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| author | Eric Dumazet <eric.dumazet@gmail.com> | 2009-10-27 02:40:35 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-10-27 09:02:33 +0100 |
| commit | 05423b241311c9380b7280179295bac7794281b6 (patch) | |
| tree | 8a84aca48cbc30b142bdf143dbf11fdbab9cad67 /net/packet | |
| parent | can: sja1000: fix bug using library functions for skb allocation (diff) | |
| download | linux-05423b241311c9380b7280179295bac7794281b6.tar.xz linux-05423b241311c9380b7280179295bac7794281b6.zip | |
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 <gertjan_hofman@yahoo.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/packet')
| -rw-r--r-- | net/packet/af_packet.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index ff752c606413..33e68f20ec61 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -79,6 +79,7 @@ #include <linux/module.h> #include <linux/init.h> #include <linux/mutex.h> +#include <linux/if_vlan.h> #ifdef CONFIG_INET #include <net/inet_common.h> @@ -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); } |