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 <linux/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 <linux/skbuff_ref.h>
128 #include <net/net_namespace.h>
129 #include <net/request_sock.h>
130 #include <net/sock.h>
131 #include <net/proto_memory.h>
132 #include <linux/net_tstamp.h>
133 #include <net/xfrm.h>
134 #include <linux/ipsec.h>
135 #include <net/cls_cgroup.h>
136 #include <net/netprio_cgroup.h>
137 #include <linux/sock_diag.h>
138
139 #include <linux/filter.h>
140 #include <net/sock_reuseport.h>
141 #include <net/bpf_sk_storage.h>
142
143 #include <trace/events/sock.h>
144
145 #include <net/tcp.h>
146 #include <net/busy_poll.h>
147 #include <net/phonet/phonet.h>
148
149 #include <linux/ethtool.h>
150
151 #include <uapi/linux/pidfd.h>
152
153 #include "dev.h"
154
155 static DEFINE_MUTEX(proto_list_mutex);
156 static LIST_HEAD(proto_list);
157
158 static void sock_def_write_space_wfree(struct sock *sk);
159 static void sock_def_write_space(struct sock *sk);
160
161 /**
162 * sk_ns_capable - General socket capability test
163 * @sk: Socket to use a capability on or through
164 * @user_ns: The user namespace of the capability to use
165 * @cap: The capability to use
166 *
167 * Test to see if the opener of the socket had when the socket was
168 * created and the current process has the capability @cap in the user
169 * namespace @user_ns.
170 */
sk_ns_capable(const struct sock * sk,struct user_namespace * user_ns,int cap)171 bool sk_ns_capable(const struct sock *sk,
172 struct user_namespace *user_ns, int cap)
173 {
174 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
175 ns_capable(user_ns, cap);
176 }
177 EXPORT_SYMBOL(sk_ns_capable);
178
179 /**
180 * sk_capable - Socket global capability test
181 * @sk: Socket to use a capability on or through
182 * @cap: The global capability to use
183 *
184 * Test to see if the opener of the socket had when the socket was
185 * created and the current process has the capability @cap in all user
186 * namespaces.
187 */
sk_capable(const struct sock * sk,int cap)188 bool sk_capable(const struct sock *sk, int cap)
189 {
190 return sk_ns_capable(sk, &init_user_ns, cap);
191 }
192 EXPORT_SYMBOL(sk_capable);
193
194 /**
195 * sk_net_capable - Network namespace socket capability test
196 * @sk: Socket to use a capability on or through
197 * @cap: The capability to use
198 *
199 * Test to see if the opener of the socket had when the socket was created
200 * and the current process has the capability @cap over the network namespace
201 * the socket is a member of.
202 */
sk_net_capable(const struct sock * sk,int cap)203 bool sk_net_capable(const struct sock *sk, int cap)
204 {
205 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
206 }
207 EXPORT_SYMBOL(sk_net_capable);
208
209 /*
210 * Each address family might have different locking rules, so we have
211 * one slock key per address family and separate keys for internal and
212 * userspace sockets.
213 */
214 static struct lock_class_key af_family_keys[AF_MAX];
215 static struct lock_class_key af_family_kern_keys[AF_MAX];
216 static struct lock_class_key af_family_slock_keys[AF_MAX];
217 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
218
219 /*
220 * Make lock validator output more readable. (we pre-construct these
221 * strings build-time, so that runtime initialization of socket
222 * locks is fast):
223 */
224
225 #define _sock_locks(x) \
226 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \
227 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \
228 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \
229 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \
230 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \
231 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \
232 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \
233 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \
234 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \
235 x "27" , x "28" , x "AF_CAN" , \
236 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \
237 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \
238 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \
239 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \
240 x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \
241 x "AF_MCTP" , \
242 x "AF_MAX"
243
244 static const char *const af_family_key_strings[AF_MAX+1] = {
245 _sock_locks("sk_lock-")
246 };
247 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
248 _sock_locks("slock-")
249 };
250 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
251 _sock_locks("clock-")
252 };
253
254 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
255 _sock_locks("k-sk_lock-")
256 };
257 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
258 _sock_locks("k-slock-")
259 };
260 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
261 _sock_locks("k-clock-")
262 };
263 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
264 _sock_locks("rlock-")
265 };
266 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
267 _sock_locks("wlock-")
268 };
269 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
270 _sock_locks("elock-")
271 };
272
273 /*
274 * sk_callback_lock and sk queues locking rules are per-address-family,
275 * so split the lock classes by using a per-AF key:
276 */
277 static struct lock_class_key af_callback_keys[AF_MAX];
278 static struct lock_class_key af_rlock_keys[AF_MAX];
279 static struct lock_class_key af_wlock_keys[AF_MAX];
280 static struct lock_class_key af_elock_keys[AF_MAX];
281 static struct lock_class_key af_kern_callback_keys[AF_MAX];
282
283 /* Run time adjustable parameters. */
284 __u32 sysctl_wmem_max __read_mostly = 4 << 20;
285 EXPORT_SYMBOL(sysctl_wmem_max);
286 __u32 sysctl_rmem_max __read_mostly = 4 << 20;
287 EXPORT_SYMBOL(sysctl_rmem_max);
288 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_DEFAULT;
289 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_DEFAULT;
290
291 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
292 EXPORT_SYMBOL_GPL(memalloc_socks_key);
293
294 /**
295 * sk_set_memalloc - sets %SOCK_MEMALLOC
296 * @sk: socket to set it on
297 *
298 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
299 * It's the responsibility of the admin to adjust min_free_kbytes
300 * to meet the requirements
301 */
sk_set_memalloc(struct sock * sk)302 void sk_set_memalloc(struct sock *sk)
303 {
304 sock_set_flag(sk, SOCK_MEMALLOC);
305 sk->sk_allocation |= __GFP_MEMALLOC;
306 static_branch_inc(&memalloc_socks_key);
307 }
308 EXPORT_SYMBOL_GPL(sk_set_memalloc);
309
sk_clear_memalloc(struct sock * sk)310 void sk_clear_memalloc(struct sock *sk)
311 {
312 sock_reset_flag(sk, SOCK_MEMALLOC);
313 sk->sk_allocation &= ~__GFP_MEMALLOC;
314 static_branch_dec(&memalloc_socks_key);
315
316 /*
317 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
318 * progress of swapping. SOCK_MEMALLOC may be cleared while
319 * it has rmem allocations due to the last swapfile being deactivated
320 * but there is a risk that the socket is unusable due to exceeding
321 * the rmem limits. Reclaim the reserves and obey rmem limits again.
322 */
323 sk_mem_reclaim(sk);
324 }
325 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
326
__sk_backlog_rcv(struct sock * sk,struct sk_buff * skb)327 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
328 {
329 int ret;
330 unsigned int noreclaim_flag;
331
332 /* these should have been dropped before queueing */
333 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
334
335 noreclaim_flag = memalloc_noreclaim_save();
336 ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
337 tcp_v6_do_rcv,
338 tcp_v4_do_rcv,
339 sk, skb);
340 memalloc_noreclaim_restore(noreclaim_flag);
341
342 return ret;
343 }
344 EXPORT_SYMBOL(__sk_backlog_rcv);
345
sk_error_report(struct sock * sk)346 void sk_error_report(struct sock *sk)
347 {
348 sk->sk_error_report(sk);
349
350 switch (sk->sk_family) {
351 case AF_INET:
352 fallthrough;
353 case AF_INET6:
354 trace_inet_sk_error_report(sk);
355 break;
356 default:
357 break;
358 }
359 }
360 EXPORT_SYMBOL(sk_error_report);
361
sock_get_timeout(long timeo,void * optval,bool old_timeval)362 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
363 {
364 struct __kernel_sock_timeval tv;
365
366 if (timeo == MAX_SCHEDULE_TIMEOUT) {
367 tv.tv_sec = 0;
368 tv.tv_usec = 0;
369 } else {
370 tv.tv_sec = timeo / HZ;
371 tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
372 }
373
374 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
375 struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
376 *(struct old_timeval32 *)optval = tv32;
377 return sizeof(tv32);
378 }
379
380 if (old_timeval) {
381 struct __kernel_old_timeval old_tv;
382 old_tv.tv_sec = tv.tv_sec;
383 old_tv.tv_usec = tv.tv_usec;
384 *(struct __kernel_old_timeval *)optval = old_tv;
385 return sizeof(old_tv);
386 }
387
388 *(struct __kernel_sock_timeval *)optval = tv;
389 return sizeof(tv);
390 }
391 EXPORT_SYMBOL(sock_get_timeout);
392
sock_copy_user_timeval(struct __kernel_sock_timeval * tv,sockptr_t optval,int optlen,bool old_timeval)393 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
394 sockptr_t optval, int optlen, bool old_timeval)
395 {
396 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
397 struct old_timeval32 tv32;
398
399 if (optlen < sizeof(tv32))
400 return -EINVAL;
401
402 if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
403 return -EFAULT;
404 tv->tv_sec = tv32.tv_sec;
405 tv->tv_usec = tv32.tv_usec;
406 } else if (old_timeval) {
407 struct __kernel_old_timeval old_tv;
408
409 if (optlen < sizeof(old_tv))
410 return -EINVAL;
411 if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
412 return -EFAULT;
413 tv->tv_sec = old_tv.tv_sec;
414 tv->tv_usec = old_tv.tv_usec;
415 } else {
416 if (optlen < sizeof(*tv))
417 return -EINVAL;
418 if (copy_from_sockptr(tv, optval, sizeof(*tv)))
419 return -EFAULT;
420 }
421
422 return 0;
423 }
424 EXPORT_SYMBOL(sock_copy_user_timeval);
425
sock_set_timeout(long * timeo_p,sockptr_t optval,int optlen,bool old_timeval)426 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
427 bool old_timeval)
428 {
429 struct __kernel_sock_timeval tv;
430 int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
431 long val;
432
433 if (err)
434 return err;
435
436 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
437 return -EDOM;
438
439 if (tv.tv_sec < 0) {
440 static int warned __read_mostly;
441
442 WRITE_ONCE(*timeo_p, 0);
443 if (warned < 10 && net_ratelimit()) {
444 warned++;
445 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
446 __func__, current->comm, task_pid_nr(current));
447 }
448 return 0;
449 }
450 val = MAX_SCHEDULE_TIMEOUT;
451 if ((tv.tv_sec || tv.tv_usec) &&
452 (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))
453 val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,
454 USEC_PER_SEC / HZ);
455 WRITE_ONCE(*timeo_p, val);
456 return 0;
457 }
458
sk_set_prio_allowed(const struct sock * sk,int val)459 static bool sk_set_prio_allowed(const struct sock *sk, int val)
460 {
461 return ((val >= TC_PRIO_BESTEFFORT && val <= TC_PRIO_INTERACTIVE) ||
462 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
463 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN));
464 }
465
sock_needs_netstamp(const struct sock * sk)466 static bool sock_needs_netstamp(const struct sock *sk)
467 {
468 switch (sk->sk_family) {
469 case AF_UNSPEC:
470 case AF_UNIX:
471 return false;
472 default:
473 return true;
474 }
475 }
476
sock_disable_timestamp(struct sock * sk,unsigned long flags)477 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
478 {
479 if (sk->sk_flags & flags) {
480 sk->sk_flags &= ~flags;
481 if (sock_needs_netstamp(sk) &&
482 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
483 net_disable_timestamp();
484 }
485 }
486
487
__sock_queue_rcv_skb(struct sock * sk,struct sk_buff * skb)488 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
489 {
490 unsigned long flags;
491 struct sk_buff_head *list = &sk->sk_receive_queue;
492
493 if (atomic_read(&sk->sk_rmem_alloc) >= READ_ONCE(sk->sk_rcvbuf)) {
494 sk_drops_inc(sk);
495 trace_sock_rcvqueue_full(sk, skb);
496 return -ENOMEM;
497 }
498
499 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
500 sk_drops_inc(sk);
501 return -ENOBUFS;
502 }
503
504 skb->dev = NULL;
505 skb_set_owner_r(skb, sk);
506
507 /* we escape from rcu protected region, make sure we dont leak
508 * a norefcounted dst
509 */
510 skb_dst_force(skb);
511
512 spin_lock_irqsave(&list->lock, flags);
513 sock_skb_set_dropcount(sk, skb);
514 __skb_queue_tail(list, skb);
515 spin_unlock_irqrestore(&list->lock, flags);
516
517 if (!sock_flag(sk, SOCK_DEAD))
518 sk->sk_data_ready(sk);
519 return 0;
520 }
521 EXPORT_SYMBOL(__sock_queue_rcv_skb);
522
sock_queue_rcv_skb_reason(struct sock * sk,struct sk_buff * skb,enum skb_drop_reason * reason)523 int sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb,
524 enum skb_drop_reason *reason)
525 {
526 enum skb_drop_reason drop_reason;
527 int err;
528
529 err = sk_filter_reason(sk, skb, &drop_reason);
530 if (err)
531 goto out;
532
533 err = __sock_queue_rcv_skb(sk, skb);
534 switch (err) {
535 case -ENOMEM:
536 drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
537 break;
538 case -ENOBUFS:
539 drop_reason = SKB_DROP_REASON_PROTO_MEM;
540 break;
541 default:
542 drop_reason = SKB_NOT_DROPPED_YET;
543 break;
544 }
545 out:
546 if (reason)
547 *reason = drop_reason;
548 return err;
549 }
550 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
551
__sk_receive_skb(struct sock * sk,struct sk_buff * skb,const int nested,unsigned int trim_cap,bool refcounted)552 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
553 const int nested, unsigned int trim_cap, bool refcounted)
554 {
555 enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED;
556 int rc = NET_RX_SUCCESS;
557 int err;
558
559 if (sk_filter_trim_cap(sk, skb, trim_cap, &reason))
560 goto discard_and_relse;
561
562 skb->dev = NULL;
563
564 if (sk_rcvqueues_full(sk, READ_ONCE(sk->sk_rcvbuf))) {
565 sk_drops_inc(sk);
566 reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
567 goto discard_and_relse;
568 }
569 if (nested)
570 bh_lock_sock_nested(sk);
571 else
572 bh_lock_sock(sk);
573 if (!sock_owned_by_user(sk)) {
574 /*
575 * trylock + unlock semantics:
576 */
577 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
578
579 rc = sk_backlog_rcv(sk, skb);
580
581 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
582 } else if ((err = sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf)))) {
583 bh_unlock_sock(sk);
584 if (err == -ENOMEM)
585 reason = SKB_DROP_REASON_PFMEMALLOC;
586 if (err == -ENOBUFS)
587 reason = SKB_DROP_REASON_SOCKET_BACKLOG;
588 sk_drops_inc(sk);
589 goto discard_and_relse;
590 }
591
592 bh_unlock_sock(sk);
593 out:
594 if (refcounted)
595 sock_put(sk);
596 return rc;
597 discard_and_relse:
598 sk_skb_reason_drop(sk, skb, reason);
599 goto out;
600 }
601 EXPORT_SYMBOL(__sk_receive_skb);
602
603 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
604 u32));
605 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
606 u32));
__sk_dst_check(struct sock * sk,u32 cookie)607 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
608 {
609 struct dst_entry *dst = __sk_dst_get(sk);
610
611 if (dst && READ_ONCE(dst->obsolete) &&
612 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
613 dst, cookie) == NULL) {
614 sk_tx_queue_clear(sk);
615 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
616 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
617 dst_release(dst);
618 return NULL;
619 }
620
621 return dst;
622 }
623 EXPORT_SYMBOL(__sk_dst_check);
624
sk_dst_check(struct sock * sk,u32 cookie)625 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
626 {
627 struct dst_entry *dst = sk_dst_get(sk);
628
629 if (dst && READ_ONCE(dst->obsolete) &&
630 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
631 dst, cookie) == NULL) {
632 sk_dst_reset(sk);
633 dst_release(dst);
634 return NULL;
635 }
636
637 return dst;
638 }
639 EXPORT_SYMBOL(sk_dst_check);
640
sock_bindtoindex_locked(struct sock * sk,int ifindex)641 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
642 {
643 int ret = -ENOPROTOOPT;
644 #ifdef CONFIG_NETDEVICES
645 struct net *net = sock_net(sk);
646
647 /* Sorry... */
648 ret = -EPERM;
649 if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
650 goto out;
651
652 ret = -EINVAL;
653 if (ifindex < 0)
654 goto out;
655
656 /* Paired with all READ_ONCE() done locklessly. */
657 WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
658
659 if (sk->sk_prot->rehash)
660 sk->sk_prot->rehash(sk);
661 sk_dst_reset(sk);
662
663 ret = 0;
664
665 out:
666 #endif
667
668 return ret;
669 }
670
sock_bindtoindex(struct sock * sk,int ifindex,bool lock_sk)671 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
672 {
673 int ret;
674
675 if (lock_sk)
676 lock_sock(sk);
677 ret = sock_bindtoindex_locked(sk, ifindex);
678 if (lock_sk)
679 release_sock(sk);
680
681 return ret;
682 }
683 EXPORT_SYMBOL(sock_bindtoindex);
684
sock_setbindtodevice(struct sock * sk,sockptr_t optval,int optlen)685 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
686 {
687 int ret = -ENOPROTOOPT;
688 #ifdef CONFIG_NETDEVICES
689 struct net *net = sock_net(sk);
690 char devname[IFNAMSIZ];
691 int index;
692
693 ret = -EINVAL;
694 if (optlen < 0)
695 goto out;
696
697 /* Bind this socket to a particular device like "eth0",
698 * as specified in the passed interface name. If the
699 * name is "" or the option length is zero the socket
700 * is not bound.
