sock.c revision e2bcabec6ea5ba30dd2097dc1566e9957d14117c
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_munged(current_ns, cred->euid);
872		ucred->gid = from_kgid_munged(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 != 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
1467/*
1468 *	Simple resource managers for sockets.
1469 */
1470
1471
1472/*
1473 * Write buffer destructor automatically called from kfree_skb.
1474 */
1475void sock_wfree(struct sk_buff *skb)
1476{
1477	struct sock *sk = skb->sk;
1478	unsigned int len = skb->truesize;
1479
1480	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1481		/*
1482		 * Keep a reference on sk_wmem_alloc, this will be released
1483		 * after sk_write_space() call
1484		 */
1485		atomic_sub(len - 1, &sk->sk_wmem_alloc);
1486		sk->sk_write_space(sk);
1487		len = 1;
1488	}
1489	/*
1490	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1491	 * could not do because of in-flight packets
1492	 */
1493	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1494		__sk_free(sk);
1495}
1496EXPORT_SYMBOL(sock_wfree);
1497
1498/*
1499 * Read buffer destructor automatically called from kfree_skb.
1500 */
1501void sock_rfree(struct sk_buff *skb)
1502{
1503	struct sock *sk = skb->sk;
1504	unsigned int len = skb->truesize;
1505
1506	atomic_sub(len, &sk->sk_rmem_alloc);
1507	sk_mem_uncharge(sk, len);
1508}
1509EXPORT_SYMBOL(sock_rfree);
1510
1511void sock_edemux(struct sk_buff *skb)
1512{
1513	struct sock *sk = skb->sk;
1514
1515#ifdef CONFIG_INET
1516	if (sk->sk_state == TCP_TIME_WAIT)
1517		inet_twsk_put(inet_twsk(sk));
1518	else
1519#endif
1520		sock_put(sk);
1521}
1522EXPORT_SYMBOL(sock_edemux);
1523
1524kuid_t sock_i_uid(struct sock *sk)
1525{
1526	kuid_t uid;
1527
1528	read_lock_bh(&sk->sk_callback_lock);
1529	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1530	read_unlock_bh(&sk->sk_callback_lock);
1531	return uid;
1532}
1533EXPORT_SYMBOL(sock_i_uid);
1534
1535unsigned long sock_i_ino(struct sock *sk)
1536{
1537	unsigned long ino;
1538
1539	read_lock_bh(&sk->sk_callback_lock);
1540	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1541	read_unlock_bh(&sk->sk_callback_lock);
1542	return ino;
1543}
1544EXPORT_SYMBOL(sock_i_ino);
1545
1546/*
1547 * Allocate a skb from the socket's send buffer.
1548 */
1549struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1550			     gfp_t priority)
1551{
1552	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1553		struct sk_buff *skb = alloc_skb(size, priority);
1554		if (skb) {
1555			skb_set_owner_w(skb, sk);
1556			return skb;
1557		}
1558	}
1559	return NULL;
1560}
1561EXPORT_SYMBOL(sock_wmalloc);
1562
1563/*
1564 * Allocate a skb from the socket's receive buffer.
1565 */
1566struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1567			     gfp_t priority)
1568{
1569	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1570		struct sk_buff *skb = alloc_skb(size, priority);
1571		if (skb) {
1572			skb_set_owner_r(skb, sk);
1573			return skb;
1574		}
1575	}
1576	return NULL;
1577}
1578
1579/*
1580 * Allocate a memory block from the socket's option memory buffer.
1581 */
1582void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1583{
1584	if ((unsigned int)size <= sysctl_optmem_max &&
1585	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1586		void *mem;
1587		/* First do the add, to avoid the race if kmalloc
1588		 * might sleep.
1589		 */
1590		atomic_add(size, &sk->sk_omem_alloc);
1591		mem = kmalloc(size, priority);
1592		if (mem)
1593			return mem;
1594		atomic_sub(size, &sk->sk_omem_alloc);
1595	}
1596	return NULL;
1597}
1598EXPORT_SYMBOL(sock_kmalloc);
1599
1600/*
1601 * Free an option memory block.
1602 */
1603void sock_kfree_s(struct sock *sk, void *mem, int size)
1604{
1605	kfree(mem);
1606	atomic_sub(size, &sk->sk_omem_alloc);
1607}
1608EXPORT_SYMBOL(sock_kfree_s);
1609
1610/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1611   I think, these locks should be removed for datagram sockets.
