Subject: Re: [PATCH 02/12] netfilter: don't register sysctl when register proto

From: Pablo Neira Ayuso <[email-masked]>
Date: Tue, 17 Apr 2012 10:56:17 +0200

On Tue, Apr 17, 2012 at 10:56:13AM +0800, Gao feng wrote:
> delete nf_ct_l[3,4]proto_register_sysctl when register l[3,4]proto.
> and add nf_ct_register_net_sysctl,nf_ct_unregister_net_sysctl to
> register the sysctl for net namespace.
> 
> Signed-off-by: Gao feng <[email-masked]>
> ---
>  net/netfilter/nf_conntrack_proto.c |  109 +++++-------------------------------
>  1 files changed, 15 insertions(+), 94 deletions(-)
> 
> diff --git a/net/netfilter/nf_conntrack_proto.c b/net/netfilter/nf_conntrack_proto.c
> index be3da2c..207cdd8 100644
> --- a/net/netfilter/nf_conntrack_proto.c
> +++ b/net/netfilter/nf_conntrack_proto.c
> @@ -35,12 +35,15 @@ EXPORT_SYMBOL_GPL(nf_ct_l3protos);
>  static DEFINE_MUTEX(nf_ct_proto_mutex);
>  
>  #ifdef CONFIG_SYSCTL
> -static int
> -nf_ct_register_sysctl(struct ctl_table_header **header, struct ctl_path *path,
> -		      struct ctl_table *table, unsigned int *users)
> +int
> +nf_ct_register_net_sysctl(struct net *net, 
> +			  struct ctl_table_header **header,
> +			  struct ctl_path *path,
> +			  struct ctl_table *table,
> +			  unsigned int *users)

Please, don't rename this function. Just add the *net parameter
instead.

>  {
>  	if (*header == NULL) {
> -		*header = register_sysctl_paths(path, table);
> +		*header = register_net_sysctl_table(net, path, table);
>  		if (*header == NULL)
>  			return -ENOMEM;
>  	}
> @@ -48,17 +51,21 @@ nf_ct_register_sysctl(struct ctl_table_header **header, struct ctl_path *path,
>  		(*users)++;
>  	return 0;
>  }
> +EXPORT_SYMBOL_GPL(nf_ct_register_net_sysctl);
>  
> -static void
> -nf_ct_unregister_sysctl(struct ctl_table_header **header,
> -			struct ctl_table *table, unsigned int *users)
> +void
> +nf_ct_unregister_net_sysctl(struct ctl_table_header **header,
> +			    struct ctl_table *table,
> +			    unsigned int *users)
>  {
>  	if (users != NULL && --*users > 0)
>  		return;
>  
>  	unregister_sysctl_table(*header);
> +	kfree(table);
>  	*header = NULL;
>  }
> +EXPORT_SYMBOL_GPL(nf_ct_unregister_net_sysctl);
>  #endif
>  
>  struct nf_conntrack_l4proto *
> @@ -161,29 +168,6 @@ static int kill_l4proto(struct nf_conn *i, void *data)
>  	       nf_ct_l3num(i) == l4proto->l3proto;
>  }
>  
> -static int nf_ct_l3proto_register_sysctl(struct nf_conntrack_l3proto *l3proto)
> -{
> -	int err = 0;
> -
> -#ifdef CONFIG_SYSCTL
> -	if (l3proto->ctl_table != NULL) {
> -		err = nf_ct_register_sysctl(&l3proto->ctl_table_header,
> -					    l3proto->ctl_table_path,
> -					    l3proto->ctl_table, NULL);
> -	}
> -#endif
> -	return err;
> -}
> -
> -static void nf_ct_l3proto_unregister_sysctl(struct nf_conntrack_l3proto *l3proto)
> -{
> -#ifdef CONFIG_SYSCTL
> -	if (l3proto->ctl_table_header != NULL)
> -		nf_ct_unregister_sysctl(&l3proto->ctl_table_header,
> -					l3proto->ctl_table, NULL);
> -#endif
> -}
> -
>  int nf_conntrack_l3proto_register(struct nf_conntrack_l3proto *proto)
>  {
>  	int ret = 0;
> @@ -203,10 +187,6 @@ int nf_conntrack_l3proto_register(struct nf_conntrack_l3proto *proto)
>  		goto out_unlock;
>  	}
>  
> -	ret = nf_ct_l3proto_register_sysctl(proto);
> -	if (ret < 0)
> -		goto out_unlock;
> -
>  	if (proto->nlattr_tuple_size)
>  		proto->nla_size = 3 * proto->nlattr_tuple_size();
>  
> @@ -230,7 +210,6 @@ void nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto)
>  					 ) != proto);
>  	rcu_assign_pointer(nf_ct_l3protos[proto->l3proto],
>  			   &nf_conntrack_l3proto_generic);
> -	nf_ct_l3proto_unregister_sysctl(proto);
>  	mutex_unlock(&nf_ct_proto_mutex);
>  
>  	synchronize_rcu();
> @@ -243,52 +222,6 @@ void nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto)
>  }
>  EXPORT_SYMBOL_GPL(nf_conntrack_l3proto_unregister);
>  
> -static int nf_ct_l4proto_register_sysctl(struct nf_conntrack_l4proto *l4proto)
> -{
> -	int err = 0;
> -
> -#ifdef CONFIG_SYSCTL
> -	if (l4proto->ctl_table != NULL) {
> -		err = nf_ct_register_sysctl(l4proto->ctl_table_header,
> -					    nf_net_netfilter_sysctl_path,
> -					    l4proto->ctl_table,
> -					    l4proto->ctl_table_users);
> -		if (err < 0)
> -			goto out;
> -	}
> -#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
> -	if (l4proto->ctl_compat_table != NULL) {
> -		err = nf_ct_register_sysctl(&l4proto->ctl_compat_table_header,
> -					    nf_net_ipv4_netfilter_sysctl_path,
> -					    l4proto->ctl_compat_table, NULL);
> -		if (err == 0)
> -			goto out;
> -		nf_ct_unregister_sysctl(l4proto->ctl_table_header,
> -					l4proto->ctl_table,
> -					l4proto->ctl_table_users);
> -	}
> -#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
> -out:
> -#endif /* CONFIG_SYSCTL */
> -	return err;
> -}
> -
> -static void nf_ct_l4proto_unregister_sysctl(struct nf_conntrack_l4proto *l4proto)
> -{
> -#ifdef CONFIG_SYSCTL
> -	if (l4proto->ctl_table_header != NULL &&
> -	    *l4proto->ctl_table_header != NULL)
> -		nf_ct_unregister_sysctl(l4proto->ctl_table_header,
> -					l4proto->ctl_table,
> -					l4proto->ctl_table_users);
> -#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
> -	if (l4proto->ctl_compat_table_header != NULL)
> -		nf_ct_unregister_sysctl(&l4proto->ctl_compat_table_header,
> -					l4proto->ctl_compat_table, NULL);
> -#endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
> -#endif /* CONFIG_SYSCTL */
> -}
> -

