can: raw: instantly reject disabled CAN frames

can: raw: instantly reject disabled CAN frames

For real CAN interfaces the CAN_CTRLMODE_FD and CAN_CTRLMODE_XL control
modes indicate whether an interface can handle those CAN FD/XL frames.

In the case a CAN XL interface is configured in CANXL-only mode with
disabled error-signalling neither CAN CC nor CAN FD frames can be sent.

The checks are now performed on CAN_RAW sockets to give an instant feedback
to the user when writing unsupported CAN frames to the interface or when
the CAN interface is in read-only mode.

Fixes: 1a620a723853 ("can: raw: instantly reject unsupported CAN frames")
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Vincent Mailhol <mailhol@kernel.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260109144135.8495-4-socketcan@hartkopp.net
[mkl: fix dev reference leak]
Link: https://lore.kernel.org/all/0636c732-2e71-4633-8005-dfa85e1da445@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>