Hi There!
I run into this problem with virtual Mailboxes on release-2.3.2 (and also in master and in older versions of dovecot)
I added the core-file.
Jul 25 04:11:29 aldebaran dovecot[10573]: imap(jakob)<11292><rg2GZclxHaPAqADc>: Panic: Leaked view for index /var/lib/dovecot/db/indexes/Maildir/jakob/&ANY-BB/dovecot.index: Opened in index-storage.c:338 Jul 25 04:11:29 aldebaran dovecot[10573]: imap(jakob)<11292><rg2GZclxHaPAqADc>: Error: Raw backtrace: /usr/local/lib/dovecot/libdovecot.so.0(+0xcedf1) [0x7ffad9ac0df1] -> /usr/local/lib/dovecot/libdovecot.so.0(+ 0xceeba) [0x7ffad9ac0eba] -> /usr/local/lib/dovecot/libdovecot.so.0(i_fatal+0) [0x7ffad9a2efe8] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(+0xf7022) [0x7ffad9c66022] -> /usr/local/lib/dovecot/libdovecot-s torage.so.0(index_storage_mailbox_close+0x9a) [0x7ffad9c3d72a] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_close+0x1a) [0x7ffad9bbb1aa] -> /usr/local/lib/dovecot/lib20_virtual_plugin.so(+0xab80) [0 x7ffad9792b80] -> /usr/local/lib/dovecot/lib20_virtual_plugin.so(virtual_backend_box_open+0x2b) [0x7ffad9792d3b] -> /usr/local/lib/dovecot/lib20_virtual_plugin.so(virtual_storage_sync_init+0x12a9) [0x7ffad9795f1 9] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_sync_init+0x51) [0x7ffad9bbd6d1] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_sync+0x37) [0x7ffad9bbd787] -> /usr/local/lib/dovecot/libdo vecot-storage.so.0(index_storage_get_status+0x31) [0x7ffad9c3bed1] -> /usr/local/lib/dovecot/lib20_virtual_plugin.so(+0x9ead) [0x7ffad9791ead] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(+0xb0f83) [0x7ffad 9c1ff83] -> /usr/local/lib/dovecot/lib20_fts_plugin.so(+0x10602) [0x7ffad97b4602] -> /usr/local/lib/dovecot/lib01_acl_plugin.so(+0xf813) [0x7ffad99e9813] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox _get_status+0x31) [0x7ffad9bbdb91] -> /usr/local/lib/dovecot/lib20_virtual_plugin.so(virtual_storage_sync_init+0xf0b) [0x7ffad9795b7b] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_sync_init+0x51) [0 x7ffad9bbd6d1] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_sync+0x37) [0x7ffad9bbd787] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(index_storage_get_status+0x31) [0x7ffad9c3bed1] -> /usr/loca l/lib/dovecot/lib20_virtual_plugin.so(+0x9ead) [0x7ffad9791ead] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(+0xb0f83) [0x7ffad9c1ff83] -> /usr/local/lib/dovecot/lib20_fts_plugin.so(+0x10602) [0x7ffad97b460 2] -> /usr/local/lib/dovecot/lib01_acl_plugin.so(+0xf813) [0x7ffad99e9813] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_get_status+0x31) [0x7ffad9bbdb91] -> /usr/local/lib/dovecot/lib20_virtual_plug in.so(virtual_storage_sync_init+0xf0b) [0x7ffad9795b7b] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_sync_init+0x51) [0x7ffad9bbd6d1] Jul 25 04:11:29 aldebaran dovecot[10573]: imap(jakob)<11292><rg2GZclxHaPAqADc>: Fatal: master: service(imap): child 11292 killed with signal 6 (core dumped) Jul 25 04:11:29 aldebaran dovecot[10573]: auth: Debug: client in: AUTH 19 PLAIN service=imap secured=tls session=9KKNZclxHqPAqADc lip=192.168.0.14 rip=192.168.0.2 20 lport=143 rport=41758 local_name=aldebaran.xundeenergie.at ssl_cipher=ECDHE-RSA-AES128-GCM-SHA256 ssl_cipher_bits=128 ssl_pfs=KxECDHE ssl_protocol=TLSv1.2 Jul 25 04:11:29 aldebaran dovecot[10573]: auth: Debug: client passdb out: CONT 19 Jul 25 04:11:29 aldebaran dovecot[10573]: auth: Debug: client in: CONT<hidden> Jul 25 04:11:29 aldebaran dovecot[10573]: auth: Debug: passwd-file(jakob,192.168.0.220,<9KKNZclxHqPAqADc>): lookup: user=jakob file=/usr/local/etc/dovecot/users