CVE-2026-72172

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux6fd3620b342861de9547ea01d28f664892ef51a1 < 511a60e71aec308b24722cffc1912bf6befb87bfaffected
LinuxLinux6fd3620b342861de9547ea01d28f664892ef51a1 < 11f2826e9ee6f24aaa774e3dcd75abbe4b3091b6affected
LinuxLinux6fd3620b342861de9547ea01d28f664892ef51a1 < da5234df0941665f3a3f5b80f3dab94046537be0affected
LinuxLinux6fd3620b342861de9547ea01d28f664892ef51a1 < b91e27bce37cab9f35de0059278ebe457ca9878baffected
LinuxLinux6fd3620b342861de9547ea01d28f664892ef51a1 < cd681403a87085562499d60325b7b45d3be11217affected
LinuxLinux5.19affected
LinuxLinux0 < 5.19unaffected
LinuxLinux6.6.145 <= 6.6.*unaffected
LinuxLinux6.12.97 <= 6.12.*unaffected
LinuxLinux6.18.40 <= 6.18.*unaffected
LinuxLinux7.1.5 <= 7.1.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References