From mboxrd@z Thu Jan 1 00:00:00 1970 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=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 4C5B3C11F6D 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 2BC8C61222 for ; Mon, 12 Jul 2021 16:58:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235063AbhGLRAv (ORCPT ); Mon, 12 Jul 2021 13:00:51 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:34630 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234778AbhGLQ7D (ORCPT ); Mon, 12 Jul 2021 12:59:03 -0400 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id 4BC5F2212F; 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=aHhQqe8KTjBCv9r4mi6xe2At5YRjoevCFxA6zjCOvEc=; b=ZESWo0+jV0zYOW8UBnDvLHP40wD4Mizkdi3GL2a5tQw4l+5H/3r+WCw8lG38ognWMuzAir tcOcmkCMPX37xr1NU0VCTckY3UvvDDj7tTD3Bu1lsU8C3dGjMa8KO/+dkjOoL7uaQvat0m liWED2/F46K5fur5cg9oAjmpvcw++80= 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=aHhQqe8KTjBCv9r4mi6xe2At5YRjoevCFxA6zjCOvEc=; b=nwaFUtZvJiGfTCuyP2yCuDyUqORKcbdPqKWTp4GjFiBFK+dHUOfXJaNP2sLvWW4bNywxzi Vs5yDOLGBuV5+AAg== Received: from quack2.suse.cz (unknown [10.100.224.230]) by relay2.suse.de (Postfix) with ESMTP id 34EB6A3B8C; Mon, 12 Jul 2021 16:56:10 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id EADE31F2CE6; 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 , Steve French Subject: [PATCH 14/14] cifs: Fix race between hole punch and page fault Date: Mon, 12 Jul 2021 18:56:05 +0200 Message-Id: <20210712165609.13215-14-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=1533; h=from:subject; bh=1e9BARQoajJDSgUdYORenFPF3ecMZ7Jduf79ehs8h7w=; b=owEBbQGS/pANAwAIAZydqgc/ZEDZAcsmYgBg7HQkAS6+mJ6okwtt/iRndokM6RsjeRiTUsodrmWd daZifx6JATMEAAEIAB0WIQSrWdEr1p4yirVVKBycnaoHP2RA2QUCYOx0JAAKCRCcnaoHP2RA2a2dB/ sGPl7L7iNC+Ygp3aaAb8TuC+CK7Fa16RT+41tzwVRlQcnfmi7CVZIqfg9wn8dFg+Rwo985dKOjqKBC Rkbj05bjkHH9zmlZ5YZ+X92bgSHksva5hcdPkI3PM5v6sCXvIMGdeKJvQ7OUyLqoS8vAwHFZCA6FfN oKBhzEjKFekquNo/8GdftAgbDSO70kSs2v1iR2SpAHq/DWr1NsJ0/SUel0YbkYCJVK/t1Jybo0fOS3 hzlpdrYgSafKZV1HZ762tDktI+gjO6r/m5sW8bVZitIHHqVxrctKOIPAGfL2NMRnxMzWVNlMBMdoo7 Y6A0YzNG5g9ezVbk8Vutbf63fL3esc X-Developer-Key: i=jack@suse.cz; a=openpgp; fpr=93C6099A142276A28BBE35D815BC833443038D8C Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org Cifs has a following race between hole punching and page fault: CPU1 CPU2 smb3_fallocate() smb3_punch_hole() truncate_pagecache_range() filemap_fault() - loads old data into the page cache SMB2_ioctl(..., FSCTL_SET_ZERO_DATA, ...) And now we have stale data in the page cache. Fix the problem by locking out faults (as well as reads) using mapping->invalidate_lock while hole punch is running. CC: Steve French CC: linux-cifs@vger.kernel.org Signed-off-by: Jan Kara --- fs/cifs/smb2ops.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index e4c8f603dd58..458c546ce8cd 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -3588,6 +3588,7 @@ static long smb3_punch_hole(struct file *file, struct cifs_tcon *tcon, return rc; } + filemap_invalidate_lock(inode->i_mapping); /* * We implement the punch hole through ioctl, so we need remove the page * caches first, otherwise the data may be inconsistent with the server. @@ -3605,6 +3606,7 @@ static long smb3_punch_hole(struct file *file, struct cifs_tcon *tcon, sizeof(struct file_zero_data_information), CIFSMaxBufSize, NULL, NULL); free_xid(xid); + filemap_invalidate_unlock(inode->i_mapping); return rc; } -- 2.26.2