Debugging FFS Mount Failures

This report was written by Maciej Grochowski as a part of developing the AFL+KCOV project.

This report is a continuation of my previous work on Fuzzing Filesystems via AFL. You can find previous posts where I described the fuzzing (part1, part2) or my EuroBSDcon presentation.
In this part, we won't talk too much about fuzzing itself but I want to describe the process of finding root causes of File system issues and my recent work trying to improve this process.
This story begins with a mount issue that I found during my very first run of the AFL, and I presented it during my talk on EuroBSDcon in Lillehammer.

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LLDB Threading support now ready for mainline

Upstream describes LLDB as a next generation, high-performance debugger. It is built on top of LLVM/Clang toolchain, and features great integration with it. At the moment, it primarily supports debugging C, C++ and ObjC code, and there is interest in extending it to more languages.

In February, I have started working on LLDB, as contracted by the NetBSD Foundation. So far I've been working on reenabling continuous integration, squashing bugs, improving NetBSD core file support, extending NetBSD's ptrace interface to cover more register types and fix compat32 issues and fixing watchpoint support. Then, I've started working on improving thread support which is taking longer than expected. You can read more about that in my September 2019 report.

So far the number of issues uncovered while enabling proper threading support has stopped me from merging the work-in-progress patches. However, I've finally reached the point where I believe that the current work can be merged and the remaining problems can be resolved afterwards. More on that and other LLVM-related events happening during the last month in this report.

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Threading support in LLDB continued

Upstream describes LLDB as a next generation, high-performance debugger. It is built on top of LLVM/Clang toolchain, and features great integration with it. At the moment, it primarily supports debugging C, C++ and ObjC code, and there is interest in extending it to more languages.

In February, I have started working on LLDB, as contracted by the NetBSD Foundation. So far I've been working on reenabling continuous integration, squashing bugs, improving NetBSD core file support, extending NetBSD's ptrace interface to cover more register types and fix compat32 issues and fixing watchpoint support. Then, I've started working on improving thread support. You can read more about that in my July 2019 report.

I've been on vacation in August, and in September I've resumed the work on LLDB. I've started by fixing new regressions in LLVM suite, then improved my previous patches and continued debugging test failures and timeouts resulting from my patches.

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Adapting TriforceAFL for NetBSD, Part 3

Prepared by Akul Pillai as part of GSoC 2019.

This is the third report summarising the work done in the third coding period for the GSoC project of Adapting TriforceAFL for NetBSD kernel syscall fuzzing.
Please also go through the first and second report.

This post also outlines the work done throughout the duration of GSoC, describes the implications of the same and future improvements to come.

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GSoC 2019 Report: Implementation of compat_netbsd32 DRM ioctl/Getting DRM applications running under compat-linux

This article was prepared by Surya P as a part of Google Summer of Code 2019

To begin with where we left off last time, we were able to fix the suse131 package with this commit.This commit adds the GPU-specific bits to the package. And with that we had direct rendering enabled and working.I tested it out with glxinfo and glxgears applications.

Testing

In order to make sure that applications did not break with this commit,I tried Libreoffice and to no surprise everything ran as expected without any hiccups.

Then I had to make a choice between porting steam and implementing compat_netbsd32 but since steam had lot of dependencies which needed to be resolved and since implementation of compat_netbsd32 had much more priority I started with the implementation of compat_netbsd32.

Implementing compat_netbsd32 DRM ioctls - The Setup

For the Setup I downloaded i386 sets from the official NetBSD site and extracted it in the /emul directory. I ran some arbitrary programs like cat and ls from the emulated netbsd32 directory to make sure everything ran perfectly without any problems. I then tried running the 32bit glxinfo and glxgears application and to no surprise it kept segfaulting. I ktraced the application and identified the DRM ioctl that needed to be implemented.

Implementing compat_netbsd32 DRM ioctls - The Code

There were several functions which were required for the complete working of the compat_netbsd32 DRM ioctl. We implemented each and every function and had the code compiled. We then made sure that the code compiled both as a module and as well as a non module option with which the kernel can be built.I initially tested the code with 32bit glxinfo and glxgears , and the program didn't segfault and ran as expected.

Implementing compat_netbsd32 DRM ioctls - Testing

In order to test the code I built a test application leveraging the api’s provided in libdrm. It is a very simple application which initializes the DRM connection, setup and draws a gradient on screen and exits. I initially ran it against the native amd64 architecture, but to my surprise the application didn't work as expected. After some hours of debugging I realized that there can be only one DRM master and X was already a master. After exiting the X session and running the application, everything ran perfectly for both amd64 as well as i386 architectures.

What is done

• The Drm Ioctls implementation of Netbsd has been tested and verified
• The suse131 package has patched and updated (committed)
• Compat_netbsd32 DRM ioctls has been implemented (Merged)
• Subsequently DRM ioctls for emulated 32bit linux as well
• Created a Test GUI Application for the code (yet to PR)

TODO

• Create an ATF for the code and merge it into the tree
• Read the code, look for bugs and clean it up
• Port Steam and make it available in NetBSD

Conclusion

Completing the tasks listed in the TODO is of highest priority and would be carried over even if it exceeds the GSOC time period.

Last but not the least I would like to thank my mentors @christos and @maya for helping me out and guiding me throughout the process and Google for providing me with such a wonderful opportunity to work with NetBSD community.

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GSoC 2019 Report: Adding NetBSD KNF to clang-format, Final

This report was prepared by Manikishan Ghantasala as a part of Google Summer of Code 2019

This is the third and final report of the project Add KNF (NetBSD style) clang-format configuration that I have been doing as a part of Google Summer of Code (GSoC) ‘19 with the NetBSD.

You can refer to the first and second reports here:

1. Adding NetBSD KNF to clang-format, Part 1
2. Adding NetBSD KNF to clang-format, Part 2

About the project

ClangFormat is a set of tools to format C/C++/Java/JavaScript/Objective-C/Protobuf code. It is built on top of LibFormat to support workflow in various ways including a standalone tool called clang-format, and editor integrations. It supports a few built-in CodingStyles that include: LLVM, Google, Chromium, Mozilla, Webkit. When the desired code formatting style is different from the available options, the style can be customized using a configuration file. The aim of this project is to add NetBSD KNF support to clang-format and new styles to libFormat that support NetBSD’s style of coding. This would allow us to format NetBSD code by passing `-style=NetBSD` as an argument.

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Fuzzing NetBSD Filesystems via AFL. [Part 2]

This report was written by Maciej Grochowski as a part of developing the AFL+KCOV project.

Recently I started working on Fuzzing Filesystems on NetBSD using AFL.
You can take a look at the previous post to learn more details about background of this project.
This post summarizes the work that has been done in this area, and is divided into 3 sections:

1. Porting AFL kernel mode to work with NetBSD
2. Running kernel fuzzing benchmark
3. Example howto fuzzing particular Filesystem

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GSoC 2019 Report: Adding NetBSD KNF to clang-format, Part 2

This report was prepared by Manikishan Ghantasala as a part of Google Summer of Code 2019

This report encloses the progress of the project Add KNF (NetBSD style) clang-format configuration during the second coding period of GSoC 2019.

Clang-format

Clang-format is a powerful code formatter which is a part of clang. Clang-format formats the code either by a configuration file .clang-format or can be chosen from some predefined coding styles namely LLVM, Google, Chromium, Mozilla, WebKit.

The final goal of the project is to add a new style NetBSD along with them by patching the libFormat to support the missing styles and add the configuration according to NetBSD KNF.

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GSoC 2019 Report Update: Incorporating the memory-hard Argon2 hashing scheme into NetBSD

This report was prepared by Jason High as a part of Google Summer of Code 2019 [Read More] [0 comments]

 

Work-in-progress threading support in LLDB

Upstream describes LLDB as a next generation, high-performance debugger. It is built on top of LLVM/Clang toolchain, and features great integration with it. At the moment, it primarily supports debugging C, C++ and ObjC code, and there is interest in extending it to more languages.

In February, I have started working on LLDB, as contracted by the NetBSD Foundation. So far I've been working on reenabling continuous integration, squashing bugs, improving NetBSD core file support, extending NetBSD's ptrace interface to cover more register types and fix compat32 issues, and lately fixing watchpoint support. You can read more about that in my June 2019 report.

My July's work has been focused on improving support for NetBSD threads in LLDB. This involved a lot of debugging and fighting hanging tests, and I have decided to delay committing the results until I manage to provide fixes for all the immediate issues.

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Enchancing Syzkaller Support for NetBSD, Part 2

Prepared by Siddharth Muralee(@R3x) as a part of Google Summer of Code’19

As a part of Google Summer of Code’19, I am working on improving the support for Syzkaller kernel fuzzer. Syzkaller is an unsupervised coverage-guided kernel fuzzer, that supports a variety of operating systems including NetBSD. This report details the work done during the second coding period.

You can also take a look at the first report to learn more about the initial support that we added.

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Adapting TriforceAFL for NetBSD, Part 2

Prepared by Akul Pillai as part of GSoC 2019.

I have been working on adapting TriforceAFL for NetBSD kernel syscall fuzzing. This blog post summarizes the work done until the second evaluation.

For work done during the first coding period, check out this post.

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