORK
1939 	void *sptr = nsk->sk_security;
1940 #endif
1941 
1942 	/* If we move sk_tx_queue_mapping out of the private section,
1943 	 * we must check if sk_tx_queue_clear() is called after
1944 	 * sock_copy() in sk_clone_lock().
1945 	 */
1946 	BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
1947 		     offsetof(struct sock, sk_dontcopy_begin) ||
1948 		     offsetof(struct sock, sk_tx_queue_mapping) >=
1949 		     offsetof(struct sock, sk_dontcopy_end));
1950 
1951 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1952 
1953 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1954 	       prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1955 
1956 #ifdef CONFIG_SECURITY_NETWORK
1957 	nsk->sk_security = sptr;
1958 	security_sk_clone(osk, nsk);
1959 #endif
1960 }
1961 
1962 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1963 		int family)
1964 {
1965 	struct sock *sk;
1966 	struct kmem_cache *slab;
1967 
1968 	slab = prot->slab;
1969 	if (slab != NULL) {
1970 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1971 		if (!sk)
1972 			return sk;
1973 		if (want_init_on_alloc(priority))
1974 			sk_prot_clear_nulls(sk, prot->obj_size);
1975 	} else
1976 		sk = kmalloc(prot->obj_size, priority);
1977 
1978 	if (sk != NULL) {
1979 		if (security_sk_alloc(sk, family, priority))
1980 			goto out_free;
1981 
1982 		if (!try_module_get(prot->owner))
1983 			goto out_free_sec;
1984 	}
1985 
1986 	return sk;
1987 
1988 out_free_sec:
1989 	security_sk_free(sk);
1990 out_free:
1991 	if (slab != NULL)
1992 		kmem_cache_free(slab, sk);
1993 	else
1994 		kfree(sk);
1995 	return NULL;
1996 }
1997 
1998 static void sk_prot_free(struct proto *prot, struct sock *sk)
1999 {
2000 	struct kmem_cache *slab;
2001 	struct module *owner;
2002 
2003 	owner = prot->owner;
2004 	slab = prot->slab;
2005 
2006 	cgroup_sk_free(&sk->sk_cgrp_data);
2007 	mem_cgroup_sk_free(sk);
2008 	security_sk_free(sk);
2009 	if (slab != NULL)
2010 		kmem_cache_free(slab, sk);
2011 	else
2012 		kfree(sk);
2013 	module_put(owner);
2014 }
2015 
2016 /**
2017  *	sk_alloc - All socket objects are allocated here
2018  *	@net: the applicable net namespace
2019  *	@family: protocol family
2020  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2021  *	@prot: struct proto associated with this new sock instance
2022  *	@kern: is this to be a kernel socket?
2023  */
2024 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2025 		      struct proto *prot, int kern)
2026 {
2027 	struct sock *sk;
2028 
2029 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2030 	if (sk) {
2031 		sk->sk_family = family;
2032 		/*
2033 		 * See comment in struct sock definition to understand
2034 		 * why we need sk_prot_creator -acme
2035 		 */
2036 		sk->sk_prot = sk->sk_prot_creator = prot;
2037 		sk->sk_kern_sock = kern;
2038 		sock_lock_init(sk);
2039 		sk->sk_net_refcnt = kern ? 0 : 1;
2040 		if (likely(sk->sk_net_refcnt)) {
2041 			get_net_track(net, &sk->ns_tracker, priority);
2042 			sock_inuse_add(net, 1);
2043 		}
2044 
2045 		sock_net_set(sk, net);
2046 		refcount_set(&sk->sk_wmem_alloc, 1);
2047 
2048 		mem_cgroup_sk_alloc(sk);
2049 		cgroup_sk_alloc(&sk->sk_cgrp_data);
2050 		sock_update_classid(&sk->sk_cgrp_data);
2051 		sock_update_netprioidx(&sk->sk_cgrp_data);
2052 		sk_tx_queue_clear(sk);
2053 	}
2054 
2055 	return sk;
2056 }
2057 EXPORT_SYMBOL(sk_alloc);
2058 
2059 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2060  * grace period. This is the case for UDP sockets and TCP listeners.
2061  */
2062 static void __sk_destruct(struct rcu_head *head)
2063 {
2064 	struct sock *sk = container_of(head, struct sock, sk_rcu);
2065 	struct sk_filter *filter;
2066 
2067 	if (sk->sk_destruct)
2068 		sk->sk_destruct(sk);
2069 
2070 	filter = rcu_dereference_check(sk->sk_filter,
2071 				       refcount_read(&sk->sk_wmem_alloc) == 0);
2072 	if (filter) {
2073 		sk_filter_uncharge(sk, filter);
2074 		RCU_INIT_POINTER(sk->sk_filter, NULL);
2075 	}
2076 
2077 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2078 
2079 #ifdef CONFIG_BPF_SYSCALL
2080 	bpf_sk_storage_free(sk);
2081 #endif
2082 
2083 	if (atomic_read(&sk->sk_omem_alloc))
2084 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
2085 			 __func__, atomic_read(&sk->sk_omem_alloc));
2086 
2087 	if (sk->sk_frag.page) {
2088 		put_page(sk->sk_frag.page);
2089 		sk->sk_frag.page = NULL;
2090 	}
2091 
2092 	/* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2093 	put_cred(sk->sk_peer_cred);
2094 	put_pid(sk->sk_peer_pid);
2095 
2096 	if (likely(sk->sk_net_refcnt))
2097 		put_net_track(sock_net(sk), &sk->ns_tracker);
2098 	sk_prot_free(sk->sk_prot_creator, sk);
2099 }
2100 
2101 void sk_destruct(struct sock *sk)
2102 {
2103 	bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2104 
2105 	if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2106 		reuseport_detach_sock(sk);
2107 		use_call_rcu = true;
2108 	}
2109 
2110 	if (use_call_rcu)
2111 		call_rcu(&sk->sk_rcu, __sk_destruct);
2112 	else
2113 		__sk_destruct(&sk->sk_rcu);
2114 }
2115 
2116 static void __sk_free(struct sock *sk)
2117 {
2118 	if (likely(sk->sk_net_refcnt))
2119 		sock_inuse_add(sock_net(sk), -1);
2120 
2121 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2122 		sock_diag_broadcast_destroy(sk);
2123 	else
2124 		sk_destruct(sk);
2125 }
2126 
2127 void sk_free(struct sock *sk)
2128 {
2129 	/*
2130 	 * We subtract one from sk_wmem_alloc and can know if
2131 	 * some packets are still in some tx queue.
2132 	 * If not null, sock_wfree() will call __sk_free(sk) later
2133 	 */
2134 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2135 		__sk_free(sk);
2136 }
2137 EXPORT_SYMBOL(sk_free);
2138 
2139 static void sk_init_common(struct sock *sk)
2140 {
2141 	skb_queue_head_init(&sk->sk_receive_queue);
2142 	skb_queue_head_init(&sk->sk_write_queue);
2143 	skb_queue_head_init(&sk->sk_error_queue);
2144 
2145 	rwlock_init(&sk->sk_callback_lock);
2146 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2147 			af_rlock_keys + sk->sk_family,
2148 			af_family_rlock_key_strings[sk->sk_family]);
2149 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2150 			af_wlock_keys + sk->sk_family,
2151 			af_family_wlock_key_strings[sk->sk_family]);
2152 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2153 			af_elock_keys + sk->sk_family,
2154 			af_family_elock_key_strings[sk->sk_family]);
2155 	lockdep_set_class_and_name(&sk->sk_callback_lock,
2156 			af_callback_keys + sk->sk_family,
2157 			af_family_clock_key_strings[sk->sk_family]);
2158 }
2159 
2160 /**
2161  *	sk_clone_lock - clone a socket, and lock its clone
2162  *	@sk: the socket to clone
2163  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2164  *
2165  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2166  */
2167 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2168 {
2169 	struct proto *prot = READ_ONCE(sk->sk_prot);
2170 	struct sk_filter *filter;
2171 	bool is_charged = true;
2172 	struct sock *newsk;
2173 
2174 	newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2175 	if (!newsk)
2176 		goto out;
2177 
2178 	sock_copy(newsk, sk);
2179 
2180 	newsk->sk_prot_creator = prot;
2181 
2182 	/* SANITY */
2183 	if (likely(newsk->sk_net_refcnt)) {
2184 		get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2185 		sock_inuse_add(sock_net(newsk), 1);
2186 	}
2187 	sk_node_init(&newsk->sk_node);
2188 	sock_lock_init(newsk);
2189 	bh_lock_sock(newsk);
2190 	newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
2191 	newsk->sk_backlog.len = 0;
2192 
2193 	atomic_set(&newsk->sk_rmem_alloc, 0);
2194 
2195 	/* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2196 	refcount_set(&newsk->sk_wmem_alloc, 1);
2197 
2198 	atomic_set(&newsk->sk_omem_alloc, 0);
2199 	sk_init_common(newsk);
2200 
2201 	newsk->sk_dst_cache	= NULL;
2202 	newsk->sk_dst_pending_confirm = 0;
2203 	newsk->sk_wmem_queued	= 0;
2204 	newsk->sk_forward_alloc = 0;
2205 	newsk->sk_reserved_mem  = 0;
2206 	atomic_set(&newsk->sk_drops, 0);
2207 	newsk->sk_send_head	= NULL;
2208 	newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2209 	atomic_set(&newsk->sk_zckey, 0);
2210 
2211 	sock_reset_flag(newsk, SOCK_DONE);
2212 
2213 	/* sk->sk_memcg will be populated at accept() time */
2214 	newsk->sk_memcg = NULL;
2215 
2216 	cgroup_sk_clone(&newsk->sk_cgrp_data);
2217 
2218 	rcu_read_lock();
2219 	filter = rcu_dereference(sk->sk_filter);
2220 	if (filter != NULL)
2221 		/* though it's an empty new sock, the charging may fail
2222 		 * if sysctl_optmem_max was changed between creation of
2223 		 * original socket and cloning
2224 		 */
2225 		is_charged = sk_filter_charge(newsk, filter);
2226 	RCU_INIT_POINTER(newsk->sk_filter, filter);
2227 	rcu_read_unlock();
2228 
2229 	if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2230 		/* We need to make sure that we don't uncharge the new
2231 		 * socket if we couldn't charge it in the first place
2232 		 * as otherwise we uncharge the parent's filter.
