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Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa...
[mirror_ubuntu-bionic-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 <linux/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 #include <linux/sock_diag.h>
135
136 #include <linux/filter.h>
137 #include <net/sock_reuseport.h>
138
139 #include <trace/events/sock.h>
140
141 #ifdef CONFIG_INET
142 #include <net/tcp.h>
143 #endif
144
145 #include <net/busy_poll.h>
146
147 static DEFINE_MUTEX(proto_list_mutex);
148 static LIST_HEAD(proto_list);
149
150 /**
151 * sk_ns_capable - General socket capability test
152 * @sk: Socket to use a capability on or through
153 * @user_ns: The user namespace of the capability to use
154 * @cap: The capability to use
155 *
156 * Test to see if the opener of the socket had when the socket was
157 * created and the current process has the capability @cap in the user
158 * namespace @user_ns.
159 */
160 bool sk_ns_capable(const struct sock *sk,
161 struct user_namespace *user_ns, int cap)
162 {
163 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
164 ns_capable(user_ns, cap);
165 }
166 EXPORT_SYMBOL(sk_ns_capable);
167
168 /**
169 * sk_capable - Socket global capability test
170 * @sk: Socket to use a capability on or through
171 * @cap: The global capability to use
172 *
173 * Test to see if the opener of the socket had when the socket was
174 * created and the current process has the capability @cap in all user
175 * namespaces.
176 */
177 bool sk_capable(const struct sock *sk, int cap)
178 {
179 return sk_ns_capable(sk, &init_user_ns, cap);
180 }
181 EXPORT_SYMBOL(sk_capable);
182
183 /**
184 * sk_net_capable - Network namespace socket capability test
185 * @sk: Socket to use a capability on or through
186 * @cap: The capability to use
187 *
188 * Test to see if the opener of the socket had when the socket was created
189 * and the current process has the capability @cap over the network namespace
190 * the socket is a member of.
191 */
192 bool sk_net_capable(const struct sock *sk, int cap)
193 {
194 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
195 }
196 EXPORT_SYMBOL(sk_net_capable);
197
198 /*
199 * Each address family might have different locking rules, so we have
200 * one slock key per address family and separate keys for internal and
201 * userspace sockets.
202 */
203 static struct lock_class_key af_family_keys[AF_MAX];
204 static struct lock_class_key af_family_kern_keys[AF_MAX];
205 static struct lock_class_key af_family_slock_keys[AF_MAX];
206 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
207
208 /*
209 * Make lock validator output more readable. (we pre-construct these
210 * strings build-time, so that runtime initialization of socket
211 * locks is fast):
212 */
213
214 #define _sock_locks(x) \
215 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \
216 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \
217 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \
218 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \
219 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \
220 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \
221 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \
222 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \
223 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \
224 x "27" , x "28" , x "AF_CAN" , \
225 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \
226 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \
227 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \
228 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \
229 x "AF_QIPCRTR", x "AF_SMC" , x "AF_MAX"
230
231 static const char *const af_family_key_strings[AF_MAX+1] = {
232 _sock_locks("sk_lock-")
233 };
234 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
235 _sock_locks("slock-")
236 };
237 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
238 _sock_locks("clock-")
239 };
240
241 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
242 _sock_locks("k-sk_lock-")
243 };
244 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
245 _sock_locks("k-slock-")
246 };
247 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
248 _sock_locks("k-clock-")
249 };
250
251 /*
252 * sk_callback_lock locking rules are per-address-family,
253 * so split the lock classes by using a per-AF key:
254 */
255 static struct lock_class_key af_callback_keys[AF_MAX];
256 static struct lock_class_key af_kern_callback_keys[AF_MAX];
257
258 /* Take into consideration the size of the struct sk_buff overhead in the
259 * determination of these values, since that is non-constant across
260 * platforms. This makes socket queueing behavior and performance
261 * not depend upon such differences.
262 */
263 #define _SK_MEM_PACKETS 256
264 #define _SK_MEM_OVERHEAD SKB_TRUESIZE(256)
265 #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
266 #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS)
267
268 /* Run time adjustable parameters. */
269 __u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
270 EXPORT_SYMBOL(sysctl_wmem_max);
271 __u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
272 EXPORT_SYMBOL(sysctl_rmem_max);
273 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
274 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
275
276 /* Maximal space eaten by iovec or ancillary data plus some space */
277 int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
278 EXPORT_SYMBOL(sysctl_optmem_max);
279
280 int sysctl_tstamp_allow_data __read_mostly = 1;
281
282 struct static_key memalloc_socks = STATIC_KEY_INIT_FALSE;
283 EXPORT_SYMBOL_GPL(memalloc_socks);
284
285 /**
286 * sk_set_memalloc - sets %SOCK_MEMALLOC
287 * @sk: socket to set it on
288 *
289 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
290 * It's the responsibility of the admin to adjust min_free_kbytes
291 * to meet the requirements
292 */
293 void sk_set_memalloc(struct sock *sk)
294 {
295 sock_set_flag(sk, SOCK_MEMALLOC);
296 sk->sk_allocation |= __GFP_MEMALLOC;
297 static_key_slow_inc(&memalloc_socks);
298 }
299 EXPORT_SYMBOL_GPL(sk_set_memalloc);
300
301 void sk_clear_memalloc(struct sock *sk)
302 {
303 sock_reset_flag(sk, SOCK_MEMALLOC);
304 sk->sk_allocation &= ~__GFP_MEMALLOC;
305 static_key_slow_dec(&memalloc_socks);
306
307 /*
308 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
309 * progress of swapping. SOCK_MEMALLOC may be cleared while
310 * it has rmem allocations due to the last swapfile being deactivated
311 * but there is a risk that the socket is unusable due to exceeding
312 * the rmem limits. Reclaim the reserves and obey rmem limits again.
313 */
314 sk_mem_reclaim(sk);
315 }
316 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
317
318 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
319 {
320 int ret;
321 unsigned long pflags = current->flags;
322
323 /* these should have been dropped before queueing */
324 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
325
326 current->flags |= PF_MEMALLOC;
327 ret = sk->sk_backlog_rcv(sk, skb);
328 tsk_restore_flags(current, pflags, PF_MEMALLOC);
329
330 return ret;
331 }
332 EXPORT_SYMBOL(__sk_backlog_rcv);
333
334 static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen)
335 {
336 struct timeval tv;
337
338 if (optlen < sizeof(tv))
339 return -EINVAL;
340 if (copy_from_user(&tv, optval, sizeof(tv)))
341 return -EFAULT;
342 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
343 return -EDOM;
344
345 if (tv.tv_sec < 0) {
346 static int warned __read_mostly;
347
348 *timeo_p = 0;
349 if (warned < 10 && net_ratelimit()) {
350 warned++;
351 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
352 __func__, current->comm, task_pid_nr(current));
353 }
354 return 0;
355 }
356 *timeo_p = MAX_SCHEDULE_TIMEOUT;
357 if (tv.tv_sec == 0 && tv.tv_usec == 0)
358 return 0;
359 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1))
360 *timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP(tv.tv_usec, USEC_PER_SEC / HZ);
361 return 0;
362 }
363
364 static void sock_warn_obsolete_bsdism(const char *name)
365 {
366 static int warned;
367 static char warncomm[TASK_COMM_LEN];
368 if (strcmp(warncomm, current->comm) && warned < 5) {
369 strcpy(warncomm, current->comm);
370 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
371 warncomm, name);
372 warned++;
373 }
374 }
375
376 static bool sock_needs_netstamp(const struct sock *sk)
377 {
378 switch (sk->sk_family) {
379 case AF_UNSPEC:
380 case AF_UNIX:
381 return false;
382 default:
383 return true;
384 }
385 }
386
387 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
388 {
389 if (sk->sk_flags & flags) {
390 sk->sk_flags &= ~flags;
391 if (sock_needs_netstamp(sk) &&
392 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
393 net_disable_timestamp();
394 }
395 }
396
397
398 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
399 {
400 unsigned long flags;
401 struct sk_buff_head *list = &sk->sk_receive_queue;
402
403 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
404 atomic_inc(&sk->sk_drops);
405 trace_sock_rcvqueue_full(sk, skb);
406 return -ENOMEM;
407 }
408
409 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
410 atomic_inc(&sk->sk_drops);
411 return -ENOBUFS;
412 }
413
414 skb->dev = NULL;
415 skb_set_owner_r(skb, sk);
416
417 /* we escape from rcu protected region, make sure we dont leak
418 * a norefcounted dst
419 */
420 skb_dst_force(skb);
421
422 spin_lock_irqsave(&list->lock, flags);
423 sock_skb_set_dropcount(sk, skb);
424 __skb_queue_tail(list, skb);
425 spin_unlock_irqrestore(&list->lock, flags);
426
427 if (!sock_flag(sk, SOCK_DEAD))
428 sk->sk_data_ready(sk);
429 return 0;
430 }
431 EXPORT_SYMBOL(__sock_queue_rcv_skb);
432
433 int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
434 {
435 int err;
436
437 err = sk_filter(sk, skb);
438 if (err)
439 return err;
440
441 return __sock_queue_rcv_skb(sk, skb);
442 }
443 EXPORT_SYMBOL(sock_queue_rcv_skb);
444
445 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
446 const int nested, unsigned int trim_cap, bool refcounted)
447 {
448 int rc = NET_RX_SUCCESS;
449
450 if (sk_filter_trim_cap(sk, skb, trim_cap))
451 goto discard_and_relse;
452
453 skb->dev = NULL;
454
455 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
456 atomic_inc(&sk->sk_drops);
457 goto discard_and_relse;
458 }
459 if (nested)
460 bh_lock_sock_nested(sk);
461 else
462 bh_lock_sock(sk);
463 if (!sock_owned_by_user(sk)) {
464 /*
465 * trylock + unlock semantics:
466 */
467 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
468
469 rc = sk_backlog_rcv(sk, skb);
470
471 mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_);
472 } else if (sk_add_backlog(sk, skb, sk->sk_rcvbuf)) {
473 bh_unlock_sock(sk);
474 atomic_inc(&sk->sk_drops);
475 goto discard_and_relse;
476 }
477
478 bh_unlock_sock(sk);
479 out:
480 if (refcounted)
481 sock_put(sk);
482 return rc;
483 discard_and_relse:
484 kfree_skb(skb);
485 goto out;
486 }
487 EXPORT_SYMBOL(__sk_receive_skb);
488
489 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
490 {
491 struct dst_entry *dst = __sk_dst_get(sk);
492
493 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
494 sk_tx_queue_clear(sk);
495 sk->sk_dst_pending_confirm = 0;
496 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
497 dst_release(dst);
498 return NULL;
499 }
500
501 return dst;
502 }
503 EXPORT_SYMBOL(__sk_dst_check);
504
505 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
506 {
507 struct dst_entry *dst = sk_dst_get(sk);
508
509 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
510 sk_dst_reset(sk);
511 dst_release(dst);
512 return NULL;
513 }
514
515 return dst;
516 }
517 EXPORT_SYMBOL(sk_dst_check);
518
519 static int sock_setbindtodevice(struct sock *sk, char __user *optval,
520 int optlen)
521 {
522 int ret = -ENOPROTOOPT;
523 #ifdef CONFIG_NETDEVICES
524 struct net *net = sock_net(sk);
525 char devname[IFNAMSIZ];
526 int index;
527
528 /* Sorry... */
529 ret = -EPERM;
530 if (!ns_capable(net->user_ns, CAP_NET_RAW))
531 goto out;
532
533 ret = -EINVAL;
534 if (optlen < 0)
535 goto out;
536
537 /* Bind this socket to a particular device like "eth0",
538 * as specified in the passed interface name. If the
539 * name is "" or the option length is zero the socket
540 * is not bound.
541 */
542 if (optlen > IFNAMSIZ - 1)
543 optlen = IFNAMSIZ - 1;
544 memset(devname, 0, sizeof(devname));
545
546 ret = -EFAULT;
547 if (copy_from_user(devname, optval, optlen))
548 goto out;
549
550 index = 0;
551 if (devname[0] != '\0') {
552 struct net_device *dev;
553
554 rcu_read_lock();
555 dev = dev_get_by_name_rcu(net, devname);
556 if (dev)
557 index = dev->ifindex;
558 rcu_read_unlock();
559 ret = -ENODEV;
560 if (!dev)
561 goto out;
562 }
563
564 lock_sock(sk);
565 sk->sk_bound_dev_if = index;
566 sk_dst_reset(sk);
567 release_sock(sk);
568
569 ret = 0;
570
571 out:
572 #endif
573
574 return ret;
575 }
576
577 static int sock_getbindtodevice(struct sock *sk, char __user *optval,
578 int __user *optlen, int len)
579 {
580 int ret = -ENOPROTOOPT;
581 #ifdef CONFIG_NETDEVICES
582 struct net *net = sock_net(sk);
583 char devname[IFNAMSIZ];
584
585 if (sk->sk_bound_dev_if == 0) {
586 len = 0;
587 goto zero;
588 }
589
590 ret = -EINVAL;
591 if (len < IFNAMSIZ)
592 goto out;
593
594 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
595 if (ret)
596 goto out;
597
598 len = strlen(devname) + 1;
599
600 ret = -EFAULT;
601 if (copy_to_user(optval, devname, len))
602 goto out;
603
604 zero:
605 ret = -EFAULT;
606 if (put_user(len, optlen))
607 goto out;
608
609 ret = 0;
610
611 out:
612 #endif
613
614 return ret;
615 }
616
617 static inline void sock_valbool_flag(struct sock *sk, int bit, int valbool)
618 {
619 if (valbool)
620 sock_set_flag(sk, bit);
621 else
622 sock_reset_flag(sk, bit);
623 }
624
625 bool sk_mc_loop(struct sock *sk)
626 {
627 if (dev_recursion_level())
628 return false;
629 if (!sk)
630 return true;
631 switch (sk->sk_family) {
632 case AF_INET:
633 return inet_sk(sk)->mc_loop;
634 #if IS_ENABLED(CONFIG_IPV6)
635 case AF_INET6:
636 return inet6_sk(sk)->mc_loop;
637 #endif
638 }
639 WARN_ON(1);
640 return true;
641 }
642 EXPORT_SYMBOL(sk_mc_loop);
643
644 /*
645 * This is meant for all protocols to use and covers goings on
646 * at the socket level. Everything here is generic.
647 */
648
649 int sock_setsockopt(struct socket *sock, int level, int optname,
650 char __user *optval, unsigned int optlen)
651 {
652 struct sock *sk = sock->sk;
653 int val;
654 int valbool;
655 struct linger ling;
656 int ret = 0;
657
658 /*
659 * Options without arguments
660 */
661
662 if (optname == SO_BINDTODEVICE)
663 return sock_setbindtodevice(sk, optval, optlen);
664
665 if (optlen < sizeof(int))
666 return -EINVAL;
667
668 if (get_user(val, (int __user *)optval))
669 return -EFAULT;
670
671 valbool = val ? 1 : 0;
672
673 lock_sock(sk);
674
675 switch (optname) {
676 case SO_DEBUG:
677 if (val && !capable(CAP_NET_ADMIN))
678 ret = -EACCES;
679 else
680 sock_valbool_flag(sk, SOCK_DBG, valbool);
681 break;
682 case SO_REUSEADDR:
683 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
684 break;
685 case SO_REUSEPORT:
686 sk->sk_reuseport = valbool;
687 break;
688 case SO_TYPE:
689 case SO_PROTOCOL:
690 case SO_DOMAIN:
691 case SO_ERROR:
692 ret = -ENOPROTOOPT;
693 break;
694 case SO_DONTROUTE:
695 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
696 break;
697 case SO_BROADCAST:
698 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
699 break;
700 case SO_SNDBUF:
701 /* Don't error on this BSD doesn't and if you think
702 * about it this is right. Otherwise apps have to
703 * play 'guess the biggest size' games. RCVBUF/SNDBUF
704 * are treated in BSD as hints
705 */
706 val = min_t(u32, val, sysctl_wmem_max);
707 set_sndbuf:
708 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
709 sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
710 /* Wake up sending tasks if we upped the value. */
711 sk->sk_write_space(sk);
712 break;
713
714 case SO_SNDBUFFORCE:
715 if (!capable(CAP_NET_ADMIN)) {
716 ret = -EPERM;
717 break;
718 }
719 goto set_sndbuf;
720
721 case SO_RCVBUF:
722 /* Don't error on this BSD doesn't and if you think
723 * about it this is right. Otherwise apps have to
724 * play 'guess the biggest size' games. RCVBUF/SNDBUF
725 * are treated in BSD as hints
726 */
727 val = min_t(u32, val, sysctl_rmem_max);
728 set_rcvbuf:
729 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
730 /*
731 * We double it on the way in to account for
732 * "struct sk_buff" etc. overhead. Applications
733 * assume that the SO_RCVBUF setting they make will
734 * allow that much actual data to be received on that
735 * socket.
736 *
737 * Applications are unaware that "struct sk_buff" and
738 * other overheads allocate from the receive buffer
739 * during socket buffer allocation.
740 *
741 * And after considering the possible alternatives,
742 * returning the value we actually used in getsockopt
743 * is the most desirable behavior.
744 */
745 sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
746 break;
747
748 case SO_RCVBUFFORCE:
749 if (!capable(CAP_NET_ADMIN)) {
750 ret = -EPERM;
751 break;
752 }
753 goto set_rcvbuf;
754
755 case SO_KEEPALIVE:
756 if (sk->sk_prot->keepalive)
757 sk->sk_prot->keepalive(sk, valbool);
758 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
759 break;
760
761 case SO_OOBINLINE:
762 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
763 break;
764
765 case SO_NO_CHECK:
766 sk->sk_no_check_tx = valbool;
767 break;
768
769 case SO_PRIORITY:
770 if ((val >= 0 && val <= 6) ||
771 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
772 sk->sk_priority = val;
773 else
774 ret = -EPERM;
775 break;
776
777 case SO_LINGER:
778 if (optlen < sizeof(ling)) {
779 ret = -EINVAL; /* 1003.1g */
780 break;
781 }
782 if (copy_from_user(&ling, optval, sizeof(ling))) {
783 ret = -EFAULT;
784 break;
785 }
786 if (!ling.l_onoff)
787 sock_reset_flag(sk, SOCK_LINGER);
788 else {
789 #if (BITS_PER_LONG == 32)
790 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
791 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
792 else
793 #endif
794 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
795 sock_set_flag(sk, SOCK_LINGER);
796 }
797 break;
798
799 case SO_BSDCOMPAT:
800 sock_warn_obsolete_bsdism("setsockopt");
801 break;
802
803 case SO_PASSCRED:
804 if (valbool)
805 set_bit(SOCK_PASSCRED, &sock->flags);
806 else
807 clear_bit(SOCK_PASSCRED, &sock->flags);
808 break;
809
810 case SO_TIMESTAMP:
811 case SO_TIMESTAMPNS:
812 if (valbool) {
813 if (optname == SO_TIMESTAMP)
814 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
815 else
816 sock_set_flag(sk, SOCK_RCVTSTAMPNS);
817 sock_set_flag(sk, SOCK_RCVTSTAMP);
818 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
819 } else {
820 sock_reset_flag(sk, SOCK_RCVTSTAMP);
821 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
822 }
823 break;
824
825 case SO_TIMESTAMPING:
826 if (val & ~SOF_TIMESTAMPING_MASK) {
827 ret = -EINVAL;
828 break;
829 }
830
831 if (val & SOF_TIMESTAMPING_OPT_ID &&
832 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
833 if (sk->sk_protocol == IPPROTO_TCP &&
834 sk->sk_type == SOCK_STREAM) {
835 if ((1 << sk->sk_state) &
836 (TCPF_CLOSE | TCPF_LISTEN)) {
837 ret = -EINVAL;
838 break;
839 }
840 sk->sk_tskey = tcp_sk(sk)->snd_una;
841 } else {
842 sk->sk_tskey = 0;
843 }
844 }
845
846 if (val & SOF_TIMESTAMPING_OPT_STATS &&
847 !(val & SOF_TIMESTAMPING_OPT_TSONLY)) {
848 ret = -EINVAL;
849 break;
850 }
851
852 sk->sk_tsflags = val;
853 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
854 sock_enable_timestamp(sk,
855 SOCK_TIMESTAMPING_RX_SOFTWARE);
856 else
857 sock_disable_timestamp(sk,
858 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
859 break;
860
861 case SO_RCVLOWAT:
862 if (val < 0)
863 val = INT_MAX;
864 sk->sk_rcvlowat = val ? : 1;
865 break;
866
867 case SO_RCVTIMEO:
868 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen);
869 break;
870
871 case SO_SNDTIMEO:
872 ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen);
873 break;
874
875 case SO_ATTACH_FILTER:
876 ret = -EINVAL;
877 if (optlen == sizeof(struct sock_fprog)) {
878 struct sock_fprog fprog;
879
880 ret = -EFAULT;
881 if (copy_from_user(&fprog, optval, sizeof(fprog)))
882 break;
883
884 ret = sk_attach_filter(&fprog, sk);
885 }
886 break;
887
888 case SO_ATTACH_BPF:
889 ret = -EINVAL;
890 if (optlen == sizeof(u32)) {
891 u32 ufd;
892
893 ret = -EFAULT;
894 if (copy_from_user(&ufd, optval, sizeof(ufd)))
895 break;
896
897 ret = sk_attach_bpf(ufd, sk);
898 }
899 break;
900
901 case SO_ATTACH_REUSEPORT_CBPF:
902 ret = -EINVAL;
903 if (optlen == sizeof(struct sock_fprog)) {
904 struct sock_fprog fprog;
905
906 ret = -EFAULT;
907 if (copy_from_user(&fprog, optval, sizeof(fprog)))
908 break;
909
910 ret = sk_reuseport_attach_filter(&fprog, sk);
911 }
912 break;
913
914 case SO_ATTACH_REUSEPORT_EBPF:
915 ret = -EINVAL;
916 if (optlen == sizeof(u32)) {
917 u32 ufd;
918
919 ret = -EFAULT;
920 if (copy_from_user(&ufd, optval, sizeof(ufd)))
921 break;
922
923 ret = sk_reuseport_attach_bpf(ufd, sk);
924 }
925 break;
926
927 case SO_DETACH_FILTER:
928 ret = sk_detach_filter(sk);
929 break;
930
931 case SO_LOCK_FILTER:
932 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
933 ret = -EPERM;
934 else
935 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
936 break;
937
938 case SO_PASSSEC:
939 if (valbool)
940 set_bit(SOCK_PASSSEC, &sock->flags);
941 else
942 clear_bit(SOCK_PASSSEC, &sock->flags);
943 break;
944 case SO_MARK:
945 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
946 ret = -EPERM;
947 else
948 sk->sk_mark = val;
949 break;
950
951 case SO_RXQ_OVFL:
952 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
953 break;
954
955 case SO_WIFI_STATUS:
956 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
957 break;
958
959 case SO_PEEK_OFF:
960 if (sock->ops->set_peek_off)
961 ret = sock->ops->set_peek_off(sk, val);
962 else
963 ret = -EOPNOTSUPP;
964 break;
965
966 case SO_NOFCS:
967 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
968 break;
