// 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::cmp::max; use std::collections::{BTreeMap, VecDeque}; 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::ptr; use std::str; use std::sync::{Arc, Barrier}; use std::thread; use std::thread::JoinHandle; use std::time::Duration; use libc::{self, c_int, gid_t, uid_t}; use acpi_tables::sdt::SDT; #[cfg(feature = "gpu")] use devices::virtio::EventDevice; use devices::virtio::{self, Console, VirtioDevice}; use devices::{ self, Ac97Backend, Ac97Dev, Bus, HostBackendDeviceProvider, PciDevice, VfioContainer, VfioDevice, VfioPciDevice, VirtioPciDevice, XhciController, }; use io_jail::{self, Minijail}; use kvm::*; use msg_socket::{MsgError, MsgReceiver, MsgResult, MsgSender, MsgSocket}; use net_util::{Error as NetError, MacAddress, Tap}; 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, debug, 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, MemoryMappingArena, PollContext, PollToken, Protection, ScopedEvent, SignalFd, Terminal, TimerFd, WatchingEvents, SIGRTMIN, }; use vm_control::{ BalloonControlCommand, BalloonControlRequestSocket, BalloonControlResponseSocket, BalloonControlResult, DiskControlCommand, DiskControlRequestSocket, DiskControlResponseSocket, DiskControlResult, UsbControlSocket, VmControlResponseSocket, VmIrqRequest, VmIrqResponse, VmIrqResponseSocket, VmMemoryControlRequestSocket, VmMemoryControlResponseSocket, VmMemoryRequest, VmMemoryResponse, VmMsyncRequest, VmMsyncRequestSocket, VmMsyncResponse, VmMsyncResponseSocket, VmRequest, VmRunMode, }; use crate::{Config, DiskOption, Executable, SharedDir, SharedDirKind, TouchDeviceOption}; use arch::{ self, LinuxArch, RunnableLinuxVm, SerialHardware, SerialParameters, 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; #[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(::Error), ChownTpmStorage(sys_util::Error), CloneEventFd(sys_util::Error), CreateAc97(devices::PciDeviceError), CreateConsole(arch::serial::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(PathBuf, 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), MemoryTooLarge, NetDeviceNew(virtio::NetError), OpenAcpiTable(PathBuf, io::Error), 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), ReadMemAvailable(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), CreateAc97(e) => write!(f, "failed to create ac97 device: {}", e), CreateConsole(e) => write!(f, "failed to create console device: {}", 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(p, e) => write!(f, "failed to load disk image {}: {}", p.display(), 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), MemoryTooLarge => write!(f, "requested memory size too large"), NetDeviceNew(e) => write!(f, "failed to set up virtio networking: {}", e), OpenAcpiTable(p, e) => write!(f, "failed to open ACPI file {}: {}", p.display(), 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), ReadMemAvailable(e) => write!(f, "failed to read /proc/meminfo: {}", 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 for Error { fn from(err: io_jail::Error) -> Self { Error::IoJail(err) } } impl std::error::Error for Error {} type Result = std::result::Result; enum TaggedControlSocket { Vm(VmControlResponseSocket), VmMemory(VmMemoryControlResponseSocket), VmIrq(VmIrqResponseSocket), VmMsync(VmMsyncResponseSocket), } impl AsRef for TaggedControlSocket { fn as_ref(&self) -> &UnixSeqpacket { use self::TaggedControlSocket::*; match &self { Vm(ref socket) => socket.as_ref(), VmMemory(ref socket) => socket.as_ref(), VmIrq(ref socket) => socket.as_ref(), VmMsync(ref socket) => socket.as_ref(), } } } impl AsRawFd for TaggedControlSocket { fn as_raw_fd(&self) -> RawFd { self.as_ref().as_raw_fd() } } fn get_max_open_files() -> Result { let mut buf = mem::MaybeUninit::::zeroed(); // Safe because this will only modify `buf` and we check the return value. let res = unsafe { libc::prlimit64(0, libc::RLIMIT_NOFILE, ptr::null(), buf.as_mut_ptr()) }; if res == 0 { // Safe because the kernel guarantees that the struct is fully initialized. let limit = unsafe { buf.assume_init() }; Ok(limit.rlim_max) } else { Err(Error::GetMaxOpenFiles(io::Error::last_os_error())) } } struct SandboxConfig<'a> { limit_caps: bool, log_failures: bool, seccomp_policy: &'a Path, uid_map: Option<&'a str>, gid_map: Option<&'a str>, } fn create_base_minijail( root: &Path, r_limit: Option, config: Option<&SandboxConfig>, ) -> Result { // 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)?; if let Some(config) = config { j.namespace_pids(); j.namespace_user(); j.namespace_user_disable_setgroups(); if config.limit_caps { // Don't need any capabilities. j.use_caps(0); } if let Some(uid_map) = config.uid_map { j.uidmap(uid_map).map_err(Error::SettingUidMap)?; } if let Some(gid_map) = config.gid_map { j.gidmap(gid_map).map_err(Error::SettingGidMap)?; } // Run in a new mount namespace. j.namespace_vfs(); // Run in an empty network namespace. j.namespace_net(); // Don't allow the device to gain new privileges. j.no_new_privs(); // By default we'll prioritize using the pre-compiled .bpf over the .policy // file (the .bpf is expected to be compiled using "trap" as the failure // behavior instead of the default "kill" behavior). // Refer to the code comment for the "seccomp-log-failures" // command-line parameter for an explanation about why the |log_failures| // flag forces the use of .policy files (and the build-time alternative to // this run-time flag). let bpf_policy_file = config.seccomp_policy.with_extension("bpf"); if bpf_policy_file.exists() && !config.log_failures { j.parse_seccomp_program(&bpf_policy_file) .map_err(Error::DeviceJail)?; } else { // 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 config.log_failures { j.log_seccomp_filter_failures(); } j.parse_seccomp_filters(&config.seccomp_policy.with_extension("policy")) .map_err(Error::DeviceJail)?; } j.use_seccomp_filter(); // Don't do init setup. j.run_as_init(); } // Only pivot_root if we are not re-using the current root directory. if root != Path::new("/") { // It's safe to call `namespace_vfs` multiple times. j.namespace_vfs(); j.enter_pivot_root(root).map_err(Error::DevicePivotRoot)?; } // Most devices don't need to open many fds. let limit = if let Some(r) = r_limit { r } else { 1024u64 }; j.set_rlimit(libc::RLIMIT_NOFILE as i32, limit, limit) .map_err(Error::SettingMaxOpenFiles)?; Ok(j) } fn simple_jail(cfg: &Config, policy: &str) -> Result> { 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); let config = SandboxConfig { limit_caps: true, log_failures: cfg.seccomp_log_failures, seccomp_policy: &policy_path, uid_map: None, gid_map: None, }; Ok(Some(create_base_minijail(root_path, None, Some(&config))?)) } else { Ok(None) } } type DeviceResult = std::result::Result; 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(|e| Error::Disk(disk.path.to_path_buf(), e))? }; // 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, disk.block_size, Some(disk_device_socket), ) .map_err(Error::BlockDeviceNew)?; Ok(VirtioDeviceStub { dev: Box::new(dev), jail: simple_jail(&cfg, "block_device")?, }) } 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")?, }) } #[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")?; 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 = single_touch_spec .get_path() .into_unix_stream() .map_err(|e| { error!("failed configuring virtio single touch: {:?}", e); e })?; let (width, height) = single_touch_spec.get_size(); let dev = virtio::new_single_touch(socket, width, height).map_err(Error::InputDeviceNew)?; Ok(VirtioDeviceStub { dev: Box::new(dev), jail: simple_jail(&cfg, "input_device")?, }) } fn create_trackpad_device(cfg: &Config, trackpad_spec: &TouchDeviceOption) -> DeviceResult { let socket = trackpad_spec.get_path().into_unix_stream().map_err(|e| { error!("failed configuring virtio trackpad: {}", e); e })?; let (width, height) = trackpad_spec.get_size(); let dev = virtio::new_trackpad(socket, width, height).map_err(Error::InputDeviceNew)?; Ok(VirtioDeviceStub { dev: Box::new(dev), jail: simple_jail(&cfg, "input_device")?, }) } fn create_mouse_device(cfg: &Config, mouse_socket: T) -> DeviceResult { let socket = mouse_socket.into_unix_stream().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")?, }) } fn create_keyboard_device(cfg: &Config, keyboard_socket: T) -> DeviceResult { let socket = keyboard_socket.into_unix_stream().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")?, }) } 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")?, }) } 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")?, }) } 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 mut vq_pairs = cfg.net_vq_pairs.unwrap_or(1); let vcpu_count = cfg.vcpu_count.unwrap_or(1); if vcpu_count < vq_pairs as u32 { error!("net vq pairs must be smaller than vcpu count, fall back to single queue mode"); vq_pairs = 1; } let dev = virtio::Net::from(tap, vq_pairs).map_err(Error::NetDeviceNew)?; Ok(VirtioDeviceStub { dev: Box::new(dev), jail: simple_jail(&cfg, "net_device")?, }) } fn create_net_device( cfg: &Config, host_ip: Ipv4Addr, netmask: Ipv4Addr, mac_address: MacAddress, mem: &GuestMemory, ) -> DeviceResult { let mut vq_pairs = cfg.net_vq_pairs.unwrap_or(1); let vcpu_count = cfg.vcpu_count.unwrap_or(1); if vcpu_count < vq_pairs as u32 { error!("net vq pairs must be smaller than vcpu count, fall back to single queue mode"); vq_pairs = 1; } let dev = if cfg.vhost_net { let dev = virtio::vhost::Net::>::new(host_ip, netmask, mac_address, mem) .map_err(Error::VhostNetDeviceNew)?; Box::new(dev) as Box } else { let dev = virtio::Net::::new(host_ip, netmask, mac_address, vq_pairs) .map_err(Error::NetDeviceNew)?; Box::new(dev) as Box }; let policy = if cfg.vhost_net { "vhost_net_device" } else { "net_device" }; 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, wayland_socket_path: Option<&PathBuf>, x_display: Option, event_devices: Vec, ) -> DeviceResult { let jailed_wayland_path = Path::new("/wayland-0"); let mut display_backends = vec![ virtio::DisplayBackend::X(x_display), virtio::DisplayBackend::Stub, ]; if let Some(socket_path) = wayland_socket_path { 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, cfg.gpu_parameters.as_ref().unwrap(), event_devices, ); let jail = match simple_jail(&cfg, "gpu_device")? { 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, 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: VmMemoryControlRequestSocket, resource_bridge: Option, ) -> DeviceResult { let wayland_socket_dirs = cfg .wayland_socket_paths .iter() .map(|(_name, path)| path.parent()) .collect::>>() .ok_or(Error::InvalidWaylandPath)?; let dev = virtio::Wl::new(cfg.wayland_socket_paths.clone(), socket, resource_bridge) .map_err(Error::WaylandDeviceNew)?; let jail = match simple_jail(&cfg, "wl_device")? { 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. for dir in &wayland_socket_dirs { jail.mount_bind(dir, dir, true)?; } add_crosvm_user_to_jail(&mut jail, "Wayland")?; Some(jail) } None => None, }; Ok(VirtioDeviceStub { dev: Box::new(dev), jail, }) } #[cfg(any(feature = "video-decoder", feature = "video-encoder"))] fn create_video_device( cfg: &Config, typ: devices::virtio::VideoDeviceType, resource_bridge: virtio::resource_bridge::ResourceRequestSocket, ) -> DeviceResult { let jail = match simple_jail(&cfg, "video_device")? { Some(mut jail) => { match typ { devices::virtio::VideoDeviceType::Decoder => { add_crosvm_user_to_jail(&mut jail, "video-decoder")? } devices::virtio::VideoDeviceType::Encoder => { add_crosvm_user_to_jail(&mut jail, "video-encoder")? } }; // Create a tmpfs in the device's root directory so that we can bind mount files. jail.mount_with_data( Path::new("none"), Path::new("/"), "tmpfs", (libc::MS_NOSUID | libc::MS_NODEV | libc::MS_NOEXEC) as usize, "size=67108864", )?; // Render node for libvda. let dev_dri_path = Path::new("/dev/dri/renderD128"); jail.mount_bind(dev_dri_path, dev_dri_path, false)?; // Device nodes required by libchrome which establishes Mojo connection in libvda. let dev_urandom_path = Path::new("/dev/urandom"); jail.mount_bind(dev_urandom_path, dev_urandom_path, false)?; let system_bus_socket_path = Path::new("/run/dbus/system_bus_socket"); jail.mount_bind(system_bus_socket_path, system_bus_socket_path, true)?; Some(jail) } None => None, }; Ok(VirtioDeviceStub { dev: Box::new(devices::virtio::VideoDevice::new( typ, Some(resource_bridge), )), jail, }) } #[cfg(any(feature = "video-decoder", feature = "video-encoder"))] fn register_video_device( devs: &mut Vec, resource_bridges: &mut Vec, cfg: &Config, typ: devices::virtio::VideoDeviceType, ) -> std::result::Result<(), Error> { let (video_socket, gpu_socket) = virtio::resource_bridge::pair().map_err(Error::CreateSocket)?; resource_bridges.push(gpu_socket); devs.push(create_video_device(cfg, typ, video_socket)?); Ok(()) } 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")?, }) } fn create_fs_device( cfg: &Config, uid_map: &str, gid_map: &str, src: &Path, tag: &str, fs_cfg: virtio::fs::passthrough::Config, ) -> DeviceResult { let max_open_files = get_max_open_files()?; let j = if cfg.sandbox { let seccomp_policy = cfg.seccomp_policy_dir.join("fs_device"); let config = SandboxConfig { limit_caps: false, uid_map: Some(uid_map), gid_map: Some(gid_map), log_failures: cfg.seccomp_log_failures, seccomp_policy: &seccomp_policy, }; let mut jail = create_base_minijail(src, Some(max_open_files), Some(&config))?; // We want bind mounts from the parent namespaces to propagate into the fs device's // namespace. jail.set_remount_mode(libc::MS_SLAVE); jail } else { create_base_minijail(src, Some(max_open_files), None)? }; // 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, uid_map: &str, gid_map: &str, src: &Path, tag: &str, ) -> DeviceResult { let max_open_files = get_max_open_files()?; let (jail, root) = if cfg.sandbox { let seccomp_policy = cfg.seccomp_policy_dir.join("9p_device"); let config = SandboxConfig { limit_caps: false, uid_map: Some(uid_map), gid_map: Some(gid_map), log_failures: cfg.seccomp_log_failures, seccomp_policy: &seccomp_policy, }; let mut jail = create_base_minijail(src, Some(max_open_files), Some(&config))?; // We want bind mounts from the parent namespaces to propagate into the 9p server's // namespace. jail.set_remount_mode(libc::MS_SLAVE); // The shared directory becomes the root of the device's file system. let root = Path::new("/"); (Some(jail), root) } else { // There's no mount namespace 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, pmem_device_socket: VmMsyncRequestSocket, ) -> DeviceResult { let fd = OpenOptions::new() .read(true) .write(!disk.read_only) .open(&disk.path) .map_err(|e| Error::Disk(disk.path.to_path_buf(), e))?; let