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Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
[mirror_ubuntu-artful-kernel.git] / net / core / sock.c
1 /*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * Generic socket support routines. Memory allocators, socket lock/release
7 * handler for protocols to use and generic option handler.
8 *
9 *
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Florian La Roche, <flla@stud.uni-sb.de>
13 * Alan Cox, <A.Cox@swansea.ac.uk>
14 *
15 * Fixes:
16 * Alan Cox : Numerous verify_area() problems
17 * Alan Cox : Connecting on a connecting socket
18 * now returns an error for tcp.
19 * Alan Cox : sock->protocol is set correctly.
20 * and is not sometimes left as 0.
21 * Alan Cox : connect handles icmp errors on a
22 * connect properly. Unfortunately there
23 * is a restart syscall nasty there. I
24 * can't match BSD without hacking the C
25 * library. Ideas urgently sought!
26 * Alan Cox : Disallow bind() to addresses that are
27 * not ours - especially broadcast ones!!
28 * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost)
29 * Alan Cox : sock_wfree/sock_rfree don't destroy sockets,
30 * instead they leave that for the DESTROY timer.
31 * Alan Cox : Clean up error flag in accept
32 * Alan Cox : TCP ack handling is buggy, the DESTROY timer
33 * was buggy. Put a remove_sock() in the handler
34 * for memory when we hit 0. Also altered the timer
35 * code. The ACK stuff can wait and needs major
36 * TCP layer surgery.
37 * Alan Cox : Fixed TCP ack bug, removed remove sock
38 * and fixed timer/inet_bh race.
39 * Alan Cox : Added zapped flag for TCP
40 * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code
41 * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42 * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources
43 * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing.
44 * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45 * Rick Sladkey : Relaxed UDP rules for matching packets.
46 * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support
47 * Pauline Middelink : identd support
48 * Alan Cox : Fixed connect() taking signals I think.
49 * Alan Cox : SO_LINGER supported
50 * Alan Cox : Error reporting fixes
51 * Anonymous : inet_create tidied up (sk->reuse setting)
52 * Alan Cox : inet sockets don't set sk->type!
53 * Alan Cox : Split socket option code
54 * Alan Cox : Callbacks
55 * Alan Cox : Nagle flag for Charles & Johannes stuff
56 * Alex : Removed restriction on inet fioctl
57 * Alan Cox : Splitting INET from NET core
58 * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt()
59 * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code
60 * Alan Cox : Split IP from generic code
61 * Alan Cox : New kfree_skbmem()
62 * Alan Cox : Make SO_DEBUG superuser only.
63 * Alan Cox : Allow anyone to clear SO_DEBUG
64 * (compatibility fix)
65 * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput.
66 * Alan Cox : Allocator for a socket is settable.
67 * Alan Cox : SO_ERROR includes soft errors.
68 * Alan Cox : Allow NULL arguments on some SO_ opts
69 * Alan Cox : Generic socket allocation to make hooks
70 * easier (suggested by Craig Metz).
71 * Michael Pall : SO_ERROR returns positive errno again
72 * Steve Whitehouse: Added default destructor to free
73 * protocol private data.
74 * Steve Whitehouse: Added various other default routines
75 * common to several socket families.
76 * Chris Evans : Call suser() check last on F_SETOWN
77 * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78 * Andi Kleen : Add sock_kmalloc()/sock_kfree_s()
79 * Andi Kleen : Fix write_space callback
80 * Chris Evans : Security fixes - signedness again
81 * Arnaldo C. Melo : cleanups, use skb_queue_purge
82 *
83 * To Fix:
84 *
85 *
86 * This program is free software; you can redistribute it and/or
87 * modify it under the terms of the GNU General Public License
88 * as published by the Free Software Foundation; either version
89 * 2 of the License, or (at your option) any later version.
90 */
91
92 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
93
94 #include <linux/capability.h>
95 #include <linux/errno.h>
96 #include <linux/errqueue.h>
97 #include <linux/types.h>
98 #include <linux/socket.h>
99 #include <linux/in.h>
100 #include <linux/kernel.h>
101 #include <linux/module.h>
102 #include <linux/proc_fs.h>
103 #include <linux/seq_file.h>
104 #include <linux/sched.h>
105 #include <linux/timer.h>
106 #include <linux/string.h>
107 #include <linux/sockios.h>
108 #include <linux/net.h>
109 #include <linux/mm.h>
110 #include <linux/slab.h>
111 #include <linux/interrupt.h>
112 #include <linux/poll.h>
113 #include <linux/tcp.h>
114 #include <linux/init.h>
115 #include <linux/highmem.h>
116 #include <linux/user_namespace.h>
117 #include <linux/static_key.h>
118 #include <linux/memcontrol.h>
119 #include <linux/prefetch.h>
120
121 #include <asm/uaccess.h>
122
123 #include <linux/netdevice.h>
124 #include <net/protocol.h>
125 #include <linux/skbuff.h>
126 #include <net/net_namespace.h>
127 #include <net/request_sock.h>
128 #include <net/sock.h>
129 #include <linux/net_tstamp.h>
130 #include <net/xfrm.h>
131 #include <linux/ipsec.h>
132 #include <net/cls_cgroup.h>
133 #include <net/netprio_cgroup.h>
134
135 #include <linux/filter.h>
136
137 #include <trace/events/sock.h>
138
139 #ifdef CONFIG_INET
140 #include <net/tcp.h>
141 #endif
142
143 #include <net/busy_poll.h>
144
145 static DEFINE_MUTEX(proto_list_mutex);
146 static LIST_HEAD(proto_list);
147
148 /**
149 * sk_ns_capable - General socket capability test
150 * @sk: Socket to use a capability on or through
151 * @user_ns: The user namespace of the capability to use
152 * @cap: The capability to use
153 *
154 * Test to see if the opener of the socket had when the socket was
155 * created and the current process has the capability @cap in the user
156 * namespace @user_ns.
157 */
158 bool sk_ns_capable(const struct sock *sk,
159 struct user_namespace *user_ns, int cap)
160 {
161 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
162 ns_capable(user_ns, cap);
163 }
164 EXPORT_SYMBOL(sk_ns_capable);
165
166 /**
167 * sk_capable - Socket global capability test
168 * @sk: Socket to use a capability on or through
169 * @cap: The global capbility to use
170 *
171 * Test to see if the opener of the socket had when the socket was
172 * created and the current process has the capability @cap in all user
173 * namespaces.
174 */
175 bool sk_capable(const struct sock *sk, int cap)
176 {
177 return sk_ns_capable(sk, &init_user_ns, cap);
178 }
179 EXPORT_SYMBOL(sk_capable);
180
181 /**
182 * sk_net_capable - Network namespace socket capability test
183 * @sk: Socket to use a capability on or through
184 * @cap: The capability to use
185 *
186 * Test to see if the opener of the socket had when the socke was created
187 * and the current process has the capability @cap over the network namespace
188 * the socket is a member of.
189 */
190 bool sk_net_capable(const struct sock *sk, int cap)
191 {
192 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
193 }
194 EXPORT_SYMBOL(sk_net_capable);
195
196
197 #ifdef CONFIG_MEMCG_KMEM
198 int mem_cgroup_sockets_init(struct mem_cgroup *memcg, struct cgroup_subsys *ss)
199 {
200 struct proto *proto;
201 int ret = 0;
202
203 mutex_lock(&proto_list_mutex);
204 list_for_each_entry(proto, &proto_list, node) {
205 if (proto->init_cgroup) {
206 ret = proto->init_cgroup(memcg, ss);
207 if (ret)
208 goto out;
209 }
210 }
211
212 mutex_unlock(&proto_list_mutex);
213 return ret;
214 out:
215 list_for_each_entry_continue_reverse(proto, &proto_list, node)
216 if (proto->destroy_cgroup)
217 proto->destroy_cgroup(memcg);
218 mutex_unlock(&proto_list_mutex);
219 return ret;
220 }
221
222 void mem_cgroup_sockets_destroy(struct mem_cgroup *memcg)
223 {
224 struct proto *proto;
225
226 mutex_lock(&proto_list_mutex);
227 list_for_each_entry_reverse(proto, &proto_list, node)
228 if (proto->destroy_cgroup)
229 proto->destroy_cgroup(memcg);
230 mutex_unlock(&proto_list_mutex);
231 }
232 #endif
233
234 /*
235 * Each address family might have different locking rules, so we have
236 * one slock key per address family:
237 */
238 static struct lock_class_key af_family_keys[AF_MAX];
239 static struct lock_class_key af_family_slock_keys[AF_MAX];
240
241 #if defined(CONFIG_MEMCG_KMEM)
242 struct static_key memcg_socket_limit_enabled;
243 EXPORT_SYMBOL(memcg_socket_limit_enabled);
244 #endif
245
246 /*
247 * Make lock validator output more readable. (we pre-construct these
248 * strings build-time, so that runtime initialization of socket
249 * locks is fast):
250 */
251 static const char *const af_family_key_strings[AF_MAX+1] = {
252 "sk_lock-AF_UNSPEC", "sk_lock-AF_UNIX" , "sk_lock-AF_INET" ,
253 "sk_lock-AF_AX25" , "sk_lock-AF_IPX" , "sk_lock-AF_APPLETALK",
254 "sk_lock-AF_NETROM", "sk_lock-AF_BRIDGE" , "sk_lock-AF_ATMPVC" ,
255 "sk_lock-AF_X25" , "sk_lock-AF_INET6" , "sk_lock-AF_ROSE" ,
256 "sk_lock-AF_DECnet", "sk_lock-AF_NETBEUI" , "sk_lock-AF_SECURITY" ,
257 "sk_lock-AF_KEY" , "sk_lock-AF_NETLINK" , "sk_lock-AF_PACKET" ,
258 "sk_lock-AF_ASH" , "sk_lock-AF_ECONET" , "sk_lock-AF_ATMSVC" ,
259 "sk_lock-AF_RDS" , "sk_lock-AF_SNA" , "sk_lock-AF_IRDA" ,
260 "sk_lock-AF_PPPOX" , "sk_lock-AF_WANPIPE" , "sk_lock-AF_LLC" ,
261 "sk_lock-27" , "sk_lock-28" , "sk_lock-AF_CAN" ,
262 "sk_lock-AF_TIPC" , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV" ,
263 "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN" , "sk_lock-AF_PHONET" ,
264 "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG" ,
265 "sk_lock-AF_NFC" , "sk_lock-AF_VSOCK" , "sk_lock-AF_MAX"
266 };
267 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
268 "slock-AF_UNSPEC", "slock-AF_UNIX" , "slock-AF_INET" ,
269 "slock-AF_AX25" , "slock-AF_IPX" , "slock-AF_APPLETALK",
270 "slock-AF_NETROM", "slock-AF_BRIDGE" , "slock-AF_ATMPVC" ,
271 "slock-AF_X25" , "slock-AF_INET6" , "slock-AF_ROSE" ,
272 "slock-AF_DECnet", "slock-AF_NETBEUI" , "slock-AF_SECURITY" ,
273 "slock-AF_KEY" , "slock-AF_NETLINK" , "slock-AF_PACKET" ,
274 "slock-AF_ASH" , "slock-AF_ECONET" , "slock-AF_ATMSVC" ,
275 "slock-AF_RDS" , "slock-AF_SNA" , "slock-AF_IRDA" ,
276 "slock-AF_PPPOX" , "slock-AF_WANPIPE" , "slock-AF_LLC" ,
277 "slock-27" , "slock-28" , "slock-AF_CAN" ,
278 "slock-AF_TIPC" , "slock-AF_BLUETOOTH", "slock-AF_IUCV" ,
279 "slock-AF_RXRPC" , "slock-AF_ISDN" , "slock-AF_PHONET" ,
280 "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG" ,
281 "slock-AF_NFC" , "slock-AF_VSOCK" ,"slock-AF_MAX"
282 };
283 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
284 "clock-AF_UNSPEC", "clock-AF_UNIX" , "clock-AF_INET" ,
285 "clock-AF_AX25" , "clock-AF_IPX" , "clock-AF_APPLETALK",
286 "clock-AF_NETROM", "clock-AF_BRIDGE" , "clock-AF_ATMPVC" ,
287 "clock-AF_X25" , "clock-AF_INET6" , "clock-AF_ROSE" ,
288 "clock-AF_DECnet", "clock-AF_NETBEUI" , "clock-AF_SECURITY" ,
289 "clock-AF_KEY" , "clock-AF_NETLINK" , "clock-AF_PACKET" ,
290 "clock-AF_ASH" , "clock-AF_ECONET" , "clock-AF_ATMSVC" ,
291 "clock-AF_RDS" , "clock-AF_SNA" , "clock-AF_IRDA" ,
292 "clock-AF_PPPOX" , "clock-AF_WANPIPE" , "clock-AF_LLC" ,
293 "clock-27" , "clock-28" , "clock-AF_CAN" ,
294 "clock-AF_TIPC" , "clock-AF_BLUETOOTH", "clock-AF_IUCV" ,
295 "clock-AF_RXRPC" , "clock-AF_ISDN" , "clock-AF_PHONET" ,
296 "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG" ,
297 "clock-AF_NFC" , "clock-AF_VSOCK" , "clock-AF_MAX"
298 };
299
300 /*
301 * sk_callback_lock locking rules are per-address-family,
302 * so split the lock classes by using a per-AF key:
303 */
304 static struct lock_class_key af_callback_keys[AF_MAX];
305
306 /* Take into consideration the size of the struct sk_buff overhead in the
307 * determination of these values, since that is non-constant across
308 * platforms. This makes socket queueing behavior and performance
309 * not depend upon such differences.
