Re: [PATCH] bpf: validate bpf_func when BPF_JIT is enabled

From: Toke HÃiland-JÃrgensen
Date: Fri Sep 13 2019 - 08:19:41 EST


Sami Tolvanen <samitolvanen@xxxxxxxxxx> writes:

> On Thu, Sep 12, 2019 at 3:52 AM Toke HÃiland-JÃrgensen <toke@xxxxxxxxxx> wrote:
>> I think it would be good if you do both. I'm a bit worried that XDP
>> performance will end up in a "death by a thousand paper cuts" situation,
>> so I'd rather push back on even relatively small overheads like this; so
>> being able to turn it off in the config would be good.
>
> OK, thanks for the feedback. In that case, I think it's probably
> better to wait until we have CFI ready for upstreaming and use the
> same config for this one.

SGTM, thanks!

>> Can you share more details about what the "future CFI checking" is
>> likely to look like?
>
> Sure, I posted an overview of CFI and what we're doing in Pixel devices here:
>
> https://android-developers.googleblog.com/2018/10/control-flow-integrity-in-android-kernel.html

Great, thank you.

-Toke