blob: a3df995b6432e266ee725b8d11814480132bf647 [file] [log] [blame]
// Copyright 2017 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
use std;
use std::cmp::min;
use std::convert::TryFrom;
use std::error::Error as StdError;
use std::ffi::CStr;
use std::fmt::{self, Display};
use std::fs::{File, OpenOptions};
use std::io::{self, stdin, Read};
use std::mem;
use std::net::Ipv4Addr;
#[cfg(feature = "gpu")]
use std::num::NonZeroU8;
use std::num::ParseIntError;
use std::os::unix::io::{AsRawFd, FromRawFd, RawFd};
use std::os::unix::net::UnixStream;
use std::path::{Path, PathBuf};
use std::str;
use std::sync::{Arc, Barrier};
use std::thread;
use std::thread::JoinHandle;
use std::time::{Duration, SystemTime, UNIX_EPOCH};
use libc::{self, c_int, gid_t, uid_t};
use audio_streams::DummyStreamSource;
use devices::virtio::{self, VirtioDevice};
use devices::{
self, HostBackendDeviceProvider, PciDevice, VfioDevice, VfioPciDevice, VirtioPciDevice,
XhciController,
};
use io_jail::{self, Minijail};
use kvm::*;
use libcras::CrasClient;
use msg_socket::{MsgError, MsgReceiver, MsgSender, MsgSocket};
use net_util::{Error as NetError, MacAddress, Tap};
use rand_ish::SimpleRng;
use remain::sorted;
use resources::{Alloc, MmioType, SystemAllocator};
use sync::{Condvar, Mutex};
use sys_util::net::{UnixSeqpacket, UnixSeqpacketListener, UnlinkUnixSeqpacketListener};
use sys_util::{
self, block_signal, clear_signal, drop_capabilities, error, flock, get_blocked_signals,
get_group_id, get_user_id, getegid, geteuid, info, register_rt_signal_handler,
set_cpu_affinity, validate_raw_fd, warn, EventFd, FlockOperation, GuestAddress, GuestMemory,
Killable, MemoryMapping, PollContext, PollToken, Protection, SignalFd, Terminal, TimerFd,
WatchingEvents, SIGRTMIN,
};
use vhost;
use vm_control::{
BalloonControlCommand, BalloonControlRequestSocket, BalloonControlResponseSocket,
DiskControlCommand, DiskControlRequestSocket, DiskControlResponseSocket, DiskControlResult,
UsbControlSocket, VmControlResponseSocket, VmIrqRequest, VmIrqResponse, VmIrqResponseSocket,
VmMemoryControlRequestSocket, VmMemoryControlResponseSocket, VmMemoryRequest, VmMemoryResponse,
VmRunMode,
};
use crate::{Config, DiskOption, Executable, SharedDir, SharedDirKind, TouchDeviceOption};
use arch::{self, LinuxArch, RunnableLinuxVm, VirtioDeviceStub, VmComponents, VmImage};
#[cfg(any(target_arch = "arm", target_arch = "aarch64"))]
use aarch64::AArch64 as Arch;
#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
use x86_64::X8664arch as Arch;
#[cfg(feature = "gpu-forward")]
use render_node_forward::*;
#[cfg(not(feature = "gpu-forward"))]
type RenderNodeHost = ();
#[sorted]
#[derive(Debug)]
pub enum Error {
AddGpuDeviceMemory(sys_util::Error),
AddPmemDeviceMemory(sys_util::Error),
AllocateGpuDeviceAddress,
AllocatePmemDeviceAddress(resources::Error),
BalloonDeviceNew(virtio::BalloonError),
BlockDeviceNew(sys_util::Error),
BlockSignal(sys_util::signal::Error),
BuildVm(<Arch as LinuxArch>::Error),
ChownTpmStorage(sys_util::Error),
CloneEventFd(sys_util::Error),
CreateCrasClient(libcras::Error),
CreateDiskError(disk::Error),
CreateEventFd(sys_util::Error),
CreatePollContext(sys_util::Error),
CreateSignalFd(sys_util::SignalFdError),
CreateSocket(io::Error),
CreateTapDevice(NetError),
CreateTimerFd(sys_util::Error),
CreateTpmStorage(PathBuf, io::Error),
CreateUsbProvider(devices::usb::host_backend::error::Error),
CreateVfioDevice(devices::vfio::VfioError),
DeviceJail(io_jail::Error),
DevicePivotRoot(io_jail::Error),
Disk(io::Error),
DiskImageLock(sys_util::Error),
DropCapabilities(sys_util::Error),
FsDeviceNew(virtio::fs::Error),
GetMaxOpenFiles(io::Error),
InputDeviceNew(virtio::InputError),
InputEventsOpen(std::io::Error),
InvalidFdPath,
InvalidWaylandPath,
IoJail(io_jail::Error),
LoadKernel(Box<dyn StdError>),
NetDeviceNew(virtio::NetError),
OpenAndroidFstab(PathBuf, io::Error),
OpenBios(PathBuf, io::Error),
OpenInitrd(PathBuf, io::Error),
OpenKernel(PathBuf, io::Error),
OpenVinput(PathBuf, io::Error),
P9DeviceNew(virtio::P9Error),
ParseMaxOpenFiles(ParseIntError),
PivotRootDoesntExist(&'static str),
PmemDeviceImageTooBig,
PmemDeviceNew(sys_util::Error),
PollContextAdd(sys_util::Error),
PollContextDelete(sys_util::Error),
ReadLowmemAvailable(io::Error),
ReadLowmemMargin(io::Error),
RegisterBalloon(arch::DeviceRegistrationError),
RegisterBlock(arch::DeviceRegistrationError),
RegisterGpu(arch::DeviceRegistrationError),
RegisterNet(arch::DeviceRegistrationError),
RegisterP9(arch::DeviceRegistrationError),
RegisterRng(arch::DeviceRegistrationError),
RegisterSignalHandler(sys_util::Error),
RegisterWayland(arch::DeviceRegistrationError),
ReserveGpuMemory(sys_util::MmapError),
ReserveMemory(sys_util::Error),
ReservePmemMemory(sys_util::MmapError),
ResetTimerFd(sys_util::Error),
RngDeviceNew(virtio::RngError),
SettingGidMap(io_jail::Error),
SettingMaxOpenFiles(io_jail::Error),
SettingUidMap(io_jail::Error),
SignalFd(sys_util::SignalFdError),
SpawnVcpu(io::Error),
TimerFd(sys_util::Error),
ValidateRawFd(sys_util::Error),
VhostNetDeviceNew(virtio::vhost::Error),
VhostVsockDeviceNew(virtio::vhost::Error),
VirtioPciDev(sys_util::Error),
WaylandDeviceNew(sys_util::Error),
}
impl Display for Error {
#[remain::check]
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
use self::Error::*;
#[sorted]
match self {
AddGpuDeviceMemory(e) => write!(f, "failed to add gpu device memory: {}", e),
AddPmemDeviceMemory(e) => write!(f, "failed to add pmem device memory: {}", e),
AllocateGpuDeviceAddress => write!(f, "failed to allocate gpu device guest address"),
AllocatePmemDeviceAddress(e) => {
write!(f, "failed to allocate memory for pmem device: {}", e)
}
BalloonDeviceNew(e) => write!(f, "failed to create balloon: {}", e),
BlockDeviceNew(e) => write!(f, "failed to create block device: {}", e),
BlockSignal(e) => write!(f, "failed to block signal: {}", e),
BuildVm(e) => write!(f, "The architecture failed to build the vm: {}", e),
ChownTpmStorage(e) => write!(f, "failed to chown tpm storage: {}", e),
CloneEventFd(e) => write!(f, "failed to clone eventfd: {}", e),
CreateCrasClient(e) => write!(f, "failed to create cras client: {}", e),
CreateDiskError(e) => write!(f, "failed to create virtual disk: {}", e),
CreateEventFd(e) => write!(f, "failed to create eventfd: {}", e),
CreatePollContext(e) => write!(f, "failed to create poll context: {}", e),
CreateSignalFd(e) => write!(f, "failed to create signalfd: {}", e),
CreateSocket(e) => write!(f, "failed to create socket: {}", e),
CreateTapDevice(e) => write!(f, "failed to create tap device: {}", e),
CreateTimerFd(e) => write!(f, "failed to create timerfd: {}", e),
CreateTpmStorage(p, e) => {
write!(f, "failed to create tpm storage dir {}: {}", p.display(), e)
}
CreateUsbProvider(e) => write!(f, "failed to create usb provider: {}", e),
CreateVfioDevice(e) => write!(f, "Failed to create vfio device {}", e),
DeviceJail(e) => write!(f, "failed to jail device: {}", e),
DevicePivotRoot(e) => write!(f, "failed to pivot root device: {}", e),
Disk(e) => write!(f, "failed to load disk image: {}", e),
DiskImageLock(e) => write!(f, "failed to lock disk image: {}", e),
DropCapabilities(e) => write!(f, "failed to drop process capabilities: {}", e),
FsDeviceNew(e) => write!(f, "failed to create fs device: {}", e),
GetMaxOpenFiles(e) => write!(f, "failed to get max number of open files: {}", e),
InputDeviceNew(e) => write!(f, "failed to set up input device: {}", e),
InputEventsOpen(e) => write!(f, "failed to open event device: {}", e),
InvalidFdPath => write!(f, "failed parsing a /proc/self/fd/*"),
InvalidWaylandPath => write!(f, "wayland socket path has no parent or file name"),
IoJail(e) => write!(f, "{}", e),
LoadKernel(e) => write!(f, "failed to load kernel: {}", e),
NetDeviceNew(e) => write!(f, "failed to set up virtio networking: {}", e),
OpenAndroidFstab(p, e) => write!(
f,
"failed to open android fstab file {}: {}",
p.display(),
e
),
OpenBios(p, e) => write!(f, "failed to open bios {}: {}", p.display(), e),
OpenInitrd(p, e) => write!(f, "failed to open initrd {}: {}", p.display(), e),
OpenKernel(p, e) => write!(f, "failed to open kernel image {}: {}", p.display(), e),
OpenVinput(p, e) => write!(f, "failed to open vinput device {}: {}", p.display(), e),
P9DeviceNew(e) => write!(f, "failed to create 9p device: {}", e),
ParseMaxOpenFiles(e) => write!(f, "failed to parse max number of open files: {}", e),
PivotRootDoesntExist(p) => write!(f, "{} doesn't exist, can't jail devices.", p),
PmemDeviceImageTooBig => {
write!(f, "failed to create pmem device: pmem device image too big")
}
PmemDeviceNew(e) => write!(f, "failed to create pmem device: {}", e),
PollContextAdd(e) => write!(f, "failed to add fd to poll context: {}", e),
PollContextDelete(e) => write!(f, "failed to remove fd from poll context: {}", e),
ReadLowmemAvailable(e) => write!(
f,
"failed to read /sys/kernel/mm/chromeos-low_mem/available: {}",
e
),
ReadLowmemMargin(e) => write!(
f,
"failed to read /sys/kernel/mm/chromeos-low_mem/margin: {}",
e
),
RegisterBalloon(e) => write!(f, "error registering balloon device: {}", e),
RegisterBlock(e) => write!(f, "error registering block device: {}", e),
RegisterGpu(e) => write!(f, "error registering gpu device: {}", e),
RegisterNet(e) => write!(f, "error registering net device: {}", e),
RegisterP9(e) => write!(f, "error registering 9p device: {}", e),
RegisterRng(e) => write!(f, "error registering rng device: {}", e),
RegisterSignalHandler(e) => write!(f, "error registering signal handler: {}", e),
RegisterWayland(e) => write!(f, "error registering wayland device: {}", e),
ReserveGpuMemory(e) => write!(f, "failed to reserve gpu memory: {}", e),
ReserveMemory(e) => write!(f, "failed to reserve memory: {}", e),
ReservePmemMemory(e) => write!(f, "failed to reserve pmem memory: {}", e),
ResetTimerFd(e) => write!(f, "failed to reset timerfd: {}", e),
RngDeviceNew(e) => write!(f, "failed to set up rng: {}", e),
SettingGidMap(e) => write!(f, "error setting GID map: {}", e),
SettingMaxOpenFiles(e) => write!(f, "error setting max open files: {}", e),
SettingUidMap(e) => write!(f, "error setting UID map: {}", e),
SignalFd(e) => write!(f, "failed to read signal fd: {}", e),
SpawnVcpu(e) => write!(f, "failed to spawn VCPU thread: {}", e),
TimerFd(e) => write!(f, "failed to read timer fd: {}", e),
ValidateRawFd(e) => write!(f, "failed to validate raw fd: {}", e),
VhostNetDeviceNew(e) => write!(f, "failed to set up vhost networking: {}", e),
VhostVsockDeviceNew(e) => write!(f, "failed to set up virtual socket device: {}", e),
VirtioPciDev(e) => write!(f, "failed to create virtio pci dev: {}", e),
WaylandDeviceNew(e) => write!(f, "failed to create wayland device: {}", e),
}
}
}
impl From<io_jail::Error> for Error {
fn from(err: io_jail::Error) -> Self {
Error::IoJail(err)
}
}
impl std::error::Error for Error {}
type Result<T> = std::result::Result<T, Error>;
enum TaggedControlSocket {
Vm(VmControlResponseSocket),
VmMemory(VmMemoryControlResponseSocket),
VmIrq(VmIrqResponseSocket),
}
impl AsRef<UnixSeqpacket> for TaggedControlSocket {
fn as_ref(&self) -> &UnixSeqpacket {
use self::TaggedControlSocket::*;
match &self {
Vm(ref socket) => socket,
VmMemory(ref socket) => socket,
VmIrq(ref socket) => socket,
}
}
}
impl AsRawFd for TaggedControlSocket {
fn as_raw_fd(&self) -> RawFd {
self.as_ref().as_raw_fd()
}
}
fn get_max_open_files() -> Result<libc::rlim64_t> {
let mut buf = String::with_capacity(32);
File::open("/proc/sys/fs/file-max")
.and_then(|mut f| f.read_to_string(&mut buf))
.map_err(Error::GetMaxOpenFiles)?;
Ok(buf.trim().parse().map_err(Error::ParseMaxOpenFiles)?)
}
fn create_base_minijail(
root: &Path,
log_failures: bool,
seccomp_policy: &Path,
) -> Result<Minijail> {
// All child jails run in a new user namespace without any users mapped,
// they run as nobody unless otherwise configured.
let mut j = Minijail::new().map_err(Error::DeviceJail)?;
j.namespace_pids();
j.namespace_user();
j.namespace_user_disable_setgroups();
// Don't need any capabilities.
j.use_caps(0);
// Create a new mount namespace with an empty root FS.
j.namespace_vfs();
j.enter_pivot_root(root).map_err(Error::DevicePivotRoot)?;
// Run in an empty network namespace.
j.namespace_net();
// Most devices don't need to open many fds.
j.set_rlimit(libc::RLIMIT_NOFILE, 1024, 1024)
.map_err(Error::SettingMaxOpenFiles)?;
// Apply the block device seccomp policy.
j.no_new_privs();
// Use TSYNC only for the side effect of it using SECCOMP_RET_TRAP, which will correctly kill
// the entire device process if a worker thread commits a seccomp violation.
j.set_seccomp_filter_tsync();
if log_failures {
j.log_seccomp_filter_failures();
}
j.parse_seccomp_filters(seccomp_policy)
.map_err(Error::DeviceJail)?;
j.use_seccomp_filter();
// Don't do init setup.
j.run_as_init();
Ok(j)
}
fn simple_jail(cfg: &Config, policy: &str) -> Result<Option<Minijail>> {
if cfg.sandbox {
let pivot_root: &str = option_env!("DEFAULT_PIVOT_ROOT").unwrap_or("/var/empty");
// A directory for a jailed device's pivot root.
let root_path = Path::new(pivot_root);
if !root_path.exists() {
return Err(Error::PivotRootDoesntExist(pivot_root));
}
let policy_path: PathBuf = cfg.seccomp_policy_dir.join(policy);
Ok(Some(create_base_minijail(
root_path,
cfg.seccomp_log_failures,
&policy_path,
)?))
} else {
Ok(None)
}
}
type DeviceResult<T = VirtioDeviceStub> = std::result::Result<T, Error>;
fn create_block_device(
cfg: &Config,
disk: &DiskOption,
disk_device_socket: DiskControlResponseSocket,
) -> DeviceResult {
// Special case '/proc/self/fd/*' paths. The FD is already open, just use it.
let raw_image: File = if disk.path.parent() == Some(Path::new("/proc/self/fd")) {
// Safe because we will validate |raw_fd|.
unsafe { File::from_raw_fd(raw_fd_from_path(&disk.path)?) }
} else {
OpenOptions::new()
.read(true)
.write(!disk.read_only)
.open(&disk.path)
.map_err(Error::Disk)?
};
// Lock the disk image to prevent other crosvm instances from using it.
let lock_op = if disk.read_only {
FlockOperation::LockShared
} else {
FlockOperation::LockExclusive
};
flock(&raw_image, lock_op, true).map_err(Error::DiskImageLock)?;
let disk_file = disk::create_disk_file(raw_image).map_err(Error::CreateDiskError)?;
let dev = virtio::Block::new(
disk_file,
disk.read_only,
disk.sparse,
Some(disk_device_socket),
)
.map_err(Error::BlockDeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail: simple_jail(&cfg, "block_device.policy")?,
})
}
fn create_rng_device(cfg: &Config) -> DeviceResult {
let dev = virtio::Rng::new().map_err(Error::RngDeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail: simple_jail(&cfg, "rng_device.policy")?,
})
}
#[cfg(feature = "tpm")]
fn create_tpm_device(cfg: &Config) -> DeviceResult {
use std::ffi::CString;
use std::fs;
use std::process;
use sys_util::chown;
let tpm_storage: PathBuf;
let mut tpm_jail = simple_jail(&cfg, "tpm_device.policy")?;
match &mut tpm_jail {
Some(jail) => {
// Create a tmpfs in the device's root directory for tpm
// simulator storage. The size is 20*1024, or 20 KB.
jail.mount_with_data(
Path::new("none"),
Path::new("/"),
"tmpfs",
(libc::MS_NOSUID | libc::MS_NODEV | libc::MS_NOEXEC) as usize,
"size=20480",
)?;
let crosvm_ids = add_crosvm_user_to_jail(jail, "tpm")?;
let pid = process::id();
let tpm_pid_dir = format!("/run/vm/tpm.{}", pid);
tpm_storage = Path::new(&tpm_pid_dir).to_owned();
fs::create_dir_all(&tpm_storage)
.map_err(|e| Error::CreateTpmStorage(tpm_storage.to_owned(), e))?;
let tpm_pid_dir_c = CString::new(tpm_pid_dir).expect("no nul bytes");
chown(&tpm_pid_dir_c, crosvm_ids.uid, crosvm_ids.gid)
.map_err(Error::ChownTpmStorage)?;
jail.mount_bind(&tpm_storage, &tpm_storage, true)?;
}
None => {
// Path used inside cros_sdk which does not have /run/vm.
tpm_storage = Path::new("/tmp/tpm-simulator").to_owned();
}
}
let dev = virtio::Tpm::new(tpm_storage);
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail: tpm_jail,
})
}
fn create_single_touch_device(cfg: &Config, single_touch_spec: &TouchDeviceOption) -> DeviceResult {
let socket = create_input_socket(&single_touch_spec.path).map_err(|e| {
error!("failed configuring virtio single touch: {:?}", e);
e
})?;
let dev = virtio::new_single_touch(socket, single_touch_spec.width, single_touch_spec.height)
.map_err(Error::InputDeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail: simple_jail(&cfg, "input_device.policy")?,
})
}
fn create_trackpad_device(cfg: &Config, trackpad_spec: &TouchDeviceOption) -> DeviceResult {
let socket = create_input_socket(&trackpad_spec.path).map_err(|e| {
error!("failed configuring virtio trackpad: {}", e);
e
})?;
let dev = virtio::new_trackpad(socket, trackpad_spec.width, trackpad_spec.height)
.map_err(Error::InputDeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail: simple_jail(&cfg, "input_device.policy")?,
})
}
fn create_mouse_device(cfg: &Config, mouse_socket: &Path) -> DeviceResult {
let socket = create_input_socket(&mouse_socket).map_err(|e| {
error!("failed configuring virtio mouse: {}", e);
e
})?;
let dev = virtio::new_mouse(socket).map_err(Error::InputDeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail: simple_jail(&cfg, "input_device.policy")?,
})
}
fn create_keyboard_device(cfg: &Config, keyboard_socket: &Path) -> DeviceResult {
let socket = create_input_socket(&keyboard_socket).map_err(|e| {
error!("failed configuring virtio keyboard: {}", e);
e
})?;
let dev = virtio::new_keyboard(socket).map_err(Error::InputDeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail: simple_jail(&cfg, "input_device.policy")?,
})
}
fn create_vinput_device(cfg: &Config, dev_path: &Path) -> DeviceResult {
let dev_file = OpenOptions::new()
.read(true)
.write(true)
.open(dev_path)
.map_err(|e| Error::OpenVinput(dev_path.to_owned(), e))?;
let dev = virtio::new_evdev(dev_file).map_err(Error::InputDeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail: simple_jail(&cfg, "input_device.policy")?,
})
}
fn create_balloon_device(cfg: &Config, socket: BalloonControlResponseSocket) -> DeviceResult {
let dev = virtio::Balloon::new(socket).map_err(Error::BalloonDeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail: simple_jail(&cfg, "balloon_device.policy")?,
})
}
fn create_tap_net_device(cfg: &Config, tap_fd: RawFd) -> DeviceResult {
// Safe because we ensure that we get a unique handle to the fd.
let tap = unsafe {
Tap::from_raw_fd(validate_raw_fd(tap_fd).map_err(Error::ValidateRawFd)?)
.map_err(Error::CreateTapDevice)?
};
let dev = virtio::Net::from(tap).map_err(Error::NetDeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail: simple_jail(&cfg, "net_device.policy")?,
})
}
fn create_net_device(
cfg: &Config,
host_ip: Ipv4Addr,
netmask: Ipv4Addr,
mac_address: MacAddress,
mem: &GuestMemory,
) -> DeviceResult {
let dev = if cfg.vhost_net {
let dev =
virtio::vhost::Net::<Tap, vhost::Net<Tap>>::new(host_ip, netmask, mac_address, mem)
.map_err(Error::VhostNetDeviceNew)?;
Box::new(dev) as Box<dyn VirtioDevice>
} else {
let dev =
virtio::Net::<Tap>::new(host_ip, netmask, mac_address).map_err(Error::NetDeviceNew)?;
Box::new(dev) as Box<dyn VirtioDevice>
};
let policy = if cfg.vhost_net {
"vhost_net_device.policy"
} else {
"net_device.policy"
};
Ok(VirtioDeviceStub {
dev,
jail: simple_jail(&cfg, policy)?,
})
}
#[cfg(feature = "gpu")]
fn create_gpu_device(
cfg: &Config,
exit_evt: &EventFd,
gpu_device_socket: VmMemoryControlRequestSocket,
gpu_sockets: Vec<virtio::resource_bridge::ResourceResponseSocket>,
wayland_socket_path: Option<PathBuf>,
x_display: Option<String>,
) -> DeviceResult {
let jailed_wayland_path = Path::new("/wayland-0");
let mut display_backends = vec![
virtio::DisplayBackend::X(x_display),
virtio::DisplayBackend::Null,
];
if let Some(socket_path) = wayland_socket_path.as_ref() {
display_backends.insert(
0,
virtio::DisplayBackend::Wayland(if cfg.sandbox {
Some(jailed_wayland_path.to_owned())
} else {
Some(socket_path.to_owned())
}),
);
}
let dev = virtio::Gpu::new(
exit_evt.try_clone().map_err(Error::CloneEventFd)?,
Some(gpu_device_socket),
NonZeroU8::new(1).unwrap(), // number of scanouts
gpu_sockets,
display_backends,
);
let jail = match simple_jail(&cfg, "gpu_device.policy")? {
Some(mut jail) => {
// Create a tmpfs in the device's root directory so that we can bind mount the
// dri directory into it. The size=67108864 is size=64*1024*1024 or size=64MB.
jail.mount_with_data(
Path::new("none"),
Path::new("/"),
"tmpfs",
(libc::MS_NOSUID | libc::MS_NODEV | libc::MS_NOEXEC) as usize,
"size=67108864",
)?;
// Device nodes required for DRM.
let sys_dev_char_path = Path::new("/sys/dev/char");
jail.mount_bind(sys_dev_char_path, sys_dev_char_path, false)?;
let sys_devices_path = Path::new("/sys/devices");
jail.mount_bind(sys_devices_path, sys_devices_path, false)?;
let drm_dri_path = Path::new("/dev/dri");
jail.mount_bind(drm_dri_path, drm_dri_path, false)?;
// If the ARM specific devices exist on the host, bind mount them in.
let mali0_path = Path::new("/dev/mali0");
if mali0_path.exists() {
jail.mount_bind(mali0_path, mali0_path, true)?;
}
let pvr_sync_path = Path::new("/dev/pvr_sync");
if pvr_sync_path.exists() {
jail.mount_bind(pvr_sync_path, pvr_sync_path, true)?;
}
// Libraries that are required when mesa drivers are dynamically loaded.
let lib_dirs = &["/usr/lib", "/usr/lib64", "/lib", "/lib64"];
for dir in lib_dirs {
let dir_path = Path::new(dir);
if dir_path.exists() {
jail.mount_bind(dir_path, dir_path, false)?;
}
}
// Bind mount the wayland socket into jail's root. This is necessary since each
// new wayland context must open() the socket.
if let Some(path) = wayland_socket_path {
jail.mount_bind(path.as_ref(), jailed_wayland_path, true)?;
}
add_crosvm_user_to_jail(&mut jail, "gpu")?;
// pvr driver requires read access to /proc/self/task/*/comm.
let proc_path = Path::new("/proc");
jail.mount(
proc_path,
proc_path,
"proc",
(libc::MS_NOSUID | libc::MS_NODEV | libc::MS_NOEXEC | libc::MS_RDONLY) as usize,
)?;
Some(jail)
}
None => None,
};
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail,
})
}
fn create_wayland_device(
cfg: &Config,
socket_path: &Path,
socket: VmMemoryControlRequestSocket,
resource_bridge: Option<virtio::resource_bridge::ResourceRequestSocket>,
) -> DeviceResult {
let wayland_socket_dir = socket_path.parent().ok_or(Error::InvalidWaylandPath)?;
let wayland_socket_name = socket_path.file_name().ok_or(Error::InvalidWaylandPath)?;
let jailed_wayland_dir = Path::new("/wayland");
let jailed_wayland_path = jailed_wayland_dir.join(wayland_socket_name);
let dev = virtio::Wl::new(
if cfg.sandbox {
&jailed_wayland_path
} else {
socket_path
},
socket,
resource_bridge,
)
.map_err(Error::WaylandDeviceNew)?;
let jail = match simple_jail(&cfg, "wl_device.policy")? {
Some(mut jail) => {
// Create a tmpfs in the device's root directory so that we can bind mount the wayland
// socket directory into it. The size=67108864 is size=64*1024*1024 or size=64MB.
jail.mount_with_data(
Path::new("none"),
Path::new("/"),
"tmpfs",
(libc::MS_NOSUID | libc::MS_NODEV | libc::MS_NOEXEC) as usize,
"size=67108864",
)?;
// Bind mount the wayland socket's directory into jail's root. This is necessary since
// each new wayland context must open() the socket. If the wayland socket is ever
// destroyed and remade in the same host directory, new connections will be possible
// without restarting the wayland device.
jail.mount_bind(wayland_socket_dir, jailed_wayland_dir, true)?;
add_crosvm_user_to_jail(&mut jail, "Wayland")?;
Some(jail)
}
None => None,
};
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail,
})
}
fn create_vhost_vsock_device(cfg: &Config, cid: u64, mem: &GuestMemory) -> DeviceResult {
let dev = virtio::vhost::Vsock::new(cid, mem).map_err(Error::VhostVsockDeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail: simple_jail(&cfg, "vhost_vsock_device.policy")?,
})
}
fn create_fs_device(
cfg: &Config,
uid_map: &str,
gid_map: &str,
src: &Path,
tag: &str,
fs_cfg: virtio::fs::passthrough::Config,
) -> DeviceResult {
let mut j = Minijail::new().map_err(Error::DeviceJail)?;
if cfg.sandbox {
j.namespace_pids();
j.namespace_user();
j.namespace_user_disable_setgroups();
j.uidmap(uid_map).map_err(Error::SettingUidMap)?;
j.gidmap(gid_map).map_err(Error::SettingGidMap)?;
// Run in an empty network namespace.
j.namespace_net();
j.no_new_privs();
// Use TSYNC only for the side effect of it using SECCOMP_RET_TRAP, which will correctly kill
// the entire device process if a worker thread commits a seccomp violation.
let seccomp_policy = cfg.seccomp_policy_dir.join("fs_device.policy");
j.set_seccomp_filter_tsync();
if cfg.seccomp_log_failures {
j.log_seccomp_filter_failures();
}
j.parse_seccomp_filters(&seccomp_policy)
.map_err(Error::DeviceJail)?;
j.use_seccomp_filter();
// Don't do init setup.
j.run_as_init();
}
// Create a new mount namespace with the source directory as the root. We need this even when
// sandboxing is disabled as the server relies on the host kernel to prevent path traversals
// from leaking out of the shared directory.
j.namespace_vfs();
j.enter_pivot_root(src).map_err(Error::DevicePivotRoot)?;
// The file server opens a lot of fds and needs a really high open file limit.
let max_open_files = get_max_open_files()?;
j.set_rlimit(libc::RLIMIT_NOFILE, max_open_files, max_open_files)
.map_err(Error::SettingMaxOpenFiles)?;
// TODO(chirantan): Use more than one worker once the kernel driver has been fixed to not panic
// when num_queues > 1.
let dev = virtio::fs::Fs::new(tag, 1, fs_cfg).map_err(Error::FsDeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail: Some(j),
})
}
fn create_9p_device(cfg: &Config, src: &Path, tag: &str) -> DeviceResult {
let (jail, root) = match simple_jail(&cfg, "9p_device.policy")? {
Some(mut jail) => {
// The shared directory becomes the root of the device's file system.
let root = Path::new("/");
jail.mount_bind(src, root, true)?;
add_crosvm_user_to_jail(&mut jail, "p9")?;
(Some(jail), root)
}
None => {
// There's no bind mount so we tell the server to treat the source directory as the
// root.
(None, src)
}
};
let dev = virtio::P9::new(root, tag).map_err(Error::P9DeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev),
jail,
})
}
fn create_pmem_device(
cfg: &Config,
vm: &mut Vm,
resources: &mut SystemAllocator,
disk: &DiskOption,
index: usize,
) -> DeviceResult {
let fd = OpenOptions::new()
.read(true)
.write(!disk.read_only)
.open(&disk.path)
.map_err(Error::Disk)?;
let image_size = {
let metadata = std::fs::metadata(&disk.path).map_err(Error::Disk)?;
metadata.len()
};
let protection = {
if disk.read_only {
Protection::read()
} else {
Protection::read_write()
}
};
let memory_mapping = {
// Conversion from u64 to usize may fail on 32bit system.
let image_size = usize::try_from(image_size).map_err(|_| Error::PmemDeviceImageTooBig)?;
MemoryMapping::from_fd_offset_protection(&fd, image_size, 0, protection)
.map_err(Error::ReservePmemMemory)?
};
let mapping_address = resources
.mmio_allocator(MmioType::High)
.allocate_with_align(
image_size,
Alloc::PmemDevice(index),
format!("pmem_disk_image_{}", index),
// Linux kernel requires pmem namespaces to be 128 MiB aligned.
128 * 1024 * 1024, /* 128 MiB */
)
.map_err(Error::AllocatePmemDeviceAddress)?;
vm.add_mmio_memory(
GuestAddress(mapping_address),
memory_mapping,
/* read_only = */ disk.read_only,
/* log_dirty_pages = */ false,
)
.map_err(Error::AddPmemDeviceMemory)?;
let dev = virtio::Pmem::new(fd, GuestAddress(mapping_address), image_size)
.map_err(Error::PmemDeviceNew)?;
Ok(VirtioDeviceStub {
dev: Box::new(dev) as Box<dyn VirtioDevice>,
jail: simple_jail(&cfg, "pmem_device.policy")?,
})
}
// gpu_device_socket is not used when GPU support is disabled.
#[cfg_attr(not(feature = "gpu"), allow(unused_variables))]
fn create_virtio_devices(
cfg: &Config,
mem: &GuestMemory,
vm: &mut Vm,
resources: &mut SystemAllocator,
_exit_evt: &EventFd,
wayland_device_socket: VmMemoryControlRequestSocket,
gpu_device_socket: VmMemoryControlRequestSocket,
balloon_device_socket: BalloonControlResponseSocket,
disk_device_sockets: &mut Vec<DiskControlResponseSocket>,
) -> DeviceResult<Vec<VirtioDeviceStub>> {
let mut devs = Vec::new();
for disk in &cfg.disks {
let disk_device_socket = disk_device_sockets.remove(0);
devs.push(create_block_device(cfg, disk, disk_device_socket)?);
}
for (index, pmem_disk) in cfg.pmem_devices.iter().enumerate() {
devs.push(create_pmem_device(cfg, vm, resources, pmem_disk, index)?);
}
devs.push(create_rng_device(cfg)?);
#[cfg(feature = "tpm")]
{
if cfg.software_tpm {
devs.push(create_tpm_device(cfg)?);
}
}
if let Some(single_touch_spec) = &cfg.virtio_single_touch {
devs.push(create_single_touch_device(cfg, single_touch_spec)?);
}
if let Some(trackpad_spec) = &cfg.virtio_trackpad {
devs.push(create_trackpad_device(cfg, trackpad_spec)?);
}
if let Some(mouse_socket) = &cfg.virtio_mouse {
devs.push(create_mouse_device(cfg, mouse_socket)?);
}
if let Some(keyboard_socket) = &cfg.virtio_keyboard {
devs.push(create_keyboard_device(cfg, keyboard_socket)?);
}
for dev_path in &cfg.virtio_input_evdevs {
devs.push(create_vinput_device(cfg, dev_path)?);
}
devs.push(create_balloon_device(cfg, balloon_device_socket)?);
// We checked above that if the IP is defined, then the netmask is, too.
for tap_fd in &cfg.tap_fd {
devs.push(create_tap_net_device(cfg, *tap_fd)?);
}
if let (Some(host_ip), Some(netmask), Some(mac_address)) =
(cfg.host_ip, cfg.netmask, cfg.mac_address)
{
devs.push(create_net_device(cfg, host_ip, netmask, mac_address, mem)?);
}
#[cfg_attr(not(feature = "gpu"), allow(unused_mut))]
let mut resource_bridges = Vec::<virtio::resource_bridge::ResourceResponseSocket>::new();
if let Some(wayland_socket_path) = cfg.wayland_socket_path.as_ref() {
#[cfg_attr(not(feature = "gpu"), allow(unused_mut))]
let mut wl_resource_bridge = None::<virtio::resource_bridge::ResourceRequestSocket>;
#[cfg(feature = "gpu")]
{
if cfg.gpu {
let (wl_socket, gpu_socket) =
virtio::resource_bridge::pair().map_err(Error::CreateSocket)?;
resource_bridges.push(gpu_socket);
wl_resource_bridge = Some(wl_socket);
}
}
devs.push(create_wayland_device(
cfg,
wayland_socket_path,
wayland_device_socket,
wl_resource_bridge,
)?);
}
#[cfg(feature = "gpu")]
{
if cfg.gpu {
devs.push(create_gpu_device(
cfg,
_exit_evt,
gpu_device_socket,
resource_bridges,
cfg.wayland_socket_path.clone(),
cfg.x_display.clone(),
)?);
}
}
if let Some(cid) = cfg.cid {
devs.push(create_vhost_vsock_device(cfg, cid, mem)?);
}
for shared_dir in &cfg.shared_dirs {
let SharedDir {
src,
tag,
kind,
uid_map,
gid_map,
cfg: fs_cfg,
} = shared_dir;
let dev = match kind {
SharedDirKind::FS => create_fs_device(cfg, uid_map, gid_map, src, tag, fs_cfg.clone())?,
SharedDirKind::P9 => create_9p_device(cfg, src, tag)?,
};
devs.push(dev);
}
Ok(devs)
}
fn create_devices(
cfg: &Config,
mem: &GuestMemory,
vm: &mut Vm,
resources: &mut SystemAllocator,
exit_evt: &EventFd,
control_sockets: &mut Vec<TaggedControlSocket>,
wayland_device_socket: VmMemoryControlRequestSocket,
gpu_device_socket: VmMemoryControlRequestSocket,
balloon_device_socket: BalloonControlResponseSocket,
disk_device_sockets: &mut Vec<DiskControlResponseSocket>,
usb_provider: HostBackendDeviceProvider,
) -> DeviceResult<Vec<(Box<dyn PciDevice>, Option<Minijail>)>> {
let stubs = create_virtio_devices(
&cfg,
mem,
vm,
resources,
exit_evt,
wayland_device_socket,
gpu_device_socket,
balloon_device_socket,
disk_device_sockets,
)?;
let mut pci_devices = Vec::new();
for stub in stubs {
let dev = if stub.dev.msix_vectors() > 0 {
let (msi_host_socket, msi_device_socket) =
msg_socket::pair::<VmIrqResponse, VmIrqRequest>().map_err(Error::CreateSocket)?;
control_sockets.push(TaggedControlSocket::VmIrq(msi_host_socket));
VirtioPciDevice::new(mem.clone(), stub.dev, Some(msi_device_socket))
.map_err(Error::VirtioPciDev)?
} else {
VirtioPciDevice::new(mem.clone(), stub.dev, None).map_err(Error::VirtioPciDev)?
};
let dev = Box::new(dev) as Box<dyn PciDevice>;
pci_devices.push((dev, stub.jail));
}
if cfg.cras_audio {
let mut server = Box::new(CrasClient::new().map_err(Error::CreateCrasClient)?);
if cfg.cras_capture {
server.enable_cras_capture();
}
let cras_audio = devices::Ac97Dev::new(mem.clone(), server);
pci_devices.push((
Box::new(cras_audio),
simple_jail(&cfg, "cras_audio_device.policy")?,
));
}
if cfg.null_audio {
let server = Box::new(DummyStreamSource::new());
let null_audio = devices::Ac97Dev::new(mem.clone(), server);
pci_devices.push((
Box::new(null_audio),
simple_jail(&cfg, "null_audio_device.policy")?,
));
}
// Create xhci controller.
let usb_controller = Box::new(XhciController::new(mem.clone(), usb_provider));
pci_devices.push((usb_controller, simple_jail(&cfg, "xhci.policy")?));
if cfg.vfio.is_some() {
let (vfio_host_socket_irq, vfio_device_socket_irq) =
msg_socket::pair::<VmIrqResponse, VmIrqRequest>().map_err(Error::CreateSocket)?;
control_sockets.push(TaggedControlSocket::VmIrq(vfio_host_socket_irq));
let vfio_path = cfg.vfio.as_ref().unwrap().as_path();
let vfiodevice =
VfioDevice::new(vfio_path, vm, mem.clone()).map_err(Error::CreateVfioDevice)?;
let vfiopcidevice = Box::new(VfioPciDevice::new(vfiodevice, vfio_device_socket_irq));
pci_devices.push((vfiopcidevice, simple_jail(&cfg, "vfio_device.policy")?));
}
Ok(pci_devices)
}
#[derive(Copy, Clone)]
#[cfg_attr(not(feature = "tpm"), allow(dead_code))]
struct Ids {
uid: uid_t,
gid: gid_t,
}
// Set the uid/gid for the jailed process and give a basic id map. This is
// required for bind mounts to work.
fn add_crosvm_user_to_jail(jail: &mut Minijail, feature: &str) -> Result<Ids> {
let crosvm_user_group = CStr::from_bytes_with_nul(b"crosvm\0").unwrap();
let crosvm_uid = match get_user_id(&crosvm_user_group) {
Ok(u) => u,
Err(e) => {
warn!("falling back to current user id for {}: {}", feature, e);
geteuid()
}
};
let crosvm_gid = match get_group_id(&crosvm_user_group) {
Ok(u) => u,
Err(e) => {
warn!("falling back to current group id for {}: {}", feature, e);
getegid()
}
};
jail.change_uid(crosvm_uid);
jail.change_gid(crosvm_gid);
jail.uidmap(&format!("{0} {0} 1", crosvm_uid))
.map_err(Error::SettingUidMap)?;
jail.gidmap(&format!("{0} {0} 1", crosvm_gid))
.map_err(Error::SettingGidMap)?;
Ok(Ids {
uid: crosvm_uid,
gid: crosvm_gid,
})
}
fn raw_fd_from_path(path: &Path) -> Result<RawFd> {
if !path.is_file() {
return Err(Error::InvalidFdPath);
}
let raw_fd = path
.file_name()
.and_then(|fd_osstr| fd_osstr.to_str())
.and_then(|fd_str| fd_str.parse::<c_int>().ok())
.ok_or(Error::InvalidFdPath)?;
validate_raw_fd(raw_fd).map_err(Error::ValidateRawFd)
}
fn create_input_socket(path: &Path) -> Result<UnixStream> {
if path.parent() == Some(Path::new("/proc/self/fd")) {
// Safe because we will validate |raw_fd|.
unsafe { Ok(UnixStream::from_raw_fd(raw_fd_from_path(path)?)) }
} else {
UnixStream::connect(path).map_err(Error::InputEventsOpen)
}
}
fn setup_vcpu_signal_handler(use_kvm_signals: bool) -> Result<()> {
if use_kvm_signals {
unsafe {
extern "C" fn handle_signal() {}
// Our signal handler does nothing and is trivially async signal safe.
