From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Herbert Subject: [PATCH net-next 1/2] kcm: Only allow TCP sockets to be attached to a KCM mux Date: Tue, 23 Jan 2018 17:00:13 -0800 Message-ID: <20180124010014.2070-2-tom@quantonium.net> References: <20180124010014.2070-1-tom@quantonium.net> Cc: netdev@vger.kernel.org, rohit@quantonium.net, jchapman@katalix.com, Tom Herbert To: davem@davemloft.net Return-path: Received: from mail-pf0-f194.google.com ([209.85.192.194]:43130 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932083AbeAXBAk (ORCPT ); Tue, 23 Jan 2018 20:00:40 -0500 Received: by mail-pf0-f194.google.com with SMTP id y26so1713099pfi.10 for ; Tue, 23 Jan 2018 17:00:40 -0800 (PST) In-Reply-To: <20180124010014.2070-1-tom@quantonium.net> Sender: netdev-owner@vger.kernel.org List-ID: TCP sockets for IPv4 and IPv6 that are not listeners or in closed stated are allowed to be attached to a KCM mux. Fixes: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module") Reported-by: syzbot+8865eaff7f9acd593945@syzkaller.appspotmail.com Signed-off-by: Tom Herbert --- net/kcm/kcmsock.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c index d4e98f20fc2a..474ea2200592 100644 --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -1391,6 +1391,15 @@ static int kcm_attach(struct socket *sock, struct socket *csock, if (csk->sk_family == PF_KCM) return -EOPNOTSUPP; + /* Only allow TCP sockets to be attached for now */ + if ((csk->sk_family != AF_INET && csk->sk_family != AF_INET6) || + csk->sk_protocol != IPPROTO_TCP) + return -EOPNOTSUPP; + + /* Don't allow listeners or closed sockets */ + if (csk->sk_state == TCP_LISTEN || csk->sk_state == TCP_CLOSE) + return -EOPNOTSUPP; + psock = kmem_cache_zalloc(kcm_psockp, GFP_KERNEL); if (!psock) return -ENOMEM; -- 2.11.0