sock.c revision 1485348d2424e1131ea42efc033cbd9366462b01
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 <linux/capability.h>
95#include <linux/errno.h>
96#include <linux/types.h>
97#include <linux/socket.h>
98#include <linux/in.h>
99#include <linux/kernel.h>
100#include <linux/module.h>
101#include <linux/proc_fs.h>
102#include <linux/seq_file.h>
103#include <linux/sched.h>
104#include <linux/timer.h>
105#include <linux/string.h>
106#include <linux/sockios.h>
107#include <linux/net.h>
108#include <linux/mm.h>
109#include <linux/slab.h>
110#include <linux/interrupt.h>
111#include <linux/poll.h>
112#include <linux/tcp.h>
113#include <linux/init.h>
114#include <linux/highmem.h>
115#include <linux/user_namespace.h>
116#include <linux/static_key.h>
117#include <linux/memcontrol.h>
118#include <linux/prefetch.h>
119
120#include <asm/uaccess.h>
121
122#include <linux/netdevice.h>
123#include <net/protocol.h>
124#include <linux/skbuff.h>
125#include <net/net_namespace.h>
126#include <net/request_sock.h>
127#include <net/sock.h>
128#include <linux/net_tstamp.h>
129#include <net/xfrm.h>
130#include <linux/ipsec.h>
131#include <net/cls_cgroup.h>
132#include <net/netprio_cgroup.h>
133
134#include <linux/filter.h>
135
136#include <trace/events/sock.h>
137
138#ifdef CONFIG_INET
139#include <net/tcp.h>
140#endif
141
142static DEFINE_MUTEX(proto_list_mutex);
143static LIST_HEAD(proto_list);
144
145#ifdef CONFIG_MEMCG_KMEM
146int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
147{
148	struct proto *proto;
149	int ret = 0;
150
151	mutex_lock(&proto_list_mutex);
152	list_for_each_entry(proto, &proto_list, node) {
153		if (proto->init_cgroup) {
154			ret = proto->init_cgroup(memcg, ss);
155			if (ret)
156				goto out;
157		}
158	}
159
160	mutex_unlock(&proto_list_mutex);
161	return ret;
162out:
163	list_for_each_entry_continue_reverse(proto, &proto_list, node)
164		if (proto->destroy_cgroup)
165			proto->destroy_cgroup(memcg);
166	mutex_unlock(&proto_list_mutex);
167	return ret;
168}
169
170void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
171{
172	struct proto *proto;
173
174	mutex_lock(&proto_list_mutex);
175	list_for_each_entry_reverse(proto, &proto_list, node)
176		if (proto->destroy_cgroup)
177			proto->destroy_cgroup(memcg);
178	mutex_unlock(&proto_list_mutex);
179}
180#endif
181
182/*
183 * Each address family might have different locking rules, so we have
184 * one slock key per address family:
185 */
186static struct lock_class_key af_family_keys[AF_MAX];
187static struct lock_class_key af_family_slock_keys[AF_MAX];
188
189struct static_key memcg_socket_limit_enabled;
190EXPORT_SYMBOL(memcg_socket_limit_enabled);
191
192/*
193 * Make lock validator output more readable. (we pre-construct these
194 * strings build-time, so that runtime initialization of socket
195 * locks is fast):
196 */
197static const char *const af_family_key_strings[AF_MAX+1] = {
198  "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX"     , "sk_lock-AF_INET"     ,
199  "sk_lock-AF_AX25"  , "sk_lock-AF_IPX"      , "sk_lock-AF_APPLETALK",
200  "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE"   , "sk_lock-AF_ATMPVC"   ,
201  "sk_lock-AF_X25"   , "sk_lock-AF_INET6"    , "sk_lock-AF_ROSE"     ,
202  "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI"  , "sk_lock-AF_SECURITY" ,
203  "sk_lock-AF_KEY"   , "sk_lock-AF_NETLINK"  , "sk_lock-AF_PACKET"   ,
204  "sk_lock-AF_ASH"   , "sk_lock-AF_ECONET"   , "sk_lock-AF_ATMSVC"   ,
205  "sk_lock-AF_RDS"   , "sk_lock-AF_SNA"      , "sk_lock-AF_IRDA"     ,
206  "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE"  , "sk_lock-AF_LLC"      ,
207  "sk_lock-27"       , "sk_lock-28"          , "sk_lock-AF_CAN"      ,
208  "sk_lock-AF_TIPC"  , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV"        ,
209  "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN"     , "sk_lock-AF_PHONET"   ,
210  "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG"      ,
211  "sk_lock-AF_NFC"   , "sk_lock-AF_MAX"
212};
213static const char *const af_family_slock_key_strings[AF_MAX+1] = {
214  "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
215  "slock-AF_AX25"  , "slock-AF_IPX"      , "slock-AF_APPLETALK",
216  "slock-AF_NETROM", "slock-AF_BRIDGE"   , "slock-AF_ATMPVC"   ,
217  "slock-AF_X25"   , "slock-AF_INET6"    , "slock-AF_ROSE"     ,
218  "slock-AF_DECnet", "slock-AF_NETBEUI"  , "slock-AF_SECURITY" ,
219  "slock-AF_KEY"   , "slock-AF_NETLINK"  , "slock-AF_PACKET"   ,
220  "slock-AF_ASH"   , "slock-AF_ECONET"   , "slock-AF_ATMSVC"   ,
221  "slock-AF_RDS"   , "slock-AF_SNA"      , "slock-AF_IRDA"     ,
222  "slock-AF_PPPOX" , "slock-AF_WANPIPE"  , "slock-AF_LLC"      ,
223  "slock-27"       , "slock-28"          , "slock-AF_CAN"      ,
224  "slock-AF_TIPC"  , "slock-AF_BLUETOOTH", "slock-AF_IUCV"     ,
225  "slock-AF_RXRPC" , "slock-AF_ISDN"     , "slock-AF_PHONET"   ,
226  "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG"      ,
227  "slock-AF_NFC"   , "slock-AF_MAX"
228};
229static const char *const af_family_clock_key_strings[AF_MAX+1] = {
230  "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
231  "clock-AF_AX25"  , "clock-AF_IPX"      , "clock-AF_APPLETALK",
232  "clock-AF_NETROM", "clock-AF_BRIDGE"   , "clock-AF_ATMPVC"   ,
233  "clock-AF_X25"   , "clock-AF_INET6"    , "clock-AF_ROSE"     ,
234  "clock-AF_DECnet", "clock-AF_NETBEUI"  , "clock-AF_SECURITY" ,
235  "clock-AF_KEY"   , "clock-AF_NETLINK"  , "clock-AF_PACKET"   ,
236  "clock-AF_ASH"   , "clock-AF_ECONET"   , "clock-AF_ATMSVC"   ,
237  "clock-AF_RDS"   , "clock-AF_SNA"      , "clock-AF_IRDA"     ,
238  "clock-AF_PPPOX" , "clock-AF_WANPIPE"  , "clock-AF_LLC"      ,
239  "clock-27"       , "clock-28"          , "clock-AF_CAN"      ,
240  "clock-AF_TIPC"  , "clock-AF_BLUETOOTH", "clock-AF_IUCV"     ,
241  "clock-AF_RXRPC" , "clock-AF_ISDN"     , "clock-AF_PHONET"   ,
242  "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG"      ,
243  "clock-AF_NFC"   , "clock-AF_MAX"
244};
245
246/*
247 * sk_callback_lock locking rules are per-address-family,
248 * so split the lock classes by using a per-AF key:
249 */
250static struct lock_class_key af_callback_keys[AF_MAX];
251
252/* Take into consideration the size of the struct sk_buff overhead in the
253 * determination of these values, since that is non-constant across
254 * platforms.  This makes socket queueing behavior and performance
255 * not depend upon such differences.
256 */
257#define _SK_MEM_PACKETS		256
258#define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
259#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
260#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
261
262/* Run time adjustable parameters. */
263__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
264EXPORT_SYMBOL(sysctl_wmem_max);
265__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
266EXPORT_SYMBOL(sysctl_rmem_max);
267__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
268__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
269
270/* Maximal space eaten by iovec or ancillary data plus some space */
271int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
272EXPORT_SYMBOL(sysctl_optmem_max);
273
274struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
275EXPORT_SYMBOL_GPL(memalloc_socks);
276
277/**
278 * sk_set_memalloc - sets %SOCK_MEMALLOC
279 * @sk: socket to set it on
280 *
281 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
282 * It's the responsibility of the admin to adjust min_free_kbytes
283 * to meet the requirements
284 */
285void sk_set_memalloc(struct sock *sk)
286{
287	sock_set_flag(sk, SOCK_MEMALLOC);
288	sk->sk_allocation |= __GFP_MEMALLOC;
289	static_key_slow_inc(&memalloc_socks);
290}
291EXPORT_SYMBOL_GPL(sk_set_memalloc);
292
293void sk_clear_memalloc(struct sock *sk)
294{
295	sock_reset_flag(sk, SOCK_MEMALLOC);
296	sk->sk_allocation &= ~__GFP_MEMALLOC;
297	static_key_slow_dec(&memalloc_socks);
298
299	/*
300	 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
301	 * progress of swapping. However, if SOCK_MEMALLOC is cleared while
302	 * it has rmem allocations there is a risk that the user of the
303	 * socket cannot make forward progress due to exceeding the rmem
304	 * limits. By rights, sk_clear_memalloc() should only be called
305	 * on sockets being torn down but warn and reset the accounting if
306	 * that assumption breaks.
307	 */
308	if (WARN_ON(sk->sk_forward_alloc))
309		sk_mem_reclaim(sk);
310}
311EXPORT_SYMBOL_GPL(sk_clear_memalloc);
312
313int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
314{
315	int ret;
316	unsigned long pflags = current->flags;
317
318	/* these should have been dropped before queueing */
319	BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
320
321	current->flags |= PF_MEMALLOC;
322	ret = sk->sk_backlog_rcv(sk, skb);
323	tsk_restore_flags(current, pflags, PF_MEMALLOC);
324
325	return ret;
326}
327EXPORT_SYMBOL(__sk_backlog_rcv);
328
329#if defined(CONFIG_CGROUPS)
330#if !defined(CONFIG_NET_CLS_CGROUP)
331int net_cls_subsys_id = -1;
332EXPORT_SYMBOL_GPL(net_cls_subsys_id);
333#endif
334#if !defined(CONFIG_NETPRIO_CGROUP)
335int net_prio_subsys_id = -1;
336EXPORT_SYMBOL_GPL(net_prio_subsys_id);
337#endif
338#endif
339
340static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
341{
342	struct timeval tv;
343
344	if (optlen < sizeof(tv))
345		return -EINVAL;
346	if (copy_from_user(&tv, optval, sizeof(tv)))
347		return -EFAULT;
348	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
349		return -EDOM;
350
351	if (tv.tv_sec < 0) {
352		static int warned __read_mostly;
353
354		*timeo_p = 0;
355		if (warned < 10 && net_ratelimit()) {
356			warned++;
357			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
358				__func__, current->comm, task_pid_nr(current));
359		}
360		return 0;
361	}
362	*timeo_p = MAX_SCHEDULE_TIMEOUT;
363	if (tv.tv_sec == 0 && tv.tv_usec == 0)
364		return 0;
365	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
366		*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
367	return 0;
368}
369
370static void sock_warn_obsolete_bsdism(const char *name)
371{
372	static int warned;
373	static char warncomm[TASK_COMM_LEN];
374	if (strcmp(warncomm, current->comm) && warned < 5) {
375		strcpy(warncomm,  current->comm);
376		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
377			warncomm, name);
378		warned++;
379	}
380}
381
382#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
383
384static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
385{
386	if (sk->sk_flags & flags) {
387		sk->sk_flags &= ~flags;
388		if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP))
389			net_disable_timestamp();
390	}
391}
392
393
394int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
395{
396	int err;
397	int skb_len;
398	unsigned long flags;
399	struct sk_buff_head *list = &sk->sk_receive_queue;
400
401	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
402		atomic_inc(&sk->sk_drops);
403		trace_sock_rcvqueue_full(sk, skb);
404		return -ENOMEM;
405	}
406
407	err = sk_filter(sk, skb);
408	if (err)
409		return err;
410
411	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
412		atomic_inc(&sk->sk_drops);
413		return -ENOBUFS;
414	}
415
416	skb->dev = NULL;
417	skb_set_owner_r(skb, sk);
418
419	/* Cache the SKB length before we tack it onto the receive
420	 * queue.  Once it is added it no longer belongs to us and
421	 * may be freed by other threads of control pulling packets
422	 * from the queue.
423	 */
424	skb_len = skb->len;
425
426	/* we escape from rcu protected region, make sure we dont leak
427	 * a norefcounted dst
428	 */
429	skb_dst_force(skb);
430
431	spin_lock_irqsave(&list->lock, flags);
432	skb->dropcount = atomic_read(&sk->sk_drops);
433	__skb_queue_tail(list, skb);
434	spin_unlock_irqrestore(&list->lock, flags);
435
436	if (!sock_flag(sk, SOCK_DEAD))
437		sk->sk_data_ready(sk, skb_len);
438	return 0;
439}
440EXPORT_SYMBOL(sock_queue_rcv_skb);
441
442int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
443{
444	int rc = NET_RX_SUCCESS;
445
446	if (sk_filter(sk, skb))
447		goto discard_and_relse;
448
449	skb->dev = NULL;
450
451	if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) {
452		atomic_inc(&sk->sk_drops);
453		goto discard_and_relse;
454	}
455	if (nested)
456		bh_lock_sock_nested(sk);
457	else
458		bh_lock_sock(sk);
459	if (!sock_owned_by_user(sk)) {
460		/*
461		 * trylock + unlock semantics:
462		 */
463		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
464
465		rc = sk_backlog_rcv(sk, skb);
466
467		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
468	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
469		bh_unlock_sock(sk);
470		atomic_inc(&sk->sk_drops);
471		goto discard_and_relse;
472	}
473
474	bh_unlock_sock(sk);
475out:
476	sock_put(sk);
477	return rc;
478discard_and_relse:
479	kfree_skb(skb);
480	goto out;
481}
482EXPORT_SYMBOL(sk_receive_skb);
483
484void sk_reset_txq(struct sock *sk)
485{
486	sk_tx_queue_clear(sk);
487}
488EXPORT_SYMBOL(sk_reset_txq);
489
490struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
491{
492	struct dst_entry *dst = __sk_dst_get(sk);
493
494	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
495		sk_tx_queue_clear(sk);
496		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
497		dst_release(dst);
498		return NULL;
499	}
500
501	return dst;
502}
503EXPORT_SYMBOL(__sk_dst_check);
504
505struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
506{
507	struct dst_entry *dst = sk_dst_get(sk);
508
509	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
510		sk_dst_reset(sk);
511		dst_release(dst);
512		return NULL;
513	}
514
515	return dst;
516}
517EXPORT_SYMBOL(sk_dst_check);
518
519static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
520{
521	int ret = -ENOPROTOOPT;
522#ifdef CONFIG_NETDEVICES
523	struct net *net = sock_net(sk);
524	char devname[IFNAMSIZ];
525	int index;
526
527	/* Sorry... */
528	ret = -EPERM;
529	if (!capable(CAP_NET_RAW))
530		goto out;
531
532	ret = -EINVAL;
533	if (optlen < 0)
534		goto out;
535
536	/* Bind this socket to a particular device like "eth0",
537	 * as specified in the passed interface name. If the
538	 * name is "" or the option length is zero the socket
539	 * is not bound.
540	 */
541	if (optlen > IFNAMSIZ - 1)
542		optlen = IFNAMSIZ - 1;
543	memset(devname, 0, sizeof(devname));
544
545	ret = -EFAULT;
546	if (copy_from_user(devname, optval, optlen))
547		goto out;
548
549	index = 0;
550	if (devname[0] != '\0') {
551		struct net_device *dev;
552
553		rcu_read_lock();
554		dev = dev_get_by_name_rcu(net, devname);
555		if (dev)
556			index = dev->ifindex;
557		rcu_read_unlock();
558		ret = -ENODEV;
559		if (!dev)
560			goto out;
561	}
562
563	lock_sock(sk);
564	sk->sk_bound_dev_if = index;
565	sk_dst_reset(sk);
566	release_sock(sk);
567
568	ret = 0;
569
570out:
571#endif
572
573	return ret;
574}
575
576static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
577{
578	if (valbool)
579		sock_set_flag(sk, bit);
580	else
581		sock_reset_flag(sk, bit);
582}
583
584/*
585 *	This is meant for all protocols to use and covers goings on
586 *	at the socket level. Everything here is generic.
587 */
588
589int sock_setsockopt(struct socket *sock, int level, int optname,
590		    char __user *optval, unsigned int optlen)
591{
592	struct sock *sk = sock->sk;
593	int val;
594	int valbool;
595	struct linger ling;
596	int ret = 0;
597
598	/*
599	 *	Options without arguments
600	 */
601
602	if (optname == SO_BINDTODEVICE)
603		return sock_bindtodevice(sk, optval, optlen);
604
605	if (optlen < sizeof(int))
606		return -EINVAL;
607
608	if (get_user(val, (int __user *)optval))
609		return -EFAULT;
610
611	valbool = val ? 1 : 0;
612
613	lock_sock(sk);
614
615	switch (optname) {
616	case SO_DEBUG:
617		if (val && !capable(CAP_NET_ADMIN))
618			ret = -EACCES;
619		else
620			sock_valbool_flag(sk, SOCK_DBG, valbool);
621		break;
622	case SO_REUSEADDR:
623		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
624		break;
625	case SO_TYPE:
626	case SO_PROTOCOL:
627	case SO_DOMAIN:
628	case SO_ERROR:
629		ret = -ENOPROTOOPT;
630		break;
631	case SO_DONTROUTE:
632		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
633		break;
634	case SO_BROADCAST:
635		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
636		break;
637	case SO_SNDBUF:
638		/* Don't error on this BSD doesn't and if you think
639		 * about it this is right. Otherwise apps have to
640		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
641		 * are treated in BSD as hints
642		 */
643		val = min_t(u32, val, sysctl_wmem_max);
644set_sndbuf:
645		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
646		sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
647		/* Wake up sending tasks if we upped the value. */
648		sk->sk_write_space(sk);
649		break;
650
651	case SO_SNDBUFFORCE:
652		if (!capable(CAP_NET_ADMIN)) {
653			ret = -EPERM;
654			break;
655		}
656		goto set_sndbuf;
657
658	case SO_RCVBUF:
659		/* Don't error on this BSD doesn't and if you think
660		 * about it this is right. Otherwise apps have to
661		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
662		 * are treated in BSD as hints
663		 */
664		val = min_t(u32, val, sysctl_rmem_max);
665set_rcvbuf:
666		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
667		/*
668		 * We double it on the way in to account for
669		 * "struct sk_buff" etc. overhead.   Applications
670		 * assume that the SO_RCVBUF setting they make will
671		 * allow that much actual data to be received on that
672		 * socket.
673		 *
674		 * Applications are unaware that "struct sk_buff" and
675		 * other overheads allocate from the receive buffer
676		 * during socket buffer allocation.
677		 *
678		 * And after considering the possible alternatives,
679		 * returning the value we actually used in getsockopt
680		 * is the most desirable behavior.
