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Comment by haberman | Hacker News Reader

I could be wrong, but I take the "bug/flaw" language to mean this: the processor is doing exactly what it was designed to do (unlike the Pentium FDIV bug, for example). A new class of exploit was recently discovered, and these CPUs are vulnerable to this new exploit. But there was no bug in how these CPUs were implemented, and the only design flaw is that they failed to withstand a new class of exploit that was not known at the time they were designed.

(I don't have any information that could confirm/deny this, it's just how I interpret their verbiage).

I don't get the sense that they are trying to deceptively contradict only part of the previous statement.

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It's kind of semantics though isn't it? If I write a piece of software that follows the spec and fulfils the customer's need, but then someone tries to do something with it that we hadn't thought of and that results in a security hole... around here we call that a bug, a flaw, something we missed. Maybe it's reasonable to have not spotted the bug, but that wouldn't make it not a bug/flaw.

Yeah I agree there is a line there somewhere. If someone sells you a safe and it can be opened with a ballpoint pen, that seems like a flaw. If someone sells you a safe and it can be opened with a military grade laser, that's sort of expected. If someone sells you a safe and it can be opened with a cheap consumer gadget, but that gadget is complex and was unforeseen when the safe was designed, what do you say about that? The last one seems like the closest analogy.

Another example: would you say that MD5 is buggy/flawed?

I guess overall I think this is fair to call a "flaw" but not a "bug."

> I guess overall I think this is fair to call a "flaw" but not a "bug."

Yes I agree, it's not a bug in the sense of a silly mistake that slipped through development and testing. It's a flaw / attack-vector that no-one thought of... until now.

Reminds me of dieselgate. "Our product is ok unless operated out of spec" didn't work, iirc.

I think that analogy paints a pretty clear picture, this is a flaw because it's undesirable behavior in unexpected circumstances. A bug is unexpected behavior in expected use-cases.

I was about to say something like, "Well, in a broad sense they introduced protection features to x86 to prevent modification or disclosure of memory contents across process boundaries...and that's broken, therefore bug."

However, looking at the reference manual for the 80386 [1], and a modern version of their x64 manual [2], they don't actually say it's for security:

Original: "6.1 Why Protection? The purpose of the protection features of the 80386 is to help detect and identify bugs. The 80386 supports sophisticated applications that may consist of hundreds or thousands of program modules..."

Modern: "The IA-32 architecture’s protection mechanism recognizes four privilege levels, numbered from 0 to 3, where a greater number mean less privilege. The reason to use privilege levels is to improve the reliability of operating systems."

So it's more like someone sells you a box with a lock on the front that looks a lot like a safe and all of the individual hinges and pins and whatnot are guaranteed to some degree, but they never actually say it's OK to lock your stuff inside.

[1]https://css.csail.mit.edu/6.858/2013/readings/i386.pdf

[2]https://www.intel.com/content/www/us/en/architecture-and-tec...

I'd agree. The implementation conforms to the specification, so it's not a bug. The specification is flawed.

> It's kind of semantics though isn't it?

I never understood how this sentence became a defense. Yes, yes it is. It is semantics. Everything is semantics. The difference between getting fired and getting laid off is semantics, and everybody cares about it and recognizes it. The difference between "I'll pick you up at 5pm" and "I promise I will pick you up at 5pm even if my car breaks down and the train gets derailed" is semantics. Calling something "semantics" isn't a defense to your argument; it's often more like a concession. (And the difference between a defense and a concession is, as I'm sure you realize, also semantics...)

Since we're being semantic about things, lets be clear that when someone says it's all "semantics" they mean that the person is engaging in a semantic dispute. This is a type of argument that has a specific meaning-

> A semantic dispute is a disagreement that arises if the parties involved disagree about the definition of a word or phrase, not because they disagree on material facts, but rather because they disagree on the definitions of a word (or several words) essential to formulating the claim at issue.

When someone is "arguing semantics" they are often trying to obfuscate the original issue being discussed.

In this specific case the argument is being made that Intel is trying to use a different meaning for the word "bug" that favors them. redcalx is then stating the general definition of "bug" in an attempt to point out how limiting and nonstandard their definition is.

