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,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 07B75C4BA3C for ; Mon, 7 Jun 2021 14:52:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E226D60FE5 for ; Mon, 7 Jun 2021 14:52:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231415AbhFGOyk (ORCPT ); Mon, 7 Jun 2021 10:54:40 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:34746 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230478AbhFGOyb (ORCPT ); Mon, 7 Jun 2021 10:54:31 -0400 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id 0464C21A9F; Mon, 7 Jun 2021 14:52:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1623077558; 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=vl6h8io6lSoWK7OIrnD7E7ya5J3bdZJ7HzP2D9qWuTI=; b=pKfvrYrcy1xAVtKNmw9VHwTemgYio9dqCCXj2qp2s2JWUKyLBGbU0ymRIUsFMTnem07EFP Rdc/QIuzF2BthdMO2sBS/L4z/rA/917Pf9sTft9oGj3xqIWDaTmw14BY3oBHj9U9ZUA7P4 3CsHFNGPY7rieEn/jaNNM+eG7j7qPGM= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1623077558; 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=vl6h8io6lSoWK7OIrnD7E7ya5J3bdZJ7HzP2D9qWuTI=; b=3pUZCLZilKHDEtXnzJoG6nngWw0wNgbZHlnJxu0cudCyLBIYO1DwS4rc3i5Vx4QUQ3xDzz VUH9U7p0kK3UXkCw== Received: from quack2.suse.cz (unknown [10.100.200.198]) by relay2.suse.de (Postfix) with ESMTP id DA79EA3B99; Mon, 7 Jun 2021 14:52:37 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id C41211F2CC0; Mon, 7 Jun 2021 16:52:36 +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 14/14] cifs: Fix race between hole punch and page fault Date: Mon, 7 Jun 2021 16:52:24 +0200 Message-Id: <20210607145236.31852-14-jack@suse.cz> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210607144631.8717-1-jack@suse.cz> References: <20210607144631.8717-1-jack@suse.cz> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1533; h=from:subject; bh=yLMJejfXbe3cEmy2dQFvIvX02RxXlz2mOO0L4SMl8Co=; b=owEBbQGS/pANAwAIAZydqgc/ZEDZAcsmYgBgvjKnJxY3aOf0Uh04RpHAOh/EZgichtc+O2fd+Y+C czFMeL2JATMEAAEIAB0WIQSrWdEr1p4yirVVKBycnaoHP2RA2QUCYL4ypwAKCRCcnaoHP2RA2Ue3B/ 9exfyIQAzlGqcG2osnZCouldM63nI3uW0xQ2C9f5oG2IPFvR9kW48iWOZvY8IeVLn/hDfPcumyTE3S rVE5Wb8HloLQVQrPKhUTw8U7QuIJVnxEWeBrOQRkcJm2p/i8DGH/tJK6Iw/z6QFn3oEoOyOT96u/HQ XvMcq+lNmKNSfUE9n6xOQJOdvYt2bMCS7UF3V1ONE8X1HkyUHJxDYBL+zW7gTkfxuBg+Ym0QIiNQzi zBwKLs2btjQxoUfPsSpa6AqqbGrmx+OjASJLWob322k8teI7Y8mEDXc6smlXTSonPzIEcQRXKvJoIG PzUylz0kA5utwu4PimVcuV48+9RTJg X-Developer-Key: i=jack@suse.cz; a=openpgp; fpr=93C6099A142276A28BBE35D815BC833443038D8C Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: ceph-devel@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 dd0eb665b680..e41ea254beaa 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -3579,6 +3579,7 @@ 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. @@ -3596,6 +3597,7 @@ 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