From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754404Ab1AKIHm (ORCPT ); Tue, 11 Jan 2011 03:07:42 -0500 Received: from mprc.pku.edu.cn ([162.105.203.9]:48777 "EHLO mprc.pku.edu.cn" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752293Ab1AKIHg (ORCPT ); Tue, 11 Jan 2011 03:07:36 -0500 From: "Guan Xuetao" To: "Arnd Bergmann" , , Subject: [PATCH] asm-generic headers: add arch-specific __strnlen_user calling in uaccess.h Date: Tue, 11 Jan 2011 16:07:27 +0800 Message-ID: <008801cbb166$96cd0430$c4670c90$@mprc.pku.edu.cn> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 14.0 Thread-Index: AcuxZnPa0VBA8k7HRZm0eyNMm3Ehzg== Content-Language: zh-cn Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Guan Xuetao This patch changes the implementation of strnlen_user in include/asm-generic/uaccess.h. Originally, it calls strlen() function directly, which may not correctly handle the access of user space in most mmu-enabled architectures. New __strnlen_user is added for using as an architecture specific function. Signed-off-by: Guan Xuetao --- include/asm-generic/uaccess.h | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-) diff --git a/include/asm-generic/uaccess.h b/include/asm-generic/uaccess.h index b218b85..ac68c99 100644 --- a/include/asm-generic/uaccess.h +++ b/include/asm-generic/uaccess.h @@ -288,14 +288,16 @@ strncpy_from_user(char *dst, const char __user *src, long count) * * Return 0 on exception, a value greater than N if too long */ -#ifndef strnlen_user +#ifndef __strnlen_user +#define __strnlen_user strnlen +#endif + static inline long strnlen_user(const char __user *src, long n) { if (!access_ok(VERIFY_READ, src, 1)) return 0; - return strlen((void * __force)src) + 1; + return __strnlen_user(src, n); } -#endif static inline long strlen_user(const char __user *src) {