diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 19f820f775b5..af355bd97bea 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -328,7 +328,7 @@ unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, } EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration); -static bool tpm_validate_command(struct tpm_chip *chip, +static int tpm_validate_command(struct tpm_chip *chip, struct tpm_space *space, const u8 *cmd, size_t len) @@ -340,10 +340,10 @@ static bool tpm_validate_command(struct tpm_chip *chip, unsigned int nr_handles; if (len < TPM_HEADER_SIZE) - return false; + return -EINVAL; if (!space) - return true; + return 0; if (chip->flags & TPM_CHIP_FLAG_TPM2 && chip->nr_commands) { cc = be32_to_cpu(header->ordinal); @@ -352,7 +352,7 @@ static bool tpm_validate_command(struct tpm_chip *chip, if (i < 0) { dev_dbg(&chip->dev, "0x%04X is an invalid command\n", cc); - return false; + return -EOPNOTSUPP; } attrs = chip->cc_attrs_tbl[i]; @@ -362,11 +362,11 @@ static bool tpm_validate_command(struct tpm_chip *chip, goto err_len; } - return true; + return 0; err_len: dev_dbg(&chip->dev, "%s: insufficient command length %zu", __func__, len); - return false; + return -EINVAL; } /** @@ -391,8 +391,20 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space, unsigned long stop; bool need_locality; - if (!tpm_validate_command(chip, space, buf, bufsiz)) - return -EINVAL; + rc = tpm_validate_command(chip, space, buf, bufsiz); + if (rc == -EINVAL) + return rc; + /* + * If the command is not implemented by the TPM, synthesize a + * response with a TPM2_RC_COMMAND_CODE return for user-space. + */ + if (rc == -EOPNOTSUPP) { + header->length = cpu_to_be32(sizeof(*header)); + header->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS); + header->return_code = cpu_to_be32(TPM2_RC_COMMAND_CODE | + TSS2_RESMGR_TPM_RC_LAYER); + return bufsiz; + } if (bufsiz > TPM_BUFSIZE) bufsiz = TPM_BUFSIZE; diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 605c0be2b8dc..f895fba4e20d 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -95,12 +95,17 @@ enum tpm2_structures { TPM2_ST_SESSIONS = 0x8002, }; +/* Indicates from what layer of the software stack the error comes from */ +#define TSS2_RC_LAYER_SHIFT 16 +#define TSS2_RESMGR_TPM_RC_LAYER (11 << TSS2_RC_LAYER_SHIFT) + enum tpm2_return_codes { TPM2_RC_SUCCESS = 0x0000, TPM2_RC_HASH = 0x0083, /* RC_FMT1 */ TPM2_RC_HANDLE = 0x008B, TPM2_RC_INITIALIZE = 0x0100, /* RC_VER1 */ TPM2_RC_DISABLED = 0x0120, + TPM2_RC_COMMAND_CODE = 0x0143, TPM2_RC_TESTING = 0x090A, /* RC_WARN */ TPM2_RC_REFERENCE_H0 = 0x0910, };