@@ -33,22 +33,38 @@ static int can_fixup_bittiming(const struct net_device *dev, struct can_bittimin
const struct can_bittiming_const *btc,
struct netlink_ext_ack *extack)
{
+ const unsigned int tseg1 = bt->prop_seg + bt->phase_seg1;
const struct can_priv *priv = netdev_priv(dev);
- unsigned int tseg1;
u64 brp64;
int err;
+ if (tseg1 < btc->tseg1_min) {
+ NL_SET_ERR_MSG_FMT(extack, "prop-seg + phase-seg1: %u less than tseg1-min: %u",
+ tseg1, btc->tseg1_min);
+ return -EINVAL;
+ }
+ if (tseg1 > btc->tseg1_max) {
+ NL_SET_ERR_MSG_FMT(extack, "prop-seg + phase-seg1: %u greater than tseg1-max: %u",
+ tseg1, btc->tseg1_max);
+ return -EINVAL;
+ }
+ if (bt->phase_seg2 < btc->tseg2_min) {
+ NL_SET_ERR_MSG_FMT(extack, "phase-seg2: %u less than tseg2-min: %u",
+ bt->phase_seg2, btc->tseg2_min);
+ return -EINVAL;
+ }
+ if (bt->phase_seg2 > btc->tseg2_max) {
+ NL_SET_ERR_MSG_FMT(extack, "phase-seg2: %u greater than tseg2-max: %u",
+ bt->phase_seg2, btc->tseg2_max);
+ return -EINVAL;
+ }
+
can_sjw_set_default(bt);
err = can_sjw_check(dev, bt, btc, extack);
if (err)
return err;
- tseg1 = bt->prop_seg + bt->phase_seg1;
- if (tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max ||
- bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max)
- return -ERANGE;
-
brp64 = (u64)priv->clock.freq * (u64)bt->tq;
if (btc->brp_inc > 1)
do_div(brp64, btc->brp_inc);
@@ -58,8 +74,16 @@ static int can_fixup_bittiming(const struct net_device *dev, struct can_bittimin
brp64 *= btc->brp_inc;
bt->brp = (u32)brp64;
- if (bt->brp < btc->brp_min || bt->brp > btc->brp_max)
+ if (bt->brp < btc->brp_min) {
+ NL_SET_ERR_MSG_FMT(extack, "resulting brp: %u less than brp-min: %u",
+ bt->brp, btc->brp_min);
return -EINVAL;
+ }
+ if (bt->brp > btc->brp_max) {
+ NL_SET_ERR_MSG_FMT(extack, "resulting brp: %u greater than brp-max: %u",
+ bt->brp, btc->brp_max);
+ return -EINVAL;
+ }
bt->bitrate = priv->clock.freq / (bt->brp * can_bit_time(bt));
bt->sample_point = ((CAN_SYNC_SEG + tseg1) * 1000) / can_bit_time(bt);
Check each bit timing parameter first individually against their limits and report a meaningful error message via netlink to the user space. In case of an error, return -EINVAL instead of -ERANGE, this corresponds better to the actual meaning of the error value. Link: https://lore.kernel.org/all/20230202110854.2318594-12-mkl@pengutronix.de Suggested-by: Vincent Mailhol <vincent.mailhol@gmail.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> --- drivers/net/can/dev/bittiming.c | 38 +++++++++++++++++++++++++++------ 1 file changed, 31 insertions(+), 7 deletions(-)