From 1af85155813622767d223af6d4dff283ebeea7a7 Mon Sep 17 00:00:00 2001
From: Alexander Aring <aring@mojatatu.com>
Date: Thu, 15 Feb 2018 10:54:53 -0500
Subject: [PATCH 1/8] net: sched: act: fix code style

This patch is used by subsequent patches. It fixes code style issues
caught by checkpatch.

Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 include/net/act_api.h  |  5 +++--
 net/sched/act_api.c    | 12 ++++++------
 net/sched/act_mirred.c |  6 +++---
 3 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/include/net/act_api.h b/include/net/act_api.h
index 6ed9692f20bdd..32ef544f4ddcc 100644
--- a/include/net/act_api.h
+++ b/include/net/act_api.h
@@ -87,12 +87,13 @@ struct tc_action_ops {
 		       struct tcf_result *);
 	int     (*dump)(struct sk_buff *, struct tc_action *, int, int);
 	void	(*cleanup)(struct tc_action *);
-	int     (*lookup)(struct net *, struct tc_action **, u32);
+	int     (*lookup)(struct net *net, struct tc_action **a, u32 index);
 	int     (*init)(struct net *net, struct nlattr *nla,
 			struct nlattr *est, struct tc_action **act, int ovr,
 			int bind);
 	int     (*walk)(struct net *, struct sk_buff *,
-			struct netlink_callback *, int, const struct tc_action_ops *);
+			struct netlink_callback *, int,
+			const struct tc_action_ops *);
 	void	(*stats_update)(struct tc_action *, u64, u32, u64);
 	struct net_device *(*get_dev)(const struct tc_action *a);
 };
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index 624995564e5ab..a32e6c2edbf63 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -621,7 +621,7 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 			goto err_out;
 		err = -EINVAL;
 		kind = tb[TCA_ACT_KIND];
-		if (kind == NULL)
+		if (!kind)
 			goto err_out;
 		if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
 			goto err_out;
@@ -822,7 +822,7 @@ static int tca_get_fill(struct sk_buff *skb, struct list_head *actions,
 	t->tca__pad2 = 0;
 
 	nest = nla_nest_start(skb, TCA_ACT_TAB);
-	if (nest == NULL)
+	if (!nest)
 		goto out_nlmsg_trim;
 
 	if (tcf_action_dump(skb, actions, bind, ref) < 0)
@@ -934,7 +934,7 @@ static int tca_action_flush(struct net *net, struct nlattr *nla,
 	t->tca__pad2 = 0;
 
 	nest = nla_nest_start(skb, TCA_ACT_TAB);
-	if (nest == NULL)
+	if (!nest)
 		goto out_module_put;
 
 	err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops);
@@ -1007,10 +1007,10 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
 		return ret;
 
 	if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
-		if (tb[1] != NULL)
+		if (tb[1])
 			return tca_action_flush(net, tb[1], n, portid);
-		else
-			return -EINVAL;
+
+		return -EINVAL;
 	}
 
 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index e6ff88f729009..abcd5f12b9139 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -80,12 +80,12 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
 	bool exists = false;
 	int ret;
 
-	if (nla == NULL)
+	if (!nla)
 		return -EINVAL;
 	ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy, NULL);
 	if (ret < 0)
 		return ret;
-	if (tb[TCA_MIRRED_PARMS] == NULL)
+	if (!tb[TCA_MIRRED_PARMS])
 		return -EINVAL;
 	parm = nla_data(tb[TCA_MIRRED_PARMS]);
 
@@ -117,7 +117,7 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
 	}
 
 	if (!exists) {
-		if (dev == NULL)
+		if (!dev)
 			return -EINVAL;
 		ret = tcf_idr_create(tn, parm->index, est, a,
 				     &act_mirred_ops, bind, true);

From aea0d727899140820a631bac78f36e9d9ef15ef6 Mon Sep 17 00:00:00 2001
From: Alexander Aring <aring@mojatatu.com>
Date: Thu, 15 Feb 2018 10:54:54 -0500
Subject: [PATCH 2/8] net: sched: act: add extack to init

This patch adds extack to tcf_action_init and tcf_action_init_1
functions. These are necessary to make individual extack handling in
each act implementation.

Based on work by David Ahern <dsahern@gmail.com>

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 |  5 +++--
 net/sched/act_api.c   | 17 +++++++++++------
 net/sched/cls_api.c   |  4 ++--
 3 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/include/net/act_api.h b/include/net/act_api.h
index 32ef544f4ddcc..41d95930ffbc8 100644
--- a/include/net/act_api.h
+++ b/include/net/act_api.h
@@ -163,10 +163,11 @@ int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
 		    int nr_actions, struct tcf_result *res);
 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
 		    struct nlattr *est, char *name, int ovr, int bind,
-		    struct list_head *actions);
+		    struct list_head *actions, struct netlink_ext_ack *extack);
 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 				    struct nlattr *nla, struct nlattr *est,
-				    char *name, int ovr, int bind);
+				    char *name, int ovr, int bind,
+				    struct netlink_ext_ack *extack);
 int tcf_action_dump(struct sk_buff *skb, struct list_head *, int, int);
 int tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int, int);
 int tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int, int);
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index a32e6c2edbf63..6625746462569 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -605,7 +605,8 @@ static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
 
 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 				    struct nlattr *nla, struct nlattr *est,
-				    char *name, int ovr, int bind)
+				    char *name, int ovr, int bind,
+				    struct netlink_ext_ack *extack)
 {
 	struct tc_action *a;
 	struct tc_action_ops *a_o;
@@ -726,7 +727,7 @@ static void cleanup_a(struct list_head *actions, int ovr)
 
 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
 		    struct nlattr *est, char *name, int ovr, int bind,
-		    struct list_head *actions)
+		    struct list_head *actions, struct netlink_ext_ack *extack)
 {
 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
 	struct tc_action *act;
@@ -738,7 +739,8 @@ int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
 		return err;
 
 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
-		act = tcf_action_init_1(net, tp, tb[i], est, name, ovr, bind);
+		act = tcf_action_init_1(net, tp, tb[i], est, name, ovr, bind,
+					extack);
 		if (IS_ERR(act)) {
 			err = PTR_ERR(act);
 			goto err;
@@ -1062,12 +1064,14 @@ tcf_add_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
 }
 
 static int tcf_action_add(struct net *net, struct nlattr *nla,
-			  struct nlmsghdr *n, u32 portid, int ovr)
+			  struct nlmsghdr *n, u32 portid, int ovr,
+			  struct netlink_ext_ack *extack)
 {
 	int ret = 0;
 	LIST_HEAD(actions);
 
-	ret = tcf_action_init(net, NULL, nla, NULL, NULL, ovr, 0, &actions);
+	ret = tcf_action_init(net, NULL, nla, NULL, NULL, ovr, 0, &actions,
+			      extack);
 	if (ret)
 		return ret;
 
