[LEDE-DEV] [PATCH v5] base-files: seed /dev/urandom

[Etienne Champetier]

2016-07-19 7:40 GMT+02:00 Etienne Champetier <champetier.etienne at gmail.com>:
> 2016-07-19 7:09 GMT+02:00 Jo-Philipp Wich <jo at mein.io>:
>> Hi Daniel,
>>
>> interesting failure mode ;(
>>
>> To me it seems the easiest fix is changing the getrandom syscall wrapper
>> utility to use the GRND_NONBLOCK flag in order to be interruptible by
>> signals.
>>
>> Thoughts?
>
> According to the man page it's already interruptible if /dev/urandom
> init is not done
> http://man7.org/linux/man-pages/man2/getrandom.2.html
>
> The behavior when a call to getrandom() that is blocked while reading
> from /dev/urandom is interrupted by a signal handler depends on the
> initialization state of the entropy buffer and on the request size,
> buflen.  If the entropy is not yet initialized, then the call will
> fail with the EINTR error.
>
> and getrandom handle syscall errors
> https://git.lede-project.org/?p=project/ubox.git;a=blob;f=getrandom.c;h=96712028589b100f3fab845f92d7fd554428efe4;hb=HEAD
>
> quick fix before I understand the problem is to add
> getrandom 1 > /dev/null
>

p.s: I'll try to work on this today or tomorrow

>
>
>>
>> ~ Jo
>>