Hello

Dovecot's IMAP process appears to be crashing at random times for a few users, but one is crashing at least 3 to 5 times an hour.

I applied these patches per http://dovecot.org/list/dovecot/2016-January/102933.html

/https://github.com/dovecot/core/commit/1ddf959a750f3860feff4ab3f0e908f327409... //https://github.com/dovecot/core/commit/c8e9fa2ffa2566e75f0500808b1bc9bf5d9db... //https://github.com/dovecot/core/commit/15307c2c91854e766bd9fb095d611a29b3f75... //https://github.com/dovecot/core/commit/c7801f830c7d2e7d340065cdd5a5c795b1726... //https://github.com/dovecot/core/commit/f136b0050b3125b466af73984177250b7ed1a... /

But it's still crashing.

# 2.2.21 (5345f22): /etc/dovecot/dovecot.conf # OS: Linux 2.6.32-604.30.3.lve1.3.63.el6.x86_64 x86_64 CloudLinux Server release 6.7 (Aleksei Gubarev) auth_cache_size = 1 k auth_mechanisms = plain login auth_username_chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!#$-=?^_{}~./@+%" disable_plaintext_auth = no first_valid_uid = 201 mail_plugins = " zlib" maildir_very_dirty_syncs = yes namespace { inbox = yes location = mailbox Archive { auto = create special_use = \Archive } mailbox Archives { auto = no special_use = \Archive } mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Junk { auto = create special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox "Sent Messages" { auto = no special_use = \Sent } mailbox Trash { auto = subscribe special_use = \Trash } prefix = INBOX. type = private } passdb { args = /usr/local/cpanel/bin/dovecot-wrap driver = checkpassword } plugin { acl = vfile quota = maildir quota_rule = INBOX.Trash:ignore } protocols = imap pop3 service auth { unix_listener auth-client { mode = 0666 } } service imap-login { client_limit = 500 inet_listener imap { address = * } inet_listener imaps { address = * } process_limit = 50 process_min_avail = 2 service_count = 0 vsz_limit = 64 M } service imap { process_limit = 512 vsz_limit = 256 M } service managesieve-login { client_limit = 500 process_limit = 50 process_min_avail = 2 service_count = 0 vsz_limit = 64 M } service managesieve { process_limit = 512 vsz_limit = 256 M } service pop3-login { client_limit = 500 inet_listener pop3 { address = * } inet_listener pop3s { address = * } process_limit = 50 process_min_avail = 2 service_count = 0 vsz_limit = 64 M } service pop3 { process_limit = 512 vsz_limit = 256 M } ssl_cert =

1 18:23:54 gw-ud3 dovecot: imap(xxxx@xxxx.com): Panic: file imap-client.c: line 849 (client_check_command_hangs): assertion failed: (!have_wait_unfinished || unfinished_count > 0) Feb 11 18:23:54 gw-ud3 dovecot: imap(xxxx@xxxx.com): Error: Raw backtrace: /usr/lib64/dovecot/libdovecot.so.0(+0x8096a) [0x7f996c47e96a] -> /usr/lib64/dovecot/libdovecot.so.0(+0x809d6) [0x7f996c47e9d6]$ Feb 11 18:23:55 gw-ud3 dovecot: imap(xxxx@xxxx.com): Fatal: master: service(imap): child 329519 killed with signal 6 (core dumped)

Here's the backtrace:

(gdb) bt full #0 0x00007f046eb2e625 in raise (sig=<value optimized out>) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64 resultvar = 0 pid = 98454 selftid = 98454 #1 0x00007f046eb2fe05 in abort () at abort.c:92 save_stage = 2 act = {__sigaction_handler = {sa_handler = 0x2, sa_sigaction = 0x2}, sa_mask = {__val = {139657018134932, 1, 18488448, 0, 139657017886537, 139657017552035, 139657017530872, 206158430224, 140725557583888, 140725557583680, 4362456, 140725557583788, 18440536, 0, 0, 6717455502603727992}}, sa_flags = 1635021663, sa_restorer = 0x7ffd38dee060} sigs = {__val = {32, 0 }} #2 0x00007f046ef10a60 in default_fatal_finish (type=<value optimized out>, status=0) at failures.c:201 backtrace = 0x1196158 "/usr/lib64/dovecot/libdovecot.so.0(+0x80a6a) [0x7f046ef10a6a] -> /usr/lib64/dovecot/libdovecot.so.0(+0x80ad6) [0x7f046ef10ad6] -> /usr/lib64/dovecot/libdovecot.so.0(i_error+0) [0x7f046eeb994f] -> dove"... #3 0x00007f046ef10ad6 in i_internal_fatal_handler (ctx=0x7ffd38dee080, format=<value optimized out>, args=<value optimized out>) at failures.c:670 status = 0 #4 0x00007f046eeb994f in i_panic (format=0x18096