Messages in this thread | | | Subject | Re: [PATCH v7 1/5] tpm: dynamically allocate the allocated_banks array | From | Roberto Sassu <> | Date | Fri, 21 Dec 2018 10:40:09 +0100 |
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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 >
-- HUAWEI TECHNOLOGIES Duesseldorf GmbH, HRB 56063 Managing Director: Bo PENG, Jian LI, Yanli SHI
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