On Mon, Jul 18, 2022 at 05:52:01PM -0400, Paul Moore wrote:
On Mon, Jul 18, 2022 at 1:12 PM Casey Schaufler <casey@xxxxxxxxxxxxxxxx> wrote:On 7/15/2022 8:33 PM, Paul Moore wrote: > On Fri, Jul 15, 2022 at 3:52 PM Paul Moore <paul@xxxxxxxxxxxxxx> wrote: >> On Fri, Jul 15, 2022 at 3:28 PM Jens Axboe <axboe@xxxxxxxxx> 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?
Earlier testing was done using fio. liburing tests need a formal review in list. Tree is here - https://github.com/ankit-sam/liburing/tree/uring-pt It adds new "test/io_uring_passthrough.t", which can be run this way: ./test/io_uring_passthrough.t /dev/ng0n1 Requires nvme device (/dev/ng0n1). And admin-access as well, as this is raw open. FWIW, each passthrough command (at nvme driver level) is also guarded by admin-access. Ankit (CCed) has the plans to post it (will keep you guys in loop) after bit more testing with 5.20 branch.
All I have at the moment is the audit-testsuite io_uring test (link below) which is lacking a test for the io_uring CMD command. I plan on adding that, but I haven't finished the SELinux patch yet. * https://protect2.fireeye.com/v1/url?k=9cb2caea-fd39dfd9-9cb341a5-000babff9bb7-e1f9086bae09b852&q=1&e=b1985274-4644-447d-be8c-16f520cadbd9&u=https%3A%2F%2Fgithub.com%2Flinux-audit%2Faudit-testsuite%2Ftree%2Fmain%2Ftests%2Fio_uring (Side note: there will be a SELinux io_uring test similar to the audit-testsuite test, but that effort was delayed due to lack of io_uring support in the Fedora policy for a while; it's working now, but the SELinux/SCTP issues have been stealing my time lately.)
