5.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Oliver Hartkopp socketcan@hartkopp.net
commit b76b163f46b661499921a0049982764a6659bfe7 upstream
With commit 2aa39889c463 ("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: Oliver Hartkopp socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/can/isotp.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-)
--- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -1216,7 +1216,8 @@ static int isotp_bind(struct socket *soc 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;
@@ -1226,24 +1227,28 @@ static int isotp_bind(struct socket *soc if (addr->can_family != AF_CAN) 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; - 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 (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 value */ + if (rx_id != addr->can_addr.tp.rx_id) + return -EINVAL; + } + if (!addr->can_ifindex) return -ENODEV;