Re: [PATCH net-next] net, bonding: Disallow vlan+srcmac with XDP

On 12/08/2021 17:52, Jussi Maki wrote:

The new vlan+srcmac xmit policy is not implementable with XDP since
in many cases the 802.1Q payload is not present in the packet. This
can be for example due to hardware offload or in the case of veth
due to use of skbuffs internally.

This also fixes the NULL deref with the vlan+srcmac xmit policy
reported by Jonathan Toppins by additionally checking the skb
pointer.

Fixes: a815bde56b15 ("net, bonding: Refactor bond_xmit_hash for use with xdp_buff")
Reported-by: Jonathan Toppins <redacted>
Signed-off-by: Jussi Maki <redacted>
---
 drivers/net/bonding/bond_main.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

Hi Jussi,
Could you please share the null ptr deref trace?
I'm curious how we can get a null skb at that point.

Also how are the xdp and null ptr deref changes related ?

Thanks,
 Nik