[Qemu-devel] [PULL for-2.0 7/7] virtio-rng: Avoid default_backend refcount leak

["Andreas Färber" <afaerber@suse.de>]

From: Stefan Hajnoczi <stefanha@redhat.com>

QOM child properties take a reference to the object and release it when
the property is deleted.  Therefore we should unref the default_backend
after we have added it as a child property.

Cc: KONRAD Frederic <fred.konrad@greensocs.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
---
 hw/virtio/virtio-rng.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/hw/virtio/virtio-rng.c b/hw/virtio/virtio-rng.c
index cbf0138..b6ab361 100644
--- a/hw/virtio/virtio-rng.c
+++ b/hw/virtio/virtio-rng.c
@@ -162,6 +162,9 @@ static void virtio_rng_device_realize(DeviceState *dev, Error **errp)
                                   OBJECT(vrng->conf.default_backend),
                                   NULL);
 
+        /* The child property took a reference, we can safely drop ours now */
+        object_unref(OBJECT(vrng->conf.default_backend));
+
         object_property_set_link(OBJECT(dev),
                                  OBJECT(vrng->conf.default_backend),
                                  "rng", NULL);
-- 
1.8.4.5