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=-11.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 5AE29C433E9 for ; Fri, 12 Mar 2021 09:24:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 218EA64FDA for ; Fri, 12 Mar 2021 09:24:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232432AbhCLJYG (ORCPT ); Fri, 12 Mar 2021 04:24:06 -0500 Received: from mail.kernel.org ([198.145.29.99]:46184 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232818AbhCLJXl (ORCPT ); Fri, 12 Mar 2021 04:23:41 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4B66964F09; Fri, 12 Mar 2021 09:14:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615540446; bh=AJdZGmDhGxx5TmaTmC4ylxcirQVAw3oTrq1wVYQkWIc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=tIzgn2RzuDUqFs6JA8jPyB1rKqAlw0BdycnN723xfNMkojnk98D47MLvUsxzpM9FZ bvXz4KAh4qTRTj7gs6mi1rTb++iAieW4yVVmrW6p8O3qSghoTf3wz2hKWLASqXee6m ktqMWPjTUi1O3XLUbHBs3zyQUhqGbtOtAtNUo3cAxnS2WKFcHd/8rqF7QjQeQvJIXC CywVmBYGkJV2BkmSjyom3nYbsxUNUsNE2ALKrrS1iiQdmrPoRsOxYFZqalqny0qqAY 4p0BP3NS3B+m89goRXqgPpfbJhr6/lqTKLRJMWm05e+kI/hCY/jGYKPk/4s8SS0th9 z3E+Iyp7GfIrQ== Date: Fri, 12 Mar 2021 10:13:55 +0100 From: Wolfram Sang To: syzbot Cc: linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com Subject: Re: [syzbot] WARNING in __i2c_transfer Message-ID: <20210312091345.GA5294@ninjato> References: <000000000000f564d305bd521b83@google.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="b5gNqxB1S1yM7hjW" Content-Disposition: inline In-Reply-To: <000000000000f564d305bd521b83@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org --b5gNqxB1S1yM7hjW Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Mar 11, 2021 at 11:47:17PM -0800, syzbot wrote: > Hello, >=20 > syzbot found the following issue on: >=20 > HEAD commit: 28806e4d Merge tag 'media/v5.12-2' of git://git.kernel.or= g.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=3D11192342d00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=3D6bcf96204c1b8= e77 > dashboard link: https://syzkaller.appspot.com/bug?extid=3Dffb0b3ffa6cfbc7= d7b3f > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=3D1083223ad00= 000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=3D14345f0ad00000 >=20 > IMPORTANT: if you fix the issue, please add the following tag to the comm= it: > Reported-by: syzbot+ffb0b3ffa6cfbc7d7b3f@syzkaller.appspotmail.com >=20 > ------------[ cut here ]------------ > WARNING: CPU: 1 PID: 8406 at drivers/i2c/i2c-core-base.c:2021 __i2c_trans= fer+0xa87/0x17d0 drivers/i2c/i2c-core-base.c:2021 Yes, it can be argued that userspace should not be able to trigger a WARNING. For in-kernel users, the WARN is really helpful, though. I will add sanity checks much earlier to i2c-dev.c which will not be that noisy. --b5gNqxB1S1yM7hjW Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAmBLMNMACgkQFA3kzBSg KbY81RAAphTsoj9bYx4Q9CcF+BaB/bjhrPBYMe0/7FklyN2+QHzmJJw003YSMihi Nwv9MvnJzoCSKNkkq9gwNA7DTcyNJ3z9ahepRdrRjlzsPbSfCrlMPilL6uIV1AKJ NSC3r4+u+nIop+aaC8lYKydsYWrl/sjsgVRb204Ywv68BnESUGrGSYsWAsqdljpG B6ReFpkygBzsRu4EMGRMD5z/nwt00h1sXCmgj/lsTkVxj/u3Lr+7PlQnNPlDxJVU gX1n2JPKOX50ALnay1crEvCkGbe1mkXmTdGHf6Y+8+d+vhAdORNnTosKPxWQVZ+H pWxcajhH2z1/dr/B79pZ/hZhTiIbkM6o3pGH3X7y5rSmB3RdPWUp15hHGCllAbJ3 cUAICT8coc8kIgQfkidbNDaDuVnaXDlkeqbH+o/7eDXrfmPJXHxiCf4H6nSDFRL4 G+D3u8IGExEDGQ7iMJh1tHNuuwIJcKNy2I4YejnzmZLZnGsRXFJU2YDYJewfaktJ 49HhEPYoNhUbFTkfXYbMtcP959H5nGXPsb5S5Rll6DodDabtMNbjNiV3NjAGgM5z cjCtYcRE3RGzoDyI23MJcintgbHTIlNWWLGT6iaRBmNJKSXYiiQBB1pr8BASIWku AbPJ8rCLDHPG1KqVv3BouN4k7H79Ey80XYg2tMYa4nYLVDh9wTc= =pZs9 -----END PGP SIGNATURE----- --b5gNqxB1S1yM7hjW--