Neat. The author is about to stumble onto a secret.

> In Sum# > Abstractions. They don’t exist in assembler. Memory is read from registers and the stack and written to registers and the stack.

Abstractions do not exist periodi. They are patterns, but these patterns aren’t isolated from each other. This is how a hacker is born, through this deconstruction.

It’s just like the fact that electrons and protons don’t really exist. but the patterns in energy gradients are consistent enough to give them names and model their relationship. There are still points where these models fail (QM and GR at plank scale, or just the classical-quantum boundaries). It’s gradients all the way down, and even that is an abstraction layer.

Equipped with this understanding you can make an exploit like Rowhammer.

https://en.wikipedia.org/wiki/Row_hammer

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wiz21c 7 hours ago | parent [-]

Abstractions pretty much exist and in assembler they matter even more because the code is so terse.

Now, there are abstractions (which exist in your brain, whatever the language) and tools to represent abstractions (in ASM you've got macros and JSR/RET; both pretty leaky).

	▲	Kiboneu 4 hours ago \| parent [-]
		That wasn’t my point. You almost got there when you wrote “there are abstractions (which exist in you brain, whatever the language)”. And your point on leaky abstractions is exactly the indication that they exist in your mind, not out there. My point is that we settle with what we see for convenience/utility and base our models on that. We build real things on top of these models. Then the result meets reality. If only that transition were so simple. When an effect jumps unexpectedly between layers of abstraction we call it an abstraction leak. As you mentioned. The correct response is to re-examine these leaks and make other frameworks to cover the edge cases, not to blame the world. Hackers actively seek these “leaks” by suspending assumptions that arise out of the abstractions that humans tend to rely on. I’m not surprised that my OP got downvoted. It can be very upsetting when one’s conceptual frameworks are challenged without prescription. No one even mentioned the specific example that I referenced. Well, if they can’t parse it, they don’t deserve it. Keeps me in the market.