[PATCH v7 21/21] tpm: use u32 instead of int for PCR index
From: Tomas Winkler
Date: Fri Oct 19 2018 - 14:28:25 EST
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@xxxxxxxxx>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
---
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;
--
2.14.4