Re: Missing permissions

[Aki Tuomi]

On 11/04/2020 15:47 Alex JOST < jost+li...@dimejo.at> wrote:

Am 11.04.2020 um 13:00 schrieb Andrei Petru Mura:

Hi,

After configuring systemd unit with ReadWritePaths=/home/mail, I get the

following error logs in audit:

type=AVC msg=audit(1586604621.637:6736): avc: denied { write } for

pid=12750 comm="imap" name="Maildir" dev="dm-3" ino=438370738

scontext=system_u:system_r:dovecot_t:s0

tcontext=unconfined_u:object_r:etc_runtime_t:s0 tclass=dir permissive=0

type=SYSCALL msg=audit(1586604621.637:6736): arch=c000003e syscall=83

success=no exit=-13 a0=55b493a7f338 a1=1ed a2=ffffffff a3=fffffffffffffcd8

items=0 ppid=12735 pid=12750 auid=4294967295 uid=1005 gid=1005 euid=1005

suid=1005 fsuid=1005 egid=1005 sgid=1005 fsgid=1005 tty=(none)

ses=4294967295 comm="imap" exe="/usr/libexec/dovecot/imap"

subj=system_u:system_r:dovecot_t:s0 key=(null)

type=PROCTITLE msg=audit(1586604621.637:6736): proctitle="dovecot/imap"

type=AVC msg=audit(1586604621.638:6737): avc: denied { write } for

pid=12750 comm="imap" name="Maildir" dev="dm-3" ino=438370738

scontext=system_u:system_r:dovecot_t:s0

tcontext=unconfined_u:object_r:etc_runtime_t:s0 tclass=dir permissive=0

type=SYSCALL msg=audit(1586604621.638:6737): arch=c000003e syscall=21

success=no exit=-13 a0=55b493a7f508 a1=2 a2=55b493a7f388 a3=fffffffe

items=0 ppid=12735 pid=12750 auid=4294967295 uid=1005 gid=1005 euid=1005

suid=1005 fsuid=1005 egid=1005 sgid=1005 fsgid=1005 tty=(none)

ses=4294967295 comm="imap" exe="/usr/libexec/dovecot/imap"

subj=system_u:system_r:dovecot_t:s0 key=(null)

type=PROCTITLE msg=audit(1586604621.638:6737): proctitle="dovecot/imap"

I have SELinux enabled, on CentOS.

If I run:

audit2why < /var/log/audit/audit.log

I get:

type=AVC msg=audit(1586601301.044:6707): avc: denied { write } for

pid=9930 comm="imap" name="Maildir" dev="dm-3" ino=438370738

scontext=system_u:system_r:dovecot_t:s0

tcontext=unconfined_u:object_r:etc_runtime_t:s0 tclass=dir permissive=0

Was caused by:

Missing type enforcement (TE) allow rule.

I think it's important to know that I'm trying to use dovecot with virtual

users. If I try to configure it with PAM authentication using system users,

it works well.

Any suggestions on this?

Looks like /home/mail as mail store isn't included in the default

SELinux policy. Did you make sure that the correct SELinux type is set

on the directories?

https://www.unix.com/man-page/centos/8/dovecot_selinux/

If this isn't enough to get you going you might need to create your own

policy. The following steps should be all that it takes to create your

own policy.

Check that grep includes only lines that you want included in your new

policy:

grep dovecot /var/log/audit/audit.log | audit2allow -w

Create your new policy for Dovecot and install it:

grep dovecot /var/log/audit/audit.log | audit2allow -M dovecot_custom

semodule -i dovecot_custom.pp

--

Alex JOST

Or just label the directory with mail_home_rw_t

---
Aki Tuomi