681		 */
682		sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
683		break;
684
685	case SO_RCVBUFFORCE:
686		if (!capable(CAP_NET_ADMIN)) {
687			ret = -EPERM;
688			break;
689		}
690		goto set_rcvbuf;
691
692	case SO_KEEPALIVE:
693#ifdef CONFIG_INET
694		if (sk->sk_protocol == IPPROTO_TCP)
695			tcp_set_keepalive(sk, valbool);
696#endif
697		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
698		break;
699
700	case SO_OOBINLINE:
701		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
702		break;
703
704	case SO_NO_CHECK:
705		sk->sk_no_check = valbool;
706		break;
707
708	case SO_PRIORITY:
709		if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
710			sk->sk_priority = val;
711		else
712			ret = -EPERM;
713		break;
714
715	case SO_LINGER:
716		if (optlen < sizeof(ling)) {
717			ret = -EINVAL;	/* 1003.1g */
718			break;
719		}
720		if (copy_from_user(&ling, optval, sizeof(ling))) {
721			ret = -EFAULT;
722			break;
723		}
724		if (!ling.l_onoff)
725			sock_reset_flag(sk, SOCK_LINGER);
726		else {
727#if (BITS_PER_LONG == 32)
728			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
729				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
730			else
731#endif
732				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
733			sock_set_flag(sk, SOCK_LINGER);
734		}
735		break;
736
737	case SO_BSDCOMPAT:
738		sock_warn_obsolete_bsdism("setsockopt");
739		break;
740
741	case SO_PASSCRED:
742		if (valbool)
743			set_bit(SOCK_PASSCRED, &sock->flags);
744		else
745			clear_bit(SOCK_PASSCRED, &sock->flags);
746		break;
747
748	case SO_TIMESTAMP:
749	case SO_TIMESTAMPNS:
750		if (valbool)  {
751			if (optname == SO_TIMESTAMP)
752				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
753			else
754				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
755			sock_set_flag(sk, SOCK_RCVTSTAMP);
756			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
757		} else {
758			sock_reset_flag(sk, SOCK_RCVTSTAMP);
759			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
760		}
761		break;
762
763	case SO_TIMESTAMPING:
764		if (val & ~SOF_TIMESTAMPING_MASK) {
765			ret = -EINVAL;
766			break;
767		}
768		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE,
769				  val & SOF_TIMESTAMPING_TX_HARDWARE);
770		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE,
771				  val & SOF_TIMESTAMPING_TX_SOFTWARE);
772		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE,
773				  val & SOF_TIMESTAMPING_RX_HARDWARE);
774		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
775			sock_enable_timestamp(sk,
776					      SOCK_TIMESTAMPING_RX_SOFTWARE);
777		else
778			sock_disable_timestamp(sk,
779					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
780		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE,
781				  val & SOF_TIMESTAMPING_SOFTWARE);
782		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE,
783				  val & SOF_TIMESTAMPING_SYS_HARDWARE);
784		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE,
785				  val & SOF_TIMESTAMPING_RAW_HARDWARE);
786		break;
787
788	case SO_RCVLOWAT:
789		if (val < 0)
790			val = INT_MAX;
791		sk->sk_rcvlowat = val ? : 1;
792		break;
793
794	case SO_RCVTIMEO:
795		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
796		break;
797
798	case SO_SNDTIMEO:
799		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
800		break;
801
802	case SO_ATTACH_FILTER:
803		ret = -EINVAL;
804		if (optlen == sizeof(struct sock_fprog)) {
805			struct sock_fprog fprog;
806
807			ret = -EFAULT;
808			if (copy_from_user(&fprog, optval, sizeof(fprog)))
809				break;
810
811			ret = sk_attach_filter(&fprog, sk);
812		}
813		break;
814
815	case SO_DETACH_FILTER:
816		ret = sk_detach_filter(sk);
817		break;
818
819	case SO_PASSSEC:
820		if (valbool)
821			set_bit(SOCK_PASSSEC, &sock->flags);
822		else
823			clear_bit(SOCK_PASSSEC, &sock->flags);
824		break;
825	case SO_MARK:
826		if (!capable(CAP_NET_ADMIN))
827			ret = -EPERM;
828		else
829			sk->sk_mark = val;
830		break;
831
832		/* We implement the SO_SNDLOWAT etc to
833		   not be settable (1003.1g 5.3) */
834	case SO_RXQ_OVFL:
835		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
836		break;
837
838	case SO_WIFI_STATUS:
839		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
840		break;
841
842	case SO_PEEK_OFF:
843		if (sock->ops->set_peek_off)
844			sock->ops->set_peek_off(sk, val);
845		else
846			ret = -EOPNOTSUPP;
847		break;
848
849	case SO_NOFCS:
850		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
851		break;
852
853	default:
854		ret = -ENOPROTOOPT;
855		break;
856	}
857	release_sock(sk);
858	return ret;
859}
860EXPORT_SYMBOL(sock_setsockopt);
861
862
863void cred_to_ucred(struct pid *pid, const struct cred *cred,
864		   struct ucred *ucred)
865{
866	ucred->pid = pid_vnr(pid);
867	ucred->uid = ucred->gid = -1;
868	if (cred) {
869		struct user_namespace *current_ns = current_user_ns();
870
871		ucred->uid = from_kuid(current_ns, cred->euid);
872		ucred->gid = from_kgid(current_ns, cred->egid);
873	}
874}
875EXPORT_SYMBOL_GPL(cred_to_ucred);
876
877int sock_getsockopt(struct socket *sock, int level, int optname,
878		    char __user *optval, int __user *optlen)
879{
880	struct sock *sk = sock->sk;
881
882	union {
883		int val;
884		struct linger ling;
885		struct timeval tm;
886	} v;
887
888	int lv = sizeof(int);
889	int len;
890
891	if (get_user(len, optlen))
892		return -EFAULT;
893	if (len < 0)
894		return -EINVAL;
895
896	memset(&v, 0, sizeof(v));
897
898	switch (optname) {
899	case SO_DEBUG:
900		v.val = sock_flag(sk, SOCK_DBG);
901		break;
902
903	case SO_DONTROUTE:
904		v.val = sock_flag(sk, SOCK_LOCALROUTE);
905		break;
906
907	case SO_BROADCAST:
908		v.val = sock_flag(sk, SOCK_BROADCAST);
909		break;
910
911	case SO_SNDBUF:
912		v.val = sk->sk_sndbuf;
913		break;
914
915	case SO_RCVBUF:
916		v.val = sk->sk_rcvbuf;
917		break;
918
919	case SO_REUSEADDR:
920		v.val = sk->sk_reuse;
921		break;
922
923	case SO_KEEPALIVE:
924		v.val = sock_flag(sk, SOCK_KEEPOPEN);
925		break;
926
927	case SO_TYPE:
928		v.val = sk->sk_type;
929		break;
930
931	case SO_PROTOCOL:
932		v.val = sk->sk_protocol;
933		break;
934
935	case SO_DOMAIN:
936		v.val = sk->sk_family;
937		break;
938
939	case SO_ERROR:
940		v.val = -sock_error(sk);
941		if (v.val == 0)
942			v.val = xchg(&sk->sk_err_soft, 0);
943		break;
944
945	case SO_OOBINLINE:
946		v.val = sock_flag(sk, SOCK_URGINLINE);
947		break;
948
949	case SO_NO_CHECK:
950		v.val = sk->sk_no_check;
951		break;
952
953	case SO_PRIORITY:
954		v.val = sk->sk_priority;
955		break;
956
957	case SO_LINGER:
958		lv		= sizeof(v.ling);
959		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
960		v.ling.l_linger	= sk->sk_lingertime / HZ;
961		break;
962
963	case SO_BSDCOMPAT:
964		sock_warn_obsolete_bsdism("getsockopt");
965		break;
966
967	case SO_TIMESTAMP:
968		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
969				!sock_flag(sk, SOCK_RCVTSTAMPNS);
970		break;
971
972	case SO_TIMESTAMPNS:
973		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
974		break;
975
976	case SO_TIMESTAMPING:
977		v.val = 0;
978		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
979			v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
980		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
981			v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
982		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
983			v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
984		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
985			v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
986		if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
987			v.val |= SOF_TIMESTAMPING_SOFTWARE;
988		if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
989			v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
990		if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
991			v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
992		break;
993
994	case SO_RCVTIMEO:
995		lv = sizeof(struct timeval);
996		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
997			v.tm.tv_sec = 0;
998			v.tm.tv_usec = 0;
999		} else {
1000			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1001			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
1002		}
1003		break;
1004
1005	case SO_SNDTIMEO:
1006		lv = sizeof(struct timeval);
1007		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1008			v.tm.tv_sec = 0;
1009			v.tm.tv_usec = 0;
1010		} else {
1011			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1012			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1013		}
1014		break;
1015
1016	case SO_RCVLOWAT:
1017		v.val = sk->sk_rcvlowat;
1018		break;
1019
1020	case SO_SNDLOWAT:
1021		v.val = 1;
1022		break;
1023
1024	case SO_PASSCRED:
1025		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1026		break;
1027
1028	case SO_PEERCRED:
1029	{
1030		struct ucred peercred;
1031		if (len > sizeof(peercred))
1032			len = sizeof(peercred);
1033		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1034		if (copy_to_user(optval, &peercred, len))
1035			return -EFAULT;
1036		goto lenout;
1037	}
1038
1039	case SO_PEERNAME:
1040	{
1041		char address[128];
1042
1043		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1044			return -ENOTCONN;
1045		if (lv < len)
1046			return -EINVAL;
1047		if (copy_to_user(optval, address, len))
1048			return -EFAULT;
1049		goto lenout;
1050	}
1051
1052	/* Dubious BSD thing... Probably nobody even uses it, but
1053	 * the UNIX standard wants it for whatever reason... -DaveM
1054	 */
1055	case SO_ACCEPTCONN:
1056		v.val = sk->sk_state == TCP_LISTEN;
1057		break;
1058
1059	case SO_PASSSEC:
1060		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1061		break;
1062
1063	case SO_PEERSEC:
1064		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1065
1066	case SO_MARK:
1067		v.val = sk->sk_mark;
1068		break;
1069
1070	case SO_RXQ_OVFL:
1071		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1072		break;
1073
1074	case SO_WIFI_STATUS:
1075		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1076		break;
1077
1078	case SO_PEEK_OFF:
1079		if (!sock->ops->set_peek_off)
1080			return -EOPNOTSUPP;
1081
1082		v.val = sk->sk_peek_off;
1083		break;
1084	case SO_NOFCS:
1085		v.val = sock_flag(sk, SOCK_NOFCS);
1086		break;
1087	default:
1088		return -ENOPROTOOPT;
1089	}
1090
1091	if (len > lv)
1092		len = lv;
1093	if (copy_to_user(optval, &v, len))
1094		return -EFAULT;
1095lenout:
1096	if (put_user(len, optlen))
1097		return -EFAULT;
1098	return 0;
1099}
1100
1101/*
1102 * Initialize an sk_lock.
1103 *
1104 * (We also register the sk_lock with the lock validator.)
