LibDeviceTree: Fix stale pointers in phandle and parent handling

We need to set them after we've created the full tree, as otherwise the
HashMap containing the nodes may reallocate and invalidate the pointers.

Userland/Libraries/LibDeviceTree/DeviceTree.cpp

@@ -39,14 +39,7 @@ ErrorOr<NonnullOwnPtr<DeviceTree>> DeviceTree::parse(ReadonlyBytes flattened_dev
                 current_node = current_node->parent();
                 return IterationDecision::Continue;
             },
-            .on_property = [&device_tree, &current_node](StringView name, ReadonlyBytes value) -> ErrorOr<IterationDecision> {
-                DeviceTreeProperty property { value };
-
-                if (name == "phandle"sv) {
-                    auto phandle = property.as<u32>();
-                    TRY(device_tree->set_phandle(phandle, current_node));
-                }
-
+            .on_property = [&current_node](StringView name, ReadonlyBytes value) -> ErrorOr<IterationDecision> {
                 TRY(current_node->properties().try_set(name, DeviceTreeProperty { value }));
                 return IterationDecision::Continue;
             },
@@ -58,6 +51,25 @@ ErrorOr<NonnullOwnPtr<DeviceTree>> DeviceTree::parse(ReadonlyBytes flattened_dev
             },
         }));
 
+    // FIXME: While growing the a nodes children map, we might have reallocated it's storage
+    //        breaking the parent pointers of the children, so we need to fix them here
+    auto fix_parent = [](auto self, DeviceTreeNodeView& node) -> void {
+        for (auto& [name, child] : node.children()) {
+            child.m_parent = &node;
+            self(self, child);
+        }
+    };
+
+    fix_parent(fix_parent, *device_tree);
+    // Note: For the same reason as above, we need to postpone setting the phandles until the tree is fully built
+    TRY(device_tree->for_each_node([&device_tree]([[maybe_unused]] StringView name, DeviceTreeNodeView& node) -> ErrorOr<RecursionDecision> {
+        if (auto phandle = node.get_property("phandle"sv); phandle.has_value()) {
+            auto phandle_value = phandle.value().as<u32>();
+            TRY(device_tree->set_phandle(phandle_value, &node));
+        }
+        return RecursionDecision::Recurse;
+    }));
+
     return device_tree;
 }