Linux Kernel Live Patching with kpatch

Kernel live patching allows you to apply critical security patches to the Linux kernel without rebooting the server. This is invaluable for production servers where uptime is critical.

Installing kpatch

# On Ubuntu/Debian
sudo apt install -y kpatch kpatch-build

# On RHEL/CentOS (built-in as kpatch)
sudo yum install kpatch

# Check current kernel
uname -r

Applying Live Patches

# List available patches
kpatch list

# Apply a patch
sudo kpatch load /path/to/patch.ko

# Verify patch is applied
kpatch list
dmesg | tail -5

Canonical Livepatch (Ubuntu)

Ubuntu offers the Livepatch service for automatic kernel patching:

sudo snap install canonical-livepatch
sudo canonical-livepatch enable YOUR_TOKEN
canonical-livepatch status --verbose

Summary

Kernel live patching is a powerful tool for maintaining security without downtime. For production VPS instances, consider enabling automatic live patching to stay protected against kernel vulnerabilities.