netdev - [PATCH net 1/2] net: dsa: tag_8021q: Change order of rx

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20190528225005.10628-2-olteanv@gmail.com>
Date:   Wed, 29 May 2019 01:50:04 +0300
From:   Vladimir Oltean <olteanv@...il.com>
To:     f.fainelli@...il.com, vivien.didelot@...il.com, andrew@...n.ch,
        davem@...emloft.net
Cc:     ioana.ciornei@....com, netdev@...r.kernel.org,
        Vladimir Oltean <olteanv@...il.com>
Subject: [PATCH net 1/2] net: dsa: tag_8021q: Change order of rx_vid setup

From: Ioana Ciornei <ioana.ciornei@....com>

The 802.1Q tagging performs an unbalanced setup in terms of RX VIDs on
the CPU port. For the ingress path of a 802.1Q switch to work, the RX
VID of a port needs to be seen as tagged egress on the CPU port.

While configuring the other front-panel ports to be part of this VID,
for bridge scenarios, the untagged flag is applied even on the CPU port
in dsa_switch_vlan_add.  This happens because DSA applies the same flags
on the CPU port as on the (bridge-controlled) slave ports, and the
effect in this case is that the CPU port tagged settings get deleted.

Instead of fixing DSA by introducing a way to control VLAN flags on the
CPU port (and hence stop inheriting from the slave ports) - a hard,
perhaps intractable problem - avoid this situation by moving the setup
part of the RX VID on the CPU port after all the other front-panel ports
have been added to the VID.

Signed-off-by: Ioana Ciornei <ioana.ciornei@....com>
Signed-off-by: Vladimir Oltean <olteanv@...il.com>
Fixes: f9bbe4477c30 ("net: dsa: Optional VLAN-based port separation for switches without tagging")
---
 net/dsa/tag_8021q.c | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/net/dsa/tag_8021q.c b/net/dsa/tag_8021q.c
index 8ae48c7e1e76..4adec6bbfe59 100644
--- a/net/dsa/tag_8021q.c
+++ b/net/dsa/tag_8021q.c
@@ -128,10 +128,7 @@ int dsa_port_setup_8021q_tagging(struct dsa_switch *ds, int port, bool enabled)
 		u16 flags;

 		if (i == upstream)
-			/* CPU port needs to see this port's RX VID
-			 * as tagged egress.
-			 */
-			flags = 0;
+			continue;
 		else if (i == port)
 			/* The RX VID is pvid on this port */
 			flags = BRIDGE_VLAN_INFO_UNTAGGED |
@@ -150,6 +147,20 @@ int dsa_port_setup_8021q_tagging(struct dsa_switch *ds, int port, bool enabled)
 			return err;
 		}
 	}
+
+	/* CPU port needs to see this port's RX VID
+	 * as tagged egress.
+	 */
+	if (enabled)
+		err = dsa_port_vid_add(upstream_dp, rx_vid, 0);
+	else
+		err = dsa_port_vid_del(upstream_dp, rx_vid);
+	if (err) {
+		dev_err(ds->dev, "Failed to apply RX VID %d to port %d: %d\n",
+			rx_vid, port, err);
+		return err;
+	}
+
 	/* Finally apply the TX VID on this port and on the CPU port */
 	if (enabled)
 		err = dsa_port_vid_add(dp, tx_vid, BRIDGE_VLAN_INFO_UNTAGGED);
-- 
2.17.1