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