[tor-bugs] #26040 [Core Tor/Tor]: Improve getrandom handling

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#26040: Improve getrandom handling
--------------------------+------------------------------------
 Reporter:  Hello71       |          Owner:  Hello71
     Type:  enhancement   |         Status:  needs_revision
 Priority:  Medium        |      Milestone:  Tor: 0.3.4.x-final
Component:  Core Tor/Tor  |        Version:
 Severity:  Normal        |     Resolution:
 Keywords:                |  Actual Points:
Parent ID:                |         Points:
 Reviewer:  catalyst      |        Sponsor:
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Changes (by catalyst):

 * status:  needs_review => needs_revision


Comment:

 Thanks for the patch!  The `getrandom(2)` manpage on one of my Ubuntu VMs
 says
 {{{
        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.
 }}}
 so in the case of tor starting up soon after boot, I think it might be
 possible to get `EINTR` if tor receives a signal while blocked on
 insufficient entropy.  Arguably we want to retry in this case.  (Also I
 would be interested in hearing if there are good reasons to treat this as
 a bug when it occurs anyway.)

 Please make a GitHub pull request for your revised patches so CI can run
 on them.  Thanks!

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/26040#comment:4>
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