Re: [dm-devel] [PATCH] dm: remake of the verity target

[Mandeep Singh Baines <msb chromium org>]

On Tue, Mar 20, 2012 at 8:44 PM, Mikulas Patocka <mpatocka redhat com> wrote:
>
>
> On Tue, 20 Mar 2012, Mandeep Singh Baines wrote:
>
>> But we are hashing fixed-sized blocks so there is no possibility of extension.
>
> If the first part of some block contains some security-sensitive data and
> the last part of the same block can be attacker-controlled, he can use the
> collision attack to change the security-sensitive data.
>
>> However, better safe than sorry. I guess we'll just have to deal with
>> backward incompatibility. So feel free to add my sign off to the new
>> patch also.
>>
>> Signed-off-by: Mandeep Singh Baines <msb chromium org>
>>
>> Regards,
>> Mandeep
>>
>> > Mikulas
>
> I can introduce a switch to make it accept the old format. Do you want to?
>

We can carry that as an out-of-tree patch until we migrate.

On the other hand, it might be nice to support prepend or append.

I don't too strong feelings but it might be nice to have
prepend/append flag. Would definitely make our life easier.

> Mikulas