last_login LDAP - killed with signal 11 (core dumped)

[Aki Tuomi]

On 22.03.2017 10:03, Leon Kyneur wrote:
> Hi
>
> I am trying to configure the last_login plugin with LDAP dictionary
> which is causing dict service to crash. Not sure if this is a bug or
> some configuration parameter I'm getting wrong?
>
> Running latest dovecot but was having the same problem in earlier
> version 2.2.25
>
> # dovecot --version
> 2.2.28 (bed8434)
>
> I have configured dovecot like so:
>
> dovecot.conf (before conf.d/*.conf:
> dict {
>   #quota = mysql:/etc/dovecot/dovecot-dict-sql.conf.ext
>   #expire = sqlite:/etc/dovecot/dovecot-dict-sql.conf.ext
>   lastlogin = ldap:/etc/dovecot/dovecot-ldap-dict.conf.ext
> }
>
> conf.d/10-master.conf
> service dict {
>   # If dict proxy is used, mail processes should have access to its
>   socket.
>   # For example: mode=0660, group=vmail and global
>   mail_access_groups=vmail
>   unix_listener dict {
>     mode = 0660
>     user = vmail
>     group = vmail
>   }
> }
>
>
> conf.d/20-imap.conf:
> protocol imap {
>   # Space separated list of plugins to load (default is global
>   mail_plugins).
>   mail_plugins = $mail_plugins last_login 
>
>   # Maximum number of IMAP connections allowed for a user from each IP
>   address.
>   # NOTE: The username is compared case-sensitively.
>   #mail_max_userip_connections = 10
> }
>
>
>
> 90-plugins.conf
> plugin {
>   #setting_name = value
>   #last_login_dict = proxy::lastlogin
>   last_login_dict = proxy:dict:lastlogin
>   zlib_save = gz
>   zlib_save_level = 6
> }
>
>
> dovecot-ldap-dict.conf.ext:
> uri = ldap://ldap.internal
> bind_dn = cn=Manager,dc=mail,dc=com
> password = XXXX
> tls = no
> debug = 1
>
> map {
>   pattern = last-login/$user
>   filter = (&(mail=%{user})(objectClass=mailUser)) # the () is required
>   base_dn = o=domains,dc=mail,dc=com 
>   username_attribute = mail
>   value_attribute = lastLoginTime
>   fields {
>     mail=$user
>   }
> }
>
> I don't see dovecot ever making a connection to the LDAP server I've
> configured in the dovecot-ldap-dict.conf.ext file. 
>
> Log shows
>
> ==> /var/log/dovecot.log <==
> Mar 22 07:49:30 imap-login: Info: Login: user=<leon at mail.com>,
> method=PLAIN, rip=X.X.X.X, lip=X.X.X.X, mpid=36105, secured,
> session=<o0Lu/0xL4N3LhgGR>
> Mar 22 07:49:30 dict: Fatal: master: service(dict): child 36107 killed
> with signal 11 (core dumped)
> Mar 22 07:49:30 imap(leon at mail.com): Error: dict-client: Commit may have
> failed: Connection closed (reply took 0.015 secs)
> Mar 22 07:49:30 imap(leon at mail.com): Error: last_login_dict: Write was
> unconfirmed (timeout or disconnect) for user leon at mail.com
>
> Backtrace:
>  # gdb /var/core/36107 
> GNU gdb (GDB) Red Hat Enterprise Linux 7.6.1-94.el7
> Copyright (C) 2013 Free Software Foundation, Inc.
> License GPLv3+: GNU GPL version 3 or later
> <http://gnu.org/licenses/gpl.html>
> This is free software: you are free to change and redistribute it.
> There is NO WARRANTY, to the extent permitted by law.  Type "show
> copying"
> and "show warranty" for details.
> This GDB was configured as "x86_64-redhat-linux-gnu".
> For bug reporting instructions, please see:
> <http://www.gnu.org/software/gdb/bugs/>...
> [New LWP 36107]
> Reading symbols from /usr/libexec/dovecot/dict...Reading symbols from
> /usr/lib/debug/usr/libexec/dovecot/dict.debug...done.
> done.
> Missing separate debuginfo for 
> Try: yum --enablerepo='*debug*' install
> /usr/lib/debug/.build-id/b0/07fede01895dec1aca9d8b8993fe27d70a3a20
> [Thread debugging using libthread_db enabled]
> Using host libthread_db library "/lib64/libthread_db.so.1".
> Core was generated by `dovecot/dict'.
> Program terminated with signal 11, Segmentation fault.
> #0  0x0000000000000000 in ?? ()
> (gdb) bt full
> #0  0x0000000000000000 in ?? ()
> No symbol table info available.
> #1  0x00007fbcf11bd04f in cmd_begin (cmd=0x7fbcf2c02910, line=<optimized
> out>) at dict-commands.c:365
>         trans = 0x7fbcf2c029a0
>         id = 1
> #2  0x00007fbcf11bdef8 in dict_command_input
> (conn=conn at entry=0x7fbcf2bf24d0, line=line at entry=0x7fbcf2bf48cb "B1") at
> dict-commands.c:625
>         cmd_func = 0x7fbcf13c85c0 <cmds+32>
>         cmd = 0x7fbcf2c02910
>         ret = <optimized out>
> #3  0x00007fbcf11bc6ee in dict_connection_input_more
> (conn=0x7fbcf2bf24d0) at dict-connection.c:117
>         _data_stack_cur_id = 3
>         line = 0x7fbcf2bf48cb "B1"
>         ret = <optimized out>
> #4  0x00007fbcf11bc7d2 in dict_connection_input (conn=0x7fbcf2bf24d0) at
> dict-connection.c:167
>         line = <optimized out>
>         conn = 0x7fbcf2bf24d0
> #5  0x00007fbcf0d1b2d2 in io_loop_call_io (io=0x7fbcf2bf2890) at
> ioloop.c:599
>         ioloop = 0x7fbcf2be0740
>         t_id = 2
>         __FUNCTION__ = "io_loop_call_io"
> #6  0x00007fbcf0d1c95f in io_loop_handler_run_internal
> (ioloop=ioloop at entry=0x7fbcf2be0740) at ioloop-epoll.c:223
>         ctx = 0x7fbcf2beded0
>         events = <optimized out>
>         list = 0x7fbcf2bf28f0
>         io = <optimized out>
>         tv = {tv_sec = 2147483, tv_usec = 0}
>         events_count = <optimized out>
>         msecs = <optimized out>
>         ret = 1
>         i = 0
>         call = <optimized out>
>         __FUNCTION__ = "io_loop_handler_run_internal"
> #7  0x00007fbcf0d1b36c in io_loop_handler_run
> (ioloop=ioloop at entry=0x7fbcf2be0740) at ioloop.c:648
> No locals.
> #8  0x00007fbcf0d1b528 in io_loop_run (ioloop=0x7fbcf2be0740) at
> ioloop.c:623
>         __FUNCTION__ = "io_loop_run"
> #9  0x00007fbcf0ca4603 in master_service_run (service=0x7fbcf2be05e0,
> callback=callback at entry=0x7fbcf11be150 <client_connected>) at
> master-service.c:641
> No locals.
> #10 0x00007fbcf11bbff9 in main (argc=1, argv=0x7fbcf2be0390) at
> main.c:161
>         set_roots = {0x7fbcf13c88a0 <dict_setting_parser_info>, 0x0}
>         error = 0x0

LDAP writes are not supported in LDAP dict module yet. It should not
crash though.

Aki