On 6/17/20 12:04 PM, Stefan Berger wrote:
On 6/16/20 6:30 PM, Stefan Berger wrote:
I am upgrading libtpms's TPM 2 to support RSA 3072 keys (increase
context size to 2680 bytes) and wanted to test an upgrade from
previous version (0.7.2) which only supports RSA 2048 keys to this
newer version (git master). I tried to run this with clevis setting
up automatic decryption via TPM 2, but it doesn't work and it seems
the issue is due to a stall of /dev/tpmr0 that doesn't respond anymore.
[...]
It's stuck polling on /dev/tpmrm0.
Any ideas?
It has something to do with the offset parameter and the PAGE_SIZE as
a limit.
[ 842.288597] *offset=0
[ 842.295345] *offset=2692
[ 842.301011] body_size=2692, *offset=2692, buf_size=4096
[ 842.301584] tpm tpm0: tpm2_save_context: out of backing storage
[ 842.305463] tpm tpm0: tpm2_commit_space: error -12
[ 850.793691] tpm tpm0: A TPM error (459) occurred flushing context
This here fixes it. Any suggestion for a proper fix?
Does it concatenate contexts into this PAGE_SIZE'd buffer?
This may be a better workable patch that needs to apply to many previous
kernel versions:
drivers/char/tpm/tpm-chip.c | 2 +-
drivers/char/tpm/tpm.h | 2 ++
drivers/char/tpm/tpm2-space.c | 12 ++++++++----
3 files changed, 11 insertions(+), 5 deletions(-)
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index 8c77e88012e9..d32a173117b8 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -386,7 +386,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev,
chip->cdev.owner = THIS_MODULE;
chip->cdevs.owner = THIS_MODULE;
- chip->work_space.context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+ chip->work_space.context_buf = kzalloc(TPM_SPACE_SIZE, GFP_KERNEL);
if (!chip->work_space.context_buf) {
rc = -ENOMEM;
goto out;
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 0fbcede241ea..5f34187da858 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -36,6 +36,8 @@
#define TPM_NUM_DEVICES 65536
#define TPM_RETRY 50
+#define TPM_SPACE_SIZE (3 * 4096)
+
enum tpm_timeout {
TPM_TIMEOUT = 5, /* msecs */
TPM_TIMEOUT_RETRY = 100, /* msecs */
diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
index 982d341d8837..493900008fa2 100644
--- a/drivers/char/tpm/tpm2-space.c
+++ b/drivers/char/tpm/tpm2-space.c
@@ -40,7 +40,7 @@ static void tpm2_flush_sessions(struct tpm_chip *chip,
struct tpm_space *space)
int tpm2_init_space(struct tpm_space *space)
{
- space->context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+ space->context_buf = kzalloc(TPM_SPACE_SIZE, GFP_KERNEL);
if (!space->context_buf)
return -ENOMEM;
@@ -123,6 +123,7 @@ static int tpm2_save_context(struct tpm_chip *chip,
u32 handle, u8 *buf,
unsigned int body_size;
int rc;
+printk(KERN_INFO "*offset=%u\n", *offset);
rc = tpm_buf_init(&tbuf, TPM2_ST_NO_SESSIONS, TPM2_CC_CONTEXT_SAVE);
if (rc)
return rc;
@@ -147,6 +148,7 @@ static int tpm2_save_context(struct tpm_chip *chip,
u32 handle, u8 *buf,
body_size = tpm_buf_length(&tbuf) - TPM_HEADER_SIZE;
if ((*offset + body_size) > buf_size) {
+printk(KERN_INFO "body_size=%u, *offset=%u, buf_size=%u\n", body_size,
*offset, buf_size);
dev_warn(&chip->dev, "%s: out of backing storage\n", __func__);
tpm_buf_destroy(&tbuf);
return -ENOMEM;
@@ -311,7 +313,7 @@ int tpm2_prepare_space(struct tpm_chip *chip, struct
tpm_space *space, u8 *cmd,
sizeof(space->context_tbl));
memcpy(&chip->work_space.session_tbl, &space->session_tbl,
sizeof(space->session_tbl));
- memcpy(chip->work_space.context_buf, space->context_buf, PAGE_SIZE);
+ memcpy(chip->work_space.context_buf, space->context_buf,
TPM_SPACE_SIZE);
memcpy(chip->work_space.session_buf, space->session_buf, PAGE_SIZE);
rc = tpm2_load_space(chip);
@@ -487,12 +489,13 @@ static int tpm2_save_space(struct tpm_chip *chip)
int i;
int rc;
+ printk(KERN_INFO "ARRAY_SIZE(space->context_tbl) = %lu\n",
ARRAY_SIZE(space->context_tbl));
for (i = 0, offset = 0; i < ARRAY_SIZE(space->context_tbl); i++) {
if (!(space->context_tbl[i] && ~space->context_tbl[i]))
continue;
rc = tpm2_save_context(chip, space->context_tbl[i],
- space->context_buf, PAGE_SIZE,
+ space->context_buf, TPM_SPACE_SIZE,
&offset);
if (rc == -ENOENT) {
space->context_tbl[i] = 0;
@@ -530,6 +533,7 @@ int tpm2_commit_space(struct tpm_chip *chip, struct
tpm_space *space,
struct tpm_header *header = buf;
int rc;
+printk(KERN_INFO "%s:%d\n", __func__, __LINE__);
if (!space)
return 0;
@@ -557,7 +561,7 @@ int tpm2_commit_space(struct tpm_chip *chip, struct
tpm_space *space,
sizeof(space->context_tbl));
memcpy(&space->session_tbl, &chip->work_space.session_tbl,
sizeof(space->session_tbl));
- memcpy(space->context_buf, chip->work_space.context_buf, PAGE_SIZE);
+ memcpy(space->context_buf, chip->work_space.context_buf,
TPM_SPACE_SIZE);
memcpy(space->session_buf, chip->work_space.session_buf, PAGE_SIZE);
return 0;