310 */
311 #define _SK_MEM_PACKETS 256
312 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
313 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
314 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
315
316 /* Run time adjustable parameters. */
317 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
318 EXPORT_SYMBOL(sysctl_wmem_max);
319 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
320 EXPORT_SYMBOL(sysctl_rmem_max);
321 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
322 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
323
324 /* Maximal space eaten by iovec or ancillary data plus some space */
325 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
326 EXPORT_SYMBOL(sysctl_optmem_max);
327
328 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
329 EXPORT_SYMBOL_GPL(memalloc_socks);
330
331 /**
332 * sk_set_memalloc - sets %SOCK_MEMALLOC
333 * @sk: socket to set it on
334 *
335 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
336 * It's the responsibility of the admin to adjust min_free_kbytes
337 * to meet the requirements
338 */
339 void sk_set_memalloc(struct sock *sk)
340 {
341 sock_set_flag(sk, SOCK_MEMALLOC);
342 sk->sk_allocation |= __GFP_MEMALLOC;
343 static_key_slow_inc(&memalloc_socks);
344 }
345 EXPORT_SYMBOL_GPL(sk_set_memalloc);
346
347 void sk_clear_memalloc(struct sock *sk)
348 {
349 sock_reset_flag(sk, SOCK_MEMALLOC);
350 sk->sk_allocation &= ~__GFP_MEMALLOC;
351 static_key_slow_dec(&memalloc_socks);
352
353 /*
354 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
355 * progress of swapping. However, if SOCK_MEMALLOC is cleared while
356 * it has rmem allocations there is a risk that the user of the
357 * socket cannot make forward progress due to exceeding the rmem
358 * limits. By rights, sk_clear_memalloc() should only be called
359 * on sockets being torn down but warn and reset the accounting if
360 * that assumption breaks.
361 */
362 if (WARN_ON(sk->sk_forward_alloc))
363 sk_mem_reclaim(sk);
364 }
365 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
366
367 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
368 {
369 int ret;
370 unsigned long pflags = current->flags;
371
372 /* these should have been dropped before queueing */
373 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
374
375 current->flags |= PF_MEMALLOC;
376 ret = sk->sk_backlog_rcv(sk, skb);
377 tsk_restore_flags(current, pflags, PF_MEMALLOC);
378
379 return ret;
380 }
381 EXPORT_SYMBOL(__sk_backlog_rcv);
382
383 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
384 {
385 struct timeval tv;
386
387 if (optlen < sizeof(tv))
388 return -EINVAL;
389 if (copy_from_user(&tv, optval, sizeof(tv)))
390 return -EFAULT;
391 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
392 return -EDOM;
393
394 if (tv.tv_sec < 0) {
395 static int warned __read_mostly;
396
397 *timeo_p = 0;
398 if (warned < 10 && net_ratelimit()) {
399 warned++;
400 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
401 __func__, current->comm, task_pid_nr(current));
402 }
403 return 0;
404 }
405 *timeo_p = MAX_SCHEDULE_TIMEOUT;
406 if (tv.tv_sec == 0 && tv.tv_usec == 0)
407 return 0;
408 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
409 *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ);
410 return 0;
411 }
412
413 static void sock_warn_obsolete_bsdism(const char *name)
414 {
415 static int warned;
416 static char warncomm[TASK_COMM_LEN];
417 if (strcmp(warncomm, current->comm) && warned < 5) {
418 strcpy(warncomm, current->comm);
419 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
420 warncomm, name);
421 warned++;
422 }
423 }
424
425 #define SK_FLAGS_TIMESTAMP ((1UL << SOCK_TIMESTAMP) | (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE))
426
427 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
428 {
429 if (sk->sk_flags & flags) {
430 sk->sk_flags &= ~flags;
431 if (!(sk->sk_flags & SK_FLAGS_TIMESTAMP))
432 net_disable_timestamp();
433 }
434 }
435
436
437 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
438 {
439 int err;
440 int skb_len;
441 unsigned long flags;
442 struct sk_buff_head *list = &sk->sk_receive_queue;
443
444 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
445 atomic_inc(&sk->sk_drops);
446 trace_sock_rcvqueue_full(sk, skb);
447 return -ENOMEM;
448 }
449
450 err = sk_filter(sk, skb);
451 if (err)
452 return err;
453
454 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
455 atomic_inc(&sk->sk_drops);
456 return -ENOBUFS;
457 }
458
459 skb->dev = NULL;
460 skb_set_owner_r(skb, sk);
461
462 /* Cache the SKB length before we tack it onto the receive
463 * queue. Once it is added it no longer belongs to us and
464 * may be freed by other threads of control pulling packets
465 * from the queue.
466 */
467 skb_len = skb->len;
468
469 /* we escape from rcu protected region, make sure we dont leak
470 * a norefcounted dst
471 */
472 skb_dst_force(skb);
473
474 spin_lock_irqsave(&list->lock, flags);
475 skb->dropcount = atomic_read(&sk->sk_drops);
476 __skb_queue_tail(list, skb);
477 spin_unlock_irqrestore(&list->lock, flags);
478
479 if (!sock_flag(sk, SOCK_DEAD))
480 sk->sk_data_ready(sk);
481 return 0;
482 }
483 EXPORT_SYMBOL(sock_queue_rcv_skb);
484
485 int sk_receive_skb(struct sock *sk, struct sk_buff *skb, const int nested)
486 {
487 int rc = NET_RX_SUCCESS;
488
489 if (sk_filter(sk, skb))
490 goto discard_and_relse;
491
492 skb->dev = NULL;
493
494 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
495 atomic_inc(&sk->sk_drops);
496 goto discard_and_relse;
497 }
498 if (nested)
499 bh_lock_sock_nested(sk);
500 else
501 bh_lock_sock(sk);
502 if (!sock_owned_by_user(sk)) {
503 /*
504 * trylock + unlock semantics:
505 */
506 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
507
508 rc = sk_backlog_rcv(sk, skb);
509
510 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
511 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
512 bh_unlock_sock(sk);
513 atomic_inc(&sk->sk_drops);
514 goto discard_and_relse;
515 }
516
517 bh_unlock_sock(sk);
518 out:
519 sock_put(sk);
520 return rc;
521 discard_and_relse:
522 kfree_skb(skb);
523 goto out;
524 }
525 EXPORT_SYMBOL(sk_receive_skb);
526
527 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
528 {
529 struct dst_entry *dst = __sk_dst_get(sk);
530
531 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
532 sk_tx_queue_clear(sk);
533 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
534 dst_release(dst);
535 return NULL;
536 }
537
538 return dst;
539 }
540 EXPORT_SYMBOL(__sk_dst_check);
541
542 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
543 {
544 struct dst_entry *dst = sk_dst_get(sk);
545
546 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
547 sk_dst_reset(sk);
548 dst_release(dst);
549 return NULL;
550 }
551
552 return dst;
553 }
554 EXPORT_SYMBOL(sk_dst_check);
555
556 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
557 int optlen)
558 {
559 int ret = -ENOPROTOOPT;
560 #ifdef CONFIG_NETDEVICES
561 struct net *net = sock_net(sk);
562 char devname[IFNAMSIZ];
563 int index;
564
565 /* Sorry... */
566 ret = -EPERM;
567 if (!ns_capable(net->user_ns, CAP_NET_RAW))
568 goto out;
569
570 ret = -EINVAL;
571 if (optlen < 0)
572 goto out;
573
574 /* Bind this socket to a particular device like "eth0",
575 * as specified in the passed interface name. If the
576 * name is "" or the option length is zero the socket
577 * is not bound.
578 */
579 if (optlen > IFNAMSIZ - 1)
580 optlen = IFNAMSIZ - 1;
581 memset(devname, 0, sizeof(devname));
582
583 ret = -EFAULT;
584 if (copy_from_user(devname, optval, optlen))
585 goto out;
586
587 index = 0;
588 if (devname[0] != '\0') {
589 struct net_device *dev;
590
591 rcu_read_lock();
592 dev = dev_get_by_name_rcu(net, devname);
593 if (dev)
594 index = dev->ifindex;
595 rcu_read_unlock();
596 ret = -ENODEV;
597 if (!dev)
598 goto out;
599 }
600
601 lock_sock(sk);
602 sk->sk_bound_dev_if = index;
603 sk_dst_reset(sk);
604 release_sock(sk);
605
606 ret = 0;
607
608 out:
609 #endif
610
611 return ret;
612 }
613
614 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
615 int __user *optlen, int len)
616 {
617 int ret = -ENOPROTOOPT;
618 #ifdef CONFIG_NETDEVICES
619 struct net *net = sock_net(sk);
620 char devname[IFNAMSIZ];
621
622 if (sk->sk_bound_dev_if == 0) {
623 len = 0;
624 goto zero;
625 }
626
627 ret = -EINVAL;
628 if (len < IFNAMSIZ)
629 goto out;
630
631 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
632 if (ret)
633 goto out;
634
635 len = strlen(devname) + 1;
636
637 ret = -EFAULT;
638 if (copy_to_user(optval, devname, len))
639 goto out;
640
641 zero:
642 ret = -EFAULT;
643 if (put_user(len, optlen))
644 goto out;
645
646 ret = 0;
647
648 out:
649 #endif
650
651 return ret;
652 }
653
654 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
655 {
656 if (valbool)
657 sock_set_flag(sk, bit);
658 else
659 sock_reset_flag(sk, bit);
660 }
661
662 /*
663 * This is meant for all protocols to use and covers goings on
664 * at the socket level. Everything here is generic.
