Re: [PATCH security-next v3 00/29] LSM: Explict LSM ordering

From: John Johansen
Date: Sat Sep 29 2018 - 14:20:06 EST


On 09/29/2018 03:48 AM, Tetsuo Handa wrote:
> On 2018/09/29 5:01, Kees Cook wrote:
>> On Fri, Sep 28, 2018 at 8:55 AM, Casey Schaufler <casey@xxxxxxxxxxxxxxxx> wrote:
>>> On 9/24/2018 5:18 PM, Kees Cook wrote:
>>>> v3:
>>>> - add CONFIG_LSM_ENABLE and refactor resulting logic
>>>
>>> Kees, you can add my
>>>
>>> Reviewed-by:Casey Schaufler <casey@xxxxxxxxxxxxxxxx>
>>>
>>> for this entire patch set. Thank you for taking this on, it's
>>> a significant and important chunk of the LSM infrastructure
>>> update.
>>
>> Thanks!
>>
>> John, you'd looked at this a bit too -- do the results line up with
>> your expectations?
>>
>> Any thoughts from SELinux, TOMOYO, or IMA folks?
>
> I'm OK with this approach. Thank you.
>
>
>
> Just wondering what is "__lsm_name_##lsm" for...
>
> +#define DEFINE_LSM(lsm) \
> + static const char __lsm_name_##lsm[] __initconst \
> + __aligned(1) = #lsm; \
> + static struct lsm_info __lsm_##lsm \
> + __used __section(.lsm_info.init) \
> + __aligned(sizeof(unsigned long)) \
> + = { \
> + .name = __lsm_name_##lsm, \
> +
> +#define END_LSM }
>
> We could do something like below so that funny END_LSM is not required?
> I felt } like a typo error at the first glance. What we need is to
> gather into one section with appropriate alignment, isn't it?
>

well and Kees was trying to automagically set the name. This threw
me off too at first and I am still trying to figure out if I would
prefer something simpler, and more standard like below.

> #define LSM_INFO \
> static struct lsm_info __lsm_ \
> __used __section(.lsm_info.init) \
> __aligned(sizeof(unsigned long)) \
>
> LSM_INFO = {
> .name = "tomoyo",
> .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
> .init = tomoyo_init,
> };
>