PCI: Disable MPS configuration by default
[linux-btrfs-devel.git] / net / core / sock.c
blobbc745d00ea4dd31177445dcc4282afd669a33cb6
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.
6 * Generic socket support routines. Memory allocators, socket lock/release
7 * handler for protocols to use and generic option handler.
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>
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
83 * To Fix:
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.
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>
115 #include <asm/uaccess.h>
116 #include <asm/system.h>
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>
129 #include <linux/filter.h>
131 #include <trace/events/sock.h>
133 #ifdef CONFIG_INET
134 #include <net/tcp.h>
135 #endif
138 * Each address family might have different locking rules, so we have
139 * one slock key per address family:
141 static struct lock_class_key af_family_keys[AF_MAX];
142 static struct lock_class_key af_family_slock_keys[AF_MAX];
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):
149 static 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"
165 static 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"
181 static 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"
199 * sk_callback_lock locking rules are per-address-family,
200 * so split the lock classes by using a per-AF key:
202 static struct lock_class_key af_callback_keys[AF_MAX];
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.
209 #define _SK_MEM_PACKETS 256
210 #define _SK_MEM_OVERHEAD (sizeof(struct sk_buff) + 256)
211 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
212 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
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;
220 /* Maximal space eaten by iovec or ancillary data plus some space */
221 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
222 EXPORT_SYMBOL(sysctl_optmem_max);
224 #if defined(CONFIG_CGROUPS) && !defined(CONFIG_NET_CLS_CGROUP)
225 int net_cls_subsys_id = -1;
226 EXPORT_SYMBOL_GPL(net_cls_subsys_id);
227 #endif
229 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
231 struct timeval tv;
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;
240 if (tv.tv_sec < 0) {
241 static int warned __read_mostly;
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));
250 return 0;
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;
260 static void sock_warn_obsolete_bsdism(const char *name)
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++;
272 static void sock_disable_timestamp(struct sock *sk, int flag)
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();
284 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
286 int err;
287 int skb_len;
288 unsigned long flags;
289 struct sk_buff_head *list = &sk->sk_receive_queue;
291 /* Cast sk->rcvbuf to unsigned... It's pointless, but reduces
292 number of warnings when compiling with -W --ANK
294 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
295 (unsigned)sk->sk_rcvbuf) {
296 atomic_inc(&sk->sk_drops);
297 trace_sock_rcvqueue_full(sk, skb);
298 return -ENOMEM;
301 err = sk_filter(sk, skb);
302 if (err)
303 return err;
305 if (!sk_rmem_schedule(sk, skb->truesize)) {
306 atomic_inc(&sk->sk_drops);
307 return -ENOBUFS;
310 skb->dev = NULL;
311 skb_set_owner_r(skb, sk);
313 /* Cache the SKB length before we tack it onto the receive
314 * queue. Once it is added it no longer belongs to us and
315 * may be freed by other threads of control pulling packets
316 * from the queue.
318 skb_len = skb->len;
320 /* we escape from rcu protected region, make sure we dont leak
321 * a norefcounted dst
323 skb_dst_force(skb);
325 spin_lock_irqsave(&list->lock, flags);
326 skb->dropcount = atomic_read(&sk->sk_drops);
327 __skb_queue_tail(list, skb);
328 spin_unlock_irqrestore(&list->lock, flags);
330 if (!sock_flag(sk, SOCK_DEAD))
331 sk->sk_data_ready(sk, skb_len);
332 return 0;
334 EXPORT_SYMBOL(sock_queue_rcv_skb);
336 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
338 int rc = NET_RX_SUCCESS;
340 if (sk_filter(sk, skb))
341 goto discard_and_relse;
343 skb->dev = NULL;
345 if (sk_rcvqueues_full(sk, skb)) {
346 atomic_inc(&sk->sk_drops);
347 goto discard_and_relse;
349 if (nested)
350 bh_lock_sock_nested(sk);
351 else
352 bh_lock_sock(sk);
353 if (!sock_owned_by_user(sk)) {
355 * trylock + unlock semantics:
357 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
359 rc = sk_backlog_rcv(sk, skb);
361 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
362 } else if (sk_add_backlog(sk, skb)) {
363 bh_unlock_sock(sk);
364 atomic_inc(&sk->sk_drops);
365 goto discard_and_relse;
368 bh_unlock_sock(sk);
369 out:
370 sock_put(sk);
371 return rc;
372 discard_and_relse:
373 kfree_skb(skb);
374 goto out;
376 EXPORT_SYMBOL(sk_receive_skb);
378 void sk_reset_txq(struct sock *sk)
380 sk_tx_queue_clear(sk);
382 EXPORT_SYMBOL(sk_reset_txq);
384 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
386 struct dst_entry *dst = __sk_dst_get(sk);
388 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
389 sk_tx_queue_clear(sk);
390 rcu_assign_pointer(sk->sk_dst_cache, NULL);
391 dst_release(dst);
392 return NULL;
395 return dst;
397 EXPORT_SYMBOL(__sk_dst_check);
399 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
401 struct dst_entry *dst = sk_dst_get(sk);
403 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
404 sk_dst_reset(sk);
405 dst_release(dst);
406 return NULL;
409 return dst;
411 EXPORT_SYMBOL(sk_dst_check);
413 static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
415 int ret = -ENOPROTOOPT;
416 #ifdef CONFIG_NETDEVICES
417 struct net *net = sock_net(sk);
418 char devname[IFNAMSIZ];
419 int index;
421 /* Sorry... */
422 ret = -EPERM;
423 if (!capable(CAP_NET_RAW))
424 goto out;
426 ret = -EINVAL;
427 if (optlen < 0)
428 goto out;
430 /* Bind this socket to a particular device like "eth0",
431 * as specified in the passed interface name. If the
432 * name is "" or the option length is zero the socket
433 * is not bound.
435 if (optlen > IFNAMSIZ - 1)
436 optlen = IFNAMSIZ - 1;
437 memset(devname, 0, sizeof(devname));
439 ret = -EFAULT;
440 if (copy_from_user(devname, optval, optlen))
441 goto out;
443 index = 0;
444 if (devname[0] != '\0') {
445 struct net_device *dev;
447 rcu_read_lock();
448 dev = dev_get_by_name_rcu(net, devname);
449 if (dev)
450 index = dev->ifindex;
451 rcu_read_unlock();
452 ret = -ENODEV;
453 if (!dev)
454 goto out;
457 lock_sock(sk);
458 sk->sk_bound_dev_if = index;
459 sk_dst_reset(sk);
460 release_sock(sk);
462 ret = 0;
464 out:
465 #endif
467 return ret;
470 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
472 if (valbool)
473 sock_set_flag(sk, bit);
474 else
475 sock_reset_flag(sk, bit);
479 * This is meant for all protocols to use and covers goings on
480 * at the socket level. Everything here is generic.
483 int sock_setsockopt(struct socket *sock, int level, int optname,
484 char __user *optval, unsigned int optlen)
486 struct sock *sk = sock->sk;
487 int val;
488 int valbool;
489 struct linger ling;
490 int ret = 0;
493 * Options without arguments
496 if (optname == SO_BINDTODEVICE)
497 return sock_bindtodevice(sk, optval, optlen);
499 if (optlen < sizeof(int))
500 return -EINVAL;
502 if (get_user(val, (int __user *)optval))
503 return -EFAULT;
505 valbool = val ? 1 : 0;
507 lock_sock(sk);
509 switch (optname) {
510 case SO_DEBUG:
511 if (val && !capable(CAP_NET_ADMIN))
512 ret = -EACCES;
513 else
514 sock_valbool_flag(sk, SOCK_DBG, valbool);
515 break;
516 case SO_REUSEADDR:
517 sk->sk_reuse = valbool;
518 break;
519 case SO_TYPE:
520 case SO_PROTOCOL:
521 case SO_DOMAIN:
522 case SO_ERROR:
523 ret = -ENOPROTOOPT;
524 break;
525 case SO_DONTROUTE:
526 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
527 break;
528 case SO_BROADCAST:
529 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
530 break;
531 case SO_SNDBUF:
532 /* Don't error on this BSD doesn't and if you think
533 about it this is right. Otherwise apps have to
534 play 'guess the biggest size' games. RCVBUF/SNDBUF
535 are treated in BSD as hints */
537 if (val > sysctl_wmem_max)
538 val = sysctl_wmem_max;
539 set_sndbuf:
540 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
541 if ((val * 2) < SOCK_MIN_SNDBUF)
542 sk->sk_sndbuf = SOCK_MIN_SNDBUF;
543 else
544 sk->sk_sndbuf = val * 2;
547 * Wake up sending tasks if we
548 * upped the value.