665 */
666
667 int sock_setsockopt(struct socket *sock, int level, int optname,
668 char __user *optval, unsigned int optlen)
669 {
670 struct sock *sk = sock->sk;
671 int val;
672 int valbool;
673 struct linger ling;
674 int ret = 0;
675
676 /*
677 * Options without arguments
678 */
679
680 if (optname == SO_BINDTODEVICE)
681 return sock_setbindtodevice(sk, optval, optlen);
682
683 if (optlen < sizeof(int))
684 return -EINVAL;
685
686 if (get_user(val, (int __user *)optval))
687 return -EFAULT;
688
689 valbool = val ? 1 : 0;
690
691 lock_sock(sk);
692
693 switch (optname) {
694 case SO_DEBUG:
695 if (val && !capable(CAP_NET_ADMIN))
696 ret = -EACCES;
697 else
698 sock_valbool_flag(sk, SOCK_DBG, valbool);
699 break;
700 case SO_REUSEADDR:
701 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
702 break;
703 case SO_REUSEPORT:
704 sk->sk_reuseport = valbool;
705 break;
706 case SO_TYPE:
707 case SO_PROTOCOL:
708 case SO_DOMAIN:
709 case SO_ERROR:
710 ret = -ENOPROTOOPT;
711 break;
712 case SO_DONTROUTE:
713 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
714 break;
715 case SO_BROADCAST:
716 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
717 break;
718 case SO_SNDBUF:
719 /* Don't error on this BSD doesn't and if you think
720 * about it this is right. Otherwise apps have to
721 * play 'guess the biggest size' games. RCVBUF/SNDBUF
722 * are treated in BSD as hints
723 */
724 val = min_t(u32, val, sysctl_wmem_max);
725 set_sndbuf:
726 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
727 sk->sk_sndbuf = max_t(u32, val * 2, SOCK_MIN_SNDBUF);
728 /* Wake up sending tasks if we upped the value. */
729 sk->sk_write_space(sk);
730 break;
731
732 case SO_SNDBUFFORCE:
733 if (!capable(CAP_NET_ADMIN)) {
734 ret = -EPERM;
735 break;
736 }
737 goto set_sndbuf;
738
739 case SO_RCVBUF:
740 /* Don't error on this BSD doesn't and if you think
741 * about it this is right. Otherwise apps have to
742 * play 'guess the biggest size' games. RCVBUF/SNDBUF
743 * are treated in BSD as hints
744 */
745 val = min_t(u32, val, sysctl_rmem_max);
746 set_rcvbuf:
747 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
748 /*
749 * We double it on the way in to account for
750 * "struct sk_buff" etc. overhead. Applications
751 * assume that the SO_RCVBUF setting they make will
752 * allow that much actual data to be received on that
753 * socket.
754 *
755 * Applications are unaware that "struct sk_buff" and
756 * other overheads allocate from the receive buffer
757 * during socket buffer allocation.
758 *
759 * And after considering the possible alternatives,
760 * returning the value we actually used in getsockopt
761 * is the most desirable behavior.
762 */
763 sk->sk_rcvbuf = max_t(u32, val * 2, SOCK_MIN_RCVBUF);
764 break;
765
766 case SO_RCVBUFFORCE:
767 if (!capable(CAP_NET_ADMIN)) {
768 ret = -EPERM;
769 break;
770 }
771 goto set_rcvbuf;
772
773 case SO_KEEPALIVE:
774 #ifdef CONFIG_INET
775 if (sk->sk_protocol == IPPROTO_TCP &&
776 sk->sk_type == SOCK_STREAM)
777 tcp_set_keepalive(sk, valbool);
778 #endif
779 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
780 break;
781
782 case SO_OOBINLINE:
783 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
784 break;
785
786 case SO_NO_CHECK:
787 sk->sk_no_check_tx = valbool;
788 break;
789
790 case SO_PRIORITY:
791 if ((val >= 0 && val <= 6) ||
792 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
793 sk->sk_priority = val;
794 else
795 ret = -EPERM;
796 break;
797
798 case SO_LINGER:
799 if (optlen < sizeof(ling)) {
800 ret = -EINVAL; /* 1003.1g */
801 break;
802 }
803 if (copy_from_user(&ling, optval, sizeof(ling))) {
804 ret = -EFAULT;
805 break;
806 }
807 if (!ling.l_onoff)
808 sock_reset_flag(sk, SOCK_LINGER);
809 else {
810 #if (BITS_PER_LONG == 32)
811 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
812 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
813 else
814 #endif
815 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
816 sock_set_flag(sk, SOCK_LINGER);
817 }
818 break;
819
820 case SO_BSDCOMPAT:
821 sock_warn_obsolete_bsdism("setsockopt");
822 break;
823
824 case SO_PASSCRED:
825 if (valbool)
826 set_bit(SOCK_PASSCRED, &sock->flags);
827 else
828 clear_bit(SOCK_PASSCRED, &sock->flags);
829 break;
830
831 case SO_TIMESTAMP:
832 case SO_TIMESTAMPNS:
833 if (valbool) {
834 if (optname == SO_TIMESTAMP)
835 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
836 else
837 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
838 sock_set_flag(sk, SOCK_RCVTSTAMP);
839 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
840 } else {
841 sock_reset_flag(sk, SOCK_RCVTSTAMP);
842 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
843 }
844 break;
845
846 case SO_TIMESTAMPING:
847 if (val & ~SOF_TIMESTAMPING_MASK) {
848 ret = -EINVAL;
849 break;
850 }
851 if (val & SOF_TIMESTAMPING_OPT_ID &&
852 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
853 if (sk->sk_protocol == IPPROTO_TCP) {
854 if (sk->sk_state != TCP_ESTABLISHED) {
855 ret = -EINVAL;
856 break;
857 }
858 sk->sk_tskey = tcp_sk(sk)->snd_una;
859 } else {
860 sk->sk_tskey = 0;
861 }
862 }
863 sk->sk_tsflags = val;
864 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
865 sock_enable_timestamp(sk,
866 SOCK_TIMESTAMPING_RX_SOFTWARE);
867 else
868 sock_disable_timestamp(sk,
869 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
870 break;
871
872 case SO_RCVLOWAT:
873 if (val < 0)
874 val = INT_MAX;
875 sk->sk_rcvlowat = val ? : 1;
876 break;
877
878 case SO_RCVTIMEO:
879 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
880 break;
881
882 case SO_SNDTIMEO:
883 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
884 break;
885
886 case SO_ATTACH_FILTER:
887 ret = -EINVAL;
888 if (optlen == sizeof(struct sock_fprog)) {
889 struct sock_fprog fprog;
890
891 ret = -EFAULT;
892 if (copy_from_user(&fprog, optval, sizeof(fprog)))
893 break;
894
895 ret = sk_attach_filter(&fprog, sk);
896 }
897 break;
898
899 case SO_DETACH_FILTER:
900 ret = sk_detach_filter(sk);
901 break;
902
903 case SO_LOCK_FILTER:
904 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
905 ret = -EPERM;
906 else
907 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
908 break;
909
910 case SO_PASSSEC:
911 if (valbool)
912 set_bit(SOCK_PASSSEC, &sock->flags);
913 else
914 clear_bit(SOCK_PASSSEC, &sock->flags);
915 break;
916 case SO_MARK:
917 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
918 ret = -EPERM;
919 else
920 sk->sk_mark = val;
921 break;
922
923 /* We implement the SO_SNDLOWAT etc to
924 not be settable (1003.1g 5.3) */
925 case SO_RXQ_OVFL:
926 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
927 break;
928
929 case SO_WIFI_STATUS:
930 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
931 break;
932
933 case SO_PEEK_OFF:
934 if (sock->ops->set_peek_off)
935 ret = sock->ops->set_peek_off(sk, val);
936 else
937 ret = -EOPNOTSUPP;
938 break;
939
940 case SO_NOFCS:
941 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
942 break;
943
944 case SO_SELECT_ERR_QUEUE:
945 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
946 break;
947
948 #ifdef CONFIG_NET_RX_BUSY_POLL
949 case SO_BUSY_POLL:
950 /* allow unprivileged users to decrease the value */
951 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
952 ret = -EPERM;
953 else {
954 if (val < 0)
955 ret = -EINVAL;
956 else
957 sk->sk_ll_usec = val;
958 }
959 break;
960 #endif
961
962 case SO_MAX_PACING_RATE:
963 sk->sk_max_pacing_rate = val;
964 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
965 sk->sk_max_pacing_rate);
966 break;
967
968 default:
969 ret = -ENOPROTOOPT;
970 break;
971 }
972 release_sock(sk);
973 return ret;
974 }
975 EXPORT_SYMBOL(sock_setsockopt);
976
977
978 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
979 struct ucred *ucred)
980 {
981 ucred->pid = pid_vnr(pid);
982 ucred->uid = ucred->gid = -1;
983 if (cred) {
984 struct user_namespace *current_ns = current_user_ns();
985
986 ucred->uid = from_kuid_munged(current_ns, cred->euid);
987 ucred->gid = from_kgid_munged(current_ns, cred->egid);
988 }
989 }
990
991 int sock_getsockopt(struct socket *sock, int level, int optname,
992 char __user *optval, int __user *optlen)
993 {
994 struct sock *sk = sock->sk;
995
996 union {
997 int val;
998 struct linger ling;
999 struct timeval tm;
1000 } v;
1001
1002 int lv = sizeof(int);
1003 int len;
1004
1005 if (get_user(len, optlen))
1006 return -EFAULT;
1007 if (len < 0)
1008 return -EINVAL;
1009
1010 memset(&v, 0, sizeof(v));
1011
1012 switch (optname) {
1013 case SO_DEBUG:
1014 v.val = sock_flag(sk, SOCK_DBG);
1015 break;
1016
1017 case SO_DONTROUTE:
1018 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1019 break;
1020
1021 case SO_BROADCAST:
1022 v.val = sock_flag(sk, SOCK_BROADCAST);
1023 break;
1024
1025 case SO_SNDBUF:
1026 v.val = sk->sk_sndbuf;
1027 break;
1028
1029 case SO_RCVBUF:
1030 v.val = sk->sk_rcvbuf;
1031 break;
1032
1033 case SO_REUSEADDR:
1034 v.val = sk->sk_reuse;
1035 break;
1036
1037 case SO_REUSEPORT:
1038 v.val = sk->sk_reuseport;
1039 break;
1040
1041 case SO_KEEPALIVE:
1042 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1043 break;
1044
1045 case SO_TYPE:
1046 v.val = sk->sk_type;
1047 break;
1048
1049 case SO_PROTOCOL:
1050 v.val = sk->sk_protocol;
1051 break;
1052
1053 case SO_DOMAIN:
1054 v.val = sk->sk_family;
1055 break;
1056
1057 case SO_ERROR:
1058 v.val = -sock_error(sk);
1059 if (v.val == 0)
1060 v.val = xchg(&sk->sk_err_soft, 0);
1061 break;
1062
1063 case SO_OOBINLINE:
1064 v.val = sock_flag(sk, SOCK_URGINLINE);
1065 break;
1066
1067 case SO_NO_CHECK:
1068 v.val = sk->sk_no_check_tx;
1069 break;
1070
1071 case SO_PRIORITY:
1072 v.val = sk->sk_priority;
1073 break;
1074
1075 case SO_LINGER:
1076 lv = sizeof(v.ling);
1077 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1078 v.ling.l_linger = sk->sk_lingertime / HZ;
1079 break;
1080
1081 case SO_BSDCOMPAT:
1082 sock_warn_obsolete_bsdism("getsockopt");
1083 break;
1084
1085 case SO_TIMESTAMP:
1086 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1087 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1088 break;
1089
1090 case SO_TIMESTAMPNS:
1091 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1092 break;
1093
1094 case SO_TIMESTAMPING:
1095 v.val = sk->sk_tsflags;
1096 break;
1097
1098 case SO_RCVTIMEO:
1099 lv = sizeof(struct timeval);
1100 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1101 v.tm.tv_sec = 0;
1102 v.tm.tv_usec = 0;
1103 } else {
1104 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1105 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ;
1106 }
1107 break;
1108
1109 case SO_SNDTIMEO:
1110 lv = sizeof(struct timeval);
1111 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1112 v.tm.tv_sec = 0;
1113 v.tm.tv_usec = 0;
1114 } else {
1115 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1116 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ;
1117 }
1118 break;
1119
1120 case SO_RCVLOWAT:
1121 v.val = sk->sk_rcvlowat;
1122 break;
1123
1124 case SO_SNDLOWAT:
1125 v.val = 1;
1126 break;
1127
1128 case SO_PASSCRED:
1129 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1130 break;
1131
1132 case SO_PEERCRED:
1133 {
1134 struct ucred peercred;
1135 if (len > sizeof(peercred))
1136 len = sizeof(peercred);
1137 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1138 if (copy_to_user(optval, &peercred, len))
1139 return -EFAULT;
1140 goto lenout;
1141 }
1142
1143 case SO_PEERNAME:
1144 {
1145 char address[128];
1146
1147 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1148 return -ENOTCONN;
1149 if (lv < len)
1150 return -EINVAL;
1151 if (copy_to_user(optval, address, len))
1152 return -EFAULT;
1153 goto lenout;
1154 }
1155
1156 /* Dubious BSD thing... Probably nobody even uses it, but
1157 * the UNIX standard wants it for whatever reason... -DaveM
1158 */
1159 case SO_ACCEPTCONN:
1160 v.val = sk->sk_state == TCP_LISTEN;
1161 break;
1162
1163 case SO_PASSSEC:
1164 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1165 break;
1166
1167 case SO_PEERSEC:
1168 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1169
1170 case SO_MARK:
1171 v.val = sk->sk_mark;
1172 break;
1173
1174 case SO_RXQ_OVFL:
1175 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1176 break;
1177
1178 case SO_WIFI_STATUS:
1179 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1180 break;
1181
1182 case SO_PEEK_OFF:
1183 if (!sock->ops->set_peek_off)
1184 return -EOPNOTSUPP;
1185
1186 v.val = sk->sk_peek_off;
1187 break;
1188 case SO_NOFCS:
1189 v.val = sock_flag(sk, SOCK_NOFCS);
1190 break;
1191
1192 case SO_BINDTODEVICE:
1193 return sock_getbindtodevice(sk, optval, optlen, len);
1194
1195 case SO_GET_FILTER:
1196 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1197 if (len < 0)
1198 return len;
1199
1200 goto lenout;
1201
1202 case SO_LOCK_FILTER:
1203 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1204 break;
1205
1206 case SO_BPF_EXTENSIONS:
1207 v.val = bpf_tell_extensions();
1208 break;
1209
1210 case SO_SELECT_ERR_QUEUE:
1211 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1212 break;
1213
1214 #ifdef CONFIG_NET_RX_BUSY_POLL
1215 case SO_BUSY_POLL:
1216 v.val = sk->sk_ll_usec;
1217 break;
1218 #endif
1219
1220 case SO_MAX_PACING_RATE:
1221 v.val = sk->sk_max_pacing_rate;
1222 break;
1223
1224 default:
1225 return -ENOPROTOOPT;
1226 }
1227
1228 if (len > lv)
1229 len = lv;
1230 if (copy_to_user(optval, &v, len))
1231 return -EFAULT;
1232 lenout:
1233 if (put_user(len, optlen))
1234 return -EFAULT;
1235 return 0;
1236 }
1237
1238 /*
1239 * Initialize an sk_lock.
1240 *
1241 * (We also register the sk_lock with the lock validator.)
1242 */
1243 static inline void sock_lock_init(struct sock *sk)
1244 {
1245 sock_lock_init_class_and_name(sk,
1246 af_family_slock_key_strings[sk->sk_family],
1247 af_family_slock_keys + sk->sk_family,
1248 af_family_key_strings[sk->sk_family],
1249 af_family_keys + sk->sk_family);
1250 }
1251
1252 /*
1253 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1254 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1255 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1256 */
1257 static void sock_copy(struct sock *nsk, const struct sock *osk)
1258 {
1259 #ifdef CONFIG_SECURITY_NETWORK
1260 void *sptr = nsk->sk_security;
1261 #endif
1262 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1263
1264 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1265 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1266
1267 #ifdef CONFIG_SECURITY_NETWORK
1268 nsk->sk_security = sptr;
1269 security_sk_clone(osk, nsk);
1270 #endif
1271 }
1272
1273 void sk_prot_clear_portaddr_nulls(struct sock *sk, int size)
1274 {
1275 unsigned long nulls1, nulls2;
1276
1277 nulls1 = offsetof(struct sock, __sk_common.skc_node.next);
1278 nulls2 = offsetof(struct sock, __sk_common.skc_portaddr_node.next);
1279 if (nulls1 > nulls2)
1280 swap(nulls1, nulls2);
1281
1282 if (nulls1 != 0)
1283 memset((char *)sk, 0, nulls1);
1284 memset((char *)sk + nulls1 + sizeof(void *), 0,
1285 nulls2 - nulls1 - sizeof(void *));
1286 memset((char *)sk + nulls2 + sizeof(void *), 0,
1287 size - nulls2 - sizeof(void *));
1288 }
1289 EXPORT_SYMBOL(sk_prot_clear_portaddr_nulls);
1290
1291 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1292 int family)
1293 {
1294 struct sock *sk;
1295 struct kmem_cache *slab;
1296
1297 slab = prot->slab;
1298 if (slab != NULL) {
1299 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1300 if (!sk)
1301 return sk;
1302 if (priority & __GFP_ZERO) {
1303 if (prot->clear_sk)
1304 prot->clear_sk(sk, prot->obj_size);
1305 else
1306 sk_prot_clear_nulls(sk, prot->obj_size);
1307 }
1308 } else
1309 sk = kmalloc(prot->obj_size, priority);
1310
1311 if (sk != NULL) {
1312 kmemcheck_annotate_bitfield(sk, flags);
1313
1314 if (security_sk_alloc(sk, family, priority))
1315 goto out_free;
1316
1317 if (!try_module_get(prot->owner))
1318 goto out_free_sec;
1319 sk_tx_queue_clear(sk);
1320 }
1321
1322 return sk;
1323
1324 out_free_sec:
1325 security_sk_free(sk);
1326 out_free:
1327 if (slab != NULL)
1328 kmem_cache_free(slab, sk);
1329 else
1330 kfree(sk);
1331 return NULL;
1332 }
1333
1334 static void sk_prot_free(struct proto *prot, struct sock *sk)
1335 {
1336 struct kmem_cache *slab;
1337 struct module *owner;
1338
1339 owner = prot->owner;
1340 slab = prot->slab;
1341
1342 security_sk_free(sk);
1343 if (slab != NULL)
1344 kmem_cache_free(slab, sk);
1345 else
1346 kfree(sk);
1347 module_put(owner);
1348 }
1349
1350 #if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
1351 void sock_update_netprioidx(struct sock *sk)
1352 {
1353 if (in_interrupt())
1354 return;
1355
1356 sk->sk_cgrp_prioidx = task_netprioidx(current);
1357 }
1358 EXPORT_SYMBOL_GPL(sock_update_netprioidx);
1359 #endif
1360
1361 /**
1362 * sk_alloc - All socket objects are allocated here
1363 * @net: the applicable net namespace
1364 * @family: protocol family
1365 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1366 * @prot: struct proto associated with this new sock instance
1367 */
1368 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1369 struct proto *prot)
1370 {
1371 struct sock *sk;
1372
1373 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1374 if (sk) {
1375 sk->sk_family = family;
1376 /*
1377 * See comment in struct sock definition to understand
1378 * why we need sk_prot_creator -acme
1379 */
1380 sk->sk_prot = sk->sk_prot_creator = prot;
1381 sock_lock_init(sk);
1382 sock_net_set(sk, get_net(net));
1383 atomic_set(&sk->sk_wmem_alloc, 1);
1384
1385 sock_update_classid(sk);
1386 sock_update_netprioidx(sk);
1387 }
1388
1389 return sk;
1390 }
1391 EXPORT_SYMBOL(sk_alloc);
1392
1393 static void __sk_free(struct sock *sk)
1394 {
1395 struct sk_filter *filter;
1396
1397 if (sk->sk_destruct)
1398 sk->sk_destruct(sk);
1399
1400 filter = rcu_dereference_check(sk->sk_filter,
1401 atomic_read(&sk->sk_wmem_alloc) == 0);
1402 if (filter) {
1403 sk_filter_uncharge(sk, filter);
1404 RCU_INIT_POINTER(sk->sk_filter, NULL);
1405 }
1406
1407 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1408
1409 if (atomic_read(&sk->sk_omem_alloc))
1410 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1411 __func__, atomic_read(&sk->sk_omem_alloc));
1412
1413 if (sk->sk_peer_cred)
1414 put_cred(sk->sk_peer_cred);
1415 put_pid(sk->sk_peer_pid);
1416 put_net(sock_net(sk));
1417 sk_prot_free(sk->sk_prot_creator, sk);
1418 }
1419
1420 void sk_free(struct sock *sk)
1421 {
1422 /*
1423 * We subtract one from sk_wmem_alloc and can know if
1424 * some packets are still in some tx queue.
1425 * If not null, sock_wfree() will call __sk_free(sk) later
1426 */
1427 if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1428 __sk_free(sk);
1429 }
1430 EXPORT_SYMBOL(sk_free);
1431
1432 /*
1433 * Last sock_put should drop reference to sk->sk_net. It has already
1434 * been dropped in sk_change_net. Taking reference to stopping namespace
1435 * is not an option.
1436 * Take reference to a socket to remove it from hash _alive_ and after that
1437 * destroy it in the context of init_net.
