From a9157077bb1b8a1b9f081af71c4f21a41ad7f9f5 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Mon, 24 May 2021 12:25:27 +0300 Subject: [PATCH] net: dsa: sja1105: update existing VLANs from the bridge VLAN list commit b38e659de966a122fe2cb178c1e39c9bea06bc62 upstream. When running this sequence of operations: ip link add br0 type bridge vlan_filtering 1 ip link set swp4 master br0 bridge vlan add dev swp4 vid 1 We observe the traffic sent on swp4 is still untagged, even though the bridge has overwritten the existing VLAN entry: port vlan ids swp4 1 PVID br0 1 PVID Egress Untagged This happens because we didn't consider that the 'bridge vlan add' command just overwrites VLANs like it's nothing. We treat the 'vid 1 pvid untagged' and the 'vid 1' as two separate VLANs, and the first still has precedence when calling sja1105_build_vlan_table. Obviously there is a disagreement regarding semantics, and we end up doing something unexpected from the PoV of the bridge. Let's actually consider an "existing VLAN" to be one which is on the same port, and has the same VLAN ID, as one we already have, and update it if it has different flags than we do. The first blamed commit is the one introducing the bug, the second one is the latest on top of which the bugfix still applies. Fixes: ec5ae61076d0 ("net: dsa: sja1105: save/restore VLANs using a delta commit method") Fixes: 5899ee367ab3 ("net: dsa: tag_8021q: add a context structure") Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/dsa/sja1105/sja1105_main.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c index 51ea104c63bbb..0f27bf79d08ee 100644 --- a/drivers/net/dsa/sja1105/sja1105_main.c +++ b/drivers/net/dsa/sja1105/sja1105_main.c @@ -2817,11 +2817,22 @@ static int sja1105_vlan_add_one(struct dsa_switch *ds, int port, u16 vid, bool pvid = flags & BRIDGE_VLAN_INFO_PVID; struct sja1105_bridge_vlan *v; - list_for_each_entry(v, vlan_list, list) - if (v->port == port && v->vid == vid && - v->untagged == untagged && v->pvid == pvid) + list_for_each_entry(v, vlan_list, list) { + if (v->port == port && v->vid == vid) { /* Already added */ - return 0; + if (v->untagged == untagged && v->pvid == pvid) + /* Nothing changed */ + return 0; + + /* It's the same VLAN, but some of the flags changed + * and the user did not bother to delete it first. + * Update it and trigger sja1105_build_vlan_table. + */ + v->untagged = untagged; + v->pvid = pvid; + return 1; + } + } v = kzalloc(sizeof(*v), GFP_KERNEL); if (!v) {