Re: [libvirt] Potential segfault in udev driver
On Sun, Jan 24, 2010 at 11:07:59PM +0100, Matthias Bolte wrote:
udevDeviceMonitorStartup registers udevEventHandleCallback as event
handle, but doesn't store the returned watch id to remove it later on.
Also it's not clear to me whether the event handle should be register
for the whole lifetime of the udev driver instance or just for the
udevEnumerateDevices call.
The handler should be active for the lifetime of libvirtd, since the
udev driver has to detect hotplug/unplug events over time.
If for example the call to udevSetupSystemDev [1] fails
udevDeviceMonitorShutdown is called to cleanup, but
udevEventHandleCallback is still registered and may be called when
driverState is NULL again, resulting in a segfault in
udevEventHandleCallback.
So to solve this the udevEventHandleCallback event handle must be
removed at the appropriate place.
Yes, sounds like its needs to be removed in the failure path there
Daniel
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