* [PATCH v4] tpm: Managed allocations for tpm_buf instances
@ 2025-07-01 14:51 Jarkko Sakkinen
2025-07-01 21:42 ` Stefan Berger
` (2 more replies)
0 siblings, 3 replies; 7+ messages in thread
From: Jarkko Sakkinen @ 2025-07-01 14:51 UTC (permalink / raw)
To: linux-kernel
Cc: keyrings, Stefan Berger, Jarkko Sakkinen, Peter Huewe,
Jarkko Sakkinen, Jason Gunthorpe, James Bottomley, Mimi Zohar,
David Howells, Paul Moore, James Morris, Serge E. Hallyn,
open list:TPM DEVICE DRIVER, open list:SECURITY SUBSYSTEM
From: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
Repeal and replace tpm_buf_init() and tpm_buf_init_sized() with
tpm_buf_alloc(), which returns a buffer of memory with the struct tpm_buf
header at the beginning of the returned buffer. This leaves 4090 bytes of
free space for the payload.
Given that kfree() is now the destructor for struct tpm_buf instances,
tpm_buf_destroy() becomes obsolete, and can be safely wiped of too.
The actual gist is that now a tpm_buf can be now declared using
__free(kfree) declared in linux/slab.h:
struct tpm_buf *buf __free(kfree) = NULL;
/* ... */
buf = tpm_buf_alloc();
Doing this has two-folded benefits:
1. Yet to be discoverd memory leaks in the pre-existing code base.
2. Memory leaks concerning new features and other contributions.
In addition, the barrier to contribute is lowered given that managing
memory is a factor easier.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
---
v4:
- Wrote a more a descriptive short summary and improved description.
- Fixed the error in documentation: there is 4090 bytes of space left
for the payload - not 4088 bytes.
- Turned tpm_buf_alloc() into inline function.
v3:
- Removed the cleanup class and moved on using __free(kfree) instead.
- Removed `buf_size` (James).
- I'm open for the idea of splitting still (Jason) but I'll hold
at least this revision just to check that my core idea here
is correct.
v2:
- Implement also memory allocation using the cleanup class.
- Rewrote the commit message.
- Implemented CLASS_TPM_BUF() helper macro.
---
drivers/char/tpm/tpm-buf.c | 42 ----
drivers/char/tpm/tpm-sysfs.c | 20 +-
drivers/char/tpm/tpm1-cmd.c | 150 ++++++------
drivers/char/tpm/tpm2-cmd.c | 272 ++++++++++------------
drivers/char/tpm/tpm2-sessions.c | 122 +++++-----
drivers/char/tpm/tpm2-space.c | 44 ++--
drivers/char/tpm/tpm_vtpm_proxy.c | 30 ++-
include/linux/tpm.h | 31 ++-
security/keys/trusted-keys/trusted_tpm1.c | 35 +--
security/keys/trusted-keys/trusted_tpm2.c | 157 ++++++-------
10 files changed, 413 insertions(+), 490 deletions(-)
diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c
index dc882fc9fa9e..b525c0dc9a6b 100644
--- a/drivers/char/tpm/tpm-buf.c
+++ b/drivers/char/tpm/tpm-buf.c
@@ -7,25 +7,6 @@
#include <linux/module.h>
#include <linux/tpm.h>
-/**
- * tpm_buf_init() - Allocate and initialize a TPM command
- * @buf: A &tpm_buf
- * @tag: TPM_TAG_RQU_COMMAND, TPM2_ST_NO_SESSIONS or TPM2_ST_SESSIONS
- * @ordinal: A command ordinal
- *
- * Return: 0 or -ENOMEM
- */
-int tpm_buf_init(struct tpm_buf *buf, u16 tag, u32 ordinal)
-{
- buf->data = (u8 *)__get_free_page(GFP_KERNEL);
- if (!buf->data)
- return -ENOMEM;
-
- tpm_buf_reset(buf, tag, ordinal);
- return 0;
-}
-EXPORT_SYMBOL_GPL(tpm_buf_init);
-
/**
* tpm_buf_reset() - Initialize a TPM command
* @buf: A &tpm_buf
@@ -48,23 +29,6 @@ void tpm_buf_reset(struct tpm_buf *buf, u16 tag, u32 ordinal)
}
EXPORT_SYMBOL_GPL(tpm_buf_reset);
-/**
- * tpm_buf_init_sized() - Allocate and initialize a sized (TPM2B) buffer
- * @buf: A @tpm_buf
- *
- * Return: 0 or -ENOMEM
- */
-int tpm_buf_init_sized(struct tpm_buf *buf)
-{
- buf->data = (u8 *)__get_free_page(GFP_KERNEL);
- if (!buf->data)
- return -ENOMEM;
-
- tpm_buf_reset_sized(buf);
- return 0;
-}
-EXPORT_SYMBOL_GPL(tpm_buf_init_sized);
-
/**
* tpm_buf_reset_sized() - Initialize a sized buffer
* @buf: A &tpm_buf
@@ -78,12 +42,6 @@ void tpm_buf_reset_sized(struct tpm_buf *buf)
}
EXPORT_SYMBOL_GPL(tpm_buf_reset_sized);
-void tpm_buf_destroy(struct tpm_buf *buf)
-{
- free_page((unsigned long)buf->data);
-}
-EXPORT_SYMBOL_GPL(tpm_buf_destroy);
-
/**
* tpm_buf_length() - Return the number of bytes consumed by the data
* @buf: A &tpm_buf
diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
index 94231f052ea7..9aaebd8057d4 100644
--- a/drivers/char/tpm/tpm-sysfs.c
+++ b/drivers/char/tpm/tpm-sysfs.c
@@ -32,28 +32,30 @@ struct tpm_readpubek_out {
static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
- struct tpm_buf tpm_buf;
+ struct tpm_buf *tpm_buf __free(kfree) = NULL;
struct tpm_readpubek_out *out;
int i;
char *str = buf;
struct tpm_chip *chip = to_tpm_chip(dev);
char anti_replay[20];
+ tpm_buf = tpm_buf_alloc();
+ if (!tpm_buf)
+ return -ENOMEM;
+
memset(&anti_replay, 0, sizeof(anti_replay));
if (tpm_try_get_ops(chip))
return 0;
- if (tpm_buf_init(&tpm_buf, TPM_TAG_RQU_COMMAND, TPM_ORD_READPUBEK))
- goto out_ops;
-
- tpm_buf_append(&tpm_buf, anti_replay, sizeof(anti_replay));
+ tpm_buf_reset(tpm_buf, TPM_TAG_RQU_COMMAND, TPM_ORD_READPUBEK);
+ tpm_buf_append(tpm_buf, anti_replay, sizeof(anti_replay));
- if (tpm_transmit_cmd(chip, &tpm_buf, READ_PUBEK_RESULT_MIN_BODY_SIZE,
+ if (tpm_transmit_cmd(chip, tpm_buf, READ_PUBEK_RESULT_MIN_BODY_SIZE,
"attempting to read the PUBEK"))
- goto out_buf;
+ goto out_ops;
- out = (struct tpm_readpubek_out *)&tpm_buf.data[10];
+ out = (struct tpm_readpubek_out *)&tpm_buf->data[10];
str +=
sprintf(str,
"Algorithm: %4ph\n"
@@ -71,8 +73,6 @@ static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
for (i = 0; i < 256; i += 16)
str += sprintf(str, "%16ph\n", &out->modulus[i]);
-out_buf:
- tpm_buf_destroy(&tpm_buf);
out_ops:
tpm_put_ops(chip);
return str - buf;
diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c
index cf64c7385105..974894013287 100644
--- a/drivers/char/tpm/tpm1-cmd.c
+++ b/drivers/char/tpm/tpm1-cmd.c
@@ -323,19 +323,19 @@ unsigned long tpm1_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
*/
static int tpm1_startup(struct tpm_chip *chip)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
int rc;
- dev_info(&chip->dev, "starting up the TPM manually\n");
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_STARTUP);
- if (rc < 0)
- return rc;
+ dev_info(&chip->dev, "starting up the TPM manually\n");
- tpm_buf_append_u16(&buf, TPM_ST_CLEAR);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_STARTUP);
+ tpm_buf_append_u16(buf, TPM_ST_CLEAR);
- rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to start the TPM");
- tpm_buf_destroy(&buf);
+ rc = tpm_transmit_cmd(chip, buf, 0, "attempting to start the TPM");
return rc;
}
@@ -463,18 +463,18 @@ int tpm1_get_timeouts(struct tpm_chip *chip)
int tpm1_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash,
const char *log_msg)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
int rc;
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCR_EXTEND);
- if (rc)
- return rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
- tpm_buf_append_u32(&buf, pcr_idx);
- tpm_buf_append(&buf, hash, TPM_DIGEST_SIZE);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCR_EXTEND);
+ tpm_buf_append_u32(buf, pcr_idx);
+ tpm_buf_append(buf, hash, TPM_DIGEST_SIZE);
- rc = tpm_transmit_cmd(chip, &buf, TPM_DIGEST_SIZE, log_msg);
- tpm_buf_destroy(&buf);
+ rc = tpm_transmit_cmd(chip, buf, TPM_DIGEST_SIZE, log_msg);
return rc;
}
@@ -482,31 +482,32 @@ int tpm1_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash,
ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
const char *desc, size_t min_cap_length)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
int rc;
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_CAP);
- if (rc)
- return rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_CAP);
if (subcap_id == TPM_CAP_VERSION_1_1 ||
subcap_id == TPM_CAP_VERSION_1_2) {
- tpm_buf_append_u32(&buf, subcap_id);
- tpm_buf_append_u32(&buf, 0);
+ tpm_buf_append_u32(buf, subcap_id);
+ tpm_buf_append_u32(buf, 0);
} else {
if (subcap_id == TPM_CAP_FLAG_PERM ||
subcap_id == TPM_CAP_FLAG_VOL)
- tpm_buf_append_u32(&buf, TPM_CAP_FLAG);
+ tpm_buf_append_u32(buf, TPM_CAP_FLAG);
else
- tpm_buf_append_u32(&buf, TPM_CAP_PROP);
+ tpm_buf_append_u32(buf, TPM_CAP_PROP);
- tpm_buf_append_u32(&buf, 4);
- tpm_buf_append_u32(&buf, subcap_id);
+ tpm_buf_append_u32(buf, 4);
+ tpm_buf_append_u32(buf, subcap_id);
}
- rc = tpm_transmit_cmd(chip, &buf, min_cap_length, desc);
+ rc = tpm_transmit_cmd(chip, buf, min_cap_length, desc);
if (!rc)
- *cap = *(cap_t *)&buf.data[TPM_HEADER_SIZE + 4];
- tpm_buf_destroy(&buf);
+ *cap = *(cap_t *)&buf->data[TPM_HEADER_SIZE + 4];
return rc;
}
EXPORT_SYMBOL_GPL(tpm1_getcap);
@@ -529,83 +530,76 @@ struct tpm1_get_random_out {
*/
int tpm1_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
{
+ struct tpm_buf *buf __free(kfree) = NULL;
struct tpm1_get_random_out *out;
u32 num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
- struct tpm_buf buf;
u32 total = 0;
int retries = 5;
u32 recd;
int rc;
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_RANDOM);
- if (rc)
- return rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_RANDOM);
do {
- tpm_buf_append_u32(&buf, num_bytes);
+ tpm_buf_append_u32(buf, num_bytes);
- rc = tpm_transmit_cmd(chip, &buf, sizeof(out->rng_data_len),
+ rc = tpm_transmit_cmd(chip, buf, sizeof(out->rng_data_len),
"attempting get random");
if (rc) {
if (rc > 0)
rc = -EIO;
- goto out;
+ return rc;
}
- out = (struct tpm1_get_random_out *)&buf.data[TPM_HEADER_SIZE];
+ out = (struct tpm1_get_random_out *)&buf->data[TPM_HEADER_SIZE];
recd = be32_to_cpu(out->rng_data_len);
- if (recd > num_bytes) {
- rc = -EFAULT;
- goto out;
- }
+ if (recd > num_bytes)
+ return -EFAULT;
+
+ if (buf->length < TPM_HEADER_SIZE +
+ sizeof(out->rng_data_len) + recd)
+ return -EFAULT;
- if (tpm_buf_length(&buf) < TPM_HEADER_SIZE +
- sizeof(out->rng_data_len) + recd) {
- rc = -EFAULT;
- goto out;
- }
memcpy(dest, out->rng_data, recd);
dest += recd;
total += recd;
num_bytes -= recd;
- tpm_buf_reset(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_RANDOM);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_RANDOM);
} while (retries-- && total < max);
rc = total ? (int)total : -EIO;
-out:
- tpm_buf_destroy(&buf);
return rc;
}
#define TPM_ORD_PCRREAD 21
int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
int rc;
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCRREAD);
- if (rc)
- return rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
- tpm_buf_append_u32(&buf, pcr_idx);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCRREAD);
+ tpm_buf_append_u32(buf, pcr_idx);
- rc = tpm_transmit_cmd(chip, &buf, TPM_DIGEST_SIZE,
+ rc = tpm_transmit_cmd(chip, buf, TPM_DIGEST_SIZE,
"attempting to read a pcr value");
if (rc)
- goto out;
-
- if (tpm_buf_length(&buf) < TPM_DIGEST_SIZE) {
- rc = -EFAULT;
- goto out;
- }
+ return rc;
- memcpy(res_buf, &buf.data[TPM_HEADER_SIZE], TPM_DIGEST_SIZE);
+ if (buf->length < TPM_DIGEST_SIZE)
+ return -EFAULT;
-out:
- tpm_buf_destroy(&buf);
+ memcpy(res_buf, &buf->data[TPM_HEADER_SIZE], TPM_DIGEST_SIZE);
return rc;
}
@@ -619,15 +613,15 @@ int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
*/
static int tpm1_continue_selftest(struct tpm_chip *chip)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
int rc;
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_CONTINUE_SELFTEST);
- if (rc)
- return rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
- rc = tpm_transmit_cmd(chip, &buf, 0, "continue selftest");
- tpm_buf_destroy(&buf);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_CONTINUE_SELFTEST);
+ rc = tpm_transmit_cmd(chip, buf, 0, "continue selftest");
return rc;
}
@@ -741,23 +735,25 @@ int tpm1_auto_startup(struct tpm_chip *chip)
*/
int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr)
{
+ struct tpm_buf *buf __free(kfree) = NULL;
u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
- struct tpm_buf buf;
unsigned int try;
int rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
/* for buggy tpm, flush pcrs with extend to selected dummy */
if (tpm_suspend_pcr)
rc = tpm1_pcr_extend(chip, tpm_suspend_pcr, dummy_hash,
"extending dummy pcr before suspend");
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SAVESTATE);
- if (rc)
- return rc;
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SAVESTATE);
+
/* now do the actual savestate */
for (try = 0; try < TPM_RETRY; try++) {
- rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
+ rc = tpm_transmit_cmd(chip, buf, 0, NULL);
/*
* If the TPM indicates that it is too busy to respond to
* this command then retry before giving up. It can take
@@ -772,7 +768,7 @@ int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr)
break;
tpm_msleep(TPM_TIMEOUT_RETRY);
- tpm_buf_reset(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SAVESTATE);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SAVESTATE);
}
if (rc)
@@ -782,8 +778,6 @@ int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr)
dev_warn(&chip->dev, "TPM savestate took %dms\n",
try * TPM_TIMEOUT_RETRY);
- tpm_buf_destroy(&buf);
-
return rc;
}
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 524d802ede26..86b961f4027b 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -165,14 +165,18 @@ struct tpm2_pcr_read_out {
int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
struct tpm_digest *digest, u16 *digest_size_ptr)
{
+ struct tpm_buf *buf __free(kfree) = NULL;
int i;
int rc;
- struct tpm_buf buf;
struct tpm2_pcr_read_out *out;
u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0};
u16 digest_size;
u16 expected_digest_size = 0;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
if (pcr_idx >= TPM2_PLATFORM_PCR)
return -EINVAL;
@@ -187,23 +191,21 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
expected_digest_size = chip->allocated_banks[i].digest_size;
}
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
- if (rc)
- return rc;
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
- tpm_buf_append_u32(&buf, 1);
- tpm_buf_append_u16(&buf, digest->alg_id);
- tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN);
- tpm_buf_append(&buf, (const unsigned char *)pcr_select,
+ tpm_buf_append_u32(buf, 1);
+ tpm_buf_append_u16(buf, digest->alg_id);
+ tpm_buf_append_u8(buf, TPM2_PCR_SELECT_MIN);
+ tpm_buf_append(buf, (const unsigned char *)pcr_select,
sizeof(pcr_select));
- rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to read a pcr value");
+ rc = tpm_transmit_cmd(chip, buf, 0, "attempting to read a pcr value");
if (rc)
goto out;
- out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
+ out = (struct tpm2_pcr_read_out *)&buf->data[TPM_HEADER_SIZE];
digest_size = be16_to_cpu(out->digest_size);
if (digest_size > sizeof(digest->digest) ||
(!digest_size_ptr && digest_size != expected_digest_size)) {
@@ -216,7 +218,6 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
memcpy(digest->digest, out->digest, digest_size);
out:
- tpm_buf_destroy(&buf);
return rc;
}
@@ -232,46 +233,43 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
struct tpm_digest *digests)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
int rc;
int i;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
if (!disable_pcr_integrity) {
rc = tpm2_start_auth_session(chip);
if (rc)
return rc;
}
- rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
- if (rc) {
- if (!disable_pcr_integrity)
- tpm2_end_auth_session(chip);
- return rc;
- }
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
if (!disable_pcr_integrity) {
- tpm_buf_append_name(chip, &buf, pcr_idx, NULL);
- tpm_buf_append_hmac_session(chip, &buf, 0, NULL, 0);
+ tpm_buf_append_name(chip, buf, pcr_idx, NULL);
+ tpm_buf_append_hmac_session(chip, buf, 0, NULL, 0);
} else {
- tpm_buf_append_handle(chip, &buf, pcr_idx);
- tpm_buf_append_auth(chip, &buf, 0, NULL, 0);
+ tpm_buf_append_handle(chip, buf, pcr_idx);
+ tpm_buf_append_auth(chip, buf, 0, NULL, 0);
}
- tpm_buf_append_u32(&buf, chip->nr_allocated_banks);
+ tpm_buf_append_u32(buf, chip->nr_allocated_banks);
for (i = 0; i < chip->nr_allocated_banks; i++) {
- tpm_buf_append_u16(&buf, digests[i].alg_id);
- tpm_buf_append(&buf, (const unsigned char *)&digests[i].digest,
+ tpm_buf_append_u16(buf, digests[i].alg_id);
+ tpm_buf_append(buf, (const unsigned char *)&digests[i].digest,
chip->allocated_banks[i].digest_size);
}
if (!disable_pcr_integrity)
- tpm_buf_fill_hmac_session(chip, &buf);
- rc = tpm_transmit_cmd(chip, &buf, 0, "attempting extend a PCR value");
+ tpm_buf_fill_hmac_session(chip, buf);
+ rc = tpm_transmit_cmd(chip, buf, 0, "attempting extend a PCR value");
if (!disable_pcr_integrity)
- rc = tpm_buf_check_hmac_response(chip, &buf, rc);
-
- tpm_buf_destroy(&buf);
+ rc = tpm_buf_check_hmac_response(chip, buf, rc);
return rc;
}
@@ -294,9 +292,9 @@ struct tpm2_get_random_out {
*/
int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
{
+ struct tpm_buf *buf __free(kfree) = NULL;
struct tpm2_get_random_out *out;
struct tpm_header *head;
- struct tpm_buf buf;
u32 recd;
u32 num_bytes = max;
int err;
@@ -308,43 +306,41 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
if (!num_bytes || max > TPM_MAX_RNG_DATA)
return -EINVAL;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
err = tpm2_start_auth_session(chip);
if (err)
return err;
- err = tpm_buf_init(&buf, 0, 0);
- if (err) {
- tpm2_end_auth_session(chip);
- return err;
- }
-
do {
- tpm_buf_reset(&buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
- tpm_buf_append_hmac_session_opt(chip, &buf, TPM2_SA_ENCRYPT
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
+ tpm_buf_append_hmac_session_opt(chip, buf, TPM2_SA_ENCRYPT
| TPM2_SA_CONTINUE_SESSION,
NULL, 0);
- tpm_buf_append_u16(&buf, num_bytes);
- tpm_buf_fill_hmac_session(chip, &buf);
- err = tpm_transmit_cmd(chip, &buf,
+ tpm_buf_append_u16(buf, num_bytes);
+ tpm_buf_fill_hmac_session(chip, buf);
+ err = tpm_transmit_cmd(chip, buf,
offsetof(struct tpm2_get_random_out,
buffer),
"attempting get random");
- err = tpm_buf_check_hmac_response(chip, &buf, err);
+ err = tpm_buf_check_hmac_response(chip, buf, err);
if (err) {
if (err > 0)
err = -EIO;
goto out;
}
- head = (struct tpm_header *)buf.data;
+ head = (struct tpm_header *)buf->data;
offset = TPM_HEADER_SIZE;
/* Skip the parameter size field: */
if (be16_to_cpu(head->tag) == TPM2_ST_SESSIONS)
offset += 4;
- out = (struct tpm2_get_random_out *)&buf.data[offset];
+ out = (struct tpm2_get_random_out *)&buf->data[offset];
recd = min_t(u32, be16_to_cpu(out->size), num_bytes);
- if (tpm_buf_length(&buf) <
+ if (tpm_buf_length(buf) <
TPM_HEADER_SIZE +
offsetof(struct tpm2_get_random_out, buffer) +
recd) {
@@ -358,11 +354,9 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
num_bytes -= recd;
} while (retries-- && total < max);
- tpm_buf_destroy(&buf);
-
return total ? total : -EIO;
+
out:
- tpm_buf_destroy(&buf);
tpm2_end_auth_session(chip);
return err;
}
@@ -374,20 +368,19 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
*/
void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
{
- struct tpm_buf buf;
- int rc;
+ struct tpm_buf *buf __free(kfree) = NULL;
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
- if (rc) {
+ buf = tpm_buf_alloc();
+ if (!buf) {
dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
handle);
return;
}
- tpm_buf_append_u32(&buf, handle);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
+ tpm_buf_append_u32(buf, handle);
- tpm_transmit_cmd(chip, &buf, 0, "flushing context");
- tpm_buf_destroy(&buf);
+ tpm_transmit_cmd(chip, buf, 0, "flushing context");
}
EXPORT_SYMBOL_GPL(tpm2_flush_context);
@@ -413,20 +406,22 @@ struct tpm2_get_cap_out {
ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value,
const char *desc)
{
+ struct tpm_buf *buf __free(kfree) = NULL;
struct tpm2_get_cap_out *out;
- struct tpm_buf buf;
int rc;
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
- if (rc)
- return rc;
- tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
- tpm_buf_append_u32(&buf, property_id);
- tpm_buf_append_u32(&buf, 1);
- rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
