netfilter: conntrack: don't cache nlattr_tuple_size result in nla_size

We currently call ->nlattr_tuple_size() once at register time and
cache result in l4proto->nla_size.

nla_size is the only member that is written to, avoiding this would
allow to make l4proto trackers const.

We can use ->nlattr_tuple_size() at run time, and cache result in
the individual trackers instead.

This is an intermediate step, next patch removes nlattr_size()
callback and computes size at compile time, then removes nla_size.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/include/net/netfilter/nf_conntrack_l4proto.h b/include/net/netfilter/nf_conntrack_l4proto.h
index e065188..46e786f 100644 (file)
--- a/include/net/netfilter/nf_conntrack_l4proto.h
+++ b/include/net/netfilter/nf_conntrack_l4proto.h
@@ -74,7 +74,7 @@ struct nf_conntrack_l4proto {
        int (*tuple_to_nlattr)(struct sk_buff *skb,
                               const struct nf_conntrack_tuple *t);
        /* Calculate tuple nlattr size */
-       int (*nlattr_tuple_size)(void);
+       unsigned int (*nlattr_tuple_size)(void);
        int (*nlattr_to_tuple)(struct nlattr *tb[],
                               struct nf_conntrack_tuple *t);
        const struct nla_policy *nla_policy;
@@ -144,7 +144,7 @@ int nf_ct_port_tuple_to_nlattr(struct sk_buff *skb,
                               const struct nf_conntrack_tuple *tuple);
 int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[],
                               struct nf_conntrack_tuple *t);
-int nf_ct_port_nlattr_tuple_size(void);
+unsigned int nf_ct_port_nlattr_tuple_size(void);
 extern const struct nla_policy nf_ct_port_nla_policy[];
 
 #ifdef CONFIG_SYSCTL

diff --git a/net/ipv4/netfilter/nf_conntrack_proto_icmp.c b/net/ipv4/netfilter/nf_conntrack_proto_icmp.c
index 8969420..1849fed 100644 (file)
--- a/net/ipv4/netfilter/nf_conntrack_proto_icmp.c
+++ b/net/ipv4/netfilter/nf_conntrack_proto_icmp.c
@@ -258,9 +258,14 @@ static int icmp_nlattr_to_tuple(struct nlattr *tb[],
        return 0;
 }
 
-static int icmp_nlattr_tuple_size(void)
+static unsigned int icmp_nlattr_tuple_size(void)
 {
-       return nla_policy_len(icmp_nla_policy, CTA_PROTO_MAX + 1);
+       static unsigned int size __read_mostly;
+
+       if (!size)
+               size = nla_policy_len(icmp_nla_policy, CTA_PROTO_MAX + 1);
+
+       return size;
 }
 #endif
 

diff --git a/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c b/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
index dca921d..3ac0d82 100644 (file)
--- a/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
+++ b/net/ipv6/netfilter/nf_conntrack_proto_icmpv6.c
@@ -259,9 +259,14 @@ static int icmpv6_nlattr_to_tuple(struct nlattr *tb[],
        return 0;
 }
 
-static int icmpv6_nlattr_tuple_size(void)
+static unsigned int icmpv6_nlattr_tuple_size(void)
 {
-       return nla_policy_len(icmpv6_nla_policy, CTA_PROTO_MAX + 1);
+       static unsigned int size __read_mostly;
+
+       if (!size)
+               size = nla_policy_len(icmpv6_nla_policy, CTA_PROTO_MAX + 1);
+
+       return size;
 }
 #endif
 

diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index 28e6751..0e51694 100644 (file)
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -1563,9 +1563,14 @@ int nf_ct_port_nlattr_to_tuple(struct nlattr *tb[],
 }
 EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_to_tuple);
 
-int nf_ct_port_nlattr_tuple_size(void)
+unsigned int nf_ct_port_nlattr_tuple_size(void)
 {
-       return nla_policy_len(nf_ct_port_nla_policy, CTA_PROTO_MAX + 1);
+       static unsigned int size __read_mostly;
+
+       if (!size)
+               size = nla_policy_len(nf_ct_port_nla_policy, CTA_PROTO_MAX + 1);
+
+       return size;
 }
 EXPORT_SYMBOL_GPL(nf_ct_port_nlattr_tuple_size);
 #endif

diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index de4053d..6e0adfe 100644 (file)
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -533,11 +533,11 @@ nla_put_failure:
        return -1;
 }
 
-static inline size_t ctnetlink_proto_size(const struct nf_conn *ct)
+static size_t ctnetlink_proto_size(const struct nf_conn *ct)
 {
        const struct nf_conntrack_l3proto *l3proto;
        const struct nf_conntrack_l4proto *l4proto;
-       size_t len;
+       size_t len, len4 = 0;
 
        l3proto = __nf_ct_l3proto_find(nf_ct_l3num(ct));
        len = l3proto->nla_size;
@@ -545,8 +545,12 @@ static inline size_t ctnetlink_proto_size(const struct nf_conn *ct)
 
        l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
        len += l4proto->nla_size;
+       if (l4proto->nlattr_tuple_size) {
+               len4 = l4proto->nlattr_tuple_size();
+               len4 *= 3u; /* ORIG, REPLY, MASTER */
+       }
 
-       return len;
+       return len + len4;
 }
 
 static inline size_t ctnetlink_acct_size(const struct nf_conn *ct)

diff --git a/net/netfilter/nf_conntrack_proto.c b/net/netfilter/nf_conntrack_proto.c
index 83f739e..3b06ff3 100644 (file)
--- a/net/netfilter/nf_conntrack_proto.c
+++ b/net/netfilter/nf_conntrack_proto.c
@@ -398,8 +398,6 @@ int nf_ct_l4proto_register_one(struct nf_conntrack_l4proto *l4proto)
        l4proto->nla_size = 0;
        if (l4proto->nlattr_size)
                l4proto->nla_size += l4proto->nlattr_size();
-       if (l4proto->nlattr_tuple_size)
-               l4proto->nla_size += 3 * l4proto->nlattr_tuple_size();
 
        rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
                           l4proto);

diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c
index 8f28329..b12fc07 100644 (file)
--- a/net/netfilter/nf_conntrack_proto_tcp.c
+++ b/net/netfilter/nf_conntrack_proto_tcp.c
@@ -1277,9 +1277,14 @@ static int tcp_nlattr_size(void)
                + nla_policy_len(tcp_nla_policy, CTA_PROTOINFO_TCP_MAX + 1);
 }
 
-static int tcp_nlattr_tuple_size(void)
+static unsigned int tcp_nlattr_tuple_size(void)
 {
-       return nla_policy_len(nf_ct_port_nla_policy, CTA_PROTO_MAX + 1);
+       static unsigned int size __read_mostly;
+
+       if (!size)
+               size = nla_policy_len(nf_ct_port_nla_policy, CTA_PROTO_MAX + 1);
+
+       return size;
 }
 #endif