From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:33978 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727142AbeLKPpc (ORCPT ); Tue, 11 Dec 2018 10:45:32 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Linus Torvalds Subject: [PATCH 4.4 25/91] unifdef: use memcpy instead of strncpy Date: Tue, 11 Dec 2018 16:40:44 +0100 Message-Id: <20181211151607.816589545@linuxfoundation.org> In-Reply-To: <20181211151606.026852373@linuxfoundation.org> References: <20181211151606.026852373@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Linus Torvalds commit 38c7b224ce22c25fed04007839edf974bd13439d upstream. New versions of gcc reasonably warn about the odd pattern of strncpy(p, q, strlen(q)); which really doesn't make sense: the strncpy() ends up being just a slow and odd way to write memcpy() in this case. There was a comment about _why_ the code used strncpy - to avoid the terminating NUL byte, but memcpy does the same and avoids the warning. Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- scripts/unifdef.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/scripts/unifdef.c +++ b/scripts/unifdef.c @@ -395,7 +395,7 @@ usage(void) * When we have processed a group that starts off with a known-false * #if/#elif sequence (which has therefore been deleted) followed by a * #elif that we don't understand and therefore must keep, we edit the - * latter into a #if to keep the nesting correct. We use strncpy() to + * latter into a #if to keep the nesting correct. We use memcpy() to * overwrite the 4 byte token "elif" with "if " without a '\0' byte. * * When we find a true #elif in a group, the following block will @@ -450,7 +450,7 @@ static void Idrop (void) { Fdrop(); ign static void Itrue (void) { Ftrue(); ignoreon(); } static void Ifalse(void) { Ffalse(); ignoreon(); } /* modify this line */ -static void Mpass (void) { strncpy(keyword, "if ", 4); Pelif(); } +static void Mpass (void) { memcpy(keyword, "if ", 4); Pelif(); } static void Mtrue (void) { keywordedit("else"); state(IS_TRUE_MIDDLE); } static void Melif (void) { keywordedit("endif"); state(IS_FALSE_TRAILER); } static void Melse (void) { keywordedit("endif"); state(IS_FALSE_ELSE); }