On Apr 18 12:48, Achim Gratz wrote:
> Corinna Vinschen writes:
> > Right.  It's a compromise.  I take it you don't like the extra behaviour
> > for SYSTEM/Admins.  Neither do I.  Others are desperately waiting for
> > more.  The problem with compromises is, they are usually best if nobody
> > is completely satisfied ;)
> 
> I have argued against treating them differently, purely based on
> consistency between the Windows and POSIX world (where possible at all).
> Other considerations have prevailed (maybe rightly so), so I'm not too
> surprised to find some inconsistency in the results.

Neither am I.  We're walking a fine line between two very different
systems handling ACLs.

> I don't think you'll find a UN*X system that reports executable
> permission on a plain file simply because root accesses it (for a
> directory it would do that of course).  The situation in the above case
> is on the face of it different (the ACL actually has the executable bit
> set), but as I understand you've been wanting to treat both secondaries
> like the root account.  I think it would be more sensible to ignore that
> execute permission on plain files when otherwise none is granted (since
> chmod will never mask it).  That would eliminate another reason to
> entirely remove the default/inherited ACL and I don't think it has any
> consequences on the Windows side.

Hang on.  As far as access(2) is concerned, Cygwin can't ignore the
execute permssions since the OS has its say here.  I don't think it's
overly helpful to tweak the result after the OS returned it, dependent
on the user being SYSTEM or having the Admins group in the token.
That's a lot of extra work for a questionable gain.

What we *could* try to do is to tweak the actual SYSTEM and Admins ACE,
though.  Rather than ignoring the CLASS_OBJ/ACL_MASK value completely
for them, we could apply the execute bit part only.  Usually it doesn't
make sense for SYSTEM/Admins having execute perms if nobody else has
since it's with high probability no executable file.

Would that make sense?


Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Maintainer                 cygwin AT cygwin DOT com
Red Hat