drm: Fix authentication kernel crash
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / core / sock.c
blobb23f174ab84c3b6c72302834d8e13695d22a1c6c
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 SKB_TRUESIZE(256)
211 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
212 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
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 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
292 atomic_inc(&sk->sk_drops);
293 trace_sock_rcvqueue_full(sk, skb);
294 return -ENOMEM;
297 err = sk_filter(sk, skb);
298 if (err)
299 return err;
301 if (!sk_rmem_schedule(sk, skb->truesize)) {
302 atomic_inc(&sk->sk_drops);
303 return -ENOBUFS;
306 skb->dev = NULL;
307 skb_set_owner_r(skb, sk);
309 /* Cache the SKB length before we tack it onto the receive
310 * queue. Once it is added it no longer belongs to us and
311 * may be freed by other threads of control pulling packets
312 * from the queue.
314 skb_len = skb->len;
316 /* we escape from rcu protected region, make sure we dont leak
317 * a norefcounted dst
319 skb_dst_force(skb);
321 spin_lock_irqsave(&list->lock, flags);
322 skb->dropcount = atomic_read(&sk->sk_drops);
323 __skb_queue_tail(list, skb);
324 spin_unlock_irqrestore(&list->lock, flags);
326 if (!sock_flag(sk, SOCK_DEAD))
327 sk->sk_data_ready(sk, skb_len);
328 return 0;
330 EXPORT_SYMBOL(sock_queue_rcv_skb);
332 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
334 int rc = NET_RX_SUCCESS;
336 if (sk_filter(sk, skb))
337 goto discard_and_relse;
339 skb->dev = NULL;
341 if (sk_rcvqueues_full(sk, skb)) {
342 atomic_inc(&sk->sk_drops);
343 goto discard_and_relse;
345 if (nested)
346 bh_lock_sock_nested(sk);
347 else
348 bh_lock_sock(sk);
349 if (!sock_owned_by_user(sk)) {
351 * trylock + unlock semantics:
353 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
355 rc = sk_backlog_rcv(sk, skb);
357 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
358 } else if (sk_add_backlog(sk, skb)) {
359 bh_unlock_sock(sk);
360 atomic_inc(&sk->sk_drops);
361 goto discard_and_relse;
364 bh_unlock_sock(sk);
365 out:
366 sock_put(sk);
367 return rc;
368 discard_and_relse:
369 kfree_skb(skb);
370 goto out;
372 EXPORT_SYMBOL(sk_receive_skb);
374 void sk_reset_txq(struct sock *sk)
376 sk_tx_queue_clear(sk);
378 EXPORT_SYMBOL(sk_reset_txq);
380 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
382 struct dst_entry *dst = __sk_dst_get(sk);
384 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
385 sk_tx_queue_clear(sk);
386 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
387 dst_release(dst);
388 return NULL;
391 return dst;
393 EXPORT_SYMBOL(__sk_dst_check);
395 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
397 struct dst_entry *dst = sk_dst_get(sk);
399 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
400 sk_dst_reset(sk);
401 dst_release(dst);
402 return NULL;
405 return dst;
407 EXPORT_SYMBOL(sk_dst_check);
409 static int sock_bindtodevice(struct sock *sk, char __user *optval, int optlen)
411 int ret = -ENOPROTOOPT;
412 #ifdef CONFIG_NETDEVICES
413 struct net *net = sock_net(sk);
414 char devname[IFNAMSIZ];
415 int index;
417 /* Sorry... */
418 ret = -EPERM;
419 if (!capable(CAP_NET_RAW))
420 goto out;
422 ret = -EINVAL;
423 if (optlen < 0)
424 goto out;
426 /* Bind this socket to a particular device like "eth0",
427 * as specified in the passed interface name. If the
428 * name is "" or the option length is zero the socket
429 * is not bound.
431 if (optlen > IFNAMSIZ - 1)
432 optlen = IFNAMSIZ - 1;
433 memset(devname, 0, sizeof(devname));
435 ret = -EFAULT;
436 if (copy_from_user(devname, optval, optlen))
437 goto out;
439 index = 0;
440 if (devname[0] != '\0') {
441 struct net_device *dev;
443 rcu_read_lock();
444 dev = dev_get_by_name_rcu(net, devname);
445 if (dev)
446 index = dev->ifindex;
447 rcu_read_unlock();
448 ret = -ENODEV;
449 if (!dev)
450 goto out;
453 lock_sock(sk);
454 sk->sk_bound_dev_if = index;
455 sk_dst_reset(sk);
456 release_sock(sk);
458 ret = 0;
460 out:
461 #endif
463 return ret;
466 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
468 if (valbool)
469 sock_set_flag(sk, bit);
470 else
471 sock_reset_flag(sk, bit);
475 * This is meant for all protocols to use and covers goings on
476 * at the socket level. Everything here is generic.
479 int sock_setsockopt(struct socket *sock, int level, int optname,
480 char __user *optval, unsigned int optlen)
482 struct sock *sk = sock->sk;
483 int val;
484 int valbool;
485 struct linger ling;
486 int ret = 0;
489 * Options without arguments
492 if (optname == SO_BINDTODEVICE)
493 return sock_bindtodevice(sk, optval, optlen);
495 if (optlen < sizeof(int))
496 return -EINVAL;
498 if (get_user(val, (int __user *)optval))
499 return -EFAULT;
501 valbool = val ? 1 : 0;
503 lock_sock(sk);
505 switch (optname) {
506 case SO_DEBUG:
507 if (val && !capable(CAP_NET_ADMIN))
508 ret = -EACCES;
509 else
510 sock_valbool_flag(sk, SOCK_DBG, valbool);
511 break;
512 case SO_REUSEADDR:
513 sk->sk_reuse = valbool;
514 break;
515 case SO_TYPE:
516 case SO_PROTOCOL:
517 case SO_DOMAIN:
518 case SO_ERROR:
519 ret = -ENOPROTOOPT;
520 break;
521 case SO_DONTROUTE:
522 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
523 break;
524 case SO_BROADCAST:
525 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
526 break;
527 case SO_SNDBUF:
528 /* Don't error on this BSD doesn't and if you think
529 about it this is right. Otherwise apps have to
530 play 'guess the biggest size' games. RCVBUF/SNDBUF
531 are treated in BSD as hints */
533 if (val > sysctl_wmem_max)
534 val = sysctl_wmem_max;
535 set_sndbuf:
536 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
537 if ((val * 2) < SOCK_MIN_SNDBUF)
538 sk->sk_sndbuf = SOCK_MIN_SNDBUF;
539 else
540 sk->sk_sndbuf = val * 2;
543 * Wake up sending tasks if we
544 * upped the value.
546 sk->sk_write_space(sk);
547 break;
549 case SO_SNDBUFFORCE:
550 if (!capable(CAP_NET_ADMIN)) {
551 ret = -EPERM;
552 break;
554 goto set_sndbuf;
556 case SO_RCVBUF:
557 /* Don't error on this BSD doesn't and if you think
558 about it this is right. Otherwise apps have to
559 play 'guess the biggest size' games. RCVBUF/SNDBUF
560 are treated in BSD as hints */
562 if (val > sysctl_rmem_max)
563 val = sysctl_rmem_max;
564 set_rcvbuf:
565 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
567 * We double it on the way in to account for
568 * "struct sk_buff" etc. overhead. Applications
569 * assume that the SO_RCVBUF setting they make will
570 * allow that much actual data to be received on that
571 * socket.
573 * Applications are unaware that "struct sk_buff" and
574 * other overheads allocate from the receive buffer
575 * during socket buffer allocation.
577 * And after considering the possible alternatives,
578 * returning the value we actually used in getsockopt
579 * is the most desirable behavior.
581 if ((val * 2) < SOCK_MIN_RCVBUF)
582 sk->sk_rcvbuf = SOCK_MIN_RCVBUF;
583 else
584 sk->sk_rcvbuf = val * 2;
585 break;
587 case SO_RCVBUFFORCE:
588 if (!capable(CAP_NET_ADMIN)) {
589 ret = -EPERM;
590 break;
592 goto set_rcvbuf;
594 case SO_KEEPALIVE:
595 #ifdef CONFIG_INET
596 if (sk->sk_protocol == IPPROTO_TCP)
597 tcp_set_keepalive(sk, valbool);
598 #endif
599 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
600 break;
602 case SO_OOBINLINE:
603 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
604 break;
606 case SO_NO_CHECK:
607 sk->sk_no_check = valbool;
608 break;
610 case SO_PRIORITY:
611 if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN))
612 sk->sk_priority = val;
613 else
614 ret = -EPERM;
615 break;
617 case SO_LINGER:
618 if (optlen < sizeof(ling)) {
619 ret = -EINVAL; /* 1003.1g */
620 break;
622 if (copy_from_user(&ling, optval, sizeof(ling))) {
623 ret = -EFAULT;
624 break;
626 if (!ling.l_onoff)
627 sock_reset_flag(sk, SOCK_LINGER);
628 else {
629 #if (BITS_PER_LONG == 32)
630 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
631 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
632 else
633 #endif
634 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
635 sock_set_flag(sk, SOCK_LINGER);
637 break;
639 case SO_BSDCOMPAT:
640 sock_warn_obsolete_bsdism("setsockopt");
641 break;
643 case SO_PASSCRED:
644 if (valbool)
645 set_bit(SOCK_PASSCRED, &sock->flags);
646 else
647 clear_bit(SOCK_PASSCRED, &sock->flags);
648 break;
650 case SO_TIMESTAMP:
651 case SO_TIMESTAMPNS:
652 if (valbool) {
653 if (optname == SO_TIMESTAMP)
654 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
655 else
656 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
657 sock_set_flag(sk, SOCK_RCVTSTAMP);
658 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
659 } else {
660 sock_reset_flag(sk, SOCK_RCVTSTAMP);
661 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
663 break;
665 case SO_TIMESTAMPING:
666 if (val & ~SOF_TIMESTAMPING_MASK) {
667 ret = -EINVAL;
668 break;
670 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE,
671 val & SOF_TIMESTAMPING_TX_HARDWARE);
672 sock_valbool_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE,
673 val & SOF_TIMESTAMPING_TX_SOFTWARE);
674 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE,
675 val & SOF_TIMESTAMPING_RX_HARDWARE);
676 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
677 sock_enable_timestamp(sk,
678 SOCK_TIMESTAMPING_RX_SOFTWARE);
679 else
680 sock_disable_timestamp(sk,
681 SOCK_TIMESTAMPING_RX_SOFTWARE);
682 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SOFTWARE,
683 val & SOF_TIMESTAMPING_SOFTWARE);
684 sock_valbool_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE,
685 val & SOF_TIMESTAMPING_SYS_HARDWARE);
686 sock_valbool_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE,
687 val & SOF_TIMESTAMPING_RAW_HARDWARE);
688 break;
690 case SO_RCVLOWAT:
691 if (val < 0)
692 val = INT_MAX;
693 sk->sk_rcvlowat = val ? : 1;
694 break;
696 case SO_RCVTIMEO:
697 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
698 break;
700 case SO_SNDTIMEO:
701 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
702 break;
704 case SO_ATTACH_FILTER:
705 ret = -EINVAL;
706 if (optlen == sizeof(struct sock_fprog)) {
707 struct sock_fprog fprog;
709 ret = -EFAULT;
710 if (copy_from_user(&fprog, optval, sizeof(fprog)))
711 break;
713 ret = sk_attach_filter(&fprog, sk);
715 break;
717 case SO_DETACH_FILTER:
718 ret = sk_detach_filter(sk);
719 break;
721 case SO_PASSSEC:
722 if (valbool)
723 set_bit(SOCK_PASSSEC, &sock->flags);
724 else
725 clear_bit(SOCK_PASSSEC, &sock->flags);
726 break;
727 case SO_MARK:
728 if (!capable(CAP_NET_ADMIN))
729 ret = -EPERM;
730 else
731 sk->sk_mark = val;
732 break;
734 /* We implement the SO_SNDLOWAT etc to
735 not be settable (1003.1g 5.3) */
736 case SO_RXQ_OVFL:
737 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
738 break;
739 default:
740 ret = -ENOPROTOOPT;
741 break;
743 release_sock(sk);
744 return ret;
746 EXPORT_SYMBOL(sock_setsockopt);
749 void cred_to_ucred(struct pid *pid, const struct cred *cred,
750 struct ucred *ucred)
752 ucred->pid = pid_vnr(pid);
753 ucred->uid = ucred->gid = -1;
754 if (cred) {
755 struct user_namespace *current_ns = current_user_ns();
757 ucred->uid = user_ns_map_uid(current_ns, cred, cred->euid);
758 ucred->gid = user_ns_map_gid(current_ns, cred, cred->egid);
761 EXPORT_SYMBOL_GPL(cred_to_ucred);
763 int sock_getsockopt(struct socket *sock, int level, int optname,
764 char __user *optval, int __user *optlen)
766 struct sock *sk = sock->sk;
768 union {
769 int val;
770 struct linger ling;
771 struct timeval tm;
772 } v;
774 int lv = sizeof(int);
775 int len;
777 if (get_user(len, optlen))
778 return -EFAULT;
779 if (len < 0)
780 return -EINVAL;
782 memset(&v, 0, sizeof(v));
784 switch (optname) {
785 case SO_DEBUG:
786 v.val = sock_flag(sk, SOCK_DBG);
787 break;
789 case SO_DONTROUTE:
790 v.val = sock_flag(sk, SOCK_LOCALROUTE);
791 break;
793 case SO_BROADCAST:
794 v.val = !!sock_flag(sk, SOCK_BROADCAST);
795 break;
797 case SO_SNDBUF:
798 v.val = sk->sk_sndbuf;
799 break;
801 case SO_RCVBUF:
802 v.val = sk->sk_rcvbuf;
803 break;
805 case SO_REUSEADDR:
806 v.val = sk->sk_reuse;
807 break;
809 case SO_KEEPALIVE:
810 v.val = !!sock_flag(sk, SOCK_KEEPOPEN);
811 break;
813 case SO_TYPE:
814 v.val = sk->sk_type;
815 break;
817 case SO_PROTOCOL:
818 v.val = sk->sk_protocol;
819 break;
821 case SO_DOMAIN:
822 v.val = sk->sk_family;
823 break;
825 case SO_ERROR:
826 v.val = -sock_error(sk);
827 if (v.val == 0)
828 v.val = xchg(&sk->sk_err_soft, 0);
829 break;
831 case SO_OOBINLINE:
832 v.val = !!sock_flag(sk, SOCK_URGINLINE);
833 break;
835 case SO_NO_CHECK:
836 v.val = sk->sk_no_check;
837 break;
839 case SO_PRIORITY:
840 v.val = sk->sk_priority;
841 break;
843 case SO_LINGER:
844 lv = sizeof(v.ling);
845 v.ling.l_onoff = !!sock_flag(sk, SOCK_LINGER);
846 v.ling.l_linger = sk->sk_lingertime / HZ;
847 break;
849 case SO_BSDCOMPAT:
850 sock_warn_obsolete_bsdism("getsockopt");
851 break;
853 case SO_TIMESTAMP:
854 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
855 !sock_flag(sk, SOCK_RCVTSTAMPNS);
856 break;
858 case SO_TIMESTAMPNS:
859 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
860 break;
862 case SO_TIMESTAMPING:
863 v.val = 0;
864 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_HARDWARE))
865 v.val |= SOF_TIMESTAMPING_TX_HARDWARE;
866 if (sock_flag(sk, SOCK_TIMESTAMPING_TX_SOFTWARE))
867 v.val |= SOF_TIMESTAMPING_TX_SOFTWARE;
868 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_HARDWARE))
869 v.val |= SOF_TIMESTAMPING_RX_HARDWARE;
870 if (sock_flag(sk, SOCK_TIMESTAMPING_RX_SOFTWARE))
871 v.val |= SOF_TIMESTAMPING_RX_SOFTWARE;
872 if (sock_flag(sk, SOCK_TIMESTAMPING_SOFTWARE))
873 v.val |= SOF_TIMESTAMPING_SOFTWARE;
874 if (sock_flag(sk, SOCK_TIMESTAMPING_SYS_HARDWARE))
875 v.val |= SOF_TIMESTAMPING_SYS_HARDWARE;
876 if (sock_flag(sk, SOCK_TIMESTAMPING_RAW_HARDWARE))
877 v.val |= SOF_TIMESTAMPING_RAW_HARDWARE;
878 break;
880 case SO_RCVTIMEO:
881 lv = sizeof(struct timeval);
