CVE Catalog

CVE-2026-93216

Unknown
Published: Translated: NVD NIST

Summary

In the Linux kernel's mm/page_owner, print_page_owner_memcg() re-reads page->memcg_data locklessly in two places, creating a TOCTOU condition. If the page is concurrently freed and reallocated as a THP tail page or slab page, VM_BUG_ON assertions can crash the kernel.

Risk Assessment

This can cause a kernel crash on CONFIG_DEBUG_VM=y builds, posing a denial of service (DoS) risk.

Recommendation

Update the Linux kernel to a version containing the fix that uses the memcg_data snapshot throughout.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: mm/page_owner: use memcg_data snapshot to avoid TOCTOU in print_page_owner_memcg() print_page_owner_memcg() reads page->memcg_data via READ_ONCE() at the start to guard against tail pages and NULL data. However, it later re-reads page->memcg_data locklessly in two places: 1: page_memcg_check(page) 2: PageMemcgKmem(page) (via folio_memcg_kmem(), which includes VM_BUG_ON assertions for tail pages and MEMCG_DATA_OBJEXTS) If the page is concurrently freed and reallocated as a THP tail page or slab page between these calls, the VM_BUG_ON assertions can trigger on CONFIG_DEBUG_VM=y builds, crashing the kernel. Fix both TOCTOU issues by using the memcg_data snapshot throughout.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS