Remove the kernel mapping in user mode
An XCCDF Rule
Description
This feature reduces the number of hardware side channels by ensuring that the majority of
kernel addresses are not mapped into userspace.
This configuration is available from kernel 4.15, but may be available if backported
by distros.
The configuration that was used to build kernel is available at /boot/config-*.
To check the configuration value for CONFIG_PAGE_TABLE_ISOLATION, run the following command:
grep CONFIG_PAGE_TABLE_ISOLATION /boot/config-*
For each kernel installed, a line with value "y" should be returned.
warning alert: Warning
There is no remediation for this besides re-compiling the kernel with the appropriate value for the config.
Rationale
This is a countermeasure to the Meltdown attack.
- ID
- xccdf_org.ssgproject.content_rule_kernel_config_page_table_isolation
- Severity
- High
- References
- Updated