From a4877338826381d454dfdae74242a007b3aac9e0 Mon Sep 17 00:00:00 2001
From: Ulf Hermann <ulf.hermann@digia.com>
Date: Thu, 6 Nov 2014 14:40:37 +0100
Subject: [PATCH] Avoid stack overflow when destroying InternalClass
If there are deep object hierarchies connected to an InternalClass the
recursive nature of the destroy() method could lead to a stack
overflow. By changing the recursion into an iteration this is avoided.
Change-Id: I6667f268a366749c2dbc5f7147882388f192a9c5
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>
---
src/qml/jsruntime/qv4internalclass.cpp | 35 +++++++++++++-------------
1 file changed, 17 insertions(+), 18 deletions(-)
diff --git a/src/qml/jsruntime/qv4internalclass.cpp b/src/qml/jsruntime/qv4internalclass.cpp
index a59c3892a1..bb22e30ac1 100644
--- a/src/qml/jsruntime/qv4internalclass.cpp
+++ b/src/qml/jsruntime/qv4internalclass.cpp
@@ -412,25 +412,24 @@ InternalClass *InternalClass::frozen()
void InternalClass::destroy()
{
- if (!engine)
- return;
- engine = 0;
-
- propertyTable.~PropertyHash();
- nameMap.~SharedInternalClassData<String *>();
- propertyData.~SharedInternalClassData<PropertyAttributes>();
+ QList<InternalClass *> destroyStack;
+ destroyStack.append(this);
- if (m_sealed)
- m_sealed->destroy();
-
- if (m_frozen)
- m_frozen->destroy();
-
- for (QHash<Transition, InternalClass *>::ConstIterator it = transitions.begin(), end = transitions.end();
- it != end; ++it)
- it.value()->destroy();
-
- transitions.clear();
+ while (!destroyStack.isEmpty()) {
+ InternalClass *next = destroyStack.takeLast();
+ if (!next->engine)
+ continue;
+ next->engine = 0;
+ next->propertyTable.~PropertyHash();
+ next->nameMap.~SharedInternalClassData<String *>();
+ next->propertyData.~SharedInternalClassData<PropertyAttributes>();
+ if (next->m_sealed)
+ destroyStack.append(next->m_sealed);
+ if (next->m_frozen)
+ destroyStack.append(next->m_frozen);
+ destroyStack.append(next->transitions.values());
+ next->transitions.clear();
+ }
}
struct InternalClassPoolVisitor
--
GitLab