netdev - [PATCH v4 net-next 11/14] net: dsa: include bridge addresses which are local in the host fdb list

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: <20210628220011.1910096-12-olteanv@gmail.com>
Date:   Tue, 29 Jun 2021 01:00:08 +0300
From:   Vladimir Oltean <olteanv@...il.com>
To:     netdev@...r.kernel.org
Cc:     Andrew Lunn <andrew@...n.ch>,
        Florian Fainelli <f.fainelli@...il.com>,
        Vivien Didelot <vivien.didelot@...il.com>,
        Jiri Pirko <jiri@...nulli.us>,
        Ido Schimmel <idosch@...sch.org>,
        Tobias Waldekranz <tobias@...dekranz.com>,
        Roopa Prabhu <roopa@...dia.com>,
        Nikolay Aleksandrov <nikolay@...dia.com>,
        Vladimir Oltean <vladimir.oltean@....com>
Subject: [PATCH v4 net-next 11/14] net: dsa: include bridge addresses which are local in the host fdb list

From: Tobias Waldekranz <tobias@...dekranz.com>

The bridge automatically creates local (not forwarded) fdb entries
pointing towards physical ports with their interface MAC addresses.
For switchdev, the significance of these fdb entries is the exact
opposite of that of non-local entries: instead of sending these frame
outwards, we must send them inwards (towards the host).

NOTE: The bridge's own MAC address is also "local". If that address is
not shared with any port, the bridge's MAC is not be added by this
functionality - but the following commit takes care of that case.

NOTE 2: We mark these addresses as host-filtered regardless of the value
of ds->assisted_learning_on_cpu_port. This is because, as opposed to the
speculative logic done for dynamic address learning on foreign
interfaces, the local FDB entries are rather fixed, so there isn't any
risk of them migrating from one bridge port to another.

Signed-off-by: Tobias Waldekranz <tobias@...dekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@....com>
---
 net/dsa/slave.c | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index ea9a7c1ce83e..d006bd04f84a 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -2398,10 +2398,12 @@ static int dsa_slave_switchdev_event(struct notifier_block *unused,
 		fdb_info = ptr;
 
 		if (dsa_slave_dev_check(dev)) {
-			if (!fdb_info->added_by_user || fdb_info->is_local)
-				return NOTIFY_OK;
-
 			dp = dsa_slave_to_port(dev);
+
+			if (fdb_info->is_local)
+				host_addr = true;
+			else if (!fdb_info->added_by_user)
+				return NOTIFY_OK;
 		} else {
 			/* Snoop addresses added to foreign interfaces
 			 * bridged with us, or the bridge
@@ -2425,9 +2427,15 @@ static int dsa_slave_switchdev_event(struct notifier_block *unused,
 				return NOTIFY_DONE;
 
 			dp = p->dp;
-			host_addr = true;
+			host_addr = fdb_info->is_local;
 
-			if (!fdb_info->added_by_user &&
+			/* FDB entries learned by the software bridge should
+			 * be installed as host addresses only if the driver
+			 * requests assisted learning.
+			 * On the other hand, FDB entries for local termination
+			 * should always be installed.
+			 */
+			if (!fdb_info->added_by_user && !fdb_info->is_local &&
 			    !dp->ds->assisted_learning_on_cpu_port)
 				return NOTIFY_DONE;
 
-- 
2.25.1