xref: /openbmc/linux/net/core/sock.c (revision 3557b3fd)
1 /*
2  * INET		An implementation of the TCP/IP protocol suite for the LINUX
3  *		operating system.  INET is implemented using the  BSD Socket
4  *		interface as the means of communication with the user level.
5  *
6  *		Generic socket support routines. Memory allocators, socket lock/release
7  *		handler for protocols to use and generic option handler.
8  *
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  *		This program is free software; you can redistribute it and/or
87  *		modify it under the terms of the GNU General Public License
88  *		as published by the Free Software Foundation; either version
89  *		2 of the License, or (at your option) any later version.
90  */
91 
92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
93 
94 #include <asm/unaligned.h>
95 #include <linux/capability.h>
96 #include <linux/errno.h>
97 #include <linux/errqueue.h>
98 #include <linux/types.h>
99 #include <linux/socket.h>
100 #include <linux/in.h>
101 #include <linux/kernel.h>
102 #include <linux/module.h>
103 #include <linux/proc_fs.h>
104 #include <linux/seq_file.h>
105 #include <linux/sched.h>
106 #include <linux/sched/mm.h>
107 #include <linux/timer.h>
108 #include <linux/string.h>
109 #include <linux/sockios.h>
110 #include <linux/net.h>
111 #include <linux/mm.h>
112 #include <linux/slab.h>
113 #include <linux/interrupt.h>
114 #include <linux/poll.h>
115 #include <linux/tcp.h>
116 #include <linux/init.h>
117 #include <linux/highmem.h>
118 #include <linux/user_namespace.h>
119 #include <linux/static_key.h>
120 #include <linux/memcontrol.h>
121 #include <linux/prefetch.h>
122 
123 #include <linux/uaccess.h>
124 
125 #include <linux/netdevice.h>
126 #include <net/protocol.h>
127 #include <linux/skbuff.h>
128 #include <net/net_namespace.h>
129 #include <net/request_sock.h>
130 #include <net/sock.h>
131 #include <linux/net_tstamp.h>
132 #include <net/xfrm.h>
133 #include <linux/ipsec.h>
134 #include <net/cls_cgroup.h>
135 #include <net/netprio_cgroup.h>
136 #include <linux/sock_diag.h>
137 
138 #include <linux/filter.h>
139 #include <net/sock_reuseport.h>
140 
141 #include <trace/events/sock.h>
142 
143 #include <net/tcp.h>
144 #include <net/busy_poll.h>
145 
146 static DEFINE_MUTEX(proto_list_mutex);
147 static LIST_HEAD(proto_list);
148 
149 static void sock_inuse_add(struct net *net, int val);
150 
151 /**
152  * sk_ns_capable - General socket capability test
153  * @sk: Socket to use a capability on or through
154  * @user_ns: The user namespace of the capability to use
155  * @cap: The capability to use
156  *
157  * Test to see if the opener of the socket had when the socket was
158  * created and the current process has the capability @cap in the user
159  * namespace @user_ns.
160  */
161 bool sk_ns_capable(const struct sock *sk,
162 		   struct user_namespace *user_ns, int cap)
163 {
164 	return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
165 		ns_capable(user_ns, cap);
166 }
167 EXPORT_SYMBOL(sk_ns_capable);
168 
169 /**
170  * sk_capable - Socket global capability test
171  * @sk: Socket to use a capability on or through
172  * @cap: The global capability to use
173  *
174  * Test to see if the opener of the socket had when the socket was
175  * created and the current process has the capability @cap in all user
176  * namespaces.
177  */
178 bool sk_capable(const struct sock *sk, int cap)
179 {
180 	return sk_ns_capable(sk, &init_user_ns, cap);
181 }
182 EXPORT_SYMBOL(sk_capable);
183 
184 /**
185  * sk_net_capable - Network namespace socket capability test
186  * @sk: Socket to use a capability on or through
187  * @cap: The capability to use
188  *
189  * Test to see if the opener of the socket had when the socket was created
190  * and the current process has the capability @cap over the network namespace
191  * the socket is a member of.
192  */
193 bool sk_net_capable(const struct sock *sk, int cap)
194 {
195 	return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
196 }
197 EXPORT_SYMBOL(sk_net_capable);
198 
199 /*
200  * Each address family might have different locking rules, so we have
201  * one slock key per address family and separate keys for internal and
202  * userspace sockets.
203  */
204 static struct lock_class_key af_family_keys[AF_MAX];
205 static struct lock_class_key af_family_kern_keys[AF_MAX];
206 static struct lock_class_key af_family_slock_keys[AF_MAX];
207 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
208 
209 /*
210  * Make lock validator output more readable. (we pre-construct these
211  * strings build-time, so that runtime initialization of socket
212  * locks is fast):
213  */
214 
215 #define _sock_locks(x)						  \
216   x "AF_UNSPEC",	x "AF_UNIX"     ,	x "AF_INET"     , \
217   x "AF_AX25"  ,	x "AF_IPX"      ,	x "AF_APPLETALK", \
218   x "AF_NETROM",	x "AF_BRIDGE"   ,	x "AF_ATMPVC"   , \
219   x "AF_X25"   ,	x "AF_INET6"    ,	x "AF_ROSE"     , \
220   x "AF_DECnet",	x "AF_NETBEUI"  ,	x "AF_SECURITY" , \
221   x "AF_KEY"   ,	x "AF_NETLINK"  ,	x "AF_PACKET"   , \
222   x "AF_ASH"   ,	x "AF_ECONET"   ,	x "AF_ATMSVC"   , \
223   x "AF_RDS"   ,	x "AF_SNA"      ,	x "AF_IRDA"     , \
224   x "AF_PPPOX" ,	x "AF_WANPIPE"  ,	x "AF_LLC"      , \
225   x "27"       ,	x "28"          ,	x "AF_CAN"      , \
226   x "AF_TIPC"  ,	x "AF_BLUETOOTH",	x "IUCV"        , \
227   x "AF_RXRPC" ,	x "AF_ISDN"     ,	x "AF_PHONET"   , \
228   x "AF_IEEE802154",	x "AF_CAIF"	,	x "AF_ALG"      , \
229   x "AF_NFC"   ,	x "AF_VSOCK"    ,	x "AF_KCM"      , \
230   x "AF_QIPCRTR",	x "AF_SMC"	,	x "AF_XDP"	, \
231   x "AF_MAX"
232 
233 static const char *const af_family_key_strings[AF_MAX+1] = {
234 	_sock_locks("sk_lock-")
235 };
236 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
237 	_sock_locks("slock-")
238 };
239 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
240 	_sock_locks("clock-")
241 };
242 
243 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
244 	_sock_locks("k-sk_lock-")
245 };
246 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
247 	_sock_locks("k-slock-")
248 };
249 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
250 	_sock_locks("k-clock-")
251 };
252 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
253 	_sock_locks("rlock-")
254 };
255 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
256 	_sock_locks("wlock-")
257 };
258 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
259 	_sock_locks("elock-")
260 };
261 
262 /*
263  * sk_callback_lock and sk queues locking rules are per-address-family,
264  * so split the lock classes by using a per-AF key:
265  */
266 static struct lock_class_key af_callback_keys[AF_MAX];
267 static struct lock_class_key af_rlock_keys[AF_MAX];
268 static struct lock_class_key af_wlock_keys[AF_MAX];
269 static struct lock_class_key af_elock_keys[AF_MAX];
270 static struct lock_class_key af_kern_callback_keys[AF_MAX];
271 
272 /* Run time adjustable parameters. */
273 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
274 EXPORT_SYMBOL(sysctl_wmem_max);
275 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
276 EXPORT_SYMBOL(sysctl_rmem_max);
277 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
278 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
279 
280 /* Maximal space eaten by iovec or ancillary data plus some space */
281 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
282 EXPORT_SYMBOL(sysctl_optmem_max);
283 
284 int sysctl_tstamp_allow_data __read_mostly = 1;
285 
286 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
287 EXPORT_SYMBOL_GPL(memalloc_socks_key);
288 
289 /**
290  * sk_set_memalloc - sets %SOCK_MEMALLOC
291  * @sk: socket to set it on
292  *
293  * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
294  * It's the responsibility of the admin to adjust min_free_kbytes
295  * to meet the requirements
296  */
297 void sk_set_memalloc(struct sock *sk)
298 {
299 	sock_set_flag(sk, SOCK_MEMALLOC);
300 	sk->sk_allocation |= __GFP_MEMALLOC;
301 	static_branch_inc(&memalloc_socks_key);
302 }
303 EXPORT_SYMBOL_GPL(sk_set_memalloc);
304 
305 void sk_clear_memalloc(struct sock *sk)
306 {
307 	sock_reset_flag(sk, SOCK_MEMALLOC);
308 	sk->sk_allocation &= ~__GFP_MEMALLOC;
309 	static_branch_dec(&memalloc_socks_key);
310 
311 	/*
312 	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
313 	 * progress of swapping. SOCK_MEMALLOC may be cleared while
314 	 * it has rmem allocations due to the last swapfile being deactivated
315 	 * but there is a risk that the socket is unusable due to exceeding
316 	 * the rmem limits. Reclaim the reserves and obey rmem limits again.
317 	 */
318 	sk_mem_reclaim(sk);
319 }
320 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
321 
322 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
323 {
324 	int ret;
325 	unsigned int noreclaim_flag;
326 
327 	/* these should have been dropped before queueing */
328 	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
329 
330 	noreclaim_flag = memalloc_noreclaim_save();
331 	ret = sk->sk_backlog_rcv(sk, skb);
332 	memalloc_noreclaim_restore(noreclaim_flag);
333 
334 	return ret;
335 }
336 EXPORT_SYMBOL(__sk_backlog_rcv);
337 
338 static int sock_get_timeout(long timeo, void *optval, bool old_timeval)
339 {
340 	struct __kernel_sock_timeval tv;
341 	int size;
342 
343 	if (timeo == MAX_SCHEDULE_TIMEOUT) {
344 		tv.tv_sec = 0;
345 		tv.tv_usec = 0;
346 	} else {
347 		tv.tv_sec = timeo / HZ;
348 		tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
349 	}
350 
351 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
352 		struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
353 		*(struct old_timeval32 *)optval = tv32;
354 		return sizeof(tv32);
355 	}
356 
357 	if (old_timeval) {
358 		struct __kernel_old_timeval old_tv;
359 		old_tv.tv_sec = tv.tv_sec;
360 		old_tv.tv_usec = tv.tv_usec;
361 		*(struct __kernel_old_timeval *)optval = old_tv;
362 		size = sizeof(old_tv);
363 	} else {
364 		*(struct __kernel_sock_timeval *)optval = tv;
365 		size = sizeof(tv);
366 	}
367 
368 	return size;
369 }
370 
371 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen, bool old_timeval)
372 {
373 	struct __kernel_sock_timeval tv;
374 
375 	if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
376 		struct old_timeval32 tv32;
377 
378 		if (optlen < sizeof(tv32))
379 			return -EINVAL;
380 
381 		if (copy_from_user(&tv32, optval, sizeof(tv32)))
382 			return -EFAULT;
383 		tv.tv_sec = tv32.tv_sec;
384 		tv.tv_usec = tv32.tv_usec;
385 	} else if (old_timeval) {
386 		struct __kernel_old_timeval old_tv;
387 
388 		if (optlen < sizeof(old_tv))
389 			return -EINVAL;
390 		if (copy_from_user(&old_tv, optval, sizeof(old_tv)))
391 			return -EFAULT;
392 		tv.tv_sec = old_tv.tv_sec;
393 		tv.tv_usec = old_tv.tv_usec;
394 	} else {
395 		if (optlen < sizeof(tv))
396 			return -EINVAL;
397 		if (copy_from_user(&tv, optval, sizeof(tv)))
398 			return -EFAULT;
399 	}
400 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
401 		return -EDOM;
402 
403 	if (tv.tv_sec < 0) {
404 		static int warned __read_mostly;
405 
406 		*timeo_p = 0;
