netdev - [PATCH v3 net-next 14/15] net: dsa: tag_sja1105: use a custom flow dissector procedure

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]

Date:   Sat, 26 Sep 2020 22:32:14 +0300
From:   Vladimir Oltean <vladimir.oltean@....com>
To:     netdev@...r.kernel.org, davem@...emloft.net
Cc:     andrew@...n.ch, f.fainelli@...il.com, vivien.didelot@...il.com,
        kuba@...nel.org
Subject: [PATCH v3 net-next 14/15] net: dsa: tag_sja1105: use a custom flow dissector procedure

The sja1105 is a bit of a special snowflake, in that not all frames are
transmitted/received in the same way. L2 link-local frames are received
with the source port/switch ID information put in the destination MAC
address. For the rest, a tag_8021q header is used. So only the latter
frames displace the rest of the headers and need to use the generic flow
dissector procedure.

Signed-off-by: Vladimir Oltean <vladimir.oltean@....com>
---
Changes in v3:
None.

 net/dsa/tag_sja1105.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c
index 36ebd5878061..50496013cdb7 100644
--- a/net/dsa/tag_sja1105.c
+++ b/net/dsa/tag_sja1105.c
@@ -346,6 +346,16 @@ static struct sk_buff *sja1105_rcv(struct sk_buff *skb,
 					      is_meta);
 }
 
+static void sja1105_flow_dissect(const struct sk_buff *skb, __be16 *proto,
+				 int *offset)
+{
+	/* No tag added for management frames, all ok */
+	if (unlikely(sja1105_is_link_local(skb)))
+		return;
+
+	dsa_tag_generic_flow_dissect(skb, proto, offset);
+}
+
 static const struct dsa_device_ops sja1105_netdev_ops = {
 	.name = "sja1105",
 	.proto = DSA_TAG_PROTO_SJA1105,
@@ -353,6 +363,7 @@ static const struct dsa_device_ops sja1105_netdev_ops = {
 	.rcv = sja1105_rcv,
 	.filter = sja1105_filter,
 	.overhead = VLAN_HLEN,
+	.flow_dissect = sja1105_flow_dissect,
 	.promisc_on_master = true,
 };
 
-- 
2.25.1