Files
llmx/codex-rs/linux-sandbox
Michael Bolin 80555d4ff2 feat: make .git read-only within a writable root when using Seatbelt (#1765)
To make `--full-auto` safer, this PR updates the Seatbelt policy so that
a `SandboxPolicy` with a `writable_root` that contains a `.git/`
_directory_ will make `.git/` _read-only_ (though as a follow-up, we
should also consider the case where `.git` is a _file_ with a `gitdir:
/path/to/actual/repo/.git` entry that should also be protected).

The two major changes in this PR:

- Updating `SandboxPolicy::get_writable_roots_with_cwd()` to return a
`Vec<WritableRoot>` instead of a `Vec<PathBuf>` where a `WritableRoot`
can specify a list of read-only subpaths.
- Updating `create_seatbelt_command_args()` to honor the read-only
subpaths in `WritableRoot`.

The logic to update the policy is a fairly straightforward update to
`create_seatbelt_command_args()`, but perhaps the more interesting part
of this PR is the introduction of an integration test in
`tests/sandbox.rs`. Leveraging the new API in #1785, we test
`SandboxPolicy` under various conditions, including ones where `$TMPDIR`
is not readable, which is critical for verifying the new behavior.

To ensure that Codex can run its own tests, e.g.:

```
just codex debug seatbelt --full-auto -- cargo test if_git_repo_is_writable_root_then_dot_git_folder_is_read_only
```

I had to introduce the use of `CODEX_SANDBOX=sandbox`, which is
comparable to how `CODEX_SANDBOX_NETWORK_DISABLED=1` was already being
used.

Adding a comparable change for Landlock will be done in a subsequent PR.
2025-08-01 16:11:24 -07:00
..
2025-07-30 18:37:00 -07:00

codex-linux-sandbox

This crate is responsible for producing:

  • a codex-linux-sandbox standalone executable for Linux that is bundled with the Node.js version of the Codex CLI
  • a lib crate that exposes the business logic of the executable as run_main() so that
    • the codex-exec CLI can check if its arg0 is codex-linux-sandbox and, if so, execute as if it were codex-linux-sandbox
    • this should also be true of the codex multitool CLI