CVE-2021-47327 - CVE House
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Status published Unknown CVE-2021-47327

iommu/arm-smmu: Fix arm_smmu_device refcount leak when arm_smmu_rpm_get fails

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu: Fix arm_smmu_device refcount leak when arm_smmu_rpm_get fails arm_smmu_rpm_get() invokes pm_runtime_get_sync(), which increases the refcount of the "smmu" even though the return value is less than 0. The reference counting issue happens in some error handling paths of arm_smmu_rpm_get() in its caller functions. When arm_smmu_rpm_get() fails, the caller functions forget to decrease the refcount of "smmu" increased by arm_smmu_rpm_get(), causing a refcount leak. Fix this issue by calling pm_runtime_resume_and_get() instead of pm_runtime_get_sync() in arm_smmu_rpm_get(), which can keep the refcount balanced in case of failure.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

Affected Vendor

Affected Software

Linux
Vulnerable Versions:
d4a44f0750bb9bf7c44c22444a482756b2344a79, 5.0, 0, 5.4.134, 5.10.52, 5.12.19, 5.13.4, 5.14

Timeline

Official Publish: May 21st, 2024
Last Modified: May 11th, 2026
Added to House: July 21st, 2026

CVSS Vectors

No vector data available

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.