882 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
883 v.tm.tv_sec = 0;
884 v.tm.tv_usec = 0;
885 } else {
886 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
887 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
889 break;
891 case SO_SNDTIMEO:
892 lv = sizeof(struct timeval);
893 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
894 v.tm.tv_sec = 0;
895 v.tm.tv_usec = 0;
896 } else {
897 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
898 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
900 break;
902 case SO_RCVLOWAT:
903 v.val = sk->sk_rcvlowat;
904 break;
906 case SO_SNDLOWAT:
907 v.val = 1;
908 break;
910 case SO_PASSCRED:
911 v.val = test_bit(SOCK_PASSCRED, &sock->flags) ? 1 : 0;
912 break;
914 case SO_PEERCRED:
916 struct ucred peercred;
917 if (len > sizeof(peercred))
918 len = sizeof(peercred);
919 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
920 if (copy_to_user(optval, &peercred, len))
921 return -EFAULT;
922 goto lenout;
925 case SO_PEERNAME:
927 char address[128];
929 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
930 return -ENOTCONN;
931 if (lv < len)
932 return -EINVAL;
933 if (copy_to_user(optval, address, len))
934 return -EFAULT;
935 goto lenout;
938 /* Dubious BSD thing... Probably nobody even uses it, but
939 * the UNIX standard wants it for whatever reason... -DaveM
941 case SO_ACCEPTCONN:
942 v.val = sk->sk_state == TCP_LISTEN;
943 break;
945 case SO_PASSSEC:
946 v.val = test_bit(SOCK_PASSSEC, &sock->flags) ? 1 : 0;
947 break;
949 case SO_PEERSEC:
950 return security_socket_getpeersec_stream(sock, optval, optlen, len);
952 case SO_MARK:
953 v.val = sk->sk_mark;
954 break;
956 case SO_RXQ_OVFL:
957 v.val = !!sock_flag(sk, SOCK_RXQ_OVFL);
958 break;
960 default:
961 return -ENOPROTOOPT;
964 if (len > lv)
965 len = lv;
966 if (copy_to_user(optval, &v, len))
967 return -EFAULT;
968 lenout:
969 if (put_user(len, optlen))
970 return -EFAULT;
971 return 0;
975 * Initialize an sk_lock.
977 * (We also register the sk_lock with the lock validator.)
979 static inline void sock_lock_init(struct sock *sk)
981 sock_lock_init_class_and_name(sk,
982 af_family_slock_key_strings[sk->sk_family],
983 af_family_slock_keys + sk->sk_family,
984 af_family_key_strings[sk->sk_family],
985 af_family_keys + sk->sk_family);
989 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
990 * even temporarly, because of RCU lookups. sk_node should also be left as is.
991 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
993 static void sock_copy(struct sock *nsk, const struct sock *osk)
995 #ifdef CONFIG_SECURITY_NETWORK
996 void *sptr = nsk->sk_security;
997 #endif
998 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1000 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1001 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1003 #ifdef CONFIG_SECURITY_NETWORK
1004 nsk->sk_security = sptr;
1005 security_sk_clone(osk, nsk);
1006 #endif
1010 * caches using SLAB_DESTROY_BY_RCU should let .next pointer from nulls nodes
1011 * un-modified. Special care is taken when initializing object to zero.
1013 static inline void sk_prot_clear_nulls(struct sock *sk, int size)
1015 if (offsetof(struct sock, sk_node.next) != 0)
1016 memset(sk, 0, offsetof(struct sock, sk_node.next));
1017 memset(&sk->sk_node.pprev, 0,
1018 size - offsetof(struct sock, sk_node.pprev));
1021 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1023 unsigned long nulls1, nulls2;
1025 nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1026 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1027 if (nulls1 > nulls2)
1028 swap(nulls1, nulls2);
1030 if (nulls1 != 0)
1031 memset((char *)sk, 0, nulls1);
1032 memset((char *)sk + nulls1 + sizeof(void *), 0,
1033 nulls2 - nulls1 - sizeof(void *));
1034 memset((char *)sk + nulls2 + sizeof(void *), 0,
1035 size - nulls2 - sizeof(void *));
1037 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1039 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1040 int family)
1042 struct sock *sk;
1043 struct kmem_cache *slab;
1045 slab = prot->slab;
1046 if (slab != NULL) {
1047 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1048 if (!sk)
1049 return sk;
1050 if (priority & __GFP_ZERO) {
1051 if (prot->clear_sk)
1052 prot->clear_sk(sk, prot->obj_size);
1053 else
1054 sk_prot_clear_nulls(sk, prot->obj_size);
1056 } else
1057 sk = kmalloc(prot->obj_size, priority);
1059 if (sk != NULL) {
1060 kmemcheck_annotate_bitfield(sk, flags);
1062 if (security_sk_alloc(sk, family, priority))
1063 goto out_free;
1065 if (!try_module_get(prot->owner))
1066 goto out_free_sec;
1067 sk_tx_queue_clear(sk);
1070 return sk;
1072 out_free_sec:
1073 security_sk_free(sk);
1074 out_free:
1075 if (slab != NULL)
1076 kmem_cache_free(slab, sk);
1077 else
1078 kfree(sk);
1079 return NULL;
1082 static void sk_prot_free(struct proto *prot, struct sock *sk)
1084 struct kmem_cache *slab;
1085 struct module *owner;
1087 owner = prot->owner;
1088 slab = prot->slab;
1090 security_sk_free(sk);
1091 if (slab != NULL)
1092 kmem_cache_free(slab, sk);
1093 else
1094 kfree(sk);
1095 module_put(owner);
1098 #ifdef CONFIG_CGROUPS
1099 void sock_update_classid(struct sock *sk)
1101 u32 classid;
1103 rcu_read_lock(); /* doing current task, which cannot vanish. */
1104 classid = task_cls_classid(current);
1105 rcu_read_unlock();
1106 if (classid && classid != sk->sk_classid)
1107 sk->sk_classid = classid;
1109 EXPORT_SYMBOL(sock_update_classid);
1110 #endif
1113 * sk_alloc - All socket objects are allocated here
1114 * @net: the applicable net namespace
1115 * @family: protocol family
1116 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1117 * @prot: struct proto associated with this new sock instance
1119 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1120 struct proto *prot)
1122 struct sock *sk;
1124 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1125 if (sk) {
1126 sk->sk_family = family;
1128 * See comment in struct sock definition to understand
1129 * why we need sk_prot_creator -acme
1131 sk->sk_prot = sk->sk_prot_creator = prot;
1132 sock_lock_init(sk);
1133 sock_net_set(sk, get_net(net));
1134 atomic_set(&sk->sk_wmem_alloc, 1);
1136 sock_update_classid(sk);
1139 return sk;
1141 EXPORT_SYMBOL(sk_alloc);
1143 static void __sk_free(struct sock *sk)
1145 struct sk_filter *filter;
1147 if (sk->sk_destruct)
1148 sk->sk_destruct(sk);
1150 filter = rcu_dereference_check(sk->sk_filter,
1151 atomic_read(&sk->sk_wmem_alloc) == 0);
1152 if (filter) {
1153 sk_filter_uncharge(sk, filter);
1154 RCU_INIT_POINTER(sk->sk_filter, NULL);
1157 sock_disable_timestamp(sk, SOCK_TIMESTAMP);
1158 sock_disable_timestamp(sk, SOCK_TIMESTAMPING_RX_SOFTWARE);
1160 if (atomic_read(&sk->sk_omem_alloc))
1161 printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n",
1162 __func__, atomic_read(&sk->sk_omem_alloc));
1164 if (sk->sk_peer_cred)
1165 put_cred(sk->sk_peer_cred);
1166 put_pid(sk->sk_peer_pid);
1167 put_net(sock_net(sk));
1168 sk_prot_free(sk->sk_prot_creator, sk);
1171 void sk_free(struct sock *sk)
1174 * We subtract one from sk_wmem_alloc and can know if
1175 * some packets are still in some tx queue.
