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=-3.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED 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 3AA1DC04AB1 for ; Thu, 9 May 2019 19:40:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EB24A2177E for ; Thu, 9 May 2019 19:40:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=paul-moore-com.20150623.gappssmtp.com header.i=@paul-moore-com.20150623.gappssmtp.com header.b="wPsup362" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726907AbfEITkx (ORCPT ); Thu, 9 May 2019 15:40:53 -0400 Received: from mail-lj1-f195.google.com ([209.85.208.195]:34596 "EHLO mail-lj1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726658AbfEITkx (ORCPT ); Thu, 9 May 2019 15:40:53 -0400 Received: by mail-lj1-f195.google.com with SMTP id j24so2259447ljg.1 for ; Thu, 09 May 2019 12:40:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=paul-moore-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Ch5HLiNUbdzzp7mAUxeBmeNjCFg/GpZc2QwMMzZyJng=; b=wPsup362DAd3psjSHvLU2BYR3/+cIDk35eRFxJv7OPLf4B8DBxK2P1pTH73GwbPBpL DBo/pH0buXy6/OQbqrgDUAeibeKLDvf0PaO+qVg6j6LcOHTT42pbWhmDoHwJnusB2/B3 +3oEeZnBwBljOkFfIGk3/XpKAH5vbCn1Rp0NegsLz7zWvyhV2OryUjcT8w85j31OW8Q+ gVqCTZWYE61xodZLRna0NxS4FS2QQneroTYWpueE02IeWADyXmztqRnFBPSyF/xCfJPW Ei/tRFtWVvtX4AlJ6PulL161qULpVK8Gadg7pU88J1B+eJ+v6O2Wx3iPYJFxaY/TKYdR gsHQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Ch5HLiNUbdzzp7mAUxeBmeNjCFg/GpZc2QwMMzZyJng=; b=gHtKr/RuqKRN5XqCPCOtXOR/k+IsP4iO7SJrPN99h57IfvnFCu5Z1kWNEs2/Ji75+s pRk34eSgFRk4tMP2TeofYa5BTiVwXZp3mawtcTmRr4UxPAntw+2zxDXJUHm8raeShfwi F5//SwrAvzRN3Bcm+8OM3nuDMVPgyV615QzpkS9BsGNhnXLSH6bqUyt0U2w4TlCTYRDx NEiXkoUJ45AjN+CgAtk//JbMkDm+uTSdPbCpY8co1VGZJmmfUxT+aPqu9QLlreUmxw07 7TVKKsixAYBafZbXejLqMXU0t2KCUPOXgqKzhNyhBsKvOd8jpzf/AJdvUpO8SnqzeKzK OpNQ== X-Gm-Message-State: APjAAAW39Y4TmBsgMOjIDi7jx6OLBbzM69wvj+nwoIA6x/AQnXokNGhq OcZAWlIQu6we8HGfXhFW9zaY+ZWWPVHHo9lrtz55YrKAtQ== X-Google-Smtp-Source: APXvYqwxm6N56BeGMIOKk8zY4FBZH0CSAHQssmwSOJvYO3VgbeLoLoGm/zXMN3y0gspjWxfItrilybhsu1plcWp7nY0= X-Received: by 2002:a2e:9d0a:: with SMTP id t10mr3432630lji.95.1557430850530; Thu, 09 May 2019 12:40:50 -0700 (PDT) MIME-Version: 1.0 References: <1557296477-4694-1-git-send-email-hofrat@osadl.org> <20190509001345.GA23407@osadl.at> In-Reply-To: <20190509001345.GA23407@osadl.at> From: Paul Moore Date: Thu, 9 May 2019 15:40:39 -0400 Message-ID: Subject: Re: [PATCH RFC] selinux: provide __le variables explicitly To: Nicholas Mc Guire Cc: Nicholas Mc Guire , Stephen Smalley , Eric Paris , peter enderborg , selinux@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 8, 2019 at 8:14 PM Nicholas Mc Guire wrote: > On Wed, May 08, 2019 at 05:47:32PM -0400, Paul Moore wrote: > > On Wed, May 8, 2019 at 2:27 AM Nicholas Mc Guire wrote: > > > While the endiannes is being handled properly sparse was unable to verify > > > this due to type inconsistency. So introduce an additional __le32 > > > respectively _le64 variable to be passed to le32/64_to_cpu() to allow > > > sparse to verify proper typing. Note that this patch does not change > > > the generated binary on little-endian systems - on 32bit powerpc it > > > does change the binary. > > > > > > Signed-off-by: Nicholas Mc Guire > > > --- > > > > > > Problem located by an experimental coccinelle script to locate > > > patters that make sparse unhappy (false positives): > > > > > > sparse complaints on different architectures fixed by this patch are: > > > > > > ppc6xx_defconfig > > > CHECK security/selinux/ss/ebitmap.c > > > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > > > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > > > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > > > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > > > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > > > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > > > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > > > > > Little-endian systems: > > > > > > loongson3_defconfig > > > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > > > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > > > > > x86_64_defconfig > > > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > > > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > > > > > Patch was compile-tested with: x86_64_defconfig,loongson3_defconfig (both > > > little-endian) and ppc603_defconfig (big-endian). > > > > > > On little-endian systems the patch has no impact on the generated binary > > > (which is expected) but on the 32bit powerpc it does change the binary > > > which is not expected but since I'm not able to generate the .lst files > > > in security/selinux/ss/ due to the lack of a Makefile it is not clear > > > if this is an unexpected side-effect or due only to the introduction of > > > the additional variables. From my understanding the patch does not change > > > the program logic so if the code was correct on big-endian systems before > > > it should still be correct now. > > > > This is a bit worrisome, but I tend to agree that this patch *should* > > be correct. I'm thinking you're probably right in that the resulting > > binary difference could be due to the extra variable. Have you tried > > any other big-endian arches? > > > > just tried ppc64_defconfig + AUDIT=y, SECURITY=y, SECURITY_NETWORK=y, SECURITY_SELINUX=y > > sparse will complain in the original version about: > CHECK security/selinux/ss/ebitmap.c > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > security/selinux/ss/ebitmap.c:389:28: warning: cast to restricted __le32 > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > security/selinux/ss/ebitmap.c:431:23: warning: cast to restricted __le64 > > which is the same as 32bit ppc - after the patch is applied that is resolved > and and the generated ebitmap.o files are binary identical. > > I just had chosen ppc6xx_defconfig as my big-endian test-target as SELINUX > was on there by default so I assumed it would be the most reasonable > compile-test target. Thanks. I think this is probably safe to merge once the merge window closes. -- paul moore www.paul-moore.com