{"id":"CVE-2026-46017","title":"mm: fix deferred split queue races during migration","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm: fix deferred split queue races during migration\n\nmigrate_folio_move() records the deferred split queue state from src and\nreplays it on dst.  Replaying it after rem…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < cbf75cf212ee6e499abc1757fb4b5ae6d70ed0aa","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3bac01168982ec3e3bf87efdc1807c7933590a85","Linux < 7.0.4","Linux (all versions)"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-06T16:05:11.945193Z"},"published":"2026-05-27","updated":"2026-11-06","sourceUpdated":"2026-11-06T16:13:32.093Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-46017","references":[{"url":"https://git.kernel.org/stable/c/cbf75cf212ee6e499abc1757fb4b5ae6d70ed0aa"},{"url":"https://git.kernel.org/stable/c/3bac01168982ec3e3bf87efdc1807c7933590a85"}],"tags":["cve.org"],"epss":0.00105,"epssPercentile":0.01055,"ingestedAt":"2026-11-06T16:57:43.350Z","slug":"CVE-2026-46017","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nmm: fix deferred split queue races during migration\n\nmigrate_folio_move() records the deferred split queue state from src and\nreplays it on dst.  Replaying it after remove_migration_ptes(src, dst, 0)\nmakes dst visible before it is requeued, so a concurrent rmap-removal path\ncan mark dst partially mapped and trip the WARN in deferred_split_folio().\n\nMove the requeue before remove_migration_ptes() so dst is back on the\ndeferred split queue before it becomes visible again.\n\nBecause migration still holds dst locked at that point, teach\ndeferred_split_scan() to requeue a folio when folio_trylock() fails. \nOtherwise a fully mapped underused folio can be dequeued by the shrinker\nand silently lost from split_queue.\n\n[ziy@nvidia.com: move the comment]\n\n## Affected\n\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < cbf75cf212ee6e499abc1757fb4b5ae6d70ed0aa`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3bac01168982ec3e3bf87efdc1807c7933590a85`\n- `Linux < 7.0.4`\n- `Linux (all versions)`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}