Just like the Linux developers, in the wake of the Spectre and Meltdown CPU vulnerabilities DragonFlyBSD developers have also been working on a variety of security improvements.

DragonFlyBSD has already pushed Meltdown fixes and Spectre mitigation while their latest security work on this BSD operating system is a new security.ptr_restrict sysctl option.

When enabled, security.ptr_restrict is another small safeguard that aims to prevent leaking kernel addresses back to user-space. That's the jist of it outlined via this commit hitting the DragonFly tree today.

This new sysctl will be in the upcoming DragonFlyBSD 5.2 release.