Description (CNA)
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.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected df263d9a7dffee94ca5391120ee3b0587efa07f1 before 92db780dd644590c751246187e1229d5ac2e5544; affected df263d9a7dffee94ca5391120ee3b0587efa07f1 before 4fa91f7bbc4135240b67daac03fc17d9e180a331; affected df263d9a7dffee94ca5391120ee3b0587efa07f1 before 8ffedc6573a665cdc31ebe47eae7b32b78d0df83; affected df263d9a7dffee94ca5391120ee3b0587efa07f1 before 34a00895d032a414830d41106a09329ae6c251b6 |
| Linux / Linux | affected 6.6; unaffected 0 before 6.6; unaffected 6.6.160 through 6.6.*; unaffected 6.12.111 through 6.12.*; unaffected 7.2.4 through 7.2.*; unaffected 7.3 through * |
CWE
No CWE identifiers supplied.