On Tue, Dec 03, 2013 at 11:39:15AM +0100, Michal Privoznik wrote:
https://bugzilla.redhat.com/show_bug.cgi?id=1033061
Currently, initialization of drivers is done in a separate thread. This is done for several reasons: a driver that is initialized may require running event loop, it may take ages to initialize driver (e.g. due to autostarting domains). While the thread is spawn and run, the main() continues its execution. However, if something goes bad, or the event loop is just exited (e.g. due to a --timeout or SIGINT) we try to cleanup all the drivers. So we have two threads running Initialize() and Cleanup() concurrently. This may result in accessing stale pointers - e.g. netcf driver will free() itself in stateCleanup callback, while the init thread may come, open a dummy connection in order to autostart some domains and voilà: do_open() iterates over interface drivers and accesses stale netcf driver.
The fix consists in not running stateCleanup if the init thread is still running.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- daemon/libvirtd.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/daemon/libvirtd.c b/daemon/libvirtd.c index aef1546..49c42ad 100644 --- a/daemon/libvirtd.c +++ b/daemon/libvirtd.c @@ -108,6 +108,8 @@ virNetServerProgramPtr remoteProgram = NULL; virNetServerProgramPtr qemuProgram = NULL; virNetServerProgramPtr lxcProgram = NULL;
+volatile bool driversInitialized = false; + enum { VIR_DAEMON_ERR_NONE = 0, VIR_DAEMON_ERR_PIDFILE, @@ -912,6 +914,8 @@ static void daemonRunStateInit(void *opaque) goto cleanup; }
+ driversInitialized = true; + #ifdef HAVE_DBUS /* Tie the non-priviledged libvirtd to the session/shutdown lifecycle */ if (!virNetServerIsPrivileged(srv)) { @@ -1546,7 +1550,8 @@ cleanup:
daemonConfigFree(config);
- virStateCleanup(); + if (driversInitialized) + virStateCleanup();
Don't we technically need to use an int and atomic int APIs for these changes ? Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|