50c7a27244
In recent commit of bf8bd93df0 (and friends) we switched the way
we process queried command line arguments: from string lists to
virJSONValue stored in a hash table. To achieve this
qemuMonitorJSONGetCommandLineOptions() helper was introduced
which executes the "query-command-line-options" monitor command
and then calls virJSONValueArrayForeachSteal() to process the
output. The array process function is also given
qemuMonitorJSONGetCommandLineOptionsWorker() as the callback
which is called over each item of the returned array. This
callback then steals "parameters" attribute of each array iteam
storing it in the hash table, but it leaves behind "option"
attribute (because it's g_strdup()-ed). After all of this, the
callback returns 0 which is a signal to the array processing
function that the callback took ownership of the array item. But
this is not true. While it removed "parameters" it did not take
the rest ("option" for instance). And therefore, it leads to a
memory leak:
5,347 (1,656 direct, 3,691 indirect) bytes in 69 blocks are definitely lost in loss record 2,752 of 2,794
at 0x483BEC5: calloc (vg_replace_malloc.c:760)
by 0x4E25A10: g_malloc0 (in /usr/lib64/libglib-2.0.so.0.6400.5)
by 0x4943317: virJSONValueNewObject (virjson.c:569)
by 0x4945692: virJSONParserHandleStartMap (virjson.c:1768)
by 0x5825A86: yajl_do_parse (in /usr/lib64/libyajl.so.2.1.0)
by 0x4945BFA: virJSONValueFromString (virjson.c:1896)
by 0xAF5C115: qemuMonitorJSONIOProcessLine (qemu_monitor_json.c:224)
by 0xAF5C45E: qemuMonitorJSONIOProcess (qemu_monitor_json.c:279)
by 0xAF4BB6C: qemuMonitorIOProcess (qemu_monitor.c:342)
by 0xAF4C444: qemuMonitorIO (qemu_monitor.c:574)
by 0x4FEF846: socket_source_dispatch (in /usr/lib64/libgio-2.0.so.0.6400.5)
by 0x4E1F727: g_main_context_dispatch (in /usr/lib64/libglib-2.0.so.0.6400.5)
The callback must return 1 so that the array item is properly
freed.
Fixes: ebeff6cd57d07c89d42e191ed0085a9dd89835c5
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@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
Instructions on building and installing libvirt can be found on the website:
https://libvirt.org/compiling.html
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: