dovecot - Apr 2017 - [BUG] config-parser.c: line 89 - crash on comma in namespace mailbox

Hi!
On the latest versions (2.2.28, 2.2.29.x) we get crash on dovecot config parse.
Error in config parser when checking namespace mailbox name. 
Reason: comma in mailbox name.
Worked well in versions < 2.2.22. Do not know if it was working on
2.2.23-2.2.27, skipped this versions.

Example:
namespace inbox {
  mailbox "&BB4EQgQ,BEAEMAQyBDsENQQ9BD0ESwQ1-" {
    special_use = \Sent
  }
}

Error:
# dovecot -n
# 2.2.29.1 (e0b76e3): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.4.18 (29cc74d)
doveconf: Panic: file config-parser.c: line 89 (config_add_type): assertion
failed: (ret > 0)
doveconf: Error: Raw backtrace: /usr/lib64/dovecot/libdovecot.so.0(+0x9b89a)
[0x7fa1f8cc789a] ->
/usr/lib64/dovecot/libdovecot.so.0(default_fatal_handler+0x32) [0x7fa1f8cc81d2]
-> /usr/lib64/dovecot/libdovecot.so.0(+0x2f81a) [0x7fa1f8c5b81a] ->
/usr/bin/doveconf() [0x40b213] ->
/usr/bin/doveconf(config_parser_apply_line+0x763) [0x40b983] ->
/usr/bin/doveconf(config_parse_file+0x821) [0x40c351] ->
/usr/bin/doveconf(main+0x255) [0x406845] ->
/lib64/libc.so.6(__libc_start_main+0xfd) [0x7fa1f88b6d1d] ->
/usr/bin/doveconf() [0x4051f9]
doveconf: Error: managesieve-login: dump-capability process killed with signal 6
doveconf: Panic: file config-parser.c: line 89 (config_add_type): assertion
failed: (ret > 0)
doveconf: Error: Raw backtrace: /usr/lib64/dovecot/libdovecot.so.0(+0x9b89a)
[0x7f6dfa20489a] ->
/usr/lib64/dovecot/libdovecot.so.0(default_fatal_handler+0x32) [0x7f6dfa2051d2]
-> /usr/lib64/dovecot/libdovecot.so.0(+0x2f81a) [0x7f6dfa19881a] ->
/usr/bin/doveconf() [0x40b213] ->
/usr/bin/doveconf(config_parser_apply_line+0x763) [0x40b983] ->
/usr/bin/doveconf(config_parse_file+0x821) [0x40c351] ->
/usr/bin/doveconf(main+0x255) [0x406845] ->
/lib64/libc.so.6(__libc_start_main+0xfd) [0x7f6df9df3d1d] ->
/usr/bin/doveconf() [0x4051f9]


Info:
&BB4EQgQ,BEAEMAQyBDsENQQ9BD0ESwQ1- - is a valid mailbox name for russian
Outlook folder "????????????".

On 17 Apr 2017, at 15.45, Alek <finalek at ya.ru>
wrote:
> 
> Hi!
> On the latest versions (2.2.28, 2.2.29.x) we get crash on dovecot config
parse.
> Error in config parser when checking namespace mailbox name. 
> Reason: comma in mailbox name.
> Worked well in versions < 2.2.22. Do not know if it was working on
2.2.23-2.2.27, skipped this versions.
> 
> Example:
> namespace inbox {
>  mailbox "&BB4EQgQ,BEAEMAQyBDsENQQ9BD0ESwQ1-" {
>    special_use = \Sent
>  }
> }
> 
> doveconf: Panic: file config-parser.c: line 89 (config_add_type): assertion
failed: (ret > 0)
Crash isn't good, but you're not supposed to be using mUTF-7 names in
here (or anywhere in Dovecot configs). Did it ever really even work?
> Info:
> &BB4EQgQ,BEAEMAQyBDsENQQ9BD0ESwQ1- - is a valid mailbox name for
russian Outlook folder "????????????".
You should be using this name as UTF-8 directly.