[asterisk-bugs] [Asterisk 0012453]: British Telecom line testing causes segfault on chan_zap.c

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=12453 
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Reported By:                Alex728
Assigned To:                
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Project:                    Asterisk
Issue ID:                   12453
Category:                   Channels/chan_zap
Reproducibility:            always
Severity:                   crash
Priority:                   normal
Status:                     new
Asterisk Version:           1.4.19 
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:             04-15-2008 19:39 CDT
Last Modified:              04-15-2008 19:53 CDT
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Summary:                    British Telecom line testing causes segfault on
chan_zap.c
Description: 
Telephone lines in the UK are subjected to various automatic line tests in
the evening. These include a polarity reversal, and alternate application
of earth and battery (-48V) to the A and B wires (Tip and ring) 

Since version 1.4.18 of Asterisk, these conditions are detected first as a
spurious zaptel alarm, then a polarity reversal before caller ID. For some
reason this causes chan_zap.c to crash with a segmentation fault.

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---------------------------------------------------------------------- 
 Alex728 - 04-15-08 19:53  
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attached 

coredump-info.txt : gdb details of the core dump
bt-full.txt : gdb backtrace
asterisk-log.txt : asterisk log showing chan_zap.c response to these
signals
351v4p5.pdf : British Telecommunications Suppliers Information Note - page
14 onwards describes the nature of the line testing signals. 

Issue History 
Date Modified   Username       Field                    Change               
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04-15-08 19:53  Alex728        Note Added: 0085530                          
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