407 		if (warned < 10 && net_ratelimit()) {
408 			warned++;
409 			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
410 				__func__, current->comm, task_pid_nr(current));
411 		}
412 		return 0;
413 	}
414 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
415 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
416 		return 0;
417 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
418 		*timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
419 	return 0;
420 }
421 
422 static void sock_warn_obsolete_bsdism(const char *name)
423 {
424 	static int warned;
425 	static char warncomm[TASK_COMM_LEN];
426 	if (strcmp(warncomm, current->comm) && warned < 5) {
427 		strcpy(warncomm,  current->comm);
428 		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
429 			warncomm, name);
430 		warned++;
431 	}
432 }
433 
434 static bool sock_needs_netstamp(const struct sock *sk)
435 {
436 	switch (sk->sk_family) {
437 	case AF_UNSPEC:
438 	case AF_UNIX:
439 		return false;
440 	default:
441 		return true;
442 	}
443 }
444 
445 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
446 {
447 	if (sk->sk_flags & flags) {
448 		sk->sk_flags &= ~flags;
449 		if (sock_needs_netstamp(sk) &&
450 		    !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
451 			net_disable_timestamp();
452 	}
453 }
454 
455 
456 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
457 {
458 	unsigned long flags;
459 	struct sk_buff_head *list = &sk->sk_receive_queue;
460 
461 	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
462 		atomic_inc(&sk->sk_drops);
463 		trace_sock_rcvqueue_full(sk, skb);
464 		return -ENOMEM;
465 	}
466 
467 	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
468 		atomic_inc(&sk->sk_drops);
469 		return -ENOBUFS;
470 	}
471 
472 	skb->dev = NULL;
473 	skb_set_owner_r(skb, sk);
474 
475 	/* we escape from rcu protected region, make sure we dont leak
476 	 * a norefcounted dst
477 	 */
478 	skb_dst_force(skb);
479 
480 	spin_lock_irqsave(&list->lock, flags);
481 	sock_skb_set_dropcount(sk, skb);
482 	__skb_queue_tail(list, skb);
483 	spin_unlock_irqrestore(&list->lock, flags);
484 
485 	if (!sock_flag(sk, SOCK_DEAD))
486 		sk->sk_data_ready(sk);
487 	return 0;
488 }
489 EXPORT_SYMBOL(__sock_queue_rcv_skb);
490 
491 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
492 {
493 	int err;
494 
495 	err = sk_filter(sk, skb);
496 	if (err)
497 		return err;
498 
499 	return __sock_queue_rcv_skb(sk, skb);
500 }
501 EXPORT_SYMBOL(sock_queue_rcv_skb);
502 
503 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
504 		     const int nested, unsigned int trim_cap, bool refcounted)
505 {
506 	int rc = NET_RX_SUCCESS;
507 
508 	if (sk_filter_trim_cap(sk, skb, trim_cap))
509 		goto discard_and_relse;
510 
511 	skb->dev = NULL;
512 
513 	if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
514 		atomic_inc(&sk->sk_drops);
515 		goto discard_and_relse;
516 	}
517 	if (nested)
518 		bh_lock_sock_nested(sk);
519 	else
520 		bh_lock_sock(sk);
521 	if (!sock_owned_by_user(sk)) {
522 		/*
523 		 * trylock + unlock semantics:
524 		 */
525 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
526 
527 		rc = sk_backlog_rcv(sk, skb);
528 
529 		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
530 	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
531 		bh_unlock_sock(sk);
532 		atomic_inc(&sk->sk_drops);
533 		goto discard_and_relse;
534 	}
535 
536 	bh_unlock_sock(sk);
537 out:
538 	if (refcounted)
539 		sock_put(sk);
540 	return rc;
541 discard_and_relse:
542 	kfree_skb(skb);
543 	goto out;
544 }
545 EXPORT_SYMBOL(__sk_receive_skb);
546 
547 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
548 {
549 	struct dst_entry *dst = __sk_dst_get(sk);
550 
551 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
552 		sk_tx_queue_clear(sk);
553 		sk->sk_dst_pending_confirm = 0;
554 		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
555 		dst_release(dst);
556 		return NULL;
557 	}
558 
559 	return dst;
560 }
561 EXPORT_SYMBOL(__sk_dst_check);
562 
563 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
564 {
565 	struct dst_entry *dst = sk_dst_get(sk);
566 
567 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
568 		sk_dst_reset(sk);
569 		dst_release(dst);
570 		return NULL;
571 	}
572 
573 	return dst;
574 }
575 EXPORT_SYMBOL(sk_dst_check);
576 
577 static int sock_setbindtodevice_locked(struct sock *sk, int ifindex)
578 {
579 	int ret = -ENOPROTOOPT;
580 #ifdef CONFIG_NETDEVICES
581 	struct net *net = sock_net(sk);
582 
583 	/* Sorry... */
584 	ret = -EPERM;
585 	if (!ns_capable(net->user_ns, CAP_NET_RAW))
586 		goto out;
587 
588 	ret = -EINVAL;
589 	if (ifindex < 0)
590 		goto out;
591 
592 	sk->sk_bound_dev_if = ifindex;
593 	if (sk->sk_prot->rehash)
594 		sk->sk_prot->rehash(sk);
595 	sk_dst_reset(sk);
596 
597 	ret = 0;
598 
599 out:
600 #endif
601 
602 	return ret;
603 }
604 
605 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
606 				int optlen)
607 {
608 	int ret = -ENOPROTOOPT;
609 #ifdef CONFIG_NETDEVICES
610 	struct net *net = sock_net(sk);
611 	char devname[IFNAMSIZ];
612 	int index;
613 
614 	ret = -EINVAL;
615 	if (optlen < 0)
616 		goto out;
617 
618 	/* Bind this socket to a particular device like "eth0",
619 	 * as specified in the passed interface name. If the
620 	 * name is "" or the option length is zero the socket
621 	 * is not bound.
622 	 */
623 	if (optlen > IFNAMSIZ - 1)
624 		optlen = IFNAMSIZ - 1;
625 	memset(devname, 0, sizeof(devname));
626 
627 	ret = -EFAULT;
628 	if (copy_from_user(devname, optval, optlen))
629 		goto out;
630 
631 	index = 0;
632 	if (devname[0] != '\0') {
633 		struct net_device *dev;
634 
635 		rcu_read_lock();
636 		dev = dev_get_by_name_rcu(net, devname);
637 		if (dev)
638 			index = dev->ifindex;
639 		rcu_read_unlock();
640 		ret = -ENODEV;
641 		if (!dev)
642 			goto out;
643 	}
644 
645 	lock_sock(sk);
646 	ret = sock_setbindtodevice_locked(sk, index);
647 	release_sock(sk);
648 
649 out:
650 #endif
651 
652 	return ret;
653 }
654 
655 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
656 				int __user *optlen, int len)
657 {
658 	int ret = -ENOPROTOOPT;
659 #ifdef CONFIG_NETDEVICES
660 	struct net *net = sock_net(sk);
661 	char devname[IFNAMSIZ];
662 
663 	if (sk->sk_bound_dev_if == 0) {
664 		len = 0;
665 		goto zero;
666 	}
667 
668 	ret = -EINVAL;
669 	if (len < IFNAMSIZ)
670 		goto out;
671 
672 	ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
673 	if (ret)
674 		goto out;
675 
676 	len = strlen(devname) + 1;
677 
678 	ret = -EFAULT;
679 	if (copy_to_user(optval, devname, len))
680 		goto out;
681 
682 zero:
683 	ret = -EFAULT;
684 	if (put_user(len, optlen))
685 		goto out;
686 
687 	ret = 0;
688 
689 out:
690 #endif
691 
692 	return ret;
693 }
694 
695 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
696 {
697 	if (valbool)
698 		sock_set_flag(sk, bit);
699 	else
700 		sock_reset_flag(sk, bit);
701 }
702 
703 bool sk_mc_loop(struct sock *sk)
704 {
705 	if (dev_recursion_level())
706 		return false;
707 	if (!sk)
708 		return true;
709 	switch (sk->sk_family) {
710 	case AF_INET:
711 		return inet_sk(sk)->mc_loop;
712 #if IS_ENABLED(CONFIG_IPV6)
713 	case AF_INET6:
714 		return inet6_sk(sk)->mc_loop;
715 #endif
716 	}
717 	WARN_ON(1);
718 	return true;
719 }
720 EXPORT_SYMBOL(sk_mc_loop);
721 
722 /*
723  *	This is meant for all protocols to use and covers goings on
724  *	at the socket level. Everything here is generic.
725  */
726 
727 int sock_setsockopt(struct socket *sock, int level, int optname,
728 		    char __user *optval, unsigned int optlen)
729 {
730 	struct sock_txtime sk_txtime;
731 	struct sock *sk = sock->sk;
732 	int val;
733 	int valbool;
734 	struct linger ling;
735 	int ret = 0;
736 
737 	/*
738 	 *	Options without arguments
739 	 */
740 
741 	if (optname == SO_BINDTODEVICE)
742 		return sock_setbindtodevice(sk, optval, optlen);
743 
744 	if (optlen < sizeof(int))
745 		return -EINVAL;
746 
747 	if (get_user(val, (int __user *)optval))
748 		return -EFAULT;
749 
750 	valbool = val ? 1 : 0;
751 
752 	lock_sock(sk);
753 
754 	switch (optname) {
755 	case SO_DEBUG:
756 		if (val && !capable(CAP_NET_ADMIN))
757 			ret = -EACCES;
758 		else
759 			sock_valbool_flag(sk, SOCK_DBG, valbool);
760 		break;
761 	case SO_REUSEADDR:
762 		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
763 		break;
764 	case SO_REUSEPORT:
765 		sk->sk_reuseport = valbool;
766 		break;
767 	case SO_TYPE:
768 	case SO_PROTOCOL:
769 	case SO_DOMAIN:
770 	case SO_ERROR:
771 		ret = -ENOPROTOOPT;
772 		break;
773 	case SO_DONTROUTE:
774 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
775 		sk_dst_reset(sk);
776 		break;
777 	case SO_BROADCAST:
778 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
779 		break;
780 	case SO_SNDBUF:
781 		/* Don't error on this BSD doesn't and if you think
782 		 * about it this is right. Otherwise apps have to
783 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
784 		 * are treated in BSD as hints
785 		 */
786 		val = min_t(u32, val, sysctl_wmem_max);
787 set_sndbuf:
788 		/* Ensure val * 2 fits into an int, to prevent max_t()
789 		 * from treating it as a negative value.
790 		 */
791 		val = min_t(int, val, INT_MAX / 2);
792 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
793 		sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
794 		/* Wake up sending tasks if we upped the value. */
795 		sk->sk_write_space(sk);
796 		break;
797 
798 	case SO_SNDBUFFORCE:
799 		if (!capable(CAP_NET_ADMIN)) {
800 			ret = -EPERM;
801 			break;
802 		}
803 
804 		/* No negative values (to prevent underflow, as val will be
805 		 * multiplied by 2).
806 		 */
807 		if (val < 0)
808 			val = 0;
809 		goto set_sndbuf;
810 
811 	case SO_RCVBUF:
812 		/* Don't error on this BSD doesn't and if you think
813 		 * about it this is right. Otherwise apps have to
814 		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
815 		 * are treated in BSD as hints
816 		 */
817 		val = min_t(u32, val, sysctl_rmem_max);
818 set_rcvbuf:
819 		/* Ensure val * 2 fits into an int, to prevent max_t()
820 		 * from treating it as a negative value.
821 		 */
822 		val = min_t(int, val, INT_MAX / 2);
823 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
824 		/*
825 		 * We double it on the way in to account for
826 		 * "struct sk_buff" etc. overhead.   Applications
827 		 * assume that the SO_RCVBUF setting they make will
828 		 * allow that much actual data to be received on that
829 		 * socket.
830 		 *
831 		 * Applications are unaware that "struct sk_buff" and
832 		 * other overheads allocate from the receive buffer
833 		 * during socket buffer allocation.
834 		 *
835 		 * And after considering the possible alternatives,
836 		 * returning the value we actually used in getsockopt
837 		 * is the most desirable behavior.
838 		 */
839 		sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
840 		break;
841 
842 	case SO_RCVBUFFORCE:
843 		if (!capable(CAP_NET_ADMIN)) {
844 			ret = -EPERM;
845 			break;
846 		}
847 
848 		/* No negative values (to prevent underflow, as val will be
849 		 * multiplied by 2).
