In the Linux kernel, the following vulnerability has been resolved: parisc: Fix non-access data TLB cache flush faults When a page is not present, we get non-access data TLB faults from the fdc and fic instructions in flush_user_dcache_range_asm and flush_user_icache_range_asm. When these occur, the cache line is not invalidated and potentially we get memory corruption. The problem was hidden by the nullification of the flush instructions. These faults also affect performance. With pa8800/pa8900 processors, there will be 32 faults per 4 KB page since the cache line is 128 bytes. There will be more faults with earlier processors. The problem is fixed by using flush_cache_pages(). It does the flush using a tmp alias mapping. The flush_cache_pages() call in flush_cache_range() flushed too large a range. V2: Remove unnecessary preempt_disable() and preempt_enable() calls.
History

Thu, 27 Feb 2025 01:45:00 +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

Low


Wed, 26 Feb 2025 02:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: parisc: Fix non-access data TLB cache flush faults When a page is not present, we get non-access data TLB faults from the fdc and fic instructions in flush_user_dcache_range_asm and flush_user_icache_range_asm. When these occur, the cache line is not invalidated and potentially we get memory corruption. The problem was hidden by the nullification of the flush instructions. These faults also affect performance. With pa8800/pa8900 processors, there will be 32 faults per 4 KB page since the cache line is 128 bytes. There will be more faults with earlier processors. The problem is fixed by using flush_cache_pages(). It does the flush using a tmp alias mapping. The flush_cache_pages() call in flush_cache_range() flushed too large a range. V2: Remove unnecessary preempt_disable() and preempt_enable() calls.
Title parisc: Fix non-access data TLB cache flush faults
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2025-02-26T01:55:28.628Z

Updated: 2025-05-04T08:31:33.041Z

Reserved: 2025-02-26T01:49:39.279Z

Link: CVE-2022-49172

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2025-02-26T07:00:54.313

Modified: 2025-02-26T07:00:54.313

Link: CVE-2022-49172

cve-icon Redhat

Severity : Low

Publid Date: 2025-02-26T00:00:00Z

Links: CVE-2022-49172 - Bugzilla