syzkaller的安装与运行

发表于 2021-06-25 |

syzkaller是一种无监督的覆盖引导内核模糊器。

支持的操作系统：Akaros, FreeBSD, Fuchsia, gVisor, Linux, NetBSD, OpenBSD, Windows.

对linux的支持最全面

syz-manager
1、启动、监控多个vm实例
2、复制syz-fuzzer到vm里面，并启动它
3、存储corpus和crashes
syz-fuzzer
1、fuzzing（输入生成、变异、最小化等）
2、通过RPC发送触发新路径的input给到syz-manager
3、启动syz-executor
syz-executor
执行每个input（就是系统调用的序列）
用C++编写，静态二进制，使用共享内存进行通信

依赖安装

1	apt install build-essential flex bison libssl-dev libelf-dev bc

下载源码编译

git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git kernel

cd kernel
# 生成默认配置

make defconfig
make kvm_guest.config

在.config文件中加入以下配置
vim .config

# Coverage collection.
CONFIG_KCOV=y

# Debug info for symbolization.
CONFIG_DEBUG_INFO=y

# Memory bug detector
CONFIG_KASAN=y
CONFIG_KASAN_INLINE=y

# Required for Debian Stretch
CONFIG_CONFIGFS_FS=y
CONFIG_SECURITYFS=y

# 由于启用这些选项会导致更多子选项可用，我们需要重新生成配置
make olddefconfig

make -j 16

创建镜像

apt-get install debootstrap

cd $IMAGE/
wget https://raw.githubusercontent.com/google/syzkaller/master/tools/create-image.sh -O create-image.sh
chmod +x create-image.sh
./create-image.sh

安装qemu

1	apt-get install qemu-system-x86

测试

qemu-system-x86_64 \
	-m 2G \
	-smp 2 \
	-kernel ./kernel/arch/x86/boot/bzImage \
	-append "console=ttyS0 root=/dev/sda earlyprintk=serial net.ifnames=0" \
	-drive file=./image/stretch.img,format=raw \
	-net user,host=10.0.2.10,hostfwd=tcp:127.0.0.1:10021-:22 \
	-net nic,model=e1000 \
	-enable-kvm \
	-nographic \
	-pidfile vm.pid \
	2>&1 | tee vm.log

试一下ssh是否能够连接

1	ssh -i image/stretch.id_rsa -p 10021 -o "StrictHostKeyChecking no" [email protected] -v

下载配置go

wget https://golang.org/dl/go1.16.5.linux-amd64.tar.gz

tar -xvf go1.16.5.linux-amd64.tar.gz

mv go goroot
mkdir gopath

export GOPATH=`pwd`/gopath
export GOROOT=`pwd`/goroot
export PATH=$GOPATH/bin:$PATH
export PATH=$GOROOT/bin:$PATH

下载syzkaller源码并编译，先配置代理

export https_proxy=http://XXX.XXX.XXX.XXX:1080

go get -u -d github.com/google/syzkaller/prog

cd gopath/src/github.com/google/syzkaller
make

编辑配置文件，路径注意修改

vim syz.cfg


{
	"target": "linux/amd64",
	"http": "127.0.0.1:56741",
	"workdir": "/root/gopath/src/github.com/google/syzkaller/workdir",
	"kernel_obj": "/root/kernel",
	"image": "/root/image/stretch.img",
	"sshkey": "/root/image/stretch.id_rsa",
	"syzkaller": "/root/gopath/src/github.com/google/syzkaller",
	"procs": 8,
	"type": "qemu",
	"vm": {
		"count": 4,
		"kernel": "/root/kernel/arch/x86/boot/bzImage",
		"cpu": 2,
		"mem": 2048
	}
}