[Dovecot] Imap segfault on login with version 2.0.8 & 2.0.11

[Nicholas VonHollen]

Hi Timo,

Thanks for helping me out.  It looks like no matter what I do, changing the executable line doesn't help.  I even changed it to "executable = /bin/false" and it still reports a segfault.  I verified the config with "dovecot -n", stopped using the "-c /etc/dovecot.conf", moved the conf file to the appropriate place, re-verified it, and I still can't affect it.  I assume the crash is happening post-fork, pre-exec, if there is custom code for launching child processes.  Since strace 'fixes' the problem, I'll try to figure it out under gdb, but to be honest, my C debugging skills are very rusty.

Any ideas?

Logs with "executable = /bin/false" (same as before):
...
Apr  7 17:29:04 localhost dovecot: auth: Debug: Module loaded: /usr/lib64/dovecot/auth/libmech_gssapi.so
Apr  7 17:29:04 localhost dovecot: auth: Debug: passwd-file /etc/dovecot-master.passwd: Read 1 users
Apr  7 17:29:04 localhost dovecot: auth: Debug: pam(foo,127.0.0.1): lookup service=system-auth
Apr  7 17:29:05 localhost dovecot: auth: Debug: pam(foo,127.0.0.1): #1/1 style=1 msg=Password: 
Apr  7 17:29:05 localhost dovecot: auth: Debug: client out: OK	1	user=foo
Apr  7 17:29:05 localhost dovecot: master: Error: service(imap): child 9690 killed with signal 11 (core dumps disabled)
Apr  7 17:29:05 localhost dovecot: master: Error: service(imap): command startup failed, throttling
Apr  7 17:29:05 localhost dovecot: imap-login: Error: read(imap) failed: Connection reset by peer
Apr  7 17:29:05 localhost dovecot: imap-login: Internal login failure (pid=9680 id=1) (auth failed, 1 attempts): user=<foo>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, secured
Apr  7 17:29:05 localhost dovecot: auth: Debug: client in: CANCEL	1



Thanks,
Nick



"Timo Sirainen" <tss at iki.fi> said:

> On Wed, 2011-04-06 at 18:53 -0400, Nicholas VonHollen wrote:
> 
>> I'm trying to upgrade/test our configuration files from Dovecot 1.2 to
>> 2.0.11.  I used the Dovecot config convert command, created a RHEL 5
>> x86_64 rpm, and tested it.  I can connect, but once I login, the IMAP
>> service segfaults.  I've also reproduced this on version 2.0.8.
> 
> Try what happens when running imap directly:
> 
> /usr/lib/dovecot/imap -u user at domain
> 
> Does it still crash? If not, you could try if running it via valgrind
> logs anything useful:
> 
> service imap {
>   executable = /usr/bin/valgrind /usr/lib/dovecot/imap
> }
> 
> 
> 


Nick VonHollen
Rackspace Software Developer
Desk: 540-443-2003 (internal 505-2003)
Personal Cell: 757-710-7038