969
970 case SO_SELECT_ERR_QUEUE:
971 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
972 break;
973
974 #ifdef CONFIG_NET_RX_BUSY_POLL
975 case SO_BUSY_POLL:
976 /* allow unprivileged users to decrease the value */
977 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
978 ret = -EPERM;
979 else {
980 if (val < 0)
981 ret = -EINVAL;
982 else
983 sk->sk_ll_usec = val;
984 }
985 break;
986 #endif
987
988 case SO_MAX_PACING_RATE:
989 sk->sk_max_pacing_rate = val;
990 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
991 sk->sk_max_pacing_rate);
992 break;
993
994 case SO_INCOMING_CPU:
995 sk->sk_incoming_cpu = val;
996 break;
997
998 case SO_CNX_ADVICE:
999 if (val == 1)
1000 dst_negative_advice(sk);
1001 break;
1002 default:
1003 ret = -ENOPROTOOPT;
1004 break;
1005 }
1006 release_sock(sk);
1007 return ret;
1008 }
1009 EXPORT_SYMBOL(sock_setsockopt);
1010
1011
1012 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1013 struct ucred *ucred)
1014 {
1015 ucred->pid = pid_vnr(pid);
1016 ucred->uid = ucred->gid = -1;
1017 if (cred) {
1018 struct user_namespace *current_ns = current_user_ns();
1019
1020 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1021 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1022 }
1023 }
1024
1025 int sock_getsockopt(struct socket *sock, int level, int optname,
1026 char __user *optval, int __user *optlen)
1027 {
1028 struct sock *sk = sock->sk;
1029
1030 union {
1031 int val;
1032 struct linger ling;
1033 struct timeval tm;
1034 } v;
1035
1036 int lv = sizeof(int);
1037 int len;
1038
1039 if (get_user(len, optlen))
1040 return -EFAULT;
1041 if (len < 0)
1042 return -EINVAL;
1043
1044 memset(&v, 0, sizeof(v));
1045
1046 switch (optname) {
1047 case SO_DEBUG:
1048 v.val = sock_flag(sk, SOCK_DBG);
1049 break;
1050
1051 case SO_DONTROUTE:
1052 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1053 break;
1054
1055 case SO_BROADCAST:
1056 v.val = sock_flag(sk, SOCK_BROADCAST);
1057 break;
1058
1059 case SO_SNDBUF:
1060 v.val = sk->sk_sndbuf;
1061 break;
1062
1063 case SO_RCVBUF:
1064 v.val = sk->sk_rcvbuf;
1065 break;
1066
1067 case SO_REUSEADDR:
1068 v.val = sk->sk_reuse;
1069 break;
1070
1071 case SO_REUSEPORT:
1072 v.val = sk->sk_reuseport;
1073 break;
1074
1075 case SO_KEEPALIVE:
1076 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1077 break;
1078
1079 case SO_TYPE:
1080 v.val = sk->sk_type;
1081 break;
1082
1083 case SO_PROTOCOL:
1084 v.val = sk->sk_protocol;
1085 break;
1086
1087 case SO_DOMAIN:
1088 v.val = sk->sk_family;
1089 break;
1090
1091 case SO_ERROR:
1092 v.val = -sock_error(sk);
1093 if (v.val == 0)
1094 v.val = xchg(&sk->sk_err_soft, 0);
1095 break;
1096
1097 case SO_OOBINLINE:
1098 v.val = sock_flag(sk, SOCK_URGINLINE);
1099 break;
1100
1101 case SO_NO_CHECK:
1102 v.val = sk->sk_no_check_tx;
1103 break;
1104
1105 case SO_PRIORITY:
1106 v.val = sk->sk_priority;
1107 break;
1108
1109 case SO_LINGER:
1110 lv = sizeof(v.ling);
1111 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1112 v.ling.l_linger = sk->sk_lingertime / HZ;
1113 break;
1114
1115 case SO_BSDCOMPAT:
1116 sock_warn_obsolete_bsdism("getsockopt");
1117 break;
1118
1119 case SO_TIMESTAMP:
1120 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1121 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1122 break;
1123
1124 case SO_TIMESTAMPNS:
1125 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS);
1126 break;
1127
1128 case SO_TIMESTAMPING:
1129 v.val = sk->sk_tsflags;
1130 break;
1131
1132 case SO_RCVTIMEO:
1133 lv = sizeof(struct timeval);
1134 if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) {
1135 v.tm.tv_sec = 0;
1136 v.tm.tv_usec = 0;
1137 } else {
1138 v.tm.tv_sec = sk->sk_rcvtimeo / HZ;
1139 v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * USEC_PER_SEC) / HZ;
1140 }
1141 break;
1142
1143 case SO_SNDTIMEO:
1144 lv = sizeof(struct timeval);
1145 if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) {
1146 v.tm.tv_sec = 0;
1147 v.tm.tv_usec = 0;
1148 } else {
1149 v.tm.tv_sec = sk->sk_sndtimeo / HZ;
1150 v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * USEC_PER_SEC) / HZ;
1151 }
1152 break;
1153
1154 case SO_RCVLOWAT:
1155 v.val = sk->sk_rcvlowat;
1156 break;
1157
1158 case SO_SNDLOWAT:
1159 v.val = 1;
1160 break;
1161
1162 case SO_PASSCRED:
1163 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1164 break;
1165
1166 case SO_PEERCRED:
1167 {
1168 struct ucred peercred;
1169 if (len > sizeof(peercred))
1170 len = sizeof(peercred);
1171 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1172 if (copy_to_user(optval, &peercred, len))
1173 return -EFAULT;
1174 goto lenout;
1175 }
1176
1177 case SO_PEERNAME:
1178 {
1179 char address[128];
1180
1181 if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2))
1182 return -ENOTCONN;
1183 if (lv < len)
1184 return -EINVAL;
1185 if (copy_to_user(optval, address, len))
1186 return -EFAULT;
1187 goto lenout;
1188 }
1189
1190 /* Dubious BSD thing... Probably nobody even uses it, but
1191 * the UNIX standard wants it for whatever reason... -DaveM
1192 */
1193 case SO_ACCEPTCONN:
1194 v.val = sk->sk_state == TCP_LISTEN;
1195 break;
1196
1197 case SO_PASSSEC:
1198 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1199 break;
1200
1201 case SO_PEERSEC:
1202 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1203
1204 case SO_MARK:
1205 v.val = sk->sk_mark;
1206 break;
1207
1208 case SO_RXQ_OVFL:
1209 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1210 break;
1211
1212 case SO_WIFI_STATUS:
1213 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1214 break;
1215
1216 case SO_PEEK_OFF:
1217 if (!sock->ops->set_peek_off)
1218 return -EOPNOTSUPP;
1219
1220 v.val = sk->sk_peek_off;
1221 break;
1222 case SO_NOFCS:
1223 v.val = sock_flag(sk, SOCK_NOFCS);
1224 break;
1225
1226 case SO_BINDTODEVICE:
1227 return sock_getbindtodevice(sk, optval, optlen, len);
1228
1229 case SO_GET_FILTER:
1230 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1231 if (len < 0)
1232 return len;
1233
1234 goto lenout;
1235
1236 case SO_LOCK_FILTER:
1237 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1238 break;
1239
1240 case SO_BPF_EXTENSIONS:
1241 v.val = bpf_tell_extensions();
1242 break;
1243
1244 case SO_SELECT_ERR_QUEUE:
1245 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1246 break;
1247
1248 #ifdef CONFIG_NET_RX_BUSY_POLL
1249 case SO_BUSY_POLL:
1250 v.val = sk->sk_ll_usec;
1251 break;
1252 #endif
1253
1254 case SO_MAX_PACING_RATE:
1255 v.val = sk->sk_max_pacing_rate;
1256 break;
1257
1258 case SO_INCOMING_CPU:
1259 v.val = sk->sk_incoming_cpu;
1260 break;
1261
1262 default:
1263 /* We implement the SO_SNDLOWAT etc to not be settable
1264 * (1003.1g 7).
1265 */
1266 return -ENOPROTOOPT;
1267 }
1268
1269 if (len > lv)
1270 len = lv;
1271 if (copy_to_user(optval, &v, len))
1272 return -EFAULT;
1273 lenout:
1274 if (put_user(len, optlen))
1275 return -EFAULT;
1276 return 0;
1277 }
1278
1279 /*
1280 * Initialize an sk_lock.
1281 *
1282 * (We also register the sk_lock with the lock validator.)
1283 */
1284 static inline void sock_lock_init(struct sock *sk)
1285 {
1286 if (sk->sk_kern_sock)
1287 sock_lock_init_class_and_name(
1288 sk,
1289 af_family_kern_slock_key_strings[sk->sk_family],
1290 af_family_kern_slock_keys + sk->sk_family,
1291 af_family_kern_key_strings[sk->sk_family],
1292 af_family_kern_keys + sk->sk_family);
1293 else
1294 sock_lock_init_class_and_name(
1295 sk,
1296 af_family_slock_key_strings[sk->sk_family],
1297 af_family_slock_keys + sk->sk_family,
1298 af_family_key_strings[sk->sk_family],
1299 af_family_keys + sk->sk_family);
1300 }
1301
1302 /*
1303 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1304 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1305 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1306 */
1307 static void sock_copy(struct sock *nsk, const struct sock *osk)
1308 {
1309 #ifdef CONFIG_SECURITY_NETWORK
1310 void *sptr = nsk->sk_security;
1311 #endif
1312 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1313
1314 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1315 osk->sk_prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1316
1317 #ifdef CONFIG_SECURITY_NETWORK
1318 nsk->sk_security = sptr;
1319 security_sk_clone(osk, nsk);
1320 #endif
1321 }
1322
1323 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1324 int family)
1325 {
1326 struct sock *sk;
1327 struct kmem_cache *slab;
1328
1329 slab = prot->slab;
1330 if (slab != NULL) {
1331 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1332 if (!sk)
1333 return sk;
1334 if (priority & __GFP_ZERO)
1335 sk_prot_clear_nulls(sk, prot->obj_size);
1336 } else
1337 sk = kmalloc(prot->obj_size, priority);
1338
1339 if (sk != NULL) {
1340 kmemcheck_annotate_bitfield(sk, flags);
1341
1342 if (security_sk_alloc(sk, family, priority))
1343 goto out_free;
1344
1345 if (!try_module_get(prot->owner))
1346 goto out_free_sec;
1347 sk_tx_queue_clear(sk);
1348 }
1349
1350 return sk;
1351
1352 out_free_sec:
1353 security_sk_free(sk);
1354 out_free:
1355 if (slab != NULL)
1356 kmem_cache_free(slab, sk);
1357 else
1358 kfree(sk);
1359 return NULL;
1360 }
1361
1362 static void sk_prot_free(struct proto *prot, struct sock *sk)
1363 {
1364 struct kmem_cache *slab;
1365 struct module *owner;
1366
1367 owner = prot->owner;
1368 slab = prot->slab;
1369
1370 cgroup_sk_free(&sk->sk_cgrp_data);
1371 mem_cgroup_sk_free(sk);
1372 security_sk_free(sk);
1373 if (slab != NULL)
1374 kmem_cache_free(slab, sk);
1375 else
1376 kfree(sk);
1377 module_put(owner);
1378 }
1379
1380 /**
1381 * sk_alloc - All socket objects are allocated here
1382 * @net: the applicable net namespace
1383 * @family: protocol family
1384 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1385 * @prot: struct proto associated with this new sock instance
1386 * @kern: is this to be a kernel socket?
