Re: [RFC PATCH v3 05/12] fs: add security blob and hooks for block_device

[Casey Schaufler]

On 4/22/2020 9:42 AM, James Morris wrote:
> On Wed, 15 Apr 2020, deven.desai@xxxxxxxxxxxxxxxxxxx wrote:
>
>> From: Deven Bowers <deven.desai@xxxxxxxxxxxxxxxxxxx>
>>
>> Add a security blob and associated allocation, deallocation and set hooks
>> for a block_device structure.
>>
>> Signed-off-by: Deven Bowers <deven.desai@xxxxxxxxxxxxxxxxxxx>
> Is there any feedback from block or LSM folk on the addition of a security 
> blob for block_device here?

The addition of a blob looks to have been done correctly.
As for it's use, I haven't had the chance to review the patches that
use it. I didn't see a patch that implements the hooks in a LSM,
but that could just be me. 

>
> IPE uses this is to track the status of integrity verification of e.g. 
> DM-Verity devices, per this code from a subsequent patch:
>
>
> +       ret = security_bdev_setsecurity(dm_table_get_md(v->ti->table)->bdev,
> +                                       DM_VERITY_SIGNATURE_SEC_NAME,
> +                                       v->sig->sig, v->sig->sig_size);
>
>