GNU bash ShellShock bug and how to fix it on OS X

Update: A new bash patch is released as bash-4.3.26. This article is updated to include the new patch.

Recently another UNIX bug broke out: ShellShock bug in GNU bash, the most commonly-used UNIX shell. It allowed arbitrary code execution. which is bad.

Test code, if you want to check:

env "() { ;:}; echo gah" bash -c "echo test"

If you see both gah and test, your system is vulnerable! Read on!

Continue reading GNU bash ShellShock bug and how to fix it on OS X

SSD caching for Linux: bcache

So after all the mucking and messing I finally set up bcache on my desktop, running Ubuntu 14.04. I followed a modified procedure by my friend John and his article here (in Chinese) so I am rounding it up here, starting from a computer without an OS.

Continue reading SSD caching for Linux: bcache

Tutorial: Setting up 6in4 IPv6 on an Ubuntu router

Despite lack of ISP support, I gave myself IPv6 network access by making my router switch IPv6 packets over an 6in4 tunnel. My tunnel provider is Hurricane Electric.

This tutorial is about setting up IPv6 tunnelling and routing, NDP router advertisement and tackling dynamic address. Not all part of this tutorial will fit your needs.

Continue reading Tutorial: Setting up 6in4 IPv6 on an Ubuntu router

Upcycling old computers

Recently I dug out, and was donated some old computers. I cannot bear letting them hang still doing nothing, so I need to find them a purpose.

I slapped Linux into all of them and made them do something now. Read along to check out.

Continue reading Upcycling old computers

Raspbian Server Edition 2.5 Update

Finally the images are ready! Here are the links:

On top of basic Raspbian Server Edition installation with full jessie updates, I have added:

  • apache2, libapache2-mod-php5, mariadb-server: A complete LAMP stack
  • avahi-daemon: Bonjour, in order to make remote management easier
  • watchdog, bcm2708-wdog: Watchdog daemon
  • rng-tools, bcm2708-rng: Hardware radom number generator, helps hardening your crypto.
  • ipv6: Next generation Internet

Hope that deems useful.

Raspbian Server Edition forks: NK and AC

I have a thing of running my Raspberry Pi headless, using Raspbian Server Edition. Current versions of Raspbian Server Edition is sort of old now, though.

I am preparing two forks of Raspbian Server Edition, both based on upstream version 2.5:

  • RSE 2.5NK: Based on RSE 2.5, latest bootloader, kernel is from rpi-update.
  • RSE 2.5AC: Based on RSE 2.5, latest bootloader, kernel have Wolfson Audio Card support.
  • RSE 2.5NK+: Based on NK, added command-line GPIO utilities, LAMP stack and mod_suexec for apache. Intended to be used as a home automation hub.
  • RSE 2.5AC+: Like NK+, but based on AC kernel. Intended to be used as a DLNA/AirPlay target or multipurpose guitar effect stompbox.

Stuff is still being assembled, and I will publish torrents and download links once it is finished.