Commit b482925c added ptrace rule for the apparmor profiles, but one was missed in the libvirtd profile for dnsmasq. It was overlooked since the test machine did not have an active libvirt network requiring dnsmasq that was also set to autostart. With one active and set to autostart, the following denial is observed in audit.log when restarting libvirtd type=AVC msg=audit(1507320136.306:298): apparmor="DENIED" \ operation="ptrace" profile="/usr/sbin/libvirtd" pid=5472 \ comm="libvirtd" requested_mask="trace" denied_mask="trace" \ peer="/usr/sbin/dnsmasq" With an active network, I suspect a libvirtd restart causes access to /proc/<dnsmasq-pid>/*, hence the resulting denial. As a nasty side affect of the denial, libvirtd thinks it needs to spawn a dnsmasq process even though one is already running for the network. E.g. after two libvirtd restarts dnsmasq 1683 0.0 0.0 51188 2612 ? S 12:03 0:00 \ /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf \ --leasefile-ro --dhcp-script=/usr/lib64/libvirt/libvirt_leaseshelper root 1684 0.0 0.0 51160 576 ? S 12:03 0:00 \ /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf \ --leasefile-ro --dhcp-script=/usr/lib64/libvirt/libvirt_leaseshelper dnsmasq 4706 0.0 0.0 51188 2572 ? S 13:54 0:00 \ /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf \ --leasefile-ro --dhcp-script=/usr/lib64/libvirt/libvirt_leaseshelper root 4707 0.0 0.0 51160 572 ? S 13:54 0:00 \ /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf \ --leasefile-ro --dhcp-script=/usr/lib64/libvirt/libvirt_leaseshelper dnsmasq 4791 0.0 0.0 51188 2580 ? S 13:56 0:00 \ /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf \ --leasefile-ro --dhcp-script=/usr/lib64/libvirt/libvirt_leaseshelper root 4792 0.0 0.0 51160 572 ? S 13:56 0:00 \ /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf \ --leasefile-ro --dhcp-script=/usr/lib64/libvirt/libvirt_leaseshelper A simple fix is to add a ptrace rule for dnsmasq. Signed-off-by: Jim Fehlig <jfehlig@suse.com> Reviewed-By: Guido Günther <agx@sigxcpu.org>
Libvirt API for virtualization
Libvirt provides a portable, long term stable C API for managing the virtualization technologies provided by many operating systems. It includes support for QEMU, KVM, Xen, LXC, bhyve, Virtuozzo, VMware vCenter and ESX, VMware Desktop, Hyper-V, VirtualBox and the POWER Hypervisor.
For some of these hypervisors, it provides a stateful management daemon which runs on the virtualization host allowing access to the API both by non-privileged local users and remote users.
Layered packages provide bindings of the libvirt C API into other languages including Python, Perl, PHP, Go, Java, OCaml, as well as mappings into object systems such as GObject, CIM and SNMP.
Further information about the libvirt project can be found on the website:
License
The libvirt C API is distributed under the terms of GNU Lesser General
Public License, version 2.1 (or later). Some parts of the code that are
not part of the C library may have the more restrictive GNU General
Public License, version 2.1 (or later). See the files COPYING.LESSER
and COPYING
for full license terms & conditions.
Installation
Libvirt uses the GNU Autotools build system, so in general can be built and installed with the usual commands. For example, to build in a manner that is suitable for installing as root, use:
$ ./configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var
$ make
$ sudo make install
While to build & install as an unprivileged user
$ ./configure --prefix=$HOME/usr
$ make
$ make install
The libvirt code relies on a large number of 3rd party libraries. These will
be detected during execution of the configure
script and a summary printed
which lists any missing (optional) dependencies.
Contributing
The libvirt project welcomes contributions in many ways. For most components the best way to contribute is to send patches to the primary development mailing list. Further guidance on this can be found on the website:
https://libvirt.org/contribute.html
Contact
The libvirt project has two primary mailing lists:
- libvirt-users@redhat.com (for user discussions)
- libvir-list@redhat.com (for development only)
Further details on contacting the project are available on the website: