6a2806fd54
If user has two domains, each have the same disk (configured for RW) but each runs with different seclabel then we deny start of the second domain because in order to do that we would need to relabel the disk but that would cut the first domain off. Even if we did not do that, qemu would fail to start because it would be unable to lock the disk image for the second time. So far, this behaviour is expected. But what is not expected is that we increase the refcounter in XATTRs and leave it like that. What happens is that when the second domain starts, virSecuritySetRememberedLabel() is called, and since there are XATTRs from the first domain it increments the refcounter and returns it (refcounter == 2 at this point). Then callers (virSecurityDACSetOwnership() and virSecuritySELinuxSetFileconHelper()) realize that refcounter is greater than 1 and desired seclabel doesn't match the one the disk image already has and an error is produced. But the refcounter is never decremented. Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1740024 Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
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 2.0 (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: