[mono] Prevent direct MonoClass field access

Fixes mono/mono#15544

### After adding configure flag
<img width="874" alt="Screen Shot 2020-01-30 at 10 54 25 AM" src="https://user-images.githubusercontent.com/16830051/73466184-81f4c180-434f-11ea-87f0-0863c32b1251.png">

### After using m_class accessors
<img width="865" alt="Screen Shot 2020-01-30 at 10 55 04 AM" src="https://user-images.githubusercontent.com/16830051/73466229-93d66480-434f-11ea-8914-cef5571a0528.png">

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diff --git a/src/mono/mono/mini/mini-wasm-debugger.c b/src/mono/mono/mini/mini-wasm-debugger.c
index 7dffb14ad8ab5e3cc6cb0c918dca4d5256b43235..4eb3a27bd53a468694286d63056553f8c4545392 100644 (file)
--- a/src/mono/mono/mini/mini-wasm-debugger.c
+++ b/src/mono/mono/mini/mini-wasm-debugger.c
@@ -655,11 +655,11 @@ static gboolean describe_value(MonoType * type, gpointer addr)
                        } else {
                                GString *class_name;
                                class_name = g_string_new ("");
-                               if (*(obj->vtable->klass->name_space)) {
-                                       g_string_append (class_name, obj->vtable->klass->name_space);
+                               if (*(m_class_get_name_space (obj->vtable->klass))) {
+                                       g_string_append (class_name, m_class_get_name_space (obj->vtable->klass));
                                        g_string_append_c (class_name, '.');
                                }
-                               g_string_append (class_name, obj->vtable->klass->name);
+                               g_string_append (class_name, m_class_get_name (obj->vtable->klass));
                                if (m_class_get_byval_arg (obj->vtable->klass)->type == MONO_TYPE_SZARRAY || m_class_get_byval_arg (obj->vtable->klass)->type == MONO_TYPE_ARRAY)
                                        mono_wasm_add_array_var (class_name->str, get_object_id(obj));
                                else
@@ -821,11 +821,11 @@ describe_this (MonoStackFrameInfo *info, MonoContext *ctx, gpointer ud)
                mono_wasm_add_properties_var("this");
                GString *class_name;
                class_name = g_string_new ("");
-               if (*(obj->vtable->klass->name_space)) {
-                       g_string_append (class_name, obj->vtable->klass->name_space);
+               if (*(m_class_get_name_space (obj->vtable->klass))) {
+                       g_string_append (class_name, m_class_get_name_space (obj->vtable->klass));
                        g_string_append_c (class_name, '.');
                }
-               g_string_append (class_name, obj->vtable->klass->name);
+               g_string_append (class_name, m_class_get_name (obj->vtable->klass));
                mono_wasm_add_obj_var (class_name->str, get_object_id(obj));
                g_string_free(class_name, FALSE);
        }