1176 * If not null, sock_wfree() will call __sk_free(sk) later
1178 if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1179 __sk_free(sk);
1181 EXPORT_SYMBOL(sk_free);
1184 * Last sock_put should drop reference to sk->sk_net. It has already
1185 * been dropped in sk_change_net. Taking reference to stopping namespace
1186 * is not an option.
1187 * Take reference to a socket to remove it from hash _alive_ and after that
1188 * destroy it in the context of init_net.
1190 void sk_release_kernel(struct sock *sk)
1192 if (sk == NULL || sk->sk_socket == NULL)
1193 return;
1195 sock_hold(sk);
1196 sock_release(sk->sk_socket);
1197 release_net(sock_net(sk));
1198 sock_net_set(sk, get_net(&init_net));
1199 sock_put(sk);
1201 EXPORT_SYMBOL(sk_release_kernel);
1203 struct sock *sk_clone(const struct sock *sk, const gfp_t priority)
1205 struct sock *newsk;
1207 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1208 if (newsk != NULL) {
1209 struct sk_filter *filter;
1211 sock_copy(newsk, sk);
1213 /* SANITY */
1214 get_net(sock_net(newsk));
1215 sk_node_init(&newsk->sk_node);
1216 sock_lock_init(newsk);
1217 bh_lock_sock(newsk);
1218 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1219 newsk->sk_backlog.len = 0;
1221 atomic_set(&newsk->sk_rmem_alloc, 0);
1223 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1225 atomic_set(&newsk->sk_wmem_alloc, 1);
1226 atomic_set(&newsk->sk_omem_alloc, 0);
1227 skb_queue_head_init(&newsk->sk_receive_queue);
1228 skb_queue_head_init(&newsk->sk_write_queue);
1229 #ifdef CONFIG_NET_DMA
1230 skb_queue_head_init(&newsk->sk_async_wait_queue);
1231 #endif
1233 spin_lock_init(&newsk->sk_dst_lock);
1234 rwlock_init(&newsk->sk_callback_lock);
1235 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1236 af_callback_keys + newsk->sk_family,
1237 af_family_clock_key_strings[newsk->sk_family]);
1239 newsk->sk_dst_cache = NULL;
1240 newsk->sk_wmem_queued = 0;
1241 newsk->sk_forward_alloc = 0;
1242 newsk->sk_send_head = NULL;
1243 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1245 sock_reset_flag(newsk, SOCK_DONE);
1246 skb_queue_head_init(&newsk->sk_error_queue);
1248 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1249 if (filter != NULL)
1250 sk_filter_charge(newsk, filter);
1252 if (unlikely(xfrm_sk_clone_policy(newsk))) {
1253 /* It is still raw copy of parent, so invalidate
1254 * destructor and make plain sk_free() */
1255 newsk->sk_destruct = NULL;
1256 bh_unlock_sock(newsk);
1257 sk_free(newsk);
1258 newsk = NULL;
1259 goto out;
1262 newsk->sk_err = 0;
1263 newsk->sk_priority = 0;
1265 * Before updating sk_refcnt, we must commit prior changes to memory
1266 * (Documentation/RCU/rculist_nulls.txt for details)
1268 smp_wmb();
1269 atomic_set(&newsk->sk_refcnt, 2);
1272 * Increment the counter in the same struct proto as the master
1273 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1274 * is the same as sk->sk_prot->socks, as this field was copied
1275 * with memcpy).
1277 * This _changes_ the previous behaviour, where
1278 * tcp_create_openreq_child always was incrementing the
1279 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1280 * to be taken into account in all callers. -acme
1282 sk_refcnt_debug_inc(newsk);
1283 sk_set_socket(newsk, NULL);
1284 newsk->sk_wq = NULL;
1286 if (newsk->sk_prot->sockets_allocated)
1287 percpu_counter_inc(newsk->sk_prot->sockets_allocated);
1289 if (sock_flag(newsk, SOCK_TIMESTAMP) ||
1290 sock_flag(newsk, SOCK_TIMESTAMPING_RX_SOFTWARE))
1291 net_enable_timestamp();
1293 out:
1294 return newsk;
1296 EXPORT_SYMBOL_GPL(sk_clone);
1298 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1300 __sk_dst_set(sk, dst);
1301 sk->sk_route_caps = dst->dev->features;
1302 if (sk->sk_route_caps & NETIF_F_GSO)
1303 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1304 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1305 if (sk_can_gso(sk)) {
1306 if (dst->header_len) {
1307 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1308 } else {
1309 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1310 sk->sk_gso_max_size = dst->dev->gso_max_size;
1314 EXPORT_SYMBOL_GPL(sk_setup_caps);
1316 void __init sk_init(void)
1318 if (totalram_pages <= 4096) {
1319 sysctl_wmem_max = 32767;
1320 sysctl_rmem_max = 32767;
1321 sysctl_wmem_default = 32767;
1322 sysctl_rmem_default = 32767;
1323 } else if (totalram_pages >= 131072) {
1324 sysctl_wmem_max = 131071;
1325 sysctl_rmem_max = 131071;
1330 * Simple resource managers for sockets.
1335 * Write buffer destructor automatically called from kfree_skb.
1337 void sock_wfree(struct sk_buff *skb)
1339 struct sock *sk = skb->sk;
1340 unsigned int len = skb->truesize;
1342 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1344 * Keep a reference on sk_wmem_alloc, this will be released
1345 * after sk_write_space() call
1347 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1348 sk->sk_write_space(sk);
1349 len = 1;
1352 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1353 * could not do because of in-flight packets
1355 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1356 __sk_free(sk);
1358 EXPORT_SYMBOL(sock_wfree);
1361 * Read buffer destructor automatically called from kfree_skb.
1363 void sock_rfree(struct sk_buff *skb)
1365 struct sock *sk = skb->sk;
1366 unsigned int len = skb->truesize;
1368 atomic_sub(len, &sk->sk_rmem_alloc);
1369 sk_mem_uncharge(sk, len);
1371 EXPORT_SYMBOL(sock_rfree);
1374 int sock_i_uid(struct sock *sk)
1376 int uid;
1378 read_lock_bh(&sk->sk_callback_lock);
1379 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0;
1380 read_unlock_bh(&sk->sk_callback_lock);
1381 return uid;
1383 EXPORT_SYMBOL(sock_i_uid);
1385 unsigned long sock_i_ino(struct sock *sk)
1387 unsigned long ino;
1389 read_lock_bh(&sk->sk_callback_lock);
1390 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1391 read_unlock_bh(&sk->sk_callback_lock);
1392 return ino;
1394 EXPORT_SYMBOL(sock_i_ino);
1397 * Allocate a skb from the socket's send buffer.
1399 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1400 gfp_t priority)
1402 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1403 struct sk_buff *skb = alloc_skb(size, priority);
1404 if (skb) {
1405 skb_set_owner_w(skb, sk);
1406 return skb;
1409 return NULL;
1411 EXPORT_SYMBOL(sock_wmalloc);
1414 * Allocate a skb from the socket's receive buffer.
