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From: "fweimer at redhat dot com" <sourceware-bugzilla@sourceware.org>
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Subject: [Bug libc/29437] arc4random is too slow
Date: Mon, 08 Aug 2022 12:35:11 +0000
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https://sourceware.org/bugzilla/show_bug.cgi?id=3D29437

--- Comment #7 from Florian Weimer <fweimer at redhat dot com> ---
(In reply to Adhemerval Zanella from comment #6)
> For example, when a virtual machine is forked, restored, or duplicated, i=
t's
> imperative that the RNG doesn't generate the same outputs. For this reaso=
n,
> there's a small protocol between hypervisors and the kernel that indicates
> this has happened, alongside some ID, which the RNG uses to reseed
> immediately, so as not to return the same numbers.

Except that this doesn't work because if the suspend/resume happens a little
bit later, the unprotected application buffer to which the random data has =
been
written is restore multiple times. So clearly the actual rules around this =
are
different and much more complicated.

--=20
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