1438 */
1439 void sk_release_kernel(struct sock *sk)
1440 {
1441 if (sk == NULL || sk->sk_socket == NULL)
1442 return;
1443
1444 sock_hold(sk);
1445 sock_release(sk->sk_socket);
1446 release_net(sock_net(sk));
1447 sock_net_set(sk, get_net(&init_net));
1448 sock_put(sk);
1449 }
1450 EXPORT_SYMBOL(sk_release_kernel);
1451
1452 static void sk_update_clone(const struct sock *sk, struct sock *newsk)
1453 {
1454 if (mem_cgroup_sockets_enabled && sk->sk_cgrp)
1455 sock_update_memcg(newsk);
1456 }
1457
1458 /**
1459 * sk_clone_lock - clone a socket, and lock its clone
1460 * @sk: the socket to clone
1461 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1462 *
1463 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1464 */
1465 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1466 {
1467 struct sock *newsk;
1468 bool is_charged = true;
1469
1470 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1471 if (newsk != NULL) {
1472 struct sk_filter *filter;
1473
1474 sock_copy(newsk, sk);
1475
1476 /* SANITY */
1477 get_net(sock_net(newsk));
1478 sk_node_init(&newsk->sk_node);
1479 sock_lock_init(newsk);
1480 bh_lock_sock(newsk);
1481 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1482 newsk->sk_backlog.len = 0;
1483
1484 atomic_set(&newsk->sk_rmem_alloc, 0);
1485 /*
1486 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1487 */
1488 atomic_set(&newsk->sk_wmem_alloc, 1);
1489 atomic_set(&newsk->sk_omem_alloc, 0);
1490 skb_queue_head_init(&newsk->sk_receive_queue);
1491 skb_queue_head_init(&newsk->sk_write_queue);
1492 #ifdef CONFIG_NET_DMA
1493 skb_queue_head_init(&newsk->sk_async_wait_queue);
1494 #endif
1495
1496 spin_lock_init(&newsk->sk_dst_lock);
1497 rwlock_init(&newsk->sk_callback_lock);
1498 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1499 af_callback_keys + newsk->sk_family,
1500 af_family_clock_key_strings[newsk->sk_family]);
1501
1502 newsk->sk_dst_cache = NULL;
1503 newsk->sk_wmem_queued = 0;
1504 newsk->sk_forward_alloc = 0;
1505 newsk->sk_send_head = NULL;
1506 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1507
1508 sock_reset_flag(newsk, SOCK_DONE);
1509 skb_queue_head_init(&newsk->sk_error_queue);
1510
1511 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1512 if (filter != NULL)
1513 /* though it's an empty new sock, the charging may fail
1514 * if sysctl_optmem_max was changed between creation of
1515 * original socket and cloning
1516 */
1517 is_charged = sk_filter_charge(newsk, filter);
1518
1519 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk))) {
1520 /* It is still raw copy of parent, so invalidate
1521 * destructor and make plain sk_free() */
1522 newsk->sk_destruct = NULL;
1523 bh_unlock_sock(newsk);
1524 sk_free(newsk);
1525 newsk = NULL;
1526 goto out;
1527 }
1528
1529 newsk->sk_err = 0;
1530 newsk->sk_priority = 0;
1531 /*
1532 * Before updating sk_refcnt, we must commit prior changes to memory
1533 * (Documentation/RCU/rculist_nulls.txt for details)
1534 */
1535 smp_wmb();
1536 atomic_set(&newsk->sk_refcnt, 2);
1537
1538 /*
1539 * Increment the counter in the same struct proto as the master
1540 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1541 * is the same as sk->sk_prot->socks, as this field was copied
1542 * with memcpy).
1543 *
1544 * This _changes_ the previous behaviour, where
1545 * tcp_create_openreq_child always was incrementing the
1546 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1547 * to be taken into account in all callers. -acme
1548 */
1549 sk_refcnt_debug_inc(newsk);
1550 sk_set_socket(newsk, NULL);
1551 newsk->sk_wq = NULL;
1552
1553 sk_update_clone(sk, newsk);
1554
1555 if (newsk->sk_prot->sockets_allocated)
1556 sk_sockets_allocated_inc(newsk);
1557
1558 if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1559 net_enable_timestamp();
1560 }
1561 out:
1562 return newsk;
1563 }
1564 EXPORT_SYMBOL_GPL(sk_clone_lock);
1565
1566 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1567 {
1568 __sk_dst_set(sk, dst);
1569 sk->sk_route_caps = dst->dev->features;
1570 if (sk->sk_route_caps & NETIF_F_GSO)
1571 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1572 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1573 if (sk_can_gso(sk)) {
1574 if (dst->header_len) {
1575 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1576 } else {
1577 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1578 sk->sk_gso_max_size = dst->dev->gso_max_size;
1579 sk->sk_gso_max_segs = dst->dev->gso_max_segs;
1580 }
1581 }
1582 }
1583 EXPORT_SYMBOL_GPL(sk_setup_caps);
1584
1585 /*
1586 * Simple resource managers for sockets.
1587 */
1588
1589
1590 /*
1591 * Write buffer destructor automatically called from kfree_skb.
1592 */
1593 void sock_wfree(struct sk_buff *skb)
1594 {
1595 struct sock *sk = skb->sk;
1596 unsigned int len = skb->truesize;
1597
1598 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1599 /*
1600 * Keep a reference on sk_wmem_alloc, this will be released
1601 * after sk_write_space() call
1602 */
1603 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1604 sk->sk_write_space(sk);
1605 len = 1;
1606 }
1607 /*
1608 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1609 * could not do because of in-flight packets
1610 */
1611 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1612 __sk_free(sk);
1613 }
1614 EXPORT_SYMBOL(sock_wfree);
1615
1616 void skb_orphan_partial(struct sk_buff *skb)
1617 {
1618 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
1619 * so we do not completely orphan skb, but transfert all
1620 * accounted bytes but one, to avoid unexpected reorders.
1621 */
1622 if (skb->destructor == sock_wfree
1623 #ifdef CONFIG_INET
1624 || skb->destructor == tcp_wfree
1625 #endif
1626 ) {
1627 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
1628 skb->truesize = 1;
1629 } else {
1630 skb_orphan(skb);
1631 }
1632 }
1633 EXPORT_SYMBOL(skb_orphan_partial);
1634
1635 /*
1636 * Read buffer destructor automatically called from kfree_skb.
1637 */
1638 void sock_rfree(struct sk_buff *skb)
1639 {
1640 struct sock *sk = skb->sk;
1641 unsigned int len = skb->truesize;
1642
1643 atomic_sub(len, &sk->sk_rmem_alloc);
1644 sk_mem_uncharge(sk, len);
1645 }
1646 EXPORT_SYMBOL(sock_rfree);
1647
1648 void sock_edemux(struct sk_buff *skb)
1649 {
1650 struct sock *sk = skb->sk;
1651
1652 #ifdef CONFIG_INET
1653 if (sk->sk_state == TCP_TIME_WAIT)
1654 inet_twsk_put(inet_twsk(sk));
1655 else
1656 #endif
1657 sock_put(sk);
1658 }
1659 EXPORT_SYMBOL(sock_edemux);
1660
1661 kuid_t sock_i_uid(struct sock *sk)
1662 {
1663 kuid_t uid;
1664
1665 read_lock_bh(&sk->sk_callback_lock);
1666 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1667 read_unlock_bh(&sk->sk_callback_lock);
1668 return uid;
1669 }
1670 EXPORT_SYMBOL(sock_i_uid);
1671
1672 unsigned long sock_i_ino(struct sock *sk)
1673 {
1674 unsigned long ino;
1675
1676 read_lock_bh(&sk->sk_callback_lock);
1677 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1678 read_unlock_bh(&sk->sk_callback_lock);
1679 return ino;
1680 }
1681 EXPORT_SYMBOL(sock_i_ino);
1682
1683 /*
1684 * Allocate a skb from the socket's send buffer.
1685 */
1686 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1687 gfp_t priority)
1688 {
1689 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1690 struct sk_buff *skb = alloc_skb(size, priority);
1691 if (skb) {
1692 skb_set_owner_w(skb, sk);
1693 return skb;
1694 }
1695 }
1696 return NULL;
1697 }
1698 EXPORT_SYMBOL(sock_wmalloc);
1699
1700 /*
1701 * Allocate a memory block from the socket's option memory buffer.
1702 */
1703 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1704 {
1705 if ((unsigned int)size <= sysctl_optmem_max &&
1706 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1707 void *mem;
1708 /* First do the add, to avoid the race if kmalloc
1709 * might sleep.
1710 */
1711 atomic_add(size, &sk->sk_omem_alloc);
1712 mem = kmalloc(size, priority);
1713 if (mem)
1714 return mem;
1715 atomic_sub(size, &sk->sk_omem_alloc);
1716 }
1717 return NULL;
1718 }
1719 EXPORT_SYMBOL(sock_kmalloc);
1720
1721 /*
1722 * Free an option memory block.
1723 */
1724 void sock_kfree_s(struct sock *sk, void *mem, int size)
1725 {
1726 kfree(mem);
1727 atomic_sub(size, &sk->sk_omem_alloc);
1728 }
1729 EXPORT_SYMBOL(sock_kfree_s);
1730
1731 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1732 I think, these locks should be removed for datagram sockets.
1733 */
1734 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1735 {
1736 DEFINE_WAIT(wait);
1737
1738 clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1739 for (;;) {
1740 if (!timeo)
1741 break;
1742 if (signal_pending(current))
1743 break;
1744 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1745 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1746 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1747 break;
1748 if (sk->sk_shutdown & SEND_SHUTDOWN)
1749 break;
1750 if (sk->sk_err)
1751 break;
1752 timeo = schedule_timeout(timeo);
1753 }
1754 finish_wait(sk_sleep(sk), &wait);
1755 return timeo;
1756 }
1757
1758
1759 /*
1760 * Generic send/receive buffer handlers
1761 */
1762
1763 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1764 unsigned long data_len, int noblock,
1765 int *errcode, int max_page_order)
1766 {
1767 struct sk_buff *skb = NULL;
1768 unsigned long chunk;
1769 gfp_t gfp_mask;
1770 long timeo;
1771 int err;
1772 int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
1773 struct page *page;
1774 int i;
1775
1776 err = -EMSGSIZE;
1777 if (npages > MAX_SKB_FRAGS)
1778 goto failure;
1779
1780 timeo = sock_sndtimeo(sk, noblock);
1781 while (!skb) {
1782 err = sock_error(sk);
1783 if (err != 0)
1784 goto failure;
1785
1786 err = -EPIPE;
1787 if (sk->sk_shutdown & SEND_SHUTDOWN)
1788 goto failure;
1789
1790 if (atomic_read(&sk->sk_wmem_alloc) >= sk->sk_sndbuf) {
1791 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1792 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1793 err = -EAGAIN;
1794 if (!timeo)
1795 goto failure;
1796 if (signal_pending(current))
1797 goto interrupted;
1798 timeo = sock_wait_for_wmem(sk, timeo);
1799 continue;
1800 }
1801
1802 err = -ENOBUFS;
1803 gfp_mask = sk->sk_allocation;
1804 if (gfp_mask & __GFP_WAIT)
1805 gfp_mask |= __GFP_REPEAT;
1806
1807 skb = alloc_skb(header_len, gfp_mask);
1808 if (!skb)
1809 goto failure;
1810
1811 skb->truesize += data_len;
1812
1813 for (i = 0; npages > 0; i++) {
1814 int order = max_page_order;
1815
1816 while (order) {
1817 if (npages >= 1 << order) {
1818 page = alloc_pages(sk->sk_allocation |
1819 __GFP_COMP |
1820 __GFP_NOWARN |
1821 __GFP_NORETRY,
1822 order);
1823 if (page)
1824 goto fill_page;
1825 }
1826 order--;
1827 }
1828 page = alloc_page(sk->sk_allocation);
1829 if (!page)
1830 goto failure;
1831 fill_page:
1832 chunk = min_t(unsigned long, data_len,
1833 PAGE_SIZE << order);
1834 skb_fill_page_desc(skb, i, page, 0, chunk);
1835 data_len -= chunk;
1836 npages -= 1 << order;
1837 }
1838 }
1839
1840 skb_set_owner_w(skb, sk);
1841 return skb;
1842
1843 interrupted:
1844 err = sock_intr_errno(timeo);
1845 failure:
1846 kfree_skb(skb);
1847 *errcode = err;
1848 return NULL;
1849 }
1850 EXPORT_SYMBOL(sock_alloc_send_pskb);
1851
1852 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1853 int noblock, int *errcode)
1854 {
1855 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1856 }
1857 EXPORT_SYMBOL(sock_alloc_send_skb);
1858
1859 /* On 32bit arches, an skb frag is limited to 2^15 */
1860 #define SKB_FRAG_PAGE_ORDER get_order(32768)
1861
1862 /**
1863 * skb_page_frag_refill - check that a page_frag contains enough room
1864 * @sz: minimum size of the fragment we want to get
1865 * @pfrag: pointer to page_frag
1866 * @prio: priority for memory allocation
1867 *
1868 * Note: While this allocator tries to use high order pages, there is
1869 * no guarantee that allocations succeed. Therefore, @sz MUST be
1870 * less or equal than PAGE_SIZE.
