[gnome-settings-daemon] wacom: don't unref GdkDevices when we don't own a reference

[Carlos Garnacho <carlosg src gnome org>]

commit 8dcdeb7230633d62226f8b4786abc70fb99f6370
Author: Lubomir Rintel <lkundrak v3 sk>
Date:   Fri Mar 27 08:27:33 2015 +0100

    wacom: don't unref GdkDevices when we don't own a reference
    
    Commit 9e17dced137ff2fd05ed97c82e90a7725e9f82d7 added a bunch of unrefs
    which always unref the gdk_device after a g_object_get ("gdk-device").
    That is wrong -- getting a property doesn't increase a refcount.
    
    This causes the GdkDevices to be freed too early causing all sorts of
    crashes due to use-after-free() conditions:
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1194037
    https://bugzilla.gnome.org/show_bug.cgi?id=746866

 plugins/wacom/gsd-wacom-manager.c |    4 ----
 plugins/wacom/list-wacom.c        |    1 -
 2 files changed, 0 insertions(+), 5 deletions(-)
---
diff --git a/plugins/wacom/gsd-wacom-manager.c b/plugins/wacom/gsd-wacom-manager.c
index 9a293b9..c972620 100644
--- a/plugins/wacom/gsd-wacom-manager.c
+++ b/plugins/wacom/gsd-wacom-manager.c
@@ -480,7 +480,6 @@ set_keep_aspect (GsdWacomDevice *device,
        gsd_device = gsd_x11_device_manager_lookup_gdk_device (GSD_X11_DEVICE_MANAGER (device_manager),
                                                               gdk_device);
        monitor = gsd_device_mapper_get_device_monitor (mapper, gsd_device);
-       g_object_unref (gdk_device);
 
        /* Adjust area to match the monitor aspect ratio */
        g_debug ("Initial device area: (%d,%d) (%d,%d)", area[0], area[1], area[2], area[3]);
@@ -1343,7 +1342,6 @@ switch_monitor (GsdWacomManager *manager,
         g_object_get (device, "gdk-device", &gdk_device, NULL);
         gsd_device = gsd_x11_device_manager_lookup_gdk_device (GSD_X11_DEVICE_MANAGER 
(gsd_device_manager_get ()),
                                                                gdk_device);
-        g_object_unref (gdk_device);
         current_monitor =
                 gsd_device_mapper_get_device_monitor (manager->priv->device_mapper,
                                                       gsd_device);
@@ -1602,7 +1600,6 @@ check_need_for_calibration (GsdWacomDevice  *device)
         gsd_device = gsd_x11_device_manager_lookup_gdk_device (GSD_X11_DEVICE_MANAGER 
(gsd_device_manager_get ()),
                                                                gdk_device);
         monitor = gsd_device_mapper_get_device_monitor (mapper, gsd_device);
-        g_object_unref (gdk_device);
 
        if (monitor < 0) {
                geometry.width = gdk_screen_get_width (screen);
@@ -1967,7 +1964,6 @@ gsd_wacom_manager_stop (GsdWacomManager *manager)
                                 g_object_get (device, "gdk-device", &gdk_device, NULL);
                                 grab_button (gdk_x11_device_get_id (gdk_device),
                                              FALSE, manager->priv->screen);
-                                g_object_unref (gdk_device);
                         }
                 }
 
diff --git a/plugins/wacom/list-wacom.c b/plugins/wacom/list-wacom.c
index 4b15b9a..d91c679 100644
--- a/plugins/wacom/list-wacom.c
+++ b/plugins/wacom/list-wacom.c
@@ -196,7 +196,6 @@ get_edid (GsdWacomDevice *device)
 
        gsd_device = gsd_x11_device_manager_lookup_gdk_device (GSD_X11_DEVICE_MANAGER (gsd_device_manager_get 
()),
                                                               gdk_device);
-       g_object_unref (gdk_device);
        if (!gsd_device)
                goto bail;