| Message ID | 20200916164918.450933-1-xie.he.0141@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [net] drivers/net/wan/lapbether: Make skb->protocol consistent with the header | expand |
From: Xie He <xie.he.0141@gmail.com> Date: Wed, 16 Sep 2020 09:49:18 -0700 > 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> Applied, thank you.
diff --git a/drivers/net/wan/lapbether.c b/drivers/net/wan/lapbether.c index 732a6c1851f5..b6be2454b8bd 100644 --- a/drivers/net/wan/lapbether.c +++ b/drivers/net/wan/lapbether.c @@ -198,8 +198,6 @@ 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; @@ -210,6 +208,8 @@ 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);
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> --- drivers/net/wan/lapbether.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)