xref: /openbmc/linux/net/core/sock.c (revision 59bd9ded)
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 
117 #include <linux/uaccess.h>
118 
119 #include <linux/netdevice.h>
120 #include <net/protocol.h>
121 #include <linux/skbuff.h>
122 #include <net/net_namespace.h>
123 #include <net/request_sock.h>
124 #include <net/sock.h>
125 #include <linux/net_tstamp.h>
126 #include <net/xfrm.h>
127 #include <linux/ipsec.h>
128 #include <net/cls_cgroup.h>
129 #include <net/netprio_cgroup.h>
130 #include <linux/sock_diag.h>
131 
132 #include <linux/filter.h>
133 #include <net/sock_reuseport.h>
134 #include <net/bpf_sk_storage.h>
135 
136 #include <trace/events/sock.h>
137 
138 #include <net/tcp.h>
139 #include <net/busy_poll.h>
140 
141 static DEFINE_MUTEX(proto_list_mutex);
142 static LIST_HEAD(proto_list);
143 
144 static void sock_inuse_add(struct net *net, int val);
145 
146 /**
147  * sk_ns_capable - General socket capability test
148  * @sk: Socket to use a capability on or through
149  * @user_ns: The user namespace of the capability to use
150  * @cap: The capability to use
151  *
152  * Test to see if the opener of the socket had when the socket was
153  * created and the current process has the capability @cap in the user
154  * namespace @user_ns.
155  */
156 bool sk_ns_capable(const struct sock *sk,
157 		   struct user_namespace *user_ns, int cap)
158 {
159 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
160 		ns_capable(user_ns, cap);
161 }
162 EXPORT_SYMBOL(sk_ns_capable);
163 
164 /**
165  * sk_capable - Socket global capability test
166  * @sk: Socket to use a capability on or through
167  * @cap: The global capability to use
168  *
169  * Test to see if the opener of the socket had when the socket was
170  * created and the current process has the capability @cap in all user
171  * namespaces.
172  */
173 bool sk_capable(const struct sock *sk, int cap)
174 {
175 	return sk_ns_capable(sk, &init_user_ns, cap);
176 }
177 EXPORT_SYMBOL(sk_capable);
178 
179 /**
180  * sk_net_capable - Network namespace socket capability test
181  * @sk: Socket to use a capability on or through
182  * @cap: The capability to use
183  *
184  * Test to see if the opener of the socket had when the socket was created
185  * and the current process has the capability @cap over the network namespace
186  * the socket is a member of.
187  */
188 bool sk_net_capable(const struct sock *sk, int cap)
189 {
190 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
191 }
192 EXPORT_SYMBOL(sk_net_capable);
193 
194 /*
195  * Each address family might have different locking rules, so we have
196  * one slock key per address family and separate keys for internal and
197  * userspace sockets.
198  */
199 static struct lock_class_key af_family_keys[AF_MAX];
200 static struct lock_class_key af_family_kern_keys[AF_MAX];
201 static struct lock_class_key af_family_slock_keys[AF_MAX];
202 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
203 
204 /*
205  * Make lock validator output more readable. (we pre-construct these
206  * strings build-time, so that runtime initialization of socket
207  * locks is fast):
208  */
209 
210 #define _sock_locks(x)						  \
211   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
212   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
213   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
214   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
215   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
216   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
217   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
218   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
219   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
220   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
221   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
222   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
223   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
224   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
225   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
226   x "AF_MAX"
227 
228 static const char *const af_family_key_strings[AF_MAX+1] = {
229 	_sock_locks("sk_lock-")
230 };
231 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
232 	_sock_locks("slock-")
233 };
234 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
235 	_sock_locks("clock-")
236 };
237 
238 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
239 	_sock_locks("k-sk_lock-")
240 };
241 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
242 	_sock_locks("k-slock-")
243 };
244 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
245 	_sock_locks("k-clock-")
246 };
247 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
248 	_sock_locks("rlock-")
249 };
250 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
251 	_sock_locks("wlock-")
252 };
253 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
254 	_sock_locks("elock-")
255 };
256 
257 /*
258  * sk_callback_lock and sk queues locking rules are per-address-family,
259  * so split the lock classes by using a per-AF key:
260  */
261 static struct lock_class_key af_callback_keys[AF_MAX];
262 static struct lock_class_key af_rlock_keys[AF_MAX];
263 static struct lock_class_key af_wlock_keys[AF_MAX];
264 static struct lock_class_key af_elock_keys[AF_MAX];
265 static struct lock_class_key af_kern_callback_keys[AF_MAX];
266 
267 /* Run time adjustable parameters. */
268 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
269 EXPORT_SYMBOL(sysctl_wmem_max);
270 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
271 EXPORT_SYMBOL(sysctl_rmem_max);
272 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
273 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
274 
275 /* Maximal space eaten by iovec or ancillary data plus some space */
276 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
277 EXPORT_SYMBOL(sysctl_optmem_max);
278 
279 int sysctl_tstamp_allow_data __read_mostly = 1;
280 
281 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
282 EXPORT_SYMBOL_GPL(memalloc_socks_key);
283 
284 /**
285  * sk_set_memalloc - sets %SOCK_MEMALLOC
286  * @sk: socket to set it on
287  *
288  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
289  * It's the responsibility of the admin to adjust min_free_kbytes
290  * to meet the requirements
291  */
292 void sk_set_memalloc(struct sock *sk)
293 {
294 	sock_set_flag(sk, SOCK_MEMALLOC);
295 	sk->sk_allocation |= __GFP_MEMALLOC;
296 	static_branch_inc(&memalloc_socks_key);
297 }
298 EXPORT_SYMBOL_GPL(sk_set_memalloc);
299 
300 void sk_clear_memalloc(struct sock *sk)
301 {
302 	sock_reset_flag(sk, SOCK_MEMALLOC);
303 	sk->sk_allocation &= ~__GFP_MEMALLOC;
304 	static_branch_dec(&memalloc_socks_key);
305 
306 	/*
307 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
308 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
309 	 * it has rmem allocations due to the last swapfile being deactivated
310 	 * but there is a risk that the socket is unusable due to exceeding
311 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
312 	 */
313 	sk_mem_reclaim(sk);
314 }
315 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
316 
317 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
318 {
319 	int ret;
320 	unsigned int noreclaim_flag;
321 
322 	/* these should have been dropped before queueing */
323 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
324 
325 	noreclaim_flag = memalloc_noreclaim_save();
326 	ret = sk->sk_backlog_rcv(sk, skb);
327 	memalloc_noreclaim_restore(noreclaim_flag);
328 
329 	return ret;
330 }
331 EXPORT_SYMBOL(__sk_backlog_rcv);
332 
333 static int sock_get_timeout(long timeo, void *optval, bool old_timeval)
334 {
335 	struct __kernel_sock_timeval tv;
336 	int size;
337 
338 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
339 		tv.tv_sec = 0;
340 		tv.tv_usec = 0;
341 	} else {
342 		tv.tv_sec = timeo / HZ;
343 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
344 	}
345 
346 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
347 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
348 		*(struct old_timeval32 *)optval = tv32;
349 		return sizeof(tv32);
350 	}
351 
352 	if (old_timeval) {
353 		struct __kernel_old_timeval old_tv;
354 		old_tv.tv_sec = tv.tv_sec;
355 		old_tv.tv_usec = tv.tv_usec;
356 		*(struct __kernel_old_timeval *)optval = old_tv;
357 		size = sizeof(old_tv);
358 	} else {
359 		*(struct __kernel_sock_timeval *)optval = tv;
360 		size = sizeof(tv);
361 	}
362 
363 	return size;
364 }
365 
366 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen, bool old_timeval)
367 {
368 	struct __kernel_sock_timeval tv;
369 
370 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
371 		struct old_timeval32 tv32;
372 
373 		if (optlen < sizeof(tv32))
374 			return -EINVAL;
375 
376 		if (copy_from_user(&tv32, optval, sizeof(tv32)))
377 			return -EFAULT;
378 		tv.tv_sec = tv32.tv_sec;
379 		tv.tv_usec = tv32.tv_usec;
380 	} else if (old_timeval) {
381 		struct __kernel_old_timeval old_tv;
382 
383 		if (optlen < sizeof(old_tv))
384 			return -EINVAL;
385 		if (copy_from_user(&old_tv, optval, sizeof(old_tv)))
386 			return -EFAULT;
387 		tv.tv_sec = old_tv.tv_sec;
388 		tv.tv_usec = old_tv.tv_usec;
389 	} else {
390 		if (optlen < sizeof(tv))
391 			return -EINVAL;
392 		if (copy_from_user(&tv, optval, sizeof(tv)))
393 			return -EFAULT;
394 	}
395 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
396 		return -EDOM;
397 
398 	if (tv.tv_sec < 0) {
399 		static int warned __read_mostly;
400 
401 		*timeo_p = 0;
402 		if (warned < 10 && net_ratelimit()) {
403 			warned++;
404 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
405 				__func__, current->comm, task_pid_nr(current));
406 		}
407 		return 0;
408 	}
409 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
410 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
411 		return 0;
412 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
413 		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
414 	return 0;
415 }
416 
417 static void sock_warn_obsolete_bsdism(const char *name)
418 {
419 	static int warned;
420 	static char warncomm[TASK_COMM_LEN];
421 	if (strcmp(warncomm, current->comm) && warned < 5) {
422 		strcpy(warncomm,  current->comm);
423 		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
424 			warncomm, name);
425 		warned++;
426 	}
427 }
428 
429 static bool sock_needs_netstamp(const struct sock *sk)
430 {
431 	switch (sk->sk_family) {
432 	case AF_UNSPEC:
433 	case AF_UNIX:
434 		return false;
435 	default:
436 		return true;
437 	}
438 }
439 
440 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
441 {
442 	if (sk->sk_flags & flags) {
443 		sk->sk_flags &= ~flags;
444 		if (sock_needs_netstamp(sk) &&
445 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
446 			net_disable_timestamp();
447 	}
448 }
449 
450 
451 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
452 {
453 	unsigned long flags;
454 	struct sk_buff_head *list = &sk->sk_receive_queue;
455 
456 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
457 		atomic_inc(&sk->sk_drops);
458 		trace_sock_rcvqueue_full(sk, skb);
459 		return -ENOMEM;
460 	}
461 
462 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
463 		atomic_inc(&sk->sk_drops);
464 		return -ENOBUFS;
465 	}
466 
467 	skb->dev = NULL;
468 	skb_set_owner_r(skb, sk);
469 
470 	/* we escape from rcu protected region, make sure we dont leak
471 	 * a norefcounted dst
472 	 */
473 	skb_dst_force(skb);
474 
475 	spin_lock_irqsave(&list->lock, flags);
476 	sock_skb_set_dropcount(sk, skb);
477 	__skb_queue_tail(list, skb);
478 	spin_unlock_irqrestore(&list->lock, flags);
479 
480 	if (!sock_flag(sk, SOCK_DEAD))
481 		sk->sk_data_ready(sk);
482 	return 0;
483 }
484 EXPORT_SYMBOL(__sock_queue_rcv_skb);
485 
486 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
487 {
488 	int err;
489 
490 	err = sk_filter(sk, skb);
491 	if (err)
492 		return err;
493 
494 	return __sock_queue_rcv_skb(sk, skb);
495 }
496 EXPORT_SYMBOL(sock_queue_rcv_skb);
497 
498 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
499 		     const int nested, unsigned int trim_cap, bool refcounted)
500 {
501 	int rc = NET_RX_SUCCESS;
502 
503 	if (sk_filter_trim_cap(sk, skb, trim_cap))
504 		goto discard_and_relse;
505 
506 	skb->dev = NULL;
507 
508 	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
509 		atomic_inc(&sk->sk_drops);
510 		goto discard_and_relse;
511 	}
512 	if (nested)
513 		bh_lock_sock_nested(sk);
514 	else
515 		bh_lock_sock(sk);
516 	if (!sock_owned_by_user(sk)) {
517 		/*
518 		 * trylock + unlock semantics:
519 		 */
520 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
521 
522 		rc = sk_backlog_rcv(sk, skb);
523 
524 		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
525 	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
526 		bh_unlock_sock(sk);
527 		atomic_inc(&sk->sk_drops);
528 		goto discard_and_relse;
529 	}
530 
531 	bh_unlock_sock(sk);
532 out:
533 	if (refcounted)
534 		sock_put(sk);
535 	return rc;
536 discard_and_relse:
537 	kfree_skb(skb);
538 	goto out;
539 }
540 EXPORT_SYMBOL(__sk_receive_skb);
541 
542 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
543 {
544 	struct dst_entry *dst = __sk_dst_get(sk);
545 
546 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
547 		sk_tx_queue_clear(sk);
548 		sk->sk_dst_pending_confirm = 0;
549 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
550 		dst_release(dst);
551 		return NULL;
552 	}
553 
554 	return dst;
555 }
556 EXPORT_SYMBOL(__sk_dst_check);
557 
558 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
559 {
560 	struct dst_entry *dst = sk_dst_get(sk);
561 
562 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
563 		sk_dst_reset(sk);
564 		dst_release(dst);
565 		return NULL;
566 	}
567 
568 	return dst;
569 }
570 EXPORT_SYMBOL(sk_dst_check);
571 
572 static int sock_setbindtodevice_locked(struct sock *sk, int ifindex)
573 {
574 	int ret = -ENOPROTOOPT;
575 #ifdef CONFIG_NETDEVICES
576 	struct net *net = sock_net(sk);
577 
578 	/* Sorry... */
579 	ret = -EPERM;
580 	if (!ns_capable(net->user_ns, CAP_NET_RAW))
581 		goto out;
582 
583 	ret = -EINVAL;
584 	if (ifindex < 0)
585 		goto out;
586 
587 	sk->sk_bound_dev_if = ifindex;
588 	if (sk->sk_prot->rehash)
589 		sk->sk_prot->rehash(sk);
590 	sk_dst_reset(sk);
591 
592 	ret = 0;
593 
594 out:
595 #endif
596 
597 	return ret;
598 }
599 
600 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
601 				int optlen)
602 {
603 	int ret = -ENOPROTOOPT;
604 #ifdef CONFIG_NETDEVICES
605 	struct net *net = sock_net(sk);
606 	char devname[IFNAMSIZ];
607 	int index;
608 
609 	ret = -EINVAL;
610 	if (optlen < 0)
611 		goto out;
612 
613 	/* Bind this socket to a particular device like "eth0",
614 	 * as specified in the passed interface name. If the
615 	 * name is "" or the option length is zero the socket
616 	 * is not bound.
617 	 */
618 	if (optlen > IFNAMSIZ - 1)
619 		optlen = IFNAMSIZ - 1;
620 	memset(devname, 0, sizeof(devname));
621 
622 	ret = -EFAULT;
623 	if (copy_from_user(devname, optval, optlen))
624 		goto out;
625 
626 	index = 0;
627 	if (devname[0] != '\0') {
628 		struct net_device *dev;
629 
630 		rcu_read_lock();
631 		dev = dev_get_by_name_rcu(net, devname);
632 		if (dev)
633 			index = dev->ifindex;
634 		rcu_read_unlock();
635 		ret = -ENODEV;
636 		if (!dev)
637 			goto out;
638 	}
639 
640 	lock_sock(sk);
641 	ret = sock_setbindtodevice_locked(sk, index);
642 	release_sock(sk);
643 
644 out:
645 #endif
646 
647 	return ret;
648 }
649 
650 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
651 				int __user *optlen, int len)
652 {
653 	int ret = -ENOPROTOOPT;
654 #ifdef CONFIG_NETDEVICES
655 	struct net *net = sock_net(sk);
656 	char devname[IFNAMSIZ];
657 
658 	if (sk->sk_bound_dev_if == 0) {
659 		len = 0;
660 		goto zero;
661 	}
662 
663 	ret = -EINVAL;
664 	if (len < IFNAMSIZ)
665 		goto out;
666 
667 	ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
668 	if (ret)
669 		goto out;
670 
671 	len = strlen(devname) + 1;
672 
673 	ret = -EFAULT;
674 	if (copy_to_user(optval, devname, len))
675 		goto out;
676 
677 zero:
678 	ret = -EFAULT;
679 	if (put_user(len, optlen))
680 		goto out;
681 
682 	ret = 0;
683 
684 out:
685 #endif
686 
687 	return ret;
688 }
689 
690 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
691 {
692 	if (valbool)
693 		sock_set_flag(sk, bit);
694 	else
695 		sock_reset_flag(sk, bit);
696 }
697 
698 bool sk_mc_loop(struct sock *sk)
699 {
700 	if (dev_recursion_level())
701 		return false;
702 	if (!sk)
703 		return true;
704 	switch (sk->sk_family) {
705 	case AF_INET:
706 		return inet_sk(sk)->mc_loop;
707 #if IS_ENABLED(CONFIG_IPV6)
708 	case AF_INET6:
709 		return inet6_sk(sk)->mc_loop;
710 #endif
711 	}
712 	WARN_ON(1);
713 	return true;
714 }
715 EXPORT_SYMBOL(sk_mc_loop);
716 
717 /*
718  *	This is meant for all protocols to use and covers goings on
719  *	at the socket level. Everything here is generic.
720  */
721 
722 int sock_setsockopt(struct socket *sock, int level, int optname,
723 		    char __user *optval, unsigned int optlen)
724 {
725 	struct sock_txtime sk_txtime;
726 	struct sock *sk = sock->sk;
727 	int val;
728 	int valbool;
729 	struct linger ling;
730 	int ret = 0;
731 
732 	/*
733 	 *	Options without arguments
734 	 */
735 
736 	if (optname == SO_BINDTODEVICE)
737 		return sock_setbindtodevice(sk, optval, optlen);
738 
739 	if (optlen < sizeof(int))
740 		return -EINVAL;
741 
742 	if (get_user(val, (int __user *)optval))
743 		return -EFAULT;
744 
745 	valbool = val ? 1 : 0;
746 
747 	lock_sock(sk);
748 
749 	switch (optname) {
750 	case SO_DEBUG:
751 		if (val && !capable(CAP_NET_ADMIN))
752 			ret = -EACCES;
753 		else
754 			sock_valbool_flag(sk, SOCK_DBG, valbool);
755 		break;
756 	case SO_REUSEADDR:
757 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
758 		break;
759 	case SO_REUSEPORT:
760 		sk->sk_reuseport = valbool;
761 		break;
762 	case SO_TYPE:
763 	case SO_PROTOCOL:
764 	case SO_DOMAIN:
765 	case SO_ERROR:
766 		ret = -ENOPROTOOPT;
767 		break;
768 	case SO_DONTROUTE:
769 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
770 		sk_dst_reset(sk);
771 		break;
772 	case SO_BROADCAST:
773 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
774 		break;
775 	case SO_SNDBUF:
776 		/* Don't error on this BSD doesn't and if you think
777 		 * about it this is right. Otherwise apps have to
778 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
779 		 * are treated in BSD as hints
780 		 */
781 		val = min_t(u32, val, sysctl_wmem_max);
782 set_sndbuf:
783 		/* Ensure val * 2 fits into an int, to prevent max_t()
784 		 * from treating it as a negative value.
785 		 */
786 		val = min_t(int, val, INT_MAX / 2);
787 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
788 		sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
789 		/* Wake up sending tasks if we upped the value. */
790 		sk->sk_write_space(sk);
791 		break;
792 
793 	case SO_SNDBUFFORCE:
794 		if (!capable(CAP_NET_ADMIN)) {
795 			ret = -EPERM;
796 			break;
797 		}
798 
799 		/* No negative values (to prevent underflow, as val will be
800 		 * multiplied by 2).
801 		 */
802 		if (val < 0)
803 			val = 0;
804 		goto set_sndbuf;
805 
806 	case SO_RCVBUF:
807 		/* Don't error on this BSD doesn't and if you think
808 		 * about it this is right. Otherwise apps have to
809 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
810 		 * are treated in BSD as hints
811 		 */
812 		val = min_t(u32, val, sysctl_rmem_max);
813 set_rcvbuf:
814 		/* Ensure val * 2 fits into an int, to prevent max_t()
815 		 * from treating it as a negative value.
816 		 */
817 		val = min_t(int, val, INT_MAX / 2);
818 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
819 		/*
820 		 * We double it on the way in to account for
821 		 * "struct sk_buff" etc. overhead.   Applications
822 		 * assume that the SO_RCVBUF setting they make will
823 		 * allow that much actual data to be received on that
824 		 * socket.
825 		 *
826 		 * Applications are unaware that "struct sk_buff" and
827 		 * other overheads allocate from the receive buffer
828 		 * during socket buffer allocation.
829 		 *
830 		 * And after considering the possible alternatives,
831 		 * returning the value we actually used in getsockopt
832 		 * is the most desirable behavior.
833 		 */
834 		sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
835 		break;
836 
837 	case SO_RCVBUFFORCE:
838 		if (!capable(CAP_NET_ADMIN)) {
839 			ret = -EPERM;
840 			break;
841 		}
842 
843 		/* No negative values (to prevent underflow, as val will be
844 		 * multiplied by 2).
845 		 */
846 		if (val < 0)
847 			val = 0;
848 		goto set_rcvbuf;
849 
850 	case SO_KEEPALIVE:
851 		if (sk->sk_prot->keepalive)
852 			sk->sk_prot->keepalive(sk, valbool);
853 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
854 		break;
855 
856 	case SO_OOBINLINE:
857 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
858 		break;
859 
860 	case SO_NO_CHECK:
861 		sk->sk_no_check_tx = valbool;
862 		break;
863 
864 	case SO_PRIORITY:
865 		if ((val >= 0 && val <= 6) ||
866 		    ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
867 			sk->sk_priority = val;
868 		else
869 			ret = -EPERM;
870 		break;
871 
872 	case SO_LINGER:
873 		if (optlen < sizeof(ling)) {
874 			ret = -EINVAL;	/* 1003.1g */
875 			break;
876 		}
877 		if (copy_from_user(&ling, optval, sizeof(ling))) {
878 			ret = -EFAULT;
879 			break;
880 		}
881 		if (!ling.l_onoff)
882 			sock_reset_flag(sk, SOCK_LINGER);
883 		else {
884 #if (BITS_PER_LONG == 32)
885 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
886 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
887 			else
888 #endif
889 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
890 			sock_set_flag(sk, SOCK_LINGER);
891 		}
892 		break;
893 
894 	case SO_BSDCOMPAT:
895 		sock_warn_obsolete_bsdism("setsockopt");
896 		break;
897 
898 	case SO_PASSCRED:
899 		if (valbool)
900 			set_bit(SOCK_PASSCRED, &sock->flags);
901 		else
902 			clear_bit(SOCK_PASSCRED, &sock->flags);
903 		break;
904 
905 	case SO_TIMESTAMP_OLD:
906 	case SO_TIMESTAMP_NEW:
907 	case SO_TIMESTAMPNS_OLD:
908 	case SO_TIMESTAMPNS_NEW:
909 		if (valbool)  {
910 			if (optname == SO_TIMESTAMP_NEW || optname == SO_TIMESTAMPNS_NEW)
911 				sock_set_flag(sk, SOCK_TSTAMP_NEW);
912 			else
913 				sock_reset_flag(sk, SOCK_TSTAMP_NEW);
914 
915 			if (optname == SO_TIMESTAMP_OLD || optname == SO_TIMESTAMP_NEW)
916 				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
917 			else
918 				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
919 			sock_set_flag(sk, SOCK_RCVTSTAMP);
920 			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
921 		} else {
922 			sock_reset_flag(sk, SOCK_RCVTSTAMP);
923 			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
924 			sock_reset_flag(sk, SOCK_TSTAMP_NEW);
925 		}
926 		break;
927 
928 	case SO_TIMESTAMPING_NEW:
929 		sock_set_flag(sk, SOCK_TSTAMP_NEW);
930 		/* fall through */
931 	case SO_TIMESTAMPING_OLD:
932 		if (val & ~SOF_TIMESTAMPING_MASK) {
933 			ret = -EINVAL;
934 			break;
935 		}
936 
937 		if (val & SOF_TIMESTAMPING_OPT_ID &&
938 		    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
939 			if (sk->sk_protocol == IPPROTO_TCP &&
940 			    sk->sk_type == SOCK_STREAM) {
941 				if ((1 << sk->sk_state) &
942 				    (TCPF_CLOSE | TCPF_LISTEN)) {
943 					ret = -EINVAL;
944 					break;
945 				}
946 				sk->sk_tskey = tcp_sk(sk)->snd_una;
947 			} else {
948 				sk->sk_tskey = 0;
949 			}
950 		}
951 
952 		if (val & SOF_TIMESTAMPING_OPT_STATS &&
953 		    !(val & SOF_TIMESTAMPING_OPT_TSONLY)) {
954 			ret = -EINVAL;
955 			break;
956 		}
957 
958 		sk->sk_tsflags = val;
959 		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
960 			sock_enable_timestamp(sk,
961 					      SOCK_TIMESTAMPING_RX_SOFTWARE);
962 		else {
963 			if (optname == SO_TIMESTAMPING_NEW)
964 				sock_reset_flag(sk, SOCK_TSTAMP_NEW);
965 
966 			sock_disable_timestamp(sk,
967 					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
968 		}
969 		break;
970 
971 	case SO_RCVLOWAT:
972 		if (val < 0)
973 			val = INT_MAX;
974 		if (sock->ops->set_rcvlowat)
975 			ret = sock->ops->set_rcvlowat(sk, val);
976 		else
977 			sk->sk_rcvlowat = val ? : 1;
978 		break;
979 
980 	case SO_RCVTIMEO_OLD:
981 	case SO_RCVTIMEO_NEW:
982 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen, optname == SO_RCVTIMEO_OLD);
983 		break;
984 
985 	case SO_SNDTIMEO_OLD:
986 	case SO_SNDTIMEO_NEW:
987 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen, optname == SO_SNDTIMEO_OLD);
988 		break;
989 
990 	case SO_ATTACH_FILTER:
991 		ret = -EINVAL;
992 		if (optlen == sizeof(struct sock_fprog)) {
993 			struct sock_fprog fprog;
994 
995 			ret = -EFAULT;
996 			if (copy_from_user(&fprog, optval, sizeof(fprog)))
997 				break;
998 
999 			ret = sk_attach_filter(&fprog, sk);
1000 		}
1001 		break;
1002 
1003 	case SO_ATTACH_BPF:
1004 		ret = -EINVAL;
1005 		if (optlen == sizeof(u32)) {
1006 			u32 ufd;
1007 
1008 			ret = -EFAULT;
1009 			if (copy_from_user(&ufd, optval, sizeof(ufd)))
1010 				break;
1011 
1012 			ret = sk_attach_bpf(ufd, sk);
1013 		}
1014 		break;
1015 
1016 	case SO_ATTACH_REUSEPORT_CBPF:
1017 		ret = -EINVAL;
1018 		if (optlen == sizeof(struct sock_fprog)) {
1019 			struct sock_fprog fprog;
1020 
1021 			ret = -EFAULT;
1022 			if (copy_from_user(&fprog, optval, sizeof(fprog)))
1023 				break;
1024 
1025 			ret = sk_reuseport_attach_filter(&fprog, sk);
1026 		}
1027 		break;
1028 
1029 	case SO_ATTACH_REUSEPORT_EBPF:
1030 		ret = -EINVAL;
1031 		if (optlen == sizeof(u32)) {
1032 			u32 ufd;
1033 
1034 			ret = -EFAULT;
1035 			if (copy_from_user(&ufd, optval, sizeof(ufd)))
1036 				break;
1037 
1038 			ret = sk_reuseport_attach_bpf(ufd, sk);
1039 		}
1040 		break;
1041 
1042 	case SO_DETACH_FILTER:
1043 		ret = sk_detach_filter(sk);
1044 		break;
1045 
1046 	case SO_LOCK_FILTER:
1047 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1048 			ret = -EPERM;
1049 		else
1050 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1051 		break;
1052 
1053 	case SO_PASSSEC:
1054 		if (valbool)
1055 			set_bit(SOCK_PASSSEC, &sock->flags);
1056 		else
1057 			clear_bit(SOCK_PASSSEC, &sock->flags);
1058 		break;
1059 	case SO_MARK:
1060 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1061 			ret = -EPERM;
1062 		} else if (val != sk->sk_mark) {
1063 			sk->sk_mark = val;
1064 			sk_dst_reset(sk);
1065 		}
1066 		break;
1067 
1068 	case SO_RXQ_OVFL:
