[asterisk-bugs] [Asterisk 0013116]: Asterisk 1.4.21.1 segfaults many times daily using mixmonitor

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=13116 
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Reported By:                aragon
Assigned To:                
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Project:                    Asterisk
Issue ID:                   13116
Category:                   Applications/app_mixmonitor
Reproducibility:            always
Severity:                   crash
Priority:                   normal
Status:                     feedback
Asterisk Version:           1.4.21 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             2008-07-20 14:37 CDT
Last Modified:              2008-12-02 13:35 CST
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Summary:                    Asterisk 1.4.21.1 segfaults many times daily using
mixmonitor
Description: 
Random crashes while mixmonitor is used
backtrace attached
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Relationships       ID      Summary
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has duplicate       0013210 Asterisk production environment crashes...
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 (0095682) putnopvut (administrator) - 2008-12-02 13:35
 http://bugs.digium.com/view.php?id=13116#c95682 
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I started wondering how a frame that claims to have 160 samples but has
NULL data and a 0 datalen could get in the queue of frames used by
MixMonitor. I couldn't reproduce the problem here, but I did find in the
jitter buffer code that if a jitter buffer implementation tells the core to
interpolate a frame, then a frame will be created with a NULL data pointer,
a datalen of 0, but will have its samples set to 160 (240 if iLBC is used).
Such interpolated frames seem to be sort of "placeholders" for when the
jitter buffer cannot give an actual frame of voice. Such frames appear to
be legitimate and have their uses. So I think an appropriate fix is to make
sure that before giving a frame off to the MixMonitor's queue of frames,
check to make sure that it has data in it first. I'll write a patch for
this which you can test. 

Issue History 
Date Modified    Username       Field                    Change               
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2008-12-02 13:35 putnopvut      Note Added: 0095682                          
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