![David Howells](/assets/img/avatar_default.png)
Sometimes an in-progress call will stop responding on the fileserver when the fileserver quietly cancels the call with an internally marked abort (RX_CALL_DEAD), without sending an ABORT to the client. This causes the client's call to eventually expire from lack of incoming packets directed its way, which currently leads to it being cancelled locally with ETIME. Note that it's not currently clear as to why this happens as it's really hard to reproduce. The rotation policy implement by kAFS, however, doesn't differentiate between ETIME meaning we didn't get any response from the server and ETIME meaning the call got cancelled mid-flow. The latter leads to an oops when fetching data as the rotation partially resets the afs_read descriptor, which can result in a cleared page pointer being dereferenced because that page has already been filled. Handle this by the following means: (1) Set a flag on a call when we receive a packet for it. (2) Store the highest packet serial number so far received for a call (bearing in mind this may wrap). (3) If, when the "not received anything recently" timeout expires on a call, we've received at least one packet for a call and the connection as a whole has received packets more recently than that call, then cancel the call locally with ECONNRESET rather than ETIME. This indicates that the call was definitely in progress on the server. (4) In kAFS, if the rotation algorithm sees ECONNRESET rather than ETIME, don't try the next server, but rather abort the call. This avoids the oops as we don't try to reuse the afs_read struct. Rather, as-yet ungotten pages will be reread at a later data. Also: (5) Add an rxrpc tracepoint to log detection of the call being reset. Without this, I occasionally see an oops like the following: general protection fault: 0000 [#1] SMP PTI ... RIP: 0010:_copy_to_iter+0x204/0x310 RSP: 0018:ffff8800cae0f828 EFLAGS: 00010206 RAX: 0000000000000560 RBX: 0000000000000560 RCX: 0000000000000560 RDX: ffff8800cae0f968 RSI: ffff8800d58b3312 RDI: 0005080000000000 RBP: ffff8800cae0f968 R08: 0000000000000560 R09: ffff8800ca00f400 R10: ffff8800c36f28d4 R11: 00000000000008c4 R12: ffff8800cae0f958 R13: 0000000000000560 R14: ffff8800d58b3312 R15: 0000000000000560 FS: 00007fdaef108080(0000) GS:ffff8800ca680000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb28a8fa000 CR3: 00000000d2a76002 CR4: 00000000001606e0 Call Trace: skb_copy_datagram_iter+0x14e/0x289 rxrpc_recvmsg_data.isra.0+0x6f3/0xf68 ? trace_buffer_unlock_commit_regs+0x4f/0x89 rxrpc_kernel_recv_data+0x149/0x421 afs_extract_data+0x1e0/0x798 ? afs_wait_for_call_to_complete+0xc9/0x52e afs_deliver_fs_fetch_data+0x33a/0x5ab afs_deliver_to_call+0x1ee/0x5e0 ? afs_wait_for_call_to_complete+0xc9/0x52e afs_wait_for_call_to_complete+0x12b/0x52e ? wake_up_q+0x54/0x54 afs_make_call+0x287/0x462 ? afs_fs_fetch_data+0x3e6/0x3ed ? rcu_read_lock_sched_held+0x5d/0x63 afs_fs_fetch_data+0x3e6/0x3ed afs_fetch_data+0xbb/0x14a afs_readpages+0x317/0x40d __do_page_cache_readahead+0x203/0x2ba ? ondemand_readahead+0x3a7/0x3c1 ondemand_readahead+0x3a7/0x3c1 generic_file_buffered_read+0x18b/0x62f __vfs_read+0xdb/0xfe vfs_read+0xb2/0x137 ksys_read+0x50/0x8c do_syscall_64+0x7d/0x1a0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Note the weird value in RDI which is a result of trying to kmap() a NULL page pointer. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1352 lines
35 KiB
C
1352 lines
35 KiB
C
/* RxRPC packet reception
|
|
*
|
|
* Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/net.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/errqueue.h>
|
|
#include <linux/udp.h>
|
|
#include <linux/in.h>
|
|
#include <linux/in6.h>
|
|
#include <linux/icmp.h>
|
|
#include <linux/gfp.h>
|
|
#include <net/sock.h>
|
|
#include <net/af_rxrpc.h>
|
|
#include <net/ip.h>
|
|
#include <net/udp.h>
|
|
#include <net/net_namespace.h>
|
|
#include "ar-internal.h"
|
|
|
|
static void rxrpc_proto_abort(const char *why,
|
|
struct rxrpc_call *call, rxrpc_seq_t seq)
|
|
{
|
|
if (rxrpc_abort_call(why, call, seq, RX_PROTOCOL_ERROR, -EBADMSG)) {
|
|
set_bit(RXRPC_CALL_EV_ABORT, &call->events);
|
|
rxrpc_queue_call(call);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Do TCP-style congestion management [RFC 5681].
|
|
*/
|
|
static void rxrpc_congestion_management(struct rxrpc_call *call,
|
|
struct sk_buff *skb,
|
|
struct rxrpc_ack_summary *summary,
|
|
rxrpc_serial_t acked_serial)
|
|
{
|
|
enum rxrpc_congest_change change = rxrpc_cong_no_change;
|
|
unsigned int cumulative_acks = call->cong_cumul_acks;
|
|
unsigned int cwnd = call->cong_cwnd;
|
|
bool resend = false;
|
|
|
|
summary->flight_size =
|
|
(call->tx_top - call->tx_hard_ack) - summary->nr_acks;
|
|
|
|
if (test_and_clear_bit(RXRPC_CALL_RETRANS_TIMEOUT, &call->flags)) {
|
|
summary->retrans_timeo = true;
|
|
call->cong_ssthresh = max_t(unsigned int,
|
|
summary->flight_size / 2, 2);
|
|
cwnd = 1;
|
|
if (cwnd >= call->cong_ssthresh &&
|
|
call->cong_mode == RXRPC_CALL_SLOW_START) {
|
|
call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
|
|
call->cong_tstamp = skb->tstamp;
|
|
cumulative_acks = 0;
|
|
}
|
|
}
|
|
|
|
cumulative_acks += summary->nr_new_acks;
|
|
cumulative_acks += summary->nr_rot_new_acks;
|
|
if (cumulative_acks > 255)
|
|
cumulative_acks = 255;
|
|
|
|
summary->mode = call->cong_mode;
|
|
summary->cwnd = call->cong_cwnd;
|
|
summary->ssthresh = call->cong_ssthresh;
|
|
summary->cumulative_acks = cumulative_acks;
|
|
summary->dup_acks = call->cong_dup_acks;
|
|
|
|
switch (call->cong_mode) {
|
|
case RXRPC_CALL_SLOW_START:
|
|
if (summary->nr_nacks > 0)
|
|
goto packet_loss_detected;
|
|
if (summary->cumulative_acks > 0)
|
|
cwnd += 1;
|
|
if (cwnd >= call->cong_ssthresh) {
|
|
call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
|
|
call->cong_tstamp = skb->tstamp;
|
|
}
|
|
goto out;
|
|
|
|
case RXRPC_CALL_CONGEST_AVOIDANCE:
|
|
if (summary->nr_nacks > 0)
|
|
goto packet_loss_detected;
|
|
|
|
/* We analyse the number of packets that get ACK'd per RTT
|
|
* period and increase the window if we managed to fill it.
|
|
*/
|
|
if (call->peer->rtt_usage == 0)
|
|
goto out;
|
|
if (ktime_before(skb->tstamp,
|
|
ktime_add_ns(call->cong_tstamp,
|
|
call->peer->rtt)))
|
|
goto out_no_clear_ca;
|
|
change = rxrpc_cong_rtt_window_end;
|
|
call->cong_tstamp = skb->tstamp;
|
|
if (cumulative_acks >= cwnd)
|
|
cwnd++;
|
|
goto out;
|
|
|
|
case RXRPC_CALL_PACKET_LOSS:
|
|
if (summary->nr_nacks == 0)
|
|
goto resume_normality;
|
|
|
|
if (summary->new_low_nack) {
|
|
change = rxrpc_cong_new_low_nack;
|
|
call->cong_dup_acks = 1;
|
|
if (call->cong_extra > 1)
|
|
call->cong_extra = 1;
|
|
goto send_extra_data;
|
|
}
|
|
|
|
call->cong_dup_acks++;
|
|
if (call->cong_dup_acks < 3)
|
|
goto send_extra_data;
|
|
|
|
change = rxrpc_cong_begin_retransmission;
|
|
call->cong_mode = RXRPC_CALL_FAST_RETRANSMIT;
|
|
call->cong_ssthresh = max_t(unsigned int,
|
|
summary->flight_size / 2, 2);
|
|
cwnd = call->cong_ssthresh + 3;
|
|
call->cong_extra = 0;
|
|
call->cong_dup_acks = 0;
|
|
resend = true;
|
|
goto out;
|
|
|
|
case RXRPC_CALL_FAST_RETRANSMIT:
|
|
if (!summary->new_low_nack) {
|
|
if (summary->nr_new_acks == 0)
|
|
cwnd += 1;
|
|
call->cong_dup_acks++;
|
|
if (call->cong_dup_acks == 2) {
|
|
change = rxrpc_cong_retransmit_again;
|
|
call->cong_dup_acks = 0;
|
|
resend = true;
|
|
}
|
|
} else {
|
|
change = rxrpc_cong_progress;
|
|
cwnd = call->cong_ssthresh;
|
|
if (summary->nr_nacks == 0)
|
|
goto resume_normality;
|
|
}
|
|
goto out;
|
|
|
|
default:
|
|
BUG();
|
|
goto out;
|
|
}
|
|
|
|
resume_normality:
|
|
change = rxrpc_cong_cleared_nacks;
|
|
call->cong_dup_acks = 0;
|
|
call->cong_extra = 0;
|
|
call->cong_tstamp = skb->tstamp;
|
|
if (cwnd < call->cong_ssthresh)
|
|
call->cong_mode = RXRPC_CALL_SLOW_START;
|
|
else
|
|
call->cong_mode = RXRPC_CALL_CONGEST_AVOIDANCE;
|
|
out:
|
|
cumulative_acks = 0;
|
|
out_no_clear_ca:
|
|
if (cwnd >= RXRPC_RXTX_BUFF_SIZE - 1)
|
|
cwnd = RXRPC_RXTX_BUFF_SIZE - 1;
|
|
call->cong_cwnd = cwnd;
|
|
call->cong_cumul_acks = cumulative_acks;
|
|
trace_rxrpc_congest(call, summary, acked_serial, change);
|
|
if (resend && !test_and_set_bit(RXRPC_CALL_EV_RESEND, &call->events))
|
|
rxrpc_queue_call(call);
|
|
return;
|
|
|
|
packet_loss_detected:
|
|
change = rxrpc_cong_saw_nack;
|
|
call->cong_mode = RXRPC_CALL_PACKET_LOSS;
|
|
call->cong_dup_acks = 0;
|
|
goto send_extra_data;
|
|
|
|
send_extra_data:
|
|
/* Send some previously unsent DATA if we have some to advance the ACK
|
|
* state.
|
|
*/
|
|
if (call->rxtx_annotations[call->tx_top & RXRPC_RXTX_BUFF_MASK] &
|
|
RXRPC_TX_ANNO_LAST ||
|
|
summary->nr_acks != call->tx_top - call->tx_hard_ack) {
|
|
call->cong_extra++;
|
|
wake_up(&call->waitq);
|
|
}
|
|
goto out_no_clear_ca;
|
|
}
|
|
|
|
/*
|
|
* Ping the other end to fill our RTT cache and to retrieve the rwind
|
|
* and MTU parameters.
|
|
*/
|
|
static void rxrpc_send_ping(struct rxrpc_call *call, struct sk_buff *skb,
|
|
int skew)
|
|
{
|
|
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
|
|
ktime_t now = skb->tstamp;
|
|
|
|
if (call->peer->rtt_usage < 3 ||
|
|
ktime_before(ktime_add_ms(call->peer->rtt_last_req, 1000), now))
|
|
rxrpc_propose_ACK(call, RXRPC_ACK_PING, skew, sp->hdr.serial,
|
|
true, true,
|
|
rxrpc_propose_ack_ping_for_params);
|
|
}
|
|
|
|
/*
|
|
* Apply a hard ACK by advancing the Tx window.
|
|
*/
|
|
static void rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to,
|
|
struct rxrpc_ack_summary *summary)
|
|
{
|
|
struct sk_buff *skb, *list = NULL;
|
|
int ix;
|
|
u8 annotation;
|
|
|
|
if (call->acks_lowest_nak == call->tx_hard_ack) {
|
|
call->acks_lowest_nak = to;
|
|
} else if (before_eq(call->acks_lowest_nak, to)) {
|
|
summary->new_low_nack = true;
|
|
call->acks_lowest_nak = to;
|
|
}
|
|
|
|
spin_lock(&call->lock);
|
|
|
|
while (before(call->tx_hard_ack, to)) {
|
|
call->tx_hard_ack++;
|
|
ix = call->tx_hard_ack & RXRPC_RXTX_BUFF_MASK;
|
|
skb = call->rxtx_buffer[ix];
|
|
annotation = call->rxtx_annotations[ix];
|
|
rxrpc_see_skb(skb, rxrpc_skb_tx_rotated);
|
|
call->rxtx_buffer[ix] = NULL;
|
|
call->rxtx_annotations[ix] = 0;
|
|
skb->next = list;
|
|
list = skb;
|
|
|
|
if (annotation & RXRPC_TX_ANNO_LAST)
|
|
set_bit(RXRPC_CALL_TX_LAST, &call->flags);
|
|
if ((annotation & RXRPC_TX_ANNO_MASK) != RXRPC_TX_ANNO_ACK)
|
|
summary->nr_rot_new_acks++;
|
|
}
|
|
|
|
spin_unlock(&call->lock);
|
|
|
|
trace_rxrpc_transmit(call, (test_bit(RXRPC_CALL_TX_LAST, &call->flags) ?
|
|
rxrpc_transmit_rotate_last :
|
|
rxrpc_transmit_rotate));
|
|
wake_up(&call->waitq);
|
|
|
|
while (list) {
|
|
skb = list;
|
|
list = skb->next;
|
|
skb->next = NULL;
|
|
rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* End the transmission phase of a call.
|
|
*
|
|
* This occurs when we get an ACKALL packet, the first DATA packet of a reply,
|
|
* or a final ACK packet.
|
|
*/
|
|
static bool rxrpc_end_tx_phase(struct rxrpc_call *call, bool reply_begun,
|
|
const char *abort_why)
|
|
{
|
|
|
|
ASSERT(test_bit(RXRPC_CALL_TX_LAST, &call->flags));
|
|
|
|
write_lock(&call->state_lock);
|
|
|
|
switch (call->state) {
|
|
case RXRPC_CALL_CLIENT_SEND_REQUEST:
|
|
case RXRPC_CALL_CLIENT_AWAIT_REPLY:
|
|
if (reply_begun)
|
|
call->state = RXRPC_CALL_CLIENT_RECV_REPLY;
|
|
else
|
|
call->state = RXRPC_CALL_CLIENT_AWAIT_REPLY;
|
|
break;
|
|
|
|
case RXRPC_CALL_SERVER_AWAIT_ACK:
|
|
__rxrpc_call_completed(call);
|
|
rxrpc_notify_socket(call);
|
|
break;
|
|
|
|
default:
|
|
goto bad_state;
|
|
}
|
|
|
|
write_unlock(&call->state_lock);
|
|
if (call->state == RXRPC_CALL_CLIENT_AWAIT_REPLY) {
|
|
trace_rxrpc_transmit(call, rxrpc_transmit_await_reply);
|
|
} else {
|
|
trace_rxrpc_transmit(call, rxrpc_transmit_end);
|
|
}
|
|
_leave(" = ok");
|
|
return true;
|
|
|
|
bad_state:
|
|
write_unlock(&call->state_lock);
|
|
kdebug("end_tx %s", rxrpc_call_states[call->state]);
|
|
rxrpc_proto_abort(abort_why, call, call->tx_top);
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Begin the reply reception phase of a call.
