| Message ID | 20181213102945.30946-2-roberto.sassu@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | tpm: retrieve digest size of unknown algorithms from TPM | expand |
On Thu, Dec 13, 2018 at 11:29:41AM +0100, Roberto Sassu wrote: > This patch renames active_banks (member of tpm_chip) to allocated_banks, > stores the number of allocated PCR banks in nr_allocated_banks (new member > of tpm_chip), and replaces the static array with a pointer to a dynamically > allocated array. > > tpm2_get_pcr_allocation() determines if a PCR bank is allocated by checking > the mask in the TPML_PCR_SELECTION structure returned by the TPM for > TPM2_Get_Capability(). If a bank is not allocated, the TPM returns that > bank in TPML_PCR_SELECTION, with all bits in the mask set to zero. In this > case, the bank is not included in chip->allocated_banks, to avoid that TPM > driver users unnecessarily calculate a digest for that bank. > > One PCR bank with algorithm set to SHA1 is always allocated for TPM 1.x. > > As a consequence of the introduction of nr_allocated_banks, > tpm_pcr_extend() does not check anymore if the algorithm stored in tpm_chip > is equal to zero. > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> > --- > drivers/char/tpm/tpm-chip.c | 1 + > drivers/char/tpm/tpm-interface.c | 18 +++++++++-------- > drivers/char/tpm/tpm.h | 3 ++- > drivers/char/tpm/tpm1-cmd.c | 10 ++++++++++ > drivers/char/tpm/tpm2-cmd.c | 34 ++++++++++++++++++++++---------- > 5 files changed, 47 insertions(+), 19 deletions(-) > > diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c > index 32db84683c40..ce851c62bb68 100644 > --- a/drivers/char/tpm/tpm-chip.c > +++ b/drivers/char/tpm/tpm-chip.c > @@ -160,6 +160,7 @@ static void tpm_dev_release(struct device *dev) > kfree(chip->log.bios_event_log); > kfree(chip->work_space.context_buf); > kfree(chip->work_space.session_buf); > + kfree(chip->allocated_banks); > kfree(chip); > } > > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c > index d9439f9abe78..7b80919228be 100644 > --- a/drivers/char/tpm/tpm-interface.c > +++ b/drivers/char/tpm/tpm-interface.c > @@ -488,8 +488,7 @@ EXPORT_SYMBOL_GPL(tpm_pcr_read); > int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) > { > int rc; > - struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; > - u32 count = 0; > + struct tpm2_digest *digest_list; > int i; > > chip = tpm_find_get_ops(chip); > @@ -497,16 +496,19 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) > return -ENODEV; > > if (chip->flags & TPM_CHIP_FLAG_TPM2) { > - memset(digest_list, 0, sizeof(digest_list)); > + digest_list = kcalloc(chip->nr_allocated_banks, > + sizeof(*digest_list), GFP_KERNEL); > + if (!digest_list) > + return -ENOMEM; You could preallocate digest list and place it to struct tpm_chip instead of doing it everytime tpm_pcr_extend() called. > > - for (i = 0; i < ARRAY_SIZE(chip->active_banks) && > - chip->active_banks[i] != TPM2_ALG_ERROR; i++) { > - digest_list[i].alg_id = chip->active_banks[i]; > + for (i = 0; i < chip->nr_allocated_banks; i++) { > + digest_list[i].alg_id = chip->allocated_banks[i]; > memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE); > - count++; > } > > - rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list); > + rc = tpm2_pcr_extend(chip, pcr_idx, chip->nr_allocated_banks, > + digest_list); > + kfree(digest_list); > tpm_put_ops(chip); > return rc; > } > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h > index f27d1f38a93d..6b94306ab7c5 100644 > --- a/drivers/char/tpm/tpm.h > +++ b/drivers/char/tpm/tpm.h > @@ -257,7 +257,8 @@ struct tpm_chip { > const struct attribute_group *groups[3]; > unsigned int groups_cnt; > > - u16 active_banks[7]; > + u32 nr_allocated_banks; > + u16 *allocated_banks; > #ifdef CONFIG_ACPI > acpi_handle acpi_dev_handle; > char ppi_version[TPM_PPI_VERSION_LEN + 1]; > diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c > index 6f306338953b..0874743ca96d 100644 > --- a/drivers/char/tpm/tpm1-cmd.c > +++ b/drivers/char/tpm/tpm1-cmd.c > @@ -709,6 +709,16 @@ int tpm1_auto_startup(struct tpm_chip *chip) > goto out; > } > > + chip->allocated_banks = kcalloc(1, sizeof(*chip->allocated_banks), > + GFP_KERNEL); > + if (!chip->allocated_banks) { > + rc = -ENOMEM; > + goto out; > + } > + > + chip->allocated_banks[0] = TPM2_ALG_SHA1; > + chip->nr_allocated_banks = 1; > + > return rc; > out: > if (rc > 0) > diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c > index a6bec13afa69..245669a7aba5 100644 > --- a/drivers/char/tpm/tpm2-cmd.c > +++ b/drivers/char/tpm/tpm2-cmd.c > @@ -234,7 +234,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, u32 count, > int i; > int j; > > - if (count > ARRAY_SIZE(chip->active_banks)) > + if (count > chip->nr_allocated_banks) > return -EINVAL; > > rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND); > @@ -825,11 +825,14 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) > void *marker; > void *end; > void *pcr_select_offset; > - unsigned int count; > u32 sizeof_pcr_selection; > + u32 nr_possible_banks; > + u32 nr_alloc_banks = 0; > + u16 hash_alg; > u32 rsp_len; > int rc; > int i = 0; > + int j; > > rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY); > if (rc) > @@ -844,11 +847,14 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) > if (rc) > goto out; > > - count = be32_to_cpup( > + nr_possible_banks = be32_to_cpup( > (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]); > > - if (count > ARRAY_SIZE(chip->active_banks)) { > - rc = -ENODEV; > + chip->allocated_banks = kcalloc(nr_possible_banks, > + sizeof(*chip->allocated_banks), > + GFP_KERNEL); > + if (!chip->allocated_banks) { > + rc = -ENOMEM; > goto out; > } > > @@ -857,7 +863,7 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) > rsp_len = be32_to_cpup((__be32 *)&buf.data[2]); > end = &buf.data[rsp_len]; > > - for (i = 0; i < count; i++) { > + 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) { > @@ -866,17 +872,25 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) > } > > memcpy(&pcr_selection, marker, sizeof(pcr_selection)); > - chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg); > + hash_alg = be16_to_cpu(pcr_selection.hash_alg); > + > + for (j = 0; j < pcr_selection.size_of_select; j++) > + if (pcr_selection.pcr_select[j]) > + break; > + > + if (j < pcr_selection.size_of_select) { > + chip->allocated_banks[nr_alloc_banks] = hash_alg; > + nr_alloc_banks++; > + } The same comment as before: you should use memchr_inv() here. > + > sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) + > sizeof(pcr_selection.size_of_select) + > pcr_selection.size_of_select; > marker = marker + sizeof_pcr_selection; > } > > + chip->nr_allocated_banks = nr_alloc_banks; > out: > - if (i < ARRAY_SIZE(chip->active_banks)) > - chip->active_banks[i] = TPM2_ALG_ERROR; > - > tpm_buf_destroy(&buf); > > return rc; > -- > 2.17.1 > /Jarkko
On 12/20/2018 3:55 PM, Jarkko Sakkinen wrote: > On Thu, Dec 13, 2018 at 11:29:41AM +0100, Roberto Sassu wrote: >> This patch renames active_banks (member of tpm_chip) to allocated_banks, >> stores the number of allocated PCR banks in nr_allocated_banks (new member >> of tpm_chip), and replaces the static array with a pointer to a dynamically >> allocated array. >> >> tpm2_get_pcr_allocation() determines if a PCR bank is allocated by checking >> the mask in the TPML_PCR_SELECTION structure returned by the TPM for >> TPM2_Get_Capability(). If a bank is not allocated, the TPM returns that >> bank in TPML_PCR_SELECTION, with all bits in the mask set to zero. In this >> case, the bank is not included in chip->allocated_banks, to avoid that TPM >> driver users unnecessarily calculate a digest for that bank. >> >> One PCR bank with algorithm set to SHA1 is always allocated for TPM 1.x. >> >> As a consequence of the introduction of nr_allocated_banks, >> tpm_pcr_extend() does not check anymore if the algorithm stored in tpm_chip >> is equal to zero. >> >> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> >> Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> >> --- >> drivers/char/tpm/tpm-chip.c | 1 + >> drivers/char/tpm/tpm-interface.c | 18 +++++++++-------- >> drivers/char/tpm/tpm.h | 3 ++- >> drivers/char/tpm/tpm1-cmd.c | 10 ++++++++++ >> drivers/char/tpm/tpm2-cmd.c | 34 ++++++++++++++++++++++---------- >> 5 files changed, 47 insertions(+), 19 deletions(-) >> >> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c >> index 32db84683c40..ce851c62bb68 100644 >> --- a/drivers/char/tpm/tpm-chip.c >> +++ b/drivers/char/tpm/tpm-chip.c >> @@ -160,6 +160,7 @@ static void tpm_dev_release(struct device *dev) >> kfree(chip->log.bios_event_log); >> kfree(chip->work_space.context_buf); >> kfree(chip->work_space.session_buf); >> + kfree(chip->allocated_banks); >> kfree(chip); >> } >> >> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c >> index d9439f9abe78..7b80919228be 100644 >> --- a/drivers/char/tpm/tpm-interface.c >> +++ b/drivers/char/tpm/tpm-interface.c >> @@ -488,8 +488,7 @@ EXPORT_SYMBOL_GPL(tpm_pcr_read); >> int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) >> { >> int rc; >> - struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; >> - u32 count = 0; >> + struct tpm2_digest *digest_list; >> int i; >> >> chip = tpm_find_get_ops(chip); >> @@ -497,16 +496,19 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) >> return -ENODEV; >> >> if (chip->flags & TPM_CHIP_FLAG_TPM2) { >> - memset(digest_list, 0, sizeof(digest_list)); >> + digest_list = kcalloc(chip->nr_allocated_banks, >> + sizeof(*digest_list), GFP_KERNEL); >> + if (!digest_list) >> + return -ENOMEM; > > You could preallocate digest list and place it to struct tpm_chip > instead of doing it everytime tpm_pcr_extend() called. This part will be removed with patch 5/5. >> - for (i = 0; i < ARRAY_SIZE(chip->active_banks) && >> - chip->active_banks[i] != TPM2_ALG_ERROR; i++) { >> - digest_list[i].alg_id = chip->active_banks[i]; >> + for (i = 0; i < chip->nr_allocated_banks; i++) { >> + digest_list[i].alg_id = chip->allocated_banks[i]; >> memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE); >> - count++; >> } >> >> - rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list); >> + rc = tpm2_pcr_extend(chip, pcr_idx, chip->nr_allocated_banks, >> + digest_list); >> + kfree(digest_list); >> tpm_put_ops(chip); >> return rc; >> } >> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h >> index f27d1f38a93d..6b94306ab7c5 100644 >> --- a/drivers/char/tpm/tpm.h >> +++ b/drivers/char/tpm/tpm.h >> @@ -257,7 +257,8 @@ struct tpm_chip { >> const struct attribute_group *groups[3]; >> unsigned int groups_cnt; >> >> - u16 active_banks[7]; >> + u32 nr_allocated_banks; >> + u16 *allocated_banks; >> #ifdef CONFIG_ACPI >> acpi_handle acpi_dev_handle; >> char ppi_version[TPM_PPI_VERSION_LEN + 1]; >> diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c >> index 6f306338953b..0874743ca96d 100644 >> --- a/drivers/char/tpm/tpm1-cmd.c >> +++ b/drivers/char/tpm/tpm1-cmd.c >> @@ -709,6 +709,16 @@ int tpm1_auto_startup(struct tpm_chip *chip) >> goto out; >> } >> >> + chip->allocated_banks = kcalloc(1, sizeof(*chip->allocated_banks), >> + GFP_KERNEL); >> + if (!chip->allocated_banks) { >> + rc = -ENOMEM; >> + goto out; >> + } >> + >> + chip->allocated_banks[0] = TPM2_ALG_SHA1; >> + chip->nr_allocated_banks = 1; >> + >> return rc; >> out: >> if (rc > 0) >> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c >> index a6bec13afa69..245669a7aba5 100644 >> --- a/drivers/char/tpm/tpm2-cmd.c >> +++ b/drivers/char/tpm/tpm2-cmd.c >> @@ -234,7 +234,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, u32 count, >> int i; >> int j; >> >> - if (count > ARRAY_SIZE(chip->active_banks)) >> + if (count > chip->nr_allocated_banks) >> return -EINVAL; >> >> rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND); >> @@ -825,11 +825,14 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) >> void *marker; >> void *end; >> void *pcr_select_offset; >> - unsigned int count; >> u32 sizeof_pcr_selection; >> + u32 nr_possible_banks; >> + u32 nr_alloc_banks = 0; >> + u16 hash_alg; >> u32 rsp_len; >> int rc; >> int i = 0; >> + int j; >> >> rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY); >> if (rc) >> @@ -844,11 +847,14 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) >> if (rc) >> goto out; >> >> - count = be32_to_cpup( >> + nr_possible_banks = be32_to_cpup( >> (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]); >> >> - if (count > ARRAY_SIZE(chip->active_banks)) { >> - rc = -ENODEV; >> + chip->allocated_banks = kcalloc(nr_possible_banks, >> + sizeof(*chip->allocated_banks), >> + GFP_KERNEL); >> + if (!chip->allocated_banks) { >> + rc = -ENOMEM; >> goto out; >> } >> >> @@ -857,7 +863,7 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) >> rsp_len = be32_to_cpup((__be32 *)&buf.data[2]); >> end = &buf.data[rsp_len]; >> >> - for (i = 0; i < count; i++) { >> + 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) { >> @@ -866,17 +872,25 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) >> } >> >> memcpy(&pcr_selection, marker, sizeof(pcr_selection)); >> - chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg); >> + hash_alg = be16_to_cpu(pcr_selection.hash_alg); >> + >> + for (j = 0; j < pcr_selection.size_of_select; j++) >> + if (pcr_selection.pcr_select[j]) >> + break; >> + >> + if (j < pcr_selection.size_of_select) { >> + chip->allocated_banks[nr_alloc_banks] = hash_alg; >> + nr_alloc_banks++; >> + } > > The same comment as before: you should use memchr_inv() here. Ok. Roberto >> + >> sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) + >> sizeof(pcr_selection.size_of_select) + >> pcr_selection.size_of_select; >> marker = marker + sizeof_pcr_selection; >> } >> >> + chip->nr_allocated_banks = nr_alloc_banks; >> out: >> - if (i < ARRAY_SIZE(chip->active_banks)) >> - chip->active_banks[i] = TPM2_ALG_ERROR; >> - >> tpm_buf_destroy(&buf); >> >> return rc; >> -- >> 2.17.1 >> > > /Jarkko >
