4.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx> commit 7d761119a914ec0ac05ec2a5378d1f86e680967d upstream. The error code handling is broken as any error code that has the same bits set as TPM_RC_HASH passes. Implemented tpm2_rc_value() helper to parse the error value from FMT0 and FMT1 error codes so that these types of mistakes are prevented in the future. Fixes: 5ca4c20cfd37 ("keys, trusted: select hash algorithm for TPM2 chips") Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx> Reviewed-by: Jason Gunthorpe <jgunthorpe@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/char/tpm/tpm.h | 5 +++++ drivers/char/tpm/tpm2-cmd.c | 2 +- 2 files changed, 6 insertions(+), 1 deletion(-) --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -529,6 +529,11 @@ static inline void tpm_add_ppi(struct tp } #endif +static inline inline u32 tpm2_rc_value(u32 rc) +{ + return (rc & BIT(7)) ? rc & 0xff : rc; +} + int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf); int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash); int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max); --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -529,7 +529,7 @@ out: tpm_buf_destroy(&buf); if (rc > 0) { - if ((rc & TPM2_RC_HASH) == TPM2_RC_HASH) + if (tpm2_rc_value(rc) == TPM2_RC_HASH) rc = -EINVAL; else rc = -EPERM;