[PATCH] KEYS: trusted: Fix TPM reservation for seal/unseal

From: James Bottomley <James.Bottomley@HansenPartnership.com>
To: linux-integrity@vger.kernel.org, keyrings@vger.kernel.org
Cc: jarkko@kernel.org, Mimi Zohar <zohar@linux.ibm.com>
Subject: [PATCH] KEYS: trusted: Fix TPM reservation for seal/unseal
Date: Wed, 21 Apr 2021 15:42:47 -0700	[thread overview]
Message-ID: <30acbe05a0569bd3b3a9f968c4863e1f42b6d320.camel@HansenPartnership.com> (raw)

The original patch 8c657a0590de ("KEYS: trusted: Reserve TPM for seal
and unseal operations") was correct on the mailing list:

https://lore.kernel.org/linux-integrity/20210128235621.127925-4-jarkko@kernel.org/

But somehow got rebased so that the tpm_try_get_ops() in
tpm2_seal_trusted() got lost.  This causes an imbalanced put of the
TPM ops and causes oopses on TIS based hardware.

This fix puts back the lost tpm_try_get_ops()

Fixes: 8c657a0590de ("KEYS: trusted: Reserve TPM for seal and unseal operations")
Reported-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
---
 security/keys/trusted-keys/trusted_tpm2.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index d225ad140960..617fabd4d913 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -248,7 +248,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
 	if (!options->keyhandle)
 		return -EINVAL;
 
-	rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
+	rc = tpm_try_get_ops(chip);
 	if (rc)
 		return rc;
 
-- 
2.26.2


