Commit b0ad3c17 authored May 31, 2023 by Xin Long Committed by Jakub Kicinski Jun 01, 2023

rtnetlink: call validate_linkmsg in rtnl_create_link



validate_linkmsg() was introduced by commit 1840bb13 ("[RTNL]:
Validate hardware and broadcast address attribute for RTM_NEWLINK")
to validate tb[IFLA_ADDRESS/BROADCAST] for existing links. The same
check should also be done for newly created links.

This patch adds validate_linkmsg() call in rtnl_create_link(), to
avoid the invalid address set when creating some devices like:

  # ip link add dummy0 type dummy
  # ip link add link dummy0 name mac0 address 01:02 type macsec

Fixes: 0e06877c ("[RTNETLINK]: rtnl_link: allow specifying initial device address")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

parent abaf8d51

net/core/rtnetlink.c

+7 −1

Original line number	Diff line number	Diff line
		@@ -3285,6 +3285,7 @@ struct net_device rtnl_create_link(struct net net, const char *ifname,
		struct net_device *dev;
		unsigned int num_tx_queues = 1;
		unsigned int num_rx_queues = 1;
		int err;

		if (tb[IFLA_NUM_TX_QUEUES])
		num_tx_queues = nla_get_u32(tb[IFLA_NUM_TX_QUEUES]);
		@@ -3320,13 +3321,18 @@ struct net_device rtnl_create_link(struct net net, const char *ifname,
		if (!dev)
		return ERR_PTR(-ENOMEM);

		err = validate_linkmsg(dev, tb, extack);
		if (err < 0) {
		free_netdev(dev);
		return ERR_PTR(err);
		}

		dev_net_set(dev, net);
		dev->rtnl_link_ops = ops;
		dev->rtnl_link_state = RTNL_LINK_INITIALIZING;

		if (tb[IFLA_MTU]) {
		u32 mtu = nla_get_u32(tb[IFLA_MTU]);
		int err;

		err = dev_validate_mtu(dev, mtu, extack);
		if (err) {