From patchwork Wed Sep 13 11:10:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 13382847 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 7743FEDEC43 for ; Wed, 13 Sep 2023 11:11:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240079AbjIMLLN (ORCPT ); Wed, 13 Sep 2023 07:11:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57572 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239924AbjIMLLJ (ORCPT ); Wed, 13 Sep 2023 07:11:09 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8F5491BC3; Wed, 13 Sep 2023 04:10:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=Xklao4KHcROHR/8WDTUTeOE5QrsYvb1TOynYxxAM1IY=; b=0av/5m717cplc+QOcwl88ZZhkv YQM9yzvQDx1wwNM1F4FN/+TZdcZakCPUB9tpX7qIKXviEYJGNiKL7nM6wzdoFpXYUwE8dRlxYP85n AheRdG3C68ZFMu0glT+SSrQiXRTWdZz1OA6HzM3aCxLykdLie2/UAUNYXAUOU8LULnl7dF85H1y3I bfHoOdc64/KYRLDOL+/ElcKMIOyRVN8LF7dTQpsazJCGbzefGXOUpSfMlN8KQMxT5w6XrbKzELime Ut1U2f7WzU7RHmh/n7g+ZCkfXpAq547wD8l7r+0tUECJw5acUGSocQEMGdzdnjGO/bAAnIc7s4T9b hrVh7h5Q==; Received: from [190.210.221.22] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.96 #2 (Red Hat Linux)) id 1qgNli-005hzf-03; Wed, 13 Sep 2023 11:10:50 +0000 From: Christoph Hellwig To: Christian Brauner , Al Viro Cc: Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Fenghua Yu , Reinette Chatre , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Dennis Dalessandro , Tejun Heo , Trond Myklebust , Anna Schumaker , Kees Cook , Damien Le Moal , Naohiro Aota , Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org, linux-hardening@vger.kernel.org, cgroups@vger.kernel.org Subject: [PATCH 08/19] pstore: shrink the pstore_sb_lock critical section in pstore_kill_sb Date: Wed, 13 Sep 2023 08:10:02 -0300 Message-Id: <20230913111013.77623-9-hch@lst.de> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230913111013.77623-1-hch@lst.de> References: <20230913111013.77623-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org ->kill_sb can't race with creating ->fill_super because pstore is a _single file system that only ever has a single sb instance, and we wait for the previous one to go away before creating a new one. Reduce the critical section so that is is not held over generic_shutdown_super. Signed-off-by: Christoph Hellwig Reviewed-by: Kees Cook --- fs/pstore/inode.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c index 585360706b335f..fd1d24b47160d0 100644 --- a/fs/pstore/inode.c +++ b/fs/pstore/inode.c @@ -467,10 +467,9 @@ static struct dentry *pstore_mount(struct file_system_type *fs_type, static void pstore_kill_sb(struct super_block *sb) { - mutex_lock(&pstore_sb_lock); - WARN_ON(pstore_sb && pstore_sb != sb); - kill_litter_super(sb); + + mutex_lock(&pstore_sb_lock); pstore_sb = NULL; mutex_lock(&records_list_lock);