@@ -1115,7 +1119,8 @@ static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
 		if (n->nlmsg_flags & NLM_F_REPLACE)
 			ovr = 1;
 replay:
-		ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr);
+		ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr,
+				     extack);
 		if (ret == -EAGAIN)
 			goto replay;
 		break;
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 2bc1bc23d42ec..f21610c5da1a2 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -1434,7 +1434,7 @@ int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
 		if (exts->police && tb[exts->police]) {
 			act = tcf_action_init_1(net, tp, tb[exts->police],
 						rate_tlv, "police", ovr,
-						TCA_ACT_BIND);
+						TCA_ACT_BIND, extack);
 			if (IS_ERR(act))
 				return PTR_ERR(act);
 
@@ -1447,7 +1447,7 @@ int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
 
 			err = tcf_action_init(net, tp, tb[exts->action],
 					      rate_tlv, NULL, ovr, TCA_ACT_BIND,
-					      &actions);
+					      &actions, extack);
 			if (err)
 				return err;
 			list_for_each_entry(act, &actions, list)

From 84ae017a00776486390e2c0cceb4f717c3f809c1 Mon Sep 17 00:00:00 2001
From: Alexander Aring <aring@mojatatu.com>
Date: Thu, 15 Feb 2018 10:54:55 -0500
Subject: [PATCH 3/8] net: sched: act: handle generic action errors

This patch adds extack support for generic act handling. The extack
will be set deeper to each called function which is not part of netdev
core api.

Based on work by David Ahern <dsahern@gmail.com>

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/sched/act_api.c | 93 +++++++++++++++++++++++++++++----------------
 1 file changed, 61 insertions(+), 32 deletions(-)

diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index 6625746462569..8e77ddd9f0ad1 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -617,31 +617,40 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 	int err;
 
 	if (name == NULL) {
-		err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, NULL);
+		err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
 		if (err < 0)
 			goto err_out;
 		err = -EINVAL;
 		kind = tb[TCA_ACT_KIND];
-		if (!kind)
+		if (!kind) {
+			NL_SET_ERR_MSG(extack, "TC action kind must be specified");
 			goto err_out;
-		if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
+		}
+		if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ) {
+			NL_SET_ERR_MSG(extack, "TC action name too long");
 			goto err_out;
+		}
 		if (tb[TCA_ACT_COOKIE]) {
 			int cklen = nla_len(tb[TCA_ACT_COOKIE]);
 
-			if (cklen > TC_COOKIE_MAX_SIZE)
+			if (cklen > TC_COOKIE_MAX_SIZE) {
+				NL_SET_ERR_MSG(extack, "TC cookie size above the maximum");
 				goto err_out;
+			}
 
 			cookie = nla_memdup_cookie(tb);
 			if (!cookie) {
+				NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
 				err = -ENOMEM;
 				goto err_out;
 			}
 		}
 	} else {
-		err = -EINVAL;
-		if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
+		if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ) {
+			NL_SET_ERR_MSG(extack, "TC action name too long");
+			err = -EINVAL;
 			goto err_out;
+		}
 	}
 
 	a_o = tc_lookup_action_n(act_name);
@@ -664,6 +673,7 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 			goto err_mod;
 		}
 #endif
+		NL_SET_ERR_MSG(extack, "Failed to load TC action module");
 		err = -ENOENT;
 		goto err_out;
 	}
@@ -698,6 +708,7 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 
 			list_add_tail(&a->list, &actions);
 			tcf_action_destroy(&actions, bind);
+			NL_SET_ERR_MSG(extack, "Failed to init TC action chain");
 			return ERR_PTR(err);
 		}
 	}
@@ -734,7 +745,7 @@ int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
 	int err;
 	int i;
 
-	err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, NULL);
+	err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack);
 	if (err < 0)
 		return err;
 
@@ -842,7 +853,8 @@ static int tca_get_fill(struct sk_buff *skb, struct list_head *actions,
 
 static int
 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
-	       struct list_head *actions, int event)
+	       struct list_head *actions, int event,
+	       struct netlink_ext_ack *extack)
 {
 	struct sk_buff *skb;
 
@@ -851,6 +863,7 @@ tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
 		return -ENOBUFS;
 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
 			 0, 0) <= 0) {
+		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
 		kfree_skb(skb);
 		return -EINVAL;
 	}
@@ -859,7 +872,8 @@ tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
 }
 
 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
-					  struct nlmsghdr *n, u32 portid)
+					  struct nlmsghdr *n, u32 portid,
+					  struct netlink_ext_ack *extack)
 {
 	struct nlattr *tb[TCA_ACT_MAX + 1];
 	const struct tc_action_ops *ops;
@@ -867,20 +881,24 @@ static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
 	int index;
 	int err;
 
-	err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, NULL);
+	err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
 	if (err < 0)
 		goto err_out;
 
 	err = -EINVAL;
 	if (tb[TCA_ACT_INDEX] == NULL ||
-	    nla_len(tb[TCA_ACT_INDEX]) < sizeof(index))
+	    nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
+		NL_SET_ERR_MSG(extack, "Invalid TC action index value");
 		goto err_out;
+	}
 	index = nla_get_u32(tb[TCA_ACT_INDEX]);
 
 	err = -EINVAL;
 	ops = tc_lookup_action(tb[TCA_ACT_KIND]);
-	if (!ops) /* could happen in batch of actions */
+	if (!ops) { /* could happen in batch of actions */
+		NL_SET_ERR_MSG(extack, "Specified TC action not found");
 		goto err_out;
+	}
 	err = -ENOENT;
 	if (ops->lookup(net, &a, index) == 0)
 		goto err_mod;
@@ -895,7 +913,8 @@ static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
 }
 
 static int tca_action_flush(struct net *net, struct nlattr *nla,
-			    struct nlmsghdr *n, u32 portid)
+			    struct nlmsghdr *n, u32 portid,
+			    struct netlink_ext_ack *extack)
 {
 	struct sk_buff *skb;
 	unsigned char *b;
@@ -909,35 +928,39 @@ static int tca_action_flush(struct net *net, struct nlattr *nla,
 	int err = -ENOMEM;
 
 	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
-	if (!skb) {
-		pr_debug("tca_action_flush: failed skb alloc\n");
+	if (!skb)
 		return err;
-	}
 
 	b = skb_tail_pointer(skb);
 
-	err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, NULL);
+	err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
 	if (err < 0)
 		goto err_out;
 
 	err = -EINVAL;
 	kind = tb[TCA_ACT_KIND];
 	ops = tc_lookup_action(kind);
-	if (!ops) /*some idjot trying to flush unknown action */
+	if (!ops) { /*some idjot trying to flush unknown action */
+		NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
 		goto err_out;
+	}
 
 	nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
 			sizeof(*t), 0);
-	if (!nlh)
+	if (!nlh) {
+		NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
 		goto out_module_put;
+	}
 	t = nlmsg_data(nlh);
 	t->tca_family = AF_UNSPEC;
 	t->tca__pad1 = 0;
 	t->tca__pad2 = 0;
 
 	nest = nla_nest_start(skb, TCA_ACT_TAB);
-	if (!nest)
+	if (!nest) {
+		NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
 		goto out_module_put;
+	}
 
 	err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops);
 	if (err <= 0) {
@@ -954,6 +977,8 @@ static int tca_action_flush(struct net *net, struct nlattr *nla,
 			     n->nlmsg_flags & NLM_F_ECHO);
 	if (err > 0)
 		return 0;
+	if (err < 0)
+		NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
 
 	return err;
 
