From: Eric Wong <redmine@...>
Date: 2011-01-29T03:02:26+09:00
Subject: [ruby-core:34944] [Ruby 1.8-Bug#4338][Open] random number generator not reseeded after fork in 1.8

Bug #4338: random number generator not reseeded after fork in 1.8
http://redmine.ruby-lang.org/issues/show/4338

Author: Eric Wong
Status: Open, Priority: Normal
Category: core, Target version: Ruby 1.8.7
ruby -v: ruby 1.8.7 (2010-12-23 patchlevel 330) [x86_64-linux]

rand should return different values in forked processes like in 1.9.2.  This
may have security implications for some programs.

Remembering to call srand after forking will fix the issue, but remembering is
hard especially since 1.9.2 makes it easy :)

The following example prints out 3 identical lines in 1.8.7:

  fork { $stdout.syswrite("#{rand}\n") }
  fork { $stdout.syswrite("#{rand}\n") }
  $stdout.syswrite("#{rand}\n")
  Process.waitall


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