panic when using dovecot master account

[André Rodier]

On Sat, 2019-01-12 at 19:11 +0000, André Rodier via dovecot wrote:
> On 2018-11-09 07:40, André Rodier wrote:
> > On 2018-11-09 05:25, Aki Tuomi wrote:
> > > This seems to have nothing to do with master account or not. Does this
> > > happen if you try to open the virtual mailbox again?
> > > 
> > > Aki
> > > 
> > > > On 09 November 2018 at 00:13 André Rodier <andre at rodier.me> wrote:
> > > > 
> > > > 
> > > > Hello,
> > > > 
> > > > I am running dovecot 2.2.34 (874deae), on Debian stable, from 
> > > > backports.
> > > > 
> > > > I just tried the master account, and although everything worked in 
> > > > the
> > > > email client, I had logs in the error logs:
> > > > 
> > > > 
> > > > > imap(mirina): Panic: file mail-index-sync.c: line 413
> > > > > (mail_index_sync_begin_to2): assertion failed: (!index->syncing)
> > > > > Nov 08 22:06:24 osaka dovecot[1450]: imap(mirina): Error: Raw
> > > > > backtrace: /usr/lib/dovecot/libdovecot.so.0(+0x9e412) [0x7f20ae813412]
> > > > > -> /usr/lib/dovecot/libdovecot.so.0(+0x9e50d) [0x7f20ae81350d] ->
> > > > > /usr/lib/dovecot/libdovecot.so.0(i_fatal+0) [0x7f20ae7a2c51] ->
> > > > > /usr/lib/dovecot/libdovecot-storage.so.0(+0xe0fe4) [0x7f20aeb88fe4] ->
> > > > > /usr/lib/dovecot/libdovecot-storage.so.0(mail_index_sync_begin_to+0x4f)
> > > > > [0x7f20aeb890bf] ->
> > > > > /usr/lib/dovecot/libdovecot-storage.so.0(mail_index_sync_begin+0x1c)
> > > > > [0x7f20aeb8915c] ->
> > > > > /usr/lib/dovecot/modules/lib20_virtual_plugin.so(virtual_storage_sync_init+0x218)
> > > > > [0x7f20ad51f308] ->
> > > > > /usr/lib/dovecot/libdovecot-storage.so.0(mailbox_sync_init+0x44)
> > > > > [0x7f20aeaf02d4] ->
> > > > > /usr/lib/dovecot/libdovecot-storage.so.0(mailbox_sync+0x37)
> > > > > [0x7f20aeaf0387] ->
> > > > > /usr/lib/dovecot/libdovecot-storage.so.0(index_storage_get_status+0x31)
> > > > > [0x7f20aeb6bbf1] ->
> > > > > /usr/lib/dovecot/modules/lib20_virtual_plugin.so(+0x936d)
> > > > > [0x7f20ad51c36d] -> /usr/lib/dovecot/libdovecot-storage.so.0(+0xa8771)
> > > > > [0x7f20aeb50771] ->
> > > > > /usr/lib/dovecot/modules/lib20_fts_plugin.so(+0xfd46) [0x7f20adb8bd46]
> > > > > -> /usr/lib/dovecot/libdovecot-storage.so.0(mailbox_get_status+0x31)
> > > > > [0x7f20aeaf0781] ->
> > > > > /usr/lib/dovecot/modules/lib20_virtual_plugin.so(virtual_storage_sync_init+0x10b8)
> > > > > [0x7f20ad5201a8] ->
> > > > > /usr/lib/dovecot/libdovecot-storage.so.0(mailbox_sync_init+0x44)
> > > > > [0x7f20aeaf02d4] ->
> > > > > /usr/lib/dovecot/libdovecot-storage.so.0(mailbox_sync+0x37)
> > > > > [0x7f20aeaf0387] ->
> > > > > /usr/lib/dovecot/libdovecot-storage.so.0(index_storage_get_status+0x31)
> > > > > [0x7f20aeb6bbf1] ->
> > > > > /usr/lib/dovecot/modules/lib20_virtual_plugin.so(+0x936d)
> > > > > [0x7f20ad51c36d] -> /usr/lib/dovecot/libdovecot-storage.so.0(+0xa8771)
> > > > > [0x7f20aeb50771] ->
> > > > > /usr/lib/dovecot/modules/lib20_fts_plugin.so(+0xfd46) [0x7f20adb8bd46]
> > > > > -> /usr/lib/dovecot/libdovecot-storage.so.0(mailbox_get_status+0x31)
> > > > > [0x7f20aeaf0781] ->
> > > > > /usr/lib/dovecot/modules/lib20_virtual_plugin.so(virtual_storage_sync_init+0x10b8)
> > > > > [0x7f20ad5201a8] ->
> > > > > /usr/lib/dovecot/libdovecot-storage.so.0(mailbox_sync_init+0x44)
> > > > > [0x7f20aeaf02d4] ->
> > > > > /usr/lib/dovecot/libdovecot-storage.so.0(mailbox_sync+0x37)
> > > > > [0x7f20aeaf0387] -> dovecot/imap(cmd_select_full+0x16b)
> > > > > [0x557de970cc3b] -> dovecot/imap(command_exec+0x5c) [0x557de971444c] ->
> > > > > dovecot/imap(+0x1a912) [0x557de9712912]
> > > > > Nov 08 22:06:24 osaka dovecot[1450]: imap(mirina): Fatal: master:
> > > > > service(imap): child 4289 killed with signal 6 (core dumps disabled)
> > > > 
> > > > I attach my dovecot configuration too.
> > > > 
> > > > Thanks for your help.
> > > > 
> > 
> > Hello Aki,
> > 
> > You are right, the same error happens, even if I do not use the master 
> > password.
> > 
> > The weird thing is that it happens only with one specific account. For
> > this account, the virtual folders I have don't work, but they work for
> > the other accounts.
> > 
> > I do not have too much time to investigate now, but I will continue
> > this weekend.
> > 
> > Kind regards,
> > André
> 
> Happy new year, everyone!
> 
> Aki, I have been able to reproduce the problem, and this time, with the 
> packages from Debian stable. So you were right, this had nothing to do 
> with master user, but virtual folders.
> 
> I can now send the full stack trace, and doveconf.
> 
> Package versions:
> 
> ii  dovecot-core           1:2.2.27-3+deb9u2 amd64        secure 
> POP3/IMAP server - core files
> ii  dovecot-dbg            1:2.2.27-3+deb9u2 amd64        secure 
> POP3/IMAP server - debug symbols
> ii  dovecot-imapd          1:2.2.27-3+deb9u2 amd64        secure 
> POP3/IMAP server - IMAP daemon
> ii  dovecot-ldap           1:2.2.27-3+deb9u2 amd64        secure 
> POP3/IMAP server - LDAP support
> ii  dovecot-lmtpd          1:2.2.27-3+deb9u2 amd64        secure 
> POP3/IMAP server - LMTP server
> ii  dovecot-managesieved   1:2.2.27-3+deb9u2 amd64        secure 
> POP3/IMAP server - ManageSieve server
> ii  dovecot-pop3d          1:2.2.27-3+deb9u2 amd64        secure 
> POP3/IMAP server - POP3 daemon
> ii  dovecot-sieve          1:2.2.27-3+deb9u2 amd64        secure 
> POP3/IMAP server - Sieve filters support
> ii  dovecot-solr           1:2.2.27-3+deb9u2 amd64        secure 
> POP3/IMAP server - Solr support
> 
> 
> Kind regards,
> André
> 

I found what caused the crash:

the line "auto = subscribe" for the virtual folders.
Dovecot does not crash when I comment this line.

Thanks,
André