From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933581AbcAYQz6 (ORCPT ); Mon, 25 Jan 2016 11:55:58 -0500 Received: from mx1.redhat.com ([209.132.183.28]:45344 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932682AbcAYQz4 (ORCPT ); Mon, 25 Jan 2016 11:55:56 -0500 From: Laura Abbott To: Andrew Morton , "Kirill A. Shutemov" , Vlastimil Babka , Michal Hocko Cc: Laura Abbott , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com, Kees Cook Subject: [RFC][PATCH 0/3] Sanitization of buddy pages Date: Mon, 25 Jan 2016 08:55:50 -0800 Message-Id: <1453740953-18109-1-git-send-email-labbott@fedoraproject.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, This is an implementation of page poisoning/sanitization for all arches. It takes advantage of the existing implementation for !ARCH_SUPPORTS_DEBUG_PAGEALLOC arches. This is a different approach than what the Grsecurity patches were taking but should provide equivalent functionality. For those who aren't familiar with this, the goal of sanitization is to reduce the severity of use after free and uninitialized data bugs. Memory is cleared on free so any sensitive data is no longer available. Discussion of sanitization was brough up in a thread about CVEs (lkml.kernel.org/g/<20160119112812.GA10818@mwanda>) I eventually expect Kconfig names will want to be changed and or moved if this is going to be used for security but that can happen later. Credit to Mathias Krause for the version in grsecurity Laura Abbott (3): mm/debug-pagealloc.c: Split out page poisoning from debug page_alloc mm/page_poison.c: Enable PAGE_POISONING as a separate option mm/page_poisoning.c: Allow for zero poisoning Documentation/kernel-parameters.txt | 5 ++ include/linux/mm.h | 13 +++ include/linux/poison.h | 4 + mm/Kconfig.debug | 35 +++++++- mm/Makefile | 5 +- mm/debug-pagealloc.c | 127 +---------------------------- mm/page_alloc.c | 10 ++- mm/page_poison.c | 158 ++++++++++++++++++++++++++++++++++++ 8 files changed, 228 insertions(+), 129 deletions(-) create mode 100644 mm/page_poison.c -- 2.5.0