{"apiVersion":"1.0","identifier":"CVE-2026-80719","description":"In the Linux kernel, the following vulnerability has been resolved: mm: mglru: fix stale batch updates after memcg reparenting The mglru page table walker batches per-generation size deltas in walk->nr_pages while walking page tables without holding the lruvec lock. The reset_batch_size() later folds those deltas into walk->lruvec under the lruvec lock. The page table walker can run concurrently with the memcg reparenting path as follows: CPU0 CPU1 ==== ==== walk_mm --> walk_page_range --> update_batch_size --> walk->nr_pages += delta mem_cgroup_css_offline --> memcg_reparent_objcgs --> lock lruvec lru_gen_reparent_memcg --> reparent child folios to parent unlock lruvec lock lruvec reset_batch_size --> child lrugen->nr_pages += delta This will trigger the following warning in lru_gen_exit_memcg(): VM_WARN_ON_ONCE(memchr_inv(lruvec->lrugen.nr_pages, 0, sizeof(lruvec->lrugen.nr_pages))); And the user-visible impact of underestimated nr_pages in MGLRU was premature OOMs because MGLRU does not try to reclaim memory when nr_pages reaches zero, but there are still more pages. To fix it, make reset_batch_size() check CSS_DYING under RCU before flushing the pending batch. A non-dying memcg keeps the original lruvec stable against RCU-delayed offlining; a dying memcg redirects the deltas to the first non-dying ancestor.","publishedAt":"2026-08-28T08:16:57","lastModifiedAt":"2026-08-28T08:16:57","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-80719","cvssScore":null,"cvssVector":"Pending","epssProbability":0.00145,"riskScore":0,"affectedProduct":"Linux kernel","affectedVersions":"unknown","vulnerabilityType":"Kernel","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-80719","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-80719","en":"https://www.redsauce.net/en/cves/CVE-2026-80719","fr":"https://www.redsauce.net/fr/cves/CVE-2026-80719","pt":"https://www.redsauce.net/pt/cves/CVE-2026-80719","de":"https://www.redsauce.net/de/cves/CVE-2026-80719","sk":"https://www.redsauce.net/sk/cves/CVE-2026-80719","el":"https://www.redsauce.net/el/cves/CVE-2026-80719"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-80719"}}