Strip out Traceback from HTTP response

We should not let stack traces leak to the REST API users

Fixes LP# 1103324
Fixes LP# 1092610

Change-Id: Ic1208bfeb7d44e672f8b8d3a4004a9802c14e7b9

nova/api/openstack/wsgi.py

@@ -1182,10 +1182,18 @@ def __call__(self, req):
         # Replace the body with fault details.
         code = self.wrapped_exc.status_int
         fault_name = self._fault_names.get(code, "computeFault")
+        explanation = self.wrapped_exc.explanation
+        offset = explanation.find("Traceback")
+        if offset is not -1:
+            LOG.debug(_("API request failed, fault raised to the top of"
+                      " the stack. Detailed stacktrace %s") %
+                      explanation)
+            explanation = explanation[0:offset - 1]
+
         fault_data = {
             fault_name: {
                 'code': code,
-                'message': self.wrapped_exc.explanation}}
+                'message': explanation}}
         if code == 413:
             retry = self.wrapped_exc.headers.get('Retry-After', None)
             if retry: