From 38d51810c4cadd672cb819bbb913e54fddfa1508 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Fri, 18 Jan 2019 10:46:22 -0800 Subject: [PATCH] net: ipv6: 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: Jakub Kicinski Signed-off-by: David S. Miller --- net/ipv6/addrconf.c | 41 ++++++++++++++++++++++++++++++++++++++--- 1 file changed, 38 insertions(+), 3 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 339a82cfe5f2..57198b3c86da 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -597,6 +597,43 @@ static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = { [NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN] = { .len = sizeof(int) }, }; +static int inet6_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_MOD(extack, "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_ipv6_policy, extack); + + err = nlmsg_parse_strict(nlh, sizeof(struct netconfmsg), tb, + NETCONFA_MAX, devconf_ipv6_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_MOD(extack, "Unsupported attribute in netconf get request"); + return -EINVAL; + } + } + + return 0; +} + static int inet6_netconf_get_devconf(struct sk_buff *in_skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) @@ -605,14 +642,12 @@ static int inet6_netconf_get_devconf(struct sk_buff *in_skb, struct nlattr *tb[NETCONFA_MAX+1]; struct inet6_dev *in6_dev = NULL; struct net_device *dev = NULL; - struct netconfmsg *ncm; struct sk_buff *skb; struct ipv6_devconf *devconf; int ifindex; int err; - err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX, - devconf_ipv6_policy, extack); + err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack); if (err < 0) return err; -- 2.30.2