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12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14#include <linux/module.h>
15#include <linux/net.h>
16#include <linux/skbuff.h>
17#include <linux/errqueue.h>
18#include <linux/udp.h>
19#include <linux/in.h>
20#include <linux/in6.h>
21#include <linux/icmp.h>
22#include <linux/gfp.h>
23#include <linux/circ_buf.h>
24#include <net/sock.h>
25#include <net/af_rxrpc.h>
26#include <net/ip.h>
27#include "ar-internal.h"
28
29
30
31
32
33static int rxrpc_service_prealloc_one(struct rxrpc_sock *rx,
34 struct rxrpc_backlog *b,
35 rxrpc_notify_rx_t notify_rx,
36 rxrpc_user_attach_call_t user_attach_call,
37 unsigned long user_call_ID, gfp_t gfp,
38 unsigned int debug_id)
39{
40 const void *here = __builtin_return_address(0);
41 struct rxrpc_call *call;
42 struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
43 int max, tmp;
44 unsigned int size = RXRPC_BACKLOG_MAX;
45 unsigned int head, tail, call_head, call_tail;
46
47 max = rx->sk.sk_max_ack_backlog;
48 tmp = rx->sk.sk_ack_backlog;
49 if (tmp >= max) {
50 _leave(" = -ENOBUFS [full %u]", max);
51 return -ENOBUFS;
52 }
53 max -= tmp;
54
55
56
57
58
59 call_head = b->call_backlog_head;
60 call_tail = READ_ONCE(b->call_backlog_tail);
61 tmp = CIRC_CNT(call_head, call_tail, size);
62 if (tmp >= max) {
63 _leave(" = -ENOBUFS [enough %u]", tmp);
64 return -ENOBUFS;
65 }
66 max = tmp + 1;
67
68 head = b->peer_backlog_head;
69 tail = READ_ONCE(b->peer_backlog_tail);
70 if (CIRC_CNT(head, tail, size) < max) {
71 struct rxrpc_peer *peer = rxrpc_alloc_peer(rx->local, gfp);
72 if (!peer)
73 return -ENOMEM;
74 b->peer_backlog[head] = peer;
75 smp_store_release(&b->peer_backlog_head,
76 (head + 1) & (size - 1));
77 }
78
79 head = b->conn_backlog_head;
80 tail = READ_ONCE(b->conn_backlog_tail);
81 if (CIRC_CNT(head, tail, size) < max) {
82 struct rxrpc_connection *conn;
83
84 conn = rxrpc_prealloc_service_connection(rxnet, gfp);
85 if (!conn)
86 return -ENOMEM;
87 b->conn_backlog[head] = conn;
88 smp_store_release(&b->conn_backlog_head,
89 (head + 1) & (size - 1));
90
91 trace_rxrpc_conn(conn, rxrpc_conn_new_service,
92 atomic_read(&conn->usage), here);
93 }
94
95
96
97
98 call = rxrpc_alloc_call(rx, gfp, debug_id);
99 if (!call)
100 return -ENOMEM;
101 call->flags |= (1 << RXRPC_CALL_IS_SERVICE);
102 call->state = RXRPC_CALL_SERVER_PREALLOC;
103
104 trace_rxrpc_call(call, rxrpc_call_new_service,
105 atomic_read(&call->usage),
106 here, (const void *)user_call_ID);
107
108 write_lock(&rx->call_lock);
109 if (user_attach_call) {
110 struct rxrpc_call *xcall;
111 struct rb_node *parent, **pp;
112
113
114 pp = &rx->calls.rb_node;
115 parent = NULL;
116 while (*pp) {
117 parent = *pp;
118 xcall = rb_entry(parent, struct rxrpc_call, sock_node);
119 if (user_call_ID < call->user_call_ID)
120 pp = &(*pp)->rb_left;
121 else if (user_call_ID > call->user_call_ID)
122 pp = &(*pp)->rb_right;
123 else
124 goto id_in_use;
125 }
126
127 call->user_call_ID = user_call_ID;
128 call->notify_rx = notify_rx;
129 rxrpc_get_call(call, rxrpc_call_got_kernel);
130 user_attach_call(call, user_call_ID);
131 rxrpc_get_call(call, rxrpc_call_got_userid);
132 rb_link_node(&call->sock_node, parent, pp);
133 rb_insert_color(&call->sock_node, &rx->calls);
134 set_bit(RXRPC_CALL_HAS_USERID, &call->flags);
135 }
136
137 list_add(&call->sock_link, &rx->sock_calls);
138
139 write_unlock(&rx->call_lock);
140
141 rxnet = call->rxnet;
142 write_lock(&rxnet->call_lock);
143 list_add_tail(&call->link, &rxnet->calls);
144 write_unlock(&rxnet->call_lock);
145
146 b->call_backlog[call_head] = call;
147 smp_store_release(&b->call_backlog_head, (call_head + 1) & (size - 1));
148 _leave(" = 0 [%d -> %lx]", call->debug_id, user_call_ID);
149 return 0;
150
151id_in_use:
152 write_unlock(&rx->call_lock);
153 rxrpc_cleanup_call(call);
154 _leave(" = -EBADSLT");
155 return -EBADSLT;
156}
157
158
159
160
161
162
163
164
165int rxrpc_service_prealloc(struct rxrpc_sock *rx, gfp_t gfp)
166{
167 struct rxrpc_backlog *b = rx->backlog;
168
169 if (!b) {
170 b = kzalloc(sizeof(struct rxrpc_backlog), gfp);
171 if (!b)
172 return -ENOMEM;
173 rx->backlog = b;
174 }
175
176 if (rx->discard_new_call)
177 return 0;
178
179 while (rxrpc_service_prealloc_one(rx, b, NULL, NULL, 0, gfp,
180 atomic_inc_return(&rxrpc_debug_id)) == 0)
181 ;
182
183 return 0;
184}
185
186
187
188
189void rxrpc_discard_prealloc(struct rxrpc_sock *rx)
190{
191 struct rxrpc_backlog *b = rx->backlog;
192 struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
193 unsigned int size = RXRPC_BACKLOG_MAX, head, tail;
194
195 if (!b)
196 return;
197 rx->backlog = NULL;
198
199
200
201
202 spin_lock_bh(&rx->incoming_lock);
203 spin_unlock_bh(&rx->incoming_lock);
204
205 head = b->peer_backlog_head;
206 tail = b->peer_backlog_tail;
207 while (CIRC_CNT(head, tail, size) > 0) {
208 struct rxrpc_peer *peer = b->peer_backlog[tail];
209 kfree(peer);
210 tail = (tail + 1) & (size - 1);
211 }
212
213 head = b->conn_backlog_head;
214 tail = b->conn_backlog_tail;
215 while (CIRC_CNT(head, tail, size) > 0) {
216 struct rxrpc_connection *conn = b->conn_backlog[tail];
217 write_lock(&rxnet->conn_lock);
218 list_del(&conn->link);
219 list_del(&conn->proc_link);
220 write_unlock(&rxnet->conn_lock);
221 kfree(conn);
222 if (atomic_dec_and_test(&rxnet->nr_conns))
223 wake_up_var(&rxnet->nr_conns);
224 tail = (tail + 1) & (size - 1);
225 }
226
227 head = b->call_backlog_head;
228 tail = b->call_backlog_tail;
229 while (CIRC_CNT(head, tail, size) > 0) {
230 struct rxrpc_call *call = b->call_backlog[tail];
231 rcu_assign_pointer(call->socket, rx);
232 if (rx->discard_new_call) {
233 _debug("discard %lx", call->user_call_ID);
234 rx->discard_new_call(call, call->user_call_ID);
235 rxrpc_put_call(call, rxrpc_call_put_kernel);
236 }
237 rxrpc_call_completed(call);
238 rxrpc_release_call(rx, call);
239 rxrpc_put_call(call, rxrpc_call_put);
240 tail = (tail + 1) & (size - 1);
241 }
242
243 kfree(b);
244}
245
246
247
248
249
250static struct rxrpc_call *rxrpc_alloc_incoming_call(struct rxrpc_sock *rx,
251 struct rxrpc_local *local,
252 struct rxrpc_connection *conn,
253 struct sk_buff *skb)
254{
255 struct rxrpc_backlog *b = rx->backlog;
256 struct rxrpc_peer *peer, *xpeer;
257 struct rxrpc_call *call;
258 unsigned short call_head, conn_head, peer_head;
259 unsigned short call_tail, conn_tail, peer_tail;
