Re: [PATCH] kexec_buffer measure

From: Tetsuo Handa
Date: Thu May 02 2019 - 20:54:30 EST

On 2019/05/03 1:28, Casey Schaufler wrote:
> On 5/2/2019 8:48 AM, Mimi Zohar wrote:
>> [Cc'ing Paul, John, Casey]
>> On Mon, 2019-04-22 at 20:18 -0400, Mimi Zohar wrote:
>>> [Cc'ing LSM mailing list]
>>> On Fri, 2019-04-19 at 17:30 -0700, prakhar srivastava wrote:
>>>> 2) Adding a LSM hook
>>>> We are doing both the command line and kernel version measurement in IMA.
>>>> Can you please elaborate on how this can be used outside of the scenario?
>>>> That will help me come back with a better design and code. I am
>>>> neutral about this.
>>> As I said previously, initially you might want to only measure the
>>> kexec boot command line, but will you ever want to verify or audit log
>>> the boot command line hash? Perhaps LSMs would be interested in the
>>> boot command line. Should this be an LSM hook?
>> From an LSM perspective, is there any interest in the boot command line?
> I can imagine an LSM that cares about the command line,
> but I don't have interest in it for any work I have in progress.

Since the kernel command line controls which LSMs to enable, I doubt that
an LSM which cares about the command line can detect that the kernel command
line was tampered when the kernel command line was tampered...