xref: /linux/net/core/sock.c (revision e27ecdd94d81e5bc3d1f68591701db5adb342f0d)
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 
114 #include <asm/uaccess.h>
115 #include <asm/system.h>
116 
117 #include <linux/netdevice.h>
118 #include <net/protocol.h>
119 #include <linux/skbuff.h>
120 #include <net/net_namespace.h>
121 #include <net/request_sock.h>
122 #include <net/sock.h>
123 #include <linux/net_tstamp.h>
124 #include <net/xfrm.h>
125 #include <linux/ipsec.h>
126 
127 #include <linux/filter.h>
128 
129 #ifdef CONFIG_INET
130 #include <net/tcp.h>
131 #endif
132 
133 /*
134  * Each address family might have different locking rules, so we have
135  * one slock key per address family:
136  */
137 static struct lock_class_key af_family_keys[AF_MAX];
138 static struct lock_class_key af_family_slock_keys[AF_MAX];
139 
140 /*
141  * Make lock validator output more readable. (we pre-construct these
142  * strings build-time, so that runtime initialization of socket
143  * locks is fast):
144  */
145 static const char *af_family_key_strings[AF_MAX+1] = {
146   "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX"     , "sk_lock-AF_INET"     ,
147   "sk_lock-AF_AX25"  , "sk_lock-AF_IPX"      , "sk_lock-AF_APPLETALK",
148   "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE"   , "sk_lock-AF_ATMPVC"   ,
149   "sk_lock-AF_X25"   , "sk_lock-AF_INET6"    , "sk_lock-AF_ROSE"     ,
150   "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI"  , "sk_lock-AF_SECURITY" ,
151   "sk_lock-AF_KEY"   , "sk_lock-AF_NETLINK"  , "sk_lock-AF_PACKET"   ,
152   "sk_lock-AF_ASH"   , "sk_lock-AF_ECONET"   , "sk_lock-AF_ATMSVC"   ,
153   "sk_lock-AF_RDS"   , "sk_lock-AF_SNA"      , "sk_lock-AF_IRDA"     ,
154   "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE"  , "sk_lock-AF_LLC"      ,
155   "sk_lock-27"       , "sk_lock-28"          , "sk_lock-AF_CAN"      ,
156   "sk_lock-AF_TIPC"  , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV"        ,
157   "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN"     , "sk_lock-AF_PHONET"   ,
158   "sk_lock-AF_IEEE802154",
159   "sk_lock-AF_MAX"
160 };
161 static const char *af_family_slock_key_strings[AF_MAX+1] = {
162   "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
163   "slock-AF_AX25"  , "slock-AF_IPX"      , "slock-AF_APPLETALK",
164   "slock-AF_NETROM", "slock-AF_BRIDGE"   , "slock-AF_ATMPVC"   ,
165   "slock-AF_X25"   , "slock-AF_INET6"    , "slock-AF_ROSE"     ,
166   "slock-AF_DECnet", "slock-AF_NETBEUI"  , "slock-AF_SECURITY" ,
167   "slock-AF_KEY"   , "slock-AF_NETLINK"  , "slock-AF_PACKET"   ,
168   "slock-AF_ASH"   , "slock-AF_ECONET"   , "slock-AF_ATMSVC"   ,
169   "slock-AF_RDS"   , "slock-AF_SNA"      , "slock-AF_IRDA"     ,
170   "slock-AF_PPPOX" , "slock-AF_WANPIPE"  , "slock-AF_LLC"      ,
171   "slock-27"       , "slock-28"          , "slock-AF_CAN"      ,
172   "slock-AF_TIPC"  , "slock-AF_BLUETOOTH", "slock-AF_IUCV"     ,
173   "slock-AF_RXRPC" , "slock-AF_ISDN"     , "slock-AF_PHONET"   ,
174   "slock-AF_IEEE802154",
175   "slock-AF_MAX"
176 };
177 static const char *af_family_clock_key_strings[AF_MAX+1] = {
178   "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
179   "clock-AF_AX25"  , "clock-AF_IPX"      , "clock-AF_APPLETALK",
180   "clock-AF_NETROM", "clock-AF_BRIDGE"   , "clock-AF_ATMPVC"   ,
181   "clock-AF_X25"   , "clock-AF_INET6"    , "clock-AF_ROSE"     ,
182   "clock-AF_DECnet", "clock-AF_NETBEUI"  , "clock-AF_SECURITY" ,
183   "clock-AF_KEY"   , "clock-AF_NETLINK"  , "clock-AF_PACKET"   ,
184   "clock-AF_ASH"   , "clock-AF_ECONET"   , "clock-AF_ATMSVC"   ,
185   "clock-AF_RDS"   , "clock-AF_SNA"      , "clock-AF_IRDA"     ,
186   "clock-AF_PPPOX" , "clock-AF_WANPIPE"  , "clock-AF_LLC"      ,
187   "clock-27"       , "clock-28"          , "clock-AF_CAN"      ,
188   "clock-AF_TIPC"  , "clock-AF_BLUETOOTH", "clock-AF_IUCV"     ,
189   "clock-AF_RXRPC" , "clock-AF_ISDN"     , "clock-AF_PHONET"   ,
190   "clock-AF_IEEE802154",
191   "clock-AF_MAX"
192 };
193 
194 /*
195  * sk_callback_lock locking rules are per-address-family,
196  * so split the lock classes by using a per-AF key:
197  */
198 static struct lock_class_key af_callback_keys[AF_MAX];
199 
200 /* Take into consideration the size of the struct sk_buff overhead in the
201  * determination of these values, since that is non-constant across
202  * platforms.  This makes socket queueing behavior and performance
203  * not depend upon such differences.
204  */
205 #define _SK_MEM_PACKETS		256
206 #define _SK_MEM_OVERHEAD	(sizeof(struct sk_buff) + 256)
207 #define SK_WMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
208 #define SK_RMEM_MAX		(_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
209 
210 /* Run time adjustable parameters. */
211 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
212 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
213 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
214 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
215 
216 /* Maximal space eaten by iovec or ancilliary data plus some space */
217 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
218 EXPORT_SYMBOL(sysctl_optmem_max);
219 
220 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
221 {
222 	struct timeval tv;
223 
224 	if (optlen < sizeof(tv))
225 		return -EINVAL;
226 	if (copy_from_user(&tv, optval, sizeof(tv)))
227 		return -EFAULT;
228 	if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
229 		return -EDOM;
230 
231 	if (tv.tv_sec < 0) {
232 		static int warned __read_mostly;
233 
234 		*timeo_p = 0;
235 		if (warned < 10 && net_ratelimit()) {
236 			warned++;
237 			printk(KERN_INFO "sock_set_timeout: `%s' (pid %d) "
238 			       "tries to set negative timeout\n",
239 				current->comm, task_pid_nr(current));
240 		}
241 		return 0;
242 	}
243 	*timeo_p = MAX_SCHEDULE_TIMEOUT;
244 	if (tv.tv_sec == 0 && tv.tv_usec == 0)
245 		return 0;
246 	if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
247 		*timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
248 	return 0;
249 }
250 
251 static void sock_warn_obsolete_bsdism(const char *name)
252 {
253 	static int warned;
254 	static char warncomm[TASK_COMM_LEN];
255 	if (strcmp(warncomm, current->comm) && warned < 5) {
256 		strcpy(warncomm,  current->comm);
257 		printk(KERN_WARNING "process `%s' is using obsolete "
258 		       "%s SO_BSDCOMPAT\n", warncomm, name);
259 		warned++;
260 	}
261 }
262 
263 static void sock_disable_timestamp(struct sock *sk, int flag)
264 {
265 	if (sock_flag(sk, flag)) {
266 		sock_reset_flag(sk, flag);
267 		if (!sock_flag(sk, SOCK_TIMESTAMP) &&
268 		    !sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE)) {
269 			net_disable_timestamp();
270 		}
271 	}
272 }
273 
274 
275 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
276 {
277 	int err = 0;
278 	int skb_len;
279 
280 	/* Cast sk->rcvbuf to unsigned... It's pointless, but reduces
281 	   number of warnings when compiling with -W --ANK
282 	 */
283 	if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
284 	    (unsigned)sk->sk_rcvbuf) {
285 		err = -ENOMEM;
286 		goto out;
287 	}
288 
289 	err = sk_filter(sk, skb);
290 	if (err)
291 		goto out;
292 
293 	if (!sk_rmem_schedule(sk, skb->truesize)) {
294 		err = -ENOBUFS;
295 		goto out;
296 	}
297 
298 	skb->dev = NULL;
299 	skb_set_owner_r(skb, sk);
300 
301 	/* Cache the SKB length before we tack it onto the receive
302 	 * queue.  Once it is added it no longer belongs to us and
303 	 * may be freed by other threads of control pulling packets
304 	 * from the queue.