1416 struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force,
1417 gfp_t priority)
1419 if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
1420 struct sk_buff *skb = alloc_skb(size, priority);
1421 if (skb) {
1422 skb_set_owner_r(skb, sk);
1423 return skb;
1426 return NULL;
1430 * Allocate a memory block from the socket's option memory buffer.
1432 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1434 if ((unsigned)size <= sysctl_optmem_max &&
1435 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1436 void *mem;
1437 /* First do the add, to avoid the race if kmalloc
1438 * might sleep.
1440 atomic_add(size, &sk->sk_omem_alloc);
1441 mem = kmalloc(size, priority);
1442 if (mem)
1443 return mem;
1444 atomic_sub(size, &sk->sk_omem_alloc);
1446 return NULL;
1448 EXPORT_SYMBOL(sock_kmalloc);
1451 * Free an option memory block.
1453 void sock_kfree_s(struct sock *sk, void *mem, int size)
1455 kfree(mem);
1456 atomic_sub(size, &sk->sk_omem_alloc);
1458 EXPORT_SYMBOL(sock_kfree_s);
1460 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1461 I think, these locks should be removed for datagram sockets.
1463 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1465 DEFINE_WAIT(wait);
1467 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1468 for (;;) {
1469 if (!timeo)
1470 break;
1471 if (signal_pending(current))
1472 break;
1473 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1474 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1475 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1476 break;
1477 if (sk->sk_shutdown & SEND_SHUTDOWN)
1478 break;
1479 if (sk->sk_err)
1480 break;
1481 timeo = schedule_timeout(timeo);
1483 finish_wait(sk_sleep(sk), &wait);
1484 return timeo;
1489 * Generic send/receive buffer handlers
1492 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1493 unsigned long data_len, int noblock,
1494 int *errcode)
1496 struct sk_buff *skb;
1497 gfp_t gfp_mask;
1498 long timeo;
1499 int err;
1501 gfp_mask = sk->sk_allocation;
1502 if (gfp_mask & __GFP_WAIT)
1503 gfp_mask |= __GFP_REPEAT;
1505 timeo = sock_sndtimeo(sk, noblock);
1506 while (1) {
1507 err = sock_error(sk);
1508 if (err != 0)
1509 goto failure;
1511 err = -EPIPE;
1512 if (sk->sk_shutdown & SEND_SHUTDOWN)
1513 goto failure;
1515 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1516 skb = alloc_skb(header_len, gfp_mask);
1517 if (skb) {
1518 int npages;
1519 int i;
1521 /* No pages, we're done... */
1522 if (!data_len)
1523 break;
1525 npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1526 skb->truesize += data_len;
1527 skb_shinfo(skb)->nr_frags = npages;
1528 for (i = 0; i < npages; i++) {
1529 struct page *page;
1531 page = alloc_pages(sk->sk_allocation, 0);
1532 if (!page) {
1533 err = -ENOBUFS;
1534 skb_shinfo(skb)->nr_frags = i;
1535 kfree_skb(skb);
1536 goto failure;
1539 __skb_fill_page_desc(skb, i,
1540 page, 0,
1541 (data_len >= PAGE_SIZE ?
1542 PAGE_SIZE :
1543 data_len));
1544 data_len -= PAGE_SIZE;
1547 /* Full success... */
1548 break;
1550 err = -ENOBUFS;
1551 goto failure;
1553 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1554 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1555 err = -EAGAIN;
1556 if (!timeo)
1557 goto failure;
1558 if (signal_pending(current))
1559 goto interrupted;
1560 timeo = sock_wait_for_wmem(sk, timeo);
1563 skb_set_owner_w(skb, sk);
1564 return skb;
1566 interrupted:
1567 err = sock_intr_errno(timeo);
1568 failure:
1569 *errcode = err;
1570 return NULL;
1572 EXPORT_SYMBOL(sock_alloc_send_pskb);
1574 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1575 int noblock, int *errcode)
1577 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode);
1579 EXPORT_SYMBOL(sock_alloc_send_skb);
1581 static void __lock_sock(struct sock *sk)
1582 __releases(&sk->sk_lock.slock)
1583 __acquires(&sk->sk_lock.slock)
1585 DEFINE_WAIT(wait);
1587 for (;;) {
1588 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1589 TASK_UNINTERRUPTIBLE);
1590 spin_unlock_bh(&sk->sk_lock.slock);
1591 schedule();
1592 spin_lock_bh(&sk->sk_lock.slock);
1593 if (!sock_owned_by_user(sk))
1594 break;
1596 finish_wait(&sk->sk_lock.wq, &wait);
1599 static void __release_sock(struct sock *sk)
1600 __releases(&sk->sk_lock.slock)
1601 __acquires(&sk->sk_lock.slock)
1603 struct sk_buff *skb = sk->sk_backlog.head;
1605 do {
1606 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1607 bh_unlock_sock(sk);
1609 do {
1610 struct sk_buff *next = skb->next;
1612 WARN_ON_ONCE(skb_dst_is_noref(skb));
1613 skb->next = NULL;
1614 sk_backlog_rcv(sk, skb);
1617 * We are in process context here with softirqs
1618 * disabled, use cond_resched_softirq() to preempt.
1619 * This is safe to do because we've taken the backlog
1620 * queue private:
1622 cond_resched_softirq();
1624 skb = next;
1625 } while (skb != NULL);
1627 bh_lock_sock(sk);
1628 } while ((skb = sk->sk_backlog.head) != NULL);
1631 * Doing the zeroing here guarantee we can not loop forever
1632 * while a wild producer attempts to flood us.
1634 sk->sk_backlog.len = 0;
1638 * sk_wait_data - wait for data to arrive at sk_receive_queue
1639 * @sk: sock to wait on
1640 * @timeo: for how long
1642 * Now socket state including sk->sk_err is changed only under lock,
1643 * hence we may omit checks after joining wait queue.
1644 * We check receive queue before schedule() only as optimization;
1645 * it is very likely that release_sock() added new data.
1647 int sk_wait_data(struct sock *sk, long *timeo)
1649 int rc;
1650 DEFINE_WAIT(wait);
1652 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1653 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1654 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1655 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1656 finish_wait(sk_sleep(sk), &wait);
1657 return rc;
1659 EXPORT_SYMBOL(sk_wait_data);
1662 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1663 * @sk: socket
1664 * @size: memory size to allocate
1665 * @kind: allocation type
1667 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
1668 * rmem allocation. This function assumes that protocols which have
1669 * memory_pressure use sk_wmem_queued as write buffer accounting.
1671 int __sk_mem_schedule(struct sock *sk, int size, int kind)
1673 struct proto *prot = sk->sk_prot;
1674 int amt = sk_mem_pages(size);
1675 long allocated;
1677 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
1678 allocated = atomic_long_add_return(amt, prot->memory_allocated);
1680 /* Under limit. */
1681 if (allocated <= prot->sysctl_mem[0]) {
1682 if (prot->memory_pressure && *prot->memory_pressure)
1683 *prot->memory_pressure = 0;
1684 return 1;
1687 /* Under pressure. */
1688 if (allocated > prot->sysctl_mem[1])
1689 if (prot->enter_memory_pressure)
1690 prot->enter_memory_pressure(sk);
1692 /* Over hard limit. */
1693 if (allocated > prot->sysctl_mem[2])
1694 goto suppress_allocation;
1696 /* guarantee minimum buffer size under pressure */
1697 if (kind == SK_MEM_RECV) {
1698 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
1699 return 1;
1700 } else { /* SK_MEM_SEND */
1701 if (sk->sk_type == SOCK_STREAM) {
1702 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
1703 return 1;
1704 } else if (atomic_read(&sk->sk_wmem_alloc) <
1705 prot->sysctl_wmem[0])
1706 return 1;
1709 if (prot->memory_pressure) {
1710 int alloc;
1712 if (!*prot->memory_pressure)
1713 return 1;
1714 alloc = percpu_counter_read_positive(prot->sockets_allocated);
1715 if (prot->sysctl_mem[2] > alloc *
1716 sk_mem_pages(sk->sk_wmem_queued +
1717 atomic_read(&sk->sk_rmem_alloc) +
1718 sk->sk_forward_alloc))
1719 return 1;
1722 suppress_allocation:
1724 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
1725 sk_stream_moderate_sndbuf(sk);
1727 /* Fail only if socket is _under_ its sndbuf.
