Reading binary data in paraview broken by libexpat1 update

[Carsten Gräser]

The recent update of libexpat1 to version 2.5.0-2ubuntu0.1 broke Paraview.
In particular reading vtu files containing binary data fails since this update. When trying to open files that worked fine before, Paraview now reports a parsing error like this one:

ERROR: In vtkXMLParser.cxx, line 376
vtkXMLDataParser (0x5b0ac36fc970): Error parsing XML in stream at line 21, column 0, byte index 1036: not well-formed (invalid token)

ERROR: In vtkXMLReader.cxx, line 521
vtkXMLUnstructuredGridReader (0x5b0ac3d3b670): Error parsing input file. ReadXMLInformation aborting.

The problem disappears when reverting libexpat1 to version 2.5.0-2.

[Carsten Gräser (graeser)]

This problem looks related and has been reported for arch: https://discourse.paraview.org/t/i-cannot-read-a-vtp-file-i-could-open-yesterday-can-someone-try-to-open-it/13938

[Carsten Gräser (graeser)]

Here's a corresponding bug report for debian sid: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1064762

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Peter Heywood (peethwd)]

On Jammy, the update from 2.4.7-1ubuntu0.2 to 2.4.7-1ubuntu0.3 causes simialr XML not well formed (invalid token) errors for files which contain binary data. Downgrading to 2.4.7-1 resolved the issue.

[Carsten Gräser (graeser)]

This also affects libdune-grid-dev by breaking the `subsamplingvtktest` test of the package. Steps to reproduce this locally:

1. Create a new dune module using `duneproject testvtk`, adding `dune-grid` as dependency.
2. Create subdirectory `dune/grid/io/file/test/` in `testvtk`
3. Copy the file `dune-grid/dune/grid/io/file/test/checkvtkfile.hh` from the dune-grid sources to `testvtk/dune/grid/io/file/test/`.
4. Overwrite file ´testvtk/src/testvtk.cc` by the test `dune-grid/dune/grid/io/file/test/subsamplingvtktest.cc` from the dune-grid sources.
5. Build the module using `dunecontrol all` and run `testvtk/build-cmake/src/testvtk`.

The same failure will probably show up when executing the tests while rebuilding the package `libdune-grid-dev`.

[Peter Heywood (peethwd)]

VTK has been patched upstream to correctly handle AppendedData elements in .vtu files with the updated/patched libexpat1:

https://gitlab.kitware.com/vtk/vtk/-/commit/db8f9efca220c9d16a30958e179abae3379d0011

https://gitlab.kitware.com/vtk/vtk/-/issues/19258

This will need backporting to older VTK releases on ubuntu's where libexpat1's fixes have been backported, which if I'm reading the ubuntu package release dates correctly is Jammy(security, updates), Mantic (security, updates) and potentially Noble (release).

[Fergus Cooper (fcooper8472)]

This still affects at least vtk9 (Ubuntu 24.04 and 22.04) and vtk7 (Ubuntu 22.04).

Is there any prospect of the VTK patch being applied and these packages updated?

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.