sock.c revision 8a8e04df4747661daaee77e98e102d99c9e09b98
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
329static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
330{
331	struct timeval tv;
332
333	if (optlen < sizeof(tv))
334		return -EINVAL;
335	if (copy_from_user(&tv, optval, sizeof(tv)))
336		return -EFAULT;
337	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
338		return -EDOM;
339
340	if (tv.tv_sec < 0) {
341		static int warned __read_mostly;
342
343		*timeo_p = 0;
344		if (warned < 10 && net_ratelimit()) {
345			warned++;
346			pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
347				__func__, current->comm, task_pid_nr(current));
348		}
349		return 0;
350	}
351	*timeo_p = MAX_SCHEDULE_TIMEOUT;
352	if (tv.tv_sec == 0 && tv.tv_usec == 0)
353		return 0;
354	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
355		*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
356	return 0;
357}
358
359static void sock_warn_obsolete_bsdism(const char *name)
360{
361	static int warned;
362	static char warncomm[TASK_COMM_LEN];
363	if (strcmp(warncomm, current->comm) && warned < 5) {
364		strcpy(warncomm,  current->comm);
365		pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
366			warncomm, name);
367		warned++;
368	}
369}
370
371#define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
372
373static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
374{
375	if (sk->sk_flags & flags) {
376		sk->sk_flags &= ~flags;
377		if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP))
378			net_disable_timestamp();
379	}
380}
381
382
383int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
384{
385	int err;
386	int skb_len;
387	unsigned long flags;
388	struct sk_buff_head *list = &sk->sk_receive_queue;
389
390	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
391		atomic_inc(&sk->sk_drops);
392		trace_sock_rcvqueue_full(sk, skb);
393		return -ENOMEM;
394	}
395
396	err = sk_filter(sk, skb);
397	if (err)
398		return err;
399
400	if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
401		atomic_inc(&sk->sk_drops);
402		return -ENOBUFS;
403	}
404
405	skb->dev = NULL;
406	skb_set_owner_r(skb, sk);
407
408	/* Cache the SKB length before we tack it onto the receive
409	 * queue.  Once it is added it no longer belongs to us and
410	 * may be freed by other threads of control pulling packets
411	 * from the queue.
412	 */
413	skb_len = skb->len;
414
415	/* we escape from rcu protected region, make sure we dont leak
416	 * a norefcounted dst
417	 */
418	skb_dst_force(skb);
419
420	spin_lock_irqsave(&list->lock, flags);
421	skb->dropcount = atomic_read(&sk->sk_drops);
422	__skb_queue_tail(list, skb);
423	spin_unlock_irqrestore(&list->lock, flags);
424
425	if (!sock_flag(sk, SOCK_DEAD))
426		sk->sk_data_ready(sk, skb_len);
427	return 0;
428}
429EXPORT_SYMBOL(sock_queue_rcv_skb);
430
431int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
432{
433	int rc = NET_RX_SUCCESS;
434
435	if (sk_filter(sk, skb))
436		goto discard_and_relse;
437
438	skb->dev = NULL;
439
440	if (sk_rcvqueues_full(sk, skb, sk->sk_rcvbuf)) {
441		atomic_inc(&sk->sk_drops);
442		goto discard_and_relse;
443	}
444	if (nested)
445		bh_lock_sock_nested(sk);
446	else
447		bh_lock_sock(sk);
448	if (!sock_owned_by_user(sk)) {
449		/*
450		 * trylock + unlock semantics:
451		 */
452		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
453
454		rc = sk_backlog_rcv(sk, skb);
455
456		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
457	} else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
458		bh_unlock_sock(sk);
459		atomic_inc(&sk->sk_drops);
460		goto discard_and_relse;
461	}
462
463	bh_unlock_sock(sk);
464out:
465	sock_put(sk);
466	return rc;
467discard_and_relse:
468	kfree_skb(skb);
469	goto out;
470}
471EXPORT_SYMBOL(sk_receive_skb);
472
473void sk_reset_txq(struct sock *sk)
474{
475	sk_tx_queue_clear(sk);
476}
477EXPORT_SYMBOL(sk_reset_txq);
478
479struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
480{
481	struct dst_entry *dst = __sk_dst_get(sk);
482
483	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
484		sk_tx_queue_clear(sk);
485		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
486		dst_release(dst);
487		return NULL;
488	}
489
490	return dst;
491}
492EXPORT_SYMBOL(__sk_dst_check);
493
494struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
495{
496	struct dst_entry *dst = sk_dst_get(sk);
497
498	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
499		sk_dst_reset(sk);
500		dst_release(dst);
501		return NULL;
502	}
503
504	return dst;
505}
506EXPORT_SYMBOL(sk_dst_check);
507
508static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
509{
510	int ret = -ENOPROTOOPT;
511#ifdef CONFIG_NETDEVICES
512	struct net *net = sock_net(sk);
513	char devname[IFNAMSIZ];
514	int index;
515
516	/* Sorry... */
517	ret = -EPERM;
518	if (!capable(CAP_NET_RAW))
519		goto out;
520
521	ret = -EINVAL;
522	if (optlen < 0)
523		goto out;
524
525	/* Bind this socket to a particular device like "eth0",
526	 * as specified in the passed interface name. If the
527	 * name is "" or the option length is zero the socket
528	 * is not bound.
529	 */
530	if (optlen > IFNAMSIZ - 1)
531		optlen = IFNAMSIZ - 1;
532	memset(devname, 0, sizeof(devname));
533
534	ret = -EFAULT;
535	if (copy_from_user(devname, optval, optlen))
536		goto out;
537
538	index = 0;
539	if (devname[0] != '\0') {
540		struct net_device *dev;
541
542		rcu_read_lock();
543		dev = dev_get_by_name_rcu(net, devname);
544		if (dev)
545			index = dev->ifindex;
546		rcu_read_unlock();
547		ret = -ENODEV;
548		if (!dev)
549			goto out;
550	}
551
552	lock_sock(sk);
553	sk->sk_bound_dev_if = index;
554	sk_dst_reset(sk);
555	release_sock(sk);
556
557	ret = 0;
558
559out:
560#endif
561
562	return ret;
563}
564
565static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
566{
567	if (valbool)
568		sock_set_flag(sk, bit);
569	else
570		sock_reset_flag(sk, bit);
571}
572
573/*
574 *	This is meant for all protocols to use and covers goings on
575 *	at the socket level. Everything here is generic.
576 */
577
578int sock_setsockopt(struct socket *sock, int level, int optname,
579		    char __user *optval, unsigned int optlen)
580{
581	struct sock *sk = sock->sk;
582	int val;
583	int valbool;
584	struct linger ling;
585	int ret = 0;
586
587	/*
588	 *	Options without arguments
589	 */
590
591	if (optname == SO_BINDTODEVICE)
592		return sock_bindtodevice(sk, optval, optlen);
593
594	if (optlen < sizeof(int))
595		return -EINVAL;
596
597	if (get_user(val, (int __user *)optval))
598		return -EFAULT;
599
600	valbool = val ? 1 : 0;
601
602	lock_sock(sk);
603
604	switch (optname) {
605	case SO_DEBUG:
606		if (val && !capable(CAP_NET_ADMIN))
607			ret = -EACCES;
608		else
609			sock_valbool_flag(sk, SOCK_DBG, valbool);
610		break;
611	case SO_REUSEADDR:
612		sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
613		break;
614	case SO_TYPE:
615	case SO_PROTOCOL:
616	case SO_DOMAIN:
617	case SO_ERROR:
618		ret = -ENOPROTOOPT;
619		break;
620	case SO_DONTROUTE:
621		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
622		break;
623	case SO_BROADCAST:
624		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
625		break;
626	case SO_SNDBUF:
627		/* Don't error on this BSD doesn't and if you think
628		 * about it this is right. Otherwise apps have to
629		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
630		 * are treated in BSD as hints
631		 */
632		val = min_t(u32, val, sysctl_wmem_max);
633set_sndbuf:
634		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
635		sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
636		/* Wake up sending tasks if we upped the value. */
637		sk->sk_write_space(sk);
638		break;
639
640	case SO_SNDBUFFORCE:
641		if (!capable(CAP_NET_ADMIN)) {
642			ret = -EPERM;
643			break;
644		}
645		goto set_sndbuf;
646
647	case SO_RCVBUF:
648		/* Don't error on this BSD doesn't and if you think
649		 * about it this is right. Otherwise apps have to
650		 * play 'guess the biggest size' games. RCVBUF/SNDBUF
651		 * are treated in BSD as hints
652		 */
653		val = min_t(u32, val, sysctl_rmem_max);
654set_rcvbuf:
655		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
656		/*
657		 * We double it on the way in to account for
658		 * "struct sk_buff" etc. overhead.   Applications
659		 * assume that the SO_RCVBUF setting they make will
660		 * allow that much actual data to be received on that
661		 * socket.
662		 *
663		 * Applications are unaware that "struct sk_buff" and
664		 * other overheads allocate from the receive buffer
665		 * during socket buffer allocation.
666		 *
667		 * And after considering the possible alternatives,
668		 * returning the value we actually used in getsockopt
669		 * is the most desirable behavior.
670		 */
671		sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
672		break;
673
674	case SO_RCVBUFFORCE:
675		if (!capable(CAP_NET_ADMIN)) {
676			ret = -EPERM;
677			break;
678		}
679		goto set_rcvbuf;
680
681	case SO_KEEPALIVE:
682#ifdef CONFIG_INET
683		if (sk->sk_protocol == IPPROTO_TCP)
684			tcp_set_keepalive(sk, valbool);
685#endif
686		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
687		break;
688
689	case SO_OOBINLINE:
690		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
691		break;
692
693	case SO_NO_CHECK:
694		sk->sk_no_check = valbool;
695		break;
696
697	case SO_PRIORITY:
698		if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
699			sk->sk_priority = val;
700		else
701			ret = -EPERM;
702		break;
703
704	case SO_LINGER:
705		if (optlen < sizeof(ling)) {
706			ret = -EINVAL;	/* 1003.1g */
707			break;
708		}
709		if (copy_from_user(&ling, optval, sizeof(ling))) {
710			ret = -EFAULT;
711			break;
712		}
713		if (!ling.l_onoff)
714			sock_reset_flag(sk, SOCK_LINGER);
715		else {
716#if (BITS_PER_LONG == 32)
717			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
718				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
719			else
720#endif
721				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
722			sock_set_flag(sk, SOCK_LINGER);
723		}
724		break;
725
726	case SO_BSDCOMPAT:
727		sock_warn_obsolete_bsdism("setsockopt");
728		break;
729
730	case SO_PASSCRED:
731		if (valbool)
732			set_bit(SOCK_PASSCRED, &sock->flags);
733		else
734			clear_bit(SOCK_PASSCRED, &sock->flags);
735		break;
736
737	case SO_TIMESTAMP:
738	case SO_TIMESTAMPNS:
739		if (valbool)  {
740			if (optname == SO_TIMESTAMP)
741				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
742			else
743				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
744			sock_set_flag(sk, SOCK_RCVTSTAMP);
745			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
746		} else {
747			sock_reset_flag(sk, SOCK_RCVTSTAMP);
748			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
749		}
750		break;
751
752	case SO_TIMESTAMPING:
753		if (val & ~SOF_TIMESTAMPING_MASK) {
754			ret = -EINVAL;
755			break;
756		}
757		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE,
758				  val & SOF_TIMESTAMPING_TX_HARDWARE);
759		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE,
760				  val & SOF_TIMESTAMPING_TX_SOFTWARE);
761		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE,
762				  val & SOF_TIMESTAMPING_RX_HARDWARE);
763		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
764			sock_enable_timestamp(sk,
765					      SOCK_TIMESTAMPING_RX_SOFTWARE);
766		else
767			sock_disable_timestamp(sk,
768					       (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
769		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE,
770				  val & SOF_TIMESTAMPING_SOFTWARE);
771		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE,
772				  val & SOF_TIMESTAMPING_SYS_HARDWARE);
773		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE,
774				  val & SOF_TIMESTAMPING_RAW_HARDWARE);
775		break;
776
777	case SO_RCVLOWAT:
778		if (val < 0)
779			val = INT_MAX;
780		sk->sk_rcvlowat = val ? : 1;
781		break;
782
783	case SO_RCVTIMEO:
784		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
785		break;
786
787	case SO_SNDTIMEO:
788		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
789		break;
790
791	case SO_ATTACH_FILTER:
792		ret = -EINVAL;
793		if (optlen == sizeof(struct sock_fprog)) {
794			struct sock_fprog fprog;
795
796			ret = -EFAULT;
797			if (copy_from_user(&fprog, optval, sizeof(fprog)))
798				break;
799
800			ret = sk_attach_filter(&fprog, sk);
801		}
802		break;
803
804	case SO_DETACH_FILTER:
805		ret = sk_detach_filter(sk);
806		break;
807
808	case SO_PASSSEC:
809		if (valbool)
810			set_bit(SOCK_PASSSEC, &sock->flags);
811		else
812			clear_bit(SOCK_PASSSEC, &sock->flags);
813		break;
814	case SO_MARK:
815		if (!capable(CAP_NET_ADMIN))
816			ret = -EPERM;
817		else
818			sk->sk_mark = val;
819		break;
820
821		/* We implement the SO_SNDLOWAT etc to
822		   not be settable (1003.1g 5.3) */
823	case SO_RXQ_OVFL:
824		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
825		break;
826
827	case SO_WIFI_STATUS:
828		sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
829		break;
830
831	case SO_PEEK_OFF:
832		if (sock->ops->set_peek_off)
833			sock->ops->set_peek_off(sk, val);
834		else
835			ret = -EOPNOTSUPP;
836		break;
837
838	case SO_NOFCS:
839		sock_valbool_flag(sk, SOCK_NOFCS, valbool);
840		break;
841
842	default:
843		ret = -ENOPROTOOPT;
844		break;
845	}
846	release_sock(sk);
847	return ret;
848}
849EXPORT_SYMBOL(sock_setsockopt);
850
851
852void cred_to_ucred(struct pid *pid, const struct cred *cred,
853		   struct ucred *ucred)
854{
855	ucred->pid = pid_vnr(pid);
856	ucred->uid = ucred->gid = -1;
857	if (cred) {
858		struct user_namespace *current_ns = current_user_ns();
859
860		ucred->uid = from_kuid(current_ns, cred->euid);
861		ucred->gid = from_kgid(current_ns, cred->egid);
862	}
863}
864EXPORT_SYMBOL_GPL(cred_to_ucred);
865
866int sock_getsockopt(struct socket *sock, int level, int optname,
867		    char __user *optval, int __user *optlen)
868{
869	struct sock *sk = sock->sk;
870
871	union {
872		int val;
873		struct linger ling;
874		struct timeval tm;
875	} v;
876
877	int lv = sizeof(int);
878	int len;
879
880	if (get_user(len, optlen))
881		return -EFAULT;
882	if (len < 0)
883		return -EINVAL;
884
885	memset(&v, 0, sizeof(v));
886
887	switch (optname) {
888	case SO_DEBUG:
889		v.val = sock_flag(sk, SOCK_DBG);
890		break;
891
892	case SO_DONTROUTE:
893		v.val = sock_flag(sk, SOCK_LOCALROUTE);
894		break;
895
896	case SO_BROADCAST:
897		v.val = sock_flag(sk, SOCK_BROADCAST);
898		break;
899
900	case SO_SNDBUF:
901		v.val = sk->sk_sndbuf;
902		break;
903
904	case SO_RCVBUF:
905		v.val = sk->sk_rcvbuf;
906		break;
907
908	case SO_REUSEADDR:
909		v.val = sk->sk_reuse;
910		break;
911
912	case SO_KEEPALIVE:
913		v.val = sock_flag(sk, SOCK_KEEPOPEN);
914		break;
915
916	case SO_TYPE:
917		v.val = sk->sk_type;
918		break;
919
920	case SO_PROTOCOL:
921		v.val = sk->sk_protocol;
922		break;
923
924	case SO_DOMAIN:
925		v.val = sk->sk_family;
926		break;
927
928	case SO_ERROR:
929		v.val = -sock_error(sk);
930		if (v.val == 0)
931			v.val = xchg(&sk->sk_err_soft, 0);
932		break;
933
934	case SO_OOBINLINE:
935		v.val = sock_flag(sk, SOCK_URGINLINE);
936		break;
937
938	case SO_NO_CHECK:
939		v.val = sk->sk_no_check;
940		break;
941
942	case SO_PRIORITY:
943		v.val = sk->sk_priority;
944		break;
945
946	case SO_LINGER:
947		lv		= sizeof(v.ling);
948		v.ling.l_onoff	= sock_flag(sk, SOCK_LINGER);
949		v.ling.l_linger	= sk->sk_lingertime / HZ;
950		break;
951
952	case SO_BSDCOMPAT:
953		sock_warn_obsolete_bsdism("getsockopt");
954		break;
955
956	case SO_TIMESTAMP:
957		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
958				!sock_flag(sk, SOCK_RCVTSTAMPNS);
959		break;
960
961	case SO_TIMESTAMPNS:
962		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
963		break;
964
965	case SO_TIMESTAMPING:
966		v.val = 0;
967		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
968			v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
969		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
970			v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
971		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
972			v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
973		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
974			v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
975		if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
976			v.val |= SOF_TIMESTAMPING_SOFTWARE;
977		if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
978			v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
979		if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
980			v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
981		break;
982
983	case SO_RCVTIMEO:
984		lv = sizeof(struct timeval);
985		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
986			v.tm.tv_sec = 0;
987			v.tm.tv_usec = 0;
988		} else {
989			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
990			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
991		}
992		break;
993
994	case SO_SNDTIMEO:
995		lv = sizeof(struct timeval);
996		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
997			v.tm.tv_sec = 0;
998			v.tm.tv_usec = 0;
999		} else {
1000			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1001			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1002		}
1003		break;
1004
1005	case SO_RCVLOWAT:
1006		v.val = sk->sk_rcvlowat;
1007		break;
1008
1009	case SO_SNDLOWAT:
1010		v.val = 1;
1011		break;
1012
1013	case SO_PASSCRED:
1014		v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1015		break;
1016
1017	case SO_PEERCRED:
1018	{
1019		struct ucred peercred;
1020		if (len > sizeof(peercred))
1021			len = sizeof(peercred);
1022		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1023		if (copy_to_user(optval, &peercred, len))
1024			return -EFAULT;
1025		goto lenout;
1026	}
1027
1028	case SO_PEERNAME:
1029	{
1030		char address[128];
1031
1032		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1033			return -ENOTCONN;
1034		if (lv < len)
1035			return -EINVAL;
1036		if (copy_to_user(optval, address, len))
1037			return -EFAULT;
1038		goto lenout;
1039	}
1040
1041	/* Dubious BSD thing... Probably nobody even uses it, but
1042	 * the UNIX standard wants it for whatever reason... -DaveM
1043	 */
1044	case SO_ACCEPTCONN:
1045		v.val = sk->sk_state == TCP_LISTEN;
1046		break;
1047
1048	case SO_PASSSEC:
1049		v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1050		break;
1051
1052	case SO_PEERSEC:
1053		return security_socket_getpeersec_stream(sock, optval, optlen, len);
1054
1055	case SO_MARK:
1056		v.val = sk->sk_mark;
1057		break;
1058
1059	case SO_RXQ_OVFL:
1060		v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1061		break;
1062
1063	case SO_WIFI_STATUS:
1064		v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1065		break;
1066
1067	case SO_PEEK_OFF:
1068		if (!sock->ops->set_peek_off)
1069			return -EOPNOTSUPP;
1070
1071		v.val = sk->sk_peek_off;
1072		break;
1073	case SO_NOFCS:
1074		v.val = sock_flag(sk, SOCK_NOFCS);
1075		break;
1076	default:
1077		return -ENOPROTOOPT;
1078	}
1079
1080	if (len > lv)
1081		len = lv;
1082	if (copy_to_user(optval, &v, len))
1083		return -EFAULT;
1084lenout:
1085	if (put_user(len, optlen))
1086		return -EFAULT;
1087	return 0;
1088}
1089
1090/*
1091 * Initialize an sk_lock.
1092 *
1093 * (We also register the sk_lock with the lock validator.)
1094 */
1095static inline void sock_lock_init(struct sock *sk)
1096{
1097	sock_lock_init_class_and_name(sk,
1098			af_family_slock_key_strings[sk->sk_family],
1099			af_family_slock_keys + sk->sk_family,
1100			af_family_key_strings[sk->sk_family],
1101			af_family_keys + sk->sk_family);
1102}
1103
1104/*
1105 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1106 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1107 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1108 */
1109static void sock_copy(struct sock *nsk, const struct sock *osk)
1110{
1111#ifdef CONFIG_SECURITY_NETWORK
1112	void *sptr = nsk->sk_security;
1113#endif
1114	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1115
1116	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1117	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1118
1119#ifdef CONFIG_SECURITY_NETWORK
1120	nsk->sk_security = sptr;
1121	security_sk_clone(osk, nsk);
1122#endif
1123}
1124
1125/*
1126 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
1127 * un-modified. Special care is taken when initializing object to zero.
1128 */
1129static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1130{
1131	if (offsetof(struct sock, sk_node.next) != 0)
1132		memset(sk, 0, offsetof(struct sock, sk_node.next));
1133	memset(&sk->sk_node.pprev, 0,
1134	       size - offsetof(struct sock, sk_node.pprev));
1135}
1136
1137void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1138{
1139	unsigned long nulls1, nulls2;
1140
1141	nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1142	nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1143	if (nulls1 > nulls2)
1144		swap(nulls1, nulls2);
1145
1146	if (nulls1 != 0)
1147		memset((char *)sk, 0, nulls1);
1148	memset((char *)sk + nulls1 + sizeof(void *), 0,
1149	       nulls2 - nulls1 - sizeof(void *));
1150	memset((char *)sk + nulls2 + sizeof(void *), 0,
1151	       size - nulls2 - sizeof(void *));
1152}
1153EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1154
1155static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1156		int family)
1157{
1158	struct sock *sk;
1159	struct kmem_cache *slab;
1160
1161	slab = prot->slab;
1162	if (slab != NULL) {
1163		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1164		if (!sk)
1165			return sk;
1166		if (priority & __GFP_ZERO) {
1167			if (prot->clear_sk)
1168				prot->clear_sk(sk, prot->obj_size);
1169			else
1170				sk_prot_clear_nulls(sk, prot->obj_size);
1171		}
1172	} else
1173		sk = kmalloc(prot->obj_size, priority);
1174
1175	if (sk != NULL) {
1176		kmemcheck_annotate_bitfield(sk, flags);
1177
1178		if (security_sk_alloc(sk, family, priority))
1179			goto out_free;
1180
1181		if (!try_module_get(prot->owner))
1182			goto out_free_sec;
1183		sk_tx_queue_clear(sk);
1184	}
1185
1186	return sk;
1187
1188out_free_sec:
1189	security_sk_free(sk);
1190out_free:
1191	if (slab != NULL)
1192		kmem_cache_free(slab, sk);
1193	else
1194		kfree(sk);
1195	return NULL;
1196}
1197
1198static void sk_prot_free(struct proto *prot, struct sock *sk)
1199{
1200	struct kmem_cache *slab;
1201	struct module *owner;
1202
1203	owner = prot->owner;
1204	slab = prot->slab;
1205
1206	security_sk_free(sk);
1207	if (slab != NULL)
1208		kmem_cache_free(slab, sk);
1209	else
1210		kfree(sk);
1211	module_put(owner);
1212}
1213
1214#ifdef CONFIG_CGROUPS
1215#if IS_ENABLED(CONFIG_NET_CLS_CGROUP)
1216void sock_update_classid(struct sock *sk)
1217{
1218	u32 classid;
1219
1220	rcu_read_lock();  /* doing current task, which cannot vanish. */
1221	classid = task_cls_classid(current);
1222	rcu_read_unlock();
1223	if (classid && classid != sk->sk_classid)
1224		sk->sk_classid = classid;
1225}
1226EXPORT_SYMBOL(sock_update_classid);
1227#endif
1228
1229#if IS_ENABLED(CONFIG_NETPRIO_CGROUP)
1230void sock_update_netprioidx(struct sock *sk, struct task_struct *task)
1231{
1232	if (in_interrupt())
1233		return;
1234
1235	sk->sk_cgrp_prioidx = task_netprioidx(task);
1236}
1237EXPORT_SYMBOL_GPL(sock_update_netprioidx);
1238#endif
1239#endif
1240
1241/**
1242 *	sk_alloc - All socket objects are allocated here
1243 *	@net: the applicable net namespace
1244 *	@family: protocol family
1245 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1246 *	@prot: struct proto associated with this new sock instance
1247 */
1248struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1249		      struct proto *prot)
1250{
1251	struct sock *sk;
1252
1253	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1254	if (sk) {
1255		sk->sk_family = family;
1256		/*
1257		 * See comment in struct sock definition to understand
1258		 * why we need sk_prot_creator -acme
1259		 */
1260		sk->sk_prot = sk->sk_prot_creator = prot;
1261		sock_lock_init(sk);
1262		sock_net_set(sk, get_net(net));
1263		atomic_set(&sk->sk_wmem_alloc, 1);
1264
1265		sock_update_classid(sk);
1266		sock_update_netprioidx(sk, current);
1267	}
1268
1269	return sk;
1270}
1271EXPORT_SYMBOL(sk_alloc);
1272
1273static void __sk_free(struct sock *sk)
1274{
1275	struct sk_filter *filter;
1276
1277	if (sk->sk_destruct)
1278		sk->sk_destruct(sk);
1279
1280	filter = rcu_dereference_check(sk->sk_filter,
1281				       atomic_read(&sk->sk_wmem_alloc) == 0);
1282	if (filter) {
1283		sk_filter_uncharge(sk, filter);
1284		RCU_INIT_POINTER(sk->sk_filter, NULL);
1285	}
1286
1287	sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1288
1289	if (atomic_read(&sk->sk_omem_alloc))
1290		pr_debug("%s: optmem leakage (%d bytes) detected\n",
1291			 __func__, atomic_read(&sk->sk_omem_alloc));
1292
1293	if (sk->sk_peer_cred)
1294		put_cred(sk->sk_peer_cred);
1295	put_pid(sk->sk_peer_pid);
1296	put_net(sock_net(sk));
1297	sk_prot_free(sk->sk_prot_creator, sk);
1298}
1299
1300void sk_free(struct sock *sk)
1301{
1302	/*
1303	 * We subtract one from sk_wmem_alloc and can know if
1304	 * some packets are still in some tx queue.
1305	 * If not null, sock_wfree() will call __sk_free(sk) later
1306	 */
1307	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1308		__sk_free(sk);
1309}
1310EXPORT_SYMBOL(sk_free);
1311
1312/*
1313 * Last sock_put should drop reference to sk->sk_net. It has already
1314 * been dropped in sk_change_net. Taking reference to stopping namespace
1315 * is not an option.
1316 * Take reference to a socket to remove it from hash _alive_ and after that
1317 * destroy it in the context of init_net.
1318 */
1319void sk_release_kernel(struct sock *sk)
1320{
1321	if (sk == NULL || sk->sk_socket == NULL)
1322		return;
1323
1324	sock_hold(sk);
1325	sock_release(sk->sk_socket);
1326	release_net(sock_net(sk));
1327	sock_net_set(sk, get_net(&init_net));
1328	sock_put(sk);
1329}
1330EXPORT_SYMBOL(sk_release_kernel);
1331
1332static void sk_update_clone(const struct sock *sk, struct sock *newsk)
1333{
1334	if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1335		sock_update_memcg(newsk);
1336}
1337
1338/**
1339 *	sk_clone_lock - clone a socket, and lock its clone
1340 *	@sk: the socket to clone
1341 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1342 *
1343 *	Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1344 */
1345struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1346{
1347	struct sock *newsk;
1348
1349	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1350	if (newsk != NULL) {
1351		struct sk_filter *filter;
1352
1353		sock_copy(newsk, sk);
1354
1355		/* SANITY */
1356		get_net(sock_net(newsk));
1357		sk_node_init(&newsk->sk_node);
1358		sock_lock_init(newsk);
1359		bh_lock_sock(newsk);
1360		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1361		newsk->sk_backlog.len = 0;
1362
1363		atomic_set(&newsk->sk_rmem_alloc, 0);
1364		/*
1365		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1366		 */
1367		atomic_set(&newsk->sk_wmem_alloc, 1);
1368		atomic_set(&newsk->sk_omem_alloc, 0);
1369		skb_queue_head_init(&newsk->sk_receive_queue);
1370		skb_queue_head_init(&newsk->sk_write_queue);
1371#ifdef CONFIG_NET_DMA
1372		skb_queue_head_init(&newsk->sk_async_wait_queue);
1373#endif
1374
1375		spin_lock_init(&newsk->sk_dst_lock);
1376		rwlock_init(&newsk->sk_callback_lock);
1377		lockdep_set_class_and_name(&newsk->sk_callback_lock,
1378				af_callback_keys + newsk->sk_family,
1379				af_family_clock_key_strings[newsk->sk_family]);
1380
1381		newsk->sk_dst_cache	= NULL;
1382		newsk->sk_wmem_queued	= 0;
1383		newsk->sk_forward_alloc = 0;
1384		newsk->sk_send_head	= NULL;
1385		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1386
1387		sock_reset_flag(newsk, SOCK_DONE);
1388		skb_queue_head_init(&newsk->sk_error_queue);
1389
1390		filter = rcu_dereference_protected(newsk->sk_filter, 1);
1391		if (filter != NULL)
1392			sk_filter_charge(newsk, filter);
1393
1394		if (unlikely(xfrm_sk_clone_policy(newsk))) {
1395			/* It is still raw copy of parent, so invalidate
1396			 * destructor and make plain sk_free() */
1397			newsk->sk_destruct = NULL;
1398			bh_unlock_sock(newsk);
1399			sk_free(newsk);
1400			newsk = NULL;
1401			goto out;
1402		}
1403
1404		newsk->sk_err	   = 0;
1405		newsk->sk_priority = 0;
1406		/*
1407		 * Before updating sk_refcnt, we must commit prior changes to memory
1408		 * (Documentation/RCU/rculist_nulls.txt for details)
1409		 */
1410		smp_wmb();
1411		atomic_set(&newsk->sk_refcnt, 2);
1412
1413		/*
1414		 * Increment the counter in the same struct proto as the master
1415		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1416		 * is the same as sk->sk_prot->socks, as this field was copied
1417		 * with memcpy).
1418		 *
1419		 * This _changes_ the previous behaviour, where
1420		 * tcp_create_openreq_child always was incrementing the
1421		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1422		 * to be taken into account in all callers. -acme
1423		 */
1424		sk_refcnt_debug_inc(newsk);
1425		sk_set_socket(newsk, NULL);
1426		newsk->sk_wq = NULL;
1427
1428		sk_update_clone(sk, newsk);
1429
1430		if (newsk->sk_prot->sockets_allocated)
1431			sk_sockets_allocated_inc(newsk);
1432
1433		if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1434			net_enable_timestamp();
1435	}
1436out:
1437	return newsk;
1438}
1439EXPORT_SYMBOL_GPL(sk_clone_lock);
1440
1441void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1442{
1443	__sk_dst_set(sk, dst);
1444	sk->sk_route_caps = dst->dev->features;
1445	if (sk->sk_route_caps & NETIF_F_GSO)
1446		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1447	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1448	if (sk_can_gso(sk)) {
1449		if (dst->header_len) {
1450			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1451		} else {
1452			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1453			sk->sk_gso_max_size = dst->dev->gso_max_size;
1454			sk->sk_gso_max_segs = dst->dev->gso_max_segs;
1455		}
1456	}
1457}
1458EXPORT_SYMBOL_GPL(sk_setup_caps);
1459
1460void __init sk_init(void)
1461{
1462	if (totalram_pages <= 4096) {
1463		sysctl_wmem_max = 32767;
1464		sysctl_rmem_max = 32767;
1465		sysctl_wmem_default = 32767;
1466		sysctl_rmem_default = 32767;
1467	} else if (totalram_pages >= 131072) {
1468		sysctl_wmem_max = 131071;
1469		sysctl_rmem_max = 131071;
1470	}
1471}
1472
1473/*
1474 *	Simple resource managers for sockets.
1475 */
1476
1477
1478/*
1479 * Write buffer destructor automatically called from kfree_skb.
1480 */
1481void sock_wfree(struct sk_buff *skb)
1482{
1483	struct sock *sk = skb->sk;
1484	unsigned int len = skb->truesize;
1485
1486	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1487		/*
1488		 * Keep a reference on sk_wmem_alloc, this will be released
1489		 * after sk_write_space() call
1490		 */
1491		atomic_sub(len - 1, &sk->sk_wmem_alloc);
1492		sk->sk_write_space(sk);
1493		len = 1;
1494	}
1495	/*
1496	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1497	 * could not do because of in-flight packets
1498	 */
1499	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1500		__sk_free(sk);
1501}
1502EXPORT_SYMBOL(sock_wfree);
1503
1504/*
1505 * Read buffer destructor automatically called from kfree_skb.
1506 */
1507void sock_rfree(struct sk_buff *skb)
1508{
1509	struct sock *sk = skb->sk;
1510	unsigned int len = skb->truesize;
1511
1512	atomic_sub(len, &sk->sk_rmem_alloc);
1513	sk_mem_uncharge(sk, len);
1514}
1515EXPORT_SYMBOL(sock_rfree);
1516
1517void sock_edemux(struct sk_buff *skb)
1518{
1519	sock_put(skb->sk);
1520}
1521EXPORT_SYMBOL(sock_edemux);
1522
1523int sock_i_uid(struct sock *sk)
1524{
1525	int uid;
1526
1527	read_lock_bh(&sk->sk_callback_lock);
1528	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1529	read_unlock_bh(&sk->sk_callback_lock);
1530	return uid;
1531}
1532EXPORT_SYMBOL(sock_i_uid);
1533
1534unsigned long sock_i_ino(struct sock *sk)
1535{
1536	unsigned long ino;
1537
1538	read_lock_bh(&sk->sk_callback_lock);
1539	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1540	read_unlock_bh(&sk->sk_callback_lock);
1541	return ino;
1542}
1543EXPORT_SYMBOL(sock_i_ino);
1544
1545/*
1546 * Allocate a skb from the socket's send buffer.
1547 */
1548struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1549			     gfp_t priority)
1550{
1551	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1552		struct sk_buff *skb = alloc_skb(size, priority);
1553		if (skb) {
1554			skb_set_owner_w(skb, sk);
1555			return skb;
1556		}
1557	}
1558	return NULL;
1559}
1560EXPORT_SYMBOL(sock_wmalloc);
1561
1562/*
1563 * Allocate a skb from the socket's receive buffer.
1564 */
1565struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1566			     gfp_t priority)
1567{
1568	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1569		struct sk_buff *skb = alloc_skb(size, priority);
1570		if (skb) {
1571			skb_set_owner_r(skb, sk);
1572			return skb;
1573		}
1574	}
1575	return NULL;
1576}
1577
1578/*
1579 * Allocate a memory block from the socket's option memory buffer.
