Description (CNA)
In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: fix hugetlb cgroup rsvd charge/uncharge mismatch In alloc_hugetlb_folio(), a single h_cg pointer is used for both the rsvd and non-rsvd hugetlb cgroup charges. When map_chg is set, hugetlb_cgroup_charge_cgroup_rsvd() stores the charged cgroup in h_cg, but the immediately following hugetlb_cgroup_charge_cgroup() overwrites h_cg with the non-rsvd cgroup pointer. As a result, hugetlb_cgroup_commit_charge_rsvd() stores the wrong (non-rsvd) cgroup pointer into the folio's rsvd slot. When the folio is later freed, free_huge_folio() unconditionally calls both hugetlb_cgroup_uncharge_folio() and hugetlb_cgroup_uncharge_folio_rsvd(). The rsvd uncharge reads back the wrong cgroup from the folio and decrements a counter that was never charged for that cgroup, causing a page_counter underflow: page_counter underflow: -512 nr_pages=512 WARNING: mm/page_counter.c:61 at page_counter_cancel Fix this by introducing a separate h_cg_rsvd pointer exclusively for the rsvd charge path, keeping the rsvd and non-rsvd charges fully independent through their charge, commit, and error uncharge paths.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected 08cf9faf7558020aed6a0da5810b824b07139dfa before 043c509f2488033c68c46d2de2af082fcd568612; affected 08cf9faf7558020aed6a0da5810b824b07139dfa before 5c32ae4a91fb5f4941328e0c1720a7fa4189c3bd; affected 08cf9faf7558020aed6a0da5810b824b07139dfa before 1697d253f51cf5e3825a3423ff49e128a3502ab2; affected 08cf9faf7558020aed6a0da5810b824b07139dfa before b785f2bd9496facedc0a031be09cddcd1d3c84d3; affected 08cf9faf7558020aed6a0da5810b824b07139dfa before 15807d0ddde37407af72859426b654f3d1972b00 |
| Linux / Linux | affected 5.7; unaffected 0 before 5.7; unaffected 6.6.160 through 6.6.*; unaffected 6.12.101 through 6.12.*; unaffected 6.18.40 through 6.18.*; unaffected 7.1.5 through 7.1.*; unaffected 7.2 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/043c509f2488033c68c46d2de2af082fcd568612
- https://git.kernel.org/stable/c/5c32ae4a91fb5f4941328e0c1720a7fa4189c3bd
- https://git.kernel.org/stable/c/1697d253f51cf5e3825a3423ff49e128a3502ab2
- https://git.kernel.org/stable/c/b785f2bd9496facedc0a031be09cddcd1d3c84d3
- https://git.kernel.org/stable/c/15807d0ddde37407af72859426b654f3d1972b00
ADP enrichment
No English description supplied.
No references supplied.