monitor: fix double-free of request error

qmp_error_response() will free the given error. Fix double-free in
later qmp_request_free().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180705164201.9853-1-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Fixes: 1cc37471525d03f963bc71d724f0dc9eab888fc1
Signed-off-by: Markus Armbruster <armbru@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/monitor.c b/monitor.c
index 3c9c97b73f..7af1f18d13 100644
--- a/monitor.c
+++ b/monitor.c
@@ -4186,6 +4186,7 @@ static void monitor_qmp_bh_dispatcher(void *data)
     } else {
         assert(req_obj->err);
         rsp = qmp_error_response(req_obj->err);
+        req_obj->err = NULL;
         monitor_qmp_respond(req_obj->mon, rsp, NULL);
         qobject_unref(rsp);
     }