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Bug 120914

Summary:	xdm should use /dev/urandom [xdm error: Cannot read randomFile "/dev/mem"; X cookies may be easily guessable]
Product:	[Fedora] Fedora	Reporter:	Aleksey Nogin <aleksey>
Component:	xorg-x11	Assignee:	Mike A. Harris <mharris>
Status:	CLOSED RAWHIDE	QA Contact:	David Lawrence <dkl>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	rawhide	CC:	jdennis, russell, wtogami
Target Milestone:	---	Keywords:	Security, SELinux
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2004-09-01 11:37:13 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Aleksey Nogin 2004-04-15 07:08:11 UTC

Currently xdm attempts to use /dev/mem as a source of randomness for
cookie generation. This is a bad idea in any case, but when SELinux is
in enforcing mode, this is especially bad since SELinux prohibits this
and, as xdm-errors log file states, "X cookies may be easily guessable".

The similar bug exists for kdm as well (bug 118051) and it looks that
kdm just borrowed code from xdm. I have investigated the kdm case a
bit more, see details in bug 118051.

Comment 1 Aleksey Nogin 2004-05-06 07:00:31 UTC

RYI: the kdm version of this bug - bug 118051 - was fixed a few days ago.

Comment 2 Warren Togami 2004-05-06 07:08:23 UTC

I suspect this is more about avoiding another X rebuild, because it is
very large.  This does not seem to be a very serious problem because
nobody would prefer to use xdm over gdm/kdm, but I could be assuming
too much of course...

Comment 3 Søren Sandmann Pedersen 2004-07-20 17:49:18 UTC

Fixed upstream.

Comment 4 Mike A. Harris 2004-09-01 11:37:13 UTC

Upstream X.Org is in our fedora devel builds, changing status to
"RAWHIDE".