- dovecot - dovecot.org

undocumented changed behavior of 2.4.3 (possible bug report)
by Patrick Cernko 21 Apr '26

21 Apr '26

Hello Dovecot-Devs, hello list, while upgrading my Dovecot 2.4.2 setup to 2.4.3 I observed two instances of changed behavior. I could not find notes about those issues in the corresponding documentation (https://doc.dovecot.org/2.4.3/installation/upgrade/2.4-to-2.4.x.html) or release notes: 1. I had to change userdb_ldap_iterate_filter = (&(objectClass=posixAccount)%{if(protocol,"eq","pop3","(istIsMemberOf=POP3-users)","")}) to userdb_ldap_iterate_filter = (&(objectClass=posixAccount)%{if(protocol,"eq","pop3","(istIsMemberOf=POP3-users)","")|safe) otherwise the characters '()=' in the "true"-case of the condition got somehow "quoted" with escaped ASCII codes, which led to a broken LDAP filter string. Maybe you could add some documentation (in "Upgrading" as well as "Settings Variables") about that? 2. The behavior of sieve matches using ":matches" has changed: Example email (only the relevant header): List-Id: Dovecot Mailing List <dovecot.dovecot.org> Example Sieve script: if header :matches "List-Id" "*<dovecot*.dovecot.org>" { fileinto "dovecot"; } In 2.4.2 (and earlier) the example email matched the condition and got stored in the dovecot folder, while in 2.4.3 the condition does NOT match. As a workaround I added a '*' at the end of the match ("*<dovecot*.dovecot.org>*") to get my mails stored correctly again. Is this changed behavior for Sieve intentional or a bug? In case of a bug, could you please provide a fix? In case of intentional behavior: * Could you please explain the intention? Why was it necessary? * What would be the correct fix for the sieve example to match a List-Id header that ENDS WITH ".dovecot.org>"? * I assume, that other users on my servers will run into similar problems once I upgrade their servers. Is it possible to detect such problematic matches in Sieve scripts? E.g. "all matches without a trailing '*' are affected", ... This would give me a chance, to inform my users or even fix their scripts in advance. Best regards, -- Patrick Cernko <pcernko(a)mpi-klsb.mpg.de> +49 681 9325 5815 Joint Scientific IT and Technical Service Max-Planck-Institute für Informatik & Softwaresysteme

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Master user login attempted without master passdbs
by horst.simon.aus＠gmail.com 21 Apr '26

21 Apr '26

Hi, I have dovecot version v2.3.21.1 and my users (username(a)domain.name) are in mysql, all can logon to imap and sending mail, but when I am trying to create and enable sieve scripts from an weblient (horde webmail) it fails with authentication errors. It tries to use master user authentication and the logs are showing following: A pr 15 10:34:51 auth: Debug: client in: AUTH 1 PLAIN service=sieve secured session=yTdN4nRPFcF/AAAB lip=127.0.0.1 rip=127.0.0.1 lport=4190 rport=49429 resp=aG9yc3QAaG9yc3RAaGJzaW1vbi5uZXQAYXVnQDYmOXVzdA== (previous base64 data may contain sensitive data) Apr 15 10:34:51 auth: Info: plain(horst(a)hbsimon.net,127.0.0.1,<yTdN4nRPFcF/AAAB>): login user: Master user login attempted without master passdbs Apr 15 10:34:51 auth: Debug: auth(horst(a)hbsimon.net,127.0.0.1,<yTdN4nRPFcF/AAAB>): Auth request finished Apr 15 10:34:51 auth: Debug: auth client connected (pid=1478) Apr 15 10:34:53 auth: Debug: client passdb out: FAIL 1 user=horst(a)hbsimon.net Apr 15 10:34:53 managesieve-login: Info: Disconnected: Connection closed (auth failed, 1 attempts in 2 secs): user=<horst(a)hbsimon.net>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, secured, session=<yTdN4nRPFcF/AAAB> Apr 15 10:35:06 auth: Debug: client in: AUTH 1 PLAIN service=sieve secured session=VEgr43RPGMF/AAAB lip=127.0.0.1 rip=127.0.0.1 lport=4190 rport=49432 resp=aG9yc3QAaG9yc3RAaGJzaW1vbi5uZXQAYXVnQDYmOXVzdA== (previous base64 data may contain sensitive data) Apr 15 10:35:06 auth: Info: plain(horst(a)hbsimon.net,127.0.0.1,<VEgr43RPGMF/AAAB>): login user: Master user login attempted without master passdbs Apr 15 10:35:06 auth: Debug: auth(horst(a)hbsimon.net,127.0.0.1,<VEgr43RPGMF/AAAB>): Auth request finished Apr 15 10:35:06 auth: Debug: auth client connected (pid=1484) Apr 15 10:35:08 auth: Debug: client passdb out: FAIL 1 user=horst(a)hbsimon.net Apr 15 10:35:08 managesieve-login: Info: Disconnected: Connection closed (auth failed, 1 attempts in 2 secs): user=<horst(a)hbsimon.net>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, secured, session=<VEgr43RPGMF/AAAB> How can I bypass the master user login and use the assigned user or what should the master user be and how to create it? Thanks and Regards, Horst

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Dovecot 2.4 SETQUOTA, how to allow (admin) users to set quota (and write it back to LDAP)
by Johannes Nohl 20 Apr '26

20 Apr '26

Is it true that Dovecot dismissed the functionality of SETQUOTA with version 2.4.0 - without any replacement? see https://dovecot.org/mailman3/archives/list/dovecot-news@dovecot.org/message… Does this also applies to 2.4.2 and 2.4.3, or does the mechanism of plugin imap_quota returned (manual reads that there are no options to this plugin)? IMAP always replies `c008 NO [NOPERM] Permission denied (0.001 + 0.000 secs).` If you can activate the former `quota_set` option, how to combine it with LDAP? I know that you can read Quota from LDAP with userdb field `quota_storage_size = {ldap:quotaBytes}B`. But how to set it? I also remember an old opinion that writing LDAP is to slow, you should store quota e.g. in a text file and write it back to LDAP time shifted. That would be fine for me - however, how to enable SETQUOTA then? Thank you for help. -- Johannes Nohl postmaster(a)i-t-cloud.de

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Config: Reading value from file for password does not work
by René Neumann 19 Apr '26

19 Apr '26

Hi, I want to read the ldap auth-dn password from a file to avoid having it as part of the configuration (which may be checked into VCS). I specified ldap_auth_dn_password = </some/file where /some/file contains the password without extra whitespace (esp. there is no `\n`, I checked with xxd). But ldap auth does not succeed because of a wrong password. Password itself does work though, as checked with ldapsearch (even using the same file as password provider) `doveconf -x -P` *does* show the correct value. The same issue has been reported back in 2019 [1], without any reply though :-/ Any ideas? Thanks, René [1] https://dovecot.org/list/dovecot/2019-September/117100.html

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[Bug Report] 2.4.3 on macOS: anvil panics at anvil-connection.c:727 on every IMAP client handshake
by I-K-D-T＠web.de 18 Apr '26

