{"id":"CVE-2026-93216","revision":"ec06bd4f6cbe4adf854e749e784e8e21","records":[{"revision":"ec06bd4f6cbe4adf854e749e784e8e21","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-93216","aliases":[],"title":"mm/page_owner: use memcg_data snapshot to avoid TOCTOU in print_page_owner_memcg()","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.","state":0,"publishedAt":"2026-09-24T15:10:38.702+00:00","modifiedAt":"2026-10-21T12:52:21.777+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"mm/page_owner.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"fcf8935832b86d3437f00e732c6d0d4d2819d6a9\",\n                            \"lessThan\": \"e7c1923c5f30a6953f0540e3171d882ec17b05d3\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"fcf8935832b86d3437f00e732c6d0d4d2819d6a9\",\n                            \"lessThan\": \"a4c940ab3f794f221a338c9431ad1ce0d73a2bea\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"fcf8935832b86d3437f00e732c6d0d4d2819d6a9\",\n                            \"lessThan\": \"46761406e14381dc35f498c247a87565b87ea2ef\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"fcf8935832b86d3437f00e732c6d0d4d2819d6a9\",\n                            \"lessThan\": \"90f095b816e25c6a9e4446d299bac5007fdcb3df\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"mm/page_owner.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"5.18\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"5.18\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.160\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.114\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.4\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/e7c1923c5f30a6953f0540e3171d882ec17b05d3","https://git.kernel.org/stable/c/a4c940ab3f794f221a338c9431ad1ce0d73a2bea","https://git.kernel.org/stable/c/46761406e14381dc35f498c247a87565b87ea2ef","https://git.kernel.org/stable/c/90f095b816e25c6a9e4446d299bac5007fdcb3df"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-93216","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-93216","identifiers":["CVE-2026-93216"]},"retained":false,"historicalAffected":[]}],"coverage":[]}