[tor-bugs] #29527 [Core Tor/Tor]: Division by zero: undefined behaviour in circuitpadding/circuitpadding_sample_distribution test

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#29527: Division by zero: undefined behaviour in
circuitpadding/circuitpadding_sample_distribution test
-------------------------------------------------+-------------------------
 Reporter:  teor                                 |          Owner:  (none)
     Type:  defect                               |         Status:
                                                 |  needs_review
 Priority:  High                                 |      Milestone:  Tor:
                                                 |  0.4.0.x-final
Component:  Core Tor/Tor                         |        Version:
 Severity:  Normal                               |     Resolution:
 Keywords:  regression, tor-ci, tor-test,        |  Actual Points:
  040-must                                       |
Parent ID:                                       |         Points:
 Reviewer:                                       |        Sponsor:
-------------------------------------------------+-------------------------
Changes (by asn):

 * status:  new => needs_review


Comment:

 Thanks for the great analysis in this ticket. Based on the comments here
 it was quite easy to to write a patch.

 You can see it in https://github.com/torproject/tor/pull/722
 Please note that only the last two commits are about this ticket, the
 others are there because I based the branch on #29298 to avoid some
 conflicts in the future.

 The first commit (a64ccf151f) fixes the probability distribution
 parameters that Riastradh mentioned with bold in comment:7. The second
 commit (f708055e9f) silences float-divide-by-zero as suggested by #29528.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/29527#comment:11>
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