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Bug#336220: marked as done (xdm: bogus /dev/mem access lead to trouble on arm platforms)

Your message dated Sat, 6 Mar 2010 17:09:46 +0100
with message-id <20100306160946.GA7379@loulous.org>
and subject line Re: Bug#336220: xdm: bogus /dev/mem access lead to trouble on arm platforms
has caused the Debian Bug report #336220,
regarding xdm: bogus /dev/mem access lead to trouble on arm platforms
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.

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-- 
336220: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=336220
Debian Bug Tracking System
Contact owner@bugs.debian.org with problems
--- Begin Message --- 
Package: xdm
Severity: important

On arm platforms where physical RAM doesn't start at physical address
zero, opening /dev/mem and reading from it causes a kernel oops.  This
is arguably a kernel bug, but it's still not a very good idea to just
start randomly poking around in /dev/mem in search of entropy, which is
what xdm does if it can't get entropy elsewhere.

(When the kernel is fixed, blindly reading from /dev/mem will simply
just fail with EFAULT instead of oopsing.  If that will cause xdm to
fail, it should really just fail right away if /dev/random doesn't work.)


-- System Information:
Debian Release: testing/unstable
  APT prefers stable
  APT policy: (500, 'stable')
Architecture: armeb (armv4b)
Shell:  /bin/sh linked to /bin/bash
Kernel: Linux 2.6.13
Locale: LANG=C, LC_CTYPE=C (charmap=ANSI_X3.4-1968)

--- End Message ---
--- Begin Message --- 
On Mon, Sep 17, 2007 at 07:54:12PM +0200, Brice Goglin wrote:
> Lennert Buytenhek wrote:
> > The problem is not that xdm doesn't check /dev/urandom first, the
> > problem is that it reads from /dev/mem _at all_.
> >
> > It is possible that checking /dev/urandom first masks the problem
> > in most configurations, but it doesn't solve it (if you don't have
> > /dev/random and /dev/urandom in your filesystem for whatever reason,
> > you still oops.)
> >   
> 
> 
> Right, but still, having a workaround when /dev/urandom exists is much
> better than having xdm broken on all arm. So, do you know if
> /dev/urandom is more often (always?) available on arm than /dev/random?
> What about the machine where you had the original bug?

No reply in 2 years and a half, closing.

Brice

--- End Message ---
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