[asterisk-bugs] [Asterisk 0018658]: crash while looking up realtime presence hint

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=18658 
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Reported By:                byronclark
Assigned To:                
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Project:                    Asterisk
Issue ID:                   18658
Category:                   Channels/chan_sip/Subscriptions
Reproducibility:            always
Severity:                   crash
Priority:                   normal
Status:                     new
Asterisk Version:           1.6.2.16.1 
JIRA:                        
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2011-01-21 11:57 CST
Last Modified:              2011-01-21 11:59 CST
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Summary:                    crash while looking up realtime presence hint
Description: 
After upgrading from 1.6.2.11 to 1.6.2.16.1, I'm seeing a crash as soon as
the first Subscription request for presence arrives.

It appears the crash is caused by ast_autoservice_start being called on
the mostly empty channel created main/pbx.c:ast_add_extension2_lockopt():

	/* If we are adding a hint evalulate in variables and global variables
*/
	if (priority == PRIORITY_HINT && strstr(application, "${") &&
!strstr(extension, "_")) {
		struct ast_channel c = {0, };

		ast_copy_string(c.exten, extension, sizeof(c.exten));
		ast_copy_string(c.context, con->name, sizeof(c.context));
		pbx_substitute_variables_helper(&c, application, expand_buf,
sizeof(expand_buf));
		application = expand_buf;
	}


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---------------------------------------------------------------------- 
 (0130872) byronclark (reporter) - 2011-01-21 11:59
 https://issues.asterisk.org/view.php?id=18658#c130872 
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gdb-channel.txt shows the contents of the chan variable when __ast_read()
is called immediately before the crash. 

Issue History 
Date Modified    Username       Field                    Change               
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2011-01-21 11:59 byronclark     Note Added: 0130872                          
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