| #!/bin/bash |
| # Copyright 2016 syzkaller project authors. All rights reserved. |
| # Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file. |
| |
| # create-image.sh creates a minimal Debian Linux image suitable for syzkaller. |
| |
| set -eux |
| |
| # Create a minimal Debian distribution in a directory. |
| DIR=chroot |
| PREINSTALL_PKGS=openssh-server,curl,tar,gcc,libc6-dev,time,strace,sudo,less,psmisc,selinux-utils,policycoreutils,checkpolicy,selinux-policy-default |
| |
| # If ADD_PACKAGE is not defined as an external environment variable, use our default packages |
| if [ -z ${ADD_PACKAGE+x} ]; then |
| ADD_PACKAGE="make,sysbench,git,vim,tmux,usbutils" |
| fi |
| |
| # Variables affected by options |
| RELEASE=stretch |
| FEATURE=minimal |
| PERF=false |
| |
| # Display help function |
| display_help() { |
| echo "Usage: $0 [option...] " >&2 |
| echo |
| echo " -d, --distribution Set on which debian distribution to create" |
| echo " -f, --feature Check what packages to install in the image, options are minimal, full" |
| echo " -h, --help Display help message" |
| echo " -p, --add-perf Add perf support with this option enabled. Please set envrionment variable \$KERNEL at first" |
| echo |
| } |
| |
| while true; do |
| if [ $# -eq 0 ];then |
| echo $# |
| break |
| fi |
| case "$1" in |
| -h | --help) |
| display_help |
| exit 0 |
| ;; |
| -d | --distribution) |
| RELEASE=$2 |
| shift 2 |
| ;; |
| -f | --feature) |
| FEATURE=$2 |
| shift 2 |
| ;; |
| -p | --add-perf) |
| PERF=true |
| shift 1 |
| ;; |
| -*) |
| echo "Error: Unknown option: $1" >&2 |
| exit 1 |
| ;; |
| *) # No more options |
| break |
| ;; |
| esac |
| done |
| |
| # Double check KERNEL when PERF is enabled |
| if [ $PERF = "true" ] && [ -z ${KERNEL+x} ]; then |
| echo "Please set KERNEL environment variable when PERF is enabled" |
| exit 1 |
| fi |
| |
| # If full feature is chosen, install more packages |
| if [ $FEATURE = "full" ]; then |
| PREINSTALL_PKGS=$PREINSTALL_PKGS","$ADD_PACKAGE |
| fi |
| |
| sudo rm -rf $DIR |
| mkdir -p $DIR |
| sudo debootstrap --include=$PREINSTALL_PKGS $RELEASE $DIR |
| |
| # Set some defaults and enable promtless ssh to the machine for root. |
| sudo sed -i '/^root/ { s/:x:/::/ }' $DIR/etc/passwd |
| echo 'T0:23:respawn:/sbin/getty -L ttyS0 115200 vt100' | sudo tee -a $DIR/etc/inittab |
| printf '\nauto eth0\niface eth0 inet dhcp\n' | sudo tee -a $DIR/etc/network/interfaces |
| echo '/dev/root / ext4 defaults 0 0' | sudo tee -a $DIR/etc/fstab |
| echo 'debugfs /sys/kernel/debug debugfs defaults 0 0' | sudo tee -a $DIR/etc/fstab |
| echo 'securityfs /sys/kernel/security securityfs defaults 0 0' | sudo tee -a $DIR/etc/fstab |
| echo 'configfs /sys/kernel/config/ configfs defaults 0 0' | sudo tee -a $DIR/etc/fstab |
| echo 'binfmt_misc /proc/sys/fs/binfmt_misc binfmt_misc defaults 0 0' | sudo tee -a $DIR/etc/fstab |
| echo "kernel.printk = 7 4 1 3" | sudo tee -a $DIR/etc/sysctl.conf |
| echo 'debug.exception-trace = 0' | sudo tee -a $DIR/etc/sysctl.conf |
| echo "net.core.bpf_jit_enable = 1" | sudo tee -a $DIR/etc/sysctl.conf |
| echo "net.core.bpf_jit_kallsyms = 1" | sudo tee -a $DIR/etc/sysctl.conf |
| echo "net.core.bpf_jit_harden = 0" | sudo tee -a $DIR/etc/sysctl.conf |
| echo "kernel.softlockup_all_cpu_backtrace = 1" | sudo tee -a $DIR/etc/sysctl.conf |
| echo "kernel.kptr_restrict = 0" | sudo tee -a $DIR/etc/sysctl.conf |
| echo "kernel.watchdog_thresh = 60" | sudo tee -a $DIR/etc/sysctl.conf |
| echo "net.ipv4.ping_group_range = 0 65535" | sudo tee -a $DIR/etc/sysctl.conf |
| echo -en "127.0.0.1\tlocalhost\n" | sudo tee $DIR/etc/hosts |
| echo "nameserver 8.8.8.8" | sudo tee -a $DIR/etc/resolve.conf |
| echo "syzkaller" | sudo tee $DIR/etc/hostname |
| ssh-keygen -f $RELEASE.id_rsa -t rsa -N '' |
| sudo mkdir -p $DIR/root/.ssh/ |
| cat $RELEASE.id_rsa.pub | sudo tee $DIR/root/.ssh/authorized_keys |
| |
| # Add perf support |
| if [ $PERF = "true" ]; then |
| cp -r $KERNEL $DIR/tmp/ |
| sudo chroot $DIR /bin/bash -c "apt-get update; apt-get install -y flex bison python-dev libelf-dev libunwind8-dev libaudit-dev libslang2-dev libperl-dev binutils-dev liblzma-dev libnuma-dev" |
| sudo chroot $DIR /bin/bash -c "cd /tmp/linux/tools/perf/; make" |
| sudo chroot $DIR /bin/bash -c "cp /tmp/linux/tools/perf/perf /usr/bin/" |
| rm -r $DIR/tmp/linux |
| fi |
| |
| # Build a disk image |
| dd if=/dev/zero of=$RELEASE.img bs=1M seek=2047 count=1 |
| sudo mkfs.ext4 -F $RELEASE.img |
| sudo mkdir -p /mnt/$DIR |
| sudo mount -o loop $RELEASE.img /mnt/$DIR |
| sudo cp -a $DIR/. /mnt/$DIR/. |
| sudo umount /mnt/$DIR |