On February 12th, 2015, the DMTF released version 3.0.0 of the System Management BIOS Reference Specification. This update isn't just adding enumerated values to existing structures, as previous updates did. It is also introducing a new entry point format which allows for larger tables and structures. Support for this needs to be added to dmidecode.

Additionally, reading the entry point and the table from /dev/mem is no longer possible on all systems, so some work is in progress to offer an alternative interface through sysfs. It would be great to finalize this and release a new version of dmidecode that would support both SMBIOS version 3.0 and this new kernel interface.

Looking for hackers with the skills:

smbios dmi kernel c

This project is part of:

Hack Week 12

Activity

  • over 5 years ago: dawei_pang liked this project.
  • over 9 years ago: royfranz joined this project.
  • over 9 years ago: joeyli liked this project.
  • over 9 years ago: jdelvare added keyword "c" to this project.
  • over 9 years ago: jdelvare added keyword "smbios" to this project.
  • over 9 years ago: jdelvare added keyword "dmi" to this project.
  • over 9 years ago: jdelvare added keyword "kernel" to this project.
  • over 9 years ago: jdelvare started this project.
  • over 9 years ago: jdelvare originated this project.

  • Comments

    • jdelvare
      over 9 years ago by jdelvare | Reply

      Roy Franz's patches have been reviewed, tested and committed. This lets dmidecode make use of the upcoming sysfs interface to DMI tables.

    • jdelvare
      over 9 years ago by jdelvare | Reply

      I have just committed the dmidecode patches that implement support for the SMBIOS 3.0.0 specification. So the user-space side of the project is mostly completed, although a few cleanups and improvements are still possible.

    • jdelvare
      over 9 years ago by jdelvare | Reply

      I committed a few more patches yesterday and this morning. There's one issue left that I'm aware of (reading SMBIOS 3.0 64-table from a dump file), I'll look into it.

    • jdelvare
      over 9 years ago by jdelvare | Reply

      A kernel fix was merged upstream:
      http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5c1ac56b51b9d222ab202dec1ac2f4215346129d

      The remaining 8 kernel patches are queued for kernel v4.2:
      http://jdelvare.nerim.net/devel/linux/jdelvare-dmi/

    Similar Projects

    Linux on Cavium CN23XX cards by tsbogend

    Before Cavium switched to ARM64 CPUs they developed quite powerful MIPS based SOCs. The current upstream Linux kernel already supports some Octeon SOCs, but not the latest versions. Goal of this Hack Week project is to use the latest Cavium SDK to update the Linux kernel code to let it running on CN23XX network cards.


    Hacking on sched_ext by flonnegren

    Description

    Sched_ext upstream has some interesting issues open for grabs:

    Goals

    Send patches to sched_ext upstream

    Also set up perfetto to trace some of the example schedulers.

    Resources

    https://github.com/sched-ext/scx


    Contributing to Linux Kernel security by pperego

    Description

    A couple of weeks ago, I found this blog post by Gustavo Silva, a Linux Kernel contributor.

    I always strived to start again into hacking the Linux Kernel, so I asked Coverity scan dashboard access and I want to contribute to Linux Kernel by fixing some minor issues.