@@ -966,7 +991,7 @@ static int tca_action_flush(struct net *net, struct nlattr *nla,
 
 static int
 tcf_del_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
-	       u32 portid)
+	       u32 portid, struct netlink_ext_ack *extack)
 {
 	int ret;
 	struct sk_buff *skb;
@@ -977,6 +1002,7 @@ tcf_del_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
 
 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
 			 0, 1) <= 0) {
+		NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
 		kfree_skb(skb);
 		return -EINVAL;
 	}
@@ -984,6 +1010,7 @@ tcf_del_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
 	/* now do the delete */
 	ret = tcf_action_destroy(actions, 0);
 	if (ret < 0) {
+		NL_SET_ERR_MSG(extack, "Failed to delete TC action");
 		kfree_skb(skb);
 		return ret;
 	}
@@ -997,26 +1024,27 @@ tcf_del_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
 
 static int
 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
-	      u32 portid, int event)
+	      u32 portid, int event, struct netlink_ext_ack *extack)
 {
 	int i, ret;
 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
 	struct tc_action *act;
 	LIST_HEAD(actions);
 
-	ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, NULL);
+	ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack);
 	if (ret < 0)
 		return ret;
 
 	if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
 		if (tb[1])
-			return tca_action_flush(net, tb[1], n, portid);
+			return tca_action_flush(net, tb[1], n, portid, extack);
 
+		NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
 		return -EINVAL;
 	}
 
 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
-		act = tcf_action_get_1(net, tb[i], n, portid);
+		act = tcf_action_get_1(net, tb[i], n, portid, extack);
 		if (IS_ERR(act)) {
 			ret = PTR_ERR(act);
 			goto err;
@@ -1026,9 +1054,9 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
 	}
 
 	if (event == RTM_GETACTION)
-		ret = tcf_get_notify(net, portid, n, &actions, event);
+		ret = tcf_get_notify(net, portid, n, &actions, event, extack);
 	else { /* delete */
-		ret = tcf_del_notify(net, n, &actions, portid);
+		ret = tcf_del_notify(net, n, &actions, portid, extack);
 		if (ret)
 			goto err;
 		return ret;
@@ -1041,7 +1069,7 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
 
 static int
 tcf_add_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
-	       u32 portid)
+	       u32 portid, struct netlink_ext_ack *extack)
 {
 	struct sk_buff *skb;
 	int err = 0;
@@ -1052,6 +1080,7 @@ tcf_add_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
 
 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
 			 RTM_NEWACTION, 0, 0) <= 0) {
+		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while deleting TC action");
 		kfree_skb(skb);
 		return -EINVAL;
 	}
@@ -1075,7 +1104,7 @@ static int tcf_action_add(struct net *net, struct nlattr *nla,
 	if (ret)
 		return ret;
 
-	return tcf_add_notify(net, n, &actions, portid);
+	return tcf_add_notify(net, n, &actions, portid, extack);
 }
 
 static u32 tcaa_root_flags_allowed = TCA_FLAG_LARGE_DUMP_ON;
@@ -1103,7 +1132,7 @@ static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
 		return ret;
 
 	if (tca[TCA_ACT_TAB] == NULL) {
-		pr_notice("tc_ctl_action: received NO action attribs\n");
+		NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
 		return -EINVAL;
 	}
 
@@ -1126,11 +1155,11 @@ static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
 		break;
 	case RTM_DELACTION:
 		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
-				    portid, RTM_DELACTION);
+				    portid, RTM_DELACTION, extack);
 		break;
 	case RTM_GETACTION:
 		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
-				    portid, RTM_GETACTION);
+				    portid, RTM_GETACTION, extack);
 		break;
 	default:
 		BUG();

From 589dad6d71a72dd7912e5070c63f6bf1f561b5cf Mon Sep 17 00:00:00 2001
From: Alexander Aring <aring@mojatatu.com>
Date: Thu, 15 Feb 2018 10:54:56 -0500
Subject: [PATCH 4/8] net: sched: act: add extack to init callback

This patch adds extack support for act init callback api. This
prepares to handle extack support inside each specific act
implementation.

Based on work by David Ahern <dsahern@gmail.com>

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      | 2 +-
 net/sched/act_api.c        | 5 +++--
 net/sched/act_bpf.c        | 2 +-
 net/sched/act_connmark.c   | 3 ++-
 net/sched/act_csum.c       | 2 +-
 net/sched/act_gact.c       | 2 +-
 net/sched/act_ife.c        | 2 +-
 net/sched/act_ipt.c        | 4 ++--
 net/sched/act_mirred.c     | 2 +-
 net/sched/act_nat.c        | 3 ++-
 net/sched/act_pedit.c      | 2 +-
 net/sched/act_police.c     | 3 ++-
 net/sched/act_sample.c     | 2 +-
 net/sched/act_simple.c     | 2 +-
 net/sched/act_skbedit.c    | 2 +-
 net/sched/act_skbmod.c     | 2 +-
 net/sched/act_tunnel_key.c | 2 +-
 net/sched/act_vlan.c       | 2 +-
 18 files changed, 24 insertions(+), 20 deletions(-)

diff --git a/include/net/act_api.h b/include/net/act_api.h
index 41d95930ffbc8..3717e0f2bb1b7 100644
--- a/include/net/act_api.h
+++ b/include/net/act_api.h
@@ -90,7 +90,7 @@ struct tc_action_ops {
 	int     (*lookup)(struct net *net, struct tc_action **a, u32 index);
 	int     (*init)(struct net *net, struct nlattr *nla,
 			struct nlattr *est, struct tc_action **act, int ovr,
-			int bind);
+			int bind, struct netlink_ext_ack *extack);
 	int     (*walk)(struct net *, struct sk_buff *,
 			struct netlink_callback *, int,
 			const struct tc_action_ops *);
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index 8e77ddd9f0ad1..576a0c311e5ee 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -680,9 +680,10 @@ struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 
 	/* backward compatibility for policer */
 	if (name == NULL)
-		err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind);
+		err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind,
+				extack);
 	else
-		err = a_o->init(net, nla, est, &a, ovr, bind);
+		err = a_o->init(net, nla, est, &a, ovr, bind, extack);
 	if (err < 0)
 		goto err_mod;
 
diff --git a/net/sched/act_bpf.c b/net/sched/act_bpf.c
index b3f2c15affa7b..b3ebfa9598e2d 100644
--- a/net/sched/act_bpf.c
+++ b/net/sched/act_bpf.c
@@ -272,7 +272,7 @@ static void tcf_bpf_prog_fill_cfg(const struct tcf_bpf *prog,
 
