| The vulnerability is in the MediaTek IOMMU driver in the Linux kernel. Specifically, in the `mtk_iommu_runtime_resume` function, the clock (clk) is not always enabled when resuming from suspend mode. This can cause a warning message to be printed, indicating that the clk is already disabled. |
| |
| The issue occurs because the `m4u_dom` pointer may be null, and if so, the clk is not enabled. To fix this, the clk should always be enabled in the `mtk_iommu_runtime_resume` function, even if `m4u_dom` is null. |
| |
| Additionally, the clock enablement from the `mtk_iommu_hw_init` function is no longer needed since it is already enabled by the resume path. |
| |
| This vulnerability was introduced in kernel version 5.12 and fixed in versions 5.12.4 and 5.13. The affected file is `drivers/iommu/mtk_iommu.c`. The Linux kernel CVE team recommends updating to the latest stable kernel version to fix this issue, as well as other bugfixes. |
| |
