---
id: CVE-2026-23097
title: 'migrate: correct lock ordering for hugetlb file folios'
summary: |-
  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…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 <
    e7396d23f9d5739f56cf9ab430c3a169f5508394
  - >-
    Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 <
    ad97b9a55246eb940a26ac977f80892a395cabf9
  - >-
    Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 <
    5edb9854f8df5428b40990a1c7d60507da5bd330
  - >-
    Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 <
    526394af4e8ade89cacd1a9ce2b97712712fcc34
  - >-
    Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 <
    b75070823b89009f5123fd0e05a8e0c3d39937c1
  - >-
    Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 <
    1b68efce6dd483d22f50d0d3800c4cfda14b1305
  - >-
    Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 <
    b7880cb166ab62c2409046b2347261abf701530e
  - Linux ef792d6ce0db6a56e56743b1de1716a982c3b851
  - Linux >= 5.9.9 < 5.10
  - Linux 5.10
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-06-10T20:41:33.152666Z'
published: '2026-02-04'
updated: '2026-10-19'
sourceUpdated: '2026-10-19T18:25:30.652Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-23097'
references:
  - url: 'https://git.kernel.org/stable/c/e7396d23f9d5739f56cf9ab430c3a169f5508394'
  - url: 'https://git.kernel.org/stable/c/ad97b9a55246eb940a26ac977f80892a395cabf9'
  - url: 'https://git.kernel.org/stable/c/5edb9854f8df5428b40990a1c7d60507da5bd330'
  - url: 'https://git.kernel.org/stable/c/526394af4e8ade89cacd1a9ce2b97712712fcc34'
  - url: 'https://git.kernel.org/stable/c/b75070823b89009f5123fd0e05a8e0c3d39937c1'
  - url: 'https://git.kernel.org/stable/c/1b68efce6dd483d22f50d0d3800c4cfda14b1305'
  - url: 'https://git.kernel.org/stable/c/b7880cb166ab62c2409046b2347261abf701530e'
tags:
  - cve.org
epss: 0.00134
epssPercentile: 0.02572
ingestedAt: '2026-10-19T18:35:50.104Z'
---

## Overview

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

- `Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 < e7396d23f9d5739f56cf9ab430c3a169f5508394`
- `Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 < ad97b9a55246eb940a26ac977f80892a395cabf9`
- `Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 < 5edb9854f8df5428b40990a1c7d60507da5bd330`
- `Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 < 526394af4e8ade89cacd1a9ce2b97712712fcc34`
- `Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 < b75070823b89009f5123fd0e05a8e0c3d39937c1`
- `Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 < 1b68efce6dd483d22f50d0d3800c4cfda14b1305`
- `Linux >= 336bf30eb76580b579dc711ded5d599d905c0217 < b7880cb166ab62c2409046b2347261abf701530e`
- `Linux ef792d6ce0db6a56e56743b1de1716a982c3b851`
- `Linux >= 5.9.9 < 5.10`
- `Linux 5.10`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.