 static int tcf_bpf_init(struct net *net, struct nlattr *nla,
 			struct nlattr *est, struct tc_action **act,
-			int replace, int bind)
+			int replace, int bind, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, bpf_net_id);
 	struct nlattr *tb[TCA_ACT_BPF_MAX + 1];
diff --git a/net/sched/act_connmark.c b/net/sched/act_connmark.c
index 2b15ba84e0c8e..20e0215360b50 100644
--- a/net/sched/act_connmark.c
+++ b/net/sched/act_connmark.c
@@ -96,7 +96,8 @@ static const struct nla_policy connmark_policy[TCA_CONNMARK_MAX + 1] = {
 
 static int tcf_connmark_init(struct net *net, struct nlattr *nla,
 			     struct nlattr *est, struct tc_action **a,
-			     int ovr, int bind)
+			     int ovr, int bind,
+			     struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, connmark_net_id);
 	struct nlattr *tb[TCA_CONNMARK_MAX + 1];
diff --git a/net/sched/act_csum.c b/net/sched/act_csum.c
index b7ba9b06b147e..3b8c48bb2683b 100644
--- a/net/sched/act_csum.c
+++ b/net/sched/act_csum.c
@@ -46,7 +46,7 @@ static struct tc_action_ops act_csum_ops;
 
 static int tcf_csum_init(struct net *net, struct nlattr *nla,
 			 struct nlattr *est, struct tc_action **a, int ovr,
-			 int bind)
+			 int bind, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, csum_net_id);
 	struct tcf_csum_params *params_old, *params_new;
diff --git a/net/sched/act_gact.c b/net/sched/act_gact.c
index b56986d41c87f..912f3398f1c1a 100644
--- a/net/sched/act_gact.c
+++ b/net/sched/act_gact.c
@@ -56,7 +56,7 @@ static const struct nla_policy gact_policy[TCA_GACT_MAX + 1] = {
 
 static int tcf_gact_init(struct net *net, struct nlattr *nla,
 			 struct nlattr *est, struct tc_action **a,
-			 int ovr, int bind)
+			 int ovr, int bind, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, gact_net_id);
 	struct nlattr *tb[TCA_GACT_MAX + 1];
diff --git a/net/sched/act_ife.c b/net/sched/act_ife.c
index 5954e992685a0..e5127d4007371 100644
--- a/net/sched/act_ife.c
+++ b/net/sched/act_ife.c
@@ -447,7 +447,7 @@ static int populate_metalist(struct tcf_ife_info *ife, struct nlattr **tb,
 
 static int tcf_ife_init(struct net *net, struct nlattr *nla,
 			struct nlattr *est, struct tc_action **a,
-			int ovr, int bind)
+			int ovr, int bind, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, ife_net_id);
 	struct nlattr *tb[TCA_IFE_MAX + 1];
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
index 06e380ae09283..6894cfa838638 100644
--- a/net/sched/act_ipt.c
+++ b/net/sched/act_ipt.c
@@ -193,7 +193,7 @@ static int __tcf_ipt_init(struct net *net, unsigned int id, struct nlattr *nla,
 
 static int tcf_ipt_init(struct net *net, struct nlattr *nla,
 			struct nlattr *est, struct tc_action **a, int ovr,
-			int bind)
+			int bind, struct netlink_ext_ack *extack)
 {
 	return __tcf_ipt_init(net, ipt_net_id, nla, est, a, &act_ipt_ops, ovr,
 			      bind);
@@ -201,7 +201,7 @@ static int tcf_ipt_init(struct net *net, struct nlattr *nla,
 
 static int tcf_xt_init(struct net *net, struct nlattr *nla,
 		       struct nlattr *est, struct tc_action **a, int ovr,
-		       int bind)
+		       int bind, struct netlink_ext_ack *extack)
 {
 	return __tcf_ipt_init(net, xt_net_id, nla, est, a, &act_xt_ops, ovr,
 			      bind);
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index abcd5f12b9139..7ccd4c71179f0 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -69,7 +69,7 @@ static struct tc_action_ops act_mirred_ops;
 
 static int tcf_mirred_init(struct net *net, struct nlattr *nla,
 			   struct nlattr *est, struct tc_action **a, int ovr,
-			   int bind)
+			   int bind, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, mirred_net_id);
 	struct nlattr *tb[TCA_MIRRED_MAX + 1];
diff --git a/net/sched/act_nat.c b/net/sched/act_nat.c
index 98c6a4b2f5238..7e5ebd7f52a62 100644
--- a/net/sched/act_nat.c
+++ b/net/sched/act_nat.c
@@ -37,7 +37,8 @@ static const struct nla_policy nat_policy[TCA_NAT_MAX + 1] = {
 };
 
 static int tcf_nat_init(struct net *net, struct nlattr *nla, struct nlattr *est,
-			struct tc_action **a, int ovr, int bind)
+			struct tc_action **a, int ovr, int bind,
+			struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, nat_net_id);
 	struct nlattr *tb[TCA_NAT_MAX + 1];
diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c
index 349beaffb29e4..bb2c35ed6f100 100644
--- a/net/sched/act_pedit.c
+++ b/net/sched/act_pedit.c
@@ -132,7 +132,7 @@ static int tcf_pedit_key_ex_dump(struct sk_buff *skb,
 
 static int tcf_pedit_init(struct net *net, struct nlattr *nla,
 			  struct nlattr *est, struct tc_action **a,
-			  int ovr, int bind)
+			  int ovr, int bind, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, pedit_net_id);
 	struct nlattr *tb[TCA_PEDIT_MAX + 1];
diff --git a/net/sched/act_police.c b/net/sched/act_police.c
index 95d3c9097b251..6b6facbe251be 100644
--- a/net/sched/act_police.c
+++ b/net/sched/act_police.c
@@ -74,7 +74,8 @@ static const struct nla_policy police_policy[TCA_POLICE_MAX + 1] = {
 
 static int tcf_act_police_init(struct net *net, struct nlattr *nla,
 			       struct nlattr *est, struct tc_action **a,
-			       int ovr, int bind)
+			       int ovr, int bind,
+			       struct netlink_ext_ack *extack)
 {
 	int ret = 0, err;
 	struct nlattr *tb[TCA_POLICE_MAX + 1];
diff --git a/net/sched/act_sample.c b/net/sched/act_sample.c
index 1ba0df2387562..f4579ceba1f64 100644
--- a/net/sched/act_sample.c
+++ b/net/sched/act_sample.c
@@ -37,7 +37,7 @@ static const struct nla_policy sample_policy[TCA_SAMPLE_MAX + 1] = {
 
 static int tcf_sample_init(struct net *net, struct nlattr *nla,
 			   struct nlattr *est, struct tc_action **a, int ovr,
-			   int bind)
+			   int bind, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, sample_net_id);
 	struct nlattr *tb[TCA_SAMPLE_MAX + 1];
diff --git a/net/sched/act_simple.c b/net/sched/act_simple.c
index 425eac11f6da0..b0346347c5f07 100644
--- a/net/sched/act_simple.c
+++ b/net/sched/act_simple.c
@@ -79,7 +79,7 @@ static const struct nla_policy simple_policy[TCA_DEF_MAX + 1] = {
 
 static int tcf_simp_init(struct net *net, struct nlattr *nla,
 			 struct nlattr *est, struct tc_action **a,
-			 int ovr, int bind)
+			 int ovr, int bind, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, simp_net_id);
 	struct nlattr *tb[TCA_DEF_MAX + 1];
diff --git a/net/sched/act_skbedit.c b/net/sched/act_skbedit.c
index 5a3f691bb5455..7651c9d2182da 100644
--- a/net/sched/act_skbedit.c
+++ b/net/sched/act_skbedit.c
@@ -66,7 +66,7 @@ static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
 
