From patchwork Thu Jun 2 18:18:10 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 12868050 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 CC904C433EF for ; Thu, 2 Jun 2022 18:18:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237980AbiFBSSh (ORCPT ); Thu, 2 Jun 2022 14:18:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43578 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237920AbiFBSSX (ORCPT ); Thu, 2 Jun 2022 14:18:23 -0400 Received: from ale.deltatee.com (ale.deltatee.com [204.191.154.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E95394D9CF; Thu, 2 Jun 2022 11:18:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltatee.com; s=20200525; h=Subject:MIME-Version:References:In-Reply-To: Message-Id:Date:Cc:To:From:content-disposition; bh=3NgWxjjGjfH7QAQ8Wc4h1yGFk2yNyL7ffDtojTNOAXU=; b=oQuiLH+o6kVXVs6A4NxLoL+hff xflJWX4GpVLBxKPXa2Zh1+xUlxN3OvJKYMDB1SB5wXXnCTgIHxotY2m9m8wVcAPd0nGWcoxaF2wrD LVmm+rHmIhoL7TTgfuLeWhbaKIObvHxFr0ZhHzIaTYaqoCERCAzV0vdbAbH7wVFXtDGoykASfof3Z /9IPGWSX3AboqPnJ4sdwXDiI9Btt7KWT4NzTEJjY6BisxVzyHMvEK0wtEZx/kERIRlehlk0z2n2k7 dU7TRYVc14QhG0AM1lkjAm7Z48VosWKcLJlWe0TabyWtanN7xP1o+EJV4iZVsQn57Tdp3xkrk01NS noR3iFbg==; Received: from cgy1-donard.priv.deltatee.com ([172.16.1.31]) by ale.deltatee.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nwpOm-00EPmZ-Pu; Thu, 02 Jun 2022 12:18:22 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.94.2) (envelope-from ) id 1nwpOm-000DDM-0j; Thu, 02 Jun 2022 12:18:20 -0600 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, Song Liu Cc: Christoph Hellwig , Donald Buczek , Guoqing Jiang , Xiao Ni , Stephen Bates , Martin Oliveira , David Sloan , Logan Gunthorpe Date: Thu, 2 Jun 2022 12:18:10 -0600 Message-Id: <20220602181818.50729-5-logang@deltatee.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220602181818.50729-1-logang@deltatee.com> References: <20220602181818.50729-1-logang@deltatee.com> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, song@kernel.org, hch@infradead.org, buczek@molgen.mpg.de, guoqing.jiang@linux.dev, xni@redhat.com, sbates@raithlin.com, Martin.Oliveira@eideticom.com, David.Sloan@eideticom.com, logang@deltatee.com X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [PATCH v3 04/11] md/raid5-cache: Take mddev_lock in r5c_journal_mode_show() X-SA-Exim-Version: 4.2.1 (built Sat, 13 Feb 2021 17:57:42 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org The mddev->lock spinlock doesn't protect against the removal of conf->log in r5l_exit_log() so conf->log may be freed before it is used. To fix this, take the mddev_lock() insteaad of the mddev->lock spinlock. Signed-off-by: Logan Gunthorpe Reviewed-by: Christoph Hellwig --- drivers/md/raid5-cache.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c index 83c184eddbda..69b95005abca 100644 --- a/drivers/md/raid5-cache.c +++ b/drivers/md/raid5-cache.c @@ -2534,10 +2534,13 @@ static ssize_t r5c_journal_mode_show(struct mddev *mddev, char *page) struct r5conf *conf; int ret; - spin_lock(&mddev->lock); + ret = mddev_lock(mddev); + if (ret) + return ret; + conf = mddev->private; if (!conf || !conf->log) { - spin_unlock(&mddev->lock); + mddev_unlock(mddev); return 0; } @@ -2557,7 +2560,7 @@ static ssize_t r5c_journal_mode_show(struct mddev *mddev, char *page) default: ret = 0; } - spin_unlock(&mddev->lock); + mddev_unlock(mddev); return ret; } @@ -3167,6 +3170,8 @@ void r5l_exit_log(struct r5conf *conf) { struct r5l_log *log = conf->log; + lockdep_assert_held(&conf->mddev->reconfig_mutex); + conf->log = NULL; synchronize_rcu();