linux-kernel - Re: [PATCH v7 33/41] x86/shstk: Introduce 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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <b85a86e8013280ce17a54d570aa162f1d463a230.camel@intel.com>
Date:   Fri, 10 Mar 2023 17:12:40 +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>,
        "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 33/41] x86/shstk: Introduce map_shadow_stack syscall

On Fri, 2023-03-10 at 17:11 +0100, Borislav Petkov wrote:

[...]

Thanks on all the text edits.

> On Mon, Feb 27, 2023 at 02:29:49PM -0800, Rick Edgecombe wrote:
> > diff --git a/arch/x86/entry/syscalls/syscall_64.tbl
> > b/arch/x86/entry/syscalls/syscall_64.tbl
> > index c84d12608cd2..f65c671ce3b1 100644
> > --- a/arch/x86/entry/syscalls/syscall_64.tbl
> > +++ b/arch/x86/entry/syscalls/syscall_64.tbl
> > @@ -372,6 +372,7 @@
> >  448	common	process_mrelease	sys_process_mreleas
> > e
> >  449	common	futex_waitv		sys_futex_waitv
> >  450	common	set_mempolicy_home_node	sys_set_mempolicy_h
> > ome_node
> > +451	64	map_shadow_stack	sys_map_shadow_stack
> 
> Yeah, this'll need a manpage too, I presume. But later.

I have one to submit.

[...]

> > +
> > +	if (addr && addr <= 0xFFFFFFFF)
> 
> 			< SZ_4G
> 
> > +		return -EINVAL;
> 
> Can we use distinct negative retvals in each case so that it is clear
> to
> userspace where it fails, *if* it fails?

Good idea, I think maybe ERANGE.