Google Summer of Code 2019 Mentor Summit

Author: Kamil Rytarowski

E-mail: kamil@netbsd.org

Date: October 19th 2019

Place: Munchen Marriott Hotel, Munchen, Germany

Kamil Rytarowski (born 1987)

Krakow, Poland

NetBSD user since 6.1.

The NetBSD Foundation member (== developer) since 2015.

Work areas: kernel, userland, pkgsrc.

Interest: NetBSD on desktop and in particular NetBSD as a workstation.

The current activity in 3rd party software:

• LLVM committer.
• GDB & binutils committer.
• NetBSD maintainer in qemu.

The first time mentor during GSoC 2018.

• Lightning introduction to NetBSD
• NetBSD and Google Summer of Code
• Previous releases of NetBSD

NetBSD 9

• hardware platforms
• virtualization
• quality improvement tools (sanitizers, fuzzers, debuggers, static code analysis)
• security hardening
• graphics
• filesystems
• networking stack and packet filters
• other improvements, removals etc...

NetBSD is a free, fast, secure, and highly portable Unix-like Open Source operating system.

It is available for a wide range of platforms, from large-scale servers and powerful desktop systems to handheld and embedded devices.

How does NetBSD compare to Linux?

• Independent kernel and userland
• Whole codebase maintained in a single source tree
• BSD licensed

How does NetBSD compare to FreeBSD and OpenBSD?

• Focus on portability to as many hardware platforms (ports) as possible
• Clean code and portability over x86/x86_64 and performance driven development [FreeBSD]
• Usability, features and rational security hardening over security driven development [OpenBSD]

PowerPC, Alpha, SPARC, MIPS, SH3, ARM, amd64, i386, m68k, VAX, RISCV ...

Of course it runs NetBSD.

Binaries.

• Daily builds https://nycdn.netbsd.org/pub/NetBSD-daily/HEAD/latest/
• Releases https://cdn.netbsd.org/pub/NetBSD/

Community support.

• Bugs and patches can be sent via Gnats https://www.netbsd.org/cgi-bin/sendpr.cgi?gndb=netbsd.
• Several mailing lists https://www.netbsd.org/mailinglists exist. The netbsd-users list is a good choice for many problems.
• A community IRC channel exist on #netbsd @ freenode
• Twitter, GitHub, etc...

Who uses NetBSD?

• Commercial vendors
• Researchers
• Hobbyists

For additional introduction check The NetBSD Guide.

https://www.netbsd.org/docs/guide/en/

NetBSD participated successfully in the following Google's Summer of Code programs:

• 2005-2013

and

• 2016-2019.

In 2019 there were 7 succesful projects for The NetBSD Foundation.

Check https://blog.netbsd.org/ for their reports.

I've mentored 2 students this year.

• Siddharth Muralee (India) "Kernel fuzzing with syzkaller"
• Akul Pillai (India) "Kernel fuzzing with TriforceAFL"

Syzkaller + syzbot 24/7 fuzzing with KCOV assisted coverage driver

http://blog.netbsd.org/tnf/entry/enhancing_syzkaller_support_for_netbsd http://blog.netbsd.org/tnf/entry/enchancing_syzkaller_support_for_netbsd http://blog.netbsd.org/tnf/entry/enchancing_syzkaller_support_for_netbsd1

GSoC 2019 by Siddharth Muralee

http://blog.netbsd.org/tnf/entry/adapting_triforceafl_for_netbsd_part http://blog.netbsd.org/tnf/entry/adapting_triforceafl_for_netbsd_part1 http://blog.netbsd.org/tnf/entry/adapting_triforceafl_for_netbsd_part2

GSoC 2019 by Akul Pillai

Prehistory

• [1965] Multics
• [1969] UNIX First Edition
• [1977] 1BSD
• [1993] BSD/386 1.0
• [1993] NetBSD 0.8
• [1994] NetBSD 1.0
• [1995] 4.4BSD Lite Release 2
• [1995] NetBSD 1.1

-- /usr/share/misc/bsd-family-tree

Modern times

• [2009] NetBSD 5.0
• [2012] NetBSD 6.0
• [2015] NetBSD 7.0
• [2018] NetBSD 8.0
• [2019] NetBSD 8.1

-- /usr/share/misc/bsd-family-tree

• Released July 17 2018

https://www.netbsd.org/releases/formal-8/NetBSD-8.0.html

• 1410 resolved pullups to netbsd-8 as of Oct 18th 2019

http://releng.netbsd.org/cgi-bin/req-8.cgi

NetBSD 9.0 release process has started on July 31st 2019

• 350 resolved pullups to netbsd-9 as of Oct 18th 2019

http://releng.netbsd.org/cgi-bin/req-9.cgi

The NetBSD Foundation hires now a release engineering developer (martin@).

