CVE-2026-46013
Description
In the Linux kernel, the following vulnerability has been resolved:
mm/memfd_luo: fix physical address conversion in put_folios cleanup
In memfd_luo_retrieve_folios()'s put_folios cleanup path:
1. kho_restore_folio() expects a phys_addr_t (physical address) but
receives a raw PFN (pfolio->pfn). This causes kho_restore_page() to
check the wrong physical address (pfn << PAGE_SHIFT instead of the
actual physical address).
2. This loop lacks the !pfolio->pfn check that exists in the main
retrieval loop and memfd_luo_discard_folios(), which could
incorrectly process sparse file holes where pfn=0.
Fix by converting PFN to physical address with PFN_PHYS() and adding
the !pfolio->pfn check, matching the pattern used elsewhere in this file.
This issue was identified by the AI review.
https://sashiko.dev/#/patchset/[email protected]