netfilter: x_tables: kill check_entry helper

Once we add more sanity testing to xt_check_entry_offsets it
becomes relvant if we're expecting a 32bit 'config_compat' blob
or a normal one.

Since we already have a lot of similar-named functions (check_entry,
compat_check_entry, find_and_check_entry, etc.) and the current
incarnation is short just fold its contents into the callers.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/ipv6/netfilter/ip6_tables.c

@@ -599,15 +599,6 @@ static void cleanup_match(struct xt_entry_match *m, struct net *net)
 	module_put(par.match->me);
 }
 
-static int
-check_entry(const struct ip6t_entry *e)
-{
-	if (!ip6_checkentry(&e->ipv6))
-		return -EINVAL;
-
-	return xt_check_entry_offsets(e, e->target_offset, e->next_offset);
-}
-
 static int check_match(struct xt_entry_match *m, struct xt_mtchk_param *par)
 {
 	const struct ip6t_ip6 *ipv6 = par->entryinfo;
@@ -772,7 +763,10 @@ check_entry_size_and_hooks(struct ip6t_entry *e,
 		return -EINVAL;
 	}
 
-	err = check_entry(e);
+	if (!ip6_checkentry(&e->ipv6))
+		return -EINVAL;
+
+	err = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
 	if (err)
 		return err;
 
@@ -1528,8 +1522,10 @@ check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
 		return -EINVAL;
 	}
 
-	/* For purposes of check_entry casting the compat entry is fine */
-	ret = check_entry((struct ip6t_entry *)e);
+	if (!ip6_checkentry(&e->ipv6))
+		return -EINVAL;
+
+	ret = xt_check_entry_offsets(e, e->target_offset, e->next_offset);
 	if (ret)
 		return ret;