refactor to add unit tests

pkg/commands/commands.go

@@ -17,7 +17,6 @@ limitations under the License.
 package commands
 
 import (
-	"github.com/GoogleContainerTools/kaniko/pkg/constants"
 	"github.com/GoogleContainerTools/kaniko/pkg/dockerfile"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/moby/buildkit/frontend/dockerfile/instructions"
@@ -25,12 +24,6 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
-var RootDir string
-
-func init() {
-	RootDir = constants.RootDir
-}
-
 type CurrentCacheKey func() (string, error)
 
 type DockerCommand interface {

pkg/commands/copy.go

@@ -22,7 +22,7 @@ import (
 	"path/filepath"
 	"strings"
 
-	"github.com/GoogleContainerTools/kaniko/pkg/constants"
+	kConfig "github.com/GoogleContainerTools/kaniko/pkg/config"
 	"github.com/moby/buildkit/frontend/dockerfile/instructions"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
@@ -47,7 +47,7 @@ type CopyCommand struct {
 func (c *CopyCommand) ExecuteCommand(config *v1.Config, buildArgs *dockerfile.BuildArgs) error {
 	// Resolve from
 	if c.cmd.From != "" {
-		c.buildcontext = filepath.Join(constants.KanikoDir, c.cmd.From)
+		c.buildcontext = filepath.Join(kConfig.KanikoDir, c.cmd.From)
 	}
 
 	replacementEnvs := buildArgs.ReplacementEnvs(config.Env)
@@ -74,7 +74,7 @@ func (c *CopyCommand) ExecuteCommand(config *v1.Config, buildArgs *dockerfile.Bu
 		}
 		cwd := config.WorkingDir
 		if cwd == "" {
-			cwd = constants.RootDir
+			cwd = kConfig.RootDir
 		}
 
 		destPath, err := util.DestinationFilepath(fullPath, dest, cwd)
@@ -191,7 +191,7 @@ func (cr *CachingCopyCommand) ExecuteCommand(config *v1.Config, buildArgs *docke
 	cr.layer = layers[0]
 	cr.readSuccess = true
 
-	cr.extractedFiles, err = util.GetFSFromLayers(RootDir, layers, util.ExtractFunc(cr.extractFn), util.IncludeWhiteout())
+	cr.extractedFiles, err = util.GetFSFromLayers(kConfig.RootDir, layers, util.ExtractFunc(cr.extractFn), util.IncludeWhiteout())
 
 	logrus.Debugf("extractedFiles: %s", cr.extractedFiles)
 	if err != nil {

pkg/commands/copy_test.go

@@ -405,7 +405,6 @@ func TestCopyCommand_ExecuteCommand_Extended(t *testing.T) {
 		if err := os.MkdirAll(dir, 0777); err != nil {
 			t.Fatal(err)
 		}
-
 		file := filepath.Join(dir, "bam.txt")
 
 		if err := ioutil.WriteFile(file, []byte("meow"), 0777); err != nil {
@@ -418,6 +417,7 @@ func TestCopyCommand_ExecuteCommand_Extended(t *testing.T) {
 		if err := os.Symlink("dam.txt", filepath.Join(dir, "sym.link")); err != nil {
 			t.Fatal(err)
 		}
+
 		return testDir, filepath.Base(dir)
 	}
 
@@ -922,4 +922,42 @@ func TestCopyCommand_ExecuteCommand_Extended(t *testing.T) {
 			testutil.CheckNoError(t, err)
 		}
 	})
+
+	t.Run("copy src dir with relative symlinks in a dir", func(t *testing.T) {
+		testDir, srcDir := setupDirs(t)
+		defer os.RemoveAll(testDir)
+
+		// Make another dir inside bar with a relative symlink
+		dir := filepath.Join(testDir, srcDir, "another")
+		if err := os.MkdirAll(dir, 0777); err != nil {
+			t.Fatal(err)
+		}
+		os.Symlink("../bam.txt", filepath.Join(dir, "bam_relative.txt"))
+
+		dest := filepath.Join(testDir, "copy")
+		cmd := CopyCommand{
+			cmd: &instructions.CopyCommand{
+				SourcesAndDest: []string{srcDir, dest},
+			},
+			buildcontext: testDir,
+		}
+
+		cfg := &v1.Config{
+			Cmd:        nil,
+			Env:        []string{},
+			WorkingDir: testDir,
+		}
+		err := cmd.ExecuteCommand(cfg, dockerfile.NewBuildArgs([]string{}))
+		testutil.CheckNoError(t, err)
+		actual, err := ioutil.ReadDir(filepath.Join(dest, "another"))
+		if err != nil {
+			t.Fatal(err)
+		}
+		testutil.CheckDeepEqual(t, "bam_relative.txt", actual[0].Name())
+		linkName, err := os.Readlink(filepath.Join(dest, "another", "bam_relative.txt"))
+		if err != nil {
+			t.Fatal(err)
+		}
+		testutil.CheckDeepEqual(t, "../bam.txt", linkName)
+	})
 }

pkg/commands/run.go

@@ -24,6 +24,7 @@ import (
 	"strings"
 	"syscall"
 
+	kConfig "github.com/GoogleContainerTools/kaniko/pkg/config"
 	"github.com/GoogleContainerTools/kaniko/pkg/constants"
 	"github.com/GoogleContainerTools/kaniko/pkg/dockerfile"
 	"github.com/GoogleContainerTools/kaniko/pkg/util"
@@ -202,7 +203,7 @@ func (cr *CachingRunCommand) ExecuteCommand(config *v1.Config, buildArgs *docker
 	cr.readSuccess = true
 
 	cr.extractedFiles, err = util.GetFSFromLayers(
-		constants.RootDir,
+		kConfig.RootDir,
 		layers,
 		util.ExtractFunc(cr.extractFn),
 		util.IncludeWhiteout(),

pkg/config/init.go

@@ -0,0 +1,31 @@
+/*
+Copyright 2020 Google LLC
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package config
+
+import (
+	"github.com/GoogleContainerTools/kaniko/pkg/constants"
+)
+
+var RootDir string
+var KanikoDir string
+var WhitelistPath string
+
+func init() {
+	RootDir = constants.RootDir
+	KanikoDir = constants.KanikoDir
+	WhitelistPath = constants.WhitelistPath
+}

pkg/executor/build.go

@@ -97,7 +97,7 @@ func newStageBuilder(opts *config.KanikoOptions, stage config.KanikoStage, cross
 		return nil, err
 	}
 	l := snapshot.NewLayeredMap(hasher, util.CacheHasher())
-	snapshotter := snapshot.NewSnapshotter(l, constants.RootDir)
+	snapshotter := snapshot.NewSnapshotter(l, config.RootDir)
 
 	digest, err := sourceImage.Digest()
 	if err != nil {
@@ -298,7 +298,7 @@ func (s *stageBuilder) build() error {
 	if shouldUnpack {
 		t := timing.Start("FS Unpacking")
 
-		if _, err := util.GetFSFromImage(constants.RootDir, s.image, util.ExtractFile); err != nil {
+		if _, err := util.GetFSFromImage(config.RootDir, s.image, util.ExtractFile); err != nil {
 			return errors.Wrap(err, "failed to get filesystem from image")
 		}
 
@@ -307,7 +307,7 @@ func (s *stageBuilder) build() error {
 		logrus.Info("Skipping unpacking as no commands require it.")
 	}
 
-	if err := util.DetectFilesystemWhitelist(constants.WhitelistPath); err != nil {
+	if err := util.DetectFilesystemWhitelist(config.WhitelistPath); err != nil {
 		return errors.Wrap(err, "failed to check filesystem whitelist")
 	}
 
@@ -524,7 +524,6 @@ func CalculateDependencies(opts *config.KanikoOptions) (map[int][]string, error)
 					if err != nil {
 						return nil, err
 					}
-
 					depGraph[i] = append(depGraph[i], resolved[0:len(resolved)-1]...)
 				}
 			case *instructions.EnvCommand:
@@ -629,20 +628,23 @@ func DoBuild(opts *config.KanikoOptions) (v1.Image, error) {
 		if err != nil {
 			return nil, err
 		}
-		dstDir := filepath.Join(constants.KanikoDir, strconv.Itoa(index))
+		dstDir := filepath.Join(config.KanikoDir, strconv.Itoa(index))
 		if err := os.MkdirAll(dstDir, 0644); err != nil {
-			return nil, err
+			return nil, errors.Wrap(err,
+				fmt.Sprintf("to create workspace for stage %s",
+					stageIdxToDigest[strconv.Itoa(index)],
+				))
 		}
 		for _, p := range filesToSave {
 			logrus.Infof("Saving file %s for later use", p)
-			if err := util.CopyFileOrSymlink(p, dstDir); err != nil {
+			if err := util.CopyFileOrSymlink(p, dstDir, config.RootDir); err != nil {
-				return nil, err
+				return nil, errors.Wrap(err, "could not save file")
 			}
 		}
 
 		// Delete the filesystem
 		if err := util.DeleteFilesystem(); err != nil {
-			return nil, err
+			return nil, errors.Wrap(err, fmt.Sprintf("deleting file system after satge %d", index))
 		}
 	}
 
@@ -653,17 +655,15 @@ func DoBuild(opts *config.KanikoOptions) (v1.Image, error) {
 // If a file is a symlink, it also returns the target file.
 func filesToSave(deps []string) ([]string, error) {
 	srcFiles := []string{}
-	for _, src := range deps {
+	srcs, err := util.ResolveSources(deps, config.RootDir)
-		srcs, err := filepath.Glob(src)
+	if err != nil {
-		if err != nil {
+		return nil, errors.Wrap(err, "resolving sources to save")
-			return nil, err
+	}
-		}
+	for _, f := range srcs {
-		for _, f := range srcs {
+		if link, err := util.EvalSymLink(f); err == nil {
-			if link, err := util.EvalSymLink(f); err == nil {
+			srcFiles = append(srcFiles, link)
-				srcFiles = append(srcFiles, link)
-			}
-			srcFiles = append(srcFiles, f)
 		}
+		srcFiles = append(srcFiles, f)
 	}
 	return srcFiles, nil
 }
@@ -717,7 +717,7 @@ func fetchExtraStages(stages []config.KanikoStage, opts *config.KanikoOptions) e
 func extractImageToDependencyDir(name string, image v1.Image) error {
 	t := timing.Start("Extracting Image to Dependency Dir")
 	defer timing.DefaultRun.Stop(t)
-	dependencyDir := filepath.Join(constants.KanikoDir, name)
+	dependencyDir := filepath.Join(config.KanikoDir, name)
 	if err := os.MkdirAll(dependencyDir, 0755); err != nil {
 		return err
 	}

pkg/executor/build_test.go

@@ -1129,9 +1129,9 @@ COPY %s bar.txt
 			for key, value := range tc.args {
 				sb.args.AddArg(key, &value)
 			}
-			tmp := commands.RootDir
+			tmp := config.RootDir
 			if tc.rootDir != "" {
-				commands.RootDir = tc.rootDir
+				config.RootDir = tc.rootDir
 			}
 			err := sb.build()
 			if err != nil {
@@ -1141,7 +1141,7 @@ COPY %s bar.txt
 			assertCacheKeys(t, tc.expectedCacheKeys, lc.receivedKeys, "receive")
 			assertCacheKeys(t, tc.pushedCacheKeys, keys, "push")
 
