netfilter: conntrack: validate cta_ip via parsing

In current ctnetlink_parse_tuple_ip() function, nested parsing and
validation is splitting as two parts,  which could be cleanup to a
simplified form. As the nla_parse_nested_deprecated function
supports validation in the fly. These two finially reach same place
__nla_validate_parse with same validate flag.

nla_parse_nested_deprecated
  __nla_parse(.., NL_VALIDATE_LIBERAL, ..)
    __nla_validate_parse

nla_validate_nested_deprecated
  __nla_validate_nested(.., NL_VALIDATE_LIBERAL, ..)
    __nla_validate
      __nla_validate_parse

This commit removes the call to nla_validate_nested_deprecated and pass
cta_ip_nla_policy when do parsing.

Signed-off-by: Lin Ma <linma@zju.edu.cn>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Florian Westphal <fw@strlen.de>

diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 69c8c8c..334db22 100644 (file)
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -1321,15 +1321,11 @@ static int ctnetlink_parse_tuple_ip(struct nlattr *attr,
        struct nlattr *tb[CTA_IP_MAX+1];
        int ret = 0;
 
-       ret = nla_parse_nested_deprecated(tb, CTA_IP_MAX, attr, NULL, NULL);
+       ret = nla_parse_nested_deprecated(tb, CTA_IP_MAX, attr,
+                                         cta_ip_nla_policy, NULL);
        if (ret < 0)
                return ret;
 
-       ret = nla_validate_nested_deprecated(attr, CTA_IP_MAX,
-                                            cta_ip_nla_policy, NULL);
-       if (ret)
-               return ret;
-
        switch (tuple->src.l3num) {
        case NFPROTO_IPV4:
                ret = ipv4_nlattr_to_tuple(tb, tuple, flags);