Re:Re: [PATCH v2] team: reject CAN and IEEE 802.15.4 devices in team_port_add

[jiale yao]

How about adding a helper in include/linux/if_arp.h, similar to dev_is_mac_header_xmit()? Perhaps
something like dev_is_can_or_ieee802154()?


At 2026-07-29 17:15:06, "Jiri Pirko" <jiri@xxxxxxxxxxx> wrote:
>Tue, Jul 28, 2026 at 05:12:40PM +0200, yaojiale02@xxxxxxx wrote:
>>Enslaving a CAN or IEEE 802.15.4 device (e.g. vxcan, wpan0) to a
>>team master triggers a NULL pointer dereference because these
>>device types use different Layer 2 architectures from Ethernet and
>>the team driver never initializes their private mid-layer data
>>structures.
>>
>>Reject ARPHRD_CAN, ARPHRD_IEEE802154, and ARPHRD_IEEE802154_MONITOR
>>devices in team_port_add(), mirroring the existing CAN check already
>>present in the bonding driver since commit 8ba68464e478 ("bonding:
>>refuse to enslave CAN devices").
>
>Can we perhaps have a unified helper for the check?
>
>
>>
>>Link: https://lore.kernel.org/all/b58d98e0-8fe3-4e4e-b8a5-c1c7e647ccca@xxxxxxxxxxxx/
>>Fixes: 1d76efe1577b ("team: add support for non-ethernet devices")
>>Assisted-by: Claude:deepseek-v4-pro
>
>Looks your ai gone a bit wild here...
>
>
>>Signed-off-by: Jiale Yao <yaojiale02@xxxxxxx>
>>---
>>V1 -> V2: Extended check to also reject ARPHRD_IEEE802154 and
>>  ARPHRD_IEEE802154_MONITOR devices per review feedback
>>---
>> drivers/net/team/team_core.c | 11 +++++++++++
>> 1 file changed, 11 insertions(+)
>>
>>diff --git a/drivers/net/team/team_core.c b/drivers/net/team/team_core.c
>>index feaa75fbf8fc..d8c46105fc8b 100644
>>--- a/drivers/net/team/team_core.c
>>+++ b/drivers/net/team/team_core.c
>>@@ -1224,6 +1224,17 @@ static int team_port_add(struct team *team, struct net_device *port_dev,
>> 		return -EINVAL;
>> 	}
>> 
>>+		if (port_dev->type == ARPHRD_CAN ||
>>+		    port_dev->type == ARPHRD_IEEE802154 ||
>>+		    port_dev->type == ARPHRD_IEEE802154_MONITOR) {
>>+			NL_SET_ERR_MSG(extack,
>>+				       "CAN and IEEE 802.15.4 devices can't be added as a team port");
>>+			netdev_err(dev, "Device %s is CAN or IEEE 802.15.4. These device types can't be added as a team port\n",
>>+				   portname);
>>+			return -EINVAL;
>>+		}
>>+	}
>>+
>> 	if (netif_is_team_port(port_dev)) {
>> 		NL_SET_ERR_MSG(extack, "Device is already a port of a team device");
>> 		netdev_err(dev, "Device %s is already a port "
>>-- 
>>2.34.1
>>