Merge branch 'nla_nest_start'

Michal Kubecek says:

====================
make nla_nest_start() add NLA_F_NESTED flag

One of the comments in recent review of the ethtool netlink series pointed
out that proposed ethnl_nest_start() helper which adds NLA_F_NESTED to
second argument of nla_nest_start() is not really specific to ethtool
netlink code. That is hard to argue with as closer inspection revealed that
exactly the same helper already exists in ipset code (except it's a macro
rather than an inline function).

Another observation was that even if NLA_F_NESTED flag was introduced in
2007, only few netlink based interfaces set it in kernel generated messages
and even many recently added APIs omit it. That is unfortunate as without
the flag, message parsers not familiar with attribute semantics cannot
recognize nested attributes and do not see message structure; this affects
e.g. wireshark dissector or mnl_nlmsg_fprintf() from libmnl.

This is why I'm suggesting to rename existing nla_nest_start() to different
name (nla_nest_start_noflag) and reintroduce nla_nest_start() as a wrapper
adding NLA_F_NESTED flag. This is implemented in first patch which is
mostly generated by spatch. Second patch drops ipset helper macros which
lose their purpose. Third patch cleans up minor coding style issues found
by checkpatch.pl in first patch.

We could leave nla_nest_start() untouched and simply add a wrapper adding
NLA_F_NESTED but that would probably preserve the state when even most new
code doesn't set the flag.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

101 files changed, 492 insertions, 444 deletions

diff --git a/net/8021q/vlan_netlink.c b/net/8021q/vlan_netlink.c
index a624dccf68fd..ab4921e7797b 100644
--- a/net/8021q/vlan_netlink.c
+++ b/net/8021q/vlan_netlink.c
@@ -227,7 +227,7 @@ static int vlan_fill_info(struct sk_buff *skb, const struct net_device *dev)
 			goto nla_put_failure;
 	}
 	if (vlan->nr_ingress_mappings) {
-		nest = nla_nest_start(skb, IFLA_VLAN_INGRESS_QOS);
+		nest = nla_nest_start_noflag(skb, IFLA_VLAN_INGRESS_QOS);
 		if (nest == NULL)
 			goto nla_put_failure;
 
@@ -245,7 +245,7 @@ static int vlan_fill_info(struct sk_buff *skb, const struct net_device *dev)
 	}
 
 	if (vlan->nr_egress_mappings) {
-		nest = nla_nest_start(skb, IFLA_VLAN_EGRESS_QOS);
+		nest = nla_nest_start_noflag(skb, IFLA_VLAN_EGRESS_QOS);
 		if (nest == NULL)
 			goto nla_put_failure;
 
diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index f69c8d91dc81..3619c1a12a77 100644
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -26,14 +26,14 @@ static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
 	if (!br->multicast_router || hlist_empty(&br->router_list))
 		return 0;
 
-	nest = nla_nest_start(skb, MDBA_ROUTER);
+	nest = nla_nest_start_noflag(skb, MDBA_ROUTER);
 	if (nest == NULL)
 		return -EMSGSIZE;
 
 	hlist_for_each_entry_rcu(p, &br->router_list, rlist) {
 		if (!p)
 			continue;
-		port_nest = nla_nest_start(skb, MDBA_ROUTER_PORT);
+		port_nest = nla_nest_start_noflag(skb, MDBA_ROUTER_PORT);
 		if (!port_nest)
 			goto fail;
 		if (nla_put_nohdr(skb, sizeof(u32), &p->dev->ifindex) ||
@@ -86,7 +86,7 @@ static int br_mdb_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
 	if (!br_opt_get(br, BROPT_MULTICAST_ENABLED))
 		return 0;
 
-	nest = nla_nest_start(skb, MDBA_MDB);
+	nest = nla_nest_start_noflag(skb, MDBA_MDB);
 	if (nest == NULL)
 		return -EMSGSIZE;
 
@@ -98,7 +98,7 @@ static int br_mdb_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
 		if (idx < s_idx)
 			goto skip;
 
