Commit 89da780a authored by Xin Long's avatar Xin Long Committed by Jakub Kicinski
Browse files

rtnetlink: move validate_linkmsg out of do_setlink 



This patch moves validate_linkmsg() out of do_setlink() to its callers
and deletes the early validate_linkmsg() call in __rtnl_newlink(), so
that it will not call validate_linkmsg() twice in either of the paths:

  - __rtnl_newlink() -> do_setlink()
  - __rtnl_newlink() -> rtnl_newlink_create() -> rtnl_create_link()

Additionally, as validate_linkmsg() is now only called with a real
dev, we can remove the NULL check for dev in validate_linkmsg().

Note that we moved validate_linkmsg() check to the places where it has
not done any changes to the dev, as Jakub suggested.

Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Reviewed-by: default avatarSimon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/r/cf2ef061e08251faf9e8be25ff0d61150c030475.1686585334.git.lucien.xin@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent fa0e21fa

net/core/rtnetlink.c

+42 −41
Original line number Diff line number Diff line
@@ -2383,7 +2383,6 @@ static int rtnl_set_vf_rate(struct net_device *dev, int vf, int min_tx_rate, 
static int validate_linkmsg(struct net_device *dev, struct nlattr *tb[],

			    struct netlink_ext_ack *extack)

{

	if (dev) {

	if (tb[IFLA_ADDRESS] &&

	    nla_len(tb[IFLA_ADDRESS]) < dev->addr_len)

		return -EINVAL;
@@ -2422,7 +2421,6 @@ static int validate_linkmsg(struct net_device *dev, struct nlattr *tb[], 
		NL_SET_ERR_MSG(extack, "too big gro_ipv4_max_size");

		return -EINVAL;

	}

	}



	if (tb[IFLA_AF_SPEC]) {

		struct nlattr *af;
@@ -2742,10 +2740,6 @@ static int do_setlink(const struct sk_buff *skb, 
	char ifname[IFNAMSIZ];

	int err;



	err = validate_linkmsg(dev, tb, extack);

	if (err < 0)

		return err;



	if (tb[IFLA_IFNAME])

		nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);

	else
@@ -3162,6 +3156,10 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, 
		goto errout;

	}



	err = validate_linkmsg(dev, tb, extack);

	if (err < 0)

		goto errout;



	err = do_setlink(skb, dev, ifm, extack, tb, 0);

errout:

	return err;
@@ -3405,6 +3403,9 @@ static int rtnl_group_changelink(const struct sk_buff *skb, 


	for_each_netdev_safe(net, dev, aux) {

		if (dev->group == group) {

			err = validate_linkmsg(dev, tb, extack);

			if (err < 0)

				return err;

			err = do_setlink(skb, dev, ifm, extack, tb, 0);

			if (err < 0)

				return err;
@@ -3562,10 +3563,6 @@ static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, 
			m_ops = master_dev->rtnl_link_ops;

	}



	err = validate_linkmsg(dev, tb, extack);

	if (err < 0)

		return err;



	if (tb[IFLA_LINKINFO]) {

		err = nla_parse_nested_deprecated(linkinfo, IFLA_INFO_MAX,

						  tb[IFLA_LINKINFO],
@@ -3629,6 +3626,10 @@ static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, 
		if (nlh->nlmsg_flags & NLM_F_REPLACE)

			return -EOPNOTSUPP;



		err = validate_linkmsg(dev, tb, extack);

		if (err < 0)

			return err;



		if (linkinfo[IFLA_INFO_DATA]) {

			if (!ops || ops != dev->rtnl_link_ops ||

			    !ops->changelink)