[PATCH 4.5 198/200] tpm: fix: set continueSession attribute for the unseal operation

Greg Kroah-Hartman
2016-05-03T00:54:49Z

From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

commit c0b5eed110dcf520aadafefbcc40658cbdd18b95 upstream.

It's better to set the continueSession attribute for the unseal
operation so that the session object is not removed as a side-effect
when the operation is successful. Since a user process created the
session, it should be also decide when the session is destroyed.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Fixes: 5beb0c435b ("keys, trusted: seal with a TPM2 authorization policy")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/char/tpm/tpm2-cmd.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -20,7 +20,11 @@
#include <keys/trusted-type.h>

enum tpm2_object_attributes {
- TPM2_ATTR_USER_WITH_AUTH = BIT(6),
+ TPM2_OA_USER_WITH_AUTH = BIT(6),
+};
+
+enum tpm2_session_attributes {
+ TPM2_SA_CONTINUE_SESSION = BIT(0),
};

struct tpm2_startup_in {
@@ -489,7 +493,7 @@ int tpm2_seal_trusted(struct tpm_chip *c
tpm_buf_append(&buf, options->policydigest,
options->policydigest_len);
} else {
- tpm_buf_append_u32(&buf, TPM2_ATTR_USER_WITH_AUTH);
+ tpm_buf_append_u32(&buf, TPM2_OA_USER_WITH_AUTH);
tpm_buf_append_u16(&buf, 0);
}

@@ -627,7 +631,7 @@ static int tpm2_unseal(struct tpm_chip *
options->policyhandle ?
options->policyhandle : TPM2_RS_PW,
NULL /* nonce */, 0,
- 0 /* session_attributes */,
+ TPM2_SA_CONTINUE_SESSION,
options->blobauth /* hmac */,
TPM_DIGEST_SIZE);