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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 4418DC433C1 for ; Mon, 22 Mar 2021 07:18:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 09ED461879 for ; Mon, 22 Mar 2021 07:18:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229614AbhCVHS2 (ORCPT ); Mon, 22 Mar 2021 03:18:28 -0400 Received: from verein.lst.de ([213.95.11.211]:53831 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229696AbhCVHSE (ORCPT ); Mon, 22 Mar 2021 03:18:04 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id 0C2A368BEB; Mon, 22 Mar 2021 08:18:02 +0100 (CET) Date: Mon, 22 Mar 2021 08:18:01 +0100 From: Christoph Hellwig To: syzbot Cc: axboe@kernel.dk, hch@lst.de, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, tj@kernel.org Subject: Re: [syzbot] KASAN: use-after-free Read in disk_part_iter_next (2) Message-ID: <20210322071801.GE3440@lst.de> References: <00000000000053da9405bd7d2644@google.com> <000000000000a17fb305be0b3f38@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <000000000000a17fb305be0b3f38@google.com> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org I've been running the reproducer on a KASAN enable VM for about 15 minutes now, but haven't been able to reproduce it. Is there a way to inject this proposed fix into the syzbot queue? diff --git a/block/partitions/core.c b/block/partitions/core.c index 1a7558917c47d6..f5d5872b89d57e 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -288,15 +288,12 @@ struct device_type part_type = { void delete_partition(struct block_device *part) { xa_erase(&part->bd_disk->part_tbl, part->bd_partno); - kobject_put(part->bd_holder_dir); - device_del(&part->bd_device); - - /* - * Remove the block device from the inode hash, so that it cannot be - * looked up any more even when openers still hold references. - */ remove_inode_hash(part->bd_inode); + synchronize_rcu(); + + kobject_put(part->bd_holder_dir); + device_del(&part->bd_device); put_device(&part->bd_device); }