18 Apr '26

Hi Dovecot developers, I'm hitting a reproducible anvil panic on macOS when any IMAP client tries to connect. Every client handshake triggers an `i_unreached()` assertion in `anvil-connection.c:727`, causing the anvil child to be killed with SIGABRT. Dovecot keeps restarting anvil, but every subsequent connection attempt triggers the same panic, so the service effectively cannot accept logins. ## Environment - Dovecot: 2.4.3 (e278b1e09b), Pigeonhole 2.4.3 (0bf9ee48) -- from Homebrew - OS: macOS 15.6 (Sequoia, Darwin 24.6.0, arm64/Apple Silicon, APFS) - Mail client: Mozilla Thunderbird 149.0.2 - Dovecot started via `sudo brew services start dovecot` (launchd) ## Reproducing 1. Fresh macOS install of Dovecot 2.4.3 via Homebrew. 2. Configure a minimal single-user IMAP setup with `passdb static` / `userdb static`, SSL on port 993 with a self-signed cert, Maildir storage (config at end of this mail). 3. Start Dovecot as root via launchd (`sudo brew services start dovecot`). 4. Connect any IMAP client to localhost:993 (I used Thunderbird 149 with a permanent cert exception for the self-signed certificate). 5. The client hangs / reports "server closed the connection" / sees no folders. 6. `dovecot.log` fills with repeated entries like the following: ``` anvil: Warning: conn unix:anvil (uid=0): Handshake with duplicate service=imap-login pid=-1 - replacing the old connection anvil: Panic: file anvil-connection.c: line 727: unreached anvil: Error: Raw backtrace: 0 libdovecot.0.dylib backtrace_append + 72 -> 1 libdovecot.0.dylib backtrace_get + 44 -> 2 libdovecot.0.dylib default_fatal_finish + 72 -> 3 libdovecot.0.dylib default_error_handler -> 4 libdovecot.0.dylib i_internal_error_handler -> 5 libdovecot.0.dylib i_fatal -> 6 libdovecot.0.dylib default_write -> 7 anvil anvil_connection_input_line -> 8 libdovecot.0.dylib connection_input_read_stream + 196 -> 9 libdovecot.0.dylib connection_input_default + 72 -> 10 libdovecot.0.dylib io_loop_call_io + 116 -> 11 libdovecot.0.dylib io_loop_handler_run_internal + 284 -> 12 libdovecot.0.dylib io_loop_handler_run + 220 -> 13 libdovecot.0.dylib io_loop_run + 88 -> 14 libdovecot.0.dylib master_service_run + 292 -> 15 anvil main + 368 -> 16 dyld start + 6076 anvil: Fatal: master: service(anvil): child NNNN killed with signal 6 (core dumps disabled) ``` The key signature is the two-line sequence: ``` Warning: conn unix:anvil (uid=0): Handshake with duplicate service=imap-login pid=-1 - replacing the old connection Panic: file anvil-connection.c: line 727: unreached ``` Every IMAP client handshake produces this. The `pid=-1` in the handshake warning looks suspicious -- it appears anvil is either not receiving a valid pid from imap-login or is registering a second connection with the same service name before the first is cleaned up. ## Workarounds attempted (none succeeded) - User-level setup with default_login_user=andreas -> same panic - Root-level setup with default_login_user=andreas -> same panic - Root-level setup with default_login_user=_www (unprivileged macOS service account with uid=70) -> same panic - Adding `default_vsz_limit = unlimited` (required separately on macOS because setrlimit(RLIMIT_DATA) fails with EINVAL on Darwin) -> did not affect anvil - Plaintext IMAP on 143 (no TLS) vs. IMAPS on 993 with self-signed cert -> same panic in both - Restarting Dovecot via launchd (`sudo brew services stop/start dovecot`) -> the panic recurs on the next connection ## `doveconf -n` output ``` # 2.4.3 (e278b1e09b): /opt/homebrew/etc/dovecot/dovecot.conf # Pigeonhole version 2.4.3 (0bf9ee48) # OS: Darwin 24.6.0 arm64 apfs # Hostname: macbook-air-von-andreas.local dovecot_config_version = 2.4.3 auth_mechanisms = plain login default_internal_group = _www default_internal_user = _www default_login_user = _www default_vsz_limit = unlimited dovecot_storage_version = 2.4.3 info_log_path = /opt/homebrew/var/log/dovecot/dovecot-info.log listen = 127.0.0.1 log_path = /opt/homebrew/var/log/dovecot/dovecot.log mail_driver = maildir mail_gid = staff mail_home = /Users/andreas/mail/%{user} mail_path = /Users/andreas/mail/%{user} mail_uid = andreas protocols = imap ssl_server { cert_file = /opt/homebrew/etc/dovecot/ssl/dovecot.crt key_file = /opt/homebrew/etc/dovecot/ssl/dovecot.key } service imap-login { inet_listener imap { port = 143 } inet_listener imaps { port = 993 ssl = yes } } passdb static { password = # hidden } userdb static { fields { gid = staff home = /Users/andreas/mail/%{user} uid = andreas } } namespace inbox { mailbox_list_layout = fs inbox = yes prefix = separator = / } ``` ## What I would expect The anvil connection from imap-login should register with a valid pid (not -1) or anvil should tolerate the re-registration gracefully instead of hitting an i_unreached() assertion. ## Note on `dovecot-sysreport` Running `dovecot-sysreport` as the normal user fails with permission errors on `/opt/homebrew/var/run/dovecot/*` sockets (log-errors, master). The `grep -P` usage inside the script also fails on BSD grep (macOS). Let me know if a sysreport archive would be useful -- I can re-run with sudo and adjust grep if needed. Happy to provide further reproduction details, additional log output, or test any fix suggestions. Thanks for Dovecot. Andreas Marth I-K-D-T(a)web.de

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imap-sieve, question concerning "sieve_user_email" and variables, migration from 2.3 to 2.4
by Claus-Justus Heine 17 Apr '26

17 Apr '26

Hi there, I have a question concerning the configuration setting sieve_user_email In a v2.3 setup I had it set to sieve_user_email = %Ln(a)some.concrete.domain Now I am trying to migrate to v2.4 and thought the direct translation from the old variable expansion scheme to the new scheme deployed in v2.4 would be sieve_user_email = %{user|username|lower}(a)some.concrete.domain However, this does not work. Testing the documentation yields the following error: # dovecot -n -c dovecot.conf > /dev/null doveconf: Error: sieve: sieve settings: Failed to parse configuration: Failed to expand sieve_user_email setting variables: Unknown variable 'user' doveconf: Fatal: Error in configuration file dovecot.conf: Failed to initialize Sieve Setting "sieve_user_email" to something without variable expansion or just commenting it out yields a configuration which is accepted by "dovecot -n". Now I wonder: a) v2.3 did not complain. But perhaps just because it was using "%Ln" literally? b) In case it did work in v2.3, should it work in v2.4 also? And if so: what would be the correct syntax / variable names? c) Under which circumstances is this setting "sieve_user_email" used? The documentation states: https://doc.dovecot.org/main/core/summaries/settings.html#sieve_user_email > The primary e-mail address for the user. > > This is used as a default when no other appropriate address is available for sending messages. > > If this setting is not configured, either the postmaster or null <> address is used as a sender, depending on the action involved. > > This setting is important when there is no message envelope to extract addresses from, such as when the script is executed in IMAP. I thought that then it would make sense to use something which depends on the login-name of the IMAP-user? Or was this "sieve_user_email" intended to hold just one static email like "my_global_catch_all(a)some.concrete.domain"? Kind thanks for clarification, best regards Claus -- Claus-Justus Heine himself(a)claus-justus-heine.de http://www.claus-justus-heine.de/ Schatzmeister der Camerata Academica Freiburg e.V. --- www.cafev.de

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still a compile error in 2.4.3
by matthias 14 Apr '26

14 Apr '26

Hi, I got this message while I compile the version 2.4.3: libtool: error: cannot find the library '../../src/lib-lua/libdovecot-lua.la' or unhandled argument '../../src/lib-lua/libdovecot-lua.la' Thanks Matthias

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INBOX.dovecot.sieve not selectable
by 87auteur-niobium＠icloud.com 14 Apr '26

14 Apr '26

Hi folks, I’m seeing “INBOX.dovecot.sieve” listed on the response of the IMAP LIST command, but attempting to select the mailbox fails with “Internal server error occurred. Refer to the server log for more information”. I assume INBOX.dovecot.sieve is an internal/system folder that shouldn’t be on the LIST response. Is this a known issue? If it is, is it being tracked anywhere (I don’t see an “Issues” tab on GitHub for Dovecot Core)?

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imap-login not passing DSN through
by Hadmut Danisch 14 Apr '26

14 Apr '26

Hi, I have a problem with postfix + dovecot 1:2.3.21+dfsg1-2ubuntu6.3 on Ubuntu Server 24.04: When using dovecot's imap-login to verify users and passwords againgst dovecot's user list, it doesn't pass the DSN flag through, therefore effectively disabling DSN. Postfix, submission port bound to 127.0.0.1, port 587: 250-myhostname 250-PIPELINING 250-SIZE 18432000 250-ETRN 250-STARTTLS 250-ENHANCEDSTATUSCODES 250-8BITMIME 250-DSN 250-SMTPUTF8 250 CHUNKING but imap-login (configured to forward to 127.0.0.1:587): 250-myhostname 250-8BITMIME 250-AUTH PLAIN 250-BURL imap 250-CHUNKING 250-ENHANCEDSTATUSCODES 250-SIZE 250 PIPELINING So both the size limit and DSN are not passed through, SMTPUTF8 either. Even setting imap_capability = +DSN in 20-imap.conf doesn't help. What is keeping dovecot's imap-login from offering DSN? best regards Hadmut Hi, I have a problem with postfix + dovecot 1:2.3.21+dfsg1-2ubuntu6.3 on Ubuntu Server 24.04: When using dovecot's imap-login to verify users and passwords againgst dovecot's user list, it doesn't pass the DSN flag through, therefore effectively disabling DSN. Postfix, submission port bound to 127.0.0.1, port 587: 250-myhostname 250-PIPELINING 250-SIZE 18432000 250-ETRN 250-STARTTLS 250-ENHANCEDSTATUSCODES 250-8BITMIME 250-DSN 250-SMTPUTF8 250 CHUNKING but imap-login (configured to forward to 127.0.0.1:587): 250-myhostname 250-8BITMIME 250-AUTH PLAIN 250-BURL imap 250-CHUNKING 250-ENHANCEDSTATUSCODES 250-SIZE 250 PIPELINING So both the size limit and DSN are not passed through, SMTPUTF8 either. Even setting imap_capability = +DSN in 20-imap.conf doesn't help. What is keeping dovecot's imap-login from offering DSN? best regards Hadmut

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doveadm batch crash
by Jonathan Casiot 13 Apr '26