2233 		 */
2234 		if (!is_charged)
2235 			RCU_INIT_POINTER(newsk->sk_filter, NULL);
2236 		sk_free_unlock_clone(newsk);
2237 		newsk = NULL;
2238 		goto out;
2239 	}
2240 	RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2241 
2242 	if (bpf_sk_storage_clone(sk, newsk)) {
2243 		sk_free_unlock_clone(newsk);
2244 		newsk = NULL;
2245 		goto out;
2246 	}
2247 
2248 	/* Clear sk_user_data if parent had the pointer tagged
2249 	 * as not suitable for copying when cloning.
2250 	 */
2251 	if (sk_user_data_is_nocopy(newsk))
2252 		newsk->sk_user_data = NULL;
2253 
2254 	newsk->sk_err	   = 0;
2255 	newsk->sk_err_soft = 0;
2256 	newsk->sk_priority = 0;
2257 	newsk->sk_incoming_cpu = raw_smp_processor_id();
2258 
2259 	/* Before updating sk_refcnt, we must commit prior changes to memory
2260 	 * (Documentation/RCU/rculist_nulls.rst for details)
2261 	 */
2262 	smp_wmb();
2263 	refcount_set(&newsk->sk_refcnt, 2);
2264 
2265 	/* Increment the counter in the same struct proto as the master
2266 	 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
2267 	 * is the same as sk->sk_prot->socks, as this field was copied
2268 	 * with memcpy).
2269 	 *
2270 	 * This _changes_ the previous behaviour, where
2271 	 * tcp_create_openreq_child always was incrementing the
2272 	 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
2273 	 * to be taken into account in all callers. -acme
2274 	 */
2275 	sk_refcnt_debug_inc(newsk);
2276 	sk_set_socket(newsk, NULL);
2277 	sk_tx_queue_clear(newsk);
2278 	RCU_INIT_POINTER(newsk->sk_wq, NULL);
2279 
2280 	if (newsk->sk_prot->sockets_allocated)
2281 		sk_sockets_allocated_inc(newsk);
2282 
2283 	if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2284 		net_enable_timestamp();
2285 out:
2286 	return newsk;
2287 }
2288 EXPORT_SYMBOL_GPL(sk_clone_lock);
2289 
2290 void sk_free_unlock_clone(struct sock *sk)
2291 {
2292 	/* It is still raw copy of parent, so invalidate
2293 	 * destructor and make plain sk_free() */
2294 	sk->sk_destruct = NULL;
2295 	bh_unlock_sock(sk);
2296 	sk_free(sk);
2297 }
2298 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2299 
2300 static void sk_trim_gso_size(struct sock *sk)
2301 {
2302 	if (sk->sk_gso_max_size <= GSO_LEGACY_MAX_SIZE)
2303 		return;
2304 #if IS_ENABLED(CONFIG_IPV6)
2305 	if (sk->sk_family == AF_INET6 &&
2306 	    sk_is_tcp(sk) &&
2307 	    !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
2308 		return;
2309 #endif
2310 	sk->sk_gso_max_size = GSO_LEGACY_MAX_SIZE;
2311 }
2312 
2313 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2314 {
2315 	u32 max_segs = 1;
2316 
2317 	sk_dst_set(sk, dst);
2318 	sk->sk_route_caps = dst->dev->features;
2319 	if (sk_is_tcp(sk))
2320 		sk->sk_route_caps |= NETIF_F_GSO;
2321 	if (sk->sk_route_caps & NETIF_F_GSO)
2322 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2323 	if (unlikely(sk->sk_gso_disabled))
2324 		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2325 	if (sk_can_gso(sk)) {
2326 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2327 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2328 		} else {
2329 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2330 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_size() */
2331 			sk->sk_gso_max_size = READ_ONCE(dst->dev->gso_max_size);
2332 			sk_trim_gso_size(sk);
2333 			sk->sk_gso_max_size -= (MAX_TCP_HEADER + 1);
2334 			/* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2335 			max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2336 		}
2337 	}
2338 	sk->sk_gso_max_segs = max_segs;
2339 }
2340 EXPORT_SYMBOL_GPL(sk_setup_caps);
2341 
2342 /*
2343  *	Simple resource managers for sockets.
2344  */
2345 
2346 
2347 /*
2348  * Write buffer destructor automatically called from kfree_skb.
2349  */
2350 void sock_wfree(struct sk_buff *skb)
2351 {
2352 	struct sock *sk = skb->sk;
2353 	unsigned int len = skb->truesize;
2354 	bool free;
2355 
2356 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2357 		if (sock_flag(sk, SOCK_RCU_FREE) &&
2358 		    sk->sk_write_space == sock_def_write_space) {
2359 			rcu_read_lock();
2360 			free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2361 			sock_def_write_space_wfree(sk);
2362 			rcu_read_unlock();
2363 			if (unlikely(free))
2364 				__sk_free(sk);
2365 			return;
2366 		}
2367 
2368 		/*
2369 		 * Keep a reference on sk_wmem_alloc, this will be released
2370 		 * after sk_write_space() call
2371 		 */
2372 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2373 		sk->sk_write_space(sk);
2374 		len = 1;
2375 	}
2376 	/*
2377 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2378 	 * could not do because of in-flight packets
2379 	 */
2380 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2381 		__sk_free(sk);
2382 }
2383 EXPORT_SYMBOL(sock_wfree);
2384 
2385 /* This variant of sock_wfree() is used by TCP,
2386  * since it sets SOCK_USE_WRITE_QUEUE.
2387  */
2388 void __sock_wfree(struct sk_buff *skb)
2389 {
2390 	struct sock *sk = skb->sk;
2391 
2392 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2393 		__sk_free(sk);
2394 }
2395 
2396 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2397 {
2398 	skb_orphan(skb);
2399 	skb->sk = sk;
2400 #ifdef CONFIG_INET
2401 	if (unlikely(!sk_fullsock(sk))) {
2402 		skb->destructor = sock_edemux;
2403 		sock_hold(sk);
2404 		return;
2405 	}
2406 #endif
2407 	skb->destructor = sock_wfree;
2408 	skb_set_hash_from_sk(skb, sk);
2409 	/*
2410 	 * We used to take a refcount on sk, but following operation
2411 	 * is enough to guarantee sk_free() wont free this sock until
2412 	 * all in-flight packets are completed
2413 	 */
2414 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2415 }
2416 EXPORT_SYMBOL(skb_set_owner_w);
2417 
2418 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2419 {
2420 #ifdef CONFIG_TLS_DEVICE
2421 	/* Drivers depend on in-order delivery for crypto offload,
2422 	 * partial orphan breaks out-of-order-OK logic.
