1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * Generic socket support routines. Memory allocators, socket lock/release
8 * handler for protocols to use and generic option handler.
9 *
10 * Authors: Ross Biro
11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12 * Florian La Roche, <flla@stud.uni-sb.de>
13 * Alan Cox, <A.Cox@swansea.ac.uk>
14 *
15 * Fixes:
16 * Alan Cox : Numerous verify_area() problems
17 * Alan Cox : Connecting on a connecting socket
18 * now returns an error for tcp.
19 * Alan Cox : sock->protocol is set correctly.
20 * and is not sometimes left as 0.
21 * Alan Cox : connect handles icmp errors on a
22 * connect properly. Unfortunately there
23 * is a restart syscall nasty there. I
24 * can't match BSD without hacking the C
25 * library. Ideas urgently sought!
26 * Alan Cox : Disallow bind() to addresses that are
27 * not ours - especially broadcast ones!!
28 * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost)
29 * Alan Cox : sock_wfree/sock_rfree don't destroy sockets,
30 * instead they leave that for the DESTROY timer.
31 * Alan Cox : Clean up error flag in accept
32 * Alan Cox : TCP ack handling is buggy, the DESTROY timer
33 * was buggy. Put a remove_sock() in the handler
34 * for memory when we hit 0. Also altered the timer
35 * code. The ACK stuff can wait and needs major
36 * TCP layer surgery.
37 * Alan Cox : Fixed TCP ack bug, removed remove sock
38 * and fixed timer/inet_bh race.
39 * Alan Cox : Added zapped flag for TCP
40 * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code
41 * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb
42 * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources
43 * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing.
44 * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so...
45 * Rick Sladkey : Relaxed UDP rules for matching packets.
46 * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support
47 * Pauline Middelink : identd support
48 * Alan Cox : Fixed connect() taking signals I think.
49 * Alan Cox : SO_LINGER supported
50 * Alan Cox : Error reporting fixes
51 * Anonymous : inet_create tidied up (sk->reuse setting)
52 * Alan Cox : inet sockets don't set sk->type!
53 * Alan Cox : Split socket option code
54 * Alan Cox : Callbacks
55 * Alan Cox : Nagle flag for Charles & Johannes stuff
56 * Alex : Removed restriction on inet fioctl
57 * Alan Cox : Splitting INET from NET core
58 * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt()
59 * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code
60 * Alan Cox : Split IP from generic code
61 * Alan Cox : New kfree_skbmem()
62 * Alan Cox : Make SO_DEBUG superuser only.
63 * Alan Cox : Allow anyone to clear SO_DEBUG
64 * (compatibility fix)
65 * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput.
66 * Alan Cox : Allocator for a socket is settable.
67 * Alan Cox : SO_ERROR includes soft errors.
68 * Alan Cox : Allow NULL arguments on some SO_ opts
69 * Alan Cox : Generic socket allocation to make hooks
70 * easier (suggested by Craig Metz).
71 * Michael Pall : SO_ERROR returns positive errno again
72 * Steve Whitehouse: Added default destructor to free
73 * protocol private data.
74 * Steve Whitehouse: Added various other default routines
75 * common to several socket families.
76 * Chris Evans : Call suser() check last on F_SETOWN
77 * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER.
78 * Andi Kleen : Add sock_kmalloc()/sock_kfree_s()
79 * Andi Kleen : Fix write_space callback
80 * Chris Evans : Security fixes - signedness again
81 * Arnaldo C. Melo : cleanups, use skb_queue_purge
82 *
83 * To Fix:
84 */
85
86 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
87
88 #include <linux/unaligned.h>
89 #include <linux/capability.h>
90 #include <linux/errno.h>
91 #include <linux/errqueue.h>
92 #include <linux/types.h>
93 #include <linux/socket.h>
94 #include <linux/in.h>
95 #include <linux/kernel.h>
96 #include <linux/module.h>
97 #include <linux/proc_fs.h>
98 #include <linux/seq_file.h>
99 #include <linux/sched.h>
100 #include <linux/sched/mm.h>
101 #include <linux/timer.h>
102 #include <linux/string.h>
103 #include <linux/sockios.h>
104 #include <linux/net.h>
105 #include <linux/mm.h>
106 #include <linux/slab.h>
107 #include <linux/interrupt.h>
108 #include <linux/poll.h>
109 #include <linux/tcp.h>
110 #include <linux/udp.h>
111 #include <linux/init.h>
112 #include <linux/highmem.h>
113 #include <linux/user_namespace.h>
114 #include <linux/static_key.h>
115 #include <linux/memcontrol.h>
116 #include <linux/prefetch.h>
117 #include <linux/compat.h>
118 #include <linux/mroute.h>
119 #include <linux/mroute6.h>
120 #include <linux/icmpv6.h>
121
122 #include <linux/uaccess.h>
123
124 #include <linux/netdevice.h>
125 #include <net/protocol.h>
126 #include <linux/skbuff.h>
127 #include <linux/skbuff_ref.h>
128 #include <net/net_namespace.h>
129 #include <net/request_sock.h>
130 #include <net/sock.h>
131 #include <net/proto_memory.h>
132 #include <linux/net_tstamp.h>
133 #include <net/xfrm.h>
134 #include <linux/ipsec.h>
135 #include <net/cls_cgroup.h>
136 #include <net/netprio_cgroup.h>
137 #include <linux/sock_diag.h>
138
139 #include <linux/filter.h>
140 #include <net/sock_reuseport.h>
141 #include <net/bpf_sk_storage.h>
142
143 #include <trace/events/sock.h>
144
145 #include <net/tcp.h>
146 #include <net/busy_poll.h>
147 #include <net/phonet/phonet.h>
148
149 #include <linux/ethtool.h>
150
151 #include <uapi/linux/pidfd.h>
152
153 #include "dev.h"
154
155 static DEFINE_MUTEX(proto_list_mutex);
156 static LIST_HEAD(proto_list);
157
158 static void sock_def_write_space_wfree(struct sock *sk, int wmem_alloc);
159 static void sock_def_write_space(struct sock *sk);
160
161 /**
162 * sk_ns_capable - General socket capability test
163 * @sk: Socket to use a capability on or through
164 * @user_ns: The user namespace of the capability to use
165 * @cap: The capability to use
166 *
167 * Test to see if the opener of the socket had when the socket was
168 * created and the current process has the capability @cap in the user
169 * namespace @user_ns.
170 */
sk_ns_capable(const struct sock * sk,struct user_namespace * user_ns,int cap)171 bool sk_ns_capable(const struct sock *sk,
172 struct user_namespace *user_ns, int cap)
173 {
174 return file_ns_capable(sk->sk_socket->file, user_ns, cap) &&
175 ns_capable(user_ns, cap);
176 }
177 EXPORT_SYMBOL(sk_ns_capable);
178
179 /**
180 * sk_capable - Socket global capability test
181 * @sk: Socket to use a capability on or through
182 * @cap: The global capability to use
183 *
184 * Test to see if the opener of the socket had when the socket was
185 * created and the current process has the capability @cap in all user
186 * namespaces.
187 */
sk_capable(const struct sock * sk,int cap)188 bool sk_capable(const struct sock *sk, int cap)
189 {
190 return sk_ns_capable(sk, &init_user_ns, cap);
191 }
192 EXPORT_SYMBOL(sk_capable);
193
194 /**
195 * sk_net_capable - Network namespace socket capability test
196 * @sk: Socket to use a capability on or through
197 * @cap: The capability to use
198 *
199 * Test to see if the opener of the socket had when the socket was created
200 * and the current process has the capability @cap over the network namespace
201 * the socket is a member of.
202 */
sk_net_capable(const struct sock * sk,int cap)203 bool sk_net_capable(const struct sock *sk, int cap)
204 {
205 return sk_ns_capable(sk, sock_net(sk)->user_ns, cap);
206 }
207 EXPORT_SYMBOL(sk_net_capable);
208
209 /*
210 * Each address family might have different locking rules, so we have
211 * one slock key per address family and separate keys for internal and
212 * userspace sockets.
213 */
214 static struct lock_class_key af_family_keys[AF_MAX];
215 static struct lock_class_key af_family_kern_keys[AF_MAX];
216 static struct lock_class_key af_family_slock_keys[AF_MAX];
217 static struct lock_class_key af_family_kern_slock_keys[AF_MAX];
218
219 /*
220 * Make lock validator output more readable. (we pre-construct these
221 * strings build-time, so that runtime initialization of socket
222 * locks is fast):
223 */
224
225 #define _sock_locks(x) \
226 x "AF_UNSPEC", x "AF_UNIX" , x "AF_INET" , \
227 x "AF_AX25" , x "AF_IPX" , x "AF_APPLETALK", \
228 x "AF_NETROM", x "AF_BRIDGE" , x "AF_ATMPVC" , \
229 x "AF_X25" , x "AF_INET6" , x "AF_ROSE" , \
230 x "AF_DECnet", x "AF_NETBEUI" , x "AF_SECURITY" , \
231 x "AF_KEY" , x "AF_NETLINK" , x "AF_PACKET" , \
232 x "AF_ASH" , x "AF_ECONET" , x "AF_ATMSVC" , \
233 x "AF_RDS" , x "AF_SNA" , x "AF_IRDA" , \
234 x "AF_PPPOX" , x "AF_WANPIPE" , x "AF_LLC" , \
235 x "27" , x "28" , x "AF_CAN" , \
236 x "AF_TIPC" , x "AF_BLUETOOTH", x "IUCV" , \
237 x "AF_RXRPC" , x "AF_ISDN" , x "AF_PHONET" , \
238 x "AF_IEEE802154", x "AF_CAIF" , x "AF_ALG" , \
239 x "AF_NFC" , x "AF_VSOCK" , x "AF_KCM" , \
240 x "AF_QIPCRTR", x "AF_SMC" , x "AF_XDP" , \
241 x "AF_MCTP" , \
242 x "AF_MAX"
243
244 static const char *const af_family_key_strings[AF_MAX+1] = {
245 _sock_locks("sk_lock-")
246 };
247 static const char *const af_family_slock_key_strings[AF_MAX+1] = {
248 _sock_locks("slock-")
249 };
250 static const char *const af_family_clock_key_strings[AF_MAX+1] = {
251 _sock_locks("clock-")
252 };
253
254 static const char *const af_family_kern_key_strings[AF_MAX+1] = {
255 _sock_locks("k-sk_lock-")
256 };
257 static const char *const af_family_kern_slock_key_strings[AF_MAX+1] = {
258 _sock_locks("k-slock-")
259 };
260 static const char *const af_family_kern_clock_key_strings[AF_MAX+1] = {
261 _sock_locks("k-clock-")
262 };
263 static const char *const af_family_rlock_key_strings[AF_MAX+1] = {
264 _sock_locks("rlock-")
265 };
266 static const char *const af_family_wlock_key_strings[AF_MAX+1] = {
267 _sock_locks("wlock-")
268 };
269 static const char *const af_family_elock_key_strings[AF_MAX+1] = {
270 _sock_locks("elock-")
271 };
272
273 /*
274 * sk_callback_lock and sk queues locking rules are per-address-family,
275 * so split the lock classes by using a per-AF key:
276 */
277 static struct lock_class_key af_callback_keys[AF_MAX];
278 static struct lock_class_key af_rlock_keys[AF_MAX];
279 static struct lock_class_key af_wlock_keys[AF_MAX];
280 static struct lock_class_key af_elock_keys[AF_MAX];
281 static struct lock_class_key af_kern_callback_keys[AF_MAX];
282
283 /* Run time adjustable parameters. */
284 __u32 sysctl_wmem_max __read_mostly = 4 << 20;
285 EXPORT_SYMBOL(sysctl_wmem_max);
286 __u32 sysctl_rmem_max __read_mostly = 4 << 20;
287 EXPORT_SYMBOL(sysctl_rmem_max);
288 __u32 sysctl_wmem_default __read_mostly = SK_WMEM_DEFAULT;
289 __u32 sysctl_rmem_default __read_mostly = SK_RMEM_DEFAULT;
290
291 DEFINE_STATIC_KEY_FALSE(memalloc_socks_key);
292 EXPORT_SYMBOL_GPL(memalloc_socks_key);
293
294 /**
295 * sk_set_memalloc - sets %SOCK_MEMALLOC
296 * @sk: socket to set it on
297 *
298 * Set %SOCK_MEMALLOC on a socket for access to emergency reserves.
299 * It's the responsibility of the admin to adjust min_free_kbytes
300 * to meet the requirements
301 */
sk_set_memalloc(struct sock * sk)302 void sk_set_memalloc(struct sock *sk)
303 {
304 sock_set_flag(sk, SOCK_MEMALLOC);
305 sk->sk_allocation |= __GFP_MEMALLOC;
306 static_branch_inc(&memalloc_socks_key);
307 }
308 EXPORT_SYMBOL_GPL(sk_set_memalloc);
309
sk_clear_memalloc(struct sock * sk)310 void sk_clear_memalloc(struct sock *sk)
311 {
312 sock_reset_flag(sk, SOCK_MEMALLOC);
313 sk->sk_allocation &= ~__GFP_MEMALLOC;
314 static_branch_dec(&memalloc_socks_key);
315
316 /*
317 * SOCK_MEMALLOC is allowed to ignore rmem limits to ensure forward
318 * progress of swapping. SOCK_MEMALLOC may be cleared while
319 * it has rmem allocations due to the last swapfile being deactivated
320 * but there is a risk that the socket is unusable due to exceeding
321 * the rmem limits. Reclaim the reserves and obey rmem limits again.
322 */
323 sk_mem_reclaim(sk);
324 }
325 EXPORT_SYMBOL_GPL(sk_clear_memalloc);
326
__sk_backlog_rcv(struct sock * sk,struct sk_buff * skb)327 int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
328 {
329 int ret;
330 unsigned int noreclaim_flag;
331
332 /* these should have been dropped before queueing */
333 BUG_ON(!sock_flag(sk, SOCK_MEMALLOC));
334
335 noreclaim_flag = memalloc_noreclaim_save();
336 ret = INDIRECT_CALL_INET(sk->sk_backlog_rcv,
337 tcp_v6_do_rcv,
338 tcp_v4_do_rcv,
339 sk, skb);
340 memalloc_noreclaim_restore(noreclaim_flag);
341
342 return ret;
343 }
344 EXPORT_SYMBOL(__sk_backlog_rcv);
345
sk_error_report(struct sock * sk)346 void sk_error_report(struct sock *sk)
347 {
348 sk->sk_error_report(sk);
349
350 switch (sk->sk_family) {
351 case AF_INET:
352 fallthrough;
353 case AF_INET6:
354 trace_inet_sk_error_report(sk);
355 break;
356 default:
357 break;
358 }
359 }
360 EXPORT_SYMBOL(sk_error_report);
361
sock_get_timeout(long timeo,void * optval,bool old_timeval)362 int sock_get_timeout(long timeo, void *optval, bool old_timeval)
363 {
364 struct __kernel_sock_timeval tv;
365
366 if (timeo == MAX_SCHEDULE_TIMEOUT) {
367 tv.tv_sec = 0;
368 tv.tv_usec = 0;
369 } else {
370 tv.tv_sec = timeo / HZ;
371 tv.tv_usec = ((timeo % HZ) * USEC_PER_SEC) / HZ;
372 }
373
374 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
375 struct old_timeval32 tv32 = { tv.tv_sec, tv.tv_usec };
376 *(struct old_timeval32 *)optval = tv32;
377 return sizeof(tv32);
378 }
379
380 if (old_timeval) {
381 struct __kernel_old_timeval old_tv;
382 old_tv.tv_sec = tv.tv_sec;
383 old_tv.tv_usec = tv.tv_usec;
384 *(struct __kernel_old_timeval *)optval = old_tv;
385 return sizeof(old_tv);
386 }
387
388 *(struct __kernel_sock_timeval *)optval = tv;
389 return sizeof(tv);
390 }
391 EXPORT_SYMBOL(sock_get_timeout);
392
sock_copy_user_timeval(struct __kernel_sock_timeval * tv,sockptr_t optval,int optlen,bool old_timeval)393 int sock_copy_user_timeval(struct __kernel_sock_timeval *tv,
394 sockptr_t optval, int optlen, bool old_timeval)
395 {
396 if (old_timeval && in_compat_syscall() && !COMPAT_USE_64BIT_TIME) {
397 struct old_timeval32 tv32;
398
399 if (optlen < sizeof(tv32))
400 return -EINVAL;
401
402 if (copy_from_sockptr(&tv32, optval, sizeof(tv32)))
403 return -EFAULT;
404 tv->tv_sec = tv32.tv_sec;
405 tv->tv_usec = tv32.tv_usec;
406 } else if (old_timeval) {
407 struct __kernel_old_timeval old_tv;
408
409 if (optlen < sizeof(old_tv))
410 return -EINVAL;
411 if (copy_from_sockptr(&old_tv, optval, sizeof(old_tv)))
412 return -EFAULT;
413 tv->tv_sec = old_tv.tv_sec;
414 tv->tv_usec = old_tv.tv_usec;
415 } else {
416 if (optlen < sizeof(*tv))
417 return -EINVAL;
418 if (copy_from_sockptr(tv, optval, sizeof(*tv)))
419 return -EFAULT;
420 }
421
422 return 0;
423 }
424 EXPORT_SYMBOL(sock_copy_user_timeval);
425
sock_set_timeout(long * timeo_p,sockptr_t optval,int optlen,bool old_timeval)426 static int sock_set_timeout(long *timeo_p, sockptr_t optval, int optlen,
427 bool old_timeval)
428 {
429 struct __kernel_sock_timeval tv;
430 int err = sock_copy_user_timeval(&tv, optval, optlen, old_timeval);
431 long val;
432
433 if (err)
434 return err;
435
436 if (tv.tv_usec < 0 || tv.tv_usec >= USEC_PER_SEC)
437 return -EDOM;
438
439 if (tv.tv_sec < 0) {
440 static int warned __read_mostly;
441
442 WRITE_ONCE(*timeo_p, 0);
443 if (warned < 10 && net_ratelimit()) {
444 warned++;
445 pr_info("%s: `%s' (pid %d) tries to set negative timeout\n",
446 __func__, current->comm, task_pid_nr(current));
447 }
448 return 0;
449 }
450 val = MAX_SCHEDULE_TIMEOUT;
451 if ((tv.tv_sec || tv.tv_usec) &&
452 (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT / HZ - 1)))
453 val = tv.tv_sec * HZ + DIV_ROUND_UP((unsigned long)tv.tv_usec,
454 USEC_PER_SEC / HZ);
455 WRITE_ONCE(*timeo_p, val);
456 return 0;
457 }
458
sk_set_prio_allowed(const struct sock * sk,int val)459 static bool sk_set_prio_allowed(const struct sock *sk, int val)
460 {
461 return ((val >= TC_PRIO_BESTEFFORT && val <= TC_PRIO_INTERACTIVE) ||
462 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) ||
463 sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN));
464 }
465
sock_needs_netstamp(const struct sock * sk)466 static bool sock_needs_netstamp(const struct sock *sk)
467 {
468 switch (sk->sk_family) {
469 case AF_UNSPEC:
470 case AF_UNIX:
471 return false;
472 default:
473 return true;
474 }
475 }
476
sock_disable_timestamp(struct sock * sk,unsigned long flags)477 static void sock_disable_timestamp(struct sock *sk, unsigned long flags)
478 {
479 if (sk->sk_flags & flags) {
480 sk->sk_flags &= ~flags;
481 if (sock_needs_netstamp(sk) &&
482 !(sk->sk_flags & SK_FLAGS_TIMESTAMP))
483 net_disable_timestamp();
484 }
485 }
486
487
__sock_queue_rcv_skb(struct sock * sk,struct sk_buff * skb)488 int __sock_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
489 {
490 unsigned long flags;
491 struct sk_buff_head *list = &sk->sk_receive_queue;
492
493 if (atomic_read(&sk->sk_rmem_alloc) >= READ_ONCE(sk->sk_rcvbuf)) {
494 sk_drops_inc(sk);
495 trace_sock_rcvqueue_full(sk, skb);
496 return -ENOMEM;
497 }
498
499 if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
500 sk_drops_inc(sk);
501 return -ENOBUFS;
502 }
503
504 skb->dev = NULL;
505 skb_set_owner_r(skb, sk);
506
507 /* we escape from rcu protected region, make sure we dont leak
508 * a norefcounted dst
509 */
510 skb_dst_force(skb);
511
512 spin_lock_irqsave(&list->lock, flags);
513 sock_skb_set_dropcount(sk, skb);
514 __skb_queue_tail(list, skb);
515 spin_unlock_irqrestore(&list->lock, flags);
516
517 if (!sock_flag(sk, SOCK_DEAD))
518 sk->sk_data_ready(sk);
519 return 0;
520 }
521 EXPORT_SYMBOL(__sock_queue_rcv_skb);
522
523 enum skb_drop_reason
sock_queue_rcv_skb_reason(struct sock * sk,struct sk_buff * skb)524 sock_queue_rcv_skb_reason(struct sock *sk, struct sk_buff *skb)
525 {
526 enum skb_drop_reason drop_reason;
527 int err;
528
529 drop_reason = sk_filter_reason(sk, skb);
530 if (drop_reason)
531 return drop_reason;
532
533 err = __sock_queue_rcv_skb(sk, skb);
534 switch (err) {
535 case -ENOMEM:
536 return SKB_DROP_REASON_SOCKET_RCVBUFF;
537 case -ENOBUFS:
538 return SKB_DROP_REASON_PROTO_MEM;
539 }
540 return SKB_NOT_DROPPED_YET;
541 }
542 EXPORT_SYMBOL(sock_queue_rcv_skb_reason);
543
__sk_receive_skb(struct sock * sk,struct sk_buff * skb,const int nested,unsigned int trim_cap,bool refcounted)544 int __sk_receive_skb(struct sock *sk, struct sk_buff *skb,
545 const int nested, unsigned int trim_cap, bool refcounted)
546 {
547 enum skb_drop_reason reason;
548 int rc = NET_RX_SUCCESS;
549 int err;
550
551 reason = sk_filter_trim_cap(sk, skb, trim_cap);
552 if (reason)
553 goto discard_and_relse;
554
555 skb->dev = NULL;
556
557 if (sk_rcvqueues_full(sk, READ_ONCE(sk->sk_rcvbuf))) {
558 sk_drops_inc(sk);
559 reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
560 goto discard_and_relse;
561 }
562 if (nested)
563 bh_lock_sock_nested(sk);
564 else
565 bh_lock_sock(sk);
566 if (!sock_owned_by_user(sk)) {
567 /*
568 * trylock + unlock semantics:
569 */
570 mutex_acquire(&sk->sk_lock.dep_map, 0, 1, _RET_IP_);
571
572 rc = sk_backlog_rcv(sk, skb);
573
574 mutex_release(&sk->sk_lock.dep_map, _RET_IP_);
575 } else if ((err = sk_add_backlog(sk, skb, READ_ONCE(sk->sk_rcvbuf)))) {
576 bh_unlock_sock(sk);
577 if (err == -ENOMEM)
578 reason = SKB_DROP_REASON_PFMEMALLOC;
579 if (err == -ENOBUFS)
580 reason = SKB_DROP_REASON_SOCKET_BACKLOG;
581 sk_drops_inc(sk);
582 goto discard_and_relse;
583 }
584
585 bh_unlock_sock(sk);
586 out:
587 if (refcounted)
588 sock_put(sk);
589 return rc;
590 discard_and_relse:
591 sk_skb_reason_drop(sk, skb, reason);
592 goto out;
593 }
594 EXPORT_SYMBOL(__sk_receive_skb);
595
596 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ip6_dst_check(struct dst_entry *,
597 u32));
598 INDIRECT_CALLABLE_DECLARE(struct dst_entry *ipv4_dst_check(struct dst_entry *,
599 u32));
__sk_dst_check(struct sock * sk,u32 cookie)600 struct dst_entry *__sk_dst_check(struct sock *sk, u32 cookie)
601 {
602 struct dst_entry *dst = __sk_dst_get(sk);
603
604 if (dst && READ_ONCE(dst->obsolete) &&
605 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
606 dst, cookie) == NULL) {
607 sk_tx_queue_clear(sk);
608 WRITE_ONCE(sk->sk_dst_pending_confirm, 0);
609 RCU_INIT_POINTER(sk->sk_dst_cache, NULL);
610 dst_release(dst);
611 return NULL;
612 }
613
614 return dst;
615 }
616 EXPORT_SYMBOL(__sk_dst_check);
617
sk_dst_check(struct sock * sk,u32 cookie)618 struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
619 {
620 struct dst_entry *dst = sk_dst_get(sk);
621
622 if (dst && READ_ONCE(dst->obsolete) &&
623 INDIRECT_CALL_INET(dst->ops->check, ip6_dst_check, ipv4_dst_check,
624 dst, cookie) == NULL) {
625 sk_dst_reset(sk);
626 dst_release(dst);
627 return NULL;
628 }
629
630 return dst;
631 }
632 EXPORT_SYMBOL(sk_dst_check);
633
sock_bindtoindex_locked(struct sock * sk,int ifindex)634 static int sock_bindtoindex_locked(struct sock *sk, int ifindex)
635 {
636 int ret = -ENOPROTOOPT;
637 #ifdef CONFIG_NETDEVICES
638 struct net *net = sock_net(sk);
639
640 /* Sorry... */
641 ret = -EPERM;
642 if (sk->sk_bound_dev_if && !ns_capable(net->user_ns, CAP_NET_RAW))
643 goto out;
644
645 ret = -EINVAL;
646 if (ifindex < 0)
647 goto out;
648
649 /* Paired with all READ_ONCE() done locklessly. */
650 WRITE_ONCE(sk->sk_bound_dev_if, ifindex);
651
652 if (sk->sk_prot->rehash)
653 sk->sk_prot->rehash(sk);
654 sk_dst_reset(sk);
655
656 ret = 0;
657
658 out:
659 #endif
660
661 return ret;
662 }
663
sock_bindtoindex(struct sock * sk,int ifindex,bool lock_sk)664 int sock_bindtoindex(struct sock *sk, int ifindex, bool lock_sk)
665 {
666 int ret;
667
668 if (lock_sk)
669 lock_sock(sk);
670 ret = sock_bindtoindex_locked(sk, ifindex);
671 if (lock_sk)
672 release_sock(sk);
673
674 return ret;
675 }
676 EXPORT_SYMBOL(sock_bindtoindex);
677
sock_setbindtodevice(struct sock * sk,sockptr_t optval,int optlen)678 static int sock_setbindtodevice(struct sock *sk, sockptr_t optval, int optlen)
679 {
680 int ret = -ENOPROTOOPT;
681 #ifdef CONFIG_NETDEVICES
682 struct net *net = sock_net(sk);
683 char devname[IFNAMSIZ];
684 int index;
685
686 ret = -EINVAL;
687 if (optlen < 0)
688 goto out;
689
690 /* Bind this socket to a particular device like "eth0",
691 * as specified in the passed interface name. If the
692 * name is "" or the option length is zero the socket
693 * is not bound.
694 */
695 if (optlen > IFNAMSIZ - 1)
696 optlen = IFNAMSIZ - 1;
697 memset(devname, 0, sizeof(devname));
698
699 ret = -EFAULT;
700 if (copy_from_sockptr(devname, optval, optlen))
701 goto out;
702
703 index = 0;
704 if (devname[0] != '\0') {
705 struct net_device *dev;
706
707 rcu_read_lock();
708 dev = dev_get_by_name_rcu(net, devname);
709 if (dev)
710 index = dev->ifindex;
711 rcu_read_unlock();
712 ret = -ENODEV;
713 if (!dev)
714 goto out;
715 }
716
717 sockopt_lock_sock(sk);
718 ret = sock_bindtoindex_locked(sk, index);
719 sockopt_release_sock(sk);
720 out:
721 #endif
722
723 return ret;
724 }
725
sock_getbindtodevice(struct sock * sk,sockptr_t optval,sockptr_t optlen,int len)726 static int sock_getbindtodevice(struct sock *sk, sockptr_t optval,
727 sockptr_t optlen, int len)
728 {
729 int ret = -ENOPROTOOPT;
730 #ifdef CONFIG_NETDEVICES
731 int bound_dev_if = READ_ONCE(sk->sk_bound_dev_if);
732 struct net *net = sock_net(sk);
733 char devname[IFNAMSIZ];
734
735 if (bound_dev_if == 0) {
736 len = 0;
737 goto zero;
738 }
739
740 ret = -EINVAL;
741 if (len < IFNAMSIZ)
742 goto out;
743
744 ret = netdev_get_name(net, devname, bound_dev_if);
745 if (ret)
746 goto out;
747
748 len = strlen(devname) + 1;
749
750 ret = -EFAULT;
751 if (copy_to_sockptr(optval, devname, len))
752 goto out;
753
754 zero:
755 ret = -EFAULT;
756 if (copy_to_sockptr(optlen, &len, sizeof(int)))
757 goto out;
758
759 ret = 0;
760
761 out:
762 #endif
763
764 return ret;
765 }
766
sk_mc_loop(const struct sock * sk)767 bool sk_mc_loop(const struct sock *sk)
768 {
769 if (dev_recursion_level())
770 return false;
771 if (!sk)
772 return true;
773 /* IPV6_ADDRFORM can change sk->sk_family under us. */
774 switch (READ_ONCE(sk->sk_family)) {
775 case AF_INET:
776 return inet_test_bit(MC_LOOP, sk);
777 #if IS_ENABLED(CONFIG_IPV6)
778 case AF_INET6:
779 return inet6_test_bit(MC6_LOOP, sk);
780 #endif
781 }
782 WARN_ON_ONCE(1);
783 return true;
784 }
785 EXPORT_SYMBOL(sk_mc_loop);
786
sock_set_reuseaddr(struct sock * sk)787 void sock_set_reuseaddr(struct sock *sk)
788 {
789 lock_sock(sk);
790 sk->sk_reuse = SK_CAN_REUSE;
791 release_sock(sk);
792 }
793 EXPORT_SYMBOL(sock_set_reuseaddr);
794
sock_set_reuseport(struct sock * sk)795 void sock_set_reuseport(struct sock *sk)
796 {
797 lock_sock(sk);
798 sk->sk_reuseport = true;
799 release_sock(sk);
800 }
801 EXPORT_SYMBOL(sock_set_reuseport);
802
sock_no_linger(struct sock * sk)803 void sock_no_linger(struct sock *sk)
804 {
805 lock_sock(sk);
806 WRITE_ONCE(sk->sk_lingertime, 0);
807 sock_set_flag(sk, SOCK_LINGER);
808 release_sock(sk);
809 }
810 EXPORT_SYMBOL(sock_no_linger);
811
sock_set_priority(struct sock * sk,u32 priority)812 void sock_set_priority(struct sock *sk, u32 priority)
813 {
814 WRITE_ONCE(sk->sk_priority, priority);
815 }
816 EXPORT_SYMBOL(sock_set_priority);
817
sock_set_sndtimeo(struct sock * sk,s64 secs)818 void sock_set_sndtimeo(struct sock *sk, s64 secs)
819 {
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 }
825 EXPORT_SYMBOL(sock_set_sndtimeo);
826
__sock_set_timestamps(struct sock * sk,bool val,bool new,bool ns)827 static void __sock_set_timestamps(struct sock *sk, bool val, bool new, bool ns)
828 {
829 sock_valbool_flag(sk, SOCK_RCVTSTAMP, val);
830 sock_valbool_flag(sk, SOCK_RCVTSTAMPNS, val && ns);
831 if (val) {
832 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, new);
833 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
834 }
835 }
836
sock_set_timestamp(struct sock * sk,int optname,bool valbool)837 void sock_set_timestamp(struct sock *sk, int optname, bool valbool)
838 {
839 switch (optname) {
840 case SO_TIMESTAMP_OLD:
841 __sock_set_timestamps(sk, valbool, false, false);
842 break;
843 case SO_TIMESTAMP_NEW:
844 __sock_set_timestamps(sk, valbool, true, false);
845 break;
846 case SO_TIMESTAMPNS_OLD:
847 __sock_set_timestamps(sk, valbool, false, true);
848 break;
849 case SO_TIMESTAMPNS_NEW:
850 __sock_set_timestamps(sk, valbool, true, true);
851 break;
852 }
853 }
854
sock_timestamping_bind_phc(struct sock * sk,int phc_index)855 static int sock_timestamping_bind_phc(struct sock *sk, int phc_index)
856 {
857 struct net *net = sock_net(sk);
858 struct net_device *dev = NULL;
859 bool match = false;
860 int *vclock_index;
861 int i, num;
862
863 if (sk->sk_bound_dev_if)
864 dev = dev_get_by_index(net, sk->sk_bound_dev_if);
865
866 if (!dev) {
867 pr_err("%s: sock not bind to device\n", __func__);
868 return -EOPNOTSUPP;
869 }
870
871 num = ethtool_get_phc_vclocks(dev, &vclock_index);
872 dev_put(dev);
873
874 for (i = 0; i < num; i++) {
875 if (*(vclock_index + i) == phc_index) {
876 match = true;
877 break;
878 }
879 }
880
881 if (num > 0)
882 kfree(vclock_index);
883
884 if (!match)
885 return -EINVAL;
886
887 WRITE_ONCE(sk->sk_bind_phc, phc_index);
888
889 return 0;
890 }
891
sock_set_timestamping(struct sock * sk,int optname,struct so_timestamping timestamping)892 int sock_set_timestamping(struct sock *sk, int optname,
893 struct so_timestamping timestamping)
894 {
895 int val = timestamping.flags;
896 int ret;
897
898 if (val & ~SOF_TIMESTAMPING_MASK)
899 return -EINVAL;
900
901 if (val & SOF_TIMESTAMPING_OPT_ID_TCP &&
902 !(val & SOF_TIMESTAMPING_OPT_ID))
903 return -EINVAL;
904
905 if (val & SOF_TIMESTAMPING_OPT_ID &&
906 !(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)) {
907 if (sk_is_tcp(sk)) {
908 if ((1 << sk->sk_state) &
909 (TCPF_CLOSE | TCPF_LISTEN))
910 return -EINVAL;
911 if (val & SOF_TIMESTAMPING_OPT_ID_TCP)
912 atomic_set(&sk->sk_tskey, tcp_sk(sk)->write_seq);
913 else
914 atomic_set(&sk->sk_tskey, tcp_sk(sk)->snd_una);
915 } else {
916 atomic_set(&sk->sk_tskey, 0);
917 }
918 }
919
920 if (val & SOF_TIMESTAMPING_OPT_STATS &&
921 !(val & SOF_TIMESTAMPING_OPT_TSONLY))
922 return -EINVAL;
923
924 if (val & SOF_TIMESTAMPING_BIND_PHC) {
925 ret = sock_timestamping_bind_phc(sk, timestamping.bind_phc);
926 if (ret)
927 return ret;
928 }
929
930 WRITE_ONCE(sk->sk_tsflags, val);
931 sock_valbool_flag(sk, SOCK_TSTAMP_NEW, optname == SO_TIMESTAMPING_NEW);
932 sock_valbool_flag(sk, SOCK_TIMESTAMPING_ANY, !!(val & TSFLAGS_ANY));
933
934 if (val & SOF_TIMESTAMPING_RX_SOFTWARE)
935 sock_enable_timestamp(sk,
936 SOCK_TIMESTAMPING_RX_SOFTWARE);
937 else
938 sock_disable_timestamp(sk,
939 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE));
940 return 0;
941 }
942
943 #if defined(CONFIG_CGROUP_BPF)
bpf_skops_tx_timestamping(struct sock * sk,struct sk_buff * skb,int op)944 void bpf_skops_tx_timestamping(struct sock *sk, struct sk_buff *skb, int op)
945 {
946 struct bpf_sock_ops_kern sock_ops;
947
948 memset(&sock_ops, 0, offsetof(struct bpf_sock_ops_kern, temp));
949 sock_ops.op = op;
950 sock_ops.is_fullsock = 1;
951 sock_ops.sk = sk;
952 bpf_skops_init_skb(&sock_ops, skb, 0);
953 __cgroup_bpf_run_filter_sock_ops(sk, &sock_ops, CGROUP_SOCK_OPS);
954 }
955 #endif
956
sock_set_keepalive(struct sock * sk)957 void sock_set_keepalive(struct sock *sk)
958 {
959 lock_sock(sk);
960 if (sk->sk_prot->keepalive)
961 sk->sk_prot->keepalive(sk, true);
962 sock_valbool_flag(sk, SOCK_KEEPOPEN, true);
963 release_sock(sk);
964 }
965 EXPORT_SYMBOL(sock_set_keepalive);
966
__sock_set_rcvbuf(struct sock * sk,int val)967 static void __sock_set_rcvbuf(struct sock *sk, int val)
968 {
969 struct socket *sock = sk->sk_socket;
970
971 /* Ensure val * 2 fits into an int, to prevent max_t() from treating it
972 * as a negative value.
973 */
974 val = min_t(int, val, INT_MAX / 2);
975 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
976
977 /* We double it on the way in to account for "struct sk_buff" etc.
978 * overhead. Applications assume that the SO_RCVBUF setting they make
979 * will allow that much actual data to be received on that socket.
980 *
981 * Applications are unaware that "struct sk_buff" and other overheads
982 * allocate from the receive buffer during socket buffer allocation.
983 *
984 * And after considering the possible alternatives, returning the value
985 * we actually used in getsockopt is the most desirable behavior.
986 */
987 WRITE_ONCE(sk->sk_rcvbuf, max_t(int, val * 2, SOCK_MIN_RCVBUF));
988
989 if (sock) {
990 const struct proto_ops *ops = READ_ONCE(sock->ops);
991
992 if (ops->set_rcvbuf)
993 ops->set_rcvbuf(sk, sk->sk_rcvbuf);
994 }
995 }
996
sock_set_rcvbuf(struct sock * sk,int val)997 void sock_set_rcvbuf(struct sock *sk, int val)
998 {
999 lock_sock(sk);
1000 __sock_set_rcvbuf(sk, val);
1001 release_sock(sk);
1002 }
1003 EXPORT_SYMBOL(sock_set_rcvbuf);
1004
__sock_set_mark(struct sock * sk,u32 val)1005 static void __sock_set_mark(struct sock *sk, u32 val)
1006 {
1007 if (val != sk->sk_mark) {
1008 WRITE_ONCE(sk->sk_mark, val);
1009 sk_dst_reset(sk);
1010 }
1011 }
1012
sock_set_mark(struct sock * sk,u32 val)1013 void sock_set_mark(struct sock *sk, u32 val)
1014 {
1015 lock_sock(sk);
1016 __sock_set_mark(sk, val);
1017 release_sock(sk);
1018 }
1019 EXPORT_SYMBOL(sock_set_mark);
1020
sock_release_reserved_memory(struct sock * sk,int bytes)1021 static void sock_release_reserved_memory(struct sock *sk, int bytes)
1022 {
1023 /* Round down bytes to multiple of pages */
1024 bytes = round_down(bytes, PAGE_SIZE);
1025
1026 WARN_ON(bytes > sk->sk_reserved_mem);
1027 WRITE_ONCE(sk->sk_reserved_mem, sk->sk_reserved_mem - bytes);
1028 sk_mem_reclaim(sk);
1029 }
1030
sock_reserve_memory(struct sock * sk,int bytes)1031 static int sock_reserve_memory(struct sock *sk, int bytes)
1032 {
1033 long allocated;
1034 bool charged;
1035 int pages;
1036
1037 if (!mem_cgroup_sk_enabled(sk) || !sk_has_account(sk))
1038 return -EOPNOTSUPP;
1039
1040 if (!bytes)
1041 return 0;
1042
1043 pages = sk_mem_pages(bytes);
1044
1045 /* pre-charge to memcg */
1046 charged = mem_cgroup_sk_charge(sk, pages,
1047 GFP_KERNEL | __GFP_RETRY_MAYFAIL);
1048 if (!charged)
1049 return -ENOMEM;
1050
1051 if (sk->sk_bypass_prot_mem)
1052 goto success;
1053
1054 /* pre-charge to forward_alloc */
1055 sk_memory_allocated_add(sk, pages);
1056 allocated = sk_memory_allocated(sk);
1057
1058 /* If the system goes into memory pressure with this
1059 * precharge, give up and return error.
1060 */
1061 if (allocated > sk_prot_mem_limits(sk, 1)) {
1062 sk_memory_allocated_sub(sk, pages);
1063 mem_cgroup_sk_uncharge(sk, pages);
1064 return -ENOMEM;
1065 }
1066
1067 success:
1068 sk_forward_alloc_add(sk, pages << PAGE_SHIFT);
1069
1070 WRITE_ONCE(sk->sk_reserved_mem,
1071 sk->sk_reserved_mem + (pages << PAGE_SHIFT));
1072
1073 return 0;
1074 }
1075
1076 #ifdef CONFIG_PAGE_POOL
1077
1078 /* This is the number of tokens and frags that the user can SO_DEVMEM_DONTNEED
1079 * in 1 syscall. The limit exists to limit the amount of memory the kernel
1080 * allocates to copy these tokens, and to prevent looping over the frags for
1081 * too long.
1082 */
1083 #define MAX_DONTNEED_TOKENS 128
1084 #define MAX_DONTNEED_FRAGS 1024
1085
1086 static noinline_for_stack int
sock_devmem_dontneed(struct sock * sk,sockptr_t optval,unsigned int optlen)1087 sock_devmem_dontneed(struct sock *sk, sockptr_t optval, unsigned int optlen)
1088 {
1089 unsigned int num_tokens, i, j, k, netmem_num = 0;
1090 struct dmabuf_token *tokens;
1091 int ret = 0, num_frags = 0;
1092 netmem_ref netmems[16];
1093
1094 if (!sk_is_tcp(sk))
1095 return -EBADF;
1096
1097 if (optlen % sizeof(*tokens) ||
1098 optlen > sizeof(*tokens) * MAX_DONTNEED_TOKENS)
1099 return -EINVAL;
1100
1101 num_tokens = optlen / sizeof(*tokens);
1102 tokens = kvmalloc_objs(*tokens, num_tokens);
1103 if (!tokens)
1104 return -ENOMEM;
1105
1106 if (copy_from_sockptr(tokens, optval, optlen)) {
1107 kvfree(tokens);
1108 return -EFAULT;
1109 }
1110
1111 xa_lock_bh(&sk->sk_user_frags);
1112 for (i = 0; i < num_tokens; i++) {
1113 for (j = 0; j < tokens[i].token_count; j++) {
1114 if (++num_frags > MAX_DONTNEED_FRAGS)
1115 goto frag_limit_reached;
1116
1117 netmem_ref netmem = (__force netmem_ref)__xa_erase(
1118 &sk->sk_user_frags, tokens[i].token_start + j);
1119
1120 if (!netmem || WARN_ON_ONCE(!netmem_is_net_iov(netmem)))
1121 continue;
1122
1123 netmems[netmem_num++] = netmem;
1124 if (netmem_num == ARRAY_SIZE(netmems)) {
1125 xa_unlock_bh(&sk->sk_user_frags);
1126 for (k = 0; k < netmem_num; k++)
1127 WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1128 netmem_num = 0;
1129 xa_lock_bh(&sk->sk_user_frags);
1130 }
1131 ret++;
1132 }
1133 }
1134
1135 frag_limit_reached:
1136 xa_unlock_bh(&sk->sk_user_frags);
1137 for (k = 0; k < netmem_num; k++)
1138 WARN_ON_ONCE(!napi_pp_put_page(netmems[k]));
1139
1140 kvfree(tokens);
1141 return ret;
1142 }
1143 #endif
1144
sockopt_lock_sock(struct sock * sk)1145 void sockopt_lock_sock(struct sock *sk)
1146 {
1147 /* When current->bpf_ctx is set, the setsockopt is called from
1148 * a bpf prog. bpf has ensured the sk lock has been
1149 * acquired before calling setsockopt().
1150 */
1151 if (has_current_bpf_ctx())
1152 return;
1153
1154 lock_sock(sk);
1155 }
1156 EXPORT_SYMBOL(sockopt_lock_sock);
1157
sockopt_release_sock(struct sock * sk)1158 void sockopt_release_sock(struct sock *sk)
1159 {
1160 if (has_current_bpf_ctx())
1161 return;
1162
1163 release_sock(sk);
1164 }
1165 EXPORT_SYMBOL(sockopt_release_sock);
1166
sockopt_ns_capable(struct user_namespace * ns,int cap)1167 bool sockopt_ns_capable(struct user_namespace *ns, int cap)
1168 {
1169 return has_current_bpf_ctx() || ns_capable(ns, cap);
1170 }
1171 EXPORT_SYMBOL(sockopt_ns_capable);
1172
sockopt_capable(int cap)1173 bool sockopt_capable(int cap)
1174 {
1175 return has_current_bpf_ctx() || capable(cap);
1176 }
1177 EXPORT_SYMBOL(sockopt_capable);
1178
sockopt_validate_clockid(__kernel_clockid_t value)1179 static int sockopt_validate_clockid(__kernel_clockid_t value)
1180 {
1181 switch (value) {
1182 case CLOCK_REALTIME:
1183 case CLOCK_MONOTONIC:
1184 case CLOCK_TAI:
1185 return 0;
1186 }
1187 return -EINVAL;
1188 }
1189
1190 /*
1191 * This is meant for all protocols to use and covers goings on
1192 * at the socket level. Everything here is generic.
1193 */
1194
sk_setsockopt(struct sock * sk,int level,int optname,sockptr_t optval,unsigned int optlen)1195 int sk_setsockopt(struct sock *sk, int level, int optname,
1196 sockptr_t optval, unsigned int optlen)
1197 {
1198 struct so_timestamping timestamping;
1199 struct socket *sock = sk->sk_socket;
1200 struct sock_txtime sk_txtime;
1201 int val;
1202 int valbool;
1203 struct linger ling;
1204 int ret = 0;
1205
1206 /*
1207 * Options without arguments
1208 */
1209
1210 if (optname == SO_BINDTODEVICE)
1211 return sock_setbindtodevice(sk, optval, optlen);
1212
1213 if (optlen < sizeof(int))
1214 return -EINVAL;
1215
1216 if (copy_from_sockptr(&val, optval, sizeof(val)))
1217 return -EFAULT;
1218
1219 valbool = val ? 1 : 0;
1220
1221 /* handle options which do not require locking the socket. */
1222 switch (optname) {
1223 case SO_PRIORITY:
1224 if (sk_set_prio_allowed(sk, val)) {
1225 sock_set_priority(sk, val);
1226 return 0;
1227 }
1228 return -EPERM;
1229 case SO_TYPE:
1230 case SO_PROTOCOL:
1231 case SO_DOMAIN:
1232 case SO_ERROR:
1233 return -ENOPROTOOPT;
1234 #ifdef CONFIG_NET_RX_BUSY_POLL
1235 case SO_BUSY_POLL:
1236 if (val < 0)
1237 return -EINVAL;
1238 WRITE_ONCE(sk->sk_ll_usec, val);
1239 return 0;
1240 case SO_PREFER_BUSY_POLL:
1241 if (valbool && !sockopt_capable(CAP_NET_ADMIN))
1242 return -EPERM;
1243 WRITE_ONCE(sk->sk_prefer_busy_poll, valbool);
1244 return 0;
1245 case SO_BUSY_POLL_BUDGET:
1246 if (val > READ_ONCE(sk->sk_busy_poll_budget) &&
1247 !sockopt_capable(CAP_NET_ADMIN))
1248 return -EPERM;
1249 if (val < 0 || val > U16_MAX)
1250 return -EINVAL;
1251 WRITE_ONCE(sk->sk_busy_poll_budget, val);
1252 return 0;
1253 #endif
1254 case SO_MAX_PACING_RATE:
1255 {
1256 unsigned long ulval = (val == ~0U) ? ~0UL : (unsigned int)val;
1257 unsigned long pacing_rate;
1258
1259 if (sizeof(ulval) != sizeof(val) &&
1260 optlen >= sizeof(ulval) &&
1261 copy_from_sockptr(&ulval, optval, sizeof(ulval))) {
1262 return -EFAULT;
1263 }
1264 if (ulval != ~0UL)
1265 cmpxchg(&sk->sk_pacing_status,
1266 SK_PACING_NONE,
1267 SK_PACING_NEEDED);
1268 /* Pairs with READ_ONCE() from sk_getsockopt() */
1269 WRITE_ONCE(sk->sk_max_pacing_rate, ulval);
1270 pacing_rate = READ_ONCE(sk->sk_pacing_rate);
1271 if (ulval < pacing_rate)
1272 WRITE_ONCE(sk->sk_pacing_rate, ulval);
1273 return 0;
1274 }
1275 case SO_TXREHASH:
1276 if (!sk_is_tcp(sk))
1277 return -EOPNOTSUPP;
1278 if (val < -1 || val > 1)
1279 return -EINVAL;
1280 if ((u8)val == SOCK_TXREHASH_DEFAULT)
1281 val = READ_ONCE(sock_net(sk)->core.sysctl_txrehash);
1282 /* Paired with READ_ONCE() in tcp_rtx_synack()
1283 * and sk_getsockopt().
1284 */
1285 WRITE_ONCE(sk->sk_txrehash, (u8)val);
1286 return 0;
1287 case SO_PEEK_OFF:
1288 {
1289 int (*set_peek_off)(struct sock *sk, int val);
1290
1291 set_peek_off = READ_ONCE(sock->ops)->set_peek_off;
1292 if (set_peek_off)
1293 ret = set_peek_off(sk, val);
1294 else
1295 ret = -EOPNOTSUPP;
1296 return ret;
1297 }
1298 #ifdef CONFIG_PAGE_POOL
1299 case SO_DEVMEM_DONTNEED:
1300 return sock_devmem_dontneed(sk, optval, optlen);
1301 #endif
1302 case SO_SNDTIMEO_OLD:
1303 case SO_SNDTIMEO_NEW:
1304 return sock_set_timeout(&sk->sk_sndtimeo, optval,
1305 optlen, optname == SO_SNDTIMEO_OLD);
1306 case SO_RCVTIMEO_OLD:
1307 case SO_RCVTIMEO_NEW:
1308 return sock_set_timeout(&sk->sk_rcvtimeo, optval,
1309 optlen, optname == SO_RCVTIMEO_OLD);
1310 }
1311
1312 sockopt_lock_sock(sk);
1313
1314 switch (optname) {
1315 case SO_DEBUG:
1316 if (val && !sockopt_capable(CAP_NET_ADMIN))
1317 ret = -EACCES;
1318 else
1319 sock_valbool_flag(sk, SOCK_DBG, valbool);
1320 break;
1321 case SO_REUSEADDR:
1322 sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
1323 break;
1324 case SO_REUSEPORT:
1325 if (valbool && !sk_is_inet(sk))
1326 ret = -EOPNOTSUPP;
1327 else
1328 sk->sk_reuseport = valbool;
1329 break;
1330 case SO_DONTROUTE:
1331 sock_valbool_flag(sk, SOCK_LOCALROUTE, valbool);
1332 sk_dst_reset(sk);
1333 break;
1334 case SO_BROADCAST:
1335 sock_valbool_flag(sk, SOCK_BROADCAST, valbool);
1336 break;
1337 case SO_SNDBUF:
1338 /* Don't error on this BSD doesn't and if you think
1339 * about it this is right. Otherwise apps have to
1340 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1341 * are treated in BSD as hints
1342 */
1343 val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
1344 set_sndbuf:
1345 /* Ensure val * 2 fits into an int, to prevent max_t()
1346 * from treating it as a negative value.
1347 */
1348 val = min_t(int, val, INT_MAX / 2);
1349 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
1350 WRITE_ONCE(sk->sk_sndbuf,
1351 max_t(int, val * 2, SOCK_MIN_SNDBUF));
1352 /* Wake up sending tasks if we upped the value. */
1353 sk->sk_write_space(sk);
1354 break;
1355
1356 case SO_SNDBUFFORCE:
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 if (val < 0)
1366 val = 0;
1367 goto set_sndbuf;
1368
1369 case SO_RCVBUF:
1370 /* Don't error on this BSD doesn't and if you think
1371 * about it this is right. Otherwise apps have to
1372 * play 'guess the biggest size' games. RCVBUF/SNDBUF
1373 * are treated in BSD as hints
1374 */
1375 __sock_set_rcvbuf(sk, min_t(u32, val, READ_ONCE(sysctl_rmem_max)));
1376 break;
1377
1378 case SO_RCVBUFFORCE:
1379 if (!sockopt_capable(CAP_NET_ADMIN)) {
1380 ret = -EPERM;
1381 break;
1382 }
1383
1384 /* No negative values (to prevent underflow, as val will be
1385 * multiplied by 2).
1386 */
1387 __sock_set_rcvbuf(sk, max(val, 0));
1388 break;
1389
1390 case SO_KEEPALIVE:
1391 if (sk->sk_prot->keepalive)
1392 sk->sk_prot->keepalive(sk, valbool);
1393 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
1394 break;
1395
1396 case SO_OOBINLINE:
1397 sock_valbool_flag(sk, SOCK_URGINLINE, valbool);
1398 break;
1399
1400 case SO_NO_CHECK:
1401 sk->sk_no_check_tx = valbool;
1402 break;
1403
1404 case SO_LINGER:
1405 if (optlen < sizeof(ling)) {
1406 ret = -EINVAL; /* 1003.1g */
1407 break;
1408 }
1409 if (copy_from_sockptr(&ling, optval, sizeof(ling))) {
1410 ret = -EFAULT;
1411 break;
1412 }
1413 if (!ling.l_onoff) {
1414 sock_reset_flag(sk, SOCK_LINGER);
1415 } else {
1416 unsigned long t_sec = ling.l_linger;
1417
1418 if (t_sec >= MAX_SCHEDULE_TIMEOUT / HZ)
1419 WRITE_ONCE(sk->sk_lingertime, MAX_SCHEDULE_TIMEOUT);
1420 else
1421 WRITE_ONCE(sk->sk_lingertime, t_sec * HZ);
1422 sock_set_flag(sk, SOCK_LINGER);
1423 }
1424 break;
1425
1426 case SO_BSDCOMPAT:
1427 break;
1428
1429 case SO_TIMESTAMP_OLD:
1430 case SO_TIMESTAMP_NEW:
1431 case SO_TIMESTAMPNS_OLD:
1432 case SO_TIMESTAMPNS_NEW:
1433 sock_set_timestamp(sk, optname, valbool);
1434 break;
1435
1436 case SO_TIMESTAMPING_NEW:
1437 case SO_TIMESTAMPING_OLD:
1438 if (optlen == sizeof(timestamping)) {
1439 if (copy_from_sockptr(×tamping, optval,
1440 sizeof(timestamping))) {
1441 ret = -EFAULT;
1442 break;
1443 }
1444 } else {
1445 memset(×tamping, 0, sizeof(timestamping));
1446 timestamping.flags = val;
1447 }
1448 ret = sock_set_timestamping(sk, optname, timestamping);
1449 break;
1450
1451 case SO_RCVLOWAT:
1452 {
1453 int (*set_rcvlowat)(struct sock *sk, int val) = NULL;
1454
1455 if (val < 0)
1456 val = INT_MAX;
1457 if (sock)
1458 set_rcvlowat = READ_ONCE(sock->ops)->set_rcvlowat;
1459 if (set_rcvlowat)
1460 ret = set_rcvlowat(sk, val);
1461 else
1462 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
1463 break;
1464 }
1465 case SO_ATTACH_FILTER: {
1466 struct sock_fprog fprog;
1467
1468 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1469 if (!ret)
1470 ret = sk_attach_filter(&fprog, sk);
1471 break;
1472 }
1473 case SO_ATTACH_BPF:
1474 ret = -EINVAL;
1475 if (optlen == sizeof(u32)) {
1476 u32 ufd;
1477
1478 ret = -EFAULT;
1479 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1480 break;
1481
1482 ret = sk_attach_bpf(ufd, sk);
1483 }
1484 break;
1485
1486 case SO_ATTACH_REUSEPORT_CBPF: {
1487 struct sock_fprog fprog;
1488
1489 ret = copy_bpf_fprog_from_user(&fprog, optval, optlen);
1490 if (!ret)
1491 ret = sk_reuseport_attach_filter(&fprog, sk);
1492 break;
1493 }
1494 case SO_ATTACH_REUSEPORT_EBPF:
1495 ret = -EINVAL;
1496 if (optlen == sizeof(u32)) {
1497 u32 ufd;
1498
1499 ret = -EFAULT;
1500 if (copy_from_sockptr(&ufd, optval, sizeof(ufd)))
1501 break;
1502
1503 ret = sk_reuseport_attach_bpf(ufd, sk);
1504 }
1505 break;
1506
1507 case SO_DETACH_REUSEPORT_BPF:
1508 ret = reuseport_detach_prog(sk);
1509 break;
1510
1511 case SO_DETACH_FILTER:
1512 ret = sk_detach_filter(sk);
1513 break;
1514
1515 case SO_LOCK_FILTER:
1516 if (sock_flag(sk, SOCK_FILTER_LOCKED) && !valbool)
1517 ret = -EPERM;
1518 else
1519 sock_valbool_flag(sk, SOCK_FILTER_LOCKED, valbool);
1520 break;
1521
1522 case SO_MARK:
1523 if (!sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
1524 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1525 ret = -EPERM;
1526 break;
1527 }
1528
1529 __sock_set_mark(sk, val);
1530 break;
1531 case SO_RCVMARK:
1532 sock_valbool_flag(sk, SOCK_RCVMARK, valbool);
1533 break;
1534
1535 case SO_RCVPRIORITY:
1536 sock_valbool_flag(sk, SOCK_RCVPRIORITY, valbool);
1537 break;
1538
1539 case SO_RXQ_OVFL:
1540 sock_valbool_flag(sk, SOCK_RXQ_OVFL, valbool);
1541 break;
1542
1543 case SO_WIFI_STATUS:
1544 sock_valbool_flag(sk, SOCK_WIFI_STATUS, valbool);
1545 break;
1546
1547 case SO_NOFCS:
1548 sock_valbool_flag(sk, SOCK_NOFCS, valbool);
1549 break;
1550
1551 case SO_SELECT_ERR_QUEUE:
1552 sock_valbool_flag(sk, SOCK_SELECT_ERR_QUEUE, valbool);
1553 break;
1554
1555 case SO_PASSCRED:
1556 if (sk_may_scm_recv(sk))
1557 sk->sk_scm_credentials = valbool;
1558 else
1559 ret = -EOPNOTSUPP;
1560 break;
1561
1562 case SO_PASSSEC:
1563 if (IS_ENABLED(CONFIG_SECURITY_NETWORK) && sk_may_scm_recv(sk))
1564 sk->sk_scm_security = valbool;
1565 else
1566 ret = -EOPNOTSUPP;
1567 break;
1568
1569 case SO_PASSPIDFD:
1570 if (sk_is_unix(sk))
1571 sk->sk_scm_pidfd = valbool;
1572 else
1573 ret = -EOPNOTSUPP;
1574 break;
1575
1576 case SO_PASSRIGHTS:
1577 if (sk_is_unix(sk))
1578 sk->sk_scm_rights = valbool;
1579 else
1580 ret = -EOPNOTSUPP;
1581 break;
1582
1583 case SO_INCOMING_CPU:
1584 reuseport_update_incoming_cpu(sk, val);
1585 break;
1586
1587 case SO_CNX_ADVICE:
1588 if (val == 1)
1589 dst_negative_advice(sk);
1590 break;
1591
1592 case SO_ZEROCOPY:
1593 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6) {
1594 if (!(sk_is_tcp(sk) ||
1595 (sk->sk_type == SOCK_DGRAM &&
1596 sk->sk_protocol == IPPROTO_UDP)))
1597 ret = -EOPNOTSUPP;
1598 } else if (sk->sk_family != PF_RDS) {
1599 ret = -EOPNOTSUPP;
1600 }
1601 if (!ret) {
1602 if (val < 0 || val > 1)
1603 ret = -EINVAL;
1604 else
1605 sock_valbool_flag(sk, SOCK_ZEROCOPY, valbool);
1606 }
1607 break;
1608
1609 case SO_TXTIME:
1610 if (optlen != sizeof(struct sock_txtime)) {
1611 ret = -EINVAL;
1612 break;
1613 } else if (copy_from_sockptr(&sk_txtime, optval,
1614 sizeof(struct sock_txtime))) {
1615 ret = -EFAULT;
1616 break;
1617 } else if (sk_txtime.flags & ~SOF_TXTIME_FLAGS_MASK) {
1618 ret = -EINVAL;
1619 break;
1620 }
1621 /* CLOCK_MONOTONIC is only used by sch_fq, and this packet
1622 * scheduler has enough safe guards.
1623 */
1624 if (sk_txtime.clockid != CLOCK_MONOTONIC &&
1625 !sockopt_ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) {
1626 ret = -EPERM;
1627 break;
1628 }
1629
1630 ret = sockopt_validate_clockid(sk_txtime.clockid);
1631 if (ret)
1632 break;
1633
1634 sock_valbool_flag(sk, SOCK_TXTIME, true);
1635 sk->sk_clockid = sk_txtime.clockid;
1636 sk->sk_txtime_deadline_mode =
1637 !!(sk_txtime.flags & SOF_TXTIME_DEADLINE_MODE);
1638 sk->sk_txtime_report_errors =
1639 !!(sk_txtime.flags & SOF_TXTIME_REPORT_ERRORS);
1640 break;
1641
1642 case SO_BINDTOIFINDEX:
1643 ret = sock_bindtoindex_locked(sk, val);
1644 break;
1645
1646 case SO_BUF_LOCK:
1647 if (val & ~SOCK_BUF_LOCK_MASK) {
1648 ret = -EINVAL;
1649 break;
1650 }
1651 sk->sk_userlocks = val | (sk->sk_userlocks &
1652 ~SOCK_BUF_LOCK_MASK);
1653 break;
1654
1655 case SO_RESERVE_MEM:
1656 {
1657 int delta;
1658
1659 if (val < 0) {
1660 ret = -EINVAL;
1661 break;
1662 }
1663
1664 delta = val - sk->sk_reserved_mem;
1665 if (delta < 0)
1666 sock_release_reserved_memory(sk, -delta);
1667 else
1668 ret = sock_reserve_memory(sk, delta);
1669 break;
1670 }
1671
1672 default:
1673 ret = -ENOPROTOOPT;
1674 break;
1675 }
1676 sockopt_release_sock(sk);
1677 return ret;
1678 }
1679
sock_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)1680 int sock_setsockopt(struct socket *sock, int level, int optname,
1681 sockptr_t optval, unsigned int optlen)
1682 {
1683 return sk_setsockopt(sock->sk, level, optname,
1684 optval, optlen);
1685 }
1686 EXPORT_SYMBOL(sock_setsockopt);
1687
sk_get_peer_cred(struct sock * sk)1688 static const struct cred *sk_get_peer_cred(struct sock *sk)
1689 {
1690 const struct cred *cred;
1691
1692 spin_lock(&sk->sk_peer_lock);
1693 cred = get_cred(sk->sk_peer_cred);
1694 spin_unlock(&sk->sk_peer_lock);
1695
1696 return cred;
1697 }
1698
cred_to_ucred(struct pid * pid,const struct cred * cred,struct ucred * ucred)1699 static void cred_to_ucred(struct pid *pid, const struct cred *cred,
1700 struct ucred *ucred)
1701 {
1702 ucred->pid = pid_vnr(pid);
1703 ucred->uid = ucred->gid = -1;
1704 if (cred) {
1705 struct user_namespace *current_ns = current_user_ns();
1706
1707 ucred->uid = from_kuid_munged(current_ns, cred->euid);
1708 ucred->gid = from_kgid_munged(current_ns, cred->egid);
1709 }
1710 }
1711
groups_to_user(sockptr_t dst,const struct group_info * src)1712 static int groups_to_user(sockptr_t dst, const struct group_info *src)
1713 {
1714 struct user_namespace *user_ns = current_user_ns();
1715 int i;
1716
1717 for (i = 0; i < src->ngroups; i++) {
1718 gid_t gid = from_kgid_munged(user_ns, src->gid[i]);
1719
1720 if (copy_to_sockptr_offset(dst, i * sizeof(gid), &gid, sizeof(gid)))
1721 return -EFAULT;
1722 }
1723
1724 return 0;
1725 }
1726
sk_getsockopt(struct sock * sk,int level,int optname,sockptr_t optval,sockptr_t optlen)1727 int sk_getsockopt(struct sock *sk, int level, int optname,
1728 sockptr_t optval, sockptr_t optlen)
1729 {
1730 struct socket *sock = sk->sk_socket;
1731
1732 union {
1733 int val;
1734 u64 val64;
1735 unsigned long ulval;
1736 struct linger ling;
1737 struct old_timeval32 tm32;
1738 struct __kernel_old_timeval tm;
1739 struct __kernel_sock_timeval stm;
1740 struct sock_txtime txtime;
1741 struct so_timestamping timestamping;
1742 } v;
1743
1744 int lv = sizeof(int);
1745 int len;
1746
1747 if (copy_from_sockptr(&len, optlen, sizeof(int)))
1748 return -EFAULT;
1749 if (len < 0)
1750 return -EINVAL;
1751
1752 memset(&v, 0, sizeof(v));
1753
1754 switch (optname) {
1755 case SO_DEBUG:
1756 v.val = sock_flag(sk, SOCK_DBG);
1757 break;
1758
1759 case SO_DONTROUTE:
1760 v.val = sock_flag(sk, SOCK_LOCALROUTE);
1761 break;
1762
1763 case SO_BROADCAST:
1764 v.val = sock_flag(sk, SOCK_BROADCAST);
1765 break;
1766
1767 case SO_SNDBUF:
1768 v.val = READ_ONCE(sk->sk_sndbuf);
1769 break;
1770
1771 case SO_RCVBUF:
1772 v.val = READ_ONCE(sk->sk_rcvbuf);
1773 break;
1774
1775 case SO_REUSEADDR:
1776 v.val = sk->sk_reuse;
1777 break;
1778
1779 case SO_REUSEPORT:
1780 v.val = sk->sk_reuseport;
1781 break;
1782
1783 case SO_KEEPALIVE:
1784 v.val = sock_flag(sk, SOCK_KEEPOPEN);
1785 break;
1786
1787 case SO_TYPE:
1788 v.val = sk->sk_type;
1789 break;
1790
1791 case SO_PROTOCOL:
1792 v.val = sk->sk_protocol;
1793 break;
1794
1795 case SO_DOMAIN:
1796 v.val = sk->sk_family;
1797 break;
1798
1799 case SO_ERROR:
1800 v.val = -sock_error(sk);
1801 if (v.val == 0)
1802 v.val = xchg(&sk->sk_err_soft, 0);
1803 break;
1804
1805 case SO_OOBINLINE:
1806 v.val = sock_flag(sk, SOCK_URGINLINE);
1807 break;
1808
1809 case SO_NO_CHECK:
1810 v.val = sk->sk_no_check_tx;
1811 break;
1812
1813 case SO_PRIORITY:
1814 v.val = READ_ONCE(sk->sk_priority);
1815 break;
1816
1817 case SO_LINGER:
1818 lv = sizeof(v.ling);
1819 v.ling.l_onoff = sock_flag(sk, SOCK_LINGER);
1820 v.ling.l_linger = READ_ONCE(sk->sk_lingertime) / HZ;
1821 break;
1822
1823 case SO_BSDCOMPAT:
1824 break;
1825
1826 case SO_TIMESTAMP_OLD:
1827 v.val = sock_flag(sk, SOCK_RCVTSTAMP) &&
1828 !sock_flag(sk, SOCK_TSTAMP_NEW) &&
1829 !sock_flag(sk, SOCK_RCVTSTAMPNS);
1830 break;
1831
1832 case SO_TIMESTAMPNS_OLD:
1833 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && !sock_flag(sk, SOCK_TSTAMP_NEW);
1834 break;
1835
1836 case SO_TIMESTAMP_NEW:
1837 v.val = sock_flag(sk, SOCK_RCVTSTAMP) && sock_flag(sk, SOCK_TSTAMP_NEW);
1838 break;
1839
1840 case SO_TIMESTAMPNS_NEW:
1841 v.val = sock_flag(sk, SOCK_RCVTSTAMPNS) && sock_flag(sk, SOCK_TSTAMP_NEW);
1842 break;
1843
1844 case SO_TIMESTAMPING_OLD:
1845 case SO_TIMESTAMPING_NEW:
1846 lv = sizeof(v.timestamping);
1847 /* For the later-added case SO_TIMESTAMPING_NEW: Be strict about only
1848 * returning the flags when they were set through the same option.
1849 * Don't change the beviour for the old case SO_TIMESTAMPING_OLD.
1850 */
1851 if (optname == SO_TIMESTAMPING_OLD || sock_flag(sk, SOCK_TSTAMP_NEW)) {
1852 v.timestamping.flags = READ_ONCE(sk->sk_tsflags);
1853 v.timestamping.bind_phc = READ_ONCE(sk->sk_bind_phc);
1854 }
1855 break;
1856
1857 case SO_RCVTIMEO_OLD:
1858 case SO_RCVTIMEO_NEW:
1859 lv = sock_get_timeout(READ_ONCE(sk->sk_rcvtimeo), &v,
1860 SO_RCVTIMEO_OLD == optname);
1861 break;
1862
1863 case SO_SNDTIMEO_OLD:
1864 case SO_SNDTIMEO_NEW:
1865 lv = sock_get_timeout(READ_ONCE(sk->sk_sndtimeo), &v,
1866 SO_SNDTIMEO_OLD == optname);
1867 break;
1868
1869 case SO_RCVLOWAT:
1870 v.val = READ_ONCE(sk->sk_rcvlowat);
1871 break;
1872
1873 case SO_SNDLOWAT:
1874 v.val = 1;
1875 break;
1876
1877 case SO_PASSCRED:
1878 if (!sk_may_scm_recv(sk))
1879 return -EOPNOTSUPP;
1880
1881 v.val = sk->sk_scm_credentials;
1882 break;
1883
1884 case SO_PASSPIDFD:
1885 if (!sk_is_unix(sk))
1886 return -EOPNOTSUPP;
1887
1888 v.val = sk->sk_scm_pidfd;
1889 break;
1890
1891 case SO_PASSRIGHTS:
1892 if (!sk_is_unix(sk))
1893 return -EOPNOTSUPP;
1894
1895 v.val = sk->sk_scm_rights;
1896 break;
1897
1898 case SO_PEERCRED:
1899 {
1900 struct ucred peercred;
1901 if (len > sizeof(peercred))
1902 len = sizeof(peercred);
1903
1904 spin_lock(&sk->sk_peer_lock);
1905 cred_to_ucred(sk->sk_peer_pid, sk->sk_peer_cred, &peercred);
1906 spin_unlock(&sk->sk_peer_lock);
1907
1908 if (copy_to_sockptr(optval, &peercred, len))
1909 return -EFAULT;
1910 goto lenout;
1911 }
1912
1913 case SO_PEERPIDFD:
1914 {
1915 struct pid *peer_pid;
1916 struct file *pidfd_file = NULL;
1917 unsigned int flags = 0;
1918 int pidfd;
1919
1920 if (len > sizeof(pidfd))
1921 len = sizeof(pidfd);
1922
1923 spin_lock(&sk->sk_peer_lock);
1924 peer_pid = get_pid(sk->sk_peer_pid);
1925 spin_unlock(&sk->sk_peer_lock);
1926
1927 if (!peer_pid)
1928 return -ENODATA;
1929
1930 /* The use of PIDFD_STALE requires stashing of struct pid
1931 * on pidfs with pidfs_register_pid() and only AF_UNIX
1932 * were prepared for this.
1933 */
1934 if (sk->sk_family == AF_UNIX)
1935 flags = PIDFD_STALE;
1936
1937 pidfd = pidfd_prepare(peer_pid, flags, &pidfd_file);
1938 put_pid(peer_pid);
1939 if (pidfd < 0)
1940 return pidfd;
1941
1942 if (copy_to_sockptr(optval, &pidfd, len) ||
1943 copy_to_sockptr(optlen, &len, sizeof(int))) {
1944 put_unused_fd(pidfd);
1945 fput(pidfd_file);
1946
1947 return -EFAULT;
1948 }
1949
1950 fd_install(pidfd, pidfd_file);
1951 return 0;
1952 }
1953
1954 case SO_PEERGROUPS:
1955 {
1956 const struct cred *cred;
1957 int ret, n;
1958
1959 cred = sk_get_peer_cred(sk);
1960 if (!cred)
1961 return -ENODATA;
1962
1963 n = cred->group_info->ngroups;
1964 if (len < n * sizeof(gid_t)) {
1965 len = n * sizeof(gid_t);
1966 put_cred(cred);
1967 return copy_to_sockptr(optlen, &len, sizeof(int)) ? -EFAULT : -ERANGE;
1968 }
1969 len = n * sizeof(gid_t);
1970
1971 ret = groups_to_user(optval, cred->group_info);
1972 put_cred(cred);
1973 if (ret)
1974 return ret;
1975 goto lenout;
1976 }
1977
1978 case SO_PEERNAME:
1979 {
1980 struct sockaddr_storage address;
1981
1982 lv = READ_ONCE(sock->ops)->getname(sock, (struct sockaddr *)&address, 2);
1983 if (lv < 0)
1984 return -ENOTCONN;
1985 if (lv < len)
1986 return -EINVAL;
1987 if (copy_to_sockptr(optval, &address, len))
1988 return -EFAULT;
1989 goto lenout;
1990 }
1991
1992 /* Dubious BSD thing... Probably nobody even uses it, but
1993 * the UNIX standard wants it for whatever reason... -DaveM
1994 */
1995 case SO_ACCEPTCONN:
1996 v.val = sk->sk_state == TCP_LISTEN;
1997 break;
1998
1999 case SO_PASSSEC:
2000 if (!IS_ENABLED(CONFIG_SECURITY_NETWORK) || !sk_may_scm_recv(sk))
2001 return -EOPNOTSUPP;
2002
2003 v.val = sk->sk_scm_security;
2004 break;
2005
2006 case SO_PEERSEC:
2007 return security_socket_getpeersec_stream(sock,
2008 optval, optlen, len);
2009
2010 case SO_MARK:
2011 v.val = READ_ONCE(sk->sk_mark);
2012 break;
2013
2014 case SO_RCVMARK:
2015 v.val = sock_flag(sk, SOCK_RCVMARK);
2016 break;
2017
2018 case SO_RCVPRIORITY:
2019 v.val = sock_flag(sk, SOCK_RCVPRIORITY);
2020 break;
2021
2022 case SO_RXQ_OVFL:
2023 v.val = sock_flag(sk, SOCK_RXQ_OVFL);
2024 break;
2025
2026 case SO_WIFI_STATUS:
2027 v.val = sock_flag(sk, SOCK_WIFI_STATUS);
2028 break;
2029
2030 case SO_PEEK_OFF:
2031 if (!READ_ONCE(sock->ops)->set_peek_off)
2032 return -EOPNOTSUPP;
2033
2034 v.val = READ_ONCE(sk->sk_peek_off);
2035 break;
2036 case SO_NOFCS:
2037 v.val = sock_flag(sk, SOCK_NOFCS);
2038 break;
2039
2040 case SO_BINDTODEVICE:
2041 return sock_getbindtodevice(sk, optval, optlen, len);
2042
2043 case SO_GET_FILTER:
2044 len = sk_get_filter(sk, optval, len);
2045 if (len < 0)
2046 return len;
2047
2048 goto lenout;
2049
2050 case SO_LOCK_FILTER:
2051 v.val = sock_flag(sk, SOCK_FILTER_LOCKED);
2052 break;
2053
2054 case SO_BPF_EXTENSIONS:
2055 v.val = bpf_tell_extensions();
2056 break;
2057
2058 case SO_SELECT_ERR_QUEUE:
2059 v.val = sock_flag(sk, SOCK_SELECT_ERR_QUEUE);
2060 break;
2061
2062 #ifdef CONFIG_NET_RX_BUSY_POLL
2063 case SO_BUSY_POLL:
2064 v.val = READ_ONCE(sk->sk_ll_usec);
2065 break;
2066 case SO_PREFER_BUSY_POLL:
2067 v.val = READ_ONCE(sk->sk_prefer_busy_poll);
2068 break;
2069 #endif
2070
2071 case SO_MAX_PACING_RATE:
2072 /* The READ_ONCE() pair with the WRITE_ONCE() in sk_setsockopt() */
2073 if (sizeof(v.ulval) != sizeof(v.val) && len >= sizeof(v.ulval)) {
2074 lv = sizeof(v.ulval);
2075 v.ulval = READ_ONCE(sk->sk_max_pacing_rate);
2076 } else {
2077 /* 32bit version */
2078 v.val = min_t(unsigned long, ~0U,
2079 READ_ONCE(sk->sk_max_pacing_rate));
2080 }
2081 break;
2082
2083 case SO_INCOMING_CPU:
2084 v.val = READ_ONCE(sk->sk_incoming_cpu);
2085 break;
2086
2087 case SO_MEMINFO:
2088 {
2089 u32 meminfo[SK_MEMINFO_VARS];
2090
2091 sk_get_meminfo(sk, meminfo);
2092
2093 len = min_t(unsigned int, len, sizeof(meminfo));
2094 if (copy_to_sockptr(optval, &meminfo, len))
2095 return -EFAULT;
2096
2097 goto lenout;
2098 }
2099
2100 #ifdef CONFIG_NET_RX_BUSY_POLL
2101 case SO_INCOMING_NAPI_ID:
2102 v.val = READ_ONCE(sk->sk_napi_id);
2103
2104 /* aggregate non-NAPI IDs down to 0 */
2105 if (!napi_id_valid(v.val))
2106 v.val = 0;
2107
2108 break;
2109 #endif
2110
2111 case SO_COOKIE:
2112 lv = sizeof(u64);
2113 if (len < lv)
2114 return -EINVAL;
2115 v.val64 = sock_gen_cookie(sk);
2116 break;
2117
2118 case SO_ZEROCOPY:
2119 v.val = sock_flag(sk, SOCK_ZEROCOPY);
2120 break;
2121
2122 case SO_TXTIME:
2123 lv = sizeof(v.txtime);
2124 v.txtime.clockid = sk->sk_clockid;
2125 v.txtime.flags |= sk->sk_txtime_deadline_mode ?
2126 SOF_TXTIME_DEADLINE_MODE : 0;
2127 v.txtime.flags |= sk->sk_txtime_report_errors ?
2128 SOF_TXTIME_REPORT_ERRORS : 0;
2129 break;
2130
2131 case SO_BINDTOIFINDEX:
2132 v.val = READ_ONCE(sk->sk_bound_dev_if);
2133 break;
2134
2135 case SO_NETNS_COOKIE:
2136 lv = sizeof(u64);
2137 if (len != lv)
2138 return -EINVAL;
2139 v.val64 = sock_net(sk)->net_cookie;
2140 break;
2141
2142 case SO_BUF_LOCK:
2143 v.val = sk->sk_userlocks & SOCK_BUF_LOCK_MASK;
2144 break;
2145
2146 case SO_RESERVE_MEM:
2147 v.val = READ_ONCE(sk->sk_reserved_mem);
2148 break;
2149
2150 case SO_TXREHASH:
2151 if (!sk_is_tcp(sk))
2152 return -EOPNOTSUPP;
2153
2154 /* Paired with WRITE_ONCE() in sk_setsockopt() */
2155 v.val = READ_ONCE(sk->sk_txrehash);
2156 break;
2157
2158 default:
2159 /* We implement the SO_SNDLOWAT etc to not be settable
2160 * (1003.1g 7).
2161 */
2162 return -ENOPROTOOPT;
2163 }
2164
2165 if (len > lv)
2166 len = lv;
2167 if (copy_to_sockptr(optval, &v, len))
2168 return -EFAULT;
2169 lenout:
2170 if (copy_to_sockptr(optlen, &len, sizeof(int)))
2171 return -EFAULT;
2172 return 0;
2173 }
2174
2175 /*
2176 * Initialize an sk_lock.
2177 *
2178 * (We also register the sk_lock with the lock validator.)
2179 */
sock_lock_init(struct sock * sk)2180 static inline void sock_lock_init(struct sock *sk)
2181 {
2182 sk_owner_clear(sk);
2183
2184 if (sk->sk_kern_sock)
2185 sock_lock_init_class_and_name(
2186 sk,
2187 af_family_kern_slock_key_strings[sk->sk_family],
2188 af_family_kern_slock_keys + sk->sk_family,
2189 af_family_kern_key_strings[sk->sk_family],
2190 af_family_kern_keys + sk->sk_family);
2191 else
2192 sock_lock_init_class_and_name(
2193 sk,
2194 af_family_slock_key_strings[sk->sk_family],
2195 af_family_slock_keys + sk->sk_family,
2196 af_family_key_strings[sk->sk_family],
2197 af_family_keys + sk->sk_family);
2198 }
2199
2200 /*
2201 * Copy all fields from osk to nsk but nsk->sk_refcnt must not change yet,
2202 * even temporarily, because of RCU lookups. sk_node should also be left as is.
2203 * We must not copy fields between sk_dontcopy_begin and sk_dontcopy_end
2204 */
sock_copy(struct sock * nsk,const struct sock * osk)2205 static void sock_copy(struct sock *nsk, const struct sock *osk)
2206 {
2207 const struct proto *prot = READ_ONCE(osk->sk_prot);
2208 #ifdef CONFIG_SECURITY_NETWORK
2209 void *sptr = nsk->sk_security;
2210 #endif
2211
2212 /* If we move sk_tx_queue_mapping out of the private section,
2213 * we must check if sk_tx_queue_clear() is called after
2214 * sock_copy() in sk_clone_lock().
2215 */
2216 BUILD_BUG_ON(offsetof(struct sock, sk_tx_queue_mapping) <
2217 offsetof(struct sock, sk_dontcopy_begin) ||
2218 offsetof(struct sock, sk_tx_queue_mapping) >=
2219 offsetof(struct sock, sk_dontcopy_end));
2220
2221 memcpy(nsk, osk, offsetof(struct sock, sk_dontcopy_begin));
2222
2223 unsafe_memcpy(&nsk->sk_dontcopy_end, &osk->sk_dontcopy_end,
2224 prot->obj_size - offsetof(struct sock, sk_dontcopy_end),
2225 /* alloc is larger than struct, see sk_prot_alloc() */);
2226
2227 #ifdef CONFIG_SECURITY_NETWORK
2228 nsk->sk_security = sptr;
2229 security_sk_clone(osk, nsk);
2230 #endif
2231 }
2232
sk_prot_alloc(struct proto * prot,gfp_t priority,int family)2233 static struct sock *sk_prot_alloc(struct proto *prot, gfp_t priority,
2234 int family)
2235 {
2236 struct sock *sk;
2237 struct kmem_cache *slab;
2238
2239 slab = prot->slab;
2240 if (slab != NULL) {
2241 sk = kmem_cache_alloc(slab, priority & ~__GFP_ZERO);
2242 if (!sk)
2243 return sk;
2244 if (want_init_on_alloc(priority))
2245 sk_prot_clear_nulls(sk, prot->obj_size);
2246 } else
2247 sk = kmalloc(prot->obj_size, priority);
2248
2249 if (sk != NULL) {
2250 if (security_sk_alloc(sk, family, priority))
2251 goto out_free;
2252
2253 if (!try_module_get(prot->owner))
2254 goto out_free_sec;
2255 }
2256
2257 return sk;
2258
2259 out_free_sec:
2260 security_sk_free(sk);
2261 out_free:
2262 if (slab != NULL)
2263 kmem_cache_free(slab, sk);
2264 else
2265 kfree(sk);
2266 return NULL;
2267 }
2268
sk_prot_free(struct proto * prot,struct sock * sk)2269 static void sk_prot_free(struct proto *prot, struct sock *sk)
2270 {
2271 struct kmem_cache *slab;
2272 struct module *owner;
2273
2274 owner = prot->owner;
2275 slab = prot->slab;
2276
2277 cgroup_sk_free(&sk->sk_cgrp_data);
2278 mem_cgroup_sk_free(sk);
2279 security_sk_free(sk);
2280
2281 sk_owner_put(sk);
2282
2283 if (slab != NULL)
2284 kmem_cache_free(slab, sk);
2285 else
2286 kfree(sk);
2287 module_put(owner);
2288 }
2289
2290 /**
2291 * sk_alloc - All socket objects are allocated here
2292 * @net: the applicable net namespace
2293 * @family: protocol family
2294 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2295 * @prot: struct proto associated with this new sock instance
2296 * @kern: is this to be a kernel socket?
2297 */
sk_alloc(struct net * net,int family,gfp_t priority,struct proto * prot,int kern)2298 struct sock *sk_alloc(struct net *net, int family, gfp_t priority,
2299 struct proto *prot, int kern)
2300 {
2301 struct sock *sk;
2302
2303 sk = sk_prot_alloc(prot, priority | __GFP_ZERO, family);
2304 if (sk) {
2305 sk->sk_family = family;
2306 /*
2307 * See comment in struct sock definition to understand
2308 * why we need sk_prot_creator -acme
2309 */
2310 sk->sk_prot = sk->sk_prot_creator = prot;
2311
2312 if (READ_ONCE(net->core.sysctl_bypass_prot_mem))
2313 sk->sk_bypass_prot_mem = 1;
2314
2315 sk->sk_kern_sock = kern;
2316 sock_lock_init(sk);
2317
2318 sk->sk_net_refcnt = kern ? 0 : 1;
2319 if (likely(sk->sk_net_refcnt)) {
2320 get_net_track(net, &sk->ns_tracker, priority);
2321 sock_inuse_add(net, 1);
2322 } else {
2323 net_passive_inc(net);
2324 __netns_tracker_alloc(net, &sk->ns_tracker,
2325 false, priority);
2326 }
2327
2328 sock_net_set(sk, net);
2329 refcount_set(&sk->sk_wmem_alloc, SK_WMEM_ALLOC_BIAS);
2330
2331 mem_cgroup_sk_alloc(sk);
2332 cgroup_sk_alloc(&sk->sk_cgrp_data);
2333 sock_update_classid(&sk->sk_cgrp_data);
2334 sock_update_netprioidx(&sk->sk_cgrp_data);
2335 sk_tx_queue_clear(sk);
2336 }
2337
2338 return sk;
2339 }
2340 EXPORT_SYMBOL(sk_alloc);
2341
2342 /* Sockets having SOCK_RCU_FREE will call this function after one RCU
2343 * grace period. This is the case for UDP sockets and TCP listeners.