-		nest2 = nla_nest_start(skb, MDBA_MDB_ENTRY);
+		nest2 = nla_nest_start_noflag(skb, MDBA_MDB_ENTRY);
 		if (!nest2) {
 			err = -EMSGSIZE;
 			break;
@@ -124,7 +124,8 @@ static int br_mdb_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
 				e.addr.u.ip6 = p->addr.u.ip6;
 #endif
 			e.addr.proto = p->addr.proto;
-			nest_ent = nla_nest_start(skb, MDBA_MDB_ENTRY_INFO);
+			nest_ent = nla_nest_start_noflag(skb,
+							 MDBA_MDB_ENTRY_INFO);
 			if (!nest_ent) {
 				nla_nest_cancel(skb, nest2);
 				err = -EMSGSIZE;
@@ -248,10 +249,10 @@ static int nlmsg_populate_mdb_fill(struct sk_buff *skb,
 	memset(bpm, 0, sizeof(*bpm));
 	bpm->family  = AF_BRIDGE;
 	bpm->ifindex = dev->ifindex;
-	nest = nla_nest_start(skb, MDBA_MDB);
+	nest = nla_nest_start_noflag(skb, MDBA_MDB);
 	if (nest == NULL)
 		goto cancel;
-	nest2 = nla_nest_start(skb, MDBA_MDB_ENTRY);
+	nest2 = nla_nest_start_noflag(skb, MDBA_MDB_ENTRY);
 	if (nest2 == NULL)
 		goto end;
 
@@ -444,7 +445,7 @@ static int nlmsg_populate_rtr_fill(struct sk_buff *skb,
 	memset(bpm, 0, sizeof(*bpm));
 	bpm->family = AF_BRIDGE;
 	bpm->ifindex = dev->ifindex;
-	nest = nla_nest_start(skb, MDBA_ROUTER);
+	nest = nla_nest_start_noflag(skb, MDBA_ROUTER);
 	if (!nest)
 		goto cancel;
 
diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index 8dfcc2d285d8..348ddb6d09bb 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -413,9 +413,9 @@ static int br_fill_ifinfo(struct sk_buff *skb,
 		goto nla_put_failure;
 
 	if (event == RTM_NEWLINK && port) {
-		struct nlattr *nest
-			= nla_nest_start(skb, IFLA_PROTINFO | NLA_F_NESTED);
+		struct nlattr *nest;
 
+		nest = nla_nest_start(skb, IFLA_PROTINFO);
 		if (nest == NULL || br_port_fill_attrs(skb, port) < 0)
 			goto nla_put_failure;
 		nla_nest_end(skb, nest);
@@ -439,7 +439,7 @@ static int br_fill_ifinfo(struct sk_buff *skb,
 			rcu_read_unlock();
 			goto done;
 		}
-		af = nla_nest_start(skb, IFLA_AF_SPEC);
+		af = nla_nest_start_noflag(skb, IFLA_AF_SPEC);
 		if (!af) {
 			rcu_read_unlock();
 			goto nla_put_failure;
@@ -1569,7 +1569,7 @@ static int br_fill_linkxstats(struct sk_buff *skb,
 		return -EINVAL;
 	}
 
-	nest = nla_nest_start(skb, LINK_XSTATS_TYPE_BRIDGE);
+	nest = nla_nest_start_noflag(skb, LINK_XSTATS_TYPE_BRIDGE);
 	if (!nest)
 		return -EMSGSIZE;
 
diff --git a/net/bridge/br_netlink_tunnel.c b/net/bridge/br_netlink_tunnel.c
index da8cb99fd259..787e140dc4b5 100644
--- a/net/bridge/br_netlink_tunnel.c
+++ b/net/bridge/br_netlink_tunnel.c
@@ -97,7 +97,7 @@ static int br_fill_vlan_tinfo(struct sk_buff *skb, u16 vid,
 	__be32 tid = tunnel_id_to_key32(tunnel_id);
 	struct nlattr *tmap;
 
-	tmap = nla_nest_start(skb, IFLA_BRIDGE_VLAN_TUNNEL_INFO);
+	tmap = nla_nest_start_noflag(skb, IFLA_BRIDGE_VLAN_TUNNEL_INFO);
 	if (!tmap)
 		return -EMSGSIZE;
 	if (nla_put_u32(skb, IFLA_BRIDGE_VLAN_TUNNEL_ID,
diff --git a/net/core/devlink.c b/net/core/devlink.c
index 7b91605e75d6..b94f326f5f06 100644
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -1671,7 +1671,7 @@ int devlink_dpipe_match_put(struct sk_buff *skb,
 	struct devlink_dpipe_field *field = &header->fields[match->field_id];
 	struct nlattr *match_attr;
 
-	match_attr = nla_nest_start(skb, DEVLINK_ATTR_DPIPE_MATCH);
+	match_attr = nla_nest_start_noflag(skb, DEVLINK_ATTR_DPIPE_MATCH);
 	if (!match_attr)
 		return -EMSGSIZE;
 
@@ -1696,7 +1696,8 @@ static int devlink_dpipe_matches_put(struct devlink_dpipe_table *table,
 {
 	struct nlattr *matches_attr;
 
-	matches_attr = nla_nest_start(skb, DEVLINK_ATTR_DPIPE_TABLE_MATCHES);
+	matches_attr = nla_nest_start_noflag(skb,
+					     DEVLINK_ATTR_DPIPE_TABLE_MATCHES);
 	if (!matches_attr)
 		return -EMSGSIZE;
 
