Fix use-after-free

Fixes #443
laverdet · Jan 17, 2024 · db24a06 · db24a06
1 parent 90a4746
commit db24a06
Show file tree

Hide file tree

Showing 3 changed files with 10 additions and 3 deletions.
diff --git a/src/external_copy/string.cc b/src/external_copy/string.cc
@@ -20,7 +20,8 @@ class ExternalString final : public v8::String::ExternalStringResource {
 		ExternalString(const ExternalString&) = delete;
 
 		~ExternalString() final {
-			IsolateEnvironment::GetCurrent()->AdjustExtraAllocatedMemory(-static_cast<int>(this->value->size()));
+			if (auto *env = IsolateEnvironment::GetCurrent())
+				env->AdjustExtraAllocatedMemory(-static_cast<int>(this->value->size()));
 		}
 
 		auto operator= (const ExternalString&) = delete;
@@ -46,7 +47,8 @@ class ExternalStringOneByte final : public v8::String::ExternalOneByteStringReso
 		ExternalStringOneByte(const ExternalStringOneByte&) = delete;
 
 		~ExternalStringOneByte() final {
-			IsolateEnvironment::GetCurrent()->AdjustExtraAllocatedMemory(-static_cast<int>(this->value->size()));
+			if (auto *env = IsolateEnvironment::GetCurrent())
+				env->AdjustExtraAllocatedMemory(-static_cast<int>(this->value->size()));
 		}
 
 		auto operator= (const ExternalStringOneByte&) = delete;

diff --git a/src/isolate/executor.cc b/src/isolate/executor.cc
@@ -17,6 +17,11 @@ Executor::Executor(IsolateEnvironment& env) :
 	default_executor{*(current_executor == nullptr ? (current_executor = this) : &current_executor->default_executor)},
 	default_thread{&default_executor == this ? std::this_thread::get_id() : default_executor.default_thread} {}
 
+Executor::~Executor() {
+	if (current_executor == this)
+		current_executor = nullptr;
+}
+
 auto Executor::MayRunInlineTasks(IsolateEnvironment& env) -> bool {
 	if (current_executor == &env.executor) {
 		if (env.nodejs_isolate) {

diff --git a/src/isolate/executor.h b/src/isolate/executor.h
@@ -21,7 +21,7 @@ class Executor { // "En taro adun"
 	public:
 		explicit Executor(IsolateEnvironment& env);
 		Executor(const Executor&) = delete;
-		~Executor() = default;
+		~Executor();
 		auto operator= (const Executor&) = delete;
 
 		static auto GetCurrentEnvironment() -> IsolateEnvironment*;