Fwd: Objects in ACL cygwin win 10

[Brian Inglis]

On 2020-10-24 01:09, Jim McNamara via Cygwin wrote:
> On Sat, Oct 24, 2020, 3:02 AM Jim McNamara wrote:
>> On Sat, Oct 24, 2020, 12:46 AM Brian Inglis wrote:
>>> On 2020-10-23 21:49, Jim McNamara via Cygwin wrote:
>>>> On Fri, Oct 23, 2020, 10:06 PM Eliot Moss wrote:

>>>>> I have to admit I am not 100% sure what you are asking, but I am 
>>>>> careful to grant SYSTEM access so that my backup program can access
>>>>> and save a copy of virtually everything

>>>> Thanks for you and Brian helping me.
>>>> I used icacls cygwin /q /c /t reset

>>> You have to be very careful using icacls and other Windows commands with
>>> Cygwin
>>> ACLs as
>>>
>>> "ICACLS preserves the canonical ordering of ACE entries:
>>>         Explicit denials
>>>         Explicit grants
>>>         Inherited denials
>>>         Inherited grants"
>>>
>>> and Cygwin's POSIX ACLs may or may not obey this canonical order; Windows
>>> File
>>> Explorer often does not consider Cygwin ACLs in what it considers
>>> canonical
>>> order and requires them to be reordered, which breaks the Cygwin
>>> permissions.
>>>
>>> Ah, that "NT AUTHORITY/SYSTEM" SID, normally paired with
>>> BUILTIN/Administrators,
>>> as users, groups, or both:
>>>
>>> $ ls -dl /proc/cygdrive/c/Users/; echo; getfacl /proc/cygdrive/c/Users/;
>>> echo;
>>> icacls C:/Users/
>>> drwxr-xr-x+ 1 SYSTEM SYSTEM 0 Apr 13  2020 /proc/cygdrive/c/Users/
>>>
>>> # file: /proc/cygdrive/c/Users/
>>> # owner: SYSTEM
>>> # group: SYSTEM
>>> user::rwx
>>> group::r-x
>>> group:Administrators:rwx        #effective:r-x
>>> group:Users:r-x
>>> mask::r-x
>>> other::r-x
>>> default:user::rwx
>>> default:group::---
>>> default:group:Administrators:rwx        #effective:r-x
>>> default:group:Users:r-x
>>> default:mask::r-x
>>> default:other::r-x
>>>
>>> C:/Users/ NT AUTHORITY\SYSTEM:(OI)(CI)(F)
>>>           BUILTIN\Administrators:(OI)(CI)(F)
>>>           BUILTIN\Users:(RX)
>>>           BUILTIN\Users:(OI)(CI)(IO)(GR,GE)
>>>           Everyone:(RX)
>>>           Everyone:(OI)(CI)(IO)(GR,GE)
>>>
>>> Successfully processed 1 files; Failed processing 0 files

>> Yes, I see now what you are saying. Didn't know why it behaves like that.
>> Do you reccomend:
>>
>> A. Noacl option  in fstab
>> B. Reinstall and leave icacls in windows alone so I can deploy in future
>> with runtime

> I decided to go with b. since windows ntfs wont recognize a and I want to
> deploy. I'm using cygwin to make agar gui apps for cobol (at least that is
> the plan).

That's normally the best way, although it may also be okay to add ACEs with
permission grants to groups as normal, or equivalents via GPOs.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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