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a95d25dd7b
The call state may be changed at any time by the data-ready routine in
response to received packets, so if the call state is to be read and acted
upon several times in a function, READ_ONCE() must be used unless the call
state lock is held.
As it happens, we used READ_ONCE() to read the state a few lines above the
unmarked read in rxrpc_input_data(), so use that value rather than
re-reading it.
Fixes: a158bdd324
("rxrpc: Fix call timeouts")
Signed-off-by: Baptiste Lepers <baptiste.lepers@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/161046715522.2450566.488819910256264150.stgit@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
1469 lines
38 KiB
C
1469 lines
38 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/* RxRPC packet reception
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*
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* Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/module.h>
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#include <linux/net.h>
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#include <linux/skbuff.h>
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#include <linux/errqueue.h>
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#include <linux/udp.h>
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#include <linux/in.h>
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#include <linux/in6.h>
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#include <linux/icmp.h>
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#include <linux/gfp.h>
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#include <net/sock.h>
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#include <net/af_rxrpc.h>
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#include <net/ip.h>
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#include <net/udp.h>
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#include <net/net_namespace.h>
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#include "ar-internal.h"
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static void rxrpc_proto_abort(const char *why,
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struct rxrpc_call *call, rxrpc_seq_t seq)
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{
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if (rxrpc_abort_call(why, call, seq, RX_PROTOCOL_ERROR, -EBADMSG)) {
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set_bit(RXRPC_CALL_EV_ABORT, &call->events);
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rxrpc_queue_call(call);
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}
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}
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/*
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* Do TCP-style congestion management [RFC 5681].
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*/
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static void rxrpc_congestion_management(struct rxrpc_call *call,
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struct sk_buff *skb,
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struct rxrpc_ack_summary *summary,
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rxrpc_serial_t acked_serial)
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{
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enum rxrpc_congest_change change = rxrpc_cong_no_change;
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unsigned int cumulative_acks = call->cong_cumul_acks;
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unsigned int cwnd = call->cong_cwnd;
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bool resend = false;
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summary->flight_size =
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(call->tx_top - call->tx_hard_ack) - summary->nr_acks;
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if (test_and_clear_bit(RXRPC_CALL_RETRANS_TIMEOUT, &call->flags)) {
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summary->retrans_timeo = true;
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call->cong_ssthresh = max_t(unsigned int,
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summary->flight_size / 2, 2);
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cwnd = 1;
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if (cwnd >= call->cong_ssthresh &&
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call->cong_mode == RXRPC_CALL_SLOW_START) {
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call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
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call->cong_tstamp = skb->tstamp;
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cumulative_acks = 0;
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}
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}
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cumulative_acks += summary->nr_new_acks;
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cumulative_acks += summary->nr_rot_new_acks;
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if (cumulative_acks > 255)
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cumulative_acks = 255;
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summary->mode = call->cong_mode;
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summary->cwnd = call->cong_cwnd;
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summary->ssthresh = call->cong_ssthresh;
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summary->cumulative_acks = cumulative_acks;
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summary->dup_acks = call->cong_dup_acks;
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switch (call->cong_mode) {
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case RXRPC_CALL_SLOW_START:
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if (summary->nr_nacks > 0)
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goto packet_loss_detected;
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if (summary->cumulative_acks > 0)
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cwnd += 1;
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if (cwnd >= call->cong_ssthresh) {
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call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
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call->cong_tstamp = skb->tstamp;
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}
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goto out;
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case RXRPC_CALL_CONGEST_AVOIDANCE:
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if (summary->nr_nacks > 0)
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goto packet_loss_detected;
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/* We analyse the number of packets that get ACK'd per RTT
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* period and increase the window if we managed to fill it.
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*/
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if (call->peer->rtt_count == 0)
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goto out;
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if (ktime_before(skb->tstamp,
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ktime_add_us(call->cong_tstamp,
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call->peer->srtt_us >> 3)))
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goto out_no_clear_ca;
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change = rxrpc_cong_rtt_window_end;
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call->cong_tstamp = skb->tstamp;
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if (cumulative_acks >= cwnd)
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cwnd++;
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goto out;
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case RXRPC_CALL_PACKET_LOSS:
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if (summary->nr_nacks == 0)
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goto resume_normality;
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if (summary->new_low_nack) {
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change = rxrpc_cong_new_low_nack;
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call->cong_dup_acks = 1;
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if (call->cong_extra > 1)
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call->cong_extra = 1;
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goto send_extra_data;
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}
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call->cong_dup_acks++;
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if (call->cong_dup_acks < 3)
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goto send_extra_data;
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change = rxrpc_cong_begin_retransmission;
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call->cong_mode = RXRPC_CALL_FAST_RETRANSMIT;
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call->cong_ssthresh = max_t(unsigned int,
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summary->flight_size / 2, 2);
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cwnd = call->cong_ssthresh + 3;
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call->cong_extra = 0;
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call->cong_dup_acks = 0;
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resend = true;
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goto out;
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case RXRPC_CALL_FAST_RETRANSMIT:
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if (!summary->new_low_nack) {
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if (summary->nr_new_acks == 0)
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cwnd += 1;
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call->cong_dup_acks++;
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if (call->cong_dup_acks == 2) {
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change = rxrpc_cong_retransmit_again;
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call->cong_dup_acks = 0;
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resend = true;
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}
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} else {
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change = rxrpc_cong_progress;
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cwnd = call->cong_ssthresh;
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if (summary->nr_nacks == 0)
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goto resume_normality;
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}
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goto out;
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default:
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BUG();
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goto out;
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}
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resume_normality:
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change = rxrpc_cong_cleared_nacks;
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call->cong_dup_acks = 0;
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call->cong_extra = 0;
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call->cong_tstamp = skb->tstamp;
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if (cwnd < call->cong_ssthresh)
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call->cong_mode = RXRPC_CALL_SLOW_START;
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else
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call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
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out:
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cumulative_acks = 0;
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out_no_clear_ca:
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if (cwnd >= RXRPC_RXTX_BUFF_SIZE - 1)
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cwnd = RXRPC_RXTX_BUFF_SIZE - 1;
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call->cong_cwnd = cwnd;
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call->cong_cumul_acks = cumulative_acks;
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trace_rxrpc_congest(call, summary, acked_serial, change);
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if (resend && !test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
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rxrpc_queue_call(call);
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return;
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packet_loss_detected:
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change = rxrpc_cong_saw_nack;
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call->cong_mode = RXRPC_CALL_PACKET_LOSS;
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call->cong_dup_acks = 0;
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goto send_extra_data;
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send_extra_data:
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/* Send some previously unsent DATA if we have some to advance the ACK
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* state.
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*/
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if (call->rxtx_annotations[call->tx_top & RXRPC_RXTX_BUFF_MASK] &
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RXRPC_TX_ANNO_LAST ||
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summary->nr_acks != call->tx_top - call->tx_hard_ack) {
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call->cong_extra++;
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wake_up(&call->waitq);
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}
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goto out_no_clear_ca;
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}
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/*
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* Apply a hard ACK by advancing the Tx window.
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*/
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static bool rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to,
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struct rxrpc_ack_summary *summary)
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{
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struct sk_buff *skb, *list = NULL;
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bool rot_last = false;
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int ix;
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u8 annotation;
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if (call->acks_lowest_nak == call->tx_hard_ack) {
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call->acks_lowest_nak = to;
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} else if (before_eq(call->acks_lowest_nak, to)) {
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summary->new_low_nack = true;
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call->acks_lowest_nak = to;
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}
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spin_lock(&call->lock);
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while (before(call->tx_hard_ack, to)) {
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call->tx_hard_ack++;
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ix = call->tx_hard_ack & RXRPC_RXTX_BUFF_MASK;
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skb = call->rxtx_buffer[ix];
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annotation = call->rxtx_annotations[ix];
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rxrpc_see_skb(skb, rxrpc_skb_rotated);
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call->rxtx_buffer[ix] = NULL;
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call->rxtx_annotations[ix] = 0;
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skb->next = list;
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list = skb;
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if (annotation & RXRPC_TX_ANNO_LAST) {
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set_bit(RXRPC_CALL_TX_LAST, &call->flags);
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rot_last = true;
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}
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if ((annotation & RXRPC_TX_ANNO_MASK) != RXRPC_TX_ANNO_ACK)
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summary->nr_rot_new_acks++;
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}
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spin_unlock(&call->lock);
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trace_rxrpc_transmit(call, (rot_last ?
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rxrpc_transmit_rotate_last :
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rxrpc_transmit_rotate));
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wake_up(&call->waitq);
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while (list) {
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skb = list;
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list = skb->next;
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skb_mark_not_on_list(skb);
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rxrpc_free_skb(skb, rxrpc_skb_freed);
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}
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return rot_last;
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}
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/*
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* End the transmission phase of a call.
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*
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* This occurs when we get an ACKALL packet, the first DATA packet of a reply,
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* or a final ACK packet.
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*/
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static bool rxrpc_end_tx_phase(struct rxrpc_call *call, bool reply_begun,
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const char *abort_why)
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{
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unsigned int state;
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ASSERT(test_bit(RXRPC_CALL_TX_LAST, &call->flags));
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write_lock(&call->state_lock);
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state = call->state;
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switch (state) {
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case RXRPC_CALL_CLIENT_SEND_REQUEST:
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case RXRPC_CALL_CLIENT_AWAIT_REPLY:
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if (reply_begun)
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call->state = state = RXRPC_CALL_CLIENT_RECV_REPLY;
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else
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call->state = state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
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break;
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case RXRPC_CALL_SERVER_AWAIT_ACK:
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__rxrpc_call_completed(call);
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state = call->state;
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break;
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default:
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goto bad_state;
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}
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write_unlock(&call->state_lock);
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if (state == RXRPC_CALL_CLIENT_AWAIT_REPLY)
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trace_rxrpc_transmit(call, rxrpc_transmit_await_reply);
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else
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trace_rxrpc_transmit(call, rxrpc_transmit_end);
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_leave(" = ok");
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return true;
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bad_state:
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write_unlock(&call->state_lock);
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kdebug("end_tx %s", rxrpc_call_states[call->state]);
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rxrpc_proto_abort(abort_why, call, call->tx_top);
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return false;
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}
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/*
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* Begin the reply reception phase of a call.
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*/
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static bool rxrpc_receiving_reply(struct rxrpc_call *call)
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{
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struct rxrpc_ack_summary summary = { 0 };
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unsigned long now, timo;
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rxrpc_seq_t top = READ_ONCE(call->tx_top);
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if (call->ackr_reason) {
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spin_lock_bh(&call->lock);
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call->ackr_reason = 0;
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spin_unlock_bh(&call->lock);
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now = jiffies;
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timo = now + MAX_JIFFY_OFFSET;
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WRITE_ONCE(call->resend_at, timo);
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WRITE_ONCE(call->ack_at, timo);
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trace_rxrpc_timer(call, rxrpc_timer_init_for_reply, now);
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}
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if (!test_bit(RXRPC_CALL_TX_LAST, &call->flags)) {
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if (!rxrpc_rotate_tx_window(call, top, &summary)) {
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rxrpc_proto_abort("TXL", call, top);
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return false;
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}
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}
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if (!rxrpc_end_tx_phase(call, true, "ETD"))
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return false;
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call->tx_phase = false;
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return true;
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}
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|
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/*
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* Scan a data packet to validate its structure and to work out how many
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* subpackets it contains.
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*
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* A jumbo packet is a collection of consecutive packets glued together with
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* little headers between that indicate how to change the initial header for
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* each subpacket.
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*
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* RXRPC_JUMBO_PACKET must be set on all but the last subpacket - and all but
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* the last are RXRPC_JUMBO_DATALEN in size. The last subpacket may be of any
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* size.
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*/
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static bool rxrpc_validate_data(struct sk_buff *skb)
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{
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struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
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unsigned int offset = sizeof(struct rxrpc_wire_header);
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unsigned int len = skb->len;
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u8 flags = sp->hdr.flags;
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for (;;) {
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if (flags & RXRPC_REQUEST_ACK)
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__set_bit(sp->nr_subpackets, sp->rx_req_ack);
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sp->nr_subpackets++;
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if (!(flags & RXRPC_JUMBO_PACKET))
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break;
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if (len - offset < RXRPC_JUMBO_SUBPKTLEN)
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goto protocol_error;
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if (flags & RXRPC_LAST_PACKET)
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goto protocol_error;
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offset += RXRPC_JUMBO_DATALEN;
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if (skb_copy_bits(skb, offset, &flags, 1) < 0)
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goto protocol_error;
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offset += sizeof(struct rxrpc_jumbo_header);
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}
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if (flags & RXRPC_LAST_PACKET)
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sp->rx_flags |= RXRPC_SKB_INCL_LAST;
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return true;
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|
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protocol_error:
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return false;
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}
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|
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/*
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* Handle reception of a duplicate packet.
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*
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* We have to take care to avoid an attack here whereby we're given a series of
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* jumbograms, each with a sequence number one before the preceding one and
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* filled up to maximum UDP size. If they never send us the first packet in
|
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* the sequence, they can cause us to have to hold on to around 2MiB of kernel
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* space until the call times out.
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*
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* We limit the space usage by only accepting three duplicate jumbo packets per
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* call. After that, we tell the other side we're no longer accepting jumbos
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* (that information is encoded in the ACK packet).
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*/
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static void rxrpc_input_dup_data(struct rxrpc_call *call, rxrpc_seq_t seq,
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bool is_jumbo, bool *_jumbo_bad)
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{
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/* Discard normal packets that are duplicates. */
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if (is_jumbo)
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return;
|
|
|
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/* Skip jumbo subpackets that are duplicates. When we've had three or
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* more partially duplicate jumbo packets, we refuse to take any more
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* jumbos for this call.
|
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*/
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if (!*_jumbo_bad) {
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call->nr_jumbo_bad++;
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*_jumbo_bad = true;
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}
|
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}
|
|
|
|
/*
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* Process a DATA packet, adding the packet to the Rx ring. The caller's
|
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* packet ref must be passed on or discarded.
