I'm kind of curious what Alex meant by this, as the security problems relating to io_uring are, to my knowledge, unrelated to the user-space program. It makes sense if you want to disable the feature in your own kernel or remove potential sandbox escape attack surface, but it's like saying "You might want to avoid win32k if you want to use features with a good security track record" (and I know this is kind of apples to oranges but you get the point).
IIUC io_uring surfaced a bunch of pre-existing-but-rarely-hit code paths that had issues, which was widely taken to mean “io_uring has issues”. Google also disabled it on all machines in GCP, not clear if Google disabled it because of the same issues, or some other thing. The aforementioned issues have been fixed.
>Not sure what questions Microsoft have to answer.
The only thing I could think of is if it was a driver update, the driver has to be "WHQL" signed. WHQL stands for "Windows Hardware Quality Lab" -- what quality are they ensuring? (spoiler alert from my time at Microsoft: it's not terribly robust :p )
It's not realistic for Microsoft to test drivers in a manner that represents real-world usage, but perhaps they need to start doing some basic "it works with whatever integrated agent/etc is required" testing as a requirement for signing a driver.
If it was a user-mode update? Yeah no real fault on Microsoft here.
From what I heard Crowdstrike just updated their DB file, which means the bug was alreadyq there, waiting for someone to trigger it with a "low risk" quick roll out.
I wonder if this affects tvOS as well. I got my first Apple TV from a friend, wiped it, and recently bought a second brand new Apple TV.
My girlfriend was attempting to install an app on the new ATV and it prompted for my friend’s Apple ID to log in. The only association this new ATV should have is to my ID which is logged in on both devices.
>While we are many missing language features away from this being the case, the noalias case is also magic descended upon box itself, with no user code ever having access to it.
Well, they work on the compiler, so that's one reason I guess. Also the fact that it's magic is no secret and this is not the only way in which it is (the most important is probably the DerefMove behaviour that's mentioned in the article, too). There's been many discussions around this in the past
>You do not need a CPU upgraded console to use this patch and having one does not provide any additional performance gains that I've been able to measure during testing.
And this:
>This provided a 10% increase in transfer speeds for consoles running the stock IDE cable and up to a 300% increase (theoretically, the actual transfer speeds depend greatly on the size of data being transferred) for consoles with an upgraded IDE cable.
And this (again from the GitHub repo):
>If your console has 128MB of RAM this patch will utilize the extra RAM available which will enable use of 720p and 1080i video modes as well as increase the size of in-memory caches for textures and geometry. The size increase for the texture and geometry caches will significantly reduce pop-in issues to the point of being almost non-existent.
For just 480p you can overclock the GPU on a stock console and use a different IDE cable. I think the remark about the SSD was unintentionally misleading -- perhaps he did mean the combo of 80pin + SSD though.
It does not require an overclocked CPU (he states that the CPU was not the bottleneck), and the increased RAM is only required if you want resolutions of 720p or higher.
I relayed the feedback though, he might update the blog post to make these points more explicit.
It says in the article that the idea behind this implementation is that if the tag is swapped it breaks the authentication since the glue is involved in authenticating. NFC/RFID chips can just be swapped from a real product to a fake one as-is.
>What prevents somebody from scanning it and reconstructing the position of the metal pieces?
You're talking about very, very small pieces of metal whose position/orientation is not deterministic when laying the glue and that information is combined with the tag itself to present some kind of challenge response.
Yeah if I’m understanding the article correctly it’s not that the glue is pre-printed with a specific code but rather the glue has a bunch of particles suspended in it and take on an arbitrary pattern when used. Conceptually similar to https://trmm.net/Glitter/ but at a much smaller scale.
Why is it not possible to embed the NFC tag in a destructible medium? Like those annoying stickers that you cannot peel without ripping?
If you use that, then the only way to move the NFC tag to another item would be to cut it out of the original item (including the original adhesive). But this attack also works against the technique in the article.
Regarding the orientation, I understand that it is nondeterministic in the original, but what prevents an attacker from copying it deterministically? Is it just that technology is not good enough to manipulate such small pieces of metal? How long will this limitation persist?
Yes, like other similar tamperproofing options (glitter, vacuum-sealed colored beads, etc) it's trivial, cheap and fast to get a random pattern, but absolutely impractical to control the pieces to get any specific pattern - perhaps someone like a microsurgeon could manipulate them properly given enough time, but that would take an absurd time (since there are many tiny pieces which each need to be manipulated within a gooey substance where each movement disturbs previous ones as well) and be absurdly expensive, and nobody has a "printing" technology to do it in a cost-efficient way.
Perhaps in future someone could develop an advanced combination of 3d printer and pick&place machines that could do it, but such future potential doesn't disqualify this tech from currently detecting counterfeiting of fancy shoes or something.
Why would you need a 3D printer or pick&place machines? You can just do it photolithographically.
Coat a piece of glass with a thin layer of metal. Put a photoresist on top. Project the desired pattern onto it with UV light. Wash the unhardened photoresist away and etch the unnecessary metal.
Now you've got metal in exact the spots you'd like, of exactly the thickness you'd like. You can get the accuracy down to a few hundred micrometers for cheap today.
That would work only for a planar distribution of material. A 3D distribution would require multiple layers (I guess it might quickly become infeasible if it requires thousands of layers).
In the case of 3D arrangements, I think some substrate materials (and also some properties of the particles) would be very difficult to get using photolithography (or some kind of micro 3D printing).
In the case of 3D arrangements, you don't necessarily need to create all the layers photolithographically. You might be able to flatten N layers into 1 layer, then add a plastic coating equivalent to N-1 layers ontop, then repeat that. You'll have a very similar result to every layer being separate.
Imagine e.g. the "multiple layers of cardboard cutouts" scenery in theater vs it actually being 3D.
I don't know much about photolithography, but doesn't it rely on relatively expensive fixed masks prepared for each layer?
Assuming that doing the process you describe is sufficient, what's the ballpark of what "for cheap" means for you if you needed to print 1000 different fake tags, assuming many layers of "the desired pattern" to print the metal flakes?
> doesn't it rely on relatively expensive fixed masks prepared for each layer
If you need perfectly sharp edges and high precision, sure. But I'm sure in this case that'd be unnecessary.
> Assuming that doing the process you describe is sufficient, what's the ballpark of what "for cheap" means for you if you needed to print 1000 different fake tags, assuming many layers of "the desired pattern" to print the metal flakes?
I described in another comment an additional way to quantize the layers to reduce the repetition steps, which would reduce costs further.
Regarding costs, you could fake a THzID chip for about 500€ per fake. Not cheap enough to do it for household items, but if you're faking designer bags, clothing, sneakers, or electronics, it'd be absolutely worth it.
With the right techniques it's often possible to remove those annoying stickers without ripping them. Some of the techniques involve using a solvent or very thin and slippery blade. They are supposed to be resistant against that, but in practice a lot of time not enough.
NFC tag usually consists of two parts very tiny IC (small piece of silicon the size of sand grain) and antenna (a piece of metal foil in a fancy shape). You could make an NFC tag where attempting to remove it rips antenna, but that wouldn't destroy the IC. It's probably a matter of product price and quantities whether, counterfeiting it by reattaching the NFC chip to a new antenna is economically viable. As the process is not only possible it's performed at the NFC tag factory at very large quantities at very low cost. It might also be possible to repair parts of broken antenna assuming area around IC is undamaged.
So overall you get simplicity and cost of regular tamper resistance stickers, with better resistance against solvent and blade attacks, and security properties closer to what you get from secure NFC chip (except you can't perform more complicated cryptographic operations like signing arbitrary data).
> Is it just that technology is not good enough to manipulate such small pieces of metal? How long will this limitation persist?
I would expect that at any point in future, whatever the best controlled manufacturing technique invented are, it will be possible to create uncontrolled pattern at finer scale, or at least much cheaper. Unless we reach the point where maintaining stable state without deteriorating becomes a problem, or the quantity of data for storing and processing becomes impractical.
