@@ -3,6 +3,8 @@ package graph

 import (

 	"bufio"

 	"compress/gzip"

+	"encoding/json"

+	"errors"

 	"fmt"

 	"io"

 	"io/ioutil"

@@ -199,6 +201,11 @@ func (p *v2Pusher) pushV2Tag(tag string) error {

 		p.layersPushed[dgst] = true

 	}

+	// Fix parent chain if necessary

+	if err = fixHistory(m); err != nil {

+		return err

+	}

+

 	logrus.Infof("Signed manifest for %s:%s using daemon's key: %s", p.repo.Name(), tag, p.trustKey.KeyID())

 	signed, err := manifest.Sign(m, p.trustKey)

 	if err != nil {

@@ -220,6 +227,90 @@ func (p *v2Pusher) pushV2Tag(tag string) error {

 	return manSvc.Put(signed)

 }

+// fixHistory makes sure that the manifest has parent IDs that are consistent

+// with its image IDs. Because local image IDs are generated from the

+// configuration and filesystem contents, but IDs in the manifest are preserved

+// from the original pull, it's possible to have inconsistencies where parent

+// IDs don't match up with the other IDs in the manifest. This happens in the

+// case where an engine pulls images where are identical except the IDs from the

+// manifest - the local ID will be the same, and one of the v1Compatibility

+// files gets discarded.

+func fixHistory(m *manifest.Manifest) error {

+	var lastID string

+

+	for i := len(m.History) - 1; i >= 0; i-- {

+		var historyEntry map[string]*json.RawMessage

+		if err := json.Unmarshal([]byte(m.History[i].V1Compatibility), &historyEntry); err != nil {

+			return err

+		}

+

+		idJSON, present := historyEntry["id"]

+		if !present || idJSON == nil {

+			return errors.New("missing id key in v1compatibility file")

+		}

+		var id string

+		if err := json.Unmarshal(*idJSON, &id); err != nil {

+			return err

+		}

+

+		parentJSON, present := historyEntry["parent"]

+

+		if i == len(m.History)-1 {

+			// The base layer must not reference a parent layer,

+			// otherwise the manifest is incomplete. There is an

+			// exception for Windows to handle base layers.

+			if present && parentJSON != nil {

+				var parent string

+				if err := json.Unmarshal(*parentJSON, &parent); err != nil {

+					return err

+				}

+				if parent != "" {

+					logrus.Debugf("parent id mismatch detected; fixing. parent reference: %s", parent)

+					delete(historyEntry, "parent")

+					fixedHistory, err := json.Marshal(historyEntry)

+					if err != nil {

+						return err

+					}

+					m.History[i].V1Compatibility = string(fixedHistory)

+				}

+			}

+		} else {

+			// For all other layers, the parent ID should equal the

+			// ID of the next item in the history list. If it

+			// doesn't, fix it up (but preserve all other fields,

+			// possibly including fields that aren't known to this

+			// engine version).

+			if !present || parentJSON == nil {

+				return errors.New("missing parent key in v1compatibility file")

+			}

+			var parent string

+			if err := json.Unmarshal(*parentJSON, &parent); err != nil {

+				return err

+			}

+			if parent != lastID {

+				logrus.Debugf("parent id mismatch detected; fixing. parent reference: %s actual id: %s", parent, id)

+				historyEntry["parent"] = rawJSON(lastID)

+				fixedHistory, err := json.Marshal(historyEntry)

+				if err != nil {

+					return err

+				}

+				m.History[i].V1Compatibility = string(fixedHistory)

+			}

+		}

+		lastID = id

+	}

+

+	return nil

+}

+

+func rawJSON(value interface{}) *json.RawMessage {

+	jsonval, err := json.Marshal(value)

+	if err != nil {

+		return nil

+	}

+	return (*json.RawMessage)(&jsonval)

+}

+

 func (p *v2Pusher) pushV2Image(bs distribution.BlobService, img *image.Image) (digest.Digest, error) {

 	out := p.config.OutStream

@@ -2,13 +2,16 @@ package main

 import (

 	"archive/tar"

+	"encoding/json"

 	"fmt"

 	"io/ioutil"

 	"os"

 	"os/exec"

+	"path/filepath"

 	"strings"

 	"time"

+	"github.com/docker/docker/image"

 	"github.com/go-check/check"

 )

@@ -97,6 +100,46 @@ func (s *DockerRegistrySuite) TestPushMultipleTags(c *check.C) {

 	}

 }

+// TestPushBadParentChain tries to push an image with a corrupted parent chain

+// in the v1compatibility files, and makes sure the push process fixes it.

+func (s *DockerRegistrySuite) TestPushBadParentChain(c *check.C) {

+	repoName := fmt.Sprintf("%v/dockercli/badparent", privateRegistryURL)

+

+	id, err := buildImage(repoName, `

+	    FROM busybox

+	    CMD echo "adding another layer"

+	    `, true)

+	if err != nil {

+		c.Fatal(err)

+	}

+

+	// Push to create v1compatibility file

+	dockerCmd(c, "push", repoName)

+

+	// Corrupt the parent in the v1compatibility file from the top layer

+	filename := filepath.Join(dockerBasePath, "graph", id, "v1Compatibility")

+

+	jsonBytes, err := ioutil.ReadFile(filename)

+	c.Assert(err, check.IsNil, check.Commentf("Could not read v1Compatibility file: %s", err))

+

+	var img image.Image

+	err = json.Unmarshal(jsonBytes, &img)

+	c.Assert(err, check.IsNil, check.Commentf("Could not unmarshal json: %s", err))

+

+	img.Parent = "1234123412341234123412341234123412341234123412341234123412341234"

+

+	jsonBytes, err = json.Marshal(&img)

+	c.Assert(err, check.IsNil, check.Commentf("Could not marshal json: %s", err))

+

+	err = ioutil.WriteFile(filename, jsonBytes, 0600)

+	c.Assert(err, check.IsNil, check.Commentf("Could not write v1Compatibility file: %s", err))

+

+	dockerCmd(c, "push", repoName)

+

+	// pull should succeed

+	dockerCmd(c, "pull", repoName)

+}

+

 func (s *DockerRegistrySuite) TestPushEmptyLayer(c *check.C) {

 	repoName := fmt.Sprintf("%v/dockercli/emptylayer", privateRegistryURL)

 	emptyTarball, err := ioutil.TempFile("", "empty_tarball")