KGuard

Stack protection implemented using a modified Linux kernel

VM Setup

For the purposes of this project, we use VirtualBox to emulate a Linux environment. The testing environment is Ubuntu 18.04 Server. You can download the prebuilt VirtualBox OVA file. This file was built using Ubuntu 18.04 Server.

You can follow the same instructions as for Project 0, particularly those related to networking. To allow enough memory and CPU power to compile the kernel reasonably fast, you should additionally set the following options:

• Under System > Motherboard, increase Base Memory to (hopefully) 4096 MB.
• Under System > Processor, increase the number of Processors until you reach the red zone.

The disk space for the OVA file was set at 50 GB, so you should allow for that much space.

After starting VM, log into Ubuntu using user as username, and 263 as password. You should also be able to ssh into the VM.

Compiling and Installing the Kernel

Clone this repository and then run cd linux-4.17/. First, run

user@cs263$ cp /boot/config-$(uname -r) ../config.old

This will backup the old configuration. Then, run

user@cs263$ sudo make olddefconfig

At this point, you will likely be prompted to install many packages. Do it. Some of them are bison, flex, and bc. Possibly, you will also be asked to install gcc and make, but these should already come with the VM image. Then, run

user@cs263$ sudo make -j 4

This will take a while. The -j command sets the number of processors to be utilized during the compilation; you should set this to the same number as the number of processors in VM settings. In my case, with 4 processors, compilation took about 45 minutes. After the compilation is done, run

user@cs263$ sudo make modules_install -j 4

When this is done, run finally

user@cs263$ sudo make install -j 4

Now, reboot to apply changes. During reboot, you might see the GRUB bootloader menu; if this is the case go to Advanced options for Ubuntu and pick the 4.17 version of the kernel. Once the machine boots up, run the following command

user@cs263$ uname -r

If all went well, this command should output 4.17.0. If this is not the case, reboot again, and this time hold the shift key to force access to GRUB bootloader menu. Then, pick the 4.17 version.

Potential Troubleshooting

When I first did this, I set the amount of memory for my VM to 2 GB. Apparently, this was not enough, so when I installed the kernel and rebooted, I was getting a kernel panic because there was not enough memory.