1387 */
1388 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1389 struct proto *prot, int kern)
1390 {
1391 struct sock *sk;
1392
1393 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1394 if (sk) {
1395 sk->sk_family = family;
1396 /*
1397 * See comment in struct sock definition to understand
1398 * why we need sk_prot_creator -acme
1399 */
1400 sk->sk_prot = sk->sk_prot_creator = prot;
1401 sk->sk_kern_sock = kern;
1402 sock_lock_init(sk);
1403 sk->sk_net_refcnt = kern ? 0 : 1;
1404 if (likely(sk->sk_net_refcnt))
1405 get_net(net);
1406 sock_net_set(sk, net);
1407 atomic_set(&sk->sk_wmem_alloc, 1);
1408
1409 mem_cgroup_sk_alloc(sk);
1410 cgroup_sk_alloc(&sk->sk_cgrp_data);
1411 sock_update_classid(&sk->sk_cgrp_data);
1412 sock_update_netprioidx(&sk->sk_cgrp_data);
1413 }
1414
1415 return sk;
1416 }
1417 EXPORT_SYMBOL(sk_alloc);
1418
1419 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
1420 * grace period. This is the case for UDP sockets and TCP listeners.
1421 */
1422 static void __sk_destruct(struct rcu_head *head)
1423 {
1424 struct sock *sk = container_of(head, struct sock, sk_rcu);
1425 struct sk_filter *filter;
1426
1427 if (sk->sk_destruct)
1428 sk->sk_destruct(sk);
1429
1430 filter = rcu_dereference_check(sk->sk_filter,
1431 atomic_read(&sk->sk_wmem_alloc) == 0);
1432 if (filter) {
1433 sk_filter_uncharge(sk, filter);
1434 RCU_INIT_POINTER(sk->sk_filter, NULL);
1435 }
1436 if (rcu_access_pointer(sk->sk_reuseport_cb))
1437 reuseport_detach_sock(sk);
1438
1439 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1440
1441 if (atomic_read(&sk->sk_omem_alloc))
1442 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1443 __func__, atomic_read(&sk->sk_omem_alloc));
1444
1445 if (sk->sk_frag.page) {
1446 put_page(sk->sk_frag.page);
1447 sk->sk_frag.page = NULL;
1448 }
1449
1450 if (sk->sk_peer_cred)
1451 put_cred(sk->sk_peer_cred);
1452 put_pid(sk->sk_peer_pid);
1453 if (likely(sk->sk_net_refcnt))
1454 put_net(sock_net(sk));
1455 sk_prot_free(sk->sk_prot_creator, sk);
1456 }
1457
1458 void sk_destruct(struct sock *sk)
1459 {
1460 if (sock_flag(sk, SOCK_RCU_FREE))
1461 call_rcu(&sk->sk_rcu, __sk_destruct);
1462 else
1463 __sk_destruct(&sk->sk_rcu);
1464 }
1465
1466 static void __sk_free(struct sock *sk)
1467 {
1468 if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt))
1469 sock_diag_broadcast_destroy(sk);
1470 else
1471 sk_destruct(sk);
1472 }
1473
1474 void sk_free(struct sock *sk)
1475 {
1476 /*
1477 * We subtract one from sk_wmem_alloc and can know if
1478 * some packets are still in some tx queue.
1479 * If not null, sock_wfree() will call __sk_free(sk) later
1480 */
1481 if (atomic_dec_and_test(&sk->sk_wmem_alloc))
1482 __sk_free(sk);
1483 }
1484 EXPORT_SYMBOL(sk_free);
1485
1486 /**
1487 * sk_clone_lock - clone a socket, and lock its clone
1488 * @sk: the socket to clone
1489 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1490 *
1491 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1492 */
1493 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1494 {
1495 struct sock *newsk;
1496 bool is_charged = true;
1497
1498 newsk = sk_prot_alloc(sk->sk_prot, priority, sk->sk_family);
1499 if (newsk != NULL) {
1500 struct sk_filter *filter;
1501
1502 sock_copy(newsk, sk);
1503
1504 /* SANITY */
1505 if (likely(newsk->sk_net_refcnt))
1506 get_net(sock_net(newsk));
1507 sk_node_init(&newsk->sk_node);
1508 sock_lock_init(newsk);
1509 bh_lock_sock(newsk);
1510 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1511 newsk->sk_backlog.len = 0;
1512
1513 atomic_set(&newsk->sk_rmem_alloc, 0);
1514 /*
1515 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1516 */
1517 atomic_set(&newsk->sk_wmem_alloc, 1);
1518 atomic_set(&newsk->sk_omem_alloc, 0);
1519 skb_queue_head_init(&newsk->sk_receive_queue);
1520 skb_queue_head_init(&newsk->sk_write_queue);
1521
1522 rwlock_init(&newsk->sk_callback_lock);
1523 lockdep_set_class_and_name(&newsk->sk_callback_lock,
1524 af_callback_keys + newsk->sk_family,
1525 af_family_clock_key_strings[newsk->sk_family]);
1526
1527 newsk->sk_dst_cache = NULL;
1528 newsk->sk_dst_pending_confirm = 0;
1529 newsk->sk_wmem_queued = 0;
1530 newsk->sk_forward_alloc = 0;
1531 atomic_set(&newsk->sk_drops, 0);
1532 newsk->sk_send_head = NULL;
1533 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1534
1535 sock_reset_flag(newsk, SOCK_DONE);
1536 skb_queue_head_init(&newsk->sk_error_queue);
1537
1538 filter = rcu_dereference_protected(newsk->sk_filter, 1);
1539 if (filter != NULL)
1540 /* though it's an empty new sock, the charging may fail
1541 * if sysctl_optmem_max was changed between creation of
1542 * original socket and cloning
1543 */
1544 is_charged = sk_filter_charge(newsk, filter);
1545
1546 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1547 /* We need to make sure that we don't uncharge the new
1548 * socket if we couldn't charge it in the first place
1549 * as otherwise we uncharge the parent's filter.
1550 */
1551 if (!is_charged)
1552 RCU_INIT_POINTER(newsk->sk_filter, NULL);
1553 sk_free_unlock_clone(newsk);
1554 newsk = NULL;
1555 goto out;
1556 }
1557 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1558
1559 newsk->sk_err = 0;
1560 newsk->sk_err_soft = 0;
1561 newsk->sk_priority = 0;
1562 newsk->sk_incoming_cpu = raw_smp_processor_id();
1563 atomic64_set(&newsk->sk_cookie, 0);
1564
1565 mem_cgroup_sk_alloc(newsk);
1566 cgroup_sk_alloc(&newsk->sk_cgrp_data);
1567
1568 /*
1569 * Before updating sk_refcnt, we must commit prior changes to memory
1570 * (Documentation/RCU/rculist_nulls.txt for details)
1571 */
1572 smp_wmb();
1573 atomic_set(&newsk->sk_refcnt, 2);
1574
1575 /*
1576 * Increment the counter in the same struct proto as the master
1577 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1578 * is the same as sk->sk_prot->socks, as this field was copied
1579 * with memcpy).
1580 *
1581 * This _changes_ the previous behaviour, where
1582 * tcp_create_openreq_child always was incrementing the
1583 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1584 * to be taken into account in all callers. -acme
1585 */
1586 sk_refcnt_debug_inc(newsk);
1587 sk_set_socket(newsk, NULL);
1588 newsk->sk_wq = NULL;
1589
1590 if (newsk->sk_prot->sockets_allocated)
1591 sk_sockets_allocated_inc(newsk);
1592
1593 if (sock_needs_netstamp(sk) &&
1594 newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1595 net_enable_timestamp();
1596 }
1597 out:
1598 return newsk;
1599 }
1600 EXPORT_SYMBOL_GPL(sk_clone_lock);
1601
1602 void sk_free_unlock_clone(struct sock *sk)
1603 {
1604 /* It is still raw copy of parent, so invalidate
1605 * destructor and make plain sk_free() */
1606 sk->sk_destruct = NULL;
1607 bh_unlock_sock(sk);
1608 sk_free(sk);
1609 }
1610 EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
1611
1612 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
1613 {
1614 u32 max_segs = 1;
1615
1616 sk_dst_set(sk, dst);
1617 sk->sk_route_caps = dst->dev->features;
1618 if (sk->sk_route_caps & NETIF_F_GSO)
1619 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
1620 sk->sk_route_caps &= ~sk->sk_route_nocaps;
1621 if (sk_can_gso(sk)) {
1622 if (dst->header_len) {
1623 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
1624 } else {
1625 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
1626 sk->sk_gso_max_size = dst->dev->gso_max_size;
1627 max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
1628 }
1629 }
1630 sk->sk_gso_max_segs = max_segs;
1631 }
1632 EXPORT_SYMBOL_GPL(sk_setup_caps);
1633
1634 /*
1635 * Simple resource managers for sockets.
1636 */
1637
1638
1639 /*
1640 * Write buffer destructor automatically called from kfree_skb.
1641 */
1642 void sock_wfree(struct sk_buff *skb)
1643 {
1644 struct sock *sk = skb->sk;
1645 unsigned int len = skb->truesize;
1646
1647 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
1648 /*
1649 * Keep a reference on sk_wmem_alloc, this will be released
1650 * after sk_write_space() call
1651 */
1652 atomic_sub(len - 1, &sk->sk_wmem_alloc);
1653 sk->sk_write_space(sk);
1654 len = 1;
1655 }
1656 /*
1657 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
1658 * could not do because of in-flight packets
1659 */
1660 if (atomic_sub_and_test(len, &sk->sk_wmem_alloc))
1661 __sk_free(sk);
1662 }
1663 EXPORT_SYMBOL(sock_wfree);
1664
1665 /* This variant of sock_wfree() is used by TCP,
1666 * since it sets SOCK_USE_WRITE_QUEUE.
1667 */
1668 void __sock_wfree(struct sk_buff *skb)
1669 {
1670 struct sock *sk = skb->sk;
1671
1672 if (atomic_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
1673 __sk_free(sk);
1674 }
1675
1676 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
1677 {
1678 skb_orphan(skb);
1679 skb->sk = sk;
1680 #ifdef CONFIG_INET
1681 if (unlikely(!sk_fullsock(sk))) {
1682 skb->destructor = sock_edemux;
1683 sock_hold(sk);
1684 return;
1685 }
1686 #endif
1687 skb->destructor = sock_wfree;
1688 skb_set_hash_from_sk(skb, sk);
1689 /*
1690 * We used to take a refcount on sk, but following operation
1691 * is enough to guarantee sk_free() wont free this sock until
1692 * all in-flight packets are completed
1693 */
1694 atomic_add(skb->truesize, &sk->sk_wmem_alloc);
1695 }
1696 EXPORT_SYMBOL(skb_set_owner_w);
1697
1698 /* This helper is used by netem, as it can hold packets in its
1699 * delay queue. We want to allow the owner socket to send more
1700 * packets, as if they were already TX completed by a typical driver.