On Fri, Dec 21, 2018 at 10:40:09AM +0100, Roberto Sassu wrote: > On 12/20/2018 3:55 PM, Jarkko Sakkinen wrote: > > On Thu, Dec 13, 2018 at 11:29:41AM +0100, Roberto Sassu wrote: > > > This patch renames active_banks (member of tpm_chip) to allocated_banks, > > > stores the number of allocated PCR banks in nr_allocated_banks (new member > > > of tpm_chip), and replaces the static array with a pointer to a dynamically > > > allocated array. > > > > > > tpm2_get_pcr_allocation() determines if a PCR bank is allocated by checking > > > the mask in the TPML_PCR_SELECTION structure returned by the TPM for > > > TPM2_Get_Capability(). If a bank is not allocated, the TPM returns that > > > bank in TPML_PCR_SELECTION, with all bits in the mask set to zero. In this > > > case, the bank is not included in chip->allocated_banks, to avoid that TPM > > > driver users unnecessarily calculate a digest for that bank. > > > > > > One PCR bank with algorithm set to SHA1 is always allocated for TPM 1.x. > > > > > > As a consequence of the introduction of nr_allocated_banks, > > > tpm_pcr_extend() does not check anymore if the algorithm stored in tpm_chip > > > is equal to zero. > > > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > > > Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> > > > --- > > > drivers/char/tpm/tpm-chip.c | 1 + > > > drivers/char/tpm/tpm-interface.c | 18 +++++++++-------- > > > drivers/char/tpm/tpm.h | 3 ++- > > > drivers/char/tpm/tpm1-cmd.c | 10 ++++++++++ > > > drivers/char/tpm/tpm2-cmd.c | 34 ++++++++++++++++++++++---------- > > > 5 files changed, 47 insertions(+), 19 deletions(-) > > > > > > diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c > > > index 32db84683c40..ce851c62bb68 100644 > > > --- a/drivers/char/tpm/tpm-chip.c > > > +++ b/drivers/char/tpm/tpm-chip.c > > > @@ -160,6 +160,7 @@ static void tpm_dev_release(struct device *dev) > > > kfree(chip->log.bios_event_log); > > > kfree(chip->work_space.context_buf); > > > kfree(chip->work_space.session_buf); > > > + kfree(chip->allocated_banks); > > > kfree(chip); > > > } > > > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c > > > index d9439f9abe78..7b80919228be 100644 > > > --- a/drivers/char/tpm/tpm-interface.c > > > +++ b/drivers/char/tpm/tpm-interface.c > > > @@ -488,8 +488,7 @@ EXPORT_SYMBOL_GPL(tpm_pcr_read); > > > int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) > > > { > > > int rc; > > > - struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; > > > - u32 count = 0; > > > + struct tpm2_digest *digest_list; > > > int i; > > > chip = tpm_find_get_ops(chip); > > > @@ -497,16 +496,19 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) > > > return -ENODEV; > > > if (chip->flags & TPM_CHIP_FLAG_TPM2) { > > > - memset(digest_list, 0, sizeof(digest_list)); > > > + digest_list = kcalloc(chip->nr_allocated_banks, > > > + sizeof(*digest_list), GFP_KERNEL); > > > + if (!digest_list) > > > + return -ENOMEM; > > > > You could preallocate digest list and place it to struct tpm_chip > > instead of doing it everytime tpm_pcr_extend() called. > > This part will be removed with patch 5/5. Even if it did, it does not make this patch unbroken. /Jarkko
On 12/22/2018 1:03 AM, Jarkko Sakkinen wrote: > On Fri, Dec 21, 2018 at 10:40:09AM +0100, Roberto Sassu wrote: >> On 12/20/2018 3:55 PM, Jarkko Sakkinen wrote: >>> On Thu, Dec 13, 2018 at 11:29:41AM +0100, Roberto Sassu wrote: >>>> This patch renames active_banks (member of tpm_chip) to allocated_banks, >>>> stores the number of allocated PCR banks in nr_allocated_banks (new member >>>> of tpm_chip), and replaces the static array with a pointer to a dynamically >>>> allocated array. >>>> >>>> tpm2_get_pcr_allocation() determines if a PCR bank is allocated by checking >>>> the mask in the TPML_PCR_SELECTION structure returned by the TPM for >>>> TPM2_Get_Capability(). If a bank is not allocated, the TPM returns that >>>> bank in TPML_PCR_SELECTION, with all bits in the mask set to zero. In this >>>> case, the bank is not included in chip->allocated_banks, to avoid that TPM >>>> driver users unnecessarily calculate a digest for that bank. >>>> >>>> One PCR bank with algorithm set to SHA1 is always allocated for TPM 1.x. >>>> >>>> As a consequence of the introduction of nr_allocated_banks, >>>> tpm_pcr_extend() does not check anymore if the algorithm stored in tpm_chip >>>> is equal to zero. >>>> >>>> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> >>>> Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> >>>> --- >>>> drivers/char/tpm/tpm-chip.c | 1 + >>>> drivers/char/tpm/tpm-interface.c | 18 +++++++++-------- >>>> drivers/char/tpm/tpm.h | 3 ++- >>>> drivers/char/tpm/tpm1-cmd.c | 10 ++++++++++ >>>> drivers/char/tpm/tpm2-cmd.c | 34 ++++++++++++++++++++++---------- >>>> 5 files changed, 47 insertions(+), 19 deletions(-) >>>> >>>> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c >>>> index 32db84683c40..ce851c62bb68 100644 >>>> --- a/drivers/char/tpm/tpm-chip.c >>>> +++ b/drivers/char/tpm/tpm-chip.c >>>> @@ -160,6 +160,7 @@ static void tpm_dev_release(struct device *dev) >>>> kfree(chip->log.bios_event_log); >>>> kfree(chip->work_space.context_buf); >>>> kfree(chip->work_space.session_buf); >>>> + kfree(chip->allocated_banks); >>>> kfree(chip); >>>> } >>>> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c >>>> index d9439f9abe78..7b80919228be 100644 >>>> --- a/drivers/char/tpm/tpm-interface.c >>>> +++ b/drivers/char/tpm/tpm-interface.c >>>> @@ -488,8 +488,7 @@ EXPORT_SYMBOL_GPL(tpm_pcr_read); >>>> int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) >>>> { >>>> int rc; >>>> - struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; >>>> - u32 count = 0; >>>> + struct tpm2_digest *digest_list; >>>> int i; >>>> chip = tpm_find_get_ops(chip); >>>> @@ -497,16 +496,19 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) >>>> return -ENODEV; >>>> if (chip->flags & TPM_CHIP_FLAG_TPM2) { >>>> - memset(digest_list, 0, sizeof(digest_list)); >>>> + digest_list = kcalloc(chip->nr_allocated_banks, >>>> + sizeof(*digest_list), GFP_KERNEL); >>>> + if (!digest_list) >>>> + return -ENOMEM; >>> >>> You could preallocate digest list and place it to struct tpm_chip >>> instead of doing it everytime tpm_pcr_extend() called. >> >> This part will be removed with patch 5/5. > > Even if it did, it does not make this patch unbroken. Can two calls to tpm_pcr_extend() be executed at the same time? If yes, the digest list should be protected by a mutex. Roberto > /Jarkko >
On Mon, Jan 07, 2019 at 11:06:33AM +0100, Roberto Sassu wrote: > On 12/22/2018 1:03 AM, Jarkko Sakkinen wrote: > > On Fri, Dec 21, 2018 at 10:40:09AM +0100, Roberto Sassu wrote: > > > On 12/20/2018 3:55 PM, Jarkko Sakkinen wrote: > > > > On Thu, Dec 13, 2018 at 11:29:41AM +0100, Roberto Sassu wrote: > > > > > This patch renames active_banks (member of tpm_chip) to allocated_banks, > > > > > stores the number of allocated PCR banks in nr_allocated_banks (new member > > > > > of tpm_chip), and replaces the static array with a pointer to a dynamically > > > > > allocated array. > > > > > > > > > > tpm2_get_pcr_allocation() determines if a PCR bank is allocated by checking > > > > > the mask in the TPML_PCR_SELECTION structure returned by the TPM for > > > > > TPM2_Get_Capability(). If a bank is not allocated, the TPM returns that > > > > > bank in TPML_PCR_SELECTION, with all bits in the mask set to zero. In this > > > > > case, the bank is not included in chip->allocated_banks, to avoid that TPM > > > > > driver users unnecessarily calculate a digest for that bank. > > > > > > > > > > One PCR bank with algorithm set to SHA1 is always allocated for TPM 1.x. > > > > > > > > > > As a consequence of the introduction of nr_allocated_banks, > > > > > tpm_pcr_extend() does not check anymore if the algorithm stored in tpm_chip > > > > > is equal to zero. > > > > > > > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > > > > > Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> > > > > > --- > > > > > drivers/char/tpm/tpm-chip.c | 1 + > > > > > drivers/char/tpm/tpm-interface.c | 18 +++++++++-------- > > > > > drivers/char/tpm/tpm.h | 3 ++- > > > > > drivers/char/tpm/tpm1-cmd.c | 10 ++++++++++ > > > > > drivers/char/tpm/tpm2-cmd.c | 34 ++++++++++++++++++++++---------- > > > > > 5 files changed, 47 insertions(+), 19 deletions(-) > > > > > > > > > > diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c > > > > > index 32db84683c40..ce851c62bb68 100644 > > > > > --- a/drivers/char/tpm/tpm-chip.c > > > > > +++ b/drivers/char/tpm/tpm-chip.c > > > > > @@ -160,6 +160,7 @@ static void tpm_dev_release(struct device *dev) > > > > > kfree(chip->log.bios_event_log); > > > > > kfree(chip->work_space.context_buf); > > > > > kfree(chip->work_space.session_buf); > > > > > + kfree(chip->allocated_banks); > > > > > kfree(chip); > > > > > } > > > > > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c > > > > > index d9439f9abe78..7b80919228be 100644 > > > > > --- a/drivers/char/tpm/tpm-interface.c > > > > > +++ b/drivers/char/tpm/tpm-interface.c > > > > > @@ -488,8 +488,7 @@ EXPORT_SYMBOL_GPL(tpm_pcr_read); > > > > > int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) > > > > > { > > > > > int rc; > > > > > - struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; > > > > > - u32 count = 0; > > > > > + struct tpm2_digest *digest_list; > > > > > int i; > > > > > chip = tpm_find_get_ops(chip); > > > > > @@ -497,16 +496,19 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) > > > > > return -ENODEV; > > > > > if (chip->flags & TPM_CHIP_FLAG_TPM2) { > > > > > - memset(digest_list, 0, sizeof(digest_list)); > > > > > + digest_list = kcalloc(chip->nr_allocated_banks, > > > > > + sizeof(*digest_list), GFP_KERNEL); > > > > > + if (!digest_list) > > > > > + return -ENOMEM; > > > > > > > > You could preallocate digest list and place it to struct tpm_chip > > > > instead of doing it everytime tpm_pcr_extend() called. > > > > > > This part will be removed with patch 5/5. > > > > Even if it did, it does not make this patch unbroken. > > Can two calls to tpm_pcr_extend() be executed at the same time? > > If yes, the digest list should be protected by a mutex. Good question: the answer is no. Mutex locking is done inside the transmit flow ATM. /Jarkko
On 1/10/2019 6:38 PM, Jarkko Sakkinen wrote: > On Mon, Jan 07, 2019 at 11:06:33AM +0100, Roberto Sassu wrote: >> On 12/22/2018 1:03 AM, Jarkko Sakkinen wrote: >>> On Fri, Dec 21, 2018 at 10:40:09AM +0100, Roberto Sassu wrote: >>>> On 12/20/2018 3:55 PM, Jarkko Sakkinen wrote: >>>>> On Thu, Dec 13, 2018 at 11:29:41AM +0100, Roberto Sassu wrote: >>>>>> This patch renames active_banks (member of tpm_chip) to allocated_banks, >>>>>> stores the number of allocated PCR banks in nr_allocated_banks (new member >>>>>> of tpm_chip), and replaces the static array with a pointer to a dynamically >>>>>> allocated array. >>>>>> >>>>>> tpm2_get_pcr_allocation() determines if a PCR bank is allocated by checking >>>>>> the mask in the TPML_PCR_SELECTION structure returned by the TPM for >>>>>> TPM2_Get_Capability(). If a bank is not allocated, the TPM returns that >>>>>> bank in TPML_PCR_SELECTION, with all bits in the mask set to zero. In this >>>>>> case, the bank is not included in chip->allocated_banks, to avoid that TPM >>>>>> driver users unnecessarily calculate a digest for that bank. >>>>>> >>>>>> One PCR bank with algorithm set to SHA1 is always allocated for TPM 1.x. >>>>>> >>>>>> As a consequence of the introduction of nr_allocated_banks, >>>>>> tpm_pcr_extend() does not check anymore if the algorithm stored in tpm_chip >>>>>> is equal to zero. >>>>>> >>>>>> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> >>>>>> Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> >>>>>> --- >>>>>> drivers/char/tpm/tpm-chip.c | 1 + >>>>>> drivers/char/tpm/tpm-interface.c | 18 +++++++++-------- >>>>>> drivers/char/tpm/tpm.h | 3 ++- >>>>>> drivers/char/tpm/tpm1-cmd.c | 10 ++++++++++ >>>>>> drivers/char/tpm/tpm2-cmd.c | 34 ++++++++++++++++++++++---------- >>>>>> 5 files changed, 47 insertions(+), 19 deletions(-) >>>>>> >>>>>> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c >>>>>> index 32db84683c40..ce851c62bb68 100644 >>>>>> --- a/drivers/char/tpm/tpm-chip.c >>>>>> +++ b/drivers/char/tpm/tpm-chip.c >>>>>> @@ -160,6 +160,7 @@ static void tpm_dev_release(struct device *dev) >>>>>> kfree(chip->log.bios_event_log); >>>>>> kfree(chip->work_space.context_buf); >>>>>> kfree(chip->work_space.session_buf); >>>>>> + kfree(chip->allocated_banks); >>>>>> kfree(chip); >>>>>> } >>>>>> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c >>>>>> index d9439f9abe78..7b80919228be 100644 >>>>>> --- a/drivers/char/tpm/tpm-interface.c >>>>>> +++ b/drivers/char/tpm/tpm-interface.c >>>>>> @@ -488,8 +488,7 @@ EXPORT_SYMBOL_GPL(tpm_pcr_read); >>>>>> int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) >>>>>> { >>>>>> int rc; >>>>>> - struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; >>>>>> - u32 count = 0; >>>>>> + struct tpm2_digest *digest_list; >>>>>> int i; >>>>>> chip = tpm_find_get_ops(chip); >>>>>> @@ -497,16 +496,19 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) >>>>>> return -ENODEV; >>>>>> if (chip->flags & TPM_CHIP_FLAG_TPM2) { >>>>>> - memset(digest_list, 0, sizeof(digest_list)); >>>>>> + digest_list = kcalloc(chip->nr_allocated_banks, >>>>>> + sizeof(*digest_list), GFP_KERNEL); >>>>>> + if (!digest_list) >>>>>> + return -ENOMEM; >>>>> >>>>> You could preallocate digest list and place it to struct tpm_chip >>>>> instead of doing it everytime tpm_pcr_extend() called. >>>> >>>> This part will be removed with patch 5/5. >>> >>> Even if it did, it does not make this patch unbroken. >> >> Can two calls to tpm_pcr_extend() be executed at the same time? >> >> If yes, the digest list should be protected by a mutex. > > Good question: the answer is no. Mutex locking is done inside the > transmit flow ATM. But data are copied before the mutex is locked. Can't a second call overwrite chip->preallocated_digest_list while the first call is still writing it? Roberto > /Jarkko >
