From patchwork Thu Jul 15 13:40:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 12380085 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=-18.8 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 A2A8FC4BA3C for ; Thu, 15 Jul 2021 13:40:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 919B461167 for ; Thu, 15 Jul 2021 13:40:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238101AbhGONnu (ORCPT ); Thu, 15 Jul 2021 09:43:50 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:55812 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237754AbhGONnf (ORCPT ); Thu, 15 Jul 2021 09:43:35 -0400 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id 861F422A7F; Thu, 15 Jul 2021 13:40:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1626356433; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=blXH/6I2F2wS3AR3z8Jn+sP5qB3/RsNTR1FPrDAVGAo=; b=wKNzZoaLDjhipnh8ttsBgje5D0Ok3rqr4tTSatFCIsiR8C0wwioWb9OQ7GyVYuO3zx7s/o x66RWB/W4cf+VKAQtsyhs1yitLudsWYgZeLsq3s1PjdlcmTX/TmHeiL7rk7tTdnBvLbdG3 glpPwHOWpQ5LyLWndaVoXIq96AxjLgM= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1626356433; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=blXH/6I2F2wS3AR3z8Jn+sP5qB3/RsNTR1FPrDAVGAo=; b=3IDWz7NTfWFD9C5Lyl1NHQ8/UihGE3JVo7rfCzqxP17la0uNiEHKtrXZPHB3iHx+qY8G4o pjuUCLnJZ/JHKEBw== Received: from quack2.suse.cz (unknown [10.100.200.198]) by relay2.suse.de (Postfix) with ESMTP id 73768A3BA6; Thu, 15 Jul 2021 13:40:33 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 31F8B1E10FD; Thu, 15 Jul 2021 15:40:33 +0200 (CEST) From: Jan Kara To: Cc: , Christoph Hellwig , "Darrick J. Wong" , Ted Tso , Dave Chinner , Matthew Wilcox , , , linux-f2fs-devel@lists.sourceforge.net, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, Jan Kara , Jeff Layton Subject: [PATCH 13/14] ceph: Fix race between hole punch and page fault Date: Thu, 15 Jul 2021 15:40:23 +0200 Message-Id: <20210715134032.24868-13-jack@suse.cz> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210715133202.5975-1-jack@suse.cz> References: <20210715133202.5975-1-jack@suse.cz> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2465; h=from:subject; bh=YtbsQ0zyJQcvofUJ0OfZKBGWEvBnT2OBf1X3WQMmS78=; b=owEBbQGS/pANAwAIAZydqgc/ZEDZAcsmYgBg8DrGAjeBC3GigbXzTaUkkhsP7h/tHN+6ua4RThYv n77PQ8aJATMEAAEIAB0WIQSrWdEr1p4yirVVKBycnaoHP2RA2QUCYPA6xgAKCRCcnaoHP2RA2Uk5B/ wIPJb+pvH9ICTCScS6xTQ9YeFoVZSSLdhM5PjEAGgZTtYWqHre6ndf2vXYsaKDMJy69rgTLxtrpQpa /AJgkGaTIuip7mdIFkbLA1UvsUdX+crmGVYg6QE04F6VKiTuy5EqSb1h0Y9YsDBVxwjHuqb4bECYq4 VbxzLGyeS1KMWDBuJizggPabh3yL9EC1NyWmQ/da2wqqlCtgOlTUxIcmsg1po0j7nJUAgn0dJcA3d4 tbTVc7ltQH+OvEN4CrDutgB4RtaiyttV4pmFYF7AL/F6U9L0vSlNC0yXHNFjKanGlbKvK/3sD6Lw6S JoKKNO5Us08YCrHUyo8hNTs/Q3SX3W X-Developer-Key: i=jack@suse.cz; a=openpgp; fpr=93C6099A142276A28BBE35D815BC833443038D8C Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org Ceph has a following race between hole punching and page fault: CPU1 CPU2 ceph_fallocate() ... ceph_zero_pagecache_range() ceph_filemap_fault() faults in page in the range being punched ceph_zero_objects() And now we have a page in punched range with invalid data. Fix the problem by using mapping->invalidate_lock similarly to other filesystems. Note that using invalidate_lock also fixes a similar race wrt ->readpage(). CC: Jeff Layton CC: ceph-devel@vger.kernel.org Reviewed-by: Jeff Layton Signed-off-by: Jan Kara --- fs/ceph/addr.c | 9 ++++++--- fs/ceph/file.c | 2 ++ 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c index a1e2813731d1..7e7a897ae0d3 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -1395,9 +1395,11 @@ static vm_fault_t ceph_filemap_fault(struct vm_fault *vmf) ret = VM_FAULT_SIGBUS; } else { struct address_space *mapping = inode->i_mapping; - struct page *page = find_or_create_page(mapping, 0, - mapping_gfp_constraint(mapping, - ~__GFP_FS)); + struct page *page; + + filemap_invalidate_lock_shared(mapping); + page = find_or_create_page(mapping, 0, + mapping_gfp_constraint(mapping, ~__GFP_FS)); if (!page) { ret = VM_FAULT_OOM; goto out_inline; @@ -1418,6 +1420,7 @@ static vm_fault_t ceph_filemap_fault(struct vm_fault *vmf) vmf->page = page; ret = VM_FAULT_MAJOR | VM_FAULT_LOCKED; out_inline: + filemap_invalidate_unlock_shared(mapping); dout("filemap_fault %p %llu read inline data ret %x\n", inode, off, ret); } diff --git a/fs/ceph/file.c b/fs/ceph/file.c index d1755ac1d964..e1d605a02d4a 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -2088,6 +2088,7 @@ static long ceph_fallocate(struct file *file, int mode, if (ret < 0) goto unlock; + filemap_invalidate_lock(inode->i_mapping); ceph_zero_pagecache_range(inode, offset, length); ret = ceph_zero_objects(inode, offset, length); @@ -2100,6 +2101,7 @@ static long ceph_fallocate(struct file *file, int mode, if (dirty) __mark_inode_dirty(inode, dirty); } + filemap_invalidate_unlock(inode->i_mapping); ceph_put_cap_refs(ci, got); unlock: