CVE Published: 30/07/2024 |
CVE Updated: 05/11/2024 |
CVE Year: 2024 Source: Linux |
Vendor: Linux |
Product: Linux Status : PUBLISHED
CVE-2024-42108 Description
In the Linux kernel, the following vulnerability has been resolved:
net: rswitch: Avoid use-after-free in rswitch_poll()
The use-after-free is actually in rswitch_tx_free(), which is inlined in
rswitch_poll(). Since `skb` and `gq->skbs[gq->dirty]` are in fact the
same pointer, the skb is first freed using dev_kfree_skb_any(), then the
value in skb->len is used to update the interface statistics.
Let\'s move around the instructions to use skb->len before the skb is
freed.
This bug is trivial to reproduce using KFENCE. It will trigger a splat
every few packets. A simple ARP request or ICMP echo request is enough.