landhb / nixmodule

Simple qemu wrapper to automatically test out-of-tree linux kernel modules against multiple kernel versions.

NixModule

Simple qemu wrapper to automatically test out-of-tree linux kernel modules across multiple kernel versions. The provided images all have KASAN to aide your development.

cargo install nixmodule

• Pre-Built Kernels
• Pre-Built Disk Images
• Using Other Kernels
• Using Other Disk Images

Example below running it against a single kernel, running without arguments tests against every kernel in your nixmodule-config.toml:

Pre-Built Kernels

Check nixmodule-config.toml for an example configuration using all of these images.

Version	BzImage	Headers	LTS?
5.17.2	bZimage	Headers
5.15.33	bZimage	Headers	Yes
5.10.110	bZimage	Headers	Yes
5.8.9	bZimage	Headers
5.4.188	bZimage	Headers	Yes
4.19.237	bZimage	Headers	Yes
4.14.275	bZimage	Headers	Yes
4.9.309	bZimage	Headers	Yes
4.4.302	bZimage	Headers	Yes

Pre-Built Disk Images

ImgName	Link	SSH Key
Cornerstone	Image	Key
Syzkaller Debian Buster	Image	Key
Syzkaller Debian Stretch	Image	Key

Using Other Kernels

Use the packing script

KERNEL=4.14.275 ./scripts/package.sh

This builds the required bzImage and an archive linux-$VERSION-headers.tar.gz containing the headers/module info required to build an out-of-tree kernel module.

Then add the new kernel to your configuration file nixmodule-config.toml:

[[kernels]]
version = "4.19.237"
url_base = "https://files.sboc.dev"
headers = "linux-headers/linux-4.19.237-headers.tar.gz" 
kernel = "linux-kernels/bzImage-linux-4.19.237"
runner = "qemu-system-x86_64"

[kernels.disk]
name = "stretch"
url_base = "https://files.sboc.dev"
path = "images/stretch/stretch.img"
sshkey = "images/stretch/stretch.id_rsa"
boot = "/dev/sda"

You can optionally disable kvm with:

kvm = false

And increase the boot timeout with:

timeout = 600

Without kvm you'll likely need to increase the default the timeout.

Using Other Disk Images

Fill out the [kernels.disk] entry for the kernel you'd like to use the new disk with:

[kernels.disk]
name = "stretch"
url_base = "https://files.sboc.dev"
path = "images/stretch/stretch.img"
sshkey = "images/stretch/stretch.id_rsa"
boot = "/dev/sda"

Boot should contain the partition to boot from. This is passed to qemu to append as kernel arguments:

-append "console=ttyS0 root=$BOOT earlyprintk=serial net.ifnames=0 nokaslr"