netfilter: x_tables: remove paranoia tests

No need for these.
There is only one caller, the xtables core, when the table is registered
for the first time with a particular network namespace.

After ->table_init() call, the table is linked into the tables[af] list,
so next call to that function will skip the ->table_init().
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/ipv4/netfilter/arptable_filter.c

@@ -44,9 +44,6 @@ static int __net_init arptable_filter_table_init(struct net *net)
 	struct arpt_replace *repl;
 	int err;
 
-	if (net->ipv4.arptable_filter)
-		return 0;
-
 	repl = arpt_alloc_initial_table(&packet_filter);
 	if (repl == NULL)
 		return -ENOMEM;

net/ipv4/netfilter/iptable_filter.c

@@ -48,9 +48,6 @@ static int __net_init iptable_filter_table_init(struct net *net)
 	struct ipt_replace *repl;
 	int err;
 
-	if (net->ipv4.iptable_filter)
-		return 0;
-
 	repl = ipt_alloc_initial_table(&packet_filter);
 	if (repl == NULL)
 		return -ENOMEM;

net/ipv4/netfilter/iptable_mangle.c

@@ -88,9 +88,6 @@ static int __net_init iptable_mangle_table_init(struct net *net)
 	struct ipt_replace *repl;
 	int ret;
 
-	if (net->ipv4.iptable_mangle)
-		return 0;
-
 	repl = ipt_alloc_initial_table(&packet_mangler);
 	if (repl == NULL)
 		return -ENOMEM;

net/ipv4/netfilter/iptable_nat.c

@@ -90,9 +90,6 @@ static int __net_init iptable_nat_table_init(struct net *net)
 	struct ipt_replace *repl;
 	int ret;
 
-	if (net->ipv4.nat_table)
-		return 0;
-
 	repl = ipt_alloc_initial_table(&nf_nat_ipv4_table);
 	if (repl == NULL)
 		return -ENOMEM;

net/ipv4/netfilter/iptable_raw.c

@@ -55,9 +55,6 @@ static int __net_init iptable_raw_table_init(struct net *net)
 	if (raw_before_defrag)
 		table = &packet_raw_before_defrag;
 
-	if (net->ipv4.iptable_raw)
-		return 0;
-
 	repl = ipt_alloc_initial_table(table);
 	if (repl == NULL)
 		return -ENOMEM;

net/ipv4/netfilter/iptable_security.c

@@ -50,9 +50,6 @@ static int __net_init iptable_security_table_init(struct net *net)
 	struct ipt_replace *repl;
 	int ret;
 
-	if (net->ipv4.iptable_security)
-		return 0;
-
 	repl = ipt_alloc_initial_table(&security_table);
 	if (repl == NULL)
 		return -ENOMEM;

net/ipv6/netfilter/ip6table_filter.c

@@ -49,9 +49,6 @@ static int __net_init ip6table_filter_table_init(struct net *net)
 	struct ip6t_replace *repl;
 	int err;
 
-	if (net->ipv6.ip6table_filter)
-		return 0;
-
 	repl = ip6t_alloc_initial_table(&packet_filter);
 	if (repl == NULL)
 		return -ENOMEM;

net/ipv6/netfilter/ip6table_mangle.c

@@ -81,9 +81,6 @@ static int __net_init ip6table_mangle_table_init(struct net *net)
 	struct ip6t_replace *repl;
 	int ret;
 
-	if (net->ipv6.ip6table_mangle)
-		return 0;
-
 	repl = ip6t_alloc_initial_table(&packet_mangler);
 	if (repl == NULL)
 		return -ENOMEM;

net/ipv6/netfilter/ip6table_nat.c

@@ -92,9 +92,6 @@ static int __net_init ip6table_nat_table_init(struct net *net)
 	struct ip6t_replace *repl;
 	int ret;
 
-	if (net->ipv6.ip6table_nat)
-		return 0;
-
 	repl = ip6t_alloc_initial_table(&nf_nat_ipv6_table);
 	if (repl == NULL)
 		return -ENOMEM;

net/ipv6/netfilter/ip6table_raw.c

@@ -54,9 +54,6 @@ static int __net_init ip6table_raw_table_init(struct net *net)
 	if (raw_before_defrag)
 		table = &packet_raw_before_defrag;
 
-	if (net->ipv6.ip6table_raw)
-		return 0;
-
 	repl = ip6t_alloc_initial_table(table);
 	if (repl == NULL)
 		return -ENOMEM;

net/ipv6/netfilter/ip6table_security.c

@@ -49,9 +49,6 @@ static int __net_init ip6table_security_table_init(struct net *net)
 	struct ip6t_replace *repl;
 	int ret;
 
-	if (net->ipv6.ip6table_security)
-		return 0;
-
 	repl = ip6t_alloc_initial_table(&security_table);
 	if (repl == NULL)
 		return -ENOMEM;