linux-kernel - Re: [PATCH v3 21/36] arm64/mm: Implement map_shadow

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 for Android: free password hash cracker in your pocket

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

Message-ID: <0a6c90d6-f790-4036-a364-d4761fdd0e95@sirena.org.uk>
Date:   Mon, 31 Jul 2023 18:06:28 +0100
From:   Mark Brown <broonie@...nel.org>
To:     "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
Cc:     "corbet@....net" <corbet@....net>,
        "ardb@...nel.org" <ardb@...nel.org>,
        "maz@...nel.org" <maz@...nel.org>,
        "shuah@...nel.org" <shuah@...nel.org>,
        "Szabolcs.Nagy@....com" <Szabolcs.Nagy@....com>,
        "keescook@...omium.org" <keescook@...omium.org>,
        "james.morse@....com" <james.morse@....com>,
        "debug@...osinc.com" <debug@...osinc.com>,
        "akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
        "catalin.marinas@....com" <catalin.marinas@....com>,
        "oleg@...hat.com" <oleg@...hat.com>,
        "arnd@...db.de" <arnd@...db.de>,
        "ebiederm@...ssion.com" <ebiederm@...ssion.com>,
        "will@...nel.org" <will@...nel.org>,
        "suzuki.poulose@....com" <suzuki.poulose@....com>,
        "oliver.upton@...ux.dev" <oliver.upton@...ux.dev>,
        "hjl.tools@...il.com" <hjl.tools@...il.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux-riscv@...ts.infradead.org" <linux-riscv@...ts.infradead.org>,
        "linux-kselftest@...r.kernel.org" <linux-kselftest@...r.kernel.org>,
        "linux-fsdevel@...r.kernel.org" <linux-fsdevel@...r.kernel.org>,
        "linux-mm@...ck.org" <linux-mm@...ck.org>,
        "paul.walmsley@...ive.com" <paul.walmsley@...ive.com>,
        "aou@...s.berkeley.edu" <aou@...s.berkeley.edu>,
        "palmer@...belt.com" <palmer@...belt.com>,
        "linux-doc@...r.kernel.org" <linux-doc@...r.kernel.org>,
        "kvmarm@...ts.linux.dev" <kvmarm@...ts.linux.dev>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        "linux-arch@...r.kernel.org" <linux-arch@...r.kernel.org>
Subject: Re: [PATCH v3 21/36] arm64/mm: Implement map_shadow_stack()

On Mon, Jul 31, 2023 at 03:56:50PM +0000, Edgecombe, Rick P wrote:
> On Mon, 2023-07-31 at 14:43 +0100, Mark Brown wrote:

> Any thoughts on the questions at the end of this mail?

> https://lore.kernel.org/lkml/7a4c97f68347d4188286c543cdccaa12577cdb9e.camel@intel.com/

Those are:

> Someday when the x86 side is finally upstream I have a manpage for
> map_shadow_stack. Any differences on the arm side would need to be
> documented, but I'm not sure why there should be any differences. Like,
> why not use the same flags? Or have a new flag for token+end marker
> that x86 can use as well?

Ah, it wasn't clear to me that this was a question rather than just
open decisions about the eventual manpage.  Looking again I think what
you're asking about is that I see that at some point in development I
lost the SHADOW_STACK_SET_TOKEN flag which x86 has.  I suspect that was
a rebasing issue as it wasn't a deliberate decision, there's no reason
we couldn't have that.  Other than that and the fact that we add both a
stack swap token and a top of stack marker I'm not aware of any
differences.

Download attachment "signature.asc" of type "application/pgp-signature" (489 bytes)