From e468d141b993ec9e58bdf515ed32fd9eb4fccdd0 Mon Sep 17 00:00:00 2001 From: Tobias Waldekranz Date: Sun, 15 Nov 2020 00:45:56 +0100 Subject: [PATCH] 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: 1ed9ec9b08ad ("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 Reviewed-by: Andrew Lunn Reviewed-by: Florian Fainelli Signed-off-by: Jakub Kicinski --- net/dsa/tag_dsa.c | 32 +++++++++++++++++++++++++++++--- 1 file changed, 29 insertions(+), 3 deletions(-) diff --git a/net/dsa/tag_dsa.c b/net/dsa/tag_dsa.c index 63d690a0fca6..af340a4945dc 100644 --- a/net/dsa/tag_dsa.c +++ b/net/dsa/tag_dsa.c @@ -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; }