CVE-2021-47327

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

High · published May 21, 2024

CVSS v3.1
7.1
EPSS
0%
Percentile
16.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
7.1 · HIGH
Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00255 · 16.2th percentile
Published
2024-05-21T14:35Z
EPSS history
Timeline
  • 21 MAY 14:35Z
    iommu/arm-smmu: Fix arm_smmu_device refcount leak when arm_smmu_rpm_get fails
    cvelistv5