net: dsa: tag_dsa: Allow forwarding of redirected IGMP traffic

When receiving an IGMP/MLD frame with a TO_CPU tag, the switch has not
performed any forwarding of it. This means that we should not set the
offload_fwd_mark on the skb, in case a software bridge wants it
forwarded.

This is a port of:

1ed9ec9b08 ("dsa: Allow forwarding of redirected IGMP traffic")

Which corrected the issue for chips using EDSA tags, but not for those
using regular DSA tags.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Tobias Waldekranz 2020-11-15 00:45:56 +01:00 committed by Jakub Kicinski
parent 72308ecbf3
commit e468d141b9

View file

@ -12,6 +12,11 @@
#define DSA_HLEN 4
#define FRAME_TYPE_TO_CPU 0x00
#define FRAME_TYPE_FORWARD 0x03
#define TO_CPU_CODE_IGMP_MLD_TRAP 0x02
static struct sk_buff *dsa_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct dsa_port *dp = dsa_slave_to_port(dev);
@ -61,6 +66,8 @@ static struct sk_buff *dsa_rcv(struct sk_buff *skb, struct net_device *dev,
u8 *dsa_header;
int source_device;
int source_port;
int frame_type;
int code;
if (unlikely(!pskb_may_pull(skb, DSA_HLEN)))
return NULL;
@ -73,8 +80,29 @@ static struct sk_buff *dsa_rcv(struct sk_buff *skb, struct net_device *dev,
/*
* Check that frame type is either TO_CPU or FORWARD.
*/
if ((dsa_header[0] & 0xc0) != 0x00 && (dsa_header[0] & 0xc0) != 0xc0)
frame_type = dsa_header[0] >> 6;
switch (frame_type) {
case FRAME_TYPE_TO_CPU:
code = (dsa_header[1] & 0x6) | ((dsa_header[2] >> 4) & 1);
/*
* Mark the frame to never egress on any port of the same switch
* unless it's a trapped IGMP/MLD packet, in which case the
* bridge might want to forward it.
*/
if (code != TO_CPU_CODE_IGMP_MLD_TRAP)
skb->offload_fwd_mark = 1;
break;
case FRAME_TYPE_FORWARD:
skb->offload_fwd_mark = 1;
break;
default:
return NULL;
}
/*
* Determine source device and port.
@ -132,8 +160,6 @@ static struct sk_buff *dsa_rcv(struct sk_buff *skb, struct net_device *dev,
2 * ETH_ALEN);
}
skb->offload_fwd_mark = 1;
return skb;
}