[FIX] Fortify Thumbnail Creation

Avoid errors because of missing files or division by zero.
papayaCMS · Nov 11, 2020 · dc73c71 · dc73c71
1 parent 8375b8d
commit dc73c71
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Showing 3 changed files with 36 additions and 11 deletions.
diff --git a/src/system/Papaya/Graphics/GD/GDLibrary.php b/src/system/Papaya/Graphics/GD/GDLibrary.php
@@ -88,13 +88,13 @@ public function load($fileName) {
      * @return int
      */
     public function identifyType($fileName) {
-      list(, , $type) = getimagesize($fileName);
-      return $type;
+      list(, , $type) = @getimagesize($fileName);
+      return $type ?: -1;
     }
 
     public function getImageSize($fileName) {
-      list($width, $height) = getimagesize($fileName);
-      return [$width, $height];
+      list($width, $height) = @getimagesize($fileName);
+      return [(int)$width, (int)$height];
     }
 
     /**

diff --git a/src/system/Papaya/Media/Thumbnail/Calculation/Contain.php b/src/system/Papaya/Media/Thumbnail/Calculation/Contain.php
@@ -48,15 +48,31 @@ public function getIdentifier() {
       return Calculation::MODE_FIX.'_'.$targetSize[0].'x'.$targetSize[1];
     }
 
-    private function getThumbnailSize() {
-      $factorX = $this->_width / $this->_maximumWidth;
-      $factorY = $this->_height / $this->_maximumHeight;
-      $thumbnailWidth = $this->_maximumWidth;
-      $thumbnailHeight = $this->_maximumHeight;
-      if ($factorX >= $factorY) {
+    private function getThumbnailSize()
+    {
+      if (
+        ($this->_width < 1 || $this->_height < 1) ||
+        ($this->_maximumWidth < 1 && $this->_maximumHeight < 1)
+      ) {
+        return [$this->_width, $this->_height];
+      } elseif ($this->_maximumHeight < 1) {
+        $factorX = $this->_width / $this->_maximumWidth;
+        $thumbnailWidth = $this->_maximumWidth;
         $thumbnailHeight = (int)round($this->_height / $factorX);
-      } else {
+      } elseif ($this->_maximumWidth < 1) {
+        $factorY = $this->_height / $this->_maximumHeight;
+        $thumbnailHeight = $this->_maximumHeight;
         $thumbnailWidth = (int)round($this->_width / $factorY);
+      } else {
+        $factorX = $this->_width / $this->_maximumWidth;
+        $factorY = $this->_height / $this->_maximumHeight;
+        $thumbnailWidth = $this->_maximumWidth;
+        $thumbnailHeight = $this->_maximumHeight;
+        if ($factorX >= $factorY) {
+          $thumbnailHeight = (int)round($this->_height / $factorX);
+        } else {
+          $thumbnailWidth = (int)round($this->_width / $factorY);
+        }
       }
       return [$thumbnailWidth, $thumbnailHeight];
     }

diff --git a/src/system/Papaya/Media/Thumbnails.php b/src/system/Papaya/Media/Thumbnails.php
@@ -98,6 +98,15 @@ public function createCalculation($targetWidth, $targetHeight, $mode = Calculati
     public function createThumbnail(Calculation $calculation, $mimeType = NULL, $useCache = TRUE) {
       $gd = $this->gd();
       $sourceFileName = $this->getSourceFileName();
+      if (!$this->fileSystem()->getFile($sourceFileName)->isReadable()) {
+        $this->logError(
+          Message::SEVERITY_ERROR,
+          sprintf(
+            'Can not create thumbnail, image file not found: %s', $sourceFileName
+          )
+        );
+        return NULL;
+      }
       if (NULL ===$mimeType) {
         $mimeType = $gd->identifyType($sourceFileName);
       }