On Tue, 28 Feb 2023 13:29:18 -0800
Andrea Bolognani <abologna(a)redhat.com> wrote:
On Tue, Feb 28, 2023 at 07:53:09PM +0100, Stefano Brivio wrote:
> On Tue, 28 Feb 2023 10:06:18 -0800 Andrea Bolognani <abologna(a)redhat.com>
wrote:
> > On Tue, Feb 28, 2023 at 09:49:26AM -0500, Laine Stump wrote:
> > > + (NB: it is still necessary to disable SELinux to start passt.)
> >
> > This is also true for AppArmor, so I would mention both.
>
> Not in general -- thankfully, no pseudorandom label is forced by
> libvirt 9.1.0 with AppArmor (because there are no labels), and libvirtd
> simply runs passt unconfined (scrubbing the environment):
>
> $ grep "/usr/bin" src/security/apparmor/usr.sbin.libvirtd.in
> /usr/bin/* PUx,
>
> Then yes, with any recent version of Debian and openSUSE packages of
> passt, passt won't be able to create the socket or its PID file in the
> path libvirt asks for, because of the profile shipping with passt
> itself.
From the user's point of view, what is the difference between passt
not being able to start, or starting successfully but quitting
immediately afterwards because it can't create some files? I don't
think there's one. In both cases, you're going to see an error.
Yes yes, that's what I meant, there's no difference -- *but "just" with
Debian or openSUSE packages*, because they ship AppArmor profiles for
passt.
If you don't use packages, or, let's say, the Arch Linux package
(
https://aur.archlinux.org/packages/passt-git), this is not an issue,
no matter the LSM.
> Note that I'm *not* recommending to do this, just like
I'm not
> recommending to disable SELinux, and I don't think it's a good idea to
> suggest in release notes that users do this, either.
This is a limitation of the current implementation of passt support
in libvirt. We're actively working on removing it, but in the
meantime it should be documented somewhere. Are the release notes the
best place for that? Unclear. I don't think it's a particularly bad
one.
Me neither -- I actually suggested that if libvirt really needs to ship
a feature in this state, at least this should be added to the notes, so
that users don't think they're the ones doing something wrong, if
things don't work.
Anyone reading "you need to disable SELinux to use this
feature"
will surely infer that they shouldn't put it into production yet :)
I don't know, I guess you're most likely right, but I still see the
possible interpretation of a recommendation. At least as an argument in
the evaluation of vulnerability metrics. I'm really fine with either
Laine's version or your version, for what it's worth.
--
Stefano