fix(html): deserialize clones in receiver realm

moli-renderer-v8/src/context_bootstrap/shared/clone.rs

@@ -301,8 +301,17 @@ pub(crate) fn structured_clone_value_with_options<'s>(
     value: v8::Local<'s, v8::Value>,
     options: v8::Local<'s, v8::Value>,
 ) -> Option<v8::Local<'s, v8::Value>> {
+    let payload = structured_serialize_value_with_options(scope, value, options)?;
+    structured_deserialize_value(scope, &payload)
+}
+
+pub(crate) fn structured_serialize_value_with_options<'s>(
+    scope: &mut v8::PinScope<'s, '_>,
+    value: v8::Local<'s, v8::Value>,
+    options: v8::Local<'s, v8::Value>,
+) -> Option<V8StructuredClonePayload> {
     let transfers = parse_structured_clone_options_transfer_list(scope, options)?;
-    let payload = serialize_for_wire_for_runtime_with_transfers(
+    serialize_for_wire_for_runtime_with_transfers(
         scope,
         value,
         &transfers.array_buffers,
@@ -310,8 +319,7 @@ pub(crate) fn structured_clone_value_with_options<'s>(
         &transfers.readable_streams,
         &transfers.writable_streams,
         &transfers.transform_streams,
-    )?;
-    structured_deserialize_value(scope, &payload)
+    )
 }
 
 pub(crate) fn structured_clone_value_for_storage<'s>(

moli-renderer-v8/src/context_bootstrap/window_runtime/structured_clone.rs

@@ -5,9 +5,59 @@ pub(in crate::context_bootstrap) fn window_structured_clone_callback<'s>(
     args: v8::FunctionCallbackArguments<'s>,
     mut rv: v8::ReturnValue<'_, v8::Value>,
 ) {
-    if let Some(value) = structured_clone_value_with_options(scope, args.get(0), args.get(1)) {
-        rv.set(value);
-    } else {
+    let Some(host_ptr) = context_host_ptr_from_global_bridge(scope) else {
         rv.set_undefined();
+        return;
+    };
+    let receiver = match crate::native_bridge::WindowOperationReceiver::capture_and_authorize(
+        scope,
+        args.this(),
+        unsafe { &*host_ptr },
+    ) {
+        Ok(receiver) => receiver,
+        Err(crate::native_bridge::WindowOperationReceiverCaptureError::IllegalInvocation) => {
+            throw_type_error(scope, "Illegal invocation");
+            return;
+        }
+        Err(crate::native_bridge::WindowOperationReceiverCaptureError::CrossOrigin) => {
+            crate::native_bridge::throw_cross_origin_location_security_error(scope);
+            return;
+        }
+    };
+
+    if args.length() < 1 {
+        throw_type_error(
+            scope,
+            &crate::webidl::WebIdlError::missing_required(crate::webidl::Context::argument(
+                "Window.structuredClone",
+                1,
+            ))
+            .to_string(),
+        );
+        return;
     }
+
+    // Web IDL converts `options`, and structured serialization can invoke
+    // author getters, while the operation function's Realm is still current.
+    // Only deserialization uses `this`'s relevant Realm.
+    let Some(payload) = structured_serialize_value_with_options(scope, args.get(0), args.get(1))
+    else {
+        rv.set_undefined();
+        return;
+    };
+    let Some(binding) = receiver.resolve_live_binding(unsafe { &*host_ptr }) else {
+        // Chromium returns undefined when the receiver's Window has already
+        // been discarded; more importantly, no retired V8 context is entered.
+        rv.set_undefined();
+        return;
+    };
+    let cloned = binding.with_current_scope(scope, host_ptr, |scope, _dispatch_scope| {
+        structured_deserialize_value(scope, &payload).map(|value| v8::Global::new(scope, value))
+    });
+    let Some(Some(cloned)) = cloned else {
+        rv.set_undefined();
+        return;
+    };
+    let cloned = v8::Local::new(scope, cloned);
+    rv.set(cloned);
 }

moli-renderer-v8/src/script_vm/tests/browser_api/structured_clone.rs

@@ -1,5 +1,82 @@
 use super::*;
 
+#[test]
+fn structured_clone_deserializes_in_the_receiver_realm() {
+    let mut vm = new_storage_test_vm("https://structured-clone-receiver-realm.test/");
+
+    vm.eval(
+        r#"
+        (() => {
+          const frame = document.createElement("iframe");
+          (document.body || document.documentElement || document).appendChild(frame);
+          globalThis.__structuredCloneRealmFrame = frame;
+          return "ready";
+        })()
+        "#,
+    )
+    .expect("structuredClone receiver Realm setup should evaluate");
+    vm.drain_pending_child_frame_work_for_test();
+
+    let result = vm
+        .eval(
+            r#"
+            (() => {
+              const frame = globalThis.__structuredCloneRealmFrame;
+              const child = frame.contentWindow;
+              const constructors = ["Object", "Array", "Date", "RegExp"];
+              const intoTop = constructors.map(name => {
+                const clone = child.structuredClone.call(window, new child[name]);
+                return Object.getPrototypeOf(clone) === window[name].prototype;
+              });
+              const intoChild = constructors.map(name => {
+                const clone = window.structuredClone.call(child, new window[name]);
+                return Object.getPrototypeOf(clone) === child[name].prototype;
+              });
+
+              const buffer = new child.ArrayBuffer(8);
+              const transferred = child.structuredClone.call(window, buffer, {
+                transfer: [buffer]
+              });
+
+              const exceptionRealm = callback => {
+                try {
+                  callback();
+                  return "missing";
+                } catch (error) {
+                  return error instanceof child.TypeError ? "child" : "other";
+                }
+              };
+              const illegalInvocation = exceptionRealm(() =>
+                child.structuredClone.call({}, 1));
+              const missingArgument = exceptionRealm(() =>
+                child.structuredClone.call(window));
+
+              frame.remove();
+              const detached = child.structuredClone("detached") === undefined;
+
+              return JSON.stringify({
+                intoTop,
+                intoChild,
+                transfer: [
+                  buffer.byteLength,
+                  transferred.byteLength,
+                  transferred instanceof window.ArrayBuffer
+                ],
+                illegalInvocation,
+                missingArgument,
+                detached
+              });
+            })()
+            "#,
+        )
+        .expect("cross-Realm structuredClone probe should evaluate");
+
+    assert_eq!(
+        result,
+        r#"{"intoTop":[true,true,true,true],"intoChild":[true,true,true,true],"transfer":[0,8,true],"illegalInvocation":"child","missingArgument":"child","detached":true}"#,
+    );
+}
+
 #[test]
 fn structured_clone_preserves_webassembly_module() {
     let mut vm = new_storage_test_vm("https://example.com/wasm-clone");