From patchwork Mon Jul 12 16:56:04 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 12371599 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,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 29B2DC11F6A for ; Mon, 12 Jul 2021 16:58:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 17127611CD for ; Mon, 12 Jul 2021 16:58:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234818AbhGLRAu (ORCPT ); Mon, 12 Jul 2021 13:00:50 -0400 Received: from smtp-out2.suse.de ([195.135.220.29]:54494 "EHLO smtp-out2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234797AbhGLQ7D (ORCPT ); Mon, 12 Jul 2021 12:59:03 -0400 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id 477E51FFD8; Mon, 12 Jul 2021 16:56:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1626108970; 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=iTYcqzKzVW0oBJ2ZSeBcw/3PSPPBIqymjzPuCMxKiy4ll/cAyuHykJMMhDGWNBhKCo9N6d JoKyDS1Vf/98lmBfMmGXVFVyohSVi0TCOIKxSEx2HfKnzIB6DVdHCaNV5uQEvNnGJJDYe5 BXJCgmkJRcXuloEW//0bAGfTMDLnT84= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1626108970; 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=TnUFj81r13w/wYsLizGkWgSqGm0ypAYnVLlQkqfeg3A6rxOUXmyJxudAqkSb53M7c4aI3M nbJlAd4Nq/JTdXCQ== Received: from quack2.suse.cz (unknown [10.100.224.230]) by relay2.suse.de (Postfix) with ESMTP id 31F9AA3B8B; Mon, 12 Jul 2021 16:56:10 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id E69101F2CE4; Mon, 12 Jul 2021 18:56:09 +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: Mon, 12 Jul 2021 18:56:04 +0200 Message-Id: <20210712165609.13215-13-jack@suse.cz> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210712163901.29514-1-jack@suse.cz> References: <20210712163901.29514-1-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/ZEDZAcsmYgBg7HQkAjeBC3GigbXzTaUkkhsP7h/tHN+6ua4RThYv n77PQ8aJATMEAAEIAB0WIQSrWdEr1p4yirVVKBycnaoHP2RA2QUCYOx0JAAKCRCcnaoHP2RA2dqDCA DMUmz3eKJXbKKMC35HDOwmLy0OWr2Q8JYrx2Zz9UI2uWVgU2WhLn/rATSlXPJNOvCBhNAHNerq4wgy 7PpwNJ+yrODpsPqO9TtPc9TkVC09gzyMEBd7zFvNwNo1HSBgCVqkhQDsIsoQ5qYKhnwXBcwUfe/jAG OrGz+CGinBfxWyd84sxZK5OI0xEsc+l1VRkwKNZvv3KZkwMMU2svJg7cL9j9hj9YAxiLuU5ZW8QGZ1 y6+a4hpeY6Y2uHEbvy2hQDJINGnW0A2SLcRYSknpM1/xzmH9sXxuLWPXAHMMnoILkmldGX6mMn95IT DMYouVz+KM3O+Gd6ROohEGhW/OH/mN 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: