From addd383f5a0ba9bf8336be3cc8b7a2916c08a77a Mon Sep 17 00:00:00 2001 From: David Ahern Date: Sun, 7 Oct 2018 20:16:41 -0700 Subject: net: Update netconf dump handlers for strict data checking Update inet_netconf_dump_devconf, inet6_netconf_dump_devconf, and mpls_netconf_dump_devconf for strict data checking. If the flag is set, the dump request is expected to have an netconfmsg struct as the header. The struct only has the family member and no attributes can be appended. Signed-off-by: David Ahern Acked-by: Christian Brauner Signed-off-by: David S. Miller --- net/ipv4/devinet.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) (limited to 'net/ipv4/devinet.c') diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 6f2bbd04e950..d122ebbe5980 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -2086,6 +2086,7 @@ errout: static int inet_netconf_dump_devconf(struct sk_buff *skb, struct netlink_callback *cb) { + const struct nlmsghdr *nlh = cb->nlh; struct net *net = sock_net(skb->sk); int h, s_h; int idx, s_idx; @@ -2093,6 +2094,21 @@ static int inet_netconf_dump_devconf(struct sk_buff *skb, struct in_device *in_dev; struct hlist_head *head; + if (cb->strict_check) { + struct netlink_ext_ack *extack = cb->extack; + struct netconfmsg *ncm; + + if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) { + NL_SET_ERR_MSG(extack, "ipv4: Invalid header for netconf dump request"); + return -EINVAL; + } + + if (nlmsg_attrlen(nlh, sizeof(*ncm))) { + NL_SET_ERR_MSG(extack, "ipv4: Invalid data after header in netconf dump request"); + return -EINVAL; + } + } + s_h = cb->args[0]; s_idx = idx = cb->args[1]; @@ -2112,7 +2128,7 @@ static int inet_netconf_dump_devconf(struct sk_buff *skb, if (inet_netconf_fill_devconf(skb, dev->ifindex, &in_dev->cnf, NETLINK_CB(cb->skb).portid, - cb->nlh->nlmsg_seq, + nlh->nlmsg_seq, RTM_NEWNETCONF, NLM_F_MULTI, NETCONFA_ALL) < 0) { @@ -2129,7 +2145,7 @@ cont: if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL, net->ipv4.devconf_all, NETLINK_CB(cb->skb).portid, - cb->nlh->nlmsg_seq, + nlh->nlmsg_seq, RTM_NEWNETCONF, NLM_F_MULTI, NETCONFA_ALL) < 0) goto done; @@ -2140,7 +2156,7 @@ cont: if (inet_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT, net->ipv4.devconf_dflt, NETLINK_CB(cb->skb).portid, - cb->nlh->nlmsg_seq, + nlh->nlmsg_seq, RTM_NEWNETCONF, NLM_F_MULTI, NETCONFA_ALL) < 0) goto done; -- cgit v1.2.3-59-g8ed1b