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 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 following products are affected by CVE-2021-47327 vulnerability.

Here, you will find a curated list of external links that provide in-depth information to CVE-2021-47327.

URL	Resource
https://git.kernel.org/stable/c/1adf30f198c26539a62d761e45af72cde570413d
https://git.kernel.org/stable/c/3761ae0d0e549f2acdaf11f49df4ed06d256b20f
https://git.kernel.org/stable/c/c4007596fbdabc29f858dc2e1990858a146b60b2
https://git.kernel.org/stable/c/fbf4daa6f4105e01fbd3868006f65c163365c1e3
https://git.kernel.org/stable/c/fe92c058199067ae90cf2a901ddf3c271893557a
https://lore.kernel.org/linux-cve-announce/2024052133-CVE-2021-47327-bbe1@gregkh/T
https://nvd.nist.gov/vuln/detail/CVE-2021-47327
https://www.cve.org/CVERecord?id=CVE-2021-47327