[Dovecot] Segfault on antispam plugin

[Allan Cassaro]

On Thu, Dec 11, 2008 at 7:49 AM, Allan Cassaro <allan.cassaro at gmail.com> wrote:
> On Thu, Dec 11, 2008 at 7:17 AM, Steffen Kaiser
> <skdovecot at smail.inf.fh-brs.de> wrote:
>> -----BEGIN PGP SIGNED MESSAGE-----
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>>
>> On Thu, 11 Dec 2008, Allan Cassaro wrote:
>>
>> On Thu, 11 Dec 2008, Allan Cassaro wrote:
>>
>>> I don´t have SELinux, or any type or hardening... The ulimit (when
>>> logged with dovecot user) is "unlimited"...
>>
>> Yes, but when Dovecot is spawned as service, the user dovecot does not log
>> in (through PAM anyway to have pam_limits invoked), therefore I assume
>> that limits.conf does not take effect.
>>
>>> Dovecot ran with a lot of proccess here, something about 800~900 imap
>>> proccess and 5~10 login-proccess to 300~400 simultaneous users...
>>
>> Hmm, I do remember something similiar when the new students arrived and
>> the number of simultaneous logins increased above some limit.
>> I added the ulimit command to init.d.
>
> After our conversation, I made some tests:
> 1) Adding this line to /etc/pam.d/common-session (Debian system)
>
> session required pam_limits.so
>
> # cat /etc/security/limits.conf
> dovecot         hard    nofile          2048
> dovecot         soft    nofile          2048
>
> The limits.conf is respected now.
> # su -c 'ulimit -n' dovecot
> 2048  (The value of limits.conf)
> (no login)
>
> # /etc/init.d/dovecot restart
> Warning: fd limit 1024 is lower than what Dovecot can use under full
> load (more than 1456). Either grow the limit or change
> login_max_processes_count and max_mail_processes settings
>
> (Problem persists)
>
> 2) Change the ulimit for root user (as you saw):
> # ulimit -n 2048
>
> # /etc/init.d/dovecot restart
> (no errors)
>
> # cat /etc/security/limits.conf
> dovecot         hard    nofile          2048
> dovecot         soft    nofile          2048
> root         hard    nofile          2048
> root         soft    nofile          2048
>
> So, I think that dovecot uses the limit from the "root" user, not dovecot...
> Now I will wait 20 minutes and see what happens :D
>
> Hooo.. another (ugly) think:
> When imap crashes, the antispam plugin don't erase the
> /tmp/antispam-plugin-XXXXX dir (obviously). So this is possibly to
> "delay" or avoid creation of temp dirs?
>

Hi Steffen,

after some others tests, I don't have problem with file descriptors
any more, but the plugin make the imap proccess dies with segfault
yet...
How can I help more to find this issue?

Regards.