-			commands.RootDir = tmp
+			config.RootDir = tmp
 
 		})
 	}

pkg/executor/copy_multistage_test.go

@@ -0,0 +1,186 @@
+/*
+Copyright 2020 Google LLC
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package executor
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/GoogleContainerTools/kaniko/pkg/config"
+	"github.com/GoogleContainerTools/kaniko/pkg/constants"
+	"github.com/GoogleContainerTools/kaniko/testutil"
+)
+
+func TestCopyCommand_Multistage(t *testing.T) {
+	t.Run("copy a file across multistage", func(t *testing.T) {
+		testDir, fn := setupMultistageTests(t)
+		defer fn()
+		dockerFile := fmt.Sprintf(`
+FROM scratch as first
+COPY foo/bam.txt copied/
+ENV test test
+
+From scratch as second
+COPY --from=first copied/bam.txt output/bam.txt`)
+		ioutil.WriteFile(filepath.Join(testDir, "workspace", "Dockerfile"), []byte(dockerFile), 0755)
+		opts := &config.KanikoOptions{
+			DockerfilePath: filepath.Join(testDir, "workspace", "Dockerfile"),
+			SrcContext:     filepath.Join(testDir, "workspace"),
+			SnapshotMode:   constants.SnapshotModeFull,
+		}
+		_, err := DoBuild(opts)
+		testutil.CheckNoError(t, err)
+		// Check Image has one layer bam.txt
+		files, err := ioutil.ReadDir(filepath.Join(testDir, "output"))
+		if err != nil {
+			t.Fatal(err)
+		}
+		testutil.CheckDeepEqual(t, 1, len(files))
+		testutil.CheckDeepEqual(t, files[0].Name(), "bam.txt")
+
+	})
+
+	t.Run("copy a file across multistage into a directory", func(t *testing.T) {
+		testDir, fn := setupMultistageTests(t)
+		defer fn()
+		dockerFile := fmt.Sprintf(`
+FROM scratch as first
+COPY foo/bam.txt copied/
+ENV test test
+
+From scratch as second
+COPY --from=first copied/bam.txt output/`)
+		ioutil.WriteFile(filepath.Join(testDir, "workspace", "Dockerfile"), []byte(dockerFile), 0755)
+		opts := &config.KanikoOptions{
+			DockerfilePath: filepath.Join(testDir, "workspace", "Dockerfile"),
+			SrcContext:     filepath.Join(testDir, "workspace"),
+			SnapshotMode:   constants.SnapshotModeFull,
+		}
+		_, err := DoBuild(opts)
+		files, err := ioutil.ReadDir(filepath.Join(testDir, "output"))
+		if err != nil {
+			t.Fatal(err)
+		}
+		testutil.CheckDeepEqual(t, 1, len(files))
+		testutil.CheckDeepEqual(t, files[0].Name(), "bam.txt")
+	})
+	t.Run("copy directory across multistage into a directory", func(t *testing.T) {
+		testDir, fn := setupMultistageTests(t)
+		defer fn()
+		dockerFile := fmt.Sprintf(`
+FROM scratch as first
+COPY foo copied
+ENV test test
+
+From scratch as second
+COPY --from=first copied another`)
+		ioutil.WriteFile(filepath.Join(testDir, "workspace", "Dockerfile"), []byte(dockerFile), 0755)
+		opts := &config.KanikoOptions{
+			DockerfilePath: filepath.Join(testDir, "workspace", "Dockerfile"),
+			SrcContext:     filepath.Join(testDir, "workspace"),
+			SnapshotMode:   constants.SnapshotModeFull,
+		}
+		_, err := DoBuild(opts)
+		testutil.CheckNoError(t, err)
+		// Check Image has one layer bam.txt
+		files, err := ioutil.ReadDir(filepath.Join(testDir, "another"))
+		if err != nil {
+			t.Fatal(err)
+		}
+		testutil.CheckDeepEqual(t, 2, len(files))
+		testutil.CheckDeepEqual(t, files[0].Name(), "bam.link")
+		testutil.CheckDeepEqual(t, files[1].Name(), "bam.txt")
+		// TODO fix this
+		// path := filepath.Join(testDir, "output/another", "bam.link")
+		//linkName, err := os.Readlink(path)
+		//if err != nil {
+		//	t.Fatal(err)
+		//}
+		//testutil.CheckDeepEqual(t, linkName, "bam.txt")
+	})
+
+}
+
+func setupMultistageTests(t *testing.T) (string, func()) {
+	testDir, err := ioutil.TempDir("", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Create workspace with files, dirs, and symlinks
+	// workspace tree:
+	// /root
+	//    /kaniko
+	//    /workspace
+	//     - /foo
+	//          - bam.txt
+	//          - bam.link -> bam.txt
+	//     - /bin
+	//          - exec.link -> ../exec
+	//      exec
+
+	// Make directory for stage or else the executor will create with permissions 0664
+	// and we will run into issue https://github.com/golang/go/issues/22323
+	if err := os.MkdirAll(filepath.Join(testDir, "kaniko/0"), 0755); err != nil {
+		t.Fatal(err)
+	}
+	workspace := filepath.Join(testDir, "workspace")
+	// Make foo
+	if err := os.MkdirAll(filepath.Join(workspace, "foo"), 0755); err != nil {
+		t.Fatal(err)
+	}
+	file := filepath.Join(workspace, "foo", "bam.txt")
+	if err := ioutil.WriteFile(file, []byte("meow"), 0755); err != nil {
+		t.Fatal(err)
+	}
+	os.Symlink("bam.txt", filepath.Join(workspace, "foo", "bam.link"))
+
+	// Make a file with contents link
+	file = filepath.Join(workspace, "exec")
+	if err := ioutil.WriteFile(file, []byte("woof"), 0755); err != nil {
+		t.Fatal(err)
+	}
+	// Make bin
+	if err := os.MkdirAll(filepath.Join(workspace, "bin"), 0755); err != nil {
+		t.Fatal(err)
+	}
+	os.Symlink("../exec", filepath.Join(workspace, "bin", "exec.link"))
+
+	// set up config
+	config.RootDir = testDir
+	config.KanikoDir = fmt.Sprintf("%s/%s", testDir, "kaniko")
+	// Write a whitelist path
+	if err := os.MkdirAll(filepath.Join(testDir, "proc"), 0755); err != nil {
+		t.Fatal(err)
+	}
+	mFile := filepath.Join(testDir, "proc/mountinfo")
+	mountInfo := fmt.Sprintf(
+		`36 35 98:0 /kaniko %s/kaniko rw,noatime master:1 - ext3 /dev/root rw,errors=continue
+36 35 98:0 /proc %s/proc rw,noatime master:1 - ext3 /dev/root rw,errors=continue
+`, testDir, testDir)
+	if err := ioutil.WriteFile(mFile, []byte(mountInfo), 0644); err != nil {
+		t.Fatal(err)
+	}
+	config.WhitelistPath = mFile
+	return testDir, func() {
+		config.KanikoDir = constants.KanikoDir
+		config.RootDir = constants.RootDir
+		config.WhitelistPath = constants.WhitelistPath
+	}
+}