On Fri, Jan 11, 2019 at 08:53:00AM +0100, Roberto Sassu wrote: > On 1/10/2019 6:38 PM, Jarkko Sakkinen wrote: > > On Mon, Jan 07, 2019 at 11:06:33AM +0100, Roberto Sassu wrote: > > > On 12/22/2018 1:03 AM, Jarkko Sakkinen wrote: > > > > On Fri, Dec 21, 2018 at 10:40:09AM +0100, Roberto Sassu wrote: > > > > > On 12/20/2018 3:55 PM, Jarkko Sakkinen wrote: > > > > > > On Thu, Dec 13, 2018 at 11:29:41AM +0100, Roberto Sassu wrote: > > > > > > > This patch renames active_banks (member of tpm_chip) to allocated_banks, > > > > > > > stores the number of allocated PCR banks in nr_allocated_banks (new member > > > > > > > of tpm_chip), and replaces the static array with a pointer to a dynamically > > > > > > > allocated array. > > > > > > > > > > > > > > tpm2_get_pcr_allocation() determines if a PCR bank is allocated by checking > > > > > > > the mask in the TPML_PCR_SELECTION structure returned by the TPM for > > > > > > > TPM2_Get_Capability(). If a bank is not allocated, the TPM returns that > > > > > > > bank in TPML_PCR_SELECTION, with all bits in the mask set to zero. In this > > > > > > > case, the bank is not included in chip->allocated_banks, to avoid that TPM > > > > > > > driver users unnecessarily calculate a digest for that bank. > > > > > > > > > > > > > > One PCR bank with algorithm set to SHA1 is always allocated for TPM 1.x. > > > > > > > > > > > > > > As a consequence of the introduction of nr_allocated_banks, > > > > > > > tpm_pcr_extend() does not check anymore if the algorithm stored in tpm_chip > > > > > > > is equal to zero. > > > > > > > > > > > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> > > > > > > > Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> > > > > > > > --- > > > > > > > drivers/char/tpm/tpm-chip.c | 1 + > > > > > > > drivers/char/tpm/tpm-interface.c | 18 +++++++++-------- > > > > > > > drivers/char/tpm/tpm.h | 3 ++- > > > > > > > drivers/char/tpm/tpm1-cmd.c | 10 ++++++++++ > > > > > > > drivers/char/tpm/tpm2-cmd.c | 34 ++++++++++++++++++++++---------- > > > > > > > 5 files changed, 47 insertions(+), 19 deletions(-) > > > > > > > > > > > > > > diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c > > > > > > > index 32db84683c40..ce851c62bb68 100644 > > > > > > > --- a/drivers/char/tpm/tpm-chip.c > > > > > > > +++ b/drivers/char/tpm/tpm-chip.c > > > > > > > @@ -160,6 +160,7 @@ static void tpm_dev_release(struct device *dev) > > > > > > > kfree(chip->log.bios_event_log); > > > > > > > kfree(chip->work_space.context_buf); > > > > > > > kfree(chip->work_space.session_buf); > > > > > > > + kfree(chip->allocated_banks); > > > > > > > kfree(chip); > > > > > > > } > > > > > > > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c > > > > > > > index d9439f9abe78..7b80919228be 100644 > > > > > > > --- a/drivers/char/tpm/tpm-interface.c > > > > > > > +++ b/drivers/char/tpm/tpm-interface.c > > > > > > > @@ -488,8 +488,7 @@ EXPORT_SYMBOL_GPL(tpm_pcr_read); > > > > > > > int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) > > > > > > > { > > > > > > > int rc; > > > > > > > - struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; > > > > > > > - u32 count = 0; > > > > > > > + struct tpm2_digest *digest_list; > > > > > > > int i; > > > > > > > chip = tpm_find_get_ops(chip); > > > > > > > @@ -497,16 +496,19 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) > > > > > > > return -ENODEV; > > > > > > > if (chip->flags & TPM_CHIP_FLAG_TPM2) { > > > > > > > - memset(digest_list, 0, sizeof(digest_list)); > > > > > > > + digest_list = kcalloc(chip->nr_allocated_banks, > > > > > > > + sizeof(*digest_list), GFP_KERNEL); > > > > > > > + if (!digest_list) > > > > > > > + return -ENOMEM; > > > > > > > > > > > > You could preallocate digest list and place it to struct tpm_chip > > > > > > instead of doing it everytime tpm_pcr_extend() called. > > > > > > > > > > This part will be removed with patch 5/5. > > > > > > > > Even if it did, it does not make this patch unbroken. > > > > > > Can two calls to tpm_pcr_extend() be executed at the same time? > > > > > > If yes, the digest list should be protected by a mutex. > > > > Good question: the answer is no. Mutex locking is done inside the > > transmit flow ATM. > > But data are copied before the mutex is locked. Can't a second call > overwrite chip->preallocated_digest_list while the first call is still > writing it? Now I see what you mean. I have patch set on review that would make this more natural to do. Locking can be done now too so that it would work but that would counter-productive, so lets keep the approach that you have. /Jarkko
