KEYS: trusted: correctly initialize digests and fix locking issue

Commit 0b6cf6b97b7e ("tpm: pass an array of tpm_extend_digest structures to
tpm_pcr_extend()") modifies tpm_pcr_extend() to accept a digest for each
PCR bank. After modification, tpm_pcr_extend() expects that digests are
passed in the same order as the algorithms set in chip->allocated_banks.

This patch fixes two issues introduced in the last iterations of the patch
set: missing initialization of the TPM algorithm ID in the tpm_digest
structures passed to tpm_pcr_extend() by the trusted key module, and
unreleased locks in the TPM driver due to returning from tpm_pcr_extend()
without calling tpm_put_ops().

Cc: stable@vger.kernel.org
Fixes: 0b6cf6b97b7e ("tpm: pass an array of tpm_extend_digest structures to tpm_pcr_extend()")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Suggested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

1 files changed, 9 insertions, 5 deletions

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 1b4f95c13e00..d9ace5480665 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -320,18 +320,22 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
 	if (!chip)
 		return -ENODEV;
 
-	for (i = 0; i < chip->nr_allocated_banks; i++)
-		if (digests[i].alg_id != chip->allocated_banks[i].alg_id)
-			return -EINVAL;
+	for (i = 0; i < chip->nr_allocated_banks; i++) {
+		if (digests[i].alg_id != chip->allocated_banks[i].alg_id) {
+			rc = EINVAL;
+			goto out;
+		}
+	}
 
 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
 		rc = tpm2_pcr_extend(chip, pcr_idx, digests);
-		tpm_put_ops(chip);
-		return rc;
+		goto out;
 	}
 
 	rc = tpm1_pcr_extend(chip, pcr_idx, digests[0].digest,
 			     "attempting extend a PCR value");
+
+out:
 	tpm_put_ops(chip);
 	return rc;
 }