1701 * But we also want to keep skb->sk set because some packet schedulers
1702 * rely on it (sch_fq for example). So we set skb->truesize to a small
1703 * amount (1) and decrease sk_wmem_alloc accordingly.
1704 */
1705 void skb_orphan_partial(struct sk_buff *skb)
1706 {
1707 /* If this skb is a TCP pure ACK or already went here,
1708 * we have nothing to do. 2 is already a very small truesize.
1709 */
1710 if (skb->truesize <= 2)
1711 return;
1712
1713 /* TCP stack sets skb->ooo_okay based on sk_wmem_alloc,
1714 * so we do not completely orphan skb, but transfert all
1715 * accounted bytes but one, to avoid unexpected reorders.
1716 */
1717 if (skb->destructor == sock_wfree
1718 #ifdef CONFIG_INET
1719 || skb->destructor == tcp_wfree
1720 #endif
1721 ) {
1722 atomic_sub(skb->truesize - 1, &skb->sk->sk_wmem_alloc);
1723 skb->truesize = 1;
1724 } else {
1725 skb_orphan(skb);
1726 }
1727 }
1728 EXPORT_SYMBOL(skb_orphan_partial);
1729
1730 /*
1731 * Read buffer destructor automatically called from kfree_skb.
1732 */
1733 void sock_rfree(struct sk_buff *skb)
1734 {
1735 struct sock *sk = skb->sk;
1736 unsigned int len = skb->truesize;
1737
1738 atomic_sub(len, &sk->sk_rmem_alloc);
1739 sk_mem_uncharge(sk, len);
1740 }
1741 EXPORT_SYMBOL(sock_rfree);
1742
1743 /*
1744 * Buffer destructor for skbs that are not used directly in read or write
1745 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
1746 */
1747 void sock_efree(struct sk_buff *skb)
1748 {
1749 sock_put(skb->sk);
1750 }
1751 EXPORT_SYMBOL(sock_efree);
1752
1753 kuid_t sock_i_uid(struct sock *sk)
1754 {
1755 kuid_t uid;
1756
1757 read_lock_bh(&sk->sk_callback_lock);
1758 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
1759 read_unlock_bh(&sk->sk_callback_lock);
1760 return uid;
1761 }
1762 EXPORT_SYMBOL(sock_i_uid);
1763
1764 unsigned long sock_i_ino(struct sock *sk)
1765 {
1766 unsigned long ino;
1767
1768 read_lock_bh(&sk->sk_callback_lock);
1769 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
1770 read_unlock_bh(&sk->sk_callback_lock);
1771 return ino;
1772 }
1773 EXPORT_SYMBOL(sock_i_ino);
1774
1775 /*
1776 * Allocate a skb from the socket's send buffer.
1777 */
1778 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
1779 gfp_t priority)
1780 {
1781 if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) {
1782 struct sk_buff *skb = alloc_skb(size, priority);
1783 if (skb) {
1784 skb_set_owner_w(skb, sk);
1785 return skb;
1786 }
1787 }
1788 return NULL;
1789 }
1790 EXPORT_SYMBOL(sock_wmalloc);
1791
1792 /*
1793 * Allocate a memory block from the socket's option memory buffer.
1794 */
1795 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
1796 {
1797 if ((unsigned int)size <= sysctl_optmem_max &&
1798 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
1799 void *mem;
1800 /* First do the add, to avoid the race if kmalloc
1801 * might sleep.
1802 */
1803 atomic_add(size, &sk->sk_omem_alloc);
1804 mem = kmalloc(size, priority);
1805 if (mem)
1806 return mem;
1807 atomic_sub(size, &sk->sk_omem_alloc);
1808 }
1809 return NULL;
1810 }
1811 EXPORT_SYMBOL(sock_kmalloc);
1812
1813 /* Free an option memory block. Note, we actually want the inline
1814 * here as this allows gcc to detect the nullify and fold away the
1815 * condition entirely.
1816 */
1817 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
1818 const bool nullify)
1819 {
1820 if (WARN_ON_ONCE(!mem))
1821 return;
1822 if (nullify)
1823 kzfree(mem);
1824 else
1825 kfree(mem);
1826 atomic_sub(size, &sk->sk_omem_alloc);
1827 }
1828
1829 void sock_kfree_s(struct sock *sk, void *mem, int size)
1830 {
1831 __sock_kfree_s(sk, mem, size, false);
1832 }
1833 EXPORT_SYMBOL(sock_kfree_s);
1834
1835 void sock_kzfree_s(struct sock *sk, void *mem, int size)
1836 {
1837 __sock_kfree_s(sk, mem, size, true);
1838 }
1839 EXPORT_SYMBOL(sock_kzfree_s);
1840
1841 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
1842 I think, these locks should be removed for datagram sockets.
1843 */
1844 static long sock_wait_for_wmem(struct sock *sk, long timeo)
1845 {
1846 DEFINE_WAIT(wait);
1847
1848 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1849 for (;;) {
1850 if (!timeo)
1851 break;
1852 if (signal_pending(current))
1853 break;
1854 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1855 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
1856 if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf)
1857 break;
1858 if (sk->sk_shutdown & SEND_SHUTDOWN)
1859 break;
1860 if (sk->sk_err)
1861 break;
1862 timeo = schedule_timeout(timeo);
1863 }
1864 finish_wait(sk_sleep(sk), &wait);
1865 return timeo;
1866 }
1867
1868
1869 /*
1870 * Generic send/receive buffer handlers
1871 */
1872
1873 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
1874 unsigned long data_len, int noblock,
1875 int *errcode, int max_page_order)
1876 {
1877 struct sk_buff *skb;
1878 long timeo;
1879 int err;
1880
1881 timeo = sock_sndtimeo(sk, noblock);
1882 for (;;) {
1883 err = sock_error(sk);
1884 if (err != 0)
1885 goto failure;
1886
1887 err = -EPIPE;
1888 if (sk->sk_shutdown & SEND_SHUTDOWN)
1889 goto failure;
1890
1891 if (sk_wmem_alloc_get(sk) < sk->sk_sndbuf)
1892 break;
1893
1894 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1895 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1896 err = -EAGAIN;
1897 if (!timeo)
1898 goto failure;
1899 if (signal_pending(current))
1900 goto interrupted;
1901 timeo = sock_wait_for_wmem(sk, timeo);
1902 }
1903 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
1904 errcode, sk->sk_allocation);
1905 if (skb)
1906 skb_set_owner_w(skb, sk);
1907 return skb;
1908
1909 interrupted:
1910 err = sock_intr_errno(timeo);
1911 failure:
1912 *errcode = err;
1913 return NULL;
1914 }
1915 EXPORT_SYMBOL(sock_alloc_send_pskb);
1916
1917 struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
1918 int noblock, int *errcode)
1919 {
1920 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
1921 }
1922 EXPORT_SYMBOL(sock_alloc_send_skb);
1923
1924 int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
1925 struct sockcm_cookie *sockc)
1926 {
1927 u32 tsflags;
1928
1929 switch (cmsg->cmsg_type) {
1930 case SO_MARK:
1931 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
1932 return -EPERM;
1933 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
1934 return -EINVAL;
1935 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
1936 break;
1937 case SO_TIMESTAMPING:
1938 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
1939 return -EINVAL;
1940
1941 tsflags = *(u32 *)CMSG_DATA(cmsg);
1942 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
1943 return -EINVAL;
1944
1945 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
1946 sockc->tsflags |= tsflags;
1947 break;
1948 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
1949 case SCM_RIGHTS:
1950 case SCM_CREDENTIALS:
1951 break;
1952 default:
1953 return -EINVAL;
1954 }
1955 return 0;
1956 }
1957 EXPORT_SYMBOL(__sock_cmsg_send);
1958
1959 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
1960 struct sockcm_cookie *sockc)
1961 {
1962 struct cmsghdr *cmsg;
1963 int ret;
1964
1965 for_each_cmsghdr(cmsg, msg) {
1966 if (!CMSG_OK(msg, cmsg))
1967 return -EINVAL;
1968 if (cmsg->cmsg_level != SOL_SOCKET)
1969 continue;
1970 ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
1971 if (ret)
1972 return ret;
1973 }
1974 return 0;
1975 }
1976 EXPORT_SYMBOL(sock_cmsg_send);
1977
1978 /* On 32bit arches, an skb frag is limited to 2^15 */
1979 #define SKB_FRAG_PAGE_ORDER get_order(32768)
1980
1981 /**
1982 * skb_page_frag_refill - check that a page_frag contains enough room
1983 * @sz: minimum size of the fragment we want to get
1984 * @pfrag: pointer to page_frag
1985 * @gfp: priority for memory allocation
1986 *
1987 * Note: While this allocator tries to use high order pages, there is
1988 * no guarantee that allocations succeed. Therefore, @sz MUST be
1989 * less or equal than PAGE_SIZE.
1990 */
1991 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
1992 {
1993 if (pfrag->page) {
1994 if (page_ref_count(pfrag->page) == 1) {
1995 pfrag->offset = 0;
1996 return true;
1997 }
1998 if (pfrag->offset + sz <= pfrag->size)
1999 return true;
2000 put_page(pfrag->page);
2001 }
2002
2003 pfrag->offset = 0;
2004 if (SKB_FRAG_PAGE_ORDER) {
2005 /* Avoid direct reclaim but allow kswapd to wake */
2006 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2007 __GFP_COMP | __GFP_NOWARN |
2008 __GFP_NORETRY,
2009 SKB_FRAG_PAGE_ORDER);
2010 if (likely(pfrag->page)) {
2011 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2012 return true;
2013 }
2014 }
2015 pfrag->page = alloc_page(gfp);
2016 if (likely(pfrag->page)) {
2017 pfrag->size = PAGE_SIZE;
2018 return true;
2019 }
2020 return false;
2021 }
2022 EXPORT_SYMBOL(skb_page_frag_refill);
2023
2024 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2025 {
2026 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2027 return true;
2028
2029 sk_enter_memory_pressure(sk);
2030 sk_stream_moderate_sndbuf(sk);
2031 return false;
2032 }
2033 EXPORT_SYMBOL(sk_page_frag_refill);
2034
2035 static void __lock_sock(struct sock *sk)
2036 __releases(&sk->sk_lock.slock)
2037 __acquires(&sk->sk_lock.slock)
2038 {
2039 DEFINE_WAIT(wait);
2040
2041 for (;;) {
2042 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2043 TASK_UNINTERRUPTIBLE);
2044 spin_unlock_bh(&sk->sk_lock.slock);
2045 schedule();
2046 spin_lock_bh(&sk->sk_lock.slock);
2047 if (!sock_owned_by_user(sk))
2048 break;
2049 }
2050 finish_wait(&sk->sk_lock.wq, &wait);
2051 }
2052
2053 static void __release_sock(struct sock *sk)
2054 __releases(&sk->sk_lock.slock)
2055 __acquires(&sk->sk_lock.slock)
2056 {
2057 struct sk_buff *skb, *next;
2058
2059 while ((skb = sk->sk_backlog.head) != NULL) {
2060 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2061
2062 spin_unlock_bh(&sk->sk_lock.slock);
2063
2064 do {
2065 next = skb->next;
2066 prefetch(next);
2067 WARN_ON_ONCE(skb_dst_is_noref(skb));
2068 skb->next = NULL;
2069 sk_backlog_rcv(sk, skb);
2070
2071 cond_resched();
2072
2073 skb = next;
2074 } while (skb != NULL);
2075
2076 spin_lock_bh(&sk->sk_lock.slock);
2077 }
2078
2079 /*
2080 * Doing the zeroing here guarantee we can not loop forever
2081 * while a wild producer attempts to flood us.