 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
 			    struct nlattr *est, struct tc_action **a,
-			    int ovr, int bind)
+			    int ovr, int bind, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 	struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
diff --git a/net/sched/act_skbmod.c b/net/sched/act_skbmod.c
index fa975262dbacf..1266449aa8ea4 100644
--- a/net/sched/act_skbmod.c
+++ b/net/sched/act_skbmod.c
@@ -84,7 +84,7 @@ static const struct nla_policy skbmod_policy[TCA_SKBMOD_MAX + 1] = {
 
 static int tcf_skbmod_init(struct net *net, struct nlattr *nla,
 			   struct nlattr *est, struct tc_action **a,
-			   int ovr, int bind)
+			   int ovr, int bind, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, skbmod_net_id);
 	struct nlattr *tb[TCA_SKBMOD_MAX + 1];
diff --git a/net/sched/act_tunnel_key.c b/net/sched/act_tunnel_key.c
index 0e23aac09ad63..dde01eca7ed05 100644
--- a/net/sched/act_tunnel_key.c
+++ b/net/sched/act_tunnel_key.c
@@ -70,7 +70,7 @@ static const struct nla_policy tunnel_key_policy[TCA_TUNNEL_KEY_MAX + 1] = {
 
 static int tunnel_key_init(struct net *net, struct nlattr *nla,
 			   struct nlattr *est, struct tc_action **a,
-			   int ovr, int bind)
+			   int ovr, int bind, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
 	struct nlattr *tb[TCA_TUNNEL_KEY_MAX + 1];
diff --git a/net/sched/act_vlan.c b/net/sched/act_vlan.c
index e1a1b3f3983a6..6c387310b1b69 100644
--- a/net/sched/act_vlan.c
+++ b/net/sched/act_vlan.c
@@ -109,7 +109,7 @@ static const struct nla_policy vlan_policy[TCA_VLAN_MAX + 1] = {
 
 static int tcf_vlan_init(struct net *net, struct nlattr *nla,
 			 struct nlattr *est, struct tc_action **a,
-			 int ovr, int bind)
+			 int ovr, int bind, struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
 	struct nlattr *tb[TCA_VLAN_MAX + 1];

From 331a9295de23a9428adb7f593d0701d393a2079e Mon Sep 17 00:00:00 2001
From: Alexander Aring <aring@mojatatu.com>
Date: Thu, 15 Feb 2018 10:54:57 -0500
Subject: [PATCH 5/8] net: sched: act: add extack for lookup callback

This patch adds extack support for act lookup callback api. This
prepares to handle extack support inside each specific act
implementation.

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      | 3 ++-
 net/sched/act_api.c        | 2 +-
 net/sched/act_bpf.c        | 3 ++-
 net/sched/act_connmark.c   | 3 ++-
 net/sched/act_csum.c       | 3 ++-
 net/sched/act_gact.c       | 3 ++-
 net/sched/act_ife.c        | 3 ++-
 net/sched/act_ipt.c        | 6 ++++--
 net/sched/act_mirred.c     | 3 ++-
 net/sched/act_nat.c        | 3 ++-
 net/sched/act_pedit.c      | 3 ++-
 net/sched/act_police.c     | 3 ++-
 net/sched/act_sample.c     | 3 ++-
 net/sched/act_simple.c     | 3 ++-
 net/sched/act_skbedit.c    | 3 ++-
 net/sched/act_skbmod.c     | 3 ++-
 net/sched/act_tunnel_key.c | 3 ++-
 net/sched/act_vlan.c       | 3 ++-
 18 files changed, 37 insertions(+), 19 deletions(-)

diff --git a/include/net/act_api.h b/include/net/act_api.h
index 3717e0f2bb1b7..0bd65db506bae 100644
--- a/include/net/act_api.h
+++ b/include/net/act_api.h
@@ -87,7 +87,8 @@ struct tc_action_ops {
 		       struct tcf_result *);
 	int     (*dump)(struct sk_buff *, struct tc_action *, int, int);
 	void	(*cleanup)(struct tc_action *);
-	int     (*lookup)(struct net *net, struct tc_action **a, u32 index);
+	int     (*lookup)(struct net *net, struct tc_action **a, u32 index,
+			  struct netlink_ext_ack *extack);
 	int     (*init)(struct net *net, struct nlattr *nla,
 			struct nlattr *est, struct tc_action **act, int ovr,
 			int bind, struct netlink_ext_ack *extack);
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index 576a0c311e5ee..74ed1e288e57f 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -901,7 +901,7 @@ static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
 		goto err_out;
 	}
 	err = -ENOENT;
-	if (ops->lookup(net, &a, index) == 0)
+	if (ops->lookup(net, &a, index, extack) == 0)
 		goto err_mod;
 
 	module_put(ops->owner);
diff --git a/net/sched/act_bpf.c b/net/sched/act_bpf.c
index b3ebfa9598e2d..d9654b8633479 100644
--- a/net/sched/act_bpf.c
+++ b/net/sched/act_bpf.c
@@ -374,7 +374,8 @@ static int tcf_bpf_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_bpf_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_bpf_search(struct net *net, struct tc_action **a, u32 index,
+			  struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, bpf_net_id);
 
diff --git a/net/sched/act_connmark.c b/net/sched/act_connmark.c
index 20e0215360b50..0504b7600fb6b 100644
--- a/net/sched/act_connmark.c
+++ b/net/sched/act_connmark.c
@@ -184,7 +184,8 @@ static int tcf_connmark_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_connmark_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_connmark_search(struct net *net, struct tc_action **a, u32 index,
+			       struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, connmark_net_id);
 
diff --git a/net/sched/act_csum.c b/net/sched/act_csum.c
index 3b8c48bb2683b..bdd17b9ef0342 100644
--- a/net/sched/act_csum.c
+++ b/net/sched/act_csum.c
@@ -638,7 +638,8 @@ static int tcf_csum_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_csum_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_csum_search(struct net *net, struct tc_action **a, u32 index,
+			   struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, csum_net_id);
 
diff --git a/net/sched/act_gact.c b/net/sched/act_gact.c
index 912f3398f1c1a..e1e69e38f4b00 100644
--- a/net/sched/act_gact.c
+++ b/net/sched/act_gact.c
@@ -208,7 +208,8 @@ static int tcf_gact_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_gact_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_gact_search(struct net *net, struct tc_action **a, u32 index,
+			   struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, gact_net_id);
 
diff --git a/net/sched/act_ife.c b/net/sched/act_ife.c
index e5127d4007371..0b70fb0cc6096 100644
--- a/net/sched/act_ife.c
+++ b/net/sched/act_ife.c
@@ -831,7 +831,8 @@ static int tcf_ife_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_ife_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_ife_search(struct net *net, struct tc_action **a, u32 index,
+			  struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, ife_net_id);
 
