xref: /openbmc/linux/net/core/sock.c (revision cfba5de9)
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_REUSEPORT_BPF:
1043 		ret = reuseport_detach_prog(sk);
1044 		break;
1045 
1046 	case SO_DETACH_FILTER:
1047 		ret = sk_detach_filter(sk);
1048 		break;
1049 
1050 	case SO_LOCK_FILTER:
1051 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1052 			ret = -EPERM;
1053 		else
1054 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1055 		break;
1056 
1057 	case SO_PASSSEC:
1058 		if (valbool)
1059 			set_bit(SOCK_PASSSEC, &sock->flags);
1060 		else
1061 			clear_bit(SOCK_PASSSEC, &sock->flags);
1062 		break;
1063 	case SO_MARK:
1064 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1065 			ret = -EPERM;
1066 		} else if (val != sk->sk_mark) {
1067 			sk->sk_mark = val;
1068 			sk_dst_reset(sk);
1069 		}
1070 		break;
1071 
1072 	case SO_RXQ_OVFL:
1073 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1074 		break;
1075 
1076 	case SO_WIFI_STATUS:
1077 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1078 		break;
1079 
1080 	case SO_PEEK_OFF:
1081 		if (sock->ops->set_peek_off)
1082 			ret = sock->ops->set_peek_off(sk, val);
1083 		else
1084 			ret = -EOPNOTSUPP;
1085 		break;
1086 
1087 	case SO_NOFCS:
1088 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1089 		break;
1090 
1091 	case SO_SELECT_ERR_QUEUE:
1092 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1093 		break;
1094 
1095 #ifdef CONFIG_NET_RX_BUSY_POLL
1096 	case SO_BUSY_POLL:
1097 		/* allow unprivileged users to decrease the value */
1098 		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1099 			ret = -EPERM;
1100 		else {
1101 			if (val < 0)
1102 				ret = -EINVAL;
1103 			else
1104 				sk->sk_ll_usec = val;
1105 		}
1106 		break;
1107 #endif
1108 
1109 	case SO_MAX_PACING_RATE:
1110 		{
1111 		unsigned long ulval = (val == ~0U) ? ~0UL : val;
1112 
1113 		if (sizeof(ulval) != sizeof(val) &&
1114 		    optlen >= sizeof(ulval) &&
1115 		    get_user(ulval, (unsigned long __user *)optval)) {
1116 			ret = -EFAULT;
1117 			break;
1118 		}
1119 		if (ulval != ~0UL)
1120 			cmpxchg(&sk->sk_pacing_status,
1121 				SK_PACING_NONE,
1122 				SK_PACING_NEEDED);
1123 		sk->sk_max_pacing_rate = ulval;
1124 		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1125 		break;
1126 		}
1127 	case SO_INCOMING_CPU:
1128 		sk->sk_incoming_cpu = val;
1129 		break;
1130 
1131 	case SO_CNX_ADVICE:
1132 		if (val == 1)
1133 			dst_negative_advice(sk);
1134 		break;
1135 
1136 	case SO_ZEROCOPY:
1137 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1138 			if (!((sk->sk_type == SOCK_STREAM &&
1139 			       sk->sk_protocol == IPPROTO_TCP) ||
1140 			      (sk->sk_type == SOCK_DGRAM &&
1141 			       sk->sk_protocol == IPPROTO_UDP)))
1142 				ret = -ENOTSUPP;
1143 		} else if (sk->sk_family != PF_RDS) {
1144 			ret = -ENOTSUPP;
1145 		}
1146 		if (!ret) {
1147 			if (val < 0 || val > 1)
1148 				ret = -EINVAL;
1149 			else
1150 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1151 		}
1152 		break;
1153 
1154 	case SO_TXTIME:
1155 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1156 			ret = -EPERM;
1157 		} else if (optlen != sizeof(struct sock_txtime)) {
1158 			ret = -EINVAL;
1159 		} else if (copy_from_user(&sk_txtime, optval,
1160 			   sizeof(struct sock_txtime))) {
1161 			ret = -EFAULT;
1162 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1163 			ret = -EINVAL;
1164 		} else {
1165 			sock_valbool_flag(sk, SOCK_TXTIME, true);
1166 			sk->sk_clockid = sk_txtime.clockid;
1167 			sk->sk_txtime_deadline_mode =
1168 				!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1169 			sk->sk_txtime_report_errors =
1170 				!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1171 		}
1172 		break;
1173 
1174 	case SO_BINDTOIFINDEX:
1175 		ret = sock_setbindtodevice_locked(sk, val);
1176 		break;
1177 
1178 	default:
1179 		ret = -ENOPROTOOPT;
1180 		break;
1181 	}
1182 	release_sock(sk);
1183 	return ret;
1184 }
1185 EXPORT_SYMBOL(sock_setsockopt);
1186 
1187 
1188 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1189 			  struct ucred *ucred)
1190 {
1191 	ucred->pid = pid_vnr(pid);
1192 	ucred->uid = ucred->gid = -1;
1193 	if (cred) {
1194 		struct user_namespace *current_ns = current_user_ns();
1195 
1196 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1197 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1198 	}
1199 }
1200 
1201 static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1202 {
1203 	struct user_namespace *user_ns = current_user_ns();
1204 	int i;
1205 
1206 	for (i = 0; i < src->ngroups; i++)
1207 		if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1208 			return -EFAULT;
1209 
1210 	return 0;
1211 }
1212 
1213 int sock_getsockopt(struct socket *sock, int level, int optname,
1214 		    char __user *optval, int __user *optlen)
1215 {
1216 	struct sock *sk = sock->sk;
1217 
1218 	union {
1219 		int val;
1220 		u64 val64;
1221 		unsigned long ulval;
1222 		struct linger ling;
1223 		struct old_timeval32 tm32;
1224 		struct __kernel_old_timeval tm;
1225 		struct  __kernel_sock_timeval stm;
1226 		struct sock_txtime txtime;
1227 	} v;
1228 
1229 	int lv = sizeof(int);
1230 	int len;
1231 
1232 	if (get_user(len, optlen))
1233 		return -EFAULT;
1234 	if (len < 0)
1235 		return -EINVAL;
1236 
1237 	memset(&v, 0, sizeof(v));
1238 
1239 	switch (optname) {
1240 	case SO_DEBUG:
1241 		v.val = sock_flag(sk, SOCK_DBG);
1242 		break;
1243 
1244 	case SO_DONTROUTE:
1245 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1246 		break;
1247 
1248 	case SO_BROADCAST:
1249 		v.val = sock_flag(sk, SOCK_BROADCAST);
1250 		break;
1251 
1252 	case SO_SNDBUF:
1253 		v.val = sk->sk_sndbuf;
1254 		break;
1255 
1256 	case SO_RCVBUF:
1257 		v.val = sk->sk_rcvbuf;
1258 		break;
1259 
1260 	case SO_REUSEADDR:
1261 		v.val = sk->sk_reuse;
1262 		break;
1263 
1264 	case SO_REUSEPORT:
1265 		v.val = sk->sk_reuseport;
1266 		break;
1267 
1268 	case SO_KEEPALIVE:
1269 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1270 		break;
1271 
1272 	case SO_TYPE:
1273 		v.val = sk->sk_type;
1274 		break;
1275 
1276 	case SO_PROTOCOL:
1277 		v.val = sk->sk_protocol;
1278 		break;
1279 
1280 	case SO_DOMAIN:
1281 		v.val = sk->sk_family;
1282 		break;
1283 
1284 	case SO_ERROR:
1285 		v.val = -sock_error(sk);
1286 		if (v.val == 0)
1287 			v.val = xchg(&sk->sk_err_soft, 0);
1288 		break;
1289 
1290 	case SO_OOBINLINE:
1291 		v.val = sock_flag(sk, SOCK_URGINLINE);
1292 		break;
1293 
1294 	case SO_NO_CHECK:
1295 		v.val = sk->sk_no_check_tx;
1296 		break;
1297 
1298 	case SO_PRIORITY:
1299 		v.val = sk->sk_priority;
1300 		break;
1301 
1302 	case SO_LINGER:
1303 		lv		= sizeof(v.ling);
1304 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1305 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1306 		break;
1307 
1308 	case SO_BSDCOMPAT:
1309 		sock_warn_obsolete_bsdism("getsockopt");
1310 		break;
1311 
1312 	case SO_TIMESTAMP_OLD:
1313 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1314 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1315 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1316 		break;
1317 
1318 	case SO_TIMESTAMPNS_OLD:
1319 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1320 		break;
1321 
1322 	case SO_TIMESTAMP_NEW:
1323 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1324 		break;
1325 
1326 	case SO_TIMESTAMPNS_NEW:
1327 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1328 		break;
1329 
1330 	case SO_TIMESTAMPING_OLD:
1331 		v.val = sk->sk_tsflags;
1332 		break;
1333 
1334 	case SO_RCVTIMEO_OLD:
1335 	case SO_RCVTIMEO_NEW:
1336 		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1337 		break;
1338 
1339 	case SO_SNDTIMEO_OLD:
1340 	case SO_SNDTIMEO_NEW:
1341 		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1342 		break;
1343 
1344 	case SO_RCVLOWAT:
1345 		v.val = sk->sk_rcvlowat;
1346 		break;
1347 
1348 	case SO_SNDLOWAT:
1349 		v.val = 1;
1350 		break;
1351 
1352 	case SO_PASSCRED:
1353 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1354 		break;
1355 
1356 	case SO_PEERCRED:
1357 	{
1358 		struct ucred peercred;
1359 		if (len > sizeof(peercred))
1360 			len = sizeof(peercred);
1361 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1362 		if (copy_to_user(optval, &peercred, len))
1363 			return -EFAULT;
1364 		goto lenout;
1365 	}
1366 
1367 	case SO_PEERGROUPS:
