Sumbission crashes when relaying over TLS

[Alec Moskvin]

Hello,

I'm trying to set up the submission proxy, but if I set
submission_relay_ssl = starttls, it crashes. Without it, it works.

Please find the details below.

Thanks,
Alec


dovecot[256855]: submission-login: Login: user=<alec>, method=PLAIN, rip=::1, lip=::1, mpid=257033, secured, session=<kMd1B9uthLUAAAAAAAAAAAAAAAAAAAAB>
dovecot[256855]: submission(alec)<257033><kMd1B9uthLUAAAAAAAAAAAAAAAAAAAAB>: Panic: file smtp-client-connection.c: line 290 (smtp_client_connection_fail): assertion failed: (conn->to_connect == NULL)
dovecot[256855]: submission(alec)<257033><kMd1B9uthLUAAAAAAAAAAAAAAAAAAAAB>: Error: Raw backtrace: /usr/lib64/dovecot/libdovecot.so.0(backtrace_append+0x42) [0x7fbbfb2bcaf2] -> /usr/lib64/dovecot/libdovecot.so.0(backtrace_get+0x1e) [0x7fbbfb2bcc0e] -> /usr/lib64/dovecot/libdovecot.so.0(+0xf5f09) [0x7fbbfb2c5f09] -> /usr/lib64/dovecot/libdovecot.so.0(+0xf5fa1) [0x7fbbfb2c5fa1] -> /usr/lib64/dovecot/libdovecot.so.0(+0x51eec) [0x7fbbfb221eec] -> /usr/lib64/dovecot/libdovecot.so.0(+0x44d5e) [0x7fbbfb214d5e] -> /usr/lib64/dovecot/libdovecot.so.0(+0x6c431) [0x7fbbfb23c431] -> /usr/lib64/dovecot/libdovecot.so.0(smtp_client_command_input_reply+0x201) [0x7fbbfb235261] -> /usr/lib64/dovecot/libdovecot.so.0(+0x6ccfd) [0x7fbbfb23ccfd] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_call_io+0x68) [0x7fbbfb2dc048] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_handler_run_internal+0x132) [0x7fbbfb2dd662] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_handler_run+0x51) [0x7fbbfb2dc0f1] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_run+0x40) [0x7fbbfb2dc2b0] -> /usr/lib64/dovecot/libdovecot.so.0(master_service_run+0x13) [0x7fbbfb255ee3] -> dovecot/submission(main+0x4df) [0x561d486b3daf] -> /lib64/libc.so.6(__libc_start_main+0xea) [0x7fbbfb054b8a] -> dovecot/submission(_start+0x2a) [0x561d486b3e3a]
dovecot[256855]: submission(alec)<257033><kMd1B9uthLUAAAAAAAAAAAAAAAAAAAAB>: Fatal: master: service(submission): child 257033 killed with signal 6 (core dumped)


(gdb) bt
#0  0x00007fbbfb069a31 in raise () from /lib64/libc.so.6
#1  0x00007fbbfb0532b6 in abort () from /lib64/libc.so.6
#2  0x00007fbbfb22223c in default_fatal_finish (status=0, type=LOG_TYPE_PANIC) at failures.c:459
#3  fatal_handler_real (ctx=<optimized out>, format=<optimized out>, args=<optimized out>) at failures.c:471
#4  0x00007fbbfb2c5fa1 in i_internal_fatal_handler (ctx=<optimized out>, format=<optimized out>, args=<optimized out>) at failures.c:848
#5  0x00007fbbfb221eec in i_panic (format=format at entry=0x7fbbfb30fd08 "file %s: line %d (%s): assertion failed: (%s)") at failures.c:523
#6  0x00007fbbfb214d5e in smtp_client_connection_fail (status=9002, error=<optimized out>, conn=0x561d491296a8) at smtp-client-connection.c:290
#7  smtp_client_connection_fail (conn=0x561d491296a8, status=<optimized out>, error=<optimized out>) at smtp-client-connection.c:282
#8  0x00007fbbfb23c431 in smtp_client_connection_starttls_cb (reply=0x561d4912d048, conn=0x561d491296a8) at smtp-client-connection.c:788
#9  0x00007fbbfb235261 in smtp_client_command_input_reply (cmd=<optimized out>, reply=reply at entry=0x561d4912d048) at smtp-client-command.c:971
#10 0x00007fbbfb23ccfd in smtp_client_connection_input_reply (reply=0x561d4912d048, conn=0x561d491296a8) at smtp-client-connection.c:1045
#11 smtp_client_connection_input (_conn=<optimized out>) at smtp-client-connection.c:1116
#12 0x00007fbbfb2dc048 in io_loop_call_io (io=0x561d49109cb0) at ioloop.c:713
#13 0x00007fbbfb2dd662 in io_loop_handler_run_internal (ioloop=ioloop at entry=0x561d490fd050) at ioloop-epoll.c:222
#14 0x00007fbbfb2dc0f1 in io_loop_handler_run (ioloop=0x561d490fd050) at ioloop.c:765
#15 0x00007fbbfb2dc2b0 in io_loop_run (ioloop=0x561d490fd050) at ioloop.c:738
#16 0x00007fbbfb255ee3 in master_service_run (service=0x561d490fceb0, callback=<optimized out>) at master-service.c:851
#17 0x0000561d486b3daf in main (argc=<optimized out>, argv=<optimized out>) at main.c:396


$ openssl version
OpenSSL 1.1.1g  21 Apr 2020


# doveconf -n
# 2.3.11.3 (502c39af9): /etc/dovecot/dovecot.conf
# OS: Linux 5.8.4 x86_64 Gentoo Base System release 2.7
# Hostname: haswell
listen = localhost
mail_location = maildir:~/.maildir
namespace inbox {
  inbox = yes
  location =
  mailbox Drafts {
    special_use = \Drafts
  }
  mailbox Junk {
    special_use = \Junk
  }
  mailbox Sent {
    special_use = \Sent
  }
  mailbox "Sent Messages" {
    special_use = \Sent
  }
  mailbox Trash {
    special_use = \Trash
  }
  prefix =
}
passdb {
  args = scheme=CRYPT username_format=%u /etc/dovecot/users
  driver = passwd-file
}
protocols = submission
ssl_cert = </etc/ssl/dovecot/server.pem
ssl_client_ca_file = </etc/dovecot/ca.crt
ssl_key = # hidden, use -P to show it
submission_relay_host = localhost
submission_relay_port = 2525
submission_relay_rawlog_dir = %h/rawlog
submission_relay_ssl = starttls
userdb {
  args = username_format=%u /etc/dovecot/users
  driver = passwd-file
}
protocol submission {
  rawlog_dir = %h/rawlog
}