[Linux] apply_patch can create files but cannot update existing files (fs sandbox helper status 182)

What issue are you seeing?

In a Codex workspace on Linux, apply_patch can create a new file but fails when updating that file or another existing file:

fs sandbox helper failed with status exit status: 182

This started today after the same workflow worked during the previous two days. Restarting Codex and reopening the workspace did not resolve it.

What steps can reproduce the bug?

1. In a Linux Codex workspace, run an apply_patch operation that creates a temporary file containing before. This succeeds.
2. Run an apply_patch operation that changes before to after in that file. This fails with status 182.
3. Restart Codex or reopen the workspace and repeat the update. It still fails.

Observed in the same workspace:

• sed can read existing files.
• cp can write existing files.
• apply_patch can create new files.
• apply_patch fails only when updating an existing file.

What is the expected behavior?

apply_patch should be able to create, update, and delete files in the workspace. Updating an existing file should complete successfully.

Additional information

• Environment: Linux (Kali), zsh.
• The failure is reproducible with a newly created file, so it does not appear to depend on repository contents.
• The error indicates a filesystem sandbox helper failure rather than a patch-content or repository error.
• Relevant documentation: https://developers.openai.com/api/docs/guides/latest-model?model=gpt-5.2

Start by reproducing the failure in the Linux fs sandbox helper through the apply_patch update path, using the create-then-update steps in the issue. Compare the update operation with the working create, sed, and cp cases to locate the failing boundary. Done means apply_patch can create, update, and delete files successfully in the reported workspace scenario.