WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] Module loading in unpriveledged domains

To: david.nospam.hopwood@xxxxxxxxxxxxxxxx
Subject: Re: [Xen-devel] Module loading in unpriveledged domains
From: Ian Pratt <Ian.Pratt@xxxxxxxxxxxx>
Date: Mon, 22 Nov 2004 21:57:03 +0000
Cc: xen-devel@xxxxxxxxxxxxxxxxxxxxx, Ian.Pratt@xxxxxxxxxxxx
Delivery-date: Mon, 22 Nov 2004 21:59:24 +0000
Envelope-to: xen+James.Bulpin@xxxxxxxxxxxx
In-reply-to: Your message of "Mon, 22 Nov 2004 19:37:56 GMT." <41A24014.9060400@xxxxxxxxxxxxxxxx>
List-archive: <http://sourceforge.net/mailarchive/forum.php?forum=xen-devel>
List-help: <mailto:xen-devel-request@lists.sourceforge.net?subject=help>
List-id: List for Xen developers <xen-devel.lists.sourceforge.net>
List-post: <mailto:xen-devel@lists.sourceforge.net>
List-subscribe: <https://lists.sourceforge.net/lists/listinfo/xen-devel>, <mailto:xen-devel-request@lists.sourceforge.net?subject=subscribe>
List-unsubscribe: <https://lists.sourceforge.net/lists/listinfo/xen-devel>, <mailto:xen-devel-request@lists.sourceforge.net?subject=unsubscribe>
Sender: xen-devel-admin@xxxxxxxxxxxxxxxxxxxxx
> Ian Pratt wrote:
> >>Is there any security risk in enabling loadable module support in the linux
> >>kernel used for the unpriveledged domains? I ask this question in the 
> >>context of
> >>a virtual private server hosting provider.
> > 
> > There shouldn't be any security risk at all -- Xen should provide
> > all the isolation you need (modulo any bugs).
> 
> So the answer to the original question is, "yes, enabling loadable module
> support will increase your exposure to security risks due to any weaknesses
> in Xen's isolation." Xen hasn't had particularly extensive security review
> yet.

I don't think that preventing loadable module support is going to
buy you anything. If your users have root they can write to the
domain's memory image and hence in practice do anything that they
could if they had kernel modules.

Xen has been designed to provide secure isolation between
guests. It has undergone code review by a bunch of different
people. It may have security bugs, but at least they're
relatively obscure...

Ian


-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.sourceforge.net/lists/listinfo/xen-devel