[PATCH v2] lsm, io_uring: add LSM hooks for the new uring_cmd file op

[Casey Schaufler]

On 7/15/2022 8:33 PM, Paul Moore wrote:
> On Fri, Jul 15, 2022 at 3:52 PM Paul Moore <paul at paul-moore.com> wrote:
>> On Fri, Jul 15, 2022 at 3:28 PM Jens Axboe <axboe at kernel.dk> wrote:
>>> On 7/15/22 1:16 PM, Luis Chamberlain wrote:
>>>> io-uring cmd support was added through ee692a21e9bf ("fs,io_uring:
>>>> add infrastructure for uring-cmd"), this extended the struct
>>>> file_operations to allow a new command which each subsystem can use
>>>> to enable command passthrough. Add an LSM specific for the command
>>>> passthrough which enables LSMs to inspect the command details.
>>>>
>>>> This was discussed long ago without no clear pointer for something
>>>> conclusive, so this enables LSMs to at least reject this new file
>>>> operation.
>>> From an io_uring perspective, this looks fine to me. It may be easier if
>>> I take this through my tree due to the moving of the files, or the
>>> security side can do it but it'd have to then wait for merge window (and
>>> post io_uring branch merge) to do so. Just let me know. If done outside
>>> of my tree, feel free to add:
> I forgot to add this earlier ... let's see how the timing goes, I
> don't expect the LSM/Smack/SELinux bits to be ready and tested before
> the merge window opens so I'm guessing this will not be an issue in
> practice, but thanks for the heads-up.

I have a patch that may or may not be appropriate. I ran the
liburing tests without (additional) failures, but it looks like
there isn't anything there testing uring_cmd. Do you have a
test tucked away somewhere I can use?

Thanks.