#vulnerable code 
                                @Override
    public AbstractFolderProperty<?> reconfigure(StaplerRequest req, JSONObject form) throws FormException {
        if (form == null) {
            return null;
        }

        // ignore modifications silently and return the unmodified object if the user
        // does not have the ADMINISTER Permission
        if (!userHasAdministerPermission()) {
            return this;
        }

        try {
            KubernetesFolderProperty newKubernetesFolderProperty = new KubernetesFolderProperty();

            Set<String> inheritedGrants = new HashSet<>();
            collectAllowedClouds(inheritedGrants, getOwner().getParent());

            JSONArray names = form.names();
            if (names != null) {
                for (Object name : names) {
                    String strName = (String) name;

                    if (strName.startsWith(PREFIX_USAGE_PERMISSION) && form.getBoolean(strName)) {
                        String cloud = StringUtils.replaceOnce(strName, PREFIX_USAGE_PERMISSION, "");

                        if (isUsageRestrictedKubernetesCloud(Jenkins.getInstance().getCloud(cloud))
                                && !inheritedGrants.contains(cloud)) {
                            newKubernetesFolderProperty.getPermittedClouds().add(cloud);
                        }
                    }
                }
            }

            return newKubernetesFolderProperty;
        } catch (JSONException jsonException) {
            LOGGER.severe(String.format("reconfigure failed: %s", jsonException.getMessage()));
            jsonException.printStackTrace();

            return this;
        }
    } 
                            #location 27 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                @Override
    public AbstractFolderProperty<?> reconfigure(StaplerRequest req, JSONObject form) throws FormException {
        if (form == null) {
            return null;
        }

        // ignore modifications silently and return the unmodified object if the user
        // does not have the ADMINISTER Permission
        if (!userHasAdministerPermission()) {
            return this;
        }

        try {
            Set<String> inheritedGrants = new HashSet<>();
            collectAllowedClouds(inheritedGrants, getOwner().getParent());

            Set<String> permittedClouds = new HashSet<>();
            JSONArray names = form.names();
            if (names != null) {
                for (Object name : names) {
                    String strName = (String) name;

                    if (strName.startsWith(PREFIX_USAGE_PERMISSION) && form.getBoolean(strName)) {
                        String cloud = StringUtils.replaceOnce(strName, PREFIX_USAGE_PERMISSION, "");

                        if (isUsageRestrictedKubernetesCloud(Jenkins.get().getCloud(cloud))
                                && !inheritedGrants.contains(cloud)) {
                            permittedClouds.add(cloud);
                        }
                    }
                }
            }
            this.permittedClouds.clear();
            this.permittedClouds.addAll(permittedClouds);
        } catch (JSONException e) {
            LOGGER.log(Level.SEVERE, e, () -> "reconfigure failed: " + e.getMessage());
        }
        return this;
    }