When performing an imap search, I hit the following assertion failure: imap(vmail): Panic: file unichar.c: line 128 (uni_ucs4_to_utf8_c): assertion failed: (chr <= 0x40000000) imap(vmail): Error: Raw backtrace: /usr/lib/dovecot/imap [0x80c7f7f] -> /usr/lib/dovecot/imap [0x80c7d6a] -> /usr/lib/dovecot/imap [0x80d8616] -> /usr/lib/dovecot/imap(uni_utf8_to_decomposed_titlecase+0x9f) [0x80d892f] -> /usr/lib/dovecot/imap(message_decoder_decode_next_block+0x679) [0x80c46e9] -> /usr/lib/dovecot/imap(message_search_more+0x3e) [0x80c2e8e] -> /usr/lib/dovecot/imap(message_search_msg+0x72) [0x80c3012] -> /usr/lib/dovecot/imap [0x8093f47] -> /usr/lib/dovecot/imap [0x80b7719] -> /usr/lib/dovecot/imap(mail_search_args_foreach+0x32) [0x80b77c2] -> /usr/lib/dovecot/imap(index_storage_search_next_nonblock+0x243) [0x8093af3] -> /usr/lib/dovecot/imap [0x805cdc7] -> /usr/lib/dovecot/imap [0x805d138] -> /usr/lib/dovecot/imap(io_loop_handle_timeouts+0x112) [0x80ce892] -> /usr/lib/dovecot/imap(io_loop_handler_run+0x66) [0x80cf316] -> /usr/lib/dovecot/imap(io_loop_run+0x28) [0x80ce768] -> /usr/lib/dovecot/imap(main+0x4ab) [0x806675b] -> /lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xc8) [0xb7e68ea8] -> /usr/lib/dovecot/imap [0x8059141]

My quick analysis: This seemed to be caused by a single message in this mailbox. I think dovecot is expanding base64 encoded binary data and then inevitably failing on the utf8 conversion of the decoded random binary data.

The mime headers for this message are: MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="------------080305000603070709090808" ... This is a multi-part message in MIME format. --------------080305000603070709090808 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit <text content> ... --------------080305000603070709090808 Content-Type: application/x-zip-compressed; name="xxxxxxxx.zip" Content-Transfer-Encoding: base64 Content-Disposition: inline; filename="xxxxxxxxxxxx.zip"

<base64 encoded zip file> ... --------------080305000603070709090808--

# dovecot -n # 1.1.beta6: /etc/dovecot/dovecot.conf protocols: imap pop3 listen: 127.0.0.1 disable_plaintext_auth: no login_dir: /var/run/dovecot/login login_executable(default): /usr/lib/dovecot/imap-login login_executable(imap): /usr/lib/dovecot/imap-login login_executable(pop3): /usr/lib/dovecot/pop3-login login_greeting_capability(default): yes login_greeting_capability(imap): yes login_greeting_capability(pop3): no first_valid_uid: 89 mail_location: maildir:~/Maildir mail_debug: yes mmap_disable: yes mail_nfs_storage: yes mail_nfs_index: yes mail_executable(default): /usr/lib/dovecot/rawlog /usr/lib/dovecot/imap mail_executable(imap): /usr/lib/dovecot/rawlog /usr/lib/dovecot/imap mail_executable(pop3): /usr/lib/dovecot/rawlog /usr/lib/dovecot/pop3 mail_plugins(default): fts fts_lucene mail_plugins(imap): fts fts_lucene mail_plugins(pop3): quota mail_plugin_dir(default): /usr/lib/dovecot/modules/imap mail_plugin_dir(imap): /usr/lib/dovecot/modules/imap mail_plugin_dir(pop3): /usr/lib/dovecot/modules/pop3 mail_log_prefix: %Us(%u[%r]): mail_log_max_lines_per_sec: 100 pop3_uidl_format(default): %08Xu%08Xv pop3_uidl_format(imap): %08Xu%08Xv pop3_uidl_format(pop3): %f auth default: mechanisms: plain cram-md5 verbose: yes debug: yes debug_passwords: yes passdb: driver: sql args: /etc/dovecot/dovecot-sql.conf userdb: driver: sql args: /etc/dovecot/dovecot-sql.conf socket: type: listen client: path: /var/spool/postfix/private/auth mode: 432 user: postfix group: postfix master: path: /var/run/dovecot/auth-master mode: 384 user: vmail group: vmail plugin: fts: lucene