sock.c revision 0fd7bac6b6157eed6cf0cb86a1e88ba29e57c033
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#include <linux/capability.h>
93#include <linux/errno.h>
94#include <linux/types.h>
95#include <linux/socket.h>
96#include <linux/in.h>
97#include <linux/kernel.h>
98#include <linux/module.h>
99#include <linux/proc_fs.h>
100#include <linux/seq_file.h>
101#include <linux/sched.h>
102#include <linux/timer.h>
103#include <linux/string.h>
104#include <linux/sockios.h>
105#include <linux/net.h>
106#include <linux/mm.h>
107#include <linux/slab.h>
108#include <linux/interrupt.h>
109#include <linux/poll.h>
110#include <linux/tcp.h>
111#include <linux/init.h>
112#include <linux/highmem.h>
113#include <linux/user_namespace.h>
114
115#include <asm/uaccess.h>
116#include <asm/system.h>
117
118#include <linux/netdevice.h>
119#include <net/protocol.h>
120#include <linux/skbuff.h>
121#include <net/net_namespace.h>
122#include <net/request_sock.h>
123#include <net/sock.h>
124#include <linux/net_tstamp.h>
125#include <net/xfrm.h>
126#include <linux/ipsec.h>
127#include <net/cls_cgroup.h>
128
129#include <linux/filter.h>
130
131#include <trace/events/sock.h>
132
133#ifdef CONFIG_INET
134#include <net/tcp.h>
135#endif
136
137/*
138 * Each address family might have different locking rules, so we have
139 * one slock key per address family:
140 */
141static struct lock_class_key af_family_keys[AF_MAX];
142static struct lock_class_key af_family_slock_keys[AF_MAX];
143
144/*
145 * Make lock validator output more readable. (we pre-construct these
146 * strings build-time, so that runtime initialization of socket
147 * locks is fast):
148 */
149static const char *const af_family_key_strings[AF_MAX+1] = {
150  "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX"     , "sk_lock-AF_INET"     ,
151  "sk_lock-AF_AX25"  , "sk_lock-AF_IPX"      , "sk_lock-AF_APPLETALK",
152  "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE"   , "sk_lock-AF_ATMPVC"   ,
153  "sk_lock-AF_X25"   , "sk_lock-AF_INET6"    , "sk_lock-AF_ROSE"     ,
154  "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI"  , "sk_lock-AF_SECURITY" ,
155  "sk_lock-AF_KEY"   , "sk_lock-AF_NETLINK"  , "sk_lock-AF_PACKET"   ,
156  "sk_lock-AF_ASH"   , "sk_lock-AF_ECONET"   , "sk_lock-AF_ATMSVC"   ,
157  "sk_lock-AF_RDS"   , "sk_lock-AF_SNA"      , "sk_lock-AF_IRDA"     ,
158  "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE"  , "sk_lock-AF_LLC"      ,
159  "sk_lock-27"       , "sk_lock-28"          , "sk_lock-AF_CAN"      ,
160  "sk_lock-AF_TIPC"  , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV"        ,
161  "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN"     , "sk_lock-AF_PHONET"   ,
162  "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG"      ,
163  "sk_lock-AF_NFC"   , "sk_lock-AF_MAX"
164};
165static const char *const af_family_slock_key_strings[AF_MAX+1] = {
166  "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
167  "slock-AF_AX25"  , "slock-AF_IPX"      , "slock-AF_APPLETALK",
168  "slock-AF_NETROM", "slock-AF_BRIDGE"   , "slock-AF_ATMPVC"   ,
169  "slock-AF_X25"   , "slock-AF_INET6"    , "slock-AF_ROSE"     ,
170  "slock-AF_DECnet", "slock-AF_NETBEUI"  , "slock-AF_SECURITY" ,
171  "slock-AF_KEY"   , "slock-AF_NETLINK"  , "slock-AF_PACKET"   ,
172  "slock-AF_ASH"   , "slock-AF_ECONET"   , "slock-AF_ATMSVC"   ,
173  "slock-AF_RDS"   , "slock-AF_SNA"      , "slock-AF_IRDA"     ,
174  "slock-AF_PPPOX" , "slock-AF_WANPIPE"  , "slock-AF_LLC"      ,
175  "slock-27"       , "slock-28"          , "slock-AF_CAN"      ,
176  "slock-AF_TIPC"  , "slock-AF_BLUETOOTH", "slock-AF_IUCV"     ,
177  "slock-AF_RXRPC" , "slock-AF_ISDN"     , "slock-AF_PHONET"   ,
178  "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG"      ,
179  "slock-AF_NFC"   , "slock-AF_MAX"
180};
181static const char *const af_family_clock_key_strings[AF_MAX+1] = {
182  "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
183  "clock-AF_AX25"  , "clock-AF_IPX"      , "clock-AF_APPLETALK",
184  "clock-AF_NETROM", "clock-AF_BRIDGE"   , "clock-AF_ATMPVC"   ,
185  "clock-AF_X25"   , "clock-AF_INET6"    , "clock-AF_ROSE"     ,
186  "clock-AF_DECnet", "clock-AF_NETBEUI"  , "clock-AF_SECURITY" ,
187  "clock-AF_KEY"   , "clock-AF_NETLINK"  , "clock-AF_PACKET"   ,
188  "clock-AF_ASH"   , "clock-AF_ECONET"   , "clock-AF_ATMSVC"   ,
189  "clock-AF_RDS"   , "clock-AF_SNA"      , "clock-AF_IRDA"     ,
190  "clock-AF_PPPOX" , "clock-AF_WANPIPE"  , "clock-AF_LLC"      ,
191  "clock-27"       , "clock-28"          , "clock-AF_CAN"      ,
192  "clock-AF_TIPC"  , "clock-AF_BLUETOOTH", "clock-AF_IUCV"     ,
193  "clock-AF_RXRPC" , "clock-AF_ISDN"     , "clock-AF_PHONET"   ,
194  "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG"      ,
195  "clock-AF_NFC"   , "clock-AF_MAX"
196};
197
198/*
199 * sk_callback_lock locking rules are per-address-family,
200 * so split the lock classes by using a per-AF key:
201 */
202static struct lock_class_key af_callback_keys[AF_MAX];
203
204/* Take into consideration the size of the struct sk_buff overhead in the
205 * determination of these values, since that is non-constant across
206 * platforms.  This makes socket queueing behavior and performance
207 * not depend upon such differences.
208 */
209#define _SK_MEM_PACKETS		256
210#define _SK_MEM_OVERHEAD	SKB_TRUESIZE(256)
211#define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
212#define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
213
214/* Run time adjustable parameters. */
215__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
216__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
217__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
218__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
219
220/* Maximal space eaten by iovec or ancillary data plus some space */
221int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
222EXPORT_SYMBOL(sysctl_optmem_max);
223
224#if defined(CONFIG_CGROUPS) && !defined(CONFIG_NET_CLS_CGROUP)
225int net_cls_subsys_id = -1;
226EXPORT_SYMBOL_GPL(net_cls_subsys_id);
227#endif
228
229static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
230{
231	struct timeval tv;
232
233	if (optlen < sizeof(tv))
234		return -EINVAL;
235	if (copy_from_user(&tv, optval, sizeof(tv)))
236		return -EFAULT;
237	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
238		return -EDOM;
239
240	if (tv.tv_sec < 0) {
241		static int warned __read_mostly;
242
243		*timeo_p = 0;
244		if (warned < 10 && net_ratelimit()) {
245			warned++;
246			printk(KERN_INFO "sock_set_timeout: `%s' (pid %d) "
247			       "tries to set negative timeout\n",
248				current->comm, task_pid_nr(current));
249		}
250		return 0;
251	}
252	*timeo_p = MAX_SCHEDULE_TIMEOUT;
253	if (tv.tv_sec == 0 && tv.tv_usec == 0)
254		return 0;
255	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
256		*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
257	return 0;
258}
259
260static void sock_warn_obsolete_bsdism(const char *name)
261{
262	static int warned;
263	static char warncomm[TASK_COMM_LEN];
264	if (strcmp(warncomm, current->comm) && warned < 5) {
265		strcpy(warncomm,  current->comm);
266		printk(KERN_WARNING "process `%s' is using obsolete "
267		       "%s SO_BSDCOMPAT\n", warncomm, name);
268		warned++;
269	}
270}
271
272static void sock_disable_timestamp(struct sock *sk, int flag)
273{
274	if (sock_flag(sk, flag)) {
275		sock_reset_flag(sk, flag);
276		if (!sock_flag(sk, SOCK_TIMESTAMP) &&
277		    !sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE)) {
278			net_disable_timestamp();
279		}
280	}
281}
282
283
284int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
285{
286	int err;
287	int skb_len;
288	unsigned long flags;
289	struct sk_buff_head *list = &sk->sk_receive_queue;
290
291	if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
292		atomic_inc(&sk->sk_drops);
293		trace_sock_rcvqueue_full(sk, skb);
294		return -ENOMEM;
295	}
296
297	err = sk_filter(sk, skb);
298	if (err)
299		return err;
300
301	if (!sk_rmem_schedule(sk, skb->truesize)) {
302		atomic_inc(&sk->sk_drops);
303		return -ENOBUFS;
304	}
305
306	skb->dev = NULL;
307	skb_set_owner_r(skb, sk);
308
309	/* Cache the SKB length before we tack it onto the receive
310	 * queue.  Once it is added it no longer belongs to us and
311	 * may be freed by other threads of control pulling packets
312	 * from the queue.
313	 */
314	skb_len = skb->len;
315
316	/* we escape from rcu protected region, make sure we dont leak
317	 * a norefcounted dst
318	 */
319	skb_dst_force(skb);
320
321	spin_lock_irqsave(&list->lock, flags);
322	skb->dropcount = atomic_read(&sk->sk_drops);
323	__skb_queue_tail(list, skb);
324	spin_unlock_irqrestore(&list->lock, flags);
325
326	if (!sock_flag(sk, SOCK_DEAD))
327		sk->sk_data_ready(sk, skb_len);
328	return 0;
329}
330EXPORT_SYMBOL(sock_queue_rcv_skb);
331
332int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
333{
334	int rc = NET_RX_SUCCESS;
335
336	if (sk_filter(sk, skb))
337		goto discard_and_relse;
338
339	skb->dev = NULL;
340
341	if (sk_rcvqueues_full(sk, skb)) {
342		atomic_inc(&sk->sk_drops);
343		goto discard_and_relse;
344	}
345	if (nested)
346		bh_lock_sock_nested(sk);
347	else
348		bh_lock_sock(sk);
349	if (!sock_owned_by_user(sk)) {
350		/*
351		 * trylock + unlock semantics:
352		 */
353		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
354
355		rc = sk_backlog_rcv(sk, skb);
356
357		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
358	} else if (sk_add_backlog(sk, skb)) {
359		bh_unlock_sock(sk);
360		atomic_inc(&sk->sk_drops);
361		goto discard_and_relse;
362	}
363
364	bh_unlock_sock(sk);
365out:
366	sock_put(sk);
367	return rc;
368discard_and_relse:
369	kfree_skb(skb);
370	goto out;
371}
372EXPORT_SYMBOL(sk_receive_skb);
373
374void sk_reset_txq(struct sock *sk)
375{
376	sk_tx_queue_clear(sk);
377}
378EXPORT_SYMBOL(sk_reset_txq);
379
380struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
381{
382	struct dst_entry *dst = __sk_dst_get(sk);
383
384	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
385		sk_tx_queue_clear(sk);
386		RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
387		dst_release(dst);
388		return NULL;
389	}
390
391	return dst;
392}
393EXPORT_SYMBOL(__sk_dst_check);
394
395struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
396{
397	struct dst_entry *dst = sk_dst_get(sk);
398
399	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
400		sk_dst_reset(sk);
401		dst_release(dst);
402		return NULL;
403	}
404
405	return dst;
406}
407EXPORT_SYMBOL(sk_dst_check);
408
409static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
410{
411	int ret = -ENOPROTOOPT;
412#ifdef CONFIG_NETDEVICES
413	struct net *net = sock_net(sk);
414	char devname[IFNAMSIZ];
415	int index;
416
417	/* Sorry... */
418	ret = -EPERM;
419	if (!capable(CAP_NET_RAW))
420		goto out;
421
422	ret = -EINVAL;
423	if (optlen < 0)
424		goto out;
425
426	/* Bind this socket to a particular device like "eth0",
427	 * as specified in the passed interface name. If the
428	 * name is "" or the option length is zero the socket
429	 * is not bound.
430	 */
431	if (optlen > IFNAMSIZ - 1)
432		optlen = IFNAMSIZ - 1;
433	memset(devname, 0, sizeof(devname));
434
435	ret = -EFAULT;
436	if (copy_from_user(devname, optval, optlen))
437		goto out;
438
439	index = 0;
440	if (devname[0] != '\0') {
441		struct net_device *dev;
442
443		rcu_read_lock();
444		dev = dev_get_by_name_rcu(net, devname);
445		if (dev)
446			index = dev->ifindex;
447		rcu_read_unlock();
448		ret = -ENODEV;
449		if (!dev)
450			goto out;
451	}
452
453	lock_sock(sk);
454	sk->sk_bound_dev_if = index;
455	sk_dst_reset(sk);
456	release_sock(sk);
457
458	ret = 0;
459
460out:
461#endif
462
463	return ret;
464}
465
466static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
467{
468	if (valbool)
469		sock_set_flag(sk, bit);
470	else
471		sock_reset_flag(sk, bit);
472}
473
474/*
475 *	This is meant for all protocols to use and covers goings on
476 *	at the socket level. Everything here is generic.
477 */
478
479int sock_setsockopt(struct socket *sock, int level, int optname,
480		    char __user *optval, unsigned int optlen)
481{
482	struct sock *sk = sock->sk;
483	int val;
484	int valbool;
485	struct linger ling;
486	int ret = 0;
487
488	/*
489	 *	Options without arguments
490	 */
491
492	if (optname == SO_BINDTODEVICE)
493		return sock_bindtodevice(sk, optval, optlen);
494
495	if (optlen < sizeof(int))
496		return -EINVAL;
497
498	if (get_user(val, (int __user *)optval))
499		return -EFAULT;
500
501	valbool = val ? 1 : 0;
502
503	lock_sock(sk);
504
505	switch (optname) {
506	case SO_DEBUG:
507		if (val && !capable(CAP_NET_ADMIN))
508			ret = -EACCES;
509		else
510			sock_valbool_flag(sk, SOCK_DBG, valbool);
511		break;
512	case SO_REUSEADDR:
513		sk->sk_reuse = valbool;
514		break;
515	case SO_TYPE:
516	case SO_PROTOCOL:
517	case SO_DOMAIN:
518	case SO_ERROR:
519		ret = -ENOPROTOOPT;
520		break;
521	case SO_DONTROUTE:
522		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
523		break;
524	case SO_BROADCAST:
525		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
526		break;
527	case SO_SNDBUF:
528		/* Don't error on this BSD doesn't and if you think
529		   about it this is right. Otherwise apps have to
530		   play 'guess the biggest size' games. RCVBUF/SNDBUF
531		   are treated in BSD as hints */
532
533		if (val > sysctl_wmem_max)
534			val = sysctl_wmem_max;
535set_sndbuf:
536		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
537		if ((val * 2) < SOCK_MIN_SNDBUF)
538			sk->sk_sndbuf = SOCK_MIN_SNDBUF;
539		else
540			sk->sk_sndbuf = val * 2;
541
542		/*
543		 *	Wake up sending tasks if we
544		 *	upped the value.
545		 */
546		sk->sk_write_space(sk);
547		break;
548
549	case SO_SNDBUFFORCE:
550		if (!capable(CAP_NET_ADMIN)) {
551			ret = -EPERM;
552			break;
553		}
554		goto set_sndbuf;
555
556	case SO_RCVBUF:
557		/* Don't error on this BSD doesn't and if you think
558		   about it this is right. Otherwise apps have to
559		   play 'guess the biggest size' games. RCVBUF/SNDBUF
560		   are treated in BSD as hints */
561
562		if (val > sysctl_rmem_max)
563			val = sysctl_rmem_max;
564set_rcvbuf:
565		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
566		/*
567		 * We double it on the way in to account for
568		 * "struct sk_buff" etc. overhead.   Applications
569		 * assume that the SO_RCVBUF setting they make will
570		 * allow that much actual data to be received on that
571		 * socket.
572		 *
573		 * Applications are unaware that "struct sk_buff" and
574		 * other overheads allocate from the receive buffer
575		 * during socket buffer allocation.
576		 *
577		 * And after considering the possible alternatives,
578		 * returning the value we actually used in getsockopt
579		 * is the most desirable behavior.
