Linux Kernel Exploitation
Linux kernel exploitation lab.
Slide: speakerdeck.com/yuawn/kernel-exploitation
Linux kernel exploitation techniques
- ret2user
- status switch
- modify cr4 register
- bypass smep
- bypass smap
- kpti
- fix cr3 register
- swapgs_restore_regs_and_return_to_usermode()
- kernel information leak
- useful kernel structure for UAF
- modprobe_path
- userfaultfd
- race condition
- setxattr
- setxattr + userfaultfd
- msg_msg
- signal handler
Prepare files needed to compile kernel module
wget https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.1.tar.xz
tar Jxvf linux-5.10.1.tar.xz
cp .config linux-5.10.1
cd linux-5.10.1
make menuconfig # load .config
make modules_prepareCompile linux kernel
sudo apt-get install build-essential libncurses-dev bison flex libssl-dev libelf-dev
wget https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.1.tar.xz
tar Jxvf linux-5.10.1.tar.xz
cp .config linux-5.10.1
cd linux-5.10.1
make menuconfig # load .config
make -j $(nproc)busybox
wget https://busybox.net/downloads/busybox-1.32.0.tar.bz2
tar jxvf busybox-1.32.0.tar.bz2
cd busybox-1.32.0
mkdir build
export BUSYBOX_BUILD=$(pwd)/build
make O=$BUSYBOX_BUILD defconfig
make O=$BUSYBOX_BUILD menuconfig # Settings -> Build Options: enable Build static binary (no shared libs)
cd $BUSYBOX_BUILD
make -j 4
make install -j 4initramfs
mkdir rootfs
cd rootfs
mkdir -pv {bin,sbin,etc,proc,dev,tmp,sys,usr/{bin,sbin}}
cp -r $BUSYBOX_BUILD/_install/* .
vim init # Create init file- Some files
- /etc/passwd
- /home/user
- /flag