rxrpc: Add service upgrade support for client connections
[platform/kernel/linux-exynos.git] / net / rxrpc / sendmsg.c
1 /* AF_RXRPC sendmsg() implementation.
2  *
3  * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
4  * Written by David Howells (dhowells@redhat.com)
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public Licence
8  * as published by the Free Software Foundation; either version
9  * 2 of the Licence, or (at your option) any later version.
10  */
11
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14 #include <linux/net.h>
15 #include <linux/gfp.h>
16 #include <linux/skbuff.h>
17 #include <linux/export.h>
18 #include <linux/sched/signal.h>
19
20 #include <net/sock.h>
21 #include <net/af_rxrpc.h>
22 #include "ar-internal.h"
23
24 enum rxrpc_command {
25         RXRPC_CMD_SEND_DATA,            /* send data message */
26         RXRPC_CMD_SEND_ABORT,           /* request abort generation */
27         RXRPC_CMD_ACCEPT,               /* [server] accept incoming call */
28         RXRPC_CMD_REJECT_BUSY,          /* [server] reject a call as busy */
29 };
30
31 /*
32  * wait for space to appear in the transmit/ACK window
33  * - caller holds the socket locked
34  */
35 static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
36                                     struct rxrpc_call *call,
37                                     long *timeo)
38 {
39         DECLARE_WAITQUEUE(myself, current);
40         int ret;
41
42         _enter(",{%u,%u,%u}",
43                call->tx_hard_ack, call->tx_top, call->tx_winsize);
44
45         add_wait_queue(&call->waitq, &myself);
46
47         for (;;) {
48                 set_current_state(TASK_INTERRUPTIBLE);
49                 ret = 0;
50                 if (call->tx_top - call->tx_hard_ack <
51                     min_t(unsigned int, call->tx_winsize,
52                           call->cong_cwnd + call->cong_extra))
53                         break;
54                 if (call->state >= RXRPC_CALL_COMPLETE) {
55                         ret = -call->error;
56                         break;
57                 }
58                 if (signal_pending(current)) {
59                         ret = sock_intr_errno(*timeo);
60                         break;
61                 }
62
63                 trace_rxrpc_transmit(call, rxrpc_transmit_wait);
64                 mutex_unlock(&call->user_mutex);
65                 *timeo = schedule_timeout(*timeo);
66                 if (mutex_lock_interruptible(&call->user_mutex) < 0) {
67                         ret = sock_intr_errno(*timeo);
68                         break;
69                 }
70         }
71
72         remove_wait_queue(&call->waitq, &myself);
73         set_current_state(TASK_RUNNING);
74         _leave(" = %d", ret);
75         return ret;
76 }
77
78 /*
79  * Schedule an instant Tx resend.
80  */
81 static inline void rxrpc_instant_resend(struct rxrpc_call *call, int ix)
82 {
83         spin_lock_bh(&call->lock);
84
85         if (call->state < RXRPC_CALL_COMPLETE) {
86                 call->rxtx_annotations[ix] = RXRPC_TX_ANNO_RETRANS;
87                 if (!test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
88                         rxrpc_queue_call(call);
89         }
90
91         spin_unlock_bh(&call->lock);
92 }
93
94 /*
95  * Queue a DATA packet for transmission, set the resend timeout and send the
96  * packet immediately
97  */
98 static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
99                                bool last)
100 {
101         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
102         rxrpc_seq_t seq = sp->hdr.seq;
103         int ret, ix;
104         u8 annotation = RXRPC_TX_ANNO_UNACK;
105
106         _net("queue skb %p [%d]", skb, seq);
107
108         ASSERTCMP(seq, ==, call->tx_top + 1);
109
110         if (last)
111                 annotation |= RXRPC_TX_ANNO_LAST;
112
113         /* We have to set the timestamp before queueing as the retransmit
114          * algorithm can see the packet as soon as we queue it.
