Re: [Qemu-devel] [PULL v4 00/38] Test and build patches

[Fam Zheng <famz@redhat.com>]

On Fri, 09/15 12:40, Daniel P. Berrange wrote:
> On Fri, Sep 15, 2017 at 11:55:44AM +0100, Peter Maydell wrote:
> > On 15 September 2017 at 10:02, Fam Zheng <famz@redhat.com> wrote:
> > > The following changes since commit 04ef33052c205170c92df21ca0b4be4f3b102188:
> > >
> > >   tcg/tci: do not use ldst label (never implemented) (2017-09-11 19:24:05 +0100)
> > >
> > > are available in the git repository at:
> > >
> > >   git://github.com/famz/qemu.git tags/test-and-build-pull-request
> > >
> > > for you to fetch changes up to be78fe670401af14e6d63fce5c5467f751207871:
> > >
> > >   buildsys: Move rdma libs to per object (2017-09-15 15:05:24 +0800)
> > >
> > > ----------------------------------------------------------------
> > >
> > > ----------------------------------------------------------------
> > >
> > > Alex Bennée (4):
> > >   docker: ensure NOUSER for travis images
> > >   docker: docker.py make --no-cache skip checksum test
> > >   docker: don't install device-tree-compiler build-deps in travis.docker
> > >   docker: reduce noise when building travis.docker
> > >
> > > Fam Zheng (34):
> > >   docker: Update ubuntu image
> > >   docker: Enable features explicitly in test-full
> > >   tests/docker: Clean up paths
> > >   gitignore: Ignore vm test images
> > >   qemu.py: Add "wait()" method
> > >   scripts: Add archive-source.sh
> > >   tests: Add a test key pair
> > 
> > So, before I commit an ssh private key to our git repo,
> > can you explain why it's ok that this is public? The
> > commit message for the relevant patch doesn't really say.
> 
> IIUC, the public part of the key gets exposed to the guest images via
> cloud-init metadata. During boot the guest read this metadata and add
> the public key to authorized_keys. The private key is used by the test
> suite on the host so that it can now login to the guests.
> 
> So the risk here is that if these guests were exposed to the LAN in any
> way, someone could grab our private key and login to these guests.
> 
> What saves us is that the VMs are run with user mode slirp networking
> so AFAICT, aren't exposed to the LAN.  So as long as we don't change
> this to any kind of real networking, I think its acceptable to have
> the private key in it and doesn't expose developer's workstations to
> undue risk and avoids consuming system entropy to generate new keys
> during build.

The hostfwd does listen on a dynamic port on 0.0.0.0, so does vnc. I didn't
really care since it's for temporary guests and for me convenience outweighed a
bit.  The VM test is indeed less restricted than the docker ones such as in that
network is always available. Should it be a problem?

We can probably add restrict=on to slirp and listen on loopback.

Fam