@@ -1718,7 +1719,7 @@ int devlink_dpipe_action_put(struct sk_buff *skb,
 	struct devlink_dpipe_field *field = &header->fields[action->field_id];
 	struct nlattr *action_attr;
 
-	action_attr = nla_nest_start(skb, DEVLINK_ATTR_DPIPE_ACTION);
+	action_attr = nla_nest_start_noflag(skb, DEVLINK_ATTR_DPIPE_ACTION);
 	if (!action_attr)
 		return -EMSGSIZE;
 
@@ -1743,7 +1744,8 @@ static int devlink_dpipe_actions_put(struct devlink_dpipe_table *table,
 {
 	struct nlattr *actions_attr;
 
-	actions_attr = nla_nest_start(skb, DEVLINK_ATTR_DPIPE_TABLE_ACTIONS);
+	actions_attr = nla_nest_start_noflag(skb,
+					     DEVLINK_ATTR_DPIPE_TABLE_ACTIONS);
 	if (!actions_attr)
 		return -EMSGSIZE;
 
@@ -1765,7 +1767,7 @@ static int devlink_dpipe_table_put(struct sk_buff *skb,
 	u64 table_size;
 
 	table_size = table->table_ops->size_get(table->priv);
-	table_attr = nla_nest_start(skb, DEVLINK_ATTR_DPIPE_TABLE);
+	table_attr = nla_nest_start_noflag(skb, DEVLINK_ATTR_DPIPE_TABLE);
 	if (!table_attr)
 		return -EMSGSIZE;
 
@@ -1845,7 +1847,7 @@ start_again:
 
 	if (devlink_nl_put_handle(skb, devlink))
 		goto nla_put_failure;
-	tables_attr = nla_nest_start(skb, DEVLINK_ATTR_DPIPE_TABLES);
+	tables_attr = nla_nest_start_noflag(skb, DEVLINK_ATTR_DPIPE_TABLES);
 	if (!tables_attr)
 		goto nla_put_failure;
 
@@ -1946,8 +1948,8 @@ static int devlink_dpipe_action_values_put(struct sk_buff *skb,
 	int err;
 
 	for (i = 0; i < values_count; i++) {
-		action_attr = nla_nest_start(skb,
-					     DEVLINK_ATTR_DPIPE_ACTION_VALUE);
+		action_attr = nla_nest_start_noflag(skb,
+						    DEVLINK_ATTR_DPIPE_ACTION_VALUE);
 		if (!action_attr)
 			return -EMSGSIZE;
 		err = devlink_dpipe_action_value_put(skb, &values[i]);
@@ -1983,8 +1985,8 @@ static int devlink_dpipe_match_values_put(struct sk_buff *skb,
 	int err;
 
 	for (i = 0; i < values_count; i++) {
-		match_attr = nla_nest_start(skb,
-					    DEVLINK_ATTR_DPIPE_MATCH_VALUE);
+		match_attr = nla_nest_start_noflag(skb,
+						   DEVLINK_ATTR_DPIPE_MATCH_VALUE);
 		if (!match_attr)
 			return -EMSGSIZE;
 		err = devlink_dpipe_match_value_put(skb, &values[i]);
@@ -2005,7 +2007,7 @@ static int devlink_dpipe_entry_put(struct sk_buff *skb,
 	struct nlattr *entry_attr, *matches_attr, *actions_attr;
 	int err;
 
-	entry_attr = nla_nest_start(skb, DEVLINK_ATTR_DPIPE_ENTRY);
+	entry_attr = nla_nest_start_noflag(skb, DEVLINK_ATTR_DPIPE_ENTRY);
 	if (!entry_attr)
 		return  -EMSGSIZE;
 
@@ -2017,8 +2019,8 @@ static int devlink_dpipe_entry_put(struct sk_buff *skb,
 				      entry->counter, DEVLINK_ATTR_PAD))
 			goto nla_put_failure;
 
-	matches_attr = nla_nest_start(skb,
-				      DEVLINK_ATTR_DPIPE_ENTRY_MATCH_VALUES);
+	matches_attr = nla_nest_start_noflag(skb,
+					     DEVLINK_ATTR_DPIPE_ENTRY_MATCH_VALUES);
 	if (!matches_attr)
 		goto nla_put_failure;
 
@@ -2030,8 +2032,8 @@ static int devlink_dpipe_entry_put(struct sk_buff *skb,
 	}
 	nla_nest_end(skb, matches_attr);
 
-	actions_attr = nla_nest_start(skb,
-				      DEVLINK_ATTR_DPIPE_ENTRY_ACTION_VALUES);
+	actions_attr = nla_nest_start_noflag(skb,