1580 */
1581void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1582{
1583	if ((unsigned int)size <= sysctl_optmem_max &&
1584	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1585		void *mem;
1586		/* First do the add, to avoid the race if kmalloc
1587		 * might sleep.
1588		 */
1589		atomic_add(size, &sk->sk_omem_alloc);
1590		mem = kmalloc(size, priority);
1591		if (mem)
1592			return mem;
1593		atomic_sub(size, &sk->sk_omem_alloc);
1594	}
1595	return NULL;
1596}
1597EXPORT_SYMBOL(sock_kmalloc);
1598
1599/*
1600 * Free an option memory block.
1601 */
1602void sock_kfree_s(struct sock *sk, void *mem, int size)
1603{
1604	kfree(mem);
1605	atomic_sub(size, &sk->sk_omem_alloc);
1606}
1607EXPORT_SYMBOL(sock_kfree_s);
1608
1609/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1610   I think, these locks should be removed for datagram sockets.
1611 */
1612static long sock_wait_for_wmem(struct sock *sk, long timeo)
1613{
1614	DEFINE_WAIT(wait);
1615
1616	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1617	for (;;) {
1618		if (!timeo)
1619			break;
1620		if (signal_pending(current))
1621			break;
1622		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1623		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1624		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1625			break;
1626		if (sk->sk_shutdown & SEND_SHUTDOWN)
1627			break;
1628		if (sk->sk_err)
1629			break;
1630		timeo = schedule_timeout(timeo);
1631	}
1632	finish_wait(sk_sleep(sk), &wait);
1633	return timeo;
1634}
1635
1636
1637/*
1638 *	Generic send/receive buffer handlers
1639 */
1640
1641struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1642				     unsigned long data_len, int noblock,
1643				     int *errcode)
1644{
1645	struct sk_buff *skb;
1646	gfp_t gfp_mask;
1647	long timeo;
1648	int err;
1649	int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1650
1651	err = -EMSGSIZE;
1652	if (npages > MAX_SKB_FRAGS)
1653		goto failure;
1654
1655	gfp_mask = sk->sk_allocation;
1656	if (gfp_mask & __GFP_WAIT)
1657		gfp_mask |= __GFP_REPEAT;
1658
1659	timeo = sock_sndtimeo(sk, noblock);
1660	while (1) {
1661		err = sock_error(sk);
1662		if (err != 0)
1663			goto failure;
1664
1665		err = -EPIPE;
1666		if (sk->sk_shutdown & SEND_SHUTDOWN)
1667			goto failure;
1668
1669		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1670			skb = alloc_skb(header_len, gfp_mask);
1671			if (skb) {
1672				int i;
1673
1674				/* No pages, we're done... */
1675				if (!data_len)
1676					break;
1677
1678				skb->truesize += data_len;
1679				skb_shinfo(skb)->nr_frags = npages;
1680				for (i = 0; i < npages; i++) {
1681					struct page *page;
1682
1683					page = alloc_pages(sk->sk_allocation, 0);
1684					if (!page) {
1685						err = -ENOBUFS;
1686						skb_shinfo(skb)->nr_frags = i;
1687						kfree_skb(skb);
1688						goto failure;
1689					}
1690
1691					__skb_fill_page_desc(skb, i,
1692							page, 0,
1693							(data_len >= PAGE_SIZE ?
1694							 PAGE_SIZE :
1695							 data_len));
1696					data_len -= PAGE_SIZE;
1697				}
1698
1699				/* Full success... */
1700				break;
1701			}
1702			err = -ENOBUFS;
1703			goto failure;
1704		}
1705		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1706		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1707		err = -EAGAIN;
1708		if (!timeo)
1709			goto failure;
1710		if (signal_pending(current))
1711			goto interrupted;
1712		timeo = sock_wait_for_wmem(sk, timeo);
1713	}
1714
1715	skb_set_owner_w(skb, sk);
1716	return skb;
1717
1718interrupted:
1719	err = sock_intr_errno(timeo);
1720failure:
1721	*errcode = err;
1722	return NULL;
1723}
1724EXPORT_SYMBOL(sock_alloc_send_pskb);
1725
1726struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1727				    int noblock, int *errcode)
1728{
1729	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1730}
1731EXPORT_SYMBOL(sock_alloc_send_skb);
1732
1733static void __lock_sock(struct sock *sk)
1734	__releases(&sk->sk_lock.slock)
1735	__acquires(&sk->sk_lock.slock)
1736{
1737	DEFINE_WAIT(wait);
1738
1739	for (;;) {
1740		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1741					TASK_UNINTERRUPTIBLE);
1742		spin_unlock_bh(&sk->sk_lock.slock);
1743		schedule();
1744		spin_lock_bh(&sk->sk_lock.slock);
1745		if (!sock_owned_by_user(sk))
1746			break;
1747	}
1748	finish_wait(&sk->sk_lock.wq, &wait);
1749}
1750
1751static void __release_sock(struct sock *sk)
1752	__releases(&sk->sk_lock.slock)
1753	__acquires(&sk->sk_lock.slock)
1754{
1755	struct sk_buff *skb = sk->sk_backlog.head;
1756
1757	do {
1758		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1759		bh_unlock_sock(sk);
1760
1761		do {
1762			struct sk_buff *next = skb->next;
1763
1764			prefetch(next);
1765			WARN_ON_ONCE(skb_dst_is_noref(skb));
1766			skb->next = NULL;
1767			sk_backlog_rcv(sk, skb);
1768
1769			/*
1770			 * We are in process context here with softirqs
1771			 * disabled, use cond_resched_softirq() to preempt.
1772			 * This is safe to do because we've taken the backlog
1773			 * queue private:
1774			 */
1775			cond_resched_softirq();
1776
1777			skb = next;
1778		} while (skb != NULL);
1779
1780		bh_lock_sock(sk);
1781	} while ((skb = sk->sk_backlog.head) != NULL);
1782
1783	/*
1784	 * Doing the zeroing here guarantee we can not loop forever
1785	 * while a wild producer attempts to flood us.
1786	 */
1787	sk->sk_backlog.len = 0;
1788}
1789
1790/**
1791 * sk_wait_data - wait for data to arrive at sk_receive_queue
1792 * @sk:    sock to wait on
1793 * @timeo: for how long
1794 *
1795 * Now socket state including sk->sk_err is changed only under lock,
1796 * hence we may omit checks after joining wait queue.
1797 * We check receive queue before schedule() only as optimization;
1798 * it is very likely that release_sock() added new data.
1799 */
1800int sk_wait_data(struct sock *sk, long *timeo)
1801{
1802	int rc;
1803	DEFINE_WAIT(wait);
1804
1805	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1806	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1807	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1808	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1809	finish_wait(sk_sleep(sk), &wait);
1810	return rc;
1811}
1812EXPORT_SYMBOL(sk_wait_data);
1813
1814/**
1815 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1816 *	@sk: socket
1817 *	@size: memory size to allocate
1818 *	@kind: allocation type
1819 *
1820 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1821 *	rmem allocation. This function assumes that protocols which have
1822 *	memory_pressure use sk_wmem_queued as write buffer accounting.
1823 */
1824int __sk_mem_schedule(struct sock *sk, int size, int kind)
1825{
1826	struct proto *prot = sk->sk_prot;
1827	int amt = sk_mem_pages(size);
1828	long allocated;
1829	int parent_status = UNDER_LIMIT;
1830
1831	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1832
1833	allocated = sk_memory_allocated_add(sk, amt, &parent_status);
1834
1835	/* Under limit. */
1836	if (parent_status == UNDER_LIMIT &&
1837			allocated <= sk_prot_mem_limits(sk, 0)) {
1838		sk_leave_memory_pressure(sk);
1839		return 1;
1840	}
1841
1842	/* Under pressure. (we or our parents) */
1843	if ((parent_status > SOFT_LIMIT) ||
1844			allocated > sk_prot_mem_limits(sk, 1))
1845		sk_enter_memory_pressure(sk);
1846
1847	/* Over hard limit (we or our parents) */
1848	if ((parent_status == OVER_LIMIT) ||
1849			(allocated > sk_prot_mem_limits(sk, 2)))
1850		goto suppress_allocation;
1851
1852	/* guarantee minimum buffer size under pressure */
1853	if (kind == SK_MEM_RECV) {
1854		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1855			return 1;
1856
1857	} else { /* SK_MEM_SEND */
1858		if (sk->sk_type == SOCK_STREAM) {
1859			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1860				return 1;
1861		} else if (atomic_read(&sk->sk_wmem_alloc) <
1862			   prot->sysctl_wmem[0])
1863				return 1;
1864	}
1865
1866	if (sk_has_memory_pressure(sk)) {
1867		int alloc;
1868
1869		if (!sk_under_memory_pressure(sk))
1870			return 1;
1871		alloc = sk_sockets_allocated_read_positive(sk);
1872		if (sk_prot_mem_limits(sk, 2) > alloc *
1873		    sk_mem_pages(sk->sk_wmem_queued +
1874				 atomic_read(&sk->sk_rmem_alloc) +
1875				 sk->sk_forward_alloc))
1876			return 1;
1877	}
1878
1879suppress_allocation:
1880
1881	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1882		sk_stream_moderate_sndbuf(sk);
1883
1884		/* Fail only if socket is _under_ its sndbuf.
1885		 * In this case we cannot block, so that we have to fail.
1886		 */
1887		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1888			return 1;
1889	}
1890
1891	trace_sock_exceed_buf_limit(sk, prot, allocated);
1892
1893	/* Alas. Undo changes. */
1894	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1895
1896	sk_memory_allocated_sub(sk, amt);
1897
1898	return 0;
1899}
1900EXPORT_SYMBOL(__sk_mem_schedule);
1901
1902/**
1903 *	__sk_reclaim - reclaim memory_allocated
1904 *	@sk: socket
1905 */
1906void __sk_mem_reclaim(struct sock *sk)
1907{
1908	sk_memory_allocated_sub(sk,
1909				sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT);
1910	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1911
1912	if (sk_under_memory_pressure(sk) &&
1913	    (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
1914		sk_leave_memory_pressure(sk);
1915}
1916EXPORT_SYMBOL(__sk_mem_reclaim);
1917
1918
1919/*
1920 * Set of default routines for initialising struct proto_ops when
1921 * the protocol does not support a particular function. In certain
1922 * cases where it makes no sense for a protocol to have a "do nothing"
1923 * function, some default processing is provided.
1924 */
1925
1926int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1927{
1928	return -EOPNOTSUPP;
1929}
1930EXPORT_SYMBOL(sock_no_bind);
1931
1932int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1933		    int len, int flags)
1934{
1935	return -EOPNOTSUPP;
1936}
1937EXPORT_SYMBOL(sock_no_connect);
1938
1939int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1940{
1941	return -EOPNOTSUPP;
1942}
1943EXPORT_SYMBOL(sock_no_socketpair);
1944
1945int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1946{
1947	return -EOPNOTSUPP;
1948}
1949EXPORT_SYMBOL(sock_no_accept);
1950
1951int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1952		    int *len, int peer)
1953{
1954	return -EOPNOTSUPP;
1955}
1956EXPORT_SYMBOL(sock_no_getname);
1957
1958unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1959{
1960	return 0;
1961}
1962EXPORT_SYMBOL(sock_no_poll);
1963
1964int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1965{
1966	return -EOPNOTSUPP;
1967}
1968EXPORT_SYMBOL(sock_no_ioctl);
1969
1970int sock_no_listen(struct socket *sock, int backlog)
1971{
1972	return -EOPNOTSUPP;
1973}
1974EXPORT_SYMBOL(sock_no_listen);
1975
1976int sock_no_shutdown(struct socket *sock, int how)
1977{
1978	return -EOPNOTSUPP;
1979}
1980EXPORT_SYMBOL(sock_no_shutdown);
1981
1982int sock_no_setsockopt(struct socket *sock, int level, int optname,
1983		    char __user *optval, unsigned int optlen)
1984{
1985	return -EOPNOTSUPP;
1986}
1987EXPORT_SYMBOL(sock_no_setsockopt);
1988
1989int sock_no_getsockopt(struct socket *sock, int level, int optname,
1990		    char __user *optval, int __user *optlen)
1991{
1992	return -EOPNOTSUPP;
1993}
1994EXPORT_SYMBOL(sock_no_getsockopt);
1995
1996int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1997		    size_t len)
1998{
1999	return -EOPNOTSUPP;
2000}
2001EXPORT_SYMBOL(sock_no_sendmsg);
2002
2003int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2004		    size_t len, int flags)
2005{
2006	return -EOPNOTSUPP;
2007}
2008EXPORT_SYMBOL(sock_no_recvmsg);
2009
2010int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2011{
2012	/* Mirror missing mmap method error code */
2013	return -ENODEV;
2014}
2015EXPORT_SYMBOL(sock_no_mmap);
2016
2017ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2018{
2019	ssize_t res;
2020	struct msghdr msg = {.msg_flags = flags};
2021	struct kvec iov;
2022	char *kaddr = kmap(page);
2023	iov.iov_base = kaddr + offset;
2024	iov.iov_len = size;
2025	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2026	kunmap(page);
2027	return res;
2028}
2029EXPORT_SYMBOL(sock_no_sendpage);
2030
2031/*
2032 *	Default Socket Callbacks
2033 */
2034
2035static void sock_def_wakeup(struct sock *sk)
2036{
2037	struct socket_wq *wq;
2038
2039	rcu_read_lock();
2040	wq = rcu_dereference(sk->sk_wq);
2041	if (wq_has_sleeper(wq))
2042		wake_up_interruptible_all(&wq->wait);
2043	rcu_read_unlock();
2044}
2045
2046static void sock_def_error_report(struct sock *sk)
2047{
2048	struct socket_wq *wq;
2049
2050	rcu_read_lock();
2051	wq = rcu_dereference(sk->sk_wq);
2052	if (wq_has_sleeper(wq))
2053		wake_up_interruptible_poll(&wq->wait, POLLERR);
2054	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2055	rcu_read_unlock();
2056}
2057
2058static void sock_def_readable(struct sock *sk, int len)
2059{
2060	struct socket_wq *wq;
2061
2062	rcu_read_lock();
2063	wq = rcu_dereference(sk->sk_wq);
2064	if (wq_has_sleeper(wq))
2065		wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2066						POLLRDNORM | POLLRDBAND);
2067	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2068	rcu_read_unlock();
2069}
2070
2071static void sock_def_write_space(struct sock *sk)
2072{
2073	struct socket_wq *wq;
2074
2075	rcu_read_lock();
2076
2077	/* Do not wake up a writer until he can make "significant"
2078	 * progress.  --DaveM
2079	 */
2080	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2081		wq = rcu_dereference(sk->sk_wq);
2082		if (wq_has_sleeper(wq))
2083			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2084						POLLWRNORM | POLLWRBAND);
2085
2086		/* Should agree with poll, otherwise some programs break */
2087		if (sock_writeable(sk))
2088			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2089	}
2090
2091	rcu_read_unlock();
2092}
2093
2094static void sock_def_destruct(struct sock *sk)
2095{
2096	kfree(sk->sk_protinfo);
2097}
2098
2099void sk_send_sigurg(struct sock *sk)
2100{
2101	if (sk->sk_socket && sk->sk_socket->file)
2102		if (send_sigurg(&sk->sk_socket->file->f_owner))
2103			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2104}
2105EXPORT_SYMBOL(sk_send_sigurg);
2106
2107void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2108		    unsigned long expires)
2109{
2110	if (!mod_timer(timer, expires))
2111		sock_hold(sk);
2112}
2113EXPORT_SYMBOL(sk_reset_timer);
2114
2115void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2116{
2117	if (timer_pending(timer) && del_timer(timer))
2118		__sock_put(sk);
2119}
2120EXPORT_SYMBOL(sk_stop_timer);
2121
2122void sock_init_data(struct socket *sock, struct sock *sk)
2123{
2124	skb_queue_head_init(&sk->sk_receive_queue);
2125	skb_queue_head_init(&sk->sk_write_queue);
2126	skb_queue_head_init(&sk->sk_error_queue);
2127#ifdef CONFIG_NET_DMA
2128	skb_queue_head_init(&sk->sk_async_wait_queue);
2129#endif
2130
2131	sk->sk_send_head	=	NULL;
2132
2133	init_timer(&sk->sk_timer);
2134
2135	sk->sk_allocation	=	GFP_KERNEL;
2136	sk->sk_rcvbuf		=	sysctl_rmem_default;
2137	sk->sk_sndbuf		=	sysctl_wmem_default;
2138	sk->sk_state		=	TCP_CLOSE;
2139	sk_set_socket(sk, sock);
2140
2141	sock_set_flag(sk, SOCK_ZAPPED);
2142
2143	if (sock) {
2144		sk->sk_type	=	sock->type;
2145		sk->sk_wq	=	sock->wq;
2146		sock->sk	=	sk;
2147	} else
2148		sk->sk_wq	=	NULL;
2149
2150	spin_lock_init(&sk->sk_dst_lock);
2151	rwlock_init(&sk->sk_callback_lock);
2152	lockdep_set_class_and_name(&sk->sk_callback_lock,
2153			af_callback_keys + sk->sk_family,
2154			af_family_clock_key_strings[sk->sk_family]);
2155
2156	sk->sk_state_change	=	sock_def_wakeup;
2157	sk->sk_data_ready	=	sock_def_readable;
2158	sk->sk_write_space	=	sock_def_write_space;
