CyberRota Analysis
AI-GeneratedThe vulnerability affects the Linux kernel's AMD IOMMU implementation, specifically in the handling of nested domain allocation where an error check is ineffective due to improper type handling. This oversight can lead to the allocation of an invalid host domain ID, potentially compromising system stability and security. Organizations utilizing Linux systems with AMD hardware should prioritize addressing this issue to prevent potential exploitation.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: iommu/amd: Fix ineffective error check in nested domain allocation amd_iommu_pdom_id_alloc() returns an int: a domain ID on success, or the negative errno from ida_alloc_range() when the ID space is exhausted or memory is short. amd_iommu_alloc_domain_nested() stores that return value in gdom_info->hdom_id, which is a u32, and only then tests it: gdom_info->hdom_id = amd_iommu_pdom_id_alloc(); if (gdom_info->hdom_id <= 0) { The assignment discards the sign, so -ENOSPC becomes 0xffffffe4 and the test never fires. The nested domain is then set up with a host domain ID that was never allocated, instead of the allocation failing with -ENOSPC. Keep the value in an int, test it there, and store it only once it is known to be valid, which is what the other amd_iommu_pdom_id_alloc() callers already do.