1612 */
1613static long sock_wait_for_wmem(struct sock *sk, long timeo)
1614{
1615	DEFINE_WAIT(wait);
1616
1617	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1618	for (;;) {
1619		if (!timeo)
1620			break;
1621		if (signal_pending(current))
1622			break;
1623		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1624		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1625		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1626			break;
1627		if (sk->sk_shutdown & SEND_SHUTDOWN)
1628			break;
1629		if (sk->sk_err)
1630			break;
1631		timeo = schedule_timeout(timeo);
1632	}
1633	finish_wait(sk_sleep(sk), &wait);
1634	return timeo;
1635}
1636
1637
1638/*
1639 *	Generic send/receive buffer handlers
1640 */
1641
1642struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1643				     unsigned long data_len, int noblock,
1644				     int *errcode)
1645{
1646	struct sk_buff *skb;
1647	gfp_t gfp_mask;
1648	long timeo;
1649	int err;
1650	int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1651
1652	err = -EMSGSIZE;
1653	if (npages > MAX_SKB_FRAGS)
1654		goto failure;
1655
1656	gfp_mask = sk->sk_allocation;
1657	if (gfp_mask & __GFP_WAIT)
1658		gfp_mask |= __GFP_REPEAT;
1659
1660	timeo = sock_sndtimeo(sk, noblock);
1661	while (1) {
1662		err = sock_error(sk);
1663		if (err != 0)
1664			goto failure;
1665
1666		err = -EPIPE;
1667		if (sk->sk_shutdown & SEND_SHUTDOWN)
1668			goto failure;
1669
1670		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1671			skb = alloc_skb(header_len, gfp_mask);
1672			if (skb) {
1673				int i;
1674
1675				/* No pages, we're done... */
1676				if (!data_len)
1677					break;
1678
1679				skb->truesize += data_len;
1680				skb_shinfo(skb)->nr_frags = npages;
1681				for (i = 0; i < npages; i++) {
1682					struct page *page;
1683
1684					page = alloc_pages(sk->sk_allocation, 0);
1685					if (!page) {
1686						err = -ENOBUFS;
1687						skb_shinfo(skb)->nr_frags = i;
1688						kfree_skb(skb);
1689						goto failure;
1690					}
1691
1692					__skb_fill_page_desc(skb, i,
1693							page, 0,
1694							(data_len >= PAGE_SIZE ?
1695							 PAGE_SIZE :
1696							 data_len));
1697					data_len -= PAGE_SIZE;
1698				}
1699
1700				/* Full success... */
1701				break;
1702			}
1703			err = -ENOBUFS;
1704			goto failure;
1705		}
1706		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1707		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1708		err = -EAGAIN;
1709		if (!timeo)
1710			goto failure;
1711		if (signal_pending(current))
1712			goto interrupted;
1713		timeo = sock_wait_for_wmem(sk, timeo);
1714	}
1715
1716	skb_set_owner_w(skb, sk);
1717	return skb;
1718
1719interrupted:
1720	err = sock_intr_errno(timeo);
1721failure:
1722	*errcode = err;
1723	return NULL;
1724}
1725EXPORT_SYMBOL(sock_alloc_send_pskb);
1726
1727struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1728				    int noblock, int *errcode)
1729{
1730	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1731}
1732EXPORT_SYMBOL(sock_alloc_send_skb);
1733
1734/* On 32bit arches, an skb frag is limited to 2^15 */
1735#define SKB_FRAG_PAGE_ORDER	get_order(32768)
1736
1737bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
1738{
1739	int order;
1740
1741	if (pfrag->page) {
1742		if (atomic_read(&pfrag->page->_count) == 1) {
1743			pfrag->offset = 0;
1744			return true;
1745		}
1746		if (pfrag->offset < pfrag->size)
1747			return true;
1748		put_page(pfrag->page);
1749	}
1750
1751	/* We restrict high order allocations to users that can afford to wait */
1752	order = (sk->sk_allocation & __GFP_WAIT) ? SKB_FRAG_PAGE_ORDER : 0;
1753
1754	do {
1755		gfp_t gfp = sk->sk_allocation;
1756
1757		if (order)
1758			gfp |= __GFP_COMP | __GFP_NOWARN;
1759		pfrag->page = alloc_pages(gfp, order);
1760		if (likely(pfrag->page)) {
1761			pfrag->offset = 0;
1762			pfrag->size = PAGE_SIZE << order;
1763			return true;
1764		}
1765	} while (--order >= 0);
1766
1767	sk_enter_memory_pressure(sk);
1768	sk_stream_moderate_sndbuf(sk);
1769	return false;
1770}
1771EXPORT_SYMBOL(sk_page_frag_refill);
1772
1773static void __lock_sock(struct sock *sk)
1774	__releases(&sk->sk_lock.slock)
1775	__acquires(&sk->sk_lock.slock)
1776{
1777	DEFINE_WAIT(wait);
1778
1779	for (;;) {
1780		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1781					TASK_UNINTERRUPTIBLE);
1782		spin_unlock_bh(&sk->sk_lock.slock);
1783		schedule();
1784		spin_lock_bh(&sk->sk_lock.slock);
1785		if (!sock_owned_by_user(sk))
1786			break;
1787	}
1788	finish_wait(&sk->sk_lock.wq, &wait);
1789}
1790
1791static void __release_sock(struct sock *sk)
1792	__releases(&sk->sk_lock.slock)
1793	__acquires(&sk->sk_lock.slock)
1794{
1795	struct sk_buff *skb = sk->sk_backlog.head;
1796
1797	do {
1798		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1799		bh_unlock_sock(sk);
1800
1801		do {
1802			struct sk_buff *next = skb->next;
1803
1804			prefetch(next);
1805			WARN_ON_ONCE(skb_dst_is_noref(skb));
1806			skb->next = NULL;
1807			sk_backlog_rcv(sk, skb);
1808
1809			/*
1810			 * We are in process context here with softirqs
1811			 * disabled, use cond_resched_softirq() to preempt.