260 unsigned short call_count, conn_count;
261
262
263 call_head = smp_load_acquire(&b->call_backlog_head);
264 call_tail = b->call_backlog_tail;
265 call_count = CIRC_CNT(call_head, call_tail, RXRPC_BACKLOG_MAX);
266 conn_head = smp_load_acquire(&b->conn_backlog_head);
267 conn_tail = b->conn_backlog_tail;
268 conn_count = CIRC_CNT(conn_head, conn_tail, RXRPC_BACKLOG_MAX);
269 ASSERTCMP(conn_count, >=, call_count);
270 peer_head = smp_load_acquire(&b->peer_backlog_head);
271 peer_tail = b->peer_backlog_tail;
272 ASSERTCMP(CIRC_CNT(peer_head, peer_tail, RXRPC_BACKLOG_MAX), >=,
273 conn_count);
274
275 if (call_count == 0)
276 return NULL;
277
278 if (!conn) {
279
280
281
282
283
284 xpeer = b->peer_backlog[peer_tail];
285 if (rxrpc_extract_addr_from_skb(local, &xpeer->srx, skb) < 0)
286 return NULL;
287
288 peer = rxrpc_lookup_incoming_peer(local, xpeer);
289 if (peer == xpeer) {
290 b->peer_backlog[peer_tail] = NULL;
291 smp_store_release(&b->peer_backlog_tail,
292 (peer_tail + 1) &
293 (RXRPC_BACKLOG_MAX - 1));
294 }
295
296
297 conn = b->conn_backlog[conn_tail];
298 b->conn_backlog[conn_tail] = NULL;
299 smp_store_release(&b->conn_backlog_tail,
300 (conn_tail + 1) & (RXRPC_BACKLOG_MAX - 1));
301 conn->params.local = rxrpc_get_local(local);
302 conn->params.peer = peer;
303 rxrpc_see_connection(conn);
304 rxrpc_new_incoming_connection(rx, conn, skb);
305 } else {
306 rxrpc_get_connection(conn);
307 }
308
309
310 call = b->call_backlog[call_tail];
311 b->call_backlog[call_tail] = NULL;
312 smp_store_release(&b->call_backlog_tail,
313 (call_tail + 1) & (RXRPC_BACKLOG_MAX - 1));
314
315 rxrpc_see_call(call);
316 call->conn = conn;
317 call->peer = rxrpc_get_peer(conn->params.peer);
318 call->cong_cwnd = call->peer->cong_cwnd;
319 return call;
320}
321
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325
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329
330
331
332
333
334
335
336
337struct rxrpc_call *rxrpc_new_incoming_call(struct rxrpc_local *local,
338 struct rxrpc_connection *conn,
339 struct sk_buff *skb)
340{
341 struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
342 struct rxrpc_sock *rx;
343 struct rxrpc_call *call;
344 u16 service_id = sp->hdr.serviceId;
345
346 _enter("");
347
348
349 rx = rcu_dereference(local->service);
350 if (rx && (service_id == rx->srx.srx_service ||
351 service_id == rx->second_service))
352 goto found_service;
353
354 trace_rxrpc_abort(0, "INV", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
355 RX_INVALID_OPERATION, EOPNOTSUPP);
356 skb->mark = RXRPC_SKB_MARK_LOCAL_ABORT;
357 skb->priority = RX_INVALID_OPERATION;
358 _leave(" = NULL [service]");
359 return NULL;
360
361found_service:
362 spin_lock(&rx->incoming_lock);
363 if (rx->sk.sk_state == RXRPC_SERVER_LISTEN_DISABLED ||
364 rx->sk.sk_state == RXRPC_CLOSE) {
365 trace_rxrpc_abort(0, "CLS", sp->hdr.cid, sp->hdr.callNumber,
366 sp->hdr.seq, RX_INVALID_OPERATION, ESHUTDOWN);
367 skb->mark = RXRPC_SKB_MARK_LOCAL_ABORT;
368 skb->priority = RX_INVALID_OPERATION;
369 _leave(" = NULL [close]");
370 call = NULL;
371 goto out;
372 }
373
374 call = rxrpc_alloc_incoming_call(rx, local, conn, skb);
375 if (!call) {
