Re: [PATCH v5 0/3] security: Yama LSM

Re: [PATCH v5 0/3] security: Yama LSM

[James Morris]

On Wed, 16 Mar 2011, John Johansen wrote:

> On 03/15/2011 06:35 PM, Kees Cook wrote:
> > On Tue, Mar 15, 2011 at 06:08:59PM -0700, Kees Cook wrote:
> >> This is an update of the Yama Linux Security Module.
> >>
> >> Now that there are attempts at permitting multiple active LSM modules,
> >> Yama should be reconsidered.
> > 
> Well not just that multiple active LSM modules are being reconsidered, but
> that YAMA is now being picked and used by a couple of other distros.

Distros should not be shipping out of tree code and then using that as a 
reason to ask for it to be merged.

We've obviously not reached a consensus on how to approach these security 
enhancements, so be aware that the final outcome upstream may not follow 
the approach that distros have already taken.

My preference is to see core security functionality incorporated into the 
core kernel where possible.

The purpose of LSM is to allow the configuration of different enhanced 
access control schemes (i.e. beyond Unix DAC).  Ad-hoc security 
enhancements which are not part of a coherent & distinct access control 
scheme should not be dropped into LSM simply because LSM has hooks in the 
right places, has security in the name, or because core developers pushed 
back on the code elsewhere.

Personally, I'd like to see the kernel offer as much hardening as possible 
for the general case, but this kind of work especially needs to be 
incorporated with full buy-in from core developers.



- James
-- 
James Morris
<jmorris@namei.org>

Re: [PATCH v5 0/3] security: Yama LSM

[John Johansen]

On 03/16/2011 05:52 PM, James Morris wrote:
> On Wed, 16 Mar 2011, John Johansen wrote:
> 
>> On 03/15/2011 06:35 PM, Kees Cook wrote:
>>> On Tue, Mar 15, 2011 at 06:08:59PM -0700, Kees Cook wrote:
>>>> This is an update of the Yama Linux Security Module.
>>>>
>>>> Now that there are attempts at permitting multiple active LSM modules,
>>>> Yama should be reconsidered.
>>>
>> Well not just that multiple active LSM modules are being reconsidered, but
>> that YAMA is now being picked and used by a couple of other distros.
> 
> Distros should not be shipping out of tree code and then using that as a 
> reason to ask for it to be merged.
> 
that wasn't actually my intent (though I will admit it kind of appears that
way), I was merely trying to say others are finding it useful.  That the YAMA
enhacements should be reconsidered, whether that be in the current form or
another.  I actually quite liked Casey's suggestion of splitting the controls

> We've obviously not reached a consensus on how to approach these security 
> enhancements, so be aware that the final outcome upstream may not follow 
> the approach that distros have already taken.
> 
true enough and distros who choose to ship something before upstream takes
it will have to deal with any breakage or incompatibilities.

> My preference is to see core security functionality incorporated into the 
> core kernel where possible.
> 
> The purpose of LSM is to allow the configuration of different enhanced 
> access control schemes (i.e. beyond Unix DAC).  Ad-hoc security 
> enhancements which are not part of a coherent & distinct access control 
> scheme should not be dropped into LSM simply because LSM has hooks in the 
> right places, has security in the name, or because core developers pushed 
> back on the code elsewhere.
>
Hrrmm, well I expect I have a slightly different take on this from both an
LSM and core dev pov.

> Personally, I'd like to see the kernel offer as much hardening as possible 
> for the general case, but this kind of work especially needs to be 
> incorporated with full buy-in from core developers.

Well I will agree that it needs to be hashed out again, and then maybe even
again and the best possible implementation needs to be settled on :)

I'm not arguing that YAMA needs to be taken in its current, just that it
implements features I would really like to see upstream.

Re: [PATCH v5 0/3] security: Yama LSM

[Thomas Gleixner]

On Thu, 17 Mar 2011, James Morris wrote:
> Personally, I'd like to see the kernel offer as much hardening as possible 
> for the general case, but this kind of work especially needs to be 
> incorporated with full buy-in from core developers.

And for that purpose it would be useful to see the actual
patches. Looks like they got submitted only to the obscurity
mailinglist.

Thanks,

	tglx