help adding a type attribute to a domain

[Maria Iano]

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
>>
>
> 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)
>

That worked - thank you so much!

Maria