From 18bed89107a400af0d672ec85a270f1545db2569 Mon Sep 17 00:00:00 2001 From: Yoshiki Komachi Date: Mon, 18 Mar 2019 14:39:52 +0900 Subject: af_packet: fix the tx skb protocol in raw sockets with ETH_P_ALL I am using "protocol ip" filters in TC to manipulate TC flower classifiers, which are only available with "protocol ip". However, I faced an issue that packets sent via raw sockets with ETH_P_ALL did not match the ip filters even if they did satisfy the condition (e.g., DHCP offer from dhcpd). I have determined that the behavior was caused by an unexpected value stored in skb->protocol, namely, ETH_P_ALL instead of ETH_P_IP, when packets were sent via raw sockets with ETH_P_ALL set. IMHO, storing ETH_P_ALL in skb->protocol is not appropriate for packets sent via raw sockets because ETH_P_ALL is not a real ether type used on wire, but a virtual one. This patch fixes the tx protocol selection in cases of transmission via raw sockets created with ETH_P_ALL so that it asks the driver to extract protocol from the Ethernet header. Fixes: 75c65772c3 ("net/packet: Ask driver for protocol if not provided by user") Signed-off-by: Yoshiki Komachi Acked-by: Willem de Bruijn Signed-off-by: David S. Miller --- net/packet/af_packet.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/packet') diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 8754d7c93b84..323655a25674 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1852,7 +1852,8 @@ oom: static void packet_parse_headers(struct sk_buff *skb, struct socket *sock) { - if (!skb->protocol && sock->type == SOCK_RAW) { + if ((!skb->protocol || skb->protocol == htons(ETH_P_ALL)) && + sock->type == SOCK_RAW) { skb_reset_mac_header(skb); skb->protocol = dev_parse_header_protocol(skb); } -- cgit v1.2.3-59-g8ed1b