2423 	 */
2424 	if (skb->decrypted)
2425 		return false;
2426 #endif
2427 	return (skb->destructor == sock_wfree ||
2428 		(IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2429 }
2430 
2431 /* This helper is used by netem, as it can hold packets in its
2432  * delay queue. We want to allow the owner socket to send more
2433  * packets, as if they were already TX completed by a typical driver.
2434  * But we also want to keep skb->sk set because some packet schedulers
2435  * rely on it (sch_fq for example).
2436  */
2437 void skb_orphan_partial(struct sk_buff *skb)
2438 {
2439 	if (skb_is_tcp_pure_ack(skb))
2440 		return;
2441 
2442 	if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2443 		return;
2444 
2445 	skb_orphan(skb);
2446 }
2447 EXPORT_SYMBOL(skb_orphan_partial);
2448 
2449 /*
2450  * Read buffer destructor automatically called from kfree_skb.
2451  */
2452 void sock_rfree(struct sk_buff *skb)
2453 {
2454 	struct sock *sk = skb->sk;
2455 	unsigned int len = skb->truesize;
2456 
2457 	atomic_sub(len, &sk->sk_rmem_alloc);
2458 	sk_mem_uncharge(sk, len);
2459 }
2460 EXPORT_SYMBOL(sock_rfree);
2461 
2462 /*
2463  * Buffer destructor for skbs that are not used directly in read or write
2464  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2465  */
2466 void sock_efree(struct sk_buff *skb)
2467 {
2468 	sock_put(skb->sk);
2469 }
2470 EXPORT_SYMBOL(sock_efree);
2471 
2472 /* Buffer destructor for prefetch/receive path where reference count may
2473  * not be held, e.g. for listen sockets.
2474  */
2475 #ifdef CONFIG_INET
2476 void sock_pfree(struct sk_buff *skb)
2477 {
2478 	if (sk_is_refcounted(skb->sk))
2479 		sock_gen_put(skb->sk);
2480 }
2481 EXPORT_SYMBOL(sock_pfree);
2482 #endif /* CONFIG_INET */
2483 
2484 kuid_t sock_i_uid(struct sock *sk)
2485 {
2486 	kuid_t uid;
2487 
2488 	read_lock_bh(&sk->sk_callback_lock);
2489 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2490 	read_unlock_bh(&sk->sk_callback_lock);
2491 	return uid;
2492 }
2493 EXPORT_SYMBOL(sock_i_uid);
2494 
2495 unsigned long sock_i_ino(struct sock *sk)
2496 {
2497 	unsigned long ino;
2498 
2499 	read_lock_bh(&sk->sk_callback_lock);
2500 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2501 	read_unlock_bh(&sk->sk_callback_lock);
2502 	return ino;
2503 }
2504 EXPORT_SYMBOL(sock_i_ino);
2505 
2506 /*
2507  * Allocate a skb from the socket's send buffer.
2508  */
2509 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2510 			     gfp_t priority)
2511 {
2512 	if (force ||
2513 	    refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2514 		struct sk_buff *skb = alloc_skb(size, priority);
2515 
2516 		if (skb) {
2517 			skb_set_owner_w(skb, sk);
2518 			return skb;
2519 		}
2520 	}
2521 	return NULL;
2522 }
2523 EXPORT_SYMBOL(sock_wmalloc);
2524 
2525 static void sock_ofree(struct sk_buff *skb)
2526 {
2527 	struct sock *sk = skb->sk;
2528 
2529 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2530 }
2531 
2532 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2533 			     gfp_t priority)
2534 {
2535 	struct sk_buff *skb;
2536 
2537 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2538 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2539 	    READ_ONCE(sysctl_optmem_max))
2540 		return NULL;
2541 
2542 	skb = alloc_skb(size, priority);
2543 	if (!skb)
2544 		return NULL;
2545 
2546 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2547 	skb->sk = sk;
2548 	skb->destructor = sock_ofree;
2549 	return skb;
2550 }
2551 
2552 /*
2553  * Allocate a memory block from the socket's option memory buffer.
2554  */
2555 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2556 {
2557 	int optmem_max = READ_ONCE(sysctl_optmem_max);
2558 
2559 	if ((unsigned int)size <= optmem_max &&
2560 	    atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2561 		void *mem;
2562 		/* First do the add, to avoid the race if kmalloc
2563 		 * might sleep.
2564 		 */
2565 		atomic_add(size, &sk->sk_omem_alloc);
2566 		mem = kmalloc(size, priority);
2567 		if (mem)
2568 			return mem;
2569 		atomic_sub(size, &sk->sk_omem_alloc);
2570 	}
2571 	return NULL;
2572 }
2573 EXPORT_SYMBOL(sock_kmalloc);
2574 
2575 /* Free an option memory block. Note, we actually want the inline
2576  * here as this allows gcc to detect the nullify and fold away the
2577  * condition entirely.
2578  */
2579 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2580 				  const bool nullify)
2581 {
2582 	if (WARN_ON_ONCE(!mem))
2583 		return;
2584 	if (nullify)
2585 		kfree_sensitive(mem);
2586 	else
2587 		kfree(mem);
2588 	atomic_sub(size, &sk->sk_omem_alloc);
2589 }
2590 
2591 void sock_kfree_s(struct sock *sk, void *mem, int size)
2592 {
2593 	__sock_kfree_s(sk, mem, size, false);
2594 }
2595 EXPORT_SYMBOL(sock_kfree_s);
2596 
2597 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2598 {
2599 	__sock_kfree_s(sk, mem, size, true);
2600 }
2601 EXPORT_SYMBOL(sock_kzfree_s);
2602 
2603 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2604    I think, these locks should be removed for datagram sockets.
2605  */
2606 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2607 {
2608 	DEFINE_WAIT(wait);
2609 
2610 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2611 	for (;;) {
2612 		if (!timeo)
2613 			break;
2614 		if (signal_pending(current))
2615 			break;
2616 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2617 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2618 		if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2619 			break;
2620 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2621 			break;
2622 		if (sk->sk_err)
2623 			break;
2624 		timeo = schedule_timeout(timeo);
2625 	}
2626 	finish_wait(sk_sleep(sk), &wait);
2627 	return timeo;
2628 }
2629 
2630 
2631 /*
2632  *	Generic send/receive buffer handlers
2633  */
2634 
2635 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2636 				     unsigned long data_len, int noblock,
2637 				     int *errcode, int max_page_order)
2638 {
2639 	struct sk_buff *skb;
2640 	long timeo;
2641 	int err;
2642 
2643 	timeo = sock_sndtimeo(sk, noblock);
2644 	for (;;) {
2645 		err = sock_error(sk);
2646 		if (err != 0)
2647 			goto failure;
2648 
2649 		err = -EPIPE;
2650 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2651 			goto failure;
2652 
2653 		if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2654 			break;
2655 
2656 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2657 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2658 		err = -EAGAIN;
2659 		if (!timeo)
2660 			goto failure;
2661 		if (signal_pending(current))
2662 			goto interrupted;
2663 		timeo = sock_wait_for_wmem(sk, timeo);
2664 	}
2665 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2666 				   errcode, sk->sk_allocation);
2667 	if (skb)
2668 		skb_set_owner_w(skb, sk);
2669 	return skb;
2670 
2671 interrupted:
2672 	err = sock_intr_errno(timeo);
2673 failure:
2674 	*errcode = err;
2675 	return NULL;
2676 }
2677 EXPORT_SYMBOL(sock_alloc_send_pskb);
2678 
2679 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2680 		     struct sockcm_cookie *sockc)
2681 {
2682 	u32 tsflags;
2683 
2684 	switch (cmsg->cmsg_type) {
2685 	case SO_MARK:
2686 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2687 		    !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2688 			return -EPERM;
2689 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2690 			return -EINVAL;
2691 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2692 		break;
2693 	case SO_TIMESTAMPING_OLD:
2694 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2695 			return -EINVAL;
2696 
2697 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2698 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2699 			return -EINVAL;
2700 
2701 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2702 		sockc->tsflags |= tsflags;
2703 		break;
2704 	case SCM_TXTIME:
2705 		if (!sock_flag(sk, SOCK_TXTIME))
2706 			return -EINVAL;
2707 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2708 			return -EINVAL;
2709 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2710 		break;
2711 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2712 	case SCM_RIGHTS:
2713 	case SCM_CREDENTIALS:
2714 		break;
2715 	default:
2716 		return -EINVAL;
2717 	}
2718 	return 0;
2719 }
2720 EXPORT_SYMBOL(__sock_cmsg_send);
2721 
2722 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2723 		   struct sockcm_cookie *sockc)
2724 {
2725 	struct cmsghdr *cmsg;
2726 	int ret;
2727 
2728 	for_each_cmsghdr(cmsg, msg) {
2729 		if (!CMSG_OK(msg, cmsg))
2730 			return -EINVAL;
2731 		if (cmsg->cmsg_level != SOL_SOCKET)
2732 			continue;
2733 		ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2734 		if (ret)
2735 			return ret;
2736 	}
2737 	return 0;
2738 }
2739 EXPORT_SYMBOL(sock_cmsg_send);
2740 
2741 static void sk_enter_memory_pressure(struct sock *sk)
2742 {
2743 	if (!sk->sk_prot->enter_memory_pressure)
2744 		return;
2745 
2746 	sk->sk_prot->enter_memory_pressure(sk);
2747 }
2748 
2749 static void sk_leave_memory_pressure(struct sock *sk)
2750 {
2751 	if (sk->sk_prot->leave_memory_pressure) {
2752 		sk->sk_prot->leave_memory_pressure(sk);
2753 	} else {
2754 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2755 
2756 		if (memory_pressure && READ_ONCE(*memory_pressure))
2757 			WRITE_ONCE(*memory_pressure, 0);
2758 	}
2759 }
2760 
2761 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2762 
2763 /**
2764  * skb_page_frag_refill - check that a page_frag contains enough room
2765  * @sz: minimum size of the fragment we want to get
2766  * @pfrag: pointer to page_frag
2767  * @gfp: priority for memory allocation
2768  *
2769  * Note: While this allocator tries to use high order pages, there is
2770  * no guarantee that allocations succeed. Therefore, @sz MUST be
2771  * less or equal than PAGE_SIZE.
2772  */
2773 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2774 {
2775 	if (pfrag->page) {
2776 		if (page_ref_count(pfrag->page) == 1) {
2777 			pfrag->offset = 0;
2778 			return true;
2779 		}
2780 		if (pfrag->offset + sz <= pfrag->size)
2781 			return true;
2782 		put_page(pfrag->page);
2783 	}
2784 
2785 	pfrag->offset = 0;
2786 	if (SKB_FRAG_PAGE_ORDER &&
2787 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2788 		/* Avoid direct reclaim but allow kswapd to wake */
2789 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2790 					  __GFP_COMP | __GFP_NOWARN |
2791 					  __GFP_NORETRY,
2792 					  SKB_FRAG_PAGE_ORDER);
2793 		if (likely(pfrag->page)) {
2794 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2795 			return true;
2796 		}
2797 	}
2798 	pfrag->page = alloc_page(gfp);
2799 	if (likely(pfrag->page)) {
2800 		pfrag->size = PAGE_SIZE;
2801 		return true;
2802 	}
2803 	return false;
2804 }
2805 EXPORT_SYMBOL(skb_page_frag_refill);
2806 
2807 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2808 {
2809 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2810 		return true;
2811 
2812 	sk_enter_memory_pressure(sk);
2813 	sk_stream_moderate_sndbuf(sk);
2814 	return false;
2815 }
2816 EXPORT_SYMBOL(sk_page_frag_refill);
2817 
2818 void __lock_sock(struct sock *sk)
2819 	__releases(&sk->sk_lock.slock)
2820 	__acquires(&sk->sk_lock.slock)
2821 {
2822 	DEFINE_WAIT(wait);
2823 
2824 	for (;;) {
2825 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2826 					TASK_UNINTERRUPTIBLE);
2827 		spin_unlock_bh(&sk->sk_lock.slock);
2828 		schedule();
2829 		spin_lock_bh(&sk->sk_lock.slock);
2830 		if (!sock_owned_by_user(sk))
2831 			break;
2832 	}
2833 	finish_wait(&sk->sk_lock.wq, &wait);
2834 }
2835 
2836 void __release_sock(struct sock *sk)
2837 	__releases(&sk->sk_lock.slock)
2838 	__acquires(&sk->sk_lock.slock)
2839 {
2840 	struct sk_buff *skb, *next;
2841 
2842 	while ((skb = sk->sk_backlog.head) != NULL) {
2843 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2844 
2845 		spin_unlock_bh(&sk->sk_lock.slock);
2846 
2847 		do {
2848 			next = skb->next;
2849 			prefetch(next);
2850 			DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2851 			skb_mark_not_on_list(skb);
2852 			sk_backlog_rcv(sk, skb);
2853 
2854 			cond_resched();
2855 
2856 			skb = next;
2857 		} while (skb != NULL);
2858 
2859 		spin_lock_bh(&sk->sk_lock.slock);
2860 	}
2861 
2862 	/*
2863 	 * Doing the zeroing here guarantee we can not loop forever
2864 	 * while a wild producer attempts to flood us.
2865 	 */
2866 	sk->sk_backlog.len = 0;
2867 }
2868 
2869 void __sk_flush_backlog(struct sock *sk)
2870 {
2871 	spin_lock_bh(&sk->sk_lock.slock);
2872 	__release_sock(sk);
2873 	spin_unlock_bh(&sk->sk_lock.slock);
2874 }
2875 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
2876 
2877 /**
2878  * sk_wait_data - wait for data to arrive at sk_receive_queue
2879  * @sk:    sock to wait on
2880  * @timeo: for how long
2881  * @skb:   last skb seen on sk_receive_queue
2882  *
2883  * Now socket state including sk->sk_err is changed only under lock,
2884  * hence we may omit checks after joining wait queue.
2885  * We check receive queue before schedule() only as optimization;
2886  * it is very likely that release_sock() added new data.
2887  */
2888 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2889 {
2890 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2891 	int rc;
2892 
2893 	add_wait_queue(sk_sleep(sk), &wait);
2894 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2895 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2896 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2897 	remove_wait_queue(sk_sleep(sk), &wait);
2898 	return rc;
2899 }
2900 EXPORT_SYMBOL(sk_wait_data);
2901 
2902 /**
2903  *	__sk_mem_raise_allocated - increase memory_allocated
2904  *	@sk: socket
2905  *	@size: memory size to allocate
2906  *	@amt: pages to allocate
2907  *	@kind: allocation type
2908  *
2909  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2910  */
2911 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2912 {
2913 	bool memcg_charge = mem_cgroup_sockets_enabled && sk->sk_memcg;
2914 	struct proto *prot = sk->sk_prot;
2915 	bool charged = true;
2916 	long allocated;
2917 
2918 	sk_memory_allocated_add(sk, amt);
2919 	allocated = sk_memory_allocated(sk);
2920 	if (memcg_charge &&
2921 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt,
2922 						gfp_memcg_charge())))
2923 		goto suppress_allocation;
2924 
2925 	/* Under limit. */
2926 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2927 		sk_leave_memory_pressure(sk);
2928 		return 1;
2929 	}
2930 
2931 	/* Under pressure. */
2932 	if (allocated > sk_prot_mem_limits(sk, 1))
2933 		sk_enter_memory_pressure(sk);
2934 
2935 	/* Over hard limit. */
2936 	if (allocated > sk_prot_mem_limits(sk, 2))
2937 		goto suppress_allocation;
2938 
2939 	/* guarantee minimum buffer size under pressure */
2940 	if (kind == SK_MEM_RECV) {
2941 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2942 			return 1;
2943 
2944 	} else { /* SK_MEM_SEND */
2945 		int wmem0 = sk_get_wmem0(sk, prot);
2946 
2947 		if (sk->sk_type == SOCK_STREAM) {
2948 			if (sk->sk_wmem_queued < wmem0)
2949 				return 1;
2950 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
2951 				return 1;
2952 		}
2953 	}
2954 
2955 	if (sk_has_memory_pressure(sk)) {
2956 		u64 alloc;
2957 
2958 		if (!sk_under_memory_pressure(sk))
2959 			return 1;
2960 		alloc = sk_sockets_allocated_read_positive(sk);
2961 		if (sk_prot_mem_limits(sk, 2) > alloc *
2962 		    sk_mem_pages(sk->sk_wmem_queued +
2963 				 atomic_read(&sk->sk_rmem_alloc) +
2964 				 sk->sk_forward_alloc))
2965 			return 1;
2966 	}
2967 
2968 suppress_allocation:
2969 
2970 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2971 		sk_stream_moderate_sndbuf(sk);
2972 
2973 		/* Fail only if socket is _under_ its sndbuf.
2974 		 * In this case we cannot block, so that we have to fail.
2975 		 */
2976 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
2977 			/* Force charge with __GFP_NOFAIL */
2978 			if (memcg_charge && !charged) {
2979 				mem_cgroup_charge_skmem(sk->sk_memcg, amt,
2980 					gfp_memcg_charge() | __GFP_NOFAIL);
2981 			}
2982 			return 1;
2983 		}
2984 	}
2985 
2986 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
2987 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
2988 
2989 	sk_memory_allocated_sub(sk, amt);
2990 
2991 	if (memcg_charge && charged)
2992 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2993 
2994 	return 0;
2995 }
2996 
2997 /**
2998  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2999  *	@sk: socket
3000  *	@size: memory size to allocate
3001  *	@kind: allocation type
3002  *
3003  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3004  *	rmem allocation. This function assumes that protocols which have
3005  *	memory_pressure use sk_wmem_queued as write buffer accounting.
3006  */
3007 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3008 {
3009 	int ret, amt = sk_mem_pages(size);
3010 
3011 	sk->sk_forward_alloc += amt << PAGE_SHIFT;
3012 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3013 	if (!ret)
3014 		sk->sk_forward_alloc -= amt << PAGE_SHIFT;
3015 	return ret;
3016 }
3017 EXPORT_SYMBOL(__sk_mem_schedule);
3018 
3019 /**
3020  *	__sk_mem_reduce_allocated - reclaim memory_allocated
3021  *	@sk: socket
3022  *	@amount: number of quanta
3023  *
3024  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3025  */
3026 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3027 {
3028 	sk_memory_allocated_sub(sk, amount);
3029 
3030 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3031 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3032 
3033 	if (sk_under_memory_pressure(sk) &&
3034 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3035 		sk_leave_memory_pressure(sk);
3036 }
3037 
3038 /**
3039  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3040  *	@sk: socket
3041  *	@amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3042  */
3043 void __sk_mem_reclaim(struct sock *sk, int amount)
3044 {
3045 	amount >>= PAGE_SHIFT;
3046 	sk->sk_forward_alloc -= amount << PAGE_SHIFT;
3047 	__sk_mem_reduce_allocated(sk, amount);
3048 }
3049 EXPORT_SYMBOL(__sk_mem_reclaim);
3050 
3051 int sk_set_peek_off(struct sock *sk, int val)
3052 {
3053 	sk->sk_peek_off = val;
3054 	return 0;
3055 }
3056 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3057 
3058 /*
3059  * Set of default routines for initialising struct proto_ops when
3060  * the protocol does not support a particular function. In certain
3061  * cases where it makes no sense for a protocol to have a "do nothing"
3062  * function, some default processing is provided.
3063  */
3064 
3065 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3066 {
3067 	return -EOPNOTSUPP;
3068 }
3069 EXPORT_SYMBOL(sock_no_bind);
3070 
3071 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3072 		    int len, int flags)
3073 {
3074 	return -EOPNOTSUPP;
3075 }
3076 EXPORT_SYMBOL(sock_no_connect);
3077 
3078 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3079 {
3080 	return -EOPNOTSUPP;
3081 }
3082 EXPORT_SYMBOL(sock_no_socketpair);
3083 
3084 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3085 		   bool kern)
3086 {
3087 	return -EOPNOTSUPP;
3088 }
3089 EXPORT_SYMBOL(sock_no_accept);
3090 
3091 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3092 		    int peer)
3093 {
3094 	return -EOPNOTSUPP;
3095 }
3096 EXPORT_SYMBOL(sock_no_getname);
3097 
3098 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3099 {
3100 	return -EOPNOTSUPP;
3101 }
3102 EXPORT_SYMBOL(sock_no_ioctl);
3103 
3104 int sock_no_listen(struct socket *sock, int backlog)
3105 {
3106 	return -EOPNOTSUPP;
3107 }
3108 EXPORT_SYMBOL(sock_no_listen);
3109 
3110 int sock_no_shutdown(struct socket *sock, int how)
3111 {
3112 	return -EOPNOTSUPP;
3113 }
3114 EXPORT_SYMBOL(sock_no_shutdown);
3115 
3116 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3117 {
3118 	return -EOPNOTSUPP;
3119 }
3120 EXPORT_SYMBOL(sock_no_sendmsg);
3121 
3122 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3123 {
3124 	return -EOPNOTSUPP;
3125 }
3126 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3127 
3128 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3129 		    int flags)
3130 {
3131 	return -EOPNOTSUPP;
3132 }
3133 EXPORT_SYMBOL(sock_no_recvmsg);
3134 
3135 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3136 {
3137 	/* Mirror missing mmap method error code */
3138 	return -ENODEV;
3139 }
3140 EXPORT_SYMBOL(sock_no_mmap);
3141 
3142 /*
3143  * When a file is received (via SCM_RIGHTS, etc), we must bump the
3144  * various sock-based usage counts.
3145  */
3146 void __receive_sock(struct file *file)
3147 {
3148 	struct socket *sock;
3149 
3150 	sock = sock_from_file(file);
3151 	if (sock) {
3152 		sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3153 		sock_update_classid(&sock->sk->sk_cgrp_data);
3154 	}
3155 }
3156 
3157 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
3158 {
3159 	ssize_t res;
3160 	struct msghdr msg = {.msg_flags = flags};
3161 	struct kvec iov;
3162 	char *kaddr = kmap(page);
3163 	iov.iov_base = kaddr + offset;
3164 	iov.iov_len = size;
3165 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
3166 	kunmap(page);
3167 	return res;
3168 }
3169 EXPORT_SYMBOL(sock_no_sendpage);
3170 
3171 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
3172 				int offset, size_t size, int flags)
3173 {
3174 	ssize_t res;
3175 	struct msghdr msg = {.msg_flags = flags};
3176 	struct kvec iov;
3177 	char *kaddr = kmap(page);
3178 
3179 	iov.iov_base = kaddr + offset;
3180 	iov.iov_len = size;
3181 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
3182 	kunmap(page);
3183 	return res;
3184 }
3185 EXPORT_SYMBOL(sock_no_sendpage_locked);
3186 
3187 /*
3188  *	Default Socket Callbacks
3189  */
3190 
3191 static void sock_def_wakeup(struct sock *sk)
3192 {
3193 	struct socket_wq *wq;
3194 
3195 	rcu_read_lock();
3196 	wq = rcu_dereference(sk->sk_wq);
3197 	if (skwq_has_sleeper(wq))
3198 		wake_up_interruptible_all(&wq->wait);
3199 	rcu_read_unlock();
3200 }
3201 
3202 static void sock_def_error_report(struct sock *sk)
3203 {
3204 	struct socket_wq *wq;
3205 
3206 	rcu_read_lock();
3207 	wq = rcu_dereference(sk->sk_wq);
3208 	if (skwq_has_sleeper(wq))
3209 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3210 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3211 	rcu_read_unlock();
3212 }
3213 
3214 void sock_def_readable(struct sock *sk)
3215 {
3216 	struct socket_wq *wq;
3217 
3218 	rcu_read_lock();
3219 	wq = rcu_dereference(sk->sk_wq);
3220 	if (skwq_has_sleeper(wq))
3221 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3222 						EPOLLRDNORM | EPOLLRDBAND);
3223 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3224 	rcu_read_unlock();
3225 }
3226 
3227 static void sock_def_write_space(struct sock *sk)
3228 {
3229 	struct socket_wq *wq;
3230 
3231 	rcu_read_lock();
3232 
3233 	/* Do not wake up a writer until he can make "significant"
3234 	 * progress.  --DaveM
3235 	 */
3236 	if (sock_writeable(sk)) {
3237 		wq = rcu_dereference(sk->sk_wq);
3238 		if (skwq_has_sleeper(wq))
3239 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3240 						EPOLLWRNORM | EPOLLWRBAND);
3241 
3242 		/* Should agree with poll, otherwise some programs break */
3243 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3244 	}
3245 
3246 	rcu_read_unlock();
3247 }
3248 
3249 /* An optimised version of sock_def_write_space(), should only be called
3250  * for SOCK_RCU_FREE sockets under RCU read section and after putting
3251  * ->sk_wmem_alloc.
