linux/include/net/af_rxrpc.h
David Howells db099c625b rxrpc: Fix timeout of a call that hasn't yet been granted a channel
afs_make_call() calls rxrpc_kernel_begin_call() to begin a call (which may
get stalled in the background waiting for a connection to become
available); it then calls rxrpc_kernel_set_max_life() to set the timeouts -
but that starts the call timer so the call timer might then expire before
we get a connection assigned - leading to the following oops if the call
stalled:

	BUG: kernel NULL pointer dereference, address: 0000000000000000
	...
	CPU: 1 PID: 5111 Comm: krxrpcio/0 Not tainted 6.3.0-rc7-build3+ #701
	RIP: 0010:rxrpc_alloc_txbuf+0xc0/0x157
	...
	Call Trace:
	 <TASK>
	 rxrpc_send_ACK+0x50/0x13b
	 rxrpc_input_call_event+0x16a/0x67d
	 rxrpc_io_thread+0x1b6/0x45f
	 ? _raw_spin_unlock_irqrestore+0x1f/0x35
	 ? rxrpc_input_packet+0x519/0x519
	 kthread+0xe7/0xef
	 ? kthread_complete_and_exit+0x1b/0x1b
	 ret_from_fork+0x22/0x30

Fix this by noting the timeouts in struct rxrpc_call when the call is
created.  The timer will be started when the first packet is transmitted.

It shouldn't be possible to trigger this directly from userspace through
AF_RXRPC as sendmsg() will return EBUSY if the call is in the
waiting-for-conn state if it dropped out of the wait due to a signal.

Fixes: 9d35d880e0 ("rxrpc: Move client call connection to the I/O thread")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: "David S. Miller" <davem@davemloft.net>
cc: Eric Dumazet <edumazet@google.com>
cc: Jakub Kicinski <kuba@kernel.org>
cc: Paolo Abeni <pabeni@redhat.com>
cc: linux-afs@lists.infradead.org
cc: netdev@vger.kernel.org
cc: linux-kernel@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-05-01 07:43:19 +01:00

79 lines
2.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/* RxRPC kernel service interface definitions
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#ifndef _NET_RXRPC_H
#define _NET_RXRPC_H
#include <linux/rxrpc.h>
#include <linux/ktime.h>
struct key;
struct sock;
struct socket;
struct rxrpc_call;
enum rxrpc_abort_reason;
enum rxrpc_interruptibility {
RXRPC_INTERRUPTIBLE, /* Call is interruptible */
RXRPC_PREINTERRUPTIBLE, /* Call can be cancelled whilst waiting for a slot */
RXRPC_UNINTERRUPTIBLE, /* Call should not be interruptible at all */
};
/*
* Debug ID counter for tracing.
*/
extern atomic_t rxrpc_debug_id;
typedef void (*rxrpc_notify_rx_t)(struct sock *, struct rxrpc_call *,
unsigned long);
typedef void (*rxrpc_notify_end_tx_t)(struct sock *, struct rxrpc_call *,
unsigned long);
typedef void (*rxrpc_notify_new_call_t)(struct sock *, struct rxrpc_call *,
unsigned long);
typedef void (*rxrpc_discard_new_call_t)(struct rxrpc_call *, unsigned long);
typedef void (*rxrpc_user_attach_call_t)(struct rxrpc_call *, unsigned long);
void rxrpc_kernel_new_call_notification(struct socket *,
rxrpc_notify_new_call_t,
rxrpc_discard_new_call_t);
struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
struct sockaddr_rxrpc *srx,
struct key *key,
unsigned long user_call_ID,
s64 tx_total_len,
u32 hard_timeout,
gfp_t gfp,
rxrpc_notify_rx_t notify_rx,
bool upgrade,
enum rxrpc_interruptibility interruptibility,
unsigned int debug_id);
int rxrpc_kernel_send_data(struct socket *, struct rxrpc_call *,
struct msghdr *, size_t,
rxrpc_notify_end_tx_t);
int rxrpc_kernel_recv_data(struct socket *, struct rxrpc_call *,
struct iov_iter *, size_t *, bool, u32 *, u16 *);
bool rxrpc_kernel_abort_call(struct socket *, struct rxrpc_call *,
u32, int, enum rxrpc_abort_reason);
void rxrpc_kernel_shutdown_call(struct socket *sock, struct rxrpc_call *call);
void rxrpc_kernel_put_call(struct socket *sock, struct rxrpc_call *call);
void rxrpc_kernel_get_peer(struct socket *, struct rxrpc_call *,
struct sockaddr_rxrpc *);
bool rxrpc_kernel_get_srtt(struct socket *, struct rxrpc_call *, u32 *);
int rxrpc_kernel_charge_accept(struct socket *, rxrpc_notify_rx_t,
rxrpc_user_attach_call_t, unsigned long, gfp_t,
unsigned int);
void rxrpc_kernel_set_tx_length(struct socket *, struct rxrpc_call *, s64);
bool rxrpc_kernel_check_life(const struct socket *, const struct rxrpc_call *);
u32 rxrpc_kernel_get_epoch(struct socket *, struct rxrpc_call *);
void rxrpc_kernel_set_max_life(struct socket *, struct rxrpc_call *,
unsigned long);
int rxrpc_sock_set_min_security_level(struct sock *sk, unsigned int val);
int rxrpc_sock_set_security_keyring(struct sock *, struct key *);
#endif /* _NET_RXRPC_H */