305 	 */
306 	skb_len = skb->len;
307 
308 	skb_queue_tail(&sk->sk_receive_queue, skb);
309 
310 	if (!sock_flag(sk, SOCK_DEAD))
311 		sk->sk_data_ready(sk, skb_len);
312 out:
313 	return err;
314 }
315 EXPORT_SYMBOL(sock_queue_rcv_skb);
316 
317 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
318 {
319 	int rc = NET_RX_SUCCESS;
320 
321 	if (sk_filter(sk, skb))
322 		goto discard_and_relse;
323 
324 	skb->dev = NULL;
325 
326 	if (nested)
327 		bh_lock_sock_nested(sk);
328 	else
329 		bh_lock_sock(sk);
330 	if (!sock_owned_by_user(sk)) {
331 		/*
332 		 * trylock + unlock semantics:
333 		 */
334 		mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
335 
336 		rc = sk_backlog_rcv(sk, skb);
337 
338 		mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
339 	} else
340 		sk_add_backlog(sk, skb);
341 	bh_unlock_sock(sk);
342 out:
343 	sock_put(sk);
344 	return rc;
345 discard_and_relse:
346 	kfree_skb(skb);
347 	goto out;
348 }
349 EXPORT_SYMBOL(sk_receive_skb);
350 
351 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
352 {
353 	struct dst_entry *dst = sk->sk_dst_cache;
354 
355 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
356 		sk->sk_dst_cache = NULL;
357 		dst_release(dst);
358 		return NULL;
359 	}
360 
361 	return dst;
362 }
363 EXPORT_SYMBOL(__sk_dst_check);
364 
365 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
366 {
367 	struct dst_entry *dst = sk_dst_get(sk);
368 
369 	if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
370 		sk_dst_reset(sk);
371 		dst_release(dst);
372 		return NULL;
373 	}
374 
375 	return dst;
376 }
377 EXPORT_SYMBOL(sk_dst_check);
378 
379 static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
380 {
381 	int ret = -ENOPROTOOPT;
382 #ifdef CONFIG_NETDEVICES
383 	struct net *net = sock_net(sk);
384 	char devname[IFNAMSIZ];
385 	int index;
386 
387 	/* Sorry... */
388 	ret = -EPERM;
389 	if (!capable(CAP_NET_RAW))
390 		goto out;
391 
392 	ret = -EINVAL;
393 	if (optlen < 0)
394 		goto out;
395 
396 	/* Bind this socket to a particular device like "eth0",
397 	 * as specified in the passed interface name. If the
398 	 * name is "" or the option length is zero the socket
399 	 * is not bound.
400 	 */
401 	if (optlen > IFNAMSIZ - 1)
402 		optlen = IFNAMSIZ - 1;
403 	memset(devname, 0, sizeof(devname));
404 
405 	ret = -EFAULT;
406 	if (copy_from_user(devname, optval, optlen))
407 		goto out;
408 
409 	if (devname[0] == '\0') {
410 		index = 0;
411 	} else {
412 		struct net_device *dev = dev_get_by_name(net, devname);
413 
414 		ret = -ENODEV;
415 		if (!dev)
416 			goto out;
417 
418 		index = dev->ifindex;
419 		dev_put(dev);
420 	}
421 
422 	lock_sock(sk);
423 	sk->sk_bound_dev_if = index;
424 	sk_dst_reset(sk);
425 	release_sock(sk);
426 
427 	ret = 0;
428 
429 out:
430 #endif
431 
432 	return ret;
433 }
434 
435 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
436 {
437 	if (valbool)
438 		sock_set_flag(sk, bit);
439 	else
440 		sock_reset_flag(sk, bit);
441 }
442 
443 /*
444  *	This is meant for all protocols to use and covers goings on
445  *	at the socket level. Everything here is generic.
446  */
447 
448 int sock_setsockopt(struct socket *sock, int level, int optname,
449 		    char __user *optval, int optlen)
450 {
451 	struct sock *sk = sock->sk;
452 	int val;
453 	int valbool;
454 	struct linger ling;
455 	int ret = 0;
456 
457 	/*
458 	 *	Options without arguments
459 	 */
460 
461 	if (optname == SO_BINDTODEVICE)
462 		return sock_bindtodevice(sk, optval, optlen);
463 
464 	if (optlen < sizeof(int))
465 		return -EINVAL;
466 
467 	if (get_user(val, (int __user *)optval))
468 		return -EFAULT;
469 
470 	valbool = val ? 1 : 0;
471 
472 	lock_sock(sk);
473 
474 	switch (optname) {
475 	case SO_DEBUG:
476 		if (val && !capable(CAP_NET_ADMIN))
477 			ret = -EACCES;
478 		else
479 			sock_valbool_flag(sk, SOCK_DBG, valbool);
480 		break;
481 	case SO_REUSEADDR:
482 		sk->sk_reuse = valbool;
483 		break;
484 	case SO_TYPE:
485 	case SO_ERROR:
486 		ret = -ENOPROTOOPT;
487 		break;
488 	case SO_DONTROUTE:
489 		sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
490 		break;
491 	case SO_BROADCAST:
492 		sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
493 		break;
494 	case SO_SNDBUF:
495 		/* Don't error on this BSD doesn't and if you think
496 		   about it this is right. Otherwise apps have to
497 		   play 'guess the biggest size' games. RCVBUF/SNDBUF
498 		   are treated in BSD as hints */
499 
500 		if (val > sysctl_wmem_max)
501 			val = sysctl_wmem_max;
502 set_sndbuf:
503 		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
504 		if ((val * 2) < SOCK_MIN_SNDBUF)
505 			sk->sk_sndbuf = SOCK_MIN_SNDBUF;
506 		else
507 			sk->sk_sndbuf = val * 2;
508 
509 		/*
510 		 *	Wake up sending tasks if we
511 		 *	upped the value.
512 		 */
513 		sk->sk_write_space(sk);
514 		break;
515 
516 	case SO_SNDBUFFORCE:
517 		if (!capable(CAP_NET_ADMIN)) {
518 			ret = -EPERM;
519 			break;
520 		}
521 		goto set_sndbuf;
522 
523 	case SO_RCVBUF:
524 		/* Don't error on this BSD doesn't and if you think
525 		   about it this is right. Otherwise apps have to
526 		   play 'guess the biggest size' games. RCVBUF/SNDBUF
527 		   are treated in BSD as hints */
528 
529 		if (val > sysctl_rmem_max)
530 			val = sysctl_rmem_max;
531 set_rcvbuf:
532 		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
533 		/*
534 		 * We double it on the way in to account for
535 		 * "struct sk_buff" etc. overhead.   Applications
536 		 * assume that the SO_RCVBUF setting they make will
537 		 * allow that much actual data to be received on that
538 		 * socket.
539 		 *
540 		 * Applications are unaware that "struct sk_buff" and
541 		 * other overheads allocate from the receive buffer
542 		 * during socket buffer allocation.
543 		 *
544 		 * And after considering the possible alternatives,
545 		 * returning the value we actually used in getsockopt
546 		 * is the most desirable behavior.
547 		 */
548 		if ((val * 2) < SOCK_MIN_RCVBUF)
549 			sk->sk_rcvbuf = SOCK_MIN_RCVBUF;
550 		else
551 			sk->sk_rcvbuf = val * 2;
552 		break;
553 
554 	case SO_RCVBUFFORCE:
555 		if (!capable(CAP_NET_ADMIN)) {
556 			ret = -EPERM;
557 			break;
558 		}
559 		goto set_rcvbuf;
560 
561 	case SO_KEEPALIVE:
562 #ifdef CONFIG_INET
563 		if (sk->sk_protocol == IPPROTO_TCP)
564 			tcp_set_keepalive(sk, valbool);
565 #endif
566 		sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
567 		break;
568 
569 	case SO_OOBINLINE:
570 		sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
571 		break;
572 
573 	case SO_NO_CHECK:
574 		sk->sk_no_check = valbool;
575 		break;
576 
577 	case SO_PRIORITY:
578 		if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
579 			sk->sk_priority = val;
580 		else
581 			ret = -EPERM;
582 		break;
583 
584 	case SO_LINGER:
585 		if (optlen < sizeof(ling)) {
586 			ret = -EINVAL;	/* 1003.1g */
587 			break;
588 		}
589 		if (copy_from_user(&ling, optval, sizeof(ling))) {
590 			ret = -EFAULT;
591 			break;
592 		}
593 		if (!ling.l_onoff)
594 			sock_reset_flag(sk, SOCK_LINGER);
595 		else {
596 #if (BITS_PER_LONG == 32)
597 			if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
598 				sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
599 			else
600 #endif
601 				sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
602 			sock_set_flag(sk, SOCK_LINGER);
603 		}
604 		break;
605 
606 	case SO_BSDCOMPAT:
607 		sock_warn_obsolete_bsdism("setsockopt");
608 		break;
609 
610 	case SO_PASSCRED:
611 		if (valbool)
612 			set_bit(SOCK_PASSCRED, &sock->flags);
613 		else
614 			clear_bit(SOCK_PASSCRED, &sock->flags);
615 		break;
616 
617 	case SO_TIMESTAMP:
618 	case SO_TIMESTAMPNS:
619 		if (valbool)  {
