From 58bac8cc3010ccb845572a3512fc16c9aaa5e50e Mon Sep 17 00:00:00 2001 From: Jarkko Sakkinen Date: Fri, 29 Jun 2018 15:24:50 +0300 Subject: [PATCH] tpm: replace TPM_TRANSMIT_RAW with TPM_TRANSMIT_NESTED As TPM_TRANSMIT_RAW always requires also not to take locks for obvious reasons (deadlock), this commit renames the flag as TPM_TRANSMIT_NESTED and prevents taking tpm_mutex when the flag is given to tpm_transmit(). Suggested-by: Tomas Winkler Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/tpm-interface.c | 13 ++++++------- drivers/char/tpm/tpm.h | 14 +++++++------- drivers/char/tpm/tpm2-space.c | 16 ++++++---------- drivers/char/tpm/tpm_vtpm_proxy.c | 2 +- 4 files changed, 20 insertions(+), 25 deletions(-) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index ad761e629a0f..1a803b0cf980 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -372,7 +372,7 @@ static int tpm_request_locality(struct tpm_chip *chip, unsigned int flags) { int rc; - if (flags & TPM_TRANSMIT_RAW) + if (flags & TPM_TRANSMIT_NESTED) return 0; if (!chip->ops->request_locality) @@ -391,7 +391,7 @@ static void tpm_relinquish_locality(struct tpm_chip *chip, unsigned int flags) { int rc; - if (flags & TPM_TRANSMIT_RAW) + if (flags & TPM_TRANSMIT_NESTED) return; if (!chip->ops->relinquish_locality) @@ -406,7 +406,7 @@ static void tpm_relinquish_locality(struct tpm_chip *chip, unsigned int flags) static int tpm_cmd_ready(struct tpm_chip *chip, unsigned int flags) { - if (flags & TPM_TRANSMIT_RAW) + if (flags & TPM_TRANSMIT_NESTED) return 0; if (!chip->ops->cmd_ready) @@ -417,7 +417,7 @@ static int tpm_cmd_ready(struct tpm_chip *chip, unsigned int flags) static int tpm_go_idle(struct tpm_chip *chip, unsigned int flags) { - if (flags & TPM_TRANSMIT_RAW) + if (flags & TPM_TRANSMIT_NESTED) return 0; if (!chip->ops->go_idle) @@ -466,10 +466,9 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, return -E2BIG; } - if (!(flags & TPM_TRANSMIT_UNLOCKED)) + if (!(flags & TPM_TRANSMIT_UNLOCKED) && !(flags & TPM_TRANSMIT_NESTED)) mutex_lock(&chip->tpm_mutex); - if (chip->ops->clk_enable != NULL) chip->ops->clk_enable(chip, true); @@ -559,7 +558,7 @@ out_no_locality: if (chip->ops->clk_enable != NULL) chip->ops->clk_enable(chip, false); - if (!(flags & TPM_TRANSMIT_UNLOCKED)) + if (!(flags & TPM_TRANSMIT_UNLOCKED) && !(flags & TPM_TRANSMIT_NESTED)) mutex_unlock(&chip->tpm_mutex); return rc ? rc : len; } diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index ba01488cd029..f3501d05264f 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -513,16 +513,16 @@ extern const struct file_operations tpmrm_fops; extern struct idr dev_nums_idr; /** - * enum tpm_transmit_flags + * enum tpm_transmit_flags - flags for tpm_transmit() * - * @TPM_TRANSMIT_UNLOCKED: used to lock sequence of tpm_transmit calls. - * @TPM_TRANSMIT_RAW: prevent recursive calls into setup steps - * (go idle, locality,..). Always use with UNLOCKED - * as it will fail on double locking. + * @TPM_TRANSMIT_UNLOCKED: do not lock the chip + * @TPM_TRANSMIT_NESTED: discard setup steps (power management, + * locality) including locking (i.e. implicit + * UNLOCKED) */ enum tpm_transmit_flags { - TPM_TRANSMIT_UNLOCKED = BIT(0), - TPM_TRANSMIT_RAW = BIT(1), + TPM_TRANSMIT_UNLOCKED = BIT(0), + TPM_TRANSMIT_NESTED = BIT(1), }; ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space, diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c index 11c85ed8c113..d2e101b32482 100644 --- a/drivers/char/tpm/tpm2-space.c +++ b/drivers/char/tpm/tpm2-space.c @@ -39,8 +39,7 @@ static void tpm2_flush_sessions(struct tpm_chip *chip, struct tpm_space *space) for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++) { if (space->session_tbl[i]) tpm2_flush_context_cmd(chip, space->session_tbl[i], - TPM_TRANSMIT_UNLOCKED | - TPM_TRANSMIT_RAW); + TPM_TRANSMIT_NESTED); } } @@ -85,7 +84,7 @@ static int tpm2_load_context(struct tpm_chip *chip, u8 *buf, tpm_buf_append(&tbuf, &buf[*offset], body_size); rc = tpm_transmit_cmd(chip, NULL, tbuf.data, PAGE_SIZE, 4, - TPM_TRANSMIT_UNLOCKED | TPM_TRANSMIT_RAW, NULL); + TPM_TRANSMIT_NESTED, NULL); if (rc < 0) { dev_warn(&chip->dev, "%s: failed with a system error %d\n", __func__, rc); @@ -134,7 +133,7 @@ static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf, tpm_buf_append_u32(&tbuf, handle); rc = tpm_transmit_cmd(chip, NULL, tbuf.data, PAGE_SIZE, 0, - TPM_TRANSMIT_UNLOCKED | TPM_TRANSMIT_RAW, NULL); + TPM_TRANSMIT_NESTED, NULL); if (rc < 0) { dev_warn(&chip->dev, "%s: failed with a system error %d\n", __func__, rc); @@ -171,8 +170,7 @@ static void tpm2_flush_space(struct tpm_chip *chip) for (i = 0; i < ARRAY_SIZE(space->context_tbl); i++) if (space->context_tbl[i] && ~space->context_tbl[i]) tpm2_flush_context_cmd(chip, space->context_tbl[i], - TPM_TRANSMIT_UNLOCKED | - TPM_TRANSMIT_RAW); + TPM_TRANSMIT_NESTED); tpm2_flush_sessions(chip, space); } @@ -379,8 +377,7 @@ static int tpm2_map_response_header(struct tpm_chip *chip, u32 cc, u8 *rsp, return 0; out_no_slots: - tpm2_flush_context_cmd(chip, phandle, - TPM_TRANSMIT_UNLOCKED | TPM_TRANSMIT_RAW); + tpm2_flush_context_cmd(chip, phandle, TPM_TRANSMIT_NESTED); dev_warn(&chip->dev, "%s: out of slots for 0x%08X\n", __func__, phandle); return -ENOMEM; @@ -468,8 +465,7 @@ static int tpm2_save_space(struct tpm_chip *chip) return rc; tpm2_flush_context_cmd(chip, space->context_tbl[i], - TPM_TRANSMIT_UNLOCKED | - TPM_TRANSMIT_RAW); + TPM_TRANSMIT_NESTED); space->context_tbl[i] = ~0; } diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c b/drivers/char/tpm/tpm_vtpm_proxy.c index e4f79f920450..87a0ce47f201 100644 --- a/drivers/char/tpm/tpm_vtpm_proxy.c +++ b/drivers/char/tpm/tpm_vtpm_proxy.c @@ -418,7 +418,7 @@ static int vtpm_proxy_request_locality(struct tpm_chip *chip, int locality) proxy_dev->state |= STATE_DRIVER_COMMAND; rc = tpm_transmit_cmd(chip, NULL, buf.data, tpm_buf_length(&buf), 0, - TPM_TRANSMIT_UNLOCKED | TPM_TRANSMIT_RAW, + TPM_TRANSMIT_NESTED, "attempting to set locality"); proxy_dev->state &= ~STATE_DRIVER_COMMAND;