Problem with domain transition on a nfs_t mount

[David-Alexandre Davidson]

On fedora 7, lastest selinux strict policy.

I have written a selinux module which go through a domain transition 
when executing a file on a nfs mount (labeled nfs_t)
However the transition never occurs. and I get a  : denied  
execute_no_trans  on nfs_t files .

In order to find the source of the problem I have taken a file with the 
exact same context outside of the nfs mount and the transition work fine.

Here is the related part of my module:

domain_auto_trans(custom_trans_t,nfs_t,i_custom_t);
allow custom_trans_t nfs_t:file rx_file_perms;
allow custom_trans_t nfs_t:dir r_dir_perms;


Here are the details on the nfs share:

    file executed:
    -rwxrwxr-x  vu20003 vg20003 system_u:object_r:nfs_t          
/home/usera/var/bin/testphp.app

    result:
    type=AVC msg=audit(1186108700.494:230294): avc:  denied  { 
execute_no_trans } for  pid=5969 comm="custom-app" name="testphp.app" 
dev=0:18 ino=269058250 scontext=system_u:system_r:custom_trans_t:s0 
tcontext=system_u:object_r:nfs_t:s0 tclass=file


Running the same program and executing an identical file outside the nfs 
share:  (I labelled manually to match)

    file executed:
    -rwxrwxr-x  vu20003 vg20003 system_u:object_r:nfs_t          
/testphp.app

    result:
    transition is made to context  i_custom_t  , nothing is audited
    

Any idea what can cause this difference ?  I don't believe this behavior 
is normal. By the way, if I allow the execute_no_trans on nfs_t, the 
file gets executed just fine but without the expected transition...

Any help would be much appreciated !

--------------------------------------
David-Alexandre Davidson
IHQ Inc.