diff options
Diffstat (limited to 'runsc/boot')
-rw-r--r-- | runsc/boot/controller.go | 12 | ||||
-rw-r--r-- | runsc/boot/fds.go | 14 | ||||
-rw-r--r-- | runsc/boot/fs.go | 14 | ||||
-rw-r--r-- | runsc/boot/loader.go | 27 |
4 files changed, 44 insertions, 23 deletions
diff --git a/runsc/boot/controller.go b/runsc/boot/controller.go index b4594c8b0..ddba117c6 100644 --- a/runsc/boot/controller.go +++ b/runsc/boot/controller.go @@ -193,8 +193,10 @@ type StartArgs struct { // CID is the ID of the container to start. CID string - // FilePayload contains the file descriptor over which the sandbox will - // request files from its root filesystem. + // FilePayload contains, in order: + // * stdin, stdout, and stderr. + // * the file descriptor over which the sandbox will + // request files from its root filesystem. urpc.FilePayload } @@ -222,8 +224,8 @@ func (cm *containerManager) Start(args *StartArgs, _ *struct{}) error { if path.Clean(args.CID) != args.CID { return fmt.Errorf("container ID shouldn't contain directory traversals such as \"..\": %q", args.CID) } - if len(args.FilePayload.Files) == 0 { - return fmt.Errorf("start arguments must contain at least one file for the container root") + if len(args.FilePayload.Files) < 4 { + return fmt.Errorf("start arguments must contain stdin, stderr, and stdout followed by at least one file for the container root gofer") } err := cm.l.startContainer(cm.l.k, args.Spec, args.Conf, args.CID, args.FilePayload.Files) @@ -408,7 +410,7 @@ func (cm *containerManager) Restore(o *RestoreOpts, _ *struct{}) error { cm.l.k = k // Set up the restore environment. - fds := &fdDispenser{fds: cm.l.ioFDs} + fds := &fdDispenser{fds: cm.l.goferFDs} renv, err := createRestoreEnvironment(cm.l.spec, cm.l.conf, fds) if err != nil { return fmt.Errorf("error creating RestoreEnvironment: %v", err) diff --git a/runsc/boot/fds.go b/runsc/boot/fds.go index 9de5a78b1..92d641b68 100644 --- a/runsc/boot/fds.go +++ b/runsc/boot/fds.go @@ -16,7 +16,6 @@ package boot import ( "fmt" - "syscall" "gvisor.googlesource.com/gvisor/pkg/sentry/context" "gvisor.googlesource.com/gvisor/pkg/sentry/fs" @@ -28,15 +27,20 @@ import ( // createFDMap creates an fd map that contains stdin, stdout, and stderr. If // console is true, then ioctl calls will be passed through to the host fd. -func createFDMap(ctx context.Context, k *kernel.Kernel, l *limits.LimitSet, console bool) (*kernel.FDMap, error) { +// Upon success, createFDMap dups then closes stdioFDs. +func createFDMap(ctx context.Context, k *kernel.Kernel, l *limits.LimitSet, console bool, stdioFDs []int) (*kernel.FDMap, error) { + if len(stdioFDs) != 3 { + return nil, fmt.Errorf("stdioFDs should contain exactly 3 FDs (stdin, stdout, and stderr), but %d FDs received", len(stdioFDs)) + } + fdm := k.NewFDMap() defer fdm.DecRef() // Maps sandbox fd to host fd. fdMap := map[int]int{ - 0: syscall.Stdin, - 1: syscall.Stdout, - 2: syscall.Stderr, + 0: stdioFDs[0], + 1: stdioFDs[1], + 2: stdioFDs[2], } mounter := fs.FileOwnerFromContext(ctx) diff --git a/runsc/boot/fs.go b/runsc/boot/fs.go index 110f67de8..a97a4a3da 100644 --- a/runsc/boot/fs.go +++ b/runsc/boot/fs.go @@ -82,7 +82,7 @@ func (f *fdDispenser) empty() bool { // createMountNamespace creates a mount namespace containing the root filesystem // and all mounts. 'rootCtx' is used to walk directories to find mount points. -func createMountNamespace(userCtx context.Context, rootCtx context.Context, spec *specs.Spec, conf *Config, ioFDs []int) (*fs.MountNamespace, error) { +func createMountNamespace(userCtx context.Context, rootCtx context.Context, spec *specs.Spec, conf *Config, goferFDs []int) (*fs.MountNamespace, error) { mounts := compileMounts(spec) if conf.MultiContainer { // Create a tmpfs mount where we create and mount a root filesystem for @@ -92,7 +92,7 @@ func createMountNamespace(userCtx context.Context, rootCtx context.Context, spec Destination: ChildContainersDir, }) } - fds := &fdDispenser{fds: ioFDs} + fds := &fdDispenser{fds: goferFDs} rootInode, err := createRootMount(rootCtx, spec, conf, fds, mounts) if err != nil { return nil, fmt.Errorf("failed to create root mount: %v", err) @@ -587,14 +587,14 @@ func subtargets(root string, mnts []specs.Mount) []string { } // setFileSystemForProcess is used to set up the file system and amend the procArgs accordingly. -// procArgs are passed by reference and the FDMap field is modified. -func setFileSystemForProcess(procArgs *kernel.CreateProcessArgs, spec *specs.Spec, conf *Config, ioFDs []int, console bool, creds *auth.Credentials, ls *limits.LimitSet, k *kernel.Kernel, cid string) error { +// procArgs are passed by reference and the FDMap field is modified. It dups stdioFDs. +func setFileSystemForProcess(procArgs *kernel.CreateProcessArgs, spec *specs.Spec, conf *Config, stdioFDs, goferFDs []int, console bool, creds *auth.Credentials, ls *limits.LimitSet, k *kernel.Kernel, cid string) error { ctx := procArgs.NewContext(k) // Create the FD map, which will set stdin, stdout, and stderr. If // console is true, then ioctl calls will be passed through to the host // fd. - fdm, err := createFDMap(ctx, k, ls, console) + fdm, err := createFDMap(ctx, k, ls, console, stdioFDs) if err != nil { return fmt.Errorf("error importing fds: %v", err) } @@ -618,7 +618,7 @@ func setFileSystemForProcess(procArgs *kernel.CreateProcessArgs, spec *specs.Spe mns := k.RootMountNamespace() if mns == nil { // Create the virtual filesystem. - mns, err := createMountNamespace(ctx, rootCtx, spec, conf, ioFDs) + mns, err := createMountNamespace(ctx, rootCtx, spec, conf, goferFDs) if err != nil { return fmt.Errorf("error creating mounts: %v", err) } @@ -630,7 +630,7 @@ func setFileSystemForProcess(procArgs *kernel.CreateProcessArgs, spec *specs.Spe // Create the container's root filesystem mount. log.Infof("Creating new process in child container.") - fds := &fdDispenser{fds: append([]int{}, ioFDs...)} + fds := &fdDispenser{fds: append([]int{}, goferFDs...)} rootInode, err := createRootMount(rootCtx, spec, conf, fds, nil) if err != nil { return fmt.Errorf("error creating filesystem for container: %v", err) diff --git a/runsc/boot/loader.go b/runsc/boot/loader.go index f906c9f95..e47eced18 100644 --- a/runsc/boot/loader.go +++ b/runsc/boot/loader.go @@ -78,8 +78,11 @@ type Loader struct { watchdog *watchdog.Watchdog - // ioFDs are the FDs that attach the sandbox to the gofers. - ioFDs []int + // stdioFDs contains stdin, stdout, and stderr. + stdioFDs []int + + // goferFDs are the FDs that attach the sandbox to the gofers. + goferFDs []int // spec is the base configuration for the root container. spec *specs.Spec @@ -139,7 +142,7 @@ func init() { // New initializes a new kernel loader configured by spec. // New also handles setting up a kernel for restoring a container. -func New(spec *specs.Spec, conf *Config, controllerFD, deviceFD int, ioFDs []int, console bool) (*Loader, error) { +func New(spec *specs.Spec, conf *Config, controllerFD, deviceFD int, goferFDs []int, console bool) (*Loader, error) { if err := usage.Init(); err != nil { return nil, fmt.Errorf("Error setting up memory usage: %v", err) } @@ -278,7 +281,8 @@ func New(spec *specs.Spec, conf *Config, controllerFD, deviceFD int, ioFDs []int conf: conf, console: console, watchdog: watchdog, - ioFDs: ioFDs, + stdioFDs: []int{syscall.Stdin, syscall.Stdout, syscall.Stderr}, + goferFDs: goferFDs, spec: spec, startSignalForwarding: startSignalForwarding, rootProcArgs: procArgs, @@ -390,7 +394,8 @@ func (l *Loader) run() error { &l.rootProcArgs, l.spec, l.conf, - l.ioFDs, + l.stdioFDs, + l.goferFDs, l.console, l.rootProcArgs.Credentials, l.rootProcArgs.Limits, @@ -474,11 +479,14 @@ func (l *Loader) startContainer(k *kernel.Kernel, spec *specs.Spec, conf *Config ioFDs = append(ioFDs, fd) } + stdioFDs := ioFDs[:3] + goferFDs := ioFDs[3:] if err := setFileSystemForProcess( &procArgs, spec, conf, - ioFDs, + stdioFDs, + goferFDs, false, creds, procArgs.Limits, @@ -487,6 +495,13 @@ func (l *Loader) startContainer(k *kernel.Kernel, spec *specs.Spec, conf *Config return fmt.Errorf("failed to create new process: %v", err) } + // setFileSystemForProcess dup'd stdioFDs, so we can close them. + for i, fd := range stdioFDs { + if err := syscall.Close(fd); err != nil { + return fmt.Errorf("failed to close stdioFD #%d: %v", i, fd) + } + } + ctx := procArgs.NewContext(l.k) mns := k.RootMountNamespace() if err := setExecutablePath(ctx, mns, &procArgs); err != nil { |