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SubjectRe: [PATCH v9 6/6] tpm: pass an array of tpm_extend_digest structures to tpm_pcr_extend()
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Hi Roberto,

Sorry for the delayed review.  A few comments inline below, minor
suggestions.

> diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
> index cc12f3449a72..e6b2dcb0846a 100644
> --- a/security/integrity/ima/ima.h
> +++ b/security/integrity/ima/ima.h
> @@ -56,6 +56,7 @@ extern int ima_policy_flag;
> extern int ima_hash_algo;
> extern int ima_appraise;
> extern struct tpm_chip *ima_tpm_chip;
> +extern struct tpm_digest *digests;
>
> /* IMA event related data */
> struct ima_event_data {
> diff --git a/security/integrity/ima/ima_init.c b/security/integrity/ima/ima_init.c
> index 6bb42a9c5e47..296a965b11ef 100644
> --- a/security/integrity/ima/ima_init.c
> +++ b/security/integrity/ima/ima_init.c
> @@ -27,6 +27,7 @@
> /* name for boot aggregate entry */
> static const char boot_aggregate_name[] = "boot_aggregate";
> struct tpm_chip *ima_tpm_chip;
> +struct tpm_digest *digests;

"digests" is used in the new ima_init_digests() and in
ima_pcr_extend().  It's nice that the initialization routines are
grouped together here in ima_init.c, but wouldn't it better to define
"digests" in ima_queued.c, where it is currently being used?
 "digests" could then be defined as static.

>
> /* Add the boot aggregate to the IMA measurement list and extend
> * the PCR register.
> @@ -104,6 +105,24 @@ void __init ima_load_x509(void)
> }
> #endif
>
> +int __init ima_init_digests(void)
> +{
> + int i;
> +
> + if (!ima_tpm_chip)
> + return 0;
> +
> + digests = kcalloc(ima_tpm_chip->nr_allocated_banks, sizeof(*digests),
> + GFP_NOFS);
> + if (!digests)
> + return -ENOMEM;
> +
> + for (i = 0; i < ima_tpm_chip->nr_allocated_banks; i++)
> + digests[i].alg_id = ima_tpm_chip->allocated_banks[i].alg_id;
> +
> + return 0;
> +}
> +
> int __init ima_init(void)
> {
> int rc;
> @@ -125,6 +144,9 @@ int __init ima_init(void)
>
> ima_load_kexec_buffer();
>
> + rc = ima_init_digests();

Ok. Getting the tpm chip is at the beginning of this function.
 Deferring allocating "digests" to here, avoids having to free memory
on failure.

ima_load_kexec_buffer() restores prior measurements, but doesn't
extend the TPM.  For anyone reading the code, a short comment above
ima_load_kexec_buffer() would make sense.

Mimi
   
> + if (rc != 0)
> + return rc;
> rc = ima_add_boot_aggregate(); /* boot aggregate must be first entry */
> if (rc != 0)
> return rc;
> diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c
> index 0e41dc1df1d4..719e88ca58f6 100644
> --- a/security/integrity/ima/ima_queue.c
> +++ b/security/integrity/ima/ima_queue.c
> @@ -140,11 +140,15 @@ unsigned long ima_get_binary_runtime_size(void)
> static int ima_pcr_extend(const u8 *hash, int pcr)
> {
> int result = 0;
> + int i;
>
> if (!ima_tpm_chip)
> return result;
>
> - result = tpm_pcr_extend(ima_tpm_chip, pcr, hash);
> + for (i = 0; i < ima_tpm_chip->nr_allocated_banks; i++)
> + memcpy(digests[i].digest, hash, TPM_DIGEST_SIZE);
> +
> + result = tpm_pcr_extend(ima_tpm_chip, pcr, digests);
> if (result != 0)
> pr_err("Error Communicating to TPM chip, result: %d\n", result);
> return result;
>

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