@@ -31,7 +31,6 @@ import (

 	"github.com/docker/docker/pkg/parsers"

 	"github.com/docker/docker/pkg/progressreader"

 	"github.com/docker/docker/pkg/streamformatter"

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

 	"github.com/docker/docker/pkg/ulimit"

 	"github.com/docker/docker/pkg/units"

 	"github.com/docker/docker/pkg/urlutil"

@@ -340,15 +339,15 @@ func getDockerfileRelPath(givenContextDir, givenDockerfile string) (absContextDi

 		absDockerfile = filepath.Join(absContextDir, absDockerfile)

 	}

-	// Verify that 'filename' is within the build context

-	absDockerfile, err = symlink.FollowSymlinkInScope(absDockerfile, absContextDir)

+	// Evaluate symlinks in the path to the Dockerfile too.

+	absDockerfile, err = filepath.EvalSymlinks(absDockerfile)

 	if err != nil {

-		return "", "", fmt.Errorf("The Dockerfile (%s) must be within the build context (%s)", givenDockerfile, givenContextDir)

+		return "", "", fmt.Errorf("unable to evaluate symlinks in Dockerfile path: %v", err)

 	}

 	if _, err := os.Lstat(absDockerfile); err != nil {

 		if os.IsNotExist(err) {

-			return "", "", fmt.Errorf("Cannot locate Dockerfile: absDockerfile: %q", absDockerfile)

+			return "", "", fmt.Errorf("Cannot locate Dockerfile: %q", absDockerfile)

 		}

 		return "", "", fmt.Errorf("unable to stat Dockerfile: %v", err)

 	}

@@ -357,6 +356,10 @@ func getDockerfileRelPath(givenContextDir, givenDockerfile string) (absContextDi

 		return "", "", fmt.Errorf("unable to get relative Dockerfile path: %v", err)

 	}

+	if strings.HasPrefix(relDockerfile, ".."+string(filepath.Separator)) {

+		return "", "", fmt.Errorf("The Dockerfile (%s) must be within the build context (%s)", givenDockerfile, givenContextDir)

+	}

+

 	return absContextDir, relDockerfile, nil

 }