linux-kernel - Re: [tip:x86/mm] x86: Fix mmap random address range

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] [day] [month] [year] [list]

Message-ID: <16078.1323260954@turing-police.cc.vt.edu>
Date:	Wed, 07 Dec 2011 07:29:14 -0500
From:	Valdis.Kletnieks@...edu
To:	mingo@...hat.com, hpa@...or.com, linux-kernel@...r.kernel.org,
	torvalds@...ux-foundation.org, akpm@...ux-foundation.org,
	tglx@...utronix.de, ludwig.nussel@...e.de,
	harvey.harrison@...il.com, mingo@...e.hu
Cc:	linux-tip-commits@...r.kernel.org
Subject: Re: [tip:x86/mm] x86: Fix mmap random address range

On Mon, 05 Dec 2011 09:52:17 PST, tip-bot for Ludwig Nussel said:
> Commit-ID:  9af0c7a6fa860698d080481f24a342ba74b68982
> Gitweb:     http://git.kernel.org/tip/9af0c7a6fa860698d080481f24a342ba74b68982
> Author:     Ludwig Nussel <ludwig.nussel@...e.de>
> AuthorDate: Tue, 15 Nov 2011 14:46:46 -0800
> Committer:  Ingo Molnar <mingo@...e.hu>
> CommitDate: Mon, 5 Dec 2011 17:07:23 +0100
>
> x86: Fix mmap random address range
>
> On x86_32 casting the unsigned int result of get_random_int() to
> long may result in a negative value.  On x86_32 the range of
> mmap_rnd() therefore was -255 to 255.  The 32bit mode on x86_64
> used 0 to 255 as intended.

Will somebody please hand me a big dose of caffeine and explain to me
how the range could have been -255 to 255?  -256 maybe, or -128 to 127,
but -255??!?

Content of type "application/pgp-signature" skipped