"Here, you see examples of four system calls - open, read, write and close. Don't fret over the details of the syntax; that's not important right now. The point is this: through these system calls (and a few others) the Linux kernel provides the illusion of a 'file' - a sequence of bytes of data that has a name - and protects you from the underlying details of tracks and sectors and heads and free block lists that you'd have to get into if you wanted to talk to the hardware directly. That's what we mean by an abstraction.

The first maintenance release of the Finnix 92.0 Linux distribution was released today by Ryan Finnie, its developer. The most significant feature of Finnix 92.1 (codename Crandon) is the new Debian 2.6.26-7 based Linux kernel. "Finnix 92.1 is a regular maintenance release. New features include Linux kernel 2.6.26, updated upstream software, and x86 boot menu cleanups." - said Ryan Finnie in the release announcement.

Finnix is an operating system designed to be used by system administrators for tasks like network monitoring, hard drives partitioning, rebuilding MBRs or installing other operating systems. Finnix 92.1 includes the following changes since the 92.0 release:

· The Linux kernel packages were updated to version 2.6.26 (based on Debian's 2.6.26-7);

Yesterday, November 27th, the Ubuntu developers discovered yet another security issue (actually, more than one) in the Linux kernel packages. These vulnerabilities affect the following Ubuntu distributions: 6.06 LTS, 7.10, 8.04 LTS and 8.10 (also applies to Kubuntu, Edubuntu and Xubuntu). The truth is that there are exactly nine (yes, 9) security issues (see below for details), therefore, it is strongly recommended to update your system as soon as possible!

The Ubuntu developers discovered that:

1. The Xen hypervisor block driver couldn't accurately validate incoming requests. Therefore, a user with root privileges could crash a system and cause a DoS (Denial of Service) attack by executing malicious I/O requests. This issue affects only Ubuntu 7.10.