linux-kernel - Re: [PATCH v7 22/41] mm/mmap: Add shadow stack pages to memory accounting

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <acdfaf37e2afc0616c394fb979f117d0102519d1.camel@intel.com>
Date:   Mon, 6 Mar 2023 18:11:32 +0000
From:   "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
To:     "bp@...en8.de" <bp@...en8.de>
CC:     "david@...hat.com" <david@...hat.com>,
        "bsingharora@...il.com" <bsingharora@...il.com>,
        "hpa@...or.com" <hpa@...or.com>,
        "Syromiatnikov, Eugene" <esyr@...hat.com>,
        "peterz@...radead.org" <peterz@...radead.org>,
        "rdunlap@...radead.org" <rdunlap@...radead.org>,
        "keescook@...omium.org" <keescook@...omium.org>,
        "Yu, Yu-cheng" <yu-cheng.yu@...el.com>,
        "dave.hansen@...ux.intel.com" <dave.hansen@...ux.intel.com>,
        "kirill.shutemov@...ux.intel.com" <kirill.shutemov@...ux.intel.com>,
        "Eranian, Stephane" <eranian@...gle.com>,
        "linux-mm@...ck.org" <linux-mm@...ck.org>,
        "fweimer@...hat.com" <fweimer@...hat.com>,
        "nadav.amit@...il.com" <nadav.amit@...il.com>,
        "jannh@...gle.com" <jannh@...gle.com>,
        "dethoma@...rosoft.com" <dethoma@...rosoft.com>,
        "kcc@...gle.com" <kcc@...gle.com>,
        "linux-arch@...r.kernel.org" <linux-arch@...r.kernel.org>,
        "pavel@....cz" <pavel@....cz>, "oleg@...hat.com" <oleg@...hat.com>,
        "hjl.tools@...il.com" <hjl.tools@...il.com>,
        "Yang, Weijiang" <weijiang.yang@...el.com>,
        "Lutomirski, Andy" <luto@...nel.org>,
        "linux-doc@...r.kernel.org" <linux-doc@...r.kernel.org>,
        "arnd@...db.de" <arnd@...db.de>,
        "tglx@...utronix.de" <tglx@...utronix.de>,
        "Schimpe, Christina" <christina.schimpe@...el.com>,
        "mike.kravetz@...cle.com" <mike.kravetz@...cle.com>,
        "x86@...nel.org" <x86@...nel.org>,
        "akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
        "debug@...osinc.com" <debug@...osinc.com>,
        "jamorris@...ux.microsoft.com" <jamorris@...ux.microsoft.com>,
        "john.allen@....com" <john.allen@....com>,
        "rppt@...nel.org" <rppt@...nel.org>,
        "andrew.cooper3@...rix.com" <andrew.cooper3@...rix.com>,
        "mingo@...hat.com" <mingo@...hat.com>,
        "corbet@....net" <corbet@....net>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux-api@...r.kernel.org" <linux-api@...r.kernel.org>,
        "gorcunov@...il.com" <gorcunov@...il.com>
Subject: Re: [PATCH v7 22/41] mm/mmap: Add shadow stack pages to memory
 accounting

On Mon, 2023-03-06 at 14:01 +0100, Borislav Petkov wrote:
> On Mon, Feb 27, 2023 at 02:29:38PM -0800, Rick Edgecombe wrote:
> > From: Yu-cheng Yu <yu-cheng.yu@...el.com>
> > 
> > The x86 Control-flow Enforcement Technology (CET) feature includes
> > a new
> > type of memory called shadow stack. This shadow stack memory has
> > some
> > unusual properties, which requires some core mm changes to function
> > properly.
> > 
> > Account shadow stack pages to stack memory. Do this by adding a
> > VM_SHADOW_STACK check in is_stack_mapping().
> 
> That last sentence is superfluous.

Before this version it was open coded, but David Hildenbrand suggested
this is_stack_mapping() solution. Should it be explained more, or just
dropped?