CVE-2021-47327

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.

CVSS Score

Affected Products

Related Weaknesses (CWE)

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