> When someone is "arguing semantics" they are often trying to obfuscate the original issue being discussed.

Well (and the irony is not lost on me here), this wasn't part of the definition of a semantic dispute that you just presumably quoted... it was just something you tacked onto it afterward. And the entire problem is that to you a semantic dispute might imply the original issue is being obfuscated, whereas to the other person it might imply you are trying to stretch your own ideas to where they wouldn't apply.

Read your own definition: you said a semantic dispute is when they disagree on essential words. Not fluff words. People don't need to disagree on facts to have legitimate disagreements about about their interpretations and consequences. We all agree the CPU behaved in an undesirable way. There is no debate there, but that fact was insufficient to get us anywhere. What we disagree on is whether that is a "bug", which matters to all sides because it has consequences as who is to resolve the issue and how.

> In this specific case the argument is being made that Intel is trying to use a different meaning for the word "bug" that favors them.

[Edit: I misread part of the comment here; see below.]

If it's "unintended behavior", then, sure, the CPU has "bugs", but that's a pretty useless definition that gets you nowhere (especially legally). If it's "does not perform as specified", which at least to me is a more logical choice, then I'm afraid I have not seen a shred of evidence that they ever claimed memory contents are immune from CPU timing/cache/etc. effects.

> ...you cannot seriously expect this to be a convincing argument without offering your own kosher definition (read: semantics) of "bug".

It's kind of hilarious that the only reason you can claim this is because of your selective editing. The whole statement you are responding too is this-

> In this specific case the argument is being made that Intel is trying to use a different meaning for the word "bug" that favors them. redcalx is then stating the general definition of "bug" in an attempt to point out how limiting and nonstandard their definition is.

Since you missed it the first time redcalx is already making the argument for me. I don't need to supply a separate version of the definition, I just need you to read the original message you were responding too.

Shoot, apologies for that, this was a silly reading error on my part... I quickly read that comment while outside and didn't realize 'redcalx' was referring to the user above, and instead somehow my brain just glossed over that part as a typo.

Disregard that part of my comment and look at all the rest of what I've actually been saying. The problem I have been trying to point out with the definition (as in the last comment, but I'll repeat here) is that the definition of a "bug" might be "just semantics" to you, but that doesn't make it irrelevant; those semantics make all the practical differences here. If you consider any undesirable behavior in unintended situations to be a "bug", then it sure sounds good, but won't get you anywhere, given that practically anything you buy can be used in weird ways with unforeseen (and hence unintended) consequences. If you consider a "bug" to be a deviation from the manufacturer's specified behavior, then it's obviously more limiting, but I would expect it's closer to the semantics a court would use to decide whether to hold the manufacturer responsible.

My limited understanding is that the vulnerability is due to kernel memory protections not being applied during speculative execution, when the CPU is trying to second guess what the next instructions might be.

Unless you are in PR, any reasonable person would expect a CPU touted as having kernel memory protection to protect it under all circumstances. I'm sure that the people who wrote the speculative execution code would have included that protection had they thought of it, and all developers would class it's omission as a bug. So yes, this is yet another example of awful PR, trying to cover up a serious mistake with careful language that makes it seem not their fault.

My policy when I make a mistake is immediate disclosure, along with two commitments: to put the mistake right, and to amend processes to prevent similar mistakes in the future. It isn't clear how Intel can put this right, but perhaps a good discount on replacement parts might help. And they can certainly implement processes to catch such omissions in the future.

So this press release (particularly combined with reports of execs selling stock) are appalling. Intel have badly damaged their brand, and I'll never buy another Intel processor again.

I do not think the processor was designed to improperly unwind from speculative execution, such that the state after failed speculation is not identical to the state prior to speculation.

But yeah, this an old discussion, and a deep rabbit hole. There's many layers to consider bugs at. Implementation can differ from developer intention, developer intention can differ from group agreement, group agreement can differ from design document, design document can differ from product development intention, and product development intention can differ from communicated functionality.

I'm betting this would be implementation differing from developer intention, although I would consider (almost) all of the above to be bugs.

This feels pretty deceptive when the most relevant competitor, amd, is not susceptible...

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