Follow up.
This is the bt of the running (stale in R state) dovecot-auth . It seems that it get frozen AFTER many crashes.
Anyway the stack got corrupted. I hope it's useful.
(gdb) bt #0 0x004b6559 in malloc_consolidate () from /lib/tls/libc.so.6 #1 0x004b5aea in _int_malloc () from /lib/tls/libc.so.6 #2 0x004b4e9d in malloc () from /lib/tls/libc.so.6 #3 0x004ab38d in open_memstream () from /lib/tls/libc.so.6 #4 0x0051c3f2 in vsyslog () from /lib/tls/libc.so.6 #5 0x08057ba4 in syslog_handler () #6 0x08057cc0 in i_syslog_info_handler () #7 0x08057ab9 in i_info () #8 0x08050160 in login_connection_create () #9 0x0805aa98 in io_loop_handler_run () #10 0x00000010 in ?? () #11 0x000003e5 in ?? () #12 0x0057b238 in __DTOR_END__ () from /lib/tls/libc.so.6 #13 0xbfeb49d4 in ?? () ---Type <return> to continue, or q <return> to quit--- #14 0x00000001 in ?? () #15 0xbfeb4918 in ?? () #16 0x0805cf11 in o_stream_send () Previous frame inner to this frame (corrupt stack?) (gdb)
Bye.