{"id":"CVE-2026-93216","published":"2026-09-24T16:17:16.670","lastModified":"2026-09-24T16:17:16.670","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/page_owner: use memcg_data snapshot to avoid TOCTOU in print_page_owner_memcg()\n\nprint_page_owner_memcg() reads page->memcg_data via READ_ONCE() at the\nstart to guard against tail pages and NULL data.  However, it later\nre-reads page->memcg_data locklessly in two places:\n\n1: page_memcg_check(page)\n\n2: PageMemcgKmem(page) (via folio_memcg_kmem(), which includes\n   VM_BUG_ON assertions for tail pages and MEMCG_DATA_OBJEXTS)\n\nIf the page is concurrently freed and reallocated as a THP tail page or\nslab page between these calls, the VM_BUG_ON assertions can trigger on\nCONFIG_DEBUG_VM=y builds, crashing the kernel.\n\nFix both TOCTOU issues by using the memcg_data snapshot throughout.","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/46761406e14381dc35f498c247a87565b87ea2ef","tags":[]},{"url":"https://git.kernel.org/stable/c/90f095b816e25c6a9e4446d299bac5007fdcb3df","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}