SMBFS mount's file cannot be made executable

[Corinna Vinschen]

On Nov 12 04:29, Takashi Yano via Cygwin wrote:
> On Mon, 11 Nov 2024 14:35:55 +0100
> Corinna Vinschen wrote:
> > On Nov 11 21:19, Takashi Yano via Cygwin wrote:
> > > On Mon, 11 Nov 2024 13:03:18 +0100
> > > Corinna Vinschen wrote:
> > > > On Nov 11 20:40, Takashi Yano via Cygwin wrote:
> > > > > On Mon, 11 Nov 2024 20:32:02 +0900
> > > > > Takashi Yano via Cygwin <cygwin@cygwin.com> wrote:
> > > > > > Even with this patch, the file:
> > > > > > 
> > > > > > yano $ touch samba_test_file.txt
> > > > > > yano $ ls -l samba_test_files.txt
> > > > > > -rw-r--r-- 1 yano yano 0 Nov 11 20:25 samba_test_file.txt
> > > > > 
> > > > > Oops! This was wrong.
> > > > > -rw-r--r-- 1 Unknown+User Unix_Group+1000 0 Nov 11 20:25 samba_test_file.txt
> > > > 
> > > > That's Samba for you.  I applied your patch and created a file
> > > > on my share, and the Authenticated Users group was not in the
> > > > resulting ACL.  Only user, group, and Everyone.
> > > > 
> > > > Either way, I don't think this is the right thing to do.  Even if
> > > > the group isn't added to the ACL on my machine, it still loks like
> > > > a security problem in waiting.
> > > 
> > > Isn't this DACL here used only for access_check() (NtAccessCheck())?
> > > In my environment, the Authenticated Users does not appear in the ACL
> > > too.
> > 
> > Oh, yeah, right, *blush*.
> > 
> > But it's still not the right thing to do.  You convert the Samba ACL
> > to a Windows ACL which gives Authenticated Users full permissions.
> > So the check_access() function will return false positives, because
> > every authenticated user is in the Authenticated Users group and has
> > supposedly FILE_ALL_ACCESS.  Even if the actual function (read, write,
> > execute) will fail, the access() function will claim that every
> > authenticated user has RWX perms.
> 
> Ah, right. I have just confirmed that behaviour...
> 
> > AFAICS, the underlying problem is somehow the user mapping.  Did you
> > try with username map = /foo/bar?
> 
> Yes. However, my user name is 'yano' both in server (Linux) and
> client (Windows 10) side. So, I think there is no effect of
> 'username map'.

I have something like corinna = MY_DOMAIN\corinna in there.


Corinna