From: Yu-cheng Yu <yu-cheng.yu@intel.com>
To: Eugene Syromiatnikov <esyr@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>, X86 ML <x86@kernel.org>,
"H. Peter Anvin" <hpa@zytor.com>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
LKML <linux-kernel@vger.kernel.org>,
linux-doc@vger.kernel.org, Linux-MM <linux-mm@kvack.org>,
linux-arch <linux-arch@vger.kernel.org>,
Linux API <linux-api@vger.kernel.org>,
Arnd Bergmann <arnd@arndb.de>,
Balbir Singh <bsingharora@gmail.com>,
Cyrill Gorcunov <gorcunov@gmail.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
Florian Weimer <fweimer@redhat.com>,
"H. J. Lu" <hjl.tools@gmail.com>, Jann Horn <jannh@google.com>,
Jonathan Corbet <corbet@lwn.net>,
Kees Cook <keescook@chromium.org>,
Mike Kravetz <mike.kravetz@oracle.com>,
Nadav Amit <nadav.amit@gmail.com>,
Oleg
Subject: Re: [RFC PATCH v4 24/27] mm/mmap: Create a guard area between VMAs
Date: Wed, 03 Oct 2018 09:40:58 -0700 [thread overview]
Message-ID: <36fa923c4ed6b78517b93475aa2544aa8ba7243c.camel@intel.com> (raw)
In-Reply-To: <20181003163226.GC9449@asgard.redhat.com>
On Wed, 2018-10-03 at 18:32 +0200, Eugene Syromiatnikov wrote:
> On Wed, Oct 03, 2018 at 09:00:04AM -0700, Yu-cheng Yu wrote:
> > On Tue, 2018-10-02 at 22:36 -0700, Andy Lutomirski wrote:
> > > On Tue, Oct 2, 2018 at 9:55 PM Eugene Syromiatnikov <esyr@redhat.com>
> > > wrote:
> > > >
> > > > On Fri, Sep 21, 2018 at 08:03:48AM -0700, Yu-cheng Yu wrote:
> > > > > Create a guard area between VMAs, to detect memory corruption.
> > > >
> > > > Do I understand correctly that with this patch a user space program
> > > > no longer be able to place two mappings back to back? If it is so,
> > > > it will likely break a lot of things; for example, it's a common ring
> > > > buffer implementations technique, to map buffer memory twice back
> > > > to back in order to avoid special handling of items wrapping its end.
> > >
> > > I haven't checked what the patch actually does, but it shouldn't have
> > > any affect on MAP_FIXED or the new no-replace MAP_FIXED variant.
> > >
> > > --Andy
> >
> > I did some mmap tests with/without MAP_FIXED, and it works as intended.
> > In addition to the ring buffer, are there other test cases?
>
> Right, after some more code reading I figured out that it indeed
> shouldn't affect MAP_FIXED, thank you for confirmation.
>
> I'm not sure, however, whether such a change that provides no ability
> to configure or affect it will go well with all the supported
> architectures.
Can we do CONFIG_MMAP_GUARD_GAP?
WARNING: multiple messages have this Message-ID (diff)
From: Yu-cheng Yu <yu-cheng.yu@intel.com>
To: Eugene Syromiatnikov <esyr@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>, X86 ML <x86@kernel.org>,
"H. Peter Anvin" <hpa@zytor.com>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>,
LKML <linux-kernel@vger.kernel.org>,
linux-doc@vger.kernel.org, Linux-MM <linux-mm@kvack.org>,
linux-arch <linux-arch@vger.kernel.org>,
Linux API <linux-api@vger.kernel.org>,
Arnd Bergmann <arnd@arndb.de>,
Balbir Singh <bsingharora@gmail.com>,
Cyrill Gorcunov <gorcunov@gmail.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
Florian Weimer <fweimer@redhat.com>,
"H. J. Lu" <hjl.tools@gmail.com>, Jann Horn <jannh@google.com>,
Jonathan Corbet <corbet@lwn.net>,
Kees Cook <keescook@chromium.org>,
Mike Kravetz <mike.kravetz@oracle.com>,
Nadav Amit <nadav.amit@gmail.com>,
Oleg Nesterov <oleg@redhat.com>, Pavel Machek <pavel@ucw.cz>,
Peter Zijlstra <peterz@infradead.org>,
Randy Dunlap <rdunlap@infradead.org>,
"Ravi V. Shankar" <ravi.v.shankar@intel.com>,
"Shanbhogue, Vedvyas" <vedvyas.shanbhogue@intel.com>
Subject: Re: [RFC PATCH v4 24/27] mm/mmap: Create a guard area between VMAs
Date: Wed, 03 Oct 2018 09:40:58 -0700 [thread overview]
Message-ID: <36fa923c4ed6b78517b93475aa2544aa8ba7243c.camel@intel.com> (raw)
Message-ID: <20181003164058.G3dgYhXFYgttvFx1Kyy5UOnA3y14p20vMQF5_-Yqpy0@z> (raw)
In-Reply-To: <20181003163226.GC9449@asgard.redhat.com>
On Wed, 2018-10-03 at 18:32 +0200, Eugene Syromiatnikov wrote:
> On Wed, Oct 03, 2018 at 09:00:04AM -0700, Yu-cheng Yu wrote:
> > On Tue, 2018-10-02 at 22:36 -0700, Andy Lutomirski wrote:
> > > On Tue, Oct 2, 2018 at 9:55 PM Eugene Syromiatnikov <esyr@redhat.com>
> > > wrote:
> > > >
> > > > On Fri, Sep 21, 2018 at 08:03:48AM -0700, Yu-cheng Yu wrote:
> > > > > Create a guard area between VMAs, to detect memory corruption.
> > > >
> > > > Do I understand correctly that with this patch a user space program
> > > > no longer be able to place two mappings back to back? If it is so,
> > > > it will likely break a lot of things; for example, it's a common ring
> > > > buffer implementations technique, to map buffer memory twice back
> > > > to back in order to avoid special handling of items wrapping its end.
> > >
> > > I haven't checked what the patch actually does, but it shouldn't have
> > > any affect on MAP_FIXED or the new no-replace MAP_FIXED variant.
> > >
> > > --Andy
> >
> > I did some mmap tests with/without MAP_FIXED, and it works as intended.
> > In addition to the ring buffer, are there other test cases?
>
> Right, after some more code reading I figured out that it indeed
> shouldn't affect MAP_FIXED, thank you for confirmation.
>
> I'm not sure, however, whether such a change that provides no ability
> to configure or affect it will go well with all the supported
> architectures.
Can we do CONFIG_MMAP_GUARD_GAP?
next prev parent reply other threads:[~2018-10-03 16:40 UTC|newest]
Thread overview: 142+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-21 15:03 [RFC PATCH v4 00/27] Control Flow Enforcement: Shadow Stack Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 01/27] x86/cpufeatures: Add CPUIDs for Control-flow Enforcement Technology (CET) Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-25 16:27 ` Peter Zijlstra
2018-09-25 16:27 ` Peter Zijlstra
2018-09-25 16:29 ` Yu-cheng Yu
2018-09-25 16:29 ` Yu-cheng Yu
2018-09-28 16:51 ` Borislav Petkov
2018-09-28 16:51 ` Borislav Petkov
2018-09-28 16:56 ` Yu-cheng Yu
2018-09-28 16:56 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 02/27] x86/fpu/xstate: Change some names to separate XSAVES system and user states Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-25 16:37 ` Peter Zijlstra
2018-09-25 16:37 ` Peter Zijlstra
2018-10-02 15:29 ` Borislav Petkov
2018-10-02 15:29 ` Borislav Petkov
2018-10-02 16:21 ` Yu-cheng Yu
2018-10-02 16:21 ` Yu-cheng Yu
2018-10-02 16:30 ` Dave Hansen
2018-10-02 16:30 ` Dave Hansen
2018-10-02 16:37 ` Borislav Petkov
2018-10-02 16:37 ` Borislav Petkov
2018-10-02 16:39 ` Dave Hansen
2018-10-02 16:39 ` Dave Hansen
2018-10-02 16:43 ` Yu-cheng Yu
2018-10-02 16:43 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 03/27] x86/fpu/xstate: Enable XSAVES system states Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-25 17:03 ` Peter Zijlstra
2018-09-25 17:03 ` Peter Zijlstra
2018-09-25 17:23 ` Yu-cheng Yu
2018-09-25 17:23 ` Yu-cheng Yu
2018-10-02 17:15 ` Borislav Petkov
2018-10-02 17:15 ` Borislav Petkov
2018-10-04 15:47 ` Yu-cheng Yu
2018-10-04 15:47 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 04/27] x86/fpu/xstate: Add XSAVES system states for shadow stack Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 05/27] Documentation/x86: Add CET description Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 06/27] x86/cet: Control protection exception handler Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-10-03 10:39 ` Eugene Syromiatnikov
2018-10-03 10:39 ` Eugene Syromiatnikov
2018-10-03 16:11 ` Yu-cheng Yu
2018-10-03 16:11 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 07/27] x86/cet/shstk: Add Kconfig option for user-mode shadow stack Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 08/27] mm: Introduce VM_SHSTK for shadow stack memory Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 09/27] x86/mm: Change _PAGE_DIRTY to _PAGE_DIRTY_HW Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-10-03 13:38 ` Matthew Wilcox
2018-10-03 13:38 ` Matthew Wilcox
2018-10-03 14:05 ` Dave Hansen
2018-10-03 14:05 ` Dave Hansen
2018-10-03 16:07 ` Yu-cheng Yu
2018-10-03 16:07 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 10/27] drm/i915/gvt: Update _PAGE_DIRTY to _PAGE_DIRTY_BITS Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-10-03 13:19 ` Eugene Syromiatnikov
2018-10-03 13:19 ` Eugene Syromiatnikov
2018-09-21 15:03 ` [RFC PATCH v4 11/27] x86/mm: Introduce _PAGE_DIRTY_SW Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 12/27] x86/mm: Modify ptep_set_wrprotect and pmdp_set_wrprotect for _PAGE_DIRTY_SW Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 13/27] x86/mm: Shadow stack page fault error checking Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 14/27] mm: Handle shadow stack page fault Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 15/27] mm: Handle THP/HugeTLB " Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 16/27] mm: Update can_follow_write_pte/pmd for shadow stack Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 17/27] mm: Introduce do_mmap_locked() Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 18/27] x86/cet/shstk: User-mode shadow stack support Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-10-03 15:08 ` Eugene Syromiatnikov
2018-10-03 15:08 ` Eugene Syromiatnikov
2018-10-03 15:12 ` Yu-cheng Yu
2018-10-03 15:12 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 19/27] x86/cet/shstk: Introduce WRUSS instruction Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-10-03 4:15 ` Eugene Syromiatnikov
2018-10-03 4:15 ` Eugene Syromiatnikov
2018-09-21 15:03 ` [RFC PATCH v4 20/27] x86/cet/shstk: Signal handling for shadow stack Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-10-03 14:36 ` Eugene Syromiatnikov
2018-10-03 14:36 ` Eugene Syromiatnikov
2018-10-03 16:46 ` Jann Horn
2018-10-03 16:46 ` Jann Horn
2018-09-21 15:03 ` [RFC PATCH v4 21/27] x86/cet/shstk: ELF header parsing of Shadow Stack Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-10-03 23:27 ` Eugene Syromiatnikov
2018-10-03 23:27 ` Eugene Syromiatnikov
2018-10-09 21:15 ` Yu-cheng Yu
2018-10-09 21:15 ` Yu-cheng Yu
2018-10-15 23:40 ` Kees Cook
2018-10-15 23:40 ` Kees Cook
2018-10-16 17:23 ` Yu-cheng Yu
2018-10-16 17:23 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 22/27] x86/cet/shstk: Handle thread shadow stack Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 23/27] mm/map: Add Shadow stack pages to memory accounting Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 16:55 ` Randy Dunlap
2018-09-21 16:55 ` Randy Dunlap
2018-09-21 17:21 ` Yu-cheng Yu
2018-09-21 17:21 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 24/27] mm/mmap: Create a guard area between VMAs Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-10-03 4:56 ` Eugene Syromiatnikov
2018-10-03 4:56 ` Eugene Syromiatnikov
2018-10-03 5:36 ` Andy Lutomirski
2018-10-03 5:36 ` Andy Lutomirski
2018-10-03 16:00 ` Yu-cheng Yu
2018-10-03 16:00 ` Yu-cheng Yu
2018-10-03 16:18 ` Andy Lutomirski
2018-10-03 16:18 ` Andy Lutomirski
2018-10-03 16:32 ` Eugene Syromiatnikov
2018-10-03 16:32 ` Eugene Syromiatnikov
2018-10-03 16:40 ` Yu-cheng Yu [this message]
2018-10-03 16:40 ` Yu-cheng Yu
2018-10-03 16:52 ` Jann Horn
2018-10-03 16:52 ` Jann Horn
2018-10-03 21:21 ` Eugene Syromiatnikov
2018-10-03 21:21 ` Eugene Syromiatnikov
2018-09-21 15:03 ` [RFC PATCH v4 25/27] mm/mmap: Prevent Shadow Stack VMA merges Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 15:03 ` [RFC PATCH v4 26/27] x86/cet/shstk: Add arch_prctl functions for Shadow Stack Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-10-03 17:57 ` Eugene Syromiatnikov
2018-10-03 17:57 ` Eugene Syromiatnikov
2018-09-21 15:03 ` [RFC PATCH v4 27/27] x86/cet/shstk: Add Shadow Stack instructions to opcode map Yu-cheng Yu
2018-09-21 15:03 ` Yu-cheng Yu
2018-09-21 22:53 ` [RFC PATCH v4 00/27] Control Flow Enforcement: Shadow Stack Dave Hansen
2018-09-21 22:53 ` Dave Hansen
2018-09-24 15:25 ` Yu-cheng Yu
2018-09-24 15:25 ` Yu-cheng Yu
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