Hi,

I'm running 2.2.36 (as provided by openSUSE in their server:mail repository) and at least at one of my systems LMTP is crashing regularly on certain messages (apparently a lot of them).

Sometimes (but not always a backtrace is posted to the logs:

2018-07-11T07:34:56.741848+02:00 saruman dovecot: lmtp(14690): Fatal: master: service(lmtp): child 14690 killed with signal 11 (core dumps disabled)
2018-07-11T07:34:56.820474+02:00 saruman dovecot: lmtp(an007498): Panic: file imap-bodystructure.c: line 116 (part_write_body_multipart): assertion failed: (p
art->data != NULL)
2018-07-11T07:34:56.821410+02:00 saruman dovecot: lmtp(an007498): Error: Raw backtrace: /usr/lib64/dovecot/libdovecot.so.0(+0xa0eb0) [0x7ff54949ceb0] -> /usr/
lib64/dovecot/libdovecot.so.0(+0xa0f8e) [0x7ff54949cf8e] -> /usr/lib64/dovecot/libdovecot.so.0(i_fatal+0) [0x7ff549430f46] -> /usr/lib64/dovecot/libdovecot.so
.0(imap_bodystructure_write+0x3b1) [0x7ff5494753b1] -> /usr/lib64/dovecot/libdovecot-storage.so.0(+0xb8ff5) [0x7ff5497e9ff5] -> /usr/lib64/dovecot/libdovecot-
storage.so.0(+0xbbbdc) [0x7ff5497ecbdc] -> /usr/lib64/dovecot/libdovecot-storage.so.0(index_mail_get_special+0x20d) [0x7ff5497ed05d] -> /usr/lib64/dovecot/lib
dovecot-storage.so.0(mail_get_special+0xd) [0x7ff54977325d] -> /usr/lib64/dovecot/libdovecot-storage.so.0(mail_set_attachment_keywords+0x162) [0x7ff549773662]
 -> /usr/lib64/dovecot/libdovecot-storage.so.0(+0xb9995) [0x7ff5497ea995] -> /usr/lib64/dovecot/libdovecot-storage.so.0(+0xb9d6b) [0x7ff5497ead6b] -> /usr/lib
64/dovecot/libdovecot-storage.so.0(index_mail_get_parts+0x60) [0x7ff5497ec850] -> /usr/lib64/dovecot/libdovecot-storage.so.0(mail_get_parts+0x23) [0x7ff549772
cb3] -> /usr/lib64/dovecot/libdovecot-sieve.so.0(+0x2ed1e) [0x7ff544fefd1e] -> /usr/lib64/dovecot/libdovecot-sieve.so.0(sieve_message_body_get_text+0x33) [0x7
ff544ff1283] -> /usr/lib64/dovecot/libdovecot-sieve.so.0(ext_body_get_part_list+0x47) [0x7ff545024ec7] -> /usr/lib64/dovecot/libdovecot-sieve.so.0(+0x64612) [
0x7ff545025612] -> /usr/lib64/dovecot/libdovecot-sieve.so.0(sieve_interpreter_continue+0x6c) [0x7ff545002e4c] -> /usr/lib64/dovecot/libdovecot-sieve.so.0(siev
e_interpreter_run+0x2b) [0x7ff54500309b] -> /usr/lib64/dovecot/libdovecot-sieve.so.0(+0x543e2) [0x7ff5450153e2] -> /usr/lib64/dovecot/libdovecot-sieve.so.0(si
eve_multiscript_run+0x38) [0x7ff545016018] -> /usr/lib64/dovecot/modules/lib90_sieve_plugin.so(+0x36a7) [0x7ff54527e6a7] -> /usr/lib64/dovecot/libdovecot-lda.
so.0(mail_deliver+0xa2) [0x7ff549a81eb2] -> dovecot/lmtp(+0x79ca) [0x5574fc4519ca] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_call_io+0x52) [0x7ff5494b1fd2
] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_handler_run_internal+0xe7) [0x7ff5494b3577] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_handler_run+0x3c) [0
x7ff5494b206c] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_run+0x38) [0x7ff5494b2228]

Any idea?

thanks,

 Wolfgang