New AArch64 (ARM64) architecture support:

• Symmetric and asymmetrical multiprocessing support (aka big.LITTLE)
• Support for running 32-bit binaries
• UEFI and ACPI support
• Support for SBSA/SBBR (server-class) hardware.

The FDT-ization of many ARM boards:

• the 32-bit GENERIC kernel lists 129 different DTS configurations
• the 64-bit GENERIC64 kernel lists 74 different DTS configurations
• All supported by a single kernel, without requiring per-board configurations.

Selection of new boards:

• Olimex A10-OLinuXino-LIME
• Olimex A13-OLinuXino/-MICRO
• C.H.I.P./Pro/Pocket
• Pine64 / PineBook / Its / Sophine / Rock64 / ROCKPro64
• FriendlyARM NanoPi NEO2 / NEO Pluse2
• Orange Pi One Plus, Pine H64
• SoftIron Overdrive 1000
• nvidia TXI
• ODROID-XU3/XU4
• Exynos 5422
• many others....

RISCV getting closer, boots in emulator.

Still no real hardware support.

New device drivers for various devices on older hardware, such as:

• cpuctl for NetBSD/sparc and NetBSD/sparc64,
• Milan for NetBSD/atari,
• better Mac G5 NetBSD/macppc support,
• VAXstation 4000 TURBOchannel support

Oldschool NetBSD/Xen is still maintained.

NetBSD was the first Operating System shipping with Xen support.

New approached with kernel backends (Linux KVM-style) for qemu-alike frontend:

• NVMM (Intel and AMD x86_64)
• HAXM (Intel x86_64 and potentially i386)

WoW (Wine32 + Wine64) improvements.

Sanitizer is a programming tool that detects computer program bugs such as:

• buffer overflows,
• signed integer overflow,
• uninitialized memory read,
• data races etc.

The fundamental five types of sanitizers:

• Address Sanitizer (Asan) - Finds invalid address usage bugs.
• Undefined Behavior Sanitizer (UBSan) - Finds unspecified code semantics bugs.
• Thread Sanitizer (TSan) - Finds threading bugs.
• Memory Sanitizer (MSan) - Finds uninitialized memory read.
• Leak Sanitizer (LSan) - Finds memory leaks.

Additionally:

• libFuzzer - Library fuzzer
• SafeStack - Stack hardening
• XRay - Function call tracer

All of them main five userland sanitizers are supported on NetBSD.

• ASan (amd64, i386, other ports in various degree)
• UBSan (all ports)
• MSan (amd64)
• TSan (amd64)
• LSan (amd64, i386, other ports in various degree)

NetBSD pass 95% of the upstream LLVM tests.

There are sanitizers available in the NetBSD kernel.

• kASan (amd64, aarch64)
• kUBSan (all ports)
• kMSan (amd64 - finished, still not merged, waiting for LLVM upgrade)
• kTSan is WIP
• KLEAK (amd64)

MKSANITIZER is a distinct feature of NetBSD that allows the whole distribution sanitization.

Kernel correctness and completeness of features in ptrace(2) is highly improved for debuggers (lldb, gdb), syscall tracers (strace-like) and sanitizers (lsan).

The LLVM LLDB support is getting closer to being accomplished and fully featured.

GNU GDB support is improving (gdbserver is now available, many bugs are gone).

• LGTM bot

• Intel CPU bugs mitigation
• Kernel ASLR

Graphics driver update, matching Linux 4.4, adding support for up to Kaby Lake based Intel graphics devices.

Mesa was updated to 18.3.4, and llvmpipe is now available for several architectures, providing 3D graphics even in the absence of a supported GPU.

ZFS has been updated to a modern version and seen many bugfixes.

Further SMP-ification of the codebase.

NPF is now the recommended packet filter for new users and IPF/PF are deprecated.

NPF performance improvements and bug fixes. A new lookup algorithm, thmap, is now the default

The NetBSD Foundation funded project to port FreeBSD wifi stack (not merged yet).

• Upgrades to GCC 7.x, LLVM 7.x
• Native Command Queuing (NCQ) support
• Installer improvements (GPT, UEFI)
• Performance Metric Counters (PMC) for amd64 and aarch64
• Modularization of compat modules
• DTrace update and bugfixes
• new syscall tracers (picotrace, NetBSD truss, singlestepper)
• ...

• NetBSD/acorn26
• ipkgdb - IP-based kernel debugger
• vm86
• isdn4bsd
• NDIS wraper
• EtherIP - Ethernet over IP
• ...