net_sched: reject unknown tcfa_action values

After the commit 802bfb19152c ("net/sched: user-space can't set
unknown tcfa_action values"), unknown tcfa_action values are
converted to TC_ACT_UNSPEC, but the common agreement is instead
rejecting such configurations.

This change also introduces a helper to simplify the destruction
of a single action, avoiding code duplication.

v1 -> v2:
 - helper is now static and renamed according to act_* convention
 - updated extack message, according to the new behavior

Fixes: 802bfb19152c ("net/sched: user-space can't set unknown tcfa_action values")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index db83dac1e7f488cd2fd0d013bce374c5d4123f3c..316c98bb87e4e6bd78aed5c5ea9bf132403f6a8b 100644 (file)
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -662,6 +662,13 @@ int tcf_action_destroy(struct tc_action *actions[], int bind)
        return ret;
 }
 
+static int tcf_action_destroy_1(struct tc_action *a, int bind)
+{
+       struct tc_action *actions[] = { a, NULL };
+
+       return tcf_action_destroy(actions, bind);
+}
+
 static int tcf_action_put(struct tc_action *p)
 {
        return __tcf_action_put(p, false);
@@ -881,17 +888,16 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
        if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN)) {
                err = tcf_action_goto_chain_init(a, tp);
                if (err) {
-                       struct tc_action *actions[] = { a, NULL };
-
-                       tcf_action_destroy(actions, bind);
+                       tcf_action_destroy_1(a, bind);
                        NL_SET_ERR_MSG(extack, "Failed to init TC action chain");
                        return ERR_PTR(err);
                }
        }
 
        if (!tcf_action_valid(a->tcfa_action)) {
-               NL_SET_ERR_MSG(extack, "invalid action value, using TC_ACT_UNSPEC instead");
-               a->tcfa_action = TC_ACT_UNSPEC;
+               tcf_action_destroy_1(a, bind);
+               NL_SET_ERR_MSG(extack, "Invalid control action value");
+               return ERR_PTR(-EINVAL);
        }
 
        return a;