CVE-2024-35993
Medium
Elevated severity or exploit probability.
CVSS breakdown
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
| Attack Vector | L | Local |
| Attack Complexity | L | Low |
| Privileges Required | L | Low |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | H | High |
| Integrity | H | High |
| Availability | H | High |
Timeline
- 2024-05-20 — Published (NVD)
- 2026-08-04 — Last modified (NVD)
Description
In the Linux kernel, the following vulnerability has been resolved: mm: turn folio_test_hugetlb into a PageType The current folio_test_hugetlb() can be fooled by a concurrent folio split into returning true for a folio which has never belonged to hugetlbfs. This can't happen if the caller holds a refcount on it, but we have a few places (memory-failure, compaction, procfs) which do not and should not take a speculative reference. Since hugetlb pages do not use individual page mapcounts (they are always fully mapped and use the entire_mapcount field to record the number of mappings), the PageType field is available now that page_mapcount() ignores the value in this field. In compaction and with CONFIG_DEBUG_VM enabled, the current implementation can result in an oops, as reported by Luis. This happens since 9c5ccf2db04b ("mm: remove HUGETLB_PAGE_DTOR") effectively added some VM_BUG_ON() checks in the PageHuge() testing path. [willy@infradead.org: update vmcoreinfo]
Affected
References
- https://git.kernel.org/stable/c/2431b5f2650dfc47ce782d1ca7b02d6b3916976f
- https://git.kernel.org/stable/c/9fdcc5b6359dfdaa52a55033bf50e2cedd66eb32
- https://git.kernel.org/stable/c/d99e3140a4d33e26066183ff727d8f02f56bec64
- https://git.kernel.org/stable/c/2431b5f2650dfc47ce782d1ca7b02d6b3916976f
- https://git.kernel.org/stable/c/9fdcc5b6359dfdaa52a55033bf50e2cedd66eb32
- https://git.kernel.org/stable/c/d99e3140a4d33e26066183ff727d8f02f56bec64