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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Generic socket support routines. Memory allocators, socket lock/release
8 * handler for protocols to use and generic option handler.
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
87
88#include <asm/unaligned.h>
89#include <linux/capability.h>
90#include <linux/errno.h>
91#include <linux/errqueue.h>
92#include <linux/types.h>
93#include <linux/socket.h>
94#include <linux/in.h>
95#include <linux/kernel.h>
96#include <linux/module.h>
97#include <linux/proc_fs.h>
98#include <linux/seq_file.h>
99#include <linux/sched.h>
100#include <linux/sched/mm.h>
101#include <linux/timer.h>
102#include <linux/string.h>
103#include <linux/sockios.h>
104#include <linux/net.h>
105#include <linux/mm.h>
106#include <linux/slab.h>
107#include <linux/interrupt.h>
108#include <linux/poll.h>
109#include <linux/tcp.h>
110#include <linux/udp.h>
111#include <linux/init.h>
112#include <linux/highmem.h>
113#include <linux/user_namespace.h>
114#include <linux/static_key.h>
115#include <linux/memcontrol.h>
116#include <linux/prefetch.h>
117#include <linux/compat.h>
118#include <linux/mroute.h>
119#include <linux/mroute6.h>
120#include <linux/icmpv6.h>
121
122#include <linux/uaccess.h>
123
124#include <linux/netdevice.h>
125#include <net/protocol.h>
126#include <linux/skbuff.h>
127#include <net/net_namespace.h>
128#include <net/request_sock.h>
129#include <net/sock.h>
130#include <linux/net_tstamp.h>
131#include <net/xfrm.h>
132#include <linux/ipsec.h>
133#include <net/cls_cgroup.h>
134#include <net/netprio_cgroup.h>
135#include <linux/sock_diag.h>
136
137#include <linux/filter.h>
138#include <net/sock_reuseport.h>
139#include <net/bpf_sk_storage.h>
140
141#include <trace/events/sock.h>
142
143#include <net/tcp.h>
144#include <net/busy_poll.h>
145#include <net/phonet/phonet.h>
146
147#include <linux/ethtool.h>
148
149#include "dev.h"
150
151static DEFINE_MUTEX(proto_list_mutex);
152static LIST_HEAD(proto_list);
153
154static void sock_def_write_space_wfree(struct sock *sk);
155static void sock_def_write_space(struct sock *sk);
156
157/**
158 * sk_ns_capable - General socket capability test
159 * @sk: Socket to use a capability on or through
160 * @user_ns: The user namespace of the capability to use
161 * @cap: The capability to use
162 *
163 * Test to see if the opener of the socket had when the socket was
164 * created and the current process has the capability @cap in the user
165 * namespace @user_ns.
166 */
167bool sk_ns_capable(const struct sock *sk,
168 struct user_namespace *user_ns, int cap)
169{
170 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
171 ns_capable(user_ns, cap);
172}
173EXPORT_SYMBOL(sk_ns_capable);
174
175/**
176 * sk_capable - Socket global capability test
177 * @sk: Socket to use a capability on or through
178 * @cap: The global capability to use
179 *
180 * Test to see if the opener of the socket had when the socket was
181 * created and the current process has the capability @cap in all user
182 * namespaces.
183 */
184bool sk_capable(const struct sock *sk, int cap)
185{
186 return sk_ns_capable(sk, &init_user_ns, cap);
187}
188EXPORT_SYMBOL(sk_capable);
189
190/**
191 * sk_net_capable - Network namespace socket capability test
192 * @sk: Socket to use a capability on or through
193 * @cap: The capability to use
194 *
195 * Test to see if the opener of the socket had when the socket was created
196 * and the current process has the capability @cap over the network namespace
197 * the socket is a member of.
198 */
199bool sk_net_capable(const struct sock *sk, int cap)
200{
201 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
202}
203EXPORT_SYMBOL(sk_net_capable);
204
205/*
206 * Each address family might have different locking rules, so we have
207 * one slock key per address family and separate keys for internal and
208 * userspace sockets.
209 */
210static struct lock_class_key af_family_keys[AF_MAX];
211static struct lock_class_key af_family_kern_keys[AF_MAX];
212static struct lock_class_key af_family_slock_keys[AF_MAX];
213static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
214
215/*
216 * Make lock validator output more readable. (we pre-construct these
217 * strings build-time, so that runtime initialization of socket
218 * locks is fast):
219 */
220
221#define _sock_locks(x) \
222 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \
223 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \
224 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \
225 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \
226 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \
227 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \
228 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \
229 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \
230 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \
231 x "27" , x "28" , x "AF_CAN" , \
232 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \
233 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \
234 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \
235 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \
236 x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \
237 x "AF_MCTP" , \
238 x "AF_MAX"
239
240static const char *const af_family_key_strings[AF_MAX+1] = {
241 _sock_locks("sk_lock-")
242};
243static const char *const af_family_slock_key_strings[AF_MAX+1] = {
244 _sock_locks("slock-")
245};
246static const char *const af_family_clock_key_strings[AF_MAX+1] = {
247 _sock_locks("clock-")
248};
249
250static const char *const af_family_kern_key_strings[AF_MAX+1] = {
251 _sock_locks("k-sk_lock-")
252};
253static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
254 _sock_locks("k-slock-")
255};
256static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
257 _sock_locks("k-clock-")
258};
259static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
260 _sock_locks("rlock-")
261};
262static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
263 _sock_locks("wlock-")
264};
265static const char *const af_family_elock_key_strings[AF_MAX+1] = {
266 _sock_locks("elock-")
267};
268
269/*
270 * sk_callback_lock and sk queues locking rules are per-address-family,
271 * so split the lock classes by using a per-AF key:
272 */
273static struct lock_class_key af_callback_keys[AF_MAX];
274static struct lock_class_key af_rlock_keys[AF_MAX];
275static struct lock_class_key af_wlock_keys[AF_MAX];
276static struct lock_class_key af_elock_keys[AF_MAX];
277static struct lock_class_key af_kern_callback_keys[AF_MAX];
278
279/* Run time adjustable parameters. */
280__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
281EXPORT_SYMBOL(sysctl_wmem_max);
282__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
283EXPORT_SYMBOL(sysctl_rmem_max);
284__u32 sysctl_wmem_default __read_mostly = SK_WMEM_MAX;
285__u32 sysctl_rmem_default __read_mostly = SK_RMEM_MAX;
286
287int sysctl_tstamp_allow_data __read_mostly = 1;
288
289DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
290EXPORT_SYMBOL_GPL(memalloc_socks_key);
291
292/**
293 * sk_set_memalloc - sets %SOCK_MEMALLOC
294 * @sk: socket to set it on
295 *
296 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
297 * It's the responsibility of the admin to adjust min_free_kbytes
298 * to meet the requirements
299 */
300void sk_set_memalloc(struct sock *sk)
301{
302 sock_set_flag(sk, SOCK_MEMALLOC);
303 sk->sk_allocation |= __GFP_MEMALLOC;
304 static_branch_inc(&memalloc_socks_key);
305}
306EXPORT_SYMBOL_GPL(sk_set_memalloc);
307
308void sk_clear_memalloc(struct sock *sk)
309{
310 sock_reset_flag(sk, SOCK_MEMALLOC);
311 sk->sk_allocation &= ~__GFP_MEMALLOC;
312 static_branch_dec(&memalloc_socks_key);
313
314 /*
315 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
316 * progress of swapping. SOCK_MEMALLOC may be cleared while
317 * it has rmem allocations due to the last swapfile being deactivated
318 * but there is a risk that the socket is unusable due to exceeding
319 * the rmem limits. Reclaim the reserves and obey rmem limits again.
320 */
321 sk_mem_reclaim(sk);
322}
323EXPORT_SYMBOL_GPL(sk_clear_memalloc);
324
325int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
326{
327 int ret;
328 unsigned int noreclaim_flag;
329
330 /* these should have been dropped before queueing */
331 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
332
333 noreclaim_flag = memalloc_noreclaim_save();
334 ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
335 tcp_v6_do_rcv,
336 tcp_v4_do_rcv,
337 sk, skb);
338 memalloc_noreclaim_restore(noreclaim_flag);
339
340 return ret;
341}
342EXPORT_SYMBOL(__sk_backlog_rcv);
343
344void sk_error_report(struct sock *sk)
345{
346 sk->sk_error_report(sk);
347
348 switch (sk->sk_family) {
349 case AF_INET:
350 fallthrough;
351 case AF_INET6:
352 trace_inet_sk_error_report(sk);
353 break;
354 default:
355 break;
356 }
357}
358EXPORT_SYMBOL(sk_error_report);
359
360int sock_get_timeout(long timeo, void *optval, bool old_timeval)
361{
362 struct __kernel_sock_timeval tv;
363
364 if (timeo == MAX_SCHEDULE_TIMEOUT) {
365 tv.tv_sec = 0;
366 tv.tv_usec = 0;
367 } else {
368 tv.tv_sec = timeo / HZ;
369 tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
370 }
371
372 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
373 struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
374 *(struct old_timeval32 *)optval = tv32;
375 return sizeof(tv32);
376 }
377
378 if (old_timeval) {
379 struct __kernel_old_timeval old_tv;
380 old_tv.tv_sec = tv.tv_sec;
381 old_tv.tv_usec = tv.tv_usec;
382 *(struct __kernel_old_timeval *)optval = old_tv;
383 return sizeof(old_tv);
384 }
385
386 *(struct __kernel_sock_timeval *)optval = tv;
387 return sizeof(tv);
388}
389EXPORT_SYMBOL(sock_get_timeout);
390
391int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
392 sockptr_t optval, int optlen, bool old_timeval)
393{
394 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
395 struct old_timeval32 tv32;
396
397 if (optlen < sizeof(tv32))
398 return -EINVAL;
399
400 if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
401 return -EFAULT;
402 tv->tv_sec = tv32.tv_sec;
403 tv->tv_usec = tv32.tv_usec;
404 } else if (old_timeval) {
405 struct __kernel_old_timeval old_tv;
406
407 if (optlen < sizeof(old_tv))
408 return -EINVAL;
409 if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
410 return -EFAULT;
411 tv->tv_sec = old_tv.tv_sec;
412 tv->tv_usec = old_tv.tv_usec;
413 } else {
414 if (optlen < sizeof(*tv))
415 return -EINVAL;
416 if (copy_from_sockptr(tv, optval, sizeof(*tv)))
417 return -EFAULT;
418 }
419
420 return 0;
421}
422EXPORT_SYMBOL(sock_copy_user_timeval);
423
424static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
425 bool old_timeval)
426{
427 struct __kernel_sock_timeval tv;
428 int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
429 long val;
430
431 if (err)
432 return err;
433
434 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
435 return -EDOM;
436
437 if (tv.tv_sec < 0) {
438 static int warned __read_mostly;
439
440 WRITE_ONCE(*timeo_p, 0);
441 if (warned < 10 && net_ratelimit()) {
442 warned++;
443 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
444 __func__, current->comm, task_pid_nr(current));
445 }
446 return 0;
447 }
448 val = MAX_SCHEDULE_TIMEOUT;
449 if ((tv.tv_sec || tv.tv_usec) &&
450 (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))
451 val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,
452 USEC_PER_SEC / HZ);
453 WRITE_ONCE(*timeo_p, val);
454 return 0;
455}
456
457static bool sock_needs_netstamp(const struct sock *sk)
458{
459 switch (sk->sk_family) {
460 case AF_UNSPEC:
461 case AF_UNIX:
462 return false;
463 default:
464 return true;
465 }
466}
467
468static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
469{
470 if (sk->sk_flags & flags) {
471 sk->sk_flags &= ~flags;
472 if (sock_needs_netstamp(sk) &&
473 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
474 net_disable_timestamp();
475 }
476}
477
478
479int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
480{
481 unsigned long flags;
482 struct sk_buff_head *list = &sk->sk_receive_queue;
483
484 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
485 atomic_inc(&sk->sk_drops);
486 trace_sock_rcvqueue_full(sk, skb);
487 return -ENOMEM;
488 }
489
490 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
491 atomic_inc(&sk->sk_drops);
492 return -ENOBUFS;
493 }
494
495 skb->dev = NULL;
496 skb_set_owner_r(skb, sk);
497
498 /* we escape from rcu protected region, make sure we dont leak
499 * a norefcounted dst
500 */
501 skb_dst_force(skb);
502
503 spin_lock_irqsave(&list->lock, flags);
504 sock_skb_set_dropcount(sk, skb);
505 __skb_queue_tail(list, skb);
506 spin_unlock_irqrestore(&list->lock, flags);
507
508 if (!sock_flag(sk, SOCK_DEAD))
509 sk->sk_data_ready(sk);
510 return 0;
511}
512EXPORT_SYMBOL(__sock_queue_rcv_skb);
513
514int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
515 enum skb_drop_reason *reason)
516{
517 enum skb_drop_reason drop_reason;
518 int err;
519
520 err = sk_filter(sk, skb);
521 if (err) {
522 drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
523 goto out;
524 }
525 err = __sock_queue_rcv_skb(sk, skb);
526 switch (err) {
527 case -ENOMEM:
528 drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
529 break;
530 case -ENOBUFS:
531 drop_reason = SKB_DROP_REASON_PROTO_MEM;
532 break;
533 default:
534 drop_reason = SKB_NOT_DROPPED_YET;
535 break;
536 }
537out:
538 if (reason)
539 *reason = drop_reason;
540 return err;
541}
542EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
543
544int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
545 const int nested, unsigned int trim_cap, bool refcounted)
546{
547 int rc = NET_RX_SUCCESS;
548
549 if (sk_filter_trim_cap(sk, skb, trim_cap))
550 goto discard_and_relse;
551
552 skb->dev = NULL;
553
554 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
555 atomic_inc(&sk->sk_drops);
556 goto discard_and_relse;
557 }
558 if (nested)
559 bh_lock_sock_nested(sk);
560 else
561 bh_lock_sock(sk);
562 if (!sock_owned_by_user(sk)) {
563 /*
564 * trylock + unlock semantics:
565 */
566 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
567
568 rc = sk_backlog_rcv(sk, skb);
569
570 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
571 } else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
572 bh_unlock_sock(sk);
573 atomic_inc(&sk->sk_drops);
574 goto discard_and_relse;
575 }
576
577 bh_unlock_sock(sk);
578out:
579 if (refcounted)
580 sock_put(sk);
581 return rc;
582discard_and_relse:
583 kfree_skb(skb);
584 goto out;
585}
586EXPORT_SYMBOL(__sk_receive_skb);
587
588INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
589 u32));
590INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
591 u32));
592struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
593{
594 struct dst_entry *dst = __sk_dst_get(sk);
595
596 if (dst && dst->obsolete &&
597 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
598 dst, cookie) == NULL) {
599 sk_tx_queue_clear(sk);
600 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
601 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
602 dst_release(dst);
603 return NULL;
604 }
605
606 return dst;
607}
608EXPORT_SYMBOL(__sk_dst_check);
609
610struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
611{
612 struct dst_entry *dst = sk_dst_get(sk);
613
614 if (dst && dst->obsolete &&
615 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
616 dst, cookie) == NULL) {
617 sk_dst_reset(sk);
618 dst_release(dst);
619 return NULL;
620 }
621
622 return dst;
623}
624EXPORT_SYMBOL(sk_dst_check);
625
626static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
627{
628 int ret = -ENOPROTOOPT;
629#ifdef CONFIG_NETDEVICES
630 struct net *net = sock_net(sk);
631
632 /* Sorry... */
633 ret = -EPERM;
634 if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
635 goto out;
636
637 ret = -EINVAL;
638 if (ifindex < 0)
639 goto out;
640
641 /* Paired with all READ_ONCE() done locklessly. */
642 WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
643
644 if (sk->sk_prot->rehash)
645 sk->sk_prot->rehash(sk);
646 sk_dst_reset(sk);
647
648 ret = 0;
649
650out:
651#endif
652
653 return ret;
654}
655
656int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
657{
658 int ret;
659
660 if (lock_sk)
661 lock_sock(sk);
662 ret = sock_bindtoindex_locked(sk, ifindex);
663 if (lock_sk)
664 release_sock(sk);
665
666 return ret;
667}
668EXPORT_SYMBOL(sock_bindtoindex);
669
670static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
671{
672 int ret = -ENOPROTOOPT;
673#ifdef CONFIG_NETDEVICES
674 struct net *net = sock_net(sk);
675 char devname[IFNAMSIZ];
676 int index;
677
678 ret = -EINVAL;
679 if (optlen < 0)
680 goto out;
681
682 /* Bind this socket to a particular device like "eth0",
683 * as specified in the passed interface name. If the
684 * name is "" or the option length is zero the socket
685 * is not bound.
686 */
687 if (optlen > IFNAMSIZ - 1)
688 optlen = IFNAMSIZ - 1;
689 memset(devname, 0, sizeof(devname));
690
691 ret = -EFAULT;
692 if (copy_from_sockptr(devname, optval, optlen))
693 goto out;
694
695 index = 0;
696 if (devname[0] != '\0') {
697 struct net_device *dev;
698
699 rcu_read_lock();
700 dev = dev_get_by_name_rcu(net, devname);
701 if (dev)
702 index = dev->ifindex;
703 rcu_read_unlock();
704 ret = -ENODEV;
705 if (!dev)
706 goto out;
707 }
708
709 sockopt_lock_sock(sk);
710 ret = sock_bindtoindex_locked(sk, index);
711 sockopt_release_sock(sk);
712out:
713#endif
714
715 return ret;
716}
717
718static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
719 sockptr_t optlen, int len)
720{
721 int ret = -ENOPROTOOPT;
722#ifdef CONFIG_NETDEVICES
723 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
724 struct net *net = sock_net(sk);
725 char devname[IFNAMSIZ];
726
727 if (bound_dev_if == 0) {
728 len = 0;
729 goto zero;
730 }
731
732 ret = -EINVAL;
733 if (len < IFNAMSIZ)
734 goto out;
735
736 ret = netdev_get_name(net, devname, bound_dev_if);
737 if (ret)
738 goto out;
739
740 len = strlen(devname) + 1;
741
742 ret = -EFAULT;
743 if (copy_to_sockptr(optval, devname, len))
744 goto out;
745
746zero:
747 ret = -EFAULT;
748 if (copy_to_sockptr(optlen, &len, sizeof(int)))
749 goto out;
750
751 ret = 0;
752
753out:
754#endif
755
756 return ret;
757}
758
759bool sk_mc_loop(const struct sock *sk)
760{
761 if (dev_recursion_level())
762 return false;
763 if (!sk)
764 return true;
765 /* IPV6_ADDRFORM can change sk->sk_family under us. */
766 switch (READ_ONCE(sk->sk_family)) {
767 case AF_INET:
768 return inet_test_bit(MC_LOOP, sk);
769#if IS_ENABLED(CONFIG_IPV6)
770 case AF_INET6:
771 return inet6_test_bit(MC6_LOOP, sk);
772#endif
773 }
774 WARN_ON_ONCE(1);
775 return true;
776}
777EXPORT_SYMBOL(sk_mc_loop);
778
779void sock_set_reuseaddr(struct sock *sk)
780{
781 lock_sock(sk);
782 sk->sk_reuse = SK_CAN_REUSE;
783 release_sock(sk);
784}
785EXPORT_SYMBOL(sock_set_reuseaddr);
786
787void sock_set_reuseport(struct sock *sk)
788{
789 lock_sock(sk);
790 sk->sk_reuseport = true;
791 release_sock(sk);
792}
793EXPORT_SYMBOL(sock_set_reuseport);
794
795void sock_no_linger(struct sock *sk)
796{
797 lock_sock(sk);
798 WRITE_ONCE(sk->sk_lingertime, 0);
799 sock_set_flag(sk, SOCK_LINGER);
800 release_sock(sk);
801}
802EXPORT_SYMBOL(sock_no_linger);
803
804void sock_set_priority(struct sock *sk, u32 priority)
805{
806 WRITE_ONCE(sk->sk_priority, priority);
807}
808EXPORT_SYMBOL(sock_set_priority);
809
810void sock_set_sndtimeo(struct sock *sk, s64 secs)
811{
812 lock_sock(sk);
813 if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
814 WRITE_ONCE(sk->sk_sndtimeo, secs * HZ);
815 else
816 WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT);
817 release_sock(sk);
818}
819EXPORT_SYMBOL(sock_set_sndtimeo);
820
821static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
822{
823 if (val) {
824 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
825 sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
826 sock_set_flag(sk, SOCK_RCVTSTAMP);
827 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
828 } else {
829 sock_reset_flag(sk, SOCK_RCVTSTAMP);
830 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
831 }
832}
833
834void sock_enable_timestamps(struct sock *sk)
835{
836 lock_sock(sk);
837 __sock_set_timestamps(sk, true, false, true);
838 release_sock(sk);
839}
840EXPORT_SYMBOL(sock_enable_timestamps);
841
842void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
843{
844 switch (optname) {
845 case SO_TIMESTAMP_OLD:
846 __sock_set_timestamps(sk, valbool, false, false);
847 break;
848 case SO_TIMESTAMP_NEW:
849 __sock_set_timestamps(sk, valbool, true, false);
850 break;
851 case SO_TIMESTAMPNS_OLD:
852 __sock_set_timestamps(sk, valbool, false, true);
853 break;
854 case SO_TIMESTAMPNS_NEW:
855 __sock_set_timestamps(sk, valbool, true, true);
856 break;
857 }
858}
859
860static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
861{
862 struct net *net = sock_net(sk);
863 struct net_device *dev = NULL;
864 bool match = false;
865 int *vclock_index;
866 int i, num;
867
868 if (sk->sk_bound_dev_if)
869 dev = dev_get_by_index(net, sk->sk_bound_dev_if);
870
871 if (!dev) {
872 pr_err("%s: sock not bind to device\n", __func__);
873 return -EOPNOTSUPP;
874 }
875
876 num = ethtool_get_phc_vclocks(dev, &vclock_index);
877 dev_put(dev);
878
879 for (i = 0; i < num; i++) {
880 if (*(vclock_index + i) == phc_index) {
881 match = true;
882 break;
883 }
884 }
885
886 if (num > 0)
887 kfree(vclock_index);
888
889 if (!match)
890 return -EINVAL;
891
892 WRITE_ONCE(sk->sk_bind_phc, phc_index);
893
894 return 0;
895}
896
897int sock_set_timestamping(struct sock *sk, int optname,
898 struct so_timestamping timestamping)
899{
900 int val = timestamping.flags;
901 int ret;
902
903 if (val & ~SOF_TIMESTAMPING_MASK)
904 return -EINVAL;
905
906 if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
907 !(val & SOF_TIMESTAMPING_OPT_ID))
908 return -EINVAL;
909
910 if (val & SOF_TIMESTAMPING_OPT_ID &&
911 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
912 if (sk_is_tcp(sk)) {
913 if ((1 << sk->sk_state) &
914 (TCPF_CLOSE | TCPF_LISTEN))
915 return -EINVAL;
916 if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
917 atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
918 else
919 atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
920 } else {
921 atomic_set(&sk->sk_tskey, 0);
922 }
923 }
924
925 if (val & SOF_TIMESTAMPING_OPT_STATS &&
926 !(val & SOF_TIMESTAMPING_OPT_TSONLY))
927 return -EINVAL;
928
929 if (val & SOF_TIMESTAMPING_BIND_PHC) {
930 ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
931 if (ret)
932 return ret;
933 }
934
935 WRITE_ONCE(sk->sk_tsflags, val);
936 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
937
938 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
939 sock_enable_timestamp(sk,
940 SOCK_TIMESTAMPING_RX_SOFTWARE);
941 else
942 sock_disable_timestamp(sk,
943 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
944 return 0;
945}
946
947void sock_set_keepalive(struct sock *sk)
948{
949 lock_sock(sk);
950 if (sk->sk_prot->keepalive)
951 sk->sk_prot->keepalive(sk, true);
952 sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
953 release_sock(sk);
954}
955EXPORT_SYMBOL(sock_set_keepalive);
956
957static void __sock_set_rcvbuf(struct sock *sk, int val)
958{
959 /* Ensure val * 2 fits into an int, to prevent max_t() from treating it
960 * as a negative value.
961 */
962 val = min_t(int, val, INT_MAX / 2);
963 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
964
965 /* We double it on the way in to account for "struct sk_buff" etc.
966 * overhead. Applications assume that the SO_RCVBUF setting they make
967 * will allow that much actual data to be received on that socket.
968 *
969 * Applications are unaware that "struct sk_buff" and other overheads
970 * allocate from the receive buffer during socket buffer allocation.
971 *
972 * And after considering the possible alternatives, returning the value
973 * we actually used in getsockopt is the most desirable behavior.
974 */
975 WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
976}
977
978void sock_set_rcvbuf(struct sock *sk, int val)
979{
980 lock_sock(sk);
981 __sock_set_rcvbuf(sk, val);
982 release_sock(sk);
983}
984EXPORT_SYMBOL(sock_set_rcvbuf);
985
986static void __sock_set_mark(struct sock *sk, u32 val)
987{
988 if (val != sk->sk_mark) {
989 WRITE_ONCE(sk->sk_mark, val);
990 sk_dst_reset(sk);
991 }
992}
993
994void sock_set_mark(struct sock *sk, u32 val)
995{
996 lock_sock(sk);
997 __sock_set_mark(sk, val);
998 release_sock(sk);
999}
1000EXPORT_SYMBOL(sock_set_mark);
1001
1002static void sock_release_reserved_memory(struct sock *sk, int bytes)
1003{
1004 /* Round down bytes to multiple of pages */
1005 bytes = round_down(bytes, PAGE_SIZE);
1006
1007 WARN_ON(bytes > sk->sk_reserved_mem);
1008 WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes);
1009 sk_mem_reclaim(sk);
1010}
1011
1012static int sock_reserve_memory(struct sock *sk, int bytes)
1013{
1014 long allocated;
1015 bool charged;
1016 int pages;
1017
1018 if (!mem_cgroup_sockets_enabled || !sk->sk_memcg || !sk_has_account(sk))
1019 return -EOPNOTSUPP;
1020
1021 if (!bytes)
1022 return 0;
1023
1024 pages = sk_mem_pages(bytes);
1025
1026 /* pre-charge to memcg */
1027 charged = mem_cgroup_charge_skmem(sk->sk_memcg, pages,
1028 GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1029 if (!charged)
1030 return -ENOMEM;
1031
1032 /* pre-charge to forward_alloc */
1033 sk_memory_allocated_add(sk, pages);
1034 allocated = sk_memory_allocated(sk);
1035 /* If the system goes into memory pressure with this
1036 * precharge, give up and return error.
1037 */
1038 if (allocated > sk_prot_mem_limits(sk, 1)) {
1039 sk_memory_allocated_sub(sk, pages);
1040 mem_cgroup_uncharge_skmem(sk->sk_memcg, pages);
1041 return -ENOMEM;
1042 }
1043 sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1044
1045 WRITE_ONCE(sk->sk_reserved_mem,
1046 sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1047
1048 return 0;
1049}
1050
1051void sockopt_lock_sock(struct sock *sk)
1052{
1053 /* When current->bpf_ctx is set, the setsockopt is called from
1054 * a bpf prog. bpf has ensured the sk lock has been
1055 * acquired before calling setsockopt().
1056 */
1057 if (has_current_bpf_ctx())
1058 return;
1059
1060 lock_sock(sk);
1061}
1062EXPORT_SYMBOL(sockopt_lock_sock);
1063
1064void sockopt_release_sock(struct sock *sk)
1065{
1066 if (has_current_bpf_ctx())
1067 return;
1068
1069 release_sock(sk);
1070}
1071EXPORT_SYMBOL(sockopt_release_sock);
1072
1073bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1074{
1075 return has_current_bpf_ctx() || ns_capable(ns, cap);
1076}
1077EXPORT_SYMBOL(sockopt_ns_capable);
1078
1079bool sockopt_capable(int cap)
1080{
1081 return has_current_bpf_ctx() || capable(cap);
1082}
1083EXPORT_SYMBOL(sockopt_capable);
1084
1085/*
1086 * This is meant for all protocols to use and covers goings on
1087 * at the socket level. Everything here is generic.