2082 */
2083 sk->sk_backlog.len = 0;
2084 }
2085
2086 void __sk_flush_backlog(struct sock *sk)
2087 {
2088 spin_lock_bh(&sk->sk_lock.slock);
2089 __release_sock(sk);
2090 spin_unlock_bh(&sk->sk_lock.slock);
2091 }
2092
2093 /**
2094 * sk_wait_data - wait for data to arrive at sk_receive_queue
2095 * @sk: sock to wait on
2096 * @timeo: for how long
2097 * @skb: last skb seen on sk_receive_queue
2098 *
2099 * Now socket state including sk->sk_err is changed only under lock,
2100 * hence we may omit checks after joining wait queue.
2101 * We check receive queue before schedule() only as optimization;
2102 * it is very likely that release_sock() added new data.
2103 */
2104 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2105 {
2106 DEFINE_WAIT_FUNC(wait, woken_wake_function);
2107 int rc;
2108
2109 add_wait_queue(sk_sleep(sk), &wait);
2110 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2111 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2112 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2113 remove_wait_queue(sk_sleep(sk), &wait);
2114 return rc;
2115 }
2116 EXPORT_SYMBOL(sk_wait_data);
2117
2118 /**
2119 * __sk_mem_raise_allocated - increase memory_allocated
2120 * @sk: socket
2121 * @size: memory size to allocate
2122 * @amt: pages to allocate
2123 * @kind: allocation type
2124 *
2125 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2126 */
2127 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2128 {
2129 struct proto *prot = sk->sk_prot;
2130 long allocated = sk_memory_allocated_add(sk, amt);
2131
2132 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2133 !mem_cgroup_charge_skmem(sk->sk_memcg, amt))
2134 goto suppress_allocation;
2135
2136 /* Under limit. */
2137 if (allocated <= sk_prot_mem_limits(sk, 0)) {
2138 sk_leave_memory_pressure(sk);
2139 return 1;
2140 }
2141
2142 /* Under pressure. */
2143 if (allocated > sk_prot_mem_limits(sk, 1))
2144 sk_enter_memory_pressure(sk);
2145
2146 /* Over hard limit. */
2147 if (allocated > sk_prot_mem_limits(sk, 2))
2148 goto suppress_allocation;
2149
2150 /* guarantee minimum buffer size under pressure */
2151 if (kind == SK_MEM_RECV) {
2152 if (atomic_read(&sk->sk_rmem_alloc) < prot->sysctl_rmem[0])
2153 return 1;
2154
2155 } else { /* SK_MEM_SEND */
2156 if (sk->sk_type == SOCK_STREAM) {
2157 if (sk->sk_wmem_queued < prot->sysctl_wmem[0])
2158 return 1;
2159 } else if (atomic_read(&sk->sk_wmem_alloc) <
2160 prot->sysctl_wmem[0])
2161 return 1;
2162 }
2163
2164 if (sk_has_memory_pressure(sk)) {
2165 int alloc;
2166
2167 if (!sk_under_memory_pressure(sk))
2168 return 1;
2169 alloc = sk_sockets_allocated_read_positive(sk);
2170 if (sk_prot_mem_limits(sk, 2) > alloc *
2171 sk_mem_pages(sk->sk_wmem_queued +
2172 atomic_read(&sk->sk_rmem_alloc) +
2173 sk->sk_forward_alloc))
2174 return 1;
2175 }
2176
2177 suppress_allocation:
2178
2179 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2180 sk_stream_moderate_sndbuf(sk);
2181
2182 /* Fail only if socket is _under_ its sndbuf.
2183 * In this case we cannot block, so that we have to fail.
2184 */
2185 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2186 return 1;
2187 }
2188
2189 trace_sock_exceed_buf_limit(sk, prot, allocated);
2190
2191 sk_memory_allocated_sub(sk, amt);
2192
2193 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2194 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2195
2196 return 0;
2197 }
2198 EXPORT_SYMBOL(__sk_mem_raise_allocated);
2199
2200 /**
2201 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2202 * @sk: socket
2203 * @size: memory size to allocate
2204 * @kind: allocation type
2205 *
2206 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2207 * rmem allocation. This function assumes that protocols which have
2208 * memory_pressure use sk_wmem_queued as write buffer accounting.
2209 */
2210 int __sk_mem_schedule(struct sock *sk, int size, int kind)
2211 {
2212 int ret, amt = sk_mem_pages(size);
2213
2214 sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2215 ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2216 if (!ret)
2217 sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2218 return ret;
2219 }
2220 EXPORT_SYMBOL(__sk_mem_schedule);
2221
2222 /**
2223 * __sk_mem_reduce_allocated - reclaim memory_allocated
2224 * @sk: socket
2225 * @amount: number of quanta
2226 *
2227 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2228 */
2229 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2230 {
2231 sk_memory_allocated_sub(sk, amount);
2232
2233 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2234 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2235
2236 if (sk_under_memory_pressure(sk) &&
2237 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2238 sk_leave_memory_pressure(sk);
2239 }
2240 EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2241
2242 /**
2243 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2244 * @sk: socket
2245 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2246 */
2247 void __sk_mem_reclaim(struct sock *sk, int amount)
2248 {
2249 amount >>= SK_MEM_QUANTUM_SHIFT;
2250 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2251 __sk_mem_reduce_allocated(sk, amount);
2252 }
2253 EXPORT_SYMBOL(__sk_mem_reclaim);
2254
2255 int sk_set_peek_off(struct sock *sk, int val)
2256 {
2257 if (val < 0)
2258 return -EINVAL;
2259
2260 sk->sk_peek_off = val;
2261 return 0;
2262 }
2263 EXPORT_SYMBOL_GPL(sk_set_peek_off);
2264
2265 /*
2266 * Set of default routines for initialising struct proto_ops when
2267 * the protocol does not support a particular function. In certain
2268 * cases where it makes no sense for a protocol to have a "do nothing"
2269 * function, some default processing is provided.
2270 */
2271
2272 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2273 {
2274 return -EOPNOTSUPP;
2275 }
2276 EXPORT_SYMBOL(sock_no_bind);
2277
2278 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2279 int len, int flags)
2280 {
2281 return -EOPNOTSUPP;
2282 }
2283 EXPORT_SYMBOL(sock_no_connect);
2284
2285 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2286 {
2287 return -EOPNOTSUPP;
2288 }
2289 EXPORT_SYMBOL(sock_no_socketpair);
2290
2291 int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2292 bool kern)
2293 {
2294 return -EOPNOTSUPP;
2295 }
2296 EXPORT_SYMBOL(sock_no_accept);
2297
2298 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2299 int *len, int peer)
2300 {
2301 return -EOPNOTSUPP;
2302 }
2303 EXPORT_SYMBOL(sock_no_getname);
2304
2305 unsigned int sock_no_poll(struct file *file, struct socket *sock, poll_table *pt)
2306 {
2307 return 0;
2308 }
2309 EXPORT_SYMBOL(sock_no_poll);
2310
2311 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2312 {
2313 return -EOPNOTSUPP;
2314 }
2315 EXPORT_SYMBOL(sock_no_ioctl);
2316
2317 int sock_no_listen(struct socket *sock, int backlog)
2318 {
2319 return -EOPNOTSUPP;
2320 }
2321 EXPORT_SYMBOL(sock_no_listen);
2322
2323 int sock_no_shutdown(struct socket *sock, int how)
2324 {
2325 return -EOPNOTSUPP;
2326 }
2327 EXPORT_SYMBOL(sock_no_shutdown);
2328
2329 int sock_no_setsockopt(struct socket *sock, int level, int optname,
2330 char __user *optval, unsigned int optlen)
2331 {
2332 return -EOPNOTSUPP;
2333 }
2334 EXPORT_SYMBOL(sock_no_setsockopt);
2335
2336 int sock_no_getsockopt(struct socket *sock, int level, int optname,
2337 char __user *optval, int __user *optlen)
2338 {
2339 return -EOPNOTSUPP;
2340 }
2341 EXPORT_SYMBOL(sock_no_getsockopt);
2342
2343 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2344 {
2345 return -EOPNOTSUPP;
2346 }
2347 EXPORT_SYMBOL(sock_no_sendmsg);
2348
2349 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2350 int flags)
2351 {
2352 return -EOPNOTSUPP;
2353 }
2354 EXPORT_SYMBOL(sock_no_recvmsg);
2355
2356 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2357 {
2358 /* Mirror missing mmap method error code */
2359 return -ENODEV;
2360 }
2361 EXPORT_SYMBOL(sock_no_mmap);
2362
2363 ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2364 {
2365 ssize_t res;
2366 struct msghdr msg = {.msg_flags = flags};
2367 struct kvec iov;
2368 char *kaddr = kmap(page);
2369 iov.iov_base = kaddr + offset;
2370 iov.iov_len = size;
2371 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2372 kunmap(page);
2373 return res;
2374 }
2375 EXPORT_SYMBOL(sock_no_sendpage);
2376
2377 /*
2378 * Default Socket Callbacks
2379 */
2380
2381 static void sock_def_wakeup(struct sock *sk)
2382 {
2383 struct socket_wq *wq;
2384
2385 rcu_read_lock();
2386 wq = rcu_dereference(sk->sk_wq);
2387 if (skwq_has_sleeper(wq))
2388 wake_up_interruptible_all(&wq->wait);
2389 rcu_read_unlock();
2390 }
2391
2392 static void sock_def_error_report(struct sock *sk)
2393 {
2394 struct socket_wq *wq;
2395
2396 rcu_read_lock();
2397 wq = rcu_dereference(sk->sk_wq);
2398 if (skwq_has_sleeper(wq))
2399 wake_up_interruptible_poll(&wq->wait, POLLERR);
2400 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2401 rcu_read_unlock();
2402 }
2403
2404 static void sock_def_readable(struct sock *sk)
2405 {
2406 struct socket_wq *wq;
2407
2408 rcu_read_lock();
2409 wq = rcu_dereference(sk->sk_wq);
2410 if (skwq_has_sleeper(wq))
2411 wake_up_interruptible_sync_poll(&wq->wait, POLLIN | POLLPRI |
2412 POLLRDNORM | POLLRDBAND);
2413 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2414 rcu_read_unlock();
2415 }
2416
2417 static void sock_def_write_space(struct sock *sk)
2418 {
2419 struct socket_wq *wq;
2420
2421 rcu_read_lock();
2422
2423 /* Do not wake up a writer until he can make "significant"
2424 * progress. --DaveM
2425 */
2426 if ((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) {
2427 wq = rcu_dereference(sk->sk_wq);
2428 if (skwq_has_sleeper(wq))
2429 wake_up_interruptible_sync_poll(&wq->wait, POLLOUT |
2430 POLLWRNORM | POLLWRBAND);
2431