pkg/filesystem/resolve.go

@@ -20,6 +20,7 @@ import (
 	"os"
 	"path/filepath"
 
+	"github.com/GoogleContainerTools/kaniko/pkg/config"
 	"github.com/GoogleContainerTools/kaniko/pkg/util"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
@@ -89,7 +90,6 @@ func ResolvePaths(paths []string, wl []util.WhitelistEntry) (pathsToAdd []string
 
 	// Also add parent directories to keep the permission of them correctly.
 	pathsToAdd = filesWithParentDirs(pathsToAdd)
-
 	return
 }
 
@@ -130,7 +130,7 @@ func resolveSymlinkAncestor(path string) (string, error) {
 	newPath := filepath.Clean(path)
 
 loop:
-	for newPath != "/" {
+	for newPath != config.RootDir {
 		fi, err := os.Lstat(newPath)
 		if err != nil {
 			return "", errors.Wrap(err, "resolvePaths: failed to lstat")

pkg/snapshot/snapshot.go

@@ -28,14 +28,14 @@ import (
 	"github.com/GoogleContainerTools/kaniko/pkg/timing"
 	"github.com/karrick/godirwalk"
 
-	"github.com/GoogleContainerTools/kaniko/pkg/constants"
+	"github.com/GoogleContainerTools/kaniko/pkg/config"
 
 	"github.com/GoogleContainerTools/kaniko/pkg/util"
 	"github.com/sirupsen/logrus"
 )
 
 // For testing
-var snapshotPathPrefix = constants.KanikoDir
+var snapshotPathPrefix = config.KanikoDir
 
 // Snapshotter holds the root directory from which to take snapshots, and a list of snapshots taken
 type Snapshotter struct {
@@ -63,7 +63,7 @@ func (s *Snapshotter) Key() (string, error) {
 // TakeSnapshot takes a snapshot of the specified files, avoiding directories in the whitelist, and creates
 // a tarball of the changed files. Return contents of the tarball, and whether or not any files were changed
 func (s *Snapshotter) TakeSnapshot(files []string) (string, error) {
-	f, err := ioutil.TempFile(snapshotPathPrefix, "")
+	f, err := ioutil.TempFile(config.KanikoDir, "")
 	if err != nil {
 		return "", err
 	}

pkg/util/command_util.go

@@ -26,13 +26,14 @@ import (
 	"strconv"
 	"strings"
 
-	"github.com/GoogleContainerTools/kaniko/pkg/constants"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/moby/buildkit/frontend/dockerfile/instructions"
 	"github.com/moby/buildkit/frontend/dockerfile/parser"
 	"github.com/moby/buildkit/frontend/dockerfile/shell"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
+
+	"github.com/GoogleContainerTools/kaniko/pkg/config"
 )
 
