Kernel

Capabilities

Everything related to Linux capabilities, like articles and an overview of the available capabilities.

Overview of Linux capabilities

An overview of the available Linux capabilities that allow processes to perform privileged actions.

Overview of Linux syscalls

An overview of the available syscalls, or system functions, that allow processes to communicate with the kernel.

How to see kernel messages with journalctl

Learn how to show all kernel events by using journalctl and filter out the kernel entries in the journal.

Net

Learn about the sysctl command and the values related to the network class.

Sysctl: net.ipv4.ip_forward

The sysctl key net.ipv4.ip_forward key is used to define IP forwarding of IPv4 network packets. Learn about the possible values of this key and their meaning.

Sysctl: kernel.perf_event_paranoid

Understand and configure the sysctl kernel.perf_event_paranoid key, including the possible values and their meaning.

What is a tainted kernel

Learn what it means when the Linux kernel is marked as tainted, including finding the cause.

How to find the specific cause of a tainted kernel

Learn what it means when the Linux kernel is marked as tainted and in particular the underlying cause.

Kernel: Frequently Asked Questions

Frequently asked questions about the Linux kernel and kernel security.

Sysctl

Learn about the sysctl command and how it can help with kernel tunables to alter the system configuration and perform additional security hardening.

Kernel

Learn about the sysctl command and the values related to the kernel class.

Kernel.tainted

Understand and configure the sysctl kernel.tainted key, including the possible values and their meaning.

Kernel

Everything related to Linux kernel itself, from configuration to querying information.

Linux hardening with sysctl settings

The Linux kernel can be secured as well. Learn how system hardening principles can be applied using sysctl settings.

Kernel hardening: Disable and blacklist Linux modules

The Linux kernel provides modular support to allow loading kernel modules during runtime. To prevent security issues, learn how to disable or blacklisting.

Increase kernel integrity with disabled Linux kernel modules loading

The Linux kernel can be configured to disallow loading new kernel modules. Learn how to configure this.

How to check if your Arch Linux system needs a reboot

Want to check if a reboot of the system is needed on Arch Linux? Here is how that can be done including the relevant commands.

Protect against ptrace of processes: kernel.yama.ptrace_scope

Using the Linux Security Module (LSM) Yama we can protect the system against the usage of ptrace. The sysctl key kernel.yama.ptrace_scope sets the behavior.

Linux kernel security and how to improve it

Every system is as strong as its weakest link, especially the system kernel. This article explains Linux kernel security, what we can do and how to do so.