dovecot-lda can't create /var/mail dotlocks on debian

[John Clements]

clements at desmond:/var/log$ ls -lda /var/mail
drwxrwsr-x 2 root mail 4096 Nov  2 22:07 /var/mail


Best,

John Clements

On Tue, Nov 3, 2015 at 11:52 AM, Larry Rosenman <larryrtx at gmail.com> wrote:

> what is the full permissions of /var/mail?
>
>
> ls -lda /var/mail
>
> On Tue, Nov 3, 2015 at 1:49 PM, John Clements <johnbclements at gmail.com>
> wrote:
>
>> I've been using dovecot+postfix happily for many years, and I'm now
>> configuring it for a new machine. However, I'm running into an old problem
>> again, and thinking that there must be a better solution.
>>
>> The problem is that dovecot-lda is unable to create dotlock files in the
>> /var/mail directory.
>>
>> Dovecot version: 1:2.2.13-12~deb8u1 (I'm guessing this is upstream version
>> 2.2.13)
>> OS: Debian Jessie
>>
>> Currently, my mail directory has these permissions:
>>
>> clements at desmond:~$ ls -ld /var/mail
>> drwxrwsr-x 2 root mail 4096 Nov  2 22:07 /var/mail
>> clements at desmond:~$ ls -l /var/mail
>> total 8
>> -rw------- 1 clements   mail 1382 Nov  2 21:59 clements
>> -rw------- 1 granitemon mail  530 Nov  2 22:07 granitemon
>>
>> I've added
>> mail_privileged_group = mail
>> to allow creation of the dotlock files.
>>
>> When I configure postfix to deliver using dovecot-lda, I get logs that
>> look
>> like this:
>>
>> Nov  3 11:12:20 desmond dovecot: lda(granitemon): Error:
>> setegid(privileged) failed: Operation not permitted
>> Nov  3 11:12:20 desmond dovecot: lda(granitemon): msgid=<
>> 20151103181306.A4B5B5FF32 at desmond.XXXDOMAIN.org>: save failed to INBOX:
>> BUG: Unknown internal error
>>
>> In order to isolate the error, I took postfix out of the equation, and
>> called dovecot-lda directly:
>>
>> clements at desmond:/tmp$ cat bogusmail
>> From: clements at XXXDOMAIN.org
>> To: granitemon at localhost
>> Date: November 3 2015
>> Subject: graaaah
>>
>> this is the body
>> clements at desmond:/tmp$ /usr/lib/dovecot/dovecot-lda -e -d clements <
>> bogusmail
>> BUG: Unknown internal error
>> clements at desmond:/tmp$
>>
>> In response to this, mail.log now contains this similar error:
>>
>> Nov  3 11:34:57 desmond dovecot: lda(clements): msgid=unspecified: save
>> failed to INBOX: BUG: Unknown internal error
>> Nov  3 11:34:57 desmond dovecot: lda(clements): Error: setegid(privileged)
>> failed: Operation not permitted
>>
>>
>> I've tried a number of "random internet search" solutions, including
>> - changing perms on mail files from 660 to 600
>> - enabling 'mail_access_groups=mail' in 10-mail.conf
>> - adding individual users to the mail group.
>>
>> I guess I'm pretty confident that if dovecot is writing "BUG: Unknown
>> internal error" in the logs, that this is is actually a bug in dovecot.
>>
>> OBresearch: I read through the release notes of 2.2.14 -- 2.2.19 to see if
>> a relevant-looking bug had been fixed, but nothing jumped out at me.
>> OBresearch: searching the dovecot mailing list, I found one *extremely*
>> relevant thread called "Re: [Dovecot] started with dovecot sieve
>> <http://dovecot.markmail.org/message/kgd34wberxuvmrsa?q=setegid>", but
>> there didn't seem to be a solution contained in the thread.
>>
>> Final note: this doesn't appear to be confined to debian jessie: I took a
>> look at my existing installation, and I see that in fact I just went ahead
>> and made /var/mail world-writeable, which seems... sub-optimal. I'm sure I
>> could do that here, too, but I'd certainly rather not.
>>
>> Thanks in advance, and let me know if I've left out relevant crucial
>> information.
>>
>> Best,
>>
>> John Clements
>>
>
>
>
> --
> Larry Rosenman                     http://www.lerctr.org/~ler
> Phone: +1 214-642-9640 (c)     E-Mail: larryrtx at gmail.com
> US Mail: 7011 W Parmer Ln, Apt 1115, Austin, TX 78729-6961
>