1871 */
1872 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t prio)
1873 {
1874 int order;
1875
1876 if (pfrag->page) {
1877 if (atomic_read(&pfrag->page->_count) == 1) {
1878 pfrag->offset = 0;
1879 return true;
1880 }
1881 if (pfrag->offset + sz <= pfrag->size)
1882 return true;
1883 put_page(pfrag->page);
1884 }
1885
1886 order = SKB_FRAG_PAGE_ORDER;
1887 do {
1888 gfp_t gfp = prio;
1889
1890 if (order)
1891 gfp |= __GFP_COMP | __GFP_NOWARN | __GFP_NORETRY;
1892 pfrag->page = alloc_pages(gfp, order);
1893 if (likely(pfrag->page)) {
1894 pfrag->offset = 0;
1895 pfrag->size = PAGE_SIZE << order;
1896 return true;
1897 }
1898 } while (--order >= 0);
1899
1900 return false;
1901 }
1902 EXPORT_SYMBOL(skb_page_frag_refill);
1903
1904 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
1905 {
1906 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
1907 return true;
1908
1909 sk_enter_memory_pressure(sk);
1910 sk_stream_moderate_sndbuf(sk);
1911 return false;
1912 }
1913 EXPORT_SYMBOL(sk_page_frag_refill);
1914
1915 static void __lock_sock(struct sock *sk)
1916 __releases(&sk->sk_lock.slock)
1917 __acquires(&sk->sk_lock.slock)
1918 {
1919 DEFINE_WAIT(wait);
1920
1921 for (;;) {
1922 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
1923 TASK_UNINTERRUPTIBLE);
1924 spin_unlock_bh(&sk->sk_lock.slock);
1925 schedule();
1926 spin_lock_bh(&sk->sk_lock.slock);
1927 if (!sock_owned_by_user(sk))
1928 break;
1929 }
1930 finish_wait(&sk->sk_lock.wq, &wait);
1931 }
1932
1933 static void __release_sock(struct sock *sk)
1934 __releases(&sk->sk_lock.slock)
1935 __acquires(&sk->sk_lock.slock)
1936 {
1937 struct sk_buff *skb = sk->sk_backlog.head;
1938
1939 do {
1940 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
1941 bh_unlock_sock(sk);
1942
1943 do {
1944 struct sk_buff *next = skb->next;
1945
1946 prefetch(next);
1947 WARN_ON_ONCE(skb_dst_is_noref(skb));
1948 skb->next = NULL;
1949 sk_backlog_rcv(sk, skb);
1950
1951 /*
1952 * We are in process context here with softirqs
1953 * disabled, use cond_resched_softirq() to preempt.
1954 * This is safe to do because we've taken the backlog
1955 * queue private:
1956 */
1957 cond_resched_softirq();
1958
1959 skb = next;
1960 } while (skb != NULL);
1961
1962 bh_lock_sock(sk);
1963 } while ((skb = sk->sk_backlog.head) != NULL);
1964
1965 /*
1966 * Doing the zeroing here guarantee we can not loop forever
1967 * while a wild producer attempts to flood us.
1968 */
1969 sk->sk_backlog.len = 0;
1970 }
1971
1972 /**
1973 * sk_wait_data - wait for data to arrive at sk_receive_queue
1974 * @sk: sock to wait on
1975 * @timeo: for how long
1976 *
1977 * Now socket state including sk->sk_err is changed only under lock,
1978 * hence we may omit checks after joining wait queue.
1979 * We check receive queue before schedule() only as optimization;
1980 * it is very likely that release_sock() added new data.
1981 */
1982 int sk_wait_data(struct sock *sk, long *timeo)
1983 {
1984 int rc;
1985 DEFINE_WAIT(wait);
1986
1987 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1988 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1989 rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue));
1990 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
1991 finish_wait(sk_sleep(sk), &wait);
1992 return rc;
1993 }
1994 EXPORT_SYMBOL(sk_wait_data);
1995
1996 /**
1997 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
1998 * @sk: socket
1999 * @size: memory size to allocate
2000 * @kind: allocation type
2001 *
2002 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2003 * rmem allocation. This function assumes that protocols which have
2004 * memory_pressure use sk_wmem_queued as write buffer accounting.
2005 */
2006 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2007 {
2008 struct proto *prot = sk->sk_prot;
2009 int amt = sk_mem_pages(size);
2010 long allocated;
2011 int parent_status = UNDER_LIMIT;
2012
2013 sk->sk_forward_alloc += amt * SK_MEM_QUANTUM;
2014
2015 allocated = sk_memory_allocated_add(sk, amt, &parent_status);
2016
2017 /* Under limit. */
2018 if (parent_status == UNDER_LIMIT &&
2019 allocated <= sk_prot_mem_limits(sk, 0)) {
2020 sk_leave_memory_pressure(sk);
2021 return 1;
2022 }
2023
2024 /* Under pressure. (we or our parents) */
2025 if ((parent_status > SOFT_LIMIT) ||
2026 allocated > sk_prot_mem_limits(sk, 1))
2027 sk_enter_memory_pressure(sk);
2028
2029 /* Over hard limit (we or our parents) */
2030 if ((parent_status == OVER_LIMIT) ||
2031 (allocated > sk_prot_mem_limits(sk, 2)))
2032 goto suppress_allocation;
2033
2034 /* guarantee minimum buffer size under pressure */
2035 if (kind == SK_MEM_RECV) {
2036 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2037 return 1;
2038
2039 } else { /* SK_MEM_SEND */
2040 if (sk->sk_type == SOCK_STREAM) {
2041 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2042 return 1;
2043 } else if (atomic_read(&sk->sk_wmem_alloc) <
2044 prot->sysctl_wmem[0])
2045 return 1;
2046 }
2047
2048 if (sk_has_memory_pressure(sk)) {
2049 int alloc;
2050
2051 if (!sk_under_memory_pressure(sk))
2052 return 1;
2053 alloc = sk_sockets_allocated_read_positive(sk);
2054 if (sk_prot_mem_limits(sk, 2) > alloc *
2055 sk_mem_pages(sk->sk_wmem_queued +
2056 atomic_read(&sk->sk_rmem_alloc) +
2057 sk->sk_forward_alloc))
2058 return 1;
2059 }
2060
2061 suppress_allocation:
2062
2063 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2064 sk_stream_moderate_sndbuf(sk);
2065
2066 /* Fail only if socket is _under_ its sndbuf.
2067 * In this case we cannot block, so that we have to fail.
2068 */
2069 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2070 return 1;
2071 }
2072
2073 trace_sock_exceed_buf_limit(sk, prot, allocated);
2074
2075 /* Alas. Undo changes. */
2076 sk->sk_forward_alloc -= amt * SK_MEM_QUANTUM;
2077
2078 sk_memory_allocated_sub(sk, amt);
2079
2080 return 0;
2081 }
2082 EXPORT_SYMBOL(__sk_mem_schedule);
2083
2084 /**
2085 * __sk_reclaim - reclaim memory_allocated
2086 * @sk: socket
2087 */
2088 void __sk_mem_reclaim(struct sock *sk)
2089 {
2090 sk_memory_allocated_sub(sk,
2091 sk->sk_forward_alloc >> SK_MEM_QUANTUM_SHIFT);
2092 sk->sk_forward_alloc &= SK_MEM_QUANTUM - 1;
2093
2094 if (sk_under_memory_pressure(sk) &&
2095 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2096 sk_leave_memory_pressure(sk);
2097 }
2098 EXPORT_SYMBOL(__sk_mem_reclaim);
2099
2100
2101 /*
2102 * Set of default routines for initialising struct proto_ops when
2103 * the protocol does not support a particular function. In certain
2104 * cases where it makes no sense for a protocol to have a "do nothing"
2105 * function, some default processing is provided.
2106 */
2107
2108 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2109 {
2110 return -EOPNOTSUPP;
2111 }
2112 EXPORT_SYMBOL(sock_no_bind);
2113
2114 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2115 int len, int flags)
2116 {
2117 return -EOPNOTSUPP;
2118 }
2119 EXPORT_SYMBOL(sock_no_connect);
2120
2121 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2122 {
2123 return -EOPNOTSUPP;
2124 }
2125 EXPORT_SYMBOL(sock_no_socketpair);
2126
2127 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags)
2128 {
2129 return -EOPNOTSUPP;
2130 }
2131 EXPORT_SYMBOL(sock_no_accept);
2132
2133 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2134 int *len, int peer)
2135 {
2136 return -EOPNOTSUPP;
2137 }
2138 EXPORT_SYMBOL(sock_no_getname);
2139
2140 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2141 {
2142 return 0;
2143 }
2144 EXPORT_SYMBOL(sock_no_poll);
2145
2146 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2147 {
2148 return -EOPNOTSUPP;
2149 }
2150 EXPORT_SYMBOL(sock_no_ioctl);
2151
2152 int sock_no_listen(struct socket *sock, int backlog)
2153 {
2154 return -EOPNOTSUPP;
2155 }
2156 EXPORT_SYMBOL(sock_no_listen);
2157
2158 int sock_no_shutdown(struct socket *sock, int how)
2159 {
2160 return -EOPNOTSUPP;
2161 }
2162 EXPORT_SYMBOL(sock_no_shutdown);
2163
2164 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2165 char __user *optval, unsigned int optlen)
2166 {
2167 return -EOPNOTSUPP;
2168 }
2169 EXPORT_SYMBOL(sock_no_setsockopt);
2170
2171 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2172 char __user *optval, int __user *optlen)
2173 {
2174 return -EOPNOTSUPP;
2175 }
2176 EXPORT_SYMBOL(sock_no_getsockopt);
2177
2178 int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2179 size_t len)
2180 {
2181 return -EOPNOTSUPP;
2182 }
2183 EXPORT_SYMBOL(sock_no_sendmsg);
2184
2185 int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m,
2186 size_t len, int flags)
2187 {
2188 return -EOPNOTSUPP;
2189 }
2190 EXPORT_SYMBOL(sock_no_recvmsg);
2191
2192 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2193 {
2194 /* Mirror missing mmap method error code */
2195 return -ENODEV;
2196 }
2197 EXPORT_SYMBOL(sock_no_mmap);
2198
2199 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2200 {
2201 ssize_t res;
2202 struct msghdr msg = {.msg_flags = flags};
2203 struct kvec iov;
2204 char *kaddr = kmap(page);
2205 iov.iov_base = kaddr + offset;
2206 iov.iov_len = size;
2207 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2208 kunmap(page);
2209 return res;
2210 }
2211 EXPORT_SYMBOL(sock_no_sendpage);
2212
2213 /*
2214 * Default Socket Callbacks
2215 */
2216
2217 static void sock_def_wakeup(struct sock *sk)
2218 {
2219 struct socket_wq *wq;
2220
2221 rcu_read_lock();
2222 wq = rcu_dereference(sk->sk_wq);
2223 if (wq_has_sleeper(wq))
2224 wake_up_interruptible_all(&wq->wait);
2225 rcu_read_unlock();
2226 }
2227
2228 static void sock_def_error_report(struct sock *sk)
2229 {
2230 struct socket_wq *wq;
2231
2232 rcu_read_lock();
2233 wq = rcu_dereference(sk->sk_wq);
2234 if (wq_has_sleeper(wq))
2235 wake_up_interruptible_poll(&wq->wait, POLLERR);
2236 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2237 rcu_read_unlock();
2238 }
