gVisor is a user-space kernel, written in Go, that implements a substantial portion of the Linux system surface.
gVisor
uses linux
OS, but the special gvisor
VM type. There is nothing
special regarding gVisor
besides that. Here is an example manager config:
{
"name": "gvisor",
"target": "linux/amd64",
"http": ":12345",
"workdir": "/workdir",
"image": "/usr/local/bin/runsc",
"syzkaller": "/gopath/src/github.com/google/syzkaller",
"cover": false,
"procs": 8,
"type": "gvisor",
"vm": {
"count": 5,
"runsc_args": "-platform=kvm"
}
}
syz-execprog
can be used inside gVisor to (hopefully) reproduce crashes.
To run a single program inside a minimal gVisor sandbox, do the following.
- Build all of the syzkaller tools:
$ cd $SYZKALLER_DIR
$ make
- Build runsc:
$ cd $GVISOR_DIR
$ bazel build //runsc
- Create a
bundle/
directory with a config like the one below. Be sure to update the paths to thelinux_amd64
directory and input log/program file.
$ mkdir bundle
$ $EDITOR bundle/config.json
- Run gVisor:
$ sudo bazel-bin/runsc/linux_amd64_pure_stripped/runsc \
-platform=ptrace \
-file-access=shared \
-network=host \
run \
-bundle /PATH/TO/bundle/ \
syzkaller
- Remove container:
$ sudo bazel-bin/runsc/linux_amd64_pure_stripped/runsc delete -force syzkaller
Note that you'll want to adjust the runsc
args to match the config in which
the crash was discovered. You may also want to add -debug -strace
for more
debugging information.
You can also adjust the args to syz-execprog
in config.json
. e.g., add
-repeat
to repeat the program.
{
"root": {
"path": "/PATH/TO/syzkaller/bin/linux_amd64",
"readonly": true
},
"mounts": [
{
"destination": "/input",
"source": "/PATH/TO/INPUT/LOG",
"type": "bind",
"options": ["ro"]
}
],
"process":{
"args": ["/syz-execprog", "-executor=/syz-executor", "-cover=false", "-sandbox=none", "/input"],
"cwd": "/tmp",
"capabilities": {
"bounding": [
"CAP_CHOWN",
"CAP_DAC_OVERRIDE",
"CAP_DAC_READ_SEARCH",
"CAP_FOWNER",
"CAP_FSETID",
"CAP_KILL",
"CAP_SETGID",
"CAP_SETUID",
"CAP_SETPCAP",
"CAP_LINUX_IMMUTABLE",
"CAP_NET_BIND_SERVICE",
"CAP_NET_BROADCAST",
"CAP_NET_ADMIN",
"CAP_NET_RAW",
"CAP_IPC_LOCK",
"CAP_IPC_OWNER",
"CAP_SYS_MODULE",
"CAP_SYS_RAWIO",
"CAP_SYS_CHROOT",
"CAP_SYS_PTRACE",
"CAP_SYS_PACCT",
"CAP_SYS_ADMIN",
"CAP_SYS_BOOT",
"CAP_SYS_NICE",
"CAP_SYS_RESOURCE",
"CAP_SYS_TIME",
"CAP_SYS_TTY_CONFIG",
"CAP_MKNOD",
"CAP_LEASE",
"CAP_AUDIT_WRITE",
"CAP_AUDIT_CONTROL",
"CAP_SETFCAP",
"CAP_MAC_OVERRIDE",
"CAP_MAC_ADMIN",
"CAP_SYSLOG",
"CAP_WAKE_ALARM",
"CAP_BLOCK_SUSPEND",
"CAP_AUDIT_READ"
],
"effective": [
"CAP_CHOWN",
"CAP_DAC_OVERRIDE",
"CAP_DAC_READ_SEARCH",
"CAP_FOWNER",
"CAP_FSETID",
"CAP_KILL",
"CAP_SETGID",
"CAP_SETUID",
"CAP_SETPCAP",
"CAP_LINUX_IMMUTABLE",
"CAP_NET_BIND_SERVICE",
"CAP_NET_BROADCAST",
"CAP_NET_ADMIN",
"CAP_NET_RAW",
"CAP_IPC_LOCK",
"CAP_IPC_OWNER",
"CAP_SYS_MODULE",
"CAP_SYS_RAWIO",
"CAP_SYS_CHROOT",
"CAP_SYS_PTRACE",
"CAP_SYS_PACCT",
"CAP_SYS_ADMIN",
"CAP_SYS_BOOT",
"CAP_SYS_NICE",
"CAP_SYS_RESOURCE",
"CAP_SYS_TIME",
"CAP_SYS_TTY_CONFIG",
"CAP_MKNOD",
"CAP_LEASE",
"CAP_AUDIT_WRITE",
"CAP_AUDIT_CONTROL",
"CAP_SETFCAP",
"CAP_MAC_OVERRIDE",
"CAP_MAC_ADMIN",
"CAP_SYSLOG",
"CAP_WAKE_ALARM",
"CAP_BLOCK_SUSPEND",
"CAP_AUDIT_READ"
],
"inheritable": [
"CAP_CHOWN",
"CAP_DAC_OVERRIDE",
"CAP_DAC_READ_SEARCH",
"CAP_FOWNER",
"CAP_FSETID",
"CAP_KILL",
"CAP_SETGID",
"CAP_SETUID",
"CAP_SETPCAP",
"CAP_LINUX_IMMUTABLE",
"CAP_NET_BIND_SERVICE",
"CAP_NET_BROADCAST",
"CAP_NET_ADMIN",
"CAP_NET_RAW",
"CAP_IPC_LOCK",
"CAP_IPC_OWNER",
"CAP_SYS_MODULE",
"CAP_SYS_RAWIO",
"CAP_SYS_CHROOT",
"CAP_SYS_PTRACE",
"CAP_SYS_PACCT",
"CAP_SYS_ADMIN",
"CAP_SYS_BOOT",
"CAP_SYS_NICE",
"CAP_SYS_RESOURCE",
"CAP_SYS_TIME",
"CAP_SYS_TTY_CONFIG",
"CAP_MKNOD",
"CAP_LEASE",
"CAP_AUDIT_WRITE",
"CAP_AUDIT_CONTROL",
"CAP_SETFCAP",
"CAP_MAC_OVERRIDE",
"CAP_MAC_ADMIN",
"CAP_SYSLOG",
"CAP_WAKE_ALARM",
"CAP_BLOCK_SUSPEND",
"CAP_AUDIT_READ"
],
"permitted": [
"CAP_CHOWN",
"CAP_DAC_OVERRIDE",
"CAP_DAC_READ_SEARCH",
"CAP_FOWNER",
"CAP_FSETID",
"CAP_KILL",
"CAP_SETGID",
"CAP_SETUID",
"CAP_SETPCAP",
"CAP_LINUX_IMMUTABLE",
"CAP_NET_BIND_SERVICE",
"CAP_NET_BROADCAST",
"CAP_NET_ADMIN",
"CAP_NET_RAW",
"CAP_IPC_LOCK",
"CAP_IPC_OWNER",
"CAP_SYS_MODULE",
"CAP_SYS_RAWIO",
"CAP_SYS_CHROOT",
"CAP_SYS_PTRACE",
"CAP_SYS_PACCT",
"CAP_SYS_ADMIN",
"CAP_SYS_BOOT",
"CAP_SYS_NICE",
"CAP_SYS_RESOURCE",
"CAP_SYS_TIME",
"CAP_SYS_TTY_CONFIG",
"CAP_MKNOD",
"CAP_LEASE",
"CAP_AUDIT_WRITE",
"CAP_AUDIT_CONTROL",
"CAP_SETFCAP",
"CAP_MAC_OVERRIDE",
"CAP_MAC_ADMIN",
"CAP_SYSLOG",
"CAP_WAKE_ALARM",
"CAP_BLOCK_SUSPEND",
"CAP_AUDIT_READ"
],
"ambient": [
"CAP_CHOWN",
"CAP_DAC_OVERRIDE",
"CAP_DAC_READ_SEARCH",
"CAP_FOWNER",
"CAP_FSETID",
"CAP_KILL",
"CAP_SETGID",
"CAP_SETUID",
"CAP_SETPCAP",
"CAP_LINUX_IMMUTABLE",
"CAP_NET_BIND_SERVICE",
"CAP_NET_BROADCAST",
"CAP_NET_ADMIN",
"CAP_NET_RAW",
"CAP_IPC_LOCK",
"CAP_IPC_OWNER",
"CAP_SYS_MODULE",
"CAP_SYS_RAWIO",
"CAP_SYS_CHROOT",
"CAP_SYS_PTRACE",
"CAP_SYS_PACCT",
"CAP_SYS_ADMIN",
"CAP_SYS_BOOT",
"CAP_SYS_NICE",
"CAP_SYS_RESOURCE",
"CAP_SYS_TIME",
"CAP_SYS_TTY_CONFIG",
"CAP_MKNOD",
"CAP_LEASE",
"CAP_AUDIT_WRITE",
"CAP_AUDIT_CONTROL",
"CAP_SETFCAP",
"CAP_MAC_OVERRIDE",
"CAP_MAC_ADMIN",
"CAP_SYSLOG",
"CAP_WAKE_ALARM",
"CAP_BLOCK_SUSPEND",
"CAP_AUDIT_READ"
]
}
}
}
To build specific gVisor ver:
git clone https://github.com/google/gvisor
git checkout be6ffa78e4df78df13d004a17f2a8833305285c4
To build runsc:
bazel build --verbose_failures --collect_code_coverage --instrumentation_filter=//pkg/...,-//pkg/sentry/platform,-//pkg/ring0,-//pkg/coverage:coverage //runsc:runsc
To find runsc binary and get symbols
bazel aquery --collect_code_coverage --instrumentation_filter=//pkg/...,-//pkg/sentry/platform,-//pkg/ring0,-//pkg/coverage:coverage 'mnemonic("GoLink", //runsc:runsc)'
./bazel-out/k8-fastbuild-ST-a2b97ed4b8d6/bin/runsc/runsc_/runsc symbolize -all > symbolize_all_gvisor_be6ffa78e4df78df13d004a17f2a8833305285c4.txt