CVE-2026-23097

Description

In the Linux kernel, the following vulnerability has been resolved: migrate: correct lock ordering for hugetlb file folios Syzbot has found a deadlock (analyzed by Lance Yang): 1) Task (5749): Holds folio_lock, then tries to acquire i_mmap_rwsem(read lock). 2) Task (5754): Holds i_mmap_rwsem(write lock), then tries to acquire folio_lock. migrate_pages() -> migrate_hugetlbs() -> unmap_and_move_huge_page() <- Takes folio_lock! -> remove_migration_ptes() -> __rmap_walk_file() -> i_mmap_lock_read() <- Waits for i_mmap_rwsem(read lock)! hugetlbfs_fallocate() -> hugetlbfs_punch_hole() <- Takes i_mmap_rwsem(write lock)! -> hugetlbfs_zero_partial_page() -> filemap_lock_hugetlb_folio() -> filemap_lock_folio() -> __filemap_get_folio <- Waits for folio_lock! The migration path is the one taking locks in the wrong order according to the documentation at the top of mm/rmap.c. So expand the scope of the existing i_mmap_lock to cover the calls to remove_migration_ptes() too. This is (mostly) how it used to be after commit c0d0381ade79. That was removed by 336bf30eb765 for both file & anon hugetlb pages when it should only have been removed for anon hugetlb pages.

Gravité et risque d'exploitation

CVE-2026-23097 obtient un score CVSS de 0.0/10, soit une gravité non évaluée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.13 %, ce qui la place devant 2.6 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <=6.1.*, <=6.12.*, <1b68efce6dd483d22f50d0d3800c4cfda14b1305, 0, <e7396d23f9d5739f56cf9ab430c3a169f5508394, 5.15.199, <b7880cb166ab62c2409046b2347261abf701530e, <526394af4e8ade89cacd1a9ce2b97712712fcc34, <=5.10.*, <=6.6.*, <5edb9854f8df5428b40990a1c7d60507da5bd330, 336bf30eb76580b579dc711ded5d599d905c0217, 5.10.249, 6.18.8, <5.10, 6.1.162, <=6.18.*, <b75070823b89009f5123fd0e05a8e0c3d39937c1, ef792d6ce0db6a56e56743b1de1716a982c3b851, 6.12.68, <=*, <ad97b9a55246eb940a26ac977f80892a395cabf9, <=5.15.*, 6.19, 6.6.122, 5.9.9, 5.10) est présent sur votre parc.
• Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
• À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
• Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.

Références

• https://git.kernel.org/stable/c/e7396d23f9d5739f56cf9ab430c3a169f5508394
• https://git.kernel.org/stable/c/ad97b9a55246eb940a26ac977f80892a395cabf9
• https://git.kernel.org/stable/c/5edb9854f8df5428b40990a1c7d60507da5bd330
• https://git.kernel.org/stable/c/526394af4e8ade89cacd1a9ce2b97712712fcc34
• https://git.kernel.org/stable/c/b75070823b89009f5123fd0e05a8e0c3d39937c1
• https://git.kernel.org/stable/c/1b68efce6dd483d22f50d0d3800c4cfda14b1305
• https://git.kernel.org/stable/c/b7880cb166ab62c2409046b2347261abf701530e