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Re: Permission denied on a windows share
Randall R Schulz wrote:
Have you read the Cygwin documents regarding file modes / permissions
and how they relate to Windows permissions?
Yes I did.
If the mapping from Windows permissions to POSIX-style file modes says
the file is inaccessible, Cygwin must deny the program access even if
Windows would allow it. You've asked Cygwin to do that be enabling "ntsec."
If this is true, then I don't understand Corinna's talk about "The
mapping leak". If in then end, cygwin does its own checking, why bother
with Windows security if the mapping is flawed anyway? If the answer is
"because it works well most of the time", then this gives a false sense
of security. If some administrator tries to open a file under a specific
username for testing (like "guest") and gets a permission denied, he
will think "good, my security works, this user can't access the file".
Now the user logs in with his notepad and "oooh, wonderful, I can edit
the sshd conf or inetd.conf". Ok, this is a little farfetch because
which administrator would write config file owned by Guest on a domains
account? But the idea is there.
So the question is: if I can edit a file with Windows application,
what's the point in having more restrictions with cygwin? If cygwin was
running in a "sand-box" (I think it's the term :p), then ok. But since
cygwin application are normal Windows application with added features,
nothing keeps a cygwin trojan to run a notepad and edit the file it
couldn't edit otherwise.
The bottom line is that a POSIX-style file mode is inherently and
ineluctably an imperfect reflection of the essential Windows permissions.
As long as the discrepancy make sense to me, I'm fine. And despite all
your effort, it still doesn't. The good news is that Corinna also thinks
there is a bug. So I'm glad to be a little stubborn (if not tickheaded)
on that matter :)
You must live with the discrepancy.
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