620 			if (optname == SO_TIMESTAMP)
621 				sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
622 			else
623 				sock_set_flag(sk, SOCK_RCVTSTAMPNS);
624 			sock_set_flag(sk, SOCK_RCVTSTAMP);
625 			sock_enable_timestamp(sk, SOCK_TIMESTAMP);
626 		} else {
627 			sock_reset_flag(sk, SOCK_RCVTSTAMP);
628 			sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
629 		}
630 		break;
631 
632 	case SO_TIMESTAMPING:
633 		if (val & ~SOF_TIMESTAMPING_MASK) {
634 			ret = EINVAL;
635 			break;
636 		}
637 		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE,
638 				  val & SOF_TIMESTAMPING_TX_HARDWARE);
639 		sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE,
640 				  val & SOF_TIMESTAMPING_TX_SOFTWARE);
641 		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE,
642 				  val & SOF_TIMESTAMPING_RX_HARDWARE);
643 		if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
644 			sock_enable_timestamp(sk,
645 					      SOCK_TIMESTAMPING_RX_SOFTWARE);
646 		else
647 			sock_disable_timestamp(sk,
648 					       SOCK_TIMESTAMPING_RX_SOFTWARE);
649 		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE,
650 				  val & SOF_TIMESTAMPING_SOFTWARE);
651 		sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE,
652 				  val & SOF_TIMESTAMPING_SYS_HARDWARE);
653 		sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE,
654 				  val & SOF_TIMESTAMPING_RAW_HARDWARE);
655 		break;
656 
657 	case SO_RCVLOWAT:
658 		if (val < 0)
659 			val = INT_MAX;
660 		sk->sk_rcvlowat = val ? : 1;
661 		break;
662 
663 	case SO_RCVTIMEO:
664 		ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
665 		break;
666 
667 	case SO_SNDTIMEO:
668 		ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
669 		break;
670 
671 	case SO_ATTACH_FILTER:
672 		ret = -EINVAL;
673 		if (optlen == sizeof(struct sock_fprog)) {
674 			struct sock_fprog fprog;
675 
676 			ret = -EFAULT;
677 			if (copy_from_user(&fprog, optval, sizeof(fprog)))
678 				break;
679 
680 			ret = sk_attach_filter(&fprog, sk);
681 		}
682 		break;
683 
684 	case SO_DETACH_FILTER:
685 		ret = sk_detach_filter(sk);
686 		break;
687 
688 	case SO_PASSSEC:
689 		if (valbool)
690 			set_bit(SOCK_PASSSEC, &sock->flags);
691 		else
692 			clear_bit(SOCK_PASSSEC, &sock->flags);
693 		break;
694 	case SO_MARK:
695 		if (!capable(CAP_NET_ADMIN))
696 			ret = -EPERM;
697 		else
698 			sk->sk_mark = val;
699 		break;
700 
701 		/* We implement the SO_SNDLOWAT etc to
702 		   not be settable (1003.1g 5.3) */
703 	default:
704 		ret = -ENOPROTOOPT;
705 		break;
706 	}
707 	release_sock(sk);
708 	return ret;
709 }
710 EXPORT_SYMBOL(sock_setsockopt);
711 
712 
713 int sock_getsockopt(struct socket *sock, int level, int optname,
714 		    char __user *optval, int __user *optlen)
715 {
716 	struct sock *sk = sock->sk;
717 
718 	union {
719 		int val;
720 		struct linger ling;
721 		struct timeval tm;
722 	} v;
723 
724 	unsigned int lv = sizeof(int);
725 	int len;
726 
727 	if (get_user(len, optlen))
728 		return -EFAULT;
729 	if (len < 0)
730 		return -EINVAL;
731 
732 	memset(&v, 0, sizeof(v));
733 
734 	switch (optname) {
735 	case SO_DEBUG:
736 		v.val = sock_flag(sk, SOCK_DBG);
737 		break;
738 
739 	case SO_DONTROUTE:
740 		v.val = sock_flag(sk, SOCK_LOCALROUTE);
741 		break;
742 
743 	case SO_BROADCAST:
744 		v.val = !!sock_flag(sk, SOCK_BROADCAST);
745 		break;
746 
747 	case SO_SNDBUF:
748 		v.val = sk->sk_sndbuf;
749 		break;
750 
751 	case SO_RCVBUF:
752 		v.val = sk->sk_rcvbuf;
753 		break;
754 
755 	case SO_REUSEADDR:
756 		v.val = sk->sk_reuse;
757 		break;
758 
759 	case SO_KEEPALIVE:
760 		v.val = !!sock_flag(sk, SOCK_KEEPOPEN);
761 		break;
762 
763 	case SO_TYPE:
764 		v.val = sk->sk_type;
765 		break;
766 
767 	case SO_ERROR:
768 		v.val = -sock_error(sk);
769 		if (v.val == 0)
770 			v.val = xchg(&sk->sk_err_soft, 0);
771 		break;
772 
773 	case SO_OOBINLINE:
774 		v.val = !!sock_flag(sk, SOCK_URGINLINE);
775 		break;
776 
777 	case SO_NO_CHECK:
778 		v.val = sk->sk_no_check;
779 		break;
780 
781 	case SO_PRIORITY:
782 		v.val = sk->sk_priority;
783 		break;
784 
785 	case SO_LINGER:
786 		lv		= sizeof(v.ling);
787 		v.ling.l_onoff	= !!sock_flag(sk, SOCK_LINGER);
788 		v.ling.l_linger	= sk->sk_lingertime / HZ;
789 		break;
790 
791 	case SO_BSDCOMPAT:
792 		sock_warn_obsolete_bsdism("getsockopt");
793 		break;
794 
795 	case SO_TIMESTAMP:
796 		v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
797 				!sock_flag(sk, SOCK_RCVTSTAMPNS);
798 		break;
799 
800 	case SO_TIMESTAMPNS:
801 		v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
802 		break;
803 
804 	case SO_TIMESTAMPING:
805 		v.val = 0;
806 		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
807 			v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
808 		if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
809 			v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
810 		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
811 			v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
812 		if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
813 			v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
814 		if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
815 			v.val |= SOF_TIMESTAMPING_SOFTWARE;
816 		if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
817 			v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
818 		if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
819 			v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
820 		break;
821 
822 	case SO_RCVTIMEO:
823 		lv = sizeof(struct timeval);
824 		if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
825 			v.tm.tv_sec = 0;
826 			v.tm.tv_usec = 0;
827 		} else {
828 			v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
829 			v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
830 		}
831 		break;
832 
833 	case SO_SNDTIMEO:
834 		lv = sizeof(struct timeval);
835 		if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
836 			v.tm.tv_sec = 0;
837 			v.tm.tv_usec = 0;
838 		} else {
839 			v.tm.tv_sec = sk->sk_sndtimeo / HZ;
840 			v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
841 		}
842 		break;
843 
844 	case SO_RCVLOWAT:
845 		v.val = sk->sk_rcvlowat;
846 		break;
847 
848 	case SO_SNDLOWAT:
849 		v.val = 1;
850 		break;
851 
852 	case SO_PASSCRED:
853 		v.val = test_bit(SOCK_PASSCRED, &sock->flags) ? 1 : 0;
854 		break;
855 
856 	case SO_PEERCRED:
857 		if (len > sizeof(sk->sk_peercred))
858 			len = sizeof(sk->sk_peercred);
859 		if (copy_to_user(optval, &sk->sk_peercred, len))
860 			return -EFAULT;
861 		goto lenout;
862 
863 	case SO_PEERNAME:
864 	{
865 		char address[128];
866 
867 		if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
868 			return -ENOTCONN;
869 		if (lv < len)
870 			return -EINVAL;
871 		if (copy_to_user(optval, address, len))
872 			return -EFAULT;
873 		goto lenout;
874 	}
875 
876 	/* Dubious BSD thing... Probably nobody even uses it, but
877 	 * the UNIX standard wants it for whatever reason... -DaveM
878 	 */
879 	case SO_ACCEPTCONN:
880 		v.val = sk->sk_state == TCP_LISTEN;
881 		break;
882 
883 	case SO_PASSSEC:
884 		v.val = test_bit(SOCK_PASSSEC, &sock->flags) ? 1 : 0;
885 		break;
886 
887 	case SO_PEERSEC:
888 		return security_socket_getpeersec_stream(sock, optval, optlen, len);
889 
890 	case SO_MARK:
891 		v.val = sk->sk_mark;
892 		break;
893 
894 	default:
895 		return -ENOPROTOOPT;
896 	}
897 
898 	if (len > lv)
899 		len = lv;
900 	if (copy_to_user(optval, &v, len))
901 		return -EFAULT;
902 lenout:
903 	if (put_user(len, optlen))
904 		return -EFAULT;
905 	return 0;
906 }
907 
908 /*
909  * Initialize an sk_lock.
910  *
911  * (We also register the sk_lock with the lock validator.)
912  */
913 static inline void sock_lock_init(struct sock *sk)
914 {
915 	sock_lock_init_class_and_name(sk,
916 			af_family_slock_key_strings[sk->sk_family],
917 			af_family_slock_keys + sk->sk_family,
918 			af_family_key_strings[sk->sk_family],
919 			af_family_keys + sk->sk_family);
920 }
921 
922 static void sock_copy(struct sock *nsk, const struct sock *osk)
923 {
924 #ifdef CONFIG_SECURITY_NETWORK
925 	void *sptr = nsk->sk_security;
926 #endif
927 
928 	memcpy(nsk, osk, osk->sk_prot->obj_size);
929 #ifdef CONFIG_SECURITY_NETWORK
930 	nsk->sk_security = sptr;
931 	security_sk_clone(osk, nsk);
932 #endif
933 }
934 
935 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
936 		int family)
937 {
938 	struct sock *sk;
939 	struct kmem_cache *slab;
940 
941 	slab = prot->slab;
942 	if (slab != NULL)
943 		sk = kmem_cache_alloc(slab, priority);
944 	else
945 		sk = kmalloc(prot->obj_size, priority);
946 
947 	if (sk != NULL) {
948 		if (security_sk_alloc(sk, family, priority))
949 			goto out_free;
950 
951 		if (!try_module_get(prot->owner))
952 			goto out_free_sec;
953 	}
954 
955 	return sk;
956 
957 out_free_sec:
958 	security_sk_free(sk);
959 out_free:
960 	if (slab != NULL)
961 		kmem_cache_free(slab, sk);
962 	else
963 		kfree(sk);
964 	return NULL;
965 }
966 
967 static void sk_prot_free(struct proto *prot, struct sock *sk)
968 {
969 	struct kmem_cache *slab;
970 	struct module *owner;
971 
972 	owner = prot->owner;
973 	slab = prot->slab;
974 
975 	security_sk_free(sk);
976 	if (slab != NULL)
977 		kmem_cache_free(slab, sk);
978 	else
979 		kfree(sk);
980 	module_put(owner);
981 }
982 
983 /**
984  *	sk_alloc - All socket objects are allocated here
985  *	@net: the applicable net namespace
986  *	@family: protocol family
987  *	@priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
988  *	@prot: struct proto associated with this new sock instance
989  */
990 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
991 		      struct proto *prot)
992 {
993 	struct sock *sk;
994 
995 	sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
996 	if (sk) {
997 		sk->sk_family = family;
998 		/*
999 		 * See comment in struct sock definition to understand
1000 		 * why we need sk_prot_creator -acme
1001 		 */
1002 		sk->sk_prot = sk->sk_prot_creator = prot;
1003 		sock_lock_init(sk);
1004 		sock_net_set(sk, get_net(net));
1005 	}
1006 
1007 	return sk;
1008 }
1009 EXPORT_SYMBOL(sk_alloc);
1010 
1011 static void __sk_free(struct sock *sk)
1012 {
1013 	struct sk_filter *filter;
1014 
1015 	if (sk->sk_destruct)
1016 		sk->sk_destruct(sk);
1017 
1018 	filter = rcu_dereference(sk->sk_filter);
1019 	if (filter) {
1020 		sk_filter_uncharge(sk, filter);
1021 		rcu_assign_pointer(sk->sk_filter, NULL);
1022 	}
1023 
1024 	sock_disable_timestamp(sk, SOCK_TIMESTAMP);
1025 	sock_disable_timestamp(sk, SOCK_TIMESTAMPING_RX_SOFTWARE);
1026 
1027 	if (atomic_read(&sk->sk_omem_alloc))
1028 		printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n",
1029 		       __func__, atomic_read(&sk->sk_omem_alloc));
1030 
1031 	put_net(sock_net(sk));
1032 	sk_prot_free(sk->sk_prot_creator, sk);
1033 }
1034 
1035 void sk_free(struct sock *sk)
1036 {
1037 	/*
1038 	 * We substract one from sk_wmem_alloc and can know if
1039 	 * some packets are still in some tx queue.
1040 	 * If not null, sock_wfree() will call __sk_free(sk) later
1041 	 */
1042 	if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1043 		__sk_free(sk);
1044 }
1045 EXPORT_SYMBOL(sk_free);
1046 
1047 /*
1048  * Last sock_put should drop referrence to sk->sk_net. It has already
1049  * been dropped in sk_change_net. Taking referrence to stopping namespace
1050  * is not an option.
1051  * Take referrence to a socket to remove it from hash _alive_ and after that
1052  * destroy it in the context of init_net.
1053  */
1054 void sk_release_kernel(struct sock *sk)
1055 {
1056 	if (sk == NULL || sk->sk_socket == NULL)
1057 		return;
1058 
1059 	sock_hold(sk);
1060 	sock_release(sk->sk_socket);
1061 	release_net(sock_net(sk));
1062 	sock_net_set(sk, get_net(&init_net));
1063 	sock_put(sk);
1064 }
1065 EXPORT_SYMBOL(sk_release_kernel);
1066 
1067 struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
1068 {
1069 	struct sock *newsk;
1070 
1071 	newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1072 	if (newsk != NULL) {
1073 		struct sk_filter *filter;
1074 
1075 		sock_copy(newsk, sk);
1076 
1077 		/* SANITY */
1078 		get_net(sock_net(newsk));
1079 		sk_node_init(&newsk->sk_node);
1080 		sock_lock_init(newsk);
1081 		bh_lock_sock(newsk);
1082 		newsk->sk_backlog.head	= newsk->sk_backlog.tail = NULL;
1083 
1084 		atomic_set(&newsk->sk_rmem_alloc, 0);
1085 		/*
1086 		 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1087 		 */
1088 		atomic_set(&newsk->sk_wmem_alloc, 1);
1089 		atomic_set(&newsk->sk_omem_alloc, 0);
1090 		skb_queue_head_init(&newsk->sk_receive_queue);
1091 		skb_queue_head_init(&newsk->sk_write_queue);
1092 #ifdef CONFIG_NET_DMA
1093 		skb_queue_head_init(&newsk->sk_async_wait_queue);
1094 #endif
1095 
1096 		rwlock_init(&newsk->sk_dst_lock);
1097 		rwlock_init(&newsk->sk_callback_lock);
1098 		lockdep_set_class_and_name(&newsk->sk_callback_lock,
1099 				af_callback_keys + newsk->sk_family,
1100 				af_family_clock_key_strings[newsk->sk_family]);
1101 
1102 		newsk->sk_dst_cache	= NULL;
1103 		newsk->sk_wmem_queued	= 0;
1104 		newsk->sk_forward_alloc = 0;
1105 		newsk->sk_send_head	= NULL;
1106 		newsk->sk_userlocks	= sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1107 
1108 		sock_reset_flag(newsk, SOCK_DONE);
1109 		skb_queue_head_init(&newsk->sk_error_queue);
1110 
1111 		filter = newsk->sk_filter;
1112 		if (filter != NULL)
1113 			sk_filter_charge(newsk, filter);
1114 
1115 		if (unlikely(xfrm_sk_clone_policy(newsk))) {
1116 			/* It is still raw copy of parent, so invalidate
1117 			 * destructor and make plain sk_free() */
1118 			newsk->sk_destruct = NULL;
1119 			sk_free(newsk);
1120 			newsk = NULL;
1121 			goto out;
1122 		}
1123 
1124 		newsk->sk_err	   = 0;
1125 		newsk->sk_priority = 0;
1126 		atomic_set(&newsk->sk_refcnt, 2);
1127 
1128 		/*
1129 		 * Increment the counter in the same struct proto as the master
1130 		 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1131 		 * is the same as sk->sk_prot->socks, as this field was copied
1132 		 * with memcpy).
1133 		 *
1134 		 * This _changes_ the previous behaviour, where
1135 		 * tcp_create_openreq_child always was incrementing the
1136 		 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1137 		 * to be taken into account in all callers. -acme
1138 		 */
1139 		sk_refcnt_debug_inc(newsk);
1140 		sk_set_socket(newsk, NULL);
1141 		newsk->sk_sleep	 = NULL;
1142 
1143 		if (newsk->sk_prot->sockets_allocated)
1144 			percpu_counter_inc(newsk->sk_prot->sockets_allocated);
1145 	}
1146 out:
1147 	return newsk;
1148 }
1149 EXPORT_SYMBOL_GPL(sk_clone);
1150 
1151 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1152 {
1153 	__sk_dst_set(sk, dst);
1154 	sk->sk_route_caps = dst->dev->features;
1155 	if (sk->sk_route_caps & NETIF_F_GSO)
1156 		sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1157 	if (sk_can_gso(sk)) {
1158 		if (dst->header_len) {
1159 			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1160 		} else {
1161 			sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1162 			sk->sk_gso_max_size = dst->dev->gso_max_size;
1163 		}
1164 	}
1165 }
1166 EXPORT_SYMBOL_GPL(sk_setup_caps);
1167 
1168 void __init sk_init(void)
1169 {
1170 	if (num_physpages <= 4096) {
1171 		sysctl_wmem_max = 32767;
1172 		sysctl_rmem_max = 32767;
1173 		sysctl_wmem_default = 32767;
1174 		sysctl_rmem_default = 32767;
1175 	} else if (num_physpages >= 131072) {
1176 		sysctl_wmem_max = 131071;
1177 		sysctl_rmem_max = 131071;
1178 	}
1179 }
1180 
1181 /*
1182  *	Simple resource managers for sockets.
1183  */
1184 
1185 
1186 /*
1187  * Write buffer destructor automatically called from kfree_skb.
1188  */
1189 void sock_wfree(struct sk_buff *skb)
1190 {
1191 	struct sock *sk = skb->sk;
1192 	int res;
1193 
1194 	/* In case it might be waiting for more memory. */
1195 	res = atomic_sub_return(skb->truesize, &sk->sk_wmem_alloc);
1196 	if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE))
1197 		sk->sk_write_space(sk);
1198 	/*
1199 	 * if sk_wmem_alloc reached 0, we are last user and should
1200 	 * free this sock, as sk_free() call could not do it.
1201 	 */
1202 	if (res == 0)
1203 		__sk_free(sk);
1204 }
1205 EXPORT_SYMBOL(sock_wfree);
1206 
1207 /*
1208  * Read buffer destructor automatically called from kfree_skb.
1209  */
1210 void sock_rfree(struct sk_buff *skb)
1211 {
1212 	struct sock *sk = skb->sk;
1213 
1214 	atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
1215 	sk_mem_uncharge(skb->sk, skb->truesize);
1216 }
1217 EXPORT_SYMBOL(sock_rfree);
1218 
1219 
1220 int sock_i_uid(struct sock *sk)
1221 {
1222 	int uid;
1223 
1224 	read_lock(&sk->sk_callback_lock);
1225 	uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1226 	read_unlock(&sk->sk_callback_lock);
1227 	return uid;
1228 }
1229 EXPORT_SYMBOL(sock_i_uid);
1230 
1231 unsigned long sock_i_ino(struct sock *sk)
1232 {
1233 	unsigned long ino;
1234 
1235 	read_lock(&sk->sk_callback_lock);
1236 	ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1237 	read_unlock(&sk->sk_callback_lock);
1238 	return ino;
1239 }
1240 EXPORT_SYMBOL(sock_i_ino);
1241 
1242 /*
1243  * Allocate a skb from the socket's send buffer.
