From: Jiri Pirko <jiri@mellanox.com>
Date: Sat, 5 Oct 2019 20:04:36 +0200
Subject: net: genetlink: parse attrs and store in contect info struct during
 dumpit
Patch-mainline: v5.5-rc1
Git-commit: bf813b0afeae2f012f0e527a526c1b78ca21ad82
References: bsc#1154353

Extend the dumpit info struct for attrs. Instead of existing attribute
validation do parse them and save in the info struct. Caller can benefit
from this and does not have to do parse itself. In order to properly
free attrs, genl_family pointer needs to be added to dumpit info struct
as well.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 include/net/genetlink.h |    4 ++++
 net/netlink/genetlink.c |   41 +++++++++++++++++++++++------------------
 2 files changed, 27 insertions(+), 18 deletions(-)

--- a/include/net/genetlink.h
+++ b/include/net/genetlink.h
@@ -129,10 +129,14 @@ enum genl_validate_flags {
 
 /**
  * struct genl_info - info that is available during dumpit op call
+ * @family: generic netlink family - for internal genl code usage
  * @ops: generic netlink ops - for internal genl code usage
+ * @attrs: netlink attributes
  */
 struct genl_dumpit_info {
+	const struct genl_family *family;
 	const struct genl_ops *ops;
+	struct nlattr **attrs;
 };
 
 static inline const struct genl_dumpit_info *
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -542,6 +542,7 @@ static int genl_lock_done(struct netlink
 		rc = ops->done(cb);
 		genl_unlock();
 	}
+	genl_family_rcv_msg_attrs_free(info->family, info->attrs);
 	genl_dumpit_info_free(info);
 	return rc;
 }
@@ -554,6 +555,7 @@ static int genl_parallel_done(struct net
 
 	if (ops->done)
 		rc = ops->done(cb);
+	genl_family_rcv_msg_attrs_free(info->family, info->attrs);
 	genl_dumpit_info_free(info);
 	return rc;
 }
@@ -566,35 +568,38 @@ static int genl_family_rcv_msg_dumpit(co
 				      int hdrlen, struct net *net)
 {
 	struct genl_dumpit_info *info;
+	struct nlattr **attrs = NULL;
 	int err;
 
 	if (!ops->dumpit)
 		return -EOPNOTSUPP;
 
-	if (!(ops->validate & GENL_DONT_VALIDATE_DUMP)) {
-		if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
-			return -EINVAL;
-
-		if (family->maxattr) {
-			unsigned int validate = NL_VALIDATE_STRICT;
-
-			if (ops->validate & GENL_DONT_VALIDATE_DUMP_STRICT)
-				validate = NL_VALIDATE_LIBERAL;
-			err = __nla_validate(nlmsg_attrdata(nlh, hdrlen),
-					     nlmsg_attrlen(nlh, hdrlen),
-					     family->maxattr, family->policy,
-					     validate, extack);
-			if (err)
-				return err;
-		}
-	}
+	if (ops->validate & GENL_DONT_VALIDATE_DUMP)
+		goto no_attrs;
+
+	if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
+		return -EINVAL;
+
+	if (!family->maxattr)
+		goto no_attrs;
 
+	attrs = genl_family_rcv_msg_attrs_parse(family, nlh, extack,
+						ops, hdrlen,
+						GENL_DONT_VALIDATE_DUMP_STRICT);
+	if (IS_ERR(attrs))
+		return PTR_ERR(attrs);
+
+no_attrs:
 	/* Allocate dumpit info. It is going to be freed by done() callback. */
 	info = genl_dumpit_info_alloc();
-	if (!info)
+	if (!info) {
+		genl_family_rcv_msg_attrs_free(family, attrs);
 		return -ENOMEM;
+	}
 
+	info->family = family;
 	info->ops = ops;
+	info->attrs = attrs;
 
 	if (!family->parallel_ops) {
 		struct netlink_dump_control c = {