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=-19.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 05533C07E99 for ; Fri, 9 Jul 2021 04:40:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DEF2D61448 for ; Fri, 9 Jul 2021 04:40:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229610AbhGIEne (ORCPT ); Fri, 9 Jul 2021 00:43:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40208 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229576AbhGIEnd (ORCPT ); Fri, 9 Jul 2021 00:43:33 -0400 Received: from mail-pj1-x1036.google.com (mail-pj1-x1036.google.com [IPv6:2607:f8b0:4864:20::1036]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2551AC061574 for ; Thu, 8 Jul 2021 21:40:51 -0700 (PDT) Received: by mail-pj1-x1036.google.com with SMTP id i16-20020a17090acf90b02901736d9d2218so378307pju.1 for ; Thu, 08 Jul 2021 21:40:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rubrik.com; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=56aVWSWfOHKsKJPA6NCmOjtMU3YQ6mTSJtwY537TrQI=; b=Kt09sRC4qc48Ie9+s4qct2Ddi84MxE3n9vkyub9b+63jkcPWL8c3KQPotPQuXgQ4/Q +M4aARGGgaLab8YjbWuQnHiRFvw6izJmMxjsNUl/Ku4K6L4cYFUm5XNlEjZXhQPs6hjS bZNswGaPTEhVZcsZnU9nztXGPQ/rrC5/gWYQE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=56aVWSWfOHKsKJPA6NCmOjtMU3YQ6mTSJtwY537TrQI=; b=PT/EV8RGSvn5E/qZAzZO7R6C0KXyEHxLnZZV/ndDacL/eB7sukzyCVFrXhNHr8ZKBb R2o1ypvFh0diHFW7gCKLhKPl97DFIxaorHUW+/Dchorea0N1X5U1N8z9B5b7Ja1Cb6oo gcHphjBgExkjcJ43ZowRL1jKWDGWob8E7iuKpYnyCm7XTUZjSmKALc/9xoDNFEbrOsTU y95si2iTXH5yaL8ihTMUC8Z6bjxIglnKUoHC/01y6bE+K07aRyI+uW3zFTziTkXcMhKH had3bH3euh3O0CQMuGSCxqn8OMc41YyTIB4mJK4oRoyrr4V1XvpL1Jbeib5DMSewNkCl YwdA== X-Gm-Message-State: AOAM530MOVJQO5M+rTp8OKhCkyGFw8CaFCsR6c8B+TrA2NOvf2I5m06z jxX5jyjBrb4RdEig84dpKBbX/A== X-Google-Smtp-Source: ABdhPJwlB7NRlH+yJPKUQimSHAjXEA8po0grcKYiMJusWq/VSocZQHERZh6+skZbhucY/JF8jpCdCw== X-Received: by 2002:a17:90a:d301:: with SMTP id p1mr8450833pju.45.1625805650530; Thu, 08 Jul 2021 21:40:50 -0700 (PDT) Received: from hao-wu-dev.colo.rubrik.com ([104.171.196.14]) by smtp.gmail.com with ESMTPSA id g141sm4410924pfb.210.2021.07.08.21.40.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 08 Jul 2021 21:40:50 -0700 (PDT) From: Hao Wu To: hao.wu@rubrik.com, shrihari.kalkar@rubrik.com, seungyeop.han@rubrik.com, anish.jhaveri@rubrik.com, peterhuewe@gmx.de, jarkko@kernel.org, jgg@ziepe.ca, linux-integrity@vger.kernel.org, pmenzel@molgen.mpg.de, kgold@linux.ibm.com, zohar@linux.vnet.ibm.com, why2jjj.linux@gmail.com, hamza@hpe.com, gregkh@linuxfoundation.org, arnd@arndb.de, nayna@linux.vnet.ibm.com, James.Bottomley@hansenpartnership.com Subject: [PATCH v2] tpm: fix Atmel TPM crash caused by too frequent queries Date: Thu, 8 Jul 2021 21:40:28 -0700 Message-Id: <20210709044028.77278-1-hao.wu@rubrik.com> X-Mailer: git-send-email 2.29.0.vfs.0.0 In-Reply-To: <20210630042205.30051-1-hao.wu@rubrik.com> References: <20210630042205.30051-1-hao.wu@rubrik.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org The Atmel TPM 1.2 chips crash with error `tpm_try_transmit: send(): error -62` since kernel 4.14. It is observed from the kernel log after running `tpm_sealdata -z`. The error thrown from the command is as follows ``` $ tpm_sealdata -z Tspi_Key_LoadKey failed: 0x00001087 - layer=tddl, code=0087 (135), I/O error ``` The issue was reproduced with the following Atmel TPM chip: ``` $ tpm_version T0 TPM 1.2 Version Info: Chip Version: 1.2.66.1 Spec Level: 2 Errata Revision: 3 TPM Vendor ID: ATML TPM Version: 01010000 Manufacturer Info: 41544d4c ``` The root cause of the issue is due to the TPM calls to msleep() were replaced with usleep_range() [1], which reduces the actual timeout. Via experiments, it is observed that the original msleep(5) actually sleeps for 15ms. Because of a known timeout issue in Atmel TPM 1.2 chip, the shorter timeout than 15ms can cause the error described above. A few further changes in kernel 4.16 [2] and 4.18 [3, 4] further reduced the timeout to less than 1ms. With experiments, the problematic timeout in the latest kernel is the one for `wait_for_tpm_stat`. To fix it, the patch reverts the timeout of `wait_for_tpm_stat` to 15ms for all Atmel TPM 1.2 chips, but leave it untouched for Ateml TPM 2.0 chip, and chips from other vendors. As explained above, the chosen 15ms timeout is the actual timeout before this issue