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index 32db84683c40..ce851c62bb68 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -160,6 +160,7 @@ static void tpm_dev_release(struct device *dev) kfree(chip->log.bios_event_log); kfree(chip->work_space.context_buf); kfree(chip->work_space.session_buf); + kfree(chip->allocated_banks); kfree(chip); } diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index d9439f9abe78..7b80919228be 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -488,8 +488,7 @@ EXPORT_SYMBOL_GPL(tpm_pcr_read); int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) { int rc; - struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; - u32 count = 0; + struct tpm2_digest *digest_list; int i; chip = tpm_find_get_ops(chip); @@ -497,16 +496,19 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) return -ENODEV; if (chip->flags & TPM_CHIP_FLAG_TPM2) { - memset(digest_list, 0, sizeof(digest_list)); + digest_list = kcalloc(chip->nr_allocated_banks, + sizeof(*digest_list), GFP_KERNEL); + if (!digest_list) + return -ENOMEM; - for (i = 0; i < ARRAY_SIZE(chip->active_banks) && - chip->active_banks[i] != TPM2_ALG_ERROR; i++) { - digest_list[i].alg_id = chip->active_banks[i]; + for (i = 0; i < chip->nr_allocated_banks; i++) { + digest_list[i].alg_id = chip->allocated_banks[i]; memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE); - count++; } - rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list); + rc = tpm2_pcr_extend(chip, pcr_idx, chip->nr_allocated_banks, + digest_list); + kfree(digest_list); tpm_put_ops(chip); return rc; } diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index f27d1f38a93d..6b94306ab7c5 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -257,7 +257,8 @@ struct tpm_chip { const struct attribute_group *groups[3]; unsigned int groups_cnt; - u16 active_banks[7]; + u32 nr_allocated_banks; + u16 *allocated_banks; #ifdef CONFIG_ACPI acpi_handle acpi_dev_handle; char ppi_version[TPM_PPI_VERSION_LEN + 1]; diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c index 6f306338953b..0874743ca96d 100644 --- a/drivers/char/tpm/tpm1-cmd.c +++ b/drivers/char/tpm/tpm1-cmd.c @@ -709,6 +709,16 @@ int tpm1_auto_startup(struct tpm_chip *chip) goto out; } + chip->allocated_banks = kcalloc(1, sizeof(*chip->allocated_banks), + GFP_KERNEL); + if (!chip->allocated_banks) { + rc = -ENOMEM; + goto out; + } + + chip->allocated_banks[0] = TPM2_ALG_SHA1; + chip->nr_allocated_banks = 1; + return rc; out: if (rc > 0) diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index a6bec13afa69..245669a7aba5 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -234,7 +234,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, u32 count, int i; int j; - if (count > ARRAY_SIZE(chip->active_banks)) + if (count > chip->nr_allocated_banks) return -EINVAL; rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND); @@ -825,11 +825,14 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) void *marker; void *end; void *pcr_select_offset; - unsigned int count; u32 sizeof_pcr_selection; + u32 nr_possible_banks; + u32 nr_alloc_banks = 0; + u16 hash_alg; u32 rsp_len; int rc; int i = 0; + int j; rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY); if (rc) @@ -844,11 +847,14 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) if (rc) goto out; - count = be32_to_cpup( + nr_possible_banks = be32_to_cpup( (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]); - if (count > ARRAY_SIZE(chip->active_banks)) { - rc = -ENODEV; + chip->allocated_banks = kcalloc(nr_possible_banks, + sizeof(*chip->allocated_banks), + GFP_KERNEL); + if (!chip->allocated_banks) { + rc = -ENOMEM; goto out; } @@ -857,7 +863,7 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) rsp_len = be32_to_cpup((__be32 *)&buf.data[2]); end = &buf.data[rsp_len]; - for (i = 0; i < count; i++) { + 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) { @@ -866,17 +872,25 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) } memcpy(&pcr_selection, marker, sizeof(pcr_selection)); - chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg); + hash_alg = be16_to_cpu(pcr_selection.hash_alg); + + for (j = 0; j < pcr_selection.size_of_select; j++) + if (pcr_selection.pcr_select[j]) + break; + + if (j < pcr_selection.size_of_select) { + chip->allocated_banks[nr_alloc_banks] = hash_alg; + nr_alloc_banks++; + } + sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) + sizeof(pcr_selection.size_of_select) + pcr_selection.size_of_select; marker = marker + sizeof_pcr_selection; } + chip->nr_allocated_banks = nr_alloc_banks; out: - if (i < ARRAY_SIZE(chip->active_banks)) - chip->active_banks[i] = TPM2_ALG_ERROR; - tpm_buf_destroy(&buf); return rc;