550 sk->sk_write_space(sk);
551 break;
553 case SO_SNDBUFFORCE:
554 if (!capable(CAP_NET_ADMIN)) {
555 ret = -EPERM;
556 break;
558 goto set_sndbuf;
560 case SO_RCVBUF:
561 /* Don't error on this BSD doesn't and if you think
562 about it this is right. Otherwise apps have to
563 play 'guess the biggest size' games. RCVBUF/SNDBUF
564 are treated in BSD as hints */
566 if (val > sysctl_rmem_max)
567 val = sysctl_rmem_max;
568 set_rcvbuf:
569 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
571 * We double it on the way in to account for
572 * "struct sk_buff" etc. overhead. Applications
573 * assume that the SO_RCVBUF setting they make will
574 * allow that much actual data to be received on that
575 * socket.
577 * Applications are unaware that "struct sk_buff" and
578 * other overheads allocate from the receive buffer
579 * during socket buffer allocation.
581 * And after considering the possible alternatives,
582 * returning the value we actually used in getsockopt
583 * is the most desirable behavior.
585 if ((val * 2) < SOCK_MIN_RCVBUF)
586 sk->sk_rcvbuf = SOCK_MIN_RCVBUF;
587 else
588 sk->sk_rcvbuf = val * 2;
589 break;
591 case SO_RCVBUFFORCE:
592 if (!capable(CAP_NET_ADMIN)) {
593 ret = -EPERM;
594 break;
596 goto set_rcvbuf;
598 case SO_KEEPALIVE:
599 #ifdef CONFIG_INET
600 if (sk->sk_protocol == IPPROTO_TCP)
601 tcp_set_keepalive(sk, valbool);
602 #endif
603 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
604 break;
606 case SO_OOBINLINE:
607 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
608 break;
610 case SO_NO_CHECK:
611 sk->sk_no_check = valbool;
612 break;
614 case SO_PRIORITY:
615 if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
616 sk->sk_priority = val;
617 else
618 ret = -EPERM;
619 break;
621 case SO_LINGER:
622 if (optlen < sizeof(ling)) {
623 ret = -EINVAL; /* 1003.1g */
624 break;
626 if (copy_from_user(&ling, optval, sizeof(ling))) {
627 ret = -EFAULT;
628 break;
630 if (!ling.l_onoff)
631 sock_reset_flag(sk, SOCK_LINGER);
632 else {
633 #if (BITS_PER_LONG == 32)
634 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
635 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
636 else
637 #endif
638 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
639 sock_set_flag(sk, SOCK_LINGER);
641 break;
643 case SO_BSDCOMPAT:
644 sock_warn_obsolete_bsdism("setsockopt");
645 break;
647 case SO_PASSCRED:
648 if (valbool)
649 set_bit(SOCK_PASSCRED, &sock->flags);
650 else
651 clear_bit(SOCK_PASSCRED, &sock->flags);
652 break;
654 case SO_TIMESTAMP:
655 case SO_TIMESTAMPNS:
656 if (valbool) {
657 if (optname == SO_TIMESTAMP)
658 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
659 else
660 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
661 sock_set_flag(sk, SOCK_RCVTSTAMP);
662 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
663 } else {
664 sock_reset_flag(sk, SOCK_RCVTSTAMP);
665 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
667 break;
669 case SO_TIMESTAMPING:
670 if (val & ~SOF_TIMESTAMPING_MASK) {
671 ret = -EINVAL;
672 break;
674 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE,
675 val & SOF_TIMESTAMPING_TX_HARDWARE);
676 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE,
677 val & SOF_TIMESTAMPING_TX_SOFTWARE);
678 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE,
679 val & SOF_TIMESTAMPING_RX_HARDWARE);
680 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
681 sock_enable_timestamp(sk,
682 SOCK_TIMESTAMPING_RX_SOFTWARE);
683 else
684 sock_disable_timestamp(sk,
685 SOCK_TIMESTAMPING_RX_SOFTWARE);
686 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE,
687 val & SOF_TIMESTAMPING_SOFTWARE);
688 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE,
689 val & SOF_TIMESTAMPING_SYS_HARDWARE);
690 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE,
691 val & SOF_TIMESTAMPING_RAW_HARDWARE);
692 break;
694 case SO_RCVLOWAT:
695 if (val < 0)
696 val = INT_MAX;
697 sk->sk_rcvlowat = val ? : 1;
698 break;
700 case SO_RCVTIMEO:
701 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
702 break;
704 case SO_SNDTIMEO:
705 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
706 break;
708 case SO_ATTACH_FILTER:
709 ret = -EINVAL;
710 if (optlen == sizeof(struct sock_fprog)) {
711 struct sock_fprog fprog;
713 ret = -EFAULT;
714 if (copy_from_user(&fprog, optval, sizeof(fprog)))
715 break;
717 ret = sk_attach_filter(&fprog, sk);
719 break;
721 case SO_DETACH_FILTER:
722 ret = sk_detach_filter(sk);
723 break;
725 case SO_PASSSEC:
726 if (valbool)
727 set_bit(SOCK_PASSSEC, &sock->flags);
728 else
729 clear_bit(SOCK_PASSSEC, &sock->flags);
730 break;
731 case SO_MARK:
732 if (!capable(CAP_NET_ADMIN))
733 ret = -EPERM;
734 else
735 sk->sk_mark = val;
736 break;
738 /* We implement the SO_SNDLOWAT etc to
739 not be settable (1003.1g 5.3) */
740 case SO_RXQ_OVFL:
741 if (valbool)
742 sock_set_flag(sk, SOCK_RXQ_OVFL);
743 else
744 sock_reset_flag(sk, SOCK_RXQ_OVFL);
745 break;
746 default:
747 ret = -ENOPROTOOPT;
748 break;
750 release_sock(sk);
751 return ret;
753 EXPORT_SYMBOL(sock_setsockopt);
756 void cred_to_ucred(struct pid *pid, const struct cred *cred,
757 struct ucred *ucred)
759 ucred->pid = pid_vnr(pid);
760 ucred->uid = ucred->gid = -1;
761 if (cred) {
762 struct user_namespace *current_ns = current_user_ns();
764 ucred->uid = user_ns_map_uid(current_ns, cred, cred->euid);
765 ucred->gid = user_ns_map_gid(current_ns, cred, cred->egid);
768 EXPORT_SYMBOL_GPL(cred_to_ucred);
770 int sock_getsockopt(struct socket *sock, int level, int optname,
771 char __user *optval, int __user *optlen)
773 struct sock *sk = sock->sk;
775 union {
776 int val;
777 struct linger ling;
778 struct timeval tm;
779 } v;
781 int lv = sizeof(int);
782 int len;
784 if (get_user(len, optlen))
785 return -EFAULT;
786 if (len < 0)
787 return -EINVAL;
789 memset(&v, 0, sizeof(v));
791 switch (optname) {
792 case SO_DEBUG:
793 v.val = sock_flag(sk, SOCK_DBG);
794 break;
796 case SO_DONTROUTE:
797 v.val = sock_flag(sk, SOCK_LOCALROUTE);
798 break;
800 case SO_BROADCAST:
801 v.val = !!sock_flag(sk, SOCK_BROADCAST);
802 break;
804 case SO_SNDBUF:
805 v.val = sk->sk_sndbuf;
806 break;
808 case SO_RCVBUF:
809 v.val = sk->sk_rcvbuf;
810 break;
812 case SO_REUSEADDR:
813 v.val = sk->sk_reuse;
814 break;
816 case SO_KEEPALIVE:
817 v.val = !!sock_flag(sk, SOCK_KEEPOPEN);
818 break;
820 case SO_TYPE:
821 v.val = sk->sk_type;
822 break;
824 case SO_PROTOCOL:
825 v.val = sk->sk_protocol;
826 break;
828 case SO_DOMAIN:
829 v.val = sk->sk_family;
830 break;
832 case SO_ERROR:
833 v.val = -sock_error(sk);
834 if (v.val == 0)
835 v.val = xchg(&sk->sk_err_soft, 0);
836 break;
838 case SO_OOBINLINE:
839 v.val = !!sock_flag(sk, SOCK_URGINLINE);
840 break;
842 case SO_NO_CHECK:
843 v.val = sk->sk_no_check;
844 break;
846 case SO_PRIORITY:
847 v.val = sk->sk_priority;
848 break;
850 case SO_LINGER:
851 lv = sizeof(v.ling);
852 v.ling.l_onoff = !!sock_flag(sk, SOCK_LINGER);
853 v.ling.l_linger = sk->sk_lingertime / HZ;
854 break;
856 case SO_BSDCOMPAT:
857 sock_warn_obsolete_bsdism("getsockopt");
858 break;
860 case SO_TIMESTAMP:
861 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
862 !sock_flag(sk, SOCK_RCVTSTAMPNS);
863 break;
865 case SO_TIMESTAMPNS:
866 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
867 break;
869 case SO_TIMESTAMPING:
870 v.val = 0;
871 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
872 v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
873 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
874 v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
875 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
876 v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
