From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932872Ab1JDQoS (ORCPT ); Tue, 4 Oct 2011 12:44:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44607 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932808Ab1JDQoN (ORCPT ); Tue, 4 Oct 2011 12:44:13 -0400 From: Mark Salter To: linux-kernel@vger.kernel.org Cc: linux-arch@vger.kernel.org, Mark Salter Subject: [PATCH v4 01/24] fix default __strnlen_user macro Date: Tue, 4 Oct 2011 12:43:38 -0400 Message-Id: <1317746641-26725-2-git-send-email-msalter@redhat.com> In-Reply-To: <1317746641-26725-1-git-send-email-msalter@redhat.com> References: <1317746641-26725-1-git-send-email-msalter@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The existing __strnlen_user macro simply resolved to strnlen. However, the count returned by strnlen_user should include the NULL byte. This patch fixes the __strnlen_user macro to include the NULL byte in the count. Signed-off-by: Mark Salter Acked-by: Arnd Bergmann --- include/asm-generic/uaccess.h | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/include/asm-generic/uaccess.h b/include/asm-generic/uaccess.h index ac68c99..9788568 100644 --- a/include/asm-generic/uaccess.h +++ b/include/asm-generic/uaccess.h @@ -289,9 +289,14 @@ 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 -#define __strnlen_user strnlen +#define __strnlen_user(s, n) (strnlen((s), (n)) + 1) #endif +/* + * Unlike strnlen, strnlen_user includes the nul terminator in + * its returned count. Callers should check for a returned value + * greater than N as an indication the string is too long. + */ static inline long strnlen_user(const char __user *src, long n) { if (!access_ok(VERIFY_READ, src, 1)) -- 1.7.6.2