580		 */
581		if ((val * 2) < SOCK_MIN_RCVBUF)
582			sk->sk_rcvbuf = SOCK_MIN_RCVBUF;
583		else
584			sk->sk_rcvbuf = val * 2;
585		break;
586
587	case SO_RCVBUFFORCE:
588		if (!capable(CAP_NET_ADMIN)) {
589			ret = -EPERM;
590			break;
591		}
592		goto set_rcvbuf;
593
594	case SO_KEEPALIVE:
595#ifdef CONFIG_INET
596		if (sk->sk_protocol == IPPROTO_TCP)
597			tcp_set_keepalive(sk, valbool);
598#endif
599		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
600		break;
601
602	case SO_OOBINLINE:
603		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
604		break;
605
606	case SO_NO_CHECK:
607		sk->sk_no_check = valbool;
608		break;
609
610	case SO_PRIORITY:
611		if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
612			sk->sk_priority = val;
613		else
614			ret = -EPERM;
615		break;
616
617	case SO_LINGER:
618		if (optlen < sizeof(ling)) {
619			ret = -EINVAL;	/* 1003.1g */
620			break;
621		}
622		if (copy_from_user(&ling, optval, sizeof(ling))) {
623			ret = -EFAULT;
624			break;
625		}
626		if (!ling.l_onoff)
627			sock_reset_flag(sk, SOCK_LINGER);
628		else {
629#if (BITS_PER_LONG == 32)
630			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
631				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
632			else
633#endif
634				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
635			sock_set_flag(sk, SOCK_LINGER);
636		}
637		break;
638
639	case SO_BSDCOMPAT:
640		sock_warn_obsolete_bsdism("setsockopt");
641		break;
642
643	case SO_PASSCRED:
644		if (valbool)
645			set_bit(SOCK_PASSCRED, &sock->flags);
646		else
647			clear_bit(SOCK_PASSCRED, &sock->flags);
648		break;
649
650	case SO_TIMESTAMP:
651	case SO_TIMESTAMPNS:
652		if (valbool)  {
653			if (optname == SO_TIMESTAMP)
654				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
655			else
656				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
657			sock_set_flag(sk, SOCK_RCVTSTAMP);
658			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
659		} else {
660			sock_reset_flag(sk, SOCK_RCVTSTAMP);
661			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
662		}
663		break;
664
665	case SO_TIMESTAMPING:
666		if (val & ~SOF_TIMESTAMPING_MASK) {
667			ret = -EINVAL;
668			break;
669		}
670		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE,
671				  val & SOF_TIMESTAMPING_TX_HARDWARE);
672		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE,
673				  val & SOF_TIMESTAMPING_TX_SOFTWARE);
674		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE,
675				  val & SOF_TIMESTAMPING_RX_HARDWARE);
676		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
677			sock_enable_timestamp(sk,
678					      SOCK_TIMESTAMPING_RX_SOFTWARE);
679		else
680			sock_disable_timestamp(sk,
681					       SOCK_TIMESTAMPING_RX_SOFTWARE);
682		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE,
683				  val & SOF_TIMESTAMPING_SOFTWARE);
684		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE,
685				  val & SOF_TIMESTAMPING_SYS_HARDWARE);
686		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE,
687				  val & SOF_TIMESTAMPING_RAW_HARDWARE);
688		break;
689
690	case SO_RCVLOWAT:
691		if (val < 0)
692			val = INT_MAX;
693		sk->sk_rcvlowat = val ? : 1;
694		break;
695
696	case SO_RCVTIMEO:
697		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
698		break;
699
700	case SO_SNDTIMEO:
701		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
702		break;
703
704	case SO_ATTACH_FILTER:
705		ret = -EINVAL;
706		if (optlen == sizeof(struct sock_fprog)) {
707			struct sock_fprog fprog;
708
709			ret = -EFAULT;
710			if (copy_from_user(&fprog, optval, sizeof(fprog)))
711				break;
712
713			ret = sk_attach_filter(&fprog, sk);
714		}
715		break;
716
717	case SO_DETACH_FILTER:
718		ret = sk_detach_filter(sk);
719		break;
720
721	case SO_PASSSEC:
722		if (valbool)
723			set_bit(SOCK_PASSSEC, &sock->flags);
724		else
725			clear_bit(SOCK_PASSSEC, &sock->flags);
726		break;
727	case SO_MARK:
728		if (!capable(CAP_NET_ADMIN))
729			ret = -EPERM;
730		else
731			sk->sk_mark = val;
732		break;
733
734		/* We implement the SO_SNDLOWAT etc to
735		   not be settable (1003.1g 5.3) */
736	case SO_RXQ_OVFL:
737		sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
738		break;
739	default:
740		ret = -ENOPROTOOPT;
741		break;
742	}
743	release_sock(sk);
744	return ret;
745}
746EXPORT_SYMBOL(sock_setsockopt);
747
748
749void cred_to_ucred(struct pid *pid, const struct cred *cred,
750		   struct ucred *ucred)
751{
752	ucred->pid = pid_vnr(pid);
753	ucred->uid = ucred->gid = -1;
754	if (cred) {
755		struct user_namespace *current_ns = current_user_ns();
756
757		ucred->uid = user_ns_map_uid(current_ns, cred, cred->euid);
758		ucred->gid = user_ns_map_gid(current_ns, cred, cred->egid);
759	}
760}
761EXPORT_SYMBOL_GPL(cred_to_ucred);
762
763int sock_getsockopt(struct socket *sock, int level, int optname,
764		    char __user *optval, int __user *optlen)
765{
766	struct sock *sk = sock->sk;
767
768	union {
769		int val;
770		struct linger ling;
771		struct timeval tm;
772	} v;
773
774	int lv = sizeof(int);
775	int len;
776
777	if (get_user(len, optlen))
778		return -EFAULT;
779	if (len < 0)
780		return -EINVAL;
781
782	memset(&v, 0, sizeof(v));
783
784	switch (optname) {
785	case SO_DEBUG:
786		v.val = sock_flag(sk, SOCK_DBG);
787		break;
788
789	case SO_DONTROUTE:
790		v.val = sock_flag(sk, SOCK_LOCALROUTE);
791		break;
792
793	case SO_BROADCAST:
794		v.val = !!sock_flag(sk, SOCK_BROADCAST);
795		break;
796
797	case SO_SNDBUF:
798		v.val = sk->sk_sndbuf;
799		break;
800
801	case SO_RCVBUF:
802		v.val = sk->sk_rcvbuf;
803		break;
804
805	case SO_REUSEADDR:
806		v.val = sk->sk_reuse;
807		break;
808
809	case SO_KEEPALIVE:
810		v.val = !!sock_flag(sk, SOCK_KEEPOPEN);
811		break;
812
813	case SO_TYPE:
814		v.val = sk->sk_type;
815		break;
816
817	case SO_PROTOCOL:
818		v.val = sk->sk_protocol;
819		break;
820
821	case SO_DOMAIN:
822		v.val = sk->sk_family;
823		break;
824
825	case SO_ERROR:
826		v.val = -sock_error(sk);
827		if (v.val == 0)
828			v.val = xchg(&sk->sk_err_soft, 0);
829		break;
830
831	case SO_OOBINLINE:
832		v.val = !!sock_flag(sk, SOCK_URGINLINE);
833		break;
834
835	case SO_NO_CHECK:
836		v.val = sk->sk_no_check;
837		break;
838
839	case SO_PRIORITY:
840		v.val = sk->sk_priority;
841		break;
842
843	case SO_LINGER:
844		lv		= sizeof(v.ling);
845		v.ling.l_onoff	= !!sock_flag(sk, SOCK_LINGER);
846		v.ling.l_linger	= sk->sk_lingertime / HZ;
847		break;
848
849	case SO_BSDCOMPAT:
850		sock_warn_obsolete_bsdism("getsockopt");
851		break;
852
853	case SO_TIMESTAMP:
854		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
855				!sock_flag(sk, SOCK_RCVTSTAMPNS);
856		break;
857
858	case SO_TIMESTAMPNS:
859		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
860		break;
861
862	case SO_TIMESTAMPING:
863		v.val = 0;
864		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
865			v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
866		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
867			v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
868		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
869			v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
870		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
871			v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
872		if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
873			v.val |= SOF_TIMESTAMPING_SOFTWARE;
874		if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
875			v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
876		if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
877			v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
878		break;
879
880	case SO_RCVTIMEO:
881		lv = sizeof(struct timeval);
882		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
883			v.tm.tv_sec = 0;
884			v.tm.tv_usec = 0;
885		} else {
886			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
887			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
888		}
889		break;
890
891	case SO_SNDTIMEO:
892		lv = sizeof(struct timeval);
893		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
894			v.tm.tv_sec = 0;
895			v.tm.tv_usec = 0;
896		} else {
897			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
898			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
899		}
900		break;
901
902	case SO_RCVLOWAT:
903		v.val = sk->sk_rcvlowat;
904		break;
905
906	case SO_SNDLOWAT:
907		v.val = 1;
908		break;
909
910	case SO_PASSCRED:
911		v.val = test_bit(SOCK_PASSCRED, &sock->flags) ? 1 : 0;
912		break;
913
914	case SO_PEERCRED:
915	{
916		struct ucred peercred;
917		if (len > sizeof(peercred))
918			len = sizeof(peercred);
919		cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
920		if (copy_to_user(optval, &peercred, len))
921			return -EFAULT;
922		goto lenout;
923	}
924
925	case SO_PEERNAME:
926	{
927		char address[128];
928
929		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
930			return -ENOTCONN;
931		if (lv < len)
932			return -EINVAL;
933		if (copy_to_user(optval, address, len))
934			return -EFAULT;
935		goto lenout;
936	}
937
938	/* Dubious BSD thing... Probably nobody even uses it, but
939	 * the UNIX standard wants it for whatever reason... -DaveM
940	 */
941	case SO_ACCEPTCONN:
942		v.val = sk->sk_state == TCP_LISTEN;
943		break;
944
945	case SO_PASSSEC:
946		v.val = test_bit(SOCK_PASSSEC, &sock->flags) ? 1 : 0;
947		break;
948
949	case SO_PEERSEC:
950		return security_socket_getpeersec_stream(sock, optval, optlen, len);
951
952	case SO_MARK:
953		v.val = sk->sk_mark;
954		break;
955
956	case SO_RXQ_OVFL:
957		v.val = !!sock_flag(sk, SOCK_RXQ_OVFL);
958		break;
959
960	default:
961		return -ENOPROTOOPT;
962	}
963
964	if (len > lv)
965		len = lv;
966	if (copy_to_user(optval, &v, len))
967		return -EFAULT;
968lenout:
969	if (put_user(len, optlen))
970		return -EFAULT;
971	return 0;
972}
973
974/*
975 * Initialize an sk_lock.
976 *
977 * (We also register the sk_lock with the lock validator.)
978 */
979static inline void sock_lock_init(struct sock *sk)
980{
981	sock_lock_init_class_and_name(sk,
982			af_family_slock_key_strings[sk->sk_family],
983			af_family_slock_keys + sk->sk_family,
984			af_family_key_strings[sk->sk_family],
985			af_family_keys + sk->sk_family);
986}
987
988/*
989 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
990 * even temporarly, because of RCU lookups. sk_node should also be left as is.
991 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
992 */
993static void sock_copy(struct sock *nsk, const struct sock *osk)
994{
995#ifdef CONFIG_SECURITY_NETWORK
996	void *sptr = nsk->sk_security;
997#endif
998	memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
999
1000	memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1001	       osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1002
1003#ifdef CONFIG_SECURITY_NETWORK
1004	nsk->sk_security = sptr;
1005	security_sk_clone(osk, nsk);
1006#endif
1007}
1008
1009/*
1010 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
1011 * un-modified. Special care is taken when initializing object to zero.
1012 */
1013static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1014{
1015	if (offsetof(struct sock, sk_node.next) != 0)
1016		memset(sk, 0, offsetof(struct sock, sk_node.next));
1017	memset(&sk->sk_node.pprev, 0,
1018	       size - offsetof(struct sock, sk_node.pprev));
1019}
1020
1021void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1022{
1023	unsigned long nulls1, nulls2;
1024
1025	nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1026	nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1027	if (nulls1 > nulls2)
1028		swap(nulls1, nulls2);
1029
1030	if (nulls1 != 0)
1031		memset((char *)sk, 0, nulls1);
1032	memset((char *)sk + nulls1 + sizeof(void *), 0,
1033	       nulls2 - nulls1 - sizeof(void *));
1034	memset((char *)sk + nulls2 + sizeof(void *), 0,
1035	       size - nulls2 - sizeof(void *));
1036}
1037EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1038
1039static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1040		int family)
1041{
1042	struct sock *sk;
1043	struct kmem_cache *slab;
1044
1045	slab = prot->slab;
1046	if (slab != NULL) {
1047		sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1048		if (!sk)
1049			return sk;
1050		if (priority & __GFP_ZERO) {
1051			if (prot->clear_sk)
1052				prot->clear_sk(sk, prot->obj_size);
1053			else
1054				sk_prot_clear_nulls(sk, prot->obj_size);
1055		}
1056	} else
1057		sk = kmalloc(prot->obj_size, priority);
1058
1059	if (sk != NULL) {
1060		kmemcheck_annotate_bitfield(sk, flags);
1061
1062		if (security_sk_alloc(sk, family, priority))
1063			goto out_free;
1064
1065		if (!try_module_get(prot->owner))
1066			goto out_free_sec;
1067		sk_tx_queue_clear(sk);
1068	}
1069
1070	return sk;
1071
1072out_free_sec:
1073	security_sk_free(sk);
1074out_free:
1075	if (slab != NULL)
1076		kmem_cache_free(slab, sk);
1077	else
1078		kfree(sk);
1079	return NULL;
1080}
1081
1082static void sk_prot_free(struct proto *prot, struct sock *sk)
1083{
1084	struct kmem_cache *slab;
1085	struct module *owner;
1086
1087	owner = prot->owner;
1088	slab = prot->slab;
1089
1090	security_sk_free(sk);
1091	if (slab != NULL)
1092		kmem_cache_free(slab, sk);
1093	else
1094		kfree(sk);
1095	module_put(owner);
1096}
1097
1098#ifdef CONFIG_CGROUPS
1099void sock_update_classid(struct sock *sk)
1100{
1101	u32 classid;
1102
1103	rcu_read_lock();  /* doing current task, which cannot vanish. */
1104	classid = task_cls_classid(current);
1105	rcu_read_unlock();
1106	if (classid && classid != sk->sk_classid)
1107		sk->sk_classid = classid;
1108}
1109EXPORT_SYMBOL(sock_update_classid);
1110#endif
1111
1112/**
1113 *	sk_alloc - All socket objects are allocated here
1114 *	@net: the applicable net namespace
1115 *	@family: protocol family
1116 *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1117 *	@prot: struct proto associated with this new sock instance
1118 */
1119struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1120		      struct proto *prot)
1121{
1122	struct sock *sk;
1123
1124	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1125	if (sk) {
1126		sk->sk_family = family;
1127		/*
1128		 * See comment in struct sock definition to understand
1129		 * why we need sk_prot_creator -acme
1130		 */
1131		sk->sk_prot = sk->sk_prot_creator = prot;
1132		sock_lock_init(sk);
1133		sock_net_set(sk, get_net(net));
1134		atomic_set(&sk->sk_wmem_alloc, 1);
1135
1136		sock_update_classid(sk);
1137	}
1138
1139	return sk;
1140}
1141EXPORT_SYMBOL(sk_alloc);
1142
1143static void __sk_free(struct sock *sk)
1144{
1145	struct sk_filter *filter;
1146
1147	if (sk->sk_destruct)
1148		sk->sk_destruct(sk);
1149
1150	filter = rcu_dereference_check(sk->sk_filter,
1151				       atomic_read(&sk->sk_wmem_alloc) == 0);
1152	if (filter) {
1153		sk_filter_uncharge(sk, filter);
1154		RCU_INIT_POINTER(sk->sk_filter, NULL);
1155	}
1156
1157	sock_disable_timestamp(sk, SOCK_TIMESTAMP);
1158	sock_disable_timestamp(sk, SOCK_TIMESTAMPING_RX_SOFTWARE);
1159
1160	if (atomic_read(&sk->sk_omem_alloc))
1161		printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n",
1162		       __func__, atomic_read(&sk->sk_omem_alloc));
1163
1164	if (sk->sk_peer_cred)
1165		put_cred(sk->sk_peer_cred);
1166	put_pid(sk->sk_peer_pid);
1167	put_net(sock_net(sk));
1168	sk_prot_free(sk->sk_prot_creator, sk);
1169}
1170
1171void sk_free(struct sock *sk)
1172{
1173	/*
1174	 * We subtract one from sk_wmem_alloc and can know if
1175	 * some packets are still in some tx queue.
1176	 * If not null, sock_wfree() will call __sk_free(sk) later
1177	 */
1178	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1179		__sk_free(sk);
1180}
1181EXPORT_SYMBOL(sk_free);
1182
1183/*
1184 * Last sock_put should drop reference to sk->sk_net. It has already
1185 * been dropped in sk_change_net. Taking reference to stopping namespace
1186 * is not an option.
1187 * Take reference to a socket to remove it from hash _alive_ and after that
1188 * destroy it in the context of init_net.
1189 */
1190void sk_release_kernel(struct sock *sk)
1191{
1192	if (sk == NULL || sk->sk_socket == NULL)
1193		return;
1194
1195	sock_hold(sk);
1196	sock_release(sk->sk_socket);
1197	release_net(sock_net(sk));
1198	sock_net_set(sk, get_net(&init_net));
1199	sock_put(sk);
1200}
1201EXPORT_SYMBOL(sk_release_kernel);
1202
1203struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
1204{
1205	struct sock *newsk;
1206
1207	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1208	if (newsk != NULL) {
1209		struct sk_filter *filter;
1210
1211		sock_copy(newsk, sk);
1212
1213		/* SANITY */
1214		get_net(sock_net(newsk));
1215		sk_node_init(&newsk->sk_node);
1216		sock_lock_init(newsk);
1217		bh_lock_sock(newsk);
1218		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1219		newsk->sk_backlog.len = 0;
1220
1221		atomic_set(&newsk->sk_rmem_alloc, 0);
1222		/*
1223		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1224		 */
1225		atomic_set(&newsk->sk_wmem_alloc, 1);
1226		atomic_set(&newsk->sk_omem_alloc, 0);
1227		skb_queue_head_init(&newsk->sk_receive_queue);
1228		skb_queue_head_init(&newsk->sk_write_queue);
1229#ifdef CONFIG_NET_DMA
1230		skb_queue_head_init(&newsk->sk_async_wait_queue);
1231#endif
1232
1233		spin_lock_init(&newsk->sk_dst_lock);
1234		rwlock_init(&newsk->sk_callback_lock);
1235		lockdep_set_class_and_name(&newsk->sk_callback_lock,
1236				af_callback_keys + newsk->sk_family,
1237				af_family_clock_key_strings[newsk->sk_family]);
1238
1239		newsk->sk_dst_cache	= NULL;
1240		newsk->sk_wmem_queued	= 0;
1241		newsk->sk_forward_alloc = 0;
1242		newsk->sk_send_head	= NULL;
1243		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1244
1245		sock_reset_flag(newsk, SOCK_DONE);
1246		skb_queue_head_init(&newsk->sk_error_queue);
1247
1248		filter = rcu_dereference_protected(newsk->sk_filter, 1);
1249		if (filter != NULL)
1250			sk_filter_charge(newsk, filter);
1251
1252		if (unlikely(xfrm_sk_clone_policy(newsk))) {
1253			/* It is still raw copy of parent, so invalidate
1254			 * destructor and make plain sk_free() */
1255			newsk->sk_destruct = NULL;
1256			bh_unlock_sock(newsk);
1257			sk_free(newsk);
1258			newsk = NULL;
1259			goto out;
1260		}
1261
1262		newsk->sk_err	   = 0;
1263		newsk->sk_priority = 0;
1264		/*
1265		 * Before updating sk_refcnt, we must commit prior changes to memory
1266		 * (Documentation/RCU/rculist_nulls.txt for details)
1267		 */
1268		smp_wmb();
1269		atomic_set(&newsk->sk_refcnt, 2);
1270
1271		/*
1272		 * Increment the counter in the same struct proto as the master
1273		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1274		 * is the same as sk->sk_prot->socks, as this field was copied
1275		 * with memcpy).
1276		 *
1277		 * This _changes_ the previous behaviour, where
1278		 * tcp_create_openreq_child always was incrementing the
1279		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1280		 * to be taken into account in all callers. -acme
1281		 */
1282		sk_refcnt_debug_inc(newsk);
1283		sk_set_socket(newsk, NULL);
1284		newsk->sk_wq = NULL;
1285
1286		if (newsk->sk_prot->sockets_allocated)
1287			percpu_counter_inc(newsk->sk_prot->sockets_allocated);
1288
1289		if (sock_flag(newsk, SOCK_TIMESTAMP) ||
1290		    sock_flag(newsk, SOCK_TIMESTAMPING_RX_SOFTWARE))
1291			net_enable_timestamp();
1292	}
1293out:
1294	return newsk;
1295}
1296EXPORT_SYMBOL_GPL(sk_clone);
1297
1298void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1299{
1300	__sk_dst_set(sk, dst);
1301	sk->sk_route_caps = dst->dev->features;
1302	if (sk->sk_route_caps & NETIF_F_GSO)
1303		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1304	sk->sk_route_caps &= ~sk->sk_route_nocaps;
1305	if (sk_can_gso(sk)) {
1306		if (dst->header_len) {
1307			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1308		} else {
1309			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1310			sk->sk_gso_max_size = dst->dev->gso_max_size;
1311		}
1312	}
1313}
1314EXPORT_SYMBOL_GPL(sk_setup_caps);
1315
1316void __init sk_init(void)
1317{
1318	if (totalram_pages <= 4096) {
1319		sysctl_wmem_max = 32767;
1320		sysctl_rmem_max = 32767;
1321		sysctl_wmem_default = 32767;
1322		sysctl_rmem_default = 32767;
1323	} else if (totalram_pages >= 131072) {
1324		sysctl_wmem_max = 131071;
1325		sysctl_rmem_max = 131071;
1326	}
1327}
1328
1329/*
1330 *	Simple resource managers for sockets.
1331 */
1332
1333
1334/*
1335 * Write buffer destructor automatically called from kfree_skb.
1336 */
1337void sock_wfree(struct sk_buff *skb)
1338{
1339	struct sock *sk = skb->sk;
1340	unsigned int len = skb->truesize;
1341
1342	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1343		/*
1344		 * Keep a reference on sk_wmem_alloc, this will be released
1345		 * after sk_write_space() call
1346		 */
1347		atomic_sub(len - 1, &sk->sk_wmem_alloc);
1348		sk->sk_write_space(sk);
1349		len = 1;
1350	}
1351	/*
1352	 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1353	 * could not do because of in-flight packets
1354	 */
1355	if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1356		__sk_free(sk);
1357}
1358EXPORT_SYMBOL(sock_wfree);
1359
1360/*
1361 * Read buffer destructor automatically called from kfree_skb.
1362 */
1363void sock_rfree(struct sk_buff *skb)
1364{
1365	struct sock *sk = skb->sk;
1366	unsigned int len = skb->truesize;
1367
1368	atomic_sub(len, &sk->sk_rmem_alloc);
1369	sk_mem_uncharge(sk, len);
1370}
1371EXPORT_SYMBOL(sock_rfree);
1372
1373
1374int sock_i_uid(struct sock *sk)
1375{
1376	int uid;
1377
1378	read_lock_bh(&sk->sk_callback_lock);
1379	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1380	read_unlock_bh(&sk->sk_callback_lock);
1381	return uid;
1382}
1383EXPORT_SYMBOL(sock_i_uid);
1384
1385unsigned long sock_i_ino(struct sock *sk)
1386{
1387	unsigned long ino;
1388
1389	read_lock_bh(&sk->sk_callback_lock);
1390	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1391	read_unlock_bh(&sk->sk_callback_lock);
1392	return ino;
1393}
1394EXPORT_SYMBOL(sock_i_ino);
1395
1396/*
1397 * Allocate a skb from the socket's send buffer.
1398 */
1399struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1400			     gfp_t priority)
1401{
1402	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1403		struct sk_buff *skb = alloc_skb(size, priority);
1404		if (skb) {
1405			skb_set_owner_w(skb, sk);
1406			return skb;
1407		}
1408	}
1409	return NULL;
1410}
1411EXPORT_SYMBOL(sock_wmalloc);
1412
1413/*
1414 * Allocate a skb from the socket's receive buffer.
1415 */
1416struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1417			     gfp_t priority)
1418{
1419	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1420		struct sk_buff *skb = alloc_skb(size, priority);
1421		if (skb) {
1422			skb_set_owner_r(skb, sk);
1423			return skb;
1424		}
1425	}
1426	return NULL;
1427}
1428
1429/*
1430 * Allocate a memory block from the socket's option memory buffer.
1431 */
1432void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1433{
1434	if ((unsigned)size <= sysctl_optmem_max &&
1435	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1436		void *mem;
1437		/* First do the add, to avoid the race if kmalloc
1438		 * might sleep.
1439		 */
1440		atomic_add(size, &sk->sk_omem_alloc);
1441		mem = kmalloc(size, priority);
1442		if (mem)
1443			return mem;
1444		atomic_sub(size, &sk->sk_omem_alloc);
1445	}
1446	return NULL;
1447}
1448EXPORT_SYMBOL(sock_kmalloc);
1449
1450/*
1451 * Free an option memory block.
1452 */
1453void sock_kfree_s(struct sock *sk, void *mem, int size)
1454{
1455	kfree(mem);
1456	atomic_sub(size, &sk->sk_omem_alloc);
1457}
1458EXPORT_SYMBOL(sock_kfree_s);
1459
1460/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1461   I think, these locks should be removed for datagram sockets.
1462 */
1463static long sock_wait_for_wmem(struct sock *sk, long timeo)
1464{
1465	DEFINE_WAIT(wait);
1466
1467	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1468	for (;;) {
1469		if (!timeo)
1470			break;
1471		if (signal_pending(current))
1472			break;
1473		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1474		prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1475		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1476			break;
1477		if (sk->sk_shutdown & SEND_SHUTDOWN)
1478			break;
1479		if (sk->sk_err)
1480			break;
1481		timeo = schedule_timeout(timeo);
1482	}
1483	finish_wait(sk_sleep(sk), &wait);
1484	return timeo;
1485}
1486
1487
1488/*
1489 *	Generic send/receive buffer handlers
1490 */
1491
1492struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1493				     unsigned long data_len, int noblock,
1494				     int *errcode)
1495{
1496	struct sk_buff *skb;
1497	gfp_t gfp_mask;
1498	long timeo;
1499	int err;
1500
1501	gfp_mask = sk->sk_allocation;
1502	if (gfp_mask & __GFP_WAIT)
1503		gfp_mask |= __GFP_REPEAT;
1504
1505	timeo = sock_sndtimeo(sk, noblock);
1506	while (1) {
1507		err = sock_error(sk);
1508		if (err != 0)
1509			goto failure;
1510
1511		err = -EPIPE;
1512		if (sk->sk_shutdown & SEND_SHUTDOWN)
1513			goto failure;
1514
1515		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1516			skb = alloc_skb(header_len, gfp_mask);
1517			if (skb) {
1518				int npages;
1519				int i;
1520
1521				/* No pages, we're done... */
1522				if (!data_len)
1523					break;
1524
1525				npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1526				skb->truesize += data_len;
1527				skb_shinfo(skb)->nr_frags = npages;
1528				for (i = 0; i < npages; i++) {
1529					struct page *page;
1530
1531					page = alloc_pages(sk->sk_allocation, 0);
1532					if (!page) {
1533						err = -ENOBUFS;
1534						skb_shinfo(skb)->nr_frags = i;
1535						kfree_skb(skb);
1536						goto failure;
1537					}
1538
1539					__skb_fill_page_desc(skb, i,
1540							page, 0,
1541							(data_len >= PAGE_SIZE ?
1542							 PAGE_SIZE :
1543							 data_len));
1544					data_len -= PAGE_SIZE;
1545				}
1546
1547				/* Full success... */
1548				break;
1549			}
1550			err = -ENOBUFS;
1551			goto failure;
1552		}
1553		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1554		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1555		err = -EAGAIN;
1556		if (!timeo)
1557			goto failure;
1558		if (signal_pending(current))
1559			goto interrupted;
1560		timeo = sock_wait_for_wmem(sk, timeo);
1561	}
1562
1563	skb_set_owner_w(skb, sk);
1564	return skb;
1565
1566interrupted:
1567	err = sock_intr_errno(timeo);
1568failure:
1569	*errcode = err;
1570	return NULL;
1571}
1572EXPORT_SYMBOL(sock_alloc_send_pskb);
1573
1574struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1575				    int noblock, int *errcode)
1576{
1577	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1578}
1579EXPORT_SYMBOL(sock_alloc_send_skb);
1580
1581static void __lock_sock(struct sock *sk)
1582	__releases(&sk->sk_lock.slock)
1583	__acquires(&sk->sk_lock.slock)
1584{
1585	DEFINE_WAIT(wait);
1586
1587	for (;;) {
1588		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1589					TASK_UNINTERRUPTIBLE);
1590		spin_unlock_bh(&sk->sk_lock.slock);
1591		schedule();
1592		spin_lock_bh(&sk->sk_lock.slock);
1593		if (!sock_owned_by_user(sk))
1594			break;
1595	}
1596	finish_wait(&sk->sk_lock.wq, &wait);
1597}
1598
1599static void __release_sock(struct sock *sk)
1600	__releases(&sk->sk_lock.slock)
1601	__acquires(&sk->sk_lock.slock)
1602{
1603	struct sk_buff *skb = sk->sk_backlog.head;
1604
1605	do {
1606		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1607		bh_unlock_sock(sk);
1608
1609		do {
1610			struct sk_buff *next = skb->next;
1611
1612			WARN_ON_ONCE(skb_dst_is_noref(skb));
1613			skb->next = NULL;
1614			sk_backlog_rcv(sk, skb);
1615
1616			/*
1617			 * We are in process context here with softirqs
1618			 * disabled, use cond_resched_softirq() to preempt.
1619			 * This is safe to do because we've taken the backlog
1620			 * queue private:
1621			 */
1622			cond_resched_softirq();
1623
1624			skb = next;
1625		} while (skb != NULL);
1626
1627		bh_lock_sock(sk);
1628	} while ((skb = sk->sk_backlog.head) != NULL);
1629
1630	/*
1631	 * Doing the zeroing here guarantee we can not loop forever
1632	 * while a wild producer attempts to flood us.
1633	 */
1634	sk->sk_backlog.len = 0;
1635}
1636
1637/**
1638 * sk_wait_data - wait for data to arrive at sk_receive_queue
1639 * @sk:    sock to wait on
1640 * @timeo: for how long
1641 *
1642 * Now socket state including sk->sk_err is changed only under lock,
1643 * hence we may omit checks after joining wait queue.
1644 * We check receive queue before schedule() only as optimization;
1645 * it is very likely that release_sock() added new data.
