[PATCH v7 21/21] tpm: use u32 instead of int for PCR index
Jarkko Sakkinen
jarkko.sakkinen at linux.intel.com
Tue Oct 23 18:55:03 UTC 2018
On Fri, 19 Oct 2018, Tomas Winkler wrote:
> The TPM specs defines PCR index as a positive number, and there is
> no reason to use a signed number. It is also a possible security
> issue as currently no functions check for a negative index,
> which may become a large number when converted to u32.
>
> Adjust the API to use u32 instead of int in all PCR related
> functions.
>
> Signed-off-by: Tomas Winkler <tomas.winkler at intel.com>
> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen at linux.intel.com>
> Tested-by: Jarkko Sakkinen <jarkko.sakkinen at linux.intel.com>
> ---
> V3: New in the series.
> V4: Separate unrelated change to another patches.
> V5: Fix the commit message.
> V6: Rebased.
> V7: Resend.
>
> drivers/char/tpm/tpm-interface.c | 6 +++---
> drivers/char/tpm/tpm-sysfs.c | 2 +-
> drivers/char/tpm/tpm.h | 10 +++++-----
> drivers/char/tpm/tpm1-cmd.c | 6 +++---
> drivers/char/tpm/tpm2-cmd.c | 5 ++---
> include/linux/tpm.h | 11 +++++++----
> security/integrity/ima/ima_crypto.c | 5 +++--
> 7 files changed, 24 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> index acd647476ae1..d9439f9abe78 100644
> --- a/drivers/char/tpm/tpm-interface.c
> +++ b/drivers/char/tpm/tpm-interface.c
> @@ -38,7 +38,7 @@
> * recently changed pcr on suspend, so force the flush
> * with an extend to the selected _unused_ non-volatile pcr.
> */
> -static int tpm_suspend_pcr;
> +static u32 tpm_suspend_pcr;
> module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
> MODULE_PARM_DESC(suspend_pcr,
> "PCR to use for dummy writes to facilitate flush on suspend.");
> @@ -455,7 +455,7 @@ EXPORT_SYMBOL_GPL(tpm_is_tpm2);
> *
> * Return: same as with tpm_transmit_cmd()
> */
> -int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
> +int tpm_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
> {
> int rc;
>
> @@ -485,7 +485,7 @@ EXPORT_SYMBOL_GPL(tpm_pcr_read);
> *
> * Return: same as with tpm_transmit_cmd()
> */
> -int tpm_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash)
> +int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash)
> {
> int rc;
> struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)];
> diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
> index 96fc7433c57d..b88e08ec2c59 100644
> --- a/drivers/char/tpm/tpm-sysfs.c
> +++ b/drivers/char/tpm/tpm-sysfs.c
> @@ -102,7 +102,7 @@ static ssize_t pcrs_show(struct device *dev, struct device_attribute *attr,
> cap_t cap;
> u8 digest[TPM_DIGEST_SIZE];
> ssize_t rc;
> - int i, j, num_pcrs;
> + u32 i, j, num_pcrs;
> char *str = buf;
> struct tpm_chip *chip = to_tpm_chip(dev);
>
> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> index e0778d19da98..f27d1f38a93d 100644
> --- a/drivers/char/tpm/tpm.h
> +++ b/drivers/char/tpm/tpm.h
> @@ -509,14 +509,14 @@ ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space,
> int tpm_get_timeouts(struct tpm_chip *);
> int tpm_auto_startup(struct tpm_chip *chip);
>
> -int tpm1_pm_suspend(struct tpm_chip *chip, int tpm_suspend_pcr);
> +int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr);
> int tpm1_auto_startup(struct tpm_chip *chip);
> int tpm1_do_selftest(struct tpm_chip *chip);
> int tpm1_get_timeouts(struct tpm_chip *chip);
> unsigned long tpm1_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal);
> -int tpm1_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash,
> +int tpm1_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash,
> const char *log_msg);
> -int tpm1_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf);
> +int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf);
> ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
> const char *desc, size_t min_cap_length);
> int tpm1_get_random(struct tpm_chip *chip, u8 *out, size_t max);
> @@ -558,8 +558,8 @@ static inline u32 tpm2_rc_value(u32 rc)
> }
>
> int tpm2_get_timeouts(struct tpm_chip *chip);
> -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, u32 count,
> +int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf);
> +int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, u32 count,
> struct tpm2_digest *digests);
> int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max);
> void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
> diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c
> index 6b04648f8184..6f306338953b 100644
> --- a/drivers/char/tpm/tpm1-cmd.c
> +++ b/drivers/char/tpm/tpm1-cmd.c
> @@ -449,7 +449,7 @@ int tpm1_get_timeouts(struct tpm_chip *chip)
> }
>
> #define TPM_ORD_PCR_EXTEND 20
> -int tpm1_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash,
> +int tpm1_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash,
> const char *log_msg)
> {
> struct tpm_buf buf;
> @@ -572,7 +572,7 @@ int tpm1_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
> }
>
> #define TPM_ORD_PCRREAD 21
> -int tpm1_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
> +int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
> {
> struct tpm_buf buf;
> int rc;
> @@ -729,7 +729,7 @@ int tpm1_auto_startup(struct tpm_chip *chip)
> * * 0 on success,
> * * < 0 on error.