1088 */
1089
1090int sk_setsockopt(struct sock *sk, int level, int optname,
1091 sockptr_t optval, unsigned int optlen)
1092{
1093 struct so_timestamping timestamping;
1094 struct socket *sock = sk->sk_socket;
1095 struct sock_txtime sk_txtime;
1096 int val;
1097 int valbool;
1098 struct linger ling;
1099 int ret = 0;
1100
1101 /*
1102 * Options without arguments
1103 */
1104
1105 if (optname == SO_BINDTODEVICE)
1106 return sock_setbindtodevice(sk, optval, optlen);
1107
1108 if (optlen < sizeof(int))
1109 return -EINVAL;
1110
1111 if (copy_from_sockptr(&val, optval, sizeof(val)))
1112 return -EFAULT;
1113
1114 valbool = val ? 1 : 0;
1115
1116 /* handle options which do not require locking the socket. */
1117 switch (optname) {
1118 case SO_PRIORITY:
1119 if ((val >= 0 && val <= 6) ||
1120 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
1121 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1122 sock_set_priority(sk, val);
1123 return 0;
1124 }
1125 return -EPERM;
1126 case SO_PASSSEC:
1127 assign_bit(SOCK_PASSSEC, &sock->flags, valbool);
1128 return 0;
1129 case SO_PASSCRED:
1130 assign_bit(SOCK_PASSCRED, &sock->flags, valbool);
1131 return 0;
1132 case SO_PASSPIDFD:
1133 assign_bit(SOCK_PASSPIDFD, &sock->flags, valbool);
1134 return 0;
1135 case SO_TYPE:
1136 case SO_PROTOCOL:
1137 case SO_DOMAIN:
1138 case SO_ERROR:
1139 return -ENOPROTOOPT;
1140#ifdef CONFIG_NET_RX_BUSY_POLL
1141 case SO_BUSY_POLL:
1142 if (val < 0)
1143 return -EINVAL;
1144 WRITE_ONCE(sk->sk_ll_usec, val);
1145 return 0;
1146 case SO_PREFER_BUSY_POLL:
1147 if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1148 return -EPERM;
1149 WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1150 return 0;
1151 case SO_BUSY_POLL_BUDGET:
1152 if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1153 !sockopt_capable(CAP_NET_ADMIN))
1154 return -EPERM;
1155 if (val < 0 || val > U16_MAX)
1156 return -EINVAL;
1157 WRITE_ONCE(sk->sk_busy_poll_budget, val);
1158 return 0;
1159#endif
1160 case SO_MAX_PACING_RATE:
1161 {
1162 unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1163 unsigned long pacing_rate;
1164
1165 if (sizeof(ulval) != sizeof(val) &&
1166 optlen >= sizeof(ulval) &&
1167 copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1168 return -EFAULT;
1169 }
1170 if (ulval != ~0UL)
1171 cmpxchg(&sk->sk_pacing_status,
1172 SK_PACING_NONE,
1173 SK_PACING_NEEDED);
1174 /* Pairs with READ_ONCE() from sk_getsockopt() */
1175 WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1176 pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1177 if (ulval < pacing_rate)
1178 WRITE_ONCE(sk->sk_pacing_rate, ulval);
1179 return 0;
1180 }
1181 case SO_TXREHASH:
1182 if (val < -1 || val > 1)
1183 return -EINVAL;
1184 if ((u8)val == SOCK_TXREHASH_DEFAULT)
1185 val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1186 /* Paired with READ_ONCE() in tcp_rtx_synack()
1187 * and sk_getsockopt().
1188 */
1189 WRITE_ONCE(sk->sk_txrehash, (u8)val);
1190 return 0;
1191 case SO_PEEK_OFF:
1192 {
1193 int (*set_peek_off)(struct sock *sk, int val);
1194
1195 set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1196 if (set_peek_off)
1197 ret = set_peek_off(sk, val);
1198 else
1199 ret = -EOPNOTSUPP;
1200 return ret;
1201 }
1202 }
1203
1204 sockopt_lock_sock(sk);
1205
1206 switch (optname) {
1207 case SO_DEBUG:
1208 if (val && !sockopt_capable(CAP_NET_ADMIN))
1209 ret = -EACCES;
1210 else
1211 sock_valbool_flag(sk, SOCK_DBG, valbool);
1212 break;
1213 case SO_REUSEADDR:
1214 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1215 break;
1216 case SO_REUSEPORT:
1217 sk->sk_reuseport = valbool;
1218 break;
1219 case SO_DONTROUTE:
1220 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1221 sk_dst_reset(sk);
1222 break;
1223 case SO_BROADCAST:
1224 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1225 break;
1226 case SO_SNDBUF:
1227 /* Don't error on this BSD doesn't and if you think
1228 * about it this is right. Otherwise apps have to
1229 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1230 * are treated in BSD as hints
1231 */
1232 val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1233set_sndbuf:
1234 /* Ensure val * 2 fits into an int, to prevent max_t()
1235 * from treating it as a negative value.
1236 */
1237 val = min_t(int, val, INT_MAX / 2);
1238 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1239 WRITE_ONCE(sk->sk_sndbuf,
1240 max_t(int, val * 2, SOCK_MIN_SNDBUF));
1241 /* Wake up sending tasks if we upped the value. */
1242 sk->sk_write_space(sk);
1243 break;
1244
1245 case SO_SNDBUFFORCE:
1246 if (!sockopt_capable(CAP_NET_ADMIN)) {
1247 ret = -EPERM;
1248 break;
1249 }
1250
1251 /* No negative values (to prevent underflow, as val will be
1252 * multiplied by 2).
1253 */
1254 if (val < 0)
1255 val = 0;
1256 goto set_sndbuf;
1257
1258 case SO_RCVBUF:
1259 /* Don't error on this BSD doesn't and if you think
1260 * about it this is right. Otherwise apps have to
1261 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1262 * are treated in BSD as hints
1263 */
1264 __sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1265 break;
1266
1267 case SO_RCVBUFFORCE:
1268 if (!sockopt_capable(CAP_NET_ADMIN)) {
1269 ret = -EPERM;
1270 break;
1271 }
1272
1273 /* No negative values (to prevent underflow, as val will be
1274 * multiplied by 2).
1275 */
1276 __sock_set_rcvbuf(sk, max(val, 0));
1277 break;
1278
1279 case SO_KEEPALIVE:
1280 if (sk->sk_prot->keepalive)
1281 sk->sk_prot->keepalive(sk, valbool);
1282 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1283 break;
1284
1285 case SO_OOBINLINE:
1286 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1287 break;
1288
1289 case SO_NO_CHECK:
1290 sk->sk_no_check_tx = valbool;
1291 break;
1292
1293 case SO_LINGER:
1294 if (optlen < sizeof(ling)) {
1295 ret = -EINVAL; /* 1003.1g */
1296 break;
1297 }
1298 if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1299 ret = -EFAULT;
1300 break;
1301 }
1302 if (!ling.l_onoff) {
1303 sock_reset_flag(sk, SOCK_LINGER);
1304 } else {
1305 unsigned long t_sec = ling.l_linger;
1306
1307 if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1308 WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1309 else
1310 WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
1311 sock_set_flag(sk, SOCK_LINGER);
1312 }
1313 break;
1314
1315 case SO_BSDCOMPAT:
1316 break;
1317
1318 case SO_TIMESTAMP_OLD:
1319 case SO_TIMESTAMP_NEW:
1320 case SO_TIMESTAMPNS_OLD:
1321 case SO_TIMESTAMPNS_NEW:
1322 sock_set_timestamp(sk, optname, valbool);
1323 break;
1324
1325 case SO_TIMESTAMPING_NEW:
1326 case SO_TIMESTAMPING_OLD:
1327 if (optlen == sizeof(timestamping)) {
1328 if (copy_from_sockptr(×tamping, optval,
1329 sizeof(timestamping))) {
1330 ret = -EFAULT;
1331 break;
1332 }
1333 } else {
1334 memset(×tamping, 0, sizeof(timestamping));
1335 timestamping.flags = val;
1336 }
1337 ret = sock_set_timestamping(sk, optname, timestamping);
1338 break;
1339
1340 case SO_RCVLOWAT:
1341 {
1342 int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
1343
1344 if (val < 0)
1345 val = INT_MAX;
1346 if (sock)
1347 set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1348 if (set_rcvlowat)
1349 ret = set_rcvlowat(sk, val);
1350 else
1351 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1352 break;
1353 }
1354 case SO_RCVTIMEO_OLD:
1355 case SO_RCVTIMEO_NEW:
1356 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1357 optlen, optname == SO_RCVTIMEO_OLD);
1358 break;
1359
1360 case SO_SNDTIMEO_OLD:
1361 case SO_SNDTIMEO_NEW:
1362 ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1363 optlen, optname == SO_SNDTIMEO_OLD);
1364 break;
1365
1366 case SO_ATTACH_FILTER: {
1367 struct sock_fprog fprog;
1368
1369 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1370 if (!ret)
1371 ret = sk_attach_filter(&fprog, sk);
1372 break;
1373 }
1374 case SO_ATTACH_BPF:
1375 ret = -EINVAL;
1376 if (optlen == sizeof(u32)) {
1377 u32 ufd;
1378
1379 ret = -EFAULT;
1380 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1381 break;
1382
1383 ret = sk_attach_bpf(ufd, sk);
1384 }
1385 break;
1386
1387 case SO_ATTACH_REUSEPORT_CBPF: {
1388 struct sock_fprog fprog;
1389
1390 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1391 if (!ret)
1392 ret = sk_reuseport_attach_filter(&fprog, sk);
1393 break;
1394 }
1395 case SO_ATTACH_REUSEPORT_EBPF:
1396 ret = -EINVAL;
1397 if (optlen == sizeof(u32)) {
1398 u32 ufd;
1399
1400 ret = -EFAULT;
1401 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1402 break;
1403
1404 ret = sk_reuseport_attach_bpf(ufd, sk);
1405 }
1406 break;
1407
1408 case SO_DETACH_REUSEPORT_BPF:
1409 ret = reuseport_detach_prog(sk);
1410 break;
1411
1412 case SO_DETACH_FILTER:
1413 ret = sk_detach_filter(sk);
1414 break;
1415
1416 case SO_LOCK_FILTER:
1417 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1418 ret = -EPERM;
1419 else
1420 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1421 break;
1422
1423 case SO_MARK:
1424 if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1425 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1426 ret = -EPERM;
1427 break;
1428 }
1429
1430 __sock_set_mark(sk, val);
1431 break;
1432 case SO_RCVMARK:
1433 sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1434 break;
1435
1436 case SO_RXQ_OVFL:
1437 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1438 break;
1439
1440 case SO_WIFI_STATUS:
1441 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1442 break;
1443
1444 case SO_NOFCS:
1445 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1446 break;
1447
1448 case SO_SELECT_ERR_QUEUE:
1449 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1450 break;
1451
1452
1453 case SO_INCOMING_CPU:
1454 reuseport_update_incoming_cpu(sk, val);
1455 break;
1456
1457 case SO_CNX_ADVICE:
1458 if (val == 1)
1459 dst_negative_advice(sk);
1460 break;
1461
1462 case SO_ZEROCOPY:
1463 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1464 if (!(sk_is_tcp(sk) ||
1465 (sk->sk_type == SOCK_DGRAM &&
1466 sk->sk_protocol == IPPROTO_UDP)))
1467 ret = -EOPNOTSUPP;
1468 } else if (sk->sk_family != PF_RDS) {
1469 ret = -EOPNOTSUPP;
1470 }
1471 if (!ret) {
1472 if (val < 0 || val > 1)
1473 ret = -EINVAL;
1474 else
1475 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1476 }
1477 break;
1478
1479 case SO_TXTIME:
1480 if (optlen != sizeof(struct sock_txtime)) {
1481 ret = -EINVAL;
1482 break;
1483 } else if (copy_from_sockptr(&sk_txtime, optval,
1484 sizeof(struct sock_txtime))) {
1485 ret = -EFAULT;
1486 break;
1487 } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1488 ret = -EINVAL;
1489 break;
1490 }
1491 /* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1492 * scheduler has enough safe guards.
1493 */
1494 if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1495 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1496 ret = -EPERM;
1497 break;
1498 }
1499 sock_valbool_flag(sk, SOCK_TXTIME, true);
1500 sk->sk_clockid = sk_txtime.clockid;
1501 sk->sk_txtime_deadline_mode =
1502 !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1503 sk->sk_txtime_report_errors =
1504 !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1505 break;
1506
1507 case SO_BINDTOIFINDEX:
1508 ret = sock_bindtoindex_locked(sk, val);
1509 break;
1510
1511 case SO_BUF_LOCK:
1512 if (val & ~SOCK_BUF_LOCK_MASK) {
1513 ret = -EINVAL;
1514 break;
1515 }
1516 sk->sk_userlocks = val | (sk->sk_userlocks &
1517 ~SOCK_BUF_LOCK_MASK);
1518 break;
1519
1520 case SO_RESERVE_MEM:
1521 {
1522 int delta;
1523
1524 if (val < 0) {
1525 ret = -EINVAL;
1526 break;
1527 }
1528
1529 delta = val - sk->sk_reserved_mem;
1530 if (delta < 0)
1531 sock_release_reserved_memory(sk, -delta);
1532 else
1533 ret = sock_reserve_memory(sk, delta);
1534 break;
1535 }
1536
1537 default:
1538 ret = -ENOPROTOOPT;
1539 break;
1540 }
1541 sockopt_release_sock(sk);
1542 return ret;
1543}
1544
1545int sock_setsockopt(struct socket *sock, int level, int optname,
1546 sockptr_t optval, unsigned int optlen)
1547{
1548 return sk_setsockopt(sock->sk, level, optname,
1549 optval, optlen);
1550}
1551EXPORT_SYMBOL(sock_setsockopt);
1552
1553static const struct cred *sk_get_peer_cred(struct sock *sk)
1554{
1555 const struct cred *cred;
1556
1557 spin_lock(&sk->sk_peer_lock);
1558 cred = get_cred(sk->sk_peer_cred);
1559 spin_unlock(&sk->sk_peer_lock);
1560
1561 return cred;
1562}
1563
1564static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1565 struct ucred *ucred)
1566{
1567 ucred->pid = pid_vnr(pid);
1568 ucred->uid = ucred->gid = -1;
1569 if (cred) {
1570 struct user_namespace *current_ns = current_user_ns();
1571
1572 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1573 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1574 }
1575}
1576
1577static int groups_to_user(sockptr_t dst, const struct group_info *src)
1578{
1579 struct user_namespace *user_ns = current_user_ns();
1580 int i;
1581
1582 for (i = 0; i < src->ngroups; i++) {
1583 gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1584
1585 if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1586 return -EFAULT;
1587 }
1588
1589 return 0;
1590}
1591
1592int sk_getsockopt(struct sock *sk, int level, int optname,
1593 sockptr_t optval, sockptr_t optlen)
1594{
1595 struct socket *sock = sk->sk_socket;
1596
1597 union {
1598 int val;
1599 u64 val64;
1600 unsigned long ulval;
1601 struct linger ling;
1602 struct old_timeval32 tm32;
1603 struct __kernel_old_timeval tm;
1604 struct __kernel_sock_timeval stm;
1605 struct sock_txtime txtime;
1606 struct so_timestamping timestamping;
1607 } v;
1608
1609 int lv = sizeof(int);
1610 int len;
1611
1612 if (copy_from_sockptr(&len, optlen, sizeof(int)))
1613 return -EFAULT;
1614 if (len < 0)
1615 return -EINVAL;
1616
1617 memset(&v, 0, sizeof(v));
1618
1619 switch (optname) {
1620 case SO_DEBUG:
1621 v.val = sock_flag(sk, SOCK_DBG);
1622 break;
1623
1624 case SO_DONTROUTE:
1625 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1626 break;
1627
1628 case SO_BROADCAST:
1629 v.val = sock_flag(sk, SOCK_BROADCAST);
1630 break;
1631
1632 case SO_SNDBUF:
1633 v.val = READ_ONCE(sk->sk_sndbuf);
1634 break;
1635
1636 case SO_RCVBUF:
1637 v.val = READ_ONCE(sk->sk_rcvbuf);
1638 break;
1639
1640 case SO_REUSEADDR:
1641 v.val = sk->sk_reuse;
1642 break;
1643
1644 case SO_REUSEPORT:
1645 v.val = sk->sk_reuseport;
1646 break;
1647
1648 case SO_KEEPALIVE:
1649 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1650 break;
1651
1652 case SO_TYPE:
1653 v.val = sk->sk_type;
1654 break;
1655
1656 case SO_PROTOCOL:
1657 v.val = sk->sk_protocol;
1658 break;
1659
1660 case SO_DOMAIN:
1661 v.val = sk->sk_family;
1662 break;
1663
1664 case SO_ERROR:
1665 v.val = -sock_error(sk);
1666 if (v.val == 0)
1667 v.val = xchg(&sk->sk_err_soft, 0);
1668 break;
1669
1670 case SO_OOBINLINE:
1671 v.val = sock_flag(sk, SOCK_URGINLINE);
1672 break;
1673
1674 case SO_NO_CHECK:
1675 v.val = sk->sk_no_check_tx;
1676 break;
1677
1678 case SO_PRIORITY:
1679 v.val = READ_ONCE(sk->sk_priority);
1680 break;
1681
1682 case SO_LINGER:
1683 lv = sizeof(v.ling);
1684 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1685 v.ling.l_linger = READ_ONCE(sk->sk_lingertime) / HZ;
1686 break;
1687
1688 case SO_BSDCOMPAT:
1689 break;
1690
1691 case SO_TIMESTAMP_OLD:
1692 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1693 !sock_flag(sk, SOCK_TSTAMP_NEW) &&
1694 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1695 break;
1696
1697 case SO_TIMESTAMPNS_OLD:
1698 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1699 break;
1700
1701 case SO_TIMESTAMP_NEW:
1702 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1703 break;
1704
1705 case SO_TIMESTAMPNS_NEW:
1706 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1707 break;
1708
1709 case SO_TIMESTAMPING_OLD:
1710 case SO_TIMESTAMPING_NEW:
1711 lv = sizeof(v.timestamping);
1712 /* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1713 * returning the flags when they were set through the same option.
1714 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1715 */
1716 if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1717 v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1718 v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1719 }
1720 break;
1721
1722 case SO_RCVTIMEO_OLD:
1723 case SO_RCVTIMEO_NEW:
1724 lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1725 SO_RCVTIMEO_OLD == optname);
1726 break;
1727
1728 case SO_SNDTIMEO_OLD:
1729 case SO_SNDTIMEO_NEW:
1730 lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1731 SO_SNDTIMEO_OLD == optname);
1732 break;
1733
1734 case SO_RCVLOWAT:
1735 v.val = READ_ONCE(sk->sk_rcvlowat);
1736 break;
1737
1738 case SO_SNDLOWAT:
1739 v.val = 1;
1740 break;
1741
1742 case SO_PASSCRED:
1743 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1744 break;
1745
1746 case SO_PASSPIDFD:
1747 v.val = !!test_bit(SOCK_PASSPIDFD, &sock->flags);
1748 break;
1749
1750 case SO_PEERCRED:
1751 {
1752 struct ucred peercred;
1753 if (len > sizeof(peercred))
1754 len = sizeof(peercred);
1755
1756 spin_lock(&sk->sk_peer_lock);
1757 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1758 spin_unlock(&sk->sk_peer_lock);
1759
1760 if (copy_to_sockptr(optval, &peercred, len))
1761 return -EFAULT;
1762 goto lenout;
1763 }
1764
1765 case SO_PEERPIDFD:
1766 {
1767 struct pid *peer_pid;
1768 struct file *pidfd_file = NULL;
1769 int pidfd;
1770
1771 if (len > sizeof(pidfd))
1772 len = sizeof(pidfd);
1773
1774 spin_lock(&sk->sk_peer_lock);
1775 peer_pid = get_pid(sk->sk_peer_pid);
1776 spin_unlock(&sk->sk_peer_lock);
1777
1778 if (!peer_pid)
1779 return -ENODATA;
1780
1781 pidfd = pidfd_prepare(peer_pid, 0, &pidfd_file);
1782 put_pid(peer_pid);
1783 if (pidfd < 0)
1784 return pidfd;
1785
1786 if (copy_to_sockptr(optval, &pidfd, len) ||
1787 copy_to_sockptr(optlen, &len, sizeof(int))) {
1788 put_unused_fd(pidfd);
1789 fput(pidfd_file);
1790
1791 return -EFAULT;
1792 }
1793
1794 fd_install(pidfd, pidfd_file);
1795 return 0;
1796 }
1797
1798 case SO_PEERGROUPS:
1799 {
1800 const struct cred *cred;
1801 int ret, n;
1802
1803 cred = sk_get_peer_cred(sk);
1804 if (!cred)
1805 return -ENODATA;
1806
1807 n = cred->group_info->ngroups;
1808 if (len < n * sizeof(gid_t)) {
1809 len = n * sizeof(gid_t);
1810 put_cred(cred);
1811 return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1812 }
1813 len = n * sizeof(gid_t);
1814
1815 ret = groups_to_user(optval, cred->group_info);
1816 put_cred(cred);
1817 if (ret)
1818 return ret;
1819 goto lenout;
1820 }
1821
1822 case SO_PEERNAME:
1823 {
1824 struct sockaddr_storage address;
1825
1826 lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1827 if (lv < 0)
1828 return -ENOTCONN;
1829 if (lv < len)
1830 return -EINVAL;
1831 if (copy_to_sockptr(optval, &address, len))
1832 return -EFAULT;
1833 goto lenout;
1834 }
1835
1836 /* Dubious BSD thing... Probably nobody even uses it, but
1837 * the UNIX standard wants it for whatever reason... -DaveM
1838 */
1839 case SO_ACCEPTCONN:
1840 v.val = sk->sk_state == TCP_LISTEN;
1841 break;
1842
1843 case SO_PASSSEC:
1844 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1845 break;
1846
1847 case SO_PEERSEC:
1848 return security_socket_getpeersec_stream(sock,
1849 optval, optlen, len);
1850
1851 case SO_MARK:
1852 v.val = READ_ONCE(sk->sk_mark);
1853 break;
1854
1855 case SO_RCVMARK:
1856 v.val = sock_flag(sk, SOCK_RCVMARK);
1857 break;
1858
1859 case SO_RXQ_OVFL:
1860 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1861 break;
1862
1863 case SO_WIFI_STATUS:
1864 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1865 break;
1866
1867 case SO_PEEK_OFF:
1868 if (!READ_ONCE(sock->ops)->set_peek_off)
1869 return -EOPNOTSUPP;
1870
1871 v.val = READ_ONCE(sk->sk_peek_off);
1872 break;
1873 case SO_NOFCS:
1874 v.val = sock_flag(sk, SOCK_NOFCS);
1875 break;
1876
1877 case SO_BINDTODEVICE:
1878 return sock_getbindtodevice(sk, optval, optlen, len);
1879
1880 case SO_GET_FILTER:
1881 len = sk_get_filter(sk, optval, len);
1882 if (len < 0)
1883 return len;
1884
1885 goto lenout;
1886
1887 case SO_LOCK_FILTER:
1888 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1889 break;
1890
1891 case SO_BPF_EXTENSIONS:
1892 v.val = bpf_tell_extensions();
1893 break;
1894
1895 case SO_SELECT_ERR_QUEUE:
1896 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1897 break;
1898
1899#ifdef CONFIG_NET_RX_BUSY_POLL
1900 case SO_BUSY_POLL:
1901 v.val = READ_ONCE(sk->sk_ll_usec);
1902 break;
1903 case SO_PREFER_BUSY_POLL:
1904 v.val = READ_ONCE(sk->sk_prefer_busy_poll);
1905 break;
1906#endif
1907
1908 case SO_MAX_PACING_RATE:
1909 /* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
1910 if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1911 lv = sizeof(v.ulval);
1912 v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
1913 } else {
1914 /* 32bit version */
1915 v.val = min_t(unsigned long, ~0U,
1916 READ_ONCE(sk->sk_max_pacing_rate));
1917 }
1918 break;
1919
1920 case SO_INCOMING_CPU:
1921 v.val = READ_ONCE(sk->sk_incoming_cpu);
1922 break;
1923
1924 case SO_MEMINFO:
1925 {
1926 u32 meminfo[SK_MEMINFO_VARS];
1927
1928 sk_get_meminfo(sk, meminfo);
1929
1930 len = min_t(unsigned int, len, sizeof(meminfo));
1931 if (copy_to_sockptr(optval, &meminfo, len))
1932 return -EFAULT;
1933
1934 goto lenout;
1935 }
1936
1937#ifdef CONFIG_NET_RX_BUSY_POLL
1938 case SO_INCOMING_NAPI_ID:
1939 v.val = READ_ONCE(sk->sk_napi_id);
1940
1941 /* aggregate non-NAPI IDs down to 0 */
1942 if (v.val < MIN_NAPI_ID)
1943 v.val = 0;
1944
1945 break;
1946#endif
1947
1948 case SO_COOKIE:
1949 lv = sizeof(u64);
1950 if (len < lv)
1951 return -EINVAL;
1952 v.val64 = sock_gen_cookie(sk);
1953 break;
1954
1955 case SO_ZEROCOPY:
1956 v.val = sock_flag(sk, SOCK_ZEROCOPY);
1957 break;
1958
1959 case SO_TXTIME:
1960 lv = sizeof(v.txtime);
1961 v.txtime.clockid = sk->sk_clockid;
1962 v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1963 SOF_TXTIME_DEADLINE_MODE : 0;
1964 v.txtime.flags |= sk->sk_txtime_report_errors ?
1965 SOF_TXTIME_REPORT_ERRORS : 0;
1966 break;
1967
1968 case SO_BINDTOIFINDEX:
1969 v.val = READ_ONCE(sk->sk_bound_dev_if);
1970 break;
1971
1972 case SO_NETNS_COOKIE:
1973 lv = sizeof(u64);
1974 if (len != lv)
1975 return -EINVAL;
1976 v.val64 = sock_net(sk)->net_cookie;
1977 break;
1978
1979 case SO_BUF_LOCK:
1980 v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
1981 break;
1982
1983 case SO_RESERVE_MEM:
1984 v.val = READ_ONCE(sk->sk_reserved_mem);
1985 break;
1986
1987 case SO_TXREHASH:
1988 /* Paired with WRITE_ONCE() in sk_setsockopt() */
1989 v.val = READ_ONCE(sk->sk_txrehash);
1990 break;
1991
1992 default:
1993 /* We implement the SO_SNDLOWAT etc to not be settable
1994 * (1003.1g 7).
1995 */
1996 return -ENOPROTOOPT;
1997 }
1998
1999 if (len > lv)
2000 len = lv;
2001 if (copy_to_sockptr(optval, &v, len))
2002 return -EFAULT;
2003lenout:
2004 if (copy_to_sockptr(optlen, &len, sizeof(int)))
2005 return -EFAULT;
2006 return 0;
2007}
2008
2009/*
2010 * Initialize an sk_lock.
2011 *
2012 * (We also register the sk_lock with the lock validator.)
2013 */
2014static inline void sock_lock_init(struct sock *sk)
2015{
2016 if (sk->sk_kern_sock)
2017 sock_lock_init_class_and_name(
2018 sk,
2019 af_family_kern_slock_key_strings[sk->sk_family],
2020 af_family_kern_slock_keys + sk->sk_family,
2021 af_family_kern_key_strings[sk->sk_family],
2022 af_family_kern_keys + sk->sk_family);
2023 else
2024 sock_lock_init_class_and_name(
2025 sk,
2026 af_family_slock_key_strings[sk->sk_family],
2027 af_family_slock_keys + sk->sk_family,
2028 af_family_key_strings[sk->sk_family],
2029 af_family_keys + sk->sk_family);
2030}
2031
2032/*
2033 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2034 * even temporarly, because of RCU lookups. sk_node should also be left as is.
2035 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2036 */
2037static void sock_copy(struct sock *nsk, const struct sock *osk)
2038{
2039 const struct proto *prot = READ_ONCE(osk->sk_prot);
2040#ifdef CONFIG_SECURITY_NETWORK
2041 void *sptr = nsk->sk_security;
2042#endif
2043
2044 /* If we move sk_tx_queue_mapping out of the private section,
2045 * we must check if sk_tx_queue_clear() is called after
2046 * sock_copy() in sk_clone_lock().
2047 */
2048 BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2049 offsetof(struct sock, sk_dontcopy_begin) ||
2050 offsetof(struct sock, sk_tx_queue_mapping) >=
2051 offsetof(struct sock, sk_dontcopy_end));
2052
2053 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2054
2055 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2056 prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
2057
2058#ifdef CONFIG_SECURITY_NETWORK
2059 nsk->sk_security = sptr;
2060 security_sk_clone(osk, nsk);
2061#endif
2062}
2063
2064static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2065 int family)
2066{
2067 struct sock *sk;
2068 struct kmem_cache *slab;
2069
2070 slab = prot->slab;
2071 if (slab != NULL) {
2072 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2073 if (!sk)
2074 return sk;
2075 if (want_init_on_alloc(priority))
2076 sk_prot_clear_nulls(sk, prot->obj_size);
2077 } else
2078 sk = kmalloc(prot->obj_size, priority);
2079
2080 if (sk != NULL) {
2081 if (security_sk_alloc(sk, family, priority))
2082 goto out_free;
2083
2084 if (!try_module_get(prot->owner))
2085 goto out_free_sec;
2086 }
2087
2088 return sk;
2089
2090out_free_sec:
2091 security_sk_free(sk);
2092out_free:
2093 if (slab != NULL)
2094 kmem_cache_free(slab, sk);
2095 else
2096 kfree(sk);
2097 return NULL;
2098}
2099
2100static void sk_prot_free(struct proto *prot, struct sock *sk)
2101{
2102 struct kmem_cache *slab;
2103 struct module *owner;
2104
2105 owner = prot->owner;
2106 slab = prot->slab;
2107
2108 cgroup_sk_free(&sk->sk_cgrp_data);
2109 mem_cgroup_sk_free(sk);
2110 security_sk_free(sk);
2111 if (slab != NULL)
2112 kmem_cache_free(slab, sk);
2113 else
2114 kfree(sk);
2115 module_put(owner);
2116}
2117
2118/**
2119 * sk_alloc - All socket objects are allocated here
2120 * @net: the applicable net namespace
2121 * @family: protocol family
2122 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2123 * @prot: struct proto associated with this new sock instance
2124 * @kern: is this to be a kernel socket?