3252  */
3253 static void sock_def_write_space_wfree(struct sock *sk)
3254 {
3255 	/* Do not wake up a writer until he can make "significant"
3256 	 * progress.  --DaveM
3257 	 */
3258 	if (sock_writeable(sk)) {
3259 		struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3260 
3261 		/* rely on refcount_sub from sock_wfree() */
3262 		smp_mb__after_atomic();
3263 		if (wq && waitqueue_active(&wq->wait))
3264 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3265 						EPOLLWRNORM | EPOLLWRBAND);
3266 
3267 		/* Should agree with poll, otherwise some programs break */
3268 		sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3269 	}
3270 }
3271 
3272 static void sock_def_destruct(struct sock *sk)
3273 {
3274 }
3275 
3276 void sk_send_sigurg(struct sock *sk)
3277 {
3278 	if (sk->sk_socket && sk->sk_socket->file)
3279 		if (send_sigurg(&sk->sk_socket->file->f_owner))
3280 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3281 }
3282 EXPORT_SYMBOL(sk_send_sigurg);
3283 
3284 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3285 		    unsigned long expires)
3286 {
3287 	if (!mod_timer(timer, expires))
3288 		sock_hold(sk);
3289 }
3290 EXPORT_SYMBOL(sk_reset_timer);
3291 
3292 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3293 {
3294 	if (del_timer(timer))
3295 		__sock_put(sk);
3296 }
3297 EXPORT_SYMBOL(sk_stop_timer);
3298 
3299 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3300 {
3301 	if (del_timer_sync(timer))
3302 		__sock_put(sk);
3303 }
3304 EXPORT_SYMBOL(sk_stop_timer_sync);
3305 
3306 void sock_init_data(struct socket *sock, struct sock *sk)
3307 {
3308 	sk_init_common(sk);
3309 	sk->sk_send_head	=	NULL;
3310 
3311 	timer_setup(&sk->sk_timer, NULL, 0);
3312 
3313 	sk->sk_allocation	=	GFP_KERNEL;
3314 	sk->sk_rcvbuf		=	READ_ONCE(sysctl_rmem_default);
3315 	sk->sk_sndbuf		=	READ_ONCE(sysctl_wmem_default);
3316 	sk->sk_state		=	TCP_CLOSE;
3317 	sk_set_socket(sk, sock);
3318 
3319 	sock_set_flag(sk, SOCK_ZAPPED);
3320 
3321 	if (sock) {
3322 		sk->sk_type	=	sock->type;
3323 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3324 		sock->sk	=	sk;
3325 		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
3326 	} else {
3327 		RCU_INIT_POINTER(sk->sk_wq, NULL);
3328 		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
3329 	}
3330 
3331 	rwlock_init(&sk->sk_callback_lock);
3332 	if (sk->sk_kern_sock)
3333 		lockdep_set_class_and_name(
3334 			&sk->sk_callback_lock,
3335 			af_kern_callback_keys + sk->sk_family,
3336 			af_family_kern_clock_key_strings[sk->sk_family]);
3337 	else
3338 		lockdep_set_class_and_name(
3339 			&sk->sk_callback_lock,
3340 			af_callback_keys + sk->sk_family,
3341 			af_family_clock_key_strings[sk->sk_family]);
3342 
3343 	sk->sk_state_change	=	sock_def_wakeup;
3344 	sk->sk_data_ready	=	sock_def_readable;
3345 	sk->sk_write_space	=	sock_def_write_space;
3346 	sk->sk_error_report	=	sock_def_error_report;
3347 	sk->sk_destruct		=	sock_def_destruct;
3348 
3349 	sk->sk_frag.page	=	NULL;
3350 	sk->sk_frag.offset	=	0;
3351 	sk->sk_peek_off		=	-1;
3352 
3353 	sk->sk_peer_pid 	=	NULL;
3354 	sk->sk_peer_cred	=	NULL;
3355 	spin_lock_init(&sk->sk_peer_lock);
3356 
3357 	sk->sk_write_pending	=	0;
3358 	sk->sk_rcvlowat		=	1;
3359 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
3360 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
3361 
3362 	sk->sk_stamp = SK_DEFAULT_STAMP;
3363 #if BITS_PER_LONG==32
3364 	seqlock_init(&sk->sk_stamp_seq);
3365 #endif
3366 	atomic_set(&sk->sk_zckey, 0);
3367 
3368 #ifdef CONFIG_NET_RX_BUSY_POLL
3369 	sk->sk_napi_id		=	0;
3370 	sk->sk_ll_usec		=	READ_ONCE(sysctl_net_busy_read);
3371 #endif
3372 
3373 	sk->sk_max_pacing_rate = ~0UL;
3374 	sk->sk_pacing_rate = ~0UL;
3375 	WRITE_ONCE(sk->sk_pacing_shift, 10);
3376 	sk->sk_incoming_cpu = -1;
3377 	sk->sk_txrehash = SOCK_TXREHASH_DEFAULT;
3378 
3379 	sk_rx_queue_clear(sk);
3380 	/*
3381 	 * Before updating sk_refcnt, we must commit prior changes to memory
3382 	 * (Documentation/RCU/rculist_nulls.rst for details)
3383 	 */
3384 	smp_wmb();
3385 	refcount_set(&sk->sk_refcnt, 1);
3386 	atomic_set(&sk->sk_drops, 0);
3387 }
3388 EXPORT_SYMBOL(sock_init_data);
3389 
3390 void lock_sock_nested(struct sock *sk, int subclass)
3391 {
3392 	/* The sk_lock has mutex_lock() semantics here. */
3393 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3394 
3395 	might_sleep();
3396 	spin_lock_bh(&sk->sk_lock.slock);
3397 	if (sock_owned_by_user_nocheck(sk))
3398 		__lock_sock(sk);
3399 	sk->sk_lock.owned = 1;
3400 	spin_unlock_bh(&sk->sk_lock.slock);
3401 }
3402 EXPORT_SYMBOL(lock_sock_nested);
3403 
3404 void release_sock(struct sock *sk)
3405 {
3406 	spin_lock_bh(&sk->sk_lock.slock);
3407 	if (sk->sk_backlog.tail)
3408 		__release_sock(sk);
3409 
3410 	/* Warning : release_cb() might need to release sk ownership,
3411 	 * ie call sock_release_ownership(sk) before us.
3412 	 */
3413 	if (sk->sk_prot->release_cb)
3414 		sk->sk_prot->release_cb(sk);
3415 
3416 	sock_release_ownership(sk);
3417 	if (waitqueue_active(&sk->sk_lock.wq))
3418 		wake_up(&sk->sk_lock.wq);
3419 	spin_unlock_bh(&sk->sk_lock.slock);
3420 }
3421 EXPORT_SYMBOL(release_sock);
3422 
3423 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3424 {
3425 	might_sleep();
3426 	spin_lock_bh(&sk->sk_lock.slock);
3427 
3428 	if (!sock_owned_by_user_nocheck(sk)) {
3429 		/*
3430 		 * Fast path return with bottom halves disabled and
3431 		 * sock::sk_lock.slock held.
3432 		 *
3433 		 * The 'mutex' is not contended and holding
3434 		 * sock::sk_lock.slock prevents all other lockers to
3435 		 * proceed so the corresponding unlock_sock_fast() can
3436 		 * avoid the slow path of release_sock() completely and
3437 		 * just release slock.
3438 		 *
3439 		 * From a semantical POV this is equivalent to 'acquiring'
3440 		 * the 'mutex', hence the corresponding lockdep
3441 		 * mutex_release() has to happen in the fast path of
3442 		 * unlock_sock_fast().
