Block file-reading Git options

[Byron]

Tasks

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• refackiew

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Everything below this line was generated by Codex GPT-5.

Created by Codex on behalf of Byron. Byron will review before this is ready to merge.

Summary

• Reject file-reading options passed to blame APIs, including equivalent short and clustered forms.
• Inspect positional tag path/reference inputs and the legacy ref alias for unsafe file options.
• Reject the adjacent diff order-file input, including clustered forms, while preserving safe -S pickaxe behavior.

Advisories

• GHSA-5xxx-qhh7-9287
• GHSA-3wxw-xv34-2frg

Advisory summary

Both advisories are medium severity and affect the pip package GitPython through version 3.1.58. No patched version or CVE has been assigned yet. The change prevents caller-controlled Git options from reading local files through high-level blame and tag APIs, and closes the same class of issue in diff order-file handling.

Validation

• Focused regression tests: 4 passed
• test_diff.py: 23 passed; 1 unrelated local branch-fixture failure
• test_repo.py and test_refs.py: 108 passed, 2 skipped; 5 unrelated local environment/history failures
• Ruff on changed files
• git diff --check
• Codex commit review: no actionable findings after follow-up fixes

Git behavior reference: git.git cf5497b14c, including the documented file-input options for git blame, git diff, and git tag.

[Copilot]

Pull request overview

This PR tightens GitPython’s unsafe-option filtering to prevent caller-controlled Git options from reading (or writing) arbitrary local files through higher-level APIs (blame, tag creation, and diff), aligning with the referenced security advisories.

Changes:

• Extend unsafe option blocks for Repo.blame() / Repo.blame_incremental() (e.g., --contents, -S, --ignore-revs-file) including clustered short-option forms.
• Extend unsafe option blocks for diff APIs to reject -O (orderfile) including clustered forms while preserving safe -S pickaxe usage.
• Expand unsafe-option parsing to accept per-command “clusterable short options” so sequences like -wS... and -pO... are detected.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
test/test_repo.py	Adds regression coverage for newly blocked blame option spellings (including clustered short options).
test/test_refs.py	Adds regression coverage for unsafe tag message file options via positional args and legacy ref alias.
test/test_diff.py	Adds regression coverage for diff -O (orderfile) blocking and clustered forms; ensures -S remains allowed.
git/repo/base.py	Introduces per-command unsafe option lists for blame and diff; wires them into blame checks.
git/refs/tag.py	Expands tag unsafe-option checking to include positional inputs and ref-alias-sourced reference.
git/index/base.py	Switches index diff unsafe option list to the new diff-specific unsafe set and cluster parsing.
git/diff.py	Switches diff unsafe option list to the new diff-specific unsafe set and cluster parsing; updates docs.
git/cmd.py	Adds configurable clusterable-short-option support to Git.check_unsafe_options.

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[Copilot]

Pull request overview

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.

Suppressed comments (2)

git/refs/tag.py:139

• The legacy ref kwarg is used as an alias for the reference argument, but it is left in kwargs. Since repo.git.tag(*args, **kwargs) transforms kwargs into CLI options, this will pass an unsupported --ref=... option to git tag and can break callers using ref=. Pop it from kwargs when consuming it as an alias.

        if "ref" in kwargs and kwargs["ref"]:
            reference = kwargs["ref"]

test/test_diff.py:394

• The unsafe-diff option tests cover -O/clustered forms but not the equivalent long form --orderfile (or the orderfile= kwarg), which should be blocked for the same reason. Add regression coverage so bypasses via long-option spelling are caught.

        calls = (
            lambda target: commit.diff(output=target),
            lambda target: commit.diff(other=f"--output={target}"),
            lambda target: commit.diff(O=target),
            lambda target: commit.diff(other=f"-pO{target}"),

[Copilot]

Pull request overview

Copilot reviewed 11 out of 11 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 10 out of 10 changed files in this pull request and generated no new comments.