From: Jiri Pirko <jiri@mellanox.com>
Date: Sat, 5 Oct 2019 20:04:42 +0200
Subject: devlink: have genetlink code to parse the attrs during dumpit
Patch-mainline: v5.5-rc1
Git-commit: ee85da535fe30e02908d30ec6b8960c4a991cb2d
References: bsc#1154353

Benefit from the fact that the generic netlink code can parse the attrs
for dumpit op and avoid need to parse it in the op callback.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 net/core/devlink.c |   38 ++++++--------------------------------
 1 file changed, 6 insertions(+), 32 deletions(-)

--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -3943,29 +3943,19 @@ static int devlink_nl_region_read_snapsh
 static int devlink_nl_cmd_region_read_dumpit(struct sk_buff *skb,
 					     struct netlink_callback *cb)
 {
+	const struct genl_dumpit_info *info = genl_dumpit_info(cb);
 	u64 ret_offset, start_offset, end_offset = 0;
+	struct nlattr **attrs = info->attrs;
 	struct devlink_region *region;
 	struct nlattr *chunks_attr;
 	const char *region_name;
 	struct devlink *devlink;
-	struct nlattr **attrs;
 	bool dump = true;
 	void *hdr;
 	int err;
 
 	start_offset = *((u64 *)&cb->args[0]);
 
-	attrs = kmalloc_array(DEVLINK_ATTR_MAX + 1, sizeof(*attrs), GFP_KERNEL);
-	if (!attrs)
-		return -ENOMEM;
-
-	err = nlmsg_parse_deprecated(cb->nlh,
-				     GENL_HDRLEN + devlink_nl_family.hdrsize,
-				     attrs, DEVLINK_ATTR_MAX,
-				     devlink_nl_family.policy, cb->extack);
-	if (err)
-		goto out_free;
-
 	mutex_lock(&devlink_mutex);
 	devlink = devlink_get_from_attrs(sock_net(cb->skb->sk), attrs);
 	if (IS_ERR(devlink)) {
@@ -4042,7 +4032,6 @@ static int devlink_nl_cmd_region_read_du
 	genlmsg_end(skb, hdr);
 	mutex_unlock(&devlink->lock);
 	mutex_unlock(&devlink_mutex);
-	kfree(attrs);
 
 	return skb->len;
 
@@ -4052,8 +4041,6 @@ out_unlock:
 	mutex_unlock(&devlink->lock);
 out_dev:
 	mutex_unlock(&devlink_mutex);
-out_free:
-	kfree(attrs);
 	return err;
 }
 
@@ -4997,21 +4984,10 @@ devlink_health_reporter_get_from_info(st
 static struct devlink_health_reporter *
 devlink_health_reporter_get_from_cb(struct netlink_callback *cb)
 {
+	const struct genl_dumpit_info *info = genl_dumpit_info(cb);
 	struct devlink_health_reporter *reporter;
+	struct nlattr **attrs = info->attrs;
 	struct devlink *devlink;
-	struct nlattr **attrs;
-	int err;
-
-	attrs = kmalloc_array(DEVLINK_ATTR_MAX + 1, sizeof(*attrs), GFP_KERNEL);
-	if (!attrs)
-		return NULL;
-
-	err = nlmsg_parse_deprecated(cb->nlh,
-				     GENL_HDRLEN + devlink_nl_family.hdrsize,
-				     attrs, DEVLINK_ATTR_MAX,
-				     devlink_nl_family.policy, cb->extack);
-	if (err)
-		goto free;
 
 	mutex_lock(&devlink_mutex);
 	devlink = devlink_get_from_attrs(sock_net(cb->skb->sk), attrs);
@@ -5020,12 +4996,9 @@ devlink_health_reporter_get_from_cb(stru
 
 	reporter = devlink_health_reporter_get_from_attrs(devlink, attrs);
 	mutex_unlock(&devlink_mutex);
-	kfree(attrs);
 	return reporter;
 unlock:
 	mutex_unlock(&devlink_mutex);
-free:
-	kfree(attrs);
 	return NULL;
 }
 
@@ -6160,7 +6133,8 @@ static const struct genl_ops devlink_nl_
 	},
 	{
 		.cmd = DEVLINK_CMD_REGION_READ,
-		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
+		.validate = GENL_DONT_VALIDATE_STRICT |
+			    GENL_DONT_VALIDATE_DUMP_STRICT,
 		.dumpit = devlink_nl_cmd_region_read_dumpit,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK,