Re: [PATCH] Re: [PATCH] drivers/net: remove network drivers' last few uses of IRQF_SAMPLE_RANDOM

[Adrian Bunk <bunk@kernel.org>]

On Fri, May 16, 2008 at 12:19:49PM +0200, Andi Kleen wrote:
>...
> The only problem you got from possible bogus input is that the entropy
> counts will be wrong, but in my experience nearly all programs
> use /dev/urandom anyways because /dev/random is just a DoS waiting
> to happen and user space programmers know that.
>...

If programs just need some random data without relying on the fact that 
it's cryptographically strong /dev/urandom is the right choice.

But some programs need entropy for doing crypto stuff, and a local DoS 
is harmless compared to the consequences of bad /dev/random data.

Consider as a worst case the just discovered OpenSSL bug in Debian where 
all accounts with public key authentification and keys created on a 
Debian/Ubuntu system during the last 20 months [1] can be taken over by 
an attacker within less than 20 minutes with a simple brute force 
attack. [2]

> -Andi

cu
Adrian

[1] 13 months for Debian stable users
[2] http://www.derkeiler.com/Mailing-Lists/Full-Disclosure/2008-05/msg00416.html

-- 

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       "Only a promise," Lao Er said.
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