CVE-2026-80718mm/percpu-km: fix bitmap overflow and accounting in pcpu_create_chunk()
Updated under an hour ago ()
Does this affect you?
It affects Linux. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
In the Linux kernel, the following vulnerability has been resolved: mm/percpu-km: fix bitmap overflow and accounting in pcpu_create_chunk() In pcpu_create_chunk(), nr_pages is the total contiguous backing allocation, i.e., nr_units * pcpu_unit_pages, but pcpu_chunk_populated() uses it to set chunk->populated, whose size is pcpu_unit_pages, bitmap. Since bit N in chunk->populated means page offset N inside every unit is backed. When nr_units > 1, the function writes beyond chunk->populated. Fix it by using chunk->nr_pages. It also fixes the global pcpu_nr_empty_pop_pages accounting, since pcpu_balance_free() only iterates up to chunk->nr_pages. Commit a63d4ac4ab609 ("percpu: make percpu-km set chunk->populated bitmap properly") introduced the bitmap overflow issue. Later, commit b539b87fed37f ("percpu: implmeent pcpu_nr_empty_pop_pages and chunk->nr_populated") added pcpu_nr_empty_pop_pages and caused the accounting issue.
- CVSS
- 7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Weakness (CWE)
- Not given
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Linux
- NVD analysis
- Received
- Record last updated
- Aug 29, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Linux Linux linux:linux (from the name) | from a63d4ac4ab6094c051a5a240260d16117a7a2f86 before 5f43d2c1bea280dcdfabaf156c25e7402fb8039f; from a63d4ac4ab6094c051a5a240260d16117a7a2f86 before 92c43ac3c2b09eb16162e8144e73c00b7c3e29d6; from a63d4ac4ab6094c051a5a240260d16117a7a2f86 before 6fc7da2a052f2825fff785e860e67183f5acaaba; from a63d4ac4ab6094c051a5a240260d16117a7a2f86 before 01504da375f5b19df195cb1cb1cf1dd184318f97; from a63d4ac4ab6094c051a5a240260d16117a7a2f86 before a6940b84c8c035da465b7165fdfcfb005545724e; from a63d4ac4ab6094c051a5a240260d16117a7a2f86 before 32134cf9211b83bed9076d0739c5906fbea4c763; from a63d4ac4ab6094c051a5a240260d16117a7a2f86 before 5c7fc39bf19abb38a996aaad77b3e3a8f48581c3; from a63d4ac4ab6094c051a5a240260d16117a7a2f86 before 89b1b79c308818a715e75f28744b70d8940a07c9 | CNA record |
References
- https://git.kernel.org/stable/c/5f43d2c1bea280dcdfabaf156c25e7402fb8039f
- https://git.kernel.org/stable/c/92c43ac3c2b09eb16162e8144e73c00b7c3e29d6
- https://git.kernel.org/stable/c/6fc7da2a052f2825fff785e860e67183f5acaaba
- https://git.kernel.org/stable/c/01504da375f5b19df195cb1cb1cf1dd184318f97
- https://git.kernel.org/stable/c/a6940b84c8c035da465b7165fdfcfb005545724e
- https://git.kernel.org/stable/c/32134cf9211b83bed9076d0739c5906fbea4c763
- https://git.kernel.org/stable/c/5c7fc39bf19abb38a996aaad77b3e3a8f48581c3
- https://git.kernel.org/stable/c/89b1b79c308818a715e75f28744b70d8940a07c9
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.