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Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by rayiner on Friday November 02, 2018 @12:43PM (#18364487)
> "This is the main reason we released the exploit -- to show how reproducible it is," Brumley told us, "and help to kill off the SMT trend in chips."

Maybe what we should be killing off instead is exporting everything to the cloud and running untrusted native code willy nilly.

Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by jlebar on Friday November 02, 2018 @12:56PM (#18364630)
It's not just untrusted native code. A lot of these exploits in general are exploitable through js.

And I know there are folks on hn who think js is an abomination and noscript is the answer to all of life's persistent problems. "My web browser should be exclusively for reading text." But personally I'm not interested in taking us back to the 1990s.

Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by josefx on Friday November 02, 2018 @01:02PM (#18364697)
I don't need to be in the 1990s, I just wished websites wouldn't need to draw from ~200 untrusted sources and possibly worlds largest malware distribution channel to show some ads from even less trusted sources right next to badly formatted text.
Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by SolarNet on Friday November 02, 2018 @01:54PM (#18365143)
I mean the text is probably from poorly trusted sources as well but that's a different problem.
Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by dijit on Friday November 02, 2018 @06:56PM (#18367402)
but text has a limited attack scope compared to say: an entire interpreted language and DOM.
Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by y4mi on Friday November 02, 2018 @02:48PM (#18365613)
> I just wished websites wouldn't need to draw from ~200 untrusted sources

That's just how it is though. Even if you're using vanilla js.

Don't get me wrong, I know what you mean... it's just that it's really hard to actually find arguments for that... philosophy

At this point, I think it doesn't really matter as long as your site has a good ux.. which is obnoxiously hard to measure

Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by ahje on Monday November 05, 2018 @04:40AM (#18381030)
With Noscript enabled I have the power to chose what to trust and not to trust. That means I have gradual control over what runs and doesn't run, and can chose to only allow the bare minimum for getting a specific page to run. It's that simple.

JS is fine as a technology, but blindly executing every single piece of code on every single web page is simply not a good way of doing things.

Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by rayiner on Friday November 02, 2018 @01:01PM (#18364687)
In what ways could JS be limited to preclude such attacks? (E.g. no JIT compilation, cache flush after every opcode, etc.).
Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by josefx on Friday November 02, 2018 @01:13PM (#18364806)
No constant addition and removal of new APIs. Lockdown of special purpose APIs with explicit user request to unlock: 99.9999% of sites will never need WebGL, 99.9999% of sites don't need an Audio API. Modern JavaScript has the attack surface of Java and Flash combined and enabled by default, instead of hardening this against attacks browser are stuck in the same feature race they have been in since back when IE6 was still dominant browser.
Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by umanwizard on Friday November 02, 2018 @03:40PM (#18366069)
> cache flush after every opcode

This would make JS outrageously slow, like hundreds of times slower than it is now.

Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by rayiner on Friday November 02, 2018 @05:15PM (#18366843)
You don't need it to be very fast just to respond dynamically to some event handlers and whatnot. (The basic scripting stuff JS was intended for.)
Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by johannes1234321 on Sunday November 04, 2018 @08:28PM (#18379130)
You also don't need modern wheels, when just pulling a simple carriage wheels were invented for.

Modern JS engines are not written for playing funny tricks with "window.status" or "window.title" as in 1990, but for more complex applications.

Not all uses are useful, but that's to subjective. As with wheels.

Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by illumin8 on Friday November 02, 2018 @02:37PM (#18365521)
Any cloud provider with sufficient security doesn't allow customers to share SMT cores anyway. For example, AWS hard partitions their physical servers, which is why you can get exactly 16 m4.xlarge instances, 8 m4.2xlarge, 4 m4.4xlarge, 2 m4.8xlarge, or 1 m4.16xlarge instances on a physical box.

I do predict that the VPS providers will see some nasty side-channel attacks in the coming years due to the way they've chosen to share SMT between customers to reduce their costs and overprovision their hardware.

Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by jxy on Friday November 02, 2018 @01:46PM (#18365096)
Physical containment would work fine. Given the current small footprint of computing modules, we could just run each separate untrusted cloud apps from a node the size of a pi0. All we need is a high throughput interconnect with a well defined interface to exchange information.

... wait, that sounds like plan9's dream

Re:Intel CPUs impacted by new PortSmash side-channel vulnera... by esotericn on Friday November 02, 2018 @01:09PM (#18364769)
Yep.

I understand that half the world runs on this stuff nowadays. That doesn't make it any less insane.

Your customer database is in a random DC somewhere halfway across the world running on the same box as some other arbitrary code.

Nice one. It's Web Scale(tm).