net/rxrpc/input.c

   1 /* RxRPC packet reception
   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 License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  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 <net/sock.h>
  24 #include <net/af_rxrpc.h>
  25 #include <net/ip.h>
  26 #include <net/udp.h>
  27 #include <net/net_namespace.h>
  28 #include "ar-internal.h"
  29
  30 static void rxrpc_proto_abort(const char *why,
  31                               struct rxrpc_call *call, rxrpc_seq_t seq)
  32 {
  33         if (rxrpc_abort_call(why, call, seq, RX_PROTOCOL_ERROR, EBADMSG)) {
  34                 set_bit(RXRPC_CALL_EV_ABORT, &call->events);
  35                 rxrpc_queue_call(call);
  36         }
  37 }
  38
  39 /*
  40  * Do TCP-style congestion management [RFC 5681].
  41  */
  42 static void rxrpc_congestion_management(struct rxrpc_call *call,
  43                                         struct sk_buff *skb,
  44                                         struct rxrpc_ack_summary *summary)
  45 {
  46         enum rxrpc_congest_change change = rxrpc_cong_no_change;
  47         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
  48         unsigned int cumulative_acks = call->cong_cumul_acks;
  49         unsigned int cwnd = call->cong_cwnd;
  50         bool resend = false;
  51
  52         summary->flight_size =
  53                 (call->tx_top - call->tx_hard_ack) - summary->nr_acks;
  54
  55         if (test_and_clear_bit(RXRPC_CALL_RETRANS_TIMEOUT, &call->flags)) {
  56                 summary->retrans_timeo = true;
  57                 call->cong_ssthresh = max_t(unsigned int,
  58                                             summary->flight_size / 2, 2);
  59                 cwnd = 1;
  60                 if (cwnd > call->cong_ssthresh &&
  61                     call->cong_mode == RXRPC_CALL_SLOW_START) {
  62                         call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
  63                         call->cong_tstamp = skb->tstamp;
  64                         cumulative_acks = 0;
  65                 }
  66         }
  67
  68         cumulative_acks += summary->nr_new_acks;
  69         cumulative_acks += summary->nr_rot_new_acks;
  70         if (cumulative_acks > 255)
  71                 cumulative_acks = 255;
  72
  73         summary->mode = call->cong_mode;
  74         summary->cwnd = call->cong_cwnd;
  75         summary->ssthresh = call->cong_ssthresh;
  76         summary->cumulative_acks = cumulative_acks;
  77         summary->dup_acks = call->cong_dup_acks;
  78
  79         switch (call->cong_mode) {
  80         case RXRPC_CALL_SLOW_START:
  81                 if (summary->nr_nacks > 0)
  82                         goto packet_loss_detected;
  83                 if (summary->cumulative_acks > 0)
  84                         cwnd += 1;
  85                 if (cwnd > call->cong_ssthresh) {
  86                         call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
  87                         call->cong_tstamp = skb->tstamp;
  88                 }
  89                 goto out;
  90
  91         case RXRPC_CALL_CONGEST_AVOIDANCE:
  92                 if (summary->nr_nacks > 0)
  93                         goto packet_loss_detected;
  94
  95                 /* We analyse the number of packets that get ACK'd per RTT
  96                  * period and increase the window if we managed to fill it.
  97                  */
  98                 if (call->peer->rtt_usage == 0)
  99                         goto out;
 100                 if (ktime_before(skb->tstamp,
 101                                  ktime_add_ns(call->cong_tstamp,
 102                                               call->peer->rtt)))
 103                         goto out_no_clear_ca;
 104                 change = rxrpc_cong_rtt_window_end;
 105                 call->cong_tstamp = skb->tstamp;
 106                 if (cumulative_acks >= cwnd)
 107                         cwnd++;
 108                 goto out;
 109
 110         case RXRPC_CALL_PACKET_LOSS:
 111                 if (summary->nr_nacks == 0)
 112                         goto resume_normality;
 113
 114                 if (summary->new_low_nack) {
 115                         change = rxrpc_cong_new_low_nack;
 116                         call->cong_dup_acks = 1;
 117                         if (call->cong_extra > 1)
 118                                 call->cong_extra = 1;
 119                         goto send_extra_data;
 120                 }
 121
 122                 call->cong_dup_acks++;
 123                 if (call->cong_dup_acks < 3)
 124                         goto send_extra_data;
 125
 126                 change = rxrpc_cong_begin_retransmission;
 127                 call->cong_mode = RXRPC_CALL_FAST_RETRANSMIT;
 128                 call->cong_ssthresh = max_t(unsigned int,
 129                                             summary->flight_size / 2, 2);
 130                 cwnd = call->cong_ssthresh + 3;
 131                 call->cong_extra = 0;
 132                 call->cong_dup_acks = 0;
 133                 resend = true;
 134                 goto out;
 135
 136         case RXRPC_CALL_FAST_RETRANSMIT:
 137                 if (!summary->new_low_nack) {
 138                         if (summary->nr_new_acks == 0)
 139                                 cwnd += 1;
 140                         call->cong_dup_acks++;
 141                         if (call->cong_dup_acks == 2) {
 142                                 change = rxrpc_cong_retransmit_again;
 143                                 call->cong_dup_acks = 0;
 144                                 resend = true;
 145                         }
 146                 } else {
 147                         change = rxrpc_cong_progress;
 148                         cwnd = call->cong_ssthresh;
 149                         if (summary->nr_nacks == 0)
 150                                 goto resume_normality;
 151                 }
 152                 goto out;
 153
 154         default:
 155                 BUG();
 156                 goto out;
 157         }
 158
 159 resume_normality:
 160         change = rxrpc_cong_cleared_nacks;
 161         call->cong_dup_acks = 0;
 162         call->cong_extra = 0;
 163         call->cong_tstamp = skb->tstamp;
 164         if (cwnd <= call->cong_ssthresh)
 165                 call->cong_mode = RXRPC_CALL_SLOW_START;
 166         else
 167                 call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
 168 out:
 169         cumulative_acks = 0;
 170 out_no_clear_ca:
 171         if (cwnd >= RXRPC_RXTX_BUFF_SIZE - 1)
 172                 cwnd = RXRPC_RXTX_BUFF_SIZE - 1;
 173         call->cong_cwnd = cwnd;
 174         call->cong_cumul_acks = cumulative_acks;
 175         trace_rxrpc_congest(call, summary, sp->hdr.serial, change);
 176         if (resend && !test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
 177                 rxrpc_queue_call(call);
 178         return;
 179
 180 packet_loss_detected:
 181         change = rxrpc_cong_saw_nack;
 182         call->cong_mode = RXRPC_CALL_PACKET_LOSS;
 183         call->cong_dup_acks = 0;
 184         goto send_extra_data;
 185
 186 send_extra_data:
 187         /* Send some previously unsent DATA if we have some to advance the ACK
 188          * state.
