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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,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 8D6F3CA9EA0 for ; Mon, 28 Oct 2019 07:32:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5747820873 for ; Mon, 28 Oct 2019 07:32:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="pk7fgpH4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732985AbfJ1Hc6 (ORCPT ); Mon, 28 Oct 2019 03:32:58 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:41794 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730235AbfJ1Hc5 (ORCPT ); Mon, 28 Oct 2019 03:32:57 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x9S7T95S159059; Mon, 28 Oct 2019 07:32:38 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2019-08-05; bh=jOkh6Pes5+Pp0tUmWlRazAo1B1JEuBBAsR0+VNYAQAM=; b=pk7fgpH48/L+eltaBuV5griotY/UYEqNr9Eyc1AX7vdmJnFrKWUmJQwWNMdT63jAYXaw GsmztkzzCVy6hVJ16MlcwUE8SOavTc5qceh0Ybro0eszcrQFYKdD0Y4e4UuGc3/rXh6O L9CtQGduzNUv8GJgGne4ULtv05EIhpUdJkv5fnRCQMLcg+uEHJ9RwmLU8Im+zVSeUbeX UUCSPmpRnyJ1iG1qxJHSg4AhIhGBnr0jJmJIdNR11h6P5HatJx+clgqrhKX8iO7N8+tW NqAmhl2keQ3PPxS47qMQytyCEJQeNhZUrb0M13DHkgWoT1sqgex7uqupGHRu52ajBWZl pw== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by userp2120.oracle.com with ESMTP id 2vvumf4wpe-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 28 Oct 2019 07:32:38 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x9S7Sk7e186426; Mon, 28 Oct 2019 07:30:37 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserp3030.oracle.com with ESMTP id 2vwakxgx4v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 28 Oct 2019 07:30:37 +0000 Received: from abhmp0010.oracle.com (abhmp0010.oracle.com [141.146.116.16]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id x9S7UXG0015943; Mon, 28 Oct 2019 07:30:34 GMT Received: from kadam (/41.57.98.10) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 28 Oct 2019 00:30:32 -0700 Date: Mon, 28 Oct 2019 10:30:25 +0300 From: Dan Carpenter To: Joe Perches Cc: Julia Lawall , Andrew Morton , LKML , Dan Carpenter , Thomas Gleixner , Kees Cook , zhanglin Subject: Re: [PATCH] kernel: sys.c: Avoid copying possible padding bytes in copy_to_user Message-ID: <20191028073025.GB1944@kadam> References: <92212e57d45f4410be654183f5dcb1e98d636ef2.camel@perches.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <92212e57d45f4410be654183f5dcb1e98d636ef2.camel@perches.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9423 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=623 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910280075 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9423 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=726 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910280075 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We should be able to use memzero_explicit(), right? The fact that we memset() can't be used to prevent information leaks has always worried me. Everyone predicted that we would have bugs like this where memset doesn't work as expected. regards, dan carpenter