storage: filesystem, Avoid overwriting loose obj files by pjbgf · Pull Request #1864 · go-git/go-git

pjbgf · 2026-02-24T23:06:04Z

Loose object files are content-addressable and imutable. They should be created on demand and deleted on repacking. However, they should not be overwritten - assuming the initial file isn't corrupted.

The previous lack of validation meant those files were being overwritten when in fact they could just be ignored. In Linux, this was a non-issue, however, in Windows this operation led to Access Denied errors.

Some additional moving parts of this fix:

go-billy: Align behaviour supporting dir.NewObject():
- Add support for Chmod in polyfill so that ChrootOS is able to chmod files.
- Ensure temporary directories are created for BoundOS to avoid errors when trying to create the temporary file used for loose files.
This PR:
- Ensure that in Windows, packed and loose object files are created as read-only, which in this case means setting the flag windows.FILE_ATTRIBUTE_READONLY via x/sys/windows.
- Skip renaming the temporary file into the existing loose object, instead simply delete the temporary file.
- Expand on testing of file permissions for packed and loose object files for both Windows and Linux.

Relates to:

Fixes #55.

Align behaviour with upstream and v6, whereby all loose and packed objects are saved on disk as read-only as they are not meant to be modified due to their nature, as they are content addressable files. Signed-off-by: Paulo Gomes <[email protected]>

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Pull request overview

This PR updates the storage/filesystem/dotgit writers to better respect the immutability of content-addressed Git object storage and to avoid Windows “Access Denied” failures when attempting to overwrite existing loose objects.

Changes:

Add OS-specific helpers to mark written pack/idx and loose object files as read-only (Windows file attribute vs Unix perms).
Update pack/object writer save paths to apply read-only permissions and avoid overwriting existing loose objects.
Expand/adjust tests to validate permissions and reproduce Issue #55; bump go-billy dependency to include required filesystem behavior.

Reviewed changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
storage/filesystem/dotgit/writers_windows.go	Adds Windows-specific permission handling via `FILE_ATTRIBUTE_READONLY`.
storage/filesystem/dotgit/writers_unix.go	Adds Unix permission handling via `Chmod(0444)` where supported.
storage/filesystem/dotgit/writers.go	Applies permission fixes after writing pack/idx and loose objects; skips overwriting loose objects.
storage/filesystem/dotgit/writers_test.go	Adds new permission-focused tests for pack and loose object writers across OSFS variants.
storage/filesystem/dotgit/dotgit_test.go	Adds regression test intended to reproduce Issue #55 behavior.
go.mod	Bumps `github.com/go-git/go-billy/v5` to `v5.8.0`.
go.sum	Updates sums for the `go-billy` version bump.

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storage/filesystem/dotgit/writers_windows.go

storage/filesystem/dotgit/writers.go

storage/filesystem/dotgit/dotgit_test.go

Loose object files are content-addressable and imutable. They should be created on demand and deleted on repacking. However, they should not be overwritten - assuming the initial file isn't corrupted. The previous lack of validation meant those files were being overwritten when in fact they could just be ignored. In Linux, this was a non-issue, however, in Windows this operation led to Access Denied errors. Some additional moving parts of this fix: - [go-billy](go-git/go-billy#187): Align behaviour supporting dir.NewObject(): - Add support for Chmod in polyfill so that ChrootOS is able to chmod files. - Ensure temporary directories are created for BoundOS to avoid errors when trying to create the temporary file used for loose files. - This PR: - Ensure that in Windows, packed and loose object files are created as read-only, which in this case means setting the flag windows.FILE_ATTRIBUTE_READONLY via x/sys/windows. - Skip renaming the temporary file into the existing loose object, instead simply delete the temporary file. Relates to: - Southclaws/sampctl#422 - git-bug/git-bug#1142 - entireio/cli#455 Signed-off-by: Paulo Gomes <[email protected]>