1244  */
1245 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1246 			     gfp_t priority)
1247 {
1248 	if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1249 		struct sk_buff *skb = alloc_skb(size, priority);
1250 		if (skb) {
1251 			skb_set_owner_w(skb, sk);
1252 			return skb;
1253 		}
1254 	}
1255 	return NULL;
1256 }
1257 EXPORT_SYMBOL(sock_wmalloc);
1258 
1259 /*
1260  * Allocate a skb from the socket's receive buffer.
1261  */
1262 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1263 			     gfp_t priority)
1264 {
1265 	if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1266 		struct sk_buff *skb = alloc_skb(size, priority);
1267 		if (skb) {
1268 			skb_set_owner_r(skb, sk);
1269 			return skb;
1270 		}
1271 	}
1272 	return NULL;
1273 }
1274 
1275 /*
1276  * Allocate a memory block from the socket's option memory buffer.
1277  */
1278 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1279 {
1280 	if ((unsigned)size <= sysctl_optmem_max &&
1281 	    atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1282 		void *mem;
1283 		/* First do the add, to avoid the race if kmalloc
1284 		 * might sleep.
1285 		 */
1286 		atomic_add(size, &sk->sk_omem_alloc);
1287 		mem = kmalloc(size, priority);
1288 		if (mem)
1289 			return mem;
1290 		atomic_sub(size, &sk->sk_omem_alloc);
1291 	}
1292 	return NULL;
1293 }
1294 EXPORT_SYMBOL(sock_kmalloc);
1295 
1296 /*
1297  * Free an option memory block.
1298  */
1299 void sock_kfree_s(struct sock *sk, void *mem, int size)
1300 {
1301 	kfree(mem);
1302 	atomic_sub(size, &sk->sk_omem_alloc);
1303 }
1304 EXPORT_SYMBOL(sock_kfree_s);
1305 
1306 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1307    I think, these locks should be removed for datagram sockets.
1308  */
1309 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1310 {
1311 	DEFINE_WAIT(wait);
1312 
1313 	clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1314 	for (;;) {
1315 		if (!timeo)
1316 			break;
1317 		if (signal_pending(current))
1318 			break;
1319 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1320 		prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
1321 		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1322 			break;
1323 		if (sk->sk_shutdown & SEND_SHUTDOWN)
1324 			break;
1325 		if (sk->sk_err)
1326 			break;
1327 		timeo = schedule_timeout(timeo);
1328 	}
1329 	finish_wait(sk->sk_sleep, &wait);
1330 	return timeo;
1331 }
1332 
1333 
1334 /*
1335  *	Generic send/receive buffer handlers
1336  */
1337 
1338 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1339 				     unsigned long data_len, int noblock,
1340 				     int *errcode)
1341 {
1342 	struct sk_buff *skb;
1343 	gfp_t gfp_mask;
1344 	long timeo;
1345 	int err;
1346 
1347 	gfp_mask = sk->sk_allocation;
1348 	if (gfp_mask & __GFP_WAIT)
1349 		gfp_mask |= __GFP_REPEAT;
1350 
1351 	timeo = sock_sndtimeo(sk, noblock);
1352 	while (1) {
1353 		err = sock_error(sk);
1354 		if (err != 0)
1355 			goto failure;
1356 
1357 		err = -EPIPE;
1358 		if (sk->sk_shutdown & SEND_SHUTDOWN)
1359 			goto failure;
1360 
1361 		if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1362 			skb = alloc_skb(header_len, gfp_mask);
1363 			if (skb) {
1364 				int npages;
1365 				int i;
1366 
1367 				/* No pages, we're done... */
1368 				if (!data_len)
1369 					break;
1370 
1371 				npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1372 				skb->truesize += data_len;
1373 				skb_shinfo(skb)->nr_frags = npages;
1374 				for (i = 0; i < npages; i++) {
1375 					struct page *page;
1376 					skb_frag_t *frag;
1377 
1378 					page = alloc_pages(sk->sk_allocation, 0);
1379 					if (!page) {
1380 						err = -ENOBUFS;
1381 						skb_shinfo(skb)->nr_frags = i;
1382 						kfree_skb(skb);
1383 						goto failure;
1384 					}
1385 
1386 					frag = &skb_shinfo(skb)->frags[i];
1387 					frag->page = page;
1388 					frag->page_offset = 0;
1389 					frag->size = (data_len >= PAGE_SIZE ?
1390 						      PAGE_SIZE :
1391 						      data_len);
1392 					data_len -= PAGE_SIZE;
1393 				}
1394 
1395 				/* Full success... */
1396 				break;
1397 			}
1398 			err = -ENOBUFS;
1399 			goto failure;
1400 		}
1401 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1402 		set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1403 		err = -EAGAIN;
1404 		if (!timeo)
1405 			goto failure;
1406 		if (signal_pending(current))
1407 			goto interrupted;
1408 		timeo = sock_wait_for_wmem(sk, timeo);
1409 	}
1410 
1411 	skb_set_owner_w(skb, sk);
1412 	return skb;
1413 
1414 interrupted:
1415 	err = sock_intr_errno(timeo);
1416 failure:
1417 	*errcode = err;
1418 	return NULL;
1419 }
1420 EXPORT_SYMBOL(sock_alloc_send_pskb);
1421 
1422 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1423 				    int noblock, int *errcode)
1424 {
1425 	return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1426 }
1427 EXPORT_SYMBOL(sock_alloc_send_skb);
1428 
1429 static void __lock_sock(struct sock *sk)
1430 {
1431 	DEFINE_WAIT(wait);
1432 
1433 	for (;;) {
1434 		prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1435 					TASK_UNINTERRUPTIBLE);
1436 		spin_unlock_bh(&sk->sk_lock.slock);
1437 		schedule();
1438 		spin_lock_bh(&sk->sk_lock.slock);
1439 		if (!sock_owned_by_user(sk))
1440 			break;
1441 	}
1442 	finish_wait(&sk->sk_lock.wq, &wait);
1443 }
1444 
1445 static void __release_sock(struct sock *sk)
1446 {
1447 	struct sk_buff *skb = sk->sk_backlog.head;
1448 
1449 	do {
1450 		sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1451 		bh_unlock_sock(sk);
1452 
1453 		do {
1454 			struct sk_buff *next = skb->next;
1455 
1456 			skb->next = NULL;
1457 			sk_backlog_rcv(sk, skb);
1458 
1459 			/*
1460 			 * We are in process context here with softirqs
1461 			 * disabled, use cond_resched_softirq() to preempt.
1462 			 * This is safe to do because we've taken the backlog
1463 			 * queue private:
1464 			 */
1465 			cond_resched_softirq();
1466 
1467 			skb = next;
1468 		} while (skb != NULL);
1469 
1470 		bh_lock_sock(sk);
1471 	} while ((skb = sk->sk_backlog.head) != NULL);
1472 }
1473 
1474 /**
1475  * sk_wait_data - wait for data to arrive at sk_receive_queue
1476  * @sk:    sock to wait on
1477  * @timeo: for how long
1478  *
1479  * Now socket state including sk->sk_err is changed only under lock,
1480  * hence we may omit checks after joining wait queue.
1481  * We check receive queue before schedule() only as optimization;
1482  * it is very likely that release_sock() added new data.
1483  */
1484 int sk_wait_data(struct sock *sk, long *timeo)
1485 {
1486 	int rc;
1487 	DEFINE_WAIT(wait);
1488 
1489 	prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE);
1490 	set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1491 	rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1492 	clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1493 	finish_wait(sk->sk_sleep, &wait);
1494 	return rc;
1495 }
1496 EXPORT_SYMBOL(sk_wait_data);
1497 
1498 /**
1499  *	__sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1500  *	@sk: socket
1501  *	@size: memory size to allocate
1502  *	@kind: allocation type
1503  *
1504  *	If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1505  *	rmem allocation. This function assumes that protocols which have
1506  *	memory_pressure use sk_wmem_queued as write buffer accounting.
1507  */
1508 int __sk_mem_schedule(struct sock *sk, int size, int kind)
1509 {
1510 	struct proto *prot = sk->sk_prot;
1511 	int amt = sk_mem_pages(size);
1512 	int allocated;
1513 
1514 	sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1515 	allocated = atomic_add_return(amt, prot->memory_allocated);
1516 
1517 	/* Under limit. */
1518 	if (allocated <= prot->sysctl_mem[0]) {
1519 		if (prot->memory_pressure && *prot->memory_pressure)
1520 			*prot->memory_pressure = 0;
1521 		return 1;
1522 	}
1523 
1524 	/* Under pressure. */
1525 	if (allocated > prot->sysctl_mem[1])
1526 		if (prot->enter_memory_pressure)
1527 			prot->enter_memory_pressure(sk);
1528 
1529 	/* Over hard limit. */
1530 	if (allocated > prot->sysctl_mem[2])
1531 		goto suppress_allocation;
1532 
1533 	/* guarantee minimum buffer size under pressure */
1534 	if (kind == SK_MEM_RECV) {
1535 		if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1536 			return 1;
1537 	} else { /* SK_MEM_SEND */
1538 		if (sk->sk_type == SOCK_STREAM) {
1539 			if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1540 				return 1;
1541 		} else if (atomic_read(&sk->sk_wmem_alloc) <
1542 			   prot->sysctl_wmem[0])
1543 				return 1;
1544 	}
1545 
1546 	if (prot->memory_pressure) {
1547 		int alloc;
1548 
1549 		if (!*prot->memory_pressure)
1550 			return 1;
1551 		alloc = percpu_counter_read_positive(prot->sockets_allocated);
1552 		if (prot->sysctl_mem[2] > alloc *
1553 		    sk_mem_pages(sk->sk_wmem_queued +
1554 				 atomic_read(&sk->sk_rmem_alloc) +
1555 				 sk->sk_forward_alloc))
1556 			return 1;
1557 	}
1558 
1559 suppress_allocation:
1560 
1561 	if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1562 		sk_stream_moderate_sndbuf(sk);
1563 
1564 		/* Fail only if socket is _under_ its sndbuf.
1565 		 * In this case we cannot block, so that we have to fail.
1566 		 */
1567 		if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1568 			return 1;
1569 	}
1570 
1571 	/* Alas. Undo changes. */
1572 	sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1573 	atomic_sub(amt, prot->memory_allocated);
1574 	return 0;
1575 }
1576 EXPORT_SYMBOL(__sk_mem_schedule);
1577 
1578 /**
1579  *	__sk_reclaim - reclaim memory_allocated
1580  *	@sk: socket
1581  */
1582 void __sk_mem_reclaim(struct sock *sk)
1583 {
1584 	struct proto *prot = sk->sk_prot;
1585 
1586 	atomic_sub(sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT,
1587 		   prot->memory_allocated);
1588 	sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1589 
1590 	if (prot->memory_pressure && *prot->memory_pressure &&
1591 	    (atomic_read(prot->memory_allocated) < prot->sysctl_mem[0]))
1592 		*prot->memory_pressure = 0;
1593 }
1594 EXPORT_SYMBOL(__sk_mem_reclaim);
1595 
1596 
1597 /*
1598  * Set of default routines for initialising struct proto_ops when
1599  * the protocol does not support a particular function. In certain
1600  * cases where it makes no sense for a protocol to have a "do nothing"
1601  * function, some default processing is provided.
1602  */
1603 
1604 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1605 {
1606 	return -EOPNOTSUPP;
1607 }
1608 EXPORT_SYMBOL(sock_no_bind);
1609 
1610 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1611 		    int len, int flags)
1612 {
1613 	return -EOPNOTSUPP;
1614 }
1615 EXPORT_SYMBOL(sock_no_connect);
1616 
1617 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1618 {
1619 	return -EOPNOTSUPP;
1620 }
1621 EXPORT_SYMBOL(sock_no_socketpair);
1622 
1623 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1624 {
1625 	return -EOPNOTSUPP;
1626 }
1627 EXPORT_SYMBOL(sock_no_accept);
1628 
1629 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1630 		    int *len, int peer)
1631 {
1632 	return -EOPNOTSUPP;
1633 }
1634 EXPORT_SYMBOL(sock_no_getname);
1635 
1636 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1637 {
1638 	return 0;
1639 }
1640 EXPORT_SYMBOL(sock_no_poll);
1641 
1642 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1643 {
1644 	return -EOPNOTSUPP;
1645 }
1646 EXPORT_SYMBOL(sock_no_ioctl);
1647 
1648 int sock_no_listen(struct socket *sock, int backlog)
1649 {
1650 	return -EOPNOTSUPP;
1651 }
1652 EXPORT_SYMBOL(sock_no_listen);
1653 
1654 int sock_no_shutdown(struct socket *sock, int how)
1655 {
1656 	return -EOPNOTSUPP;
1657 }
1658 EXPORT_SYMBOL(sock_no_shutdown);
1659 
1660 int sock_no_setsockopt(struct socket *sock, int level, int optname,
1661 		    char __user *optval, int optlen)
1662 {
1663 	return -EOPNOTSUPP;
1664 }
1665 EXPORT_SYMBOL(sock_no_setsockopt);
1666 
1667 int sock_no_getsockopt(struct socket *sock, int level, int optname,
1668 		    char __user *optval, int __user *optlen)
1669 {
1670 	return -EOPNOTSUPP;
1671 }
1672 EXPORT_SYMBOL(sock_no_getsockopt);
1673 
1674 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1675 		    size_t len)
1676 {
1677 	return -EOPNOTSUPP;
1678 }
1679 EXPORT_SYMBOL(sock_no_sendmsg);
1680 
1681 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1682 		    size_t len, int flags)
1683 {
1684 	return -EOPNOTSUPP;
1685 }
1686 EXPORT_SYMBOL(sock_no_recvmsg);
1687 
1688 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1689 {
1690 	/* Mirror missing mmap method error code */
1691 	return -ENODEV;
1692 }
1693 EXPORT_SYMBOL(sock_no_mmap);
1694 
1695 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
1696 {
1697 	ssize_t res;
1698 	struct msghdr msg = {.msg_flags = flags};
1699 	struct kvec iov;
1700 	char *kaddr = kmap(page);
1701 	iov.iov_base = kaddr + offset;
1702 	iov.iov_len = size;
1703 	res = kernel_sendmsg(sock, &msg, &iov, 1, size);
1704 	kunmap(page);
1705 	return res;
1706 }
1707 EXPORT_SYMBOL(sock_no_sendpage);
1708 
1709 /*
1710  *	Default Socket Callbacks
1711  */
1712 
1713 static void sock_def_wakeup(struct sock *sk)
1714 {
1715 	read_lock(&sk->sk_callback_lock);
1716 	if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1717 		wake_up_interruptible_all(sk->sk_sleep);
1718 	read_unlock(&sk->sk_callback_lock);
1719 }
1720 
1721 static void sock_def_error_report(struct sock *sk)
1722 {
1723 	read_lock(&sk->sk_callback_lock);
1724 	if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1725 		wake_up_interruptible_poll(sk->sk_sleep, POLLERR);
1726 	sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
1727 	read_unlock(&sk->sk_callback_lock);
1728 }
1729 
1730 static void sock_def_readable(struct sock *sk, int len)
1731 {
1732 	read_lock(&sk->sk_callback_lock);
1733 	if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1734 		wake_up_interruptible_sync_poll(sk->sk_sleep, POLLIN |
1735 						POLLRDNORM | POLLRDBAND);
1736 	sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
1737 	read_unlock(&sk->sk_callback_lock);
1738 }
1739 
1740 static void sock_def_write_space(struct sock *sk)
1741 {
1742 	read_lock(&sk->sk_callback_lock);
1743 
1744 	/* Do not wake up a writer until he can make "significant"
1745 	 * progress.  --DaveM
1746 	 */
1747 	if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
1748 		if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
1749 			wake_up_interruptible_sync_poll(sk->sk_sleep, POLLOUT |
1750 						POLLWRNORM | POLLWRBAND);
1751 
1752 		/* Should agree with poll, otherwise some programs break */
1753 		if (sock_writeable(sk))
1754 			sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
1755 	}
1756 
1757 	read_unlock(&sk->sk_callback_lock);
1758 }
1759 
1760 static void sock_def_destruct(struct sock *sk)
1761 {
1762 	kfree(sk->sk_protinfo);
1763 }
1764 
1765 void sk_send_sigurg(struct sock *sk)
1766 {
1767 	if (sk->sk_socket && sk->sk_socket->file)
1768 		if (send_sigurg(&sk->sk_socket->file->f_owner))
1769 			sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
1770 }
1771 EXPORT_SYMBOL(sk_send_sigurg);
1772 
1773 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1774 		    unsigned long expires)
1775 {
1776 	if (!mod_timer(timer, expires))
1777 		sock_hold(sk);
1778 }
1779 EXPORT_SYMBOL(sk_reset_timer);
1780 
1781 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
1782 {
1783 	if (timer_pending(timer) && del_timer(timer))
1784 		__sock_put(sk);
1785 }
1786 EXPORT_SYMBOL(sk_stop_timer);
1787 
1788 void sock_init_data(struct socket *sock, struct sock *sk)
1789 {
1790 	skb_queue_head_init(&sk->sk_receive_queue);
1791 	skb_queue_head_init(&sk->sk_write_queue);
1792 	skb_queue_head_init(&sk->sk_error_queue);
1793 #ifdef CONFIG_NET_DMA
1794 	skb_queue_head_init(&sk->sk_async_wait_queue);
1795 #endif
1796 
1797 	sk->sk_send_head	=	NULL;
1798 
1799 	init_timer(&sk->sk_timer);
1800 
1801 	sk->sk_allocation	=	GFP_KERNEL;
1802 	sk->sk_rcvbuf		=	sysctl_rmem_default;
1803 	sk->sk_sndbuf		=	sysctl_wmem_default;
1804 	sk->sk_state		=	TCP_CLOSE;
1805 	sk_set_socket(sk, sock);
1806 
