From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:34604 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753906AbbLKUVt (ORCPT ); Fri, 11 Dec 2015 15:21:49 -0500 Subject: Patch "packet: infer protocol from ethernet header if unset" has been added to the 4.1-stable tree To: daniel@iogearbox.net, davem@davemloft.net, edumazet@google.com, gregkh@linuxfoundation.org, willemb@google.com Cc: , From: Date: Fri, 11 Dec 2015 08:48:52 -0800 Message-ID: <14498525323548@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled packet: infer protocol from ethernet header if unset to the 4.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: packet-infer-protocol-from-ethernet-header-if-unset.patch and it can be found in the queue-4.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Fri Dec 11 11:39:13 EST 2015 From: Daniel Borkmann Date: Wed, 11 Nov 2015 23:25:43 +0100 Subject: packet: infer protocol from ethernet header if unset From: Daniel Borkmann [ Upstream commit c72219b75fde768efccf7666342282fab7f9e4e7 ] In case no struct sockaddr_ll has been passed to packet socket's sendmsg() when doing a TX_RING flush run, then skb->protocol is set to po->num instead, which is the protocol passed via socket(2)/bind(2). Applications only xmitting can go the path of allocating the socket as socket(PF_PACKET, , 0) and do a bind(2) on the TX_RING with sll_protocol of 0. That way, register_prot_hook() is neither called on creation nor on bind time, which saves cycles when there's no interest in capturing anyway. That leaves us however with po->num 0 instead and therefore the TX_RING flush run sets skb->protocol to 0 as well. Eric reported that this leads to problems when using tools like trafgen over bonding device. I.e. the bonding's hash function could invoke the kernel's flow dissector, which depends on skb->protocol being properly set. In the current situation, all the traffic is then directed to a single slave. Fix it up by inferring skb->protocol from the Ethernet header when not set and we have ARPHRD_ETHER device type. This is only done in case of SOCK_RAW and where we have a dev->hard_header_len length. In case of ARPHRD_ETHER devices, this is guaranteed to cover ETH_HLEN, and therefore being accessed on the skb after the skb_store_bits(). Reported-by: Eric Dumazet Signed-off-by: Daniel Borkmann Acked-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/packet/af_packet.c | 11 +++++++++++ 1 file changed, 11 insertions(+) --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -2121,6 +2121,15 @@ static bool ll_header_truncated(const st return false; } +static void tpacket_set_protocol(const struct net_device *dev, + struct sk_buff *skb) +{ + if (dev->type == ARPHRD_ETHER) { + skb_reset_mac_header(skb); + skb->protocol = eth_hdr(skb)->h_proto; + } +} + static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb, void *frame, struct net_device *dev, int size_max, __be16 proto, unsigned char *addr, int hlen) @@ -2202,6 +2211,8 @@ static int tpacket_fill_skb(struct packe dev->hard_header_len); if (unlikely(err)) return err; + if (!skb->protocol) + tpacket_set_protocol(dev, skb); data += dev->hard_header_len; to_write -= dev->hard_header_len; Patches currently in stable-queue which might be from daniel@iogearbox.net are queue-4.1/packet-infer-protocol-from-ethernet-header-if-unset.patch queue-4.1/bpf-array-fix-heap-out-of-bounds-access-when-updating-elements.patch queue-4.1/ipv6-sctp-implement-sctp_v6_destroy_sock.patch queue-4.1/packet-only-allow-extra-vlan-len-on-ethernet-devices.patch queue-4.1/net-scm-fix-pax-detected-msg_controllen-overflow-in-scm_detach_fds.patch queue-4.1/packet-fix-tpacket_snd-max-frame-len.patch queue-4.1/packet-always-probe-for-transport-header.patch queue-4.1/packet-do-skb_probe_transport_header-when-we-actually-have-data.patch queue-4.1/tools-net-use-include-uapi-with-__exported_headers__.patch