Ensure mounting of jffs2 filesystems is disabled

MediumLevel 1Automatedros

Description

The jffs2 (journaling flash filesystem 2) filesystem type is a log-structured filesystem used in flash memory devices. The audit requires the jffs2 module to be unloaded and blocked (modprobe -n -v reports install /bin/true). Host-level control from the CIS ROS Melodic benchmark (Ubuntu 18.04 robot hosts); run as root.

How it is checked

Audit method: Shell command

shell

command -v modprobe >/dev/null 2>&1 || exit 1
grep -qw '^jffs2' /proc/modules 2>/dev/null && { echo 'jffs2 is loaded'; exit 1; }
cfg=$(modprobe -n -v jffs2 2>&1)
case "$cfg" in *'install /bin/true'*|*'install /bin/false'*|*'not found'*) echo compliant; exit 0 ;; esac
modprobe --showconfig 2>/dev/null | grep -Eq '^\s*install\s+jffs2\s+/bin/(true|false)' && echo compliant || echo 'jffs2 can be loaded'

Expected output: compliant

How it is fixed

Fix method: Guidance or infrastructure patch

Edit or create a file in the /etc/modprobe.d/ directory ending in .conf Example: vi /etc/modprobe.d/jffs2.conf and add the following line: install jffs2 /bin/true Run the following command to unload the jffs2 module: # rmmod jffs2

Properties

Operating systems: Any
Tags: rosros1melodicsystem
Reference: CIS ROS Melodic Benchmark v1.0.0 - 1.1.1.3 Ensure mounting of jffs2 filesystems is disabled

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target ros