Description

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

net: fix NULL pointer dereference in l3mdev_l3_rcv

When delete l3s ipvlan:

ip link del link eth0 ipvlan1 type ipvlan mode l3s

This may cause a null pointer dereference:

Call trace:
ip_rcv_finish+0x48/0xd0
ip_rcv+0x5c/0x100
__netif_receive_skb_one_core+0x64/0xb0
__netif_receive_skb+0x20/0x80
process_backlog+0xb4/0x204
napi_poll+0xe8/0x294
net_rx_action+0xd8/0x22c
__do_softirq+0x12c/0x354

This is because l3mdev_l3_rcv() visit dev->l3mdev_ops after
ipvlan_l3s_unregister() assign the dev->l3mdev_ops to NULL. The process
like this:

(CPU1) | (CPU2)
l3mdev_l3_rcv() |
check dev->priv_flags: |
master = skb->dev; |
|
| ipvlan_l3s_unregister()
| set dev->priv_flags
| dev->l3mdev_ops = NULL;
|
visit master->l3mdev_ops |

To avoid this by do not set dev->l3mdev_ops when unregister l3s ipvlan.

Classification

CVE ID: CVE-2025-22103

Affected Products

Vendor: Linux

Product: Linux, Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.02% (probability of being exploited)

EPSS Percentile: 3.26% (scored less or equal to compared to others)

EPSS Date: 2025-04-20 (when was this score calculated)

References

https://nvd.nist.gov/vuln/detail/CVE-2025-22103
https://git.kernel.org/stable/c/f9dff65140efc289f01bcf39c3ca66a8806b6132
https://git.kernel.org/stable/c/0032c99e83b9ce6d5995d65900aa4b6ffb501cce

Timeline