TOSS 5 must enable mitigations against processor-based vulnerabilities.

Kernel page-table isolation is a kernel feature that mitigates the Meltdown security vulnerability and hardens the kernel against attempts to bypass kernel address space layout randomization (KASLR).

Satisfies: SRG-OS-000095-GPOS-00049, SRG-OS-000433-GPOS-00193

Verify TOSS 5 enables kernel page-table isolation using the following command:

$ sudo grubby --info=ALL | grep pti

args="ro crashkernel=auto resume=/dev/mapper/rhel-swap rd.lvm.lv=rhel/root rd.lvm.lv=rhel/swap rhgb quiet fips=1 audit=1 audit_backlog_limit=8192 pti=on

If the "pti" entry does not equal "on" or is missing, this is a finding.

Configure TOSS 5 to enable kernel page-table isolation using the following command:

$ sudo grubby --update-kernel=ALL --args="pti=on"

Add or modify the following line in "/etc/default/grub" to ensure the configuration survives kernel updates:

GRUB_CMDLINE_LINUX="pti=on"