[asterisk-bugs] [Asterisk 0017976]: Asterisk Crash on RTCP package in SRTP mode

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=17976 
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Reported By:                bernhards
Assigned To:                
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Project:                    Asterisk
Issue ID:                   17976
Category:                   Resources/res_srtp
Reproducibility:            always
Severity:                   crash
Priority:                   normal
Status:                     acknowledged
Asterisk Version:           SVN 
JIRA:                       SWP-2196 
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): 1.8 
SVN Revision (number only!): 285988 
Request Review:              
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Date Submitted:             2010-09-10 01:52 CDT
Last Modified:              2010-10-26 12:25 CDT
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Summary:                    Asterisk Crash on RTCP package in SRTP mode
Description: 
"snom360-SIP 8.4.18 42570" connected to Asterisk with TLS. snom makes an
outbound call to another phone (without srtp). Other telephone does ring -
then Asterisk does crash. 

libsrtp version 1.4.4. was used - without a change.
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 (0128406) 1stbs (reporter) - 2010-10-26 12:25
 https://issues.asterisk.org/view.php?id=17976#c128406 
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hello i got the same prob
i try to fix it and get follow analysis

the error occur in  svn/  trunk/ srtp/ crypto/ replay/ rdb.c 
exactly in the function rdb_add_index when it calls
v128_set_bit(&rdb->bitmask, rdb_bits_in_bitmask-delta);
i have added some debbuging information in the function
index is : 3010
rdb->window_start is : 0
rdb_bits_in_bitmask is : 128
delta in else tree is : 2883

rdb_bits_in_bitmask-delta= -2755
and with that negativ value you got the the core dump

right now i have just out commented the else tree to devoid the crash. it
seems to work but replay function is damaged a little bit.
Perhaps anybody here has a better idea to solve this issue 

Issue History 
Date Modified    Username       Field                    Change               
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2010-10-26 12:25 1stbs          Note Added: 0128406                          
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