![Colin Ian King](/assets/img/avatar_default.png)
The variable 'len' is being initialized with a value that is never read and it is re-assigned later, hence the initialization is redundant and can be removed. Cleans up clang warning: net/rxrpc/recvmsg.c:275:15: warning: Value stored to 'len' during its initialization is never read Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
714 lines
19 KiB
C
714 lines
19 KiB
C
/* RxRPC recvmsg() implementation
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*
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* Copyright (C) 2007 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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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/net.h>
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#include <linux/skbuff.h>
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#include <linux/export.h>
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#include <linux/sched/signal.h>
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#include <net/sock.h>
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#include <net/af_rxrpc.h>
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#include "ar-internal.h"
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/*
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* Post a call for attention by the socket or kernel service. Further
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* notifications are suppressed by putting recvmsg_link on a dummy queue.
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*/
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void rxrpc_notify_socket(struct rxrpc_call *call)
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{
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struct rxrpc_sock *rx;
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struct sock *sk;
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_enter("%d", call->debug_id);
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if (!list_empty(&call->recvmsg_link))
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return;
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rcu_read_lock();
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rx = rcu_dereference(call->socket);
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sk = &rx->sk;
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if (rx && sk->sk_state < RXRPC_CLOSE) {
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if (call->notify_rx) {
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spin_lock_bh(&call->notify_lock);
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call->notify_rx(sk, call, call->user_call_ID);
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spin_unlock_bh(&call->notify_lock);
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} else {
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write_lock_bh(&rx->recvmsg_lock);
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if (list_empty(&call->recvmsg_link)) {
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rxrpc_get_call(call, rxrpc_call_got);
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list_add_tail(&call->recvmsg_link, &rx->recvmsg_q);
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}
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write_unlock_bh(&rx->recvmsg_lock);
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if (!sock_flag(sk, SOCK_DEAD)) {
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_debug("call %ps", sk->sk_data_ready);
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sk->sk_data_ready(sk);
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}
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}
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}
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rcu_read_unlock();
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_leave("");
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}
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/*
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* Pass a call terminating message to userspace.
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*/
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static int rxrpc_recvmsg_term(struct rxrpc_call *call, struct msghdr *msg)
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{
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u32 tmp = 0;
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int ret;
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switch (call->completion) {
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case RXRPC_CALL_SUCCEEDED:
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ret = 0;
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if (rxrpc_is_service_call(call))
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ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ACK, 0, &tmp);
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break;
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case RXRPC_CALL_REMOTELY_ABORTED:
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tmp = call->abort_code;
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ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ABORT, 4, &tmp);
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break;
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case RXRPC_CALL_LOCALLY_ABORTED:
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tmp = call->abort_code;
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ret = put_cmsg(msg, SOL_RXRPC, RXRPC_ABORT, 4, &tmp);
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break;
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case RXRPC_CALL_NETWORK_ERROR:
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tmp = -call->error;
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ret = put_cmsg(msg, SOL_RXRPC, RXRPC_NET_ERROR, 4, &tmp);
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break;
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case RXRPC_CALL_LOCAL_ERROR:
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tmp = -call->error;
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ret = put_cmsg(msg, SOL_RXRPC, RXRPC_LOCAL_ERROR, 4, &tmp);
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break;
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default:
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pr_err("Invalid terminal call state %u\n", call->state);
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BUG();
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break;
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}
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trace_rxrpc_recvmsg(call, rxrpc_recvmsg_terminal, call->rx_hard_ack,
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call->rx_pkt_offset, call->rx_pkt_len, ret);
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return ret;
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}
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/*
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* Pass back notification of a new call. The call is added to the
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* to-be-accepted list. This means that the next call to be accepted might not
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* be the last call seen awaiting acceptance, but unless we leave this on the
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* front of the queue and block all other messages until someone gives us a
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* user_ID for it, there's not a lot we can do.
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*/
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static int rxrpc_recvmsg_new_call(struct rxrpc_sock *rx,
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struct rxrpc_call *call,
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struct msghdr *msg, int flags)
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{
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int tmp = 0, ret;
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ret = put_cmsg(msg, SOL_RXRPC, RXRPC_NEW_CALL, 0, &tmp);
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if (ret == 0 && !(flags & MSG_PEEK)) {
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_debug("to be accepted");
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write_lock_bh(&rx->recvmsg_lock);
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list_del_init(&call->recvmsg_link);
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write_unlock_bh(&rx->recvmsg_lock);
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rxrpc_get_call(call, rxrpc_call_got);
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write_lock(&rx->call_lock);
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list_add_tail(&call->accept_link, &rx->to_be_accepted);
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write_unlock(&rx->call_lock);
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}
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trace_rxrpc_recvmsg(call, rxrpc_recvmsg_to_be_accepted, 1, 0, 0, ret);
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return ret;
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}
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/*
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* End the packet reception phase.
