Exiftool hanging

[llazon]

Hi Phil, I came across an image, looks like from an older Nokia phone that is causing Exiftool to hang.  Through my amateur debugging with Perl, looks like it gets stuck in a loop reading tags.

Code Select Expand

Image::ExifTool::SetupTagTable(/usr/share/perl5/Image/ExifTool.pm:5801):
5801:         foreach $tagInfo (@infoArray) {

As I don't have permission to share publicly, I will send this image via email.

Originally found with Exiftool 13.18, but verified it is an issue with 13.22 as well.  On Linux and Mac.

Thanks!

Lee

[Phil Harvey]

Hi Lee,

Thanks for this report but I am not able to reproduce the issue.  The command "exiftool FILE" works normally on this file for version 13.18, 13.22 and the current version of ExifTool.  This is on MacOS so it should be the same as you.

What is the output of "exiftool -v -ver" on your system?  My worry is that this could be a Perl bug.  I'm running Perl 5.018004.

There are a number of issues with the metadata in this image, including improperly written XMP, but nothing I can see that should cause  a hang.  However, there is a large extended XMP that could potentially cause issues if the memory isn't handled properly.

But the code you mention isn't reading tags from the file -- it is setting up the standard pre-defined tags in the internal tables.

- Phil

Edit:  I am able to reproduce this issue using Perl 5.026003.  -- I'll let you know when I find a solution.

[Phil Harvey]

Looking more closely, the XMP is badly corrupted past a certain point, which is triggering a Perl bug when parsing this data.

I have implemented a patch to avoid this hang, and ExifTool 13.23 shouldn't exhibit this problem.

Thanks again for this report.

- Phil

[llazon]

Awesome, we always appreciate your time and quick responses! 

Just for reference, on my Mac I am running Perl v5.34.1.  On Linux v5.34.0.

I'll keep an eye out for ExifTool 13.23.

Thanks again!

Lee

[Phil Harvey]

Just for reference, I've experience bugs like this in other versions of Perl.  The problem occurs if you have a capture in a regex expression that captures something too large.  In this case the corrupted XMP was about 5MB and the capture size could have been around a MB or so.  I blame Adobe for pioneering the nonsensical strategy of putting image data in XMP, which is why the XMP was so large in the first place.

- Phil

[Phil Harvey]

Version 13.23 is now available.

- Phil