diff options
Diffstat (limited to 'runsc/sandbox')
-rw-r--r-- | runsc/sandbox/BUILD | 1 | ||||
-rw-r--r-- | runsc/sandbox/network.go | 30 | ||||
-rw-r--r-- | runsc/sandbox/sandbox.go | 198 |
3 files changed, 169 insertions, 60 deletions
diff --git a/runsc/sandbox/BUILD b/runsc/sandbox/BUILD index c95d50294..035dcd3e3 100644 --- a/runsc/sandbox/BUILD +++ b/runsc/sandbox/BUILD @@ -13,6 +13,7 @@ go_library( "//runsc:__subpackages__", ], deps = [ + "//pkg/cleanup", "//pkg/control/client", "//pkg/control/server", "//pkg/log", diff --git a/runsc/sandbox/network.go b/runsc/sandbox/network.go index 99e143696..209bfdb20 100644 --- a/runsc/sandbox/network.go +++ b/runsc/sandbox/network.go @@ -21,7 +21,6 @@ import ( "path/filepath" "runtime" "strconv" - "strings" "syscall" specs "github.com/opencontainers/runtime-spec/specs-go" @@ -63,7 +62,7 @@ func setupNetwork(conn *urpc.Client, pid int, spec *specs.Spec, conf *boot.Confi // Build the path to the net namespace of the sandbox process. // This is what we will copy. nsPath := filepath.Join("/proc", strconv.Itoa(pid), "ns/net") - if err := createInterfacesAndRoutesFromNS(conn, nsPath, conf.HardwareGSO, conf.SoftwareGSO, conf.NumNetworkChannels); err != nil { + if err := createInterfacesAndRoutesFromNS(conn, nsPath, conf.HardwareGSO, conf.SoftwareGSO, conf.NumNetworkChannels, conf.QDisc); err != nil { return fmt.Errorf("creating interfaces from net namespace %q: %v", nsPath, err) } case boot.NetworkHost: @@ -75,30 +74,8 @@ func setupNetwork(conn *urpc.Client, pid int, spec *specs.Spec, conf *boot.Confi } func createDefaultLoopbackInterface(conn *urpc.Client) error { - link := boot.LoopbackLink{ - Name: "lo", - Addresses: []net.IP{ - net.IP("\x7f\x00\x00\x01"), - net.IPv6loopback, - }, - Routes: []boot.Route{ - { - Destination: net.IPNet{ - - IP: net.IPv4(0x7f, 0, 0, 0), - Mask: net.IPv4Mask(0xff, 0, 0, 0), - }, - }, - { - Destination: net.IPNet{ - IP: net.IPv6loopback, - Mask: net.IPMask(strings.Repeat("\xff", net.IPv6len)), - }, - }, - }, - } if err := conn.Call(boot.NetworkCreateLinksAndRoutes, &boot.CreateLinksAndRoutesArgs{ - LoopbackLinks: []boot.LoopbackLink{link}, + LoopbackLinks: []boot.LoopbackLink{boot.DefaultLoopbackLink}, }, nil); err != nil { return fmt.Errorf("creating loopback link and routes: %v", err) } @@ -138,7 +115,7 @@ func isRootNS() (bool, error) { // createInterfacesAndRoutesFromNS scrapes the interface and routes from the // net namespace with the given path, creates them in the sandbox, and removes // them from the host. -func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, hardwareGSO bool, softwareGSO bool, numNetworkChannels int) error { +func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, hardwareGSO bool, softwareGSO bool, numNetworkChannels int, qDisc boot.QueueingDiscipline) error { // Join the network namespace that we will be copying. restore, err := joinNetNS(nsPath) if err != nil { @@ -224,6 +201,7 @@ func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, hardwareG MTU: iface.MTU, Routes: routes, NumChannels: numNetworkChannels, + QDisc: qDisc, } // Get the link for the interface. diff --git a/runsc/sandbox/sandbox.go b/runsc/sandbox/sandbox.go index ec72bdbfd..6e1a2af25 100644 --- a/runsc/sandbox/sandbox.go +++ b/runsc/sandbox/sandbox.go @@ -18,16 +18,19 @@ package sandbox import ( "context" "fmt" + "io" "math" "os" "os/exec" "strconv" + "strings" "syscall" "time" "github.com/cenkalti/backoff" specs "github.com/opencontainers/runtime-spec/specs-go" "github.com/syndtr/gocapability/capability" + "gvisor.dev/gvisor/pkg/cleanup" "gvisor.dev/gvisor/pkg/control/client" "gvisor.dev/gvisor/pkg/control/server" "gvisor.dev/gvisor/pkg/log" @@ -117,7 +120,7 @@ func New(conf *boot.Config, args *Args) (*Sandbox, error) { s := &Sandbox{ID: args.ID, Cgroup: args.Cgroup} // The Cleanup object cleans up partially created sandboxes when an error // occurs. Any errors occurring during cleanup itself are ignored. - c := specutils.MakeCleanup(func() { + c := cleanup.Make(func() { err := s.destroy() log.Warningf("error destroying sandbox: %v", err) }) @@ -142,7 +145,19 @@ func New(conf *boot.Config, args *Args) (*Sandbox, error) { // Wait until the sandbox has booted. b := make([]byte, 1) if l, err := clientSyncFile.Read(b); err != nil || l != 1 { - return nil, fmt.Errorf("waiting for sandbox to start: %v", err) + err := fmt.Errorf("waiting for sandbox to start: %v", err) + // If the sandbox failed to start, it may be because the binary + // permissions were incorrect. Check the bits and return a more helpful + // error message. + // + // NOTE: The error message is checked because error types are lost over + // rpc calls. + if strings.Contains(err.Error(), io.EOF.Error()) { + if permsErr := checkBinaryPermissions(conf); permsErr != nil { + return nil, fmt.Errorf("%v: %v", err, permsErr) + } + } + return nil, err } c.Release() @@ -369,8 +384,24 @@ func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncF cmd.Args = append(cmd.Args, "--debug-log-fd="+strconv.Itoa(nextFD)) nextFD++ } + if conf.PanicLog != "" { + test := "" + if len(conf.TestOnlyTestNameEnv) != 0 { + // Fetch test name if one is provided and the test only flag was set. + if t, ok := specutils.EnvVar(args.Spec.Process.Env, conf.TestOnlyTestNameEnv); ok { + test = t + } + } - cmd.Args = append(cmd.Args, "--panic-signal="+strconv.Itoa(int(syscall.SIGTERM))) + panicLogFile, err := specutils.DebugLogFile(conf.PanicLog, "panic", test) + if err != nil { + return fmt.Errorf("opening debug log file in %q: %v", conf.PanicLog, err) + } + defer panicLogFile.Close() + cmd.ExtraFiles = append(cmd.ExtraFiles, panicLogFile) + cmd.Args = append(cmd.Args, "--panic-log-fd="+strconv.Itoa(nextFD)) + nextFD++ + } // Add the "boot" command to the args. // @@ -416,9 +447,13 @@ func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncF nextFD++ } - // If the platform needs a device FD we must pass it in. - if deviceFile, err := deviceFileForPlatform(conf.Platform); err != nil { + gPlatform, err := platform.Lookup(conf.Platform) + if err != nil { return err + } + + if deviceFile, err := gPlatform.OpenDevice(); err != nil { + return fmt.Errorf("opening device file for platform %q: %v", gPlatform, err) } else if deviceFile != nil { defer deviceFile.Close() cmd.ExtraFiles = append(cmd.ExtraFiles, deviceFile) @@ -426,6 +461,12 @@ func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncF nextFD++ } + // TODO(b/151157106): syscall tests fail by timeout if asyncpreemptoff + // isn't set. + if conf.Platform == "kvm" { + cmd.Env = append(cmd.Env, "GODEBUG=asyncpreemptoff=1") + } + // The current process' stdio must be passed to the application via the // --stdio-fds flag. The stdio of the sandbox process itself must not // be connected to the same FDs, otherwise we risk