From patchwork Thu Jun 25 14:46:47 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Amir Mizinski X-Patchwork-Id: 11625503 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5F6DE60D for ; Thu, 25 Jun 2020 14:48:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 479FB206C0 for ; Thu, 25 Jun 2020 14:48:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405570AbgFYOs1 (ORCPT ); Thu, 25 Jun 2020 10:48:27 -0400 Received: from 212.199.177.27.static.012.net.il ([212.199.177.27]:51444 "EHLO herzl.nuvoton.co.il" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2405522AbgFYOsM (ORCPT ); Thu, 25 Jun 2020 10:48:12 -0400 Received: from taln60.nuvoton.co.il (ntil-fw [212.199.177.25]) by herzl.nuvoton.co.il (8.13.8/8.13.8) with ESMTP id 05PEloXb015294; Thu, 25 Jun 2020 17:47:51 +0300 Received: by taln60.nuvoton.co.il (Postfix, from userid 10140) id F2620639BE; Thu, 25 Jun 2020 17:47:50 +0300 (IDT) From: amirmizi6@gmail.com To: Eyal.Cohen@nuvoton.com, jarkko.sakkinen@linux.intel.com, oshrialkoby85@gmail.com, alexander.steffen@infineon.com, robh+dt@kernel.org, "benoit.houyere@st.com--to=mark.rutland"@arm.com, peterhuewe@gmx.de, christophe-h.richard@st.com, jgg@ziepe.ca, arnd@arndb.de, gregkh@linuxfoundation.org Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, oshri.alkoby@nuvoton.com, tmaimon77@gmail.com, gcwilson@us.ibm.com, kgoldman@us.ibm.com, Dan.Morav@nuvoton.com, oren.tanami@nuvoton.com, shmulik.hager@nuvoton.com, amir.mizinski@nuvoton.com, Amir Mizinski , Benoit Houyere Subject: [PATCH v12 7/9] tpm: tpm_tis: verify TPM_STS register is valid after locality request Date: Thu, 25 Jun 2020 17:46:47 +0300 Message-Id: <20200625144650.269719-8-amirmizi6@gmail.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20200625144650.269719-1-amirmizi6@gmail.com> References: <20200625144650.269719-1-amirmizi6@gmail.com> MIME-Version: 1.0 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: Amir Mizinski Issue could result when the TPM does not update TPM_STS register after a locality request (TPM_STS Initial value = 0xFF) and a TPM_STS register read occurs (tpm_tis_status(chip)). Checking the next condition("if ((status & TPM_STS_COMMAND_READY) == 0)"), the status will be at 0xFF and will be considered, wrongly, in "Ready" state (by checking only one bit). However, at this moment the TPM is, in fact, in "Idle" state and remains in "Idle" state because "tpm_tis_ready(chip);" was not executed. Suggested-by: Benoit Houyere Signed-off-by: Amir Mizinski --- drivers/char/tpm/tpm_tis_core.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index a38465f..b876db2 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -221,8 +221,14 @@ static int request_locality(struct tpm_chip *chip, int l) } else { /* wait for burstcount */ do { - if (check_locality(chip, l)) + if (check_locality(chip, l)) { + if (wait_for_tpm_stat(chip, TPM_STS_GO, 0, + chip->timeout_c, + &priv->int_queue, + false) < 0) + return -ETIME; return l; + } tpm_msleep(TPM_TIMEOUT); } while (time_before(jiffies, stop)); }