lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Thu, 24 Feb 2011 07:19:46 -0500
From:	Theodore Tso <tytso@....EDU>
To:	Jan Kara <jack@...e.cz>
Cc:	Eric Sandeen <sandeen@...hat.com>,
	ext4 development <linux-ext4@...r.kernel.org>
Subject: Re: [PATCH] ext4: enable acls and user_xattr by default


On Feb 24, 2011, at 6:49 AM, Jan Kara wrote:

>  I agree it may cause surprises although it's not true that ACL's remove
> rights. Rather on contrary ACL's can only give additional rights (i.e. you
> have 600 file + user foo can also read it) thus noacl->acl transition might
> be insecure if you have some old unwanted ACL's pending.

My understanding of how POSIX acls work is that the if you want to give
read access to user "foo" (where "foo" is not the user) is you first have to 
open up the file permissions to do the equivalent of "o+r".

See: http://acl.bestbits.at/man/man5/acl.txt

And then note how ACL_MASK corresponds to the permissions bits...

-- Ted

--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Powered by blists - more mailing lists