9b3b93c5e3
When spawning a thread via our virThread APIs we let pthread spawn this helper thread which sets couple of thread local variables (e.g. thread job name or thread worker name) and as of v6.1.0-40-gc85256b31b it also sets pthread name (which is then visible in `ps' output for instance). Only after these steps the intended function is called. However, just before calling it we free the buffer that holds the thread name which results in invalid memory reads: ==47027== Invalid read of size 1 ==47027== at 0x48389C2: strlen (vg_replace_strmem.c:459) ==47027== by 0x58BB3D6: __vfprintf_internal (vfprintf-internal.c:1645) ==47027== by 0x58CE6E0: __vasprintf_internal (vasprintf.c:57) ==47027== by 0x574BA28: g_vasprintf (in /usr/lib64/libglib-2.0.so.0.6000.7) ==47027== by 0x57240CC: g_strdup_vprintf (in /usr/lib64/libglib-2.0.so.0.6000.7) ==47027== by 0x48E0EFA: vir_g_strdup_vprintf (glibcompat.c:209) ==47027== by 0x493AA05: virLogVMessage (virlog.c:573) ==47027== by 0x493A8FE: virLogMessage (virlog.c:513) ==47027== by 0x4992FC7: virThreadJobClear (virthreadjob.c:121) ==47027== by 0x4992844: virThreadHelper (virthread.c:237) ==47027== by 0x5817496: start_thread (pthread_create.c:486) ==47027== by 0x59563CE: clone (clone.S:95) The problem is that neither virThreadJobSetWorker() nor virThreadJobSet() create a copy of passed name. They just set a thread local variable to point to the buffer which is then freed. Moving the free towards the end of the wrapper function solves the issue. Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@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, however, we mandate to have the build directory different than the source directory. For example, to build in a manner that is suitable for installing as root, use:
$ mkdir build && cd build
$ ../configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var
$ make
$ sudo make install
While to build & install as an unprivileged user
$ mkdir build && cd build
$ ../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: