January 2026 - dovecot

Putting a file in a shared namespace causes Panic in quota.c
by Christopher V. 06 Jan '26

06 Jan '26

Dear all, I guess I found a bug. I'm currently testing a migration of my Debian based dovecot bare metal installation from 2.3.19 --> 2.4.1 I'm using shared mailboxes. My understanding from the documentation is: "Quota plugin considers shared namespaces against owner's quota" and "The quota limits are also taken from the userdb." The following setup leads to a "Panic: file quota.c": * Quota is defined per-user and defined in a MySQL Database (and looked up as part of userdb) * User A shares directory "Inbox/teilemich" with user B. * User B has full access rights (details see below) * User A has a quota of 100MB - currently using 60% * User B has a quota of 4GB - currently using 550MB * User A puts mail xyz in the shared directory --> works * User B puts mail abc in the shared directory --> error message (see below) and mail is not stored. Defining the following not-overwritable global quota > 550 MB eliminates the error message. Defining a global quota < 550 MB still leads to the error message. quota "User quota" { storage_size = 560M storage_grace = 10M } Defining an overwritable global quota that is > 550 MB still leads to the error message. quota_storage_size = 560M quota "User quota" { storage_grace = 10M } Can you please check, if this is a bug? If you need some details I'm happy to provide it. Also - I would be very grateful for a workaround / fix. Thanks for all the effort & Best regards, Christopher ----------------------------------------------------- Detailed error message: ==================== Jan 04 17:27:25 <Servername> dovecot[135430]: imap(test@<Servername>.de)<135441><JJetaZJH7O1P12UP>: Panic: file quota.c: line 512 (quota_root_is_visible): assertion failed: (box->list->ns->type == MAIL_NAMESPACE_TYPE_SHARED) Jan 04 17:27:25 <Servername> dovecot[135430]: imap(test@<Servername>.de)<135441><JJetaZJH7O1P12UP>: Error: Raw backtrace: #1 [unw_get_proc_name() failed: -10] -> #2 [unw_get_proc_name() failed: -10] -> #3 i_panic[0x7fa1b4c655e6] -> #4 [unw_get_proc_name() failed: -10] -> #5 [unw_get_proc_name() failed: -10] -> #6 quota_test_alloc[0x7fa1b45a7850] -> #7 quota_try_alloc[0x7fa1b45aa4e0] -> #8 [unw_get_proc_name() failed: -10] -> #9 mailbox_save_finish[0x7fa1b508c7f0] -> #10 mail_storage_copy[0x7fa1b507e670] -> #11 [unw_get_proc_name() failed: -10] -> #12 [unw_get_proc_name() failed: -10] -> #13 [unw_get_proc_name() failed: -10] -> #14 [unw_get_proc_name() failed: -10] -> #15 [unw_get_proc_name() failed: -10] -> #16 mailbox_move[0x7fa1b508cc10] -> #17 [unw_get_proc_name() failed: -10] -> #18 command_exec[0x55da1ef57080] -> #19 [unw_get_proc_name() failed: -10] -> #20 [unw_get_proc_name() failed: -10] -> #21 [unw_get_proc_name() failed: -10] -> #22 client_handle_input[0x55da1ef5d990] -> #23 client_input[0x55da1ef5ded0] -> #24 io_loop_call_io[0x7fa1b4d51710] -> #25 io_loop_handler_run_internal[0x7fa1b4d534b0] -> #26 io_loop_handler_run[0x7fa1b4d53640] -> #27 io_loop_run[0x7fa1b4d53820] -> #28 master_service_run[0x7fa1b4ca6330] -> #29 main[0x55da1ef48880] -> #30 [unw_get_proc_name() failed: -10] -> #31 __libc_start_main[0x7fa1b4e52ce0] -> #32 _start[0x55da1ef48f30] Jan 04 17:27:25 <Servername> dovecot[135430]: imap(test@<Servername>.de)<135441><JJetaZJH7O1P12UP>: Fatal: master: service(imap): child 135441 killed with signal 6 (core dumps disabled - https://dovecot.org/bugreport.html#coredumps) Output of "doveadm acl get -A inbox/teilemich": ======================================= Username ID Global Rights <user A> user=<user B> admin create delete expunge insert lookup post read write write-deleted write-seen Output of "doveconf -a": ==================== # 2.4.1-4 (7d8c0e5759): /etc/dovecot/dovecot.conf # Pigeonhole version 2.4.1-4 (0a86619f) # OS: Linux 6.12.57+deb13-cloud-amd64 x86_64 Debian 13.2 ext4 # Hostname: <Servername> # 4 default setting changes since version 2.4.0 dovecot_config_version = 2.4.0 # NOTE: Send doveconf -n output instead when asking for help. acl_cache_ttl = 30 secs acl_defaults_from_inbox = no acl_driver = vfile acl_global_path = acl_globals_only = no acl_groups = acl_id = acl_ignore = no acl_rights = acl_user = %{master_user} apparmor_hats = auth_allow_cleartext = no auth_allow_weak_schemes = no auth_anonymous_username = anonymous auth_cache_negative_ttl = 180 seconds auth_cache_size = 1024 auth_cache_ttl = 180 seconds auth_cache_verify_password_with_worker = no auth_debug = no auth_debug_passwords = no auth_default_domain = <servername> auth_failure_delay = 2 secs auth_gssapi_hostname = auth_internal_failure_delay = 2 secs auth_krb5_keytab = auth_master_user_separator = auth_mechanisms = plain login auth_policy_check_after_auth = yes auth_policy_check_before_auth = yes auth_policy_hash_mech = sha256 auth_policy_hash_nonce = auth_policy_log_only = no auth_policy_reject_on_fail = no auth_policy_report_after_auth = yes auth_policy_request_attributes = auth_policy_server_api_header = auth_policy_server_url = auth_proxy_self = auth_realms = auth_socket_path = auth-userdb auth_ssl_require_client_cert = no auth_ssl_username_from_cert = no auth_use_winbind = no auth_username_chars = abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@ auth_username_format = %{user|lower} auth_verbose = no auth_verbose_passwords = no auth_winbind_helper_path = /usr/bin/ntlm_auth charset_aliases = compress_bz2_block_size_100k = 9 compress_deflate_level = 6 compress_gz_level = 6 compress_zstd_level = 3 crypt_acl_require_secure_key_sharing = no crypt_global_public_key_file = crypt_private_key_file = crypt_private_key_name = crypt_private_key_password = crypt_user_key_curve = crypt_user_key_password = crypt_user_key_require_encrypted = no crypt_write_algorithm = aes-256-gcm-sha256 debug_log_path = default_client_limit = 1000 default_idle_kill_interval = 1 mins default_internal_group = dovecot default_internal_user = dovecot default_login_user = dovenull default_process_limit = 100 default_vsz_limit = 256 M deliver_log_format = msgid=%{msgid}: %{message} dict_driver = dict_file_lock_method = dotlock dict_file_path = dict_map_expire_field = dict_map_key_field_name = dict_map_key_field_type = string dict_map_key_field_value = dict_map_ldap_filter = dict_map_pattern = dict_map_sql_table = dict_map_username_field = dict_map_value = dict_map_value_field_name = dict_map_value_field_type = string dict_name = dict_proxy_idle_timeout = 0 dict_proxy_name = dict_proxy_slow_warn = 5 secs dict_proxy_socket_path = dict dotlock_use_excl = yes doveadm_allowed_commands = doveadm_api_key = doveadm_password = doveadm_port = 0 doveadm_socket_path = doveadm-server doveadm_ssl = no doveadm_username = doveadm doveadm_worker_count = 0 dovecot_storage_version = 2.4.0 dsync_alt_char = _ dsync_commit_msgs_interval = 100 dsync_features = dsync_remote_cmd = ssh -l%{login} %{host} doveadm dsync-server -u%{user} -U event_exporter_driver = log event_exporter_file_path = event_exporter_format = event_exporter_http_post_url = event_exporter_name = event_exporter_time_format = rfc3339 event_exporter_unix_connect_timeout = 250 ms event_exporter_unix_path = execute_args = execute_driver = unix execute_fork_path = execute_name = execute_tcp_host = execute_tcp_port = 0 execute_unix_socket_path = fifo_listener_group = fifo_listener_mode = 0600 fifo_listener_path = fifo_listener_type = fifo_listener_user = first_valid_gid = 1 first_valid_uid = 500 fs_compress_read_plain_fallback = no fs_compress_write_method = fs_crypt_read_plain_fallback = no fs_dict_value_encoding = raw fs_driver = fs_name = fs_posix_accurate_mtime = no fs_posix_fsync = yes fs_posix_lock_method = flock fs_posix_mode = 0600 fs_posix_prefix = fs_randomfail_ops = fs_sis_queue_path = fts_autoindex = yes fts_autoindex_max_recent_msgs = 999 fts_decoder_driver = fts_decoder_script_socket_path = fts_decoder_tika_url = fts_driver = fts_flatcurve_commit_limit = 500 fts_flatcurve_min_term_size = 2 fts_flatcurve_optimize_limit = 10 fts_flatcurve_rotate_count = 5000 fts_flatcurve_rotate_time = 5 secs fts_flatcurve_substring_search = no fts_header_excludes = fts_header_includes = fts_message_max_size = unlimited fts_search = yes fts_search_add_missing = yes fts_search_read_fallback = yes fts_search_timeout = 30 secs haproxy_timeout = 3 secs haproxy_trusted_networks = hostname = http_client_connect_timeout = 0 http_client_delete_request_max_attempts = 0 http_client_delete_request_timeout = 0 http_client_max_connect_attempts = 0 http_client_max_idle_time = 0 http_client_max_parallel_connections = 1 http_client_max_pipelined_requests = 1 http_client_proxy_password = http_client_proxy_socket_path = http_client_proxy_ssl_tunnel = yes http_client_proxy_url = http_client_proxy_username = http_client_rawlog_dir = http_client_read_request_max_attempts = 0 http_client_read_request_timeout = 0 http_client_request_absolute_timeout = 0 http_client_request_max_attempts = 1 http_client_request_max_redirects = 0 http_client_request_timeout = 1 mins http_client_write_request_max_attempts = 0 http_client_write_request_timeout = 0 http_server_max_client_idle_time = 0 http_server_max_pipelined_requests = 1 http_server_rawlog_dir = imap_acl_allow_anyone = no imap_capability = imap_client_workarounds = imap_fetch_failure = disconnect-immediately imap_hibernate_timeout = 5s imap_id_retain = no imap_id_send = imap_literal_minus = no imap_logout_format = in=%{input} out=%{output} deleted=%{deleted} expunged=%{expunged} trashed=%{trashed} hdr_count=%{fetch_hdr_count} hdr_bytes=%{fetch_hdr_bytes} body_count=%{fetch_body_count} body_bytes=%{fetch_body_bytes} imap_metadata = no imap_urlauth_host = imap_urlauth_logout_format = in=%{input} out=%{output} imap_urlauth_port = 143 imap_urlauth_stream_user = imap_urlauth_submit_user = imapc_cmd_timeout = 5 mins imapc_connection_retry_count = 1 imapc_connection_retry_interval = 1 secs imapc_connection_timeout_interval = 30 secs imapc_features = imapc_host = imapc_list_prefix = imapc_master_user = imapc_max_idle_time = 29 mins imapc_max_line_length = unlimited imapc_password = imapc_port = 143 imapc_rawlog_dir = imapc_sasl_mechanisms = imapc_ssl = no imapc_user = %{owner_user} imapsieve_expunge_discarded = no imapsieve_from_name = imapsieve_url = import_environment = inet_listener_haproxy = no inet_listener_name = inet_listener_port = 0 inet_listener_reuse_port = no inet_listener_ssl = no inet_listener_type = info_log_path = instance_name = dovecot language_default = no language_filter_normalizer_icu_id = Any-Lower; NFKD; [: Nonspacing Mark :] Remove; NFC; [\x20] Remove language_filter_stopwords_dir = /usr/share/dovecot/stopwords language_filters = normalizer-icu snowball stopwords language_name = language_tokenizer_address_token_maxlen = 250 language_tokenizer_generic_algorithm = simple language_tokenizer_generic_explicit_prefix = no language_tokenizer_generic_token_maxlen = 30 language_tokenizer_generic_wb5a = no language_tokenizers = generic email-address last_login_key = # hidden, use -P to show it last_login_precision = s last_valid_gid = 0 last_valid_uid = 0 lazy_expunge_mailbox = lazy_expunge_only_last_instance = no lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes lda_original_recipient_header = X-Original-To ldap_auth_dn = ldap_auth_dn_password = ldap_auth_sasl_authz_id = ldap_auth_sasl_mechanisms = ldap_auth_sasl_realm = ldap_base = ldap_debug_level = 0 ldap_deref = never ldap_max_idle_time = 0 ldap_scope = subtree ldap_starttls = no ldap_timeout = 30 secs ldap_uris = ldap_version = 3 listen = lmtp_add_received_header = yes lmtp_client_workarounds = lmtp_hdr_delivery_address = final lmtp_proxy = no lmtp_proxy_rawlog_dir = lmtp_rawlog_dir = lmtp_rcpt_check_quota = no lmtp_save_to_detail_mailbox = no lmtp_user_concurrency_limit = 0 lock_method = fcntl log_core_filter = log_debug = log_path = syslog log_timestamp = "%b %d %H:%M:%S " login_log_format = %{message}: %{elements} login_log_format_elements = user=<%{user}> method=%{mechanism} rip=%{remote_ip} lip=%{local_ip} mpid=%{mail_pid} %{secured} session=<%{session}> login_plugin_dir = /usr/lib/dovecot/modules/login login_plugins = login_proxy_max_disconnect_delay = 0 login_proxy_max_reconnects = 3 login_proxy_notify_path = proxy-notify login_proxy_rawlog_dir = login_proxy_timeout = 30 secs login_socket_path = login_source_ips = login_trusted_networks = lua_file = lua_settings = mail_access_groups = mail_alt_path = mail_always_cache_fields = mail_attachment_detection_options = mail_cache_fields = mail_chroot = mail_compress_write_method = mail_control_path = mail_debug = no mail_driver = Maildir mail_ext_attachment_min_size = 128 k mail_ext_attachment_path = mail_fsync = optimized mail_full_filesystem_access = no mail_gid = vmail mail_home = /var/spool/dovecot/%{user|domain}/%{user|username}/home mail_inbox_path = mail_index_path = mail_index_private_path = mail_log_cached_only = no mail_log_events = mail_log_fields = mail_log_prefix = "%{service}(%{user})<%{process:pid}><%{session}>: " mail_max_lock_timeout = 0 mail_max_userip_connections = 10 mail_never_cache_fields = mail_nfs_index = no mail_nfs_storage = no mail_path = /var/spool/dovecot/%{user|domain}/%{user|username}/mail mail_plugin_dir = /usr/lib/dovecot/modules mail_plugins { acl = yes quota = yes fts = yes fts_flatcurve = yes quota_clone = yes } mail_prefetch_count = 0 mail_privileged_group = mail mail_server_admin = mailto:admin@<servername> mail_server_comment = mail_shared_explicit_inbox = no mail_sort_max_read_count = 0 mail_temp_dir = /tmp mail_temp_scan_interval = 1 weeks mail_uid = vmail mail_utf8_extensions = no mail_volatile_path = mail_vsize_bg_after_count = 0 mailbox_auto = no mailbox_autoexpunge = 0 mailbox_autoexpunge_max_mails = 0 mailbox_comment = mailbox_directory_name_legacy = yes mailbox_list_index = yes mailbox_list_index_include_inbox = no mailbox_list_index_prefix = dovecot.list.index mailbox_list_index_very_dirty_syncs = no mailbox_list_layout = fs mailbox_list_storage_escape_char = mailbox_list_visible_escape_char = mailbox_name = mailbox_notify_status = no mailbox_special_use = maildir_broken_filename_sizes = no maildir_copy_with_hardlinks = yes maildir_empty_new = no maildir_stat_dirs = no maildir_very_dirty_syncs = no managesieve_client_workarounds = managesieve_implementation_string = Dovecot Pigeonhole managesieve_logout_format = bytes=%{input}/%{output} managesieve_max_compile_errors = 5 managesieve_max_line_length = 64 k managesieve_notify_capability = managesieve_sieve_capability = mbox_dirty_syncs = yes mbox_dotlock_change_timeout = 2 mins mbox_lazy_writes = yes mbox_lock_timeout = 5 mins mbox_read_locks = mbox_very_dirty_syncs = no mbox_write_locks = mdbox_preallocate_space = no mdbox_rotate_interval = 0 mdbox_rotate_size = 10 M metric_description = metric_exporter = metric_exporter_include = metric_fields = metric_filter = metric_group_by_field = metric_group_by_method_discrete_modifier = metric_group_by_method_exponential_base = 10 metric_group_by_method_exponential_max_magnitude = 0 metric_group_by_method_exponential_min_magnitude = 0 metric_group_by_method_linear_max = 0 metric_group_by_method_linear_min = 0 metric_group_by_method_linear_step = 0 metric_group_by_method_method = discrete metric_name = mmap_disable = no mysql_client_flags = 0 mysql_connect_timeout = 5 secs mysql_connection_limit = 5 mysql_dbname = mysql_host = mysql_option_file = mysql_option_group = client mysql_password = mysql_port = 0 mysql_read_timeout = 30 secs mysql_ssl = no mysql_user = mysql_write_timeout = 30 secs namespace_alias_for = namespace_disabled = no namespace_hidden = no namespace_ignore_on_failure = no namespace_inbox = no namespace_list = yes namespace_name = namespace_order = 0 namespace_prefix = namespace_separator = namespace_subscriptions = yes namespace_type = private notify_status_value = {"messages":%{messages},"unseen":%{unseen}} oauth2_active_attribute = oauth2_active_value = oauth2_client_id = oauth2_client_secret = oauth2_fields = oauth2_force_introspection = no oauth2_grant_url = oauth2_introspection_mode = oauth2_introspection_url = oauth2_issuers = oauth2_openid_configuration_url = oauth2_scope = oauth2_send_auth_headers = no oauth2_tokeninfo_url = oauth2_use_worker_with_mech = no oauth2_username_attribute = email oauth2_username_validation_format = %{user} passdb_default_password_scheme = PLAIN passdb_deny = no passdb_driver = passdb_fields = passdb_fields_import_all = yes passdb_master = no passdb_mechanisms_filter = passdb_name = passdb_pam_failure_show_msg = no passdb_pam_max_requests = 100 passdb_pam_service_name = dovecot passdb_pam_session = no passdb_pam_setcred = no passdb_result_failure = continue passdb_result_internalfail = continue passdb_result_success = return-ok passdb_skip = never passdb_sql_query = passdb_sql_update_query = passdb_static_password = passdb_use_cache = yes passdb_use_worker = no passdb_username_filter = passwd_file_path = pop3_client_workarounds = pop3_delete_type = default pop3_deleted_flag = pop3_enable_last = no pop3_fast_size_lookups = no pop3_lock_session = no pop3_logout_format = top=%{top_count}/%{top_bytes}, retr=%{retr_count}/%{retr_bytes}, del=%{deleted_count}/%{deleted_bytes}, size=%{message_bytes} pop3_migration_all_mailboxes = no pop3_migration_ignore_extra_uidls = no pop3_migration_ignore_missing_uidls = no pop3_migration_mailbox = pop3_migration_skip_size_check = no pop3_migration_skip_uidl_cache = no pop3_no_flag_updates = no pop3_reuse_xuidl = no pop3_save_uidl = no pop3_uidl_duplicates = allow pop3_uidl_format = %{uid | hex(8)}%{uidvalidity | hex(8)} pop3c_features = pop3c_host = pop3c_master_user = pop3c_password = pop3c_port = 110 pop3c_quick_received_date = no pop3c_rawlog_dir = pop3c_ssl = no pop3c_ssl_verify = yes pop3c_user = %{user} postmaster_address = postmaster@%{user|domain|default(hostname)} process_shutdown_filter = protocols { imap = yes lmtp = yes sieve = yes } push_notification_driver = push_notification_name = push_notification_ox_cache_ttl = 1 mins push_notification_ox_url = push_notification_ox_user_from_metadata = no quota_clone_unset = no quota_driver = count quota_enforce = yes quota_exceeded_message = Quota exceeded (mailbox for user is full) quota_fs_message_limit = no quota_fs_mount_path = quota_fs_type = any quota_full_tempfail = yes quota_hidden = no quota_ignore = no quota_ignore_unlimited = no quota_imapc_mailbox_name = INBOX quota_imapc_root_name = quota_mail_size = unlimited quota_mailbox_count = unlimited quota_mailbox_message_count = unlimited quota_message_count = unlimited quota_message_percentage = 100 quota_name = quota_over_status_current = quota_over_status_lazy_check = no quota_over_status_mask = quota_status_nouser = REJECT Unknown user quota_status_overquota = 554 5.2.2 %{error} quota_status_success = OK quota_status_toolarge = quota_storage_extra = 0 quota_storage_grace = 10 M quota_storage_percentage = 100 quota_storage_size = 50M quota_warning_name = quota_warning_resource = storage quota_warning_threshold = over rawlog_dir = recipient_delimiter = + redis_db_id = 0 redis_expire = 0 redis_host = 127.0.0.1 redis_key_prefix = redis_password = redis_port = 6379 redis_request_timeout = 30 secs redis_socket_path = rejection_reason = Your message to <%{to}> was automatically rejected:%{literal('\r\n')}%{reason} rejection_subject = Rejected: %{subject} sendmail_path = /usr/sbin/sendmail service_chroot = service_client_limit = 0 service_drop_priv_before_exec = no service_executable = service_extra_groups = service_group = service_idle_kill_interval = 0 service_name = service_privileged_group = service_process_limit = 0 service_process_min_avail = 0 service_protocol = service_restart_request_count = unlimited service_type = service_user = service_vsz_limit = 0 shutdown_clients = yes sieve_duplicate_default_period = 12 hours sieve_duplicate_max_period = 2 days sieve_editheader_header_forbid_add = no sieve_editheader_header_forbid_delete = no sieve_editheader_header_name = sieve_editheader_max_header_size = 2 k sieve_enabled = yes sieve_environment = sieve_execute_bin_dir = sieve_execute_exec_timeout = 10 secs sieve_execute_input_eol = crlf sieve_execute_socket_dir = sieve_extensions { fileinto = yes reject = yes envelope = yes encoded-character = yes vacation = yes subaddress = yes comparator-i;ascii-numeric = yes relational = yes regex = yes imap4flags = yes copy = yes include = yes body = yes variables = yes enotify = yes environment = yes mailbox = yes date = yes index = yes ihave = yes duplicate = yes mime = yes foreverypart = yes extracttext = yes editheader = no spamtest = yes mboxmetadata = yes virustest = yes } sieve_filter_bin_dir = sieve_filter_exec_timeout = 10 secs sieve_filter_input_eol = crlf sieve_filter_socket_dir = sieve_global_extensions = sieve_implicit_extensions = sieve_include_max_includes = 255 sieve_include_max_nesting_depth = 10 sieve_max_actions = 32 sieve_max_cpu_time = 0 sieve_max_redirects = 4 sieve_max_script_size = 1 M sieve_notify_mailto_envelope_from = sieve_pipe_bin_dir = sieve_pipe_exec_timeout = 10 secs sieve_pipe_input_eol = crlf sieve_pipe_socket_dir = sieve_plugin_dir = /usr/lib/dovecot/modules/sieve sieve_plugins = sieve_quota_script_count = 0 sieve_quota_storage_size = 0 sieve_redirect_duplicate_period = 43200 sieve_redirect_envelope_from = sieve_report_from = sieve_resource_usage_timeout = 1 hours sieve_script_active_path = sieve_script_bin_path = sieve_script_cause = sieve_script_driver = file sieve_script_ldap_filter = sieve_script_ldap_modified_attribute = sieve_script_ldap_script_attribute = sieve_script_name = sieve_script_path = sieve_script_precedence = unlimited sieve_script_storage = sieve_script_type = personal sieve_spamtest_score_max_header = sieve_spamtest_score_max_value = sieve_spamtest_status_header = sieve_spamtest_status_type = score sieve_spamtest_text_value = sieve_trace_addresses = no sieve_trace_debug = no sieve_trace_dir = sieve_trace_level = none sieve_user_email = sieve_user_log_path = sieve_vacation_check_recipient = yes sieve_vacation_default_period = 1 weeks sieve_vacation_default_subject = sieve_vacation_default_subject_template = sieve_vacation_max_period = 60 days sieve_vacation_min_period = 1 days sieve_vacation_send_from_recipient = no sieve_vacation_to_header_ignore_envelope = no sieve_vacation_use_original_recipient = no sieve_variables_max_scope_count = 255 sieve_variables_max_value_size = 4 k sieve_virustest_score_max_header = sieve_virustest_score_max_value = sieve_virustest_status_header = sieve_virustest_status_type = score sieve_virustest_text_value = sql_driver = mysql ssl = yes ssl_cipher_list = ALL:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@STRENGTH:!AECDH:!RC4-SHA:!SHA1 ssl_cipher_suites = ssl_client_ca_dir = ssl_client_ca_file = ssl_client_cert_file = ssl_client_key_file = ssl_client_key_password = ssl_client_require_valid_cert = yes ssl_crypto_device = ssl_curve_list = ssl_min_protocol = TLSv1.2 ssl_options = ssl_server_alt_cert_file = ssl_server_alt_key_file = ssl_server_ca_file = ssl_server_cert_file = ssl_server_cert_username_field = commonName ssl_server_dh_file = ssl_server_key_file = ssl_server_key_password = ssl_server_prefer_ciphers = client ssl_server_request_client_cert = no ssl_server_require_crl = yes stats_writer_socket_path = stats-writer submission_add_received_header = yes submission_backend_capabilities = submission_client_workarounds = submission_host = submission_logout_format = in=%{input} out=%{output} submission_max_mail_size = 0 submission_max_recipients = 0 submission_relay_command_timeout = 5 mins submission_relay_connect_timeout = 30 secs submission_relay_host = submission_relay_master_user = submission_relay_max_idle_time = 29 mins submission_relay_password = submission_relay_port = 25 submission_relay_rawlog_dir = submission_relay_ssl = no submission_relay_ssl_verify = yes submission_relay_trusted = no submission_relay_user = submission_ssl = no submission_timeout = 30 secs syslog_facility = mail textcat_config_path = trash_priority = 0 unix_listener_group = unix_listener_mode = 0600 unix_listener_path = unix_listener_type = unix_listener_user = userdb_driver = userdb_fields = userdb_fields_import_all = yes userdb_name = userdb_result_failure = continue