Description
Improve UML handling of segmentation faults in kernel mode. Although such page faults are generally caused by a kernel bug, it is annoying if they cause an infinite loop, or panic the kernel. More importantly, a robust implementation allows to write KUnit tests for various guard pages, preventing potential kernel self-protection regressions.
Goals
Convert the UML page fault handler to use oops_* helpers, go through a few review rounds and finally get my patch series merged in 6.14.
Resources
Wrong initial attempt: https://lore.kernel.org/lkml/20231215121431.680-1-petrtesarik@huaweicloud.com/T/
Looking for hackers with the skills:
This project is part of:
Hack Week 24
Comments
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Modularization and Modernization of cifs.ko for Enhanced SMB Protocol Support by hcarvalho
Creator:
Enzo Matsumiya ematsumiya@suse.de @ SUSE Samba team
Members:
Henrique Carvalho henrique.carvalho@suse.com @ SUSE Samba team
Description
Split cifs.ko in 2 separate modules; one for SMB 1.0 and 2.0.x, and another for SMB 2.1, 3.0, and 3.1.1.
Goals
Primary
Start phasing out/deprecation of older SMB versions
Secondary
- Clean up of the code (with focus on the newer versions)
- Update cifs-utils
- Update documentation
- Improve backport workflow (see below)
Technical details
Ideas for the implementation.
- fs/smb/client/{old,new}.c to generate the respective modules
- Maybe don't create separate folders? (re-evaluate as things progresses!)
- Remove server->{ops,vals} if possible
- Clean up fs_context.* -- merge duplicate options into one, handle them in userspace utils
- Reduce code in smb2pdu.c -- tons of functions with very similar init/setup -> send/recv -> handle/free flow
- Restructure multichannel
- Treat initial connection as "channel 0" regardless of multichannel enabled/negotiated status, proceed with extra channels accordingly
- Extra channel just point to "channel 0" as the primary server, no need to allocate an extra TCPServerInfo for each one
- Authentication mechanisms
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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
- https://www.kernel.org/doc/html/latest/process/submitting-patches.html
- https://git-send-email.io/ (mentioned also in the kernel doc)
- https://javiercarrascocruz.github.io/kernel-contributor-1
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- found while working on a bug, this is the 1st patch: cifs: avoid deadlocks while updating iface [✅ has been merged]
Modernize ocfs2 by goldwynr
Ocfs2 has gone into a stage of neglect and disrepair. Modernize the code to generate enough interest.
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FizzBuzz OS by mssola
Project Description
FizzBuzz OS (or just fbos
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Goal for this Hackweek
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- Have fun.
Resources
Results
The project was a resounding success Lots of learning, and the initial target was met.
Model checking the BPF verifier by shunghsiyu
Project Description
BPF verifier plays a crucial role in securing the system (though less so now that unprivileged BPF is disabled by default in both upstream and SLES), and bugs in the verifier has lead to privilege escalation vulnerabilities in the past (e.g. CVE-2021-3490).
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For the solver I will be using the Z3 SMT solver to do the checking since it provide a Python binding that's relatively easy to use.
Goal for this Hackweek
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Resources
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- Has a section specifically on model checking
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- Sound, Precise, and Fast Abstract Interpretation with Tristate Numbers - existing work that use formal verification to prove that the multiplication helper used for value tracking work as intended
- [PATCH v5 net-next 00/12] bpf: rewrite value tracking in verifier - initial patch set that adds tristate number to the verifier