701 */
702 if (optlen > IFNAMSIZ - 1)
703 optlen = IFNAMSIZ - 1;
704 memset(devname, 0, sizeof(devname));
705
706 ret = -EFAULT;
707 if (copy_from_sockptr(devname, optval, optlen))
708 goto out;
709
710 index = 0;
711 if (devname[0] != '\0') {
712 struct net_device *dev;
713
714 rcu_read_lock();
715 dev = dev_get_by_name_rcu(net, devname);
716 if (dev)
717 index = dev->ifindex;
718 rcu_read_unlock();
719 ret = -ENODEV;
720 if (!dev)
721 goto out;
722 }
723
724 sockopt_lock_sock(sk);
725 ret = sock_bindtoindex_locked(sk, index);
726 sockopt_release_sock(sk);
727 out:
728 #endif
729
730 return ret;
731 }
732
sock_getbindtodevice(struct sock * sk,sockptr_t optval,sockptr_t optlen,int len)733 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
734 sockptr_t optlen, int len)
735 {
736 int ret = -ENOPROTOOPT;
737 #ifdef CONFIG_NETDEVICES
738 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
739 struct net *net = sock_net(sk);
740 char devname[IFNAMSIZ];
741
742 if (bound_dev_if == 0) {
743 len = 0;
744 goto zero;
745 }
746
747 ret = -EINVAL;
748 if (len < IFNAMSIZ)
749 goto out;
750
751 ret = netdev_get_name(net, devname, bound_dev_if);
752 if (ret)
753 goto out;
754
755 len = strlen(devname) + 1;
756
757 ret = -EFAULT;
758 if (copy_to_sockptr(optval, devname, len))
759 goto out;
760
761 zero:
762 ret = -EFAULT;
763 if (copy_to_sockptr(optlen, &len, sizeof(int)))
764 goto out;
765
766 ret = 0;
767
768 out:
769 #endif
770
771 return ret;
772 }
773
sk_mc_loop(const struct sock * sk)774 bool sk_mc_loop(const struct sock *sk)
775 {
776 if (dev_recursion_level())
777 return false;
778 if (!sk)
779 return true;
780 /* IPV6_ADDRFORM can change sk->sk_family under us. */
781 switch (READ_ONCE(sk->sk_family)) {
782 case AF_INET:
783 return inet_test_bit(MC_LOOP, sk);
784 #if IS_ENABLED(CONFIG_IPV6)
785 case AF_INET6:
786 return inet6_test_bit(MC6_LOOP, sk);
787 #endif
788 }
789 WARN_ON_ONCE(1);
790 return true;
791 }
792 EXPORT_SYMBOL(sk_mc_loop);
793
sock_set_reuseaddr(struct sock * sk)794 void sock_set_reuseaddr(struct sock *sk)
795 {
796 lock_sock(sk);
797 sk->sk_reuse = SK_CAN_REUSE;
798 release_sock(sk);
799 }
800 EXPORT_SYMBOL(sock_set_reuseaddr);
801
sock_set_reuseport(struct sock * sk)802 void sock_set_reuseport(struct sock *sk)
803 {
804 lock_sock(sk);
805 sk->sk_reuseport = true;
806 release_sock(sk);
807 }
808 EXPORT_SYMBOL(sock_set_reuseport);
809
sock_no_linger(struct sock * sk)810 void sock_no_linger(struct sock *sk)
811 {
812 lock_sock(sk);
813 WRITE_ONCE(sk->sk_lingertime, 0);
814 sock_set_flag(sk, SOCK_LINGER);
815 release_sock(sk);
816 }
817 EXPORT_SYMBOL(sock_no_linger);
818
sock_set_priority(struct sock * sk,u32 priority)819 void sock_set_priority(struct sock *sk, u32 priority)
820 {
821 WRITE_ONCE(sk->sk_priority, priority);
822 }
823 EXPORT_SYMBOL(sock_set_priority);
824
sock_set_sndtimeo(struct sock * sk,s64 secs)825 void sock_set_sndtimeo(struct sock *sk, s64 secs)
826 {
827 if (secs && secs < MAX_SCHEDULE_TIMEOUT / HZ - 1)
828 WRITE_ONCE(sk->sk_sndtimeo, secs * HZ);
829 else
830 WRITE_ONCE(sk->sk_sndtimeo, MAX_SCHEDULE_TIMEOUT);
831 }
832 EXPORT_SYMBOL(sock_set_sndtimeo);
833
__sock_set_timestamps(struct sock * sk,bool val,bool new,bool ns)834 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
835 {
836 sock_valbool_flag(sk, SOCK_RCVTSTAMP, val);
837 sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, val && ns);
838 if (val) {
839 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
840 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
841 }
842 }
843
sock_set_timestamp(struct sock * sk,int optname,bool valbool)844 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
845 {
846 switch (optname) {
847 case SO_TIMESTAMP_OLD:
848 __sock_set_timestamps(sk, valbool, false, false);
849 break;
850 case SO_TIMESTAMP_NEW:
851 __sock_set_timestamps(sk, valbool, true, false);
852 break;
853 case SO_TIMESTAMPNS_OLD:
854 __sock_set_timestamps(sk, valbool, false, true);
855 break;
856 case SO_TIMESTAMPNS_NEW:
857 __sock_set_timestamps(sk, valbool, true, true);
858 break;
859 }
860 }
861
sock_timestamping_bind_phc(struct sock * sk,int phc_index)862 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
863 {
864 struct net *net = sock_net(sk);
865 struct net_device *dev = NULL;
866 bool match = false;
867 int *vclock_index;
868 int i, num;
869
870 if (sk->sk_bound_dev_if)
871 dev = dev_get_by_index(net, sk->sk_bound_dev_if);
872
873 if (!dev) {
874 pr_err("%s: sock not bind to device\n", __func__);
875 return -EOPNOTSUPP;
876 }
877
878 num = ethtool_get_phc_vclocks(dev, &vclock_index);
879 dev_put(dev);
880
881 for (i = 0; i < num; i++) {
882 if (*(vclock_index + i) == phc_index) {
883 match = true;
884 break;
885 }
886 }
887
888 if (num > 0)
889 kfree(vclock_index);
890
891 if (!match)
892 return -EINVAL;
893
894 WRITE_ONCE(sk->sk_bind_phc, phc_index);
895
896 return 0;
897 }
898
sock_set_timestamping(struct sock * sk,int optname,struct so_timestamping timestamping)899 int sock_set_timestamping(struct sock *sk, int optname,
900 struct so_timestamping timestamping)
901 {
902 int val = timestamping.flags;
903 int ret;
904
905 if (val & ~SOF_TIMESTAMPING_MASK)
906 return -EINVAL;
907
908 if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
909 !(val & SOF_TIMESTAMPING_OPT_ID))
910 return -EINVAL;
911
912 if (val & SOF_TIMESTAMPING_OPT_ID &&
913 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
914 if (sk_is_tcp(sk)) {
915 if ((1 << sk->sk_state) &
916 (TCPF_CLOSE | TCPF_LISTEN))
917 return -EINVAL;
918 if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
919 atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
920 else
921 atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
922 } else {
923 atomic_set(&sk->sk_tskey, 0);
924 }
925 }
926
927 if (val & SOF_TIMESTAMPING_OPT_STATS &&
928 !(val & SOF_TIMESTAMPING_OPT_TSONLY))
929 return -EINVAL;
930
931 if (val & SOF_TIMESTAMPING_BIND_PHC) {
932 ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
933 if (ret)
934 return ret;
935 }
936
937 WRITE_ONCE(sk->sk_tsflags, val);
938 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
939 sock_valbool_flag(sk, SOCK_TIMESTAMPING_ANY, !!(val & TSFLAGS_ANY));
940
941 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
942 sock_enable_timestamp(sk,
943 SOCK_TIMESTAMPING_RX_SOFTWARE);
944 else
945 sock_disable_timestamp(sk,
946 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
947 return 0;
948 }
949
950 #if defined(CONFIG_CGROUP_BPF)
bpf_skops_tx_timestamping(struct sock * sk,struct sk_buff * skb,int op)951 void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op)
952 {
953 struct bpf_sock_ops_kern sock_ops;
954
955 memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp));
956 sock_ops.op = op;
957 sock_ops.is_fullsock = 1;
958 sock_ops.sk = sk;
959 bpf_skops_init_skb(&sock_ops, skb, 0);
960 __cgroup_bpf_run_filter_sock_ops(sk, &sock_ops, CGROUP_SOCK_OPS);
961 }
962 #endif
963
sock_set_keepalive(struct sock * sk)964 void sock_set_keepalive(struct sock *sk)
965 {
966 lock_sock(sk);
967 if (sk->sk_prot->keepalive)
968 sk->sk_prot->keepalive(sk, true);
969 sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
970 release_sock(sk);
971 }
972 EXPORT_SYMBOL(sock_set_keepalive);
973
__sock_set_rcvbuf(struct sock * sk,int val)974 static void __sock_set_rcvbuf(struct sock *sk, int val)
975 {
976 /* Ensure val * 2 fits into an int, to prevent max_t() from treating it
977 * as a negative value.
978 */
979 val = min_t(int, val, INT_MAX / 2);
980 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
981
982 /* We double it on the way in to account for "struct sk_buff" etc.
983 * overhead. Applications assume that the SO_RCVBUF setting they make
984 * will allow that much actual data to be received on that socket.
985 *
986 * Applications are unaware that "struct sk_buff" and other overheads
987 * allocate from the receive buffer during socket buffer allocation.
988 *
989 * And after considering the possible alternatives, returning the value
990 * we actually used in getsockopt is the most desirable behavior.
991 */
992 WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
993 }
994
sock_set_rcvbuf(struct sock * sk,int val)995 void sock_set_rcvbuf(struct sock *sk, int val)
996 {
997 lock_sock(sk);
998 __sock_set_rcvbuf(sk, val);
999 release_sock(sk);
1000 }
1001 EXPORT_SYMBOL(sock_set_rcvbuf);
1002
__sock_set_mark(struct sock * sk,u32 val)1003 static void __sock_set_mark(struct sock *sk, u32 val)
1004 {
1005 if (val != sk->sk_mark) {
1006 WRITE_ONCE(sk->sk_mark, val);
1007 sk_dst_reset(sk);
1008 }
1009 }
1010
sock_set_mark(struct sock * sk,u32 val)1011 void sock_set_mark(struct sock *sk, u32 val)
1012 {
1013 lock_sock(sk);
1014 __sock_set_mark(sk, val);
1015 release_sock(sk);
1016 }
1017 EXPORT_SYMBOL(sock_set_mark);
1018
sock_release_reserved_memory(struct sock * sk,int bytes)1019 static void sock_release_reserved_memory(struct sock *sk, int bytes)
1020 {
1021 /* Round down bytes to multiple of pages */
1022 bytes = round_down(bytes, PAGE_SIZE);
1023
1024 WARN_ON(bytes > sk->sk_reserved_mem);
1025 WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes);
1026 sk_mem_reclaim(sk);
1027 }
1028
sock_reserve_memory(struct sock * sk,int bytes)1029 static int sock_reserve_memory(struct sock *sk, int bytes)
1030 {
1031 long allocated;
1032 bool charged;
1033 int pages;
1034
1035 if (!mem_cgroup_sk_enabled(sk) || !sk_has_account(sk))
1036 return -EOPNOTSUPP;
1037
1038 if (!bytes)
1039 return 0;
1040
1041 pages = sk_mem_pages(bytes);
1042
1043 /* pre-charge to memcg */
1044 charged = mem_cgroup_sk_charge(sk, pages,
1045 GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1046 if (!charged)
1047 return -ENOMEM;
1048
1049 /* pre-charge to forward_alloc */
1050 sk_memory_allocated_add(sk, pages);
1051 allocated = sk_memory_allocated(sk);
1052 /* If the system goes into memory pressure with this
1053 * precharge, give up and return error.
1054 */
1055 if (allocated > sk_prot_mem_limits(sk, 1)) {
1056 sk_memory_allocated_sub(sk, pages);
1057 mem_cgroup_sk_uncharge(sk, pages);
1058 return -ENOMEM;
1059 }
1060 sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1061
1062 WRITE_ONCE(sk->sk_reserved_mem,
1063 sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1064
1065 return 0;
1066 }
1067
1068 #ifdef CONFIG_PAGE_POOL
1069
1070 /* This is the number of tokens and frags that the user can SO_DEVMEM_DONTNEED
1071 * in 1 syscall. The limit exists to limit the amount of memory the kernel
1072 * allocates to copy these tokens, and to prevent looping over the frags for
1073 * too long.
1074 */
1075 #define MAX_DONTNEED_TOKENS 128
1076 #define MAX_DONTNEED_FRAGS 1024
1077
1078 static noinline_for_stack int
sock_devmem_dontneed(struct sock * sk,sockptr_t optval,unsigned int optlen)1079 sock_devmem_dontneed(struct sock *sk, sockptr_t optval, unsigned int optlen)
1080 {
1081 unsigned int num_tokens, i, j, k, netmem_num = 0;
1082 struct dmabuf_token *tokens;
1083 int ret = 0, num_frags = 0;
1084 netmem_ref netmems[16];
1085
1086 if (!sk_is_tcp(sk))
1087 return -EBADF;
1088
1089 if (optlen % sizeof(*tokens) ||
1090 optlen > sizeof(*tokens) * MAX_DONTNEED_TOKENS)
1091 return -EINVAL;
1092
1093 num_tokens = optlen / sizeof(*tokens);
1094 tokens = kvmalloc_array(num_tokens, sizeof(*tokens), GFP_KERNEL);
1095 if (!tokens)
1096 return -ENOMEM;
1097
1098 if (copy_from_sockptr(tokens, optval, optlen)) {
1099 kvfree(tokens);
1100 return -EFAULT;
1101 }
1102
1103 xa_lock_bh(&sk->sk_user_frags);
1104 for (i = 0; i < num_tokens; i++) {
1105 for (j = 0; j < tokens[i].token_count; j++) {
1106 if (++num_frags > MAX_DONTNEED_FRAGS)
1107 goto frag_limit_reached;
1108
1109 netmem_ref netmem = (__force netmem_ref)__xa_erase(
1110 &sk->sk_user_frags, tokens[i].token_start + j);
1111
1112 if (!netmem || WARN_ON_ONCE(!netmem_is_net_iov(netmem)))
1113 continue;
1114
1115 netmems[netmem_num++] = netmem;
1116 if (netmem_num == ARRAY_SIZE(netmems)) {
1117 xa_unlock_bh(&sk->sk_user_frags);
1118 for (k = 0; k < netmem_num; k++)
1119 WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1120 netmem_num = 0;
1121 xa_lock_bh(&sk->sk_user_frags);
1122 }
1123 ret++;
1124 }
1125 }
1126
1127 frag_limit_reached:
1128 xa_unlock_bh(&sk->sk_user_frags);
1129 for (k = 0; k < netmem_num; k++)
1130 WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1131
1132 kvfree(tokens);
1133 return ret;
1134 }
1135 #endif
1136
sockopt_lock_sock(struct sock * sk)1137 void sockopt_lock_sock(struct sock *sk)
1138 {
1139 /* When current->bpf_ctx is set, the setsockopt is called from
1140 * a bpf prog. bpf has ensured the sk lock has been
1141 * acquired before calling setsockopt().
1142 */
1143 if (has_current_bpf_ctx())
1144 return;
1145
1146 lock_sock(sk);
1147 }
1148 EXPORT_SYMBOL(sockopt_lock_sock);
1149
sockopt_release_sock(struct sock * sk)1150 void sockopt_release_sock(struct sock *sk)
1151 {
1152 if (has_current_bpf_ctx())
1153 return;
1154
1155 release_sock(sk);
1156 }
1157 EXPORT_SYMBOL(sockopt_release_sock);
1158
sockopt_ns_capable(struct user_namespace * ns,int cap)1159 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1160 {
1161 return has_current_bpf_ctx() || ns_capable(ns, cap);
1162 }
1163 EXPORT_SYMBOL(sockopt_ns_capable);
1164
sockopt_capable(int cap)1165 bool sockopt_capable(int cap)
1166 {
1167 return has_current_bpf_ctx() || capable(cap);
1168 }
1169 EXPORT_SYMBOL(sockopt_capable);
1170
sockopt_validate_clockid(__kernel_clockid_t value)1171 static int sockopt_validate_clockid(__kernel_clockid_t value)
1172 {
1173 switch (value) {
1174 case CLOCK_REALTIME:
1175 case CLOCK_MONOTONIC:
1176 case CLOCK_TAI:
1177 return 0;
1178 }
1179 return -EINVAL;
1180 }
1181
1182 /*
1183 * This is meant for all protocols to use and covers goings on
1184 * at the socket level. Everything here is generic.
1185 */
1186
sk_setsockopt(struct sock * sk,int level,int optname,sockptr_t optval,unsigned int optlen)1187 int sk_setsockopt(struct sock *sk, int level, int optname,
1188 sockptr_t optval, unsigned int optlen)
1189 {
1190 struct so_timestamping timestamping;
1191 struct socket *sock = sk->sk_socket;
1192 struct sock_txtime sk_txtime;
1193 int val;
1194 int valbool;
1195 struct linger ling;
1196 int ret = 0;
1197
1198 /*
1199 * Options without arguments
1200 */
1201
1202 if (optname == SO_BINDTODEVICE)
1203 return sock_setbindtodevice(sk, optval, optlen);
1204
1205 if (optlen < sizeof(int))
1206 return -EINVAL;
1207
1208 if (copy_from_sockptr(&val, optval, sizeof(val)))
1209 return -EFAULT;
1210
1211 valbool = val ? 1 : 0;
1212
1213 /* handle options which do not require locking the socket. */
1214 switch (optname) {
1215 case SO_PRIORITY:
1216 if (sk_set_prio_allowed(sk, val)) {
1217 sock_set_priority(sk, val);
1218 return 0;
1219 }
1220 return -EPERM;
1221 case SO_TYPE:
1222 case SO_PROTOCOL:
1223 case SO_DOMAIN:
1224 case SO_ERROR:
1225 return -ENOPROTOOPT;
1226 #ifdef CONFIG_NET_RX_BUSY_POLL
1227 case SO_BUSY_POLL:
1228 if (val < 0)
1229 return -EINVAL;
1230 WRITE_ONCE(sk->sk_ll_usec, val);
1231 return 0;
1232 case SO_PREFER_BUSY_POLL:
1233 if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1234 return -EPERM;
1235 WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1236 return 0;
1237 case SO_BUSY_POLL_BUDGET:
1238 if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1239 !sockopt_capable(CAP_NET_ADMIN))
1240 return -EPERM;
1241 if (val < 0 || val > U16_MAX)
1242 return -EINVAL;
1243 WRITE_ONCE(sk->sk_busy_poll_budget, val);
1244 return 0;
1245 #endif
1246 case SO_MAX_PACING_RATE:
1247 {
1248 unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1249 unsigned long pacing_rate;
1250
1251 if (sizeof(ulval) != sizeof(val) &&
1252 optlen >= sizeof(ulval) &&
1253 copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1254 return -EFAULT;
1255 }
1256 if (ulval != ~0UL)
1257 cmpxchg(&sk->sk_pacing_status,
1258 SK_PACING_NONE,
1259 SK_PACING_NEEDED);
1260 /* Pairs with READ_ONCE() from sk_getsockopt() */
1261 WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1262 pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1263 if (ulval < pacing_rate)
1264 WRITE_ONCE(sk->sk_pacing_rate, ulval);
1265 return 0;
1266 }
1267 case SO_TXREHASH:
1268 if (!sk_is_tcp(sk))
1269 return -EOPNOTSUPP;
1270 if (val < -1 || val > 1)
1271 return -EINVAL;
1272 if ((u8)val == SOCK_TXREHASH_DEFAULT)
1273 val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1274 /* Paired with READ_ONCE() in tcp_rtx_synack()
1275 * and sk_getsockopt().
