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: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Patrick McHardy 2011-12-23 14:00:49 +01:00 committed by Pablo Neira Ayuso
parent 329fb58a93
commit d70308f78b
10 changed files with 3 additions and 32 deletions

View File

@ -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,

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@ -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;
}

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@ -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,

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@ -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,

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@ -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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@ -70,7 +70,6 @@ sctp_manip_pkt(struct sk_buff *skb,
static const struct nf_nat_protocol nf_nat_protocol_sctp = {
.protonum = IPPROTO_SCTP,
.me = THIS_MODULE,
.manip_pkt = sctp_manip_pkt,
.in_range = nf_nat_proto_in_range,
.unique_tuple = sctp_unique_tuple,

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@ -82,7 +82,6 @@ tcp_manip_pkt(struct sk_buff *skb,
const struct nf_nat_protocol nf_nat_protocol_tcp = {
.protonum = IPPROTO_TCP,
.me = THIS_MODULE,
.manip_pkt = tcp_manip_pkt,
.in_range = nf_nat_proto_in_range,
.unique_tuple = tcp_unique_tuple,

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@ -73,7 +73,6 @@ udp_manip_pkt(struct sk_buff *skb,
const struct nf_nat_protocol nf_nat_protocol_udp = {
.protonum = IPPROTO_UDP,
.me = THIS_MODULE,
.manip_pkt = udp_manip_pkt,
.in_range = nf_nat_proto_in_range,
.unique_tuple = udp_unique_tuple,

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@ -72,7 +72,6 @@ udplite_manip_pkt(struct sk_buff *skb,
static const struct nf_nat_protocol nf_nat_protocol_udplite = {
.protonum = IPPROTO_UDPLITE,
.me = THIS_MODULE,
.manip_pkt = udplite_manip_pkt,
.in_range = nf_nat_proto_in_range,
.unique_tuple = udplite_unique_tuple,

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@ -46,7 +46,6 @@ unknown_manip_pkt(struct sk_buff *skb,
}
const struct nf_nat_protocol nf_nat_unknown_protocol = {
/* .me isn't set: getting a ref to this cannot fail. */
.manip_pkt = unknown_manip_pkt,
.in_range = unknown_in_range,
.unique_tuple = unknown_unique_tuple,