Use NL_SET_ERR_MSG() and NL_SET_ERR_MSG_FMT() to return meaningful
error messages to the userland whenever a -EOPNOTSUPP error is
returned due to a failed validation of the CAN netlink arguments.
Signed-off-by: Vincent Mailhol <mailhol@kernel.org>
---
drivers/net/can/dev/netlink.c | 82 ++++++++++++++++++++++++++++++++-----------
1 file changed, 62 insertions(+), 20 deletions(-)
diff --git a/drivers/net/can/dev/netlink.c b/drivers/net/can/dev/netlink.c
index 92d8df13e886c8832c4ed8450675c22dc2e5b009..0591406b6f3207f4db5ef1d25dc5e0289a1d06fe 100644
--- a/drivers/net/can/dev/netlink.c
+++ b/drivers/net/can/dev/netlink.c
@@ -64,15 +64,23 @@ static int can_validate_tdc(struct nlattr *data_tdc,
bool tdc_auto = tdc_flags & CAN_CTRLMODE_TDC_AUTO_MASK;
int err;
- /* CAN_CTRLMODE_TDC_{AUTO,MANUAL} are mutually exclusive */
- if (tdc_auto && tdc_manual)
+ if (tdc_auto && tdc_manual) {
+ NL_SET_ERR_MSG(extack,
+ "TDC manual and auto modes are mutually exclusive");
return -EOPNOTSUPP;
+ }
/* If one of the CAN_CTRLMODE_TDC_* flag is set then TDC
* must be set and vice-versa
*/
- if ((tdc_auto || tdc_manual) != !!data_tdc)
+ if ((tdc_auto || tdc_manual) && !data_tdc) {
+ NL_SET_ERR_MSG(extack, "TDC parameters are missing");
return -EOPNOTSUPP;
+ }
+ if (!(tdc_auto || tdc_manual) && data_tdc) {
+ NL_SET_ERR_MSG(extack, "TDC mode (auto or manual) is missing");
+ return -EOPNOTSUPP;
+ }
/* If providing TDC parameters, at least TDCO is needed. TDCV
* is needed if and only if CAN_CTRLMODE_TDC_MANUAL is set
@@ -86,15 +94,23 @@ static int can_validate_tdc(struct nlattr *data_tdc,
return err;
if (tb_tdc[IFLA_CAN_TDC_TDCV]) {
- if (tdc_auto)
+ if (tdc_auto) {
+ NL_SET_ERR_MSG(extack,
+ "TDCV is incompatible with TDC auto mode");
return -EOPNOTSUPP;
+ }
} else {
- if (tdc_manual)
+ if (tdc_manual) {
+ NL_SET_ERR_MSG(extack,
+ "TDC manual mode requires TDCV");
return -EOPNOTSUPP;
+ }
}
- if (!tb_tdc[IFLA_CAN_TDC_TDCO])
+ if (!tb_tdc[IFLA_CAN_TDC_TDCO]) {
+ NL_SET_ERR_MSG(extack, "TDCO is missing");
return -EOPNOTSUPP;
+ }
}
return 0;
@@ -105,6 +121,7 @@ static int can_validate_databittiming(struct nlattr *data[],
int ifla_can_data_bittiming, u32 flags)
{
struct nlattr *data_tdc;
+ const char *type;
u32 tdc_flags;
bool is_on;
int err;
@@ -120,18 +137,31 @@ static int can_validate_databittiming(struct nlattr *data[],
data_tdc = data[IFLA_CAN_TDC];
tdc_flags = flags & CAN_CTRLMODE_FD_TDC_MASK;
is_on = flags & CAN_CTRLMODE_FD;
+ type = "FD";
} else {
return -EOPNOTSUPP; /* Place holder for CAN XL */
}
if (is_on) {
- if (!data[IFLA_CAN_BITTIMING] || !data[ifla_can_data_bittiming])
+ if (!data[IFLA_CAN_BITTIMING] || !data[ifla_can_data_bittiming]) {
+ NL_SET_ERR_MSG_FMT(extack,
+ "Provide both nominal and %s data bittiming",
+ type);
return -EOPNOTSUPP;
- }
-
- if (data[ifla_can_data_bittiming] || data_tdc) {
- if (!is_on)
+ }
+ } else {
+ if (data[ifla_can_data_bittiming]) {
+ NL_SET_ERR_MSG_FMT(extack,
+ "%s data bittiming requires CAN %s",
+ type, type);
return -EOPNOTSUPP;
+ }
+ if (data_tdc) {
+ NL_SET_ERR_MSG_FMT(extack,
+ "%s TDC requires CAN %s",
+ type, type);
+ return -EOPNOTSUPP;
+ }
}
err = can_validate_bittiming(data, extack, ifla_can_data_bittiming);
@@ -178,8 +208,7 @@ static int can_ctrlmode_changelink(struct net_device *dev,
{
struct can_priv *priv = netdev_priv(dev);
struct can_ctrlmode *cm;
- u32 maskedflags;
- u32 ctrlstatic;
+ u32 ctrlstatic, maskedflags, notsupp, ctrlstatic_missing;
if (!data[IFLA_CAN_CTRLMODE])
return 0;
@@ -189,20 +218,28 @@ static int can_ctrlmode_changelink(struct net_device *dev,
return -EBUSY;
cm = nla_data(data[IFLA_CAN_CTRLMODE]);
- maskedflags = cm->flags & cm->mask;
ctrlstatic = can_get_static_ctrlmode(priv);
+ maskedflags = cm->flags & cm->mask;
+ notsupp = maskedflags & ~(priv->ctrlmode_supported | ctrlstatic);
+ ctrlstatic_missing = (maskedflags & ctrlstatic) ^ ctrlstatic;
- /* check whether provided bits are allowed to be passed */
- if (maskedflags & ~(priv->ctrlmode_supported | ctrlstatic))
+ if (notsupp) {
+ NL_SET_ERR_MSG_FMT(extack,
+ "requested control mode %s not supported",
+ can_get_ctrlmode_str(notsupp));
return -EOPNOTSUPP;
+ }
/* do not check for static fd-non-iso if 'fd' is disabled */
if (!(maskedflags & CAN_CTRLMODE_FD))
ctrlstatic &= ~CAN_CTRLMODE_FD_NON_ISO;
- /* make sure static options are provided by configuration */
- if ((maskedflags & ctrlstatic) != ctrlstatic)
+ if (ctrlstatic_missing) {
+ NL_SET_ERR_MSG_FMT(extack,
+ "missing required %s static control mode",
+ can_get_ctrlmode_str(ctrlstatic_missing));
return -EOPNOTSUPP;
+ }
/* If a top dependency flag is provided, reset all its dependencies */
if (cm->mask & CAN_CTRLMODE_FD)
@@ -234,8 +271,10 @@ static int can_tdc_changelink(struct data_bittiming_params *dbt_params,
const struct can_tdc_const *tdc_const = dbt_params->tdc_const;
int err;
- if (!tdc_const)
+ if (!tdc_const) {
+ NL_SET_ERR_MSG(extack, "The device does not support TDC");
return -EOPNOTSUPP;
+ }
err = nla_parse_nested(tb_tdc, IFLA_CAN_TDC_MAX, nla,
can_tdc_policy, extack);
@@ -450,8 +489,11 @@ static int can_changelink(struct net_device *dev, struct nlattr *tb[],
const unsigned int num_term = priv->termination_const_cnt;
unsigned int i;
- if (!priv->do_set_termination)
+ if (!priv->do_set_termination) {
+ NL_SET_ERR_MSG(extack,
+ "Termination is not configurable on this device");
return -EOPNOTSUPP;
+ }
/* check whether given value is supported by the interface */
for (i = 0; i < num_term; i++) {
--
2.49.1