115          */
116         skb->tstamp = ktime_get_real();
117
118         ix = seq & RXRPC_RXTX_BUFF_MASK;
119         rxrpc_get_skb(skb, rxrpc_skb_tx_got);
120         call->rxtx_annotations[ix] = annotation;
121         smp_wmb();
122         call->rxtx_buffer[ix] = skb;
123         call->tx_top = seq;
124         if (last)
125                 trace_rxrpc_transmit(call, rxrpc_transmit_queue_last);
126         else
127                 trace_rxrpc_transmit(call, rxrpc_transmit_queue);
128
129         if (last || call->state == RXRPC_CALL_SERVER_ACK_REQUEST) {
130                 _debug("________awaiting reply/ACK__________");
131                 write_lock_bh(&call->state_lock);
132                 switch (call->state) {
133                 case RXRPC_CALL_CLIENT_SEND_REQUEST:
134                         call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
135                         break;
136                 case RXRPC_CALL_SERVER_ACK_REQUEST:
137                         call->state = RXRPC_CALL_SERVER_SEND_REPLY;
138                         call->ack_at = call->expire_at;
139                         if (call->ackr_reason == RXRPC_ACK_DELAY)
140                                 call->ackr_reason = 0;
141                         __rxrpc_set_timer(call, rxrpc_timer_init_for_send_reply,
142                                           ktime_get_real());
143                         if (!last)
144                                 break;
145                 case RXRPC_CALL_SERVER_SEND_REPLY:
146                         call->state = RXRPC_CALL_SERVER_AWAIT_ACK;
147                         break;
148                 default:
149                         break;
150                 }
151                 write_unlock_bh(&call->state_lock);
152         }
153
154         if (seq == 1 && rxrpc_is_client_call(call))
155                 rxrpc_expose_client_call(call);
156
157         ret = rxrpc_send_data_packet(call, skb, false);
158         if (ret < 0) {
159                 _debug("need instant resend %d", ret);
160                 rxrpc_instant_resend(call, ix);
161         } else {
162                 ktime_t now = ktime_get_real(), resend_at;
163
164                 resend_at = ktime_add_ms(now, rxrpc_resend_timeout);
165
166                 if (ktime_before(resend_at, call->resend_at)) {
167                         call->resend_at = resend_at;
168                         rxrpc_set_timer(call, rxrpc_timer_set_for_send, now);
169                 }
170         }
171
172         rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
173         _leave("");
174 }
175
176 /*
177  * send data through a socket
178  * - must be called in process context
179  * - The caller holds the call user access mutex, but not the socket lock.
180  */
181 static int rxrpc_send_data(struct rxrpc_sock *rx,
182                            struct rxrpc_call *call,
183                            struct msghdr *msg, size_t len)
184 {
185         struct rxrpc_skb_priv *sp;
186         struct sk_buff *skb;
187         struct sock *sk = &rx->sk;
188         long timeo;
189         bool more;
190         int ret, copied;
191
192         timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
193
194         /* this should be in poll */
195         sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
196
197         if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
198                 return -EPIPE;
199
200         more = msg->msg_flags & MSG_MORE;
201
202         skb = call->tx_pending;
203         call->tx_pending = NULL;
204         rxrpc_see_skb(skb, rxrpc_skb_tx_seen);
205
206         copied = 0;
207         do {
208                 /* Check to see if there's a ping ACK to reply to. */
209                 if (call->ackr_reason == RXRPC_ACK_PING_RESPONSE)
210                         rxrpc_send_ack_packet(call, false);
211
212                 if (!skb) {
213                         size_t size, chunk, max, space;
214
215                         _debug("alloc");
216
217                         if (call->tx_top - call->tx_hard_ack >=
218                             min_t(unsigned int, call->tx_winsize,
219                                   call->cong_cwnd + call->cong_extra)) {
220                                 ret = -EAGAIN;
221                                 if (msg->msg_flags & MSG_DONTWAIT)
222                                         goto maybe_error;
223                                 ret = rxrpc_wait_for_tx_window(rx, call,
224                                                                &timeo);
225                                 if (ret < 0)
226                                         goto maybe_error;