1807 	sock_set_flag(sk, SOCK_ZAPPED);
1808 
1809 	if (sock) {
1810 		sk->sk_type	=	sock->type;
1811 		sk->sk_sleep	=	&sock->wait;
1812 		sock->sk	=	sk;
1813 	} else
1814 		sk->sk_sleep	=	NULL;
1815 
1816 	rwlock_init(&sk->sk_dst_lock);
1817 	rwlock_init(&sk->sk_callback_lock);
1818 	lockdep_set_class_and_name(&sk->sk_callback_lock,
1819 			af_callback_keys + sk->sk_family,
1820 			af_family_clock_key_strings[sk->sk_family]);
1821 
1822 	sk->sk_state_change	=	sock_def_wakeup;
1823 	sk->sk_data_ready	=	sock_def_readable;
1824 	sk->sk_write_space	=	sock_def_write_space;
1825 	sk->sk_error_report	=	sock_def_error_report;
1826 	sk->sk_destruct		=	sock_def_destruct;
1827 
1828 	sk->sk_sndmsg_page	=	NULL;
1829 	sk->sk_sndmsg_off	=	0;
1830 
1831 	sk->sk_peercred.pid 	=	0;
1832 	sk->sk_peercred.uid	=	-1;
1833 	sk->sk_peercred.gid	=	-1;
1834 	sk->sk_write_pending	=	0;
1835 	sk->sk_rcvlowat		=	1;
1836 	sk->sk_rcvtimeo		=	MAX_SCHEDULE_TIMEOUT;
1837 	sk->sk_sndtimeo		=	MAX_SCHEDULE_TIMEOUT;
1838 
1839 	sk->sk_stamp = ktime_set(-1L, 0);
1840 
1841 	atomic_set(&sk->sk_refcnt, 1);
1842 	atomic_set(&sk->sk_wmem_alloc, 1);
1843 	atomic_set(&sk->sk_drops, 0);
1844 }
1845 EXPORT_SYMBOL(sock_init_data);
1846 
1847 void lock_sock_nested(struct sock *sk, int subclass)
1848 {
1849 	might_sleep();
1850 	spin_lock_bh(&sk->sk_lock.slock);
1851 	if (sk->sk_lock.owned)
1852 		__lock_sock(sk);
1853 	sk->sk_lock.owned = 1;
1854 	spin_unlock(&sk->sk_lock.slock);
1855 	/*
1856 	 * The sk_lock has mutex_lock() semantics here:
1857 	 */
1858 	mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
1859 	local_bh_enable();
1860 }
1861 EXPORT_SYMBOL(lock_sock_nested);
1862 
1863 void release_sock(struct sock *sk)
1864 {
1865 	/*
1866 	 * The sk_lock has mutex_unlock() semantics:
1867 	 */
1868 	mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
1869 
1870 	spin_lock_bh(&sk->sk_lock.slock);
1871 	if (sk->sk_backlog.tail)
1872 		__release_sock(sk);
1873 	sk->sk_lock.owned = 0;
1874 	if (waitqueue_active(&sk->sk_lock.wq))
1875 		wake_up(&sk->sk_lock.wq);
1876 	spin_unlock_bh(&sk->sk_lock.slock);
1877 }
1878 EXPORT_SYMBOL(release_sock);
1879 
1880 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
1881 {
1882 	struct timeval tv;
1883 	if (!sock_flag(sk, SOCK_TIMESTAMP))
1884 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
1885 	tv = ktime_to_timeval(sk->sk_stamp);
1886 	if (tv.tv_sec == -1)
1887 		return -ENOENT;
1888 	if (tv.tv_sec == 0) {
1889 		sk->sk_stamp = ktime_get_real();
1890 		tv = ktime_to_timeval(sk->sk_stamp);
1891 	}
1892 	return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
1893 }
1894 EXPORT_SYMBOL(sock_get_timestamp);
1895 
1896 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
1897 {
1898 	struct timespec ts;
1899 	if (!sock_flag(sk, SOCK_TIMESTAMP))
1900 		sock_enable_timestamp(sk, SOCK_TIMESTAMP);
1901 	ts = ktime_to_timespec(sk->sk_stamp);
1902 	if (ts.tv_sec == -1)
1903 		return -ENOENT;
1904 	if (ts.tv_sec == 0) {
1905 		sk->sk_stamp = ktime_get_real();
1906 		ts = ktime_to_timespec(sk->sk_stamp);
1907 	}
1908 	return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
1909 }
1910 EXPORT_SYMBOL(sock_get_timestampns);
1911 
1912 void sock_enable_timestamp(struct sock *sk, int flag)
1913 {
1914 	if (!sock_flag(sk, flag)) {
1915 		sock_set_flag(sk, flag);
1916 		/*
1917 		 * we just set one of the two flags which require net
1918 		 * time stamping, but time stamping might have been on
1919 		 * already because of the other one
1920 		 */
1921 		if (!sock_flag(sk,
1922 				flag == SOCK_TIMESTAMP ?
1923 				SOCK_TIMESTAMPING_RX_SOFTWARE :
1924 				SOCK_TIMESTAMP))
1925 			net_enable_timestamp();
1926 	}
1927 }
1928 
1929 /*
1930  *	Get a socket option on an socket.
1931  *
1932  *	FIX: POSIX 1003.1g is very ambiguous here. It states that
1933  *	asynchronous errors should be reported by getsockopt. We assume
1934  *	this means if you specify SO_ERROR (otherwise whats the point of it).
1935  */
1936 int sock_common_getsockopt(struct socket *sock, int level, int optname,
1937 			   char __user *optval, int __user *optlen)
1938 {
1939 	struct sock *sk = sock->sk;
1940 
1941 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
1942 }
1943 EXPORT_SYMBOL(sock_common_getsockopt);
1944 
1945 #ifdef CONFIG_COMPAT
1946 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
1947 				  char __user *optval, int __user *optlen)
1948 {
1949 	struct sock *sk = sock->sk;
1950 
1951 	if (sk->sk_prot->compat_getsockopt != NULL)
1952 		return sk->sk_prot->compat_getsockopt(sk, level, optname,
1953 						      optval, optlen);
1954 	return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
1955 }
1956 EXPORT_SYMBOL(compat_sock_common_getsockopt);
1957 #endif
1958 
1959 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
1960 			struct msghdr *msg, size_t size, int flags)
1961 {
1962 	struct sock *sk = sock->sk;
1963 	int addr_len = 0;
1964 	int err;
1965 
1966 	err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
1967 				   flags & ~MSG_DONTWAIT, &addr_len);
1968 	if (err >= 0)
1969 		msg->msg_namelen = addr_len;
1970 	return err;
1971 }
1972 EXPORT_SYMBOL(sock_common_recvmsg);
1973 
1974 /*
1975  *	Set socket options on an inet socket.
1976  */
1977 int sock_common_setsockopt(struct socket *sock, int level, int optname,
1978 			   char __user *optval, int optlen)
1979 {
1980 	struct sock *sk = sock->sk;
1981 
1982 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
1983 }
1984 EXPORT_SYMBOL(sock_common_setsockopt);
1985 
1986 #ifdef CONFIG_COMPAT
1987 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
1988 				  char __user *optval, int optlen)
1989 {
1990 	struct sock *sk = sock->sk;
1991 
1992 	if (sk->sk_prot->compat_setsockopt != NULL)
1993 		return sk->sk_prot->compat_setsockopt(sk, level, optname,
1994 						      optval, optlen);
1995 	return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
1996 }
1997 EXPORT_SYMBOL(compat_sock_common_setsockopt);
1998 #endif
1999 
2000 void sk_common_release(struct sock *sk)
2001 {
2002 	if (sk->sk_prot->destroy)
2003 		sk->sk_prot->destroy(sk);
2004 
2005 	/*
2006 	 * Observation: when sock_common_release is called, processes have
2007 	 * no access to socket. But net still has.
2008 	 * Step one, detach it from networking:
2009 	 *
2010 	 * A. Remove from hash tables.
2011 	 */
2012 
2013 	sk->sk_prot->unhash(sk);
2014 
2015 	/*
2016 	 * In this point socket cannot receive new packets, but it is possible
2017 	 * that some packets are in flight because some CPU runs receiver and
2018 	 * did hash table lookup before we unhashed socket. They will achieve
2019 	 * receive queue and will be purged by socket destructor.
2020 	 *
2021 	 * Also we still have packets pending on receive queue and probably,
2022 	 * our own packets waiting in device queues. sock_destroy will drain
2023 	 * receive queue, but transmitted packets will delay socket destruction
2024 	 * until the last reference will be released.
