2.2.25 dumps core with "Panic: file imap-client.c: line 837 (client_check_command_hangs): assertion failed: (client->io != NULL)"

[Aki Tuomi]

On 29.08.2016 15:00, Piper Andreas wrote:
> Hello,
>
> Dovecot 2.2.25
> OS: Solaris 11 (SunOS 5.11 11.3 i86pc i386 i86pc)
> Virtualization: VMware
> Filesystem: ZFS
> active users: ~4000
>
> About once a day Dovecot crashes with
> "Panic: file imap-client.c: line 837 (client_check_command_hangs):
> assertion failed: (client->io != NULL)"
>
> The log shows in each case:
>
> Aug 29 12:59:00 surz113 dovecot: [ID 583609 mail.crit] imap(username):
> Panic: file imap-client.c: line 837 (client_check_command_hangs):
> assertion failed: (client->io != NULL)
> Aug 29 12:59:00 surz113 dovecot: [ID 583609 mail.error] imap(username):
> Error: Raw backtrace: 0xffff80ffb6f3d88d -> 0xffff80ffb6f6ae82 ->
> 0x41eba0 -> 0x41ecf3 -> 0xffff80ffb6f5d248 -> 0xffff80ffb6f50d2f ->
> 0xffff80ffb6f519e0 -> 0xffff80ffb6f50dce -> 0xffff80ffb6f50f90 ->
> 0xffff80ffb6ee3ebb -> 0x42f169 -> 0x41292c
> Aug 29 12:59:00 surz113 dovecot: [ID 583609 mail.crit] imap(username):
> Fatal: master: service(imap): child 1461 killed with signal 6 (core not
> dumped - set service imap { drop_priv_before_exec=yes })
>
> It happens with different users, all with mailbox-sizes of 9 to 17
> GByte. The server stops completely for all users with this Panic and is
> then restarted automatically from Solaris Service Management.
>
> Find attached the output of 'doveconf -n'.
>
> Please let me know, if you need any more infos.
>
> Thanks for any help on this issue,
> Andreas, postmaster at uni-marburg.de

Hi!

Thank you for your report, we are looking into this.

Aki Tuomi
Dovecot oy