dovecot - Jan 2020 - Panic: file mail-index-util.c: line 10 (mail_index_uint32_to_offset): assertion failed: (offset < 0x40000000)

I'm trying this:

doveadm import -u restore at backup.invalid mdbox:/home/copymail2/mdbox
"" \
   mailbox INBOX header X-Spam Yes 
   
nd I'm getting:

doveadm(restore at backup.invalid): Panic: file mail-index-util.c: line 10
(mail_index_uint32_to_offset): assertion failed: (offset < 0x40000000)
doveadm(restore at backup.invalid): Error: Raw backtrace:
/usr/lib/dovecot/libdovecot.so.0(backtrace_append+0x42)
[0x7f598de6cac2] -> /usr/lib/dovecot/libdovecot.so.0(backtrace_get+0x1e) 
[0x7f598de6cbde] -> /usr/lib/dovecot/libdovecot.so.0(+0xe989e)
[0x7f598de7789e] -> /usr/lib/dovecot/libdovecot.so.0(+0xe98e1) 
[0x7f598de778e1] -> /usr/lib/dovecot/libdovecot.so.0(i_fatal+0) 
[0x7f598ddced04] ->
/usr/lib/dovecot/libdovecot-storage.so.0(mail_index_uint32_to_offset+0x78)
[0x7f598e227de8] ->
/usr/lib/dovecot/libdovecot-storage.so.0(mail_cache_add+0x83b)
[0x7f598e2103ab] ->
/usr/lib/dovecot/libdovecot-storage.so.0(index_mail_parse_header+0x449)
[0x7f598e1f2139] -> /usr/lib/dovecot/libdovecot.so.0(+0xc10a9)
[0x7f598de4f0a9] ->
/usr/lib/dovecot/libdovecot.so.0(i_stream_read_memarea+0x7a)
[0x7f598de852ea] -> /usr/lib/dovecot/libdovecot.so.0(i_stream_read+0x2f) 
[0x7f598de8562f] -> /usr/lib/dovecot/libdovecot.so.0(i_stream_read_data+0x3d)
[0x7f598de8600d] ->
/usr/lib/dovecot/libdovecot.so.0(message_parse_header_next+0x68)
[0x7f598de55a58] ->
/usr/lib/dovecot/libdovecot.so.0(message_parse_header+0x52)
[0x7f598de56432] -> /usr/lib/dovecot/libdovecot-storage.so.0(+0xcc561)
[0x7f598e1fc561] -> /usr/lib/dovecot/libdovecot-storage.so.0(+0xcd85c)
[0x7f598e1fd85c] ->
/usr/lib/dovecot/libdovecot-storage.so.0(index_storage_search_next_nonblock+0x11d)
[0x7f598e1fe04d] ->
/usr/lib/dovecot/libdovecot-storage.so.0(mailbox_search_next_nonblock+0x28)
[0x7f598e17df38] ->
/usr/lib/dovecot/libdovecot-storage.so.0(mailbox_search_next+0x3d)
[0x7f598e17df9d] -> doveadm(+0x31b13) 
[0x557f5d487b13] -> doveadm(+0x2c441)
[0x557f5d482441] -> doveadm(+0x2d1c9) 
[0x557f5d4831c9] -> doveadm(doveadm_cmd_ver2_to_mail_cmd_wrapper+0x20e) 
[0x557f5d48409e] -> doveadm(doveadm_cmd_run_ver2+0x55e)
[0x557f5d4953ee] -> doveadm(doveadm_cmd_try_run_ver2+0x37) 
[0x557f5d495447] -> doveadm(main+0x1d1)
[0x557f5d472211] -> /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe7)
[0x7f598d3cfb97] -> doveadm(_start+0x2a) [0x557f5d47272a] 
Aborted (core dumped)

I'm using 
ii  dovecot-core   2:2.3.9.2-1+ubuntu18.04 amd64        secure POP3/IMAP server
- core files
ii  dovecot-dbg    2:2.3.9.2-1+ubuntu18.04 amd64        secure POP3/IMAP server
- debug symbols
ii  dovecot-imapd  2:2.3.9.2-1+ubuntu18.04 amd64        secure POP3/IMAP server
- IMAP daemon
ii  dovecot-lmtpd  2:2.3.9.2-1+ubuntu18.04 amd64        secure POP3/IMAP server
- LMTP server
ii  dovecot-lucene 2:2.3.9.2-1+ubuntu18.04 amd64        secure POP3/IMAP server
- Lucene support
		
Running in gdb results in this backtrace:

Program received signal SIGABRT, Aborted.
__GI_raise (sig=sig at entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51
51../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) bt
#0  __GI_raise (sig=sig at entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51
#1  0x00007ffff68e4801 in __GI_abort () at abort.c:79
#2  0x00007ffff736d851 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  0x00007ffff736d8e1 in default_fatal_handler (ctx=<optimized out>,
format=<optimized out>, args=<optimized out>) at failures.c:479
#5  0x00007ffff72c4d04 in i_panic (format=format at entry=0x7ffff772dd00
"file %s: line %d (%s): assertion failed: (%s)") at failures.c:523
#6  0x00007ffff771dde8 in mail_index_uint32_to_offset (offset=<optimized
out>) at mail-index-util.c:10
#7  0x00007ffff77063ab in mail_cache_header_fields_write (ctx=0x555555855330,
buffer=<optimized out>, buffer=<optimized out>) at
mail-cache-transaction.c:609
#8  mail_cache_header_add_field (field_idx=15, ctx=0x555555855330) at
mail-cache-transaction.c:690
#9  mail_cache_add (ctx=0x555555855330, seq=1, field_idx=field_idx at entry=15,
data=0x7ffff773b6d6, data_size=0) at mail-cache-transaction.c:739
#10 0x00007ffff76ea82c in index_mail_cache_add_idx (mail=mail at
entry=0x555555869f18, field_idx=field_idx at entry=15, data=data at
entry=0x7ffff773b6d6, data_size=data_size at entry=0) at index-mail.c:631
#11 0x00007ffff76e8139 in index_mail_parse_header_finish (mail=<optimized
out>) at index-mail-headers.c:132
#12 index_mail_parse_header (part=<optimized out>, hdr=<optimized
out>, mail=<optimized out>) at index-mail-headers.c:312
#13 0x00007ffff73450a9 in read_header (mstream=0x555555874740) at
istream-header-filter.c:356
#14 i_stream_header_filter_read (stream=0x555555874740) at
istream-header-filter.c:446
#15 0x00007ffff737b2ea in i_stream_read_memarea (stream=stream at
entry=0x5555558747c0) at istream.c:313
#16 0x00007ffff737b62f in i_stream_read (stream=stream at entry=0x5555558747c0)
at istream.c:271
#17 0x00007ffff737c00d in i_stream_read_data (stream=0x5555558747c0,
data_r=data_r at entry=0x7fffffffdc08, size_r=size_r at entry=0x7fffffffdc10,
threshold=threshold at entry=1) at istream.c:745
#18 0x00007ffff734ba58 in i_stream_read_bytes (wanted=2, size_r=0x7fffffffdc10,
data_r=0x7fffffffdc08, stream=<optimized out>) at
../../src/lib/istream.h:217
#19 message_parse_header_next (ctx=0x555555869db0, hdr_r=hdr_r at
entry=0x7fffffffdc70) at message-header-parser.c:85
#20 0x00007ffff734c432 in message_parse_header (input=<optimized out>,
hdr_size=hdr_size at entry=0x0, flags=flags at
entry=MESSAGE_HEADER_PARSER_FLAG_CLEAN_ONELINE,
    callback=callback at entry=0x7ffff76f1aa0 <search_header>,
context=context at entry=0x7fffffffdce0) at message-header-parser.c:392
#21 0x00007ffff76f2561 in search_arg_match_text (ctx=0x555555856fa0,
args=0x5555558216d0) at index-search.c:759
#22 search_match_once (ctx=0x555555856fa0) at index-search.c:1399
#23 0x00007ffff76f385c in search_match_next (ctx=0x555555856fa0) at
index-search.c:1506
#24 search_more_with_mail (mail=<optimized out>, ctx=0x555555856fa0) at
index-search.c:1623
#25 search_more_with_prefetching (mail_r=<optimized out>,
ctx=<optimized out>) at index-search.c:1705
#26 search_more (ctx=ctx at entry=0x555555856fa0, mail_r=mail_r at
entry=0x7fffffffde10) at index-search.c:1779
#27 0x00007ffff76f404d in index_storage_search_next_nonblock
(_ctx=0x555555856fa0, mail_r=0x7fffffffdee0, tryagain_r=0x7fffffffde77) at
index-search.c:1807
#28 0x00007ffff7673f38 in mailbox_search_next_nonblock (ctx=0x555555856fa0,
mail_r=0x7fffffffdee0, tryagain_r=<optimized out>) at mail-storage.c:2307
#29 0x00007ffff7673f9d in mailbox_search_next (ctx=0x555555856fa0, mail_r=mail_r
at entry=0x7fffffffdee0) at mail-storage.c:2292
#30 0x0000555555586d52 in doveadm_mail_iter_next (iter=<optimized out>,
mail_r=mail_r at entry=0x7fffffffdee0) at doveadm-mail-iter.c:160
#31 0x0000555555585b13 in cmd_import_box (search_args=<optimized out>,
info=0x55555584e7b8, dest_user=<optimized out>, ctx=0x55555581fdb8) at
doveadm-mail-import.c:142
#32 cmd_import_run (_ctx=0x55555581fdb8, user=0x5555558374b8) at
doveadm-mail-import.c:202
#33 0x0000555555580441 in doveadm_mail_next_user (ctx=ctx at
entry=0x55555581fdb8, error_r=error_r at entry=0x7fffffffe0c0) at
doveadm-mail.c:462
#34 0x00005555555810db in doveadm_mail_single_user (ctx=ctx at
entry=0x55555581fdb8, error_r=error_r at entry=0x7fffffffe0c0) at
doveadm-mail.c:492
#35 0x00005555555811c9 in doveadm_mail_cmd_exec (ctx=ctx at
entry=0x55555581fdb8, wildcard_user=wildcard_user at entry=0x0) at
doveadm-mail.c:653
#36 0x000055555558209e in doveadm_cmd_ver2_to_mail_cmd_wrapper
(cctx=<optimized out>) at doveadm-mail.c:1144
#37 0x00005555555933ee in doveadm_cmd_run_ver2 (argc=10, argv=0x5555557f6bb8,
cctx=cctx at entry=0x7fffffffe2b0) at doveadm-cmd.c:575
#38 0x0000555555593447 in doveadm_cmd_try_run_ver2 (cmd_name=<optimized
out>, argc=<optimized out>, argv=<optimized out>,
cctx=0x7fffffffe2b0) at doveadm-cmd.c:497
#39 0x0000555555570211 in main (argc=<optimized out>, argv=<optimized
out>) at doveadm.c:395
(gdb) 

-- 
Ralf Hildebrandt
  Gesch?ftsbereich IT | Abteilung Netzwerk
  Charit? - Universit?tsmedizin Berlin
  Campus Benjamin Franklin
  Hindenburgdamm 30 | D-12203 Berlin
  Tel. +49 30 450 570 155 | Fax: +49 30 450 570 962
  ralf.hildebrandt at charite.de | https://www.charite.de