dovecot - Sep 2003 - Odd problem with dovecot segfaulting

Hi All,

I installed dovecot on one of my servers the other day, and I want to use
it in a vhosting environment. To this end, I have set it up to use
password file authentication with a passwd file specified by me. This file
will contain both system users and virtual accounts.

To test it, I set up two accounts in the dovecot passwd file. One is a
system user, I give his home dir in the correct field, along with the
MD5 hash of his password in its field, and everything seems to work OK (he
can login, read mail out of /var/spool/mail/user etc.).

The seconmd account is a vhosted account, and I set the uid and gid to
that under which the vhosting account exists. I did not set a home dir,
but I set a mail dir in /var/spool/vmail/imap/vhost/user, and made this
dir group writeable by dovecot. The user can login, but immediately upon
authentication, dovecot segfaults (the log reports an "Internal login
failure" and the authentication process is killed with signal 11, i.e. a
segfault).

Has anyone encountered this before? Is this even the right way to set up
vhosting (I don't want to go with LDAP or SQL authentication right at the
moment, but I may move to that later on)? Are there any things I should
look for (this is probably due to something I've done wrong) or make
dovecot be a bit more verbose in reporting errors to its log?

Thanks in advance for any help. From what I've seen so far, dovecot looks
like an excellent product.

Best,
Tim Miller

On Sat, 2003-09-27 at 09:01, Tim Miller wrote:
> The seconmd account is a vhosted account, and I set the uid and gid to
> that under which the vhosting account exists. I did not set a home dir,
> but I set a mail dir in /var/spool/vmail/imap/vhost/user, and made this
> dir group writeable by dovecot. The user can login, but immediately upon
> authentication, dovecot segfaults (the log reports an "Internal login
> failure" and the authentication process is killed with signal 11, i.e.
a
> segfault).
This patch fixes it: http://dovecot.fi/auth-home.patch
> Has anyone encountered this before? Is this even the right way to set up
> vhosting (I don't want to go with LDAP or SQL authentication right at
the
> moment, but I may move to that later on)? 
You could also just set the home directory to the mail dir. It doesn't
really matter which way you use.

The reason why I used SQL authentication rather than passwd-file is that
Postfix doesn't really like passwd-file type files. And it's a bit
easier to write some simple web user interface for changing the data.
> Are there any things I should
> look for (this is probably due to something I've done wrong) or make
> dovecot be a bit more verbose in reporting errors to its log?
There's auth_verbose setting but that's mostly useful for figuring out
why authentication fails. Dovecot should have verbose enough logging for
all error handling, but for crashes it can't say much more than that it
crashed.