1646 */
1647int sk_wait_data(struct sock *sk, long *timeo)
1648{
1649	int rc;
1650	DEFINE_WAIT(wait);
1651
1652	prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1653	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1654	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1655	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1656	finish_wait(sk_sleep(sk), &wait);
1657	return rc;
1658}
1659EXPORT_SYMBOL(sk_wait_data);
1660
1661/**
1662 *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1663 *	@sk: socket
1664 *	@size: memory size to allocate
1665 *	@kind: allocation type
1666 *
1667 *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1668 *	rmem allocation. This function assumes that protocols which have
1669 *	memory_pressure use sk_wmem_queued as write buffer accounting.
1670 */
1671int __sk_mem_schedule(struct sock *sk, int size, int kind)
1672{
1673	struct proto *prot = sk->sk_prot;
1674	int amt = sk_mem_pages(size);
1675	long allocated;
1676
1677	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1678	allocated = atomic_long_add_return(amt, prot->memory_allocated);
1679
1680	/* Under limit. */
1681	if (allocated <= prot->sysctl_mem[0]) {
1682		if (prot->memory_pressure && *prot->memory_pressure)
1683			*prot->memory_pressure = 0;
1684		return 1;
1685	}
1686
1687	/* Under pressure. */
1688	if (allocated > prot->sysctl_mem[1])
1689		if (prot->enter_memory_pressure)
1690			prot->enter_memory_pressure(sk);
1691
1692	/* Over hard limit. */
1693	if (allocated > prot->sysctl_mem[2])
1694		goto suppress_allocation;
1695
1696	/* guarantee minimum buffer size under pressure */
1697	if (kind == SK_MEM_RECV) {
1698		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1699			return 1;
1700	} else { /* SK_MEM_SEND */
1701		if (sk->sk_type == SOCK_STREAM) {
1702			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1703				return 1;
1704		} else if (atomic_read(&sk->sk_wmem_alloc) <
1705			   prot->sysctl_wmem[0])
1706				return 1;
1707	}
1708
1709	if (prot->memory_pressure) {
1710		int alloc;
1711
1712		if (!*prot->memory_pressure)
1713			return 1;
1714		alloc = percpu_counter_read_positive(prot->sockets_allocated);
1715		if (prot->sysctl_mem[2] > alloc *
1716		    sk_mem_pages(sk->sk_wmem_queued +
1717				 atomic_read(&sk->sk_rmem_alloc) +
1718				 sk->sk_forward_alloc))
1719			return 1;
1720	}
1721
1722suppress_allocation:
1723
1724	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1725		sk_stream_moderate_sndbuf(sk);
1726
1727		/* Fail only if socket is _under_ its sndbuf.
1728		 * In this case we cannot block, so that we have to fail.
1729		 */
1730		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1731			return 1;
1732	}
1733
1734	trace_sock_exceed_buf_limit(sk, prot, allocated);
1735
1736	/* Alas. Undo changes. */
1737	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1738	atomic_long_sub(amt, prot->memory_allocated);
1739	return 0;
1740}
1741EXPORT_SYMBOL(__sk_mem_schedule);
1742
1743/**
1744 *	__sk_reclaim - reclaim memory_allocated
1745 *	@sk: socket
1746 */
1747void __sk_mem_reclaim(struct sock *sk)
1748{
1749	struct proto *prot = sk->sk_prot;
1750
1751	atomic_long_sub(sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT,
1752		   prot->memory_allocated);
1753	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1754
1755	if (prot->memory_pressure && *prot->memory_pressure &&
1756	    (atomic_long_read(prot->memory_allocated) < prot->sysctl_mem[0]))
1757		*prot->memory_pressure = 0;
1758}
1759EXPORT_SYMBOL(__sk_mem_reclaim);
1760
1761
1762/*
1763 * Set of default routines for initialising struct proto_ops when
1764 * the protocol does not support a particular function. In certain
1765 * cases where it makes no sense for a protocol to have a "do nothing"
1766 * function, some default processing is provided.
1767 */
1768
1769int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1770{
1771	return -EOPNOTSUPP;
1772}
1773EXPORT_SYMBOL(sock_no_bind);
1774
1775int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1776		    int len, int flags)
1777{
1778	return -EOPNOTSUPP;
1779}
1780EXPORT_SYMBOL(sock_no_connect);
1781
1782int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1783{
1784	return -EOPNOTSUPP;
1785}
1786EXPORT_SYMBOL(sock_no_socketpair);
1787
1788int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1789{
1790	return -EOPNOTSUPP;
1791}
1792EXPORT_SYMBOL(sock_no_accept);
1793
1794int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1795		    int *len, int peer)
1796{
1797	return -EOPNOTSUPP;
1798}
1799EXPORT_SYMBOL(sock_no_getname);
1800
1801unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1802{
1803	return 0;
1804}
1805EXPORT_SYMBOL(sock_no_poll);
1806
1807int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1808{
1809	return -EOPNOTSUPP;
1810}
1811EXPORT_SYMBOL(sock_no_ioctl);
1812
1813int sock_no_listen(struct socket *sock, int backlog)
1814{
1815	return -EOPNOTSUPP;
1816}
1817EXPORT_SYMBOL(sock_no_listen);
1818
1819int sock_no_shutdown(struct socket *sock, int how)
1820{
1821	return -EOPNOTSUPP;
1822}
1823EXPORT_SYMBOL(sock_no_shutdown);
1824
1825int sock_no_setsockopt(struct socket *sock, int level, int optname,
1826		    char __user *optval, unsigned int optlen)
1827{
1828	return -EOPNOTSUPP;
1829}
1830EXPORT_SYMBOL(sock_no_setsockopt);
1831
1832int sock_no_getsockopt(struct socket *sock, int level, int optname,
1833		    char __user *optval, int __user *optlen)
1834{
1835	return -EOPNOTSUPP;
1836}
1837EXPORT_SYMBOL(sock_no_getsockopt);
1838
1839int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1840		    size_t len)
1841{
1842	return -EOPNOTSUPP;
1843}
1844EXPORT_SYMBOL(sock_no_sendmsg);
1845
1846int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1847		    size_t len, int flags)
1848{
1849	return -EOPNOTSUPP;
1850}
1851EXPORT_SYMBOL(sock_no_recvmsg);
1852
1853int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1854{
1855	/* Mirror missing mmap method error code */
1856	return -ENODEV;
1857}
1858EXPORT_SYMBOL(sock_no_mmap);
1859
1860ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
1861{
1862	ssize_t res;
1863	struct msghdr msg = {.msg_flags = flags};
1864	struct kvec iov;
1865	char *kaddr = kmap(page);
1866	iov.iov_base = kaddr + offset;
1867	iov.iov_len = size;
1868	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
1869	kunmap(page);
1870	return res;
1871}
1872EXPORT_SYMBOL(sock_no_sendpage);
1873
1874/*
1875 *	Default Socket Callbacks
1876 */
1877
1878static void sock_def_wakeup(struct sock *sk)
1879{
1880	struct socket_wq *wq;
1881
1882	rcu_read_lock();
1883	wq = rcu_dereference(sk->sk_wq);
1884	if (wq_has_sleeper(wq))
1885		wake_up_interruptible_all(&wq->wait);
1886	rcu_read_unlock();
1887}
1888
1889static void sock_def_error_report(struct sock *sk)
1890{
1891	struct socket_wq *wq;
1892
1893	rcu_read_lock();
1894	wq = rcu_dereference(sk->sk_wq);
1895	if (wq_has_sleeper(wq))
1896		wake_up_interruptible_poll(&wq->wait, POLLERR);
1897	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
1898	rcu_read_unlock();
1899}
1900
1901static void sock_def_readable(struct sock *sk, int len)
1902{
1903	struct socket_wq *wq;
1904
1905	rcu_read_lock();
1906	wq = rcu_dereference(sk->sk_wq);
1907	if (wq_has_sleeper(wq))
1908		wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
1909						POLLRDNORM | POLLRDBAND);
1910	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
1911	rcu_read_unlock();
1912}
1913
1914static void sock_def_write_space(struct sock *sk)
1915{
1916	struct socket_wq *wq;
1917
1918	rcu_read_lock();
1919
1920	/* Do not wake up a writer until he can make "significant"
1921	 * progress.  --DaveM
1922	 */
1923	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
1924		wq = rcu_dereference(sk->sk_wq);
1925		if (wq_has_sleeper(wq))
1926			wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
1927						POLLWRNORM | POLLWRBAND);
1928
1929		/* Should agree with poll, otherwise some programs break */
1930		if (sock_writeable(sk))
1931			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
1932	}
1933
1934	rcu_read_unlock();
1935}
1936
1937static void sock_def_destruct(struct sock *sk)
1938{
1939	kfree(sk->sk_protinfo);
1940}
1941
1942void sk_send_sigurg(struct sock *sk)
1943{
1944	if (sk->sk_socket && sk->sk_socket->file)
1945		if (send_sigurg(&sk->sk_socket->file->f_owner))
1946			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
1947}
1948EXPORT_SYMBOL(sk_send_sigurg);
1949
1950void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1951		    unsigned long expires)
1952{
1953	if (!mod_timer(timer, expires))
1954		sock_hold(sk);
1955}
1956EXPORT_SYMBOL(sk_reset_timer);
1957
1958void sk_stop_timer(struct sock *sk, struct timer_list* timer)
1959{
1960	if (timer_pending(timer) && del_timer(timer))
1961		__sock_put(sk);
1962}
1963EXPORT_SYMBOL(sk_stop_timer);
1964
1965void sock_init_data(struct socket *sock, struct sock *sk)
1966{
1967	skb_queue_head_init(&sk->sk_receive_queue);
1968	skb_queue_head_init(&sk->sk_write_queue);
1969	skb_queue_head_init(&sk->sk_error_queue);
1970#ifdef CONFIG_NET_DMA
1971	skb_queue_head_init(&sk->sk_async_wait_queue);
1972#endif
1973
1974	sk->sk_send_head	=	NULL;
1975
1976	init_timer(&sk->sk_timer);
1977
1978	sk->sk_allocation	=	GFP_KERNEL;
1979	sk->sk_rcvbuf		=	sysctl_rmem_default;
1980	sk->sk_sndbuf		=	sysctl_wmem_default;
1981	sk->sk_state		=	TCP_CLOSE;
1982	sk_set_socket(sk, sock);
1983
1984	sock_set_flag(sk, SOCK_ZAPPED);
1985
1986	if (sock) {
1987		sk->sk_type	=	sock->type;
1988		sk->sk_wq	=	sock->wq;
1989		sock->sk	=	sk;
1990	} else
1991		sk->sk_wq	=	NULL;
1992
1993	spin_lock_init(&sk->sk_dst_lock);
1994	rwlock_init(&sk->sk_callback_lock);
1995	lockdep_set_class_and_name(&sk->sk_callback_lock,
1996			af_callback_keys + sk->sk_family,
1997			af_family_clock_key_strings[sk->sk_family]);
1998
1999	sk->sk_state_change	=	sock_def_wakeup;
2000	sk->sk_data_ready	=	sock_def_readable;
2001	sk->sk_write_space	=	sock_def_write_space;
2002	sk->sk_error_report	=	sock_def_error_report;
2003	sk->sk_destruct		=	sock_def_destruct;
2004
2005	sk->sk_sndmsg_page	=	NULL;
2006	sk->sk_sndmsg_off	=	0;
2007
2008	sk->sk_peer_pid 	=	NULL;
2009	sk->sk_peer_cred	=	NULL;
2010	sk->sk_write_pending	=	0;
2011	sk->sk_rcvlowat		=	1;
2012	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
2013	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
2014
2015	sk->sk_stamp = ktime_set(-1L, 0);
2016
2017	/*
2018	 * Before updating sk_refcnt, we must commit prior changes to memory
2019	 * (Documentation/RCU/rculist_nulls.txt for details)
2020	 */
2021	smp_wmb();
2022	atomic_set(&sk->sk_refcnt, 1);
2023	atomic_set(&sk->sk_drops, 0);
2024}
2025EXPORT_SYMBOL(sock_init_data);
2026
2027void lock_sock_nested(struct sock *sk, int subclass)
2028{
2029	might_sleep();
2030	spin_lock_bh(&sk->sk_lock.slock);
2031	if (sk->sk_lock.owned)
2032		__lock_sock(sk);
2033	sk->sk_lock.owned = 1;
2034	spin_unlock(&sk->sk_lock.slock);
2035	/*
2036	 * The sk_lock has mutex_lock() semantics here:
2037	 */
2038	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2039	local_bh_enable();
2040}
2041EXPORT_SYMBOL(lock_sock_nested);
2042
2043void release_sock(struct sock *sk)
2044{
2045	/*
2046	 * The sk_lock has mutex_unlock() semantics:
2047	 */
2048	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2049
2050	spin_lock_bh(&sk->sk_lock.slock);
2051	if (sk->sk_backlog.tail)
2052		__release_sock(sk);
2053	sk->sk_lock.owned = 0;
2054	if (waitqueue_active(&sk->sk_lock.wq))
2055		wake_up(&sk->sk_lock.wq);
2056	spin_unlock_bh(&sk->sk_lock.slock);
2057}
2058EXPORT_SYMBOL(release_sock);
2059
2060/**
2061 * lock_sock_fast - fast version of lock_sock
2062 * @sk: socket
2063 *
2064 * This version should be used for very small section, where process wont block
2065 * return false if fast path is taken
2066 *   sk_lock.slock locked, owned = 0, BH disabled
2067 * return true if slow path is taken
2068 *   sk_lock.slock unlocked, owned = 1, BH enabled
2069 */
2070bool lock_sock_fast(struct sock *sk)
2071{
2072	might_sleep();
2073	spin_lock_bh(&sk->sk_lock.slock);
2074
2075	if (!sk->sk_lock.owned)
2076		/*
2077		 * Note : We must disable BH
2078		 */
2079		return false;
2080
2081	__lock_sock(sk);
2082	sk->sk_lock.owned = 1;
2083	spin_unlock(&sk->sk_lock.slock);
2084	/*
2085	 * The sk_lock has mutex_lock() semantics here:
2086	 */
2087	mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2088	local_bh_enable();
2089	return true;
2090}
2091EXPORT_SYMBOL(lock_sock_fast);
2092
2093int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2094{
2095	struct timeval tv;
2096	if (!sock_flag(sk, SOCK_TIMESTAMP))
2097		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2098	tv = ktime_to_timeval(sk->sk_stamp);
2099	if (tv.tv_sec == -1)
2100		return -ENOENT;
2101	if (tv.tv_sec == 0) {
2102		sk->sk_stamp = ktime_get_real();
2103		tv = ktime_to_timeval(sk->sk_stamp);
2104	}
2105	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2106}
2107EXPORT_SYMBOL(sock_get_timestamp);
2108
2109int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2110{
2111	struct timespec ts;
2112	if (!sock_flag(sk, SOCK_TIMESTAMP))
2113		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2114	ts = ktime_to_timespec(sk->sk_stamp);
2115	if (ts.tv_sec == -1)
2116		return -ENOENT;
2117	if (ts.tv_sec == 0) {
2118		sk->sk_stamp = ktime_get_real();
2119		ts = ktime_to_timespec(sk->sk_stamp);
2120	}
2121	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2122}
2123EXPORT_SYMBOL(sock_get_timestampns);
2124
2125void sock_enable_timestamp(struct sock *sk, int flag)
2126{
2127	if (!sock_flag(sk, flag)) {
2128		sock_set_flag(sk, flag);
2129		/*
2130		 * we just set one of the two flags which require net
2131		 * time stamping, but time stamping might have been on
2132		 * already because of the other one
2133		 */
2134		if (!sock_flag(sk,
2135				flag == SOCK_TIMESTAMP ?
2136				SOCK_TIMESTAMPING_RX_SOFTWARE :
2137				SOCK_TIMESTAMP))
2138			net_enable_timestamp();
2139	}
2140}
2141
2142/*
2143 *	Get a socket option on an socket.
2144 *
2145 *	FIX: POSIX 1003.1g is very ambiguous here. It states that
2146 *	asynchronous errors should be reported by getsockopt. We assume
2147 *	this means if you specify SO_ERROR (otherwise whats the point of it).
2148 */
2149int sock_common_getsockopt(struct socket *sock, int level, int optname,
2150			   char __user *optval, int __user *optlen)
2151{
2152	struct sock *sk = sock->sk;
2153
2154	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2155}
2156EXPORT_SYMBOL(sock_common_getsockopt);
2157
2158#ifdef CONFIG_COMPAT
2159int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2160				  char __user *optval, int __user *optlen)
2161{
2162	struct sock *sk = sock->sk;
2163
2164	if (sk->sk_prot->compat_getsockopt != NULL)
2165		return sk->sk_prot->compat_getsockopt(sk, level, optname,
2166						      optval, optlen);
2167	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2168}
2169EXPORT_SYMBOL(compat_sock_common_getsockopt);
2170#endif
2171
2172int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2173			struct msghdr *msg, size_t size, int flags)
2174{
2175	struct sock *sk = sock->sk;
2176	int addr_len = 0;
2177	int err;
2178
2179	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2180				   flags & ~MSG_DONTWAIT, &addr_len);
2181	if (err >= 0)
2182		msg->msg_namelen = addr_len;
2183	return err;
2184}
2185EXPORT_SYMBOL(sock_common_recvmsg);
2186
2187/*
2188 *	Set socket options on an inet socket.
2189 */
2190int sock_common_setsockopt(struct socket *sock, int level, int optname,
2191			   char __user *optval, unsigned int optlen)
2192{
2193	struct sock *sk = sock->sk;
2194
2195	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2196}
2197EXPORT_SYMBOL(sock_common_setsockopt);
2198
2199#ifdef CONFIG_COMPAT
2200int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2201				  char __user *optval, unsigned int optlen)
2202{
2203	struct sock *sk = sock->sk;
2204
2205	if (sk->sk_prot->compat_setsockopt != NULL)
2206		return sk->sk_prot->compat_setsockopt(sk, level, optname,
2207						      optval, optlen);
2208	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2209}
2210EXPORT_SYMBOL(compat_sock_common_setsockopt);
2211#endif
2212
2213void sk_common_release(struct sock *sk)
2214{
2215	if (sk->sk_prot->destroy)
2216		sk->sk_prot->destroy(sk);
2217
2218	/*
2219	 * Observation: when sock_common_release is called, processes have
2220	 * no access to socket. But net still has.
2221	 * Step one, detach it from networking:
2222	 *
2223	 * A. Remove from hash tables.
2224	 */
2225
2226	sk->sk_prot->unhash(sk);
2227
2228	/*
2229	 * In this point socket cannot receive new packets, but it is possible
2230	 * that some packets are in flight because some CPU runs receiver and
2231	 * did hash table lookup before we unhashed socket. They will achieve
2232	 * receive queue and will be purged by socket destructor.
2233	 *
2234	 * Also we still have packets pending on receive queue and probably,
2235	 * our own packets waiting in device queues. sock_destroy will drain
2236	 * receive queue, but transmitted packets will delay socket destruction
2237	 * until the last reference will be released.