2025 	 */
2026 
2027 	sock_orphan(sk);
2028 
2029 	xfrm_sk_free_policy(sk);
2030 
2031 	sk_refcnt_debug_release(sk);
2032 	sock_put(sk);
2033 }
2034 EXPORT_SYMBOL(sk_common_release);
2035 
2036 static DEFINE_RWLOCK(proto_list_lock);
2037 static LIST_HEAD(proto_list);
2038 
2039 #ifdef CONFIG_PROC_FS
2040 #define PROTO_INUSE_NR	64	/* should be enough for the first time */
2041 struct prot_inuse {
2042 	int val[PROTO_INUSE_NR];
2043 };
2044 
2045 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2046 
2047 #ifdef CONFIG_NET_NS
2048 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2049 {
2050 	int cpu = smp_processor_id();
2051 	per_cpu_ptr(net->core.inuse, cpu)->val[prot->inuse_idx] += val;
2052 }
2053 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2054 
2055 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2056 {
2057 	int cpu, idx = prot->inuse_idx;
2058 	int res = 0;
2059 
2060 	for_each_possible_cpu(cpu)
2061 		res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2062 
2063 	return res >= 0 ? res : 0;
2064 }
2065 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2066 
2067 static int sock_inuse_init_net(struct net *net)
2068 {
2069 	net->core.inuse = alloc_percpu(struct prot_inuse);
2070 	return net->core.inuse ? 0 : -ENOMEM;
2071 }
2072 
2073 static void sock_inuse_exit_net(struct net *net)
2074 {
2075 	free_percpu(net->core.inuse);
2076 }
2077 
2078 static struct pernet_operations net_inuse_ops = {
2079 	.init = sock_inuse_init_net,
2080 	.exit = sock_inuse_exit_net,
2081 };
2082 
2083 static __init int net_inuse_init(void)
2084 {
2085 	if (register_pernet_subsys(&net_inuse_ops))
2086 		panic("Cannot initialize net inuse counters");
2087 
2088 	return 0;
2089 }
2090 
2091 core_initcall(net_inuse_init);
2092 #else
2093 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2094 
2095 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2096 {
2097 	__get_cpu_var(prot_inuse).val[prot->inuse_idx] += val;
2098 }
2099 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2100 
2101 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2102 {
2103 	int cpu, idx = prot->inuse_idx;
2104 	int res = 0;
2105 
2106 	for_each_possible_cpu(cpu)
2107 		res += per_cpu(prot_inuse, cpu).val[idx];
2108 
2109 	return res >= 0 ? res : 0;
2110 }
2111 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2112 #endif
2113 
2114 static void assign_proto_idx(struct proto *prot)
2115 {
2116 	prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2117 
2118 	if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2119 		printk(KERN_ERR "PROTO_INUSE_NR exhausted\n");
2120 		return;
2121 	}
2122 
2123 	set_bit(prot->inuse_idx, proto_inuse_idx);
2124 }
2125 
2126 static void release_proto_idx(struct proto *prot)
2127 {
2128 	if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2129 		clear_bit(prot->inuse_idx, proto_inuse_idx);
2130 }
2131 #else
2132 static inline void assign_proto_idx(struct proto *prot)
2133 {
2134 }
2135 
2136 static inline void release_proto_idx(struct proto *prot)
2137 {
2138 }
2139 #endif
2140 
2141 int proto_register(struct proto *prot, int alloc_slab)
2142 {
2143 	if (alloc_slab) {
2144 		prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2145 					SLAB_HWCACHE_ALIGN | prot->slab_flags,
2146 					NULL);
2147 
2148 		if (prot->slab == NULL) {
2149 			printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n",
2150 			       prot->name);
2151 			goto out;
2152 		}
2153 
2154 		if (prot->rsk_prot != NULL) {
2155 			static const char mask[] = "request_sock_%s";
2156 
2157 			prot->rsk_prot->slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL);
2158 			if (prot->rsk_prot->slab_name == NULL)
2159 				goto out_free_sock_slab;
2160 
2161 			sprintf(prot->rsk_prot->slab_name, mask, prot->name);
2162 			prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2163 								 prot->rsk_prot->obj_size, 0,
2164 								 SLAB_HWCACHE_ALIGN, NULL);
2165 
2166 			if (prot->rsk_prot->slab == NULL) {
2167 				printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n",
2168 				       prot->name);
2169 				goto out_free_request_sock_slab_name;
2170 			}
2171 		}
2172 
2173 		if (prot->twsk_prot != NULL) {
2174 			static const char mask[] = "tw_sock_%s";
2175 
2176 			prot->twsk_prot->twsk_slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL);
2177 
2178 			if (prot->twsk_prot->twsk_slab_name == NULL)
2179 				goto out_free_request_sock_slab;
2180 
2181 			sprintf(prot->twsk_prot->twsk_slab_name, mask, prot->name);
2182 			prot->twsk_prot->twsk_slab =
2183 				kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2184 						  prot->twsk_prot->twsk_obj_size,
2185 						  0,
2186 						  SLAB_HWCACHE_ALIGN |
2187 							prot->slab_flags,
2188 						  NULL);
2189 			if (prot->twsk_prot->twsk_slab == NULL)
2190 				goto out_free_timewait_sock_slab_name;
2191 		}
2192 	}
2193 
2194 	write_lock(&proto_list_lock);
2195 	list_add(&prot->node, &proto_list);
2196 	assign_proto_idx(prot);
2197 	write_unlock(&proto_list_lock);
2198 	return 0;
2199 
2200 out_free_timewait_sock_slab_name:
2201 	kfree(prot->twsk_prot->twsk_slab_name);
2202 out_free_request_sock_slab:
2203 	if (prot->rsk_prot && prot->rsk_prot->slab) {
2204 		kmem_cache_destroy(prot->rsk_prot->slab);
2205 		prot->rsk_prot->slab = NULL;
2206 	}
2207 out_free_request_sock_slab_name:
2208 	kfree(prot->rsk_prot->slab_name);
2209 out_free_sock_slab:
2210 	kmem_cache_destroy(prot->slab);
2211 	prot->slab = NULL;
2212 out:
2213 	return -ENOBUFS;
2214 }
2215 EXPORT_SYMBOL(proto_register);
2216 
2217 void proto_unregister(struct proto *prot)
2218 {
2219 	write_lock(&proto_list_lock);
2220 	release_proto_idx(prot);
2221 	list_del(&prot->node);
2222 	write_unlock(&proto_list_lock);
2223 
2224 	if (prot->slab != NULL) {
2225 		kmem_cache_destroy(prot->slab);
2226 		prot->slab = NULL;
2227 	}
2228 
2229 	if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2230 		kmem_cache_destroy(prot->rsk_prot->slab);
2231 		kfree(prot->rsk_prot->slab_name);
2232 		prot->rsk_prot->slab = NULL;
2233 	}
2234 
2235 	if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2236 		kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2237 		kfree(prot->twsk_prot->twsk_slab_name);
2238 		prot->twsk_prot->twsk_slab = NULL;
2239 	}
2240 }
2241 EXPORT_SYMBOL(proto_unregister);
2242 
2243 #ifdef CONFIG_PROC_FS
2244 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2245 	__acquires(proto_list_lock)
2246 {
2247 	read_lock(&proto_list_lock);
2248 	return seq_list_start_head(&proto_list, *pos);
2249 }
2250 
2251 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2252 {
2253 	return seq_list_next(v, &proto_list, pos);
2254 }
2255 
2256 static void proto_seq_stop(struct seq_file *seq, void *v)
2257 	__releases(proto_list_lock)
2258 {
2259 	read_unlock(&proto_list_lock);
2260 }
2261 
2262 static char proto_method_implemented(const void *method)
2263 {
2264 	return method == NULL ? 'n' : 'y';
2265 }
2266 
2267 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2268 {
2269 	seq_printf(seq, "%-9s %4u %6d  %6d   %-3s %6u   %-3s  %-10s "
2270 			"%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2271 		   proto->name,
2272 		   proto->obj_size,
2273 		   sock_prot_inuse_get(seq_file_net(seq), proto),
2274 		   proto->memory_allocated != NULL ? atomic_read(proto->memory_allocated) : -1,
2275 		   proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI",
2276 		   proto->max_header,
2277 		   proto->slab == NULL ? "no" : "yes",
2278 		   module_name(proto->owner),
2279 		   proto_method_implemented(proto->close),
2280 		   proto_method_implemented(proto->connect),
2281 		   proto_method_implemented(proto->disconnect),
2282 		   proto_method_implemented(proto->accept),
2283 		   proto_method_implemented(proto->ioctl),
2284 		   proto_method_implemented(proto->init),
2285 		   proto_method_implemented(proto->destroy),
2286 		   proto_method_implemented(proto->shutdown),
2287 		   proto_method_implemented(proto->setsockopt),
2288 		   proto_method_implemented(proto->getsockopt),
2289 		   proto_method_implemented(proto->sendmsg),
2290 		   proto_method_implemented(proto->recvmsg),
2291 		   proto_method_implemented(proto->sendpage),
2292 		   proto_method_implemented(proto->bind),
2293 		   proto_method_implemented(proto->backlog_rcv),
2294 		   proto_method_implemented(proto->hash),
2295 		   proto_method_implemented(proto->unhash),
2296 		   proto_method_implemented(proto->get_port),
2297 		   proto_method_implemented(proto->enter_memory_pressure));
2298 }
2299 
2300 static int proto_seq_show(struct seq_file *seq, void *v)
2301 {
2302 	if (v == &proto_list)
2303 		seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2304 			   "protocol",
2305 			   "size",
2306 			   "sockets",
2307 			   "memory",
2308 			   "press",
2309 			   "maxhdr",
2310 			   "slab",
2311 			   "module",
2312 			   "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2313 	else
2314 		proto_seq_printf(seq, list_entry(v, struct proto, node));
2315 	return 0;
2316 }
2317 
2318 static const struct seq_operations proto_seq_ops = {
2319 	.start  = proto_seq_start,
2320 	.next   = proto_seq_next,
2321 	.stop   = proto_seq_stop,
2322 	.show   = proto_seq_show,
2323 };
2324 
2325 static int proto_seq_open(struct inode *inode, struct file *file)
2326 {
2327 	return seq_open_net(inode, file, &proto_seq_ops,
2328 			    sizeof(struct seq_net_private));
2329 }
2330 
2331 static const struct file_operations proto_seq_fops = {
2332 	.owner		= THIS_MODULE,
2333 	.open		= proto_seq_open,
2334 	.read		= seq_read,
2335 	.llseek		= seq_lseek,
2336 	.release	= seq_release_net,
2337 };
2338 
2339 static __net_init int proto_init_net(struct net *net)
2340 {
2341 	if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2342 		return -ENOMEM;
2343 
2344 	return 0;
2345 }
2346 
2347 static __net_exit void proto_exit_net(struct net *net)
2348 {
2349 	proc_net_remove(net, "protocols");
2350 }
2351 
2352 
2353 static __net_initdata struct pernet_operations proto_net_ops = {
2354 	.init = proto_init_net,
2355 	.exit = proto_exit_net,
2356 };
2357 
2358 static int __init proto_init(void)
2359 {
2360 	return register_pernet_subsys(&proto_net_ops);
2361 }
2362 
2363 subsys_initcall(proto_init);
2364 
2365 #endif /* PROC_FS */
2366