leaking sandbox @@ -503,7 +544,7 @@ func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncF {Type: specs.UTSNamespace}, } - if conf.Platform == platforms.Ptrace { + if gPlatform.Requirements().RequiresCurrentPIDNS { // TODO(b/75837838): Also set a new PID namespace so that we limit // access to other host processes. log.Infof("Sandbox will be started in the current PID namespace") @@ -564,45 +605,32 @@ func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncF nss = append(nss, specs.LinuxNamespace{Type: specs.UserNamespace}) cmd.Args = append(cmd.Args, "--setup-root") + const nobody = 65534 if conf.Rootless { - log.Infof("Rootless mode: sandbox will run as root inside user namespace, mapped to the current user, uid: %d, gid: %d", os.Getuid(), os.Getgid()) + log.Infof("Rootless mode: sandbox will run as nobody inside user namespace, mapped to the current user, uid: %d, gid: %d", os.Getuid(), os.Getgid()) cmd.SysProcAttr.UidMappings = []syscall.SysProcIDMap{ { - ContainerID: 0, + ContainerID: nobody, HostID: os.Getuid(), Size: 1, }, } cmd.SysProcAttr.GidMappings = []syscall.SysProcIDMap{ { - ContainerID: 0, + ContainerID: nobody, HostID: os.Getgid(), Size: 1, }, } - cmd.SysProcAttr.Credential = &syscall.Credential{Uid: 0, Gid: 0} } else { // Map nobody in the new namespace to nobody in the parent namespace. // // A sandbox process will construct an empty - // root for itself, so it has to have the CAP_SYS_ADMIN - // capability. - // - // FIXME(b/122554829): The current implementations of - // os/exec doesn't allow to set ambient capabilities if - // a process is started in a new user namespace. As a - // workaround, we start the sandbox process with the 0 - // UID and then it constructs a chroot and sets UID to - // nobody. https://github.com/golang/go/issues/2315 - const nobody = 65534 + // root for itself, so it has to have + // CAP_SYS_ADMIN and CAP_SYS_CHROOT capabilities. cmd.SysProcAttr.UidMappings = []syscall.SysProcIDMap{ { - ContainerID: 0, - HostID: nobody - 1, - Size: 1, - }, - { ContainerID: nobody, HostID: nobody, Size: 1, @@ -615,11 +643,11 @@ func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncF Size: 1, }, } - - // Set credentials to run as user and group nobody. - cmd.SysProcAttr.Credential = &syscall.Credential{Uid: 0, Gid: nobody} } + // Set credentials to run as user and group nobody. + cmd.SysProcAttr.Credential = &syscall.Credential{Uid: nobody, Gid: nobody} + cmd.SysProcAttr.AmbientCaps = append(cmd.SysProcAttr.AmbientCaps, uintptr(capability.CAP_SYS_ADMIN), uintptr(capability.CAP_SYS_CHROOT)) } else { return fmt.Errorf("can't run sandbox process as user nobody since we don't have CAP_SETUID or CAP_SETGID") } @@ -677,6 +705,13 @@ func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncF nextFD++ } + if args.Attached { + // Kill sandbox if parent process exits in attached mode. + cmd.SysProcAttr.Pdeathsig = syscall.SIGKILL + // Tells boot that any process it creates must have pdeathsig set. + cmd.Args = append(cmd.Args, "--attached") + } + // Add container as the last argument. cmd.Args = append(cmd.Args, s.ID) @@ -685,15 +720,22 @@ func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncF log.Debugf("Donating FD %d: %q", i+3, f.Name()) } - if args.Attached { - // Kill sandbox if parent process exits in attached mode. - cmd.SysProcAttr.Pdeathsig = syscall.SIGKILL - } - log.Debugf("Starting sandbox: %s %v", binPath, cmd.Args) log.Debugf("SysProcAttr: %+v", cmd.SysProcAttr) if err := specutils.StartInNS(cmd, nss); err != nil { - return fmt.Errorf("Sandbox: %v", err) + err := fmt.Errorf("starting sandbox: %v", err) + // If the sandbox failed to start, it may be because the binary + // permissions were incorrect. Check the bits and return a more helpful + // error message. + // + // NOTE: The error message is checked because error types are lost over + // rpc calls. + if strings.Contains(err.Error(), syscall.EACCES.Error()) { + if permsErr := checkBinaryPermissions(conf); permsErr != nil { + return fmt.Errorf("%v: %v", err, permsErr) + } + } + return err } s.child = true s.Pid = cmd.Process.Pid @@ -972,6 +1014,66 @@ func (s *Sandbox) StopCPUProfile() error { return nil } +// GoroutineProfile writes a goroutine profile to the given file. +func (s *Sandbox) GoroutineProfile(f *os.File) error { + log.Debugf("Goroutine profile %q", s.ID) + conn, err := s.sandboxConnect() + if err != nil { + return err + } + defer conn.Close() + + opts := control.ProfileOpts{ + FilePayload: urpc.FilePayload{ + Files: []*os.File{f}, + }, + } + if err := conn.Call(boot.GoroutineProfile, &opts, nil); err != nil { + return fmt.Errorf("getting sandbox %q goroutine profile: %v", s.ID, err) + } + return nil +} + +// BlockProfile writes a block profile to the given file. +func (s *Sandbox) BlockProfile(f *os.File) error { + log.Debugf("Block profile %q", s.ID) + conn, err := s.sandboxConnect() + if err != nil { + return err + } + defer conn.Close() + + opts := control.ProfileOpts{ + FilePayload: urpc.FilePayload{ + Files: []*os.File{f}, + }, + } + if err := conn.Call(boot.BlockProfile, &opts, nil); err != nil { + return fmt.Errorf("getting sandbox %q block profile: %v", s.ID, err) + } + return nil +} + +// MutexProfile writes a mutex profile to the given file. +func (s *Sandbox) MutexProfile(f *os.File) error { + log.Debugf("Mutex profile %q", s.ID) + conn, err := s.sandboxConnect() + if err != nil { + return err + } + defer conn.Close() + + opts := control.ProfileOpts{ + FilePayload: urpc.FilePayload{ + Files: []*os.File{f}, + }, + } + if err := conn.Call(boot.MutexProfile, &opts, nil); err != nil { + return fmt.Errorf("getting sandbox %q mutex profile: %v", s.ID, err) + } + return nil +} + // StartTrace start trace writing to the given file. func (s *Sandbox) StartTrace(f *os.File) error { log.Debugf("Trace start %q", s.ID) @@ -1096,3 +1198,31 @@ func deviceFileForPlatform(name string) (*os.File, error) { } return f, nil } + +// checkBinaryPermissions verifies that the required binary bits are set on +// the runsc executable. +func checkBinaryPermissions(conf *boot.Config) error { + // All platforms need the other exe bit + neededBits := os.FileMode(0001) + if conf.Platform == platforms.Ptrace { + // Ptrace needs the other read bit + neededBits |= os.FileMode(0004) + } + + exePath, err := os.Executable() + if err != nil { + return fmt.Errorf("getting exe path: %v", err) + } + + // Check the permissions of the runsc binary and print an error if it + // doesn't match expectations. + info, err := os.Stat(exePath) + if err != nil { + return fmt.Errorf("stat file: %v", err) + } + + if info.Mode().Perm()&neededBits != neededBits { + return fmt.Errorf(specutils.FaqErrorMsg("runsc-perms", fmt.Sprintf("%s does not have the correct permissions", exePath))) + } + return nil +} |