From patchwork Wed May 12 13:46:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 12253729 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=-16.8 required=3.0 tests=BAYES_00, 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 C0047C433ED for ; Wed, 12 May 2021 13:46:57 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3CCB060D07 for ; Wed, 12 May 2021 13:46:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3CCB060D07 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A12696B0074; Wed, 12 May 2021 09:46:38 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7A24F6B007D; Wed, 12 May 2021 09:46:38 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 35D086B007E; Wed, 12 May 2021 09:46:38 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0147.hostedemail.com [216.40.44.147]) by kanga.kvack.org (Postfix) with ESMTP id 179A36B007D for ; Wed, 12 May 2021 09:46:38 -0400 (EDT) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id B3CE39435 for ; Wed, 12 May 2021 13:46:37 +0000 (UTC) X-FDA: 78132704034.20.CC83874 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf22.hostedemail.com (Postfix) with ESMTP id 98AE9C000C45 for ; Wed, 12 May 2021 13:46:28 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id BD05EB1A6; Wed, 12 May 2021 13:46:32 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 0930B1F2B6C; Wed, 12 May 2021 15:46:32 +0200 (CEST) From: Jan Kara To: Cc: Christoph Hellwig , Dave Chinner , ceph-devel@vger.kernel.org, Chao Yu , Damien Le Moal , "Darrick J. Wong" , Jaegeuk Kim , Jeff Layton , Johannes Thumshirn , linux-cifs@vger.kernel.org, , linux-f2fs-devel@lists.sourceforge.net, , , Miklos Szeredi , Steve French , Ted Tso , Matthew Wilcox , Jan Kara Subject: [PATCH 10/11] ceph: Fix race between hole punch and page fault Date: Wed, 12 May 2021 15:46:18 +0200 Message-Id: <20210512134631.4053-10-jack@suse.cz> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210512101639.22278-1-jack@suse.cz> References: <20210512101639.22278-1-jack@suse.cz> MIME-Version: 1.0 Authentication-Results: imf22.hostedemail.com; dkim=none; dmarc=none; spf=pass (imf22.hostedemail.com: domain of jack@suse.cz designates 195.135.220.15 as permitted sender) smtp.mailfrom=jack@suse.cz X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 98AE9C000C45 X-Stat-Signature: md61y7f5cjf9mfseqwxicpob3eeth6ek Received-SPF: none (suse.cz>: No applicable sender policy available) receiver=imf22; identity=mailfrom; envelope-from=""; helo=mx2.suse.de; client-ip=195.135.220.15 X-HE-DKIM-Result: none/none X-HE-Tag: 1620827188-782225 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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 Signed-off-by: Jan Kara Reviewed-by: Jeff Layton --- 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 c1570fada3d8..6d868faf97b5 100644 --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -1401,9 +1401,11 @@ 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; + + down_read(&mapping->invalidate_lock); + page = find_or_create_page(mapping, 0, + mapping_gfp_constraint(mapping, ~__GFP_FS)); if (!page) { ret = VM_FAULT_OOM; goto out_inline; @@ -1424,6 +1426,7 @@ static vm_fault_t ceph_filemap_fault(struct vm_fault *vmf) vmf->page = page; ret = VM_FAULT_MAJOR | VM_FAULT_LOCKED; out_inline: + up_read(&mapping->invalidate_lock); 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 77fc037d5beb..91693d8b458e 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -2083,6 +2083,7 @@ static long ceph_fallocate(struct file *file, int mode, if (ret < 0) goto unlock; + down_write(&inode->i_mapping->invalidate_lock); ceph_zero_pagecache_range(inode, offset, length); ret = ceph_zero_objects(inode, offset, length); @@ -2095,6 +2096,7 @@ static long ceph_fallocate(struct file *file, int mode, if (dirty) __mark_inode_dirty(inode, dirty); } + up_write(&inode->i_mapping->invalidate_lock); ceph_put_cap_refs(ci, got); unlock: