3 files changed, 26 insertions, 21 deletions
diff --git a/pkg/sentry/contexttest/contexttest.go b/pkg/sentry/contexttest/contexttest.go
index 8e5658c7a..dfd195a23 100644
--- a/pkg/sentry/contexttest/contexttest.go
+++ b/pkg/sentry/contexttest/contexttest.go
@@ -144,27 +144,7 @@ func (t *TestContext) MemoryFile() *pgalloc.MemoryFile {
 // RootContext returns a Context that may be used in tests that need root
 // credentials. Uses ptrace as the platform.Platform.
 func RootContext(tb testing.TB) context.Context {
-	return WithCreds(Context(tb), auth.NewRootCredentials(auth.NewRootUserNamespace()))
-}
-
-// WithCreds returns a copy of ctx carrying creds.
-func WithCreds(ctx context.Context, creds *auth.Credentials) context.Context {
-	return &authContext{ctx, creds}
-}
-
-type authContext struct {
-	context.Context
-	creds *auth.Credentials
-}
-
-// Value implements context.Context.
-func (ac *authContext) Value(key interface{}) interface{} {
-	switch key {
-	case auth.CtxCredentials:
-		return ac.creds
-	default:
-		return ac.Context.Value(key)
-	}
+	return auth.ContextWithCredentials(Context(tb), auth.NewRootCredentials(auth.NewRootUserNamespace()))
 }
 
 // WithLimitSet returns a copy of ctx carrying l.
diff --git a/pkg/sentry/fsimpl/overlay/copy_up.go b/pkg/sentry/fsimpl/overlay/copy_up.go
index b3d19ff82..13735eb05 100644
--- a/pkg/sentry/fsimpl/overlay/copy_up.go
+++ b/pkg/sentry/fsimpl/overlay/copy_up.go
@@ -22,6 +22,7 @@ import (
 	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/fspath"
+	"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
 	"gvisor.dev/gvisor/pkg/sentry/vfs"
 	"gvisor.dev/gvisor/pkg/syserror"
 	"gvisor.dev/gvisor/pkg/usermem"
@@ -40,6 +41,10 @@ func (d *dentry) copyUpLocked(ctx context.Context) error {
 		return nil
 	}
 
+	// Attach our credentials to the context, as some VFS operations use
+	// credentials from context rather an take an explicit creds parameter.
+	ctx = auth.ContextWithCredentials(ctx, d.fs.creds)
+
 	ftype := atomic.LoadUint32(&d.mode) & linux.S_IFMT
 	switch ftype {
 	case linux.S_IFREG, linux.S_IFDIR, linux.S_IFLNK, linux.S_IFBLK, linux.S_IFCHR:
diff --git a/pkg/sentry/kernel/auth/context.go b/pkg/sentry/kernel/auth/context.go
index ef5723127..c08d47787 100644
--- a/pkg/sentry/kernel/auth/context.go
+++ b/pkg/sentry/kernel/auth/context.go
@@ -34,3 +34,23 @@ func CredentialsFromContext(ctx context.Context) *Credentials {
 	}
 	return NewAnonymousCredentials()
 }
+
+// ContextWithCredentials returns a copy of ctx carrying creds.
+func ContextWithCredentials(ctx context.Context, creds *Credentials) context.Context {
+	return &authContext{ctx, creds}
+}
+
+type authContext struct {
+	context.Context
+	creds *Credentials
+}
+
+// Value implements context.Context.
+func (ac *authContext) Value(key interface{}) interface{} {
+	switch key {
+	case CtxCredentials:
+		return ac.creds
+	default:
+		return ac.Context.Value(key)
+	}
+}