From patchwork Tue Oct 13 00:28:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 11834735 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 1230469EF for ; Tue, 13 Oct 2020 02:45:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0335D20678 for ; Tue, 13 Oct 2020 02:45:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726919AbgJMA22 (ORCPT ); Mon, 12 Oct 2020 20:28:28 -0400 Received: from mga07.intel.com ([134.134.136.100]:8540 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726564AbgJMA22 (ORCPT ); Mon, 12 Oct 2020 20:28:28 -0400 IronPort-SDR: 2aBZ6ae/1jTjspiGyqk+dF0PAUe4z0bKkUun/uWsBJzm8ihSWUAa0AGNuOzseXi8tF4ul5cXaQ ehPuhBz/Z/iQ== X-IronPort-AV: E=McAfee;i="6000,8403,9772"; a="230002298" X-IronPort-AV: E=Sophos;i="5.77,368,1596524400"; d="scan'208";a="230002298" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Oct 2020 17:28:27 -0700 IronPort-SDR: Bu4FvpltcYE9xk6Hvso9hT15D9oWCNGy5e/qOvb5X9q91LT1sAomgza7nohR1vgevo4eRkYxov QDXBDKPpD9hA== X-IronPort-AV: E=Sophos;i="5.77,368,1596524400"; d="scan'208";a="299438052" Received: from lusin-mobl1.ger.corp.intel.com (HELO localhost) ([10.252.53.81]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Oct 2020 17:28:23 -0700 From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: David Howells , Mimi Zohar , James Bottomley , Jarkko Sakkinen , stable@vger.kernel.org, "James E.J. Bottomley" , Kent Yoder , James Morris , "Serge E. Hallyn" , David Safford , "H. Peter Anvin" , keyrings@vger.kernel.org (open list:KEYS-TRUSTED), linux-security-module@vger.kernel.org (open list:SECURITY SUBSYSTEM), linux-kernel@vger.kernel.org (open list) Subject: [PATCH v3 1/3] KEYS: trusted: Fix incorrect handling of tpm_get_random() Date: Tue, 13 Oct 2020 03:28:13 +0300 Message-Id: <20201013002815.40256-2-jarkko.sakkinen@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201013002815.40256-1-jarkko.sakkinen@linux.intel.com> References: <20201013002815.40256-1-jarkko.sakkinen@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org When tpm_get_random() was introduced, it defined the following API for the return value: 1. A positive value tells how many bytes of random data was generated. 2. A negative value on error. However, in the call sites the API was used incorrectly, i.e. as it would only return negative values and otherwise zero. Returning he positive read counts to the user space does not make any possible sense. Fix this by returning -EIO when tpm_get_random() returns a positive value. Fixes: 41ab999c80f1 ("tpm: Move tpm_get_random api into the TPM device driver") Cc: stable@vger.kernel.org Cc: Mimi Zohar Cc: "James E.J. Bottomley" Cc: David Howells Cc: Kent Yoder Signed-off-by: Jarkko Sakkinen --- security/keys/trusted-keys/trusted_tpm1.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c index b9fe02e5f84f..c7b1701cdac5 100644 --- a/security/keys/trusted-keys/trusted_tpm1.c +++ b/security/keys/trusted-keys/trusted_tpm1.c @@ -403,9 +403,12 @@ static int osap(struct tpm_buf *tb, struct osapsess *s, int ret; ret = tpm_get_random(chip, ononce, TPM_NONCE_SIZE); - if (ret != TPM_NONCE_SIZE) + if (ret < 0) return ret; + if (ret != TPM_NONCE_SIZE) + return -EIO; + tpm_buf_reset(tb, TPM_TAG_RQU_COMMAND, TPM_ORD_OSAP); tpm_buf_append_u16(tb, type); tpm_buf_append_u32(tb, handle); @@ -496,8 +499,12 @@ static int tpm_seal(struct tpm_buf *tb, uint16_t keytype, goto out; ret = tpm_get_random(chip, td->nonceodd, TPM_NONCE_SIZE); + if (ret < 0) + return ret; + if (ret != TPM_NONCE_SIZE) - goto out; + return -EIO; + ordinal = htonl(TPM_ORD_SEAL); datsize = htonl(datalen); pcrsize = htonl(pcrinfosize); @@ -601,9 +608,12 @@ static int tpm_unseal(struct tpm_buf *tb, ordinal = htonl(TPM_ORD_UNSEAL); ret = tpm_get_random(chip, nonceodd, TPM_NONCE_SIZE); + if (ret < 0) + return ret; + if (ret != TPM_NONCE_SIZE) { pr_info("trusted_key: tpm_get_random failed (%d)\n", ret); - return ret; + return -EIO; } ret = TSS_authhmac(authdata1, keyauth, TPM_NONCE_SIZE, enonce1, nonceodd, cont, sizeof(uint32_t), @@ -1013,8 +1023,12 @@ static int trusted_instantiate(struct key *key, case Opt_new: key_len = payload->key_len; ret = tpm_get_random(chip, payload->key, key_len); + if (ret < 0) + goto out; + if (ret != key_len) { pr_info("trusted_key: key_create failed (%d)\n", ret); + ret = -EIO; goto out; } if (tpm2)