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=-8.3 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 114F2C3A59D for ; Mon, 19 Aug 2019 12:18:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BD4CA20851 for ; Mon, 19 Aug 2019 12:18:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Kmou11VE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727259AbfHSMSD (ORCPT ); Mon, 19 Aug 2019 08:18:03 -0400 Received: from mail-pf1-f169.google.com ([209.85.210.169]:45419 "EHLO mail-pf1-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727084AbfHSMSD (ORCPT ); Mon, 19 Aug 2019 08:18:03 -0400 Received: by mail-pf1-f169.google.com with SMTP id w26so1068374pfq.12 for ; Mon, 19 Aug 2019 05:18:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=o94mO5oDmPFzb2RFrcERpL0IeTzi6a9GdDU8DyS+zvY=; b=Kmou11VEcqH2kZQif1grO/nXHzAopJVeKj1VW+wwT6yM6e2X1Lh7HhK3Bkn+U+vfBr dPuln8X7iL3xQyfXWRFg5uoMMB2qbvOxG6u9rrgn3cFPA62K6VZ9cYE4tTzIfoCSdIlD VZSj3VYayGvUiiqMvTyrAKHKuF82MGIve/pDKhDK3Diqnp/qiXRX9SvivR1+JIFiUpI1 Y5+PqIq/kJzaSklw0zRHcqZZV20EMJrG+qrsUp8WsBiiGJO2Yy8XR1xJITMQqgCs8X/Z Xz95FAOx+hu0AXM5xgxXcePqMmJR6YBKNAV2PULY0IxGFsabh9BL0phGCJG/Zi/fE6oq 7cAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=o94mO5oDmPFzb2RFrcERpL0IeTzi6a9GdDU8DyS+zvY=; b=OUbmNekOK6E3HceKAu/bVlzKSqsCprSRgeL+8+TuzMM/ZX3/tBSE7CtxpFtnd6S28g GKS1sANGOQ6lqYHrcZX6LkHKMIGrgeiKisIdmRGbbP8M2uJE8sLatjYSIA37JJuGaUmp Ro9NtdWINZgPqpjlwIreYp0wqqVUGMAb1iONu+MwTZo/Rjtk+dkebzoVftfDwC+fPLOj /uzNMugT1xHa9muKIp3KCyZkIWg1Fqi02tM12HrHIWXklz/uTA2p5z/ue4r8INnIHrVL gsmkj54/kWH7o6USFpR6LeQdUa/fZ791roaHqDXDK6FXb88sEoWQ4BKL/0X4YntUSiuU 4tug== X-Gm-Message-State: APjAAAV47B+ehRIa1GThojKaPSK2Pcqtjr055+UalXxN1f4M9ArtkJQ1 7SPv4/3GaK9e9zY+ruEbQEhul29n7Iiv2hCjyWfxPA== X-Google-Smtp-Source: APXvYqw/Hpkg4QomP7PTfbBI8aTx5sIeOCuaYixMi8G2VuDdWEDzdRkTGvs7l8eXQ2yuFzzGYlyOehMiZIa68foe4C0= X-Received: by 2002:a63:3006:: with SMTP id w6mr19802785pgw.440.1566217081919; Mon, 19 Aug 2019 05:18:01 -0700 (PDT) MIME-Version: 1.0 References: <000000000000a59094059013dd63@google.com> <1565875886.5780.7.camel@suse.com> In-Reply-To: <1565875886.5780.7.camel@suse.com> From: Andrey Konovalov Date: Mon, 19 Aug 2019 14:17:50 +0200 Message-ID: Subject: Re: divide error in usbtmc_generic_read To: Oliver Neukum Cc: syzbot , syzkaller-bugs , steve_bayless@keysight.com, Greg Kroah-Hartman , guido.kiener@rohde-schwarz.com, USB list Content-Type: text/plain; charset="UTF-8" Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Thu, Aug 15, 2019 at 3:31 PM Oliver Neukum wrote: > > Am Mittwoch, den 14.08.2019, 06:38 -0700 schrieb syzbot: > > syzbot has tested the proposed patch but the reproducer still triggered > > crash: > > KASAN: use-after-free Read in usbtmc_disconnect > > I am afraid that is a difficiency in KASAN that should be fixed. > Is the class of the error compared if I leave in more of the > original bug report? Actually the ID is still there, so it really > should return an inconclusive in these cases. I don't get this, what kind of deficiency do you mean? Anyway, looks like I was wrong, the reported use-after-free is caused by an incomplete fix, and setting the right retcode fixes the use-after-free.