net: sched: act: handle extack in tcf_generic_walker

This patch adds extack handling for a common used TC act function
"tcf_generic_walker()" to add an extack message on failures.
The tcf_generic_walker() function can fail if get a invalid command
different than DEL and GET. The naming "action" here is wrong, the
correct naming would be command.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/act_api.h

@@ -140,7 +140,8 @@ static inline void tc_action_net_exit(struct list_head *net_list,
 
 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
 		       struct netlink_callback *cb, int type,
-		       const struct tc_action_ops *ops);
+		       const struct tc_action_ops *ops,
+		       struct netlink_ext_ack *extack);
 int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index);
 bool tcf_idr_check(struct tc_action_net *tn, u32 index, struct tc_action **a,
 		    int bind);

net/sched/act_api.c

@@ -202,7 +202,8 @@ static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 
 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
 		       struct netlink_callback *cb, int type,
-		       const struct tc_action_ops *ops)
+		       const struct tc_action_ops *ops,
+		       struct netlink_ext_ack *extack)
 {
 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
 
@@ -211,7 +212,8 @@ int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
 	} else if (type == RTM_GETACTION) {
 		return tcf_dump_walker(idrinfo, skb, cb);
 	} else {
-		WARN(1, "tcf_generic_walker: unknown action %d\n", type);
+		WARN(1, "tcf_generic_walker: unknown command %d\n", type);
+		NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
 		return -EINVAL;
 	}
 }

net/sched/act_bpf.c

@@ -372,7 +372,7 @@ static int tcf_bpf_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, bpf_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_bpf_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_connmark.c

@@ -182,7 +182,7 @@ static int tcf_connmark_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, connmark_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_connmark_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_csum.c

@@ -636,7 +636,7 @@ static int tcf_csum_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, csum_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_csum_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_gact.c

@@ -206,7 +206,7 @@ static int tcf_gact_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, gact_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_gact_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_ife.c

@@ -829,7 +829,7 @@ static int tcf_ife_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, ife_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_ife_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_ipt.c

@@ -308,7 +308,7 @@ static int tcf_ipt_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, ipt_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_ipt_search(struct net *net, struct tc_action **a, u32 index,
@@ -358,7 +358,7 @@ static int tcf_xt_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, xt_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_xt_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_mirred.c

@@ -270,7 +270,7 @@ static int tcf_mirred_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, mirred_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_mirred_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_nat.c

@@ -283,7 +283,7 @@ static int tcf_nat_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, nat_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_nat_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_pedit.c

@@ -424,7 +424,7 @@ static int tcf_pedit_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, pedit_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_pedit_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_police.c

@@ -63,7 +63,7 @@ static int tcf_act_police_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, police_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static const struct nla_policy police_policy[TCA_POLICE_MAX + 1] = {

net/sched/act_sample.c

@@ -207,7 +207,7 @@ static int tcf_sample_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, sample_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_sample_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_simple.c

@@ -175,7 +175,7 @@ static int tcf_simp_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, simp_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_simp_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_skbedit.c

@@ -213,7 +213,7 @@ static int tcf_skbedit_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_skbedit_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_skbmod.c

@@ -237,7 +237,7 @@ static int tcf_skbmod_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, skbmod_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_skbmod_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_tunnel_key.c

@@ -296,7 +296,7 @@ static int tunnel_key_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tunnel_key_search(struct net *net, struct tc_action **a, u32 index,

net/sched/act_vlan.c

@@ -272,7 +272,7 @@ static int tcf_vlan_walker(struct net *net, struct sk_buff *skb,
 {
 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
 
-	return tcf_generic_walker(tn, skb, cb, type, ops);
+	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 }
 
 static int tcf_vlan_search(struct net *net, struct tc_action **a, u32 index,