Error reading TIFF image: "tiff directory length is too large"

[piponazo]

I have this error when trying to read an EXIF image I could perfectly read with the version 0.25:

$ ./exiv2 /tmp/tetracam_image.tif 
Exiv2 exception in print action for file /tmp/tetracam_image.tif:
tiff directory length is too large

I attach the image here so you can analyse the issue. This will block me to update the Exiv2 version in my software

[clanmills]

It's a multi-page tiff and Exiv2 does not support that. I don't think the error message is very helpful. There's an open issue to work on this. I created a script using some of libtiff utilities to cut the multipage tiff into single page files, modify the metadata and recombine them. Messy. Let me know if that "fix" is useful to you and I'll "point" you to the notes concerning this.

[piponazo]

But I still have a doubt. How is it possible that this piece of code:

Exiv2::Image::AutoPtr image = Exiv2::ImageFactory::open(fileName.toUtf8().constData());
image->readMetadata();

Was working on the version 0.25 and now in 0.26 it throws an exception in the readMetadata() function. Is it a new check introduced between 0.25 and 0.26 ?

[clanmills]

Yes. I added a two new Errors a few weeks ago. Error 55 and 56. Somebody was doing some “fuzzing” on our code and found ways to get us to crash.

I can’t remember if theres something different between v0.25 and v0.26 concerning this.

[clanmills]

I've remembered the change between v0.25 and v0.26 about this. image->readMetadata() in v0.26 calls image->printStructure(kpsRecursive) and that's where this "too big" thing is detected. In v0.25, I think we recover metadata and write some warnings to errout. In v0.26, we write more warnings to errout and recover the metadata. The current master throws these new errors.

We don't support multi-page tiff. We may have been recovering some metadata, however it's unlikely to be complete. Multi-page tiff is on the list for v0.27 http://dev.exiv2.org/news/3 However, I decided to do user support and mentoring for Exiv2 in 2017. If I do all the development and support, Exiv2 becomes a full-time job. More contributors are needed to work on this stuff.