linux-kernel - [PATCH 5.4 262/340] tpm_tis: Fix check_locality for correct locality acquisition

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon,  1 Mar 2021 17:13:26 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, stable@....kernel.org,
        James Bottomley <James.Bottomley@...senPartnership.com>,
        Jerry Snitselaar <jsnitsel@...hat.com>,
        Jarkko Sakkinen <jarkko@...nel.org>
Subject: [PATCH 5.4 262/340] tpm_tis: Fix check_locality for correct locality acquisition

From: James Bottomley <James.Bottomley@...senPartnership.com>

commit 3d9ae54af1d02a7c0edc55c77d7df2b921e58a87 upstream.

The TPM TIS specification says the TPM signals the acquisition of locality
when the TMP_ACCESS_REQUEST_USE bit goes to one *and* the
TPM_ACCESS_REQUEST_USE bit goes to zero.  Currently we only check the
former not the latter, so check both.  Adding the check on
TPM_ACCESS_REQUEST_USE should fix the case where the locality is
re-requested before the TPM has released it.  In this case the locality may
get released briefly before it is reacquired, which causes all sorts of
problems. However, with the added check, TPM_ACCESS_REQUEST_USE should
remain 1 until the second request for the locality is granted.

Cc: stable@....kernel.org
Fixes: 27084efee0c3 ("[PATCH] tpm: driver for next generation TPM chips")
Signed-off-by: James Bottomley <James.Bottomley@...senPartnership.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@...hat.com>
Signed-off-by: Jarkko Sakkinen <jarkko@...nel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/char/tpm/tpm_tis_core.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -125,7 +125,8 @@ static bool check_locality(struct tpm_ch
 	if (rc < 0)
 		return false;
 
-	if ((access & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
+	if ((access & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID
+		       | TPM_ACCESS_REQUEST_USE)) ==
 	    (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) {
 		priv->locality = l;
 		return true;