@@ -1,7 +1,6 @@

 package chrootarchive

 import (

-	"bytes"

 	"encoding/json"

 	"flag"

 	"fmt"

@@ -9,7 +8,6 @@ import (

 	"os"

 	"path/filepath"

 	"runtime"

-	"strings"

 	"syscall"

 	"github.com/docker/docker/pkg/archive"

@@ -28,11 +26,14 @@ func chroot(path string) error {

 func untar() {

 	runtime.LockOSThread()

 	flag.Parse()

-	if err := chroot(flag.Arg(0)); err != nil {

+

+	var options *archive.TarOptions

+

+	if err := json.Unmarshal([]byte(os.Getenv("OPT")), &options); err != nil {

 		fatal(err)

 	}

-	var options *archive.TarOptions

-	if err := json.NewDecoder(strings.NewReader(flag.Arg(1))).Decode(&options); err != nil {

+

+	if err := chroot(flag.Arg(0)); err != nil {

 		fatal(err)

 	}

 	if err := archive.Unpack(os.Stdin, "/", options); err != nil {

@@ -54,27 +55,32 @@ func Untar(tarArchive io.Reader, dest string, options *archive.TarOptions) error

 		options.ExcludePatterns = []string{}

 	}

-	var (

-		buf bytes.Buffer

-		enc = json.NewEncoder(&buf)

-	)

-	if err := enc.Encode(options); err != nil {

-		return fmt.Errorf("Untar json encode: %v", err)

-	}

+	dest = filepath.Clean(dest)

 	if _, err := os.Stat(dest); os.IsNotExist(err) {

 		if err := os.MkdirAll(dest, 0777); err != nil {

 			return err

 		}

 	}

-	dest = filepath.Clean(dest)

+

+	// We can't pass the exclude list directly via cmd line

+	// because we easily overrun the shell max argument list length

+	// when the full image list is passed (e.g. when this is used

+	// by `docker load`). Instead we will add the JSON marshalled

+	// and placed in the env, which has significantly larger

+	// max size

+	data, err := json.Marshal(options)

+	if err != nil {

+		return fmt.Errorf("Untar json encode: %v", err)

+	}

 	decompressedArchive, err := archive.DecompressStream(tarArchive)

 	if err != nil {

 		return err

 	}

 	defer decompressedArchive.Close()

-	cmd := reexec.Command("docker-untar", dest, buf.String())

+	cmd := reexec.Command("docker-untar", dest)

 	cmd.Stdin = decompressedArchive

+	cmd.Env = append(cmd.Env, fmt.Sprintf("OPT=%s", data))

 	out, err := cmd.CombinedOutput()

 	if err != nil {

 		return fmt.Errorf("Untar %s %s", err, out)