1728 * In this case we cannot block, so that we have to fail.
1730 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
1731 return 1;
1734 trace_sock_exceed_buf_limit(sk, prot, allocated);
1736 /* Alas. Undo changes. */
1737 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
1738 atomic_long_sub(amt, prot->memory_allocated);
1739 return 0;
1741 EXPORT_SYMBOL(__sk_mem_schedule);
1744 * __sk_reclaim - reclaim memory_allocated
1745 * @sk: socket
1747 void __sk_mem_reclaim(struct sock *sk)
1749 struct proto *prot = sk->sk_prot;
1751 atomic_long_sub(sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT,
1752 prot->memory_allocated);
1753 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
1755 if (prot->memory_pressure && *prot->memory_pressure &&
1756 (atomic_long_read(prot->memory_allocated) < prot->sysctl_mem[0]))
1757 *prot->memory_pressure = 0;
1759 EXPORT_SYMBOL(__sk_mem_reclaim);
1763 * Set of default routines for initialising struct proto_ops when
1764 * the protocol does not support a particular function. In certain
1765 * cases where it makes no sense for a protocol to have a "do nothing"
1766 * function, some default processing is provided.
1769 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
1771 return -EOPNOTSUPP;
1773 EXPORT_SYMBOL(sock_no_bind);
1775 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
1776 int len, int flags)
1778 return -EOPNOTSUPP;
1780 EXPORT_SYMBOL(sock_no_connect);
1782 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
1784 return -EOPNOTSUPP;
1786 EXPORT_SYMBOL(sock_no_socketpair);
1788 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
1790 return -EOPNOTSUPP;
1792 EXPORT_SYMBOL(sock_no_accept);
1794 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
1795 int *len, int peer)
1797 return -EOPNOTSUPP;
1799 EXPORT_SYMBOL(sock_no_getname);
1801 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
1803 return 0;
1805 EXPORT_SYMBOL(sock_no_poll);
1807 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
1809 return -EOPNOTSUPP;
1811 EXPORT_SYMBOL(sock_no_ioctl);
1813 int sock_no_listen(struct socket *sock, int backlog)
1815 return -EOPNOTSUPP;
1817 EXPORT_SYMBOL(sock_no_listen);
1819 int sock_no_shutdown(struct socket *sock, int how)
1821 return -EOPNOTSUPP;
1823 EXPORT_SYMBOL(sock_no_shutdown);
1825 int sock_no_setsockopt(struct socket *sock, int level, int optname,
1826 char __user *optval, unsigned int optlen)
1828 return -EOPNOTSUPP;
1830 EXPORT_SYMBOL(sock_no_setsockopt);
1832 int sock_no_getsockopt(struct socket *sock, int level, int optname,
1833 char __user *optval, int __user *optlen)
1835 return -EOPNOTSUPP;
1837 EXPORT_SYMBOL(sock_no_getsockopt);
1839 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1840 size_t len)
1842 return -EOPNOTSUPP;
1844 EXPORT_SYMBOL(sock_no_sendmsg);
1846 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
1847 size_t len, int flags)
1849 return -EOPNOTSUPP;
1851 EXPORT_SYMBOL(sock_no_recvmsg);
1853 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
1855 /* Mirror missing mmap method error code */
1856 return -ENODEV;
1858 EXPORT_SYMBOL(sock_no_mmap);
1860 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
1862 ssize_t res;
1863 struct msghdr msg = {.msg_flags = flags};
1864 struct kvec iov;
1865 char *kaddr = kmap(page);
1866 iov.iov_base = kaddr + offset;
1867 iov.iov_len = size;
1868 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
1869 kunmap(page);
1870 return res;
1872 EXPORT_SYMBOL(sock_no_sendpage);
1875 * Default Socket Callbacks
1878 static void sock_def_wakeup(struct sock *sk)
1880 struct socket_wq *wq;
1882 rcu_read_lock();
1883 wq = rcu_dereference(sk->sk_wq);
1884 if (wq_has_sleeper(wq))
1885 wake_up_interruptible_all(&wq->wait);
1886 rcu_read_unlock();
1889 static void sock_def_error_report(struct sock *sk)
1891 struct socket_wq *wq;
1893 rcu_read_lock();
1894 wq = rcu_dereference(sk->sk_wq);
1895 if (wq_has_sleeper(wq))
1896 wake_up_interruptible_poll(&wq->wait, POLLERR);
1897 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
1898 rcu_read_unlock();
1901 static void sock_def_readable(struct sock *sk, int len)
1903 struct socket_wq *wq;
1905 rcu_read_lock();
1906 wq = rcu_dereference(sk->sk_wq);
1907 if (wq_has_sleeper(wq))
1908 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
1909 POLLRDNORM | POLLRDBAND);
1910 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
1911 rcu_read_unlock();
1914 static void sock_def_write_space(struct sock *sk)
1916 struct socket_wq *wq;
1918 rcu_read_lock();
1920 /* Do not wake up a writer until he can make "significant"
1921 * progress. --DaveM
1923 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
1924 wq = rcu_dereference(sk->sk_wq);
1925 if (wq_has_sleeper(wq))
1926 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
1927 POLLWRNORM | POLLWRBAND);
1929 /* Should agree with poll, otherwise some programs break */
1930 if (sock_writeable(sk))
1931 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
1934 rcu_read_unlock();
1937 static void sock_def_destruct(struct sock *sk)
1939 kfree(sk->sk_protinfo);
1942 void sk_send_sigurg(struct sock *sk)
1944 if (sk->sk_socket && sk->sk_socket->file)
1945 if (send_sigurg(&sk->sk_socket->file->f_owner))
1946 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
1948 EXPORT_SYMBOL(sk_send_sigurg);
1950 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
1951 unsigned long expires)
1953 if (!mod_timer(timer, expires))
1954 sock_hold(sk);
1956 EXPORT_SYMBOL(sk_reset_timer);
1958 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
1960 if (timer_pending(timer) && del_timer(timer))
1961 __sock_put(sk);
1963 EXPORT_SYMBOL(sk_stop_timer);
1965 void sock_init_data(struct socket *sock, struct sock *sk)
1967 skb_queue_head_init(&sk->sk_receive_queue);
1968 skb_queue_head_init(&sk->sk_write_queue);
1969 skb_queue_head_init(&sk->sk_error_queue);
1970 #ifdef CONFIG_NET_DMA
1971 skb_queue_head_init(&sk->sk_async_wait_queue);
1972 #endif
1974 sk->sk_send_head = NULL;
1976 init_timer(&sk->sk_timer);
1978 sk->sk_allocation = GFP_KERNEL;
1979 sk->sk_rcvbuf = sysctl_rmem_default;
1980 sk->sk_sndbuf = sysctl_wmem_default;
1981 sk->sk_state = TCP_CLOSE;
1982 sk_set_socket(sk, sock);
1984 sock_set_flag(sk, SOCK_ZAPPED);
1986 if (sock) {
1987 sk->sk_type = sock->type;
1988 sk->sk_wq = sock->wq;
1989 sock->sk = sk;
1990 } else
1991 sk->sk_wq = NULL;
1993 spin_lock_init(&sk->sk_dst_lock);
1994 rwlock_init(&sk->sk_callback_lock);
1995 lockdep_set_class_and_name(&sk->sk_callback_lock,
1996 af_callback_keys + sk->sk_family,
1997 af_family_clock_key_strings[sk->sk_family]);
1999 sk->sk_state_change = sock_def_wakeup;