1105 */
1106static inline void sock_lock_init(struct sock *sk)
1107{
1108	sock_lock_init_class_and_name(sk,
1109			af_family_slock_key_strings[sk->sk_family],
1110			af_family_slock_keys + sk->sk_family,
1111			af_family_key_strings[sk->sk_family],
1112			af_family_keys + sk->sk_family);
1113}
1114
1115/*
1116 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1117 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1118 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1119 */
1120static void sock_copy(struct sock *nsk, const struct sock *osk)
1121{
1122#ifdef CONFIG_SECURITY_NETWORK
1123	void *sptr = nsk->sk_security;
1124#endif
1125	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1126
1127	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1128	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1129
1130#ifdef CONFIG_SECURITY_NETWORK
1131	nsk->sk_security = sptr;
1132	security_sk_clone(osk, nsk);
1133#endif
1134}
1135
1136/*
1137 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
1138 * un-modified. Special care is taken when initializing object to zero.
1139 */
1140static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1141{
1142	if (offsetof(struct sock, sk_node.next) != 0)
1143		memset(sk, 0, offsetof(struct sock, sk_node.next));
1144	memset(&sk->sk_node.pprev, 0,
1145	       size - offsetof(struct sock, sk_node.pprev));
1146}
1147
1148void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1149{
1150	unsigned long nulls1, nulls2;
1151
1152	nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1153	nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1154	if (nulls1 > nulls2)
1155		swap(nulls1, nulls2);
1156
1157	if (nulls1 != 0)
1158		memset((char *)sk, 0, nulls1);
1159	memset((char *)sk + nulls1 + sizeof(void *), 0,
1160	       nulls2 - nulls1 - sizeof(void *));
1161	memset((char *)sk + nulls2 + sizeof(void *), 0,
1162	       size - nulls2 - sizeof(void *));
1163}
1164EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1165
1166static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1167		int family)
1168{
1169	struct sock *sk;
1170	struct kmem_cache *slab;
1171
1172	slab = prot->slab;
1173	if (slab != NULL) {
1174		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1175		if (!sk)
1176			return sk;
1177		if (priority & __GFP_ZERO) {
1178			if (prot->clear_sk)
1179				prot->clear_sk(sk, prot->obj_size);
1180			else
1181				sk_prot_clear_nulls(sk, prot->obj_size);
1182		}
1183	} else
1184		sk = kmalloc(prot->obj_size, priority);
1185
1186	if (sk != NULL) {
1187		kmemcheck_annotate_bitfield(sk, flags);
1188
1189		if (security_sk_alloc(sk, family, priority))
1190			goto out_free;
1191
1192		if (!try_module_get(prot->owner))
1193			goto out_free_sec;
1194		sk_tx_queue_clear(sk);
1195	}
1196
1197	return sk;
1198
1199out_free_sec:
1200	security_sk_free(sk);
1201out_free:
1202	if (slab != NULL)
1203		kmem_cache_free(slab, sk);
1204	else
1205		kfree(sk);
1206	return NULL;
1207}
1208
1209static void sk_prot_free(struct proto *prot, struct sock *sk)
1210{
1211	struct kmem_cache *slab;
1212	struct module *owner;
1213
1214	owner = prot->owner;
1215	slab = prot->slab;
1216
1217	security_sk_free(sk);
1218	if (slab != NULL)
1219		kmem_cache_free(slab, sk);
1220	else
1221		kfree(sk);
1222	module_put(owner);
1223}
1224
1225#ifdef CONFIG_CGROUPS
1226void sock_update_classid(struct sock *sk)
1227{
1228	u32 classid;
1229
1230	rcu_read_lock();  /* doing current task, which cannot vanish. */
1231	classid = task_cls_classid(current);
1232	rcu_read_unlock();
1233	if (classid && classid != sk->sk_classid)
1234		sk->sk_classid = classid;
1235}
1236EXPORT_SYMBOL(sock_update_classid);
1237
1238void sock_update_netprioidx(struct sock *sk, struct task_struct *task)
1239{
1240	if (in_interrupt())
1241		return;
1242
1243	sk->sk_cgrp_prioidx = task_netprioidx(task);
1244}
1245EXPORT_SYMBOL_GPL(sock_update_netprioidx);
1246#endif
1247
1248/**
1249 *	sk_alloc - All socket objects are allocated here
1250 *	@net: the applicable net namespace
1251 *	@family: protocol family
1252 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1253 *	@prot: struct proto associated with this new sock instance
1254 */
1255struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1256		      struct proto *prot)
1257{
1258	struct sock *sk;
1259
1260	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1261	if (sk) {
1262		sk->sk_family = family;
1263		/*
1264		 * See comment in struct sock definition to understand
1265		 * why we need sk_prot_creator -acme
1266		 */
1267		sk->sk_prot = sk->sk_prot_creator = prot;
1268		sock_lock_init(sk);
1269		sock_net_set(sk, get_net(net));
1270		atomic_set(&sk->sk_wmem_alloc, 1);
1271
1272		sock_update_classid(sk);
1273		sock_update_netprioidx(sk, current);
1274	}
1275
1276	return sk;
1277}
1278EXPORT_SYMBOL(sk_alloc);
1279
1280static void __sk_free(struct sock *sk)
1281{
1282	struct sk_filter *filter;
1283
1284	if (sk->sk_destruct)
1285		sk->sk_destruct(sk);
1286
1287	filter = rcu_dereference_check(sk->sk_filter,
1288				       atomic_read(&sk->sk_wmem_alloc) == 0);
1289	if (filter) {
1290		sk_filter_uncharge(sk, filter);
1291		RCU_INIT_POINTER(sk->sk_filter, NULL);
1292	}
1293
1294	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1295
1296	if (atomic_read(&sk->sk_omem_alloc))
1297		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1298			 __func__, atomic_read(&sk->sk_omem_alloc));
1299
1300	if (sk->sk_peer_cred)
1301		put_cred(sk->sk_peer_cred);
1302	put_pid(sk->sk_peer_pid);
1303	put_net(sock_net(sk));
1304	sk_prot_free(sk->sk_prot_creator, sk);
1305}
1306
1307void sk_free(struct sock *sk)
1308{
1309	/*
1310	 * We subtract one from sk_wmem_alloc and can know if
1311	 * some packets are still in some tx queue.
1312	 * If not null, sock_wfree() will call __sk_free(sk) later
1313	 */
1314	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1315		__sk_free(sk);
1316}
1317EXPORT_SYMBOL(sk_free);
1318
1319/*
1320 * Last sock_put should drop reference to sk->sk_net. It has already
1321 * been dropped in sk_change_net. Taking reference to stopping namespace
1322 * is not an option.
1323 * Take reference to a socket to remove it from hash _alive_ and after that
1324 * destroy it in the context of init_net.
1325 */
1326void sk_release_kernel(struct sock *sk)
1327{
1328	if (sk == NULL || sk->sk_socket == NULL)
1329		return;
1330
1331	sock_hold(sk);
1332	sock_release(sk->sk_socket);
1333	release_net(sock_net(sk));
1334	sock_net_set(sk, get_net(&init_net));
1335	sock_put(sk);
1336}
1337EXPORT_SYMBOL(sk_release_kernel);
1338
1339static void sk_update_clone(const struct sock *sk, struct sock *newsk)
1340{
1341	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1342		sock_update_memcg(newsk);
1343}
1344
1345/**
1346 *	sk_clone_lock - clone a socket, and lock its clone
1347 *	@sk: the socket to clone
1348 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1349 *
1350 *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1351 */
1352struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1353{
1354	struct sock *newsk;
1355
1356	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1357	if (newsk != NULL) {
1358		struct sk_filter *filter;
1359
1360		sock_copy(newsk, sk);
1361
1362		/* SANITY */
1363		get_net(sock_net(newsk));
1364		sk_node_init(&newsk->sk_node);
1365		sock_lock_init(newsk);
1366		bh_lock_sock(newsk);
1367		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1368		newsk->sk_backlog.len = 0;
1369
1370		atomic_set(&newsk->sk_rmem_alloc, 0);
1371		/*
1372		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1373		 */
1374		atomic_set(&newsk->sk_wmem_alloc, 1);
1375		atomic_set(&newsk->sk_omem_alloc, 0);
1376		skb_queue_head_init(&newsk->sk_receive_queue);
1377		skb_queue_head_init(&newsk->sk_write_queue);
1378#ifdef CONFIG_NET_DMA
1379		skb_queue_head_init(&newsk->sk_async_wait_queue);
1380#endif
1381
1382		spin_lock_init(&newsk->sk_dst_lock);
1383		rwlock_init(&newsk->sk_callback_lock);
1384		lockdep_set_class_and_name(&newsk->sk_callback_lock,
1385				af_callback_keys + newsk->sk_family,
1386				af_family_clock_key_strings[newsk->sk_family]);
1387
1388		newsk->sk_dst_cache	= NULL;
1389		newsk->sk_wmem_queued	= 0;
1390		newsk->sk_forward_alloc = 0;
1391		newsk->sk_send_head	= NULL;
1392		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1393
1394		sock_reset_flag(newsk, SOCK_DONE);
1395		skb_queue_head_init(&newsk->sk_error_queue);
1396
1397		filter = rcu_dereference_protected(newsk->sk_filter, 1);
1398		if (filter != NULL)
1399			sk_filter_charge(newsk, filter);
1400
1401		if (unlikely(xfrm_sk_clone_policy(newsk))) {
1402			/* It is still raw copy of parent, so invalidate
1403			 * destructor and make plain sk_free() */
1404			newsk->sk_destruct = NULL;
1405			bh_unlock_sock(newsk);
1406			sk_free(newsk);
1407			newsk = NULL;
1408			goto out;
1409		}
1410
1411		newsk->sk_err	   = 0;
1412		newsk->sk_priority = 0;
1413		/*
1414		 * Before updating sk_refcnt, we must commit prior changes to memory
1415		 * (Documentation/RCU/rculist_nulls.txt for details)
1416		 */
1417		smp_wmb();
1418		atomic_set(&newsk->sk_refcnt, 2);
1419
1420		/*
1421		 * Increment the counter in the same struct proto as the master
1422		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1423		 * is the same as sk->sk_prot->socks, as this field was copied
1424		 * with memcpy).