+ tpm_buf_append_u32(buf, TPM2_CAP_TPM_PROPERTIES);
+ tpm_buf_append_u32(buf, property_id);
+ tpm_buf_append_u32(buf, 1);
+ rc = tpm_transmit_cmd(chip, buf, 0, NULL);
if (!rc) {
out = (struct tpm2_get_cap_out *)
- &buf.data[TPM_HEADER_SIZE];
+ &buf->data[TPM_HEADER_SIZE];
/*
* To prevent failing boot up of some systems, Infineon TPM2.0
* returns SUCCESS on TPM2_Startup in field upgrade mode. Also
@@ -438,7 +433,6 @@ ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value,
else
rc = -ENODATA;
}
- tpm_buf_destroy(&buf);
return rc;
}
EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
@@ -455,15 +449,15 @@ EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
*/
void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
{
- struct tpm_buf buf;
- int rc;
+ struct tpm_buf *buf __free(kfree) = NULL;
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SHUTDOWN);
- if (rc)
+ buf = tpm_buf_alloc();
+ if (!buf)
return;
- tpm_buf_append_u16(&buf, shutdown_type);
- tpm_transmit_cmd(chip, &buf, 0, "stopping the TPM");
- tpm_buf_destroy(&buf);
+
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SHUTDOWN);
+ tpm_buf_append_u16(buf, shutdown_type);
+ tpm_transmit_cmd(chip, buf, 0, "stopping the TPM");
}
/**
@@ -481,19 +475,19 @@ void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
*/
static int tpm2_do_selftest(struct tpm_chip *chip)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
int full;
int rc;
- for (full = 0; full < 2; full++) {
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST);
- if (rc)
- return rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
- tpm_buf_append_u8(&buf, full);
- rc = tpm_transmit_cmd(chip, &buf, 0,
+ for (full = 0; full < 2; full++) {
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_SELF_TEST);
+ tpm_buf_append_u8(buf, full);
+ rc = tpm_transmit_cmd(chip, buf, 0,
"attempting the self test");
- tpm_buf_destroy(&buf);
if (rc == TPM2_RC_TESTING)
rc = TPM2_RC_SUCCESS;
@@ -518,24 +512,25 @@ static int tpm2_do_selftest(struct tpm_chip *chip)
*/
int tpm2_probe(struct tpm_chip *chip)
{
+ struct tpm_buf *buf __free(kfree) = NULL;
struct tpm_header *out;
- struct tpm_buf buf;
int rc;
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
- if (rc)
- return rc;
- tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
- tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
- tpm_buf_append_u32(&buf, 1);
- rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
+ tpm_buf_append_u32(buf, TPM2_CAP_TPM_PROPERTIES);
+ tpm_buf_append_u32(buf, TPM_PT_TOTAL_COMMANDS);
+ tpm_buf_append_u32(buf, 1);
+ rc = tpm_transmit_cmd(chip, buf, 0, NULL);
/* We ignore TPM return codes on purpose. */
if (rc >= 0) {
- out = (struct tpm_header *)buf.data;
+ out = (struct tpm_header *)buf->data;
if (be16_to_cpu(out->tag) == TPM2_ST_NO_SESSIONS)
chip->flags |= TPM_CHIP_FLAG_TPM2;
}
- tpm_buf_destroy(&buf);
return 0;
}
EXPORT_SYMBOL_GPL(tpm2_probe);
@@ -574,8 +569,8 @@ struct tpm2_pcr_selection {
ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
{
+ struct tpm_buf *buf __free(kfree) = NULL;
struct tpm2_pcr_selection pcr_selection;
- struct tpm_buf buf;
void *marker;
void *end;
void *pcr_select_offset;
@@ -587,41 +582,39 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
int rc;
int i = 0;
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
- if (rc)
- return rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
- tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
- tpm_buf_append_u32(&buf, 0);
- tpm_buf_append_u32(&buf, 1);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
+ tpm_buf_append_u32(buf, TPM2_CAP_PCRS);
+ tpm_buf_append_u32(buf, 0);
+ tpm_buf_append_u32(buf, 1);
- rc = tpm_transmit_cmd(chip, &buf, 9, "get tpm pcr allocation");
+ rc = tpm_transmit_cmd(chip, buf, 9, "get tpm pcr allocation");
if (rc)
- goto out;
+ return rc;
nr_possible_banks = be32_to_cpup(
- (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
+ (__be32 *)&buf->data[TPM_HEADER_SIZE + 5]);
chip->allocated_banks = kcalloc(nr_possible_banks,
sizeof(*chip->allocated_banks),
GFP_KERNEL);
- if (!chip->allocated_banks) {
- rc = -ENOMEM;
- goto out;
- }
+ if (!chip->allocated_banks)
+ return -ENOMEM;
- marker = &buf.data[TPM_HEADER_SIZE + 9];
+ marker = &buf->data[TPM_HEADER_SIZE + 9];
- rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
- end = &buf.data[rsp_len];
+ rsp_len = be32_to_cpup((__be32 *)&buf->data[2]);
+ end = &buf->data[rsp_len];
+ return rc;
for (i = 0; i < nr_possible_banks; i++) {
pcr_select_offset = marker +
offsetof(struct tpm2_pcr_selection, size_of_select);
- if (pcr_select_offset >= end) {
- rc = -EFAULT;
- break;
- }
+ if (pcr_select_offset >= end)
+ return -EFAULT;
memcpy(&pcr_selection, marker, sizeof(pcr_selection));
hash_alg = be16_to_cpu(pcr_selection.hash_alg);
@@ -633,7 +626,7 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
rc = tpm2_init_bank_info(chip, nr_alloc_banks);
if (rc < 0)
- break;
+ return rc;
nr_alloc_banks++;
}
@@ -645,21 +638,22 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
}
chip->nr_allocated_banks = nr_alloc_banks;
-out:
- tpm_buf_destroy(&buf);
-
- return rc;
+ return 0;
}
int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
u32 nr_commands;
__be32 *attrs;
u32 cc;
int i;
int rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
rc = tpm2_get_tpm_pt(chip, TPM_PT_TOTAL_COMMANDS, &nr_commands, NULL);
if (rc)
goto out;
@@ -676,30 +670,24 @@ int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
goto out;
}
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
- if (rc)
- goto out;
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
+ tpm_buf_append_u32(buf, TPM2_CAP_COMMANDS);
+ tpm_buf_append_u32(buf, TPM2_CC_FIRST);
+ tpm_buf_append_u32(buf, nr_commands);
- tpm_buf_append_u32(&buf, TPM2_CAP_COMMANDS);
- tpm_buf_append_u32(&buf, TPM2_CC_FIRST);
- tpm_buf_append_u32(&buf, nr_commands);
-
- rc = tpm_transmit_cmd(chip, &buf, 9 + 4 * nr_commands, NULL);
- if (rc) {
- tpm_buf_destroy(&buf);
+ rc = tpm_transmit_cmd(chip, buf, 9 + 4 * nr_commands, NULL);
+ if (rc)
goto out;
- }
if (nr_commands !=
- be32_to_cpup((__be32 *)&buf.data[TPM_HEADER_SIZE + 5])) {
+ be32_to_cpup((__be32 *)&buf->data[TPM_HEADER_SIZE + 5])) {
rc = -EFAULT;
- tpm_buf_destroy(&buf);
goto out;
}
chip->nr_commands = nr_commands;
- attrs = (__be32 *)&buf.data[TPM_HEADER_SIZE + 9];
+ attrs = (__be32 *)&buf->data[TPM_HEADER_SIZE + 9];
for (i = 0; i < nr_commands; i++, attrs++) {
chip->cc_attrs_tbl[i] = be32_to_cpup(attrs);
cc = chip->cc_attrs_tbl[i] & 0xFFFF;
@@ -711,8 +699,6 @@ int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip)
}
}
- tpm_buf_destroy(&buf);
-
out:
if (rc > 0)
rc = -ENODEV;
@@ -733,20 +719,18 @@ EXPORT_SYMBOL_GPL(tpm2_get_cc_attrs_tbl);
static int tpm2_startup(struct tpm_chip *chip)
{
- struct tpm_buf buf;
- int rc;
+ struct tpm_buf *buf __free(kfree) = NULL;
- dev_info(&chip->dev, "starting up the TPM manually\n");
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_STARTUP);
- if (rc < 0)
- return rc;
+ dev_info(&chip->dev, "starting up the TPM manually\n");
- tpm_buf_append_u16(&buf, TPM2_SU_CLEAR);
- rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to start the TPM");
- tpm_buf_destroy(&buf);
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_STARTUP);
+ tpm_buf_append_u16(buf, TPM2_SU_CLEAR);
- return rc;
+ return tpm_transmit_cmd(chip, buf, 0, "attempting to start the TPM");
}
/**
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index 7b5049b3d476..50c481c7c947 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -182,19 +182,18 @@ static int tpm2_parse_read_public(char *name, struct tpm_buf *buf)
static int tpm2_read_public(struct tpm_chip *chip, u32 handle, char *name)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
int rc;
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_READ_PUBLIC);
- if (rc)
- return rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
- tpm_buf_append_u32(&buf, handle);
- rc = tpm_transmit_cmd(chip, &buf, 0, "read public");
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_READ_PUBLIC);
+ tpm_buf_append_u32(buf, handle);
+ rc = tpm_transmit_cmd(chip, buf, 0, "read public");
if (rc == TPM2_RC_SUCCESS)
- rc = tpm2_parse_read_public(name, &buf);
-
- tpm_buf_destroy(&buf);
+ rc = tpm2_parse_read_public(name, buf);
return rc;
}
@@ -968,8 +967,8 @@ static int tpm2_load_null(struct tpm_chip *chip, u32 *null_key)
*/
int tpm2_start_auth_session(struct tpm_chip *chip)
{
+ struct tpm_buf *buf __free(kfree) = NULL;
struct tpm2_auth *auth;
- struct tpm_buf buf;
u32 null_key;
int rc;
@@ -978,6 +977,10 @@ int tpm2_start_auth_session(struct tpm_chip *chip)
return 0;
}
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
auth = kzalloc(sizeof(*auth), GFP_KERNEL);
if (!auth)
return -ENOMEM;
@@ -988,41 +991,36 @@ int tpm2_start_auth_session(struct tpm_chip *chip)
auth->session = TPM_HEADER_SIZE;
- rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_START_AUTH_SESS);
- if (rc)
- goto out;
-
+ tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_START_AUTH_SESS);
/* salt key handle */
- tpm_buf_append_u32(&buf, null_key);
+ tpm_buf_append_u32(buf, null_key);
/* bind key handle */
- tpm_buf_append_u32(&buf, TPM2_RH_NULL);
+ tpm_buf_append_u32(buf, TPM2_RH_NULL);
/* nonce caller */
get_random_bytes(auth->our_nonce, sizeof(auth->our_nonce));
- tpm_buf_append_u16(&buf, sizeof(auth->our_nonce));
- tpm_buf_append(&buf, auth->our_nonce, sizeof(auth->our_nonce));
+ tpm_buf_append_u16(buf, sizeof(auth->our_nonce));
+ tpm_buf_append(buf, auth->our_nonce, sizeof(auth->our_nonce));
/* append encrypted salt and squirrel away unencrypted in auth */
- tpm_buf_append_salt(&buf, chip, auth);
+ tpm_buf_append_salt(buf, chip, auth);
/* session type (HMAC, audit or policy) */
- tpm_buf_append_u8(&buf, TPM2_SE_HMAC);
+ tpm_buf_append_u8(buf, TPM2_SE_HMAC);
/* symmetric encryption parameters */
/* symmetric algorithm */
- tpm_buf_append_u16(&buf, TPM_ALG_AES);
+ tpm_buf_append_u16(buf, TPM_ALG_AES);
/* bits for symmetric algorithm */
- tpm_buf_append_u16(&buf, AES_KEY_BITS);
+ tpm_buf_append_u16(buf, AES_KEY_BITS);
/* symmetric algorithm mode (must be CFB) */
- tpm_buf_append_u16(&buf, TPM_ALG_CFB);
+ tpm_buf_append_u16(buf, TPM_ALG_CFB);
/* hash algorithm for session */
- tpm_buf_append_u16(&buf, TPM_ALG_SHA256);
+ tpm_buf_append_u16(buf, TPM_ALG_SHA256);
- rc = tpm_ret_to_err(tpm_transmit_cmd(chip, &buf, 0, "StartAuthSession"));
+ rc = tpm_ret_to_err(tpm_transmit_cmd(chip, buf, 0, "StartAuthSession"));
tpm2_flush_context(chip, null_key);
if (rc == TPM2_RC_SUCCESS)
- rc = tpm2_parse_start_auth_session(auth, &buf);
-
- tpm_buf_destroy(&buf);
+ rc = tpm2_parse_start_auth_session(auth, buf);
if (rc == TPM2_RC_SUCCESS) {
chip->auth = auth;
@@ -1243,19 +1241,20 @@ static int tpm2_parse_create_primary(struct tpm_chip *chip, struct tpm_buf *buf,
static int tpm2_create_primary(struct tpm_chip *chip, u32 hierarchy,
u32 *handle, u8 *name)
{
+ struct tpm_buf *buf __free(kfree) = NULL;
+ struct tpm_buf *template __free(kfree) = NULL;
int rc;
- struct tpm_buf buf;
- struct tpm_buf template;
- rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE_PRIMARY);
- if (rc)
- return rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
- rc = tpm_buf_init_sized(&template);
- if (rc) {
- tpm_buf_destroy(&buf);
- return rc;
- }
+ template = tpm_buf_alloc();
+ if (!template)
+ return -ENOMEM;
+
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE_PRIMARY);
+ tpm_buf_reset_sized(template);
/*
* create the template. Note: in order for userspace to
@@ -1267,75 +1266,72 @@ static int tpm2_create_primary(struct tpm_chip *chip, u32 hierarchy,
*/
/* key type */
- tpm_buf_append_u16(&template, TPM_ALG_ECC);
+ tpm_buf_append_u16(template, TPM_ALG_ECC);
/* name algorithm */
- tpm_buf_append_u16(&template, TPM_ALG_SHA256);
+ tpm_buf_append_u16(template, TPM_ALG_SHA256);
/* object properties */
- tpm_buf_append_u32(&template, TPM2_OA_NULL_KEY);
+ tpm_buf_append_u32(template, TPM2_OA_NULL_KEY);
/* sauth policy (empty) */
- tpm_buf_append_u16(&template, 0);
+ tpm_buf_append_u16(template, 0);
/* BEGIN parameters: key specific; for ECC*/
/* symmetric algorithm */
- tpm_buf_append_u16(&template, TPM_ALG_AES);
+ tpm_buf_append_u16(template, TPM_ALG_AES);
/* bits for symmetric algorithm */
- tpm_buf_append_u16(&template, AES_KEY_BITS);
+ tpm_buf_append_u16(template, AES_KEY_BITS);
/* algorithm mode (must be CFB) */
- tpm_buf_append_u16(&template, TPM_ALG_CFB);
+ tpm_buf_append_u16(template, TPM_ALG_CFB);
/* scheme (NULL means any scheme) */
- tpm_buf_append_u16(&template, TPM_ALG_NULL);
+ tpm_buf_append_u16(template, TPM_ALG_NULL);
/* ECC Curve ID */
- tpm_buf_append_u16(&template, TPM2_ECC_NIST_P256);
+ tpm_buf_append_u16(template, TPM2_ECC_NIST_P256);
/* KDF Scheme */
- tpm_buf_append_u16(&template, TPM_ALG_NULL);
+ tpm_buf_append_u16(template, TPM_ALG_NULL);
/* unique: key specific; for ECC it is two zero size points */
- tpm_buf_append_u16(&template, 0);
- tpm_buf_append_u16(&template, 0);
+ tpm_buf_append_u16(template, 0);
+ tpm_buf_append_u16(template, 0);
/* END parameters */
/* primary handle */
- tpm_buf_append_u32(&buf, hierarchy);
- tpm_buf_append_empty_auth(&buf, TPM2_RS_PW);
+ tpm_buf_append_u32(buf, hierarchy);
+ tpm_buf_append_empty_auth(buf, TPM2_RS_PW);
/* sensitive create size is 4 for two empty buffers */
- tpm_buf_append_u16(&buf, 4);
+ tpm_buf_append_u16(buf, 4);
/* sensitive create auth data (empty) */
- tpm_buf_append_u16(&buf, 0);
+ tpm_buf_append_u16(buf, 0);
/* sensitive create sensitive data (empty) */
- tpm_buf_append_u16(&buf, 0);
+ tpm_buf_append_u16(buf, 0);
/* the public template */
- tpm_buf_append(&buf, template.data, template.length);
- tpm_buf_destroy(&template);
+ tpm_buf_append(buf, template->data, template->length);
/* outside info (empty) */
- tpm_buf_append_u16(&buf, 0);
+ tpm_buf_append_u16(buf, 0);
/* creation PCR (none) */
- tpm_buf_append_u32(&buf, 0);
+ tpm_buf_append_u32(buf, 0);
- rc = tpm_transmit_cmd(chip, &buf, 0,
+ rc = tpm_transmit_cmd(chip, buf, 0,
"attempting to create NULL primary");
if (rc == TPM2_RC_SUCCESS)
- rc = tpm2_parse_create_primary(chip, &buf, handle, hierarchy,
+ rc = tpm2_parse_create_primary(chip, buf, handle, hierarchy,
name);
- tpm_buf_destroy(&buf);
-
return rc;
}
diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
index 60354cd53b5c..818b6f4084c7 100644
--- a/drivers/char/tpm/tpm2-space.c
+++ b/drivers/char/tpm/tpm2-space.c
@@ -71,24 +71,25 @@ void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space)
int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
unsigned int *offset, u32 *handle)
{
- struct tpm_buf tbuf;
+ struct tpm_buf *tbuf __free(kfree) = NULL;
struct tpm2_context *ctx;
unsigned int body_size;
int rc;
- rc = tpm_buf_init(&tbuf, TPM2_ST_NO_SESSIONS, TPM2_CC_CONTEXT_LOAD);
- if (rc)
- return rc;
+ tbuf = tpm_buf_alloc();
+ if (!tbuf)
+ return -ENOMEM;
+
+ tpm_buf_reset(tbuf, TPM2_ST_NO_SESSIONS, TPM2_CC_CONTEXT_LOAD);
ctx = (struct tpm2_context *)&buf[*offset];
body_size = sizeof(*ctx) + be16_to_cpu(ctx->blob_size);
- tpm_buf_append(&tbuf, &buf[*offset], body_size);
+ tpm_buf_append(tbuf, &buf[*offset], body_size);
- rc = tpm_transmit_cmd(chip, &tbuf, 4, NULL);
+ rc = tpm_transmit_cmd(chip, tbuf, 4, NULL);
if (rc < 0) {
dev_warn(&chip->dev, "%s: failed with a system error %d\n",
__func__, rc);
- tpm_buf_destroy(&tbuf);
return -EFAULT;
} else if (tpm2_rc_value(rc) == TPM2_RC_HANDLE ||
rc == TPM2_RC_REFERENCE_H0) {
@@ -103,64 +104,55 @@ int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
* flushed outside the space
*/
*handle = 0;
- tpm_buf_destroy(&tbuf);
return -ENOENT;
} else if (tpm2_rc_value(rc) == TPM2_RC_INTEGRITY) {
- tpm_buf_destroy(&tbuf);
return -EINVAL;
} else if (rc > 0) {
dev_warn(&chip->dev, "%s: failed with a TPM error 0x%04X\n",
__func__, rc);
- tpm_buf_destroy(&tbuf);
return -EFAULT;
}
- *handle = be32_to_cpup((__be32 *)&tbuf.data[TPM_HEADER_SIZE]);
+ *handle = be32_to_cpup((__be32 *)&tbuf->data[TPM_HEADER_SIZE]);
*offset += body_size;
-
- tpm_buf_destroy(&tbuf);
return 0;
}
int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
unsigned int buf_size, unsigned int *offset)
{
- struct tpm_buf tbuf;
+ struct tpm_buf *tbuf __free(kfree) = NULL;
unsigned int body_size;
int rc;
- rc = tpm_buf_init(&tbuf, TPM2_ST_NO_SESSIONS, TPM2_CC_CONTEXT_SAVE);
- if (rc)
- return rc;
+ tbuf = tpm_buf_alloc();
+ if (!tbuf)
+ return -ENOMEM;
- tpm_buf_append_u32(&tbuf, handle);
+ tpm_buf_reset(tbuf, TPM2_ST_NO_SESSIONS, TPM2_CC_CONTEXT_SAVE);
+ tpm_buf_append_u32(tbuf, handle);
- rc = tpm_transmit_cmd(chip, &tbuf, 0, NULL);
+ rc = tpm_transmit_cmd(chip, tbuf, 0, NULL);
if (rc < 0) {
dev_warn(&chip->dev, "%s: failed with a system error %d\n",
__func__, rc);
- tpm_buf_destroy(&tbuf);
return -EFAULT;
} else if (tpm2_rc_value(rc) == TPM2_RC_REFERENCE_H0) {
- tpm_buf_destroy(&tbuf);
return -ENOENT;
} else if (rc) {
dev_warn(&chip->dev, "%s: failed with a TPM error 0x%04X\n",
__func__, rc);
- tpm_buf_destroy(&tbuf);
return -EFAULT;
}
- body_size = tpm_buf_length(&tbuf) - TPM_HEADER_SIZE;
+ body_size = tpm_buf_length(tbuf) - TPM_HEADER_SIZE;
if ((*offset + body_size) > buf_size) {
dev_warn(&chip->dev, "%s: out of backing storage\n", __func__);
- tpm_buf_destroy(&tbuf);
return -ENOMEM;
}
- memcpy(&buf[*offset], &tbuf.data[TPM_HEADER_SIZE], body_size);
+ memcpy(&buf[*offset], &tbuf->data[TPM_HEADER_SIZE], body_size);
*offset += body_size;
- tpm_buf_destroy(&tbuf);
return 0;
}
diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c b/drivers/char/tpm/tpm_vtpm_proxy.c
index 0818bb517805..6d76fe28826a 100644
--- a/drivers/char/tpm/tpm_vtpm_proxy.c
+++ b/drivers/char/tpm/tpm_vtpm_proxy.c
@@ -395,40 +395,36 @@ static bool vtpm_proxy_tpm_req_canceled(struct tpm_chip *chip, u8 status)
static int vtpm_proxy_request_locality(struct tpm_chip *chip, int locality)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
int rc;
const struct tpm_header *header;
struct proxy_dev *proxy_dev = dev_get_drvdata(&chip->dev);
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
if (chip->flags & TPM_CHIP_FLAG_TPM2)
- rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS,
- TPM2_CC_SET_LOCALITY);
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_SET_LOCALITY);
else
- rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND,
- TPM_ORD_SET_LOCALITY);
- if (rc)
- return rc;
- tpm_buf_append_u8(&buf, locality);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SET_LOCALITY);
+
+ tpm_buf_append_u8(buf, locality);
proxy_dev->state |= STATE_DRIVER_COMMAND;
- rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to set locality");
+ rc = tpm_transmit_cmd(chip, buf, 0, "attempting to set locality");
proxy_dev->state &= ~STATE_DRIVER_COMMAND;
- if (rc < 0) {
- locality = rc;
- goto out;
- }
+ if (rc < 0)
+ return rc;
- header = (const struct tpm_header *)buf.data;
+ header = (const struct tpm_header *)buf->data;
rc = be32_to_cpu(header->return_code);
if (rc)
locality = -1;
-out:
- tpm_buf_destroy(&buf);
-
return locality;
}
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 804fbbe3873d..7f237b5ac8c2 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -375,13 +375,14 @@ enum tpm_buf_flags {
};
/*
- * A string buffer type for constructing TPM commands.
+ * A buffer for constructing and parsing TPM commands, responses and sized
+ * (TPM2B) buffers.
*/
struct tpm_buf {
- u32 flags;
- u32 length;
- u8 *data;
- u8 handles;
+ u16 flags;
+ u16 length;
+ u16 handles;
+ u8 data[];
};
enum tpm2_object_attributes {
@@ -412,11 +413,25 @@ struct tpm2_hash {
unsigned int tpm_id;
};
-int tpm_buf_init(struct tpm_buf *buf, u16 tag, u32 ordinal);
+/**
+ * tpm_buf_alloc() - Allocates a buffer for reading and writing TPM binary data
+ *
+ * Allocates %PAGE_SIZE of memory and places &tpm_buf to the beginning of the
+ * allocated buffer. For that reason the total capacity can be at most 4090
+ * bytes. If a caller tries to surpass the maximum capacity, %TPM_BUF_OVERFLOW
+ * will be set and any future operations will be ignored.
+ *
+ * Return:
+ * * &tpm_buf: success
+ * * NULL: out of memory
+ */
+static inline struct tpm_buf *tpm_buf_alloc(void)
+{
+ return kzalloc(PAGE_SIZE, GFP_KERNEL);
+}
+
void tpm_buf_reset(struct tpm_buf *buf, u16 tag, u32 ordinal);
-int tpm_buf_init_sized(struct tpm_buf *buf);
void tpm_buf_reset_sized(struct tpm_buf *buf);
-void tpm_buf_destroy(struct tpm_buf *buf);
u32 tpm_buf_length(struct tpm_buf *buf);
void tpm_buf_append(struct tpm_buf *buf, const u8 *new_data, u16 new_length);
void tpm_buf_append_u8(struct tpm_buf *buf, const u8 value);
diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c
index 89c9798d1800..106496c68625 100644
--- a/security/keys/trusted-keys/trusted_tpm1.c
+++ b/security/keys/trusted-keys/trusted_tpm1.c
@@ -356,21 +356,24 @@ static int TSS_checkhmac2(unsigned char *buffer,
*/
int trusted_tpm_send(unsigned char *cmd, size_t buflen)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
int rc;
if (!chip)
return -ENODEV;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
rc = tpm_try_get_ops(chip);
if (rc)
return rc;
- buf.flags = 0;
- buf.length = buflen;
- buf.data = cmd;
+ tpm_buf_append(buf, cmd, buflen);
+
dump_tpm_buf(cmd);
- rc = tpm_transmit_cmd(chip, &buf, 4, "sending data");
+ rc = tpm_transmit_cmd(chip, buf, 4, "sending data");
dump_tpm_buf(cmd);
if (rc > 0)
@@ -672,23 +675,22 @@ static int tpm_unseal(struct tpm_buf *tb,
static int key_seal(struct trusted_key_payload *p,
struct trusted_key_options *o)
{
- struct tpm_buf tb;
+ struct tpm_buf *tb __free(kfree) = NULL;
int ret;
- ret = tpm_buf_init(&tb, 0, 0);
- if (ret)
- return ret;
+ tb = tpm_buf_alloc();
+ if (!tb)
+ return -ENOMEM;
/* include migratable flag at end of sealed key */
p->key[p->key_len] = p->migratable;
- ret = tpm_seal(&tb, o->keytype, o->keyhandle, o->keyauth,
+ ret = tpm_seal(tb, o->keytype, o->keyhandle, o->keyauth,
p->key, p->key_len + 1, p->blob, &p->blob_len,
o->blobauth, o->pcrinfo, o->pcrinfo_len);
if (ret < 0)
pr_info("srkseal failed (%d)\n", ret);
- tpm_buf_destroy(&tb);
return ret;
}
@@ -698,14 +700,14 @@ static int key_seal(struct trusted_key_payload *p,
static int key_unseal(struct trusted_key_payload *p,
struct trusted_key_options *o)
{
- struct tpm_buf tb;
+ struct tpm_buf *tb __free(kfree) = NULL;
int ret;
- ret = tpm_buf_init(&tb, 0, 0);
- if (ret)
- return ret;
+ tb = tpm_buf_alloc();
+ if (!tb)
+ return -ENOMEM;
- ret = tpm_unseal(&tb, o->keyhandle, o->keyauth, p->blob, p->blob_len,
+ ret = tpm_unseal(tb, o->keyhandle, o->keyauth, p->blob, p->blob_len,
o->blobauth, p->key, &p->key_len);
if (ret < 0)
pr_info("srkunseal failed (%d)\n", ret);
@@ -713,7 +715,6 @@ static int key_unseal(struct trusted_key_payload *p,
/* pull migratable flag out of sealed key */
p->migratable = p->key[--p->key_len];
- tpm_buf_destroy(&tb);
return ret;
}
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 024be262702f..54bcd8d0621e 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -241,14 +241,23 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options)
{
+ struct tpm_buf *buf __free(kfree) = NULL;
+ struct tpm_buf *sized __free(kfree) = NULL;
off_t offset = TPM_HEADER_SIZE;
- struct tpm_buf buf, sized;
int blob_len = 0;
u32 hash;
u32 flags;
int i;
int rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
+ sized = tpm_buf_alloc();
+ if (!sized)
+ return -ENOMEM;
+
for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
if (options->hash == tpm2_hash_map[i].crypto_id) {
hash = tpm2_hash_map[i].tpm_id;
@@ -270,89 +279,76 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
if (rc)
goto out_put;
- rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
- if (rc) {
- tpm2_end_auth_session(chip);
- goto out_put;
- }
-
- rc = tpm_buf_init_sized(&sized);
- if (rc) {
- tpm_buf_destroy(&buf);
- tpm2_end_auth_session(chip);
- goto out_put;
- }
-
- tpm_buf_append_name(chip, &buf, options->keyhandle, NULL);
- tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_DECRYPT,
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
+ tpm_buf_reset_sized(sized);
+ tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
+ tpm_buf_append_hmac_session(chip, buf, TPM2_SA_DECRYPT,
options->keyauth, TPM_DIGEST_SIZE);
/* sensitive */
- tpm_buf_append_u16(&sized, options->blobauth_len);
+ tpm_buf_append_u16(sized, options->blobauth_len);
if (options->blobauth_len)
- tpm_buf_append(&sized, options->blobauth, options->blobauth_len);
+ tpm_buf_append(sized, options->blobauth, options->blobauth_len);
- tpm_buf_append_u16(&sized, payload->key_len);
- tpm_buf_append(&sized, payload->key, payload->key_len);
- tpm_buf_append(&buf, sized.data, sized.length);
+ tpm_buf_append_u16(sized, payload->key_len);
+ tpm_buf_append(sized, payload->key, payload->key_len);
+ tpm_buf_append(buf, sized->data, sized->length);
/* public */
- tpm_buf_reset_sized(&sized);
- tpm_buf_append_u16(&sized, TPM_ALG_KEYEDHASH);
- tpm_buf_append_u16(&sized, hash);
+ tpm_buf_reset_sized(sized);
+ tpm_buf_append_u16(sized, TPM_ALG_KEYEDHASH);
+ tpm_buf_append_u16(sized, hash);
/* key properties */
flags = 0;
flags |= options->policydigest_len ? 0 : TPM2_OA_USER_WITH_AUTH;
flags |= payload->migratable ? 0 : (TPM2_OA_FIXED_TPM | TPM2_OA_FIXED_PARENT);
- tpm_buf_append_u32(&sized, flags);
+ tpm_buf_append_u32(sized, flags);
/* policy */
- tpm_buf_append_u16(&sized, options->policydigest_len);
+ tpm_buf_append_u16(sized, options->policydigest_len);
if (options->policydigest_len)
- tpm_buf_append(&sized, options->policydigest, options->policydigest_len);
+ tpm_buf_append(sized, options->policydigest, options->policydigest_len);
/* public parameters */
- tpm_buf_append_u16(&sized, TPM_ALG_NULL);
- tpm_buf_append_u16(&sized, 0);
+ tpm_buf_append_u16(sized, TPM_ALG_NULL);
+ tpm_buf_append_u16(sized, 0);
- tpm_buf_append(&buf, sized.data, sized.length);
+ tpm_buf_append(buf, sized->data, sized->length);
/* outside info */
- tpm_buf_append_u16(&buf, 0);
+ tpm_buf_append_u16(buf, 0);
/* creation PCR */
- tpm_buf_append_u32(&buf, 0);
+ tpm_buf_append_u32(buf, 0);
- if (buf.flags & TPM_BUF_OVERFLOW) {
+ if (buf->flags & TPM_BUF_OVERFLOW) {
rc = -E2BIG;
tpm2_end_auth_session(chip);
goto out;
}
- tpm_buf_fill_hmac_session(chip, &buf);
- rc = tpm_transmit_cmd(chip, &buf, 4, "sealing data");
- rc = tpm_buf_check_hmac_response(chip, &buf, rc);
+ tpm_buf_fill_hmac_session(chip, buf);
+ rc = tpm_transmit_cmd(chip, buf, 4, "sealing data");
+ rc = tpm_buf_check_hmac_response(chip, buf, rc);
if (rc)
goto out;
- blob_len = tpm_buf_read_u32(&buf, &offset);
- if (blob_len > MAX_BLOB_SIZE || buf.flags & TPM_BUF_BOUNDARY_ERROR) {
+ blob_len = tpm_buf_read_u32(buf, &offset);
+ if (blob_len > MAX_BLOB_SIZE || buf->flags & TPM_BUF_BOUNDARY_ERROR) {
rc = -E2BIG;
goto out;
}
- if (buf.length - offset < blob_len) {
+ if (buf->length - offset < blob_len) {
rc = -EFAULT;
goto out;
}
- blob_len = tpm2_key_encode(payload, options, &buf.data[offset], blob_len);
+ blob_len = tpm2_key_encode(payload, options, &buf->data[offset],
+ blob_len);
out:
- tpm_buf_destroy(&sized);
- tpm_buf_destroy(&buf);
-
if (rc > 0) {
if (tpm2_rc_value(rc) == TPM2_RC_HASH)
rc = -EINVAL;
@@ -387,7 +383,7 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
struct trusted_key_options *options,
u32 *blob_handle)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
unsigned int private_len;
unsigned int public_len;
unsigned int blob_len;
@@ -395,6 +391,10 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
int rc;
u32 attrs;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
rc = tpm2_key_decode(payload, options, &blob);
if (rc) {
/* old form */
@@ -438,35 +438,29 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
if (rc)
return rc;
- rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
- if (rc) {
- tpm2_end_auth_session(chip);
- return rc;
- }
-
- tpm_buf_append_name(chip, &buf, options->keyhandle, NULL);
- tpm_buf_append_hmac_session(chip, &buf, 0, options->keyauth,
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
+ tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
+ tpm_buf_append_hmac_session(chip, buf, 0, options->keyauth,
TPM_DIGEST_SIZE);
- tpm_buf_append(&buf, blob, blob_len);
+ tpm_buf_append(buf, blob, blob_len);
- if (buf.flags & TPM_BUF_OVERFLOW) {
+ if (buf->flags & TPM_BUF_OVERFLOW) {
rc = -E2BIG;
tpm2_end_auth_session(chip);
goto out;
}
- tpm_buf_fill_hmac_session(chip, &buf);
- rc = tpm_transmit_cmd(chip, &buf, 4, "loading blob");
- rc = tpm_buf_check_hmac_response(chip, &buf, rc);
+ tpm_buf_fill_hmac_session(chip, buf);
+ rc = tpm_transmit_cmd(chip, buf, 4, "loading blob");
+ rc = tpm_buf_check_hmac_response(chip, buf, rc);
if (!rc)
*blob_handle = be32_to_cpup(
- (__be32 *) &buf.data[TPM_HEADER_SIZE]);
+ (__be32 *)&buf->data[TPM_HEADER_SIZE]);
out:
if (blob != payload->blob)
kfree(blob);
- tpm_buf_destroy(&buf);
if (rc > 0)
rc = -EPERM;
@@ -491,25 +485,24 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
struct trusted_key_options *options,
u32 blob_handle)
{
- struct tpm_buf buf;
+ struct tpm_buf *buf __free(kfree) = NULL;
u16 data_len;
u8 *data;
int rc;
+ buf = tpm_buf_alloc();
+ if (!buf)
+ return -ENOMEM;
+
rc = tpm2_start_auth_session(chip);
if (rc)
return rc;
- rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
- if (rc) {
- tpm2_end_auth_session(chip);
- return rc;
- }
-
- tpm_buf_append_name(chip, &buf, blob_handle, NULL);
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
+ tpm_buf_append_name(chip, buf, blob_handle, NULL);
if (!options->policyhandle) {
- tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_ENCRYPT,
+ tpm_buf_append_hmac_session(chip, buf, TPM2_SA_ENCRYPT,
options->blobauth,
options->blobauth_len);
} else {
@@ -524,32 +517,28 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
* could repeat our actions with the exfiltrated
* password.