|
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*/
|
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static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
|
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{
|
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struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
|
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enum rxrpc_call_state state;
|
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unsigned int j, nr_subpackets;
|
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rxrpc_serial_t serial = sp->hdr.serial, ack_serial = 0;
|
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rxrpc_seq_t seq0 = sp->hdr.seq, hard_ack;
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bool immediate_ack = false, jumbo_bad = false;
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u8 ack = 0;
|
|
|
|
_enter("{%u,%u},{%u,%u}",
|
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call->rx_hard_ack, call->rx_top, skb->len, seq0);
|
|
|
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_proto("Rx DATA %%%u { #%u f=%02x n=%u }",
|
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sp->hdr.serial, seq0, sp->hdr.flags, sp->nr_subpackets);
|
|
|
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state = READ_ONCE(call->state);
|
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if (state >= RXRPC_CALL_COMPLETE) {
|
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rxrpc_free_skb(skb, rxrpc_skb_freed);
|
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return;
|
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}
|
|
|
|
if (state == RXRPC_CALL_SERVER_RECV_REQUEST) {
|
|
unsigned long timo = READ_ONCE(call->next_req_timo);
|
|
unsigned long now, expect_req_by;
|
|
|
|
if (timo) {
|
|
now = jiffies;
|
|
expect_req_by = now + timo;
|
|
WRITE_ONCE(call->expect_req_by, expect_req_by);
|
|
rxrpc_reduce_call_timer(call, expect_req_by, now,
|
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rxrpc_timer_set_for_idle);
|
|
}
|
|
}
|
|
|
|
spin_lock(&call->input_lock);
|
|
|
|
/* Received data implicitly ACKs all of the request packets we sent
|
|
* when we're acting as a client.
|
|
*/
|
|
if ((state == RXRPC_CALL_CLIENT_SEND_REQUEST ||
|
|
state == RXRPC_CALL_CLIENT_AWAIT_REPLY) &&
|
|
!rxrpc_receiving_reply(call))
|
|
goto unlock;
|
|
|
|
call->ackr_prev_seq = seq0;
|
|
hard_ack = READ_ONCE(call->rx_hard_ack);
|
|
|
|
nr_subpackets = sp->nr_subpackets;
|
|
if (nr_subpackets > 1) {
|
|
if (call->nr_jumbo_bad > 3) {
|
|
ack = RXRPC_ACK_NOSPACE;
|
|
ack_serial = serial;
|
|
goto ack;
|
|
}
|
|
}
|
|
|
|
for (j = 0; j < nr_subpackets; j++) {
|
|
rxrpc_serial_t serial = sp->hdr.serial + j;
|
|
rxrpc_seq_t seq = seq0 + j;
|
|
unsigned int ix = seq & RXRPC_RXTX_BUFF_MASK;
|
|
bool terminal = (j == nr_subpackets - 1);
|
|
bool last = terminal && (sp->rx_flags & RXRPC_SKB_INCL_LAST);
|
|
u8 flags, annotation = j;
|
|
|
|
_proto("Rx DATA+%u %%%u { #%x t=%u l=%u }",
|
|
j, serial, seq, terminal, last);
|
|
|
|
if (last) {
|
|
if (test_bit(RXRPC_CALL_RX_LAST, &call->flags) &&
|
|
seq != call->rx_top) {
|
|
rxrpc_proto_abort("LSN", call, seq);
|
|
goto unlock;
|
|
}
|
|
} else {
|
|
if (test_bit(RXRPC_CALL_RX_LAST, &call->flags) &&
|
|
after_eq(seq, call->rx_top)) {
|
|
rxrpc_proto_abort("LSA", call, seq);
|
|
goto unlock;
|
|
}
|
|
}
|
|
|
|
flags = 0;
|
|
if (last)
|
|
flags |= RXRPC_LAST_PACKET;
|
|
if (!terminal)
|
|
flags |= RXRPC_JUMBO_PACKET;
|
|
if (test_bit(j, sp->rx_req_ack))
|
|
flags |= RXRPC_REQUEST_ACK;
|
|
trace_rxrpc_rx_data(call->debug_id, seq, serial, flags, annotation);
|
|
|
|
if (before_eq(seq, hard_ack)) {
|
|
ack = RXRPC_ACK_DUPLICATE;
|
|
ack_serial = serial;
|
|
continue;
|
|
}
|
|
|
|
if (call->rxtx_buffer[ix]) {
|
|
rxrpc_input_dup_data(call, seq, nr_subpackets > 1,
|
|
&jumbo_bad);
|
|
if (ack != RXRPC_ACK_DUPLICATE) {
|
|
ack = RXRPC_ACK_DUPLICATE;
|
|
ack_serial = serial;
|
|
}
|
|
immediate_ack = true;
|
|
continue;
|
|
}
|
|
|
|
if (after(seq, hard_ack + call->rx_winsize)) {
|
|
ack = RXRPC_ACK_EXCEEDS_WINDOW;
|
|
ack_serial = serial;
|
|
if (flags & RXRPC_JUMBO_PACKET) {
|
|
if (!jumbo_bad) {
|
|
call->nr_jumbo_bad++;
|
|
jumbo_bad = true;
|
|
}
|
|
}
|
|
|
|
goto ack;
|
|
}
|
|
|
|
if (flags & RXRPC_REQUEST_ACK && !ack) {
|
|
ack = RXRPC_ACK_REQUESTED;
|
|
ack_serial = serial;
|
|
}
|
|
|
|
/* Queue the packet. We use a couple of memory barriers here as need
|
|
* to make sure that rx_top is perceived to be set after the buffer
|
|
* pointer and that the buffer pointer is set after the annotation and
|
|
* the skb data.
|
|
*
|
|
* Barriers against rxrpc_recvmsg_data() and rxrpc_rotate_rx_window()
|
|
* and also rxrpc_fill_out_ack().
|
|
*/
|
|
if (!terminal)
|
|
rxrpc_get_skb(skb, rxrpc_skb_got);
|
|
call->rxtx_annotations[ix] = annotation;
|
|
smp_wmb();
|
|
call->rxtx_buffer[ix] = skb;
|
|
if (after(seq, call->rx_top)) {
|
|
smp_store_release(&call->rx_top, seq);
|
|
} else if (before(seq, call->rx_top)) {
|
|
/* Send an immediate ACK if we fill in a hole */
|
|
if (!ack) {
|
|
ack = RXRPC_ACK_DELAY;
|
|
ack_serial = serial;
|
|
}
|
|
immediate_ack = true;
|
|
}
|
|
|
|
if (terminal) {
|
|
/* From this point on, we're not allowed to touch the
|
|
* packet any longer as its ref now belongs to the Rx
|
|
* ring.
|
|
*/
|
|
skb = NULL;
|
|
sp = NULL;
|
|
}
|
|
|
|
if (last) {
|
|
set_bit(RXRPC_CALL_RX_LAST, &call->flags);
|
|
if (!ack) {
|
|
ack = RXRPC_ACK_DELAY;
|
|
ack_serial = serial;
|
|
}
|
|
trace_rxrpc_receive(call, rxrpc_receive_queue_last, serial, seq);
|
|
} else {
|
|
trace_rxrpc_receive(call, rxrpc_receive_queue, serial, seq);
|
|
}
|
|
|
|
if (after_eq(seq, call->rx_expect_next)) {
|
|
if (after(seq, call->rx_expect_next)) {
|
|
_net("OOS %u > %u", seq, call->rx_expect_next);
|
|
ack = RXRPC_ACK_OUT_OF_SEQUENCE;
|
|
ack_serial = serial;
|
|
}
|
|
call->rx_expect_next = seq + 1;
|
|
}
|
|
}
|
|
|
|
ack:
|
|
if (ack)
|
|
rxrpc_propose_ACK(call, ack, ack_serial,
|
|
immediate_ack, true,
|
|
rxrpc_propose_ack_input_data);
|
|
else
|
|
rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, serial,
|
|
false, true,
|
|
rxrpc_propose_ack_input_data);
|
|
|
|
trace_rxrpc_notify_socket(call->debug_id, serial);
|
|
rxrpc_notify_socket(call);
|
|
|
|
unlock:
|
|
spin_unlock(&call->input_lock);
|
|
rxrpc_free_skb(skb, rxrpc_skb_freed);
|
|
_leave(" [queued]");
|
|
}
|
|
|
|
/*
|
|
* See if there's a cached RTT probe to complete.
|
|
*/
|
|
static void rxrpc_complete_rtt_probe(struct rxrpc_call *call,
|
|
ktime_t resp_time,
|
|
rxrpc_serial_t acked_serial,
|
|
rxrpc_serial_t ack_serial,
|
|
enum rxrpc_rtt_rx_trace type)
|
|
{
|
|
rxrpc_serial_t orig_serial;
|
|
unsigned long avail;
|
|
ktime_t sent_at;
|
|
bool matched = false;
|
|
int i;
|
|
|
|
avail = READ_ONCE(call->rtt_avail);
|
|
smp_rmb(); /* Read avail bits before accessing data. */
|
|
|
|
for (i = 0; i < ARRAY_SIZE(call->rtt_serial); i++) {
|
|
if (!test_bit(i + RXRPC_CALL_RTT_PEND_SHIFT, &avail))
|
|
continue;
|
|
|
|
sent_at = call->rtt_sent_at[i];
|
|
orig_serial = call->rtt_serial[i];
|
|
|
|
if (orig_serial == acked_serial) {
|
|
clear_bit(i + RXRPC_CALL_RTT_PEND_SHIFT, &call->rtt_avail);
|
|
smp_mb(); /* Read data before setting avail bit */
|
|
set_bit(i, &call->rtt_avail);
|
|
if (type != rxrpc_rtt_rx_cancel)
|
|
rxrpc_peer_add_rtt(call, type, i, acked_serial, ack_serial,
|
|
sent_at, resp_time);
|
|
else
|
|
trace_rxrpc_rtt_rx(call, rxrpc_rtt_rx_cancel, i,
|
|
orig_serial, acked_serial, 0, 0);
|
|
matched = true;
|
|
}
|
|
|
|
/* If a later serial is being acked, then mark this slot as
|
|
* being available.
|
|
*/
|
|
if (after(acked_serial, orig_serial)) {
|
|
trace_rxrpc_rtt_rx(call, rxrpc_rtt_rx_obsolete, i,
|
|
orig_serial, acked_serial, 0, 0);
|
|
clear_bit(i + RXRPC_CALL_RTT_PEND_SHIFT, &call->rtt_avail);
|
|
smp_wmb();
|
|
set_bit(i, &call->rtt_avail);
|
|
}
|
|
}
|
|
|
|
if (!matched)
|
|
trace_rxrpc_rtt_rx(call, rxrpc_rtt_rx_lost, 9, 0, acked_serial, 0, 0);
|
|
}
|
|
|
|
/*
|
|
* Process the response to a ping that we sent to find out if we lost an ACK.
|
|
*
|
|
* If we got back a ping response that indicates a lower tx_top than what we
|
|
* had at the time of the ping transmission, we adjudge all the DATA packets
|
|
* sent between the response tx_top and the ping-time tx_top to have been lost.
|
|
*/
|
|
static void rxrpc_input_check_for_lost_ack(struct rxrpc_call *call)
|
|
{
|
|
rxrpc_seq_t top, bottom, seq;
|
|
bool resend = false;
|
|
|
|
spin_lock_bh(&call->lock);
|
|
|
|
bottom = call->tx_hard_ack + 1;
|
|
top = call->acks_lost_top;
|
|
if (before(bottom, top)) {
|
|
for (seq = bottom; before_eq(seq, top); seq++) {
|
|
int ix = seq & RXRPC_RXTX_BUFF_MASK;
|
|
u8 annotation = call->rxtx_annotations[ix];
|
|
u8 anno_type = annotation & RXRPC_TX_ANNO_MASK;
|
|
|
|
if (anno_type != RXRPC_TX_ANNO_UNACK)
|
|
continue;
|
|
annotation &= ~RXRPC_TX_ANNO_MASK;
|
|
annotation |= RXRPC_TX_ANNO_RETRANS;
|
|
call->rxtx_annotations[ix] = annotation;
|
|
resend = true;
|
|
}
|
|
}
|
|
|
|
spin_unlock_bh(&call->lock);
|
|
|
|
if (resend && !test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
|
|
rxrpc_queue_call(call);
|
|
}
|
|
|
|
/*
|
|
* Process a ping response.
|
|
*/
|
|
static void rxrpc_input_ping_response(struct rxrpc_call *call,
|
|
ktime_t resp_time,
|
|
rxrpc_serial_t acked_serial,
|
|
rxrpc_serial_t ack_serial)
|
|
{
|
|
if (acked_serial == call->acks_lost_ping)
|
|
rxrpc_input_check_for_lost_ack(call);
|
|
}
|
|
|
|
/*
|
|
* Process the extra information that may be appended to an ACK packet
|
|
*/
|
|
static void rxrpc_input_ackinfo(struct rxrpc_call *call, struct sk_buff *skb,
|
|
struct rxrpc_ackinfo *ackinfo)
|
|
{
|
|
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
|
|
struct rxrpc_peer *peer;
|
|
unsigned int mtu;
|
|
bool wake = false;
|
|
u32 rwind = ntohl(ackinfo->rwind);
|
|
|
|
_proto("Rx ACK %%%u Info { rx=%u max=%u rwin=%u jm=%u }",
|
|
sp->hdr.serial,
|
|
ntohl(ackinfo->rxMTU), ntohl(ackinfo->maxMTU),
|
|
rwind, ntohl(ackinfo->jumbo_max));
|
|
|
|
if (rwind > RXRPC_RXTX_BUFF_SIZE - 1)
|
|
rwind = RXRPC_RXTX_BUFF_SIZE - 1;
|
|
if (call->tx_winsize != rwind) {
|
|
if (rwind > call->tx_winsize)
|
|
wake = true;
|
|
trace_rxrpc_rx_rwind_change(call, sp->hdr.serial, rwind, wake);
|
|
call->tx_winsize = rwind;
|
|
}
|
|
|
|
if (call->cong_ssthresh > rwind)
|
|
call->cong_ssthresh = rwind;
|
|
|
|
mtu = min(ntohl(ackinfo->rxMTU), ntohl(ackinfo->maxMTU));
|
|
|
|
peer = call->peer;
|
|
if (mtu < peer->maxdata) {
|
|
spin_lock_bh(&peer->lock);
|
|
peer->maxdata = mtu;
|
|
peer->mtu = mtu + peer->hdrsize;
|
|
spin_unlock_bh(&peer->lock);
|
|
_net("Net MTU %u (maxdata %u)", peer->mtu, peer->maxdata);
|
|
}
|
|
|
|
if (wake)
|
|
wake_up(&call->waitq);
|
|
}
|
|
|
|
/*
|
|
* Process individual soft ACKs.
|
|
*
|
|
* Each ACK in the array corresponds to one packet and can be either an ACK or
|
|
* a NAK. If we get find an explicitly NAK'd packet we resend immediately;
|
|
* packets that lie beyond the end of the ACK list are scheduled for resend by
|
|
* the timer on the basis that the peer might just not have processed them at
|
|
* the time the ACK was sent.
