## Why
The Linux sandbox uses bubblewrap for filesystem isolation and seccomp for syscall filtering, but its command type, syscall-filter module, and integration test suite still used Landlock names.
## What changed
- Rename `LandlockCommand` to `LinuxSandboxCommand`, `src/landlock.rs` to `src/seccomp.rs`, and `tests/suite/landlock.rs` to `tests/suite/sandbox.rs`, updating imports and existing tests.
- Clarify the retained legacy Landlock implementation and its filesystem-policy limitations.
- Update the README to describe existing network filtering, `AF_VSOCK` and `io_uring` restrictions, and managed-proxy Unix socket behavior, including allowed Unix socket pairs.
Sandbox enforcement behavior is unchanged.
GitOrigin-RevId: be4769d5a10b90605990eb58451e83fdf1c31222
## Why
Bubblewrap discovery probes executables before confinement. Excluding only the command's current directory leaves candidates in other writable roots eligible to run outside the sandbox.
## What changed
- Filter canonical `PATH` candidates using the filesystem policy and effective user permissions, including writable ancestors, symlinked roots, and full-disk write access. Preserve protected system installations while rejecting replaceable paths.
- Select the launcher with the command's permissions before the proc-mount preflight, retaining the bundled bubblewrap fallback.
- Use the effective permission profile and policy working directory for startup warning probes.
## Testing
Add unit coverage for writable roots, symlinks, read-only carveouts, replaceable parents, and full-disk policies. Add Linux integration tests showing writable `bwrap` candidates are neither probed nor launched, including when the command runs in a workspace subdirectory or uses managed networking with full-disk write access.
GitOrigin-RevId: 188c9f45e727eaace062f5abb1205dc23fdf3c51
## Why
Bazel builds did not embed the SHA-256 digest used to verify the bundled
`bwrap` binary at launch.
## What changed
- Strip the Bazel-built `bwrap`, generate its SHA-256 digest, and pass that
digest to `codex-linux-sandbox` through a compiler environment file.
- Report digest verification failures with exit code `8` instead of panicking.
- Add a Bazel integration test that accepts the original bundled binary and
rejects a tampered copy.
GitOrigin-RevId: 224eeb6ae3d1bfb100e048b296f75fd8ba109581
this dramatically improves time to run `cargo test -p codex-core` (~25x
speedup).
before:
```
cargo test -p codex-core 35.96s user 68.63s system 19% cpu 8:49.80 total
```
after:
```
cargo test -p codex-core 5.51s user 8.16s system 63% cpu 21.407 total
```
both tests measured "hot", i.e. on a 2nd run with no filesystem changes,
to exclude compile times.
approach inspired by [Delete Cargo Integration
Tests](https://matklad.github.io/2021/02/27/delete-cargo-integration-tests.html),
we move all test cases in tests/ into a single suite in order to have a
single binary, as there is significant overhead for each test binary
executed, and because test execution is only parallelized with a single
binary.
Michael Bolin