CVE-2022-49172 parisc: Fix non-access data TLB cache flush faults
A flaw in the Linux kernel's parisc architecture cache flushing can lead to memory corruption and potential code execution or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2022-49172?
CVE-2022-49172 is a high-severity memory corruption vulnerability in Linux kernel, published on 26 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official 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.
Which versions are affected by CVE-2022-49172?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-49172?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2022-49172 being exploited?
There is no known exploitation of CVE-2022-49172 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-49172, GHSA-fc9v-5389-h387, ROOT-OS-DEBIAN-11-CVE-2022-49172, ROOT-OS-UBUNTU-2204-CVE-2022-49172, UBUNTU-CVE-2022-49172.