CVE-2021-47327
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.26%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.1 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
- EPSS
- 0.26% probability · 17th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-911
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/1adf30f198c26539a62d761e45af72cde570413dPatch
- https://git.kernel.org/stable/c/3761ae0d0e549f2acdaf11f49df4ed06d256b20fPatch
- https://git.kernel.org/stable/c/c4007596fbdabc29f858dc2e1990858a146b60b2Patch
- https://git.kernel.org/stable/c/fbf4daa6f4105e01fbd3868006f65c163365c1e3Patch
- https://git.kernel.org/stable/c/fe92c058199067ae90cf2a901ddf3c271893557aPatch
- https://git.kernel.org/stable/c/1adf30f198c26539a62d761e45af72cde570413dPatch
- https://git.kernel.org/stable/c/3761ae0d0e549f2acdaf11f49df4ed06d256b20fPatch
- https://git.kernel.org/stable/c/c4007596fbdabc29f858dc2e1990858a146b60b2Patch
- https://git.kernel.org/stable/c/fbf4daa6f4105e01fbd3868006f65c163365c1e3Patch
- https://git.kernel.org/stable/c/fe92c058199067ae90cf2a901ddf3c271893557aPatch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.