On Wed, Mar 02, 2022 at 12:13:55PM +0100, Roberto Sassu wrote:

Extend the interoperability with IMA, to give wider flexibility for the
implementation of integrity-focused LSMs based on eBPF.

Patch 1 fixes some style issues.

Patches 2-6 give the ability to eBPF-based LSMs to take advantage of the
measurement capability of IMA without needing to setup a policy in IMA
(those LSMs might implement the policy capability themselves).

Patches 7-9 allow eBPF-based LSMs to evaluate files read by the kernel.

Changelog

v2:
- Add better description to patch 1 (suggested by Shuah)
- Recalculate digest if it is not fresh (when IMA_COLLECTED flag not set)
- Move declaration of bpf_ima_file_hash() at the end (suggested by
  Yonghong)
- Add tests to check if the digest has been recalculated
- Add deny test for bpf_kernel_read_file()
- Add description to tests

v1:
- Modify ima_file_hash() only and allow the usage of the function with the
  modified behavior by eBPF-based LSMs through the new function
  bpf_ima_file_hash() (suggested by Mimi)
- Make bpf_lsm_kernel_read_file() sleepable so that bpf_ima_inode_hash()
  and bpf_ima_file_hash() can be called inside the implementation of
  eBPF-based LSMs for this hook

Roberto Sassu (9):
  ima: Fix documentation-related warnings in ima_main.c
  ima: Always return a file measurement in ima_file_hash()
  bpf-lsm: Introduce new helper bpf_ima_file_hash()
  selftests/bpf: Move sample generation code to ima_test_common()
  selftests/bpf: Add test for bpf_ima_file_hash()
  selftests/bpf: Check if the digest is refreshed after a file write
  bpf-lsm: Make bpf_lsm_kernel_read_file() as sleepable
  selftests/bpf: Add test for bpf_lsm_kernel_read_file()
  selftests/bpf: Check that bpf_kernel_read_file() denies reading IMA
    policy

We have to land this set through bpf-next.
Please get the Acks for patches 1 and 2, so we can proceed.