2344 */
__sk_destruct(struct rcu_head * head)2345 static void __sk_destruct(struct rcu_head *head)
2346 {
2347 struct sock *sk = container_of(head, struct sock, sk_rcu);
2348 struct net *net = sock_net(sk);
2349 struct sk_filter *filter;
2350
2351 if (sk->sk_destruct)
2352 sk->sk_destruct(sk);
2353
2354 filter = rcu_dereference_check(sk->sk_filter,
2355 refcount_read(&sk->sk_wmem_alloc) == 0);
2356 if (filter) {
2357 sk_filter_uncharge(sk, filter);
2358 RCU_INIT_POINTER(sk->sk_filter, NULL);
2359 }
2360
2361 sock_disable_timestamp(sk, SK_FLAGS_TIMESTAMP);
2362
2363 #ifdef CONFIG_BPF_SYSCALL
2364 bpf_sk_storage_free(sk);
2365 #endif
2366
2367 if (atomic_read(&sk->sk_omem_alloc))
2368 pr_debug("%s: optmem leakage (%d bytes) detected\n",
2369 __func__, atomic_read(&sk->sk_omem_alloc));
2370
2371 if (sk->sk_frag.page) {
2372 put_page(sk->sk_frag.page);
2373 sk->sk_frag.page = NULL;
2374 }
2375
2376 /* We do not need to acquire sk->sk_peer_lock, we are the last user. */
2377 put_cred(sk->sk_peer_cred);
2378 put_pid(sk->sk_peer_pid);
2379
2380 if (likely(sk->sk_net_refcnt)) {
2381 put_net_track(net, &sk->ns_tracker);
2382 } else {
2383 __netns_tracker_free(net, &sk->ns_tracker, false);
2384 net_passive_dec(net);
2385 }
2386 sk_prot_free(sk->sk_prot_creator, sk);
2387 }
2388
sk_net_refcnt_upgrade(struct sock * sk)2389 void sk_net_refcnt_upgrade(struct sock *sk)
2390 {
2391 struct net *net = sock_net(sk);
2392
2393 WARN_ON_ONCE(sk->sk_net_refcnt);
2394 __netns_tracker_free(net, &sk->ns_tracker, false);
2395 net_passive_dec(net);
2396 sk->sk_net_refcnt = 1;
2397 get_net_track(net, &sk->ns_tracker, GFP_KERNEL);
2398 sock_inuse_add(net, 1);
2399 }
2400 EXPORT_SYMBOL_GPL(sk_net_refcnt_upgrade);
2401
sk_destruct(struct sock * sk)2402 void sk_destruct(struct sock *sk)
2403 {
2404 bool use_call_rcu = sock_flag(sk, SOCK_RCU_FREE);
2405
2406 if (rcu_access_pointer(sk->sk_reuseport_cb)) {
2407 reuseport_detach_sock(sk);
2408 use_call_rcu = true;
2409 }
2410
2411 if (use_call_rcu)
2412 call_rcu(&sk->sk_rcu, __sk_destruct);
2413 else
2414 __sk_destruct(&sk->sk_rcu);
2415 }
2416
__sk_free(struct sock * sk)2417 static void __sk_free(struct sock *sk)
2418 {
2419 if (likely(sk->sk_net_refcnt))
2420 sock_inuse_add(sock_net(sk), -1);
2421
2422 if (unlikely(sk->sk_net_refcnt && sock_diag_has_destroy_listeners(sk)))
2423 sock_diag_broadcast_destroy(sk);
2424 else
2425 sk_destruct(sk);
2426 }
2427
sk_free(struct sock * sk)2428 void sk_free(struct sock *sk)
2429 {
2430 /*
2431 * We subtract one from sk_wmem_alloc and can know if
2432 * some packets are still in some tx queue.
2433 * If not null, sock_wfree() will call __sk_free(sk) later
2434 */
2435 if (refcount_dec_and_test(&sk->sk_wmem_alloc))
2436 __sk_free(sk);
2437 }
2438 EXPORT_SYMBOL(sk_free);
2439
sk_init_common(struct sock * sk)2440 static void sk_init_common(struct sock *sk)
2441 {
2442 skb_queue_head_init(&sk->sk_receive_queue);
2443 skb_queue_head_init(&sk->sk_write_queue);
2444 skb_queue_head_init(&sk->sk_error_queue);
2445
2446 rwlock_init(&sk->sk_callback_lock);
2447 lockdep_set_class_and_name(&sk->sk_receive_queue.lock,
2448 af_rlock_keys + sk->sk_family,
2449 af_family_rlock_key_strings[sk->sk_family]);
2450 lockdep_set_class_and_name(&sk->sk_write_queue.lock,
2451 af_wlock_keys + sk->sk_family,
2452 af_family_wlock_key_strings[sk->sk_family]);
2453 lockdep_set_class_and_name(&sk->sk_error_queue.lock,
2454 af_elock_keys + sk->sk_family,
2455 af_family_elock_key_strings[sk->sk_family]);
2456 if (sk->sk_kern_sock)
2457 lockdep_set_class_and_name(&sk->sk_callback_lock,
2458 af_kern_callback_keys + sk->sk_family,
2459 af_family_kern_clock_key_strings[sk->sk_family]);
2460 else
2461 lockdep_set_class_and_name(&sk->sk_callback_lock,
2462 af_callback_keys + sk->sk_family,
2463 af_family_clock_key_strings[sk->sk_family]);
2464 }
2465
2466 /**
2467 * sk_clone - clone a socket
2468 * @sk: the socket to clone
2469 * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc)
2470 * @lock: if true, lock the cloned sk
2471 *
2472 * If @lock is true, the clone is locked by bh_lock_sock(), and
2473 * caller must unlock socket even in error path by bh_unlock_sock().
2474 */
sk_clone(const struct sock * sk,const gfp_t priority,bool lock)2475 struct sock *sk_clone(const struct sock *sk, const gfp_t priority,
2476 bool lock)
2477 {
2478 struct proto *prot = READ_ONCE(sk->sk_prot);
2479 struct sk_filter *filter;
2480 bool is_charged = true;
2481 struct sock *newsk;
2482
2483 newsk = sk_prot_alloc(prot, priority, sk->sk_family);
2484 if (!newsk)
2485 goto out;
2486
2487 sock_copy(newsk, sk);
2488
2489 newsk->sk_prot_creator = prot;
2490
2491 /* SANITY */
2492 if (likely(newsk->sk_net_refcnt)) {
2493 get_net_track(sock_net(newsk), &newsk->ns_tracker, priority);
2494 sock_inuse_add(sock_net(newsk), 1);
2495 } else {
2496 /* Kernel sockets are not elevating the struct net refcount.
2497 * Instead, use a tracker to more easily detect if a layer
2498 * is not properly dismantling its kernel sockets at netns
2499 * destroy time.
2500 */
2501 net_passive_inc(sock_net(newsk));
2502 __netns_tracker_alloc(sock_net(newsk), &newsk->ns_tracker,
2503 false, priority);
2504 }
2505
2506 sk_node_init(&newsk->sk_node);
2507 sock_lock_init(newsk);
2508
2509 if (lock)
2510 bh_lock_sock(newsk);
2511
2512 newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL;
2513 newsk->sk_backlog.len = 0;
2514
2515 atomic_set(&newsk->sk_rmem_alloc, 0);
2516
2517 refcount_set(&newsk->sk_wmem_alloc, SK_WMEM_ALLOC_BIAS);
2518
2519 atomic_set(&newsk->sk_omem_alloc, 0);
2520 sk_init_common(newsk);
2521
2522 newsk->sk_dst_cache = NULL;
2523 newsk->sk_dst_pending_confirm = 0;
2524 newsk->sk_wmem_queued = 0;
2525 newsk->sk_forward_alloc = 0;
2526 newsk->sk_reserved_mem = 0;
2527 DEBUG_NET_WARN_ON_ONCE(newsk->sk_drop_counters);
2528 sk_drops_reset(newsk);
2529 newsk->sk_send_head = NULL;
2530 newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK;
2531 atomic_set(&newsk->sk_zckey, 0);
2532
2533 sock_reset_flag(newsk, SOCK_DONE);
2534
2535 #ifdef CONFIG_MEMCG
2536 /* sk->sk_memcg will be populated at accept() time */
2537 newsk->sk_memcg = NULL;
2538 #endif
2539
2540 cgroup_sk_clone(&newsk->sk_cgrp_data);
2541
2542 rcu_read_lock();
2543 filter = rcu_dereference(sk->sk_filter);
2544 if (filter != NULL)
2545 /* though it's an empty new sock, the charging may fail
2546 * if sysctl_optmem_max was changed between creation of
2547 * original socket and cloning
2548 */
2549 is_charged = sk_filter_charge(newsk, filter);
2550 RCU_INIT_POINTER(newsk->sk_filter, filter);
2551 rcu_read_unlock();
2552
2553 if (unlikely(!is_charged || xfrm_sk_clone_policy(newsk, sk))) {
2554 /* We need to make sure that we don't uncharge the new
2555 * socket if we couldn't charge it in the first place
2556 * as otherwise we uncharge the parent's filter.
2557 */
2558 if (!is_charged)
2559 RCU_INIT_POINTER(newsk->sk_filter, NULL);
2560
2561 goto free;
2562 }
2563
2564 RCU_INIT_POINTER(newsk->sk_reuseport_cb, NULL);
2565
2566 if (bpf_sk_storage_clone(sk, newsk))
2567 goto free;
2568
2569 /* Clear sk_user_data if parent had the pointer tagged
2570 * as not suitable for copying when cloning.
2571 */
2572 if (sk_user_data_is_nocopy(newsk))
2573 newsk->sk_user_data = NULL;
2574
2575 newsk->sk_err = 0;
2576 newsk->sk_err_soft = 0;
2577 newsk->sk_priority = 0;
2578 newsk->sk_incoming_cpu = raw_smp_processor_id();
2579
2580 /* Before updating sk_refcnt, we must commit prior changes to memory
2581 * (Documentation/RCU/rculist_nulls.rst for details)
2582 */
2583 smp_wmb();
2584 refcount_set(&newsk->sk_refcnt, 2);
2585
2586 sk_set_socket(newsk, NULL);
2587 sk_tx_queue_clear(newsk);
2588 sk_rx_queue_clear(newsk);
2589 RCU_INIT_POINTER(newsk->sk_wq, NULL);
2590
2591 if (newsk->sk_prot->sockets_allocated)
2592 sk_sockets_allocated_inc(newsk);
2593
2594 if (sock_needs_netstamp(sk) && newsk->sk_flags & SK_FLAGS_TIMESTAMP)
2595 net_enable_timestamp();
2596 out:
2597 return newsk;
2598 free:
2599 /* It is still raw copy of parent, so invalidate
2600 * destructor and make plain sk_free()
2601 */
2602 newsk->sk_destruct = NULL;
2603 if (lock)
2604 bh_unlock_sock(newsk);
2605 sk_free(newsk);
2606 newsk = NULL;
2607 goto out;
2608 }
2609 EXPORT_SYMBOL_GPL(sk_clone);
2610
sk_dst_gso_max_size(struct sock * sk,const struct net_device * dev)2611 static u32 sk_dst_gso_max_size(struct sock *sk, const struct net_device *dev)
2612 {
2613 bool is_ipv6 = false;
2614 u32 max_size;
2615
2616 #if IS_ENABLED(CONFIG_IPV6)
2617 is_ipv6 = (sk->sk_family == AF_INET6 &&
2618 !ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr));
2619 #endif
2620 /* pairs with the WRITE_ONCE() in netif_set_gso(_ipv4)_max_size() */
2621 max_size = is_ipv6 ? READ_ONCE(dev->gso_max_size) :
2622 READ_ONCE(dev->gso_ipv4_max_size);
2623 if (max_size > GSO_LEGACY_MAX_SIZE && !sk_is_tcp(sk))
2624 max_size = GSO_LEGACY_MAX_SIZE;
2625
2626 return max_size - (MAX_TCP_HEADER + 1);
2627 }
2628
sk_setup_caps(struct sock * sk,struct dst_entry * dst)2629 void sk_setup_caps(struct sock *sk, struct dst_entry *dst)
2630 {
2631 const struct net_device *dev;
2632 u32 max_segs = 1;
2633
2634 rcu_read_lock();
2635 dev = dst_dev_rcu(dst);
2636 sk->sk_route_caps = dev->features;
2637 if (sk_is_tcp(sk)) {
2638 struct inet_connection_sock *icsk = inet_csk(sk);
2639
2640 sk->sk_route_caps |= NETIF_F_GSO;
2641 icsk->icsk_ack.dst_quick_ack = dst_metric(dst, RTAX_QUICKACK);
2642 }
2643 if (sk->sk_route_caps & NETIF_F_GSO)
2644 sk->sk_route_caps |= NETIF_F_GSO_SOFTWARE;
2645 if (unlikely(sk->sk_gso_disabled))
2646 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2647 if (sk_can_gso(sk)) {
2648 if (dst->header_len && !xfrm_dst_offload_ok(dst)) {
2649 sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
2650 } else {
2651 sk->sk_route_caps |= NETIF_F_SG | NETIF_F_HW_CSUM;
2652 sk->sk_gso_max_size = sk_dst_gso_max_size(sk, dev);
2653 /* pairs with the WRITE_ONCE() in netif_set_gso_max_segs() */
2654 max_segs = max_t(u32, READ_ONCE(dev->gso_max_segs), 1);
2655 }
2656 }
2657 sk->sk_gso_max_segs = max_segs;
2658 sk_dst_set(sk, dst);
2659 rcu_read_unlock();
2660 }
2661 EXPORT_SYMBOL_GPL(sk_setup_caps);
2662
2663 /*
2664 * Simple resource managers for sockets.
2665 */
2666
2667
2668 /*
2669 * Write buffer destructor automatically called from kfree_skb.
2670 */
sock_wfree(struct sk_buff * skb)2671 void sock_wfree(struct sk_buff *skb)
2672 {
2673 unsigned int len = skb->truesize;
2674 struct sock *sk = skb->sk;
2675 bool free;
2676 int old;
2677
2678 if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) {
2679 void (*sk_write_space)(struct sock *sk);
2680
2681 sk_write_space = READ_ONCE(sk->sk_write_space);
2682
2683 if (sock_flag(sk, SOCK_RCU_FREE) &&
2684 sk_write_space == sock_def_write_space) {
2685 rcu_read_lock();
2686 free = __refcount_sub_and_test(len, &sk->sk_wmem_alloc,
2687 &old);
2688 sock_def_write_space_wfree(sk, old - len);
2689 rcu_read_unlock();
2690 if (unlikely(free))
2691 __sk_free(sk);
2692 return;
2693 }
2694
2695 /*
2696 * Keep a reference on sk_wmem_alloc, this will be released
2697 * after sk_write_space() call
2698 */
2699 WARN_ON(refcount_sub_and_test(len - 1, &sk->sk_wmem_alloc));
2700 sk_write_space(sk);
2701 len = 1;
2702 }
2703 /*
2704 * if sk_wmem_alloc reaches 0, we must finish what sk_free()
2705 * could not do because of in-flight packets
2706 */
2707 if (refcount_sub_and_test(len, &sk->sk_wmem_alloc))
2708 __sk_free(sk);
2709 }
2710 EXPORT_SYMBOL(sock_wfree);
2711
2712 /* This variant of sock_wfree() is used by TCP,
2713 * since it sets SOCK_USE_WRITE_QUEUE.
2714 */
__sock_wfree(struct sk_buff * skb)2715 void __sock_wfree(struct sk_buff *skb)
2716 {
2717 struct sock *sk = skb->sk;
2718
2719 if (refcount_sub_and_test(skb->truesize, &sk->sk_wmem_alloc))
2720 __sk_free(sk);
2721 }
2722
skb_set_owner_w(struct sk_buff * skb,struct sock * sk)2723 void skb_set_owner_w(struct sk_buff *skb, struct sock *sk)
2724 {
2725 int old_wmem;
2726
2727 skb_orphan(skb);
2728 #ifdef CONFIG_INET
2729 if (unlikely(!sk_fullsock(sk)))
2730 return skb_set_owner_edemux(skb, sk);
2731 #endif
2732 skb->sk = sk;
2733 skb->destructor = sock_wfree;
2734 skb_set_hash_from_sk(skb, sk);
2735 /*
2736 * We used to take a refcount on sk, but following operation
2737 * is enough to guarantee sk_free() won't free this sock until
2738 * all in-flight packets are completed
2739 */
2740 __refcount_add(skb->truesize, &sk->sk_wmem_alloc, &old_wmem);
2741
2742 /* (old_wmem == SK_WMEM_ALLOC_BIAS) if no other TX packet for this socket
2743 * is in a host queue (qdisc, NIC queue).
2744 * Set skb->ooo_okay so that netdev_pick_tx() can choose a TX queue
2745 * based on XPS for better performance.
2746 * Otherwise clear ooo_okay to not risk Out Of Order delivery.
2747 */
2748 skb->ooo_okay = (old_wmem == SK_WMEM_ALLOC_BIAS);
2749 }
2750 EXPORT_SYMBOL(skb_set_owner_w);
2751
can_skb_orphan_partial(const struct sk_buff * skb)2752 static bool can_skb_orphan_partial(const struct sk_buff *skb)
2753 {
2754 /* Drivers depend on in-order delivery for crypto offload,
2755 * partial orphan breaks out-of-order-OK logic.
2756 */
2757 if (skb_is_decrypted(skb))
2758 return false;
2759
2760 return (skb->destructor == sock_wfree ||
2761 (IS_ENABLED(CONFIG_INET) && skb->destructor == tcp_wfree));
2762 }
2763
2764 /* This helper is used by netem, as it can hold packets in its
2765 * delay queue. We want to allow the owner socket to send more
2766 * packets, as if they were already TX completed by a typical driver.
2767 * But we also want to keep skb->sk set because some packet schedulers
2768 * rely on it (sch_fq for example).
2769 */
skb_orphan_partial(struct sk_buff * skb)2770 void skb_orphan_partial(struct sk_buff *skb)
2771 {
2772 if (skb_is_tcp_pure_ack(skb))
2773 return;
2774
2775 if (can_skb_orphan_partial(skb) && skb_set_owner_sk_safe(skb, skb->sk))
2776 return;
2777
2778 skb_orphan(skb);
2779 }
2780 EXPORT_SYMBOL(skb_orphan_partial);
2781
2782 /*
2783 * Read buffer destructor automatically called from kfree_skb.
2784 */
sock_rfree(struct sk_buff * skb)2785 void sock_rfree(struct sk_buff *skb)
2786 {
2787 struct sock *sk = skb->sk;
2788 unsigned int len = skb->truesize;
2789
2790 atomic_sub(len, &sk->sk_rmem_alloc);
2791 sk_mem_uncharge(sk, len);
2792 }
2793 EXPORT_SYMBOL(sock_rfree);
2794
2795 /*
2796 * Buffer destructor for skbs that are not used directly in read or write
2797 * path, e.g. for error handler skbs. Automatically called from kfree_skb.
2798 */
sock_efree(struct sk_buff * skb)2799 void sock_efree(struct sk_buff *skb)
2800 {
2801 sock_put(skb->sk);
2802 }
2803 EXPORT_SYMBOL(sock_efree);
2804
2805 /* Buffer destructor for prefetch/receive path where reference count may
2806 * not be held, e.g. for listen sockets.
2807 */
2808 #ifdef CONFIG_INET
sock_pfree(struct sk_buff * skb)2809 void sock_pfree(struct sk_buff *skb)
2810 {
2811 struct sock *sk = skb->sk;
2812
2813 if (!sk_is_refcounted(sk))
2814 return;
2815
2816 if (sk->sk_state == TCP_NEW_SYN_RECV && inet_reqsk(sk)->syncookie) {
2817 inet_reqsk(sk)->rsk_listener = NULL;
2818 reqsk_free(inet_reqsk(sk));
2819 return;
2820 }
2821
2822 sock_gen_put(sk);
2823 }
2824 EXPORT_SYMBOL(sock_pfree);
2825 #endif /* CONFIG_INET */
2826
2827 /*
2828 * Allocate a skb from the socket's send buffer.
2829 */
sock_wmalloc(struct sock * sk,unsigned long size,int force,gfp_t priority)2830 struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force,
2831 gfp_t priority)
2832 {
2833 if (force ||
2834 refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf)) {
2835 struct sk_buff *skb = alloc_skb(size, priority);
2836
2837 if (skb) {
2838 skb_set_owner_w(skb, sk);
2839 return skb;
2840 }
2841 }
2842 return NULL;
2843 }
2844 EXPORT_SYMBOL(sock_wmalloc);
2845
sock_ofree(struct sk_buff * skb)2846 static void sock_ofree(struct sk_buff *skb)
2847 {
2848 struct sock *sk = skb->sk;
2849
2850 atomic_sub(skb->truesize, &sk->sk_omem_alloc);
2851 }
2852
sock_omalloc(struct sock * sk,unsigned long size,gfp_t priority)2853 struct sk_buff *sock_omalloc(struct sock *sk, unsigned long size,
2854 gfp_t priority)
2855 {
2856 struct sk_buff *skb;
2857
2858 /* small safe race: SKB_TRUESIZE may differ from final skb->truesize */
2859 if (atomic_read(&sk->sk_omem_alloc) + SKB_TRUESIZE(size) >
2860 READ_ONCE(sock_net(sk)->core.sysctl_optmem_max))
2861 return NULL;
2862
2863 skb = alloc_skb(size, priority);
2864 if (!skb)
2865 return NULL;
2866
2867 atomic_add(skb->truesize, &sk->sk_omem_alloc);
2868 skb->sk = sk;
2869 skb->destructor = sock_ofree;
2870 return skb;
2871 }
2872
2873 /*
2874 * Allocate a memory block from the socket's option memory buffer.
2875 */
sock_kmalloc(struct sock * sk,int size,gfp_t priority)2876 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority)
2877 {
2878 int optmem_max = READ_ONCE(sock_net(sk)->core.sysctl_optmem_max);
2879
2880 if ((unsigned int)size <= optmem_max &&
2881 atomic_read(&sk->sk_omem_alloc) + size < optmem_max) {
2882 void *mem;
2883 /* First do the add, to avoid the race if kmalloc
2884 * might sleep.
2885 */
2886 atomic_add(size, &sk->sk_omem_alloc);
2887 mem = kmalloc(size, priority);
2888 if (mem)
2889 return mem;
2890 atomic_sub(size, &sk->sk_omem_alloc);
2891 }
2892 return NULL;
2893 }
2894 EXPORT_SYMBOL(sock_kmalloc);
2895
2896 /*
2897 * Duplicate the input "src" memory block using the socket's
2898 * option memory buffer.
2899 */
sock_kmemdup(struct sock * sk,const void * src,int size,gfp_t priority)2900 void *sock_kmemdup(struct sock *sk, const void *src,
2901 int size, gfp_t priority)
2902 {
2903 void *mem;
2904
2905 mem = sock_kmalloc(sk, size, priority);
2906 if (mem)
2907 memcpy(mem, src, size);
2908 return mem;
2909 }
2910 EXPORT_SYMBOL(sock_kmemdup);
2911
2912 /* Free an option memory block. Note, we actually want the inline
2913 * here as this allows gcc to detect the nullify and fold away the
2914 * condition entirely.
2915 */
__sock_kfree_s(struct sock * sk,void * mem,int size,const bool nullify)2916 static inline void __sock_kfree_s(struct sock *sk, void *mem, int size,
2917 const bool nullify)
2918 {
2919 if (WARN_ON_ONCE(!mem))
2920 return;
2921 if (nullify)
2922 kfree_sensitive(mem);
2923 else
2924 kfree(mem);
2925 atomic_sub(size, &sk->sk_omem_alloc);
2926 }
2927
sock_kfree_s(struct sock * sk,void * mem,int size)2928 void sock_kfree_s(struct sock *sk, void *mem, int size)
2929 {
2930 __sock_kfree_s(sk, mem, size, false);
2931 }
2932 EXPORT_SYMBOL(sock_kfree_s);
2933
sock_kzfree_s(struct sock * sk,void * mem,int size)2934 void sock_kzfree_s(struct sock *sk, void *mem, int size)
2935 {
2936 __sock_kfree_s(sk, mem, size, true);
2937 }
2938 EXPORT_SYMBOL(sock_kzfree_s);
2939
2940 /* It is almost wait_for_tcp_memory minus release_sock/lock_sock.
2941 I think, these locks should be removed for datagram sockets.
2942 */
sock_wait_for_wmem(struct sock * sk,long timeo)2943 static long sock_wait_for_wmem(struct sock *sk, long timeo)
2944 {
2945 DEFINE_WAIT(wait);
2946
2947 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2948 for (;;) {
2949 if (!timeo)
2950 break;
2951 if (signal_pending(current))
2952 break;
2953 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2954 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
2955 if (refcount_read(&sk->sk_wmem_alloc) < READ_ONCE(sk->sk_sndbuf))
2956 break;
2957 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2958 break;
2959 if (READ_ONCE(sk->sk_err))
2960 break;
2961 timeo = schedule_timeout(timeo);
2962 }
2963 finish_wait(sk_sleep(sk), &wait);
2964 return timeo;
2965 }
2966
2967
2968 /*
2969 * Generic send/receive buffer handlers
2970 */
2971
sock_alloc_send_pskb(struct sock * sk,unsigned long header_len,unsigned long data_len,int noblock,int * errcode,int max_page_order)2972 struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
2973 unsigned long data_len, int noblock,
2974 int *errcode, int max_page_order)
2975 {
2976 struct sk_buff *skb;
2977 long timeo;
2978 int err;
2979
2980 timeo = sock_sndtimeo(sk, noblock);
2981 for (;;) {
2982 err = sock_error(sk);
2983 if (err != 0)
2984 goto failure;
2985
2986 err = -EPIPE;
2987 if (READ_ONCE(sk->sk_shutdown) & SEND_SHUTDOWN)
2988 goto failure;
2989
2990 if (sk_wmem_alloc_get(sk) < READ_ONCE(sk->sk_sndbuf))
2991 break;
2992
2993 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
2994 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
2995 err = -EAGAIN;
2996 if (!timeo)
2997 goto failure;
2998 if (signal_pending(current))
2999 goto interrupted;
3000 timeo = sock_wait_for_wmem(sk, timeo);
3001 }
3002 skb = alloc_skb_with_frags(header_len, data_len, max_page_order,
3003 errcode, sk->sk_allocation);
3004 if (skb)
3005 skb_set_owner_w(skb, sk);
3006 return skb;
3007
3008 interrupted:
3009 err = sock_intr_errno(timeo);
3010 failure:
3011 *errcode = err;
3012 return NULL;
3013 }
3014 EXPORT_SYMBOL(sock_alloc_send_pskb);
3015
__sock_cmsg_send(struct sock * sk,struct cmsghdr * cmsg,struct sockcm_cookie * sockc)3016 int __sock_cmsg_send(struct sock *sk, struct cmsghdr *cmsg,
3017 struct sockcm_cookie *sockc)
3018 {
3019 u32 tsflags;
3020
3021 BUILD_BUG_ON(SOF_TIMESTAMPING_LAST == (1 << 31));
3022
3023 switch (cmsg->cmsg_type) {
3024 case SO_MARK:
3025 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_RAW) &&
3026 !ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
3027 return -EPERM;
3028 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3029 return -EINVAL;
3030 sockc->mark = *(u32 *)CMSG_DATA(cmsg);
3031 break;
3032 case SO_TIMESTAMPING_OLD:
3033 case SO_TIMESTAMPING_NEW:
3034 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3035 return -EINVAL;
3036
3037 tsflags = *(u32 *)CMSG_DATA(cmsg);
3038 if (tsflags & ~SOF_TIMESTAMPING_TX_RECORD_MASK)
3039 return -EINVAL;
3040
3041 sockc->tsflags &= ~SOF_TIMESTAMPING_TX_RECORD_MASK;
3042 sockc->tsflags |= tsflags;
3043 break;
3044 case SCM_TXTIME:
3045 if (!sock_flag(sk, SOCK_TXTIME))
3046 return -EINVAL;
3047 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u64)))
3048 return -EINVAL;
3049 sockc->transmit_time = get_unaligned((u64 *)CMSG_DATA(cmsg));
3050 break;
3051 case SCM_TS_OPT_ID:
3052 if (sk_is_tcp(sk))
3053 return -EINVAL;
3054 tsflags = READ_ONCE(sk->sk_tsflags);
3055 if (!(tsflags & SOF_TIMESTAMPING_OPT_ID))
3056 return -EINVAL;
3057 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3058 return -EINVAL;
3059 sockc->ts_opt_id = *(u32 *)CMSG_DATA(cmsg);
3060 sockc->tsflags |= SOCKCM_FLAG_TS_OPT_ID;
3061 break;
3062 /* SCM_RIGHTS and SCM_CREDENTIALS are semantically in SOL_UNIX. */
3063 case SCM_RIGHTS:
3064 case SCM_CREDENTIALS:
3065 break;
3066 case SO_PRIORITY:
3067 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3068 return -EINVAL;
3069 if (!sk_set_prio_allowed(sk, *(u32 *)CMSG_DATA(cmsg)))
3070 return -EPERM;
3071 sockc->priority = *(u32 *)CMSG_DATA(cmsg);
3072 break;
3073 case SCM_DEVMEM_DMABUF:
3074 if (cmsg->cmsg_len != CMSG_LEN(sizeof(u32)))
3075 return -EINVAL;
3076 sockc->dmabuf_id = *(u32 *)CMSG_DATA(cmsg);
3077 break;
3078 default:
3079 return -EINVAL;
3080 }
3081 return 0;
3082 }
3083 EXPORT_SYMBOL(__sock_cmsg_send);
3084
sock_cmsg_send(struct sock * sk,struct msghdr * msg,struct sockcm_cookie * sockc)3085 int sock_cmsg_send(struct sock *sk, struct msghdr *msg,
3086 struct sockcm_cookie *sockc)
3087 {
3088 struct cmsghdr *cmsg;
3089 int ret;
3090
3091 for_each_cmsghdr(cmsg, msg) {
3092 if (!CMSG_OK(msg, cmsg))
3093 return -EINVAL;
3094 if (cmsg->cmsg_level != SOL_SOCKET)
3095 continue;
3096 ret = __sock_cmsg_send(sk, cmsg, sockc);
3097 if (ret)
3098 return ret;
3099 }
3100 return 0;
3101 }
3102 EXPORT_SYMBOL(sock_cmsg_send);
3103
sk_enter_memory_pressure(struct sock * sk)3104 static void sk_enter_memory_pressure(struct sock *sk)
3105 {
3106 if (!sk->sk_prot->enter_memory_pressure)
3107 return;
3108
3109 sk->sk_prot->enter_memory_pressure(sk);
3110 }
3111
sk_leave_memory_pressure(struct sock * sk)3112 static void sk_leave_memory_pressure(struct sock *sk)
3113 {
3114 if (sk->sk_prot->leave_memory_pressure) {
3115 INDIRECT_CALL_INET_1(sk->sk_prot->leave_memory_pressure,
3116 tcp_leave_memory_pressure, sk);
3117 } else {
3118 unsigned long *memory_pressure = sk->sk_prot->memory_pressure;
3119
3120 if (memory_pressure && READ_ONCE(*memory_pressure))
3121 WRITE_ONCE(*memory_pressure, 0);
3122 }
3123 }
3124
3125 DEFINE_STATIC_KEY_FALSE(net_high_order_alloc_disable_key);
3126
3127 /**
3128 * skb_page_frag_refill - check that a page_frag contains enough room
3129 * @sz: minimum size of the fragment we want to get
3130 * @pfrag: pointer to page_frag
3131 * @gfp: priority for memory allocation
3132 *
3133 * Note: While this allocator tries to use high order pages, there is
3134 * no guarantee that allocations succeed. Therefore, @sz MUST be
3135 * less or equal than PAGE_SIZE.
3136 */
skb_page_frag_refill(unsigned int sz,struct page_frag * pfrag,gfp_t gfp)3137 bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t gfp)
3138 {
3139 if (pfrag->page) {
3140 if (page_ref_count(pfrag->page) == 1) {
3141 pfrag->offset = 0;
3142 return true;
3143 }
3144 if (pfrag->offset + sz <= pfrag->size)
3145 return true;
3146 put_page(pfrag->page);
3147 }
3148
3149 pfrag->offset = 0;
3150 if (SKB_FRAG_PAGE_ORDER &&
3151 !static_branch_unlikely(&net_high_order_alloc_disable_key)) {
3152 /* Avoid direct reclaim but allow kswapd to wake */
3153 pfrag->page = alloc_pages((gfp & ~__GFP_DIRECT_RECLAIM) |
3154 __GFP_COMP | __GFP_NOWARN |
3155 __GFP_NORETRY,
3156 SKB_FRAG_PAGE_ORDER);
3157 if (likely(pfrag->page)) {
3158 pfrag->size = PAGE_SIZE << SKB_FRAG_PAGE_ORDER;
3159 return true;
3160 }
3161 }
3162 pfrag->page = alloc_page(gfp);
3163 if (likely(pfrag->page)) {
3164 pfrag->size = PAGE_SIZE;
3165 return true;
3166 }
3167 return false;
3168 }
3169 EXPORT_SYMBOL(skb_page_frag_refill);
3170
sk_page_frag_refill(struct sock * sk,struct page_frag * pfrag)3171 bool sk_page_frag_refill(struct sock *sk, struct page_frag *pfrag)
3172 {
3173 if (likely(skb_page_frag_refill(32U, pfrag, sk->sk_allocation)))
3174 return true;
3175
3176 if (!sk->sk_bypass_prot_mem)
3177 sk_enter_memory_pressure(sk);
3178
3179 sk_stream_moderate_sndbuf(sk);
3180
3181 return false;
3182 }
3183 EXPORT_SYMBOL(sk_page_frag_refill);
3184
__lock_sock(struct sock * sk)3185 static void __lock_sock(struct sock *sk)
3186 __releases(&sk->sk_lock.slock)
3187 __acquires(&sk->sk_lock.slock)
3188 {
3189 DEFINE_WAIT(wait);
3190
3191 for (;;) {
3192 prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait,
3193 TASK_UNINTERRUPTIBLE);
3194 spin_unlock_bh(&sk->sk_lock.slock);
3195 schedule();
3196 spin_lock_bh(&sk->sk_lock.slock);
3197 if (!sock_owned_by_user(sk))
3198 break;
3199 }
3200 finish_wait(&sk->sk_lock.wq, &wait);
3201 }
3202
__release_sock(struct sock * sk)3203 void __release_sock(struct sock *sk)
3204 __releases(&sk->sk_lock.slock)
3205 __acquires(&sk->sk_lock.slock)
3206 {
3207 struct sk_buff *skb, *next;
3208 int nb = 0;
3209
3210 while ((skb = sk->sk_backlog.head) != NULL) {
3211 sk->sk_backlog.head = sk->sk_backlog.tail = NULL;
3212
3213 spin_unlock_bh(&sk->sk_lock.slock);
3214
3215 while (1) {
3216 next = skb->next;
3217 prefetch(next);
3218 DEBUG_NET_WARN_ON_ONCE(skb_dst_is_noref(skb));
3219 skb_mark_not_on_list(skb);
3220 sk_backlog_rcv(sk, skb);
3221
3222 skb = next;
3223 if (!skb)
3224 break;
3225
3226 if (!(++nb & 15))
3227 cond_resched();
3228 }
3229
3230 spin_lock_bh(&sk->sk_lock.slock);
3231 }
3232
3233 /*
3234 * Doing the zeroing here guarantee we can not loop forever
3235 * while a wild producer attempts to flood us.
3236 */
3237 sk->sk_backlog.len = 0;
3238 }
3239
__sk_flush_backlog(struct sock * sk)3240 void __sk_flush_backlog(struct sock *sk)
3241 {
3242 spin_lock_bh(&sk->sk_lock.slock);
3243 __release_sock(sk);
3244
3245 if (sk->sk_prot->release_cb)
3246 INDIRECT_CALL_INET_1(sk->sk_prot->release_cb,
3247 tcp_release_cb, sk);
3248
3249 spin_unlock_bh(&sk->sk_lock.slock);
3250 }
3251 EXPORT_SYMBOL_GPL(__sk_flush_backlog);
3252
3253 /**
3254 * sk_wait_data - wait for data to arrive at sk_receive_queue
3255 * @sk: sock to wait on
3256 * @timeo: for how long
3257 * @skb: last skb seen on sk_receive_queue
3258 *
3259 * Now socket state including sk->sk_err is changed only under lock,
3260 * hence we may omit checks after joining wait queue.
3261 * We check receive queue before schedule() only as optimization;
3262 * it is very likely that release_sock() added new data.
3263 */
sk_wait_data(struct sock * sk,long * timeo,const struct sk_buff * skb)3264 int sk_wait_data(struct sock *sk, long *timeo, const struct sk_buff *skb)
3265 {
3266 DEFINE_WAIT_FUNC(wait, woken_wake_function);
3267 int rc;
3268
3269 add_wait_queue(sk_sleep(sk), &wait);
3270 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3271 rc = sk_wait_event(sk, timeo, skb_peek_tail(&sk->sk_receive_queue) != skb, &wait);
3272 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
3273 remove_wait_queue(sk_sleep(sk), &wait);
3274 return rc;
3275 }
3276 EXPORT_SYMBOL(sk_wait_data);
3277
3278 /**
3279 * __sk_mem_raise_allocated - increase memory_allocated
3280 * @sk: socket
3281 * @size: memory size to allocate
3282 * @amt: pages to allocate
3283 * @kind: allocation type
3284 *
3285 * Similar to __sk_mem_schedule(), but does not update sk_forward_alloc.
3286 *
3287 * Unlike the globally shared limits among the sockets under same protocol,
3288 * consuming the budget of a memcg won't have direct effect on other ones.
3289 * So be optimistic about memcg's tolerance, and leave the callers to decide
3290 * whether or not to raise allocated through sk_under_memory_pressure() or
3291 * its variants.
3292 */
__sk_mem_raise_allocated(struct sock * sk,int size,int amt,int kind)3293 int __sk_mem_raise_allocated(struct sock *sk, int size, int amt, int kind)
3294 {
3295 bool memcg_enabled = false, charged = false;
3296 struct proto *prot = sk->sk_prot;
3297 long allocated = 0;
3298
3299 if (!sk->sk_bypass_prot_mem) {
3300 sk_memory_allocated_add(sk, amt);
3301 allocated = sk_memory_allocated(sk);
3302 }
3303
3304 if (mem_cgroup_sk_enabled(sk)) {
3305 memcg_enabled = true;
3306 charged = mem_cgroup_sk_charge(sk, amt, gfp_memcg_charge());
3307 if (!charged)
3308 goto suppress_allocation;
3309 }
3310
3311 if (!allocated)
3312 return 1;
3313
3314 /* Under limit. */
3315 if (allocated <= sk_prot_mem_limits(sk, 0)) {
3316 sk_leave_memory_pressure(sk);
3317 return 1;
3318 }
3319
3320 /* Under pressure. */
3321 if (allocated > sk_prot_mem_limits(sk, 1))
3322 sk_enter_memory_pressure(sk);
3323
3324 /* Over hard limit. */
3325 if (allocated > sk_prot_mem_limits(sk, 2))
3326 goto suppress_allocation;
3327
3328 /* Guarantee minimum buffer size under pressure (either global
3329 * or memcg) to make sure features described in RFC 7323 (TCP
3330 * Extensions for High Performance) work properly.
3331 *
3332 * This rule does NOT stand when exceeds global or memcg's hard
3333 * limit, or else a DoS attack can be taken place by spawning
3334 * lots of sockets whose usage are under minimum buffer size.
3335 */
3336 if (kind == SK_MEM_RECV) {
3337 if (atomic_read(&sk->sk_rmem_alloc) < sk_get_rmem0(sk, prot))
3338 return 1;
3339
3340 } else { /* SK_MEM_SEND */
3341 int wmem0 = sk_get_wmem0(sk, prot);
3342
3343 if (sk->sk_type == SOCK_STREAM) {
3344 if (sk->sk_wmem_queued < wmem0)
3345 return 1;
3346 } else if (refcount_read(&sk->sk_wmem_alloc) < wmem0) {
3347 return 1;
3348 }
3349 }
3350
3351 if (sk_has_memory_pressure(sk)) {
3352 u64 alloc;
3353
3354 /* The following 'average' heuristic is within the
3355 * scope of global accounting, so it only makes
3356 * sense for global memory pressure.
3357 */
3358 if (!sk_under_global_memory_pressure(sk))
3359 return 1;
3360
3361 /* Try to be fair among all the sockets under global
3362 * pressure by allowing the ones that below average
3363 * usage to raise.
3364 */
3365 alloc = sk_sockets_allocated_read_positive(sk);
3366 if (sk_prot_mem_limits(sk, 2) > alloc *
3367 sk_mem_pages(sk->sk_wmem_queued +
3368 atomic_read(&sk->sk_rmem_alloc) +
3369 sk->sk_forward_alloc))
3370 return 1;
3371 }
3372
3373 suppress_allocation:
3374
3375 if (kind == SK_MEM_SEND && sk->sk_type == SOCK_STREAM) {
3376 sk_stream_moderate_sndbuf(sk);
3377
3378 /* Fail only if socket is _under_ its sndbuf.
3379 * In this case we cannot block, so that we have to fail.
3380 */
3381 if (sk->sk_wmem_queued + size >= sk->sk_sndbuf) {
3382 /* Force charge with __GFP_NOFAIL */
3383 if (memcg_enabled && !charged)
3384 mem_cgroup_sk_charge(sk, amt,
3385 gfp_memcg_charge() | __GFP_NOFAIL);
3386 return 1;
3387 }
3388 }
3389
3390 trace_sock_exceed_buf_limit(sk, prot, allocated, kind);
3391
3392 if (allocated)
3393 sk_memory_allocated_sub(sk, amt);
3394
3395 if (charged)
3396 mem_cgroup_sk_uncharge(sk, amt);
3397
3398 return 0;
3399 }
3400
3401 /**
3402 * __sk_mem_schedule - increase sk_forward_alloc and memory_allocated
3403 * @sk: socket
3404 * @size: memory size to allocate
3405 * @kind: allocation type
3406 *
3407 * If kind is SK_MEM_SEND, it means wmem allocation. Otherwise it means
3408 * rmem allocation. This function assumes that protocols which have
3409 * memory_pressure use sk_wmem_queued as write buffer accounting.
3410 */
__sk_mem_schedule(struct sock * sk,int size,int kind)3411 int __sk_mem_schedule(struct sock *sk, int size, int kind)
3412 {
3413 int ret, amt = sk_mem_pages(size);
3414
3415 sk_forward_alloc_add(sk, amt << PAGE_SHIFT);
3416 ret = __sk_mem_raise_allocated(sk, size, amt, kind);
3417 if (!ret)
3418 sk_forward_alloc_add(sk, -(amt << PAGE_SHIFT));
3419 return ret;
3420 }
3421 EXPORT_SYMBOL(__sk_mem_schedule);
3422
3423 /**
3424 * __sk_mem_reduce_allocated - reclaim memory_allocated
3425 * @sk: socket
3426 * @amount: number of quanta
3427 *
3428 * Similar to __sk_mem_reclaim(), but does not update sk_forward_alloc
3429 */
__sk_mem_reduce_allocated(struct sock * sk,int amount)3430 void __sk_mem_reduce_allocated(struct sock *sk, int amount)
3431 {
3432 if (mem_cgroup_sk_enabled(sk))
3433 mem_cgroup_sk_uncharge(sk, amount);
3434
3435 if (sk->sk_bypass_prot_mem)
3436 return;
3437
3438 sk_memory_allocated_sub(sk, amount);
3439
3440 if (sk_under_global_memory_pressure(sk) &&
3441 (sk_memory_allocated(sk) < sk_prot_mem_limits(sk, 0)))
3442 sk_leave_memory_pressure(sk);
3443 }
3444
3445 /**
3446 * __sk_mem_reclaim - reclaim sk_forward_alloc and memory_allocated
3447 * @sk: socket
3448 * @amount: number of bytes (rounded down to a PAGE_SIZE multiple)
3449 */
__sk_mem_reclaim(struct sock * sk,int amount)3450 void __sk_mem_reclaim(struct sock *sk, int amount)
3451 {
3452 amount >>= PAGE_SHIFT;
3453 sk_forward_alloc_add(sk, -(amount << PAGE_SHIFT));
3454 __sk_mem_reduce_allocated(sk, amount);
3455 }
3456 EXPORT_SYMBOL(__sk_mem_reclaim);
3457
__sk_charge(struct sock * sk,gfp_t gfp)3458 void __sk_charge(struct sock *sk, gfp_t gfp)
3459 {
3460 int amt;
3461
3462 gfp |= __GFP_NOFAIL;
3463 if (mem_cgroup_from_sk(sk)) {
3464 /* The socket has not been accepted yet, no need
3465 * to look at newsk->sk_wmem_queued.
3466 */
3467 amt = sk_mem_pages(sk->sk_forward_alloc +
3468 atomic_read(&sk->sk_rmem_alloc));
3469 if (amt)
3470 mem_cgroup_sk_charge(sk, amt, gfp);
3471 }
3472
3473 kmem_cache_charge(sk, gfp);
3474 }
3475
sk_set_peek_off(struct sock * sk,int val)3476 int sk_set_peek_off(struct sock *sk, int val)
3477 {
3478 WRITE_ONCE(sk->sk_peek_off, val);
3479 return 0;
3480 }
3481 EXPORT_SYMBOL_GPL(sk_set_peek_off);
3482
3483 /*
3484 * Set of default routines for initialising struct proto_ops when
3485 * the protocol does not support a particular function. In certain
3486 * cases where it makes no sense for a protocol to have a "do nothing"
3487 * function, some default processing is provided.
3488 */
3489
sock_no_bind(struct socket * sock,struct sockaddr_unsized * saddr,int len)3490 int sock_no_bind(struct socket *sock, struct sockaddr_unsized *saddr, int len)
3491 {
3492 return -EOPNOTSUPP;
3493 }
3494 EXPORT_SYMBOL(sock_no_bind);
3495
sock_no_connect(struct socket * sock,struct sockaddr_unsized * saddr,int len,int flags)3496 int sock_no_connect(struct socket *sock, struct sockaddr_unsized *saddr,
3497 int len, int flags)
3498 {
3499 return -EOPNOTSUPP;
3500 }
3501 EXPORT_SYMBOL(sock_no_connect);
3502
sock_no_socketpair(struct socket * sock1,struct socket * sock2)3503 int sock_no_socketpair(struct socket *sock1, struct socket *sock2)
3504 {
3505 return -EOPNOTSUPP;
3506 }
3507 EXPORT_SYMBOL(sock_no_socketpair);
3508
sock_no_accept(struct socket * sock,struct socket * newsock,struct proto_accept_arg * arg)3509 int sock_no_accept(struct socket *sock, struct socket *newsock,
3510 struct proto_accept_arg *arg)
3511 {
3512 return -EOPNOTSUPP;
3513 }
3514 EXPORT_SYMBOL(sock_no_accept);
3515
sock_no_getname(struct socket * sock,struct sockaddr * saddr,int peer)3516 int sock_no_getname(struct socket *sock, struct sockaddr *saddr,
3517 int peer)
3518 {
3519 return -EOPNOTSUPP;
3520 }
3521 EXPORT_SYMBOL(sock_no_getname);
3522
sock_no_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)3523 int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
3524 {
3525 return -EOPNOTSUPP;
3526 }
3527 EXPORT_SYMBOL(sock_no_ioctl);
3528
sock_no_listen(struct socket * sock,int backlog)3529 int sock_no_listen(struct socket *sock, int backlog)
3530 {
3531 return -EOPNOTSUPP;
3532 }
3533 EXPORT_SYMBOL(sock_no_listen);
3534
sock_no_shutdown(struct socket * sock,int how)3535 int sock_no_shutdown(struct socket *sock, int how)
3536 {
3537 return -EOPNOTSUPP;
3538 }
3539 EXPORT_SYMBOL(sock_no_shutdown);
3540
sock_no_sendmsg(struct socket * sock,struct msghdr * m,size_t len)3541 int sock_no_sendmsg(struct socket *sock, struct msghdr *m, size_t len)
3542 {
3543 return -EOPNOTSUPP;
3544 }
3545 EXPORT_SYMBOL(sock_no_sendmsg);
3546
sock_no_sendmsg_locked(struct sock * sk,struct msghdr * m,size_t len)3547 int sock_no_sendmsg_locked(struct sock *sk, struct msghdr *m, size_t len)
3548 {
3549 return -EOPNOTSUPP;
3550 }
3551 EXPORT_SYMBOL(sock_no_sendmsg_locked);
3552
sock_no_recvmsg(struct socket * sock,struct msghdr * m,size_t len,int flags)3553 int sock_no_recvmsg(struct socket *sock, struct msghdr *m, size_t len,
3554 int flags)
3555 {
3556 return -EOPNOTSUPP;
3557 }
3558 EXPORT_SYMBOL(sock_no_recvmsg);
3559
sock_no_mmap(struct file * file,struct socket * sock,struct vm_area_struct * vma)3560 int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma)
3561 {
3562 /* Mirror missing mmap method error code */
3563 return -ENODEV;
3564 }
3565 EXPORT_SYMBOL(sock_no_mmap);
3566
3567 /*
3568 * When a file is received (via SCM_RIGHTS, etc), we must bump the
3569 * various sock-based usage counts.
3570 */
__receive_sock(struct file * file)3571 void __receive_sock(struct file *file)
3572 {
3573 struct socket *sock;
3574
3575 sock = sock_from_file(file);
3576 if (sock) {
3577 sock_update_netprioidx(&sock->sk->sk_cgrp_data);
3578 sock_update_classid(&sock->sk->sk_cgrp_data);
3579 }
3580 }
3581
3582 /*
3583 * Default Socket Callbacks
3584 */
3585
sock_def_wakeup(struct sock * sk)3586 static void sock_def_wakeup(struct sock *sk)
3587 {
3588 struct socket_wq *wq;
3589
3590 rcu_read_lock();
3591 wq = rcu_dereference(sk->sk_wq);
3592 if (skwq_has_sleeper(wq))
3593 wake_up_interruptible_all(&wq->wait);
3594 rcu_read_unlock();
3595 }
3596
sock_def_error_report(struct sock * sk)3597 static void sock_def_error_report(struct sock *sk)
3598 {
3599 struct socket_wq *wq;
3600
3601 rcu_read_lock();
3602 wq = rcu_dereference(sk->sk_wq);
3603 if (skwq_has_sleeper(wq))
3604 wake_up_interruptible_poll(&wq->wait, EPOLLERR);
3605 sk_wake_async_rcu(sk, SOCK_WAKE_IO, POLL_ERR);
3606 rcu_read_unlock();
3607 }
3608
sock_def_readable(struct sock * sk)3609 void sock_def_readable(struct sock *sk)
3610 {
3611 struct socket_wq *wq;
3612
3613 trace_sk_data_ready(sk);
3614
3615 rcu_read_lock();
3616 wq = rcu_dereference(sk->sk_wq);
3617 if (skwq_has_sleeper(wq))
3618 wake_up_interruptible_sync_poll(&wq->wait, EPOLLIN | EPOLLPRI |
3619 EPOLLRDNORM | EPOLLRDBAND);
3620 sk_wake_async_rcu(sk, SOCK_WAKE_WAITD, POLL_IN);
3621 rcu_read_unlock();
3622 }
3623
sock_def_write_space(struct sock * sk)3624 static void sock_def_write_space(struct sock *sk)
3625 {
3626 struct socket_wq *wq;
3627
3628 rcu_read_lock();
3629
3630 /* Do not wake up a writer until he can make "significant"
3631 * progress. --DaveM
3632 */
3633 if (sock_writeable(sk)) {
3634 wq = rcu_dereference(sk->sk_wq);
3635 if (skwq_has_sleeper(wq))
3636 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3637 EPOLLWRNORM | EPOLLWRBAND);
3638
3639 /* Should agree with poll, otherwise some programs break */
3640 sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3641 }
3642
3643 rcu_read_unlock();
3644 }
3645
3646 /* An optimised version of sock_def_write_space(), should only be called
3647 * for SOCK_RCU_FREE sockets under RCU read section and after putting
3648 * ->sk_wmem_alloc.
3649 */
sock_def_write_space_wfree(struct sock * sk,int wmem_alloc)3650 static void sock_def_write_space_wfree(struct sock *sk, int wmem_alloc)
3651 {
3652 /* Do not wake up a writer until he can make "significant"
3653 * progress. --DaveM
3654 */
3655 if (__sock_writeable(sk, wmem_alloc)) {
3656 struct socket_wq *wq = rcu_dereference(sk->sk_wq);
3657
3658 /* rely on refcount_sub from sock_wfree() */
3659 smp_mb__after_atomic();
3660 if (wq && waitqueue_active(&wq->wait))
3661 wake_up_interruptible_sync_poll(&wq->wait, EPOLLOUT |
3662 EPOLLWRNORM | EPOLLWRBAND);
3663
3664 /* Should agree with poll, otherwise some programs break */
3665 sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
3666 }
3667 }
3668
sock_def_destruct(struct sock * sk)3669 static void sock_def_destruct(struct sock *sk)
3670 {
3671 }
3672
sk_send_sigurg(struct sock * sk)3673 void sk_send_sigurg(struct sock *sk)
3674 {
3675 if (sk->sk_socket && sk->sk_socket->file)
3676 if (send_sigurg(sk->sk_socket->file))
3677 sk_wake_async(sk, SOCK_WAKE_URG, POLL_PRI);
3678 }
3679 EXPORT_SYMBOL(sk_send_sigurg);
3680
sk_reset_timer(struct sock * sk,struct timer_list * timer,unsigned long expires)3681 void sk_reset_timer(struct sock *sk, struct timer_list* timer,
3682 unsigned long expires)
3683 {
3684 if (!mod_timer(timer, expires))
3685 sock_hold(sk);
3686 }
3687 EXPORT_SYMBOL(sk_reset_timer);
3688
sk_stop_timer(struct sock * sk,struct timer_list * timer)3689 void sk_stop_timer(struct sock *sk, struct timer_list* timer)
3690 {
3691 if (timer_delete(timer))
3692 __sock_put(sk);
3693 }
3694 EXPORT_SYMBOL(sk_stop_timer);
3695
sk_stop_timer_sync(struct sock * sk,struct timer_list * timer)3696 void sk_stop_timer_sync(struct sock *sk, struct timer_list *timer)
3697 {
3698 if (timer_delete_sync(timer))
3699 __sock_put(sk);
3700 }
3701 EXPORT_SYMBOL(sk_stop_timer_sync);
3702
sock_init_data_uid(struct socket * sock,struct sock * sk,kuid_t uid)3703 void sock_init_data_uid(struct socket *sock, struct sock *sk, kuid_t uid)
3704 {
3705 sk_init_common(sk);
3706 sk->sk_send_head = NULL;
3707
3708 timer_setup(&sk->sk_timer, NULL, 0);
3709
3710 sk->sk_allocation = GFP_KERNEL;
3711 sk->sk_rcvbuf = READ_ONCE(sysctl_rmem_default);
3712 sk->sk_sndbuf = READ_ONCE(sysctl_wmem_default);
3713 sk->sk_state = TCP_CLOSE;
3714 sk->sk_use_task_frag = true;
3715 sk_set_socket(sk, sock);
3716
3717 sock_set_flag(sk, SOCK_ZAPPED);
3718
3719 if (sock) {
3720 sk->sk_type = sock->type;
3721 RCU_INIT_POINTER(sk->sk_wq, &sock->wq);
3722 sock->sk = sk;
3723 } else {
3724 RCU_INIT_POINTER(sk->sk_wq, NULL);
3725 }
3726 sk->sk_uid = uid;
3727
3728 sk->sk_state_change = sock_def_wakeup;
3729 sk->sk_data_ready = sock_def_readable;
3730 sk->sk_write_space = sock_def_write_space;
3731 sk->sk_error_report = sock_def_error_report;
3732 sk->sk_destruct = sock_def_destruct;
3733
3734 sk->sk_frag.page = NULL;
3735 sk->sk_frag.offset = 0;
3736 sk->sk_peek_off = -1;
3737
3738 sk->sk_peer_pid = NULL;
3739 sk->sk_peer_cred = NULL;
3740 spin_lock_init(&sk->sk_peer_lock);
3741
3742 sk->sk_write_pending = 0;
3743 sk->sk_rcvlowat = 1;
3744 sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
3745 sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
3746
3747 sk->sk_stamp = SK_DEFAULT_STAMP;
3748 #if BITS_PER_LONG==32
3749 seqlock_init(&sk->sk_stamp_seq);
3750 #endif
3751 atomic_set(&sk->sk_zckey, 0);
3752
3753 #ifdef CONFIG_NET_RX_BUSY_POLL
3754 sk->sk_napi_id = 0;
3755 sk->sk_ll_usec = READ_ONCE(sysctl_net_busy_read);
3756 #endif
3757
3758 sk->sk_max_pacing_rate = ~0UL;
3759 sk->sk_pacing_rate = ~0UL;
3760 WRITE_ONCE(sk->sk_pacing_shift, 10);
3761 sk->sk_incoming_cpu = -1;
3762
3763 sk_rx_queue_clear(sk);
3764 /*
3765 * Before updating sk_refcnt, we must commit prior changes to memory
3766 * (Documentation/RCU/rculist_nulls.rst for details)
3767 */
3768 smp_wmb();
3769 refcount_set(&sk->sk_refcnt, 1);
3770 sk_drops_reset(sk);
3771 }
3772 EXPORT_SYMBOL(sock_init_data_uid);
3773
sock_init_data(struct socket * sock,struct sock * sk)3774 void sock_init_data(struct socket *sock, struct sock *sk)
3775 {
3776 kuid_t uid = sock ?
3777 SOCK_INODE(sock)->i_uid :
3778 make_kuid(sock_net(sk)->user_ns, 0);
3779
3780 sock_init_data_uid(sock, sk, uid);
3781 }
3782 EXPORT_SYMBOL(sock_init_data);
3783
lock_sock_nested(struct sock * sk,int subclass)3784 void noinline lock_sock_nested(struct sock *sk, int subclass)
3785 {
3786 /* The sk_lock has mutex_lock() semantics here. */
3787 mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_);
3788
3789 might_sleep();
3790 #ifdef CONFIG_64BIT
3791 if (sizeof(struct slock_owned) == sizeof(long)) {
3792 socket_lock_t tmp = {
3793 .slock = __SPIN_LOCK_UNLOCKED(tmp.slock),
3794 .owned = 1,
3795 };
3796 socket_lock_t old = {
3797 .slock = __SPIN_LOCK_UNLOCKED(old.slock),
3798 .owned = 0,
3799 };
3800
3801 if (likely(try_cmpxchg(&sk->sk_lock.combined,
3802 &old.combined, tmp.combined)))
3803 return;
3804 }
3805 #endif
3806 spin_lock_bh(&sk->sk_lock.slock);
3807 if (unlikely(sock_owned_by_user_nocheck(sk)))
3808 __lock_sock(sk);
3809 sk->sk_lock.owned = 1;
3810 spin_unlock_bh(&sk->sk_lock.slock);
3811 }
3812 EXPORT_SYMBOL(lock_sock_nested);
3813
release_sock(struct sock * sk)3814 void release_sock(struct sock *sk)
3815 {
3816 spin_lock_bh(&sk->sk_lock.slock);
3817
3818 if (unlikely(sk->sk_backlog.tail))
3819 __release_sock(sk);
3820
3821 if (sk->sk_prot->release_cb) {
3822 if (!tcp_release_cb_cond(sk))
3823 sk->sk_prot->release_cb(sk);
3824 }
3825 sock_release_ownership(sk);
3826 if (unlikely(waitqueue_active(&sk->sk_lock.wq)))
3827 wake_up(&sk->sk_lock.wq);
3828
3829 spin_unlock_bh(&sk->sk_lock.slock);
3830 }
3831 EXPORT_SYMBOL(release_sock);
3832
__lock_sock_fast(struct sock * sk)3833 bool __lock_sock_fast(struct sock *sk) __acquires(&sk->sk_lock.slock)
3834 {
3835 might_sleep();
3836 spin_lock_bh(&sk->sk_lock.slock);
3837
3838 if (likely(!sock_owned_by_user_nocheck(sk))) {
3839 /*
3840 * Fast path return with bottom halves disabled and
3841 * sock::sk_lock.slock held.
3842 *
3843 * The 'mutex' is not contended and holding
3844 * sock::sk_lock.slock prevents all other lockers to
3845 * proceed so the corresponding unlock_sock_fast() can
3846 * avoid the slow path of release_sock() completely and
3847 * just release slock.
3848 *
3849 * From a semantical POV this is equivalent to 'acquiring'
3850 * the 'mutex', hence the corresponding lockdep
3851 * mutex_release() has to happen in the fast path of
3852 * unlock_sock_fast().
3853 */
3854 return false;
3855 }
3856
3857 __lock_sock(sk);
3858 sk->sk_lock.owned = 1;
3859 __acquire(&sk->sk_lock.slock);
3860 spin_unlock_bh(&sk->sk_lock.slock);
3861 return true;
3862 }
3863 EXPORT_SYMBOL(__lock_sock_fast);
3864
sock_gettstamp(struct socket * sock,void __user * userstamp,bool timeval,bool time32)3865 int sock_gettstamp(struct socket *sock, void __user *userstamp,
3866 bool timeval, bool time32)
3867 {
3868 struct sock *sk = sock->sk;
3869 struct timespec64 ts;
3870
3871 sock_enable_timestamp(sk, SOCK_TIMESTAMP);
3872 ts = ktime_to_timespec64(sock_read_timestamp(sk));
3873 if (ts.tv_sec == -1)
3874 return -ENOENT;
3875 if (ts.tv_sec == 0) {
3876 ktime_t kt = ktime_get_real();
3877 sock_write_timestamp(sk, kt);
3878 ts = ktime_to_timespec64(kt);
3879 }
3880
3881 if (timeval)
3882 ts.tv_nsec /= 1000;
3883
3884 #ifdef CONFIG_COMPAT_32BIT_TIME
3885 if (time32)
3886 return put_old_timespec32(&ts, userstamp);
3887 #endif
3888 #ifdef CONFIG_SPARC64
3889 /* beware of padding in sparc64 timeval */
3890 if (timeval && !in_compat_syscall()) {
3891 struct __kernel_old_timeval __user tv = {
3892 .tv_sec = ts.tv_sec,
3893 .tv_usec = ts.tv_nsec,
3894 };
3895 if (copy_to_user(userstamp, &tv, sizeof(tv)))
3896 return -EFAULT;
3897 return 0;
3898 }
3899 #endif
3900 return put_timespec64(&ts, userstamp);
3901 }
3902 EXPORT_SYMBOL(sock_gettstamp);
3903
sock_enable_timestamp(struct sock * sk,enum sock_flags flag)3904 void sock_enable_timestamp(struct sock *sk, enum sock_flags flag)
3905 {
3906 if (!sock_flag(sk, flag)) {
3907 unsigned long previous_flags = sk->sk_flags;
3908
3909 sock_set_flag(sk, flag);
3910 /*
3911 * we just set one of the two flags which require net
3912 * time stamping, but time stamping might have been on
3913 * already because of the other one
3914 */
3915 if (sock_needs_netstamp(sk) &&
3916 !(previous_flags & SK_FLAGS_TIMESTAMP))
3917 net_enable_timestamp();
3918 }
3919 }
3920
sock_recv_errqueue(struct sock * sk,struct msghdr * msg,int len,int level,int type)3921 int sock_recv_errqueue(struct sock *sk, struct msghdr *msg, int len,
3922 int level, int type)
3923 {
3924 struct sock_extended_err ee;
3925 struct sk_buff *skb;
3926 int copied, err;
3927
3928 err = -EAGAIN;
3929 skb = sock_dequeue_err_skb(sk);
3930 if (skb == NULL)
3931 goto out;
3932
3933 copied = skb->len;
3934 if (copied > len) {
3935 msg->msg_flags |= MSG_TRUNC;
3936 copied = len;
3937 }
3938 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3939 if (err)
3940 goto out_free_skb;
3941
3942 sock_recv_timestamp(msg, sk, skb);
3943
3944 /* We must use a bounce buffer for CONFIG_HARDENED_USERCOPY=y */
3945 ee = SKB_EXT_ERR(skb)->ee;
3946 put_cmsg(msg, level, type, sizeof(ee), &ee);
3947
3948 msg->msg_flags |= MSG_ERRQUEUE;
3949 err = copied;
3950
3951 out_free_skb:
3952 kfree_skb(skb);
3953 out:
3954 return err;
3955 }
3956 EXPORT_SYMBOL(sock_recv_errqueue);
3957
3958 /*
3959 * Get a socket option on an socket.
3960 *
3961 * FIX: POSIX 1003.1g is very ambiguous here. It states that
3962 * asynchronous errors should be reported by getsockopt. We assume
3963 * this means if you specify SO_ERROR (otherwise what is the point of it).
3964 */
sock_common_getsockopt(struct socket * sock,int level,int optname,char __user * optval,int __user * optlen)3965 int sock_common_getsockopt(struct socket *sock, int level, int optname,
3966 char __user *optval, int __user *optlen)
3967 {
3968 struct sock *sk = sock->sk;
3969
3970 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
3971 return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen);
3972 }
3973 EXPORT_SYMBOL(sock_common_getsockopt);
3974
sock_common_recvmsg(struct socket * sock,struct msghdr * msg,size_t size,int flags)3975 int sock_common_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
3976 int flags)
3977 {
3978 struct sock *sk = sock->sk;
3979
3980 return sk->sk_prot->recvmsg(sk, msg, size, flags);
3981 }
3982 EXPORT_SYMBOL(sock_common_recvmsg);
3983
3984 /*
3985 * Set socket options on an inet socket.
