[asterisk-bugs] [Zaptel 0010806]: Channel opening and unregistering race

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=10806 
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Reported By:                Matti
Assigned To:                
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Project:                    Zaptel
Issue ID:                   10806
Category:                   zaptel (the module)
Reproducibility:            sometimes
Severity:                   crash
Priority:                   normal
Status:                     new
Zaptel Version:              SVN 
SVN Branch (only for SVN checkouts, not tarball releases):  1.4  
SVN Revision (number only!): 3052 
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             09-23-2007 03:45 CDT
Last Modified:              09-29-2007 06:06 CDT
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Summary:                    Channel opening and unregistering race
Description: 
Function zt_specchan_open can have a race condition with zt_chan_unreg
resulting in crashing of the program (Asterisk) or the whole computer
during the opening of a Zap device file.
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---------------------------------------------------------------------- 
 tzafrir - 09-29-07 06:06  
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Your suggested solution is to replace the channel lock with a semaphore.
Could you please explain the reason for that?

Some smaller points:

1. I do agree with you that no pint for free_tone_zone to re-check the
validity of the data.

2. I don't understand why you need to get a channels lock just for
checking if !spans[j] in VALID_SPAN() . 

Issue History 
Date Modified   Username       Field                    Change               
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09-29-07 06:06  tzafrir        Note Added: 0071203                          
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