From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751531AbdFFS0U (ORCPT ); Tue, 6 Jun 2017 14:26:20 -0400 Received: from lhrrgout.huawei.com ([194.213.3.17]:28101 "EHLO lhrrgout.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751239AbdFFS0S (ORCPT ); Tue, 6 Jun 2017 14:26:18 -0400 From: Igor Stoppa To: , , CC: , , , , , , , , , , Igor Stoppa Subject: [RFC v5 PATCH 0/4] NOT FOR MERGE - ro protection for dynamic data Date: Tue, 6 Jun 2017 21:24:49 +0300 Message-ID: <20170606182453.32688-1-igor.stoppa@huawei.com> X-Mailer: git-send-email 2.9.3 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.122.225.51] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020201.5936F3C3.0270,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: 263c49cba16d325a7ae76ed65a5dbd4d Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patchset introduces the possibility of protecting memory that has been allocated dynamically. The memory is managed in pools: when a pool is made R/O, all the memory that is part of it, will become R/O. A R/O pool can be destroyed to recover its memory, but it cannot be turned back into R/W mode. This is intentional. This feature is meant for data that doesn't need further modifications, after initialization. An example is provided, showing how to turn into a boot-time option the writable state of the security hooks. Prior to this patch, it was a compile-time option. This is made possible, thanks to Tetsuo Handa's rework of the hooks structure (included in the patchset). Since the previous version, I have applied fixes for all the issues discovered that had a clear resolution: - %p -> pK - make the feature depend on ARCH_HAS_SET_MEMORY - fix the range of the page scanning for hardened user copy - fixed pointer checking for NULL dereferencing And a couple of issues I found myself: - return NULL in case someone asks memory from a locked pool - turn the "protected" flag into atomic type Still open (at least I didn't get the impression there was a closure): - need for specific __PMALLOC_ALIGNED ? - is it really needed to unprotect a pool? can't it wait for the implementation of write-seldom? Igor Stoppa (3): Protectable Memory Allocator Protectable Memory Allocator - Debug interface Make LSM Writable Hooks a command line option Tetsuo Handa (1): LSM: Convert security_hook_heads into explicit array of struct list_head include/linux/lsm_hooks.h | 412 ++++++++++++++++++++--------------------- include/linux/page-flags.h | 2 + include/linux/pmalloc.h | 20 ++ include/trace/events/mmflags.h | 1 + init/main.c | 2 + mm/Kconfig | 11 ++ mm/Makefile | 1 + mm/pmalloc.c | 340 ++++++++++++++++++++++++++++++++++ mm/usercopy.c | 24 ++- security/security.c | 49 +++-- 10 files changed, 632 insertions(+), 230 deletions(-) create mode 100644 include/linux/pmalloc.h create mode 100644 mm/pmalloc.c -- 2.9.3