netfilter: nf_conntrack: push zone object into functions

This patch replaces the zone id which is pushed down into functions
with the actual zone object. It's a bigger one-time change, but
needed for later on extending zones with a direction parameter, and
thus decoupling this additional information from all call-sites.

No functional changes in this patch.

The default zone becomes a global const object, namely nf_ct_zone_dflt
and will be returned directly in various cases, one being, when there's
f.e. no zoning support.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/nf_synproxy_core.c b/net/netfilter/nf_synproxy_core.c
index 71f1e9f..58b2e84 100644
--- a/net/netfilter/nf_synproxy_core.c
+++ b/net/netfilter/nf_synproxy_core.c
@@ -17,10 +17,12 @@
 #include <linux/netfilter/x_tables.h>
 #include <linux/netfilter/xt_tcpudp.h>
 #include <linux/netfilter/xt_SYNPROXY.h>
+
 #include <net/netfilter/nf_conntrack.h>
 #include <net/netfilter/nf_conntrack_extend.h>
 #include <net/netfilter/nf_conntrack_seqadj.h>
 #include <net/netfilter/nf_conntrack_synproxy.h>
+#include <net/netfilter/nf_conntrack_zones.h>
 
 int synproxy_net_id;
 EXPORT_SYMBOL_GPL(synproxy_net_id);
@@ -352,7 +354,7 @@
 	struct nf_conn *ct;
 	int err = -ENOMEM;
 
-	ct = nf_ct_tmpl_alloc(net, 0, GFP_KERNEL);
+	ct = nf_ct_tmpl_alloc(net, &nf_ct_zone_dflt, GFP_KERNEL);
 	if (IS_ERR(ct)) {
 		err = PTR_ERR(ct);
 		goto err1;