227                         }
228
229                         max = RXRPC_JUMBO_DATALEN;
230                         max -= call->conn->security_size;
231                         max &= ~(call->conn->size_align - 1UL);
232
233                         chunk = max;
234                         if (chunk > msg_data_left(msg) && !more)
235                                 chunk = msg_data_left(msg);
236
237                         space = chunk + call->conn->size_align;
238                         space &= ~(call->conn->size_align - 1UL);
239
240                         size = space + call->conn->security_size;
241
242                         _debug("SIZE: %zu/%zu/%zu", chunk, space, size);
243
244                         /* create a buffer that we can retain until it's ACK'd */
245                         skb = sock_alloc_send_skb(
246                                 sk, size, msg->msg_flags & MSG_DONTWAIT, &ret);
247                         if (!skb)
248                                 goto maybe_error;
249
250                         rxrpc_new_skb(skb, rxrpc_skb_tx_new);
251
252                         _debug("ALLOC SEND %p", skb);
253
254                         ASSERTCMP(skb->mark, ==, 0);
255
256                         _debug("HS: %u", call->conn->security_size);
257                         skb_reserve(skb, call->conn->security_size);
258                         skb->len += call->conn->security_size;
259
260                         sp = rxrpc_skb(skb);
261                         sp->remain = chunk;
262                         if (sp->remain > skb_tailroom(skb))
263                                 sp->remain = skb_tailroom(skb);
264
265                         _net("skb: hr %d, tr %d, hl %d, rm %d",
266                                skb_headroom(skb),
267                                skb_tailroom(skb),
268                                skb_headlen(skb),
269                                sp->remain);
270
271                         skb->ip_summed = CHECKSUM_UNNECESSARY;
272                 }
273
274                 _debug("append");
275                 sp = rxrpc_skb(skb);
276
277                 /* append next segment of data to the current buffer */
278                 if (msg_data_left(msg) > 0) {
279                         int copy = skb_tailroom(skb);
280                         ASSERTCMP(copy, >, 0);
281                         if (copy > msg_data_left(msg))
282                                 copy = msg_data_left(msg);
283                         if (copy > sp->remain)
284                                 copy = sp->remain;
285
286                         _debug("add");
287                         ret = skb_add_data(skb, &msg->msg_iter, copy);
288                         _debug("added");
289                         if (ret < 0)
290                                 goto efault;
291                         sp->remain -= copy;
292                         skb->mark += copy;
293                         copied += copy;
294                 }
295
296                 /* check for the far side aborting the call or a network error
297                  * occurring */
298                 if (call->state == RXRPC_CALL_COMPLETE)
299                         goto call_terminated;
300
301                 /* add the packet to the send queue if it's now full */
302                 if (sp->remain <= 0 ||
303                     (msg_data_left(msg) == 0 && !more)) {
304                         struct rxrpc_connection *conn = call->conn;
305                         uint32_t seq;
306                         size_t pad;
307
308                         /* pad out if we're using security */
309                         if (conn->security_ix) {
310                                 pad = conn->security_size + skb->mark;
311                                 pad = conn->size_align - pad;
312                                 pad &= conn->size_align - 1;
313                                 _debug("pad %zu", pad);
314                                 if (pad)
315                                         memset(skb_put(skb, pad), 0, pad);
316                         }
317
318                         seq = call->tx_top + 1;
319
320                         sp->hdr.seq     = seq;
321                         sp->hdr._rsvd   = 0;
322                         sp->hdr.flags   = conn->out_clientflag;
323
324                         if (msg_data_left(msg) == 0 && !more)
325                                 sp->hdr.flags |= RXRPC_LAST_PACKET;
326                         else if (call->tx_top - call->tx_hard_ack <
327                                  call->tx_winsize)
328                                 sp->hdr.flags |= RXRPC_MORE_PACKETS;
