From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752288AbeDXR45 (ORCPT ); Tue, 24 Apr 2018 13:56:57 -0400 Received: from shards.monkeyblade.net ([184.105.139.130]:38040 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750735AbeDXR4y (ORCPT ); Tue, 24 Apr 2018 13:56:54 -0400 Date: Tue, 24 Apr 2018 13:56:51 -0400 (EDT) Message-Id: <20180424.135651.492329246141701047.davem@davemloft.net> To: paul@paul-moore.com Cc: dh.herrmann@gmail.com, linux-kernel@vger.kernel.org, jmorris@namei.org, teg@jklm.no, sds@tycho.nsa.gov, selinux@tycho.nsa.gov, linux-security-module@vger.kernel.org, eparis@parisplace.org, serge@hallyn.com, netdev@vger.kernel.org Subject: Re: [PATCH 2/3] net/unix: hook unix_socketpair() into LSM From: David Miller In-Reply-To: References: <20180423133015.5455-1-dh.herrmann@gmail.com> <20180423133015.5455-3-dh.herrmann@gmail.com> X-Mailer: Mew version 6.7 on Emacs 25.3 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Paul Moore Date: Tue, 24 Apr 2018 13:55:31 -0400 > On Mon, Apr 23, 2018 at 9:30 AM, David Herrmann wrote: >> Use the newly created LSM-hook for unix_socketpair(). The default hook >> return-value is 0, so behavior stays the same unless LSMs start using >> this hook. >> >> Signed-off-by: David Herrmann >> --- >> net/unix/af_unix.c | 5 +++++ >> 1 file changed, 5 insertions(+) >> >> diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c >> index 68bb70a62afe..bc9705ace9b1 100644 >> --- a/net/unix/af_unix.c >> +++ b/net/unix/af_unix.c >> @@ -1371,6 +1371,11 @@ static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr, >> static int unix_socketpair(struct socket *socka, struct socket *sockb) >> { >> struct sock *ska = socka->sk, *skb = sockb->sk; >> + int err; >> + >> + err = security_unix_stream_socketpair(ska, skb); >> + if (err) >> + return err; > > I recognize that AF_UNIX is really the only protocol that supports > socketpair(2) at the moment, but I like to avoid protocol specific LSM > hooks whenever possible. Unless someone can think of a good > objection, I would prefer to see the hook placed in __sys_socketpair() > instead (and obviously drop the "unix_stream" portion from the hook > name). The counterargument is that after 30 years no other protocol has grown usage of this operation. :-)