Re: [libvirt] [PATCH] lxc: stop rootless containers from messing with system mounts

["Daniel P. Berrange" <berrange redhat com>]

On Mon, Apr 06, 2009 at 01:47:42PM -0500, Serge E. Hallyn wrote:
> If a container has no root, liblxc remounts /proc.  If the
> system had marked / as MS_SHARED, then even though the
> container is in a new mounts namespace, the mount event is
> propagated back to the host mounts namespace, overwriting
> /proc.  After that, for instance, ps will no longer show
> system processes.
> 
> A Fedora 11 default install has / MS_SHARED.
> 
> Make sure that root is not MS_SHARED before remounting
> /proc.  I'm making it MS_SLAVE so that the container
> will receive mount events from the host, but not vice
> versa.
> 
> Signed-off-by: Serge Hallyn <serue us ibm com>

Doh, that's rather annoying. ACK to this patch. 

Daniel
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