> */
> -int tpm1_pm_suspend(struct tpm_chip *chip, int tpm_suspend_pcr)
> +int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr)
> {
> u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
> struct tpm_buf buf;
> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> index 6ca4fc0a0d6f..ae86fb0218ab 100644
> --- a/drivers/char/tpm/tpm2-cmd.c
> +++ b/drivers/char/tpm/tpm2-cmd.c
> @@ -175,7 +175,7 @@ struct tpm2_pcr_read_out {
> *
> * Return: Same as with tpm_transmit_cmd.
> */
> -int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
> +int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
> {
> int rc;
> struct tpm_buf buf;
> @@ -225,7 +225,7 @@ struct tpm2_null_auth_area {
> *
> * Return: Same as with tpm_transmit_cmd.
> */
> -int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count,
> +int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, u32 count,
> struct tpm2_digest *digests)
> {
> struct tpm_buf buf;
> @@ -272,7 +272,6 @@ int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count,
> return rc;
> }
>
> -
> struct tpm2_get_random_out {
> __be16 size;
> u8 buffer[TPM_MAX_RNG_DATA];
> diff --git a/include/linux/tpm.h b/include/linux/tpm.h
> index 4609b94142d4..b49a55cf775f 100644
> --- a/include/linux/tpm.h
> +++ b/include/linux/tpm.h
> @@ -53,8 +53,8 @@ struct tpm_class_ops {
> #if defined(CONFIG_TCG_TPM) || defined(CONFIG_TCG_TPM_MODULE)
>
> extern int tpm_is_tpm2(struct tpm_chip *chip);
> -extern int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf);
> -extern int tpm_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash);
> +extern int tpm_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf);
> +extern int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash);
> extern int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen);
> extern int tpm_get_random(struct tpm_chip *chip, u8 *data, size_t max);
> extern int tpm_seal_trusted(struct tpm_chip *chip,
> @@ -69,15 +69,18 @@ static inline int tpm_is_tpm2(struct tpm_chip *chip)
> {
> return -ENODEV;
> }
> -static inline int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
> +
> +static inline int tpm_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
> {
> return -ENODEV;
> }
> -static inline int tpm_pcr_extend(struct tpm_chip *chip, int pcr_idx,
> +
> +static inline int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
> const u8 *hash)
> {
> return -ENODEV;
> }
> +
> static inline int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen)
> {
> return -ENODEV;
> diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
> index 7e7e7e7c250a..959d9edc113a 100644
> --- a/security/integrity/ima/ima_crypto.c
> +++ b/security/integrity/ima/ima_crypto.c
> @@ -629,7 +629,7 @@ int ima_calc_buffer_hash(const void *buf, loff_t len,
> return calc_buffer_shash(buf, len, hash);
> }
>
> -static void __init ima_pcrread(int idx, u8 *pcr)
> +static void __init ima_pcrread(u32 idx, u8 *pcr)
> {
> if (!ima_tpm_chip)
> return;
> @@ -645,7 +645,8 @@ static int __init ima_calc_boot_aggregate_tfm(char *digest,
> struct crypto_shash *tfm)
> {
> u8 pcr_i[TPM_DIGEST_SIZE];
> - int rc, i;
> + int rc;
> + u32 i;
> SHASH_DESC_ON_STACK(shash, tfm);
>
> shash->tfm = tfm;
>
All commits have been now applied.
/Jarkko
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