In the Linux kernel, the following vulnerability has been resolved:

ARC: mm: fix leakage of memory allocated for PTE

Since commit d9820ff ("ARC: mm: switch pgtable_t back to struct page *")
a memory leakage problem occurs. Memory allocated for page table entries
not released during process termination. This issue can be reproduced by
a small program that allocates a large amount of memory. After several
runs, you'll see that the amount of free memory has reduced and will
continue to reduce after each run. All ARC CPUs are effected by this
issue. The issue was introduced since the kernel stable release v5.15-rc1.

As described in commit d9820ff after switch pgtable_t back to struct
page *, a pointer to "struct page" and appropriate functions are used to
allocate and free a memory page for PTEs, but the pmd_pgtable macro hasn't
changed and returns the direct virtual address from the PMD (PGD) entry.
Than this address used as a parameter in the __pte_free() and as a result
this function couldn't release memory page allocated for PTEs.

Fix this issue by changing the pmd_pgtable macro and returning pointer to
struct page.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 01 Oct 2025 12:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: ARC: mm: fix leakage of memory allocated for PTE Since commit d9820ff ("ARC: mm: switch pgtable_t back to struct page *") a memory leakage problem occurs. Memory allocated for page table entries not released during process termination. This issue can be reproduced by a small program that allocates a large amount of memory. After several runs, you'll see that the amount of free memory has reduced and will continue to reduce after each run. All ARC CPUs are effected by this issue. The issue was introduced since the kernel stable release v5.15-rc1. As described in commit d9820ff after switch pgtable_t back to struct page *, a pointer to "struct page" and appropriate functions are used to allocate and free a memory page for PTEs, but the pmd_pgtable macro hasn't changed and returns the direct virtual address from the PMD (PGD) entry. Than this address used as a parameter in the __pte_free() and as a result this function couldn't release memory page allocated for PTEs. Fix this issue by changing the pmd_pgtable macro and returning pointer to struct page.
Title ARC: mm: fix leakage of memory allocated for PTE
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-10-01T11:45:20.854Z

Reserved: 2025-09-17T14:53:07.011Z

Link: CVE-2022-50446

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2025-10-01T12:15:37.037

Modified: 2025-10-01T12:15:37.037

Link: CVE-2022-50446

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.