CVE-2023-52659

Source
https://nvd.nist.gov/vuln/detail/CVE-2023-52659
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-52659.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2023-52659
Downstream
Related
Published
2024-05-17T13:15:57Z
Modified
2025-09-25T15:54:17Z
Severity
  • 5.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
[none]
Details

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

x86/mm: Ensure input to pfntokaddr() is treated as a 64-bit type

On 64-bit platforms, the pfntokaddr() macro requires that the input value is 64 bits in order to ensure that valid address bits don't get lost when shifting that input by PAGE_SHIFT to calculate the physical address to provide a virtual address for.

One such example is in pvalidatepages() (used by SEV-SNP guests), where the GFN in the struct used for page-state change requests is a 40-bit bit-field, so attempts to pass this GFN field directly into pfnto_kaddr() ends up causing guest crashes when dealing with addresses above the 1TB range due to the above.

Fix this issue with SEV-SNP guests, as well as any similar cases that might cause issues in current/future code, by using an inline function, instead of a macro, so that the input is implicitly cast to the expected 64-bit input type prior to performing the shift operation.

While it might be argued that the issue is on the caller side, other archs/macros have taken similar approaches to deal with instances like this, such as ARM explicitly casting the input to physaddrt:

e48866647b48 ("ARM: 8396/1: use physaddrt in pfntokaddr()")

A C inline function is even better though.

[ mingo: Refined the changelog some more & added _alwaysinline. ]

References

Affected packages