|
|
*/
|
|
static void rxrpc_input_soft_acks(struct rxrpc_call *call, u8 *acks,
|
|
rxrpc_seq_t seq, int nr_acks,
|
|
struct rxrpc_ack_summary *summary)
|
|
{
|
|
int ix;
|
|
u8 annotation, anno_type;
|
|
|
|
for (; nr_acks > 0; nr_acks--, seq++) {
|
|
ix = seq & RXRPC_RXTX_BUFF_MASK;
|
|
annotation = call->rxtx_annotations[ix];
|
|
anno_type = annotation & RXRPC_TX_ANNO_MASK;
|
|
annotation &= ~RXRPC_TX_ANNO_MASK;
|
|
switch (*acks++) {
|
|
case RXRPC_ACK_TYPE_ACK:
|
|
summary->nr_acks++;
|
|
if (anno_type == RXRPC_TX_ANNO_ACK)
|
|
continue;
|
|
summary->nr_new_acks++;
|
|
call->rxtx_annotations[ix] =
|
|
RXRPC_TX_ANNO_ACK | annotation;
|
|
break;
|
|
case RXRPC_ACK_TYPE_NACK:
|
|
if (!summary->nr_nacks &&
|
|
call->acks_lowest_nak != seq) {
|
|
call->acks_lowest_nak = seq;
|
|
summary->new_low_nack = true;
|
|
}
|
|
summary->nr_nacks++;
|
|
if (anno_type == RXRPC_TX_ANNO_NAK)
|
|
continue;
|
|
summary->nr_new_nacks++;
|
|
if (anno_type == RXRPC_TX_ANNO_RETRANS)
|
|
continue;
|
|
call->rxtx_annotations[ix] =
|
|
RXRPC_TX_ANNO_NAK | annotation;
|
|
break;
|
|
default:
|
|
return rxrpc_proto_abort("SFT", call, 0);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Return true if the ACK is valid - ie. it doesn't appear to have regressed
|
|
* with respect to the ack state conveyed by preceding ACKs.
|
|
*/
|
|
static bool rxrpc_is_ack_valid(struct rxrpc_call *call,
|
|
rxrpc_seq_t first_pkt, rxrpc_seq_t prev_pkt)
|
|
{
|
|
rxrpc_seq_t base = READ_ONCE(call->ackr_first_seq);
|
|
|
|
if (after(first_pkt, base))
|
|
return true; /* The window advanced */
|
|
|
|
if (before(first_pkt, base))
|
|
return false; /* firstPacket regressed */
|
|
|
|
if (after_eq(prev_pkt, call->ackr_prev_seq))
|
|
return true; /* previousPacket hasn't regressed. */
|
|
|
|
/* Some rx implementations put a serial number in previousPacket. */
|
|
if (after_eq(prev_pkt, base + call->tx_winsize))
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Process an ACK packet.
|
|
*
|
|
* ack.firstPacket is the sequence number of the first soft-ACK'd/NAK'd packet
|
|
* in the ACK array. Anything before that is hard-ACK'd and may be discarded.
|
|
*
|
|
* A hard-ACK means that a packet has been processed and may be discarded; a
|
|
* soft-ACK means that the packet may be discarded and retransmission
|
|
* requested. A phase is complete when all packets are hard-ACK'd.
|
|
*/
|
|
static void rxrpc_input_ack(struct rxrpc_call *call, struct sk_buff *skb)
|
|
{
|
|
struct rxrpc_ack_summary summary = { 0 };
|
|
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
|
|
union {
|
|
struct rxrpc_ackpacket ack;
|
|
struct rxrpc_ackinfo info;
|
|
u8 acks[RXRPC_MAXACKS];
|
|
} buf;
|
|
rxrpc_serial_t ack_serial, acked_serial;
|
|
rxrpc_seq_t first_soft_ack, hard_ack, prev_pkt;
|
|
int nr_acks, offset, ioffset;
|
|
|
|
_enter("");
|
|
|
|
offset = sizeof(struct rxrpc_wire_header);
|
|
if (skb_copy_bits(skb, offset, &buf.ack, sizeof(buf.ack)) < 0) {
|
|
_debug("extraction failure");
|
|
return rxrpc_proto_abort("XAK", call, 0);
|
|
}
|
|
offset += sizeof(buf.ack);
|
|
|
|
ack_serial = sp->hdr.serial;
|
|
acked_serial = ntohl(buf.ack.serial);
|
|
first_soft_ack = ntohl(buf.ack.firstPacket);
|
|
prev_pkt = ntohl(buf.ack.previousPacket);
|
|
hard_ack = first_soft_ack - 1;
|
|
nr_acks = buf.ack.nAcks;
|
|
summary.ack_reason = (buf.ack.reason < RXRPC_ACK__INVALID ?
|
|
buf.ack.reason : RXRPC_ACK__INVALID);
|
|
|
|
trace_rxrpc_rx_ack(call, ack_serial, acked_serial,
|
|
first_soft_ack, prev_pkt,
|
|
summary.ack_reason, nr_acks);
|
|
|
|
switch (buf.ack.reason) {
|
|
case RXRPC_ACK_PING_RESPONSE:
|
|
rxrpc_input_ping_response(call, skb->tstamp, acked_serial,
|
|
ack_serial);
|
|
rxrpc_complete_rtt_probe(call, skb->tstamp, acked_serial, ack_serial,
|
|
rxrpc_rtt_rx_ping_response);
|
|
break;
|
|
case RXRPC_ACK_REQUESTED:
|
|
rxrpc_complete_rtt_probe(call, skb->tstamp, acked_serial, ack_serial,
|
|
rxrpc_rtt_rx_requested_ack);
|
|
break;
|
|
default:
|
|
if (acked_serial != 0)
|
|
rxrpc_complete_rtt_probe(call, skb->tstamp, acked_serial, ack_serial,
|
|
rxrpc_rtt_rx_cancel);
|
|
break;
|
|
}
|
|
|
|
if (buf.ack.reason == RXRPC_ACK_PING) {
|
|
_proto("Rx ACK %%%u PING Request", ack_serial);
|
|
rxrpc_propose_ACK(call, RXRPC_ACK_PING_RESPONSE,
|
|
ack_serial, true, true,
|
|
rxrpc_propose_ack_respond_to_ping);
|
|
} else if (sp->hdr.flags & RXRPC_REQUEST_ACK) {
|
|
rxrpc_propose_ACK(call, RXRPC_ACK_REQUESTED,
|
|
ack_serial, true, true,
|
|
rxrpc_propose_ack_respond_to_ack);
|
|
}
|
|
|
|
/* Discard any out-of-order or duplicate ACKs (outside lock). */
|
|
if (!rxrpc_is_ack_valid(call, first_soft_ack, prev_pkt)) {
|
|
trace_rxrpc_rx_discard_ack(call->debug_id, ack_serial,
|
|
first_soft_ack, call->ackr_first_seq,
|
|
prev_pkt, call->ackr_prev_seq);
|
|
return;
|
|
}
|
|
|
|
buf.info.rxMTU = 0;
|
|
ioffset = offset + nr_acks + 3;
|
|
if (skb->len >= ioffset + sizeof(buf.info) &&
