Commit b76b163f authored by Oliver Hartkopp's avatar Oliver Hartkopp Committed by Marc Kleine-Budde
Browse files

can: isotp: isotp_bind(): do not validate unused address information 

With commit 2aa39889 ("can: isotp: isotp_bind(): return -EINVAL on
incorrect CAN ID formatting") the bind() syscall returns -EINVAL when
the given CAN ID needed to be sanitized. But in the case of an unconfirmed
broadcast mode the rx CAN ID is not needed and may be uninitialized from
the caller - which is ok.

This patch makes sure the result of an inproper CAN ID format is only
provided when the address information is needed.

Link: https://lore.kernel.org/all/20220517145653.2556-1-socketcan@hartkopp.net


Signed-off-by: default avatarOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent d7e6f583

net/can/isotp.c

+17 −12
Original line number Diff line number Diff line
@@ -1212,30 +1212,35 @@ static int isotp_bind(struct socket *sock, struct sockaddr *uaddr, int len) 
	struct net *net = sock_net(sk);

	int ifindex;

	struct net_device *dev;

	canid_t tx_id, rx_id;

	canid_t tx_id = addr->can_addr.tp.tx_id;

	canid_t rx_id = addr->can_addr.tp.rx_id;

	int err = 0;

	int notify_enetdown = 0;



	if (len < ISOTP_MIN_NAMELEN)

		return -EINVAL;



	/* sanitize tx/rx CAN identifiers */

	tx_id = addr->can_addr.tp.tx_id;

	/* sanitize tx CAN identifier */

	if (tx_id & CAN_EFF_FLAG)

		tx_id &= (CAN_EFF_FLAG | CAN_EFF_MASK);

	else

		tx_id &= CAN_SFF_MASK;



	rx_id = addr->can_addr.tp.rx_id;

	/* give feedback on wrong CAN-ID value */

	if (tx_id != addr->can_addr.tp.tx_id)

		return -EINVAL;



	/* sanitize rx CAN identifier (if needed) */

	if (isotp_register_rxid(so)) {

		if (rx_id & CAN_EFF_FLAG)

			rx_id &= (CAN_EFF_FLAG | CAN_EFF_MASK);

		else

			rx_id &= CAN_SFF_MASK;



	/* give feedback on wrong CAN-ID values */

	if (tx_id != addr->can_addr.tp.tx_id ||

	    rx_id != addr->can_addr.tp.rx_id)

		/* give feedback on wrong CAN-ID value */

		if (rx_id != addr->can_addr.tp.rx_id)

			return -EINVAL;

	}



	if (!addr->can_ifindex)

		return -ENODEV;