877 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
878 v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
879 if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
880 v.val |= SOF_TIMESTAMPING_SOFTWARE;
881 if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
882 v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
883 if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
884 v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
885 break;
887 case SO_RCVTIMEO:
888 lv = sizeof(struct timeval);
889 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
890 v.tm.tv_sec = 0;
891 v.tm.tv_usec = 0;
892 } else {
893 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
894 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
896 break;
898 case SO_SNDTIMEO:
899 lv = sizeof(struct timeval);
900 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
901 v.tm.tv_sec = 0;
902 v.tm.tv_usec = 0;
903 } else {
904 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
905 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
907 break;
909 case SO_RCVLOWAT:
910 v.val = sk->sk_rcvlowat;
911 break;
913 case SO_SNDLOWAT:
914 v.val = 1;
915 break;
917 case SO_PASSCRED:
918 v.val = test_bit(SOCK_PASSCRED, &sock->flags) ? 1 : 0;
919 break;
921 case SO_PEERCRED:
923 struct ucred peercred;
924 if (len > sizeof(peercred))
925 len = sizeof(peercred);
926 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
927 if (copy_to_user(optval, &peercred, len))
928 return -EFAULT;
929 goto lenout;
932 case SO_PEERNAME:
934 char address[128];
936 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
937 return -ENOTCONN;
938 if (lv < len)
939 return -EINVAL;
940 if (copy_to_user(optval, address, len))
941 return -EFAULT;
942 goto lenout;
945 /* Dubious BSD thing... Probably nobody even uses it, but
946 * the UNIX standard wants it for whatever reason... -DaveM
948 case SO_ACCEPTCONN:
949 v.val = sk->sk_state == TCP_LISTEN;
950 break;
952 case SO_PASSSEC:
953 v.val = test_bit(SOCK_PASSSEC, &sock->flags) ? 1 : 0;
954 break;
956 case SO_PEERSEC:
957 return security_socket_getpeersec_stream(sock, optval, optlen, len);
959 case SO_MARK:
960 v.val = sk->sk_mark;
961 break;
963 case SO_RXQ_OVFL:
964 v.val = !!sock_flag(sk, SOCK_RXQ_OVFL);
965 break;
967 default:
968 return -ENOPROTOOPT;
971 if (len > lv)
972 len = lv;
973 if (copy_to_user(optval, &v, len))
974 return -EFAULT;
975 lenout:
976 if (put_user(len, optlen))
977 return -EFAULT;
978 return 0;
982 * Initialize an sk_lock.
984 * (We also register the sk_lock with the lock validator.)
986 static inline void sock_lock_init(struct sock *sk)
988 sock_lock_init_class_and_name(sk,
989 af_family_slock_key_strings[sk->sk_family],
990 af_family_slock_keys + sk->sk_family,
991 af_family_key_strings[sk->sk_family],
992 af_family_keys + sk->sk_family);
996 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
997 * even temporarly, because of RCU lookups. sk_node should also be left as is.
998 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1000 static void sock_copy(struct sock *nsk, const struct sock *osk)
1002 #ifdef CONFIG_SECURITY_NETWORK
1003 void *sptr = nsk->sk_security;
1004 #endif
1005 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1007 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1008 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1010 #ifdef CONFIG_SECURITY_NETWORK
1011 nsk->sk_security = sptr;
1012 security_sk_clone(osk, nsk);
1013 #endif
1017 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
1018 * un-modified. Special care is taken when initializing object to zero.
1020 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1022 if (offsetof(struct sock, sk_node.next) != 0)
1023 memset(sk, 0, offsetof(struct sock, sk_node.next));
1024 memset(&sk->sk_node.pprev, 0,
1025 size - offsetof(struct sock, sk_node.pprev));
1028 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1030 unsigned long nulls1, nulls2;
1032 nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1033 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1034 if (nulls1 > nulls2)
1035 swap(nulls1, nulls2);
1037 if (nulls1 != 0)
1038 memset((char *)sk, 0, nulls1);
1039 memset((char *)sk + nulls1 + sizeof(void *), 0,
1040 nulls2 - nulls1 - sizeof(void *));
1041 memset((char *)sk + nulls2 + sizeof(void *), 0,
1042 size - nulls2 - sizeof(void *));
1044 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1046 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1047 int family)
1049 struct sock *sk;
1050 struct kmem_cache *slab;
1052 slab = prot->slab;
1053 if (slab != NULL) {
1054 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1055 if (!sk)
1056 return sk;
1057 if (priority & __GFP_ZERO) {
1058 if (prot->clear_sk)
1059 prot->clear_sk(sk, prot->obj_size);
1060 else
1061 sk_prot_clear_nulls(sk, prot->obj_size);
1063 } else
1064 sk = kmalloc(prot->obj_size, priority);
1066 if (sk != NULL) {
1067 kmemcheck_annotate_bitfield(sk, flags);
1069 if (security_sk_alloc(sk, family, priority))
1070 goto out_free;
1072 if (!try_module_get(prot->owner))
1073 goto out_free_sec;
1074 sk_tx_queue_clear(sk);
1077 return sk;
1079 out_free_sec:
1080 security_sk_free(sk);
1081 out_free:
1082 if (slab != NULL)
1083 kmem_cache_free(slab, sk);
1084 else
1085 kfree(sk);
1086 return NULL;
1089 static void sk_prot_free(struct proto *prot, struct sock *sk)
1091 struct kmem_cache *slab;
1092 struct module *owner;
1094 owner = prot->owner;
1095 slab = prot->slab;
1097 security_sk_free(sk);
1098 if (slab != NULL)
1099 kmem_cache_free(slab, sk);
1100 else
1101 kfree(sk);
1102 module_put(owner);
1105 #ifdef CONFIG_CGROUPS
1106 void sock_update_classid(struct sock *sk)
1108 u32 classid;
1110 rcu_read_lock(); /* doing current task, which cannot vanish. */
1111 classid = task_cls_classid(current);
1112 rcu_read_unlock();
1113 if (classid && classid != sk->sk_classid)
1114 sk->sk_classid = classid;
1116 EXPORT_SYMBOL(sock_update_classid);
1117 #endif
1120 * sk_alloc - All socket objects are allocated here
1121 * @net: the applicable net namespace
1122 * @family: protocol family
1123 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1124 * @prot: struct proto associated with this new sock instance
1126 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1127 struct proto *prot)
1129 struct sock *sk;
1131 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1132 if (sk) {
1133 sk->sk_family = family;
1135 * See comment in struct sock definition to understand
1136 * why we need sk_prot_creator -acme
1138 sk->sk_prot = sk->sk_prot_creator = prot;
1139 sock_lock_init(sk);
1140 sock_net_set(sk, get_net(net));
1141 atomic_set(&sk->sk_wmem_alloc, 1);
1143 sock_update_classid(sk);
1146 return sk;
1148 EXPORT_SYMBOL(sk_alloc);
1150 static void __sk_free(struct sock *sk)
1152 struct sk_filter *filter;
1154 if (sk->sk_destruct)
1155 sk->sk_destruct(sk);
1157 filter = rcu_dereference_check(sk->sk_filter,
1158 atomic_read(&sk->sk_wmem_alloc) == 0);
1159 if (filter) {
1160 sk_filter_uncharge(sk, filter);
1161 rcu_assign_pointer(sk->sk_filter, NULL);
1164 sock_disable_timestamp(sk, SOCK_TIMESTAMP);
1165 sock_disable_timestamp(sk, SOCK_TIMESTAMPING_RX_SOFTWARE);
1167 if (atomic_read(&sk->sk_omem_alloc))
1168 printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n",
1169 __func__, atomic_read(&sk->sk_omem_alloc));
1171 if (sk->sk_peer_cred)
1172 put_cred(sk->sk_peer_cred);
1173 put_pid(sk->sk_peer_pid);
1174 put_net(sock_net(sk));
1175 sk_prot_free(sk->sk_prot_creator, sk);
1178 void sk_free(struct sock *sk)
1181 * We subtract one from sk_wmem_alloc and can know if
1182 * some packets are still in some tx queue.
1183 * If not null, sock_wfree() will call __sk_free(sk) later
1185 if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1186 __sk_free(sk);
1188 EXPORT_SYMBOL(sk_free);
1191 * Last sock_put should drop reference to sk->sk_net. It has already
1192 * been dropped in sk_change_net. Taking reference to stopping namespace
1193 * is not an option.
1194 * Take reference to a socket to remove it from hash _alive_ and after that
1195 * destroy it in the context of init_net.
1197 void sk_release_kernel(struct sock *sk)
1199 if (sk == NULL || sk->sk_socket == NULL)
1200 return;
1202 sock_hold(sk);
1203 sock_release(sk->sk_socket);
1204 release_net(sock_net(sk));
1205 sock_net_set(sk, get_net(&init_net));
1206 sock_put(sk);
1208 EXPORT_SYMBOL(sk_release_kernel);
1210 struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
1212 struct sock *newsk;
1214 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1215 if (newsk != NULL) {
1216 struct sk_filter *filter;
1218 sock_copy(newsk, sk);
1220 /* SANITY */
1221 get_net(sock_net(newsk));
1222 sk_node_init(&newsk->sk_node);
1223 sock_lock_init(newsk);
1224 bh_lock_sock(newsk);
1225 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1226 newsk->sk_backlog.len = 0;
1228 atomic_set(&newsk->sk_rmem_alloc, 0);
1230 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1232 atomic_set(&newsk->sk_wmem_alloc, 1);
1233 atomic_set(&newsk->sk_omem_alloc, 0);
1234 skb_queue_head_init(&newsk->sk_receive_queue);
1235 skb_queue_head_init(&newsk->sk_write_queue);
1236 #ifdef CONFIG_NET_DMA
1237 skb_queue_head_init(&newsk->sk_async_wait_queue);
1238 #endif
1240 spin_lock_init(&newsk->sk_dst_lock);
1241 rwlock_init(&newsk->sk_callback_lock);
1242 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1243 af_callback_keys + newsk->sk_family,
1244 af_family_clock_key_strings[newsk->sk_family]);
1246 newsk->sk_dst_cache = NULL;
1247 newsk->sk_wmem_queued = 0;
1248 newsk->sk_forward_alloc = 0;
1249 newsk->sk_send_head = NULL;
1250 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1252 sock_reset_flag(newsk, SOCK_DONE);
1253 skb_queue_head_init(&newsk->sk_error_queue);
1255 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1256 if (filter != NULL)
1257 sk_filter_charge(newsk, filter);
1259 if (unlikely(xfrm_sk_clone_policy(newsk))) {
1260 /* It is still raw copy of parent, so invalidate
1261 * destructor and make plain sk_free() */
1262 newsk->sk_destruct = NULL;
1263 sk_free(newsk);
1264 newsk = NULL;
1265 goto out;
1268 newsk->sk_err = 0;
1269 newsk->sk_priority = 0;
1271 * Before updating sk_refcnt, we must commit prior changes to memory
1272 * (Documentation/RCU/rculist_nulls.txt for details)
1274 smp_wmb();
1275 atomic_set(&newsk->sk_refcnt, 2);
1278 * Increment the counter in the same struct proto as the master
1279 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1280 * is the same as sk->sk_prot->socks, as this field was copied
1281 * with memcpy).
1283 * This _changes_ the previous behaviour, where
1284 * tcp_create_openreq_child always was incrementing the
1285 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1286 * to be taken into account in all callers. -acme
1288 sk_refcnt_debug_inc(newsk);
1289 sk_set_socket(newsk, NULL);
1290 newsk->sk_wq = NULL;
1292 if (newsk->sk_prot->sockets_allocated)
1293 percpu_counter_inc(newsk->sk_prot->sockets_allocated);
1295 if (sock_flag(newsk, SOCK_TIMESTAMP) ||
1296 sock_flag(newsk, SOCK_TIMESTAMPING_RX_SOFTWARE))
1297 net_enable_timestamp();
1299 out:
1300 return newsk;
1302 EXPORT_SYMBOL_GPL(sk_clone);
1304 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1306 __sk_dst_set(sk, dst);
1307 sk->sk_route_caps = dst->dev->features;
1308 if (sk->sk_route_caps & NETIF_F_GSO)
1309 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1310 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1311 if (sk_can_gso(sk)) {
1312 if (dst->header_len) {
1313 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1314 } else {
1315 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1316 sk->sk_gso_max_size = dst->dev->gso_max_size;
1320 EXPORT_SYMBOL_GPL(sk_setup_caps);
1322 void __init sk_init(void)
1324 if (totalram_pages <= 4096) {
1325 sysctl_wmem_max = 32767;
1326 sysctl_rmem_max = 32767;
1327 sysctl_wmem_default = 32767;
1328 sysctl_rmem_default = 32767;
1329 } else if (totalram_pages >= 131072) {
1330 sysctl_wmem_max = 131071;
1331 sysctl_rmem_max = 131071;
1336 * Simple resource managers for sockets.
1341 * Write buffer destructor automatically called from kfree_skb.
1343 void sock_wfree(struct sk_buff *skb)
1345 struct sock *sk = skb->sk;
1346 unsigned int len = skb->truesize;
1348 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1350 * Keep a reference on sk_wmem_alloc, this will be released
1351 * after sk_write_space() call
1353 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1354 sk->sk_write_space(sk);
1355 len = 1;
1358 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1359 * could not do because of in-flight packets
1361 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1362 __sk_free(sk);
1364 EXPORT_SYMBOL(sock_wfree);
1367 * Read buffer destructor automatically called from kfree_skb.
1369 void sock_rfree(struct sk_buff *skb)
1371 struct sock *sk = skb->sk;
1372 unsigned int len = skb->truesize;
1374 atomic_sub(len, &sk->sk_rmem_alloc);
1375 sk_mem_uncharge(sk, len);
1377 EXPORT_SYMBOL(sock_rfree);
1380 int sock_i_uid(struct sock *sk)
1382 int uid;
1384 read_lock_bh(&sk->sk_callback_lock);
1385 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1386 read_unlock_bh(&sk->sk_callback_lock);
1387 return uid;
1389 EXPORT_SYMBOL(sock_i_uid);
1391 unsigned long sock_i_ino(struct sock *sk)
1393 unsigned long ino;
1395 read_lock_bh(&sk->sk_callback_lock);
1396 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1397 read_unlock_bh(&sk->sk_callback_lock);
1398 return ino;
1400 EXPORT_SYMBOL(sock_i_ino);
1403 * Allocate a skb from the socket's send buffer.
