Division by zero during Pulp import

[dralley]

Version
3.36.0+

Describe the bug

During a Katello test run, the following exception was encountered

 {"traceback"=>"  File \"/usr/lib/python3.11/site-packages/pulpcore/tasking/tasks.py\", line 61, in _execute_task\n    result = func(*args, **kwargs)\n             ^^^^^^^^^^^^^^^^^^^^^\n  File \"/usr/lib/python3.11/site-packages/pulpcore/app/tasks/importer.py\", line 453, in pulp_import\n    with tarfile.open(path, \"r\", fileobj=fp) as tar:\n         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n  File \"/usr/lib64/python3.11/tarfile.py\", line 1815, in open\n    fileobj.seek(saved_pos)\n  File \"/usr/lib/python3.11/site-packages/pulpcore/app/tasks/importer.py\", line 132, in seek\n    self.chunk = target // self.chunk_size\n                 ~~~~~~~^^~~~~~~~~~~~~~~~~\n", "description"=>"integer division or modulo by zero"} (Katello::Errors::Pulp3Error)

I'm not 100% certain, but I suspect the cause here is that if chunks aren't used during the export, chunk_size is set to 0:

https://github.com/pulp/pulpcore/blob/main/pulpcore/app/tasks/export.py#L456C31-L456C31

and ChunkedFile reads that value here:

https://github.com/pulp/pulpcore/blob/main/pulpcore/app/tasks/importer.py#L79

and we're using ChunkedFile even in the non-chunked case so long as a TOC file was provided.

https://github.com/pulp/pulpcore/blob/main/pulpcore/app/tasks/importer.py#L335-L336

To Reproduce

I would expect it to be reproducible if performing a non-chunked export, and providing a TOC path for the import.

Expected behavior

We should never see an integer division by zero error.

Additional context

[dralley]

We'll also want to expand our tests to cover this

[mdellweg]

Does this mean that we can provide a toc file that makes a non-chunked import look like one with a single chunk, only the specified chunk-size is wrong?

[tannermsmith1]

Thank you for working to address this! We started seeing this on our team about 3 weeks ago on our Pulp 3 servers. We haven't been able to import content to an air-gapped Pulp 3 server since upgrading past 3.36.0. We export the content non-chunked.

[pulpbot]

https://bugzilla.redhat.com/show_bug.cgi?id=2253673