qdev: Add cleanup logic in device_set_realized() to avoid resource leak

At present, this function doesn't have partial cleanup implemented,
which will cause resource leaks in some scenarios.

Example:

1. Assume that "dc->realize(dev, &local_err)" executes successful
   and local_err == NULL;
2. device hotplug in hotplug_handler_plug() executes but fails
   (it is prone to occur). Then local_err != NULL;
3. error_propagate(errp, local_err) and return. But the resources
   which have been allocated in dc->realize() will be leaked.
Simple backtrace:
  dc->realize()
   |->device_realize
            |->pci_qdev_init()
                |->do_pci_register_device()
                |->etc.

Add fuller cleanup logic which assures that function can
goto appropriate error label as local_err population is
detected at each relevant point.

Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Andreas Färber <afaerber@suse.de>
This commit is contained in:
Gonglei 2014-09-04 10:18:26 +08:00 committed by Andreas Färber
parent cd4520adca
commit 1d45a705fc

View File

@ -834,12 +834,14 @@ static void device_set_realized(Object *obj, bool value, Error **errp)
dc->realize(dev, &local_err);
}
if (dev->parent_bus && dev->parent_bus->hotplug_handler &&
local_err == NULL) {
if (local_err != NULL) {
goto fail;
}
if (dev->parent_bus && dev->parent_bus->hotplug_handler) {
hotplug_handler_plug(dev->parent_bus->hotplug_handler,
dev, &local_err);
} else if (local_err == NULL &&
object_dynamic_cast(qdev_get_machine(), TYPE_MACHINE)) {
} else if (object_dynamic_cast(qdev_get_machine(), TYPE_MACHINE)) {
HotplugHandler *hotplug_ctrl;
MachineState *machine = MACHINE(qdev_get_machine());
MachineClass *mc = MACHINE_GET_CLASS(machine);
@ -852,21 +854,24 @@ static void device_set_realized(Object *obj, bool value, Error **errp)
}
}
if (qdev_get_vmsd(dev) && local_err == NULL) {
if (local_err != NULL) {
goto post_realize_fail;
}
if (qdev_get_vmsd(dev)) {
vmstate_register_with_alias_id(dev, -1, qdev_get_vmsd(dev), dev,
dev->instance_id_alias,
dev->alias_required_for_version);
}
if (local_err == NULL) {
QLIST_FOREACH(bus, &dev->child_bus, sibling) {
object_property_set_bool(OBJECT(bus), true, "realized",
QLIST_FOREACH(bus, &dev->child_bus, sibling) {
object_property_set_bool(OBJECT(bus), true, "realized",
&local_err);
if (local_err != NULL) {
break;
}
if (local_err != NULL) {
goto child_realize_fail;
}
}
if (dev->hotplugged && local_err == NULL) {
if (dev->hotplugged) {
device_reset(dev);
}
dev->pending_deleted_event = false;
@ -888,11 +893,30 @@ static void device_set_realized(Object *obj, bool value, Error **errp)
}
if (local_err != NULL) {
error_propagate(errp, local_err);
return;
goto fail;
}
dev->realized = value;
return;
child_realize_fail:
QLIST_FOREACH(bus, &dev->child_bus, sibling) {
object_property_set_bool(OBJECT(bus), false, "realized",
NULL);
}
if (qdev_get_vmsd(dev)) {
vmstate_unregister(dev, qdev_get_vmsd(dev), dev);
}
post_realize_fail:
if (dc->unrealize) {
dc->unrealize(dev, NULL);
}
fail:
error_propagate(errp, local_err);
return;
}
static bool device_get_hotpluggable(Object *obj, Error **errp)