@@ -22,6 +22,7 @@ import (

 	"github.com/docker/docker/pkg/fileutils"

 	"github.com/docker/docker/pkg/pools"

 	"github.com/docker/docker/pkg/promise"

+	"github.com/docker/docker/pkg/symlink"

 	"github.com/docker/docker/pkg/system"

 )

@@ -292,11 +293,23 @@ func createTarFile(path, extractDir string, hdr *tar.Header, reader io.Reader, L

 		}

 	case tar.TypeLink:

-		if err := os.Link(filepath.Join(extractDir, hdr.Linkname), path); err != nil {

+		targetPath := filepath.Join(extractDir, hdr.Linkname)

+		// check for hardlink breakout

+		if !strings.HasPrefix(targetPath, extractDir) {

+			return breakoutError(fmt.Errorf("invalid hardlink %q -> %q", targetPath, hdr.Linkname))

+		}

+		if err := os.Link(targetPath, path); err != nil {

 			return err

 		}

 	case tar.TypeSymlink:

+		// check for symlink breakout

+		if _, err := symlink.FollowSymlinkInScope(filepath.Join(filepath.Dir(path), hdr.Linkname), extractDir); err != nil {

+			if _, ok := err.(symlink.ErrBreakout); ok {

+				return breakoutError(fmt.Errorf("invalid symlink %q -> %q", path, hdr.Linkname))

+			}

+			return err

+		}

 		if err := os.Symlink(hdr.Linkname, path); err != nil {

 			return err

 		}

@@ -456,6 +469,8 @@ func TarWithOptions(srcPath string, options *TarOptions) (io.ReadCloser, error)

 //  identity (uncompressed), gzip, bzip2, xz.

 // FIXME: specify behavior when target path exists vs. doesn't exist.

 func Untar(archive io.Reader, dest string, options *TarOptions) error {

+	dest = filepath.Clean(dest)

+

 	if options == nil {

 		options = &TarOptions{}

 	}

@@ -493,6 +508,7 @@ loop:

 		}

 		// Normalize name, for safety and for a simple is-root check

+		// This keeps "../" as-is, but normalizes "/../" to "/"

 		hdr.Name = filepath.Clean(hdr.Name)

 		for _, exclude := range options.Excludes {

@@ -513,7 +529,11 @@ loop:

 			}

 		}

+		// Prevent symlink breakout

 		path := filepath.Join(dest, hdr.Name)

+		if !strings.HasPrefix(path, dest) {

+			return breakoutError(fmt.Errorf("%q is outside of %q", path, dest))

+		}

 		// If path exits we almost always just want to remove and replace it

 		// The only exception is when it is a directory *and* the file from

@@ -10,6 +10,8 @@ import (

 const maxLoopCounter = 100

+type ErrBreakout error

+

 // FollowSymlink will follow an existing link and scope it to the root

 // path provided.

 // The role of this function is to return an absolute path in the root

@@ -34,7 +36,7 @@ func FollowSymlinkInScope(link, root string) (string, error) {

 	}

 	if !strings.HasPrefix(filepath.Dir(link), root) {

-		return "", fmt.Errorf("%s is not within %s", link, root)

+		return "", ErrBreakout(fmt.Errorf("%s is not within %s", link, root))

 	}

 	prev := "/"