linux-brain/include/linux/can/can-ml.h
Oleksij Rempel 4ac1feff6e net: introduce CAN specific pointer in the struct net_device
[ Upstream commit 4e096a18867a5a989b510f6999d9c6b6622e8f7b ]

Since 20dd3850bc ("can: Speed up CAN frame receiption by using
ml_priv") the CAN framework uses per device specific data in the AF_CAN
protocol. For this purpose the struct net_device->ml_priv is used. Later
the ml_priv usage in CAN was extended for other users, one of them being
CAN_J1939.

Later in the kernel ml_priv was converted to an union, used by other
drivers. E.g. the tun driver started storing it's stats pointer.

Since tun devices can claim to be a CAN device, CAN specific protocols
will wrongly interpret this pointer, which will cause system crashes.
Mostly this issue is visible in the CAN_J1939 stack.

To fix this issue, we request a dedicated CAN pointer within the
net_device struct.

Reported-by: syzbot+5138c4dd15a0401bec7b@syzkaller.appspotmail.com
Fixes: 20dd3850bc ("can: Speed up CAN frame receiption by using ml_priv")
Fixes: ffd956eef6 ("can: introduce CAN midlayer private and allocate it automatically")
Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Fixes: 497a5757ce4e ("tun: switch to net core provided statistics counters")
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/r/20210223070127.4538-1-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-04-07 14:47:41 +02:00

81 lines
3.0 KiB
C

/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
/* Copyright (c) 2002-2007 Volkswagen Group Electronic Research
* Copyright (c) 2017 Pengutronix, Marc Kleine-Budde <kernel@pengutronix.de>
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of Volkswagen nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* Alternatively, provided that this notice is retained in full, this
* software may be distributed under the terms of the GNU General
* Public License ("GPL") version 2, in which case the provisions of the
* GPL apply INSTEAD OF those given above.
*
* The provided data structures and external interfaces from this code
* are not restricted to be used by modules with a GPL compatible license.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
*/
#ifndef CAN_ML_H
#define CAN_ML_H
#include <linux/can.h>
#include <linux/list.h>
#include <linux/netdevice.h>
#define CAN_SFF_RCV_ARRAY_SZ (1 << CAN_SFF_ID_BITS)
#define CAN_EFF_RCV_HASH_BITS 10
#define CAN_EFF_RCV_ARRAY_SZ (1 << CAN_EFF_RCV_HASH_BITS)
enum { RX_ERR, RX_ALL, RX_FIL, RX_INV, RX_MAX };
struct can_dev_rcv_lists {
struct hlist_head rx[RX_MAX];
struct hlist_head rx_sff[CAN_SFF_RCV_ARRAY_SZ];
struct hlist_head rx_eff[CAN_EFF_RCV_ARRAY_SZ];
int entries;
};
struct can_ml_priv {
struct can_dev_rcv_lists dev_rcv_lists;
#ifdef CAN_J1939
struct j1939_priv *j1939_priv;
#endif
};
static inline struct can_ml_priv *can_get_ml_priv(struct net_device *dev)
{
return netdev_get_ml_priv(dev, ML_PRIV_CAN);
}
static inline void can_set_ml_priv(struct net_device *dev,
struct can_ml_priv *ml_priv)
{
netdev_set_ml_priv(dev, ml_priv, ML_PRIV_CAN);
}
#endif /* CAN_ML_H */