1368 	{
1369 		int ret, n;
1370 
1371 		if (!sk->sk_peer_cred)
1372 			return -ENODATA;
1373 
1374 		n = sk->sk_peer_cred->group_info->ngroups;
1375 		if (len < n * sizeof(gid_t)) {
1376 			len = n * sizeof(gid_t);
1377 			return put_user(len, optlen) ? -EFAULT : -ERANGE;
1378 		}
1379 		len = n * sizeof(gid_t);
1380 
1381 		ret = groups_to_user((gid_t __user *)optval,
1382 				     sk->sk_peer_cred->group_info);
1383 		if (ret)
1384 			return ret;
1385 		goto lenout;
1386 	}
1387 
1388 	case SO_PEERNAME:
1389 	{
1390 		char address[128];
1391 
1392 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1393 		if (lv < 0)
1394 			return -ENOTCONN;
1395 		if (lv < len)
1396 			return -EINVAL;
1397 		if (copy_to_user(optval, address, len))
1398 			return -EFAULT;
1399 		goto lenout;
1400 	}
1401 
1402 	/* Dubious BSD thing... Probably nobody even uses it, but
1403 	 * the UNIX standard wants it for whatever reason... -DaveM
1404 	 */
1405 	case SO_ACCEPTCONN:
1406 		v.val = sk->sk_state == TCP_LISTEN;
1407 		break;
1408 
1409 	case SO_PASSSEC:
1410 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1411 		break;
1412 
1413 	case SO_PEERSEC:
1414 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1415 
1416 	case SO_MARK:
1417 		v.val = sk->sk_mark;
1418 		break;
1419 
1420 	case SO_RXQ_OVFL:
1421 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1422 		break;
1423 
1424 	case SO_WIFI_STATUS:
1425 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1426 		break;
1427 
1428 	case SO_PEEK_OFF:
1429 		if (!sock->ops->set_peek_off)
1430 			return -EOPNOTSUPP;
1431 
1432 		v.val = sk->sk_peek_off;
1433 		break;
1434 	case SO_NOFCS:
1435 		v.val = sock_flag(sk, SOCK_NOFCS);
1436 		break;
1437 
1438 	case SO_BINDTODEVICE:
1439 		return sock_getbindtodevice(sk, optval, optlen, len);
1440 
1441 	case SO_GET_FILTER:
1442 		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1443 		if (len < 0)
1444 			return len;
1445 
1446 		goto lenout;
1447 
1448 	case SO_LOCK_FILTER:
1449 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1450 		break;
1451 
1452 	case SO_BPF_EXTENSIONS:
1453 		v.val = bpf_tell_extensions();
1454 		break;
1455 
1456 	case SO_SELECT_ERR_QUEUE:
1457 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1458 		break;
1459 
1460 #ifdef CONFIG_NET_RX_BUSY_POLL
1461 	case SO_BUSY_POLL:
1462 		v.val = sk->sk_ll_usec;
1463 		break;
1464 #endif
1465 
1466 	case SO_MAX_PACING_RATE:
1467 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1468 			lv = sizeof(v.ulval);
1469 			v.ulval = sk->sk_max_pacing_rate;
1470 		} else {
1471 			/* 32bit version */
1472 			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1473 		}
1474 		break;
1475 
1476 	case SO_INCOMING_CPU:
1477 		v.val = sk->sk_incoming_cpu;
1478 		break;
1479 
1480 	case SO_MEMINFO:
1481 	{
1482 		u32 meminfo[SK_MEMINFO_VARS];
1483 
1484 		sk_get_meminfo(sk, meminfo);
1485 
1486 		len = min_t(unsigned int, len, sizeof(meminfo));
1487 		if (copy_to_user(optval, &meminfo, len))
1488 			return -EFAULT;
1489 
1490 		goto lenout;
1491 	}
1492 
1493 #ifdef CONFIG_NET_RX_BUSY_POLL
1494 	case SO_INCOMING_NAPI_ID:
1495 		v.val = READ_ONCE(sk->sk_napi_id);
1496 
1497 		/* aggregate non-NAPI IDs down to 0 */
1498 		if (v.val < MIN_NAPI_ID)
1499 			v.val = 0;
1500 
1501 		break;
1502 #endif
1503 
1504 	case SO_COOKIE:
1505 		lv = sizeof(u64);
1506 		if (len < lv)
1507 			return -EINVAL;
1508 		v.val64 = sock_gen_cookie(sk);
1509 		break;
1510 
1511 	case SO_ZEROCOPY:
1512 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1513 		break;
1514 
1515 	case SO_TXTIME:
1516 		lv = sizeof(v.txtime);
1517 		v.txtime.clockid = sk->sk_clockid;
1518 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1519 				  SOF_TXTIME_DEADLINE_MODE : 0;
1520 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1521 				  SOF_TXTIME_REPORT_ERRORS : 0;
1522 		break;
1523 
1524 	case SO_BINDTOIFINDEX:
1525 		v.val = sk->sk_bound_dev_if;
1526 		break;
1527 
1528 	default:
1529 		/* We implement the SO_SNDLOWAT etc to not be settable
1530 		 * (1003.1g 7).
1531 		 */
1532 		return -ENOPROTOOPT;
1533 	}
1534 
1535 	if (len > lv)
1536 		len = lv;
1537 	if (copy_to_user(optval, &v, len))
1538 		return -EFAULT;
1539 lenout:
1540 	if (put_user(len, optlen))
1541 		return -EFAULT;
1542 	return 0;
1543 }
1544 
1545 /*
1546  * Initialize an sk_lock.
1547  *
1548  * (We also register the sk_lock with the lock validator.)
1549  */
1550 static inline void sock_lock_init(struct sock *sk)
1551 {
1552 	if (sk->sk_kern_sock)
1553 		sock_lock_init_class_and_name(
1554 			sk,
1555 			af_family_kern_slock_key_strings[sk->sk_family],
1556 			af_family_kern_slock_keys + sk->sk_family,
1557 			af_family_kern_key_strings[sk->sk_family],
1558 			af_family_kern_keys + sk->sk_family);
1559 	else
1560 		sock_lock_init_class_and_name(
1561 			sk,
1562 			af_family_slock_key_strings[sk->sk_family],
1563 			af_family_slock_keys + sk->sk_family,
1564 			af_family_key_strings[sk->sk_family],
1565 			af_family_keys + sk->sk_family);
1566 }
1567 
1568 /*
1569  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1570  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1571  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1572  */
1573 static void sock_copy(struct sock *nsk, const struct sock *osk)
1574 {
1575 #ifdef CONFIG_SECURITY_NETWORK
1576 	void *sptr = nsk->sk_security;
1577 #endif
1578 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1579 
1580 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1581 	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1582 
1583 #ifdef CONFIG_SECURITY_NETWORK
1584 	nsk->sk_security = sptr;
1585 	security_sk_clone(osk, nsk);
1586 #endif
1587 }
1588 
1589 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1590 		int family)
1591 {
1592 	struct sock *sk;
1593 	struct kmem_cache *slab;
1594 
1595 	slab = prot->slab;
1596 	if (slab != NULL) {
1597 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1598 		if (!sk)
1599 			return sk;
1600 		if (want_init_on_alloc(priority))
1601 			sk_prot_clear_nulls(sk, prot->obj_size);
1602 	} else
1603 		sk = kmalloc(prot->obj_size, priority);
1604 
1605 	if (sk != NULL) {
1606 		if (security_sk_alloc(sk, family, priority))
1607 			goto out_free;
1608 
1609 		if (!try_module_get(prot->owner))
1610 			goto out_free_sec;
1611 		sk_tx_queue_clear(sk);
1612 	}
1613 
1614 	return sk;
1615 
1616 out_free_sec:
1617 	security_sk_free(sk);
1618 out_free:
1619 	if (slab != NULL)
1620 		kmem_cache_free(slab, sk);
1621 	else
1622 		kfree(sk);
1623 	return NULL;
1624 }
1625 
1626 static void sk_prot_free(struct proto *prot, struct sock *sk)
1627 {
1628 	struct kmem_cache *slab;
1629 	struct module *owner;
1630 
1631 	owner = prot->owner;
1632 	slab = prot->slab;
1633 
1634 	cgroup_sk_free(&sk->sk_cgrp_data);
1635 	mem_cgroup_sk_free(sk);
1636 	security_sk_free(sk);
1637 	if (slab != NULL)
1638 		kmem_cache_free(slab, sk);
1639 	else
1640 		kfree(sk);
1641 	module_put(owner);
1642 }
1643 
1644 /**
1645  *	sk_alloc - All socket objects are allocated here
1646  *	@net: the applicable net namespace
1647  *	@family: protocol family
1648  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1649  *	@prot: struct proto associated with this new sock instance
1650  *	@kern: is this to be a kernel socket?
1651  */
1652 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1653 		      struct proto *prot, int kern)
1654 {
1655 	struct sock *sk;
1656 
1657 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1658 	if (sk) {
1659 		sk->sk_family = family;
1660 		/*
1661 		 * See comment in struct sock definition to understand
1662 		 * why we need sk_prot_creator -acme
1663 		 */
1664 		sk->sk_prot = sk->sk_prot_creator = prot;
1665 		sk->sk_kern_sock = kern;
1666 		sock_lock_init(sk);
1667 		sk->sk_net_refcnt = kern ? 0 : 1;
1668 		if (likely(sk->sk_net_refcnt)) {
1669 			get_net(net);
1670 			sock_inuse_add(net, 1);
1671 		}
1672 
1673 		sock_net_set(sk, net);
1674 		refcount_set(&sk->sk_wmem_alloc, 1);
1675 
1676 		mem_cgroup_sk_alloc(sk);
1677 		cgroup_sk_alloc(&sk->sk_cgrp_data);
1678 		sock_update_classid(&sk->sk_cgrp_data);
1679 		sock_update_netprioidx(&sk->sk_cgrp_data);
1680 	}
1681 
1682 	return sk;
1683 }
1684 EXPORT_SYMBOL(sk_alloc);
1685 
1686 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
1687  * grace period. This is the case for UDP sockets and TCP listeners.
1688  */
1689 static void __sk_destruct(struct rcu_head *head)
1690 {
1691 	struct sock *sk = container_of(head, struct sock, sk_rcu);
1692 	struct sk_filter *filter;
1693 
1694 	if (sk->sk_destruct)
1695 		sk->sk_destruct(sk);
1696 
1697 	filter = rcu_dereference_check(sk->sk_filter,
1698 				       refcount_read(&sk->sk_wmem_alloc) == 0);
1699 	if (filter) {
1700 		sk_filter_uncharge(sk, filter);
1701 		RCU_INIT_POINTER(sk->sk_filter, NULL);
1702 	}
1703 	if (rcu_access_pointer(sk->sk_reuseport_cb))
1704 		reuseport_detach_sock(sk);
1705 
1706 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1707 
1708 #ifdef CONFIG_BPF_SYSCALL
1709 	bpf_sk_storage_free(sk);
1710 #endif
1711 
1712 	if (atomic_read(&sk->sk_omem_alloc))
1713 		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1714 			 __func__, atomic_read(&sk->sk_omem_alloc));
1715 
1716 	if (sk->sk_frag.page) {
1717 		put_page(sk->sk_frag.page);
1718 		sk->sk_frag.page = NULL;
1719 	}
1720 
1721 	if (sk->sk_peer_cred)
1722 		put_cred(sk->sk_peer_cred);
1723 	put_pid(sk->sk_peer_pid);
1724 	if (likely(sk->sk_net_refcnt))
1725 		put_net(sock_net(sk));
1726 	sk_prot_free(sk->sk_prot_creator, sk);
1727 }
1728 
1729 void sk_destruct(struct sock *sk)
1730 {
1731 	if (sock_flag(sk, SOCK_RCU_FREE))
1732 		call_rcu(&sk->sk_rcu, __sk_destruct);
1733 	else
1734 		__sk_destruct(&sk->sk_rcu);
1735 }
1736 
1737 static void __sk_free(struct sock *sk)
1738 {
1739 	if (likely(sk->sk_net_refcnt))
1740 		sock_inuse_add(sock_net(sk), -1);
1741 
1742 	if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
1743 		sock_diag_broadcast_destroy(sk);
1744 	else
1745 		sk_destruct(sk);
1746 }
1747 
1748 void sk_free(struct sock *sk)
1749 {
1750 	/*
1751 	 * We subtract one from sk_wmem_alloc and can know if
1752 	 * some packets are still in some tx queue.
1753 	 * If not null, sock_wfree() will call __sk_free(sk) later
1754 	 */
1755 	if (refcount_dec_and_test(&sk->sk_wmem_alloc))
1756 		__sk_free(sk);
1757 }
1758 EXPORT_SYMBOL(sk_free);
1759 
1760 static void sk_init_common(struct sock *sk)
1761 {
1762 	skb_queue_head_init(&sk->sk_receive_queue);
1763 	skb_queue_head_init(&sk->sk_write_queue);
1764 	skb_queue_head_init(&sk->sk_error_queue);
1765 
1766 	rwlock_init(&sk->sk_callback_lock);
1767 	lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
1768 			af_rlock_keys + sk->sk_family,
1769 			af_family_rlock_key_strings[sk->sk_family]);
1770 	lockdep_set_class_and_name(&sk->sk_write_queue.lock,
1771 			af_wlock_keys + sk->sk_family,
1772 			af_family_wlock_key_strings[sk->sk_family]);
1773 	lockdep_set_class_and_name(&sk->sk_error_queue.lock,
1774 			af_elock_keys + sk->sk_family,
1775 			af_family_elock_key_strings[sk->sk_family]);
1776 	lockdep_set_class_and_name(&sk->sk_callback_lock,
1777 			af_callback_keys + sk->sk_family,
1778 			af_family_clock_key_strings[sk->sk_family]);
1779 }
1780 
1781 /**
1782  *	sk_clone_lock - clone a socket, and lock its clone
1783  *	@sk: the socket to clone
1784  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1785  *
1786  *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1787  */
1788 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1789 {
1790 	struct sock *newsk;
1791 	bool is_charged = true;
1792 
1793 	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1794 	if (newsk != NULL) {
1795 		struct sk_filter *filter;
1796 
1797 		sock_copy(newsk, sk);
1798 
1799 		newsk->sk_prot_creator = sk->sk_prot;
1800 
1801 		/* SANITY */
1802 		if (likely(newsk->sk_net_refcnt))
1803 			get_net(sock_net(newsk));
1804 		sk_node_init(&newsk->sk_node);
1805 		sock_lock_init(newsk);
1806 		bh_lock_sock(newsk);
1807 		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1808 		newsk->sk_backlog.len = 0;
1809 
1810 		atomic_set(&newsk->sk_rmem_alloc, 0);
1811 		/*
1812 		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1813 		 */
1814 		refcount_set(&newsk->sk_wmem_alloc, 1);
1815 		atomic_set(&newsk->sk_omem_alloc, 0);
1816 		sk_init_common(newsk);
1817 
1818 		newsk->sk_dst_cache	= NULL;
1819 		newsk->sk_dst_pending_confirm = 0;
1820 		newsk->sk_wmem_queued	= 0;
1821 		newsk->sk_forward_alloc = 0;
1822 		atomic_set(&newsk->sk_drops, 0);
1823 		newsk->sk_send_head	= NULL;
1824 		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1825 		atomic_set(&newsk->sk_zckey, 0);
1826 
1827 		sock_reset_flag(newsk, SOCK_DONE);
1828 		mem_cgroup_sk_alloc(newsk);
1829 		cgroup_sk_alloc(&newsk->sk_cgrp_data);
1830 
1831 		rcu_read_lock();
1832 		filter = rcu_dereference(sk->sk_filter);
1833 		if (filter != NULL)
1834 			/* though it's an empty new sock, the charging may fail
1835 			 * if sysctl_optmem_max was changed between creation of
1836 			 * original socket and cloning
1837 			 */
1838 			is_charged = sk_filter_charge(newsk, filter);
1839 		RCU_INIT_POINTER(newsk->sk_filter, filter);
1840 		rcu_read_unlock();
1841 
1842 		if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1843 			/* We need to make sure that we don't uncharge the new
1844 			 * socket if we couldn't charge it in the first place
1845 			 * as otherwise we uncharge the parent's filter.
1846 			 */
1847 			if (!is_charged)
1848 				RCU_INIT_POINTER(newsk->sk_filter, NULL);
1849 			sk_free_unlock_clone(newsk);
1850 			newsk = NULL;
1851 			goto out;
1852 		}
1853 		RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1854 #ifdef CONFIG_BPF_SYSCALL
1855 		RCU_INIT_POINTER(newsk->sk_bpf_storage, NULL);
1856 #endif
1857 
1858 		newsk->sk_err	   = 0;
1859 		newsk->sk_err_soft = 0;
1860 		newsk->sk_priority = 0;
1861 		newsk->sk_incoming_cpu = raw_smp_processor_id();
1862 		if (likely(newsk->sk_net_refcnt))
1863 			sock_inuse_add(sock_net(newsk), 1);
1864 
1865 		/*
1866 		 * Before updating sk_refcnt, we must commit prior changes to memory
1867 		 * (Documentation/RCU/rculist_nulls.txt for details)
1868 		 */
1869 		smp_wmb();
1870 		refcount_set(&newsk->sk_refcnt, 2);
1871 
1872 		/*
1873 		 * Increment the counter in the same struct proto as the master
1874 		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1875 		 * is the same as sk->sk_prot->socks, as this field was copied
1876 		 * with memcpy).
1877 		 *
1878 		 * This _changes_ the previous behaviour, where
1879 		 * tcp_create_openreq_child always was incrementing the
1880 		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1881 		 * to be taken into account in all callers. -acme
1882 		 */
1883 		sk_refcnt_debug_inc(newsk);
1884 		sk_set_socket(newsk, NULL);
1885 		RCU_INIT_POINTER(newsk->sk_wq, NULL);
1886 
1887 		if (newsk->sk_prot->sockets_allocated)
1888 			sk_sockets_allocated_inc(newsk);
1889 
1890 		if (sock_needs_netstamp(sk) &&
1891 		    newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1892 			net_enable_timestamp();
1893 	}
1894 out:
1895 	return newsk;
1896 }
1897 EXPORT_SYMBOL_GPL(sk_clone_lock);
1898 
1899 void sk_free_unlock_clone(struct sock *sk)
1900 {
1901 	/* It is still raw copy of parent, so invalidate
1902 	 * destructor and make plain sk_free() */
1903 	sk->sk_destruct = NULL;
1904 	bh_unlock_sock(sk);
1905 	sk_free(sk);
1906 }
1907 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
1908 
1909 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1910 {
1911 	u32 max_segs = 1;
1912 
1913 	sk_dst_set(sk, dst);
1914 	sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps;
1915 	if (sk->sk_route_caps & NETIF_F_GSO)
1916 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1917 	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1918 	if (sk_can_gso(sk)) {
1919 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
1920 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1921 		} else {
1922 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1923 			sk->sk_gso_max_size = dst->dev->gso_max_size;
1924 			max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1925 		}
1926 	}
1927 	sk->sk_gso_max_segs = max_segs;
1928 }
1929 EXPORT_SYMBOL_GPL(sk_setup_caps);
1930 
1931 /*
1932  *	Simple resource managers for sockets.
1933  */
1934 
1935 
1936 /*
1937  * Write buffer destructor automatically called from kfree_skb.
1938  */
1939 void sock_wfree(struct sk_buff *skb)
1940 {
1941 	struct sock *sk = skb->sk;
1942 	unsigned int len = skb->truesize;
1943 
1944 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1945 		/*
1946 		 * Keep a reference on sk_wmem_alloc, this will be released
1947 		 * after sk_write_space() call
1948 		 */
1949 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
1950 		sk->sk_write_space(sk);
1951 		len = 1;
1952 	}
1953 	/*
1954 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1955 	 * could not do because of in-flight packets
1956 	 */
1957 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
1958 		__sk_free(sk);
1959 }
1960 EXPORT_SYMBOL(sock_wfree);
1961 
1962 /* This variant of sock_wfree() is used by TCP,
1963  * since it sets SOCK_USE_WRITE_QUEUE.
