Commit 15160ab7 authored by Igor Mammedov's avatar Igor Mammedov Committed by Eduardo Habkost
Browse files

hostmem: fix crash when querying empty host-nodes property via QMP 



QEMU will crashes with
 qapi/qobject-output-visitor.c:210: qobject_output_complete: Assertion `qov->root && ((&qov->stack)->slh_first == ((void *)0))' failed
when trying to get value of not set hostmem's "host-nodes"
property, HostMemoryBackend::host_nodes bitmap doesn't have
any bits set in it, which leads to find_first_bit() returning
MAX_NODES and consequently to an early return from
host_memory_backend_get_host_nodes() without calling visitor.

Fix it by calling visitor even if "host-nodes" property wasn't
set before exiting from property getter to return valid empty
list.

Signed-off-by: default avatarIgor Mammedov <imammedo@redhat.com>
Message-Id: <20190214105733.25643-1-imammedo@redhat.com>
Reviewed-by: default avatarEric Blake <eblake@redhat.com>
Reviewed-by: default avatarStefano Garzarella <sgarzare@redhat.com>
Signed-off-by: default avatarEduardo Habkost <ehabkost@redhat.com>
parent 12b2e9f3

backends/hostmem.c

+2 −1
Original line number Diff line number Diff line
@@ -88,7 +88,7 @@ host_memory_backend_get_host_nodes(Object *obj, Visitor *v, const char *name, 


    value = find_first_bit(backend->host_nodes, MAX_NODES);

    if (value == MAX_NODES) {

        return;

        goto ret;

    }



    *node = g_malloc0(sizeof(**node));
@@ -106,6 +106,7 @@ host_memory_backend_get_host_nodes(Object *obj, Visitor *v, const char *name, 
        node = &(*node)->next;

    } while (true);



ret:

    visit_type_uint16List(v, name, &host_nodes, errp);

}