introduced, thus the old value is used here. Particularly, TPM_ATML_TIMEOUT_WAIT_STAT_MIN is set to 14700us, TPM_ATML_TIMEOUT_WAIT_STAT_MIN is set to 15000us according to the existing TPM_TIMEOUT_RANGE_US (300us). The fixed has been tested in the system with the affected Atmel chip with no issues observed after boot up. References: [1] 9f3fc7bcddcb tpm: replace msleep() with usleep_range() in TPM 1.2/2.0 generic drivers [2] cf151a9a44d5 tpm: reduce tpm polling delay in tpm_tis_core [3] 59f5a6b07f64 tpm: reduce poll sleep time in tpm_transmit() [4] 424eaf910c32 tpm: reduce polling time to usecs for even finer granularity Fixes: 9f3fc7bcddcb ("tpm: replace msleep() with usleep_range() in TPM 1.2/2.0 generic drivers") Link: https://patchwork.kernel.org/project/linux-integrity/patch/20200926223150.109645-1-hao.wu@rubrik.com/ Signed-off-by: Hao Wu --- This version (v2) has following changes on top of the last (v1): - follow the existing way to define two timeouts (min and max) for ATMEL chip, thus keep the exact timeout logic for non-ATEML chips. - limit the timeout increase to only ATMEL TPM 1.2 chips, because it is not an issue for TPM 2.0 chips yet. Test Plan: - Run fixed kernel with ATMEL TPM chips and see crash has been fixed. - Run fixed kernel with non-ATMEL TPM chips, and confirm the timeout has not been changed. drivers/char/tpm/tpm.h | 6 ++++-- drivers/char/tpm/tpm_tis_core.c | 23 +++++++++++++++++++++-- include/linux/tpm.h | 3 +++ 3 files changed, 28 insertions(+), 4 deletions(-) diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 283f78211c3a..6de1b44c4aab 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -41,8 +41,10 @@ enum tpm_timeout { TPM_TIMEOUT_RETRY = 100, /* msecs */ TPM_TIMEOUT_RANGE_US = 300, /* usecs */ TPM_TIMEOUT_POLL = 1, /* msecs */ - TPM_TIMEOUT_USECS_MIN = 100, /* usecs */ - TPM_TIMEOUT_USECS_MAX = 500 /* usecs */ + TPM_TIMEOUT_USECS_MIN = 100, /* usecs */ + TPM_TIMEOUT_USECS_MAX = 500, /* usecs */ + TPM_ATML_TIMEOUT_WAIT_STAT_MIN = 14700, /* usecs */ + TPM_ATML_TIMEOUT_WAIT_STAT_MAX = 15000 /* usecs */ }; /* TPM addresses */ diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index 55b9d3965ae1..ae27d66fdd94 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -80,8 +80,17 @@ static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, } } else { do { - usleep_range(TPM_TIMEOUT_USECS_MIN, - TPM_TIMEOUT_USECS_MAX); + /* this code path could be executed before + * timeouts initialized in chip instance. + */ + if (chip->timeout_wait_stat_min && + chip->timeout_wait_stat_max) + usleep_range(chip->timeout_wait_stat_min, + chip->timeout_wait_stat_max); + else + usleep_range(TPM_TIMEOUT_USECS_MIN, + TPM_TIMEOUT_USECS_MAX); + status = chip->ops->status(chip); if ((status & mask) == mask) return 0; @@ -934,6 +943,9 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, chip->timeout_b = msecs_to_jiffies(TIS_TIMEOUT_B_MAX); chip->timeout_c = msecs_to_jiffies(TIS_TIMEOUT_C_MAX); chip->timeout_d = msecs_to_jiffies(TIS_TIMEOUT_D_MAX); + /* init timeouts for wait_for_tpm_stat */ + chip->timeout_wait_stat_min = TPM_TIMEOUT_USECS_MIN; + chip->timeout_wait_stat_max = TPM_TIMEOUT_USECS_MAX; priv->phy_ops = phy_ops; dev_set_drvdata(&chip->dev, priv); @@ -983,6 +995,13 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, priv->manufacturer_id = vendor; + if (priv->manufacturer_id == TPM_VID_ATML && + !(chip->flags & TPM_CHIP_FLAG_TPM2)) { + /* If TPM chip is 1.2 ATMEL chip, timeout need to be relaxed*/ + chip->timeout_wait_stat_min = TPM_ATML_TIMEOUT_WAIT_STAT_MIN; + chip->timeout_wait_stat_max = TPM_ATML_TIMEOUT_WAIT_STAT_MAX; + } + rc = tpm_tis_read8(priv, TPM_RID(0), &rid); if (rc < 0) goto out_err; diff --git a/include/linux/tpm.h b/include/linux/tpm.h index aa11fe323c56..171b9102c976 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -150,6 +150,8 @@ struct tpm_chip { bool timeout_adjusted; unsigned long duration[TPM_NUM_DURATIONS]; /* jiffies */ bool duration_adjusted; + unsigned int timeout_wait_stat_min; /* usecs */ + unsigned int timeout_wait_stat_max; /* usecs */ struct dentry *bios_dir[TPM_NUM_EVENT_LOG_FILES]; @@ -269,6 +271,7 @@ enum tpm2_cc_attrs { #define TPM_VID_INTEL 0x8086 #define TPM_VID_WINBOND 0x1050 #define TPM_VID_STM 0x104A +#define TPM_VID_ATML 0x1114 enum tpm_chip_flags { TPM_CHIP_FLAG_TPM2 = BIT(1), -- 2.29.0.vfs.0.0