Bug 90028 – There is not an exit to escape out of the recursive call written wrong (freeze on bonds.finam.ru)

• Component: JavaScriptCore
• Status: UNCONFIRMED

[Hojong Han]

Webkit is locked up while loading "http://bonds.finam.ru/issue/info".
What I've analyzed is that "http://bonds.finam.ru/scripts/lizard/library/base.js" causes sort of recursive call.

Take a look into script codes below.
======================================================================================
Object.prototype.toString = Array.prototype.toString = Object.prototype.ToString = Array.prototype.ToString = function() {
	var cont = [];
	for (var k in this) {
		if (cont.length) cont[cont.length-1] += ",";
		var v = this[k];
		var vs = '';
		if (typeof(v) != 'undefined') {
			if (v != null) {
				if (typeof(v.constructor) != 'undefined') {
					try{
					if (v.constructor == String) {
						s = v.split('\\').join('\\\\').split('"').join('\\"');
						vs = '"'+s + '"';
					} else {
						vs = v.toString();
					}
					}
					catch(err)
					{
					}
	... skip ...
}
======================================================================================

Chrome, FireFox, some other browsers are not frozen while loading "http://bonds.finam.ru/issue/info".
Is there any other way to detour this kind of problem?

[Gavin Barraclough]

We used to support a timeout mechanism, but with WebKit2 we instead rely on the UI process shooting down the web process if it runs off out of control.

It would be nice to have an efficient (non-polling) mechanism to be able to asynchronously interrupt execution.  These bugs are related:
    https://bugs.webkit.org/show_bug.cgi?id=12637
    https://bugs.webkit.org/show_bug.cgi?id=41765

The timeout mechanism may still work in the old JIT & classic interpreter, but probably won't be around for long.  Mark Lam may be looking at an efficient mechanism to break out of JIT code based around DFG JIT speculation watchpoint, at some point in the near future.

cheers,
G.

[Alexey Proskuryakov]

Reproduced with Safari 5.1.7.

The freeze itself needs to be looked into, as well - this is a fairly important site. What makes us freeze while other browsers do not?

[Gavin Barraclough]

Oh, sorry, maybe I misunderstood the problem – I read it as other browsers timing out & assumed a content issue, but re-reading I see that may not be the case.