2125 */
2126struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2127 struct proto *prot, int kern)
2128{
2129 struct sock *sk;
2130
2131 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2132 if (sk) {
2133 sk->sk_family = family;
2134 /*
2135 * See comment in struct sock definition to understand
2136 * why we need sk_prot_creator -acme
2137 */
2138 sk->sk_prot = sk->sk_prot_creator = prot;
2139 sk->sk_kern_sock = kern;
2140 sock_lock_init(sk);
2141 sk->sk_net_refcnt = kern ? 0 : 1;
2142 if (likely(sk->sk_net_refcnt)) {
2143 get_net_track(net, &sk->ns_tracker, priority);
2144 sock_inuse_add(net, 1);
2145 } else {
2146 __netns_tracker_alloc(net, &sk->ns_tracker,
2147 false, priority);
2148 }
2149
2150 sock_net_set(sk, net);
2151 refcount_set(&sk->sk_wmem_alloc, 1);
2152
2153 mem_cgroup_sk_alloc(sk);
2154 cgroup_sk_alloc(&sk->sk_cgrp_data);
2155 sock_update_classid(&sk->sk_cgrp_data);
2156 sock_update_netprioidx(&sk->sk_cgrp_data);
2157 sk_tx_queue_clear(sk);
2158 }
2159
2160 return sk;
2161}
2162EXPORT_SYMBOL(sk_alloc);
2163
2164/* Sockets having SOCK_RCU_FREE will call this function after one RCU
2165 * grace period. This is the case for UDP sockets and TCP listeners.
2166 */
2167static void __sk_destruct(struct rcu_head *head)
2168{
2169 struct sock *sk = container_of(head, struct sock, sk_rcu);
2170 struct sk_filter *filter;
2171
2172 if (sk->sk_destruct)
2173 sk->sk_destruct(sk);
2174
2175 filter = rcu_dereference_check(sk->sk_filter,
2176 refcount_read(&sk->sk_wmem_alloc) == 0);
2177 if (filter) {
2178 sk_filter_uncharge(sk, filter);
2179 RCU_INIT_POINTER(sk->sk_filter, NULL);
2180 }
2181
2182 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2183
2184#ifdef CONFIG_BPF_SYSCALL
2185 bpf_sk_storage_free(sk);
2186#endif
2187
2188 if (atomic_read(&sk->sk_omem_alloc))
2189 pr_debug("%s: optmem leakage (%d bytes) detected\n",
2190 __func__, atomic_read(&sk->sk_omem_alloc));
2191
2192 if (sk->sk_frag.page) {
2193 put_page(sk->sk_frag.page);
2194 sk->sk_frag.page = NULL;
2195 }
2196
2197 /* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2198 put_cred(sk->sk_peer_cred);
2199 put_pid(sk->sk_peer_pid);
2200
2201 if (likely(sk->sk_net_refcnt))
2202 put_net_track(sock_net(sk), &sk->ns_tracker);
2203 else
2204 __netns_tracker_free(sock_net(sk), &sk->ns_tracker, false);
2205
2206 sk_prot_free(sk->sk_prot_creator, sk);
2207}
2208
2209void sk_destruct(struct sock *sk)
2210{
2211 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2212
2213 if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2214 reuseport_detach_sock(sk);
2215 use_call_rcu = true;
2216 }
2217
2218 if (use_call_rcu)
2219 call_rcu(&sk->sk_rcu, __sk_destruct);
2220 else
2221 __sk_destruct(&sk->sk_rcu);
2222}
2223
2224static void __sk_free(struct sock *sk)
2225{
2226 if (likely(sk->sk_net_refcnt))
2227 sock_inuse_add(sock_net(sk), -1);
2228
2229 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2230 sock_diag_broadcast_destroy(sk);
2231 else
2232 sk_destruct(sk);
2233}
2234
2235void sk_free(struct sock *sk)
2236{
2237 /*
2238 * We subtract one from sk_wmem_alloc and can know if
2239 * some packets are still in some tx queue.
2240 * If not null, sock_wfree() will call __sk_free(sk) later
2241 */
2242 if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2243 __sk_free(sk);
2244}
2245EXPORT_SYMBOL(sk_free);
2246
2247static void sk_init_common(struct sock *sk)
2248{
2249 skb_queue_head_init(&sk->sk_receive_queue);
2250 skb_queue_head_init(&sk->sk_write_queue);
2251 skb_queue_head_init(&sk->sk_error_queue);
2252
2253 rwlock_init(&sk->sk_callback_lock);
2254 lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2255 af_rlock_keys + sk->sk_family,
2256 af_family_rlock_key_strings[sk->sk_family]);
2257 lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2258 af_wlock_keys + sk->sk_family,
2259 af_family_wlock_key_strings[sk->sk_family]);
2260 lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2261 af_elock_keys + sk->sk_family,
2262 af_family_elock_key_strings[sk->sk_family]);
2263 lockdep_set_class_and_name(&sk->sk_callback_lock,
2264 af_callback_keys + sk->sk_family,
2265 af_family_clock_key_strings[sk->sk_family]);
2266}
2267
2268/**
2269 * sk_clone_lock - clone a socket, and lock its clone
2270 * @sk: the socket to clone
2271 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2272 *
2273 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2274 */
2275struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2276{
2277 struct proto *prot = READ_ONCE(sk->sk_prot);
2278 struct sk_filter *filter;
2279 bool is_charged = true;
2280 struct sock *newsk;
2281
2282 newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2283 if (!newsk)
2284 goto out;
2285
2286 sock_copy(newsk, sk);
2287
2288 newsk->sk_prot_creator = prot;
2289
2290 /* SANITY */
2291 if (likely(newsk->sk_net_refcnt)) {
2292 get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2293 sock_inuse_add(sock_net(newsk), 1);
2294 } else {
2295 /* Kernel sockets are not elevating the struct net refcount.
2296 * Instead, use a tracker to more easily detect if a layer
2297 * is not properly dismantling its kernel sockets at netns
2298 * destroy time.
2299 */
2300 __netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2301 false, priority);
2302 }
2303 sk_node_init(&newsk->sk_node);
2304 sock_lock_init(newsk);
2305 bh_lock_sock(newsk);
2306 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
2307 newsk->sk_backlog.len = 0;
2308
2309 atomic_set(&newsk->sk_rmem_alloc, 0);
2310
2311 /* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2312 refcount_set(&newsk->sk_wmem_alloc, 1);
2313
2314 atomic_set(&newsk->sk_omem_alloc, 0);
2315 sk_init_common(newsk);
2316
2317 newsk->sk_dst_cache = NULL;
2318 newsk->sk_dst_pending_confirm = 0;
2319 newsk->sk_wmem_queued = 0;
2320 newsk->sk_forward_alloc = 0;
2321 newsk->sk_reserved_mem = 0;
2322 atomic_set(&newsk->sk_drops, 0);
2323 newsk->sk_send_head = NULL;
2324 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2325 atomic_set(&newsk->sk_zckey, 0);
2326
2327 sock_reset_flag(newsk, SOCK_DONE);
2328
2329 /* sk->sk_memcg will be populated at accept() time */
2330 newsk->sk_memcg = NULL;
2331
2332 cgroup_sk_clone(&newsk->sk_cgrp_data);
2333
2334 rcu_read_lock();
2335 filter = rcu_dereference(sk->sk_filter);
2336 if (filter != NULL)
2337 /* though it's an empty new sock, the charging may fail
2338 * if sysctl_optmem_max was changed between creation of
2339 * original socket and cloning
2340 */
2341 is_charged = sk_filter_charge(newsk, filter);
2342 RCU_INIT_POINTER(newsk->sk_filter, filter);
2343 rcu_read_unlock();
2344
2345 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2346 /* We need to make sure that we don't uncharge the new
2347 * socket if we couldn't charge it in the first place
2348 * as otherwise we uncharge the parent's filter.
2349 */
2350 if (!is_charged)
2351 RCU_INIT_POINTER(newsk->sk_filter, NULL);
2352 sk_free_unlock_clone(newsk);
2353 newsk = NULL;
2354 goto out;
2355 }
2356 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2357
2358 if (bpf_sk_storage_clone(sk, newsk)) {
2359 sk_free_unlock_clone(newsk);
2360 newsk = NULL;
2361 goto out;
2362 }
2363
2364 /* Clear sk_user_data if parent had the pointer tagged
2365 * as not suitable for copying when cloning.
2366 */
2367 if (sk_user_data_is_nocopy(newsk))
2368 newsk->sk_user_data = NULL;
2369
2370 newsk->sk_err = 0;
2371 newsk->sk_err_soft = 0;
2372 newsk->sk_priority = 0;
2373 newsk->sk_incoming_cpu = raw_smp_processor_id();
2374
2375 /* Before updating sk_refcnt, we must commit prior changes to memory
2376 * (Documentation/RCU/rculist_nulls.rst for details)
2377 */
2378 smp_wmb();
2379 refcount_set(&newsk->sk_refcnt, 2);
2380
2381 sk_set_socket(newsk, NULL);
2382 sk_tx_queue_clear(newsk);
2383 RCU_INIT_POINTER(newsk->sk_wq, NULL);
2384
2385 if (newsk->sk_prot->sockets_allocated)
2386 sk_sockets_allocated_inc(newsk);
2387
2388 if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2389 net_enable_timestamp();
2390out:
2391 return newsk;
2392}
2393EXPORT_SYMBOL_GPL(sk_clone_lock);
2394
2395void sk_free_unlock_clone(struct sock *sk)
2396{
2397 /* It is still raw copy of parent, so invalidate
2398 * destructor and make plain sk_free() */
2399 sk->sk_destruct = NULL;
2400 bh_unlock_sock(sk);
2401 sk_free(sk);
2402}
2403EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2404
2405static u32 sk_dst_gso_max_size(struct sock *sk, struct dst_entry *dst)
2406{
2407 bool is_ipv6 = false;
2408 u32 max_size;
2409
2410#if IS_ENABLED(CONFIG_IPV6)
2411 is_ipv6 = (sk->sk_family == AF_INET6 &&
2412 !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2413#endif
2414 /* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2415 max_size = is_ipv6 ? READ_ONCE(dst->dev->gso_max_size) :
2416 READ_ONCE(dst->dev->gso_ipv4_max_size);
2417 if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2418 max_size = GSO_LEGACY_MAX_SIZE;
2419
2420 return max_size - (MAX_TCP_HEADER + 1);
2421}
2422
2423void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2424{
2425 u32 max_segs = 1;
2426
2427 sk->sk_route_caps = dst->dev->features;
2428 if (sk_is_tcp(sk))
2429 sk->sk_route_caps |= NETIF_F_GSO;
2430 if (sk->sk_route_caps & NETIF_F_GSO)
2431 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2432 if (unlikely(sk->sk_gso_disabled))
2433 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2434 if (sk_can_gso(sk)) {
2435 if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2436 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2437 } else {
2438 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2439 sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dst);
2440 /* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2441 max_segs = max_t(u32, READ_ONCE(dst->dev->gso_max_segs), 1);
2442 }
2443 }
2444 sk->sk_gso_max_segs = max_segs;
2445 sk_dst_set(sk, dst);
2446}
2447EXPORT_SYMBOL_GPL(sk_setup_caps);
2448
2449/*
2450 * Simple resource managers for sockets.
2451 */
2452
2453
2454/*
2455 * Write buffer destructor automatically called from kfree_skb.
2456 */
2457void sock_wfree(struct sk_buff *skb)
2458{
2459 struct sock *sk = skb->sk;
2460 unsigned int len = skb->truesize;
2461 bool free;
2462
2463 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2464 if (sock_flag(sk, SOCK_RCU_FREE) &&
2465 sk->sk_write_space == sock_def_write_space) {
2466 rcu_read_lock();
2467 free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2468 sock_def_write_space_wfree(sk);
2469 rcu_read_unlock();
2470 if (unlikely(free))
2471 __sk_free(sk);
2472 return;
2473 }
2474
2475 /*
2476 * Keep a reference on sk_wmem_alloc, this will be released
2477 * after sk_write_space() call
2478 */
2479 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2480 sk->sk_write_space(sk);
2481 len = 1;
2482 }
2483 /*
2484 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2485 * could not do because of in-flight packets
2486 */
2487 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2488 __sk_free(sk);
2489}
2490EXPORT_SYMBOL(sock_wfree);
2491
2492/* This variant of sock_wfree() is used by TCP,
2493 * since it sets SOCK_USE_WRITE_QUEUE.
2494 */
2495void __sock_wfree(struct sk_buff *skb)
2496{
2497 struct sock *sk = skb->sk;
2498
2499 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2500 __sk_free(sk);
2501}
2502
2503void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2504{
2505 skb_orphan(skb);
2506 skb->sk = sk;
2507#ifdef CONFIG_INET
2508 if (unlikely(!sk_fullsock(sk))) {
2509 skb->destructor = sock_edemux;
2510 sock_hold(sk);
2511 return;
2512 }
2513#endif
2514 skb->destructor = sock_wfree;
2515 skb_set_hash_from_sk(skb, sk);
2516 /*
2517 * We used to take a refcount on sk, but following operation
2518 * is enough to guarantee sk_free() wont free this sock until
2519 * all in-flight packets are completed
2520 */
2521 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2522}
2523EXPORT_SYMBOL(skb_set_owner_w);
2524
2525static bool can_skb_orphan_partial(const struct sk_buff *skb)
2526{
2527#ifdef CONFIG_TLS_DEVICE
2528 /* Drivers depend on in-order delivery for crypto offload,
2529 * partial orphan breaks out-of-order-OK logic.
2530 */
2531 if (skb->decrypted)
2532 return false;
2533#endif
2534 return (skb->destructor == sock_wfree ||
2535 (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2536}
2537
2538/* This helper is used by netem, as it can hold packets in its
2539 * delay queue. We want to allow the owner socket to send more
2540 * packets, as if they were already TX completed by a typical driver.
2541 * But we also want to keep skb->sk set because some packet schedulers
2542 * rely on it (sch_fq for example).
2543 */
2544void skb_orphan_partial(struct sk_buff *skb)
2545{
2546 if (skb_is_tcp_pure_ack(skb))
2547 return;
2548
2549 if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2550 return;
2551
2552 skb_orphan(skb);
2553}
2554EXPORT_SYMBOL(skb_orphan_partial);
2555
2556/*
2557 * Read buffer destructor automatically called from kfree_skb.
2558 */
2559void sock_rfree(struct sk_buff *skb)
2560{
2561 struct sock *sk = skb->sk;
2562 unsigned int len = skb->truesize;
2563
2564 atomic_sub(len, &sk->sk_rmem_alloc);
2565 sk_mem_uncharge(sk, len);
2566}
2567EXPORT_SYMBOL(sock_rfree);
2568
2569/*
2570 * Buffer destructor for skbs that are not used directly in read or write
2571 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2572 */
2573void sock_efree(struct sk_buff *skb)
2574{
2575 sock_put(skb->sk);
2576}
2577EXPORT_SYMBOL(sock_efree);
2578
2579/* Buffer destructor for prefetch/receive path where reference count may
2580 * not be held, e.g. for listen sockets.
2581 */
2582#ifdef CONFIG_INET
2583void sock_pfree(struct sk_buff *skb)
2584{
2585 if (sk_is_refcounted(skb->sk))
2586 sock_gen_put(skb->sk);
2587}
2588EXPORT_SYMBOL(sock_pfree);
2589#endif /* CONFIG_INET */
2590
2591kuid_t sock_i_uid(struct sock *sk)
2592{
2593 kuid_t uid;
2594
2595 read_lock_bh(&sk->sk_callback_lock);
2596 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2597 read_unlock_bh(&sk->sk_callback_lock);
2598 return uid;
2599}
2600EXPORT_SYMBOL(sock_i_uid);
2601
2602unsigned long __sock_i_ino(struct sock *sk)
2603{
2604 unsigned long ino;
2605
2606 read_lock(&sk->sk_callback_lock);
2607 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2608 read_unlock(&sk->sk_callback_lock);
2609 return ino;
2610}
2611EXPORT_SYMBOL(__sock_i_ino);
2612
2613unsigned long sock_i_ino(struct sock *sk)
2614{
2615 unsigned long ino;
2616
2617 local_bh_disable();
2618 ino = __sock_i_ino(sk);
2619 local_bh_enable();
2620 return ino;
2621}
2622EXPORT_SYMBOL(sock_i_ino);
2623
2624/*
2625 * Allocate a skb from the socket's send buffer.
2626 */
2627struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2628 gfp_t priority)
2629{
2630 if (force ||
2631 refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2632 struct sk_buff *skb = alloc_skb(size, priority);
2633
2634 if (skb) {
2635 skb_set_owner_w(skb, sk);
2636 return skb;
2637 }
2638 }
2639 return NULL;
2640}
2641EXPORT_SYMBOL(sock_wmalloc);
2642
2643static void sock_ofree(struct sk_buff *skb)
2644{
2645 struct sock *sk = skb->sk;
2646
2647 atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2648}
2649
2650struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2651 gfp_t priority)
2652{
2653 struct sk_buff *skb;
2654
2655 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2656 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2657 READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2658 return NULL;
2659
2660 skb = alloc_skb(size, priority);
2661 if (!skb)
2662 return NULL;
2663
2664 atomic_add(skb->truesize, &sk->sk_omem_alloc);
2665 skb->sk = sk;
2666 skb->destructor = sock_ofree;
2667 return skb;
2668}
2669
2670/*
2671 * Allocate a memory block from the socket's option memory buffer.
2672 */
2673void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2674{
2675 int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2676
2677 if ((unsigned int)size <= optmem_max &&
2678 atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2679 void *mem;
2680 /* First do the add, to avoid the race if kmalloc
2681 * might sleep.
2682 */
2683 atomic_add(size, &sk->sk_omem_alloc);
2684 mem = kmalloc(size, priority);
2685 if (mem)
2686 return mem;
2687 atomic_sub(size, &sk->sk_omem_alloc);
2688 }
2689 return NULL;
2690}
2691EXPORT_SYMBOL(sock_kmalloc);
2692
2693/* Free an option memory block. Note, we actually want the inline
2694 * here as this allows gcc to detect the nullify and fold away the
2695 * condition entirely.
2696 */
2697static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2698 const bool nullify)
2699{
2700 if (WARN_ON_ONCE(!mem))
2701 return;
2702 if (nullify)
2703 kfree_sensitive(mem);
2704 else
2705 kfree(mem);
2706 atomic_sub(size, &sk->sk_omem_alloc);
2707}
2708
2709void sock_kfree_s(struct sock *sk, void *mem, int size)
2710{
2711 __sock_kfree_s(sk, mem, size, false);
2712}
2713EXPORT_SYMBOL(sock_kfree_s);
2714
2715void sock_kzfree_s(struct sock *sk, void *mem, int size)
2716{
2717 __sock_kfree_s(sk, mem, size, true);
2718}
2719EXPORT_SYMBOL(sock_kzfree_s);
2720
2721/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2722 I think, these locks should be removed for datagram sockets.
2723 */
2724static long sock_wait_for_wmem(struct sock *sk, long timeo)
2725{
2726 DEFINE_WAIT(wait);
2727
2728 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2729 for (;;) {
2730 if (!timeo)
2731 break;
2732 if (signal_pending(current))
2733 break;
2734 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2735 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2736 if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2737 break;
2738 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2739 break;
2740 if (READ_ONCE(sk->sk_err))
2741 break;
2742 timeo = schedule_timeout(timeo);
2743 }
2744 finish_wait(sk_sleep(sk), &wait);
2745 return timeo;
2746}
2747
2748
2749/*
2750 * Generic send/receive buffer handlers
2751 */
2752
2753struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2754 unsigned long data_len, int noblock,
2755 int *errcode, int max_page_order)
2756{
2757 struct sk_buff *skb;
2758 long timeo;
2759 int err;
2760
2761 timeo = sock_sndtimeo(sk, noblock);
2762 for (;;) {
2763 err = sock_error(sk);
2764 if (err != 0)
2765 goto failure;
2766
2767 err = -EPIPE;
2768 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2769 goto failure;
2770
2771 if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2772 break;
2773
2774 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2775 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2776 err = -EAGAIN;
2777 if (!timeo)
2778 goto failure;
2779 if (signal_pending(current))
2780 goto interrupted;
2781 timeo = sock_wait_for_wmem(sk, timeo);
2782 }
2783 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2784 errcode, sk->sk_allocation);
2785 if (skb)
2786 skb_set_owner_w(skb, sk);
2787 return skb;
2788
2789interrupted:
2790 err = sock_intr_errno(timeo);
2791failure:
2792 *errcode = err;
2793 return NULL;
2794}
2795EXPORT_SYMBOL(sock_alloc_send_pskb);
2796
2797int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2798 struct sockcm_cookie *sockc)
2799{
2800 u32 tsflags;
2801
2802 switch (cmsg->cmsg_type) {
2803 case SO_MARK:
2804 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2805 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2806 return -EPERM;
2807 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2808 return -EINVAL;
2809 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2810 break;
2811 case SO_TIMESTAMPING_OLD:
2812 case SO_TIMESTAMPING_NEW:
2813 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2814 return -EINVAL;
2815
2816 tsflags = *(u32 *)CMSG_DATA(cmsg);
2817 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2818 return -EINVAL;
2819
2820 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2821 sockc->tsflags |= tsflags;
2822 break;
2823 case SCM_TXTIME:
2824 if (!sock_flag(sk, SOCK_TXTIME))
2825 return -EINVAL;
2826 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2827 return -EINVAL;
2828 sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2829 break;
2830 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2831 case SCM_RIGHTS:
2832 case SCM_CREDENTIALS:
2833 break;
2834 default:
2835 return -EINVAL;
2836 }
2837 return 0;
2838}
2839EXPORT_SYMBOL(__sock_cmsg_send);
2840
2841int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2842 struct sockcm_cookie *sockc)
2843{
2844 struct cmsghdr *cmsg;
2845 int ret;
2846
2847 for_each_cmsghdr(cmsg, msg) {
2848 if (!CMSG_OK(msg, cmsg))
2849 return -EINVAL;
2850 if (cmsg->cmsg_level != SOL_SOCKET)
2851 continue;
2852 ret = __sock_cmsg_send(sk, cmsg, sockc);
2853 if (ret)
2854 return ret;
2855 }
2856 return 0;
2857}
2858EXPORT_SYMBOL(sock_cmsg_send);
2859
2860static void sk_enter_memory_pressure(struct sock *sk)
2861{
2862 if (!sk->sk_prot->enter_memory_pressure)
2863 return;
2864
2865 sk->sk_prot->enter_memory_pressure(sk);
2866}
2867
2868static void sk_leave_memory_pressure(struct sock *sk)
2869{
2870 if (sk->sk_prot->leave_memory_pressure) {
2871 INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
2872 tcp_leave_memory_pressure, sk);
2873 } else {
2874 unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2875
2876 if (memory_pressure && READ_ONCE(*memory_pressure))
2877 WRITE_ONCE(*memory_pressure, 0);
2878 }
2879}
2880
2881DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2882
2883/**
2884 * skb_page_frag_refill - check that a page_frag contains enough room
2885 * @sz: minimum size of the fragment we want to get
2886 * @pfrag: pointer to page_frag
2887 * @gfp: priority for memory allocation
2888 *
2889 * Note: While this allocator tries to use high order pages, there is
2890 * no guarantee that allocations succeed. Therefore, @sz MUST be
2891 * less or equal than PAGE_SIZE.
2892 */
2893bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2894{
2895 if (pfrag->page) {
2896 if (page_ref_count(pfrag->page) == 1) {
2897 pfrag->offset = 0;
2898 return true;
2899 }
2900 if (pfrag->offset + sz <= pfrag->size)
2901 return true;
2902 put_page(pfrag->page);
2903 }
2904
2905 pfrag->offset = 0;
2906 if (SKB_FRAG_PAGE_ORDER &&
2907 !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2908 /* Avoid direct reclaim but allow kswapd to wake */
2909 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2910 __GFP_COMP | __GFP_NOWARN |
2911 __GFP_NORETRY,
2912 SKB_FRAG_PAGE_ORDER);
2913 if (likely(pfrag->page)) {
2914 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2915 return true;
2916 }
2917 }
2918 pfrag->page = alloc_page(gfp);
2919 if (likely(pfrag->page)) {
2920 pfrag->size = PAGE_SIZE;
2921 return true;
2922 }
2923 return false;
2924}
2925EXPORT_SYMBOL(skb_page_frag_refill);
2926
2927bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2928{
2929 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2930 return true;
2931
2932 sk_enter_memory_pressure(sk);
2933 sk_stream_moderate_sndbuf(sk);
2934 return false;
2935}
2936EXPORT_SYMBOL(sk_page_frag_refill);
2937
2938void __lock_sock(struct sock *sk)
2939 __releases(&sk->sk_lock.slock)
2940 __acquires(&sk->sk_lock.slock)
2941{
2942 DEFINE_WAIT(wait);
2943
2944 for (;;) {
2945 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2946 TASK_UNINTERRUPTIBLE);
2947 spin_unlock_bh(&sk->sk_lock.slock);
2948 schedule();
2949 spin_lock_bh(&sk->sk_lock.slock);
2950 if (!sock_owned_by_user(sk))
2951 break;
2952 }
2953 finish_wait(&sk->sk_lock.wq, &wait);
2954}
2955
2956void __release_sock(struct sock *sk)
2957 __releases(&sk->sk_lock.slock)
2958 __acquires(&sk->sk_lock.slock)
2959{
2960 struct sk_buff *skb, *next;
2961
2962 while ((skb = sk->sk_backlog.head) != NULL) {
2963 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2964
2965 spin_unlock_bh(&sk->sk_lock.slock);
2966
2967 do {
2968 next = skb->next;
2969 prefetch(next);
2970 DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
2971 skb_mark_not_on_list(skb);
2972 sk_backlog_rcv(sk, skb);
2973
2974 cond_resched();
2975
2976 skb = next;
2977 } while (skb != NULL);
2978
2979 spin_lock_bh(&sk->sk_lock.slock);
2980 }
2981
2982 /*
2983 * Doing the zeroing here guarantee we can not loop forever
2984 * while a wild producer attempts to flood us.
2985 */
2986 sk->sk_backlog.len = 0;
2987}
2988
2989void __sk_flush_backlog(struct sock *sk)
2990{
2991 spin_lock_bh(&sk->sk_lock.slock);
2992 __release_sock(sk);
2993
2994 if (sk->sk_prot->release_cb)
2995 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
2996 tcp_release_cb, sk);
2997
2998 spin_unlock_bh(&sk->sk_lock.slock);
2999}
3000EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3001
3002/**
3003 * sk_wait_data - wait for data to arrive at sk_receive_queue
3004 * @sk: sock to wait on
3005 * @timeo: for how long
3006 * @skb: last skb seen on sk_receive_queue
3007 *
3008 * Now socket state including sk->sk_err is changed only under lock,
3009 * hence we may omit checks after joining wait queue.
3010 * We check receive queue before schedule() only as optimization;
3011 * it is very likely that release_sock() added new data.
3012 */
3013int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3014{
3015 DEFINE_WAIT_FUNC(wait, woken_wake_function);
3016 int rc;
3017
3018 add_wait_queue(sk_sleep(sk), &wait);
3019 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3020 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3021 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3022 remove_wait_queue(sk_sleep(sk), &wait);
3023 return rc;
3024}
3025EXPORT_SYMBOL(sk_wait_data);
3026
3027/**
3028 * __sk_mem_raise_allocated - increase memory_allocated
3029 * @sk: socket
3030 * @size: memory size to allocate
3031 * @amt: pages to allocate
3032 * @kind: allocation type
3033 *
3034 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3035 *
3036 * Unlike the globally shared limits among the sockets under same protocol,
3037 * consuming the budget of a memcg won't have direct effect on other ones.
3038 * So be optimistic about memcg's tolerance, and leave the callers to decide
3039 * whether or not to raise allocated through sk_under_memory_pressure() or
3040 * its variants.
