Linux Kernel Vulnerability Affecting io_uring/napi Polling Mechanism

CVE-2026-53321

What is CVE-2026-53321?

A vulnerability exists in the Linux kernel related to the io_uring and napi subsystems, where there is no cap on the time allowed for napi to poll when no events are detected. This indefinite polling could lead to kernel issues indicating that the task is stuck. Implementing a cap of 10 milliseconds for this polling mechanism resolves the problem, ensuring that it remains within acceptable limits to avoid triggering preemption complaints while still functioning effectively.

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