1276 */
1277 WRITE_ONCE(sk->sk_txrehash, (u8)val);
1278 return 0;
1279 case SO_PEEK_OFF:
1280 {
1281 int (*set_peek_off)(struct sock *sk, int val);
1282
1283 set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1284 if (set_peek_off)
1285 ret = set_peek_off(sk, val);
1286 else
1287 ret = -EOPNOTSUPP;
1288 return ret;
1289 }
1290 #ifdef CONFIG_PAGE_POOL
1291 case SO_DEVMEM_DONTNEED:
1292 return sock_devmem_dontneed(sk, optval, optlen);
1293 #endif
1294 case SO_SNDTIMEO_OLD:
1295 case SO_SNDTIMEO_NEW:
1296 return sock_set_timeout(&sk->sk_sndtimeo, optval,
1297 optlen, optname == SO_SNDTIMEO_OLD);
1298 case SO_RCVTIMEO_OLD:
1299 case SO_RCVTIMEO_NEW:
1300 return sock_set_timeout(&sk->sk_rcvtimeo, optval,
1301 optlen, optname == SO_RCVTIMEO_OLD);
1302 }
1303
1304 sockopt_lock_sock(sk);
1305
1306 switch (optname) {
1307 case SO_DEBUG:
1308 if (val && !sockopt_capable(CAP_NET_ADMIN))
1309 ret = -EACCES;
1310 else
1311 sock_valbool_flag(sk, SOCK_DBG, valbool);
1312 break;
1313 case SO_REUSEADDR:
1314 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1315 break;
1316 case SO_REUSEPORT:
1317 if (valbool && !sk_is_inet(sk))
1318 ret = -EOPNOTSUPP;
1319 else
1320 sk->sk_reuseport = valbool;
1321 break;
1322 case SO_DONTROUTE:
1323 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1324 sk_dst_reset(sk);
1325 break;
1326 case SO_BROADCAST:
1327 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1328 break;
1329 case SO_SNDBUF:
1330 /* Don't error on this BSD doesn't and if you think
1331 * about it this is right. Otherwise apps have to
1332 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1333 * are treated in BSD as hints
1334 */
1335 val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1336 set_sndbuf:
1337 /* Ensure val * 2 fits into an int, to prevent max_t()
1338 * from treating it as a negative value.
1339 */
1340 val = min_t(int, val, INT_MAX / 2);
1341 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1342 WRITE_ONCE(sk->sk_sndbuf,
1343 max_t(int, val * 2, SOCK_MIN_SNDBUF));
1344 /* Wake up sending tasks if we upped the value. */
1345 sk->sk_write_space(sk);
1346 break;
1347
1348 case SO_SNDBUFFORCE:
1349 if (!sockopt_capable(CAP_NET_ADMIN)) {
1350 ret = -EPERM;
1351 break;
1352 }
1353
1354 /* No negative values (to prevent underflow, as val will be
1355 * multiplied by 2).
1356 */
1357 if (val < 0)
1358 val = 0;
1359 goto set_sndbuf;
1360
1361 case SO_RCVBUF:
1362 /* Don't error on this BSD doesn't and if you think
1363 * about it this is right. Otherwise apps have to
1364 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1365 * are treated in BSD as hints
1366 */
1367 __sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1368 break;
1369
1370 case SO_RCVBUFFORCE:
1371 if (!sockopt_capable(CAP_NET_ADMIN)) {
1372 ret = -EPERM;
1373 break;
1374 }
1375
1376 /* No negative values (to prevent underflow, as val will be
1377 * multiplied by 2).
1378 */
1379 __sock_set_rcvbuf(sk, max(val, 0));
1380 break;
1381
1382 case SO_KEEPALIVE:
1383 if (sk->sk_prot->keepalive)
1384 sk->sk_prot->keepalive(sk, valbool);
1385 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1386 break;
1387
1388 case SO_OOBINLINE:
1389 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1390 break;
1391
1392 case SO_NO_CHECK:
1393 sk->sk_no_check_tx = valbool;
1394 break;
1395
1396 case SO_LINGER:
1397 if (optlen < sizeof(ling)) {
1398 ret = -EINVAL; /* 1003.1g */
1399 break;
1400 }
1401 if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1402 ret = -EFAULT;
1403 break;
1404 }
1405 if (!ling.l_onoff) {
1406 sock_reset_flag(sk, SOCK_LINGER);
1407 } else {
1408 unsigned long t_sec = ling.l_linger;
1409
1410 if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1411 WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1412 else
1413 WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
1414 sock_set_flag(sk, SOCK_LINGER);
1415 }
1416 break;
1417
1418 case SO_BSDCOMPAT:
1419 break;
1420
1421 case SO_TIMESTAMP_OLD:
1422 case SO_TIMESTAMP_NEW:
1423 case SO_TIMESTAMPNS_OLD:
1424 case SO_TIMESTAMPNS_NEW:
1425 sock_set_timestamp(sk, optname, valbool);
1426 break;
1427
1428 case SO_TIMESTAMPING_NEW:
1429 case SO_TIMESTAMPING_OLD:
1430 if (optlen == sizeof(timestamping)) {
1431 if (copy_from_sockptr(×tamping, optval,
1432 sizeof(timestamping))) {
1433 ret = -EFAULT;
1434 break;
1435 }
1436 } else {
1437 memset(×tamping, 0, sizeof(timestamping));
1438 timestamping.flags = val;
1439 }
1440 ret = sock_set_timestamping(sk, optname, timestamping);
1441 break;
1442
1443 case SO_RCVLOWAT:
1444 {
1445 int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
1446
1447 if (val < 0)
1448 val = INT_MAX;
1449 if (sock)
1450 set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1451 if (set_rcvlowat)
1452 ret = set_rcvlowat(sk, val);
1453 else
1454 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1455 break;
1456 }
1457 case SO_ATTACH_FILTER: {
1458 struct sock_fprog fprog;
1459
1460 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1461 if (!ret)
1462 ret = sk_attach_filter(&fprog, sk);
1463 break;
1464 }
1465 case SO_ATTACH_BPF:
1466 ret = -EINVAL;
1467 if (optlen == sizeof(u32)) {
1468 u32 ufd;
1469
1470 ret = -EFAULT;
1471 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1472 break;
1473
1474 ret = sk_attach_bpf(ufd, sk);
1475 }
1476 break;
1477
1478 case SO_ATTACH_REUSEPORT_CBPF: {
1479 struct sock_fprog fprog;
1480
1481 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1482 if (!ret)
1483 ret = sk_reuseport_attach_filter(&fprog, sk);
1484 break;
1485 }
1486 case SO_ATTACH_REUSEPORT_EBPF:
1487 ret = -EINVAL;
1488 if (optlen == sizeof(u32)) {
1489 u32 ufd;
1490
1491 ret = -EFAULT;
1492 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1493 break;
1494
1495 ret = sk_reuseport_attach_bpf(ufd, sk);
1496 }
1497 break;
1498
1499 case SO_DETACH_REUSEPORT_BPF:
1500 ret = reuseport_detach_prog(sk);
1501 break;
1502
1503 case SO_DETACH_FILTER:
1504 ret = sk_detach_filter(sk);
1505 break;
1506
1507 case SO_LOCK_FILTER:
1508 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1509 ret = -EPERM;
1510 else
1511 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1512 break;
1513
1514 case SO_MARK:
1515 if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1516 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1517 ret = -EPERM;
1518 break;
1519 }
1520
1521 __sock_set_mark(sk, val);
1522 break;
1523 case SO_RCVMARK:
1524 sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1525 break;
1526
1527 case SO_RCVPRIORITY:
1528 sock_valbool_flag(sk, SOCK_RCVPRIORITY, valbool);
1529 break;
1530
1531 case SO_RXQ_OVFL:
1532 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1533 break;
1534
1535 case SO_WIFI_STATUS:
1536 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1537 break;
1538
1539 case SO_NOFCS:
1540 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1541 break;
1542
1543 case SO_SELECT_ERR_QUEUE:
1544 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1545 break;
1546
1547 case SO_PASSCRED:
1548 if (sk_may_scm_recv(sk))
1549 sk->sk_scm_credentials = valbool;
1550 else
1551 ret = -EOPNOTSUPP;
1552 break;
1553
1554 case SO_PASSSEC:
1555 if (IS_ENABLED(CONFIG_SECURITY_NETWORK) && sk_may_scm_recv(sk))
1556 sk->sk_scm_security = valbool;
1557 else
1558 ret = -EOPNOTSUPP;
1559 break;
1560
1561 case SO_PASSPIDFD:
1562 if (sk_is_unix(sk))
1563 sk->sk_scm_pidfd = valbool;
1564 else
1565 ret = -EOPNOTSUPP;
1566 break;
1567
1568 case SO_PASSRIGHTS:
1569 if (sk_is_unix(sk))
1570 sk->sk_scm_rights = valbool;
1571 else
1572 ret = -EOPNOTSUPP;
1573 break;
1574
1575 case SO_INCOMING_CPU:
1576 reuseport_update_incoming_cpu(sk, val);
1577 break;
1578
1579 case SO_CNX_ADVICE:
1580 if (val == 1)
1581 dst_negative_advice(sk);
1582 break;
1583
1584 case SO_ZEROCOPY:
1585 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1586 if (!(sk_is_tcp(sk) ||
1587 (sk->sk_type == SOCK_DGRAM &&
1588 sk->sk_protocol == IPPROTO_UDP)))
1589 ret = -EOPNOTSUPP;
1590 } else if (sk->sk_family != PF_RDS) {
1591 ret = -EOPNOTSUPP;
1592 }
1593 if (!ret) {
1594 if (val < 0 || val > 1)
1595 ret = -EINVAL;
1596 else
1597 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1598 }
1599 break;
1600
1601 case SO_TXTIME:
1602 if (optlen != sizeof(struct sock_txtime)) {
1603 ret = -EINVAL;
1604 break;
1605 } else if (copy_from_sockptr(&sk_txtime, optval,
1606 sizeof(struct sock_txtime))) {
1607 ret = -EFAULT;
1608 break;
1609 } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1610 ret = -EINVAL;
1611 break;
1612 }
1613 /* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1614 * scheduler has enough safe guards.
1615 */
1616 if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1617 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1618 ret = -EPERM;
1619 break;
1620 }
1621
1622 ret = sockopt_validate_clockid(sk_txtime.clockid);
1623 if (ret)
1624 break;
1625
1626 sock_valbool_flag(sk, SOCK_TXTIME, true);
1627 sk->sk_clockid = sk_txtime.clockid;
1628 sk->sk_txtime_deadline_mode =
1629 !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1630 sk->sk_txtime_report_errors =
1631 !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1632 break;
1633
1634 case SO_BINDTOIFINDEX:
1635 ret = sock_bindtoindex_locked(sk, val);
1636 break;
1637
1638 case SO_BUF_LOCK:
1639 if (val & ~SOCK_BUF_LOCK_MASK) {
1640 ret = -EINVAL;
1641 break;
1642 }
1643 sk->sk_userlocks = val | (sk->sk_userlocks &
1644 ~SOCK_BUF_LOCK_MASK);
1645 break;
1646
1647 case SO_RESERVE_MEM:
1648 {
1649 int delta;
1650
1651 if (val < 0) {
1652 ret = -EINVAL;
1653 break;
1654 }
1655
1656 delta = val - sk->sk_reserved_mem;
1657 if (delta < 0)
1658 sock_release_reserved_memory(sk, -delta);
1659 else
1660 ret = sock_reserve_memory(sk, delta);
1661 break;
1662 }
1663
1664 default:
1665 ret = -ENOPROTOOPT;
1666 break;
1667 }
1668 sockopt_release_sock(sk);
1669 return ret;
1670 }
1671
sock_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)1672 int sock_setsockopt(struct socket *sock, int level, int optname,
1673 sockptr_t optval, unsigned int optlen)
1674 {
1675 return sk_setsockopt(sock->sk, level, optname,
1676 optval, optlen);
1677 }
1678 EXPORT_SYMBOL(sock_setsockopt);
1679
sk_get_peer_cred(struct sock * sk)1680 static const struct cred *sk_get_peer_cred(struct sock *sk)
1681 {
1682 const struct cred *cred;
1683
1684 spin_lock(&sk->sk_peer_lock);
1685 cred = get_cred(sk->sk_peer_cred);
1686 spin_unlock(&sk->sk_peer_lock);
1687
1688 return cred;
1689 }
1690
cred_to_ucred(struct pid * pid,const struct cred * cred,struct ucred * ucred)1691 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1692 struct ucred *ucred)
1693 {
1694 ucred->pid = pid_vnr(pid);
1695 ucred->uid = ucred->gid = -1;
1696 if (cred) {
1697 struct user_namespace *current_ns = current_user_ns();
1698
1699 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1700 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1701 }
1702 }
1703
groups_to_user(sockptr_t dst,const struct group_info * src)1704 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1705 {
1706 struct user_namespace *user_ns = current_user_ns();
1707 int i;
1708
1709 for (i = 0; i < src->ngroups; i++) {
1710 gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1711
1712 if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1713 return -EFAULT;
1714 }
1715
1716 return 0;
1717 }
1718
sk_getsockopt(struct sock * sk,int level,int optname,sockptr_t optval,sockptr_t optlen)1719 int sk_getsockopt(struct sock *sk, int level, int optname,
1720 sockptr_t optval, sockptr_t optlen)
1721 {
1722 struct socket *sock = sk->sk_socket;
1723
1724 union {
1725 int val;
1726 u64 val64;
1727 unsigned long ulval;
1728 struct linger ling;
1729 struct old_timeval32 tm32;
1730 struct __kernel_old_timeval tm;
1731 struct __kernel_sock_timeval stm;
1732 struct sock_txtime txtime;
1733 struct so_timestamping timestamping;
1734 } v;
1735
1736 int lv = sizeof(int);
1737 int len;
1738
1739 if (copy_from_sockptr(&len, optlen, sizeof(int)))
1740 return -EFAULT;
1741 if (len < 0)
1742 return -EINVAL;
1743
1744 memset(&v, 0, sizeof(v));
1745
1746 switch (optname) {
1747 case SO_DEBUG:
1748 v.val = sock_flag(sk, SOCK_DBG);
1749 break;
1750
1751 case SO_DONTROUTE:
1752 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1753 break;
1754
1755 case SO_BROADCAST:
1756 v.val = sock_flag(sk, SOCK_BROADCAST);
1757 break;
1758
1759 case SO_SNDBUF:
1760 v.val = READ_ONCE(sk->sk_sndbuf);
1761 break;
1762
1763 case SO_RCVBUF:
1764 v.val = READ_ONCE(sk->sk_rcvbuf);
1765 break;
1766
1767 case SO_REUSEADDR:
1768 v.val = sk->sk_reuse;
1769 break;
1770
1771 case SO_REUSEPORT:
1772 v.val = sk->sk_reuseport;
1773 break;
1774
1775 case SO_KEEPALIVE:
1776 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1777 break;
1778
1779 case SO_TYPE:
1780 v.val = sk->sk_type;
1781 break;
1782
1783 case SO_PROTOCOL:
1784 v.val = sk->sk_protocol;
1785 break;
1786
1787 case SO_DOMAIN:
1788 v.val = sk->sk_family;
1789 break;
1790
1791 case SO_ERROR:
1792 v.val = -sock_error(sk);
1793 if (v.val == 0)
1794 v.val = xchg(&sk->sk_err_soft, 0);
1795 break;
1796
1797 case SO_OOBINLINE:
1798 v.val = sock_flag(sk, SOCK_URGINLINE);
1799 break;
1800
1801 case SO_NO_CHECK:
1802 v.val = sk->sk_no_check_tx;
1803 break;
1804
1805 case SO_PRIORITY:
1806 v.val = READ_ONCE(sk->sk_priority);
1807 break;
1808
1809 case SO_LINGER:
1810 lv = sizeof(v.ling);
1811 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1812 v.ling.l_linger = READ_ONCE(sk->sk_lingertime) / HZ;
1813 break;
1814
1815 case SO_BSDCOMPAT:
1816 break;
1817
1818 case SO_TIMESTAMP_OLD:
1819 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1820 !sock_flag(sk, SOCK_TSTAMP_NEW) &&
1821 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1822 break;
1823
1824 case SO_TIMESTAMPNS_OLD:
1825 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1826 break;
1827
1828 case SO_TIMESTAMP_NEW:
1829 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1830 break;
1831
1832 case SO_TIMESTAMPNS_NEW:
1833 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1834 break;
1835
1836 case SO_TIMESTAMPING_OLD:
1837 case SO_TIMESTAMPING_NEW:
1838 lv = sizeof(v.timestamping);
1839 /* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1840 * returning the flags when they were set through the same option.
1841 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1842 */
1843 if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1844 v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1845 v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1846 }
1847 break;
1848
1849 case SO_RCVTIMEO_OLD:
1850 case SO_RCVTIMEO_NEW:
1851 lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1852 SO_RCVTIMEO_OLD == optname);
1853 break;
1854
1855 case SO_SNDTIMEO_OLD:
1856 case SO_SNDTIMEO_NEW:
1857 lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1858 SO_SNDTIMEO_OLD == optname);
1859 break;
1860
1861 case SO_RCVLOWAT:
1862 v.val = READ_ONCE(sk->sk_rcvlowat);
1863 break;
1864
1865 case SO_SNDLOWAT:
1866 v.val = 1;
1867 break;
1868
1869 case SO_PASSCRED:
1870 if (!sk_may_scm_recv(sk))
1871 return -EOPNOTSUPP;
1872
1873 v.val = sk->sk_scm_credentials;
1874 break;
1875
1876 case SO_PASSPIDFD:
1877 if (!sk_is_unix(sk))
1878 return -EOPNOTSUPP;
1879
1880 v.val = sk->sk_scm_pidfd;
1881 break;
1882
1883 case SO_PASSRIGHTS:
1884 if (!sk_is_unix(sk))
1885 return -EOPNOTSUPP;
1886
1887 v.val = sk->sk_scm_rights;
1888 break;
1889
1890 case SO_PEERCRED:
1891 {
1892 struct ucred peercred;
1893 if (len > sizeof(peercred))
1894 len = sizeof(peercred);
1895
1896 spin_lock(&sk->sk_peer_lock);
1897 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1898 spin_unlock(&sk->sk_peer_lock);
1899
1900 if (copy_to_sockptr(optval, &peercred, len))
1901 return -EFAULT;
1902 goto lenout;
1903 }
1904
1905 case SO_PEERPIDFD:
1906 {
1907 struct pid *peer_pid;
1908 struct file *pidfd_file = NULL;
1909 unsigned int flags = 0;
1910 int pidfd;
1911
1912 if (len > sizeof(pidfd))
1913 len = sizeof(pidfd);
1914
1915 spin_lock(&sk->sk_peer_lock);
1916 peer_pid = get_pid(sk->sk_peer_pid);
1917 spin_unlock(&sk->sk_peer_lock);
1918
1919 if (!peer_pid)
1920 return -ENODATA;
1921
1922 /* The use of PIDFD_STALE requires stashing of struct pid
1923 * on pidfs with pidfs_register_pid() and only AF_UNIX
1924 * were prepared for this.
1925 */
1926 if (sk->sk_family == AF_UNIX)
1927 flags = PIDFD_STALE;
1928
1929 pidfd = pidfd_prepare(peer_pid, flags, &pidfd_file);
1930 put_pid(peer_pid);
1931 if (pidfd < 0)
1932 return pidfd;
1933
1934 if (copy_to_sockptr(optval, &pidfd, len) ||
1935 copy_to_sockptr(optlen, &len, sizeof(int))) {
1936 put_unused_fd(pidfd);
1937 fput(pidfd_file);
1938
1939 return -EFAULT;
1940 }
1941
1942 fd_install(pidfd, pidfd_file);
1943 return 0;
1944 }
1945
1946 case SO_PEERGROUPS:
1947 {
1948 const struct cred *cred;
1949 int ret, n;
1950
1951 cred = sk_get_peer_cred(sk);
1952 if (!cred)
1953 return -ENODATA;
1954
1955 n = cred->group_info->ngroups;
1956 if (len < n * sizeof(gid_t)) {
1957 len = n * sizeof(gid_t);
1958 put_cred(cred);
1959 return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1960 }
1961 len = n * sizeof(gid_t);
1962
1963 ret = groups_to_user(optval, cred->group_info);
1964 put_cred(cred);
1965 if (ret)
1966 return ret;
1967 goto lenout;
1968 }
1969
1970 case SO_PEERNAME:
1971 {
1972 struct sockaddr_storage address;
1973
1974 lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1975 if (lv < 0)
1976 return -ENOTCONN;
1977 if (lv < len)
1978 return -EINVAL;
1979 if (copy_to_sockptr(optval, &address, len))
1980 return -EFAULT;
1981 goto lenout;
1982 }
1983
1984 /* Dubious BSD thing... Probably nobody even uses it, but
1985 * the UNIX standard wants it for whatever reason... -DaveM
1986 */
1987 case SO_ACCEPTCONN:
1988 v.val = sk->sk_state == TCP_LISTEN;
1989 break;
1990
1991 case SO_PASSSEC:
1992 if (!IS_ENABLED(CONFIG_SECURITY_NETWORK) || !sk_may_scm_recv(sk))
1993 return -EOPNOTSUPP;
1994
1995 v.val = sk->sk_scm_security;
1996 break;
1997
1998 case SO_PEERSEC:
1999 return security_socket_getpeersec_stream(sock,
2000 optval, optlen, len);
2001
2002 case SO_MARK:
2003 v.val = READ_ONCE(sk->sk_mark);
2004 break;
2005
2006 case SO_RCVMARK:
2007 v.val = sock_flag(sk, SOCK_RCVMARK);
2008 break;
2009
2010 case SO_RCVPRIORITY:
2011 v.val = sock_flag(sk, SOCK_RCVPRIORITY);
2012 break;
2013
2014 case SO_RXQ_OVFL:
2015 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
2016 break;
2017
2018 case SO_WIFI_STATUS:
2019 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
2020 break;
2021
2022 case SO_PEEK_OFF:
2023 if (!READ_ONCE(sock->ops)->set_peek_off)
2024 return -EOPNOTSUPP;
2025
2026 v.val = READ_ONCE(sk->sk_peek_off);
2027 break;
2028 case SO_NOFCS:
2029 v.val = sock_flag(sk, SOCK_NOFCS);
2030 break;
2031
2032 case SO_BINDTODEVICE:
2033 return sock_getbindtodevice(sk, optval, optlen, len);
2034
2035 case SO_GET_FILTER:
2036 len = sk_get_filter(sk, optval, len);
2037 if (len < 0)
2038 return len;
2039
2040 goto lenout;
2041
2042 case SO_LOCK_FILTER:
2043 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
2044 break;
2045
2046 case SO_BPF_EXTENSIONS:
2047 v.val = bpf_tell_extensions();
2048 break;
2049
2050 case SO_SELECT_ERR_QUEUE:
2051 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
2052 break;
2053
2054 #ifdef CONFIG_NET_RX_BUSY_POLL
2055 case SO_BUSY_POLL:
2056 v.val = READ_ONCE(sk->sk_ll_usec);
2057 break;
2058 case SO_PREFER_BUSY_POLL:
2059 v.val = READ_ONCE(sk->sk_prefer_busy_poll);
2060 break;
2061 #endif
2062
2063 case SO_MAX_PACING_RATE:
2064 /* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
2065 if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
2066 lv = sizeof(v.ulval);
2067 v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
2068 } else {
2069 /* 32bit version */
2070 v.val = min_t(unsigned long, ~0U,
2071 READ_ONCE(sk->sk_max_pacing_rate));
2072 }
2073 break;
2074
2075 case SO_INCOMING_CPU:
2076 v.val = READ_ONCE(sk->sk_incoming_cpu);
2077 break;
2078
2079 case SO_MEMINFO:
2080 {
2081 u32 meminfo[SK_MEMINFO_VARS];
2082
2083 sk_get_meminfo(sk, meminfo);
2084
2085 len = min_t(unsigned int, len, sizeof(meminfo));
2086 if (copy_to_sockptr(optval, &meminfo, len))
2087 return -EFAULT;
2088
2089 goto lenout;
2090 }
2091
2092 #ifdef CONFIG_NET_RX_BUSY_POLL
2093 case SO_INCOMING_NAPI_ID:
2094 v.val = READ_ONCE(sk->sk_napi_id);
2095
2096 /* aggregate non-NAPI IDs down to 0 */
2097 if (!napi_id_valid(v.val))
2098 v.val = 0;
2099
2100 break;
2101 #endif
2102
2103 case SO_COOKIE:
2104 lv = sizeof(u64);
2105 if (len < lv)
2106 return -EINVAL;
2107 v.val64 = sock_gen_cookie(sk);
2108 break;
2109
2110 case SO_ZEROCOPY:
2111 v.val = sock_flag(sk, SOCK_ZEROCOPY);
2112 break;
2113
2114 case SO_TXTIME:
2115 lv = sizeof(v.txtime);
2116 v.txtime.clockid = sk->sk_clockid;
2117 v.txtime.flags |= sk->sk_txtime_deadline_mode ?
2118 SOF_TXTIME_DEADLINE_MODE : 0;
2119 v.txtime.flags |= sk->sk_txtime_report_errors ?
2120 SOF_TXTIME_REPORT_ERRORS : 0;
2121 break;
2122
2123 case SO_BINDTOIFINDEX:
2124 v.val = READ_ONCE(sk->sk_bound_dev_if);
2125 break;
2126
2127 case SO_NETNS_COOKIE:
2128 lv = sizeof(u64);
2129 if (len != lv)
2130 return -EINVAL;
2131 v.val64 = sock_net(sk)->net_cookie;
2132 break;
2133
2134 case SO_BUF_LOCK:
2135 v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
2136 break;
2137
2138 case SO_RESERVE_MEM:
2139 v.val = READ_ONCE(sk->sk_reserved_mem);
2140 break;
2141
2142 case SO_TXREHASH:
2143 if (!sk_is_tcp(sk))
2144 return -EOPNOTSUPP;
2145
2146 /* Paired with WRITE_ONCE() in sk_setsockopt() */
2147 v.val = READ_ONCE(sk->sk_txrehash);
2148 break;
2149
2150 default:
2151 /* We implement the SO_SNDLOWAT etc to not be settable
2152 * (1003.1g 7).
2153 */
2154 return -ENOPROTOOPT;
2155 }
2156
2157 if (len > lv)
2158 len = lv;
2159 if (copy_to_sockptr(optval, &v, len))
2160 return -EFAULT;
2161 lenout:
2162 if (copy_to_sockptr(optlen, &len, sizeof(int)))
2163 return -EFAULT;
2164 return 0;
2165 }
2166
2167 /*
2168 * Initialize an sk_lock.
2169 *
2170 * (We also register the sk_lock with the lock validator.)
2171 */
sock_lock_init(struct sock * sk)2172 static inline void sock_lock_init(struct sock *sk)
2173 {
2174 sk_owner_clear(sk);
2175
2176 if (sk->sk_kern_sock)
2177 sock_lock_init_class_and_name(
2178 sk,
2179 af_family_kern_slock_key_strings[sk->sk_family],
2180 af_family_kern_slock_keys + sk->sk_family,
2181 af_family_kern_key_strings[sk->sk_family],
2182 af_family_kern_keys + sk->sk_family);
2183 else
2184 sock_lock_init_class_and_name(
2185 sk,
2186 af_family_slock_key_strings[sk->sk_family],
2187 af_family_slock_keys + sk->sk_family,
2188 af_family_key_strings[sk->sk_family],
2189 af_family_keys + sk->sk_family);
2190 }
2191
2192 /*
2193 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2194 * even temporarily, because of RCU lookups. sk_node should also be left as is.
2195 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2196 */
sock_copy(struct sock * nsk,const struct sock * osk)2197 static void sock_copy(struct sock *nsk, const struct sock *osk)
2198 {
2199 const struct proto *prot = READ_ONCE(osk->sk_prot);
2200 #ifdef CONFIG_SECURITY_NETWORK
2201 void *sptr = nsk->sk_security;
2202 #endif
2203
2204 /* If we move sk_tx_queue_mapping out of the private section,
2205 * we must check if sk_tx_queue_clear() is called after
2206 * sock_copy() in sk_clone_lock().
2207 */
2208 BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2209 offsetof(struct sock, sk_dontcopy_begin) ||
2210 offsetof(struct sock, sk_tx_queue_mapping) >=
2211 offsetof(struct sock, sk_dontcopy_end));
2212
2213 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2214
2215 unsafe_memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2216 prot->obj_size - offsetof(struct sock, sk_dontcopy_end),
2217 /* alloc is larger than struct, see sk_prot_alloc() */);
2218
2219 #ifdef CONFIG_SECURITY_NETWORK
2220 nsk->sk_security = sptr;
2221 security_sk_clone(osk, nsk);
2222 #endif
2223 }
2224
sk_prot_alloc(struct proto * prot,gfp_t priority,int family)2225 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2226 int family)
2227 {
2228 struct sock *sk;
2229 struct kmem_cache *slab;
2230
2231 slab = prot->slab;
2232 if (slab != NULL) {
2233 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2234 if (!sk)
2235 return sk;
2236 if (want_init_on_alloc(priority))
2237 sk_prot_clear_nulls(sk, prot->obj_size);
2238 } else
2239 sk = kmalloc(prot->obj_size, priority);
2240
2241 if (sk != NULL) {
2242 if (security_sk_alloc(sk, family, priority))
2243 goto out_free;
2244
2245 if (!try_module_get(prot->owner))
2246 goto out_free_sec;
2247 }
2248
2249 return sk;
2250
2251 out_free_sec:
2252 security_sk_free(sk);
2253 out_free:
2254 if (slab != NULL)
2255 kmem_cache_free(slab, sk);
2256 else
2257 kfree(sk);
2258 return NULL;
2259 }
2260
sk_prot_free(struct proto * prot,struct sock * sk)2261 static void sk_prot_free(struct proto *prot, struct sock *sk)
2262 {
2263 struct kmem_cache *slab;
2264 struct module *owner;
2265
2266 owner = prot->owner;
2267 slab = prot->slab;
2268
2269 cgroup_sk_free(&sk->sk_cgrp_data);
2270 mem_cgroup_sk_free(sk);
2271 security_sk_free(sk);
2272
2273 sk_owner_put(sk);
2274
2275 if (slab != NULL)
2276 kmem_cache_free(slab, sk);
2277 else
2278 kfree(sk);
2279 module_put(owner);
2280 }
2281
2282 /**
2283 * sk_alloc - All socket objects are allocated here
2284 * @net: the applicable net namespace
2285 * @family: protocol family
2286 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2287 * @prot: struct proto associated with this new sock instance
2288 * @kern: is this to be a kernel socket?
2289 */
sk_alloc(struct net * net,int family,gfp_t priority,struct proto * prot,int kern)2290 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2291 struct proto *prot, int kern)
2292 {
2293 struct sock *sk;
2294
2295 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2296 if (sk) {
2297 sk->sk_family = family;
2298 /*
2299 * See comment in struct sock definition to understand
2300 * why we need sk_prot_creator -acme
2301 */
2302 sk->sk_prot = sk->sk_prot_creator = prot;
2303 sk->sk_kern_sock = kern;
2304 sock_lock_init(sk);
2305 sk->sk_net_refcnt = kern ? 0 : 1;
2306 if (likely(sk->sk_net_refcnt)) {
2307 get_net_track(net, &sk->ns_tracker, priority);
2308 sock_inuse_add(net, 1);
2309 } else {
2310 net_passive_inc(net);
2311 __netns_tracker_alloc(net, &sk->ns_tracker,
2312 false, priority);
2313 }
2314
2315 sock_net_set(sk, net);
2316 refcount_set(&sk->sk_wmem_alloc, 1);
2317
2318 mem_cgroup_sk_alloc(sk);
2319 cgroup_sk_alloc(&sk->sk_cgrp_data);
2320 sock_update_classid(&sk->sk_cgrp_data);
2321 sock_update_netprioidx(&sk->sk_cgrp_data);
2322 sk_tx_queue_clear(sk);
2323 }
2324
2325 return sk;
2326 }
2327 EXPORT_SYMBOL(sk_alloc);
2328
2329 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2330 * grace period. This is the case for UDP sockets and TCP listeners.
2331 */
__sk_destruct(struct rcu_head * head)2332 static void __sk_destruct(struct rcu_head *head)
2333 {
2334 struct sock *sk = container_of(head, struct sock, sk_rcu);
2335 struct net *net = sock_net(sk);
2336 struct sk_filter *filter;
2337
2338 if (sk->sk_destruct)
2339 sk->sk_destruct(sk);
2340
2341 filter = rcu_dereference_check(sk->sk_filter,
2342 refcount_read(&sk->sk_wmem_alloc) == 0);
2343 if (filter) {
2344 sk_filter_uncharge(sk, filter);
2345 RCU_INIT_POINTER(sk->sk_filter, NULL);
2346 }
2347
2348 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2349
2350 #ifdef CONFIG_BPF_SYSCALL
2351 bpf_sk_storage_free(sk);
2352 #endif
2353
2354 if (atomic_read(&sk->sk_omem_alloc))
2355 pr_debug("%s: optmem leakage (%d bytes) detected\n",
2356 __func__, atomic_read(&sk->sk_omem_alloc));
2357
2358 if (sk->sk_frag.page) {
2359 put_page(sk->sk_frag.page);
2360 sk->sk_frag.page = NULL;
2361 }
2362
2363 /* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2364 put_cred(sk->sk_peer_cred);
2365 put_pid(sk->sk_peer_pid);
2366
2367 if (likely(sk->sk_net_refcnt)) {
2368 put_net_track(net, &sk->ns_tracker);
2369 } else {
2370 __netns_tracker_free(net, &sk->ns_tracker, false);
2371 net_passive_dec(net);
2372 }
2373 sk_prot_free(sk->sk_prot_creator, sk);
2374 }
2375
sk_net_refcnt_upgrade(struct sock * sk)2376 void sk_net_refcnt_upgrade(struct sock *sk)
2377 {
2378 struct net *net = sock_net(sk);
2379
2380 WARN_ON_ONCE(sk->sk_net_refcnt);
2381 __netns_tracker_free(net, &sk->ns_tracker, false);
2382 net_passive_dec(net);
2383 sk->sk_net_refcnt = 1;
2384 get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
2385 sock_inuse_add(net, 1);
2386 }
2387 EXPORT_SYMBOL_GPL(sk_net_refcnt_upgrade);
2388
sk_destruct(struct sock * sk)2389 void sk_destruct(struct sock *sk)
2390 {
2391 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2392
2393 if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2394 reuseport_detach_sock(sk);
2395 use_call_rcu = true;
2396 }
2397
2398 if (use_call_rcu)
2399 call_rcu(&sk->sk_rcu, __sk_destruct);
2400 else
2401 __sk_destruct(&sk->sk_rcu);
2402 }
2403
__sk_free(struct sock * sk)2404 static void __sk_free(struct sock *sk)
2405 {
2406 if (likely(sk->sk_net_refcnt))
2407 sock_inuse_add(sock_net(sk), -1);
2408
2409 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2410 sock_diag_broadcast_destroy(sk);
2411 else
2412 sk_destruct(sk);
2413 }
2414
sk_free(struct sock * sk)2415 void sk_free(struct sock *sk)
2416 {
2417 /*
2418 * We subtract one from sk_wmem_alloc and can know if
2419 * some packets are still in some tx queue.