329
330                         ret = conn->security->secure_packet(
331                                 call, skb, skb->mark, skb->head);
332                         if (ret < 0)
333                                 goto out;
334
335                         rxrpc_queue_packet(call, skb, !msg_data_left(msg) && !more);
336                         skb = NULL;
337                 }
338         } while (msg_data_left(msg) > 0);
339
340 success:
341         ret = copied;
342 out:
343         call->tx_pending = skb;
344         _leave(" = %d", ret);
345         return ret;
346
347 call_terminated:
348         rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
349         _leave(" = %d", -call->error);
350         return -call->error;
351
352 maybe_error:
353         if (copied)
354                 goto success;
355         goto out;
356
357 efault:
358         ret = -EFAULT;
359         goto out;
360 }
361
362 /*
363  * extract control messages from the sendmsg() control buffer
364  */
365 static int rxrpc_sendmsg_cmsg(struct msghdr *msg,
366                               unsigned long *user_call_ID,
367                               enum rxrpc_command *command,
368                               u32 *abort_code,
369                               bool *_exclusive,
370                               bool *_upgrade)
371 {
372         struct cmsghdr *cmsg;
373         bool got_user_ID = false;
374         int len;
375
376         *command = RXRPC_CMD_SEND_DATA;
377
378         if (msg->msg_controllen == 0)
379                 return -EINVAL;
380
381         for_each_cmsghdr(cmsg, msg) {
382                 if (!CMSG_OK(msg, cmsg))
383                         return -EINVAL;
384
385                 len = cmsg->cmsg_len - sizeof(struct cmsghdr);
386                 _debug("CMSG %d, %d, %d",
387                        cmsg->cmsg_level, cmsg->cmsg_type, len);
388
389                 if (cmsg->cmsg_level != SOL_RXRPC)
390                         continue;
391
392                 switch (cmsg->cmsg_type) {
393                 case RXRPC_USER_CALL_ID:
394                         if (msg->msg_flags & MSG_CMSG_COMPAT) {
395                                 if (len != sizeof(u32))
396                                         return -EINVAL;
397                                 *user_call_ID = *(u32 *) CMSG_DATA(cmsg);
398                         } else {
399                                 if (len != sizeof(unsigned long))
400                                         return -EINVAL;
401                                 *user_call_ID = *(unsigned long *)
402                                         CMSG_DATA(cmsg);
403                         }
404                         _debug("User Call ID %lx", *user_call_ID);
405                         got_user_ID = true;
406                         break;
407
408                 case RXRPC_ABORT:
409                         if (*command != RXRPC_CMD_SEND_DATA)
410                                 return -EINVAL;
411                         *command = RXRPC_CMD_SEND_ABORT;
412                         if (len != sizeof(*abort_code))
413                                 return -EINVAL;
414                         *abort_code = *(unsigned int *) CMSG_DATA(cmsg);
415                         _debug("Abort %x", *abort_code);
416                         if (*abort_code == 0)
417                                 return -EINVAL;
418                         break;
419
420                 case RXRPC_ACCEPT:
421                         if (*command != RXRPC_CMD_SEND_DATA)
422                                 return -EINVAL;
423                         *command = RXRPC_CMD_ACCEPT;
424                         if (len != 0)
425                                 return -EINVAL;
426                         break;
427
428                 case RXRPC_EXCLUSIVE_CALL:
429                         *_exclusive = true;
430                         if (len != 0)
431                                 return -EINVAL;
432                         break;
433
434                 case RXRPC_UPGRADE_SERVICE:
435                         *_upgrade = true;
436                         if (len != 0)
437                                 return -EINVAL;
438                         break;
439
440                 default:
441                         return -EINVAL;
442                 }
443         }
444
445         if (!got_user_ID)
446                 return -EINVAL;
447         _leave(" = 0");
448         return 0;
449 }
450
451 /*
452  * Create a new client call for sendmsg().
453  * - Called with the socket lock held, which it must release.
454  * - If it returns a call, the call's lock will need releasing by the caller.
