diff options
| -rw-r--r-- | runsc/boot/config.go | 5 | ||||
| -rw-r--r-- | runsc/cmd/gofer.go | 18 | ||||
| -rw-r--r-- | runsc/container/container.go | 5 | ||||
| -rw-r--r-- | runsc/fsgofer/fsgofer.go | 10 | ||||
| -rw-r--r-- | runsc/main.go | 68 |
5 files changed, 52 insertions, 54 deletions
diff --git a/runsc/boot/config.go b/runsc/boot/config.go index f1adaba01..b76b0e574 100644 --- a/runsc/boot/config.go +++ b/runsc/boot/config.go @@ -138,8 +138,8 @@ type Config struct { // Overlay is whether to wrap the root filesystem in an overlay. Overlay bool - // FSGoferHostUDSAllowed enables the gofer to mount a host UDS. - FSGoferHostUDSAllowed bool + // FSGoferHostUDS enables the gofer to mount a host UDS. + FSGoferHostUDS bool // Network indicates what type of network to use. Network NetworkType @@ -217,6 +217,7 @@ func (c *Config) ToFlags() []string { "--debug-log-format=" + c.DebugLogFormat, "--file-access=" + c.FileAccess.String(), "--overlay=" + strconv.FormatBool(c.Overlay), + "--fsgofer-host-uds=" + strconv.FormatBool(c.FSGoferHostUDS), "--network=" + c.Network.String(), "--log-packets=" + strconv.FormatBool(c.LogPackets), "--platform=" + c.Platform, diff --git a/runsc/cmd/gofer.go b/runsc/cmd/gofer.go index fa4f0034d..fbd579fb8 100644 --- a/runsc/cmd/gofer.go +++ b/runsc/cmd/gofer.go @@ -56,11 +56,10 @@ var goferCaps = &specs.LinuxCapabilities{ // Gofer implements subcommands.Command for the "gofer" command, which starts a // filesystem gofer. This command should not be called directly. type Gofer struct { - bundleDir string - ioFDs intFlags - applyCaps bool - hostUDSAllowed bool - setUpRoot bool + bundleDir string + ioFDs intFlags + applyCaps bool + setUpRoot bool panicOnWrite bool specFD int @@ -87,7 +86,6 @@ func (g *Gofer) SetFlags(f *flag.FlagSet) { f.StringVar(&g.bundleDir, "bundle", "", "path to the root of the bundle directory, defaults to the current directory") f.Var(&g.ioFDs, "io-fds", "list of FDs to connect 9P servers. They must follow this order: root first, then mounts as defined in the spec") f.BoolVar(&g.applyCaps, "apply-caps", true, "if true, apply capabilities to restrict what the Gofer process can do") - f.BoolVar(&g.hostUDSAllowed, "host-uds-allowed", false, "if true, allow the Gofer to mount a host UDS") f.BoolVar(&g.panicOnWrite, "panic-on-write", false, "if true, panics on attempts to write to RO mounts. RW mounts are unnaffected") f.BoolVar(&g.setUpRoot, "setup-root", true, "if true, set up an empty root for the process") f.IntVar(&g.specFD, "spec-fd", -1, "required fd with the container spec") @@ -182,9 +180,9 @@ func (g *Gofer) Execute(_ context.Context, f *flag.FlagSet, args ...interface{}) for _, m := range spec.Mounts { if specutils.Is9PMount(m) { cfg := fsgofer.Config{ - ROMount: isReadonlyMount(m.Options), - PanicOnWrite: g.panicOnWrite, - HostUDSAllowed: g.hostUDSAllowed, + ROMount: isReadonlyMount(m.Options), + PanicOnWrite: g.panicOnWrite, + HostUDS: conf.FSGoferHostUDS, } ap, err := fsgofer.NewAttachPoint(m.Destination, cfg) if err != nil { @@ -203,7 +201,7 @@ func (g *Gofer) Execute(_ context.Context, f *flag.FlagSet, args ...interface{}) Fatalf("too many FDs passed for mounts. mounts: %d, FDs: %d", mountIdx, len(g.ioFDs)) } - if g.hostUDSAllowed { + if conf.FSGoferHostUDS { filter.InstallUDSFilters() } diff --git a/runsc/container/container.go b/runsc/container/container.go index ceadb38aa..bbb364214 100644 --- a/runsc/container/container.go +++ b/runsc/container/container.go @@ -941,11 +941,6 @@ func (c *Container) createGoferProcess(spec *specs.Spec, conf *boot.Config, bund args = append(args, "--panic-on-write=true") } - // Add support for mounting host UDS in the gofer - if conf.FSGoferHostUDSAllowed { - args = append(args, "--host-uds-allowed=true") - } - // Open the spec file to donate to the sandbox. specFile, err := specutils.OpenSpec(bundleDir) if err != nil { diff --git a/runsc/fsgofer/fsgofer.go b/runsc/fsgofer/fsgofer.go index 357d712c6..507d52b50 100644 --- a/runsc/fsgofer/fsgofer.go +++ b/runsc/fsgofer/fsgofer.go @@ -87,8 +87,8 @@ type Config struct { // PanicOnWrite panics on attempts to write to RO mounts. PanicOnWrite bool - // HostUDSAllowed signals whether the gofer can mount a host's UDS. - HostUDSAllowed bool + // HostUDS signals whether the gofer can mount a host's UDS. + HostUDS bool } type attachPoint struct { @@ -143,7 +143,7 @@ func (a *attachPoint) Attach() (p9.File, error) { switch fmtStat := stat.Mode & syscall.S_IFMT; fmtStat { case syscall.S_IFSOCK: // Check to see if the CLI option has been set to allow the UDS mount. - if !a.conf.HostUDSAllowed { + if !a.conf.HostUDS { return nil, errors.New("host UDS support is disabled") } @@ -1059,6 +1059,10 @@ func (l *localFile) Flush() error { // Connect implements p9.File. func (l *localFile) Connect(p9.ConnectFlags) (*fd.FD, error) { + // Check to see if the CLI option has been set to allow the UDS mount. + if !l.attachPoint.conf.HostUDS { + return nil, errors.New("host UDS support is disabled") + } return fd.DialUnix(l.hostPath) } diff --git a/runsc/main.go b/runsc/main.go index 5eba949f6..b788b1f76 100644 --- a/runsc/main.go +++ b/runsc/main.go @@ -63,18 +63,18 @@ var ( straceLogSize = flag.Uint("strace-log-size", 1024, "default size (in bytes) to log data argument blobs") // Flags that control sandbox runtime behavior. - platformName = flag.String("platform", "ptrace", "specifies which platform to use: ptrace (default), kvm") - network = flag.String("network", "sandbox", "specifies which network to use: sandbox (default), host, none. Using network inside the sandbox is more secure because it's isolated from the host network.") - gso = flag.Bool("gso", true, "enable generic segmenation offload") - fileAccess = flag.String("file-access", "exclusive", "specifies which filesystem to use for the root mount: exclusive (default), shared. Volume mounts are always shared.") - fsGoferHostUDSAllowed = flag.Bool("fsgofer-host-uds-allowed", false, "Allow the gofer to mount Unix Domain Sockets.") - overlay = flag.Bool("overlay", false, "wrap filesystem mounts with writable overlay. All modifications are stored in memory inside the sandbox.") - watchdogAction = flag.String("watchdog-action", "log", "sets what action the watchdog takes when triggered: log (default), panic.") - panicSignal = flag.Int("panic-signal", -1, "register signal handling that panics. Usually set to SIGUSR2(12) to troubleshoot hangs. -1 disables it.") - profile = flag.Bool("profile", false, "prepares the sandbox to use Golang profiler. Note that enabling profiler loosens the seccomp protection added to the sandbox (DO NOT USE IN PRODUCTION).") - netRaw = flag.Bool("net-raw", false, "enable raw sockets. When false, raw sockets are disabled by removing CAP_NET_RAW from containers (`runsc exec` will still be able to utilize raw sockets). Raw sockets allow malicious containers to craft packets and potentially attack the network.") - numNetworkChannels = flag.Int("num-network-channels", 1, "number of underlying channels(FDs) to use for network link endpoints.") - rootless = flag.Bool("rootless", false, "it allows the sandbox to be started with a user