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path: root/drivers/char/tpm/tpm-interface.c
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Diffstat (limited to 'drivers/char/tpm/tpm-interface.c')
-rw-r--r--drivers/char/tpm/tpm-interface.c70
1 files changed, 49 insertions, 21 deletions
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index a3461cb..2ea16ab 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -423,8 +423,9 @@ out:
* The function extracts tpm out header return code
*
* @chip: TPM chip to use
- * @cmd: TPM command buffer
- * @len: length of the TPM command
+ * @buf: TPM command buffer
+ * @bufsiz: length of the buffer
+ * @min_rsp_body_length: minimum expected length of response body
* @flags: tpm transmit flags - bitmap
* @desc: command description used in the error message
*
@@ -433,26 +434,35 @@ out:
* A negative number for system errors (errno).
* A positive number for a TPM error.
*/
-ssize_t tpm_transmit_cmd(struct tpm_chip *chip, const void *cmd,
- int len, unsigned int flags, const char *desc)
+ssize_t tpm_transmit_cmd(struct tpm_chip *chip, const void *buf,
+ size_t bufsiz, size_t min_rsp_body_length,
+ unsigned int flags, const char *desc)
{
const struct tpm_output_header *header;
int err;
+ ssize_t len;
- len = tpm_transmit(chip, (const u8 *)cmd, len, flags);
+ len = tpm_transmit(chip, (const u8 *)buf, bufsiz, flags);
if (len < 0)
return len;
else if (len < TPM_HEADER_SIZE)
return -EFAULT;
- header = cmd;
+ header = buf;
+ if (len != be32_to_cpu(header->length))
+ return -EFAULT;
err = be32_to_cpu(header->return_code);
if (err != 0 && desc)
dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err,
desc);
+ if (err)
+ return err;
+
+ if (len < min_rsp_body_length + TPM_HEADER_SIZE)
+ return -EFAULT;
- return err;
+ return 0;
}
#define TPM_DIGEST_SIZE 20
@@ -468,7 +478,7 @@ static const struct tpm_input_header tpm_getcap_header = {
};
ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
- const char *desc)
+ const char *desc, size_t min_cap_length)
{
struct tpm_cmd_t tpm_cmd;
int rc;
@@ -491,8 +501,8 @@ ssize_t tpm_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
tpm_cmd.params.getcap_in.subcap = cpu_to_be32(subcap_id);
}
- rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
- desc);
+ rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
+ min_cap_length, 0, desc);
if (!rc)
*cap = tpm_cmd.params.getcap_out.cap;
return rc;
@@ -516,7 +526,7 @@ static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
start_cmd.params.startup_in.startup_type = startup_type;
return tpm_transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE, 0,
- "attempting to start the TPM");
+ 0, "attempting to start the TPM");
}
int tpm_get_timeouts(struct tpm_chip *chip)
@@ -545,7 +555,8 @@ int tpm_get_timeouts(struct tpm_chip *chip)
return 0;
}
- rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL);
+ rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL,
+ sizeof(cap.timeout));
if (rc == TPM_ERR_INVALID_POSTINIT) {
/* The TPM is not started, we are the first to talk to it.
Execute a startup command. */
@@ -554,8 +565,10 @@ int tpm_get_timeouts(struct tpm_chip *chip)
return rc;
rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
- "attempting to determine the timeouts");
+ "attempting to determine the timeouts",
+ sizeof(cap.timeout));
}
+
if (rc) {
dev_err(&chip->dev,
"A TPM error (%zd) occurred attempting to determine the timeouts\n",
@@ -617,7 +630,8 @@ int tpm_get_timeouts(struct tpm_chip *chip)
chip->timeout_d = usecs_to_jiffies(timeout_eff[3]);
rc = tpm_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
- "attempting to determine the durations");
+ "attempting to determine the durations",
+ sizeof(cap.duration));
if (rc)
return rc;
@@ -668,13 +682,14 @@ static int tpm_continue_selftest(struct tpm_chip *chip)
struct tpm_cmd_t cmd;
cmd.header.in = continue_selftest_header;
- rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE, 0,
+ rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE, 0, 0,
"continue selftest");
return rc;
}
#define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
#define READ_PCR_RESULT_SIZE 30
+#define READ_PCR_RESULT_BODY_SIZE 20
static const struct tpm_input_header pcrread_header = {
.tag = TPM_TAG_RQU_COMMAND,
.length = cpu_to_be32(14),
@@ -688,7 +703,8 @@ int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
cmd.header.in = pcrread_header;
cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
- rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE, 0,
+ rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
+ READ_PCR_RESULT_BODY_SIZE, 0,
"attempting to read a pcr value");
if (rc == 0)
@@ -751,6 +767,7 @@ EXPORT_SYMBOL_GPL(tpm_pcr_read);
#define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
#define EXTEND_PCR_RESULT_SIZE 34
+#define EXTEND_PCR_RESULT_BODY_SIZE 24
static const struct tpm_input_header pcrextend_header = {
.tag = TPM_TAG_RQU_COMMAND,
.length = cpu_to_be32(34),
@@ -786,7 +803,8 @@ int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
cmd.header.in = pcrextend_header;
cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
- rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 0,
+ rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
+ EXTEND_PCR_RESULT_BODY_SIZE, 0,
"attempting extend a PCR value");
tpm_put_ops(chip);
@@ -890,7 +908,7 @@ int tpm_send(u32 chip_num, void *cmd, size_t buflen)
if (chip == NULL)
return -ENODEV;
- rc = tpm_transmit_cmd(chip, cmd, buflen, 0, "attempting tpm_cmd");
+ rc = tpm_transmit_cmd(chip, cmd, buflen, 0, 0, "attempting tpm_cmd");
tpm_put_ops(chip);
return rc;
@@ -992,7 +1010,8 @@ int tpm_pm_suspend(struct device *dev)
cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
TPM_DIGEST_SIZE);
- rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE, 0,
+ rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
+ EXTEND_PCR_RESULT_BODY_SIZE, 0,
"extending dummy pcr before suspend");
}
@@ -1000,7 +1019,7 @@ int tpm_pm_suspend(struct device *dev)
for (try = 0; try < TPM_RETRY; try++) {
cmd.header.in = savestate_header;
rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, 0,
- NULL);
+ 0, NULL);
/*
* If the TPM indicates that it is too busy to respond to
@@ -1062,7 +1081,7 @@ int tpm_get_random(u32 chip_num, u8 *out, size_t max)
{
struct tpm_chip *chip;
struct tpm_cmd_t tpm_cmd;
- u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
+ u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA), rlength;
int err, total = 0, retries = 5;
u8 *dest = out;
@@ -1085,11 +1104,20 @@ int tpm_get_random(u32 chip_num, u8 *out, size_t max)
err = tpm_transmit_cmd(chip, &tpm_cmd,
TPM_GETRANDOM_RESULT_SIZE + num_bytes,
+ offsetof(struct tpm_getrandom_out,
+ rng_data),
0, "attempting get random");
if (err)
break;
recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
+
+ rlength = be32_to_cpu(tpm_cmd.header.out.length);
+ if (rlength < offsetof(struct tpm_getrandom_out, rng_data) +
+ recd) {
+ total = -EFAULT;
+ break;
+ }
memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
dest += recd;
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