Commit d70308f7 authored by Patrick McHardy's avatar Patrick McHardy Committed by Pablo Neira Ayuso
Browse files

netfilter: nat: remove module reference counting from NAT protocols 



The only remaining user of NAT protocol module reference counting is NAT
ctnetlink support. Since this is a fairly short sequence of code, convert
over to use RCU and remove module reference counting.

Module unregistration is already protected by RCU using synchronize_rcu(),
so no further changes are necessary.

Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent 329fb58a

include/net/netfilter/nf_nat_protocol.h

+0 −2
Original line number Diff line number Diff line
@@ -10,8 +10,6 @@ struct nf_nat_protocol { 
	/* Protocol number. */

	unsigned int protonum;



	struct module *me;



	/* Translate a packet to the target according to manip type.

	   Return true if succeeded. */

	bool (*manip_pkt)(struct sk_buff *skb,

net/ipv4/netfilter/nf_nat_core.c

+3 −22
Original line number Diff line number Diff line
@@ -575,26 +575,6 @@ static struct nf_ct_ext_type nat_extend __read_mostly = { 
#include <linux/netfilter/nfnetlink.h>

#include <linux/netfilter/nfnetlink_conntrack.h>



static const struct nf_nat_protocol *

nf_nat_proto_find_get(u_int8_t protonum)

{

	const struct nf_nat_protocol *p;



	rcu_read_lock();

	p = __nf_nat_proto_find(protonum);

	if (!try_module_get(p->me))

		p = &nf_nat_unknown_protocol;

	rcu_read_unlock();



	return p;

}



static void

nf_nat_proto_put(const struct nf_nat_protocol *p)

{

	module_put(p->me);

}



static const struct nla_policy protonat_nla_policy[CTA_PROTONAT_MAX+1] = {

	[CTA_PROTONAT_PORT_MIN]	= { .type = NLA_U16 },

	[CTA_PROTONAT_PORT_MAX]	= { .type = NLA_U16 },
@@ -612,10 +592,11 @@ static int nfnetlink_parse_nat_proto(struct nlattr *attr, 
	if (err < 0)

		return err;



	npt = nf_nat_proto_find_get(nf_ct_protonum(ct));

	rcu_read_lock();

	npt = __nf_nat_proto_find(nf_ct_protonum(ct));

	if (npt->nlattr_to_range)

		err = npt->nlattr_to_range(tb, range);

	nf_nat_proto_put(npt);

	rcu_read_unlock();

	return err;

}

net/ipv4/netfilter/nf_nat_proto_dccp.c

+0 −1
Original line number Diff line number Diff line
@@ -80,7 +80,6 @@ dccp_manip_pkt(struct sk_buff *skb, 


static const struct nf_nat_protocol nf_nat_protocol_dccp = {

	.protonum		= IPPROTO_DCCP,

	.me			= THIS_MODULE,

	.manip_pkt		= dccp_manip_pkt,

	.in_range		= nf_nat_proto_in_range,

	.unique_tuple		= dccp_unique_tuple,

net/ipv4/netfilter/nf_nat_proto_gre.c

+0 −1
Original line number Diff line number Diff line
@@ -119,7 +119,6 @@ gre_manip_pkt(struct sk_buff *skb, unsigned int iphdroff, 


static const struct nf_nat_protocol gre = {

	.protonum		= IPPROTO_GRE,

	.me			= THIS_MODULE,

	.manip_pkt		= gre_manip_pkt,

	.in_range		= nf_nat_proto_in_range,

	.unique_tuple		= gre_unique_tuple,

net/ipv4/netfilter/nf_nat_proto_icmp.c

+0 −1
Original line number Diff line number Diff line
@@ -74,7 +74,6 @@ icmp_manip_pkt(struct sk_buff *skb, 


const struct nf_nat_protocol nf_nat_protocol_icmp = {

	.protonum		= IPPROTO_ICMP,

	.me			= THIS_MODULE,

	.manip_pkt		= icmp_manip_pkt,

	.in_range		= icmp_in_range,

	.unique_tuple		= icmp_unique_tuple,

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