1964  */
1965 void __sock_wfree(struct sk_buff *skb)
1966 {
1967 	struct sock *sk = skb->sk;
1968 
1969 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
1970 		__sk_free(sk);
1971 }
1972 
1973 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1974 {
1975 	skb_orphan(skb);
1976 	skb->sk = sk;
1977 #ifdef CONFIG_INET
1978 	if (unlikely(!sk_fullsock(sk))) {
1979 		skb->destructor = sock_edemux;
1980 		sock_hold(sk);
1981 		return;
1982 	}
1983 #endif
1984 	skb->destructor = sock_wfree;
1985 	skb_set_hash_from_sk(skb, sk);
1986 	/*
1987 	 * We used to take a refcount on sk, but following operation
1988 	 * is enough to guarantee sk_free() wont free this sock until
1989 	 * all in-flight packets are completed
1990 	 */
1991 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
1992 }
1993 EXPORT_SYMBOL(skb_set_owner_w);
1994 
1995 /* This helper is used by netem, as it can hold packets in its
1996  * delay queue. We want to allow the owner socket to send more
1997  * packets, as if they were already TX completed by a typical driver.
1998  * But we also want to keep skb->sk set because some packet schedulers
1999  * rely on it (sch_fq for example).
2000  */
2001 void skb_orphan_partial(struct sk_buff *skb)
2002 {
2003 	if (skb_is_tcp_pure_ack(skb))
2004 		return;
2005 
2006 	if (skb->destructor == sock_wfree
2007 #ifdef CONFIG_INET
2008 	    || skb->destructor == tcp_wfree
2009 #endif
2010 		) {
2011 		struct sock *sk = skb->sk;
2012 
2013 		if (refcount_inc_not_zero(&sk->sk_refcnt)) {
2014 			WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc));
2015 			skb->destructor = sock_efree;
2016 		}
2017 	} else {
2018 		skb_orphan(skb);
2019 	}
2020 }
2021 EXPORT_SYMBOL(skb_orphan_partial);
2022 
2023 /*
2024  * Read buffer destructor automatically called from kfree_skb.
2025  */
2026 void sock_rfree(struct sk_buff *skb)
2027 {
2028 	struct sock *sk = skb->sk;
2029 	unsigned int len = skb->truesize;
2030 
2031 	atomic_sub(len, &sk->sk_rmem_alloc);
2032 	sk_mem_uncharge(sk, len);
2033 }
2034 EXPORT_SYMBOL(sock_rfree);
2035 
2036 /*
2037  * Buffer destructor for skbs that are not used directly in read or write
2038  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2039  */
2040 void sock_efree(struct sk_buff *skb)
2041 {
2042 	sock_put(skb->sk);
2043 }
2044 EXPORT_SYMBOL(sock_efree);
2045 
2046 kuid_t sock_i_uid(struct sock *sk)
2047 {
2048 	kuid_t uid;
2049 
2050 	read_lock_bh(&sk->sk_callback_lock);
2051 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2052 	read_unlock_bh(&sk->sk_callback_lock);
2053 	return uid;
2054 }
2055 EXPORT_SYMBOL(sock_i_uid);
2056 
2057 unsigned long sock_i_ino(struct sock *sk)
2058 {
2059 	unsigned long ino;
2060 
2061 	read_lock_bh(&sk->sk_callback_lock);
2062 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2063 	read_unlock_bh(&sk->sk_callback_lock);
2064 	return ino;
2065 }
2066 EXPORT_SYMBOL(sock_i_ino);
2067 
2068 /*
2069  * Allocate a skb from the socket's send buffer.
2070  */
2071 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2072 			     gfp_t priority)
2073 {
2074 	if (force || refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
2075 		struct sk_buff *skb = alloc_skb(size, priority);
2076 		if (skb) {
2077 			skb_set_owner_w(skb, sk);
2078 			return skb;
2079 		}
2080 	}
2081 	return NULL;
2082 }
2083 EXPORT_SYMBOL(sock_wmalloc);
2084 
2085 static void sock_ofree(struct sk_buff *skb)
2086 {
2087 	struct sock *sk = skb->sk;
2088 
2089 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2090 }
2091 
2092 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2093 			     gfp_t priority)
2094 {
2095 	struct sk_buff *skb;
2096 
2097 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2098 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2099 	    sysctl_optmem_max)
2100 		return NULL;
2101 
2102 	skb = alloc_skb(size, priority);
2103 	if (!skb)
2104 		return NULL;
2105 
2106 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2107 	skb->sk = sk;
2108 	skb->destructor = sock_ofree;
2109 	return skb;
2110 }
2111 
2112 /*
2113  * Allocate a memory block from the socket's option memory buffer.
2114  */
2115 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2116 {
2117 	if ((unsigned int)size <= sysctl_optmem_max &&
2118 	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
2119 		void *mem;
2120 		/* First do the add, to avoid the race if kmalloc
2121 		 * might sleep.
2122 		 */
2123 		atomic_add(size, &sk->sk_omem_alloc);
2124 		mem = kmalloc(size, priority);
2125 		if (mem)
2126 			return mem;
2127 		atomic_sub(size, &sk->sk_omem_alloc);
2128 	}
2129 	return NULL;
2130 }
2131 EXPORT_SYMBOL(sock_kmalloc);
2132 
2133 /* Free an option memory block. Note, we actually want the inline
2134  * here as this allows gcc to detect the nullify and fold away the
2135  * condition entirely.
2136  */
2137 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2138 				  const bool nullify)
2139 {
2140 	if (WARN_ON_ONCE(!mem))
2141 		return;
2142 	if (nullify)
2143 		kzfree(mem);
2144 	else
2145 		kfree(mem);
2146 	atomic_sub(size, &sk->sk_omem_alloc);
2147 }
2148 
2149 void sock_kfree_s(struct sock *sk, void *mem, int size)
2150 {
2151 	__sock_kfree_s(sk, mem, size, false);
2152 }
2153 EXPORT_SYMBOL(sock_kfree_s);
2154 
2155 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2156 {
2157 	__sock_kfree_s(sk, mem, size, true);
2158 }
2159 EXPORT_SYMBOL(sock_kzfree_s);
2160 
2161 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2162    I think, these locks should be removed for datagram sockets.
2163  */
2164 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2165 {
2166 	DEFINE_WAIT(wait);
2167 
2168 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2169 	for (;;) {
2170 		if (!timeo)
2171 			break;
2172 		if (signal_pending(current))
2173 			break;
2174 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2175 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2176 		if (refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
2177 			break;
2178 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2179 			break;
2180 		if (sk->sk_err)
2181 			break;
2182 		timeo = schedule_timeout(timeo);
2183 	}
2184 	finish_wait(sk_sleep(sk), &wait);
2185 	return timeo;
2186 }
2187 
2188 
2189 /*
2190  *	Generic send/receive buffer handlers
2191  */
2192 
2193 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2194 				     unsigned long data_len, int noblock,
2195 				     int *errcode, int max_page_order)
2196 {
2197 	struct sk_buff *skb;
2198 	long timeo;
2199 	int err;
2200 
2201 	timeo = sock_sndtimeo(sk, noblock);
2202 	for (;;) {
2203 		err = sock_error(sk);
2204 		if (err != 0)
2205 			goto failure;
2206 
2207 		err = -EPIPE;
2208 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2209 			goto failure;
2210 
2211 		if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
2212 			break;
2213 
2214 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2215 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2216 		err = -EAGAIN;
2217 		if (!timeo)
2218 			goto failure;
2219 		if (signal_pending(current))
2220 			goto interrupted;
2221 		timeo = sock_wait_for_wmem(sk, timeo);
2222 	}
2223 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2224 				   errcode, sk->sk_allocation);
2225 	if (skb)
2226 		skb_set_owner_w(skb, sk);
2227 	return skb;
2228 
2229 interrupted:
2230 	err = sock_intr_errno(timeo);
2231 failure:
2232 	*errcode = err;
2233 	return NULL;
2234 }
2235 EXPORT_SYMBOL(sock_alloc_send_pskb);
2236 
2237 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2238 				    int noblock, int *errcode)
2239 {
2240 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2241 }
2242 EXPORT_SYMBOL(sock_alloc_send_skb);
2243 
2244 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2245 		     struct sockcm_cookie *sockc)
2246 {
2247 	u32 tsflags;
2248 
2249 	switch (cmsg->cmsg_type) {
2250 	case SO_MARK:
2251 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2252 			return -EPERM;
2253 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2254 			return -EINVAL;
2255 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2256 		break;
2257 	case SO_TIMESTAMPING_OLD:
2258 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2259 			return -EINVAL;
2260 
2261 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2262 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2263 			return -EINVAL;
2264 
2265 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2266 		sockc->tsflags |= tsflags;
2267 		break;
2268 	case SCM_TXTIME:
2269 		if (!sock_flag(sk, SOCK_TXTIME))
2270 			return -EINVAL;
2271 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2272 			return -EINVAL;
2273 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2274 		break;
2275 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2276 	case SCM_RIGHTS:
2277 	case SCM_CREDENTIALS:
2278 		break;
2279 	default:
2280 		return -EINVAL;
2281 	}
2282 	return 0;
2283 }
2284 EXPORT_SYMBOL(__sock_cmsg_send);
2285 
2286 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2287 		   struct sockcm_cookie *sockc)
2288 {
2289 	struct cmsghdr *cmsg;
2290 	int ret;
2291 
2292 	for_each_cmsghdr(cmsg, msg) {
2293 		if (!CMSG_OK(msg, cmsg))
2294 			return -EINVAL;
2295 		if (cmsg->cmsg_level != SOL_SOCKET)
2296 			continue;
2297 		ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2298 		if (ret)
2299 			return ret;
2300 	}
2301 	return 0;
2302 }
2303 EXPORT_SYMBOL(sock_cmsg_send);
2304 
2305 static void sk_enter_memory_pressure(struct sock *sk)
2306 {
2307 	if (!sk->sk_prot->enter_memory_pressure)
2308 		return;
2309 
2310 	sk->sk_prot->enter_memory_pressure(sk);
2311 }
2312 
2313 static void sk_leave_memory_pressure(struct sock *sk)
2314 {
2315 	if (sk->sk_prot->leave_memory_pressure) {
2316 		sk->sk_prot->leave_memory_pressure(sk);
2317 	} else {
2318 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2319 
2320 		if (memory_pressure && *memory_pressure)
2321 			*memory_pressure = 0;
2322 	}
2323 }
2324 
2325 /* On 32bit arches, an skb frag is limited to 2^15 */
2326 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2327 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2328 
2329 /**
2330  * skb_page_frag_refill - check that a page_frag contains enough room
2331  * @sz: minimum size of the fragment we want to get
2332  * @pfrag: pointer to page_frag
2333  * @gfp: priority for memory allocation
2334  *
2335  * Note: While this allocator tries to use high order pages, there is
2336  * no guarantee that allocations succeed. Therefore, @sz MUST be
2337  * less or equal than PAGE_SIZE.