This PR contains the following updates: | Package | Change | [Age](https://docs.renovatebot.com/merge-confidence/) | [Confidence](https://docs.renovatebot.com/merge-confidence/) | |---|---|---|---| | [github.com/go-git/go-git/v5](https://github.com/go-git/go-git) | `v5.16.5` -> `v5.17.0` | ![age](https://developer.mend.io/api/mc/badges/age/go/github.com%2fgo-git%2fgo-git%2fv5/v5.17.0?slim=true) | ![confidence](https://developer.mend.io/api/mc/badges/confidence/go/github.com%2fgo-git%2fgo-git%2fv5/v5.16.5/v5.17.0?slim=true) | --- ### Release Notes <details> <summary>go-git/go-git (github.com/go-git/go-git/v5)</summary> ### [`v5.17.0`](https://github.com/go-git/go-git/releases/tag/v5.17.0) [Compare Source](go-git/go-git@v5.16.5...v5.17.0) #### What's Changed - build: Update module github.com/go-git/go-git/v5 to v5.16.5 \[SECURITY] (releases/v5.x) by [@go-git-renovate](https://github.com/go-git-renovate)\[bot] in [#1839](go-git/go-git#1839) - git: worktree, optimize infiles function for very large repos by [@k-anshul](https://github.com/k-anshul) in [#1853](go-git/go-git#1853) - git: Add strict checks for supported extensions by [@pjbgf](https://github.com/pjbgf) in [#1861](go-git/go-git#1861) - backport, git: Improve Status() speed with new index.ModTime check by [@cedric-appdirect](https://github.com/cedric-appdirect) in [#1862](go-git/go-git#1862) - storage: filesystem, Avoid overwriting loose obj files by [@pjbgf](https://github.com/pjbgf) in [#1864](go-git/go-git#1864) **Full Changelog**: <go-git/go-git@v5.16.5...v5.17.0> </details> --- ### Configuration 📅 **Schedule**: Branch creation - Between 12:00 AM and 03:59 AM ( * 0-3 * * * ) (UTC), Automerge - Between 12:00 AM and 03:59 AM ( * 0-3 * * * ) (UTC). 🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied. ♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox. 🔕 **Ignore**: Close this PR and you won't be reminded about this update again. --- - [ ] If you want to rebase/retry this PR, check this box --- This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).  Reviewed-on: https://code.forgejo.org/forgejo/runner/pulls/1410 Reviewed-by: Mathieu Fenniak <[email protected]> Co-authored-by: Renovate Bot <[email protected]> Co-committed-by: Renovate Bot <[email protected]>

This PR contains the following updates: | Package | Type | Update | Change | OpenSSF | |---|---|---|---|---| | [github.com/go-git/go-git/v5](https://github.com/go-git/go-git) | require | minor | `v5.16.5` → `v5.17.0` | [![OpenSSF Scorecard](https://api.securityscorecards.dev/projects/github.com/go-git/go-git/badge)](https://securityscorecards.dev/viewer/?uri=github.com/go-git/go-git) | --- > ⚠️ **Warning** > > Some dependencies could not be looked up. Check the Dependency Dashboard for more information. --- ### Release Notes <details> <summary>go-git/go-git (github.com/go-git/go-git/v5)</summary> ### [`v5.17.0`](https://github.com/go-git/go-git/releases/tag/v5.17.0) [Compare Source](go-git/go-git@v5.16.5...v5.17.0) #### What's Changed - build: Update module github.com/go-git/go-git/v5 to v5.16.5 \[SECURITY] (releases/v5.x) by [@go-git-renovate](https://github.com/go-git-renovate)\[bot] in [#1839](go-git/go-git#1839) - git: worktree, optimize infiles function for very large repos by [@k-anshul](https://github.com/k-anshul) in [#1853](go-git/go-git#1853) - git: Add strict checks for supported extensions by [@pjbgf](https://github.com/pjbgf) in [#1861](go-git/go-git#1861) - backport, git: Improve Status() speed with new index.ModTime check by [@cedric-appdirect](https://github.com/cedric-appdirect) in [#1862](go-git/go-git#1862) - storage: filesystem, Avoid overwriting loose obj files by [@pjbgf](https://github.com/pjbgf) in [#1864](go-git/go-git#1864) **Full Changelog**: <go-git/go-git@v5.16.5...v5.17.0> </details> --- ### Configuration 📅 **Schedule**: Branch creation - At 12:00 AM through 04:59 AM and 10:00 PM through 11:59 PM, Monday through Friday ( * 0-4,22-23 * * 1-5 ), Only on Sunday and Saturday ( * * * * 0,6 ) (UTC), Automerge - At any time (no schedule defined). 🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied. ♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox. 🔕 **Ignore**: Close this PR and you won't be reminded about this update again. --- - [ ] If you want to rebase/retry this PR, check this box --- This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).  Reviewed-on: https://altlinux.space/stapler/stplr/pulls/333 Co-authored-by: Renovate Bot <[email protected]> Co-committed-by: Renovate Bot <[email protected]>

pjbgf force-pushed the v5-issue-55 branch from 92f0d0e to db63759 Compare February 24, 2026 23:41

pjbgf marked this pull request as ready for review February 25, 2026 09:58

Copilot AI review requested due to automatic review settings February 25, 2026 09:58

Copilot started reviewing on behalf of pjbgf February 25, 2026 09:59 View session

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pjbgf force-pushed the v5-issue-55 branch from db63759 to 5290e52 Compare February 25, 2026 11:16

pjbgf merged commit bdf0688 into go-git:releases/v5.x Feb 25, 2026
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pjbgf deleted the v5-issue-55 branch February 25, 2026 12:41

pjbgf mentioned this pull request Feb 26, 2026

storage: filesystem, Avoid overwriting loose obj files #1867

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storage: filesystem, Avoid overwriting loose obj files#1864

storage: filesystem, Avoid overwriting loose obj files#1864
pjbgf merged 2 commits intogo-git:releases/v5.xfrom
pjbgf:v5-issue-55

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