userdb_result_internalfail = continue userdb_result_success = return-ok userdb_skip = never userdb_sql_iterate_query = userdb_sql_query = userdb_static_allow_all_users = no userdb_use_cache = yes userdb_use_worker = no valid_chroot_dirs = verbose_proctitle = no version_ignore = no virtual_max_open_mailboxes = 64 welcome_wait = no mysql localhost { dbname = sys_mail password = # hidden, use -P to show it ssl = no user = sys_dovecot } userdb sql { iterate_query = SELECT username AS user FROM mailbox query = SELECT CONCAT('/var/spool/dovecot/',maildir,'mail') AS mail_path, CONCAT('/var/spool/dovecot/',maildir) AS home, 5000 AS uid, 5000 AS gid, CONCAT(quota,'B') AS quota_storage_size FROM mailbox WHERE username = '%{user|lower}' } passdb pam { default_password_scheme = CRYPT service_name = dovecot skip = authenticated } namespace inbox { inbox = yes separator = / type = private mailbox Drafts { auto = subscribe special_use = "\\Drafts" } mailbox Junk { auto = subscribe special_use = "\\Junk" } mailbox Trash { auto = subscribe special_use = "\\Trash" quota_storage_percentage = 110 } mailbox Sent { auto = subscribe special_use = "\\Sent" } mailbox "Sent Messages" { auto = no special_use = "\\Sent" } } namespace shared { mail_driver = maildir mail_index_path = /var/spool/dovecot/%{user|domain}/%{user|username}/sharedmailboxes/%{owner_user|domain}/%{owner_user|username} mail_path = /var/spool/dovecot/%{owner_user|domain}/%{owner_user|username}/mail list = children prefix = shared/$user/ separator = / type = shared } service imap-login { inet_listener imap { listen = 127.0.0.1 } inet_listener imaps { } } service lmtp { unix_listener lmtp { } } service auth { unix_listener auth-userdb { group = vmail mode = 0600 user = vmail } unix_listener /var/spool/postfix/private/auth { group = mail mode = 0666 user = postfix } } service auth-worker { user = $SET:default_internal_user } service dict { unix_listener dict { group = vmail mode = 0600 user = vmail } } service imap-hibernate { unix_listener imap-hibernate { group = vmail mode = 0660 user = dovecot } } service imap { unix_listener imap-master { user = dovecot } } ssl_server { cert_file = /etc/letsencrypt/live/<Servername>.de/fullchain.pem dh_file = /etc/dovecot/dh.pem key_file = /etc/letsencrypt/live/<Servername>.de/privkey.pem prefer_ciphers = server } protocol lda { mail_plugins { sieve = yes } } protocol imap { mail_max_userip_connections = 30 mail_plugins { imap_sieve = yes imap_quota = yes imap_acl = yes imap_zlib = no } } protocol lmtp { auth_username_format = %{user | username | lower} mail_plugins { sieve = yes } } service managesieve-login { process_min_avail = 1 restart_request_count = 1 vsz_limit = 64M inet_listener sieve { port = 4190 listen = 127.0.0.1 } } service managesieve { process_limit = 1024 } protocol sieve { mail_max_userip_connections = 10 managesieve_max_line_length = 65536 } dict_server { dict mysql { driver = sql hostname = localhost sql_driver = mysql ssl = no dict_map priv/quota/storage { sql_table = quota2 username_field = username dict_map_value_field bytes { type = uint } } dict_map priv/quota/messages { sql_table = quota2 username_field = username dict_map_value_field messages { type = uint } } dict_map "shared/shared-boxes/user/$to/$from" { sql_table = user_shares dict_map_value_field dummy { } dict_map_key_field from_user { value = $from } dict_map_key_field to_user { value = $to } } dict_map "shared/shared-boxes/anyone/$from" { sql_table = anyone_shares dict_map_value_field dummy { } dict_map_key_field from_user { value = $from } } } } acl_sharing_map { dict proxy { name = mysql } } language en { filters = lowercase snowball english-possessive stopwords } language de { default = yes filters = snowball stopwords normalizer-icu } fts flatcurve { substring_search = yes } quota "User quota" { driver = count storage_grace = 10M quota_warning warn-100 { quota_storage_percentage = 100 execute quota-full { args = 100 %{user} } } quota_warning warn-95 { quota_storage_percentage = 95 execute quota-warning { args = 95 %{user} } } quota_warning warn-80 { quota_storage_percentage = 80 execute quota-warning { args = 80 %{user} } } } service quota-warning { executable = script /usr/local/bin/quota-warning.sh unix_listener quota-warning { user = vmail } } service quota-full { executable = script /usr/local/bin/quota-warning-full.sh unix_listener quota-full { user = vmail } } quota_clone { dict proxy { name = mysql } } sieve_script personal { active_path = /var/spool/dovecot/%{user|domain}/%{user|username}/sieve/.dovecot.sieve driver = file path = /var/spool/dovecot/%{user|domain}/%{user|username}/sieve } sieve_script default { driver = file name = default path = /var/spool/dovecot/sieve/default.sieve type = default } service indexer-worker { executable = /usr/bin/nice -n 10 /usr/lib/dovecot/indexer-worker process_limit = 1 user = vmail }

2 2

time diff miscalculation on 32-bit systems
by Andy Spiegl 06 Jan '26

06 Jan '26

Dear dovecot team, I believe I found a bug in dovecot on 32-bit systems. Dovecot version: 1:2.4.1+dfsg1-6 (Architecture: i386) Operating system: Linux lar 6.13.7-64+ #1 SMP PREEMPT Fri Mar 21 08:33:47 MEZ 2025 x86_64 GNU/Linux Distributor ID: Debian Description: Debian GNU/Linux 13 (trixie) Release: 13 Codename: trixie * What led up to the situation? Upgrade from 2.3.21.1 to 1:2.4.1 * What was the outcome of this action? Logs are flooded with messages "Warning: Time moved forward" * Problem Description: The function io_loop_get_wait_time in ioloop.c contains the line: ioloop->next_max_time.tv_sec = (1ULL << (TIME_T_MAX_BITS-1)) - 1; On 32-bit systems TIME_T_MAX_BITS is 31 such that the result of this calculation is 1073741823. Far from the intended "infinity" and even before "now". This leads to problems in the function io_loop_handle_timeouts_real: the calculation of the time difference between now and next_max_time is then something like -693628953 seconds which confuses dovecot and floods the logs with these warnings: Jan 02 17:43:43 lmtp(38364): Warning: Time moved forward 693630400.301863 seconds Jan 02 17:43:43 lmtp(38364): Warning: Time moved forward 693630400.304144 seconds Jan 02 17:45:43 lmtp(38364): Warning: Time moved forward 693630520.416053 seconds * Possible solution/workaround ? ioloop->next_max_time.tv_sec = INT_MAX; Thanks for your consideration, Andy

2 1

Missing dovecot-pigeonhole packages in official CE-2.4 repo for RHEL/Rocky Linux 10
by Mateusz Kiczela 06 Jan '26

06 Jan '26

Hello Dovecot Team, I am attempting to install Dovecot 2.4.2 on Rocky Linux 10 (RHEL 10 compatible) using the official repository found at: http://repo.dovecot.org/ce-2.4-latest/rhel/10/RPMS/x86_64/ The Issue: Although the core Dovecot packages (dovecot, dovecot-imapd, etc.) are present, the Pigeonhole (Sieve/ManageSieve) packages are completely missing from the repository index. I have verified this by browsing the directory listing directly. Missing Packages: - dovecot-pigeonhole - dovecot-sieve - dovecot-managesieved Could you please check the build pipeline for RHEL/CentOS/Rocky Linux 10? It appears the Pigeonhole artifacts are not being published, and the base dependencies might need a rebuild against current EL10 libraries. Thank you for your support! Best regards. Mateusz Kiczela Hello Dovecot Team, I am attempting to install Dovecot 2.4.2 on Rocky Linux 10 (RHEL 10 compatible) using the official repository found at: [1]http://repo.dovecot.org/ce-2.4-latest/rhel/10/RPMS/x86_64/ The Issue: Although the core Dovecot packages (dovecot, dovecot-imapd, etc.) are present, the Pigeonhole (Sieve/ManageSieve) packages are completely missing from the repository index. I have verified this by browsing the directory listing directly. Missing Packages: - dovecot-pigeonhole - dovecot-sieve - dovecot-managesieved Could you please check the build pipeline for RHEL/CentOS/Rocky Linux 10? It appears the Pigeonhole artifacts are not being published, and the base dependencies might need a rebuild against current EL10 libraries. Thank you for your support! Best regards. Mateusz Kiczela References Visible links 1. http://repo.dovecot.org/ce-2.4-latest/rhel/10/RPMS/x86_64/

