From patchwork Wed Jan 16 21:23:33 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 10766963 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4510413B4 for ; Wed, 16 Jan 2019 21:24:50 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 32D662EEE9 for ; Wed, 16 Jan 2019 21:24:50 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 26CBB2F694; Wed, 16 Jan 2019 21:24:50 +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 D14092F67A for ; Wed, 16 Jan 2019 21:24:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729747AbfAPVYs (ORCPT ); Wed, 16 Jan 2019 16:24:48 -0500 Received: from mga17.intel.com ([192.55.52.151]:54867 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729670AbfAPVYl (ORCPT ); Wed, 16 Jan 2019 16:24:41 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Jan 2019 13:24:40 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,487,1539673200"; d="scan'208";a="135247850" Received: from lhaqq1-mobl2.amr.corp.intel.com (HELO localhost) ([10.249.254.231]) by fmsmga002.fm.intel.com with ESMTP; 16 Jan 2019 13:24:35 -0800 From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: linux-security-module@vger.kernel.org, Peter Huewe , Jason Gunthorpe , Tomas Winkler , Tadeusz Struk , Stefan Berger , Nayna Jain , Jarkko Sakkinen , James Bottomley , stable@vger.kernel.org Subject: [PATCH v10 08/17] tpm: call tpm2_flush_space() on error in tpm_try_transmit() Date: Wed, 16 Jan 2019 23:23:33 +0200 Message-Id: <20190116212342.24524-9-jarkko.sakkinen@linux.intel.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190116212342.24524-1-jarkko.sakkinen@linux.intel.com> References: <20190116212342.24524-1-jarkko.sakkinen@linux.intel.com> MIME-Version: 1.0 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: X-Virus-Scanned: ClamAV using ClamSMTP Always call tpm2_flush_space() on failure in tpm_try_transmit() so that the volatile memory of the TPM gets cleared. If /dev/tpm0 does not have sufficient permissions (usually it has), this could lead to the leakage of TPM objects. Through /dev/tpmrm0 this issue does not raise any new security concerns. Cc: James Bottomley Cc: stable@vger.kernel.org Fixes: 745b361e989a ("tpm:tpm: infrastructure for TPM spaces") Signed-off-by: Jarkko Sakkinen Tested-by: Stefan Berger --- drivers/char/tpm/tpm-interface.c | 29 ++++++++++++----------------- drivers/char/tpm/tpm.h | 1 + drivers/char/tpm/tpm2-space.c | 2 +- 3 files changed, 14 insertions(+), 18 deletions(-) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 689d07e67643..2c409d19a9b9 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -220,14 +220,14 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, struct tpm_space *space, rc = tpm2_prepare_space(chip, space, ordinal, buf); if (rc) - goto out; + goto out_idle; rc = chip->ops->send(chip, buf, count); if (rc < 0) { if (rc != -EPIPE) dev_err(&chip->dev, "%s: tpm_send: error %d\n", __func__, rc); - goto out; + goto out_space; } if (chip->flags & TPM_CHIP_FLAG_IRQ) @@ -243,7 +243,7 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, struct tpm_space *space, if (chip->ops->req_canceled(chip, status)) { dev_err(&chip->dev, "Operation Canceled\n"); rc = -ECANCELED; - goto out; + goto out_space; } tpm_msleep(TPM_TIMEOUT_POLL); @@ -253,28 +253,23 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, struct tpm_space *space, chip->ops->cancel(chip); dev_err(&chip->dev, "Operation Timed out\n"); rc = -ETIME; - goto out; + goto out_space; out_recv: len = chip->ops->recv(chip, buf, bufsiz); if (len < 0) { rc = len; - dev_err(&chip->dev, - "tpm_transmit: tpm_recv: error %d\n", rc); - goto out; - } else if (len < TPM_HEADER_SIZE) { + dev_err(&chip->dev, "tpm_transmit: tpm_recv: error %d\n", rc); + } else if (len < TPM_HEADER_SIZE || len != be32_to_cpu(header->length)) rc = -EFAULT; - goto out; - } - if (len != be32_to_cpu(header->length)) { - rc = -EFAULT; - goto out; - } - - rc = tpm2_commit_space(chip, space, ordinal, buf, &len); +out_space: + if (rc) + tpm2_flush_space(chip); + else + rc = tpm2_commit_space(chip, space, ordinal, buf, &len); -out: +out_idle: /* may fail but do not override previous error value in rc */ tpm_go_idle(chip, flags); diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 1454ef19d2f4..6eb67ccad2a3 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -576,6 +576,7 @@ int tpm2_probe(struct tpm_chip *chip); int tpm2_find_cc(struct tpm_chip *chip, u32 cc); int tpm2_init_space(struct tpm_space *space); void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space); +void tpm2_flush_space(struct tpm_chip *chip); int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc, u8 *cmd); int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space, diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c index 39cb3915771e..5d6487575074 100644 --- a/drivers/char/tpm/tpm2-space.c +++ b/drivers/char/tpm/tpm2-space.c @@ -162,7 +162,7 @@ static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf, return 0; } -static void tpm2_flush_space(struct tpm_chip *chip) +void tpm2_flush_space(struct tpm_chip *chip) { struct tpm_space *space = &chip->work_space; int i;