2420 * If not null, sock_wfree() will call __sk_free(sk) later
2421 */
2422 if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2423 __sk_free(sk);
2424 }
2425 EXPORT_SYMBOL(sk_free);
2426
sk_init_common(struct sock * sk)2427 static void sk_init_common(struct sock *sk)
2428 {
2429 skb_queue_head_init(&sk->sk_receive_queue);
2430 skb_queue_head_init(&sk->sk_write_queue);
2431 skb_queue_head_init(&sk->sk_error_queue);
2432
2433 rwlock_init(&sk->sk_callback_lock);
2434 lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2435 af_rlock_keys + sk->sk_family,
2436 af_family_rlock_key_strings[sk->sk_family]);
2437 lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2438 af_wlock_keys + sk->sk_family,
2439 af_family_wlock_key_strings[sk->sk_family]);
2440 lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2441 af_elock_keys + sk->sk_family,
2442 af_family_elock_key_strings[sk->sk_family]);
2443 if (sk->sk_kern_sock)
2444 lockdep_set_class_and_name(&sk->sk_callback_lock,
2445 af_kern_callback_keys + sk->sk_family,
2446 af_family_kern_clock_key_strings[sk->sk_family]);
2447 else
2448 lockdep_set_class_and_name(&sk->sk_callback_lock,
2449 af_callback_keys + sk->sk_family,
2450 af_family_clock_key_strings[sk->sk_family]);
2451 }
2452
2453 /**
2454 * sk_clone_lock - clone a socket, and lock its clone
2455 * @sk: the socket to clone
2456 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2457 *
2458 * Caller must unlock socket even in error path (bh_unlock_sock(newsk))
2459 */
sk_clone_lock(const struct sock * sk,const gfp_t priority)2460 struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority)
2461 {
2462 struct proto *prot = READ_ONCE(sk->sk_prot);
2463 struct sk_filter *filter;
2464 bool is_charged = true;
2465 struct sock *newsk;
2466
2467 newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2468 if (!newsk)
2469 goto out;
2470
2471 sock_copy(newsk, sk);
2472
2473 newsk->sk_prot_creator = prot;
2474
2475 /* SANITY */
2476 if (likely(newsk->sk_net_refcnt)) {
2477 get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2478 sock_inuse_add(sock_net(newsk), 1);
2479 } else {
2480 /* Kernel sockets are not elevating the struct net refcount.
2481 * Instead, use a tracker to more easily detect if a layer
2482 * is not properly dismantling its kernel sockets at netns
2483 * destroy time.
2484 */
2485 net_passive_inc(sock_net(newsk));
2486 __netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2487 false, priority);
2488 }
2489 sk_node_init(&newsk->sk_node);
2490 sock_lock_init(newsk);
2491 bh_lock_sock(newsk);
2492 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
2493 newsk->sk_backlog.len = 0;
2494
2495 atomic_set(&newsk->sk_rmem_alloc, 0);
2496
2497 /* sk_wmem_alloc set to one (see sk_free() and sock_wfree()) */
2498 refcount_set(&newsk->sk_wmem_alloc, 1);
2499
2500 atomic_set(&newsk->sk_omem_alloc, 0);
2501 sk_init_common(newsk);
2502
2503 newsk->sk_dst_cache = NULL;
2504 newsk->sk_dst_pending_confirm = 0;
2505 newsk->sk_wmem_queued = 0;
2506 newsk->sk_forward_alloc = 0;
2507 newsk->sk_reserved_mem = 0;
2508 DEBUG_NET_WARN_ON_ONCE(newsk->sk_drop_counters);
2509 sk_drops_reset(newsk);
2510 newsk->sk_send_head = NULL;
2511 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2512 atomic_set(&newsk->sk_zckey, 0);
2513
2514 sock_reset_flag(newsk, SOCK_DONE);
2515
2516 #ifdef CONFIG_MEMCG
2517 /* sk->sk_memcg will be populated at accept() time */
2518 newsk->sk_memcg = NULL;
2519 #endif
2520
2521 cgroup_sk_clone(&newsk->sk_cgrp_data);
2522
2523 rcu_read_lock();
2524 filter = rcu_dereference(sk->sk_filter);
2525 if (filter != NULL)
2526 /* though it's an empty new sock, the charging may fail
2527 * if sysctl_optmem_max was changed between creation of
2528 * original socket and cloning
2529 */
2530 is_charged = sk_filter_charge(newsk, filter);
2531 RCU_INIT_POINTER(newsk->sk_filter, filter);
2532 rcu_read_unlock();
2533
2534 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2535 /* We need to make sure that we don't uncharge the new
2536 * socket if we couldn't charge it in the first place
2537 * as otherwise we uncharge the parent's filter.
2538 */
2539 if (!is_charged)
2540 RCU_INIT_POINTER(newsk->sk_filter, NULL);
2541
2542 goto free;
2543 }
2544
2545 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2546
2547 if (bpf_sk_storage_clone(sk, newsk))
2548 goto free;
2549
2550 /* Clear sk_user_data if parent had the pointer tagged
2551 * as not suitable for copying when cloning.
2552 */
2553 if (sk_user_data_is_nocopy(newsk))
2554 newsk->sk_user_data = NULL;
2555
2556 newsk->sk_err = 0;
2557 newsk->sk_err_soft = 0;
2558 newsk->sk_priority = 0;
2559 newsk->sk_incoming_cpu = raw_smp_processor_id();
2560
2561 /* Before updating sk_refcnt, we must commit prior changes to memory
2562 * (Documentation/RCU/rculist_nulls.rst for details)
2563 */
2564 smp_wmb();
2565 refcount_set(&newsk->sk_refcnt, 2);
2566
2567 sk_set_socket(newsk, NULL);
2568 sk_tx_queue_clear(newsk);
2569 RCU_INIT_POINTER(newsk->sk_wq, NULL);
2570
2571 if (newsk->sk_prot->sockets_allocated)
2572 sk_sockets_allocated_inc(newsk);
2573
2574 if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2575 net_enable_timestamp();
2576 out:
2577 return newsk;
2578 free:
2579 /* It is still raw copy of parent, so invalidate
2580 * destructor and make plain sk_free()
2581 */
2582 newsk->sk_destruct = NULL;
2583 bh_unlock_sock(newsk);
2584 sk_free(newsk);
2585 newsk = NULL;
2586 goto out;
2587 }
2588 EXPORT_SYMBOL_GPL(sk_clone_lock);
2589
sk_dst_gso_max_size(struct sock * sk,const struct net_device * dev)2590 static u32 sk_dst_gso_max_size(struct sock *sk, const struct net_device *dev)
2591 {
2592 bool is_ipv6 = false;
2593 u32 max_size;
2594
2595 #if IS_ENABLED(CONFIG_IPV6)
2596 is_ipv6 = (sk->sk_family == AF_INET6 &&
2597 !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2598 #endif
2599 /* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2600 max_size = is_ipv6 ? READ_ONCE(dev->gso_max_size) :
2601 READ_ONCE(dev->gso_ipv4_max_size);
2602 if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2603 max_size = GSO_LEGACY_MAX_SIZE;
2604
2605 return max_size - (MAX_TCP_HEADER + 1);
2606 }
2607
sk_setup_caps(struct sock * sk,struct dst_entry * dst)2608 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2609 {
2610 const struct net_device *dev;
2611 u32 max_segs = 1;
2612
2613 rcu_read_lock();
2614 dev = dst_dev_rcu(dst);
2615 sk->sk_route_caps = dev->features;
2616 if (sk_is_tcp(sk)) {
2617 struct inet_connection_sock *icsk = inet_csk(sk);
2618
2619 sk->sk_route_caps |= NETIF_F_GSO;
2620 icsk->icsk_ack.dst_quick_ack = dst_metric(dst, RTAX_QUICKACK);
2621 }
2622 if (sk->sk_route_caps & NETIF_F_GSO)
2623 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2624 if (unlikely(sk->sk_gso_disabled))
2625 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2626 if (sk_can_gso(sk)) {
2627 if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2628 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2629 } else {
2630 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2631 sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dev);
2632 /* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2633 max_segs = max_t(u32, READ_ONCE(dev->gso_max_segs), 1);
2634 }
2635 }
2636 sk->sk_gso_max_segs = max_segs;
2637 sk_dst_set(sk, dst);
2638 rcu_read_unlock();
2639 }
2640 EXPORT_SYMBOL_GPL(sk_setup_caps);
2641
2642 /*
2643 * Simple resource managers for sockets.
2644 */
2645
2646
2647 /*
2648 * Write buffer destructor automatically called from kfree_skb.
2649 */
sock_wfree(struct sk_buff * skb)2650 void sock_wfree(struct sk_buff *skb)
2651 {
2652 struct sock *sk = skb->sk;
2653 unsigned int len = skb->truesize;
2654 bool free;
2655
2656 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2657 if (sock_flag(sk, SOCK_RCU_FREE) &&
2658 sk->sk_write_space == sock_def_write_space) {
2659 rcu_read_lock();
2660 free = refcount_sub_and_test(len, &sk->sk_wmem_alloc);
2661 sock_def_write_space_wfree(sk);
2662 rcu_read_unlock();
2663 if (unlikely(free))
2664 __sk_free(sk);
2665 return;
2666 }
2667
2668 /*
2669 * Keep a reference on sk_wmem_alloc, this will be released
2670 * after sk_write_space() call
2671 */
2672 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2673 sk->sk_write_space(sk);
2674 len = 1;
2675 }
2676 /*
2677 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2678 * could not do because of in-flight packets
2679 */
2680 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2681 __sk_free(sk);
2682 }
2683 EXPORT_SYMBOL(sock_wfree);
2684
2685 /* This variant of sock_wfree() is used by TCP,
2686 * since it sets SOCK_USE_WRITE_QUEUE.
2687 */
__sock_wfree(struct sk_buff * skb)2688 void __sock_wfree(struct sk_buff *skb)
2689 {
2690 struct sock *sk = skb->sk;
2691
2692 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2693 __sk_free(sk);
2694 }
2695
skb_set_owner_w(struct sk_buff * skb,struct sock * sk)2696 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2697 {
2698 skb_orphan(skb);
2699 #ifdef CONFIG_INET
2700 if (unlikely(!sk_fullsock(sk)))
2701 return skb_set_owner_edemux(skb, sk);
2702 #endif
2703 skb->sk = sk;
2704 skb->destructor = sock_wfree;
2705 skb_set_hash_from_sk(skb, sk);
2706 /*
2707 * We used to take a refcount on sk, but following operation
2708 * is enough to guarantee sk_free() won't free this sock until
2709 * all in-flight packets are completed
2710 */
2711 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
2712 }
2713 EXPORT_SYMBOL(skb_set_owner_w);
2714
can_skb_orphan_partial(const struct sk_buff * skb)2715 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2716 {
2717 /* Drivers depend on in-order delivery for crypto offload,
2718 * partial orphan breaks out-of-order-OK logic.
2719 */
2720 if (skb_is_decrypted(skb))
2721 return false;
2722
2723 return (skb->destructor == sock_wfree ||
2724 (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2725 }
2726
2727 /* This helper is used by netem, as it can hold packets in its
2728 * delay queue. We want to allow the owner socket to send more
2729 * packets, as if they were already TX completed by a typical driver.
2730 * But we also want to keep skb->sk set because some packet schedulers
2731 * rely on it (sch_fq for example).
2732 */
skb_orphan_partial(struct sk_buff * skb)2733 void skb_orphan_partial(struct sk_buff *skb)
2734 {
2735 if (skb_is_tcp_pure_ack(skb))
2736 return;
2737
2738 if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2739 return;
2740
2741 skb_orphan(skb);
2742 }
2743 EXPORT_SYMBOL(skb_orphan_partial);
2744
2745 /*
2746 * Read buffer destructor automatically called from kfree_skb.
2747 */
sock_rfree(struct sk_buff * skb)2748 void sock_rfree(struct sk_buff *skb)
2749 {
2750 struct sock *sk = skb->sk;
2751 unsigned int len = skb->truesize;
2752
2753 atomic_sub(len, &sk->sk_rmem_alloc);
2754 sk_mem_uncharge(sk, len);
2755 }
2756 EXPORT_SYMBOL(sock_rfree);
2757
2758 /*
2759 * Buffer destructor for skbs that are not used directly in read or write
2760 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2761 */
sock_efree(struct sk_buff * skb)2762 void sock_efree(struct sk_buff *skb)
2763 {
2764 sock_put(skb->sk);
2765 }
2766 EXPORT_SYMBOL(sock_efree);
2767
2768 /* Buffer destructor for prefetch/receive path where reference count may
2769 * not be held, e.g. for listen sockets.
2770 */
2771 #ifdef CONFIG_INET
sock_pfree(struct sk_buff * skb)2772 void sock_pfree(struct sk_buff *skb)
2773 {
2774 struct sock *sk = skb->sk;
2775
2776 if (!sk_is_refcounted(sk))
2777 return;
2778
2779 if (sk->sk_state == TCP_NEW_SYN_RECV && inet_reqsk(sk)->syncookie) {
2780 inet_reqsk(sk)->rsk_listener = NULL;
2781 reqsk_free(inet_reqsk(sk));
2782 return;
2783 }
2784
2785 sock_gen_put(sk);
2786 }
2787 EXPORT_SYMBOL(sock_pfree);
2788 #endif /* CONFIG_INET */
2789
2790 /*
2791 * Allocate a skb from the socket's send buffer.
2792 */
sock_wmalloc(struct sock * sk,unsigned long size,int force,gfp_t priority)2793 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2794 gfp_t priority)
2795 {
2796 if (force ||
2797 refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2798 struct sk_buff *skb = alloc_skb(size, priority);
2799
2800 if (skb) {
2801 skb_set_owner_w(skb, sk);
2802 return skb;
2803 }
2804 }
2805 return NULL;
2806 }
2807 EXPORT_SYMBOL(sock_wmalloc);
2808
sock_ofree(struct sk_buff * skb)2809 static void sock_ofree(struct sk_buff *skb)
2810 {
2811 struct sock *sk = skb->sk;
2812
2813 atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2814 }
2815
sock_omalloc(struct sock * sk,unsigned long size,gfp_t priority)2816 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2817 gfp_t priority)
2818 {
2819 struct sk_buff *skb;
2820
2821 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2822 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2823 READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2824 return NULL;
2825
2826 skb = alloc_skb(size, priority);
2827 if (!skb)
2828 return NULL;
2829
2830 atomic_add(skb->truesize, &sk->sk_omem_alloc);
2831 skb->sk = sk;
2832 skb->destructor = sock_ofree;
2833 return skb;
2834 }
2835
2836 /*
2837 * Allocate a memory block from the socket's option memory buffer.
2838 */
sock_kmalloc(struct sock * sk,int size,gfp_t priority)2839 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2840 {
2841 int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2842
2843 if ((unsigned int)size <= optmem_max &&
2844 atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2845 void *mem;
2846 /* First do the add, to avoid the race if kmalloc
2847 * might sleep.
2848 */
2849 atomic_add(size, &sk->sk_omem_alloc);
2850 mem = kmalloc(size, priority);
2851 if (mem)
2852 return mem;
2853 atomic_sub(size, &sk->sk_omem_alloc);
2854 }
2855 return NULL;
2856 }
2857 EXPORT_SYMBOL(sock_kmalloc);
2858
2859 /*
2860 * Duplicate the input "src" memory block using the socket's
2861 * option memory buffer.
2862 */
sock_kmemdup(struct sock * sk,const void * src,int size,gfp_t priority)2863 void *sock_kmemdup(struct sock *sk, const void *src,
2864 int size, gfp_t priority)
2865 {
2866 void *mem;
2867
2868 mem = sock_kmalloc(sk, size, priority);
2869 if (mem)
2870 memcpy(mem, src, size);
2871 return mem;
2872 }
2873 EXPORT_SYMBOL(sock_kmemdup);
2874
2875 /* Free an option memory block. Note, we actually want the inline
2876 * here as this allows gcc to detect the nullify and fold away the
2877 * condition entirely.
2878 */
__sock_kfree_s(struct sock * sk,void * mem,int size,const bool nullify)2879 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2880 const bool nullify)
2881 {
2882 if (WARN_ON_ONCE(!mem))
2883 return;
2884 if (nullify)
2885 kfree_sensitive(mem);
2886 else
2887 kfree(mem);
2888 atomic_sub(size, &sk->sk_omem_alloc);
2889 }
2890
sock_kfree_s(struct sock * sk,void * mem,int size)2891 void sock_kfree_s(struct sock *sk, void *mem, int size)
2892 {
2893 __sock_kfree_s(sk, mem, size, false);
2894 }
2895 EXPORT_SYMBOL(sock_kfree_s);
2896
sock_kzfree_s(struct sock * sk,void * mem,int size)2897 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2898 {
2899 __sock_kfree_s(sk, mem, size, true);
2900 }
2901 EXPORT_SYMBOL(sock_kzfree_s);
2902
2903 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2904 I think, these locks should be removed for datagram sockets.