2 3

Getting Dovecot to coredump
by Washington Odhiambo 05 Jan '26

05 Jan '26

Can someone please give simple steps to make dovecot to coredump on Debian 12? After reading this: https://doc.dovecot.org/2.4.2/developers/debugging.html#coredumps - I am still not able to get it to work. I have been running dovecot from git (yes, I know I shouldn't!) until I updated today and then it would be killed by signal 11. I have so far installed the release versions and all is fine, but I'd like to ensure that in the future, I have the coredump working. -- Best regards, Odhiambo WASHINGTON, Nairobi,KE +254 7 3200 0004/+254 7 2274 3223 In an Internet failure case, the #1 suspect is a constant: DNS. "Oh, the cruft.", egrep -v '^$|^.*#' ¯\_(ツ)_/¯ :-) [How to ask smart questions: http://www.catb.org/~esr/faqs/smart-questions.html] Can someone please give simple steps to make dovecot to coredump on Debian 12? After reading this: [1]https://doc.dovecot.org/2.4.2/developers/debugging.html#coredumps - I am still not able to get it to work. I have been running dovecot from git (yes, I know I shouldn't!) until I updated today and then it would be killed by signal 11. I have so far installed the release versions and all is fine, but I'd like to ensure that in the future, I have the coredump working. -- Best regards, Odhiambo WASHINGTON, Nairobi,KE +254 7 3200 0004/+254 7 2274 3223 In an Internet failure case, the #1 suspect is a constant: DNS. "Oh, the cruft.", egrep -v '^$|^.*#' -\_(Tu)_/- :-) [How to ask smart questions: [2]http://www.catb.org/~esr/faqs/smart-questions.html] References Visible links 1. https://doc.dovecot.org/2.4.2/developers/debugging.html#coredumps 2. http://www.catb.org/~esr/faqs/smart-questions.html

2 3

dovecot-2.3.21.1 for Fedora 43
by John Fawcett 04 Jan '26

04 Jan '26

Hi I realize this may seem overly nostalgic, but I was wondering if anyone has successfully got dovecot-2.3.21.1 running on Fedora 43? I'm about to do an upgrade to Fedora 43 and I wanted to avoid doing a simultaneous upgrade to Dovecot 2.4 which is now the distro packaged version, since I have not yet converted my configuration. I managed to compile from source (after taking care of adding -licuuc to the linker flags when linking test-fts-filter). However running test-lib then fails on two tests. test-buffer-istream.c:54: Assert failed: buffer_append_full_file(result, TEST_FILENAME, SIZE_MAX, &error) == BUFFER_APPEND_READ_ERROR test-buffer-istream.c:56: Assert failed: error != NULL && *error != '\0' buffer_append_full_file .............................................. : FAILED and test-data-stack.c:191: Assert failed: a == b data-stack buffer interruption ....................................... : FAILED If instead I use a src rpm like the one from here: https://koji.fedoraproject.org/koji/buildinfo?buildID=2651758 that includes fedora specific patches and try to rebuild it, it builds without the libicuuc issue, but then fails on one (different) test: Error: error:078C0102:common libcrypto routines::passed a null parameter test-hmac.c:275: Assert(#3) failed: memcmp(res->data, vec->okm, vec->okm_len) == 0 hkdf sha256 rfc5869 vectors .......................................... : FAILED My assumption as yet unverified is that the fedora specific patches are avoiding the two test errors iwhen using the unpatched source, but contribute to the error produced when using the patched source, though my test did not rule out environment differences between these two tests. John

2 2

Failed tests in core & pigeonhole git HEAD
by Patrick 02 Jan '26

02 Jan '26

Hi, Happy New Year! During make check of core git rev 6d6724bd529493c448d5aa02e70aee9aaff4f2c3 (from github) with mock a test fails with: <mock-chroot> sh-5.3# more test-suite.log ============================================ Dovecot 2.4.3: src/imap/test-suite.log ============================================ # TOTAL: 2 # PASS: 1 # SKIP: 0 # XFAIL: 0 # FAIL: 1 # XPASS: 0 # ERROR: 0 System information (uname -a): Linux 6.17.12-300.fc43.x86_64 #1 SMP PREEMPT_DYNAMIC Sat Dec 13 05:06:24 UTC 2025 x8 6_64 Distribution information (/etc/os-release): NAME="Fedora Linux" VERSION="43 (Forty Three)" RELEASE_TYPE=stable ID=fedora VERSION_ID=43 VERSION_CODENAME="" PRETTY_NAME="Fedora Linux 43 (Forty Three)" ANSI_COLOR="0;38;2;60;110;180" .. contents:: :depth: 2 FAIL: test-imap-client-hibernate ================================ imap client hibernate: non-IDLE ...................................... : ok test-common.c:300: Assert failed: suppress == TRUE test-imap-client-hibernate: Error: Couldn't hibernate imap client: net_connect_unix(/builddir/build/BUILD/dovecot-2 .4.3-build/dovecot/.test/imap-client-hibernate-130478.fdf4a74f3b5b21f2/imap-hibernate) failed: File name too long imap client hibernate: socket not found .............................. : FAILED test-imap-client-hibernate: Fatal: net_listen_unix(/builddir/build/BUILD/dovecot-2.4.3-build/dovecot/.test/imap-cli ent-hibernate-130478.fdf4a74f3b5b21f2/imap-hibernate) failed: File name too long FAIL test-imap-client-hibernate (exit status: 89) Pigeonhole git rev 7229ac65540889fc3e9658c4623eafc5a9952006 make check shows: make check-local make[1]: Entering directory '/builddir/build/BUILD/dovecot-2.4.3-build/dovecot/dovecot-pigeonhole' rm -rf ./.test make[1]: Leaving directory '/builddir/build/BUILD/dovecot-2.4.3-build/dovecot/dovecot-pigeonhole' testsuite: Fatal: execv(/usr/bin/doveconf) failed: No such file or directory make: *** [Makefile:1280: tests/testsuite.svtest] Error 84 Best, Patrick

1 0