After a recent update of dovecot to 2.2.devel (d81a83b) I started to get errors like that:

Jul 26 07:34:44 mx kernel: pop3[17311]: segfault at 1ee74b0d5 ip 00000001ee74b0d5 sp 00007ffe593dc3c0 error 14 in lib11_trash_plugin.so[ 7f66edce2000+3000] Jul 26 08:11:25 mx dovecot: pop3(xxxxxxxx): Fatal: master: service(pop3): child 17311 killed with signal 11 (core dumps disabled)

My dovecot configuration follows: # 2.2.devel (d81a83b): /etc/dovecot/dovecot.conf # Pigeonhole version 0.4.devel (3f51b82) # OS: Linux 3.16.0-4-amd64 x86_64 Debian 8.5 ext4 auth_default_realm = euct.ru auth_mechanisms = plain login dict { acl = mysql:/etc/dovecot/dovecot-dict-sql.conf.ext quota = mysql:/etc/dovecot/dovecot-dict-sql.conf.ext } lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes listen = * login_greeting = Hello. mail_gid = 5000 mail_location = maildir:/home/vmail/%d/%u mail_max_userip_connections = 25 mail_plugins = " quota trash" mail_uid = 5000 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 index ihave duplicate mime foreverypart extracttext namespace { list = children location = maildir:/home/vmail/%d/%%n:INDEX=/home/vmail/%d/%n/Shared/%%u prefix = Shared/%%u/ separator = / subscriptions = yes type = shared } namespace inbox { inbox = yes list = yes location = mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Junk { auto = subscribe special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { auto = subscribe autoexpunge = 1 weeks special_use = \Trash } prefix = separator = / type = private } passdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { acl = vfile acl_shared_dict = proxy::acl deleted_to_trash_folder = Trash quota = dict:User quota::proxy::quota quota_grace = 50M quota_rule = *:storage=250M quota_rule2 = Trash:storage=+50M quota_warning = storage=95%% quota-warning 95 %u quota_warning2 = storage=80%% quota-warning 80 %u sieve = ~/sieve/.dovecot.sieve sieve_dir = ~/sieve sieve_vacation_default_period = 7d sieve_vacation_max_period = 30d sieve_vacation_min_period = 1d trash = /etc/dovecot/dovecot-trash.conf.ext } postmaster_address = postmaster@euct.ru protocols = " imap sieve pop3" service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } unix_listener auth-userdb { group = dovecot mode = 0666 user = vmail } } service dict { unix_listener dict { group = dovecot mode = 0600 user = vmail } } service imap-login { inet_listener imap { port = 143 } inet_listener imaps { port = 993 ssl = yes } } service pop3-login { inet_listener pop3 { port = 110 } inet_listener pop3s { port = 995 ssl = yes } } service quota-warning { executable = script /usr/local/bin/quota-warning.sh unix_listener quota-warning { user = vmail } user = dovecot } ssl = required ssl_cert = </etc/letsencrypt/live/mail.euct.ru/fullchain.pem ssl_dh_parameters_length = 2048 ssl_key = </etc/letsencrypt/live/mail.euct.ru/privkey.pem ssl_protocols = !SSLv2 !SSLv3 userdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } protocol lda { mail_plugins = " quota trash acl sieve" } protocol imap { mail_plugins = " quota trash quota imap_quota acl imap_acl deleted_to_trash" }