1069 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1070 		break;
1071 
1072 	case SO_WIFI_STATUS:
1073 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1074 		break;
1075 
1076 	case SO_PEEK_OFF:
1077 		if (sock->ops->set_peek_off)
1078 			ret = sock->ops->set_peek_off(sk, val);
1079 		else
1080 			ret = -EOPNOTSUPP;
1081 		break;
1082 
1083 	case SO_NOFCS:
1084 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1085 		break;
1086 
1087 	case SO_SELECT_ERR_QUEUE:
1088 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1089 		break;
1090 
1091 #ifdef CONFIG_NET_RX_BUSY_POLL
1092 	case SO_BUSY_POLL:
1093 		/* allow unprivileged users to decrease the value */
1094 		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1095 			ret = -EPERM;
1096 		else {
1097 			if (val < 0)
1098 				ret = -EINVAL;
1099 			else
1100 				sk->sk_ll_usec = val;
1101 		}
1102 		break;
1103 #endif
1104 
1105 	case SO_MAX_PACING_RATE:
1106 		{
1107 		unsigned long ulval = (val == ~0U) ? ~0UL : val;
1108 
1109 		if (sizeof(ulval) != sizeof(val) &&
1110 		    optlen >= sizeof(ulval) &&
1111 		    get_user(ulval, (unsigned long __user *)optval)) {
1112 			ret = -EFAULT;
1113 			break;
1114 		}
1115 		if (ulval != ~0UL)
1116 			cmpxchg(&sk->sk_pacing_status,
1117 				SK_PACING_NONE,
1118 				SK_PACING_NEEDED);
1119 		sk->sk_max_pacing_rate = ulval;
1120 		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1121 		break;
1122 		}
1123 	case SO_INCOMING_CPU:
1124 		sk->sk_incoming_cpu = val;
1125 		break;
1126 
1127 	case SO_CNX_ADVICE:
1128 		if (val == 1)
1129 			dst_negative_advice(sk);
1130 		break;
1131 
1132 	case SO_ZEROCOPY:
1133 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1134 			if (!((sk->sk_type == SOCK_STREAM &&
1135 			       sk->sk_protocol == IPPROTO_TCP) ||
1136 			      (sk->sk_type == SOCK_DGRAM &&
1137 			       sk->sk_protocol == IPPROTO_UDP)))
1138 				ret = -ENOTSUPP;
1139 		} else if (sk->sk_family != PF_RDS) {
1140 			ret = -ENOTSUPP;
1141 		}
1142 		if (!ret) {
1143 			if (val < 0 || val > 1)
1144 				ret = -EINVAL;
1145 			else
1146 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1147 		}
1148 		break;
1149 
1150 	case SO_TXTIME:
1151 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1152 			ret = -EPERM;
1153 		} else if (optlen != sizeof(struct sock_txtime)) {
1154 			ret = -EINVAL;
1155 		} else if (copy_from_user(&sk_txtime, optval,
1156 			   sizeof(struct sock_txtime))) {
1157 			ret = -EFAULT;
1158 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1159 			ret = -EINVAL;
1160 		} else {
1161 			sock_valbool_flag(sk, SOCK_TXTIME, true);
1162 			sk->sk_clockid = sk_txtime.clockid;
1163 			sk->sk_txtime_deadline_mode =
1164 				!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1165 			sk->sk_txtime_report_errors =
1166 				!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1167 		}
1168 		break;
1169 
1170 	case SO_BINDTOIFINDEX:
1171 		ret = sock_setbindtodevice_locked(sk, val);
1172 		break;
1173 
1174 	default:
1175 		ret = -ENOPROTOOPT;
1176 		break;
1177 	}
1178 	release_sock(sk);
1179 	return ret;
1180 }
1181 EXPORT_SYMBOL(sock_setsockopt);
1182 
1183 
1184 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1185 			  struct ucred *ucred)
1186 {
1187 	ucred->pid = pid_vnr(pid);
1188 	ucred->uid = ucred->gid = -1;
1189 	if (cred) {
1190 		struct user_namespace *current_ns = current_user_ns();
1191 
1192 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1193 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1194 	}
1195 }
1196 
1197 static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1198 {
1199 	struct user_namespace *user_ns = current_user_ns();
1200 	int i;
1201 
1202 	for (i = 0; i < src->ngroups; i++)
1203 		if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1204 			return -EFAULT;
1205 
1206 	return 0;
1207 }
1208 
1209 int sock_getsockopt(struct socket *sock, int level, int optname,
1210 		    char __user *optval, int __user *optlen)
1211 {
1212 	struct sock *sk = sock->sk;
1213 
1214 	union {
1215 		int val;
1216 		u64 val64;
1217 		unsigned long ulval;
1218 		struct linger ling;
1219 		struct old_timeval32 tm32;
1220 		struct __kernel_old_timeval tm;
1221 		struct  __kernel_sock_timeval stm;
1222 		struct sock_txtime txtime;
1223 	} v;
1224 
1225 	int lv = sizeof(int);
1226 	int len;
1227 
1228 	if (get_user(len, optlen))
1229 		return -EFAULT;
1230 	if (len < 0)
1231 		return -EINVAL;
1232 
1233 	memset(&v, 0, sizeof(v));
1234 
1235 	switch (optname) {
1236 	case SO_DEBUG:
1237 		v.val = sock_flag(sk, SOCK_DBG);
1238 		break;
1239 
1240 	case SO_DONTROUTE:
1241 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1242 		break;
1243 
1244 	case SO_BROADCAST:
1245 		v.val = sock_flag(sk, SOCK_BROADCAST);
1246 		break;
1247 
1248 	case SO_SNDBUF:
1249 		v.val = sk->sk_sndbuf;
1250 		break;
1251 
1252 	case SO_RCVBUF:
1253 		v.val = sk->sk_rcvbuf;
1254 		break;
1255 
1256 	case SO_REUSEADDR:
1257 		v.val = sk->sk_reuse;
1258 		break;
1259 
1260 	case SO_REUSEPORT:
1261 		v.val = sk->sk_reuseport;
1262 		break;
1263 
1264 	case SO_KEEPALIVE:
1265 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1266 		break;
1267 
1268 	case SO_TYPE:
1269 		v.val = sk->sk_type;
1270 		break;
1271 
1272 	case SO_PROTOCOL:
1273 		v.val = sk->sk_protocol;
1274 		break;
1275 
1276 	case SO_DOMAIN:
1277 		v.val = sk->sk_family;
1278 		break;
1279 
1280 	case SO_ERROR:
1281 		v.val = -sock_error(sk);
1282 		if (v.val == 0)
1283 			v.val = xchg(&sk->sk_err_soft, 0);
1284 		break;
1285 
1286 	case SO_OOBINLINE:
1287 		v.val = sock_flag(sk, SOCK_URGINLINE);
1288 		break;
1289 
1290 	case SO_NO_CHECK:
1291 		v.val = sk->sk_no_check_tx;
1292 		break;
1293 
1294 	case SO_PRIORITY:
1295 		v.val = sk->sk_priority;
1296 		break;
1297 
1298 	case SO_LINGER:
1299 		lv		= sizeof(v.ling);
1300 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1301 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1302 		break;
1303 
1304 	case SO_BSDCOMPAT:
1305 		sock_warn_obsolete_bsdism("getsockopt");
1306 		break;
1307 
1308 	case SO_TIMESTAMP_OLD:
1309 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1310 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1311 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1312 		break;
1313 
1314 	case SO_TIMESTAMPNS_OLD:
1315 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1316 		break;
1317 
1318 	case SO_TIMESTAMP_NEW:
1319 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1320 		break;
1321 
1322 	case SO_TIMESTAMPNS_NEW:
1323 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1324 		break;
1325 
1326 	case SO_TIMESTAMPING_OLD:
1327 		v.val = sk->sk_tsflags;
1328 		break;
1329 
1330 	case SO_RCVTIMEO_OLD:
1331 	case SO_RCVTIMEO_NEW:
1332 		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1333 		break;
1334 
1335 	case SO_SNDTIMEO_OLD:
1336 	case SO_SNDTIMEO_NEW:
1337 		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1338 		break;
1339 
1340 	case SO_RCVLOWAT:
1341 		v.val = sk->sk_rcvlowat;
1342 		break;
1343 
1344 	case SO_SNDLOWAT:
1345 		v.val = 1;
1346 		break;
1347 
1348 	case SO_PASSCRED:
1349 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1350 		break;
1351 
1352 	case SO_PEERCRED:
1353 	{
1354 		struct ucred peercred;
1355 		if (len > sizeof(peercred))
1356 			len = sizeof(peercred);
1357 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1358 		if (copy_to_user(optval, &peercred, len))
1359 			return -EFAULT;
1360 		goto lenout;
1361 	}
1362 
1363 	case SO_PEERGROUPS:
1364 	{
1365 		int ret, n;
1366 
1367 		if (!sk->sk_peer_cred)
1368 			return -ENODATA;
1369 
1370 		n = sk->sk_peer_cred->group_info->ngroups;
1371 		if (len < n * sizeof(gid_t)) {
1372 			len = n * sizeof(gid_t);
1373 			return put_user(len, optlen) ? -EFAULT : -ERANGE;
1374 		}
1375 		len = n * sizeof(gid_t);
1376 
1377 		ret = groups_to_user((gid_t __user *)optval,
1378 				     sk->sk_peer_cred->group_info);
1379 		if (ret)
1380 			return ret;
1381 		goto lenout;
1382 	}
1383 
1384 	case SO_PEERNAME:
1385 	{
1386 		char address[128];
1387 
1388 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1389 		if (lv < 0)
1390 			return -ENOTCONN;
1391 		if (lv < len)
1392 			return -EINVAL;
1393 		if (copy_to_user(optval, address, len))
1394 			return -EFAULT;
1395 		goto lenout;
1396 	}
1397 
1398 	/* Dubious BSD thing... Probably nobody even uses it, but
1399 	 * the UNIX standard wants it for whatever reason... -DaveM
1400 	 */
1401 	case SO_ACCEPTCONN:
1402 		v.val = sk->sk_state == TCP_LISTEN;
1403 		break;
1404 
1405 	case SO_PASSSEC:
1406 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1407 		break;
1408 
1409 	case SO_PEERSEC:
1410 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1411 
1412 	case SO_MARK:
1413 		v.val = sk->sk_mark;
1414 		break;
1415 
1416 	case SO_RXQ_OVFL:
1417 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1418 		break;
1419 
1420 	case SO_WIFI_STATUS:
1421 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1422 		break;
1423 
1424 	case SO_PEEK_OFF:
1425 		if (!sock->ops->set_peek_off)
1426 			return -EOPNOTSUPP;
1427 
1428 		v.val = sk->sk_peek_off;
1429 		break;
1430 	case SO_NOFCS:
1431 		v.val = sock_flag(sk, SOCK_NOFCS);
1432 		break;
1433 
1434 	case SO_BINDTODEVICE:
1435 		return sock_getbindtodevice(sk, optval, optlen, len);
1436 
1437 	case SO_GET_FILTER:
1438 		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1439 		if (len < 0)
1440 			return len;
1441 
1442 		goto lenout;
1443 
1444 	case SO_LOCK_FILTER:
1445 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1446 		break;
1447 
1448 	case SO_BPF_EXTENSIONS:
1449 		v.val = bpf_tell_extensions();
1450 		break;
1451 
1452 	case SO_SELECT_ERR_QUEUE:
1453 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1454 		break;
1455 
1456 #ifdef CONFIG_NET_RX_BUSY_POLL
1457 	case SO_BUSY_POLL:
1458 		v.val = sk->sk_ll_usec;
1459 		break;
1460 #endif
1461 
1462 	case SO_MAX_PACING_RATE:
1463 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1464 			lv = sizeof(v.ulval);
1465 			v.ulval = sk->sk_max_pacing_rate;
1466 		} else {
1467 			/* 32bit version */
1468 			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1469 		}
1470 		break;
1471 
1472 	case SO_INCOMING_CPU:
1473 		v.val = sk->sk_incoming_cpu;
1474 		break;
1475 
1476 	case SO_MEMINFO:
1477 	{
1478 		u32 meminfo[SK_MEMINFO_VARS];
1479 
1480 		if (get_user(len, optlen))
1481 			return -EFAULT;
1482 
1483 		sk_get_meminfo(sk, meminfo);
1484 
1485 		len = min_t(unsigned int, len, sizeof(meminfo));
1486 		if (copy_to_user(optval, &meminfo, len))
1487 			return -EFAULT;
1488 
1489 		goto lenout;
1490 	}
1491 
1492 #ifdef CONFIG_NET_RX_BUSY_POLL
1493 	case SO_INCOMING_NAPI_ID:
1494 		v.val = READ_ONCE(sk->sk_napi_id);
1495 
1496 		/* aggregate non-NAPI IDs down to 0 */
1497 		if (v.val < MIN_NAPI_ID)
1498 			v.val = 0;
1499 
1500 		break;
1501 #endif
1502 
1503 	case SO_COOKIE:
1504 		lv = sizeof(u64);
1505 		if (len < lv)
1506 			return -EINVAL;
1507 		v.val64 = sock_gen_cookie(sk);
1508 		break;
1509 
1510 	case SO_ZEROCOPY:
1511 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1512 		break;
1513 
1514 	case SO_TXTIME:
1515 		lv = sizeof(v.txtime);
1516 		v.txtime.clockid = sk->sk_clockid;
1517 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1518 				  SOF_TXTIME_DEADLINE_MODE : 0;
1519 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1520 				  SOF_TXTIME_REPORT_ERRORS : 0;
1521 		break;
1522 
1523 	case SO_BINDTOIFINDEX:
1524 		v.val = sk->sk_bound_dev_if;
1525 		break;
1526 
1527 	default:
1528 		/* We implement the SO_SNDLOWAT etc to not be settable
1529 		 * (1003.1g 7).
1530 		 */
1531 		return -ENOPROTOOPT;
1532 	}
1533 
1534 	if (len > lv)
1535 		len = lv;
1536 	if (copy_to_user(optval, &v, len))
1537 		return -EFAULT;
1538 lenout:
1539 	if (put_user(len, optlen))
1540 		return -EFAULT;
1541 	return 0;
1542 }
1543 
1544 /*
1545  * Initialize an sk_lock.
1546  *
1547  * (We also register the sk_lock with the lock validator.)
1548  */
1549 static inline void sock_lock_init(struct sock *sk)
1550 {
1551 	if (sk->sk_kern_sock)
1552 		sock_lock_init_class_and_name(
1553 			sk,
1554 			af_family_kern_slock_key_strings[sk->sk_family],
1555 			af_family_kern_slock_keys + sk->sk_family,
1556 			af_family_kern_key_strings[sk->sk_family],
1557 			af_family_kern_keys + sk->sk_family);
1558 	else
1559 		sock_lock_init_class_and_name(
1560 			sk,
1561 			af_family_slock_key_strings[sk->sk_family],
1562 			af_family_slock_keys + sk->sk_family,
1563 			af_family_key_strings[sk->sk_family],
1564 			af_family_keys + sk->sk_family);
1565 }
1566 
1567 /*
1568  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1569  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1570  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1571  */
1572 static void sock_copy(struct sock *nsk, const struct sock *osk)
1573 {
1574 #ifdef CONFIG_SECURITY_NETWORK
1575 	void *sptr = nsk->sk_security;
1576 #endif
1577 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1578 
1579 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1580 	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1581 
1582 #ifdef CONFIG_SECURITY_NETWORK
1583 	nsk->sk_security = sptr;
1584 	security_sk_clone(osk, nsk);
1585 #endif
1586 }
1587 
1588 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1589 		int family)
1590 {
1591 	struct sock *sk;
1592 	struct kmem_cache *slab;
1593 
1594 	slab = prot->slab;
1595 	if (slab != NULL) {
1596 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1597 		if (!sk)
1598 			return sk;
1599 		if (priority & __GFP_ZERO)
1600 			sk_prot_clear_nulls(sk, prot->obj_size);
1601 	} else
1602 		sk = kmalloc(prot->obj_size, priority);
1603 
1604 	if (sk != NULL) {
1605 		if (security_sk_alloc(sk, family, priority))
1606 			goto out_free;
1607 
1608 		if (!try_module_get(prot->owner))
1609 			goto out_free_sec;
1610 		sk_tx_queue_clear(sk);
1611 	}
1612 
1613 	return sk;
1614 
1615 out_free_sec:
1616 	security_sk_free(sk);
1617 out_free:
1618 	if (slab != NULL)
1619 		kmem_cache_free(slab, sk);
1620 	else
1621 		kfree(sk);
1622 	return NULL;
1623 }
1624 
1625 static void sk_prot_free(struct proto *prot, struct sock *sk)
1626 {
1627 	struct kmem_cache *slab;
1628 	struct module *owner;
1629 
1630 	owner = prot->owner;
1631 	slab = prot->slab;
1632 
1633 	cgroup_sk_free(&sk->sk_cgrp_data);
1634 	mem_cgroup_sk_free(sk);
1635 	security_sk_free(sk);
1636 	if (slab != NULL)
1637 		kmem_cache_free(slab, sk);
1638 	else
1639 		kfree(sk);
1640 	module_put(owner);
1641 }
1642 
1643 /**
1644  *	sk_alloc - All socket objects are allocated here
1645  *	@net: the applicable net namespace
1646  *	@family: protocol family
1647  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1648  *	@prot: struct proto associated with this new sock instance
1649  *	@kern: is this to be a kernel socket?
1650  */
1651 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1652 		      struct proto *prot, int kern)
1653 {
1654 	struct sock *sk;
1655 
1656 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1657 	if (sk) {
1658 		sk->sk_family = family;
1659 		/*
1660 		 * See comment in struct sock definition to understand
1661 		 * why we need sk_prot_creator -acme
1662 		 */
1663 		sk->sk_prot = sk->sk_prot_creator = prot;
1664 		sk->sk_kern_sock = kern;
1665 		sock_lock_init(sk);
1666 		sk->sk_net_refcnt = kern ? 0 : 1;
1667 		if (likely(sk->sk_net_refcnt)) {
1668 			get_net(net);
1669 			sock_inuse_add(net, 1);
1670 		}
1671 
1672 		sock_net_set(sk, net);
1673 		refcount_set(&sk->sk_wmem_alloc, 1);
1674 
1675 		mem_cgroup_sk_alloc(sk);
1676 		cgroup_sk_alloc(&sk->sk_cgrp_data);
1677 		sock_update_classid(&sk->sk_cgrp_data);
1678 		sock_update_netprioidx(&sk->sk_cgrp_data);
1679 	}
1680 
1681 	return sk;
1682 }
1683 EXPORT_SYMBOL(sk_alloc);
1684 
1685 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
1686  * grace period. This is the case for UDP sockets and TCP listeners.
1687  */
1688 static void __sk_destruct(struct rcu_head *head)
1689 {
1690 	struct sock *sk = container_of(head, struct sock, sk_rcu);
1691 	struct sk_filter *filter;
1692 
1693 	if (sk->sk_destruct)
1694 		sk->sk_destruct(sk);
1695 
1696 	filter = rcu_dereference_check(sk->sk_filter,
1697 				       refcount_read(&sk->sk_wmem_alloc) == 0);
1698 	if (filter) {
1699 		sk_filter_uncharge(sk, filter);
1700 		RCU_INIT_POINTER(sk->sk_filter, NULL);
1701 	}
1702 	if (rcu_access_pointer(sk->sk_reuseport_cb))
1703 		reuseport_detach_sock(sk);
1704 
1705 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1706 
1707 #ifdef CONFIG_BPF_SYSCALL
1708 	bpf_sk_storage_free(sk);
1709 #endif
1710 
1711 	if (atomic_read(&sk->sk_omem_alloc))
1712 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1713 			 __func__, atomic_read(&sk->sk_omem_alloc));
1714 
1715 	if (sk->sk_frag.page) {
1716 		put_page(sk->sk_frag.page);
1717 		sk->sk_frag.page = NULL;
1718 	}
1719 
1720 	if (sk->sk_peer_cred)
1721 		put_cred(sk->sk_peer_cred);
1722 	put_pid(sk->sk_peer_pid);
1723 	if (likely(sk->sk_net_refcnt))
1724 		put_net(sock_net(sk));
1725 	sk_prot_free(sk->sk_prot_creator, sk);
1726 }
1727 
1728 void sk_destruct(struct sock *sk)
1729 {
1730 	if (sock_flag(sk, SOCK_RCU_FREE))
1731 		call_rcu(&sk->sk_rcu, __sk_destruct);
1732 	else
1733 		__sk_destruct(&sk->sk_rcu);
1734 }
1735 
1736 static void __sk_free(struct sock *sk)
1737 {
1738 	if (likely(sk->sk_net_refcnt))
1739 		sock_inuse_add(sock_net(sk), -1);
1740 
1741 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
1742 		sock_diag_broadcast_destroy(sk);
1743 	else
1744 		sk_destruct(sk);
1745 }
1746 
1747 void sk_free(struct sock *sk)
1748 {
1749 	/*
1750 	 * We subtract one from sk_wmem_alloc and can know if
1751 	 * some packets are still in some tx queue.
1752 	 * If not null, sock_wfree() will call __sk_free(sk) later
1753 	 */
1754 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
1755 		__sk_free(sk);
1756 }
1757 EXPORT_SYMBOL(sk_free);
1758 
1759 static void sk_init_common(struct sock *sk)
1760 {
1761 	skb_queue_head_init(&sk->sk_receive_queue);
1762 	skb_queue_head_init(&sk->sk_write_queue);
1763 	skb_queue_head_init(&sk->sk_error_queue);
1764 
1765 	rwlock_init(&sk->sk_callback_lock);
1766 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
1767 			af_rlock_keys + sk->sk_family,
1768 			af_family_rlock_key_strings[sk->sk_family]);
1769 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
1770 			af_wlock_keys + sk->sk_family,
1771 			af_family_wlock_key_strings[sk->sk_family]);
1772 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
1773 			af_elock_keys + sk->sk_family,
1774 			af_family_elock_key_strings[sk->sk_family]);
1775 	lockdep_set_class_and_name(&sk->sk_callback_lock,
1776 			af_callback_keys + sk->sk_family,
1777 			af_family_clock_key_strings[sk->sk_family]);
1778 }
1779 
1780 /**
1781  *	sk_clone_lock - clone a socket, and lock its clone
1782  *	@sk: the socket to clone
1783  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1784  *
1785  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1786  */
1787 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1788 {
1789 	struct sock *newsk;
1790 	bool is_charged = true;
1791 
1792 	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1793 	if (newsk != NULL) {
1794 		struct sk_filter *filter;
1795 
1796 		sock_copy(newsk, sk);
1797 
1798 		newsk->sk_prot_creator = sk->sk_prot;
1799 
1800 		/* SANITY */
1801 		if (likely(newsk->sk_net_refcnt))
1802 			get_net(sock_net(newsk));
1803 		sk_node_init(&newsk->sk_node);
1804 		sock_lock_init(newsk);
1805 		bh_lock_sock(newsk);
1806 		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1807 		newsk->sk_backlog.len = 0;
1808 
1809 		atomic_set(&newsk->sk_rmem_alloc, 0);
1810 		/*
1811 		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1812 		 */
1813 		refcount_set(&newsk->sk_wmem_alloc, 1);
1814 		atomic_set(&newsk->sk_omem_alloc, 0);
1815 		sk_init_common(newsk);
1816 
1817 		newsk->sk_dst_cache	= NULL;
1818 		newsk->sk_dst_pending_confirm = 0;
1819 		newsk->sk_wmem_queued	= 0;
1820 		newsk->sk_forward_alloc = 0;
1821 		atomic_set(&newsk->sk_drops, 0);
1822 		newsk->sk_send_head	= NULL;
1823 		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1824 		atomic_set(&newsk->sk_zckey, 0);
1825 
1826 		sock_reset_flag(newsk, SOCK_DONE);
1827 		mem_cgroup_sk_alloc(newsk);
1828 		cgroup_sk_alloc(&newsk->sk_cgrp_data);
1829 
1830 		rcu_read_lock();
1831 		filter = rcu_dereference(sk->sk_filter);
1832 		if (filter != NULL)
1833 			/* though it's an empty new sock, the charging may fail
1834 			 * if sysctl_optmem_max was changed between creation of
1835 			 * original socket and cloning
1836 			 */
1837 			is_charged = sk_filter_charge(newsk, filter);
1838 		RCU_INIT_POINTER(newsk->sk_filter, filter);
1839 		rcu_read_unlock();
1840 
1841 		if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1842 			/* We need to make sure that we don't uncharge the new
1843 			 * socket if we couldn't charge it in the first place
1844 			 * as otherwise we uncharge the parent's filter.
