[Dovecot] v2.2 getting NULL pointer reference with shared namespace in mailbox_tree?

[Walter Steiner]

> You most likely want to have subscriptions=no for your shared namespace. Also you most likely want to enable ACL plugin.

Yes - thank you for your comment!  The ACLs I had configured before are
not enabled in this minimalistic configuration because of crashes when
running doveadm backup -R ... imapc: with ACLs enabled.

You wrote that you are continuing debugging "my problem".  Regardless
of this, should I investigate / file this ACL (related) bug?

With todays nightly:

dsync(wsunpriv at iai.uni-bonn.de): Debug: acl: initializing backend with data: vfile:/m/d/etc/acl:cache_secs=300
dsync(wsunpriv at iai.uni-bonn.de): Debug: acl: acl username = wsunpriv at iai.uni-bonn.de
dsync(wsunpriv at iai.uni-bonn.de): Debug: acl: owner = 0
dsync(wsunpriv at iai.uni-bonn.de): Debug: acl vfile: Global ACL directory: /m/d/etc/acl
dsync(wsunpriv at iai.uni-bonn.de): Debug: brain M: in state=recv_handshake
dsync(wsunpriv at iai.uni-bonn.de): Debug: brain M: out state=send_mailbox_tree_deletes changed=1
dsync(wsunpriv at iai.uni-bonn.de): Panic: file imapc-list.c: line 199 (imapc_list_get_vname): assertion failed: (strncmp(prefix, storage_name, prefix_len) == 0 && storage_name[prefix_len] == list->sep)
dsync(wsunpriv at iai.uni-bonn.de): Error: Raw backtrace: /m/sw/dc/2.2-20130322/lib/dovecot/libdovecot.so.0.0.0'default_fatal_finish+0x26 [0xffff80ffb60c4d34] -> /m/sw/dc/2.2-20130322/lib/dovecot/libdovecot.so.0.0.0'default_error_handler+0x0 [0xffff80ffb60c4dc3] -> /m/sw/dc/2.2-20130322/lib/dovecot/libdovecot.so.0.0.0'i_fatal+0x0 [0xffff80ffb60c50a4] -> /m/sw/dc/2.2-20130322/lib/dovecot/libdovecot-storage.so.0.0.0'imapc_list_get_vname+0xdb [0xffff80ffb5f4c4ce] -> /m/sw/dc/2.2-20130322/lib/dovecot/libdovecot-storage.so.0.0.0'mailbox_list_get_vname+0x28 [0xffff80ffb5f75ebb] -> /m/sw/dc/2.2-20130322/lib/dovecot/lib01_acl_plugin.so'acl_backend_vfile_object_init+0x92 [0xffff80ffb5e3d0fa] -> /m/sw/dc/2.2-20130322/lib/dovecot/lib01_acl_plugin.so'acl_object_init_from_name+0x2b [0xffff80ffb5e3ad88] -> /m/sw/dc/2.2-20130322/lib/dovecot/lib01_acl_plugin.so'acl_backend_get_default_rights+0x30 [0xffff80ffb5e3c9b4] -> /m/sw/dc/2.2-20130322/lib/dovecot/lib01_acl_plugin.so'acl_mailbox_try_list_fast+0xb2 [0xffff80ffb5e44b77] -> /m/sw/dc/2.2-20130322/lib/dovecot/lib01_acl_plugin.so'acl_mailbox_list_iter_init+0x188 [0xffff80ffb5e44efa] -> /m/sw/dc/2.2-20130322/lib/dovecot/libdovecot-storage.so.0.0.0'mailbox_list_iter_init_multiple+0x91 [0xffff80ffb5f8aa20] -> /m/sw/dc/2.2-20130322/lib/dovecot/libdovecot-storage.so.0.0.0'mailbox_list_iter_init+0x39 [0xffff80ffb5f8a596] -> /m/sw/dc/2.2-20130322/bin/doveadm'dsync_mailbox_tree_fill+0x103 [0x456acf] -> /m/sw/dc/2.2-20130322/bin/doveadm'dsync_brain_mailbox_trees_init+0x114 [0x449f74] -> /m/sw/dc/2.2-20130322/bin/doveadm'dsync_brain_slave_recv_handshake+0x18d [0x447703] -> /m/sw/dc/2.2-20130322/bin/doveadm'dsync_brain_run_real+0xe7 [0x447a4c] -> /m/sw/dc/2.2-20130322/bin/doveadm'dsync_brain_run+0x61 [0x447bf6] -> /m/sw/dc/2.2-20130322/bin/doveadm'cmd_dsync_run_local+0x325 [0x444b1e] -> /m/sw/dc/2.2-20130322/bin/doveadm'cmd_dsync_run+0x272 [0x445156] -> /m/sw/dc/2.2-20130322/bin/doveadm'doveadm_mail_next_user+0x189 [0x4294ba] -> /m/sw/dc/2.2-20130322/bin/doveadm'doveadm_mail_single_user+0x157 [0x429680] -> /m/sw/dc/2.2-20130322/bin/doveadm'doveadm_mail_cmd+0x3bc [0x429f24] -> /m/sw/dc/2.2-20130322/bin/doveadm'doveadm_mail_try_run+0xac [0x42a19b] -> /m/sw/dc/2.2-20130322/bin/doveadm'main+0x286 [0x4342b7] -> /m/sw/dc/2.2-20130322/bin/doveadm'_start+0x6c [0x428a8c]
Abort (core dumped)