CVE-2024-26830

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

i40e: Do not allow untrusted VF to remove administratively set MAC

Currently when PF administratively sets VF's MAC address and the VF

is put down (VF tries to delete all MACs) then the MAC is removed

from MAC filters and primary VF MAC is zeroed.

Do not allow untrusted VF to remove primary MAC when it was set

administratively by PF.

Reproducer:

1) Create VF

2) Set VF interface up

3) Administratively set the VF's MAC

4) Put VF interface down

[root@host ~]# echo 1 > /sys/class/net/enp2s0f0/device/sriov_numvfs

[root@host ~]# ip link set enp2s0f0v0 up

[root@host ~]# ip link set enp2s0f0 vf 0 mac fe:6c:b5:da:c7:7d

[root@host ~]# ip link show enp2s0f0

23: enp2s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000

link/ether 3c:ec:ef:b7:dd:04 brd ff:ff:ff:ff:ff:ff

vf 0 link/ether fe:6c:b5:da:c7:7d brd ff:ff:ff:ff:ff:ff, spoof checking on, link-state auto, trus

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References