850 		 */
851 		if (val < 0)
852 			val = 0;
853 		goto set_rcvbuf;
854 
855 	case SO_KEEPALIVE:
856 		if (sk->sk_prot->keepalive)
857 			sk->sk_prot->keepalive(sk, valbool);
858 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
859 		break;
860 
861 	case SO_OOBINLINE:
862 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
863 		break;
864 
865 	case SO_NO_CHECK:
866 		sk->sk_no_check_tx = valbool;
867 		break;
868 
869 	case SO_PRIORITY:
870 		if ((val >= 0 && val <= 6) ||
871 		    ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
872 			sk->sk_priority = val;
873 		else
874 			ret = -EPERM;
875 		break;
876 
877 	case SO_LINGER:
878 		if (optlen < sizeof(ling)) {
879 			ret = -EINVAL;	/* 1003.1g */
880 			break;
881 		}
882 		if (copy_from_user(&ling, optval, sizeof(ling))) {
883 			ret = -EFAULT;
884 			break;
885 		}
886 		if (!ling.l_onoff)
887 			sock_reset_flag(sk, SOCK_LINGER);
888 		else {
889 #if (BITS_PER_LONG == 32)
890 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
891 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
892 			else
893 #endif
894 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
895 			sock_set_flag(sk, SOCK_LINGER);
896 		}
897 		break;
898 
899 	case SO_BSDCOMPAT:
900 		sock_warn_obsolete_bsdism("setsockopt");
901 		break;
902 
903 	case SO_PASSCRED:
904 		if (valbool)
905 			set_bit(SOCK_PASSCRED, &sock->flags);
906 		else
907 			clear_bit(SOCK_PASSCRED, &sock->flags);
908 		break;
909 
910 	case SO_TIMESTAMP_OLD:
911 	case SO_TIMESTAMP_NEW:
912 	case SO_TIMESTAMPNS_OLD:
913 	case SO_TIMESTAMPNS_NEW:
914 		if (valbool)  {
915 			if (optname == SO_TIMESTAMP_NEW || optname == SO_TIMESTAMPNS_NEW)
916 				sock_set_flag(sk, SOCK_TSTAMP_NEW);
917 			else
918 				sock_reset_flag(sk, SOCK_TSTAMP_NEW);
919 
920 			if (optname == SO_TIMESTAMP_OLD || optname == SO_TIMESTAMP_NEW)
921 				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
922 			else
923 				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
924 			sock_set_flag(sk, SOCK_RCVTSTAMP);
925 			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
926 		} else {
927 			sock_reset_flag(sk, SOCK_RCVTSTAMP);
928 			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
929 			sock_reset_flag(sk, SOCK_TSTAMP_NEW);
930 		}
931 		break;
932 
933 	case SO_TIMESTAMPING_NEW:
934 		sock_set_flag(sk, SOCK_TSTAMP_NEW);
935 		/* fall through */
936 	case SO_TIMESTAMPING_OLD:
937 		if (val & ~SOF_TIMESTAMPING_MASK) {
938 			ret = -EINVAL;
939 			break;
940 		}
941 
942 		if (val & SOF_TIMESTAMPING_OPT_ID &&
943 		    !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
944 			if (sk->sk_protocol == IPPROTO_TCP &&
945 			    sk->sk_type == SOCK_STREAM) {
946 				if ((1 << sk->sk_state) &
947 				    (TCPF_CLOSE | TCPF_LISTEN)) {
948 					ret = -EINVAL;
949 					break;
950 				}
951 				sk->sk_tskey = tcp_sk(sk)->snd_una;
952 			} else {
953 				sk->sk_tskey = 0;
954 			}
955 		}
956 
957 		if (val & SOF_TIMESTAMPING_OPT_STATS &&
958 		    !(val & SOF_TIMESTAMPING_OPT_TSONLY)) {
959 			ret = -EINVAL;
960 			break;
961 		}
962 
963 		sk->sk_tsflags = val;
964 		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
965 			sock_enable_timestamp(sk,
966 					      SOCK_TIMESTAMPING_RX_SOFTWARE);
967 		else {
968 			if (optname == SO_TIMESTAMPING_NEW)
969 				sock_reset_flag(sk, SOCK_TSTAMP_NEW);
970 
971 			sock_disable_timestamp(sk,
972 					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
973 		}
974 		break;
975 
976 	case SO_RCVLOWAT:
977 		if (val < 0)
978 			val = INT_MAX;
979 		if (sock->ops->set_rcvlowat)
980 			ret = sock->ops->set_rcvlowat(sk, val);
981 		else
982 			sk->sk_rcvlowat = val ? : 1;
983 		break;
984 
985 	case SO_RCVTIMEO_OLD:
986 	case SO_RCVTIMEO_NEW:
987 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen, optname == SO_RCVTIMEO_OLD);
988 		break;
989 
990 	case SO_SNDTIMEO_OLD:
991 	case SO_SNDTIMEO_NEW:
992 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen, optname == SO_SNDTIMEO_OLD);
993 		break;
994 
995 	case SO_ATTACH_FILTER:
996 		ret = -EINVAL;
997 		if (optlen == sizeof(struct sock_fprog)) {
998 			struct sock_fprog fprog;
999 
1000 			ret = -EFAULT;
1001 			if (copy_from_user(&fprog, optval, sizeof(fprog)))
1002 				break;
1003 
1004 			ret = sk_attach_filter(&fprog, sk);
1005 		}
1006 		break;
1007 
1008 	case SO_ATTACH_BPF:
1009 		ret = -EINVAL;
1010 		if (optlen == sizeof(u32)) {
1011 			u32 ufd;
1012 
1013 			ret = -EFAULT;
1014 			if (copy_from_user(&ufd, optval, sizeof(ufd)))
1015 				break;
1016 
1017 			ret = sk_attach_bpf(ufd, sk);
1018 		}
1019 		break;
1020 
1021 	case SO_ATTACH_REUSEPORT_CBPF:
1022 		ret = -EINVAL;
1023 		if (optlen == sizeof(struct sock_fprog)) {
1024 			struct sock_fprog fprog;
1025 
1026 			ret = -EFAULT;
1027 			if (copy_from_user(&fprog, optval, sizeof(fprog)))
1028 				break;
1029 
1030 			ret = sk_reuseport_attach_filter(&fprog, sk);
1031 		}
1032 		break;
1033 
1034 	case SO_ATTACH_REUSEPORT_EBPF:
1035 		ret = -EINVAL;
1036 		if (optlen == sizeof(u32)) {
1037 			u32 ufd;
1038 
1039 			ret = -EFAULT;
1040 			if (copy_from_user(&ufd, optval, sizeof(ufd)))
1041 				break;
1042 
1043 			ret = sk_reuseport_attach_bpf(ufd, sk);
1044 		}
1045 		break;
1046 
1047 	case SO_DETACH_FILTER:
1048 		ret = sk_detach_filter(sk);
1049 		break;
1050 
1051 	case SO_LOCK_FILTER:
1052 		if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1053 			ret = -EPERM;
1054 		else
1055 			sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1056 		break;
1057 
1058 	case SO_PASSSEC:
1059 		if (valbool)
1060 			set_bit(SOCK_PASSSEC, &sock->flags);
1061 		else
1062 			clear_bit(SOCK_PASSSEC, &sock->flags);
1063 		break;
1064 	case SO_MARK:
1065 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1066 			ret = -EPERM;
1067 		} else if (val != sk->sk_mark) {
1068 			sk->sk_mark = val;
1069 			sk_dst_reset(sk);
1070 		}
1071 		break;
1072 
1073 	case SO_RXQ_OVFL:
1074 		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1075 		break;
1076 
1077 	case SO_WIFI_STATUS:
1078 		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1079 		break;
1080 
1081 	case SO_PEEK_OFF:
1082 		if (sock->ops->set_peek_off)
1083 			ret = sock->ops->set_peek_off(sk, val);
1084 		else
1085 			ret = -EOPNOTSUPP;
1086 		break;
1087 
1088 	case SO_NOFCS:
1089 		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1090 		break;
1091 
1092 	case SO_SELECT_ERR_QUEUE:
1093 		sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1094 		break;
1095 
1096 #ifdef CONFIG_NET_RX_BUSY_POLL
1097 	case SO_BUSY_POLL:
1098 		/* allow unprivileged users to decrease the value */
1099 		if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1100 			ret = -EPERM;
1101 		else {
1102 			if (val < 0)
1103 				ret = -EINVAL;
1104 			else
1105 				sk->sk_ll_usec = val;
1106 		}
1107 		break;
1108 #endif
1109 
1110 	case SO_MAX_PACING_RATE:
1111 		{
1112 		unsigned long ulval = (val == ~0U) ? ~0UL : val;
1113 
1114 		if (sizeof(ulval) != sizeof(val) &&
1115 		    optlen >= sizeof(ulval) &&
1116 		    get_user(ulval, (unsigned long __user *)optval)) {
1117 			ret = -EFAULT;
1118 			break;
1119 		}
1120 		if (ulval != ~0UL)
1121 			cmpxchg(&sk->sk_pacing_status,
1122 				SK_PACING_NONE,
1123 				SK_PACING_NEEDED);
1124 		sk->sk_max_pacing_rate = ulval;
1125 		sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1126 		break;
1127 		}
1128 	case SO_INCOMING_CPU:
1129 		sk->sk_incoming_cpu = val;
1130 		break;
1131 
1132 	case SO_CNX_ADVICE:
1133 		if (val == 1)
1134 			dst_negative_advice(sk);
1135 		break;
1136 
1137 	case SO_ZEROCOPY:
1138 		if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1139 			if (!((sk->sk_type == SOCK_STREAM &&
1140 			       sk->sk_protocol == IPPROTO_TCP) ||
1141 			      (sk->sk_type == SOCK_DGRAM &&
1142 			       sk->sk_protocol == IPPROTO_UDP)))
1143 				ret = -ENOTSUPP;
1144 		} else if (sk->sk_family != PF_RDS) {
1145 			ret = -ENOTSUPP;
1146 		}
1147 		if (!ret) {
1148 			if (val < 0 || val > 1)
1149 				ret = -EINVAL;
1150 			else
1151 				sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1152 		}
1153 		break;
1154 
1155 	case SO_TXTIME:
1156 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1157 			ret = -EPERM;
1158 		} else if (optlen != sizeof(struct sock_txtime)) {
1159 			ret = -EINVAL;
1160 		} else if (copy_from_user(&sk_txtime, optval,
1161 			   sizeof(struct sock_txtime))) {
1162 			ret = -EFAULT;
1163 		} else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1164 			ret = -EINVAL;
1165 		} else {
1166 			sock_valbool_flag(sk, SOCK_TXTIME, true);
1167 			sk->sk_clockid = sk_txtime.clockid;
1168 			sk->sk_txtime_deadline_mode =
1169 				!!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1170 			sk->sk_txtime_report_errors =
1171 				!!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1172 		}
1173 		break;
1174 
1175 	case SO_BINDTOIFINDEX:
1176 		ret = sock_setbindtodevice_locked(sk, val);
1177 		break;
1178 
1179 	default:
1180 		ret = -ENOPROTOOPT;
1181 		break;
1182 	}
1183 	release_sock(sk);
1184 	return ret;
1185 }
1186 EXPORT_SYMBOL(sock_setsockopt);
1187 
1188 
1189 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1190 			  struct ucred *ucred)
1191 {
1192 	ucred->pid = pid_vnr(pid);
1193 	ucred->uid = ucred->gid = -1;
1194 	if (cred) {
1195 		struct user_namespace *current_ns = current_user_ns();
1196 
1197 		ucred->uid = from_kuid_munged(current_ns, cred->euid);
1198 		ucred->gid = from_kgid_munged(current_ns, cred->egid);
1199 	}
1200 }
1201 
1202 static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1203 {
1204 	struct user_namespace *user_ns = current_user_ns();
1205 	int i;
1206 
1207 	for (i = 0; i < src->ngroups; i++)
1208 		if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1209 			return -EFAULT;
1210 
1211 	return 0;
1212 }
1213 
1214 int sock_getsockopt(struct socket *sock, int level, int optname,
1215 		    char __user *optval, int __user *optlen)
1216 {
1217 	struct sock *sk = sock->sk;
1218 
1219 	union {
1220 		int val;
1221 		u64 val64;
1222 		unsigned long ulval;
1223 		struct linger ling;
1224 		struct old_timeval32 tm32;
1225 		struct __kernel_old_timeval tm;
1226 		struct  __kernel_sock_timeval stm;
1227 		struct sock_txtime txtime;
1228 	} v;
1229 
1230 	int lv = sizeof(int);
1231 	int len;
1232 
1233 	if (get_user(len, optlen))
1234 		return -EFAULT;
1235 	if (len < 0)
1236 		return -EINVAL;
1237 
1238 	memset(&v, 0, sizeof(v));
1239 
1240 	switch (optname) {
1241 	case SO_DEBUG:
1242 		v.val = sock_flag(sk, SOCK_DBG);
1243 		break;
1244 
1245 	case SO_DONTROUTE:
1246 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
1247 		break;
1248 
1249 	case SO_BROADCAST:
1250 		v.val = sock_flag(sk, SOCK_BROADCAST);
1251 		break;
1252 
1253 	case SO_SNDBUF:
1254 		v.val = sk->sk_sndbuf;
1255 		break;
1256 
1257 	case SO_RCVBUF:
1258 		v.val = sk->sk_rcvbuf;
1259 		break;
1260 
1261 	case SO_REUSEADDR:
1262 		v.val = sk->sk_reuse;
1263 		break;
1264 
1265 	case SO_REUSEPORT:
1266 		v.val = sk->sk_reuseport;
1267 		break;
1268 
1269 	case SO_KEEPALIVE:
1270 		v.val = sock_flag(sk, SOCK_KEEPOPEN);
1271 		break;
1272 
1273 	case SO_TYPE:
1274 		v.val = sk->sk_type;
1275 		break;
1276 
1277 	case SO_PROTOCOL:
1278 		v.val = sk->sk_protocol;
1279 		break;
1280 
1281 	case SO_DOMAIN:
1282 		v.val = sk->sk_family;
1283 		break;
1284 
1285 	case SO_ERROR:
1286 		v.val = -sock_error(sk);
1287 		if (v.val == 0)
1288 			v.val = xchg(&sk->sk_err_soft, 0);
1289 		break;
1290 
1291 	case SO_OOBINLINE:
1292 		v.val = sock_flag(sk, SOCK_URGINLINE);
1293 		break;
1294 
1295 	case SO_NO_CHECK:
1296 		v.val = sk->sk_no_check_tx;
1297 		break;
1298 