|
|
*/
|
|
static bool rxrpc_receiving_reply(struct rxrpc_call *call)
|
|
{
|
|
struct rxrpc_ack_summary summary = { 0 };
|
|
unsigned long now, timo;
|
|
rxrpc_seq_t top = READ_ONCE(call->tx_top);
|
|
|
|
if (call->ackr_reason) {
|
|
spin_lock_bh(&call->lock);
|
|
call->ackr_reason = 0;
|
|
spin_unlock_bh(&call->lock);
|
|
now = jiffies;
|
|
timo = now + MAX_JIFFY_OFFSET;
|
|
WRITE_ONCE(call->resend_at, timo);
|
|
WRITE_ONCE(call->ack_at, timo);
|
|
trace_rxrpc_timer(call, rxrpc_timer_init_for_reply, now);
|
|
}
|
|
|
|
if (!test_bit(RXRPC_CALL_TX_LAST, &call->flags))
|
|
rxrpc_rotate_tx_window(call, top, &summary);
|
|
if (!test_bit(RXRPC_CALL_TX_LAST, &call->flags)) {
|
|
rxrpc_proto_abort("TXL", call, top);
|
|
return false;
|
|
}
|
|
if (!rxrpc_end_tx_phase(call, true, "ETD"))
|
|
return false;
|
|
call->tx_phase = false;
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Scan a jumbo packet to validate its structure and to work out how many
|
|
* subpackets it contains.
|
|
*
|
|
* A jumbo packet is a collection of consecutive packets glued together with
|
|
* little headers between that indicate how to change the initial header for
|
|
* each subpacket.
|
|
*
|
|
* RXRPC_JUMBO_PACKET must be set on all but the last subpacket - and all but
|
|
* the last are RXRPC_JUMBO_DATALEN in size. The last subpacket may be of any
|
|
* size.
|
|
*/
|
|
static bool rxrpc_validate_jumbo(struct sk_buff *skb)
|
|
{
|
|
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
|
|
unsigned int offset = sizeof(struct rxrpc_wire_header);
|
|
unsigned int len = skb->len;
|
|
int nr_jumbo = 1;
|
|
u8 flags = sp->hdr.flags;
|
|
|
|
do {
|
|
nr_jumbo++;
|
|
if (len - offset < RXRPC_JUMBO_SUBPKTLEN)
|
|
goto protocol_error;
|
|
if (flags & RXRPC_LAST_PACKET)
|
|
goto protocol_error;
|
|
offset += RXRPC_JUMBO_DATALEN;
|
|
if (skb_copy_bits(skb, offset, &flags, 1) < 0)
|
|
goto protocol_error;
|
|
offset += sizeof(struct rxrpc_jumbo_header);
|
|
} while (flags & RXRPC_JUMBO_PACKET);
|
|
|
|
sp->nr_jumbo = nr_jumbo;
|
|
return true;
|
|
|
|
protocol_error:
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Handle reception of a duplicate packet.
|
|
*
|
|
* We have to take care to avoid an attack here whereby we're given a series of
|
|
* jumbograms, each with a sequence number one before the preceding one and
|
|
* filled up to maximum UDP size. If they never send us the first packet in
|
|
* the sequence, they can cause us to have to hold on to around 2MiB of kernel
|
|
* space until the call times out.
|
|
*
|
|
* We limit the space usage by only accepting three duplicate jumbo packets per
|
|
* call. After that, we tell the other side we're no longer accepting jumbos
|
|
* (that information is encoded in the ACK packet).
|
|
*/
|
|
static void rxrpc_input_dup_data(struct rxrpc_call *call, rxrpc_seq_t seq,
|
|
u8 annotation, bool *_jumbo_bad)
|
|
{
|
|
/* Discard normal packets that are duplicates. */
|
|
if (annotation == 0)
|
|
return;
|
|
|
|
/* Skip jumbo subpackets that are duplicates. When we've had three or
|
|
* more partially duplicate jumbo packets, we refuse to take any more
|
|
* jumbos for this call.
|
|
*/
|
|
if (!*_jumbo_bad) {
|
|
call->nr_jumbo_bad++;
|
|
*_jumbo_bad = true;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Process a DATA packet, adding the packet to the Rx ring.
