CyberRota Analysis
AI-GeneratedThe vulnerability affects the Linux kernel's memory management, specifically in the handling of folio mappings during the migration of device pages. An attacker could exploit this flaw to cause invalid reference accounting, potentially leading to a system crash due to a folio reference count error. Organizations using Linux-based systems, particularly those relying on memory migration features, should prioritize patching this vulnerability to maintain system stability and security.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: mm/migrate_device: clear stale mapping after freeing swapcache __migrate_device_pages() reads the folio mapping before calling folio_free_swap(). When folio_free_swap() succeeds, the folio is removed from the swap cache, but the saved mapping still points to swap_space. Passing the stale mapping to folio_migrate_mapping() makes it use the mapped-folio path for a folio that is no longer in swapcache. It can then operate on swap_space.i_pages with invalid reference accounting, eventually triggering a folio reference count BUG. After a successful split, nr still contains the number of pages in the original large folio, although each resulting page is now a separate order-0 folio. Reset nr to 1 so each split folio is processed separately, including its own swapcache removal and mapping lookup. Refresh the saved mapping after folio_free_swap() so the current folio state is used during migration.