From: Jarkko Sakkinen jarkko@kernel.org
commit 8c657a0590de585b1115847c17b34a58025f2f4b upstream.
When TPM 2.0 trusted keys code was moved to the trusted keys subsystem, the operations were unwrapped from tpm_try_get_ops() and tpm_put_ops(), which are used to take temporarily the ownership of the TPM chip. The ownership is only taken inside tpm_send(), but this is not sufficient, as in the key load TPM2_CC_LOAD, TPM2_CC_UNSEAL and TPM2_FLUSH_CONTEXT need to be done as a one single atom.
Take the TPM chip ownership before sending anything with tpm_try_get_ops() and tpm_put_ops(), and use tpm_transmit_cmd() to send TPM commands instead of tpm_send(), reverting back to the old behaviour.
Fixes: 2e19e10131a0 ("KEYS: trusted: Move TPM2 trusted keys code") Reported-by: "James E.J. Bottomley" James.Bottomley@HansenPartnership.com Cc: stable@vger.kernel.org Cc: David Howells dhowells@redhat.com Cc: Mimi Zohar zohar@linux.ibm.com Cc: Sumit Garg sumit.garg@linaro.org Acked-by Sumit Garg sumit.garg@linaro.org Tested-by: Mimi Zohar zohar@linux.ibm.com Signed-off-by: Jarkko Sakkinen jarkko@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/char/tpm/tpm.h | 4 ---- include/linux/tpm.h | 5 ++++- security/keys/trusted-keys/trusted_tpm2.c | 22 ++++++++++++++++++---- 3 files changed, 22 insertions(+), 9 deletions(-)
--- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -164,8 +164,6 @@ extern const struct file_operations tpmr extern struct idr dev_nums_idr;
ssize_t tpm_transmit(struct tpm_chip *chip, u8 *buf, size_t bufsiz); -ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_buf *buf, - size_t min_rsp_body_length, const char *desc); int tpm_get_timeouts(struct tpm_chip *); int tpm_auto_startup(struct tpm_chip *chip);
@@ -194,8 +192,6 @@ static inline void tpm_msleep(unsigned i int tpm_chip_start(struct tpm_chip *chip); void tpm_chip_stop(struct tpm_chip *chip); struct tpm_chip *tpm_find_get_ops(struct tpm_chip *chip); -__must_check int tpm_try_get_ops(struct tpm_chip *chip); -void tpm_put_ops(struct tpm_chip *chip);
struct tpm_chip *tpm_chip_alloc(struct device *dev, const struct tpm_class_ops *ops); --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -397,6 +397,10 @@ static inline u32 tpm2_rc_value(u32 rc) #if defined(CONFIG_TCG_TPM) || defined(CONFIG_TCG_TPM_MODULE)
extern int tpm_is_tpm2(struct tpm_chip *chip); +extern __must_check int tpm_try_get_ops(struct tpm_chip *chip); +extern void tpm_put_ops(struct tpm_chip *chip); +extern ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_buf *buf, + size_t min_rsp_body_length, const char *desc); extern int tpm_pcr_read(struct tpm_chip *chip, u32 pcr_idx, struct tpm_digest *digest); extern int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, @@ -410,7 +414,6 @@ static inline int tpm_is_tpm2(struct tpm { return -ENODEV; } - static inline int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, struct tpm_digest *digest) { --- a/security/keys/trusted-keys/trusted_tpm2.c +++ b/security/keys/trusted-keys/trusted_tpm2.c @@ -83,6 +83,12 @@ int tpm2_seal_trusted(struct tpm_chip *c if (rc) return rc;
+ rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE); + if (rc) { + tpm_put_ops(chip); + return rc; + } + tpm_buf_append_u32(&buf, options->keyhandle); tpm2_buf_append_auth(&buf, TPM2_RS_PW, NULL /* nonce */, 0, @@ -130,7 +136,7 @@ int tpm2_seal_trusted(struct tpm_chip *c goto out; }
- rc = tpm_send(chip, buf.data, tpm_buf_length(&buf)); + rc = tpm_transmit_cmd(chip, &buf, 4, "sealing data"); if (rc) goto out;
@@ -157,6 +163,7 @@ out: rc = -EPERM; }
+ tpm_put_ops(chip); return rc; }
@@ -211,7 +218,7 @@ static int tpm2_load_cmd(struct tpm_chip goto out; }
- rc = tpm_send(chip, buf.data, tpm_buf_length(&buf)); + rc = tpm_transmit_cmd(chip, &buf, 4, "loading blob"); if (!rc) *blob_handle = be32_to_cpup( (__be32 *) &buf.data[TPM_HEADER_SIZE]); @@ -260,7 +267,7 @@ static int tpm2_unseal_cmd(struct tpm_ch options->blobauth /* hmac */, TPM_DIGEST_SIZE);
- rc = tpm_send(chip, buf.data, tpm_buf_length(&buf)); + rc = tpm_transmit_cmd(chip, &buf, 6, "unsealing"); if (rc > 0) rc = -EPERM;
@@ -304,12 +311,19 @@ int tpm2_unseal_trusted(struct tpm_chip u32 blob_handle; int rc;
- rc = tpm2_load_cmd(chip, payload, options, &blob_handle); + rc = tpm_try_get_ops(chip); if (rc) return rc;
+ rc = tpm2_load_cmd(chip, payload, options, &blob_handle); + if (rc) + goto out; + rc = tpm2_unseal_cmd(chip, payload, options, blob_handle); tpm2_flush_context(chip, blob_handle);
+out: + tpm_put_ops(chip); + return rc; }