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.

Fixes: 879b589210a9 ("tpm: retrieve digest size of unknown algorithms with PCR read") Signed-off-by: Roberto Sassu roberto.sassu@huawei.com Reviewed-by: Petr Vorel pvorel@suse.cz Cc: stable@vger.kernel.org --- drivers/char/tpm/tpm2-cmd.c | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 13696deceae8..760329598b99 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -525,6 +525,8 @@ static int tpm2_init_bank_info(struct tpm_chip *chip, u32 bank_index) return 0; }

+ bank->crypto_id = HASH_ALGO__LAST; + return tpm2_pcr_read(chip, 0, &digest, &bank->digest_size); }