|
|
*/
|
|
static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb,
|
|
u16 skew)
|
|
{
|
|
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
|
|
enum rxrpc_call_state state;
|
|
unsigned int offset = sizeof(struct rxrpc_wire_header);
|
|
unsigned int ix;
|
|
rxrpc_serial_t serial = sp->hdr.serial, ack_serial = 0;
|
|
rxrpc_seq_t seq = sp->hdr.seq, hard_ack;
|
|
bool immediate_ack = false, jumbo_bad = false, queued;
|
|
u16 len;
|
|
u8 ack = 0, flags, annotation = 0;
|
|
|
|
_enter("{%u,%u},{%u,%u}",
|
|
call->rx_hard_ack, call->rx_top, skb->len, seq);
|
|
|
|
_proto("Rx DATA %%%u { #%u f=%02x }",
|
|
sp->hdr.serial, seq, sp->hdr.flags);
|
|
|
|
state = READ_ONCE(call->state);
|
|
if (state >= RXRPC_CALL_COMPLETE)
|
|
return;
|
|
|
|
if (call->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,
|
|
rxrpc_timer_set_for_idle);
|
|
}
|
|
}
|
|
|
|
/* 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))
|
|
return;
|
|
|
|
call->ackr_prev_seq = seq;
|
|
|
|
hard_ack = READ_ONCE(call->rx_hard_ack);
|
|
if (after(seq, hard_ack + call->rx_winsize)) {
|
|
ack = RXRPC_ACK_EXCEEDS_WINDOW;
|
|
ack_serial = serial;
|
|
goto ack;
|
|
}
|
|
|
|
flags = sp->hdr.flags;
|
|
if (flags & RXRPC_JUMBO_PACKET) {
|
|
if (call->nr_jumbo_bad > 3) {
|
|
ack = RXRPC_ACK_NOSPACE;
|
|
ack_serial = serial;
|
|
goto ack;
|
|
}
|
|
annotation = 1;
|
|
}
|
|
|
|
next_subpacket:
|
|
queued = false;
|
|
ix = seq & RXRPC_RXTX_BUFF_MASK;
|
|
len = skb->len;
|
|
if (flags & RXRPC_JUMBO_PACKET)
|
|
len = RXRPC_JUMBO_DATALEN;
|
|
|
|
if (flags & RXRPC_LAST_PACKET) {
|
|
if (test_bit(RXRPC_CALL_RX_LAST, &call->flags) &&
|
|
seq != call->rx_top)
|
|
return rxrpc_proto_abort("LSN", call, seq);
|
|
} else {
|
|
if (test_bit(RXRPC_CALL_RX_LAST, &call->flags) &&
|
|
after_eq(seq, call->rx_top))
|
|
return rxrpc_proto_abort("LSA", call, seq);
|
|
}
|
|
|
|
trace_rxrpc_rx_data(call, seq, serial, flags, annotation);
|
|
if (before_eq(seq, hard_ack)) {
|
|
ack = RXRPC_ACK_DUPLICATE;
|
|
ack_serial = serial;
|
|
goto skip;
|
|
}
|
|
|
|
if (flags & RXRPC_REQUEST_ACK && !ack) {
|
|
ack = RXRPC_ACK_REQUESTED;
|
|
ack_serial = serial;
|
|
}
|
|
|
|
if (call->rxtx_buffer[ix]) {
|
|
rxrpc_input_dup_data(call, seq, annotation, &jumbo_bad);
|
|
if (ack != RXRPC_ACK_DUPLICATE) {
|
|
ack = RXRPC_ACK_DUPLICATE;
|
|
ack_serial = serial;
|
|
}
|
|
immediate_ack = true;
|
|
goto skip;
|
|
}
|
|
|
|
/* 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().
|
|
*/
|
|
rxrpc_get_skb(skb, rxrpc_skb_rx_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 (flags & RXRPC_LAST_PACKET) {
|
|
set_bit(RXRPC_CALL_RX_LAST, &call->flags);
|
|
trace_rxrpc_receive(call, rxrpc_receive_queue_last, serial, seq);
|
|
} else {
|
|
trace_rxrpc_receive(call, rxrpc_receive_queue, serial, seq);
|
|
}
|
|
queued = true;
|
|
|
|
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;
|
|
}
|
|
|
|
skip:
|
|
offset += len;
|
|
if (flags & RXRPC_JUMBO_PACKET) {
|
|
if (skb_copy_bits(skb, offset, &flags, 1) < 0)
|
|
return rxrpc_proto_abort("XJF", call, seq);
|
|
offset += sizeof(struct rxrpc_jumbo_header);
|
|
seq++;
|
|
serial++;
|
|
annotation++;
|
|
if (flags & RXRPC_JUMBO_PACKET)
|
|
annotation |= RXRPC_RX_ANNO_JLAST;
|
|
if (after(seq, hard_ack + call->rx_winsize)) {
|
|
ack = RXRPC_ACK_EXCEEDS_WINDOW;
|
|
ack_serial = serial;
|
|
if (!jumbo_bad) {
|
|
call->nr_jumbo_bad++;
|
|
jumbo_bad = true;
|
|
}
|
|
goto ack;
|
|
}
|
|
|
|
_proto("Rx DATA Jumbo %%%u", serial);
|
|
goto next_subpacket;
|
|
}
|
|
|
|
if (queued && flags & RXRPC_LAST_PACKET && !ack) {
|
|
ack = RXRPC_ACK_DELAY;
|
|
ack_serial = serial;
|
|
}
|
|
|
|
ack:
|
|
if (ack)
|
|
rxrpc_propose_ACK(call, ack, skew, ack_serial,
|
|
immediate_ack, true,
|
|
rxrpc_propose_ack_input_data);
|
|
|
|
if (sp->hdr.seq == READ_ONCE(call->rx_hard_ack) + 1)
|
|
rxrpc_notify_socket(call);
|
|
_leave(" [queued]");
|
|
}
|
|
|
|
/*
|
|
* Process a requested ACK.
