On Wed, 2016-12-07 at 08:37 +0100, Christian Ehrhardt wrote:
On Tue, Dec 6, 2016 at 5:40 PM, Jamie Strandboge
<jamie(a)canonical.com>
wrote:
>
> I forgot to reiterate: the above is true *unless* there is another
> non-DAC, non-
> MAC kernel mediation (eg, does the kernel only allow modifying the 'comm'
> value
> of its own threads? If so, then the rule would be safe to add to the
> default
> abstraction (though we should document that it is safe)).
>
Thanks for your help Jamie on thinking through the implications of this - I
really highly appreciate!
For the given interface the v2 should be safe see e.g.
http://man7.org/linux/man-pages/man5/proc.5.html
Quoting from there: "... A thread may modify *its* comm value, or that of
any of other thread *in the same thread group* ..."
Thanks for investigating this. +1 on adding this it the libvirt-qemu
abstraction:
# Per man(5) proc, the kernel enforces that a thread may
# only modify its comm value or those in its thread group.
owner @{PROC}/@{pid}/task/@{tid}/comm rw,
--
Jamie Strandboge |
http://www.canonical.com