Ticket #39552: functions.php.2.patch

wp-includes/functions.php

@@ -2366 +2366 @@
          */
         try {
                 if ( is_callable( 'exif_imagetype' ) ) {
-                        $mime = image_type_to_mime_type( exif_imagetype( $file ) );
+                        $imagetype = exif_imagetype( $file );
+                        // avoid falling back to application/octet-stream when exif_imagetype returns false
+                        if( $imagetype !== false ) {
+                                $mime = image_type_to_mime_type( $imagetype ); 
+                        } else {
+                                $mime = false;
+                        }
                 } elseif ( function_exists( 'getimagesize' ) ) {
                         $imagesize = getimagesize( $file );
                         $mime = ( isset( $imagesize['mime'] ) ) ? $imagesize['mime'] : false;
@@ -2373 +2379 @@
                 } else {
                         $mime = false;
                 }
+                 if( $mime === false && function_exists ( 'finfo_file' ) ){ 
+                        /* if the mime type is false we might have an image file not supported by PHP Constants (this applies 
+                         * at least to svg, but  might apply to other file types) To fix this, use finfo to determine the mimetype * instead 
+                         */ 
+                        $finfo = finfo_open( FILEINFO_MIME_TYPE ); 
+                        $mime = finfo_file( $finfo, $file ); 
+                        finfo_close( $finfo ); 
+                } 
         } catch ( Exception $e ) {
                 $mime = false;
         }