*/
- tpm2_buf_append_auth(&buf, options->policyhandle,
+ tpm2_buf_append_auth(buf, options->policyhandle,
NULL /* nonce */, 0, 0,
options->blobauth, options->blobauth_len);
- tpm_buf_append_hmac_session_opt(chip, &buf, TPM2_SA_ENCRYPT,
+ tpm_buf_append_hmac_session_opt(chip, buf, TPM2_SA_ENCRYPT,
NULL, 0);
}
- tpm_buf_fill_hmac_session(chip, &buf);
- rc = tpm_transmit_cmd(chip, &buf, 6, "unsealing");
- rc = tpm_buf_check_hmac_response(chip, &buf, rc);
+ tpm_buf_fill_hmac_session(chip, buf);
+ rc = tpm_transmit_cmd(chip, buf, 6, "unsealing");
+ rc = tpm_buf_check_hmac_response(chip, buf, rc);
if (rc > 0)
rc = -EPERM;
if (!rc) {
data_len = be16_to_cpup(
- (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
- if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE) {
- rc = -EFAULT;
- goto out;
- }
+ (__be16 *)&buf->data[TPM_HEADER_SIZE + 4]);
+ if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE)
+ return -EFAULT;
- if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 6 + data_len) {
- rc = -EFAULT;
- goto out;
- }
- data = &buf.data[TPM_HEADER_SIZE + 6];
+ if (tpm_buf_length(buf) < TPM_HEADER_SIZE + 6 + data_len)
+ return -EFAULT;
+ data = &buf->data[TPM_HEADER_SIZE + 6];
if (payload->old_format) {
/* migratable flag is at the end of the key */
@@ -566,8 +555,6 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
}
}
-out:
- tpm_buf_destroy(&buf);
return rc;
}
--
2.39.5
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH v4] tpm: Managed allocations for tpm_buf instances
2025-07-01 14:51 [PATCH v4] tpm: Managed allocations for tpm_buf instances Jarkko Sakkinen
@ 2025-07-01 21:42 ` Stefan Berger
2025-07-02 22:38 ` Jarkko Sakkinen
2025-07-02 2:51 ` James Bottomley
2025-07-02 12:57 ` Jason Gunthorpe
2 siblings, 1 reply; 7+ messages in thread
From: Stefan Berger @ 2025-07-01 21:42 UTC (permalink / raw)
To: Jarkko Sakkinen, linux-kernel
Cc: keyrings, Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe,
James Bottomley, Mimi Zohar, David Howells, Paul Moore,
James Morris, Serge E. Hallyn, open list:TPM DEVICE DRIVER,
open list:SECURITY SUBSYSTEM
On 7/1/25 10:51 AM, Jarkko Sakkinen wrote:
> From: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
>
> Repeal and replace tpm_buf_init() and tpm_buf_init_sized() with
> tpm_buf_alloc(), which returns a buffer of memory with the struct tpm_buf
> header at the beginning of the returned buffer. This leaves 4090 bytes of
> free space for the payload.
>
> Given that kfree() is now the destructor for struct tpm_buf instances,
> tpm_buf_destroy() becomes obsolete, and can be safely wiped of too.
s/of/off/ or s/wiped of/remove,/
>
> The actual gist is that now a tpm_buf can be now declared using
s/that now a/that a/
> __free(kfree) declared in linux/slab.h:
>
> struct tpm_buf *buf __free(kfree) = NULL;
>
> /* ... */
>
> buf = tpm_buf_alloc();
>
> Doing this has two-folded benefits:
>
> 1. Yet to be discoverd memory leaks in the pre-existing code base.
-> discovered
A couple of nits below and one stray 'return rc;' that should not be
there...
> 2. Memory leaks concerning new features and other contributions.
>
> In addition, the barrier to contribute is lowered given that managing
> memory is a factor easier.
>
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> index 524d802ede26..86b961f4027b 100644
> --- a/drivers/char/tpm/tpm2-cmd.c
> +++ b/drivers/char/tpm/tpm2-cmd.c
> @@ -165,14 +165,18 @@ struct tpm2_pcr_read_out {
> int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
> struct tpm_digest *digest, u16 *digest_size_ptr)
> {
> + struct tpm_buf *buf __free(kfree) = NULL;
> int i;
> int rc;
> - struct tpm_buf buf;
> struct tpm2_pcr_read_out *out;
> u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0};
> u16 digest_size;
> u16 expected_digest_size = 0;
>
> + buf = tpm_buf_alloc();
> + if (!buf)
> + return -ENOMEM;
> +
> if (pcr_idx >= TPM2_PLATFORM_PCR)
> return -EINVAL;
>
> @@ -187,23 +191,21 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
> expected_digest_size = chip->allocated_banks[i].digest_size;
> }
>
> - rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
> - if (rc)
> - return rc;
> + tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
>
> pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
>
> - tpm_buf_append_u32(&buf, 1);
> - tpm_buf_append_u16(&buf, digest->alg_id);
> - tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN);
> - tpm_buf_append(&buf, (const unsigned char *)pcr_select,
> + tpm_buf_append_u32(buf, 1);
> + tpm_buf_append_u16(buf, digest->alg_id);
> + tpm_buf_append_u8(buf, TPM2_PCR_SELECT_MIN);
> + tpm_buf_append(buf, (const unsigned char *)pcr_select,
> sizeof(pcr_select));
>
> - rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to read a pcr value");
> + rc = tpm_transmit_cmd(chip, buf, 0, "attempting to read a pcr value");
> if (rc)
> goto out;
nit: -> return rc; ?
>
> - out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
> + out = (struct tpm2_pcr_read_out *)&buf->data[TPM_HEADER_SIZE];
> digest_size = be16_to_cpu(out->digest_size);
> if (digest_size > sizeof(digest->digest) ||
> (!digest_size_ptr && digest_size != expected_digest_size)) {
> @@ -216,7 +218,6 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
>
> memcpy(digest->digest, out->digest, digest_size);
> out:
probably can remove this label
> - tpm_buf_destroy(&buf);
> return rc;
> }
>
> @@ -574,8 +569,8 @@ struct tpm2_pcr_selection {
>
> ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
> {
> + struct tpm_buf *buf __free(kfree) = NULL;
> struct tpm2_pcr_selection pcr_selection;
> - struct tpm_buf buf;
> void *marker;
> void *end;
> void *pcr_select_offset;
> @@ -587,41 +582,39 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
> int rc;
> int i = 0;
>
> - rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
> - if (rc)
> - return rc;
> + buf = tpm_buf_alloc();
> + if (!buf)
> + return -ENOMEM;
>
> - tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
> - tpm_buf_append_u32(&buf, 0);
> - tpm_buf_append_u32(&buf, 1);
> + tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
> + tpm_buf_append_u32(buf, TPM2_CAP_PCRS);
> + tpm_buf_append_u32(buf, 0);
> + tpm_buf_append_u32(buf, 1);
>
> - rc = tpm_transmit_cmd(chip, &buf, 9, "get tpm pcr allocation");
> + rc = tpm_transmit_cmd(chip, buf, 9, "get tpm pcr allocation");
> if (rc)
> - goto out;
> + return rc;
>
> nr_possible_banks = be32_to_cpup(
> - (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
> + (__be32 *)&buf->data[TPM_HEADER_SIZE + 5]);
>
> chip->allocated_banks = kcalloc(nr_possible_banks,
> sizeof(*chip->allocated_banks),
> GFP_KERNEL);
> - if (!chip->allocated_banks) {
> - rc = -ENOMEM;
> - goto out;
> - }
> + if (!chip->allocated_banks)
> + return -ENOMEM;
>
> - marker = &buf.data[TPM_HEADER_SIZE + 9];
> + marker = &buf->data[TPM_HEADER_SIZE + 9];
>
> - rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
> - end = &buf.data[rsp_len];
> + rsp_len = be32_to_cpup((__be32 *)&buf->data[2]);
> + end = &buf->data[rsp_len];
>
> + return rc;
this doesn't look right...
> for (i = 0; i < nr_possible_banks; i++) {
> pcr_select_offset = marker +
> offsetof(struct tpm2_pcr_selection, size_of_select);
> - if (pcr_select_offset >= end) {
> - rc = -EFAULT;
> - break;
> - }
> + if (pcr_select_offset >= end)
> + return -EFAULT;
>
> memcpy(&pcr_selection, marker, sizeof(pcr_selection));
> hash_alg = be16_to_cpu(pcr_selection.hash_alg);
> @@ -633,7 +626,7 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
> diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
> index 024be262702f..54bcd8d0621e 100644
> --- a/security/keys/trusted-keys/trusted_tpm2.c
> +++ b/security/keys/trusted-keys/trusted_tpm2.c
> @@ -241,14 +241,23 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
> struct trusted_key_payload *payload,
> struct trusted_key_options *options)
> {
> + struct tpm_buf *buf __free(kfree) = NULL;
> + struct tpm_buf *sized __free(kfree) = NULL;
Revert order of the above two lines.
> off_t offset = TPM_HEADER_SIZE;
> - struct tpm_buf buf, sized;
> int blob_len = 0;
> u32 hash;
> u32 flags;
> int i;
> int rc;
>
> + buf = tpm_buf_alloc();
> + if (!buf)
> + return -ENOMEM;
> +
> + sized = tpm_buf_alloc();
> + if (!sized)
> + return -ENOMEM;
> +
> for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {> if
(options->hash == tpm2_hash_map[i].crypto_id) {
> hash = tpm2_hash_map[i].tpm_id;
> @@ -270,89 +279,76 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
> if (rc)
> goto out_put;
>
> - rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
> - if (rc) {
> - tpm2_end_auth_session(chip);
> - goto out_put;
> - }
> -
> - rc = tpm_buf_init_sized(&sized);
> - if (rc) {
> - tpm_buf_destroy(&buf);
> - tpm2_end_auth_session(chip);
> - goto out_put;
> - }
> -
> - tpm_buf_append_name(chip, &buf, options->keyhandle, NULL);
> - tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_DECRYPT,
> + tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
> + tpm_buf_reset_sized(sized);
> + tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
> + tpm_buf_append_hmac_session(chip, buf, TPM2_SA_DECRYPT,
> options->keyauth, TPM_DIGEST_SIZE);
>
> /* sensitive */
> - tpm_buf_append_u16(&sized, options->blobauth_len);
> + tpm_buf_append_u16(sized, options->blobauth_len);
>
> if (options->blobauth_len)
> - tpm_buf_append(&sized, options->blobauth, options->blobauth_len);
> + tpm_buf_append(sized, options->blobauth, options->blobauth_len);
>
> - tpm_buf_append_u16(&sized, payload->key_len);
> - tpm_buf_append(&sized, payload->key, payload->key_len);
> - tpm_buf_append(&buf, sized.data, sized.length);
> + tpm_buf_append_u16(sized, payload->key_len);
> + tpm_buf_append(sized, payload->key, payload->key_len);
> + tpm_buf_append(buf, sized->data, sized->length);
>
> /* public */
> - tpm_buf_reset_sized(&sized);
> - tpm_buf_append_u16(&sized, TPM_ALG_KEYEDHASH);
> - tpm_buf_append_u16(&sized, hash);
> + tpm_buf_reset_sized(sized);
> + tpm_buf_append_u16(sized, TPM_ALG_KEYEDHASH);
> + tpm_buf_append_u16(sized, hash);
>
> /* key properties */
> flags = 0;
> flags |= options->policydigest_len ? 0 : TPM2_OA_USER_WITH_AUTH;
> flags |= payload->migratable ? 0 : (TPM2_OA_FIXED_TPM | TPM2_OA_FIXED_PARENT);
> - tpm_buf_append_u32(&sized, flags);
> + tpm_buf_append_u32(sized, flags);
>
> /* policy */
> - tpm_buf_append_u16(&sized, options->policydigest_len);
> + tpm_buf_append_u16(sized, options->policydigest_len);
> if (options->policydigest_len)
> - tpm_buf_append(&sized, options->policydigest, options->policydigest_len);
> + tpm_buf_append(sized, options->policydigest, options->policydigest_len);
>
> /* public parameters */
> - tpm_buf_append_u16(&sized, TPM_ALG_NULL);
> - tpm_buf_append_u16(&sized, 0);
> + tpm_buf_append_u16(sized, TPM_ALG_NULL);
> + tpm_buf_append_u16(sized, 0);
>
> - tpm_buf_append(&buf, sized.data, sized.length);
> + tpm_buf_append(buf, sized->data, sized->length);
>
> /* outside info */
> - tpm_buf_append_u16(&buf, 0);
> + tpm_buf_append_u16(buf, 0);
>
> /* creation PCR */
> - tpm_buf_append_u32(&buf, 0);
> + tpm_buf_append_u32(buf, 0);
>
> - if (buf.flags & TPM_BUF_OVERFLOW) {
> + if (buf->flags & TPM_BUF_OVERFLOW) {
> rc = -E2BIG;
> tpm2_end_auth_session(chip);
> goto out;
> }
>
> - tpm_buf_fill_hmac_session(chip, &buf);
> - rc = tpm_transmit_cmd(chip, &buf, 4, "sealing data");
> - rc = tpm_buf_check_hmac_response(chip, &buf, rc);
> + tpm_buf_fill_hmac_session(chip, buf);
> + rc = tpm_transmit_cmd(chip, buf, 4, "sealing data");
> + rc = tpm_buf_check_hmac_response(chip, buf, rc);
> if (rc)
> goto out;
>
> - blob_len = tpm_buf_read_u32(&buf, &offset);
> - if (blob_len > MAX_BLOB_SIZE || buf.flags & TPM_BUF_BOUNDARY_ERROR) {
> + blob_len = tpm_buf_read_u32(buf, &offset);
> + if (blob_len > MAX_BLOB_SIZE || buf->flags & TPM_BUF_BOUNDARY_ERROR) {
> rc = -E2BIG;
> goto out;
> }
> - if (buf.length - offset < blob_len) {
> + if (buf->length - offset < blob_len) {
> rc = -EFAULT;
> goto out;
> }
>
> - blob_len = tpm2_key_encode(payload, options, &buf.data[offset], blob_len);
> + blob_len = tpm2_key_encode(payload, options, &buf->data[offset],
> + blob_len);
>
> out:
> - tpm_buf_destroy(&sized);
> - tpm_buf_destroy(&buf);
> -
> if (rc > 0) {
> if (tpm2_rc_value(rc) == TPM2_RC_HASH)
> rc = -EINVAL;
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v4] tpm: Managed allocations for tpm_buf instances
2025-07-01 14:51 [PATCH v4] tpm: Managed allocations for tpm_buf instances Jarkko Sakkinen
2025-07-01 21:42 ` Stefan Berger
@ 2025-07-02 2:51 ` James Bottomley
2025-07-02 22:39 ` Jarkko Sakkinen
2025-07-02 12:57 ` Jason Gunthorpe
2 siblings, 1 reply; 7+ messages in thread
From: James Bottomley @ 2025-07-02 2:51 UTC (permalink / raw)
To: Jarkko Sakkinen, linux-kernel
Cc: keyrings, Stefan Berger, Jarkko Sakkinen, Peter Huewe,
Jason Gunthorpe, Mimi Zohar, David Howells, Paul Moore,
James Morris, Serge E. Hallyn, open list:TPM DEVICE DRIVER,
open list:SECURITY SUBSYSTEM
On Tue, 2025-07-01 at 17:51 +0300, Jarkko Sakkinen wrote:
> Repeal and replace tpm_buf_init() and tpm_buf_init_sized() with
> tpm_buf_alloc(), which returns a buffer of memory with the struct
> tpm_buf header at the beginning of the returned buffer. This leaves
> 4090 bytes of free space for the payload.
Shouldn't this be accounted for in tpm_buf_append()? right now it will
let us run off the end of the allocation by six bytes before it signals
overflow because it's checking final length against PAGE_SIZE not
PAGE_SIZE - sizeof(struct tpm_buf). I realise this should be an
impossible condition in production, but it's useful for debugging so we
should be accurate about it to avoid hard to detect bugs.
Regards,
James
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v4] tpm: Managed allocations for tpm_buf instances
2025-07-01 14:51 [PATCH v4] tpm: Managed allocations for tpm_buf instances Jarkko Sakkinen
2025-07-01 21:42 ` Stefan Berger
2025-07-02 2:51 ` James Bottomley
@ 2025-07-02 12:57 ` Jason Gunthorpe
2025-07-02 22:42 ` Jarkko Sakkinen
2 siblings, 1 reply; 7+ messages in thread
From: Jason Gunthorpe @ 2025-07-02 12:57 UTC (permalink / raw)
To: Jarkko Sakkinen
Cc: linux-kernel, keyrings, Stefan Berger, Jarkko Sakkinen,
Peter Huewe, James Bottomley, Mimi Zohar, David Howells,
Paul Moore, James Morris, Serge E. Hallyn,
open list:TPM DEVICE DRIVER, open list:SECURITY SUBSYSTEM
On Tue, Jul 01, 2025 at 05:51:35PM +0300, Jarkko Sakkinen wrote:
> @@ -32,28 +32,30 @@ struct tpm_readpubek_out {
> static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
> char *buf)
> {
> - struct tpm_buf tpm_buf;
> + struct tpm_buf *tpm_buf __free(kfree) = NULL;
> struct tpm_readpubek_out *out;
> int i;
> char *str = buf;
> struct tpm_chip *chip = to_tpm_chip(dev);
> char anti_replay[20];
>
> + tpm_buf = tpm_buf_alloc();
> + if (!tpm_buf)
> + return -ENOMEM;
apprently this isn't the style guide, you are supposed to write:
char anti_replay[20];
struct tpm_buf *tpm_buf __free(kfree) = tpm_buf_alloc();
if (!tpm_buf)
return -ENOMEM;
Jason
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v4] tpm: Managed allocations for tpm_buf instances
2025-07-01 21:42 ` Stefan Berger
@ 2025-07-02 22:38 ` Jarkko Sakkinen
0 siblings, 0 replies; 7+ messages in thread
From: Jarkko Sakkinen @ 2025-07-02 22:38 UTC (permalink / raw)
To: Stefan Berger
Cc: linux-kernel, keyrings, Jarkko Sakkinen, Peter Huewe,
Jason Gunthorpe, James Bottomley, Mimi Zohar, David Howells,
Paul Moore, James Morris, Serge E. Hallyn,
open list:TPM DEVICE DRIVER, open list:SECURITY SUBSYSTEM
On Tue, Jul 01, 2025 at 05:42:47PM -0400, Stefan Berger wrote:
>
>
> On 7/1/25 10:51 AM, Jarkko Sakkinen wrote:
> > From: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
> >
> > Repeal and replace tpm_buf_init() and tpm_buf_init_sized() with
> > tpm_buf_alloc(), which returns a buffer of memory with the struct tpm_buf
> > header at the beginning of the returned buffer. This leaves 4090 bytes of
> > free space for the payload.
> >
> > Given that kfree() is now the destructor for struct tpm_buf instances,
> > tpm_buf_destroy() becomes obsolete, and can be safely wiped of too.
>
> s/of/off/ or s/wiped of/remove,/
>
> >
> > The actual gist is that now a tpm_buf can be now declared using
>
> s/that now a/that a/
>
> > __free(kfree) declared in linux/slab.h:
> >
> > struct tpm_buf *buf __free(kfree) = NULL;
> >
> > /* ... */
> >
> > buf = tpm_buf_alloc();
> >
> > Doing this has two-folded benefits:
> >
> > 1. Yet to be discoverd memory leaks in the pre-existing code base.
>
> -> discovered
>
>
> A couple of nits below and one stray 'return rc;' that should not be
> there...
>
> > 2. Memory leaks concerning new features and other contributions.
> >
> > In addition, the barrier to contribute is lowered given that managing
> > memory is a factor easier.
> >
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@opinsys.com>
> > diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> > index 524d802ede26..86b961f4027b 100644
> > --- a/drivers/char/tpm/tpm2-cmd.c
> > +++ b/drivers/char/tpm/tpm2-cmd.c
> > @@ -165,14 +165,18 @@ struct tpm2_pcr_read_out {
> > int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
> > struct tpm_digest *digest, u16 *digest_size_ptr)
> > {
> > + struct tpm_buf *buf __free(kfree) = NULL;
> > int i;
> > int rc;
> > - struct tpm_buf buf;
> > struct tpm2_pcr_read_out *out;
> > u8 pcr_select[TPM2_PCR_SELECT_MIN] = {0};
> > u16 digest_size;
> > u16 expected_digest_size = 0;
> > + buf = tpm_buf_alloc();
> > + if (!buf)
> > + return -ENOMEM;
> > +
> > if (pcr_idx >= TPM2_PLATFORM_PCR)
> > return -EINVAL;
> > @@ -187,23 +191,21 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
> > expected_digest_size = chip->allocated_banks[i].digest_size;
> > }
> > - rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
> > - if (rc)
> > - return rc;
> > + tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_PCR_READ);
> > pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
> > - tpm_buf_append_u32(&buf, 1);
> > - tpm_buf_append_u16(&buf, digest->alg_id);
> > - tpm_buf_append_u8(&buf, TPM2_PCR_SELECT_MIN);
> > - tpm_buf_append(&buf, (const unsigned char *)pcr_select,
> > + tpm_buf_append_u32(buf, 1);
> > + tpm_buf_append_u16(buf, digest->alg_id);
> > + tpm_buf_append_u8(buf, TPM2_PCR_SELECT_MIN);
> > + tpm_buf_append(buf, (const unsigned char *)pcr_select,
> > sizeof(pcr_select));
> > - rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to read a pcr value");
> > + rc = tpm_transmit_cmd(chip, buf, 0, "attempting to read a pcr value");
> > if (rc)
> > goto out;
>
> nit: -> return rc; ?
>
> > - out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE];
> > + out = (struct tpm2_pcr_read_out *)&buf->data[TPM_HEADER_SIZE];
> > digest_size = be16_to_cpu(out->digest_size);
> > if (digest_size > sizeof(digest->digest) ||
> > (!digest_size_ptr && digest_size != expected_digest_size)) {
> > @@ -216,7 +218,6 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
> > memcpy(digest->digest, out->digest, digest_size);
> > out:
>
> probably can remove this label
yup, i agree
>
> > - tpm_buf_destroy(&buf);
> > return rc;
> > }
> > @@ -574,8 +569,8 @@ struct tpm2_pcr_selection {
> > ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
> > {
> > + struct tpm_buf *buf __free(kfree) = NULL;
> > struct tpm2_pcr_selection pcr_selection;
> > - struct tpm_buf buf;
> > void *marker;
> > void *end;
> > void *pcr_select_offset;
> > @@ -587,41 +582,39 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
> > int rc;
> > int i = 0;
> > - rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
> > - if (rc)
> > - return rc;
> > + buf = tpm_buf_alloc();
> > + if (!buf)
> > + return -ENOMEM;
> > - tpm_buf_append_u32(&buf, TPM2_CAP_PCRS);
> > - tpm_buf_append_u32(&buf, 0);
> > - tpm_buf_append_u32(&buf, 1);
> > + tpm_buf_reset(buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY);
> > + tpm_buf_append_u32(buf, TPM2_CAP_PCRS);
> > + tpm_buf_append_u32(buf, 0);
> > + tpm_buf_append_u32(buf, 1);
> > - rc = tpm_transmit_cmd(chip, &buf, 9, "get tpm pcr allocation");
> > + rc = tpm_transmit_cmd(chip, buf, 9, "get tpm pcr allocation");
> > if (rc)
> > - goto out;
> > + return rc;
> > nr_possible_banks = be32_to_cpup(
> > - (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]);
> > + (__be32 *)&buf->data[TPM_HEADER_SIZE + 5]);
> > chip->allocated_banks = kcalloc(nr_possible_banks,
> > sizeof(*chip->allocated_banks),
> > GFP_KERNEL);
> > - if (!chip->allocated_banks) {
> > - rc = -ENOMEM;
> > - goto out;
> > - }
> > + if (!chip->allocated_banks)
> > + return -ENOMEM;
> > - marker = &buf.data[TPM_HEADER_SIZE + 9];
> > + marker = &buf->data[TPM_HEADER_SIZE + 9];
> > - rsp_len = be32_to_cpup((__be32 *)&buf.data[2]);
> > - end = &buf.data[rsp_len];
> > + rsp_len = be32_to_cpup((__be32 *)&buf->data[2]);
> > + end = &buf->data[rsp_len];
> > + return rc;
>
>
> this doesn't look right...
thanks for catching this!