2338  */
2339 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2340 {
2341 	if (pfrag->page) {
2342 		if (page_ref_count(pfrag->page) == 1) {
2343 			pfrag->offset = 0;
2344 			return true;
2345 		}
2346 		if (pfrag->offset + sz <= pfrag->size)
2347 			return true;
2348 		put_page(pfrag->page);
2349 	}
2350 
2351 	pfrag->offset = 0;
2352 	if (SKB_FRAG_PAGE_ORDER &&
2353 	    !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2354 		/* Avoid direct reclaim but allow kswapd to wake */
2355 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2356 					  __GFP_COMP | __GFP_NOWARN |
2357 					  __GFP_NORETRY,
2358 					  SKB_FRAG_PAGE_ORDER);
2359 		if (likely(pfrag->page)) {
2360 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2361 			return true;
2362 		}
2363 	}
2364 	pfrag->page = alloc_page(gfp);
2365 	if (likely(pfrag->page)) {
2366 		pfrag->size = PAGE_SIZE;
2367 		return true;
2368 	}
2369 	return false;
2370 }
2371 EXPORT_SYMBOL(skb_page_frag_refill);
2372 
2373 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2374 {
2375 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2376 		return true;
2377 
2378 	sk_enter_memory_pressure(sk);
2379 	sk_stream_moderate_sndbuf(sk);
2380 	return false;
2381 }
2382 EXPORT_SYMBOL(sk_page_frag_refill);
2383 
2384 static void __lock_sock(struct sock *sk)
2385 	__releases(&sk->sk_lock.slock)
2386 	__acquires(&sk->sk_lock.slock)
2387 {
2388 	DEFINE_WAIT(wait);
2389 
2390 	for (;;) {
2391 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2392 					TASK_UNINTERRUPTIBLE);
2393 		spin_unlock_bh(&sk->sk_lock.slock);
2394 		schedule();
2395 		spin_lock_bh(&sk->sk_lock.slock);
2396 		if (!sock_owned_by_user(sk))
2397 			break;
2398 	}
2399 	finish_wait(&sk->sk_lock.wq, &wait);
2400 }
2401 
2402 void __release_sock(struct sock *sk)
2403 	__releases(&sk->sk_lock.slock)
2404 	__acquires(&sk->sk_lock.slock)
2405 {
2406 	struct sk_buff *skb, *next;
2407 
2408 	while ((skb = sk->sk_backlog.head) != NULL) {
2409 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2410 
2411 		spin_unlock_bh(&sk->sk_lock.slock);
2412 
2413 		do {
2414 			next = skb->next;
2415 			prefetch(next);
2416 			WARN_ON_ONCE(skb_dst_is_noref(skb));
2417 			skb_mark_not_on_list(skb);
2418 			sk_backlog_rcv(sk, skb);
2419 
2420 			cond_resched();
2421 
2422 			skb = next;
2423 		} while (skb != NULL);
2424 
2425 		spin_lock_bh(&sk->sk_lock.slock);
2426 	}
2427 
2428 	/*
2429 	 * Doing the zeroing here guarantee we can not loop forever
2430 	 * while a wild producer attempts to flood us.
2431 	 */
2432 	sk->sk_backlog.len = 0;
2433 }
2434 
2435 void __sk_flush_backlog(struct sock *sk)
2436 {
2437 	spin_lock_bh(&sk->sk_lock.slock);
2438 	__release_sock(sk);
2439 	spin_unlock_bh(&sk->sk_lock.slock);
2440 }
2441 
2442 /**
2443  * sk_wait_data - wait for data to arrive at sk_receive_queue
2444  * @sk:    sock to wait on
2445  * @timeo: for how long
2446  * @skb:   last skb seen on sk_receive_queue
2447  *
2448  * Now socket state including sk->sk_err is changed only under lock,
2449  * hence we may omit checks after joining wait queue.
2450  * We check receive queue before schedule() only as optimization;
2451  * it is very likely that release_sock() added new data.
2452  */
2453 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2454 {
2455 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2456 	int rc;
2457 
2458 	add_wait_queue(sk_sleep(sk), &wait);
2459 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2460 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2461 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2462 	remove_wait_queue(sk_sleep(sk), &wait);
2463 	return rc;
2464 }
2465 EXPORT_SYMBOL(sk_wait_data);
2466 
2467 /**
2468  *	__sk_mem_raise_allocated - increase memory_allocated
2469  *	@sk: socket
2470  *	@size: memory size to allocate
2471  *	@amt: pages to allocate
2472  *	@kind: allocation type
2473  *
2474  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2475  */
2476 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2477 {
2478 	struct proto *prot = sk->sk_prot;
2479 	long allocated = sk_memory_allocated_add(sk, amt);
2480 	bool charged = true;
2481 
2482 	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2483 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt)))
2484 		goto suppress_allocation;
2485 
2486 	/* Under limit. */
2487 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2488 		sk_leave_memory_pressure(sk);
2489 		return 1;
2490 	}
2491 
2492 	/* Under pressure. */
2493 	if (allocated > sk_prot_mem_limits(sk, 1))
2494 		sk_enter_memory_pressure(sk);
2495 
2496 	/* Over hard limit. */
2497 	if (allocated > sk_prot_mem_limits(sk, 2))
2498 		goto suppress_allocation;
2499 
2500 	/* guarantee minimum buffer size under pressure */
2501 	if (kind == SK_MEM_RECV) {
2502 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2503 			return 1;
2504 
2505 	} else { /* SK_MEM_SEND */
2506 		int wmem0 = sk_get_wmem0(sk, prot);
2507 
2508 		if (sk->sk_type == SOCK_STREAM) {
2509 			if (sk->sk_wmem_queued < wmem0)
2510 				return 1;
2511 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
2512 				return 1;
2513 		}
2514 	}
2515 
2516 	if (sk_has_memory_pressure(sk)) {
2517 		u64 alloc;
2518 
2519 		if (!sk_under_memory_pressure(sk))
2520 			return 1;
2521 		alloc = sk_sockets_allocated_read_positive(sk);
2522 		if (sk_prot_mem_limits(sk, 2) > alloc *
2523 		    sk_mem_pages(sk->sk_wmem_queued +
2524 				 atomic_read(&sk->sk_rmem_alloc) +
2525 				 sk->sk_forward_alloc))
2526 			return 1;
2527 	}
2528 
2529 suppress_allocation:
2530 
2531 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2532 		sk_stream_moderate_sndbuf(sk);
2533 
2534 		/* Fail only if socket is _under_ its sndbuf.
2535 		 * In this case we cannot block, so that we have to fail.
2536 		 */
2537 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2538 			return 1;
2539 	}
2540 
2541 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
2542 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
2543 
2544 	sk_memory_allocated_sub(sk, amt);
2545 
2546 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2547 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2548 
2549 	return 0;
2550 }
2551 EXPORT_SYMBOL(__sk_mem_raise_allocated);
2552 
2553 /**
2554  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2555  *	@sk: socket
2556  *	@size: memory size to allocate
2557  *	@kind: allocation type
2558  *
2559  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2560  *	rmem allocation. This function assumes that protocols which have
2561  *	memory_pressure use sk_wmem_queued as write buffer accounting.
2562  */
2563 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2564 {
2565 	int ret, amt = sk_mem_pages(size);
2566 
2567 	sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2568 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2569 	if (!ret)
2570 		sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2571 	return ret;
2572 }
2573 EXPORT_SYMBOL(__sk_mem_schedule);
2574 
2575 /**
2576  *	__sk_mem_reduce_allocated - reclaim memory_allocated
2577  *	@sk: socket
2578  *	@amount: number of quanta
2579  *
2580  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2581  */
2582 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2583 {
2584 	sk_memory_allocated_sub(sk, amount);
2585 
2586 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2587 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2588 
2589 	if (sk_under_memory_pressure(sk) &&
2590 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2591 		sk_leave_memory_pressure(sk);
2592 }
2593 EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2594 
2595 /**
2596  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2597  *	@sk: socket
2598  *	@amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2599  */
2600 void __sk_mem_reclaim(struct sock *sk, int amount)
2601 {
2602 	amount >>= SK_MEM_QUANTUM_SHIFT;
2603 	sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2604 	__sk_mem_reduce_allocated(sk, amount);
2605 }
2606 EXPORT_SYMBOL(__sk_mem_reclaim);
2607 
2608 int sk_set_peek_off(struct sock *sk, int val)
2609 {
2610 	sk->sk_peek_off = val;
2611 	return 0;
2612 }
2613 EXPORT_SYMBOL_GPL(sk_set_peek_off);
2614 
2615 /*
2616  * Set of default routines for initialising struct proto_ops when
2617  * the protocol does not support a particular function. In certain
2618  * cases where it makes no sense for a protocol to have a "do nothing"
2619  * function, some default processing is provided.
2620  */
2621 
2622 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2623 {
2624 	return -EOPNOTSUPP;
2625 }
2626 EXPORT_SYMBOL(sock_no_bind);
2627 
2628 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2629 		    int len, int flags)
2630 {
2631 	return -EOPNOTSUPP;
2632 }
2633 EXPORT_SYMBOL(sock_no_connect);
2634 
2635 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2636 {
2637 	return -EOPNOTSUPP;
2638 }
2639 EXPORT_SYMBOL(sock_no_socketpair);
2640 
2641 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2642 		   bool kern)
2643 {
2644 	return -EOPNOTSUPP;
2645 }
2646 EXPORT_SYMBOL(sock_no_accept);
2647 
2648 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2649 		    int peer)
2650 {
2651 	return -EOPNOTSUPP;
2652 }
2653 EXPORT_SYMBOL(sock_no_getname);
2654 
2655 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2656 {
2657 	return -EOPNOTSUPP;
2658 }
2659 EXPORT_SYMBOL(sock_no_ioctl);
2660 
2661 int sock_no_listen(struct socket *sock, int backlog)
2662 {
2663 	return -EOPNOTSUPP;
2664 }
2665 EXPORT_SYMBOL(sock_no_listen);
2666 
2667 int sock_no_shutdown(struct socket *sock, int how)
2668 {
2669 	return -EOPNOTSUPP;
2670 }
2671 EXPORT_SYMBOL(sock_no_shutdown);
2672 
2673 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2674 		    char __user *optval, unsigned int optlen)
2675 {
2676 	return -EOPNOTSUPP;
2677 }
2678 EXPORT_SYMBOL(sock_no_setsockopt);
2679 
2680 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2681 		    char __user *optval, int __user *optlen)
2682 {
2683 	return -EOPNOTSUPP;
2684 }
2685 EXPORT_SYMBOL(sock_no_getsockopt);
2686 
2687 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2688 {
2689 	return -EOPNOTSUPP;
2690 }
2691 EXPORT_SYMBOL(sock_no_sendmsg);
2692 
2693 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
2694 {
2695 	return -EOPNOTSUPP;
2696 }
2697 EXPORT_SYMBOL(sock_no_sendmsg_locked);
2698 
2699 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2700 		    int flags)
2701 {
2702 	return -EOPNOTSUPP;
2703 }
2704 EXPORT_SYMBOL(sock_no_recvmsg);
2705 
2706 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2707 {
2708 	/* Mirror missing mmap method error code */
2709 	return -ENODEV;
2710 }
2711 EXPORT_SYMBOL(sock_no_mmap);
2712 
2713 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2714 {
2715 	ssize_t res;
2716 	struct msghdr msg = {.msg_flags = flags};
2717 	struct kvec iov;
2718 	char *kaddr = kmap(page);
2719 	iov.iov_base = kaddr + offset;
2720 	iov.iov_len = size;
2721 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2722 	kunmap(page);
2723 	return res;
2724 }
2725 EXPORT_SYMBOL(sock_no_sendpage);
2726 
2727 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
2728 				int offset, size_t size, int flags)
2729 {
2730 	ssize_t res;
2731 	struct msghdr msg = {.msg_flags = flags};
2732 	struct kvec iov;
2733 	char *kaddr = kmap(page);
2734 
2735 	iov.iov_base = kaddr + offset;
2736 	iov.iov_len = size;
2737 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
2738 	kunmap(page);
2739 	return res;
2740 }
2741 EXPORT_SYMBOL(sock_no_sendpage_locked);
2742 
2743 /*
2744  *	Default Socket Callbacks
2745  */
2746 
2747 static void sock_def_wakeup(struct sock *sk)
2748 {
2749 	struct socket_wq *wq;
2750 
2751 	rcu_read_lock();
2752 	wq = rcu_dereference(sk->sk_wq);
2753 	if (skwq_has_sleeper(wq))
2754 		wake_up_interruptible_all(&wq->wait);
2755 	rcu_read_unlock();
2756 }
2757 
2758 static void sock_def_error_report(struct sock *sk)
2759 {
2760 	struct socket_wq *wq;
2761 
2762 	rcu_read_lock();
2763 	wq = rcu_dereference(sk->sk_wq);
2764 	if (skwq_has_sleeper(wq))
2765 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
2766 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2767 	rcu_read_unlock();
2768 }
2769 
2770 static void sock_def_readable(struct sock *sk)
2771 {
2772 	struct socket_wq *wq;
2773 
2774 	rcu_read_lock();
2775 	wq = rcu_dereference(sk->sk_wq);
2776 	if (skwq_has_sleeper(wq))
2777 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
2778 						EPOLLRDNORM | EPOLLRDBAND);
2779 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2780 	rcu_read_unlock();
2781 }
2782 
2783 static void sock_def_write_space(struct sock *sk)
2784 {
2785 	struct socket_wq *wq;
2786 
2787 	rcu_read_lock();
2788 
2789 	/* Do not wake up a writer until he can make "significant"
2790 	 * progress.  --DaveM
2791 	 */
2792 	if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2793 		wq = rcu_dereference(sk->sk_wq);
2794 		if (skwq_has_sleeper(wq))
2795 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
2796 						EPOLLWRNORM | EPOLLWRBAND);
2797 
2798 		/* Should agree with poll, otherwise some programs break */
2799 		if (sock_writeable(sk))
2800 			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2801 	}
2802 
2803 	rcu_read_unlock();
2804 }
2805 
2806 static void sock_def_destruct(struct sock *sk)
2807 {
2808 }
2809 
2810 void sk_send_sigurg(struct sock *sk)
2811 {
2812 	if (sk->sk_socket && sk->sk_socket->file)
2813 		if (send_sigurg(&sk->sk_socket->file->f_owner))
2814 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2815 }
2816 EXPORT_SYMBOL(sk_send_sigurg);
2817 
2818 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2819 		    unsigned long expires)
2820 {
2821 	if (!mod_timer(timer, expires))
2822 		sock_hold(sk);
2823 }
2824 EXPORT_SYMBOL(sk_reset_timer);
2825 
2826 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2827 {
2828 	if (del_timer(timer))
2829 		__sock_put(sk);
2830 }
2831 EXPORT_SYMBOL(sk_stop_timer);
2832 
2833 void sock_init_data(struct socket *sock, struct sock *sk)
2834 {
2835 	sk_init_common(sk);
2836 	sk->sk_send_head	=	NULL;
2837 
2838 	timer_setup(&sk->sk_timer, NULL, 0);
2839 
2840 	sk->sk_allocation	=	GFP_KERNEL;
2841 	sk->sk_rcvbuf		=	sysctl_rmem_default;
2842 	sk->sk_sndbuf		=	sysctl_wmem_default;
2843 	sk->sk_state		=	TCP_CLOSE;
2844 	sk_set_socket(sk, sock);
2845 
2846 	sock_set_flag(sk, SOCK_ZAPPED);
2847 
2848 	if (sock) {
2849 		sk->sk_type	=	sock->type;
2850 		RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
2851 		sock->sk	=	sk;
2852 		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
2853 	} else {
2854 		RCU_INIT_POINTER(sk->sk_wq, NULL);
2855 		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
2856 	}
2857 
2858 	rwlock_init(&sk->sk_callback_lock);
2859 	if (sk->sk_kern_sock)
2860 		lockdep_set_class_and_name(
2861 			&sk->sk_callback_lock,
2862 			af_kern_callback_keys + sk->sk_family,
2863 			af_family_kern_clock_key_strings[sk->sk_family]);
2864 	else
2865 		lockdep_set_class_and_name(
2866 			&sk->sk_callback_lock,
2867 			af_callback_keys + sk->sk_family,
2868 			af_family_clock_key_strings[sk->sk_family]);
2869 
2870 	sk->sk_state_change	=	sock_def_wakeup;
2871 	sk->sk_data_ready	=	sock_def_readable;
2872 	sk->sk_write_space	=	sock_def_write_space;
2873 	sk->sk_error_report	=	sock_def_error_report;
2874 	sk->sk_destruct		=	sock_def_destruct;
2875 
2876 	sk->sk_frag.page	=	NULL;
2877 	sk->sk_frag.offset	=	0;
2878 	sk->sk_peek_off		=	-1;
2879 
2880 	sk->sk_peer_pid 	=	NULL;
2881 	sk->sk_peer_cred	=	NULL;
2882 	sk->sk_write_pending	=	0;
2883 	sk->sk_rcvlowat		=	1;
2884 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2885 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2886 
2887 	sk->sk_stamp = SK_DEFAULT_STAMP;
2888 #if BITS_PER_LONG==32
2889 	seqlock_init(&sk->sk_stamp_seq);
2890 #endif
2891 	atomic_set(&sk->sk_zckey, 0);
2892 
2893 #ifdef CONFIG_NET_RX_BUSY_POLL
2894 	sk->sk_napi_id		=	0;
2895 	sk->sk_ll_usec		=	sysctl_net_busy_read;
2896 #endif
2897 
2898 	sk->sk_max_pacing_rate = ~0UL;
2899 	sk->sk_pacing_rate = ~0UL;
2900 	sk->sk_pacing_shift = 10;
2901 	sk->sk_incoming_cpu = -1;
2902 
2903 	sk_rx_queue_clear(sk);
2904 	/*
2905 	 * Before updating sk_refcnt, we must commit prior changes to memory
2906 	 * (Documentation/RCU/rculist_nulls.txt for details)
2907 	 */
2908 	smp_wmb();
2909 	refcount_set(&sk->sk_refcnt, 1);
2910 	atomic_set(&sk->sk_drops, 0);
2911 }
2912 EXPORT_SYMBOL(sock_init_data);
2913 
2914 void lock_sock_nested(struct sock *sk, int subclass)
2915 {
2916 	might_sleep();
2917 	spin_lock_bh(&sk->sk_lock.slock);
2918 	if (sk->sk_lock.owned)
2919 		__lock_sock(sk);
2920 	sk->sk_lock.owned = 1;
2921 	spin_unlock(&sk->sk_lock.slock);
2922 	/*
2923 	 * The sk_lock has mutex_lock() semantics here:
2924 	 */
2925 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2926 	local_bh_enable();
2927 }
2928 EXPORT_SYMBOL(lock_sock_nested);
2929 
2930 void release_sock(struct sock *sk)
2931 {
2932 	spin_lock_bh(&sk->sk_lock.slock);
2933 	if (sk->sk_backlog.tail)
2934 		__release_sock(sk);
2935 
2936 	/* Warning : release_cb() might need to release sk ownership,
2937 	 * ie call sock_release_ownership(sk) before us.
