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 5828BC433EF for ; Wed, 20 Oct 2021 01:56:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3A7386113D for ; Wed, 20 Oct 2021 01:56:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229691AbhJTB6s (ORCPT ); Tue, 19 Oct 2021 21:58:48 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:34337 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230015AbhJTB6r (ORCPT ); Tue, 19 Oct 2021 21:58:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634694994; h=from:from:reply-to:subject:subject: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=freyuG48ucRP6h2e8+iworwUl5TwR3fT12ETkCRsZlI=; b=TfVcDKlxDKmE16T41e8skku+95eGh/5KN6g42WCKvprmrkcb5OXh53Hu3kpEw/ik6QJWOX LCubrXta2DTdI9O60W+VeaoyUW7vslN3kG1l2vB79TZy1Q9QQQNJVPgWjh/kVz8YdpThDr bfyHoqIpLlepxWKNq7eQ5X3P/skWyX0= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-187-mcfFYADuMQicWSea3cNWvg-1; Tue, 19 Oct 2021 21:56:30 -0400 X-MC-Unique: mcfFYADuMQicWSea3cNWvg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 73E31362FD; Wed, 20 Oct 2021 01:56:29 +0000 (UTC) Received: from localhost (ovpn-8-20.pek2.redhat.com [10.72.8.20]) by smtp.corp.redhat.com (Postfix) with ESMTP id B5FEA6A8F5; Wed, 20 Oct 2021 01:56:22 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Luis Chamberlain , Minchan Kim , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Ming Lei Subject: [PATCH V2 3/4] zram: avoid race between zram_remove and disksize_store Date: Wed, 20 Oct 2021 09:55:47 +0800 Message-Id: <20211020015548.2374568-4-ming.lei@redhat.com> In-Reply-To: <20211020015548.2374568-1-ming.lei@redhat.com> References: <20211020015548.2374568-1-ming.lei@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org After resetting device in zram_remove(), disksize_store still may come and allocate resources again before deleting gendisk, fix the race by resetting zram after del_gendisk() returns. At that time, disksize_store can't come any more. Reported-by: Luis Chamberlain Signed-off-by: Ming Lei --- drivers/block/zram/zram_drv.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 8883de7aa3d7..6078d1dae44a 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -2002,6 +2002,13 @@ static int zram_remove(struct zram *zram) /* del_gendisk drains pending reset_store */ WARN_ON_ONCE(claimed && zram->claim); + /* + * disksize store may come between zram_reset_device and del_gendisk, so + * run the last reset for avoiding leak anything allocated in + * disksize_store(). + */ + zram_reset_device(zram); + blk_cleanup_disk(zram->disk); kfree(zram); return 0; -- 2.31.1