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path: root/drivers/char/tpm/tpm-chip.c
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Diffstat (limited to 'drivers/char/tpm/tpm-chip.c')
-rw-r--r--drivers/char/tpm/tpm-chip.c142
1 files changed, 42 insertions, 100 deletions
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index c10a4aa97373..082b910ddf0d 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -28,8 +28,13 @@
DEFINE_IDR(dev_nums_idr);
static DEFINE_MUTEX(idr_lock);
-struct class *tpm_class;
-struct class *tpmrm_class;
+const struct class tpm_class = {
+ .name = "tpm",
+ .shutdown_pre = tpm_class_shutdown,
+};
+const struct class tpmrm_class = {
+ .name = "tpmrm",
+};
dev_t tpm_devt;
static int tpm_request_locality(struct tpm_chip *chip)
@@ -153,6 +158,9 @@ int tpm_try_get_ops(struct tpm_chip *chip)
{
int rc = -EIO;
+ if (chip->flags & TPM_CHIP_FLAG_DISABLE)
+ return rc;
+
get_device(&chip->dev);
down_read(&chip->ops_sem);
@@ -160,6 +168,11 @@ int tpm_try_get_ops(struct tpm_chip *chip)
goto out_ops;
mutex_lock(&chip->tpm_mutex);
+
+ /* tmp_chip_start may issue IO that is denied while suspended */
+ if (chip->flags & TPM_CHIP_FLAG_SUSPENDED)
+ goto out_lock;
+
rc = tpm_chip_start(chip);
if (rc)
goto out_lock;
@@ -218,42 +231,6 @@ struct tpm_chip *tpm_default_chip(void)
EXPORT_SYMBOL_GPL(tpm_default_chip);
/**
- * tpm_find_get_ops() - find and reserve a TPM chip
- * @chip: a &struct tpm_chip instance, %NULL for the default chip
- *
- * Finds a TPM chip and reserves its class device and operations. The chip must
- * be released with tpm_put_ops() after use.
- * This function is for internal use only. It supports existing TPM callers
- * by accepting NULL, but those callers should be converted to pass in a chip
- * directly.
- *
- * Return:
- * A reserved &struct tpm_chip instance.
- * %NULL if a chip is not found.
- * %NULL if the chip is not available.
- */
-struct tpm_chip *tpm_find_get_ops(struct tpm_chip *chip)
-{
- int rc;
-
- if (chip) {
- if (!tpm_try_get_ops(chip))
- return chip;
- return NULL;
- }
-
- chip = tpm_default_chip();
- if (!chip)
- return NULL;
- rc = tpm_try_get_ops(chip);
- /* release additional reference we got from tpm_default_chip() */
- put_device(&chip->dev);
- if (rc)
- return NULL;
- return chip;
-}
-
-/**
* tpm_dev_release() - free chip memory and the device number
* @dev: the character device for the TPM chip
*
@@ -269,7 +246,9 @@ static void tpm_dev_release(struct device *dev)
kfree(chip->work_space.context_buf);
kfree(chip->work_space.session_buf);
- kfree(chip->allocated_banks);
+#ifdef CONFIG_TCG_TPM2_HMAC
+ kfree(chip->auth);
+#endif
kfree(chip);
}
@@ -289,6 +268,7 @@ int tpm_class_shutdown(struct device *dev)
down_write(&chip->ops_sem);
if (chip->flags & TPM_CHIP_FLAG_TPM2) {
if (!tpm_chip_start(chip)) {
+ tpm2_end_auth_session(chip);
tpm2_shutdown(chip, TPM2_SU_CLEAR);
tpm_chip_stop(chip);
}
@@ -336,7 +316,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
device_initialize(&chip->dev);
- chip->dev.class = tpm_class;
+ chip->dev.class = &tpm_class;
chip->dev.release = tpm_dev_release;
chip->dev.parent = pdev;
chip->dev.groups = chip->groups;
@@ -510,74 +490,27 @@ static int tpm_add_legacy_sysfs(struct tpm_chip *chip)
return 0;
}
-/*
- * Some AMD fTPM versions may cause stutter
- * https://www.amd.com/en/support/kb/faq/pa-410
- *
- * Fixes are available in two series of fTPM firmware:
- * 6.x.y.z series: 6.0.18.6 +
- * 3.x.y.z series: 3.57.y.5 +
- */
-static bool tpm_amd_is_rng_defective(struct tpm_chip *chip)
+static int tpm_hwrng_read(struct hwrng *rng, void *data, size_t max, bool wait)
{
- u32 val1, val2;
- u64 version;
- int ret;
+ struct tpm_chip *chip = container_of(rng, struct tpm_chip, hwrng);
- if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
- return false;
+ return tpm_get_random(chip, data, max);
+}
- ret = tpm_request_locality(chip);
- if (ret)
+static bool tpm_is_hwrng_enabled(struct tpm_chip *chip)
+{
+ if (!IS_ENABLED(CONFIG_HW_RANDOM_TPM))
return false;
-
- ret = tpm2_get_tpm_pt(chip, TPM2_PT_MANUFACTURER, &val1, NULL);
- if (ret)
- goto release;
- if (val1 != 0x414D4400U /* AMD */) {
- ret = -ENODEV;
- goto release;
- }
- ret = tpm2_get_tpm_pt(chip, TPM2_PT_FIRMWARE_VERSION_1, &val1, NULL);
- if (ret)
- goto release;
- ret = tpm2_get_tpm_pt(chip, TPM2_PT_FIRMWARE_VERSION_2, &val2, NULL);
-
-release:
- tpm_relinquish_locality(chip);
-
- if (ret)
+ if (tpm_is_firmware_upgrade(chip))
return false;
-
- version = ((u64)val1 << 32) | val2;
- if ((version >> 48) == 6) {
- if (version >= 0x0006000000180006ULL)
- return false;
- } else if ((version >> 48) == 3) {
- if (version >= 0x0003005700000005ULL)
- return false;
- } else {
+ if (chip->flags & TPM_CHIP_FLAG_HWRNG_DISABLED)
return false;
- }
-
- dev_warn(&chip->dev,
- "AMD fTPM version 0x%llx causes system stutter; hwrng disabled\n",
- version);
-
return true;
}
-static int tpm_hwrng_read(struct hwrng *rng, void *data, size_t max, bool wait)
-{
- struct tpm_chip *chip = container_of(rng, struct tpm_chip, hwrng);
-
- return tpm_get_random(chip, data, max);
-}
-
static int tpm_add_hwrng(struct tpm_chip *chip)
{
- if (!IS_ENABLED(CONFIG_HW_RANDOM_TPM) || tpm_is_firmware_upgrade(chip) ||
- tpm_amd_is_rng_defective(chip))
+ if (!tpm_is_hwrng_enabled(chip))
return 0;
snprintf(chip->hwrng_name, sizeof(chip->hwrng_name),
@@ -682,7 +615,7 @@ int tpm_chip_register(struct tpm_chip *chip)
return 0;
out_hwrng:
- if (IS_ENABLED(CONFIG_HW_RANDOM_TPM) && !tpm_is_firmware_upgrade(chip))
+ if (tpm_is_hwrng_enabled(chip))
hwrng_unregister(&chip->hwrng);
out_ppi:
tpm_bios_log_teardown(chip);
@@ -706,9 +639,18 @@ EXPORT_SYMBOL_GPL(tpm_chip_register);
*/
void tpm_chip_unregister(struct tpm_chip *chip)
{
+#ifdef CONFIG_TCG_TPM2_HMAC
+ int rc;
+
+ rc = tpm_try_get_ops(chip);
+ if (!rc) {
+ tpm2_end_auth_session(chip);
+ tpm_put_ops(chip);
+ }
+#endif
+
tpm_del_legacy_sysfs(chip);
- if (IS_ENABLED(CONFIG_HW_RANDOM_TPM) && !tpm_is_firmware_upgrade(chip) &&
- !tpm_amd_is_rng_defective(chip))
+ if (tpm_is_hwrng_enabled(chip))
hwrng_unregister(&chip->hwrng);
tpm_bios_log_teardown(chip);
if (chip->flags & TPM_CHIP_FLAG_TPM2 && !tpm_is_firmware_upgrade(chip))