2905 */
sock_wait_for_wmem(struct sock * sk,long timeo)2906 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2907 {
2908 DEFINE_WAIT(wait);
2909
2910 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2911 for (;;) {
2912 if (!timeo)
2913 break;
2914 if (signal_pending(current))
2915 break;
2916 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2917 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2918 if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2919 break;
2920 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2921 break;
2922 if (READ_ONCE(sk->sk_err))
2923 break;
2924 timeo = schedule_timeout(timeo);
2925 }
2926 finish_wait(sk_sleep(sk), &wait);
2927 return timeo;
2928 }
2929
2930
2931 /*
2932 * Generic send/receive buffer handlers
2933 */
2934
sock_alloc_send_pskb(struct sock * sk,unsigned long header_len,unsigned long data_len,int noblock,int * errcode,int max_page_order)2935 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2936 unsigned long data_len, int noblock,
2937 int *errcode, int max_page_order)
2938 {
2939 struct sk_buff *skb;
2940 long timeo;
2941 int err;
2942
2943 timeo = sock_sndtimeo(sk, noblock);
2944 for (;;) {
2945 err = sock_error(sk);
2946 if (err != 0)
2947 goto failure;
2948
2949 err = -EPIPE;
2950 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2951 goto failure;
2952
2953 if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2954 break;
2955
2956 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2957 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2958 err = -EAGAIN;
2959 if (!timeo)
2960 goto failure;
2961 if (signal_pending(current))
2962 goto interrupted;
2963 timeo = sock_wait_for_wmem(sk, timeo);
2964 }
2965 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
2966 errcode, sk->sk_allocation);
2967 if (skb)
2968 skb_set_owner_w(skb, sk);
2969 return skb;
2970
2971 interrupted:
2972 err = sock_intr_errno(timeo);
2973 failure:
2974 *errcode = err;
2975 return NULL;
2976 }
2977 EXPORT_SYMBOL(sock_alloc_send_pskb);
2978
__sock_cmsg_send(struct sock * sk,struct cmsghdr * cmsg,struct sockcm_cookie * sockc)2979 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
2980 struct sockcm_cookie *sockc)
2981 {
2982 u32 tsflags;
2983
2984 BUILD_BUG_ON(SOF_TIMESTAMPING_LAST == (1 << 31));
2985
2986 switch (cmsg->cmsg_type) {
2987 case SO_MARK:
2988 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
2989 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
2990 return -EPERM;
2991 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2992 return -EINVAL;
2993 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
2994 break;
2995 case SO_TIMESTAMPING_OLD:
2996 case SO_TIMESTAMPING_NEW:
2997 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
2998 return -EINVAL;
2999
3000 tsflags = *(u32 *)CMSG_DATA(cmsg);
3001 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
3002 return -EINVAL;
3003
3004 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
3005 sockc->tsflags |= tsflags;
3006 break;
3007 case SCM_TXTIME:
3008 if (!sock_flag(sk, SOCK_TXTIME))
3009 return -EINVAL;
3010 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
3011 return -EINVAL;
3012 sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
3013 break;
3014 case SCM_TS_OPT_ID:
3015 if (sk_is_tcp(sk))
3016 return -EINVAL;
3017 tsflags = READ_ONCE(sk->sk_tsflags);
3018 if (!(tsflags & SOF_TIMESTAMPING_OPT_ID))
3019 return -EINVAL;
3020 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3021 return -EINVAL;
3022 sockc->ts_opt_id = *(u32 *)CMSG_DATA(cmsg);
3023 sockc->tsflags |= SOCKCM_FLAG_TS_OPT_ID;
3024 break;
3025 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
3026 case SCM_RIGHTS:
3027 case SCM_CREDENTIALS:
3028 break;
3029 case SO_PRIORITY:
3030 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3031 return -EINVAL;
3032 if (!sk_set_prio_allowed(sk, *(u32 *)CMSG_DATA(cmsg)))
3033 return -EPERM;
3034 sockc->priority = *(u32 *)CMSG_DATA(cmsg);
3035 break;
3036 case SCM_DEVMEM_DMABUF:
3037 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3038 return -EINVAL;
3039 sockc->dmabuf_id = *(u32 *)CMSG_DATA(cmsg);
3040 break;
3041 default:
3042 return -EINVAL;
3043 }
3044 return 0;
3045 }
3046 EXPORT_SYMBOL(__sock_cmsg_send);
3047
sock_cmsg_send(struct sock * sk,struct msghdr * msg,struct sockcm_cookie * sockc)3048 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
3049 struct sockcm_cookie *sockc)
3050 {
3051 struct cmsghdr *cmsg;
3052 int ret;
3053
3054 for_each_cmsghdr(cmsg, msg) {
3055 if (!CMSG_OK(msg, cmsg))
3056 return -EINVAL;
3057 if (cmsg->cmsg_level != SOL_SOCKET)
3058 continue;
3059 ret = __sock_cmsg_send(sk, cmsg, sockc);
3060 if (ret)
3061 return ret;
3062 }
3063 return 0;
3064 }
3065 EXPORT_SYMBOL(sock_cmsg_send);
3066
sk_enter_memory_pressure(struct sock * sk)3067 static void sk_enter_memory_pressure(struct sock *sk)
3068 {
3069 if (!sk->sk_prot->enter_memory_pressure)
3070 return;
3071
3072 sk->sk_prot->enter_memory_pressure(sk);
3073 }
3074
sk_leave_memory_pressure(struct sock * sk)3075 static void sk_leave_memory_pressure(struct sock *sk)
3076 {
3077 if (sk->sk_prot->leave_memory_pressure) {
3078 INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
3079 tcp_leave_memory_pressure, sk);
3080 } else {
3081 unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
3082
3083 if (memory_pressure && READ_ONCE(*memory_pressure))
3084 WRITE_ONCE(*memory_pressure, 0);
3085 }
3086 }
3087
3088 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
3089
3090 /**
3091 * skb_page_frag_refill - check that a page_frag contains enough room
3092 * @sz: minimum size of the fragment we want to get
3093 * @pfrag: pointer to page_frag
3094 * @gfp: priority for memory allocation
3095 *
3096 * Note: While this allocator tries to use high order pages, there is
3097 * no guarantee that allocations succeed. Therefore, @sz MUST be
3098 * less or equal than PAGE_SIZE.
3099 */
skb_page_frag_refill(unsigned int sz,struct page_frag * pfrag,gfp_t gfp)3100 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
3101 {
3102 if (pfrag->page) {
3103 if (page_ref_count(pfrag->page) == 1) {
3104 pfrag->offset = 0;
3105 return true;
3106 }
3107 if (pfrag->offset + sz <= pfrag->size)
3108 return true;
3109 put_page(pfrag->page);
3110 }
3111
3112 pfrag->offset = 0;
3113 if (SKB_FRAG_PAGE_ORDER &&
3114 !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
3115 /* Avoid direct reclaim but allow kswapd to wake */
3116 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
3117 __GFP_COMP | __GFP_NOWARN |
3118 __GFP_NORETRY,
3119 SKB_FRAG_PAGE_ORDER);
3120 if (likely(pfrag->page)) {
3121 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
3122 return true;
3123 }
3124 }
3125 pfrag->page = alloc_page(gfp);
3126 if (likely(pfrag->page)) {
3127 pfrag->size = PAGE_SIZE;
3128 return true;
3129 }
3130 return false;
3131 }
3132 EXPORT_SYMBOL(skb_page_frag_refill);
3133
sk_page_frag_refill(struct sock * sk,struct page_frag * pfrag)3134 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
3135 {
3136 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
3137 return true;
3138
3139 sk_enter_memory_pressure(sk);
3140 sk_stream_moderate_sndbuf(sk);
3141 return false;
3142 }
3143 EXPORT_SYMBOL(sk_page_frag_refill);
3144
__lock_sock(struct sock * sk)3145 void __lock_sock(struct sock *sk)
3146 __releases(&sk->sk_lock.slock)
3147 __acquires(&sk->sk_lock.slock)
3148 {
3149 DEFINE_WAIT(wait);
3150
3151 for (;;) {
3152 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
3153 TASK_UNINTERRUPTIBLE);
3154 spin_unlock_bh(&sk->sk_lock.slock);
3155 schedule();
3156 spin_lock_bh(&sk->sk_lock.slock);
3157 if (!sock_owned_by_user(sk))
3158 break;
3159 }
3160 finish_wait(&sk->sk_lock.wq, &wait);
3161 }
3162
__release_sock(struct sock * sk)3163 void __release_sock(struct sock *sk)
3164 __releases(&sk->sk_lock.slock)
3165 __acquires(&sk->sk_lock.slock)
3166 {
3167 struct sk_buff *skb, *next;
3168 int nb = 0;
3169
3170 while ((skb = sk->sk_backlog.head) != NULL) {
3171 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
3172
3173 spin_unlock_bh(&sk->sk_lock.slock);
3174
3175 while (1) {
3176 next = skb->next;
3177 prefetch(next);
3178 DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
3179 skb_mark_not_on_list(skb);
3180 sk_backlog_rcv(sk, skb);
3181
3182 skb = next;
3183 if (!skb)
3184 break;
3185
3186 if (!(++nb & 15))
3187 cond_resched();
3188 }
3189
3190 spin_lock_bh(&sk->sk_lock.slock);
3191 }
3192
3193 /*
3194 * Doing the zeroing here guarantee we can not loop forever
3195 * while a wild producer attempts to flood us.
3196 */
3197 sk->sk_backlog.len = 0;
3198 }
3199
__sk_flush_backlog(struct sock * sk)3200 void __sk_flush_backlog(struct sock *sk)
3201 {
3202 spin_lock_bh(&sk->sk_lock.slock);
3203 __release_sock(sk);
3204
3205 if (sk->sk_prot->release_cb)
3206 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3207 tcp_release_cb, sk);
3208
3209 spin_unlock_bh(&sk->sk_lock.slock);
3210 }
3211 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3212
3213 /**
3214 * sk_wait_data - wait for data to arrive at sk_receive_queue
3215 * @sk: sock to wait on
3216 * @timeo: for how long
3217 * @skb: last skb seen on sk_receive_queue
3218 *
3219 * Now socket state including sk->sk_err is changed only under lock,
3220 * hence we may omit checks after joining wait queue.
3221 * We check receive queue before schedule() only as optimization;
3222 * it is very likely that release_sock() added new data.
3223 */
sk_wait_data(struct sock * sk,long * timeo,const struct sk_buff * skb)3224 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3225 {
3226 DEFINE_WAIT_FUNC(wait, woken_wake_function);
3227 int rc;
3228
3229 add_wait_queue(sk_sleep(sk), &wait);
3230 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3231 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3232 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3233 remove_wait_queue(sk_sleep(sk), &wait);
3234 return rc;
3235 }
3236 EXPORT_SYMBOL(sk_wait_data);
3237
3238 /**
3239 * __sk_mem_raise_allocated - increase memory_allocated
3240 * @sk: socket
3241 * @size: memory size to allocate
3242 * @amt: pages to allocate
3243 * @kind: allocation type
3244 *
3245 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3246 *
3247 * Unlike the globally shared limits among the sockets under same protocol,
3248 * consuming the budget of a memcg won't have direct effect on other ones.
3249 * So be optimistic about memcg's tolerance, and leave the callers to decide
3250 * whether or not to raise allocated through sk_under_memory_pressure() or
3251 * its variants.
3252 */
__sk_mem_raise_allocated(struct sock * sk,int size,int amt,int kind)3253 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3254 {
3255 bool memcg_enabled = false, charged = false;
3256 struct proto *prot = sk->sk_prot;
3257 long allocated;
3258
3259 sk_memory_allocated_add(sk, amt);
3260 allocated = sk_memory_allocated(sk);
3261
3262 if (mem_cgroup_sk_enabled(sk)) {
3263 memcg_enabled = true;
3264 charged = mem_cgroup_sk_charge(sk, amt, gfp_memcg_charge());
3265 if (!charged)
3266 goto suppress_allocation;
3267 }
3268
3269 /* Under limit. */
3270 if (allocated <= sk_prot_mem_limits(sk, 0)) {
3271 sk_leave_memory_pressure(sk);
3272 return 1;
3273 }
3274
3275 /* Under pressure. */
3276 if (allocated > sk_prot_mem_limits(sk, 1))
3277 sk_enter_memory_pressure(sk);
3278
3279 /* Over hard limit. */
3280 if (allocated > sk_prot_mem_limits(sk, 2))
3281 goto suppress_allocation;
3282
3283 /* Guarantee minimum buffer size under pressure (either global
3284 * or memcg) to make sure features described in RFC 7323 (TCP
3285 * Extensions for High Performance) work properly.
3286 *
3287 * This rule does NOT stand when exceeds global or memcg's hard
3288 * limit, or else a DoS attack can be taken place by spawning
3289 * lots of sockets whose usage are under minimum buffer size.
3290 */
3291 if (kind == SK_MEM_RECV) {
3292 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3293 return 1;
3294
3295 } else { /* SK_MEM_SEND */
3296 int wmem0 = sk_get_wmem0(sk, prot);
3297
3298 if (sk->sk_type == SOCK_STREAM) {
3299 if (sk->sk_wmem_queued < wmem0)
3300 return 1;
3301 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3302 return 1;
3303 }
3304 }
3305
3306 if (sk_has_memory_pressure(sk)) {
3307 u64 alloc;
3308
3309 /* The following 'average' heuristic is within the
3310 * scope of global accounting, so it only makes
3311 * sense for global memory pressure.
3312 */
3313 if (!sk_under_global_memory_pressure(sk))
3314 return 1;
3315
3316 /* Try to be fair among all the sockets under global
3317 * pressure by allowing the ones that below average
3318 * usage to raise.
3319 */
3320 alloc = sk_sockets_allocated_read_positive(sk);
3321 if (sk_prot_mem_limits(sk, 2) > alloc *
3322 sk_mem_pages(sk->sk_wmem_queued +
3323 atomic_read(&sk->sk_rmem_alloc) +
3324 sk->sk_forward_alloc))
3325 return 1;
3326 }
3327
3328 suppress_allocation:
3329
3330 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3331 sk_stream_moderate_sndbuf(sk);
3332
3333 /* Fail only if socket is _under_ its sndbuf.
3334 * In this case we cannot block, so that we have to fail.
3335 */
3336 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3337 /* Force charge with __GFP_NOFAIL */
3338 if (memcg_enabled && !charged)
3339 mem_cgroup_sk_charge(sk, amt,
3340 gfp_memcg_charge() | __GFP_NOFAIL);
3341 return 1;
3342 }
3343 }
3344
3345 trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3346
3347 sk_memory_allocated_sub(sk, amt);
3348
3349 if (charged)
3350 mem_cgroup_sk_uncharge(sk, amt);
3351
3352 return 0;
3353 }
3354
3355 /**
3356 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3357 * @sk: socket
3358 * @size: memory size to allocate
3359 * @kind: allocation type
3360 *
3361 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3362 * rmem allocation. This function assumes that protocols which have
3363 * memory_pressure use sk_wmem_queued as write buffer accounting.
3364 */
__sk_mem_schedule(struct sock * sk,int size,int kind)3365 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3366 {
3367 int ret, amt = sk_mem_pages(size);
3368
3369 sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3370 ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3371 if (!ret)
3372 sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3373 return ret;
3374 }
3375 EXPORT_SYMBOL(__sk_mem_schedule);
3376
3377 /**
3378 * __sk_mem_reduce_allocated - reclaim memory_allocated
3379 * @sk: socket
3380 * @amount: number of quanta
3381 *
3382 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3383 */
__sk_mem_reduce_allocated(struct sock * sk,int amount)3384 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3385 {
3386 sk_memory_allocated_sub(sk, amount);
3387
3388 if (mem_cgroup_sk_enabled(sk))
3389 mem_cgroup_sk_uncharge(sk, amount);
3390
3391 if (sk_under_global_memory_pressure(sk) &&
3392 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3393 sk_leave_memory_pressure(sk);
3394 }
3395
3396 /**
3397 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3398 * @sk: socket
3399 * @amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3400 */
__sk_mem_reclaim(struct sock * sk,int amount)3401 void __sk_mem_reclaim(struct sock *sk, int amount)
3402 {
3403 amount >>= PAGE_SHIFT;
3404 sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3405 __sk_mem_reduce_allocated(sk, amount);
3406 }
3407 EXPORT_SYMBOL(__sk_mem_reclaim);
3408
sk_set_peek_off(struct sock * sk,int val)3409 int sk_set_peek_off(struct sock *sk, int val)
3410 {
3411 WRITE_ONCE(sk->sk_peek_off, val);
3412 return 0;
3413 }
3414 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3415
3416 /*
3417 * Set of default routines for initialising struct proto_ops when
3418 * the protocol does not support a particular function. In certain
3419 * cases where it makes no sense for a protocol to have a "do nothing"
3420 * function, some default processing is provided.
