CVE-2026-31431: The 9-Year Linux Root Bug
CVE-2026-31431 (copy.fail) lets any local user become root on virtually every Linux system since 2017. Here's what it is, why it matters, and how to fix it.
Tag: kernel
All the articles with the tag "kernel".
Remove all old installed but unused kernels
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Old kernels pile up in /boot and eat disk space — safely remove unused kernels on Ubuntu and Debian with apt and dpkg.
Linux Suspend and Hibernate: Teaching Your Machine to Take a Nap Without Dying
Linux suspend vs hibernate explained: sleep states, swap setup, initramfs resume hook, wake-on-LAN, lid close behavior, and fixing common hibernate failures on modern Linux systems.
Sysctl Tuning: The Linux Kernel Knobs That Actually Matter
Learn which sysctl parameters actually improve Linux server performance. Network tuning, memory management, and a ready-to-use sysctl.conf for Docker hosts.
Kernel Live Patching: Security Updates Without the 3am Reboot
Apply Linux kernel security patches without rebooting using kpatch and Canonical Livepatch. Keep servers secure and online simultaneously — here's the practical setup guide.
Tmpfs vs Ramfs: When Your Disk Is Too Slow and Your RAM Is Just Sitting There
Tmpfs vs ramfs explained: mount RAM-backed filesystems on Linux for blazing fast temp storage. Covers fstab, Docker tmpfs mounts, CI/CD use cases, and the key differences.
Your Server Doesn't Know What Random Means (And That's a Problem)
Linux entropy explained: /dev/random vs /dev/urandom, entropy pools, haveged, virtio-rng, and hardware RNG. Fix low entropy on VMs and containers for safe crypto key generation.
Linux Capabilities: Drop Root Without Breaking Everything
Learn Linux capabilities to drop root privileges without breaking your apps. Master cap_drop, cap_add in Docker, and setcap for fine-grained privilege control.
Ulimit, Cgroups, and the Art of Stopping Processes From Eating Your Server
Control runaway processes with ulimit and cgroups v2: per-process limits, systemd resource controls, Docker cgroup integration, and practical examples to prevent one service from killing your server.
The Linux OOM Killer: Why It's Killing Your App
Understand the OOM killer, read dmesg logs, protect critical processes with oom_score_adj.
/proc as a Debugging Tool
The /proc filesystem is a window into running processes. Learn to use it without extra tools.
Switch Ubuntu to Hardware Enablement (HWE)
The Ubuntu HWE kernel brings newer hardware support to LTS releases — how to switch from generic to HWE and what you gain.