CVE-2024-42108 (GCVE-0-2024-42108)
Vulnerability from cvelistv5
Published
2024-07-30 07:46
Modified
2026-08-05 11:35
Severity ?
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
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.
References
Impacted products
Vendor Product Version
Linux Linux Version: 0aeec4bb6a9fc963932bf3c929bdf27d835d44e9
Version: 271e015b91535dd87fd0f5df0cc3b906c2eddef9
Version: 271e015b91535dd87fd0f5df0cc3b906c2eddef9
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