3041 */
3042int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3043{
3044 struct mem_cgroup *memcg = mem_cgroup_sockets_enabled ? sk->sk_memcg : NULL;
3045 struct proto *prot = sk->sk_prot;
3046 bool charged = false;
3047 long allocated;
3048
3049 sk_memory_allocated_add(sk, amt);
3050 allocated = sk_memory_allocated(sk);
3051
3052 if (memcg) {
3053 if (!mem_cgroup_charge_skmem(memcg, amt, gfp_memcg_charge()))
3054 goto suppress_allocation;
3055 charged = true;
3056 }
3057
3058 /* Under limit. */
3059 if (allocated <= sk_prot_mem_limits(sk, 0)) {
3060 sk_leave_memory_pressure(sk);
3061 return 1;
3062 }
3063
3064 /* Under pressure. */
3065 if (allocated > sk_prot_mem_limits(sk, 1))
3066 sk_enter_memory_pressure(sk);
3067
3068 /* Over hard limit. */
3069 if (allocated > sk_prot_mem_limits(sk, 2))
3070 goto suppress_allocation;
3071
3072 /* Guarantee minimum buffer size under pressure (either global
3073 * or memcg) to make sure features described in RFC 7323 (TCP
3074 * Extensions for High Performance) work properly.
3075 *
3076 * This rule does NOT stand when exceeds global or memcg's hard
3077 * limit, or else a DoS attack can be taken place by spawning
3078 * lots of sockets whose usage are under minimum buffer size.
3079 */
3080 if (kind == SK_MEM_RECV) {
3081 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3082 return 1;
3083
3084 } else { /* SK_MEM_SEND */
3085 int wmem0 = sk_get_wmem0(sk, prot);
3086
3087 if (sk->sk_type == SOCK_STREAM) {
3088 if (sk->sk_wmem_queued < wmem0)
3089 return 1;
3090 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3091 return 1;
3092 }
3093 }
3094
3095 if (sk_has_memory_pressure(sk)) {
3096 u64 alloc;
3097
3098 /* The following 'average' heuristic is within the
3099 * scope of global accounting, so it only makes
3100 * sense for global memory pressure.
3101 */
3102 if (!sk_under_global_memory_pressure(sk))
3103 return 1;
3104
3105 /* Try to be fair among all the sockets under global
3106 * pressure by allowing the ones that below average
3107 * usage to raise.
3108 */
3109 alloc = sk_sockets_allocated_read_positive(sk);
3110 if (sk_prot_mem_limits(sk, 2) > alloc *
3111 sk_mem_pages(sk->sk_wmem_queued +
3112 atomic_read(&sk->sk_rmem_alloc) +
3113 sk->sk_forward_alloc))
3114 return 1;
3115 }
3116
3117suppress_allocation:
3118
3119 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3120 sk_stream_moderate_sndbuf(sk);
3121
3122 /* Fail only if socket is _under_ its sndbuf.
3123 * In this case we cannot block, so that we have to fail.
3124 */
3125 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3126 /* Force charge with __GFP_NOFAIL */
3127 if (memcg && !charged) {
3128 mem_cgroup_charge_skmem(memcg, amt,
3129 gfp_memcg_charge() | __GFP_NOFAIL);
3130 }
3131 return 1;
3132 }
3133 }
3134
3135 if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
3136 trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3137
3138 sk_memory_allocated_sub(sk, amt);
3139
3140 if (charged)
3141 mem_cgroup_uncharge_skmem(memcg, amt);
3142
3143 return 0;
3144}
3145
3146/**
3147 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3148 * @sk: socket
3149 * @size: memory size to allocate
3150 * @kind: allocation type
3151 *
3152 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3153 * rmem allocation. This function assumes that protocols which have
3154 * memory_pressure use sk_wmem_queued as write buffer accounting.
3155 */
3156int __sk_mem_schedule(struct sock *sk, int size, int kind)
3157{
3158 int ret, amt = sk_mem_pages(size);
3159
3160 sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3161 ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3162 if (!ret)
3163 sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3164 return ret;
3165}
3166EXPORT_SYMBOL(__sk_mem_schedule);
3167
3168/**
3169 * __sk_mem_reduce_allocated - reclaim memory_allocated
3170 * @sk: socket
3171 * @amount: number of quanta
3172 *
3173 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3174 */
3175void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3176{
3177 sk_memory_allocated_sub(sk, amount);
3178
3179 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
3180 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
3181
3182 if (sk_under_global_memory_pressure(sk) &&
3183 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3184 sk_leave_memory_pressure(sk);
3185}
3186
3187/**
3188 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3189 * @sk: socket
3190 * @amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3191 */
3192void __sk_mem_reclaim(struct sock *sk, int amount)
3193{
3194 amount >>= PAGE_SHIFT;
3195 sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3196 __sk_mem_reduce_allocated(sk, amount);
3197}
3198EXPORT_SYMBOL(__sk_mem_reclaim);
3199
3200int sk_set_peek_off(struct sock *sk, int val)
3201{
3202 WRITE_ONCE(sk->sk_peek_off, val);
3203 return 0;
3204}
3205EXPORT_SYMBOL_GPL(sk_set_peek_off);
3206
3207/*
3208 * Set of default routines for initialising struct proto_ops when
3209 * the protocol does not support a particular function. In certain
3210 * cases where it makes no sense for a protocol to have a "do nothing"
3211 * function, some default processing is provided.
3212 */
3213
3214int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3215{
3216 return -EOPNOTSUPP;
3217}
3218EXPORT_SYMBOL(sock_no_bind);
3219
3220int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3221 int len, int flags)
3222{
3223 return -EOPNOTSUPP;
3224}
3225EXPORT_SYMBOL(sock_no_connect);
3226
3227int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3228{
3229 return -EOPNOTSUPP;
3230}
3231EXPORT_SYMBOL(sock_no_socketpair);
3232
3233int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
3234 bool kern)
3235{
3236 return -EOPNOTSUPP;
3237}
3238EXPORT_SYMBOL(sock_no_accept);
3239
3240int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3241 int peer)
3242{
3243 return -EOPNOTSUPP;
3244}
3245EXPORT_SYMBOL(sock_no_getname);
3246
3247int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3248{
3249 return -EOPNOTSUPP;
3250}
3251EXPORT_SYMBOL(sock_no_ioctl);
3252
3253int sock_no_listen(struct socket *sock, int backlog)
3254{
3255 return -EOPNOTSUPP;
3256}
3257EXPORT_SYMBOL(sock_no_listen);
3258
3259int sock_no_shutdown(struct socket *sock, int how)
3260{
3261 return -EOPNOTSUPP;
3262}
3263EXPORT_SYMBOL(sock_no_shutdown);
3264
3265int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3266{
3267 return -EOPNOTSUPP;
3268}
3269EXPORT_SYMBOL(sock_no_sendmsg);
3270
3271int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3272{
3273 return -EOPNOTSUPP;
3274}
3275EXPORT_SYMBOL(sock_no_sendmsg_locked);
3276
3277int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3278 int flags)
3279{
3280 return -EOPNOTSUPP;
3281}
3282EXPORT_SYMBOL(sock_no_recvmsg);
3283
3284int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3285{
3286 /* Mirror missing mmap method error code */
3287 return -ENODEV;
3288}
3289EXPORT_SYMBOL(sock_no_mmap);
3290
3291/*
3292 * When a file is received (via SCM_RIGHTS, etc), we must bump the
3293 * various sock-based usage counts.
3294 */
3295void __receive_sock(struct file *file)
3296{
3297 struct socket *sock;
3298
3299 sock = sock_from_file(file);
3300 if (sock) {
3301 sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3302 sock_update_classid(&sock->sk->sk_cgrp_data);
3303 }
3304}
3305
3306/*
3307 * Default Socket Callbacks
3308 */
3309
3310static void sock_def_wakeup(struct sock *sk)
3311{
3312 struct socket_wq *wq;
3313
3314 rcu_read_lock();
3315 wq = rcu_dereference(sk->sk_wq);
3316 if (skwq_has_sleeper(wq))
3317 wake_up_interruptible_all(&wq->wait);
3318 rcu_read_unlock();
3319}
3320
3321static void sock_def_error_report(struct sock *sk)
3322{
3323 struct socket_wq *wq;
3324
3325 rcu_read_lock();
3326 wq = rcu_dereference(sk->sk_wq);
3327 if (skwq_has_sleeper(wq))
3328 wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3329 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
3330 rcu_read_unlock();
3331}
3332
3333void sock_def_readable(struct sock *sk)
3334{
3335 struct socket_wq *wq;
3336
3337 trace_sk_data_ready(sk);
3338
3339 rcu_read_lock();
3340 wq = rcu_dereference(sk->sk_wq);
3341 if (skwq_has_sleeper(wq))
3342 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3343 EPOLLRDNORM | EPOLLRDBAND);
3344 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
3345 rcu_read_unlock();
3346}
3347
3348static void sock_def_write_space(struct sock *sk)
3349{
3350 struct socket_wq *wq;
3351
3352 rcu_read_lock();
3353
3354 /* Do not wake up a writer until he can make "significant"
3355 * progress. --DaveM
3356 */
3357 if (sock_writeable(sk)) {
3358 wq = rcu_dereference(sk->sk_wq);
3359 if (skwq_has_sleeper(wq))
3360 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3361 EPOLLWRNORM | EPOLLWRBAND);
3362
3363 /* Should agree with poll, otherwise some programs break */
3364 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3365 }
3366
3367 rcu_read_unlock();
3368}
3369
3370/* An optimised version of sock_def_write_space(), should only be called
3371 * for SOCK_RCU_FREE sockets under RCU read section and after putting
3372 * ->sk_wmem_alloc.
3373 */
3374static void sock_def_write_space_wfree(struct sock *sk)
3375{
3376 /* Do not wake up a writer until he can make "significant"
3377 * progress. --DaveM
3378 */
3379 if (sock_writeable(sk)) {
3380 struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3381
3382 /* rely on refcount_sub from sock_wfree() */
3383 smp_mb__after_atomic();
3384 if (wq && waitqueue_active(&wq->wait))
3385 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3386 EPOLLWRNORM | EPOLLWRBAND);
3387
3388 /* Should agree with poll, otherwise some programs break */
3389 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
3390 }
3391}
3392
3393static void sock_def_destruct(struct sock *sk)
3394{
3395}
3396
3397void sk_send_sigurg(struct sock *sk)
3398{
3399 if (sk->sk_socket && sk->sk_socket->file)
3400 if (send_sigurg(&sk->sk_socket->file->f_owner))
3401 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3402}
3403EXPORT_SYMBOL(sk_send_sigurg);
3404
3405void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3406 unsigned long expires)
3407{
3408 if (!mod_timer(timer, expires))
3409 sock_hold(sk);
3410}
3411EXPORT_SYMBOL(sk_reset_timer);
3412
3413void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3414{
3415 if (del_timer(timer))
3416 __sock_put(sk);
3417}
3418EXPORT_SYMBOL(sk_stop_timer);
3419
3420void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3421{
3422 if (del_timer_sync(timer))
3423 __sock_put(sk);
3424}
3425EXPORT_SYMBOL(sk_stop_timer_sync);
3426
3427void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3428{
3429 sk_init_common(sk);
3430 sk->sk_send_head = NULL;
3431
3432 timer_setup(&sk->sk_timer, NULL, 0);
3433
3434 sk->sk_allocation = GFP_KERNEL;
3435 sk->sk_rcvbuf = READ_ONCE(sysctl_rmem_default);
3436 sk->sk_sndbuf = READ_ONCE(sysctl_wmem_default);
3437 sk->sk_state = TCP_CLOSE;
3438 sk->sk_use_task_frag = true;
3439 sk_set_socket(sk, sock);
3440
3441 sock_set_flag(sk, SOCK_ZAPPED);
3442
3443 if (sock) {
3444 sk->sk_type = sock->type;
3445 RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3446 sock->sk = sk;
3447 } else {
3448 RCU_INIT_POINTER(sk->sk_wq, NULL);
3449 }
3450 sk->sk_uid = uid;
3451
3452 rwlock_init(&sk->sk_callback_lock);
3453 if (sk->sk_kern_sock)
3454 lockdep_set_class_and_name(
3455 &sk->sk_callback_lock,
3456 af_kern_callback_keys + sk->sk_family,
3457 af_family_kern_clock_key_strings[sk->sk_family]);
3458 else
3459 lockdep_set_class_and_name(
3460 &sk->sk_callback_lock,
3461 af_callback_keys + sk->sk_family,
3462 af_family_clock_key_strings[sk->sk_family]);
3463
3464 sk->sk_state_change = sock_def_wakeup;
3465 sk->sk_data_ready = sock_def_readable;
3466 sk->sk_write_space = sock_def_write_space;
3467 sk->sk_error_report = sock_def_error_report;
3468 sk->sk_destruct = sock_def_destruct;
3469
3470 sk->sk_frag.page = NULL;
3471 sk->sk_frag.offset = 0;
3472 sk->sk_peek_off = -1;
3473
3474 sk->sk_peer_pid = NULL;
3475 sk->sk_peer_cred = NULL;
3476 spin_lock_init(&sk->sk_peer_lock);
3477
3478 sk->sk_write_pending = 0;
3479 sk->sk_rcvlowat = 1;
3480 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
3481 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
3482
3483 sk->sk_stamp = SK_DEFAULT_STAMP;
3484#if BITS_PER_LONG==32
3485 seqlock_init(&sk->sk_stamp_seq);
3486#endif
3487 atomic_set(&sk->sk_zckey, 0);
3488
3489#ifdef CONFIG_NET_RX_BUSY_POLL
3490 sk->sk_napi_id = 0;
3491 sk->sk_ll_usec = READ_ONCE(sysctl_net_busy_read);
3492#endif
3493
3494 sk->sk_max_pacing_rate = ~0UL;
3495 sk->sk_pacing_rate = ~0UL;
3496 WRITE_ONCE(sk->sk_pacing_shift, 10);
3497 sk->sk_incoming_cpu = -1;
3498
3499 sk_rx_queue_clear(sk);
3500 /*
3501 * Before updating sk_refcnt, we must commit prior changes to memory
3502 * (Documentation/RCU/rculist_nulls.rst for details)
3503 */
3504 smp_wmb();
3505 refcount_set(&sk->sk_refcnt, 1);
3506 atomic_set(&sk->sk_drops, 0);
3507}
3508EXPORT_SYMBOL(sock_init_data_uid);
3509
3510void sock_init_data(struct socket *sock, struct sock *sk)
3511{
3512 kuid_t uid = sock ?
3513 SOCK_INODE(sock)->i_uid :
3514 make_kuid(sock_net(sk)->user_ns, 0);
3515
3516 sock_init_data_uid(sock, sk, uid);
3517}
3518EXPORT_SYMBOL(sock_init_data);
3519
3520void lock_sock_nested(struct sock *sk, int subclass)
3521{
3522 /* The sk_lock has mutex_lock() semantics here. */
3523 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3524
3525 might_sleep();
3526 spin_lock_bh(&sk->sk_lock.slock);
3527 if (sock_owned_by_user_nocheck(sk))
3528 __lock_sock(sk);
3529 sk->sk_lock.owned = 1;
3530 spin_unlock_bh(&sk->sk_lock.slock);
3531}
3532EXPORT_SYMBOL(lock_sock_nested);
3533
3534void release_sock(struct sock *sk)
3535{
3536 spin_lock_bh(&sk->sk_lock.slock);
3537 if (sk->sk_backlog.tail)
3538 __release_sock(sk);
3539
3540 if (sk->sk_prot->release_cb)
3541 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3542 tcp_release_cb, sk);
3543
3544 sock_release_ownership(sk);
3545 if (waitqueue_active(&sk->sk_lock.wq))
3546 wake_up(&sk->sk_lock.wq);
3547 spin_unlock_bh(&sk->sk_lock.slock);
3548}
3549EXPORT_SYMBOL(release_sock);
3550
3551bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3552{
3553 might_sleep();
3554 spin_lock_bh(&sk->sk_lock.slock);
3555
3556 if (!sock_owned_by_user_nocheck(sk)) {
3557 /*
3558 * Fast path return with bottom halves disabled and
3559 * sock::sk_lock.slock held.
3560 *
3561 * The 'mutex' is not contended and holding
3562 * sock::sk_lock.slock prevents all other lockers to
3563 * proceed so the corresponding unlock_sock_fast() can
3564 * avoid the slow path of release_sock() completely and
3565 * just release slock.
3566 *
3567 * From a semantical POV this is equivalent to 'acquiring'
3568 * the 'mutex', hence the corresponding lockdep
3569 * mutex_release() has to happen in the fast path of
3570 * unlock_sock_fast().
3571 */
3572 return false;
3573 }
3574
3575 __lock_sock(sk);
3576 sk->sk_lock.owned = 1;
3577 __acquire(&sk->sk_lock.slock);
3578 spin_unlock_bh(&sk->sk_lock.slock);
3579 return true;
3580}
3581EXPORT_SYMBOL(__lock_sock_fast);
3582
3583int sock_gettstamp(struct socket *sock, void __user *userstamp,
3584 bool timeval, bool time32)
3585{
3586 struct sock *sk = sock->sk;
3587 struct timespec64 ts;
3588
3589 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3590 ts = ktime_to_timespec64(sock_read_timestamp(sk));
3591 if (ts.tv_sec == -1)
3592 return -ENOENT;
3593 if (ts.tv_sec == 0) {
3594 ktime_t kt = ktime_get_real();
3595 sock_write_timestamp(sk, kt);
3596 ts = ktime_to_timespec64(kt);
3597 }
3598
3599 if (timeval)
3600 ts.tv_nsec /= 1000;
3601
3602#ifdef CONFIG_COMPAT_32BIT_TIME
3603 if (time32)
3604 return put_old_timespec32(&ts, userstamp);
3605#endif
3606#ifdef CONFIG_SPARC64
3607 /* beware of padding in sparc64 timeval */
3608 if (timeval && !in_compat_syscall()) {
3609 struct __kernel_old_timeval __user tv = {
3610 .tv_sec = ts.tv_sec,
3611 .tv_usec = ts.tv_nsec,
3612 };
3613 if (copy_to_user(userstamp, &tv, sizeof(tv)))
3614 return -EFAULT;
3615 return 0;
3616 }
3617#endif
3618 return put_timespec64(&ts, userstamp);
3619}
3620EXPORT_SYMBOL(sock_gettstamp);
3621
3622void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3623{
3624 if (!sock_flag(sk, flag)) {
3625 unsigned long previous_flags = sk->sk_flags;
3626
3627 sock_set_flag(sk, flag);
3628 /*
3629 * we just set one of the two flags which require net
3630 * time stamping, but time stamping might have been on
3631 * already because of the other one
3632 */
3633 if (sock_needs_netstamp(sk) &&
3634 !(previous_flags & SK_FLAGS_TIMESTAMP))
3635 net_enable_timestamp();
3636 }
3637}
3638
3639int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3640 int level, int type)
3641{
3642 struct sock_exterr_skb *serr;
3643 struct sk_buff *skb;
3644 int copied, err;
3645
3646 err = -EAGAIN;
3647 skb = sock_dequeue_err_skb(sk);
3648 if (skb == NULL)
3649 goto out;
3650
3651 copied = skb->len;
3652 if (copied > len) {
3653 msg->msg_flags |= MSG_TRUNC;
3654 copied = len;
3655 }
3656 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3657 if (err)
3658 goto out_free_skb;
3659
3660 sock_recv_timestamp(msg, sk, skb);
3661
3662 serr = SKB_EXT_ERR(skb);
3663 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3664
3665 msg->msg_flags |= MSG_ERRQUEUE;
3666 err = copied;
3667
3668out_free_skb:
3669 kfree_skb(skb);
3670out:
3671 return err;
3672}
3673EXPORT_SYMBOL(sock_recv_errqueue);
3674
3675/*
3676 * Get a socket option on an socket.
3677 *
3678 * FIX: POSIX 1003.1g is very ambiguous here. It states that
3679 * asynchronous errors should be reported by getsockopt. We assume
3680 * this means if you specify SO_ERROR (otherwise whats the point of it).
3681 */
3682int sock_common_getsockopt(struct socket *sock, int level, int optname,
3683 char __user *optval, int __user *optlen)
3684{
3685 struct sock *sk = sock->sk;
3686
3687 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
3688 return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3689}
3690EXPORT_SYMBOL(sock_common_getsockopt);
3691
3692int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3693 int flags)
3694{
3695 struct sock *sk = sock->sk;
3696 int addr_len = 0;
3697 int err;
3698
3699 err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3700 if (err >= 0)
3701 msg->msg_namelen = addr_len;
3702 return err;
3703}
3704EXPORT_SYMBOL(sock_common_recvmsg);
3705
3706/*
3707 * Set socket options on an inet socket.
3708 */
3709int sock_common_setsockopt(struct socket *sock, int level, int optname,
3710 sockptr_t optval, unsigned int optlen)
3711{
3712 struct sock *sk = sock->sk;
3713
3714 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
3715 return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3716}
3717EXPORT_SYMBOL(sock_common_setsockopt);
3718
3719void sk_common_release(struct sock *sk)
3720{
3721 if (sk->sk_prot->destroy)
3722 sk->sk_prot->destroy(sk);
3723
3724 /*
3725 * Observation: when sk_common_release is called, processes have
3726 * no access to socket. But net still has.
3727 * Step one, detach it from networking:
3728 *
3729 * A. Remove from hash tables.
3730 */
3731
3732 sk->sk_prot->unhash(sk);
3733
3734 /*
3735 * In this point socket cannot receive new packets, but it is possible
3736 * that some packets are in flight because some CPU runs receiver and
3737 * did hash table lookup before we unhashed socket. They will achieve
3738 * receive queue and will be purged by socket destructor.
3739 *
3740 * Also we still have packets pending on receive queue and probably,
3741 * our own packets waiting in device queues. sock_destroy will drain
3742 * receive queue, but transmitted packets will delay socket destruction
3743 * until the last reference will be released.
3744 */
3745
3746 sock_orphan(sk);
3747
3748 xfrm_sk_free_policy(sk);
3749
3750 sock_put(sk);
3751}
3752EXPORT_SYMBOL(sk_common_release);
3753
3754void sk_get_meminfo(const struct sock *sk, u32 *mem)
3755{
3756 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3757
3758 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3759 mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3760 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3761 mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3762 mem[SK_MEMINFO_FWD_ALLOC] = sk_forward_alloc_get(sk);
3763 mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3764 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3765 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3766 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3767}
3768
3769#ifdef CONFIG_PROC_FS
3770static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3771
3772int sock_prot_inuse_get(struct net *net, struct proto *prot)
3773{
3774 int cpu, idx = prot->inuse_idx;
3775 int res = 0;
3776
3777 for_each_possible_cpu(cpu)
3778 res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3779
3780 return res >= 0 ? res : 0;
3781}
3782EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3783
3784int sock_inuse_get(struct net *net)
3785{
3786 int cpu, res = 0;
3787
3788 for_each_possible_cpu(cpu)
3789 res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3790
3791 return res;
3792}
3793
3794EXPORT_SYMBOL_GPL(sock_inuse_get);
3795
3796static int __net_init sock_inuse_init_net(struct net *net)
3797{
3798 net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3799 if (net->core.prot_inuse == NULL)
3800 return -ENOMEM;
3801 return 0;
3802}
3803
3804static void __net_exit sock_inuse_exit_net(struct net *net)
3805{
3806 free_percpu(net->core.prot_inuse);
3807}
3808
3809static struct pernet_operations net_inuse_ops = {
3810 .init = sock_inuse_init_net,
3811 .exit = sock_inuse_exit_net,
3812};
3813
3814static __init int net_inuse_init(void)
3815{
3816 if (register_pernet_subsys(&net_inuse_ops))
3817 panic("Cannot initialize net inuse counters");
3818
3819 return 0;
3820}
3821
3822core_initcall(net_inuse_init);
3823
3824static int assign_proto_idx(struct proto *prot)
3825{
3826 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3827
3828 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3829 pr_err("PROTO_INUSE_NR exhausted\n");
3830 return -ENOSPC;
3831 }
3832
3833 set_bit(prot->inuse_idx, proto_inuse_idx);
3834 return 0;
3835}
3836
3837static void release_proto_idx(struct proto *prot)
3838{
3839 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3840 clear_bit(prot->inuse_idx, proto_inuse_idx);
3841}
3842#else
3843static inline int assign_proto_idx(struct proto *prot)
3844{
3845 return 0;
3846}
3847
3848static inline void release_proto_idx(struct proto *prot)
3849{
3850}
3851
3852#endif
3853
3854static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3855{
3856 if (!twsk_prot)
3857 return;
3858 kfree(twsk_prot->twsk_slab_name);
3859 twsk_prot->twsk_slab_name = NULL;
3860 kmem_cache_destroy(twsk_prot->twsk_slab);
3861 twsk_prot->twsk_slab = NULL;
3862}
3863
3864static int tw_prot_init(const struct proto *prot)
3865{
3866 struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
3867
3868 if (!twsk_prot)
3869 return 0;
3870
3871 twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
3872 prot->name);
3873 if (!twsk_prot->twsk_slab_name)
3874 return -ENOMEM;
3875
3876 twsk_prot->twsk_slab =
3877 kmem_cache_create(twsk_prot->twsk_slab_name,
3878 twsk_prot->twsk_obj_size, 0,
3879 SLAB_ACCOUNT | prot->slab_flags,
3880 NULL);
3881 if (!twsk_prot->twsk_slab) {
3882 pr_crit("%s: Can't create timewait sock SLAB cache!\n",
3883 prot->name);
3884 return -ENOMEM;
3885 }
3886
3887 return 0;
3888}
3889
3890static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3891{
3892 if (!rsk_prot)
3893 return;
3894 kfree(rsk_prot->slab_name);
3895 rsk_prot->slab_name = NULL;
3896 kmem_cache_destroy(rsk_prot->slab);
3897 rsk_prot->slab = NULL;
3898}
3899
3900static int req_prot_init(const struct proto *prot)
3901{
3902 struct request_sock_ops *rsk_prot = prot->rsk_prot;
3903
3904 if (!rsk_prot)
3905 return 0;
3906
3907 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3908 prot->name);
3909 if (!rsk_prot->slab_name)
3910 return -ENOMEM;
3911
3912 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3913 rsk_prot->obj_size, 0,
3914 SLAB_ACCOUNT | prot->slab_flags,
3915 NULL);
3916
3917 if (!rsk_prot->slab) {
3918 pr_crit("%s: Can't create request sock SLAB cache!\n",
3919 prot->name);
3920 return -ENOMEM;
3921 }
3922 return 0;
3923}
3924
3925int proto_register(struct proto *prot, int alloc_slab)
3926{
3927 int ret = -ENOBUFS;
3928
3929 if (prot->memory_allocated && !prot->sysctl_mem) {
3930 pr_err("%s: missing sysctl_mem\n", prot->name);
3931 return -EINVAL;
3932 }
3933 if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
3934 pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
3935 return -EINVAL;
3936 }
3937 if (alloc_slab) {
3938 prot->slab = kmem_cache_create_usercopy(prot->name,
3939 prot->obj_size, 0,
3940 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3941 prot->slab_flags,
3942 prot->useroffset, prot->usersize,
3943 NULL);
3944
3945 if (prot->slab == NULL) {
3946 pr_crit("%s: Can't create sock SLAB cache!\n",
3947 prot->name);
3948 goto out;
3949 }
3950
3951 if (req_prot_init(prot))
3952 goto out_free_request_sock_slab;
3953
3954 if (tw_prot_init(prot))
3955 goto out_free_timewait_sock_slab;
3956 }
3957
3958 mutex_lock(&proto_list_mutex);
3959 ret = assign_proto_idx(prot);
3960 if (ret) {
3961 mutex_unlock(&proto_list_mutex);
3962 goto out_free_timewait_sock_slab;
3963 }
3964 list_add(&prot->node, &proto_list);
3965 mutex_unlock(&proto_list_mutex);
3966 return ret;
3967
3968out_free_timewait_sock_slab:
3969 if (alloc_slab)
3970 tw_prot_cleanup(prot->twsk_prot);
3971out_free_request_sock_slab:
3972 if (alloc_slab) {
3973 req_prot_cleanup(prot->rsk_prot);
3974
3975 kmem_cache_destroy(prot->slab);
3976 prot->slab = NULL;
3977 }
3978out:
3979 return ret;
3980}
3981EXPORT_SYMBOL(proto_register);
3982
3983void proto_unregister(struct proto *prot)
3984{
3985 mutex_lock(&proto_list_mutex);
3986 release_proto_idx(prot);
3987 list_del(&prot->node);
3988 mutex_unlock(&proto_list_mutex);
3989
3990 kmem_cache_destroy(prot->slab);
3991 prot->slab = NULL;
3992
3993 req_prot_cleanup(prot->rsk_prot);
3994 tw_prot_cleanup(prot->twsk_prot);
3995}
3996EXPORT_SYMBOL(proto_unregister);
3997
3998int sock_load_diag_module(int family, int protocol)
3999{
4000 if (!protocol) {
4001 if (!sock_is_registered(family))
4002 return -ENOENT;
4003
4004 return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4005 NETLINK_SOCK_DIAG, family);
4006 }
4007
4008#ifdef CONFIG_INET
4009 if (family == AF_INET &&
4010 protocol != IPPROTO_RAW &&
4011 protocol < MAX_INET_PROTOS &&
4012 !rcu_access_pointer(inet_protos[protocol]))
4013 return -ENOENT;
4014#endif
4015
4016 return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4017 NETLINK_SOCK_DIAG, family, protocol);
4018}
4019EXPORT_SYMBOL(sock_load_diag_module);
4020
4021#ifdef CONFIG_PROC_FS
4022static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4023 __acquires(proto_list_mutex)
4024{
4025 mutex_lock(&proto_list_mutex);
4026 return seq_list_start_head(&proto_list, *pos);
4027}
4028
4029static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4030{
4031 return seq_list_next(v, &proto_list, pos);
4032}
4033
4034static void proto_seq_stop(struct seq_file *seq, void *v)
4035 __releases(proto_list_mutex)
4036{
4037 mutex_unlock(&proto_list_mutex);
4038}
4039
4040static char proto_method_implemented(const void *method)
4041{
4042 return method == NULL ? 'n' : 'y';
4043}
4044static long sock_prot_memory_allocated(struct proto *proto)
4045{
4046 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4047}
4048
4049static const char *sock_prot_memory_pressure(struct proto *proto)
4050{
4051 return proto->memory_pressure != NULL ?