1425		 *
1426		 * This _changes_ the previous behaviour, where
1427		 * tcp_create_openreq_child always was incrementing the
1428		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1429		 * to be taken into account in all callers. -acme
1430		 */
1431		sk_refcnt_debug_inc(newsk);
1432		sk_set_socket(newsk, NULL);
1433		newsk->sk_wq = NULL;
1434
1435		sk_update_clone(sk, newsk);
1436
1437		if (newsk->sk_prot->sockets_allocated)
1438			sk_sockets_allocated_inc(newsk);
1439
1440		if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1441			net_enable_timestamp();
1442	}
1443out:
1444	return newsk;
1445}
1446EXPORT_SYMBOL_GPL(sk_clone_lock);
1447
1448void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1449{
1450	__sk_dst_set(sk, dst);
1451	sk->sk_route_caps = dst->dev->features;
1452	if (sk->sk_route_caps & NETIF_F_GSO)
1453		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1454	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1455	if (sk_can_gso(sk)) {
1456		if (dst->header_len) {
1457			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1458		} else {
1459			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1460			sk->sk_gso_max_size = dst->dev->gso_max_size;
1461			sk->sk_gso_max_segs = dst->dev->gso_max_segs;
1462		}
1463	}
1464}
1465EXPORT_SYMBOL_GPL(sk_setup_caps);
1466
1467void __init sk_init(void)
1468{
1469	if (totalram_pages <= 4096) {
1470		sysctl_wmem_max = 32767;
1471		sysctl_rmem_max = 32767;
1472		sysctl_wmem_default = 32767;
1473		sysctl_rmem_default = 32767;
1474	} else if (totalram_pages >= 131072) {
1475		sysctl_wmem_max = 131071;
1476		sysctl_rmem_max = 131071;
1477	}
1478}
1479
1480/*
1481 *	Simple resource managers for sockets.
1482 */
1483
1484
1485/*
1486 * Write buffer destructor automatically called from kfree_skb.
1487 */
1488void sock_wfree(struct sk_buff *skb)
1489{
1490	struct sock *sk = skb->sk;
1491	unsigned int len = skb->truesize;
1492
1493	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1494		/*
1495		 * Keep a reference on sk_wmem_alloc, this will be released
1496		 * after sk_write_space() call
1497		 */
1498		atomic_sub(len - 1, &sk->sk_wmem_alloc);
1499		sk->sk_write_space(sk);
1500		len = 1;
1501	}
1502	/*
1503	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1504	 * could not do because of in-flight packets
1505	 */
1506	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1507		__sk_free(sk);
1508}
1509EXPORT_SYMBOL(sock_wfree);
1510
1511/*
1512 * Read buffer destructor automatically called from kfree_skb.
1513 */
1514void sock_rfree(struct sk_buff *skb)
1515{
1516	struct sock *sk = skb->sk;
1517	unsigned int len = skb->truesize;
1518
1519	atomic_sub(len, &sk->sk_rmem_alloc);
1520	sk_mem_uncharge(sk, len);
1521}
1522EXPORT_SYMBOL(sock_rfree);
1523
1524void sock_edemux(struct sk_buff *skb)
1525{
1526	sock_put(skb->sk);
1527}
1528EXPORT_SYMBOL(sock_edemux);
1529
1530int sock_i_uid(struct sock *sk)
1531{
1532	int uid;
1533
1534	read_lock_bh(&sk->sk_callback_lock);
1535	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1536	read_unlock_bh(&sk->sk_callback_lock);
1537	return uid;
1538}
1539EXPORT_SYMBOL(sock_i_uid);
1540
1541unsigned long sock_i_ino(struct sock *sk)
1542{
1543	unsigned long ino;
1544
1545	read_lock_bh(&sk->sk_callback_lock);
1546	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1547	read_unlock_bh(&sk->sk_callback_lock);
1548	return ino;
1549}
1550EXPORT_SYMBOL(sock_i_ino);
1551
1552/*
1553 * Allocate a skb from the socket's send buffer.
1554 */
1555struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1556			     gfp_t priority)
1557{
1558	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1559		struct sk_buff *skb = alloc_skb(size, priority);
1560		if (skb) {
1561			skb_set_owner_w(skb, sk);
1562			return skb;
1563		}
1564	}
1565	return NULL;
1566}
1567EXPORT_SYMBOL(sock_wmalloc);
1568
1569/*
1570 * Allocate a skb from the socket's receive buffer.
1571 */
1572struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1573			     gfp_t priority)
1574{
1575	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1576		struct sk_buff *skb = alloc_skb(size, priority);
1577		if (skb) {
1578			skb_set_owner_r(skb, sk);
1579			return skb;
1580		}
1581	}
1582	return NULL;
1583}
1584
1585/*
1586 * Allocate a memory block from the socket's option memory buffer.
1587 */
1588void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1589{
1590	if ((unsigned int)size <= sysctl_optmem_max &&
1591	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1592		void *mem;
1593		/* First do the add, to avoid the race if kmalloc
1594		 * might sleep.
1595		 */
1596		atomic_add(size, &sk->sk_omem_alloc);
1597		mem = kmalloc(size, priority);
1598		if (mem)
1599			return mem;
1600		atomic_sub(size, &sk->sk_omem_alloc);
1601	}
1602	return NULL;
1603}
1604EXPORT_SYMBOL(sock_kmalloc);
1605
1606/*
1607 * Free an option memory block.
1608 */
1609void sock_kfree_s(struct sock *sk, void *mem, int size)
1610{
1611	kfree(mem);
1612	atomic_sub(size, &sk->sk_omem_alloc);
1613}
1614EXPORT_SYMBOL(sock_kfree_s);
1615
1616/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1617   I think, these locks should be removed for datagram sockets.
1618 */
1619static long sock_wait_for_wmem(struct sock *sk, long timeo)
1620{
1621	DEFINE_WAIT(wait);
1622
1623	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1624	for (;;) {
1625		if (!timeo)
1626			break;
1627		if (signal_pending(current))
1628			break;
1629		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1630		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1631		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1632			break;
1633		if (sk->sk_shutdown & SEND_SHUTDOWN)
1634			break;
1635		if (sk->sk_err)
1636			break;
1637		timeo = schedule_timeout(timeo);
1638	}
1639	finish_wait(sk_sleep(sk), &wait);
1640	return timeo;
1641}
1642
1643
1644/*
1645 *	Generic send/receive buffer handlers
1646 */
1647
1648struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1649				     unsigned long data_len, int noblock,
1650				     int *errcode)
1651{
1652	struct sk_buff *skb;
1653	gfp_t gfp_mask;
1654	long timeo;
1655	int err;
1656	int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1657
1658	err = -EMSGSIZE;
1659	if (npages > MAX_SKB_FRAGS)
1660		goto failure;
1661
1662	gfp_mask = sk->sk_allocation;
1663	if (gfp_mask & __GFP_WAIT)
1664		gfp_mask |= __GFP_REPEAT;
1665
1666	timeo = sock_sndtimeo(sk, noblock);
1667	while (1) {
1668		err = sock_error(sk);
1669		if (err != 0)
1670			goto failure;
1671
1672		err = -EPIPE;
1673		if (sk->sk_shutdown & SEND_SHUTDOWN)
1674			goto failure;
1675
1676		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1677			skb = alloc_skb(header_len, gfp_mask);
1678			if (skb) {
1679				int i;
1680
1681				/* No pages, we're done... */
1682				if (!data_len)
1683					break;
1684
1685				skb->truesize += data_len;
1686				skb_shinfo(skb)->nr_frags = npages;
1687				for (i = 0; i < npages; i++) {
1688					struct page *page;
1689
1690					page = alloc_pages(sk->sk_allocation, 0);
1691					if (!page) {
1692						err = -ENOBUFS;
1693						skb_shinfo(skb)->nr_frags = i;
1694						kfree_skb(skb);
1695						goto failure;
1696					}
1697
1698					__skb_fill_page_desc(skb, i,
1699							page, 0,
1700							(data_len >= PAGE_SIZE ?
1701							 PAGE_SIZE :
1702							 data_len));
1703					data_len -= PAGE_SIZE;
1704				}
1705
1706				/* Full success... */
1707				break;
1708			}
1709			err = -ENOBUFS;
1710			goto failure;
1711		}
1712		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1713		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1714		err = -EAGAIN;
1715		if (!timeo)
1716			goto failure;
1717		if (signal_pending(current))
1718			goto interrupted;
1719		timeo = sock_wait_for_wmem(sk, timeo);
1720	}
1721
1722	skb_set_owner_w(skb, sk);
1723	return skb;
1724
1725interrupted:
1726	err = sock_intr_errno(timeo);
1727failure:
1728	*errcode = err;
1729	return NULL;
1730}
1731EXPORT_SYMBOL(sock_alloc_send_pskb);
1732
1733struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1734				    int noblock, int *errcode)
1735{
1736	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1737}
1738EXPORT_SYMBOL(sock_alloc_send_skb);
1739
1740static void __lock_sock(struct sock *sk)
1741	__releases(&sk->sk_lock.slock)
1742	__acquires(&sk->sk_lock.slock)
1743{
1744	DEFINE_WAIT(wait);
1745
1746	for (;;) {
1747		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1748					TASK_UNINTERRUPTIBLE);
1749		spin_unlock_bh(&sk->sk_lock.slock);
1750		schedule();
1751		spin_lock_bh(&sk->sk_lock.slock);
1752		if (!sock_owned_by_user(sk))
1753			break;
1754	}
1755	finish_wait(&sk->sk_lock.wq, &wait);
1756}
1757
1758static void __release_sock(struct sock *sk)
1759	__releases(&sk->sk_lock.slock)
1760	__acquires(&sk->sk_lock.slock)
1761{
1762	struct sk_buff *skb = sk->sk_backlog.head;
1763
1764	do {
1765		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1766		bh_unlock_sock(sk);
1767
1768		do {
1769			struct sk_buff *next = skb->next;
1770
1771			prefetch(next);
1772			WARN_ON_ONCE(skb_dst_is_noref(skb));
1773			skb->next = NULL;
1774			sk_backlog_rcv(sk, skb);
1775
1776			/*
1777			 * We are in process context here with softirqs
1778			 * disabled, use cond_resched_softirq() to preempt.
1779			 * This is safe to do because we've taken the backlog
1780			 * queue private:
1781			 */
1782			cond_resched_softirq();
1783
1784			skb = next;
1785		} while (skb != NULL);
1786
1787		bh_lock_sock(sk);
1788	} while ((skb = sk->sk_backlog.head) != NULL);
1789
1790	/*
1791	 * Doing the zeroing here guarantee we can not loop forever
1792	 * while a wild producer attempts to flood us.
1793	 */
1794	sk->sk_backlog.len = 0;
1795}
1796
1797/**
1798 * sk_wait_data - wait for data to arrive at sk_receive_queue
1799 * @sk:    sock to wait on
1800 * @timeo: for how long
1801 *
1802 * Now socket state including sk->sk_err is changed only under lock,
1803 * hence we may omit checks after joining wait queue.
1804 * We check receive queue before schedule() only as optimization;
1805 * it is very likely that release_sock() added new data.
1806 */
1807int sk_wait_data(struct sock *sk, long *timeo)
1808{
1809	int rc;
1810	DEFINE_WAIT(wait);
1811
1812	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1813	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1814	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1815	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1816	finish_wait(sk_sleep(sk), &wait);
1817	return rc;
1818}
1819EXPORT_SYMBOL(sk_wait_data);
1820
1821/**
1822 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1823 *	@sk: socket
1824 *	@size: memory size to allocate
1825 *	@kind: allocation type
1826 *
1827 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1828 *	rmem allocation. This function assumes that protocols which have
1829 *	memory_pressure use sk_wmem_queued as write buffer accounting.
1830 */
1831int __sk_mem_schedule(struct sock *sk, int size, int kind)
1832{
1833	struct proto *prot = sk->sk_prot;
1834	int amt = sk_mem_pages(size);
1835	long allocated;
1836	int parent_status = UNDER_LIMIT;
1837
1838	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1839
1840	allocated = sk_memory_allocated_add(sk, amt, &parent_status);
1841
1842	/* Under limit. */
1843	if (parent_status == UNDER_LIMIT &&
1844			allocated <= sk_prot_mem_limits(sk, 0)) {
1845		sk_leave_memory_pressure(sk);
1846		return 1;
1847	}
1848
1849	/* Under pressure. (we or our parents) */
1850	if ((parent_status > SOFT_LIMIT) ||
1851			allocated > sk_prot_mem_limits(sk, 1))
1852		sk_enter_memory_pressure(sk);
1853
1854	/* Over hard limit (we or our parents) */
1855	if ((parent_status == OVER_LIMIT) ||
1856			(allocated > sk_prot_mem_limits(sk, 2)))
1857		goto suppress_allocation;
1858
1859	/* guarantee minimum buffer size under pressure */
1860	if (kind == SK_MEM_RECV) {
1861		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1862			return 1;
1863
1864	} else { /* SK_MEM_SEND */
1865		if (sk->sk_type == SOCK_STREAM) {
1866			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1867				return 1;
1868		} else if (atomic_read(&sk->sk_wmem_alloc) <
1869			   prot->sysctl_wmem[0])
1870				return 1;
1871	}
1872
1873	if (sk_has_memory_pressure(sk)) {
1874		int alloc;
1875
1876		if (!sk_under_memory_pressure(sk))
1877			return 1;
1878		alloc = sk_sockets_allocated_read_positive(sk);
1879		if (sk_prot_mem_limits(sk, 2) > alloc *
1880		    sk_mem_pages(sk->sk_wmem_queued +
1881				 atomic_read(&sk->sk_rmem_alloc) +
1882				 sk->sk_forward_alloc))
1883			return 1;
1884	}
1885
1886suppress_allocation:
1887
1888	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1889		sk_stream_moderate_sndbuf(sk);
1890
1891		/* Fail only if socket is _under_ its sndbuf.
1892		 * In this case we cannot block, so that we have to fail.
1893		 */
1894		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1895			return 1;
1896	}
1897
1898	trace_sock_exceed_buf_limit(sk, prot, allocated);
1899
1900	/* Alas. Undo changes. */
1901	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1902
1903	sk_memory_allocated_sub(sk, amt);
1904
1905	return 0;
1906}
1907EXPORT_SYMBOL(__sk_mem_schedule);
1908
1909/**
1910 *	__sk_reclaim - reclaim memory_allocated
1911 *	@sk: socket
1912 */
1913void __sk_mem_reclaim(struct sock *sk)
1914{
1915	sk_memory_allocated_sub(sk,
1916				sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT);
1917	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1918
1919	if (sk_under_memory_pressure(sk) &&
1920	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
1921		sk_leave_memory_pressure(sk);
1922}
1923EXPORT_SYMBOL(__sk_mem_reclaim);
1924
1925
1926/*
1927 * Set of default routines for initialising struct proto_ops when
1928 * the protocol does not support a particular function. In certain
1929 * cases where it makes no sense for a protocol to have a "do nothing"
1930 * function, some default processing is provided.
1931 */
1932
1933int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1934{
1935	return -EOPNOTSUPP;
1936}
1937EXPORT_SYMBOL(sock_no_bind);
1938
1939int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1940		    int len, int flags)
1941{
1942	return -EOPNOTSUPP;
1943}
1944EXPORT_SYMBOL(sock_no_connect);
1945
1946int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1947{
1948	return -EOPNOTSUPP;
1949}
1950EXPORT_SYMBOL(sock_no_socketpair);
1951
1952int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1953{
1954	return -EOPNOTSUPP;
1955}
1956EXPORT_SYMBOL(sock_no_accept);
1957
1958int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1959		    int *len, int peer)
1960{
1961	return -EOPNOTSUPP;
1962}
1963EXPORT_SYMBOL(sock_no_getname);
1964
1965unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1966{
1967	return 0;
1968}
1969EXPORT_SYMBOL(sock_no_poll);
1970
1971int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1972{
1973	return -EOPNOTSUPP;
1974}
1975EXPORT_SYMBOL(sock_no_ioctl);
1976
1977int sock_no_listen(struct socket *sock, int backlog)
1978{
1979	return -EOPNOTSUPP;
1980}
1981EXPORT_SYMBOL(sock_no_listen);
1982
1983int sock_no_shutdown(struct socket *sock, int how)
1984{
1985	return -EOPNOTSUPP;
1986}
1987EXPORT_SYMBOL(sock_no_shutdown);
1988
1989int sock_no_setsockopt(struct socket *sock, int level, int optname,
1990		    char __user *optval, unsigned int optlen)
1991{
1992	return -EOPNOTSUPP;
1993}
1994EXPORT_SYMBOL(sock_no_setsockopt);
1995
1996int sock_no_getsockopt(struct socket *sock, int level, int optname,
1997		    char __user *optval, int __user *optlen)
1998{
1999	return -EOPNOTSUPP;
2000}
2001EXPORT_SYMBOL(sock_no_getsockopt);
2002
2003int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2004		    size_t len)
2005{
2006	return -EOPNOTSUPP;
2007}
2008EXPORT_SYMBOL(sock_no_sendmsg);
2009
2010int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2011		    size_t len, int flags)
2012{
2013	return -EOPNOTSUPP;
2014}
2015EXPORT_SYMBOL(sock_no_recvmsg);
2016
2017int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2018{
2019	/* Mirror missing mmap method error code */
2020	return -ENODEV;
2021}
2022EXPORT_SYMBOL(sock_no_mmap);
2023
2024ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2025{
2026	ssize_t res;
2027	struct msghdr msg = {.msg_flags = flags};
2028	struct kvec iov;
2029	char *kaddr = kmap(page);
2030	iov.iov_base = kaddr + offset;
2031	iov.iov_len = size;
2032	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2033	kunmap(page);
2034	return res;
2035}
2036EXPORT_SYMBOL(sock_no_sendpage);
2037
2038/*
2039 *	Default Socket Callbacks
2040 */
2041
2042static void sock_def_wakeup(struct sock *sk)
2043{
2044	struct socket_wq *wq;
2045
2046	rcu_read_lock();
2047	wq = rcu_dereference(sk->sk_wq);
2048	if (wq_has_sleeper(wq))
2049		wake_up_interruptible_all(&wq->wait);
2050	rcu_read_unlock();
2051}
2052
2053static void sock_def_error_report(struct sock *sk)
2054{
2055	struct socket_wq *wq;
2056
2057	rcu_read_lock();
2058	wq = rcu_dereference(sk->sk_wq);
2059	if (wq_has_sleeper(wq))
2060		wake_up_interruptible_poll(&wq->wait, POLLERR);
2061	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2062	rcu_read_unlock();
2063}
2064
2065static void sock_def_readable(struct sock *sk, int len)
2066{
2067	struct socket_wq *wq;
2068
2069	rcu_read_lock();
2070	wq = rcu_dereference(sk->sk_wq);
2071	if (wq_has_sleeper(wq))
2072		wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2073						POLLRDNORM | POLLRDBAND);
2074	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2075	rcu_read_unlock();
2076}
2077
2078static void sock_def_write_space(struct sock *sk)
2079{
2080	struct socket_wq *wq;
2081
2082	rcu_read_lock();
2083
2084	/* Do not wake up a writer until he can make "significant"
2085	 * progress.  --DaveM
2086	 */
2087	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2088		wq = rcu_dereference(sk->sk_wq);
2089		if (wq_has_sleeper(wq))
2090			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2091						POLLWRNORM | POLLWRBAND);
2092
2093		/* Should agree with poll, otherwise some programs break */
2094		if (sock_writeable(sk))
2095			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2096	}
2097
2098	rcu_read_unlock();
2099}
2100
2101static void sock_def_destruct(struct sock *sk)
2102{
2103	kfree(sk->sk_protinfo);
2104}
2105
