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.
OS | Version | Architecture | Package | Version | Filename |
---|---|---|---|---|---|
ubuntu | 24.04 | noarch | linux | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-aws | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-azure | < any | UNKNOWN |
ubuntu | 20.04 | noarch | linux-bluefield | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-gcp | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-gke | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-ibm | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-lowlatency | < any | UNKNOWN |
ubuntu | 24.04 | noarch | linux-nvidia | < any | UNKNOWN |
ubuntu | 22.04 | noarch | linux-nvidia-6.8 | < any | UNKNOWN |
git.kernel.org/linus/9a0c28efeec6383ef22e97437616b920e7320b67 (6.10-rc7)
git.kernel.org/stable/c/92cbbe7759193e3418f38d0d73f8fe125312c58b
git.kernel.org/stable/c/9a0c28efeec6383ef22e97437616b920e7320b67
launchpad.net/bugs/cve/CVE-2024-42108
nvd.nist.gov/vuln/detail/CVE-2024-42108
security-tracker.debian.org/tracker/CVE-2024-42108
www.cve.org/CVERecord?id=CVE-2024-42108