Tag Archives: kernel

Making USB Great Again with USBFILTER – a USB layer firewall in the Linux kernel

Posted on August 4, 2016 by

Our paper “Making USB Great Again with USBFILTER” has been accepted by USENIX Security’16. This post provides a summary of usbfilter. For details, please read the damn paper or download the presentation video/slides from USENIX website. I will head to … Continue reading →

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gcc, llvm, and Linux kernel

Posted on March 12, 2016 by

This post talks about what happened recently in the Linux kernel mailing list discussion. While this post does not dig into compiler internals or the whole picture between the Linux kernel and compilers, we discuss 2 specific issues from gcc … Continue reading →

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Defending Against Malicious USB Firmware with GoodUSB

Posted on December 3, 2015 by

Finally, 4 months after our paper was accepted by ACSAC’15, I could now write a blog talking about our work – GoodUSB, and release the code, due to some software patent bul*sh*t. (I sincerely think software patent should be abolished … Continue reading →

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Linux kernel hacking – one relay file for all CPUs

Posted on November 16, 2015 by

I wrote a post about kernel relay 2 years go (https://davejingtian.org/2013/06/29/relay-linux-kernel-relay-filesystem/). However, I have realized that I did not understand relay until recently when I was debugging a relay-related bug. Though I was working on RHEL 2.6.32 kernel, this post … Continue reading →

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Linux kernel hacking – support SO_PEERCRED for local TCP socket connections

Posted on October 6, 2015 by

In my old post (https://davejingtian.org/2015/02/17/retrieve-pid-from-the-packet-in-unix-domain-socket-a-complete-use-case-for-recvmsgsendmsg/), we talked about how to retrieve the peer PID from Unix domain socket using struct ucred. A more smart way to do this is using getsockopt() syscall with option SO_PEERCRED directly. As you expected (or … Continue reading →

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How Linux kernel works – in 4 sentences

Posted on September 4, 2015 by

I found this in “Understanding the Linux Kernel” (ULK). I believe I have seen a lot of analogies in computer science. But this one is “Simply the Best”. I am not going to put anything here except the original analogy … Continue reading →

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Linux kernel I/O Stack Diagram 2

Posted on August 21, 2015 by

https://www.thomas-krenn.com/en/wiki/Linux_Storage_Stack_Diagram

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