can: bittiming: can_sjw_check(): check that SJW is not longer than either Phase Buffer Segment

According to "The Configuration of the CAN Bit Timing" [1] the SJW
"may not be longer than either Phase Buffer Segment".

Check SJW against length of both Phase buffers. In case the SJW is
greater, report an error via netlink to user space and bail out.

[1] http://web.archive.org/http://www.oertel-halle.de/files/cia99paper.pdf

Link: https://lore.kernel.org/all/20230202110854.2318594-14-mkl@pengutronix.deSuggested-by: NVincent Mailhol <vincent.mailhol@gmail.com>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/dev/bittiming.c

@@ -24,6 +24,20 @@ int can_sjw_check(const struct net_device *dev, const struct can_bittiming *bt,
 		return -EINVAL;
 	}
 
+	if (bt->sjw > bt->phase_seg1) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "sjw: %u greater than phase-seg1: %u",
+				   bt->sjw, bt->phase_seg1);
+		return -EINVAL;
+	}
+
+	if (bt->sjw > bt->phase_seg2) {
+		NL_SET_ERR_MSG_FMT(extack,
+				   "sjw: %u greater than phase-seg2: %u",
+				   bt->sjw, bt->phase_seg2);
+		return -EINVAL;
+	}
+
 	return 0;
 }