1299 	case SO_PRIORITY:
1300 		v.val = sk->sk_priority;
1301 		break;
1302 
1303 	case SO_LINGER:
1304 		lv		= sizeof(v.ling);
1305 		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
1306 		v.ling.l_linger	= sk->sk_lingertime / HZ;
1307 		break;
1308 
1309 	case SO_BSDCOMPAT:
1310 		sock_warn_obsolete_bsdism("getsockopt");
1311 		break;
1312 
1313 	case SO_TIMESTAMP_OLD:
1314 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1315 				!sock_flag(sk, SOCK_TSTAMP_NEW) &&
1316 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
1317 		break;
1318 
1319 	case SO_TIMESTAMPNS_OLD:
1320 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1321 		break;
1322 
1323 	case SO_TIMESTAMP_NEW:
1324 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1325 		break;
1326 
1327 	case SO_TIMESTAMPNS_NEW:
1328 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1329 		break;
1330 
1331 	case SO_TIMESTAMPING_OLD:
1332 		v.val = sk->sk_tsflags;
1333 		break;
1334 
1335 	case SO_RCVTIMEO_OLD:
1336 	case SO_RCVTIMEO_NEW:
1337 		lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1338 		break;
1339 
1340 	case SO_SNDTIMEO_OLD:
1341 	case SO_SNDTIMEO_NEW:
1342 		lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1343 		break;
1344 
1345 	case SO_RCVLOWAT:
1346 		v.val = sk->sk_rcvlowat;
1347 		break;
1348 
1349 	case SO_SNDLOWAT:
1350 		v.val = 1;
1351 		break;
1352 
1353 	case SO_PASSCRED:
1354 		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1355 		break;
1356 
1357 	case SO_PEERCRED:
1358 	{
1359 		struct ucred peercred;
1360 		if (len > sizeof(peercred))
1361 			len = sizeof(peercred);
1362 		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1363 		if (copy_to_user(optval, &peercred, len))
1364 			return -EFAULT;
1365 		goto lenout;
1366 	}
1367 
1368 	case SO_PEERGROUPS:
1369 	{
1370 		int ret, n;
1371 
1372 		if (!sk->sk_peer_cred)
1373 			return -ENODATA;
1374 
1375 		n = sk->sk_peer_cred->group_info->ngroups;
1376 		if (len < n * sizeof(gid_t)) {
1377 			len = n * sizeof(gid_t);
1378 			return put_user(len, optlen) ? -EFAULT : -ERANGE;
1379 		}
1380 		len = n * sizeof(gid_t);
1381 
1382 		ret = groups_to_user((gid_t __user *)optval,
1383 				     sk->sk_peer_cred->group_info);
1384 		if (ret)
1385 			return ret;
1386 		goto lenout;
1387 	}
1388 
1389 	case SO_PEERNAME:
1390 	{
1391 		char address[128];
1392 
1393 		lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1394 		if (lv < 0)
1395 			return -ENOTCONN;
1396 		if (lv < len)
1397 			return -EINVAL;
1398 		if (copy_to_user(optval, address, len))
1399 			return -EFAULT;
1400 		goto lenout;
1401 	}
1402 
1403 	/* Dubious BSD thing... Probably nobody even uses it, but
1404 	 * the UNIX standard wants it for whatever reason... -DaveM
1405 	 */
1406 	case SO_ACCEPTCONN:
1407 		v.val = sk->sk_state == TCP_LISTEN;
1408 		break;
1409 
1410 	case SO_PASSSEC:
1411 		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1412 		break;
1413 
1414 	case SO_PEERSEC:
1415 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1416 
1417 	case SO_MARK:
1418 		v.val = sk->sk_mark;
1419 		break;
1420 
1421 	case SO_RXQ_OVFL:
1422 		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1423 		break;
1424 
1425 	case SO_WIFI_STATUS:
1426 		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1427 		break;
1428 
1429 	case SO_PEEK_OFF:
1430 		if (!sock->ops->set_peek_off)
1431 			return -EOPNOTSUPP;
1432 
1433 		v.val = sk->sk_peek_off;
1434 		break;
1435 	case SO_NOFCS:
1436 		v.val = sock_flag(sk, SOCK_NOFCS);
1437 		break;
1438 
1439 	case SO_BINDTODEVICE:
1440 		return sock_getbindtodevice(sk, optval, optlen, len);
1441 
1442 	case SO_GET_FILTER:
1443 		len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1444 		if (len < 0)
1445 			return len;
1446 
1447 		goto lenout;
1448 
1449 	case SO_LOCK_FILTER:
1450 		v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1451 		break;
1452 
1453 	case SO_BPF_EXTENSIONS:
1454 		v.val = bpf_tell_extensions();
1455 		break;
1456 
1457 	case SO_SELECT_ERR_QUEUE:
1458 		v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1459 		break;
1460 
1461 #ifdef CONFIG_NET_RX_BUSY_POLL
1462 	case SO_BUSY_POLL:
1463 		v.val = sk->sk_ll_usec;
1464 		break;
1465 #endif
1466 
1467 	case SO_MAX_PACING_RATE:
1468 		if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1469 			lv = sizeof(v.ulval);
1470 			v.ulval = sk->sk_max_pacing_rate;
1471 		} else {
1472 			/* 32bit version */
1473 			v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1474 		}
1475 		break;
1476 
1477 	case SO_INCOMING_CPU:
1478 		v.val = sk->sk_incoming_cpu;
1479 		break;
1480 
1481 	case SO_MEMINFO:
1482 	{
1483 		u32 meminfo[SK_MEMINFO_VARS];
1484 
1485 		if (get_user(len, optlen))
1486 			return -EFAULT;
1487 
1488 		sk_get_meminfo(sk, meminfo);
1489 
1490 		len = min_t(unsigned int, len, sizeof(meminfo));
1491 		if (copy_to_user(optval, &meminfo, len))
1492 			return -EFAULT;
1493 
1494 		goto lenout;
1495 	}
1496 
1497 #ifdef CONFIG_NET_RX_BUSY_POLL
1498 	case SO_INCOMING_NAPI_ID:
1499 		v.val = READ_ONCE(sk->sk_napi_id);
1500 
1501 		/* aggregate non-NAPI IDs down to 0 */
1502 		if (v.val < MIN_NAPI_ID)
1503 			v.val = 0;
1504 
1505 		break;
1506 #endif
1507 
1508 	case SO_COOKIE:
1509 		lv = sizeof(u64);
1510 		if (len < lv)
1511 			return -EINVAL;
1512 		v.val64 = sock_gen_cookie(sk);
1513 		break;
1514 
1515 	case SO_ZEROCOPY:
1516 		v.val = sock_flag(sk, SOCK_ZEROCOPY);
1517 		break;
1518 
1519 	case SO_TXTIME:
1520 		lv = sizeof(v.txtime);
1521 		v.txtime.clockid = sk->sk_clockid;
1522 		v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1523 				  SOF_TXTIME_DEADLINE_MODE : 0;
1524 		v.txtime.flags |= sk->sk_txtime_report_errors ?
1525 				  SOF_TXTIME_REPORT_ERRORS : 0;
1526 		break;
1527 
1528 	case SO_BINDTOIFINDEX:
1529 		v.val = sk->sk_bound_dev_if;
1530 		break;
1531 
1532 	default:
1533 		/* We implement the SO_SNDLOWAT etc to not be settable
1534 		 * (1003.1g 7).
1535 		 */
1536 		return -ENOPROTOOPT;
1537 	}
1538 
1539 	if (len > lv)
1540 		len = lv;
1541 	if (copy_to_user(optval, &v, len))
1542 		return -EFAULT;
1543 lenout:
1544 	if (put_user(len, optlen))
1545 		return -EFAULT;
1546 	return 0;
1547 }
1548 
1549 /*
1550  * Initialize an sk_lock.
1551  *
1552  * (We also register the sk_lock with the lock validator.)
1553  */
1554 static inline void sock_lock_init(struct sock *sk)
1555 {
1556 	if (sk->sk_kern_sock)
1557 		sock_lock_init_class_and_name(
1558 			sk,
1559 			af_family_kern_slock_key_strings[sk->sk_family],
1560 			af_family_kern_slock_keys + sk->sk_family,
1561 			af_family_kern_key_strings[sk->sk_family],
1562 			af_family_kern_keys + sk->sk_family);
1563 	else
1564 		sock_lock_init_class_and_name(
1565 			sk,
1566 			af_family_slock_key_strings[sk->sk_family],
1567 			af_family_slock_keys + sk->sk_family,
1568 			af_family_key_strings[sk->sk_family],
1569 			af_family_keys + sk->sk_family);
1570 }
1571 
1572 /*
1573  * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1574  * even temporarly, because of RCU lookups. sk_node should also be left as is.
1575  * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1576  */
1577 static void sock_copy(struct sock *nsk, const struct sock *osk)
1578 {
1579 #ifdef CONFIG_SECURITY_NETWORK
1580 	void *sptr = nsk->sk_security;
1581 #endif
1582 	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1583 
1584 	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1585 	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1586 
1587 #ifdef CONFIG_SECURITY_NETWORK
1588 	nsk->sk_security = sptr;
1589 	security_sk_clone(osk, nsk);
1590 #endif
1591 }
1592 
1593 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1594 		int family)
1595 {
1596 	struct sock *sk;
1597 	struct kmem_cache *slab;
1598 
1599 	slab = prot->slab;
1600 	if (slab != NULL) {
1601 		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1602 		if (!sk)
1603 			return sk;
1604 		if (priority & __GFP_ZERO)
1605 			sk_prot_clear_nulls(sk, prot->obj_size);
1606 	} else
1607 		sk = kmalloc(prot->obj_size, priority);
1608 
1609 	if (sk != NULL) {
1610 		if (security_sk_alloc(sk, family, priority))
1611 			goto out_free;
1612 
1613 		if (!try_module_get(prot->owner))
1614 			goto out_free_sec;
1615 		sk_tx_queue_clear(sk);
1616 	}
1617 
1618 	return sk;
1619 
1620 out_free_sec:
1621 	security_sk_free(sk);
1622 out_free:
1623 	if (slab != NULL)
1624 		kmem_cache_free(slab, sk);
1625 	else
1626 		kfree(sk);
1627 	return NULL;
1628 }
1629 
1630 static void sk_prot_free(struct proto *prot, struct sock *sk)
1631 {
1632 	struct kmem_cache *slab;
1633 	struct module *owner;
1634 
1635 	owner = prot->owner;
1636 	slab = prot->slab;
1637 
1638 	cgroup_sk_free(&sk->sk_cgrp_data);
1639 	mem_cgroup_sk_free(sk);
1640 	security_sk_free(sk);
1641 	if (slab != NULL)
1642 		kmem_cache_free(slab, sk);
1643 	else
1644 		kfree(sk);
1645 	module_put(owner);
1646 }
1647 
1648 /**
1649  *	sk_alloc - All socket objects are allocated here
1650  *	@net: the applicable net namespace
1651  *	@family: protocol family
1652  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1653  *	@prot: struct proto associated with this new sock instance
1654  *	@kern: is this to be a kernel socket?
1655  */
1656 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1657 		      struct proto *prot, int kern)
1658 {
1659 	struct sock *sk;
1660 
1661 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1662 	if (sk) {
1663 		sk->sk_family = family;
1664 		/*
1665 		 * See comment in struct sock definition to understand
1666 		 * why we need sk_prot_creator -acme
1667 		 */
1668 		sk->sk_prot = sk->sk_prot_creator = prot;
1669 		sk->sk_kern_sock = kern;
1670 		sock_lock_init(sk);
1671 		sk->sk_net_refcnt = kern ? 0 : 1;
1672 		if (likely(sk->sk_net_refcnt)) {
1673 			get_net(net);
1674 			sock_inuse_add(net, 1);
1675 		}
1676 
1677 		sock_net_set(sk, net);
1678 		refcount_set(&sk->sk_wmem_alloc, 1);
1679 
1680 		mem_cgroup_sk_alloc(sk);
1681 		cgroup_sk_alloc(&sk->sk_cgrp_data);
1682 		sock_update_classid(&sk->sk_cgrp_data);
1683 		sock_update_netprioidx(&sk->sk_cgrp_data);
1684 	}
1685 
1686 	return sk;
1687 }
1688 EXPORT_SYMBOL(sk_alloc);
1689 
1690 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
1691  * grace period. This is the case for UDP sockets and TCP listeners.
1692  */
1693 static void __sk_destruct(struct rcu_head *head)
1694 {
1695 	struct sock *sk = container_of(head, struct sock, sk_rcu);
1696 	struct sk_filter *filter;
1697 
1698 	if (sk->sk_destruct)
1699 		sk->sk_destruct(sk);
1700 
1701 	filter = rcu_dereference_check(sk->sk_filter,
1702 				       refcount_read(&sk->sk_wmem_alloc) == 0);
1703 	if (filter) {
1704 		sk_filter_uncharge(sk, filter);
1705 		RCU_INIT_POINTER(sk->sk_filter, NULL);
1706 	}
1707 	if (rcu_access_pointer(sk->sk_reuseport_cb))
1708 		reuseport_detach_sock(sk);
1709 
1710 	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
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 
1855 		newsk->sk_err	   = 0;
1856 		newsk->sk_err_soft = 0;
1857 		newsk->sk_priority = 0;
1858 		newsk->sk_incoming_cpu = raw_smp_processor_id();
1859 		if (likely(newsk->sk_net_refcnt))
1860 			sock_inuse_add(sock_net(newsk), 1);
1861 
1862 		/*
1863 		 * Before updating sk_refcnt, we must commit prior changes to memory
1864 		 * (Documentation/RCU/rculist_nulls.txt for details)
1865 		 */
1866 		smp_wmb();
1867 		refcount_set(&newsk->sk_refcnt, 2);
1868 
1869 		/*
1870 		 * Increment the counter in the same struct proto as the master
1871 		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1872 		 * is the same as sk->sk_prot->socks, as this field was copied
1873 		 * with memcpy).
1874 		 *
1875 		 * This _changes_ the previous behaviour, where
1876 		 * tcp_create_openreq_child always was incrementing the
1877 		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1878 		 * to be taken into account in all callers. -acme
1879 		 */
1880 		sk_refcnt_debug_inc(newsk);
1881 		sk_set_socket(newsk, NULL);
1882 		RCU_INIT_POINTER(newsk->sk_wq, NULL);
1883 
1884 		if (newsk->sk_prot->sockets_allocated)
1885 			sk_sockets_allocated_inc(newsk);
1886 
1887 		if (sock_needs_netstamp(sk) &&
1888 		    newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1889 			net_enable_timestamp();
1890 	}
1891 out:
1892 	return newsk;
1893 }
1894 EXPORT_SYMBOL_GPL(sk_clone_lock);
1895 
1896 void sk_free_unlock_clone(struct sock *sk)
1897 {
1898 	/* It is still raw copy of parent, so invalidate
1899 	 * destructor and make plain sk_free() */
1900 	sk->sk_destruct = NULL;
1901 	bh_unlock_sock(sk);
1902 	sk_free(sk);
1903 }
1904 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
1905 
1906 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1907 {
1908 	u32 max_segs = 1;
1909 
1910 	sk_dst_set(sk, dst);
1911 	sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps;
1912 	if (sk->sk_route_caps & NETIF_F_GSO)
1913 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1914 	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1915 	if (sk_can_gso(sk)) {
1916 		if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
1917 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1918 		} else {
1919 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1920 			sk->sk_gso_max_size = dst->dev->gso_max_size;
1921 			max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1922 		}
1923 	}
1924 	sk->sk_gso_max_segs = max_segs;
1925 }
1926 EXPORT_SYMBOL_GPL(sk_setup_caps);
1927 
1928 /*
1929  *	Simple resource managers for sockets.
1930  */
1931 
1932 
1933 /*
1934  * Write buffer destructor automatically called from kfree_skb.
1935  */
1936 void sock_wfree(struct sk_buff *skb)
1937 {
1938 	struct sock *sk = skb->sk;
1939 	unsigned int len = skb->truesize;
1940 
1941 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1942 		/*
1943 		 * Keep a reference on sk_wmem_alloc, this will be released
1944 		 * after sk_write_space() call
1945 		 */
1946 		WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
1947 		sk->sk_write_space(sk);
1948 		len = 1;
1949 	}
1950 	/*
1951 	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1952 	 * could not do because of in-flight packets
1953 	 */
1954 	if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
1955 		__sk_free(sk);
1956 }
1957 EXPORT_SYMBOL(sock_wfree);
1958 
1959 /* This variant of sock_wfree() is used by TCP,
1960  * since it sets SOCK_USE_WRITE_QUEUE.
1961  */
1962 void __sock_wfree(struct sk_buff *skb)
1963 {
1964 	struct sock *sk = skb->sk;
1965 
1966 	if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
1967 		__sk_free(sk);
1968 }
1969 
1970 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1971 {
1972 	skb_orphan(skb);
1973 	skb->sk = sk;
1974 #ifdef CONFIG_INET
1975 	if (unlikely(!sk_fullsock(sk))) {
1976 		skb->destructor = sock_edemux;
1977 		sock_hold(sk);
1978 		return;
1979 	}
1980 #endif
1981 	skb->destructor = sock_wfree;
1982 	skb_set_hash_from_sk(skb, sk);
1983 	/*
1984 	 * We used to take a refcount on sk, but following operation
1985 	 * is enough to guarantee sk_free() wont free this sock until
1986 	 * all in-flight packets are completed
1987 	 */
1988 	refcount_add(skb->truesize, &sk->sk_wmem_alloc);
1989 }
1990 EXPORT_SYMBOL(skb_set_owner_w);
1991 
1992 /* This helper is used by netem, as it can hold packets in its
1993  * delay queue. We want to allow the owner socket to send more
1994  * packets, as if they were already TX completed by a typical driver.
1995  * But we also want to keep skb->sk set because some packet schedulers
1996  * rely on it (sch_fq for example).
1997  */
1998 void skb_orphan_partial(struct sk_buff *skb)
1999 {
2000 	if (skb_is_tcp_pure_ack(skb))
2001 		return;
2002 
2003 	if (skb->destructor == sock_wfree
2004 #ifdef CONFIG_INET
2005 	    || skb->destructor == tcp_wfree
2006 #endif
2007 		) {
2008 		struct sock *sk = skb->sk;
2009 
2010 		if (refcount_inc_not_zero(&sk->sk_refcnt)) {
2011 			WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc));
2012 			skb->destructor = sock_efree;
2013 		}
2014 	} else {
2015 		skb_orphan(skb);
2016 	}
2017 }
2018 EXPORT_SYMBOL(skb_orphan_partial);
2019 
2020 /*
2021  * Read buffer destructor automatically called from kfree_skb.
2022  */
2023 void sock_rfree(struct sk_buff *skb)
2024 {
2025 	struct sock *sk = skb->sk;
2026 	unsigned int len = skb->truesize;
2027 
2028 	atomic_sub(len, &sk->sk_rmem_alloc);
2029 	sk_mem_uncharge(sk, len);
2030 }
2031 EXPORT_SYMBOL(sock_rfree);
2032 
2033 /*
2034  * Buffer destructor for skbs that are not used directly in read or write
2035  * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2036  */
2037 void sock_efree(struct sk_buff *skb)
2038 {
2039 	sock_put(skb->sk);
2040 }
2041 EXPORT_SYMBOL(sock_efree);
2042 
2043 kuid_t sock_i_uid(struct sock *sk)
2044 {
2045 	kuid_t uid;
2046 
2047 	read_lock_bh(&sk->sk_callback_lock);
2048 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2049 	read_unlock_bh(&sk->sk_callback_lock);
2050 	return uid;
2051 }
2052 EXPORT_SYMBOL(sock_i_uid);
2053 
2054 unsigned long sock_i_ino(struct sock *sk)
2055 {
2056 	unsigned long ino;
2057 
2058 	read_lock_bh(&sk->sk_callback_lock);
2059 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2060 	read_unlock_bh(&sk->sk_callback_lock);
2061 	return ino;
2062 }
2063 EXPORT_SYMBOL(sock_i_ino);
2064 
2065 /*
2066  * Allocate a skb from the socket's send buffer.
2067  */
2068 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2069 			     gfp_t priority)
2070 {
2071 	if (force || refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
2072 		struct sk_buff *skb = alloc_skb(size, priority);
2073 		if (skb) {
2074 			skb_set_owner_w(skb, sk);
2075 			return skb;
2076 		}
2077 	}
2078 	return NULL;
2079 }
2080 EXPORT_SYMBOL(sock_wmalloc);
2081 
2082 static void sock_ofree(struct sk_buff *skb)
2083 {
2084 	struct sock *sk = skb->sk;
2085 
2086 	atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2087 }
2088 
2089 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2090 			     gfp_t priority)
2091 {
2092 	struct sk_buff *skb;
2093 
2094 	/* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2095 	if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2096 	    sysctl_optmem_max)
2097 		return NULL;
2098 
2099 	skb = alloc_skb(size, priority);
2100 	if (!skb)
2101 		return NULL;
2102 
2103 	atomic_add(skb->truesize, &sk->sk_omem_alloc);
2104 	skb->sk = sk;
2105 	skb->destructor = sock_ofree;
2106 	return skb;
2107 }
2108 
2109 /*
2110  * Allocate a memory block from the socket's option memory buffer.
2111  */
2112 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2113 {
2114 	if ((unsigned int)size <= sysctl_optmem_max &&
2115 	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
2116 		void *mem;
2117 		/* First do the add, to avoid the race if kmalloc
2118 		 * might sleep.
2119 		 */
2120 		atomic_add(size, &sk->sk_omem_alloc);
2121 		mem = kmalloc(size, priority);
2122 		if (mem)
2123 			return mem;
2124 		atomic_sub(size, &sk->sk_omem_alloc);
2125 	}
2126 	return NULL;
2127 }
2128 EXPORT_SYMBOL(sock_kmalloc);
2129 
2130 /* Free an option memory block. Note, we actually want the inline
2131  * here as this allows gcc to detect the nullify and fold away the
2132  * condition entirely.
2133  */
2134 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2135 				  const bool nullify)
2136 {
2137 	if (WARN_ON_ONCE(!mem))
2138 		return;
2139 	if (nullify)
2140 		kzfree(mem);
2141 	else
2142 		kfree(mem);
2143 	atomic_sub(size, &sk->sk_omem_alloc);
2144 }
2145 
2146 void sock_kfree_s(struct sock *sk, void *mem, int size)
2147 {
2148 	__sock_kfree_s(sk, mem, size, false);
2149 }
2150 EXPORT_SYMBOL(sock_kfree_s);
2151 
2152 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2153 {
2154 	__sock_kfree_s(sk, mem, size, true);
2155 }
2156 EXPORT_SYMBOL(sock_kzfree_s);
2157 
2158 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2159    I think, these locks should be removed for datagram sockets.
2160  */
2161 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2162 {
2163 	DEFINE_WAIT(wait);
2164 
2165 	sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2166 	for (;;) {
2167 		if (!timeo)
2168 			break;
2169 		if (signal_pending(current))
2170 			break;
2171 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2172 		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2173 		if (refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
2174 			break;
2175 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2176 			break;
2177 		if (sk->sk_err)
2178 			break;
2179 		timeo = schedule_timeout(timeo);
2180 	}
2181 	finish_wait(sk_sleep(sk), &wait);
2182 	return timeo;
2183 }
2184 
2185 
2186 /*
2187  *	Generic send/receive buffer handlers
2188  */
2189 
2190 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2191 				     unsigned long data_len, int noblock,
2192 				     int *errcode, int max_page_order)
2193 {
2194 	struct sk_buff *skb;
2195 	long timeo;
2196 	int err;
2197 
2198 	timeo = sock_sndtimeo(sk, noblock);
2199 	for (;;) {
2200 		err = sock_error(sk);
2201 		if (err != 0)
2202 			goto failure;
2203 
2204 		err = -EPIPE;
2205 		if (sk->sk_shutdown & SEND_SHUTDOWN)
2206 			goto failure;
2207 
2208 		if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
2209 			break;
2210 
2211 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2212 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2213 		err = -EAGAIN;
2214 		if (!timeo)
2215 			goto failure;
2216 		if (signal_pending(current))
2217 			goto interrupted;
2218 		timeo = sock_wait_for_wmem(sk, timeo);
2219 	}
2220 	skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2221 				   errcode, sk->sk_allocation);
2222 	if (skb)
2223 		skb_set_owner_w(skb, sk);
2224 	return skb;
2225 
2226 interrupted:
2227 	err = sock_intr_errno(timeo);
2228 failure:
2229 	*errcode = err;
2230 	return NULL;
2231 }
2232 EXPORT_SYMBOL(sock_alloc_send_pskb);
2233 
2234 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2235 				    int noblock, int *errcode)
2236 {
2237 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2238 }
2239 EXPORT_SYMBOL(sock_alloc_send_skb);
2240 
2241 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2242 		     struct sockcm_cookie *sockc)
2243 {
2244 	u32 tsflags;
2245 
2246 	switch (cmsg->cmsg_type) {
2247 	case SO_MARK:
2248 		if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2249 			return -EPERM;
2250 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2251 			return -EINVAL;
2252 		sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2253 		break;
2254 	case SO_TIMESTAMPING_OLD:
2255 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2256 			return -EINVAL;
2257 
2258 		tsflags = *(u32 *)CMSG_DATA(cmsg);
2259 		if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2260 			return -EINVAL;
2261 
2262 		sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2263 		sockc->tsflags |= tsflags;
2264 		break;
2265 	case SCM_TXTIME:
2266 		if (!sock_flag(sk, SOCK_TXTIME))
2267 			return -EINVAL;
2268 		if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2269 			return -EINVAL;
2270 		sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2271 		break;
2272 	/* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2273 	case SCM_RIGHTS:
2274 	case SCM_CREDENTIALS:
2275 		break;
2276 	default:
2277 		return -EINVAL;
2278 	}
2279 	return 0;
2280 }
2281 EXPORT_SYMBOL(__sock_cmsg_send);
2282 
2283 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2284 		   struct sockcm_cookie *sockc)
2285 {
2286 	struct cmsghdr *cmsg;
2287 	int ret;
2288 
2289 	for_each_cmsghdr(cmsg, msg) {
2290 		if (!CMSG_OK(msg, cmsg))
2291 			return -EINVAL;
2292 		if (cmsg->cmsg_level != SOL_SOCKET)
2293 			continue;
2294 		ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2295 		if (ret)
2296 			return ret;
2297 	}
2298 	return 0;
2299 }
2300 EXPORT_SYMBOL(sock_cmsg_send);
2301 
2302 static void sk_enter_memory_pressure(struct sock *sk)
2303 {
2304 	if (!sk->sk_prot->enter_memory_pressure)
2305 		return;
2306 
2307 	sk->sk_prot->enter_memory_pressure(sk);
2308 }
2309 
2310 static void sk_leave_memory_pressure(struct sock *sk)
2311 {
2312 	if (sk->sk_prot->leave_memory_pressure) {
2313 		sk->sk_prot->leave_memory_pressure(sk);
2314 	} else {
2315 		unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2316 
2317 		if (memory_pressure && *memory_pressure)
2318 			*memory_pressure = 0;
2319 	}
2320 }
2321 
2322 /* On 32bit arches, an skb frag is limited to 2^15 */
2323 #define SKB_FRAG_PAGE_ORDER	get_order(32768)
2324 
2325 /**
2326  * skb_page_frag_refill - check that a page_frag contains enough room
2327  * @sz: minimum size of the fragment we want to get
2328  * @pfrag: pointer to page_frag
2329  * @gfp: priority for memory allocation
2330  *
2331  * Note: While this allocator tries to use high order pages, there is
2332  * no guarantee that allocations succeed. Therefore, @sz MUST be
2333  * less or equal than PAGE_SIZE.
2334  */
2335 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2336 {
2337 	if (pfrag->page) {
2338 		if (page_ref_count(pfrag->page) == 1) {
2339 			pfrag->offset = 0;
2340 			return true;
2341 		}
2342 		if (pfrag->offset + sz <= pfrag->size)
2343 			return true;
2344 		put_page(pfrag->page);
2345 	}
2346 
2347 	pfrag->offset = 0;
2348 	if (SKB_FRAG_PAGE_ORDER) {
2349 		/* Avoid direct reclaim but allow kswapd to wake */
2350 		pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2351 					  __GFP_COMP | __GFP_NOWARN |
2352 					  __GFP_NORETRY,
2353 					  SKB_FRAG_PAGE_ORDER);
2354 		if (likely(pfrag->page)) {
2355 			pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2356 			return true;
2357 		}
2358 	}
2359 	pfrag->page = alloc_page(gfp);
2360 	if (likely(pfrag->page)) {
2361 		pfrag->size = PAGE_SIZE;
2362 		return true;
2363 	}
2364 	return false;
2365 }
2366 EXPORT_SYMBOL(skb_page_frag_refill);
2367 
2368 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2369 {
2370 	if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2371 		return true;
2372 
2373 	sk_enter_memory_pressure(sk);
2374 	sk_stream_moderate_sndbuf(sk);
2375 	return false;
2376 }
2377 EXPORT_SYMBOL(sk_page_frag_refill);
2378 
2379 static void __lock_sock(struct sock *sk)
2380 	__releases(&sk->sk_lock.slock)
2381 	__acquires(&sk->sk_lock.slock)
2382 {
2383 	DEFINE_WAIT(wait);
2384 
2385 	for (;;) {
2386 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2387 					TASK_UNINTERRUPTIBLE);
2388 		spin_unlock_bh(&sk->sk_lock.slock);
2389 		schedule();
2390 		spin_lock_bh(&sk->sk_lock.slock);
2391 		if (!sock_owned_by_user(sk))
2392 			break;
2393 	}
2394 	finish_wait(&sk->sk_lock.wq, &wait);
2395 }
2396 
2397 void __release_sock(struct sock *sk)
2398 	__releases(&sk->sk_lock.slock)
2399 	__acquires(&sk->sk_lock.slock)
2400 {
2401 	struct sk_buff *skb, *next;
2402 
2403 	while ((skb = sk->sk_backlog.head) != NULL) {
2404 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2405 
2406 		spin_unlock_bh(&sk->sk_lock.slock);
2407 
2408 		do {
2409 			next = skb->next;
2410 			prefetch(next);
2411 			WARN_ON_ONCE(skb_dst_is_noref(skb));
2412 			skb_mark_not_on_list(skb);
2413 			sk_backlog_rcv(sk, skb);
2414 
2415 			cond_resched();
2416 
2417 			skb = next;
2418 		} while (skb != NULL);
2419 
2420 		spin_lock_bh(&sk->sk_lock.slock);
2421 	}
2422 
2423 	/*
2424 	 * Doing the zeroing here guarantee we can not loop forever
2425 	 * while a wild producer attempts to flood us.
2426 	 */
2427 	sk->sk_backlog.len = 0;
2428 }
2429 
2430 void __sk_flush_backlog(struct sock *sk)
2431 {
2432 	spin_lock_bh(&sk->sk_lock.slock);
2433 	__release_sock(sk);
2434 	spin_unlock_bh(&sk->sk_lock.slock);
2435 }
2436 
2437 /**
2438  * sk_wait_data - wait for data to arrive at sk_receive_queue
2439  * @sk:    sock to wait on
2440  * @timeo: for how long
2441  * @skb:   last skb seen on sk_receive_queue
2442  *
2443  * Now socket state including sk->sk_err is changed only under lock,
2444  * hence we may omit checks after joining wait queue.
2445  * We check receive queue before schedule() only as optimization;
2446  * it is very likely that release_sock() added new data.
2447  */
2448 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2449 {
2450 	DEFINE_WAIT_FUNC(wait, woken_wake_function);
2451 	int rc;
2452 
2453 	add_wait_queue(sk_sleep(sk), &wait);
2454 	sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2455 	rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2456 	sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2457 	remove_wait_queue(sk_sleep(sk), &wait);
2458 	return rc;
2459 }
2460 EXPORT_SYMBOL(sk_wait_data);
2461 
2462 /**
2463  *	__sk_mem_raise_allocated - increase memory_allocated
2464  *	@sk: socket
2465  *	@size: memory size to allocate
2466  *	@amt: pages to allocate
2467  *	@kind: allocation type
2468  *
2469  *	Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2470  */
2471 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2472 {
2473 	struct proto *prot = sk->sk_prot;
2474 	long allocated = sk_memory_allocated_add(sk, amt);
2475 	bool charged = true;
2476 
2477 	if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2478 	    !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt)))
2479 		goto suppress_allocation;
2480 
2481 	/* Under limit. */
2482 	if (allocated <= sk_prot_mem_limits(sk, 0)) {
2483 		sk_leave_memory_pressure(sk);
2484 		return 1;
2485 	}
2486 
2487 	/* Under pressure. */
2488 	if (allocated > sk_prot_mem_limits(sk, 1))
2489 		sk_enter_memory_pressure(sk);
2490 
2491 	/* Over hard limit. */
2492 	if (allocated > sk_prot_mem_limits(sk, 2))
2493 		goto suppress_allocation;
2494 
2495 	/* guarantee minimum buffer size under pressure */
2496 	if (kind == SK_MEM_RECV) {
2497 		if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2498 			return 1;
2499 
2500 	} else { /* SK_MEM_SEND */
2501 		int wmem0 = sk_get_wmem0(sk, prot);
2502 
2503 		if (sk->sk_type == SOCK_STREAM) {
2504 			if (sk->sk_wmem_queued < wmem0)
2505 				return 1;
2506 		} else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
2507 				return 1;
2508 		}
2509 	}
2510 
2511 	if (sk_has_memory_pressure(sk)) {
2512 		u64 alloc;
2513 
2514 		if (!sk_under_memory_pressure(sk))
2515 			return 1;
2516 		alloc = sk_sockets_allocated_read_positive(sk);
2517 		if (sk_prot_mem_limits(sk, 2) > alloc *
2518 		    sk_mem_pages(sk->sk_wmem_queued +
2519 				 atomic_read(&sk->sk_rmem_alloc) +
2520 				 sk->sk_forward_alloc))
2521 			return 1;
2522 	}
2523 
2524 suppress_allocation:
2525 
2526 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2527 		sk_stream_moderate_sndbuf(sk);
2528 
2529 		/* Fail only if socket is _under_ its sndbuf.
2530 		 * In this case we cannot block, so that we have to fail.
2531 		 */
2532 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2533 			return 1;
2534 	}
2535 
2536 	if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
2537 		trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
2538 
2539 	sk_memory_allocated_sub(sk, amt);
2540 
2541 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2542 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2543 
2544 	return 0;
2545 }
2546 EXPORT_SYMBOL(__sk_mem_raise_allocated);
2547 
2548 /**
2549  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2550  *	@sk: socket
2551  *	@size: memory size to allocate
2552  *	@kind: allocation type
2553  *
2554  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2555  *	rmem allocation. This function assumes that protocols which have
2556  *	memory_pressure use sk_wmem_queued as write buffer accounting.
2557  */
2558 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2559 {
2560 	int ret, amt = sk_mem_pages(size);
2561 
2562 	sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2563 	ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2564 	if (!ret)
2565 		sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2566 	return ret;
2567 }
2568 EXPORT_SYMBOL(__sk_mem_schedule);
2569 
2570 /**
2571  *	__sk_mem_reduce_allocated - reclaim memory_allocated
2572  *	@sk: socket
2573  *	@amount: number of quanta
2574  *
2575  *	Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2576  */
2577 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2578 {
2579 	sk_memory_allocated_sub(sk, amount);
2580 
2581 	if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2582 		mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2583 
2584 	if (sk_under_memory_pressure(sk) &&
2585 	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2586 		sk_leave_memory_pressure(sk);
2587 }
2588 EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2589 
2590 /**
2591  *	__sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2592  *	@sk: socket
2593  *	@amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2594  */
2595 void __sk_mem_reclaim(struct sock *sk, int amount)
2596 {
2597 	amount >>= SK_MEM_QUANTUM_SHIFT;
2598 	sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2599 	__sk_mem_reduce_allocated(sk, amount);
2600 }
2601 EXPORT_SYMBOL(__sk_mem_reclaim);
2602 
2603 int sk_set_peek_off(struct sock *sk, int val)
2604 {
2605 	sk->sk_peek_off = val;
2606 	return 0;
2607 }
2608 EXPORT_SYMBOL_GPL(sk_set_peek_off);
2609 
2610 /*
2611  * Set of default routines for initialising struct proto_ops when
2612  * the protocol does not support a particular function. In certain
2613  * cases where it makes no sense for a protocol to have a "do nothing"
2614  * function, some default processing is provided.
2615  */
2616 
2617 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2618 {
2619 	return -EOPNOTSUPP;
2620 }
2621 EXPORT_SYMBOL(sock_no_bind);
2622 
2623 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2624 		    int len, int flags)
2625 {
2626 	return -EOPNOTSUPP;
2627 }
2628 EXPORT_SYMBOL(sock_no_connect);
2629 
2630 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2631 {
2632 	return -EOPNOTSUPP;
2633 }
2634 EXPORT_SYMBOL(sock_no_socketpair);
2635 
2636 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2637 		   bool kern)
2638 {
2639 	return -EOPNOTSUPP;
2640 }
2641 EXPORT_SYMBOL(sock_no_accept);
2642 
2643 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2644 		    int peer)
2645 {
2646 	return -EOPNOTSUPP;
2647 }
2648 EXPORT_SYMBOL(sock_no_getname);
2649 
2650 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2651 {
2652 	return -EOPNOTSUPP;
2653 }
2654 EXPORT_SYMBOL(sock_no_ioctl);
2655 
2656 int sock_no_listen(struct socket *sock, int backlog)
2657 {
2658 	return -EOPNOTSUPP;
2659 }
2660 EXPORT_SYMBOL(sock_no_listen);
2661 
2662 int sock_no_shutdown(struct socket *sock, int how)
2663 {
2664 	return -EOPNOTSUPP;
2665 }
2666 EXPORT_SYMBOL(sock_no_shutdown);
2667 
2668 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2669 		    char __user *optval, unsigned int optlen)
2670 {
2671 	return -EOPNOTSUPP;
2672 }
2673 EXPORT_SYMBOL(sock_no_setsockopt);
2674 
2675 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2676 		    char __user *optval, int __user *optlen)
2677 {
2678 	return -EOPNOTSUPP;
2679 }
2680 EXPORT_SYMBOL(sock_no_getsockopt);
2681 
2682 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2683 {
2684 	return -EOPNOTSUPP;
2685 }
2686 EXPORT_SYMBOL(sock_no_sendmsg);
2687 
2688 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
2689 {
2690 	return -EOPNOTSUPP;
2691 }
2692 EXPORT_SYMBOL(sock_no_sendmsg_locked);
2693 
2694 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2695 		    int flags)
2696 {
2697 	return -EOPNOTSUPP;
2698 }
2699 EXPORT_SYMBOL(sock_no_recvmsg);
2700 
2701 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2702 {
2703 	/* Mirror missing mmap method error code */
2704 	return -ENODEV;
2705 }
2706 EXPORT_SYMBOL(sock_no_mmap);
2707 
2708 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2709 {
2710 	ssize_t res;
2711 	struct msghdr msg = {.msg_flags = flags};
2712 	struct kvec iov;
2713 	char *kaddr = kmap(page);
2714 	iov.iov_base = kaddr + offset;
2715 	iov.iov_len = size;
2716 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2717 	kunmap(page);
2718 	return res;
2719 }
2720 EXPORT_SYMBOL(sock_no_sendpage);
2721 
2722 ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
2723 				int offset, size_t size, int flags)
2724 {
2725 	ssize_t res;
2726 	struct msghdr msg = {.msg_flags = flags};
2727 	struct kvec iov;
2728 	char *kaddr = kmap(page);
2729 
2730 	iov.iov_base = kaddr + offset;
2731 	iov.iov_len = size;
2732 	res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
2733 	kunmap(page);
2734 	return res;
2735 }
2736 EXPORT_SYMBOL(sock_no_sendpage_locked);
2737 
2738 /*
2739  *	Default Socket Callbacks
2740  */
2741 
2742 static void sock_def_wakeup(struct sock *sk)
2743 {
2744 	struct socket_wq *wq;
2745 
2746 	rcu_read_lock();
2747 	wq = rcu_dereference(sk->sk_wq);
2748 	if (skwq_has_sleeper(wq))
2749 		wake_up_interruptible_all(&wq->wait);
2750 	rcu_read_unlock();
2751 }
2752 
2753 static void sock_def_error_report(struct sock *sk)
2754 {
2755 	struct socket_wq *wq;
2756 
2757 	rcu_read_lock();
2758 	wq = rcu_dereference(sk->sk_wq);
2759 	if (skwq_has_sleeper(wq))
2760 		wake_up_interruptible_poll(&wq->wait, EPOLLERR);
2761 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2762 	rcu_read_unlock();
2763 }
2764 
2765 static void sock_def_readable(struct sock *sk)
2766 {
2767 	struct socket_wq *wq;
2768 
2769 	rcu_read_lock();
2770 	wq = rcu_dereference(sk->sk_wq);
2771 	if (skwq_has_sleeper(wq))
2772 		wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
2773 						EPOLLRDNORM | EPOLLRDBAND);
2774 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2775 	rcu_read_unlock();
2776 }
2777 
2778 static void sock_def_write_space(struct sock *sk)
2779 {
2780 	struct socket_wq *wq;
2781 
2782 	rcu_read_lock();
2783 
2784 	/* Do not wake up a writer until he can make "significant"
2785 	 * progress.  --DaveM
2786 	 */
2787 	if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2788 		wq = rcu_dereference(sk->sk_wq);
2789 		if (skwq_has_sleeper(wq))
2790 			wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
2791 						EPOLLWRNORM | EPOLLWRBAND);
2792 
2793 		/* Should agree with poll, otherwise some programs break */
2794 		if (sock_writeable(sk))
2795 			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2796 	}
2797 
2798 	rcu_read_unlock();
2799 }
2800 
2801 static void sock_def_destruct(struct sock *sk)
2802 {
2803 }
2804 
2805 void sk_send_sigurg(struct sock *sk)
2806 {
2807 	if (sk->sk_socket && sk->sk_socket->file)
2808 		if (send_sigurg(&sk->sk_socket->file->f_owner))
2809 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2810 }
2811 EXPORT_SYMBOL(sk_send_sigurg);
2812 
2813 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2814 		    unsigned long expires)
2815 {
2816 	if (!mod_timer(timer, expires))
2817 		sock_hold(sk);
2818 }
2819 EXPORT_SYMBOL(sk_reset_timer);
2820 
2821 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2822 {
2823 	if (del_timer(timer))
2824 		__sock_put(sk);
2825 }
2826 EXPORT_SYMBOL(sk_stop_timer);
2827 
2828 void sock_init_data(struct socket *sock, struct sock *sk)
2829 {
2830 	sk_init_common(sk);
2831 	sk->sk_send_head	=	NULL;
2832 
2833 	timer_setup(&sk->sk_timer, NULL, 0);
2834 
2835 	sk->sk_allocation	=	GFP_KERNEL;
2836 	sk->sk_rcvbuf		=	sysctl_rmem_default;
2837 	sk->sk_sndbuf		=	sysctl_wmem_default;
2838 	sk->sk_state		=	TCP_CLOSE;
2839 	sk_set_socket(sk, sock);
2840 
2841 	sock_set_flag(sk, SOCK_ZAPPED);
2842 
2843 	if (sock) {
2844 		sk->sk_type	=	sock->type;
2845 		RCU_INIT_POINTER(sk->sk_wq, sock->wq);
2846 		sock->sk	=	sk;
2847 		sk->sk_uid	=	SOCK_INODE(sock)->i_uid;
2848 	} else {
2849 		RCU_INIT_POINTER(sk->sk_wq, NULL);
2850 		sk->sk_uid	=	make_kuid(sock_net(sk)->user_ns, 0);
2851 	}
2852 
2853 	rwlock_init(&sk->sk_callback_lock);
2854 	if (sk->sk_kern_sock)
2855 		lockdep_set_class_and_name(
2856 			&sk->sk_callback_lock,
2857 			af_kern_callback_keys + sk->sk_family,
2858 			af_family_kern_clock_key_strings[sk->sk_family]);
2859 	else
2860 		lockdep_set_class_and_name(
2861 			&sk->sk_callback_lock,
2862 			af_callback_keys + sk->sk_family,
2863 			af_family_clock_key_strings[sk->sk_family]);
2864 
2865 	sk->sk_state_change	=	sock_def_wakeup;
2866 	sk->sk_data_ready	=	sock_def_readable;
2867 	sk->sk_write_space	=	sock_def_write_space;
2868 	sk->sk_error_report	=	sock_def_error_report;
2869 	sk->sk_destruct		=	sock_def_destruct;
2870 
2871 	sk->sk_frag.page	=	NULL;
2872 	sk->sk_frag.offset	=	0;
2873 	sk->sk_peek_off		=	-1;
2874 
2875 	sk->sk_peer_pid 	=	NULL;
2876 	sk->sk_peer_cred	=	NULL;
2877 	sk->sk_write_pending	=	0;
2878 	sk->sk_rcvlowat		=	1;
2879 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2880 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2881 
2882 	sk->sk_stamp = SK_DEFAULT_STAMP;
2883 #if BITS_PER_LONG==32
2884 	seqlock_init(&sk->sk_stamp_seq);
2885 #endif
2886 	atomic_set(&sk->sk_zckey, 0);
2887 
2888 #ifdef CONFIG_NET_RX_BUSY_POLL
2889 	sk->sk_napi_id		=	0;
2890 	sk->sk_ll_usec		=	sysctl_net_busy_read;
2891 #endif
2892 
2893 	sk->sk_max_pacing_rate = ~0UL;
2894 	sk->sk_pacing_rate = ~0UL;
2895 	sk->sk_pacing_shift = 10;
2896 	sk->sk_incoming_cpu = -1;
2897 
2898 	sk_rx_queue_clear(sk);
2899 	/*
2900 	 * Before updating sk_refcnt, we must commit prior changes to memory
2901 	 * (Documentation/RCU/rculist_nulls.txt for details)
2902 	 */
2903 	smp_wmb();
2904 	refcount_set(&sk->sk_refcnt, 1);
2905 	atomic_set(&sk->sk_drops, 0);
2906 }
2907 EXPORT_SYMBOL(sock_init_data);
2908 
2909 void lock_sock_nested(struct sock *sk, int subclass)
2910 {
2911 	might_sleep();
2912 	spin_lock_bh(&sk->sk_lock.slock);
2913 	if (sk->sk_lock.owned)
2914 		__lock_sock(sk);
2915 	sk->sk_lock.owned = 1;
2916 	spin_unlock(&sk->sk_lock.slock);
2917 	/*
2918 	 * The sk_lock has mutex_lock() semantics here:
2919 	 */
2920 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2921 	local_bh_enable();
2922 }
2923 EXPORT_SYMBOL(lock_sock_nested);
2924 
2925 void release_sock(struct sock *sk)
2926 {
2927 	spin_lock_bh(&sk->sk_lock.slock);
2928 	if (sk->sk_backlog.tail)
2929 		__release_sock(sk);
2930 
2931 	/* Warning : release_cb() might need to release sk ownership,
2932 	 * ie call sock_release_ownership(sk) before us.
2933 	 */
2934 	if (sk->sk_prot->release_cb)
2935 		sk->sk_prot->release_cb(sk);
2936 
2937 	sock_release_ownership(sk);
2938 	if (waitqueue_active(&sk->sk_lock.wq))
2939 		wake_up(&sk->sk_lock.wq);
2940 	spin_unlock_bh(&sk->sk_lock.slock);
2941 }
2942 EXPORT_SYMBOL(release_sock);
2943 
2944 /**
2945  * lock_sock_fast - fast version of lock_sock
2946  * @sk: socket
2947  *
2948  * This version should be used for very small section, where process wont block
2949  * return false if fast path is taken:
2950  *
2951  *   sk_lock.slock locked, owned = 0, BH disabled
2952  *
2953  * return true if slow path is taken:
2954  *
2955  *   sk_lock.slock unlocked, owned = 1, BH enabled
2956  */
2957 bool lock_sock_fast(struct sock *sk)
2958 {
2959 	might_sleep();
2960 	spin_lock_bh(&sk->sk_lock.slock);
2961 
2962 	if (!sk->sk_lock.owned)
2963 		/*
2964 		 * Note : We must disable BH
2965 		 */
2966 		return false;
2967 
2968 	__lock_sock(sk);
2969 	sk->sk_lock.owned = 1;
2970 	spin_unlock(&sk->sk_lock.slock);
2971 	/*
2972 	 * The sk_lock has mutex_lock() semantics here:
2973 	 */
2974 	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2975 	local_bh_enable();
2976 	return true;
2977 }
2978 EXPORT_SYMBOL(lock_sock_fast);
2979 
2980 int sock_gettstamp(struct socket *sock, void __user *userstamp,
2981 		   bool timeval, bool time32)
2982 {
2983 	struct sock *sk = sock->sk;
2984 	struct timespec64 ts;
2985 
2986 	sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2987 	ts = ktime_to_timespec64(sock_read_timestamp(sk));
2988 	if (ts.tv_sec == -1)
2989 		return -ENOENT;
2990 	if (ts.tv_sec == 0) {
2991 		ktime_t kt = ktime_get_real();
2992 		sock_write_timestamp(sk, kt);;
2993 		ts = ktime_to_timespec64(kt);
2994 	}
2995 
2996 	if (timeval)
2997 		ts.tv_nsec /= 1000;
2998 
2999 #ifdef CONFIG_COMPAT_32BIT_TIME
3000 	if (time32)
3001 		return put_old_timespec32(&ts, userstamp);
3002 #endif
3003 #ifdef CONFIG_SPARC64
3004 	/* beware of padding in sparc64 timeval */
3005 	if (timeval && !in_compat_syscall()) {
3006 		struct __kernel_old_timeval __user tv = {
3007 			.tv_sec = ts.tv_sec;
3008 			.tv_usec = ts.tv_nsec;
3009 		};
3010 		if (copy_to_user(userstamp, &tv, sizeof(tv))
3011 			return -EFAULT;
3012 		return 0;
3013 	}
3014 #endif
3015 	return put_timespec64(&ts, userstamp);
3016 }
3017 EXPORT_SYMBOL(sock_gettstamp);
3018 
3019 void sock_enable_timestamp(struct sock *sk, int flag)
3020 {
3021 	if (!sock_flag(sk, flag)) {
3022 		unsigned long previous_flags = sk->sk_flags;
3023 
3024 		sock_set_flag(sk, flag);
3025 		/*
3026 		 * we just set one of the two flags which require net
3027 		 * time stamping, but time stamping might have been on
3028 		 * already because of the other one
3029 		 */
3030 		if (sock_needs_netstamp(sk) &&
3031 		    !(previous_flags & SK_FLAGS_TIMESTAMP))
3032 			net_enable_timestamp();
3033 	}
3034 }
3035 
3036 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3037 		       int level, int type)
3038 {
3039 	struct sock_exterr_skb *serr;
3040 	struct sk_buff *skb;
3041 	int copied, err;
3042 
3043 	err = -EAGAIN;
3044 	skb = sock_dequeue_err_skb(sk);
3045 	if (skb == NULL)
3046 		goto out;
3047 
3048 	copied = skb->len;
3049 	if (copied > len) {
3050 		msg->msg_flags |= MSG_TRUNC;
3051 		copied = len;
3052 	}
3053 	err = skb_copy_datagram_msg(skb, 0, msg, copied);
3054 	if (err)
3055 		goto out_free_skb;
3056 
3057 	sock_recv_timestamp(msg, sk, skb);
3058 
3059 	serr = SKB_EXT_ERR(skb);
3060 	put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3061 
3062 	msg->msg_flags |= MSG_ERRQUEUE;
3063 	err = copied;
3064 
3065 out_free_skb:
3066 	kfree_skb(skb);
3067 out:
3068 	return err;
3069 }
3070 EXPORT_SYMBOL(sock_recv_errqueue);
3071 
3072 /*
3073  *	Get a socket option on an socket.
3074  *
3075  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
3076  *	asynchronous errors should be reported by getsockopt. We assume
3077  *	this means if you specify SO_ERROR (otherwise whats the point of it).
3078  */
3079 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3080 			   char __user *optval, int __user *optlen)
3081 {
3082 	struct sock *sk = sock->sk;
3083 
3084 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3085 }
3086 EXPORT_SYMBOL(sock_common_getsockopt);
3087 
3088 #ifdef CONFIG_COMPAT
3089 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
3090 				  char __user *optval, int __user *optlen)
3091 {
3092 	struct sock *sk = sock->sk;
3093 
3094 	if (sk->sk_prot->compat_getsockopt != NULL)
3095 		return sk->sk_prot->compat_getsockopt(sk, level, optname,
3096 						      optval, optlen);
3097 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3098 }
3099 EXPORT_SYMBOL(compat_sock_common_getsockopt);
3100 #endif
3101 
3102 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3103 			int flags)
3104 {
3105 	struct sock *sk = sock->sk;
3106 	int addr_len = 0;
3107 	int err;
3108 
3109 	err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
3110 				   flags & ~MSG_DONTWAIT, &addr_len);
3111 	if (err >= 0)
3112 		msg->msg_namelen = addr_len;
3113 	return err;
3114 }
3115 EXPORT_SYMBOL(sock_common_recvmsg);
3116 
3117 /*
3118  *	Set socket options on an inet socket.
3119  */
3120 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3121 			   char __user *optval, unsigned int optlen)
3122 {
3123 	struct sock *sk = sock->sk;
3124 
3125 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3126 }
3127 EXPORT_SYMBOL(sock_common_setsockopt);
3128 
3129 #ifdef CONFIG_COMPAT
3130 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
3131 				  char __user *optval, unsigned int optlen)
3132 {
3133 	struct sock *sk = sock->sk;
3134 
3135 	if (sk->sk_prot->compat_setsockopt != NULL)
3136 		return sk->sk_prot->compat_setsockopt(sk, level, optname,
3137 						      optval, optlen);
3138 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3139 }
3140 EXPORT_SYMBOL(compat_sock_common_setsockopt);
3141 #endif
3142 
3143 void sk_common_release(struct sock *sk)
3144 {
3145 	if (sk->sk_prot->destroy)
3146 		sk->sk_prot->destroy(sk);
3147 
3148 	/*
3149 	 * Observation: when sock_common_release is called, processes have
3150 	 * no access to socket. But net still has.
