CVE-2025-68169

/// Technical description

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

netpoll: Fix deadlock in memory allocation under spinlock

Fix a AA deadlock in refill_skbs() where memory allocation while holding

skb_pool->lock can trigger a recursive lock acquisition attempt.

The deadlock scenario occurs when the system is under severe memory

pressure:

1. refill_skbs() acquires skb_pool->lock (spinlock)

2. alloc_skb() is called while holding the lock

3. Memory allocator fails and calls slab_out_of_memory()

4. This triggers printk() for the OOM warning

5. The console output path calls netpoll_send_udp()

6. netpoll_send_udp() attempts to acquire the same skb_pool->lock

7. Deadlock: the lock is already held by the same CPU

Call stack:

refill_skbs()

spin_lock_irqsave(&skb_pool->lock) <- lock acquired

__alloc_skb()

kmem_cache_alloc_node_noprof()

slab_out_of_memory()

printk()

console_flush_all()

netpoll_send_udp()

skb_deq

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References