[Asterisk-bugs] [Asterisk 0010227]: Incorrect handling of VNAK retransmission

[noreply at bugs.digium.com]

The following issue has been RESOLVED. 
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http://bugs.digium.com/view.php?id=10227 
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Reported By:                mihai
Assigned To:                russell
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Project:                    Asterisk
Issue ID:                   10227
Category:                   Channels/chan_iax2
Reproducibility:            random
Severity:                   minor
Priority:                   normal
Status:                     resolved
Asterisk Version:           1.4.7.1  
SVN Branch (only for SVN checkouts, not tarball releases): N/A  
SVN Revision (number only!):  
Disclaimer on File?:        Yes 
Request Review:              
Resolution:                 fixed
Fixed in Version:           
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Date Submitted:             07-18-2007 09:49 CDT
Last Modified:              07-18-2007 16:06 CDT
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Summary:                    Incorrect handling of VNAK retransmission
Description: 
In vnak_retransmit you can find the following code:

if ((f->callno == callno) && iaxs[f->callno] &&
	(f->oseqno >= last)) {
	send_packet(f);

oseqno and last are 8-bit values that wrap around, so if a VNAK
retransmission is requested right after a wraparound, this code will behave
incorrectly. 

Most probable effect would be that asterisk would not retransmitting the
right frames and the other endpoint would keep asking for them, generating
a VNAK storm
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---------------------------------------------------------------------- 
 russell - 07-18-07 16:06  
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I'm going to mark this one as fixed for now as the specific issue here is
resolved.  But please let me know if you still have a problem after using
this change.  I have a bad feeling that it's not all fixed, but we will
see. 

Issue History 
Date Modified   Username       Field                    Change               
====================================================================== 
07-18-07 16:06  russell        Status                   assigned => resolved
07-18-07 16:06  russell        Resolution               open => fixed       
07-18-07 16:06  russell        Note Added: 0067553                          
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