3421 */
3422
sock_no_bind(struct socket * sock,struct sockaddr * saddr,int len)3423 int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len)
3424 {
3425 return -EOPNOTSUPP;
3426 }
3427 EXPORT_SYMBOL(sock_no_bind);
3428
sock_no_connect(struct socket * sock,struct sockaddr * saddr,int len,int flags)3429 int sock_no_connect(struct socket *sock, struct sockaddr *saddr,
3430 int len, int flags)
3431 {
3432 return -EOPNOTSUPP;
3433 }
3434 EXPORT_SYMBOL(sock_no_connect);
3435
sock_no_socketpair(struct socket * sock1,struct socket * sock2)3436 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3437 {
3438 return -EOPNOTSUPP;
3439 }
3440 EXPORT_SYMBOL(sock_no_socketpair);
3441
sock_no_accept(struct socket * sock,struct socket * newsock,struct proto_accept_arg * arg)3442 int sock_no_accept(struct socket *sock, struct socket *newsock,
3443 struct proto_accept_arg *arg)
3444 {
3445 return -EOPNOTSUPP;
3446 }
3447 EXPORT_SYMBOL(sock_no_accept);
3448
sock_no_getname(struct socket * sock,struct sockaddr * saddr,int peer)3449 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3450 int peer)
3451 {
3452 return -EOPNOTSUPP;
3453 }
3454 EXPORT_SYMBOL(sock_no_getname);
3455
sock_no_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)3456 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3457 {
3458 return -EOPNOTSUPP;
3459 }
3460 EXPORT_SYMBOL(sock_no_ioctl);
3461
sock_no_listen(struct socket * sock,int backlog)3462 int sock_no_listen(struct socket *sock, int backlog)
3463 {
3464 return -EOPNOTSUPP;
3465 }
3466 EXPORT_SYMBOL(sock_no_listen);
3467
sock_no_shutdown(struct socket * sock,int how)3468 int sock_no_shutdown(struct socket *sock, int how)
3469 {
3470 return -EOPNOTSUPP;
3471 }
3472 EXPORT_SYMBOL(sock_no_shutdown);
3473
sock_no_sendmsg(struct socket * sock,struct msghdr * m,size_t len)3474 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3475 {
3476 return -EOPNOTSUPP;
3477 }
3478 EXPORT_SYMBOL(sock_no_sendmsg);
3479
sock_no_sendmsg_locked(struct sock * sk,struct msghdr * m,size_t len)3480 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3481 {
3482 return -EOPNOTSUPP;
3483 }
3484 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3485
sock_no_recvmsg(struct socket * sock,struct msghdr * m,size_t len,int flags)3486 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3487 int flags)
3488 {
3489 return -EOPNOTSUPP;
3490 }
3491 EXPORT_SYMBOL(sock_no_recvmsg);
3492
sock_no_mmap(struct file * file,struct socket * sock,struct vm_area_struct * vma)3493 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3494 {
3495 /* Mirror missing mmap method error code */
3496 return -ENODEV;
3497 }
3498 EXPORT_SYMBOL(sock_no_mmap);
3499
3500 /*
3501 * When a file is received (via SCM_RIGHTS, etc), we must bump the
3502 * various sock-based usage counts.
3503 */
__receive_sock(struct file * file)3504 void __receive_sock(struct file *file)
3505 {
3506 struct socket *sock;
3507
3508 sock = sock_from_file(file);
3509 if (sock) {
3510 sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3511 sock_update_classid(&sock->sk->sk_cgrp_data);
3512 }
3513 }
3514
3515 /*
3516 * Default Socket Callbacks
3517 */
3518
sock_def_wakeup(struct sock * sk)3519 static void sock_def_wakeup(struct sock *sk)
3520 {
3521 struct socket_wq *wq;
3522
3523 rcu_read_lock();
3524 wq = rcu_dereference(sk->sk_wq);
3525 if (skwq_has_sleeper(wq))
3526 wake_up_interruptible_all(&wq->wait);
3527 rcu_read_unlock();
3528 }
3529
sock_def_error_report(struct sock * sk)3530 static void sock_def_error_report(struct sock *sk)
3531 {
3532 struct socket_wq *wq;
3533
3534 rcu_read_lock();
3535 wq = rcu_dereference(sk->sk_wq);
3536 if (skwq_has_sleeper(wq))
3537 wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3538 sk_wake_async_rcu(sk, SOCK_WAKE_IO, POLL_ERR);
3539 rcu_read_unlock();
3540 }
3541
sock_def_readable(struct sock * sk)3542 void sock_def_readable(struct sock *sk)
3543 {
3544 struct socket_wq *wq;
3545
3546 trace_sk_data_ready(sk);
3547
3548 rcu_read_lock();
3549 wq = rcu_dereference(sk->sk_wq);
3550 if (skwq_has_sleeper(wq))
3551 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3552 EPOLLRDNORM | EPOLLRDBAND);
3553 sk_wake_async_rcu(sk, SOCK_WAKE_WAITD, POLL_IN);
3554 rcu_read_unlock();
3555 }
3556
sock_def_write_space(struct sock * sk)3557 static void sock_def_write_space(struct sock *sk)
3558 {
3559 struct socket_wq *wq;
3560
3561 rcu_read_lock();
3562
3563 /* Do not wake up a writer until he can make "significant"
3564 * progress. --DaveM
3565 */
3566 if (sock_writeable(sk)) {
3567 wq = rcu_dereference(sk->sk_wq);
3568 if (skwq_has_sleeper(wq))
3569 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3570 EPOLLWRNORM | EPOLLWRBAND);
3571
3572 /* Should agree with poll, otherwise some programs break */
3573 sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3574 }
3575
3576 rcu_read_unlock();
3577 }
3578
3579 /* An optimised version of sock_def_write_space(), should only be called
3580 * for SOCK_RCU_FREE sockets under RCU read section and after putting
3581 * ->sk_wmem_alloc.
3582 */
sock_def_write_space_wfree(struct sock * sk)3583 static void sock_def_write_space_wfree(struct sock *sk)
3584 {
3585 /* Do not wake up a writer until he can make "significant"
3586 * progress. --DaveM
3587 */
3588 if (sock_writeable(sk)) {
3589 struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3590
3591 /* rely on refcount_sub from sock_wfree() */
3592 smp_mb__after_atomic();
3593 if (wq && waitqueue_active(&wq->wait))
3594 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3595 EPOLLWRNORM | EPOLLWRBAND);
3596
3597 /* Should agree with poll, otherwise some programs break */
3598 sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3599 }
3600 }
3601
sock_def_destruct(struct sock * sk)3602 static void sock_def_destruct(struct sock *sk)
3603 {
3604 }
3605
sk_send_sigurg(struct sock * sk)3606 void sk_send_sigurg(struct sock *sk)
3607 {
3608 if (sk->sk_socket && sk->sk_socket->file)
3609 if (send_sigurg(sk->sk_socket->file))
3610 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3611 }
3612 EXPORT_SYMBOL(sk_send_sigurg);
3613
sk_reset_timer(struct sock * sk,struct timer_list * timer,unsigned long expires)3614 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3615 unsigned long expires)
3616 {
3617 if (!mod_timer(timer, expires))
3618 sock_hold(sk);
3619 }
3620 EXPORT_SYMBOL(sk_reset_timer);
3621
sk_stop_timer(struct sock * sk,struct timer_list * timer)3622 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3623 {
3624 if (timer_delete(timer))
3625 __sock_put(sk);
3626 }
3627 EXPORT_SYMBOL(sk_stop_timer);
3628
sk_stop_timer_sync(struct sock * sk,struct timer_list * timer)3629 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3630 {
3631 if (timer_delete_sync(timer))
3632 __sock_put(sk);
3633 }
3634 EXPORT_SYMBOL(sk_stop_timer_sync);
3635
sock_init_data_uid(struct socket * sock,struct sock * sk,kuid_t uid)3636 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3637 {
3638 sk_init_common(sk);
3639 sk->sk_send_head = NULL;
3640
3641 timer_setup(&sk->sk_timer, NULL, 0);
3642
3643 sk->sk_allocation = GFP_KERNEL;
3644 sk->sk_rcvbuf = READ_ONCE(sysctl_rmem_default);
3645 sk->sk_sndbuf = READ_ONCE(sysctl_wmem_default);
3646 sk->sk_state = TCP_CLOSE;
3647 sk->sk_use_task_frag = true;
3648 sk_set_socket(sk, sock);
3649
3650 sock_set_flag(sk, SOCK_ZAPPED);
3651
3652 if (sock) {
3653 sk->sk_type = sock->type;
3654 RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3655 sock->sk = sk;
3656 } else {
3657 RCU_INIT_POINTER(sk->sk_wq, NULL);
3658 }
3659 sk->sk_uid = uid;
3660
3661 sk->sk_state_change = sock_def_wakeup;
3662 sk->sk_data_ready = sock_def_readable;
3663 sk->sk_write_space = sock_def_write_space;
3664 sk->sk_error_report = sock_def_error_report;
3665 sk->sk_destruct = sock_def_destruct;
3666
3667 sk->sk_frag.page = NULL;
3668 sk->sk_frag.offset = 0;
3669 sk->sk_peek_off = -1;
3670
3671 sk->sk_peer_pid = NULL;
3672 sk->sk_peer_cred = NULL;
3673 spin_lock_init(&sk->sk_peer_lock);
3674
3675 sk->sk_write_pending = 0;
3676 sk->sk_rcvlowat = 1;
3677 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
3678 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
3679
3680 sk->sk_stamp = SK_DEFAULT_STAMP;
3681 #if BITS_PER_LONG==32
3682 seqlock_init(&sk->sk_stamp_seq);
3683 #endif
3684 atomic_set(&sk->sk_zckey, 0);
3685
3686 #ifdef CONFIG_NET_RX_BUSY_POLL
3687 sk->sk_napi_id = 0;
3688 sk->sk_ll_usec = READ_ONCE(sysctl_net_busy_read);
3689 #endif
3690
3691 sk->sk_max_pacing_rate = ~0UL;
3692 sk->sk_pacing_rate = ~0UL;
3693 WRITE_ONCE(sk->sk_pacing_shift, 10);
3694 sk->sk_incoming_cpu = -1;
3695
3696 sk_rx_queue_clear(sk);
3697 /*
3698 * Before updating sk_refcnt, we must commit prior changes to memory
3699 * (Documentation/RCU/rculist_nulls.rst for details)
3700 */
3701 smp_wmb();
3702 refcount_set(&sk->sk_refcnt, 1);
3703 sk_drops_reset(sk);
3704 }
3705 EXPORT_SYMBOL(sock_init_data_uid);
3706
sock_init_data(struct socket * sock,struct sock * sk)3707 void sock_init_data(struct socket *sock, struct sock *sk)
3708 {
3709 kuid_t uid = sock ?
3710 SOCK_INODE(sock)->i_uid :
3711 make_kuid(sock_net(sk)->user_ns, 0);
3712
3713 sock_init_data_uid(sock, sk, uid);
3714 }
3715 EXPORT_SYMBOL(sock_init_data);
3716
lock_sock_nested(struct sock * sk,int subclass)3717 void lock_sock_nested(struct sock *sk, int subclass)
3718 {
3719 /* The sk_lock has mutex_lock() semantics here. */
3720 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3721
3722 might_sleep();
3723 spin_lock_bh(&sk->sk_lock.slock);
3724 if (sock_owned_by_user_nocheck(sk))
3725 __lock_sock(sk);
3726 sk->sk_lock.owned = 1;
3727 spin_unlock_bh(&sk->sk_lock.slock);
3728 }
3729 EXPORT_SYMBOL(lock_sock_nested);
3730
release_sock(struct sock * sk)3731 void release_sock(struct sock *sk)
3732 {
3733 spin_lock_bh(&sk->sk_lock.slock);
3734 if (sk->sk_backlog.tail)
3735 __release_sock(sk);
3736
3737 if (sk->sk_prot->release_cb)
3738 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3739 tcp_release_cb, sk);
3740
3741 sock_release_ownership(sk);
3742 if (waitqueue_active(&sk->sk_lock.wq))
3743 wake_up(&sk->sk_lock.wq);
3744 spin_unlock_bh(&sk->sk_lock.slock);
3745 }
3746 EXPORT_SYMBOL(release_sock);
3747
__lock_sock_fast(struct sock * sk)3748 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3749 {
3750 might_sleep();
3751 spin_lock_bh(&sk->sk_lock.slock);
3752
3753 if (!sock_owned_by_user_nocheck(sk)) {
3754 /*
3755 * Fast path return with bottom halves disabled and
3756 * sock::sk_lock.slock held.
3757 *
3758 * The 'mutex' is not contended and holding
3759 * sock::sk_lock.slock prevents all other lockers to
3760 * proceed so the corresponding unlock_sock_fast() can
3761 * avoid the slow path of release_sock() completely and
3762 * just release slock.
3763 *
3764 * From a semantical POV this is equivalent to 'acquiring'
3765 * the 'mutex', hence the corresponding lockdep
3766 * mutex_release() has to happen in the fast path of
3767 * unlock_sock_fast().
3768 */
3769 return false;
3770 }
3771
3772 __lock_sock(sk);
3773 sk->sk_lock.owned = 1;
3774 __acquire(&sk->sk_lock.slock);
3775 spin_unlock_bh(&sk->sk_lock.slock);
3776 return true;
3777 }
3778 EXPORT_SYMBOL(__lock_sock_fast);
3779
sock_gettstamp(struct socket * sock,void __user * userstamp,bool timeval,bool time32)3780 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3781 bool timeval, bool time32)
3782 {
3783 struct sock *sk = sock->sk;
3784 struct timespec64 ts;
3785
3786 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3787 ts = ktime_to_timespec64(sock_read_timestamp(sk));
3788 if (ts.tv_sec == -1)
3789 return -ENOENT;
3790 if (ts.tv_sec == 0) {
3791 ktime_t kt = ktime_get_real();
3792 sock_write_timestamp(sk, kt);
3793 ts = ktime_to_timespec64(kt);
3794 }
3795
3796 if (timeval)
3797 ts.tv_nsec /= 1000;
3798
3799 #ifdef CONFIG_COMPAT_32BIT_TIME
3800 if (time32)
3801 return put_old_timespec32(&ts, userstamp);
3802 #endif
3803 #ifdef CONFIG_SPARC64
3804 /* beware of padding in sparc64 timeval */
3805 if (timeval && !in_compat_syscall()) {
3806 struct __kernel_old_timeval __user tv = {
3807 .tv_sec = ts.tv_sec,
3808 .tv_usec = ts.tv_nsec,
3809 };
3810 if (copy_to_user(userstamp, &tv, sizeof(tv)))
3811 return -EFAULT;
3812 return 0;
3813 }
3814 #endif
3815 return put_timespec64(&ts, userstamp);
3816 }
3817 EXPORT_SYMBOL(sock_gettstamp);
3818
sock_enable_timestamp(struct sock * sk,enum sock_flags flag)3819 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3820 {
3821 if (!sock_flag(sk, flag)) {
3822 unsigned long previous_flags = sk->sk_flags;
3823
3824 sock_set_flag(sk, flag);
3825 /*
3826 * we just set one of the two flags which require net
3827 * time stamping, but time stamping might have been on
3828 * already because of the other one
3829 */
3830 if (sock_needs_netstamp(sk) &&
3831 !(previous_flags & SK_FLAGS_TIMESTAMP))
3832 net_enable_timestamp();
3833 }
3834 }
3835
sock_recv_errqueue(struct sock * sk,struct msghdr * msg,int len,int level,int type)3836 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3837 int level, int type)
3838 {
3839 struct sock_exterr_skb *serr;
3840 struct sk_buff *skb;
3841 int copied, err;
3842
3843 err = -EAGAIN;
3844 skb = sock_dequeue_err_skb(sk);
3845 if (skb == NULL)
3846 goto out;
3847
3848 copied = skb->len;
3849 if (copied > len) {
3850 msg->msg_flags |= MSG_TRUNC;
3851 copied = len;
3852 }
3853 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3854 if (err)
3855 goto out_free_skb;
3856
3857 sock_recv_timestamp(msg, sk, skb);
3858
3859 serr = SKB_EXT_ERR(skb);
3860 put_cmsg(msg, level, type, sizeof(serr->ee), &serr->ee);
3861
3862 msg->msg_flags |= MSG_ERRQUEUE;
3863 err = copied;
3864
3865 out_free_skb:
3866 kfree_skb(skb);
3867 out:
3868 return err;
3869 }
3870 EXPORT_SYMBOL(sock_recv_errqueue);
3871
3872 /*
3873 * Get a socket option on an socket.
3874 *
3875 * FIX: POSIX 1003.1g is very ambiguous here. It states that
3876 * asynchronous errors should be reported by getsockopt. We assume
3877 * this means if you specify SO_ERROR (otherwise what is the point of it).
3878 */
sock_common_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)3879 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3880 char __user *optval, int __user *optlen)
3881 {
3882 struct sock *sk = sock->sk;
3883
3884 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
3885 return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3886 }
3887 EXPORT_SYMBOL(sock_common_getsockopt);
3888
sock_common_recvmsg(struct socket * sock,struct msghdr * msg,size_t size,int flags)3889 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3890 int flags)
3891 {
3892 struct sock *sk = sock->sk;
3893 int addr_len = 0;
3894 int err;
3895
3896 err = sk->sk_prot->recvmsg(sk, msg, size, flags, &addr_len);
3897 if (err >= 0)
3898 msg->msg_namelen = addr_len;
3899 return err;
3900 }
3901 EXPORT_SYMBOL(sock_common_recvmsg);
3902
3903 /*
3904 * Set socket options on an inet socket.
3905 */
sock_common_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)3906 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3907 sockptr_t optval, unsigned int optlen)
3908 {
3909 struct sock *sk = sock->sk;
3910
3911 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
3912 return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3913 }
3914 EXPORT_SYMBOL(sock_common_setsockopt);
3915
sk_common_release(struct sock * sk)3916 void sk_common_release(struct sock *sk)
3917 {
3918 if (sk->sk_prot->destroy)
3919 sk->sk_prot->destroy(sk);
3920
3921 /*
3922 * Observation: when sk_common_release is called, processes have
3923 * no access to socket. But net still has.
3924 * Step one, detach it from networking:
3925 *
3926 * A. Remove from hash tables.
3927 */
3928
3929 sk->sk_prot->unhash(sk);
3930
3931 /*
3932 * In this point socket cannot receive new packets, but it is possible
3933 * that some packets are in flight because some CPU runs receiver and
3934 * did hash table lookup before we unhashed socket. They will achieve
3935 * receive queue and will be purged by socket destructor.
3936 *
3937 * Also we still have packets pending on receive queue and probably,
3938 * our own packets waiting in device queues. sock_destroy will drain
3939 * receive queue, but transmitted packets will delay socket destruction
3940 * until the last reference will be released.
