CVE-2026-72175

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

fs/proc/task_mmu: fix make_uffd_wp_huge_pte() prot-update race

Patch series "userfaultfd/pagemap: pre-existing fixes".

These are pre-existing bug fixes that were carried at the front of the

userfaultfd RWP working-set-tracking series up to v5 [1]. Per review

feedback that fixes should not sit in the middle of a feature series, they

are split out and sent on their own; the RWP series is reposted rebased on

top of this.

All six were flagged by the Sashiko AI review of the RWP series and carry

independent of RWP, apply to mm-new directly, and carry Cc: stable@.

1: fs/proc/task_mmu: a missing huge_ptep_modify_prot_start() in

make_uffd_wp_huge_pte() can lose hardware Dirty/Accessed updates

when PAGEMAP_SCAN write-protects a hugetlb PTE.

2: fs/proc/task_mmu: pagemap_scan_hugetlb_entry() compares the range

against HPAGE_SIZE rather than the hstate page size, so it never

write-protects gigantic h

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References