2239
2240 static void sock_def_readable(struct sock *sk)
2241 {
2242 struct socket_wq *wq;
2243
2244 rcu_read_lock();
2245 wq = rcu_dereference(sk->sk_wq);
2246 if (wq_has_sleeper(wq))
2247 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2248 POLLRDNORM | POLLRDBAND);
2249 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2250 rcu_read_unlock();
2251 }
2252
2253 static void sock_def_write_space(struct sock *sk)
2254 {
2255 struct socket_wq *wq;
2256
2257 rcu_read_lock();
2258
2259 /* Do not wake up a writer until he can make "significant"
2260 * progress. --DaveM
2261 */
2262 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2263 wq = rcu_dereference(sk->sk_wq);
2264 if (wq_has_sleeper(wq))
2265 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2266 POLLWRNORM | POLLWRBAND);
2267
2268 /* Should agree with poll, otherwise some programs break */
2269 if (sock_writeable(sk))
2270 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2271 }
2272
2273 rcu_read_unlock();
2274 }
2275
2276 static void sock_def_destruct(struct sock *sk)
2277 {
2278 kfree(sk->sk_protinfo);
2279 }
2280
2281 void sk_send_sigurg(struct sock *sk)
2282 {
2283 if (sk->sk_socket && sk->sk_socket->file)
2284 if (send_sigurg(&sk->sk_socket->file->f_owner))
2285 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2286 }
2287 EXPORT_SYMBOL(sk_send_sigurg);
2288
2289 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2290 unsigned long expires)
2291 {
2292 if (!mod_timer(timer, expires))
2293 sock_hold(sk);
2294 }
2295 EXPORT_SYMBOL(sk_reset_timer);
2296
2297 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2298 {
2299 if (del_timer(timer))
2300 __sock_put(sk);
2301 }
2302 EXPORT_SYMBOL(sk_stop_timer);
2303
2304 void sock_init_data(struct socket *sock, struct sock *sk)
2305 {
2306 skb_queue_head_init(&sk->sk_receive_queue);
2307 skb_queue_head_init(&sk->sk_write_queue);
2308 skb_queue_head_init(&sk->sk_error_queue);
2309 #ifdef CONFIG_NET_DMA
2310 skb_queue_head_init(&sk->sk_async_wait_queue);
2311 #endif
2312
2313 sk->sk_send_head = NULL;
2314
2315 init_timer(&sk->sk_timer);
2316
2317 sk->sk_allocation = GFP_KERNEL;
2318 sk->sk_rcvbuf = sysctl_rmem_default;
2319 sk->sk_sndbuf = sysctl_wmem_default;
2320 sk->sk_state = TCP_CLOSE;
2321 sk_set_socket(sk, sock);
2322
2323 sock_set_flag(sk, SOCK_ZAPPED);
2324
2325 if (sock) {
2326 sk->sk_type = sock->type;
2327 sk->sk_wq = sock->wq;
2328 sock->sk = sk;
2329 } else
2330 sk->sk_wq = NULL;
2331
2332 spin_lock_init(&sk->sk_dst_lock);
2333 rwlock_init(&sk->sk_callback_lock);
2334 lockdep_set_class_and_name(&sk->sk_callback_lock,
2335 af_callback_keys + sk->sk_family,
2336 af_family_clock_key_strings[sk->sk_family]);
2337
2338 sk->sk_state_change = sock_def_wakeup;
2339 sk->sk_data_ready = sock_def_readable;
2340 sk->sk_write_space = sock_def_write_space;
2341 sk->sk_error_report = sock_def_error_report;
2342 sk->sk_destruct = sock_def_destruct;
2343
2344 sk->sk_frag.page = NULL;
2345 sk->sk_frag.offset = 0;
2346 sk->sk_peek_off = -1;
2347
2348 sk->sk_peer_pid = NULL;
2349 sk->sk_peer_cred = NULL;
2350 sk->sk_write_pending = 0;
2351 sk->sk_rcvlowat = 1;
2352 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2353 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2354
2355 sk->sk_stamp = ktime_set(-1L, 0);
2356
2357 #ifdef CONFIG_NET_RX_BUSY_POLL
2358 sk->sk_napi_id = 0;
2359 sk->sk_ll_usec = sysctl_net_busy_read;
2360 #endif
2361
2362 sk->sk_max_pacing_rate = ~0U;
2363 sk->sk_pacing_rate = ~0U;
2364 /*
2365 * Before updating sk_refcnt, we must commit prior changes to memory
2366 * (Documentation/RCU/rculist_nulls.txt for details)
2367 */
2368 smp_wmb();
2369 atomic_set(&sk->sk_refcnt, 1);
2370 atomic_set(&sk->sk_drops, 0);
2371 }
2372 EXPORT_SYMBOL(sock_init_data);
2373
2374 void lock_sock_nested(struct sock *sk, int subclass)
2375 {
2376 might_sleep();
2377 spin_lock_bh(&sk->sk_lock.slock);
2378 if (sk->sk_lock.owned)
2379 __lock_sock(sk);
2380 sk->sk_lock.owned = 1;
2381 spin_unlock(&sk->sk_lock.slock);
2382 /*
2383 * The sk_lock has mutex_lock() semantics here:
2384 */
2385 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2386 local_bh_enable();
2387 }
2388 EXPORT_SYMBOL(lock_sock_nested);
2389
2390 void release_sock(struct sock *sk)
2391 {
2392 /*
2393 * The sk_lock has mutex_unlock() semantics:
2394 */
2395 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
2396
2397 spin_lock_bh(&sk->sk_lock.slock);
2398 if (sk->sk_backlog.tail)
2399 __release_sock(sk);
2400
2401 /* Warning : release_cb() might need to release sk ownership,
2402 * ie call sock_release_ownership(sk) before us.
2403 */
2404 if (sk->sk_prot->release_cb)
2405 sk->sk_prot->release_cb(sk);
2406
2407 sock_release_ownership(sk);
2408 if (waitqueue_active(&sk->sk_lock.wq))
2409 wake_up(&sk->sk_lock.wq);
2410 spin_unlock_bh(&sk->sk_lock.slock);
2411 }
2412 EXPORT_SYMBOL(release_sock);
2413
2414 /**
2415 * lock_sock_fast - fast version of lock_sock
2416 * @sk: socket
2417 *
2418 * This version should be used for very small section, where process wont block
2419 * return false if fast path is taken
2420 * sk_lock.slock locked, owned = 0, BH disabled
2421 * return true if slow path is taken
2422 * sk_lock.slock unlocked, owned = 1, BH enabled
2423 */
2424 bool lock_sock_fast(struct sock *sk)
2425 {
2426 might_sleep();
2427 spin_lock_bh(&sk->sk_lock.slock);
2428
2429 if (!sk->sk_lock.owned)
2430 /*
2431 * Note : We must disable BH
2432 */
2433 return false;
2434
2435 __lock_sock(sk);
2436 sk->sk_lock.owned = 1;
2437 spin_unlock(&sk->sk_lock.slock);
2438 /*
2439 * The sk_lock has mutex_lock() semantics here:
2440 */
2441 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2442 local_bh_enable();
2443 return true;
2444 }
2445 EXPORT_SYMBOL(lock_sock_fast);
2446
2447 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2448 {
2449 struct timeval tv;
2450 if (!sock_flag(sk, SOCK_TIMESTAMP))
2451 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2452 tv = ktime_to_timeval(sk->sk_stamp);
2453 if (tv.tv_sec == -1)
2454 return -ENOENT;
2455 if (tv.tv_sec == 0) {
2456 sk->sk_stamp = ktime_get_real();
2457 tv = ktime_to_timeval(sk->sk_stamp);
2458 }
2459 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2460 }
2461 EXPORT_SYMBOL(sock_get_timestamp);
2462
2463 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2464 {
2465 struct timespec ts;
2466 if (!sock_flag(sk, SOCK_TIMESTAMP))
2467 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2468 ts = ktime_to_timespec(sk->sk_stamp);
2469 if (ts.tv_sec == -1)
2470 return -ENOENT;
2471 if (ts.tv_sec == 0) {
2472 sk->sk_stamp = ktime_get_real();
2473 ts = ktime_to_timespec(sk->sk_stamp);
2474 }
2475 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2476 }
2477 EXPORT_SYMBOL(sock_get_timestampns);
2478
2479 void sock_enable_timestamp(struct sock *sk, int flag)
2480 {
2481 if (!sock_flag(sk, flag)) {
2482 unsigned long previous_flags = sk->sk_flags;
2483
2484 sock_set_flag(sk, flag);
2485 /*
2486 * we just set one of the two flags which require net
2487 * time stamping, but time stamping might have been on
2488 * already because of the other one
2489 */
2490 if (!(previous_flags & SK_FLAGS_TIMESTAMP))
2491 net_enable_timestamp();
2492 }
2493 }
2494
2495 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2496 int level, int type)
2497 {
2498 struct sock_exterr_skb *serr;
2499 struct sk_buff *skb, *skb2;
2500 int copied, err;
2501
2502 err = -EAGAIN;
2503 skb = skb_dequeue(&sk->sk_error_queue);
2504 if (skb == NULL)
2505 goto out;
2506
2507 copied = skb->len;
2508 if (copied > len) {
2509 msg->msg_flags |= MSG_TRUNC;
2510 copied = len;
2511 }
2512 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
2513 if (err)
2514 goto out_free_skb;
2515
2516 sock_recv_timestamp(msg, sk, skb);
2517
2518 serr = SKB_EXT_ERR(skb);
2519 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2520
2521 msg->msg_flags |= MSG_ERRQUEUE;
2522 err = copied;
2523
2524 /* Reset and regenerate socket error */
2525 spin_lock_bh(&sk->sk_error_queue.lock);
2526 sk->sk_err = 0;
2527 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
2528 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
2529 spin_unlock_bh(&sk->sk_error_queue.lock);
2530 sk->sk_error_report(sk);
2531 } else
2532 spin_unlock_bh(&sk->sk_error_queue.lock);
2533
2534 out_free_skb:
2535 kfree_skb(skb);
2536 out:
2537 return err;
2538 }
2539 EXPORT_SYMBOL(sock_recv_errqueue);
2540
2541 /*
2542 * Get a socket option on an socket.
2543 *
2544 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2545 * asynchronous errors should be reported by getsockopt. We assume
2546 * this means if you specify SO_ERROR (otherwise whats the point of it).
2547 */
2548 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2549 char __user *optval, int __user *optlen)
2550 {
2551 struct sock *sk = sock->sk;
2552
2553 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2554 }
2555 EXPORT_SYMBOL(sock_common_getsockopt);
2556
2557 #ifdef CONFIG_COMPAT
2558 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2559 char __user *optval, int __user *optlen)
2560 {
2561 struct sock *sk = sock->sk;
2562
2563 if (sk->sk_prot->compat_getsockopt != NULL)
2564 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2565 optval, optlen);
2566 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2567 }
2568 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2569 #endif
2570
2571 int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock,
2572 struct msghdr *msg, size_t size, int flags)
2573 {
2574 struct sock *sk = sock->sk;
2575 int addr_len = 0;
2576 int err;
2577
2578 err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT,
2579 flags & ~MSG_DONTWAIT, &addr_len);
2580 if (err >= 0)
2581 msg->msg_namelen = addr_len;
2582 return err;
2583 }
2584 EXPORT_SYMBOL(sock_common_recvmsg);
2585
2586 /*
2587 * Set socket options on an inet socket.
2588 */
2589 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2590 char __user *optval, unsigned int optlen)
2591 {
2592 struct sock *sk = sock->sk;
2593
2594 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2595 }
2596 EXPORT_SYMBOL(sock_common_setsockopt);
2597
2598 #ifdef CONFIG_COMPAT
2599 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2600 char __user *optval, unsigned int optlen)
2601 {
2602 struct sock *sk = sock->sk;
2603
2604 if (sk->sk_prot->compat_setsockopt != NULL)
2605 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2606 optval, optlen);
2607 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2608 }
2609 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2610 #endif
2611
2612 void sk_common_release(struct sock *sk)
2613 {
2614 if (sk->sk_prot->destroy)
2615 sk->sk_prot->destroy(sk);
2616
2617 /*
2618 * Observation: when sock_common_release is called, processes have
2619 * no access to socket. But net still has.
2620 * Step one, detach it from networking:
2621 *
2622 * A. Remove from hash tables.
2623 */
2624
2625 sk->sk_prot->unhash(sk);
2626
2627 /*
2628 * In this point socket cannot receive new packets, but it is possible
2629 * that some packets are in flight because some CPU runs receiver and
2630 * did hash table lookup before we unhashed socket. They will achieve
2631 * receive queue and will be purged by socket destructor.
2632 *
2633 * Also we still have packets pending on receive queue and probably,
2634 * our own packets waiting in device queues. sock_destroy will drain
2635 * receive queue, but transmitted packets will delay socket destruction
2636 * until the last reference will be released.
2637 */
2638
2639 sock_orphan(sk);
2640
2641 xfrm_sk_free_policy(sk);
2642
2643 sk_refcnt_debug_release(sk);
2644
2645 if (sk->sk_frag.page) {
2646 put_page(sk->sk_frag.page);
2647 sk->sk_frag.page = NULL;
2648 }
2649
2650 sock_put(sk);
2651 }
2652 EXPORT_SYMBOL(sk_common_release);
2653
2654 #ifdef CONFIG_PROC_FS
2655 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
2656 struct prot_inuse {
2657 int val[PROTO_INUSE_NR];
2658 };
2659
2660 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2661
2662 #ifdef CONFIG_NET_NS
2663 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2664 {
2665 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2666 }
2667 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2668
2669 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2670 {
2671 int cpu, idx = prot->inuse_idx;
2672 int res = 0;
2673
2674 for_each_possible_cpu(cpu)
2675 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2676
2677 return res >= 0 ? res : 0;
2678 }
2679 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2680
2681 static int __net_init sock_inuse_init_net(struct net *net)
2682 {
2683 net->core.inuse = alloc_percpu(struct prot_inuse);
2684 return net->core.inuse ? 0 : -ENOMEM;
2685 }
2686
2687 static void __net_exit sock_inuse_exit_net(struct net *net)
2688 {
2689 free_percpu(net->core.inuse);
2690 }
2691
2692 static struct pernet_operations net_inuse_ops = {
2693 .init = sock_inuse_init_net,
2694 .exit = sock_inuse_exit_net,
2695 };
2696
2697 static __init int net_inuse_init(void)
2698 {
2699 if (register_pernet_subsys(&net_inuse_ops))
2700 panic("Cannot initialize net inuse counters");
2701
2702 return 0;
2703 }
2704
2705 core_initcall(net_inuse_init);
2706 #else
2707 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2708
2709 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2710 {
2711 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2712 }
2713 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2714
2715 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2716 {
2717 int cpu, idx = prot->inuse_idx;
2718 int res = 0;
2719
2720 for_each_possible_cpu(cpu)
2721 res += per_cpu(prot_inuse, cpu).val[idx];
2722
2723 return res >= 0 ? res : 0;
2724 }
2725 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2726 #endif
2727
2728 static void assign_proto_idx(struct proto *prot)
2729 {
2730 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2731
2732 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2733 pr_err("PROTO_INUSE_NR exhausted\n");
2734 return;
2735 }
2736
2737 set_bit(prot->inuse_idx, proto_inuse_idx);
2738 }
2739
2740 static void release_proto_idx(struct proto *prot)
2741 {
2742 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2743 clear_bit(prot->inuse_idx, proto_inuse_idx);
2744 }
2745 #else
2746 static inline void assign_proto_idx(struct proto *prot)
2747 {
2748 }
2749
2750 static inline void release_proto_idx(struct proto *prot)
2751 {
2752 }
2753 #endif
2754
2755 int proto_register(struct proto *prot, int alloc_slab)
2756 {
2757 if (alloc_slab) {
2758 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2759 SLAB_HWCACHE_ALIGN | prot->slab_flags,
2760 NULL);
2761
2762 if (prot->slab == NULL) {
2763 pr_crit("%s: Can't create sock SLAB cache!\n",
2764 prot->name);
2765 goto out;
2766 }
2767
2768 if (prot->rsk_prot != NULL) {
2769 prot->rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s", prot->name);
2770 if (prot->rsk_prot->slab_name == NULL)
2771 goto out_free_sock_slab;
2772
2773 prot->rsk_prot->slab = kmem_cache_create(prot->rsk_prot->slab_name,
2774 prot->rsk_prot->obj_size, 0,
2775 SLAB_HWCACHE_ALIGN, NULL);
2776
2777 if (prot->rsk_prot->slab == NULL) {
2778 pr_crit("%s: Can't create request sock SLAB cache!\n",
2779 prot->name);
2780 goto out_free_request_sock_slab_name;
2781 }
2782 }
2783
2784 if (prot->twsk_prot != NULL) {
2785 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2786
2787 if (prot->twsk_prot->twsk_slab_name == NULL)
2788 goto out_free_request_sock_slab;
2789
2790 prot->twsk_prot->twsk_slab =
2791 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2792 prot->twsk_prot->twsk_obj_size,
2793 0,
2794 SLAB_HWCACHE_ALIGN |
2795 prot->slab_flags,
2796 NULL);
2797 if (prot->twsk_prot->twsk_slab == NULL)
2798 goto out_free_timewait_sock_slab_name;
2799 }
2800 }
2801
2802 mutex_lock(&proto_list_mutex);
2803 list_add(&prot->node, &proto_list);
2804 assign_proto_idx(prot);
2805 mutex_unlock(&proto_list_mutex);
2806 return 0;
2807
2808 out_free_timewait_sock_slab_name:
2809 kfree(prot->twsk_prot->twsk_slab_name);
2810 out_free_request_sock_slab:
2811 if (prot->rsk_prot && prot->rsk_prot->slab) {
2812 kmem_cache_destroy(prot->rsk_prot->slab);
2813 prot->rsk_prot->slab = NULL;
2814 }
2815 out_free_request_sock_slab_name:
2816 if (prot->rsk_prot)
2817 kfree(prot->rsk_prot->slab_name);
2818 out_free_sock_slab:
2819 kmem_cache_destroy(prot->slab);
2820 prot->slab = NULL;
2821 out:
2822 return -ENOBUFS;
2823 }
2824 EXPORT_SYMBOL(proto_register);
2825
2826 void proto_unregister(struct proto *prot)
2827 {
2828 mutex_lock(&proto_list_mutex);
2829 release_proto_idx(prot);
2830 list_del(&prot->node);
2831 mutex_unlock(&proto_list_mutex);
2832
2833 if (prot->slab != NULL) {
2834 kmem_cache_destroy(prot->slab);
2835 prot->slab = NULL;
2836 }
2837
2838 if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) {
2839 kmem_cache_destroy(prot->rsk_prot->slab);
2840 kfree(prot->rsk_prot->slab_name);
2841 prot->rsk_prot->slab = NULL;
2842 }
2843
2844 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
2845 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
2846 kfree(prot->twsk_prot->twsk_slab_name);
2847 prot->twsk_prot->twsk_slab = NULL;
2848 }
2849 }
2850 EXPORT_SYMBOL(proto_unregister);
2851
2852 #ifdef CONFIG_PROC_FS
2853 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
2854 __acquires(proto_list_mutex)
2855 {
2856 mutex_lock(&proto_list_mutex);
2857 return seq_list_start_head(&proto_list, *pos);
2858 }
2859
2860 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2861 {
2862 return seq_list_next(v, &proto_list, pos);
2863 }
2864
2865 static void proto_seq_stop(struct seq_file *seq, void *v)
2866 __releases(proto_list_mutex)
2867 {
2868 mutex_unlock(&proto_list_mutex);
2869 }
2870
2871 static char proto_method_implemented(const void *method)
2872 {
2873 return method == NULL ? 'n' : 'y';
2874 }
2875 static long sock_prot_memory_allocated(struct proto *proto)
2876 {
2877 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
2878 }
2879
2880 static char *sock_prot_memory_pressure(struct proto *proto)
2881 {
2882 return proto->memory_pressure != NULL ?
2883 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
2884 }
2885
2886 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
2887 {
2888
2889 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
2890 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
2891 proto->name,
2892 proto->obj_size,
2893 sock_prot_inuse_get(seq_file_net(seq), proto),
2894 sock_prot_memory_allocated(proto),
2895 sock_prot_memory_pressure(proto),
2896 proto->max_header,
2897 proto->slab == NULL ? "no" : "yes",
2898 module_name(proto->owner),
2899 proto_method_implemented(proto->close),
2900 proto_method_implemented(proto->connect),
2901 proto_method_implemented(proto->disconnect),
2902 proto_method_implemented(proto->accept),
2903 proto_method_implemented(proto->ioctl),
2904 proto_method_implemented(proto->init),
2905 proto_method_implemented(proto->destroy),
2906 proto_method_implemented(proto->shutdown),
2907 proto_method_implemented(proto->setsockopt),
2908 proto_method_implemented(proto->getsockopt),
2909 proto_method_implemented(proto->sendmsg),
2910 proto_method_implemented(proto->recvmsg),
2911 proto_method_implemented(proto->sendpage),
2912 proto_method_implemented(proto->bind),
2913 proto_method_implemented(proto->backlog_rcv),
2914 proto_method_implemented(proto->hash),
2915 proto_method_implemented(proto->unhash),
2916 proto_method_implemented(proto->get_port),
2917 proto_method_implemented(proto->enter_memory_pressure));
2918 }
2919
2920 static int proto_seq_show(struct seq_file *seq, void *v)
2921 {
2922 if (v == &proto_list)
2923 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
2924 "protocol",
2925 "size",
2926 "sockets",
2927 "memory",
2928 "press",
2929 "maxhdr",
2930 "slab",
2931 "module",
2932 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
2933 else
2934 proto_seq_printf(seq, list_entry(v, struct proto, node));
2935 return 0;
2936 }
2937
2938 static const struct seq_operations proto_seq_ops = {
2939 .start = proto_seq_start,
2940 .next = proto_seq_next,
2941 .stop = proto_seq_stop,
2942 .show = proto_seq_show,
2943 };
2944
2945 static int proto_seq_open(struct inode *inode, struct file *file)
2946 {
2947 return seq_open_net(inode, file, &proto_seq_ops,
2948 sizeof(struct seq_net_private));
2949 }
2950
2951 static const struct file_operations proto_seq_fops = {
2952 .owner = THIS_MODULE,
2953 .open = proto_seq_open,
2954 .read = seq_read,
2955 .llseek = seq_lseek,
2956 .release = seq_release_net,
2957 };
2958
2959 static __net_init int proto_init_net(struct net *net)
2960 {
2961 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
2962 return -ENOMEM;
2963
2964 return 0;
2965 }
2966
2967 static __net_exit void proto_exit_net(struct net *net)
2968 {
2969 remove_proc_entry("protocols", net->proc_net);
2970 }
2971
2972
2973 static __net_initdata struct pernet_operations proto_net_ops = {
2974 .init = proto_init_net,
2975 .exit = proto_exit_net,
2976 };
2977
2978 static int __init proto_init(void)
2979 {
2980 return register_pernet_subsys(&proto_net_ops);
2981 }
2982
2983 subsys_initcall(proto_init);
2984
2985 #endif /* PROC_FS */
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