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pawkolor pawkolor is offline
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Default randomization kernel protection

Hello I'm not too much familiar with IT and programing but I would ask about new feature.What advantage will be this change what Theo is doing .

https://marc.info/?l=openbsd-tech&m=149732026405941
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phessler@ answered this question in the comments to the article in the OpenBSD Journal.
Quote:
Before this change, all kernels would have precisely the same memory layout. If you know a single symbol, you can calculate everything else.

The purpose of this, is to defend against attacks that use that information to attack. If every machine has a unique layout per boot, then those attacks cannot succeed.
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pawkolor pawkolor is offline
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Why Theo do this now not 10 years ago.Somebody from NSA use this method to hack system.
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There was also this article in bleepingcomputer.com, and where I first learned about it.

OpenBSD Will Get Unique Kernels on Each Reboot

It explains the difference in KARL and ASLR — Address Space Layout Randomization, which has been implemented in Linux:
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For clarity, your link references KASLR - "Kernel ASLR."

ASLR is not new, having been initially developed for Linux PaX in 2001 and deployed in OpenBSD in 2003, with other operating systems following over time. (Wiki)

Last edited by jggimi; 1 Week Ago at 03:43 PM. Reason: added link
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I wasn't clear enough and going by what the article stated:

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KARL should not be confused with ASLR — Address Space Layout Randomization — a technique that randomizes the memory address where application code is executed, so exploits can't target a specific area of memory where an application or the kernel is known to run.
At any rate, it was the deciding factor in my building another OpenBSD box after not having one for several years. Having an OpenBSD box in addition to just FreeBSD boxen has its merits as well.
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