376 skb->mark = RXRPC_SKB_MARK_BUSY;
377 _leave(" = NULL [busy]");
378 call = NULL;
379 goto out;
380 }
381
382 trace_rxrpc_receive(call, rxrpc_receive_incoming,
383 sp->hdr.serial, sp->hdr.seq);
384
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387
388
389
390
391
392
393
394 if (!mutex_trylock(&call->user_mutex))
395 BUG();
396
397
398 rxrpc_incoming_call(rx, call, skb);
399 conn = call->conn;
400
401 if (rx->notify_new_call)
402 rx->notify_new_call(&rx->sk, call, call->user_call_ID);
403 else
404 sk_acceptq_added(&rx->sk);
405
406 spin_lock(&conn->state_lock);
407 switch (conn->state) {
408 case RXRPC_CONN_SERVICE_UNSECURED:
409 conn->state = RXRPC_CONN_SERVICE_CHALLENGING;
410 set_bit(RXRPC_CONN_EV_CHALLENGE, &call->conn->events);
411 rxrpc_queue_conn(call->conn);
412 break;
413
414 case RXRPC_CONN_SERVICE:
415 write_lock(&call->state_lock);
416 if (rx->discard_new_call)
417 call->state = RXRPC_CALL_SERVER_RECV_REQUEST;
418 else
419 call->state = RXRPC_CALL_SERVER_ACCEPTING;
420 write_unlock(&call->state_lock);
421 break;
422
423 case RXRPC_CONN_REMOTELY_ABORTED:
424 rxrpc_set_call_completion(call, RXRPC_CALL_REMOTELY_ABORTED,
425 conn->remote_abort, -ECONNABORTED);
426 break;
427 case RXRPC_CONN_LOCALLY_ABORTED:
428 rxrpc_abort_call("CON", call, sp->hdr.seq,
429 conn->local_abort, -ECONNABORTED);
430 break;
431 default:
432 BUG();
433 }
434 spin_unlock(&conn->state_lock);
435
436 if (call->state == RXRPC_CALL_SERVER_ACCEPTING)
437 rxrpc_notify_socket(call);
438
439
440
441
442
443
444 rxrpc_put_call(call, rxrpc_call_put);
445
446 _leave(" = %p{%d}", call, call->debug_id);
447out:
448 spin_unlock(&rx->incoming_lock);
449 return call;
450}
451
452
453
454
455
456
457struct rxrpc_call *rxrpc_accept_call(struct rxrpc_sock *rx,
458 unsigned long user_call_ID,
459 rxrpc_notify_rx_t notify_rx)
460 __releases(&rx->sk.sk_lock.slock)
461 __acquires(call->user_mutex)
462{
463 struct rxrpc_call *call;
464 struct rb_node *parent, **pp;
465 int ret;
466
467 _enter(",%lx", user_call_ID);
468
469 ASSERT(!irqs_disabled());
470
471 write_lock(&rx->call_lock);
472
473 if (list_empty(&rx->to_be_accepted)) {
474 write_unlock(&rx->call_lock);
475 release_sock(&rx->sk);
476 kleave(" = -ENODATA [empty]");
477 return ERR_PTR(-ENODATA);
478 }
479
480
481 pp = &rx->calls.rb_node;
482 parent = NULL;
483 while (*pp) {
484 parent = *pp;
485 call = rb_entry(parent, struct rxrpc_call, sock_node);
486
487 if (user_call_ID < call->user_call_ID)
488 pp = &(*pp)->rb_left;
489 else if (user_call_ID > call->user_call_ID)
490 pp = &(*pp)->rb_right;
491 else
492 goto id_in_use;
493 }
494
495
496
497
498 call = list_entry(rx->to_be_accepted.next,
499 struct rxrpc_call, accept_link);
500 write_unlock(&rx->call_lock);
501
502
503
504
505
506
507 if (mutex_lock_interruptible(&call->user_mutex) < 0) {
508 release_sock(&rx->sk);
509 kleave(" = -ERESTARTSYS");
510 return ERR_PTR(-ERESTARTSYS);
511 }
512
513 write_lock(&rx->call_lock);
514 list_del_init(&call->accept_link);
515 sk_acceptq_removed(&rx->sk);
516 rxrpc_see_call(call);
517
518
519 pp = &rx->calls.rb_node;
520 parent = NULL;
521 while (*pp) {
522 parent = *pp;
523 call = rb_entry(parent, struct rxrpc_call, sock_node);