|
|
skb_copy_bits(skb, ioffset, &buf.info, sizeof(buf.info)) < 0)
|
|
return rxrpc_proto_abort("XAI", call, 0);
|
|
|
|
spin_lock(&call->input_lock);
|
|
|
|
/* Discard any out-of-order or duplicate ACKs (inside lock). */
|
|
if (!rxrpc_is_ack_valid(call, first_soft_ack, prev_pkt)) {
|
|
trace_rxrpc_rx_discard_ack(call->debug_id, ack_serial,
|
|
first_soft_ack, call->ackr_first_seq,
|
|
prev_pkt, call->ackr_prev_seq);
|
|
goto out;
|
|
}
|
|
call->acks_latest_ts = skb->tstamp;
|
|
|
|
call->ackr_first_seq = first_soft_ack;
|
|
call->ackr_prev_seq = prev_pkt;
|
|
|
|
/* Parse rwind and mtu sizes if provided. */
|
|
if (buf.info.rxMTU)
|
|
rxrpc_input_ackinfo(call, skb, &buf.info);
|
|
|
|
if (first_soft_ack == 0) {
|
|
rxrpc_proto_abort("AK0", call, 0);
|
|
goto out;
|
|
}
|
|
|
|
/* Ignore ACKs unless we are or have just been transmitting. */
|
|
switch (READ_ONCE(call->state)) {
|
|
case RXRPC_CALL_CLIENT_SEND_REQUEST:
|
|
case RXRPC_CALL_CLIENT_AWAIT_REPLY:
|
|
case RXRPC_CALL_SERVER_SEND_REPLY:
|
|
case RXRPC_CALL_SERVER_AWAIT_ACK:
|
|
break;
|
|
default:
|
|
goto out;
|
|
}
|
|
|
|
if (before(hard_ack, call->tx_hard_ack) ||
|
|
after(hard_ack, call->tx_top)) {
|
|
rxrpc_proto_abort("AKW", call, 0);
|
|
goto out;
|
|
}
|
|
if (nr_acks > call->tx_top - hard_ack) {
|
|
rxrpc_proto_abort("AKN", call, 0);
|
|
goto out;
|
|
}
|
|
|
|
if (after(hard_ack, call->tx_hard_ack)) {
|
|
if (rxrpc_rotate_tx_window(call, hard_ack, &summary)) {
|
|
rxrpc_end_tx_phase(call, false, "ETA");
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (nr_acks > 0) {
|
|
if (skb_copy_bits(skb, offset, buf.acks, nr_acks) < 0) {
|
|
rxrpc_proto_abort("XSA", call, 0);
|
|
goto out;
|
|
}
|
|
rxrpc_input_soft_acks(call, buf.acks, first_soft_ack, nr_acks,
|
|
&summary);
|
|
}
|
|
|
|
if (call->rxtx_annotations[call->tx_top & RXRPC_RXTX_BUFF_MASK] &
|
|
RXRPC_TX_ANNO_LAST &&
|
|
summary.nr_acks == call->tx_top - hard_ack &&
|
|
rxrpc_is_client_call(call))
|
|
rxrpc_propose_ACK(call, RXRPC_ACK_PING, ack_serial,
|
|
false, true,
|
|
rxrpc_propose_ack_ping_for_lost_reply);
|
|
|
|
rxrpc_congestion_management(call, skb, &summary, acked_serial);
|
|
out:
|
|
spin_unlock(&call->input_lock);
|
|
}
|
|
|
|
/*
|
|
* Process an ACKALL packet.
|
|
*/
|
|
static void rxrpc_input_ackall(struct rxrpc_call *call, struct sk_buff *skb)
|
|
{
|
|
struct rxrpc_ack_summary summary = { 0 };
|
|
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
|
|
|
|
_proto("Rx ACKALL %%%u", sp->hdr.serial);
|
|
|
|
spin_lock(&call->input_lock);
|
|
|
|
if (rxrpc_rotate_tx_window(call, call->tx_top, &summary))
|
|
rxrpc_end_tx_phase(call, false, "ETL");
|
|
|
|
spin_unlock(&call->input_lock);
|
|
}
|
|
|
|
/*
|
|
* Process an ABORT packet directed at a call.
|
|
*/
|
|
static void rxrpc_input_abort(struct rxrpc_call *call, struct sk_buff *skb)
|
|
{
|
|
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
|
|
__be32 wtmp;
|
|
u32 abort_code = RX_CALL_DEAD;
|
|
|
|
_enter("");
|
|
|
|
if (skb->len >= 4 &&
|
|
skb_copy_bits(skb, sizeof(struct rxrpc_wire_header),
|
|
&wtmp, sizeof(wtmp)) >= 0)
|
|
abort_code = ntohl(wtmp);
|
|
|
|
trace_rxrpc_rx_abort(call, sp->hdr.serial, abort_code);
|
|
|
|
_proto("Rx ABORT %%%u { %x }", sp->hdr.serial, abort_code);
|
|
|
|
rxrpc_set_call_completion(call, RXRPC_CALL_REMOTELY_ABORTED,
|
|
abort_code, -ECONNABORTED);
|
|
}
|
|
|
|
/*
|
|
* Process an incoming call packet.
|
|
*/
|
|
static void rxrpc_input_call_packet(struct rxrpc_call *call,
|
|
struct sk_buff *skb)
|
|
{
|
|
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
|
|
unsigned long timo;
|
|
|
|
_enter("%p,%p", call, skb);
|
|
|
|
timo = READ_ONCE(call->next_rx_timo);
|
|
if (timo) {
|
|
unsigned long now = jiffies, expect_rx_by;
|
|
|
|
expect_rx_by = now + timo;
|
|
WRITE_ONCE(call->expect_rx_by, expect_rx_by);
|
|
rxrpc_reduce_call_timer(call, expect_rx_by, now,
|
|
rxrpc_timer_set_for_normal);
|
|
}
|
|
|
|
switch (sp->hdr.type) {
|
|
case RXRPC_PACKET_TYPE_DATA:
|
|
rxrpc_input_data(call, skb);
|
|
goto no_free;
|
|
|
|
case RXRPC_PACKET_TYPE_ACK:
|
|
rxrpc_input_ack(call, skb);
|
|
break;
|
|
|
|
case RXRPC_PACKET_TYPE_BUSY:
|
|
_proto("Rx BUSY %%%u", sp->hdr.serial);
|
|
|
|
/* Just ignore BUSY packets from the server; the retry and
|
|
* lifespan timers will take care of business. BUSY packets
|
|
* from the client don't make sense.
|
|
*/
|
|
break;
|
|
|
|
case RXRPC_PACKET_TYPE_ABORT:
|
|
rxrpc_input_abort(call, skb);
|
|
break;
|
|
|
|
case RXRPC_PACKET_TYPE_ACKALL:
|
|
rxrpc_input_ackall(call, skb);
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
|
|
rxrpc_free_skb(skb, rxrpc_skb_freed);
|
|
no_free:
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* Handle a new service call on a channel implicitly completing the preceding
|
|
* call on that channel. This does not apply to client conns.
|
|
*
|
|
* TODO: If callNumber > call_id + 1, renegotiate security.