arena_size = { let metadata = std::fs::metadata(&disk.path).map_err(|e| Error::Disk(disk.path.to_path_buf(), e))?; let disk_len = metadata.len(); // Linux requires pmem region sizes to be 2 MiB aligned. Linux will fill any partial page // at the end of an mmap'd file and won't write back beyond the actual file length, but if // we just align the size of the file to 2 MiB then access beyond the last page of the // mapped file will generate SIGBUS. So use a memory mapping arena that will provide // padding up to 2 MiB. let alignment = 2 * 1024 * 1024; let align_adjust = if disk_len % alignment != 0 { alignment - (disk_len % alignment) } else { 0 }; disk_len .checked_add(align_adjust) .ok_or(Error::PmemDeviceImageTooBig)? }; let protection = { if disk.read_only { Protection::read() } else { Protection::read_write() } }; let arena = { // Conversion from u64 to usize may fail on 32bit system. let arena_size = usize::try_from(arena_size).map_err(|_| Error::PmemDeviceImageTooBig)?; let mut arena = MemoryMappingArena::new(arena_size).map_err(Error::ReservePmemMemory)?; arena .add_fd_offset_protection(0, arena_size, &fd, 0, protection) .map_err(Error::ReservePmemMemory)?; arena }; let mapping_address = resources .mmio_allocator(MmioType::High) .allocate_with_align( arena_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)?; let slot = vm .add_memory_region( GuestAddress(mapping_address), Box::new(arena), /* read_only = */ disk.read_only, /* log_dirty_pages = */ false, ) .map_err(Error::AddPmemDeviceMemory)?; let dev = virtio::Pmem::new( fd, GuestAddress(mapping_address), slot, arena_size, Some(pmem_device_socket), ) .map_err(Error::PmemDeviceNew)?; Ok(VirtioDeviceStub { dev: Box::new(dev) as Box, jail: simple_jail(&cfg, "pmem_device")?, }) } fn create_console_device(cfg: &Config, param: &SerialParameters) -> DeviceResult { let mut keep_fds = Vec::new(); let evt = EventFd::new().map_err(Error::CreateEventFd)?; let dev = param .create_serial_device::(&evt, &mut keep_fds) .map_err(Error::CreateConsole)?; Ok(VirtioDeviceStub { dev: Box::new(dev), jail: simple_jail(&cfg, "serial")?, // TODO(dverkamp): use a separate policy for console? }) } // 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, pmem_device_sockets: &mut Vec, ) -> DeviceResult> { let mut devs = Vec::new(); for (_, param) in cfg .serial_parameters .iter() .filter(|(_k, v)| v.hardware == SerialHardware::VirtioConsole) { let dev = create_console_device(cfg, param)?; devs.push(dev); } 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() { let pmem_device_socket = pmem_device_sockets.remove(0); devs.push(create_pmem_device( cfg, vm, resources, pmem_disk, index, pmem_device_socket, )?); } 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::::new(); if !cfg.wayland_socket_paths.is_empty() { #[cfg_attr(not(feature = "gpu"), allow(unused_mut))] let mut wl_resource_bridge = None::; #[cfg(feature = "gpu")] { if cfg.gpu_parameters.is_some() { 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_device_socket, wl_resource_bridge, )?); } #[cfg(feature = "video-decoder")] { if cfg.video_dec { register_video_device( &mut devs, &mut resource_bridges, cfg, devices::virtio::VideoDeviceType::Decoder, )?; } } #[cfg(feature = "video-encoder")] { if cfg.video_enc { register_video_device( &mut devs, &mut resource_bridges, cfg, devices::virtio::VideoDeviceType::Encoder, )?; } } #[cfg(feature = "gpu")] { if let Some(gpu_parameters) = &cfg.gpu_parameters { let mut event_devices = Vec::new(); if cfg.display_window_mouse { let (event_device_socket, virtio_dev_socket) = UnixStream::pair().map_err(Error::CreateSocket)?; let (single_touch_width, single_touch_height) = cfg .virtio_single_touch .as_ref() .map(|single_touch_spec| single_touch_spec.get_size()) .unwrap_or((gpu_parameters.display_width, gpu_parameters.display_height)); let dev = virtio::new_single_touch( virtio_dev_socket, single_touch_width, single_touch_height, ) .map_err(Error::InputDeviceNew)?; devs.push(VirtioDeviceStub { dev: Box::new(dev), jail: simple_jail(&cfg, "input_device")?, }); event_devices.push(EventDevice::touchscreen(event_device_socket)); } if cfg.display_window_keyboard { let (event_device_socket, virtio_dev_socket) = UnixStream::pair().map_err(Error::CreateSocket)?; let dev = virtio::new_keyboard(virtio_dev_socket).map_err(Error::InputDeviceNew)?; devs.push(VirtioDeviceStub { dev: Box::new(dev), jail: simple_jail(&cfg, "input_device")?, }); event_devices.push(EventDevice::keyboard(event_device_socket)); } devs.push(create_gpu_device( cfg, _exit_evt, gpu_device_socket, resource_bridges, // Use the unnamed socket for GPU display screens. cfg.wayland_socket_paths.get(""), cfg.x_display.clone(), event_devices, )?); } } 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, uid_map, gid_map, 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, wayland_device_socket: VmMemoryControlRequestSocket, gpu_device_socket: VmMemoryControlRequestSocket, balloon_device_socket: BalloonControlResponseSocket, disk_device_sockets: &mut Vec, pmem_device_sockets: &mut Vec, usb_provider: HostBackendDeviceProvider, ) -> DeviceResult, Option)>> { let stubs = create_virtio_devices( &cfg, mem, vm, resources, exit_evt, wayland_device_socket, gpu_device_socket, balloon_device_socket, disk_device_sockets, pmem_device_sockets, )?; let mut pci_devices = Vec::new(); for stub in stubs { let (msi_host_socket, msi_device_socket) = msg_socket::pair::().map_err(Error::CreateSocket)?; control_sockets.push(TaggedControlSocket::VmIrq(msi_host_socket)); let dev = VirtioPciDevice::new(mem.clone(), stub.dev, msi_device_socket) .map_err(Error::VirtioPciDev)?; let dev = Box::new(dev) as Box; pci_devices.push((dev, stub.jail)); } for ac97_param in &cfg.ac97_parameters { let dev = Ac97Dev::try_new(mem.clone(), ac97_param.clone()).map_err(Error::CreateAc97)?; let policy = match ac97_param.backend { Ac97Backend::CRAS => "cras_audio_device", Ac97Backend::NULL => "null_audio_device", }; pci_devices.push((Box::new(dev), simple_jail(&cfg, &policy)?)); } // Create xhci controller. let usb_controller = Box::new(XhciController::new(mem.clone(), usb_provider)); pci_devices.push((usb_controller, simple_jail(&cfg, "xhci")?)); if !cfg.vfio.is_empty() { let vfio_container = Arc::new(Mutex::new( VfioContainer::new().map_err(Error::CreateVfioDevice)?, )); for vfio_path in &cfg.vfio { // create one Irq and Mem request socket for each vfio device let (vfio_host_socket_irq, vfio_device_socket_irq) = msg_socket::pair::().map_err(Error::CreateSocket)?; control_sockets.push(TaggedControlSocket::VmIrq(vfio_host_socket_irq)); let (vfio_host_socket_mem, vfio_device_socket_mem) = msg_socket::pair::() .map_err(Error::CreateSocket)?; control_sockets.push(TaggedControlSocket::VmMemory(vfio_host_socket_mem)); let vfiodevice = VfioDevice::new(vfio_path.as_path(), vm, mem, vfio_container.clone()) .map_err(Error::CreateVfioDevice)?; let vfiopcidevice = Box::new(VfioPciDevice::new( vfiodevice, vfio_device_socket_irq, vfio_device_socket_mem, )); pci_devices.push((vfiopcidevice, simple_jail(&cfg, "vfio_device")?)); } } 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 { 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 { 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::().ok()) .ok_or(Error::InvalidFdPath)?; validate_raw_fd(raw_fd).map_err(Error::ValidateRawFd) } trait IntoUnixStream { fn into_unix_stream(self) -> Result; } impl<'a> IntoUnixStream for &'a Path { fn into_unix_stream(self) -> Result { if self.parent() == Some(Path::new("/proc/self/fd")) { // Safe because we will validate |raw_fd|. unsafe { Ok(UnixStream::from_raw_fd(raw_fd_from_path(self)?)) } } else { UnixStream::connect(self).map_err(Error::InputEventsOpen) } } } impl<'a> IntoUnixStream for &'a PathBuf { fn into_unix_stream(self) -> Result { self.as_path().into_unix_stream() } } impl IntoUnixStream for UnixStream { fn into_unix_stream(self) -> Result { Ok(self) } } 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, cvar: Condvar, } impl VcpuRunMode { fn set_and_notify(&self, new_mode: VmRunMode) { *self.mtx.lock() = new_mode; self.cvar.notify_all(); } } // Converts a vcpu into a runnable vcpu if possible. On failure, returns `None`. fn runnable_vcpu(vcpu: Vcpu, use_kvm_signals: bool, cpu_id: u32) -> Option { 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 ); return None; } } Err(e) => { error!("Failed to retrieve signal mask for vcpu {} : {}", cpu_id, e); return None; } }; } match vcpu.to_runnable(Some(SIGRTMIN() + 0)) { Ok(v) => Some(v), Err(e) => { error!("Failed to set thread id for vcpu {} : {}", cpu_id, e); None } } } #[cfg(any(target_arch = "x86", target_arch = "x86_64"))] fn inject_interrupt(pic: &Arc>, vcpu: &RunnableVcpu) { let mut pic = pic.lock(); if pic.interrupt_requested() && vcpu.ready_for_interrupt() { if let Some(vector) = pic.get_external_interrupt() { if let Err(e) = vcpu.interrupt(vector as u32) { error!("PIC: failed to inject interrupt to vCPU0: {}", e); } } // The second interrupt request should be handled immediately, so ask // vCPU to exit as soon as possible. if pic.interrupt_requested() { vcpu.request_interrupt_window(); } } } #[cfg(any(target_arch = "arm", target_arch = "aarch64"))] fn inject_interrupt(pic: &Arc>, vcpu: &RunnableVcpu) {} fn run_vcpu( vcpu: Vcpu, cpu_id: u32, vcpu_affinity: Vec, start_barrier: Arc, io_bus: devices::Bus, mmio_bus: devices::Bus, split_irqchip: Option<(Arc>, Arc>)>, exit_evt: EventFd, requires_kvmclock_ctrl: bool, run_mode_arc: Arc, use_kvm_signals: bool, ) -> Result> { thread::Builder::new() .name(format!("crosvm_vcpu{}", cpu_id)) .spawn(move || { // The VCPU thread must trigger the `exit_evt` in all paths, and a `ScopedEvent`'s Drop // implementation accomplishes that. let _scoped_exit_evt = ScopedEvent::from(exit_evt); if !vcpu_affinity.is_empty() { if let Err(e) = set_cpu_affinity(vcpu_affinity) { error!("Failed to set CPU affinity: {}", e); } } let vcpu = runnable_vcpu(vcpu, use_kvm_signals, cpu_id); start_barrier.wait(); if let Some(vcpu) = vcpu { 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::IoapicEoi{vector}) => { if let Some((_, ioapic)) = &split_irqchip { ioapic.lock().end_of_interrupt(vector); } else { panic!("userspace ioapic not found in split irqchip mode, should be impossible."); } }, Ok(VcpuExit::Hlt) => break, Ok(VcpuExit::Shutdown) => break, Ok(VcpuExit::FailEntry { hardware_entry_failure_reason, }) => { error!("vcpu hw run failure: {:#x}", hardware_entry_failure_reason); 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 => return, } // 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); } } if cpu_id != 0 { continue; } if let Some((pic, _)) = &split_irqchip { inject_interrupt(pic, &vcpu); } } } }) .map_err(Error::SpawnVcpu) } // Reads the contents of a file and converts the space-separated fields into a Vec of i64s. // Returns an error if any of the fields fail to parse. fn file_fields_to_i64>(path: P) -> io::Result> { 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::() .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e)) }) .collect() } // Reads the contents of a file and converts them into a i64, and if there // are multiple fields it only returns the first one. fn file_to_i64>(path: P) -> io::Result { file_fields_to_i64(path)? .into_iter() .next() .ok_or_else(|| io::Error::new(io::ErrorKind::InvalidData, "empty file")) } /// Returns a boolean indicating whether the VM should be exited. fn do_vm_request( request: VmRequest, device_socket: Option<&UnixSeqpacket>, control_socket: &VmControlResponseSocket, run_mode_arc: &Arc, vcpu_handles: &mut Vec>, io_bus: &mut Bus, ) -> MsgResult { let mut run_mode_opt = None; let response = request.execute(&mut run_mode_opt, device_socket); control_socket.send(&response)?; if let Some(run_mode) = run_mode_opt { info!("control socket changed run mode to {}", run_mode); match run_mode { VmRunMode::Exiting => Ok(true), VmRunMode::Running => { if let VmRunMode::Suspending = *run_mode_arc.mtx.lock() { io_bus.notify_resume(); } run_mode_arc.set_and_notify(VmRunMode::Running); for handle in vcpu_handles { let _ = handle.kill(SIGRTMIN() + 0); } Ok(false) } other => { run_mode_arc.set_and_notify(other); for handle in vcpu_handles { let _ = handle.kill(SIGRTMIN() + 0); } Ok(false) } } } else { Ok(false) } } 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) .checked_mul(1024 * 1024) .ok_or(Error::MemoryTooLarge)?, 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))?, pstore: cfg.pstore.clone(), initrd_image, extra_kernel_params: cfg.params.clone(), wayland_dmabuf: cfg.wayland_dmabuf, acpi_sdts: cfg .acpi_tables .iter() .map(|path| SDT::from_file(path).map_err(|e| Error::OpenAcpiTable(path.clone(), e))) .collect::>>()?, }; 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::().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::() .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::() .map_err(Error::CreateSocket)?; disk_host_sockets.push(disk_host_socket); disk_device_sockets.push(disk_device_socket); } let mut pmem_device_sockets = Vec::new(); let pmem_count = cfg.pmem_devices.len(); for _ in 0..pmem_count { let (pmem_host_socket, pmem_device_socket) = msg_socket::pair::().map_err(Error::CreateSocket)?; pmem_device_sockets.push(pmem_device_socket); control_sockets.push(TaggedControlSocket::VmMsync(pmem_host_socket)); } let (gpu_host_socket, gpu_device_socket) = msg_socket::pair::().map_err(Error::CreateSocket)?; control_sockets.push(TaggedControlSocket::VmMemory(gpu_host_socket)); let (ioapic_host_socket, ioapic_device_socket) = msg_socket::pair::().map_err(Error::CreateSocket)?; control_sockets.push(TaggedControlSocket::VmIrq(ioapic_host_socket)); let sandbox = cfg.sandbox; let linux = Arch::build_vm( components, cfg.split_irqchip, ioapic_device_socket, &cfg.serial_parameters, simple_jail(&cfg, "serial")?, |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, &mut pmem_device_sockets, usb_provider, ) }, ) .map_err(Error::BuildVm)?; run_control( linux, control_server_socket, control_sockets, balloon_host_socket, &disk_host_sockets, usb_control_socket, sigchld_fd, sandbox, ) } fn run_control( mut linux: RunnableLinuxVm, control_server_socket: Option, mut control_sockets: Vec, balloon_host_socket: BalloonControlRequestSocket, disk_host_sockets: &[DiskControlRequestSocket], usb_control_socket: UsbControlSocket, sigchld_fd: SignalFd, sandbox: bool, ) -> Result<()> { const LOWMEM_AVAILABLE: &str = "/sys/kernel/mm/chromeos-low_mem/available"; #[derive(Debug, PollToken)] enum Token { Exit, Suspend, ChildSignal, IrqFd { gsi: usize }, BalanceMemory, BalloonResult, VmControlServer, VmControl { index: usize }, DeviceReady { sock_fd: RawFd }, } stdin() .set_raw_mode() .expect("failed to set terminal raw mode"); let poll_ctx = PollContext::build_with(&[ (&linux.exit_evt, Token::Exit), (&linux.suspend_evt, Token::Suspend), (&sigchld_fd, Token::ChildSignal), ]) .map_err(Error::PollContextAdd)?; 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)?; } if let Some(gsi_relay) = &linux.gsi_relay { for (gsi, evt) in gsi_relay.irqfd.iter().enumerate() { if let Some(evt) = evt { poll_ctx .add(evt, Token::IrqFd { gsi }) .map_err(Error::PollContextAdd)?; } } } // Balance available memory between guest and host every second. let balancemem_timer = TimerFd::new().map_err(Error::CreateTimerFd)?; if Path::new(LOWMEM_AVAILABLE).exists() { // Create timer request balloon stats every 1s. poll_ctx .add(&balancemem_timer, Token::BalanceMemory) .map_err(Error::PollContextAdd)?; let balancemem_dur = Duration::from_secs(1); let balancemem_int = Duration::from_secs(1); balancemem_timer .reset(balancemem_dur, Some(balancemem_int)) .map_err(Error::ResetTimerFd)?; // Listen for balloon statistics from the guest so we can balance. poll_ctx .add(&balloon_host_socket, Token::BalloonResult) .map_err(Error::PollContextAdd)?; } else { warn!("Unable to open low mem available, maybe not a chrome os kernel"); } 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.split_irqchip.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(); struct QueuedDeviceReq { request: VmRequest, control_sock_index: usize, } /// A device can either be waiting, or ready. /// /// If it's waiting, we queue up events to send to it once it's ready. We can't just send the /// requests straight away and let them sit on the socket until the device comes up, because we /// want to syncronously wait for a response after sending. If the device hasn't been activated /// when we do this, we'd sit waiting for a response forever and never activate the device. enum DeviceStatus<'a> { Waiting(&'a UnixSeqpacket, VecDeque), Ready, } let mut queued_device_reqs = BTreeMap::::new(); // Each socket will send a ready message when it's ready to receive requests. Add the sockets // to the event loop, so that when they become ready, we can process their queues. After the // initial queue is processed, the device becomes ready, and the socket is removed from the // event loop. for socket in disk_host_sockets.iter().map(AsRef::as_ref) { let token = Token::DeviceReady { sock_fd: socket.as_raw_fd(), }; poll_ctx.add(socket, token).map_err(Error::PollContextAdd)?; let status = DeviceStatus::Waiting(socket, VecDeque::new()); queued_device_reqs.insert(socket.as_raw_fd(), status); } let mut ioapic_delayed = Vec::::default(); 'poll: loop { let events = { match poll_ctx.wait() { Ok(v) => v, Err(e) => { error!("failed to poll: {}", e); break; } } }; ioapic_delayed.retain(|&gsi| { if let Some((_, ioapic)) = &linux.split_irqchip { if let Ok(mut ioapic) = ioapic.try_lock() { // The unwrap will never fail because gsi_relay is Some iff split_irqchip is // Some. if linux.gsi_relay.as_ref().unwrap().irqfd_resample[gsi].is_some() { ioapic.service_irq(gsi, true); } else { ioapic.service_irq(gsi, true); ioapic.service_irq(gsi, false); } false } else { true } } else { true } }); 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::Suspend => { info!("VM requested suspend"); linux.suspend_evt.read().unwrap(); run_mode_arc.set_and_notify(VmRunMode::Suspending); for handle in &vcpu_handles { let _ = handle.kill(SIGRTMIN() + 0); } } 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::IrqFd { gsi } => { if let Some((pic, ioapic)) = &linux.split_irqchip { // This will never fail because gsi_relay is Some iff split_irqchip is // Some. let gsi_relay = linux.gsi_relay.as_ref().unwrap(); if let Some(eventfd) = &gsi_relay.irqfd[gsi] { eventfd.read().unwrap(); } else { warn!( "irqfd {} not found in GSI relay, should be impossible.", gsi ); } let mut pic = pic.lock(); if gsi_relay.irqfd_resample[gsi].is_some() { pic.service_irq(gsi as u8, true); } else { pic.service_irq(gsi as u8, true); pic.service_irq(gsi as u8, false); } if let Err(e) = vcpu_handles[0].kill(SIGRTMIN() + 0) { warn!("PIC: failed to kick vCPU0: {}", e); } // When IOAPIC is configuring its redirection table, we should first // process its AddMsiRoute request, otherwise we would deadlock. if let Ok(mut ioapic) = ioapic.try_lock() { if gsi_relay.irqfd_resample[gsi].is_some() { ioapic.service_irq(gsi, true); } else { ioapic.service_irq(gsi, true); ioapic.service_irq(gsi, false); } } else { ioapic_delayed.push(gsi); } } else { panic!("split irqchip not found, should be impossible."); } } Token::BalanceMemory => { balancemem_timer.wait().map_err(Error::TimerFd)?; let command = BalloonControlCommand::Stats {}; if let Err(e) = balloon_host_socket.send(&command) { warn!("failed to send stats request to balloon device: {}", e); } } Token::BalloonResult => { match balloon_host_socket.recv() { Ok(BalloonControlResult::Stats { stats, balloon_actual: balloon_actual_u, }) => { // Available memory is reported in MB, and we need bytes. let host_available = file_to_i64(LOWMEM_AVAILABLE) .map_err(Error::ReadMemAvailable)? << 20; let guest_available_u = if let Some(available) = stats.available_memory { available } else { warn!("guest available_memory stat is missing"); continue; }; if guest_available_u > i64::max_value() as u64 { warn!("guest available memory is too large"); continue; } if balloon_actual_u > i64::max_value() as u64 { warn!("actual balloon size is too large"); continue; } // Guest and host available memory is balanced equally. const GUEST_SHARE: i64 = 1; const HOST_SHARE: i64 = 1; // Tell the guest to change the balloon size if the // target balloon size is more than 5% different // from the current balloon size. const RESIZE_PERCENT: i64 = 5; let balloon_actual = balloon_actual_u as i64; let guest_available = guest_available_u as i64; // Compute how much memory the guest should have // available after we rebalance. let guest_available_target = (GUEST_SHARE * (guest_available + host_available)) / (GUEST_SHARE + HOST_SHARE); let guest_available_delta = guest_available_target - guest_available; // How much do we have to change the balloon to // balance. let balloon_target = max(balloon_actual - guest_available_delta, 0); // Compute the change in balloon size in percent. // If the balloon size is 0, use 1 so we don't // overflow from the infinity % increase. let balloon_change_percent = (balloon_actual - balloon_target).abs() * 100 / max(balloon_actual, 1); if balloon_change_percent >= RESIZE_PERCENT { let command = BalloonControlCommand::Adjust { num_bytes: balloon_target as u64, }; if let Err(e) = balloon_host_socket.send(&command) { warn!("failed to send memory value to balloon device: {}", e); } } } Err(e) => { error!("failed to recv BalloonControlResult: {}", e); } }; } 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 device_socket = request.socket( &balloon_host_socket, &disk_host_sockets, &usb_control_socket, ); match device_socket.map(|s| { queued_device_reqs.get_mut(&s.as_raw_fd()).unwrap() }) { None | Some(DeviceStatus::Ready) => { match do_vm_request( request, device_socket, socket, &run_mode_arc, &mut vcpu_handles, &mut linux.io_bus, ) { Ok(true) => break 'poll, Ok(false) => {} Err(e) => { error!("failed to handle VmRequest: {}", e); continue 'poll; } } } Some(DeviceStatus::Waiting(_, queue)) => { debug!( "Device {} not yet ready. Queueing request.", device_socket.unwrap().as_raw_fd() ); queue.push_back(QueuedDeviceReq { request, control_sock_index: index, }); } } } Err(e) => { if let MsgError::RecvZero = 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::RecvZero = 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::RecvZero = e { vm_control_indices_to_remove.push(index); } else { error!("failed to recv VmIrqRequest: {}", e); } } }, TaggedControlSocket::VmMsync(socket) => match socket.recv() { Ok(request) => { let response = request.execute(&mut linux.vm); if let Err(e) = socket.send(&response) { error!("failed to send VmMsyncResponse: {}", e); } } Err(e) => { if let MsgError::BadRecvSize { actual: 0, .. } = e { vm_control_indices_to_remove.push(index); } else { error!("failed to recv VmMsyncRequest: {}", e); } } }, } } } Token::DeviceReady { sock_fd } => { if let Some(DeviceStatus::Waiting(device_sock, mut queue)) = queued_device_reqs.remove(&sock_fd) { debug!( "Device {} is ready. Processing its queue of {} item(s).", sock_fd, queue.len() ); // Deal with the message sent to indicate readiness. Its contents don't matter. if let Err(e) = device_sock.recv(&mut []) { error!( "Failed to recv ready notification from device socket: {}", e ); continue 'poll; } while let Some(QueuedDeviceReq { request, control_sock_index, }) = queue.pop_front() { let control_sock = match control_sockets.get(control_sock_index) { Some(TaggedControlSocket::Vm(s)) => s, _ => unreachable!(), }; match do_vm_request( request, Some(device_sock), control_sock, &run_mode_arc, &mut vcpu_handles, &mut linux.io_bus, ) { Ok(true) => break 'poll, Ok(false) => {} Err(e) => { error!("failed to handle VmRequest: {}", e); continue 'poll; } } } if let Err(e) = poll_ctx.delete(device_sock) { error!("failed to delete poll token: {}", e); } } else { error!("Received ready notification for a device that isn't waiting"); } queued_device_reqs.insert(sock_fd, DeviceStatus::Ready); } } } for event in events.iter_hungup() { match event.token() { Token::Exit => {} Token::Suspend => {} Token::ChildSignal => {} Token::IrqFd { gsi: _ } => {} Token::BalanceMemory => {} Token::BalloonResult => {} 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), _ => {} } } Token::DeviceReady { .. } => {} } } // 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() .set_canon_mode() .expect("failed to restore canonical mode for terminal"); Ok(()) }