From 05423b241311c9380b7280179295bac7794281b6 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 26 Oct 2009 18:40:35 -0700 Subject: vlan: allow null VLAN ID to be used We currently use a 16 bit field (vlan_tci) to store VLAN ID/PRIO on a skb. Null value is used as a special value, meaning vlan tagging not enabled. This forbids use of null vlan ID. As pointed by David, some drivers use the 3 high order bits (PRIO) As VLAN ID is 12 bits, we can use the remaining bit (CFI) as a flag, and allow null VLAN ID. In case future code really wants to use VLAN_CFI_MASK, we'll have to use a bit outside of vlan_tci. #define VLAN_PRIO_MASK 0xe000 /* Priority Code Point */ #define VLAN_PRIO_SHIFT 13 #define VLAN_CFI_MASK 0x1000 /* Canonical Format Indicator */ #define VLAN_TAG_PRESENT VLAN_CFI_MASK #define VLAN_VID_MASK 0x0fff /* VLAN Identifier */ Reported-by: Gertjan Hofman Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/packet/af_packet.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'net/packet') diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index ff752c60641..33e68f20ec6 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -79,6 +79,7 @@ #include #include #include +#include #ifdef CONFIG_INET #include @@ -766,7 +767,7 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, getnstimeofday(&ts); h.h2->tp_sec = ts.tv_sec; h.h2->tp_nsec = ts.tv_nsec; - h.h2->tp_vlan_tci = skb->vlan_tci; + h.h2->tp_vlan_tci = vlan_tx_tag_get(skb); hdrlen = sizeof(*h.h2); break; default: @@ -1493,7 +1494,7 @@ static int packet_recvmsg(struct kiocb *iocb, struct socket *sock, aux.tp_snaplen = skb->len; aux.tp_mac = 0; aux.tp_net = skb_network_offset(skb); - aux.tp_vlan_tci = skb->vlan_tci; + aux.tp_vlan_tci = vlan_tx_tag_get(skb); put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux); } -- cgit v1.2.3