Kernel panic in dovecot-ee-lmtp on Debian 8

[Stephan Bosch]

Op 25-4-2016 om 18:01 schreef Timo Sirainen:
> On 25 Apr 2016, at 13:48, Tobi <tobster at brain-force.ch> wrote:
>> Hi list
>>
>> I just realized that that I don not receive all mails in my mailbox
>> (running dovecot-ee 2.2.23.1-1 on Debian 8). On my frontend servers
>> (running postfix) the queue fills up with mails that cannot be delivered
>> via lmtp to my backend servers. The error message on the frontend is
>> "lost connection with backend while sending data"
>> When I checked the logs on the backend server I found upon every
>> delivery attempt kernel panics
>>
>> Apr 25 12:33:36 mbox1 dovecot: lmtp(REDACTED): Panic: epoll_ctl(del, 18)
>> failed: Bad file descriptor
>> Apr 25 12:33:36 mbox1 dovecot: lmtp(REDACTED): Error: Raw backtrace:
> Can you get a core dump and gdb backtrace? See http://dovecot.org/bugreport.html#coredumps
>
>> /usr/lib/dovecot/libdovecot-sieve.so.0(program_client_run+0xe8)
>> [0x7faa17d3b308] ->
>> /usr/lib/dovecot/modules/sieve/lib90_sieve_extprograms_plugin.so(+0x45b8) [0x7faa15d855b8]
>> ->
>> /usr/lib/dovecot/libdovecot-sieve.so.0(sieve_interpreter_continue+0x7c)
>> [0x7faa17cfa2ac] ->
>>
>> the weird thing is that this is not concerning all incoming mails. From
>> time to time the frontends can deliver messages to my backends. I just
>> tested it with a mail from work. It arrived via a frontend that has
>> other mails in queue that could not be delivered so far.
>>
>> Does anyone have an idea where I could look for the root cause of this
>> panic messages?
> Looks like somehow caused by sieve extprograms.

Probably this bug:

https://git.dovecot.net/pigeonhole/core/commit/a95b0579b89c13fb3ee5700e76cbe6a4a3e898e0

Fixed for upcoming release.

Regards,

Stephan.