From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753303AbbHBALZ (ORCPT ); Sat, 1 Aug 2015 20:11:25 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:36057 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751870AbbHBAJt (ORCPT ); Sat, 1 Aug 2015 20:09:49 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Jan Kara" Date: Sun, 02 Aug 2015 01:02:37 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 110/164] x86_64: Fix strnlen_user() to not touch memory after specified maximum In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.70-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Ben Hutchings Inspired by commit f18c34e483ff ("lib: Fix strnlen_user() to not touch memory after specified maximum") upstream. This version of strnlen_user(), no longer present upstream, has a similar off-by-one error. Signed-off-by: Ben Hutchings Cc: Jan Kara --- --- a/arch/x86/lib/usercopy_64.c +++ b/arch/x86/lib/usercopy_64.c @@ -113,7 +113,7 @@ long __strnlen_user(const char __user *s char c; while (1) { - if (res>n) + if (res >= n) return n+1; if (__get_user(c, s)) return 0;