Jul 25 04:11:29 aldebaran dovecot[10573]: auth: Debug: client passdb out: OK 19 user=jakob Jul 25 04:11:29 aldebaran dovecot[10573]: auth: Debug: master in: REQUEST 2436366337 10570 19 dd4c468bbfe617d4ef06a1b8ce6c111d session_pid=11298 request_auth_token Jul 25 04:11:29 aldebaran dovecot[10573]: auth: Debug: passwd-file(jakob,192.168.0.220,<9KKNZclxHqPAqADc>): lookup: user=jakob file=/usr/local/etc/dovecot/users Jul 25 04:11:29 aldebaran dovecot[10573]: auth: Debug: master userdb out: USER 2436366337 jakob home=/var/mail/jakob acl_groups=home,admin auth_token=3ea3b630e131 3bf5beb0f26ff740450189f63e3e Jul 25 04:11:29 aldebaran dovecot[10573]: imap-login: Login: user=<jakob>, method=PLAIN, rip=192.168.0.220, lip=192.168.0.14, mpid=11298, TLS, session=<9KKNZclxHqPAqADc> Jul 25 04:11:29 aldebaran dovecot[10573]: imap(jakob)<11298><9KKNZclxHqPAqADc>: Panic: Leaked view for index /var/lib/dovecot/db/indexes/Maildir/jakob/&ANY-BB/dovecot.index: Opened in index-storage.c:338 Jul 25 04:11:29 aldebaran dovecot[10573]: imap(jakob)<11298><9KKNZclxHqPAqADc>: Error: Raw backtrace: /usr/local/lib/dovecot/libdovecot.so.0(+0xcedf1) [0x7fbd982b2df1] -> /usr/local/lib/dovecot/libdovecot.so.0(+ 0xceeba) [0x7fbd982b2eba] -> /usr/local/lib/dovecot/libdovecot.so.0(i_fatal+0) [0x7fbd98220fe8] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(+0xf7022) [0x7fbd98458022] -> /usr/local/lib/dovecot/libdovecot-s torage.so.0(index_storage_mailbox_close+0x9a) [0x7fbd9842f72a] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_close+0x1a) [0x7fbd983ad1aa] -> /usr/local/lib/dovecot/lib20_virtual_plugin.so(+0xab80) [0 x7fbd97f84b80] -> /usr/local/lib/dovecot/lib20_virtual_plugin.so(virtual_backend_box_open+0x2b) [0x7fbd97f84d3b] -> /usr/local/lib/dovecot/lib20_virtual_plugin.so(virtual_storage_sync_init+0x12a9) [0x7fbd97f87f1 9] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_sync_init+0x51) [0x7fbd983af6d1] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_sync+0x37) [0x7fbd983af787] -> /usr/local/lib/dovecot/libdo vecot-storage.so.0(index_storage_get_status+0x31) [0x7fbd9842ded1] -> /usr/local/lib/dovecot/lib20_virtual_plugin.so(+0x9ead) [0x7fbd97f83ead] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(+0xb0f83) [0x7fbd9 8411f83] -> /usr/local/lib/dovecot/lib20_fts_plugin.so(+0x10602) [0x7fbd97fa6602] -> /usr/local/lib/dovecot/lib01_acl_plugin.so(+0xf813) [0x7fbd981db813] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox _get_status+0x31) [0x7fbd983afb91] -> /usr/local/lib/dovecot/lib20_virtual_plugin.so(virtual_storage_sync_init+0xf0b) [0x7fbd97f87b7b] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_sync_init+0x51) [0 x7fbd983af6d1] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_sync+0x37) [0x7fbd983af787] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(index_storage_get_status+0x31) [0x7fbd9842ded1] -> /usr/loca l/lib/dovecot/lib20_virtual_plugin.so(+0x9ead) [0x7fbd97f83ead] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(+0xb0f83) [0x7fbd98411f83] -> /usr/local/lib/dovecot/lib20_fts_plugin.so(+0x10602) [0x7fbd97fa660 2] -> /usr/local/lib/dovecot/lib01_acl_plugin.so(+0xf813) [0x7fbd981db813] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_get_status+0x31) [0x7fbd983afb91] -> /usr/local/lib/dovecot/lib20_virtual_plug in.so(virtual_storage_sync_init+0xf0b) [0x7fbd97f87b7b] -> /usr/local/lib/dovecot/libdovecot-storage.so.0(mailbox_sync_init+0x51) [0x7fbd983af6d1] Jul 25 04:11:30 aldebaran dovecot[10573]: imap(jakob)<11298><9KKNZclxHqPAqADc>: Fatal: master: service(imap): child 11298 killed with signal 6 (core dumped)
jakob