In the Linux kernel, the following vulnerability has been resolved: x86/mm/ident_map: Use gbpages only where full GB page should be mapped. When ident_pud_init() uses only GB pages to create identity maps, large ranges of addresses not actually requested can be included in the resulting table; a 4K request will map a full GB. This can include a lot of extra address space past that requested, including areas marked reserved by the BIOS. That allows processor speculation into reserved regions, that on UV systems can cause system halts. Only use GB pages when map creation requests include the full GB page of space. Fall back to using smaller 2M pages when only portions of a GB page are included in the request. No attempt is made to coalesce mapping requests. If a request requires a map entry at the 2M (pmd) level, subsequent mapping requests within the same 1G region will also be at the pmd level, even if adjacent or overlapping such requests could have been combined to map a full GB page. Existing usage starts with larger regions and then adds smaller regions, so this should not have any great consequence.
History

Fri, 25 Oct 2024 20:45:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Weaknesses NVD-CWE-noinfo
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel

Wed, 23 Oct 2024 01:30:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate


Tue, 22 Oct 2024 14:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 21 Oct 2024 19:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: x86/mm/ident_map: Use gbpages only where full GB page should be mapped. When ident_pud_init() uses only GB pages to create identity maps, large ranges of addresses not actually requested can be included in the resulting table; a 4K request will map a full GB. This can include a lot of extra address space past that requested, including areas marked reserved by the BIOS. That allows processor speculation into reserved regions, that on UV systems can cause system halts. Only use GB pages when map creation requests include the full GB page of space. Fall back to using smaller 2M pages when only portions of a GB page are included in the request. No attempt is made to coalesce mapping requests. If a request requires a map entry at the 2M (pmd) level, subsequent mapping requests within the same 1G region will also be at the pmd level, even if adjacent or overlapping such requests could have been combined to map a full GB page. Existing usage starts with larger regions and then adds smaller regions, so this should not have any great consequence.
Title x86/mm/ident_map: Use gbpages only where full GB page should be mapped.
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2024-10-21T18:54:07.811Z

Updated: 2024-11-05T09:53:33.677Z

Reserved: 2024-10-21T12:17:06.063Z

Link: CVE-2024-50017

cve-icon Vulnrichment

Updated: 2024-10-22T13:27:56.614Z

cve-icon NVD

Status : Analyzed

Published: 2024-10-21T19:15:05.043

Modified: 2024-10-25T20:15:50.067

Link: CVE-2024-50017

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-10-21T00:00:00Z

Links: CVE-2024-50017 - Bugzilla