5 files changed, 55 insertions, 9 deletions
diff --git a/pkg/sentry/fs/dirent.go b/pkg/sentry/fs/dirent.go
index c0bc261a2..a0a35c242 100644
--- a/pkg/sentry/fs/dirent.go
+++ b/pkg/sentry/fs/dirent.go
@@ -805,7 +805,7 @@ func (d *Dirent) Bind(ctx context.Context, root *Dirent, name string, data trans
 	var childDir *Dirent
 	err := d.genericCreate(ctx, root, name, func() error {
 		var e error
-		childDir, e = d.Inode.Bind(ctx, name, data, perms)
+		childDir, e = d.Inode.Bind(ctx, d, name, data, perms)
 		if e != nil {
 			return e
 		}
diff --git a/pkg/sentry/fs/inode.go b/pkg/sentry/fs/inode.go
index aef1a1cb9..0b54c2e77 100644
--- a/pkg/sentry/fs/inode.go
+++ b/pkg/sentry/fs/inode.go
@@ -220,9 +220,9 @@ func (i *Inode) Rename(ctx context.Context, oldParent *Dirent, renamed *Dirent,
 }
 
 // Bind calls i.InodeOperations.Bind with i as the directory.
-func (i *Inode) Bind(ctx context.Context, name string, data transport.BoundEndpoint, perm FilePermissions) (*Dirent, error) {
+func (i *Inode) Bind(ctx context.Context, parent *Dirent, name string, data transport.BoundEndpoint, perm FilePermissions) (*Dirent, error) {
 	if i.overlay != nil {
-		return overlayBind(ctx, i.overlay, name, data, perm)
+		return overlayBind(ctx, i.overlay, parent, name, data, perm)
 	}
 	return i.InodeOperations.Bind(ctx, i, name, data, perm)
 }
diff --git a/pkg/sentry/fs/inode_overlay.go b/pkg/sentry/fs/inode_overlay.go
index cdffe173b..06506fb20 100644
--- a/pkg/sentry/fs/inode_overlay.go
+++ b/pkg/sentry/fs/inode_overlay.go
@@ -398,14 +398,14 @@ func overlayRename(ctx context.Context, o *overlayEntry, oldParent *Dirent, rena
 	return nil
 }
 
-func overlayBind(ctx context.Context, o *overlayEntry, name string, data transport.BoundEndpoint, perm FilePermissions) (*Dirent, error) {
+func overlayBind(ctx context.Context, o *overlayEntry, parent *Dirent, name string, data transport.BoundEndpoint, perm FilePermissions) (*Dirent, error) {
+	if err := copyUp(ctx, parent); err != nil {
+		return nil, err
+	}
+
 	o.copyMu.RLock()
 	defer o.copyMu.RUnlock()
-	// We do not support doing anything exciting with sockets unless there
-	// is already a directory in the upper filesystem.
-	if o.upper == nil {
-		return nil, syserror.EOPNOTSUPP
-	}
+
 	d, err := o.upper.InodeOperations.Bind(ctx, o.upper, name, data, perm)
 	if err != nil {
 		return nil, err
diff --git a/runsc/test/integration/BUILD b/runsc/test/integration/BUILD
index 0c4e4fa80..04ed885c6 100644
--- a/runsc/test/integration/BUILD
+++ b/runsc/test/integration/BUILD
@@ -8,6 +8,7 @@ go_test(
     srcs = [
         "exec_test.go",
         "integration_test.go",
+        "regression_test.go",
     ],
     embed = [":integration"],
     tags = [
diff --git a/runsc/test/integration/regression_test.go b/runsc/test/integration/regression_test.go
new file mode 100644
index 000000000..80bae9970
--- /dev/null
+++ b/runsc/test/integration/regression_test.go
@@ -0,0 +1,45 @@
+// Copyright 2019 The gVisor Authors.
+//
+// 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 integration
+
+import (
+	"strings"
+	"testing"
+
+	"gvisor.googlesource.com/gvisor/runsc/test/testutil"
+)
+
+// Test that UDS can be created using overlay when parent directory is in lower
+// layer only (b/134090485).
+//
+// Prerequisite: the directory where the socket file is created must not have
+// been open for write before bind(2) is called.
+func TestBindOverlay(t *testing.T) {
+	if err := testutil.Pull("ubuntu:trusty"); err != nil {
+		t.Fatal("docker pull failed:", err)
+	}
+	d := testutil.MakeDocker("bind-overlay-test")
+
+	cmd := "nc -l -U /var/run/sock& sleep 1 && echo foobar-asdf | nc -U /var/run/sock"
+	got, err := d.RunFg("ubuntu:trusty", "bash", "-c", cmd)
+	if err != nil {
+		t.Fatal("docker run failed:", err)
+	}
+
+	if want := "foobar-asdf"; !strings.Contains(got, want) {
+		t.Fatalf("docker run output is missing %q: %s", want, got)
+	}
+	defer d.CleanUp()
+}