[Dovecot] dovecot segfaults after upgrade

[Thomas Blomenkamp]

Using dovecot on debian oldstable (squeeze) with daily builded repository, 
after an upgrade this morning, dovecot always shows the following error:

2013 Jun 10 11:07:22 mailstore imap(tblomenk): Fatal: master: 
service(imap): child 3016 killed with signal 11 (core dumps disabled)
Jun 10 11:07:22 mailstore kernel: [ 1589.400741] imap[3016]: segfault at 
7fffd9048ff8 ip 00007f91417e2c3b sp 00007fffd9049000 error 6 in 
libdovecot.so.0.0.0[7f9141796000+bc000]

Please notice: I can reproduce the error by trying to access my mailbox 
with alpine or mutt, while alpine only can access my inbox. If I try to 
access my other folders, the error happens. Mutt always closes the 
connection after trying to login. It is a little bit strange because with 
a newer client like roundcube I can access all my folders successfully.

In all kernel error messages it seems that

error 6 in libdovecot.so.0.0.0[7f9141796000+bc000]

is always the same.

Also notice that dovecot is still running, it is just that you cannot 
access other folders than your inbox with pine.

mailstore:~# dovecot --version
2.2.2 (45399357008a)

mailstore:~# dovecot -n
# 2.2.2 (45399357008a): /etc/dovecot/dovecot.conf
doveconf: Warning: service auth { client_limit=1000 } is lower than 
required under max. load (1324)
doveconf: Warning: service anvil { client_limit=1000 } is lower than 
required under max. load (1227)
# OS: Linux 2.6.32-5-amd64 x86_64 Debian 6.0.7
auth_debug = yes
auth_gssapi_hostname = mailstore.math.uni-bielefeld.de
auth_mechanisms = plain login
auth_username_format = %n
auth_verbose = yes
lmtp_save_to_detail_mailbox = yes
log_timestamp = "%Y-%m-%d %H:%M:%S "
login_greeting = Hi, the IMAP Mail-System on 
mailstore.math.uni-bielefeld.de is ready.
login_log_format_elements = user=<%u> method=%m rip=%r lip=%l %c
mail_location = mdbox:~/mdbox
mail_plugins = acl
mail_privileged_group = mail
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope encoded-character 
vacation subaddress comparator-i;ascii-numeric relational regex imap4flags 
copy include variables body enotify environment mailbox date ihave 
spamtest spamtestplus imapflags notify
namespace {
   list = children
   location = mdbox:%%h/mdbox
   prefix = shared/%%u/
   separator = /
   subscriptions = no
   type = shared
}
namespace inbox {
   inbox = yes
   location =
   mailbox Drafts {
     auto = subscribe
     special_use = \Drafts
   }
   mailbox Sent {
     auto = subscribe
     special_use = \Sent
   }
   mailbox Spam {
     auto = subscribe
     special_use = \Junk
   }
   mailbox Trash {
     auto = subscribe
     special_use = \Trash
   }
   prefix =
   separator = /
   type = private
}
passdb {
   args = /etc/dovecot/dovecot-ldap.conf
   driver = ldap
}
plugin {
   acl = vfile
   acl_shared_dict = file:/var/lib/dovecot/shared-mailboxes.db
   mail_log_events = delete undelete expunge copy mailbox_delete 
mailbox_rename
   mail_log_fields = uid box msgid size
   mail_log_group_events = no
   quota = maildir:User quota
   quota_rule = *:storage=0
   sieve = ~/.dovecot.sieve
   sieve_dir = ~/sieve
   sieve_extensions = +imapflags +notify +spamtest +spamtestplus
   sieve_spamtest_max_value = 100
   sieve_spamtest_status_header = X-PMX-Spam: 
\.*Probability=([[:digit:]]+)%+\.*
   sieve_spamtest_status_type = score
}
protocols = imap lmtp sieve
service auth {
   unix_listener auth-master {
     mode = 0600
     user = vmail
   }
   unix_listener auth-userdb {
     user = vmail
   }
   user = root
}
service imap-login {
   inet_listener imap {
     port = 143
   }
   inet_listener imaps {
     port = 0
   }
   process_limit = 1024
   process_min_avail = 10
   service_count = 1
}
service imap {
   process_limit = 1024
}
service lmtp {
   unix_listener /var/spool/postfix/private/dovecot-lmtp {
     group = postfix
     mode = 0660
     user = postfix
   }
}
service managesieve-login {
   inet_listener sieve {
     port = 4190
   }
   service_count = 1
   vsz_limit = 64 M
}
ssl_cert = </etc/dovecot/mailstore_cert_chain.pem
ssl_key = </etc/ssl/private/mcl_key.pem
userdb {
   args = uid=vmail gid=vmail home=/var/vmail_san2/dovecot/%1Lu/%Lu
   driver = static
}
protocol imap {
   mail_plugins = acl imap_acl
}
protocol lmtp {
   mail_plugins = acl sieve
}
protocol sieve {
   mail_max_userip_connections = 50
   managesieve_implementation_string = Dovecot Pigeonhole
   managesieve_logout_format = bytes=%i/%o
   managesieve_max_compile_errors = 5
   managesieve_max_line_length = 65536
}

Regards,

Thomas