On 5/30/2017 5:35 AM, Mimi Zohar wrote:

On Fri, 2017-05-05 at 16:21 +0200, Roberto Sassu wrote:

quoted

pcrlock() has been modified to pass the correct arguments
to tpm_pcr_extend(): the pointer of a tpm2_digest structure containing
a random value generated by tpm_get_random() and the size of the array (1).

If the number of arguments is wrong, that means the patch that
introduced the change is not bi-sect safe.  (This comment is
applicable to patch 5/5 too.)

Jarkko (the TPM driver maintainer) asked me to not introduce
a new function to pass multiple digests, but to modify
the parameters of tpm_pcr_extend().

Roberto

Mimi

quoted

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
---
 security/keys/trusted.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/security/keys/trusted.c b/security/keys/trusted.c
index 2ae31c5..3eb89e6 100644
--- a/security/keys/trusted.c
+++ b/security/keys/trusted.c

@@ -377,15 +377,15 @@ static int trusted_tpm_send(const u32 chip_num, unsigned char *cmd,
  */
 static int pcrlock(const int pcrnum)
 {
-	unsigned char hash[SHA1_DIGEST_SIZE];
+	struct tpm2_digest digestarg = {.alg_id = TPM2_ALG_SHA1};
 	int ret;

 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
-	ret = tpm_get_random(TPM_ANY_NUM, hash, SHA1_DIGEST_SIZE);
+	ret = tpm_get_random(TPM_ANY_NUM, digestarg.digest, SHA1_DIGEST_SIZE);
 	if (ret != SHA1_DIGEST_SIZE)
 		return ret;
-	return tpm_pcr_extend(TPM_ANY_NUM, pcrnum, hash) ? -EINVAL : 0;
+	return tpm_pcr_extend(TPM_ANY_NUM, pcrnum, 1, &digestarg) ? -EINVAL : 0;
 }

 /*

--
To unsubscribe from this list: send the line "unsubscribe linux-security-module" in
the body of a message to majordomo at vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html