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Diffstat (limited to 'runsc/boot/loader.go')
-rw-r--r--runsc/boot/loader.go201
1 files changed, 120 insertions, 81 deletions
diff --git a/runsc/boot/loader.go b/runsc/boot/loader.go
index 9cd9c5909..2e652ddad 100644
--- a/runsc/boot/loader.go
+++ b/runsc/boot/loader.go
@@ -16,22 +16,25 @@
package boot
import (
+ "errors"
"fmt"
mrand "math/rand"
"os"
"runtime"
"sync/atomic"
- "syscall"
gtime "time"
specs "github.com/opencontainers/runtime-spec/specs-go"
"golang.org/x/sys/unix"
"gvisor.dev/gvisor/pkg/abi/linux"
+ "gvisor.dev/gvisor/pkg/bpf"
"gvisor.dev/gvisor/pkg/context"
"gvisor.dev/gvisor/pkg/cpuid"
+ "gvisor.dev/gvisor/pkg/fd"
"gvisor.dev/gvisor/pkg/log"
"gvisor.dev/gvisor/pkg/memutil"
"gvisor.dev/gvisor/pkg/rand"
+ "gvisor.dev/gvisor/pkg/refs"
"gvisor.dev/gvisor/pkg/sentry/arch"
"gvisor.dev/gvisor/pkg/sentry/control"
"gvisor.dev/gvisor/pkg/sentry/fdimport"
@@ -66,7 +69,9 @@ import (
"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/config"
"gvisor.dev/gvisor/runsc/specutils"
+ "gvisor.dev/gvisor/runsc/specutils/seccomp"
// Include supported socket providers.
"gvisor.dev/gvisor/pkg/sentry/socket/hostinet"
@@ -78,7 +83,7 @@ import (
)
type containerInfo struct {
- conf *Config
+ conf *config.Config
// spec is the base configuration for the root container.
spec *specs.Spec
@@ -87,10 +92,10 @@ type containerInfo struct {
procArgs kernel.CreateProcessArgs
// stdioFDs contains stdin, stdout, and stderr.
- stdioFDs []int
+ stdioFDs []*fd.FD
// goferFDs are the FDs that attach the sandbox to the gofers.
- goferFDs []int
+ goferFDs []*fd.FD
}
// Loader keeps state needed to start the kernel and run the container..
@@ -164,7 +169,7 @@ type Args struct {
// Spec is the sandbox specification.
Spec *specs.Spec
// Conf is the system configuration.
- Conf *Config
+ Conf *config.Config
// ControllerFD is the FD to the URPC controller. The Loader takes ownership
// of this FD and may close it at any time.
ControllerFD int
@@ -187,7 +192,7 @@ type Args struct {
}
// make sure stdioFDs are always the same on initial start and on restore
-const startingStdioFD = 64
+const startingStdioFD = 256
// New initializes a new kernel loader configured by spec.
// New also handles setting up a kernel for restoring a container.
@@ -346,7 +351,7 @@ func New(args Args) (*Loader, error) {
if err != nil {
return nil, fmt.Errorf("failed to create hostfs filesystem: %v", err)
}
- defer hostFilesystem.DecRef()
+ defer hostFilesystem.DecRef(k.SupervisorContext())
hostMount, err := k.VFS().NewDisconnectedMount(hostFilesystem, nil, &vfs.MountOptions{})
if err != nil {
return nil, fmt.Errorf("failed to create hostfs mount: %v", err)
@@ -354,23 +359,36 @@ func New(args Args) (*Loader, error) {
k.SetHostMount(hostMount)
}
+ info := containerInfo{
+ conf: args.Conf,
+ spec: args.Spec,
+ procArgs: procArgs,
+ }
+
// 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)
+ for _, stdioFD := range args.StdioFDs {
+ // Check that newfd is unused to avoid clobbering over it.
+ if _, err := unix.FcntlInt(uintptr(newfd), unix.F_GETFD, 0); !errors.Is(err, unix.EBADF) {
+ if err != nil {
+ return nil, fmt.Errorf("error checking for FD (%d) conflict: %w", newfd, err)
+ }
+ return nil, fmt.Errorf("unable to remap stdios, FD %d is already in use", newfd)
}
- stdioFDs = append(stdioFDs, newfd)
- err = syscall.Close(fd)
+
+ err := unix.Dup3(stdioFD, newfd, unix.O_CLOEXEC)
if err != nil {
- return nil, fmt.Errorf("close original stdioFDs failed: %v", err)
+ return nil, fmt.Errorf("dup3 of stdios failed: %w", err)
}
+ info.stdioFDs = append(info.stdioFDs, fd.New(newfd))
+ _ = unix.Close(stdioFD)
newfd++
}
+ for _, goferFD := range args.GoferFDs {
+ info.goferFDs = append(info.goferFDs, fd.New(goferFD))
+ }
eid := execID{cid: args.ID}
l := &Loader{
@@ -379,13 +397,7 @@ func New(args Args) (*Loader, error) {
sandboxID: args.ID,
processes: map[execID]*execProcess{eid: {}},
mountHints: mountHints,
- root: containerInfo{
- conf: args.Conf,
- stdioFDs: stdioFDs,
- goferFDs: args.GoferFDs,
- spec: args.Spec,
- procArgs: procArgs,
- },
+ root: info,
}
// We don't care about child signals; some platforms can generate a
@@ -458,9 +470,19 @@ func (l *Loader) Destroy() {
l.stopSignalForwarding()
}
l.watchdog.Stop()
+
+ // In the success case, stdioFDs and goferFDs will only contain
+ // released/closed FDs that ownership has been passed over to host FDs and
+ // gofer sessions. Close them here in case on failure.
+ for _, fd := range l.root.stdioFDs {
+ _ = fd.Close()
+ }
+ for _, fd := range l.root.goferFDs {
+ _ = fd.Close()
+ }
}
-func createPlatform(conf *Config, deviceFile *os.File) (platform.Platform, error) {
+func createPlatform(conf *config.Config, deviceFile *os.File) (platform.Platform, error) {
p, err := platform.Lookup(conf.Platform)
if err != nil {
panic(fmt.Sprintf("invalid platform %v: %v", conf.Platform, err))
@@ -487,13 +509,14 @@ func createMemoryFile() (*pgalloc.MemoryFile, error) {
return mf, nil
}
+// installSeccompFilters installs sandbox seccomp filters with the host.
func (l *Loader) installSeccompFilters() error {
if l.root.conf.DisableSeccomp {
filter.Report("syscall filter is DISABLED. Running in less secure mode.")
} else {
opts := filter.Options{
Platform: l.k.Platform,
- HostNetwork: l.root.conf.Network == NetworkHost,
+ HostNetwork: l.root.conf.Network == config.NetworkHost,
ProfileEnable: l.root.conf.ProfileEnable,
ControllerFD: l.ctrl.srv.FD(),
}
@@ -520,7 +543,7 @@ func (l *Loader) Run() error {
}
func (l *Loader) run() error {
- if l.root.conf.Network == NetworkHost {
+ if l.root.conf.Network == config.NetworkHost {
// 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")
@@ -557,6 +580,7 @@ func (l *Loader) run() error {
if _, err := l.createContainerProcess(true, l.sandboxID, &l.root, ep); err != nil {
return err
}
+
}
ep.tg = l.k.GlobalInit()
@@ -586,19 +610,6 @@ func (l *Loader) run() error {
}
})
- // 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.root.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()
return l.k.Start()
@@ -618,9 +629,9 @@ func (l *Loader) createContainer(cid string) error {
}
// startContainer starts a child container. It returns the thread group ID of
-// the newly created process. Caller owns 'files' and may close them after
-// this method returns.
-func (l *Loader) startContainer(spec *specs.Spec, conf *Config, cid string, files []*os.File) error {
+// the newly created process. Used FDs are either closed or released. It's safe
+// for the caller to close any remaining files upon return.
+func (l *Loader) startContainer(spec *specs.Spec, conf *config.Config, cid string, files []*fd.FD) error {
// Create capabilities.
caps, err := specutils.Capabilities(conf.EnableRaw, spec.Process.Capabilities)
if err != nil {
@@ -671,28 +682,15 @@ func (l *Loader) startContainer(spec *specs.Spec, conf *Config, cid string, file
}
info := &containerInfo{
- conf: conf,
- spec: spec,
+ conf: conf,
+ spec: spec,
+ stdioFDs: files[:3],
+ goferFDs: files[3:],
}
info.procArgs, err = createProcessArgs(cid, spec, creds, l.k, pidns)
if err != nil {
return fmt.Errorf("creating new process: %v", err)
}
-
- // setupContainerFS() dups stdioFDs, so we don't need to dup them here.
- for _, f := range files[:3] {
- info.stdioFDs = append(info.stdioFDs, int(f.Fd()))
- }
-
- // Can't take ownership away from os.File. dup them to get a new FDs.
- for _, f := range files[3:] {
- fd, err := syscall.Dup(int(f.Fd()))
- if err != nil {
- return fmt.Errorf("failed to dup file: %v", err)
- }
- info.goferFDs = append(info.goferFDs, fd)
- }
-
tg, err := l.createContainerProcess(false, cid, info, ep)
if err != nil {
return err
@@ -755,7 +753,7 @@ func (l *Loader) createContainerProcess(root bool, cid string, info *containerIn
return nil, fmt.Errorf("creating process: %v", err)
}
// CreateProcess takes a reference on FDTable if successful.
- info.procArgs.FDTable.DecRef()
+ info.procArgs.FDTable.DecRef(ctx)
// Set the foreground process group on the TTY to the global init process
// group, since that is what we are about to start running.
@@ -770,19 +768,44 @@ func (l *Loader) createContainerProcess(root bool, cid string, info *containerIn
}
}
+ // Install seccomp filters with the new task if there are any.
+ if info.conf.OCISeccomp {
+ if info.spec.Linux != nil && info.spec.Linux.Seccomp != nil {
+ program, err := seccomp.BuildProgram(info.spec.Linux.Seccomp)
+ if err != nil {
+ return nil, fmt.Errorf("building seccomp program: %v", err)
+ }
+
+ if log.IsLogging(log.Debug) {
+ out, _ := bpf.DecodeProgram(program)
+ log.Debugf("Installing OCI seccomp filters\nProgram:\n%s", out)
+ }
+
+ task := tg.Leader()
+ // NOTE: It seems Flags are ignored by runc so we ignore them too.
+ if err := task.AppendSyscallFilter(program, true); err != nil {
+ return nil, fmt.Errorf("appending seccomp filters: %v", err)
+ }
+ }
+ } else {
+ if info.spec.Linux != nil && info.spec.Linux.Seccomp != nil {
+ log.Warningf("Seccomp spec is being ignored")
+ }
+ }
+
return tg, nil
}
// startGoferMonitor runs a goroutine to monitor gofer's health. It polls on
// the gofer FDs looking for disconnects, and destroys the container if a
// disconnect occurs in any of the gofer FDs.
-func (l *Loader) startGoferMonitor(cid string, goferFDs []int) {
+func (l *Loader) startGoferMonitor(cid string, goferFDs []*fd.FD) {
go func() {
log.Debugf("Monitoring gofer health for container %q", cid)
var events []unix.PollFd
- for _, fd := range goferFDs {
+ for _, goferFD := range goferFDs {
events = append(events, unix.PollFd{
- Fd: int32(fd),
+ Fd: int32(goferFD.FD()),
Events: unix.POLLHUP | unix.POLLRDHUP,
})
}
@@ -890,22 +913,20 @@ func (l *Loader) executeAsync(args *control.ExecArgs) (kernel.ThreadID, error) {
// Add the HOME environment variable if it is not already set.
if kernel.VFS2Enabled {
- defer args.MountNamespaceVFS2.DecRef()
-
root := args.MountNamespaceVFS2.Root()
- defer root.DecRef()
ctx := vfs.WithRoot(l.k.SupervisorContext(), root)
+ defer args.MountNamespaceVFS2.DecRef(ctx)
+ defer root.DecRef(ctx)
envv, err := user.MaybeAddExecUserHomeVFS2(ctx, args.MountNamespaceVFS2, args.KUID, args.Envv)
if err != nil {
return 0, err
}
args.Envv = envv
} else {
- defer args.MountNamespace.DecRef()
-
root := args.MountNamespace.Root()
- defer root.DecRef()
ctx := fs.WithRoot(l.k.SupervisorContext(), root)
+ defer args.MountNamespace.DecRef(ctx)
+ defer root.DecRef(ctx)
envv, err := user.MaybeAddExecUserHome(ctx, args.MountNamespace, args.KUID, args.Envv)
if err != nil {
return 0, err
@@ -1002,20 +1023,25 @@ func (l *Loader) WaitExit() kernel.ExitStatus {
// Wait for container.
l.k.WaitExited()
+ // Cleanup
+ l.ctrl.stop()
+
+ refs.OnExit()
+
return l.k.GlobalInit().ExitStatus()
}
-func newRootNetworkNamespace(conf *Config, clock tcpip.Clock, uniqueID stack.UniqueID) (*inet.Namespace, error) {
+func newRootNetworkNamespace(conf *config.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:
+ case config.NetworkHost:
// No network namespacing support for hostinet yet, hence creator is nil.
return inet.NewRootNamespace(hostinet.NewStack(), nil), nil
- case NetworkNone, NetworkSandbox:
+ case config.NetworkNone, config.NetworkSandbox:
s, err := newEmptySandboxNetworkStack(clock, uniqueID)
if err != nil {
return nil, err
@@ -1033,8 +1059,8 @@ func newRootNetworkNamespace(conf *Config, clock tcpip.Clock, uniqueID stack.Uni
}
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()}
+ netProtos := []stack.NetworkProtocolFactory{ipv4.NewProtocol, ipv6.NewProtocol, arp.NewProtocol}
+ transProtos := []stack.TransportProtocolFactory{tcp.NewProtocol, udp.NewProtocol, icmp.NewProtocol4}
s := netstack.Stack{stack.New(stack.Options{
NetworkProtocols: netProtos,
TransportProtocols: transProtos,
@@ -1048,17 +1074,30 @@ func newEmptySandboxNetworkStack(clock tcpip.Clock, uniqueID stack.UniqueID) (in
})}
// Enable SACK Recovery.
- if err := s.Stack.SetTransportProtocolOption(tcp.ProtocolNumber, tcp.SACKEnabled(true)); err != nil {
- return nil, fmt.Errorf("failed to enable SACK: %s", err)
+ {
+ opt := tcpip.TCPSACKEnabled(true)
+ if err := s.Stack.SetTransportProtocolOption(tcp.ProtocolNumber, &opt); err != nil {
+ return nil, fmt.Errorf("SetTransportProtocolOption(%d, &%T(%t)): %s", tcp.ProtocolNumber, opt, opt, err)
+ }
}
// 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))
+ {
+ opt := tcpip.DefaultTTLOption(netstack.DefaultTTL)
+ if err := s.Stack.SetNetworkProtocolOption(ipv4.ProtocolNumber, &opt); err != nil {
+ return nil, fmt.Errorf("SetNetworkProtocolOption(%d, &%T(%d)): %s", ipv4.ProtocolNumber, opt, opt, err)
+ }
+ if err := s.Stack.SetNetworkProtocolOption(ipv6.ProtocolNumber, &opt); err != nil {
+ return nil, fmt.Errorf("SetNetworkProtocolOption(%d, &%T(%d)): %s", ipv6.ProtocolNumber, opt, opt, err)
+ }
+ }
// Enable Receive Buffer Auto-Tuning.
- if err := s.Stack.SetTransportProtocolOption(tcp.ProtocolNumber, tcpip.ModerateReceiveBufferOption(true)); err != nil {
- return nil, fmt.Errorf("SetTransportProtocolOption failed: %s", err)
+ {
+ opt := tcpip.TCPModerateReceiveBufferOption(true)
+ if err := s.Stack.SetTransportProtocolOption(tcp.ProtocolNumber, &opt); err != nil {
+ return nil, fmt.Errorf("SetTransportProtocolOption(%d, &%T(%t)): %s", tcp.ProtocolNumber, opt, opt, err)
+ }
}
return &s, nil
@@ -1254,7 +1293,7 @@ func (l *Loader) ttyFromIDLocked(key execID) (*host.TTYFileOperations, *hostvfs2
return ep.tty, ep.ttyVFS2, nil
}
-func createFDTable(ctx context.Context, console bool, stdioFDs []int) (*kernel.FDTable, *host.TTYFileOperations, *hostvfs2.TTYFileDescription, error) {
+func createFDTable(ctx context.Context, console bool, stdioFDs []*fd.FD) (*kernel.FDTable, *host.TTYFileOperations, *hostvfs2.TTYFileDescription, error) {
if len(stdioFDs) != 3 {
return nil, nil, nil, fmt.Errorf("stdioFDs should contain exactly 3 FDs (stdin, stdout, and stderr), but %d FDs received", len(stdioFDs))
}
@@ -1263,7 +1302,7 @@ func createFDTable(ctx context.Context, console bool, stdioFDs []int) (*kernel.F
fdTable := k.NewFDTable()
ttyFile, ttyFileVFS2, err := fdimport.Import(ctx, fdTable, console, stdioFDs)
if err != nil {
- fdTable.DecRef()
+ fdTable.DecRef(ctx)
return nil, nil, nil, err
}
return fdTable, ttyFile, ttyFileVFS2, nil
generated by cgit v1.2.3 (git 2.39.1) at 2025-04-09 18:33:28 +0000