Commit bbcf9105 authored by Eric Dumazet's avatar Eric Dumazet Committed by Jakub Kicinski
Browse files

inet: do not use RTNL in inet_netconf_get_devconf() 



"ip -4 netconf show dev XXXX" no longer acquires RTNL.

Return -ENODEV instead of -EINVAL if no netdev or idev can be found.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarJiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20240227092411.2315725-3-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 0598f8f3

net/ipv4/devinet.c

+15 −12
Original line number Diff line number Diff line
@@ -2206,20 +2206,19 @@ static int inet_netconf_get_devconf(struct sk_buff *in_skb, 
{

	struct net *net = sock_net(in_skb->sk);

	struct nlattr *tb[NETCONFA_MAX + 1];

	const struct ipv4_devconf *devconf;

	struct in_device *in_dev = NULL;

	struct net_device *dev = NULL;

	struct sk_buff *skb;

	struct ipv4_devconf *devconf;

	struct in_device *in_dev;

	struct net_device *dev;

	int ifindex;

	int err;



	err = inet_netconf_valid_get_req(in_skb, nlh, tb, extack);

	if (err)

		goto errout;

		return err;



	err = -EINVAL;

	if (!tb[NETCONFA_IFINDEX])

		goto errout;

		return -EINVAL;



	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);

	switch (ifindex) {
@@ -2230,10 +2229,10 @@ static int inet_netconf_get_devconf(struct sk_buff *in_skb, 
		devconf = net->ipv4.devconf_dflt;

		break;

	default:

		dev = __dev_get_by_index(net, ifindex);

		if (!dev)

			goto errout;

		in_dev = __in_dev_get_rtnl(dev);

		err = -ENODEV;

		dev = dev_get_by_index(net, ifindex);

		if (dev)

			in_dev = in_dev_get(dev);

		if (!in_dev)

			goto errout;

		devconf = &in_dev->cnf;
@@ -2257,6 +2256,9 @@ static int inet_netconf_get_devconf(struct sk_buff *in_skb, 
	}

	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);

errout:

	if (in_dev)

		in_dev_put(in_dev);

	dev_put(dev);

	return err;

}
@@ -2826,5 +2828,6 @@ void __init devinet_init(void) 
	rtnl_register(PF_INET, RTM_DELADDR, inet_rtm_deladdr, NULL, 0);

	rtnl_register(PF_INET, RTM_GETADDR, NULL, inet_dump_ifaddr, 0);

	rtnl_register(PF_INET, RTM_GETNETCONF, inet_netconf_get_devconf,

		      inet_netconf_dump_devconf, 0);

		      inet_netconf_dump_devconf,

		      RTNL_FLAG_DOIT_UNLOCKED);

}