1845 			 */
1846 			if (!is_charged)
1847 				RCU_INIT_POINTER(newsk->sk_filter, NULL);
1848 			sk_free_unlock_clone(newsk);
1849 			newsk = NULL;
1850 			goto out;
1851 		}
1852 		RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1853 
1854 		newsk->sk_err	   = 0;
1855 		newsk->sk_err_soft = 0;
1856 		newsk->sk_priority = 0;
1857 		newsk->sk_incoming_cpu = raw_smp_processor_id();
1858 		if (likely(newsk->sk_net_refcnt))
1859 			sock_inuse_add(sock_net(newsk), 1);
1860 
1861 		/*
1862 		 * Before updating sk_refcnt, we must commit prior changes to memory
1863 		 * (Documentation/RCU/rculist_nulls.txt for details)
1864 		 */
1865 		smp_wmb();
1866 		refcount_set(&newsk->sk_refcnt, 2);
1867 
1868 		/*
1869 		 * Increment the counter in the same struct proto as the master
1870 		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1871 		 * is the same as sk->sk_prot->socks, as this field was copied
1872 		 * with memcpy).
1873 		 *
1874 		 * This _changes_ the previous behaviour, where
1875 		 * tcp_create_openreq_child always was incrementing the
1876 		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1877 		 * to be taken into account in all callers. -acme
1878 		 */
1879 		sk_refcnt_debug_inc(newsk);
1880 		sk_set_socket(newsk, NULL);
1881 		RCU_INIT_POINTER(newsk->sk_wq, NULL);
1882 
1883 		if (newsk->sk_prot->sockets_allocated)
1884 			sk_sockets_allocated_inc(newsk);
1885 
1886 		if (sock_needs_netstamp(sk) &&
1887 		    newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1888 			net_enable_timestamp();
1889 	}
1890 out:
1891 	return newsk;
1892 }
1893 EXPORT_SYMBOL_GPL(sk_clone_lock);
1894 
1895 void sk_free_unlock_clone(struct sock *sk)
1896 {
1897 	/* It is still raw copy of parent, so invalidate
1898 	 * destructor and make plain sk_free() */
1899 	sk->sk_destruct = NULL;
1900 	bh_unlock_sock(sk);
1901 	sk_free(sk);
1902 }
1903 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
1904 
1905 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1906 {
1907 	u32 max_segs = 1;
1908 
1909 	sk_dst_set(sk, dst);
1910 	sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps;
1911 	if (sk->sk_route_caps & NETIF_F_GSO)
1912 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1913 	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1914 	if (sk_can_gso(sk)) {
1915 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
1916 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1917 		} else {
1918 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1919 			sk->sk_gso_max_size = dst->dev->gso_max_size;
1920 			max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1921 		}
1922 	}
1923 	sk->sk_gso_max_segs = max_segs;
1924 }
1925 EXPORT_SYMBOL_GPL(sk_setup_caps);
1926 
1927 /*
1928  *	Simple resource managers for sockets.
1929  */
1930 
1931 
1932 /*
1933  * Write buffer destructor automatically called from kfree_skb.
1934  */
1935 void sock_wfree(struct sk_buff *skb)
1936 {
1937 	struct sock *sk = skb->sk;
1938 	unsigned int len = skb->truesize;
1939 
1940 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1941 		/*
1942 		 * Keep a reference on sk_wmem_alloc, this will be released
1943 		 * after sk_write_space() call
1944 		 */
1945 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
1946 		sk->sk_write_space(sk);
1947 		len = 1;
1948 	}
1949 	/*
1950 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1951 	 * could not do because of in-flight packets
1952 	 */
1953 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
1954 		__sk_free(sk);
1955 }
1956 EXPORT_SYMBOL(sock_wfree);
1957 
1958 /* This variant of sock_wfree() is used by TCP,
1959  * since it sets SOCK_USE_WRITE_QUEUE.
1960  */
1961 void __sock_wfree(struct sk_buff *skb)
1962 {
1963 	struct sock *sk = skb->sk;
1964 
1965 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
1966 		__sk_free(sk);
1967 }
1968 
1969 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1970 {
1971 	skb_orphan(skb);
1972 	skb->sk = sk;
1973 #ifdef CONFIG_INET
1974 	if (unlikely(!sk_fullsock(sk))) {
1975 		skb->destructor = sock_edemux;
1976 		sock_hold(sk);
1977 		return;
1978 	}
1979 #endif
1980 	skb->destructor = sock_wfree;
1981 	skb_set_hash_from_sk(skb, sk);
1982 	/*
1983 	 * We used to take a refcount on sk, but following operation
1984 	 * is enough to guarantee sk_free() wont free this sock until
1985 	 * all in-flight packets are completed
1986 	 */
1987 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
1988 }
1989 EXPORT_SYMBOL(skb_set_owner_w);
1990 
1991 /* This helper is used by netem, as it can hold packets in its
1992  * delay queue. We want to allow the owner socket to send more
1993  * packets, as if they were already TX completed by a typical driver.
1994  * But we also want to keep skb->sk set because some packet schedulers
1995  * rely on it (sch_fq for example).
1996  */
1997 void skb_orphan_partial(struct sk_buff *skb)
1998 {
1999 	if (skb_is_tcp_pure_ack(skb))
2000 		return;
2001 
2002 	if (skb->destructor == sock_wfree
2003 #ifdef CONFIG_INET
2004 	    || skb->destructor == tcp_wfree
2005 #endif
2006 		) {
2007 		struct sock *sk = skb->sk;
2008 
2009 		if (refcount_inc_not_zero(&sk->sk_refcnt)) {
2010 			WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc));
2011 			skb->destructor = sock_efree;
2012 		}
2013 	} else {
2014 		skb_orphan(skb);
2015 	}
2016 }
2017 EXPORT_SYMBOL(skb_orphan_partial);
2018 
2019 /*
2020  * Read buffer destructor automatically called from kfree_skb.
2021  */
2022 void sock_rfree(struct sk_buff *skb)
2023 {
2024 	struct sock *sk = skb->sk;
2025 	unsigned int len = skb->truesize;
2026 
2027 	atomic_sub(len, &sk->sk_rmem_alloc);
2028 	sk_mem_uncharge(sk, len);
2029 }
2030 EXPORT_SYMBOL(sock_rfree);
2031 
2032 /*
2033  * Buffer destructor for skbs that are not used directly in read or write
2034  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2035  */
2036 void sock_efree(struct sk_buff *skb)
2037 {
2038 	sock_put(skb->sk);
2039 }
2040 EXPORT_SYMBOL(sock_efree);
2041 
2042 kuid_t sock_i_uid(struct sock *sk)
2043 {
2044 	kuid_t uid;
2045 
2046 	read_lock_bh(&sk->sk_callback_lock);
2047 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2048 	read_unlock_bh(&sk->sk_callback_lock);
2049 	return uid;
2050 }
2051 EXPORT_SYMBOL(sock_i_uid);
2052 
2053 unsigned long sock_i_ino(struct sock *sk)
2054 {
2055 	unsigned long ino;
2056 
2057 	read_lock_bh(&sk->sk_callback_lock);
2058 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2059 	read_unlock_bh(&sk->sk_callback_lock);
2060 	return ino;
2061 }
2062 EXPORT_SYMBOL(sock_i_ino);
2063 
2064 /*
2065  * Allocate a skb from the socket's send buffer.
2066  */
2067 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2068 			     gfp_t priority)
2069 {
2070 	if (force || refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
2071 		struct sk_buff *skb = alloc_skb(size, priority);
2072 		if (skb) {
2073 			skb_set_owner_w(skb, sk);
2074 			return skb;
2075 		}
2076 	}
2077 	return NULL;
2078 }
2079 EXPORT_SYMBOL(sock_wmalloc);
2080 
2081 static void sock_ofree(struct sk_buff *skb)
2082 {
2083 	struct sock *sk = skb->sk;
2084 
2085 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2086 }
2087 
2088 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2089 			     gfp_t priority)
2090 {
2091 	struct sk_buff *skb;
2092 
2093 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2094 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2095 	    sysctl_optmem_max)
2096 		return NULL;
2097 
2098 	skb = alloc_skb(size, priority);
2099 	if (!skb)
2100 		return NULL;
2101 
2102 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2103 	skb->sk = sk;
2104 	skb->destructor = sock_ofree;
2105 	return skb;
2106 }
2107 
2108 /*
2109  * Allocate a memory block from the socket's option memory buffer.
2110  */
2111 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2112 {
2113 	if ((unsigned int)size <= sysctl_optmem_max &&
2114 	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
2115 		void *mem;
2116 		/* First do the add, to avoid the race if kmalloc
2117 		 * might sleep.
2118 		 */
2119 		atomic_add(size, &sk->sk_omem_alloc);
2120 		mem = kmalloc(size, priority);
2121 		if (mem)
2122 			return mem;
2123 		atomic_sub(size, &sk->sk_omem_alloc);
2124 	}
2125 	return NULL;
2126 }
2127 EXPORT_SYMBOL(sock_kmalloc);
2128 
2129 /* Free an option memory block. Note, we actually want the inline
2130  * here as this allows gcc to detect the nullify and fold away the
2131  * condition entirely.
2132  */
2133 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2134 				  const bool nullify)
2135 {
2136 	if (WARN_ON_ONCE(!mem))
2137 		return;
2138 	if (nullify)
2139 		kzfree(mem);
2140 	else
2141 		kfree(mem);
2142 	atomic_sub(size, &sk->sk_omem_alloc);
2143 }
2144 
2145 void sock_kfree_s(struct sock *sk, void *mem, int size)
2146 {
2147 	__sock_kfree_s(sk, mem, size, false);
2148 }
2149 EXPORT_SYMBOL(sock_kfree_s);
2150 
2151 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2152 {
2153 	__sock_kfree_s(sk, mem, size, true);
2154 }
2155 EXPORT_SYMBOL(sock_kzfree_s);
2156 
2157 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2158    I think, these locks should be removed for datagram sockets.
2159  */
2160 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2161 {
2162 	DEFINE_WAIT(wait);
2163 
2164 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2165 	for (;;) {
2166 		if (!timeo)
2167 			break;
2168 		if (signal_pending(current))
2169 			break;
2170 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2171 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2172 		if (refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
2173 			break;
2174 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2175 			break;
2176 		if (sk->sk_err)
2177 			break;
2178 		timeo = schedule_timeout(timeo);
2179 	}
2180 	finish_wait(sk_sleep(sk), &wait);
2181 	return timeo;
2182 }
2183 
2184 
2185 /*
2186  *	Generic send/receive buffer handlers
2187  */
2188 
2189 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2190 				     unsigned long data_len, int noblock,
2191 				     int *errcode, int max_page_order)
2192 {
2193 	struct sk_buff *skb;
2194 	long timeo;
2195 	int err;
2196 
2197 	timeo = sock_sndtimeo(sk, noblock);
2198 	for (;;) {
2199 		err = sock_error(sk);
2200 		if (err != 0)
2201 			goto failure;
2202 
2203 		err = -EPIPE;
2204 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2205 			goto failure;
2206 
2207 		if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
2208 			break;
2209 
2210 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2211 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2212 		err = -EAGAIN;
2213 		if (!timeo)
2214 			goto failure;
2215 		if (signal_pending(current))
2216 			goto interrupted;
2217 		timeo = sock_wait_for_wmem(sk, timeo);
2218 	}
2219 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2220 				   errcode, sk->sk_allocation);
2221 	if (skb)
2222 		skb_set_owner_w(skb, sk);
2223 	return skb;
2224 
2225 interrupted:
2226 	err = sock_intr_errno(timeo);
2227 failure:
2228 	*errcode = err;
2229 	return NULL;
2230 }
2231 EXPORT_SYMBOL(sock_alloc_send_pskb);
2232 
2233 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2234 				    int noblock, int *errcode)
2235 {
2236 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2237 }
2238 EXPORT_SYMBOL(sock_alloc_send_skb);
2239 
2240 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2241 		     struct sockcm_cookie *sockc)
2242 {
2243 	u32 tsflags;
2244 
2245 	switch (cmsg->cmsg_type) {
2246 	case SO_MARK:
2247 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2248 			return -EPERM;
2249 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2250 			return -EINVAL;
2251 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2252 		break;
2253 	case SO_TIMESTAMPING_OLD:
2254 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2255 			return -EINVAL;
2256 
2257 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2258 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2259 			return -EINVAL;
2260 
2261 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2262 		sockc->tsflags |= tsflags;
2263 		break;
2264 	case SCM_TXTIME:
2265 		if (!sock_flag(sk, SOCK_TXTIME))
2266 			return -EINVAL;
2267 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2268 			return -EINVAL;
2269 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2270 		break;
2271 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2272 	case SCM_RIGHTS:
2273 	case SCM_CREDENTIALS:
2274 		break;
2275 	default:
2276 		return -EINVAL;
2277 	}
2278 	return 0;
2279 }
2280 EXPORT_SYMBOL(__sock_cmsg_send);
2281 
2282 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2283 		   struct sockcm_cookie *sockc)
2284 {
2285 	struct cmsghdr *cmsg;
2286 	int ret;
2287 
2288 	for_each_cmsghdr(cmsg, msg) {
2289 		if (!CMSG_OK(msg, cmsg))
2290 			return -EINVAL;
2291 		if (cmsg->cmsg_level != SOL_SOCKET)
2292 			continue;
2293 		ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2294 		if (ret)
2295 			return ret;
2296 	}
2297 	return 0;
2298 }
2299 EXPORT_SYMBOL(sock_cmsg_send);
2300 
2301 static void sk_enter_memory_pressure(struct sock *sk)
2302 {
2303 	if (!sk->sk_prot->enter_memory_pressure)
2304 		return;
2305 
2306 	sk->sk_prot->enter_memory_pressure(sk);
2307 }
2308 
2309 static void sk_leave_memory_pressure(struct sock *sk)
2310 {
2311 	if (sk->sk_prot->leave_memory_pressure) {
2312 		sk->sk_prot->leave_memory_pressure(sk);
2313 	} else {
2314 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2315 
2316 		if (memory_pressure && *memory_pressure)
2317 			*memory_pressure = 0;
2318 	}
2319 }
2320 
2321 /* On 32bit arches, an skb frag is limited to 2^15 */
2322 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2323 
2324 /**
2325  * skb_page_frag_refill - check that a page_frag contains enough room
2326  * @sz: minimum size of the fragment we want to get
2327  * @pfrag: pointer to page_frag
2328  * @gfp: priority for memory allocation
2329  *
2330  * Note: While this allocator tries to use high order pages, there is
2331  * no guarantee that allocations succeed. Therefore, @sz MUST be
2332  * less or equal than PAGE_SIZE.
2333  */
2334 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2335 {
2336 	if (pfrag->page) {
2337 		if (page_ref_count(pfrag->page) == 1) {
2338 			pfrag->offset = 0;
2339 			return true;
2340 		}
2341 		if (pfrag->offset + sz <= pfrag->size)
2342 			return true;
2343 		put_page(pfrag->page);
2344 	}
2345 
2346 	pfrag->offset = 0;
2347 	if (SKB_FRAG_PAGE_ORDER) {
2348 		/* Avoid direct reclaim but allow kswapd to wake */
2349 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2350 					  __GFP_COMP | __GFP_NOWARN |
2351 					  __GFP_NORETRY,
2352 					  SKB_FRAG_PAGE_ORDER);
2353 		if (likely(pfrag->page)) {
2354 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2355 			return true;
2356 		}
2357 	}
2358 	pfrag->page = alloc_page(gfp);
2359 	if (likely(pfrag->page)) {
2360 		pfrag->size = PAGE_SIZE;
2361 		return true;
2362 	}
2363 	return false;
2364 }
2365 EXPORT_SYMBOL(skb_page_frag_refill);
2366 
2367 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2368 {
2369 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2370 		return true;
2371 
2372 	sk_enter_memory_pressure(sk);
2373 	sk_stream_moderate_sndbuf(sk);
2374 	return false;
2375 }
2376 EXPORT_SYMBOL(sk_page_frag_refill);
2377 
2378 static void __lock_sock(struct sock *sk)
2379 	__releases(&sk->sk_lock.slock)
2380 	__acquires(&sk->sk_lock.slock)
2381 {
2382 	DEFINE_WAIT(wait);
2383 
2384 	for (;;) {
2385 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2386 					TASK_UNINTERRUPTIBLE);
2387 		spin_unlock_bh(&sk->sk_lock.slock);
2388 		schedule();
2389 		spin_lock_bh(&sk->sk_lock.slock);
2390 		if (!sock_owned_by_user(sk))
2391 			break;
2392 	}
2393 	finish_wait(&sk->sk_lock.wq, &wait);
2394 }
2395 
2396 void __release_sock(struct sock *sk)
2397 	__releases(&sk->sk_lock.slock)
2398 	__acquires(&sk->sk_lock.slock)
2399 {
2400 	struct sk_buff *skb, *next;
2401 
2402 	while ((skb = sk->sk_backlog.head) != NULL) {
2403 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2404 
2405 		spin_unlock_bh(&sk->sk_lock.slock);
2406 
2407 		do {
2408 			next = skb->next;
2409 			prefetch(next);
2410 			WARN_ON_ONCE(skb_dst_is_noref(skb));
2411 			skb_mark_not_on_list(skb);
2412 			sk_backlog_rcv(sk, skb);
2413 
2414 			cond_resched();
2415 
2416 			skb = next;
2417 		} while (skb != NULL);
2418 
2419 		spin_lock_bh(&sk->sk_lock.slock);
2420 	}
2421 
2422 	/*
2423 	 * Doing the zeroing here guarantee we can not loop forever
2424 	 * while a wild producer attempts to flood us.
2425 	 */
2426 	sk->sk_backlog.len = 0;
2427 }
2428 
2429 void __sk_flush_backlog(struct sock *sk)
2430 {
2431 	spin_lock_bh(&sk->sk_lock.slock);
2432 	__release_sock(sk);
2433 	spin_unlock_bh(&sk->sk_lock.slock);
2434 }
2435 
2436 /**
2437  * sk_wait_data - wait for data to arrive at sk_receive_queue
2438  * @sk:    sock to wait on
2439  * @timeo: for how long
2440  * @skb:   last skb seen on sk_receive_queue
2441  *
2442  * Now socket state including sk->sk_err is changed only under lock,
2443  * hence we may omit checks after joining wait queue.
2444  * We check receive queue before schedule() only as optimization;
2445  * it is very likely that release_sock() added new data.
2446  */
2447 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2448 {
2449 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2450 	int rc;
2451 
2452 	add_wait_queue(sk_sleep(sk), &wait);
2453 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2454 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2455 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2456 	remove_wait_queue(sk_sleep(sk), &wait);
2457 	return rc;
2458 }
2459 EXPORT_SYMBOL(sk_wait_data);
2460 
2461 /**
2462  *	__sk_mem_raise_allocated - increase memory_allocated
2463  *	@sk: socket
2464  *	@size: memory size to allocate
2465  *	@amt: pages to allocate
2466  *	@kind: allocation type
2467  *
2468  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2469  */
2470 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2471 {
2472 	struct proto *prot = sk->sk_prot;
2473 	long allocated = sk_memory_allocated_add(sk, amt);
2474 	bool charged = true;
2475 
2476 	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2477 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt)))
2478 		goto suppress_allocation;
2479 
2480 	/* Under limit. */
2481 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2482 		sk_leave_memory_pressure(sk);
2483 		return 1;
2484 	}
2485 
2486 	/* Under pressure. */
2487 	if (allocated > sk_prot_mem_limits(sk, 1))
2488 		sk_enter_memory_pressure(sk);
2489 
2490 	/* Over hard limit. */
2491 	if (allocated > sk_prot_mem_limits(sk, 2))
2492 		goto suppress_allocation;
2493 
2494 	/* guarantee minimum buffer size under pressure */
2495 	if (kind == SK_MEM_RECV) {
2496 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2497 			return 1;
2498 
2499 	} else { /* SK_MEM_SEND */
2500 		int wmem0 = sk_get_wmem0(sk, prot);
2501 
2502 		if (sk->sk_type == SOCK_STREAM) {
2503 			if (sk->sk_wmem_queued < wmem0)
2504 				return 1;
2505 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
2506 				return 1;
2507 		}
2508 	}
2509 
2510 	if (sk_has_memory_pressure(sk)) {
2511 		u64 alloc;
2512 
2513 		if (!sk_under_memory_pressure(sk))
2514 			return 1;
2515 		alloc = sk_sockets_allocated_read_positive(sk);
2516 		if (sk_prot_mem_limits(sk, 2) > alloc *
2517 		    sk_mem_pages(sk->sk_wmem_queued +
2518 				 atomic_read(&sk->sk_rmem_alloc) +
2519 				 sk->sk_forward_alloc))
2520 			return 1;
2521 	}
2522 
2523 suppress_allocation:
2524 
2525 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2526 		sk_stream_moderate_sndbuf(sk);
2527 
2528 		/* Fail only if socket is _under_ its sndbuf.
2529 		 * In this case we cannot block, so that we have to fail.
2530 		 */
2531 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2532 			return 1;
2533 	}
2534 
2535 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
2536 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
2537 
2538 	sk_memory_allocated_sub(sk, amt);
2539 
2540 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2541 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2542 
2543 	return 0;
2544 }
2545 EXPORT_SYMBOL(__sk_mem_raise_allocated);
2546 
2547 /**
2548  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2549  *	@sk: socket
2550  *	@size: memory size to allocate
2551  *	@kind: allocation type
2552  *
2553  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2554  *	rmem allocation. This function assumes that protocols which have
2555  *	memory_pressure use sk_wmem_queued as write buffer accounting.
2556  */
2557 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2558 {
2559 	int ret, amt = sk_mem_pages(size);
2560 
2561 	sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2562 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2563 	if (!ret)
2564 		sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2565 	return ret;
2566 }
2567 EXPORT_SYMBOL(__sk_mem_schedule);
2568 
2569 /**
2570  *	__sk_mem_reduce_allocated - reclaim memory_allocated
2571  *	@sk: socket
2572  *	@amount: number of quanta
2573  *
2574  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2575  */
2576 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2577 {
2578 	sk_memory_allocated_sub(sk, amount);
2579 
2580 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2581 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2582 
2583 	if (sk_under_memory_pressure(sk) &&
2584 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2585 		sk_leave_memory_pressure(sk);
2586 }
2587 EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2588 
2589 /**
2590  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2591  *	@sk: socket
2592  *	@amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2593  */
2594 void __sk_mem_reclaim(struct sock *sk, int amount)
2595 {
2596 	amount >>= SK_MEM_QUANTUM_SHIFT;
2597 	sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2598 	__sk_mem_reduce_allocated(sk, amount);
2599 }
2600 EXPORT_SYMBOL(__sk_mem_reclaim);
2601 
2602 int sk_set_peek_off(struct sock *sk, int val)
2603 {
2604 	sk->sk_peek_off = val;
2605 	return 0;
2606 }
2607 EXPORT_SYMBOL_GPL(sk_set_peek_off);
2608 
2609 /*
2610  * Set of default routines for initialising struct proto_ops when
2611  * the protocol does not support a particular function. In certain
2612  * cases where it makes no sense for a protocol to have a "do nothing"
2613  * function, some default processing is provided.
2614  */
2615 
2616 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2617 {
2618 	return -EOPNOTSUPP;
2619 }
2620 EXPORT_SYMBOL(sock_no_bind);
2621 
2622 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2623 		    int len, int flags)
2624 {
2625 	return -EOPNOTSUPP;
2626 }
2627 EXPORT_SYMBOL(sock_no_connect);
2628 
2629 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2630 {
2631 	return -EOPNOTSUPP;
2632 }
2633 EXPORT_SYMBOL(sock_no_socketpair);
2634 
2635 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2636 		   bool kern)
2637 {
2638 	return -EOPNOTSUPP;
2639 }
2640 EXPORT_SYMBOL(sock_no_accept);
2641 
2642 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2643 		    int peer)
2644 {
2645 	return -EOPNOTSUPP;
2646 }
2647 EXPORT_SYMBOL(sock_no_getname);
2648 
2649 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2650 {
2651 	return -EOPNOTSUPP;
2652 }
2653 EXPORT_SYMBOL(sock_no_ioctl);
2654 
2655 int sock_no_listen(struct socket *sock, int backlog)
2656 {
2657 	return -EOPNOTSUPP;
2658 }
2659 EXPORT_SYMBOL(sock_no_listen);
2660 
2661 int sock_no_shutdown(struct socket *sock, int how)
2662 {
2663 	return -EOPNOTSUPP;
2664 }
2665 EXPORT_SYMBOL(sock_no_shutdown);
2666 
2667 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2668 		    char __user *optval, unsigned int optlen)
2669 {
2670 	return -EOPNOTSUPP;
2671 }
2672 EXPORT_SYMBOL(sock_no_setsockopt);
2673 
2674 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2675 		    char __user *optval, int __user *optlen)
2676 {
2677 	return -EOPNOTSUPP;
2678 }
2679 EXPORT_SYMBOL(sock_no_getsockopt);
2680 
2681 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2682 {
2683 	return -EOPNOTSUPP;
2684 }
2685 EXPORT_SYMBOL(sock_no_sendmsg);
2686 
2687 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
2688 {
2689 	return -EOPNOTSUPP;
2690 }
2691 EXPORT_SYMBOL(sock_no_sendmsg_locked);
2692 
2693 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2694 		    int flags)
2695 {
2696 	return -EOPNOTSUPP;
2697 }
2698 EXPORT_SYMBOL(sock_no_recvmsg);
2699 
2700 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2701 {
2702 	/* Mirror missing mmap method error code */
2703 	return -ENODEV;
2704 }
2705 EXPORT_SYMBOL(sock_no_mmap);
2706 
2707 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2708 {
2709 	ssize_t res;
2710 	struct msghdr msg = {.msg_flags = flags};
2711 	struct kvec iov;
2712 	char *kaddr = kmap(page);
2713 	iov.iov_base = kaddr + offset;
2714 	iov.iov_len = size;
2715 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2716 	kunmap(page);
2717 	return res;
2718 }
2719 EXPORT_SYMBOL(sock_no_sendpage);
2720 
2721 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
2722 				int offset, size_t size, int flags)
2723 {
2724 	ssize_t res;
2725 	struct msghdr msg = {.msg_flags = flags};
2726 	struct kvec iov;
2727 	char *kaddr = kmap(page);
2728 
2729 	iov.iov_base = kaddr + offset;
2730 	iov.iov_len = size;
2731 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
2732 	kunmap(page);
2733 	return res;
2734 }
2735 EXPORT_SYMBOL(sock_no_sendpage_locked);
2736 
2737 /*
2738  *	Default Socket Callbacks
2739  */
2740 
2741 static void sock_def_wakeup(struct sock *sk)
2742 {
2743 	struct socket_wq *wq;
2744 
2745 	rcu_read_lock();
2746 	wq = rcu_dereference(sk->sk_wq);
2747 	if (skwq_has_sleeper(wq))
2748 		wake_up_interruptible_all(&wq->wait);
2749 	rcu_read_unlock();
2750 }
2751 
2752 static void sock_def_error_report(struct sock *sk)
2753 {
2754 	struct socket_wq *wq;
2755 
2756 	rcu_read_lock();
2757 	wq = rcu_dereference(sk->sk_wq);
2758 	if (skwq_has_sleeper(wq))
2759 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
2760 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2761 	rcu_read_unlock();
2762 }
2763 
2764 static void sock_def_readable(struct sock *sk)
2765 {
2766 	struct socket_wq *wq;
2767 
2768 	rcu_read_lock();
2769 	wq = rcu_dereference(sk->sk_wq);
2770 	if (skwq_has_sleeper(wq))
2771 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
2772 						EPOLLRDNORM | EPOLLRDBAND);
2773 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2774 	rcu_read_unlock();
2775 }
2776 
2777 static void sock_def_write_space(struct sock *sk)
2778 {
2779 	struct socket_wq *wq;
2780 
2781 	rcu_read_lock();
2782 
2783 	/* Do not wake up a writer until he can make "significant"
2784 	 * progress.  --DaveM
2785 	 */
2786 	if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2787 		wq = rcu_dereference(sk->sk_wq);
2788 		if (skwq_has_sleeper(wq))
2789 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
2790 						EPOLLWRNORM | EPOLLWRBAND);
2791 
2792 		/* Should agree with poll, otherwise some programs break */
2793 		if (sock_writeable(sk))
2794 			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2795 	}
2796 
2797 	rcu_read_unlock();
2798 }
2799 
2800 static void sock_def_destruct(struct sock *sk)
2801 {
2802 }
2803 
2804 void sk_send_sigurg(struct sock *sk)
2805 {
2806 	if (sk->sk_socket && sk->sk_socket->file)
2807 		if (send_sigurg(&sk->sk_socket->file->f_owner))
2808 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2809 }
2810 EXPORT_SYMBOL(sk_send_sigurg);
2811 
2812 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2813 		    unsigned long expires)
2814 {
2815 	if (!mod_timer(timer, expires))
2816 		sock_hold(sk);
2817 }
2818 EXPORT_SYMBOL(sk_reset_timer);
2819 
2820 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2821 {
2822 	if (del_timer(timer))
2823 		__sock_put(sk);
2824 }
2825 EXPORT_SYMBOL(sk_stop_timer);
2826 
2827 void sock_init_data(struct socket *sock, struct sock *sk)
2828 {
2829 	sk_init_common(sk);
2830 	sk->sk_send_head	=	NULL;
2831 
2832 	timer_setup(&sk->sk_timer, NULL, 0);
2833 
2834 	sk->sk_allocation	=	GFP_KERNEL;
2835 	sk->sk_rcvbuf		=	sysctl_rmem_default;
2836 	sk->sk_sndbuf		=	sysctl_wmem_default;
2837 	sk->sk_state		=	TCP_CLOSE;
2838 	sk_set_socket(sk, sock);
2839 
2840 	sock_set_flag(sk, SOCK_ZAPPED);
2841 
2842 	if (sock) {
2843 		sk->sk_type	=	sock->type;
2844 		RCU_INIT_POINTER(sk->sk_wq, sock->wq);
2845 		sock->sk	=	sk;
2846 		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
2847 	} else {
2848 		RCU_INIT_POINTER(sk->sk_wq, NULL);
2849 		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
2850 	}
2851 
2852 	rwlock_init(&sk->sk_callback_lock);
2853 	if (sk->sk_kern_sock)
2854 		lockdep_set_class_and_name(
2855 			&sk->sk_callback_lock,
2856 			af_kern_callback_keys + sk->sk_family,
2857 			af_family_kern_clock_key_strings[sk->sk_family]);
2858 	else
2859 		lockdep_set_class_and_name(
2860 			&sk->sk_callback_lock,
2861 			af_callback_keys + sk->sk_family,
2862 			af_family_clock_key_strings[sk->sk_family]);
2863 
2864 	sk->sk_state_change	=	sock_def_wakeup;
2865 	sk->sk_data_ready	=	sock_def_readable;
2866 	sk->sk_write_space	=	sock_def_write_space;
2867 	sk->sk_error_report	=	sock_def_error_report;
2868 	sk->sk_destruct		=	sock_def_destruct;
2869 
2870 	sk->sk_frag.page	=	NULL;
2871 	sk->sk_frag.offset	=	0;
2872 	sk->sk_peek_off		=	-1;
2873 
2874 	sk->sk_peer_pid 	=	NULL;
2875 	sk->sk_peer_cred	=	NULL;
2876 	sk->sk_write_pending	=	0;
2877 	sk->sk_rcvlowat		=	1;
2878 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2879 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2880 
2881 	sk->sk_stamp = SK_DEFAULT_STAMP;
2882 #if BITS_PER_LONG==32
2883 	seqlock_init(&sk->sk_stamp_seq);
2884 #endif
2885 	atomic_set(&sk->sk_zckey, 0);
2886 
2887 #ifdef CONFIG_NET_RX_BUSY_POLL
2888 	sk->sk_napi_id		=	0;
2889 	sk->sk_ll_usec		=	sysctl_net_busy_read;
2890 #endif
2891 
2892 	sk->sk_max_pacing_rate = ~0UL;
2893 	sk->sk_pacing_rate = ~0UL;
2894 	sk->sk_pacing_shift = 10;
2895 	sk->sk_incoming_cpu = -1;
2896 
2897 	sk_rx_queue_clear(sk);
2898 	/*
2899 	 * Before updating sk_refcnt, we must commit prior changes to memory
2900 	 * (Documentation/RCU/rculist_nulls.txt for details)
2901 	 */
2902 	smp_wmb();
2903 	refcount_set(&sk->sk_refcnt, 1);
2904 	atomic_set(&sk->sk_drops, 0);
2905 }
2906 EXPORT_SYMBOL(sock_init_data);
2907 
2908 void lock_sock_nested(struct sock *sk, int subclass)
2909 {
2910 	might_sleep();
2911 	spin_lock_bh(&sk->sk_lock.slock);
2912 	if (sk->sk_lock.owned)
2913 		__lock_sock(sk);
2914 	sk->sk_lock.owned = 1;
2915 	spin_unlock(&sk->sk_lock.slock);
2916 	/*
2917 	 * The sk_lock has mutex_lock() semantics here:
2918 	 */
2919 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2920 	local_bh_enable();
2921 }
2922 EXPORT_SYMBOL(lock_sock_nested);
2923 
2924 void release_sock(struct sock *sk)
2925 {
2926 	spin_lock_bh(&sk->sk_lock.slock);
2927 	if (sk->sk_backlog.tail)
2928 		__release_sock(sk);
2929 
2930 	/* Warning : release_cb() might need to release sk ownership,
2931 	 * ie call sock_release_ownership(sk) before us.
2932 	 */
2933 	if (sk->sk_prot->release_cb)
2934 		sk->sk_prot->release_cb(sk);
2935 
2936 	sock_release_ownership(sk);
2937 	if (waitqueue_active(&sk->sk_lock.wq))
2938 		wake_up(&sk->sk_lock.wq);
2939 	spin_unlock_bh(&sk->sk_lock.slock);
2940 }
2941 EXPORT_SYMBOL(release_sock);
2942 
2943 /**
2944  * lock_sock_fast - fast version of lock_sock
2945  * @sk: socket
2946  *
2947  * This version should be used for very small section, where process wont block
2948  * return false if fast path is taken:
2949  *
2950  *   sk_lock.slock locked, owned = 0, BH disabled
2951  *
2952  * return true if slow path is taken:
2953  *
2954  *   sk_lock.slock unlocked, owned = 1, BH enabled
2955  */
2956 bool lock_sock_fast(struct sock *sk)
2957 {
2958 	might_sleep();
2959 	spin_lock_bh(&sk->sk_lock.slock);
2960 
2961 	if (!sk->sk_lock.owned)
2962 		/*
2963 		 * Note : We must disable BH
2964 		 */
2965 		return false;
2966 
2967 	__lock_sock(sk);
2968 	sk->sk_lock.owned = 1;
2969 	spin_unlock(&sk->sk_lock.slock);
2970 	/*
2971 	 * The sk_lock has mutex_lock() semantics here:
2972 	 */
2973 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2974 	local_bh_enable();
2975 	return true;
2976 }
2977 EXPORT_SYMBOL(lock_sock_fast);
2978 
2979 int sock_gettstamp(struct socket *sock, void __user *userstamp,
2980 		   bool timeval, bool time32)
2981 {
2982 	struct sock *sk = sock->sk;
2983 	struct timespec64 ts;
2984 
2985 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2986 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
2987 	if (ts.tv_sec == -1)
2988 		return -ENOENT;
2989 	if (ts.tv_sec == 0) {
2990 		ktime_t kt = ktime_get_real();
2991 		sock_write_timestamp(sk, kt);;
2992 		ts = ktime_to_timespec64(kt);
2993 	}
2994 
2995 	if (timeval)
2996 		ts.tv_nsec /= 1000;
2997 
2998 #ifdef CONFIG_COMPAT_32BIT_TIME
2999 	if (time32)
3000 		return put_old_timespec32(&ts, userstamp);
3001 #endif
3002 #ifdef CONFIG_SPARC64
3003 	/* beware of padding in sparc64 timeval */
3004 	if (timeval && !in_compat_syscall()) {
3005 		struct __kernel_old_timeval __user tv = {
3006 			.tv_sec = ts.tv_sec,
3007 			.tv_usec = ts.tv_nsec,
3008 		};
3009 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3010 			return -EFAULT;
3011 		return 0;
3012 	}
3013 #endif
3014 	return put_timespec64(&ts, userstamp);
3015 }
3016 EXPORT_SYMBOL(sock_gettstamp);
3017 
3018 void sock_enable_timestamp(struct sock *sk, int flag)
3019 {
3020 	if (!sock_flag(sk, flag)) {
3021 		unsigned long previous_flags = sk->sk_flags;
3022 
3023 		sock_set_flag(sk, flag);
3024 		/*
3025 		 * we just set one of the two flags which require net
3026 		 * time stamping, but time stamping might have been on
3027 		 * already because of the other one
3028 		 */
3029 		if (sock_needs_netstamp(sk) &&
3030 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3031 			net_enable_timestamp();
3032 	}
3033 }
3034 
3035 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3036 		       int level, int type)
3037 {
3038 	struct sock_exterr_skb *serr;
3039 	struct sk_buff *skb;
3040 	int copied, err;
3041 
3042 	err = -EAGAIN;
3043 	skb = sock_dequeue_err_skb(sk);
3044 	if (skb == NULL)
3045 		goto out;
3046 
3047 	copied = skb->len;
3048 	if (copied > len) {
3049 		msg->msg_flags |= MSG_TRUNC;
3050 		copied = len;
3051 	}
3052 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3053 	if (err)
3054 		goto out_free_skb;
3055 
3056 	sock_recv_timestamp(msg, sk, skb);
3057 
3058 	serr = SKB_EXT_ERR(skb);
3059 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3060 
3061 	msg->msg_flags |= MSG_ERRQUEUE;
3062 	err = copied;
3063 
3064 out_free_skb:
3065 	kfree_skb(skb);
3066 out:
3067 	return err;
3068 }
3069 EXPORT_SYMBOL(sock_recv_errqueue);
3070 
3071 /*
3072  *	Get a socket option on an socket.
3073  *
3074  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3075  *	asynchronous errors should be reported by getsockopt. We assume
3076  *	this means if you specify SO_ERROR (otherwise whats the point of it).
3077  */
3078 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3079 			   char __user *optval, int __user *optlen)
3080 {
3081 	struct sock *sk = sock->sk;
3082 
3083 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3084 }
3085 EXPORT_SYMBOL(sock_common_getsockopt);
3086 
3087 #ifdef CONFIG_COMPAT
3088 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
3089 				  char __user *optval, int __user *optlen)
3090 {
3091 	struct sock *sk = sock->sk;
3092 
3093 	if (sk->sk_prot->compat_getsockopt != NULL)
3094 		return sk->sk_prot->compat_getsockopt(sk, level, optname,
3095 						      optval, optlen);
3096 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3097 }
3098 EXPORT_SYMBOL(compat_sock_common_getsockopt);
3099 #endif
3100 
3101 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3102 			int flags)
3103 {
3104 	struct sock *sk = sock->sk;
3105 	int addr_len = 0;
3106 	int err;
3107 
3108 	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
3109 				   flags & ~MSG_DONTWAIT, &addr_len);
3110 	if (err >= 0)
3111 		msg->msg_namelen = addr_len;
3112 	return err;
3113 }
3114 EXPORT_SYMBOL(sock_common_recvmsg);
3115 
3116 /*
3117  *	Set socket options on an inet socket.
3118  */
3119 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3120 			   char __user *optval, unsigned int optlen)
3121 {
3122 	struct sock *sk = sock->sk;
3123 
3124 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3125 }
3126 EXPORT_SYMBOL(sock_common_setsockopt);
3127 
3128 #ifdef CONFIG_COMPAT
3129 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
3130 				  char __user *optval, unsigned int optlen)
3131 {
3132 	struct sock *sk = sock->sk;
3133 
3134 	if (sk->sk_prot->compat_setsockopt != NULL)
3135 		return sk->sk_prot->compat_setsockopt(sk, level, optname,
3136 						      optval, optlen);
3137 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3138 }
3139 EXPORT_SYMBOL(compat_sock_common_setsockopt);
3140 #endif
3141 
3142 void sk_common_release(struct sock *sk)
3143 {
3144 	if (sk->sk_prot->destroy)
3145 		sk->sk_prot->destroy(sk);
3146 
3147 	/*
3148 	 * Observation: when sock_common_release is called, processes have
3149 	 * no access to socket. But net still has.
3150 	 * Step one, detach it from networking:
3151 	 *
3152 	 * A. Remove from hash tables.
3153 	 */
3154 
3155 	sk->sk_prot->unhash(sk);
3156 
3157 	/*
3158 	 * In this point socket cannot receive new packets, but it is possible
3159 	 * that some packets are in flight because some CPU runs receiver and
3160 	 * did hash table lookup before we unhashed socket. They will achieve
3161 	 * receive queue and will be purged by socket destructor.
3162 	 *
3163 	 * Also we still have packets pending on receive queue and probably,
3164 	 * our own packets waiting in device queues. sock_destroy will drain
3165 	 * receive queue, but transmitted packets will delay socket destruction
3166 	 * until the last reference will be released.
3167 	 */
3168 
3169 	sock_orphan(sk);
3170 
3171 	xfrm_sk_free_policy(sk);
3172 
3173 	sk_refcnt_debug_release(sk);
3174 
3175 	sock_put(sk);
3176 }
3177 EXPORT_SYMBOL(sk_common_release);
3178 
3179 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3180 {
3181 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3182 
3183 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3184 	mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
3185 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3186 	mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
3187 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3188 	mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
3189 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3190 	mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len;
3191 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3192 }
3193 
3194 #ifdef CONFIG_PROC_FS
3195 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
3196 struct prot_inuse {
3197 	int val[PROTO_INUSE_NR];
3198 };
3199 
3200 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3201 
3202 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3203 {
3204 	__this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
3205 }
3206 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3207 
3208 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3209 {
3210 	int cpu, idx = prot->inuse_idx;
3211 	int res = 0;
3212 
3213 	for_each_possible_cpu(cpu)
3214 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3215 
3216 	return res >= 0 ? res : 0;
3217 }
3218 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3219 
3220 static void sock_inuse_add(struct net *net, int val)
3221 {
3222 	this_cpu_add(*net->core.sock_inuse, val);
3223 }
3224 
3225 int sock_inuse_get(struct net *net)
3226 {
3227 	int cpu, res = 0;
3228 
3229 	for_each_possible_cpu(cpu)
3230 		res += *per_cpu_ptr(net->core.sock_inuse, cpu);
3231 
3232 	return res;
3233 }
3234 
3235 EXPORT_SYMBOL_GPL(sock_inuse_get);
3236 
3237 static int __net_init sock_inuse_init_net(struct net *net)
3238 {
3239 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3240 	if (net->core.prot_inuse == NULL)
3241 		return -ENOMEM;
3242 
3243 	net->core.sock_inuse = alloc_percpu(int);
3244 	if (net->core.sock_inuse == NULL)
3245 		goto out;
3246 
3247 	return 0;
3248 
3249 out:
3250 	free_percpu(net->core.prot_inuse);
3251 	return -ENOMEM;
3252 }
3253 
3254 static void __net_exit sock_inuse_exit_net(struct net *net)
3255 {
3256 	free_percpu(net->core.prot_inuse);
3257 	free_percpu(net->core.sock_inuse);
3258 }
3259 
3260 static struct pernet_operations net_inuse_ops = {
3261 	.init = sock_inuse_init_net,
3262 	.exit = sock_inuse_exit_net,
3263 };
3264 
3265 static __init int net_inuse_init(void)
3266 {
3267 	if (register_pernet_subsys(&net_inuse_ops))
3268 		panic("Cannot initialize net inuse counters");
3269 
3270 	return 0;
3271 }
3272 
3273 core_initcall(net_inuse_init);
3274 
3275 static void assign_proto_idx(struct proto *prot)
3276 {
3277 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3278 
3279 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3280 		pr_err("PROTO_INUSE_NR exhausted\n");
3281 		return;
3282 	}
3283 
3284 	set_bit(prot->inuse_idx, proto_inuse_idx);
3285 }
3286 
3287 static void release_proto_idx(struct proto *prot)
3288 {
3289 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3290 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3291 }
3292 #else
3293 static inline void assign_proto_idx(struct proto *prot)
3294 {
3295 }
3296 
3297 static inline void release_proto_idx(struct proto *prot)
3298 {
3299 }
3300 
3301 static void sock_inuse_add(struct net *net, int val)
3302 {
3303 }
3304 #endif
3305 
3306 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3307 {
3308 	if (!rsk_prot)
3309 		return;
3310 	kfree(rsk_prot->slab_name);
3311 	rsk_prot->slab_name = NULL;
3312 	kmem_cache_destroy(rsk_prot->slab);
3313 	rsk_prot->slab = NULL;
3314 }
3315 
3316 static int req_prot_init(const struct proto *prot)
3317 {
3318 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3319 
3320 	if (!rsk_prot)
3321 		return 0;
3322 
3323 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3324 					prot->name);
3325 	if (!rsk_prot->slab_name)
3326 		return -ENOMEM;
3327 
3328 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3329 					   rsk_prot->obj_size, 0,
3330 					   SLAB_ACCOUNT | prot->slab_flags,
3331 					   NULL);
3332 
3333 	if (!rsk_prot->slab) {
3334 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3335 			prot->name);
3336 		return -ENOMEM;
3337 	}
3338 	return 0;
3339 }
3340 
3341 int proto_register(struct proto *prot, int alloc_slab)
3342 {
3343 	if (alloc_slab) {
3344 		prot->slab = kmem_cache_create_usercopy(prot->name,
3345 					prot->obj_size, 0,
3346 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3347 					prot->slab_flags,
3348 					prot->useroffset, prot->usersize,
3349 					NULL);
3350 
3351 		if (prot->slab == NULL) {
3352 			pr_crit("%s: Can't create sock SLAB cache!\n",
3353 				prot->name);
3354 			goto out;
3355 		}
3356 
3357 		if (req_prot_init(prot))
3358 			goto out_free_request_sock_slab;
3359 
3360 		if (prot->twsk_prot != NULL) {
3361 			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
3362 
3363 			if (prot->twsk_prot->twsk_slab_name == NULL)
3364 				goto out_free_request_sock_slab;
3365 
3366 			prot->twsk_prot->twsk_slab =
3367 				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
3368 						  prot->twsk_prot->twsk_obj_size,
3369 						  0,
3370 						  SLAB_ACCOUNT |
3371 						  prot->slab_flags,
3372 						  NULL);
3373 			if (prot->twsk_prot->twsk_slab == NULL)
3374 				goto out_free_timewait_sock_slab_name;
3375 		}
3376 	}
3377 
3378 	mutex_lock(&proto_list_mutex);
3379 	list_add(&prot->node, &proto_list);
3380 	assign_proto_idx(prot);
3381 	mutex_unlock(&proto_list_mutex);
3382 	return 0;
3383 
3384 out_free_timewait_sock_slab_name:
3385 	kfree(prot->twsk_prot->twsk_slab_name);
3386 out_free_request_sock_slab:
3387 	req_prot_cleanup(prot->rsk_prot);
3388 
3389 	kmem_cache_destroy(prot->slab);
3390 	prot->slab = NULL;
3391 out:
3392 	return -ENOBUFS;
3393 }
3394 EXPORT_SYMBOL(proto_register);
3395 
3396 void proto_unregister(struct proto *prot)
3397 {
3398 	mutex_lock(&proto_list_mutex);
3399 	release_proto_idx(prot);
3400 	list_del(&prot->node);
3401 	mutex_unlock(&proto_list_mutex);
3402 
3403 	kmem_cache_destroy(prot->slab);
3404 	prot->slab = NULL;
3405 
3406 	req_prot_cleanup(prot->rsk_prot);
3407 
3408 	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
3409 		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
3410 		kfree(prot->twsk_prot->twsk_slab_name);
3411 		prot->twsk_prot->twsk_slab = NULL;
3412 	}
3413 }
3414 EXPORT_SYMBOL(proto_unregister);
3415 
3416 int sock_load_diag_module(int family, int protocol)
3417 {
3418 	if (!protocol) {
3419 		if (!sock_is_registered(family))
3420 			return -ENOENT;
3421 
3422 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3423 				      NETLINK_SOCK_DIAG, family);
3424 	}
3425 
3426 #ifdef CONFIG_INET
3427 	if (family == AF_INET &&
3428 	    protocol != IPPROTO_RAW &&
3429 	    !rcu_access_pointer(inet_protos[protocol]))
3430 		return -ENOENT;
3431 #endif
3432 
3433 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3434 			      NETLINK_SOCK_DIAG, family, protocol);
3435 }
3436 EXPORT_SYMBOL(sock_load_diag_module);
3437 
3438 #ifdef CONFIG_PROC_FS
3439 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3440 	__acquires(proto_list_mutex)
3441 {
3442 	mutex_lock(&proto_list_mutex);
3443 	return seq_list_start_head(&proto_list, *pos);
3444 }
3445 
3446 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3447 {
3448 	return seq_list_next(v, &proto_list, pos);
3449 }
3450 
3451 static void proto_seq_stop(struct seq_file *seq, void *v)
3452 	__releases(proto_list_mutex)
3453 {
3454 	mutex_unlock(&proto_list_mutex);
3455 }
3456 
3457 static char proto_method_implemented(const void *method)
3458 {
3459 	return method == NULL ? 'n' : 'y';
3460 }
3461 static long sock_prot_memory_allocated(struct proto *proto)
3462 {
3463 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3464 }
3465 
3466 static char *sock_prot_memory_pressure(struct proto *proto)
3467 {
3468 	return proto->memory_pressure != NULL ?
3469 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3470 }
3471 
3472 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3473 {
3474 
3475 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
3476 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3477 		   proto->name,
3478 		   proto->obj_size,
3479 		   sock_prot_inuse_get(seq_file_net(seq), proto),
3480 		   sock_prot_memory_allocated(proto),
3481 		   sock_prot_memory_pressure(proto),
3482 		   proto->max_header,
3483 		   proto->slab == NULL ? "no" : "yes",
3484 		   module_name(proto->owner),
3485 		   proto_method_implemented(proto->close),
3486 		   proto_method_implemented(proto->connect),
3487 		   proto_method_implemented(proto->disconnect),
3488 		   proto_method_implemented(proto->accept),
3489 		   proto_method_implemented(proto->ioctl),
3490 		   proto_method_implemented(proto->init),
3491 		   proto_method_implemented(proto->destroy),
3492 		   proto_method_implemented(proto->shutdown),
3493 		   proto_method_implemented(proto->setsockopt),
3494 		   proto_method_implemented(proto->getsockopt),
3495 		   proto_method_implemented(proto->sendmsg),
3496 		   proto_method_implemented(proto->recvmsg),
3497 		   proto_method_implemented(proto->sendpage),
3498 		   proto_method_implemented(proto->bind),
3499 		   proto_method_implemented(proto->backlog_rcv),
3500 		   proto_method_implemented(proto->hash),
3501 		   proto_method_implemented(proto->unhash),
3502 		   proto_method_implemented(proto->get_port),
3503 		   proto_method_implemented(proto->enter_memory_pressure));
3504 }
3505 
3506 static int proto_seq_show(struct seq_file *seq, void *v)
3507 {
3508 	if (v == &proto_list)
3509 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3510 			   "protocol",
3511 			   "size",
3512 			   "sockets",
3513 			   "memory",
3514 			   "press",
3515 			   "maxhdr",
3516 			   "slab",
3517 			   "module",
3518 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3519 	else
3520 		proto_seq_printf(seq, list_entry(v, struct proto, node));
3521 	return 0;
3522 }
3523 
3524 static const struct seq_operations proto_seq_ops = {
3525 	.start  = proto_seq_start,
3526 	.next   = proto_seq_next,
3527 	.stop   = proto_seq_stop,
3528 	.show   = proto_seq_show,
3529 };
3530 
3531 static __net_init int proto_init_net(struct net *net)
3532 {
3533 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
3534 			sizeof(struct seq_net_private)))
3535 		return -ENOMEM;
3536 
3537 	return 0;
3538 }
3539 
3540 static __net_exit void proto_exit_net(struct net *net)
3541 {
3542 	remove_proc_entry("protocols", net->proc_net);
3543 }
3544 
3545 
3546 static __net_initdata struct pernet_operations proto_net_ops = {
3547 	.init = proto_init_net,
3548 	.exit = proto_exit_net,
3549 };
3550 
3551 static int __init proto_init(void)
3552 {
3553 	return register_pernet_subsys(&proto_net_ops);
3554 }
3555 
3556 subsys_initcall(proto_init);
3557 
3558 #endif /* PROC_FS */
3559 
3560 #ifdef CONFIG_NET_RX_BUSY_POLL
3561 bool sk_busy_loop_end(void *p, unsigned long start_time)
3562 {
3563 	struct sock *sk = p;
3564 
3565 	return !skb_queue_empty(&sk->sk_receive_queue) ||
3566 	       sk_busy_loop_timeout(sk, start_time);
3567 }
3568 EXPORT_SYMBOL(sk_busy_loop_end);
3569 #endif /* CONFIG_NET_RX_BUSY_POLL */
3570