Re: [PATCH v2] nbd/server: Add --selinux-label option

[Eric Blake <eblake@redhat.com>]

On Fri, Jul 23, 2021 at 11:47:51AM +0100, Daniel P. Berrangé wrote:
> On Fri, Jul 23, 2021 at 11:33:03AM +0100, Richard W.M. Jones wrote:
> > Under SELinux, Unix domain sockets have two labels.  One is on the
> > disk and can be set with commands such as chcon(1).  There is a
> > different label stored in memory (called the process label).  This can
> > only be set by the process creating the socket.  When using SELinux +
> > SVirt and wanting qemu to be able to connect to a qemu-nbd instance,
> > you must set both labels correctly first.
> > 
> > For qemu-nbd the options to set the second label are awkward.  You can
> > create the socket in a wrapper program and then exec into qemu-nbd.
> > Or you could try something with LD_PRELOAD.
> > 
> > This commit adds the ability to set the label straightforwardly on the
> > command line, via the new --selinux-label flag.  (The name of the flag
> > is the same as the equivalent nbdkit option.)
> > 
> > A worked example showing how to use the new option can be found in
> > this bug: https://bugzilla.redhat.com/show_bug.cgi?id=1984938
> > 
> > Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1984938
> > Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
> > ---
> >  configure                                     |  9 ++++-
> >  meson.build                                   | 10 +++++-
> >  meson_options.txt                             |  3 ++
> >  qemu-nbd.c                                    | 33 +++++++++++++++++++
> >  tests/docker/dockerfiles/centos8.docker       |  1 +
> >  tests/docker/dockerfiles/fedora.docker        |  1 +
> >  tests/docker/dockerfiles/opensuse-leap.docker |  1 +
> >  tests/docker/dockerfiles/ubuntu1804.docker    |  1 +
> >  tests/docker/dockerfiles/ubuntu2004.docker    |  1 +
> >  9 files changed, 58 insertions(+), 2 deletions(-)
> 
> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

Thanks. This is a new feature, so it doesn't qualify for inclusion in
6.1, but I'm queuing it through my NBD tree to go in as soon as
upstream reopens for 6.2.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org