[asterisk-bugs] [Asterisk 0013035]: ChanSpy multiple channels attached to one

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=13035 
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Reported By:                bfsworks
Assigned To:                
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Project:                    Asterisk
Issue ID:                   13035
Category:                   Applications/app_chanspy
Reproducibility:            always
Severity:                   crash
Priority:                   normal
Status:                     feedback
Asterisk Version:           1.4.21 
SVN Branch (only for SVN checkouts, not tarball releases):  1.4  
SVN Revision (number only!): 128029 
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             2008-07-09 08:38 CDT
Last Modified:              2008-12-10 12:57 CST
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Summary:                    ChanSpy multiple channels attached to one
Description: 
Chanspy seems to be crashing when multiple sip channels are reading from
the same channel(s). For example in a call center environment if trainee 1
and trainee 2 dial an extension that runs chanspy and they happen spy on
the same sip conversation then a segfault will occur. This is only
reproducible if multiple sip reads occur on a channel.
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Relationships       ID      Summary
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has duplicate       0013682 Segmentation Fault with 1.4.21.2 in rtp...
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 (0096128) putnopvut (administrator) - 2008-12-10 12:57
 http://bugs.digium.com/view.php?id=13035#c96128 
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So here's something I'd like to consider on this issue. I've noticed that
all the people who have provided a sample dialplan for their crash have
been using the 'g' option to ChanSpy. There was an issue which was fixed
with regards to this option where a stack overflow would occur eventually
due to a busy loop which kept allocating new stack data. This bug fix is
present in 1.4.22. I think that it may be that this is the same basic issue
which is causing this, but I have no way to be sure of it. The clues that
are tipping me off on this are that the crashes don't always appear to be
happening in the same place, they do not appear to have anything to do with
accessing freed or invalid memory, and they appear to happen in what would
otherwise seem to be uncrashable places. The problem with this idea is that
I can't really see any reason why having multiple people spying on a single
channel would cause the problem.

It would be really great if someone running 1.4.22 or one of the 1.4.23
release candidates could determine if this issue still occurs in those
versions. 

Issue History 
Date Modified    Username       Field                    Change               
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2008-12-10 12:57 putnopvut      Note Added: 0096128                          
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