In the Linux kernel, the following vulnerability has been resolved: io_uring/napi: cap busy_poll_to 10 msec Currently there's no cap on the maximum amount of time that napi is allowed to poll if no events are found, which can lead to kernel complaints on a task being stuck as there's no conditional rescheduling done within that loop. Just cap it to 10 msec in total, that's already way above any kind of sane value that will reap any benefits, yet low enough that it's nowhere near being able to trigger preemption complaints.

A flaw was found in the Linux kernel's io_uring subsystem, specifically in the Networked Asynchronous Packet Interface (NAPI) busy polling. This vulnerability allows NAPI to poll indefinitely for events when none are present, which can cause a task to become stuck. This can lead to a Denial of Service (DoS) condition, making the system unresponsive. The issue is addressed by implementing a 10-millisecond cap on the busy polling duration.

Red Hat Enterprise Linux 10 Fix deferred kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Fix deferred kernel Red Hat Enterprise Linux 9 Fix deferred kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-53321 https://nvd.nist.gov/vuln/detail/CVE-2026-53321 https://lore.kernel.org/linux-cve-announce/2026062622-CVE-2026-53321-d475@gregkh/T