Vulnerability-Lookup

FKIE_CVE-2026-43326

Vulnerability from fkie_nvd - Published: 2026-05-08 14:16 - Updated: 2026-05-15 18:06

Severity

5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: sched_ext: Fix SCX_KICK_WAIT deadlock by deferring wait to balance callback SCX_KICK_WAIT busy-waits in kick_cpus_irq_workfn() using smp_cond_load_acquire() until the target CPU's kick_sync advances. Because the irq_work runs in hardirq context, the waiting CPU cannot reschedule and its own kick_sync never advances. If multiple CPUs form a wait cycle, all CPUs deadlock. Replace the busy-wait in kick_cpus_irq_workfn() with resched_curr() to force the CPU through do_pick_task_scx(), which queues a balance callback to perform the wait. The balance callback drops the rq lock and enables IRQs following the sched_core_balance() pattern, so the CPU can process IPIs while waiting. The local CPU's kick_sync is advanced on entry to do_pick_task_scx() and continuously during the wait, ensuring any CPU that starts waiting for us sees the advancement and cannot form cyclic dependencies.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/415cb193bb9736f0e830286c72a6fa8eb2a9cc5c	Patch
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/c3a7903f65cf4c7fb0477eb0f8b94f326a47fe54	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

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  "lastModified": "2026-05-15T18:06:20.393",
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          "baseScore": 5.5,
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          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
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  ]
}

CVE-2026-43326 (GCVE-0-2026-43326)

Vulnerability from cvelistv5 – Published: 2026-05-08 13:31 – Updated: 2026-05-11 22:22

Title

sched_ext: Fix SCX_KICK_WAIT deadlock by deferring wait to balance callback

Summary

Severity

No CVSS data available.

Assigner

Linux

References

2 references

URL	Tags
https://git.kernel.org/stable/c/c3a7903f65cf4c7fb…
https://git.kernel.org/stable/c/415cb193bb9736f0e…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 90e55164dad42c6546b698c031697b224a320834 , < c3a7903f65cf4c7fb0477eb0f8b94f326a47fe54 (git) Affected: 90e55164dad42c6546b698c031697b224a320834 , < 415cb193bb9736f0e830286c72a6fa8eb2a9cc5c (git)
Linux	Linux	Affected: 6.12 Unaffected: 0 , < 6.12 (semver) Unaffected: 6.19.12 , ≤ 6.19.* (semver) Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

FKIE_CVE-2026-43326

CVE-2026-43326 (GCVE-0-2026-43326)

Tags

Sightings

Nomenclature