Commit eede370d authored by Jakub Kicinski's avatar Jakub Kicinski Committed by David S. Miller
Browse files

net: ipv4: netconf: perform strict checks also for doit handlers 



Make RTM_GETNETCONF's doit handler use strict checks when
NETLINK_F_STRICT_CHK is set.

Signed-off-by: default avatarJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 4d165f61

net/ipv4/devinet.c

+39 −4
Original line number Diff line number Diff line
@@ -2063,13 +2063,49 @@ static const struct nla_policy devconf_ipv4_policy[NETCONFA_MAX+1] = { 
	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },

};



static int inet_netconf_valid_get_req(struct sk_buff *skb,

				      const struct nlmsghdr *nlh,

				      struct nlattr **tb,

				      struct netlink_ext_ack *extack)

{

	int i, err;



	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {

		NL_SET_ERR_MSG(extack, "ipv4: Invalid header for netconf get request");

		return -EINVAL;

	}



	if (!netlink_strict_get_check(skb))

		return nlmsg_parse(nlh, sizeof(struct netconfmsg), tb,

				   NETCONFA_MAX, devconf_ipv4_policy, extack);



	err = nlmsg_parse_strict(nlh, sizeof(struct netconfmsg), tb,

				 NETCONFA_MAX, devconf_ipv4_policy, extack);

	if (err)

		return err;



	for (i = 0; i <= NETCONFA_MAX; i++) {

		if (!tb[i])

			continue;



		switch (i) {

		case NETCONFA_IFINDEX:

			break;

		default:

			NL_SET_ERR_MSG(extack, "ipv4: Unsupported attribute in netconf get request");

			return -EINVAL;

		}

	}



	return 0;

}



static int inet_netconf_get_devconf(struct sk_buff *in_skb,

				    struct nlmsghdr *nlh,

				    struct netlink_ext_ack *extack)

{

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

	struct nlattr *tb[NETCONFA_MAX+1];

	struct netconfmsg *ncm;

	struct sk_buff *skb;

	struct ipv4_devconf *devconf;

	struct in_device *in_dev;
@@ -2077,9 +2113,8 @@ static int inet_netconf_get_devconf(struct sk_buff *in_skb, 
	int ifindex;

	int err;



	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,

			  devconf_ipv4_policy, extack);

	if (err < 0)

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

	if (err)

		goto errout;



	err = -EINVAL;