CVE-2026-43253

In the Linux kernel, the following vulnerability has been resolved: iommu/amd: move wait_on_sem() out of spinlock With iommu.strict=1, the existing completion wait path can cause soft lockups under stressed environment, as wait_on_sem() busy-waits under the spinlock with interrupts disabled. Move the completion wait in iommu_completion_wait() out of the spinlock. wait_on_sem() only polls the hardware-updated cmd_sem and does not require iommu->lock, so holding the lock during the busy wait unnecessarily increases contention and extends the time with interrupts disabled.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/496269d12072ecb219826485bdbec70c92a8eef5	Patch
https://git.kernel.org/stable/c/69d9339c02eddfc2a345be7220651068a3684383
https://git.kernel.org/stable/c/715c263119fd1b918a9fcbd8a36ea5b604a46324	Patch
https://git.kernel.org/stable/c/d2a0cac10597068567d336e85fa3cbdbe8ca62bf	Patch
https://git.kernel.org/stable/c/e15768e68820142077bbca402d8e902f64ade1b0	Patch
https://git.kernel.org/stable/c/f2f65b28d802a667119147444ec2ae33eebf9a58	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

30 Oct 2026, 13:18

Type	Values Removed	Values Added
References		() https://git.kernel.org/stable/c/69d9339c02eddfc2a345be7220651068a3684383 -

19 Oct 2026, 20:18

Type	Values Removed	Values Added
CWE		CWE-833

Information

Published : 2026-05-06 12:16

Updated : 2026-10-30 13:18

NVD link : CVE-2026-43253

Mitre link : CVE-2026-43253

CVE.ORG link : CVE-2026-43253

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-667

Improper Locking

CWE-833

Deadlock

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