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authorJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>2016-08-16 22:00:38 +0300
committerJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>2016-09-15 16:04:21 +0300
commitd4816edfe706497a8525480c1685ceb9871bc118 (patch)
tree73c4afa873f131ab70998332b9f4ece9e6f83d24 /drivers/char/tpm/tpm2-cmd.c
parentb7d7b28471072fc23e7b573aef89c14438092223 (diff)
tpm: fix a race condition in tpm2_unseal_trusted()
Unseal and load operations should be done as an atomic operation. This commit introduces unlocked tpm_transmit() so that tpm2_unseal_trusted() can do the locking by itself. Fixes: 0fe5480303a1 ("keys, trusted: seal/unseal with TPM 2.0 chips") Cc: stable@vger.kernel.org Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Diffstat (limited to 'drivers/char/tpm/tpm2-cmd.c')
-rw-r--r--drivers/char/tpm/tpm2-cmd.c101
1 files changed, 65 insertions, 36 deletions
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 0c75c3f1689f..ef5a58b986f6 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -282,7 +282,7 @@ int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
sizeof(cmd.params.pcrread_in.pcr_select));
cmd.params.pcrread_in.pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
- rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
+ rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0,
"attempting to read a pcr value");
if (rc == 0) {
buf = cmd.params.pcrread_out.digest;
@@ -330,7 +330,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash)
cmd.params.pcrextend_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
memcpy(cmd.params.pcrextend_in.digest, hash, TPM_DIGEST_SIZE);
- rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
+ rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0,
"attempting extend a PCR value");
return rc;
@@ -376,7 +376,7 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
cmd.header.in = tpm2_getrandom_header;
cmd.params.getrandom_in.size = cpu_to_be16(num_bytes);
- err = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
+ err = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0,
"attempting get random");
if (err)
break;
@@ -434,12 +434,12 @@ static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle,
}
/**
- * tpm2_seal_trusted() - seal a trusted key
- * @chip_num: A specific chip number for the request or TPM_ANY_NUM
- * @options: authentication values and other options
+ * tpm2_seal_trusted() - seal the payload of a trusted key
+ * @chip_num: TPM chip to use
* @payload: the key data in clear and encrypted form
+ * @options: authentication values and other options
*
- * Returns < 0 on error and 0 on success.
+ * Return: < 0 on error and 0 on success.
*/
int tpm2_seal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
@@ -512,7 +512,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
goto out;
}
- rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "sealing data");
+ rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 0, "sealing data");
if (rc)
goto out;
@@ -538,10 +538,18 @@ out:
return rc;
}
-static int tpm2_load(struct tpm_chip *chip,
- struct trusted_key_payload *payload,
- struct trusted_key_options *options,
- u32 *blob_handle)
+/**
+ * tpm2_load_cmd() - execute a TPM2_Load command
+ * @chip_num: TPM chip to use
+ * @payload: the key data in clear and encrypted form
+ * @options: authentication values and other options
+ *
+ * Return: same as with tpm_transmit_cmd
+ */
+static int tpm2_load_cmd(struct tpm_chip *chip,
+ struct trusted_key_payload *payload,
+ struct trusted_key_options *options,
+ u32 *blob_handle, unsigned int flags)
{
struct tpm_buf buf;
unsigned int private_len;
@@ -576,7 +584,7 @@ static int tpm2_load(struct tpm_chip *chip,
goto out;
}
- rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "loading blob");
+ rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, flags, "loading blob");
if (!rc)
*blob_handle = be32_to_cpup(
(__be32 *) &buf.data[TPM_HEADER_SIZE]);
@@ -590,7 +598,16 @@ out:
return rc;
}
-static void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
+/**
+ * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
+ * @chip_num: TPM chip to use
+ * @payload: the key data in clear and encrypted form
+ * @options: authentication values and other options
+ *
+ * Return: same as with tpm_transmit_cmd
+ */
+static void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
+ unsigned int flags)
{
struct tpm_buf buf;
int rc;
@@ -604,7 +621,8 @@ static void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
tpm_buf_append_u32(&buf, handle);
- rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "flushing context");
+ rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, flags,
+ "flushing context");
if (rc)
dev_warn(&chip->dev, "0x%08x was not flushed, rc=%d\n", handle,
rc);
@@ -612,10 +630,18 @@ static void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
tpm_buf_destroy(&buf);
}
-static int tpm2_unseal(struct tpm_chip *chip,
- struct trusted_key_payload *payload,
- struct trusted_key_options *options,
- u32 blob_handle)
+/**
+ * tpm2_unseal_cmd() - execute a TPM2_Unload command
+ * @chip_num: TPM chip to use
+ * @payload: the key data in clear and encrypted form
+ * @options: authentication values and other options
+ *
+ * Return: same as with tpm_transmit_cmd
+ */
+static int tpm2_unseal_cmd(struct tpm_chip *chip,
+ struct trusted_key_payload *payload,
+ struct trusted_key_options *options,
+ u32 blob_handle, unsigned int flags)
{
struct tpm_buf buf;
u16 data_len;
@@ -635,7 +661,7 @@ static int tpm2_unseal(struct tpm_chip *chip,
options->blobauth /* hmac */,
TPM_DIGEST_SIZE);
- rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "unsealing");
+ rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, flags, "unsealing");
if (rc > 0)
rc = -EPERM;
@@ -654,12 +680,12 @@ static int tpm2_unseal(struct tpm_chip *chip,
}
/**
- * tpm_unseal_trusted() - unseal a trusted key
- * @chip_num: A specific chip number for the request or TPM_ANY_NUM
- * @options: authentication values and other options
+ * tpm_unseal_trusted() - unseal the payload of a trusted key
+ * @chip_num: TPM chip to use
* @payload: the key data in clear and encrypted form
+ * @options: authentication values and other options
*
- * Returns < 0 on error and 0 on success.
+ * Return: < 0 on error and 0 on success.
*/
int tpm2_unseal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
@@ -668,14 +694,17 @@ int tpm2_unseal_trusted(struct tpm_chip *chip,
u32 blob_handle;
int rc;
- rc = tpm2_load(chip, payload, options, &blob_handle);
+ mutex_lock(&chip->tpm_mutex);
+ rc = tpm2_load_cmd(chip, payload, options, &blob_handle,
+ TPM_TRANSMIT_UNLOCKED);
if (rc)
- return rc;
-
- rc = tpm2_unseal(chip, payload, options, blob_handle);
-
- tpm2_flush_context(chip, blob_handle);
+ goto out;
+ rc = tpm2_unseal_cmd(chip, payload, options, blob_handle,
+ TPM_TRANSMIT_UNLOCKED);
+ tpm2_flush_context_cmd(chip, blob_handle, TPM_TRANSMIT_UNLOCKED);
+out:
+ mutex_unlock(&chip->tpm_mutex);
return rc;
}
@@ -701,7 +730,7 @@ ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value,
cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(property_id);
cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
- rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), desc);
+ rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0, desc);
if (!rc)
*value = be32_to_cpu(cmd.params.get_tpm_pt_out.value);
@@ -735,7 +764,7 @@ static int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
cmd.header.in = tpm2_startup_header;
cmd.params.startup_in.startup_type = cpu_to_be16(startup_type);
- return tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
+ return tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0,
"attempting to start the TPM");
}
@@ -763,7 +792,7 @@ void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
cmd.header.in = tpm2_shutdown_header;
cmd.params.startup_in.startup_type = cpu_to_be16(shutdown_type);
- rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), "stopping the TPM");
+ rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0, "stopping the TPM");
/* In places where shutdown command is sent there's no much we can do
* except print the error code on a system failure.
@@ -828,7 +857,7 @@ static int tpm2_start_selftest(struct tpm_chip *chip, bool full)
cmd.header.in = tpm2_selftest_header;
cmd.params.selftest_in.full_test = full;
- rc = tpm_transmit_cmd(chip, &cmd, TPM2_SELF_TEST_IN_SIZE,
+ rc = tpm_transmit_cmd(chip, &cmd, TPM2_SELF_TEST_IN_SIZE, 0,
"continue selftest");
/* At least some prototype chips seem to give RC_TESTING error
@@ -880,7 +909,7 @@ static int tpm2_do_selftest(struct tpm_chip *chip)
cmd.params.pcrread_in.pcr_select[1] = 0x00;
cmd.params.pcrread_in.pcr_select[2] = 0x00;
- rc = tpm_transmit_cmd(chip, (u8 *) &cmd, sizeof(cmd), NULL);
+ rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0, NULL);
if (rc < 0)
break;
@@ -928,7 +957,7 @@ int tpm2_probe(struct tpm_chip *chip)
cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
- rc = tpm_transmit(chip, (const char *) &cmd, sizeof(cmd));
+ rc = tpm_transmit(chip, (const u8 *)&cmd, sizeof(cmd), 0);
if (rc < 0)
return rc;
else if (rc < TPM_HEADER_SIZE)