3986 */
sock_common_setsockopt(struct socket * sock,int level,int optname,sockptr_t optval,unsigned int optlen)3987 int sock_common_setsockopt(struct socket *sock, int level, int optname,
3988 sockptr_t optval, unsigned int optlen)
3989 {
3990 struct sock *sk = sock->sk;
3991
3992 /* IPV6_ADDRFORM can change sk->sk_prot under us. */
3993 return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen);
3994 }
3995 EXPORT_SYMBOL(sock_common_setsockopt);
3996
sk_common_release(struct sock * sk)3997 void sk_common_release(struct sock *sk)
3998 {
3999 if (sk->sk_prot->destroy)
4000 sk->sk_prot->destroy(sk);
4001
4002 /*
4003 * Observation: when sk_common_release is called, processes have
4004 * no access to socket. But net still has.
4005 * Step one, detach it from networking:
4006 *
4007 * A. Remove from hash tables.
4008 */
4009
4010 sk->sk_prot->unhash(sk);
4011
4012 /*
4013 * In this point socket cannot receive new packets, but it is possible
4014 * that some packets are in flight because some CPU runs receiver and
4015 * did hash table lookup before we unhashed socket. They will achieve
4016 * receive queue and will be purged by socket destructor.
4017 *
4018 * Also we still have packets pending on receive queue and probably,
4019 * our own packets waiting in device queues. sock_destroy will drain
4020 * receive queue, but transmitted packets will delay socket destruction
4021 * until the last reference will be released.
4022 */
4023
4024 sock_orphan(sk);
4025
4026 xfrm_sk_free_policy(sk);
4027
4028 sock_put(sk);
4029 }
4030 EXPORT_SYMBOL(sk_common_release);
4031
sk_get_meminfo(const struct sock * sk,u32 * mem)4032 void sk_get_meminfo(const struct sock *sk, u32 *mem)
4033 {
4034 memset(mem, 0, sizeof(*mem) * SK_MEMINFO_VARS);
4035
4036 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
4037 mem[SK_MEMINFO_RCVBUF] = READ_ONCE(sk->sk_rcvbuf);
4038 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
4039 mem[SK_MEMINFO_SNDBUF] = READ_ONCE(sk->sk_sndbuf);
4040 mem[SK_MEMINFO_FWD_ALLOC] = READ_ONCE(sk->sk_forward_alloc);
4041 mem[SK_MEMINFO_WMEM_QUEUED] = READ_ONCE(sk->sk_wmem_queued);
4042 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
4043 mem[SK_MEMINFO_BACKLOG] = READ_ONCE(sk->sk_backlog.len);
4044 mem[SK_MEMINFO_DROPS] = sk_drops_read(sk);
4045 }
4046
4047 #ifdef CONFIG_PROC_FS
4048 static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
4049
sock_prot_inuse_get(struct net * net,struct proto * prot)4050 int sock_prot_inuse_get(struct net *net, struct proto *prot)
4051 {
4052 int cpu, idx = prot->inuse_idx;
4053 int res = 0;
4054
4055 for_each_possible_cpu(cpu)
4056 res += per_cpu_ptr(net->core.prot_inuse, cpu)->val[idx];
4057
4058 return res >= 0 ? res : 0;
4059 }
4060 EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
4061
sock_inuse_get(struct net * net)4062 int sock_inuse_get(struct net *net)
4063 {
4064 int cpu, res = 0;
4065
4066 for_each_possible_cpu(cpu)
4067 res += per_cpu_ptr(net->core.prot_inuse, cpu)->all;
4068
4069 return res;
4070 }
4071
4072 EXPORT_SYMBOL_GPL(sock_inuse_get);
4073
sock_inuse_init_net(struct net * net)4074 static int __net_init sock_inuse_init_net(struct net *net)
4075 {
4076 net->core.prot_inuse = alloc_percpu(struct prot_inuse);
4077 if (net->core.prot_inuse == NULL)
4078 return -ENOMEM;
4079 return 0;
4080 }
4081
sock_inuse_exit_net(struct net * net)4082 static void __net_exit sock_inuse_exit_net(struct net *net)
4083 {
4084 free_percpu(net->core.prot_inuse);
4085 }
4086
4087 static struct pernet_operations net_inuse_ops = {
4088 .init = sock_inuse_init_net,
4089 .exit = sock_inuse_exit_net,
4090 };
4091
net_inuse_init(void)4092 static __init int net_inuse_init(void)
4093 {
4094 if (register_pernet_subsys(&net_inuse_ops))
4095 panic("Cannot initialize net inuse counters");
4096
4097 return 0;
4098 }
4099
4100 core_initcall(net_inuse_init);
4101
assign_proto_idx(struct proto * prot)4102 static int assign_proto_idx(struct proto *prot)
4103 {
4104 prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
4105
4106 if (unlikely(prot->inuse_idx == PROTO_INUSE_NR)) {
4107 pr_err("PROTO_INUSE_NR exhausted\n");
4108 return -ENOSPC;
4109 }
4110
4111 set_bit(prot->inuse_idx, proto_inuse_idx);
4112 return 0;
4113 }
4114
release_proto_idx(struct proto * prot)4115 static void release_proto_idx(struct proto *prot)
4116 {
4117 if (prot->inuse_idx != PROTO_INUSE_NR)
4118 clear_bit(prot->inuse_idx, proto_inuse_idx);
4119 }
4120 #else
assign_proto_idx(struct proto * prot)4121 static inline int assign_proto_idx(struct proto *prot)
4122 {
4123 return 0;
4124 }
4125
release_proto_idx(struct proto * prot)4126 static inline void release_proto_idx(struct proto *prot)
4127 {
4128 }
4129
4130 #endif
4131
tw_prot_cleanup(struct timewait_sock_ops * twsk_prot)4132 static void tw_prot_cleanup(struct timewait_sock_ops *twsk_prot)
4133 {
4134 if (!twsk_prot)
4135 return;
4136 kfree(twsk_prot->twsk_slab_name);
4137 twsk_prot->twsk_slab_name = NULL;
4138 kmem_cache_destroy(twsk_prot->twsk_slab);
4139 twsk_prot->twsk_slab = NULL;
4140 }
4141
tw_prot_init(const struct proto * prot)4142 static int tw_prot_init(const struct proto *prot)
4143 {
4144 struct timewait_sock_ops *twsk_prot = prot->twsk_prot;
4145
4146 if (!twsk_prot)
4147 return 0;
4148
4149 twsk_prot->twsk_slab_name = kasprintf(GFP_KERNEL, "tw_sock_%s",
4150 prot->name);
4151 if (!twsk_prot->twsk_slab_name)
4152 return -ENOMEM;
4153
4154 twsk_prot->twsk_slab =
4155 kmem_cache_create(twsk_prot->twsk_slab_name,
4156 twsk_prot->twsk_obj_size, 0,
4157 SLAB_ACCOUNT | prot->slab_flags,
4158 NULL);
4159 if (!twsk_prot->twsk_slab) {
4160 pr_crit("%s: Can't create timewait sock SLAB cache!\n",
4161 prot->name);
4162 return -ENOMEM;
4163 }
4164
4165 return 0;
4166 }
4167
req_prot_cleanup(struct request_sock_ops * rsk_prot)4168 static void req_prot_cleanup(struct request_sock_ops *rsk_prot)
4169 {
4170 if (!rsk_prot)
4171 return;
4172 kfree(rsk_prot->slab_name);
4173 rsk_prot->slab_name = NULL;
4174 kmem_cache_destroy(rsk_prot->slab);
4175 rsk_prot->slab = NULL;
4176 }
4177
req_prot_init(const struct proto * prot)4178 static int req_prot_init(const struct proto *prot)
4179 {
4180 struct request_sock_ops *rsk_prot = prot->rsk_prot;
4181
4182 if (!rsk_prot)
4183 return 0;
4184
4185 rsk_prot->slab_name = kasprintf(GFP_KERNEL, "request_sock_%s",
4186 prot->name);
4187 if (!rsk_prot->slab_name)
4188 return -ENOMEM;
4189
4190 rsk_prot->slab = kmem_cache_create(rsk_prot->slab_name,
4191 rsk_prot->obj_size, 0,
4192 SLAB_ACCOUNT | prot->slab_flags,
4193 NULL);
4194
4195 if (!rsk_prot->slab) {
4196 pr_crit("%s: Can't create request sock SLAB cache!\n",
4197 prot->name);
4198 return -ENOMEM;
4199 }
4200 return 0;
4201 }
4202
proto_register(struct proto * prot,int alloc_slab)4203 int proto_register(struct proto *prot, int alloc_slab)
4204 {
4205 int ret = -ENOBUFS;
4206
4207 if (prot->memory_allocated && !prot->sysctl_mem) {
4208 pr_err("%s: missing sysctl_mem\n", prot->name);
4209 return -EINVAL;
4210 }
4211 if (prot->memory_allocated && !prot->per_cpu_fw_alloc) {
4212 pr_err("%s: missing per_cpu_fw_alloc\n", prot->name);
4213 return -EINVAL;
4214 }
4215 if (alloc_slab) {
4216 struct kmem_cache_args args = {
4217 .useroffset = prot->useroffset,
4218 .usersize = prot->usersize,
4219 .freeptr_offset = prot->freeptr_offset,
4220 .use_freeptr_offset = !!prot->freeptr_offset,
4221 };
4222
4223 prot->slab = kmem_cache_create(prot->name, prot->obj_size,
4224 &args,
4225 SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT |
4226 prot->slab_flags);
4227 if (prot->slab == NULL) {
4228 pr_crit("%s: Can't create sock SLAB cache!\n",
4229 prot->name);
4230 goto out;
4231 }
4232
4233 if (req_prot_init(prot))
4234 goto out_free_request_sock_slab;
4235
4236 if (tw_prot_init(prot))
4237 goto out_free_timewait_sock_slab;
4238 }
4239
4240 mutex_lock(&proto_list_mutex);
4241 ret = assign_proto_idx(prot);
4242 if (ret) {
4243 mutex_unlock(&proto_list_mutex);
4244 goto out_free_timewait_sock_slab;
4245 }
4246 list_add(&prot->node, &proto_list);
4247 mutex_unlock(&proto_list_mutex);
4248 return ret;
4249
4250 out_free_timewait_sock_slab:
4251 if (alloc_slab)
4252 tw_prot_cleanup(prot->twsk_prot);
4253 out_free_request_sock_slab:
4254 if (alloc_slab) {
4255 req_prot_cleanup(prot->rsk_prot);
4256
4257 kmem_cache_destroy(prot->slab);
4258 prot->slab = NULL;
4259 }
4260 out:
4261 return ret;
4262 }
4263 EXPORT_SYMBOL(proto_register);
4264
proto_unregister(struct proto * prot)4265 void proto_unregister(struct proto *prot)
4266 {
4267 mutex_lock(&proto_list_mutex);
4268 release_proto_idx(prot);
4269 list_del(&prot->node);
4270 mutex_unlock(&proto_list_mutex);
4271
4272 kmem_cache_destroy(prot->slab);
4273 prot->slab = NULL;
4274
4275 req_prot_cleanup(prot->rsk_prot);
4276 tw_prot_cleanup(prot->twsk_prot);
4277 }
4278 EXPORT_SYMBOL(proto_unregister);
4279
sock_load_diag_module(int family,int protocol)4280 int sock_load_diag_module(int family, int protocol)
4281 {
4282 if (!protocol) {
4283 if (!sock_is_registered(family))
4284 return -ENOENT;
4285
4286 return request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
4287 NETLINK_SOCK_DIAG, family);
4288 }
4289
4290 #ifdef CONFIG_INET
4291 if (family == AF_INET &&
4292 protocol != IPPROTO_RAW &&
4293 protocol < MAX_INET_PROTOS &&
4294 !rcu_access_pointer(inet_protos[protocol]))
4295 return -ENOENT;
4296 #endif
4297
4298 return request_module("net-pf-%d-proto-%d-type-%d-%d", PF_NETLINK,
4299 NETLINK_SOCK_DIAG, family, protocol);
4300 }
4301 EXPORT_SYMBOL(sock_load_diag_module);
4302
4303 #ifdef CONFIG_PROC_FS
proto_seq_start(struct seq_file * seq,loff_t * pos)4304 static void *proto_seq_start(struct seq_file *seq, loff_t *pos)
4305 __acquires(proto_list_mutex)
4306 {
4307 mutex_lock(&proto_list_mutex);
4308 return seq_list_start_head(&proto_list, *pos);
4309 }
4310
proto_seq_next(struct seq_file * seq,void * v,loff_t * pos)4311 static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4312 {
4313 return seq_list_next(v, &proto_list, pos);
4314 }
4315
proto_seq_stop(struct seq_file * seq,void * v)4316 static void proto_seq_stop(struct seq_file *seq, void *v)
4317 __releases(proto_list_mutex)
4318 {
4319 mutex_unlock(&proto_list_mutex);
4320 }
4321
proto_method_implemented(const void * method)4322 static char proto_method_implemented(const void *method)
4323 {
4324 return method == NULL ? 'n' : 'y';
4325 }
sock_prot_memory_allocated(struct proto * proto)4326 static long sock_prot_memory_allocated(struct proto *proto)
4327 {
4328 return proto->memory_allocated != NULL ? proto_memory_allocated(proto) : -1L;
4329 }
4330
sock_prot_memory_pressure(struct proto * proto)4331 static const char *sock_prot_memory_pressure(struct proto *proto)
4332 {
4333 return proto->memory_pressure != NULL ?
4334 proto_memory_pressure(proto) ? "yes" : "no" : "NI";
4335 }
4336
proto_seq_printf(struct seq_file * seq,struct proto * proto)4337 static void proto_seq_printf(struct seq_file *seq, struct proto *proto)
4338 {
4339
4340 seq_printf(seq, "%-9s %4u %6d %6ld %-3s %6u %-3s %-10s "
4341 "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n",
4342 proto->name,
4343 proto->obj_size,
4344 sock_prot_inuse_get(seq_file_net(seq), proto),
4345 sock_prot_memory_allocated(proto),
4346 sock_prot_memory_pressure(proto),
4347 proto->max_header,
4348 proto->slab == NULL ? "no" : "yes",
4349 module_name(proto->owner),
4350 proto_method_implemented(proto->close),
4351 proto_method_implemented(proto->connect),
4352 proto_method_implemented(proto->disconnect),
4353 proto_method_implemented(proto->accept),
4354 proto_method_implemented(proto->ioctl),
4355 proto_method_implemented(proto->init),
4356 proto_method_implemented(proto->destroy),
4357 proto_method_implemented(proto->shutdown),
4358 proto_method_implemented(proto->setsockopt),
4359 proto_method_implemented(proto->getsockopt),
4360 proto_method_implemented(proto->sendmsg),
4361 proto_method_implemented(proto->recvmsg),
4362 proto_method_implemented(proto->bind),
4363 proto_method_implemented(proto->backlog_rcv),
4364 proto_method_implemented(proto->hash),
4365 proto_method_implemented(proto->unhash),
4366 proto_method_implemented(proto->get_port),
4367 proto_method_implemented(proto->enter_memory_pressure));
4368 }
4369
proto_seq_show(struct seq_file * seq,void * v)4370 static int proto_seq_show(struct seq_file *seq, void *v)
4371 {
4372 if (v == &proto_list)
4373 seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s",
4374 "protocol",
4375 "size",
4376 "sockets",
4377 "memory",
4378 "press",
4379 "maxhdr",
4380 "slab",
4381 "module",
4382 "cl co di ac io in de sh ss gs se re bi br ha uh gp em\n");
4383 else
4384 proto_seq_printf(seq, list_entry(v, struct proto, node));
4385 return 0;
4386 }
4387
4388 static const struct seq_operations proto_seq_ops = {
4389 .start = proto_seq_start,
4390 .next = proto_seq_next,
4391 .stop = proto_seq_stop,
4392 .show = proto_seq_show,
4393 };
4394
proto_init_net(struct net * net)4395 static __net_init int proto_init_net(struct net *net)
4396 {
4397 if (!proc_create_net("protocols", 0444, net->proc_net, &proto_seq_ops,
4398 sizeof(struct seq_net_private)))
4399 return -ENOMEM;
4400
4401 return 0;
4402 }
4403
proto_exit_net(struct net * net)4404 static __net_exit void proto_exit_net(struct net *net)
4405 {
4406 remove_proc_entry("protocols", net->proc_net);
4407 }
4408
4409
4410 static __net_initdata struct pernet_operations proto_net_ops = {
4411 .init = proto_init_net,
4412 .exit = proto_exit_net,
4413 };
4414
proto_init(void)4415 static int __init proto_init(void)
4416 {
4417 return register_pernet_subsys(&proto_net_ops);
4418 }
4419
4420 subsys_initcall(proto_init);
4421
4422 #endif /* PROC_FS */
4423
4424 #ifdef CONFIG_NET_RX_BUSY_POLL
sk_busy_loop_end(void * p,unsigned long start_time)4425 bool sk_busy_loop_end(void *p, unsigned long start_time)
4426 {
4427 struct sock *sk = p;
4428
4429 if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
4430 return true;
4431
4432 if (sk_is_udp(sk) &&
4433 !skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
4434 return true;
4435
4436 return sk_busy_loop_timeout(sk, start_time);
4437 }
4438 EXPORT_SYMBOL(sk_busy_loop_end);
4439 #endif /* CONFIG_NET_RX_BUSY_POLL */
4440
sock_bind_add(struct sock * sk,struct sockaddr_unsized * addr,int addr_len)4441 int sock_bind_add(struct sock *sk, struct sockaddr_unsized *addr, int addr_len)
4442 {
4443 if (!sk->sk_prot->bind_add)
4444 return -EOPNOTSUPP;
4445 return sk->sk_prot->bind_add(sk, addr, addr_len);
4446 }
4447 EXPORT_SYMBOL(sock_bind_add);
4448
4449 /* 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)4450 int sock_ioctl_inout(struct sock *sk, unsigned int cmd,
4451 void __user *arg, void *karg, size_t size)
4452 {
4453 int ret;
4454
4455 if (copy_from_user(karg, arg, size))
4456 return -EFAULT;
4457
4458 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, karg);
4459 if (ret)
4460 return ret;
4461
4462 if (copy_to_user(arg, karg, size))
4463 return -EFAULT;
4464
4465 return 0;
4466 }
4467 EXPORT_SYMBOL(sock_ioctl_inout);
4468
4469 /* This is the most common ioctl prep function, where the result (4 bytes) is
4470 * copied back to userspace if the ioctl() returns successfully. No input is
4471 * copied from userspace as input argument.
4472 */
sock_ioctl_out(struct sock * sk,unsigned int cmd,void __user * arg)4473 static int sock_ioctl_out(struct sock *sk, unsigned int cmd, void __user *arg)
4474 {
4475 int ret, karg = 0;
4476
4477 ret = READ_ONCE(sk->sk_prot)->ioctl(sk, cmd, &karg);
4478 if (ret)
4479 return ret;
4480
4481 return put_user(karg, (int __user *)arg);
4482 }
4483
4484 /* A wrapper around sock ioctls, which copies the data from userspace
4485 * (depending on the protocol/ioctl), and copies back the result to userspace.
4486 * The main motivation for this function is to pass kernel memory to the
4487 * protocol ioctl callbacks, instead of userspace memory.
4488 */
sk_ioctl(struct sock * sk,unsigned int cmd,void __user * arg)4489 int sk_ioctl(struct sock *sk, unsigned int cmd, void __user *arg)
4490 {
4491 int rc = 1;
4492
4493 if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET)
4494 rc = ipmr_sk_ioctl(sk, cmd, arg);
4495 else if (sk->sk_type == SOCK_RAW && sk->sk_family == AF_INET6)
4496 rc = ip6mr_sk_ioctl(sk, cmd, arg);
4497 else if (sk_is_phonet(sk))
4498 rc = phonet_sk_ioctl(sk, cmd, arg);
4499
4500 /* If ioctl was processed, returns its value */
4501 if (rc <= 0)
4502 return rc;
4503
4504 /* Otherwise call the default handler */
4505 return sock_ioctl_out(sk, cmd, arg);
4506 }
4507 EXPORT_SYMBOL(sk_ioctl);
4508
sock_struct_check(void)4509 static int __init sock_struct_check(void)
4510 {
4511 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_drops);
4512 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_peek_off);
4513 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_error_queue);
4514 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_receive_queue);
4515 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rx, sk_backlog);
4516
4517 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst);
4518 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_ifindex);
4519 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rx_dst_cookie);
4520 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvbuf);
4521 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_filter);
4522 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_wq);
4523 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_data_ready);
4524 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvtimeo);
4525 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rx, sk_rcvlowat);
4526
4527 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_err);
4528 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_socket);
4529 #ifdef CONFIG_MEMCG
4530 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_rxtx, sk_memcg);
4531 #endif
4532
4533 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_lock);
4534 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_reserved_mem);
4535 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_forward_alloc);
4536 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_rxtx, sk_tsflags);
4537
4538 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4539 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_omem_alloc);
4540 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_err_soft);
4541 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_queued);
4542 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_wmem_alloc);
4543 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tsq_flags);
4544 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_send_head);
4545 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_queue);
4546 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_write_pending);
4547 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_frag);
4548 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_timer);
4549 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_pacing_rate);
4550 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_zckey);
4551 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_write_tx, sk_tskey);
4552
4553 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_pending_confirm);
4554 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_status);
4555 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_max_pacing_rate);
4556 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndtimeo);
4557 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_priority);
4558 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_mark);
4559 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_uid);
4560 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_protocol);
4561 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_dst_cache);
4562 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_route_caps);
4563 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_type);
4564 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_size);
4565 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_allocation);
4566 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_txhash);
4567 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_sndbuf);
4568 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_gso_max_segs);
4569 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_pacing_shift);
4570 CACHELINE_ASSERT_GROUP_MEMBER(struct sock, sock_read_tx, sk_use_task_frag);
4571 return 0;
4572 }
4573
4574 core_initcall(sock_struct_check);
4575