Re: SELinux labels change in libvirt

On Tue, Jul 14, 2020 at 03:21:17PM +0300, Ram Lavi wrote: > Hello all, > > tl;dr, can you point me to the point in the libvirt repo where it's trying > to change a tap-device's SELinux label? > > I am trying to create a tap device with libvirt on a > super-privileged container, and then use it on another, > unprivileged container with libvirt. > User wise, I know I need the super-privileged container to open the tap > device with the user of the unprivileged one - that I already did and it's > not the issue. > But I have a problem when I open the tap device in the > non-privileged container: the tap device currently has the spc_t label > since the tun_socket inherited the selinux context from the > super-privileged container who creates it. then libvirt is trying to change > the SELinux labels, and since it's not privileged then it fails. > But I didn't find where and how libvirt is trying to change the tap > device's label. > > Can you point me to that specific code on libvirt? If the SELinux policy that libvirtd is running under prevents it from re-labelling, then TAP devices label failure is just going to be one out of 100's of labelling failures.

Either the SELinux policy needs to be changed to allow libvirtd to relabel stuff in the normal manner, or you will have to turn off SELinux support in libvirtd. in /etc/libvirt/qemu.conf via the param security_driver = "none". If you turn off SELinux in libvirt, then you no longer have separation of QEMU processes which may be a security flaw depending on your deplyoment scenario.

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 :|