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]

Message-ID: <54ADBEB1.7000902@linux.intel.com>
Date:	Wed, 07 Jan 2015 15:18:09 -0800
From:	Dave Hansen <dave.hansen@...ux.intel.com>
To:	Andy Lutomirski <luto@...capital.net>
CC:	Andi Kleen <andi@...stfloor.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	X86 ML <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 03:04 PM, Andy Lutomirski wrote:
> Anyway, if it's actually a problem to change it, I have no real
> problem keeping it, but I think we *really* need to validate the rest
> of the arguments at the very least.

If we "validate" the arguments like you suggested, then a call like this:

	prctl(PR_MPX_DISABLE_MANAGEMENT);

ends up returning -EINVAL:

> prctl(0x2b /* PR_??? */, 0x7fffffd3, 0x7f360955e9e0, 0x2c, 0x7f3609314840) = -1 EINVAL (Invalid argument)

A quick grep through ltp and some other source I have laying around does
*not* show folks adding 0's to these calls for "empty" arguments.  Is
this really something we want to do?

	prctl(PR_MPX_DISABLE_MANAGEMENT, 0, 0, 0, 0);
--
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/