register_rt_signal_handler(SIGRTMIN() + 0, handle_signal)
.map_err(Error::RegisterSignalHandler)?;
}
block_signal(SIGRTMIN() + 0).map_err(Error::BlockSignal)?;
} else {
unsafe {
extern "C" fn handle_signal() {
Vcpu::set_local_immediate_exit(true);
}
register_rt_signal_handler(SIGRTMIN() + 0, handle_signal)
.map_err(Error::RegisterSignalHandler)?;
}
}
Ok(())
}
#[derive(Default)]
struct VcpuRunMode {
mtx: Mutex<VmRunMode>,
cvar: Condvar,
}
impl VcpuRunMode {
fn set_and_notify(&self, new_mode: VmRunMode) {
*self.mtx.lock() = new_mode;
self.cvar.notify_all();
}
}
fn run_vcpu(
mut vcpu: Vcpu,
cpu_id: u32,
vcpu_affinity: Vec<usize>,
start_barrier: Arc<Barrier>,
io_bus: devices::Bus,
mmio_bus: devices::Bus,
exit_evt: EventFd,
requires_kvmclock_ctrl: bool,
run_mode_arc: Arc<VcpuRunMode>,
use_kvm_signals: bool,
) -> Result<JoinHandle<()>> {
thread::Builder::new()
.name(format!("crosvm_vcpu{}", cpu_id))
.spawn(move || {
if vcpu_affinity.len() != 0 {
if let Err(e) = set_cpu_affinity(vcpu_affinity) {
error!("Failed to set CPU affinity: {}", e);
}
}
let mut sig_ok = true;
if use_kvm_signals {
match get_blocked_signals() {
Ok(mut v) => {
v.retain(|&x| x != SIGRTMIN() + 0);
if let Err(e) = vcpu.set_signal_mask(&v) {
error!(
"Failed to set the KVM_SIGNAL_MASK for vcpu {} : {}",
cpu_id, e
);
sig_ok = false;
}
}
Err(e) => {
error!(
"Failed to retrieve signal mask for vcpu {} : {}",
cpu_id, e
);
sig_ok = false;
}
};
} else {
vcpu.set_thread_id(SIGRTMIN() + 0);
}
start_barrier.wait();
if sig_ok {
'vcpu_loop: loop {
let mut interrupted_by_signal = false;
match vcpu.run() {
Ok(VcpuExit::IoIn { port, mut size }) => {
let mut data = [0; 8];
if size > data.len() {
error!("unsupported IoIn size of {} bytes", size);
size = data.len();
}
io_bus.read(port as u64, &mut data[..size]);
if let Err(e) = vcpu.set_data(&data[..size]) {
error!("failed to set return data for IoIn: {}", e);
}
}
Ok(VcpuExit::IoOut {
port,
mut size,
data,
}) => {
if size > data.len() {
error!("unsupported IoOut size of {} bytes", size);
size = data.len();
}
io_bus.write(port as u64, &data[..size]);
}
Ok(VcpuExit::MmioRead { address, size }) => {
let mut data = [0; 8];
mmio_bus.read(address, &mut data[..size]);
// Setting data for mmio can not fail.
let _ = vcpu.set_data(&data[..size]);
}
Ok(VcpuExit::MmioWrite {
address,
size,
data,
}) => {
mmio_bus.write(address, &data[..size]);
}
Ok(VcpuExit::Hlt) => break,
Ok(VcpuExit::Shutdown) => break,
Ok(VcpuExit::SystemEvent(_, _)) => break,
Ok(r) => warn!("unexpected vcpu exit: {:?}", r),
Err(e) => match e.errno() {
libc::EINTR => interrupted_by_signal = true,
libc::EAGAIN => {}
_ => {
error!("vcpu hit unknown error: {}", e);
break;
}
},
}
if interrupted_by_signal {
if use_kvm_signals {
// Try to clear the signal that we use to kick VCPU if it is pending before
// attempting to handle pause requests.
if let Err(e) = clear_signal(SIGRTMIN() + 0) {
error!("failed to clear pending signal: {}", e);
break;
}
} else {
vcpu.set_immediate_exit(false);
}
let mut run_mode_lock = run_mode_arc.mtx.lock();
loop {
match *run_mode_lock {
VmRunMode::Running => break,
VmRunMode::Suspending => {
// On KVM implementations that use a paravirtualized clock (e.g.
// x86), a flag must be set to indicate to the guest kernel that
// a VCPU was suspended. The guest kernel will use this flag to
// prevent the soft lockup detection from triggering when this
// VCPU resumes, which could happen days later in realtime.
if requires_kvmclock_ctrl {
if let Err(e) = vcpu.kvmclock_ctrl() {
error!("failed to signal to kvm that vcpu {} is being suspended: {}", cpu_id, e);
}
}
}
VmRunMode::Exiting => break 'vcpu_loop,
}
// Give ownership of our exclusive lock to the condition variable that
// will block. When the condition variable is notified, `wait` will
// unblock and return a new exclusive lock.
run_mode_lock = run_mode_arc.cvar.wait(run_mode_lock);
}
}
}
}
exit_evt
.write(1)
.expect("failed to signal vcpu exit eventfd");
})
.map_err(Error::SpawnVcpu)
}
// Reads the contents of a file and converts the space-separated fields into a Vec of u64s.
// Returns an error if any of the fields fail to parse.
fn file_fields_to_u64<P: AsRef<Path>>(path: P) -> io::Result<Vec<u64>> {
let mut file = File::open(path)?;
let mut buf = [0u8; 32];
let count = file.read(&mut buf)?;
let content =
str::from_utf8(&buf[..count]).map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
content
.trim()
.split_whitespace()
.map(|x| {
x.parse::<u64>()
.map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
})
.collect()
}
// Reads the contents of a file and converts them into a u64, and if there
// are multiple fields it only returns the first one.
fn file_to_u64<P: AsRef<Path>>(path: P) -> io::Result<u64> {
file_fields_to_u64(path)?
.into_iter()
.next()
.ok_or_else(|| io::Error::new(io::ErrorKind::InvalidData, "empty file"))
}
pub fn run_config(cfg: Config) -> Result<()> {
if cfg.sandbox {
// Printing something to the syslog before entering minijail so that libc's syslogger has a
// chance to open files necessary for its operation, like `/etc/localtime`. After jailing,
// access to those files will not be possible.
info!("crosvm entering multiprocess mode");
}
let (usb_control_socket, usb_provider) =
HostBackendDeviceProvider::new().map_err(Error::CreateUsbProvider)?;
// Masking signals is inherently dangerous, since this can persist across clones/execs. Do this
// before any jailed devices have been spawned, so that we can catch any of them that fail very
// quickly.
let sigchld_fd = SignalFd::new(libc::SIGCHLD).map_err(Error::CreateSignalFd)?;
let initrd_image = if let Some(initrd_path) = &cfg.initrd_path {
Some(File::open(initrd_path).map_err(|e| Error::OpenInitrd(initrd_path.clone(), e))?)
} else {
None
};
let vm_image = match cfg.executable_path {
Some(Executable::Kernel(ref kernel_path)) => VmImage::Kernel(
File::open(kernel_path).map_err(|e| Error::OpenKernel(kernel_path.to_path_buf(), e))?,
),
Some(Executable::Bios(ref bios_path)) => VmImage::Bios(
File::open(bios_path).map_err(|e| Error::OpenBios(bios_path.to_path_buf(), e))?,
),
_ => panic!("Did not receive a bios or kernel, should be impossible."),
};
let components = VmComponents {
memory_size: (cfg.memory.unwrap_or(256) << 20) as u64,
vcpu_count: cfg.vcpu_count.unwrap_or(1),
vcpu_affinity: cfg.vcpu_affinity.clone(),
vm_image,
android_fstab: cfg
.android_fstab
.as_ref()
.map(|x| File::open(x).map_err(|e| Error::OpenAndroidFstab(x.to_path_buf(), e)))
.map_or(Ok(None), |v| v.map(Some))?,
initrd_image,
extra_kernel_params: cfg.params.clone(),
wayland_dmabuf: cfg.wayland_dmabuf,
};
let control_server_socket = match &cfg.socket_path {
Some(path) => Some(UnlinkUnixSeqpacketListener(
UnixSeqpacketListener::bind(path).map_err(Error::CreateSocket)?,
)),
None => None,
};
let mut control_sockets = Vec::new();
let (wayland_host_socket, wayland_device_socket) =
msg_socket::pair::<VmMemoryResponse, VmMemoryRequest>().map_err(Error::CreateSocket)?;
control_sockets.push(TaggedControlSocket::VmMemory(wayland_host_socket));
// Balloon gets a special socket so balloon requests can be forwarded from the main process.
let (balloon_host_socket, balloon_device_socket) =
msg_socket::pair::<BalloonControlCommand, ()>().map_err(Error::CreateSocket)?;
// Create one control socket per disk.
let mut disk_device_sockets = Vec::new();
let mut disk_host_sockets = Vec::new();
let disk_count = cfg.disks.len();
for _ in 0..disk_count {
let (disk_host_socket, disk_device_socket) =
msg_socket::pair::<DiskControlCommand, DiskControlResult>()
.map_err(Error::CreateSocket)?;
disk_host_sockets.push(disk_host_socket);
disk_device_sockets.push(disk_device_socket);
}
let (gpu_host_socket, gpu_device_socket) =
msg_socket::pair::<VmMemoryResponse, VmMemoryRequest>().map_err(Error::CreateSocket)?;
control_sockets.push(TaggedControlSocket::VmMemory(gpu_host_socket));
let sandbox = cfg.sandbox;
let linux = Arch::build_vm(
components,
cfg.split_irqchip,
&cfg.serial_parameters,
simple_jail(&cfg, "serial.policy")?,
|mem, vm, sys_allocator, exit_evt| {
create_devices(
&cfg,
mem,
vm,
sys_allocator,
exit_evt,
&mut control_sockets,
wayland_device_socket,
gpu_device_socket,
balloon_device_socket,
&mut disk_device_sockets,
usb_provider,
)
},
)
.map_err(Error::BuildVm)?;
let _render_node_host = ();
#[cfg(feature = "gpu-forward")]
let (_render_node_host, linux) = {
// Rebinds linux as mutable.
let mut linux = linux;
// Reserve memory range for GPU buffer allocation in advance to bypass region count
// limitation. We use mremap/MAP_FIXED later to make sure GPU buffers fall into this range.
let gpu_mmap =
MemoryMapping::new_protection(RENDER_NODE_HOST_SIZE as usize, Protection::none())
.map_err(Error::ReserveGpuMemory)?;
// Put the non-accessible memory map into high mmio so that no other devices use that
// guest address space.
let gpu_addr = linux
.resources
.mmio_allocator(MmioType::High)
.allocate(
RENDER_NODE_HOST_SIZE,
Alloc::GpuRenderNode,
"gpu_render_node".to_string(),
)
.map_err(|_| Error::AllocateGpuDeviceAddress)?;
let host = RenderNodeHost::start(&gpu_mmap, gpu_addr, linux.vm.get_memory().clone());
// Makes the gpu memory accessible at allocated address.
linux
.vm
.add_mmio_memory(
GuestAddress(gpu_addr),
gpu_mmap,
/* read_only = */ false,
/* log_dirty_pages = */ false,
)
.map_err(Error::AddGpuDeviceMemory)?;
(host, linux)
};
run_control(
linux,
control_server_socket,
control_sockets,
balloon_host_socket,
&disk_host_sockets,
usb_control_socket,
sigchld_fd,
_render_node_host,
sandbox,
)
}
fn run_control(
mut linux: RunnableLinuxVm,
control_server_socket: Option<UnlinkUnixSeqpacketListener>,
mut control_sockets: Vec<TaggedControlSocket>,
balloon_host_socket: BalloonControlRequestSocket,
disk_host_sockets: &[DiskControlRequestSocket],
usb_control_socket: UsbControlSocket,
sigchld_fd: SignalFd,
_render_node_host: RenderNodeHost,
sandbox: bool,
) -> Result<()> {
// Paths to get the currently available memory and the low memory threshold.
const LOWMEM_MARGIN: &str = "/sys/kernel/mm/chromeos-low_mem/margin";
const LOWMEM_AVAILABLE: &str = "/sys/kernel/mm/chromeos-low_mem/available";
// The amount of additional memory to claim back from the VM whenever the system is
// low on memory.
const ONE_GB: u64 = (1 << 30);
let max_balloon_memory = match linux.vm.get_memory().memory_size() {
// If the VM has at least 1.5 GB, the balloon driver can consume all but the last 1 GB.
n if n >= (ONE_GB / 2) * 3 => n - ONE_GB,
// Otherwise, if the VM has at least 500MB the balloon driver will consume at most
// half of it.
n if n >= (ONE_GB / 2) => n / 2,
// Otherwise, the VM is too small for us to take memory away from it.
_ => 0,
};
let mut current_balloon_memory: u64 = 0;
let balloon_memory_increment: u64 = max_balloon_memory / 16;
#[derive(PollToken)]
enum Token {
Exit,
Stdin,
ChildSignal,
CheckAvailableMemory,
LowMemory,
LowmemTimer,
VmControlServer,
VmControl { index: usize },
}
let stdin_handle = stdin();
let stdin_lock = stdin_handle.lock();
stdin_lock
.set_raw_mode()
.expect("failed to set terminal raw mode");
let poll_ctx = PollContext::build_with(&[
(&linux.exit_evt, Token::Exit),
(&sigchld_fd, Token::ChildSignal),
])
.map_err(Error::PollContextAdd)?;
if let Err(e) = poll_ctx.add(&stdin_handle, Token::Stdin) {
warn!("failed to add stdin to poll context: {}", e);
}
if let Some(socket_server) = &control_server_socket {
poll_ctx
.add(socket_server, Token::VmControlServer)
.map_err(Error::PollContextAdd)?;
}
for (index, socket) in control_sockets.iter().enumerate() {
poll_ctx
.add(socket.as_ref(), Token::VmControl { index })
.map_err(Error::PollContextAdd)?;
}
// Watch for low memory notifications and take memory back from the VM.
let low_mem = File::open("/dev/chromeos-low-mem").ok();
if let Some(low_mem) = &low_mem {
poll_ctx
.add(low_mem, Token::LowMemory)
.map_err(Error::PollContextAdd)?;
} else {
warn!("Unable to open low mem indicator, maybe not a chrome os kernel");
}
// Used to rate limit balloon requests.
let mut lowmem_timer = TimerFd::new().map_err(Error::CreateTimerFd)?;
poll_ctx
.add(&lowmem_timer, Token::LowmemTimer)
.map_err(Error::PollContextAdd)?;
// Used to check whether it's ok to start giving memory back to the VM.
let mut freemem_timer = TimerFd::new().map_err(Error::CreateTimerFd)?;
poll_ctx
.add(&freemem_timer, Token::CheckAvailableMemory)
.map_err(Error::PollContextAdd)?;
// Used to add jitter to timer values so that we don't have a thundering herd problem when
// multiple VMs are running.
let mut simple_rng = SimpleRng::new(
SystemTime::now()
.duration_since(UNIX_EPOCH)
.expect("time went backwards")
.subsec_nanos() as u64,
);
if sandbox {
// Before starting VCPUs, in case we started with some capabilities, drop them all.
drop_capabilities().map_err(Error::DropCapabilities)?;
}
let mut vcpu_handles = Vec::with_capacity(linux.vcpus.len());
let vcpu_thread_barrier = Arc::new(Barrier::new(linux.vcpus.len() + 1));
let run_mode_arc = Arc::new(VcpuRunMode::default());
let use_kvm_signals = !linux.kvm.check_extension(Cap::ImmediateExit);
setup_vcpu_signal_handler(use_kvm_signals)?;
let vcpus = linux.vcpus.split_off(0);
for (cpu_id, vcpu) in vcpus.into_iter().enumerate() {
let handle = run_vcpu(
vcpu,
cpu_id as u32,
linux.vcpu_affinity.clone(),
vcpu_thread_barrier.clone(),
linux.io_bus.clone(),
linux.mmio_bus.clone(),
linux.exit_evt.try_clone().map_err(Error::CloneEventFd)?,
linux.vm.check_extension(Cap::KvmclockCtrl),
run_mode_arc.clone(),
use_kvm_signals,
)?;
vcpu_handles.push(handle);
}
vcpu_thread_barrier.wait();
'poll: loop {
let events = {
match poll_ctx.wait() {
Ok(v) => v,
Err(e) => {
error!("failed to poll: {}", e);
break;
}
}
};
let mut vm_control_indices_to_remove = Vec::new();
for event in events.iter_readable() {
match event.token() {
Token::Exit => {
info!("vcpu requested shutdown");
break 'poll;
}
Token::Stdin => {
let mut out = [0u8; 64];
match stdin_lock.read_raw(&mut out[..]) {
Ok(0) => {
// Zero-length read indicates EOF. Remove from pollables.
let _ = poll_ctx.delete(&stdin_handle);
}
Err(e) => {
warn!("error while reading stdin: {}", e);
let _ = poll_ctx.delete(&stdin_handle);
}
Ok(count) => {
if let Some(ref stdio_serial) = linux.stdio_serial {
stdio_serial
.queue_input_bytes(&out[..count])
.expect("failed to queue bytes into serial port");
}
}
}
}
Token::ChildSignal => {
// Print all available siginfo structs, then exit the loop.
while let Some(siginfo) = sigchld_fd.read().map_err(Error::SignalFd)? {
let pid = siginfo.ssi_pid;
let pid_label = match linux.pid_debug_label_map.get(&pid) {
Some(label) => format!("{} (pid {})", label, pid),
None => format!("pid {}", pid),
};
error!(
"child {} died: signo {}, status {}, code {}",
pid_label, siginfo.ssi_signo, siginfo.ssi_status, siginfo.ssi_code
);
}
break 'poll;
}
Token::CheckAvailableMemory => {
// Acknowledge the timer.
freemem_timer.wait().map_err(Error::TimerFd)?;
if current_balloon_memory == 0 {
// Nothing to see here.
if let Err(e) = freemem_timer.clear() {
warn!("unable to clear available memory check timer: {}", e);
}
continue;
}
// Otherwise see if we can free up some memory.
let margin = file_to_u64(LOWMEM_MARGIN).map_err(Error::ReadLowmemMargin)?;
let available =
file_to_u64(LOWMEM_AVAILABLE).map_err(Error::ReadLowmemAvailable)?;
// `available` and `margin` are specified in MB while `balloon_memory_increment` is in
// bytes. So to correctly compare them we need to turn the increment value into MB.
if available >= margin + 2 * (balloon_memory_increment >> 20) {
current_balloon_memory =
if current_balloon_memory >= balloon_memory_increment {
current_balloon_memory - balloon_memory_increment
} else {
0
};
let command = BalloonControlCommand::Adjust {
num_bytes: current_balloon_memory,
};
if let Err(e) = balloon_host_socket.send(&command) {
warn!("failed to send memory value to balloon device: {}", e);
}
}
}
Token::LowMemory => {
if let Some(low_mem) = &low_mem {
let old_balloon_memory = current_balloon_memory;
current_balloon_memory = min(
current_balloon_memory + balloon_memory_increment,
max_balloon_memory,
);
if current_balloon_memory != old_balloon_memory {
let command = BalloonControlCommand::Adjust {
num_bytes: current_balloon_memory,
};
if let Err(e) = balloon_host_socket.send(&command) {
warn!("failed to send memory value to balloon device: {}", e);
}
}
// Stop polling the lowmem device until the timer fires.
poll_ctx.delete(low_mem).map_err(Error::PollContextDelete)?;
// Add some jitter to the timer so that if there are multiple VMs running
// they don't all start ballooning at exactly the same time.
let lowmem_dur = Duration::from_millis(1000 + simple_rng.rng() % 200);
lowmem_timer
.reset(lowmem_dur, None)
.map_err(Error::ResetTimerFd)?;
// Also start a timer to check when we can start giving memory back. Do the
// first check after a minute (with jitter) and subsequent checks after
// every 30 seconds (with jitter).
let freemem_dur = Duration::from_secs(60 + simple_rng.rng() % 12);
let freemem_int = Duration::from_secs(30 + simple_rng.rng() % 6);
freemem_timer
.reset(freemem_dur, Some(freemem_int))
.map_err(Error::ResetTimerFd)?;
}
}
Token::LowmemTimer => {
// Acknowledge the timer.
lowmem_timer.wait().map_err(Error::TimerFd)?;
if let Some(low_mem) = &low_mem {
// Start polling the lowmem device again.
poll_ctx
.add(low_mem, Token::LowMemory)
.map_err(Error::PollContextAdd)?;
}
}
Token::VmControlServer => {
if let Some(socket_server) = &control_server_socket {
match socket_server.accept() {
Ok(socket) => {
poll_ctx
.add(
&socket,
Token::VmControl {
index: control_sockets.len(),
},
)
.map_err(Error::PollContextAdd)?;
control_sockets
.push(TaggedControlSocket::Vm(MsgSocket::new(socket)));
}
Err(e) => error!("failed to accept socket: {}", e),
}
}
}
Token::VmControl { index } => {
if let Some(socket) = control_sockets.get(index) {
match socket {
TaggedControlSocket::Vm(socket) => match socket.recv() {
Ok(request) => {
let mut run_mode_opt = None;
let response = request.execute(
&mut run_mode_opt,
&balloon_host_socket,
disk_host_sockets,
&usb_control_socket,
);
if let Err(e) = socket.send(&response) {
error!("failed to send VmResponse: {}", e);
}
if let Some(run_mode) = run_mode_opt {
info!("control socket changed run mode to {}", run_mode);
match run_mode {
VmRunMode::Exiting => {
break 'poll;
}
other => {
run_mode_arc.set_and_notify(other);
for handle in &vcpu_handles {
let _ = handle.kill(SIGRTMIN() + 0);
}
}
}
}
}
Err(e) => {
if let MsgError::BadRecvSize { actual: 0, .. } = e {
vm_control_indices_to_remove.push(index);
} else {
error!("failed to recv VmRequest: {}", e);
}
}
},
TaggedControlSocket::VmMemory(socket) => match socket.recv() {
Ok(request) => {
let response =
request.execute(&mut linux.vm, &mut linux.resources);
if let Err(e) = socket.send(&response) {
error!("failed to send VmMemoryControlResponse: {}", e);
}
}
Err(e) => {
if let MsgError::BadRecvSize { actual: 0, .. } = e {
vm_control_indices_to_remove.push(index);
} else {
error!("failed to recv VmMemoryControlRequest: {}", e);
}
}
},
TaggedControlSocket::VmIrq(socket) => match socket.recv() {
Ok(request) => {
let response =
request.execute(&mut linux.vm, &mut linux.resources);
if let Err(e) = socket.send(&response) {
error!("failed to send VmIrqResponse: {}", e);
}
}
Err(e) => {
if let MsgError::BadRecvSize { actual: 0, .. } = e {
vm_control_indices_to_remove.push(index);
} else {
error!("failed to recv VmIrqRequest: {}", e);
}
}
},
}
}
}
}
}
for event in events.iter_hungup() {
match event.token() {
Token::Exit => {}
Token::Stdin => {
let _ = poll_ctx.delete(&stdin_handle);
}
Token::ChildSignal => {}
Token::CheckAvailableMemory => {}
Token::LowMemory => {}
Token::LowmemTimer => {}
Token::VmControlServer => {}
Token::VmControl { index } => {
// It's possible more data is readable and buffered while the socket is hungup,
// so don't delete the socket from the poll context until we're sure all the
// data is read.
match control_sockets
.get(index)
.map(|s| s.as_ref().get_readable_bytes())
{
Some(Ok(0)) | Some(Err(_)) => vm_control_indices_to_remove.push(index),
Some(Ok(x)) => info!("control index {} has {} bytes readable", index, x),
_ => {}
}
}
}
}
// Sort in reverse so the highest indexes are removed first. This removal algorithm
// preserves correct indexes as each element is removed.
vm_control_indices_to_remove.sort_unstable_by(|a, b| b.cmp(a));
vm_control_indices_to_remove.dedup();
for index in vm_control_indices_to_remove {
// Delete the socket from the `poll_ctx` synchronously. Otherwise, the kernel will do
// this automatically when the FD inserted into the `poll_ctx` is closed after this
// if-block, but this removal can be deferred unpredictably. In some instances where the
// system is under heavy load, we can even get events returned by `poll_ctx` for an FD
// that has already been closed. Because the token associated with that spurious event
// now belongs to a different socket, the control loop will start to interact with
// sockets that might not be ready to use. This can cause incorrect hangup detection or
// blocking on a socket that will never be ready. See also: crbug.com/1019986
if let Some(socket) = control_sockets.get(index) {
poll_ctx.delete(socket).map_err(Error::PollContextDelete)?;
}
// This line implicitly drops the socket at `index` when it gets returned by
// `swap_remove`. After this line, the socket at `index` is not the one from
// `vm_control_indices_to_remove`. Because of this socket's change in index, we need to
// use `poll_ctx.modify` to change the associated index in its `Token::VmControl`.
control_sockets.swap_remove(index);
if let Some(socket) = control_sockets.get(index) {
poll_ctx
.modify(
socket,
WatchingEvents::empty().set_read(),
Token::VmControl { index },
)
.map_err(Error::PollContextAdd)?;
}
}
}
// VCPU threads MUST see the VmRunMode flag, otherwise they may re-enter the VM.
run_mode_arc.set_and_notify(VmRunMode::Exiting);
for handle in vcpu_handles {
match handle.kill(SIGRTMIN() + 0) {
Ok(_) => {
if let Err(e) = handle.join() {
error!("failed to join vcpu thread: {:?}", e);
}
}
Err(e) => error!("failed to kill vcpu thread: {}", e),
}
}
// Explicitly drop the VM structure here to allow the devices to clean up before the
// control sockets are closed when this function exits.
mem::drop(linux);
stdin_lock
.set_canon_mode()
.expect("failed to restore canonical mode for terminal");
Ok(())
}