CAN-FD frames have struct canfd_frame::flags, while classic CAN frames don't. This patch refuses to set TX flags (struct can_isotp_ll_options::tx_flags) on non CAN-FD isotp sockets. Fixes: e057dd3fc20f ("can: add ISO 15765-2:2016 transport protocol") Link: https://lore.kernel.org/r/20210218215434.1708249-2-mkl@xxxxxxxxxxxxxx Cc: Oliver Hartkopp <socketcan@xxxxxxxxxxxx> Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> --- net/can/isotp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/can/isotp.c b/net/can/isotp.c index 3ef7f78e553b..e32d446c121e 100644 --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -1228,7 +1228,8 @@ static int isotp_setsockopt(struct socket *sock, int level, int optname, if (ll.mtu != CAN_MTU && ll.mtu != CANFD_MTU) return -EINVAL; - if (ll.mtu == CAN_MTU && ll.tx_dl > CAN_MAX_DLEN) + if (ll.mtu == CAN_MTU && + (ll.tx_dl > CAN_MAX_DLEN || ll.tx_flags != 0)) return -EINVAL; memcpy(&so->ll, &ll, sizeof(ll)); -- 2.30.1