Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755425Ab3CFUry (ORCPT ); Wed, 6 Mar 2013 15:47:54 -0500 Received: from mx1.redhat.com ([209.132.183.28]:21145 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753554Ab3CFUrw (ORCPT ); Wed, 6 Mar 2013 15:47:52 -0500 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 2/4] UAPI: Fix endianness conditionals in linux/acct.h To: torvalds@linux-foundation.org From: David Howells Cc: linux-arch@vger.kernel.org, sfr@canb.auug.org.au, Joakim.Tjernlund@transmode.se, arnd@arndb.de, linux-kernel@vger.kernel.org, akpm@linux-foundation.org Date: Wed, 06 Mar 2013 20:47:43 +0000 Message-ID: <20130306204742.31327.46737.stgit@warthog.procyon.org.uk> In-Reply-To: <20130306204724.31327.43118.stgit@warthog.procyon.org.uk> References: <20130306204724.31327.43118.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.16 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1839 Lines: 46 In the UAPI header files, __BIG_ENDIAN and __LITTLE_ENDIAN must be compared against __BYTE_ORDER in preprocessor conditionals where these are exposed to userspace (that is they're not inside __KERNEL__ conditionals). However, in the main kernel the norm is to check for "defined(__XXX_ENDIAN)" rather than comparing against __BYTE_ORDER and this has incorrectly leaked into the userspace headers. The definition of ACCT_BYTEORDER in linux/acct.h is wrong in this way. Note that userspace will likely interpret this incorrectly as the big-endian variant on little-endian machines - depending on header inclusion order. [!!!] NOTE [!!!] This patch may adversely change the userspace API. It might be better to fix the value of ACCT_BYTEORDER. Signed-off-by: David Howells --- include/uapi/linux/acct.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/include/uapi/linux/acct.h b/include/uapi/linux/acct.h index 11b6ca3..df2f9a0 100644 --- a/include/uapi/linux/acct.h +++ b/include/uapi/linux/acct.h @@ -107,10 +107,12 @@ struct acct_v3 #define ACORE 0x08 /* ... dumped core */ #define AXSIG 0x10 /* ... was killed by a signal */ -#ifdef __BIG_ENDIAN +#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __BIG_ENDIAN : defined(__BIG_ENDIAN) #define ACCT_BYTEORDER 0x80 /* accounting file is big endian */ -#else +#elif defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : defined(__LITTLE_ENDIAN) #define ACCT_BYTEORDER 0x00 /* accounting file is little endian */ +#else +#error unspecified endianness #endif #ifndef __KERNEL__ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/