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
index 6894cfa838638..f29af79a2d1f9 100644
--- a/net/sched/act_ipt.c
+++ b/net/sched/act_ipt.c
@@ -310,7 +310,8 @@ static int tcf_ipt_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_ipt_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_ipt_search(struct net *net, struct tc_action **a, u32 index,
+			  struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, ipt_net_id);
 
@@ -358,7 +359,8 @@ static int tcf_xt_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_xt_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_xt_search(struct net *net, struct tc_action **a, u32 index,
+			 struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, xt_net_id);
 
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index 7ccd4c71179f0..9980c6affb5e2 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -272,7 +272,8 @@ static int tcf_mirred_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_mirred_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_mirred_search(struct net *net, struct tc_action **a, u32 index,
+			     struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, mirred_net_id);
 
diff --git a/net/sched/act_nat.c b/net/sched/act_nat.c
index 7e5ebd7f52a62..6f6d7667ef9a8 100644
--- a/net/sched/act_nat.c
+++ b/net/sched/act_nat.c
@@ -285,7 +285,8 @@ static int tcf_nat_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_nat_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_nat_search(struct net *net, struct tc_action **a, u32 index,
+			  struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, nat_net_id);
 
diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c
index bb2c35ed6f100..308b2680a6d9a 100644
--- a/net/sched/act_pedit.c
+++ b/net/sched/act_pedit.c
@@ -426,7 +426,8 @@ static int tcf_pedit_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_pedit_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_pedit_search(struct net *net, struct tc_action **a, u32 index,
+			    struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, pedit_net_id);
 
diff --git a/net/sched/act_police.c b/net/sched/act_police.c
index 6b6facbe251be..1292f880eab00 100644
--- a/net/sched/act_police.c
+++ b/net/sched/act_police.c
@@ -305,7 +305,8 @@ static int tcf_act_police_dump(struct sk_buff *skb, struct tc_action *a,
 	return -1;
 }
 
-static int tcf_police_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_police_search(struct net *net, struct tc_action **a, u32 index,
+			     struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, police_net_id);
 
diff --git a/net/sched/act_sample.c b/net/sched/act_sample.c
index f4579ceba1f64..22379b2cfd1a0 100644
--- a/net/sched/act_sample.c
+++ b/net/sched/act_sample.c
@@ -209,7 +209,8 @@ static int tcf_sample_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_sample_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_sample_search(struct net *net, struct tc_action **a, u32 index,
+			     struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, sample_net_id);
 
diff --git a/net/sched/act_simple.c b/net/sched/act_simple.c
index b0346347c5f07..3ebf714709774 100644
--- a/net/sched/act_simple.c
+++ b/net/sched/act_simple.c
@@ -177,7 +177,8 @@ static int tcf_simp_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_simp_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_simp_search(struct net *net, struct tc_action **a, u32 index,
+			   struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, simp_net_id);
 
diff --git a/net/sched/act_skbedit.c b/net/sched/act_skbedit.c
index 7651c9d2182da..ff1970e140168 100644
--- a/net/sched/act_skbedit.c
+++ b/net/sched/act_skbedit.c
@@ -215,7 +215,8 @@ static int tcf_skbedit_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_skbedit_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_skbedit_search(struct net *net, struct tc_action **a, u32 index,
+			      struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, skbedit_net_id);
 
diff --git a/net/sched/act_skbmod.c b/net/sched/act_skbmod.c
index 1266449aa8ea4..110d7c1f823da 100644
--- a/net/sched/act_skbmod.c
+++ b/net/sched/act_skbmod.c
@@ -239,7 +239,8 @@ static int tcf_skbmod_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_skbmod_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_skbmod_search(struct net *net, struct tc_action **a, u32 index,
+			     struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, skbmod_net_id);
 
diff --git a/net/sched/act_tunnel_key.c b/net/sched/act_tunnel_key.c
index dde01eca7ed05..65a19928f1a94 100644
--- a/net/sched/act_tunnel_key.c
+++ b/net/sched/act_tunnel_key.c
@@ -298,7 +298,8 @@ static int tunnel_key_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tunnel_key_search(struct net *net, struct tc_action **a, u32 index)
+static int tunnel_key_search(struct net *net, struct tc_action **a, u32 index,
+			     struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, tunnel_key_net_id);
 
diff --git a/net/sched/act_vlan.c b/net/sched/act_vlan.c
index 6c387310b1b69..03dcbbc5ffd2c 100644
--- a/net/sched/act_vlan.c
+++ b/net/sched/act_vlan.c
@@ -274,7 +274,8 @@ static int tcf_vlan_walker(struct net *net, struct sk_buff *skb,
 	return tcf_generic_walker(tn, skb, cb, type, ops);
 }
 
-static int tcf_vlan_search(struct net *net, struct tc_action **a, u32 index)
+static int tcf_vlan_search(struct net *net, struct tc_action **a, u32 index,
+			   struct netlink_ext_ack *extack)
 {
 	struct tc_action_net *tn = net_generic(net, vlan_net_id);
 

From 417801055b8cb4c052e989289ccf24a673178bbc Mon Sep 17 00:00:00 2001
From: Alexander Aring <aring@mojatatu.com>
Date: Thu, 15 Feb 2018 10:54:58 -0500
Subject: [PATCH 6/8] net: sched: act: add extack for walk callback

This patch adds extack support for act walker callback api. This
prepares to handle extack support inside each specific act
implementation.

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      | 3 ++-
 net/sched/act_api.c        | 4 ++--
 net/sched/act_bpf.c        | 3 ++-
 net/sched/act_connmark.c   | 3 ++-
 net/sched/act_csum.c       | 3 ++-
 net/sched/act_gact.c       | 3 ++-
 net/sched/act_ife.c        | 3 ++-
 net/sched/act_ipt.c        | 6 ++++--
 net/sched/act_mirred.c     | 3 ++-
 net/sched/act_nat.c        | 3 ++-
 net/sched/act_pedit.c      | 3 ++-
 net/sched/act_police.c     | 3 ++-
 net/sched/act_sample.c     | 3 ++-
 net/sched/act_simple.c     | 3 ++-
 net/sched/act_skbedit.c    | 3 ++-
 net/sched/act_skbmod.c     | 3 ++-
 net/sched/act_tunnel_key.c | 3 ++-
 net/sched/act_vlan.c       | 3 ++-
 18 files changed, 38 insertions(+), 20 deletions(-)

diff --git a/include/net/act_api.h b/include/net/act_api.h
index 0bd65db506bae..ab35292553774 100644
--- a/include/net/act_api.h
+++ b/include/net/act_api.h
@@ -94,7 +94,8 @@ struct tc_action_ops {
 			int bind, struct netlink_ext_ack *extack);
 	int     (*walk)(struct net *, struct sk_buff *,
 			struct netlink_callback *, int,
-			const struct tc_action_ops *);
+			const struct tc_action_ops *,
+			struct netlink_ext_ack *);
 	void	(*stats_update)(struct tc_action *, u64, u32, u64);
 	struct net_device *(*get_dev)(const struct tc_action *a);
 };
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index 74ed1e288e57f..ab107997b2594 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -963,7 +963,7 @@ static int tca_action_flush(struct net *net, struct nlattr *nla,
 		goto out_module_put;
 	}
 
-	err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops);
+	err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops, extack);
 	if (err <= 0) {
 		nla_nest_cancel(skb, nest);
 		goto out_module_put;
@@ -1255,7 +1255,7 @@ static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
 	if (nest == NULL)
 		goto out_module_put;
 
-	ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o);
+	ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o, NULL);
 	if (ret < 0)
 		goto out_module_put;
 
diff --git a/net/sched/act_bpf.c b/net/sched/act_bpf.c
index d9654b8633479..7e01e2c710c4a 100644
--- a/net/sched/act_bpf.c
+++ b/net/sched/act_bpf.c
@@ -367,7 +367,8 @@ static void tcf_bpf_cleanup(struct tc_action *act)
 
 static int tcf_bpf_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, bpf_net_id);
 
diff --git a/net/sched/act_connmark.c b/net/sched/act_connmark.c
index 0504b7600fb6b..cb722da0bb15f 100644
--- a/net/sched/act_connmark.c
+++ b/net/sched/act_connmark.c
@@ -177,7 +177,8 @@ static inline int tcf_connmark_dump(struct sk_buff *skb, struct tc_action *a,
 
 static int tcf_connmark_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, connmark_net_id);
 
diff --git a/net/sched/act_csum.c b/net/sched/act_csum.c
index bdd17b9ef0342..3e8efadb750fa 100644
--- a/net/sched/act_csum.c
+++ b/net/sched/act_csum.c
@@ -631,7 +631,8 @@ static void tcf_csum_cleanup(struct tc_action *a)
 
 static int tcf_csum_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, csum_net_id);
 
diff --git a/net/sched/act_gact.c b/net/sched/act_gact.c
index e1e69e38f4b00..d96ebe4bb65a4 100644
--- a/net/sched/act_gact.c
+++ b/net/sched/act_gact.c
@@ -201,7 +201,8 @@ static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a,
 
 static int tcf_gact_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, gact_net_id);
 
diff --git a/net/sched/act_ife.c b/net/sched/act_ife.c
index 0b70fb0cc6096..b777e381e0dd7 100644
--- a/net/sched/act_ife.c
+++ b/net/sched/act_ife.c
@@ -824,7 +824,8 @@ static int tcf_ife_act(struct sk_buff *skb, const struct tc_action *a,
 
 static int tcf_ife_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, ife_net_id);
 
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
index f29af79a2d1f9..f33a8cc5dee6a 100644
--- a/net/sched/act_ipt.c
+++ b/net/sched/act_ipt.c
@@ -303,7 +303,8 @@ static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind,
 
 static int tcf_ipt_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, ipt_net_id);
 
@@ -352,7 +353,8 @@ static struct pernet_operations ipt_net_ops = {
 
 static int tcf_xt_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, xt_net_id);
 
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index 9980c6affb5e2..3dcd295ea6a7a 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -265,7 +265,8 @@ static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind,
 
 static int tcf_mirred_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, mirred_net_id);
 
diff --git a/net/sched/act_nat.c b/net/sched/act_nat.c
index 6f6d7667ef9a8..67243cdc05883 100644
--- a/net/sched/act_nat.c
+++ b/net/sched/act_nat.c
@@ -278,7 +278,8 @@ static int tcf_nat_dump(struct sk_buff *skb, struct tc_action *a,
 
 static int tcf_nat_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, nat_net_id);
 
diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c
index 308b2680a6d9a..6d6481f6bffa6 100644
--- a/net/sched/act_pedit.c
+++ b/net/sched/act_pedit.c
@@ -419,7 +419,8 @@ static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
 
 static int tcf_pedit_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, pedit_net_id);
 
diff --git a/net/sched/act_police.c b/net/sched/act_police.c
index 1292f880eab00..ff803414a7362 100644
--- a/net/sched/act_police.c
+++ b/net/sched/act_police.c
@@ -58,7 +58,8 @@ static struct tc_action_ops act_police_ops;
 
 static int tcf_act_police_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, police_net_id);
 
diff --git a/net/sched/act_sample.c b/net/sched/act_sample.c
index 22379b2cfd1a0..7a2b6a33f2397 100644
--- a/net/sched/act_sample.c
+++ b/net/sched/act_sample.c
@@ -202,7 +202,8 @@ static int tcf_sample_dump(struct sk_buff *skb, struct tc_action *a,
 
 static int tcf_sample_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, sample_net_id);
 
diff --git a/net/sched/act_simple.c b/net/sched/act_simple.c
index 3ebf714709774..3f5474d20702a 100644
--- a/net/sched/act_simple.c
+++ b/net/sched/act_simple.c
@@ -170,7 +170,8 @@ static int tcf_simp_dump(struct sk_buff *skb, struct tc_action *a,
 
 static int tcf_simp_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, simp_net_id);
 
diff --git a/net/sched/act_skbedit.c b/net/sched/act_skbedit.c
index ff1970e140168..d99b6f1f51814 100644
--- a/net/sched/act_skbedit.c
+++ b/net/sched/act_skbedit.c
@@ -208,7 +208,8 @@ static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
 
 static int tcf_skbedit_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, skbedit_net_id);
 
diff --git a/net/sched/act_skbmod.c b/net/sched/act_skbmod.c
index 110d7c1f823da..369ea85d0f02b 100644
--- a/net/sched/act_skbmod.c
+++ b/net/sched/act_skbmod.c
@@ -232,7 +232,8 @@ static int tcf_skbmod_dump(struct sk_buff *skb, struct tc_action *a,
 
 static int tcf_skbmod_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, skbmod_net_id);
 
diff --git a/net/sched/act_tunnel_key.c b/net/sched/act_tunnel_key.c
index 65a19928f1a94..bced6fd00d435 100644
--- a/net/sched/act_tunnel_key.c
+++ b/net/sched/act_tunnel_key.c
@@ -291,7 +291,8 @@ static int tunnel_key_dump(struct sk_buff *skb, struct tc_action *a,
 
 static int tunnel_key_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, tunnel_key_net_id);
 
diff --git a/net/sched/act_vlan.c b/net/sched/act_vlan.c
index 03dcbbc5ffd2c..7cf409443d02c 100644
--- a/net/sched/act_vlan.c
+++ b/net/sched/act_vlan.c
@@ -267,7 +267,8 @@ static int tcf_vlan_dump(struct sk_buff *skb, struct tc_action *a,
 
 static int tcf_vlan_walker(struct net *net, 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 tc_action_net *tn = net_generic(net, vlan_net_id);
 

From b36201455aa0749e8708ef97ed9c1c9ece29a113 Mon Sep 17 00:00:00 2001
From: Alexander Aring <aring@mojatatu.com>
Date: Thu, 15 Feb 2018 10:54:59 -0500
Subject: [PATCH 7/8] 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      | 3 ++-
 net/sched/act_api.c        | 6 ++++--
 net/sched/act_bpf.c        | 2 +-
 net/sched/act_connmark.c   | 2 +-
 net/sched/act_csum.c       | 2 +-
 net/sched/act_gact.c       | 2 +-
 net/sched/act_ife.c        | 2 +-
 net/sched/act_ipt.c        | 4 ++--
 net/sched/act_mirred.c     | 2 +-
 net/sched/act_nat.c        | 2 +-
 net/sched/act_pedit.c      | 2 +-
 net/sched/act_police.c     | 2 +-
 net/sched/act_sample.c     | 2 +-
 net/sched/act_simple.c     | 2 +-
 net/sched/act_skbedit.c    | 2 +-
 net/sched/act_skbmod.c     | 2 +-
 net/sched/act_tunnel_key.c | 2 +-
 net/sched/act_vlan.c       | 2 +-
 18 files changed, 23 insertions(+), 20 deletions(-)

diff --git a/include/net/act_api.h b/include/net/act_api.h
index ab35292553774..9c2f22695025e 100644
--- a/include/net/act_api.h
+++ b/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);
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index ab107997b2594..1f65d6ada9ff0 100644
--- a/net/sched/act_api.c
+++ b/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;
 	}
 }
diff --git a/net/sched/act_bpf.c b/net/sched/act_bpf.c
index 7e01e2c710c4a..cb3c5d403c887 100644
--- a/net/sched/act_bpf.c
+++ b/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,
diff --git a/net/sched/act_connmark.c b/net/sched/act_connmark.c
index cb722da0bb15f..e4b880fa51fec 100644
--- a/net/sched/act_connmark.c
+++ b/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,
diff --git a/net/sched/act_csum.c b/net/sched/act_csum.c
index 3e8efadb750fa..d5c2e528d150b 100644
--- a/net/sched/act_csum.c
+++ b/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,
diff --git a/net/sched/act_gact.c b/net/sched/act_gact.c
index d96ebe4bb65a4..f072bcf337604 100644
--- a/net/sched/act_gact.c
+++ b/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,
diff --git a/net/sched/act_ife.c b/net/sched/act_ife.c
index b777e381e0dd7..a5994cf0512bd 100644
--- a/net/sched/act_ife.c
+++ b/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,
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
index f33a8cc5dee6a..9784629090ad7 100644
--- a/net/sched/act_ipt.c
+++ b/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,
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index 3dcd295ea6a7a..05c2ebe92ecab 100644
--- a/net/sched/act_mirred.c
+++ b/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,
diff --git a/net/sched/act_nat.c b/net/sched/act_nat.c
index 67243cdc05883..4b5848b6c2520 100644
--- a/net/sched/act_nat.c
+++ b/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,
diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c
index 6d6481f6bffa6..094303c27c5ea 100644
--- a/net/sched/act_pedit.c
+++ b/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,
diff --git a/net/sched/act_police.c b/net/sched/act_police.c
index ff803414a7362..ff55bd6c7db00 100644
--- a/net/sched/act_police.c
+++ b/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] = {
diff --git a/net/sched/act_sample.c b/net/sched/act_sample.c
index 7a2b6a33f2397..9765145aaf406 100644
--- a/net/sched/act_sample.c
+++ b/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,
diff --git a/net/sched/act_simple.c b/net/sched/act_simple.c
index 3f5474d20702a..8244e221fe4f8 100644
--- a/net/sched/act_simple.c
+++ b/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,
diff --git a/net/sched/act_skbedit.c b/net/sched/act_skbedit.c
index d99b6f1f51814..ddf69fc01bdf8 100644
--- a/net/sched/act_skbedit.c
+++ b/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,
diff --git a/net/sched/act_skbmod.c b/net/sched/act_skbmod.c
index 369ea85d0f02b..a406f191cb846 100644
--- a/net/sched/act_skbmod.c
+++ b/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,
diff --git a/net/sched/act_tunnel_key.c b/net/sched/act_tunnel_key.c
index bced6fd00d435..41ff9d0e5c62f 100644
--- a/net/sched/act_tunnel_key.c
+++ b/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,
diff --git a/net/sched/act_vlan.c b/net/sched/act_vlan.c
index 7cf409443d02c..71411a255f04e 100644
--- a/net/sched/act_vlan.c
+++ b/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,

From 1d4760c75d4f8c7c73f040f0261a09cf1481fdec Mon Sep 17 00:00:00 2001
From: Alexander Aring <aring@mojatatu.com>
Date: Thu, 15 Feb 2018 10:55:00 -0500
Subject: [PATCH 8/8] net: sched: act: mirred: add extack support

This patch adds extack support for TC mirred action.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Alexander Aring <aring@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/sched/act_mirred.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index 05c2ebe92ecab..fd34015331ab8 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -80,13 +80,17 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
 	bool exists = false;
 	int ret;
 
-	if (!nla)
+	if (!nla) {
+		NL_SET_ERR_MSG_MOD(extack, "Mirred requires attributes to be passed");
 		return -EINVAL;
-	ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy, NULL);
+	}
+	ret = nla_parse_nested(tb, TCA_MIRRED_MAX, nla, mirred_policy, extack);
 	if (ret < 0)
 		return ret;
-	if (!tb[TCA_MIRRED_PARMS])
+	if (!tb[TCA_MIRRED_PARMS]) {
+		NL_SET_ERR_MSG_MOD(extack, "Missing required mirred parameters");
 		return -EINVAL;
+	}
 	parm = nla_data(tb[TCA_MIRRED_PARMS]);
 
 	exists = tcf_idr_check(tn, parm->index, a, bind);
@@ -102,6 +106,7 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
 	default:
 		if (exists)
 			tcf_idr_release(*a, bind);
+		NL_SET_ERR_MSG_MOD(extack, "Unknown mirred option");
 		return -EINVAL;
 	}
 	if (parm->ifindex) {
@@ -117,8 +122,10 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
 	}
 
 	if (!exists) {
-		if (!dev)
+		if (!dev) {
+			NL_SET_ERR_MSG_MOD(extack, "Specified device does not exist");
 			return -EINVAL;
+		}
 		ret = tcf_idr_create(tn, parm->index, est, a,
 				     &act_mirred_ops, bind, true);
 		if (ret)