Re: [edk2-devel] [edk2-discuss] GSoC Proposal


Pedro Falcato <pedro.falcato@...>
 

Hi Marvin, Ada,

Some comments:

I don't think the purpose of the dynamic linker is to treat EFI as a complete operating system, but to try to eliminate the static linking that may be needlessly duplicating
code that could instead be put in a single dynamic library. For instance, MdePkg and MdeModulePkg are linked into a *lot* of .efi, instead of being just a library. It'd be nice to see some
numbers on this (something like Google's bloaty could be run on every .efi file, in order to understand how much file space we would actually save).

Other comments inline.

On Wed, Apr 13, 2022 at 4:15 PM Marvin Häuser <mhaeuser@...> wrote:

On 13. Apr 2022, at 16:38, Ada Christine <adachristine18@...> wrote:

i was replying via the groups.io web interface, I'm guessing that messed up
the thread? i haven't used mailing lists before and don't know how they
work. I'll use my mail client from here on.

I'm on board with not treating EFI as an operating system. the more i think
about it the more it looks like scope creep.

Agreed.

I'm not quite as enthusiastic
about it as i was at first glance.

I'm still keen on doing my gsoc proposal for edk, though, and even if this
task and the acpica application are decided to be out of scope unit
testing,

How about fuzz-testing? This is also something edk2 needs quite badly. At Acidanthera, we compile edk2 code in userspace outside the edk2 build system and fuzz with dummy applications.

Note: fuzzing is also part of the LLVM instrumentation suite (see https://llvm.org/docs/LibFuzzer.html) and is something I could happily mentor.
clang integration

Pedro and Vitaly are looking for someone to finish ASan: https://edk2.groups.io/g/devel/topic/90010978#87991
There are working UBSan concepts, but they also need to be mainlined.

Is Vitaly going to be a mentor? I was assuming it was going to be me and some other, more senior, mentor (possibly Steven Shi, which I included in the task).
Anyway, re: ASAN, if the project includes ASAN, UBSAN and possibly some other sanitizer it's quite possible that it could be considered a large project (which means more hours but a larger stipend too). Fuzzing + coverage could
be very nice additions to this project idea.
Also, is stress-testing a decent idea?

and source-level debugging are all relevant to
my interests.

how about your ideas for security stuff?

I want the entirety of MM to leverage SmmMemLib and to support SMAP. SmmMemLib would then handle UEFI->MMRAM and BaseMemoryLib would only work on MMRAM. Also evaluation of how to best avoid pointers in MM communication buffers would be nice.

There also is a bunch of other stuff, like working out moving a part of CpuDxe into DxeCore to have memory protection live immediately, memory protection in PEI, a replacement for the TE format (it’s buggy and most platforms mostly abandoned it over various issues), and alternatives to guarding critical code with SMM (like allowing NVRAM commits only as part of a reboot).

I personally find all of those projects very important, but I cannot promise many people agree. Especially those that impose global changes (most notably the TE replacement) may be very tedious to submit. Gladly, I believe you can submit multiple proposals (?)

Best regards,
Marvin

I'm not very knowledgeable about
trusted platform or secure boot but I'm willing to learn whatever is
necessary to get something spun up for my proposal.

On Wed, Apr 13, 2022, 12:05 Marvin Häuser <mhaeuser@...> wrote:

Do you use the “reply all” option in your mail client? Looks like my CCs
have been dropped again. Comments inline.

On 13. Apr 2022, at 12:54, Ada Christine <adachristine18@...>
wrote:
Hi, Marvin

Its similarity to my own latest experiment is the key to what grabbed my
attention. I have no particular use case in mind for it, but I see its
potential for anybody developing larger applications in that when a library
is changed there's no need to distribute a new version of the whole binary,
just the relevant library module.

I really do not like the trend of treating UEFI as a full-fledged OS - it
is not. The most used UEFI applications, OS loaders, are really not that
huge and are distributed as part of the OS image anyway. Even for less used
applications, you will always get a full snapshot anyhow. Gladly we don’t
have auto-update and package management yet. :)


I slept on it and it occurred to me that the whole thing could operate
similarly to the shell protocol in that the linker/loader is itself an
application that does a LoadImage() on the application needing dynamic
linking facilities.

That would mean the linker itself is shipped with every application that
requires it? Otherwise it doesn’t make much sense for it to be an app and
below’s problems apply.

If however the whole plan is making the linker as a DXE and including it
with the firmware, that I'm not quite as sure about. That would necessarily
tie any applications using dynamic linking to TianoCore or any firmware
distribution that derives from it.

I think that was the idea referred to as “edk2 core” by Steven, but I’d
like to hear his proposal to be sure. Virtually everyone uses edk2, so that
itself is not the problem, but versioning is. Vendors are slow to update
their snapshots or have just given up doing that entirely. Distributing it
for external applications like OS loaders would mean this can be leveraged
probably no earlier than 10 years from now. And for in-firmware things, I
have a hard time thinking about a use-case that outweighs the drawbacks.


To shift the topic slightly back to GSoC, however, I'm willing to work
on other items on the task list. Unit testing and an ACPICA application are
the alternative projects I had thought about. I need to choose fairly soon
as the proposal deadline is next Tuesday. I know a tiny bit about porting
ACPICA as I also have plans to incorporate it into my own project.

I have a few more ideas for security stuff, but Nate did not confirm them
as appropriate yet and I’m not here to drive you away from this specific
task (or the others). However, I’m still curious and concerned. :)

Best regards,
Marvin








--
Pedro Falcato

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