From patchwork Fri Jun 3 11:18:41 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 629769 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.sourceforge.net (lists.sourceforge.net [216.34.181.88]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3rLhSF6B36z9t5l for ; Fri, 3 Jun 2016 21:19:09 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=sfs-ml-3.v29.ch3.sourceforge.com) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1b8n80-0002Vf-91; Fri, 03 Jun 2016 11:19:00 +0000 Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1b8n7y-0002Va-Oe for tpmdd-devel@lists.sourceforge.net; Fri, 03 Jun 2016 11:18:58 +0000 X-ACL-Warn: Received: from mga11.intel.com ([192.55.52.93]) by sog-mx-4.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1b8n7t-0001v1-KZ for tpmdd-devel@lists.sourceforge.net; Fri, 03 Jun 2016 11:18:58 +0000 Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga102.fm.intel.com with ESMTP; 03 Jun 2016 04:18:47 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.26,411,1459839600"; d="scan'208";a="115441173" Received: from ajamart-mobl.ger.corp.intel.com (HELO localhost) ([10.252.31.198]) by fmsmga004.fm.intel.com with ESMTP; 03 Jun 2016 04:18:44 -0700 From: Jarkko Sakkinen To: Peter Huewe Date: Fri, 3 Jun 2016 14:18:41 +0300 Message-Id: <1464952721-7848-1-git-send-email-jarkko.sakkinen@linux.intel.com> X-Mailer: git-send-email 2.7.4 X-Spam-Score: -1.4 (-) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.4 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain X-Headers-End: 1b8n7t-0001v1-KZ Cc: open list , stable@vger.kernel.org, linux-security-module@vger.kernel.org, "moderated list:TPM DEVICE DRIVER" Subject: [tpmdd-devel] [PATCH] tpm_crb: fix crb_req_canceled behavior X-BeenThere: tpmdd-devel@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: Tpm Device Driver maintainance List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: tpmdd-devel-bounces@lists.sourceforge.net The req_canceled() callback is used by tpm_transmit() periodically to check whether the request has been canceled while it is receiving a response from the TPM. The TPM_CRB_CTRL_CANCEL register was cleared already in the crb_cancel callback, which has two consequences: * Cancel might not happen. * req_canceled() always returns zero. A better place to clear the register is when starting to send a new command. The behavior of TPM_CRB_CTRL_CANCEL is described in the section 5.5.3.6 of the PTP specification. CC: stable@vger.kernel.org Fixes: 30fc8d138e91 ("tpm: TPM 2.0 CRB Interface") Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/tpm_crb.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c index 1547636..b4d46ae 100644 --- a/drivers/char/tpm/tpm_crb.c +++ b/drivers/char/tpm/tpm_crb.c @@ -142,6 +142,11 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len) struct crb_priv *priv = dev_get_drvdata(&chip->dev); int rc = 0; + /* Zero the cancel register so that the next command will not get + * canceled. + */ + iowrite32(0, &priv->cca->cancel); + if (len > ioread32(&priv->cca->cmd_size)) { dev_err(&chip->dev, "invalid command count value %x %zx\n", @@ -175,8 +180,6 @@ static void crb_cancel(struct tpm_chip *chip) if ((priv->flags & CRB_FL_ACPI_START) && crb_do_acpi_start(chip)) dev_err(&chip->dev, "ACPI Start failed\n"); - - iowrite32(0, &priv->cca->cancel); } static bool crb_req_canceled(struct tpm_chip *chip, u8 status)