that is not root. Sandbox and Gofer processes may run with same privileges as current user.") + platformName = flag.String("platform", "ptrace", "specifies which platform to use: ptrace (default), kvm") + network = flag.String("network", "sandbox", "specifies which network to use: sandbox (default), host, none. Using network inside the sandbox is more secure because it's isolated from the host network.") + gso = flag.Bool("gso", true, "enable generic segmenation offload") + fileAccess = flag.String("file-access", "exclusive", "specifies which filesystem to use for the root mount: exclusive (default), shared. Volume mounts are always shared.") + fsGoferHostUDS = flag.Bool("fsgofer-host-uds", false, "Allow the gofer to mount Unix Domain Sockets.") + overlay = flag.Bool("overlay", false, "wrap filesystem mounts with writable overlay. All modifications are stored in memory inside the sandbox.") + watchdogAction = flag.String("watchdog-action", "log", "sets what action the watchdog takes when triggered: log (default), panic.") + panicSignal = flag.Int("panic-signal", -1, "register signal handling that panics. Usually set to SIGUSR2(12) to troubleshoot hangs. -1 disables it.") + profile = flag.Bool("profile", false, "prepares the sandbox to use Golang profiler. Note that enabling profiler loosens the seccomp protection added to the sandbox (DO NOT USE IN PRODUCTION).") + netRaw = flag.Bool("net-raw", false, "enable raw sockets. When false, raw sockets are disabled by removing CAP_NET_RAW from containers (`runsc exec` will still be able to utilize raw sockets). Raw sockets allow malicious containers to craft packets and potentially attack the network.") + numNetworkChannels = flag.Int("num-network-channels", 1, "number of underlying channels(FDs) to use for network link endpoints.") + rootless = flag.Bool("rootless", false, "it allows the sandbox to be started with a user that is not root. Sandbox and Gofer processes may run with same privileges as current user.") // Test flags, not to be used outside tests, ever. testOnlyAllowRunAsCurrentUserWithoutChroot = flag.Bool("TESTONLY-unsafe-nonroot", false, "TEST ONLY; do not ever use! This skips many security measures that isolate the host from the sandbox.") @@ -172,28 +172,28 @@ func main() { // Create a new Config from the flags. conf := &boot.Config{ - RootDir: *rootDir, - Debug: *debug, - LogFilename: *logFilename, - LogFormat: *logFormat, - DebugLog: *debugLog, - DebugLogFormat: *debugLogFormat, - FileAccess: fsAccess, - FSGoferHostUDSAllowed: *fsGoferHostUDSAllowed, - Overlay: *overlay, - Network: netType, - GSO: *gso, - LogPackets: *logPackets, - Platform: platformType, - Strace: *strace, - StraceLogSize: *straceLogSize, - WatchdogAction: wa, - PanicSignal: *panicSignal, - ProfileEnable: *profile, - EnableRaw: *netRaw, - NumNetworkChannels: *numNetworkChannels, - Rootless: *rootless, - AlsoLogToStderr: *alsoLogToStderr, + RootDir: *rootDir, + Debug: *debug, + LogFilename: *logFilename, + LogFormat: *logFormat, + DebugLog: *debugLog, + DebugLogFormat: *debugLogFormat, + FileAccess: fsAccess, + FSGoferHostUDS: *fsGoferHostUDS, + Overlay: *overlay, + Network: netType, + GSO: *gso, + LogPackets: *logPackets, + Platform: platformType, + Strace: *strace, + StraceLogSize: *straceLogSize, + WatchdogAction: wa, + PanicSignal: *panicSignal, + ProfileEnable: *profile, + EnableRaw: *netRaw, + NumNetworkChannels: *numNetworkChannels, + Rootless: *rootless, + AlsoLogToStderr: *alsoLogToStderr, TestOnlyAllowRunAsCurrentUserWithoutChroot: *testOnlyAllowRunAsCurrentUserWithoutChroot, } |