Reset MAC header in HSR Tx path. This is needed, because direct packet
transmission, e.g. by specifying PACKET_QDISC_BYPASS does not reset the MAC
header.
This has been observed using the following setup:
|$ ip link add name hsr0 type hsr slave1 lan0 slave2 lan1 supervision 45
version 1
|$ ifconfig hsr0 up
|$ ./test hsr0
The test binary is using mmap'ed sockets and is specifying the
PACKET_QDISC_BYPASS socket option.
This patch resolves the following warning on a non-patched kernel:
|[ 112.725394] ------------[ cut here ]------------
|[ 112.731418] WARNING: CPU: 1 PID: 257 at net/hsr/hsr_forward.c:560
hsr_forward_skb+0x484/0x568
|[ 112.739962] net/hsr/hsr_forward.c:560: Malformed frame (port_src hsr0)
The warning can be safely removed, because the other call sites of
hsr_forward_skb() make sure that the skb is prepared correctly.
Fixes: d346a3fae3ff ("packet: introduce PACKET_QDISC_BYPASS socket option")
Signed-off-by: Kurt Kanzenbach <k...@linutronix.de>
---
Changes since v2:
* Move skb_reset_mac_header() to hsr_dev_xmit()
* Remove HSR malformed frame warning
Changes since v1:
* Move skb_reset_mac_header() to __dev_direct_xmit()
* Add Fixes tag
* Target net tree
Previous versions:
* https://lkml.kernel.org/netdev/20210329071716.12235-1-k...@linutronix.de/
* https://lkml.kernel.org/netdev/20210326154835.21296-1-k...@linutronix.de/
net/hsr/hsr_device.c | 1 +
net/hsr/hsr_forward.c | 6 ------
2 files changed, 1 insertion(+), 6 deletions(-)
diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c
index 7444ec6e298e..bfcdc75fc01e 100644
--- a/net/hsr/hsr_device.c
+++ b/net/hsr/hsr_device.c
@@ -217,6 +217,7 @@ static netdev_tx_t hsr_dev_xmit(struct sk_buff *skb, struct
net_device *dev)
master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
if (master) {
skb->dev = master->dev;
+ skb_reset_mac_header(skb);
hsr_forward_skb(skb, master);
} else {
atomic_long_inc(&dev->tx_dropped);
diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c
index ed82a470b6e1..b218e4594009 100644
--- a/net/hsr/hsr_forward.c
+++ b/net/hsr/hsr_forward.c
@@ -555,12 +555,6 @@ void hsr_forward_skb(struct sk_buff *skb, struct hsr_port
*port)
{
struct hsr_frame_info frame;
- if (skb_mac_header(skb) != skb->data) {
- WARN_ONCE(1, "%s:%d: Malformed frame (port_src %s)\n",
- __FILE__, __LINE__, port->dev->name);
- goto out_drop;
- }
-
if (fill_frame_info(&frame, skb, port) < 0)
goto out_drop;
--
2.20.1
