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=-6.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS 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 B142CC433E0 for ; Mon, 29 Jun 2020 21:07:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8E5E6206A1 for ; Mon, 29 Jun 2020 21:07:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593464843; bh=luNaPCU/6jbnS0K+V5U2aqJY+/BTW9KAGTO5MmkTewg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=qqIQGEjsqThQceWEsLcIzFlkrgj2vXWMm4eukB5K2Tt16vhqwYTfsqfS2911IZnBY Jfr4IMkUwL/xu3APLn0nCKsLd63w0NYc6LJ35ik4FXdVuYM7iTRxhMdP+YqVntEdUt tmOuwI1J+ds/KM5VKD7NDV0xJj5SM6/oNKMxdXdU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390365AbgF2VHW (ORCPT ); Mon, 29 Jun 2020 17:07:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:53746 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730953AbgF2TKR (ORCPT ); Mon, 29 Jun 2020 15:10:17 -0400 Received: from gmail.com (unknown [104.132.1.76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0D75125598; Mon, 29 Jun 2020 16:42:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593448949; bh=luNaPCU/6jbnS0K+V5U2aqJY+/BTW9KAGTO5MmkTewg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=xVG63WHkl2xs6+ia1HETs24YSoPxEOtOo15i0bFAo8HQPhr0Anl1yaLLPGXv6teOz fFNJADDTapRPEgPSm8b1NGC0958Mp8t6wlOsYCdm4eWlA/3LwvRaVZ2HJVdBnjd7Bb 8wQc3cho/y49Go37ii4Z0xAIcUtAP++zIf96px/A= Date: Mon, 29 Jun 2020 09:42:27 -0700 From: Eric Biggers To: syzbot Cc: bp@alien8.de, hpa@zytor.com, linux-kernel@vger.kernel.org, luto@kernel.org, mingo@redhat.com, syzkaller-bugs@googlegroups.com, tglx@linutronix.de, x86@kernel.org Subject: Re: BUG: unable to handle kernel NULL pointer dereference in __syscall_return_slowpath Message-ID: <20200629164227.GB1752982@gmail.com> References: <00000000000077c48b05a93b96fa@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <00000000000077c48b05a93b96fa@google.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 29, 2020 at 09:31:16AM -0700, syzbot wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit: 4e99b321 Merge tag 'nfs-for-5.8-2' of git://git.linux-nfs... > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=116abdd3100000 > kernel config: https://syzkaller.appspot.com/x/.config?x=bf3aec367b9ab569 > dashboard link: https://syzkaller.appspot.com/bug?extid=95910cea1a7ad8850a0f > compiler: gcc (GCC) 10.1.0-syz 20200507 > userspace arch: i386 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17020755100000 Looks like ioctl$FBIOPUT_VSCREENINFO on /dev/fb0 striking again. There are like 20-30 open syzbot reports for this. See https://lkml.kernel.org/lkml/000000000000ff323f05a053100c@google.com/T/#u for some previous discussion. #syz dup: general protection fault in syscall_return_slowpath