Clear static buffer returned by getpass()

src/stroke/stroke.c

@@ -129,6 +129,7 @@ static int send_stroke_msg(stroke_msg_t *msg)
 			if (pass)
 			{
 				stream->write_all(stream, pass, strlen(pass));
+				memwipe(pass, strlen(pass));
 				stream->write_all(stream, "\n", 1);
 			}
 		}