help adding a type attribute to a domain

[Dominick Grift]

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On 03/11/2011 06:30 PM, Maria Iano wrote:
> 
> On Mar 11, 2011, at 11:52 AM, Daniel J Walsh wrote:
> 
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>> On 03/11/2011 11:48 AM, Dominick Grift wrote:
>>> On 03/11/2011 05:42 PM, Daniel J Walsh wrote:
>>>> On 03/11/2011 10:57 AM, Maria Iano wrote:
>>>>> I'm getting a denial that audit2why says is due to constraints.
>>>>> Sesearch does show that the action has an allow rule.
>>>
>>>>> Here are the audit messages:
>>>
>>>>> host=eng-vocngcn03.eng.gci type=AVC  
>>>>> msg=audit(1299844473.770:740848):
>>>>> avc:  denied  { sigkill } for  pid=22927 comm="kill"
>>>>> scontext=system_u:system_r:rgmanager_t:s0
>>>>> tcontext=system_u:system_r:unconfined_t:s0-s0:c0.c1023  
>>>>> tclass=process
>>>
>>>>> host=eng-vocngcn03.eng.gci type=SYSCALL
>>>>> msg=audit(1299844473.770:740848): arch=c000003e syscall=62  
>>>>> success=yes
>>>>> exit=0 a0=19ba a1=9 a2=9 a3=0 items=0 ppid=20173 pid=22927
>>>>> auid=4294967295 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0
>>>>> fsgid=0 tty=(none) ses=4294967295 comm="kill" exe="/bin/kill"
>>>>> subj=system_u:system_r:rgmanager_t:s0 key=(null)
>>>
>>>> You have rgmanager sending a kill signal to a process running as
>>>> unconfined_t
>>>
>>> There is no proof that its rgmanager doing that imho. Since  
>>> rgmanager_t
>>> is an unconfined_domain it could be any generic application started  
>>> by a
>>> process running in the rgmanager_t domain (eventually started by  
>>> rgmanager)
>>>
>>>> I would bet this process is running with the wrong domain.  I don't
>>>> think you want rgmanager_t sending kill signals to user processes.
>>>
>>>> What process was it trying to kill?
>>>>> Here is the result of running sesearch on that same server:
>>>
>>>>> [root at eng-vocngcn03]# sesearch --allow -s rgmanager_t -t  
>>>>> unconfined_t -
>>>>> c process -p sigkill
>>>>> Found 1 av rules:
>>>>>    allow rgmanager_t unconfined_t : process { sigchld sigkill };
>>>
>>>>> Here is what audit2why says:
>>>
>>>>> [root at eng-vocngcn03]# echo 'host=eng-vocngcn03.eng.gci type=AVC
>>>>> msg=audit(1299844473.770:740848): avc:  denied  { sigkill } for
>>>>> pid=22927 comm="kill" scontext=system_u:system_r:rgmanager_t:s0
>>>>> tcontext=system_u:system_r:unconfined_t:s0-s0:c0.c1023  
>>>>> tclass=process'
>>>>> | audit2why
>>>>> host=eng-vocngcn03.eng.gci type=AVC  
>>>>> msg=audit(1299844473.770:740848):
>>>>> avc:  denied  { sigkill } for  pid=22927 comm="kill"
>>>>> scontext=system_u:system_r:rgmanager_t:s0
>>>>> tcontext=system_u:system_r:unconfined_t:s0-s0:c0.c1023  
>>>>> tclass=process
>>>>>         Was caused by:
>>>>>                 Constraint violation.
>>>>>                 Check policy/constraints.
>>>>>                 Typically, you just need to add a type attribute to
>>>>> the domain to satisfy the constraint.
>>>
>>>>> This is a RHEL 5.5 server and it doesn't have the policy source  
>>>>> and I
>>>>> don't see an rpm available with that. I can't find a constraints  
>>>>> file,
>>>>> and I assume that's because it doesn't have the source. I'm  
>>>>> trying to
>>>>> work out how to add the necessary type attribute to the domain. I  
>>>>> do
>>>>> have a custom policy on the system. It's very long so I'll  
>>>>> include the
>>>>> relevant pieces:
>>>
>>>>> require {
>>>>>         type rgmanager_t;
>>>>>         type unconfined_t;
>>>>>         class process { sigkill signal };
>>>>> ..<snip>...
>>>>> }
>>>
>>>>> allow rgmanager_t unconfined_t:process sigkill;
>>>>> ..<snip>...
>>>
>>>>> Is there something I can add to my policy to resolve the  
>>>>> constraints
>>>>> issue?
>>>
>>>>> Thanks,
>>>>> Maria
>>>>> --
>>>>> selinux mailing list
>>>>> selinux at lists.fedoraproject.org
>>>>> https://admin.fedoraproject.org/mailman/listinfo/selinux
>>>
>>>
>>>
>>
>> Right although unconifned_t:s0-s0:c0.c1023 is almost assured a  
>> logged in
>> user.  It could have been a shell secript started via a remove ssh  
>> call
>>
>> If an init script had started an unconfined_exec_t executable it would
>> probably run as s0.
>>
>> To solve the constraint you would need to add
>>
>> `mcs_killall(rgmanager_t)
>>
> 
> Where do I add that line? I tried adding it to my te file but got an  
> error.
> 
> [root at eng-vocdeviodb01 ~]# /usr/bin/checkmodule -M -m -o /root/ 
> ngiodb.mod /root/ngiodb.te
> /usr/bin/checkmodule:  loading policy configuration from /root/ngiodb.te
> (unknown source)::ERROR 'syntax error' at token 'mcs_killall' on line  
> 111:
> allow rgmanager_t unconfined_t:process sigkill;
> mcs_killall(rgmanager_t);
> /usr/bin/checkmodule:  error(s) encountered while parsing configuration
> 

mcs_killall(rgmanager_t) (without the `)

But try my solution first because this solution does not deal with the
other sigchld issue.

> --
> selinux mailing list
> selinux at lists.fedoraproject.org
> https://admin.fedoraproject.org/mailman/listinfo/selinux

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