Re: [PATCH v10 5/8] rust: security: add abstraction for secctx

[Alice Ryhl <aliceryhl@google.com>]

On Sun, Sep 22, 2024 at 6:50 PM Casey Schaufler <casey@schaufler-ca.com> wrote:
>
> On 9/22/2024 8:08 AM, Alice Ryhl wrote:
> > On Mon, Sep 16, 2024 at 5:40 PM Casey Schaufler <casey@schaufler-ca.com> wrote:
> >> On 9/15/2024 2:07 PM, Alice Ryhl wrote:
> >>> On Sun, Sep 15, 2024 at 10:58 PM Kees Cook <kees@kernel.org> wrote:
> >>>> On Sun, Sep 15, 2024 at 02:31:31PM +0000, Alice Ryhl wrote:
> >>>>> Add an abstraction for viewing the string representation of a security
> >>>>> context.
> >>>> Hm, this may collide with "LSM: Move away from secids" is going to happen.
> >>>> https://lore.kernel.org/all/20240830003411.16818-1-casey@schaufler-ca.com/
> >>>>
> >>>> This series is not yet landed, but in the future, the API changes should
> >>>> be something like this, though the "lsmblob" name is likely to change to
> >>>> "lsmprop"?
> >>>> security_cred_getsecid()   -> security_cred_getlsmblob()
> >>>> security_secid_to_secctx() -> security_lsmblob_to_secctx()
> >> The referenced patch set does not change security_cred_getsecid()
> >> nor remove security_secid_to_secctx(). There remain networking interfaces
> >> that are unlikely to ever be allowed to move away from secids. It will
> >> be necessary to either retain some of the secid interfaces or introduce
> >> scaffolding around the lsm_prop structure.
> >>
> >> Binder is currently only supported in SELinux, so this isn't a real issue
> >> today. The BPF LSM could conceivably support binder, but only in cases where
> >> SELinux isn't enabled. Should there be additional LSMs that support binder
> >> the hooks would have to be changed to use lsm_prop interfaces, but I have
> >> not included that *yet*.
> >>
> >>> Thanks for the heads up. I'll make sure to look into how this
> >>> interacts with those changes.
> >> There will be a follow on patch set as well that replaces the LSMs use
> >> of string/length pairs with a structure. This becomes necessary in cases
> >> where more than one active LSM uses secids and security contexts. This
> >> will affect binder.
> > When are these things expected to land?
>
> I would like them to land in 6.14, but history would lead me to think
> it will be later than that. A lot will depend on how well the large set
> of LSM changes that went into 6.12 are received.
>
> >  If this patch series gets
> > merged in the same kernel cycle as those changes, it'll probably need
> > special handling.
>
> Yes, this is the fundamental downside of the tree merge development model.

Okay. I'm hoping to land this series in 6.13 so hopefully we won't
need to do anything special.

Alice