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Diffstat (limited to 'runsc/boot/loader.go')
-rw-r--r--runsc/boot/loader.go292
1 files changed, 203 insertions, 89 deletions
diff --git a/runsc/boot/loader.go b/runsc/boot/loader.go
index 0c0eba99e..f6ea4c102 100644
--- a/runsc/boot/loader.go
+++ b/runsc/boot/loader.go
@@ -20,7 +20,6 @@ import (
mrand "math/rand"
"os"
"runtime"
- "sync"
"sync/atomic"
"syscall"
gtime "time"
@@ -36,6 +35,8 @@ import (
"gvisor.dev/gvisor/pkg/sentry/control"
"gvisor.dev/gvisor/pkg/sentry/fs"
"gvisor.dev/gvisor/pkg/sentry/fs/host"
+ "gvisor.dev/gvisor/pkg/sentry/fs/user"
+ vfs2host "gvisor.dev/gvisor/pkg/sentry/fsimpl/host"
"gvisor.dev/gvisor/pkg/sentry/inet"
"gvisor.dev/gvisor/pkg/sentry/kernel"
"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
@@ -43,11 +44,14 @@ import (
"gvisor.dev/gvisor/pkg/sentry/pgalloc"
"gvisor.dev/gvisor/pkg/sentry/platform"
"gvisor.dev/gvisor/pkg/sentry/sighandling"
- slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux"
+ "gvisor.dev/gvisor/pkg/sentry/syscalls/linux/vfs2"
"gvisor.dev/gvisor/pkg/sentry/time"
"gvisor.dev/gvisor/pkg/sentry/usage"
+ "gvisor.dev/gvisor/pkg/sentry/vfs"
"gvisor.dev/gvisor/pkg/sentry/watchdog"
+ "gvisor.dev/gvisor/pkg/sync"
"gvisor.dev/gvisor/pkg/tcpip"
+ "gvisor.dev/gvisor/pkg/tcpip/link/loopback"
"gvisor.dev/gvisor/pkg/tcpip/link/sniffer"
"gvisor.dev/gvisor/pkg/tcpip/network/arp"
"gvisor.dev/gvisor/pkg/tcpip/network/ipv4"
@@ -59,16 +63,20 @@ import (
"gvisor.dev/gvisor/pkg/tcpip/transport/udp"
"gvisor.dev/gvisor/runsc/boot/filter"
_ "gvisor.dev/gvisor/runsc/boot/platforms" // register all platforms.
+ "gvisor.dev/gvisor/runsc/boot/pprof"
"gvisor.dev/gvisor/runsc/specutils"
// Include supported socket providers.
"gvisor.dev/gvisor/pkg/sentry/socket/hostinet"
_ "gvisor.dev/gvisor/pkg/sentry/socket/netlink"
_ "gvisor.dev/gvisor/pkg/sentry/socket/netlink/route"
+ _ "gvisor.dev/gvisor/pkg/sentry/socket/netlink/uevent"
"gvisor.dev/gvisor/pkg/sentry/socket/netstack"
_ "gvisor.dev/gvisor/pkg/sentry/socket/unix"
)
+var syscallTable *kernel.SyscallTable
+
// Loader keeps state needed to start the kernel and run the container..
type Loader struct {
// k is the kernel.
@@ -93,10 +101,6 @@ type Loader struct {
// spec is the base configuration for the root container.
spec *specs.Spec
- // startSignalForwarding enables forwarding of signals to the sandboxed
- // container. It should be called after the init process is loaded.
- startSignalForwarding func() func()
-
// stopSignalForwarding disables forwarding of signals to the sandboxed
// container. It should be called when a sandbox is destroyed.
stopSignalForwarding func()
@@ -146,9 +150,6 @@ type execProcess struct {
func init() {
// Initialize the random number generator.
mrand.Seed(gtime.Now().UnixNano())
-
- // Register the global syscall table.
- kernel.RegisterSyscallTable(slinux.AMD64)
}
// Args are the arguments for New().
@@ -159,13 +160,17 @@ type Args struct {
Spec *specs.Spec
// Conf is the system configuration.
Conf *Config
- // ControllerFD is the FD to the URPC controller.
+ // ControllerFD is the FD to the URPC controller. The Loader takes ownership
+ // of this FD and may close it at any time.
ControllerFD int
- // Device is an optional argument that is passed to the platform.
+ // Device is an optional argument that is passed to the platform. The Loader
+ // takes ownership of this file and may close it at any time.
Device *os.File
- // GoferFDs is an array of FDs used to connect with the Gofer.
+ // GoferFDs is an array of FDs used to connect with the Gofer. The Loader
+ // takes ownership of these FDs and may close them at any time.
GoferFDs []int
- // StdioFDs is the stdio for the application.
+ // StdioFDs is the stdio for the application. The Loader takes ownership of
+ // these FDs and may close them at any time.
StdioFDs []int
// Console is set to true if using TTY.
Console bool
@@ -178,6 +183,9 @@ type Args struct {
UserLogFD int
}
+// make sure stdioFDs are always the same on initial start and on restore
+const startingStdioFD = 64
+
// New initializes a new kernel loader configured by spec.
// New also handles setting up a kernel for restoring a container.
func New(args Args) (*Loader, error) {
@@ -191,6 +199,14 @@ func New(args Args) (*Loader, error) {
return nil, fmt.Errorf("setting up memory usage: %v", err)
}
+ // Patch the syscall table.
+ kernel.VFS2Enabled = args.Conf.VFS2
+ if kernel.VFS2Enabled {
+ vfs2.Override(syscallTable.Table)
+ }
+
+ kernel.RegisterSyscallTable(syscallTable)
+
// Create kernel and platform.
p, err := createPlatform(args.Conf, args.Device)
if err != nil {
@@ -228,11 +244,8 @@ func New(args Args) (*Loader, error) {
return nil, fmt.Errorf("enabling strace: %v", err)
}
- // Create an empty network stack because the network namespace may be empty at
- // this point. Netns is configured before Run() is called. Netstack is
- // configured using a control uRPC message. Host network is configured inside
- // Run().
- networkStack, err := newEmptyNetworkStack(args.Conf, k)
+ // Create root network namespace/stack.
+ netns, err := newRootNetworkNamespace(args.Conf, k, k)
if err != nil {
return nil, fmt.Errorf("creating network: %v", err)
}
@@ -275,7 +288,7 @@ func New(args Args) (*Loader, error) {
FeatureSet: cpuid.HostFeatureSet(),
Timekeeper: tk,
RootUserNamespace: creds.UserNamespace,
- NetworkStack: networkStack,
+ RootNetworkNamespace: netns,
ApplicationCores: uint(args.NumCPU),
Vdso: vdso,
RootUTSNamespace: kernel.NewUTSNamespace(args.Spec.Hostname, args.Spec.Hostname, creds.UserNamespace),
@@ -300,7 +313,9 @@ func New(args Args) (*Loader, error) {
}
// Create a watchdog.
- dog := watchdog.New(k, watchdog.DefaultTimeout, args.Conf.WatchdogAction)
+ dogOpts := watchdog.DefaultOpts
+ dogOpts.TaskTimeoutAction = args.Conf.WatchdogAction
+ dog := watchdog.New(k, dogOpts)
procArgs, err := newProcess(args.ID, args.Spec, creds, k, k.RootPIDNamespace())
if err != nil {
@@ -316,6 +331,35 @@ func New(args Args) (*Loader, error) {
return nil, fmt.Errorf("creating pod mount hints: %v", err)
}
+ if kernel.VFS2Enabled {
+ // Set up host mount that will be used for imported fds.
+ hostFilesystem := vfs2host.NewFilesystem(k.VFS())
+ defer hostFilesystem.DecRef()
+ hostMount, err := k.VFS().NewDisconnectedMount(hostFilesystem, nil, &vfs.MountOptions{})
+ if err != nil {
+ return nil, fmt.Errorf("failed to create hostfs mount: %v", err)
+ }
+ k.SetHostMount(hostMount)
+ }
+
+ // Make host FDs stable between invocations. Host FDs must map to the exact
+ // same number when the sandbox is restored. Otherwise the wrong FD will be
+ // used.
+ var stdioFDs []int
+ newfd := startingStdioFD
+ for _, fd := range args.StdioFDs {
+ err := syscall.Dup3(fd, newfd, syscall.O_CLOEXEC)
+ if err != nil {
+ return nil, fmt.Errorf("dup3 of stdioFDs failed: %v", err)
+ }
+ stdioFDs = append(stdioFDs, newfd)
+ err = syscall.Close(fd)
+ if err != nil {
+ return nil, fmt.Errorf("close original stdioFDs failed: %v", err)
+ }
+ newfd++
+ }
+
eid := execID{cid: args.ID}
l := &Loader{
k: k,
@@ -324,7 +368,7 @@ func New(args Args) (*Loader, error) {
watchdog: dog,
spec: args.Spec,
goferFDs: args.GoferFDs,
- stdioFDs: args.StdioFDs,
+ stdioFDs: stdioFDs,
rootProcArgs: procArgs,
sandboxID: args.ID,
processes: map[execID]*execProcess{eid: {}},
@@ -337,29 +381,6 @@ func New(args Args) (*Loader, error) {
return nil, fmt.Errorf("ignore child stop signals failed: %v", err)
}
- // Handle signals by forwarding them to the root container process
- // (except for panic signal, which should cause a panic).
- l.startSignalForwarding = sighandling.PrepareHandler(func(sig linux.Signal) {
- // Panic signal should cause a panic.
- if args.Conf.PanicSignal != -1 && sig == linux.Signal(args.Conf.PanicSignal) {
- panic("Signal-induced panic")
- }
-
- // Otherwise forward to root container.
- deliveryMode := DeliverToProcess
- if args.Console {
- // Since we are running with a console, we should
- // forward the signal to the foreground process group
- // so that job control signals like ^C can be handled
- // properly.
- deliveryMode = DeliverToForegroundProcessGroup
- }
- log.Infof("Received external signal %d, mode: %v", sig, deliveryMode)
- if err := l.signal(args.ID, 0, int32(sig), deliveryMode); err != nil {
- log.Warningf("error sending signal %v to container %q: %v", sig, args.ID, err)
- }
- })
-
// Create the control server using the provided FD.
//
// This must be done *after* we have initialized the kernel since the
@@ -387,11 +408,16 @@ func newProcess(id string, spec *specs.Spec, creds *auth.Credentials, k *kernel.
return kernel.CreateProcessArgs{}, fmt.Errorf("creating limits: %v", err)
}
+ wd := spec.Process.Cwd
+ if wd == "" {
+ wd = "/"
+ }
+
// Create the process arguments.
procArgs := kernel.CreateProcessArgs{
Argv: spec.Process.Args,
Envv: spec.Process.Env,
- WorkingDirectory: spec.Process.Cwd, // Defaults to '/' if empty.
+ WorkingDirectory: wd,
Credentials: creds,
Umask: 0022,
Limits: ls,
@@ -485,7 +511,7 @@ func (l *Loader) run() error {
// Delay host network configuration to this point because network namespace
// is configured after the loader is created and before Run() is called.
log.Debugf("Configuring host network")
- stack := l.k.NetworkStack().(*hostinet.Stack)
+ stack := l.k.RootNetworkNamespace().Stack().(*hostinet.Stack)
if err := stack.Configure(); err != nil {
return err
}
@@ -504,7 +530,7 @@ func (l *Loader) run() error {
// l.restore is set by the container manager when a restore call is made.
if !l.restore {
if l.conf.ProfileEnable {
- initializePProf()
+ pprof.Initialize()
}
// Finally done with all configuration. Setup filters before user code
@@ -536,7 +562,15 @@ func (l *Loader) run() error {
}
// Add the HOME enviroment variable if it is not already set.
- envv, err := maybeAddExecUserHome(ctx, l.rootProcArgs.MountNamespace, l.rootProcArgs.Credentials.RealKUID, l.rootProcArgs.Envv)
+ var envv []string
+ if kernel.VFS2Enabled {
+ envv, err = user.MaybeAddExecUserHomeVFS2(ctx, l.rootProcArgs.MountNamespaceVFS2,
+ l.rootProcArgs.Credentials.RealKUID, l.rootProcArgs.Envv)
+
+ } else {
+ envv, err = user.MaybeAddExecUserHome(ctx, l.rootProcArgs.MountNamespace,
+ l.rootProcArgs.Credentials.RealKUID, l.rootProcArgs.Envv)
+ }
if err != nil {
return err
}
@@ -567,8 +601,40 @@ func (l *Loader) run() error {
ep.tty.InitForegroundProcessGroup(ep.tg.ProcessGroup())
}
- // Start signal forwarding only after an init process is created.
- l.stopSignalForwarding = l.startSignalForwarding()
+ // Handle signals by forwarding them to the root container process
+ // (except for panic signal, which should cause a panic).
+ l.stopSignalForwarding = sighandling.StartSignalForwarding(func(sig linux.Signal) {
+ // Panic signal should cause a panic.
+ if l.conf.PanicSignal != -1 && sig == linux.Signal(l.conf.PanicSignal) {
+ panic("Signal-induced panic")
+ }
+
+ // Otherwise forward to root container.
+ deliveryMode := DeliverToProcess
+ if l.console {
+ // Since we are running with a console, we should forward the signal to
+ // the foreground process group so that job control signals like ^C can
+ // be handled properly.
+ deliveryMode = DeliverToForegroundProcessGroup
+ }
+ log.Infof("Received external signal %d, mode: %v", sig, deliveryMode)
+ if err := l.signal(l.sandboxID, 0, int32(sig), deliveryMode); err != nil {
+ log.Warningf("error sending signal %v to container %q: %v", sig, l.sandboxID, err)
+ }
+ })
+
+ // l.stdioFDs are derived from dup() in boot.New() and they are now dup()ed again
+ // either in createFDTable() during initial start or in descriptor.initAfterLoad()
+ // during restore, we can release l.stdioFDs now. VFS2 takes ownership of the
+ // passed FDs, so only close for VFS1.
+ if !kernel.VFS2Enabled {
+ for _, fd := range l.stdioFDs {
+ err := syscall.Close(fd)
+ if err != nil {
+ return fmt.Errorf("close dup()ed stdioFDs: %v", err)
+ }
+ }
+ }
log.Infof("Process should have started...")
l.watchdog.Start()
@@ -795,20 +861,23 @@ func (l *Loader) executeAsync(args *control.ExecArgs) (kernel.ThreadID, error) {
return 0, fmt.Errorf("container %q not started", args.ContainerID)
}
+ // TODO(gvisor.dev/issue/1623): Add VFS2 support
+
// Get the container MountNamespace from the Task.
tg.Leader().WithMuLocked(func(t *kernel.Task) {
- // task.MountNamespace() does not take a ref, so we must do so
- // ourselves.
+ // task.MountNamespace() does not take a ref, so we must do so ourselves.
args.MountNamespace = t.MountNamespace()
args.MountNamespace.IncRef()
})
- defer args.MountNamespace.DecRef()
+ if args.MountNamespace != nil {
+ defer args.MountNamespace.DecRef()
+ }
- // Add the HOME enviroment varible if it is not already set.
+ // Add the HOME environment variable if it is not already set.
root := args.MountNamespace.Root()
defer root.DecRef()
ctx := fs.WithRoot(l.k.SupervisorContext(), root)
- envv, err := maybeAddExecUserHome(ctx, args.MountNamespace, args.KUID, args.Envv)
+ envv, err := user.MaybeAddExecUserHome(ctx, args.MountNamespace, args.KUID, args.Envv)
if err != nil {
return 0, err
}
@@ -905,47 +974,92 @@ func (l *Loader) WaitExit() kernel.ExitStatus {
return l.k.GlobalInit().ExitStatus()
}
-func newEmptyNetworkStack(conf *Config, clock tcpip.Clock) (inet.Stack, error) {
+func newRootNetworkNamespace(conf *Config, clock tcpip.Clock, uniqueID stack.UniqueID) (*inet.Namespace, error) {
+ // Create an empty network stack because the network namespace may be empty at
+ // this point. Netns is configured before Run() is called. Netstack is
+ // configured using a control uRPC message. Host network is configured inside
+ // Run().
switch conf.Network {
case NetworkHost:
- return hostinet.NewStack(), nil
+ // No network namespacing support for hostinet yet, hence creator is nil.
+ return inet.NewRootNamespace(hostinet.NewStack(), nil), nil
case NetworkNone, NetworkSandbox:
- // NetworkNone sets up loopback using netstack.
- netProtos := []stack.NetworkProtocol{ipv4.NewProtocol(), ipv6.NewProtocol(), arp.NewProtocol()}
- transProtos := []stack.TransportProtocol{tcp.NewProtocol(), udp.NewProtocol(), icmp.NewProtocol4()}
- s := netstack.Stack{stack.New(stack.Options{
- NetworkProtocols: netProtos,
- TransportProtocols: transProtos,
- Clock: clock,
- Stats: netstack.Metrics,
- HandleLocal: true,
- // Enable raw sockets for users with sufficient
- // privileges.
- RawFactory: raw.EndpointFactory{},
- })}
-
- // Enable SACK Recovery.
- if err := s.Stack.SetTransportProtocolOption(tcp.ProtocolNumber, tcp.SACKEnabled(true)); err != nil {
- return nil, fmt.Errorf("failed to enable SACK: %v", err)
+ s, err := newEmptySandboxNetworkStack(clock, uniqueID)
+ if err != nil {
+ return nil, err
+ }
+ creator := &sandboxNetstackCreator{
+ clock: clock,
+ uniqueID: uniqueID,
}
+ return inet.NewRootNamespace(s, creator), nil
- // Set default TTLs as required by socket/netstack.
- s.Stack.SetNetworkProtocolOption(ipv4.ProtocolNumber, tcpip.DefaultTTLOption(netstack.DefaultTTL))
- s.Stack.SetNetworkProtocolOption(ipv6.ProtocolNumber, tcpip.DefaultTTLOption(netstack.DefaultTTL))
+ default:
+ panic(fmt.Sprintf("invalid network configuration: %v", conf.Network))
+ }
- // Enable Receive Buffer Auto-Tuning.
- if err := s.Stack.SetTransportProtocolOption(tcp.ProtocolNumber, tcpip.ModerateReceiveBufferOption(true)); err != nil {
- return nil, fmt.Errorf("SetTransportProtocolOption failed: %v", err)
- }
+}
- s.FillDefaultIPTables()
+func newEmptySandboxNetworkStack(clock tcpip.Clock, uniqueID stack.UniqueID) (inet.Stack, error) {
+ netProtos := []stack.NetworkProtocol{ipv4.NewProtocol(), ipv6.NewProtocol(), arp.NewProtocol()}
+ transProtos := []stack.TransportProtocol{tcp.NewProtocol(), udp.NewProtocol(), icmp.NewProtocol4()}
+ s := netstack.Stack{stack.New(stack.Options{
+ NetworkProtocols: netProtos,
+ TransportProtocols: transProtos,
+ Clock: clock,
+ Stats: netstack.Metrics,
+ HandleLocal: true,
+ // Enable raw sockets for users with sufficient
+ // privileges.
+ RawFactory: raw.EndpointFactory{},
+ UniqueID: uniqueID,
+ })}
- return &s, nil
+ // Enable SACK Recovery.
+ if err := s.Stack.SetTransportProtocolOption(tcp.ProtocolNumber, tcp.SACKEnabled(true)); err != nil {
+ return nil, fmt.Errorf("failed to enable SACK: %v", err)
+ }
- default:
- panic(fmt.Sprintf("invalid network configuration: %v", conf.Network))
+ // Set default TTLs as required by socket/netstack.
