The Codex sandbox starts successfully and can read/write project files.

Start by reproducing the reported commands inside the Codex sandbox and compare them with the same commands in native WSL. Trace the sandbox runtime's handling of /dev/null and the Git invocation; done means reads and writes to /dev/null succeed and git status --short runs normally.

What version of the Codex App are you using (From “About Codex” dialog)?

26.707.7222

What subscription do you have?

Plus

What platform is your computer?

Windows

What issue are you seeing?

The Codex sandbox starts successfully and can read/write project files.

However, the sandbox denies writes to /dev/null even though the device exists with the correct permissions.

This breaks Git and any shell command that redirects output to /dev/null.

Additional diagnostics

The following commands were executed inside the Codex sandbox:

echo test >/dev/null
cat /dev/null
printf test >/dev/null

All three fail with:

Permission denied

This is reproducible across multiple workspaces.

The same commands succeed in the user's native WSL environment.

This strongly suggests that the Codex sandbox is preventing access to /dev/null, despite:

crw-rw-rw- 1 root root 1,3
Access: (0666/crw-rw-rw-)
uid=0(root)

The issue appears to be specific to the sandbox runtime rather than WSL itself.

What steps can reproduce the bug?

The issue is reproducible in multiple workspaces.

1. Open any workspace.
2. Ask Codex to execute:

ls -l /dev/null
stat /dev/null
echo test >/dev/null
git status --short

3. Observe the results.

What is the expected behavior?

Expected behavior

/dev/null should behave like a normal character device.

This should succeed:

echo test >/dev/null



Git should also work normally:

git status --short

---

## Actual behavior

````markdown
`ls` and `stat` report that `/dev/null` exists and has correct permissions:

```text
crw-rw-rw- 1 root root 1,3
Access: (0666/crw-rw-rw-)

But writing to it fails:

/bin/bash: /dev/null: Permission denied

Git then fails with:

fatal: could not open '/dev/null' for reading and writing: Permission denied

---



### Additional information

## Additional Information

````markdown
The sandbox reports:

```text
uid=0(root)

The same commands executed directly in WSL outside the Codex sandbox work correctly:

echo test >/dev/null

returns exit code 0.

This suggests the issue is specific to the Codex sandbox rather than WSL itself.