Where did this function go?

>  /* FIXME: Allow NULL functions and sub in pointers to generic for
>     them. --RR */
>  int nf_conntrack_l4proto_register(struct nf_conntrack_l4proto *l4proto)
> @@ -333,10 +266,6 @@ int nf_conntrack_l4proto_register(struct nf_conntrack_l4proto *l4proto)
>  		goto out_unlock;
>  	}
>  
> -	ret = nf_ct_l4proto_register_sysctl(l4proto);
> -	if (ret < 0)
> -		goto out_unlock;
> -
>  	l4proto->nla_size = 0;
>  	if (l4proto->nlattr_size)
>  		l4proto->nla_size += l4proto->nlattr_size();
> @@ -365,7 +294,6 @@ void nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *l4proto)
>  			) != l4proto);
>  	rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
>  			   &nf_conntrack_l4proto_generic);
> -	nf_ct_l4proto_unregister_sysctl(l4proto);
>  	mutex_unlock(&nf_ct_proto_mutex);
>  
>  	synchronize_rcu();
> @@ -380,12 +308,7 @@ EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_unregister);
>  
>  int nf_conntrack_proto_init(void)
>  {
> -	unsigned int i;
> -	int err;
> -
> -	err = nf_ct_l4proto_register_sysctl(&nf_conntrack_l4proto_generic);
> -	if (err < 0)
> -		return err;
> +	unsigned int i;	
>  
>  	for (i = 0; i < AF_MAX; i++)
>  		rcu_assign_pointer(nf_ct_l3protos[i],
> @@ -397,8 +320,6 @@ void nf_conntrack_proto_fini(void)
>  {
>  	unsigned int i;
>  
> -	nf_ct_l4proto_unregister_sysctl(&nf_conntrack_l4proto_generic);
> -
>  	/* free l3proto protocol tables */
>  	for (i = 0; i < PF_MAX; i++)
>  		kfree(nf_ct_protos[i]);
> -- 
> 1.7.7.6
>