"Inherit Permissions" request for comments

[David Collier-Brown]

Kyle Herbert wrote:
> My premise is simple:  to inherit group permissions for a new file or
> sub-directory from the parent directory without also inheriting the group
> ownership of the new file or sub-directory from the parent directory is an
> exploitable flaw in security.  (i.e.  Inheriting the write attribute for the
> group-owner looses its meaning when the group-owner is altered.)
> 
> The current implementation of the "inherit permissions" feature in Samba
> 2.0.7 is 'flawed' (or 'featured' depending upon your point of view ;-) in
> this way.  I devised the attached patch to correct this in hopes that in
> some form it would be included in the next Samba release.

	This seems sane, and hopefully will reduce the effective
	complexity of the various create mask options...

> I'd like to hear other people's opinions.  Rather than patching Samba,
> closing this security hole can be achieved by requiring the sysadmin to use
> setgid on the share directory at the operating system level.  This
> requirement, however, can only be enforced via documentation,

	We've simulated Unix features before (indeed, with the
	create masks), so this is a credible direction.

	In addition, I'll propose that merely mapping an existing
	Unix feature to Samba is inherently a better idea than
	inventing a new one.

--dave
--
David Collier-Brown,  | Always do right. This will gratify some people
185 Ellerslie Ave.,   | and astonish the rest.        -- Mark Twain
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