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=-5.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED, USER_AGENT_SANE_1 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 5D1FBC432C3 for ; Fri, 15 Nov 2019 07:43:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 309A520740 for ; Fri, 15 Nov 2019 07:43:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="ZH1elWzw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726958AbfKOHnl (ORCPT ); Fri, 15 Nov 2019 02:43:41 -0500 Received: from userp2130.oracle.com ([156.151.31.86]:52516 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726182AbfKOHnk (ORCPT ); Fri, 15 Nov 2019 02:43:40 -0500 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id xAF7d6ib109361; Fri, 15 Nov 2019 07:42:15 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=g8uThl8dkg+cj+2qFvpX4UHz2ZpNIXnP5NoBMB9GLqg=; b=ZH1elWzwIglBNSmcB5X+wP0yf/LmUt1gwQ+BKmeAdqrKDHpR/B3VCP4gZCn+KMqZMs9o VGHfMyBeXTtqPWxiohoxTx5o7AfdSifH5au/Bm2F7yVdLrt3SFvNiIu3Bmkqjm2Sh1FQ PezEvg+YOhnSG5jhEdCiE5XV3iqHQhA9DYdcDAsrS43yoJzICjQ8HGET00MD1DelpZ0X M+etngT3aPLHcBKyusqkOVVWdOf2MdHXjY7n+YHRfOY5MAx7YFmUmeiVh70iLUsFIgRv KCSZWILoTsg5EdUjbLSi1zTrjbonXuFcKjTLQm2+RS4ZrBxPO9YIBIsDHfdo4Swj/sjF Qg== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by userp2130.oracle.com with ESMTP id 2w9gxphk9u-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 15 Nov 2019 07:42:15 +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 xAF7brgj141487; Fri, 15 Nov 2019 07:40:14 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3030.oracle.com with ESMTP id 2w9h149024-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 15 Nov 2019 07:40:14 +0000 Received: from abhmp0008.oracle.com (abhmp0008.oracle.com [141.146.116.14]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id xAF7eBZl031896; Fri, 15 Nov 2019 07:40:12 GMT Received: from kadam.lan (/129.205.23.165) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 14 Nov 2019 23:40:11 -0800 Date: Fri, 15 Nov 2019 10:40:03 +0300 From: Dan Carpenter To: Kees Cook Cc: Greg Kroah-Hartman , devel@driverdev.osuosl.org, Florian Schilhabel , kernel-hardening@lists.openwall.com, linux-kernel@vger.kernel.org, Romain Perier , Larry Finger Subject: Re: [PATCH] staging: rtl*: Remove tasklet callback casts Message-ID: <20191115074003.GB19101@kadam.lan> References: <201911142135.5656E23@keescook> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201911142135.5656E23@keescook> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9441 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=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1911140001 definitions=main-1911150069 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9441 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=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1911140001 definitions=main-1911150069 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 14, 2019 at 09:39:00PM -0800, Kees Cook wrote: > In order to make the entire kernel usable under Clang's Control Flow > Integrity protections, function prototype casts need to be avoided > because this will trip CFI checks at runtime (i.e. a mismatch between > the caller's expected function prototype and the destination function's > prototype). Many of these cases can be found with -Wcast-function-type, > which found that the rtl wifi drivers had a bunch of needless function > casts. Remove function casts for tasklet callbacks in the various drivers. > > Signed-off-by: Kees Cook Clang should treat void pointers as a special case. If void pointers are bad, surely replacing them with unsigned long is even more ambigous and worse. regards, dan carpenter