chmod issue on 3.1.7.

[Brian Inglis]

On 2020-10-10 13:41, Ken Brown via Cygwin wrote:
> On 10/10/2020 12:32 PM, Kaz Kylheku (Cygwin) via Cygwin wrote:
>> Hi all,
>>
>> Running this Cygwin on a Windows 10 system:
>>
>>    0:DESKTOP-K8055OB:~$ uname -a
>>    CYGWIN_NT-10.0-WOW DESKTOP-K8055OB 3.1.7(0.340/5/3) 2020-08-22 19:03 i686
>> Cygwi
>>
>> When a file is created, and permissions set as follows:
>>
>>    0:DESKTOP-K8055OB:~$ touch tempfile
>>    0:DESKTOP-K8055OB:~$ chmod 03777 tempfile
>>    0:DESKTOP-K8055OB:~$ ls -l tempfile
>>    -rwsrwsrwt 1 kaz kaz 0 Oct 10 08:59 tempfile
>>
>> Then "chmod u=" is not able to clear the owner's permissions to nothing:
>>
>>    0:DESKTOP-K8055OB:~$ chmod u= tempfile
>>    0:DESKTOP-K8055OB:~$ ls -l tempfile
>>    -rwxrwsrwt 1 kaz kaz 0 Oct 10 08:59 tempfile
>>
>> As you can see, it has no effect. The expected value is ----rwsrwt.
>>
>> I tried both with 64 and 32 bit Cygwin: same deal.
>>
>> This is not a problem with the chmod utility.  I ran into this as a failing
>> test case against a chmod library function in a programming language.
>>
>> http://www.kylheku.com/cgit/txr/tree/tests/018/chmod.tl
>>
>> The test cases pass until the "u=", which fails in the same way.
>> This does not use the chmod utility.
>>
>> It's an issue with the chmod system call.
>>
>> This used to work on my older Cygwin installation, which was around 2.5.
> 
> FWIW, I can't reproduce this on my system:
> 
> $ uname -a
> CYGWIN_NT-10.0-WOW XXX 3.1.7(0.340/5/3) 2020-08-22 19:03 i686 Cygwin
> 
> $ touch tempfile
> 
> $ ls -l tempfile
> -rw-r--r-- 1 kbrown None 0 2020-10-10 15:16 tempfile
> 
> $ chmod 03777 tempfile
> 
> $ ls -l tempfile
> -rwxrwsrwt 1 kbrown None 0 2020-10-10 15:16 tempfile
> 
> $ chmod u= tempfile
> 
> $ ls -l tempfile
> ----rwsrwt 1 kbrown None 0 2020-10-10 15:16 tempfile

D/ACLs on the directory could restore/maintain the permissions:
could we please see the output from ls -l, getfacl, and icacls on the directory
and file?

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

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