CVE-2022-48904

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

iommu/amd: Fix I/O page table memory leak

The current logic updates the I/O page table mode for the domain before calling the logic to free memory used for the page table. This results in IOMMU page table memory leak, and can be observed when launching VM w/ pass-through devices.

Fix by freeing the memory used for page table before updating the mode.

Weakness

The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory.

Affected Software

Potential Mitigations

• Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone.
• For example, glibc in Linux provides protection against free of invalid pointers.
• When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391].
• To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.

References

• https://git.kernel.org/stable/c/378e2fe1eb58d5c2ed55c8fe5e11f9db5033cdd6
• https://git.kernel.org/stable/c/6b0b2d9a6a308bcd9300c2d83000a82812c56cea
• https://git.kernel.org/stable/c/c78627f757e37c2cf386b59c700c4e1574988597