Author Archives: daveti

About daveti

Interested in kernel hacking, compilers, machine learning and guitars.

Ubuntu Kernel Build Again

Posted on November 7, 2019 by daveti

I wrote two blog posts about Linux kernel build on Ubuntu [1,2]. There is also an official wiki page talking about the same thing [3]. Still, things are broken when I try to create a homework assignment for my class. … Continue reading →

Posted in IDE_Make, Linux Distro, OS | Tagged build, growpart, kernel, kvm, Linux, lockdown, lsblk, parted, QEMU, qemu-img, resize2fs, sign, Ubuntu | 1 Comment

USB Fuzzing: A USB Perspective

Posted on July 17, 2019 by daveti

Syzkaller [1] starts to support USB fuzzing recently and has already found over 80 bugs within the Linux kernel [2]. Almost every fuzzing expert whom I talked to has started to apply their fuzzing techniques to USB because of the … Continue reading →

Posted in Security | Tagged drd, fuzzing, HCD, kernel, Linux, OTG, QEMU, security, syzkaller, UDC, USB | 3 Comments

Speculations on Intel SGX Card

Posted on March 25, 2019 by daveti

One of the exciting things Intel has brought to RSA 2019 is Intel SGX Card [2]. Yet there is not much information about this coming hardware. This post collects some related documentation from Intel and speculates what could happen within … Continue reading →

Posted in Security | Tagged enclave, EPC, intel, kvm, sgx, vca | Leave a comment

Syscall hijacking in 2019

Posted on February 25, 2019 by daveti

Whether you need to implement a kernel rootkit or inspect syscalls for intrusion detection, in a lot of cases, you might need to hijack syscall in a kernel module. This post summorizes detailed procedures and provides a working example for … Continue reading →

Posted in OS, Security | Tagged aarch64, kernel, Linux, syscall, x86_64 | 1 Comment

Kernel build on Nvidia Jetson TX1

Posted on December 31, 2018 by daveti

This post introduces native Linux kernel built on the Nvidia Jetson TX1 dev board. The scripts are based on the jetsonhacks/buildJetsonTX1Kernel tools. Our target is JetPack 3.3 (the latest SDK supporting TX1 by the time of writing). All the scripts … Continue reading →

Posted in Embedded System, gpu, OS | Tagged jetpack, jetson, kernel, l4t, Linux, nvidia, tegra, tx1 | Leave a comment

Setting up Nvidia Jetson TX1

Posted on September 23, 2018 by daveti

Starting from this post, I will share my learning and hacking experience on Nvidia Jetson TX1 dev board. This post discusses the installation issue of JetPack [4] and post-installation configurations for TX1. We assume users follow the JetPack 3.3 installation … Continue reading →

Posted in Embedded System, gpu | Tagged cuda, dhcp, gpu, jetson, nmcli, nvcc, nvidia, tx1 | Leave a comment

Hacking Valgrind

Posted on July 7, 2018 by daveti

This post talks about 3 commits I have recently added into my own valgrind tree [1], including the support for fsgsbase instructions, rdrand/rdseed instructions, and adding a new trapdoor (client request) to support gdb-like add-symbol-file command. Note that all these … Continue reading →

Posted in Dave's Tools, Programming | Tagged add-symbol-file, cpuid, fortanix, fsgsbase, gdb, rdrand, rdseed, trapdoor, valgrind, x86_64 | Leave a comment

Valgrind trapdoor and fun

Posted on July 7, 2018 by daveti

Valgrind has a client request mechanism, which allows a client to pass some information back to valgrind. This includes asks valgrind to do a logging in its own environment, tells valgrind a range of VA being used as a new … Continue reading →

Posted in Programming, Security | Tagged trapdoor, valgrind, VEX, x86_64 | Leave a comment

Some notes on SGX OwnerEpoch and Sealing

Posted on June 24, 2018 by daveti

Intel SGX has been there in the market for while. Yet there are still a lot of misundrestandings and mysteries about this technology. This post provides an introduction to Intel SGX OwnerEpoch and Sealing, discusses their security impacts, and speculates … Continue reading →

Posted in Security | Tagged egetkey, OwnerEpoch, Sealing, sgx, SGXv2, soe | Leave a comment

Kernel Code Execution Time Measurement (kcetm)

Posted on May 20, 2018 by daveti

This post mainly talks about the correct usage of tsc counters provided by Intel x86/x86-64 architectures to measure the Linux kernel code execution time. Most of the content here is borrowed/inspired from [1]. Note that this is NOT a post … Continue reading →

Posted in Dave's Tools, OS, Programming | Tagged cpuid, intel, kcetm, kernel, lfense, Linux, rdtsc, rdtscp, tsc | 1 Comment