CentOS - Jul 2010 - acl and chmod interaction

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#$ setfacl -m u:mf:r bla
#$ getfacl bla
# file: bla
# owner: root
# group: root
user::rw-
user:mf:r--
group::r--
mask::r--
other::r--

It is readable by mf like intended.

#$ chmod go-rwx bla
#$ getfacl bla
# file: bla
# owner: root
# group: root
user::rw-
user:mf:r--			#effective:---
group::r--			#effective:---
mask::---
other::---

It is not readable no more by mf which was not intended.
Obviously the mask:: is cleared, but why ? OTOH group::r ?

Confused am i

- -- 
Regards,
markus
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On 20/07/2010 02:17, Markus Falb wrote:
> #$ setfacl -m u:mf:r bla
> #$ getfacl bla
...
> It is readable by mf like intended.
> 
> #$ chmod go-rwx bla
...
> It is not readable no more by mf which was not intended.
> Obviously the mask:: is cleared, but why ? OTOH group::r ?
to answer myself (from acl(5))

snip

The ACL_MASK entry denotes the maximum access
rights that can be granted by entries of type
ACL_USER, ACL_GROUP_OBJ, or ACL_GROUP.

The permissions defined for the file group correspond to the permissions
of the ACL_GROUP_OBJ entry, if the ACL has no ACL_MASK entry. If the ACL
has an ACL_MASK entry, then the permissions defined for the file group
correspond to the permissions of the ACL_MASK entry.

snap

> Confused am i
I tend to think of acls as an extended variant of the classical group
permission now.

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