Description
In the Linux kernel, the following vulnerability has been resolved: mm/mm_init: fix uninitialized struct pages for ZONE_DEVICE If DAX memory is hotplugged into an unoccupied subsection of an early section, section_activate() reuses the unoptimized boot memmap. However, compound_nr_pages() still assumes that vmemmap optimization is in effect and initializes only the reduced number of struct pages. As a result, the remaining tail struct pages are left uninitialized, which can later lead to unexpected behavior or crashes. Fix this by treating early sections as unoptimized when calculating how many struct pages to initialize.
References6
- git.kernel.org/stable/c/11f2826e9ee6f24aaa774e3dcd75abbe4b3091b6
- git.kernel.org/stable/c/511a60e71aec308b24722cffc1912bf6befb87bf
- git.kernel.org/stable/c/b91e27bce37cab9f35de0059278ebe457ca9878b
- git.kernel.org/stable/c/c5ef574d57e4a701485c13f26822328c91f05413
- git.kernel.org/stable/c/cd681403a87085562499d60325b7b45d3be11217
- git.kernel.org/stable/c/da5234df0941665f3a3f5b80f3dab94046537be0
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 6 · as of 11 November 2026
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