From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 929E6C4338F for ; Tue, 27 Jul 2021 02:58:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 686EB60FF4 for ; Tue, 27 Jul 2021 02:58:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234422AbhG0CSD (ORCPT ); Mon, 26 Jul 2021 22:18:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:42156 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234410AbhG0CSD (ORCPT ); Mon, 26 Jul 2021 22:18:03 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D78B460FEE; Tue, 27 Jul 2021 02:58:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1627354711; bh=D7jyy3lazrgfTZyaTB4BgIHxwFeOv1IymHhq8hiVd6U=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cRj5czzYT0B8Rs3pS9KNkyps8ctAbVF3UVgWE8niEpqntkQ4ysSl8FRLhb9ojA7Cm 5+/bBBJvaHVT2BSK09wGeRlIAyxUN/OD4ZhDVJaRD2crpaAwZ5YgNv7wVJMTwU82Pn bqhESmUmolDB376+8gbPP3Irj1HpSq9bnzqaXjyLziwGboE5sGzzUqHNKbX1dKO29c hxRWbY/28dMrsVUt91JlWanaQx0rt/779c1ByLzUWBJGeGDKmXgpVm9b5HKtsa2KoA riSZilBHxPwpYcSenitshPZl36PBt1dSJoK78KzLsgJJiAaNFT1b6HhXSdsNh3sCDl yjiiOqqPEgPCw== Date: Tue, 27 Jul 2021 05:58:28 +0300 From: Jarkko Sakkinen To: Borys Movchan Cc: Peter Huewe , Jason Gunthorpe , kernel@axis.com, linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] tpm: Add Upgrade/Reduced mode support for TPM2 modules Message-ID: <20210727025828.giynspbcz7zdmosa@kernel.org> References: <20210719133717.18797-1-borysmn@axis.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210719133717.18797-1-borysmn@axis.com> Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org On Mon, Jul 19, 2021 at 03:37:17PM +0200, Borys Movchan wrote: > On some systems, especially embedded, TPM might start in > Upgrade/Reduced mode due to the previous failure of a firmware > upgrade process. Allow the TPM driver to handle such situations > properly. Enables a possibility for userspace application to > finalize TPM upgrade or recovery if required. Please add short explanation what you mean by upgrade/reduced mode. Maybe for clarity speak about upgrade mode. > > Signed-off-by: Borys Movchan > --- > drivers/char/tpm/tpm-chip.c | 23 +++++++++++++++-------- > drivers/char/tpm/tpm2-cmd.c | 12 ++++++++++-- > include/linux/tpm.h | 1 + > 3 files changed, 26 insertions(+), 10 deletions(-) > > diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c > index ddaeceb7e109..ff2367c447fb 100644 > --- a/drivers/char/tpm/tpm-chip.c > +++ b/drivers/char/tpm/tpm-chip.c > @@ -574,20 +574,25 @@ static int tpm_get_pcr_allocation(struct tpm_chip *chip) > int tpm_chip_register(struct tpm_chip *chip) > { > int rc; > + bool limited_mode = false; > > rc = tpm_chip_start(chip); > if (rc) > return rc; > rc = tpm_auto_startup(chip); > - if (rc) { > + if (rc == -EIO) { > + limited_mode = true; > + } else if (rc) { > tpm_chip_stop(chip); > return rc; > } > > - rc = tpm_get_pcr_allocation(chip); > - tpm_chip_stop(chip); > - if (rc) > - return rc; > + if (!limited_mode) { > + rc = tpm_get_pcr_allocation(chip); > + tpm_chip_stop(chip); > + if (rc) > + return rc; > + } > > tpm_sysfs_add_device(chip); > > @@ -595,9 +600,11 @@ int tpm_chip_register(struct tpm_chip *chip) > > tpm_add_ppi(chip); > > - rc = tpm_add_hwrng(chip); > - if (rc) > - goto out_ppi; > + if (!limited_mode) { > + rc = tpm_add_hwrng(chip); > + if (rc) > + goto out_ppi; > + } > > rc = tpm_add_char_device(chip); > if (rc) > diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c > index a25815a6f625..7468353ed67d 100644 > --- a/drivers/char/tpm/tpm2-cmd.c > +++ b/drivers/char/tpm/tpm2-cmd.c > @@ -718,7 +718,8 @@ static int tpm2_startup(struct tpm_chip *chip) > * sequence > * @chip: TPM chip to use > * > - * Returns 0 on success, < 0 in case of fatal error. > + * Returns 0 on success, -ENODEV in case of fatal error, > + * -EIO in case of Reduced/Upgrade mode > */ > int tpm2_auto_startup(struct tpm_chip *chip) > { > @@ -729,7 +730,10 @@ int tpm2_auto_startup(struct tpm_chip *chip) > goto out; > > rc = tpm2_do_selftest(chip); > - if (rc && rc != TPM2_RC_INITIALIZE) > + if (rc == TPM2_RC_UPGRADE) { > + rc = -EIO; > + goto out; > + } else if (rc && rc != TPM2_RC_INITIALIZE) > goto out; > > if (rc == TPM2_RC_INITIALIZE) { > @@ -743,6 +747,10 @@ int tpm2_auto_startup(struct tpm_chip *chip) > } > > rc = tpm2_get_cc_attrs_tbl(chip); > + if (rc) { /* Succeeded until here, but failed -> reduced mode */ > + rc = -EIO; > + goto out; > + } > > out: > if (rc > 0) > diff --git a/include/linux/tpm.h b/include/linux/tpm.h > index aa11fe323c56..e873c42907f0 100644 > --- a/include/linux/tpm.h > +++ b/include/linux/tpm.h > @@ -207,6 +207,7 @@ enum tpm2_return_codes { > TPM2_RC_INITIALIZE = 0x0100, /* RC_VER1 */ > TPM2_RC_FAILURE = 0x0101, > TPM2_RC_DISABLED = 0x0120, > + TPM2_RC_UPGRADE = 0x012D, > TPM2_RC_COMMAND_CODE = 0x0143, > TPM2_RC_TESTING = 0x090A, /* RC_WARN */ > TPM2_RC_REFERENCE_H0 = 0x0910, > -- > 2.20.1 > > /Jarkko