4052 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4053}
4054
4055static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4056{
4057
4058 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
4059 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4060 proto->name,
4061 proto->obj_size,
4062 sock_prot_inuse_get(seq_file_net(seq), proto),
4063 sock_prot_memory_allocated(proto),
4064 sock_prot_memory_pressure(proto),
4065 proto->max_header,
4066 proto->slab == NULL ? "no" : "yes",
4067 module_name(proto->owner),
4068 proto_method_implemented(proto->close),
4069 proto_method_implemented(proto->connect),
4070 proto_method_implemented(proto->disconnect),
4071 proto_method_implemented(proto->accept),
4072 proto_method_implemented(proto->ioctl),
4073 proto_method_implemented(proto->init),
4074 proto_method_implemented(proto->destroy),
4075 proto_method_implemented(proto->shutdown),
4076 proto_method_implemented(proto->setsockopt),
4077 proto_method_implemented(proto->getsockopt),
4078 proto_method_implemented(proto->sendmsg),
4079 proto_method_implemented(proto->recvmsg),
4080 proto_method_implemented(proto->bind),
4081 proto_method_implemented(proto->backlog_rcv),
4082 proto_method_implemented(proto->hash),
4083 proto_method_implemented(proto->unhash),
4084 proto_method_implemented(proto->get_port),
4085 proto_method_implemented(proto->enter_memory_pressure));
4086}
4087
4088static int proto_seq_show(struct seq_file *seq, void *v)
4089{
4090 if (v == &proto_list)
4091 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4092 "protocol",
4093 "size",
4094 "sockets",
4095 "memory",
4096 "press",
4097 "maxhdr",
4098 "slab",
4099 "module",
4100 "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4101 else
4102 proto_seq_printf(seq, list_entry(v, struct proto, node));
4103 return 0;
4104}
4105
4106static const struct seq_operations proto_seq_ops = {
4107 .start = proto_seq_start,
4108 .next = proto_seq_next,
4109 .stop = proto_seq_stop,
4110 .show = proto_seq_show,
4111};
4112
4113static __net_init int proto_init_net(struct net *net)
4114{
4115 if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4116 sizeof(struct seq_net_private)))
4117 return -ENOMEM;
4118
4119 return 0;
4120}
4121
4122static __net_exit void proto_exit_net(struct net *net)
4123{
4124 remove_proc_entry("protocols", net->proc_net);
4125}
4126
4127
4128static __net_initdata struct pernet_operations proto_net_ops = {
4129 .init = proto_init_net,
4130 .exit = proto_exit_net,
4131};
4132
4133static int __init proto_init(void)
4134{
4135 return register_pernet_subsys(&proto_net_ops);
4136}
4137
4138subsys_initcall(proto_init);
4139
4140#endif /* PROC_FS */
4141
4142#ifdef CONFIG_NET_RX_BUSY_POLL
4143bool sk_busy_loop_end(void *p, unsigned long start_time)
4144{
4145 struct sock *sk = p;
4146
4147 if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4148 return true;
4149
4150 if (sk_is_udp(sk) &&
4151 !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4152 return true;
4153
4154 return sk_busy_loop_timeout(sk, start_time);
4155}
4156EXPORT_SYMBOL(sk_busy_loop_end);
4157#endif /* CONFIG_NET_RX_BUSY_POLL */
4158
4159int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4160{
4161 if (!sk->sk_prot->bind_add)
4162 return -EOPNOTSUPP;
4163 return sk->sk_prot->bind_add(sk, addr, addr_len);
4164}
4165EXPORT_SYMBOL(sock_bind_add);
4166
4167/* Copy 'size' bytes from userspace and return `size` back to userspace */
4168int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4169 void __user *arg, void *karg, size_t size)
4170{
4171 int ret;
4172
4173 if (copy_from_user(karg, arg, size))
4174 return -EFAULT;
4175
4176 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4177 if (ret)
4178 return ret;
4179
4180 if (copy_to_user(arg, karg, size))
4181 return -EFAULT;
4182
4183 return 0;
4184}
4185EXPORT_SYMBOL(sock_ioctl_inout);
4186
4187/* This is the most common ioctl prep function, where the result (4 bytes) is
4188 * copied back to userspace if the ioctl() returns successfully. No input is
4189 * copied from userspace as input argument.
4190 */
4191static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4192{
4193 int ret, karg = 0;
4194
4195 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4196 if (ret)
4197 return ret;
4198
4199 return put_user(karg, (int __user *)arg);
4200}
4201
4202/* A wrapper around sock ioctls, which copies the data from userspace
4203 * (depending on the protocol/ioctl), and copies back the result to userspace.
4204 * The main motivation for this function is to pass kernel memory to the
4205 * protocol ioctl callbacks, instead of userspace memory.
4206 */
4207int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4208{
4209 int rc = 1;
4210
4211 if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4212 rc = ipmr_sk_ioctl(sk, cmd, arg);
4213 else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4214 rc = ip6mr_sk_ioctl(sk, cmd, arg);
4215 else if (sk_is_phonet(sk))
4216 rc = phonet_sk_ioctl(sk, cmd, arg);
4217
4218 /* If ioctl was processed, returns its value */
4219 if (rc <= 0)
4220 return rc;
4221
4222 /* Otherwise call the default handler */
4223 return sock_ioctl_out(sk, cmd, arg);
4224}
4225EXPORT_SYMBOL(sk_ioctl);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Generic socket support routines. Memory allocators, socket lock/release
8 * handler for protocols to use and generic option handler.
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
87
88#include <asm/unaligned.h>
89#include <linux/capability.h>
90#include <linux/errno.h>
91#include <linux/errqueue.h>
92#include <linux/types.h>
93#include <linux/socket.h>
94#include <linux/in.h>
95#include <linux/kernel.h>
96#include <linux/module.h>
97#include <linux/proc_fs.h>
98#include <linux/seq_file.h>
99#include <linux/sched.h>
100#include <linux/sched/mm.h>
101#include <linux/timer.h>
102#include <linux/string.h>
103#include <linux/sockios.h>
104#include <linux/net.h>
105#include <linux/mm.h>
106#include <linux/slab.h>
107#include <linux/interrupt.h>
108#include <linux/poll.h>
109#include <linux/tcp.h>
110#include <linux/init.h>
111#include <linux/highmem.h>
112#include <linux/user_namespace.h>
113#include <linux/static_key.h>
114#include <linux/memcontrol.h>
115#include <linux/prefetch.h>
116#include <linux/compat.h>
117
118#include <linux/uaccess.h>
119
120#include <linux/netdevice.h>
121#include <net/protocol.h>
122#include <linux/skbuff.h>
123#include <net/net_namespace.h>
124#include <net/request_sock.h>
125#include <net/sock.h>
126#include <linux/net_tstamp.h>
127#include <net/xfrm.h>
128#include <linux/ipsec.h>
129#include <net/cls_cgroup.h>
130#include <net/netprio_cgroup.h>
131#include <linux/sock_diag.h>
132
133#include <linux/filter.h>
134#include <net/sock_reuseport.h>
135#include <net/bpf_sk_storage.h>
136
137#include <trace/events/sock.h>
138
139#include <net/tcp.h>
140#include <net/busy_poll.h>
141
142static DEFINE_MUTEX(proto_list_mutex);
143static LIST_HEAD(proto_list);
144
145static void sock_inuse_add(struct net *net, int val);
146
147/**
148 * sk_ns_capable - General socket capability test
149 * @sk: Socket to use a capability on or through
150 * @user_ns: The user namespace of the capability to use
151 * @cap: The capability to use
152 *
153 * Test to see if the opener of the socket had when the socket was
154 * created and the current process has the capability @cap in the user
155 * namespace @user_ns.
156 */
157bool sk_ns_capable(const struct sock *sk,
158 struct user_namespace *user_ns, int cap)
159{
160 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
161 ns_capable(user_ns, cap);
162}
163EXPORT_SYMBOL(sk_ns_capable);
164
165/**
166 * sk_capable - Socket global capability test
167 * @sk: Socket to use a capability on or through
168 * @cap: The global capability to use
169 *
170 * Test to see if the opener of the socket had when the socket was
171 * created and the current process has the capability @cap in all user
172 * namespaces.
173 */
174bool sk_capable(const struct sock *sk, int cap)
175{
176 return sk_ns_capable(sk, &init_user_ns, cap);
177}
178EXPORT_SYMBOL(sk_capable);
179
180/**
181 * sk_net_capable - Network namespace socket capability test
182 * @sk: Socket to use a capability on or through
183 * @cap: The capability to use
184 *
185 * Test to see if the opener of the socket had when the socket was created
186 * and the current process has the capability @cap over the network namespace
187 * the socket is a member of.
188 */
189bool sk_net_capable(const struct sock *sk, int cap)
190{
191 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
192}
193EXPORT_SYMBOL(sk_net_capable);
194
195/*
196 * Each address family might have different locking rules, so we have
197 * one slock key per address family and separate keys for internal and
198 * userspace sockets.
199 */
200static struct lock_class_key af_family_keys[AF_MAX];
201static struct lock_class_key af_family_kern_keys[AF_MAX];
202static struct lock_class_key af_family_slock_keys[AF_MAX];
203static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
204
205/*
206 * Make lock validator output more readable. (we pre-construct these
207 * strings build-time, so that runtime initialization of socket
208 * locks is fast):
209 */
210
211#define _sock_locks(x) \
212 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \
213 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \
214 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \
215 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \
216 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \
217 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \
218 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \
219 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \
220 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \
221 x "27" , x "28" , x "AF_CAN" , \
222 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \
223 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \
224 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \
225 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \
226 x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \
227 x "AF_MAX"
228
229static const char *const af_family_key_strings[AF_MAX+1] = {
230 _sock_locks("sk_lock-")
231};
232static const char *const af_family_slock_key_strings[AF_MAX+1] = {
233 _sock_locks("slock-")
234};
235static const char *const af_family_clock_key_strings[AF_MAX+1] = {
236 _sock_locks("clock-")
237};
238
239static const char *const af_family_kern_key_strings[AF_MAX+1] = {
240 _sock_locks("k-sk_lock-")
241};
242static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
243 _sock_locks("k-slock-")
244};
245static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
246 _sock_locks("k-clock-")
247};
248static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
249 _sock_locks("rlock-")
250};
251static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
252 _sock_locks("wlock-")
253};
254static const char *const af_family_elock_key_strings[AF_MAX+1] = {
255 _sock_locks("elock-")
256};
257
258/*
259 * sk_callback_lock and sk queues locking rules are per-address-family,
260 * so split the lock classes by using a per-AF key:
261 */
262static struct lock_class_key af_callback_keys[AF_MAX];
263static struct lock_class_key af_rlock_keys[AF_MAX];
264static struct lock_class_key af_wlock_keys[AF_MAX];
265static struct lock_class_key af_elock_keys[AF_MAX];
266static struct lock_class_key af_kern_callback_keys[AF_MAX];
267
268/* Run time adjustable parameters. */
269__u32 sysctl_wmem_max __read_mostly = SK_WMEM_MAX;
270EXPORT_SYMBOL(sysctl_wmem_max);
271__u32 sysctl_rmem_max __read_mostly = SK_RMEM_MAX;
272EXPORT_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 */
277int sysctl_optmem_max __read_mostly = sizeof(unsigned long)*(2*UIO_MAXIOV+512);
278EXPORT_SYMBOL(sysctl_optmem_max);
279
280int sysctl_tstamp_allow_data __read_mostly = 1;
281
282DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
283EXPORT_SYMBOL_GPL(memalloc_socks_key);
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 */
293void sk_set_memalloc(struct sock *sk)
294{
295 sock_set_flag(sk, SOCK_MEMALLOC);
296 sk->sk_allocation |= __GFP_MEMALLOC;
297 static_branch_inc(&memalloc_socks_key);
298}
299EXPORT_SYMBOL_GPL(sk_set_memalloc);
300
301void sk_clear_memalloc(struct sock *sk)
302{
303 sock_reset_flag(sk, SOCK_MEMALLOC);
304 sk->sk_allocation &= ~__GFP_MEMALLOC;
305 static_branch_dec(&memalloc_socks_key);
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}
316EXPORT_SYMBOL_GPL(sk_clear_memalloc);
317
318int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
319{
320 int ret;
321 unsigned int noreclaim_flag;
322
323 /* these should have been dropped before queueing */
324 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
325
326 noreclaim_flag = memalloc_noreclaim_save();
327 ret = sk->sk_backlog_rcv(sk, skb);
328 memalloc_noreclaim_restore(noreclaim_flag);
329
330 return ret;
331}
332EXPORT_SYMBOL(__sk_backlog_rcv);
333
334static int sock_get_timeout(long timeo, void *optval, bool old_timeval)
335{
336 struct __kernel_sock_timeval tv;
337
338 if (timeo == MAX_SCHEDULE_TIMEOUT) {
339 tv.tv_sec = 0;
340 tv.tv_usec = 0;
341 } else {
342 tv.tv_sec = timeo / HZ;
343 tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
344 }
345
346 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
347 struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
348 *(struct old_timeval32 *)optval = tv32;
349 return sizeof(tv32);
350 }
351
352 if (old_timeval) {
353 struct __kernel_old_timeval old_tv;
354 old_tv.tv_sec = tv.tv_sec;
355 old_tv.tv_usec = tv.tv_usec;
356 *(struct __kernel_old_timeval *)optval = old_tv;
357 return sizeof(old_tv);
358 }
359
360 *(struct __kernel_sock_timeval *)optval = tv;
361 return sizeof(tv);
362}
363
364static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
365 bool old_timeval)
366{
367 struct __kernel_sock_timeval tv;
368
369 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
370 struct old_timeval32 tv32;
371
372 if (optlen < sizeof(tv32))
373 return -EINVAL;
374
375 if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
376 return -EFAULT;
377 tv.tv_sec = tv32.tv_sec;
378 tv.tv_usec = tv32.tv_usec;
379 } else if (old_timeval) {
380 struct __kernel_old_timeval old_tv;
381
382 if (optlen < sizeof(old_tv))
383 return -EINVAL;
384 if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
385 return -EFAULT;
386 tv.tv_sec = old_tv.tv_sec;
387 tv.tv_usec = old_tv.tv_usec;
388 } else {
389 if (optlen < sizeof(tv))
390 return -EINVAL;
391 if (copy_from_sockptr(&tv, optval, sizeof(tv)))
392 return -EFAULT;
393 }
394 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
395 return -EDOM;
396
397 if (tv.tv_sec < 0) {
398 static int warned __read_mostly;
399
400 *timeo_p = 0;
401 if (warned < 10 && net_ratelimit()) {
402 warned++;
403 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
404 __func__, current->comm, task_pid_nr(current));
405 }
406 return 0;
407 }
408 *timeo_p = MAX_SCHEDULE_TIMEOUT;
409 if (tv.tv_sec == 0 && tv.tv_usec == 0)
410 return 0;
411 if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1))
412 *timeo_p = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec, USEC_PER_SEC / HZ);
413 return 0;
414}
415
416static void sock_warn_obsolete_bsdism(const char *name)
417{
418 static int warned;
419 static char warncomm[TASK_COMM_LEN];
420 if (strcmp(warncomm, current->comm) && warned < 5) {
421 strcpy(warncomm, current->comm);
422 pr_warn("process `%s' is using obsolete %s SO_BSDCOMPAT\n",
423 warncomm, name);
424 warned++;
425 }
426}
427
428static bool sock_needs_netstamp(const struct sock *sk)
429{
430 switch (sk->sk_family) {
431 case AF_UNSPEC:
432 case AF_UNIX:
433 return false;
434 default:
435 return true;
436 }
437}
438
439static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
440{
441 if (sk->sk_flags & flags) {
442 sk->sk_flags &= ~flags;
443 if (sock_needs_netstamp(sk) &&
444 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
445 net_disable_timestamp();
446 }
447}
448
449
450int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
451{
452 unsigned long flags;
453 struct sk_buff_head *list = &sk->sk_receive_queue;
454
455 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) {
456 atomic_inc(&sk->sk_drops);
457 trace_sock_rcvqueue_full(sk, skb);
458 return -ENOMEM;
459 }
460
461 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
462 atomic_inc(&sk->sk_drops);
463 return -ENOBUFS;
464 }
465
466 skb->dev = NULL;
467 skb_set_owner_r(skb, sk);
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 sock_skb_set_dropcount(sk, skb);
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}
483EXPORT_SYMBOL(__sock_queue_rcv_skb);
484
485int sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
486{
487 int err;
488
489 err = sk_filter(sk, skb);
490 if (err)
491 return err;
492
493 return __sock_queue_rcv_skb(sk, skb);
494}
495EXPORT_SYMBOL(sock_queue_rcv_skb);
496
497int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
498 const int nested, unsigned int trim_cap, bool refcounted)
499{
500 int rc = NET_RX_SUCCESS;
501
502 if (sk_filter_trim_cap(sk, skb, trim_cap))
503 goto discard_and_relse;
504
505 skb->dev = NULL;
506
507 if (sk_rcvqueues_full(sk, sk->sk_rcvbuf)) {
508 atomic_inc(&sk->sk_drops);
509 goto discard_and_relse;
510 }
511 if (nested)
512 bh_lock_sock_nested(sk);
513 else
514 bh_lock_sock(sk);
515 if (!sock_owned_by_user(sk)) {
516 /*
517 * trylock + unlock semantics:
518 */
519 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
520
521 rc = sk_backlog_rcv(sk, skb);
522
523 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
524 } else if (sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf))) {
525 bh_unlock_sock(sk);
526 atomic_inc(&sk->sk_drops);
527 goto discard_and_relse;
528 }
529
530 bh_unlock_sock(sk);
531out:
532 if (refcounted)
533 sock_put(sk);
534 return rc;
535discard_and_relse:
536 kfree_skb(skb);
537 goto out;
538}
539EXPORT_SYMBOL(__sk_receive_skb);
540
541struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
542{
543 struct dst_entry *dst = __sk_dst_get(sk);
544
545 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
546 sk_tx_queue_clear(sk);
547 sk->sk_dst_pending_confirm = 0;
548 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
549 dst_release(dst);
550 return NULL;
551 }
552
553 return dst;
554}
555EXPORT_SYMBOL(__sk_dst_check);
556
557struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
558{
559 struct dst_entry *dst = sk_dst_get(sk);
560
561 if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
562 sk_dst_reset(sk);
563 dst_release(dst);
564 return NULL;
565 }
566
567 return dst;
568}
569EXPORT_SYMBOL(sk_dst_check);
570
571static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
572{
573 int ret = -ENOPROTOOPT;
574#ifdef CONFIG_NETDEVICES
575 struct net *net = sock_net(sk);
576
577 /* Sorry... */
578 ret = -EPERM;
579 if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
580 goto out;
581
582 ret = -EINVAL;
583 if (ifindex < 0)
584 goto out;
585
586 sk->sk_bound_dev_if = ifindex;
587 if (sk->sk_prot->rehash)
588 sk->sk_prot->rehash(sk);
589 sk_dst_reset(sk);
590
591 ret = 0;
592
593out:
594#endif
595
596 return ret;
597}
598
599int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
600{
601 int ret;
602
603 if (lock_sk)
604 lock_sock(sk);
605 ret = sock_bindtoindex_locked(sk, ifindex);
606 if (lock_sk)
607 release_sock(sk);
608
609 return ret;
610}
611EXPORT_SYMBOL(sock_bindtoindex);
612
613static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
614{
615 int ret = -ENOPROTOOPT;
616#ifdef CONFIG_NETDEVICES
617 struct net *net = sock_net(sk);
618 char devname[IFNAMSIZ];
619 int index;
620
621 ret = -EINVAL;
622 if (optlen < 0)
623 goto out;
624
625 /* Bind this socket to a particular device like "eth0",
626 * as specified in the passed interface name. If the
627 * name is "" or the option length is zero the socket
628 * is not bound.
629 */
630 if (optlen > IFNAMSIZ - 1)
631 optlen = IFNAMSIZ - 1;
632 memset(devname, 0, sizeof(devname));
633
634 ret = -EFAULT;
635 if (copy_from_sockptr(devname, optval, optlen))
636 goto out;
637
638 index = 0;
639 if (devname[0] != '\0') {
640 struct net_device *dev;
641
642 rcu_read_lock();
643 dev = dev_get_by_name_rcu(net, devname);
644 if (dev)
645 index = dev->ifindex;
646 rcu_read_unlock();
647 ret = -ENODEV;
648 if (!dev)
649 goto out;
650 }
651
652 return sock_bindtoindex(sk, index, true);
653out:
654#endif
655
656 return ret;
657}
658
659static int sock_getbindtodevice(struct sock *sk, char __user *optval,
660 int __user *optlen, int len)
661{
662 int ret = -ENOPROTOOPT;
663#ifdef CONFIG_NETDEVICES
664 struct net *net = sock_net(sk);
665 char devname[IFNAMSIZ];
666
667 if (sk->sk_bound_dev_if == 0) {
668 len = 0;
669 goto zero;
670 }
671
672 ret = -EINVAL;
673 if (len < IFNAMSIZ)
674 goto out;
675
676 ret = netdev_get_name(net, devname, sk->sk_bound_dev_if);
677 if (ret)
678 goto out;
679
680 len = strlen(devname) + 1;
681
682 ret = -EFAULT;
683 if (copy_to_user(optval, devname, len))
684 goto out;
685
686zero:
687 ret = -EFAULT;
688 if (put_user(len, optlen))
689 goto out;
690
691 ret = 0;
692
693out:
694#endif
695
696 return ret;
697}
698
699bool sk_mc_loop(struct sock *sk)
700{
701 if (dev_recursion_level())
702 return false;
703 if (!sk)
704 return true;
705 switch (sk->sk_family) {
706 case AF_INET:
707 return inet_sk(sk)->mc_loop;
708#if IS_ENABLED(CONFIG_IPV6)
709 case AF_INET6:
710 return inet6_sk(sk)->mc_loop;
711#endif
712 }
713 WARN_ON_ONCE(1);
714 return true;
715}
716EXPORT_SYMBOL(sk_mc_loop);
717
718void sock_set_reuseaddr(struct sock *sk)
719{
720 lock_sock(sk);
721 sk->sk_reuse = SK_CAN_REUSE;
722 release_sock(sk);
723}
724EXPORT_SYMBOL(sock_set_reuseaddr);
725
726void sock_set_reuseport(struct sock *sk)
727{
728 lock_sock(sk);
729 sk->sk_reuseport = true;
730 release_sock(sk);
731}
732EXPORT_SYMBOL(sock_set_reuseport);
733
734void sock_no_linger(struct sock *sk)
735{
736 lock_sock(sk);
737 sk->sk_lingertime = 0;
738 sock_set_flag(sk, SOCK_LINGER);
739 release_sock(sk);
740}
741EXPORT_SYMBOL(sock_no_linger);
742
743void sock_set_priority(struct sock *sk, u32 priority)
744{
745 lock_sock(sk);
746 sk->sk_priority = priority;
747 release_sock(sk);
748}
749EXPORT_SYMBOL(sock_set_priority);
750
751void sock_set_sndtimeo(struct sock *sk, s64 secs)
752{
753 lock_sock(sk);
754 if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
755 sk->sk_sndtimeo = secs * HZ;
756 else
757 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
758 release_sock(sk);
759}
760EXPORT_SYMBOL(sock_set_sndtimeo);
761
762static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
763{
764 if (val) {
765 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
766 sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, ns);
767 sock_set_flag(sk, SOCK_RCVTSTAMP);
768 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
769 } else {
770 sock_reset_flag(sk, SOCK_RCVTSTAMP);
771 sock_reset_flag(sk, SOCK_RCVTSTAMPNS);
772 sock_reset_flag(sk, SOCK_TSTAMP_NEW);
773 }
774}
775
776void sock_enable_timestamps(struct sock *sk)
777{
778 lock_sock(sk);
779 __sock_set_timestamps(sk, true, false, true);
780 release_sock(sk);
781}
782EXPORT_SYMBOL(sock_enable_timestamps);
783
784void sock_set_keepalive(struct sock *sk)
785{
786 lock_sock(sk);
787 if (sk->sk_prot->keepalive)
788 sk->sk_prot->keepalive(sk, true);
789 sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
790 release_sock(sk);
791}
792EXPORT_SYMBOL(sock_set_keepalive);
793
794static void __sock_set_rcvbuf(struct sock *sk, int val)
795{
796 /* Ensure val * 2 fits into an int, to prevent max_t() from treating it
797 * as a negative value.
798 */
799 val = min_t(int, val, INT_MAX / 2);
800 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
801
802 /* We double it on the way in to account for "struct sk_buff" etc.
803 * overhead. Applications assume that the SO_RCVBUF setting they make
804 * will allow that much actual data to be received on that socket.
805 *
806 * Applications are unaware that "struct sk_buff" and other overheads
807 * allocate from the receive buffer during socket buffer allocation.
808 *
809 * And after considering the possible alternatives, returning the value
810 * we actually used in getsockopt is the most desirable behavior.
811 */
812 WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
813}
814
815void sock_set_rcvbuf(struct sock *sk, int val)
816{
817 lock_sock(sk);
818 __sock_set_rcvbuf(sk, val);
819 release_sock(sk);
820}
821EXPORT_SYMBOL(sock_set_rcvbuf);
822
823void sock_set_mark(struct sock *sk, u32 val)
824{
825 lock_sock(sk);
826 sk->sk_mark = val;
827 release_sock(sk);
828}
829EXPORT_SYMBOL(sock_set_mark);
830
831/*
832 * This is meant for all protocols to use and covers goings on
833 * at the socket level. Everything here is generic.
834 */
835
836int sock_setsockopt(struct socket *sock, int level, int optname,
837 sockptr_t optval, unsigned int optlen)
838{
839 struct sock_txtime sk_txtime;
840 struct sock *sk = sock->sk;
841 int val;
842 int valbool;
843 struct linger ling;
844 int ret = 0;
845
846 /*
847 * Options without arguments
848 */
849
850 if (optname == SO_BINDTODEVICE)
851 return sock_setbindtodevice(sk, optval, optlen);
852
853 if (optlen < sizeof(int))
854 return -EINVAL;
855
856 if (copy_from_sockptr(&val, optval, sizeof(val)))
857 return -EFAULT;
858
859 valbool = val ? 1 : 0;
860
861 lock_sock(sk);
862
863 switch (optname) {
864 case SO_DEBUG:
865 if (val && !capable(CAP_NET_ADMIN))
866 ret = -EACCES;
867 else
868 sock_valbool_flag(sk, SOCK_DBG, valbool);
869 break;
870 case SO_REUSEADDR:
871 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
872 break;
873 case SO_REUSEPORT:
874 sk->sk_reuseport = valbool;
875 break;
876 case SO_TYPE:
877 case SO_PROTOCOL:
878 case SO_DOMAIN:
879 case SO_ERROR:
880 ret = -ENOPROTOOPT;
881 break;
882 case SO_DONTROUTE:
883 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
884 sk_dst_reset(sk);
885 break;
886 case SO_BROADCAST:
887 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
888 break;
889 case SO_SNDBUF:
890 /* Don't error on this BSD doesn't and if you think
891 * about it this is right. Otherwise apps have to
892 * play 'guess the biggest size' games. RCVBUF/SNDBUF
893 * are treated in BSD as hints
894 */
895 val = min_t(u32, val, sysctl_wmem_max);
896set_sndbuf:
897 /* Ensure val * 2 fits into an int, to prevent max_t()
898 * from treating it as a negative value.
899 */
900 val = min_t(int, val, INT_MAX / 2);
901 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
902 WRITE_ONCE(sk->sk_sndbuf,
903 max_t(int, val * 2, SOCK_MIN_SNDBUF));
904 /* Wake up sending tasks if we upped the value. */
905 sk->sk_write_space(sk);
906 break;
907
908 case SO_SNDBUFFORCE:
909 if (!capable(CAP_NET_ADMIN)) {
910 ret = -EPERM;
911 break;
912 }
913
914 /* No negative values (to prevent underflow, as val will be
915 * multiplied by 2).
