From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk0-f198.google.com (mail-qk0-f198.google.com [209.85.220.198]) by kanga.kvack.org (Postfix) with ESMTP id 89F826B02B4 for ; Fri, 11 Aug 2017 19:35:56 -0400 (EDT) Received: by mail-qk0-f198.google.com with SMTP id q66so24728235qki.1 for ; Fri, 11 Aug 2017 16:35:56 -0700 (PDT) Received: from mail-qt0-f182.google.com (mail-qt0-f182.google.com. [209.85.216.182]) by mx.google.com with ESMTPS id r77si106195qkl.85.2017.08.11.16.35.55 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 11 Aug 2017 16:35:55 -0700 (PDT) Received: by mail-qt0-f182.google.com with SMTP id s6so29237250qtc.1 for ; Fri, 11 Aug 2017 16:35:55 -0700 (PDT) Subject: Re: [kernel-hardening] [PATCH v5 00/10] Add support for eXclusive Page Frame Ownership References: <20170809200755.11234-1-tycho@docker.com> From: Laura Abbott Message-ID: <9b3d80f0-7625-a0dc-cb00-cf0e940015b1@redhat.com> Date: Fri, 11 Aug 2017 16:35:52 -0700 MIME-Version: 1.0 In-Reply-To: <20170809200755.11234-1-tycho@docker.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Tycho Andersen , linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, kernel-hardening@lists.openwall.com, Marco Benatto , Juerg Haefliger On 08/09/2017 01:07 PM, Tycho Andersen wrote: > Hi all, > > Here's a v5 of the XPFO set. Changes from v4 are: > > * huge pages support actually works now on x86 > * arm64 support, which boots on several different arm64 boards > * tests for hugepages support as well via LKDTM (thanks Kees for suggesting how > to make this work) > > Patch 2 contains some potentially controversial stuff, exposing the cpa_lock > and lifting some other static functions out; there is probably a better way to > do this, thoughts welcome. > > Still to do are: > > * get it to work with non-64k pages on ARM > * get rid of the BUG()s, in favor or WARN or similar > * other things people come up with in this review > > Please have a look. Thoughts welcome! > I gave this a quick test on my arm64 machine and I see faults once we hit userspace: [ 4.439714] Unhandled fault: TLB conflict abort (0x96000030) at 0xffff800391440090 [ 4.447357] Internal error: : 96000030 [#1] SMP [ 4.451875] Modules linked in: [ 4.454924] CPU: 2 PID: 184 Comm: systemd Tainted: G W 4.13.0-rc4-xpfo+ #63 [ 4.462989] Hardware name: AppliedMicro X-Gene Mustang Board/X-Gene Mustang Board, BIOS 3.06.12 Aug 12 2016 [ 4.472698] task: ffff8003e8d9fb00 task.stack: ffff8003f9fbc000 [ 4.478602] PC is at copy_page+0x48/0x110 [ 4.482601] LR is at __cpu_copy_user_page+0x28/0x48 I'll have to give this a closer look to see what's going on with the TLB flushing. Thanks, Laura > Previously: http://www.openwall.com/lists/kernel-hardening/2017/06/07/24 > > Tycho > > Juerg Haefliger (8): > mm, x86: Add support for eXclusive Page Frame Ownership (XPFO) > swiotlb: Map the buffer if it was unmapped by XPFO > arm64: Add __flush_tlb_one() > arm64/mm: Add support for XPFO > arm64/mm: Disable section mappings if XPFO is enabled > arm64/mm: Don't flush the data cache if the page is unmapped by XPFO > arm64/mm: Add support for XPFO to swiotlb > lkdtm: Add test for XPFO > > Tycho Andersen (2): > mm: add MAP_HUGETLB support to vm_mmap > mm: add a user_virt_to_phys symbol > > Documentation/admin-guide/kernel-parameters.txt | 2 + > arch/arm64/Kconfig | 1 + > arch/arm64/include/asm/cacheflush.h | 11 ++ > arch/arm64/include/asm/tlbflush.h | 8 + > arch/arm64/mm/Makefile | 2 + > arch/arm64/mm/dma-mapping.c | 32 ++-- > arch/arm64/mm/flush.c | 5 +- > arch/arm64/mm/mmu.c | 14 +- > arch/arm64/mm/xpfo.c | 160 +++++++++++++++++ > arch/x86/Kconfig | 1 + > arch/x86/include/asm/pgtable.h | 23 +++ > arch/x86/mm/Makefile | 1 + > arch/x86/mm/pageattr.c | 24 +-- > arch/x86/mm/xpfo.c | 153 +++++++++++++++++ > drivers/misc/Makefile | 1 + > drivers/misc/lkdtm.h | 4 + > drivers/misc/lkdtm_core.c | 4 + > drivers/misc/lkdtm_xpfo.c | 62 +++++++ > include/linux/highmem.h | 15 +- > include/linux/mm.h | 2 + > include/linux/xpfo.h | 47 +++++ > lib/swiotlb.c | 3 +- > mm/Makefile | 1 + > mm/mmap.c | 19 +-- > mm/page_alloc.c | 2 + > mm/page_ext.c | 4 + > mm/util.c | 32 ++++ > mm/xpfo.c | 217 ++++++++++++++++++++++++ > security/Kconfig | 19 +++ > 29 files changed, 810 insertions(+), 59 deletions(-) > create mode 100644 arch/arm64/mm/xpfo.c > create mode 100644 arch/x86/mm/xpfo.c > create mode 100644 drivers/misc/lkdtm_xpfo.c > create mode 100644 include/linux/xpfo.h > create mode 100644 mm/xpfo.c > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org