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

 package graph

 import (

+	"errors"

 	"fmt"

 	"io"

 	"io/ioutil"

@@ -108,6 +109,7 @@ type downloadInfo struct {

 	layer   distribution.ReadSeekCloser

 	size    int64

 	err     chan error

+	out     io.Writer // Download progress is written here.

 }

 type errVerification struct{}

@@ -117,7 +119,7 @@ func (errVerification) Error() string { return "verification failed" }

 func (p *v2Puller) download(di *downloadInfo) {

 	logrus.Debugf("pulling blob %q to %s", di.digest, di.img.ID)

-	out := p.config.OutStream

+	out := di.out

 	if c, err := p.poolAdd("pull", "img:"+di.img.ID); err != nil {

 		if c != nil {

@@ -191,7 +193,7 @@ func (p *v2Puller) download(di *downloadInfo) {

 	di.err <- nil

 }

-func (p *v2Puller) pullV2Tag(tag, taggedName string) (bool, error) {

+func (p *v2Puller) pullV2Tag(tag, taggedName string) (verified bool, err error) {

 	logrus.Debugf("Pulling tag from V2 registry: %q", tag)

 	out := p.config.OutStream

@@ -204,7 +206,7 @@ func (p *v2Puller) pullV2Tag(tag, taggedName string) (bool, error) {

 	if err != nil {

 		return false, err

 	}

-	verified, err := p.validateManifest(manifest, tag)

+	verified, err = p.validateManifest(manifest, tag)

 	if err != nil {

 		return false, err

 	}

@@ -212,6 +214,27 @@ func (p *v2Puller) pullV2Tag(tag, taggedName string) (bool, error) {

 		logrus.Printf("Image manifest for %s has been verified", taggedName)

 	}

+	// By using a pipeWriter for each of the downloads to write their progress

+	// to, we can avoid an issue where this function returns an error but

+	// leaves behind running download goroutines. By splitting the writer

+	// with a pipe, we can close the pipe if there is any error, consequently

+	// causing each download to cancel due to an error writing to this pipe.

+	pipeReader, pipeWriter := io.Pipe()

+	go func() {

+		if _, err := io.Copy(out, pipeReader); err != nil {

+			logrus.Errorf("error copying from layer download progress reader: %s", err)

+		}

+	}()

+	defer func() {

+		if err != nil {

+			// All operations on the pipe are synchronous. This call will wait

+			// until all current readers/writers are done using the pipe then

+			// set the error. All successive reads/writes will return with this

+			// error.

+			pipeWriter.CloseWithError(errors.New("download canceled"))

+		}

+	}()

+

 	out.Write(p.sf.FormatStatus(tag, "Pulling from %s", p.repo.Name()))

 	downloads := make([]downloadInfo, len(manifest.FSLayers))

@@ -242,6 +265,7 @@ func (p *v2Puller) pullV2Tag(tag, taggedName string) (bool, error) {

 		out.Write(p.sf.FormatProgress(stringid.TruncateID(img.ID), "Pulling fs layer", nil))

 		downloads[i].err = make(chan error)

+		downloads[i].out = pipeWriter

 		go p.download(&downloads[i])

 	}

@@ -446,7 +446,7 @@ func (s *DockerRegistrySuite) TestPullFailsWithAlteredManifest(c *check.C) {

 	imageReference := fmt.Sprintf("%s@%s", repoName, manifestDigest)

 	out, exitStatus, _ := dockerCmdWithError("pull", imageReference)

 	if exitStatus == 0 {

-		c.Fatalf("expected a zero exit status but got %d: %s", exitStatus, out)

+		c.Fatalf("expected a non-zero exit status but got %d: %s", exitStatus, out)

 	}

 	expectedErrorMsg := fmt.Sprintf("image verification failed for digest %s", manifestDigest)