2432 /* Should agree with poll, otherwise some programs break */
2433 if (sock_writeable(sk))
2434 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2435 }
2436
2437 rcu_read_unlock();
2438 }
2439
2440 static void sock_def_destruct(struct sock *sk)
2441 {
2442 }
2443
2444 void sk_send_sigurg(struct sock *sk)
2445 {
2446 if (sk->sk_socket && sk->sk_socket->file)
2447 if (send_sigurg(&sk->sk_socket->file->f_owner))
2448 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2449 }
2450 EXPORT_SYMBOL(sk_send_sigurg);
2451
2452 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2453 unsigned long expires)
2454 {
2455 if (!mod_timer(timer, expires))
2456 sock_hold(sk);
2457 }
2458 EXPORT_SYMBOL(sk_reset_timer);
2459
2460 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2461 {
2462 if (del_timer(timer))
2463 __sock_put(sk);
2464 }
2465 EXPORT_SYMBOL(sk_stop_timer);
2466
2467 void sock_init_data(struct socket *sock, struct sock *sk)
2468 {
2469 skb_queue_head_init(&sk->sk_receive_queue);
2470 skb_queue_head_init(&sk->sk_write_queue);
2471 skb_queue_head_init(&sk->sk_error_queue);
2472
2473 sk->sk_send_head = NULL;
2474
2475 init_timer(&sk->sk_timer);
2476
2477 sk->sk_allocation = GFP_KERNEL;
2478 sk->sk_rcvbuf = sysctl_rmem_default;
2479 sk->sk_sndbuf = sysctl_wmem_default;
2480 sk->sk_state = TCP_CLOSE;
2481 sk_set_socket(sk, sock);
2482
2483 sock_set_flag(sk, SOCK_ZAPPED);
2484
2485 if (sock) {
2486 sk->sk_type = sock->type;
2487 sk->sk_wq = sock->wq;
2488 sock->sk = sk;
2489 sk->sk_uid = SOCK_INODE(sock)->i_uid;
2490 } else {
2491 sk->sk_wq = NULL;
2492 sk->sk_uid = make_kuid(sock_net(sk)->user_ns, 0);
2493 }
2494
2495 rwlock_init(&sk->sk_callback_lock);
2496 if (sk->sk_kern_sock)
2497 lockdep_set_class_and_name(
2498 &sk->sk_callback_lock,
2499 af_kern_callback_keys + sk->sk_family,
2500 af_family_kern_clock_key_strings[sk->sk_family]);
2501 else
2502 lockdep_set_class_and_name(
2503 &sk->sk_callback_lock,
2504 af_callback_keys + sk->sk_family,
2505 af_family_clock_key_strings[sk->sk_family]);
2506
2507 sk->sk_state_change = sock_def_wakeup;
2508 sk->sk_data_ready = sock_def_readable;
2509 sk->sk_write_space = sock_def_write_space;
2510 sk->sk_error_report = sock_def_error_report;
2511 sk->sk_destruct = sock_def_destruct;
2512
2513 sk->sk_frag.page = NULL;
2514 sk->sk_frag.offset = 0;
2515 sk->sk_peek_off = -1;
2516
2517 sk->sk_peer_pid = NULL;
2518 sk->sk_peer_cred = NULL;
2519 sk->sk_write_pending = 0;
2520 sk->sk_rcvlowat = 1;
2521 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
2522 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
2523
2524 sk->sk_stamp = ktime_set(-1L, 0);
2525
2526 #ifdef CONFIG_NET_RX_BUSY_POLL
2527 sk->sk_napi_id = 0;
2528 sk->sk_ll_usec = sysctl_net_busy_read;
2529 #endif
2530
2531 sk->sk_max_pacing_rate = ~0U;
2532 sk->sk_pacing_rate = ~0U;
2533 sk->sk_incoming_cpu = -1;
2534 /*
2535 * Before updating sk_refcnt, we must commit prior changes to memory
2536 * (Documentation/RCU/rculist_nulls.txt for details)
2537 */
2538 smp_wmb();
2539 atomic_set(&sk->sk_refcnt, 1);
2540 atomic_set(&sk->sk_drops, 0);
2541 }
2542 EXPORT_SYMBOL(sock_init_data);
2543
2544 void lock_sock_nested(struct sock *sk, int subclass)
2545 {
2546 might_sleep();
2547 spin_lock_bh(&sk->sk_lock.slock);
2548 if (sk->sk_lock.owned)
2549 __lock_sock(sk);
2550 sk->sk_lock.owned = 1;
2551 spin_unlock(&sk->sk_lock.slock);
2552 /*
2553 * The sk_lock has mutex_lock() semantics here:
2554 */
2555 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
2556 local_bh_enable();
2557 }
2558 EXPORT_SYMBOL(lock_sock_nested);
2559
2560 void release_sock(struct sock *sk)
2561 {
2562 spin_lock_bh(&sk->sk_lock.slock);
2563 if (sk->sk_backlog.tail)
2564 __release_sock(sk);
2565
2566 /* Warning : release_cb() might need to release sk ownership,
2567 * ie call sock_release_ownership(sk) before us.
2568 */
2569 if (sk->sk_prot->release_cb)
2570 sk->sk_prot->release_cb(sk);
2571
2572 sock_release_ownership(sk);
2573 if (waitqueue_active(&sk->sk_lock.wq))
2574 wake_up(&sk->sk_lock.wq);
2575 spin_unlock_bh(&sk->sk_lock.slock);
2576 }
2577 EXPORT_SYMBOL(release_sock);
2578
2579 /**
2580 * lock_sock_fast - fast version of lock_sock
2581 * @sk: socket
2582 *
2583 * This version should be used for very small section, where process wont block
2584 * return false if fast path is taken
2585 * sk_lock.slock locked, owned = 0, BH disabled
2586 * return true if slow path is taken
2587 * sk_lock.slock unlocked, owned = 1, BH enabled
2588 */
2589 bool lock_sock_fast(struct sock *sk)
2590 {
2591 might_sleep();
2592 spin_lock_bh(&sk->sk_lock.slock);
2593
2594 if (!sk->sk_lock.owned)
2595 /*
2596 * Note : We must disable BH
2597 */
2598 return false;
2599
2600 __lock_sock(sk);
2601 sk->sk_lock.owned = 1;
2602 spin_unlock(&sk->sk_lock.slock);
2603 /*
2604 * The sk_lock has mutex_lock() semantics here:
2605 */
2606 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
2607 local_bh_enable();
2608 return true;
2609 }
2610 EXPORT_SYMBOL(lock_sock_fast);
2611
2612 int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp)
2613 {
2614 struct timeval tv;
2615 if (!sock_flag(sk, SOCK_TIMESTAMP))
2616 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2617 tv = ktime_to_timeval(sk->sk_stamp);
2618 if (tv.tv_sec == -1)
2619 return -ENOENT;
2620 if (tv.tv_sec == 0) {
2621 sk->sk_stamp = ktime_get_real();
2622 tv = ktime_to_timeval(sk->sk_stamp);
2623 }
2624 return copy_to_user(userstamp, &tv, sizeof(tv)) ? -EFAULT : 0;
2625 }
2626 EXPORT_SYMBOL(sock_get_timestamp);
2627
2628 int sock_get_timestampns(struct sock *sk, struct timespec __user *userstamp)
2629 {
2630 struct timespec ts;
2631 if (!sock_flag(sk, SOCK_TIMESTAMP))
2632 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
2633 ts = ktime_to_timespec(sk->sk_stamp);
2634 if (ts.tv_sec == -1)
2635 return -ENOENT;
2636 if (ts.tv_sec == 0) {
2637 sk->sk_stamp = ktime_get_real();
2638 ts = ktime_to_timespec(sk->sk_stamp);
2639 }
2640 return copy_to_user(userstamp, &ts, sizeof(ts)) ? -EFAULT : 0;
2641 }
2642 EXPORT_SYMBOL(sock_get_timestampns);
2643
2644 void sock_enable_timestamp(struct sock *sk, int flag)
2645 {
2646 if (!sock_flag(sk, flag)) {
2647 unsigned long previous_flags = sk->sk_flags;
2648
2649 sock_set_flag(sk, flag);
2650 /*
2651 * we just set one of the two flags which require net
2652 * time stamping, but time stamping might have been on
2653 * already because of the other one
2654 */
2655 if (sock_needs_netstamp(sk) &&
2656 !(previous_flags & SK_FLAGS_TIMESTAMP))
2657 net_enable_timestamp();
2658 }
2659 }
2660
2661 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
2662 int level, int type)
2663 {
2664 struct sock_exterr_skb *serr;
2665 struct sk_buff *skb;
2666 int copied, err;
2667
2668 err = -EAGAIN;
2669 skb = sock_dequeue_err_skb(sk);
2670 if (skb == NULL)
2671 goto out;
2672
2673 copied = skb->len;
2674 if (copied > len) {
2675 msg->msg_flags |= MSG_TRUNC;
2676 copied = len;
2677 }
2678 err = skb_copy_datagram_msg(skb, 0, msg, copied);
2679 if (err)
2680 goto out_free_skb;
2681
2682 sock_recv_timestamp(msg, sk, skb);
2683
2684 serr = SKB_EXT_ERR(skb);
2685 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
2686
2687 msg->msg_flags |= MSG_ERRQUEUE;
2688 err = copied;
2689
2690 out_free_skb:
2691 kfree_skb(skb);
2692 out:
2693 return err;
2694 }
2695 EXPORT_SYMBOL(sock_recv_errqueue);
2696
2697 /*
2698 * Get a socket option on an socket.
2699 *
2700 * FIX: POSIX 1003.1g is very ambiguous here. It states that
2701 * asynchronous errors should be reported by getsockopt. We assume
2702 * this means if you specify SO_ERROR (otherwise whats the point of it).
2703 */
2704 int sock_common_getsockopt(struct socket *sock, int level, int optname,
2705 char __user *optval, int __user *optlen)
2706 {
2707 struct sock *sk = sock->sk;
2708
2709 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2710 }
2711 EXPORT_SYMBOL(sock_common_getsockopt);
2712
2713 #ifdef CONFIG_COMPAT
2714 int compat_sock_common_getsockopt(struct socket *sock, int level, int optname,
2715 char __user *optval, int __user *optlen)
2716 {
2717 struct sock *sk = sock->sk;
2718
2719 if (sk->sk_prot->compat_getsockopt != NULL)
2720 return sk->sk_prot->compat_getsockopt(sk, level, optname,
2721 optval, optlen);
2722 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
2723 }
2724 EXPORT_SYMBOL(compat_sock_common_getsockopt);
2725 #endif
2726
2727 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
2728 int flags)
2729 {
2730 struct sock *sk = sock->sk;
2731 int addr_len = 0;
2732 int err;
2733
2734 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
2735 flags & ~MSG_DONTWAIT, &addr_len);
2736 if (err >= 0)
2737 msg->msg_namelen = addr_len;
2738 return err;
2739 }
2740 EXPORT_SYMBOL(sock_common_recvmsg);
2741
2742 /*
2743 * Set socket options on an inet socket.
2744 */
2745 int sock_common_setsockopt(struct socket *sock, int level, int optname,
2746 char __user *optval, unsigned int optlen)
2747 {
2748 struct sock *sk = sock->sk;
2749
2750 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2751 }
2752 EXPORT_SYMBOL(sock_common_setsockopt);
2753
2754 #ifdef CONFIG_COMPAT
2755 int compat_sock_common_setsockopt(struct socket *sock, int level, int optname,
2756 char __user *optval, unsigned int optlen)
2757 {
2758 struct sock *sk = sock->sk;
2759
2760 if (sk->sk_prot->compat_setsockopt != NULL)
2761 return sk->sk_prot->compat_setsockopt(sk, level, optname,
2762 optval, optlen);
2763 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
2764 }
2765 EXPORT_SYMBOL(compat_sock_common_setsockopt);
2766 #endif
2767
2768 void sk_common_release(struct sock *sk)
2769 {
2770 if (sk->sk_prot->destroy)
2771 sk->sk_prot->destroy(sk);
2772
2773 /*
2774 * Observation: when sock_common_release is called, processes have
2775 * no access to socket. But net still has.
2776 * Step one, detach it from networking:
2777 *
2778 * A. Remove from hash tables.
2779 */
2780
2781 sk->sk_prot->unhash(sk);
2782
2783 /*
2784 * In this point socket cannot receive new packets, but it is possible
2785 * that some packets are in flight because some CPU runs receiver and
2786 * did hash table lookup before we unhashed socket. They will achieve
2787 * receive queue and will be purged by socket destructor.
2788 *
2789 * Also we still have packets pending on receive queue and probably,
2790 * our own packets waiting in device queues. sock_destroy will drain
2791 * receive queue, but transmitted packets will delay socket destruction
2792 * until the last reference will be released.
2793 */
2794
2795 sock_orphan(sk);
2796
2797 xfrm_sk_free_policy(sk);
2798
2799 sk_refcnt_debug_release(sk);
2800
2801 sock_put(sk);
2802 }
2803 EXPORT_SYMBOL(sk_common_release);
2804
2805 #ifdef CONFIG_PROC_FS
2806 #define PROTO_INUSE_NR 64 /* should be enough for the first time */
2807 struct prot_inuse {
2808 int val[PROTO_INUSE_NR];
2809 };
2810
2811 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
2812
2813 #ifdef CONFIG_NET_NS
2814 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2815 {
2816 __this_cpu_add(net->core.inuse->val[prot->inuse_idx], val);
2817 }
2818 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2819
2820 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2821 {
2822 int cpu, idx = prot->inuse_idx;
2823 int res = 0;
2824
2825 for_each_possible_cpu(cpu)
2826 res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
2827
2828 return res >= 0 ? res : 0;
2829 }
2830 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2831
2832 static int __net_init sock_inuse_init_net(struct net *net)
2833 {
2834 net->core.inuse = alloc_percpu(struct prot_inuse);
2835 return net->core.inuse ? 0 : -ENOMEM;
2836 }
2837
2838 static void __net_exit sock_inuse_exit_net(struct net *net)
2839 {
2840 free_percpu(net->core.inuse);
2841 }
2842
2843 static struct pernet_operations net_inuse_ops = {
2844 .init = sock_inuse_init_net,
2845 .exit = sock_inuse_exit_net,
2846 };
2847
2848 static __init int net_inuse_init(void)
2849 {
2850 if (register_pernet_subsys(&net_inuse_ops))
2851 panic("Cannot initialize net inuse counters");
2852
2853 return 0;
2854 }
2855
2856 core_initcall(net_inuse_init);
2857 #else
2858 static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
2859
2860 void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
2861 {
2862 __this_cpu_add(prot_inuse.val[prot->inuse_idx], val);
2863 }
2864 EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
2865
2866 int sock_prot_inuse_get(struct net *net, struct proto *prot)
2867 {
2868 int cpu, idx = prot->inuse_idx;
2869 int res = 0;
2870
2871 for_each_possible_cpu(cpu)
2872 res += per_cpu(prot_inuse, cpu).val[idx];
2873
2874 return res >= 0 ? res : 0;
2875 }
2876 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
2877 #endif
2878
2879 static void assign_proto_idx(struct proto *prot)
2880 {
2881 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
2882
2883 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
2884 pr_err("PROTO_INUSE_NR exhausted\n");
2885 return;
2886 }
2887
2888 set_bit(prot->inuse_idx, proto_inuse_idx);
2889 }
2890
2891 static void release_proto_idx(struct proto *prot)
2892 {
2893 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
2894 clear_bit(prot->inuse_idx, proto_inuse_idx);
2895 }
2896 #else
2897 static inline void assign_proto_idx(struct proto *prot)
2898 {
2899 }
2900
2901 static inline void release_proto_idx(struct proto *prot)
2902 {
2903 }
2904 #endif
2905
2906 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
2907 {
2908 if (!rsk_prot)
2909 return;
2910 kfree(rsk_prot->slab_name);
2911 rsk_prot->slab_name = NULL;
2912 kmem_cache_destroy(rsk_prot->slab);
2913 rsk_prot->slab = NULL;
2914 }
2915
2916 static int req_prot_init(const struct proto *prot)
2917 {
2918 struct request_sock_ops *rsk_prot = prot->rsk_prot;
2919
2920 if (!rsk_prot)
2921 return 0;
2922
2923 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
2924 prot->name);
2925 if (!rsk_prot->slab_name)
2926 return -ENOMEM;
2927
2928 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
2929 rsk_prot->obj_size, 0,
2930 prot->slab_flags, NULL);
2931
2932 if (!rsk_prot->slab) {
2933 pr_crit("%s: Can't create request sock SLAB cache!\n",
2934 prot->name);
2935 return -ENOMEM;
2936 }
2937 return 0;
2938 }
2939
2940 int proto_register(struct proto *prot, int alloc_slab)
2941 {
2942 if (alloc_slab) {
2943 prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0,
2944 SLAB_HWCACHE_ALIGN | prot->slab_flags,
2945 NULL);
2946
2947 if (prot->slab == NULL) {
2948 pr_crit("%s: Can't create sock SLAB cache!\n",
2949 prot->name);
2950 goto out;
2951 }
2952
2953 if (req_prot_init(prot))
2954 goto out_free_request_sock_slab;
2955
2956 if (prot->twsk_prot != NULL) {
2957 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
2958
2959 if (prot->twsk_prot->twsk_slab_name == NULL)
2960 goto out_free_request_sock_slab;
2961
2962 prot->twsk_prot->twsk_slab =
2963 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
2964 prot->twsk_prot->twsk_obj_size,
2965 0,
2966 prot->slab_flags,
2967 NULL);
2968 if (prot->twsk_prot->twsk_slab == NULL)
2969 goto out_free_timewait_sock_slab_name;
2970 }
2971 }
2972
2973 mutex_lock(&proto_list_mutex);
2974 list_add(&prot->node, &proto_list);
2975 assign_proto_idx(prot);
2976 mutex_unlock(&proto_list_mutex);
2977 return 0;
2978
2979 out_free_timewait_sock_slab_name:
2980 kfree(prot->twsk_prot->twsk_slab_name);
2981 out_free_request_sock_slab:
2982 req_prot_cleanup(prot->rsk_prot);
2983
2984 kmem_cache_destroy(prot->slab);
2985 prot->slab = NULL;
2986 out:
2987 return -ENOBUFS;
2988 }
2989 EXPORT_SYMBOL(proto_register);
2990
2991 void proto_unregister(struct proto *prot)
2992 {
2993 mutex_lock(&proto_list_mutex);
2994 release_proto_idx(prot);
2995 list_del(&prot->node);
2996 mutex_unlock(&proto_list_mutex);
2997
2998 kmem_cache_destroy(prot->slab);
2999 prot->slab = NULL;
3000
3001 req_prot_cleanup(prot->rsk_prot);
3002
3003 if (prot->twsk_prot != NULL && prot->twsk_prot->twsk_slab != NULL) {
3004 kmem_cache_destroy(prot->twsk_prot->twsk_slab);
3005 kfree(prot->twsk_prot->twsk_slab_name);
3006 prot->twsk_prot->twsk_slab = NULL;
3007 }
3008 }
3009 EXPORT_SYMBOL(proto_unregister);
3010
3011 #ifdef CONFIG_PROC_FS
3012 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3013 __acquires(proto_list_mutex)
3014 {
3015 mutex_lock(&proto_list_mutex);
3016 return seq_list_start_head(&proto_list, *pos);
3017 }
3018
3019 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3020 {
3021 return seq_list_next(v, &proto_list, pos);
3022 }
3023
3024 static void proto_seq_stop(struct seq_file *seq, void *v)
3025 __releases(proto_list_mutex)
3026 {
3027 mutex_unlock(&proto_list_mutex);
3028 }
3029
3030 static char proto_method_implemented(const void *method)
3031 {
3032 return method == NULL ? 'n' : 'y';
3033 }
3034 static long sock_prot_memory_allocated(struct proto *proto)
3035 {
3036 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3037 }
3038
3039 static char *sock_prot_memory_pressure(struct proto *proto)
3040 {
3041 return proto->memory_pressure != NULL ?
3042 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3043 }
3044
3045 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3046 {
3047
3048 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
3049 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3050 proto->name,
3051 proto->obj_size,
3052 sock_prot_inuse_get(seq_file_net(seq), proto),
3053 sock_prot_memory_allocated(proto),
3054 sock_prot_memory_pressure(proto),
3055 proto->max_header,
3056 proto->slab == NULL ? "no" : "yes",
3057 module_name(proto->owner),
3058 proto_method_implemented(proto->close),
3059 proto_method_implemented(proto->connect),
3060 proto_method_implemented(proto->disconnect),
3061 proto_method_implemented(proto->accept),
3062 proto_method_implemented(proto->ioctl),
3063 proto_method_implemented(proto->init),
3064 proto_method_implemented(proto->destroy),
3065 proto_method_implemented(proto->shutdown),
3066 proto_method_implemented(proto->setsockopt),
3067 proto_method_implemented(proto->getsockopt),
3068 proto_method_implemented(proto->sendmsg),
3069 proto_method_implemented(proto->recvmsg),
3070 proto_method_implemented(proto->sendpage),
3071 proto_method_implemented(proto->bind),
3072 proto_method_implemented(proto->backlog_rcv),
3073 proto_method_implemented(proto->hash),
3074 proto_method_implemented(proto->unhash),
3075 proto_method_implemented(proto->get_port),
3076 proto_method_implemented(proto->enter_memory_pressure));
3077 }
3078
3079 static int proto_seq_show(struct seq_file *seq, void *v)
3080 {
3081 if (v == &proto_list)
3082 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3083 "protocol",
3084 "size",
3085 "sockets",
3086 "memory",
3087 "press",
3088 "maxhdr",
3089 "slab",
3090 "module",
3091 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3092 else
3093 proto_seq_printf(seq, list_entry(v, struct proto, node));
3094 return 0;
3095 }
3096
3097 static const struct seq_operations proto_seq_ops = {
3098 .start = proto_seq_start,
3099 .next = proto_seq_next,
3100 .stop = proto_seq_stop,
3101 .show = proto_seq_show,
3102 };
3103
3104 static int proto_seq_open(struct inode *inode, struct file *file)
3105 {
3106 return seq_open_net(inode, file, &proto_seq_ops,
3107 sizeof(struct seq_net_private));
3108 }
3109
3110 static const struct file_operations proto_seq_fops = {
3111 .owner = THIS_MODULE,
3112 .open = proto_seq_open,
3113 .read = seq_read,
3114 .llseek = seq_lseek,
3115 .release = seq_release_net,
3116 };
3117
3118 static __net_init int proto_init_net(struct net *net)
3119 {
3120 if (!proc_create("protocols", S_IRUGO, net->proc_net, &proto_seq_fops))
3121 return -ENOMEM;
3122
3123 return 0;
3124 }
3125
3126 static __net_exit void proto_exit_net(struct net *net)
3127 {
3128 remove_proc_entry("protocols", net->proc_net);
3129 }
3130
3131
3132 static __net_initdata struct pernet_operations proto_net_ops = {
3133 .init = proto_init_net,
3134 .exit = proto_exit_net,
3135 };
3136
3137 static int __init proto_init(void)
3138 {
3139 return register_pernet_subsys(&proto_net_ops);
3140 }
3141
3142 subsys_initcall(proto_init);
3143
3144 #endif /* PROC_FS */
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