can: bittiming: can_sjw_check(): report error via netlink and harmonize error value

If the user space has supplied an invalid SJW value (greater than the
maximum SJW value), report -EINVAL instead of -ERANGE, this better
matches the actual meaning of the error value.

Additionally report an error message via netlink to the user space.

Link: https://lore.kernel.org/all/20230202110854.2318594-13-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/dev/bittiming.c b/drivers/net/can/dev/bittiming.c
index 727dcd52cc2c40e1e8fc82b8b8a3f377031716ec..0a2a9b12565fddaa100539fa5c1ff7999cd8a8c0 100644 (file)
--- a/drivers/net/can/dev/bittiming.c
+++ b/drivers/net/can/dev/bittiming.c
@@ -18,8 +18,11 @@ void can_sjw_set_default(struct can_bittiming *bt)
 int can_sjw_check(const struct net_device *dev, const struct can_bittiming *bt,
                  const struct can_bittiming_const *btc, struct netlink_ext_ack *extack)
 {
-       if (bt->sjw > btc->sjw_max)
-               return -ERANGE;
+       if (bt->sjw > btc->sjw_max) {
+               NL_SET_ERR_MSG_FMT(extack, "sjw: %u greater than max sjw: %u",
+                                  bt->sjw, btc->sjw_max);
+               return -EINVAL;
+       }
 
        return 0;
 }