1405 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1406 gfp_t priority)
1408 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1409 struct sk_buff *skb = alloc_skb(size, priority);
1410 if (skb) {
1411 skb_set_owner_w(skb, sk);
1412 return skb;
1415 return NULL;
1417 EXPORT_SYMBOL(sock_wmalloc);
1420 * Allocate a skb from the socket's receive buffer.
1422 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1423 gfp_t priority)
1425 if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1426 struct sk_buff *skb = alloc_skb(size, priority);
1427 if (skb) {
1428 skb_set_owner_r(skb, sk);
1429 return skb;
1432 return NULL;
1436 * Allocate a memory block from the socket's option memory buffer.
1438 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1440 if ((unsigned)size <= sysctl_optmem_max &&
1441 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1442 void *mem;
1443 /* First do the add, to avoid the race if kmalloc
1444 * might sleep.
1446 atomic_add(size, &sk->sk_omem_alloc);
1447 mem = kmalloc(size, priority);
1448 if (mem)
1449 return mem;
1450 atomic_sub(size, &sk->sk_omem_alloc);
1452 return NULL;
1454 EXPORT_SYMBOL(sock_kmalloc);
1457 * Free an option memory block.
1459 void sock_kfree_s(struct sock *sk, void *mem, int size)
1461 kfree(mem);
1462 atomic_sub(size, &sk->sk_omem_alloc);
1464 EXPORT_SYMBOL(sock_kfree_s);
1466 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1467 I think, these locks should be removed for datagram sockets.
1469 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1471 DEFINE_WAIT(wait);
1473 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1474 for (;;) {
1475 if (!timeo)
1476 break;
1477 if (signal_pending(current))
1478 break;
1479 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1480 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1481 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1482 break;
1483 if (sk->sk_shutdown & SEND_SHUTDOWN)
1484 break;
1485 if (sk->sk_err)
1486 break;
1487 timeo = schedule_timeout(timeo);
1489 finish_wait(sk_sleep(sk), &wait);
1490 return timeo;
1495 * Generic send/receive buffer handlers
1498 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1499 unsigned long data_len, int noblock,
1500 int *errcode)
1502 struct sk_buff *skb;
1503 gfp_t gfp_mask;
1504 long timeo;
1505 int err;
1507 gfp_mask = sk->sk_allocation;
1508 if (gfp_mask & __GFP_WAIT)
1509 gfp_mask |= __GFP_REPEAT;
1511 timeo = sock_sndtimeo(sk, noblock);
1512 while (1) {
1513 err = sock_error(sk);
1514 if (err != 0)
1515 goto failure;
1517 err = -EPIPE;
1518 if (sk->sk_shutdown & SEND_SHUTDOWN)
1519 goto failure;
1521 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1522 skb = alloc_skb(header_len, gfp_mask);
1523 if (skb) {
1524 int npages;
1525 int i;
1527 /* No pages, we're done... */
1528 if (!data_len)
1529 break;
1531 npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1532 skb->truesize += data_len;
1533 skb_shinfo(skb)->nr_frags = npages;
1534 for (i = 0; i < npages; i++) {
1535 struct page *page;
1536 skb_frag_t *frag;
1538 page = alloc_pages(sk->sk_allocation, 0);
1539 if (!page) {
1540 err = -ENOBUFS;
1541 skb_shinfo(skb)->nr_frags = i;
1542 kfree_skb(skb);
1543 goto failure;
1546 frag = &skb_shinfo(skb)->frags[i];
1547 frag->page = page;
1548 frag->page_offset = 0;
1549 frag->size = (data_len >= PAGE_SIZE ?
1550 PAGE_SIZE :
1551 data_len);
1552 data_len -= PAGE_SIZE;
1555 /* Full success... */
1556 break;
1558 err = -ENOBUFS;
1559 goto failure;
1561 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1562 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1563 err = -EAGAIN;
1564 if (!timeo)
1565 goto failure;
1566 if (signal_pending(current))
1567 goto interrupted;
1568 timeo = sock_wait_for_wmem(sk, timeo);
1571 skb_set_owner_w(skb, sk);
1572 return skb;
1574 interrupted:
1575 err = sock_intr_errno(timeo);
1576 failure:
1577 *errcode = err;
1578 return NULL;
1580 EXPORT_SYMBOL(sock_alloc_send_pskb);
1582 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1583 int noblock, int *errcode)
1585 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1587 EXPORT_SYMBOL(sock_alloc_send_skb);
1589 static void __lock_sock(struct sock *sk)
1590 __releases(&sk->sk_lock.slock)
1591 __acquires(&sk->sk_lock.slock)
1593 DEFINE_WAIT(wait);
1595 for (;;) {
1596 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1597 TASK_UNINTERRUPTIBLE);
1598 spin_unlock_bh(&sk->sk_lock.slock);
1599 schedule();
1600 spin_lock_bh(&sk->sk_lock.slock);
1601 if (!sock_owned_by_user(sk))
1602 break;
1604 finish_wait(&sk->sk_lock.wq, &wait);
1607 static void __release_sock(struct sock *sk)
1608 __releases(&sk->sk_lock.slock)
1609 __acquires(&sk->sk_lock.slock)
1611 struct sk_buff *skb = sk->sk_backlog.head;
1613 do {
1614 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1615 bh_unlock_sock(sk);
1617 do {
1618 struct sk_buff *next = skb->next;
1620 WARN_ON_ONCE(skb_dst_is_noref(skb));
1621 skb->next = NULL;
1622 sk_backlog_rcv(sk, skb);
1625 * We are in process context here with softirqs
1626 * disabled, use cond_resched_softirq() to preempt.
1627 * This is safe to do because we've taken the backlog
1628 * queue private:
1630 cond_resched_softirq();
1632 skb = next;
1633 } while (skb != NULL);
1635 bh_lock_sock(sk);
1636 } while ((skb = sk->sk_backlog.head) != NULL);
1639 * Doing the zeroing here guarantee we can not loop forever
1640 * while a wild producer attempts to flood us.
1642 sk->sk_backlog.len = 0;
1646 * sk_wait_data - wait for data to arrive at sk_receive_queue
1647 * @sk: sock to wait on
1648 * @timeo: for how long
1650 * Now socket state including sk->sk_err is changed only under lock,
1651 * hence we may omit checks after joining wait queue.
1652 * We check receive queue before schedule() only as optimization;
1653 * it is very likely that release_sock() added new data.
1655 int sk_wait_data(struct sock *sk, long *timeo)
1657 int rc;
1658 DEFINE_WAIT(wait);
1660 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1661 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1662 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1663 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1664 finish_wait(sk_sleep(sk), &wait);
1665 return rc;
1667 EXPORT_SYMBOL(sk_wait_data);
1670 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1671 * @sk: socket
1672 * @size: memory size to allocate
1673 * @kind: allocation type
1675 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1676 * rmem allocation. This function assumes that protocols which have
1677 * memory_pressure use sk_wmem_queued as write buffer accounting.
1679 int __sk_mem_schedule(struct sock *sk, int size, int kind)
1681 struct proto *prot = sk->sk_prot;
1682 int amt = sk_mem_pages(size);
1683 long allocated;
1685 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1686 allocated = atomic_long_add_return(amt, prot->memory_allocated);
1688 /* Under limit. */
1689 if (allocated <= prot->sysctl_mem[0]) {
1690 if (prot->memory_pressure && *prot->memory_pressure)
1691 *prot->memory_pressure = 0;
1692 return 1;
1695 /* Under pressure. */
1696 if (allocated > prot->sysctl_mem[1])
1697 if (prot->enter_memory_pressure)
1698 prot->enter_memory_pressure(sk);
1700 /* Over hard limit. */
1701 if (allocated > prot->sysctl_mem[2])
1702 goto suppress_allocation;
1704 /* guarantee minimum buffer size under pressure */
1705 if (kind == SK_MEM_RECV) {
1706 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1707 return 1;
1708 } else { /* SK_MEM_SEND */
1709 if (sk->sk_type == SOCK_STREAM) {
1710 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1711 return 1;
1712 } else if (atomic_read(&sk->sk_wmem_alloc) <
1713 prot->sysctl_wmem[0])
1714 return 1;
1717 if (prot->memory_pressure) {
1718 int alloc;
1720 if (!*prot->memory_pressure)
1721 return 1;
1722 alloc = percpu_counter_read_positive(prot->sockets_allocated);
1723 if (prot->sysctl_mem[2] > alloc *
1724 sk_mem_pages(sk->sk_wmem_queued +
1725 atomic_read(&sk->sk_rmem_alloc) +
1726 sk->sk_forward_alloc))
1727 return 1;
1730 suppress_allocation:
1732 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1733 sk_stream_moderate_sndbuf(sk);
1735 /* Fail only if socket is _under_ its sndbuf.
1736 * In this case we cannot block, so that we have to fail.
1738 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1739 return 1;
1742 trace_sock_exceed_buf_limit(sk, prot, allocated);
1744 /* Alas. Undo changes. */
1745 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1746 atomic_long_sub(amt, prot->memory_allocated);
1747 return 0;
1749 EXPORT_SYMBOL(__sk_mem_schedule);
1752 * __sk_reclaim - reclaim memory_allocated
1753 * @sk: socket
1755 void __sk_mem_reclaim(struct sock *sk)
1757 struct proto *prot = sk->sk_prot;
1759 atomic_long_sub(sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT,
1760 prot->memory_allocated);
1761 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1763 if (prot->memory_pressure && *prot->memory_pressure &&
1764 (atomic_long_read(prot->memory_allocated) < prot->sysctl_mem[0]))
1765 *prot->memory_pressure = 0;
1767 EXPORT_SYMBOL(__sk_mem_reclaim);
1771 * Set of default routines for initialising struct proto_ops when
1772 * the protocol does not support a particular function. In certain
1773 * cases where it makes no sense for a protocol to have a "do nothing"
1774 * function, some default processing is provided.
1777 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1779 return -EOPNOTSUPP;
1781 EXPORT_SYMBOL(sock_no_bind);
1783 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1784 int len, int flags)
1786 return -EOPNOTSUPP;
1788 EXPORT_SYMBOL(sock_no_connect);
1790 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1792 return -EOPNOTSUPP;
1794 EXPORT_SYMBOL(sock_no_socketpair);
1796 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1798 return -EOPNOTSUPP;
1800 EXPORT_SYMBOL(sock_no_accept);
1802 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1803 int *len, int peer)
1805 return -EOPNOTSUPP;
1807 EXPORT_SYMBOL(sock_no_getname);
1809 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1811 return 0;
1813 EXPORT_SYMBOL(sock_no_poll);
1815 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1817 return -EOPNOTSUPP;
1819 EXPORT_SYMBOL(sock_no_ioctl);
1821 int sock_no_listen(struct socket *sock, int backlog)
1823 return -EOPNOTSUPP;
1825 EXPORT_SYMBOL(sock_no_listen);
1827 int sock_no_shutdown(struct socket *sock, int how)
1829 return -EOPNOTSUPP;
1831 EXPORT_SYMBOL(sock_no_shutdown);
1833 int sock_no_setsockopt(struct socket *sock, int level, int optname,
1834 char __user *optval, unsigned int optlen)
1836 return -EOPNOTSUPP;
1838 EXPORT_SYMBOL(sock_no_setsockopt);
1840 int sock_no_getsockopt(struct socket *sock, int level, int optname,
1841 char __user *optval, int __user *optlen)
1843 return -EOPNOTSUPP;
1845 EXPORT_SYMBOL(sock_no_getsockopt);
1847 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1848 size_t len)
1850 return -EOPNOTSUPP;
1852 EXPORT_SYMBOL(sock_no_sendmsg);
1854 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1855 size_t len, int flags)
1857 return -EOPNOTSUPP;
1859 EXPORT_SYMBOL(sock_no_recvmsg);
1861 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1863 /* Mirror missing mmap method error code */
1864 return -ENODEV;
1866 EXPORT_SYMBOL(sock_no_mmap);
1868 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
1870 ssize_t res;
1871 struct msghdr msg = {.msg_flags = flags};
1872 struct kvec iov;
1873 char *kaddr = kmap(page);
1874 iov.iov_base = kaddr + offset;
1875 iov.iov_len = size;
1876 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
1877 kunmap(page);
1878 return res;
1880 EXPORT_SYMBOL(sock_no_sendpage);
1883 * Default Socket Callbacks
1886 static void sock_def_wakeup(struct sock *sk)
1888 struct socket_wq *wq;
1890 rcu_read_lock();
1891 wq = rcu_dereference(sk->sk_wq);
1892 if (wq_has_sleeper(wq))
1893 wake_up_interruptible_all(&wq->wait);
1894 rcu_read_unlock();
1897 static void sock_def_error_report(struct sock *sk)
1899 struct socket_wq *wq;
1901 rcu_read_lock();
1902 wq = rcu_dereference(sk->sk_wq);
1903 if (wq_has_sleeper(wq))
1904 wake_up_interruptible_poll(&wq->wait, POLLERR);
1905 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
1906 rcu_read_unlock();
1909 static void sock_def_readable(struct sock *sk, int len)
1911 struct socket_wq *wq;
1913 rcu_read_lock();
1914 wq = rcu_dereference(sk->sk_wq);
1915 if (wq_has_sleeper(wq))
1916 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
1917 POLLRDNORM | POLLRDBAND);
1918 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
1919 rcu_read_unlock();
1922 static void sock_def_write_space(struct sock *sk)
1924 struct socket_wq *wq;
1926 rcu_read_lock();
1928 /* Do not wake up a writer until he can make "significant"
1929 * progress. --DaveM
1931 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
1932 wq = rcu_dereference(sk->sk_wq);
1933 if (wq_has_sleeper(wq))
1934 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
1935 POLLWRNORM | POLLWRBAND);
1937 /* Should agree with poll, otherwise some programs break */
1938 if (sock_writeable(sk))
1939 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
1942 rcu_read_unlock();
1945 static void sock_def_destruct(struct sock *sk)
1947 kfree(sk->sk_protinfo);
1950 void sk_send_sigurg(struct sock *sk)
1952 if (sk->sk_socket && sk->sk_socket->file)
1953 if (send_sigurg(&sk->sk_socket->file->f_owner))
1954 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
1956 EXPORT_SYMBOL(sk_send_sigurg);
1958 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1959 unsigned long expires)
1961 if (!mod_timer(timer, expires))
1962 sock_hold(sk);
1964 EXPORT_SYMBOL(sk_reset_timer);
1966 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
1968 if (timer_pending(timer) && del_timer(timer))
1969 __sock_put(sk);
1971 EXPORT_SYMBOL(sk_stop_timer);
1973 void sock_init_data(struct socket *sock, struct sock *sk)
1975 skb_queue_head_init(&sk->sk_receive_queue);
1976 skb_queue_head_init(&sk->sk_write_queue);
1977 skb_queue_head_init(&sk->sk_error_queue);
