linux-kernel - Re: [PATCH 3.19 3/3] x86, mpx: Change the MPX enable/disable API to arch

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]

Date:	Mon, 05 Jan 2015 13:18:27 -0800
From:	Dave Hansen <dave.hansen@...ux.intel.com>
To:	Andi Kleen <andi@...stfloor.org>
CC:	Andy Lutomirski <luto@...capital.net>,
	linux-kernel@...r.kernel.org, x86@...nel.org,
	Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH 3.19 3/3] x86, mpx: Change the MPX enable/disable API
 to arch_prctl

On 01/05/2015 12:42 PM, Andi Kleen wrote:
> Dave Hansen <dave.hansen@...ux.intel.com> writes:
>> On 12/29/2014 04:52 PM, Andy Lutomirski wrote:
>>> This has the benefit the it avoids cluttering prctl with more
>>> arch-specific functionality.  The down side is that arch_prctl will
>>> need to be wired up as a 32-bit syscall to add 32-bit support for
>>> MPX.
>>
>> There is existing userspace out there which depends on the existing
>> prctl() setup.  There isn't a _lot_ and it might still be able to be
>> changed easily, but this isn't a given.
>>
>> I'll check in with the folks doing the gcc (runtime) part of this next
>> week and see what they think.
> 
> It'll be quite messy for 32bit because they would need to use syscall(),
> as glibc won't have a arch_prctl stub.

Yeah, I'd _really_ prefer not to change it.  The code is in a gcc
branch, but is getting pulled in to the 5.0 release.  We've got
*absolutely* no shortage of prctl numbers.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/