2159	sk->sk_error_report	=	sock_def_error_report;
2160	sk->sk_destruct		=	sock_def_destruct;
2161
2162	sk->sk_sndmsg_page	=	NULL;
2163	sk->sk_sndmsg_off	=	0;
2164	sk->sk_peek_off		=	-1;
2165
2166	sk->sk_peer_pid 	=	NULL;
2167	sk->sk_peer_cred	=	NULL;
2168	sk->sk_write_pending	=	0;
2169	sk->sk_rcvlowat		=	1;
2170	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2171	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2172
2173	sk->sk_stamp = ktime_set(-1L, 0);
2174
2175	/*
2176	 * Before updating sk_refcnt, we must commit prior changes to memory
2177	 * (Documentation/RCU/rculist_nulls.txt for details)
2178	 */
2179	smp_wmb();
2180	atomic_set(&sk->sk_refcnt, 1);
2181	atomic_set(&sk->sk_drops, 0);
2182}
2183EXPORT_SYMBOL(sock_init_data);
2184
2185void lock_sock_nested(struct sock *sk, int subclass)
2186{
2187	might_sleep();
2188	spin_lock_bh(&sk->sk_lock.slock);
2189	if (sk->sk_lock.owned)
2190		__lock_sock(sk);
2191	sk->sk_lock.owned = 1;
2192	spin_unlock(&sk->sk_lock.slock);
2193	/*
2194	 * The sk_lock has mutex_lock() semantics here:
2195	 */
2196	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2197	local_bh_enable();
2198}
2199EXPORT_SYMBOL(lock_sock_nested);
2200
2201void release_sock(struct sock *sk)
2202{
2203	/*
2204	 * The sk_lock has mutex_unlock() semantics:
2205	 */
2206	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2207
2208	spin_lock_bh(&sk->sk_lock.slock);
2209	if (sk->sk_backlog.tail)
2210		__release_sock(sk);
2211
2212	if (sk->sk_prot->release_cb)
2213		sk->sk_prot->release_cb(sk);
2214
2215	sk->sk_lock.owned = 0;
2216	if (waitqueue_active(&sk->sk_lock.wq))
2217		wake_up(&sk->sk_lock.wq);
2218	spin_unlock_bh(&sk->sk_lock.slock);
2219}
2220EXPORT_SYMBOL(release_sock);
2221
2222/**
2223 * lock_sock_fast - fast version of lock_sock
2224 * @sk: socket
2225 *
2226 * This version should be used for very small section, where process wont block
2227 * return false if fast path is taken
2228 *   sk_lock.slock locked, owned = 0, BH disabled
2229 * return true if slow path is taken
2230 *   sk_lock.slock unlocked, owned = 1, BH enabled
2231 */
2232bool lock_sock_fast(struct sock *sk)
2233{
2234	might_sleep();
2235	spin_lock_bh(&sk->sk_lock.slock);
2236
2237	if (!sk->sk_lock.owned)
2238		/*
2239		 * Note : We must disable BH
2240		 */
2241		return false;
2242
2243	__lock_sock(sk);
2244	sk->sk_lock.owned = 1;
2245	spin_unlock(&sk->sk_lock.slock);
2246	/*
2247	 * The sk_lock has mutex_lock() semantics here:
2248	 */
2249	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2250	local_bh_enable();
2251	return true;
2252}
2253EXPORT_SYMBOL(lock_sock_fast);
2254
2255int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2256{
2257	struct timeval tv;
2258	if (!sock_flag(sk, SOCK_TIMESTAMP))
2259		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2260	tv = ktime_to_timeval(sk->sk_stamp);
2261	if (tv.tv_sec == -1)
2262		return -ENOENT;
2263	if (tv.tv_sec == 0) {
2264		sk->sk_stamp = ktime_get_real();
2265		tv = ktime_to_timeval(sk->sk_stamp);
2266	}
2267	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2268}
2269EXPORT_SYMBOL(sock_get_timestamp);
2270
2271int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2272{
2273	struct timespec ts;
2274	if (!sock_flag(sk, SOCK_TIMESTAMP))
2275		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2276	ts = ktime_to_timespec(sk->sk_stamp);
2277	if (ts.tv_sec == -1)
2278		return -ENOENT;
2279	if (ts.tv_sec == 0) {
2280		sk->sk_stamp = ktime_get_real();
2281		ts = ktime_to_timespec(sk->sk_stamp);
2282	}
2283	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2284}
2285EXPORT_SYMBOL(sock_get_timestampns);
2286
2287void sock_enable_timestamp(struct sock *sk, int flag)
2288{
2289	if (!sock_flag(sk, flag)) {
2290		unsigned long previous_flags = sk->sk_flags;
2291
2292		sock_set_flag(sk, flag);
2293		/*
2294		 * we just set one of the two flags which require net
2295		 * time stamping, but time stamping might have been on
2296		 * already because of the other one
2297		 */
2298		if (!(previous_flags & SK_FLAGS_TIMESTAMP))
2299			net_enable_timestamp();
2300	}
2301}
2302
2303/*
2304 *	Get a socket option on an socket.
2305 *
2306 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2307 *	asynchronous errors should be reported by getsockopt. We assume
2308 *	this means if you specify SO_ERROR (otherwise whats the point of it).
2309 */
2310int sock_common_getsockopt(struct socket *sock, int level, int optname,
2311			   char __user *optval, int __user *optlen)
2312{
2313	struct sock *sk = sock->sk;
2314
2315	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2316}
2317EXPORT_SYMBOL(sock_common_getsockopt);
2318
2319#ifdef CONFIG_COMPAT
2320int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2321				  char __user *optval, int __user *optlen)
2322{
2323	struct sock *sk = sock->sk;
2324
2325	if (sk->sk_prot->compat_getsockopt != NULL)
2326		return sk->sk_prot->compat_getsockopt(sk, level, optname,
2327						      optval, optlen);
2328	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2329}
2330EXPORT_SYMBOL(compat_sock_common_getsockopt);
2331#endif
2332
2333int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2334			struct msghdr *msg, size_t size, int flags)
2335{
2336	struct sock *sk = sock->sk;
2337	int addr_len = 0;
2338	int err;
2339
2340	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2341				   flags & ~MSG_DONTWAIT, &addr_len);
2342	if (err >= 0)
2343		msg->msg_namelen = addr_len;
2344	return err;
2345}
2346EXPORT_SYMBOL(sock_common_recvmsg);
2347
2348/*
2349 *	Set socket options on an inet socket.
2350 */
2351int sock_common_setsockopt(struct socket *sock, int level, int optname,
2352			   char __user *optval, unsigned int optlen)
2353{
2354	struct sock *sk = sock->sk;
2355
2356	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2357}
2358EXPORT_SYMBOL(sock_common_setsockopt);
2359
2360#ifdef CONFIG_COMPAT
2361int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2362				  char __user *optval, unsigned int optlen)
2363{
2364	struct sock *sk = sock->sk;
2365
2366	if (sk->sk_prot->compat_setsockopt != NULL)
2367		return sk->sk_prot->compat_setsockopt(sk, level, optname,
2368						      optval, optlen);
2369	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2370}
2371EXPORT_SYMBOL(compat_sock_common_setsockopt);
2372#endif
2373
2374void sk_common_release(struct sock *sk)
2375{
2376	if (sk->sk_prot->destroy)
2377		sk->sk_prot->destroy(sk);
2378
2379	/*
2380	 * Observation: when sock_common_release is called, processes have
2381	 * no access to socket. But net still has.
2382	 * Step one, detach it from networking:
2383	 *
2384	 * A. Remove from hash tables.
2385	 */
2386
2387	sk->sk_prot->unhash(sk);
2388
2389	/*
2390	 * In this point socket cannot receive new packets, but it is possible
2391	 * that some packets are in flight because some CPU runs receiver and
2392	 * did hash table lookup before we unhashed socket. They will achieve
2393	 * receive queue and will be purged by socket destructor.
2394	 *
2395	 * Also we still have packets pending on receive queue and probably,
2396	 * our own packets waiting in device queues. sock_destroy will drain
2397	 * receive queue, but transmitted packets will delay socket destruction
2398	 * until the last reference will be released.