3151 	 * Step one, detach it from networking:
3152 	 *
3153 	 * A. Remove from hash tables.
3154 	 */
3155 
3156 	sk->sk_prot->unhash(sk);
3157 
3158 	/*
3159 	 * In this point socket cannot receive new packets, but it is possible
3160 	 * that some packets are in flight because some CPU runs receiver and
3161 	 * did hash table lookup before we unhashed socket. They will achieve
3162 	 * receive queue and will be purged by socket destructor.
3163 	 *
3164 	 * Also we still have packets pending on receive queue and probably,
3165 	 * our own packets waiting in device queues. sock_destroy will drain
3166 	 * receive queue, but transmitted packets will delay socket destruction
3167 	 * until the last reference will be released.
3168 	 */
3169 
3170 	sock_orphan(sk);
3171 
3172 	xfrm_sk_free_policy(sk);
3173 
3174 	sk_refcnt_debug_release(sk);
3175 
3176 	sock_put(sk);
3177 }
3178 EXPORT_SYMBOL(sk_common_release);
3179 
3180 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3181 {
3182 	memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3183 
3184 	mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3185 	mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
3186 	mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3187 	mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
3188 	mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3189 	mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
3190 	mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3191 	mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len;
3192 	mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3193 }
3194 
3195 #ifdef CONFIG_PROC_FS
3196 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
3197 struct prot_inuse {
3198 	int val[PROTO_INUSE_NR];
3199 };
3200 
3201 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3202 
3203 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3204 {
3205 	__this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
3206 }
3207 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3208 
3209 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3210 {
3211 	int cpu, idx = prot->inuse_idx;
3212 	int res = 0;
3213 
3214 	for_each_possible_cpu(cpu)
3215 		res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3216 
3217 	return res >= 0 ? res : 0;
3218 }
3219 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3220 
3221 static void sock_inuse_add(struct net *net, int val)
3222 {
3223 	this_cpu_add(*net->core.sock_inuse, val);
3224 }
3225 
3226 int sock_inuse_get(struct net *net)
3227 {
3228 	int cpu, res = 0;
3229 
3230 	for_each_possible_cpu(cpu)
3231 		res += *per_cpu_ptr(net->core.sock_inuse, cpu);
3232 
3233 	return res;
3234 }
3235 
3236 EXPORT_SYMBOL_GPL(sock_inuse_get);
3237 
3238 static int __net_init sock_inuse_init_net(struct net *net)
3239 {
3240 	net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3241 	if (net->core.prot_inuse == NULL)
3242 		return -ENOMEM;
3243 
3244 	net->core.sock_inuse = alloc_percpu(int);
3245 	if (net->core.sock_inuse == NULL)
3246 		goto out;
3247 
3248 	return 0;
3249 
3250 out:
3251 	free_percpu(net->core.prot_inuse);
3252 	return -ENOMEM;
3253 }
3254 
3255 static void __net_exit sock_inuse_exit_net(struct net *net)
3256 {
3257 	free_percpu(net->core.prot_inuse);
3258 	free_percpu(net->core.sock_inuse);
3259 }
3260 
3261 static struct pernet_operations net_inuse_ops = {
3262 	.init = sock_inuse_init_net,
3263 	.exit = sock_inuse_exit_net,
3264 };
3265 
3266 static __init int net_inuse_init(void)
3267 {
3268 	if (register_pernet_subsys(&net_inuse_ops))
3269 		panic("Cannot initialize net inuse counters");
3270 
3271 	return 0;
3272 }
3273 
3274 core_initcall(net_inuse_init);
3275 
3276 static void assign_proto_idx(struct proto *prot)
3277 {
3278 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3279 
3280 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3281 		pr_err("PROTO_INUSE_NR exhausted\n");
3282 		return;
3283 	}
3284 
3285 	set_bit(prot->inuse_idx, proto_inuse_idx);
3286 }
3287 
3288 static void release_proto_idx(struct proto *prot)
3289 {
3290 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3291 		clear_bit(prot->inuse_idx, proto_inuse_idx);
3292 }
3293 #else
3294 static inline void assign_proto_idx(struct proto *prot)
3295 {
3296 }
3297 
3298 static inline void release_proto_idx(struct proto *prot)
3299 {
3300 }
3301 
3302 static void sock_inuse_add(struct net *net, int val)
3303 {
3304 }
3305 #endif
3306 
3307 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3308 {
3309 	if (!rsk_prot)
3310 		return;
3311 	kfree(rsk_prot->slab_name);
3312 	rsk_prot->slab_name = NULL;
3313 	kmem_cache_destroy(rsk_prot->slab);
3314 	rsk_prot->slab = NULL;
3315 }
3316 
3317 static int req_prot_init(const struct proto *prot)
3318 {
3319 	struct request_sock_ops *rsk_prot = prot->rsk_prot;
3320 
3321 	if (!rsk_prot)
3322 		return 0;
3323 
3324 	rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3325 					prot->name);
3326 	if (!rsk_prot->slab_name)
3327 		return -ENOMEM;
3328 
3329 	rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3330 					   rsk_prot->obj_size, 0,
3331 					   SLAB_ACCOUNT | prot->slab_flags,
3332 					   NULL);
3333 
3334 	if (!rsk_prot->slab) {
3335 		pr_crit("%s: Can't create request sock SLAB cache!\n",
3336 			prot->name);
3337 		return -ENOMEM;
3338 	}
3339 	return 0;
3340 }
3341 
3342 int proto_register(struct proto *prot, int alloc_slab)
3343 {
3344 	if (alloc_slab) {
3345 		prot->slab = kmem_cache_create_usercopy(prot->name,
3346 					prot->obj_size, 0,
3347 					SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3348 					prot->slab_flags,
3349 					prot->useroffset, prot->usersize,
3350 					NULL);
3351 
3352 		if (prot->slab == NULL) {
3353 			pr_crit("%s: Can't create sock SLAB cache!\n",
3354 				prot->name);
3355 			goto out;
3356 		}
3357 
3358 		if (req_prot_init(prot))
3359 			goto out_free_request_sock_slab;
3360 
3361 		if (prot->twsk_prot != NULL) {
3362 			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
3363 
3364 			if (prot->twsk_prot->twsk_slab_name == NULL)
3365 				goto out_free_request_sock_slab;
3366 
3367 			prot->twsk_prot->twsk_slab =
3368 				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
3369 						  prot->twsk_prot->twsk_obj_size,
3370 						  0,
3371 						  SLAB_ACCOUNT |
3372 						  prot->slab_flags,
3373 						  NULL);
3374 			if (prot->twsk_prot->twsk_slab == NULL)
3375 				goto out_free_timewait_sock_slab_name;
3376 		}
3377 	}
3378 
3379 	mutex_lock(&proto_list_mutex);
3380 	list_add(&prot->node, &proto_list);
3381 	assign_proto_idx(prot);
3382 	mutex_unlock(&proto_list_mutex);
3383 	return 0;
3384 
3385 out_free_timewait_sock_slab_name:
3386 	kfree(prot->twsk_prot->twsk_slab_name);
3387 out_free_request_sock_slab:
3388 	req_prot_cleanup(prot->rsk_prot);
3389 
3390 	kmem_cache_destroy(prot->slab);
3391 	prot->slab = NULL;
3392 out:
3393 	return -ENOBUFS;
3394 }
3395 EXPORT_SYMBOL(proto_register);
3396 
3397 void proto_unregister(struct proto *prot)
3398 {
3399 	mutex_lock(&proto_list_mutex);
3400 	release_proto_idx(prot);
3401 	list_del(&prot->node);
3402 	mutex_unlock(&proto_list_mutex);
3403 
3404 	kmem_cache_destroy(prot->slab);
3405 	prot->slab = NULL;
3406 
3407 	req_prot_cleanup(prot->rsk_prot);
3408 
3409 	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
3410 		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
3411 		kfree(prot->twsk_prot->twsk_slab_name);
3412 		prot->twsk_prot->twsk_slab = NULL;
3413 	}
3414 }
3415 EXPORT_SYMBOL(proto_unregister);
3416 
3417 int sock_load_diag_module(int family, int protocol)
3418 {
3419 	if (!protocol) {
3420 		if (!sock_is_registered(family))
3421 			return -ENOENT;
3422 
3423 		return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3424 				      NETLINK_SOCK_DIAG, family);
3425 	}
3426 
3427 #ifdef CONFIG_INET
3428 	if (family == AF_INET &&
3429 	    protocol != IPPROTO_RAW &&
3430 	    !rcu_access_pointer(inet_protos[protocol]))
3431 		return -ENOENT;
3432 #endif
3433 
3434 	return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3435 			      NETLINK_SOCK_DIAG, family, protocol);
3436 }
3437 EXPORT_SYMBOL(sock_load_diag_module);
3438 
3439 #ifdef CONFIG_PROC_FS
3440 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3441 	__acquires(proto_list_mutex)
3442 {
3443 	mutex_lock(&proto_list_mutex);
3444 	return seq_list_start_head(&proto_list, *pos);
3445 }
3446 
3447 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3448 {
3449 	return seq_list_next(v, &proto_list, pos);
3450 }
3451 
3452 static void proto_seq_stop(struct seq_file *seq, void *v)
3453 	__releases(proto_list_mutex)
3454 {
3455 	mutex_unlock(&proto_list_mutex);
3456 }
3457 
3458 static char proto_method_implemented(const void *method)
3459 {
3460 	return method == NULL ? 'n' : 'y';
3461 }
3462 static long sock_prot_memory_allocated(struct proto *proto)
3463 {
3464 	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3465 }
3466 
3467 static char *sock_prot_memory_pressure(struct proto *proto)
3468 {
3469 	return proto->memory_pressure != NULL ?
3470 	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3471 }
3472 
3473 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3474 {
3475 
3476 	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
3477 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3478 		   proto->name,
3479 		   proto->obj_size,
3480 		   sock_prot_inuse_get(seq_file_net(seq), proto),
3481 		   sock_prot_memory_allocated(proto),
3482 		   sock_prot_memory_pressure(proto),
3483 		   proto->max_header,
3484 		   proto->slab == NULL ? "no" : "yes",
3485 		   module_name(proto->owner),
3486 		   proto_method_implemented(proto->close),
3487 		   proto_method_implemented(proto->connect),
3488 		   proto_method_implemented(proto->disconnect),
3489 		   proto_method_implemented(proto->accept),
3490 		   proto_method_implemented(proto->ioctl),
3491 		   proto_method_implemented(proto->init),
3492 		   proto_method_implemented(proto->destroy),
3493 		   proto_method_implemented(proto->shutdown),
3494 		   proto_method_implemented(proto->setsockopt),
3495 		   proto_method_implemented(proto->getsockopt),
3496 		   proto_method_implemented(proto->sendmsg),
3497 		   proto_method_implemented(proto->recvmsg),
3498 		   proto_method_implemented(proto->sendpage),
3499 		   proto_method_implemented(proto->bind),
3500 		   proto_method_implemented(proto->backlog_rcv),
3501 		   proto_method_implemented(proto->hash),
3502 		   proto_method_implemented(proto->unhash),
3503 		   proto_method_implemented(proto->get_port),
3504 		   proto_method_implemented(proto->enter_memory_pressure));
3505 }
3506 
3507 static int proto_seq_show(struct seq_file *seq, void *v)
3508 {
3509 	if (v == &proto_list)
3510 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3511 			   "protocol",
3512 			   "size",
3513 			   "sockets",
3514 			   "memory",
3515 			   "press",
3516 			   "maxhdr",
3517 			   "slab",
3518 			   "module",
3519 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3520 	else
3521 		proto_seq_printf(seq, list_entry(v, struct proto, node));
3522 	return 0;
3523 }
3524 
3525 static const struct seq_operations proto_seq_ops = {
3526 	.start  = proto_seq_start,
3527 	.next   = proto_seq_next,
3528 	.stop   = proto_seq_stop,
3529 	.show   = proto_seq_show,
3530 };
3531 
3532 static __net_init int proto_init_net(struct net *net)
3533 {
3534 	if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
3535 			sizeof(struct seq_net_private)))
3536 		return -ENOMEM;
3537 
3538 	return 0;
3539 }
3540 
3541 static __net_exit void proto_exit_net(struct net *net)
3542 {
3543 	remove_proc_entry("protocols", net->proc_net);
3544 }
3545 
3546 
3547 static __net_initdata struct pernet_operations proto_net_ops = {
3548 	.init = proto_init_net,
3549 	.exit = proto_exit_net,
3550 };
3551 
3552 static int __init proto_init(void)
3553 {
3554 	return register_pernet_subsys(&proto_net_ops);
3555 }
3556 
3557 subsys_initcall(proto_init);
3558 
3559 #endif /* PROC_FS */
3560 
3561 #ifdef CONFIG_NET_RX_BUSY_POLL
3562 bool sk_busy_loop_end(void *p, unsigned long start_time)
3563 {
3564 	struct sock *sk = p;
3565 
3566 	return !skb_queue_empty(&sk->sk_receive_queue) ||
3567 	       sk_busy_loop_timeout(sk, start_time);
3568 }
3569 EXPORT_SYMBOL(sk_busy_loop_end);
3570 #endif /* CONFIG_NET_RX_BUSY_POLL */
3571