mirrors/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2025-11-04 02:30:34 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

network: Allow af_packet to transmit +4 bytes for VLAN packets.

Browse source 
This allows user-space to send a '1500' MTU VLAN packet on a
1500 MTU ethernet frame.  The extra 4 bytes of a VLAN header is
not usually charged against the MTU when other parts of the
network stack is transmitting vlans...

Signed-off-by: Ben Greear <greearb@candelatech.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ben Greear 2011-02-11 09:35:18 +00:00 committed by David S. Miller
parent ab889e6607
commit 57f89bfa21
1 changed files with 29 additions and 2 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

31
net/packet/af_packet.c
View file

@ -465,7 +465,7 @@ static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
*/
err = -EMSGSIZE;
if (len > dev->mtu + dev->hard_header_len)
if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN)
goto out_unlock;
if (!skb) {
@ -496,6 +496,19 @@ static int packet_sendmsg_spkt(struct kiocb *iocb, struct socket *sock,
goto retry;
}
if (len > (dev->mtu + dev->hard_header_len)) {
/* Earlier code assumed this would be a VLAN pkt,
* double-check this now that we have the actual
* packet in hand.
*/
struct ethhdr *ehdr;
skb_reset_mac_header(skb);
ehdr = eth_hdr(skb);
if (ehdr->h_proto != htons(ETH_P_8021Q)) {
err = -EMSGSIZE;
goto out_unlock;
}
}
skb->protocol = proto;
skb->dev = dev;
@ -1199,7 +1212,7 @@ static int packet_snd(struct socket *sock,
}
err = -EMSGSIZE;
if (!gso_type && (len > dev->mtu+reserve))
if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN))
goto out_unlock;
err = -ENOBUFS;
@ -1224,6 +1237,20 @@ static int packet_snd(struct socket *sock,
if (err < 0)
goto out_free;
if (!gso_type && (len > dev->mtu + reserve)) {
/* Earlier code assumed this would be a VLAN pkt,
* double-check this now that we have the actual
* packet in hand.
*/
struct ethhdr *ehdr;
skb_reset_mac_header(skb);
ehdr = eth_hdr(skb);
if (ehdr->h_proto != htons(ETH_P_8021Q)) {
err = -EMSGSIZE;
goto out_free;
}
}
skb->protocol = proto;
skb->dev = dev;
skb->priority = sk->sk_priority;