[NETFILTER]: nf_conntrack: sysctl compatibility with old connection tracking

This patch adds an option to keep the connection tracking sysctls visible
under their old names.

Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/net/netfilter/nf_conntrack_proto_generic.c b/net/netfilter/nf_conntrack_proto_generic.c
index 15306b9..6990253 100644
--- a/net/netfilter/nf_conntrack_proto_generic.c
+++ b/net/netfilter/nf_conntrack_proto_generic.c
@@ -86,6 +86,21 @@
 		.ctl_name	= 0
 	}
 };
+#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
+static struct ctl_table generic_compat_sysctl_table[] = {
+	{
+		.ctl_name	= NET_IPV4_NF_CONNTRACK_GENERIC_TIMEOUT,
+		.procname	= "ip_conntrack_generic_timeout",
+		.data		= &nf_ct_generic_timeout,
+		.maxlen		= sizeof(unsigned int),
+		.mode		= 0644,
+		.proc_handler	= &proc_dointvec_jiffies,
+	},
+	{
+		.ctl_name	= 0
+	}
+};
+#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
 #endif /* CONFIG_SYSCTL */
 
 struct nf_conntrack_l4proto nf_conntrack_l4proto_generic =
@@ -102,5 +117,8 @@
 #ifdef CONFIG_SYSCTL
 	.ctl_table_header	= &generic_sysctl_header,
 	.ctl_table		= generic_sysctl_table,
+#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
+	.ctl_compat_table	= generic_compat_sysctl_table,
+#endif
 #endif
 };