    I want also to create a Linux Kernel fuzzing lab using qemu and syzkaller

    Goals

    1. Fix at least 2 security bugs
    2. Create the fuzzing lab and having it running

    The story so far

    • Day 1: setting up a virtual machine for kernel development using Tumbleweed. Reading a lot of documentation, taking confidence with Coverity dashboard and with procedures to submit a kernel patch
    • Day 2: I read really a lot of documentation and I triaged some findings on Coverity SAST dashboard. I have to confirm that SAST tool are great false positives generator, even for low hanging fruits.
    • Day 3: Working on trivial changes after I read this blog post: https://www.toblux.com/posts/2024/02/linux-kernel-patches.html. I have to take confidence with the patch preparation and submit process yet.
      • First trivial patch sent: using strtruefalse() macro instead of hard-coded strings in a staging driver for a lcd display
      • Fix for a dereference before null check issue discovered by Coverity (CID 1601566) https://scan7.scan.coverity.com/#/project-view/52110/11354?selectedIssue=1601566
    • Day 4: Triaging more issues found by Coverity.
      • The patch for CID 1601566 was refused. The check against the NULL pointer was pointless so I prepared a version 2 of the patch removing the check.
      • Fixed another dereference before NULL check in iwlmvmparsewowlaninfo_notif() routine (CID 1601547). This one was already submitted by another kernel hacker :(
    • Day 5: Wrapping up. I had to do some minor rework on patch for CID 1601566. I found a stalker bothering me in private emails and people I interacted with me, advised he is a well known bothering person. Markus Elfring for the record.
    • Wrapping up: being back doing kernel hacking is amazing and I don't want to stop it. My battery pack is completely drained but changing the scope gave me a great twist and I really want to feel this energy not doing a single task for months.

      I failed in setting up a fuzzing lab but I was too optimistic for the patch submission process.

    The patches

    1


    Officially Become a Kernel Hacker! by m.crivellari

    Description

    My studies as well my spare time are dedicated to the Linux Kernel. Currently I'm focusing on interrupts on x86_64, but my interests are not restricted to one specific topic, for now.

    I also "played" a little bit with kernel modules (ie lantern, a toy packet analyzer) and I've added a new syscall in order read from a task A, the memory of a task B.

    Maybe this will be a good chance to...

    Goals

    • create my first kernel patch

    Resources

    Achivements


    early stage kdump support by mbrugger

    Project Description

    When we experience a early boot crash, we are not able to analyze the kernel dump, as user-space wasn't able to load the crash system. The idea is to make the crash system compiled into the host kernel (think of initramfs) so that we can create a kernel dump really early in the boot process.

    Goal for the Hackweeks

    1. Investigate if this is possible and the implications it would have (done in HW21)
    2. Hack up a PoC (done in HW22 and HW23)
    3. Prepare RFC series (giving it's only one week, we are entering wishful thinking territory here).

    update HW23

    • I was able to include the crash kernel into the kernel Image.
    • I'll need to find a way to load that from init/main.c:start_kernel() probably after kcsan_init()
    • I workaround for a smoke test was to hack kexec_file_load() systemcall which has two problems:
      1. My initramfs in the porduction kernel does not have a new enough kexec version, that's not a blocker but where the week ended
      2. As the crash kernel is part of init.data it will be already stale once I can call kexec_file_load() from user-space.

    The solution is probably to rewrite the POC so that the invocation can be done from init.text (that's my theory) but I'm not sure if I can reuse the kexec infrastructure in the kernel from there, which I rely on heavily.

    update HW24

    • Day1
      • rebased on v6.12 with no problems others then me breaking the config
      • setting up a new compilation and qemu/virtme env
      • getting desperate as nothing works that used to work
    • Day 2
      • getting to call the invocation of loading the early kernel from __init after kcsan_init()
    • Day 3

      • fix problem of memdup not being able to alloc so much memory... use 64K page sizes for now
      • code refactoring
      • I'm now able to load the crash kernel
      • When using virtme I can boot into the crash kernel, also it doesn't boot completely (major milestone!), crash in elfcorehdr_read_notes()
    • Day 4

      • crash systems crashes (no pun intended) in copy_old_mempage() link; will need to understand elfcorehdr...
      • call path vmcore_init() -> parse_crash_elf_headers() -> elfcorehdr_read() -> read_from_oldmem() -> copy_oldmem_page() -> copy_to_iter()
    • Day 5

      • hacking arch/arm64/kernel/crash_dump.c:copy_old_mempage() to see if crash system really starts. It does.
      • fun fact: retested with more reserved memory and with UEFI FW, host kernel crashes in init but directly starts the crash kernel, so it works (somehow) \o/
    • TODOs

