[U-Boot] [PATCH 2/2] usbarmory: Add board_run_command() function

[Simon Glass]

Hi,

On 27 June 2016 at 03:38, Stefano Babic <sbabic at denx.de> wrote:
> Hi Andrej,
>
> On 20/06/2016 18:18, Andrej Rosano wrote:
>
>>>
>>> I ten to NACK this. You can do exactly the same with a U-Boot script,
>>> and if you want to have this as default, you can change your default
>>> environment. This is just a wrapper around the hush shell.
>>
>> The intention of the patch is to boot the kernel while having the CLI disabled
>> (CONFIG_CMDLINE=n). The U-Boot script needs the CLI to be enabled AFAIK.
>>
>> It is better having the CLI disabled when using the Verified Boot, otherwise
>> there are chances to bypass the FIT image verification (e.g. using md/mw
>> commands in case are available):
>
> Why is it not enough to disable the CONSOLE ? I mean, if there is no
> user interface (and this is done in a lot of ways, for example setting
> stdin / stdout), there is no ways to bypass it because the interface is
> not availabel. Or is there some other security issues I am not aware of ?

It is an extra level of security - providing a very simple command
execution instead of the general CLI. That is actually the original
purpose of board_run_command(). E.g. for Chrome OS we had an option to
either run the normal CLI or a simple (secure) one. Also see
cli_process_fdt() which provides for a 'bootsecure' mode, controlled
from the FDT.

Regards,
Simon