From: Vladimir Oltean vladimir.oltean@nxp.com
[ Upstream commit c1ae02d876898b1b8ca1e12c6f84d7b406263800 ]
Currently the sja1105 tagging protocol prefers using the source port information from the VLAN header if that is available, falling back to the INCL_SRCPT option if it isn't. The VLAN header is available for all frames except for META frames initiated by the switch (containing RX timestamps), and thus, the "if (is_link_local)" branch is practically dead.
The tag_8021q source port identification has become more loose ("imprecise") and will report a plausible rather than exact bridge port, when under a bridge (be it VLAN-aware or VLAN-unaware). But link-local traffic always needs to know the precise source port. With incorrect source port reporting, for example PTP traffic over 2 bridged ports will all be seen on sockets opened on the first such port, which is incorrect.
Now that the tagging protocol has been changed to make link-local frames always contain source port information, we can reverse the order of the checks so that we always give precedence to that information (which is always precise) in lieu of the tag_8021q VID which is only precise for a standalone port.
Fixes: d7f9787a763f ("net: dsa: tag_8021q: add support for imprecise RX based on the VBID") Fixes: 91495f21fcec ("net: dsa: tag_8021q: replace the SVL bridging with VLAN-unaware IVL bridging") Signed-off-by: Vladimir Oltean vladimir.oltean@nxp.com Reviewed-by: Simon Horman simon.horman@corigine.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/dsa/tag_sja1105.c | 38 +++++++++++++++++++++++++++++--------- 1 file changed, 29 insertions(+), 9 deletions(-)
diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c index 1a85125bda6da..731dc3a111ef3 100644 --- a/net/dsa/tag_sja1105.c +++ b/net/dsa/tag_sja1105.c @@ -540,10 +540,7 @@ static struct sk_buff *sja1105_rcv(struct sk_buff *skb, is_link_local = sja1105_is_link_local(skb); is_meta = sja1105_is_meta_frame(skb);
- if (sja1105_skb_has_tag_8021q(skb)) { - /* Normal traffic path. */ - sja1105_vlan_rcv(skb, &source_port, &switch_id, &vbid, &vid); - } else if (is_link_local) { + if (is_link_local) { /* Management traffic path. Switch embeds the switch ID and * port ID into bytes of the destination MAC, courtesy of * the incl_srcpt options. @@ -557,16 +554,39 @@ static struct sk_buff *sja1105_rcv(struct sk_buff *skb, sja1105_meta_unpack(skb, &meta); source_port = meta.source_port; switch_id = meta.switch_id; - } else { + } + + /* Normal data plane traffic and link-local frames are tagged with + * a tag_8021q VLAN which we have to strip + */ + if (sja1105_skb_has_tag_8021q(skb)) { + int tmp_source_port = -1, tmp_switch_id = -1; + + sja1105_vlan_rcv(skb, &tmp_source_port, &tmp_switch_id, &vbid, + &vid); + /* Preserve the source information from the INCL_SRCPT option, + * if available. This allows us to not overwrite a valid source + * port and switch ID with zeroes when receiving link-local + * frames from a VLAN-unaware bridged port (non-zero vbid) or a + * VLAN-aware bridged port (non-zero vid). + */ + if (source_port == -1) + source_port = tmp_source_port; + if (switch_id == -1) + switch_id = tmp_switch_id; + } else if (source_port == -1 && switch_id == -1) { + /* Packets with no source information have no chance of + * getting accepted, drop them straight away. + */ return NULL; }
- if (vbid >= 1) + if (source_port != -1 && switch_id != -1) + skb->dev = dsa_master_find_slave(netdev, switch_id, source_port); + else if (vbid >= 1) skb->dev = dsa_tag_8021q_find_port_by_vbid(netdev, vbid); - else if (source_port == -1 || switch_id == -1) - skb->dev = dsa_find_designated_bridge_port_by_vid(netdev, vid); else - skb->dev = dsa_master_find_slave(netdev, switch_id, source_port); + skb->dev = dsa_find_designated_bridge_port_by_vid(netdev, vid); if (!skb->dev) { netdev_warn(netdev, "Couldn't decode source port\n"); return NULL;