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

fs/proc/task_mmu: fix loss of young/dirty bits during pagemap scan

make_uffd_wp_pte() was previously doing:

pte = ptep_get(ptep);
ptep_modify_prot_start(ptep);
pte = pte_mkuffd_wp(pte);
ptep_modify_prot_commit(ptep, pte);

But if another thread accessed or dirtied the pte between the first 2
calls, this could lead to loss of that information. Since
ptep_modify_prot_start() gets and clears atomically, the following is the
correct pattern and prevents any possible race. Any access after the
first call would see an invalid pte and cause a fault:

pte = ptep_modify_prot_start(ptep);
pte = pte_mkuffd_wp(pte);
ptep_modify_prot_commit(ptep, pte);
History

No history.

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-05-04T09:12:32.403Z

Reserved: 2024-05-30T15:25:07.073Z

Link: CVE-2024-36943

cve-icon Vulnrichment

Updated: 2024-08-02T03:43:50.375Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2024-05-30T16:15:17.307

Modified: 2024-11-21T09:22:52.417

Link: CVE-2024-36943

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-05-30T00:00:00Z

Links: CVE-2024-36943 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2025-07-12T22:31:27Z