Re: permission problems with script run via crondargs -m

On 5/12/20 12:13 PM, Lukas Vrabec wrote:
> On 5/12/20 5:50 PM, Robert Moskowitz wrote:
>>
>> On 5/12/20 11:36 AM, Lukas Vrabec wrote:
>>> On 5/12/20 1:31 PM, Robert Moskowitz wrote:
>>>> Lukas,
>>>>
>>>> Failed again last night see the end of this message.
>>>>
>>>> On 5/11/20 9:40 AM, Lukas Vrabec wrote:
>>>>> On 5/11/20 3:19 PM, Robert Moskowitz wrote:
>>>>>> On 5/11/20 9:04 AM, Lukas Vrabec wrote:
>>>>>>> On 5/11/20 2:23 PM, Robert Moskowitz wrote:
>>>>>>>> A little background first.
>>>>>>>>
>>>>>>>> This is for Fedora 32 workstation which does not come with a
>>>>>>>> default MTA
>>>>>>>> and thus there is a slight challenge (ahem) getting CRON's output
>>>>>>>> into
>>>>>>>> the local mailstore.  I don't want to install an MTA (leave why for
>>>>>>>> Fedora users list discuss) and "procmail -f cron" leaves out a DATE
>>>>>>>> header.  So I wrote my own little script that I put in
>>>>>>>> /usr/local/mycron
>>>>>>>> that takes the output from cron and appends the proper content to
>>>>>>>> /var/spool/mail/$USER.
>>>>>>>>
>>>>>>>> Works fine for my personal crontab, but has selinux problems for
>>>>>>>> logwatch running as root (and probably any other cron task
>>>>>>>> running as
>>>>>>>> root).
>>>>>>>>
>>>>>>>> So I first got told by selinux troubleshooting that I needed:
>>>>>>>>
>>>>>>>> ausearch -c 'mycron' --raw | audit2allow -M my-mycron
>>>>>>>> semodule -X 300 -i my-mycron.pp
>>>>>>>>
>>>>>>>> Which I did.  Then after this night's run of logwatch, I see that I
>>>>>>>> have
>>>>>>>> the selinux troubleshoot icon, but when I look, it is empty? So I
>>>>>>>> grep
>>>>>>>> messages for logwatch, then grep the time it was running and
>>>>>>>> found the
>>>>>>>> following:
>>>>>>>>
>>>>>>>> May 11 03:43:19 lx140e setroubleshoot[121345]: SELinux is preventing
>>>>>>>> mycron from add_name
>>>>>>>> access on the directory root. For complete SELinux messages run:
>>>>>>>> sealert
>>>>>>>> -l 8eb93a73-c7ff-
>>>>>>>> 42ec-bee1-594d77540808
>>>>>>>> May 11 03:43:19 lx140e python3[121345]: SELinux is preventing mycron
>>>>>>>> from add_name access
>>>>>>>> on the directory root.#012#012*****  Plugin catchall (100.
>>>>>>>> confidence)
>>>>>>>> suggests   ********
>>>>>>>> ******************#012#012If you believe that mycron should be
>>>>>>>> allowed
>>>>>>>> add_name access on
>>>>>>>> the root directory by default.#012Then you should report this as a
>>>>>>>> bug.#012You can generat
>>>>>>>> e a local policy module to allow this access.#012Do#012allow this
>>>>>>>> access
>>>>>>>> for now by execut
>>>>>>>> ing:#012# ausearch -c 'mycron' --raw | audit2allow -M my-mycron#012#
>>>>>>>> semodule -X 300 -i my
>>>>>>>> -mycron.pp#012
>>>>>>>> May 11 03:43:23 lx140e systemd[1]:
>>>>>>>> dbus-:[email protected]:
>>>>>>>>      Succeeded.
>>>>>>>>
>>>>>>>> So it looks like now I am told to run:
>>>>>>>>
>>>>>>>> ausearch -c 'mycron' --raw | audit2allow -M my-mycron
>>>>>>>> semodule -X 300 -i my-mycron.pp
>>>>>>>>
>>>>>>>> Wait, that is the same I ran earlier?  And why did I have to grep
>>>>>>>> messages to find these?
>>>>>>>>
>>>>>>> Hi,
>>>>>>>
>>>>>>> Could you please share output of this command:
>>>>>>>
>>>>>>> # sealert -l 8eb93a73-c7ff-42ec-bee1-594d77540808
>>>>>> # sealert -l 8eb93a73-c7ff-42ec-bee1-594d77540808
>>>>>> Error
>>>>>> query_alerts error (1003): id
>>>>>> (8eb93a73-c7ff-42ec-bee1-594d77540808) not
>>>>>> found
>>>>>>
>>>>>> And from the first selinux alert:
>>>>>>
>>>>>> # sealert -l d05d8373-fae7-447e-b45a-74940959809e
>>>>>> Error
>>>>>> query_alerts error (1003): id
>>>>>> (d05d8373-fae7-447e-b45a-74940959809e) not
>>>>>> found
>>>>>>
>>>>>> I viewed the alerts with the SELinux troubleshooter, but I did NOT
>>>>>> tell
>>>>>> it to delete the alert :(
>>>>>>
>>>>> No problem, are you able to reproduce it? If yes, please do and then
>>>>> attach:
>>>>>
>>>>> # ausearch -m AVC,USER_AVC -ts today
>>>> # ausearch -m AVC,USER_AVC -ts today
>>>> ----
>>>> time->Tue May 12 03:22:06 2020
>>>> type=AVC msg=audit(1589268126.630:3796): avc:  denied  { add_name } for
>>>> pid=142359 comm="mycron" name="root"
>>>> scontext=system_u:system_r:logwatch_t:s0-s0:c0.c1023
>>>> tcontext=system_u:object_r:mail_spool_t:s0 tclass=dir permissive=0
>>>>
>>>> May 12 03:22:06 lx140e audit[142359]: AVC avc:  denied  { add_name }
>>>> for  pid=142359 comm="mycron" name="root"
>>>> scontext=system_u:system_r:logwatch_t:s0-s0:c0.c1023
>>>> tcontext=system_u:object_r:mail_spool_t:s0 tclass=dir permissive=0
>>>> May 12 03:22:09 lx140e systemd[1]: Started
>>>> dbus-:[email protected].
>>>> May 12 03:22:09 lx140e audit[1]: SERVICE_START pid=1 uid=0
>>>> auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0
>>>> msg='unit=dbus-:1.1-org.fedoraproject.Setroubleshootd@20 comm="systemd"
>>>> exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
>>>> May 12 03:22:13 lx140e systemd[1]: Started
>>>> dbus-:[email protected].
>>>> May 12 03:22:13 lx140e audit[1]: SERVICE_START pid=1 uid=0
>>>> auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0
>>>> msg='unit=dbus-:1.1-org.fedoraproject.SetroubleshootPrivileged@10
>>>> comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=?
>>>> terminal=? res=success'
>>>> May 12 03:22:19 lx140e setroubleshoot[142374]: SELinux is preventing
>>>> mycron from add_name access on the directory root. For complete SELinux
>>>> messages run: sealert -l 9fd5890f-400b-4ae0-8a98-43575ac4913a
>>>> May 12 03:22:19 lx140e python3[142374]: SELinux is preventing mycron
>>>> from add_name access on the directory root.#012#012*****  Plugin
>>>> catchall (100. confidence) suggests **************************#012#012If
>>>> you believe that mycron should be allowed add_name access on the root
>>>> directory by default.#012Then you should report this as a bug.#012You
>>>> can generate a local policy module to allow this access.#012Do#012allow
>>>> this access for now by executing:#012# ausearch -c 'mycron' --raw |
>>>> audit2allow -M my-mycron#012# semodule -X 300 -i my-mycron.pp#012
>>>> May 12 03:22:23 lx140e systemd[1]:
>>>> dbus-:[email protected]: Succeeded.
>>>> May 12 03:22:23 lx140e audit[1]: SERVICE_STOP pid=1 uid=0
>>>> auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0
>>>> msg='unit=dbus-:1.1-org.fedoraproject.Setroubleshootd@20 comm="systemd"
>>>> exe="/usr/lib/systemd/systemd" hostname=? addr=? terminal=? res=success'
>>>> May 12 03:22:23 lx140e systemd[1]:
>>>> dbus-:[email protected]: Consumed 3.306s
>>>> CPU time.
>>>> May 12 03:22:25 lx140e systemd[1]:
>>>> dbus-:[email protected]:
>>>> Succeeded.
>>>> May 12 03:22:25 lx140e audit[1]: SERVICE_STOP pid=1 uid=0
>>>> auid=4294967295 ses=4294967295 subj=system_u:system_r:init_t:s0
>>>> msg='unit=dbus-:1.1-org.fedoraproject.SetroubleshootPrivileged@10
>>>> comm="systemd" exe="/usr/lib/systemd/systemd" hostname=? addr=?
>>>> terminal=? res=success'
>>>> May 12 03:22:25 lx140e systemd[1]:
>>>> dbus-:[email protected]:
>>>> Consumed 5.271s CPU time.
>>>>
>>>> # sealert -l 9fd5890f-400b-4ae0-8a98-43575ac4913a
>>>> Error
>>>> query_alerts error (1003): id (9fd5890f-400b-4ae0-8a98-43575ac4913a) not
>>>> found
>>>>
>>>>
>>> Can you attach your "mycron" script? THere is some issue with SELinux
>>> domain transition.
>> Oh, and this script runs fine for root's crontab tasks.  It is failing
>> on whatever kicks off logwatch.
>>
> Yes, that's the problem.
>
>
> Can you please run:
>
> # semanage fcontext -a -t sendmail_exec_t /usr/local/mycron
> # restorecon -Rv /usr/local
>
> and then reproduce it? This could help.
>

restorecon -Rv /usr/local
Relabeled /usr/local/mycron from unconfined_u:object_r:usr_t:s0 to 
unconfined_u:object_r:sendmail_exec_t:s0


Interesting...

Now we will see what happens tonight.

_______________________________________________
selinux mailing list -- [email protected]
To unsubscribe send an email to [email protected]
Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/
List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
List Archives: https://lists.fedoraproject.org/archives/list/[email protected]