      • fix elfcorehdr so that we actually can make use of all this...
      • test where in the boot __init() chain we can/should call kexec_early_dump()


    Add a machine-readable output to dmidecode by jdelvare

    Description

    There have been repeated requests for a machine-friendly dmidecode output over the last decade. During Hack Week 19, 5 years ago, I prepared the code to support alternative output formats, but didn't have the time to go further. Last year, Jiri Hnidek from Red Hat Linux posted a proof-of-concept implementation to add JSON output support. This is a fairly large pull request which needs to be carefully reviewed and tested.

    Goals

    Review Jiri's work and provide constructive feedback. Merge the code if acceptable. Evaluate the costs and benefits of using a library such as json-c.


    FastFileCheck work by pstivanin

    Description

    FastFileCheck is a high-performance, multithreaded file integrity checker for Linux. Designed for speed and efficiency, it utilizes parallel processing and a lightweight database to quickly hash and verify large volumes of files, ensuring their integrity over time.

    https://github.com/paolostivanin/FastFileCheck

    Goals

    • Release v1.0.0

    Design overwiew:

    • Main thread (producer): traverses directories and feeds the queue (one thread is more than enough for most use cases)
    • Dedicated consumer thread: manages queue and distributes work to threadpool
    • Worker threads: compute hashes in parallel

    This separation of concerns is efficient because:

    • Directory traversal is I/O bound and works well in a single thread
    • Queue management is centralized, preventing race conditions
    • Hash computation is CPU-intensive and properly parallelized


    ESETv2 Emulator / interpreter by m.crivellari

    Description

    ESETv2 is an intriguing challenge developed by ESET, available on their website under the "Challenge" menu. The challenge involves an "assembly-like" language and a Python compiler that generates .evm binary files.

    This is an example using one of their samples (it prints N Fibonacci numbers):

    .dataSize 0
    .code
    
    loadConst 0, r1 # first
    loadConst 1, r2 # second
    
    loadConst 1, r14 # loop helper
    
    consoleRead r3
    
    loop:
        jumpEqual end, r3, r15
    
        add r1, r2, r4
        mov r2, r1
        mov r4, r2
    
        consoleWrite r1
    
        sub r3, r14, r3
        jump loop
    end:
    hlt
    

    This language also supports multi-threading. It includes instructions such as createThread to start a new thread, joinThread to wait until a thread completes, and lock/unlock to facilitate synchronization between threads.

    Goals

    • create a full interpreter able to run all the available samples provided by ESET.
    • improve / optimize memory (eg. using bitfields where needed as well as avoid unnecessary memory allocations)

    Resources

    Achivements

    Project still not complete. Added lock / unlock instruction implementation but further debug is needed; there is a bug somewhere. Actually the code it works for almost all the examples in the samples folder. 1 of them is not yet runnable (due to a missing "write" opcode implementation), another will cause the bug to show up; still not investigated, anyhow.


    FizzBuzz OS by mssola

    Project Description

    FizzBuzz OS (or just fbos) is an idea I've had in order to better grasp the fundamentals of the low level of a RISC-V machine. In practice, I'd like to build a small Operating System kernel that is able to launch three processes: one that simply prints "Fizz", another that prints "Buzz", and the third which prints "FizzBuzz". These processes are unaware of each other and it's up to the kernel to schedule them by using the timer interrupts as given on openSBI (fizz on % 3 seconds, buzz on % 5 seconds, and fizzbuzz on % 15 seconds).

    This kernel provides just one system call, write, which allows any program to pass the string to be written into stdout.

    This project is free software and you can find it here.

    Goal for this Hackweek

    • Better understand the RISC-V SBI interface.
    • Better understand RISC-V in privileged mode.
    • Have fun.

    Resources

    Results

    The project was a resounding success add-emoji Lots of learning, and the initial target was met.