1812			 * This is safe to do because we've taken the backlog
1813			 * queue private:
1814			 */
1815			cond_resched_softirq();
1816
1817			skb = next;
1818		} while (skb != NULL);
1819
1820		bh_lock_sock(sk);
1821	} while ((skb = sk->sk_backlog.head) != NULL);
1822
1823	/*
1824	 * Doing the zeroing here guarantee we can not loop forever
1825	 * while a wild producer attempts to flood us.
1826	 */
1827	sk->sk_backlog.len = 0;
1828}
1829
1830/**
1831 * sk_wait_data - wait for data to arrive at sk_receive_queue
1832 * @sk:    sock to wait on
1833 * @timeo: for how long
1834 *
1835 * Now socket state including sk->sk_err is changed only under lock,
1836 * hence we may omit checks after joining wait queue.
1837 * We check receive queue before schedule() only as optimization;
1838 * it is very likely that release_sock() added new data.
1839 */
1840int sk_wait_data(struct sock *sk, long *timeo)
1841{
1842	int rc;
1843	DEFINE_WAIT(wait);
1844
1845	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1846	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1847	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1848	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1849	finish_wait(sk_sleep(sk), &wait);
1850	return rc;
1851}
1852EXPORT_SYMBOL(sk_wait_data);
1853
1854/**
1855 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1856 *	@sk: socket
1857 *	@size: memory size to allocate
1858 *	@kind: allocation type
1859 *
1860 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1861 *	rmem allocation. This function assumes that protocols which have
1862 *	memory_pressure use sk_wmem_queued as write buffer accounting.
1863 */
1864int __sk_mem_schedule(struct sock *sk, int size, int kind)
1865{
1866	struct proto *prot = sk->sk_prot;
1867	int amt = sk_mem_pages(size);
1868	long allocated;
1869	int parent_status = UNDER_LIMIT;
1870
1871	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1872
1873	allocated = sk_memory_allocated_add(sk, amt, &parent_status);
1874
1875	/* Under limit. */
1876	if (parent_status == UNDER_LIMIT &&
1877			allocated <= sk_prot_mem_limits(sk, 0)) {
1878		sk_leave_memory_pressure(sk);
1879		return 1;
1880	}
1881
1882	/* Under pressure. (we or our parents) */
1883	if ((parent_status > SOFT_LIMIT) ||
1884			allocated > sk_prot_mem_limits(sk, 1))
1885		sk_enter_memory_pressure(sk);
1886
1887	/* Over hard limit (we or our parents) */
1888	if ((parent_status == OVER_LIMIT) ||
1889			(allocated > sk_prot_mem_limits(sk, 2)))
1890		goto suppress_allocation;
1891
1892	/* guarantee minimum buffer size under pressure */
1893	if (kind == SK_MEM_RECV) {
1894		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1895			return 1;
1896
1897	} else { /* SK_MEM_SEND */
1898		if (sk->sk_type == SOCK_STREAM) {
1899			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1900				return 1;
1901		} else if (atomic_read(&sk->sk_wmem_alloc) <
1902			   prot->sysctl_wmem[0])
1903				return 1;
1904	}
1905
1906	if (sk_has_memory_pressure(sk)) {
1907		int alloc;
1908
1909		if (!sk_under_memory_pressure(sk))
1910			return 1;
1911		alloc = sk_sockets_allocated_read_positive(sk);
1912		if (sk_prot_mem_limits(sk, 2) > alloc *
1913		    sk_mem_pages(sk->sk_wmem_queued +
1914				 atomic_read(&sk->sk_rmem_alloc) +
1915				 sk->sk_forward_alloc))
1916			return 1;
1917	}
1918
1919suppress_allocation:
1920
1921	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1922		sk_stream_moderate_sndbuf(sk);
1923
1924		/* Fail only if socket is _under_ its sndbuf.
1925		 * In this case we cannot block, so that we have to fail.
1926		 */
1927		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1928			return 1;
1929	}
1930
1931	trace_sock_exceed_buf_limit(sk, prot, allocated);
1932
1933	/* Alas. Undo changes. */
1934	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1935
1936	sk_memory_allocated_sub(sk, amt);
1937
1938	return 0;
1939}
1940EXPORT_SYMBOL(__sk_mem_schedule);
1941
1942/**
1943 *	__sk_reclaim - reclaim memory_allocated
1944 *	@sk: socket
1945 */
1946void __sk_mem_reclaim(struct sock *sk)
1947{
1948	sk_memory_allocated_sub(sk,
1949				sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT);
1950	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1951
1952	if (sk_under_memory_pressure(sk) &&
1953	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
1954		sk_leave_memory_pressure(sk);
1955}
1956EXPORT_SYMBOL(__sk_mem_reclaim);
1957
1958
1959/*
1960 * Set of default routines for initialising struct proto_ops when
1961 * the protocol does not support a particular function. In certain
1962 * cases where it makes no sense for a protocol to have a "do nothing"
1963 * function, some default processing is provided.
1964 */
1965
1966int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1967{
1968	return -EOPNOTSUPP;
1969}
1970EXPORT_SYMBOL(sock_no_bind);
1971
1972int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1973		    int len, int flags)
1974{
1975	return -EOPNOTSUPP;
1976}
1977EXPORT_SYMBOL(sock_no_connect);
1978
1979int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1980{
1981	return -EOPNOTSUPP;
1982}
1983EXPORT_SYMBOL(sock_no_socketpair);
1984
1985int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1986{
1987	return -EOPNOTSUPP;
1988}
1989EXPORT_SYMBOL(sock_no_accept);
1990
1991int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1992		    int *len, int peer)
1993{
1994	return -EOPNOTSUPP;
1995}
1996EXPORT_SYMBOL(sock_no_getname);
1997
1998unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1999{
2000	return 0;
2001}
2002EXPORT_SYMBOL(sock_no_poll);
2003
2004int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2005{
2006	return -EOPNOTSUPP;
2007}
2008EXPORT_SYMBOL(sock_no_ioctl);
2009
2010int sock_no_listen(struct socket *sock, int backlog)
2011{
2012	return -EOPNOTSUPP;
2013}
2014EXPORT_SYMBOL(sock_no_listen);
2015
2016int sock_no_shutdown(struct socket *sock, int how)
2017{
2018	return -EOPNOTSUPP;
2019}
2020EXPORT_SYMBOL(sock_no_shutdown);
2021
2022int sock_no_setsockopt(struct socket *sock, int level, int optname,
2023		    char __user *optval, unsigned int optlen)
2024{
2025	return -EOPNOTSUPP;
2026}
2027EXPORT_SYMBOL(sock_no_setsockopt);
2028
2029int sock_no_getsockopt(struct socket *sock, int level, int optname,
2030		    char __user *optval, int __user *optlen)
2031{
2032	return -EOPNOTSUPP;
2033}
2034EXPORT_SYMBOL(sock_no_getsockopt);
2035
2036int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2037		    size_t len)
2038{
2039	return -EOPNOTSUPP;
2040}
2041EXPORT_SYMBOL(sock_no_sendmsg);
2042
2043int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2044		    size_t len, int flags)
2045{
2046	return -EOPNOTSUPP;
2047}
2048EXPORT_SYMBOL(sock_no_recvmsg);
2049
2050int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2051{
2052	/* Mirror missing mmap method error code */
2053	return -ENODEV;
2054}
2055EXPORT_SYMBOL(sock_no_mmap);
2056
2057ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2058{
2059	ssize_t res;
2060	struct msghdr msg = {.msg_flags = flags};
2061	struct kvec iov;
2062	char *kaddr = kmap(page);
2063	iov.iov_base = kaddr + offset;
2064	iov.iov_len = size;
2065	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2066	kunmap(page);
2067	return res;
2068}
2069EXPORT_SYMBOL(sock_no_sendpage);
2070
2071/*
2072 *	Default Socket Callbacks
2073 */
2074
2075static void sock_def_wakeup(struct sock *sk)
2076{
2077	struct socket_wq *wq;
2078
2079	rcu_read_lock();
2080	wq = rcu_dereference(sk->sk_wq);
2081	if (wq_has_sleeper(wq))
2082		wake_up_interruptible_all(&wq->wait);
2083	rcu_read_unlock();
2084}
2085
2086static void sock_def_error_report(struct sock *sk)
2087{
2088	struct socket_wq *wq;
2089
2090	rcu_read_lock();
2091	wq = rcu_dereference(sk->sk_wq);
2092	if (wq_has_sleeper(wq))
2093		wake_up_interruptible_poll(&wq->wait, POLLERR);
2094	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2095	rcu_read_unlock();
2096}
2097
2098static void sock_def_readable(struct sock *sk, int len)
2099{
2100	struct socket_wq *wq;
2101
2102	rcu_read_lock();
2103	wq = rcu_dereference(sk->sk_wq);
2104	if (wq_has_sleeper(wq))
2105		wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2106						POLLRDNORM | POLLRDBAND);
2107	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2108	rcu_read_unlock();
2109}
2110
2111static void sock_def_write_space(struct sock *sk)
2112{
2113	struct socket_wq *wq;
2114
2115	rcu_read_lock();
2116
2117	/* Do not wake up a writer until he can make "significant"
2118	 * progress.  --DaveM
2119	 */
2120	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2121		wq = rcu_dereference(sk->sk_wq);
2122		if (wq_has_sleeper(wq))
2123			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2124						POLLWRNORM | POLLWRBAND);
2125
2126		/* Should agree with poll, otherwise some programs break */
2127		if (sock_writeable(sk))
2128			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2129	}
2130
2131	rcu_read_unlock();
2132}
2133
2134static void sock_def_destruct(struct sock *sk)
2135{
2136	kfree(sk->sk_protinfo);
2137}
2138
2139void sk_send_sigurg(struct sock *sk)
2140{
2141	if (sk->sk_socket && sk->sk_socket->file)
