Exit status code 134; what is it, in the context of Dovecot Antispam plug-in?

[Ben Johnson]

On 8/7/2014 11:14 AM, Steffen Kaiser wrote:
> one idea: http://www.tldp.org/LDP/abs/html/exitcodes.html
> 
> exit code 134 would be in bash's meaning (if this website is
> correct all) some program died off signal 6. This would be Abort in
> Linux.
> 
> prepend your script with
> 
> exec >> /tmp/trace 2>&1 set -vx
> 
> that will dump anything visible into /tmp/trace
> 
> - -- Steffen Kaiser

Thank you for your continued assistance, Steffen.

You seem to be exactly correct with the Abort signal.

I prepended the values you suggested to the pipe script and here's the
relevant output:

+ /usr/lib/dovecot/deliver -d sa-training at example.com -m Training.SPAM
^A^H5584 prefix=lda:
^A^F5584 io_add(0x1) called twice fd=7, callback=0x7f23489fb6f0 ->
0x7f23489aa530
^A^D5584 Raw backtrace: /usr/lib/dovecot/libdovecot.so.0(+0x5e271)
[0x7f23489e9271] -> /usr/lib/dovecot/libdovecot.so.0(+0x5e34e)
[0x7f23489e934e] -> /usr/lib/dovecot/libdovecot.so.0(i_fatal+0)
[0x7f23489a4a9e] ->
/usr/lib/dovecot/libdovecot.so.0(ioloop_iolist_add+0x83)
[0x7f23489f9533] ->
/usr/lib/dovecot/libdovecot.so.0(io_loop_handle_add+0x3b)
[0x7f23489f9cbb] -> /usr/lib/dovecot/libdovecot.so.0(io_add+0x9b)
[0x7f23489f89fb] ->
/usr/lib/dovecot/libdovecot.so.0(master_service_io_listeners_add+0x69)
[0x7f23489a9e49] ->
/usr/lib/dovecot/libdovecot.so.0(master_service_init_finish+0xb0)
[0x7f23489a9f90] -> /usr/lib/dovecot/deliver(main+0x1cb)
[0x7f234939269b] ->
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf5)
[0x7f23485e6ec5] -> /usr/lib/dovecot/deliver(+0x31de) [0x7f23493931de]
/usr/local/bin/sa-learn-pipe.sh: line 52:  5584 Aborted
  (core dumped) /usr/lib/dovecot/deliver -d "sa-training at example.com"
-m "Training.$mode"
+ echo 'Exit status was 134'

Does this tell us anything more?

I don't see any indication that apparmor is at play, as there is no
profile that should apply in this context (and there is nothing in the
relevant log file):

# service apparmor status
apparmor module is loaded.
8 profiles are loaded.
8 profiles are in enforce mode.
   /sbin/dhclient
   /usr/bin/freshclam
   /usr/lib/NetworkManager/nm-dhcp-client.action
   /usr/lib/connman/scripts/dhclient-script
   /usr/sbin/clamd
   /usr/sbin/mysqld
   /usr/sbin/ntpd
   /usr/sbin/tcpdump
0 profiles are in complain mode.
4 processes have profiles defined.
4 processes are in enforce mode.
   /usr/bin/freshclam (2015)
   /usr/sbin/clamd (1897)
   /usr/sbin/mysqld (1239)
   /usr/sbin/ntpd (2472)
0 processes are in complain mode.
0 processes are unconfined but have a profile defined.

I'll try to reproduce this on an identically-configured server. I
wonder if it would be worth changing the version of Dovecot. But I
hate to play whack-a-mole if a more systematic approach is to be had.

Thanks again,

-Ben