2000 sk->sk_data_ready = sock_def_readable;
2001 sk->sk_write_space = sock_def_write_space;
2002 sk->sk_error_report = sock_def_error_report;
2003 sk->sk_destruct = sock_def_destruct;
2005 sk->sk_sndmsg_page = NULL;
2006 sk->sk_sndmsg_off = 0;
2008 sk->sk_peer_pid = NULL;
2009 sk->sk_peer_cred = NULL;
2010 sk->sk_write_pending = 0;
2011 sk->sk_rcvlowat = 1;
2012 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2013 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2015 sk->sk_stamp = ktime_set(-1L, 0);
2018 * Before updating sk_refcnt, we must commit prior changes to memory
2019 * (Documentation/RCU/rculist_nulls.txt for details)
2021 smp_wmb();
2022 atomic_set(&sk->sk_refcnt, 1);
2023 atomic_set(&sk->sk_drops, 0);
2025 EXPORT_SYMBOL(sock_init_data);
2027 void lock_sock_nested(struct sock *sk, int subclass)
2029 might_sleep();
2030 spin_lock_bh(&sk->sk_lock.slock);
2031 if (sk->sk_lock.owned)
2032 __lock_sock(sk);
2033 sk->sk_lock.owned = 1;
2034 spin_unlock(&sk->sk_lock.slock);
2036 * The sk_lock has mutex_lock() semantics here:
2038 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2039 local_bh_enable();
2041 EXPORT_SYMBOL(lock_sock_nested);
2043 void release_sock(struct sock *sk)
2046 * The sk_lock has mutex_unlock() semantics:
2048 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2050 spin_lock_bh(&sk->sk_lock.slock);
2051 if (sk->sk_backlog.tail)
2052 __release_sock(sk);
2053 sk->sk_lock.owned = 0;
2054 if (waitqueue_active(&sk->sk_lock.wq))
2055 wake_up(&sk->sk_lock.wq);
2056 spin_unlock_bh(&sk->sk_lock.slock);
2058 EXPORT_SYMBOL(release_sock);
2061 * lock_sock_fast - fast version of lock_sock
2062 * @sk: socket
2064 * This version should be used for very small section, where process wont block
2065 * return false if fast path is taken
2066 * sk_lock.slock locked, owned = 0, BH disabled
2067 * return true if slow path is taken
2068 * sk_lock.slock unlocked, owned = 1, BH enabled
2070 bool lock_sock_fast(struct sock *sk)
2072 might_sleep();
2073 spin_lock_bh(&sk->sk_lock.slock);
2075 if (!sk->sk_lock.owned)
2077 * Note : We must disable BH
2079 return false;
2081 __lock_sock(sk);
2082 sk->sk_lock.owned = 1;
2083 spin_unlock(&sk->sk_lock.slock);
2085 * The sk_lock has mutex_lock() semantics here:
2087 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2088 local_bh_enable();
2089 return true;
2091 EXPORT_SYMBOL(lock_sock_fast);
2093 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2095 struct timeval tv;
2096 if (!sock_flag(sk, SOCK_TIMESTAMP))
2097 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2098 tv = ktime_to_timeval(sk->sk_stamp);
2099 if (tv.tv_sec == -1)
2100 return -ENOENT;
2101 if (tv.tv_sec == 0) {
2102 sk->sk_stamp = ktime_get_real();
2103 tv = ktime_to_timeval(sk->sk_stamp);
2105 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2107 EXPORT_SYMBOL(sock_get_timestamp);
2109 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2111 struct timespec ts;
2112 if (!sock_flag(sk, SOCK_TIMESTAMP))
2113 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2114 ts = ktime_to_timespec(sk->sk_stamp);
2115 if (ts.tv_sec == -1)
2116 return -ENOENT;
2117 if (ts.tv_sec == 0) {
2118 sk->sk_stamp = ktime_get_real();
2119 ts = ktime_to_timespec(sk->sk_stamp);
2121 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2123 EXPORT_SYMBOL(sock_get_timestampns);
2125 void sock_enable_timestamp(struct sock *sk, int flag)
2127 if (!sock_flag(sk, flag)) {
2128 sock_set_flag(sk, flag);
2130 * we just set one of the two flags which require net
2131 * time stamping, but time stamping might have been on
2132 * already because of the other one
2134 if (!sock_flag(sk,
2135 flag == SOCK_TIMESTAMP ?
2136 SOCK_TIMESTAMPING_RX_SOFTWARE :
2137 SOCK_TIMESTAMP))
2138 net_enable_timestamp();
2143 * Get a socket option on an socket.
2145 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2146 * asynchronous errors should be reported by getsockopt. We assume
2147 * this means if you specify SO_ERROR (otherwise whats the point of it).
2149 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2150 char __user *optval, int __user *optlen)
2152 struct sock *sk = sock->sk;
2154 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2156 EXPORT_SYMBOL(sock_common_getsockopt);
2158 #ifdef CONFIG_COMPAT
2159 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2160 char __user *optval, int __user *optlen)
2162 struct sock *sk = sock->sk;
2164 if (sk->sk_prot->compat_getsockopt != NULL)
2165 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2166 optval, optlen);
2167 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2169 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2170 #endif
2172 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2173 struct msghdr *msg, size_t size, int flags)
2175 struct sock *sk = sock->sk;
2176 int addr_len = 0;
2177 int err;
2179 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2180 flags & ~MSG_DONTWAIT, &addr_len);
2181 if (err >= 0)
2182 msg->msg_namelen = addr_len;
2183 return err;
2185 EXPORT_SYMBOL(sock_common_recvmsg);
2188 * Set socket options on an inet socket.
2190 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2191 char __user *optval, unsigned int optlen)
2193 struct sock *sk = sock->sk;
2195 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2197 EXPORT_SYMBOL(sock_common_setsockopt);
2199 #ifdef CONFIG_COMPAT
2200 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2201 char __user *optval, unsigned int optlen)
2203 struct sock *sk = sock->sk;
2205 if (sk->sk_prot->compat_setsockopt != NULL)
2206 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2207 optval, optlen);
2208 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2210 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2211 #endif
2213 void sk_common_release(struct sock *sk)
2215 if (sk->sk_prot->destroy)
2216 sk->sk_prot->destroy(sk);
2219 * Observation: when sock_common_release is called, processes have
2220 * no access to socket. But net still has.
2221 * Step one, detach it from networking:
2223 * A. Remove from hash tables.
2226 sk->sk_prot->unhash(sk);
2229 * In this point socket cannot receive new packets, but it is possible
2230 * that some packets are in flight because some CPU runs receiver and
2231 * did hash table lookup before we unhashed socket. They will achieve
2232 * receive queue and will be purged by socket destructor.
2234 * Also we still have packets pending on receive queue and probably,
2235 * our own packets waiting in device queues. sock_destroy will drain
2236 * receive queue, but transmitted packets will delay socket destruction
2237 * until the last reference will be released.