>
>
> > for (i = 0; i < nr_possible_banks; i++) {
> > pcr_select_offset = marker +
> > offsetof(struct tpm2_pcr_selection, size_of_select);
> > - if (pcr_select_offset >= end) {
> > - rc = -EFAULT;
> > - break;
> > - }
> > + if (pcr_select_offset >= end)
> > + return -EFAULT;
> > memcpy(&pcr_selection, marker, sizeof(pcr_selection));
> > hash_alg = be16_to_cpu(pcr_selection.hash_alg);
> > @@ -633,7 +626,7 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
> > diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
> > index 024be262702f..54bcd8d0621e 100644
> > --- a/security/keys/trusted-keys/trusted_tpm2.c
> > +++ b/security/keys/trusted-keys/trusted_tpm2.c
> > @@ -241,14 +241,23 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
> > struct trusted_key_payload *payload,
> > struct trusted_key_options *options)
> > {
> > + struct tpm_buf *buf __free(kfree) = NULL;
> > + struct tpm_buf *sized __free(kfree) = NULL;
>
> Revert order of the above two lines.
>
> > off_t offset = TPM_HEADER_SIZE;
> > - struct tpm_buf buf, sized;
> > int blob_len = 0;
> > u32 hash;
> > u32 flags;
> > int i;
> > int rc;
> > + buf = tpm_buf_alloc();
> > + if (!buf)
> > + return -ENOMEM;
> > +
> > + sized = tpm_buf_alloc();
> > + if (!sized)
> > + return -ENOMEM;
> > +
> > for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {> if
> (options->hash == tpm2_hash_map[i].crypto_id) {
> > hash = tpm2_hash_map[i].tpm_id;
> > @@ -270,89 +279,76 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
> > if (rc)
> > goto out_put;
> > - rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
> > - if (rc) {
> > - tpm2_end_auth_session(chip);
> > - goto out_put;
> > - }
> > -
> > - rc = tpm_buf_init_sized(&sized);
> > - if (rc) {
> > - tpm_buf_destroy(&buf);
> > - tpm2_end_auth_session(chip);
> > - goto out_put;
> > - }
> > -
> > - tpm_buf_append_name(chip, &buf, options->keyhandle, NULL);
> > - tpm_buf_append_hmac_session(chip, &buf, TPM2_SA_DECRYPT,
> > + tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
> > + tpm_buf_reset_sized(sized);
> > + tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
> > + tpm_buf_append_hmac_session(chip, buf, TPM2_SA_DECRYPT,
> > options->keyauth, TPM_DIGEST_SIZE);
> > /* sensitive */
> > - tpm_buf_append_u16(&sized, options->blobauth_len);
> > + tpm_buf_append_u16(sized, options->blobauth_len);
> > if (options->blobauth_len)
> > - tpm_buf_append(&sized, options->blobauth, options->blobauth_len);
> > + tpm_buf_append(sized, options->blobauth, options->blobauth_len);
> > - tpm_buf_append_u16(&sized, payload->key_len);
> > - tpm_buf_append(&sized, payload->key, payload->key_len);
> > - tpm_buf_append(&buf, sized.data, sized.length);
> > + tpm_buf_append_u16(sized, payload->key_len);
> > + tpm_buf_append(sized, payload->key, payload->key_len);
> > + tpm_buf_append(buf, sized->data, sized->length);
> > /* public */
> > - tpm_buf_reset_sized(&sized);
> > - tpm_buf_append_u16(&sized, TPM_ALG_KEYEDHASH);
> > - tpm_buf_append_u16(&sized, hash);
> > + tpm_buf_reset_sized(sized);
> > + tpm_buf_append_u16(sized, TPM_ALG_KEYEDHASH);
> > + tpm_buf_append_u16(sized, hash);
> > /* key properties */
> > flags = 0;
> > flags |= options->policydigest_len ? 0 : TPM2_OA_USER_WITH_AUTH;
> > flags |= payload->migratable ? 0 : (TPM2_OA_FIXED_TPM | TPM2_OA_FIXED_PARENT);
> > - tpm_buf_append_u32(&sized, flags);
> > + tpm_buf_append_u32(sized, flags);
> > /* policy */
> > - tpm_buf_append_u16(&sized, options->policydigest_len);
> > + tpm_buf_append_u16(sized, options->policydigest_len);
> > if (options->policydigest_len)
> > - tpm_buf_append(&sized, options->policydigest, options->policydigest_len);
> > + tpm_buf_append(sized, options->policydigest, options->policydigest_len);
> > /* public parameters */
> > - tpm_buf_append_u16(&sized, TPM_ALG_NULL);
> > - tpm_buf_append_u16(&sized, 0);
> > + tpm_buf_append_u16(sized, TPM_ALG_NULL);
> > + tpm_buf_append_u16(sized, 0);
> > - tpm_buf_append(&buf, sized.data, sized.length);
> > + tpm_buf_append(buf, sized->data, sized->length);
> > /* outside info */
> > - tpm_buf_append_u16(&buf, 0);
> > + tpm_buf_append_u16(buf, 0);
> > /* creation PCR */
> > - tpm_buf_append_u32(&buf, 0);
> > + tpm_buf_append_u32(buf, 0);
> > - if (buf.flags & TPM_BUF_OVERFLOW) {
> > + if (buf->flags & TPM_BUF_OVERFLOW) {
> > rc = -E2BIG;
> > tpm2_end_auth_session(chip);
> > goto out;
> > }
> > - tpm_buf_fill_hmac_session(chip, &buf);
> > - rc = tpm_transmit_cmd(chip, &buf, 4, "sealing data");
> > - rc = tpm_buf_check_hmac_response(chip, &buf, rc);
> > + tpm_buf_fill_hmac_session(chip, buf);
> > + rc = tpm_transmit_cmd(chip, buf, 4, "sealing data");
> > + rc = tpm_buf_check_hmac_response(chip, buf, rc);
> > if (rc)
> > goto out;
> > - blob_len = tpm_buf_read_u32(&buf, &offset);
> > - if (blob_len > MAX_BLOB_SIZE || buf.flags & TPM_BUF_BOUNDARY_ERROR) {
> > + blob_len = tpm_buf_read_u32(buf, &offset);
> > + if (blob_len > MAX_BLOB_SIZE || buf->flags & TPM_BUF_BOUNDARY_ERROR) {
> > rc = -E2BIG;
> > goto out;
> > }
> > - if (buf.length - offset < blob_len) {
> > + if (buf->length - offset < blob_len) {
> > rc = -EFAULT;
> > goto out;
> > }
> > - blob_len = tpm2_key_encode(payload, options, &buf.data[offset], blob_len);
> > + blob_len = tpm2_key_encode(payload, options, &buf->data[offset],
> > + blob_len);
> > out:
> > - tpm_buf_destroy(&sized);
> > - tpm_buf_destroy(&buf);
> > -
> > if (rc > 0) {
> > if (tpm2_rc_value(rc) == TPM2_RC_HASH)
> > rc = -EINVAL;
Thanks for the remarks.
BR, Jarkko
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v4] tpm: Managed allocations for tpm_buf instances
2025-07-02 2:51 ` James Bottomley
@ 2025-07-02 22:39 ` Jarkko Sakkinen
0 siblings, 0 replies; 7+ messages in thread
From: Jarkko Sakkinen @ 2025-07-02 22:39 UTC (permalink / raw)
To: James Bottomley
Cc: linux-kernel, keyrings, Stefan Berger, Jarkko Sakkinen,
Peter Huewe, Jason Gunthorpe, Mimi Zohar, David Howells,
Paul Moore, James Morris, Serge E. Hallyn,
open list:TPM DEVICE DRIVER, open list:SECURITY SUBSYSTEM
On Tue, Jul 01, 2025 at 10:51:55PM -0400, James Bottomley wrote:
> On Tue, 2025-07-01 at 17:51 +0300, Jarkko Sakkinen wrote:
> > Repeal and replace tpm_buf_init() and tpm_buf_init_sized() with
> > tpm_buf_alloc(), which returns a buffer of memory with the struct
> > tpm_buf header at the beginning of the returned buffer. This leaves
> > 4090 bytes of free space for the payload.
>
> Shouldn't this be accounted for in tpm_buf_append()? right now it will
> let us run off the end of the allocation by six bytes before it signals
> overflow because it's checking final length against PAGE_SIZE not
> PAGE_SIZE - sizeof(struct tpm_buf). I realise this should be an
> impossible condition in production, but it's useful for debugging so we
> should be accurate about it to avoid hard to detect bugs.
Fully agree. Thanks for pointing this out!
>
> Regards,
>
> James
>
BR, Jarkko
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH v4] tpm: Managed allocations for tpm_buf instances
2025-07-02 12:57 ` Jason Gunthorpe
@ 2025-07-02 22:42 ` Jarkko Sakkinen
0 siblings, 0 replies; 7+ messages in thread
From: Jarkko Sakkinen @ 2025-07-02 22:42 UTC (permalink / raw)
To: Jason Gunthorpe
Cc: linux-kernel, keyrings, Stefan Berger, Jarkko Sakkinen,
Peter Huewe, James Bottomley, Mimi Zohar, David Howells,
Paul Moore, James Morris, Serge E. Hallyn,
open list:TPM DEVICE DRIVER, open list:SECURITY SUBSYSTEM
On Wed, Jul 02, 2025 at 09:57:25AM -0300, Jason Gunthorpe wrote:
> On Tue, Jul 01, 2025 at 05:51:35PM +0300, Jarkko Sakkinen wrote:
> > @@ -32,28 +32,30 @@ struct tpm_readpubek_out {
> > static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
> > char *buf)
> > {
> > - struct tpm_buf tpm_buf;
> > + struct tpm_buf *tpm_buf __free(kfree) = NULL;
> > struct tpm_readpubek_out *out;
> > int i;
> > char *str = buf;
> > struct tpm_chip *chip = to_tpm_chip(dev);
> > char anti_replay[20];
> >
> > + tpm_buf = tpm_buf_alloc();
> > + if (!tpm_buf)
> > + return -ENOMEM;
>
> apprently this isn't the style guide, you are supposed to write:
>
> char anti_replay[20];
>
> struct tpm_buf *tpm_buf __free(kfree) = tpm_buf_alloc();
> if (!tpm_buf)
> return -ENOMEM;
Sounds fair to me. I'll shift to this direction in the next revision.
>
> Jason
BR, Jarkko
BR, Jarkko
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2025-07-02 22:42 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-07-01 14:51 [PATCH v4] tpm: Managed allocations for tpm_buf instances Jarkko Sakkinen
2025-07-01 21:42 ` Stefan Berger
2025-07-02 22:38 ` Jarkko Sakkinen
2025-07-02 2:51 ` James Bottomley
2025-07-02 22:39 ` Jarkko Sakkinen
2025-07-02 12:57 ` Jason Gunthorpe
2025-07-02 22:42 ` Jarkko Sakkinen
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