Crash while receiving was over T.38


Asterisk 1.8.23 crashes while receiving fax over T.38. Any suggestions how to fix that?

Message log shows:
WARNING[29508] res_fax.c: channel ‘Local/90024@mor_local-00000000;2’ timed-out during the T.38 negotiation.

Core dump bt:
(gdb) bt

#0 0x0000000000000000 in ?? ()

#1 0x00007f5fbc4b913d in t38_core_rx_ifp_stream (s=0x7f5f7c057988, buf=,

len=<value optimized out>, log_seq_no=0) at t38_core.c:417

#2 0x00007f5fbc4b977a in t38_core_rx_ifp_packet (s=0x7f5f7c057988, buf=0x7f5f600dc868 “\006UDPTL”, len=1, seq_no=0)

at t38_core.c:689

#3 0x00007f5fcb9e357d in generic_fax_exec (chan=0x7f5f9c009038, details=0x7f5f7c02b208,

reserved=<value optimized out>, token=<value optimized out>) at res_fax.c:1333

#4 0x00007f5fcb9e63d6 in receivefax_exec (chan=0x7f5f9c009038, data=) at res_fax.c:1770

#5 0x00000000004f5f6b in pbx_exec (c=0x7f5f9c009038, app=0x1dad3f0,

data=0x7f5facb89660 "/var/spool/asterisk/faxes/1409915501.172.tif,f") at pbx.c:1446

#6 0x0000000000500fb4 in pbx_extension_helper (c=0x7f5f9c009038, con=0x0, context=0x7f5f9c009590 “mor_fax2email”,

exten=0x7f5f9c0095e0 "9001224", priority=5, label=0x7f5facb89660 "/var/spool/asterisk/faxes/1409915501.172.tif,f", 

callerid=0x7f5f9c00a1a0 "0645567", action=E_SPAWN, found=0x7f5facb8bcdc, combined_find_spawn=1) at pbx.c:4489

#7 0x0000000000506784 in ast_spawn_extension (c=0x7f5f9c009038, args=0x0) at pbx.c:5127

#8 __ast_pbx_run (c=0x7f5f9c009038, args=0x0) at pbx.c:5230

#9 0x000000000050821b in pbx_thread (data=) at pbx.c:5571

#10 0x00000000005436bb in dummy_start (data=) at utils.c:1075

#11 0x00007f5ff5e729d1 in start_thread () from /lib64/

#12 0x00007f5ff38fa86d in clone () from /lib64/


This appears to be in third party code (t38_core.c). If you are using Free Fax for Asterisk, I’m not sure if there is any mechanism for reporting bugs. Note that there is a separate forum for peer support.

If you have a commercial licence for it, use the commercial support channels.

Note that it is difficult to get a crash report actioned, for the open source part of Asterisk, unless you disable optimisation when you build it.