[asterisk-bugs] [Asterisk 0017059]: What causes 'Bad Magic Number'? As immediately after segfault.

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=17059 
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Reported By:                alecdavis
Assigned To:                
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Project:                    Asterisk
Issue ID:                   17059
Category:                   Core/PBX
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     new
Asterisk Version:           SVN 
JIRA:                        
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases):  trunk 
SVN Revision (number only!): 252241 
Request Review:              
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Date Submitted:             2010-03-19 03:15 CDT
Last Modified:              2010-03-19 03:20 CDT
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Summary:                    What causes 'Bad Magic Number'? As immediately after
segfault.
Description: 
One way to get a 'Bad Magic Number' is to loop the Local Channel a number
of times.

This is repeatable with following test dialplan.

When 10000 is dialled the local channel is looped 20 times, and would
immediately segfault after some 'Exceptionly long queued frames...

[phones]
exten => _10020,1,Answer()
exten => _10020,n,Playback(test-tones-follow)
exten => _10020,n,Milliwatt()

exten => _1XXXX,1,Set(i=${MATH(${EXTEN}+1,int)})
exten => _1XXXX,n,Dial(Local/${i}@phones,,r)

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Relationships       ID      Summary
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parent of           0017037 [patch] internal_ao2_ref fails to check...
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 (0119603) alecdavis (manager) - 2010-03-19 03:20
 https://issues.asterisk.org/view.php?id=17059#c119603 
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Maybe a clue below, just after a Local Channel in the loop was optimized
out, then Bad Magic Number, then segfault.

console output:

 == Spawn extension (phones, 10015, 2) exited non-zero on
'Local/10015 at phones-f860;2'
[Mar 16 23:14:00] ERROR[30417]: astobj2.c:116 INTERNAL_OBJ: bad magic
number 0x0 for 0x85dc240 

Issue History 
Date Modified    Username       Field                    Change               
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2010-03-19 03:20 alecdavis      Note Added: 0119603                          
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