| From 698f7ab2fdba603f87ec0ed48b1f9aa8d3ce68c7 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Wed, 16 Sep 2020 09:49:18 -0700 |
| Subject: drivers/net/wan/lapbether: Make skb->protocol consistent with the |
| header |
| |
| 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); |
| -- |
| 2.25.1 |
| |
