Bug 898906. Fix this bug by making nsMimeType objects hold their active plugin alive, and rely on the cycle collector to break the explicit reference cycle. r=mccr8

---
 dom/base/crashtests/898906.html     | 14 ++++++++++++++
 dom/base/crashtests/crashtests.list |  3 ++-
 dom/base/nsMimeTypeArray.cpp        |  2 +-
 dom/base/nsMimeTypeArray.h          | 14 ++++++--------
 dom/base/nsPluginArray.cpp          | 24 +-----------------------
 dom/base/nsPluginArray.h            |  2 --
 6 files changed, 24 insertions(+), 35 deletions(-)
 create mode 100644 dom/base/crashtests/898906.html
This commit is contained in:
Johnny Stenback 2013-07-30 17:46:46 -07:00
parent 30db6e7534
commit e8b8439a32
6 changed files with 24 additions and 35 deletions

View File

@ -0,0 +1,14 @@
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<script>
var plug = navigator.plugins[0];
var mime = plug[0];
// This shouldn't leak.
mime.expando = true;
</script>
</head>
</html>

View File

@ -40,4 +40,5 @@ load 706283-1.html
load 708405-1.html
load 745495.html
load 844559.html
load 886213.html
load 886213.html
load 898906.html

View File

@ -219,7 +219,7 @@ nsMimeTypeArray::EnsureMimeTypes()
NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(nsMimeType, AddRef)
NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(nsMimeType, Release)
NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_0(nsMimeType)
NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_1(nsMimeType, mPluginElement)
nsMimeType::nsMimeType(nsWeakPtr aWindow, nsPluginElement* aPluginElement,
uint32_t aPluginTagMimeIndex, const nsAString& aType)

View File

@ -12,9 +12,9 @@
#include "nsTArray.h"
#include "nsWeakReference.h"
#include "nsWrapperCache.h"
#include "nsPluginArray.h"
class nsPIDOMWindow;
class nsPluginElement;
class nsMimeType;
class nsMimeTypeArray MOZ_FINAL : public nsISupports,
@ -73,11 +73,6 @@ public:
virtual JSObject* WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aScope) MOZ_OVERRIDE;
void Invalidate()
{
mPluginElement = nullptr;
}
const nsString& Type() const
{
return mType;
@ -92,8 +87,11 @@ public:
protected:
nsWeakPtr mWindow;
// Weak pointer to the active plugin, if any.
nsPluginElement *mPluginElement;
// Strong reference to the active plugin, if any. Note that this
// creates an explicit reference cycle through the plugin element's
// mimetype array. We rely on the cycle collector to break this
// cycle.
nsRefPtr<nsPluginElement> mPluginElement;
uint32_t mPluginTagMimeIndex;
nsString mType;
};

View File

@ -282,16 +282,7 @@ NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsPluginElement)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsPluginElement)
NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
// Invalidate before we unlink mMimeTypes
tmp->Invalidate();
NS_IMPL_CYCLE_COLLECTION_UNLINK(mMimeTypes)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsPluginElement)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_TRACE_WRAPPERCACHE(nsPluginElement)
NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE_1(nsPluginElement, mMimeTypes)
nsPluginElement::nsPluginElement(nsWeakPtr aWindow,
nsPluginTag* aPluginTag)
@ -301,11 +292,6 @@ nsPluginElement::nsPluginElement(nsWeakPtr aWindow,
SetIsDOMBinding();
}
nsPluginElement::~nsPluginElement()
{
Invalidate();
}
nsPIDOMWindow*
nsPluginElement::GetParentObject() const
{
@ -425,11 +411,3 @@ nsPluginElement::EnsureMimeTypes()
mMimeTypes.AppendElement(new nsMimeType(mWindow, this, i, type));
}
}
void
nsPluginElement::Invalidate()
{
for (uint32_t i = 0; i < mMimeTypes.Length(); ++i) {
mMimeTypes[i]->Invalidate();
}
}

View File

@ -74,7 +74,6 @@ public:
NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(nsPluginElement)
nsPluginElement(nsWeakPtr aWindow, nsPluginTag* aPluginTag);
virtual ~nsPluginElement();
nsPIDOMWindow* GetParentObject() const;
virtual JSObject* WrapObject(JSContext* aCx,
@ -102,7 +101,6 @@ public:
protected:
void EnsureMimeTypes();
void Invalidate();
nsWeakPtr mWindow;
nsRefPtr<nsPluginTag> mPluginTag;