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*/
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static void rxrpc_end_rx_phase(struct rxrpc_call *call, rxrpc_serial_t serial)
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{
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_enter("%d,%s", call->debug_id, rxrpc_call_states[call->state]);
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trace_rxrpc_receive(call, rxrpc_receive_end, 0, call->rx_top);
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ASSERTCMP(call->rx_hard_ack, ==, call->rx_top);
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#if 0 // TODO: May want to transmit final ACK under some circumstances anyway
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if (call->state == RXRPC_CALL_CLIENT_RECV_REPLY) {
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rxrpc_propose_ACK(call, RXRPC_ACK_IDLE, 0, serial, true, false,
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rxrpc_propose_ack_terminal_ack);
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rxrpc_send_ack_packet(call, false, NULL);
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}
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#endif
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write_lock_bh(&call->state_lock);
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switch (call->state) {
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case RXRPC_CALL_CLIENT_RECV_REPLY:
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__rxrpc_call_completed(call);
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write_unlock_bh(&call->state_lock);
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break;
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case RXRPC_CALL_SERVER_RECV_REQUEST:
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call->tx_phase = true;
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call->state = RXRPC_CALL_SERVER_ACK_REQUEST;
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call->expect_req_by = jiffies + MAX_JIFFY_OFFSET;
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write_unlock_bh(&call->state_lock);
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rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial, false, true,
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rxrpc_propose_ack_processing_op);
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break;
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default:
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write_unlock_bh(&call->state_lock);
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break;
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}
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}
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/*
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* Discard a packet we've used up and advance the Rx window by one.
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*/
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static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
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{
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struct rxrpc_skb_priv *sp;
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struct sk_buff *skb;
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rxrpc_serial_t serial;
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rxrpc_seq_t hard_ack, top;
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u8 flags;
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int ix;
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_enter("%d", call->debug_id);
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hard_ack = call->rx_hard_ack;
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top = smp_load_acquire(&call->rx_top);
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ASSERT(before(hard_ack, top));
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hard_ack++;
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ix = hard_ack & RXRPC_RXTX_BUFF_MASK;
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skb = call->rxtx_buffer[ix];
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rxrpc_see_skb(skb, rxrpc_skb_rx_rotated);
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sp = rxrpc_skb(skb);
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flags = sp->hdr.flags;
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serial = sp->hdr.serial;
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if (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO)
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serial += (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) - 1;
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call->rxtx_buffer[ix] = NULL;
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call->rxtx_annotations[ix] = 0;
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/* Barrier against rxrpc_input_data(). */
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smp_store_release(&call->rx_hard_ack, hard_ack);
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rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
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_debug("%u,%u,%02x", hard_ack, top, flags);
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trace_rxrpc_receive(call, rxrpc_receive_rotate, serial, hard_ack);
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if (flags & RXRPC_LAST_PACKET) {
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rxrpc_end_rx_phase(call, serial);
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} else {
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/* Check to see if there's an ACK that needs sending. */
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if (after_eq(hard_ack, call->ackr_consumed + 2) ||
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after_eq(top, call->ackr_seen + 2) ||
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(hard_ack == top && after(hard_ack, call->ackr_consumed)))
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rxrpc_propose_ACK(call, RXRPC_ACK_DELAY, 0, serial,
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true, true,
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rxrpc_propose_ack_rotate_rx);
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if (call->ackr_reason && call->ackr_reason != RXRPC_ACK_DELAY)
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rxrpc_send_ack_packet(call, false, NULL);
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}
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}
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/*
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* Decrypt and verify a (sub)packet. The packet's length may be changed due to
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* padding, but if this is the case, the packet length will be resident in the
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* socket buffer. Note that we can't modify the master skb info as the skb may
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* be the home to multiple subpackets.
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*/
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static int rxrpc_verify_packet(struct rxrpc_call *call, struct sk_buff *skb,
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u8 annotation,
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unsigned int offset, unsigned int len)
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{
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struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
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rxrpc_seq_t seq = sp->hdr.seq;
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u16 cksum = sp->hdr.cksum;
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_enter("");
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/* For all but the head jumbo subpacket, the security checksum is in a
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* jumbo header immediately prior to the data.
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*/
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if ((annotation & RXRPC_RX_ANNO_JUMBO) > 1) {
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__be16 tmp;
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if (skb_copy_bits(skb, offset - 2, &tmp, 2) < 0)
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BUG();
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cksum = ntohs(tmp);
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seq += (annotation & RXRPC_RX_ANNO_JUMBO) - 1;
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}
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return call->conn->security->verify_packet(call, skb, offset, len,
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seq, cksum);
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}
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/*
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* Locate the data within a packet. This is complicated by:
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*
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* (1) An skb may contain a jumbo packet - so we have to find the appropriate
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* subpacket.
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*
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* (2) The (sub)packets may be encrypted and, if so, the encrypted portion
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* contains an extra header which includes the true length of the data,
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* excluding any encrypted padding.
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*/
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static int rxrpc_locate_data(struct rxrpc_call *call, struct sk_buff *skb,
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u8 *_annotation,
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unsigned int *_offset, unsigned int *_len)
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{
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unsigned int offset = sizeof(struct rxrpc_wire_header);
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unsigned int len;
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int ret;
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u8 annotation = *_annotation;
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/* Locate the subpacket */
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len = skb->len - offset;
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if ((annotation & RXRPC_RX_ANNO_JUMBO) > 0) {
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offset += (((annotation & RXRPC_RX_ANNO_JUMBO) - 1) *
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RXRPC_JUMBO_SUBPKTLEN);
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len = (annotation & RXRPC_RX_ANNO_JLAST) ?
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skb->len - offset : RXRPC_JUMBO_SUBPKTLEN;
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}
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if (!(annotation & RXRPC_RX_ANNO_VERIFIED)) {
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ret = rxrpc_verify_packet(call, skb, annotation, offset, len);
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if (ret < 0)
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return ret;
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*_annotation |= RXRPC_RX_ANNO_VERIFIED;
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}
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*_offset = offset;
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*_len = len;
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call->conn->security->locate_data(call, skb, _offset, _len);
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return 0;
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}
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/*
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* Deliver messages to a call. This keeps processing packets until the buffer
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* is filled and we find either more DATA (returns 0) or the end of the DATA
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* (returns 1). If more packets are required, it returns -EAGAIN.
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*/
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static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
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struct msghdr *msg, struct iov_iter *iter,
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size_t len, int flags, size_t *_offset)
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{
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struct rxrpc_skb_priv *sp;
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struct sk_buff *skb;
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rxrpc_seq_t hard_ack, top, seq;
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size_t remain;
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bool last;
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unsigned int rx_pkt_offset, rx_pkt_len;
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int ix, copy, ret = -EAGAIN, ret2;
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rx_pkt_offset = call->rx_pkt_offset;
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rx_pkt_len = call->rx_pkt_len;
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if (call->state >= RXRPC_CALL_SERVER_ACK_REQUEST) {
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seq = call->rx_hard_ack;
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ret = 1;
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goto done;
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}
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/* Barriers against rxrpc_input_data(). */
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hard_ack = call->rx_hard_ack;
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seq = hard_ack + 1;
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while (top = smp_load_acquire(&call->rx_top),
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before_eq(seq, top)
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) {
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ix = seq & RXRPC_RXTX_BUFF_MASK;
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skb = call->rxtx_buffer[ix];
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if (!skb) {
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trace_rxrpc_recvmsg(call, rxrpc_recvmsg_hole, seq,
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rx_pkt_offset, rx_pkt_len, 0);
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break;
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}
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smp_rmb();
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rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
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sp = rxrpc_skb(skb);
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if (!(flags & MSG_PEEK))
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trace_rxrpc_receive(call, rxrpc_receive_front,
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sp->hdr.serial, seq);
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if (msg)
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sock_recv_timestamp(msg, sock->sk, skb);
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if (rx_pkt_offset == 0) {
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ret2 = rxrpc_locate_data(call, skb,
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&call->rxtx_annotations[ix],
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&rx_pkt_offset, &rx_pkt_len);
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trace_rxrpc_recvmsg(call, rxrpc_recvmsg_next, seq,
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rx_pkt_offset, rx_pkt_len, ret2);
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if (ret2 < 0) {
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ret = ret2;
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goto out;
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}
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} else {
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trace_rxrpc_recvmsg(call, rxrpc_recvmsg_cont, seq,
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rx_pkt_offset, rx_pkt_len, 0);
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}
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/* We have to handle short, empty and used-up DATA packets. */
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remain = len - *_offset;
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copy = rx_pkt_len;
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if (copy > remain)
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copy = remain;
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if (copy > 0) {
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ret2 = skb_copy_datagram_iter(skb, rx_pkt_offset, iter,
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copy);
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if (ret2 < 0) {
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ret = ret2;
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goto out;
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}
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/* handle piecemeal consumption of data packets */
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rx_pkt_offset += copy;
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rx_pkt_len -= copy;
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*_offset += copy;
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}
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if (rx_pkt_len > 0) {
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trace_rxrpc_recvmsg(call, rxrpc_recvmsg_full, seq,
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rx_pkt_offset, rx_pkt_len, 0);
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ASSERTCMP(*_offset, ==, len);
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ret = 0;
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break;
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}
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/* The whole packet has been transferred. */
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last = sp->hdr.flags & RXRPC_LAST_PACKET;
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if (!(flags & MSG_PEEK))
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rxrpc_rotate_rx_window(call);
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rx_pkt_offset = 0;
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rx_pkt_len = 0;
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if (last) {
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ASSERTCMP(seq, ==, READ_ONCE(call->rx_top));
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ret = 1;
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goto out;
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}
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seq++;
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}
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out:
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if (!(flags & MSG_PEEK)) {
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call->rx_pkt_offset = rx_pkt_offset;
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call->rx_pkt_len = rx_pkt_len;
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}
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done:
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trace_rxrpc_recvmsg(call, rxrpc_recvmsg_data_return, seq,
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rx_pkt_offset, rx_pkt_len, ret);
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return ret;
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}
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/*
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* Receive a message from an RxRPC socket
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* - we need to be careful about two or more threads calling recvmsg
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* simultaneously
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*/
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int rxrpc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
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int flags)
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{
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struct rxrpc_call *call;
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struct rxrpc_sock *rx = rxrpc_sk(sock->sk);
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struct list_head *l;
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size_t copied = 0;
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long timeo;
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int ret;
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DEFINE_WAIT(wait);
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trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_enter, 0, 0, 0, 0);
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if (flags & (MSG_OOB | MSG_TRUNC))
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return -EOPNOTSUPP;
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timeo = sock_rcvtimeo(&rx->sk, flags & MSG_DONTWAIT);
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try_again:
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lock_sock(&rx->sk);
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/* Return immediately if a client socket has no outstanding calls */
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if (RB_EMPTY_ROOT(&rx->calls) &&
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list_empty(&rx->recvmsg_q) &&
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rx->sk.sk_state != RXRPC_SERVER_LISTENING) {
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release_sock(&rx->sk);
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return -ENODATA;
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}
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if (list_empty(&rx->recvmsg_q)) {
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ret = -EWOULDBLOCK;
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if (timeo == 0) {
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call = NULL;
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goto error_no_call;
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}
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release_sock(&rx->sk);
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/* Wait for something to happen */
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prepare_to_wait_exclusive(sk_sleep(&rx->sk), &wait,
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TASK_INTERRUPTIBLE);
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ret = sock_error(&rx->sk);
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if (ret)
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goto wait_error;
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if (list_empty(&rx->recvmsg_q)) {
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if (signal_pending(current))
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goto wait_interrupted;
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trace_rxrpc_recvmsg(NULL, rxrpc_recvmsg_wait,
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0, 0, 0, 0);
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timeo = schedule_timeout(timeo);
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}
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finish_wait(sk_sleep(&rx->sk), &wait);
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goto try_again;
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}
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/* Find the next call and dequeue it if we're not just peeking. If we
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* do dequeue it, that comes with a ref that we will need to release.
|
|
*/
|
|
write_lock_bh(&rx->recvmsg_lock);
|
|
l = rx->recvmsg_q.next;
|
|
call = list_entry(l, struct rxrpc_call, recvmsg_link);
|
|
if (!(flags & MSG_PEEK))
|
|
list_del_init(&call->recvmsg_link);
|
|
else
|
|
rxrpc_get_call(call, rxrpc_call_got);
|
|
write_unlock_bh(&rx->recvmsg_lock);
|
|
|
|
trace_rxrpc_recvmsg(call, rxrpc_recvmsg_dequeue, 0, 0, 0, 0);
|
|
|
|
/* We're going to drop the socket lock, so we need to lock the call
|
|
* against interference by sendmsg.