|
|
*/
|
|
static void rxrpc_input_requested_ack(struct rxrpc_call *call,
|
|
ktime_t resp_time,
|
|
rxrpc_serial_t orig_serial,
|
|
rxrpc_serial_t ack_serial)
|
|
{
|
|
struct rxrpc_skb_priv *sp;
|
|
struct sk_buff *skb;
|
|
ktime_t sent_at;
|
|
int ix;
|
|
|
|
for (ix = 0; ix < RXRPC_RXTX_BUFF_SIZE; ix++) {
|
|
skb = call->rxtx_buffer[ix];
|
|
if (!skb)
|
|
continue;
|
|
|
|
sp = rxrpc_skb(skb);
|
|
if (sp->hdr.serial != orig_serial)
|
|
continue;
|
|
smp_rmb();
|
|
sent_at = skb->tstamp;
|
|
goto found;
|
|
}
|
|
return;
|
|
|
|
found:
|
|
rxrpc_peer_add_rtt(call, rxrpc_rtt_rx_requested_ack,
|
|
orig_serial, ack_serial, sent_at, resp_time);
|
|
}
|
|
|
|
/*
|
|
* 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 orig_serial,
|
|
rxrpc_serial_t ack_serial)
|
|
{
|
|
rxrpc_serial_t ping_serial;
|
|
ktime_t ping_time;
|
|
|
|
ping_time = call->ping_time;
|
|
smp_rmb();
|
|
ping_serial = call->ping_serial;
|
|
|
|
if (orig_serial == call->acks_lost_ping)
|
|
rxrpc_input_check_for_lost_ack(call);
|
|
|
|
if (!test_bit(RXRPC_CALL_PINGING, &call->flags) ||
|
|
before(orig_serial, ping_serial))
|
|
return;
|
|
clear_bit(RXRPC_CALL_PINGING, &call->flags);
|
|
if (after(orig_serial, ping_serial))
|
|
return;
|
|
|
|
rxrpc_peer_add_rtt(call, rxrpc_rtt_rx_ping_response,
|
|
orig_serial, ack_serial, ping_time, resp_time);
|
|
}
|
|
|
|
/*
|
|
* 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 (call->tx_winsize != rwind) {
|
|
if (rwind > RXRPC_RXTX_BUFF_SIZE - 1)
|
|
rwind = RXRPC_RXTX_BUFF_SIZE - 1;
|
|
if (rwind > call->tx_winsize)
|
|
wake = true;
|
|
trace_rxrpc_rx_rwind_change(call, sp->hdr.serial,
|
|
ntohl(ackinfo->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);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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,
|
|
u16 skew)
|
|
{
|
|
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 acked_serial;
|
|
rxrpc_seq_t first_soft_ack, hard_ack;
|
|
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);
|
|
|
|
acked_serial = ntohl(buf.ack.serial);
|
|
first_soft_ack = ntohl(buf.ack.firstPacket);
|
|
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, sp->hdr.serial, acked_serial,
|
|
first_soft_ack, ntohl(buf.ack.previousPacket),
|
|
summary.ack_reason, nr_acks);
|
|
|
|
if (buf.ack.reason == RXRPC_ACK_PING_RESPONSE)
|
|
rxrpc_input_ping_response(call, skb->tstamp, acked_serial,
|
|
sp->hdr.serial);
|
|
if (buf.ack.reason == RXRPC_ACK_REQUESTED)
|
|
rxrpc_input_requested_ack(call, skb->tstamp, acked_serial,
|
|
sp->hdr.serial);
|
|
|
|
if (buf.ack.reason == RXRPC_ACK_PING) {
|
|
_proto("Rx ACK %%%u PING Request", sp->hdr.serial);
|
|
rxrpc_propose_ACK(call, RXRPC_ACK_PING_RESPONSE,
|
|
skew, sp->hdr.serial, true, true,
|
|
rxrpc_propose_ack_respond_to_ping);
|
|
} else if (sp->hdr.flags & RXRPC_REQUEST_ACK) {
|
|
rxrpc_propose_ACK(call, RXRPC_ACK_REQUESTED,
|
|
skew, sp->hdr.serial, true, true,
|
|
rxrpc_propose_ack_respond_to_ack);
|
|
}
|
|
|
|
ioffset = offset + nr_acks + 3;
|
|
if (skb->len >= ioffset + sizeof(buf.info)) {
|
|
if (skb_copy_bits(skb, ioffset, &buf.info, sizeof(buf.info)) < 0)
|
|
return rxrpc_proto_abort("XAI", call, 0);
|
|
rxrpc_input_ackinfo(call, skb, &buf.info);
|
|
}
|
|
|
|
if (first_soft_ack == 0)
|
|
return rxrpc_proto_abort("AK0", call, 0);
|
|
|
|
/* 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:
|
|
return;
|
|
}
|
|
|
|
/* Discard any out-of-order or duplicate ACKs. */
|
|
if (before_eq(sp->hdr.serial, call->acks_latest)) {
|
|
_debug("discard ACK %d <= %d",
|
|
sp->hdr.serial, call->acks_latest);
|
|
return;
|
|
}
|
|
call->acks_latest_ts = skb->tstamp;
|
|
call->acks_latest = sp->hdr.serial;
|
|
|
|
if (before(hard_ack, call->tx_hard_ack) ||
|
|
after(hard_ack, call->tx_top))
|
|
return rxrpc_proto_abort("AKW", call, 0);
|
|
if (nr_acks > call->tx_top - hard_ack)
|
|
return rxrpc_proto_abort("AKN", call, 0);
|
|
|
|
if (after(hard_ack, call->tx_hard_ack))
|
|
rxrpc_rotate_tx_window(call, hard_ack, &summary);
|
|
|
|
if (nr_acks > 0) {
|
|
if (skb_copy_bits(skb, offset, buf.acks, nr_acks) < 0)
|
|
return rxrpc_proto_abort("XSA", call, 0);
|
|
rxrpc_input_soft_acks(call, buf.acks, first_soft_ack, nr_acks,
|
|
&summary);
|
|
}
|
|
|
|
if (test_bit(RXRPC_CALL_TX_LAST, &call->flags)) {
|
|
rxrpc_end_tx_phase(call, false, "ETA");
|
|
return;
|
|
}
|
|
|
|
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, skew, sp->hdr.serial,
|
|
false, true,
|
|
rxrpc_propose_ack_ping_for_lost_reply);
|
|
|
|
return rxrpc_congestion_management(call, skb, &summary, acked_serial);
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
|
|
rxrpc_rotate_tx_window(call, call->tx_top, &summary);
|
|
if (test_bit(RXRPC_CALL_TX_LAST, &call->flags))
|
|
rxrpc_end_tx_phase(call, false, "ETL");
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
|
|
if (rxrpc_set_call_completion(call, RXRPC_CALL_REMOTELY_ABORTED,
|
|
abort_code, -ECONNABORTED))
|
|
rxrpc_notify_socket(call);
|
|
}
|
|
|
|
/*
|
|
* Process an incoming call packet.
|
|
*/
|
|
static void rxrpc_input_call_packet(struct rxrpc_call *call,
|
|
struct sk_buff *skb, u16 skew)
|
|
{
|
|
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, skew);
|
|
break;
|
|
|
|
case RXRPC_PACKET_TYPE_ACK:
|
|
rxrpc_input_ack(call, skb, skew);
|
|
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;
|
|
}
|
|
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* Handle a new call on a channel implicitly completing the preceding call on
|
|
* that channel.
|
|
*
|
|
* TODO: If callNumber > call_id + 1, renegotiate security.
|
|
*/
|
|
static void rxrpc_input_implicit_end_call(struct rxrpc_connection *conn,
|
|
struct rxrpc_call *call)
|
|
{
|
|
switch (READ_ONCE(call->state)) {
|
|
case RXRPC_CALL_SERVER_AWAIT_ACK:
|
|
rxrpc_call_completed(call);
|
|
break;
|
|
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);
|
|
}
|
|
break;
|
|
}
|
|
|
|
trace_rxrpc_improper_term(call);
|
|
__rxrpc_disconnect_call(conn, call);
|
|
rxrpc_notify_socket(call);
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
|
|
skb_queue_tail(&local->event_queue, skb);
|
|
rxrpc_queue_local(local);
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
|
|
skb_queue_tail(&local->reject_queue, skb);
|
|
rxrpc_queue_local(local);
|
|
}
|
|
|
|
/*
|
|
* 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
|
|
*
|
|
* The socket is locked by the caller and this prevents the socket from being
|
|
* shut down and the local endpoint from going away, thus sk_user_data will not
|
|
* be cleared until this function returns.
|
|
*/
|
|
void rxrpc_data_ready(struct sock *udp_sk)
|
|
{
|
|
struct rxrpc_connection *conn;
|
|
struct rxrpc_channel *chan;
|
|
struct rxrpc_call *call;
|
|
struct rxrpc_skb_priv *sp;
|
|
struct rxrpc_local *local = udp_sk->sk_user_data;
|
|
struct sk_buff *skb;
|
|
unsigned int channel;
|
|
int ret, skew;
|
|
|
|
_enter("%p", udp_sk);
|
|
|
|
ASSERT(!irqs_disabled());
|
|
|
|
skb = skb_recv_udp(udp_sk, 0, 1, &ret);
|
|
if (!skb) {
|
|
if (ret == -EAGAIN)
|
|
return;
|
|
_debug("UDP socket error %d", ret);
|
|
return;
|
|
}
|
|
|
|
rxrpc_new_skb(skb, rxrpc_skb_rx_received);
|
|
|
|
_net("recv skb %p", skb);
|
|
|
|
/* we'll probably need to checksum it (didn't call sock_recvmsg) */
|
|
if (skb_checksum_complete(skb)) {
|
|
rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
|
|
__UDP_INC_STATS(&init_net, UDP_MIB_INERRORS, 0);
|
|
_leave(" [CSUM failed]");
|
|
return;
|
|
}
|
|
|
|
__UDP_INC_STATS(&init_net, UDP_MIB_INDATAGRAMS, 0);
|
|
|
|
/* 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_lose_skb(skb, rxrpc_skb_rx_lost);
|
|
return;
|
|
}
|
|
}
|
|
|
|
trace_rxrpc_rx_packet(sp);
|
|
|
|
_net("Rx RxRPC %s ep=%x call=%x:%x",
|
|
sp->hdr.flags & RXRPC_CLIENT_INITIATED ? "ToServer" : "ToClient",
|
|
sp->hdr.epoch, sp->hdr.cid, sp->hdr.callNumber);
|
|
|
|
if (sp->hdr.type >= RXRPC_N_PACKET_TYPES ||
|
|
!((RXRPC_SUPPORTED_PACKET_TYPES >> sp->hdr.type) & 1)) {
|
|
_proto("Rx Bad Packet Type %u", sp->hdr.type);
|
|
goto bad_message;
|
|
}
|
|
|
|
switch (sp->hdr.type) {
|
|
case RXRPC_PACKET_TYPE_VERSION:
|
|
if (!(sp->hdr.flags & RXRPC_CLIENT_INITIATED))
|
|
goto discard;
|
|
rxrpc_post_packet_to_local(local, skb);
|
|
goto out;
|
|
|
|
case RXRPC_PACKET_TYPE_BUSY:
|
|
if (sp->hdr.flags & RXRPC_CLIENT_INITIATED)
|
|
goto discard;
|
|
/* Fall through */
|
|
|
|
case RXRPC_PACKET_TYPE_DATA:
|
|
if (sp->hdr.callNumber == 0)
|
|
goto bad_message;
|
|
if (sp->hdr.flags & RXRPC_JUMBO_PACKET &&
|
|
!rxrpc_validate_jumbo(skb))
|
|
goto bad_message;
|
|
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;
|
|
}
|
|
|
|
rcu_read_lock();
|
|
|
|
conn = rxrpc_find_connection_rcu(local, skb);
|
|
if (conn) {
|
|
if (sp->hdr.securityIndex != conn->security_ix)
|
|
goto wrong_security;
|
|
|
|
if (sp->hdr.serviceId != conn->service_id) {
|
|
if (!test_bit(RXRPC_CONN_PROBING_FOR_UPGRADE, &conn->flags) ||
|
|
conn->service_id != conn->params.service_id)
|
|
goto reupgrade;
|
|
conn->service_id = sp->hdr.serviceId;
|
|
}
|
|
|
|
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_unlock;
|
|
}
|
|
|
|
/* Note the serial number skew here */
|
|
skew = (int)sp->hdr.serial - (int)conn->hi_serial;
|
|
if (skew >= 0) {
|
|
if (skew > 0)
|
|
conn->hi_serial = sp->hdr.serial;
|
|
} else {
|
|
skew = -skew;
|
|
skew = min(skew, 65535);
|
|
}
|
|
|
|
/* 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_unlock;
|
|
|
|
if (sp->hdr.callNumber == chan->last_call) {
|
|
if (chan->call ||
|
|
sp->hdr.type == RXRPC_PACKET_TYPE_ABORT)
|
|
goto discard_unlock;
|
|
|
|
/* 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_unlock;
|
|
|
|
/* But otherwise we need to retransmit the final packet
|
|
* from data cached in the connection record.
|
|
*/
|
|
rxrpc_post_packet_to_conn(conn, skb);
|
|
goto out_unlock;
|
|
}
|
|
|
|
call = rcu_dereference(chan->call);
|
|
|
|
if (sp->hdr.callNumber > chan->call_id) {
|
|
if (!(sp->hdr.flags & RXRPC_CLIENT_INITIATED)) {
|
|
rcu_read_unlock();
|
|
goto reject_packet;
|
|
}
|
|
if (call)
|
|
rxrpc_input_implicit_end_call(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);
|
|
}
|
|
} else {
|
|
skew = 0;
|
|
call = NULL;
|
|
}
|
|
|
|
if (!call || atomic_read(&call->usage) == 0) {
|
|
if (!(sp->hdr.type & RXRPC_CLIENT_INITIATED) ||
|
|
sp->hdr.callNumber == 0 ||
|
|
sp->hdr.type != RXRPC_PACKET_TYPE_DATA)
|
|
goto bad_message_unlock;
|
|
if (sp->hdr.seq != 1)
|
|
goto discard_unlock;
|
|
call = rxrpc_new_incoming_call(local, conn, skb);
|
|
if (!call) {
|
|
rcu_read_unlock();
|
|
goto reject_packet;
|
|
}
|
|
rxrpc_send_ping(call, skb, skew);
|
|
mutex_unlock(&call->user_mutex);
|
|
}
|
|
|
|
rxrpc_input_call_packet(call, skb, skew);
|
|
goto discard_unlock;
|
|
|
|
discard_unlock:
|
|
rcu_read_unlock();
|
|
discard:
|
|
rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
|
|
out:
|
|
trace_rxrpc_rx_done(0, 0);
|
|
return;
|
|
|
|
out_unlock:
|
|
rcu_read_unlock();
|
|
goto out;
|
|
|
|
wrong_security:
|
|
rcu_read_unlock();
|
|
trace_rxrpc_abort(0, "SEC", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
|
|
RXKADINCONSISTENCY, EBADMSG);
|
|
skb->priority = RXKADINCONSISTENCY;
|
|
goto post_abort;
|
|
|
|
reupgrade:
|
|
rcu_read_unlock();
|
|
trace_rxrpc_abort(0, "UPG", sp->hdr.cid, sp->hdr.callNumber, sp->hdr.seq,
|
|
RX_PROTOCOL_ERROR, EBADMSG);
|
|
goto protocol_error;
|
|
|
|
bad_message_unlock:
|
|
rcu_read_unlock();
|
|
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_LOCAL_ABORT;
|
|
reject_packet:
|
|
trace_rxrpc_rx_done(skb->mark, skb->priority);
|
|
rxrpc_reject_packet(local, skb);
|
|
_leave(" [badmsg]");
|
|
}
|