+ s.Stack.SetNetworkProtocolOption(ipv4.ProtocolNumber, tcpip.DefaultTTLOption(netstack.DefaultTTL))
+ s.Stack.SetNetworkProtocolOption(ipv6.ProtocolNumber, tcpip.DefaultTTLOption(netstack.DefaultTTL))
+
+ // Enable Receive Buffer Auto-Tuning.
+ if err := s.Stack.SetTransportProtocolOption(tcp.ProtocolNumber, tcpip.ModerateReceiveBufferOption(true)); err != nil {
+ return nil, fmt.Errorf("SetTransportProtocolOption failed: %v", err)
}
+
+ s.FillDefaultIPTables()
+
+ return &s, nil
+}
+
+// sandboxNetstackCreator implements kernel.NetworkStackCreator.
+//
+// +stateify savable
+type sandboxNetstackCreator struct {
+ clock tcpip.Clock
+ uniqueID stack.UniqueID
+}
+
+// CreateStack implements kernel.NetworkStackCreator.CreateStack.
+func (f *sandboxNetstackCreator) CreateStack() (inet.Stack, error) {
+ s, err := newEmptySandboxNetworkStack(f.clock, f.uniqueID)
+ if err != nil {
+ return nil, err
+ }
+
+ // Setup loopback.
+ n := &Network{Stack: s.(*netstack.Stack).Stack}
+ nicID := tcpip.NICID(f.uniqueID.UniqueID())
+ link := DefaultLoopbackLink
+ linkEP := loopback.New()
+ if err := n.createNICWithAddrs(nicID, link.Name, linkEP, link.Addresses); err != nil {
+ return nil, err
+ }
+
+ return s, nil
}
// signal sends a signal to one or more processes in a container. If PID is 0,
@@ -993,7 +1107,7 @@ func (l *Loader) signalProcess(cid string, tgid kernel.ThreadID, signo int32) er
execTG, _, err := l.threadGroupFromID(execID{cid: cid, pid: tgid})
if err == nil {
// Send signal directly to the identified process.
- return execTG.SendSignal(&arch.SignalInfo{Signo: signo})
+ return l.k.SendExternalSignalThreadGroup(execTG, &arch.SignalInfo{Signo: signo})
}
// The caller may be signaling a process not started directly via exec.
@@ -1010,7 +1124,7 @@ func (l *Loader) signalProcess(cid string, tgid kernel.ThreadID, signo int32) er
if tg.Leader().ContainerID() != cid {
return fmt.Errorf("process %d is part of a different container: %q", tgid, tg.Leader().ContainerID())
}
- return tg.SendSignal(&arch.SignalInfo{Signo: signo})
+ return l.k.SendExternalSignalThreadGroup(tg, &arch.SignalInfo{Signo: signo})
}
func (l *Loader) signalForegrondProcessGroup(cid string, tgid kernel.ThreadID, signo int32) error {
@@ -1028,7 +1142,7 @@ func (l *Loader) signalForegrondProcessGroup(cid string, tgid kernel.ThreadID, s
// No foreground process group has been set. Signal the
// original thread group.
log.Warningf("No foreground process group for container %q and PID %d. Sending signal directly to PID %d.", cid, tgid, tgid)
- return tg.SendSignal(&arch.SignalInfo{Signo: signo})
+ return l.k.SendExternalSignalThreadGroup(tg, &arch.SignalInfo{Signo: signo})
}
// Send the signal to all processes in the process group.
var lastErr error
@@ -1036,7 +1150,7 @@ func (l *Loader) signalForegrondProcessGroup(cid string, tgid kernel.ThreadID, s
if tg.ProcessGroup() != pg {
continue
}
- if err := tg.SendSignal(&arch.SignalInfo{Signo: signo}); err != nil {
+ if err := l.k.SendExternalSignalThreadGroup(tg, &arch.SignalInfo{Signo: signo}); err != nil {
lastErr = err
}
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-11 12:29:52 +0000