1978 #ifdef CONFIG_NET_DMA
1979 skb_queue_head_init(&sk->sk_async_wait_queue);
1980 #endif
1982 sk->sk_send_head = NULL;
1984 init_timer(&sk->sk_timer);
1986 sk->sk_allocation = GFP_KERNEL;
1987 sk->sk_rcvbuf = sysctl_rmem_default;
1988 sk->sk_sndbuf = sysctl_wmem_default;
1989 sk->sk_state = TCP_CLOSE;
1990 sk_set_socket(sk, sock);
1992 sock_set_flag(sk, SOCK_ZAPPED);
1994 if (sock) {
1995 sk->sk_type = sock->type;
1996 sk->sk_wq = sock->wq;
1997 sock->sk = sk;
1998 } else
1999 sk->sk_wq = NULL;
2001 spin_lock_init(&sk->sk_dst_lock);
2002 rwlock_init(&sk->sk_callback_lock);
2003 lockdep_set_class_and_name(&sk->sk_callback_lock,
2004 af_callback_keys + sk->sk_family,
2005 af_family_clock_key_strings[sk->sk_family]);
2007 sk->sk_state_change = sock_def_wakeup;
2008 sk->sk_data_ready = sock_def_readable;
2009 sk->sk_write_space = sock_def_write_space;
2010 sk->sk_error_report = sock_def_error_report;
2011 sk->sk_destruct = sock_def_destruct;
2013 sk->sk_sndmsg_page = NULL;
2014 sk->sk_sndmsg_off = 0;
2016 sk->sk_peer_pid = NULL;
2017 sk->sk_peer_cred = NULL;
2018 sk->sk_write_pending = 0;
2019 sk->sk_rcvlowat = 1;
2020 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2021 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2023 sk->sk_stamp = ktime_set(-1L, 0);
2026 * Before updating sk_refcnt, we must commit prior changes to memory
2027 * (Documentation/RCU/rculist_nulls.txt for details)
2029 smp_wmb();
2030 atomic_set(&sk->sk_refcnt, 1);
2031 atomic_set(&sk->sk_drops, 0);
2033 EXPORT_SYMBOL(sock_init_data);
2035 void lock_sock_nested(struct sock *sk, int subclass)
2037 might_sleep();
2038 spin_lock_bh(&sk->sk_lock.slock);
2039 if (sk->sk_lock.owned)
2040 __lock_sock(sk);
2041 sk->sk_lock.owned = 1;
2042 spin_unlock(&sk->sk_lock.slock);
2044 * The sk_lock has mutex_lock() semantics here:
2046 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2047 local_bh_enable();
2049 EXPORT_SYMBOL(lock_sock_nested);
2051 void release_sock(struct sock *sk)
2054 * The sk_lock has mutex_unlock() semantics:
2056 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2058 spin_lock_bh(&sk->sk_lock.slock);
2059 if (sk->sk_backlog.tail)
2060 __release_sock(sk);
2061 sk->sk_lock.owned = 0;
2062 if (waitqueue_active(&sk->sk_lock.wq))
2063 wake_up(&sk->sk_lock.wq);
2064 spin_unlock_bh(&sk->sk_lock.slock);
2066 EXPORT_SYMBOL(release_sock);
2069 * lock_sock_fast - fast version of lock_sock
2070 * @sk: socket
2072 * This version should be used for very small section, where process wont block
2073 * return false if fast path is taken
2074 * sk_lock.slock locked, owned = 0, BH disabled
2075 * return true if slow path is taken
2076 * sk_lock.slock unlocked, owned = 1, BH enabled
2078 bool lock_sock_fast(struct sock *sk)
2080 might_sleep();
2081 spin_lock_bh(&sk->sk_lock.slock);
2083 if (!sk->sk_lock.owned)
2085 * Note : We must disable BH
2087 return false;
2089 __lock_sock(sk);
2090 sk->sk_lock.owned = 1;
2091 spin_unlock(&sk->sk_lock.slock);
2093 * The sk_lock has mutex_lock() semantics here:
2095 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2096 local_bh_enable();
2097 return true;
2099 EXPORT_SYMBOL(lock_sock_fast);
2101 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2103 struct timeval tv;
2104 if (!sock_flag(sk, SOCK_TIMESTAMP))
2105 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2106 tv = ktime_to_timeval(sk->sk_stamp);
2107 if (tv.tv_sec == -1)
2108 return -ENOENT;
2109 if (tv.tv_sec == 0) {
2110 sk->sk_stamp = ktime_get_real();
2111 tv = ktime_to_timeval(sk->sk_stamp);
2113 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2115 EXPORT_SYMBOL(sock_get_timestamp);
2117 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2119 struct timespec ts;
2120 if (!sock_flag(sk, SOCK_TIMESTAMP))
2121 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2122 ts = ktime_to_timespec(sk->sk_stamp);
2123 if (ts.tv_sec == -1)
2124 return -ENOENT;
2125 if (ts.tv_sec == 0) {
2126 sk->sk_stamp = ktime_get_real();
2127 ts = ktime_to_timespec(sk->sk_stamp);
2129 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2131 EXPORT_SYMBOL(sock_get_timestampns);
2133 void sock_enable_timestamp(struct sock *sk, int flag)
2135 if (!sock_flag(sk, flag)) {
2136 sock_set_flag(sk, flag);
2138 * we just set one of the two flags which require net
2139 * time stamping, but time stamping might have been on
2140 * already because of the other one
2142 if (!sock_flag(sk,
2143 flag == SOCK_TIMESTAMP ?
2144 SOCK_TIMESTAMPING_RX_SOFTWARE :
2145 SOCK_TIMESTAMP))
2146 net_enable_timestamp();
2151 * Get a socket option on an socket.
2153 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2154 * asynchronous errors should be reported by getsockopt. We assume
2155 * this means if you specify SO_ERROR (otherwise whats the point of it).
2157 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2158 char __user *optval, int __user *optlen)
2160 struct sock *sk = sock->sk;
2162 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2164 EXPORT_SYMBOL(sock_common_getsockopt);
2166 #ifdef CONFIG_COMPAT
2167 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2168 char __user *optval, int __user *optlen)
2170 struct sock *sk = sock->sk;
2172 if (sk->sk_prot->compat_getsockopt != NULL)
2173 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2174 optval, optlen);
2175 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2177 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2178 #endif
2180 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2181 struct msghdr *msg, size_t size, int flags)
2183 struct sock *sk = sock->sk;
2184 int addr_len = 0;
2185 int err;
2187 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2188 flags & ~MSG_DONTWAIT, &addr_len);
2189 if (err >= 0)
2190 msg->msg_namelen = addr_len;
2191 return err;
2193 EXPORT_SYMBOL(sock_common_recvmsg);
2196 * Set socket options on an inet socket.
2198 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2199 char __user *optval, unsigned int optlen)
2201 struct sock *sk = sock->sk;
2203 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2205 EXPORT_SYMBOL(sock_common_setsockopt);
2207 #ifdef CONFIG_COMPAT
2208 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2209 char __user *optval, unsigned int optlen)
2211 struct sock *sk = sock->sk;
2213 if (sk->sk_prot->compat_setsockopt != NULL)
2214 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2215 optval, optlen);
2216 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2218 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2219 #endif
2221 void sk_common_release(struct sock *sk)
2223 if (sk->sk_prot->destroy)
2224 sk->sk_prot->destroy(sk);
2227 * Observation: when sock_common_release is called, processes have
2228 * no access to socket. But net still has.
2229 * Step one, detach it from networking:
2231 * A. Remove from hash tables.
2234 sk->sk_prot->unhash(sk);
2237 * In this point socket cannot receive new packets, but it is possible
2238 * that some packets are in flight because some CPU runs receiver and
2239 * did hash table lookup before we unhashed socket. They will achieve
2240 * receive queue and will be purged by socket destructor.
2242 * Also we still have packets pending on receive queue and probably,
2243 * our own packets waiting in device queues. sock_destroy will drain
2244 * receive queue, but transmitted packets will delay socket destruction
2245 * until the last reference will be released.
