JpegMetadataExtractor: Don't fail when garbage bytes are present between JPEG sections

In theory JPEG files are not allowed to contain anything between the sections,
but in practice they sometimes do. It's customary to ignore the garbage data.

Bug: T148606
Change-Id: I98f2609644bcd8bfd7c1679afc6e7af83e228685

diff --git a/includes/media/JpegMetadataExtractor.php b/includes/media/JpegMetadataExtractor.php
index 9ad4097..67c957a 100644 (file)
--- a/includes/media/JpegMetadataExtractor.php
+++ b/includes/media/JpegMetadataExtractor.php
@@ -82,9 +82,10 @@ class JpegMetadataExtractor {
                                // this is just a sanity check
                                throw new MWException( 'Too many jpeg segments. Aborting' );
                        }
                                // this is just a sanity check
                                throw new MWException( 'Too many jpeg segments. Aborting' );
                        }

-                       if ( $buffer !== "\xFF" ) {
-                               throw new MWException( "Error reading jpeg file marker. " .
-                                       "Expected 0xFF but got " . bin2hex( $buffer ) );
+                       while ( $buffer !== "\xFF" ) {
+                               // In theory JPEG files are not allowed to contain anything between the sections,
+                               // but in practice they sometimes do. It's customary to ignore the garbage data.
+                               $buffer = fread( $fh, 1 );

                        }
 
                        $buffer = fread( $fh, 1 );
                        }
 
                        $buffer = fread( $fh, 1 );