CVE-2025-71202

Summary

In the Linux kernel, the following vulnerability has been resolved:

iommu/sva: invalidate stale IOTLB entries for kernel address space

Introduce a new IOMMU interface to flush IOTLB paging cache entries for the CPU kernel address space. This interface is invoked from the x86 architecture code that manages combined user and kernel page tables, specifically before any kernel page table page is freed and reused.

This addresses the main issue with vfree() which is a common occurrence and can be triggered by unprivileged users. While this resolves the primary problem, it doesn't address some extremely rare case related to memory unplug of memory that was present as reserved memory at boot, which cannot be triggered by unprivileged users. The discussion can be found at the link below.

Enable SVA on x86 architecture since the IOMMU can now receive notification to flush the paging cache before freeing the CPU kernel page table pages.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux2f26e0a9c9860db290d63e9d85c2c8c09813677f < 9f0a7ab700f8620e433b05c57fbd26c92ea186d9affected
LinuxLinux2f26e0a9c9860db290d63e9d85c2c8c09813677f < e37d5a2d60a338c5917c45296bac65da1382eda5affected
LinuxLinux4.4affected
LinuxLinux0 < 4.4unaffected
LinuxLinux6.18.7 <= 6.18.*unaffected
LinuxLinux6.19 <= *unaffected

Weaknesses

References