916 */
917 if (val < 0)
918 val = 0;
919 goto set_sndbuf;
920
921 case SO_RCVBUF:
922 /* Don't error on this BSD doesn't and if you think
923 * about it this is right. Otherwise apps have to
924 * play 'guess the biggest size' games. RCVBUF/SNDBUF
925 * are treated in BSD as hints
926 */
927 __sock_set_rcvbuf(sk, min_t(u32, val, sysctl_rmem_max));
928 break;
929
930 case SO_RCVBUFFORCE:
931 if (!capable(CAP_NET_ADMIN)) {
932 ret = -EPERM;
933 break;
934 }
935
936 /* No negative values (to prevent underflow, as val will be
937 * multiplied by 2).
938 */
939 __sock_set_rcvbuf(sk, max(val, 0));
940 break;
941
942 case SO_KEEPALIVE:
943 if (sk->sk_prot->keepalive)
944 sk->sk_prot->keepalive(sk, valbool);
945 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
946 break;
947
948 case SO_OOBINLINE:
949 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
950 break;
951
952 case SO_NO_CHECK:
953 sk->sk_no_check_tx = valbool;
954 break;
955
956 case SO_PRIORITY:
957 if ((val >= 0 && val <= 6) ||
958 ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
959 sk->sk_priority = val;
960 else
961 ret = -EPERM;
962 break;
963
964 case SO_LINGER:
965 if (optlen < sizeof(ling)) {
966 ret = -EINVAL; /* 1003.1g */
967 break;
968 }
969 if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
970 ret = -EFAULT;
971 break;
972 }
973 if (!ling.l_onoff)
974 sock_reset_flag(sk, SOCK_LINGER);
975 else {
976#if (BITS_PER_LONG == 32)
977 if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ)
978 sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT;
979 else
980#endif
981 sk->sk_lingertime = (unsigned int)ling.l_linger * HZ;
982 sock_set_flag(sk, SOCK_LINGER);
983 }
984 break;
985
986 case SO_BSDCOMPAT:
987 sock_warn_obsolete_bsdism("setsockopt");
988 break;
989
990 case SO_PASSCRED:
991 if (valbool)
992 set_bit(SOCK_PASSCRED, &sock->flags);
993 else
994 clear_bit(SOCK_PASSCRED, &sock->flags);
995 break;
996
997 case SO_TIMESTAMP_OLD:
998 __sock_set_timestamps(sk, valbool, false, false);
999 break;
1000 case SO_TIMESTAMP_NEW:
1001 __sock_set_timestamps(sk, valbool, true, false);
1002 break;
1003 case SO_TIMESTAMPNS_OLD:
1004 __sock_set_timestamps(sk, valbool, false, true);
1005 break;
1006 case SO_TIMESTAMPNS_NEW:
1007 __sock_set_timestamps(sk, valbool, true, true);
1008 break;
1009 case SO_TIMESTAMPING_NEW:
1010 sock_set_flag(sk, SOCK_TSTAMP_NEW);
1011 fallthrough;
1012 case SO_TIMESTAMPING_OLD:
1013 if (val & ~SOF_TIMESTAMPING_MASK) {
1014 ret = -EINVAL;
1015 break;
1016 }
1017
1018 if (val & SOF_TIMESTAMPING_OPT_ID &&
1019 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
1020 if (sk->sk_protocol == IPPROTO_TCP &&
1021 sk->sk_type == SOCK_STREAM) {
1022 if ((1 << sk->sk_state) &
1023 (TCPF_CLOSE | TCPF_LISTEN)) {
1024 ret = -EINVAL;
1025 break;
1026 }
1027 sk->sk_tskey = tcp_sk(sk)->snd_una;
1028 } else {
1029 sk->sk_tskey = 0;
1030 }
1031 }
1032
1033 if (val & SOF_TIMESTAMPING_OPT_STATS &&
1034 !(val & SOF_TIMESTAMPING_OPT_TSONLY)) {
1035 ret = -EINVAL;
1036 break;
1037 }
1038
1039 sk->sk_tsflags = val;
1040 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
1041 sock_enable_timestamp(sk,
1042 SOCK_TIMESTAMPING_RX_SOFTWARE);
1043 else {
1044 if (optname == SO_TIMESTAMPING_NEW)
1045 sock_reset_flag(sk, SOCK_TSTAMP_NEW);
1046
1047 sock_disable_timestamp(sk,
1048 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
1049 }
1050 break;
1051
1052 case SO_RCVLOWAT:
1053 if (val < 0)
1054 val = INT_MAX;
1055 if (sock->ops->set_rcvlowat)
1056 ret = sock->ops->set_rcvlowat(sk, val);
1057 else
1058 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1059 break;
1060
1061 case SO_RCVTIMEO_OLD:
1062 case SO_RCVTIMEO_NEW:
1063 ret = sock_set_timeout(&sk->sk_rcvtimeo, optval,
1064 optlen, optname == SO_RCVTIMEO_OLD);
1065 break;
1066
1067 case SO_SNDTIMEO_OLD:
1068 case SO_SNDTIMEO_NEW:
1069 ret = sock_set_timeout(&sk->sk_sndtimeo, optval,
1070 optlen, optname == SO_SNDTIMEO_OLD);
1071 break;
1072
1073 case SO_ATTACH_FILTER: {
1074 struct sock_fprog fprog;
1075
1076 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1077 if (!ret)
1078 ret = sk_attach_filter(&fprog, sk);
1079 break;
1080 }
1081 case SO_ATTACH_BPF:
1082 ret = -EINVAL;
1083 if (optlen == sizeof(u32)) {
1084 u32 ufd;
1085
1086 ret = -EFAULT;
1087 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1088 break;
1089
1090 ret = sk_attach_bpf(ufd, sk);
1091 }
1092 break;
1093
1094 case SO_ATTACH_REUSEPORT_CBPF: {
1095 struct sock_fprog fprog;
1096
1097 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1098 if (!ret)
1099 ret = sk_reuseport_attach_filter(&fprog, sk);
1100 break;
1101 }
1102 case SO_ATTACH_REUSEPORT_EBPF:
1103 ret = -EINVAL;
1104 if (optlen == sizeof(u32)) {
1105 u32 ufd;
1106
1107 ret = -EFAULT;
1108 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1109 break;
1110
1111 ret = sk_reuseport_attach_bpf(ufd, sk);
1112 }
1113 break;
1114
1115 case SO_DETACH_REUSEPORT_BPF:
1116 ret = reuseport_detach_prog(sk);
1117 break;
1118
1119 case SO_DETACH_FILTER:
1120 ret = sk_detach_filter(sk);
1121 break;
1122
1123 case SO_LOCK_FILTER:
1124 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1125 ret = -EPERM;
1126 else
1127 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1128 break;
1129
1130 case SO_PASSSEC:
1131 if (valbool)
1132 set_bit(SOCK_PASSSEC, &sock->flags);
1133 else
1134 clear_bit(SOCK_PASSSEC, &sock->flags);
1135 break;
1136 case SO_MARK:
1137 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1138 ret = -EPERM;
1139 } else if (val != sk->sk_mark) {
1140 sk->sk_mark = val;
1141 sk_dst_reset(sk);
1142 }
1143 break;
1144
1145 case SO_RXQ_OVFL:
1146 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1147 break;
1148
1149 case SO_WIFI_STATUS:
1150 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1151 break;
1152
1153 case SO_PEEK_OFF:
1154 if (sock->ops->set_peek_off)
1155 ret = sock->ops->set_peek_off(sk, val);
1156 else
1157 ret = -EOPNOTSUPP;
1158 break;
1159
1160 case SO_NOFCS:
1161 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1162 break;
1163
1164 case SO_SELECT_ERR_QUEUE:
1165 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1166 break;
1167
1168#ifdef CONFIG_NET_RX_BUSY_POLL
1169 case SO_BUSY_POLL:
1170 /* allow unprivileged users to decrease the value */
1171 if ((val > sk->sk_ll_usec) && !capable(CAP_NET_ADMIN))
1172 ret = -EPERM;
1173 else {
1174 if (val < 0)
1175 ret = -EINVAL;
1176 else
1177 sk->sk_ll_usec = val;
1178 }
1179 break;
1180#endif
1181
1182 case SO_MAX_PACING_RATE:
1183 {
1184 unsigned long ulval = (val == ~0U) ? ~0UL : val;
1185
1186 if (sizeof(ulval) != sizeof(val) &&
1187 optlen >= sizeof(ulval) &&
1188 copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1189 ret = -EFAULT;
1190 break;
1191 }
1192 if (ulval != ~0UL)
1193 cmpxchg(&sk->sk_pacing_status,
1194 SK_PACING_NONE,
1195 SK_PACING_NEEDED);
1196 sk->sk_max_pacing_rate = ulval;
1197 sk->sk_pacing_rate = min(sk->sk_pacing_rate, ulval);
1198 break;
1199 }
1200 case SO_INCOMING_CPU:
1201 WRITE_ONCE(sk->sk_incoming_cpu, val);
1202 break;
1203
1204 case SO_CNX_ADVICE:
1205 if (val == 1)
1206 dst_negative_advice(sk);
1207 break;
1208
1209 case SO_ZEROCOPY:
1210 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1211 if (!((sk->sk_type == SOCK_STREAM &&
1212 sk->sk_protocol == IPPROTO_TCP) ||
1213 (sk->sk_type == SOCK_DGRAM &&
1214 sk->sk_protocol == IPPROTO_UDP)))
1215 ret = -ENOTSUPP;
1216 } else if (sk->sk_family != PF_RDS) {
1217 ret = -ENOTSUPP;
1218 }
1219 if (!ret) {
1220 if (val < 0 || val > 1)
1221 ret = -EINVAL;
1222 else
1223 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1224 }
1225 break;
1226
1227 case SO_TXTIME:
1228 if (optlen != sizeof(struct sock_txtime)) {
1229 ret = -EINVAL;
1230 break;
1231 } else if (copy_from_sockptr(&sk_txtime, optval,
1232 sizeof(struct sock_txtime))) {
1233 ret = -EFAULT;
1234 break;
1235 } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1236 ret = -EINVAL;
1237 break;
1238 }
1239 /* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1240 * scheduler has enough safe guards.
1241 */
1242 if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1243 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1244 ret = -EPERM;
1245 break;
1246 }
1247 sock_valbool_flag(sk, SOCK_TXTIME, true);
1248 sk->sk_clockid = sk_txtime.clockid;
1249 sk->sk_txtime_deadline_mode =
1250 !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1251 sk->sk_txtime_report_errors =
1252 !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1253 break;
1254
1255 case SO_BINDTOIFINDEX:
1256 ret = sock_bindtoindex_locked(sk, val);
1257 break;
1258
1259 default:
1260 ret = -ENOPROTOOPT;
1261 break;
1262 }
1263 release_sock(sk);
1264 return ret;
1265}
1266EXPORT_SYMBOL(sock_setsockopt);
1267
1268
1269static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1270 struct ucred *ucred)
1271{
1272 ucred->pid = pid_vnr(pid);
1273 ucred->uid = ucred->gid = -1;
1274 if (cred) {
1275 struct user_namespace *current_ns = current_user_ns();
1276
1277 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1278 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1279 }
1280}
1281
1282static int groups_to_user(gid_t __user *dst, const struct group_info *src)
1283{
1284 struct user_namespace *user_ns = current_user_ns();
1285 int i;
1286
1287 for (i = 0; i < src->ngroups; i++)
1288 if (put_user(from_kgid_munged(user_ns, src->gid[i]), dst + i))
1289 return -EFAULT;
1290
1291 return 0;
1292}
1293
1294int sock_getsockopt(struct socket *sock, int level, int optname,
1295 char __user *optval, int __user *optlen)
1296{
1297 struct sock *sk = sock->sk;
1298
1299 union {
1300 int val;
1301 u64 val64;
1302 unsigned long ulval;
1303 struct linger ling;
1304 struct old_timeval32 tm32;
1305 struct __kernel_old_timeval tm;
1306 struct __kernel_sock_timeval stm;
1307 struct sock_txtime txtime;
1308 } v;
1309
1310 int lv = sizeof(int);
1311 int len;
1312
1313 if (get_user(len, optlen))
1314 return -EFAULT;
1315 if (len < 0)
1316 return -EINVAL;
1317
1318 memset(&v, 0, sizeof(v));
1319
1320 switch (optname) {
1321 case SO_DEBUG:
1322 v.val = sock_flag(sk, SOCK_DBG);
1323 break;
1324
1325 case SO_DONTROUTE:
1326 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1327 break;
1328
1329 case SO_BROADCAST:
1330 v.val = sock_flag(sk, SOCK_BROADCAST);
1331 break;
1332
1333 case SO_SNDBUF:
1334 v.val = sk->sk_sndbuf;
1335 break;
1336
1337 case SO_RCVBUF:
1338 v.val = sk->sk_rcvbuf;
1339 break;
1340
1341 case SO_REUSEADDR:
1342 v.val = sk->sk_reuse;
1343 break;
1344
1345 case SO_REUSEPORT:
1346 v.val = sk->sk_reuseport;
1347 break;
1348
1349 case SO_KEEPALIVE:
1350 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1351 break;
1352
1353 case SO_TYPE:
1354 v.val = sk->sk_type;
1355 break;
1356
1357 case SO_PROTOCOL:
1358 v.val = sk->sk_protocol;
1359 break;
1360
1361 case SO_DOMAIN:
1362 v.val = sk->sk_family;
1363 break;
1364
1365 case SO_ERROR:
1366 v.val = -sock_error(sk);
1367 if (v.val == 0)
1368 v.val = xchg(&sk->sk_err_soft, 0);
1369 break;
1370
1371 case SO_OOBINLINE:
1372 v.val = sock_flag(sk, SOCK_URGINLINE);
1373 break;
1374
1375 case SO_NO_CHECK:
1376 v.val = sk->sk_no_check_tx;
1377 break;
1378
1379 case SO_PRIORITY:
1380 v.val = sk->sk_priority;
1381 break;
1382
1383 case SO_LINGER:
1384 lv = sizeof(v.ling);
1385 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1386 v.ling.l_linger = sk->sk_lingertime / HZ;
1387 break;
1388
1389 case SO_BSDCOMPAT:
1390 sock_warn_obsolete_bsdism("getsockopt");
1391 break;
1392
1393 case SO_TIMESTAMP_OLD:
1394 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1395 !sock_flag(sk, SOCK_TSTAMP_NEW) &&
1396 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1397 break;
1398
1399 case SO_TIMESTAMPNS_OLD:
1400 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1401 break;
1402
1403 case SO_TIMESTAMP_NEW:
1404 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1405 break;
1406
1407 case SO_TIMESTAMPNS_NEW:
1408 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1409 break;
1410
1411 case SO_TIMESTAMPING_OLD:
1412 v.val = sk->sk_tsflags;
1413 break;
1414
1415 case SO_RCVTIMEO_OLD:
1416 case SO_RCVTIMEO_NEW:
1417 lv = sock_get_timeout(sk->sk_rcvtimeo, &v, SO_RCVTIMEO_OLD == optname);
1418 break;
1419
1420 case SO_SNDTIMEO_OLD:
1421 case SO_SNDTIMEO_NEW:
1422 lv = sock_get_timeout(sk->sk_sndtimeo, &v, SO_SNDTIMEO_OLD == optname);
1423 break;
1424
1425 case SO_RCVLOWAT:
1426 v.val = sk->sk_rcvlowat;
1427 break;
1428
1429 case SO_SNDLOWAT:
1430 v.val = 1;
1431 break;
1432
1433 case SO_PASSCRED:
1434 v.val = !!test_bit(SOCK_PASSCRED, &sock->flags);
1435 break;
1436
1437 case SO_PEERCRED:
1438 {
1439 struct ucred peercred;
1440 if (len > sizeof(peercred))
1441 len = sizeof(peercred);
1442 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1443 if (copy_to_user(optval, &peercred, len))
1444 return -EFAULT;
1445 goto lenout;
1446 }
1447
1448 case SO_PEERGROUPS:
1449 {
1450 int ret, n;
1451
1452 if (!sk->sk_peer_cred)
1453 return -ENODATA;
1454
1455 n = sk->sk_peer_cred->group_info->ngroups;
1456 if (len < n * sizeof(gid_t)) {
1457 len = n * sizeof(gid_t);
1458 return put_user(len, optlen) ? -EFAULT : -ERANGE;
1459 }
1460 len = n * sizeof(gid_t);
1461
1462 ret = groups_to_user((gid_t __user *)optval,
1463 sk->sk_peer_cred->group_info);
1464 if (ret)
1465 return ret;
1466 goto lenout;
1467 }
1468
1469 case SO_PEERNAME:
1470 {
1471 char address[128];
1472
1473 lv = sock->ops->getname(sock, (struct sockaddr *)address, 2);
1474 if (lv < 0)
1475 return -ENOTCONN;
1476 if (lv < len)
1477 return -EINVAL;
1478 if (copy_to_user(optval, address, len))
1479 return -EFAULT;
1480 goto lenout;
1481 }
1482
1483 /* Dubious BSD thing... Probably nobody even uses it, but
1484 * the UNIX standard wants it for whatever reason... -DaveM
1485 */
1486 case SO_ACCEPTCONN:
1487 v.val = sk->sk_state == TCP_LISTEN;
1488 break;
1489
1490 case SO_PASSSEC:
1491 v.val = !!test_bit(SOCK_PASSSEC, &sock->flags);
1492 break;
1493
1494 case SO_PEERSEC:
1495 return security_socket_getpeersec_stream(sock, optval, optlen, len);
1496
1497 case SO_MARK:
1498 v.val = sk->sk_mark;
1499 break;
1500
1501 case SO_RXQ_OVFL:
1502 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
1503 break;
1504
1505 case SO_WIFI_STATUS:
1506 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
1507 break;
1508
1509 case SO_PEEK_OFF:
1510 if (!sock->ops->set_peek_off)
1511 return -EOPNOTSUPP;
1512
1513 v.val = sk->sk_peek_off;
1514 break;
1515 case SO_NOFCS:
1516 v.val = sock_flag(sk, SOCK_NOFCS);
1517 break;
1518
1519 case SO_BINDTODEVICE:
1520 return sock_getbindtodevice(sk, optval, optlen, len);
1521
1522 case SO_GET_FILTER:
1523 len = sk_get_filter(sk, (struct sock_filter __user *)optval, len);
1524 if (len < 0)
1525 return len;
1526
1527 goto lenout;
1528
1529 case SO_LOCK_FILTER:
1530 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
1531 break;
1532
1533 case SO_BPF_EXTENSIONS:
1534 v.val = bpf_tell_extensions();
1535 break;
1536
1537 case SO_SELECT_ERR_QUEUE:
1538 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
1539 break;
1540
1541#ifdef CONFIG_NET_RX_BUSY_POLL
1542 case SO_BUSY_POLL:
1543 v.val = sk->sk_ll_usec;
1544 break;
1545#endif
1546
1547 case SO_MAX_PACING_RATE:
1548 if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
1549 lv = sizeof(v.ulval);
1550 v.ulval = sk->sk_max_pacing_rate;
1551 } else {
1552 /* 32bit version */
1553 v.val = min_t(unsigned long, sk->sk_max_pacing_rate, ~0U);
1554 }
1555 break;
1556
1557 case SO_INCOMING_CPU:
1558 v.val = READ_ONCE(sk->sk_incoming_cpu);
1559 break;
1560
1561 case SO_MEMINFO:
1562 {
1563 u32 meminfo[SK_MEMINFO_VARS];
1564
1565 sk_get_meminfo(sk, meminfo);
1566
1567 len = min_t(unsigned int, len, sizeof(meminfo));
1568 if (copy_to_user(optval, &meminfo, len))
1569 return -EFAULT;
1570
1571 goto lenout;
1572 }
1573
1574#ifdef CONFIG_NET_RX_BUSY_POLL
1575 case SO_INCOMING_NAPI_ID:
1576 v.val = READ_ONCE(sk->sk_napi_id);
1577
1578 /* aggregate non-NAPI IDs down to 0 */
1579 if (v.val < MIN_NAPI_ID)
1580 v.val = 0;
1581
1582 break;
1583#endif
1584
1585 case SO_COOKIE:
1586 lv = sizeof(u64);
1587 if (len < lv)
1588 return -EINVAL;
1589 v.val64 = sock_gen_cookie(sk);
1590 break;
1591
1592 case SO_ZEROCOPY:
1593 v.val = sock_flag(sk, SOCK_ZEROCOPY);
1594 break;
1595
1596 case SO_TXTIME:
1597 lv = sizeof(v.txtime);
1598 v.txtime.clockid = sk->sk_clockid;
1599 v.txtime.flags |= sk->sk_txtime_deadline_mode ?
1600 SOF_TXTIME_DEADLINE_MODE : 0;
1601 v.txtime.flags |= sk->sk_txtime_report_errors ?
1602 SOF_TXTIME_REPORT_ERRORS : 0;
1603 break;
1604
1605 case SO_BINDTOIFINDEX:
1606 v.val = sk->sk_bound_dev_if;
1607 break;
1608
1609 default:
1610 /* We implement the SO_SNDLOWAT etc to not be settable
1611 * (1003.1g 7).
1612 */
1613 return -ENOPROTOOPT;
1614 }
1615
1616 if (len > lv)
1617 len = lv;
1618 if (copy_to_user(optval, &v, len))
1619 return -EFAULT;
1620lenout:
1621 if (put_user(len, optlen))
1622 return -EFAULT;
1623 return 0;
1624}
1625
1626/*
1627 * Initialize an sk_lock.
1628 *
1629 * (We also register the sk_lock with the lock validator.)
1630 */
1631static inline void sock_lock_init(struct sock *sk)
1632{
1633 if (sk->sk_kern_sock)
1634 sock_lock_init_class_and_name(
1635 sk,
1636 af_family_kern_slock_key_strings[sk->sk_family],
1637 af_family_kern_slock_keys + sk->sk_family,
1638 af_family_kern_key_strings[sk->sk_family],
1639 af_family_kern_keys + sk->sk_family);
1640 else
1641 sock_lock_init_class_and_name(
1642 sk,
1643 af_family_slock_key_strings[sk->sk_family],
1644 af_family_slock_keys + sk->sk_family,
1645 af_family_key_strings[sk->sk_family],
1646 af_family_keys + sk->sk_family);
1647}
1648
1649/*
1650 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
1651 * even temporarly, because of RCU lookups. sk_node should also be left as is.
1652 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
1653 */
1654static void sock_copy(struct sock *nsk, const struct sock *osk)
1655{
1656 const struct proto *prot = READ_ONCE(osk->sk_prot);
1657#ifdef CONFIG_SECURITY_NETWORK
1658 void *sptr = nsk->sk_security;
1659#endif
1660 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
1661
1662 memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
1663 prot->obj_size - offsetof(struct sock, sk_dontcopy_end));
1664
1665#ifdef CONFIG_SECURITY_NETWORK
1666 nsk->sk_security = sptr;
1667 security_sk_clone(osk, nsk);
1668#endif
1669}
1670
1671static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
1672 int family)
1673{
1674 struct sock *sk;
1675 struct kmem_cache *slab;
1676
1677 slab = prot->slab;
1678 if (slab != NULL) {
1679 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
1680 if (!sk)
1681 return sk;
1682 if (want_init_on_alloc(priority))
1683 sk_prot_clear_nulls(sk, prot->obj_size);
1684 } else
1685 sk = kmalloc(prot->obj_size, priority);
1686
1687 if (sk != NULL) {
1688 if (security_sk_alloc(sk, family, priority))
1689 goto out_free;
1690
1691 if (!try_module_get(prot->owner))
1692 goto out_free_sec;
1693 sk_tx_queue_clear(sk);
1694 }
1695
1696 return sk;
1697
1698out_free_sec:
1699 security_sk_free(sk);
1700out_free:
1701 if (slab != NULL)
1702 kmem_cache_free(slab, sk);
1703 else
1704 kfree(sk);
1705 return NULL;
1706}
1707
1708static void sk_prot_free(struct proto *prot, struct sock *sk)
1709{
1710 struct kmem_cache *slab;
1711 struct module *owner;
1712
1713 owner = prot->owner;
1714 slab = prot->slab;
1715
1716 cgroup_sk_free(&sk->sk_cgrp_data);
1717 mem_cgroup_sk_free(sk);
1718 security_sk_free(sk);
1719 if (slab != NULL)
1720 kmem_cache_free(slab, sk);
1721 else
1722 kfree(sk);
1723 module_put(owner);
1724}
1725
1726/**
1727 * sk_alloc - All socket objects are allocated here
1728 * @net: the applicable net namespace
1729 * @family: protocol family
1730 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1731 * @prot: struct proto associated with this new sock instance
1732 * @kern: is this to be a kernel socket?
1733 */
1734struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
1735 struct proto *prot, int kern)
1736{
1737 struct sock *sk;
1738
1739 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
1740 if (sk) {
1741 sk->sk_family = family;
1742 /*
1743 * See comment in struct sock definition to understand
1744 * why we need sk_prot_creator -acme
1745 */
1746 sk->sk_prot = sk->sk_prot_creator = prot;
1747 sk->sk_kern_sock = kern;
1748 sock_lock_init(sk);
1749 sk->sk_net_refcnt = kern ? 0 : 1;
1750 if (likely(sk->sk_net_refcnt)) {
1751 get_net(net);
1752 sock_inuse_add(net, 1);
1753 }
1754
1755 sock_net_set(sk, net);
1756 refcount_set(&sk->sk_wmem_alloc, 1);
1757
1758 mem_cgroup_sk_alloc(sk);
1759 cgroup_sk_alloc(&sk->sk_cgrp_data);
1760 sock_update_classid(&sk->sk_cgrp_data);
1761 sock_update_netprioidx(&sk->sk_cgrp_data);
1762 sk_tx_queue_clear(sk);
1763 }
1764
1765 return sk;
1766}
1767EXPORT_SYMBOL(sk_alloc);
1768
1769/* Sockets having SOCK_RCU_FREE will call this function after one RCU
1770 * grace period. This is the case for UDP sockets and TCP listeners.
1771 */
1772static void __sk_destruct(struct rcu_head *head)
1773{
1774 struct sock *sk = container_of(head, struct sock, sk_rcu);
1775 struct sk_filter *filter;
1776
1777 if (sk->sk_destruct)
1778 sk->sk_destruct(sk);
1779
1780 filter = rcu_dereference_check(sk->sk_filter,
1781 refcount_read(&sk->sk_wmem_alloc) == 0);
1782 if (filter) {
1783 sk_filter_uncharge(sk, filter);
1784 RCU_INIT_POINTER(sk->sk_filter, NULL);
1785 }
1786
1787 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
1788
1789#ifdef CONFIG_BPF_SYSCALL
1790 bpf_sk_storage_free(sk);
1791#endif
1792
1793 if (atomic_read(&sk->sk_omem_alloc))
1794 pr_debug("%s: optmem leakage (%d bytes) detected\n",
1795 __func__, atomic_read(&sk->sk_omem_alloc));
1796
1797 if (sk->sk_frag.page) {
1798 put_page(sk->sk_frag.page);
1799 sk->sk_frag.page = NULL;
1800 }
1801
1802 if (sk->sk_peer_cred)
1803 put_cred(sk->sk_peer_cred);
1804 put_pid(sk->sk_peer_pid);
1805 if (likely(sk->sk_net_refcnt))
1806 put_net(sock_net(sk));
1807 sk_prot_free(sk->sk_prot_creator, sk);
1808}
1809
1810void sk_destruct(struct sock *sk)
1811{
1812 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
1813
1814 if (rcu_access_pointer(sk->sk_reuseport_cb)) {
1815 reuseport_detach_sock(sk);
1816 use_call_rcu = true;
1817 }
1818
1819 if (use_call_rcu)
1820 call_rcu(&sk->sk_rcu, __sk_destruct);
1821 else
1822 __sk_destruct(&sk->sk_rcu);
1823}
1824
1825static void __sk_free(struct sock *sk)
1826{
1827 if (likely(sk->sk_net_refcnt))
1828 sock_inuse_add(sock_net(sk), -1);
1829
1830 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
1831 sock_diag_broadcast_destroy(sk);
1832 else
1833 sk_destruct(sk);
1834}
1835
1836void sk_free(struct sock *sk)
1837{
1838 /*
1839 * We subtract one from sk_wmem_alloc and can know if
1840 * some packets are still in some tx queue.
