mirror of
https://github.com/LadybirdBrowser/ladybird
synced 2026-05-12 01:46:46 +02:00
b9ec043b5a
Maintain a HashTable<HeapBlock*> of live heap blocks in the Heap, updated on block creation and destruction. Weak containers (WeakMap, WeakSet, WeakRef, FinalizationRegistry) now check block liveness before accessing cell memory in their remove_dead_cells() methods. This prevents use-after-free when blocks have been freed during incremental sweeping.
70 lines
2.0 KiB
C++
70 lines
2.0 KiB
C++
/*
|
|
* Copyright (c) 2021, Idan Horowitz <idan.horowitz@serenityos.org>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
#include <LibGC/HeapBlock.h>
|
|
#include <LibJS/Runtime/ExternalMemory.h>
|
|
#include <LibJS/Runtime/WeakSet.h>
|
|
|
|
namespace JS {
|
|
|
|
GC_DEFINE_ALLOCATOR(WeakSet);
|
|
|
|
GC::Ref<WeakSet> WeakSet::create(Realm& realm)
|
|
{
|
|
return realm.create<WeakSet>(realm.intrinsics().weak_set_prototype());
|
|
}
|
|
|
|
WeakSet::WeakSet(Object& prototype)
|
|
: Object(ConstructWithPrototypeTag::Tag, prototype)
|
|
, WeakContainer(heap())
|
|
{
|
|
}
|
|
|
|
bool WeakSet::weak_set_has(GC::Ptr<Cell> value) const
|
|
{
|
|
return m_values.contains(value);
|
|
}
|
|
|
|
void WeakSet::weak_set_add(GC::Ptr<Cell> value)
|
|
{
|
|
auto old_external_memory_size = external_memory_size();
|
|
m_values.set(value, AK::HashSetExistingEntryBehavior::Keep);
|
|
account_external_memory_change(old_external_memory_size);
|
|
}
|
|
|
|
bool WeakSet::weak_set_remove(GC::Ptr<Cell> value)
|
|
{
|
|
auto old_external_memory_size = external_memory_size();
|
|
auto did_remove = m_values.remove(value);
|
|
if (did_remove)
|
|
account_external_memory_change(old_external_memory_size);
|
|
return did_remove;
|
|
}
|
|
|
|
void WeakSet::remove_dead_cells(Badge<GC::Heap>)
|
|
{
|
|
m_values.remove_all_matching([this](Cell* cell) {
|
|
auto* block = GC::HeapBlock::from_cell(cell);
|
|
return !heap().is_live_heap_block(block) || cell->state() != Cell::State::Live || !cell->is_marked();
|
|
});
|
|
}
|
|
|
|
size_t WeakSet::external_memory_size() const
|
|
{
|
|
return saturating_add_external_memory_size(Object::external_memory_size(), hash_table_external_memory_size(m_values));
|
|
}
|
|
|
|
void WeakSet::account_external_memory_change(size_t old_external_memory_size)
|
|
{
|
|
auto new_external_memory_size = external_memory_size();
|
|
if (new_external_memory_size > old_external_memory_size)
|
|
heap().did_allocate_external_memory(new_external_memory_size - old_external_memory_size);
|
|
else if (old_external_memory_size > new_external_memory_size)
|
|
heap().did_free_external_memory(old_external_memory_size - new_external_memory_size);
|
|
}
|
|
|
|
}
|