2106void sk_send_sigurg(struct sock *sk)
2107{
2108	if (sk->sk_socket && sk->sk_socket->file)
2109		if (send_sigurg(&sk->sk_socket->file->f_owner))
2110			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2111}
2112EXPORT_SYMBOL(sk_send_sigurg);
2113
2114void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2115		    unsigned long expires)
2116{
2117	if (!mod_timer(timer, expires))
2118		sock_hold(sk);
2119}
2120EXPORT_SYMBOL(sk_reset_timer);
2121
2122void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2123{
2124	if (timer_pending(timer) && del_timer(timer))
2125		__sock_put(sk);
2126}
2127EXPORT_SYMBOL(sk_stop_timer);
2128
2129void sock_init_data(struct socket *sock, struct sock *sk)
2130{
2131	skb_queue_head_init(&sk->sk_receive_queue);
2132	skb_queue_head_init(&sk->sk_write_queue);
2133	skb_queue_head_init(&sk->sk_error_queue);
2134#ifdef CONFIG_NET_DMA
2135	skb_queue_head_init(&sk->sk_async_wait_queue);
2136#endif
2137
2138	sk->sk_send_head	=	NULL;
2139
2140	init_timer(&sk->sk_timer);
2141
2142	sk->sk_allocation	=	GFP_KERNEL;
2143	sk->sk_rcvbuf		=	sysctl_rmem_default;
2144	sk->sk_sndbuf		=	sysctl_wmem_default;
2145	sk->sk_state		=	TCP_CLOSE;
2146	sk_set_socket(sk, sock);
2147
2148	sock_set_flag(sk, SOCK_ZAPPED);
2149
2150	if (sock) {
2151		sk->sk_type	=	sock->type;
2152		sk->sk_wq	=	sock->wq;
2153		sock->sk	=	sk;
2154	} else
2155		sk->sk_wq	=	NULL;
2156
2157	spin_lock_init(&sk->sk_dst_lock);
2158	rwlock_init(&sk->sk_callback_lock);
2159	lockdep_set_class_and_name(&sk->sk_callback_lock,
2160			af_callback_keys + sk->sk_family,
2161			af_family_clock_key_strings[sk->sk_family]);
2162
2163	sk->sk_state_change	=	sock_def_wakeup;
2164	sk->sk_data_ready	=	sock_def_readable;
2165	sk->sk_write_space	=	sock_def_write_space;
2166	sk->sk_error_report	=	sock_def_error_report;
2167	sk->sk_destruct		=	sock_def_destruct;
2168
2169	sk->sk_sndmsg_page	=	NULL;
2170	sk->sk_sndmsg_off	=	0;
2171	sk->sk_peek_off		=	-1;
2172
2173	sk->sk_peer_pid 	=	NULL;
2174	sk->sk_peer_cred	=	NULL;
2175	sk->sk_write_pending	=	0;
2176	sk->sk_rcvlowat		=	1;
2177	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2178	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2179
2180	sk->sk_stamp = ktime_set(-1L, 0);
2181
2182	/*
2183	 * Before updating sk_refcnt, we must commit prior changes to memory
2184	 * (Documentation/RCU/rculist_nulls.txt for details)
2185	 */
2186	smp_wmb();
2187	atomic_set(&sk->sk_refcnt, 1);
2188	atomic_set(&sk->sk_drops, 0);
2189}
2190EXPORT_SYMBOL(sock_init_data);
2191
2192void lock_sock_nested(struct sock *sk, int subclass)
2193{
2194	might_sleep();
2195	spin_lock_bh(&sk->sk_lock.slock);
2196	if (sk->sk_lock.owned)
2197		__lock_sock(sk);
2198	sk->sk_lock.owned = 1;
2199	spin_unlock(&sk->sk_lock.slock);
2200	/*
2201	 * The sk_lock has mutex_lock() semantics here:
2202	 */
2203	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2204	local_bh_enable();
2205}
2206EXPORT_SYMBOL(lock_sock_nested);
2207
2208void release_sock(struct sock *sk)
2209{
2210	/*
2211	 * The sk_lock has mutex_unlock() semantics:
2212	 */
2213	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2214
2215	spin_lock_bh(&sk->sk_lock.slock);
2216	if (sk->sk_backlog.tail)
2217		__release_sock(sk);
2218
2219	if (sk->sk_prot->release_cb)
2220		sk->sk_prot->release_cb(sk);
2221
2222	sk->sk_lock.owned = 0;
2223	if (waitqueue_active(&sk->sk_lock.wq))
2224		wake_up(&sk->sk_lock.wq);
2225	spin_unlock_bh(&sk->sk_lock.slock);
2226}
2227EXPORT_SYMBOL(release_sock);
2228
2229/**
2230 * lock_sock_fast - fast version of lock_sock
2231 * @sk: socket
2232 *
2233 * This version should be used for very small section, where process wont block
2234 * return false if fast path is taken
2235 *   sk_lock.slock locked, owned = 0, BH disabled
2236 * return true if slow path is taken
2237 *   sk_lock.slock unlocked, owned = 1, BH enabled
2238 */
2239bool lock_sock_fast(struct sock *sk)
2240{
2241	might_sleep();
2242	spin_lock_bh(&sk->sk_lock.slock);
2243
2244	if (!sk->sk_lock.owned)
2245		/*
2246		 * Note : We must disable BH
2247		 */
2248		return false;
2249
2250	__lock_sock(sk);
2251	sk->sk_lock.owned = 1;
2252	spin_unlock(&sk->sk_lock.slock);
2253	/*
2254	 * The sk_lock has mutex_lock() semantics here:
2255	 */
2256	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2257	local_bh_enable();
2258	return true;
2259}
2260EXPORT_SYMBOL(lock_sock_fast);
2261
2262int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2263{
2264	struct timeval tv;
2265	if (!sock_flag(sk, SOCK_TIMESTAMP))
2266		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2267	tv = ktime_to_timeval(sk->sk_stamp);
2268	if (tv.tv_sec == -1)
2269		return -ENOENT;
2270	if (tv.tv_sec == 0) {
2271		sk->sk_stamp = ktime_get_real();
2272		tv = ktime_to_timeval(sk->sk_stamp);
2273	}
2274	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2275}
2276EXPORT_SYMBOL(sock_get_timestamp);
2277
2278int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2279{
2280	struct timespec ts;
2281	if (!sock_flag(sk, SOCK_TIMESTAMP))
2282		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2283	ts = ktime_to_timespec(sk->sk_stamp);
2284	if (ts.tv_sec == -1)
2285		return -ENOENT;
2286	if (ts.tv_sec == 0) {
2287		sk->sk_stamp = ktime_get_real();
2288		ts = ktime_to_timespec(sk->sk_stamp);
2289	}
2290	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2291}
2292EXPORT_SYMBOL(sock_get_timestampns);
2293
2294void sock_enable_timestamp(struct sock *sk, int flag)
2295{
2296	if (!sock_flag(sk, flag)) {
2297		unsigned long previous_flags = sk->sk_flags;
2298
2299		sock_set_flag(sk, flag);
2300		/*
2301		 * we just set one of the two flags which require net
2302		 * time stamping, but time stamping might have been on
2303		 * already because of the other one
2304		 */
2305		if (!(previous_flags & SK_FLAGS_TIMESTAMP))
2306			net_enable_timestamp();
2307	}
2308}
2309
2310/*
2311 *	Get a socket option on an socket.
2312 *
2313 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2314 *	asynchronous errors should be reported by getsockopt. We assume
2315 *	this means if you specify SO_ERROR (otherwise whats the point of it).
2316 */
2317int sock_common_getsockopt(struct socket *sock, int level, int optname,
2318			   char __user *optval, int __user *optlen)
2319{
2320	struct sock *sk = sock->sk;
2321
2322	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2323}
2324EXPORT_SYMBOL(sock_common_getsockopt);
2325
2326#ifdef CONFIG_COMPAT
2327int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2328				  char __user *optval, int __user *optlen)
2329{
2330	struct sock *sk = sock->sk;
2331
2332	if (sk->sk_prot->compat_getsockopt != NULL)
2333		return sk->sk_prot->compat_getsockopt(sk, level, optname,
2334						      optval, optlen);
2335	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2336}
2337EXPORT_SYMBOL(compat_sock_common_getsockopt);
2338#endif
2339
2340int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2341			struct msghdr *msg, size_t size, int flags)
2342{
2343	struct sock *sk = sock->sk;
2344	int addr_len = 0;
2345	int err;
2346
2347	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2348				   flags & ~MSG_DONTWAIT, &addr_len);
2349	if (err >= 0)
2350		msg->msg_namelen = addr_len;
2351	return err;
2352}
2353EXPORT_SYMBOL(sock_common_recvmsg);
2354
2355/*
2356 *	Set socket options on an inet socket.
2357 */
2358int sock_common_setsockopt(struct socket *sock, int level, int optname,
2359			   char __user *optval, unsigned int optlen)
2360{
2361	struct sock *sk = sock->sk;
2362
2363	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2364}
2365EXPORT_SYMBOL(sock_common_setsockopt);
2366
2367#ifdef CONFIG_COMPAT
2368int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2369				  char __user *optval, unsigned int optlen)
2370{
2371	struct sock *sk = sock->sk;
2372
2373	if (sk->sk_prot->compat_setsockopt != NULL)
2374		return sk->sk_prot->compat_setsockopt(sk, level, optname,
2375						      optval, optlen);
2376	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2377}
2378EXPORT_SYMBOL(compat_sock_common_setsockopt);
2379#endif
2380
2381void sk_common_release(struct sock *sk)
2382{
2383	if (sk->sk_prot->destroy)
2384		sk->sk_prot->destroy(sk);
2385
2386	/*
2387	 * Observation: when sock_common_release is called, processes have
2388	 * no access to socket. But net still has.
2389	 * Step one, detach it from networking:
2390	 *
2391	 * A. Remove from hash tables.
2392	 */
2393
2394	sk->sk_prot->unhash(sk);
2395
2396	/*
2397	 * In this point socket cannot receive new packets, but it is possible
2398	 * that some packets are in flight because some CPU runs receiver and
2399	 * did hash table lookup before we unhashed socket. They will achieve
2400	 * receive queue and will be purged by socket destructor.
2401	 *
2402	 * Also we still have packets pending on receive queue and probably,
2403	 * our own packets waiting in device queues. sock_destroy will drain
2404	 * receive queue, but transmitted packets will delay socket destruction
2405	 * until the last reference will be released.
