Description (CNA)
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.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 336bf30eb76580b579dc711ded5d599d905c0217 before e7396d23f9d5739f56cf9ab430c3a169f5508394; affected 336bf30eb76580b579dc711ded5d599d905c0217 before ad97b9a55246eb940a26ac977f80892a395cabf9; affected 336bf30eb76580b579dc711ded5d599d905c0217 before 5edb9854f8df5428b40990a1c7d60507da5bd330; affected 336bf30eb76580b579dc711ded5d599d905c0217 before 526394af4e8ade89cacd1a9ce2b97712712fcc34; affected 336bf30eb76580b579dc711ded5d599d905c0217 before b75070823b89009f5123fd0e05a8e0c3d39937c1; affected 336bf30eb76580b579dc711ded5d599d905c0217 before 1b68efce6dd483d22f50d0d3800c4cfda14b1305; affected 336bf30eb76580b579dc711ded5d599d905c0217 before b7880cb166ab62c2409046b2347261abf701530e; affected ef792d6ce0db6a56e56743b1de1716a982c3b851; affected 5.9.9 before 5.10 |
| Linux / Linux | affected 5.10; unaffected 0 before 5.10; unaffected 5.10.249 through 5.10.*; unaffected 5.15.199 through 5.15.*; unaffected 6.1.162 through 6.1.*; unaffected 6.6.122 through 6.6.*; unaffected 6.12.68 through 6.12.*; unaffected 6.18.8 through 6.18.*; unaffected 6.19 through * |
CWE
No CWE identifiers supplied.
References
- 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
ADP enrichment
No English description supplied.
No references supplied.