2938 	 */
2939 	if (sk->sk_prot->release_cb)
2940 		sk->sk_prot->release_cb(sk);
2941 
2942 	sock_release_ownership(sk);
2943 	if (waitqueue_active(&sk->sk_lock.wq))
2944 		wake_up(&sk->sk_lock.wq);
2945 	spin_unlock_bh(&sk->sk_lock.slock);
2946 }
2947 EXPORT_SYMBOL(release_sock);
2948 
2949 /**
2950  * lock_sock_fast - fast version of lock_sock
2951  * @sk: socket
2952  *
2953  * This version should be used for very small section, where process wont block
2954  * return false if fast path is taken:
2955  *
2956  *   sk_lock.slock locked, owned = 0, BH disabled
2957  *
2958  * return true if slow path is taken:
2959  *
2960  *   sk_lock.slock unlocked, owned = 1, BH enabled
2961  */
2962 bool lock_sock_fast(struct sock *sk)
2963 {
2964 	might_sleep();
2965 	spin_lock_bh(&sk->sk_lock.slock);
2966 
2967 	if (!sk->sk_lock.owned)
2968 		/*
2969 		 * Note : We must disable BH
2970 		 */
2971 		return false;
2972 
2973 	__lock_sock(sk);
2974 	sk->sk_lock.owned = 1;
2975 	spin_unlock(&sk->sk_lock.slock);
2976 	/*
2977 	 * The sk_lock has mutex_lock() semantics here:
2978 	 */
2979 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2980 	local_bh_enable();
2981 	return true;
2982 }
2983 EXPORT_SYMBOL(lock_sock_fast);
2984 
2985 int sock_gettstamp(struct socket *sock, void __user *userstamp,
2986 		   bool timeval, bool time32)
2987 {
2988 	struct sock *sk = sock->sk;
2989 	struct timespec64 ts;
2990 
2991 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2992 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
2993 	if (ts.tv_sec == -1)
2994 		return -ENOENT;
2995 	if (ts.tv_sec == 0) {
2996 		ktime_t kt = ktime_get_real();
2997 		sock_write_timestamp(sk, kt);;
2998 		ts = ktime_to_timespec64(kt);
2999 	}
3000 
3001 	if (timeval)
3002 		ts.tv_nsec /= 1000;
3003 
3004 #ifdef CONFIG_COMPAT_32BIT_TIME
3005 	if (time32)
3006 		return put_old_timespec32(&ts, userstamp);
3007 #endif
3008 #ifdef CONFIG_SPARC64
3009 	/* beware of padding in sparc64 timeval */
3010 	if (timeval && !in_compat_syscall()) {
3011 		struct __kernel_old_timeval __user tv = {
3012 			.tv_sec = ts.tv_sec,
3013 			.tv_usec = ts.tv_nsec,
3014 		};
3015 		if (copy_to_user(userstamp, &tv, sizeof(tv)))
3016 			return -EFAULT;
3017 		return 0;
3018 	}
3019 #endif
3020 	return put_timespec64(&ts, userstamp);
3021 }
3022 EXPORT_SYMBOL(sock_gettstamp);
3023 
3024 void sock_enable_timestamp(struct sock *sk, int flag)
3025 {
3026 	if (!sock_flag(sk, flag)) {
3027 		unsigned long previous_flags = sk->sk_flags;
3028 
3029 		sock_set_flag(sk, flag);
3030 		/*
3031 		 * we just set one of the two flags which require net
3032 		 * time stamping, but time stamping might have been on
3033 		 * already because of the other one
3034 		 */
3035 		if (sock_needs_netstamp(sk) &&
3036 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3037 			net_enable_timestamp();
3038 	}
3039 }
3040 
3041 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3042 		       int level, int type)
3043 {
3044 	struct sock_exterr_skb *serr;
3045 	struct sk_buff *skb;
3046 	int copied, err;
3047 
3048 	err = -EAGAIN;
3049 	skb = sock_dequeue_err_skb(sk);
3050 	if (skb == NULL)
3051 		goto out;
3052 
3053 	copied = skb->len;
3054 	if (copied > len) {
3055 		msg->msg_flags |= MSG_TRUNC;
3056 		copied = len;
3057 	}
3058 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3059 	if (err)
3060 		goto out_free_skb;
3061 
3062 	sock_recv_timestamp(msg, sk, skb);
3063 
3064 	serr = SKB_EXT_ERR(skb);
3065 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3066 
3067 	msg->msg_flags |= MSG_ERRQUEUE;
3068 	err = copied;
3069 
3070 out_free_skb:
3071 	kfree_skb(skb);
3072 out:
3073 	return err;
3074 }
3075 EXPORT_SYMBOL(sock_recv_errqueue);
3076 
3077 /*
3078  *	Get a socket option on an socket.
3079  *
3080  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3081  *	asynchronous errors should be reported by getsockopt. We assume
3082  *	this means if you specify SO_ERROR (otherwise whats the point of it).
3083  */
3084 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3085 			   char __user *optval, int __user *optlen)
3086 {
3087 	struct sock *sk = sock->sk;
3088 
3089 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3090 }
3091 EXPORT_SYMBOL(sock_common_getsockopt);
3092 
3093 #ifdef CONFIG_COMPAT
3094 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
3095 				  char __user *optval, int __user *optlen)
3096 {
3097 	struct sock *sk = sock->sk;
3098 
3099 	if (sk->sk_prot->compat_getsockopt != NULL)
3100 		return sk->sk_prot->compat_getsockopt(sk, level, optname,
3101 						      optval, optlen);
3102 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3103 }
3104 EXPORT_SYMBOL(compat_sock_common_getsockopt);
3105 #endif
3106 
3107 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3108 			int flags)
3109 {
3110 	struct sock *sk = sock->sk;
3111 	int addr_len = 0;
3112 	int err;
3113 
3114 	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
3115 				   flags & ~MSG_DONTWAIT, &addr_len);
3116 	if (err >= 0)
3117 		msg->msg_namelen = addr_len;
3118 	return err;
3119 }
3120 EXPORT_SYMBOL(sock_common_recvmsg);
3121 
3122 /*
3123  *	Set socket options on an inet socket.
3124  */
3125 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3126 			   char __user *optval, unsigned int optlen)
3127 {
3128 	struct sock *sk = sock->sk;
3129 
3130 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3131 }
3132 EXPORT_SYMBOL(sock_common_setsockopt);
3133 
3134 #ifdef CONFIG_COMPAT
3135 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
3136 				  char __user *optval, unsigned int optlen)
3137 {
3138 	struct sock *sk = sock->sk;
3139 
3140 	if (sk->sk_prot->compat_setsockopt != NULL)
3141 		return sk->sk_prot->compat_setsockopt(sk, level, optname,
3142 						      optval, optlen);
3143 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3144 }
3145 EXPORT_SYMBOL(compat_sock_common_setsockopt);
3146 #endif
3147 
3148 void sk_common_release(struct sock *sk)
3149 {
3150 	if (sk->sk_prot->destroy)
3151 		sk->sk_prot->destroy(sk);
3152 
3153 	/*
3154 	 * Observation: when sock_common_release is called, processes have
3155 	 * no access to socket. But net still has.
3156 	 * Step one, detach it from networking:
3157 	 *
3158 	 * A. Remove from hash tables.
3159 	 */
3160 
3161 	sk->sk_prot->unhash(sk);
3162 
3163 	/*
3164 	 * In this point socket cannot receive new packets, but it is possible
3165 	 * that some packets are in flight because some CPU runs receiver and
3166 	 * did hash table lookup before we unhashed socket. They will achieve
3167 	 * receive queue and will be purged by socket destructor.
3168 	 *
3169 	 * Also we still have packets pending on receive queue and probably,
3170 	 * our own packets waiting in device queues. sock_destroy will drain
3171 	 * receive queue, but transmitted packets will delay socket destruction
3172 	 * until the last reference will be released.
