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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B95EBC433F5 for ; Tue, 16 Nov 2021 00:37:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9E7A861507 for ; Tue, 16 Nov 2021 00:37:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349335AbhKPAkf (ORCPT ); Mon, 15 Nov 2021 19:40:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:45204 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344951AbhKOTZs (ORCPT ); Mon, 15 Nov 2021 14:25:48 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id E0184633FA; Mon, 15 Nov 2021 19:07:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637003251; bh=bXaezZ6kRGfsjCKqfL5Q0OUnyboOsqDAJWO8aekBPwI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=r2kk1B+GtMUSxNv2D0cU00GLU2pl6gfmDUkhuw6oSK8NsRB9fp9eNO/kdxz6+YO5q i5x9IB6kV910ipCxneHSBxJP/0OtoKk2KzQ4ynaICQvQhJXkHvrYAjYW2vAOjY7e9A +Y2NshaGowx+31QSyhMzF8Aq5WfzK/Qvryb43owg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Shinichiro Kawasaki , Jan Kara , Jens Axboe Subject: [PATCH 5.15 866/917] block: Hold invalidate_lock in BLKDISCARD ioctl Date: Mon, 15 Nov 2021 18:06:01 +0100 Message-Id: <20211115165458.404242156@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165428.722074685@linuxfoundation.org> References: <20211115165428.722074685@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Shin'ichiro Kawasaki commit 7607c44c157d343223510c8ffdf7206fdd2a6213 upstream. When BLKDISCARD ioctl and data read race, the data read leaves stale page cache. To avoid the stale page cache, hold invalidate_lock of the block device file mapping. The stale page cache is observed when blktests test case block/009 is repeated hundreds of times. This patch can be applied back to the stable kernel version v5.15.y with slight patch edit. Rework is required for older stable kernels. Fixes: 351499a172c0 ("block: Invalidate cache on discard v2") Signed-off-by: Shin'ichiro Kawasaki Cc: stable@vger.kernel.org # v5.15 Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20211109104723.835533-2-shinichiro.kawasaki@wdc.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- block/ioctl.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) --- a/block/ioctl.c +++ b/block/ioctl.c @@ -113,6 +113,7 @@ static int blk_ioctl_discard(struct bloc uint64_t range[2]; uint64_t start, len; struct request_queue *q = bdev_get_queue(bdev); + struct inode *inode = bdev->bd_inode; int err; if (!(mode & FMODE_WRITE)) @@ -135,12 +136,17 @@ static int blk_ioctl_discard(struct bloc if (start + len > i_size_read(bdev->bd_inode)) return -EINVAL; + filemap_invalidate_lock(inode->i_mapping); err = truncate_bdev_range(bdev, mode, start, start + len - 1); if (err) - return err; + goto fail; - return blkdev_issue_discard(bdev, start >> 9, len >> 9, - GFP_KERNEL, flags); + err = blkdev_issue_discard(bdev, start >> 9, len >> 9, + GFP_KERNEL, flags); + +fail: + filemap_invalidate_unlock(inode->i_mapping); + return err; } static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode,