Linux Kernel Exploitation Part 2: Buddy Allocator and SLUB Allocator


I will continue to talk about the exploitation of CVE-2017-7308. In this post, I will discuss the implementation details of buddy allocator and SLUB allocator in Linux-4.10.6. I will show how to put the victim object (struct packet_sock in this post) next adjacent to the vulnerable buffer (packet rv_ring buffer in previous post).
In [3], a general abstraction of Linux Kernel memory management is given as following picture. From the picture, we can find that two types of allocators (slab allocator and buddy allocator) are provided for Linux kernel functions. For both allocators, I will give some debugging info to give a straight view on how those objects are allocated and shaped in memory combined with some explanation on the source code.
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Linux Kernel Exploitation Part 1: Setting Up Debugging Environment


These days I think there is still necessity to write a tutorial series on Linux Kernel exploitation and hope to summarize the kernel exploitation techniques as following:
(1) Kernel Debugging
(2) Return-oriented-Programming in Kernel
(3) Kernel Mitigation: KASLR, SMEP, SMAP
(4) Kernel Space Memory Allocator: SLAB Allocator
In this post, I will introduce how to debug a Linux Kernel via CVE-2017-7308 [1], including setting up debugging environment, root cause analysis and exploit primitive analysis.
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Virtual Function


The virtual table is the key factor that achieves polymorphism in C++. This post will talk about the virtual table and its structure in C++. More particularly, I will introduce the virtual functions under Linux and Windows. All tests are done on 64-bit platform. 32-bit platform is a little bit different but the basic idea is similar.
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