From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965842Ab2C3VTo (ORCPT ); Fri, 30 Mar 2012 17:19:44 -0400 Received: from mail-gy0-f174.google.com ([209.85.160.174]:46401 "EHLO mail-gy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965765Ab2C3VTR (ORCPT ); Fri, 30 Mar 2012 17:19:17 -0400 Message-Id: <20120330194833.995913606@linuxfoundation.org> User-Agent: quilt/0.60-19.1 Date: Fri, 30 Mar 2012 12:49:16 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Sasha Levin , Thomas Gleixner Subject: [ 051/175] ntp: Fix integer overflow when setting time In-Reply-To: <20120330195801.GA31806@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sasha Levin commit a078c6d0e6288fad6d83fb6d5edd91ddb7b6ab33 upstream. 'long secs' is passed as divisor to div_s64, which accepts a 32bit divisor. On 64bit machines that value is trimmed back from 8 bytes back to 4, causing a divide by zero when the number is bigger than (1 << 32) - 1 and all 32 lower bits are 0. Use div64_long() instead. Signed-off-by: Sasha Levin Cc: johnstul@us.ibm.com Link: http://lkml.kernel.org/r/1331829374-31543-2-git-send-email-levinsasha928@gmail.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- kernel/time/ntp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -275,7 +275,7 @@ static inline s64 ntp_update_offset_fll( time_status |= STA_MODE; - return div_s64(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs); + return div64_long(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs); } static void ntp_update_offset(long offset)