Description of problem:

The postfix MTA stops working if stopped then started with

postfix start

then stopped with 

postfix stop

then try to start with

service postfix start


---

The startup will not work because for some reason the

postfix start

command creates a master.pid file under

/var/spool/postfix/pid

as

-rw-------. root root unconfined_u:object_r:var_run_t:s0 master.pid

while the

service postfix start

creates it as:

-rw-------. root root unconfined_u:object_r:postfix_var_run_t:s0 master.pid


This condition is giving messages like:

type=AVC msg=audit(1463156977.010:11428): avc:  denied  { signal } for  pid=19396 comm="postfix-script" scontext=unconfined_u:system_r:postfix_master_t:s0 tcontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tclass=process
type=AVC msg=audit(1463157084.605:11435): avc:  denied  { read write } for  pid=19876 comm="cleanup" name="unix.cleanup" dev=xvda1 ino=270120 scontext=unconfined_u:system_r:postfix_cleanup_t:s0 tcontext=unconfined_u:object_r:var_run_t:s0 tclass=file
type=AVC msg=audit(1463157106.254:11436): avc:  denied  { read write } for  pid=19882 comm="showq" name="unix.showq" dev=xvda1 ino=270263 scontext=unconfined_u:system_r:postfix_showq_t:s0 tcontext=unconfined_u:object_r:var_run_t:s0 tclass=file

The problem is with the owner and context of the /var/spool/postfix/pid directory and the files in there.


May 13 17:45:25 elk-a postfix/postfix-script[20376]: starting the Postfix mail system
May 13 17:45:25 elk-a postfix/master[20377]: daemon started -- version 2.6.6, configuration /etc/postfix
May 13 17:45:25 elk-a postfix/cleanup[20381]: fatal: open lock file pid/unix.cleanup: cannot open file: Permission denied
May 13 17:45:26 elk-a postfix/master[20377]: warning: process /usr/libexec/postfix/cleanup pid 20381 exit status 1
May 13 17:45:26 elk-a postfix/master[20377]: warning: /usr/libexec/postfix/cleanup: bad command startup -- throttling
May 13 17:45:26 elk-a postfix/showq[20383]: fatal: open lock file pid/unix.showq: cannot open file: Permission denied
May 13 17:45:27 elk-a postfix/master[20377]: warning: process /usr/libexec/postfix/showq pid 20383 exit status 1
May 13 17:45:27 elk-a postfix/master[20377]: warning: /usr/libexec/postfix/showq: bad command startup -- throttling


ALSO:

restorecon reset /var/spool/postfix/pid context unconfined_u:object_r:postfix_spool_t:s0->unconfined_u:object_r:var_run_t:s0

Looks like by default the pid directory has var_run_t assigned but that disagrees with the policy as evidenced by the restorecon.




Version-Release number of selected component (if applicable):

postfix-2.6.6-6.el6_7.1.x86_64

selinux-policy-targeted-3.7.19-279.el6_7.9.noarch
selinux-policy-3.7.19-279.el6_7.9.noarch

selinux-policy-3.7.19-292.el6.noarch
selinux-policy-targeted-3.7.19-292.el6.noarch

^ this update did not solve it.


How reproducible:

Every time you kill it, even with updated selinux-policy.

Steps to Reproduce:
1. service postfix stop
2. ls -Z /var/spool/postfix/pid/
3. postfix start
4. ls -Z /var/spool/postfix/pid/
5. postfix stop
6. ls -Z /var/spool/postfix/pid/
7. service postfix start

FIX:

8. chcon -t postfix_var_run_t /var/spool/postfix/pid/master.pid
9. ls -Z /var/spool/postfix/pid/
10. service postfix start


Actual results:

Postfix won't start

Expected results:

Postfix starts.

Additional info:

The built-in policy also disagrees on the right context for

/var/spool/postfix/pid/

To reproduce:

1. service postfix stop
2. ls -Zd /var/spool/postfix/pid/ (it is var_run_t)
3. rm -rf /var/spool/postfix/pid/
4. service postfix start
5. ls -Zd /var/spool/postfix/pid/ (it is postfix_spool_t)
6. mailq