524
525 if (user_call_ID < call->user_call_ID)
526 pp = &(*pp)->rb_left;
527 else if (user_call_ID > call->user_call_ID)
528 pp = &(*pp)->rb_right;
529 else
530 BUG();
531 }
532
533 write_lock_bh(&call->state_lock);
534 switch (call->state) {
535 case RXRPC_CALL_SERVER_ACCEPTING:
536 call->state = RXRPC_CALL_SERVER_RECV_REQUEST;
537 break;
538 case RXRPC_CALL_COMPLETE:
539 ret = call->error;
540 goto out_release;
541 default:
542 BUG();
543 }
544
545
546 call->notify_rx = notify_rx;
547 call->user_call_ID = user_call_ID;
548 rxrpc_get_call(call, rxrpc_call_got_userid);
549 rb_link_node(&call->sock_node, parent, pp);
550 rb_insert_color(&call->sock_node, &rx->calls);
551 if (test_and_set_bit(RXRPC_CALL_HAS_USERID, &call->flags))
552 BUG();
553
554 write_unlock_bh(&call->state_lock);
555 write_unlock(&rx->call_lock);
556 rxrpc_notify_socket(call);
557 rxrpc_service_prealloc(rx, GFP_KERNEL);
558 release_sock(&rx->sk);
559 _leave(" = %p{%d}", call, call->debug_id);
560 return call;
561
562out_release:
563 _debug("release %p", call);
564 write_unlock_bh(&call->state_lock);
565 write_unlock(&rx->call_lock);
566 rxrpc_release_call(rx, call);
567 rxrpc_put_call(call, rxrpc_call_put);
568 goto out;
569
570id_in_use:
571 ret = -EBADSLT;
572 write_unlock(&rx->call_lock);
573out:
574 rxrpc_service_prealloc(rx, GFP_KERNEL);
575 release_sock(&rx->sk);
576 _leave(" = %d", ret);
577 return ERR_PTR(ret);
578}
579
580
581
582
583
584int rxrpc_reject_call(struct rxrpc_sock *rx)
585{
586 struct rxrpc_call *call;
587 bool abort = false;
588 int ret;
589
590 _enter("");
591
592 ASSERT(!irqs_disabled());
593
594 write_lock(&rx->call_lock);
595
596 if (list_empty(&rx->to_be_accepted)) {
597 write_unlock(&rx->call_lock);
598 return -ENODATA;
599 }
600
601
602
603
604 call = list_entry(rx->to_be_accepted.next,
605 struct rxrpc_call, accept_link);
606 list_del_init(&call->accept_link);
607 sk_acceptq_removed(&rx->sk);
608 rxrpc_see_call(call);
609
610 write_lock_bh(&call->state_lock);
611 switch (call->state) {
612 case RXRPC_CALL_SERVER_ACCEPTING:
613 __rxrpc_abort_call("REJ", call, 1, RX_USER_ABORT, -ECONNABORTED);
614 abort = true;
615
616 case RXRPC_CALL_COMPLETE:
617 ret = call->error;
618 goto out_discard;
619 default:
620 BUG();
621 }
622
623out_discard:
624 write_unlock_bh(&call->state_lock);
625 write_unlock(&rx->call_lock);
626 if (abort) {
627 rxrpc_send_abort_packet(call);
628 rxrpc_release_call(rx, call);
629 rxrpc_put_call(call, rxrpc_call_put);
630 }
631 rxrpc_service_prealloc(rx, GFP_KERNEL);
632 _leave(" = %d", ret);
633 return ret;
634}
635
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649
650
651int rxrpc_kernel_charge_accept(struct socket *sock,
652 rxrpc_notify_rx_t notify_rx,
653 rxrpc_user_attach_call_t user_attach_call,
654 unsigned long user_call_ID, gfp_t gfp,
655 unsigned int debug_id)
656{
657 struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
658 struct rxrpc_backlog *b = rx->backlog;
659
660 if (sock->sk->sk_state == RXRPC_CLOSE)
661 return -ESHUTDOWN;
662
663 return rxrpc_service_prealloc_one(rx, b, notify_rx,
664 user_attach_call, user_call_ID,
665 gfp, debug_id);
666}
667EXPORT_SYMBOL(rxrpc_kernel_charge_accept);
668