From: Xie He xie.he.0141@gmail.com
[ Upstream commit 83f9a9c8c1edc222846dc1bde6e3479703e8e5a3 ]
This driver is a virtual driver stacked on top of Ethernet interfaces.
When this driver transmits data on the Ethernet device, the skb->protocol setting is inconsistent with the Ethernet header prepended to the skb.
This causes a user listening on the Ethernet interface with an AF_PACKET socket, to see different sll_protocol values for incoming and outgoing frames, because incoming frames would have this value set by parsing the Ethernet header.
This patch changes the skb->protocol value for outgoing Ethernet frames, making it consistent with the Ethernet header prepended. This makes a user listening on the Ethernet device with an AF_PACKET socket, to see the same sll_protocol value for incoming and outgoing frames.
Cc: Martin Schiller ms@dev.tdt.de Signed-off-by: Xie He xie.he.0141@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wan/lapbether.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/net/wan/lapbether.c b/drivers/net/wan/lapbether.c index 15177a54b17d7..e5fc1b95cea6a 100644 --- a/drivers/net/wan/lapbether.c +++ b/drivers/net/wan/lapbether.c @@ -201,8 +201,6 @@ static void lapbeth_data_transmit(struct net_device *ndev, struct sk_buff *skb) struct net_device *dev; int size = skb->len;
- skb->protocol = htons(ETH_P_X25); - ptr = skb_push(skb, 2);
*ptr++ = size % 256; @@ -213,6 +211,8 @@ static void lapbeth_data_transmit(struct net_device *ndev, struct sk_buff *skb)
skb->dev = dev = lapbeth->ethdev;
+ skb->protocol = htons(ETH_P_DEC); + skb_reset_network_header(skb);
dev_hard_header(skb, dev, ETH_P_DEC, bcast_addr, NULL, 0);