CVE-2025-38447

I

n the Linux kernel, the following vulnerability has been resolved: mm/rmap: fix potential out-of-bounds page table access during batched unmap As pointed out by David[1], the batched unmap logic in try_to_unmap_one() may read past the end of a PTE table when a large folio's PTE mappings are not fully contained within a single page table. While this scenario might be rare, an issue triggerable from userspace must be fixed regardless of its likelihood. This patch fixes the out-of-bounds access by refactoring the logic into a new helper, folio_unmap_pte_batch(). The new helper correctly calculates the safe batch size by capping the scan at both the VMA and PMD boundaries. To simplify the code, it also supports partial batching (i.e., any number of pages from 1 up to the calculated safe maximum), as there is no strong reason to special-case for fully mapped folios.

Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.16:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.16:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.16:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.16:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.16:rc5:*:*:*:*:*:*

History

19 Nov 2025, 17:49

Type Values Removed Values Added
CPE cpe:2.3:o:linux:linux_kernel:6.16:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.16:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.16:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.16:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.16:rc3:*:*:*:*:*:*
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 7.1
CWE CWE-125
References () https://git.kernel.org/stable/c/510fe9c15d07e765d96be9a9dc37e5057c6c09f4 - () https://git.kernel.org/stable/c/510fe9c15d07e765d96be9a9dc37e5057c6c09f4 - Patch
References () https://git.kernel.org/stable/c/ddd05742b45b083975a0855ef6ebbf88cf1f532a - () https://git.kernel.org/stable/c/ddd05742b45b083975a0855ef6ebbf88cf1f532a - Patch
First Time Linux linux Kernel
Linux

29 Jul 2025, 14:14

Type Values Removed Values Added
New CVE

Information

Published : 2025-07-25 16:15

Updated : 2025-11-19 17:49


NVD link : CVE-2025-38447

Mitre link : CVE-2025-38447

CVE.ORG link : CVE-2025-38447


JSON object : View

Products Affected
CWE
CWE-125

Out-of-bounds Read