455  */
456 static struct rxrpc_call *
457 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
458                                   unsigned long user_call_ID, bool exclusive,
459                                   bool upgrade)
460         __releases(&rx->sk.sk_lock.slock)
461 {
462         struct rxrpc_conn_parameters cp;
463         struct rxrpc_call *call;
464         struct key *key;
465
466         DECLARE_SOCKADDR(struct sockaddr_rxrpc *, srx, msg->msg_name);
467
468         _enter("");
469
470         if (!msg->msg_name) {
471                 release_sock(&rx->sk);
472                 return ERR_PTR(-EDESTADDRREQ);
473         }
474
475         key = rx->key;
476         if (key && !rx->key->payload.data[0])
477                 key = NULL;
478
479         memset(&cp, 0, sizeof(cp));
480         cp.local                = rx->local;
481         cp.key                  = rx->key;
482         cp.security_level       = rx->min_sec_level;
483         cp.exclusive            = rx->exclusive | exclusive;
484         cp.upgrade              = upgrade;
485         cp.service_id           = srx->srx_service;
486         call = rxrpc_new_client_call(rx, &cp, srx, user_call_ID, GFP_KERNEL);
487         /* The socket is now unlocked */
488
489         _leave(" = %p\n", call);
490         return call;
491 }
492
493 /*
494  * send a message forming part of a client call through an RxRPC socket
495  * - caller holds the socket locked
496  * - the socket may be either a client socket or a server socket
497  */
498 int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
499         __releases(&rx->sk.sk_lock.slock)
500 {
501         enum rxrpc_call_state state;
502         enum rxrpc_command cmd;
503         struct rxrpc_call *call;
504         unsigned long user_call_ID = 0;
505         bool exclusive = false;
506         bool upgrade = true;
507         u32 abort_code = 0;
508         int ret;
509
510         _enter("");
511
512         ret = rxrpc_sendmsg_cmsg(msg, &user_call_ID, &cmd, &abort_code,
513                                  &exclusive, &upgrade);
514         if (ret < 0)
515                 goto error_release_sock;
516
517         if (cmd == RXRPC_CMD_ACCEPT) {
518                 ret = -EINVAL;
519                 if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
520                         goto error_release_sock;
521                 call = rxrpc_accept_call(rx, user_call_ID, NULL);
522                 /* The socket is now unlocked. */
523                 if (IS_ERR(call))
524                         return PTR_ERR(call);
525                 rxrpc_put_call(call, rxrpc_call_put);
526                 return 0;
527         }
528
529         call = rxrpc_find_call_by_user_ID(rx, user_call_ID);
530         if (!call) {
531                 ret = -EBADSLT;
532                 if (cmd != RXRPC_CMD_SEND_DATA)
533                         goto error_release_sock;
534                 call = rxrpc_new_client_call_for_sendmsg(rx, msg, user_call_ID,
535                                                          exclusive, upgrade);
536                 /* The socket is now unlocked... */
537                 if (IS_ERR(call))
538                         return PTR_ERR(call);
539                 /* ... and we have the call lock. */
540         } else {
541                 switch (READ_ONCE(call->state)) {
542                 case RXRPC_CALL_UNINITIALISED:
543                 case RXRPC_CALL_CLIENT_AWAIT_CONN:
544                 case RXRPC_CALL_SERVER_PREALLOC:
545                 case RXRPC_CALL_SERVER_SECURING:
546                 case RXRPC_CALL_SERVER_ACCEPTING:
547                         ret = -EBUSY;
548                         goto error_release_sock;
549                 default:
550                         break;
551                 }
552
553                 ret = mutex_lock_interruptible(&call->user_mutex);
554                 release_sock(&rx->sk);
555                 if (ret < 0) {
556                         ret = -ERESTARTSYS;
557                         goto error_put;
558                 }
559         }
560
561         state = READ_ONCE(call->state);
562         _debug("CALL %d USR %lx ST %d on CONN %p",
563                call->debug_id, call->user_call_ID, state, call->conn);
564
565         if (state >= RXRPC_CALL_COMPLETE) {
566                 /* it's too late for this call */
