Re: [PATCH v3 1/8] tpm: Initialize crypto_id of allocated_banks to HASH_ALGO__LAST

[Jarkko Sakkinen]

On Mon, Feb 10, 2020 at 11:00:41AM +0100, Roberto Sassu wrote:
> chip->allocated_banks, an array of tpm_bank_info structures, contains the
> list of TPM algorithm IDs of allocated PCR banks. It also contains the
> corresponding ID of the crypto subsystem, so that users of the TPM driver
> can calculate a digest for a PCR extend operation.
> 
> However, if there is no mapping between TPM algorithm ID and crypto ID, the
> crypto_id field of tpm_bank_info remains set to zero (the array is
> allocated and initialized with kcalloc() in tpm2_get_pcr_allocation()).
> Zero should not be used as value for unknown mappings, as it is a valid
> crypto ID (HASH_ALGO_MD4).
> 
> Thus, initialize crypto_id to HASH_ALGO__LAST.
> 
> Cc: stable@xxxxxxxxxxxxxxx # 5.1.x
> Fixes: 879b589210a9 ("tpm: retrieve digest size of unknown algorithms with PCR read")
> Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
> Reviewed-by: Petr Vorel <pvorel@xxxxxxx>

Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>

/Jarkko