Re: [PATCH] block: Check ADMIN before NICE for IOPRIO_CLASS_RT

From: Jens Axboe
Date: Mon Nov 15 2021 - 20:22:58 EST


On 11/15/21 10:38 AM, Alistair Delva wrote:
> Booting to Android userspace on 5.14 or newer triggers the following
> SELinux denial:
>
> avc: denied { sys_nice } for comm="init" capability=23
> scontext=u:r:init:s0 tcontext=u:r:init:s0 tclass=capability
> permissive=0
>
> Init is PID 0 running as root, so it already has CAP_SYS_ADMIN. For
> better compatibility with older SEPolicy, check ADMIN before NICE.

Seems a bit wonky to me, but the end result is the same. In any case,
this warrants a comment above it detailing why the ordering is
seemingly important.

--
Jens Axboe