1841 * If not null, sock_wfree() will call __sk_free(sk) later
1842 */
1843 if (refcount_dec_and_test(&sk->sk_wmem_alloc))
1844 __sk_free(sk);
1845}
1846EXPORT_SYMBOL(sk_free);
1847
1848static void sk_init_common(struct sock *sk)
1849{
1850 skb_queue_head_init(&sk->sk_receive_queue);
1851 skb_queue_head_init(&sk->sk_write_queue);
1852 skb_queue_head_init(&sk->sk_error_queue);
1853
1854 rwlock_init(&sk->sk_callback_lock);
1855 lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
1856 af_rlock_keys + sk->sk_family,
1857 af_family_rlock_key_strings[sk->sk_family]);
1858 lockdep_set_class_and_name(&sk->sk_write_queue.lock,
1859 af_wlock_keys + sk->sk_family,
1860 af_family_wlock_key_strings[sk->sk_family]);
1861 lockdep_set_class_and_name(&sk->sk_error_queue.lock,
1862 af_elock_keys + sk->sk_family,
1863 af_family_elock_key_strings[sk->sk_family]);
1864 lockdep_set_class_and_name(&sk->sk_callback_lock,
1865 af_callback_keys + sk->sk_family,
1866 af_family_clock_key_strings[sk->sk_family]);
1867}
1868
1869/**
1870 * sk_clone_lock - clone a socket, and lock its clone
1871 * @sk: the socket to clone
1872 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
1873 *
1874 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
1875 */
1876struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
1877{
1878 struct proto *prot = READ_ONCE(sk->sk_prot);
1879 struct sock *newsk;
1880 bool is_charged = true;
1881
1882 newsk = sk_prot_alloc(prot, priority, sk->sk_family);
1883 if (newsk != NULL) {
1884 struct sk_filter *filter;
1885
1886 sock_copy(newsk, sk);
1887
1888 newsk->sk_prot_creator = prot;
1889
1890 /* SANITY */
1891 if (likely(newsk->sk_net_refcnt))
1892 get_net(sock_net(newsk));
1893 sk_node_init(&newsk->sk_node);
1894 sock_lock_init(newsk);
1895 bh_lock_sock(newsk);
1896 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
1897 newsk->sk_backlog.len = 0;
1898
1899 atomic_set(&newsk->sk_rmem_alloc, 0);
1900 /*
1901 * sk_wmem_alloc set to one (see sk_free() and sock_wfree())
1902 */
1903 refcount_set(&newsk->sk_wmem_alloc, 1);
1904 atomic_set(&newsk->sk_omem_alloc, 0);
1905 sk_init_common(newsk);
1906
1907 newsk->sk_dst_cache = NULL;
1908 newsk->sk_dst_pending_confirm = 0;
1909 newsk->sk_wmem_queued = 0;
1910 newsk->sk_forward_alloc = 0;
1911 atomic_set(&newsk->sk_drops, 0);
1912 newsk->sk_send_head = NULL;
1913 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
1914 atomic_set(&newsk->sk_zckey, 0);
1915
1916 sock_reset_flag(newsk, SOCK_DONE);
1917
1918 /* sk->sk_memcg will be populated at accept() time */
1919 newsk->sk_memcg = NULL;
1920
1921 cgroup_sk_clone(&newsk->sk_cgrp_data);
1922
1923 rcu_read_lock();
1924 filter = rcu_dereference(sk->sk_filter);
1925 if (filter != NULL)
1926 /* though it's an empty new sock, the charging may fail
1927 * if sysctl_optmem_max was changed between creation of
1928 * original socket and cloning
1929 */
1930 is_charged = sk_filter_charge(newsk, filter);
1931 RCU_INIT_POINTER(newsk->sk_filter, filter);
1932 rcu_read_unlock();
1933
1934 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
1935 /* We need to make sure that we don't uncharge the new
1936 * socket if we couldn't charge it in the first place
1937 * as otherwise we uncharge the parent's filter.
1938 */
1939 if (!is_charged)
1940 RCU_INIT_POINTER(newsk->sk_filter, NULL);
1941 sk_free_unlock_clone(newsk);
1942 newsk = NULL;
1943 goto out;
1944 }
1945 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
1946
1947 if (bpf_sk_storage_clone(sk, newsk)) {
1948 sk_free_unlock_clone(newsk);
1949 newsk = NULL;
1950 goto out;
1951 }
1952
1953 /* Clear sk_user_data if parent had the pointer tagged
1954 * as not suitable for copying when cloning.
1955 */
1956 if (sk_user_data_is_nocopy(newsk))
1957 newsk->sk_user_data = NULL;
1958
1959 newsk->sk_err = 0;
1960 newsk->sk_err_soft = 0;
1961 newsk->sk_priority = 0;
1962 newsk->sk_incoming_cpu = raw_smp_processor_id();
1963 if (likely(newsk->sk_net_refcnt))
1964 sock_inuse_add(sock_net(newsk), 1);
1965
1966 /*
1967 * Before updating sk_refcnt, we must commit prior changes to memory
1968 * (Documentation/RCU/rculist_nulls.rst for details)
1969 */
1970 smp_wmb();
1971 refcount_set(&newsk->sk_refcnt, 2);
1972
1973 /*
1974 * Increment the counter in the same struct proto as the master
1975 * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that
1976 * is the same as sk->sk_prot->socks, as this field was copied
1977 * with memcpy).
1978 *
1979 * This _changes_ the previous behaviour, where
1980 * tcp_create_openreq_child always was incrementing the
1981 * equivalent to tcp_prot->socks (inet_sock_nr), so this have
1982 * to be taken into account in all callers. -acme
1983 */
1984 sk_refcnt_debug_inc(newsk);
1985 sk_set_socket(newsk, NULL);
1986 sk_tx_queue_clear(newsk);
1987 RCU_INIT_POINTER(newsk->sk_wq, NULL);
1988
1989 if (newsk->sk_prot->sockets_allocated)
1990 sk_sockets_allocated_inc(newsk);
1991
1992 if (sock_needs_netstamp(sk) &&
1993 newsk->sk_flags & SK_FLAGS_TIMESTAMP)
1994 net_enable_timestamp();
1995 }
1996out:
1997 return newsk;
1998}
1999EXPORT_SYMBOL_GPL(sk_clone_lock);
2000
2001void sk_free_unlock_clone(struct sock *sk)
2002{
2003 /* It is still raw copy of parent, so invalidate
2004 * destructor and make plain sk_free() */
2005 sk->sk_destruct = NULL;
2006 bh_unlock_sock(sk);
2007 sk_free(sk);
2008}
2009EXPORT_SYMBOL_GPL(sk_free_unlock_clone);
2010
2011void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2012{
2013 u32 max_segs = 1;
2014
2015 sk_dst_set(sk, dst);
2016 sk->sk_route_caps = dst->dev->features | sk->sk_route_forced_caps;
2017 if (sk->sk_route_caps & NETIF_F_GSO)
2018 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2019 sk->sk_route_caps &= ~sk->sk_route_nocaps;
2020 if (sk_can_gso(sk)) {
2021 if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2022 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2023 } else {
2024 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2025 sk->sk_gso_max_size = dst->dev->gso_max_size;
2026 max_segs = max_t(u32, dst->dev->gso_max_segs, 1);
2027 }
2028 }
2029 sk->sk_gso_max_segs = max_segs;
2030}
2031EXPORT_SYMBOL_GPL(sk_setup_caps);
2032
2033/*
2034 * Simple resource managers for sockets.
2035 */
2036
2037
2038/*
2039 * Write buffer destructor automatically called from kfree_skb.
2040 */
2041void sock_wfree(struct sk_buff *skb)
2042{
2043 struct sock *sk = skb->sk;
2044 unsigned int len = skb->truesize;
2045
2046 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2047 /*
2048 * Keep a reference on sk_wmem_alloc, this will be released
2049 * after sk_write_space() call
2050 */
2051 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2052 sk->sk_write_space(sk);
2053 len = 1;
2054 }
2055 /*
2056 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2057 * could not do because of in-flight packets
2058 */
2059 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2060 __sk_free(sk);
2061}
2062EXPORT_SYMBOL(sock_wfree);
2063
2064/* This variant of sock_wfree() is used by TCP,
2065 * since it sets SOCK_USE_WRITE_QUEUE.
2066 */
2067void __sock_wfree(struct sk_buff *skb)
2068{
2069 struct sock *sk = skb->sk;
2070
2071 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2072 __sk_free(sk);
2073}
2074
2075void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2076{
2077 skb_orphan(skb);
2078 skb->sk = sk;
2079#ifdef CONFIG_INET
2080 if (unlikely(!sk_fullsock(sk))) {
2081 skb->destructor = sock_edemux;
2082 sock_hold(sk);
2083 return;
2084 }
2085#endif
2086 skb->destructor = sock_wfree;
2087 skb_set_hash_from_sk(skb, sk);
2088 /*
2089 * We used to take a refcount on sk, but following operation
2090 * is enough to guarantee sk_free() wont free this sock until
2091 * all in-flight packets are completed
2092 */
2093 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2094}
2095EXPORT_SYMBOL(skb_set_owner_w);
2096
2097static bool can_skb_orphan_partial(const struct sk_buff *skb)
2098{
2099#ifdef CONFIG_TLS_DEVICE
2100 /* Drivers depend on in-order delivery for crypto offload,
2101 * partial orphan breaks out-of-order-OK logic.
2102 */
2103 if (skb->decrypted)
2104 return false;
2105#endif
2106 return (skb->destructor == sock_wfree ||
2107 (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2108}
2109
2110/* This helper is used by netem, as it can hold packets in its
2111 * delay queue. We want to allow the owner socket to send more
2112 * packets, as if they were already TX completed by a typical driver.
2113 * But we also want to keep skb->sk set because some packet schedulers
2114 * rely on it (sch_fq for example).
2115 */
2116void skb_orphan_partial(struct sk_buff *skb)
2117{
2118 if (skb_is_tcp_pure_ack(skb))
2119 return;
2120
2121 if (can_skb_orphan_partial(skb)) {
2122 struct sock *sk = skb->sk;
2123
2124 if (refcount_inc_not_zero(&sk->sk_refcnt)) {
2125 WARN_ON(refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc));
2126 skb->destructor = sock_efree;
2127 }
2128 } else {
2129 skb_orphan(skb);
2130 }
2131}
2132EXPORT_SYMBOL(skb_orphan_partial);
2133
2134/*
2135 * Read buffer destructor automatically called from kfree_skb.
2136 */
2137void sock_rfree(struct sk_buff *skb)
2138{
2139 struct sock *sk = skb->sk;
2140 unsigned int len = skb->truesize;
2141
2142 atomic_sub(len, &sk->sk_rmem_alloc);
2143 sk_mem_uncharge(sk, len);
2144}
2145EXPORT_SYMBOL(sock_rfree);
2146
2147/*
2148 * Buffer destructor for skbs that are not used directly in read or write
2149 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2150 */
2151void sock_efree(struct sk_buff *skb)
2152{
2153 sock_put(skb->sk);
2154}
2155EXPORT_SYMBOL(sock_efree);
2156
2157/* Buffer destructor for prefetch/receive path where reference count may
2158 * not be held, e.g. for listen sockets.
2159 */
2160#ifdef CONFIG_INET
2161void sock_pfree(struct sk_buff *skb)
2162{
2163 if (sk_is_refcounted(skb->sk))
2164 sock_gen_put(skb->sk);
2165}
2166EXPORT_SYMBOL(sock_pfree);
2167#endif /* CONFIG_INET */
2168
2169kuid_t sock_i_uid(struct sock *sk)
2170{
2171 kuid_t uid;
2172
2173 read_lock_bh(&sk->sk_callback_lock);
2174 uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : GLOBAL_ROOT_UID;
2175 read_unlock_bh(&sk->sk_callback_lock);
2176 return uid;
2177}
2178EXPORT_SYMBOL(sock_i_uid);
2179
2180unsigned long sock_i_ino(struct sock *sk)
2181{
2182 unsigned long ino;
2183
2184 read_lock_bh(&sk->sk_callback_lock);
2185 ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0;
2186 read_unlock_bh(&sk->sk_callback_lock);
2187 return ino;
2188}
2189EXPORT_SYMBOL(sock_i_ino);
2190
2191/*
2192 * Allocate a skb from the socket's send buffer.
2193 */
2194struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2195 gfp_t priority)
2196{
2197 if (force ||
2198 refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2199 struct sk_buff *skb = alloc_skb(size, priority);
2200
2201 if (skb) {
2202 skb_set_owner_w(skb, sk);
2203 return skb;
2204 }
2205 }
2206 return NULL;
2207}
2208EXPORT_SYMBOL(sock_wmalloc);
2209
2210static void sock_ofree(struct sk_buff *skb)
2211{
2212 struct sock *sk = skb->sk;
2213
2214 atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2215}
2216
2217struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2218 gfp_t priority)
2219{
2220 struct sk_buff *skb;
2221
2222 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2223 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2224 sysctl_optmem_max)
2225 return NULL;
2226
2227 skb = alloc_skb(size, priority);
2228 if (!skb)
2229 return NULL;
2230
2231 atomic_add(skb->truesize, &sk->sk_omem_alloc);
2232 skb->sk = sk;
2233 skb->destructor = sock_ofree;
2234 return skb;
2235}
2236
2237/*
2238 * Allocate a memory block from the socket's option memory buffer.
2239 */
2240void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2241{
2242 if ((unsigned int)size <= sysctl_optmem_max &&
2243 atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) {
2244 void *mem;
2245 /* First do the add, to avoid the race if kmalloc
2246 * might sleep.
2247 */
2248 atomic_add(size, &sk->sk_omem_alloc);
2249 mem = kmalloc(size, priority);
2250 if (mem)
2251 return mem;
2252 atomic_sub(size, &sk->sk_omem_alloc);
2253 }
2254 return NULL;
2255}
2256EXPORT_SYMBOL(sock_kmalloc);
2257
2258/* Free an option memory block. Note, we actually want the inline
2259 * here as this allows gcc to detect the nullify and fold away the
2260 * condition entirely.
2261 */
2262static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2263 const bool nullify)
2264{
2265 if (WARN_ON_ONCE(!mem))
2266 return;
2267 if (nullify)
2268 kfree_sensitive(mem);
2269 else
2270 kfree(mem);
2271 atomic_sub(size, &sk->sk_omem_alloc);
2272}
2273
2274void sock_kfree_s(struct sock *sk, void *mem, int size)
2275{
2276 __sock_kfree_s(sk, mem, size, false);
2277}
2278EXPORT_SYMBOL(sock_kfree_s);
2279
2280void sock_kzfree_s(struct sock *sk, void *mem, int size)
2281{
2282 __sock_kfree_s(sk, mem, size, true);
2283}
2284EXPORT_SYMBOL(sock_kzfree_s);
2285
2286/* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2287 I think, these locks should be removed for datagram sockets.
2288 */
2289static long sock_wait_for_wmem(struct sock *sk, long timeo)
2290{
2291 DEFINE_WAIT(wait);
2292
2293 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2294 for (;;) {
2295 if (!timeo)
2296 break;
2297 if (signal_pending(current))
2298 break;
2299 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2300 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2301 if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2302 break;
2303 if (sk->sk_shutdown & SEND_SHUTDOWN)
2304 break;
2305 if (sk->sk_err)
2306 break;
2307 timeo = schedule_timeout(timeo);
2308 }
2309 finish_wait(sk_sleep(sk), &wait);
2310 return timeo;
2311}
2312
2313
2314/*
2315 * Generic send/receive buffer handlers
2316 */
2317
2318struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2319 unsigned long data_len, int noblock,
2320 int *errcode, int max_page_order)
2321{
2322 struct sk_buff *skb;
2323 long timeo;
2324 int err;
2325
2326 timeo = sock_sndtimeo(sk, noblock);
2327 for (;;) {
2328 err = sock_error(sk);
2329 if (err != 0)
2330 goto failure;
2331
2332 err = -EPIPE;
2333 if (sk->sk_shutdown & SEND_SHUTDOWN)
2334 goto failure;
2335
2336 if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2337 break;
2338
2339 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2340 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2341 err = -EAGAIN;
2342 if (!timeo)
2343 goto failure;
2344 if (signal_pending(current))
2345 goto interrupted;
2346 timeo = sock_wait_for_wmem(sk, timeo);
2347 }
2348 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2349 errcode, sk->sk_allocation);
2350 if (skb)
2351 skb_set_owner_w(skb, sk);
2352 return skb;
2353
2354interrupted:
2355 err = sock_intr_errno(timeo);
2356failure:
2357 *errcode = err;
2358 return NULL;
2359}
2360EXPORT_SYMBOL(sock_alloc_send_pskb);
2361
2362struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size,
2363 int noblock, int *errcode)
2364{
2365 return sock_alloc_send_pskb(sk, size, 0, noblock, errcode, 0);
2366}
2367EXPORT_SYMBOL(sock_alloc_send_skb);
2368
2369int __sock_cmsg_send(struct sock *sk, struct msghdr *msg, struct cmsghdr *cmsg,
2370 struct sockcm_cookie *sockc)
2371{
2372 u32 tsflags;
2373
2374 switch (cmsg->cmsg_type) {
2375 case SO_MARK:
2376 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2377 return -EPERM;
2378 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2379 return -EINVAL;
2380 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2381 break;
2382 case SO_TIMESTAMPING_OLD:
2383 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2384 return -EINVAL;
2385
2386 tsflags = *(u32 *)CMSG_DATA(cmsg);
2387 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
2388 return -EINVAL;
2389
2390 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
2391 sockc->tsflags |= tsflags;
2392 break;
2393 case SCM_TXTIME:
2394 if (!sock_flag(sk, SOCK_TXTIME))
2395 return -EINVAL;
2396 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
2397 return -EINVAL;
2398 sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
2399 break;
2400 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
2401 case SCM_RIGHTS:
2402 case SCM_CREDENTIALS:
2403 break;
2404 default:
2405 return -EINVAL;
2406 }
2407 return 0;
2408}
2409EXPORT_SYMBOL(__sock_cmsg_send);
2410
2411int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
2412 struct sockcm_cookie *sockc)
2413{
2414 struct cmsghdr *cmsg;
2415 int ret;
2416
2417 for_each_cmsghdr(cmsg, msg) {
2418 if (!CMSG_OK(msg, cmsg))
2419 return -EINVAL;
2420 if (cmsg->cmsg_level != SOL_SOCKET)
2421 continue;
2422 ret = __sock_cmsg_send(sk, msg, cmsg, sockc);
2423 if (ret)
2424 return ret;
2425 }
2426 return 0;
2427}
2428EXPORT_SYMBOL(sock_cmsg_send);
2429
2430static void sk_enter_memory_pressure(struct sock *sk)
2431{
2432 if (!sk->sk_prot->enter_memory_pressure)
2433 return;
2434
2435 sk->sk_prot->enter_memory_pressure(sk);
2436}
2437
2438static void sk_leave_memory_pressure(struct sock *sk)
2439{
2440 if (sk->sk_prot->leave_memory_pressure) {
2441 sk->sk_prot->leave_memory_pressure(sk);
2442 } else {
2443 unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
2444
2445 if (memory_pressure && READ_ONCE(*memory_pressure))
2446 WRITE_ONCE(*memory_pressure, 0);
2447 }
2448}
2449
2450#define SKB_FRAG_PAGE_ORDER get_order(32768)
2451DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
2452
2453/**
2454 * skb_page_frag_refill - check that a page_frag contains enough room
2455 * @sz: minimum size of the fragment we want to get
2456 * @pfrag: pointer to page_frag
2457 * @gfp: priority for memory allocation
2458 *
2459 * Note: While this allocator tries to use high order pages, there is
2460 * no guarantee that allocations succeed. Therefore, @sz MUST be
2461 * less or equal than PAGE_SIZE.
2462 */
2463bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
2464{
2465 if (pfrag->page) {
2466 if (page_ref_count(pfrag->page) == 1) {
2467 pfrag->offset = 0;
2468 return true;
2469 }
2470 if (pfrag->offset + sz <= pfrag->size)
2471 return true;
2472 put_page(pfrag->page);
2473 }
2474
2475 pfrag->offset = 0;
2476 if (SKB_FRAG_PAGE_ORDER &&
2477 !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
2478 /* Avoid direct reclaim but allow kswapd to wake */
2479 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
2480 __GFP_COMP | __GFP_NOWARN |
2481 __GFP_NORETRY,
2482 SKB_FRAG_PAGE_ORDER);
2483 if (likely(pfrag->page)) {
2484 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
2485 return true;
2486 }
2487 }
2488 pfrag->page = alloc_page(gfp);
2489 if (likely(pfrag->page)) {
2490 pfrag->size = PAGE_SIZE;
2491 return true;
2492 }
2493 return false;
2494}
2495EXPORT_SYMBOL(skb_page_frag_refill);
2496
2497bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
2498{
2499 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
2500 return true;
2501
2502 sk_enter_memory_pressure(sk);
2503 sk_stream_moderate_sndbuf(sk);
2504 return false;
2505}
2506EXPORT_SYMBOL(sk_page_frag_refill);
2507
2508static void __lock_sock(struct sock *sk)
2509 __releases(&sk->sk_lock.slock)
2510 __acquires(&sk->sk_lock.slock)
2511{
2512 DEFINE_WAIT(wait);
2513
2514 for (;;) {
2515 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
2516 TASK_UNINTERRUPTIBLE);
2517 spin_unlock_bh(&sk->sk_lock.slock);
2518 schedule();
2519 spin_lock_bh(&sk->sk_lock.slock);
2520 if (!sock_owned_by_user(sk))
2521 break;
2522 }
2523 finish_wait(&sk->sk_lock.wq, &wait);
2524}
2525
2526void __release_sock(struct sock *sk)
2527 __releases(&sk->sk_lock.slock)
2528 __acquires(&sk->sk_lock.slock)
2529{
2530 struct sk_buff *skb, *next;
2531
2532 while ((skb = sk->sk_backlog.head) != NULL) {
2533 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
2534
2535 spin_unlock_bh(&sk->sk_lock.slock);
2536
2537 do {
2538 next = skb->next;
2539 prefetch(next);
2540 WARN_ON_ONCE(skb_dst_is_noref(skb));
2541 skb_mark_not_on_list(skb);
2542 sk_backlog_rcv(sk, skb);
2543
2544 cond_resched();
2545
2546 skb = next;
2547 } while (skb != NULL);
2548
2549 spin_lock_bh(&sk->sk_lock.slock);
2550 }
2551
2552 /*
2553 * Doing the zeroing here guarantee we can not loop forever
2554 * while a wild producer attempts to flood us.
2555 */
2556 sk->sk_backlog.len = 0;
2557}
2558
2559void __sk_flush_backlog(struct sock *sk)
2560{
2561 spin_lock_bh(&sk->sk_lock.slock);
2562 __release_sock(sk);
2563 spin_unlock_bh(&sk->sk_lock.slock);
2564}
2565
2566/**
2567 * sk_wait_data - wait for data to arrive at sk_receive_queue
2568 * @sk: sock to wait on
2569 * @timeo: for how long
2570 * @skb: last skb seen on sk_receive_queue
2571 *
2572 * Now socket state including sk->sk_err is changed only under lock,
2573 * hence we may omit checks after joining wait queue.
2574 * We check receive queue before schedule() only as optimization;
2575 * it is very likely that release_sock() added new data.
2576 */
2577int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
2578{
2579 DEFINE_WAIT_FUNC(wait, woken_wake_function);
2580 int rc;
2581
2582 add_wait_queue(sk_sleep(sk), &wait);
2583 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2584 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
2585 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
2586 remove_wait_queue(sk_sleep(sk), &wait);
2587 return rc;
2588}
2589EXPORT_SYMBOL(sk_wait_data);
2590
2591/**
2592 * __sk_mem_raise_allocated - increase memory_allocated
2593 * @sk: socket
2594 * @size: memory size to allocate
2595 * @amt: pages to allocate
2596 * @kind: allocation type
2597 *
2598 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc
2599 */
2600int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
2601{
2602 struct proto *prot = sk->sk_prot;
2603 long allocated = sk_memory_allocated_add(sk, amt);
2604 bool charged = true;
2605
2606 if (mem_cgroup_sockets_enabled && sk->sk_memcg &&
2607 !(charged = mem_cgroup_charge_skmem(sk->sk_memcg, amt)))
2608 goto suppress_allocation;
2609
2610 /* Under limit. */
2611 if (allocated <= sk_prot_mem_limits(sk, 0)) {
2612 sk_leave_memory_pressure(sk);
2613 return 1;
2614 }
2615
2616 /* Under pressure. */
2617 if (allocated > sk_prot_mem_limits(sk, 1))
2618 sk_enter_memory_pressure(sk);
2619
2620 /* Over hard limit. */
2621 if (allocated > sk_prot_mem_limits(sk, 2))
2622 goto suppress_allocation;
2623
2624 /* guarantee minimum buffer size under pressure */
2625 if (kind == SK_MEM_RECV) {
2626 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
2627 return 1;
2628
2629 } else { /* SK_MEM_SEND */
2630 int wmem0 = sk_get_wmem0(sk, prot);
2631
2632 if (sk->sk_type == SOCK_STREAM) {
2633 if (sk->sk_wmem_queued < wmem0)
2634 return 1;
2635 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
2636 return 1;
2637 }
2638 }
2639
2640 if (sk_has_memory_pressure(sk)) {
2641 u64 alloc;
2642
2643 if (!sk_under_memory_pressure(sk))
2644 return 1;
2645 alloc = sk_sockets_allocated_read_positive(sk);
2646 if (sk_prot_mem_limits(sk, 2) > alloc *
2647 sk_mem_pages(sk->sk_wmem_queued +
2648 atomic_read(&sk->sk_rmem_alloc) +
2649 sk->sk_forward_alloc))
2650 return 1;
2651 }
2652
2653suppress_allocation:
2654
2655 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
2656 sk_stream_moderate_sndbuf(sk);
2657
2658 /* Fail only if socket is _under_ its sndbuf.
2659 * In this case we cannot block, so that we have to fail.
2660 */
2661 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf)
2662 return 1;
2663 }
2664
2665 if (kind == SK_MEM_SEND || (kind == SK_MEM_RECV && charged))
2666 trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
2667
2668 sk_memory_allocated_sub(sk, amt);
2669
2670 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2671 mem_cgroup_uncharge_skmem(sk->sk_memcg, amt);
2672
2673 return 0;
2674}
2675EXPORT_SYMBOL(__sk_mem_raise_allocated);
2676
2677/**
2678 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
2679 * @sk: socket
2680 * @size: memory size to allocate
2681 * @kind: allocation type
2682 *
2683 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
2684 * rmem allocation. This function assumes that protocols which have
2685 * memory_pressure use sk_wmem_queued as write buffer accounting.
2686 */
2687int __sk_mem_schedule(struct sock *sk, int size, int kind)
2688{
2689 int ret, amt = sk_mem_pages(size);
2690
2691 sk->sk_forward_alloc += amt << SK_MEM_QUANTUM_SHIFT;
2692 ret = __sk_mem_raise_allocated(sk, size, amt, kind);
2693 if (!ret)
2694 sk->sk_forward_alloc -= amt << SK_MEM_QUANTUM_SHIFT;
2695 return ret;
2696}
2697EXPORT_SYMBOL(__sk_mem_schedule);
2698
2699/**
2700 * __sk_mem_reduce_allocated - reclaim memory_allocated
2701 * @sk: socket
2702 * @amount: number of quanta
2703 *
2704 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
2705 */
2706void __sk_mem_reduce_allocated(struct sock *sk, int amount)
2707{
2708 sk_memory_allocated_sub(sk, amount);
2709
2710 if (mem_cgroup_sockets_enabled && sk->sk_memcg)
2711 mem_cgroup_uncharge_skmem(sk->sk_memcg, amount);
2712
2713 if (sk_under_memory_pressure(sk) &&
2714 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
2715 sk_leave_memory_pressure(sk);
2716}
2717EXPORT_SYMBOL(__sk_mem_reduce_allocated);
2718
2719/**
2720 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
2721 * @sk: socket
2722 * @amount: number of bytes (rounded down to a SK_MEM_QUANTUM multiple)
2723 */
2724void __sk_mem_reclaim(struct sock *sk, int amount)
2725{
2726 amount >>= SK_MEM_QUANTUM_SHIFT;
2727 sk->sk_forward_alloc -= amount << SK_MEM_QUANTUM_SHIFT;
2728 __sk_mem_reduce_allocated(sk, amount);
2729}
2730EXPORT_SYMBOL(__sk_mem_reclaim);
2731
2732int sk_set_peek_off(struct sock *sk, int val)
2733{
2734 sk->sk_peek_off = val;
2735 return 0;
2736}
2737EXPORT_SYMBOL_GPL(sk_set_peek_off);
2738
2739/*
2740 * Set of default routines for initialising struct proto_ops when
2741 * the protocol does not support a particular function. In certain
2742 * cases where it makes no sense for a protocol to have a "do nothing"
2743 * function, some default processing is provided.
2744 */
2745
2746int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
2747{
2748 return -EOPNOTSUPP;
2749}
2750EXPORT_SYMBOL(sock_no_bind);
2751
2752int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
2753 int len, int flags)
2754{
2755 return -EOPNOTSUPP;
2756}
2757EXPORT_SYMBOL(sock_no_connect);
2758
2759int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
2760{
2761 return -EOPNOTSUPP;
2762}
2763EXPORT_SYMBOL(sock_no_socketpair);
2764
2765int sock_no_accept(struct socket *sock, struct socket *newsock, int flags,
2766 bool kern)
2767{
2768 return -EOPNOTSUPP;
2769}
2770EXPORT_SYMBOL(sock_no_accept);
2771
2772int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
2773 int peer)
2774{
2775 return -EOPNOTSUPP;
2776}
2777EXPORT_SYMBOL(sock_no_getname);
2778
2779int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
2780{
2781 return -EOPNOTSUPP;
2782}
2783EXPORT_SYMBOL(sock_no_ioctl);
2784
2785int sock_no_listen(struct socket *sock, int backlog)
2786{
2787 return -EOPNOTSUPP;
2788}
2789EXPORT_SYMBOL(sock_no_listen);
2790
2791int sock_no_shutdown(struct socket *sock, int how)
2792{
2793 return -EOPNOTSUPP;
2794}
2795EXPORT_SYMBOL(sock_no_shutdown);
2796
2797int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
2798{
2799 return -EOPNOTSUPP;
2800}
2801EXPORT_SYMBOL(sock_no_sendmsg);
2802
2803int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
2804{
2805 return -EOPNOTSUPP;
2806}
2807EXPORT_SYMBOL(sock_no_sendmsg_locked);
2808
2809int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
2810 int flags)
2811{
2812 return -EOPNOTSUPP;
2813}
2814EXPORT_SYMBOL(sock_no_recvmsg);
2815
2816int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
2817{
2818 /* Mirror missing mmap method error code */
2819 return -ENODEV;
2820}
2821EXPORT_SYMBOL(sock_no_mmap);
2822
2823/*
2824 * When a file is received (via SCM_RIGHTS, etc), we must bump the
2825 * various sock-based usage counts.
2826 */
2827void __receive_sock(struct file *file)
2828{
2829 struct socket *sock;
2830 int error;
2831
2832 /*
2833 * The resulting value of "error" is ignored here since we only
2834 * need to take action when the file is a socket and testing
2835 * "sock" for NULL is sufficient.
2836 */
2837 sock = sock_from_file(file, &error);
2838 if (sock) {
2839 sock_update_netprioidx(&sock->sk->sk_cgrp_data);
2840 sock_update_classid(&sock->sk->sk_cgrp_data);
2841 }
2842}
2843
2844ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags)
2845{
2846 ssize_t res;
2847 struct msghdr msg = {.msg_flags = flags};
2848 struct kvec iov;
2849 char *kaddr = kmap(page);
2850 iov.iov_base = kaddr + offset;
2851 iov.iov_len = size;
2852 res = kernel_sendmsg(sock, &msg, &iov, 1, size);
2853 kunmap(page);
2854 return res;
2855}
2856EXPORT_SYMBOL(sock_no_sendpage);
2857
2858ssize_t sock_no_sendpage_locked(struct sock *sk, struct page *page,
2859 int offset, size_t size, int flags)
2860{
2861 ssize_t res;
2862 struct msghdr msg = {.msg_flags = flags};
2863 struct kvec iov;
2864 char *kaddr = kmap(page);
2865
2866 iov.iov_base = kaddr + offset;
2867 iov.iov_len = size;
2868 res = kernel_sendmsg_locked(sk, &msg, &iov, 1, size);
2869 kunmap(page);
2870 return res;
2871}
2872EXPORT_SYMBOL(sock_no_sendpage_locked);
2873
2874/*
2875 * Default Socket Callbacks
2876 */
2877
2878static void sock_def_wakeup(struct sock *sk)
2879{
2880 struct socket_wq *wq;
2881
2882 rcu_read_lock();
2883 wq = rcu_dereference(sk->sk_wq);
2884 if (skwq_has_sleeper(wq))
2885 wake_up_interruptible_all(&wq->wait);
2886 rcu_read_unlock();
2887}
2888
2889static void sock_def_error_report(struct sock *sk)
2890{
2891 struct socket_wq *wq;
2892
2893 rcu_read_lock();
2894 wq = rcu_dereference(sk->sk_wq);
2895 if (skwq_has_sleeper(wq))
2896 wake_up_interruptible_poll(&wq->wait, EPOLLERR);
2897 sk_wake_async(sk, SOCK_WAKE_IO, POLL_ERR);
2898 rcu_read_unlock();
2899}
2900
2901void sock_def_readable(struct sock *sk)
2902{
2903 struct socket_wq *wq;
2904
2905 rcu_read_lock();
2906 wq = rcu_dereference(sk->sk_wq);
2907 if (skwq_has_sleeper(wq))
2908 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
2909 EPOLLRDNORM | EPOLLRDBAND);
2910 sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
2911 rcu_read_unlock();
2912}
2913
2914static void sock_def_write_space(struct sock *sk)
2915{
2916 struct socket_wq *wq;
2917
2918 rcu_read_lock();
2919
2920 /* Do not wake up a writer until he can make "significant"
2921 * progress. --DaveM
2922 */
2923 if ((refcount_read(&sk->sk_wmem_alloc) << 1) <= READ_ONCE(sk->sk_sndbuf)) {
2924 wq = rcu_dereference(sk->sk_wq);
2925 if (skwq_has_sleeper(wq))
2926 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
2927 EPOLLWRNORM | EPOLLWRBAND);
2928
2929 /* Should agree with poll, otherwise some programs break */
2930 if (sock_writeable(sk))
2931 sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
2932 }
2933
2934 rcu_read_unlock();
2935}
2936
2937static void sock_def_destruct(struct sock *sk)
2938{
2939}
2940
2941void sk_send_sigurg(struct sock *sk)
2942{
2943 if (sk->sk_socket && sk->sk_socket->file)
2944 if (send_sigurg(&sk->sk_socket->file->f_owner))
2945 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
2946}
2947EXPORT_SYMBOL(sk_send_sigurg);
2948
2949void sk_reset_timer(struct sock *sk, struct timer_list* timer,
2950 unsigned long expires)
2951{
2952 if (!mod_timer(timer, expires))
2953 sock_hold(sk);
2954}
2955EXPORT_SYMBOL(sk_reset_timer);
2956
2957void sk_stop_timer(struct sock *sk, struct timer_list* timer)
2958{
2959 if (del_timer(timer))
2960 __sock_put(sk);
2961}
2962EXPORT_SYMBOL(sk_stop_timer);
2963
2964void sock_init_data(struct socket *sock, struct sock *sk)
2965{
2966 sk_init_common(sk);
2967 sk->sk_send_head = NULL;
2968
2969 timer_setup(&sk->sk_timer, NULL, 0);
2970
2971 sk->sk_allocation = GFP_KERNEL;
2972 sk->sk_rcvbuf = sysctl_rmem_default;
2973 sk->sk_sndbuf = sysctl_wmem_default;
2974 sk->sk_state = TCP_CLOSE;
2975 sk_set_socket(sk, sock);
2976
2977 sock_set_flag(sk, SOCK_ZAPPED);
2978
2979 if (sock) {
2980 sk->sk_type = sock->type;
2981 RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
2982 sock->sk = sk;
2983 sk->sk_uid = SOCK_INODE(sock)->i_uid;
2984 } else {
2985 RCU_INIT_POINTER(sk->sk_wq, NULL);
2986 sk->sk_uid = make_kuid(sock_net(sk)->user_ns, 0);
2987 }
2988
2989 rwlock_init(&sk->sk_callback_lock);
2990 if (sk->sk_kern_sock)
2991 lockdep_set_class_and_name(
2992 &sk->sk_callback_lock,
2993 af_kern_callback_keys + sk->sk_family,
2994 af_family_kern_clock_key_strings[sk->sk_family]);
2995 else
2996 lockdep_set_class_and_name(
2997 &sk->sk_callback_lock,
2998 af_callback_keys + sk->sk_family,
2999 af_family_clock_key_strings[sk->sk_family]);
3000
3001 sk->sk_state_change = sock_def_wakeup;
3002 sk->sk_data_ready = sock_def_readable;
3003 sk->sk_write_space = sock_def_write_space;
3004 sk->sk_error_report = sock_def_error_report;
3005 sk->sk_destruct = sock_def_destruct;
3006
3007 sk->sk_frag.page = NULL;
3008 sk->sk_frag.offset = 0;
3009 sk->sk_peek_off = -1;
3010
3011 sk->sk_peer_pid = NULL;
3012 sk->sk_peer_cred = NULL;
3013 sk->sk_write_pending = 0;
3014 sk->sk_rcvlowat = 1;
3015 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
3016 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
3017
3018 sk->sk_stamp = SK_DEFAULT_STAMP;
3019#if BITS_PER_LONG==32
3020 seqlock_init(&sk->sk_stamp_seq);
3021#endif
3022 atomic_set(&sk->sk_zckey, 0);
3023
3024#ifdef CONFIG_NET_RX_BUSY_POLL
3025 sk->sk_napi_id = 0;
3026 sk->sk_ll_usec = sysctl_net_busy_read;
3027#endif
3028
3029 sk->sk_max_pacing_rate = ~0UL;
3030 sk->sk_pacing_rate = ~0UL;
3031 WRITE_ONCE(sk->sk_pacing_shift, 10);
3032 sk->sk_incoming_cpu = -1;
3033
3034 sk_rx_queue_clear(sk);
3035 /*
3036 * Before updating sk_refcnt, we must commit prior changes to memory
3037 * (Documentation/RCU/rculist_nulls.rst for details)
3038 */
3039 smp_wmb();
3040 refcount_set(&sk->sk_refcnt, 1);
3041 atomic_set(&sk->sk_drops, 0);
3042}
3043EXPORT_SYMBOL(sock_init_data);
3044
3045void lock_sock_nested(struct sock *sk, int subclass)
3046{
3047 might_sleep();
3048 spin_lock_bh(&sk->sk_lock.slock);
3049 if (sk->sk_lock.owned)
3050 __lock_sock(sk);
3051 sk->sk_lock.owned = 1;
3052 spin_unlock(&sk->sk_lock.slock);
3053 /*
3054 * The sk_lock has mutex_lock() semantics here:
3055 */
3056 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3057 local_bh_enable();
3058}
3059EXPORT_SYMBOL(lock_sock_nested);
3060
3061void release_sock(struct sock *sk)
3062{
3063 spin_lock_bh(&sk->sk_lock.slock);
3064 if (sk->sk_backlog.tail)
3065 __release_sock(sk);
3066
3067 /* Warning : release_cb() might need to release sk ownership,
3068 * ie call sock_release_ownership(sk) before us.
3069 */
3070 if (sk->sk_prot->release_cb)
3071 sk->sk_prot->release_cb(sk);
3072
3073 sock_release_ownership(sk);
3074 if (waitqueue_active(&sk->sk_lock.wq))
3075 wake_up(&sk->sk_lock.wq);
3076 spin_unlock_bh(&sk->sk_lock.slock);
3077}
3078EXPORT_SYMBOL(release_sock);
3079
3080/**
3081 * lock_sock_fast - fast version of lock_sock
3082 * @sk: socket
3083 *
3084 * This version should be used for very small section, where process wont block
3085 * return false if fast path is taken:
3086 *
3087 * sk_lock.slock locked, owned = 0, BH disabled
3088 *
3089 * return true if slow path is taken:
3090 *
3091 * sk_lock.slock unlocked, owned = 1, BH enabled
3092 */
3093bool lock_sock_fast(struct sock *sk)
3094{
3095 might_sleep();
3096 spin_lock_bh(&sk->sk_lock.slock);
3097
3098 if (!sk->sk_lock.owned)
3099 /*
3100 * Note : We must disable BH
3101 */
3102 return false;
3103
3104 __lock_sock(sk);
3105 sk->sk_lock.owned = 1;
3106 spin_unlock(&sk->sk_lock.slock);
3107 /*
3108 * The sk_lock has mutex_lock() semantics here:
3109 */
3110 mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_);
3111 local_bh_enable();
3112 return true;
3113}
3114EXPORT_SYMBOL(lock_sock_fast);
3115
3116int sock_gettstamp(struct socket *sock, void __user *userstamp,
3117 bool timeval, bool time32)
3118{
3119 struct sock *sk = sock->sk;
3120 struct timespec64 ts;
3121
3122 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3123 ts = ktime_to_timespec64(sock_read_timestamp(sk));
3124 if (ts.tv_sec == -1)
3125 return -ENOENT;
3126 if (ts.tv_sec == 0) {
3127 ktime_t kt = ktime_get_real();
3128 sock_write_timestamp(sk, kt);
3129 ts = ktime_to_timespec64(kt);
3130 }
3131
3132 if (timeval)
3133 ts.tv_nsec /= 1000;
3134
3135#ifdef CONFIG_COMPAT_32BIT_TIME
3136 if (time32)
3137 return put_old_timespec32(&ts, userstamp);
3138#endif
3139#ifdef CONFIG_SPARC64
3140 /* beware of padding in sparc64 timeval */
3141 if (timeval && !in_compat_syscall()) {
3142 struct __kernel_old_timeval __user tv = {
3143 .tv_sec = ts.tv_sec,
3144 .tv_usec = ts.tv_nsec,
3145 };
3146 if (copy_to_user(userstamp, &tv, sizeof(tv)))
3147 return -EFAULT;
3148 return 0;
3149 }
3150#endif
3151 return put_timespec64(&ts, userstamp);
3152}
3153EXPORT_SYMBOL(sock_gettstamp);
3154
3155void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3156{
3157 if (!sock_flag(sk, flag)) {
3158 unsigned long previous_flags = sk->sk_flags;
3159
3160 sock_set_flag(sk, flag);
3161 /*
3162 * we just set one of the two flags which require net
3163 * time stamping, but time stamping might have been on
3164 * already because of the other one
3165 */
3166 if (sock_needs_netstamp(sk) &&
3167 !(previous_flags & SK_FLAGS_TIMESTAMP))
3168 net_enable_timestamp();
3169 }
3170}
3171
3172int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3173 int level, int type)
3174{
3175 struct sock_exterr_skb *serr;
3176 struct sk_buff *skb;
3177 int copied, err;
3178
3179 err = -EAGAIN;
3180 skb = sock_dequeue_err_skb(sk);
3181 if (skb == NULL)
3182 goto out;
3183
3184 copied = skb->len;
3185 if (copied > len) {
3186 msg->msg_flags |= MSG_TRUNC;
3187 copied = len;
3188 }
3189 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3190 if (err)
3191 goto out_free_skb;
3192
3193 sock_recv_timestamp(msg, sk, skb);
3194
3195 serr = SKB_EXT_ERR(skb);
3196 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3197
3198 msg->msg_flags |= MSG_ERRQUEUE;
3199 err = copied;
3200
3201out_free_skb:
3202 kfree_skb(skb);
3203out:
3204 return err;
3205}
3206EXPORT_SYMBOL(sock_recv_errqueue);
3207
3208/*
3209 * Get a socket option on an socket.
3210 *
3211 * FIX: POSIX 1003.1g is very ambiguous here. It states that
3212 * asynchronous errors should be reported by getsockopt. We assume
3213 * this means if you specify SO_ERROR (otherwise whats the point of it).
3214 */
3215int sock_common_getsockopt(struct socket *sock, int level, int optname,
3216 char __user *optval, int __user *optlen)
3217{
3218 struct sock *sk = sock->sk;
3219
3220 return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen);
3221}
3222EXPORT_SYMBOL(sock_common_getsockopt);
3223
3224int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3225 int flags)
3226{
3227 struct sock *sk = sock->sk;
3228 int addr_len = 0;
3229 int err;
3230
3231 err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
3232 flags & ~MSG_DONTWAIT, &addr_len);
3233 if (err >= 0)
3234 msg->msg_namelen = addr_len;
3235 return err;
3236}
3237EXPORT_SYMBOL(sock_common_recvmsg);
3238
3239/*
3240 * Set socket options on an inet socket.
3241 */
3242int sock_common_setsockopt(struct socket *sock, int level, int optname,
3243 sockptr_t optval, unsigned int optlen)
3244{
3245 struct sock *sk = sock->sk;
3246
3247 return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen);
3248}
3249EXPORT_SYMBOL(sock_common_setsockopt);
3250
3251void sk_common_release(struct sock *sk)
3252{
3253 if (sk->sk_prot->destroy)
3254 sk->sk_prot->destroy(sk);
3255
3256 /*
3257 * Observation: when sk_common_release is called, processes have
3258 * no access to socket. But net still has.
3259 * Step one, detach it from networking:
3260 *
3261 * A. Remove from hash tables.
3262 */
3263
3264 sk->sk_prot->unhash(sk);
3265
3266 /*
3267 * In this point socket cannot receive new packets, but it is possible
3268 * that some packets are in flight because some CPU runs receiver and
3269 * did hash table lookup before we unhashed socket. They will achieve
3270 * receive queue and will be purged by socket destructor.
3271 *
3272 * Also we still have packets pending on receive queue and probably,
3273 * our own packets waiting in device queues. sock_destroy will drain
3274 * receive queue, but transmitted packets will delay socket destruction
3275 * until the last reference will be released.
3276 */
3277
3278 sock_orphan(sk);
3279
3280 xfrm_sk_free_policy(sk);
3281
3282 sk_refcnt_debug_release(sk);
3283
3284 sock_put(sk);
3285}
3286EXPORT_SYMBOL(sk_common_release);
3287
3288void sk_get_meminfo(const struct sock *sk, u32 *mem)
3289{
3290 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3291
3292 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3293 mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3294 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3295 mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3296 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
3297 mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3298 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3299 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3300 mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops);
3301}
3302
3303#ifdef CONFIG_PROC_FS
3304#define PROTO_INUSE_NR 64 /* should be enough for the first time */
3305struct prot_inuse {
3306 int val[PROTO_INUSE_NR];
3307};
3308
3309static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3310
3311void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
3312{
3313 __this_cpu_add(net->core.prot_inuse->val[prot->inuse_idx], val);
3314}
3315EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
3316
3317int sock_prot_inuse_get(struct net *net, struct proto *prot)
3318{
3319 int cpu, idx = prot->inuse_idx;
3320 int res = 0;
3321
3322 for_each_possible_cpu(cpu)
3323 res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3324
3325 return res >= 0 ? res : 0;
3326}
3327EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3328
3329static void sock_inuse_add(struct net *net, int val)
3330{
3331 this_cpu_add(*net->core.sock_inuse, val);
3332}
3333
3334int sock_inuse_get(struct net *net)
3335{
3336 int cpu, res = 0;
3337
3338 for_each_possible_cpu(cpu)
3339 res += *per_cpu_ptr(net->core.sock_inuse, cpu);
3340
3341 return res;
3342}
3343
3344EXPORT_SYMBOL_GPL(sock_inuse_get);
3345
3346static int __net_init sock_inuse_init_net(struct net *net)
3347{
3348 net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3349 if (net->core.prot_inuse == NULL)
3350 return -ENOMEM;
3351
3352 net->core.sock_inuse = alloc_percpu(int);
3353 if (net->core.sock_inuse == NULL)
3354 goto out;
3355
3356 return 0;
3357
3358out:
3359 free_percpu(net->core.prot_inuse);
3360 return -ENOMEM;
3361}
3362
3363static void __net_exit sock_inuse_exit_net(struct net *net)
3364{
3365 free_percpu(net->core.prot_inuse);
3366 free_percpu(net->core.sock_inuse);
3367}
3368
3369static struct pernet_operations net_inuse_ops = {
3370 .init = sock_inuse_init_net,
3371 .exit = sock_inuse_exit_net,
3372};
3373
3374static __init int net_inuse_init(void)
3375{
3376 if (register_pernet_subsys(&net_inuse_ops))
3377 panic("Cannot initialize net inuse counters");
3378
3379 return 0;
3380}
3381
3382core_initcall(net_inuse_init);
3383
3384static int assign_proto_idx(struct proto *prot)
3385{
3386 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
3387
3388 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
3389 pr_err("PROTO_INUSE_NR exhausted\n");
3390 return -ENOSPC;
3391 }
3392
3393 set_bit(prot->inuse_idx, proto_inuse_idx);
3394 return 0;
3395}
3396
3397static void release_proto_idx(struct proto *prot)
3398{
3399 if (prot->inuse_idx != PROTO_INUSE_NR - 1)
3400 clear_bit(prot->inuse_idx, proto_inuse_idx);
3401}
3402#else
3403static inline int assign_proto_idx(struct proto *prot)
3404{
3405 return 0;
3406}
3407
3408static inline void release_proto_idx(struct proto *prot)
3409{
3410}
3411
3412static void sock_inuse_add(struct net *net, int val)
3413{
3414}
3415#endif
3416
3417static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
3418{
3419 if (!twsk_prot)
3420 return;
3421 kfree(twsk_prot->twsk_slab_name);
3422 twsk_prot->twsk_slab_name = NULL;
3423 kmem_cache_destroy(twsk_prot->twsk_slab);
3424 twsk_prot->twsk_slab = NULL;
3425}
3426
3427static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
3428{
3429 if (!rsk_prot)
3430 return;
3431 kfree(rsk_prot->slab_name);
3432 rsk_prot->slab_name = NULL;
3433 kmem_cache_destroy(rsk_prot->slab);
3434 rsk_prot->slab = NULL;
3435}
3436
3437static int req_prot_init(const struct proto *prot)
3438{
3439 struct request_sock_ops *rsk_prot = prot->rsk_prot;
3440
3441 if (!rsk_prot)
3442 return 0;
3443
3444 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
3445 prot->name);
3446 if (!rsk_prot->slab_name)
3447 return -ENOMEM;
3448
3449 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
3450 rsk_prot->obj_size, 0,
3451 SLAB_ACCOUNT | prot->slab_flags,
3452 NULL);
3453
3454 if (!rsk_prot->slab) {
3455 pr_crit("%s: Can't create request sock SLAB cache!\n",
3456 prot->name);
3457 return -ENOMEM;
3458 }
3459 return 0;
3460}
3461
3462int proto_register(struct proto *prot, int alloc_slab)
3463{
3464 int ret = -ENOBUFS;
3465
3466 if (alloc_slab) {
3467 prot->slab = kmem_cache_create_usercopy(prot->name,
3468 prot->obj_size, 0,
3469 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
3470 prot->slab_flags,
3471 prot->useroffset, prot->usersize,
3472 NULL);
3473
3474 if (prot->slab == NULL) {
3475 pr_crit("%s: Can't create sock SLAB cache!\n",
3476 prot->name);
3477 goto out;
3478 }
3479
3480 if (req_prot_init(prot))
3481 goto out_free_request_sock_slab;
3482
3483 if (prot->twsk_prot != NULL) {
3484 prot->twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s", prot->name);
3485
3486 if (prot->twsk_prot->twsk_slab_name == NULL)
3487 goto out_free_request_sock_slab;
3488
3489 prot->twsk_prot->twsk_slab =
3490 kmem_cache_create(prot->twsk_prot->twsk_slab_name,
3491 prot->twsk_prot->twsk_obj_size,
3492 0,
3493 SLAB_ACCOUNT |
3494 prot->slab_flags,
3495 NULL);
3496 if (prot->twsk_prot->twsk_slab == NULL)
3497 goto out_free_timewait_sock_slab;
3498 }
3499 }
3500
3501 mutex_lock(&proto_list_mutex);
3502 ret = assign_proto_idx(prot);
3503 if (ret) {
3504 mutex_unlock(&proto_list_mutex);
3505 goto out_free_timewait_sock_slab;
3506 }
3507 list_add(&prot->node, &proto_list);
3508 mutex_unlock(&proto_list_mutex);
3509 return ret;
3510
3511out_free_timewait_sock_slab:
3512 if (alloc_slab && prot->twsk_prot)
3513 tw_prot_cleanup(prot->twsk_prot);
3514out_free_request_sock_slab:
3515 if (alloc_slab) {
3516 req_prot_cleanup(prot->rsk_prot);
3517
3518 kmem_cache_destroy(prot->slab);
3519 prot->slab = NULL;
3520 }
3521out:
3522 return ret;
3523}
3524EXPORT_SYMBOL(proto_register);
3525
3526void proto_unregister(struct proto *prot)
3527{
3528 mutex_lock(&proto_list_mutex);
3529 release_proto_idx(prot);
3530 list_del(&prot->node);
3531 mutex_unlock(&proto_list_mutex);
3532
3533 kmem_cache_destroy(prot->slab);
3534 prot->slab = NULL;
3535
3536 req_prot_cleanup(prot->rsk_prot);
3537 tw_prot_cleanup(prot->twsk_prot);
3538}
3539EXPORT_SYMBOL(proto_unregister);
3540
3541int sock_load_diag_module(int family, int protocol)
3542{
3543 if (!protocol) {
3544 if (!sock_is_registered(family))
3545 return -ENOENT;
3546
3547 return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
3548 NETLINK_SOCK_DIAG, family);
3549 }
3550
3551#ifdef CONFIG_INET
3552 if (family == AF_INET &&
3553 protocol != IPPROTO_RAW &&
3554 protocol < MAX_INET_PROTOS &&
3555 !rcu_access_pointer(inet_protos[protocol]))
3556 return -ENOENT;
3557#endif
3558
3559 return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
3560 NETLINK_SOCK_DIAG, family, protocol);
3561}
3562EXPORT_SYMBOL(sock_load_diag_module);
3563
3564#ifdef CONFIG_PROC_FS
3565static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
3566 __acquires(proto_list_mutex)
3567{
3568 mutex_lock(&proto_list_mutex);
3569 return seq_list_start_head(&proto_list, *pos);
3570}
3571
3572static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3573{
3574 return seq_list_next(v, &proto_list, pos);
3575}
3576
3577static void proto_seq_stop(struct seq_file *seq, void *v)
3578 __releases(proto_list_mutex)
3579{
3580 mutex_unlock(&proto_list_mutex);
3581}
3582
3583static char proto_method_implemented(const void *method)
3584{
3585 return method == NULL ? 'n' : 'y';
3586}
3587static long sock_prot_memory_allocated(struct proto *proto)
3588{
3589 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
3590}
3591
3592static const char *sock_prot_memory_pressure(struct proto *proto)
3593{
3594 return proto->memory_pressure != NULL ?
3595 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
3596}
3597
3598static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
3599{
3600
3601 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
3602 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
3603 proto->name,
3604 proto->obj_size,
3605 sock_prot_inuse_get(seq_file_net(seq), proto),
3606 sock_prot_memory_allocated(proto),
3607 sock_prot_memory_pressure(proto),
3608 proto->max_header,
3609 proto->slab == NULL ? "no" : "yes",
3610 module_name(proto->owner),
3611 proto_method_implemented(proto->close),
3612 proto_method_implemented(proto->connect),
3613 proto_method_implemented(proto->disconnect),
3614 proto_method_implemented(proto->accept),
3615 proto_method_implemented(proto->ioctl),
3616 proto_method_implemented(proto->init),
3617 proto_method_implemented(proto->destroy),
3618 proto_method_implemented(proto->shutdown),
3619 proto_method_implemented(proto->setsockopt),
3620 proto_method_implemented(proto->getsockopt),
3621 proto_method_implemented(proto->sendmsg),
3622 proto_method_implemented(proto->recvmsg),
3623 proto_method_implemented(proto->sendpage),
3624 proto_method_implemented(proto->bind),
3625 proto_method_implemented(proto->backlog_rcv),
3626 proto_method_implemented(proto->hash),
3627 proto_method_implemented(proto->unhash),
3628 proto_method_implemented(proto->get_port),
3629 proto_method_implemented(proto->enter_memory_pressure));
3630}
3631
3632static int proto_seq_show(struct seq_file *seq, void *v)
3633{
3634 if (v == &proto_list)
3635 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
3636 "protocol",
3637 "size",
3638 "sockets",
3639 "memory",
3640 "press",
3641 "maxhdr",
3642 "slab",
3643 "module",
3644 "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n");
3645 else
3646 proto_seq_printf(seq, list_entry(v, struct proto, node));
3647 return 0;
3648}
3649
3650static const struct seq_operations proto_seq_ops = {
3651 .start = proto_seq_start,
3652 .next = proto_seq_next,
3653 .stop = proto_seq_stop,
3654 .show = proto_seq_show,
3655};
3656
3657static __net_init int proto_init_net(struct net *net)
3658{
3659 if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
3660 sizeof(struct seq_net_private)))
3661 return -ENOMEM;
3662
3663 return 0;
3664}
3665
3666static __net_exit void proto_exit_net(struct net *net)
3667{
3668 remove_proc_entry("protocols", net->proc_net);
3669}
3670
3671
3672static __net_initdata struct pernet_operations proto_net_ops = {
3673 .init = proto_init_net,
3674 .exit = proto_exit_net,
3675};
3676
3677static int __init proto_init(void)
3678{
3679 return register_pernet_subsys(&proto_net_ops);
3680}
3681
3682subsys_initcall(proto_init);
3683
3684#endif /* PROC_FS */
3685
3686#ifdef CONFIG_NET_RX_BUSY_POLL
3687bool sk_busy_loop_end(void *p, unsigned long start_time)
3688{
3689 struct sock *sk = p;
3690
3691 return !skb_queue_empty_lockless(&sk->sk_receive_queue) ||
3692 sk_busy_loop_timeout(sk, start_time);
3693}
3694EXPORT_SYMBOL(sk_busy_loop_end);
3695#endif /* CONFIG_NET_RX_BUSY_POLL */
3696
3697int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
3698{
3699 if (!sk->sk_prot->bind_add)
3700 return -EOPNOTSUPP;
3701 return sk->sk_prot->bind_add(sk, addr, addr_len);
3702}
3703EXPORT_SYMBOL(sock_bind_add);