CVE-2026-93216 (GCVE-0-2026-93216)

Vulnerability from cvelistv5 – Published: 2026-09-24 15:10 – Updated: 2026-10-21 12:52
VLAI
Title
mm/page_owner: use memcg_data snapshot to avoid TOCTOU in print_page_owner_memcg()
Summary
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.
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6638 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: fcf8935832b86d3437f00e732c6d0d4d2819d6a9 , < e7c1923c5f30a6953f0540e3171d882ec17b05d3 (git)
Affected: fcf8935832b86d3437f00e732c6d0d4d2819d6a9 , < a4c940ab3f794f221a338c9431ad1ce0d73a2bea (git)
Affected: fcf8935832b86d3437f00e732c6d0d4d2819d6a9 , < 46761406e14381dc35f498c247a87565b87ea2ef (git)
Affected: fcf8935832b86d3437f00e732c6d0d4d2819d6a9 , < 90f095b816e25c6a9e4446d299bac5007fdcb3df (git)
guessed Create a notification for this product.
Linux Linux Affected: 5.18
Unaffected: 0 , < 5.18 (semver)
Unaffected: 6.6.160 , ≤ 6.6.* (semver)
Unaffected: 6.12.114 , ≤ 6.12.* (semver)
Unaffected: 7.2.4 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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{
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          "programFiles": [
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    "dateReserved": "2026-09-17T16:02:15.093Z",
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}



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