sched: act_ctinfo: use extack error reporting

Use extack error reporting mechanism in addition to returning -EINVAL

NL_SET_ERR_* code shamelessy copy/paste/adjusted from act_pedit &
sch_cake and used as reference as to what I should have done in the
first place.

Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/sched/act_ctinfo.c b/net/sched/act_ctinfo.c
index e78b60e..a7d3679 100644 (file)
--- a/net/sched/act_ctinfo.c
+++ b/net/sched/act_ctinfo.c
@@ -165,15 +165,20 @@ static int tcf_ctinfo_init(struct net *net, struct nlattr *nla,
        u8 dscpmaskshift;
        int ret = 0, err;
 
-       if (!nla)
+       if (!nla) {
+               NL_SET_ERR_MSG_MOD(extack, "ctinfo requires attributes to be passed");
                return -EINVAL;
+       }
 
-       err = nla_parse_nested(tb, TCA_CTINFO_MAX, nla, ctinfo_policy, NULL);
+       err = nla_parse_nested(tb, TCA_CTINFO_MAX, nla, ctinfo_policy, extack);
        if (err < 0)
                return err;
 
-       if (!tb[TCA_CTINFO_ACT])
+       if (!tb[TCA_CTINFO_ACT]) {
+               NL_SET_ERR_MSG_MOD(extack,
+                                  "Missing required TCA_CTINFO_ACT attribute");
                return -EINVAL;
+       }
        actparm = nla_data(tb[TCA_CTINFO_ACT]);
 
        /* do some basic validation here before dynamically allocating things */
@@ -182,13 +187,21 @@ static int tcf_ctinfo_init(struct net *net, struct nlattr *nla,
                dscpmask = nla_get_u32(tb[TCA_CTINFO_PARMS_DSCP_MASK]);
                /* need contiguous 6 bit mask */
                dscpmaskshift = dscpmask ? __ffs(dscpmask) : 0;
-               if ((~0 & (dscpmask >> dscpmaskshift)) != 0x3f)
+               if ((~0 & (dscpmask >> dscpmaskshift)) != 0x3f) {
+                       NL_SET_ERR_MSG_ATTR(extack,
+                                           tb[TCA_CTINFO_PARMS_DSCP_MASK],
+                                           "dscp mask must be 6 contiguous bits");
                        return -EINVAL;
+               }
                dscpstatemask = tb[TCA_CTINFO_PARMS_DSCP_STATEMASK] ?
                        nla_get_u32(tb[TCA_CTINFO_PARMS_DSCP_STATEMASK]) : 0;
                /* mask & statemask must not overlap */
-               if (dscpmask & dscpstatemask)
+               if (dscpmask & dscpstatemask) {
+                       NL_SET_ERR_MSG_ATTR(extack,
+                                           tb[TCA_CTINFO_PARMS_DSCP_STATEMASK],
+                                           "dscp statemask must not overlap dscp mask");
                        return -EINVAL;
+               }
        }
 
        /* done the validation:now to the actual action allocation */