[PATCH] tpm: vtpm_proxy: Do not access host's event log

From: Stefan Berger <stefanb-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
To: jarkko.sakkinen-VuQAYsv1563Yd54FQh9/CA@public.gmane.org,
	tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org,
	nayna-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org
Subject: [PATCH] tpm: vtpm_proxy: Do not access host's event log
Date: Wed, 16 Nov 2016 09:24:05 -0500	[thread overview]
Message-ID: <1479306245-14456-1-git-send-email-stefanb@linux.vnet.ibm.com> (raw)

The virtual TPM driver must not access the hosts's event log,
otherwise we get crashes from that.

Signed-off-by: Stefan Berger <stefanb-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
---
 drivers/char/tpm/tpm_eventlog.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/char/tpm/tpm_eventlog.c b/drivers/char/tpm/tpm_eventlog.c
index fb603a7..e0abf40 100644
--- a/drivers/char/tpm/tpm_eventlog.c
+++ b/drivers/char/tpm/tpm_eventlog.c
@@ -369,6 +369,9 @@ static int tpm_read_log(struct tpm_chip *chip)
 {
 	int rc;
 
+	if (chip->flags & TPM_CHIP_FLAG_VIRTUAL)
+		return -EFAULT;
+
 	if (chip->log.bios_event_log != NULL) {
 		dev_dbg(&chip->dev,
 			"%s: ERROR - event log already initialized\n",
-- 
2.4.3


------------------------------------------------------------------------------
