Bug 2461508 (CVE-2026-31574)

Summary: CVE-2026-31574 kernel: clockevents: Add missing resets of the next_event_forced flag
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's clock event handling. Missing resets of a critical flag can lead to timer interrupt starvation and system stalls. This vulnerability could allow an attacker to cause a denial of service (DoS) by making the system unresponsive.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-04-24 15:05:38 UTC
In the Linux kernel, the following vulnerability has been resolved:

clockevents: Add missing resets of the next_event_forced flag

The prevention mechanism against timer interrupt starvation missed to reset
the next_event_forced flag in a couple of places:

    - When the clock event state changes. That can cause the flag to be
      stale over a shutdown/startup sequence

    - When a non-forced event is armed, which then prevents rearming before
      that event. If that event is far out in the future this will cause
      missed timer interrupts.

    - In the suspend wakeup handler.

That led to stalls which have been reported by several people.

Add the missing resets, which fixes the problems for the reporters.