[SECURITY] update in ipynb2md.py

[DanMcInerney]

Fixed command injection bug where a user could payload the Jupyter notebook name or md filename with something like "notebook.ipynb&&cat /etc/shadow>/public_html/index.html".

Description

(Brief description on what this PR is about)

Checklist

Essentials

• PR's title starts with a category (e.g. [BUGFIX], [MODEL], [TUTORIAL], [FEATURE], [DOC], etc)
• Changes are complete (i.e. I finished coding on this PR)
• All changes have test coverage
• Code is well-documented

Changes

• Changes direct argument injection in a system command to a safely escaped one in case webserver ever gives access to this script

Comments

• If this change is a backward incompatible change, why must this change be made.
• Interesting edge cases to note here

[mxnet-bot]

Hey @DanMcInerney , Thanks for submitting the PR
All tests are already queued to run once. If tests fail, you can trigger one or more tests again with the following commands:

• To trigger all jobs: @mxnet-bot run ci [all]
• To trigger specific jobs: @mxnet-bot run ci [job1, job2]

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CI supported jobs: [sanity, miscellaneous, clang, unix-cpu, website, centos-gpu, centos-cpu, edge, windows-gpu, windows-cpu, unix-gpu]

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Note:
Only following 3 categories can trigger CI :PR Author, MXNet Committer, Jenkins Admin.
All CI tests must pass before the PR can be merged.

[DanMcInerney]

This test is failing because an S3 bucket doesn't exist in the test cases. This PR shouldn't affect any usability or overhead.

[josephevans]

Hi, thanks for your contribution. Could you please rebase this PR so the required CI checks will pass? Thanks.

[DanMcInerney]

Yes, although I'm not clear on how to fix the fails. For example, this one seems to be failing because a bucket doesn't exist that I don't have control over?

ci/jenkins/mxnet-validation/website — Job failed
RuntimeError: Failed downloading url https://md-datasets-cache-zipfiles-prod.s3.eu-west-1.amazonaws.com/hb74ynkjcn-1.zip

[josephevans]

Yes, although I'm not clear on how to fix the fails. For example, this one seems to be failing because a bucket doesn't exist that I don't have control over?

ci/jenkins/mxnet-validation/website — Job failed RuntimeError: Failed downloading url https://md-datasets-cache-zipfiles-prod.s3.eu-west-1.amazonaws.com/hb74ynkjcn-1.zip

Hi Dan, the failing tests have been fixed in #21162, so if you rebase your PR, it should then pass all CI pipelines.