From ac5d363e67e01c769b4d9e20ed76a278434ee4de Mon Sep 17 00:00:00 2001
From: Derek McGowan <derek@mcgstyle.net>
Date: Tue, 19 Jun 2018 15:56:41 -0700
Subject: [PATCH] Update overlay2 to use naive diff for changes

The archive changes function is not implemented correctly
to handle opaque directories.

Signed-off-by: Derek McGowan <derek@mcgstyle.net>
---
 daemon/graphdriver/overlay2/overlay.go      | 13 +---------
 daemon/graphdriver/overlay2/overlay_test.go |  2 +-
 pkg/archive/changes_linux.go                | 27 ---------------------
 3 files changed, 2 insertions(+), 40 deletions(-)

diff --git a/daemon/graphdriver/overlay2/overlay.go b/daemon/graphdriver/overlay2/overlay.go
index 5108a2c055..49b055cc03 100644
--- a/daemon/graphdriver/overlay2/overlay.go
+++ b/daemon/graphdriver/overlay2/overlay.go
@@ -754,16 +754,5 @@ func (d *Driver) Diff(id, parent string) (io.ReadCloser, error) {
 // Changes produces a list of changes between the specified layer and its
 // parent layer. If parent is "", then all changes will be ADD changes.
 func (d *Driver) Changes(id, parent string) ([]archive.Change, error) {
-	if useNaiveDiff(d.home) || !d.isParent(id, parent) {
-		return d.naiveDiff.Changes(id, parent)
-	}
-	// Overlay doesn't have snapshots, so we need to get changes from all parent
-	// layers.
-	diffPath := d.getDiffPath(id)
-	layers, err := d.getLowerDirs(id)
-	if err != nil {
-		return nil, err
-	}
-
-	return archive.OverlayChanges(layers, diffPath)
+	return d.naiveDiff.Changes(id, parent)
 }
diff --git a/daemon/graphdriver/overlay2/overlay_test.go b/daemon/graphdriver/overlay2/overlay_test.go
index 4a07137ed8..6befa7db57 100644
--- a/daemon/graphdriver/overlay2/overlay_test.go
+++ b/daemon/graphdriver/overlay2/overlay_test.go
@@ -62,7 +62,7 @@ func TestOverlayDiffApply10Files(t *testing.T) {
 }
 
 func TestOverlayChanges(t *testing.T) {
-	skipIfNaive(t)
+	t.Skipf("Cannot run test with naive change algorithm")
 	graphtest.DriverTestChanges(t, driverName)
 }
 
diff --git a/pkg/archive/changes_linux.go b/pkg/archive/changes_linux.go
index 78a5393c8e..f8792b3d4e 100644
--- a/pkg/archive/changes_linux.go
+++ b/pkg/archive/changes_linux.go
@@ -284,30 +284,3 @@ func clen(n []byte) int {
 	}
 	return len(n)
 }
-
-// OverlayChanges walks the path rw and determines changes for the files in the path,
-// with respect to the parent layers
-func OverlayChanges(layers []string, rw string) ([]Change, error) {
-	return changes(layers, rw, overlayDeletedFile, nil)
-}
-
-func overlayDeletedFile(root, path string, fi os.FileInfo) (string, error) {
-	if fi.Mode()&os.ModeCharDevice != 0 {
-		s := fi.Sys().(*syscall.Stat_t)
-		if unix.Major(uint64(s.Rdev)) == 0 && unix.Minor(uint64(s.Rdev)) == 0 { // nolint: unconvert
-			return path, nil
-		}
-	}
-	if fi.Mode()&os.ModeDir != 0 {
-		opaque, err := system.Lgetxattr(filepath.Join(root, path), "trusted.overlay.opaque")
-		if err != nil {
-			return "", err
-		}
-		if len(opaque) == 1 && opaque[0] == 'y' {
-			return path, nil
-		}
-	}
-
-	return "", nil
-
-}