Re: [PATCH] xenstored: allow guests to reintroduce themselves

[Vincent Hanquez <vincent.hanquez@eu.citrix.com>]

On 08/09/2011 11:14 AM, Keir Fraser wrote:
> On 09/08/2011 11:08, "Vincent Hanquez"<vincent.hanquez@eu.citrix.com>
> wrote:
>
>>> xenstored: allow guests to reintroduce themselves
>>>
>>> During kexec all old watches have to be removed, otherwise the new
>>> kernel will receive unexpected events. Allow a guest to introduce itself
>>> and cleanup all of its watches.
>>
>> What about security wise ?
>>
>> Guest userspace suddenly becomes able to do this operation (and DoS themself)
>> where they used to be limited to normal read/write/.. operations.
>
> Guest userspace can already DoS the guest if it has access to xenstore, by
> messing with xenbus I/O connections, for example.

Re-reading i suspect you mean the xenbus devices here.
In that case, yes, you can probably do some damages here already.


-- 
Vincent