qmp: Fix device-list-properties not to crash for abstract device

Broken in commit f4eb32b "qmp: show QOM properties in
device-list-properties", v2.1.

Cc: qemu-stable@nongnu.org
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Message-Id: <1443689999-12182-9-git-send-email-armbru@redhat.com>
(cherry picked from commit edb1523d90415cb79f60f83b4028ef3820d15612)

Conflicts:
	tests/device-introspect-test.c

* removed hunk specific to QAPI introspection (not in 2.4)

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/qmp.c b/qmp.c
index 403805a551..8603c46bdb 100644
--- a/qmp.c
+++ b/qmp.c
@@ -514,6 +514,12 @@ DevicePropertyInfoList *qmp_device_list_properties(const char *typename,
         return NULL;
     }
 
+    if (object_class_is_abstract(klass)) {
+        error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "name",
+                   "non-abstract device type");
+        return NULL;
+    }
+
     obj = object_new(typename);
 
     QTAILQ_FOREACH(prop, &obj->properties, node) {