2399	 */
2400
2401	sock_orphan(sk);
2402
2403	xfrm_sk_free_policy(sk);
2404
2405	sk_refcnt_debug_release(sk);
2406	sock_put(sk);
2407}
2408EXPORT_SYMBOL(sk_common_release);
2409
2410#ifdef CONFIG_PROC_FS
2411#define PROTO_INUSE_NR	64	/* should be enough for the first time */
2412struct prot_inuse {
2413	int val[PROTO_INUSE_NR];
2414};
2415
2416static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2417
2418#ifdef CONFIG_NET_NS
2419void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2420{
2421	__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2422}
2423EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2424
2425int sock_prot_inuse_get(struct net *net, struct proto *prot)
2426{
2427	int cpu, idx = prot->inuse_idx;
2428	int res = 0;
2429
2430	for_each_possible_cpu(cpu)
2431		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2432
2433	return res >= 0 ? res : 0;
2434}
2435EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2436
2437static int __net_init sock_inuse_init_net(struct net *net)
2438{
2439	net->core.inuse = alloc_percpu(struct prot_inuse);
2440	return net->core.inuse ? 0 : -ENOMEM;
2441}
2442
2443static void __net_exit sock_inuse_exit_net(struct net *net)
2444{
2445	free_percpu(net->core.inuse);
2446}
2447
2448static struct pernet_operations net_inuse_ops = {
2449	.init = sock_inuse_init_net,
2450	.exit = sock_inuse_exit_net,
2451};
2452
2453static __init int net_inuse_init(void)
2454{
2455	if (register_pernet_subsys(&net_inuse_ops))
2456		panic("Cannot initialize net inuse counters");
2457
2458	return 0;
2459}
2460
2461core_initcall(net_inuse_init);
2462#else
2463static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2464
2465void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2466{
2467	__this_cpu_add(prot_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(prot_inuse, cpu).val[idx];
2478
2479	return res >= 0 ? res : 0;
2480}
2481EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2482#endif
2483
2484static void assign_proto_idx(struct proto *prot)
2485{
2486	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2487
2488	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2489		pr_err("PROTO_INUSE_NR exhausted\n");
2490		return;
2491	}
2492
2493	set_bit(prot->inuse_idx, proto_inuse_idx);
2494}
2495
2496static void release_proto_idx(struct proto *prot)
2497{
2498	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2499		clear_bit(prot->inuse_idx, proto_inuse_idx);
2500}
2501#else
2502static inline void assign_proto_idx(struct proto *prot)
2503{
2504}
2505
2506static inline void release_proto_idx(struct proto *prot)
2507{
2508}
2509#endif
2510
2511int proto_register(struct proto *prot, int alloc_slab)
2512{
2513	if (alloc_slab) {
2514		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2515					SLAB_HWCACHE_ALIGN | prot->slab_flags,
2516					NULL);
2517
2518		if (prot->slab == NULL) {
2519			pr_crit("%s: Can't create sock SLAB cache!\n",
2520				prot->name);
2521			goto out;
2522		}
2523
2524		if (prot->rsk_prot != NULL) {
2525			prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2526			if (prot->rsk_prot->slab_name == NULL)
2527				goto out_free_sock_slab;
2528
2529			prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2530								 prot->rsk_prot->obj_size, 0,
2531								 SLAB_HWCACHE_ALIGN, NULL);
2532
2533			if (prot->rsk_prot->slab == NULL) {
2534				pr_crit("%s: Can't create request sock SLAB cache!\n",
2535					prot->name);
2536				goto out_free_request_sock_slab_name;
2537			}
2538		}
2539
2540		if (prot->twsk_prot != NULL) {
2541			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2542
2543			if (prot->twsk_prot->twsk_slab_name == NULL)
2544				goto out_free_request_sock_slab;
2545
2546			prot->twsk_prot->twsk_slab =
2547				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2548						  prot->twsk_prot->twsk_obj_size,
2549						  0,
2550						  SLAB_HWCACHE_ALIGN |
2551							prot->slab_flags,
2552						  NULL);
2553			if (prot->twsk_prot->twsk_slab == NULL)
2554				goto out_free_timewait_sock_slab_name;
2555		}
2556	}
2557
2558	mutex_lock(&proto_list_mutex);
2559	list_add(&prot->node, &proto_list);
2560	assign_proto_idx(prot);
2561	mutex_unlock(&proto_list_mutex);
2562	return 0;
2563
2564out_free_timewait_sock_slab_name:
2565	kfree(prot->twsk_prot->twsk_slab_name);
2566out_free_request_sock_slab:
2567	if (prot->rsk_prot && prot->rsk_prot->slab) {
2568		kmem_cache_destroy(prot->rsk_prot->slab);
2569		prot->rsk_prot->slab = NULL;
2570	}
2571out_free_request_sock_slab_name:
2572	if (prot->rsk_prot)
2573		kfree(prot->rsk_prot->slab_name);
2574out_free_sock_slab:
2575	kmem_cache_destroy(prot->slab);
2576	prot->slab = NULL;
2577out:
2578	return -ENOBUFS;
2579}
2580EXPORT_SYMBOL(proto_register);
2581
2582void proto_unregister(struct proto *prot)
2583{
2584	mutex_lock(&proto_list_mutex);
2585	release_proto_idx(prot);
2586	list_del(&prot->node);
2587	mutex_unlock(&proto_list_mutex);
2588
2589	if (prot->slab != NULL) {
2590		kmem_cache_destroy(prot->slab);
2591		prot->slab = NULL;
2592	}
2593
2594	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2595		kmem_cache_destroy(prot->rsk_prot->slab);
2596		kfree(prot->rsk_prot->slab_name);
2597		prot->rsk_prot->slab = NULL;
2598	}
2599
2600	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2601		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2602		kfree(prot->twsk_prot->twsk_slab_name);
2603		prot->twsk_prot->twsk_slab = NULL;
2604	}
2605}
2606EXPORT_SYMBOL(proto_unregister);
2607
2608#ifdef CONFIG_PROC_FS
2609static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2610	__acquires(proto_list_mutex)
2611{
2612	mutex_lock(&proto_list_mutex);
2613	return seq_list_start_head(&proto_list, *pos);
2614}
2615
2616static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2617{
2618	return seq_list_next(v, &proto_list, pos);
2619}
2620
2621static void proto_seq_stop(struct seq_file *seq, void *v)
2622	__releases(proto_list_mutex)
2623{
2624	mutex_unlock(&proto_list_mutex);
2625}
2626
2627static char proto_method_implemented(const void *method)
2628{
2629	return method == NULL ? 'n' : 'y';
2630}
2631static long sock_prot_memory_allocated(struct proto *proto)
2632{
2633	return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2634}
2635
2636static char *sock_prot_memory_pressure(struct proto *proto)
2637{
2638	return proto->memory_pressure != NULL ?
2639	proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2640}
2641
2642static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2643{
2644
2645	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
2646			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2647		   proto->name,
2648		   proto->obj_size,
2649		   sock_prot_inuse_get(seq_file_net(seq), proto),
2650		   sock_prot_memory_allocated(proto),
2651		   sock_prot_memory_pressure(proto),
2652		   proto->max_header,
2653		   proto->slab == NULL ? "no" : "yes",
2654		   module_name(proto->owner),
2655		   proto_method_implemented(proto->close),
2656		   proto_method_implemented(proto->connect),
2657		   proto_method_implemented(proto->disconnect),
2658		   proto_method_implemented(proto->accept),
2659		   proto_method_implemented(proto->ioctl),
2660		   proto_method_implemented(proto->init),
2661		   proto_method_implemented(proto->destroy),
2662		   proto_method_implemented(proto->shutdown),
2663		   proto_method_implemented(proto->setsockopt),
2664		   proto_method_implemented(proto->getsockopt),
2665		   proto_method_implemented(proto->sendmsg),
2666		   proto_method_implemented(proto->recvmsg),
2667		   proto_method_implemented(proto->sendpage),
2668		   proto_method_implemented(proto->bind),
2669		   proto_method_implemented(proto->backlog_rcv),
2670		   proto_method_implemented(proto->hash),
2671		   proto_method_implemented(proto->unhash),
2672		   proto_method_implemented(proto->get_port),
2673		   proto_method_implemented(proto->enter_memory_pressure));
2674}
2675
2676static int proto_seq_show(struct seq_file *seq, void *v)
2677{
2678	if (v == &proto_list)
2679		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2680			   "protocol",
2681			   "size",
2682			   "sockets",
2683			   "memory",
2684			   "press",
2685			   "maxhdr",
2686			   "slab",
2687			   "module",
2688			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2689	else
2690		proto_seq_printf(seq, list_entry(v, struct proto, node));
2691	return 0;
2692}
2693
2694static const struct seq_operations proto_seq_ops = {
2695	.start  = proto_seq_start,
2696	.next   = proto_seq_next,
2697	.stop   = proto_seq_stop,
2698	.show   = proto_seq_show,
2699};
2700
2701static int proto_seq_open(struct inode *inode, struct file *file)
2702{
2703	return seq_open_net(inode, file, &proto_seq_ops,
2704			    sizeof(struct seq_net_private));
2705}
2706
2707static const struct file_operations proto_seq_fops = {
2708	.owner		= THIS_MODULE,
2709	.open		= proto_seq_open,
2710	.read		= seq_read,
2711	.llseek		= seq_lseek,
2712	.release	= seq_release_net,
2713};
2714
2715static __net_init int proto_init_net(struct net *net)
2716{
2717	if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2718		return -ENOMEM;
2719
2720	return 0;
2721}
2722
2723static __net_exit void proto_exit_net(struct net *net)
2724{
2725	proc_net_remove(net, "protocols");
2726}
2727
2728
2729static __net_initdata struct pernet_operations proto_net_ops = {
2730	.init = proto_init_net,
2731	.exit = proto_exit_net,
2732};
2733
2734static int __init proto_init(void)
2735{
2736	return register_pernet_subsys(&proto_net_ops);
2737}
2738
2739subsys_initcall(proto_init);
2740
2741#endif /* PROC_FS */
2742