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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2DB6BC77B73 for ; Mon, 22 May 2023 18:01:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230359AbjEVSBD (ORCPT ); Mon, 22 May 2023 14:01:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57874 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229767AbjEVSBC (ORCPT ); Mon, 22 May 2023 14:01:02 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 590E194 for ; Mon, 22 May 2023 11:01:01 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E05DB61F9E for ; Mon, 22 May 2023 18:01:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D4C25C433D2; Mon, 22 May 2023 18:00:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1684778460; bh=j9YTYv7FXhz8ptVE89y53trrD3G4EMuWqeo+4YG9zgc=; h=Subject:To:Cc:From:Date:From; b=C+4ALf0yTkLyLnRWU38X6xU7+iAKuoBEhMCzjoaEQDIHOFahNyP2uaFZhGvijoicU zQGLCAM3maFdipDVGX/zRwPujr9NMamfhvm6Jx3qbsxnf891XLwcWyXd9eNWi6cXXb +BaxWgfro0tlbtjwRmUPdLBNt/pO2suwExup+5YI= Subject: FAILED: patch "[PATCH] tpm: Prevent hwrng from activating during resume" failed to apply to 6.3-stable tree To: jarkko@kernel.org, jsnitsel@redhat.com Cc: From: Date: Mon, 22 May 2023 19:00:57 +0100 Message-ID: <2023052257-oppose-sculpture-982a@gregkh> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 6.3-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.3.y git checkout FETCH_HEAD git cherry-pick -x 99d46450625590d410f86fe4660a5eff7d3b8343 # git commit -s git send-email --to '' --in-reply-to '2023052257-oppose-sculpture-982a@gregkh' --subject-prefix 'PATCH 6.3.y' HEAD^.. Possible dependencies: 99d464506255 ("tpm: Prevent hwrng from activating during resume") 0c8862de05c1 ("tpm: Re-enable TPM chip boostrapping non-tpm_tis TPM drivers") 548eb516ec0f ("tpm, tpm_tis: startup chip before testing for interrupts") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 99d46450625590d410f86fe4660a5eff7d3b8343 Mon Sep 17 00:00:00 2001 From: Jarkko Sakkinen Date: Wed, 26 Apr 2023 20:29:28 +0300 Subject: [PATCH] tpm: Prevent hwrng from activating during resume Set TPM_CHIP_FLAG_SUSPENDED in tpm_pm_suspend() and reset in tpm_pm_resume(). While the flag is set, tpm_hwrng() gives back zero bytes. This prevents hwrng from racing during resume. Cc: stable@vger.kernel.org Fixes: 6e592a065d51 ("tpm: Move Linux RNG connection to hwrng") Reviewed-by: Jerry Snitselaar Signed-off-by: Jarkko Sakkinen diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index c10a4aa97373..cd48033b804a 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -571,6 +571,10 @@ static int tpm_hwrng_read(struct hwrng *rng, void *data, size_t max, bool wait) { struct tpm_chip *chip = container_of(rng, struct tpm_chip, hwrng); + /* Give back zero bytes, as TPM chip has not yet fully resumed: */ + if (chip->flags & TPM_CHIP_FLAG_SUSPENDED) + return 0; + return tpm_get_random(chip, data, max); } diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 4463d0018290..586ca10b0d72 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -412,6 +412,8 @@ int tpm_pm_suspend(struct device *dev) } suspended: + chip->flags |= TPM_CHIP_FLAG_SUSPENDED; + if (rc) dev_err(dev, "Ignoring error %d while suspending\n", rc); return 0; @@ -429,6 +431,14 @@ int tpm_pm_resume(struct device *dev) if (chip == NULL) return -ENODEV; + chip->flags &= ~TPM_CHIP_FLAG_SUSPENDED; + + /* + * Guarantee that SUSPENDED is written last, so that hwrng does not + * activate before the chip has been fully resumed. + */ + wmb(); + return 0; } EXPORT_SYMBOL_GPL(tpm_pm_resume); diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 77693389c3f9..6a1e8f157255 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -282,6 +282,7 @@ enum tpm_chip_flags { TPM_CHIP_FLAG_ALWAYS_POWERED = BIT(5), TPM_CHIP_FLAG_FIRMWARE_POWER_MANAGED = BIT(6), TPM_CHIP_FLAG_FIRMWARE_UPGRADE = BIT(7), + TPM_CHIP_FLAG_SUSPENDED = BIT(8), }; #define to_tpm_chip(d) container_of(d, struct tpm_chip, dev)