From: "Daniel P. Berrangé" <berrange@redhat.com>
To: Kevin Wolf <kwolf@redhat.com>
Cc: vsementsov@virtuozzo.com, eblake@redhat.com,
"Richard W.M. Jones" <rjones@redhat.com>,
qemu-block@nongnu.org, qemu-devel@nongnu.org
Subject: Re: [PATCH v2] nbd/server: Add --selinux-label option
Date: Fri, 23 Jul 2021 17:38:06 +0100 [thread overview]
Message-ID: <YPrwbgY9Q4e1ORP1@redhat.com> (raw)
In-Reply-To: <YPrr72N494WKnJA5@redhat.com>
On Fri, Jul 23, 2021 at 06:18:55PM +0200, Kevin Wolf wrote:
> Am 23.07.2021 um 12:33 hat Richard W.M. Jones geschrieben:
> > 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>
>
> I suppose this would also be relevant for the built-in NBD server,
> especially in the context of qemu-storage-daemon?
It depends on the usage scenario really. nbdkit / qemu-nbd are
not commonly run under any SELinux policy, so then end up being
unconfined_t. A QEMU NBD client can't connect to an unconfined_t
socket, so we need to override it with this arg.
In the case of qemu system emulator, under libvirt, it will
already have a svirt_t type, so in that case there is no need
to override the type for the socket.
For qsd there's not really any strong practice established
but i expect most current usage is unconfined_t too and
would benefit from setting label.
> If so, is this something specific to NBD sockets, or would it actually
> make sense to have it as a generic option in UnixSocketAddress?
It is applicable to inet sockets too in fact.
Regards,
Daniel
--
|: https://berrange.com -o- https://www.flickr.com/photos/dberrange :|
|: https://libvirt.org -o- https://fstop138.berrange.com :|
|: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
next prev parent reply other threads:[~2021-07-23 17:05 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-23 10:33 [PATCH v2] nbd/server: Add --selinux-label option Richard W.M. Jones
2021-07-23 10:33 ` Richard W.M. Jones
2021-07-23 10:47 ` Daniel P. Berrangé
2021-07-26 14:22 ` Eric Blake
2021-07-23 16:18 ` Kevin Wolf
2021-07-23 16:34 ` Richard W.M. Jones
2021-07-23 16:38 ` Daniel P. Berrangé [this message]
2021-08-25 19:35 ` Eric Blake
2021-09-24 19:23 ` Eric Blake
2021-09-27 12:48 ` Vladimir Sementsov-Ogievskiy
2021-09-27 12:55 ` Daniel P. Berrangé
2021-09-27 21:18 ` Eric Blake
2021-09-27 21:39 ` Richard W.M. Jones
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YPrwbgY9Q4e1ORP1@redhat.com \
--to=berrange@redhat.com \
--cc=eblake@redhat.com \
--cc=kwolf@redhat.com \
--cc=qemu-block@nongnu.org \
--cc=qemu-devel@nongnu.org \
--cc=rjones@redhat.com \
--cc=vsementsov@virtuozzo.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).