[BUGFIX] Import/Export Various Exceptions happening

Fixed exception shown when

1) uploading an existing file without "Overwrite" setting activated
2) opening export module as a non-admin
3) opening import module as a non-admin without permission
   to access an available file storage

Also improved error message for missing default file upload folder.

Resolves: #72765
Releases: master
Change-Id: Id1133d1a8adc6c28088ef85730fe01145b4fa3a2
Reviewed-on: https://review.typo3.org/45998


Reviewed-by: Martin Kutschker <martin.kutschker@ymail.com>
Tested-by: Martin Kutschker <martin.kutschker@ymail.com>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>

typo3/sysext/impexp/Classes/Controller/ImportExportController.php

@@ -172,7 +172,9 @@ class ImportExportController extends BaseScriptClass
         $this->doc = GeneralUtility::makeInstance(DocumentTemplate::class);
         $this->doc->bodyTagId = 'imp-exp-mod';
         $this->pageinfo = BackendUtility::readPageAccess($this->id, $this->perms_clause);
-        $this->moduleTemplate->getDocHeaderComponent()->setMetaInformation($this->pageinfo);
+        if(is_array($this->pageinfo)) {
+            $this->moduleTemplate->getDocHeaderComponent()->setMetaInformation($this->pageinfo);
+        }
         // Setting up the context sensitive menu:
         $this->moduleTemplate->getPageRenderer()->loadRequireJsModule('TYPO3/CMS/Backend/ClickMenu');
         $this->moduleTemplate->getPageRenderer()->loadRequireJsModule('TYPO3/CMS/Impexp/ImportExport');
@@ -817,18 +819,24 @@ class ImportExportController extends BaseScriptClass
             $this->standaloneView->assign('inData', $inData);
             $this->standaloneView->assign('fileSelectOptions', $selectOptions);
 
-            $this->standaloneView->assign('importPath', sprintf($this->lang->getLL('importdata_fromPathS', true), $path ? $path->getCombinedIdentifier() : $this->lang->getLL('importdata_no_accessible_file_mount', true)));
+            if ($path) {
+                $this->standaloneView->assign('importPath', sprintf($this->lang->getLL('importdata_fromPathS', true), $path->getCombinedIdentifier()));
+            } else {
+                $this->standaloneView->assign('importPath', $this->lang->getLL('importdata_no_default_upload_folder', true));
+            }
             $this->standaloneView->assign('isAdmin', $beUser->isAdmin());
 
             // Upload file:
             $tempFolder = $this->getDefaultImportExportFolder();
-            $this->standaloneView->assign('tempFolder', $tempFolder->getCombinedIdentifier());
             if ($tempFolder) {
+                $this->standaloneView->assign('tempFolder', $tempFolder->getCombinedIdentifier());
                 $this->standaloneView->assign('hasTempUploadFolder', true);
                 if (GeneralUtility::_POST('_upload')) {
                     $this->standaloneView->assign('submitted', GeneralUtility::_POST('_upload'));
                     $this->standaloneView->assign('noFileUploaded', $this->fileProcessor->internalUploadMap[1]);
-                    $this->standaloneView->assign('uploadedFile', $this->uploadedFiles[0]->getName());
+                    if($this->uploadedFiles[0]) {
+                        $this->standaloneView->assign('uploadedFile', $this->uploadedFiles[0]->getName());
+                    }
                 }
             }
 

typo3/sysext/impexp/Resources/Private/Language/locallang.xlf

@@ -331,7 +331,10 @@
 				<source>Structure has been imported, here is the result:</source>
 			</trans-unit>
 			<trans-unit id="importdata_no_accessible_file_mount">
-				<source>No accessible file_mount</source>
+				<source>No accessible filemount</source>
+			</trans-unit>
+			<trans-unit id="importdata_no_default_upload_folder">
+				<source>No default upload folder</source>
 			</trans-unit>
 			<trans-unit id="filterpage_structureToBeImported">
 				<source>Structure to be imported:</source>