linux-kernel - [PATCH v2 0/2] 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 for Android: free password hash cracker in your pocket

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

Message-Id: <1353482868-8064-1-git-send-email-hpa@linux.intel.com>
Date:	Tue, 20 Nov 2012 23:27:46 -0800
From:	"H. Peter Anvin" <hpa@...ux.intel.com>
To:	"Theodore Ts'o" <tytso@....edu>
Cc:	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	DJ Johnston <dj.johnston@...el.com>,
	"H. Peter Anvin" <hpa@...or.com>,
	"H. Peter Anvin" <hpa@...ux.intel.com>
Subject: [PATCH v2 0/2] random: Account for entropy loss due to overwrites

From: "H. Peter Anvin" <hpa@...ux.intel.com>

When we write entropy into a non-empty pool, we currently don't
account at all for the fact that we will probabilistically overwrite
some of the entropy in that pool.  This means that unless the pool is
fully empty, we are currently *guaranteed* to overestimate the amount
of entropy in the pool!

This version of the patchset avoids manually duplicating information
by using a macro.  This removes *all* dynamic computation of derived
pool information and replaces them with static information: on just
about every architecture accessing pointer+offset is no more expensive
than just plain pointer, and this lets us get the information we
actually need from the start.
--
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/