Re: [RFC PATCH] seccomp: Add protection keys into seccomp_data

On Tue, Nov 15, 2022 at 5:16 AM Michael Sammler [off-list ref] wrote:

quoted

We're currently working on a feature in chromium that uses pkeys for
in-process isolation. Being able to use the pkey state in the seccomp
filter would be pretty useful for this. For example, it would allow
us to enforce that no code outside the isolated thread would ever
map/mprotect executable memory.
We can probably do something similar by adding instruction pointer
checks to the seccomp filter, but that feels quite hacky and this
feature would make a much nicer implementation.

Are there any plans to make a version 2 of this patch?

Thanks for your interest in this patch, but I am now working on other projects and currently don't plan to make a version 2 of this patch.

I'd be happy to take over writing a version 2 for this.

Kees and Dave, does this feature overall look good to you?

From the discussion, I think there are two proposed changes:
* use an architecture-generic interface as Ram Pai suggested (i.e. add
a read_pkey function)
* ensure to restore the pkru value or fetch it from the xsave buffer