CVE-2026-80685

Summary

In the Linux kernel, the following vulnerability has been resolved:

mm/util: don't read __page_2 for order-1 folios in snapshot_page()

snapshot_page() currently reads __page_2 after checking nr_pages > 1, but it should only do so when nr_pages > 2.

If an order-1 folio is allocated at the end of a vmemmap section, __page_2 will not exist and reading it will cause a fault.

During DLPAR memory remove on a 22 TB ppc64le LPAR, snapshot_page() oopsed on the page isolation path while reading an order-1 folio's __page_2 from an adjacent absent section (unmapped vmemmap).

Fix this to avoid reading memmap that doesn't exist (e.g., a vmemmap hole).

Affected Software

VendorProductVersion RangeStatus
LinuxLinux31a31da8a6187f1e5448ec73222e01d7d3fed4aa < 9668ffe0e2a5e2399dce281620198a2e415871fcaffected
LinuxLinux31a31da8a6187f1e5448ec73222e01d7d3fed4aa < c649324571206a30949765320b91ccdb4c1722dcaffected
LinuxLinux31a31da8a6187f1e5448ec73222e01d7d3fed4aa < 7441d6348c70738e9ed307510db171c7a9b3f4bfaffected
LinuxLinux6.15affected
LinuxLinux0 < 6.15unaffected
LinuxLinux6.18.44 <= 6.18.*unaffected
LinuxLinux7.1.8 <= 7.1.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References