CVE-2025-68179

Description

In the Linux kernel, the following vulnerability has been resolved:s390: Disable ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAPAs reported by Luiz Capitulino enabling HVO on s390 leads to reproduciblecrashes. The problem is that kernel page tables are modified withoutflushing corresponding TLB entries.Even if it looks like the empty flush_tlb_all() implementation on s390 isthe problem, it is actually a different problem: on s390 it is not allowedto replace an active/valid page table entry with another valid page tableentry without the detour over an invalid entry. A direct replacement maylead to random crashes and/or data corruption.In order to invalidate an entry special instructions have to be used(e.g. ipte or idte). Alternatively there are also special instructionsavailable which allow to replace a valid entry with a different validentry (e.g. crdte or cspg).Given that the HVO code currently does not provide the hooks to allow foran implementation which is compliant with the s390 architecturerequirements, disable ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP again, which isbasically a revert of the original patch which enabled it.

Risk Information

Associated Vulnerability

Patch Details

References

https://nvd.nist.gov/vuln/detail/CVE-2023-1234
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1234