2406	 */
2407
2408	sock_orphan(sk);
2409
2410	xfrm_sk_free_policy(sk);
2411
2412	sk_refcnt_debug_release(sk);
2413	sock_put(sk);
2414}
2415EXPORT_SYMBOL(sk_common_release);
2416
2417#ifdef CONFIG_PROC_FS
2418#define PROTO_INUSE_NR	64	/* should be enough for the first time */
2419struct prot_inuse {
2420	int val[PROTO_INUSE_NR];
2421};
2422
2423static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2424
2425#ifdef CONFIG_NET_NS
2426void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2427{
2428	__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2429}
2430EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2431
2432int sock_prot_inuse_get(struct net *net, struct proto *prot)
2433{
2434	int cpu, idx = prot->inuse_idx;
2435	int res = 0;
2436
2437	for_each_possible_cpu(cpu)
2438		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2439
2440	return res >= 0 ? res : 0;
2441}
2442EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2443
2444static int __net_init sock_inuse_init_net(struct net *net)
2445{
2446	net->core.inuse = alloc_percpu(struct prot_inuse);
2447	return net->core.inuse ? 0 : -ENOMEM;
2448}
2449
2450static void __net_exit sock_inuse_exit_net(struct net *net)
2451{
2452	free_percpu(net->core.inuse);
2453}
2454
2455static struct pernet_operations net_inuse_ops = {
2456	.init = sock_inuse_init_net,
2457	.exit = sock_inuse_exit_net,
2458};
2459
2460static __init int net_inuse_init(void)
2461{
2462	if (register_pernet_subsys(&net_inuse_ops))
2463		panic("Cannot initialize net inuse counters");
2464
2465	return 0;
2466}
2467
2468core_initcall(net_inuse_init);
2469#else
2470static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2471
2472void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2473{
2474	__this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2475}
2476EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2477
2478int sock_prot_inuse_get(struct net *net, struct proto *prot)
2479{
2480	int cpu, idx = prot->inuse_idx;
2481	int res = 0;
2482
2483	for_each_possible_cpu(cpu)
2484		res += per_cpu(prot_inuse, cpu).val[idx];
2485
2486	return res >= 0 ? res : 0;
2487}
2488EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2489#endif
2490
2491static void assign_proto_idx(struct proto *prot)
2492{
2493	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2494
2495	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2496		pr_err("PROTO_INUSE_NR exhausted\n");
2497		return;
2498	}
2499
2500	set_bit(prot->inuse_idx, proto_inuse_idx);
2501}
2502
2503static void release_proto_idx(struct proto *prot)
2504{
2505	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2506		clear_bit(prot->inuse_idx, proto_inuse_idx);
2507}
2508#else
2509static inline void assign_proto_idx(struct proto *prot)
2510{
2511}
2512
2513static inline void release_proto_idx(struct proto *prot)
2514{
2515}
2516#endif
2517
2518int proto_register(struct proto *prot, int alloc_slab)
2519{
2520	if (alloc_slab) {
2521		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2522					SLAB_HWCACHE_ALIGN | prot->slab_flags,
2523					NULL);
2524
2525		if (prot->slab == NULL) {
2526			pr_crit("%s: Can't create sock SLAB cache!\n",
2527				prot->name);
2528			goto out;
2529		}
2530
2531		if (prot->rsk_prot != NULL) {
2532			prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2533			if (prot->rsk_prot->slab_name == NULL)
2534				goto out_free_sock_slab;
2535
2536			prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2537								 prot->rsk_prot->obj_size, 0,
2538								 SLAB_HWCACHE_ALIGN, NULL);
2539
2540			if (prot->rsk_prot->slab == NULL) {
2541				pr_crit("%s: Can't create request sock SLAB cache!\n",
2542					prot->name);
2543				goto out_free_request_sock_slab_name;
2544			}
2545		}
2546
2547		if (prot->twsk_prot != NULL) {
2548			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2549
2550			if (prot->twsk_prot->twsk_slab_name == NULL)
2551				goto out_free_request_sock_slab;
2552
2553			prot->twsk_prot->twsk_slab =
2554				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2555						  prot->twsk_prot->twsk_obj_size,
2556						  0,
2557						  SLAB_HWCACHE_ALIGN |
2558							prot->slab_flags,
2559						  NULL);
2560			if (prot->twsk_prot->twsk_slab == NULL)
2561				goto out_free_timewait_sock_slab_name;
2562		}
2563	}
2564
2565	mutex_lock(&proto_list_mutex);
2566	list_add(&prot->node, &proto_list);
2567	assign_proto_idx(prot);
2568	mutex_unlock(&proto_list_mutex);
2569	return 0;
2570
2571out_free_timewait_sock_slab_name:
2572	kfree(prot->twsk_prot->twsk_slab_name);
2573out_free_request_sock_slab:
2574	if (prot->rsk_prot && prot->rsk_prot->slab) {
2575		kmem_cache_destroy(prot->rsk_prot->slab);
2576		prot->rsk_prot->slab = NULL;
2577	}
2578out_free_request_sock_slab_name:
2579	if (prot->rsk_prot)
2580		kfree(prot->rsk_prot->slab_name);
2581out_free_sock_slab:
2582	kmem_cache_destroy(prot->slab);
2583	prot->slab = NULL;
2584out:
2585	return -ENOBUFS;
2586}
2587EXPORT_SYMBOL(proto_register);
2588
2589void proto_unregister(struct proto *prot)
2590{
2591	mutex_lock(&proto_list_mutex);
2592	release_proto_idx(prot);
2593	list_del(&prot->node);
2594	mutex_unlock(&proto_list_mutex);
2595
2596	if (prot->slab != NULL) {
2597		kmem_cache_destroy(prot->slab);
2598		prot->slab = NULL;
2599	}
2600
2601	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2602		kmem_cache_destroy(prot->rsk_prot->slab);
2603		kfree(prot->rsk_prot->slab_name);
2604		prot->rsk_prot->slab = NULL;
2605	}
2606
2607	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2608		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2609		kfree(prot->twsk_prot->twsk_slab_name);
2610		prot->twsk_prot->twsk_slab = NULL;
2611	}
2612}
2613EXPORT_SYMBOL(proto_unregister);
2614
2615#ifdef CONFIG_PROC_FS
2616static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2617	__acquires(proto_list_mutex)
2618{
2619	mutex_lock(&proto_list_mutex);
2620	return seq_list_start_head(&proto_list, *pos);
2621}
2622
2623static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2624{
2625	return seq_list_next(v, &proto_list, pos);
2626}
2627
2628static void proto_seq_stop(struct seq_file *seq, void *v)
2629	__releases(proto_list_mutex)
2630{
2631	mutex_unlock(&proto_list_mutex);
2632}
2633
2634static char proto_method_implemented(const void *method)
2635{
2636	return method == NULL ? 'n' : 'y';
2637}
2638static long sock_prot_memory_allocated(struct proto *proto)
2639{
2640	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2641}
2642
2643static char *sock_prot_memory_pressure(struct proto *proto)
2644{
2645	return proto->memory_pressure != NULL ?
2646	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2647}
2648
2649static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2650{
2651
2652	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
2653			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2654		   proto->name,
2655		   proto->obj_size,
2656		   sock_prot_inuse_get(seq_file_net(seq), proto),
2657		   sock_prot_memory_allocated(proto),
2658		   sock_prot_memory_pressure(proto),
2659		   proto->max_header,
2660		   proto->slab == NULL ? "no" : "yes",
2661		   module_name(proto->owner),
2662		   proto_method_implemented(proto->close),
2663		   proto_method_implemented(proto->connect),
2664		   proto_method_implemented(proto->disconnect),
2665		   proto_method_implemented(proto->accept),
2666		   proto_method_implemented(proto->ioctl),
2667		   proto_method_implemented(proto->init),
2668		   proto_method_implemented(proto->destroy),
2669		   proto_method_implemented(proto->shutdown),
2670		   proto_method_implemented(proto->setsockopt),
2671		   proto_method_implemented(proto->getsockopt),
2672		   proto_method_implemented(proto->sendmsg),
2673		   proto_method_implemented(proto->recvmsg),
2674		   proto_method_implemented(proto->sendpage),
2675		   proto_method_implemented(proto->bind),
2676		   proto_method_implemented(proto->backlog_rcv),
2677		   proto_method_implemented(proto->hash),
2678		   proto_method_implemented(proto->unhash),
2679		   proto_method_implemented(proto->get_port),
2680		   proto_method_implemented(proto->enter_memory_pressure));
2681}
2682
2683static int proto_seq_show(struct seq_file *seq, void *v)
2684{
2685	if (v == &proto_list)
2686		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2687			   "protocol",
2688			   "size",
2689			   "sockets",
2690			   "memory",
2691			   "press",
2692			   "maxhdr",
2693			   "slab",
2694			   "module",
2695			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2696	else
2697		proto_seq_printf(seq, list_entry(v, struct proto, node));
2698	return 0;
2699}
2700
2701static const struct seq_operations proto_seq_ops = {
2702	.start  = proto_seq_start,
2703	.next   = proto_seq_next,
2704	.stop   = proto_seq_stop,
2705	.show   = proto_seq_show,
2706};
2707
2708static int proto_seq_open(struct inode *inode, struct file *file)
2709{
2710	return seq_open_net(inode, file, &proto_seq_ops,
2711			    sizeof(struct seq_net_private));
2712}
2713
2714static const struct file_operations proto_seq_fops = {
2715	.owner		= THIS_MODULE,
2716	.open		= proto_seq_open,
2717	.read		= seq_read,
2718	.llseek		= seq_lseek,
2719	.release	= seq_release_net,
2720};
2721
2722static __net_init int proto_init_net(struct net *net)
2723{
2724	if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2725		return -ENOMEM;
2726
2727	return 0;
2728}
2729
2730static __net_exit void proto_exit_net(struct net *net)
2731{
2732	proc_net_remove(net, "protocols");
2733}
2734
2735
2736static __net_initdata struct pernet_operations proto_net_ops = {
2737	.init = proto_init_net,
2738	.exit = proto_exit_net,
2739};
2740
2741static int __init proto_init(void)
2742{
2743	return register_pernet_subsys(&proto_net_ops);
2744}
2745
2746subsys_initcall(proto_init);
2747
2748#endif /* PROC_FS */
2749