CVE-2026-23097 migrate: correct lock ordering for hugetlb file folios

Medium 5.5 Published Updated

A lock ordering error in the Linux kernel's hugetlb migration path can cause a deadlock, leading to a denial of service.

Exploited in the wild
Not known
Login needed
Any signed-in user
Attackable
Local or same network only
Victim action needed
Not needed
Fix
Available

What is CVE-2026-23097?

CVE-2026-23097 is a medium-severity vulnerability in Linux kernel, published on 4 Feb 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official 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.

Weakness: CWE-362

Which versions are affected by CVE-2026-23097?

It affects 1 product.

Linux distribution packages (40)
bpftool AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-abi-stablelists AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-core AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-cross-headers AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-debug AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-debug-core AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-debug-devel AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-debug-modules AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-debug-modules-extra AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-devel AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-doc AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-headers AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-modules AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-modules-extra AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-rt AlmaLinux:8All versions4.18.0-553.109.1.rt7.450.el8_10
kernel-rt-core AlmaLinux:8All versions4.18.0-553.109.1.rt7.450.el8_10
kernel-rt-debug AlmaLinux:8All versions4.18.0-553.109.1.rt7.450.el8_10
kernel-rt-debug-core AlmaLinux:8All versions4.18.0-553.109.1.rt7.450.el8_10
kernel-rt-debug-devel AlmaLinux:8All versions4.18.0-553.109.1.rt7.450.el8_10
kernel-rt-debug-modules AlmaLinux:8All versions4.18.0-553.109.1.rt7.450.el8_10
kernel-rt-debug-modules-extra AlmaLinux:8All versions4.18.0-553.109.1.rt7.450.el8_10
kernel-rt-devel AlmaLinux:8All versions4.18.0-553.109.1.rt7.450.el8_10
kernel-rt-modules AlmaLinux:8All versions4.18.0-553.109.1.rt7.450.el8_10
kernel-rt-modules-extra AlmaLinux:8All versions4.18.0-553.109.1.rt7.450.el8_10
kernel-tools AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-tools-libs AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-tools-libs-devel AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-zfcpdump AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-zfcpdump-core AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-zfcpdump-devel AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-zfcpdump-modules AlmaLinux:8All versions4.18.0-553.109.1.el8_10
kernel-zfcpdump-modules-extra AlmaLinux:8All versions4.18.0-553.109.1.el8_10
perf AlmaLinux:8All versions4.18.0-553.109.1.el8_10
python3-perf AlmaLinux:8All versions4.18.0-553.109.1.el8_10
bpftool Red Hat:enterprise_linux:8::baseosAll versions0:4.18.0-553.109.1.el8_10
bpftool-debuginfo Red Hat:enterprise_linux:8::baseosAll versions0:4.18.0-553.109.1.el8_10
kernel Red Hat:enterprise_linux:8::baseosAll versions0:4.18.0-553.109.1.el8_10
kernel-abi-stablelists Red Hat:enterprise_linux:8::baseosAll versions0:4.18.0-553.109.1.el8_10
kernel-core Red Hat:enterprise_linux:8::baseosAll versions0:4.18.0-553.109.1.el8_10

Products include Linux kernel.

How do I fix CVE-2026-23097?

Apply the vendor's patch.

Is CVE-2026-23097 being exploited?

There is no known exploitation of CVE-2026-23097 in the wild and no public exploit code.

All Linux kernel vulnerabilities

Sources

Also known as ALSA-2026:3463, ALSA-2026:3464, AZL-77181, BELL-CVE-2026-23097, DEBIAN-CVE-2026-23097, GHSA-3gqm-m375-7mp2 and 10 more.

Is CVE-2026-23097 in your software?

Upload an SBOM and sbomify checks it against every vulnerability here, every day.

Check your SBOMs for free