Advanced Windows Kernel Debugging Techniques

Mon, 10 Mar 2025 00:00:00 +0000

Kernel debugging is a different animal from the user-mode debugging most developers grow up with. You can’t just attach a debugger to a live kernel the way you’d attach to a misbehaving process, because the kernel is the thing that’s supposed to be managing every process on the box, including the debugger’s own. If it halts, everything halts. So Windows solves this the old-fashioned way: two machines. One is the “target,” the system whose kernel you actually want to inspect. The other is the “host,” running WinDbg, connected over a transport that survives the target being frozen mid-instruction: a network link, a serial cable, or USB. When you set a breakpoint and it hits, the entire target machine stops, not just one process, and control passes to your host over that wire. That’s the mental model to keep in the back of your head for everything that follows: you’re not debugging a program, you’re debugging an operating system from the outside, one machine talking to another.

Introduction to Windows Syscalls

Tue, 17 Sep 2024 00:00:00 +0000

What Are System Calls, Really?

Every time your program does something that touches the outside world, opening a file, allocating memory, talking to the network, waiting on another thread, it’s asking the operating system to do that work on its behalf. Your program doesn’t get to poke the disk controller or the network card directly. It can’t, by design. The CPU itself enforces this separation through privilege rings: user-mode code (ring 3 on x86/x64) runs with a restricted set of permissions, while the kernel (ring 0) runs with full access to hardware and memory. A system call is the formal, controlled doorway between those two worlds.

Windows on Prepakis Georgios | Kernelstub | Security Researcher

Advanced Windows Kernel Debugging Techniques

Introduction to Windows Syscalls

What Are System Calls, Really?