From patchwork Tue Jun 7 23:02:00 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 9162803 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id BDEAC60831 for ; Tue, 7 Jun 2016 23:03:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id AFB772836E for ; Tue, 7 Jun 2016 23:03:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A4D2628370; Tue, 7 Jun 2016 23:03:37 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5B25B2836F for ; Tue, 7 Jun 2016 23:03:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754744AbcFGXCo (ORCPT ); Tue, 7 Jun 2016 19:02:44 -0400 Received: from mga11.intel.com ([192.55.52.93]:62246 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754489AbcFGXCm (ORCPT ); Tue, 7 Jun 2016 19:02:42 -0400 Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga102.fm.intel.com with ESMTP; 07 Jun 2016 16:02:41 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.26,436,1459839600"; d="scan'208";a="997311882" Received: from raunstru-mobl1.ger.corp.intel.com (HELO localhost) ([10.252.10.27]) by fmsmga002.fm.intel.com with ESMTP; 07 Jun 2016 16:02:37 -0700 From: Jarkko Sakkinen To: Peter Huewe Cc: linux-security-module@vger.kernel.org, Jarkko Sakkinen , stable@vger.kernel.org, Marcel Selhorst , Jason Gunthorpe , tpmdd-devel@lists.sourceforge.net (moderated list:TPM DEVICE DRIVER), linux-kernel@vger.kernel.org (open list) Subject: [PATCH 1/3] tpm_crb: fix crb_req_canceled behavior Date: Wed, 8 Jun 2016 02:02:00 +0300 Message-Id: <1465340522-1112-2-git-send-email-jarkko.sakkinen@linux.intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1465340522-1112-1-git-send-email-jarkko.sakkinen@linux.intel.com> References: <1465340522-1112-1-git-send-email-jarkko.sakkinen@linux.intel.com> Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: X-Virus-Scanned: ClamAV using ClamSMTP 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)