[PATCH v2] lsm: adds process attribute getter for Landlock

[Casey Schaufler]

On 5/22/2023 11:13 PM, Jeff Xu wrote:
> On Mon, May 22, 2023 at 12:56 PM Paul Moore <paul at paul-moore.com> wrote:
>> On Thu, May 18, 2023 at 5:26 PM Casey Schaufler <casey at schaufler-ca.com> wrote:
>>> On 5/18/2023 1:45 PM, Shervin Oloumi wrote:
>>>> Adds a new getprocattr hook function to the Landlock LSM, which tracks
>>>> the landlocked state of the process. This is invoked when user-space
>>>> reads /proc/[pid]/attr/domain
>>> Please don't add a Landlock specific entry directly in the attr/
>>> directory. Add it only to attr/landlock.
>>>
>>> Also be aware that the LSM maintainer (Paul Moore) wants to move
>>> away from the /proc/.../attr interfaces in favor of a new system call,
>>> which is in review.
>> What Casey said above.
>>
>> There is still some uncertainty around timing, and if we're perfectly
>> honest, acceptance of the new syscalls at the Linus level, but yes, I
>> would very much like to see the LSM infrastructure move away from
>> procfs and towards a syscall API.  Part of the reasoning is that the
>> current procfs API is ill-suited to handle the multiple, stacked LSMs
>> and the other part being the complexity of procfs in a namespaced
>> system.  If the syscall API is ultimately rejected, we will need to
>> revisit the idea of a procfs API, but even then I think we'll need to
>> make some changes to the current approach.
>>
>> As I believe we are in the latter stages of review for the syscall
>> API, perhaps you could take a look and ensure that the current
>> proposed API works for what you are envisioning with Landlock?
>>
> Which review/patch to look for the proposed API ?

https://lore.kernel.org/lkml/20230428203417.159874-3-casey@schaufler-ca.com/T/


> I guess ChromeOS will need to backport to 5.10 when the proposal is accepted.
>
> Thanks
> -Jeff
>
>
>> --
>> paul-moore.com