[NETFILTER]: ipt_hashlimit: add compat conversion functions

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/netfilter/ipt_hashlimit.c

@@ -535,10 +535,39 @@ hashlimit_destroy(const struct xt_match *match, void *matchinfo)
 	htable_put(r->hinfo);
 }
 
+#ifdef CONFIG_COMPAT
+struct compat_ipt_hashlimit_info {
+	char name[IFNAMSIZ];
+	struct hashlimit_cfg cfg;
+	compat_uptr_t hinfo;
+	compat_uptr_t master;
+};
+
+static void compat_from_user(void *dst, void *src)
+{
+	int off = offsetof(struct compat_ipt_hashlimit_info, hinfo);
+
+	memcpy(dst, src, off);
+	memset(dst + off, 0, sizeof(struct compat_ipt_hashlimit_info) - off);
+}
+
+static int compat_to_user(void __user *dst, void *src)
+{
+	int off = offsetof(struct compat_ipt_hashlimit_info, hinfo);
+
+	return copy_to_user(dst, src, off) ? -EFAULT : 0;
+}
+#endif
+
 static struct ipt_match ipt_hashlimit = {
 	.name		= "hashlimit",
 	.match		= hashlimit_match,
 	.matchsize	= sizeof(struct ipt_hashlimit_info),
+#ifdef CONFIG_COMPAT
+	.compatsize	= sizeof(struct compat_ipt_hashlimit_info),
+	.compat_from_user = compat_from_user,
+	.compat_to_user	= compat_to_user,
+#endif
 	.checkentry	= hashlimit_checkentry,
 	.destroy	= hashlimit_destroy,
 	.me		= THIS_MODULE