13 Apr '26

Hi I'm having an issue with doveadm batch - the following command always crashes: doveadm batch : mailbox status all inbox Whereas the following work as expected: doveadm mailbox status all inbox doveadm batch : mailbox list Any assistance gratefully received. Debug output from the crash: Debug: Loading modules from directory: /usr/lib64/dovecot Debug: Module loaded: /usr/lib64/dovecot/lib01_acl_plugin.so Debug: Module loaded: /usr/lib64/dovecot/lib10_mail_crypt_plugin.so Debug: Module loaded: /usr/lib64/dovecot/lib90_stats_plugin.so Debug: Loading modules from directory: /usr/lib64/dovecot/doveadm Debug: Module loaded: /usr/lib64/dovecot/doveadm/lib10_doveadm_acl_plugin.so Debug: Skipping module doveadm_expire_plugin, because dlopen() failed: /usr/lib64/dovecot/doveadm/lib10_doveadm_expire_plugin.so: undefined symbol: expire_set_deinit (this is usually intentional, so just ignore this message) Debug: Skipping module doveadm_quota_plugin, because dlopen() failed: /usr/lib64/dovecot/doveadm/lib10_doveadm_quota_plugin.so: undefined symbol: quota_user_module (this is usually intentional, so just ignore this message) Debug: Skipping module doveadm_fts_lucene_plugin, because dlopen() failed: /usr/lib64/dovecot/doveadm/lib20_doveadm_fts_lucene_plugin.so: undefined symbol: lucene_index_iter_deinit (this is usually intentional, so just ignore this message) Debug: Skipping module doveadm_fts_plugin, because dlopen() failed: /usr/lib64/dovecot/doveadm/lib20_doveadm_fts_plugin.so: undefined symbol: fts_user_get_language_list (this is usually intentional, so just ignore this message) Debug: Module loaded: /usr/lib64/dovecot/doveadm/libdoveadm_mail_crypt_plugin.so doveadm(jc): Debug: Effective uid=1001, gid=100, home=/home/jc doveadm(jc): Debug: acl: No acl_shared_dict setting - shared mailbox listing is disabled doveadm(jc): Debug: mail_crypt_plugin: mail_crypt_curve setting missing - generating EC keys disabled doveadm(jc): Debug: Namespace inbox: type=private, prefix=, sep=., inbox=yes, hidden=no, list=yes, subscriptions=yes location=mdbox:~/mdbox:ALT=~/Archive/tape/mdbox doveadm(jc): Debug: fs: root=/home/jc/mdbox, index=, indexpvt=, control=, inbox=, alt=/home/jc/Archive/tape/mdbox doveadm(jc): Debug: acl: initializing backend with data: vfile doveadm(jc): Debug: acl: acl username = jc doveadm(jc): Debug: acl: owner = 1 doveadm(jc): Debug: acl vfile: Global ACLs disabled doveadm(jc): Panic: file mail-storage.c: line 875 (mailbox_set_reason): assertion failed: (reason != NULL) doveadm(jc): Error: Raw backtrace: /usr/lib64/dovecot/libdovecot.so.0(+0xa0e9e) [0x7fc993023e9e] -> /usr/lib64/dovecot/libdovecot.so.0(default_fatal_handler+0x2a) [0x7fc993023f0a] -> /usr/lib64/dovecot/libdovecot.so.0(i_fatal+0) [0x7fc992fb3c97] -> /usr/lib64/dovecot/libdovecot-storage.so.0(+0x49856) [0x7fc993301856] -> /usr/bin/doveadm(+0x348e2) [0x5631dbb5f8e2] -> /usr/bin/doveadm(+0x2e1ad) [0x5631dbb591ad] -> /usr/bin/doveadm(+0x2bd2c) [0x5631dbb56d2c] -> /usr/bin/doveadm(+0x2c92a) [0x5631dbb5792a] -> /usr/bin/doveadm(doveadm_mail_try_run+0x215) [0x5631dbb58285] -> /usr/bin/doveadm(main+0x46a) [0x5631dbb473fa] -> /lib64/libc.so.6(__libc_start_main+0xf5) [0x7fc992bd83d5] -> /usr/bin/doveadm(+0x1c565) [0x5631dbb47565] Aborted (core dumped) And doveconf -n output: # 2.2.36 (1f10bfa63): /etc/dovecot/dovecot.conf # OS: Linux 3.10.0-957.1.3.el7.x86_64 x86_64 CentOS Linux release 7.6.1810 (Core) # Hostname: ### redacted ### first_valid_gid = 100 first_valid_uid = 1000 last_valid_gid = 100 last_valid_uid = 1999 listen = * login_greeting = IMAP ready login_log_format_elements = user=<%u> method=%m rip=%r lip=%l mpid=%e session=<%{session}> %k mail_attribute_dict = file:%h/mdbox/dovecot-attributes mail_location = mdbox:~/mdbox:ALT=~/Archive/tape/mdbox mail_plugins = acl stats mail_crypt mailbox_list_index = yes mdbox_rotate_size = 16 M namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = separator = . } passdb { driver = pam } plugin { acl = vfile mail_crypt_global_private_key = <### redacted ### mail_crypt_global_public_key = <### redacted ### mail_crypt_save_version = 2 stats_memory_limit = 16 M stats_refresh = 30 secs stats_track_cmds = yes } postmaster_address = ### redacted ### protocols = imap service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } } service imap-login { process_limit = 200 process_min_avail = 4 service_count = 1 } service stats { fifo_listener stats-mail { group = users mode = 01224 } } ssl = required ssl_cert = <### redacted ### ssl_key = # hidden, use -P to show it ssl_prefer_server_ciphers = yes ssl_protocols = !SSLv2 !SSLv3 !TLSv1 userdb { driver = passwd } verbose_proctitle = yes protocol imap { imap_idle_notify_interval = 10 mins imap_metadata = yes mail_max_userip_connections = 20 mail_plugins = acl stats mail_crypt imap_acl imap_stats } Regards, -- Jonathan

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