3173 	 */
3174 
3175 	sock_orphan(sk);
3176 
3177 	xfrm_sk_free_policy(sk);
3178 
3179 	sk_refcnt_debug_release(sk);
3180 
3181 	sock_put(sk);
3182 }
3183 EXPORT_SYMBOL(sk_common_release);
3184 
3185 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3186 {
3187 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3188 
3189 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3190 	mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
3191 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3192 	mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
3193 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3194 	mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
3195 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3196 	mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len;
3197 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3198 }
3199 
3200 #ifdef CONFIG_PROC_FS
3201 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
3202 struct prot_inuse {
3203 	int val[PROTO_INUSE_NR];
3204 };
3205 
3206 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3207 
3208 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3209 {
3210 	__this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
3211 }
3212 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3213 
3214 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3215 {
3216 	int cpu, idx = prot->inuse_idx;
3217 	int res = 0;
3218 
3219 	for_each_possible_cpu(cpu)
3220 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3221 
3222 	return res >= 0 ? res : 0;
3223 }
3224 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3225 
3226 static void sock_inuse_add(struct net *net, int val)
3227 {
3228 	this_cpu_add(*net->core.sock_inuse, val);
3229 }
3230 
3231 int sock_inuse_get(struct net *net)
3232 {
3233 	int cpu, res = 0;
3234 
3235 	for_each_possible_cpu(cpu)
3236 		res += *per_cpu_ptr(net->core.sock_inuse, cpu);
3237 
3238 	return res;
3239 }
3240 
3241 EXPORT_SYMBOL_GPL(sock_inuse_get);
3242 
3243 static int __net_init sock_inuse_init_net(struct net *net)
3244 {
3245 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3246 	if (net->core.prot_inuse == NULL)
3247 		return -ENOMEM;
3248 
3249 	net->core.sock_inuse = alloc_percpu(int);
3250 	if (net->core.sock_inuse == NULL)
3251 		goto out;
3252 
3253 	return 0;
3254 
3255 out:
3256 	free_percpu(net->core.prot_inuse);
3257 	return -ENOMEM;
3258 }
3259 
3260 static void __net_exit sock_inuse_exit_net(struct net *net)
3261 {
3262 	free_percpu(net->core.prot_inuse);
3263 	free_percpu(net->core.sock_inuse);
3264 }
3265 
3266 static struct pernet_operations net_inuse_ops = {
3267 	.init = sock_inuse_init_net,
3268 	.exit = sock_inuse_exit_net,
3269 };
3270 
3271 static __init int net_inuse_init(void)
3272 {
3273 	if (register_pernet_subsys(&net_inuse_ops))
3274 		panic("Cannot initialize net inuse counters");
3275 
3276 	return 0;
3277 }
3278 
3279 core_initcall(net_inuse_init);
3280 
3281 static void assign_proto_idx(struct proto *prot)
3282 {
3283 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3284 
3285 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3286 		pr_err("PROTO_INUSE_NR exhausted\n");
3287 		return;
3288 	}
3289 
3290 	set_bit(prot->inuse_idx, proto_inuse_idx);
3291 }
3292 
3293 static void release_proto_idx(struct proto *prot)
3294 {
3295 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3296 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3297 }
3298 #else
3299 static inline void assign_proto_idx(struct proto *prot)
3300 {
3301 }
3302 
3303 static inline void release_proto_idx(struct proto *prot)
3304 {
3305 }
3306 
3307 static void sock_inuse_add(struct net *net, int val)
3308 {
3309 }
3310 #endif
3311 
3312 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3313 {
3314 	if (!rsk_prot)
3315 		return;
3316 	kfree(rsk_prot->slab_name);
3317 	rsk_prot->slab_name = NULL;
3318 	kmem_cache_destroy(rsk_prot->slab);
3319 	rsk_prot->slab = NULL;
3320 }
3321 
3322 static int req_prot_init(const struct proto *prot)
3323 {
3324 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3325 
3326 	if (!rsk_prot)
3327 		return 0;
3328 
3329 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3330 					prot->name);
3331 	if (!rsk_prot->slab_name)
3332 		return -ENOMEM;
3333 
3334 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3335 					   rsk_prot->obj_size, 0,
3336 					   SLAB_ACCOUNT | prot->slab_flags,
3337 					   NULL);
3338 
3339 	if (!rsk_prot->slab) {
3340 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3341 			prot->name);
3342 		return -ENOMEM;
3343 	}
3344 	return 0;
3345 }
3346 
3347 int proto_register(struct proto *prot, int alloc_slab)
3348 {
3349 	if (alloc_slab) {
3350 		prot->slab = kmem_cache_create_usercopy(prot->name,
3351 					prot->obj_size, 0,
3352 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3353 					prot->slab_flags,
3354 					prot->useroffset, prot->usersize,
3355 					NULL);
3356 
3357 		if (prot->slab == NULL) {
3358 			pr_crit("%s: Can't create sock SLAB cache!\n",
3359 				prot->name);
3360 			goto out;
3361 		}
3362 
3363 		if (req_prot_init(prot))
3364 			goto out_free_request_sock_slab;
3365 
3366 		if (prot->twsk_prot != NULL) {
3367 			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
3368 
3369 			if (prot->twsk_prot->twsk_slab_name == NULL)
3370 				goto out_free_request_sock_slab;
3371 
3372 			prot->twsk_prot->twsk_slab =
3373 				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
3374 						  prot->twsk_prot->twsk_obj_size,
3375 						  0,
3376 						  SLAB_ACCOUNT |
3377 						  prot->slab_flags,
3378 						  NULL);
3379 			if (prot->twsk_prot->twsk_slab == NULL)
3380 				goto out_free_timewait_sock_slab_name;
3381 		}
3382 	}
3383 
3384 	mutex_lock(&proto_list_mutex);
3385 	list_add(&prot->node, &proto_list);
3386 	assign_proto_idx(prot);
3387 	mutex_unlock(&proto_list_mutex);
3388 	return 0;
3389 
3390 out_free_timewait_sock_slab_name:
3391 	kfree(prot->twsk_prot->twsk_slab_name);
3392 out_free_request_sock_slab:
3393 	req_prot_cleanup(prot->rsk_prot);
3394 
3395 	kmem_cache_destroy(prot->slab);
3396 	prot->slab = NULL;
3397 out:
3398 	return -ENOBUFS;
3399 }
3400 EXPORT_SYMBOL(proto_register);
3401 
3402 void proto_unregister(struct proto *prot)
3403 {
3404 	mutex_lock(&proto_list_mutex);
3405 	release_proto_idx(prot);
3406 	list_del(&prot->node);
3407 	mutex_unlock(&proto_list_mutex);
3408 
3409 	kmem_cache_destroy(prot->slab);
3410 	prot->slab = NULL;
3411 
3412 	req_prot_cleanup(prot->rsk_prot);
3413 
3414 	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
3415 		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
3416 		kfree(prot->twsk_prot->twsk_slab_name);
3417 		prot->twsk_prot->twsk_slab = NULL;
3418 	}
3419 }
3420 EXPORT_SYMBOL(proto_unregister);
3421 
3422 int sock_load_diag_module(int family, int protocol)
3423 {
3424 	if (!protocol) {
3425 		if (!sock_is_registered(family))
3426 			return -ENOENT;
3427 
3428 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3429 				      NETLINK_SOCK_DIAG, family);
3430 	}
3431 
3432 #ifdef CONFIG_INET
3433 	if (family == AF_INET &&
3434 	    protocol != IPPROTO_RAW &&
3435 	    !rcu_access_pointer(inet_protos[protocol]))
3436 		return -ENOENT;
3437 #endif
3438 
3439 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3440 			      NETLINK_SOCK_DIAG, family, protocol);
3441 }
3442 EXPORT_SYMBOL(sock_load_diag_module);
3443 
3444 #ifdef CONFIG_PROC_FS
3445 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3446 	__acquires(proto_list_mutex)
3447 {
3448 	mutex_lock(&proto_list_mutex);
3449 	return seq_list_start_head(&proto_list, *pos);
3450 }
3451 
3452 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3453 {
3454 	return seq_list_next(v, &proto_list, pos);
3455 }
3456 
3457 static void proto_seq_stop(struct seq_file *seq, void *v)
3458 	__releases(proto_list_mutex)
3459 {
3460 	mutex_unlock(&proto_list_mutex);
3461 }
3462 
3463 static char proto_method_implemented(const void *method)
3464 {
3465 	return method == NULL ? 'n' : 'y';
3466 }
3467 static long sock_prot_memory_allocated(struct proto *proto)
3468 {
3469 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3470 }
3471 
3472 static char *sock_prot_memory_pressure(struct proto *proto)
3473 {
3474 	return proto->memory_pressure != NULL ?
3475 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3476 }
3477 
3478 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3479 {
3480 
3481 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
3482 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3483 		   proto->name,
3484 		   proto->obj_size,
3485 		   sock_prot_inuse_get(seq_file_net(seq), proto),
3486 		   sock_prot_memory_allocated(proto),
3487 		   sock_prot_memory_pressure(proto),
3488 		   proto->max_header,
3489 		   proto->slab == NULL ? "no" : "yes",
3490 		   module_name(proto->owner),
3491 		   proto_method_implemented(proto->close),
3492 		   proto_method_implemented(proto->connect),
3493 		   proto_method_implemented(proto->disconnect),
3494 		   proto_method_implemented(proto->accept),
3495 		   proto_method_implemented(proto->ioctl),
3496 		   proto_method_implemented(proto->init),
3497 		   proto_method_implemented(proto->destroy),
3498 		   proto_method_implemented(proto->shutdown),
3499 		   proto_method_implemented(proto->setsockopt),
3500 		   proto_method_implemented(proto->getsockopt),
3501 		   proto_method_implemented(proto->sendmsg),
3502 		   proto_method_implemented(proto->recvmsg),
3503 		   proto_method_implemented(proto->sendpage),
3504 		   proto_method_implemented(proto->bind),
3505 		   proto_method_implemented(proto->backlog_rcv),
3506 		   proto_method_implemented(proto->hash),
3507 		   proto_method_implemented(proto->unhash),
3508 		   proto_method_implemented(proto->get_port),
3509 		   proto_method_implemented(proto->enter_memory_pressure));
3510 }
3511 
3512 static int proto_seq_show(struct seq_file *seq, void *v)
3513 {
3514 	if (v == &proto_list)
3515 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3516 			   "protocol",
3517 			   "size",
3518 			   "sockets",
3519 			   "memory",
3520 			   "press",
3521 			   "maxhdr",
3522 			   "slab",
3523 			   "module",
3524 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3525 	else
3526 		proto_seq_printf(seq, list_entry(v, struct proto, node));
3527 	return 0;
3528 }
3529 
3530 static const struct seq_operations proto_seq_ops = {
3531 	.start  = proto_seq_start,
3532 	.next   = proto_seq_next,
3533 	.stop   = proto_seq_stop,
3534 	.show   = proto_seq_show,
3535 };
3536 
3537 static __net_init int proto_init_net(struct net *net)
3538 {
3539 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
3540 			sizeof(struct seq_net_private)))
3541 		return -ENOMEM;
3542 
3543 	return 0;
3544 }
3545 
3546 static __net_exit void proto_exit_net(struct net *net)
3547 {
3548 	remove_proc_entry("protocols", net->proc_net);
3549 }
3550 
3551 
3552 static __net_initdata struct pernet_operations proto_net_ops = {
3553 	.init = proto_init_net,
3554 	.exit = proto_exit_net,
3555 };
3556 
3557 static int __init proto_init(void)
3558 {
3559 	return register_pernet_subsys(&proto_net_ops);
3560 }
3561 
3562 subsys_initcall(proto_init);
3563 
3564 #endif /* PROC_FS */
3565 
3566 #ifdef CONFIG_NET_RX_BUSY_POLL
3567 bool sk_busy_loop_end(void *p, unsigned long start_time)
3568 {
3569 	struct sock *sk = p;
3570 
3571 	return !skb_queue_empty(&sk->sk_receive_queue) ||
3572 	       sk_busy_loop_timeout(sk, start_time);
3573 }
3574 EXPORT_SYMBOL(sk_busy_loop_end);
3575 #endif /* CONFIG_NET_RX_BUSY_POLL */
3576