Re: [PATCH 1/1] ipvs: kernel oops - do_ip_vs_get_ctl

[Jesper Dangaard Brouer <brouer@redhat.com>]

Hi Hans,

Thank you for your work.
Just some whitespace nitpicks below.

I have not been able to reproduce the bug in:
  https://bugzilla.redhat.com/show_bug.cgi?id=806704

Can you recommend a (better) way to reproduce this bug?
I just want to be able to verify that this fixes the bug in question.


On Wed, 2012-04-25 at 09:44 +0200, Hans Schillstrom wrote:
> Change order of init so netns init is ready
> when register ioctl and netlink.
> 
> Reported-by: "Ryan O'Hara" <rohara@redhat.com>
> Signed-off-by: Hans Schillstrom <hans.schillstrom@ericsson.com>
> ---
>  include/net/ip_vs.h             |    2 +
>  net/netfilter/ipvs/ip_vs_core.c |    9 ++++++
>  net/netfilter/ipvs/ip_vs_ctl.c  |   52 ++++++++++++++++++++++----------------
>  3 files changed, 41 insertions(+), 22 deletions(-)
> 
> diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
> index f967395..93b81aa 100644
> --- a/include/net/ip_vs.h
> +++ b/include/net/ip_vs.h
> @@ -1201,6 +1201,8 @@ ip_vs_lookup_real_service(struct net *net, int af, __u16 protocol,
>  
>  extern int ip_vs_use_count_inc(void);
>  extern void ip_vs_use_count_dec(void);
> +extern int ip_vs_register_nl_ioctl(void);
> +extern void ip_vs_unregister_nl_ioctl(void);
>  extern int ip_vs_control_init(void);
>  extern void ip_vs_control_cleanup(void);
>  extern struct ip_vs_dest *
> diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c
> index d8b1d30..c8f36b9 100644
> --- a/net/netfilter/ipvs/ip_vs_core.c
> +++ b/net/netfilter/ipvs/ip_vs_core.c
> @@ -1995,10 +1995,18 @@ static int __init ip_vs_init(void)
>  		goto cleanup_dev;
>  	}
>  
> +	ret = ip_vs_register_nl_ioctl();
> +	if (ret < 0) {
> +		pr_err("can't register netlink/ioctl.\n");
> +		goto cleanup_hooks;
> +	}
> +
>  	pr_info("ipvs loaded.\n");
>  
>  	return ret;
>  
> +cleanup_hooks:
> +	nf_unregister_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
>  cleanup_dev:
>  	unregister_pernet_device(&ipvs_core_dev_ops);
>  cleanup_sub:
> @@ -2014,6 +2022,7 @@ exit:
>  
>  static void __exit ip_vs_cleanup(void)
>  {
> +	ip_vs_unregister_nl_ioctl();
>  	nf_unregister_hooks(ip_vs_ops, ARRAY_SIZE(ip_vs_ops));
>  	unregister_pernet_device(&ipvs_core_dev_ops);
>  	unregister_pernet_subsys(&ipvs_core_ops);	/* free ip_vs struct */
> diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
> index 7131417..efaf484 100644
> --- a/net/netfilter/ipvs/ip_vs_ctl.c
> +++ b/net/netfilter/ipvs/ip_vs_ctl.c
> @@ -3750,21 +3750,10 @@ void __net_exit ip_vs_control_net_cleanup(struct net *net)
>  	free_percpu(ipvs->tot_stats.cpustats);
>  }
>  
> -int __init ip_vs_control_init(void)
> +int ip_vs_register_nl_ioctl(void)
>  {
> -	int idx;
>  	int ret;
>  
> -	EnterFunction(2);
> -
> -	/* Initialize svc_table, ip_vs_svc_fwm_table, rs_table */
> -	for(idx = 0; idx < IP_VS_SVC_TAB_SIZE; idx++)  {
> -		INIT_LIST_HEAD(&ip_vs_svc_table[idx]);
> -		INIT_LIST_HEAD(&ip_vs_svc_fwm_table[idx]);
> -	}
> -
> -	smp_wmb();	/* Do we really need it now ? */
> -
>  	ret = nf_register_sockopt(&ip_vs_sockopts);
>  	if (ret) {
>  		pr_err("cannot register sockopt.\n");
> @@ -3776,28 +3765,47 @@ int __init ip_vs_control_init(void)
>  		pr_err("cannot register Generic Netlink interface.\n");
>  		goto err_genl;
>  	}
> -
> -	ret = register_netdevice_notifier(&ip_vs_dst_notifier);
> -	if (ret < 0)
> -		goto err_notf;
> -
> -	LeaveFunction(2);
>  	return 0;
>  
> -err_notf:
> -	ip_vs_genl_unregister();
>  err_genl:
>  	nf_unregister_sockopt(&ip_vs_sockopts);
>  err_sock:
>  	return ret;
>  }
>  
> +void ip_vs_unregister_nl_ioctl(void) 

There is a extra trailing whitespace behind
ip_vs_unregister_nl_ioctl(void)


> +{
> +	ip_vs_genl_unregister();
> +	nf_unregister_sockopt(&ip_vs_sockopts);
> +}
> +
> +int __init ip_vs_control_init(void)
> +{
> +	int idx;
> +	int ret;
> +
> +	EnterFunction(2);
> +
> +	/* Initialize svc_table, ip_vs_svc_fwm_table, rs_table */
> +	for(idx = 0; idx < IP_VS_SVC_TAB_SIZE; idx++)  {

The for loop is funny spaced...


> +		INIT_LIST_HEAD(&ip_vs_svc_table[idx]);
> +		INIT_LIST_HEAD(&ip_vs_svc_fwm_table[idx]);
> +	}
> +
> +	smp_wmb();	/* Do we really need it now ? */
> +
> +	ret = register_netdevice_notifier(&ip_vs_dst_notifier);
> +	if (ret < 0)
> +		return ret;
> +
> +	LeaveFunction(2);
> +	return 0;
> +}
> +
>  
>  void ip_vs_control_cleanup(void)
>  {
>  	EnterFunction(2);
>  	unregister_netdevice_notifier(&ip_vs_dst_notifier);
> -	ip_vs_genl_unregister();
> -	nf_unregister_sockopt(&ip_vs_sockopts);
>  	LeaveFunction(2);
>  }

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Sr. Network Kernel Developer at Red Hat
  Author of http://www.iptv-analyzer.org
  LinkedIn: http://www.linkedin.com/in/brouer