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=-5.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS autolearn=unavailable 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 67053C43219 for ; Tue, 30 Apr 2019 12:58:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 40B2021670 for ; Tue, 30 Apr 2019 12:58:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727036AbfD3M6v (ORCPT ); Tue, 30 Apr 2019 08:58:51 -0400 Received: from mx2.suse.de ([195.135.220.15]:60602 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726264AbfD3M6v (ORCPT ); Tue, 30 Apr 2019 08:58:51 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id B8045ACC5; Tue, 30 Apr 2019 12:58:49 +0000 (UTC) Message-ID: <1556629116.20085.32.camel@suse.com> Subject: Re: KASAN: invalid-free in disconnect_rio From: Oliver Neukum To: syzbot , miquel@df.uba.ar, andreyknvl@google.com, syzkaller-bugs@googlegroups.com, gregkh@linuxfoundation.org, rio500-users@lists.sourceforge.net, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Date: Tue, 30 Apr 2019 14:58:36 +0200 In-Reply-To: <0000000000008d15ee058653b53e@google.com> References: <0000000000008d15ee058653b53e@google.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Fr, 2019-04-12 at 04:36 -0700, syzbot wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit: 9a33b369 usb-fuzzer: main usb gadget fuzzer driver > git tree: https://github.com/google/kasan/tree/usb-fuzzer > console output: https://syzkaller.appspot.com/x/log.txt?x=174ce2e3200000 > kernel config: https://syzkaller.appspot.com/x/.config?x=23e37f59d94ddd15 > dashboard link: https://syzkaller.appspot.com/bug?extid=35f04d136fc975a70da4 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=138150f3200000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1290c22d200000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+35f04d136fc975a70da4@syzkaller.appspotmail.com > > usb 6-1: USB disconnect, device number 2 > rio500 3-1:0.110: USB Rio disconnected. > usb 4-1: USB disconnect, device number 2 > ================================================================== > usb 1-1: USB disconnect, device number 2 > BUG: KASAN: double-free or invalid-free in slab_free mm/slub.c:3003 [inline] > BUG: KASAN: double-free or invalid-free in kfree+0xce/0x290 mm/slub.c:3958 > usb 2-1: USB disconnect, device number 2 > Try as I might, I don't understand this. I can see a memory leak, but not a double free. Regards Oliver