|
|
*/
|
|
static void rxrpc_input_implicit_end_call(struct rxrpc_sock *rx,
|
|
struct rxrpc_connection *conn,
|
|
struct rxrpc_call *call)
|
|
{
|
|
switch (READ_ONCE(call->state)) {
|
|
case RXRPC_CALL_SERVER_AWAIT_ACK:
|
|
rxrpc_call_completed(call);
|
|
fallthrough;
|
|
case RXRPC_CALL_COMPLETE:
|
|
break;
|
|
default:
|
|
if (rxrpc_abort_call("IMP", call, 0, RX_CALL_DEAD, -ESHUTDOWN)) {
|
|
set_bit(RXRPC_CALL_EV_ABORT, &call->events);
|
|
rxrpc_queue_call(call);
|
|
}
|
|
trace_rxrpc_improper_term(call);
|
|
break;
|
|
}
|
|
|
|
spin_lock(&rx->incoming_lock);
|
|
__rxrpc_disconnect_call(conn, call);
|
|
spin_unlock(&rx->incoming_lock);
|
|
}
|
|
|
|
/*
|
|
* post connection-level events to the connection
|
|
* - this includes challenges, responses, some aborts and call terminal packet
|
|
* retransmission.
|
|
*/
|
|
static void rxrpc_post_packet_to_conn(struct rxrpc_connection *conn,
|
|
struct sk_buff *skb)
|
|
{
|
|
_enter("%p,%p", conn, skb);
|
|
|
|
skb_queue_tail(&conn->rx_queue, skb);
|
|
rxrpc_queue_conn(conn);
|
|
}
|
|
|
|
/*
|
|
* post endpoint-level events to the local endpoint
|
|
* - this includes debug and version messages
|
|
*/
|
|
static void rxrpc_post_packet_to_local(struct rxrpc_local *local,
|
|
struct sk_buff *skb)
|
|
{
|
|
_enter("%p,%p", local, skb);
|
|
|
|
if (rxrpc_get_local_maybe(local)) {
|
|
skb_queue_tail(&local->event_queue, skb);
|
|
rxrpc_queue_local(local);
|
|
} else {
|
|
rxrpc_free_skb(skb, rxrpc_skb_freed);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* put a packet up for transport-level abort
|
|
*/
|
|
static void rxrpc_reject_packet(struct rxrpc_local *local, struct sk_buff *skb)
|
|
{
|
|
CHECK_SLAB_OKAY(&local->usage);
|
|
|
|
if (rxrpc_get_local_maybe(local)) {
|
|
skb_queue_tail(&local->reject_queue, skb);
|
|
rxrpc_queue_local(local);
|
|
} else {
|
|
rxrpc_free_skb(skb, rxrpc_skb_freed);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Extract the wire header from a packet and translate the byte order.
|
|
*/
|
|
static noinline
|
|
int rxrpc_extract_header(struct rxrpc_skb_priv *sp, struct sk_buff *skb)
|
|
{
|
|
struct rxrpc_wire_header whdr;
|
|
|
|
/* dig out the RxRPC connection details */
|
|
if (skb_copy_bits(skb, 0, &whdr, sizeof(whdr)) < 0) {
|
|
trace_rxrpc_rx_eproto(NULL, sp->hdr.serial,
|
|
tracepoint_string("bad_hdr"));
|
|
return -EBADMSG;
|
|
}
|
|
|
|
memset(sp, 0, sizeof(*sp));
|
|
sp->hdr.epoch = ntohl(whdr.epoch);
|
|
sp->hdr.cid = ntohl(whdr.cid);
|
|
sp->hdr.callNumber = ntohl(whdr.callNumber);
|
|
sp->hdr.seq = ntohl(whdr.seq);
|
|
sp->hdr.serial = ntohl(whdr.serial);
|
|
sp->hdr.flags = whdr.flags;
|
|
sp->hdr.type = whdr.type;
|
|
sp->hdr.userStatus = whdr.userStatus;
|
|
sp->hdr.securityIndex = whdr.securityIndex;
|
|
sp->hdr._rsvd = ntohs(whdr._rsvd);
|
|
sp->hdr.serviceId = ntohs(whdr.serviceId);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* handle data received on the local endpoint
|
|
* - may be called in interrupt context
|
|
*
|
|
* [!] Note that as this is called from the encap_rcv hook, the socket is not
|
|
* held locked by the caller and nothing prevents sk_user_data on the UDP from
|
|
* being cleared in the middle of processing this function.
|
|
*
|
|
* Called with the RCU read lock held from the IP layer via UDP.
|
|
*/
|
|
int rxrpc_input_packet(struct sock *udp_sk, struct sk_buff *skb)
|
|
{
|
|
struct rxrpc_local *local = rcu_dereference_sk_user_data(udp_sk);
|
|
struct rxrpc_connection *conn;
|
|
struct rxrpc_channel *chan;
|
|
struct rxrpc_call *call = NULL;
|
|
struct rxrpc_skb_priv *sp;
|
|
struct rxrpc_peer *peer = NULL;
|
|
struct rxrpc_sock *rx = NULL;
|
|
unsigned int channel;
|
|
|
|
_enter("%p", udp_sk);
|
|
|
|
if (unlikely(!local)) {
|
|
kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
if (skb->tstamp == 0)
|
|
skb->tstamp = ktime_get_real();
|
|
|
|
rxrpc_new_skb(skb, rxrpc_skb_received);
|
|
|
|
skb_pull(skb, sizeof(struct udphdr));
|
|
|
|
/* The UDP protocol already released all skb resources;
|
|
* we are free to add our own data there.
|
|
*/
|
|
sp = rxrpc_skb(skb);
|
|
|
|
/* dig out the RxRPC connection details */
|
|
if (rxrpc_extract_header(sp, skb) < 0)
|
|
goto bad_message;
|
|
|
|
if (IS_ENABLED(CONFIG_AF_RXRPC_INJECT_LOSS)) {
|
|
static int lose;
|
|
if ((lose++ & 7) == 7) {
|
|
trace_rxrpc_rx_lose(sp);
|
|
rxrpc_free_skb(skb, rxrpc_skb_lost);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
if (skb->tstamp == 0)
|
|
skb->tstamp = ktime_get_real();
|
|
trace_rxrpc_rx_packet(sp);
|
|
|
|
switch (sp->hdr.type) {
|
|
case RXRPC_PACKET_TYPE_VERSION:
|
|
if (rxrpc_to_client(sp))
|
|
goto discard;
|
|
rxrpc_post_packet_to_local(local, skb);
|
|
goto out;
|
|
|
|
case RXRPC_PACKET_TYPE_BUSY:
|
|
if (rxrpc_to_server(sp))
|
|
goto discard;
|
|
fallthrough;
|
|
case RXRPC_PACKET_TYPE_ACK:
|
|
case RXRPC_PACKET_TYPE_ACKALL:
|
|
if (sp->hdr.callNumber == 0)
|
|
goto bad_message;
|
|
fallthrough;
|
|
case RXRPC_PACKET_TYPE_ABORT:
|
|
break;
|
|
|
|
case RXRPC_PACKET_TYPE_DATA:
|
|
if (sp->hdr.callNumber == 0 ||
|
|
sp->hdr.seq == 0)
|
|
goto bad_message;
|
|
if (!rxrpc_validate_data(skb))
|
|
goto bad_message;
|
|
|
|
/* Unshare the packet so that it can be modified for in-place
|
|
* decryption.
|
|
*/
|
|
if (sp->hdr.securityIndex != 0) {
|
|
struct sk_buff *nskb = skb_unshare(skb, GFP_ATOMIC);
|
|
if (!nskb) {
|
|
rxrpc_eaten_skb(skb, rxrpc_skb_unshared_nomem);
|
|
goto out;
|
|
}
|
|
|
|
if (nskb != skb) {
|
|
rxrpc_eaten_skb(skb, rxrpc_skb_received);
|
|
skb = nskb;
|
|
rxrpc_new_skb(skb, rxrpc_skb_unshared);
|
|
sp = rxrpc_skb(skb);
|
|
}
|
|
}
|
|
break;
|
|
|
|
case RXRPC_PACKET_TYPE_CHALLENGE:
|
|
if (rxrpc_to_server(sp))
|
|
goto discard;
|
|
break;
|
|
case RXRPC_PACKET_TYPE_RESPONSE:
|
|
if (rxrpc_to_client(sp))
|
|
goto discard;
|
|
break;
|
|
|
|
/* Packet types 9-11 should just be ignored. */
|
|
case RXRPC_PACKET_TYPE_PARAMS:
|
|
case RXRPC_PACKET_TYPE_10:
|
|
case RXRPC_PACKET_TYPE_11:
|
|
goto discard;
|
|
|
|
default:
|
|
_proto("Rx Bad Packet Type %u", sp->hdr.type);
|
|
goto bad_message;
|
|
}
|
|
|
|
if (sp->hdr.serviceId == 0)
|
|
goto bad_message;
|
|
|
|
if (rxrpc_to_server(sp)) {
|
|
/* Weed out packets to services we're not offering. Packets
|
|
* that would begin a call are explicitly rejected and the rest
|
|
* are just discarded.
|
|
*/
|
|
rx = rcu_dereference(local->service);
|
|
if (!rx || (sp->hdr.serviceId != rx->srx.srx_service &&
|
|
sp->hdr.serviceId != rx->second_service)) {
|
|
if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
|
|
sp->hdr.seq == 1)
|
|
goto unsupported_service;
|
|
goto discard;
|
|
}
|
|
}
|
|
|
|
conn = rxrpc_find_connection_rcu(local, skb, &peer);
|
|
if (conn) {
|
|
if (sp->hdr.securityIndex != conn->security_ix)
|
|
goto wrong_security;
|
|
|
|
if (sp->hdr.serviceId != conn->service_id) {
|
|
int old_id;
|
|
|
|
if (!test_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags))
|
|
goto reupgrade;
|
|
old_id = cmpxchg(&conn->service_id, conn->params.service_id,
|
|
sp->hdr.serviceId);
|
|
|
|
if (old_id != conn->params.service_id &&
|
|
old_id != sp->hdr.serviceId)
|
|
goto reupgrade;
|
|
}
|
|
|
|
if (sp->hdr.callNumber == 0) {
|
|
/* Connection-level packet */
|
|
_debug("CONN %p {%d}", conn, conn->debug_id);
|
|
rxrpc_post_packet_to_conn(conn, skb);
|
|
goto out;
|
|
}
|
|
|
|
if ((int)sp->hdr.serial - (int)conn->hi_serial > 0)
|
|
conn->hi_serial = sp->hdr.serial;
|
|
|
|
/* Call-bound packets are routed by connection channel. */
|
|
channel = sp->hdr.cid & RXRPC_CHANNELMASK;
|
|
chan = &conn->channels[channel];
|
|
|
|
/* Ignore really old calls */
|
|
if (sp->hdr.callNumber < chan->last_call)
|
|
goto discard;
|
|
|
|
if (sp->hdr.callNumber == chan->last_call) {
|
|
if (chan->call ||
|
|
sp->hdr.type == RXRPC_PACKET_TYPE_ABORT)
|
|
goto discard;
|
|
|
|
/* For the previous service call, if completed
|
|
* successfully, we discard all further packets.
|
|
*/
|
|
if (rxrpc_conn_is_service(conn) &&
|
|
chan->last_type == RXRPC_PACKET_TYPE_ACK)
|
|
goto discard;
|
|
|
|
/* But otherwise we need to retransmit the final packet
|
|
* from data cached in the connection record.
|
|
*/
|
|
if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA)
|
|
trace_rxrpc_rx_data(chan->call_debug_id,
|
|
sp->hdr.seq,
|
|
sp->hdr.serial,
|
|
sp->hdr.flags, 0);
|
|
rxrpc_post_packet_to_conn(conn, skb);
|
|
goto out;
|
|
}
|
|
|
|
call = rcu_dereference(chan->call);
|
|
|
|
if (sp->hdr.callNumber > chan->call_id) {
|
|
if (rxrpc_to_client(sp))
|
|
goto reject_packet;
|
|
if (call)
|
|
rxrpc_input_implicit_end_call(rx, conn, call);
|
|
call = NULL;
|
|
}
|
|
|
|
if (call) {
|
|
if (sp->hdr.serviceId != call->service_id)
|
|
call->service_id = sp->hdr.serviceId;
|
|
if ((int)sp->hdr.serial - (int)call->rx_serial > 0)
|
|
call->rx_serial = sp->hdr.serial;
|
|
if (!test_bit(RXRPC_CALL_RX_HEARD, &call->flags))
|
|
set_bit(RXRPC_CALL_RX_HEARD, &call->flags);
|
|
}
|
|
}
|
|
|
|
if (!call || atomic_read(&call->usage) == 0) {
|
|
if (rxrpc_to_client(sp) ||
|
|
sp->hdr.type != RXRPC_PACKET_TYPE_DATA)
|
|
goto bad_message;
|
|
if (sp->hdr.seq != 1)
|
|
goto discard;
|
|
call = rxrpc_new_incoming_call(local, rx, skb);
|
|
if (!call)
|
|
goto reject_packet;
|
|
}
|
|
|
|
/* Process a call packet; this either discards or passes on the ref
|
|
* elsewhere.
|
|
*/
|
|
rxrpc_input_call_packet(call, skb);
|
|
goto out;
|
|
|
|
discard:
|
|
rxrpc_free_skb(skb, rxrpc_skb_freed);
|
|
out:
|
|
trace_rxrpc_rx_done(0, 0);
|
|
return 0;
|
|
|
|
wrong_security:
|
|
trace_rxrpc_abort(0, "SEC", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
|
|
RXKADINCONSISTENCY, EBADMSG);
|
|
skb->priority = RXKADINCONSISTENCY;
|
|
goto post_abort;
|
|
|
|
unsupported_service:
|
|
trace_rxrpc_abort(0, "INV", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
|
|
RX_INVALID_OPERATION, EOPNOTSUPP);
|
|
skb->priority = RX_INVALID_OPERATION;
|
|
goto post_abort;
|
|
|
|
reupgrade:
|
|
trace_rxrpc_abort(0, "UPG", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
|
|
RX_PROTOCOL_ERROR, EBADMSG);
|
|
goto protocol_error;
|
|
|
|
bad_message:
|
|
trace_rxrpc_abort(0, "BAD", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
|
|
RX_PROTOCOL_ERROR, EBADMSG);
|
|
protocol_error:
|
|
skb->priority = RX_PROTOCOL_ERROR;
|
|
post_abort:
|
|
skb->mark = RXRPC_SKB_MARK_REJECT_ABORT;
|
|
reject_packet:
|
|
trace_rxrpc_rx_done(skb->mark, skb->priority);
|
|
rxrpc_reject_packet(local, skb);
|
|
_leave(" [badmsg]");
|
|
return 0;
|
|
}
|