2248 sock_orphan(sk);
2250 xfrm_sk_free_policy(sk);
2252 sk_refcnt_debug_release(sk);
2253 sock_put(sk);
2255 EXPORT_SYMBOL(sk_common_release);
2257 static DEFINE_RWLOCK(proto_list_lock);
2258 static LIST_HEAD(proto_list);
2260 #ifdef CONFIG_PROC_FS
2261 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
2262 struct prot_inuse {
2263 int val[PROTO_INUSE_NR];
2266 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2268 #ifdef CONFIG_NET_NS
2269 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2271 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2273 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2275 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2277 int cpu, idx = prot->inuse_idx;
2278 int res = 0;
2280 for_each_possible_cpu(cpu)
2281 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2283 return res >= 0 ? res : 0;
2285 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2287 static int __net_init sock_inuse_init_net(struct net *net)
2289 net->core.inuse = alloc_percpu(struct prot_inuse);
2290 return net->core.inuse ? 0 : -ENOMEM;
2293 static void __net_exit sock_inuse_exit_net(struct net *net)
2295 free_percpu(net->core.inuse);
2298 static struct pernet_operations net_inuse_ops = {
2299 .init = sock_inuse_init_net,
2300 .exit = sock_inuse_exit_net,
2303 static __init int net_inuse_init(void)
2305 if (register_pernet_subsys(&net_inuse_ops))
2306 panic("Cannot initialize net inuse counters");
2308 return 0;
2311 core_initcall(net_inuse_init);
2312 #else
2313 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2315 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2317 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2319 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2321 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2323 int cpu, idx = prot->inuse_idx;
2324 int res = 0;
2326 for_each_possible_cpu(cpu)
2327 res += per_cpu(prot_inuse, cpu).val[idx];
2329 return res >= 0 ? res : 0;
2331 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2332 #endif
2334 static void assign_proto_idx(struct proto *prot)
2336 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2338 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2339 printk(KERN_ERR "PROTO_INUSE_NR exhausted\n");
2340 return;
2343 set_bit(prot->inuse_idx, proto_inuse_idx);
2346 static void release_proto_idx(struct proto *prot)
2348 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2349 clear_bit(prot->inuse_idx, proto_inuse_idx);
2351 #else
2352 static inline void assign_proto_idx(struct proto *prot)
2356 static inline void release_proto_idx(struct proto *prot)
2359 #endif
2361 int proto_register(struct proto *prot, int alloc_slab)
2363 if (alloc_slab) {
2364 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2365 SLAB_HWCACHE_ALIGN | prot->slab_flags,
2366 NULL);
2368 if (prot->slab == NULL) {
2369 printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n",
2370 prot->name);
2371 goto out;
2374 if (prot->rsk_prot != NULL) {
2375 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2376 if (prot->rsk_prot->slab_name == NULL)
2377 goto out_free_sock_slab;
2379 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2380 prot->rsk_prot->obj_size, 0,
2381 SLAB_HWCACHE_ALIGN, NULL);
2383 if (prot->rsk_prot->slab == NULL) {
2384 printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n",
2385 prot->name);
2386 goto out_free_request_sock_slab_name;
2390 if (prot->twsk_prot != NULL) {
2391 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2393 if (prot->twsk_prot->twsk_slab_name == NULL)
2394 goto out_free_request_sock_slab;
2396 prot->twsk_prot->twsk_slab =
2397 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2398 prot->twsk_prot->twsk_obj_size,
2400 SLAB_HWCACHE_ALIGN |
2401 prot->slab_flags,
2402 NULL);
2403 if (prot->twsk_prot->twsk_slab == NULL)
2404 goto out_free_timewait_sock_slab_name;
2408 write_lock(&proto_list_lock);
2409 list_add(&prot->node, &proto_list);
2410 assign_proto_idx(prot);
2411 write_unlock(&proto_list_lock);
2412 return 0;
2414 out_free_timewait_sock_slab_name:
2415 kfree(prot->twsk_prot->twsk_slab_name);
2416 out_free_request_sock_slab:
2417 if (prot->rsk_prot && prot->rsk_prot->slab) {
2418 kmem_cache_destroy(prot->rsk_prot->slab);
2419 prot->rsk_prot->slab = NULL;
2421 out_free_request_sock_slab_name:
2422 if (prot->rsk_prot)
2423 kfree(prot->rsk_prot->slab_name);
2424 out_free_sock_slab:
2425 kmem_cache_destroy(prot->slab);
2426 prot->slab = NULL;
2427 out:
2428 return -ENOBUFS;
2430 EXPORT_SYMBOL(proto_register);
2432 void proto_unregister(struct proto *prot)
2434 write_lock(&proto_list_lock);
2435 release_proto_idx(prot);
2436 list_del(&prot->node);
2437 write_unlock(&proto_list_lock);
2439 if (prot->slab != NULL) {
2440 kmem_cache_destroy(prot->slab);
2441 prot->slab = NULL;
2444 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2445 kmem_cache_destroy(prot->rsk_prot->slab);
2446 kfree(prot->rsk_prot->slab_name);
2447 prot->rsk_prot->slab = NULL;
2450 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2451 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2452 kfree(prot->twsk_prot->twsk_slab_name);
2453 prot->twsk_prot->twsk_slab = NULL;
2456 EXPORT_SYMBOL(proto_unregister);
2458 #ifdef CONFIG_PROC_FS
2459 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2460 __acquires(proto_list_lock)
2462 read_lock(&proto_list_lock);
2463 return seq_list_start_head(&proto_list, *pos);
2466 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2468 return seq_list_next(v, &proto_list, pos);
2471 static void proto_seq_stop(struct seq_file *seq, void *v)
2472 __releases(proto_list_lock)
2474 read_unlock(&proto_list_lock);
2477 static char proto_method_implemented(const void *method)
2479 return method == NULL ? 'n' : 'y';
2482 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2484 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
2485 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2486 proto->name,
2487 proto->obj_size,
2488 sock_prot_inuse_get(seq_file_net(seq), proto),
2489 proto->memory_allocated != NULL ? atomic_long_read(proto->memory_allocated) : -1L,
2490 proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI",
2491 proto->max_header,
2492 proto->slab == NULL ? "no" : "yes",
2493 module_name(proto->owner),
2494 proto_method_implemented(proto->close),
2495 proto_method_implemented(proto->connect),
2496 proto_method_implemented(proto->disconnect),
2497 proto_method_implemented(proto->accept),
2498 proto_method_implemented(proto->ioctl),
2499 proto_method_implemented(proto->init),
2500 proto_method_implemented(proto->destroy),
2501 proto_method_implemented(proto->shutdown),
2502 proto_method_implemented(proto->setsockopt),
2503 proto_method_implemented(proto->getsockopt),
2504 proto_method_implemented(proto->sendmsg),
2505 proto_method_implemented(proto->recvmsg),
2506 proto_method_implemented(proto->sendpage),
2507 proto_method_implemented(proto->bind),
2508 proto_method_implemented(proto->backlog_rcv),
2509 proto_method_implemented(proto->hash),
2510 proto_method_implemented(proto->unhash),
2511 proto_method_implemented(proto->get_port),
2512 proto_method_implemented(proto->enter_memory_pressure));
2515 static int proto_seq_show(struct seq_file *seq, void *v)
2517 if (v == &proto_list)
2518 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2519 "protocol",
2520 "size",
2521 "sockets",
2522 "memory",
2523 "press",
2524 "maxhdr",
2525 "slab",
2526 "module",
2527 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2528 else
2529 proto_seq_printf(seq, list_entry(v, struct proto, node));
2530 return 0;
2533 static const struct seq_operations proto_seq_ops = {
2534 .start = proto_seq_start,
2535 .next = proto_seq_next,
2536 .stop = proto_seq_stop,
2537 .show = proto_seq_show,
2540 static int proto_seq_open(struct inode *inode, struct file *file)
2542 return seq_open_net(inode, file, &proto_seq_ops,
2543 sizeof(struct seq_net_private));
2546 static const struct file_operations proto_seq_fops = {
2547 .owner = THIS_MODULE,
2548 .open = proto_seq_open,
2549 .read = seq_read,
2550 .llseek = seq_lseek,
2551 .release = seq_release_net,
2554 static __net_init int proto_init_net(struct net *net)
2556 if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2557 return -ENOMEM;
2559 return 0;
2562 static __net_exit void proto_exit_net(struct net *net)
2564 proc_net_remove(net, "protocols");
2568 static __net_initdata struct pernet_operations proto_net_ops = {
2569 .init = proto_init_net,
2570 .exit = proto_exit_net,
2573 static int __init proto_init(void)
2575 return register_pernet_subsys(&proto_net_ops);
2578 subsys_initcall(proto_init);
2580 #endif /* PROC_FS */