[asterisk-bugs] [Asterisk 0017636]: Manager GetVar on unset variable causes segfault

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=17636 
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Reported By:                bklang
Assigned To:                tilghman
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Project:                    Asterisk
Issue ID:                   17636
Category:                   Core/ManagerInterface
Reproducibility:            always
Severity:                   crash
Priority:                   normal
Status:                     closed
Asterisk Version:           SVN 
JIRA:                       SWP-1847 
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): 1.6.2 
SVN Revision (number only!): 275996 
Request Review:              
Resolution:                 fixed
Fixed in Version:           
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Date Submitted:             2010-07-13 13:02 CDT
Last Modified:              2010-07-16 13:14 CDT
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Summary:                    Manager GetVar on unset variable causes segfault
Description: 
This appears to be the same type of bug as reported by me previously.

GetVar on a channel variable that is not set causes a vsnprintf() with a
null argument in a string field.  On OpenSolaris, this causes a segfault.

(gdb) bt
https://issues.asterisk.org/view.php?id=0  0xce8a47a0 in countbytes () from
/usr/lib/libc.so.1
https://issues.asterisk.org/view.php?id=1  0xce8f0793 in _ndoprnt () from
/usr/lib/libc.so.1
https://issues.asterisk.org/view.php?id=2  0xce8f31bd in vsnprintf () from
/usr/lib/libc.so.1
https://issues.asterisk.org/view.php?id=3  0x0813639d in __ast_str_helper
(buf=0xca74d13c, max_len=0, append=0, 
    fmt=0x817897c "Variable: %s\r\nValue: %s\r\n\r\n", ap=0xca74d15c
"Z####)
    at strings.c:72
https://issues.asterisk.org/view.php?id=4  0x080eab0c in astman_append
(s=0xca74df64, 
    fmt=0x817897c "Variable: %s\r\nValue: %s\r\n\r\n") at strings.h:767
https://issues.asterisk.org/view.php?id=5  0x080ed302 in action_getvar
(s=0xca74df64, m=0xca74dd24) at
manager.c:1925
https://issues.asterisk.org/view.php?id=6  0x080f0be6 in process_message
(s=0xca74df64, m=0xca74dd24)
    at manager.c:3069
https://issues.asterisk.org/view.php?id=7  0x080f11c4 in do_message
(s=0xca74df64) at manager.c:3189
https://issues.asterisk.org/view.php?id=8  0x080f13fc in session_do
(data=0x88544c8) at manager.c:3261
https://issues.asterisk.org/view.php?id=9  0x08141535 in dummy_start (data=0x0)
at utils.c:968
https://issues.asterisk.org/view.php?id=10 0xce92cd66 in _thrp_setup () from
/usr/lib/libc.so.1
https://issues.asterisk.org/view.php?id=11 0xce92cff0 in __csigsetjmp () from
/usr/lib/libc.so.1
https://issues.asterisk.org/view.php?id=12 0x00000000 in ?? ()
======================================================================
Relationships       ID      Summary
----------------------------------------------------------------------
related to          0016689 [patch] Crash in res_agi when trying to...
related to          0016504 Segfault in res_agi with no second para...
related to          0017087 [patch] Segfault in manager event after...
====================================================================== 

---------------------------------------------------------------------- 
 (0124630) svnbot (reporter) - 2010-07-16 13:14
 https://issues.asterisk.org/view.php?id=17636#c124630 
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Repository: asterisk
Revision: 277263

_U  trunk/
U   trunk/main/manager.c

------------------------------------------------------------------------
r277263 | tilghman | 2010-07-16 13:14:04 -0500 (Fri, 16 Jul 2010) | 12
lines

Merged revisions 277261 via svnmerge from 
https://origsvn.digium.com/svn/asterisk/branches/1.4

........
  r277261 | tilghman | 2010-07-16 13:04:11 -0500 (Fri, 16 Jul 2010) | 5
lines
  
  If variable gotten is not set, will segfault on Solaris.
  
  (closes issue https://issues.asterisk.org/view.php?id=17636)
   Reported by: bklang
........

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http://svn.digium.com/view/asterisk?view=rev&revision=277263 

Issue History 
Date Modified    Username       Field                    Change               
====================================================================== 
2010-07-16 13:14 svnbot         Checkin                                      
2010-07-16 13:14 svnbot         Note Added: 0124630                          
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