2240 sock_orphan(sk);
2242 xfrm_sk_free_policy(sk);
2244 sk_refcnt_debug_release(sk);
2245 sock_put(sk);
2247 EXPORT_SYMBOL(sk_common_release);
2249 static DEFINE_RWLOCK(proto_list_lock);
2250 static LIST_HEAD(proto_list);
2252 #ifdef CONFIG_PROC_FS
2253 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
2254 struct prot_inuse {
2255 int val[PROTO_INUSE_NR];
2258 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2260 #ifdef CONFIG_NET_NS
2261 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2263 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2265 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2267 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2269 int cpu, idx = prot->inuse_idx;
2270 int res = 0;
2272 for_each_possible_cpu(cpu)
2273 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2275 return res >= 0 ? res : 0;
2277 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2279 static int __net_init sock_inuse_init_net(struct net *net)
2281 net->core.inuse = alloc_percpu(struct prot_inuse);
2282 return net->core.inuse ? 0 : -ENOMEM;
2285 static void __net_exit sock_inuse_exit_net(struct net *net)
2287 free_percpu(net->core.inuse);
2290 static struct pernet_operations net_inuse_ops = {
2291 .init = sock_inuse_init_net,
2292 .exit = sock_inuse_exit_net,
2295 static __init int net_inuse_init(void)
2297 if (register_pernet_subsys(&net_inuse_ops))
2298 panic("Cannot initialize net inuse counters");
2300 return 0;
2303 core_initcall(net_inuse_init);
2304 #else
2305 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2307 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2309 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2311 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2313 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2315 int cpu, idx = prot->inuse_idx;
2316 int res = 0;
2318 for_each_possible_cpu(cpu)
2319 res += per_cpu(prot_inuse, cpu).val[idx];
2321 return res >= 0 ? res : 0;
2323 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2324 #endif
2326 static void assign_proto_idx(struct proto *prot)
2328 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2330 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2331 printk(KERN_ERR "PROTO_INUSE_NR exhausted\n");
2332 return;
2335 set_bit(prot->inuse_idx, proto_inuse_idx);
2338 static void release_proto_idx(struct proto *prot)
2340 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2341 clear_bit(prot->inuse_idx, proto_inuse_idx);
2343 #else
2344 static inline void assign_proto_idx(struct proto *prot)
2348 static inline void release_proto_idx(struct proto *prot)
2351 #endif
2353 int proto_register(struct proto *prot, int alloc_slab)
2355 if (alloc_slab) {
2356 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2357 SLAB_HWCACHE_ALIGN | prot->slab_flags,
2358 NULL);
2360 if (prot->slab == NULL) {
2361 printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n",
2362 prot->name);
2363 goto out;
2366 if (prot->rsk_prot != NULL) {
2367 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2368 if (prot->rsk_prot->slab_name == NULL)
2369 goto out_free_sock_slab;
2371 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2372 prot->rsk_prot->obj_size, 0,
2373 SLAB_HWCACHE_ALIGN, NULL);
2375 if (prot->rsk_prot->slab == NULL) {
2376 printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n",
2377 prot->name);
2378 goto out_free_request_sock_slab_name;
2382 if (prot->twsk_prot != NULL) {
2383 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2385 if (prot->twsk_prot->twsk_slab_name == NULL)
2386 goto out_free_request_sock_slab;
2388 prot->twsk_prot->twsk_slab =
2389 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2390 prot->twsk_prot->twsk_obj_size,
2392 SLAB_HWCACHE_ALIGN |
2393 prot->slab_flags,
2394 NULL);
2395 if (prot->twsk_prot->twsk_slab == NULL)
2396 goto out_free_timewait_sock_slab_name;
2400 write_lock(&proto_list_lock);
2401 list_add(&prot->node, &proto_list);
2402 assign_proto_idx(prot);
2403 write_unlock(&proto_list_lock);
2404 return 0;
2406 out_free_timewait_sock_slab_name:
2407 kfree(prot->twsk_prot->twsk_slab_name);
2408 out_free_request_sock_slab:
2409 if (prot->rsk_prot && prot->rsk_prot->slab) {
2410 kmem_cache_destroy(prot->rsk_prot->slab);
2411 prot->rsk_prot->slab = NULL;
2413 out_free_request_sock_slab_name:
2414 if (prot->rsk_prot)
2415 kfree(prot->rsk_prot->slab_name);
2416 out_free_sock_slab:
2417 kmem_cache_destroy(prot->slab);
2418 prot->slab = NULL;
2419 out:
2420 return -ENOBUFS;
2422 EXPORT_SYMBOL(proto_register);
2424 void proto_unregister(struct proto *prot)
2426 write_lock(&proto_list_lock);
2427 release_proto_idx(prot);
2428 list_del(&prot->node);
2429 write_unlock(&proto_list_lock);
2431 if (prot->slab != NULL) {
2432 kmem_cache_destroy(prot->slab);
2433 prot->slab = NULL;
2436 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2437 kmem_cache_destroy(prot->rsk_prot->slab);
2438 kfree(prot->rsk_prot->slab_name);
2439 prot->rsk_prot->slab = NULL;
2442 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2443 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2444 kfree(prot->twsk_prot->twsk_slab_name);
2445 prot->twsk_prot->twsk_slab = NULL;
2448 EXPORT_SYMBOL(proto_unregister);
2450 #ifdef CONFIG_PROC_FS
2451 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2452 __acquires(proto_list_lock)
2454 read_lock(&proto_list_lock);
2455 return seq_list_start_head(&proto_list, *pos);
2458 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2460 return seq_list_next(v, &proto_list, pos);
2463 static void proto_seq_stop(struct seq_file *seq, void *v)
2464 __releases(proto_list_lock)
2466 read_unlock(&proto_list_lock);
2469 static char proto_method_implemented(const void *method)
2471 return method == NULL ? 'n' : 'y';
2474 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2476 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
2477 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2478 proto->name,
2479 proto->obj_size,
2480 sock_prot_inuse_get(seq_file_net(seq), proto),
2481 proto->memory_allocated != NULL ? atomic_long_read(proto->memory_allocated) : -1L,
2482 proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI",
2483 proto->max_header,
2484 proto->slab == NULL ? "no" : "yes",
2485 module_name(proto->owner),
2486 proto_method_implemented(proto->close),
2487 proto_method_implemented(proto->connect),
2488 proto_method_implemented(proto->disconnect),
2489 proto_method_implemented(proto->accept),
2490 proto_method_implemented(proto->ioctl),
2491 proto_method_implemented(proto->init),
2492 proto_method_implemented(proto->destroy),
2493 proto_method_implemented(proto->shutdown),
2494 proto_method_implemented(proto->setsockopt),
2495 proto_method_implemented(proto->getsockopt),
2496 proto_method_implemented(proto->sendmsg),
2497 proto_method_implemented(proto->recvmsg),
2498 proto_method_implemented(proto->sendpage),
2499 proto_method_implemented(proto->bind),
2500 proto_method_implemented(proto->backlog_rcv),
2501 proto_method_implemented(proto->hash),
2502 proto_method_implemented(proto->unhash),
2503 proto_method_implemented(proto->get_port),
2504 proto_method_implemented(proto->enter_memory_pressure));
2507 static int proto_seq_show(struct seq_file *seq, void *v)
2509 if (v == &proto_list)
2510 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2511 "protocol",
2512 "size",
2513 "sockets",
2514 "memory",
2515 "press",
2516 "maxhdr",
2517 "slab",
2518 "module",
2519 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2520 else
2521 proto_seq_printf(seq, list_entry(v, struct proto, node));
2522 return 0;
2525 static const struct seq_operations proto_seq_ops = {
2526 .start = proto_seq_start,
2527 .next = proto_seq_next,
2528 .stop = proto_seq_stop,
2529 .show = proto_seq_show,
2532 static int proto_seq_open(struct inode *inode, struct file *file)
2534 return seq_open_net(inode, file, &proto_seq_ops,
2535 sizeof(struct seq_net_private));
2538 static const struct file_operations proto_seq_fops = {
2539 .owner = THIS_MODULE,
2540 .open = proto_seq_open,
2541 .read = seq_read,
2542 .llseek = seq_lseek,
2543 .release = seq_release_net,
2546 static __net_init int proto_init_net(struct net *net)
2548 if (!proc_net_fops_create(net, "protocols", S_IRUGO, &proto_seq_fops))
2549 return -ENOMEM;
2551 return 0;
2554 static __net_exit void proto_exit_net(struct net *net)
2556 proc_net_remove(net, "protocols");
2560 static __net_initdata struct pernet_operations proto_net_ops = {
2561 .init = proto_init_net,
2562 .exit = proto_exit_net,
2565 static int __init proto_init(void)
2567 return register_pernet_subsys(&proto_net_ops);
2570 subsys_initcall(proto_init);
2572 #endif /* PROC_FS */