2142		if (send_sigurg(&sk->sk_socket->file->f_owner))
2143			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2144}
2145EXPORT_SYMBOL(sk_send_sigurg);
2146
2147void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2148		    unsigned long expires)
2149{
2150	if (!mod_timer(timer, expires))
2151		sock_hold(sk);
2152}
2153EXPORT_SYMBOL(sk_reset_timer);
2154
2155void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2156{
2157	if (timer_pending(timer) && del_timer(timer))
2158		__sock_put(sk);
2159}
2160EXPORT_SYMBOL(sk_stop_timer);
2161
2162void sock_init_data(struct socket *sock, struct sock *sk)
2163{
2164	skb_queue_head_init(&sk->sk_receive_queue);
2165	skb_queue_head_init(&sk->sk_write_queue);
2166	skb_queue_head_init(&sk->sk_error_queue);
2167#ifdef CONFIG_NET_DMA
2168	skb_queue_head_init(&sk->sk_async_wait_queue);
2169#endif
2170
2171	sk->sk_send_head	=	NULL;
2172
2173	init_timer(&sk->sk_timer);
2174
2175	sk->sk_allocation	=	GFP_KERNEL;
2176	sk->sk_rcvbuf		=	sysctl_rmem_default;
2177	sk->sk_sndbuf		=	sysctl_wmem_default;
2178	sk->sk_state		=	TCP_CLOSE;
2179	sk_set_socket(sk, sock);
2180
2181	sock_set_flag(sk, SOCK_ZAPPED);
2182
2183	if (sock) {
2184		sk->sk_type	=	sock->type;
2185		sk->sk_wq	=	sock->wq;
2186		sock->sk	=	sk;
2187	} else
2188		sk->sk_wq	=	NULL;
2189
2190	spin_lock_init(&sk->sk_dst_lock);
2191	rwlock_init(&sk->sk_callback_lock);
2192	lockdep_set_class_and_name(&sk->sk_callback_lock,
2193			af_callback_keys + sk->sk_family,
2194			af_family_clock_key_strings[sk->sk_family]);
2195
2196	sk->sk_state_change	=	sock_def_wakeup;
2197	sk->sk_data_ready	=	sock_def_readable;
2198	sk->sk_write_space	=	sock_def_write_space;
2199	sk->sk_error_report	=	sock_def_error_report;
2200	sk->sk_destruct		=	sock_def_destruct;
2201
2202	sk->sk_frag.page	=	NULL;
2203	sk->sk_frag.offset	=	0;
2204	sk->sk_peek_off		=	-1;
2205
2206	sk->sk_peer_pid 	=	NULL;
2207	sk->sk_peer_cred	=	NULL;
2208	sk->sk_write_pending	=	0;
2209	sk->sk_rcvlowat		=	1;
2210	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2211	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2212
2213	sk->sk_stamp = ktime_set(-1L, 0);
2214
2215	/*
2216	 * Before updating sk_refcnt, we must commit prior changes to memory
2217	 * (Documentation/RCU/rculist_nulls.txt for details)
2218	 */
2219	smp_wmb();
2220	atomic_set(&sk->sk_refcnt, 1);
2221	atomic_set(&sk->sk_drops, 0);
2222}
2223EXPORT_SYMBOL(sock_init_data);
2224
2225void lock_sock_nested(struct sock *sk, int subclass)
2226{
2227	might_sleep();
2228	spin_lock_bh(&sk->sk_lock.slock);
2229	if (sk->sk_lock.owned)
2230		__lock_sock(sk);
2231	sk->sk_lock.owned = 1;
2232	spin_unlock(&sk->sk_lock.slock);
2233	/*
2234	 * The sk_lock has mutex_lock() semantics here:
2235	 */
2236	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2237	local_bh_enable();
2238}
2239EXPORT_SYMBOL(lock_sock_nested);
2240
2241void release_sock(struct sock *sk)
2242{
2243	/*
2244	 * The sk_lock has mutex_unlock() semantics:
2245	 */
2246	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2247
2248	spin_lock_bh(&sk->sk_lock.slock);
2249	if (sk->sk_backlog.tail)
2250		__release_sock(sk);
2251
2252	if (sk->sk_prot->release_cb)
2253		sk->sk_prot->release_cb(sk);
2254
2255	sk->sk_lock.owned = 0;
2256	if (waitqueue_active(&sk->sk_lock.wq))
2257		wake_up(&sk->sk_lock.wq);
2258	spin_unlock_bh(&sk->sk_lock.slock);
2259}
2260EXPORT_SYMBOL(release_sock);
2261
2262/**
2263 * lock_sock_fast - fast version of lock_sock
2264 * @sk: socket
2265 *
2266 * This version should be used for very small section, where process wont block
2267 * return false if fast path is taken
2268 *   sk_lock.slock locked, owned = 0, BH disabled
2269 * return true if slow path is taken
2270 *   sk_lock.slock unlocked, owned = 1, BH enabled
2271 */
2272bool lock_sock_fast(struct sock *sk)
2273{
2274	might_sleep();
2275	spin_lock_bh(&sk->sk_lock.slock);
2276
2277	if (!sk->sk_lock.owned)
2278		/*
2279		 * Note : We must disable BH
2280		 */
2281		return false;
2282
2283	__lock_sock(sk);
2284	sk->sk_lock.owned = 1;
2285	spin_unlock(&sk->sk_lock.slock);
2286	/*
2287	 * The sk_lock has mutex_lock() semantics here:
2288	 */
2289	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2290	local_bh_enable();
2291	return true;
2292}
2293EXPORT_SYMBOL(lock_sock_fast);
2294
2295int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2296{
2297	struct timeval tv;
2298	if (!sock_flag(sk, SOCK_TIMESTAMP))
2299		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2300	tv = ktime_to_timeval(sk->sk_stamp);
2301	if (tv.tv_sec == -1)
2302		return -ENOENT;
2303	if (tv.tv_sec == 0) {
2304		sk->sk_stamp = ktime_get_real();
2305		tv = ktime_to_timeval(sk->sk_stamp);
2306	}
2307	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2308}
2309EXPORT_SYMBOL(sock_get_timestamp);
2310
2311int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2312{
2313	struct timespec ts;
2314	if (!sock_flag(sk, SOCK_TIMESTAMP))
2315		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2316	ts = ktime_to_timespec(sk->sk_stamp);
2317	if (ts.tv_sec == -1)
2318		return -ENOENT;
2319	if (ts.tv_sec == 0) {
2320		sk->sk_stamp = ktime_get_real();
2321		ts = ktime_to_timespec(sk->sk_stamp);
2322	}
2323	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2324}
2325EXPORT_SYMBOL(sock_get_timestampns);
2326
2327void sock_enable_timestamp(struct sock *sk, int flag)
2328{
2329	if (!sock_flag(sk, flag)) {
2330		unsigned long previous_flags = sk->sk_flags;
2331
2332		sock_set_flag(sk, flag);
2333		/*
2334		 * we just set one of the two flags which require net
2335		 * time stamping, but time stamping might have been on
2336		 * already because of the other one
2337		 */
2338		if (!(previous_flags & SK_FLAGS_TIMESTAMP))
2339			net_enable_timestamp();
2340	}
2341}
2342
2343/*
2344 *	Get a socket option on an socket.
2345 *
2346 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2347 *	asynchronous errors should be reported by getsockopt. We assume
2348 *	this means if you specify SO_ERROR (otherwise whats the point of it).
2349 */
2350int sock_common_getsockopt(struct socket *sock, int level, int optname,
2351			   char __user *optval, int __user *optlen)
2352{
2353	struct sock *sk = sock->sk;
2354
2355	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2356}
2357EXPORT_SYMBOL(sock_common_getsockopt);
2358
2359#ifdef CONFIG_COMPAT
2360int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2361				  char __user *optval, int __user *optlen)
2362{
2363	struct sock *sk = sock->sk;
2364
2365	if (sk->sk_prot->compat_getsockopt != NULL)
2366		return sk->sk_prot->compat_getsockopt(sk, level, optname,
2367						      optval, optlen);
2368	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2369}
2370EXPORT_SYMBOL(compat_sock_common_getsockopt);
2371#endif
2372
2373int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2374			struct msghdr *msg, size_t size, int flags)
2375{
2376	struct sock *sk = sock->sk;
2377	int addr_len = 0;
2378	int err;
2379
2380	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2381				   flags & ~MSG_DONTWAIT, &addr_len);
2382	if (err >= 0)
2383		msg->msg_namelen = addr_len;
2384	return err;
2385}
2386EXPORT_SYMBOL(sock_common_recvmsg);
2387
2388/*
2389 *	Set socket options on an inet socket.
2390 */
2391int sock_common_setsockopt(struct socket *sock, int level, int optname,
2392			   char __user *optval, unsigned int optlen)
2393{
2394	struct sock *sk = sock->sk;
2395
2396	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2397}
2398EXPORT_SYMBOL(sock_common_setsockopt);
2399
2400#ifdef CONFIG_COMPAT
2401int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2402				  char __user *optval, unsigned int optlen)
2403{
2404	struct sock *sk = sock->sk;
2405
2406	if (sk->sk_prot->compat_setsockopt != NULL)
2407		return sk->sk_prot->compat_setsockopt(sk, level, optname,
2408						      optval, optlen);
2409	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2410}
2411EXPORT_SYMBOL(compat_sock_common_setsockopt);
2412#endif
2413
2414void sk_common_release(struct sock *sk)
2415{
2416	if (sk->sk_prot->destroy)
2417		sk->sk_prot->destroy(sk);
2418
2419	/*
2420	 * Observation: when sock_common_release is called, processes have
2421	 * no access to socket. But net still has.
2422	 * Step one, detach it from networking:
2423	 *
2424	 * A. Remove from hash tables.
2425	 */
2426
2427	sk->sk_prot->unhash(sk);
2428
2429	/*
2430	 * In this point socket cannot receive new packets, but it is possible
2431	 * that some packets are in flight because some CPU runs receiver and
2432	 * did hash table lookup before we unhashed socket. They will achieve
2433	 * receive queue and will be purged by socket destructor.
2434	 *
2435	 * Also we still have packets pending on receive queue and probably,
2436	 * our own packets waiting in device queues. sock_destroy will drain
2437	 * receive queue, but transmitted packets will delay socket destruction
2438	 * until the last reference will be released.
2439	 */
2440
2441	sock_orphan(sk);
2442
2443	xfrm_sk_free_policy(sk);
2444
2445	sk_refcnt_debug_release(sk);
2446
2447	if (sk->sk_frag.page) {
2448		put_page(sk->sk_frag.page);
2449		sk->sk_frag.page = NULL;
2450	}
2451
2452	sock_put(sk);
2453}
2454EXPORT_SYMBOL(sk_common_release);
2455
2456#ifdef CONFIG_PROC_FS
2457#define PROTO_INUSE_NR	64	/* should be enough for the first time */
2458struct prot_inuse {
2459	int val[PROTO_INUSE_NR];
2460};
2461
2462static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2463
2464#ifdef CONFIG_NET_NS
2465void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2466{
2467	__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2468}
2469EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2470
2471int sock_prot_inuse_get(struct net *net, struct proto *prot)
2472{
2473	int cpu, idx = prot->inuse_idx;
2474	int res = 0;
2475
2476	for_each_possible_cpu(cpu)
2477		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2478
2479	return res >= 0 ? res : 0;
2480}
2481EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2482
2483static int __net_init sock_inuse_init_net(struct net *net)
2484{
2485	net->core.inuse = alloc_percpu(struct prot_inuse);
2486	return net->core.inuse ? 0 : -ENOMEM;
2487}
2488
2489static void __net_exit sock_inuse_exit_net(struct net *net)
2490{
2491	free_percpu(net->core.inuse);
2492}
2493
2494static struct pernet_operations net_inuse_ops = {
2495	.init = sock_inuse_init_net,
2496	.exit = sock_inuse_exit_net,
2497};
2498
2499static __init int net_inuse_init(void)
2500{
2501	if (register_pernet_subsys(&net_inuse_ops))
2502		panic("Cannot initialize net inuse counters");
2503
2504	return 0;
2505}
2506
2507core_initcall(net_inuse_init);
2508#else
2509static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2510
2511void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2512{
2513	__this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2514}
2515EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2516
2517int sock_prot_inuse_get(struct net *net, struct proto *prot)
2518{
2519	int cpu, idx = prot->inuse_idx;
2520	int res = 0;
2521
2522	for_each_possible_cpu(cpu)
2523		res += per_cpu(prot_inuse, cpu).val[idx];
2524
2525	return res >= 0 ? res : 0;
2526}
2527EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2528#endif
2529
2530static void assign_proto_idx(struct proto *prot)
2531{
2532	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2533
2534	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2535		pr_err("PROTO_INUSE_NR exhausted\n");
2536		return;
2537	}
2538
2539	set_bit(prot->inuse_idx, proto_inuse_idx);
2540}
2541
2542static void release_proto_idx(struct proto *prot)
2543{
2544	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2545		clear_bit(prot->inuse_idx, proto_inuse_idx);
2546}
2547#else
2548static inline void assign_proto_idx(struct proto *prot)
2549{
2550}
2551
2552static inline void release_proto_idx(struct proto *prot)
2553{
2554}
2555#endif
2556
2557int proto_register(struct proto *prot, int alloc_slab)
2558{
2559	if (alloc_slab) {
2560		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2561					SLAB_HWCACHE_ALIGN | prot->slab_flags,
2562					NULL);
2563
2564		if (prot->slab == NULL) {
2565			pr_crit("%s: Can't create sock SLAB cache!\n",
2566				prot->name);
2567			goto out;
2568		}
2569
2570		if (prot->rsk_prot != NULL) {
2571			prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2572			if (prot->rsk_prot->slab_name == NULL)
2573				goto out_free_sock_slab;
2574
2575			prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2576								 prot->rsk_prot->obj_size, 0,
2577								 SLAB_HWCACHE_ALIGN, NULL);
2578
2579			if (prot->rsk_prot->slab == NULL) {
2580				pr_crit("%s: Can't create request sock SLAB cache!\n",
2581					prot->name);
2582				goto out_free_request_sock_slab_name;
2583			}
2584		}
2585
2586		if (prot->twsk_prot != NULL) {
2587			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2588
2589			if (prot->twsk_prot->twsk_slab_name == NULL)
2590				goto out_free_request_sock_slab;
2591
2592			prot->twsk_prot->twsk_slab =
2593				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2594						  prot->twsk_prot->twsk_obj_size,
2595						  0,
2596						  SLAB_HWCACHE_ALIGN |
2597							prot->slab_flags,
2598						  NULL);
2599			if (prot->twsk_prot->twsk_slab == NULL)
2600				goto out_free_timewait_sock_slab_name;
2601		}
2602	}
2603
2604	mutex_lock(&proto_list_mutex);
2605	list_add(&prot->node, &proto_list);
2606	assign_proto_idx(prot);
2607	mutex_unlock(&proto_list_mutex);
2608	return 0;
2609
2610out_free_timewait_sock_slab_name:
2611	kfree(prot->twsk_prot->twsk_slab_name);
2612out_free_request_sock_slab:
2613	if (prot->rsk_prot && prot->rsk_prot->slab) {
2614		kmem_cache_destroy(prot->rsk_prot->slab);
2615		prot->rsk_prot->slab = NULL;
2616	}
2617out_free_request_sock_slab_name:
2618	if (prot->rsk_prot)
2619		kfree(prot->rsk_prot->slab_name);
2620out_free_sock_slab:
2621	kmem_cache_destroy(prot->slab);
2622	prot->slab = NULL;
2623out:
2624	return -ENOBUFS;
2625}
2626EXPORT_SYMBOL(proto_register);
2627
2628void proto_unregister(struct proto *prot)
2629{
2630	mutex_lock(&proto_list_mutex);
2631	release_proto_idx(prot);
2632	list_del(&prot->node);
2633	mutex_unlock(&proto_list_mutex);
2634
2635	if (prot->slab != NULL) {
2636		kmem_cache_destroy(prot->slab);
2637		prot->slab = NULL;
2638	}
2639
2640	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2641		kmem_cache_destroy(prot->rsk_prot->slab);
2642		kfree(prot->rsk_prot->slab_name);
2643		prot->rsk_prot->slab = NULL;
2644	}
2645
2646	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2647		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2648		kfree(prot->twsk_prot->twsk_slab_name);
2649		prot->twsk_prot->twsk_slab = NULL;
2650	}
2651}
2652EXPORT_SYMBOL(proto_unregister);
2653
2654#ifdef CONFIG_PROC_FS
2655static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2656	__acquires(proto_list_mutex)
2657{
2658	mutex_lock(&proto_list_mutex);
2659	return seq_list_start_head(&proto_list, *pos);
2660}
2661
2662static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2663{
2664	return seq_list_next(v, &proto_list, pos);
2665}
2666
2667static void proto_seq_stop(struct seq_file *seq, void *v)
2668	__releases(proto_list_mutex)
2669{
2670	mutex_unlock(&proto_list_mutex);
2671}
2672
2673static char proto_method_implemented(const void *method)
2674{
2675	return method == NULL ? 'n' : 'y';
2676}
2677static long sock_prot_memory_allocated(struct proto *proto)
2678{
2679	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2680}
2681
2682static char *sock_prot_memory_pressure(struct proto *proto)
2683{
2684	return proto->memory_pressure != NULL ?
2685	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2686}
2687
2688static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2689{
2690
2691	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
2692			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2693		   proto->name,
2694		   proto->obj_size,
2695		   sock_prot_inuse_get(seq_file_net(seq), proto),
2696		   sock_prot_memory_allocated(proto),
2697		   sock_prot_memory_pressure(proto),
2698		   proto->max_header,
2699		   proto->slab == NULL ? "no" : "yes",
2700		   module_name(proto->owner),
2701		   proto_method_implemented(proto->close),
2702		   proto_method_implemented(proto->connect),
2703		   proto_method_implemented(proto->disconnect),
2704		   proto_method_implemented(proto->accept),
2705		   proto_method_implemented(proto->ioctl),
2706		   proto_method_implemented(proto->init),
2707		   proto_method_implemented(proto->destroy),
2708		   proto_method_implemented(proto->shutdown),
2709		   proto_method_implemented(proto->setsockopt),
2710		   proto_method_implemented(proto->getsockopt),
2711		   proto_method_implemented(proto->sendmsg),
2712		   proto_method_implemented(proto->recvmsg),
2713		   proto_method_implemented(proto->sendpage),
2714		   proto_method_implemented(proto->bind),
2715		   proto_method_implemented(proto->backlog_rcv),
2716		   proto_method_implemented(proto->hash),
2717		   proto_method_implemented(proto->unhash),
2718		   proto_method_implemented(proto->get_port),
2719		   proto_method_implemented(proto->enter_memory_pressure));
2720}
2721
2722static int proto_seq_show(struct seq_file *seq, void *v)
2723{
2724	if (v == &proto_list)
2725		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2726			   "protocol",
2727			   "size",
2728			   "sockets",
2729			   "memory",
2730			   "press",
2731			   "maxhdr",
2732			   "slab",
2733			   "module",
2734			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2735	else
2736		proto_seq_printf(seq, list_entry(v, struct proto, node));
2737	return 0;
2738}
2739
2740static const struct seq_operations proto_seq_ops = {
2741	.start  = proto_seq_start,
2742	.next   = proto_seq_next,
2743	.stop   = proto_seq_stop,
2744	.show   = proto_seq_show,
2745};
2746
2747static int proto_seq_open(struct inode *inode, struct file *file)
2748{
2749	return seq_open_net(inode, file, &proto_seq_ops,
2750			    sizeof(struct seq_net_private));
2751}
2752
2753static const struct file_operations proto_seq_fops = {
2754	.owner		= THIS_MODULE,
2755	.open		= proto_seq_open,
2756	.read		= seq_read,
2757	.llseek		= seq_lseek,
2758	.release	= seq_release_net,
2759};
2760
2761static __net_init int proto_init_net(struct net *net)
2762{
2763	if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2764		return -ENOMEM;
2765
2766	return 0;
2767}
2768
2769static __net_exit void proto_exit_net(struct net *net)
2770{
2771	proc_net_remove(net, "protocols");
2772}
2773
2774
2775static __net_initdata struct pernet_operations proto_net_ops = {
2776	.init = proto_init_net,
2777	.exit = proto_exit_net,
2778};
2779
2780static int __init proto_init(void)
2781{
2782	return register_pernet_subsys(&proto_net_ops);
2783}
2784
2785subsys_initcall(proto_init);
2786
2787#endif /* PROC_FS */
2788