Grsecurity Patched Kernel Walkthrough

I figured I would write this for those who didnt want to use the pre patched tarball or just wanna learn to do it yourself.

First

cd /usr/src

wget http://www.kernel.org/pub/linux/kernel/v2.6/linux-2.6.21.3.tar.gz

tar zxvf linux-2.6.21.3.tar.gz

rm -rf linux

ln -s linux-2.6.21.3 linux

wget http://grsecurity.net/grsecurity-2.1.9-2.6.19.1-200612121859.patch.gz

gunzip < grsecurity-2.1.9-2.6.19.1-200612121859.patch.gz | patch -p0

cd linux

Do make menuconfig to set al your options, If you are copying over a current config for enterprise linux make sure you slect the new sata modules or kernel wont make.
To copy over a config from your distro kernel do “uname -r” then copy the config over from /boot, for example
cp /boot/config-2.6.9-42.0.10.EL .config

If you would like this pre configure one I made get it here. For this one most people should just have to change the processor type and features and perhaps some custom grsecurity modifications

wget nix101.com/kconf ; cp -R kconf .config

After you are done with your config, save it, then its time to start building the kernel.

make bzImage

make modules

make modules_install

make install

Now to configure grub in case there is a kernel panic. If your system doesnt boot back up in 5 minutes you can use a remote reboot to boot it back into old kernel, just make sure the old kernel is marked default in /boot/grub/grub.conf

grub
savedefault --default=0 --once
quit


Then reboot and you are ready to go. If it turns out you have no problems with new kernel then set it as default in grub.conf