3443 		 */
3444 		return false;
3445 	}
3446 
3447 	__lock_sock(sk);
3448 	sk->sk_lock.owned = 1;
3449 	__acquire(&sk->sk_lock.slock);
3450 	spin_unlock_bh(&sk->sk_lock.slock);
3451 	return true;
3452 }
3453 EXPORT_SYMBOL(__lock_sock_fast);
3454 
3455 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3456 		   bool timeval, bool time32)
3457 {
3458 	struct sock *sk = sock->sk;
3459 	struct timespec64 ts;
3460 
3461 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3462 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
3463 	if (ts.tv_sec == -1)
3464 		return -ENOENT;
3465 	if (ts.tv_sec == 0) {
3466 		ktime_t kt = ktime_get_real();
3467 		sock_write_timestamp(sk, kt);
3468 		ts = ktime_to_timespec64(kt);
3469 	}
3470 
3471 	if (timeval)
3472 		ts.tv_nsec /= 1000;
3473 
3474 #ifdef CONFIG_COMPAT_32BIT_TIME
3475 	if (time32)
3476 		return put_old_timespec32(&ts, userstamp);
3477 #endif
3478 #ifdef CONFIG_SPARC64
3479 	/* beware of padding in sparc64 timeval */
3480 	if (timeval && !in_compat_syscall()) {
3481 		struct __kernel_old_timeval __user tv = {
3482 			.tv_sec = ts.tv_sec,
3483 			.tv_usec = ts.tv_nsec,
3484 		};
3485 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3486 			return -EFAULT;
3487 		return 0;
3488 	}
3489 #endif
3490 	return put_timespec64(&ts, userstamp);
3491 }
3492 EXPORT_SYMBOL(sock_gettstamp);
3493 
3494 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3495 {
3496 	if (!sock_flag(sk, flag)) {
3497 		unsigned long previous_flags = sk->sk_flags;
3498 
3499 		sock_set_flag(sk, flag);
3500 		/*
3501 		 * we just set one of the two flags which require net
3502 		 * time stamping, but time stamping might have been on
3503 		 * already because of the other one
3504 		 */
3505 		if (sock_needs_netstamp(sk) &&
3506 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3507 			net_enable_timestamp();
3508 	}
3509 }
3510 
3511 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3512 		       int level, int type)
3513 {
3514 	struct sock_exterr_skb *serr;
3515 	struct sk_buff *skb;
3516 	int copied, err;
3517 
3518 	err = -EAGAIN;
3519 	skb = sock_dequeue_err_skb(sk);
3520 	if (skb == NULL)
3521 		goto out;
3522 
3523 	copied = skb->len;
3524 	if (copied > len) {
3525 		msg->msg_flags |= MSG_TRUNC;
3526 		copied = len;
3527 	}
3528 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3529 	if (err)
3530 		goto out_free_skb;
3531 
3532 	sock_recv_timestamp(msg, sk, skb);
3533 
3534 	serr = SKB_EXT_ERR(skb);
3535 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3536 
3537 	msg->msg_flags |= MSG_ERRQUEUE;
3538 	err = copied;
3539 
3540 out_free_skb:
3541 	kfree_skb(skb);
3542 out:
3543 	return err;
3544 }
3545 EXPORT_SYMBOL(sock_recv_errqueue);
3546 
3547 /*
3548  *	Get a socket option on an socket.
3549  *
3550  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3551  *	asynchronous errors should be reported by getsockopt. We assume
3552  *	this means if you specify SO_ERROR (otherwise whats the point of it).
3553  */
3554 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3555 			   char __user *optval, int __user *optlen)
3556 {
3557 	struct sock *sk = sock->sk;
3558 
3559 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3560 }
3561 EXPORT_SYMBOL(sock_common_getsockopt);
3562 
3563 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3564 			int flags)
3565 {
3566 	struct sock *sk = sock->sk;
3567 	int addr_len = 0;
3568 	int err;
3569 
3570 	err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3571 	if (err >= 0)
3572 		msg->msg_namelen = addr_len;
3573 	return err;
3574 }
3575 EXPORT_SYMBOL(sock_common_recvmsg);
3576 
3577 /*
3578  *	Set socket options on an inet socket.
3579  */
3580 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3581 			   sockptr_t optval, unsigned int optlen)
3582 {
3583 	struct sock *sk = sock->sk;
3584 
3585 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3586 }
3587 EXPORT_SYMBOL(sock_common_setsockopt);
3588 
3589 void sk_common_release(struct sock *sk)
3590 {
3591 	if (sk->sk_prot->destroy)
3592 		sk->sk_prot->destroy(sk);
3593 
3594 	/*
3595 	 * Observation: when sk_common_release is called, processes have
3596 	 * no access to socket. But net still has.
3597 	 * Step one, detach it from networking:
3598 	 *
3599 	 * A. Remove from hash tables.
3600 	 */
3601 
3602 	sk->sk_prot->unhash(sk);
3603 
3604 	/*
3605 	 * In this point socket cannot receive new packets, but it is possible
3606 	 * that some packets are in flight because some CPU runs receiver and
3607 	 * did hash table lookup before we unhashed socket. They will achieve
3608 	 * receive queue and will be purged by socket destructor.
3609 	 *
3610 	 * Also we still have packets pending on receive queue and probably,
3611 	 * our own packets waiting in device queues. sock_destroy will drain
3612 	 * receive queue, but transmitted packets will delay socket destruction
3613 	 * until the last reference will be released.
3614 	 */
3615 
3616 	sock_orphan(sk);
3617 
3618 	xfrm_sk_free_policy(sk);
3619 
3620 	sk_refcnt_debug_release(sk);
3621 
3622 	sock_put(sk);
3623 }
3624 EXPORT_SYMBOL(sk_common_release);
3625 
3626 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3627 {
3628 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3629 
3630 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3631 	mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3632 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3633 	mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3634 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3635 	mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3636 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3637 	mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3638 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3639 }
3640 
3641 #ifdef CONFIG_PROC_FS
3642 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3643 
3644 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3645 {
3646 	int cpu, idx = prot->inuse_idx;
3647 	int res = 0;
3648 
3649 	for_each_possible_cpu(cpu)
3650 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3651 
3652 	return res >= 0 ? res : 0;
3653 }
3654 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3655 
3656 int sock_inuse_get(struct net *net)
3657 {
3658 	int cpu, res = 0;
3659 
3660 	for_each_possible_cpu(cpu)
3661 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3662 
3663 	return res;
3664 }
3665 
3666 EXPORT_SYMBOL_GPL(sock_inuse_get);
3667 
3668 static int __net_init sock_inuse_init_net(struct net *net)
3669 {
3670 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3671 	if (net->core.prot_inuse == NULL)
3672 		return -ENOMEM;
3673 	return 0;
3674 }
3675 
3676 static void __net_exit sock_inuse_exit_net(struct net *net)
3677 {
3678 	free_percpu(net->core.prot_inuse);
3679 }
3680 
3681 static struct pernet_operations net_inuse_ops = {
3682 	.init = sock_inuse_init_net,
3683 	.exit = sock_inuse_exit_net,
3684 };
3685 
3686 static __init int net_inuse_init(void)
3687 {
3688 	if (register_pernet_subsys(&net_inuse_ops))
3689 		panic("Cannot initialize net inuse counters");
3690 
3691 	return 0;
3692 }
3693 
3694 core_initcall(net_inuse_init);
3695 
3696 static int assign_proto_idx(struct proto *prot)
3697 {
3698 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3699 
3700 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3701 		pr_err("PROTO_INUSE_NR exhausted\n");
3702 		return -ENOSPC;
3703 	}
3704 
3705 	set_bit(prot->inuse_idx, proto_inuse_idx);
3706 	return 0;
3707 }
3708 
3709 static void release_proto_idx(struct proto *prot)
3710 {
3711 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3712 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3713 }
3714 #else
3715 static inline int assign_proto_idx(struct proto *prot)
3716 {
3717 	return 0;
3718 }
3719 
3720 static inline void release_proto_idx(struct proto *prot)
3721 {
3722 }
3723 
3724 #endif
3725 
3726 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3727 {
3728 	if (!twsk_prot)
3729 		return;
3730 	kfree(twsk_prot->twsk_slab_name);
3731 	twsk_prot->twsk_slab_name = NULL;
3732 	kmem_cache_destroy(twsk_prot->twsk_slab);
3733 	twsk_prot->twsk_slab = NULL;
3734 }
3735 
3736 static int tw_prot_init(const struct proto *prot)
3737 {
3738 	struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3739 
3740 	if (!twsk_prot)
3741 		return 0;
3742 
3743 	twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3744 					      prot->name);
3745 	if (!twsk_prot->twsk_slab_name)
3746 		return -ENOMEM;
3747 
3748 	twsk_prot->twsk_slab =
3749 		kmem_cache_create(twsk_prot->twsk_slab_name,
3750 				  twsk_prot->twsk_obj_size, 0,
3751 				  SLAB_ACCOUNT | prot->slab_flags,
3752 				  NULL);
3753 	if (!twsk_prot->twsk_slab) {
3754 		pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3755 			prot->name);
3756 		return -ENOMEM;
3757 	}
3758 
3759 	return 0;
3760 }
3761 
3762 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3763 {
3764 	if (!rsk_prot)
3765 		return;
3766 	kfree(rsk_prot->slab_name);
3767 	rsk_prot->slab_name = NULL;
3768 	kmem_cache_destroy(rsk_prot->slab);
3769 	rsk_prot->slab = NULL;
3770 }
3771 
3772 static int req_prot_init(const struct proto *prot)
3773 {
3774 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3775 
3776 	if (!rsk_prot)
3777 		return 0;
3778 
3779 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3780 					prot->name);
3781 	if (!rsk_prot->slab_name)
3782 		return -ENOMEM;
3783 
3784 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3785 					   rsk_prot->obj_size, 0,
3786 					   SLAB_ACCOUNT | prot->slab_flags,
3787 					   NULL);
3788 
3789 	if (!rsk_prot->slab) {
3790 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3791 			prot->name);
3792 		return -ENOMEM;
3793 	}
3794 	return 0;
3795 }
3796 
3797 int proto_register(struct proto *prot, int alloc_slab)
3798 {
3799 	int ret = -ENOBUFS;
3800 
3801 	if (prot->memory_allocated && !prot->sysctl_mem) {
3802 		pr_err("%s: missing sysctl_mem\n", prot->name);
3803 		return -EINVAL;
3804 	}
3805 	if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
3806 		pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
3807 		return -EINVAL;
3808 	}
3809 	if (alloc_slab) {
3810 		prot->slab = kmem_cache_create_usercopy(prot->name,
3811 					prot->obj_size, 0,
3812 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3813 					prot->slab_flags,
3814 					prot->useroffset, prot->usersize,
3815 					NULL);
3816 
3817 		if (prot->slab == NULL) {
3818 			pr_crit("%s: Can't create sock SLAB cache!\n",
3819 				prot->name);
3820 			goto out;
3821 		}
3822 
3823 		if (req_prot_init(prot))
3824 			goto out_free_request_sock_slab;
3825 
3826 		if (tw_prot_init(prot))
3827 			goto out_free_timewait_sock_slab;
3828 	}
3829 
3830 	mutex_lock(&proto_list_mutex);
3831 	ret = assign_proto_idx(prot);
3832 	if (ret) {
3833 		mutex_unlock(&proto_list_mutex);
3834 		goto out_free_timewait_sock_slab;
3835 	}
3836 	list_add(&prot->node, &proto_list);
3837 	mutex_unlock(&proto_list_mutex);
3838 	return ret;
3839 
3840 out_free_timewait_sock_slab:
3841 	if (alloc_slab)
3842 		tw_prot_cleanup(prot->twsk_prot);
3843 out_free_request_sock_slab:
3844 	if (alloc_slab) {
3845 		req_prot_cleanup(prot->rsk_prot);
3846 
3847 		kmem_cache_destroy(prot->slab);
3848 		prot->slab = NULL;
3849 	}
3850 out:
3851 	return ret;
3852 }
3853 EXPORT_SYMBOL(proto_register);
3854 
3855 void proto_unregister(struct proto *prot)
3856 {
3857 	mutex_lock(&proto_list_mutex);
3858 	release_proto_idx(prot);
3859 	list_del(&prot->node);
3860 	mutex_unlock(&proto_list_mutex);
3861 
3862 	kmem_cache_destroy(prot->slab);
3863 	prot->slab = NULL;
3864 
3865 	req_prot_cleanup(prot->rsk_prot);
3866 	tw_prot_cleanup(prot->twsk_prot);
3867 }
3868 EXPORT_SYMBOL(proto_unregister);
3869 
3870 int sock_load_diag_module(int family, int protocol)
3871 {
3872 	if (!protocol) {
3873 		if (!sock_is_registered(family))
3874 			return -ENOENT;
3875 
3876 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3877 				      NETLINK_SOCK_DIAG, family);
3878 	}
3879 
3880 #ifdef CONFIG_INET
3881 	if (family == AF_INET &&
3882 	    protocol != IPPROTO_RAW &&
3883 	    protocol < MAX_INET_PROTOS &&
3884 	    !rcu_access_pointer(inet_protos[protocol]))
3885 		return -ENOENT;
3886 #endif
3887 
3888 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3889 			      NETLINK_SOCK_DIAG, family, protocol);
3890 }
3891 EXPORT_SYMBOL(sock_load_diag_module);
3892 
3893 #ifdef CONFIG_PROC_FS
3894 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3895 	__acquires(proto_list_mutex)
3896 {
3897 	mutex_lock(&proto_list_mutex);
3898 	return seq_list_start_head(&proto_list, *pos);
3899 }
3900 
3901 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3902 {
3903 	return seq_list_next(v, &proto_list, pos);
3904 }
3905 
3906 static void proto_seq_stop(struct seq_file *seq, void *v)
3907 	__releases(proto_list_mutex)
3908 {
3909 	mutex_unlock(&proto_list_mutex);
3910 }
3911 
3912 static char proto_method_implemented(const void *method)
3913 {
3914 	return method == NULL ? 'n' : 'y';
3915 }
3916 static long sock_prot_memory_allocated(struct proto *proto)
3917 {
3918 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3919 }
3920 
3921 static const char *sock_prot_memory_pressure(struct proto *proto)
3922 {
3923 	return proto->memory_pressure != NULL ?
3924 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3925 }
3926 
3927 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3928 {
3929 
3930 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
3931 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3932 		   proto->name,
3933 		   proto->obj_size,
3934 		   sock_prot_inuse_get(seq_file_net(seq), proto),
3935 		   sock_prot_memory_allocated(proto),
3936 		   sock_prot_memory_pressure(proto),
3937 		   proto->max_header,
3938 		   proto->slab == NULL ? "no" : "yes",
3939 		   module_name(proto->owner),
3940 		   proto_method_implemented(proto->close),
3941 		   proto_method_implemented(proto->connect),
3942 		   proto_method_implemented(proto->disconnect),
3943 		   proto_method_implemented(proto->accept),
3944 		   proto_method_implemented(proto->ioctl),
3945 		   proto_method_implemented(proto->init),
3946 		   proto_method_implemented(proto->destroy),
3947 		   proto_method_implemented(proto->shutdown),
3948 		   proto_method_implemented(proto->setsockopt),
3949 		   proto_method_implemented(proto->getsockopt),
3950 		   proto_method_implemented(proto->sendmsg),
3951 		   proto_method_implemented(proto->recvmsg),
3952 		   proto_method_implemented(proto->sendpage),
3953 		   proto_method_implemented(proto->bind),
3954 		   proto_method_implemented(proto->backlog_rcv),
3955 		   proto_method_implemented(proto->hash),
3956 		   proto_method_implemented(proto->unhash),
3957 		   proto_method_implemented(proto->get_port),
3958 		   proto_method_implemented(proto->enter_memory_pressure));
3959 }
3960 
3961 static int proto_seq_show(struct seq_file *seq, void *v)
3962 {
3963 	if (v == &proto_list)
3964 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3965 			   "protocol",
3966 			   "size",
3967 			   "sockets",
3968 			   "memory",
3969 			   "press",
3970 			   "maxhdr",
3971 			   "slab",
3972 			   "module",
3973 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3974 	else
3975 		proto_seq_printf(seq, list_entry(v, struct proto, node));
3976 	return 0;
3977 }
3978 
3979 static const struct seq_operations proto_seq_ops = {
3980 	.start  = proto_seq_start,
3981 	.next   = proto_seq_next,
3982 	.stop   = proto_seq_stop,
3983 	.show   = proto_seq_show,
3984 };
3985 
3986 static __net_init int proto_init_net(struct net *net)
3987 {
3988 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
3989 			sizeof(struct seq_net_private)))
3990 		return -ENOMEM;
3991 
3992 	return 0;
3993 }
3994 
3995 static __net_exit void proto_exit_net(struct net *net)
3996 {
3997 	remove_proc_entry("protocols", net->proc_net);
3998 }
3999 
4000 
4001 static __net_initdata struct pernet_operations proto_net_ops = {
4002 	.init = proto_init_net,
4003 	.exit = proto_exit_net,
4004 };
4005 
4006 static int __init proto_init(void)
4007 {
4008 	return register_pernet_subsys(&proto_net_ops);
4009 }
4010 
4011 subsys_initcall(proto_init);
4012 
4013 #endif /* PROC_FS */
4014 
4015 #ifdef CONFIG_NET_RX_BUSY_POLL
4016 bool sk_busy_loop_end(void *p, unsigned long start_time)
4017 {
4018 	struct sock *sk = p;
4019 
4020 	return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
4021 	       sk_busy_loop_timeout(sk, start_time);
4022 }
4023 EXPORT_SYMBOL(sk_busy_loop_end);
4024 #endif /* CONFIG_NET_RX_BUSY_POLL */
4025 
4026 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4027 {
4028 	if (!sk->sk_prot->bind_add)
4029 		return -EOPNOTSUPP;
4030 	return sk->sk_prot->bind_add(sk, addr, addr_len);
4031 }
4032 EXPORT_SYMBOL(sock_bind_add);
4033