Re: [PATCH] mm/mincore: allow for making sys_mincore() privileged

[Linus Torvalds]

On Wed, Jan 16, 2019 at 5:25 PM Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote:
>
> Something like CAP_DAC_READ_SEARCH might not be crazy.

I agree that it would work. In fact' it's what Jiri's patch basically
did. Except Jiri used CAP_SYS_ADMIN instead.

But that then basically limits it to root (or root-like with
capability masks), which is quite likely to not work in practice all
that well. That's why I wanted to find alternatives.

*Very* few people want to run their databases as root.

Jiri's original patch kind of acknowledged that by making the new test
be conditional, and off by default. So then it's a "only do this for
lockdown mode, because normal people won't find it acceptable".

And I'm not a huge fan of that approach. If you don't protect normal
people, then what's the point, really?

              Linus