Re: [PATCH] tpm: Add module parameter for hwrng quality.

From: Jarkko Sakkinen
Date: Mon Jun 18 2018 - 14:07:23 EST


On Fri, Jun 08, 2018 at 02:54:38PM +0800, Louis Collard wrote:
> It is now possible for drivers to easily specify a hwrng quality, however
> most do not currently do this, and in cases where they do, it may be
> desirable to override the driver-specified value with a user-specified
> one. This patch adds a parameter to set or override the hwrng quality.
>
> Signed-off-by: Louis Collard <louiscollard@xxxxxxxxxxxx>
> ---
> drivers/char/tpm/tpm-chip.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> index 0a62c19937b6..4def49cfc634 100644
> --- a/drivers/char/tpm/tpm-chip.c
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -33,6 +33,11 @@
> DEFINE_IDR(dev_nums_idr);
> static DEFINE_MUTEX(idr_lock);
>
> +static short override_rng_quality = -1;
> +module_param(override_rng_quality, short, 0644);

Should this be 600 i.e. not to leak this information?

/Jarkko