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Date: Mon, 6 Oct 2008 22:30:14 +0400
From: Andrey Chernov <ache@nagual.pp.ru>
To: Tim Kientzle <kientzle@freebsd.org>
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User-Agent: Mutt/1.5.18 (2008-05-17)
Cc: freebsd-current@freebsd.org
Subject: Re: firefox3-bin crashes near arc4random_buf()
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On Sun, Oct 05, 2008 at 05:34:22PM -0700, Tim Kientzle wrote:
> Something is still screwy about the backtrace.  dbopen()
> doesn't call arc4random_buf.  However, it does call
> mkstemp() which does call arc4random_uniform, which should
> be right next to arc4random_buf in memory.  GCC optimizations
> could be obscuring the call stack here.

FYI arc4random_uniform() just do some internal calculations then call 
arc4random() (perhaps several times) which have threaded lock, like any 
other arc4random* family. Like you can see, calculation not involves 
division, so division by zero can't happen and upper_bound passed by 
mkstemp() is very reasonable small number. Calling arc4random_buf() is not 
possible in this path.

-- 
http://ache.pp.ru/