output: #fixed code
                                  @Override
      public synchronized Collection<NodeProvisioner.PlannedNode> provision(Label label, int excessWorkload) {
          try {
              LOGGER.log(Level.INFO, "Asked to provision {0} slave(s) for: {1}", new Object[]{excessWorkload,label});
  
              List<NodeProvisioner.PlannedNode> r = new ArrayList<NodeProvisioner.PlannedNode>();
  
              final List<DockerTemplate> templates = getTemplates(label);
  
              while (excessWorkload > 0 && !templates.isEmpty()) {
                  final DockerTemplate t = templates.get(0); // get first
  
                  LOGGER.log(Level.INFO, "Will provision \"{0}\" for: {1}", new Object[]{t.image,label});
  
                  try {
                      if (!addProvisionedSlave(t)) {
                          templates.remove(t);
                          continue;
                      }
                  } catch (Exception e) {
                      LOGGER.log(Level.WARNING, "Bad template {0}: {1}. Trying next template...",
                              new Object[]{t.image, e.getMessage()});
                      templates.remove(t);
                      continue;
                  }
  
                  r.add(new NodeProvisioner.PlannedNode(t.getDisplayName(),
                          Computer.threadPoolForRemoting.submit(new Callable<Node>() {
                              public Node call() throws Exception {
                                  // TODO: record the output somewhere
                                  DockerSlave slave = null;
                                  try {
                                      slave = t.provision(new StreamTaskListener(System.out));
                                      final Jenkins jenkins = Jenkins.getInstance();
                                      // TODO once the baseline is 1.592+ switch to Queue.withLock
                                      synchronized (jenkins.getQueue()) {
                                          jenkins.addNode(slave);
                                      }
                                      // Docker instances may have a long init script. If we declare
                                      // the provisioning complete by returning without the connect
                                      // operation, NodeProvisioner may decide that it still wants
                                      // one more instance, because it sees that (1) all the slaves
                                      // are offline (because it's still being launched) and
                                      // (2) there's no capacity provisioned yet.
                                      //
                                      // deferring the completion of provisioning until the launch
                                      // goes successful prevents this problem.
                                      slave.toComputer().connect(false).get();
                                      return slave;
                                  }
                                  catch(Exception ex) {
                                      LOGGER.log(Level.SEVERE, "Error in provisioning; slave=" + slave + ", template=" + t);
  
                                      ex.printStackTrace();
                                      throw Throwables.propagate(ex);
                                  }
                                  finally {
                                      decrementAmiSlaveProvision(t.image);
                                  }
                              }
                          })
                          ,t.getNumExecutors()));
  
                  excessWorkload -= t.getNumExecutors();
  
              }
              return r;
          } catch (Exception e) {
              LOGGER.log(Level.SEVERE,"Exception while provisioning for: " + label,e);
              return Collections.emptyList();
          }
      }
input: #vulnerable code 
                                  @Override
      public synchronized Collection<NodeProvisioner.PlannedNode> provision(Label label, int excessWorkload) {
          try {
  
              LOGGER.log(Level.INFO, "Asked to provision {0} slave(s) for: {1}", new Object[]{excessWorkload,label});
  
              List<NodeProvisioner.PlannedNode> r = new ArrayList<NodeProvisioner.PlannedNode>();
  
              final DockerTemplate t = getTemplate(label);
  
              LOGGER.log(Level.INFO, "Will provision \"{0}\" for: {1}", new Object[]{t.image,label});
  
              while (excessWorkload>0) {
  
                  if (!addProvisionedSlave(t.image, t.instanceCap)) {
                      break;
                  }
  
                  r.add(new NodeProvisioner.PlannedNode(t.getDisplayName(),
                          Computer.threadPoolForRemoting.submit(new Callable<Node>() {
                              public Node call() throws Exception {
                                  // TODO: record the output somewhere
                                  DockerSlave slave = null;
                                  try {
                                      slave = t.provision(new StreamTaskListener(System.out));
                                      final Jenkins jenkins = Jenkins.getInstance();
                                      // TODO once the baseline is 1.592+ switch to Queue.withLock
                                      synchronized (jenkins.getQueue()) {
                                          jenkins.addNode(slave);
                                      }
                                      // Docker instances may have a long init script. If we declare
                                      // the provisioning complete by returning without the connect
                                      // operation, NodeProvisioner may decide that it still wants
                                      // one more instance, because it sees that (1) all the slaves
                                      // are offline (because it's still being launched) and
                                      // (2) there's no capacity provisioned yet.
                                      //
                                      // deferring the completion of provisioning until the launch
                                      // goes successful prevents this problem.
                                      slave.toComputer().connect(false).get();
                                      return slave;
                                  }
                                  catch(Exception ex) {
                                      LOGGER.log(Level.SEVERE, "Error in provisioning; slave=" + slave + ", template=" + t);
  
                                      ex.printStackTrace();
                                      throw Throwables.propagate(ex);
                                  }
                                  finally {
                                      decrementAmiSlaveProvision(t.image);
                                  }
                              }
                          })
                          ,t.getNumExecutors()));
  
                  excessWorkload -= t.getNumExecutors();
  
              }
              return r;
          } catch (Exception e) {
              LOGGER.log(Level.SEVERE,"Exception while provisioning for: " + label,e);
              return Collections.emptyList();
          }
      } 
                              #location 11 
                              #vulnerability type NULL_DEREFERENCE