|
|
*/
|
|
if (!mutex_trylock(&call->user_mutex)) {
|
|
ret = -EWOULDBLOCK;
|
|
if (flags & MSG_DONTWAIT)
|
|
goto error_requeue_call;
|
|
ret = -ERESTARTSYS;
|
|
if (mutex_lock_interruptible(&call->user_mutex) < 0)
|
|
goto error_requeue_call;
|
|
}
|
|
|
|
release_sock(&rx->sk);
|
|
|
|
if (test_bit(RXRPC_CALL_RELEASED, &call->flags))
|
|
BUG();
|
|
|
|
if (test_bit(RXRPC_CALL_HAS_USERID, &call->flags)) {
|
|
if (flags & MSG_CMSG_COMPAT) {
|
|
unsigned int id32 = call->user_call_ID;
|
|
|
|
ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID,
|
|
sizeof(unsigned int), &id32);
|
|
} else {
|
|
unsigned long idl = call->user_call_ID;
|
|
|
|
ret = put_cmsg(msg, SOL_RXRPC, RXRPC_USER_CALL_ID,
|
|
sizeof(unsigned long), &idl);
|
|
}
|
|
if (ret < 0)
|
|
goto error_unlock_call;
|
|
}
|
|
|
|
if (msg->msg_name) {
|
|
struct sockaddr_rxrpc *srx = msg->msg_name;
|
|
size_t len = sizeof(call->peer->srx);
|
|
|
|
memcpy(msg->msg_name, &call->peer->srx, len);
|
|
srx->srx_service = call->service_id;
|
|
msg->msg_namelen = len;
|
|
}
|
|
|
|
switch (READ_ONCE(call->state)) {
|
|
case RXRPC_CALL_SERVER_ACCEPTING:
|
|
ret = rxrpc_recvmsg_new_call(rx, call, msg, flags);
|
|
break;
|
|
case RXRPC_CALL_CLIENT_RECV_REPLY:
|
|
case RXRPC_CALL_SERVER_RECV_REQUEST:
|
|
case RXRPC_CALL_SERVER_ACK_REQUEST:
|
|
ret = rxrpc_recvmsg_data(sock, call, msg, &msg->msg_iter, len,
|
|
flags, &copied);
|
|
if (ret == -EAGAIN)
|
|
ret = 0;
|
|
|
|
if (after(call->rx_top, call->rx_hard_ack) &&
|
|
call->rxtx_buffer[(call->rx_hard_ack + 1) & RXRPC_RXTX_BUFF_MASK])
|
|
rxrpc_notify_socket(call);
|
|
break;
|
|
default:
|
|
ret = 0;
|
|
break;
|
|
}
|
|
|
|
if (ret < 0)
|
|
goto error_unlock_call;
|
|
|
|
if (call->state == RXRPC_CALL_COMPLETE) {
|
|
ret = rxrpc_recvmsg_term(call, msg);
|
|
if (ret < 0)
|
|
goto error_unlock_call;
|
|
if (!(flags & MSG_PEEK))
|
|
rxrpc_release_call(rx, call);
|
|
msg->msg_flags |= MSG_EOR;
|
|
ret = 1;
|
|
}
|
|
|
|
if (ret == 0)
|
|
msg->msg_flags |= MSG_MORE;
|
|
else
|
|
msg->msg_flags &= ~MSG_MORE;
|
|
ret = copied;
|
|
|
|
error_unlock_call:
|
|
mutex_unlock(&call->user_mutex);
|
|
rxrpc_put_call(call, rxrpc_call_put);
|
|
trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, 0, 0, 0, ret);
|
|
return ret;
|
|
|
|
error_requeue_call:
|
|
if (!(flags & MSG_PEEK)) {
|
|
write_lock_bh(&rx->recvmsg_lock);
|
|
list_add(&call->recvmsg_link, &rx->recvmsg_q);
|
|
write_unlock_bh(&rx->recvmsg_lock);
|
|
trace_rxrpc_recvmsg(call, rxrpc_recvmsg_requeue, 0, 0, 0, 0);
|
|
} else {
|
|
rxrpc_put_call(call, rxrpc_call_put);
|
|
}
|
|
error_no_call:
|
|
release_sock(&rx->sk);
|
|
trace_rxrpc_recvmsg(call, rxrpc_recvmsg_return, 0, 0, 0, ret);
|
|
return ret;
|
|
|
|
wait_interrupted:
|
|
ret = sock_intr_errno(timeo);
|
|
wait_error:
|
|
finish_wait(sk_sleep(&rx->sk), &wait);
|
|
call = NULL;
|
|
goto error_no_call;
|
|
}
|
|
|
|
/**
|
|
* rxrpc_kernel_recv_data - Allow a kernel service to receive data/info
|
|
* @sock: The socket that the call exists on
|
|
* @call: The call to send data through
|
|
* @buf: The buffer to receive into
|
|
* @size: The size of the buffer, including data already read
|
|
* @_offset: The running offset into the buffer.
|
|
* @want_more: True if more data is expected to be read
|
|
* @_abort: Where the abort code is stored if -ECONNABORTED is returned
|
|
* @_service: Where to store the actual service ID (may be upgraded)
|
|
*
|
|
* Allow a kernel service to receive data and pick up information about the
|
|
* state of a call. Returns 0 if got what was asked for and there's more
|
|
* available, 1 if we got what was asked for and we're at the end of the data
|
|
* and -EAGAIN if we need more data.
|
|
*
|
|
* Note that we may return -EAGAIN to drain empty packets at the end of the
|
|
* data, even if we've already copied over the requested data.
|
|
*
|
|
* This function adds the amount it transfers to *_offset, so this should be
|
|
* precleared as appropriate. Note that the amount remaining in the buffer is
|
|
* taken to be size - *_offset.
|
|
*
|
|
* *_abort should also be initialised to 0.
|
|
*/
|
|
int rxrpc_kernel_recv_data(struct socket *sock, struct rxrpc_call *call,
|
|
void *buf, size_t size, size_t *_offset,
|
|
bool want_more, u32 *_abort, u16 *_service)
|
|
{
|
|
struct iov_iter iter;
|
|
struct kvec iov;
|
|
int ret;
|
|
|
|
_enter("{%d,%s},%zu/%zu,%d",
|
|
call->debug_id, rxrpc_call_states[call->state],
|
|
*_offset, size, want_more);
|
|
|
|
ASSERTCMP(*_offset, <=, size);
|
|
ASSERTCMP(call->state, !=, RXRPC_CALL_SERVER_ACCEPTING);
|
|
|
|
iov.iov_base = buf + *_offset;
|
|
iov.iov_len = size - *_offset;
|
|
iov_iter_kvec(&iter, ITER_KVEC | READ, &iov, 1, size - *_offset);
|
|
|
|
mutex_lock(&call->user_mutex);
|
|
|
|
switch (READ_ONCE(call->state)) {
|
|
case RXRPC_CALL_CLIENT_RECV_REPLY:
|
|
case RXRPC_CALL_SERVER_RECV_REQUEST:
|
|
case RXRPC_CALL_SERVER_ACK_REQUEST:
|
|
ret = rxrpc_recvmsg_data(sock, call, NULL, &iter, size, 0,
|
|
_offset);
|
|
if (ret < 0)
|
|
goto out;
|
|
|
|
/* We can only reach here with a partially full buffer if we
|
|
* have reached the end of the data. We must otherwise have a
|
|
* full buffer or have been given -EAGAIN.
|
|
*/
|
|
if (ret == 1) {
|
|
if (*_offset < size)
|
|
goto short_data;
|
|
if (!want_more)
|
|
goto read_phase_complete;
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
|
|
if (!want_more)
|
|
goto excess_data;
|
|
goto out;
|
|
|
|
case RXRPC_CALL_COMPLETE:
|
|
goto call_complete;
|
|
|
|
default:
|
|
ret = -EINPROGRESS;
|
|
goto out;
|
|
}
|
|
|
|
read_phase_complete:
|
|
ret = 1;
|
|
out:
|
|
if (_service)
|
|
*_service = call->service_id;
|
|
mutex_unlock(&call->user_mutex);
|
|
_leave(" = %d [%zu,%d]", ret, *_offset, *_abort);
|
|
return ret;
|
|
|
|
short_data:
|
|
trace_rxrpc_rx_eproto(call, 0, tracepoint_string("short_data"));
|
|
ret = -EBADMSG;
|
|
goto out;
|
|
excess_data:
|
|
trace_rxrpc_rx_eproto(call, 0, tracepoint_string("excess_data"));
|
|
ret = -EMSGSIZE;
|
|
goto out;
|
|
call_complete:
|
|
*_abort = call->abort_code;
|
|
ret = call->error;
|
|
if (call->completion == RXRPC_CALL_SUCCEEDED) {
|
|
ret = 1;
|
|
if (size > 0)
|
|
ret = -ECONNRESET;
|
|
}
|
|
goto out;
|
|
}
|
|
EXPORT_SYMBOL(rxrpc_kernel_recv_data);
|