[Kamailio-Users] Core dump on writing dialog profile size into script var.

[Alex Balashov]

It would seem that the malloc for the script var occasionally fails, 
which may or may not be central to the issue:

[SWITCH] Relaying BYE from 210.23.22.23 to sip:2122222322 at 210.23.22.23 
(DTAG=706
[SWITCH] [D] No dialog affinity for this BYE
Oct 16 05:03:32 [8710] ERROR:core:set_var_value: out of pkg mem!
Oct 16 05:03:32 [8710] ERROR:dialog:w_get_profile_size: cannot set svar
[SWITCH] [D] Profile size for 7709600101 now: 0
[ONREPLY-ROUTE 2] Received 200 for BYE
Relaying INVITE from 210.23.22.23 to sip:2122222322 at 210.23.22.23:5060
[D] Added new dialog for 7709600101
[ONREPLY-ROUTE 1] Provisional reply 100 received.
[ONREPLY-ROUTE 1] 200 OK received for 7709600101
[ONREPLY-ROUTE 1] INVITE/200 is part of dialog for 7709600101
[ONREPLY-ROUTE 1] Dialog profile size is: >
[SWITCH] Relaying ACK from 210.23.22.23 to sip:2122222322 at 210.23.22.23 
(DTAG=706
[SWITCH] [D] No dialog affinity for this ACK
Segmentation fault (core dumped)


Alex Balashov wrote:

> I also have another interesting problem with the aforementioned 
> configuration (http://pastebin.com/f28051a5).
> 
> When I write the dialog profile size into an AVP, it works fine.
> 
> When I write it into a script var, i.e. replace $avp(S:dlg_sz) with 
> $var(dlg_sz), it crashes:
> 
> Relaying INVITE from 210.23.22.23 to sip:2122222322 at 210.23.22.23:5060
> [D] Added new dialog for 7709600101
> [ONREPLY-ROUTE 1] Provisional reply 100 received.
> [ONREPLY-ROUTE 1] 200 OK received for 7709600101
> [ONREPLY-ROUTE 1] INVITE/200 is part of dialog for 7709600101
> Segmentation fault (core dumped)
> 
> GDB reveals:
> 
> Program received signal SIGSEGV, Segmentation fault.
> 0xb7e7f2f8 in strncpy () from /lib/i686/nosegneg/libc.so.6
> (gdb) where
> #0  0xb7e7f2f8 in strncpy () from /lib/i686/nosegneg/libc.so.6
> #1  0x080a4a07 in set_var_value (var=0x8188d98, value=0xbfae5f28, 
> flags=<value o
>      at script_var.c:122
> #2  0xb7d6c4fe in w_get_profile_size (msg=0x81902b8, profile=0xb5ede180 
> "\034??\
>      value=0x818b6b8 "@?\030\b", result=0x818b6f8 "N") at dialog.c:668
> #3  0x08054f15 in do_action (a=0x818b850, msg=0x81902b8) at action.c:850
> #4  0x08053ed2 in run_action_list (a=0x818b5c8, msg=0x81902b8) at 
> action.c:138
> #5  0x08056365 in do_action (a=0x818bab8, msg=0x81902b8) at action.c:722
> #6  0x08053ed2 in run_action_list (a=0x818b178, msg=0x81902b8) at 
> action.c:138
> #7  0x080572c2 in run_top_route (a=0x818b178, msg=0x81902b8) at action.c:118
> #8  0xb7de3a64 in reply_received (p_msg=0x81902b8) at t_reply.c:1361
> #9  0x08064793 in forward_reply (msg=0x81902b8) at forward.c:507
> #10 0x08090d5b in receive_msg (
>      buf=0x81600e0 "SIP/2.0 200 OK\r\nVia: SIP/2.0/UDP 
> 215.22.22.22;branch=z9hG4
> 08.52.173.18\r\nVia: SIP/2.0/UDP 
> 198.225.86.10:5060;branch=z9hG4bKragjo0207gm0dc
> p:208.52."..., len=814, rcv_info=0xbfae65d4) at receive.c:203
> #11 0x080cccfb in udp_rcv_loop () at udp_server.c:449
> #12 0x0806b78d in main (argc=1, argv=0xbfae6764) at main.c:693
> 
> It would seem to me that there is some sort of buffer overflow issue 
> that results in the garbage seen above.
> 
> Not sure that it makes a difference, but the glibc being linked against 
> is a Xen-safe one that disables TLS functionality.  This is all running 
> inside a Xen DomU.
> 


-- 
Alex Balashov
Evariste Systems
Web    : http://www.evaristesys.com/
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