Host denial of service via locked SKB free
Published Dec 7, 2022 · Updated Apr 23, 2025
Improper locking in the Linux xen-netback driver allows guest OS users to deadlock a host through a paravirtualized network interface. In xenvif_rx_queue_tail, a full receive queue causes kfree_skb() to run inside spin_lock_irqsave(), where freeing the packet with interrupts disabled can re-enter netpoll and deadlock. The flaw requires netpoll to be active on the interface connected to xen-netback; a malicious guest can hang the host.
Summary
What happened
Improper locking in the Linux xen-netback driver allows guest OS users to deadlock a host through a paravirtualized network interface. In xenvif_rx_queue_tail, a full receive queue causes kfree_skb() to run inside spin_lock_irqsave(), where freeing the packet with interrupts disabled can re-enter netpoll and deadlock. The flaw requires netpoll to be active on the interface connected to xen-netback; a malicious guest can hang the host.
The record
- CVE
- CVE-2022-42329
- Published
- Dec 7, 2022
- Updated
- Apr 23, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-667, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Dec 7, 2022CVE publishedPublication date reported by the CVE source.
- Apr 23, 2025Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
Affected products and versions are unavailable in this record.
Attacks
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Public exploit references
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Technologies
Your stack
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