3941 */
3942
3943 sock_orphan(sk);
3944
3945 xfrm_sk_free_policy(sk);
3946
3947 sock_put(sk);
3948 }
3949 EXPORT_SYMBOL(sk_common_release);
3950
sk_get_meminfo(const struct sock * sk,u32 * mem)3951 void sk_get_meminfo(const struct sock *sk, u32 *mem)
3952 {
3953 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
3954
3955 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
3956 mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
3957 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
3958 mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
3959 mem[SK_MEMINFO_FWD_ALLOC] = READ_ONCE(sk->sk_forward_alloc);
3960 mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
3961 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
3962 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
3963 mem[SK_MEMINFO_DROPS] = sk_drops_read(sk);
3964 }
3965
3966 #ifdef CONFIG_PROC_FS
3967 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
3968
sock_prot_inuse_get(struct net * net,struct proto * prot)3969 int sock_prot_inuse_get(struct net *net, struct proto *prot)
3970 {
3971 int cpu, idx = prot->inuse_idx;
3972 int res = 0;
3973
3974 for_each_possible_cpu(cpu)
3975 res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
3976
3977 return res >= 0 ? res : 0;
3978 }
3979 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
3980
sock_inuse_get(struct net * net)3981 int sock_inuse_get(struct net *net)
3982 {
3983 int cpu, res = 0;
3984
3985 for_each_possible_cpu(cpu)
3986 res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
3987
3988 return res;
3989 }
3990
3991 EXPORT_SYMBOL_GPL(sock_inuse_get);
3992
sock_inuse_init_net(struct net * net)3993 static int __net_init sock_inuse_init_net(struct net *net)
3994 {
3995 net->core.prot_inuse = alloc_percpu(struct prot_inuse);
3996 if (net->core.prot_inuse == NULL)
3997 return -ENOMEM;
3998 return 0;
3999 }
4000
sock_inuse_exit_net(struct net * net)4001 static void __net_exit sock_inuse_exit_net(struct net *net)
4002 {
4003 free_percpu(net->core.prot_inuse);
4004 }
4005
4006 static struct pernet_operations net_inuse_ops = {
4007 .init = sock_inuse_init_net,
4008 .exit = sock_inuse_exit_net,
4009 };
4010
net_inuse_init(void)4011 static __init int net_inuse_init(void)
4012 {
4013 if (register_pernet_subsys(&net_inuse_ops))
4014 panic("Cannot initialize net inuse counters");
4015
4016 return 0;
4017 }
4018
4019 core_initcall(net_inuse_init);
4020
assign_proto_idx(struct proto * prot)4021 static int assign_proto_idx(struct proto *prot)
4022 {
4023 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
4024
4025 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR)) {
4026 pr_err("PROTO_INUSE_NR exhausted\n");
4027 return -ENOSPC;
4028 }
4029
4030 set_bit(prot->inuse_idx, proto_inuse_idx);
4031 return 0;
4032 }
4033
release_proto_idx(struct proto * prot)4034 static void release_proto_idx(struct proto *prot)
4035 {
4036 if (prot->inuse_idx != PROTO_INUSE_NR)
4037 clear_bit(prot->inuse_idx, proto_inuse_idx);
4038 }
4039 #else
assign_proto_idx(struct proto * prot)4040 static inline int assign_proto_idx(struct proto *prot)
4041 {
4042 return 0;
4043 }
4044
release_proto_idx(struct proto * prot)4045 static inline void release_proto_idx(struct proto *prot)
4046 {
4047 }
4048
4049 #endif
4050
tw_prot_cleanup(struct timewait_sock_ops * twsk_prot)4051 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
4052 {
4053 if (!twsk_prot)
4054 return;
4055 kfree(twsk_prot->twsk_slab_name);
4056 twsk_prot->twsk_slab_name = NULL;
4057 kmem_cache_destroy(twsk_prot->twsk_slab);
4058 twsk_prot->twsk_slab = NULL;
4059 }
4060
tw_prot_init(const struct proto * prot)4061 static int tw_prot_init(const struct proto *prot)
4062 {
4063 struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
4064
4065 if (!twsk_prot)
4066 return 0;
4067
4068 twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
4069 prot->name);
4070 if (!twsk_prot->twsk_slab_name)
4071 return -ENOMEM;
4072
4073 twsk_prot->twsk_slab =
4074 kmem_cache_create(twsk_prot->twsk_slab_name,
4075 twsk_prot->twsk_obj_size, 0,
4076 SLAB_ACCOUNT | prot->slab_flags,
4077 NULL);
4078 if (!twsk_prot->twsk_slab) {
4079 pr_crit("%s: Can't create timewait sock SLAB cache!\n",
4080 prot->name);
4081 return -ENOMEM;
4082 }
4083
4084 return 0;
4085 }
4086
req_prot_cleanup(struct request_sock_ops * rsk_prot)4087 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
4088 {
4089 if (!rsk_prot)
4090 return;
4091 kfree(rsk_prot->slab_name);
4092 rsk_prot->slab_name = NULL;
4093 kmem_cache_destroy(rsk_prot->slab);
4094 rsk_prot->slab = NULL;
4095 }
4096
req_prot_init(const struct proto * prot)4097 static int req_prot_init(const struct proto *prot)
4098 {
4099 struct request_sock_ops *rsk_prot = prot->rsk_prot;
4100
4101 if (!rsk_prot)
4102 return 0;
4103
4104 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
4105 prot->name);
4106 if (!rsk_prot->slab_name)
4107 return -ENOMEM;
4108
4109 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
4110 rsk_prot->obj_size, 0,
4111 SLAB_ACCOUNT | prot->slab_flags,
4112 NULL);
4113
4114 if (!rsk_prot->slab) {
4115 pr_crit("%s: Can't create request sock SLAB cache!\n",
4116 prot->name);
4117 return -ENOMEM;
4118 }
4119 return 0;
4120 }
4121
proto_register(struct proto * prot,int alloc_slab)4122 int proto_register(struct proto *prot, int alloc_slab)
4123 {
4124 int ret = -ENOBUFS;
4125
4126 if (prot->memory_allocated && !prot->sysctl_mem) {
4127 pr_err("%s: missing sysctl_mem\n", prot->name);
4128 return -EINVAL;
4129 }
4130 if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
4131 pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
4132 return -EINVAL;
4133 }
4134 if (alloc_slab) {
4135 prot->slab = kmem_cache_create_usercopy(prot->name,
4136 prot->obj_size, 0,
4137 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
4138 prot->slab_flags,
4139 prot->useroffset, prot->usersize,
4140 NULL);
4141
4142 if (prot->slab == NULL) {
4143 pr_crit("%s: Can't create sock SLAB cache!\n",
4144 prot->name);
4145 goto out;
4146 }
4147
4148 if (req_prot_init(prot))
4149 goto out_free_request_sock_slab;
4150
4151 if (tw_prot_init(prot))
4152 goto out_free_timewait_sock_slab;
4153 }
4154
4155 mutex_lock(&proto_list_mutex);
4156 ret = assign_proto_idx(prot);
4157 if (ret) {
4158 mutex_unlock(&proto_list_mutex);
4159 goto out_free_timewait_sock_slab;
4160 }
4161 list_add(&prot->node, &proto_list);
4162 mutex_unlock(&proto_list_mutex);
4163 return ret;
4164
4165 out_free_timewait_sock_slab:
4166 if (alloc_slab)
4167 tw_prot_cleanup(prot->twsk_prot);
4168 out_free_request_sock_slab:
4169 if (alloc_slab) {
4170 req_prot_cleanup(prot->rsk_prot);
4171
4172 kmem_cache_destroy(prot->slab);
4173 prot->slab = NULL;
4174 }
4175 out:
4176 return ret;
4177 }
4178 EXPORT_SYMBOL(proto_register);
4179
proto_unregister(struct proto * prot)4180 void proto_unregister(struct proto *prot)
4181 {
4182 mutex_lock(&proto_list_mutex);
4183 release_proto_idx(prot);
4184 list_del(&prot->node);
4185 mutex_unlock(&proto_list_mutex);
4186
4187 kmem_cache_destroy(prot->slab);
4188 prot->slab = NULL;
4189
4190 req_prot_cleanup(prot->rsk_prot);
4191 tw_prot_cleanup(prot->twsk_prot);
4192 }
4193 EXPORT_SYMBOL(proto_unregister);
4194
sock_load_diag_module(int family,int protocol)4195 int sock_load_diag_module(int family, int protocol)
4196 {
4197 if (!protocol) {
4198 if (!sock_is_registered(family))
4199 return -ENOENT;
4200
4201 return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4202 NETLINK_SOCK_DIAG, family);
4203 }
4204
4205 #ifdef CONFIG_INET
4206 if (family == AF_INET &&
4207 protocol != IPPROTO_RAW &&
4208 protocol < MAX_INET_PROTOS &&
4209 !rcu_access_pointer(inet_protos[protocol]))
4210 return -ENOENT;
4211 #endif
4212
4213 return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4214 NETLINK_SOCK_DIAG, family, protocol);
4215 }
4216 EXPORT_SYMBOL(sock_load_diag_module);
4217
4218 #ifdef CONFIG_PROC_FS
proto_seq_start(struct seq_file * seq,loff_t * pos)4219 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4220 __acquires(proto_list_mutex)
4221 {
4222 mutex_lock(&proto_list_mutex);
4223 return seq_list_start_head(&proto_list, *pos);
4224 }
4225
proto_seq_next(struct seq_file * seq,void * v,loff_t * pos)4226 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4227 {
4228 return seq_list_next(v, &proto_list, pos);
4229 }
4230
proto_seq_stop(struct seq_file * seq,void * v)4231 static void proto_seq_stop(struct seq_file *seq, void *v)
4232 __releases(proto_list_mutex)
4233 {
4234 mutex_unlock(&proto_list_mutex);
4235 }
4236
proto_method_implemented(const void * method)4237 static char proto_method_implemented(const void *method)
4238 {
4239 return method == NULL ? 'n' : 'y';
4240 }
sock_prot_memory_allocated(struct proto * proto)4241 static long sock_prot_memory_allocated(struct proto *proto)
4242 {
4243 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4244 }
4245
sock_prot_memory_pressure(struct proto * proto)4246 static const char *sock_prot_memory_pressure(struct proto *proto)
4247 {
4248 return proto->memory_pressure != NULL ?
4249 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4250 }
4251
proto_seq_printf(struct seq_file * seq,struct proto * proto)4252 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4253 {
4254
4255 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
4256 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4257 proto->name,
4258 proto->obj_size,
4259 sock_prot_inuse_get(seq_file_net(seq), proto),
4260 sock_prot_memory_allocated(proto),
4261 sock_prot_memory_pressure(proto),
4262 proto->max_header,
4263 proto->slab == NULL ? "no" : "yes",
4264 module_name(proto->owner),
4265 proto_method_implemented(proto->close),
4266 proto_method_implemented(proto->connect),
4267 proto_method_implemented(proto->disconnect),
4268 proto_method_implemented(proto->accept),
4269 proto_method_implemented(proto->ioctl),
4270 proto_method_implemented(proto->init),
4271 proto_method_implemented(proto->destroy),
4272 proto_method_implemented(proto->shutdown),
4273 proto_method_implemented(proto->setsockopt),
4274 proto_method_implemented(proto->getsockopt),
4275 proto_method_implemented(proto->sendmsg),
4276 proto_method_implemented(proto->recvmsg),
4277 proto_method_implemented(proto->bind),
4278 proto_method_implemented(proto->backlog_rcv),
4279 proto_method_implemented(proto->hash),
4280 proto_method_implemented(proto->unhash),
4281 proto_method_implemented(proto->get_port),
4282 proto_method_implemented(proto->enter_memory_pressure));
4283 }
4284
proto_seq_show(struct seq_file * seq,void * v)4285 static int proto_seq_show(struct seq_file *seq, void *v)
4286 {
4287 if (v == &proto_list)
4288 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4289 "protocol",
4290 "size",
4291 "sockets",
4292 "memory",
4293 "press",
4294 "maxhdr",
4295 "slab",
4296 "module",
4297 "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4298 else
4299 proto_seq_printf(seq, list_entry(v, struct proto, node));
4300 return 0;
4301 }
4302
4303 static const struct seq_operations proto_seq_ops = {
4304 .start = proto_seq_start,
4305 .next = proto_seq_next,
4306 .stop = proto_seq_stop,
4307 .show = proto_seq_show,
4308 };
4309
proto_init_net(struct net * net)4310 static __net_init int proto_init_net(struct net *net)
4311 {
4312 if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4313 sizeof(struct seq_net_private)))
4314 return -ENOMEM;
4315
4316 return 0;
4317 }
4318
proto_exit_net(struct net * net)4319 static __net_exit void proto_exit_net(struct net *net)
4320 {
4321 remove_proc_entry("protocols", net->proc_net);
4322 }
4323
4324
4325 static __net_initdata struct pernet_operations proto_net_ops = {
4326 .init = proto_init_net,
4327 .exit = proto_exit_net,
4328 };
4329
proto_init(void)4330 static int __init proto_init(void)
4331 {
4332 return register_pernet_subsys(&proto_net_ops);
4333 }
4334
4335 subsys_initcall(proto_init);
4336
4337 #endif /* PROC_FS */
4338
4339 #ifdef CONFIG_NET_RX_BUSY_POLL
sk_busy_loop_end(void * p,unsigned long start_time)4340 bool sk_busy_loop_end(void *p, unsigned long start_time)
4341 {
4342 struct sock *sk = p;
4343
4344 if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4345 return true;
4346
4347 if (sk_is_udp(sk) &&
4348 !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4349 return true;
4350
4351 return sk_busy_loop_timeout(sk, start_time);
4352 }
4353 EXPORT_SYMBOL(sk_busy_loop_end);
4354 #endif /* CONFIG_NET_RX_BUSY_POLL */
4355
sock_bind_add(struct sock * sk,struct sockaddr * addr,int addr_len)4356 int sock_bind_add(struct sock *sk, struct sockaddr *addr, int addr_len)
4357 {
4358 if (!sk->sk_prot->bind_add)
4359 return -EOPNOTSUPP;
4360 return sk->sk_prot->bind_add(sk, addr, addr_len);
4361 }
4362 EXPORT_SYMBOL(sock_bind_add);
4363
4364 /* Copy 'size' bytes from userspace and return `size` back to userspace */
sock_ioctl_inout(struct sock * sk,unsigned int cmd,void __user * arg,void * karg,size_t size)4365 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4366 void __user *arg, void *karg, size_t size)
4367 {
4368 int ret;
4369
4370 if (copy_from_user(karg, arg, size))
4371 return -EFAULT;
4372
4373 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4374 if (ret)
4375 return ret;
4376
4377 if (copy_to_user(arg, karg, size))
4378 return -EFAULT;
4379
4380 return 0;
4381 }
4382 EXPORT_SYMBOL(sock_ioctl_inout);
4383
4384 /* This is the most common ioctl prep function, where the result (4 bytes) is
4385 * copied back to userspace if the ioctl() returns successfully. No input is
4386 * copied from userspace as input argument.
4387 */
sock_ioctl_out(struct sock * sk,unsigned int cmd,void __user * arg)4388 static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4389 {
4390 int ret, karg = 0;
4391
4392 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4393 if (ret)
4394 return ret;
4395
4396 return put_user(karg, (int __user *)arg);
4397 }
4398
4399 /* A wrapper around sock ioctls, which copies the data from userspace
4400 * (depending on the protocol/ioctl), and copies back the result to userspace.
4401 * The main motivation for this function is to pass kernel memory to the
4402 * protocol ioctl callbacks, instead of userspace memory.
4403 */
sk_ioctl(struct sock * sk,unsigned int cmd,void __user * arg)4404 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4405 {
4406 int rc = 1;
4407
4408 if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4409 rc = ipmr_sk_ioctl(sk, cmd, arg);
4410 else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4411 rc = ip6mr_sk_ioctl(sk, cmd, arg);
4412 else if (sk_is_phonet(sk))
4413 rc = phonet_sk_ioctl(sk, cmd, arg);
4414
4415 /* If ioctl was processed, returns its value */
4416 if (rc <= 0)
4417 return rc;
4418
4419 /* Otherwise call the default handler */
4420 return sock_ioctl_out(sk, cmd, arg);
4421 }
4422 EXPORT_SYMBOL(sk_ioctl);
4423
sock_struct_check(void)4424 static int __init sock_struct_check(void)
4425 {
4426 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_drops);
4427 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_peek_off);
4428 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_error_queue);
4429 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_receive_queue);
4430 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_backlog);
4431
4432 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst);
4433 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_ifindex);
4434 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_cookie);
4435 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvbuf);
4436 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_filter);
4437 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_wq);
4438 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_data_ready);
4439 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvtimeo);
4440 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvlowat);
4441
4442 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_err);
4443 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_socket);
4444 #ifdef CONFIG_MEMCG
4445 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_memcg);
4446 #endif
4447
4448 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_lock);
4449 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_reserved_mem);
4450 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_forward_alloc);
4451 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_tsflags);
4452
4453 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4454 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4455 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_err_soft);
4456 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_queued);
4457 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_alloc);
4458 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tsq_flags);
4459 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_send_head);
4460 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_queue);
4461 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_pending);
4462 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_dst_pending_confirm);
4463 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_status);
4464 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_frag);
4465 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_timer);
4466 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_rate);
4467 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_zckey);
4468 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tskey);
4469
4470 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_max_pacing_rate);
4471 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndtimeo);
4472 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_priority);
4473 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_mark);
4474 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_uid);
4475 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_protocol);
4476 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_cache);
4477 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_route_caps);
4478 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_type);
4479 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_size);
4480 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_allocation);
4481 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_txhash);
4482 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndbuf);
4483 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_segs);
4484 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_shift);
4485 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_use_task_frag);
4486 return 0;
4487 }
4488
4489 core_initcall(sock_struct_check);
4490