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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 82F4DC433E0 for ; Tue, 11 Aug 2020 06:51:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 68C8920774 for ; Tue, 11 Aug 2020 06:51:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728282AbgHKGvR (ORCPT ); Tue, 11 Aug 2020 02:51:17 -0400 Received: from mx2.suse.de ([195.135.220.15]:34292 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727971AbgHKGvQ (ORCPT ); Tue, 11 Aug 2020 02:51:16 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id E2729AD43; Tue, 11 Aug 2020 06:51:35 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id D9FD0DAFD3; Tue, 11 Aug 2020 08:50:13 +0200 (CEST) Date: Tue, 11 Aug 2020 08:50:13 +0200 From: David Sterba To: syzbot Cc: clm@fb.com, davem@davemloft.net, dsterba@suse.com, johan.hedberg@gmail.com, josef@toxicpanda.com, kuba@kernel.org, linux-bluetooth@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, marcel@holtmann.org, nborisov@suse.com, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: KASAN: use-after-free Write in hci_conn_del Message-ID: <20200811065013.GI2026@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, syzbot , clm@fb.com, davem@davemloft.net, dsterba@suse.com, johan.hedberg@gmail.com, josef@toxicpanda.com, kuba@kernel.org, linux-bluetooth@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, marcel@holtmann.org, nborisov@suse.com, netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com References: <000000000000734f2505ac0f2426@google.com> <000000000000f7ec6f05ac91c11d@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <000000000000f7ec6f05ac91c11d@google.com> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 10, 2020 at 08:35:08PM -0700, syzbot wrote: > syzbot has bisected this issue to: > > commit 6a3c7f5c87854e948c3c234e5f5e745c7c553722 > Author: Nikolay Borisov > Date: Thu May 28 08:05:13 2020 +0000 > > btrfs: don't balance btree inode pages from buffered write path This does not make sense wrt use-after-free in HCI, which is completely unrelated subsystem. The patch removes a call to function doing some potentially heavy work, so this likely affects timing and making the bisection unreliable.