From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Christophe Fergeau Date: Wed, 29 Jun 2016 16:57:36 +0200 Subject: [PATCH] usb-device-manager: Avoid USB event thread leak This is a follow-up of the previous commit ('usb-channel: Really stop listening for USB events on disconnection'). Since the USB event thread has to be stopped when we destroy the associated SpiceUsbDeviceManager, spice_usb_device_manager_dispose() should force event_thread_run to FALSE even if spice_usb_device_manager_stop_event_listening() was not enough. When this happens, this means that there is a bug in the internal users of spice_usb_device_manager_start_event_listening(), but with this change, we'll at least warn about it, and avoid a thread leak/potential future crash. --- src/usb-device-manager.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/src/usb-device-manager.c b/src/usb-device-manager.c index 808ec6c..53505fa 100644 --- a/src/usb-device-manager.c +++ b/src/usb-device-manager.c @@ -375,12 +375,22 @@ static void spice_usb_device_manager_dispose(GObject *gobject) #ifdef USE_LIBUSB_HOTPLUG if (priv->hp_handle) { spice_usb_device_manager_stop_event_listening(self); + if (g_atomic_int_get(&priv->event_thread_run)) { + /* Force termination of the event thread even if there were some + * mismatched spice_usb_device_manager_{start,stop}_event_listening + * calls. Otherwise, the usb event thread will be leaked, and will + * try to use the libusb context we destroy in finalize(), which would + * cause a crash */ + g_warn_if_reached(); + g_atomic_int_set(&priv->event_thread_run, FALSE); + } /* This also wakes up the libusb_handle_events() in the event_thread */ libusb_hotplug_deregister_callback(priv->context, priv->hp_handle); priv->hp_handle = 0; } #endif - if (priv->event_thread && !g_atomic_int_get(&priv->event_thread_run)) { + if (priv->event_thread) { + g_warn_if_fail(g_atomic_int_get(&priv->event_thread_run) == FALSE); g_thread_join(priv->event_thread); priv->event_thread = NULL; }