linux-kernel - Re: [PATCH 2/2] random: Account for entropy loss due to overwrites

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: <CA+55aFwkEMAkvZFdeQm2PKQD1xgFBfVa+kTwJXGmWXoDqDp7xQ@mail.gmail.com>
Date:	Thu, 25 Apr 2013 07:38:23 -0700
From:	Linus Torvalds <torvalds@...ux-foundation.org>
To:	"H. Peter Anvin" <hpa@...or.com>
Cc:	"Ted Ts'o" <tytso@....edu>, DJ Johnston <dj.johnston@...el.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	"H. Peter Anvin" <hpa@...ux.intel.com>,
	stable <stable@...r.kernel.org>
Subject: Re: [PATCH 2/2] random: Account for entropy loss due to overwrites

This doesn't work AT ALL. You even hint at the reason why in your message.

On Tue, Apr 23, 2013 at 9:26 PM, H. Peter Anvin <hpa@...or.com> wrote:
>
> As such, this conservatism seems more than justified.  Note, however,
> that attempting to add one bit of entropy will never succeed; nor will
> two bits unless the pool is completely empty.  These roundoff
> artifacts could be improved by using fixed-point arithmetic and adding
> some number of fractional entropy bits.

Take a look at "add_interrupt_randomness()". Hmm..

                Linus
--
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/