Skip to navigation
SecuritySecurity Controls

Understand Filesystem Controls

View as MarkdownOpen in Claude

NemoClaw uses OpenShell filesystem policy to restrict access outside the writable agent state tree.

OpenShell covers additional filesystem enforcement details, including hard_requirement compatibility mode for Landlock and policy path validation rules. Refer to the Filesystem Controls section of the OpenShell Security Best Practices.

Read-Only System Paths

The container mounts system directories read-only to prevent the agent from modifying binaries, libraries, or configuration files.

AspectDetail
Default/usr, /lib, /proc, /dev/urandom, /app, /etc, /var/log, and /var/lib/dpkg are read-only.
What you can changeAdd or remove paths in the filesystem_policy.read_only section of the policy file.
Risk if relaxedMaking /usr or /lib writable lets the agent replace system binaries (such as curl or node) with trojanized versions. Making /etc writable lets the agent modify DNS resolution, TLS trust stores, or user accounts.
RecommendationNever make system paths writable. If the agent needs a writable location for generated files, use a subdirectory of /sandbox.

Agent Config Directory

The /sandbox/.openclaw directory contains the OpenClaw gateway configuration (model routing, CORS settings, channel config). The current entrypoint reads the gateway auth token from OpenClaw config when present, exports it as OPENCLAW_GATEWAY_TOKEN, and writes it to /tmp/nemoclaw-proxy-env.sh so interactive sandbox sessions can reach the gateway through system-wide shell hooks. The launch boundary removes OPENCLAW_GATEWAY_TOKEN from the gateway process environment and does not pass its value in process arguments.

In root mode, the gateway process still runs as the separate gateway user, but the token is intentionally available to sandbox shells for local gateway access.

Writable agent state such as plugins, skills, hooks, and workspace metadata lives directly under /sandbox/.openclaw.

This directory remains writable so the agent can manage its own config, install skills, and write standard home-directory state. NemoClaw does not provide post-provisioning immutability for the OpenClaw config or state tree.

  • DAC permissions (default). Sandbox-user images create /sandbox/.openclaw with native mode 0700 and openclaw.json with 0600. Root-mode images use 2770 (setgid sandbox:sandbox) and 0660 for the separate gateway identity. Rebuild existing sandboxes after updating NemoClaw to apply these defaults.
  • Native config ownership. OpenClaw owns openclaw.json after first launch. NemoClaw does not maintain a config hash, seal, last-good copy, recovery anchor, baseline, or config guard for this file. Use openclaw configure, openclaw config set, or openclaw config unset inside the sandbox.
  • Gateway token environment. The entrypoint exports OPENCLAW_GATEWAY_TOKEN and writes it to /tmp/nemoclaw-proxy-env.sh for interactive sandbox sessions. The gateway process reads the token from openclaw.json instead. Code running as the sandbox user can read that token while the file exists.
AspectDetail
DefaultThe sandbox user owns writable config and state, with private permissions for verified same-user launches. The entrypoint places OPENCLAW_GATEWAY_TOKEN in /tmp/nemoclaw-proxy-env.sh for interactive shells. The gateway process does not receive the token through its environment or process arguments.
What you can changeUse native OpenClaw commands for agent configuration. Use NemoClaw and OpenShell commands for inference routes, credential bindings, network policy, and sandbox lifecycle.
Risk of defaultA writable .openclaw directory lets the agent modify its own gateway config: disabling CORS or redirecting inference to an attacker-controlled endpoint.
RecommendationTreat agent config and state as agent-controlled. Keep credentials in OpenShell providers, restrict network policy, and recreate the sandbox from trusted state after suspected compromise.

Writable Paths

The agent has read-write access to /sandbox, /tmp, /dev/null, and /dev/pts.

AspectDetail
Default/sandbox (agent workspace), /tmp (temporary files), /dev/null, and /dev/pts (the devpts pseudo-terminal directory, required so PTY-based tools such as tmux, script, and interactive shells can allocate a terminal).
What you can changeAdd additional writable paths in filesystem_policy.read_write.
Risk if relaxedEach additional writable path expands the agent’s ability to persist data and potentially modify system behavior. Adding /var lets the agent write to log directories. Adding /home gives access to other user directories.
RecommendationKeep writable paths to /sandbox and /tmp. If the agent needs a persistent working directory, create a subdirectory under /sandbox.

Landlock LSM Enforcement

Landlock is a Linux Security Module that enforces filesystem access rules at the kernel level.

AspectDetail
Defaultcompatibility: best_effort. The entrypoint applies Landlock rules when the kernel supports them and silently skips them on older kernels.
What you can changeThis is a NemoClaw default, not a user-facing knob.
Risk if relaxedOn kernels without Landlock support (pre-5.13), filesystem restrictions rely solely on container mount configuration, which is less granular.
RecommendationRun on a kernel that supports Landlock (5.13+). Ubuntu 22.04 LTS and later include Landlock support.