Re: [PATCH v38 06/39] LSM: lsm_self_attr syscall for LSM self attributes

From: Casey Schaufler
Date: Thu Oct 20 2022 - 12:13:46 EST


On 10/20/2022 8:44 AM, Paul Moore wrote:
> On Tue, Sep 27, 2022 at 3:57 PM Casey Schaufler <casey@xxxxxxxxxxxxxxxx> wrote:
>> Create a system call lsm_self_attr() to provide the security
>> module maintained attributes of the current process. Historically
>> these attributes have been exposed to user space via entries in
>> procfs under /proc/self/attr.
> Hi Casey,
>
> I had hoped to get to review these patches earlier this week, I know
> you are very anxious to see something happen here, but unfortunately
> that didn't work out and I'm now in a position of limited network
> access and time for a bit. I will do my best to at least comment on
> the new syscall related additions, but thankfully you've already
> started to get some good comments from others so I'm hopeful that will
> help you keep moving forward.

Thanks. I just got back to work myself. Hopefully the comments will prove
useful. I'm just getting to them.

> One comment I did want to make, and it's important: please separate
> the LSM syscall patches from the LSM stacking patches. While the
> stacking patches will obviously be dependent on the syscall patches,
> the syscall patches should not be dependent on stacking. However, the
> LSM syscall patches must be designed from the start to support
> multiple, simultaneous LSMs.

OK. I will refactor into two patch sets. The first will be the syscalls
for getting the LSM attributes and the second will be the stacking changes.
The prctl() I proposed to set the "display" LSM will be in the second, as
it makes no sense to have without anything to change. I have not to date
included the SO_PEERCONTEXT that would be required for complete stacking.
Would you like to see that included in the syscall patches?


> Thanks.

Thank you.