Re: [PATCH BUGFIX -rc4] Smack: Respect 'unlabeled' netlabel mode

From: Casey Schaufler
Date: Fri May 30 2008 - 19:10:54 EST



--- "Ahmed S. Darwish" <darwish.07@xxxxxxxxx> wrote:

> Hi all,
>
> In case of Smack 'unlabeled' netlabel option, Smack passes a _zero_
> initialized 'secattr' to label a packet/sock. This causes an
> [unfound domain label error]/-ENOENT by netlbl_sock_setattr().
> Above Netlabel failure leads to Smack socket hooks failure causing
> an always-on socket() -EPERM error.
>
> Such packets should have a netlabel domain agreed with netlabel to
> represent unlabeled packets. Fortunately Smack net ambient label
> packets are agreed with netlabel to be treated as unlabeled packets.
>
> Treat all packets coming out from a 'unlabeled' Smack system as
> coming from the smack net ambient label.

To date the behavior of a Smack system running with nltype
unlabeled has been carefully undefined. The way you're defining
it will result in a system in which only processes running with
the ambient label will be able to use sockets, unless I'm reading
the code incorrectly. This seems like "correct" behavior, but
I don't think it is what those who've tried it would expect.


Casey Schaufler
casey@xxxxxxxxxxxxxxxx
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/