output: #fixed code
                                  private Node getNodeByName(String name, StaplerResponse rsp) throws IOException {
          Jenkins jenkins = Jenkins.get();
  
          try {
              Node n = jenkins.getNode(name);
  
              if (n == null) {
                  rsp.setStatus(SC_NOT_FOUND);
                  rsp.setContentType("text/plain; UTF-8");
                  rsp.getWriter().printf("A slave called '%s' does not exist.%n", name);
                  return null;
              }
              return n;
          } catch (NullPointerException ignored) {}
  
          return null;
      }
input: #vulnerable code 
                                  private Node getNodeByName(String name, StaplerResponse rsp) throws IOException {
          Jenkins jenkins = Jenkins.getInstance();
  
          try {
              Node n = jenkins.getNode(name);
  
              if (n == null) {
                  rsp.setStatus(SC_NOT_FOUND);
                  rsp.setContentType("text/plain; UTF-8");
                  rsp.getWriter().printf("A slave called '%s' does not exist.%n", name);
                  return null;
              }
              return n;
          } catch (NullPointerException ignored) {}
  
          return null;
      } 
                              #location 5 
                              #vulnerability type NULL_DEREFERENCE