Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: mm/page_table_check: skip special zero mappings page_table_check_set() and page_table_check_clear() account mappings based on PageAnon(). Shared zero-page PTEs and huge zero PMDs are special mappings, but page_table_check can still account them as file-backed pages. An unprivileged process can populate enough zero mappings to overflow file_map_count and hit the existing BUG_ON(). The PTE path can do this with the shared zero page, and the PMD path can do the same with huge zero mappings. Skip special zero mappings in the user page-table accounting paths. Keep the PTE-side pte_special() check, and identify huge zero PMDs from the mapped folio instead of pmd_special(). That covers architectures where pmd_special() is a no-op without adding huge_zero_pfn checks to the generic counter helpers.
References
- https://git.kernel.org/stable/c/8db4bab826ccc9ec10fa41736a48031cd338d392
- https://git.kernel.org/stable/c/b726eb3c94d23e09da0e0f46b0fa09fb2b5d99cc
FAQ
What is CVE-2026-74600?
CVE-2026-74600 is a documented vulnerability. In the Linux kernel, the following vulnerability has been resolved: mm/page_table_check: skip special zero mappings page_table_check_set() and page_table_check_clear() account mappings based on Page...
How severe is CVE-2026-74600?
CVSS scoring is not yet available for CVE-2026-74600. Check NVD for updates.
Is there a patch for CVE-2026-74600?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.