Re: Why does reading from /dev/urandom deplete entropy so much?

Matt Mackall wrote:
On Tue, Dec 04, 2007 at 04:23:12PM -0600, Mike McGrath wrote:
Matt Mackall wrote:
On Tue, Dec 04, 2007 at 03:18:27PM -0600, Mike McGrath wrote:
Matt Mackall wrote:
which would have been in v2.6.22-rc4 through the normal CVE process.
The only other bits in there are wall time and utsname, so systems
with no CMOS clock would behave repeatably. Can we find out what
kernels are affected?


We can but it will likely take a few weeks to get a good sampling. UUID is unique in the db so when someone checks in with the same UUID, the old one gets overwritten.
We can probably assume that for whatever reason the two things with
duplicate UUID had the same seed. If not, we've got -much- bigger
problems.
Ok, I think I see whats going on here. I have some further investigation to do but it seems that the way our Live CD installer works is causing these issues. I'm going to try to grab some live CD's and hardware to confirm but at this point it seems thats whats going on.

Alright, keep me posted. We probably need a scheme to make the initial
seed more robust regardless of what you find out

Ok, whats going on here is an issue with how the smolt RPM installs the UUID and how Fedora's Live CD does an install. It's a complete false alarm on the kernel side, sorry for the confusion.

-Mike

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