Re: [PATCH v5 1/5] tpm: Return on tpm2_create_null_primary() failure

[Stefan Berger <stefanb@linux.ibm.com>]

On 9/21/24 8:08 AM, Jarkko Sakkinen wrote:
> tpm2_sessions_init() does not ignores the result of

s/ignores/ignore

> tpm2_create_null_primary(). Address this by returning -ENODEV to the
> caller.

I am not sure why mapping all errors to -ENODEV resolves the fact that 
tpm2_sessions_init() does not ignore the result of 
tpm2_create_null_primary(). I think what you want is to return -ENODEV 
from tpm2_auto_startup.

> 
> Cc: stable@vger.kernel.org # v6.10+
> Fixes: d2add27cf2b8 ("tpm: Add NULL primary creation")
> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
> ---
> v5:
> - Do not print klog messages on error, as tpm2_save_context() already
>    takes care of this.
> v4:
> - Fixed up stable version.
> v3:
> - Handle TPM and POSIX error separately and return -ENODEV always back
>    to the caller.
> v2:
> - Refined the commit message.
> ---
>   drivers/char/tpm/tpm2-sessions.c | 5 +++--
>   1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
> index d3521aadd43e..0f09ac33ae99 100644
> --- a/drivers/char/tpm/tpm2-sessions.c
> +++ b/drivers/char/tpm/tpm2-sessions.c
> @@ -1338,7 +1338,8 @@ static int tpm2_create_null_primary(struct tpm_chip *chip)
>   		tpm2_flush_context(chip, null_key);
>   	}
>   
> -	return rc;
> +	/* Map all errors to -ENODEV: */
> +	return rc ? -ENODEV : rc;

return rc ? -ENODEV : 0;

>   }
>   
>   /**
> @@ -1354,7 +1355,7 @@ int tpm2_sessions_init(struct tpm_chip *chip)
>   
>   	rc = tpm2_create_null_primary(chip);
>   	if (rc)
> -		dev_err(&chip->dev, "TPM: security failed (NULL seed derivation): %d\n", rc);
> +		return rc;
>   
>   	chip->auth = kmalloc(sizeof(*chip->auth), GFP_KERNEL);
>   	if (!chip->auth)