[PATCH] do not give access to 1-1024 ports for autobinding

[PATCH] do not give access to 1-1024 ports for autobinding

[Denis V. Lunev]

This patch prevents possibility to give 1-1024 port range for autobinding.
{1, 1} may only takes some sense for deep embedded people.

Signed-off-by: Denis V. Lunev <den@openvz.org>

--- ./net/ipv4/sysctl_net_ipv4.c.port2	2007-10-10 17:46:48.000000000 +0400
+++ ./net/ipv4/sysctl_net_ipv4.c	2007-10-10 18:08:00.000000000 +0400
@@ -25,7 +25,7 @@ extern int sysctl_ip_nonlocal_bind;
 #ifdef CONFIG_SYSCTL
 static int zero;
 static int tcp_retr1_max = 255;
-static int ip_local_port_range_min[] = { 1, 1 };
+static int ip_local_port_range_min[] = { 1024, 1024 };
 static int ip_local_port_range_max[] = { 65535, 65535 };
 #endif
 

Re: [PATCH] do not give access to 1-1024 ports for autobinding

[Stephen Hemminger]

On Wed, 10 Oct 2007 18:34:49 +0400
"Denis V. Lunev" <den@openvz.org> wrote:

> This patch prevents possibility to give 1-1024 port range for autobinding.
> {1, 1} may only takes some sense for deep embedded people.
> 
> Signed-off-by: Denis V. Lunev <den@openvz.org>
> 
> --- ./net/ipv4/sysctl_net_ipv4.c.port2	2007-10-10 17:46:48.000000000 +0400
> +++ ./net/ipv4/sysctl_net_ipv4.c	2007-10-10 18:08:00.000000000 +0400
> @@ -25,7 +25,7 @@ extern int sysctl_ip_nonlocal_bind;
>  #ifdef CONFIG_SYSCTL
>  static int zero;
>  static int tcp_retr1_max = 255;
> -static int ip_local_port_range_min[] = { 1, 1 };
> +static int ip_local_port_range_min[] = { 1024, 1024 };
>  static int ip_local_port_range_max[] = { 65535, 65535 };
>  #endif
>  
> -

That only limits the sysctl, which seems completely counter productive.
Sounds like more of the "stop root from shooting themselves" patches.

-- 
Stephen Hemminger <shemminger@linux-foundation.org>

Re: [PATCH] do not give access to 1-1024 ports for autobinding

[Denis V. Lunev]

Stephen Hemminger wrote:
> On Wed, 10 Oct 2007 18:34:49 +0400
> "Denis V. Lunev" <den@openvz.org> wrote:
> 
>> This patch prevents possibility to give 1-1024 port range for autobinding.
>> {1, 1} may only takes some sense for deep embedded people.
>>
>> Signed-off-by: Denis V. Lunev <den@openvz.org>
>>
>> --- ./net/ipv4/sysctl_net_ipv4.c.port2	2007-10-10 17:46:48.000000000 +0400
>> +++ ./net/ipv4/sysctl_net_ipv4.c	2007-10-10 18:08:00.000000000 +0400
>> @@ -25,7 +25,7 @@ extern int sysctl_ip_nonlocal_bind;
>>  #ifdef CONFIG_SYSCTL
>>  static int zero;
>>  static int tcp_retr1_max = 255;
>> -static int ip_local_port_range_min[] = { 1, 1 };
>> +static int ip_local_port_range_min[] = { 1024, 1024 };
>>  static int ip_local_port_range_max[] = { 65535, 65535 };
>>  #endif
>>  
>> -
> 
> That only limits the sysctl, which seems completely counter productive.
> Sounds like more of the "stop root from shooting themselves" patches.
> 

They have sense for the case of multiple network namespaces, where root
in the other namespace can be treated as a user to initial namespace.

Re: [PATCH] do not give access to 1-1024 ports for autobinding

[Stephen Hemminger]

On Wed, 10 Oct 2007 20:59:13 +0400
"Denis V. Lunev" <dlunev@gmail.com> wrote:

> Stephen Hemminger wrote:
> > On Wed, 10 Oct 2007 18:34:49 +0400
> > "Denis V. Lunev" <den@openvz.org> wrote:
> > 
> >> This patch prevents possibility to give 1-1024 port range for autobinding.
> >> {1, 1} may only takes some sense for deep embedded people.
> >>
> >> Signed-off-by: Denis V. Lunev <den@openvz.org>
> >>
> >> --- ./net/ipv4/sysctl_net_ipv4.c.port2	2007-10-10 17:46:48.000000000 +0400
> >> +++ ./net/ipv4/sysctl_net_ipv4.c	2007-10-10 18:08:00.000000000 +0400
> >> @@ -25,7 +25,7 @@ extern int sysctl_ip_nonlocal_bind;
> >>  #ifdef CONFIG_SYSCTL
> >>  static int zero;
> >>  static int tcp_retr1_max = 255;
> >> -static int ip_local_port_range_min[] = { 1, 1 };
> >> +static int ip_local_port_range_min[] = { 1024, 1024 };
> >>  static int ip_local_port_range_max[] = { 65535, 65535 };
> >>  #endif
> >>  
> >> -
> > 
> > That only limits the sysctl, which seems completely counter productive.
> > Sounds like more of the "stop root from shooting themselves" patches.
> > 
> 
> They have sense for the case of multiple network namespaces, where root
> in the other namespace can be treated as a user to initial namespace.

IMHO  don't want to treat root as a complete idiot like normal users.
As long as what root requests doesn't create a security problem, it
should be allowed.  The port space is per namespace right? The sysctl
values should be per namespace as well.

-- 
Stephen Hemminger <shemminger@linux-foundation.org>

Re: [PATCH] do not give access to 1-1024 ports for autobinding

[David Miller]

From: Stephen Hemminger <shemminger@linux-foundation.org>
Date: Wed, 10 Oct 2007 08:41:37 -0700

> On Wed, 10 Oct 2007 18:34:49 +0400
> "Denis V. Lunev" <den@openvz.org> wrote:
> 
> > This patch prevents possibility to give 1-1024 port range for autobinding.
> > {1, 1} may only takes some sense for deep embedded people.
> > 
> > Signed-off-by: Denis V. Lunev <den@openvz.org>
> > 
> > --- ./net/ipv4/sysctl_net_ipv4.c.port2	2007-10-10 17:46:48.000000000 +0400
> > +++ ./net/ipv4/sysctl_net_ipv4.c	2007-10-10 18:08:00.000000000 +0400
> > @@ -25,7 +25,7 @@ extern int sysctl_ip_nonlocal_bind;
> >  #ifdef CONFIG_SYSCTL
> >  static int zero;
> >  static int tcp_retr1_max = 255;
> > -static int ip_local_port_range_min[] = { 1, 1 };
> > +static int ip_local_port_range_min[] = { 1024, 1024 };
> >  static int ip_local_port_range_max[] = { 65535, 65535 };
> >  #endif
> >  
> > -
> 
> That only limits the sysctl, which seems completely counter productive.
> Sounds like more of the "stop root from shooting themselves" patches.

Agreed, we shouldn't be changing these values.

Re: [PATCH] do not give access to 1-1024 ports for autobinding

[David Miller]

From: "Denis V. Lunev" <den@openvz.org>
Date: Wed, 10 Oct 2007 18:34:49 +0400

> This patch prevents possibility to give 1-1024 port range for autobinding.
> {1, 1} may only takes some sense for deep embedded people.
> 
> Signed-off-by: Denis V. Lunev <den@openvz.org>

Administrators can configure their systems however they want,
the numbers are valid port numbers, so we should not prevent
the possibility.

Re: [PATCH] do not give access to 1-1024 ports for autobinding

[David Miller]

From: "Denis V. Lunev" <dlunev@gmail.com>
Date: Wed, 10 Oct 2007 20:59:13 +0400

> They have sense for the case of multiple network namespaces, where root
> in the other namespace can be treated as a user to initial namespace.

This is a silly limitation to impose just for the sake of
namespaces, please don't add it.