Hello,

I use mbox compressed by gzip as read-only folder (using zlib plugin).

This setup worked for a while, but doesn't work with latest dovecot version (2.2.27).

I have error in logs: Panic: file istream-zlib.c: line 416 (i_stream_zlib_seek): assertion failed: (ret == -1)

I can see list of messages in MUA but can't ready body of any message. I've tried to delete indexes, but it doesn't help.

Backtrace looks like: (gdb) bt #0 0x0000000011266a4a in thr_kill () from /lib/libc.so.7 #1 0x0000000011266a1b in raise () from /lib/libc.so.7 #2 0x0000000011266989 in abort () from /lib/libc.so.7 #3 0x0000000010ef3850 in default_fatal_finish (type=LOG_TYPE_PANIC, status=0) at failures.c:201 #4 0x0000000010ef5167 in i_internal_fatal_handler (ctx=0x7fffffffe010, format=0x1222cf93 "file %s: line %d (%s): assertion failed: (%s)", args=0x7fffffffdff0) at failures.c:670 #5 0x0000000010ef3e5f in i_panic (format=0x1222cf93 "file %s: line %d (%s): assertion failed: (%s)") at failures.c:275 #6 0x0000000012229238 in i_stream_zlib_seek (stream=0x118dd300, v_offset=56248, mark=false) at istream-zlib.c:416 #7 0x0000000010f05e48 in i_stream_skip (stream=0x118dd370, count=32489) at istream.c:278 #8 0x0000000010f057ba in i_stream_seek (stream=0x118dd370, v_offset=56248) at istream.c:300 #9 0x0000000010b17702 in istream_raw_mbox_get_body_size (stream=0x118ec870, expected_body_size=36695, body_size_r=0x7fffffffe2a0) at istream-raw-mbox.c:612 #10 0x0000000010b2b0aa in mbox_sync_read_next_mail (sync_ctx=0x7fffffffe418, mail_ctx=0x7fffffffe270) at mbox-sync.c:162 #11 0x0000000010b2964a in mbox_sync_loop (sync_ctx=0x7fffffffe418, mail_ctx=0x7fffffffe270, partial=false) at mbox-sync.c:1057 #12 0x0000000010b290cb in mbox_sync_do (sync_ctx=0x7fffffffe418, flags=MBOX_SYNC_UNDIRTY) at mbox-sync.c:1642 #13 0x0000000010b28999 in mbox_sync_int (mbox=0x118ee040, flags=MBOX_SYNC_UNDIRTY, lock_id=0x7fffffffe640) at mbox-sync.c:1969 #14 0x0000000010b280ea in mbox_sync (mbox=0x118ee040, flags=MBOX_SYNC_UNDIRTY) at mbox-sync.c:2022 #15 0x0000000010b28c9e in mbox_storage_sync_init (box=0x118ee040, flags=65) at mbox-sync.c:2071 #16 0x0000000010acc280 in mailbox_sync_init (box=0x118ee040, flags=65) at mail-storage.c:1740 #17 0x0000000010acb45d in mailbox_sync (box=0x118ee040, flags=65) at mail-storage.c:1788 #18 0x0000000000418cf5 in select_open (ctx=0x1184a1a8, mailbox=0x11816f50 "old/Example/INBOX.gz", readonly=false) at cmd-select.c:303 #19 0x0000000000418937 in cmd_select_full (cmd=0x1184a040, readonly=false) at cmd-select.c:426 #20 0x00000000004190f7 in cmd_select (cmd=0x1184a040) at cmd-select.c:435 #21 0x0000000000423b00 in command_exec (cmd=0x1184a040) at imap-commands.c:181 #22 0x00000000004220c0 in client_command_input (cmd=0x1184a040) at imap-client.c:986

-- Best Regards, Anton Yuzhaninov