 // for testing
@@ -145,7 +146,7 @@ func matchSources(srcs, files []string) ([]string, error) {
 		src = filepath.Clean(src)
 		for _, file := range files {
 			if filepath.IsAbs(src) {
-				file = filepath.Join(constants.RootDir, file)
+				file = filepath.Join(config.RootDir, file)
 			}
 			matched, err := filepath.Match(src, file)
 			if err != nil {

pkg/util/fs_util.go

@@ -33,7 +33,7 @@ import (
 
 	otiai10Cpy "github.com/otiai10/copy"
 
-	"github.com/GoogleContainerTools/kaniko/pkg/constants"
+	"github.com/GoogleContainerTools/kaniko/pkg/config"
 	"github.com/docker/docker/builder/dockerignore"
 	"github.com/docker/docker/pkg/fileutils"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
@@ -51,7 +51,7 @@ type WhitelistEntry struct {
 
 var initialWhitelist = []WhitelistEntry{
 	{
-		Path:            "/kaniko",
+		Path:            config.KanikoDir,
 		PrefixMatchOnly: false,
 	},
 	{
@@ -125,7 +125,7 @@ func GetFSFromLayers(root string, layers []v1.Layer, opts ...FSOpt) ([]string, e
 		return nil, errors.New("must supply an extract function")
 	}
 
-	if err := DetectFilesystemWhitelist(constants.WhitelistPath); err != nil {
+	if err := DetectFilesystemWhitelist(config.WhitelistPath); err != nil {
 		return nil, err
 	}
 
@@ -188,7 +188,7 @@ func GetFSFromLayers(root string, layers []v1.Layer, opts ...FSOpt) ([]string, e
 // DeleteFilesystem deletes the extracted image file system
 func DeleteFilesystem() error {
 	logrus.Info("Deleting filesystem...")
-	return filepath.Walk(constants.RootDir, func(path string, info os.FileInfo, err error) error {
+	return filepath.Walk(config.RootDir, func(path string, info os.FileInfo, err error) error {
 		if err != nil {
 			// ignore errors when deleting.
 			return nil
@@ -209,7 +209,7 @@ func DeleteFilesystem() error {
 			logrus.Debugf("Not deleting %s, as it contains a whitelisted path", path)
 			return nil
 		}
-		if path == constants.RootDir {
+		if path == config.RootDir {
 			return nil
 		}
 		return os.RemoveAll(path)
@@ -388,7 +388,7 @@ func CheckWhitelist(path string) bool {
 }
 
 func checkWhitelistRoot(root string) bool {
-	if root == constants.RootDir {
+	if root == config.RootDir {
 		return false
 	}
 	return CheckWhitelist(root)
@@ -423,7 +423,7 @@ func DetectFilesystemWhitelist(path string) error {
 			}
 			continue
 		}
-		if lineArr[4] != constants.RootDir {
+		if lineArr[4] != config.RootDir {
 			logrus.Tracef("Appending %s from line: %s", lineArr[4], line)
 			whitelist = append(whitelist, WhitelistEntry{
 				Path:            lineArr[4],
@@ -463,16 +463,18 @@ func RelativeFiles(fp string, root string) ([]string, error) {
 // ParentDirectories returns a list of paths to all parent directories
 // Ex. /some/temp/dir -> [/, /some, /some/temp, /some/temp/dir]
 func ParentDirectories(path string) []string {
-	path = filepath.Clean(path)
+	dir := filepath.Clean(path)
-	dirs := strings.Split(path, "/")
+	var paths []string
-	dirPath := constants.RootDir
+	for {
-	paths := []string{constants.RootDir}
+		if dir == filepath.Clean(config.RootDir) || dir == "" || dir == "." {
-	for index, dir := range dirs {
+			break
-		if dir == "" || index == (len(dirs)-1) {
-			continue
 		}
-		dirPath = filepath.Join(dirPath, dir)
+		dir, _ = filepath.Split(dir)
-		paths = append(paths, dirPath)
+		dir = filepath.Clean(dir)
+		paths = append(paths, dir)
+	}
+	if len(paths) == 0 {
+		paths = append(paths, config.RootDir)
 	}
 	return paths
 }
@@ -484,7 +486,7 @@ func ParentDirectoriesWithoutLeadingSlash(path string) []string {
 	path = filepath.Clean(path)
 	dirs := strings.Split(path, "/")
 	dirPath := ""
-	paths := []string{constants.RootDir}
+	paths := []string{config.RootDir}
 	for index, dir := range dirs {
 		if dir == "" || index == (len(dirs)-1) {
 			continue
@@ -824,12 +826,13 @@ func getSymlink(path string) error {
 // For cross stage dependencies kaniko must persist the referenced path so that it can be used in
 // the dependent stage. For symlinks we copy the target path because copying the symlink would
 // result in a dead link
-func CopyFileOrSymlink(src string, destDir string) error {
+func CopyFileOrSymlink(src string, destDir string, root string) error {
 	destFile := filepath.Join(destDir, src)
+	src = filepath.Join(root, src)
 	if fi, _ := os.Lstat(src); IsSymlink(fi) {
 		link, err := os.Readlink(src)
 		if err != nil {
-			return err
+			return errors.Wrap(err, "copying file or symlink")
 		}
 		if err := createParentDirectory(destFile); err != nil {
 			return err

pkg/util/fs_util_test.go

@@ -30,6 +30,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/GoogleContainerTools/kaniko/pkg/config"
 	"github.com/GoogleContainerTools/kaniko/pkg/mocks/go-containerregistry/mockv1"
 	"github.com/GoogleContainerTools/kaniko/testutil"
 	"github.com/golang/mock/gomock"
@@ -157,11 +158,13 @@ func Test_ParentDirectories(t *testing.T) {
 	tests := []struct {
 		name     string
 		path     string
+		rootDir  string
 		expected []string
 	}{
 		{
-			name: "regular path",
+			name:    "regular path",
-			path: "/path/to/dir",
+			path:    "/path/to/dir",
+			rootDir: "/",
 			expected: []string{
 				"/",
 				"/path",
@@ -169,17 +172,50 @@ func Test_ParentDirectories(t *testing.T) {
 			},
 		},
 		{
-			name: "current directory",
+			name:    "current directory",
-			path: ".",
+			path:    ".",
+			rootDir: "/",
 			expected: []string{
 				"/",
 			},
 		},
+		{
+			name:    "non / root directory",
+			path:    "/tmp/kaniko/test/another/dir",
+			rootDir: "/tmp/kaniko/",
+			expected: []string{
+				"/tmp/kaniko",
+				"/tmp/kaniko/test",
+				"/tmp/kaniko/test/another",
+			},
+		},
+		{
+			name:    "non / root director same path",
+			path:    "/tmp/123",
+			rootDir: "/tmp/123",
+			expected: []string{
+				"/tmp/123",
+			},
+		},
+		{
+			name:    "non / root directory path",
+			path:    "/tmp/120162240/kaniko",
+			rootDir: "/tmp/120162240",
+			expected: []string{
+				"/tmp/120162240",
+			},
+		},
 	}
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
+			original := config.RootDir
+			defer func() { config.RootDir = original }()
+			config.RootDir = tt.rootDir
 			actual := ParentDirectories(tt.path)
+			sort.Strings(actual)
+			sort.Strings(tt.expected)
+
 			testutil.CheckErrorAndDeepEqual(t, false, nil, tt.expected, actual)
 		})
 	}

pkg/util/tar_util.go

@@ -28,6 +28,7 @@ import (
 	"strings"
 	"syscall"
 
+	"github.com/GoogleContainerTools/kaniko/pkg/config"
 	"github.com/docker/docker/pkg/archive"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
@@ -76,14 +77,14 @@ func (t *Tar) AddFileToTar(p string) error {
 		return err
 	}
 
-	if p != "/" {
+	if p == config.RootDir {
-		// Docker uses no leading / in the tarball
-		hdr.Name = strings.TrimLeft(p, "/")
-	} else {
 		// allow entry for / to preserve permission changes etc. (currently ignored anyway by Docker runtime)
-		hdr.Name = p
+		hdr.Name = "/"
+	} else {
+		// Docker uses no leading / in the tarball
+		hdr.Name = strings.TrimPrefix(p, config.RootDir)
+		hdr.Name = strings.TrimLeft(hdr.Name, "/")
 	}
-
 	// rootfs may not have been extracted when using cache, preventing uname/gname from resolving
 	// this makes this layer unnecessarily differ from a cached layer which does contain this information
 	hdr.Uname = ""