3 files changed, 25 insertions, 0 deletions
diff --git a/pkg/sentry/kernel/auth/BUILD b/pkg/sentry/kernel/auth/BUILD
index 2bc49483a..869e49ebc 100644
--- a/pkg/sentry/kernel/auth/BUILD
+++ b/pkg/sentry/kernel/auth/BUILD
@@ -57,6 +57,7 @@ go_library(
         "id_map_set.go",
         "user_namespace.go",
     ],
+    marshal = True,
     visibility = ["//pkg/sentry:internal"],
     deps = [
         "//pkg/abi/linux",
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)
+	}
+}
diff --git a/pkg/sentry/kernel/auth/id.go b/pkg/sentry/kernel/auth/id.go
index 0a58ba17c..4c32ee703 100644
--- a/pkg/sentry/kernel/auth/id.go
+++ b/pkg/sentry/kernel/auth/id.go
@@ -19,9 +19,13 @@ import (
 )
 
 // UID is a user ID in an unspecified user namespace.
+//
+// +marshal
 type UID uint32
 
 // GID is a group ID in an unspecified user namespace.
+//
+// +marshal slice:GIDSlice
 type GID uint32
 
 // In the root user namespace, user/group IDs have a 1-to-1 relationship with