can: isotp: isotp_setsockopt(): only allow to set low level TX flags for CAN-FD
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@pengutronix.de
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
diff --git a/net/can/isotp.c b/net/can/isotp.c
index 3ef7f78..e32d446 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));