567                 ret = -ESHUTDOWN;
568         } else if (cmd == RXRPC_CMD_SEND_ABORT) {
569                 ret = 0;
570                 if (rxrpc_abort_call("CMD", call, 0, abort_code, -ECONNABORTED))
571                         ret = rxrpc_send_abort_packet(call);
572         } else if (cmd != RXRPC_CMD_SEND_DATA) {
573                 ret = -EINVAL;
574         } else if (rxrpc_is_client_call(call) &&
575                    state != RXRPC_CALL_CLIENT_SEND_REQUEST) {
576                 /* request phase complete for this client call */
577                 ret = -EPROTO;
578         } else if (rxrpc_is_service_call(call) &&
579                    state != RXRPC_CALL_SERVER_ACK_REQUEST &&
580                    state != RXRPC_CALL_SERVER_SEND_REPLY) {
581                 /* Reply phase not begun or not complete for service call. */
582                 ret = -EPROTO;
583         } else {
584                 ret = rxrpc_send_data(rx, call, msg, len);
585         }
586
587         mutex_unlock(&call->user_mutex);
588 error_put:
589         rxrpc_put_call(call, rxrpc_call_put);
590         _leave(" = %d", ret);
591         return ret;
592
593 error_release_sock:
594         release_sock(&rx->sk);
595         return ret;
596 }
597
598 /**
599  * rxrpc_kernel_send_data - Allow a kernel service to send data on a call
600  * @sock: The socket the call is on
601  * @call: The call to send data through
602  * @msg: The data to send
603  * @len: The amount of data to send
604  *
605  * Allow a kernel service to send data on a call.  The call must be in an state
606  * appropriate to sending data.  No control data should be supplied in @msg,
607  * nor should an address be supplied.  MSG_MORE should be flagged if there's
608  * more data to come, otherwise this data will end the transmission phase.
609  */
610 int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
611                            struct msghdr *msg, size_t len)
612 {
613         int ret;
614
615         _enter("{%d,%s},", call->debug_id, rxrpc_call_states[call->state]);
616
617         ASSERTCMP(msg->msg_name, ==, NULL);
618         ASSERTCMP(msg->msg_control, ==, NULL);
619
620         mutex_lock(&call->user_mutex);
621
622         _debug("CALL %d USR %lx ST %d on CONN %p",
623                call->debug_id, call->user_call_ID, call->state, call->conn);
624
625         switch (READ_ONCE(call->state)) {
626         case RXRPC_CALL_CLIENT_SEND_REQUEST:
627         case RXRPC_CALL_SERVER_ACK_REQUEST:
628         case RXRPC_CALL_SERVER_SEND_REPLY:
629                 ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len);
630                 break;
631         case RXRPC_CALL_COMPLETE:
632                 read_lock_bh(&call->state_lock);
633                 ret = -call->error;
634                 read_unlock_bh(&call->state_lock);
635                 break;
636         default:
637                 /* Request phase complete for this client call */
638                 trace_rxrpc_rx_eproto(call, 0, tracepoint_string("late_send"));
639                 ret = -EPROTO;
640                 break;
641         }
642
643         mutex_unlock(&call->user_mutex);
644         _leave(" = %d", ret);
645         return ret;
646 }
647 EXPORT_SYMBOL(rxrpc_kernel_send_data);
648
649 /**
650  * rxrpc_kernel_abort_call - Allow a kernel service to abort a call
651  * @sock: The socket the call is on
652  * @call: The call to be aborted
653  * @abort_code: The abort code to stick into the ABORT packet
654  * @error: Local error value
655  * @why: 3-char string indicating why.
656  *
657  * Allow a kernel service to abort a call, if it's still in an abortable state
658  * and return true if the call was aborted, false if it was already complete.
659  */
660 bool rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
661                              u32 abort_code, int error, const char *why)
662 {
663         bool aborted;
664
665         _enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
666
667         mutex_lock(&call->user_mutex);
668
669         aborted = rxrpc_abort_call(why, call, 0, abort_code, error);
670         if (aborted)
671                 rxrpc_send_abort_packet(call);
672
673         mutex_unlock(&call->user_mutex);
674         return aborted;
675 }
676
677 EXPORT_SYMBOL(rxrpc_kernel_abort_call);