2238	 */
2239
2240	sock_orphan(sk);
2241
2242	xfrm_sk_free_policy(sk);
2243
2244	sk_refcnt_debug_release(sk);
2245	sock_put(sk);
2246}
2247EXPORT_SYMBOL(sk_common_release);
2248
2249static DEFINE_RWLOCK(proto_list_lock);
2250static LIST_HEAD(proto_list);
2251
2252#ifdef CONFIG_PROC_FS
2253#define PROTO_INUSE_NR	64	/* should be enough for the first time */
2254struct prot_inuse {
2255	int val[PROTO_INUSE_NR];
2256};
2257
2258static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2259
2260#ifdef CONFIG_NET_NS
2261void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2262{
2263	__this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2264}
2265EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2266
2267int sock_prot_inuse_get(struct net *net, struct proto *prot)
2268{
2269	int cpu, idx = prot->inuse_idx;
2270	int res = 0;
2271
2272	for_each_possible_cpu(cpu)
2273		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2274
2275	return res >= 0 ? res : 0;
2276}
2277EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2278
2279static int __net_init sock_inuse_init_net(struct net *net)
2280{
2281	net->core.inuse = alloc_percpu(struct prot_inuse);
2282	return net->core.inuse ? 0 : -ENOMEM;
2283}
2284
2285static void __net_exit sock_inuse_exit_net(struct net *net)
2286{
2287	free_percpu(net->core.inuse);
2288}
2289
2290static struct pernet_operations net_inuse_ops = {
2291	.init = sock_inuse_init_net,
2292	.exit = sock_inuse_exit_net,
2293};
2294
2295static __init int net_inuse_init(void)
2296{
2297	if (register_pernet_subsys(&net_inuse_ops))
2298		panic("Cannot initialize net inuse counters");
2299
2300	return 0;
2301}
2302
2303core_initcall(net_inuse_init);
2304#else
2305static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2306
2307void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2308{
2309	__this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2310}
2311EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2312
2313int sock_prot_inuse_get(struct net *net, struct proto *prot)
2314{
2315	int cpu, idx = prot->inuse_idx;
2316	int res = 0;
2317
2318	for_each_possible_cpu(cpu)
2319		res += per_cpu(prot_inuse, cpu).val[idx];
2320
2321	return res >= 0 ? res : 0;
2322}
2323EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2324#endif
2325
2326static void assign_proto_idx(struct proto *prot)
2327{
2328	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2329
2330	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2331		printk(KERN_ERR "PROTO_INUSE_NR exhausted\n");
2332		return;
2333	}
2334
2335	set_bit(prot->inuse_idx, proto_inuse_idx);
2336}
2337
2338static void release_proto_idx(struct proto *prot)
2339{
2340	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2341		clear_bit(prot->inuse_idx, proto_inuse_idx);
2342}
2343#else
2344static inline void assign_proto_idx(struct proto *prot)
2345{
2346}
2347
2348static inline void release_proto_idx(struct proto *prot)
2349{
2350}
2351#endif
2352
2353int proto_register(struct proto *prot, int alloc_slab)
2354{
2355	if (alloc_slab) {
2356		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2357					SLAB_HWCACHE_ALIGN | prot->slab_flags,
2358					NULL);
2359
2360		if (prot->slab == NULL) {
2361			printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n",
2362			       prot->name);
2363			goto out;
2364		}
2365
2366		if (prot->rsk_prot != NULL) {
2367			prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2368			if (prot->rsk_prot->slab_name == NULL)
2369				goto out_free_sock_slab;
2370
2371			prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2372								 prot->rsk_prot->obj_size, 0,
2373								 SLAB_HWCACHE_ALIGN, NULL);
2374
2375			if (prot->rsk_prot->slab == NULL) {
2376				printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n",
2377				       prot->name);
2378				goto out_free_request_sock_slab_name;
2379			}
2380		}
2381
2382		if (prot->twsk_prot != NULL) {
2383			prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2384
2385			if (prot->twsk_prot->twsk_slab_name == NULL)
2386				goto out_free_request_sock_slab;
2387
2388			prot->twsk_prot->twsk_slab =
2389				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2390						  prot->twsk_prot->twsk_obj_size,
2391						  0,
2392						  SLAB_HWCACHE_ALIGN |
2393							prot->slab_flags,
2394						  NULL);
2395			if (prot->twsk_prot->twsk_slab == NULL)
2396				goto out_free_timewait_sock_slab_name;
2397		}
2398	}
2399
2400	write_lock(&proto_list_lock);
2401	list_add(&prot->node, &proto_list);
2402	assign_proto_idx(prot);
2403	write_unlock(&proto_list_lock);
2404	return 0;
2405
2406out_free_timewait_sock_slab_name:
2407	kfree(prot->twsk_prot->twsk_slab_name);
2408out_free_request_sock_slab:
2409	if (prot->rsk_prot && prot->rsk_prot->slab) {
2410		kmem_cache_destroy(prot->rsk_prot->slab);
2411		prot->rsk_prot->slab = NULL;
2412	}
2413out_free_request_sock_slab_name:
2414	if (prot->rsk_prot)
2415		kfree(prot->rsk_prot->slab_name);
2416out_free_sock_slab:
2417	kmem_cache_destroy(prot->slab);
2418	prot->slab = NULL;
2419out:
2420	return -ENOBUFS;
2421}
2422EXPORT_SYMBOL(proto_register);
2423
2424void proto_unregister(struct proto *prot)
2425{
2426	write_lock(&proto_list_lock);
2427	release_proto_idx(prot);
2428	list_del(&prot->node);
2429	write_unlock(&proto_list_lock);
2430
2431	if (prot->slab != NULL) {
2432		kmem_cache_destroy(prot->slab);
2433		prot->slab = NULL;
2434	}
2435
2436	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2437		kmem_cache_destroy(prot->rsk_prot->slab);
2438		kfree(prot->rsk_prot->slab_name);
2439		prot->rsk_prot->slab = NULL;
2440	}
2441
2442	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2443		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2444		kfree(prot->twsk_prot->twsk_slab_name);
2445		prot->twsk_prot->twsk_slab = NULL;
2446	}
2447}
2448EXPORT_SYMBOL(proto_unregister);
2449
2450#ifdef CONFIG_PROC_FS
2451static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2452	__acquires(proto_list_lock)
2453{
2454	read_lock(&proto_list_lock);
2455	return seq_list_start_head(&proto_list, *pos);
2456}
2457
2458static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2459{
2460	return seq_list_next(v, &proto_list, pos);
2461}
2462
2463static void proto_seq_stop(struct seq_file *seq, void *v)
2464	__releases(proto_list_lock)
2465{
2466	read_unlock(&proto_list_lock);
2467}
2468
2469static char proto_method_implemented(const void *method)
2470{
2471	return method == NULL ? 'n' : 'y';
2472}
2473
2474static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2475{
2476	seq_printf(seq, "%-9s %4u %6d  %6ld   %-3s %6u   %-3s  %-10s "
2477			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2478		   proto->name,
2479		   proto->obj_size,
2480		   sock_prot_inuse_get(seq_file_net(seq), proto),
2481		   proto->memory_allocated != NULL ? atomic_long_read(proto->memory_allocated) : -1L,
2482		   proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI",
2483		   proto->max_header,
2484		   proto->slab == NULL ? "no" : "yes",
2485		   module_name(proto->owner),
2486		   proto_method_implemented(proto->close),
2487		   proto_method_implemented(proto->connect),
2488		   proto_method_implemented(proto->disconnect),
2489		   proto_method_implemented(proto->accept),
2490		   proto_method_implemented(proto->ioctl),
2491		   proto_method_implemented(proto->init),
2492		   proto_method_implemented(proto->destroy),
2493		   proto_method_implemented(proto->shutdown),
2494		   proto_method_implemented(proto->setsockopt),
2495		   proto_method_implemented(proto->getsockopt),
2496		   proto_method_implemented(proto->sendmsg),
2497		   proto_method_implemented(proto->recvmsg),
2498		   proto_method_implemented(proto->sendpage),
2499		   proto_method_implemented(proto->bind),
2500		   proto_method_implemented(proto->backlog_rcv),
2501		   proto_method_implemented(proto->hash),
2502		   proto_method_implemented(proto->unhash),
2503		   proto_method_implemented(proto->get_port),
2504		   proto_method_implemented(proto->enter_memory_pressure));
2505}
2506
2507static int proto_seq_show(struct seq_file *seq, void *v)
2508{
2509	if (v == &proto_list)
2510		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2511			   "protocol",
2512			   "size",
2513			   "sockets",
2514			   "memory",
2515			   "press",
2516			   "maxhdr",
2517			   "slab",
2518			   "module",
2519			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2520	else
2521		proto_seq_printf(seq, list_entry(v, struct proto, node));
2522	return 0;
2523}
2524
2525static const struct seq_operations proto_seq_ops = {
2526	.start  = proto_seq_start,
2527	.next   = proto_seq_next,
2528	.stop   = proto_seq_stop,
2529	.show   = proto_seq_show,
2530};
2531
2532static int proto_seq_open(struct inode *inode, struct file *file)
2533{
2534	return seq_open_net(inode, file, &proto_seq_ops,
2535			    sizeof(struct seq_net_private));
2536}
2537
2538static const struct file_operations proto_seq_fops = {
2539	.owner		= THIS_MODULE,
2540	.open		= proto_seq_open,
2541	.read		= seq_read,
2542	.llseek		= seq_lseek,
2543	.release	= seq_release_net,
2544};
2545
2546static __net_init int proto_init_net(struct net *net)
2547{
2548	if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2549		return -ENOMEM;
2550
2551	return 0;
2552}
2553
2554static __net_exit void proto_exit_net(struct net *net)
2555{
2556	proc_net_remove(net, "protocols");
2557}
2558
2559
2560static __net_initdata struct pernet_operations proto_net_ops = {
2561	.init = proto_init_net,
2562	.exit = proto_exit_net,
2563};
2564
2565static int __init proto_init(void)
2566{
2567	return register_pernet_subsys(&proto_net_ops);
2568}
2569
2570subsys_initcall(proto_init);
2571
2572#endif /* PROC_FS */
2573