 189          */
 190         if (call->rxtx_annotations[call->tx_top & RXRPC_RXTX_BUFF_MASK] &
 191             RXRPC_TX_ANNO_LAST ||
 192             summary->nr_acks != call->tx_top - call->tx_hard_ack) {
 193                 call->cong_extra++;
 194                 wake_up(&call->waitq);
 195         }
 196         goto out_no_clear_ca;
 197 }
 198
 199 /*
 200  * Ping the other end to fill our RTT cache and to retrieve the rwind
 201  * and MTU parameters.
 202  */
 203 static void rxrpc_send_ping(struct rxrpc_call *call, struct sk_buff *skb,
 204                             int skew)
 205 {
 206         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 207         ktime_t now = skb->tstamp;
 208
 209         if (call->peer->rtt_usage < 3 ||
 210             ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000), now))
 211                 rxrpc_propose_ACK(call, RXRPC_ACK_PING, skew, sp->hdr.serial,
 212                                   true, true,
 213                                   rxrpc_propose_ack_ping_for_params);
 214 }
 215
 216 /*
 217  * Apply a hard ACK by advancing the Tx window.
 218  */
 219 static void rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to,
 220                                    struct rxrpc_ack_summary *summary)
 221 {
 222         struct sk_buff *skb, *list = NULL;
 223         int ix;
 224         u8 annotation;
 225
 226         if (call->acks_lowest_nak == call->tx_hard_ack) {
 227                 call->acks_lowest_nak = to;
 228         } else if (before_eq(call->acks_lowest_nak, to)) {
 229                 summary->new_low_nack = true;
 230                 call->acks_lowest_nak = to;
 231         }
 232
 233         spin_lock(&call->lock);
 234
 235         while (before(call->tx_hard_ack, to)) {
 236                 call->tx_hard_ack++;
 237                 ix = call->tx_hard_ack & RXRPC_RXTX_BUFF_MASK;
 238                 skb = call->rxtx_buffer[ix];
 239                 annotation = call->rxtx_annotations[ix];
 240                 rxrpc_see_skb(skb, rxrpc_skb_tx_rotated);
 241                 call->rxtx_buffer[ix] = NULL;
 242                 call->rxtx_annotations[ix] = 0;
 243                 skb->next = list;
 244                 list = skb;
 245
 246                 if (annotation & RXRPC_TX_ANNO_LAST)
 247                         set_bit(RXRPC_CALL_TX_LAST, &call->flags);
 248                 if ((annotation & RXRPC_TX_ANNO_MASK) != RXRPC_TX_ANNO_ACK)
 249                         summary->nr_rot_new_acks++;
 250         }
 251
 252         spin_unlock(&call->lock);
 253
 254         trace_rxrpc_transmit(call, (test_bit(RXRPC_CALL_TX_LAST, &call->flags) ?
 255                                     rxrpc_transmit_rotate_last :
 256                                     rxrpc_transmit_rotate));
 257         wake_up(&call->waitq);
 258
 259         while (list) {
 260                 skb = list;
 261                 list = skb->next;
 262                 skb->next = NULL;
 263                 rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
 264         }
 265 }
 266
 267 /*
 268  * End the transmission phase of a call.
 269  *
 270  * This occurs when we get an ACKALL packet, the first DATA packet of a reply,
 271  * or a final ACK packet.
 272  */
 273 static bool rxrpc_end_tx_phase(struct rxrpc_call *call, bool reply_begun,
 274                                const char *abort_why)
 275 {
 276
 277         ASSERT(test_bit(RXRPC_CALL_TX_LAST, &call->flags));
 278
 279         write_lock(&call->state_lock);
 280
 281         switch (call->state) {
 282         case RXRPC_CALL_CLIENT_SEND_REQUEST:
 283         case RXRPC_CALL_CLIENT_AWAIT_REPLY:
 284                 if (reply_begun)
 285                         call->state = RXRPC_CALL_CLIENT_RECV_REPLY;
 286                 else
 287                         call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
 288                 break;
 289
 290         case RXRPC_CALL_SERVER_AWAIT_ACK:
 291                 __rxrpc_call_completed(call);
 292                 rxrpc_notify_socket(call);
 293                 break;
 294
 295         default:
 296                 goto bad_state;
 297         }
 298
 299         write_unlock(&call->state_lock);
 300         if (call->state == RXRPC_CALL_CLIENT_AWAIT_REPLY) {
 301                 rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, 0, 0, false, true,
 302                                   rxrpc_propose_ack_client_tx_end);
 303                 trace_rxrpc_transmit(call, rxrpc_transmit_await_reply);
 304         } else {
 305                 trace_rxrpc_transmit(call, rxrpc_transmit_end);
 306         }
 307         _leave(" = ok");
 308         return true;
 309
 310 bad_state:
 311         write_unlock(&call->state_lock);
 312         kdebug("end_tx %s", rxrpc_call_states[call->state]);
 313         rxrpc_proto_abort(abort_why, call, call->tx_top);
 314         return false;
 315 }
 316
 317 /*
 318  * Begin the reply reception phase of a call.
 319  */
 320 static bool rxrpc_receiving_reply(struct rxrpc_call *call)
 321 {
 322         struct rxrpc_ack_summary summary = { 0 };
 323         rxrpc_seq_t top = READ_ONCE(call->tx_top);
 324
 325         if (call->ackr_reason) {
 326                 spin_lock_bh(&call->lock);
 327                 call->ackr_reason = 0;
 328                 call->resend_at = call->expire_at;
 329                 call->ack_at = call->expire_at;
 330                 spin_unlock_bh(&call->lock);
 331                 rxrpc_set_timer(call, rxrpc_timer_init_for_reply);
 332         }
 333
 334         if (!test_bit(RXRPC_CALL_TX_LAST, &call->flags))
 335                 rxrpc_rotate_tx_window(call, top, &summary);
 336         if (!test_bit(RXRPC_CALL_TX_LAST, &call->flags)) {
 337                 rxrpc_proto_abort("TXL", call, top);
 338                 return false;
 339         }
 340         if (!rxrpc_end_tx_phase(call, true, "ETD"))
 341                 return false;
 342         call->tx_phase = false;
 343         return true;
 344 }
 345
 346 /*
 347  * Scan a jumbo packet to validate its structure and to work out how many
 348  * subpackets it contains.
 349  *
 350  * A jumbo packet is a collection of consecutive packets glued together with
 351  * little headers between that indicate how to change the initial header for
 352  * each subpacket.
 353  *
 354  * RXRPC_JUMBO_PACKET must be set on all but the last subpacket - and all but
 355  * the last are RXRPC_JUMBO_DATALEN in size.  The last subpacket may be of any
 356  * size.
 357  */
 358 static bool rxrpc_validate_jumbo(struct sk_buff *skb)
 359 {
 360         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 361         unsigned int offset = sp->offset;
 362         unsigned int len = skb->len;
 363         int nr_jumbo = 1;
 364         u8 flags = sp->hdr.flags;
 365
 366         do {
 367                 nr_jumbo++;
 368                 if (len - offset < RXRPC_JUMBO_SUBPKTLEN)
 369                         goto protocol_error;
 370                 if (flags & RXRPC_LAST_PACKET)
 371                         goto protocol_error;
 372                 offset += RXRPC_JUMBO_DATALEN;
 373                 if (skb_copy_bits(skb, offset, &flags, 1) < 0)
 374                         goto protocol_error;
 375                 offset += sizeof(struct rxrpc_jumbo_header);
 376         } while (flags & RXRPC_JUMBO_PACKET);
 377
 378         sp->nr_jumbo = nr_jumbo;
 379         return true;
 380
 381 protocol_error:
 382         return false;
 383 }
 384
 385 /*
 386  * Handle reception of a duplicate packet.
 387  *
 388  * We have to take care to avoid an attack here whereby we're given a series of
 389  * jumbograms, each with a sequence number one before the preceding one and
 390  * filled up to maximum UDP size.  If they never send us the first packet in
 391  * the sequence, they can cause us to have to hold on to around 2MiB of kernel
 392  * space until the call times out.
 393  *
 394  * We limit the space usage by only accepting three duplicate jumbo packets per
 395  * call.  After that, we tell the other side we're no longer accepting jumbos
 396  * (that information is encoded in the ACK packet).
 397  */
 398 static void rxrpc_input_dup_data(struct rxrpc_call *call, rxrpc_seq_t seq,
 399                                  u8 annotation, bool *_jumbo_bad)
 400 {
 401         /* Discard normal packets that are duplicates. */
 402         if (annotation == 0)
 403                 return;
 404
 405         /* Skip jumbo subpackets that are duplicates.  When we've had three or
 406          * more partially duplicate jumbo packets, we refuse to take any more
 407          * jumbos for this call.
 408          */
 409         if (!*_jumbo_bad) {
 410                 call->nr_jumbo_bad++;
 411                 *_jumbo_bad = true;
 412         }
 413 }
 414
 415 /*
 416  * Process a DATA packet, adding the packet to the Rx ring.
 417  */
 418 static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb,
 419                              u16 skew)
 420 {
 421         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 422         unsigned int offset = sp->offset;
 423         unsigned int ix;
 424         rxrpc_serial_t serial = sp->hdr.serial, ack_serial = 0;
 425         rxrpc_seq_t seq = sp->hdr.seq, hard_ack;
 426         bool immediate_ack = false, jumbo_bad = false, queued;
 427         u16 len;
 428         u8 ack = 0, flags, annotation = 0;
 429
 430         _enter("{%u,%u},{%u,%u}",
 431                call->rx_hard_ack, call->rx_top, skb->len, seq);
 432
 433         _proto("Rx DATA %%%u { #%u f=%02x }",
 434                sp->hdr.serial, seq, sp->hdr.flags);
 435
 436         if (call->state >= RXRPC_CALL_COMPLETE)
 437                 return;
 438
 439         /* Received data implicitly ACKs all of the request packets we sent
 440          * when we're acting as a client.
 441          */
 442         if ((call->state == RXRPC_CALL_CLIENT_SEND_REQUEST ||
 443              call->state == RXRPC_CALL_CLIENT_AWAIT_REPLY) &&
 444             !rxrpc_receiving_reply(call))
 445                 return;
 446
 447         call->ackr_prev_seq = seq;
 448
 449         hard_ack = READ_ONCE(call->rx_hard_ack);
 450         if (after(seq, hard_ack + call->rx_winsize)) {
 451                 ack = RXRPC_ACK_EXCEEDS_WINDOW;
 452                 ack_serial = serial;
 453                 goto ack;
 454         }
 455
 456         flags = sp->hdr.flags;
 457         if (flags & RXRPC_JUMBO_PACKET) {
 458                 if (call->nr_jumbo_bad > 3) {
 459                         ack = RXRPC_ACK_NOSPACE;
 460                         ack_serial = serial;
 461                         goto ack;
 462                 }
 463                 annotation = 1;
 464         }
 465
 466 next_subpacket:
 467         queued = false;
 468         ix = seq & RXRPC_RXTX_BUFF_MASK;
 469         len = skb->len;
 470         if (flags & RXRPC_JUMBO_PACKET)
 471                 len = RXRPC_JUMBO_DATALEN;
 472
 473         if (flags & RXRPC_LAST_PACKET) {
 474                 if (test_bit(RXRPC_CALL_RX_LAST, &call->flags) &&
 475                     seq != call->rx_top)
 476                         return rxrpc_proto_abort("LSN", call, seq);
 477         } else {
 478                 if (test_bit(RXRPC_CALL_RX_LAST, &call->flags) &&
 479                     after_eq(seq, call->rx_top))
 480                         return rxrpc_proto_abort("LSA", call, seq);
 481         }
 482
 483         if (before_eq(seq, hard_ack)) {
 484                 ack = RXRPC_ACK_DUPLICATE;
 485                 ack_serial = serial;
 486                 goto skip;
 487         }
 488
 489         if (flags & RXRPC_REQUEST_ACK && !ack) {
 490                 ack = RXRPC_ACK_REQUESTED;
 491                 ack_serial = serial;
 492         }
 493
 494         if (call->rxtx_buffer[ix]) {
 495                 rxrpc_input_dup_data(call, seq, annotation, &jumbo_bad);
 496                 if (ack != RXRPC_ACK_DUPLICATE) {
 497                         ack = RXRPC_ACK_DUPLICATE;
 498                         ack_serial = serial;
 499                 }
 500                 immediate_ack = true;
 501                 goto skip;
 502         }
 503
 504         /* Queue the packet.  We use a couple of memory barriers here as need
 505          * to make sure that rx_top is perceived to be set after the buffer
 506          * pointer and that the buffer pointer is set after the annotation and
 507          * the skb data.
 508          *
 509          * Barriers against rxrpc_recvmsg_data() and rxrpc_rotate_rx_window()
 510          * and also rxrpc_fill_out_ack().
 511          */
 512         rxrpc_get_skb(skb, rxrpc_skb_rx_got);
 513         call->rxtx_annotations[ix] = annotation;
 514         smp_wmb();
 515         call->rxtx_buffer[ix] = skb;
 516         if (after(seq, call->rx_top)) {
 517                 smp_store_release(&call->rx_top, seq);
 518         } else if (before(seq, call->rx_top)) {
 519                 /* Send an immediate ACK if we fill in a hole */
 520                 if (!ack) {
 521                         ack = RXRPC_ACK_DELAY;
 522                         ack_serial = serial;
 523                 }
 524                 immediate_ack = true;
 525         }
 526         if (flags & RXRPC_LAST_PACKET) {
 527                 set_bit(RXRPC_CALL_RX_LAST, &call->flags);
 528                 trace_rxrpc_receive(call, rxrpc_receive_queue_last, serial, seq);
 529         } else {
 530                 trace_rxrpc_receive(call, rxrpc_receive_queue, serial, seq);
 531         }
 532         queued = true;
 533
 534         if (after_eq(seq, call->rx_expect_next)) {
 535                 if (after(seq, call->rx_expect_next)) {
 536                         _net("OOS %u > %u", seq, call->rx_expect_next);
 537                         ack = RXRPC_ACK_OUT_OF_SEQUENCE;
 538                         ack_serial = serial;
 539                 }
 540                 call->rx_expect_next = seq + 1;
 541         }
 542
 543 skip:
 544         offset += len;
 545         if (flags & RXRPC_JUMBO_PACKET) {
 546                 if (skb_copy_bits(skb, offset, &flags, 1) < 0)
 547                         return rxrpc_proto_abort("XJF", call, seq);
 548                 offset += sizeof(struct rxrpc_jumbo_header);
 549                 seq++;
 550                 serial++;
 551                 annotation++;
 552                 if (flags & RXRPC_JUMBO_PACKET)
 553                         annotation |= RXRPC_RX_ANNO_JLAST;
 554                 if (after(seq, hard_ack + call->rx_winsize)) {
 555                         ack = RXRPC_ACK_EXCEEDS_WINDOW;
 556                         ack_serial = serial;
 557                         if (!jumbo_bad) {
 558                                 call->nr_jumbo_bad++;
 559                                 jumbo_bad = true;
 560                         }
 561                         goto ack;
 562                 }
 563
 564                 _proto("Rx DATA Jumbo %%%u", serial);
 565                 goto next_subpacket;
 566         }
 567
 568         if (queued && flags & RXRPC_LAST_PACKET && !ack) {
 569                 ack = RXRPC_ACK_DELAY;
 570                 ack_serial = serial;
 571         }
 572
 573 ack:
 574         if (ack)
 575                 rxrpc_propose_ACK(call, ack, skew, ack_serial,
 576                                   immediate_ack, true,
 577                                   rxrpc_propose_ack_input_data);
 578
 579         if (sp->hdr.seq == READ_ONCE(call->rx_hard_ack) + 1)
 580                 rxrpc_notify_socket(call);
 581         _leave(" [queued]");
 582 }
 583
 584 /*
 585  * Process a requested ACK.
 586  */
 587 static void rxrpc_input_requested_ack(struct rxrpc_call *call,
 588                                       ktime_t resp_time,
 589                                       rxrpc_serial_t orig_serial,
 590                                       rxrpc_serial_t ack_serial)
 591 {
 592         struct rxrpc_skb_priv *sp;
 593         struct sk_buff *skb;
 594         ktime_t sent_at;
 595         int ix;
 596
 597         for (ix = 0; ix < RXRPC_RXTX_BUFF_SIZE; ix++) {
 598                 skb = call->rxtx_buffer[ix];
 599                 if (!skb)
 600                         continue;
 601
 602                 sp = rxrpc_skb(skb);
 603                 if (sp->hdr.serial != orig_serial)
 604                         continue;
 605                 smp_rmb();
 606                 sent_at = skb->tstamp;
 607                 goto found;
 608         }
 609         return;
 610
 611 found:
 612         rxrpc_peer_add_rtt(call, rxrpc_rtt_rx_requested_ack,
 613                            orig_serial, ack_serial, sent_at, resp_time);
 614 }
 615
 616 /*
 617  * Process a ping response.
 618  */
 619 static void rxrpc_input_ping_response(struct rxrpc_call *call,
 620                                       ktime_t resp_time,
 621                                       rxrpc_serial_t orig_serial,
 622                                       rxrpc_serial_t ack_serial)
 623 {
 624         rxrpc_serial_t ping_serial;
 625         ktime_t ping_time;
 626
 627         ping_time = call->ackr_ping_time;
 628         smp_rmb();
 629         ping_serial = call->ackr_ping;
 630
 631         if (!test_bit(RXRPC_CALL_PINGING, &call->flags) ||
 632             before(orig_serial, ping_serial))
 633                 return;
 634         clear_bit(RXRPC_CALL_PINGING, &call->flags);
 635         if (after(orig_serial, ping_serial))
 636                 return;
 637
 638         rxrpc_peer_add_rtt(call, rxrpc_rtt_rx_ping_response,
 639                            orig_serial, ack_serial, ping_time, resp_time);
 640 }
 641
 642 /*
 643  * Process the extra information that may be appended to an ACK packet
 644  */
 645 static void rxrpc_input_ackinfo(struct rxrpc_call *call, struct sk_buff *skb,
 646                                 struct rxrpc_ackinfo *ackinfo)
 647 {
 648         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 649         struct rxrpc_peer *peer;
 650         unsigned int mtu;
 651         u32 rwind = ntohl(ackinfo->rwind);
 652
 653         _proto("Rx ACK %%%u Info { rx=%u max=%u rwin=%u jm=%u }",
 654                sp->hdr.serial,
 655                ntohl(ackinfo->rxMTU), ntohl(ackinfo->maxMTU),
 656                rwind, ntohl(ackinfo->jumbo_max));
 657
 658         if (rwind > RXRPC_RXTX_BUFF_SIZE - 1)
 659                 rwind = RXRPC_RXTX_BUFF_SIZE - 1;
 660         call->tx_winsize = rwind;
 661
 662         mtu = min(ntohl(ackinfo->rxMTU), ntohl(ackinfo->maxMTU));
 663
 664         peer = call->peer;
 665         if (mtu < peer->maxdata) {
 666                 spin_lock_bh(&peer->lock);
 667                 peer->maxdata = mtu;
 668                 peer->mtu = mtu + peer->hdrsize;
 669                 spin_unlock_bh(&peer->lock);
 670                 _net("Net MTU %u (maxdata %u)", peer->mtu, peer->maxdata);
 671         }
 672 }
 673
 674 /*
 675  * Process individual soft ACKs.
 676  *
 677  * Each ACK in the array corresponds to one packet and can be either an ACK or
 678  * a NAK.  If we get find an explicitly NAK'd packet we resend immediately;
 679  * packets that lie beyond the end of the ACK list are scheduled for resend by
 680  * the timer on the basis that the peer might just not have processed them at
 681  * the time the ACK was sent.
 682  */
 683 static void rxrpc_input_soft_acks(struct rxrpc_call *call, u8 *acks,
 684                                   rxrpc_seq_t seq, int nr_acks,
 685                                   struct rxrpc_ack_summary *summary)
 686 {
 687         int ix;
 688         u8 annotation, anno_type;
 689
 690         for (; nr_acks > 0; nr_acks--, seq++) {
 691                 ix = seq & RXRPC_RXTX_BUFF_MASK;
 692                 annotation = call->rxtx_annotations[ix];
 693                 anno_type = annotation & RXRPC_TX_ANNO_MASK;
 694                 annotation &= ~RXRPC_TX_ANNO_MASK;
 695                 switch (*acks++) {
 696                 case RXRPC_ACK_TYPE_ACK:
 697                         summary->nr_acks++;
 698                         if (anno_type == RXRPC_TX_ANNO_ACK)
 699                                 continue;
 700                         summary->nr_new_acks++;
 701                         call->rxtx_annotations[ix] =
 702                                 RXRPC_TX_ANNO_ACK | annotation;
 703                         break;
 704                 case RXRPC_ACK_TYPE_NACK:
 705                         if (!summary->nr_nacks &&
 706                             call->acks_lowest_nak != seq) {
 707                                 call->acks_lowest_nak = seq;
 708                                 summary->new_low_nack = true;
 709                         }
 710                         summary->nr_nacks++;
 711                         if (anno_type == RXRPC_TX_ANNO_NAK)
 712                                 continue;
 713                         summary->nr_new_nacks++;
 714                         if (anno_type == RXRPC_TX_ANNO_RETRANS)
 715                                 continue;
 716                         call->rxtx_annotations[ix] =
 717                                 RXRPC_TX_ANNO_NAK | annotation;
 718                         break;
 719                 default:
 720                         return rxrpc_proto_abort("SFT", call, 0);
 721                 }
 722         }
 723 }
 724
 725 /*
 726  * Process an ACK packet.
 727  *
 728  * ack.firstPacket is the sequence number of the first soft-ACK'd/NAK'd packet
 729  * in the ACK array.  Anything before that is hard-ACK'd and may be discarded.
 730  *
 731  * A hard-ACK means that a packet has been processed and may be discarded; a
 732  * soft-ACK means that the packet may be discarded and retransmission
 733  * requested.  A phase is complete when all packets are hard-ACK'd.
 734  */
 735 static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb,
 736                             u16 skew)
 737 {
 738         struct rxrpc_ack_summary summary = { 0 };
 739         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 740         union {
 741                 struct rxrpc_ackpacket ack;
 742                 struct rxrpc_ackinfo info;
 743                 u8 acks[RXRPC_MAXACKS];
 744         } buf;
 745         rxrpc_serial_t acked_serial;
 746         rxrpc_seq_t first_soft_ack, hard_ack;
 747         int nr_acks, offset;
 748
 749         _enter("");
 750
 751         if (skb_copy_bits(skb, sp->offset, &buf.ack, sizeof(buf.ack)) < 0) {
 752                 _debug("extraction failure");
 753                 return rxrpc_proto_abort("XAK", call, 0);
 754         }
 755         sp->offset += sizeof(buf.ack);
 756
 757         acked_serial = ntohl(buf.ack.serial);
 758         first_soft_ack = ntohl(buf.ack.firstPacket);
 759         hard_ack = first_soft_ack - 1;
 760         nr_acks = buf.ack.nAcks;
 761         summary.ack_reason = (buf.ack.reason < RXRPC_ACK__INVALID ?
 762                               buf.ack.reason : RXRPC_ACK__INVALID);
 763
 764         trace_rxrpc_rx_ack(call, first_soft_ack, summary.ack_reason, nr_acks);
 765
 766         _proto("Rx ACK %%%u { m=%hu f=#%u p=#%u s=%%%u r=%s n=%u }",
 767                sp->hdr.serial,
 768                ntohs(buf.ack.maxSkew),
 769                first_soft_ack,
 770                ntohl(buf.ack.previousPacket),
 771                acked_serial,
 772                rxrpc_ack_names[summary.ack_reason],
 773                buf.ack.nAcks);
 774
 775         if (buf.ack.reason == RXRPC_ACK_PING_RESPONSE)
 776                 rxrpc_input_ping_response(call, skb->tstamp, acked_serial,
 777                                           sp->hdr.serial);
 778         if (buf.ack.reason == RXRPC_ACK_REQUESTED)
 779                 rxrpc_input_requested_ack(call, skb->tstamp, acked_serial,
 780                                           sp->hdr.serial);
 781
 782         if (buf.ack.reason == RXRPC_ACK_PING) {
 783                 _proto("Rx ACK %%%u PING Request", sp->hdr.serial);
 784                 rxrpc_propose_ACK(call, RXRPC_ACK_PING_RESPONSE,
 785                                   skew, sp->hdr.serial, true, true,
 786                                   rxrpc_propose_ack_respond_to_ping);
 787         } else if (sp->hdr.flags & RXRPC_REQUEST_ACK) {
 788                 rxrpc_propose_ACK(call, RXRPC_ACK_REQUESTED,
 789                                   skew, sp->hdr.serial, true, true,
 790                                   rxrpc_propose_ack_respond_to_ack);
 791         }
 792
 793         offset = sp->offset + nr_acks + 3;
 794         if (skb->len >= offset + sizeof(buf.info)) {
 795                 if (skb_copy_bits(skb, offset, &buf.info, sizeof(buf.info)) < 0)
 796                         return rxrpc_proto_abort("XAI", call, 0);
 797                 rxrpc_input_ackinfo(call, skb, &buf.info);
 798         }
 799
 800         if (first_soft_ack == 0)
 801                 return rxrpc_proto_abort("AK0", call, 0);
 802
 803         /* Ignore ACKs unless we are or have just been transmitting. */
 804         switch (call->state) {
 805         case RXRPC_CALL_CLIENT_SEND_REQUEST:
 806         case RXRPC_CALL_CLIENT_AWAIT_REPLY:
 807         case RXRPC_CALL_SERVER_SEND_REPLY:
 808         case RXRPC_CALL_SERVER_AWAIT_ACK:
 809                 break;
 810         default:
 811                 return;
 812         }
 813
 814         /* Discard any out-of-order or duplicate ACKs. */
 815         if (before_eq(sp->hdr.serial, call->acks_latest)) {
 816                 _debug("discard ACK %d <= %d",
 817                        sp->hdr.serial, call->acks_latest);
 818                 return;
 819         }
 820         call->acks_latest_ts = skb->tstamp;
 821         call->acks_latest = sp->hdr.serial;
 822
 823         if (before(hard_ack, call->tx_hard_ack) ||
 824             after(hard_ack, call->tx_top))
 825                 return rxrpc_proto_abort("AKW", call, 0);
 826         if (nr_acks > call->tx_top - hard_ack)
 827                 return rxrpc_proto_abort("AKN", call, 0);
 828
 829         if (after(hard_ack, call->tx_hard_ack))
 830                 rxrpc_rotate_tx_window(call, hard_ack, &summary);
 831
 832         if (nr_acks > 0) {
 833                 if (skb_copy_bits(skb, sp->offset, buf.acks, nr_acks) < 0)
 834                         return rxrpc_proto_abort("XSA", call, 0);
 835                 rxrpc_input_soft_acks(call, buf.acks, first_soft_ack, nr_acks,
 836                                       &summary);
 837         }
 838
 839         if (test_bit(RXRPC_CALL_TX_LAST, &call->flags)) {
 840                 rxrpc_end_tx_phase(call, false, "ETA");
 841                 return;
 842         }
 843
 844         if (call->rxtx_annotations[call->tx_top & RXRPC_RXTX_BUFF_MASK] &
 845             RXRPC_TX_ANNO_LAST &&
 846             summary.nr_acks == call->tx_top - hard_ack)
 847                 rxrpc_propose_ACK(call, RXRPC_ACK_PING, skew, sp->hdr.serial,
 848                                   false, true,
 849                                   rxrpc_propose_ack_ping_for_lost_reply);
 850
 851         return rxrpc_congestion_management(call, skb, &summary);
 852 }
 853
 854 /*
 855  * Process an ACKALL packet.
 856  */
 857 static void rxrpc_input_ackall(struct rxrpc_call *call, struct sk_buff *skb)
 858 {
 859         struct rxrpc_ack_summary summary = { 0 };
 860         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 861
 862         _proto("Rx ACKALL %%%u", sp->hdr.serial);
 863
 864         rxrpc_rotate_tx_window(call, call->tx_top, &summary);
 865         if (test_bit(RXRPC_CALL_TX_LAST, &call->flags))
 866                 rxrpc_end_tx_phase(call, false, "ETL");
 867 }
 868
 869 /*
 870  * Process an ABORT packet.
 871  */
 872 static void rxrpc_input_abort(struct rxrpc_call *call, struct sk_buff *skb)
 873 {
 874         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 875         __be32 wtmp;
 876         u32 abort_code = RX_CALL_DEAD;
 877
 878         _enter("");
 879
 880         if (skb->len >= 4 &&
 881             skb_copy_bits(skb, sp->offset, &wtmp, sizeof(wtmp)) >= 0)
 882                 abort_code = ntohl(wtmp);
 883
 884         _proto("Rx ABORT %%%u { %x }", sp->hdr.serial, abort_code);
 885
 886         if (rxrpc_set_call_completion(call, RXRPC_CALL_REMOTELY_ABORTED,
 887                                       abort_code, ECONNABORTED))
 888                 rxrpc_notify_socket(call);
 889 }
 890
 891 /*
 892  * Process an incoming call packet.
 893  */
 894 static void rxrpc_input_call_packet(struct rxrpc_call *call,
 895                                     struct sk_buff *skb, u16 skew)
 896 {
 897         struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
 898
 899         _enter("%p,%p", call, skb);
 900
 901         switch (sp->hdr.type) {
 902         case RXRPC_PACKET_TYPE_DATA:
 903                 rxrpc_input_data(call, skb, skew);
 904                 break;
 905
 906         case RXRPC_PACKET_TYPE_ACK:
 907                 rxrpc_input_ack(call, skb, skew);
 908                 break;
 909
 910         case RXRPC_PACKET_TYPE_BUSY:
 911                 _proto("Rx BUSY %%%u", sp->hdr.serial);
 912
 913                 /* Just ignore BUSY packets from the server; the retry and
 914                  * lifespan timers will take care of business.  BUSY packets
 915                  * from the client don't make sense.
 916                  */
 917                 break;
 918
 919         case RXRPC_PACKET_TYPE_ABORT:
 920                 rxrpc_input_abort(call, skb);
 921                 break;
 922
 923         case RXRPC_PACKET_TYPE_ACKALL:
 924                 rxrpc_input_ackall(call, skb);
 925                 break;
 926
 927         default:
 928                 _proto("Rx %s %%%u", rxrpc_pkts[sp->hdr.type], sp->hdr.serial);
 929                 break;
 930         }
 931
 932         _leave("");
 933 }
 934
 935 /*
 936  * post connection-level events to the connection
 937  * - this includes challenges, responses, some aborts and call terminal packet
 938  *   retransmission.
 939  */
 940 static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn,
 941                                       struct sk_buff *skb)
 942 {
 943         _enter("%p,%p", conn, skb);
 944
 945         skb_queue_tail(&conn->rx_queue, skb);
 946         rxrpc_queue_conn(conn);
 947 }
 948
 949 /*
 950  * post endpoint-level events to the local endpoint
 951  * - this includes debug and version messages
 952  */
 953 static void rxrpc_post_packet_to_local(struct rxrpc_local *local,
 954                                        struct sk_buff *skb)
 955 {
 956         _enter("%p,%p", local, skb);
 957
 958         skb_queue_tail(&local->event_queue, skb);
 959         rxrpc_queue_local(local);
 960 }
 961
 962 /*
 963  * put a packet up for transport-level abort
 964  */
 965 static void rxrpc_reject_packet(struct rxrpc_local *local, struct sk_buff *skb)
 966 {
 967         CHECK_SLAB_OKAY(&local->usage);
 968
 969         skb_queue_tail(&local->reject_queue, skb);
 970         rxrpc_queue_local(local);
 971 }
 972
 973 /*
 974  * Extract the wire header from a packet and translate the byte order.
 975  */
 976 static noinline
 977 int rxrpc_extract_header(struct rxrpc_skb_priv *sp, struct sk_buff *skb)
 978 {
 979         struct rxrpc_wire_header whdr;
 980
 981         /* dig out the RxRPC connection details */
 982         if (skb_copy_bits(skb, 0, &whdr, sizeof(whdr)) < 0)
 983                 return -EBADMSG;
 984
 985         memset(sp, 0, sizeof(*sp));
 986         sp->hdr.epoch           = ntohl(whdr.epoch);
 987         sp->hdr.cid             = ntohl(whdr.cid);
 988         sp->hdr.callNumber      = ntohl(whdr.callNumber);
 989         sp->hdr.seq             = ntohl(whdr.seq);
 990         sp->hdr.serial          = ntohl(whdr.serial);
 991         sp->hdr.flags           = whdr.flags;
 992         sp->hdr.type            = whdr.type;
 993         sp->hdr.userStatus      = whdr.userStatus;
 994         sp->hdr.securityIndex   = whdr.securityIndex;
 995         sp->hdr._rsvd           = ntohs(whdr._rsvd);
 996         sp->hdr.serviceId       = ntohs(whdr.serviceId);
 997         sp->offset = sizeof(whdr);
 998         return 0;
 999 }
1000
1001 /*
1002  * handle data received on the local endpoint
1003  * - may be called in interrupt context
1004  *
1005  * The socket is locked by the caller and this prevents the socket from being
1006  * shut down and the local endpoint from going away, thus sk_user_data will not
1007  * be cleared until this function returns.
1008  */
1009 void rxrpc_data_ready(struct sock *udp_sk)
1010 {
1011         struct rxrpc_connection *conn;
1012         struct rxrpc_channel *chan;
1013         struct rxrpc_call *call;
1014         struct rxrpc_skb_priv *sp;
1015         struct rxrpc_local *local = udp_sk->sk_user_data;
1016         struct sk_buff *skb;
1017         unsigned int channel;
1018         int ret, skew;
1019
1020         _enter("%p", udp_sk);
1021
1022         ASSERT(!irqs_disabled());
1023
1024         skb = skb_recv_datagram(udp_sk, 0, 1, &ret);
1025         if (!skb) {
1026                 if (ret == -EAGAIN)
1027                         return;
1028                 _debug("UDP socket error %d", ret);
1029                 return;
1030         }
1031
1032         rxrpc_new_skb(skb, rxrpc_skb_rx_received);
1033
1034         _net("recv skb %p", skb);
1035
1036         /* we'll probably need to checksum it (didn't call sock_recvmsg) */
1037         if (skb_checksum_complete(skb)) {
1038                 rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
1039                 __UDP_INC_STATS(&init_net, UDP_MIB_INERRORS, 0);
1040                 _leave(" [CSUM failed]");
1041                 return;
1042         }
1043
1044         __UDP_INC_STATS(&init_net, UDP_MIB_INDATAGRAMS, 0);
1045
1046         /* The socket buffer we have is owned by UDP, with UDP's data all over
1047          * it, but we really want our own data there.
1048          */
1049         skb_orphan(skb);
1050         sp = rxrpc_skb(skb);
1051
1052         /* dig out the RxRPC connection details */
1053         if (rxrpc_extract_header(sp, skb) < 0)
1054                 goto bad_message;
1055
1056         if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) {
1057                 static int lose;
1058                 if ((lose++ & 7) == 7) {
1059                         trace_rxrpc_rx_lose(sp);
1060                         rxrpc_lose_skb(skb, rxrpc_skb_rx_lost);
1061                         return;
1062                 }
1063         }
1064
1065         trace_rxrpc_rx_packet(sp);
1066
1067         _net("Rx RxRPC %s ep=%x call=%x:%x",
1068              sp->hdr.flags & RXRPC_CLIENT_INITIATED ? "ToServer" : "ToClient",
1069              sp->hdr.epoch, sp->hdr.cid, sp->hdr.callNumber);
1070
1071         if (sp->hdr.type >= RXRPC_N_PACKET_TYPES ||
1072             !((RXRPC_SUPPORTED_PACKET_TYPES >> sp->hdr.type) & 1)) {
1073                 _proto("Rx Bad Packet Type %u", sp->hdr.type);
1074                 goto bad_message;
1075         }
1076
1077         switch (sp->hdr.type) {
1078         case RXRPC_PACKET_TYPE_VERSION:
1079                 rxrpc_post_packet_to_local(local, skb);
1080                 goto out;
1081
1082         case RXRPC_PACKET_TYPE_BUSY:
1083                 if (sp->hdr.flags & RXRPC_CLIENT_INITIATED)
1084                         goto discard;
1085
1086         case RXRPC_PACKET_TYPE_DATA:
1087                 if (sp->hdr.callNumber == 0)
1088                         goto bad_message;
1089                 if (sp->hdr.flags & RXRPC_JUMBO_PACKET &&
1090                     !rxrpc_validate_jumbo(skb))
1091                         goto bad_message;
1092                 break;
1093         }
1094
1095         rcu_read_lock();
1096
1097         conn = rxrpc_find_connection_rcu(local, skb);
1098         if (conn) {
1099                 if (sp->hdr.securityIndex != conn->security_ix)
1100                         goto wrong_security;
1101
1102                 if (sp->hdr.callNumber == 0) {
1103                         /* Connection-level packet */
1104                         _debug("CONN %p {%d}", conn, conn->debug_id);
1105                         rxrpc_post_packet_to_conn(conn, skb);
1106                         goto out_unlock;
1107                 }
1108
1109                 /* Note the serial number skew here */
1110                 skew = (int)sp->hdr.serial - (int)conn->hi_serial;
1111                 if (skew >= 0) {
1112                         if (skew > 0)
1113                                 conn->hi_serial = sp->hdr.serial;
1114                 } else {
1115                         skew = -skew;
1116                         skew = min(skew, 65535);
1117                 }
1118
1119                 /* Call-bound packets are routed by connection channel. */
1120                 channel = sp->hdr.cid & RXRPC_CHANNELMASK;
1121                 chan = &conn->channels[channel];
1122
1123                 /* Ignore really old calls */
1124                 if (sp->hdr.callNumber < chan->last_call)
1125                         goto discard_unlock;
1126
1127                 if (sp->hdr.callNumber == chan->last_call) {
1128                         /* For the previous service call, if completed successfully, we
1129                          * discard all further packets.
1130                          */
1131                         if (rxrpc_conn_is_service(conn) &&
1132                             (chan->last_type == RXRPC_PACKET_TYPE_ACK ||
1133                              sp->hdr.type == RXRPC_PACKET_TYPE_ABORT))
1134                                 goto discard_unlock;
1135
1136                         /* But otherwise we need to retransmit the final packet from
1137                          * data cached in the connection record.
1138                          */
1139                         rxrpc_post_packet_to_conn(conn, skb);
1140                         goto out_unlock;
1141                 }
1142
1143                 call = rcu_dereference(chan->call);
1144         } else {
1145                 skew = 0;
1146                 call = NULL;
1147         }
1148
1149         if (!call || atomic_read(&call->usage) == 0) {
1150                 if (!(sp->hdr.type & RXRPC_CLIENT_INITIATED) ||
1151                     sp->hdr.callNumber == 0 ||
1152                     sp->hdr.type != RXRPC_PACKET_TYPE_DATA)
1153                         goto bad_message_unlock;
1154                 if (sp->hdr.seq != 1)
1155                         goto discard_unlock;
1156                 call = rxrpc_new_incoming_call(local, conn, skb);
1157                 if (!call) {
1158                         rcu_read_unlock();
1159                         goto reject_packet;
1160                 }
1161                 rxrpc_send_ping(call, skb, skew);
1162         }
1163
1164         rxrpc_input_call_packet(call, skb, skew);
1165         goto discard_unlock;
1166
1167 discard_unlock:
1168         rcu_read_unlock();
1169 discard:
1170         rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
1171 out:
1172         trace_rxrpc_rx_done(0, 0);
1173         return;
1174
1175 out_unlock:
1176         rcu_read_unlock();
1177         goto out;
1178
1179 wrong_security:
1180         rcu_read_unlock();
1181         trace_rxrpc_abort("SEC", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
1182                           RXKADINCONSISTENCY, EBADMSG);
1183         skb->priority = RXKADINCONSISTENCY;
1184         goto post_abort;
1185
1186 bad_message_unlock:
1187         rcu_read_unlock();
1188 bad_message:
1189         trace_rxrpc_abort("BAD", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
1190                           RX_PROTOCOL_ERROR, EBADMSG);
1191         skb->priority = RX_PROTOCOL_ERROR;
1192 post_abort:
1193         skb->mark = RXRPC_SKB_MARK_LOCAL_ABORT;
1194 reject_packet:
1195         trace_rxrpc_rx_done(skb->mark, skb->priority);
1196         rxrpc_reject_packet(local, skb);
1197         _leave(" [badmsg]");
1198 }